International Journal of Heat and Mass Transfer, 2004
Average Nusselt number information was collected for all textbook-standard, non-circular cylinder... more Average Nusselt number information was collected for all textbook-standard, non-circular cylinders in cross-flow in air. These non-circular cross-sections include: squares, diamonds, flat plates perpendicular to the freestream, ellipses, hexagons, rectangles, and circles. This collection encompassed both venerable data which form the basis of the correlations recommended by current textbooks and all of the modern data that could be found in the literature. For each of the selected non-circular cross-sections, the available data were displayed, evaluated, and compared with those for all related cross-sections. On the basis of the merits of the information collected for each cross-sectional shape, correlations are recommended which are intended to form a new set of textbook standards. Also, the new correlations avoid errors made in the current textbook correlations which are caused by an inconsistency in the selection of the characteristic dimension relative to that used by the original investigators. Almost exclusively, the new correlations are based on modern experimental data. In order to provide a complete compendium of cross-flow heat transfer information, correlations for the circular cylinder and the sphere have been included in the table. The correlation for the circular cylinder is original to this paper.
International Journal of Heat and Mass Transfer, 2005
A method has been developed for determining the streamwise variation of the temperature of a movi... more A method has been developed for determining the streamwise variation of the temperature of a moving sheet in the 13 presence of a co-flowing fluid. The solution does not depend on any material property of the sheet, its velocity, or its 14 thickness. The solution is also independent of the properties of the fluid aside from the Prandtl number. Furthermore, 15 the actual velocities of the sheet and the fluid need not be specified, but only their ratio is required. In the development 16 of the method, a large knowledge base was first created by solving the differential equations for mass, momentum, and 17 energy. The tabulated knowledge base served as input to a purely algebraic procedure whose end result is the stream-18 wise variation of the sheet temperature. The procedure is iterative but requires no more than a least-squares curve-fit-19 ting capability. The iterative procedure is robust in that the converged result is independent of the initial iterant. It is 20 also self correcting in the presence of an inadvertent error. Another method for determining the streamwise temperature 21 variation, the relative-velocity model, was also investigated, and its accuracy assessed. 22 Ó
The pharmaceutical industry has produced many drugs that have benefited man. Political frameworks... more The pharmaceutical industry has produced many drugs that have benefited man. Political frameworks designed to govern the industry must maintain these benefits. However, regulation needs to be sufficiently robust to protect public health from drugs that are unsafe, ineffective, or unnecessary. The extent of industry influence over drug regulation, at the expense of other interested parties, suggests that the current system could be more robust. The many ways in which the pharmaceutical industry can influence governments and regulatory agencies are discussed, and methods by which this influence can be curbed are suggested.
Transportation Research Part D-transport and Environment, 2002
To address some of the uncertainties inherent in large-scale models, two very different urban mod... more To address some of the uncertainties inherent in large-scale models, two very different urban models, an advanced travel demand model and an integrated land use and transportation model, are applied to evaluate land use, transit, and auto pricing policies in the Sacramento, CA (US), region. The empirical and modeling literature is reviewed to identify effective land use, transit, and pricing policies and optimal combinations of those policies and to provide a comparative context for the results of the simulation. The study illustrates several advantages of this approach for addressing uncertainty in large-scale models. First, as Alonso [Predicting the best with imperfect data, AIP Journal (1968)] asserts, the intersection of two uncertain models produces more robust results than one grand model. Second, the process of operationalizing policy sets exemplifies the theoretical and structural differences in the models. Third, a comparison of the results from multiple models illustrates the implications of the respective models' strengths and weaknesses and may provide some insights into heuristic policy strategies. Some of the key findings in this study are (1) land use and transit policies may reduce vehicle miles traveled (VMT) and emissions by about 5-7%, and the addition of modest auto pricing policies may increase the reduction by about 4-6% compared to a future Base Case scenario for a 20-year time horizon; (2) development taxes and land subsidy policies may not be sufficient to generate effective transit-oriented land uses without strict growth controls elsewhere in the region; and (3) parking pricing should not be imposed in areas served by light rail lines and in areas in which increased densities are promoted with land subsidy policies. Ó
This paper presents a status report concerning on-going research and development work by a team o... more This paper presents a status report concerning on-going research and development work by a team of Canadian researchers to develop a microsimulation, agent-based, integrated model of urban land use and transportation. It describes in some detail the overall design and current status of the ILUTE (Integrated Land Use, Transportation, Environment) modelling system under development. The overall purpose of ILUTE is to simulate the evolution of an entire urban region over an extended period of time. Such a model is intended to replace conventional, aggregate, static models for the analysis of a broad range of transportation, housing and other urban policies. Agents being simulated in the model include individuals, households and establishments. The model operates on a ''100% sample'' (i.e., the entire population) of agents which, in the base case, are synthesized from more aggregate data such as census tables and which are then evolved over time by the model. A range of modelling methods are employed within the modelling system to represent individual agents' behaviours, including simple state transition models, random utility choice models, rule-based ''computational process'' models, and hybrids of these approaches. A major emphasis within ILUTE is the development of microsimulation models of market demandsupply interactions, particularly within the residential and commercial real estate markets. In addition, travel demand is modelled explicitly as the outcome of a combination of household and individual decisions concerning the participation in out-of-home activities over the course of a day. Spatial entities in the model include buildings, residential dwelling units and commercial floorspace, as well as aggregate ''spatial containers'' such as traffic zones, census tracts or grid cells.
