Income statements transparency and firms' characteristics of companies listed on the Bursa Malaysia
INTRODUCTION
Financial statements should always provide reliable information to assist users in decision making. The statement should disclose relevant, reliable, comparable and understandable information. To be understood clearly, the presentation should not be misleading. Readers should be able to understand the information presented without undue effort according to International Accounting Standards (IAS) 1. To achieve this, the annual reports should contain full disclosure and higher level of transparency. As Thompson and Yeung (23) stressed that for a company to be transparent, disclosure means providing a full and frank account of a company's activities. In addition, as far as corporate transparency is concerned, it should be defined as the widespread availability of relevant, reliable information about the periodic performance, financial position, investments opportunities, governance, value and risk of publicly traded firm (3).
Comprehensive disclosure of financial statement has been a world wide issue for a long decade. Malaysian market is currently promoting good corporate governance practices as a result of debacle of many big conglomerates in US as well as in Malaysia. As users of financial statement specifically income statement demanding for better disclosure of quality information and found that there are big amount of expenses portion goes to other operating expenses. The income statement is important because it reports on the operating performance of the company. The greater the transparency of income statement the more useful it will be for current and potential investor to make investment decision. In other words, the more the companies disclose, concerning the figures founding the financial statement, the greater the level of transparency. The current reform of the accounting and financial reporting in Malaysia which aims to promote transparency and to deliver high quality annual report is enhance through comprehensive disclosure. This change has contributed to the accounting standards setting and laws regarding financial reporting produced by local organizations.
The Section 167 and Ninth Schedule of the Companies Act 1965 govern the disclosure in the financial statements of companies in Malaysia. Under Section 167, states that each company must keep a proper set of books and accounts and the financial statements must contain at a minimum Profit and Loss Account, a Balance Sheet, a Cash Flow Statement and accompanying notes to the account. Schedule 9, details the item that the companies must include in the financial statements. Until the introduction of Financial Reporting Act 1997, the items in Schedule 9 represent the minimum statutory disclosure requirement for companies. It must be noted that the accounting standards issued by the Malaysian Institute of Accountants (MIA) and other professional bodies remains 'voluntary' disclosure requirement. In the case of listed companies, the regulatory agency that responsible is the Securities Commission (SC), the registrar of companies and the Central Bank of Malaysia. Their functions are to administering in public listed companies, administering companies incorporated in Malaysia and administering financial institutions respectively. This is to ensure enterprise financial reporting meeting the minimum requirements, if necessary go beyond that to achieve a fair presentation. The companies listed on the Bursa Malaysia must also meet the accounting and reporting guidelines as per issued by SC (22). Each company that going to public market should administer good corporate governance by discloses full information necessary to make informed users investment decisions.
The Malaysian Code of Corporate Governance (MCCG 2002) had been introduced to promote greater transparency and adopt professional business ethics as well as convey this via their annual reports. The National Annual Corporate Report Awards (NACRA) held by the collaboration of Bursa Malaysia, MIA and the MICPA to help Malaysian companies aim for the greatest standards in annual reporting. Study of disclosures begins with research done by Cerf (5). He constructed disclosure index by specifying and weighting some related items which might appear in annual reports. The index scores were positively correlated with firm characteristics namely asset size, number of shareholders and profitability (21). Buzby (4) was consistent with other researcher but add listing status as one of the variable to explain disclosure level.
Disclosures indexes tend to based upon lists of selected items if accounting information which may be disclosed in corporate annual reports and seek to measure the extent of disclosure by using numerical weights on items of accounting information. Extensive accounting literature relating to the use of disclosure indexes by way of measure the quality of information and it is vary among different studies. Inchausti (13) reported that in some studies, only voluntary information were considered (7), (9), (19) whilst in other studies rating for both compulsory and voluntary items was being included in an index (5), (6), (8). Studies also differ in the aspects of items included in index from 17, Barret (1), 39 Buzby (4) and 224, Cooke (8). In some studies, they compared the transparency or disclosure of accounting information in cross-countries (2), (3).
