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Two-Stage Planning of Distributed Power Supply and Energy Storage Capacity Considering Hierarchical Partition Control of Distribution Network with Source-Load-Storage
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作者 Junhui Li Yuqing Zhang +4 位作者 Can Chen Xiaoxiao Wang Yinchi Shao Xingxu Zhu Cuiping Li 《Energy Engineering》 EI 2024年第9期2389-2408,共20页
Aiming at the consumption problems caused by the high proportion of renewable energy being connected to the distribution network,it also aims to improve the power supply reliability of the power system and reduce the ... Aiming at the consumption problems caused by the high proportion of renewable energy being connected to the distribution network,it also aims to improve the power supply reliability of the power system and reduce the operating costs of the power system.This paper proposes a two-stage planning method for distributed generation and energy storage systems that considers the hierarchical partitioning of source-storage-load.Firstly,an electrical distance structural index that comprehensively considers active power output and reactive power output is proposed to divide the distributed generation voltage regulation domain and determine the access location and number of distributed power sources.Secondly,a two-stage planning is carried out based on the zoning results.In the phase 1 distribution network-zoning optimization layer,the network loss is minimized so that the node voltage in the area does not exceed the limit,and the distributed generation configuration results are initially determined;in phase 2,the partition-node optimization layer is planned with the goal of economic optimization,and the distance-based improved ant lion algorithm is used to solve the problem to obtain the optimal distributed generation and energy storage systemconfiguration.Finally,the IEEE33 node systemwas used for simulation.The results showed that the voltage quality was significantly improved after optimization,and the overall revenue increased by about 20.6%,verifying the effectiveness of the two-stage planning. 展开更多
关键词 Zoning control two-stage planning site selection and capacity determination optimized scheduling improved ant lion algorithm
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Evaluation of Malaria Transmission and Vector Control Strategies in the Dry Season in the Cotonou V Health Zone, Benin, West Africa
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作者 Tokponnon Filémon Osse Razaki +6 位作者 Zannou Ahissou Robert Franck Alapini Marlène Sare Dabou Zoulkifilou Houessinon Festus Gounou Yerima Idayath Sominahoun André Akogbeto Martin 《Advances in Entomology》 2023年第3期156-171,共16页
The anarchic urbanization of certain African cities favors the multiplication of the malaria parasite. Thus, the urgent mobilization of African cities is essential to combat this health risk. It is, therefore, with th... The anarchic urbanization of certain African cities favors the multiplication of the malaria parasite. Thus, the urgent mobilization of African cities is essential to combat this health risk. It is, therefore, with the objective of contributing to the investigation of problem areas that the present study evaluates malaria transmission and vector control strategies in the Cotonou V health zone in particular. This is a cross-sectional study taking into account four neighborhoods, including Wologuèdè, Sainte Rita, Gbèdjromèdé and the area around Etoile Rouge. Two nocturnal captures on voluntary humans and the method of spray were carried out in the dry season from December 2021 to February 2022. On the captured Anopheles, the ELISA Circum-Sporozoite Protein test was performed to determine the infectivity and calculate some transmission parameters. Finally, we conducted a survey using the second stage sampling method with one step to ask selected households about their knowledge of vector control methods, their use and the physical integrity of LLINs. We collected 2386 culicidae of which the majority was Culex quinquefasciatus. After the ELISA test, the 29 Anopheles tested, showed no infectivity, i.e. an EIR of 0 pi/h/n. In addition, 99% of the populations in the Cotonou V area use LLINs to protect themselves. However, coils, door and window screens, aerosol sprays, skin and household repellents, and periodic indoor spraying were used. Finally, the majority of nets observed had T1 tears, but there were also T2, T3 and T4 nets (P-value = 0.0). This study confirms that malaria transmission during the dry season in the Cotonou V health zone is almost negligible but not non-existent. Also, populations are exposed to the nuisance of Culex quinquefasciatus mosquitoes continuously throughout the year. 展开更多
关键词 ANOPHELES Transmission Urban Malaria Cotonou V Health zone Vector control
