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Structural physical simulation experiment on vertical growth process of strike-slip faults in ultra-deep strata of Tarim Basin,NW China 被引量:1
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作者 NENG Yuan XIE Zhou +5 位作者 SHAO Longfei RUAN Qiqi KANG Pengfei ZHANG Jianan TIAN Zhiwen LIU Genji 《Petroleum Exploration and Development》 2025年第5期1179-1192,共14页
In the ultra-deep strata of the Tarim Basin,the vertical growth process of strike-slip faults remains unclear,and the vertical distribution of fractured-cavity carbonate reservoirs is complex.This paper investigates t... In the ultra-deep strata of the Tarim Basin,the vertical growth process of strike-slip faults remains unclear,and the vertical distribution of fractured-cavity carbonate reservoirs is complex.This paper investigates the vertical growth process of strike-slip faults through field outcrop observations in the Keping area,interpretation of seismic data from the Fuman Oilfield,Tarim Basim,NW China,and structural physical simulation experiments.The results are obtained mainly in four aspects.First,field outcrops and ultra-deep seismic profiles indicate a three-layer structure within the strike-slip fault,consisting of fault core,fracture zone and primary rock.The fault core can be classified into three parts vertically:fracture-cavity unit,fault clay and breccia zone.The distribution of fracture-cavity units demonstrates a distinct pattern of vertical stratification,owing to the structural characteristics and growth process of the slip-strike fault.Second,the ultra-deep seismic profiles show multiple fracture-cavity units in the strike-slip fault zone.These units can be classified into four types:top fractured,middle connected,deep terminated,and intra-layer fractured.Third,structural physical simulation experiments and ultra-deep seismic data interpretation reveal that the strike-slip faults have evolved vertically in three stages:segmental rupture,vertical growth,and connection and extension.The particle image velocimetry detection demonstrates that the initial fracture of the fault zone occurred at the top or bottom and then evolved into cavities gradually along with the fault growth,accompanied by the emergence of new fractures in the middle part of the strata,which subsequently connected with the deep and shallow cavities to form a complete fault zone.Fourth,the ultra-deep carbonate strata primarily develop three types of fractured-cavity reservoirs:flower-shaped fracture,large and deep fault and staggered overlap.The first two types are larger in size with better reservoir conditions,suggesting a significant exploration potential. 展开更多
关键词 strike-slip fault vertical growth evolution process structural physical simulation experiment Ordovician fractured-cavity carbonate reservoir ultra-deep Tarim Basin Fuman oilfield
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The Longmen Cloud Physics Field Experiment Base, China Meteorological Administration 被引量:3
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作者 刘显通 阮征 +18 位作者 胡胜 万齐林 刘黎平 罗亚丽 胡志群 黎慧琦 肖辉 雷卫延 夏丰 饶晓娜 冯璐 赖睿泽 吴翀 叶朗明 郭泽勇 张羽 王瑶 颜朝潮 袁锦涵 《Journal of Tropical Meteorology》 SCIE 2023年第1期1-15,共15页
Aiming at the needs of mechanism analysis of rainstorms and development of numerical prediction models in south China, the Guangzhou Institute of Tropical and Marine Meteorology of China Meteorological Administration ... Aiming at the needs of mechanism analysis of rainstorms and development of numerical prediction models in south China, the Guangzhou Institute of Tropical and Marine Meteorology of China Meteorological Administration and the Chinese Academy of Meteorological Sciences jointly set up the Longmen Cloud Physics Field Experiment Base,China Meteorological Administration. This paper introduces the instruments and field experiments of this base, provides an overview of the recent advances in retrieval algorithms of microphysical parameters, improved understanding of microphysical characteristics, as well as the formation mechanisms and numerical prediction of heavy rainfalls in south China based on the field experiments dataset. 展开更多
关键词 cloud physics heavy rainfall field experiment south China
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Simulation Experiments of Land Surface Physical Processes and Ecological Effect over Different Underlying Surface 被引量:1
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作者 LIU Shu-hua~(1,2), JIANG Hao-yu, HU Fei~2 LIU Hui-zhi~2 LIANG Fu-ming~1, WANG Jiang-hua~1(1. Group of Atmosphere Boundary Layer and turbulence, Ministry Laboratory of Storm and Drought Flood Damage, Department of Atmospheric Sciences the School of Physics Peking University, Beijing 100871, China 2. State Key Laboratories of Atmosphere Physics and Chemistry, Institute of Atmospheric Physics, Chinese Academy of Science, Beijing 100029, China) 《地球科学进展》 CAS CSCD 2004年第S1期15-20,共6页
Based on the existing Land Surface Physical Process Models(Deardorff, Dickinson, LIU, Noilhan, Seller, ZHAO), a Comprehensive Land Surface Physical Process Model (CLSPPM) is developed by considering the different phys... Based on the existing Land Surface Physical Process Models(Deardorff, Dickinson, LIU, Noilhan, Seller, ZHAO), a Comprehensive Land Surface Physical Process Model (CLSPPM) is developed by considering the different physical processes of the earth's surface-vegetation-atmosphere system more completely. Compared with SiB and BATS, which are famous for their detailed parameterizations of physical variables, this simplified model is more convenient and saves much more computation time. Though simple, the feas... 展开更多
关键词 Comprehensive land surface physical process model (CLSPPM) Simulation experiment Land surface physical process Ecological effect.
