期刊文献+
共找到4,797篇文章
< 1 2 240 >
每页显示 20 50 100
United States Healthcare Data Breaches: Insights for NIST SP 800-66 Revision 2 from a Review of the NIST SP 800-66 Revision 1
1
作者 Mohammed Mohammed Raoof 《Journal of Information Security》 2024年第2期232-244,共13页
Healthcare security and privacy breaches are occurring in the United States (US), and increased substantially during the pandemic. This paper reviews the National Institute of Standards and Technology (NIST) publicati... Healthcare security and privacy breaches are occurring in the United States (US), and increased substantially during the pandemic. This paper reviews the National Institute of Standards and Technology (NIST) publication base as an effective solution. The NIST Special Publication 800-66 Revision 1 was an essential standard in US healthcare, which was withdrawn in February 2024 and superseded by SP 800-66 Revision 2. This review investigates the academic papers concerning the application of the NIST SP 800-66 Revision 1 standard in the US healthcare literature. A systematic review method was used in this study to determine current knowledge gaps of the SP 800-66 Revision 1. Some limitations were employed in the search to enforce validity. A total of eleven articles were found eligible for the study. Consequently, this study suggests the necessity for additional academic papers pertaining to SP 800-66 Revision 2 in the US healthcare literature. In turn, it will enhance awareness of safeguarding electronic protected health information (ePHI), help to mitigate potential future risks, and eventually reduce breaches. 展开更多
关键词 SP 800-66 revision 1 SP 800-66 revision 2 HIPAA Compliance Security Breaches Risk management Framework (RMF) Internet of Things (IoT) Artificial Intelligence (AI)
下载PDF
Research on the Core Factors of Influencing College Students Entrepreneurial Success Rate under the Perspectives of the Law and Team Management Perspectives
2
作者 Yandong ZHANG 《International Journal of Technology Management》 2016年第3期87-89,共3页
In this paper, we conduct research on primary core factors of influencing college students' entrepreneurial success rate under the perspectives of the law and team management perspectives. College students' entrepre... In this paper, we conduct research on primary core factors of influencing college students' entrepreneurial success rate under the perspectives of the law and team management perspectives. College students' entrepreneurship education is cultivating he students innovative spirit and creative ability as the basic value tendency, in order to cultivate creative talents as the main goal of education, it is an extension of the quality-oriented education, is the comprehensive development of students' qualities of wisdom education is the all-round development of students' personality education 'is pay more attention to the body of the human spirit, the humanist education. Carrying out entrepreneurship education, the reform and development of higher education to improve the quality of talent training levels promote national independent innovation and entrepreneurship has important significance. Our research proposes the novel perspective on the issues that is meaningful. 展开更多
关键词 Core Factors Entrepreneurial Success law Team management Perspective.
下载PDF
Characteristics and trends of integrated ocean management under the framework of the United Nations Convention on the Law of the Sea
3
作者 SHI Xiaoxiao DONG Mingmei +3 位作者 JI Fengying WAN Fangfang HAN Luyao YUE Xinyang 《Marine Science Bulletin》 2021年第2期89-96,共8页
As the international community place high value on the ocean,protecting the marine environment and promoting the sustainable development of the ocean have become the consensus of all countries around the world.Integra... As the international community place high value on the ocean,protecting the marine environment and promoting the sustainable development of the ocean have become the consensus of all countries around the world.Integrated ocean management,as an important part of the ocean governance mechanism within the framework of the United Nations,have approached to the scene view of human gradually.Taking the United Nations Convention on the Law of the Sea as the framework,the current international integrated ocean management is summarized and the future development trend of ocean management is analyzed,providing reference for China to build a maritime power and a maritime community with shared future. 展开更多
关键词 United Nations Convention on the law of the Sea integrated ocean management maritime community with a shared future
下载PDF
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
