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Problem and Countermeasure of Rural Domestic Sewage Treatment 被引量:3
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作者 曲丽丽 李悦 +2 位作者 孔范龙 赵丽霞 孙鹏 《Agricultural Science & Technology》 CAS 2012年第12期2620-2622,共3页
With the development of rural economy, pollutions of rural sewage are in- creasingly serious. This paper introduces the characteristics of rural domestic sewage and the rural sewage treatment situation, and according ... With the development of rural economy, pollutions of rural sewage are in- creasingly serious. This paper introduces the characteristics of rural domestic sewage and the rural sewage treatment situation, and according to the problems of funds, management, process selection, policy and weak awareness of environmental protection in the rural domestic sewage treatment, puts forward relevant countermea- sures to ensure long-term operation of sewage treatment system, and achieve the purpose of improving rural water environment and protect the ecological environment in rural areas. 展开更多
关键词 Rural domestic sewage treatment PROBLEM COUNTERMEASURES
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Problems and Strategies for Arable Land Eco-conservation in China 被引量:2
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作者 杨诗琴 杨子生 《Agricultural Science & Technology》 CAS 2017年第7期1355-1357,1360,共4页
Arable lands are so important to China concerning food security and ec- onomy development. And eco-problems are rising and food security risks are widespread. The research reviewed quantity and quality of domestic ara... Arable lands are so important to China concerning food security and ec- onomy development. And eco-problems are rising and food security risks are widespread. The research reviewed quantity and quality of domestic arable lands, analyzed existing problems and proposed countermeasures for reinforcing domestic arable land conservation. 展开更多
关键词 Arable land Eco-conservation Existing problems STRATEGIES China
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浅谈技工学校“问题”学生的教育转化
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作者 邢雅娜 冯苗迪 《才智》 2014年第22期165-165,共1页
技工学校担负着为企业培养和输送适应生产、服务第一线的具有中高级技术技能的应用型人才的重任,直接为经济建设和劳动就业服务。但是近年来由于各种原因,导致技工学校生源的综合素质逐年下降,"问题"学生占每年入校新生的比... 技工学校担负着为企业培养和输送适应生产、服务第一线的具有中高级技术技能的应用型人才的重任,直接为经济建设和劳动就业服务。但是近年来由于各种原因,导致技工学校生源的综合素质逐年下降,"问题"学生占每年入校新生的比例逐年上升。要搞好职业教育工作,完成技工学校肩负的重任,就必须在思考这些学生有"问题"的原因之下,重视对这些"问题"生进行心理教育,从而循序渐进、有的放矢地采取各种措施和方法,做好对"问题"生的教育转化工作,使其成为合格的毕业生,这对于做好职业教育工作是非常重要的。 展开更多
关键词 职业教育 “问题”生 教育转化 弹性教育法
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The Main Problems and Countermeasures of Agricultural Ecological Environment in Guangxi Province
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作者 刘静静 覃朝科 《Agricultural Science & Technology》 CAS 2015年第5期1056-1059,共4页
Guangxi Province is a large agricultural province and agricultural eco-environment protection becomes important. The research analyzed major problems of agricultural eco-environment and proposed a series of countermea... Guangxi Province is a large agricultural province and agricultural eco-environment protection becomes important. The research analyzed major problems of agricultural eco-environment and proposed a series of countermeasures to improve Guangxi agricultural eco-environment and provides references for agricultural eco-environment protection in Guangxi and agricultural development. 展开更多
关键词 Agricultural eco-environment Problem COUNTERMEASURES
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Ecological Environment Problems and Countermeasures of Small and Middle-sized Rivers in Shandong Province
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作者 赵维军 彭淑贞 +3 位作者 燕婷婷 张伟 张莹 宋晓鹏 《Agricultural Science & Technology》 CAS 2016年第10期2369-2372,共4页
Water uses in small and middle-sized rivers, and non-ecological treatment model has deteriorated local environment in Shandong. The research reviewed ecological environment status quo of small and middle rivers and co... Water uses in small and middle-sized rivers, and non-ecological treatment model has deteriorated local environment in Shandong. The research reviewed ecological environment status quo of small and middle rivers and concluded existing problems. Finally, ecological treatments were proposed based on treatments at home and abroad in order to improve eco-environment of rivers and build better Shandong. 展开更多
关键词 ECO-ENVIRONMENT Small and middle-sized rivers Problems and Countermeasures Shandong Province
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Problems and Countermeasures of the Bio-energy Development in China
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作者 徐优 王学华 《Agricultural Science & Technology》 CAS 2014年第5期718-723,共6页