Affichage des articles dont le libellé est Technology. Afficher tous les articles
Affichage des articles dont le libellé est Technology. Afficher tous les articles
mercredi 28 octobre 2009
Design and development of sensor based traffic light system
Design and development of sensor based traffic light system
Abstract: The main object of this study was to design and implement a suitable algorithm and its simulation for an intelligent traffic signal simulator. The system developed is able to sense the presence or absence of vehicles within certain range by setting the appropriate duration for the traffic signals to react accordingly. By employing mathematical functions to calculate the appropriate timing for the green signal to illuminate, the system can help to solve the problem of traffic congestion. The simulation of the algorithm of the traffic signal system was done using MATLAB software. Hardware simulation tests were successfully performed on the algorithm implemented into a controller. The new timing scheme that was implemented promises an improvement in the current traffic light system and this system is feasible, affordable and ready to be implemented especially during peak hours. A countdown timer interfacing according to the traffic system using Lab VIEW software was also created.
Key words: Traffic signal system, sensor based traffic light system, traffic congestion
INTRODUCTION
Many traffic light systems operate on a timing mechanism that changes the lights after a given interval. An intelligent traffic light system senses the presence or absence of vehicles and reacts accordingly. The idea behind intelligent traffic systems is that drivers will not spend unnecessary time waiting for the traffic lights to change. An intelligent traffic system detects traffic in many different ways [1].
The older system uses weight as a trigger mechanism [2]. Current traffic systems react to motion to trigger the light changes. Once the infrared object detector picks up the presence of a car, a switch causes the lights to change. In order to accomplish this, algorithms are used to govern the actions of the traffic system. While there are many different programming languages today, some programming concepts are universal in Boolean Logic.
We need to understand the function of traffic signals so that we can improve driving habits by controlling the speed in order to reduce the number of associated traffic accidents. The more number of drivers who know about the operation of traffic signals, the less frustrated they are going to be while waiting for the lights to change. The main aim in designing and developing of the Intelligent Traffic Signal Simulator is to reduce the waiting time of each lane of the cars and also to maximize the total number of cars that can cross an intersection given the mathematical function to calculate the waiting time.
The traffic signal system consists of three important parts. The first part is the controller, which represents the brain of the traffic system. It consists of a computer that controls the selection and timing of traffic movements in accordance to the varying demands of traffic signal as registered to the controller unit by sensors [3]. The second part is the signal visualization or in simple words is signal face. Signal faces are part of a signal head provided for controlling traffic in a single direction and consist of one or more signal sections. These usually comprise of solid red, yellow, and green lights. The third part is the detector or sensor. The sensor or detector is a device to indicate the presence of vehicles. One of the technologies, which are used today, consists of wire loops placed in the pavement at intersections. They are activated by the change of electrical inductance caused by a vehicle passing over or standing over the wire loop. Recent technology utilization is video detection. A camera feeds a small computer that can "see" if a vehicle is present.
Experimental setup: In order to implement the Intelligent Traffic Signal Simulator, one needs to setup and assemble the hardware components and write a program to control the intelligent traffic signal simulator.
The layout of the Intelligent Traffic Signal Simulator is displayed in Figure 1. The blocks, which are labeled N1, N2, N3, E1, E2, E3, S1 and W1 are the infrared object detectors.
Hardware components: The traffic light system consists of four important components: the controller which is the brain to the system, the sensors which detect the presence of vehicles, the light emitting diodes (LED) which act as the actuator and the countdown timers which is displayed in Lab VIEW.
BASIC STAMP 2 (BS2) is used as the microcontroller of the traffic signal. The BS2, which needs to be plugged to the Board of Education (BoE), is directly attached to the computer in order to program it. The wiring for the output and input signals is done from this board. Figure 2 shows the Board of Education to which a 9V DC power is supplied. There is also a DB9 connector, that is connected to the COM port of computer using RS-232 serial cable, for BS2 programming and serial communication during runtime. Next to the BS2, there is a breadboard. The breadboard has many strips of copper, which run underneath the board in a horizontal fashion. These strips connect the sockets to each other.