4
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
下载PDF
Hodographs of the Gravitational Two-Body System and Discrepancies between Newtonian Laws of Equivalent Kepler Orbits and General Relativity
5
作者 Caesar P. Viazminsky Piere K. Vizminiska 《Applied Mathematics》 2014年第1期55-69,共15页
We show first that an orbit, which is naturally characterized by its eccentricity and semi-latus rectum, can equally be characterized by other sets of parameters, and proceed to determine mass-independent characteriza... We show first that an orbit, which is naturally characterized by its eccentricity and semi-latus rectum, can equally be characterized by other sets of parameters, and proceed to determine mass-independent characterizations. The latter is employed to obtain the laws of equivalent orbits, which by definition have the same eccentricity and orbit’s parameter [1]. These laws relate the values of the same physical observables on two equivalent orbits to the corresponding total mass;they include the laws of velocity, angular velocity, radial velocity, areal velocity, acceleration, period, energy and angular momentum. Regardless of the share of the two bodies of a fixed total mass, the same relative orbit occurs for the same initial conditions. Moreover, the same orbit can be traced by different total masses but with different relative velocities. The concept of a gravitational field generated by a set of masses is shown to be meaningful only when the center of mass is not changed by the test mass. The associated concept of the “nothing”, which is an infinitesimal mass that allows for the property just mentioned to be fulfilled, is introduced and its orbits are determined. The perturbation of the nothing orbits due to its replacement by a finite mass is determined. It is proved that such a replacement can have a qualitative effect resulting in a “phase transition” of an orbit from unbound to bound, and that the nothing’s circular orbits cannot be occupied by any material body. The Galileo law of free fall, on which the equivalence principle hinges and which is exact only for “nothing-like” falling objects, is revised to determine the duration of free fall of a body of an arbitrary mass. The wholeness of Newton’s laws and the associated concept of force as an interaction are highlighted, and some contradictions between the Newtonian laws of equivalent Kepler’s orbits and the general relativistic predictions are discussed. It is demonstrated that Newton’s law of gravitation is not an approximation of Einstein field Equations even in the case of a static weak field. However, both theories have a common limit corresponding to the case in which the alien concept of a field can be incorporated in the Newtonian theory. We also show that the relative velocity’s hodograph [2-4], the alternative Laplace-Runge-Lenz (LRL) vector derived by Hamilton [4-6], as well as an infinite set of LRL vectors, result all from one vector. The hodograph is a proper circular arc for hyperbolic motion, a circle less a point for parabolic motion, and a full circle for bound motion. 展开更多
关键词 Hodographs LRL Vector lawS of EQUIVALENT ORBITS Revised Galileo law of Free Fall Equivalence Principle
下载PDF
Conflict: Efficient State or State Under the Rule of Law?-- The Hungarian Case of the Victory of the Efficient State over the State Under the Rule of Law
6
作者 Maria BORDAS 《International Relations and Diplomacy》 2015年第3期151-179,共29页
This study is seeking an answer as to whether the efficient state and the state under the rule of law are indeed irreconcilable, as well as to whether these two categories are by nature to be seen as contrary concepts... This study is seeking an answer as to whether the efficient state and the state under the rule of law are indeed irreconcilable, as well as to whether these two categories are by nature to be seen as contrary concepts. The basic issue is whether efficiency is to be handled as an "extralegal" category, or whether legal regulation, in accordance with public administration traditions in Europe, can in itself meet the requirement of efficiency. Also the study presents the formation of the issue of conflict between the effective state and the state under the rule of law in Hungary after the election held in 2010 in the practice of economic policy and legislation of the Orban government. We are trying to answer the question of the tendency of power concentration to really menace the principles of a traditionally-formed state under the rule of law, as well as whether the economic policy of the government can be implemented effectively in a strongly centralized political and state administrative system. 展开更多