The current development and utilization status of bio-energy at home and abroad was summarized, and a multi-angle in-depth analysis and reflection was given to the problems encountered in the development of bio-energy... The current development and utilization status of bio-energy at home and abroad was summarized, and a multi-angle in-depth analysis and reflection was given to the problems encountered in the development of bio-energy. Furthermore, some suggestions were put forward to accelerate the further development of bio-en-ergy industry in China. 展开更多
关键词 Biology energy Development status Problems and countermeasures
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The Design and Control of Distillation Column with Side Reactors for Chlorobenzene Production 被引量:6
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作者 薄翠梅 汤吉海 +3 位作者 柏杨进 乔旭 丁良辉 张湜 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第6期1113-1120,共8页
The distillation column with side reactors (SRC) can overcome the temperature/pressure mismatch in the traditional reactive distillation, the column operates at temperature/pressure favorable for vapor-liquid separati... The distillation column with side reactors (SRC) can overcome the temperature/pressure mismatch in the traditional reactive distillation, the column operates at temperature/pressure favorable for vapor-liquid separation, while the reactors operate at temperatures/pressures favorable for reaction kinetics. According to the smooth operation and automatic control problem of the distillation column with side reactors (SRC), the design, simulation calculation and dynamic control of the SCR process for chlorobenzene production are discussed in the paper. Firstly, the mechanism models, the integrated structure optimal design and process simulation systems are established, respectively. And then multivariable control schemes are designed, the controllability of SRC process based on the optimal steady-state integrated structure is explored. The dynamic response performances of closed-loop system against several disturbances are discussed to verify the effectiveness of control schemes for the SRC process. The simulating results show that the control structure using conventional control strategies can effectively overcome feeding disturbances in a specific range. 展开更多
关键词 distillation column with side reactors (SRC) mechanism models multivariable control schemes simula- tion system chlorobenzene production
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Heart failure in the elderly 被引量:8
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作者 Pablo Diez-Villanueva Femando Alfonso 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第2期115-117,共3页
Heart failure (HF) is a major public health problem worldwide entailing high morbidity and mortality as well as high costs. This chronic syndrome associates with a low functional status and quality of life. Most pa... Heart failure (HF) is a major public health problem worldwide entailing high morbidity and mortality as well as high costs. This chronic syndrome associates with a low functional status and quality of life. Most patients with HF are elderly, constituting up to 80% of patients suffering from this disease with both incidence and prevalence of the condition increasing with age. This is due to the progressive aging of the population as well as improved and better survival after cardiac insults, such as myocardial infarction, 展开更多
关键词 ELDERLY Heart failure PROGNOSIS
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Quantum Dots for Cancer Research:Current Status,Remaining Issues,and Future Perspectives 被引量:4
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作者 Min Fang Chun-wei Peng +1 位作者 Dai-Wen Pang Yan Li 《Clinical oncology and cancer researeh》 CAS CSCD 2012年第3期151-163,共13页
Cancer is a major threat to public health in the 21st century because it is one of the leading causes of death worldwide.The mechanisms of carcinogenesis,cancer invasion,and metastasis remain unclear.Thus,the developm... Cancer is a major threat to public health in the 21st century because it is one of the leading causes of death worldwide.The mechanisms of carcinogenesis,cancer invasion,and metastasis remain unclear.Thus,the development of a novel approach for cancer detection is urgent,and real-time monitoring is crucial in revealing its underlying biological mechanisms.With the optical and chemical advantages of quantum dots(QDs),QD-based nanotechnology is helpful in constructing a biomedical imaging platform for cancer behavior study.This review mainly focuses on the application of QD-based nanotechnology in cancer cell imaging and tumor microenvironment studies both in vivo and in vitro,as well as the remaining issues and future perspectives. 展开更多
关键词 quantum dots molecular imaging multimodality probes
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Comorbidity in inflammatory bowel disease 被引量:3
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作者 Antonio López San Román Fernando Muoz 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第22期2723-2733,共11页