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A test sequence generation method of zone controller based on timed automata 被引量:4
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作者 SONG Shuang CHEN Yue-dong 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2019年第3期266-276,共11页
In order to solve the problem of artificial generation and low efficiency of test sequences for zone controller (ZC), a model-based automatic generation method of test sequence is proposed. Firstly, the timed automata... In order to solve the problem of artificial generation and low efficiency of test sequences for zone controller (ZC), a model-based automatic generation method of test sequence is proposed. Firstly, the timed automata model is established based on function analysis of the zone controller, and the correctness of the model is verified by UPPAAL. Then by parsing the timed automata model files, state information and transition conditions can be extracted to generate test case sets. Finally, according to the serialization conditions of test cases, the test cases are serialized into test sequences by using the improved depth first search algorithm. A case, the ZC controls the train running within its jurisdiction, shows that the method is correct and can effectively improve the efficiency of test sequence generation. 展开更多
关键词 test sequence zone controller (ZC) timed automata model file parsing case serialization
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Sheet Bulk Forming of Thin-Walled Components with External Gearing through Upsetting Using Controllable Deformation Zone Method 被引量:1
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作者 Xincun Zhuang Meile Liang +2 位作者 Shengfa Zhu Yin Zhu Zhen Zhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第5期282-295,共14页
Sheet-bulk metal forming(SBMF)is a promising process for manufacturing complex sheet components with functional elements.In this study,the entire forming process for a typical thin-walled component with external geari... Sheet-bulk metal forming(SBMF)is a promising process for manufacturing complex sheet components with functional elements.In this study,the entire forming process for a typical thin-walled component with external gearing is investigated,including sheet forming and bulk forming processes.Deep drawn cups are prepared during sheet forming;subsequently,upsetting is performed on the sidewall to form external gearing.The upsetting method performed is known as upsetting with a controllable deformation zone(U-CDZ).Compared with the conventional upsetting method,a floating counter punch with a counter force is used in the U-CDZ method such that the forming mechanism is changed into the accumulation of the deformation zone instead of deformation throughout the entire sidewall.The effects of the counter force and material flow are investigated to understand the mechanism.The forming quality,i.e.,the formfilling and effective strain distribution,improved,whereas a high forming load is avoided.In addition,a punch with a lock bead is used to prevent folding at the inner corner during the experiment. 展开更多
关键词 Sheet-bulk metal forming Thin-walled components External gearing controllable deformation zone
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Adaptive Variable Structure Control of MIMO Nonlinear Systems with Time-varying Delays and Unknown Dead-zones 被引量:7
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作者 Tian-Ping Zhang Cai-Ying Zhou Qing Zhu 《International Journal of Automation and computing》 EI 2009年第2期124-136,共13页
In this paper, adaptive variable structure neural control is presented for a class of uncertain multi-input multi-output (MIMO) nonlinear systems with state time-varying delays and unknown nonlinear dead-zones. The ... In this paper, adaptive variable structure neural control is presented for a class of uncertain multi-input multi-output (MIMO) nonlinear systems with state time-varying delays and unknown nonlinear dead-zones. The unknown time-varying delay uncer- tainties are compensated for using appropriate Lyapunov-Krasovskii functionals in the design. The approach removes the assumption of linear function outside the deadband without necessarily constructing a dead-zone inverse as an added contribution. By utilizing the integral-type Lyapunov function and introducing an adaptive compensation term for the upper bound of the residual and optimal approximation error as well as the dead-zone disturbance, the closed-loop control system is proved to be semi-globally uniformly ultimately bounded. In addition, a modified adaptive control algorithm is given in order to avoid the high-frequency chattering phenomenon. Simulation results demonstrate the effectiveness of the approach. 展开更多
关键词 Adaptive control neural networks (NNs) variable structure control DEAD-zone nonlinear time-varying delay systems.
