Liquidation Assessment through Strategic Financial Statement Analysis Essay

Liquidation Assessment through Strategic Financial Statement Analysis - Essay Example The present research has identified that the year 2009 witnessed liquidation of 19,077 companies as per the figures of the insolvency service representing an increase of 23% from the year 2008. and out of 19,077, 6,335 companies have been declared insolvent. According to Adam, the figures are 13,434 as voluntary liquidations and 5,643 are compulsory liquidations totaling 19,077 as per the above report. Again in the UK, Red Flag Alert says that more than 140,000 were showing signs of financial distress in q4 2009. The figure is 6 % higher than Q3 2009 but 14 % lesser than the identical period in 2008. The corporate failures seem to unstoppable despite fiscal support by the Government, VAT reductions by 2.5% and the HRMC’s payment support for  £ 4.2 bn covering 242,000 ‘time-to-pay arrangements’. The U.S.based Circuit City, second largest retailer of electronics next to Best Buy went into liquidation of its last retained store after series of one liquidation after another in early 2009 rendering their final tally of 30,000 of employees jobless. One commentator has said that it was a well deserved as a poorly managed company. Needless to say, a recession has been responsible for this state of affairs. Recessions are considered a process of the plumbing of economics that removes the inefficient entities and paves way for reallocation of capital and labor to the most deserving entities. The faster the reallocation, the safer the investments. The three ways in which insolvency is dealt with are the liquidation, rescue, and workout. Liquidation is the process administered by the court for sale of the assets of the insolvent firm in piecemeal. A rescue is again a court intervention for rehabilitation, reorganization or restructuring of the insolvent firm with the objective of preventing its liquidation. A workout is an informal process where a court has no role and the creditors either reschedule their debts or allow settlement of debts at a disco unt.

Improving Organisational Performance Essay Example | Topics and Well Written Essays - 3000 words - 1

Improving Organisational Performance - Essay Example Performance management is considered to be one of the most regarded Human Resource (HR) functions in an organisation. In most of the organisations, the performances of the subordinates are measured either formally or informally. Effective communication regarding performance appraisal generally takes place once in a year or once in a quarter. Nevertheless, performance management is a continuous phenomenon (Armstrong, 2006). When the performance management is utilised in a proper way then the management gains numerous benefits. It has been noted that most of the United Kingdom based organisations operate periodic performance appraisal systems. However, it has been noted that most of the employees as well as managers are found to be discontent with the schemes utilised in the organisations (Keshav & Sharma, n.d.). Appraisals are incapable of motivating the employees in an organisation and it has been claimed by the respondents to an Industrial Society Survey that such appraisals do not have any positive impact upon the workforce. Therefore, it becomes significant for the organisations to monitor the way in which performance management is being practiced (Management Today, 1998). The main objective of the paper is to evaluate business cases for the use of performance management at Barclays Bank and Lloyds Bank. ... will also present the practical difficulties, challenges as well as implications identified by the use of the performance management in Barclays Bank and Lloyds Bank. The methods that the two banks can use in order to mitigate the difficulties related to the performance management will also be recognised in a detailed way in this paper. Finally, the study will attempt to find out the potential limitations or shortcomings related to the proposals provided to the banks. Business Case for Performance Management at Barclays Bank People tend to differ in terms of their abilities as well as aptitudes. There will be major disparities between the size and the value of the same work upon the same job done by two distinct people. Therefore, under such note, it can be assumed that the organisations need performance management so that they are capable of comprehending the abilities of the employees, proficiencies as well as their comparative worth for the organisation. Offering rating to the emp loyees in terms of their performance can be done with the assistance of performance appraisal. Barclays Bank tends to extend its assistance in terms of financial services in approximately 50 countries all over the globe (Barclays, 2012). Barclays Bank is considered to be one of the famous companies in the banking sector and thus it states that the way in which the employees tend to perform their operations has a direct influence upon the business performance. The team members working for the bank are well aware of the goals that they are supposed to attain. In order to manage the performance, the bank has designed numerous actions in which the employees participate. Coaching is recognised to be one of the actions where a crucial objective is to make the employees aware of their job

International Standards for Financial Reporting Case Study

International Standards for Financial Reporting - Case Study Example Looking first to Profit Ratios, the investment analyst would take interest in the return on invested capital that is a measure of profits earned on the capital that is invested in the company. The profit ratios would inform an investor about the reliability of the company in the use of its resources. The more reliable and efficient a company the more profitable it will be. ROIC is of value as a benchmark for Morrisons or other investors to compare the company to compete in the marketplace, as well as to compare subsidiary companies that Morrisons envelopes (Hill and Jones C3). Over time, profit ratios can show if a company’s performance is improving or declining. There are many types of profit ratios, for Morrisons, the Return on Investment Capital ratio (ROIC) will be analyzed: ROIC = Net profit/Invested capital   = â‚ ¤ 93.4 million (over 25 weeks)/ â‚ ¤ 3, 662.4 million Thus, profits were down, before tax being â‚ ¤ 61.5 million. Although the overall financial re sult was disappointing for Morrisons in 2006, achievements were made; so it was a period of dramatic changes. Benchmarking has had a strong focus at Morrisons over the past financial year, and a range of company labeled products has been adapted and extended to meet market demands. Also, the retraining of almost 90, 000 Safeway employees has led to progress in the contributions of experience, skills, competencies, and knowledge that are of deemed value to the Morrisons team (Morrisons’ Annual Report 5).  Ã¢â‚¬â„¢ Annual Report 5). It appears from the Annual Report published by Morrisons, that ROIC weaknesses are being buffered by a

Psychoanalytical Approach Essay Example for Free

Psychoanalytical Approach Essay ?1. Psychoanalytical Criticism ?2. Psychoanalytical criticism is a type ofcriticism that uses theories of psychology to analyze literature. It focuses on theauthor’s state of mind or the state of the mind of fictional characters. ?3. Sigmund FreudPsychoanalytical criticism originated in the workof Sigmund Freud. Freud’s theories areconcerned with the nature of the unconsciousmind. According to Freud, the human mindconsists of three parts: the id, the ego andsuperego. ? The id is source of our instinctual and physical desires. ? The superego is the part of the psyche that has internalized the norms and mores of society. ? The ego is keeps mediating between the demands of the id and the superego. It is rational, logical, and conscious. ?4. Repression? We often repress what the id encourages us to think and do because the ego and superego tell us not to think and do, therefore forcing these unacceptable wishes into the unconscious. All of us have repressed wishes and fears.? Repressed desires emerge in disguised forms: dreams and language (slips). They emerge in symbolic form that require  analysis to reveal their meaning.? Many elements of psychology that Freud described appear in literary works. ?5. Freudian Literary Criticism? Freudian critics try to understand how the operations of repression structure or inform the work They pay close attention to unconscious motives and feelings, whether these be those of the author, or of the characters depicted in the work.? They demonstrate the presence in the literary work of classic psychoanalytic symptoms or conditions. ?6. Carl Gustav Jung and Jungian literary Criticism? Jung developed the theory of the collective unconscious, a collection of shared unconscious memories dating back to the origins of human experience and manifested in dreams, myths, and literature.? A great work of literature is not a disguised expression of repressed wishes, but a manifestation of the desires one held by the whole human race, and now repressed because of the advent of civilization.? Jungian analysis of literature tries to discover the images in a work of literature that a permanent and universal significance. ?7. Harold Bloom and the anxiety of InfluenceThe most important contemporary psychological criticis Harold Bloom. Bloom uses the Freudian concept ofrepression to apply it to literary history in general. Nopoet creates in isolation from his predecessors. In TheAnxiety of Influence, he argues that poetsunconsciously misread the poems of their greatpredecessors. The new poems are essentiallyrewritings of poems by a father-figure predecessor. Poets keep struggling to free themselves from thisinfluence of father-figure poets.

