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思想政治教育能动体探析 被引量:4
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作者 周桂萍 《广西社会科学》 2007年第5期190-193,共4页
把思想政治教育的一般主体和客体提升为能动主体和能动客体(合称为能动体)是现代思想政治教育理论创新与实践发展的客观要求。能动体包含能动认知、能动情感、能动意志、能动信念和能动行为等内在要素,并构成自知、自主、自由等不同的... 把思想政治教育的一般主体和客体提升为能动主体和能动客体(合称为能动体)是现代思想政治教育理论创新与实践发展的客观要求。能动体包含能动认知、能动情感、能动意志、能动信念和能动行为等内在要素,并构成自知、自主、自由等不同的发展层次,具有能动性与受动性、主体性和客体性、辩证的思维方式等特点,能够发挥积极预见、理性激励和有效协调等功能。 展开更多
关键词 思想政治教育能动体 内涵 结构 特点 功能
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超越“结构-行为体”的二元分析——1980-1999年天津市政府投资政策及实践分析
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作者 邱红艳 《华中师范大学学报(人文社会科学版)》 CSSCI 北大核心 2005年第1期104-110,共7页
本研究希望透过分析中央政府和天津市政府在天津经济发展中作用这一问题 ,参与探讨如何解画结构与行为体能动性间辩证关系的讨论。通过对在天津市利用外资和城市基础设施建设内实践形成的过程中天津市政府和中央政府影响的分析 ,发现天... 本研究希望透过分析中央政府和天津市政府在天津经济发展中作用这一问题 ,参与探讨如何解画结构与行为体能动性间辩证关系的讨论。通过对在天津市利用外资和城市基础设施建设内实践形成的过程中天津市政府和中央政府影响的分析 ,发现天津市选择既重视经济发展又关注民生的发展方式 ,是在中央政府和天津市政府共同作用的结果。在这个过程中 ,虽然中央政府对天津市政府的影响很重要 ,但不容忽视的是 ,天津市政府是在对中央政府的利益偏好进行评估和解释基础上提出了自己的策略选择。而且尽管他们之间的利益偏好比较接近 ,但他们仍然存在相互作用 ,各自有自主行为的空间 ,其行为选择同样可能存在差异。这种差异可能导致矛盾与冲突 ,也同样可能带来合作。至于结果究竟导致合作还是矛盾 ,又是如何形成的 ,端赖于对行为体间互动过程的“历史细节”的详尽挖掘。这是全面呈现“结构 -行为体能动性”间辩证关系的关键。 展开更多
关键词 结构限制 行为能动 “细节” 中央与地方相互作用 地方自主意识 策略选择
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蠕动插入式内窥镜机器人的研究 被引量:4
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作者 林良明 张江安 宋一然 《中国医疗器械杂志》 CAS 2001年第1期45-47,35,共4页
论述国外内窥镜机器人系统的组成、移动机构的模型和蠕动式机器人的应用研究 ,将为最小创伤性外科手术提供一种崭新的手段 。
关键词 内窥镜 蠕动式能动体 内窥镜机器人 微型机器人 创伤外科 临床应用
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教育活动要素及其层次结构探析 被引量:2
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作者 袁祖荣 《重庆教育学院学报》 2001年第2期70-74,共5页
教育者和教育对象属于人的要素 ,可分别充当教育活动的主体和能动客体 ,而教育内容则是纯粹客体。明确提出并分清能动客体和纯粹客体 ,初步分析主体要素的层次结构 ,着力研究教育活动的关系层次结构及其认识论意义 ,对整个教育活动系统... 教育者和教育对象属于人的要素 ,可分别充当教育活动的主体和能动客体 ,而教育内容则是纯粹客体。明确提出并分清能动客体和纯粹客体 ,初步分析主体要素的层次结构 ,着力研究教育活动的关系层次结构及其认识论意义 ,对整个教育活动系统的完整认识有重要意义。 展开更多
关键词 能动 纯粹客 层次 关系层次 教育活动 教育者 教育对象 层次结构 构成要素
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Kinetics of cerium(Ⅳ) and fluoride extraction from sulfuric solutions using bifunctional ionic liquid extractant(Bif-ILE)[A336][P204] 被引量:7
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作者 杨华玲 陈继 +3 位作者 张冬丽 王威 崔红敏 刘郁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1937-1945,共9页
The extraction kinetics of Ce(Ⅳ) and Ce(Ⅳ)-F^- mixture systems from sulfuric solutions to n-heptane solution containing Bif-ILE[A336][P204]([trialkylmethylammonium][di-2-ethylhewanxylphosphinate]) with a const... The extraction kinetics of Ce(Ⅳ) and Ce(Ⅳ)-F^- mixture systems from sulfuric solutions to n-heptane solution containing Bif-ILE[A336][P204]([trialkylmethylammonium][di-2-ethylhewanxylphosphinate]) with a constant interfacial area cell with laminar flow were studied,just to elucidate the extraction mechanism and the mass transfer models.The data were analyzed in terms of pseudo-first-order constants.The effects of stirring speed,specific interfacial area and temperature on the extraction rate in both systems were discussed,suggesting that the extractions were mixed bulk phases-interfacial control process.Supported by the experimental data,the corresponding rate equations for Ce(Ⅳ) extraction system and Ce(Ⅳ)-F^- mixture extraction system were obtained.The experimental results indicated the rate-controlling step.The kinetics model was deduced from the rate-controlling step and consistent with the rate equation. 展开更多
关键词 Ce(Ⅳ)-F--system Bif-ILE kinetics model extraction kinetics constant interfacial area cell with laminar flow
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Automatic Generation of the Planning Tunnel High Speed Craft Hull Form 被引量:4
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作者 Morteza Ghassabzadeh Hassan Ghassemi 《Journal of Marine Science and Application》 2012年第4期453-461,共9页
The creation of geometric model of a ship to determine the characteristics of hydrostatic and hydrodynamic, and also for structural design and equipments arrangement are so important in the ship design process. Planni... The creation of geometric model of a ship to determine the characteristics of hydrostatic and hydrodynamic, and also for structural design and equipments arrangement are so important in the ship design process. Planning tunnel high speed craft is one of the crafts in which, achievement to their top speed is more important. These crafts with the use of tunnel have the aero-hydrodynamics properties to diminish the resistance, good sea-keeping behavior, reduce slamming and avoid porpoising. Because of the existence of the tunnel, the hull form generation of these crafts is more complex and difficult. In this paper, it has attempted to provide a method based on geometry creation guidelines and with an entry of the least control and hull form adjustment parameters, to generate automatically the hull form of plarming tunnel craft. At first, the equations of mathematical model are described and subsequent, three different models generated based on present method are compared and analyzed. Obviously, the generated model has more application in the early stages of design. 展开更多