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Evaluation of Merge Control Strategies at Interstate Work Zones under Peak and Off-Peak Traffic Conditions 被引量:1
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作者 Ossama E. Ramadan Virginia P. Sisiopiku 《Journal of Transportation Technologies》 2016年第3期118-130,共13页
Maintenance and rehabilitation projects of interstate facilities typically mandate lane closures. Lane closures require merging maneuvers that often result in reduced speeds and traffic bottlenecks. Work zone impacts ... Maintenance and rehabilitation projects of interstate facilities typically mandate lane closures. Lane closures require merging maneuvers that often result in reduced speeds and traffic bottlenecks. Work zone impacts on traffic operations are magnified when project durations are extended. Conventionally, work zone traffic control plans are developed to address work zone impacts. This study evaluated various merge control strategies at interstate work zones peak and off-peak traffic conditions and summarized related impacts. A comprehensive microscopic simulation model was developed in full consideration of driver/vehicle behavior at work zones. The analysis of simulation results revealed that merge control strategies, when implemented during peak and off-peak conditions, can preserve the level of service and provide favorable mobility, safety, and environmental impacts. In addition, results indicate that transportation agencies’ practice of scheduling work zone activities during the off-peak may not be the most optimum approach. Overall, the findings of this study highlight the need for evaluation of work zone scheduling practices in full consideration of agency, user, and project costs. 展开更多
关键词 Traffic Simulation BOTTLENECKS Work zone Traffic control Traffic Congestion
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ADAPTIVE CONTROL OF FLEXIBLE BEAM WITH UNKNOWN DEAD-ZONE IN THE DRIVING MOTOR 被引量:2
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作者 WangXingsong HongHenry SuChunyi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第3期327-331,共5页
Adaptive control of a flexible beam system preceded by an unknown dead-zonein the driving motor is investigated in state space form. By introducing an important lemma forsimplifying error equation between the flexible... Adaptive control of a flexible beam system preceded by an unknown dead-zonein the driving motor is investigated in state space form. By introducing an important lemma forsimplifying error equation between the flexible beam model and the matching reference model, arobust adaptive control scheme is developed by involving the dead-zone inverse terms. The newadaptive control law ensures global stability of the entire system and achieves desired trackingprecision even when the slopes of the dead-zone are not equal. Simulations performed on a typicalflexible beam system illustrate and clarify the validity of this approach. 展开更多
关键词 Adaptive control Flexible beam DEAD-zone
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Adaptive Fuzzy Control for a Class of MIMO Nonlinear Systems with Unknown Dead-zones 被引量:14
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作者 ZHANG Tian-Ping YI Yang 《自动化学报》 EI CSCD 北大核心 2007年第1期96-100,共5页
A design scheme of adaptive fuzzy controller for a class of uncertain MIMO nonlinear systems with unknown dead-zones and a triangular control structure is proposed in this pa-per. The design is based on the principle ... A design scheme of adaptive fuzzy controller for a class of uncertain MIMO nonlinear systems with unknown dead-zones and a triangular control structure is proposed in this pa-per. The design is based on the principle of sliding mode control and the property of Nussbaum function. The approach does not require a priori knowledge of the signs of the control gains and the upper bounds and lower bounds of dead-zone parameters to be known a priori. By introducing the integral-type Lyapunov function and adopting the adaptive compensation term of the upper bound of the optimal approximation error and the dead-zone disturbance, the closed-loop control system is proved to be semi-globally stable in the sense that all signals involved are bounded, with tracking errors converging to zero. 展开更多
关键词 自适应控制 模糊控制 滑模控制 NUSSBAUM函数
