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The design of single-point, subsurface moorings is carried out a present by a design engineer with the help of some computer programs. These computer programs are used for analyzing the mooring, but the setting-up of the initial mooring configuration and the subsequent modifications on the basis of the results of the analysis are carried out by the design engineer.An expert system for mooring design is developed to eliminate the human expert from the design process and thus to enable a novice to design a mooring by himself. Using the expert system, an optimum least-weight in air design can be developed in much less time than is usually required in conventional procedures. Perhaps the most significant advantage is that the system can serve as a vehicle for effective transfer of present day expertise for future applications.The system is developed and implemented on an IBM PC/AT. It has a user-friendly, interactive, menu-driven input procedure and a sophisticated output facility. The design process is totally automated and the requirement to consult a human expert is easily eliminated. The system has tremendous flexibility and a knowledge engineer can easily adapt it to the specific requirements of a particular user. The concept of machine learning is introduced by recording the failure data and using this information in the later decision-making processes. A CAD package, AUTOCAD, is used to generate the drawings and an interface is developed between the CAD package and the expert system so that the former is transparent to the user.  相似文献   
2.
The selection of landfill sites for municipal solid waste (MSW) disposal involves consideration of geological, hydrological and environmental parameters which exhibit large spatial variability. Therefore, it is necessary to define, to what extent the chosen sites are reliable such that the probability of environmental pollution and health risks to population is minimal. In the present study, groundwater vulnerability to contamination has been assessed using the standard DRASTIC method. The results showed that the study region has 9.45% of very less, 32.94% of less, 25.47% of moderate, 22.79% of high and 9.35% of very high vulnerable zones. The study also revealed that none of the landfills are located in safe zones. This suggests that it requires proper remedial measures to avoid environmental pollution. A landfill site selection process has been carried out using the Analytical Hierarchy Process integrated with Geographical Information System tools. The obtained results showed that only 3.59?km2 (0.08%) of the total area is suitable for landfills. The reliability analysis of the site suitability revealed that landfills are located at unreliable locations where the probability of risk to environmental pollution is high. The presented approach assists decision-makers in selecting reliable locations for the safe disposal of MSW.  相似文献   
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Precision agriculture often relies on high-resolution imagery to delineate the variability within a field. Airborne Environmental Research Observational Camera (AEROCam) was designed to meet the needs of agriculture producers, ranchers, and researchers, who require high-resolution imagery in a near real-time environment for rapid decision support. AEROCam was developed and operated through a unique collaboration between several departments at the University of North Dakota, including the Upper Midwest Aerospace Consortium (UMAC), the School of Engineering and Mines, and flight operations at the John D. Odegard School of Aerospace Sciences. AEROCam consists of a Redlake MS4100 area-scan multi-spectral digital camera that features a 1920 × 1080 CCD array (7.4-μm detector) with 8-bit quantization. When operated at ~2 km above ground level, multispectral images with four bands in the visible and near infrared have a ground sample distance of 1 m with a horizontal extent of just over 1.6 km. Depending on the applications, flying at different altitudes can adjust the spatial resolution from 0.25 to 2 m. Rigorous spectral and radiometric calibrations allow AEROCam to be used in a variety of applications, qualitative and quantitative. Equipped with an inertial measurement unit (IMU) system, the images acquired can be geo-referenced automatically and delivered to end users near real time through our Digital Northern Great Plains system (DNGP). The images are also available to zone mapping application for precision farming (ZoneMAP), an online decision support tool for creating management zones from remote sensing imagery and data from other sources. Operational since 2004, AEROCam has flown over 250 sorties and delivered over 150,000 images to the users in the Northern Great Plains region, resulting in numerous applications in precision agriculture and resource management.  相似文献   
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Satellite imagery has proven potential in farm level applications, especially in the US Upper Midwest where the farm sizes are large enough to be studied using high and medium resolutions. In order for farmers to use this technology to improve their productivity and income, it is imperative that they be sufficiently exposed to the technology so that they are able to take full advantage of it. Training of farmers and ranchers in satellite imagery use started at the University of North Dakota in 2000 and has been refined over time. The basic ‘hands on’ training involves downloading imagery from the Upper Midwest Aerospace Consortium (UMAC) website, downloading and use of free visualization software programs available on the web and an introduction to the various application possibilities. Advanced training, which involves more complex extraction of useful information from digital images, is also available to those who complete the basic training. Over 500 farmers, ranchers, crop consultants and other end users have been trained through this programme and the results are beginning to show through the success stories of cost savings and environmental benefits that have emerged.  相似文献   
5.
The increasing demand for building materials has led to indiscriminate exploitation of clay-rich topsoil from wetlands including the paddy lands of Central Kerala in the southwestern coast of India. The problem is critical in areas adjoining the major developmental centers having low per capita land and natural resource availability. Loss of fertile topsoil, shrinkage of agricultural lands and consequent food security issues, erosion of naturally evolved nutrients, lowering of water table in wells adjacent to the mining sites, etc., are some of the major environmental issues arising from indiscriminate brick and tile clay mining. Although, brick and tile clay mining brings short-term economic benefits and employment opportunities to a section of people, the process in the long run creates severe damages to the environmental settings of the area. The present paper deals with a few aspects of brick and tile clay mining in the paddy lands of Central Kerala, especially around Kochi City, a fast developing urban-cum-industrial center in South India, which demands large quantities of building materials including bricks and tiles for construction of infrastructural facilities. It is estimated that 729,695 tons/year (ty?1) of brick and tile clays are extracted from the coastal lowlands of Central Kerala, spreading to the Chalakudy (135,975 ty?1), Periyar (483,820 ty?1) and Muvattupuzha (109,900 ty?1) river basins. The N, P and K loss through extraction of brick and tile clays amounts to 210 ty?1, 96 ty?1 and 9,352 ty?1, respectively. As nutrient loss is an irreversible process in human time scale, its implications on agricultural productivity is a matter of serious concern. The study warrants the need for a comprehensive policy with an aim to regulate the mining activities on an environment- friendly basis in the densely populated coasts of the world, in general, and the study area in particular.  相似文献   
6.
A red rain phenomenon occurred in Kerala, India starting from 25th July 2001, in which the rainwater appeared coloured in various localized places that are spread over a few hundred kilometers in Kerala. Maximum cases were reported during the first 10 days and isolated cases were found to occur for about 2 months. The striking red colouration of the rainwater was found to be due to the suspension of microscopic red particles having the appearance of biological cells. These particles have no similarity with usual desert dust. An estimated minimum quantity of 50,000 kg of red particles has fallen from the sky through red rain. An analysis of this strange phenomenon further shows that the conventional atmospheric transport processes like dust storms etc. cannot explain this phenomenon. The electron microscopic study of the red particles shows fine cell structure indicating their biological cell like nature. EDAX analysis shows that the major elements present in these cell like particles are carbon and oxygen. Strangely, a test for DNA using Ethidium Bromide dye fluorescence technique indicates absence of DNA in these cells. In the context of a suspected link between a meteor airburst event and the red rain, the possibility for the extraterrestrial origin of these particles from cometary fragments is discussed.  相似文献   
7.
It is a well established fact that geomorphology of an area exercises a significant control on the groundwater occurrence and movement. In an operational remote sensing project carried out by the National Remote Sensing Agency, India, this relationship between geomorphology and groundwater, coupled with the ability of Landsat data to provide regional geomorphic information, has been utilised to arrive at broad groundwater potential zones.  相似文献   
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