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CAD/CAE OF THE WORKING CHARACTERISTICS OF A NEW TYPE OF FLUID COUPLING SHOCK ABSORBER 被引量:4
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作者 Yang Ping Zhong Yifang Zhou JiSchool of Mechanical Science and Engineering, Huazhong University of Science and Technology,Wuhan 430074, ChinaLiu Yong Guilin Institute of Electronic Technology 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第3期222-227,共6页
For purpose of simulation of the working characteristics of a new type offluid coupling shock absorber for vibration protection of sensitive equipment, a physical model ispresented by analyzing the internal fluid dyna... For purpose of simulation of the working characteristics of a new type offluid coupling shock absorber for vibration protection of sensitive equipment, a physical model ispresented by analyzing the internal fluid dynamic phenomenon with respect to the coupling shockabsorber and implemented in MATLAB software package. Using the model it is possible to evaluate theimportance of different factors for design of the shock absorber. In the meantime, the key-modelmachine is designed for coupling dynamic test. Comparisons with experimental results confirm thevalidity of the model. So the CAD/CAE software has been developed in MATLAB for design andexperimental test of the new coupling shock absorber. 展开更多
关键词 Fluid coupling shock absorber working characteristics MODEL SIMULATION
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Report on the Work of NPC Standing Committee 2016(Extract)
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作者 张德江 《The Journal of Human Rights》 2016年第2期154-169,共16页
Major Initiatives of 2015A.We made new strides in key areas of legislation The law is of great value in the governance of a country,and good laws are a prerequisite for good governance.Focusing on the key task of rais... Major Initiatives of 2015A.We made new strides in key areas of legislation The law is of great value in the governance of a country,and good laws are a prerequisite for good governance.Focusing on the key task of raising the quality of legislation,we channeled great effort into advancing legislation in key areas.Large in number, 展开更多
关键词 EXTRACT Report on the Work of npc Standing Committee 2016 npc
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Effect of Working Temperature on the Resistance Characteristic of a Pleated Stainless Steel Woven Filter
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作者 李娟 石玉美 汪荣顺 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第6期949-954,共6页
包括渗透系数和 pleated 不锈钢的压力落下进化的抵抗特征上的工作温度的效果有 0.5 &#x3bc 的一种名字的毛孔尺寸的编织过滤器; m 被学习了。渗透系数基于压力落下数据和 Darcy 的法律被获得。在三个过滤实验,在 283 K,在 85 K... 包括渗透系数和 pleated 不锈钢的压力落下进化的抵抗特征上的工作温度的效果有 0.5 &#x3bc 的一种名字的毛孔尺寸的编织过滤器; m 被学习了。渗透系数基于压力落下数据和 Darcy 的法律被获得。在三个过滤实验,在 283 K,在 85 K 的氮和在 18 K 的液体氦的纯二氧化碳分别地被采用。渗透系数在低温实验法的温度由于过滤器元素的冷精神病医生在工作温度减少,这被发现。然后,二种 feed 泥浆,液体氮的混合和在 85 K 的固体的二氧化碳,和在 18 K 的液体氦和稳固的氮的混合,流进过滤器房间。稳固的粒子在过滤器表面上被扔通过过滤器形成一个过滤器蛋糕和净化的液体流动。压力落下进化在这二温度上显示出一样的趋势,这被发现,它能与高过滤效率被划分成三个阶段,显示为低温实验法的申请的过滤器的可行性。然而,变体蛋糕电阻被获得,它在更低的工作温度在 feed 泥浆从在稳固的粒子之间的不同相互作用被结果。 展开更多
关键词 不锈钢过滤器 工作温度 阻力特性 固态二氧化碳 渗透系数 固体微粒 液体流动 温度变化
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Carcass and Meat Characteristics of Hararghe Highland Bull after Draught Work Service
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作者 Yohannes Urgesa Ye’i Yesihak Yusuf Mummed +2 位作者 Mohammed Yusuf Kurtu Mengistu Urge Leta Travis Gene O’Quinn 《Open Journal of Animal Sciences》 2023年第4期458-477,共20页
The objectives of the study were to examine the effects of draught work on carcass characteristics, meat yield potential, and distribution along primal cuts in Hararghe highland bulls fed on net energy requirement bas... The objectives of the study were to examine the effects of draught work on carcass characteristics, meat yield potential, and distribution along primal cuts in Hararghe highland bulls fed on net energy requirement basis. Twelve bulls were sorted into three groups of four animals each and assigned to three treatment hours: control (0), 4, or 6, using a complete randomized design (CRD). The results of the study show that there are no significant differences (p > 0.05) in slaughter weight, hot carcass weight (HCW), chilling loss, total edible and non-edible offal, fat thickness (FT), deboned meat yield (kg), meat to bone ratio, muscle distribution, and proportion of kidney, pelvic, and heart fat (KPH%) among the treatment groups. However, the hot carcass-based dressing percentage was significantly lowered (p < 0.05) in bulls that work 4 or 6 hours a day. Meat yield was strongly correlated with HCW (r = 0.74) and FT (r = 0.73). Therefore, the number of hours the bull spent on draught work did not negatively impact meat yield or quality. Consequently, the research suggests that utilizing Hararghe highland bulls for draught service, four or six hours a day is viable for dual advantages: crop cultivation and marketable carcass. 展开更多