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Adaptive Fuzzy Control for Unknown Nonlinear Systems with Perturbed Dead-zone Inputs 被引量:6
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作者 LI Ping JIN Fu-Jiang 《自动化学报》 EI CSCD 北大核心 2010年第4期573-579,共7页
关键词 自适应系统 模糊系统 自动化 稳定性
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Adaptive variable structure control for large-scale time-delayed systems with unknown nonlinear dead-zone 被引量:1
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作者 Shen Qikun Zhang Tianping 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第4期865-870,共6页
The problem of adaptive fuzzy control for a class of large-scale, time-delayed systems with unknown nonlinear dead-zone is discussed here. Based on the principle of variable structure control, a design scheme of adapt... The problem of adaptive fuzzy control for a class of large-scale, time-delayed systems with unknown nonlinear dead-zone is discussed here. Based on the principle of variable structure control, a design scheme of adaptive, decentralized, variable structure control is proposed. The approach removes the conditions that the dead-zone slopes and boundaries are equal and symmetric, respectively. In addition, it does not require that the assumptions that all parameters of the nonlinear dead-zone model and the lumped uncertainty are known constants. The adaptive compensation terms of the approximation errors axe adopted to minimize the influence of modeling errors and parameter estimation errors. By theoretical analysis, the closed-loop control system is proved to be semiglobally uniformly ultimately bounded, with tracking errors converging to zero. Simulation results demonstrate the effectiveness of the approach. 展开更多
关键词 nonlinear dead-zone decentralized control adaptive control variable structure control
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Assessing Work Zone Traffic Control Options for 3-to-1 Lane Closures 被引量:1
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作者 Troyee Saha Virginia P. Sisiopiku 《Journal of Transportation Technologies》 2020年第1期50-64,共15页
The presence of highway construction zones hinders mobility and affects traffic operations. A 2002 study by Wunderlich & Hardesty reported that nearly 20% of the National Highway System roads have scheduled constr... The presence of highway construction zones hinders mobility and affects traffic operations. A 2002 study by Wunderlich & Hardesty reported that nearly 20% of the National Highway System roads have scheduled construction work during the peak construction season. Additionally, approximately 24% of non-recurring delays on freeways are caused by work zones. To minimize time lost by travelers due to work zone induced traffic congestion, it is important to efficiently plan temporary traffic control (TTC) at work zones. Earlier research conducted by Sisiopiku & Ramadan, 2017 confirms that the majority of State Departments of Transportation currently rely on their earlier experience when planning for work zones, rather than consider operational and safety impacts. Using a study corridor in Birmingham, Alabama as a test bed, this study investigated the operational impacts of TTC options for work zones with 3-to-1 lane drop configuration using traffic data collected from the Alabama Department of Transportation. The VISSIM simulation platform was used to conduct the experiments. The experimental design considered two TTC strategies (i.e., static late and early merge) under 3-to-1 lane drop configuration for work-space length of 500 ft for long- and short-term lane closures. The study concluded that the 3-to-1 lane-drop configuration should not be scheduled for long-term duration. Maintenance work can be scheduled from midnight to early morning and under the 3-to-1 lane closure scenario the performance of early and late merge traffic control is similar. Overall, this study used simulation modeling to compare the effectiveness of two traffic control strategies at work zones on the basis of different performance measures. The results provide information about the impact of each control strategy on density, speed, travel time etc. They also help determine what time of the day is best for lane closings in order to reduce adverse impacts from capacity reduction. Thus, the findings are expected to provide valuable guidance for agencies responsible for planning, design, and operations of work zones in the future. 展开更多