Effect of Structural Pounding During Seismic Events

Effect of Structural Pounding During Seismic Events Abstract This project entitled aims at the investigation of the effect of structural pounding to the dynamic response of structures subject to strong ground motions. In many cases structural pounding during earthquake may result in considerable and incalculable damages. It usually need to be accounted for in the case of adjacent structures, bridges, base isolated buildings, industrial and port facilities, and in ground pipelines. The phenomenon of that impact force pounding has been noted by researchers and engineers over the past several decades. As we see through dull historical strokes and performance, in different investigations of past and recent earthquakes damage have illustrated several cases of pounding damage such as those that have occurred in the Imperial Valley (May 18, 1940), the Sequenay earthquake in Canada (1988), Kasai Maison (1991), the Cairo earthquake (1992), the Northridge earthquake (1994), California (1994), Kobe, Japan (1995) Turkey (1999), Taiwan (1999) and Bhuj, Ce ntral Western India (2001). Some of the most memorable seismic events were in the 1972 Managua earthquake, when the five-storey Grant Hotel suffered a complete collapse, also in the 1964 Alaska earthquake, the 14-storey Anchorage Westwood hotel pounded against its low rise ballroom and the most recently extent of pounding in Mexico City in 1985 confirmed this as a major problem. Those all evidences have continued to illustrate the annihilation of earthquakes, with devastation of engineered in both buildings and bridges structures. Amongst the feasible structural destructions, seismic produced pounding has been frequently distinguished in numerous earthquakes, as a result this phenomenon plays a key role to the structures. As engineers, we have a responsibility to prevent it or take the necessary steps to mitigate it for the future constructions by considering the properties that affect and led pounding to occur. In order to examine the effect of the various parameters associated wit h pounding forces on the dynamic response of a seismically excited structure, a number of simulations and parametric studies have been performed, using SAP2000. By more precise investigations that have been done from professional earthquake investigators and engineers pounding produces acceleration and shear at various story levels. Also, significantly depends on the gap size between superstructure segments, which we will examine later on in the project. The main aim of the project is to conduct a detailed investigation on pounding-involved response structure during a seismic event as well as observed the structural behaviour as the result of ground motion excitation by examine the properties that affect pounding and determine the solutions and the mitigations that we have to take into account before we construct a structure in order to avoid future disasters. INTRODUCTION 1.1 Seismic Pounding effect (Overview) Looking throughout the time, investigations and observations of the effects of historical earthquakes have demonstrated that many structures are susceptible to significant damage which may lead to collapse. Numerous devastating earthquakes have hit various seismically active regions. Some investigations that have been followed after those seismic events are distinguished fact providing that, an earthquake within the range of six is capable of creating and generating incalculable and irreversible damages, of both buildings and bridges. Those seismic losses have further consequences, most likely to present economical problem to the community hit. The main target of most seismic excitations are, the primary frequencies of rigid buildings between the ranges of low to medium height, resulting by this in significant accumulations of soil acceleration. Also, addition to this is the causing the presence of the inevitable enduring seismic loads in engineered structures, creating inflexible re sponses. In recent years it becomes more urgent need to minimize seismic damage not only to avoid structures failures but especially in crucial building facilities such as hospitals, telecommunications etc. as well as the protection of the critical equipment that is accommodated by those buildings. (a)barrier rail damage (Northridge earthquake 1994) (b)Connector collapse (Northridge earthquake 1994) In seismically active areas the phenomenon of pounding may need to be accounted for, in the case of closely spaced structures to avoid extensive damages and human losses. The phenomenon of that impact force-pounding has been noted by earthquake investigators over the past several decades when the presence of pounding occurred into an extent. Looking throughout the time, some historical performance of pounding has been denoted, different investigations of past and recent earthquakes damage have illustrated several cases of pounding damage such as those that have occurred in the Imperial Valley (May 18, 1940), California (1994) the Northridge earthquake, Kobe, Japan (1995) and etc. in both engineered structures, buildings and bridges. One of the most remarkable example of pounding-involved destruction resulted from interactions between the Olive View Hospital main building and one of its independently standing stairway towers during the San Fernando earthquake of 1971. The extent of po unding was recently observed in Mexico City in 1985, which then it follows the most recent one in Central Western India (2001). Considerable pounding was observed at sites over 90 km from the epicentre thus indicating the possible catastrophic damage that may occur during future earthquakes having closer epicentres. Is remarkable to denote that pounding of adjacent buildings could have defective damage such as adjacent structures with different dynamic characteristics which vibrate out of phase and there is inadequate separation gap or energy diffusion system to board the relative moderate motions of adjacent buildings. (a)Collapse of a department store building (Northridge earthquake 1994) (b)Collapse of the first story of a wooden residential building (Northridge earthquake 1994) Several researchers considered the topic of pounding between adjacent buildings (Anagnostopoulos 1988; Maison Kasai, 1990; Papadramakis et al, 1996) with proving or deriving mathematical expression in order to evaluate and calculate the pounding force, by using experimental procedures. But few people have actually addressed the topic of pounding between adjacent buildings (Tsai, 1997; Malhotra, 1997; Matsagar Jangid, 2003; Komodromos et al 2007) for which the behaviour and the requirements differ from the conventional structures. Likewise, those projects are limited especially to the study and investigation of pounding between adjacent buildings and based isolated buildings without investigating the case of conflict with neighbouring buildings and the resulting of great deformations of the superstructure. In the past engineers couldnt prevent the pounding due to some factors such as the past seismic codes did not give explicit guidance, because of this and due to particular economical factors and considerations, that are concerning the maximum land usage requirements, especially in the high density populated areas of cities pounding was unavoidable. Due to that, we are able to identify and investigate many buildings in global system which are already been built in contact or overmuch close to another that could easily cause them to suffer from pounding damage in future earthquake strikes. A large rupture is controvertible from both aspects. The overcrowded construction system in many cities complements a dominant apprehension for seismic pounding damage. For these major reasons, it has been comprehensively acquired that pounding is a disastrous phenomenon that should be anticipated or mitigated. Acceleration range will guidance in many cases to quake activities which are appreciably h igher than designed by the design codes that have been used up to now. The most affordable and easy active way for mitigating pounding effects and diminishing pounding damage, is to consider enough separation gap size between close adjacent structures, this causing difficulties to be accomplished, owing to the detailing engineered work that supposed to be done and the high cost of land in this present time. A flipside to the seismic separation gap precaution in the construction design is to reduce the effect or pounding force through devaluating lateral motion, some researchers involved in extent with lateral ground motions due to pounding such as (Kasaiet al. 1996, Abdullah et a.2001, Jankowski et al 2000, Ruangrassamee Kawashima 2003, Kawashima Shoji 2000). This procedure can be accomplished by joining adjacent structures at critical locations of the supports so that their motion could be in-phase with one another or by lessening the pounding buildings damping capacity by means of passive structural control of energy dissipation system. 1.2 Pounding force and impact element Various impact elements are usually used to illustrate the pounding between adjoining construction buildings or bridge structures. Pounding between two conflicting structures, is often simulates by using contact force-based impact models such as the linear spring, Kelvin-Voigt element and Hertz contact model element, and additionally the restitution momentum-based stereo mechanical method. (a) (b) (c) Figure 1.2.1 shows the pounding problem in: (a) bridge structures [1] S. Mithikimar and R. DesRoches 2006; (b) adjacent buildings with link elements [2] V. Annasaheb Matsagar and R. Shyam Jangid 2005; (c) adjacent building with gap size structures [1] S. Mithikimar and R. DesRoches 2006; Also another view of pounding effect beyond that in buildings is on the bridges. Many damages during strong earthquakes have occurred in bridge due to pounding between the girders when the gap is not sufficient. From many experimental studies that have been made showed that pounding damage of a bridge can have severe after-effects as it has been observed in many major earthquakes, such as the 1994 Northridge earthquake etc. As we can see from our daily routine bridges belong to one of the important lifeline systems, their proper function play major role in both our life and in the culture, especially after a devastating earthquake in order to survive and/or recovery. According to some studies [3] Chouw and Hao (2003) and [4] Hai SUI et al. (2004) showed that gap size in the bridges plays the major key role for a bridge to survive under a pounding impact force. The examined the gap size and the outcomes showed that a smaller gap size can expect larger pounding force; therefore the possibility of damage of bridge decks is higher. So on in general designs a small gap should be avoided, if is possible. Moreover according to their experiment the results showed that friction device can decrease pounding impact force that works in different earthquakes. a) Multiple-pier bridge model [4] H. SU, et al 2004; b) Two Single degree of freedom model [4] H. SU, et al 2004; An adequate gap size can contribute to the reduction of pounding effect, but nevertheless in real life the gap size for the designs is unavoidable and due to the limited space that we have to build the design the gap size end up to has smaller values. And thus we resort to other solutions in order to reduce the pounding effect, such as the friction device and bumpers (steel spring with viscous damper). Moreover friction device is much more practical and effective than bumpers. Bumpers can avoid the immediate damage but they cannot reduce the pounding force between the bridge girders, in the other hand friction device can be applied to any earthquake and also is less sensitive to various ground movements. Linear spring element The linear spring element is the easiest and simplest contact element that used to model impact. When the gap between the adjoining structures adjournments, the spring take effect and is presentational of the force established in the meanwhile of impact force. According to Maison Kasai [5] (1992) have used this model widely, to study further analyse pounding between adjacent buildings. Nonetheless, the linear spring cannot resolve the energy dissipation during impact. The linear spring element illustrated in Figure 1.2.3(a). The Kelvin-Voigt Element The Kelvin-Voigt element can be described by a linear spring in parallel with a damper, as depicted in Figure 1.2.3(b), this model has been used in some studies [6] Anagnostopoulos, 1988; [7] Anagnostopoulos and Spiliopoulos, 1992; [8] Jankowski 2005; The linear spring illustrates the force during impact and the damper accounts for the energy dissipation during impact and is mostly used. The damping coefficient (ck) can be related to the coefficient of restitution (e), by equating the energy dissipations during impact, following the form of equations below: Where, and Kk is the stiffness of the contact spring, and m1, m2 are the masses of the colliding bodies. Hertz contact law Additionally, a non linear spring based on Hertz contact law can be used to model impact, as depicted in Figure 1.2.3(c). Nonetheless, the Hertz contact law is a characteristic representing of the static contact between elastic bodies and fails to contain energy loss during impact. The impact force can be expressed in the form of the equation below: Where R is the impact stiffness parameter that depends on the material properties of the colliding structures and the contact surface geometry, g is the at-rest separation and n is the Hertz coefficient. The use of the Hertz contact law has an intuitive appeal in modelling pounding, since one would expect the contact area between the colliding structures to increase as the contact force increases, leading to a non-linear stiffness described by the Hertz coefficient n which typically is taken ad 1.5. Several analysts have adopted this approach, including [9] Davis 1992; [10] Pantelides and Ma 1998; [11] Chau and Wei 2001; and [3] Chau et al. 2003; More, for pounding simulation we can also meet the Hertzdamp model, which is a contact model based on the Hertz contact law and using a non linear hysteresis damper. According to experimental theories, for low peak ground acceleration levels, Hertz model produces sufficing results and the Hertzdamp model can be used in advance for moderate and high peak ground acceleration levels (PGA). The contact element approach has its limitations, with the exact value of spring stiffness to be used, being unclear. Uncertainty in the impact stiffness arises from the unknown geometry of the impact surfaces, uncertain material properties under loading and variable impact velocities. The contact spring stiffness is typically taken as the in plane axial stiffness of the colliding structure (Maison and Kasai, 1990). Another reasonable estimate is twenty times the stiffness of the stiffer structure [6] Anagnostopoulos, 1988; However, using a very stiff spring can lead to numerical convergence difficulties and unrealistically high impact forces. The solution difficulties arise from the large changes in stiffness upon impact or contact loss, thus resulting in large unbalanced forces affecting the stability of the assembled equations of motion. (a) Linear spring element (b) Kelvin Voigt Element (c) Hertz non-linear spring element Figure 1.2.3: Various impact models and their contact force relations [12] Thomas G.Mezger 2006; 1.3 Method of Seismic Analysis 1.3.1 Non-linear Dynamic Analysis Non-linear Dynamic analysis involves step-by step in time integration of the non-linear governing equations of motion, a powerful analysis that can evaluate any given seismic event motion. An earthquake accelerogram is correlated and the consistent response-history of a structural model during seismic events is evaluated. Computer softwares have been designed for these kinds of purposes. Sap can utilized a non-linear dynamic analysis for both linear elastic and non-linear inelastic material response, using step by step integration methods. Is a suitable computer program that is able to evaluate and analyze the response of a two-dimensional and a three-dimensional non-linear structure taking as an input the accelerogram component of an Earthquake? This program will be used to analyse our structural model and to produce a real time of time-history displacement. In a nonlinear dynamic procedure the building model followed static procedures incorporating directly the inelastic material r esponse using in general finite elements. Because this program is using step-by step integration method of analysis the response of the structure, is one of the most sophisticated analysis procedure for predicting forces and displacements under seismic input. However, the calculated response can be very sensitive to the characteristics of the individual ground motion used as seismic input; therefore several time-history analyses are required using different ground motion records. The main value of nonlinear dynamic procedures has the objective to simulate the behaviour of a building structure in detail. 1.4 Main Objectives of this project The main focus of this project is the development of an analytical model that pounding force will present based on the classical impact theory by using parametric study to identify the most important parameters that affecting pounding. Those factors that give arise to that impact force, therefore investigate of the different practical types of structures that pounding can be occurred. The main objective and scope of this study are, to explore the global response of buildings structures when the pounding effects take place under seismic events, therefore to review the main outcomes of the literature and how the impact theory come across to the practical cases. Create a structural modelling and perform a non linear time history analysis on it. Examine the realistic model of pounding that we will create if it satisfies the properties in order for the structure to work. Determine the relative importance of the dynamic characteristics of pounding. Dynamic analysis will be carried out on the model structure to observe the displacement of the structure due to earthquake excitation. When we examine the main structure we are mainly concerned with displacement, velocity and acceleration, the general dynamic behaviour of the structure under the action of dynamic loads such as earthquake lateral loads. For the purpose of the project appropriate computer software will be used for its purposes (e.g. SAP2000). Creation and versatile of the model, accomplishment of the analysis, and checking and breakthrough of the design must be all done through this interface. Graphical displays of the results, including the real-time of time-history displacements will be easily produced by the use of that software. At the end of that modelling analysis by gathering all the necessary and useful outcomes and explored in deep the main parameters derived by this, the conclusion and results of what we have to adopt as engineering before retrofitting a structure. The appropriate structural parameters are the separation gap size between adjacent structures (storey mass, structural stiffness and yield strength etc.), the dynamic behaviour of a damped multi-degree of freedom bridge system separated by an expansion joint, considering the limited width of clearance around a seismically isolated buildings, that pounding can cause high over stresses when the colliding buildings have different height, periods or masses and the isolators in bridge structures are effective in mitigating the induced seismic forces, cable restrainers etc. Engineers should adopt those realistic facts before they construct new structures in order to succeed future sustainability of the structures and avoiding by this the impact phenomenon of pounding. Accomplish to mitigate the phenomenon of pounding in order to prevent future collisions and/or engineering disasters when seismic events occur. REVIEW OF LITERATURE 2.1 Practical Cases Pounding-impact force generated by earthquakes between different analytical structure models may provoke extensive damage and in general most of the times the result of that force is not pleasant, it may lead the structure to a total collision as it can be seen from different practical cases. Pounding problem is phenomenon that has been observed during earthquakes and in accordance to ground motions, and has been extensively investigated by various researchers that have used a variety of impact analytical models. Because of the importance of what pounding will have as a result of different engineering structures, attracted the attention of several scientists and analyzers? This absorption is a consequence fact of a plenty growing amount of evidence, which can be found in reports and journals, which have been created after dominant exceeding earthquakes. Demonstrating, the power of that certain impact force which may cause considerable damage. The conclusions and results of successive series of various numerical, integrated analytical and experimental studies have been conducted using individual structural models and administering different models of practical cases confirm that pounding, due to constraining additional impact forces, may result in damage as well as significantly increase the structural response. Moreover, there are many practical case histories of engineered buildings with different dynamic properties and characteristics, which have been constructed under the old earthquake resistant design codes. Analogous conditions concern also bridge constructions. When a structure is under earthquake vibrations will move according to ground motions. These vibrations can be entirely exaggerated, creating at the same time stresses and deformations throughout the structure. Evaluation of methods can be carry out in engineering practise to estimate the parameters that give a rise to pounding. The accuracy and the ability of computational appliance have increased a lot this century by helping us evaluate the seismic structural response of structure, a variety of softwares computing programs have been designed for those purposes, and can accomplished to calculate the dynamic seismic response of a structure which help engineers mitigate pounding effects in structure by avoiding future disaster s . Linear and nonlinear models are realistic pounding models that have been used for studying the performance of a structural system under the mode of structural pounding effect under seismic events. Significance to notice in seismically active areas the serious hazard that pounding can cause and in what practical cases does it occurs by review of some critical and enlightened journals and reports, according to history performance of an exceeding major earthquakes. Also a time history analysis is a dynamic tool for the investigation of a structural seismic enforcement. Because of all the above reasons, investigations have been carried out on pounding mitigation in order to improve the seismic response. 