关键词 planning tunnel craft hull form automatic generation high speed craft
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Simultaneous removal of ethyl acetate, benzene and toluene with gliding arc gas discharge 被引量:1
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作者 Zheng BO Jian-hua YAN +2 位作者 Xiao-dong LI Yong CHI Ke-fa CEN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第5期695-701,共7页
The simultaneous removal of ethyl acetate, benzene and toluene with relatively low or high initial concentration is studied using a laboratory scale gliding arc gas discharge (GA) reactor. Good decomposition efficienc... The simultaneous removal of ethyl acetate, benzene and toluene with relatively low or high initial concentration is studied using a laboratory scale gliding arc gas discharge (GA) reactor. Good decomposition efficiencies are obtained which proves that the GA is effective for the treatment of volatile organic compounds (VOCs) with either low or high concentration. A theoretical decomposition mechanism is proposed based on detection of the species in the plasma region and analysis of the decomposition by-products. This preliminary investigation reveals that the GA has potential to be applied to the treatment of exhaust air during color printing and coating works, by either direct removal or combination with activated carbon adsorption/desorption process. 展开更多
关键词 Plasma Gliding arc gas discharge (GA) Volatile organic compounds (VOCs) Simultaneous removal Printing and coating process
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Effect of Structural Parameters on the Performance of NS High-efficiency Composite TraysⅠ.The Effect of Aperture and Opening Ratio on NS High-efficiency Composite Trays 被引量:2
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作者 Qiao Yingyun Tian Yuanyu +1 位作者 Xu Jingfang Xie Kechang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2009年第3期56-61,共6页
In this paper,the structure and characteristics of the NS high-efficiency composite trays based on the doublelayer aperture jet sieve plate and compositely structured packing were investigated.The effect of aperture a... In this paper,the structure and characteristics of the NS high-efficiency composite trays based on the doublelayer aperture jet sieve plate and compositely structured packing were investigated.The effect of aperture and opening ratio of plate on the fluid dynamics of the NS high-efficiency composite trays,such as the dry tray pressure drop,the wet tray pressure drop,the entrainment,the froth height,the leakage and mass transfer characteristics,were investigated.As a result, the low pressure drop,the high efficiency and the high capacity are the main advantages of the NS high-efficiency composite trays compared to other types of trays.According to this study,small aperture is useful for reducing the pressure drop and entrainment with a high mass transfer efficiency;while large aperture can achieve high capacity and efficiency in a broader operating range at the same pressure drop and entrainment. 展开更多
关键词 NS high-efficiency composite trays APERTURE opening ratio fluid dynamics mass transfer characteristics
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Necessary and Sufficient Conditions for Consensus in Third Order Multi-Agent Systems 被引量:9
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作者 Chi Huang Guisheng Zhai Gesheng Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第6期1044-1053,共10页