关键词 Work zone Traffic control Early MERGE LATE MERGE VISSIM Simulation
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ANALYSIS MODEL ON GRADUAL CHANGE PRINCIPLE OF EFFECT ZONES OF LAYER FACE FOR ROLLED CONTROL CONCRETE DAM 被引量:1
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作者 顾冲时 宋敬衖 方海挺 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第11期1523-1529,共7页
The effect zones of layer face for RCC (rolled control concrete) dam have gradual change characteristics. Based on the analysis thought of complex material, a model was built to analyze above principle of RCC dam by... The effect zones of layer face for RCC (rolled control concrete) dam have gradual change characteristics. Based on the analysis thought of complex material, a model was built to analyze above principle of RCC dam by use of series-wound and shunt-wound connection. Some methods were proposed to determine the instantaneous Young's modulus, delayed Young's modulus and viscosity coefficient of effect zones of layer face. Above models and methods were used to mine the principle of gradual change of key calculation parameters which can response the characteristics of effect zones. The principle of gradual change was described. A model was established to analyze the threedimensional viscoelastic problem of RCC dam. Above programs were developed. The examples show that the proposed models and methods to determine the key calculation parameters of effect zones can reflect the status of RCC dam accurately. 展开更多
关键词 (rolled control concrete dam) effect zones calculation parameter principle of gradual change viscoelastic model
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A novel strategy of smart manipulation by micro-scale oscillatory networks of the reactionary zones for enhanced extreme thrust control of the next-generation solid propulsion systems
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作者 Alexander N.Lukin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2018年第5期635-642,共8页
The main aim of this research is to get a better knowledge and understanding of the micro-scale oscillatory networks behavior in the solid propellants reactionary zones. Fundamental understanding of the micro-and nano... The main aim of this research is to get a better knowledge and understanding of the micro-scale oscillatory networks behavior in the solid propellants reactionary zones. Fundamental understanding of the micro-and nano-scale combustion mechanisms is essential to the development and further improvement of the next-generation technologies for extreme control of the solid propellant thrust. Both experiments and theory confirm that the micro-and nano-scale oscillatory networks excitation in the solid propellants reactionary zones is a rather universal phenomenon. In accordance with our concept,the micro-and nano-scale structures form both the fractal and self-organized wave patterns in the solid propellants reactionary zones. Control by the shape, the sizes and spacial orientation of the wave patterns allows manipulate by the energy exchange and release in the reactionary zones. A novel strategy for enhanced extreme thrust control in solid propulsion systems are based on manipulation by selforganization of the micro-and nano-scale oscillatory networks and self-organized patterns formation in the reactionary zones with use of the system of acoustic waves and electro-magnetic fields, generated by special kind of ring-shaped electric discharges along with resonance laser radiation. Application of special kind of the ring-shaped electric discharges demands the minimum expenses of energy and opens prospects for almost inertia-free control by combustion processes. Nano-sized additives will enhance self-organizing and self-synchronization of the micro-and nano-scale oscillatory networks on the nanometer scale. Suggested novel strategy opens the door for completely new ways for enhanced extreme thrust control of the solid propulsion systems. 展开更多
关键词 Solid propulsion systems EXTREME thrust control Reactionary zoneS MICRO-SCALE OSCILLATORY NETWORKS Self-organized wave patterns Energy-releasing areas
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THE CHARACTERISTICS AND MODELLING EXPERIMENTS ON THE DEPOSIT-CONTROLLING STRUCTURE OF SHEAR-ZONE GOLD DEPOSIT IN CHINA