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Nuclear data measurement and propagation in Back-n experiments:methodologies and instrumentation
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作者 Min-Hao Gu Jie-Ming Xue +7 位作者 Ya-Kang Li Ping Cao Jie Ren Yong-Hao Chen Wei Jiang Han Yi Peng Hu Rui-Rui Fan 《Nuclear Science and Techniques》 2025年第11期69-82,共14页
This article introduces the methodologies and instrumentation for data measurement and propagation at the Back-n white neutron facility of the China Spallation Neutron Source.The Back-n facility employs backscattering... This article introduces the methodologies and instrumentation for data measurement and propagation at the Back-n white neutron facility of the China Spallation Neutron Source.The Back-n facility employs backscattering techniques to generate a broad spectrum of white neutrons.Equipped with advanced detectors such as the light particle detector array and the fission ionization chamber detector,the facility achieves high-precision data acquisition through a general-purpose electronics system.Data were managed and stored in a hierarchical system supported by the National High Energy Physics Science Data Center,ensuring long-term preservation and efficient access.The data from the Back-n experiments significantly contribute to nuclear physics,reactor design,astrophysics,and medical physics,enhancing the understanding of nuclear processes and supporting interdisciplinary research. 展开更多
关键词 Nuclear physics Data acquisition Data storage and management Data sharing Neutron experiments White neutron beam
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Experiences,perceptions and attitudes on providing advice on physical activity to patients with chronic ischaemic heart disease:a qualitative study in general practitioners in Germany
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作者 Alicia Prinz Sabrina Hoppe +4 位作者 Verena Leve Rik Crutzen Norbert Donner-Banzhoff Stefan Wilm Sabrina Kastaun 《Family Medicine and Community Health》 2025年第3期92-105,共14页
Background and objective The WHO emphasises the importance of integrating advice on physical activity(PA)into primary care of patients with chronic ischaemic heart disease(IHD).Similarly,the German treatment guideline... Background and objective The WHO emphasises the importance of integrating advice on physical activity(PA)into primary care of patients with chronic ischaemic heart disease(IHD).Similarly,the German treatment guideline‘Chronic Coronary Heart Disease’recommends that general practitioners(GPs)provide advice on PA to IHD patients.However,the provision of PA advice seems to be inadequately implemented in general practice.One reason is the lack of medical training in providing PA advice effectively and efficiently.International guidelines recommend such training for health professionals.This study aims to explore experiences,perceptions and attitudes,including barriers and facilitators of GPs towards the routine delivery of PA advice to IHD patients.Methods Between March and June 2023,12 face-to-face problem-centred interviews and six focus group discussions(n=37)with GPs were conducted.Interview and discussion guides were developed and pilot tested by the multi-professional study team.We used a purposive sampling strategy,and data were collected in an iterative process.Audio-recorded data were transcribed verbatim and analysed using a content structuring procedure(deductive and inductive approach).GPs were involved throughout the entire research process,for example,in multi-professional analysis groups.Results Although GPs are mostly aware of the health benefits of PA for patients with IHD,PA advice is not routinely provided.Conversations on PA tend to be rather unstructured,and advice is often addressed more generally than customised to the patients’needs and preferences.Priority is given to other lifestyle issues,such as smoking cessation.PA advice is perceived as time-consuming and rather ineffective with regard to the target behaviour.GPs frequently express frustration in this context.GPs express a lack of and simultaneously a need for communication strategies(structure and tools)that can be integrated into everyday GP practice to motivate patients to PA.Conclusion The results provide relevant insights into the current practice of GPs with regard to their attitudes on,experiences with,and requirements for the provision of PA advice to IHD patients.These results are helpful to inform the development of appropriate GP training in the provision of very brief PA advice to IHD patients. 展开更多
关键词 experiences GERMANY chronic ischaemic heart disease ihd similarlythe chronic ischaemic heart disease physical activity pa general practitioners gps provide general practitioners ADVICE
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Dynamic evolution mechanism of the fracturing fracture system——Enlightenments from hydraulic fracturing physical experiments and finite element numerical simulation