关键词 Efficient state rule of the law CONSTITUTIONALISM New Public management neoliberalism Weberianmodel CONSTITUTIONALISM economic governance
下载PDF
Empirical Test of Wagner's law in New Public Management Countries' Tax Revenue
7
作者 Hao Xiao-wei Liu Hua-ping 《International Journal of Technology Management》 2015年第11期87-92,共6页
The essence of empirical test of Wagner characteristic in new public management countries' tax revenue is to test the influence of economic growth on tax growth since new public management movement. Under IMF statist... The essence of empirical test of Wagner characteristic in new public management countries' tax revenue is to test the influence of economic growth on tax growth since new public management movement. Under IMF statistical framework, by using E-G two-step method in co-integration test and Granger causality test and empirically testing of the gross tax revenue and classified tax revenue in Australian, Canada, France, America, Britain these five countries, we can find that most indicators in most countries do not confirm to Wagner' s law. With the growth of GDP, tax revenue as a percentage of GDP rises periodically but not permanently. This period can be called the validity period of Wagner' s law in financial scale. 展开更多
关键词 New Public management Wagner' s law Tax Revenue Validity Period of Wagner' s law
下载PDF
Model of Pollution Management Control in Badung River: Enhancing Role of Traditional Law on Common Resource
8
《Sociology Study》 2012年第2期120-128,共9页
Badung River in the Denpasar city of Bali Province, Indonesia, faces many challenging issues recently. As a common pool resource, the river has been under pressure from many activities including household activities w... Badung River in the Denpasar city of Bali Province, Indonesia, faces many challenging issues recently. As a common pool resource, the river has been under pressure from many activities including household activities which dump household wastes, and pollution externalities arising from dyeing and screen-printing of fabric industries. Conventional approach to control the pollution might not be effective since it will end up in zero sum game. This paper attempts to explore the role of traditional institituion in managing common pool resource such as controlling river pollution. This research is aimed to know the effectiveness of traditional law on managing pollution of printing and dyeing industries on this big river. Survey method was used for collecting primary data and then the data was analyzed by ordinal regression to determine the effect of internal and external factors which influence the intensity of pollution. The result indicates that even though traditional might help to influence household and industry's decision making, it might not sufficient enough to reduce the pollution of the river. Other factors are influencing the waste management, such as level of waste management knowledge of the entrepreneur, the attitude of the entrepreneur toward public program especially on waste and pollution management, the financial support, and the education level of government supervision. Furthermore, Government of Denpasar City need to arrange policy that giving incentive to businessman who handling waste properly and also giving reward to traditional organization who implementing local wisdom and norm to control river pollution strictly. 展开更多
关键词 Pollution management dyeing and screen-printing industries pollution externalities traditional law common pool resource
下载PDF
Improving the Management and Guidance System, and Enhancing the Development Quality of Law Schools and Colleges
9
作者 FU Zitang 《Frontiers of Law in China-Selected Publications from Chinese Universities》 2024年第2期139-149,共11页
Legal education and legal theory research are on the honorable mission of cultivating high-quality rule-of-law personnel and providing theoretical support for the rule of law in China, and play an important role in ad... Legal education and legal theory research are on the honorable mission of cultivating high-quality rule-of-law personnel and providing theoretical support for the rule of law in China, and play an important role in advancing the law-based governance in all fields. The Opinions on Strengthening Legal Education and Legal Theory Research in the New Era (hereinafter referred to as the “Opinions” ) issued by the General Office of the Central Committee of the Communist Party of China (CPC) and the General Office of the State Council in 2023 to meet the needs of legal education and legal theory research at present and in the future further clarifies the directions of legal education and legal theory research, and carries great importance for strengthening legal education, deepening legal research, improving the cultivation quality of rule-of-law personnel, and advancing law-based governance in all fields. The Opinions also puts forward new requirements for thoroughly implementing the spirit of the 20th National Congress of the CPC and XI Jinping Thought on the Rule of Law, and continuously cultivating high-quality rule-of-law personnel. 展开更多
