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善于将“倒逼”机制转化为“主动”机制——运用经济规律的辩证法 被引量:1
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作者 杨承训 《海派经济学》 CSSCI 2012年第3期17-28,共12页
中国特色社会主义道路体现了中国发展的根本规律,而它在进程中的一些阶段、环节和经济单元还有很多具体经济规律未被认识和遵循,有时处于矛盾交织的被动局面,形成"倒逼"态势,但它促使人们深化认识和运用马克思主义方法,认真... 中国特色社会主义道路体现了中国发展的根本规律,而它在进程中的一些阶段、环节和经济单元还有很多具体经济规律未被认识和遵循,有时处于矛盾交织的被动局面,形成"倒逼"态势,但它促使人们深化认识和运用马克思主义方法,认真总结、调查研究,揭示和掌握规律,变被动为主动,开拓新局面。基于主客观、国内外多种复杂的因素,这种"倒逼"机制将会常态化,需要充分利用社会主义制度优势建立和完善变"倒逼"为"主动"的长效机制。文章从分析现实的三个矛盾现象入手,试图揭示背后的规律性,并对构建将"倒逼"机制转化为"主动"的长效机制提出一些看法。 展开更多
关键词 “倒逼”态势 客观经济规律 “主动”机制 长效机制
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Setting up the Model of Xeno-graft Verse Host Disease
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作者 夏国伟 张元芳 丁强 《Journal of Nanjing Medical University》 2004年第1期32-35,共4页
Objective: To observe human to mouse one way mixed lymphocyte(MLC); And to set up the xeno-grats verse host disease Xeno-graft host disease(XGVHD) model,probing its immunologic mechamism.Methods: Mouse splenic lympho... Objective: To observe human to mouse one way mixed lymphocyte(MLC); And to set up the xeno-grats verse host disease Xeno-graft host disease(XGVHD) model,probing its immunologic mechamism.Methods: Mouse splenic lymphocyte were collected in asepsis and treated by mitomycin as activating cell. Human Peripheral blood lymphocytes (hPBL)were separated and gathered as reacting cell; Mouse splenic lymphocyte and hPBL were mixed to incubate for a week. Destroying recipient (mouse) immune system by total body irradiation (TBI) and intraperitoneal injecting CTX、MTX; Separating and collecting hPBL; Injecting hPBL to mouse by caudal vein. Results; ①HPBL in the experiment groups(mixed mouse lymphocyte) proliferated obviously, the amount of 3H-TdR in corporation increased evidently(P<0.05); The mean percentage of CD 4、CD 8、IgG 、IgM positive cells rose markedly. ②Experiment groups,the hPBL were found in the spleen and kidney tissue, fas protein expressing, we occasionally discovered and apoptosis cells.Conclusion: The human to mouse one-way MLC has obvious lymphocyte proliferation. By these means,we succeed in inducing XGVHD and setting up a XGVHD model. 展开更多
关键词 senograft one-way mixed lymphocyte Xeno-graft host disease total body irradiation
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齿轮耦合的转子-轴承系统非线性动力特性的研究 被引量:31
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作者 张锁怀 李忆平 丘大谋 《机械工程学报》 EI CAS CSCD 北大核心 2001年第9期53-57,61,共6页
在考虑齿轮时变啮合刚度、齿侧间隙、脱齿、挤齿及齿背接触 等因素的情况下,建立了齿轮耦合的转子—滑动轴承系统的多自由度动力学模型。用数值方 法研究了该系统的质量不平衡响应,结果发现,由于齿轮时变啮合刚度的影响,随着转速的... 在考虑齿轮时变啮合刚度、齿侧间隙、脱齿、挤齿及齿背接触 等因素的情况下,建立了齿轮耦合的转子—滑动轴承系统的多自由度动力学模型。用数值方 法研究了该系统的质量不平衡响应,结果发现,由于齿轮时变啮合刚度的影响,随着转速的 增加,系统动力学响应首先由周期运动向准周期运动变化,当转速超过某一值时,系统的响应将由准周期运动发展为混沌运动;由于混沌运动,转子将沿齿轮中心线方向产生很大的变 形,脱齿、齿背接触及挤齿现象也将发生,可能导致系统产生破坏。 展开更多
关键词 齿侧间隙 时变啮合刚度 分岔 混沌 非线性动力学 齿轮耦合 转子-轴承系统
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Optimal design method for force in vibration control of multi-body system with quick startup and brake 被引量:3
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作者 唐华平 彭娅清 《Journal of Central South University of Technology》 EI 2005年第4期459-464,共6页
A kind of active vibration control method was presented through optimal design of driving load of multi-body system with quick startup and brake. Dynamical equation of multi-body system with quick startup and brake wa... A kind of active vibration control method was presented through optimal design of driving load of multi-body system with quick startup and brake. Dynamical equation of multi-body system with quick startup and brake was built, and mathematical model of representing vibration control was also set up according to the moving process from startup to brake. Then optimization vibration control model of system driving load was founded by applying theory of optimization control, which takes rigid body moving variable of braking moment as the known condition, and vibration control equation of multi-body system with quick startup and brake was converted into boundary value problem of differential equation. The transient control algorithm of vibration was put forward, which is the analysis basis for the further research. Theoretical analysis and calculation of numerical examples show that the optimal design method for the multi-body system driving load can decrease the vibration of system with duplication. 展开更多
关键词 vibrationl multi-body system active control
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Aortic stenosis: insights on pathogenesis and clinical implications 被引量:3