We deal with a consensus control problem for a group of third order agents which are networked by digraphs.Assuming that the control input of each agent is constructed based on weighted difference between its states a... We deal with a consensus control problem for a group of third order agents which are networked by digraphs.Assuming that the control input of each agent is constructed based on weighted difference between its states and those of its neighbor agents, we aim to propose an algorithm on computing the weighting coefficients in the control input. The problem is reduced to designing Hurwitz polynomials with real or complex coefficients. We show that by using Hurwitz polynomials with complex coefficients, a necessary and sufficient condition can be obtained for designing the consensus algorithm. Since the condition is both necessary and sufficient, we provide a kind of parametrization for all the weighting coefficients achieving consensus. Moreover, the condition is a natural extension to second order consensus, and is reasonable and practical due to its comparatively decreased computation burden. The result is also extended to the case where communication delay exists in the control input. 展开更多
关键词 Communication delay consensus algorithms graph Laplacians Hurwitz polynomials third order multi-agent systems.
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Resistance and Seakeeping Numerical Performance Analyses of a Semi-Small Waterplane Area Twin Hull at Medium to High Speeds 被引量:1
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作者 Giuliano Vernengo Dario Bruzzone 《Journal of Marine Science and Application》 CSCD 2016年第1期1-7,共7页
The hydrodynamic analysis of a new semi-small waterplane area twin hull (SWATH) suitable for various applications such as small and medium size passenger ferries is presented. This may be an attractive crossover con... The hydrodynamic analysis of a new semi-small waterplane area twin hull (SWATH) suitable for various applications such as small and medium size passenger ferries is presented. This may be an attractive crossover configuration resulting from the merging of two classical shapes: a conventional SWATH and a fast catamaran. The final hull design exhibits a wedge-like waterline shape with the maximum beam at the stem; the hull ends with a very narrow entrance angle, has a prominent bulbous bow typical of SWATH vessels, and features full stern to arrange waterjet propellers. Our analysis aims to perform a preliminary assessment of the hydrodynamic performance of a hull with such a complex shape both in terms of resistance of the hull in calm water and seakeeping capability in regular head waves and compare the performance with that of a conventional SWATH. The analysis is performed using a boundary element method that was preliminarily validated on a conventional SWATH vessel. 展开更多
关键词 small waterplane area twin hull (SWATH) semi-SWATH ship resistance SEAKEEPING response amplitude operators boundary element method rankine source distribution
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Numerical Simulation of a Planing Vessel at High Speed 被引量:15
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作者 Yumin Su Qingtong Chen +1 位作者 Hailong Shen Wei Lu 《Journal of Marine Science and Application》 2012年第2期178-183,共6页
Planing vessels are applied widely in civil and military situations.Due to their high speed,the motion of planning vessels is complex.In order to predict the motion of planning vessels,it is important to analyze the h... Planing vessels are applied widely in civil and military situations.Due to their high speed,the motion of planning vessels is complex.In order to predict the motion of planning vessels,it is important to analyze the hydrodynamic performance of planning vessels at high speeds.The computational fluid dynamic method(CFD) has been proposed to calculate hydrodynamic performance of planning vessels.However,in most traditional CFD approaches,model tests or empirical formulas are needed to obtain the running attitude of the planing vessels before calculation.This paper presents a new CFD method to calculate hydrodynamic forces of planing vessels.The numerical method was based on Reynolds-Averaged Navier-Stokes(RANS) equations.The volume of fluid(VOF) method and the six-degrees-of-freedom equation were applied.An effective process was introduced to solve the numerical divergence problem in numerical simulation.Compared with experimental results,numerical simulation results indicate that both the running attitude and hydrodynamic performance can be predicted well at high speeds. 展开更多
关键词 planing vessel RANS equations running attitude six degrees of freedom equations VOF
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Effectiveness of quality physical education in improving students' manipulative skill competency 被引量:3
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作者 Weiyun Chen Weimo Zhu +2 位作者 Steve Mason Austin Hammond-Bennett Andrew Colombo-Dougovito 《Journal of Sport and Health Science》 SCIE 2016年第2期231-238,共8页
