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51.
ABSTRACT

Surveys play a key role in researching public perceptions of and attitudes toward science. Accordingly, there is a breadth of often-used survey instruments available which have also been adopted for segmentation analyses. Even though many of these segmentation solutions are similar in their aims, they often include a large numbers of variables, making it more difficult for other researchers to build on these solutions, as survey time is scarce. Therefore, we demonstrate how a large number of variables that were used for a comprehensive segmentation analysis can be reduced considerably without losing too much information. We develop and test a short survey instrument to segment populations according to their attitudes toward science. Results show that segmentation results can be replicated with over 90% accuracy by reducing the instrument from 20 to 10 variables. This reduction does not significantly affect the predictive power of segment attribution on three dependent variables, which suggests that many segmentation analyses could be similarly optimized, helping researchers save survey time and standardize segmentation analyses more.  相似文献   
52.
针对西藏农牧区地域广阔、居民点分散的特点,提出一种基于表面采样-图像分割技术的快速监测方法,即在采集照片后,利用Auto CAD软件测算图像中不同类别垃圾体所占的面积,将其作为垃圾体组成比例的二维指标进行统计,研究垃圾的组成情况,并根据可降解性、材质、来源用途三种分类方法进行分类,最后得到样点垃圾组成的基本信息。  相似文献   
53.
针对污水处理运行过程COD、BOD5、TN和TP实时测量的问题,提出一种基于絮体形态参数的偏最小二乘法模型.采用图像分析技术对污泥絮体形态特征进行提取,基于相关性从提取的形态参数和试验期间的运行参数中选择模型的输入变量,通过偏最小二乘法建立输入变量与4个水质指标的预测关系模型.结果表明,COD、BOD5、TN、TP的交叉有效性系数分别为0.736、0.682、0.839、0.618,絮体形态参数与水质指标有明显的相关性,可用于预测出水水质.  相似文献   
54.
地震预报与活断层分段   总被引:1,自引:0,他引:1  
文章回顾分析了地震预报的经验与问题,对地震短期预报需进行新的探索与研讨,才能更快地前进。文章重点论述了地震预报和地震危险性评估方面有关的断层分段性问题。如何在众多的活断层上确定近期可能发生强震的地段,是地震预报中突出的重要问题之一。有关活断层分段性问题是近年来十分引人注目的课题。段是断层的破裂单元,断层的分段就是对断层进行独立的破裂单元的划分。断层分段有4种,当前讨论的主要是活断层破裂分段。  相似文献   
55.
In this work, an artificial intelligent plastic bottles classification system is proposed, developed and tested. Classifying bottles based on their chemical composition and color is attempted. Near infrared (NIR) reflectance measurements are used to identify bottle composition class. Charged coupled device (CCD) camera with the fusion of quadratic discriminant analysis (QDA) and tree classifiers are used to detect the bottle color.Results have shown that the dip wavelength and average values of the reflective NIR spectrum could be used as features to distinguish between chemical compositions. This resulted in 94.14% classification accuracy. In addition to various preprocessing techniques, the use of principal component analysis algorithm for bottle orientation facilitates the detection of the bottle color avoiding mixing it with the bottle's label or cap. Ninety-two percent color classification accuracy is achieved for clear bottles while 96% is achieved for opaque one, with proposed method. The aggregate classification accuracy of the combined system (i.e. accurate classification of color as well as chemical composition) is 83.48%.  相似文献   
56.
SEM照片孔隙参数提取技术研究   总被引:1,自引:0,他引:1  
扫描电镜技术对岩土体微观结构的分析起着越来越重要的作用,从SEM照片中获得定量化的信息参数是众多岩土工程研究者关注的问题。本文以湖南省郴州市王仙岭的黏性土SEM照片的二维和三维分析方法为例来说明SEM照片孔隙参数的提取,并对这两种方法所得结果进行分析比较,结果表明:通常采用的二维及三维分析方法所求得的孔隙率参数值往往偏大;在二维方法中合理选择分割阈值是孔隙率提取的关键,过大过小的阈值都会导致较大的误差;三维方法中需要考虑实际的颗粒形态而不能简单地按照像素值进行三维高程建模。  相似文献   
57.