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作者 Patrizia Carita Giuseppe Coppola +8 位作者 Giuseppina Novo Giuseppa Caccamo Marco Guglielmo FabioBalasus Salvatore Novo Sebastiano Castrovinci Marco Moscarelli Khalil Fattouch Egle Corrado 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第6期489-498,共10页
Aortic stenosis (AS) is a common valvular heart disease in the Western populations, with an estimated overall prevalence of 3% in adults over 75 years. To understand its patho-biological processes represents a prior... Aortic stenosis (AS) is a common valvular heart disease in the Western populations, with an estimated overall prevalence of 3% in adults over 75 years. To understand its patho-biological processes represents a priority. In elderly patients, AS usually involves trileaflet valves and is referred to as degenerative calcific processes. Scientific evidence suggests the involvement of an active "atherosclerosis-like" pathogenesis in the initiation phase of degenerative AS. To the contrary, the progression could be driven by different forces (such as mechanical stress, genetic factors and interaction between inflammation and calcification). The improved understanding presents potentially new therapeutic targets for preventing and inhibiting the development and progression of the disease. Furthermore, in clinical practice the management of AS patients implies the evaluation of generalized atherosclerotic manifestations (i.e., in the coronary and carotid arteries) even for prognostic reasons. In counselling elderly patients, the risk stratification should address individual frailty beyond the generic risk scores. In these regard, the co-morbidities, and in particular those linked to the global atherosclerotic burden, should be carefully investigated in order to define the risk/benefit ratio for invasive treatment strategies. We present a detailed overview of insights in pathogenesis of AS with possible practical implications. 展开更多
关键词 ATHEROSCLEROSIS Clinical implications Degenerative aortic stenosis PATHOGENESIS The elderly
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Control Strategies and Mechanisms for Active Control of Sound Transmission into a Vibro-acoustic Enclosure
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作者 靳国永 冯娜 杨铁军 《Journal of Marine Science and Application》 2011年第2期206-214,共9页
An analytical study was presented on active control of sound transmission into a vibro-acoustic enclosure comprising two flexible plates. Two types of actuators were used, i.e. acoustic actuator and distributed lead z... An analytical study was presented on active control of sound transmission into a vibro-acoustic enclosure comprising two flexible plates. Two types of actuators were used, i.e. acoustic actuator and distributed lead zirconate titanate piezoelectric (PZT) actuator instead of point force actuator. Using the modal acoustic transfer impedance-mobility matrices, the excitation and interaction in the coupled sound transmission system can be described with clear physical significance. With the control system designed to globally reduce the sound field, different control system configurations were considered, including the structural actuator on the incident plate, actuator on the receiving plate, acoustic actuator on the cavity, and their combinations. The effectiveness and performance of the control strategy corresponding to each system configuration were compared and discussed. The role and control mechanism of each type of actuator were of particular interest. It was shown that the incident plate actuator is effective in controlling the cavity-dominated modes and the structural modes dominated by the incident plate and receiving plate. Two main control mechanisms are involved in this control configuration, i.e., modal suppressing and modal rearrangement. For control system configuration with only acoustic actuator in the enclosure, the mechanism involved in this arrangement is purely modal suppression. Desirable placements of structural actuators in terms of total potential energy reduction were also discussed. 展开更多
关键词 sound transmission active control control mechanism ENCLOSURE piezoelectric (PZT) actuators
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Improved Behaviour Control on Laser Cruise of Autonomous Mobile Robot 被引量:1
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作者 张国伟 丁永生 卢秋红 《Journal of Donghua University(English Edition)》 EI CAS 2013年第6期482-486,共5页