关键词 BULLS Draught Work Carcass characteristics MEAT Muscle Distribution
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A new diagnostic method for identifying working conditions of submersible reciprocating pumping systems 被引量:3
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作者 Yu Deliang Zhang Yongming +2 位作者 Bian Hongmei Wang Xinmin Qi Weigui 《Petroleum Science》 SCIE CAS CSCD 2013年第1期81-90,共10页
The submersible pumping unit is a new type of pumping system for lifting formation fluids from onshore oil wells, and the identification of its working condition has an important influence on oil production. In this p... The submersible pumping unit is a new type of pumping system for lifting formation fluids from onshore oil wells, and the identification of its working condition has an important influence on oil production. In this paper we proposed a diagnostic method for identifying the working condition of the submersible pumping system. Based on analyzing the working principle of the pumping unit and the pump structure, different characteristics in loading and unloading processes of the submersible linear motor were obtained at different working conditions. The characteristic quantities were extracted from operation data of the submersible linear motor. A diagnostic model based on the support vector machine (SVM) method was proposed for identifying the working condition of the submersible pumping unit, where the inputs of the SVM classifier were the characteristic quantities. The performance and the misjudgment rate of this method were analyzed and validated by the data acquired from an experimental simulation platform. The model proposed had an excellent performance in failure diagnosis of the submersible pumping system. The SVM classifier had higher diagnostic accuracy than the learning vector quantization (LVQ) classifier. 展开更多
关键词 Submersible reciprocating pump working condition failure diagnosis linear motor characteristic quantity support vector machine misjudgment rate
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Complementary parametric probit regression and nonparametric classi?cation tree modeling approaches to analyze factors affecting severity of work zone weather-related crashes 被引量:1
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作者 Ali Ghasemzadeh Mohamed M.Ahmed 《Journal of Modern Transportation》 2019年第2期129-140,共12页
Identifying risk factors for road traffic injuries can be considered one of the main priorities of transportation agencies. More than 12,000 fatal work zone crashes were reported between 2000 and 2013. Despite recent ... Identifying risk factors for road traffic injuries can be considered one of the main priorities of transportation agencies. More than 12,000 fatal work zone crashes were reported between 2000 and 2013. Despite recent efforts to improve work zone safety, the frequency and severity of work zone crashes are still a big concern for transportation agencies. Although many studies have been conducted on different work zone safety-related issues, there is a lack of studies that investigate the effect of adverse weather conditions on work zone crash severity. This paper utilizes probit–classification tree, a relatively recent and promising combination of machine learning technique and conventional parametric model, to identify factors affecting work zone crash severity in adverse weather conditions using 8 years of work zone weatherrelated crashes (2006–2013) in Washington State. The key strength of this technique lies in its capability to alleviate the shortcomings of both parametric and nonparametric models. The results showed that both presence of traffic control device and lighting conditions are significant interacting variables in the developed complementary crash severity model for work zone weather-related crashes. Therefore, transportation agencies and contractors need to invest more in lighting equipment and better traffic control strategies at work zones, specifically during adverse weather conditions. 展开更多
关键词 ADVERSE WEAtheR Work zone Safety CRASH characteristics PROBIT model Decision tree
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Dynamic characteristics of a working platform supported by an AMG
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作者 张钢 《High Technology Letters》 EI CAS 2008年第2期193-198,共6页