安徽北部涡河断裂第四纪活动特征及地震危险性初步研究   总被引:1,自引:0,他引:1  
涡河断裂整体走向310°左右,全长约190 km,断裂在卫星影像图和区域重、磁异常图上均有明显显示,是安徽北部一条重要的第四纪活动断裂。本文通过采用高精度重力测量法和激发极化电测深法,对研究区进行物探勘测工作,确定了断裂的大致位置及产出状态,认为涡河断裂埋深150 m左右,断层宽度约为150~200 m,倾角近直立,具正断层性质。结合野外地质调查情况及前人资料,综合分析认为涡河断裂第四纪以来具有较强的活动性,是一条影响范围较广、规模较大的断裂。通过分析涡河断裂与近EW向横向构造的关系,将断裂分成北、中、南三段;结合地震空区理论分析认为南段未来发生Ms5级以上地震的危险性最大,其最大震级在5.5级与6级之间。  相似文献   
58.
The growing popularity of privatized solid waste management service in least developed countries warrants an exploration of factors that are likely to impact on its sustainability. This study takes integrated solid waste management approach by analyzing relevant issues on both market sides. We use a three step theme development sequence to analyze the data obtained on service providers through library research, observations and interviews. This was followed by an opinion survey on the demand side to elicit households’ support for service improvement. Findings show that source-separation issues, government enforcement, market segmentation, financial issues and waste disposal issues are key factors influencing improved service provision. Meanwhile, on the demand side, we found that households are willing to support proposed regulatory improvement in service provision. Thus, we suggest industrial stakeholders to consider the aforementioned supply side issues in designing future service improvements that will take advantage of existing demand side feasibility.  相似文献   
59.
目的验证一种基于遗忘因子最小二乘法(FFRLS)的含能材料反应釜温度预测模型辨识方法的正确性和有效性。方法首先利用基于机理建模方法对系统模型进行分段处理,并得到其具体结构,然后结合历史数据,利用FFRLS对系统模型参数进行辨识,最后得到含能材料反应釜温度仿真模型。结果在Matlab仿真平台上对该方法的正确性和有效性进行验证,模型参数慢时变状态下该方法辨识参数的模型参数均方根误差(RMSE)皆小于10%,模型参数突变状态下,参数RMSE最小为5.89%,最大为18.69%。结论该方法能准确、有效地对含能材料反应釜温度模型进行辨识。  相似文献   
60.
Coral reefs are highly dynamic and productive marine ecosystems, providing habitat and refuge for an enormous number of species including fish, invertebrates and algae. With increased anthropogenic pressures and global climate change, many coral reefs are rapidly declining. Currently, there is limited knowledge on condition and community assemblage composition of shallow fringing coral reefs along the south-eastern coast of Queensland, Australia. With increased demand to determine existence of coastal fringing reefs by National Regional Management groups, a rapid cost effective method to determine reef composition and condition was required. The aim of this study was to determine the benthic structure and extent of two small coastal fringing reefs (Hummock Hill Reef and Stringers Reef) along the Southern Great Barrier Reef. Reef substrate assessments were carried out using a rapid assessment technique and a Point Intercept Method (PIM). The data were analysed and classified using a Geographic Information System (GIS). Percent substrate cover was calculated using a visual basic image analysis program. The Point intercept method showed higher accuracy over the rapid assessment technique (up to 15–40% difference) and was thus deemed a more suitable classification tool for reefs with high structural complexity and heterogeneity. This study focused on piloting a rapid, cost effective Point Intercept Technique using random point count methodology to document coral benthic habitat and extent over a commonly used rapid assessment method as a tool for reef coastal management and conservation. The two techniques were compared and substrate classification success, limitations and errors were discussed.  相似文献   
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