The software of behaviour-based algorithm~ was parted to several functional modules which represented different behaviours with different priorities. A basic algorithm with S-type arbiter and an improved algorithm wit... The software of behaviour-based algorithm~ was parted to several functional modules which represented different behaviours with different priorities. A basic algorithm with S-type arbiter and an improved algorithm with I-type arbiter were compared. The improved algorithm can reduce judging time and avoid some mistakes of the basic one. In mapping obstacles, the robot adjusted the spread angle according to different distances to obstacles in scaled vector field histogram (SVFH) algorithm, and then the robot turned more sharply in near obstacles than in far obstacles, which made the robot move more safely and smoothly in a cluttered room. 展开更多
关键词 mobile robot behaviour control laser cruise vector field histogram (VFH)
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A disc-type magneto-rheologic fluid damper 被引量:3
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作者 祝长生 《Journal of Zhejiang University Science》 CSCD 2003年第5期514-519,共6页
A disc-type magneto-rheological fluid damper operating in shear mode is proposed in this paper,which is based on the special characteristics of the magneto-rheological (MR) fluid with rapid, reversible and dramatic ch... A disc-type magneto-rheological fluid damper operating in shear mode is proposed in this paper,which is based on the special characteristics of the magneto-rheological (MR) fluid with rapid, reversible and dramatic change in its rheological properties by the application of an external magnetic field. The magneticfield of the disc-type MR fluid damper is analysed by the finite element method ; the controllability of the disctype MR fluid damper on the dynamic behaviour of a rotor system ; and the effectiveness of the disc-type MR fluid damper in controlling the vibration of a rotor system, are studied in a flexible rotor system with an over-hung disc. It is shown that the magnetic flux density of the disc-type MR fluid damper in the working areas can significantly change with the applied current in the coil ; and that the dynamic behavior of the disc-type MR fluid damper can be varied by the application of an external magnetic field produced by a low voltage electromagnetic coil. The disc-type MR fluid damper can significantly change the dynamic characteristics of a rotor system, provided that the location of the disk-type MR fluid damper is carefully chosen. The disc-type MR fluid damper is a new actuator with good dynamic characteristics for rotating machinery. 展开更多
关键词 Magneto-rheological fluid DAMPER ROTORDYNAMICS Vibr ation Active vibration control
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Beginning of a New Revolution of Science & Technology 被引量:5
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作者 Jinzhong Yan 《Journal of Physical Science and Application》 2014年第4期269-275,共7页
Modern science and technology is being developed towards destroying human and human calls for a new era of science & technology. Contemporary science is seeing a significant breakthrough and a new revolution of scien... Modern science and technology is being developed towards destroying human and human calls for a new era of science & technology. Contemporary science is seeing a significant breakthrough and a new revolution of science and technology is beginning. The theoretical basis of the new revolution of science and technology is "state space-time", "the unity of physics and biology", "thinking motion and automatic organization of the universe" and "thinking's active control". The new revolution of science and technology takes material (microscopic particle) science, life (organic and inorganic life) science and thinking science as the fundamental sciences, takes life technology, new information technology, new material technology and new energy technology as the basis of the overall technological system, progresses in all aspects, including life technology, medicine, new material technology, new information technology, new energy technology, new robot technology, new manufacturing technology, laser technology, astronavigation technology, ocean technology, military technology, new educational technology, etc., and at the same time Qigong technology with thinking control as its core will emerge. In the era of life, thinking and Qigong technology, technology proceeds very rapidly, global society and economy develop at a high speed, and globalization is accelerated. Life, thinking and Qigong technologies feature improvement of human internal energy and quality, purify human soul, reduce material desire, and greatly reduce environmental disruption. The overall (thinking and Qigong) technology takes the establishment of the cosmic era of human as its ultimate goal. 展开更多
关键词 New revolution of science and technology life technology thinking technology Qigong technology beginning.
