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Evaluation of Economical and Intensive Use of Construction Land in a County Town:A case study of Wan’an County,Ji’an City
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作者 YU Zhijie 《Journal of Landscape Research》 2024年第1期51-54,共4页
Taking the changes of construction land in Wan’an County over the years as the research object,the quantity and spatial characteristics of construction land in Wan’an County were analyzed,and the overall situation a... Taking the changes of construction land in Wan’an County over the years as the research object,the quantity and spatial characteristics of construction land in Wan’an County were analyzed,and the overall situation and regional differences of construction land utilization in Wan’an County were revealed.From the aspects of main influencing factors such as land use structure,land use intensity,land input intensity and output benefit,an evaluation indicator system was established to evaluate the economical and intensive use level of construction land in Wan’an County.The results show that the score of the economical and intensive use level of construction land in Wan’an County was 56.92,which was the lowest among all the districts and counties in Ji’an City.Based on the evaluation results,the corresponding economizing and intensive strategies were put forward,and the safeguard measures for its implementation were explored.The purpose is to provide some support for the preparation of territorial spatial planning,the delineation of urban development boundaries,and the potential exploitation of construction land stock,hoping to improve the utilization efficiency and benefit of construction land in Wan’an County,and promote the economic growth of Wan’an County to the stage of high-quality development. 展开更多
关键词 Construction land economical and intensive utilization EVALUATION
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A Reference Vector-Assisted Many-Objective Optimization Algorithm with Adaptive Niche Dominance Relation
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作者 Fangzhen Ge Yating Wu +1 位作者 Debao Chen Longfeng Shen 《Intelligent Automation & Soft Computing》 2024年第2期189-211,共23页
It is still a huge challenge for traditional Pareto-dominatedmany-objective optimization algorithms to solve manyobjective optimization problems because these algorithms hardly maintain the balance between convergence... It is still a huge challenge for traditional Pareto-dominatedmany-objective optimization algorithms to solve manyobjective optimization problems because these algorithms hardly maintain the balance between convergence and diversity and can only find a group of solutions focused on a small area on the Pareto front,resulting in poor performance of those algorithms.For this reason,we propose a reference vector-assisted algorithmwith an adaptive niche dominance relation,for short MaOEA-AR.The new dominance relation forms a niche based on the angle between candidate solutions.By comparing these solutions,the solutionwith the best convergence is found to be the non-dominated solution to improve the selection pressure.In reproduction,a mutation strategy of k-bit crossover and hybrid mutation is used to generate high-quality offspring.On 23 test problems with up to 15-objective,we compared the proposed algorithm with five state-of-the-art algorithms.The experimental results verified that the proposed algorithm is competitive. 展开更多
关键词 Many-objective optimization evolutionary algorithm Pareto dominance reference vector adaptive niche
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Vector Dominance with Threshold Searchable Encryption (VDTSE) for the Internet of Things
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作者 Jingjing Nie Zhenhua Chen 《Computers, Materials & Continua》 SCIE EI 2024年第6期4763-4779,共17页
The Internet of Medical Things(IoMT)is an application of the Internet of Things(IoT)in the medical field.It is a cutting-edge technique that connects medical sensors and their applications to healthcare systems,which ... The Internet of Medical Things(IoMT)is an application of the Internet of Things(IoT)in the medical field.It is a cutting-edge technique that connects medical sensors and their applications to healthcare systems,which is essential in smart healthcare.However,Personal Health Records(PHRs)are normally kept in public cloud servers controlled by IoMT service providers,so privacy and security incidents may be frequent.Fortunately,Searchable Encryption(SE),which can be used to execute queries on encrypted data,can address the issue above.Nevertheless,most existing SE schemes cannot solve the vector dominance threshold problem.In response to this,we present a SE scheme called Vector Dominance with Threshold Searchable Encryption(VDTSE)in this study.We use a Lagrangian polynomial technique and convert the vector dominance threshold problem into a constraint that the number of two equal-length vectors’corresponding bits excluding wildcards is not less than a threshold t.Then,we solve the problem using the proposed technique modified in Hidden Vector Encryption(HVE).This technique makes the trapdoor size linear to the number of attributes and thus much smaller than that of other similar SE schemes.A rigorous experimental analysis of a specific application for privacy-preserving diabetes demonstrates the feasibility of the proposed VDTSE scheme. 展开更多
关键词 Internet of Things(IoT) Internet of Medical Things(IoMT) vector dominance with threshold searchable encryption(VDTSE) threshold comparison electronic healthcare
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开发区升格政策能促进企业创新增量提质吗?