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作者 Qi-Qiang Ren Li-Fei Li +3 位作者 Jin Wang Rong-Tao Jiang Meng-Ping Li Jian-Wei Feng 《Petroleum Science》 CSCD 2024年第6期3839-3866,共28页
This study aims to elucidate the dynamic evolution mechanism of the fracturing fracture system during the exploration and development of complex oil and gas reservoirs.By integrating methods of rock mechanical testing... This study aims to elucidate the dynamic evolution mechanism of the fracturing fracture system during the exploration and development of complex oil and gas reservoirs.By integrating methods of rock mechanical testing,logging calculation,and seismic inversion technology,we obtained the current insitu stress characteristics of a single well and rock mechanical parameters.Simultaneously,significant controlling factors of rock mechanical properties were analyzed.Subsequently,by coupling hydraulic fracturing physical experiments with finite element numerical simulation,three different fracturing models were configured:single-cluster,double-cluster,and triple-cluster perforations.Combined with acoustic emission technology,the fracture initiation mode and evolution characteristics during the loading process were determined.The results indicate the following findings:(1)The extension direction and length of the fracture are significantly controlled by the direction of the maximum horizontal principal stress.(2)Areas with poor cementation and compactness exhibit complex fracture morphology,prone to generating network fractures.(3)The interlayer development of fracturing fractures is controlled by the strata occurrence.(4)Increasing the displacement of fracturing fluid enlarges the fracturing fracture length and height.This research provides theoretical support and effective guidance for hydraulic fracturing design in tight oil and gas reservoirs. 展开更多
关键词 Rockmechanical parameters Petrophysical experiments Hydraulic fracturing physical experiment Finite element numerical simulation Dynamic evolution mechanism Fracturing fracture
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Teaching Status and Teaching Reform Ideas of Physical Chemistry Experiments for Food Quality and Safety Major
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作者 Bo HOU Jing LIAO 《Agricultural Biotechnology》 2024年第3期45-47,54,共4页
Physical chemistry experiments are an important branch of chemical experiments.In view of problems and shortcomings in physical chemistry experiment teaching of food quality and safety major in Chengdu University,the ... Physical chemistry experiments are an important branch of chemical experiments.In view of problems and shortcomings in physical chemistry experiment teaching of food quality and safety major in Chengdu University,the teaching methods of physical chemistry experiment course of food quality and safety major were explored and practiced,aiming to arouse students enthusiasm for experiments and cultivate their ability of independent learning,comprehensive thinking and independent problem solving. 展开更多
关键词 physical chemistry experiment Food quality SAFETY
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The Design and Implementation of Virtual Physics Experiment System based on VB Programming
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作者 Qingfang Hu 《International Journal of Technology Management》 2015年第1期47-49,共3页
This paper used the virtual reality modeling language (VRML) to establish the 3D virtual experiment instrument model, and by using the visual programming language VB to design and develop a interactive virtual reali... This paper used the virtual reality modeling language (VRML) to establish the 3D virtual experiment instrument model, and by using the visual programming language VB to design and develop a interactive virtual realization experiment platform, the interface has friendly interface, stable operation, strong practicability like with the Windows style, is a kind of reform for the traditional physics experiment teaching mode. The system has practical use value, also has reference value for the reform and modernization of other experimental courses. 展开更多
关键词 physics experiment Computer assisted Instruction CAI courseware VB VRML
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Research on Measures to Cultivate Core Literacy in Senior High School Physics Experiment Teaching
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作者 FENGYuhong 《外文科技期刊数据库(文摘版)教育科学》 2022年第6期181-184,共4页