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Evaluation and Optimization of the Mixed Redundancy Strategy in Cloud-Based Systems
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作者 Pan He Xueliang Zhao +2 位作者 Chun Tan Zhihao Zheng Yue Yuan 《China Communications》 SCIE CSCD 2016年第9期237-248,共12页
Mixed redundancy strategies are generally used in cloud-based systems,with different node switch mechanisms from traditional fault-tolerant strategies.Existing studies often concentrate on optimizing a single strategy... Mixed redundancy strategies are generally used in cloud-based systems,with different node switch mechanisms from traditional fault-tolerant strategies.Existing studies often concentrate on optimizing a single strategy in cloud computing environment and ignore the impact of mixed redundancy strategies.Therefore,a model is proposed to evaluate and optimize the reliability and performance of cloud-based degraded systems subject to a mixed active and cold standby redundancy strategy.In this strategy,node switching is triggered by a continual monitoring and detection mechanism when active nodes fail.To evaluate the transient availability and the expected job completion rate of systems with such kind of strategy,a continuous-time Markov chain model is built on the state transition process and a numerical method is used to solve the model.To choose the optimal redundancy for the mixed strategy under system constraints,a greedy search algorithm is proposed after sensitivity analysis.Illustrative examples were presented to explain the process of calculating the transient probability of each system state and in turn,the availability and performance of the whole system.It was shown that the near-optimal redundancy solution could be obtained using the optimizationmethod.The comparison with optimization of the traditional mixed redundancy strategy proved that the system behavior was different using different kinds of mixed strategies and less redundancy was assigned for the new type of mixed strategy under the same system constraint. 展开更多
关键词 Mixed redundancy strategy MONITORING reliability analysis Markov chain cloud-based system
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Optimized transmission coordination mechanisms for opportunistic routing
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作者 Chen Wei Qin Zhiguang Liu Qiao Jin Jing 《High Technology Letters》 EI CAS 2011年第3期236-244,共9页
The successful rate of transmission coordination of opportunistic routing (OK) is analyzea systematically, and then two efficient transmission coordination mechanisms (TCMs) are proposed for OR: a batch sliding w... The successful rate of transmission coordination of opportunistic routing (OK) is analyzea systematically, and then two efficient transmission coordination mechanisms (TCMs) are proposed for OR: a batch sliding window-based TCM and a bit map-based TCM, to reduce the total number of packet transmissions and improve end-to-end throughput for OR. The batch sliding window-based TCM avoids the oscillation of the successful rate of transmission coordination by transmitting packets in continuous batch mode so as to improve the average successful rate of transmission coordination efficiently, while the bit map-based TCM improves end-to-end throughput of OR by reducing the overhead of transmission coordination. Exhaustive simulations show that the average end-to-end throughput gains of the two proposed TCMs are 15.4% and 6.4% over the batch map-based TCM, respectively. 展开更多
关键词 opportunistic routing (OR) batch sliding window transmission coordination multi-hop wireless networks bit map
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Integrated yaw and rollover control based on differential braking for off-road vehicles with mechanical elastic wheel 被引量:1
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作者 LI Hai-qing ZHAO You-qun +1 位作者 LIN Fen XIAO Zhen 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第9期2354-2367,共14页