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作者 张帅 王筱依 《太原学院学报(社会科学版)》 2025年第1期92-106,共15页
通过构建多时点DID模型实证检验开发区升格政策对企业创新数量和创新质量的影响,结果表明:省级开发区升格通过降低制度性交易成本、提升市场化程度和加速创新要素流入对企业创新产出数量和产出质量产生促进作用,该政策对非民营企业、非... 通过构建多时点DID模型实证检验开发区升格政策对企业创新数量和创新质量的影响,结果表明:省级开发区升格通过降低制度性交易成本、提升市场化程度和加速创新要素流入对企业创新产出数量和产出质量产生促进作用,该政策对非民营企业、非高技术制造行业、高新区和小规模城市的作用效果更强。因此,要充分发挥开发区“以升促建”的创新激励效应,不仅要注重有为政府和有效市场的结合,还要根据城市固有经济特征优化开发区制度环境。 展开更多
关键词 开发区升格 创新数量 创新质量
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The Distribution of Eigenvance of Product Diagonal Dominance Matrix 被引量:1
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作者 杨益民 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期32-40,共9页
Let DD_0(R)={A∈C^(n×#)||Rea_(ii)Rea_(jj)|≥A_iA_j,i≠j,i,j∈N}.PD_0(R)={A∈C^(n×#)||Rea_(ii)Rea_(kk)|≥A_iA_jA_k,i≠j≠k,i,j,k∈N}. In this paper,we show DD_0(R)PD_0(R),and the conditions under which the nu... Let DD_0(R)={A∈C^(n×#)||Rea_(ii)Rea_(jj)|≥A_iA_j,i≠j,i,j∈N}.PD_0(R)={A∈C^(n×#)||Rea_(ii)Rea_(kk)|≥A_iA_jA_k,i≠j≠k,i,j,k∈N}. In this paper,we show DD_0(R)PD_0(R),and the conditions under which the numbers of eigen vance of A∈PD_0(R)\DD_0(R)are equal to the numbers of a_(ii),i∈N in positive and negative real part respectively.Some couter examples are given which present the condnions can not be omitted. 展开更多
关键词 MATRIX diagonal dominance EIGENVALUE DISTRIBUTION
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Studies on the Economical and Practical Temperature Control Facility of Deep-Litter Systems for Swine Production
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作者 林家彬 秦竹 +5 位作者 周忠凯 顾洪如 杨杰 汤赤 陈俊 余刚 《Agricultural Science & Technology》 CAS 2013年第7期1053-1056,共4页
Deep-Litter System is a high yield approach to raise swine with pollution free in a lower cost. In the research, based on the heat stress in summer caused by fermentation, three temperature-control systems were design... Deep-Litter System is a high yield approach to raise swine with pollution free in a lower cost. In the research, based on the heat stress in summer caused by fermentation, three temperature-control systems were designed, including natural ventilation through transoms, forced ventilation via fans, and cooling by hyperbaric spray system. Specifically, the latter intermittent auto-pressurized spray system developed in our lab, which could spray successively via pressure from storage tubes without wetting the fermentation bed, is suitable for the promotion with the deep-litter technology in rural regions , since the power consumption is only 1 kwh per day. 展开更多
关键词 Deep litter system Temperature control facilities Intermittent auto-pressurized spray system economical and practical
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Analysis on the Economical and Intensive Utilization of Regional Construction Land in Zunyi City of Guizhou Province
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作者 兰安军 王昌浩 +1 位作者 钟九生 秦微 《Agricultural Science & Technology》 CAS 2017年第6期1133-1137,共5页
Taking Zunyi City of Guizhou Province as research area, the research performed spatial dynamic analysis and elastic coefficient method to evaluate the e- conomical and intensive utilization of the regional constructio... Taking Zunyi City of Guizhou Province as research area, the research performed spatial dynamic analysis and elastic coefficient method to evaluate the e- conomical and intensive utilization of the regional construction land, and to discuss the decision direction for economical and intensive utilization of the regional con- struction land. The results showed that, the population based land utilization both in Zunyi and the city districts and counties indicated extensive trend. The economy- based land utilization in Zunyi City, as well as in Huichun, Zunyi and Tongzi County presented intensive trend, however the other districts and counties were in extensive tendency. It concluded that the economical and intensive utilization of construction land should be focused on the rural collective construction land, and the potential tapping of rural collective construction land in rocky desertification area should be the first priority, otherwise, the regional economic development was unbalanced be- tween different district and county in Zunyi. 展开更多