2.1.1 Linear and non-linear pounding of structural systems Pantellides and Ma [13] examined by experimental procedures, the dynamic response of a damped single degree-of-freedom structural model during a seismic event. They analysed the structural behaviour of SDF with both elastic and inelastic structural impact response by using realistic parameters for the pounding model in numerical calculations of the earthquake response. The method of analysis that they used can be used to examine pounding in both buildings and bridges. In order to accomplished to evaluate the effects that concerning pounding force during earthquake in structures, they made a comparison between linear and non-linear models. In the non-linear pounding model they produced results that showed the one-sided pounding model produces more dangerous effects than the two-sided. In their analysis they derived a mathematical equation that concerns the impact force effects in order to represent pounding model for both elastic and inelastic structures. A realistic pounding element was used for this studying and numerical simulations have demonstrated that pounding impact behaviour is not responsive to the values of the stiffness parameter. Furthermore, their experimental results for both elastic and inelastic structures in order to balance damping levels have showed that the higher deformation occurred in the elastic model. According to some observations that have been made the values of pounding force is relatively small in the inelastic structures in comparison to the elastic structures. The value codes of moderate the damping levels are controlled as compared to the actual seismic separation gap size found through the analysis of SDF structural model. The value of seismic gap is decreased considerably as the damping capacity of the pounding structural model is increased. Jankowski [14], addressed to an extent of a non-linear modelling due of earthquake that generated pounding of structural buildings, by deriving the essential fundamental mathematical expressions, involving the function and the applications of the non-linear analysis. By analysing various earthquake records, he derived appropriate mathematical expressions showing the limitation and the feasibility of a non-linear model, in anticipating values for a seismic pounding gap size as well as values for mass, elastic stiffness and damping coefficients between buildings. In his analysis of two inadequately separated buildings with different dynamic characteristics, modelled by elastoplastic multi-degree-of-freedom lumped mass models are used to simulate the functioning structural behaviour and non-linear viscoelastic impact specificity elements are applied to a model collision. The results of the study demonstrate that pounding has an indicative impact on the behaviour of structural buildings, and furthermore the results that he derived confirm the performance of the non-linear, viscoelastic model which endures to simulate the pounding phenomenon more accurately. 2.1.2 Seismic Pounding Effects between adjacent buildings In these last decades, the pounding phenomenon between closely spaced building structures can be a serious hazard especially in seismically active areas with strong ground motion. Because of that critical fact a beneficial awareness of pounding response on engineer structures and numerical formulas for calculating building separation gap size based on linear or analogous linear methods have been introduced. Abdel Raheem [14] established and achieved a tool for the inelastic analysis of seismic pounding effect between buildings. He carried out a parametric study on buildings pounding response as well as proper seismic hazard mitigation practice for adjacent buildings. Three categories of recorded earthquake excitation were used for input. He studied the effect of impact using linear and nonlinear contact force model for different separation distances and compared with nominal model without pounding consideration. Therefore the results of these studies lean on the stimulation characteristics and the relationship between the buildings fundamental period. Furthermore because pounding produces acceleration and shear in various story levels that are greater than those from the no pounding case. Westermo [16] suggested, in order improving the earthquake response of structures without adequate in-between space of the structures, to linking buildings by beams, which can carry the forces between the structures and thus annihilating collisions. Anagnostopoulos [6] analysed the effect of pounding for buildings under strong ground motions by a simplified single-degree-of-freedom (SDOF) model. Miller and Fatemi [17] explored in to an extent the phenomenon of pounding-impact force, of adjacent buildings subjected to harmonic motions by the vibroimpact concept. Maison and Kasai [18] modelled the buildings as multiple-degree-of-freedom systems and analysed the response of structural pounding with different types of idealizations. Papadrakakis et al. [19] studied the pounding response of two or more close separated buildings based on the Lagrange multiplier approach by which the geometric compatibility conditions due to proximity are constrained. A three-dimensional model developed for the simulation of the pounding behaviour of adjacent buildings is presented by Papadrakakis et al. [20]. In the evaluation of building separation, Jeng et al. [18] estimated the minimum separation distance required to avoid pounding of adjacent buildings by the spectral difference (SPD) method. Kasai et al. [4] extended Jengs results and proposed a simplified rule to predict the inelastic vibration phase of buildings based on the numerical results of dynamic time-history analyses. Anagnostopoulos and Spiliopoulos [7] examined the behaviour of common pounding between adjacent buildings in city blocks to several strong earthquakes. In the study, the buildings were idealized as lumped-mass, shear beam type, multi-degree-of-freedom (MDOF) systems with bilinear force deformation characteristics and with bases supported on translational and rocking spring dashpots. Collisions between adjacent masses can occur at any level and are simulated by means of viscoelastic impact elements. They used five real earthquake motions to study the effects of the following factors: building configuration and relative size, seismic separation distance and impact element properties. It was found that pounding can cause high over stresses, mainly when the colliding buildings have significantly different heights, periods or masses. They suggest a possibility for introducing a set of conditions into the codes, combined with some special measures, as an alternative to the seismic separati on requirement. Figure 2.1.2-2 on the left there is a finite element mathematical model and on the right shows the elevation view of a 2 different height building with the separation gap size [14] Abdel Raheem 2006; 2.1.3 SEISMIC POUNDING EFFECT AND RESTRAINERS ON SEISMIC RESPONCE OF MULTIPLE-FRAME BRIDGES DesRoches and Muthukumar [22] used analytical illustrations to check out, the factors and the parameters affecting the worldwide reaction and behaviour of a multiple-frame bridge as a result of pounding of adjacent frames. They have conducted parameter studies of one-sided and two-sided pounding, to dispose the effects of frame stiffness ratio, ground motion characteristics, frame yielding, and restrainers on the pounding behaviour of bridge frames. They showed that the addition of restrainers has a minor effect on the one-sided pounding response of highly out-of-phase frames. It is determined that the most important parameters are the frame period ratio and the characteristic period of the ground motion. The current study explores the effect that pounding impact-force and restrainers have on the worldwide appeal of bridge frames in a multi-frame bridge. They used investigations of two-sided pounding using MDOF models, which showed a favourable post impact response for the flexible f rame and a detrimental effect for the stiff frame demand, for all period ratios. The results from both one-sided and two-sided impact reveal that the response of bridge frames due to pounding, irrespective of the ground motion period ratio, thus validating the recommendations suggested by Caltrans. Current recommendations by Caltrans for limitations in frame period ratios to reduce the effects of pounding are evaluated through an example case. The effect of restrainers on the pounding response of bridge frames is evaluated. The results show that restrainers have very little effect on the demands on bridge frames compared with pounding. 