Patients with inflammatory bowel disease (IBD) can be affected by other unrelated diseases. These are called comorbid conditions, and can include any secondary health problem that affects a person suffering from a pri... Patients with inflammatory bowel disease (IBD) can be affected by other unrelated diseases. These are called comorbid conditions, and can include any secondary health problem that affects a person suffering from a primary or main disease, and which is neither linked physiopathologically to the primary condition, nor is it due to the treatments used for the primary condition or to its long-term anatomical or physiological consequences. Different comorbid conditions, as well as their influence on IBD, are discussed. 展开更多
关键词 COMORBIDITY Comorbid conditions Crohn’ disease Inflammatory bowel disease Ulcerative colitis
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Genetic Algorithm Based on Duality Principle for Bilevel Programming Problem in Steel-making Production 被引量:2
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作者 林硕 栾方军 +3 位作者 韩忠华 吕希胜 周晓锋 刘炜 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期742-747,共6页
Steel-making and continuous/ingot casting are the key processes of modern iron and steel enterprises. Bilevel programming problems(BLPPs) are the optimization problems with hierarchical structure. In steel-making prod... Steel-making and continuous/ingot casting are the key processes of modern iron and steel enterprises. Bilevel programming problems(BLPPs) are the optimization problems with hierarchical structure. In steel-making production, the plan is not only decided by the steel-making scheduling, but also by the transportation equipment.This paper proposes a genetic algorithm to solve continuous and ingot casting scheduling problems. Based on the characteristics of the problems involved, a genetic algorithm is proposed for solving the bilevel programming problem in steel-making production. Furthermore, based on the simplex method, a new crossover operator is designed to improve the efficiency of the genetic algorithm. Finally, the convergence is analyzed. Using actual data the validity of the proposed algorithm is proved and the application results in the steel plant are analyzed. 展开更多
关键词 Steel-making Genetic algorithm Bilevel problem SCHEDULING
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Edible Peanut Worm(Sipunculus nudus) in the Beibu Gulf: Resource, Aquaculture, Ecological Impact and Counterplan 被引量:10
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作者 LI Junwei XIE Xiaoyong +2 位作者 ZHU Changbo GUO Yongjian CHEN Suwen 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第5期823-830,共8页
Sipunculus nudus is an important economic species because of its high nutritional and medicinal values. The exploitation and utilization of S. nudus primarily occur in the coastal regions of the Beibu Gulf. However, w... Sipunculus nudus is an important economic species because of its high nutritional and medicinal values. The exploitation and utilization of S. nudus primarily occur in the coastal regions of the Beibu Gulf. However, wild resource of S. nudus is rapidly decreasing because of the overexploitation, which has led to considerable developments of artificial breeding techniques. The cultivation scale of S. nudus has increased in response to successful artificial breeding; however, methods for culturing S. nudus in tidal flats or ponds require further study. Most studies have focused on the breeding, nutrition, medical value and ecological impact of these worms. Studies on the distribution, sediment requirements, nutrition characteristics, breeding techniques and aquaculture ecology of this species are summarized in this paper to promote the development of the aquaculture industry for S. nudus. The high biomass of S. nudus in the Beibu Gulf is positively correlated with the sediment characteristics and water quality of the region. The production of peanut worm has improved to some extent through culturing; however, the nutrient value and ecological environment problems have been observed, which reflect the over exploitation of trace elements and the sediment. These problems will worsen unless they are resolved, and the release of organic materials, nitrogen and phosphorus during harvesting impacts the coastal environment. Moreover, genetic erosion is a potential risk for larvae in artificial breeding programs in tidal flats. Therefore, culturing and collecting methods should be improved and the wild resource conservation should be implemented to promote the sustainable development of the peanut worm. 展开更多
关键词 breeding larvae aquaculture tidal nutrition cultivation erosion exploitation sustainable phosphorus
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Celiac disease in the developing countries: A new and challenging public health problem 被引量:16
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作者 Francesco Cataldo Giuseppe Montalto 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第15期2153-2159,共7页