关键词 economical and intensive utilization Elastic coefficient Spatial dynamicanalysis Zunyi City
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Analysis of the Species Dominance & Dominant on the Karst Mountain Grassland Plant Community 被引量:4
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作者 张文 张建利 《Agricultural Science & Technology》 CAS 2011年第7期1020-1024,共5页
[Objective] The aim was to study the species,quantity and community traits of dominant plant in karst mountain grassland plant community so as to provide support for the vegetation restoration in karst mountain grassl... [Objective] The aim was to study the species,quantity and community traits of dominant plant in karst mountain grassland plant community so as to provide support for the vegetation restoration in karst mountain grassland.[Method] Standard plot sites investigation method was used study the quantity traits of different plant communities of different altitudes and slopes.[Result] The IV SDR4 were the highest in the all plot sites of plant community on the kasrt mountain grassland,but the IV SDR4 were showed a trend of decreasing with the increasing of the altitude.The dominant quantity was increasing with the altitude upward,so the altitude was the mostly factor for plant community construction.[Conclusion] Altitude was the main factor to influence the community structure of plant. 展开更多
关键词 KARST Grassland plant COMMUNITY Species dominance DOMINANT
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基于改进K-dominance的服务评价与优选
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作者 赵卓 丁建民 《计算机系统应用》 2014年第7期195-200,共6页
在动态、开放的云计算环境中,越来越多互有竞争关系的服务提供商以不同的服务质量等级提供功能相同或类似的服务,这使得基于QoS的服务优选变得愈加重要.考虑到传统方法的不足,提出一个完整的方法解决这一多目标优化问题.首先,提出一个... 在动态、开放的云计算环境中,越来越多互有竞争关系的服务提供商以不同的服务质量等级提供功能相同或类似的服务,这使得基于QoS的服务优选变得愈加重要.考虑到传统方法的不足,提出一个完整的方法解决这一多目标优化问题.首先,提出一个新的概念:partial dominance score,用于针对skyline计算得到的最优解(skyline服务集合)实现进一步更为精确的量化评价,在此基础上重新定义了服务优选问题的优化目标.随后提出一个基于BNL策略的服务优选算法高效地返回partial dominance score意义上的top-k最优skyline服务,从而为用户的最终决策和优选提供有效的支持.通过一系列实验验证了所提出算法的效率和有效性. 展开更多
关键词 云计算 服务评价 服务等级协议 多目标决策 帕累托优化
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China's regional transport dominance: Density, proximity, and accessibility 被引量:59
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作者 JIN Fengjun WANG Chengjin LI Xiuwei WANG Jiao'e 《Journal of Geographical Sciences》 SCIE CSCD 2010年第2期295-309,共15页
Transport infrastructure plays an important role in shaping the configuration of spatial socio-economic structures and influences regional accessibility. This paper defines transport dominance from three aspects: qua... Transport infrastructure plays an important role in shaping the configuration of spatial socio-economic structures and influences regional accessibility. This paper defines transport dominance from three aspects: quafity, quantity, and advantage, measured by density, proximity, and accessibility indices. County is the basic unit for analysis. The results reveal: (1) Transport dominance statistically follows a partial normal distribution. A very few counties, 1.4% of the total, have extremely high transport dominance which strongly supports the socio-economic development in these areas. In contrast, one eighth of all counties have poor transport dominance which impedes local socio-economic development to some extent. The remaining areas, about 70% of the counties, have median transport dominance. (2) Transport dominance is spatially unevenly distributed, with values decreasing gradually from the coastal area to the inland area. Areas in the first-highest level of transport dominance are mainly concentrated in the Yangtze River Delta, the Greater Beijing area, and the Pearl River Delta. Areas in the second-highest level are focused in Chengdu, Chongqing, and Wuhan metropolitan areas. Provincial capitals and a few other counties belong to the third-highest level. 展开更多