A coupled electromechanical dynamic model for a working platform supported by an active magneticguide(AMG)is set up according to the special stiffness and damping theory of maglev system and theunique vibration of the... A coupled electromechanical dynamic model for a working platform supported by an active magneticguide(AMG)is set up according to the special stiffness and damping theory of maglev system and theunique vibration of the working platform for a machine tool.The dynamic characteristics of a workingplatform supported by an AMG are studied using different groups of control parameters.Results show thatthe dynamic characteristics of the platform system,such as critical vibration frequency,vibration modeand so on,can be improved by adjusting the control parameters.This research offers theoretical supportfor ultra-high-speed and ultra-precise machine working platform designs,including the structure of plat-forms,the design of electromagnets,and the establishment of the control parameters. 展开更多
关键词 加工平台 磁导性 动力性能 通信技术
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Job characteristics and staying engaged in work of nurses: Empirical evidence from Malaysia 被引量:1
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作者 Noraini Othman Aizzat Mohd Nasurdin 《International Journal of Nursing Sciences》 CSCD 2019年第4期432-438,共7页
Objective: The purpose of this study is to examine the relationship between job characteristics (job autonomy,job feedback,skill variety,task identity,task significance) and work engagement of nurses in Malaysia.Metho... Objective: The purpose of this study is to examine the relationship between job characteristics (job autonomy,job feedback,skill variety,task identity,task significance) and work engagement of nurses in Malaysia.Methods: A survey using self-administered questionnaires was used to collect data from a sample of 856 staff nurses working in eight public hospitals in Malaysia.A shortened nine-item version of the Utrecht Work Engagement Scale(UWES-9) was used to measure work engagement.The UWES-9 comprises three dimensions,which was measured with three items each: vigor,dedication,and absorption.Job characteristics (job autonomy,job feedback,skill variety,task identity,task significance) were measured with the corresponding subscales of the Job Diagnostic Survey.Each subscale consisted of three items.Hypotheses were tested using hierarchical regression analysis.Results: Findings indicated that all the five demographic variables (age,marital status,education,organizational tenure,job tenure) were unrelated to work engagement.The results further revealed that job autonomy (β=0.19,P < 0.01),job feedback (β=0.10,P < 0.01),task identity (β=0.13,P < 0.01),and task significance (β=0.08,P< 0.05) were positively related to work engagement.Skill variety (β=0.03,P> 0.05),however,did not affect work engagement.Conclusion: Job autonomy,job feedback,task identity,and task significance are important factors in predicting work engagement.The findings of this study highlighted the need to incorporate these core dimensions in nursing management to foster work engagement. 展开更多
关键词 Hospitals Job characteristics MALAYSIA Nursing staff Work engagement
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Characteristics and Construction Technology Analysis of Static Pressure Prestressed Pipe Piles in Construction Engineering 被引量:1
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作者 Wu Cuipeng 《Journal of Architectural Research and Development》 2018年第3期55-58,共4页
The development of urbanization has led to an increase in the number and scale of construction projects and the types of building construction engineering are getting advance and diverse due to the rapid development o... The development of urbanization has led to an increase in the number and scale of construction projects and the types of building construction engineering are getting advance and diverse due to the rapid development of technology.One of them is the static pressure prestressed pipe pile which is the most commonly used technology in modern building construction work.It is mainly used for pile foundation in construction work,and it has the advantages in less pollution,low noise,and high efficiency compared to the traditional pile foundation.Study on the characteristics of static pressure prestressed pipe pile must be carried out and strengthened the research to increase the effectiveness and quality of static pressure prestressed pipe pile on construction works.This paper is mainly to analyzed the characteristic and construction technology of static pressure prestressed pipe piles on building construction work. 展开更多