In the past, celiac disease was believed to be a chronic enteropathy, almost exclusively affecting people of European origin. The availability of new, simple, very sensitive and specific serological tests (anti-gliad... In the past, celiac disease was believed to be a chronic enteropathy, almost exclusively affecting people of European origin. The availability of new, simple, very sensitive and specific serological tests (anti-gliadin, anti- endomysium and anti-transglutaminase antibody assays) have shown that celiac disease is common not only in Europe and in people of European ancestry but also in the developing countries where the major staple diet is wheat (Southern Asia, the Middle East, North West and East Africa, South America), both in the general population and in the groups at risk. Gluten intolerance thus appears to be a widespread public health problem and an increased level of awareness and clinical suspicion are needed in the New World where physicians must learn to recognize the variable clinical presentations (classical, atypical and silent forms) of celiac disease. In the developing countries, both serological screening in the general population and serological testing in groups at risk are necessary for an early identification of celiac patients. The gluten-free diet poses a challenging public health problem in the developing countries, especially since commercial gluten-free products are not available. 展开更多
关键词 Celiac disease Developing countries
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Worldwide epidemiology of liver hydatidosis including the Mediterranean area 被引量:36
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作者 Giuseppe Grosso Salvatore Gruttadauria +2 位作者 Antonio Biondi Stefano Marventano Antonio Mistretta 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第13期1425-1437,共13页
The worldwide incidence and prevalence of cystic echinococcosis have fallen dramatically over the past several decades.Nonetheless,infection with Echinococcus granulosus(E.granulosus)remains a major public health issu... The worldwide incidence and prevalence of cystic echinococcosis have fallen dramatically over the past several decades.Nonetheless,infection with Echinococcus granulosus(E.granulosus)remains a major public health issue in several countries and regions,even in places where it was previously at low levels,as a result of a reduction of control programmes due to economic problems and lack of resources.Geographic distribution differs by country and region depending on the presence in that country of large numbers of nomadic or semi-nomadic sheep and goat flocks that represent the intermediate host of the parasite,and their close contact with the final host,the dog,which mostly provides the transmission of infection to humans.The greatest prevalence of cystic echinococcosis in human and animal hosts is found in countries of the temperate zones,including several parts of Eurasia(the Mediterranean regions,southern and central parts of Russia,central Asia,China),Australia,some parts of America(especially South America)and north and east Africa.Echinococcosis is currently considered an endemic zoonotic disease in the Mediterranean region.The most frequent strain associated with human cystic echinococcosis appears to be the common sheep strain(G1).This strain appears to be widely distributed in all continents.The purpose of this review is to examine the distribution of E.granulosus and the epidemiology of a re-emerging disease such as cystic echinococcosis. 展开更多
关键词 Epidemiology Echinococcus granu/osus Cystic echinococcosis
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The Main Ecological Issues of Water-Level -Fluctuating Zone and The strategies in Three Gorges Reservoir Area 被引量:4
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作者 Weici Su Jinping Liu +1 位作者 Hua Yang Junyi Zhang 《Journal of Environmental Science and Engineering》 2010年第1期77-82,共6页
After the completion of the Three Gorges dam, a 30 m high water-level-fluctuating zone (WLFZ) will appear along the banks, and will form a seasonal wetland ecosystem. According to the program of storing water in the... After the completion of the Three Gorges dam, a 30 m high water-level-fluctuating zone (WLFZ) will appear along the banks, and will form a seasonal wetland ecosystem. According to the program of storing water in the Three Gorges reservoir, the main ecological and environmental problems probably incurred in WLFZ are discussed, such as formation of contaminated belt along banks, appearance of epidemic diseases in the reservoir region (including urban districts), aggravation of geologic disasters, degradation of biodiversity and exacerbation of the ecosystem vulnerability. Six items of strategies are put forward according to the causes, distributed features and trends of these problems in this paper. 展开更多
关键词 Water-level-fluctuating zone ecological problems STRATEGIES Three Gorges reservoir region.