关键词 transport dominance DENSITY PROXIMITY ACCESSIBILITY China
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Species diversity, regeneration and dominance as influenced by canopy gaps and their characteristics in tropical evergreen forests of Western Ghats, India 被引量:10
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作者 Guddappa Mahalingappa Devagiri Anil Kumar Khaple +4 位作者 Siddagangaiah Mohan Puttanaik Venkateshamurthy Sanjay Tomar Arkalgud Nagaraja Arunkumar Geeta Joshi 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第4期799-810,共12页
Canopy gaps play a significant role in maintaining structure and composition of tropical forests. This study was carried out in tropical evergreen forests of central Western Ghats in India to understand the influence ... Canopy gaps play a significant role in maintaining structure and composition of tropical forests. This study was carried out in tropical evergreen forests of central Western Ghats in India to understand the influence of canopy gap size and the relationship of gap regime attributes to diversity measures and regeneration. The average gap size in the study area was found to be 396 m2 and around half of gaps were 4–8 years old. Gaps created by natural single tree fall were smaller in size but significantly higher in number. Diversity and regeneration of woody species were compared with canopy gaps and intact vegetation. Species richness and diversity was higher in gaps than in intact vegetation. Macaranga peltata, a shade intolerant species dominated gaps while intact vegetation was dominated by shade tolerant Kingiodendron pinnatum.Gap size significantly influenced species diversity and regeneration. Gap area and age were significantly and negatively correlated with diversity measures but positively correlated with regeneration. Among all the attributes of gaps, regeneration was significantly positively correlated with light intensity. Gaps maintained species diversity and favored regeneration of woody species. In addition to gap size and age, other gap ecological attributes also affected species diversity and regeneration. 展开更多
关键词 canopy forests regeneration dominance tropical woody vegetation intact Species dominated
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Economical effect of lumen apposing metal stents for treating benign foregut strictures 被引量:3
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作者 Alexander Hallac Wichit Srikureja +3 位作者 Eashen Liu Parag Dhumal Ashish Thatte Nishant Puri 《World Journal of Gastrointestinal Endoscopy》 CAS 2018年第10期294-300,共7页
AIM To evaluate the clinical and economical efficacy of lumen apposing metal stent(LAMS) in the treatment of benign foregut strictures.METHODS A single center retrospective database of patients who underwent endoscopi... AIM To evaluate the clinical and economical efficacy of lumen apposing metal stent(LAMS) in the treatment of benign foregut strictures.METHODS A single center retrospective database of patients who underwent endoscopic treatment of benign foregut strictures between January 2014 and May 2017 was analyzed. A control group of non-stented patients who underwent three endoscopic dilations was compared to patients who underwent LAMS placement. Statistical tests performed included independent t-tests and fiveparameter regression analysis RESULTS Nine hundred and ninety-eight foregut endoscopic dilations were performed between January 2014 and May 2017. 15 patients underwent endoscopic LAMS placement for treatment of benign foregut stricture. Thirty-six patients with recurrent benign foregut strictures underwent three or more endoscopic dilations without stent placement. The cost ratio of endoscopic dilation to LAMS(stent, placement and retrieval) is 5.77. Cost effective analysis demonstrated LAMS to be economical after three endoscopic dilation overall.LAMS was cost effective after two dilations in the Postsurgical stricture subgroup. CONCLUSION Endoscopists should consider LAMS for the treatment of benign foregut strictures if symptoms persist past three endoscopic dilations. Post-surgical strictures may benefit from LAMS if symptoms persist after two dilations in a post-surgical. Early intervention with LAMS appears to be a clinically and economically viable option for durable symptomatic relief in patients with these strictures. 展开更多
