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Order of Precedence Between Local Laws of Cities with Subordinate Districts and Regulations of Provincial Governments Clarifying Premises for Discussion Based on the Characteristics of Laws
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作者 Zheng Tai'an Lin Min Zhang Congrong 《Contemporary Social Sciences》 2018年第2期106-117,共12页
The lack of descriptions regarding the order of precedence between the local laws of cities with subordinate districts and the regulations of provincial governments in Legislation Law of the People's Republic of C... The lack of descriptions regarding the order of precedence between the local laws of cities with subordinate districts and the regulations of provincial governments in Legislation Law of the People's Republic of China(Legislation Law) has led to two divergent views. One holds that "the local laws of cities with subordinate districts should take precedence over the regulations of provincial governments," while the other supports the exact opposite. This is a value judgment issue in legislation. To reach a solution, we need to clarify the premises based on the characteristics of the laws in question so that a basic common ground can be established for discussion. The first premise for traditional legislation is that a law should be based on experience as well as logic; the second is that the experience of authority subjects, plus the three aspects of logic should outweigh the experience of social subjects, plus the three aspects of logic. With respect to postmodern legislation, the first premise is that experience should override logic, and the second is that the experience of the authority subject should take precedence over that of social subject, with no requirements for logical consistency. Since Legislation Law fal s into the category of postmodern legislation, according to the premises, the argument that the local laws of cities with subordinate districts should take precedence enjoys wider acceptance, but the view is logically challenged in terms of conceptual consistency, system consistency and principle consistency. More studies must be conducted to facilitate the discussion. 展开更多
关键词 cities with subordinate districts local laws regulations of provincial governments order of precedence premises postmodern legislation
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Improvement of Urban Rail Transit Laws and Regulations System in China
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作者 LI Jian 《International English Education Research》 2016年第2期14-16,共3页
Legal management is the fundamental guarantee of urban rail transit management's benign operation; and the comprehensive legal management of urban rail transit is also the important development trend of urban rail tr... Legal management is the fundamental guarantee of urban rail transit management's benign operation; and the comprehensive legal management of urban rail transit is also the important development trend of urban rail transit in the world. This article aims to analyze the problems existing in China's urban rail transit legal management, to improve the corresponding laws and regulations system, and to put forward some suggestions on how to optimize the urban rail transit legal management. 展开更多
关键词 Urban Rail Transit Legal Management laws and regulations system
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The Current Conservation Efforts and Future Prospects for the Endangered Nubian Ibex (Capra nubiana ibex) in Sudan
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作者 Lubna Mohammed Abdallah Hassan Mutasim Essa Abdallah Adam +1 位作者 Latifa Altigani Adam Abakar Nasir Yousif Gaboush Brema 《Journal of Environmental Protection》 2024年第1期39-62,共24页
A comprehensive action plan for the conservation of the endangered species, the Nubian ibex in Sudan, can be developed by gaining a thorough understanding of their current status, conservation strategy, and relevant l... A comprehensive action plan for the conservation of the endangered species, the Nubian ibex in Sudan, can be developed by gaining a thorough understanding of their current status, conservation strategy, and relevant laws and regulations, as well as raising awareness about the importance of protecting endangered species. The Nubian ibex is listed as an endangered species on The International Union for Conservation of Nature (IUCN) Red List, highlighting the need for further research on population conservation efforts due to insufficient population data. To address this knowledge gap, a questionnaire was conducted with various stakeholders, including police officers, researchers, and lecturers, representing a diverse range of organizations and universities. The findings revealed that hunting is the primary factor contributing to endangerment. Mammals account for 80% of endangered species, while reptiles comprise less than one-tenth. Research centers are recognized as the main governing body, and 85% of participants are concerned about the declining population. Hunting accounted for less than half of the threats to the ibex population in Sudan, while habitat loss made up a quarter. Mining, climate change, human activity, and agriculture were also identified as risks. However, there were no plans, strategies, procedures, or measures in place to conserve the Nubian ibex. There were also no initiatives to preserve its biodiversity, and awareness about endangered species was lacking. Although participants believed that laws were effective in protecting the ibex, no licenses were issued for its conservation, and annual surveys were not conducted. Additionally, there were no recorded instances of Mukhalfat related to the Nubian ibex. In light of these findings, we propose various conservation measures to address these challenges. These measures include the implementation of laws and regulations, conducting annual surveys to monitor population trends, protecting habitats, establishing breeding and releasing programs, launching awareness campaigns, undertaking rehabilitation efforts, enhancing research efforts, and developing comprehensive conservation strategies. Additionally, it is crucial to foster cooperation among wildlife institutes to ensure the effective implementation of these conservation measures. 展开更多
