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941.
青龙满族自治县被列为河北省桃林口水库上游重点治理区,境内大量“四荒”资源闲置浪费。该县立足县情,制定优惠政策,强化管理,因地制宜地开发这些资源,取得显著成效,其做法值得推广和借鉴。 相似文献
942.
The pattern of innovation in the global minerals industry is changing as the industry becomes increasingly globalised. In this paper, we look at the structure of innovation in the industry and the drivers of change. We first consider the broad international trends and then examine these more closely with special reference to the Australian industry. Issues addressed include the apparent decline in corporate research and development spending, changing patterns in research collaboration and outsourcing, and the uptake of information and communication technologies in the industry. We also look at the potential implications of these trends for step-change technological developments and at the role of technological innovation in the future development of the industry. 相似文献
943.
Puneet Srivastava James N. McNair Thomas E. Johnson 《Journal of the American Water Resources Association》2006,42(3):545-563
ABSTRACT: The performance of the Soil and Water Assessment Tool (SWAT) and artificial neural network (ANN) models in simulating hydrologic response was assessed in an agricultural watershed in southeastern Pennsylvania. All of the performance evaluation measures including Nash‐Sutcliffe coefficient of efficiency (E) and coefficient of determination (R2) suggest that the ANN monthly predictions were closer to the observed flows than the monthly predictions from the SWAT model. More specifically, monthly streamflow E and R2 were 0.54 and 0.57, respectively, for the SWAT model calibration period, and 0.71 and 0.75, respectively, for the ANN model training period. For the validation period, these values were ?0.17 and 0.34 for the SWAT and 0.43 and 0.45 for the ANN model. SWAT model performance was affected by snowmelt events during winter months and by the model's inability to adequately simulate base flows. Even though this and other studies using ANN models suggest that these models provide a viable alternative approach for hydrologic and water quality modeling, ANN models in their current form are not spatially distributed watershed modeling systems. However, considering the promising performance of the simple ANN model, this study suggests that the ANN approach warrants further development to explicitly address the spatial distribution of hydrologic/water quality processes within watersheds. 相似文献
944.
945.
Interannual Changes in the C:N:P Ratios of Seston and Zooplankton of a High Mountain Lake in Sierra Nevada,Spain 总被引:1,自引:0,他引:1
Villar-Argaiz M. Medina-Sánchez J. M. Carrillo P. 《Water, Air, & Soil Pollution: Focus》2002,2(2):359-378
We investigated the carbon, nitrogen and phosphorus content inthe seston and the zooplankton of a high-mountain lake duringthree years of contrasting physical and chemical conditions.Carbon in seston was ten times higher in 1995 than in 1996 and1997. Phosphorus content in seston was variable for the studyperiod, increasing gradually towards late summer in 1995, butpeaking abruptly in 1996 and 1997, reflecting atmosphericdepositions. Seston C:P were high and did not fit any definitepattern in 1995, and were particularly low after the thaw, increasing towards mid-summer in 1996 and 1997. As the seasonprogressed, major decreases in these ratios occurred coincidingwith important atmospheric inputs in the lake area. ZooplanktonN:P and C:P were negatively associated to the appearance ofrotifers and copepod nauplii in 1995, but positively correlatedto the ontogenetic development of the most abundant species,Mixodiaptomus laciniatus, in 1996. Seasonal variations inzooplankton N:P and C:P ratios showed limited interannual, butlarge intraannual variability. The comparison between the bulkcarbon in seston and zooplankton demands for this elementindicated that zooplankton were above food-quantity thresholdsfor maximum growth in 1995, 1996 and mid-season of 1997,therefore suffering only from food-quantity constraints afterthe thaw (nauplii dominance) and towards late season (adultdominance) in the latter year. The high C:P ratios in sestonrelative to zooplankton in 1995 imply that the zooplankton mayhave faced severe food-quality constraints (in terms ofphosphorus) during this year. Differences between bulkzooplankton and seston elemental nutrients are also discussed inrelation to the competitive abilities of species, andparticularly of Daphnia. 相似文献
946.
通过对四川省科技人力资源的潜力、结构变化的分析,提出建立统一规范的科技人才培养经费投入政策,加强科技人才资源的再开发,不拘一格引进科技人才,建立四川省科技人力资源监测系统等对策。 相似文献
947.
临夏回族自治州旅游客源市场分析与定位 总被引:2,自引:0,他引:2
本文在临夏州客源市场调查与分析的基础上,确定其客源市场应定位在周边地区,包括兰州、定西、甘南、青海省西宁、同仁等地市;在完善和发展观光休闲旅游的基础上,发展文化修学游、民族节庆体验游、生态休闲度假游、黄河三峡风情游、穆斯林民俗游、古生物考古游,并提出了相应的市场开发策略。 相似文献
948.
构建煤矿职业安全卫生管理体系 总被引:2,自引:0,他引:2
安全生产是煤矿企业的头等大事。根据煤矿企业的实际特点 ,分析了煤矿安全生产管理的现状、特点和煤矿建立职业安全卫生管理体系的注意事项。讨论了建立煤矿职业安全卫生管理体系的步骤和方法 相似文献
949.
强调了劳动安全卫生设计的重要性,就《废气治理环保项目劳动安全卫生设计专篇》的编写方法进行了说明。指出了环保项目中常见的危险危害因素,并提出相应的防范技术措施。 相似文献
950.
攀钢烧结烟气脱硫技术研究 总被引:10,自引:1,他引:10
介绍了攀钢烧结烟气的特点,SO2的来源。根据国内外烟气脱硫技术现状, 提出了攀钢烧结烟气脱硫的技术要求。 相似文献