Aiming at the issue of yaw and rollover stability control for off-road vehicles with non-pneumatic mechanical elastic wheel(MEW),an integrated control system based on fuzzy differential braking is developed.By simplif... Aiming at the issue of yaw and rollover stability control for off-road vehicles with non-pneumatic mechanical elastic wheel(MEW),an integrated control system based on fuzzy differential braking is developed.By simplifying the structure of the MEW,a corresponding fitting brush tire model is constructed and its longitudinal and lateral tire force expressions are set up,respectively.Then,a nonlinear vehicle simulation model with MEW is established to validate the proposed control scheme based on Carsim.The designed yaw and rollover control system is a two-level structure with the upper additional moment controller,which utilizes a predictive load transfer ratio(PLTR)as the rollover index.In order to design the upper integrated control algorithm,fuzzy proportional-integral-derivative(PID)is adopted to coordinate the yaw and rollover control,simultaneously.And the lower control allocator realizes the additional moment to the vehicle by differential braking.Finally,a Carsim-simulink co-simulation model is constructed,and simulation results show that the integrated control system could improve the vehicle yaw and roll stability,and prevent rollover happening. 展开更多
关键词 integrated control rollover stability yaw stability active braking fuzzy control CO-SIMULATION mechanical elastic wheel
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Development of Independent Moving Puppet Robot
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作者 Byeong-yeol KIM Hwan-ik CHUNG Hern-soo HAHN 《Journal of Measurement Science and Instrumentation》 CAS 2010年第4期364-367,共4页
This paper is about the automation of the marionette performance. A method to solve the problem on the mobility of the automated marionette performance is proposed. Since it is difficult to control the marionette by h... This paper is about the automation of the marionette performance. A method to solve the problem on the mobility of the automated marionette performance is proposed. Since it is difficult to control the marionette by hands, as an alternative, the automated marionette is studied. However, the automtic marionette performance is limited in the silence and mobility. Therefore, an independent shifter to move freely on the stage is required. The magnetic device which connects the movable robot and the marionette controlling robot is conceived. The magnetic device is improved and applied by considering the features of the marionette robot, which is the irregular movement of the marionette controller and of the parallel limited area. The burden of being trapped on the magnet is minimized by dividing the robot to the upper and lower parts of the marionette performance stage. The direction of the magnet is considered to make the mobile robot to move freely. Thus, the efficiency and safety of the device is confirmed by balancing the strength with the permanent magnet. 展开更多
关键词 MARIONETTE MAGNET mobile robot PUPPET
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A Potential Flow Based Flight Simulator for an Underwater Glider 被引量:3
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作者 Surasak Phoemsapthawee Marc Le Boulluec +1 位作者 Jean-Marc Laurens Fran ois Deniset 《Journal of Marine Science and Application》 2013年第1期112-121,共10页
Underwater gliders are recent innovative types of autonomous underwater vehicles (AUVs) used in ocean exploration and observation. They adjust their buoyancy to dive and to return to the ocean surface. During the ch... Underwater gliders are recent innovative types of autonomous underwater vehicles (AUVs) used in ocean exploration and observation. They adjust their buoyancy to dive and to return to the ocean surface. During the change of altitude, they use the hydrodynamic forces developed by their wings to move forward. Their flights are controlled by changing the position of their centers of gravity and their buoyancy to adjust their trim and heel angles. For better flight control, the understanding of the hydrodynamic behavior and the flight mechanics of the underwater glider is necessary. A 6-DOF motion simulator is coupled with an unsteady potential flow model for this purpose. In some specific cases, the numerical study demonstrates that an inappropriate stabilizer dimension can cause counter-steering behavior. The simulator can be used to improve the automatic flight control. It can also be used for the hydrodynamic design optimization of the devices. 展开更多
关键词 underwater glider potential flow Newton-Euler equation autonomous underwater vehicles (AUVs) flight simulator
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A Novel Floodless Service Discovery Mechanism Designed for Software-Defined Networking
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作者 WANG Jian HUANG Tao LIU Jiang LIU Yunjie 《China Communications》 SCIE CSCD 2014年第2期12-25,共14页