关键词 Nubian Ibex SUDAN Endangered Species Conservation Status Law regulations AWARENESS
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Implications of Declining Ground Water and Water Quality in the US Southeastern Coastal Plain Ecoregion and Areawide Environmental Impact Statement Required for Mining in the Greater Okefenokee Swamp Basin—Part 1
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作者 Sydney T. Bacchus Sergio Bernardes Marguerite Madden 《Journal of Geoscience and Environment Protection》 2023年第3期201-276,共76页
Karst aquifers occur worldwide and exhibit groundwater flow responses that differ considerably from aquifers lacking fractures, bedding planes, and other karst conduits where significant and rapid groundwater flow can... Karst aquifers occur worldwide and exhibit groundwater flow responses that differ considerably from aquifers lacking fractures, bedding planes, and other karst conduits where significant and rapid groundwater flow can occur. The regional, karst Floridan aquifer system underlies the United States (US) Southeastern Coastal Plain Physiographic Region and exhibits hydrologic interconnections with overlying surficial aquifers and throughout other zones of the aquifer system, as is characteristic of other karst aquifer systems. Anthropogenic groundwater declines in this regional karst aquifer system have been documented in published literature for decades, but the impacts of those declines in this coastal plain region and the embedded ecosystems that provide essential and critical habitat for native, endemic, and federally endangered and threatened species have not been considered previously. Those anthropogenic groundwater declines reduce surfacewater levels and flows due to the capture of both groundwater and overland flow of surfacewater, resulting in induced recharge through semi-confining zones and interbasin flow through fractures and other karst conduits. This case study identifies examples from the Greater Okefenokee Swamp Basin study area and comparison areas of how those declines result in loss of historic base flow to surface waters and other capture of surface waters, ultimately increasing saltwater intrusion. Those results alter and degrade the physical, chemical, and biological integrity of the nation’s waters, in violation of the US Clean Water Act (CWA) of 1972. Historic groundwater declines from mining and other anthropogenic groundwater withdrawals from this regional karst aquifer system already threaten the survival and recovery of federally endangered and threatened species, as well as existing and proposed critical habitat for those species within this regional extent, in violation of the Endangered Species Act (ESA) of 1973. This case study and its companion publication (Part 2) appear to be the first to provide scientific support for this regional karst aquifer system as the unifying factor in habitat responses to irreversible groundwater impacts on aquatic and marine ecosystems. These adverse impacts strongly suggest that the extent of the regional Floridan aquifer system should be designated as the Southeastern Coastal Plain Ecoregion for the purpose of managing natural resources. Mining activities continue to expand in our study area, which is the Greater Okefenokee Swamp Basin. Despite that fact, no comprehensive Areawide Environmental Impact Statement (AEIS), similar to the AEIS required for phosphate mining within the Central Florida Phosphate District (CFPD) approximately a decade ago has been conducted for any of the numerous mining projects that are occurring and are proposed within the Greater Okefenokee Swamp Basin. This case study also provides examples of why a comprehensive AEIS is essential to consider all of the adverse direct, indirect, and cumulative impacts of those mining activities to the CWA, the ESA, and the irreversible losses to local economies, because federal agencies responsible for considering those adverse impacts rely on public comments to identify those adverse impacts. The mining activities authorized throughout the regional Floridan aquifer system under Category 44 Nationwide Permits (NWP) result in the same type of adverse impacts as the mining activities evaluated under Individual Permits in that region. Therefore, those Category 44 NWP mining activities also should be required to obtain Individual Permits and be evaluated under an AEIS in the Greater Okefenokee Swamp Basin. This case study also describes how Florida’s assumption of the CWA Section 404 regulatory authority in 2020 severs four sub-basins within the Greater Okefenokee Swamp Basin study area at the state line between Florida and Georgia. 展开更多
关键词 1994 Government Accountability Report for Ecosystem Management Abuse of Economics Environmental laws and regulations Okefenokee National Wildlife Refuge Resource Sustainability