2.1.4 GIRDER POUNDING ON BRIDGES Hao and Chouw [23] introduced a new design principle for anticipating Effect of Structural Pounding During Seismic Events Effect of Structural Pounding During Seismic Events Abstract This project entitled aims at the investigation of the effect of structural pounding to the dynamic response of structures subject to strong ground motions. In many cases structural pounding during earthquake may result in considerable and incalculable damages. It usually need to be accounted for in the case of adjacent structures, bridges, base isolated buildings, industrial and port facilities, and in ground pipelines. The phenomenon of that impact force pounding has been noted by researchers and engineers over the past several decades. As we see through dull historical strokes and performance, in different investigations of past and recent earthquakes damage have illustrated several cases of pounding damage such as those that have occurred in the Imperial Valley (May 18, 1940), the Sequenay earthquake in Canada (1988), Kasai Maison (1991), the Cairo earthquake (1992), the Northridge earthquake (1994), California (1994), Kobe, Japan (1995) Turkey (1999), Taiwan (1999) and Bhuj, Ce ntral Western India (2001). Some of the most memorable seismic events were in the 1972 Managua earthquake, when the five-storey Grant Hotel suffered a complete collapse, also in the 1964 Alaska earthquake, the 14-storey Anchorage Westwood hotel pounded against its low rise ballroom and the most recently extent of pounding in Mexico City in 1985 confirmed this as a major problem. Those all evidences have continued to illustrate the annihilation of earthquakes, with devastation of engineered in both buildings and bridges structures. Amongst the feasible structural destructions, seismic produced pounding has been frequently distinguished in numerous earthquakes, as a result this phenomenon plays a key role to the structures. As engineers, we have a responsibility to prevent it or take the necessary steps to mitigate it for the future constructions by considering the properties that affect and led pounding to occur. In order to examine the effect of the various parameters associated wit h pounding forces on the dynamic response of a seismically excited structure, a number of simulations and parametric studies have been performed, using SAP2000. By more precise investigations that have been done from professional earthquake investigators and engineers pounding produces acceleration and shear at various story levels. Also, significantly depends on the gap size between superstructure segments, which we will examine later on in the project. The main aim of the project is to conduct a detailed investigation on pounding-involved response structure during a seismic event as well as observed the structural behaviour as the result of ground motion excitation by examine the properties that affect pounding and determine the solutions and the mitigations that we have to take into account before we construct a structure in order to avoid future disasters. INTRODUCTION 1.1 Seismic Pounding effect (Overview) Looking throughout the time, investigations and observations of the effects of historical earthquakes have demonstrated that many structures are susceptible to significant damage which may lead to collapse. Numerous devastating earthquakes have hit various seismically active regions. Some investigations that have been followed after those seismic events are distinguished fact providing that, an earthquake within the range of six is capable of creating and generating incalculable and irreversible damages, of both buildings and bridges. Those seismic losses have further consequences, most likely to present economical problem to the community hit. The main target of most seismic excitations are, the primary frequencies of rigid buildings between the ranges of low to medium height, resulting by this in significant accumulations of soil acceleration. Also, addition to this is the causing the presence of the inevitable enduring seismic loads in engineered structures, creating inflexible re sponses. In recent years it becomes more urgent need to minimize seismic damage not only to avoid structures failures but especially in crucial building facilities such as hospitals, telecommunications etc. as well as the protection of the critical equipment that is accommodated by those buildings. (a)barrier rail damage (Northridge earthquake 1994) (b)Connector collapse (Northridge earthquake 1994) In seismically active areas the phenomenon of pounding may need to be accounted for, in the case of closely spaced structures to avoid extensive damages and human losses. The phenomenon of that impact force-pounding has been noted by earthquake investigators over the past several decades when the presence of pounding occurred into an extent. Looking throughout the time, some historical performance of pounding has been denoted, different investigations of past and recent earthquakes damage have illustrated several cases of pounding damage such as those that have occurred in the Imperial Valley (May 18, 1940), California (1994) the Northridge earthquake, Kobe, Japan (1995) and etc. in both engineered structures, buildings and bridges. One of the most remarkable example of pounding-involved destruction resulted from interactions between the Olive View Hospital main building and one of its independently standing stairway towers during the San Fernando earthquake of 1971. The extent of po unding was recently observed in Mexico City in 1985, which then it follows the most recent one in Central Western India (2001). Considerable pounding was observed at sites over 90 km from the epicentre thus indicating the possible catastrophic damage that may occur during future earthquakes having closer epicentres. Is remarkable to denote that pounding of adjacent buildings could have defective damage such as adjacent structures with different dynamic characteristics which vibrate out of phase and there is inadequate separation gap or energy diffusion system to board the relative moderate motions of adjacent buildings. (a)Collapse of a department store building (Northridge earthquake 1994) (b)Collapse of the first story of a wooden residential building (Northridge earthquake 1994) Several researchers considered the topic of pounding between adjacent buildings (Anagnostopoulos 1988; Maison Kasai, 1990; Papadramakis et al, 1996) with proving or deriving mathematical expression in order to evaluate and calculate the pounding force, by using experimental procedures. But few people have actually addressed the topic of pounding between adjacent buildings (Tsai, 1997; Malhotra, 1997; Matsagar Jangid, 2003; Komodromos et al 2007) for which the behaviour and the requirements differ from the conventional structures. Likewise, those projects are limited especially to the study and investigation of pounding between adjacent buildings and based isolated buildings without investigating the case of conflict with neighbouring buildings and the resulting of great deformations of the superstructure. In the past engineers couldnt prevent the pounding due to some factors such as the past seismic codes did not give explicit guidance, because of this and due to particular economical factors and considerations, that are concerning the maximum land usage requirements, especially in the high density populated areas of cities pounding was unavoidable. Due to that, we are able to identify and investigate many buildings in global system which are already been built in contact or overmuch close to another that could easily cause them to suffer from pounding damage in future earthquake strikes. A large rupture is controvertible from both aspects. The overcrowded construction system in many cities complements a dominant apprehension for seismic pounding damage. For these major reasons, it has been comprehensively acquired that pounding is a disastrous phenomenon that should be anticipated or mitigated. Acceleration range will guidance in many cases to quake activities which are appreciably h igher than designed by the design codes that have been used up to now. The most affordable and easy active way for mitigating pounding effects and diminishing pounding damage, is to consider enough separation gap size between close adjacent structures, this causing difficulties to be accomplished, owing to the detailing engineered work that supposed to be done and the high cost of land in this present time. A flipside to the seismic separation gap precaution in the construction design is to reduce the effect or pounding force through devaluating lateral motion, some researchers involved in extent with lateral ground motions due to pounding such as (Kasaiet al. 1996, Abdullah et a.2001, Jankowski et al 2000, Ruangrassamee Kawashima 2003, Kawashima Shoji 2000). This procedure can be accomplished by joining adjacent structures at critical locations of the supports so that their motion could be in-phase with one another or by lessening the pounding buildings damping capacity by means of passive structural control of energy dissipation system. 1.2 Pounding force and impact element Various impact elements are usually used to illustrate the pounding between adjoining construction buildings or bridge structures. Pounding between two conflicting structures, is often simulates by using contact force-based impact models such as the linear spring, Kelvin-Voigt element and Hertz contact model element, and additionally the restitution momentum-based stereo mechanical method. (a) (b) (c) Figure 1.2.1 shows the pounding problem in: (a) bridge structures [1] S. Mithikimar and R. DesRoches 2006; (b) adjacent buildings with link elements [2] V. Annasaheb Matsagar and R. Shyam Jangid 2005; (c) adjacent building with gap size structures [1] S. Mithikimar and R. DesRoches 2006; Also another view of pounding effect beyond that in buildings is on the bridges. Many damages during strong earthquakes have occurred in bridge due to pounding between the girders when the gap is not sufficient. From many experimental studies that have been made showed that pounding damage of a bridge can have severe after-effects as it has been observed in many major earthquakes, such as the 1994 Northridge earthquake etc. As we can see from our daily routine bridges belong to one of the important lifeline systems, their proper function play major role in both our life and in the culture, especially after a devastating earthquake in order to survive and/or recovery. According to some studies [3] Chouw and Hao (2003) and [4] Hai SUI et al. (2004) showed that gap size in the bridges plays the major key role for a bridge to survive under a pounding impact force. The examined the gap size and the outcomes showed that a smaller gap size can expect larger pounding force; therefore the possibility of damage of bridge decks is higher. So on in general designs a small gap should be avoided, if is possible. Moreover according to their experiment the results showed that friction device can decrease pounding impact force that works in different earthquakes. a) Multiple-pier bridge model [4] H. SU, et al 2004; b) Two Single degree of freedom model [4] H. SU, et al 2004; An adequate gap size can contribute to the reduction of pounding effect, but nevertheless in real life the gap size for the designs is unavoidable and due to the limited space that we have to build the design the gap size end up to has smaller values. And thus we resort to other solutions in order to reduce the pounding effect, such as the friction device and bumpers (steel spring with viscous damper). Moreover friction device is much more practical and effective than bumpers. Bumpers can avoid the immediate damage but they cannot reduce the pounding force between the bridge girders, in the other hand friction device can be applied to any earthquake and also is less sensitive to various ground movements. Linear spring element The linear spring element is the easiest and simplest contact element that used to model impact. When the gap between the adjoining structures adjournments, the spring take effect and is presentational of the force established in the meanwhile of impact force. According to Maison Kasai [5] (1992) have used this model widely, to study further analyse pounding between adjacent buildings. Nonetheless, the linear spring