国家地震紧急救援训练基地可控地震废墟设计(Ⅰ)--结构地震破坏模式

我国是一个地震多发的国家，地震灾害给我国造成了巨大的经济损失和严重的生命伤亡。专业化的震后紧急搜索救援能够最大限度地减少人民生命财产的损失，是防震减灾体系不可或缺的组成部分。通过大量的地震灾害实例，并借鉴地震灾害评估方法和建筑物抗震设计，对危害人类生命财产的建筑物震害的特征按照结构类型进行了详细说明，通过对这些地震中常见震害的了解和认识，为国家地震紧急救援训练基地的规划设计和相应搜索救援训练科目的设置提供依据。     

SIMULATED EFFECTS OF ALTERED SPILLWAY RELEASES ON THERMAL STRUCTURE AND KOKANEE GROWTH IN A COLORADO RESERVOIR1

ABSTRACT: In‐reservoir thermal and ecological effects of releasing some flows over the surface spillway at Blue Mesa Reservoir, Colorado, rather than routing all releases through the hypolimnetic outlet were evaluated using a calibrated and validated one‐dimensional thermal model (CE‐THERM) with a set of ecological models. Thermal model output indicated that surface water temperatures were influenced primarily by atmospheric conditions, but the release of warmer water over the spillway resulted in a thinner epilimnion and cooler metalimnetic water temperatures. Ecological model predictions indicated that spillway releases and associated temperatures resulted in lower growth rates for young‐of‐year (YOY) kokanee salmon (Oncorhynchus nerka) in the reservoir by up to 9 percent when compared with growth rates under baseline operations with no releases over the spillway. Kokanee growth rates were reduced under spillway release scenarios because lower temperatures not only affected metabolic rates, but limited the productivity of the zooplankton as well. Thus, altering the release regime with spillway discharges could have deleterious effects on Blue Mesa's YOY kokanee. However, in other reservoirs, distributing discharges among different elevations may provide managers with a mechanism to regulate temperatures to benefit species of concern that are facing challenges imposed by environmental conditions such as global warming.     

Intrapopulation Variation and Interpopulation Phenetic Differentiation of Chum Salmon (Oncorhynchus keta Walbaum) in Populations of the Northern Sea of Okhotsk Region

The results of phenetic studies on chum salmon populations from the rivers flowing into Taui and Yama bays, Sea of Okhotsk, are discussed. The heterogeneity of samples with respect to the frequency of a certain phene in females is not necessarily revealed when this frequency is analyzed in males. Statistically significant heterogeneity with respect to phene frequencies is observed in all chum salmon populations, whether the corresponding data are analyzed by years or throughout the observation period. This population heterogeneity is accounted for by specific phenetic features of each chum salmon population, although in different years it manifests itself in the frequencies of different phenes. The phenes distinguished on the head of fish contribute most significantly to interpopulation differences.     

GENERATION OF DAILY PRECIPITATION OVER AN AREA1

ABSTRACT: A model was developed of the periodic-stochastic structure of daily precipitation over an area. The model is based ona multivariate normal distribution. The square roots of daily precipitation at a point were found to approximate a sample from a univariate normal distribution that had been truncated at zero. The zero daily precipitation amounts were considered negative amounts of unknown quantity. The multivariate normal distribution was used to describe the variation of daily precipitation over an area. The periodic fluctuations of the model parameters were described with Fourier series. The model was tested using data from two areas of different precipitation characteristics. Data generated with the model contained many of the statistical characteristics observed in the historical data.     

火灾环境下具有弹性支座钢构件的稳定性能

根据弹性稳定理论原理研究了具有弹性支座钢结构构件在火灾环境下的静力特性问题 ,导出了高温下钢构件的静力稳定临界荷载和长度计算式 ,并讨论了温度、杆件的侧向弹簧刚度、杆长、保护层厚度等因素对杆件静力稳定临界荷载和长度的影响 ,分析表明 ,杆件的侧向弹簧刚度、杆长、保护层厚度对杆件的稳定承载力影响较大 ,并探讨了在实际工程中如何减小结构失稳的问题。     

山脊防火林带有效结构的研究

防火林带的防火性能与阻风性能密切相关。本实验采用风洞模拟方法,对通风结构、疏透结构和紧密结构3种防火林带附近的风速进行测定,绘制了3种结构防火林带迎风面的风廊线。结果表明：紧密结构与疏透结构防火林带附近的阻风性能比较好,而通风结构阻风性能最差;但紧密结构防火林带上方的相对风速高达130％,为飞火的产生创造了条件;疏透结构林带上方的最大相对风速只有110％,不具备飞火产生的条件。所以,山脊防火林带的有效结构为疏透结构。     

Managing Radioactively Contaminated Land: Implications for Habitat Diversity

Radioactive contamination of agricultural land may necessitate long-term changes in food production systems, through application of selected countermeasures, in order to reduce the accumulation of radionuclides in food. We quantified the impact of selected countermeasures on habitat diversity, using the hypothetical case of two agricultural areas in Finland. The management scenarios studied were conversions from grassland to cereal production and from grassland and crop production to afforestation. The two study sites differed with respect to present agricultural production: one being predominantly cereal production and seminatural grasslands, while the other was dominated by intensive grass and dairy production. Some of the management scenarios are expected to affect landscape structures and habitat diversity. These potential changes were assessed using a spatial pattern analysis program in connection with geographic information systems. The studied landscape changes resulted in a more monotonous landscape structure compared to the present management, by increasing the mean habitat patch size, reducing the total habitat edge length and reducing the overall habitat diversity calculated by the Shannon diversity index. The degree of change was dependent on the present agricultural management practice in the case study sites. Where dairy production was predominant, the landscape structure changes were mostly due to conversion of intensive pastures and grasslands to cereal production. In the area dominated by cereal production and seminatural grasslands, the greatest predicted impacts resulted from afforestation of meadows and pastures. The studied management changes are predicted to reduce biodiversity at the species level as well as diminishing species-rich habitats. This study has predicted prominent side effects in habitat diversity resulting from application of management scenarios. These potential long-term impacts should be considered by decision-makers when planning future strategies in the event of radionuclide deposition.     

开发我国农村人力资源的探讨

我国12.95亿人口,其中8.5亿在农村,农业滞留了我国50％以上的劳动力.农民、农村、农业这“三农”问题,是我们这一代人,乃至我们的下代都无法回避的现实问题.而探讨中国农村人力资源的开发,无疑是适应知识经济时代的到来,从人力资本理论的角度来寻求解决中国农村面临的诸多问题的迫切需要.     

对加强我国环保产品结构调整的几点思考

本文针对当前环保产业调整中存在的问题,提出了需要解决的五个方面和应处理好的几个关系。     

推进环保产业结构调整的思考

文章对环保产业结构调整要解决的问题进行了分析,指出产业结构调整必须符合市场经济要求的布局和流通结构,只有建立现代化的企业制度,企业才能有活力。