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331.
特种设备数据服务平台是基于B/S结构开发的信息管理系统,能面向客户并实现监察机构、检验机构、使用机构三方数据联动,把客户特种设备管理、收费系统、网上报检、历年检验报告查询、检验进度查询、委托业务管理、用户点对点资料传输等实现一站式服务。项目的应用为监察机构、检验机构和企业实现数据资源高效管理,简化业务办理流程,加强企业对特种设备管理的力度提供技术支持。  相似文献   
332.
末梢水与其水源水的数据“倒挂”现象是影响居民饮水健康的安全隐患。基于末梢水数据“倒挂”现象在新闻报道、政府信息公开及相关调查研究中的表现形式,分析了引起末梢水数据“倒挂”的原因主要包括:监测采样、分析偏差,物理因素和化学、生物反应以及综合因素造成的污染等。提出,在饮用水水源方面,加强规范化管理,保持水源水水质合格并长期稳定;在水处理阶段,选择适宜且安全高效的水处理方式;在水管输送阶段,选择健康的管道材质并合理规划设计、维护输水管网体系;在饮用水使用阶段,加强用水宣传,让居民养成良好的健康用水习惯。从而逐渐消除末梢水数据“倒挂”现象,保障居民的饮水安全。  相似文献   
333.
通过氰根在线监测仪在紫金山金矿废水排放系统中的应用实例,对在线监测仪使用过程中所遇到的常见问题进行分析,总结了使用在线监测仪的日常维护内容及常见故障的处理经验.  相似文献   
334.
Correctly quantifying the impacts of rare apex marine predators is essential to ecosystem-based approaches to fisheries management, where harvesting must be sustainable for targeted species and their dependent predators. This requires modelling the uncertainty in such processes as predator life history, seasonal abundance and movement, size-based predation, energetic requirements, and prey vulnerability. We combined these uncertainties to evaluate the predatory impact of transient leopard seals on a community of mesopredators (seals and penguins) and their prey at South Georgia, and assess the implications for an ecosystem-based management. The mesopredators are highly dependent on Antarctic krill and icefish, which are targeted by regional fisheries. We used a state-space formulation to combine (1) a mark-recapture open-population model and individual identification data to assess seasonally variable leopard seal arrival and departure dates, numbers, and residency times; (2) a size-based bioenergetic model; and (3) a size-based prey choice model from a diet analysis. Our models indicated that prey choice and consumption reflected seasonal changes in leopard seal population size and structure, size-selective predation and prey vulnerability. A population of 104 (90–125) leopard seals, of which 64% were juveniles, consumed less than 2% of the Antarctic fur seal pup production of the area (50% of total ingested energy, IE), but ca. 12–16% of the local gentoo penguin population (20% IE). Antarctic krill (28% IE) were the only observed food of leopard seal pups and supplemented the diet of older individuals. Direct impacts on krill and fish were negligible, but the “escapement” due to leopard seal predation on fur seal pups and penguins could be significant for the mackerel icefish fishery at South Georgia. These results suggest that: (1) rare apex predators like leopard seals may control, and may depend on, populations of mesopredators dependent on prey species targeted by fisheries; and (2) predatory impacts and community control may vary throughout the predator's geographic range, and differ across ecosystems and management areas, depending on the seasonal abundance of the prey and the predator's dispersal movements. This understanding is important to integrate the predator needs as natural mortality of its prey in models to set prey catch limits for fisheries. Reliable estimates of the variability of these needs are essential for a precautionary interpretation in the context of an ecosystem-based management.  相似文献   
335.
The importance of cost planning for solid waste management (SWM) in industrialising regions (IR) is not well recognised. The approaches used to estimate costs of SWM can broadly be classified into three categories - the unit cost method, benchmarking techniques and developing cost models using sub-approaches such as cost and production function analysis. These methods have been developed into computer programmes with varying functionality and utility. IR mostly use the unit cost and benchmarking approach to estimate their SWM costs. The models for cost estimation, on the other hand, are used at times in industrialised countries, but not in IR. Taken together, these approaches could be viewed as precedents that can be modified appropriately to suit waste management systems in IR. The main challenges (or problems) one might face while attempting to do so are a lack of cost data, and a lack of quality for what data do exist. There are practical benefits to planners in IR where solid waste problems are critical and budgets are limited.  相似文献   
336.
简扼介绍了关系型数据库Superbase,并以一个环境监测实例阐述如何运用Superbase,无须编程而建立图形界面的过程。  相似文献   
337.
338.
This study examines negative and positive infant handling behavior in 24 free-ranging yellow baboon infants (Papio cynocephalus) studied over a 5-year period in Mikumi National Park, Tanzania. We test predictions of the female reproductive competition hypothesis to explain patterns of infant handling behavior by adult females (excluding the infants mother) in relation to observed cases of infant mortality by age 3 months (25% of infants in this study). Results show that: (1) low-ranking infants received more negative infant handling than high-ranking infants; conversely high-ranking infants received more positive infant handling; (2) female kin engaged in higher levels of positive infant handling than did non-kin, whereas non-kin showed higher levels of negative infant handling; (3) rates of negative infant handling varied by season, with high levels at the onset of the rainy season; and (4) high level of negative infant handling was a significant predictor of infant mortality by age 3 months (infant rank and sex did not predict survival). We discuss how the occurrence and interpretation of infant handling behavior in the literature has likely been confused by different definitions of this behavior, as well as differences in the socio-ecological context in which this behavior occurs.Communicated by C. Nunn  相似文献   
339.
测定回弹法专用测强曲线的数据融合方法   总被引:5,自引:0,他引:5  
混凝土强度现场检测结果的准确性直接关系到结构的安全性。笔者利用通用回弹测强曲线提供的共性信息和现场试验得到的个性信息 ,通过数据融合方法 ,提出适应于现场情况的混凝土强度与回弹值之间的关系曲线。该曲线仍运用原有的幂函数形式并保持回归参数不变 ,通过增加位置参数反映现场试验的个性信息。其修正后的结果既反映混凝土回弹值和强度值之间的一般关系 ,又反映现场试验的实际情况。在混凝土回弹检测中采用该曲线 ,可极大地提高检测精度和检测结果的可靠性  相似文献   
340.
Jeremy Shoham 《Disasters》1987,11(4):282-285
A major area of investment in data collection in developing countries has been that of nutritional surveillance and monitoring. From recent debate it is clear that there is currently no consensus on the potential role of nutritional status as an early warning indicator. The author presents a synthesis of the broad spectrum of views on the role nutritional surveillance could or should have in early warning. Conceptual problems and technical difficulties are reviewed in the light of recent experiences in Africa and Asia. The author raises a number of issues for future discussion in this ongoing debate.  相似文献   
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