The low-cost,self-configuration capability and "plug-and-play" feature of Ethernet establishes its dominant position in the local area networks(LAN).However,it is hard to extend to large scale because of the... The low-cost,self-configuration capability and "plug-and-play" feature of Ethernet establishes its dominant position in the local area networks(LAN).However,it is hard to extend to large scale because of the legacy broadcast-based service discovery mechanism.Therefore,to solve this problem,a new split network architecture named Software-Defined Networking(SDN) is introduced in this paper,and a novel floodless service discovery mechanism(FSDM)for SDN is designed.For the FSDM,the widespread broadcast messages for Dynamic Host Configuration Protocol(DHCP) and Address Resolution Protocol(ARP) are considered especially,respectively.Then the DHCP relay and ARP proxy are proposed to handle DHCP broadcast messages and ARP broadcast messages,respectively.The proposed FSDM in this paper can eliminate flooding completely,reserve the autoconfiguration characteristics.Particularly,there is no need to change the existing hardware,software and protocols of hosts for the proposed scheme.Finally,the simulation results are demonstrated to show that our proposed model allows redundant links existed in network and has the property of scalability,which can significantly reduce network traffic in data plane and control traffic in control plane,and decrease the overhead of control plane. 展开更多
关键词 Software-Defined Networking FLOODING DHCP ARP
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Osteoporosis as A Source of Tissue Mineralization Research on Osteoporosis Therapy and Dissolution of Arterial Mineralization
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作者 Maciej Pawlikowski 《Journal of Life Sciences》 2014年第7期610-625,共16页
Based on research conducted by the author in the last thirty-five years, this article presents the physicochemical mechanisms of the osteoporosis process, transport of substances created as its result, and the phenome... Based on research conducted by the author in the last thirty-five years, this article presents the physicochemical mechanisms of the osteoporosis process, transport of substances created as its result, and the phenomena of tissue mineralization resulting from osteoporosis. Examination of bones, joint cartilage, arteries, veins, parts of heart, thyroid, salivary glands, various tumors and others was conducted with the use of biological and polarizing microscopy, SEM, EDS, ASA, IR, Raman spectroscopy, and X-ray diffraction. Several devices of the same kind, e.g. different types of SEM, were used. Specimens used for examination were obtained from post-surgery and post rnortem materials. Examination of human bones focused on their mineralization and demineralization (osteoporosis). Examination of the mineralization of other tissues was conducted in terms of the ageing of human body. Obtained results show that the process of osteoporosis leads not just to mechanical degradation of bones, but through the transport of ions (mainly Ca and P), it also causes mineralization of soft tissue. Such mineralization occurs in mineralization centers that have been classified in regard to genetics. Tissue mineralization in its first stage is latent and consists of including atoms, mainly Ca and P, into the biological structures of compounds that build the tissues. Latent mineralization may evolve into the next stage--apparent mineralization. Both types of mineralization cause many health issues and may lead to death. This article also presents initial results of research on dissolution of aortic mineralization. 展开更多
关键词 Human osteoporosis physicochemical processes tissue mineralization
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Advanced flow measurement and active flow control of aircraft with MEMS
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作者 Jiang Chengyu Deng Jinjun +1 位作者 Ma Binghe Yuan Weizheng 《Engineering Sciences》 EI 2012年第5期26-32,共7页
Advanced flow measurement and active flow control need the development of new type devices and systems.Micro-electro-mechanical systems(MEMS) technologies become the important and feasible approach for micro transduce... Advanced flow measurement and active flow control need the development of new type devices and systems.Micro-electro-mechanical systems(MEMS) technologies become the important and feasible approach for micro transducers fabrication.This paper introduces research works of MEMS/NEMS Lab in flow measurement sensors and active flow control actuators.Micro sensors include the flexible thermal sensor array,capacitive shear stress sensor and high sensitivity pressure sensor.Micro actuators are the balloon actuator and synthetic jet actuator respectively.Through wind tunnel test,these micro transducers achieve the goals of shear stress and pressure distribution measurement,boundary layer separation control,lift enhancement,etc.And unmanned aerial vehicle(UAV) flight test verifies the ability of maneuver control of micro actuator.In the future work,micro sensor and actuator can be combined into a closed-loop control system to construct aerodynamic smart skin system for aircraft. 展开更多