Physics is a comprehensive, abstract and incomprehensible natural science. Today, with the rapid development of science and technology, the core accomplishment of disciplines has become a topic of concern and discussi... Physics is a comprehensive, abstract and incomprehensible natural science. Today, with the rapid development of science and technology, the core accomplishment of disciplines has become a topic of concern and discussion in various fields of research and teaching. When analyzing the present situation of physics innovation education, it can be found that there is little research on the cultivation of discipline core literacy in our country, and the corresponding theoretical system is lacking. In the process of teaching, teachers should closely combine theory with practice, starting from the core quality of physics, to improve students ability to learn scientific knowledge and skills. This paper puts forward the method of cultivating students core accomplishment from the perspective of physics experiment teaching, hoping to provide reference. 展开更多
关键词 high school physics experiments core competence
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Reform and Practice of University Physics Experimental Teaching Based on OBE Concept
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作者 Yin Si Wei Liu +4 位作者 Xiangyu Song Aixiang Wei Tingguang Bai Lirong Liang Xingbin Xu 《Journal of Contemporary Educational Research》 2024年第10期287-293,共7页
Aiming at the problems of unclear teaching objectives,obsolete content,and single method in the experimental teaching of university physics at our university,we have implemented a series of reform initiatives.It mainl... Aiming at the problems of unclear teaching objectives,obsolete content,and single method in the experimental teaching of university physics at our university,we have implemented a series of reform initiatives.It mainly includes clarifying the student-centered teaching objectives,optimizing the experimental content,innovating the teaching methods,improving the assessment and evaluation system,and improving the experimental conditions[1,2].After the implementation of the reform,the learning effectiveness of students has been significantly improved,the teaching level of teachers has been significantly enhanced,the curriculum system has been optimized,the efficiency of teaching management has been enhanced,and social recognition has been strengthened.Practice shows that the teaching reform based on the outcome-based education concept effectively improves the quality of university physics experimental teaching and lays the foundation for cultivating innovative talents. 展开更多
关键词 Outcome-based education concept University physics experiments Teaching reform EFFICACY
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The Application Strategy of Virtual Simulation Experimental Technology in College Physics Teaching
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作者 MAXinyao 《外文科技期刊数据库(文摘版)教育科学》 2022年第11期077-080,共4页
In the university physics teaching, the application of virtual simulation experiment technology can provide reliable technical support for teachers. If teachers only use the traditional oral teaching method, the teach... In the university physics teaching, the application of virtual simulation experiment technology can provide reliable technical support for teachers. If teachers only use the traditional oral teaching method, the teaching effect is not ideal. Because the physics subject contains many experiments, if students cannot watch the experiment process, students thinking ability and practical ability will be affected. However, under the constraints of teaching conditions, some physics experiments cannot be carried out. With the help of virtual simulation experiment technology, under the virtual simulation experiment, the simulation degree is high and the operation is relatively simple, also has the advantage of safety and risk-free, to compensate for the deficiency of the traditional teaching methods. To a certain extent, also can innovate teaching methods, students can fully observe the physical phenomenon operation process, help students to master the corresponding knowledge. This paper expounds the characteristics of virtual simulation experiment and the application principles of virtual simulation technology in university physics experiment teaching, and proposes the application strategy of this technology. 展开更多
关键词 UNIVERSITY physics teaching virtual simulation experiment technology
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Improvement of Junior High School Physics Experiment Teaching Evaluation System Based on Core Literacy
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作者 RONGDanfang 《外文科技期刊数据库(文摘版)教育科学》 2022年第3期098-102,共5页
According to the current situation of basic physics experiment teaching evaluation and the specific content of basic physics skills, the evaluation system of basic physics experiment teaching is improved to form a new... According to the current situation of basic physics experiment teaching evaluation and the specific content of basic physics skills, the evaluation system of basic physics experiment teaching is improved to form a new 1242 physics experiment teaching evaluation system. 展开更多