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Discussion on Kazakhstan's Construction Laws from the Perspective of the Belt and Road Initiative
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作者 Li Shan 《Contemporary Social Sciences》 2019年第1期65-70,共6页
This article introduces the present situations of Chinese enterprises engaged in construction in Kazakhstan under the Belt and Road Initiative,analyzes the three main legal issues faced by Chinese enterprisesc and the... This article introduces the present situations of Chinese enterprises engaged in construction in Kazakhstan under the Belt and Road Initiative,analyzes the three main legal issues faced by Chinese enterprisesc and the related laws and regulations in Kazakhstan,and finially provides some legal advice forChinese companies. 展开更多
关键词 the BELT and ROAD INITIATIVE construction laws and regulations ADVICE
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Traditional Chinese Medicine in Malaysia: A Brief Historical Overview of Laws and Regulations
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作者 Hon Foong Wong Shih Chau Ng +6 位作者 Wen Tien Tan Huiying Wang Xun Lin Si Woei Goh Bao Ling Hoo Chyong En Chai Jun Liu 《Chinese Medicine and Culture》 2019年第4期162-165,共4页
Although traditional Chinese medicine(TCM)has been a part of the Malaya and the Malaysia people’s method of maintaining health and well-being for many centuries,it was never been enrolled in the public health-care sy... Although traditional Chinese medicine(TCM)has been a part of the Malaya and the Malaysia people’s method of maintaining health and well-being for many centuries,it was never been enrolled in the public health-care system.However,the rising cost of Western drugs and the increasing number of people frequenting TCM has driven the government to search for cheaper options and to look into its safe practice.In 1992,the government mandated all TCM herbal products to be registered with the National Pharmaceutical Control Bureau.All TCM products sold in Malaysia are now Good Manufacturing Practice certified.The government has also established a Traditional and Complementary Medicine Division within the Ministry of Health.Between 2008 and 2014,a traditional and complementary medicine unit was set up in major hospitals in all states.TCM is one of the main services offered by the unit.In 2016,the government enacted the Traditional and Complementary Medicine Act to regulate the TCM practice.Subsequently,a 10-vear blueprint has been drawn to support the development of all traditional and complementary medicines in Malaysia.This article aims to provide a brief overview on the regulatory development of TCM in Malaysia. 展开更多
关键词 Development of traditional Chinese medicine historical overview laws and regulations MALAYSIA Traditional Chinese medicine
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Analysis of Laws and Regulations on Vaccine Quality Control in China
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作者 Zhi Yuanyuan Wang Shuling He Yalan 《Asian Journal of Social Pharmacy》 2019年第3期92-99,共8页
Objective To analyze laws, regulations and the responsibilities of relevant authorities for vaccine quality control and to provide suggestions for improving vaccine quality control system in China. Methods Laws and ru... Objective To analyze laws, regulations and the responsibilities of relevant authorities for vaccine quality control and to provide suggestions for improving vaccine quality control system in China. Methods Laws and rules issued by related authorities were classified and studied. Results and Conclusion There are still some problems in the basic laws and regulations, including the lack of legal basis, the unclear responsibilities of relevant authorities and so on. We should improve the current laws, regulations as well as the responsibilities of the authorities so as to build up a sound system of vaccine traceability gradually. 展开更多
关键词 VACCINE QUALITY control LAW and REGULATION RELEVANT AUTHORITY
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International Comparative Study on Education Laws of the Persons with Disabilities: An Observation on Regulations on the Education of Persons with Disabilities
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作者 黄伟 ZHANG Wenhong 《The Journal of Human Rights》 2017年第4期327-335,共9页
The issue of education for people with disabilities has become of increasing concern. How can we effectively guarantee the basic right to education for persons with disabilities? Will the revised Regulation on Educati... The issue of education for people with disabilities has become of increasing concern. How can we effectively guarantee the basic right to education for persons with disabilities? Will the revised Regulation on Education for Persons with Disabilities meet their needs? This article takes the Regulation on Education for Persons with Disabilities as the core and compares it with the related special educational laws of the United States, Britain and Japan. The following conclusions were drawn from this study: In terms of educational concept, the three countries follow the concept of inclusive education, and pursue equity and educational justice. They not only pay attention to inclusive education but also focus on improving the quality of education for students with disabilities. All three countries focus on accommodating children with special needs, but each implements its programs in a different way. These practices can be used as reference for the development of a special needs education law in China. 展开更多
关键词 children with disabilities right to education regulation on the education of persons with disabilities international law special needs