Three land use and transport interaction models were applied to the Sacramento, CA region by vari... more Three land use and transport interaction models were applied to the Sacramento, CA region by various teams of researchers, and compared with each other and with the traditional transport demand model used by the regional government. This paper compares the results of the modeling efforts, focusing on how the design of the modeling frameworks and their application influenced the modeling results. A trend scenario was compared to three different policy scenarios, one involving HOV lane construction, one adding beltway construction as well as HOV construction, and a third involving light rail construction and limited pricing of automobile use. The results show how price and floorspace information is important, aggregate models are limited, equilibrium models are limited and calibration is important. Uncertainty in land use transport interaction models seems inevitable, and further research should investigate on how to best use such modeling frameworks to understand the influence of policy in the face of uncertain futures.
Sylhet city is third important city in Bangladesh after Dhaka and Chittagong. The population relo... more Sylhet city is third important city in Bangladesh after Dhaka and Chittagong. The population relocation rate is high in this district, enormous land cost and insufficiency of land, multipurpose now a day's high rise building is increased at significant in sylhet city. Previous record state that this region is affected by large ranges of earthquake at regular interval. For that Sylhet city is vulnerable to destructive earthquakes. The objective of this study is to analysis of drift or displacement of highrise building. Lateral loads are mainly responsible for drift. After completion it is found that seismic load is more critical than wind load, for this basis here seismic load is considered as well as wind load. The Structural Engineer have a challenge to control the drift within allowable range due to lateral loads for stability of structure. Three types of rigid frame high rise structures such as R.C.C beam slab building, R.C.C flat slab building and R.C.C beam slab with shear wall building was considered for analysis of drift. Three approximate formula for manual calculation of drift with respect to stiffness of beam and column are used. The study confirmed that the stiffness of column was more than stiffness of beam in all cases. It can be concluded that the stiffness of shear wall was more than stiffness of column. The highest lateral drifts were within the allowable limits. The computer programming for frame structure (beam slab building) was developed and found the deviation from hand calculation was 2.02% (maximum).The outcome of the study is a feasible process for the calculation of drift of high rise building.
International Journal of Heat and Mass Transfer, 2004
Average Nusselt number information was collected for all textbook-standard, non-circular cylinder... more Average Nusselt number information was collected for all textbook-standard, non-circular cylinders in cross-flow in air. These non-circular cross-sections include: squares, diamonds, flat plates perpendicular to the freestream, ellipses, hexagons, rectangles, and circles. This collection encompassed both venerable data which form the basis of the correlations recommended by current textbooks and all of the modern data that could be found in the literature. For each of the selected non-circular cross-sections, the available data were displayed, evaluated, and compared with those for all related cross-sections. On the basis of the merits of the information collected for each cross-sectional shape, correlations are recommended which are intended to form a new set of textbook standards. Also, the new correlations avoid errors made in the current textbook correlations which are caused by an inconsistency in the selection of the characteristic dimension relative to that used by the original investigators. Almost exclusively, the new correlations are based on modern experimental data. In order to provide a complete compendium of cross-flow heat transfer information, correlations for the circular cylinder and the sphere have been included in the table. The correlation for the circular cylinder is original to this paper.
International Journal of Heat and Mass Transfer, 2005
A method has been developed for determining the streamwise variation of the temperature of a movi... more A method has been developed for determining the streamwise variation of the temperature of a moving sheet in the 13 presence of a co-flowing fluid. The solution does not depend on any material property of the sheet, its velocity, or its 14 thickness. The solution is also independent of the properties of the fluid aside from the Prandtl number. Furthermore, 15 the actual velocities of the sheet and the fluid need not be specified, but only their ratio is required. In the development 16 of the method, a large knowledge base was first created by solving the differential equations for mass, momentum, and 17 energy. The tabulated knowledge base served as input to a purely algebraic procedure whose end result is the stream-18 wise variation of the sheet temperature. The procedure is iterative but requires no more than a least-squares curve-fit-19 ting capability. The iterative procedure is robust in that the converged result is independent of the initial iterant. It is 20 also self correcting in the presence of an inadvertent error. Another method for determining the streamwise temperature 21 variation, the relative-velocity model, was also investigated, and its accuracy assessed. 22 Ó
The pharmaceutical industry has produced many drugs that have benefited man. Political frameworks... more The pharmaceutical industry has produced many drugs that have benefited man. Political frameworks designed to govern the industry must maintain these benefits. However, regulation needs to be sufficiently robust to protect public health from drugs that are unsafe, ineffective, or unnecessary. The extent of industry influence over drug regulation, at the expense of other interested parties, suggests that the current system could be more robust. The many ways in which the pharmaceutical industry can influence governments and regulatory agencies are discussed, and methods by which this influence can be curbed are suggested.