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Spatially Different Nutrient Histories Recorded by Multiple Cores and Implications for Management in Taihu Lake, Eastern China 被引量:4
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作者 CAO Yanmin ZHANG Enlou +2 位作者 Peter LANGDON LIU Enfeng SHEN Ji 《Chinese Geographical Science》 SCIE CSCD 2013年第5期537-549,共13页
The Taihu Lake,a large shallow lake in the floodplain of the Changjiang(Yangtze) River in the eastern China,is faced with challenging ecological problems resulting from eutrophication,which has affected the regional f... The Taihu Lake,a large shallow lake in the floodplain of the Changjiang(Yangtze) River in the eastern China,is faced with challenging ecological problems resulting from eutrophication,which has affected the regional freshwater supply of a large population.Although efforts have been made to assess the nutrient evolution histories in the northern bays,little is known regarding nutrient histories in different parts across the entire lake basin.In this paper,we present nutrient histories for different parts of the lake based on chironomid transfer functions applied to four short cores obtained from the northern,western and eastern regions of the lake.The chironomid-inferred total phosphorus(CI-TP) concentrations were compared with the phosphorus concentrations obtained by using instrumental and sedimentary data.The results suggest that trophic evolution histories were asynchronous throughout the lake during the past decades in response to different ecological regimes controlled by the nutrient input,wind direction and shoreline topography.The restoration of aquatic plants may be an effective option for the management of lake rehabilitation to ′natural′ conditions.Given the multiple factors controlling the biotic communities in such a large and complex lake,combined analyses among the multi-proxies encountered in the sediments are necessary for comprehensive insight into paleolimnological studies.The spatial heterogeneity in the ecological trajectories within this complicated ecosystem suggests that different management practices should be undertaken for specific lake zones in the Taihu Lake. 展开更多
关键词 nutrient history CHIRONOMID multiple cores transfer function Taihu Lake
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Crimean-Congo Hemorrhagic Fever: An Overview 被引量:1
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作者 Serkan ncü 《Virologica Sinica》 SCIE CAS CSCD 2013年第4期193-201,共9页
Crimean-Congo hemorrhagic fever (CCHF) is a zoonotic viral infection that is a serious threat to humans. The disease is widely distributed in Africa, Asia, and Europe and has developed into a serious public health con... Crimean-Congo hemorrhagic fever (CCHF) is a zoonotic viral infection that is a serious threat to humans. The disease is widely distributed in Africa, Asia, and Europe and has developed into a serious public health concern. Humans become infected through the bites of ticks, by contact with a patient with CCHF, or by contact with blood or tissues from viremic livestock. Microvascular instability and impaired hemostasis are the hallmarks of the infection. Infection in human begins with nonspecific febrile symptoms, but may progress to a serious hemorrhagic syndrome with high mortality rates. Enzyme-linked immunoassay (ELISA) and polymerase chain reaction (PCR) are the most used and specific tests for the diagnosis. The mainstay of treatment is supportive. Although definitive studies are not available, ribavirin is suggested to be effective especially at the earlier phase of the infection. Uses of universal protective measures are the best way to avoid the infection. In this review, all aspects of CCHF are overviewed in light of the current literature. 展开更多
关键词 Crimean-Congo Hemorrhagic Fever EPIDEMIOLOGY TRANSMISSION PATHOGENESIS DIAGNOSIS Treatment PREVENTION
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Analysis of the psychological conditions and related factors of breast cancer patients 被引量:4