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The Latest Status and Progress of Domestic and Foreign Regulations on Cosmetic Efficacy Claims
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作者 Li Yanan Jiang Ligang 《China Detergent & Cosmetics》 2021年第3期46-53,共8页
The supervision and administration of cosmetics and its two supporting documents related to efficacy,cosmetics classification rules and classification catalogue and evaluation standard of cosmetic efficacy claims,have... The supervision and administration of cosmetics and its two supporting documents related to efficacy,cosmetics classification rules and classification catalogue and evaluation standard of cosmetic efficacy claims,have been successively introduced and implemented,making China’s cosmetics industry officially enter the era of efficacy evaluation.In the time window when the new era is coming,the definitions of cosmetics in China and other countries are compared.The latest status and progress of regulations on cosmetic efficacy claims in China and other countries are summarized,and the standard methods or guidance of cosmetic efficacy evaluation at home and abroad are introduced.The enlightenment from the supervision systems of cosmetic efficacy in other cosmetic consumer markets around the world are discussed.In addition,the opportunities and challenges for cosmetic enterprises under the background of cosmetic law reform in China are also prospected. 展开更多
关键词 COSMETICS efficacy claims laws and regulations China Europe and America standard methods evaluation guidelines
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Food safety regulatory systems in Europe and China:A study of how co-regulation can improve regulatory effectiveness 被引量:17
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作者 Kevin Chen WANG Xin-xin SONG Hai-ying 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第11期2203-2217,共15页
Food safety has received a great deal of attention in both developed and developing countries in recent years. In China, the numerous food scandals and scares that have struck over the past decade have spurred signifi... Food safety has received a great deal of attention in both developed and developing countries in recent years. In China, the numerous food scandals and scares that have struck over the past decade have spurred significant food safety regulatory reform, which has been increasingly oriented towards the public-private partnership model adopted by the Europe Union's (EU) food safety regulatory system. This paper analyzes the development of both the EU's and China's food safety regu- latory systems, identifies the current challenges for China and additionally considers the role of public-private partnership. The success of co-regulation in the food regulatory system would bring significant benefits and opportunities for China. Finally, this paper recommends additional measures like training and grants to improve the private's sector effectiveness in co-regulating China's food safety issues. 展开更多
关键词 food safety co-regulation public-private partnership Food Safety Law of China European Union China
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The Relationship between Civil&Commercial Law and Economic Law in the Context of the Market Economy
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作者 Ding Yanshen Fu Qilin 《学术界》 CSSCI 北大核心 2020年第7期218-226,共9页
Both civil&commercial law and economic law are the main legal basis for supervising market behavior and regulating market order.They are indispensable laws in the national economic development and construction.By ... Both civil&commercial law and economic law are the main legal basis for supervising market behavior and regulating market order.They are indispensable laws in the national economic development and construction.By analyzing the relationship between civil&commercial law and economic law in the context of market economy,this article explores the similarities and differences between,and through the perfection and application of the two,China’s social and economic stability and a lasting progress can be better realized under the mechanism of market economy. 展开更多
关键词 market economy civil&commercial law(CCL) economic law economic regulation
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Use of Augmented Reality Methods to Support Legal Conflicts in the Planning Process for Wind Turbines Using the Example of the Landscape Conservation Area “Eulenkopf and Surroundings”
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作者 Timo Wundsam Sascha M. Henninger 《Energy and Power Engineering》 2014年第11期349-361,共13页
The world’s growing energy demand poses a serious problem. At the same time fossil fuels are finite, which we must work against. Therefore, the Federal Government of Germany has set itself the goal to push forward th... The world’s growing energy demand poses a serious problem. At the same time fossil fuels are finite, which we must work against. Therefore, the Federal Government of Germany has set itself the goal to push forward the use of renewable energy in order to completely do without the generation of nuclear energy by 2023. There are, however, no specific guidelines from the European Directive on the promotion of electricity from renewable energy sources for the internal electricity market regarding how high each share of the different production method should be and, above all, which specific aim should be achieved by the share of wind energy. Nevertheless, it presents a crucial step toward a nuclear phaseout