关键词 building CONSTRUCTION WORK STATIC pressure PRESTRESSED PIPE PILE characteristic CONSTRUCTION WORK technology
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Novel method for operating characteristics test of a hydraulic pump
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作者 王向周 陆叶 郑戍华 《Journal of Beijing Institute of Technology》 EI CAS 2015年第1期74-82,共9页
The traditional testing method of a hydraulic pump requires a large amount of test data from a variety of pump working conditions. The test is usually time-consuming and energy-consu- ming. And the accurate characteri... The traditional testing method of a hydraulic pump requires a large amount of test data from a variety of pump working conditions. The test is usually time-consuming and energy-consu- ming. And the accurate characteristic curves of the pump were hardly obtained due to a limited a- mount and discreteness of the test data. In order to simplify the test procedure and improve the test accuracy, a novel method for measuring hydraulic pump operating characteristic based on multi-ele- ment nonlinear regression (NLMR) modeling is proposed in this paper. The main idea of this model- ing method is establishing a mathematical model to predict the performance parameters of the hy- draulic pump, only a small amount of test data is needed. Consequently, the pump operating charac- teristics in any working conditions are obtained. And the test results of the pump are easily charac- terized in the graphs, charts, tables and so on. The evaluations of the model are carried out and dis- cussed in this paper. The result shows that the test error of the novel method can be controlled to be about 0. 1%. Compared with the traditional test method, the proposed method reduces greatly the test time and the random error of the test data, and improves the efficiency and accuracy of the pump test. 展开更多
关键词 hydraulic pump TEST MODEL work characteristics
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Comparative experimental study of machining characteristics of air-mixed EDM and conventional EDM 被引量:2
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作者 李立青 郭永丰 +1 位作者 白基成 郭艳玲 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第2期170-173,共4页
A new method of electrical discharge machining (EDM) in air-mixed medium—air-mixed EDM was presented, and comparative experiments were carried out to compare the machining characteristics of air-mixed EDM with conven... A new method of electrical discharge machining (EDM) in air-mixed medium—air-mixed EDM was presented, and comparative experiments were carried out to compare the machining characteristics of air-mixed EDM with conventional EDM. The experimental results showed that better machining performances were obtained with tool electrode as the cathode and workpiece as the anode. It was found that the material removal rate (MRR) was higher, the tool electrode relative wear ratio (TWR) was lower and the surface roughness (SR) quality was better in the case of air-mixed EDM than that of conventional EDM, and the reasons bringing out the results were analyzed. 展开更多
关键词 混气电火花加工 常规电火花加工 机加工性能 比较实验研究
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Mediating effect of work engagement between job characteristics and nursing performance among general hospital nurses
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作者 Eun-Kyung Lee Sun-Hee Kim Jin-Hwa Park 《Frontiers of Nursing》 2021年第3期241-248,共8页
Objective:This study aimed to determine the effects of job characteristics and work engagement on the nursing performance of nurses working in general hospitals.Methods:Data were collected from 169 nurses who are work... Objective:This study aimed to determine the effects of job characteristics and work engagement on the nursing performance of nurses working in general hospitals.Methods:Data were collected from 169 nurses who are working in a general hospital in South Korea by using a cross-sectional descriptive survey design.Results:Nurses’job characteristics and work engagement showed positive effects on nursing performance.This effect was magnified when work engagement was used as a mediating variable.Conclusions:The findings elucidate the factors influencing job performance and provide managers with important information for developing programs to improve the job skills and work engagement of nurses. 展开更多
关键词 general hospitals job characteristics NURSE work engagement work performance
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The Fatherhood Premium: Mirage or Reality? How Do Occupational Characteristics Matter 被引量:1
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作者 Ruoqing Rachelle Wang-Cendejas Ling Bai 《Journal of Sociology Study》 2018年第4期157-170,共14页
