Environment control strategies

Adaptive Control. An adaptive control strategy is one in which the controller characteristics, ie, the algorithm or the control parameters within it, are automatically adjusted for changes in the dynamic characteristics of the process itself (34). The incentives for an adaptive control strategy generally arise from two factors common in many process plants (/) the process and portions thereof are really nonlinear and (2) the process state, environment, and equipment s performance all vary over time. Because of these factors, the process gain and process time constants vary with process conditions, eg, flow rates and temperatures, and over time. Often such variations do not cause an unacceptable problem. In some instances, however, these variations do cause deterioration in control performance, and the controllers need to be retuned for the different conditions. 

The total cost for full-season weed control varies considerably with a specific crop or among different crops (21, 22). The production environment, especially the amount of available moisture influences the weed control strategy and the costs incurred. For example, in cotton the total cost for full-season weed control in West Texas was 76/ha, but in the Mississippi Delta the cost was 156/ha (20). 

UBA (2001). Chemicals in the Environment which I nterfere with the Endocrine Systems of Humans and Wildlife- Pollution, Effects, Control Strategies... 

Ktts, J. N., Jr., A. C. Lloyd, and J. L. Sprung. Chemical Reactions in Urban Atmosphere and Their Application to Air Pollution Control Strategies. Paper Presented at the International Symposium on Environment Measurements. Geneva, Oct. 2-4, 1973. 35 pp. 

The chemical characterization of atmospheric pollutants is of great importance for determining their primary sources, elucidating chemical reactions in the atmosphere, determining potential risk to the environment and developing a reasonable control strategy. 

Finlayson-Pitts, B. J., and J. N. Pitts, Jr., The Chemical Basis of Air Quality Kinetics and Mechanisms of Photochemical Air Pollution and Application to Control Strategies, Adv. Environ. Sci. Technol., 7, 76-162 (1977). 

Sistla, G N. Zhou, W. Hao, J.-Y. Ku, S. T. Rao, R. Bornstein, F. Freedman, and P. Thunis, Effects of Uncertainties in Meteorological Inputs on Urban Airshed Model Predictions and Ozone Control Strategies, Atmos. Environ., 30, 2011-2025 (1996). 

Winner, D. A., G. R. Cass, and R. A. Harley, Effect of Alternative Boundary Conditions on Predicted Ozone Control Strategy Performance A Case Study in the Los Angeles Area, Atmos. Environ., 29, 3451-3464 (1995). 

In facilities that handle or manufacture sensitive electronic devices, static control is a primary concern. The two important aspects of static control are control of static on personnel and control of static in the facility. Both these issues are part of a composite static control strategy. Static control in personnel starts with attention to the clothing and shoes worn by people working in the environment. Use of cotton clothing is essential, as cotton is neutral in the triboelectric series. Leather-soled shoes are preferred to shoes with composite or crepe soles. Shoe straps made of semiconductive material can be wrapped around a person s ankles and attached to... 

Wania, F. and D. MacKay (1996). Tracking the distribution of persistent organic pollutants. Control strategies for these contaminants will require a better understanding of how they move around the globe. Environ. Sci. Technol., 30 390A-396A. 

Many factors influence in complicated manners the magnitude and direction of transport and the distribution of chemicals in the environment. The factors include both the chemical properties and environmental variables such as emission, metrological and morphological conditions. Therefore, it is necessary to identify dominant factors to understand the fate and distribution of POPs in a system and to establish system-specific control strategies for POPs. 

Korea Ministry of Environment (KMOE), 2004a. Domestic status and control strategy of POPs products and waste (I). KMOE report (in Korean), Seoul, Korea. 

Accurate and precise identifications and measurements of specific chemical substances are fundamental to environmental studies and protection programs. Determinations are required to understand natural background concentrations of chemicals in the environment, the nature and extent of environmental pollution by anthropogenic chemicals, trends in concentrations of these substances, the transport and fate of chemical substances, and the causes of variations of concentrations intime and space. Accurate and precise determinations are also required to assess human health and ecological risks caused by exposure to natural and anthropogenic substances, establish air and water quality standards, develop pollution control strategies, evaluate the effectiveness of pollution prevention and treatment technologies, and monitor compliance with and the effectiveness... 

Sillman S. (1993) Tropospheric ozone the debate over control strategies. Ann. Rev. Energy Environ. 18, 31-56. 

---