关键词 law schools and colleges management and guidance system legal education
原文传递
Newly Revised Implementing Rulesof the Patent Law of the People's Republic of China Approved by the State Council
10
《China's Foreign Trade》 2001年第7期37-38,共2页
关键词 Newly Revised Implementing Rulesof the Patent law of the People’s Republic of China Approved by the State Council
下载PDF
Revision of Trade Union Law: For Better Protection of Workers' Rights and Interests
11
作者 STAFF REPORTER 《The Journal of Human Rights》 2002年第1期13-15,共3页
On October 27, 2001, the Standing Committee of the National People's Congress adopted a decision on revision of the People's Republic of China Trade Union Law. Guan Huai, legal advisor to the All-China Federat... On October 27, 2001, the Standing Committee of the National People's Congress adopted a decision on revision of the People's Republic of China Trade Union Law. Guan Huai, legal advisor to the All-China Federation of Trade Unions, had the following to say in an interview with the Human Rights: 展开更多
关键词 For Better Protection of Workers revision of Trade Union law Rights and Interests
下载PDF
Impact of slope farmland use change on ecosystem services value in China,2000-2020 被引量:1
12
作者 ZENG Jie BIAN Jiao-jiao CHEN Wan-xu 《Journal of Mountain Science》 SCIE CSCD 2023年第3期821-833,共13页
Slope farmland is an important component of farmland resources in China.The utilization and change of slope farmland have significant effects on ecosystems,and understanding the impact of slope farmland change on ecos... Slope farmland is an important component of farmland resources in China.The utilization and change of slope farmland have significant effects on ecosystems,and understanding the impact of slope farmland change on ecosystem services(ESs)is critical for effective land utilization and ecosystem protection.This study aims to analyze slope farmland changes in China between 2000 and 2020 and quantify the impact of these changes on ESs by the use of a land use dynamic attitude study,and an ecosystem services value(ESV)equivalent.Results show that the area of slope farmland in China was mainly concentrated on slopes of 2°-6°,and exhibited a downward trend between 2000 and 2020.There were significant differences in the spatial distribution of the farmland,which was mainly located in the Taihang,Qinling,Wushan,and Xuefeng mountains.ESV increased by$179.235 million due to the conversion between slope farmland and forest,grassland,and construction land from 2000-2010.Conversely,from 2010 to 2020,ESV decreased by$2613.919 million due to the conversion of forest and grassland to slope farmland as well as the conversion of slope farmland to construction land. 展开更多
关键词 Slope farmland change Revised benefit transfermethod Ecosystemservicesvalue Ecosystem services management Slope farmland utilization China
下载PDF
THE LOW MACH NUMBER LIMIT FOR ISENTROPIC COMPRESSIBLE NAVIER-STOKES EQUATIONS WITH A REVISED MAXWELL'S LAW
13
作者 胡玉玺 王召 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1239-1250,共12页
We investigate the low Mach number limit for the isentropic compressible NavierStokes equations with a revised Maxwell's law(with Galilean invariance) in R^(3). By applying the uniform estimates of the error syste... We investigate the low Mach number limit for the isentropic compressible NavierStokes equations with a revised Maxwell's law(with Galilean invariance) in R^(3). By applying the uniform estimates of the error system, it is proven that the solutions of the isentropic Navier-Stokes equations with a revised Maxwell's law converge to that of the incompressible Navier-Stokes equations as the Mach number tends to zero. Moreover, the convergence rates are also obtained. 展开更多
关键词 isentropic compressible Navier-Stokes equations low Mach number limit revised Maxwell's law
下载PDF
Typical Experience and Legal Problems of Urban-rural Integration Development in Counties of Chongqing
14
作者 Jicheng SU 《Asian Agricultural Research》 2023年第3期17-20,25,共5页