and a concomitant change of course of the Federal Government of Germany in the spring of 2011 regarding the expansion of renewable energy, taking the nuclear catastrophe in Fukushima into account. Using new legal planning approaches, also including the area of Rhineland-Palatinate, opportunities should be provided to make previously protected land available for setting up facilities for the generation of renewable energy. However, it is important to examine the legal situation regarding the installation of these kinds of constructions more detailed, as no general statements can be made. This will be illustrated using the example of the landscape conservation area “Eulenkopf and surrounding area” in the district of Kaiserslautern. The stated goal of the Social Democrat/Green coalition of the federal state government of Rhineland-Palatinate is to considerably expand the generation of electricity from renewable energy sources so that by 2030 at least the entire electricity demand can be covered by those. Due to the enormous potential of wind power, it is therefore necessary to quintuple its share of electricity generation by 2020, compared to 2011 numbers. In order to achieve the desired political objectives, by 2030 the number of turbines has to be increased to around 2650, representing a capacity of 7500 MW. This increase gives reason for boundary conditions to manage the generation of wind energy to be adjusted. This is intended to facilitate management and simultaneously minimise negative effects, such as the “sprawling” of wind turbines. 展开更多
关键词 RENEWABLE ENERGY Wind ENERGY Turbines Urban Planning Landscape Conservation Area Regulation laws AUGMENTED Reality Public INTEREST
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Stakeholders’ Compliance with Existing Construction Health and Safety Related Laws and Regulations in Ghana
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作者 Dickson Osei-Asibey Joshua Ayarkwa +2 位作者 Alex Acheampong Emmanuel Adinyira Peter Amoah 《Journal of Building Construction and Planning Research》 2021年第2期138-159,共22页
This paper explored stakeholders’ compliance with existing laws and regulations related to construction health and safety (CHS) in the Ghanaian construction industry (GCI). Qualitative research approach was adopted f... This paper explored stakeholders’ compliance with existing laws and regulations related to construction health and safety (CHS) in the Ghanaian construction industry (GCI). Qualitative research approach was adopted for the data collection, using semi-structured interview guide. An in-depth face-to-face interview based on the grounded theory approach was conducted with actors who play important roles in ensuring health and safety at the construction site as well as key officers and professionals who are the major stakeholders in the GCI. Content analysis was adopted for the analysis of the qualitative data. The findings of the study show customary laws, bye laws, Labour Act, 2003 (Act 651), Local Governance Act, 2016 (Act 936) and the contract document as the key existing CHS related laws and regulations that the stakeholders comply with. The stakeholders also identified the following construction health and safety related regulations in the GCI which have low compliance rate: Factories, Shops and Offices Act, 1974 (Act 323), Environmental Protection Act, 1994 (Act 490), among others. The findings of the research contribute to knowledge of stakeholders’ compliance with existing laws and regulations related to CHS, and underscore the need to ensure monitoring and enforce compliance in the GCI. The findings further identify areas for stakeholders to focus attention on ensuring good health and safety practices, and also expose critical training and education needs for stakeholders in the GCI. The findings provide valuable insights on stakeholders’ compliance with laws and regulations related to CHS in Ghana, which may be applicable to other developing countries with similar construction industry. 展开更多
关键词 laws regulations COMPLIANCE Construction Health and Safety Ghana STAKEHOLDERS
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Regulation Law of Turbine and Generator in Organic Rankine Cycle Power Generation Experimental System
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作者 潘利生 王怀信 史维秀 《Transactions of Tianjin University》 EI CAS 2014年第4期237-242,共6页
In the performance experiment of organic Rankine cycle power generation experimental system, the loadresistance-regulation method is one of the most important regulation methods. However, the regulation law has not be... In the performance experiment of organic Rankine cycle power generation experimental system, the loadresistance-regulation method is one of the most important regulation methods. However, the regulation law has not been clear enough to guide the experiment, which is unfavorable to the experimental research on organic Rankine cycle. In this paper the regulation law of turbine and generator by the load-resistance-regulation method is studied theoretically and experimentally. The results show that when the thermal cycle parameters keep constant, the turbine speed increases with the increase of load resistance and there is a maximum value of transmission-generator efficiency with the variation of the turbine speed; when the turbine speed and generator speed keep constant, the transmissiongenerator efficiency decreases and gradually tends to zero with the increase of load resistance. 展开更多
关键词 organic Rankine cycle (ORC) regulation law load-resistance-regulation method