关键词 MEMS flow measurement active flow control smart skin
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Experimental Study of Improved HAWT Performance in Simulated Natural Wind by an Active Controlled Multi-Fan Wind Tunnel 被引量:2
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作者 Kazuhiko Toshimitsu Takahiko Narihara +2 位作者 Hironori Kikugawa Arata Akiyoshi Yuuya Kawazu 《Journal of Thermal Science》 SCIE EI CAS CSCD 2017年第2期113-118,共6页
The effects of turbulent intensity and vortex scale of simulated natural wind on performance of a horizontal axis wind turbine(HAWT) are mainly investigated in this paper. In particular, the unsteadiness and turbulenc... The effects of turbulent intensity and vortex scale of simulated natural wind on performance of a horizontal axis wind turbine(HAWT) are mainly investigated in this paper. In particular, the unsteadiness and turbulence of wind in Japan are stronger than ones in Europe and North America in general. Hence, Japanese engineers should take account of the velocity unsteadiness of natural wind at installed open-air location to design a higher performance wind turbine. Using the originally designed five wind turbines on the basis of NACA and MEL blades, the dependencies of the wind frequency and vortex scale of the simulated natural wind are presented. As the results, the power coefficient of the newly designed MEL3-type rotor in the simulated natural wind is 130% larger than one in steady wind. 展开更多
关键词 Wind Turbine Wind Energy Natural Wind Unsteady Flow Rotor Design TURBULENCE
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Review of actuators for high speed active flow control 被引量:22
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作者 WANG Lin LUO ZhenBing +2 位作者 XIA ZhiXun LIU Bing DENG Xiong 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第8期2225-2240,共16页
Actuators are one of the key points for the development of active flow control technology.Efficient methods of high speed flow control can provide enhanced propulsive efficiency and at the same time enable safe and ma... Actuators are one of the key points for the development of active flow control technology.Efficient methods of high speed flow control can provide enhanced propulsive efficiency and at the same time enable safe and maneuverable high speed flight.The development of high speed flight technology promotes the emergence of novel and robust actuators.This review introduces the state of the art in the development of actuators that can be used in high speed active flow control.The classification and different operation criteria of the actuators are discussed.The specifications,mechanisms and applications of various popular actuator types including fluidic,mechanical,and plasma actuators are described.Based on the realistic need of high speed flow control and the existing results of actuators,a new actuator design method is proposed.At last,the merits and drawbacks of the actuators are summarized and some suggestions on the development of active flow control technology are put forward. 展开更多
关键词 active flow control actuators figure of merit fluidic MECHANICAL PLASMA
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Coherent structures in wall turbulence and mechanism for drag reduction control 被引量:6
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作者 XU ChunXiao DENG BingQing +1 位作者 HUANG WeiXi CUI GuiXiang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第6期1053-1061,共9页
Herein is introduced the mechanism for active control influencing the generation of the near-wall streamwise vortices,which are closely related to the production of high skin friction in wall-bounded turbulent flows.A... Herein is introduced the mechanism for active control influencing the generation of the near-wall streamwise vortices,which are closely related to the production of high skin friction in wall-bounded turbulent flows.A new opposition control scheme with adjusting control amplitude is proposed and evaluated in turbulent channel flow by direct numerical simulations.The maximum drag reduction rate can be greatly enhanced by the strengthened control.Finally the effectiveness of the control to the coherent structures at high Reynolds numbers is investigated by using a linear transient growth model. 展开更多
关键词 wall turbulence coherent structure drag reduction active control
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