关键词 职业特征 物质 工作结构 生产率 社会经济 人口统计 信息网络 模型估计
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A New Kind of Pilot Controlled Proportional Direction Valve with Internal Flow Feedback 被引量:24
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作者 QUAN Long XU Xiaoqing YAN Zheng ZHANG Xiaojun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第1期60-65,共6页
Proportional direction valve is one of the most fundamental elements in electronic-hydraulic control technique. Its function is to control the operating speed, direction, position, and strength of output force of the ... Proportional direction valve is one of the most fundamental elements in electronic-hydraulic control technique. Its function is to control the operating speed, direction, position, and strength of output force of the hydraulic actuator continuously. Considering the different application and the cost, the existing technique mainly includes the internal feedback valve used in open loop system, and the electronic closed loop controlled valve used in closed loop system. Because of their different mechanical structure and the gre at different in performance, it brings inconvenience for customer to select, also inconvenience for enterprise to produce. Aiming at this problem, the idea of combining the above two kinds of valves into one body is proposed first, and then the new valve's structure to realize this target is designed. The idea intends to apply the displacement pilot flow feedback control principle in present 2-position 2-way valve system to the proportional direction valve of 3-position 4-way system. Newly designed feed forward controller can decouple the interference between the internal feedback and the electronic closed loop. Redundant conversion is designed to electronic switch mode. Experiment on dynamic and static characteristic of new proportional direction valve in internal feedback control mode and electronic closed loop control mode is discussed to prove the new theory is correct. Although the new valve is of excellent dynamic response characteristic, its steady control characteristic in open loop control mode needs to be improved further. The research results prepare one new fundamental element for electronic-hydraulic control technology. 展开更多
关键词 pilot flow feedback proportional direction valve working principle characteristic research
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HYDRAULIC CHARACTERISTICS OF PARTIAL OPENING OF THE WORKING GATE FOR A DISCHARGE TUNNEL 被引量:5
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作者 WU Jian-hua FENG Shu-rong +1 位作者 WU Wei-wei RUAN Shi-ping 《Journal of Hydrodynamics》 SCIE EI CSCD 2007年第4期488-493,共6页
The partial opening of the working gate for a discharge tunnel is used more and more widely in the various conditions, such as releasing discharge to meet the needs of the various stages under construction, or of the ... The partial opening of the working gate for a discharge tunnel is used more and more widely in the various conditions, such as releasing discharge to meet the needs of the various stages under construction, or of the operations at low reservoir levels. In this article the hydraulic characteristics were investigated of the partial opening of the working gate based on the physical model experiments of the discharge tunnel for the Longtan Hydropower Project, including the discharge coefficient, the surface profile of the free flow section, the bottom pressure distribution of the tunnel with an aerator, the cavity length just from the ramp, and the wall pressure of the curve section of the outlet. Some new issues were discussed and the properties were presented of the partial opening of the gate. 展开更多
关键词 partial opening hydraulic characteristics working gate discharge tunnel
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Numerical simulation on magnetic confinement characteristics of internal vortex electrostatic cyclone precipitator under different working voltages 被引量:1
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作者 Jianping Zhang Jiaqi Wang +3 位作者 Peng Che Youqi Wang Zhiyao Lu Zibing Qu 《Particuology》 SCIE EI CAS CSCD 2023年第3期156-163,共8页