Transportation Research Part D-transport and Environment, 2002
To address some of the uncertainties inherent in large-scale models, two very different urban mod... more To address some of the uncertainties inherent in large-scale models, two very different urban models, an advanced travel demand model and an integrated land use and transportation model, are applied to evaluate land use, transit, and auto pricing policies in the Sacramento, CA (US), region. The empirical and modeling literature is reviewed to identify effective land use, transit, and pricing policies and optimal combinations of those policies and to provide a comparative context for the results of the simulation. The study illustrates several advantages of this approach for addressing uncertainty in large-scale models. First, as Alonso [Predicting the best with imperfect data, AIP Journal (1968)] asserts, the intersection of two uncertain models produces more robust results than one grand model. Second, the process of operationalizing policy sets exemplifies the theoretical and structural differences in the models. Third, a comparison of the results from multiple models illustrates the implications of the respective models' strengths and weaknesses and may provide some insights into heuristic policy strategies. Some of the key findings in this study are (1) land use and transit policies may reduce vehicle miles traveled (VMT) and emissions by about 5-7%, and the addition of modest auto pricing policies may increase the reduction by about 4-6% compared to a future Base Case scenario for a 20-year time horizon; (2) development taxes and land subsidy policies may not be sufficient to generate effective transit-oriented land uses without strict growth controls elsewhere in the region; and (3) parking pricing should not be imposed in areas served by light rail lines and in areas in which increased densities are promoted with land subsidy policies. Ó
This paper presents a status report concerning on-going research and development work by a team o... more This paper presents a status report concerning on-going research and development work by a team of Canadian researchers to develop a microsimulation, agent-based, integrated model of urban land use and transportation. It describes in some detail the overall design and current status of the ILUTE (Integrated Land Use, Transportation, Environment) modelling system under development. The overall purpose of ILUTE is to simulate the evolution of an entire urban region over an extended period of time. Such a model is intended to replace conventional, aggregate, static models for the analysis of a broad range of transportation, housing and other urban policies. Agents being simulated in the model include individuals, households and establishments. The model operates on a ''100% sample'' (i.e., the entire population) of agents which, in the base case, are synthesized from more aggregate data such as census tables and which are then evolved over time by the model. A range of modelling methods are employed within the modelling system to represent individual agents' behaviours, including simple state transition models, random utility choice models, rule-based ''computational process'' models, and hybrids of these approaches. A major emphasis within ILUTE is the development of microsimulation models of market demandsupply interactions, particularly within the residential and commercial real estate markets. In addition, travel demand is modelled explicitly as the outcome of a combination of household and individual decisions concerning the participation in out-of-home activities over the course of a day. Spatial entities in the model include buildings, residential dwelling units and commercial floorspace, as well as aggregate ''spatial containers'' such as traffic zones, census tracts or grid cells.
Three land use and transport interaction models were applied to the Sacramento, CA region by vari... more Three land use and transport interaction models were applied to the Sacramento, CA region by various teams of researchers, and compared with each other and with the traditional transport demand model used by the regional government. This paper compares the results of the modeling efforts, focusing on how the design of the modeling frameworks and their application influenced the modeling results. A trend scenario was compared to three different policy scenarios, one involving HOV lane construction, one adding beltway construction as well as HOV construction, and a third involving light rail construction and limited pricing of automobile use. The results show how price and floorspace information is important, aggregate models are limited, equilibrium models are limited and calibration is important. Uncertainty in land use transport interaction models seems inevitable, and further research should investigate on how to best use such modeling frameworks to understand the influence of policy in the face of uncertain futures.
Sylhet city is third important city in Bangladesh after Dhaka and Chittagong. The population relo... more Sylhet city is third important city in Bangladesh after Dhaka and Chittagong. The population relocation rate is high in this district, enormous land cost and insufficiency of land, multipurpose now a day's high rise building is increased at significant in sylhet city. Previous record state that this region is affected by large ranges of earthquake at regular interval. For that Sylhet city is vulnerable to destructive earthquakes. The objective of this study is to analysis of drift or displacement of highrise building. Lateral loads are mainly responsible for drift. After completion it is found that seismic load is more critical than wind load, for this basis here seismic load is considered as well as wind load. The Structural Engineer have a challenge to control the drift within allowable range due to lateral loads for stability of structure. Three types of rigid frame high rise structures such as R.C.C beam slab building, R.C.C flat slab building and R.C.C beam slab with shear wall building was considered for analysis of drift. Three approximate formula for manual calculation of drift with respect to stiffness of beam and column are used. The study confirmed that the stiffness of column was more than stiffness of beam in all cases. It can be concluded that the stiffness of shear wall was more than stiffness of column. The highest lateral drifts were within the allowable limits. The computer programming for frame structure (beam slab building) was developed and found the deviation from hand calculation was 2.02% (maximum).The outcome of the study is a feasible process for the calculation of drift of high rise building.
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