Abstract: The main object of this study was to design and implement a suitable algorithm and its simulation for an intelligent traffic signal simulator. The system developed is able to sense the presence or absence of vehicles within certain range by setting the appropriate duration for the traffic signals to react accordingly. By employing mathematical functions to calculate the appropriate timing for the green signal to illuminate, the system can help to solve the problem of traffic congestion. The simulation of the algorithm of the traffic signal system was done using MATLAB software. Hardware simulation tests were successfully performed on the algorithm implemented into a controller. The new timing scheme that was implemented promises an improvement in the current traffic light system and this system is feasible, affordable and ready to be implemented especially during peak hours. A countdown timer interfacing according to the traffic system using Lab VIEW software was also created.
Key words: Traffic signal system, sensor based traffic light system, traffic congestion
INTRODUCTION
Many traffic light systems operate on a timing mechanism that changes the lights after a given interval. An intelligent traffic light system senses the presence or absence of vehicles and reacts accordingly. The idea behind intelligent traffic systems is that drivers will not spend unnecessary time waiting for the traffic lights to change. An intelligent traffic system detects traffic in many different ways [1].
The older system uses weight as a trigger mechanism [2]. Current traffic systems react to motion to trigger the light changes. Once the infrared object detector picks up the presence of a car, a switch causes the lights to change. In order to accomplish this, algorithms are used to govern the actions of the traffic system. While there are many different programming languages today, some programming concepts are universal in Boolean Logic.
We need to understand the function of traffic signals so that we can improve driving habits by controlling the speed in order to reduce the number of associated traffic accidents. The more number of drivers who know about the operation of traffic signals, the less frustrated they are going to be while waiting for the lights to change. The main aim in designing and developing of the Intelligent Traffic Signal Simulator is to reduce the waiting time of each lane of the cars and also to maximize the total number of cars that can cross an intersection given the mathematical function to calculate the waiting time.
The traffic signal system consists of three important parts. The first part is the controller, which represents the brain of the traffic system. It consists of a computer that controls the selection and timing of traffic movements in accordance to the varying demands of traffic signal as registered to the controller unit by sensors [3]. The second part is the signal visualization or in simple words is signal face. Signal faces are part of a signal head provided for controlling traffic in a single direction and consist of one or more signal sections. These usually comprise of solid red, yellow, and green lights. The third part is the detector or sensor. The sensor or detector is a device to indicate the presence of vehicles. One of the technologies, which are used today, consists of wire loops placed in the pavement at intersections. They are activated by the change of electrical inductance caused by a vehicle passing over or standing over the wire loop. Recent technology utilization is video detection. A camera feeds a small computer that can "see" if a vehicle is present.
Experimental setup: In order to implement the Intelligent Traffic Signal Simulator, one needs to setup and assemble the hardware components and write a program to control the intelligent traffic signal simulator.
The layout of the Intelligent Traffic Signal Simulator is displayed in Figure 1. The blocks, which are labeled N1, N2, N3, E1, E2, E3, S1 and W1 are the infrared object detectors.
Hardware components: The traffic light system consists of four important components: the controller which is the brain to the system, the sensors which detect the presence of vehicles, the light emitting diodes (LED) which act as the actuator and the countdown timers which is displayed in Lab VIEW.
BASIC STAMP 2 (BS2) is used as the microcontroller of the traffic signal. The BS2, which needs to be plugged to the Board of Education (BoE), is directly attached to the computer in order to program it. The wiring for the output and input signals is done from this board. Figure 2 shows the Board of Education to which a 9V DC power is supplied. There is also a DB9 connector, that is connected to the COM port of computer using RS-232 serial cable, for BS2 programming and serial communication during runtime. Next to the BS2, there is a breadboard. The breadboard has many strips of copper, which run underneath the board in a horizontal fashion. These strips connect the sockets to each other.