关键词 BENIGN ESOPHAGEAL STRICTURE Endoscopy ECONOMICS Stent ECONOMICS Self expandable metallic stents ESOPHAGEAL diseases
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Decadal variations in the community status of economically important invertebrates in the Bohai Sea 被引量:3
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作者 Qiang Wu Lisha Guan +2 位作者 Zhongyi Li Xiujuan Shan Xianshi Jin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第10期60-66,共7页
With the decline of fish stocks,the proportions of economically important invertebrates like crustaceans and cephalopods have increased in the Bohai Sea.The community structure and trophic level of economically import... With the decline of fish stocks,the proportions of economically important invertebrates like crustaceans and cephalopods have increased in the Bohai Sea.The community structure and trophic level of economically important invertebrates were analyzed using the bottom trawl survey data collected by the Yellow Sea Fisheries Research Institute in the Bohai Sea in May and August of 1958–1959,1982,1992–1993,2004,2009 and 2015.A total of 37 species of economically important invertebrates,belonging to 5 orders,24 families,were captured.The biomass densities of economically important invertebrates in the Bohai Sea displayed an overall downward trend from 1982 to 2015.Oratosquilla oratoria and Loligo spp.were the most dominant species in the past 30 years,the biomass proportion of O.oratoria increased gradually in both May and August from 1982 to 2015.Moreover,biodiversity indices of economically important invertebrates in the Bohai Sea appeared to decline from 1982 to 2004 and then increased in 2015.Similarly,the mean trophic level of economically important invertebrates declined from 1982 to 2004 and increased slightly in 2015.Overall,although the proportions of invertebrates have increased,the biomass densities in the Bohai Sea have displayed an overall downward trend from 1982 to 2015.The increases in the biodiversity and trophic level of economically important invertebrates after the 2000s,possibly benefit from stock enhancement projects implemented by governments at different levels and national fishery management measures such as the“double-control”of the total number and engine power of fishing vessels and summer moratorium of fishing. 展开更多
关键词 DECADAL VARIATIONS COMMUNITY structure TROPHIC level economically important invertebrates BohaiSea
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Ranking grey numbers based on dominance grey degrees 被引量:2
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作者 Yong Liu Jeffrey Forrest Naiming Xie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期618-626,共9页
With respect to the decision making problems where a lot of fuzzy and grey information always exists in the real-life decision making information system methods as fuzzy mathematics, it is difficult for such uncertain... With respect to the decision making problems where a lot of fuzzy and grey information always exists in the real-life decision making information system methods as fuzzy mathematics, it is difficult for such uncertainty probability, and interval numbers to deal with. To this end, based on the thought and method of grey numbers, grey degrees and interval numbers, the concept of dominance grey degree is defined. And then a method of ranking interval grey numbers based on the dominance grey degree is proposed. After discussing the relevant properties, the paper finally uses an example to demonstrate the effectiveness and applicability of the model. The result shows that the proposed model can more accurately describe uncertainty decision making problems, and realize the total ordering process for multiple-attribute decision-making problems. 展开更多
关键词 grey information dominance grey degree intervalgrey number total ordering.