With"people as the core",Chongqing vigorously explores the reform of integration of urban and rural elements in counties,gradually breaks down the institutional barriers that hinder the free flow and equal e... With"people as the core",Chongqing vigorously explores the reform of integration of urban and rural elements in counties,gradually breaks down the institutional barriers that hinder the free flow and equal exchange of urban and rural elements,and promotes the balanced development of land,talent,medical care,pension,education and service towards"equalization"and"integration".Some typical experience practices and outstanding results have been formed.At the same time,restricted by system,capital,technology and other factors,there are still many"pain points"and"difficulties"in the integration of urban and rural development in counties of Chongqing.Based on the reform practice,some countermeasures and suggestions for the integrated development of urban and rural elements in counties of Chongqing were put forward. 展开更多
关键词 COUNTY Development law management
下载PDF
Design of an Index System for Deep Groundwater Management Efficiency Evaluation: A Case Study in Tianjin City, China 被引量:1
15
作者 NAN Tian SHAO Jingli +2 位作者 CAO Xiaoyuan ZHANG Qiulan CUI Yali 《Chinese Geographical Science》 SCIE CSCD 2016年第3期325-338,共14页
An effective evaluation system can provide specific and practical suggestions to the deep groundwater management. But such kind of evaluation system has not been proposed in China. In this study, an evaluation index s... An effective evaluation system can provide specific and practical suggestions to the deep groundwater management. But such kind of evaluation system has not been proposed in China. In this study, an evaluation index system is specifically developed to evaluate deep groundwater management efficiency. It is composed of three first-level indicators(law enforcement capability, management ability, and management effectiveness) and eleven second-level indicators. The second-level indicators include seven mandatory indicators and four optional indicators. Piecewise linear function is used to normalize the quantitative indicators, and expert scoring method and questionnaire survey method are used to normalize the qualitative indicators. Then a comprehensive indicator weighting evaluation method is used to evaluate the first-level indicators and the target topic. A case study is carried out to evaluate deep groundwater management efficiency in Tianjin City. According to the evaluation score in each period, the management efficiency of every district in Tianjin City gradually improved. The overall evaluation score in the early deep groundwater extraction period is 0.12. After a series of deep groundwater protection efforts, this score reached to 0.61 in 2007, and met the regulation criteria. The evaluation results also showed that the further groundwater management efforts in Tianjin City should be focused on building a dynamic database to collect comprehensive deep well-log data; and on a reasonable design and distribution of the groundwater monitoring network. It demonstrated that the index system is suitable to locate the deficiencies of current groundwater management systems and to guide further improvements. It can then be used to protect deep groundwater. 展开更多
关键词 deep groundwater management evaluation index system law enforcement capability management ability management effectiveness
下载PDF
The Changing Labour Relations during the Period of Economic Reform:A Case Study of Chinese Township and Village Enterprises in Yangtze River Delta
16
作者 金靖 《海外英语》 2011年第5X期317-318,321,共3页
The economic reform launched in the People's Republic of China(China) led to a rapid growth in non-state sectors.Various forms of corporate governances and ownerships emerged during the last two decades,especially... The economic reform launched in the People's Republic of China(China) led to a rapid growth in non-state sectors.Various forms of corporate governances and ownerships emerged during the last two decades,especially the Township and Village Enterprises owned by local residents.This article is conducted on the changing labour relations in Chinese Township and Village Enterprises(TVEs) despite their increasing contributions to China's transition from planned economy to market economy,and studies the labour market and the Labour Law to understand the unique labour mobility and to test the relationship between Human Resource Management(HRM) practice and the performance among TVEs. 展开更多
关键词 Township and VILLAGE Enterprises(TVEs) labour RELATIONS Human Resource management(HRM) labour law
下载PDF
Management of metal-on-metal hip implant patients: Who,when and how to revise?