关键词 core accomplishment physical experiment teaching teaching evaluation
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Wide angle reflections in OBC seismic physical model experiment
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作者 杨正华 黄翼坚 吴永新 《Applied Geophysics》 SCIE CSCD 2012年第2期207-212,236,共7页
Wide angle acquisition has been taken as a significant measure to obtain high quality seismic data and is getting greater attention, In this paper, we discuss ocean bottom cable (OBC) seismic wide angle reflections ... Wide angle acquisition has been taken as a significant measure to obtain high quality seismic data and is getting greater attention, In this paper, we discuss ocean bottom cable (OBC) seismic wide angle reflections on the basis of a layered model experiment. Some experiment results don't support theoretical conclusions. The main experimental conclusions are: 1. Wide angle reflection energies are stronger than non-wide-angle reflections (up to twice as strong) but there is a big difference between observations and theoretical calculations that suggest the wide angle reflection energies are 15 times the non- wide-angle reflection energy. The reflection energy increases gradually rather than sharply as the theoretical calculations suggest. 2. The reflection events remain hyperbolic when the offset increases. 3. Wide angle reflection dominant frequency is about 20-30% less than non- wide-angle reflections and decreases as the offset increases. The non-wide-angle reflection dominant frequency shows no obvious variation for small offsets. 4. There is no wave shape mutation or polarity reversal near the critical angle. 5. The reflection event group features are the same for both cases of incidence angle greater and less than the critical angle. 6. Direct arrivals, multiples, and water bottom refractions influence the wide angle reflections of the sea floor. 展开更多
关键词 ocean bottom cable physical model wide angle refection model experiment
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MICROGRAVITY EXPERIMENTS OF TWO-PHASE FLOW PATTERNS ABOARD MIR SPACE STATION 被引量:4
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作者 赵建福 解京昌 +1 位作者 林海 胡文瑞 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2001年第2期151-159,共9页
A first experimental study on two-phase how patterns at a long-term, steady microgravity condition was conducted on board the Russian Space Station 'MIR' in August 1999. Carbogal and air are used as the liquid... A first experimental study on two-phase how patterns at a long-term, steady microgravity condition was conducted on board the Russian Space Station 'MIR' in August 1999. Carbogal and air are used as the liquid and the gas phase, respectively. Bubble, slug, slug-annular transitional, and annular hows are observed. A new region of annular how with lower liquid superficial velocity is discovered, and the region of the slug-annular transitional flow is wider than that observed by experiments on board the parabolic aircraft. The main patterns are bubble, slug-annular transitional and annular flows based on the experiments on board MIR space station. Some influences on the two-phase how patterns in the present experiments are discussed. 展开更多
关键词 two-phase flow microgravity fluid physics space experiment
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Analysis on nasal airway by using scale-adaptive simulation combined with standard κ-ω model and 3D printing modeling physical experiment 被引量:2
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作者 Jiemin Zhan Yangyang Xi +2 位作者 Kay Lin Weiguang Yu Wenqing Hu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第4期215-219,I0006,共6页
The physiological structure of the upper respiratory tract is complex and varies with each individual,and the circulating air has turbulent performance.In this paper,based on computed tomography(CT)medical images publ... The physiological structure of the upper respiratory tract is complex and varies with each individual,and the circulating air has turbulent performance.In this paper,based on computed tomography(CT)medical images published online and the three-dimensional(3D)printing technology,a 3D model of the human upper respiratory tract was reconstructed and an experimental device of the upper respiratory tract was made.We implemented the respiratory experiment and measured the flow rate,and a scale-adaptive κ-ω model is applied for numerical simulation,the results are in good agreement.The flow field during respiratory was analyzed by coronal velocity cross section,vortex line and particle tracks.We found that the relatively strong shear effect happens at the areas of nasal valve and nasopharynx.In the middle and upper nasal tract,vortex line separation occurs and there is significant passage effect.The results indicate that SAS method is effective in studying upper respiratory airflow. 展开更多