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Research on the Policies and Means Changes of Macro Regulation and Control of Chinese and Foreign Governments
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作者 Chengrong Cai 《Journal of Finance Research》 2017年第1期5-8,共4页
In the process of economic development, government uses the "visible hand" to achieve macroeconomic regulation and control for "market failure", which has been common knowledge among people after W... In the process of economic development, government uses the "visible hand" to achieve macroeconomic regulation and control for "market failure", which has been common knowledge among people after World War II. Comparing policy and means adopted by Chinese and foreign governments in macro regulation and control, we can see that the choice is different in different historical periods and the change of emphasis in macro regulation and control policy and means has the convergence tendency. We can make the following conclusion from research of the change rules of macro regulation and control means in the market economic condition of Chinese and foreign governments: supply-side structural reform in China complies with the basic rules of development of market economy. 展开更多
关键词 MACROECONOMIC regulation and control Policy MEANS laws of ECONOMICS
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Call for an Institution with the Authority and Mandate with Regard to Technical Disputes and Fundamental Consideration for the System
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作者 Nico P. M. Scholten Mathilde I. Houben 《Journal of Civil Engineering and Architecture》 2015年第5期563-572,共10页
Based on this evidence and many other examples, this paper advocates a drastic overhaul of the system, in which a distinction is made between simple, standard projects, less simple solutions that can be assessed with ... Based on this evidence and many other examples, this paper advocates a drastic overhaul of the system, in which a distinction is made between simple, standard projects, less simple solutions that can be assessed with performance requirements, and high-value projects which are handled in accordance with the science of probabilistics. Next to or in addition to the Council of State, there has to be a technical body appointed under statute with non-departmental public body status, which can issue binding rulings in technical disputes, with very short procedural delays. 展开更多
关键词 Building regulation and control construction law conflict resolution.
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The Animal Health Law-Regulation EU 2016/429 and the Future of Food Safety and Free Commerce in Europe
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作者 Giancarlo Ruffo Valentina Locatelli +1 位作者 Francesco Maraschi Paola Fossati 《Journal of Food Science and Engineering》 2018年第2期61-64,共4页
The aim of this study was to analyze the contents of Reg.(EU)No.429/2016,and to assess its role in guaranteeing the efficient application of the disease prevention and control rules into member state.Furthermore,the a... The aim of this study was to analyze the contents of Reg.(EU)No.429/2016,and to assess its role in guaranteeing the efficient application of the disease prevention and control rules into member state.Furthermore,the authors evaluated the impact of the abovementioned Regulation on the legislation on public health and food safety already in force in Europe(Regulations EC No.178/2002,No.882/2004,No.853/2004)and considered the global impact of the new rules on the effective functioning of the internal market.The study pays attention also to the TFEU(treaty of lisbon on the functioning of the European union)procedure to delegate to the commission the power to adopt non-legislative acts of general application that supplement or amend certain non-essential elements of a legislative act. 展开更多
关键词 ANIMAL HEALTH law food safety VETERINARY ofFICIAL controls EU Regulation public HEALTH transmissible ANIMAL diseases disease NOTIFICATION
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About One Discrete Mathematical Model of Perfect Fluid
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作者 Konstantin Eduardovich Plokhotnikov 《Open Journal of Modelling and Simulation》 2016年第3期129-167,共40页
In work, it is constructed a discrete mathematical model of motion of a perfect fluid. The fluid is represented as an ensemble of identical so-called liquid particles, which are in the form of extended geometrical obj... In work, it is constructed a discrete mathematical model of motion of a perfect fluid. The fluid is represented as an ensemble of identical so-called liquid particles, which are in the form of extended geometrical objects: circles and spheres for two-dimensional and three-dimensional cases, respectively. The mechanism of interaction between the liquid particles on a binary level and on the level of the n-cluster is formulated. This mechanism has previously been found by the author as part of the mathematical modeling of turbulent fluid motion. In the turbulence model was derived and investigated the potential interaction of pairs of liquid particles, which contained a singularity of the branch point. Exactly, this is possible to build in this article discrete stochastic-deterministic model of an ideal fluid. The results of computational experiment to simulate various kinds of flows in two-dimensional and three-dimensional ensembles of liquid particles are presented. Modeling was carried out in the areas of quadratic or cubic form. On boundary of a region satisfies the condition of elastic reflection liquid particles. The flows with spontaneous separation of particles in a region, various kinds of eddy streams, with the quite unexpected statistical properties of an ensemble of particles characteristic for the Fermi-Pasta-Ulam effect were found. We build and study the flow in which the velocity of the particles is calibrated. It was possible using the appropriate flows of liquid particles of the ensemble to demonstrate the possibility to reproduce any prescribed image by manipulating the parameters of the interaction. Calculations of the flows were performed with using MATLAB software package according to the algorithms presented in this article. 展开更多