17
作者 Reshid Berber John A Skinner Alister J Hart 《World Journal of Orthopedics》 2016年第5期272-279,共8页
The debate on how best to manage patients with metal-on-metal(MOM) hip implants continues. With over 1 million patients affected worldwide, the impact is far reaching. The majority of the aggressive failures of MOM hi... The debate on how best to manage patients with metal-on-metal(MOM) hip implants continues. With over 1 million patients affected worldwide, the impact is far reaching. The majority of the aggressive failures of MOM hip implants have been dealt with by revision hip surgery, leaving patients with a much more indolent pattern of failure of devices that have been in situ for more than 10 years. The longer-term outcome for such patients remains unknown, and much debate exists on how best to manage these patients. Regulatory guidance is available but remains open to interpretation due to the lack of current evidence and long-term studies. Metal ion thresholds for concern have been suggested at 7 ppb for hip resurfacing arthroplasty and below this level for large diameter total hip arthroplasties. Soft tissue changes including pseudotumours and muscle atrophy have been shown to progress, but this is not consistent. New advanced imaging techniques are helping to diagnose complications with metal hips and the reasons for failure, however these are not widely available. This has led to some centres to tackle difficult cases through multidisciplinary collaboration, for both surgical management decisions and also follow-up decisions. We summarise current evidence and consider who is at risk, when revision should be undertaken and how patients should be managed. 展开更多
关键词 METAL on METAL hip management MULTIDISCIPLINARY revision Decision
下载PDF
COMPREHENSIVE DEVELOPMENT OF AGRICULTURE IN THE LOESS PLATEAU AREA
18
作者 Li Zhuchen 《Chinese Geographical Science》 SCIE CSCD 1992年第1期57-64,共8页
The Loess Plateau is one of China s developing areas where socio-econ-omy is backward,ecological environment deteriorated and people’s life difficult.The purpose of carrying out comprehensive development of the area... The Loess Plateau is one of China s developing areas where socio-econ-omy is backward,ecological environment deteriorated and people’s life difficult.The purpose of carrying out comprehensive development of the area’s agriculture is,in essence,to open up new fields of agro-production,to intensify the utilization of related resources,to raise productivity and to win bigger output.The decision is important,as by so doing,the physical landscape could be tranformed,the local economy could be flourished,and the people’s standard of living could be improved,and moreover the national development strategy of"depending on the East and shifting to the West"and building Shanxi Province into an energy and chemical industrial base could be realized.Based on field investigations in recent years,the auther proposed the purpose,target,principles,steps,tactics and strategies for the comprehensive development of the are’s agriculture. 展开更多
关键词 DEVELOPMENT management economic law ecological benefits comprehensive development
下载PDF
New Strategy of IPACS Design and Energy Management for Spacecrafts
19
作者 张景瑞 《Journal of Beijing Institute of Technology》 EI CAS 2006年第3期300-305,共6页
The design problem of an integrated power and attitude control system (IPACS) for spacecrafts is investigated. A Lyapunov-typed IPACS controller is designed for a spacecraft equipped with 4 flywheels (3 orthogonal ... The design problem of an integrated power and attitude control system (IPACS) for spacecrafts is investigated. A Lyapunov-typed IPACS controller is designed for a spacecraft equipped with 4 flywheels (3 orthogonal + 1 skew). This controller keeps in the nonlinear properties of original systems, so the control result can be more precise. A control law of the flywheels is also proposed to accomplish the attitude control and energy storage simultaneously. Aiming at the limitations existing in the power conversion characteristic and the wheel's motor, a new strategy of energy management is proposed. The strategy can not only make the charged/discharged energy reaching balance in each orbital period, but also sufficiently utilize the power provided by the solar arrays. Therefore, the size and mass of solar arrays can be decreased, and the cost of spacecraft can be economized. A simulation example illustrates the validity of the designed IPACS. 展开更多
关键词 integrated power and attitude control system (IPACS) Lyapunov approach energy management control law of the flywheels
下载PDF
Strengthen Construction of Standardization to Promote Development of Petrochemical Enterprises
20
作者 Dong Wenhuan 《China Standardization》 2006年第4期28-32,共5页
The importance and several principles in the enterprises standardization work were described. The significance of adopting advanced international standardization system and of perfecting the standardization management... The importance and several principles in the enterprises standardization work were described. The significance of adopting advanced international standardization system and of perfecting the standardization management system was also discussed. 展开更多
关键词 standardization formulate revision management
下载PDF
上一页 1 2 240 下一页 到第
使用帮助 返回顶部