Design and development of sensor based traffic light system
Design and development of sensor based traffic light system
Abstract: The main object of this study was to design and implement a suitable algorithm and its simulation for an intelligent traffic signal simulator. The system developed is able to sense the presence or absence of vehicles within certain range by setting the appropriate duration for the traffic signals to react accordingly. By employing mathematical functions to calculate the appropriate timing for the green signal to illuminate, the system can help to solve the problem of traffic congestion. The simulation of the algorithm of the traffic signal system was done using MATLAB software. Hardware simulation tests were successfully performed on the algorithm implemented into a controller. The new timing scheme that was implemented promises an improvement in the current traffic light system and this system is feasible, affordable and ready to be implemented especially during peak hours. A countdown timer interfacing according to the traffic system using Lab VIEW software was also created.
Key words: Traffic signal system, sensor based traffic light system, traffic congestion
INTRODUCTION
Many traffic light systems operate on a timing mechanism that changes the lights after a given interval. An intelligent traffic light system senses the presence or absence of vehicles and reacts accordingly. The idea behind intelligent traffic systems is that drivers will not spend unnecessary time waiting for the traffic lights to change. An intelligent traffic system detects traffic in many different ways [1].
The older system uses weight as a trigger mechanism [2]. Current traffic systems react to motion to trigger the light changes. Once the infrared object detector picks up the presence of a car, a switch causes the lights to change. In order to accomplish this, algorithms are used to govern the actions of the traffic system. While there are many different programming languages today, some programming concepts are universal in Boolean Logic.
We need to understand the function of traffic signals so that we can improve driving habits by controlling the speed in order to reduce the number of associated traffic accidents. The more number of drivers who know about the operation of traffic signals, the less frustrated they are going to be while waiting for the lights to change. The main aim in designing and developing of the Intelligent Traffic Signal Simulator is to reduce the waiting time of each lane of the cars and also to maximize the total number of cars that can cross an intersection given the mathematical function to calculate the waiting time.
The traffic signal system consists of three important parts. The first part is the controller, which represents the brain of the traffic system. It consists of a computer that controls the selection and timing of traffic movements in accordance to the varying demands of traffic signal as registered to the controller unit by sensors [3]. The second part is the signal visualization or in simple words is signal face. Signal faces are part of a signal head provided for controlling traffic in a single direction and consist of one or more signal sections. These usually comprise of solid red, yellow, and green lights. The third part is the detector or sensor. The sensor or detector is a device to indicate the presence of vehicles. One of the technologies, which are used today, consists of wire loops placed in the pavement at intersections. They are activated by the change of electrical inductance caused by a vehicle passing over or standing over the wire loop. Recent technology utilization is video detection. A camera feeds a small computer that can "see" if a vehicle is present.
Experimental setup: In order to implement the Intelligent Traffic Signal Simulator, one needs to setup and assemble the hardware components and write a program to control the intelligent traffic signal simulator.
The layout of the Intelligent Traffic Signal Simulator is displayed in Figure 1. The blocks, which are labeled N1, N2, N3, E1, E2, E3, S1 and W1 are the infrared object detectors.
Hardware components: The traffic light system consists of four important components: the controller which is the brain to the system, the sensors which detect the presence of vehicles, the light emitting diodes (LED) which act as the actuator and the countdown timers which is displayed in Lab VIEW.
BASIC STAMP 2 (BS2) is used as the microcontroller of the traffic signal. The BS2, which needs to be plugged to the Board of Education (BoE), is directly attached to the computer in order to program it. The wiring for the output and input signals is done from this board. Figure 2 shows the Board of Education to which a 9V DC power is supplied. There is also a DB9 connector, that is connected to the COM port of computer using RS-232 serial cable, for BS2 programming and serial communication during runtime. Next to the BS2, there is a breadboard. The breadboard has many strips of copper, which run underneath the board in a horizontal fashion. These strips connect the sockets to each other.
