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目前,我国城市化已进入快速发展阶段,对土地的需求越来越大,城市土地利用过程中的问题也日益突出。如何解决好经济发展与保护土地的关系,实现经济发展与土地资源可持续利用的双赢,是当前亟需解决的问题。以聊城市为例,分析了聊城市城市化的发展状况及土地利用中存在的问题,并提出了解决的措施。 相似文献
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通过对山东半岛城市群就业结构的分析,揭示出山东省城市就业结构的一般规律。从对城市群各城市的分析来看,第一产业的就业人员占据较大比重,城市化水平较低。第二产业的从业人员比重较稳定,第三产业的就业比重总体上升,但其中的传统性行业的就业比重趋于下降而新兴行业比重提高。 相似文献
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本文介绍了我国出口室内加热器类产品中暖风机在型式试验过程中常见的安全问题,指出其普遍存在的不符合标准的条款和产生的原因,并提出了解决问题的技术途径和预防措施. 相似文献
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江苏省张家港市金港中心幼儿园以"培养可持续发展的孩子,造就可持续胜任的教师,创办可持续攀高的园所,实施可持续发展的教育"为目标,在中央教科所"生态体验"课题组的引领下,坚持环境教育以人为本,弘扬"科研引领,环境潜润,体验感悟"的教育思想,将绿色教育全方位渗入幼儿的一日生活。开辟了环保展示厅、生态体验场……在环境中融进绿色的理念,发挥"润物无声胜有声"的教育功能。 相似文献
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Trametes versicolor decolorized 2000 mg L(-1) of the mono-azo substituted naphthalenic dye Amaranth with no dye sorption observed visually. The changes in the toxicity were assessed over a period of 30 d for the dye-treated viable culture, control (no dye added), and a boiled culture treated with dye, using the Microtox Acute Toxicity assay. Before dye addition, the culture filtrate had some toxicity, which increased after the dye addition. The toxicity of the dye-treated culture decreased during the treatment. The loss of toxicity occurred at the same time, with the loss of color suggesting that detoxification is associated with decoloration. The change in pH was due to natural metabolic processes and had a small effect on detoxification. Because the toxicity of the treatment was similar to that of the control at the end of the treatment, the effluent seems to be safe for release into the environment, potentially rendering this treatment suitable for industrial application. 相似文献
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城镇化是推动我国经济社会发展的重要动力,在高速发展的同时,带来大量污染排放,威胁乡村环境质量与可持续发展。在对乡村生态环境问题剖析的基础上,从战略、实施、方式等层面探索解决思路,围绕科学规划、发展方式、基础建设、管理机制、宣传教育等方面分析关键点,加强乡村环境保护,保障城镇化建设健康发展,为促进农村农业持续发展提供持久动力。 相似文献
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泵站树状给水管网流量具有随机性,而这种随机性变化会直接影响管网的建设费用和动力费用.针对这-特点,应用随机规划原理,建立泵站树状给水管网机会约束模型,编写基于随机模拟的遗传算法程序求解该模型.机会约束模型能较客观地反映该管网的实际工况,使优化设计结果更符合实际. 相似文献
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Sudipta B. Sarmah B. Das A. Garg L. Gao R. K. Pai 《International Journal of Green Energy》2020,17(8):510-520
ABSTRACT Estimation of State of Health (SoH) of Lithium-ion (Li-ion) battery is essential to predict the lifespan of batteries of an electric vehicle (EV). The efficient prediction of battery health indicates to the effective and safe operation of EV. However, delivering an effective and accurate method for the estimation of SoH in the real condition is truly a challenging task. The present study proposed a holistic procedure of combining both experimental and numerical investigations to conduct the fundamental study on coupled mechanical-electrochemical behavior of Li-ion battery. The proposed investigation highlighted the effect of stress on the capacity of the battery, considering capacity fade as an equivalent parameter to its health for real-time estimation of SoH. Finally, a simple model of Artificial Neural Network (ANN) is provided, which shows the linear dependency of stress with the SoH. The results obtained from the ANN model are validated with a Linear Regression (LR) model for a better understanding of the inspection. The predicted value of mean Square Error (MSE) and R square error in the ANN training model are found to be 0.000309 and 0.849687, respectively. Whereas for the test model, these predicted values are found to be 0.000438 and 0.819347, respectively. 相似文献
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A previous study using respondents in a London regional audience appreciation diary panel showed that links existed between overall amounts of the viewing of television recorded across one week and levels of perception of risk of three hazards to life, namely lightning, flooding and terrorist bomb attacks. With a fourth hazard, cancer, there was an inverted U-shaped relationship between perceived risk level and amount of viewing. At the same time there were no relationships between amounts of viewing of news and documentary material and perceived risks of any of 12 hazards. Two new surveys were done, nearly three years after the previous one, asking people in widely different regions about their perceptions of nine various hazards, and linking these results with measures of attitudes towards certain adaptations of new technology (which could prove hazardous or beneficial according to points of view) and to patterns of television viewing. The two surveys agreed on a wide number of points with each other; they agreed with the previous study in finding no steady relationships between information programme viewing and hazard perception. Lightning and flooding were again related, this time more specifically with viewing of particular types of television programming. A new finding is that heavier viewing of television sport is associated with less perceived risk of cancer and of nuclear pollution. Interpretations are generally favoured along the lines of a selective process of viewers with certain predispositions choosing certain kinds of viewing patterns, rather than that programme contents provide an example for formulating perceptions and attitudes. 相似文献
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开发白洋淀旅游资源的制约因素与对策 总被引:2,自引:0,他引:2
作者在实地调查研究的基础上,认为制约白洋淀旅游业发展的因素主要有水位不稳、水质受到污染、旅游项目内容贫乏、参与性差、景区文化氛围不和谐,以及管理不到位。作者提出,应努力保持其水位稳定,加强流域内污染治理,理顺管理体制,建立白洋淀湿地保护区,加大旅游资源开发和宣传力度,丰富旅游的文化内涵等来保证白洋淀旅游的可持续发展。 相似文献