Purpose: This study aimed to examine the extent to which the quality physical education teaching (QPET) practices contributed to improving 4th- and 5th-grade students' manipulative skill competency. Methods: Part... Purpose: This study aimed to examine the extent to which the quality physical education teaching (QPET) practices contributed to improving 4th- and 5th-grade students' manipulative skill competency. Methods: Participants were 9 elementary physical education (PE) teachers and their 4th- and 5th-grade students (n = 2709 3420). The students' skill competency was assessed with 3 manipulative skills using PE metrics assessment rubrics. The PE teachers' levels of QPET were assessed by coding 63 videotaped lessons using the assessing quality teaching rubrics (AQTR), which consisted of 4 essential dimensions including task design, task presentation, class management, and instructional guidance. Codes were confirmed through inter-rater reliability (82.4%, 84.5%, and 94%). Data were analyzed through descriptive statistics, multiple R2 regression models, and independent sample t tests. Results: This study indicated that the 4 essential dimensions of QPET were all significant contributors to students' manipulative skill competency. These predictors were significantly higher for boys than for girls in soccer and striking skills, while they were significantly higher for girls than for boys in throwing skill competency. Of the 4 essential dimensions of QPET, task presentation played the most significant role in contributing to all 3 skill competencies for both boys and girls. Further, students who experienced high QPET were significantly more skillfully competent than those students who did not have this experience. Conclusion: It was concluded that the QPET practices played a significantly critical role in contributing to students' manipulative skill competency. 展开更多
关键词 Assessment of quality teaching Essential dimensions of teaching Manipulative skill competency Skill assessment
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Combustion and energy balance of aluminum holding furnace with bottom porous brick purging system 被引量:3
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作者 ZHANG Jia-qi ZHOU Nai-jun ZHOU Shan-hong 《Journal of Central South University》 SCIE EI CAS 2012年第1期200-205,共6页
For acquiring the details in aluminum holding furnace with bottom porous brick purging system,efforts were performed to try to find out the potential optimal operation schemes.By adopting transient analysis scheme and... For acquiring the details in aluminum holding furnace with bottom porous brick purging system,efforts were performed to try to find out the potential optimal operation schemes.By adopting transient analysis scheme and constant boundary temperature,combustion in the furnace was investigated numerically using computational fluid dynamics(CFD).The predicted gas temperature shows good agreement with the measured results,and the predicted energy distribution of the furnace is consistent with that obtained from energy balance experiment,which confirms the reliability of the numerical solution.The results show that as the fuel-air mixture temperature rises up from 300 K to 500 K,the energy utilization of the furnace could increase from 34.55% to 37.14%.However,as the excess air coefficient increases from 1.0 to 1.4,energy utilization drops from 34.55% to 29.56%.Increasing the combustion temperature is the most effective way to improve the energy efficiency of the furnace.High reactant temperature and medium excess air coefficient are recommended for high operation performance,and keeping the furnace jamb sealed well for avoiding leakage has to be emphasized. 展开更多
关键词 aluminum holding furnace COMBUSTION FLOW numerical study computational fluid dynamics
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Effects of a flexible net barrier on the dynamic behaviours and interception of debris flows in mountainous areas 被引量:4
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作者 HUO Miao ZHOU Jia-wen +1 位作者 YANG Xing-guo ZHOU Hong-wei 《Journal of Mountain Science》 SCIE CSCD 2017年第10期1903-1918,共16页