Abstract: The main object of this study was to design and implement a suitable algorithm and its simulation for an intelligent traffic signal simulator. The system developed is able to sense the presence or absence of vehicles within certain range by setting the appropriate duration for the traffic signals to react accordingly. By employing mathematical functions to calculate the appropriate timing for the green signal to illuminate, the system can help to solve the problem of traffic congestion. The simulation of the algorithm of the traffic signal system was done using MATLAB software. Hardware simulation tests were successfully performed on the algorithm implemented into a controller. The new timing scheme that was implemented promises an improvement in the current traffic light system and this system is feasible, affordable and ready to be implemented especially during peak hours. A countdown timer interfacing according to the traffic system using Lab VIEW software was also created.
Key words: Traffic signal system, sensor based traffic light system, traffic congestion
INTRODUCTION
Many traffic light systems operate on a timing mechanism that changes the lights after a given interval. An intelligent traffic light system senses the presence or absence of vehicles and reacts accordingly. The idea behind intelligent traffic systems is that drivers will not spend unnecessary time waiting for the traffic lights to change. An intelligent traffic system detects traffic in many different ways [1].
The older system uses weight as a trigger mechanism [2]. Current traffic systems react to motion to trigger the light changes. Once the infrared object detector picks up the presence of a car, a switch causes the lights to change. In order to accomplish this, algorithms are used to govern the actions of the traffic system. While there are many different programming languages today, some programming concepts are universal in Boolean Logic.
We need to understand the function of traffic signals so that we can improve driving habits by controlling the speed in order to reduce the number of associated traffic accidents. The more number of drivers who know about the operation of traffic signals, the less frustrated they are going to be while waiting for the lights to change. The main aim in designing and developing of the Intelligent Traffic Signal Simulator is to reduce the waiting time of each lane of the cars and also to maximize the total number of cars that can cross an intersection given the mathematical function to calculate the waiting time.
The traffic signal system consists of three important parts. The first part is the controller, which represents the brain of the traffic system. It consists of a computer that controls the selection and timing of traffic movements in accordance to the varying demands of traffic signal as registered to the controller unit by sensors [3]. The second part is the signal visualization or in simple words is signal face. Signal faces are part of a signal head provided for controlling traffic in a single direction and consist of one or more signal sections. These usually comprise of solid red, yellow, and green lights. The third part is the detector or sensor. The sensor or detector is a device to indicate the presence of vehicles. One of the technologies, which are used today, consists of wire loops placed in the pavement at intersections. They are activated by the change of electrical inductance caused by a vehicle passing over or standing over the wire loop. Recent technology utilization is video detection. A camera feeds a small computer that can "see" if a vehicle is present.
Experimental setup: In order to implement the Intelligent Traffic Signal Simulator, one needs to setup and assemble the hardware components and write a program to control the intelligent traffic signal simulator.
The layout of the Intelligent Traffic Signal Simulator is displayed in Figure 1. The blocks, which are labeled N1, N2, N3, E1, E2, E3, S1 and W1 are the infrared object detectors.
Hardware components: The traffic light system consists of four important components: the controller which is the brain to the system, the sensors which detect the presence of vehicles, the light emitting diodes (LED) which act as the actuator and the countdown timers which is displayed in Lab VIEW.
BASIC STAMP 2 (BS2) is used as the microcontroller of the traffic signal. The BS2, which needs to be plugged to the Board of Education (BoE), is directly attached to the computer in order to program it. The wiring for the output and input signals is done from this board. Figure 2 shows the Board of Education to which a 9V DC power is supplied. There is also a DB9 connector, that is connected to the COM port of computer using RS-232 serial cable, for BS2 programming and serial communication during runtime. Next to the BS2, there is a breadboard. The breadboard has many strips of copper, which run underneath the board in a horizontal fashion. These strips connect the sockets to each other.