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作者 Guilin Huang Yiping Wu +2 位作者 Guiqing Zhang Pinghua Zhang Jie Gao 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第1期53-57,共5页
Sufferers of breast cancer are often plagued by various psychological problems. Mastectomy, which has a serious influence on the female sex characteristics, can bring about especially serious psychological problems. T... Sufferers of breast cancer are often plagued by various psychological problems. Mastectomy, which has a serious influence on the female sex characteristics, can bring about especially serious psychological problems. These problems affect not only the patients’ quality of life but also the beginning, development, and end of the disease. This paper reviewed the relationships between the patients’ personal factors, the disease itself, treatment factors, and other socio-psychological factors and psychological conditions so as to provide new ideas for the psychological intervention on breast cancer patients, comprehensive clinical diagnosis and treatment, and prevention and cure. 展开更多
关键词 breast cancer psychological conditions related factors
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Preliminary Study on Early-warning System of Ecological Security in Water-Level-Fluctuating Zone (WLFZ) of Three Gorges Reservoir 被引量:2
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作者 郑磊 左太安 李月臣 《Agricultural Science & Technology》 CAS 2010年第5期159-164,共6页
The area,the scope as well as some ecological environment questions in Three Gorges Reservoir was briefly introduced. Then its early warning-system frame was preliminarily constructed,which includes ecological securit... The area,the scope as well as some ecological environment questions in Three Gorges Reservoir was briefly introduced. Then its early warning-system frame was preliminarily constructed,which includes ecological security dynamic monitoring,ecological security appraisal,ecological security forecast and ecological security decision-making management. The synthetic evaluation indicator system of the ecological security quality were initially established,which includes ecological environment pollution,land use and land cover change,geological hazard and epidemic outbreaks. At the same time,29 evaluating indicators were selected,divides into the basic factors,response factors and inducing factors,which need to be Real-time monitored. 展开更多
关键词 Ecological security Early warning system Fuzzy mathematics Three Gorges Reservoir Water-Level-Fluctuating Zone (WLFZ)
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A linear programming model for long-term mine planning in the presence of grade uncertainty and a stockpile 被引量:5
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作者 Koushavand Behrang Askari-Nasab Hooman Deutsch Clayton V. 《International Journal of Mining Science and Technology》 SCIE EI 2014年第4期451-459,共9页
The complexity of an open pit production scheduling problem is increased by grade uncertainty. A method is presented to calculate the cost of uncertainty in a production schedule based on deviations from the target pr... The complexity of an open pit production scheduling problem is increased by grade uncertainty. A method is presented to calculate the cost of uncertainty in a production schedule based on deviations from the target production. A mixed integer linear programming algorithm is formulated to find the min- ing sequence of blocks from a predefined pit shell and their respective destinations, with two objectives: to maximize the net present value of the operation and to minimize the cost of uncertainty. An efficient clustering technique reduces the number of var/ables to make the problem tractable. Also, the parameters that control the importance of uncertainty in the optimization problem are studied. The minimum annual mining capacity in presence of grade uncertainty is assessed. The method is illustrated with an oil sand deposit in northern Alberta. 展开更多
关键词 Production scheduling Ceostatistics Conditional simulation Kriging Cost of uncertainty
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