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Regulation effect of the grille spacing of a funnel-type grating water–sediment separation structure on the debris flow performance
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作者 LI Shuai GU Tianfeng +2 位作者 WANG Jiading WANG Fei LI Pu 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2283-2304,共22页
The size of pores or the grille spacing of water–sediment separation structures directly affects their regulation effect on the debris flow performance.A suitable pore size or grille spacing can effectively improve t... The size of pores or the grille spacing of water–sediment separation structures directly affects their regulation effect on the debris flow performance.A suitable pore size or grille spacing can effectively improve the water–sediment separation ability of the structure.The new funnel-type grating water–sediment separation structure(FGWSS)combines vertical and horizontal structures and provides a satisfactory water–sediment separation effect.However,the regulation effect of the grille spacing of the structure on the debris flow performance has not been studied.The regulation effect of the structure grille spacing on the debris flow performance is studied through a flume test,and the optimal structure grille spacing is obtained.An empirical equation of the relationship between the relative grille spacing of the structure and the sediment separation rate is established.Finally,the influence of the water–sediment separation structure on the regulation effect of debris flows is examined from two aspects:external factors(properties of debris flows)and internal factors(structural factors).The experimental results show that the gradation characteristics of solid particles in debris flows constitute a key factor affecting the regulation effect of the structure on the debris flow performance.The optimum grille spacing of the FGWSS matches the particle size corresponding to the material distribution curves d85~d90 of the debris flow.The total separation rate of debris flow particles is related to the grille spacing of the structure and the content of coarse and fine particles in the debris flow. 展开更多
关键词 Debris flow Water–sediment separation structure Grille spacing performance regulation effect
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ROS2 Real-time Performance Optimization and Evaluation
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作者 Yanlei Ye Zhenguo Nie +3 位作者 Xinjun Liu Fugui Xie Zihao Li Peng Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第6期36-50,共15页
Real-time interaction with uncertain and dynamic environments is essential for robotic systems to achieve functions such as visual perception,force interaction,spatial obstacle avoidance,and motion planning.To ensure ... Real-time interaction with uncertain and dynamic environments is essential for robotic systems to achieve functions such as visual perception,force interaction,spatial obstacle avoidance,and motion planning.To ensure the reliability and determinism of system execution,a flexible real-time control system architecture and interaction algorithm are required.The ROS framework was designed to improve the reusability of robotic software development by providing a distributed structure,hardware abstraction,message-passing mechanism,and application prototypes.Rich ecosystems for robotic development have been built around ROS1 and ROS2 architectures based on the Linux system.However,because of the fairness scheduling principle of the default Linux system design and the complexity of the kernel,the system does not have real-time computing.To achieve a balance between real-time and non-real-time computing,this paper uses the transmission mechanism of ROS2,combines it with the scheduling mechanism of the Linux operating system,and uses Preempt_RT to enhance the real-time computing of ROS1 and ROS2.The real-time performance evaluation of ROS1 and ROS2 is conducted from multiple perspectives,including throughput,transmission mode,QoS service quality,frequency,number of subscription nodes and EtherCAT master.This paper makes two significant contributions:firstly,it employs Preempt_RT to optimize the native ROS2 system,effectively enhancing the real-time performance of native ROS2 message transmission;secondly,it conducts a comprehensive evaluation of the real-time performance of both native and optimized ROS2 systems.This comparison elucidates the benefits of the optimized ROS2 architecture regarding real-time performance,with results vividly demonstrated through illustrative figures. 展开更多
关键词 ROS real-time system optimization Preempt_RT real-time performance evaluation of ROS2
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Dimensionality regulation in tin halide perovskite solar cells: Toward high performance and stability
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作者 Huanhuan Yao Shurong Wang +2 位作者 Zhiwen Jin Liming Ding Feng Hao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期144-156,I0005,共14页
Tin halide perovskites(THPs)have received extensive attention due to their low toxicity and excellent optoelectronic properties,and are considered to be the most promising alternatives to develop efficient lead-free p... Tin halide perovskites(THPs)have received extensive attention due to their low toxicity and excellent optoelectronic properties,and are considered to be the most promising alternatives to develop efficient lead-free perovskite solar cells.However,due to the unique and inherent characteristics of Sn^(2+)being easily oxidized to Sn^(4+)and fast crystallization,tin perovskite solar cells(TPSCs)show relatively poor performance and stability,compared to the lead counterparts.Recently,the introduction of bulky organic spacers into three-dimensional(3D)THPs for dimensional regulation can not only prevent the intrusion of water and oxygen,but also inhibit the self-doping effect and ion migration.In this review,we will detail how dimensional regulation enables TPSCs with high performance and superior stability.First,we summarize the intrinsic properties of THPs and analyze the root causes of their poor performance and instability.Next,we discuss the specific structure and types of the dimensional regulation strategy.Then,the mechanism of dimensional regulation is discussed in detail,mainly from inhibiting the Sn^(2+)oxidation,optimizing crystallization,passivating defects,and improving energy level alignment.Finally,future challenges and prospects for dimensional regulation are elaborated to help researchers develop more efficient and stable TPSCs. 展开更多