关键词 3D PRINTER Scale-adaptive SIMULATION Upper RESPIRATORY TRACT physical experiment
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Ethical Dilemma Factor in Regarding Physical Restraints to Elderly of Female Nurses with the Living Together Experience 被引量:2
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作者 Miwa Yamamoto Shizue Mizuno Masako Aota 《International Journal of Clinical Medicine》 2012年第5期328-334,共7页
Purpose: The aim of this study was to illuminate the connotation of “dilemma” regarding the use of physical restraint on elderly patients as represented by female nurses working in general wards at community hospita... Purpose: The aim of this study was to illuminate the connotation of “dilemma” regarding the use of physical restraint on elderly patients as represented by female nurses working in general wards at community hospitals who also live with elderly adults at home. Method: The study used the questionnaire method with an independently prepared questionnaire. Participants: The objective of the study was explained to the persons in charge of nursing in the selected 17 hospitals, and 1929. Finally, this study of participants were 524 female nurses working in general 54 wards (excluding the emergency wards of psychiatry, pediatrics, obstetrics, outpatients, operating rooms, and intensive care units) at community hospitals who also live with elderly adults at home. Results and conclusions: Cronbach’s overall coefficient for the 20 items of dilemma was high (0.78) and the factor analysis extracted four dilemma factors as having a characteristic value of 1 (Kaiser-Meyer-Olkin measure value = 0.81) with a cumulative contribution ratio of 64.5%. The high Cronbach’s for these items (0.86, 0.88, 0.87 and 0.81) confirmed the internal consistencies. With respect to the dilemma where nurses working in general wards at community hospitals who also live with elderly adults at home are faced with the physical restraint of elderly persons, four factors in the clarification of the dilemma were extracted: accomplishment of medical-treatment and accident prevention, characteristic features in nursing for elderly patients with dementia, healthcare professional relationship in nursing for elderly patients with dementia, and priorities on the accident prevention for elderly patients with dementia. Therefore, the construction of four systems to cope with these dilemmas is suggested. These systems would enable practising nurses to: (i) institution of policies to encourage discussion between nurses and other medical staff to reach consensus on treatment;(ii) allocating elderly care specialists to wards to promote alternatives to restraints;(iii) establishment of safety standards to define nurses’ responsibilities;and (iv) institution of continuous ethical education for nurses. 展开更多
关键词 ETHICAL DILEMMA Factor physical RESTRAINT The LIVING Under with ELDERLY People experiENCE
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Three-Dimensional Finite Element Numerical Simulation and Physical Experiment for Magnetism-Stress Detecting in Oil Casing 被引量:2
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作者 MENG Fanshun ZHANG Jie +2 位作者 YANG Chaoqun YU Weizhe CHEN Yuxi 《Journal of Ocean University of China》 SCIE CAS 2015年第4期669-674,共6页
The casing damage has been a big problem in oilfield production. The current detection methods mostly are used after casing damage, which is not very effective. With the rapid development of China's offshore oil i... The casing damage has been a big problem in oilfield production. The current detection methods mostly are used after casing damage, which is not very effective. With the rapid development of China's offshore oil industry, the number of offshore oil wells is becoming larger and larger. Because the cost of offshore oil well is very high, the casing damage will cause huge economic losses. What's more, it can also bring serious pollution to marine environment. So the effective methods of detecting casing damage are required badly. The accumulation of stress is the main reason for the casing damage. Magnetic anisotropy technique based on counter magnetostriction effect can detect the stress of casing in real time and help us to find out the hidden dangers in time. It is essential for us to prevent the casing damage from occurring. However, such technique is still in the development stage. Previous studies mostly got the relationship between stress and magnetic signals by physical experiment, and the study of physical mechanism in relative magnetic permeability connecting the stress and magnetic signals is rarely reported. The present paper uses the ANSYS to do the three-dimensional finite element numerical simulation to study how the relative magnetic permeability works for the oil casing model. We find that the quantitative relationship between the stress' s variation and magnetic induction intensity's variation is: Δδ =K* ΔB, K = 8.04×109, which is proved correct by physical experiment. 展开更多