cannot resolve the energy dissipation during impact. The linear spring element illustrated in Figure 1.2.3(a). The Kelvin-Voigt Element The Kelvin-Voigt element can be described by a linear spring in parallel with a damper, as depicted in Figure 1.2.3(b), this model has been used in some studies [6] Anagnostopoulos, 1988; [7] Anagnostopoulos and Spiliopoulos, 1992; [8] Jankowski 2005; The linear spring illustrates the force during impact and the damper accounts for the energy dissipation during impact and is mostly used. The damping coefficient (ck) can be related to the coefficient of restitution (e), by equating the energy dissipations during impact, following the form of equations below: Where, and Kk is the stiffness of the contact spring, and m1, m2 are the masses of the colliding bodies. Hertz contact law Additionally, a non linear spring based on Hertz contact law can be used to model impact, as depicted in Figure 1.2.3(c). Nonetheless, the Hertz contact law is a characteristic representing of the static contact between elastic bodies and fails to contain energy loss during impact. The impact force can be expressed in the form of the equation below: Where R is the impact stiffness parameter that depends on the material properties of the colliding structures and the contact surface geometry, g is the at-rest separation and n is the Hertz coefficient. The use of the Hertz contact law has an intuitive appeal in modelling pounding, since one would expect the contact area between the colliding structures to increase as the contact force increases, leading to a non-linear stiffness described by the Hertz coefficient n which typically is taken ad 1.5. Several analysts have adopted this approach, including [9] Davis 1992; [10] Pantelides and Ma 1998; [11] Chau and Wei 2001; and [3] Chau et al. 2003; More, for pounding simulation we can also meet the Hertzdamp model, which is a contact model based on the Hertz contact law and using a non linear hysteresis damper. According to experimental theories, for low peak ground acceleration levels, Hertz model produces sufficing results and the Hertzdamp model can be used in advance for moderate and high peak ground acceleration levels (PGA). The contact element approach has its limitations, with the exact value of spring stiffness to be used, being unclear. Uncertainty in the impact stiffness arises from the unknown geometry of the impact surfaces, uncertain material properties under loading and variable impact velocities. The contact spring stiffness is typically taken as the in plane axial stiffness of the colliding structure (Maison and Kasai, 1990). Another reasonable estimate is twenty times the stiffness of the stiffer structure [6] Anagnostopoulos, 1988; However, using a very stiff spring can lead to numerical convergence difficulties and unrealistically high impact forces. The solution difficulties arise from the large changes in stiffness upon impact or contact loss, thus resulting in large unbalanced forces affecting the stability of the assembled equations of motion. (a) Linear spring element (b) Kelvin Voigt Element (c) Hertz non-linear spring element Figure 1.2.3: Various impact models and their contact force relations [12] Thomas G.Mezger 2006; 1.3 Method of Seismic Analysis 1.3.1 Non-linear Dynamic Analysis Non-linear Dynamic analysis involves step-by step in time integration of the non-linear governing equations of motion, a powerful analysis that can evaluate any given seismic event motion. An earthquake accelerogram is correlated and the consistent response-history of a structural model during seismic events is evaluated. Computer softwares have been designed for these kinds of purposes. Sap can utilized a non-linear dynamic analysis for both linear elastic and non-linear inelastic material response, using step by step integration methods. Is a suitable computer program that is able to evaluate and analyze the response of a two-dimensional and a three-dimensional non-linear structure taking as an input the accelerogram component of an Earthquake? This program will be used to analyse our structural model and to produce a real time of time-history displacement. In a nonlinear dynamic procedure the building model followed static procedures incorporating directly the inelastic material r esponse using in general finite elements. Because this program is using step-by step integration method of analysis the response of the structure, is one of the most sophisticated analysis procedure for predicting forces and displacements under seismic input. However, the calculated response can be very sensitive to the characteristics of the individual ground motion used as seismic input; therefore several time-history analyses are required using different ground motion records. The main value of nonlinear dynamic procedures has the objective to simulate the behaviour of a building structure in detail. 1.4 Main Objectives of this project The main focus of this project is the development of an analytical model that pounding force will present based on the classical impact theory by using parametric study to identify the most important parameters that affecting pounding. Those factors that give arise to that impact force, therefore investigate of the different practical types of structures that pounding can be occurred. The main objective and scope of this study are, to explore the global response of buildings structures when the pounding effects take place under seismic events, therefore to review the main outcomes of the literature and how the impact theory come across to the practical cases. Create a structural modelling and perform a non linear time history analysis on it. Examine the realistic model of pounding that we will create if it satisfies the properties in order for the structure to work. Determine the relative importance of the dynamic characteristics of pounding. Dynamic analysis will be carried out on the model structure to observe the displacement of the structure due to earthquake excitation. When we examine the main structure we are mainly concerned with displacement, velocity and acceleration, the general dynamic behaviour of the structure under the action of dynamic loads such as earthquake lateral loads. For the purpose of the project appropriate computer software will be used for its purposes (e.g. SAP2000). Creation and versatile of the model, accomplishment of the analysis, and checking and breakthrough of the design must be all done through this interface. Graphical displays of the results, including the real-time of time-history displacements will be easily produced by the use of that software. At the end of that modelling analysis by gathering all the necessary and useful outcomes and explored in deep the main parameters derived by this, the conclusion and results of what we have to adopt as engineering before retrofitting a structure. The appropriate structural parameters are the separation gap size between adjacent structures (storey mass, structural stiffness and yield strength etc.), the dynamic behaviour of a damped multi-degree of freedom bridge system separated by an expansion joint, considering the limited width of clearance around a seismically isolated buildings, that pounding can cause high over stresses when the colliding buildings have different height, periods or masses and the isolators in bridge structures are effective in mitigating the induced seismic forces, cable restrainers etc. Engineers should adopt those realistic facts before they construct new structures in order to succeed future sustainability of the structures and avoiding by this the impact phenomenon of pounding. Accomplish to mitigate the phenomenon of pounding in order to prevent future collisions and/or engineering disasters when seismic events occur. REVIEW OF LITERATURE 2.1 Practical Cases Pounding-impact force generated by earthquakes between different analytical structure models may provoke extensive damage and in general most of the times the result of that force is not pleasant, it may lead the structure to a total collision as it can be seen from different practical cases. Pounding problem is phenomenon that has been observed during earthquakes and in accordance to ground motions, and has been extensively investigated by various researchers that have used a variety of impact analytical models. Because of the importance of what pounding will have as a result of different engineering structures, attracted the attention of several scientists and analyzers? This absorption is a consequence fact of a plenty growing amount of evidence, which can be found in reports and journals, which have been created after dominant exceeding earthquakes. Demonstrating, the power of that certain impact force which may cause considerable damage. The conclusions and results of successive series of various numerical, integrated analytical and experimental studies have been conducted using individual structural models and administering different models of practical cases confirm that pounding, due to constraining additional impact forces, may result in damage as well as significantly increase the structural response. Moreover, there are many practical case histories of engineered buildings with different dynamic properties and characteristics, which have been constructed under the old earthquake resistant design codes. Analogous conditions concern also bridge constructions. When a structure is under earthquake vibrations will move according to ground motions. These vibrations can be entirely exaggerated, creating at the same time stresses and deformations throughout the structure. Evaluation of methods can be carry out in engineering practise to estimate the parameters that give a rise to pounding. The accuracy and the ability of computational appliance have increased a lot this century by helping us evaluate the seismic structural response of structure, a variety of softwares computing programs have been designed for those purposes, and can accomplished to calculate the dynamic seismic response of a structure which help engineers mitigate pounding effects in structure by avoiding future disaster s . Linear and nonlinear models are realistic pounding models that have been used for studying the performance of a structural system under the mode of structural pounding effect under seismic events. Significance to notice in seismically active areas the serious hazard that pounding can cause and in what practical cases does it occurs by review of some critical and enlightened journals and reports, according to history performance of an exceeding major earthquakes. Also a time history analysis is a dynamic tool for the investigation of a structural seismic enforcement. Because of all the above reasons, investigations have been carried out on pounding mitigation in order to improve the seismic response. 