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Changing trends in prevalence of different Plasmodium species with dominance of Plasmodium falciparum malaria infection in Aligarh(India) 被引量:1
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作者 Haris M Khan Fatima Shujatullah +1 位作者 Mohammad Ashfaq Adil Raza 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第1期64-66,共3页
Objective:To determine the prevalence of malaria in Aligarh and analyze species dominance in different years over a decade.Methods:Diagnosis of malaria was done using microscopy as gold standard,rapid antigen detectio... Objective:To determine the prevalence of malaria in Aligarh and analyze species dominance in different years over a decade.Methods:Diagnosis of malaria was done using microscopy as gold standard,rapid antigen detection assays and quantitative buffy coat(QBC) assays.Giemsa stained blood smear examination was done,thick and thin films were examined for presence of different Plasmodium spp.Rapid antigen detection assays employing detection of HRP-2 and parasite lactate dehydrogenase antigen(pLDH) by immunochromatography was done in patients whose blood smear found to be negative by conventional Giemsa slide examination.QBC was done in cases where there is strong clinical suspicion of malaria with blood smear negative,in patients with chronic malaria,splenomegaly,or in those patients who had inadequate treatment and for post-treatment follow up.Results:Plasmodium vivax and Plasmodium falciparum were only species detected in our hospital.Overall prevalence of malaria in Aligarh was found to be 8.8%.The maximum prevalence of 20.1%was observed in year 2008 and lowest 2.3%in 2002. Conclusions:High prevalence of malaria is observed in this part of country with dominance of both species particularly Plasmodium falciparum should be monitored and factors accounting for occurrence should be studied to employ effective control measures. 展开更多
关键词 PLASMODIUM FALCIPARUM PREVALENCE dominance MALARIA
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Robust sliding mode control for fractional-order chaotic economical system with parameter uncertainty and external disturbance 被引量:3
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作者 周柯 王智慧 +2 位作者 高立克 孙跃 马铁东 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第3期101-106,共6页
This paper presents a modified sliding mode control for fractional-order chaotic economical systems with parameter uncertainty and external disturbance. By constructing the suitable sliding mode surface with fractiona... This paper presents a modified sliding mode control for fractional-order chaotic economical systems with parameter uncertainty and external disturbance. By constructing the suitable sliding mode surface with fractional-order integral, the effective sliding mode controller is designed to realize the asymptotical stability of fractional-order chaotic economical systems. Comparing with the existing results, the main results in this paper are more practical and rigorous. Simulation results show the effectiveness and feasibility of the proposed sliding mode control method. 展开更多
关键词 fractional-order chaotic systems economical system sliding mode control parameter uncertainty
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Comparison of Economical and Technical Indices on Rare Earth Separation Processes of Bastnasite by Solvent Extraction 被引量:2
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作者 严纯华 廖春生 +2 位作者 贾江涛 王明文 李标国 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第1期59-64,共6页
According to the composition of rare earth ores and the market, several feasible separation processes of bastnasite in Baotou of Inner Mongolia and Mianning of Sichuan by solvent extraction in HEH(EHP) HCl system wer... According to the composition of rare earth ores and the market, several feasible separation processes of bastnasite in Baotou of Inner Mongolia and Mianning of Sichuan by solvent extraction in HEH(EHP) HCl system were presented. The parameters of the processes such as stage numbers, volume of mixer settler, fixed investment of extractant and rare earths, consumption of chemical reagents including HCl and NH 3 were calculated and compared. The results show that the novel scheme can save cost more than 20% compared with those of others. By the economical analysis, the optimized separation process of bastnasite was obtained, which can be applied to the treatment of monazite too. 展开更多
关键词 Rare earths Bastnasite Solvent extraction economical index Technical index
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Evaluation of the Economical and Intensive Use of Industrial Land in Chizhou Economic and Technological Development Zone 被引量:3
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作者 Rui LIU 《Asian Agricultural Research》 2014年第10期85-90,共6页
Based on the subdivision of industrial land in Chizhou Economic and Technological Development Zone,this paper builds the evaluation indicator system for the economical and intensive use of industrial land in the devel... Based on the subdivision of industrial land in Chizhou Economic and Technological Development Zone,this paper builds the evaluation indicator system for the economical and intensive use of industrial land in the development zone,to analyze the current situation of economical and intensive use of industrial land. The results show that the levels of economical and intensive use of industrial land vary in the development zone; the factors affecting the intensive degree of various industries also vary; the industry in Chizhou Economic and Technological Development Zone is still in the transition phase from inefficient use to low level of use to intensive use. 展开更多