Flexible net barriers are a new type of effective mitigation measure against debris flows in valleys and can affect the kinematic energy and mass of debris flows. Here, ten flume tests were performed to study the dyna... Flexible net barriers are a new type of effective mitigation measure against debris flows in valleys and can affect the kinematic energy and mass of debris flows. Here, ten flume tests were performed to study the dynamic behaviours of debris flows with differences in volumes, concentrations(solid volume fraction), and travel distances after interception by a uniform flexible net barrier. A high-speed camera was used to monitor the whole test process, and their dynamic behaviours were recorded. A preliminary computational framework on energy conversion is proposed according to the deposition mechanisms and outflow of debris flow under the effects of the flexible net barrier. The experimental results show that the dynamic interaction process between a debris flow and the flexible net barrier can be divided into two stages:(a) the two-phase impact of the leading edge of the debris flow with the net and(b) collision and friction between the body of the debris flow and intercepted debris material. The approach velocity of a debris flow decreases sharply(a maximum of 63%) after the interception by the net barrier, and the mass ratio of the debris material being intercepted and the kinetic energy ratio of the debris material being absorbed by the net barrier are close due to the limited interception efficiency of the flexible net barrier, which is believed to be related to the flexibility. The energy ratio of outflow is relative small despite the large permeability of the flexible net barrier. 展开更多
关键词 Debris flow Flexible net barrier Dynamic behaviours Interception efficiency Kinetic energy absorption High speed photography
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A new approach to quantifying vehicle induced turbulence for complex traffic scenarios 被引量:3
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作者 Yesul Kim Li Huang +1 位作者 Sunling Gong Charles Q.Jia 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第1期71-78,共8页
Traffic-related pollutants adversely affect air quality, especially in regions near major roadways. The vehicleinduced turbulence(VIT) is a significant factor that controls the initial dilution, dispersion, and ultima... Traffic-related pollutants adversely affect air quality, especially in regions near major roadways. The vehicleinduced turbulence(VIT) is a significant factor that controls the initial dilution, dispersion, and ultimately the chemical and physical fate of pollutants by altering the conditions in the microenvironment. This study used a computational fluid dynamics(CFD) software FLUENT to model the vehicle-induced turbulence(VIT) generated on roadways, with a focus on impact of vehicle-vehicle interactions, traffic density and vehicle composition on turbulent kinetic energy(TKE). We show, for the first time, that the overall TKE from multiple vehicles traveling in series can be estimated by superimposing the TKE of each vehicle, without considering the distance between them while the distance is greater than one vehicle length. This finding is particularly significant since it enables a new approach to VIT simulations where the overall TKE is calculated as a function of number of vehicles. We found that the interactions between vehicles traveling next to each other in adjacent lanes are insignificant,regardless the directions of the traffic flow. Consequently, simulations of different traffic scenarios can be substantially simplified by treating two-way traffic as one-way traffic, with less than 5% difference in the overall volume-averaged TKE. We also developed equations that allow the estimation of the overall volume-averaged TKE as a function of the number and the type of vehicles. 展开更多
关键词 Computational fluid dynamics Turbulent kinetic energy Vehicle-induced turbulence Road-induced turbulence Mixed traffic
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Simulation of Hydrodynamic Performance of Drag and Double Reverse Propeller Podded Propulsors 被引量:6
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作者 Chunyu Guo Pengfei Dou +1 位作者 Tao Jing Dagang Zhao 《Journal of Marine Science and Application》 CSCD 2016年第1期16-27,共12页
The unsteady performance of drag and double reverse propeller podded propulsors in open water was numerically simulated using a computational fluid dynamics (CFD) method. A moving mesh method was used to more realis... The unsteady performance of drag and double reverse propeller podded propulsors in open water was numerically simulated using a computational fluid dynamics (CFD) method. A moving mesh method was used to more realistically simulate propulsor working conditions, and the thrust, torque, and lateral force coefficients of both propulsors were compared and analyzed. Forces acting on different parts of the propulsors along with the flow field distribution of steady and unsteady results at different advance coefficients were compared. Moreover, the change of the lateral force and the difference between the abovementioned two methods were mainly analyzed. It was shown that the thrust and torque results of both methods were similar, with the lateral force results having the highest deviation 展开更多