2.1.1 Linear and non-linear pounding of structural systems Pantellides and Ma [13] examined by experimental procedures, the dynamic response of a damped single degree-of-freedom structural model during a seismic event. They analysed the structural behaviour of SDF with both elastic and inelastic structural impact response by using realistic parameters for the pounding model in numerical calculations of the earthquake response. The method of analysis that they used can be used to examine pounding in both buildings and bridges. In order to accomplished to evaluate the effects that concerning pounding force during earthquake in structures, they made a comparison between linear and non-linear models. In the non-linear pounding model they produced results that showed the one-sided pounding model produces more dangerous effects than the two-sided. In their analysis they derived a mathematical equation that concerns the impact force effects in order to represent pounding model for both elastic and inelastic structures. A realistic pounding element was used for this studying and numerical simulations have demonstrated that pounding impact behaviour is not responsive to the values of the stiffness parameter. Furthermore, their experimental results for both elastic and inelastic structures in order to balance damping levels have showed that the higher deformation occurred in the elastic model. According to some observations that have been made the values of pounding force is relatively small in the inelastic structures in comparison to the elastic structures. The value codes of moderate the damping levels are controlled as compared to the actual seismic separation gap size found through the analysis of SDF structural model. The value of seismic gap is decreased considerably as the damping capacity of the pounding structural model is increased. Jankowski [14], addressed to an extent of a non-linear modelling due of earthquake that generated pounding of structural buildings, by deriving the essential fundamental mathematical expressions, involving the function and the applications of the non-linear analysis. By analysing various earthquake records, he derived appropriate mathematical expressions showing the limitation and the feasibility of a non-linear model, in anticipating values for a seismic pounding gap size as well as values for mass, elastic stiffness and damping coefficients between buildings. In his analysis of two inadequately separated buildings with different dynamic characteristics, modelled by elastoplastic multi-degree-of-freedom lumped mass models are used to simulate the functioning structural behaviour and non-linear viscoelastic impact specificity elements are applied to a model collision. The results of the study demonstrate that pounding has an indicative impact on the behaviour of structural buildings, and furthermore the results that he derived confirm the performance of the non-linear, viscoelastic model which endures to simulate the pounding phenomenon more accurately. 2.1.2 Seismic Pounding Effects between adjacent buildings In these last decades, the pounding phenomenon between closely spaced building structures can be a serious hazard especially in seismically active areas with strong ground motion. Because of that critical fact a beneficial awareness of pounding response on engineer structures and numerical formulas for calculating building separation gap size based on linear or analogous linear methods have been introduced. Abdel Raheem [14] established and achieved a tool for the inelastic analysis of seismic pounding effect between buildings. He carried out a parametric study on buildings pounding response as well as proper seismic hazard mitigation practice for adjacent buildings. Three categories of recorded earthquake excitation were used for input. He studied the effect of impact using linear and nonlinear contact force model for different separation distances and compared with nominal model without pounding consideration. Therefore the results of these studies lean on the stimulation characteristics and the relationship between the buildings fundamental period. Furthermore because pounding produces acceleration and shear in various story levels that are greater than those from the no pounding case. Westermo [16] suggested, in order improving the earthquake response of structures without adequate in-between space of the structures, to linking buildings by beams, which can carry the forces between the structures and thus annihilating collisions. Anagnostopoulos [6] analysed the effect of pounding for buildings under strong ground motions by a simplified single-degree-of-freedom (SDOF) model. Miller and Fatemi [17] explored in to an extent the phenomenon of pounding-impact force, of adjacent buildings subjected to harmonic motions by the vibroimpact concept. Maison and Kasai [18] modelled the buildings as multiple-degree-of-freedom systems and analysed the response of structural pounding with different types of idealizations. Papadrakakis et al. [19] studied the pounding response of two or more close separated buildings based on the Lagrange multiplier approach by which the geometric compatibility conditions due to proximity are constrained. A three-dimensional model developed for the simulation of the pounding behaviour of adjacent buildings is presented by Papadrakakis et al. [20]. In the evaluation of building separation, Jeng et al. [18] estimated the minimum separation distance required to avoid pounding of adjacent buildings by the spectral difference (SPD) method. Kasai et al. [4] extended Jengs results and proposed a simplified rule to predict the inelastic vibration phase of buildings based on the numerical results of dynamic time-history analyses. Anagnostopoulos and Spiliopoulos [7] examined the behaviour of common pounding between adjacent buildings in city blocks to several strong earthquakes. In the study, the buildings were idealized as lumped-mass, shear beam type, multi-degree-of-freedom (MDOF) systems with bilinear force deformation characteristics and with bases supported on translational and rocking spring dashpots. Collisions between adjacent masses can occur at any level and are simulated by means of viscoelastic impact elements. They used five real earthquake motions to study the effects of the following factors: building configuration and relative size, seismic separation distance and impact element properties. It was found that pounding can cause high over stresses, mainly when the colliding buildings have significantly different heights, periods or masses. They suggest a possibility for introducing a set of conditions into the codes, combined with some special measures, as an alternative to the seismic separati on requirement. Figure 2.1.2-2 on the left there is a finite element mathematical model and on the right shows the elevation view of a 2 different height building with the separation gap size [14] Abdel Raheem 2006; 2.1.3 SEISMIC POUNDING EFFECT AND RESTRAINERS ON SEISMIC RESPONCE OF MULTIPLE-FRAME BRIDGES DesRoches and Muthukumar [22] used analytical illustrations to check out, the factors and the parameters affecting the worldwide reaction and behaviour of a multiple-frame bridge as a result of pounding of adjacent frames. They have conducted parameter studies of one-sided and two-sided pounding, to dispose the effects of frame stiffness ratio, ground motion characteristics, frame yielding, and restrainers on the pounding behaviour of bridge frames. They showed that the addition of restrainers has a minor effect on the one-sided pounding response of highly out-of-phase frames. It is determined that the most important parameters are the frame period ratio and the characteristic period of the ground motion. The current study explores the effect that pounding impact-force and restrainers have on the worldwide appeal of bridge frames in a multi-frame bridge. They used investigations of two-sided pounding using MDOF models, which showed a favourable post impact response for the flexible f rame and a detrimental effect for the stiff frame demand, for all period ratios. The results from both one-sided and two-sided impact reveal that the response of bridge frames due to pounding, irrespective of the ground motion period ratio, thus validating the recommendations suggested by Caltrans. Current recommendations by Caltrans for limitations in frame period ratios to reduce the effects of pounding are evaluated through an example case. The effect of restrainers on the pounding response of bridge frames is evaluated. The results show that restrainers have very little effect on the demands on bridge frames compared with pounding. 2.1.4 GIRDER POUNDING ON BRIDGES Hao and Chouw [23] introduced a new design principle for anticipating

Schizophrenia :: essays research papers

Schizophrenia is a class of disorders characterized by fundamental disturbances in thought processes, emotion, or behavior. It is also known as a "split mind"; the person is in a world that has nothing to do with everyday experiences. One to one and a half percent of the U.S. population will be diagnosed with it sometime over the course of their lives. Schizophrenia has a pattern of unique and predictable symptoms. There are two main types of symptoms: positive and negative symptoms. The positive symptoms are delusions or hallucinations; negative symptoms are deficits in behavior or an inability to express emotion. But what exactly are these symptoms and are they easy to detect? The more obvious types of symptoms are the positive. One characteristic that is often experienced is delusions, which are known as thoughts with meanings that are unrealistic. For example, people with this disorder tend to believe that they are someone else in disguise such as Elvis or Jesus. Another type of delusion is the delusion of grandeur, which is when an individual believes that they are more important than they actually are. A less common but very real type of delusion is a delusion of persecution, which is when an individual is convinced that others are plotting against him. But even more severe is perceptions known as hallucinations. Hallucinations are perceptions that can not possibly be real because there is nothing external to support them; however, to the person affected, they can be heard, seen, or even felt. Some individuals may see objects change shape or size, which is not very unusual for someone with schizophrenia. On some occasions, individuals claim to hear voices in their heads, telling them to do or say certain things. These voices appear to be so real, that in some instances individuals where known to have committed suicide because that's what the voice told them to do. Less obvious than the positive symptoms but equally serious are the negative symptoms. It is very common for a person to show flat affect, which means they show little or no emotional reaction. If someone shows a person with this disorder an extremely funny movie or a very sad picture, they are unlikely to even smile or shed a tear. People with schizophrenia also refuse to participate in basic everyday activities. They may refuse to eat or wash themselves. Some other symptoms that are less common are disorganized speech and catatonia.