关键词 perfect Fluid Discrete Model Liquid Particle Branch Point TURBULENCE Interaction in the Cluster the laws of Conservation Stochastic and Deterministic Components of the Flow Computational Experiment the Separation of Particles the Effect of the Fermi-Pasta-Ulam Calibration of Particle Velocities
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Metamaterial terahertz device with temperature regulation function that can achieve perfect absorption and complete reflection conversion of ultrawideband
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作者 Hao Sun Zao Yi +4 位作者 Can Ma Shubo Cheng Bin Tang Qingdong Zeng Sohail Ahmad 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第7期123-133,共11页
The field of terahertz devices is important in terahertz technology.However,most of the current devices have limited functionality and poor performance.To improve device performance and achieve multifunctionality,we d... The field of terahertz devices is important in terahertz technology.However,most of the current devices have limited functionality and poor performance.To improve device performance and achieve multifunctionality,we designed a terahertz device based on a combination of VO_(2)and metamaterials.This device can be tuned using the phase-transition characteristics of VO_(2),which is included in the triple-layer structure of the device,along with SiO_(2)and Au.The terahertz device exhibits various advantageous features,including broadband coverage,high absorption capability,dynamic tunability,simple structural design,polarization insensitivity,and incidentangle insensitivity.The simulation results showed that by controlling the temperature,the terahertz device achieved a thermal modulation range of spectral absorption from 0 to 0.99.At 313 K,the device exhibited complete reflection of terahertz waves.As the temperature increased,the absorption rate also increased.When the temperature reached 353 K,the device absorption rate exceeded 97.7%in the range of 5-8.55 THz.This study used the effective medium theory to elucidate the correlation between conductivity and temperature during the phase transition of VO_(2).Simultaneously,the variation in device performance was further elucidated by analyzing and depicting the intensity distribution of the electric field on the device surface at different temperatures.Furthermore,the impact of various structural parameters on device performance was examined,offering valuable insights and suggestions for selecting suitable parameter values in real-world applications.These characteristics render the device highly promising for applications in stealth technology,energy harvesting,modulation,and other related fields,thus showcasing its significant potential. 展开更多
关键词 terahertz perfect absorption complete reflection temperature regulation ULTRAWIDEBand smart device
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Optimization of the co-closing law of guide vanes and blades for bulb turbines based on CFD
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作者 Hui Liu Yun-fa Lin +4 位作者 Yong-guang Cheng Song Xue Mao-jia Tang Jian Zhang Jia-yi Fan 《Journal of Hydrodynamics》 SCIE EI CSCD 2024年第2期363-377,共15页
The load rejection transient process of bulb turbine units is critical to safety of hydropower stations,and determining appropriate closing laws of guide vanes(GVs)and runner blades(RBs)for this process is of signific... The load rejection transient process of bulb turbine units is critical to safety of hydropower stations,and determining appropriate closing laws of guide vanes(GVs)and runner blades(RBs)for this process is of significance.In this study,we proposed a procedure to optimize the co-closing law of GVs and RBs by using computational fluid dynamics(CFD),combined with the design of experiment(DOE)method,approximation model,and genetic optimization algorithm.The sensitivity of closing law parameters on the histories of head,speed,and thrust was analyzed,and a two-stage GVs’closing law associating with a linear RBs’closing law was proposed.The results show that GVs dominate the transient characteristics by controlling the change of discharge.Speeding GVs’first-stage closing speed while shortening first-stage closing time can not only significantly reduce the maximum rotational speed but also suppress the water hammer pressure;slowing GVs’second-stage closing speed is conducive to controlling the maximum reverse axial force.RBs directly affect the runner force.Slowing RBs’closing speed can further reduce the rotational speed and the maximum reverse axial force.The safety margin of each control parameter,flow patterns,and pressure pulsations of a practical hydropower station were all improved after optimization,demonstrating the effectiveness of this method. 展开更多
关键词 Bulb turbine load rejection transient process double regulation closing law OPTIMIZATION computational fluid dynamics(CFD)
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