Environmental Simulation Models Research Articles

Prediction and analysis of PACS performance with the simulation tool MIRACLES.

Since the construction of image information systems appears to be extremely difficult in practice, BAZIS has decided to use computer modelling and simulation as decision support tools. In order to support the construction of simulation models, the simulation package and modelling environment MIRACLES (Medical Image Representation, Archiving and Communication Learned from Extensive Simulation) has been developed by BAZIS. This paper describes modelling and simulation techniques in general, as well as the benefits of simulation within the scope of designing Picture Archiving and Communication Systems (PACS). In order to illustrate the theory, results of a concrete yet simple PACS, which has been simulated with MIRACLES, will be described and discussed.

Simulation Modelling Using an Interactive Simulation Program Generator

The development of an interactive simulation program generator which is available on micro and mainframe computers is outlined. The generator forms part of a simulation environment being researched into and constructed by a group of researchers at the London School of Economics. The generated programs are written in Pascal, using a suite of routines which assume a three-phase structure for simulation programs. Experiences of modelling using such a simulation modelling environment are outlined, as well as details of related research and future research plans.

A multimedia assessment framework for emission control strategies

The types and rates of pollutant emissions from coal-fired power plants depend on plant design, coal characteristics, and environmental control policy. A multiobjective approach to decisionmaking on pollution control standards is discussed which includes the multimedia (air, land, water) effects of the standards. A mix of objective and subjective information is utilized and is obtained by linking an environmental simulation model with a method for eliciting a multipollutant dose-response curve and a subjective assessment of the “ willingness to pay” to avoid one more unit of various impacts. This study suggests that trade-offs between direct measures of impacts, such as human health effects and control costs, can be made for regulatory standard setting.

APPLICATION OF A HYDROLOGIC MODEL FOR LAND USE PLANNING IN FLORIDA1

ABSTRACT: An environmental simulation model of the Upper St. Johns River Basin, Florida, has been developed in order to predict hydrologic responses under proposed management plans. Land use projections for each of 19 hydrologic planning units are provided by a linear programming analysis of agricultural activities. Inputs to the model include rainfall, runoff, evapotranspiration (ET), aquifer properties, topography, soil types, and vegetative patterns. A water balance is developed in the uplands based on infiltration, ET, surface runoff, and groundwater flow. Valley continuity is based on stage‐volume relationship for inflows and outflows and a variable roughness coefficient dependent on vegetative patterns. Land use changes form the basis for predicting hydroperiod variation under alternative management schemes. Plans are ranked according to two criteria, deviation from a natural hydroperiod and flood or drought control provided. Results indicate that (1) a single reservoir without irrigation and (2) floodplain preservation plans are superior to (3) multiple reservoir with irrigation and (4) uncontrolled floodplain plans with regard to both criteria.

The development of a computer-aided building environment and services simulation model: Architectural Sci. Rev., Vol 15 (1972) No 4, pp 77–85

SUMMARY This paper describes the development of an interactive. computer-aided simulation model for the design and analysis of the service systems creating and maintaining the internal environment of a high-rise office building. The model is part of an overall programme of computer-aided architectural design being developed by the Department of Architectural Science at the University of Sydney, Australia. The model is seen as a practical design-analysis tool as well as a powerful research tool enabling a more thorough investigation of building services and. in particular, their interactions with other components of the building situation. The work described is concerned with the high-rise office building situation although the arguments and principles proposed could be extended to other building types. The first part of the paper presents relevant background matcrial to establish a context for the study. Current design methods for building services are reviewed and the application of computers to services...

Computer Simulation of Subway Environment

A designer-oriented computer program, designated the Single-Track Subway Environment Simulation model, has been developed to simulate multiple train operation in a single-train subway and to provide continuous peak, and average readings for the air velocity, temperature, and humidity throughout the stations, tunnels, and ventilation shafts. The program also provides continuous calculations of the location, velocity, and acceleration of the train(s) moving through the system. This program is intended for use in evaluating the influence of tunnel geometry, ventilation shaft design, and environmental control equipment upon airflow, temperature, and humidity in a subway. The aerodynamic portion of the program has been validated using data from a scale-model test facility.

Stable-Member Mounted Instrument Environment Simulation Model Development

The equations of motion for the stable member of a threegimbal platform are presented [3]. These equations are combined with models of the three platform control loops to formulate a model for the system. The system model is simplified and a digital simulation is developed for studying the motion of the stable member under conditions of dynamic vehicle angular environment.

Data selection for environmental simulations-A water temperature example

How should data be selected for use in costly environmental simulation models? For a particular problem, namely, thermal pollution, the question becomes, What combination of meteorologic conditions should be used to simulate the thermal stress on an estuary under natural or man-made heat loadings? Practical and standard approaches are required to select study conditions to support the preparation of expert testimony. A method combining computer simulations with series approximations is proposed. Three important parameters, wind speed, solar radiation, and dew point temperature, that influence the diurnal water temperature variation are considered in using the proposed analysis. Over 15 years of daily records of summer conditions at the weather station at Miami, Florida, are used to demonstrate the methodology. A Taylor series approximation is used to fit simulated responses in order to relate the probability of all days to the average day for the period studied. The technique should provide a tool for incorporating probability analysis into the study of thermal pollution in receiving waters. As a coarse approximation this approach can also be used for direct prediction of ambient water temperatures, very slight computer costs being invoked. The approach is adaptable to other environmental simulations.