关键词 podded propulsor PROPELLER lateral force computational fluid dynamics (CFD) hydrodynamic performance moving mesh method
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Fundamental movement skills training to promote physical activity in children with and without disability: A pilot study 被引量:1
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作者 Catherine M. Capio Cindy H.R Sit +2 位作者 Kathlynne F. Eguia Bruce Abernethy Richard S.W. Masters 《Journal of Sport and Health Science》 SCIE 2015年第3期235-243,共9页
Background: A positive association between fundamental movement skills (FMS) and physical activity (PA) has been shown in previous research of children with and without disability. This pilot study explored a cau... Background: A positive association between fundamental movement skills (FMS) and physical activity (PA) has been shown in previous research of children with and without disability. This pilot study explored a causal mechanism for such relationship, and hypothesized that when FMS proficiency is improved, enhanced PA uptake will be found in children with and without disability. It was further hypothesized that improving FMS proficiency will have a greater impact on children with disability than those without disability. Methods: Participants include typically developing (TD) children without disability and children with cerebral palsy (CP), who were allocated to FMS training groups (CP-FMS n = 12, TD-FMS n = 13) and control groups (CP-C n = 12, TD-C n = 13). Training groups practiced five FMS (run, jump, kick, throw, catch) in weekly 45-min sessions for 4 weeks. Control groups had their regular physiotherapy (CP) or physical education (TD) sessions. FMS were evaluated using process- and product-oriented measures, and PA was measured using accelerometers, before and after training. Results: It was verified that training groups gained improvements in FMS while control groups did not. No significant changes in weekday PA were found. Increased weekend moderate to vigorous physical activity (MVPA) was found in the CP-FMS group, while decreased weekend sedentary time was found in the CP-FMS and TD-FMS groups. The percentages of participants who exceeded the minimum detectable change (MDC9o) in MVPA and sedentary time were larger in children with CP than in children without disability. Conclusion: The findings suggest that improved FMS proficiency could potentially contribute to heightened PA and decreased sedentary time during weekends for children. Such effect of improved FMS proficiency on PA appears to be greater in those with physical disability than in those without disability. It is recommended that the findings of this pilot study should be further examined in future research. 展开更多
关键词 Cerebral palsy Fundamental movement skills Motor learning Physical activity Sedentary behavior
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On Translator's Subjectivity in the Chinese Version of Pride and Prejudice Translated by Wang Keyi
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作者 张楠 《International English Education Research》 2016年第2期88-90,共3页
As the center and subject of the translation, translator' s subjectivity plays a great role in translation research and more and more attention has been aroused. Since the first version of Pride and Prejudice came in... As the center and subject of the translation, translator' s subjectivity plays a great role in translation research and more and more attention has been aroused. Since the first version of Pride and Prejudice came into being, Chinese translators have begun to show great interest in translating this novel, and there are more than ten translated Chinese versions now. Scholars have conducted a lot of research about this novel and its various translated versions. Among all these Chinese versions, Wang Keyi' s version is relatively earlier and is also the most popular one. Thus, it attracts many readers' eyes and there are increasing comments and studies on this version. There are also studies analyzing or comparing several versions from the perspective of translator' s subjectivity. While, few articles are published to analyze this version from the three elements of translator' s subjectivity: initiatives, passiveness, and purposiveness. They are also three basic features of translator' s subjectivity, in which translator' s subjectivity reflects. It is also the three features that consist of the translator' s subjectivity. Therefore, the comprehensive and intensive research of translator' s subjectivity in the Chinese version of Pride and Prejudice has great realistic meaning and practical values. 展开更多