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作者 Wu Xueyi(Institute of Geochemistry, Academia Sinica, Guiyang, 550002, China) 《Geotectonica et Metallogenia》 1996年第Z1期31-33,共3页
THE CHARACTERISTICS ANDMODELLING EXPERIMENTS ON THEDEPOSIT-CONTROLLING STRUCTUREOF SHEAR-ZONE GOLD DEPOSITIN CHINAWu Xueyi(Institute of Geochemistry, Academia Sinica, Guiyang, 550002, China)shear zone, gold-controlled... THE CHARACTERISTICS ANDMODELLING EXPERIMENTS ON THEDEPOSIT-CONTROLLING STRUCTUREOF SHEAR-ZONE GOLD DEPOSITIN CHINAWu Xueyi(Institute of Geochemistry, Academia Sinica, Guiyang, 550002, China)shear zone, gold-controlled structure, modelling experimentThe shear-zone gold deposits found in China can be divided into four types: (1) gold deposits controlled by the ductile shear-zones; (2) gold deposits controlled by the brittle-ductile shear zones; (3) gold deposits conntrolled by the ductile-brittle shear zones; (4) gold deposits controlled by the brittle shear zones. These gold deposits mostly occurred in the regions with higher abundance of gold, which underwent a long and complicated evolution-ary process and had obvious zoning and multiperiod metallogenic feature. The modelling exper-imental result of gold-controlled structure shows that the thermodynamics of compresso-shear structures made gold mobilizing and migrating in the earlier stage of shear zone; and that the extension process did 展开更多
关键词 SHEAR zone gold-controlled STRUCTURE modelling experiment
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Zoning Control of Health of Farmland System
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作者 Ziwei WANG Peng FAN +2 位作者 Lei WANG Xihui YANG Qingwei YANG 《Meteorological and Environmental Research》 2023年第6期69-72,共4页
In addition to the quality and quantity of farmland, the health of farmland has also become an important research direction in the field of farmland protection. In order to comprehensively evaluate the relationship an... In addition to the quality and quantity of farmland, the health of farmland has also become an important research direction in the field of farmland protection. In order to comprehensively evaluate the relationship and distribution of health and farmland production capacity, the depression area behind the Yellow River in Henan Province is taken as the research object. Using production capacity evaluation data and system health evaluation results, the health status and production capacity of farmland in the region are coupled. The results show that high productivity farmland is most distributed in areas with moderate health risks, while low productivity farmland is more distributed in areas with low health risks. Based on their coupling characteristics, the depression area behind the Yellow River can be divided into five types, and management and protection strategies can be formulated separately. 展开更多
关键词 Farmland health Healthy production capacity Zoning control
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塔里木盆地西北缘沙井子断裂带的构造特征与形成演化 被引量:3
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作者 孙崇浩 周慧 +4 位作者 罗新生 杨鹏飞 缪卫东 石磊 黄智斌 《地质科学》 CAS CSCD 北大核心 2024年第1期199-209,共11页
塔里木盆地西北缘的沙井子断裂带,位于塔北隆起的温宿凸起和北部坳陷的阿瓦提凹陷之间。它是塔里木盆地的一条一级断裂带,由沙井子断裂、英雄断裂、温宿断裂和沙南断裂组成。其中沙井子断裂是主干断裂,其它3条是其分支断裂。本轮研究新... 塔里木盆地西北缘的沙井子断裂带,位于塔北隆起的温宿凸起和北部坳陷的阿瓦提凹陷之间。它是塔里木盆地的一条一级断裂带,由沙井子断裂、英雄断裂、温宿断裂和沙南断裂组成。其中沙井子断裂是主干断裂,其它3条是其分支断裂。本轮研究新发现温宿分支断裂,并将沙南断裂解释为英雄断裂前缘的反冲断层,归属沙井子断裂带。沙井子断裂带的雏形形成于奥陶纪末—志留纪初,在泥盆纪末—石炭纪、二叠纪末—三叠纪初、侏罗纪末—白垩纪初、白垩纪末—古近纪初和新近纪—第四纪发生过多期冲断作用和新近纪末—第四纪初的张扭性构造变形后,才最终定型。沙井子断裂带是一条断控油气富集区带,温宿油田、托探1油藏、沙南1油藏、新苏地1油气藏等都受其控制。 展开更多
关键词 沙井子断裂带 温宿断裂 沙南断裂 多旋回冲断构造 断控油气富集带 塔里木盆地西北缘
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新时代生态环境分区管控成果应用体系建设的思考 被引量:1
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作者 姚懿函 李小敏 +3 位作者 李亚飞 赵果 詹丽雯 许亚宣 《环境影响评价》 2024年第3期6-12,共7页
生态环境分区管控是实施生态环境分区域差异化精准管控的环境管理制度。建立和完善成果应用体系,推动成果广泛应用、落地见效,是保持制度生命力的根本所在。在系统辨识成果体系特征的基础上,立足制度建设新阶段应用要求,提出了应用体系... 生态环境分区管控是实施生态环境分区域差异化精准管控的环境管理制度。建立和完善成果应用体系,推动成果广泛应用、落地见效,是保持制度生命力的根本所在。在系统辨识成果体系特征的基础上,立足制度建设新阶段应用要求,提出了应用体系框架,全面分析了成果应用前景;结合地方应用实践,分析了应用范围有待拓展、应用机制有待完善、成果本身有待优化、智能应用有待挖掘等不足,并提出了扩大引导宣传、完善制度保障、优化成果内容、强化平台支撑等方面的对策建议。 展开更多
关键词 生态环境分区管控 成果特征 应用体系 应用前景 应用路径
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GEOLOGICAL CHARACTERISTICS OF MAIN TYPES OF GOLD DEPOSITS IN SHEAR ZONES AND SIMULATING EXPERIMENTS ON TECTONO-CONTROLLED GOLD MINERALIZATION