关键词 oil casing damage magnetism-stress detecting magnetic anisotropy finite element analysis physical experiment relative magnetic permeability ANSYS three-dimensional numerical simulation
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A 5.12-GHz LC-based phase-locked loop for silicon pixel readouts of high-energy physics 被引量:1
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作者 Xiao-Ting Li Wei Wei +3 位作者 Ying Zhang Xiong-Bo Yan Xiao-Shan Jiang Ping Yang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第7期49-59,共11页
There is an urgent need for high-quality and high-frequency clock generators for high-energy physics experiments.The transmission data rate exceeds 10 Gbps for a single channel in future readout electronics of silicon... There is an urgent need for high-quality and high-frequency clock generators for high-energy physics experiments.The transmission data rate exceeds 10 Gbps for a single channel in future readout electronics of silicon pixel detectors.Others,such as time measurement detectors,require a high time resolution based on the time-to-digital readout architecture.A phase-locked loop(PLL)is an essential and broadly used circuit in these applications.This study presents an application-specific integrated circuit of a low-jitter,low-power LC-tank that is PLL fabricated using 55-nm CMOS technology.It includes a 3rd-order frequency synthesis loop with a programmable bandwidth,a divide-by-2 pre-scaler,standard low-voltage differential signaling interfaces,and a current mode logic(CML)driver for clock transmissions.All the d-flip-flop dividers and phase-frequency detectors are protected from single-event upsets using the triple modular redundancy technique.The proposed VCO uses low-pass filters to suppress the noise from bias circuits.The tested LC-PLL covers a frequency locking range between 4.74 GHz and 5.92 GHz with two sub-bands.The jitter measurements of the frequency-halved clock(2.56 GHz)are less than 460 fs and 0.8 ps for the random and deterministic jitters,respectively,and a total of 7.5 ps peak-to-peak with a bit error rate of 10^(-12).The random and total jitter values for frequencies of 426 MHz and 20 MHz are less than 1.8 ps and 65 ps,respectively.The LC-PLL consumed 27 mW for the core and 73.8 mW in total.The measured results nearly coincided with the simulations and validated the analyses and tests. 展开更多
关键词 LC phase-locked loop Analog electronic circuits Front-end electronics for detector readout High-energy physics experiments
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JET and the Physics Basis of ITER
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作者 Martin Keilhacker 《Plasma Science and Technology》 SCIE EI CAS CSCD 2004年第1期2109-2122,共14页
JET has made unique contributions to the physics basis of ITER by virtue ofits ITER-like geometry, large plasma size and D-T capability. The paper discusses recent JET resultsand their implications for ITER in the are... JET has made unique contributions to the physics basis of ITER by virtue ofits ITER-like geometry, large plasma size and D-T capability. The paper discusses recent JET resultsand their implications for ITER in the areas of standard ELMy H-mode, D-T operation and advancedtokamak modes. In ELMy H-mode the separation of plasma energy into core and pedestal contributionsshows that core confinement scales like gyroBohm transport. High triangularity has a beneficialeffect on confinement and leads to an integrated plasma performance exceeding the ITER Q =10reference case. A revised type I ELM scaling predicts acceptable ELM energy losses for ITER, whileprogress in physics understanding of NTMs shows how to control them in ITER. The D-T experiments of1997 have validated ICRF scenarios for heating ITER/a reactor and identified ion minority schemes(e.g. (~3He)DT) with strong ion heating. They also show that the slowing down of alpha particles isclassical so that the self-heating by fusion alphas should cause no unexpected problems. With thePellet Enhanced Performance mode of 1988, JET has produced the first advanced tokamak mode, withpeaked pressure profiles sustained by reversed magnetic shear and strongly reduced transport. Morerecently, LHCD has provided easy tuning of reversed shear and reliable access to ITBs. Improvedphysics understanding shows that rational g-surfaces play a key role in the formation anddevelopment of ITBs. The demonstration of real time feedback control of plasma current and pressureprofiles opens the path towards fully controlled steady-state tokamak plasmas. 展开更多
关键词 fusion experiment JET high confinement regime ELMy H-mode advanced tokamakscenario D-T experiments physics basis of ITER
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