Performance analysis of shell and tube heat exchanger using miscible system
Performance analysis of shell and tube heat exchanger using miscible system
A heat exchanger is a device in which energy is transferred from one fluid to another across a solid surface. Exchanger analysis and design therefore involve both convection and conduction. Two important problems in heat exchanger analysis are (1) rating existing heat exchangers and (ii) sizing heat exchangers for a particular application. Rating involves determination of the rate of heat transfer, the change in temperature of the two fluids and the pressure drop across the heat exchanger. Sizing involves selection of a specific heat exchanger from those currently available or determining the dimensions for the design of a new heat exchanger, given the required rate of heat transfer and allowable pressure drop. The LMTD method can be readily used when the inlet and outlet temperatures of both the hot and cold fluids are known. When the outlet temperatures are not known, the LMTD can only be used in an iterative scheme. In this case the effectiveness-NTU method can be used to simplify the analysis. The choice of heat exchanger type directly affects the process performance and also influences plant size, plant layout, length of pipe runs and the strength and size of supporting structures. The most commonly used type of heat exchanger is the shell-and-tube heat exchanger, the optimal design of which is the main objective of this study. Computer software marketed by companies such as HTRI and HTFS are used extensively in the thermal design and rating of HEs. These packages incorporate various design options for the heat exchangers including the variations in the tube diameter, tube pitch, shell type, number of tube passes, baffle spacing, baffle cut, etc. A primary objective in the Heat Exchanger Design (HED) is the estimation of the minimum heat transfer area required for a given heat duty, as it governs the overall cost of the HE. But there is no concrete objective function that can be expressed explicitly as a function of the design variables and in fact many numbers of discrete combinations of the design variables are possible as is elaborated below. The tube diameter, tube length, shell types etc. are all standardized and are available only in certain sizes and geometry. And so the design of a shell-and-tube heat exchanger usually involves a trial and error procedure where for a certain combination of the design variables the heat transfer area is calculated and then another combination is tried to check if there is any possibility of reducing the heat transfer area. Since several discrete combinations of the design configurations are possible, the designer needs an efficient strategy to quickly locate the design configuration having the minimum heat exchanger cost. Thus the optimal design of heat exchanger can be posed as a large scale, discrete, combinatorial optimization problem (13). Most of the traditional optimization techniques based on gradient methods have the possibility of getting trapped at local optimum depending upon the degree of non-linearity and initial guess. Hence, these traditional optimization techniques do not ensure global optimum and also have limited applications. In the recent past, some experts studied on the design, performance analysis and simulation studies on heat exchangers(12),(13), (15), (16), (18). Modeling and Simulation of Shell and Tube Heat Exchangers Under Milk Fouling was carried out (15). Dynamic Model for Shell and Tube Heat Exchangers was discussed [12). Shell and Tube heat exchangers are applied where high temperature and pressure demands are significant and can be employed for a process requiring large quantities of fluid to be heated or cooled. Due to their design, these exchangers offer a large heat transfer area and provide high heat transfer efficiency in comparison with others. Modeling is a representation of physical or chemical process by a set of mathematical relationships that adequately describe the significant process behavior. Improving or understanding chemical process operation is a major objective for developing a process model. These models are often used for Process design, Safety system analysis and Process control. The simulation of an industrial system on a computer involves mathematical representation of the physical process undergone by the various components of the system, by a set of equations, which are in turn solved. Simulation is much cheaper than setting up big experiments or building prototypes of physical system and variables on the behavior of the system. A steady state model for the outlet temperature of both the cold and hot fluid of a shell and tube heat exchanger will be developed and simulated, which will be verified with the experiments conducted. Based on these observations correlations to find film heat transfer coefficients will be developed.