关键词 the translator' s subjectivity INITIATIVES passiveness purposiveness Pride and Prejudice
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Hydrodynamic Performance of Flapping-foil Propulsion in the Influence of Vortices 被引量:1
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作者 张曦 苏玉民 +1 位作者 杨亮 王兆立 《Journal of Marine Science and Application》 2010年第2期213-219,共7页
Fish are able to make good use of vortices.In a complex flow field,many fish continue to maintain both efficient cruising and maneuverability.Traditional man-made propulsion systems perform poorly in complex flow fiel... Fish are able to make good use of vortices.In a complex flow field,many fish continue to maintain both efficient cruising and maneuverability.Traditional man-made propulsion systems perform poorly in complex flow fields.With fish-like propulsion systems,it is important to pay more attention to complex flow fields.In this paper,the influence of vortices on the hydrodynamic performance of 2-D flapping-foils was investigated.The flapping-foil heaved and pitched under the influence of inflow vortices generated by an oscillating D-section cylinder.A numerical simulation was run based the finite volume method,using the computational fluid dynamics(CFD) software FLUENT with Reynolds-averaged Navier-Stokes(RANS) equations applied.In addition,dynamic mesh technology and post processing systems were also fully used.The calculations showed four modes of interaction.The hydrodynamic performance of flapping-foils was analyzed and the results compared with experimental data.This validated the numerical simulation,confirming that flapping-foils can increase efficiency by absorbing energy from inflow vortices. 展开更多
关键词 flapping-foil VORTEX numerical simulation hydrodynamic performance save energy
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Magneto-hydrodynamic flow of squeezed fluid with binary chemical reaction and activation energy 被引量:2
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作者 S.AHMAD M.FAROOQ +2 位作者 N.A.MIR Aisha ANJUM M.JAVED 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第5期1362-1373,共12页
The present exploration is conducted to describe the motion of viscous fluid embedded in squeezed channel under the applied magnetics effects.The processes of heat and mass transport incorporate the temperature-depend... The present exploration is conducted to describe the motion of viscous fluid embedded in squeezed channel under the applied magnetics effects.The processes of heat and mass transport incorporate the temperature-dependent binary chemical reaction with modified Arrhenius theory of activation energy function which is not yet disclosed for squeezing flow mechanism.The flow,heat and mass regime are exposed to be governed via dimensionless,highly non-linear,ordinary differential equations (ODEs) under no-slip walls boundary conditions.A well-tempered analytical convergent procedure is adopted for the solutions of boundary value problem.A detailed study is accounted through graphs in the form of flow velocity field,temperature and fluid concentration distributions for various emerging parameters of enormous interest.Skin-friction,Nusselt and Sherwood numbers have been acquired and disclosed through plots.The results indicate that fluid temperature follows an increasing trend with dominant dimensionless reaction rate σ and activation energy parameter E.However,an increment in σ and E parameters is found to decline in fluid concentration.The current study arises numerous engineering and industrial processes including polymer industry,compression and injection shaping,lubrication system,formation of paper sheets,thin fiber,molding of plastic sheets.In the area of chemical engineering,geothermal engineering,cooling of nuclear reacting,nuclear or chemical system,bimolecular reactions,biochemical process and electrically conducting polymeric flows can be controlled by utilizing magnetic fields.Motivated by such applications,the proposed study has been developed. 展开更多
关键词 squeezing flow magneto-hydrodynamics (MHD) activation energy binary chemical reaction
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