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作者 Wu Xueyi Yang Yuangen Xiao Huayun and Wu Huiming(Institute of Geochemistry, Chinese Academy of Sciences, Guzyang 550002) 《Geotectonica et Metallogenia》 1998年第Z1期61-71,共11页
Gold deposits in shear zones in China can be divided into four types: ductile, brittle-ductile,ductileubrittle and britt1e. Among them, each type has its own geochemical characteristics: the Hetai gold deposit in Guan... Gold deposits in shear zones in China can be divided into four types: ductile, brittle-ductile,ductileubrittle and britt1e. Among them, each type has its own geochemical characteristics: the Hetai gold deposit in Guangdong province for example, is a kind of mylonite type gold deposit in a ductile shear zone, and the gold ore has the forms of layer and vein; the Erjia gold deposit formed in a brittleuductile shear zone, and the gold ore, being of two types, mylonite type and cataclasticaltered rock type, has the form of vein; the Shangguan gold deposit, Henan Province, was located in a ductile-brittle shear zone, and the gold ore is of two types, cataclastic-altered rock type and quartz vein type; and the Linglong gold deposit occurs in a brittle shear zone, with the main gold ore of quartz vein type having the forms of vein and lens. Simulating experiments on tectono-controlled formation of gold ores gave us the idea that not only the samples underwent crack deformation, but also changes occurred in chemical composition of minerals, and also caused gold to be remobilized and finally filled into the newlyuproduced fissures. 展开更多
关键词 SHEAR zone gold DEPOSIT tectono-controlled MINERALIZATION SIMULATING experiments
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自然生态空间用途管制制度的再造分析
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作者 郭洁 刘洋 《沈阳师范大学学报(社会科学版)》 2024年第2期45-51,共7页
在推进国家治理体系和治理能力现代化的进程中,我国现行的土地用途管制制度、自然资源用途管制制度出现“制度失灵”,无法适应当前建立覆盖“全域、全要素”国土空间用途管制制度的要求。自然生态空间用途管制制度在地类划分、分区、区... 在推进国家治理体系和治理能力现代化的进程中,我国现行的土地用途管制制度、自然资源用途管制制度出现“制度失灵”,无法适应当前建立覆盖“全域、全要素”国土空间用途管制制度的要求。自然生态空间用途管制制度在地类划分、分区、区域准入及实施保障方面,存在亟须解决的问题。自然生态空间用途管制制度构建的基本路径是,首先厘清其与土地用途管制制度的适应性,然后从界定自然资源可管制的空间范围、选择多功能管制、改革建设用地指标制度等方面实现其制度再造。自然生态空间用途管制制度的构建,有利于贯彻落实生态文明建设新理念,同时也是形成国土空间治理合力的重要制度保障。 展开更多
关键词 生态空间 用途管制 分区 区域准入
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Earthquake-controlling Processes of Detachment Zones in Eastern North China 被引量:1
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作者 SUNAiqun NIUShuyin +2 位作者 SHAOJi'an HOUQuanlin ZHANGJianzhen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期283-290,共8页
The basin-and-range area in eastern North China is known for frequent occurrence of earthquakes, their great magnitudes and heavy losses thereby incurred. Seismic studies in the past usually emphasized the intersectio... The basin-and-range area in eastern North China is known for frequent occurrence of earthquakes, their great magnitudes and heavy losses thereby incurred. Seismic studies in the past usually emphasized the intersections, inflexions and branches of the faults. However, the intensities of many great earthquakes in this area do not show linear distribution, and the epicenters are horizontally dispersed at certain depths instead of along the strike of faults. Based on the sub-mantle plume studies made by authors in the past decade, it is thought that there exists an uplifted sub-mantle plume under the fault depression area in North China. The uplifting and intrusion of mantle materials caused the upper crust to be faulted, while low-velocity and high-velocity layers are alternatively distributed in the middle crust under the influence of the mantle and the lower crust. The middle and lower crust materials were detached from the top of the sub-mantle plume to the surroundings while the sub-mantle plume materials were detached outward. When the detached middle and lower crust come to the boundary of fault basins in the upper crust, they will be obstructed by the orogenic zone and the detachment will go slower. The shearing between them will cause the stress to accumulate and release alternatively, so that earthquakes occurred frequently in the areas of sub-mantle plume and its surroundings. 展开更多
关键词 sub-mantle plume detachment belt earthquake-controlling structure low-velocity and high-conductivity zones north China basin-and range area
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