Aiming at improving the capture performance of internal vortex electrostatic cyclone precipitator(ECP),a theoretical model with mechanics-electric-magnetic coupling was established,the collection efficiency of magneti... Aiming at improving the capture performance of internal vortex electrostatic cyclone precipitator(ECP),a theoretical model with mechanics-electric-magnetic coupling was established,the collection efficiency of magnetic confinement ECP under different working voltages was simulated,and the influence of magnetic flux intensity on the removal performance of submicron particles was explored.Results show that the number of particles escaped from the cyclone is greatly reduced after the introduction of magnetic field and electric field,indicating that charging effect and magnetic confinement are more conductive to trap submicron particles in the internal vortex ECP.The lower the working voltage is,the worse the charging lifting effect is,but the stronger the magnetic confinement characteristics are.Furthermore,the contributions of charging effect to collection efficiency and magnetic confinement characteristics are more obvious at a weaker magnetic flux density.The research results can provide a practical new idea for the innovative design of ECP. 展开更多
关键词 Magnetic confinement characteristics working voltage Internal vortex ECP Submicron particles Capture performance
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Determination of work-hardening exponent for sheet metal using three-point method 被引量:1
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作者 康达昌 田浩彬 刘现平 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第3期275-277,共3页
Three characteristic points in the deformation history of a fractured tensile specimen are selected tocalculate two values of n( n1 and n2 ) to represent the hardening ability of material during the homogeneous plas-t... Three characteristic points in the deformation history of a fractured tensile specimen are selected tocalculate two values of n( n1 and n2 ) to represent the hardening ability of material during the homogeneous plas-tic deformation and the following large plastic deformation. Experimental results obtained with mild streel andred copper show that n determined using the three-point method proposed is better to describe the hardening a-bility of material. It is therefore concluded that three-point method can be used to describe the hardening prop-erty of material during both homogeneous deformation and large plastic deformation. 展开更多
关键词 金属板 加工硬化指数 三点法 塑性变形 拉伸试验
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A Review of English Test for International Communication(ETIC)——Based on an Example of Written Communication Task from ETIC "Intermediate"
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作者 王莎 《海外英语》 2020年第2期128-130,共3页
The research examines a new accreditation test system of English Test for International Communication(ETIC)launched in 2016 and developed by China Language Assessment(a professional testing service established by Beij... The research examines a new accreditation test system of English Test for International Communication(ETIC)launched in 2016 and developed by China Language Assessment(a professional testing service established by Beijing Foreign Studies Uni⁃versity).The analysis and discussion is conducted through an example procedure of such assessment performance on ETIC.The rel⁃evant review aims to sort out the theoretical framework and main characteristic of the system,address the consequence and decision elicited from the assessment,and conclude the contribution of ETIC as a task-ability assessment to the use of language.It shows the interpretation of ETIC is generalizable and relevant to make the decision for test users.Such test system of ETIC is accountable to the stakeholders for the intended use.The research also puts forward the direction of the language assessment in China. 展开更多
关键词 ETIC AUA frame work Task characteristics Task-ability assessment Language ability
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Moderating Effect of Job Type on Job Characteristic Worker Outcome Relationships
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作者 Justina M. Oliveira Charles Scherbaum 《Psychology Research》 2017年第3期164-185,共22页
关键词 调节作用 类型 特性 特征模型 工作满意度 测试工作 JCM 设计
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习近平文化思想:新时代党领导文化建设的科学理论指南与根本行动遵循 被引量:8
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作者 黄蓉生 耿靖 《西南大学学报(社会科学版)》 北大核心 2024年第1期1-13,共13页
习近平文化思想是新时代中国共产党领导文化建设实践的理论升华,构成了习近平新时代中国特色社会主义思想的文化篇。学习贯彻习近平文化思想,需要坚持理论与实践相结合、历史与现实相统一的原则,梳理百余年来中国共产党领导文化建设的脉... 习近平文化思想是新时代中国共产党领导文化建设实践的理论升华,构成了习近平新时代中国特色社会主义思想的文化篇。学习贯彻习近平文化思想,需要坚持理论与实践相结合、历史与现实相统一的原则,梳理百余年来中国共产党领导文化建设的脉络,回顾党的十八大以来历次宣传思想工作会议及其理论成果,揭示习近平文化思想正式提出的划时代意义。习近平文化思想涵括了文化的地位作用、前进方向、建设目标、实践路径、发展动力等丰富内涵;彰显了明体达用、体用贯通,与时俱进、开放包容,人民至上、胸怀天下等理论品格;体现了坚定文化自信和文化主体性的极端重要性、“两个结合”的方法准则、新的文化使命等原创性贡献。新时代党领导文化建设在加强党对宣传思想文化工作的领导、培育和践行社会主义核心价值观等方面取得了历史性成就。切实担负起新的文化使命,务必以习近平文化思想为指导,明确新的文化使命的本质要义和精神底蕴,强化理论武装、坚持自信自强、推动文化建设高质量发展,在继续推动文化繁荣、建设文化强国、建设中华民族现代文明的奋斗实践中展现新作为。 展开更多
关键词 习近平文化思想 中国共产党 宣传思想文化工作 新的文化使命 中国特色社会主义文化
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