关键词 INDUSTRIAL LAND economical and INTENSIVE use Evalu
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The Analysis of Dominance Degree of Land Use in Irrigation District——A Case Study of Jinghuiqu Irrigation District in Shaanxi Province 被引量:1
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作者 ZHOU Lu-hong1, LI Ya-ni2, WANG Xiao-feng1 1. College of Earth Science and Land Resources, Chang’an University, Xi’an 710054, China 2. Tourism & Hotel Management Department, Shunde Polytechnic, Shunde 528333, China 《Asian Agricultural Research》 2012年第1期54-57,共4页
According to the remote sensing interpretation data in study area, statistics and the data concerning agricultural land classification of Shaanxi Province, on the basis of degree of dominance of land use, taking Jingh... According to the remote sensing interpretation data in study area, statistics and the data concerning agricultural land classification of Shaanxi Province, on the basis of degree of dominance of land use, taking Jinghuiqu Irrigation District as an example, this paper adopts benefit-cost analysis method and the method of degree of dominance of land resources per capita to conduct analysis on degree of dominance of land. The results show that in study area, the ratio of cost and benefit of farmland is 1.5, with relative big value, indicating that farmland is the dominant land resource in Jinghuiqu Irrigation District; the abundance of land resources in study area is 0.73, the combination index of land resources is 2.3, and degree of dominance of land resources per capita is 0.32, indicating that the combination index of land resources in study area is relatively big, while degree of dominance of land resources per capita is relatively small, which shows that in study area, the combination of all kinds of land resources is in a poor state, with poor supporting ability. In view of the status quo that the combination of all kinds of land resources is in a poor state, with poor supporting ability in Jinghuiqu Irrigation District, the corresponding policy suggestions are put forward as follows: first, strictly implement the central policy and protect farmland resources; second, adjust land use structure and strive to promote benefit; third, make rational planning of land resources and take the road of sustainable development; fourth, take the irrigation district as the unit and establish use class and price standard of land in irrigation district. 展开更多
关键词 dominance DEGREE of LAND RESOURCES Benefit-cost DE
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Dominance hierarchy and social relationships in a group of Captive black-and-white snub-nosed monkeys (Rhinopithecus bietl) 被引量:2
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作者 Liang-Wei CUI Qing-Lei SUN Bao-Guo LI 《Zoological Research》 CAS CSCD 北大核心 2014年第3期204-213,共10页
Different types of dominance hierarchies reflect different social relationships in primates. In this study, we clarified the hierarchy and social relationships in a one-male unit of captive Rhinopithecus bieti observe... Different types of dominance hierarchies reflect different social relationships in primates. In this study, we clarified the hierarchy and social relationships in a one-male unit of captive Rhinopithecus bieti observed between August 1998 and March 1999. Mean frequency of agonistic behaviour among adult females was 0.13 interactions per hour. Adult females exhibited a linear hierarchy with a reversal of 10.9%, indicating an unstable relationship; therefore, R. bieti appears to be a relaxed/tolerant species. The lack of a relationship between the agonistic ratio of the adult male towards adult females and their ranks indicated that males did not show increased aggression towards low-ranking females. Differentiated female affiliative relationships were loosely formed in terms of the male, and to some extent influenced by female estrus, implying that relationships between the male and females is influenced by estrus and not rank alone. A positive correlation between the agonistic ratio of adult females and their ranks showed that the degree to which one female negatively impacted others decreased with reduction in rank. Similarly, a positive correlation between the agonistic ratio of females and differences in rank suggests that a female had fewer negative effects on closely ranked individuals than distantly ranked ones. These data indicate that rank may influence relationships between females. A steeper slope of regression between the agonistic ratio and inter-female rank differences indicated that the extent of the power difference in high-ranking females exerting negative effects on low-ranking ones was larger during the mating season than the birth season, suggesting that rank may influence the mating success of females. 展开更多
关键词 dominance style Hierarchy LINEARITY Rhinopithecus bieti Social relationship
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