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31.
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Comprehensive temperature monitoring in an in-vessel forced-aeration static-bed composting process 总被引:6,自引:0,他引:6
Masafumi Tateda Le Duc Trung Nguyen Viet Hung Michihiko Ike Masanori Fujita 《Journal of Material Cycles and Waste Management》2002,4(1):62-69
Comprehensive temperature monitoring was done in an in-vessel forced-aeration static-bed composting process using sewage sludge.
The three layers that divided the compost pile horizontally showed different temperature distributions. The temperature of
the top layer appeared not to be influenced by the ambient temperature. The temperature of the center area of the top layer
was taken to be the representative temperature for evaluating composting start-up performance. The temperature of the bottom
layer was strongly influenced by the ambient temperature, and the temperature of the center area of the bottom layer was taken
to be the representative temperature for pathogen control as it was the minimum temperature in the reactor. Composting start-up
performance was influenced by several factors when the ambient temperature was either below or above 20°C. When the ambient
temperature was below 20°C, the time taken to reach 65°C (T
65) was influenced by the temperature of inflowing air, but when the temperature was higher than 20°C, it was influenced by
the ratio of sewage sludge to seed compost (F/S). T
65 was least when F/S was 1–2.
Received: January 9, 2001 / Accepted: October 10, 2001 相似文献
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35.
集体林地使用权市场制度的建立与完善 总被引:6,自引:0,他引:6
集体林地使用权市场将是我国南方集体林区土地市场发展的主要内容,它的健康发展需要一套制度来保障.在介绍集体林地使用权市场类型的基础上,分析了我国集体林地使用权市场制度的建设状况,并提出了今后急待建立和完善的林地使用权市场制度的主要内容. 相似文献
36.
本文从中国环境立法,特别是再次修改《大气污染防治法》等展望中国大气污染防治的重要战略方向。 相似文献
37.
John Doherty John M. Johnston 《Journal of the American Water Resources Association》2003,39(2):251-265
ABSTRACT: The use of a fitted parameter watershed model to address water quantity and quality management issues requires that it be calibrated under a wide range of hydrologic conditions. However, rarely does model calibration result in a unique parameter set. Parameter nonuniqueness can lead to predictive nonuniqueness. The extent of model predictive uncertainty should be investigated if management decisions are to be based on model projections. Using models built for four neighboring watersheds in the Neuse River Basin of North Carolina, the application of the automated parameter optimization software PEST in conjunction with the Hydrologic Simulation Program Fortran (HSPF) is demonstrated. Parameter nonuniqueness is illustrated, and a method is presented for calculating many different sets of parameters, all of which acceptably calibrate a watershed model. A regularization methodology is discussed in which models for similar watersheds can be calibrated simultaneously. Using this method, parameter differences between watershed models can be minimized while maintaining fit between model outputs and field observations. In recognition of the fact that parameter nonuniqueness and predictive uncertainty are inherent to the modeling process, PEST's nonlinear predictive analysis functionality is then used to explore the extent of model predictive uncertainty. 相似文献
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Seppo Väyrynen Nina Nevala-Puranen Heli Kirvesoja 《International journal of occupational safety and ergonomics》2013,19(4):294-304
Footedness is a personal quality like handedness. Footedness may be associated with moving ability during mounting, dismounting, and jumping movements. Occupational accidents have occurred during movement at different working levels, during the use of access and exit systems, and during the mounting of vehicles. Aging can also affect accident risk and body laterality. For example, falling accidents on stairs are common among the elderly. One reason for accidents may be that the structure of the access system or stair system is unsuitable for individual moving patterns depending partly on body laterality. Footedness and the way the feet are used may be contradictory to the demands of the moving situation, especially during uncommon or rapid situations. This contradiction may trigger disturbance during moving. The aims of this pilot study were (a) to review the literature briefly and (b) to describe the use of the dominant and nondominant foot by farmers and the elderly when mounting a tractor and stairs, respectively. The study also gives ideas for future studies based on both (a) and (b). 相似文献
40.
Stefan Kornecki Adam Siemieński 《International journal of occupational safety and ergonomics》2013,19(1):75-83
The aim of the work is to outline a procedure of finding force-velocity (F–V) characteristics (F = f(V)) of individual skeletal muscles of the human locomotor system. The presentation is based on an example concerning extensors of the elbow joint: the lateral and long heads of triceps brachii (TBCIat and TBCIong). The experimental part of the procedure involves a natural movement of using the upper extremity to push an external object of variable, adjustable load, engaging both the elbow and shoulder joint.Five men aged 23 took part in the experiment. Their task was to push the handle of a physical pendulum whose moment of inertia could be adjusted within the range of 58 kg m2-450 kg m2, so as to give it maximum angular velocity. During each trial the movement of the trunk, of the upper extremity and of the pendulum was video recorded and the force applied with the hand to the handle of the pendulum was measured.In order to find the F–V characteristics a simulation model SHOULDER was used, which is capable of solving the synergy problem for muscles of the arm and the shoulder girdle.It was found that despite considerable dispersion of experimental points the respective regression lines revealed a clear tendency of decreasing muscle force for increased shortening velocity of the monoarticular head (TBCIat) and of increasing muscle force for increased lengthening velocity of the biarticular head (TBCIong) of the triceps brachii muscle. 相似文献