I: The Better Part of Justice

Through two separate cases and decisions respecting the affirmative action policy at the University of Michigan, the Supreme Court offered two opposite opinions on the same question—striking down the university’s undergraduate College of Literature, Science and the Arts (LSA) affirmative action policy (Gratz v. Bollinger, 6-3) in 2003 and upholding the University of Michigan Law School’s (UMLS) affirmative action policy (Grutter v. Bollinger, 5-4) at the same time. However, the specific reasoning for each of the two different opinions explains the court’s seemingly contradictory rulings. In the Grutter v. Bollinger decision of this reverse discrimination challenge, the Supreme Court agreed that the State had a compelling interest in an ethnically diverse student body at UMLS which afforded applicants who are ethnic minorities a greater regard in their candidature for acceptance to the law school. UMLS considered candidates holistically and did not award them points solely on the basis of their ethnic minority status. The Court held that the practice is not prohibited by the U.S. Constitution and was in keeping with the narrow tailoring set forth by Regents of the University of California v. Bakke, 438 U.S. 265 (1978) for how affirmative action admission policies might be devised when informed by the Fourteenth Amendment. Moreover, the Court said that the affirmative action policy ought not to be permanent and should be replaced by a color-blind policy after twenty-five years at which time affirmative action in admissions should no longer be necessary. Concerning Gratz v. Bollinger, the Court’s opinion was opposite the Grutter case finding that the affirmative action policy used by LSA was a violation of the Fourteenth Amendment. Unlike UMLS, LSA automatically awarded points to ethnic minority applicants on the basis of their minority ethnicity alone as opposed to the special consideration of each candidate as an individual like UMLS did. Thus, the Court sided with the plaintiffs against Bollinger because of the automatic nature of the preferential treatment of ethnic minority candidates for no other considerations than race. This was viewed as a blatant violation of the U.S. Constitution because the numeric system was not narrowly tailored and failed to meet the standard of strict scrutiny. It is clear from these two cases and Supreme Court decisions that affirmative action as a means to student diversity was not in contention for the Court but rather the administration of any such policy. The how was the real heart of the matter and not whether such a policy was needed at this point in time in American history. As in almost any case, it is the details that ultimately determine the court’s as well as the public’s opinion on an issue before them. II: The Affirmative Action Controversy Ironically, Boatright’s â€Å"No† (p. 179) column against affirmative action on the whole were more compelling arguments in support of why the U.S. government should implement affirmative action in employment and in education than the â€Å"Yes† (p. 178) column favoring the policy. Although Justice O’Connor appealed to research in social science in her composition of the majority decision, like the â€Å"Yes† column arguments seem to do, the logical thinking of the â€Å"No† column appeals to reason and justice. When relevantly compared to the almost four centuries of societal and institutional discrimination and prejudice, the view that affirmative action promotes a victim mindset is an incompetent argument and becomes fallacious. The logical argument is that the very maltreatment itself is the greatest cause of any sense of victim identity as it would be in a criminal case (e.g., rape, assault, mugging, etc.). Contrarily, affirmative action is likely to foster a sense of relief or appreciation like when the criminal that victimized someone is caught. Furthermore, special consideration in getting a foot in the door of a school or job does not ‘taint’ the work or confidence of individuals—as we see from the privileged access white ethnics have enjoyed in the Americas since the 1600s—who understand the difference between access and performance and are often anxious to prove their worth for which the lack of access is a barrier. Once access is granted to those it has been denied, they desire to â€Å"succeed or fail on an equal basis† (p. 179) just as any other privileged class claims to desire. Although racial tensions may arise, it is a stretch of the imagination to argue that affirmative action is somehow worse than racial prejudice and discrimination respecting racial tensions or anything else. One day the pernicious effects of racial discrimination may well be in the past like American slavery is but they are not past yet. Sparing white ethnics from reverse discrimination sometimes is inadequate as a defense for maintaining the status quo in the quixotic hope that institutional prejudice and discrimination against ethnic minorities will someday just fade away. Certainly, the abundant evidence of discrimination is comparable to the special preferences afforded war veterans, Holocaust victims, 9/11 attack victims, their families, and affected businesses as well as displaced victims of Hurricane Katrina. Like the Tsunami victims in 2004 half the world away, the U.S. government recognizes by its own actions that victims of disaster, domestically or internationally, require some type of preferred assistance to overcome the devastating effects of something inflicted upon them. Victims of the long-lasting effects and consequences of the peculiar institution of slavery in the U.S. are just as deserving of special consideration as victims of events or forces that warrant special attention from the FEMA or the Red Cross or any number of other governmental and non-governmental organizations domestically and internationally which are dedicated to providing assistance to affected persons with particular regard to race. For example, these organizations would not locate themselves in England but in Ethiopia or Indonesia or Haiti. Moreover, because the aim of affirmative action is to increase ethnic diversity in colleges and universities and access to employment it does not explicitly quash the special privileges enjoyed by white ethnics with regard to access to higher education or gainful employment. The idea that race-neutral criteria can work, or are even just in this job/school context given the longstanding social history of the condition, to correct the tremendous inequities caused and maintained by institutional discrimination against ethnic minorities is unrealistic at best and underhanded in the least. It essentially is an argument for the status quo because it offers no compelling alternative public policy by which the object of ending racial inequity in schools and the labor market is begun. It would restore the privileges of the ethnic majority unabated while relegating the ethnic minority(ies) of the nation to feed on the scraps from the table of the descendants of their former slave masters. It takes no stretch of the imagination to see how such a non-policy policy would be the very framework of wider racial tensions on par with the widening gap between rich and poor in the United States. References Grutter v. Bollinger, 539 U.S. 306 (2003) and Gratz v. Bollinger, 539 U.S. 244 (2003). Writs of Certiorari to the United States Court Of Appeals for the Sixth Circuit (Nos. 02-241, 02-516). Retrieved April 29, 2007, from http://www.oag.state.ny.us/press/2003/feb/grutter_vs_bollinger.pdf