MATERIALS AND METHODS
Experimental Studies
Experimental Set up: Experiments were conducted on a 1-1 Shell and Tube Heat Exchanger. The Fig. 1 shows the schematic diagram of the heat exchanger
A heat exchanger is a device in which energy is transferred from one fluid to another across a solid surface. Exchanger analysis and design therefore involve both convection and conduction. Two important problems in heat exchanger analysis are (1) rating existing heat exchangers and (ii) sizing heat exchangers for a particular application. Rating involves determination of the rate of heat transfer, the change in temperature of the two fluids and the pressure drop across the heat exchanger. Sizing involves selection of a specific heat exchanger from those currently available or determining the dimensions for the design of a new heat exchanger, given the required rate of heat transfer and allowable pressure drop. The LMTD method can be readily used when the inlet and outlet temperatures of both the hot and cold fluids are known. When the outlet temperatures are not known, the LMTD can only be used in an iterative scheme. In this case the effectiveness-NTU method can be used to simplify the analysis. The choice of heat exchanger type directly affects the process performance and also influences plant size, plant layout, length of pipe runs and the strength and size of supporting structures. The most commonly used type of heat exchanger is the shell-and-tube heat exchanger, the optimal design of which is the main objective of this study. Computer software marketed by companies such as HTRI and HTFS are used extensively in the thermal design and rating of HEs. These packages incorporate various design options for the heat exchangers including the variations in the tube diameter, tube pitch, shell type, number of tube passes, baffle spacing, baffle cut, etc. A primary objective in the Heat Exchanger Design (HED) is the estimation of the minimum heat transfer area required for a given heat duty, as it governs the overall cost of the HE. But there is no concrete objective function that can be expressed explicitly as a function of the design variables and in fact many numbers of discrete combinations of the design variables are possible as is elaborated below. The tube diameter, tube length, shell types etc. are all standardized and are available only in certain sizes and geometry. And so the design of a shell-and-tube heat exchanger usually involves a trial and error procedure where for a certain combination of the design variables the heat transfer area is calculated and then another combination is tried to check if there is any possibility of reducing the heat transfer area. Since several discrete combinations of the design configurations are possible, the designer needs an efficient strategy to quickly locate the design configuration having the minimum heat exchanger cost. Thus the optimal design of heat exchanger can be posed as a large scale, discrete, combinatorial optimization problem (13). Most of the traditional optimization techniques based on gradient methods have the possibility of getting trapped at local optimum depending upon the degree of non-linearity and initial guess. Hence, these traditional optimization techniques do not ensure global optimum and also have limited applications. In the recent past, some experts studied on the design, performance analysis and simulation studies on heat exchangers(12),(13), (15), (16), (18). Modeling and Simulation of Shell and Tube Heat Exchangers Under Milk Fouling was carried out (15). Dynamic Model for Shell and Tube Heat Exchangers was discussed [12). Shell and Tube heat exchangers are applied where high temperature and pressure demands are significant and can be employed for a process requiring large quantities of fluid to be heated or cooled. Due to their design, these exchangers offer a large heat transfer area and provide high heat transfer efficiency in comparison with others. Modeling is a representation of physical or chemical process by a set of mathematical relationships that adequately describe the significant process behavior. Improving or understanding chemical process operation is a major objective for developing a process model. These models are often used for Process design, Safety system analysis and Process control. The simulation of an industrial system on a computer involves mathematical representation of the physical process undergone by the various components of the system, by a set of equations, which are in turn solved. Simulation is much cheaper than setting up big experiments or building prototypes of physical system and variables on the behavior of the system. A steady state model for the outlet temperature of both the cold and hot fluid of a shell and tube heat exchanger will be developed and simulated, which will be verified with the experiments conducted. Based on these observations correlations to find film heat transfer coefficients will be developed.
MATERIALS AND METHODS
Experimental Studies
Experimental Set up: Experiments were conducted on a 1-1 Shell and Tube Heat Exchanger. The Fig. 1 shows the schematic diagram of the heat exchanger
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