关键词 Organic spacers Dimensional regulation Long-term stability performance Photovoltaics
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Robust output regulation problem with prescribed performance for nonlinear strict feedback systems
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作者 ZHU Haichao LAN Weiyao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第4期1033-1041,共9页
This paper investigates the problem of robust output regulation control with prospected transient property for strict feedback systems.By employing the internal model principle,the robust output regulation problem wit... This paper investigates the problem of robust output regulation control with prospected transient property for strict feedback systems.By employing the internal model principle,the robust output regulation problem with a prospected property can be transformed to a robust stabilization problem with a new output constraint.Then,by constructing the speed function and adopting barrier Lyapunov function technique,the dynamic feedback controller can be designed not only to drive error output of the closed-loop system entering into a prescribed performance bound within a given finite time,but also to achieve that the error output converges to zero asymptotically.The effectiveness of the results is illustrated by a simulation example. 展开更多
关键词 robust output regulation nonlinear system prescribed performance bound speed function finite time
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Cyber Resilience through Real-Time Threat Analysis in Information Security
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作者 Aparna Gadhi Ragha Madhavi Gondu +1 位作者 Hitendra Chaudhary Olatunde Abiona 《International Journal of Communications, Network and System Sciences》 2024年第4期51-67,共17页
This paper examines how cybersecurity is developing and how it relates to more conventional information security. Although information security and cyber security are sometimes used synonymously, this study contends t... This paper examines how cybersecurity is developing and how it relates to more conventional information security. Although information security and cyber security are sometimes used synonymously, this study contends that they are not the same. The concept of cyber security is explored, which goes beyond protecting information resources to include a wider variety of assets, including people [1]. Protecting information assets is the main goal of traditional information security, with consideration to the human element and how people fit into the security process. On the other hand, cyber security adds a new level of complexity, as people might unintentionally contribute to or become targets of cyberattacks. This aspect presents moral questions since it is becoming more widely accepted that society has a duty to protect weaker members of society, including children [1]. The study emphasizes how important cyber security is on a larger scale, with many countries creating plans and laws to counteract cyberattacks. Nevertheless, a lot of these sources frequently neglect to define the differences or the relationship between information security and cyber security [1]. The paper focus on differentiating between cybersecurity and information security on a larger scale. The study also highlights other areas of cybersecurity which includes defending people, social norms, and vital infrastructure from threats that arise from online in addition to information and technology protection. It contends that ethical issues and the human factor are becoming more and more important in protecting assets in the digital age, and that cyber security is a paradigm shift in this regard [1]. 展开更多
关键词 Cybersecurity Information Security Network Security Cyber Resilience real-time Threat Analysis Cyber Threats Cyberattacks Threat Intelligence Machine Learning Artificial Intelligence Threat Detection Threat Mitigation Risk Assessment Vulnerability Management Incident Response Security Orchestration Automation Threat Landscape Cyber-Physical Systems Critical Infrastructure Data Protection Privacy Compliance regulations Policy Ethics CYBERCRIME Threat Actors Threat Modeling Security Architecture
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A Comparison Between Northern Blotting and Quantitative Real-Time PCR as a Means of Detecting the Nutritional Regulation of Genes Expressed in Roots of Arabidopsis thaliana 被引量:4
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作者 GAN Yin-bo ZHOU Zhong-jing +2 位作者 AN Li-jun BAO Sheng-jie Brian G Forde 《Agricultural Sciences in China》 CAS CSCD 2011年第3期335-342,共8页
Quantitative real-time PCR (qRT-PCR) has become a routine and robust technique for measuring the expression of genes of interest, validating microarray experiments and monitoring biomarkers. However, concerns have b... Quantitative real-time PCR (qRT-PCR) has become a routine and robust technique for measuring the expression of genes of interest, validating microarray experiments and monitoring biomarkers. However, concerns have been raised over the accuracy of qRT-PCR in China as well as in the rest of the world. We have previously used qRT-PCR to study the response of ANR1 and other root-expressed MADS-box genes to fluctuations in the supply of nitrate, phosphate and sulphate under hydroponic growth conditions. In this study, we have used both Northern blotting and qRT-PCR analyses to confirm the nutritional regulation of MADS-box genes in Arabidopsis thaliana and test whether both technologies produce the same results. The information obtained indicated that the qRT-PCR results are consistent with those obtained by Northern blotting hybridization for all the tested root-expressed MADS-box genes, in response to different nitrate, phosphate and sulphate growth conditions. Furthermore, our novel results showed that the expressions of AGL12, AGL18, and AGL19 were all down regulated in response to S and P re-supply in both qRT-PCR and Northern blotting analyses. 展开更多
关键词 Arabidopsis thaliana MADS-BOX nutrient regulation Northern blotting quantitative real-time PCR
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Performance analysis model for real-time Ethernet-based computer numerical control system 被引量:2
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作者 万加富 李迪 +1 位作者 涂钰青 张春华 《Journal of Central South University》 SCIE EI CAS 2011年第5期1545-1553,共9页
In order to optimize the embedded system implementation for Ethernet-based computer numerical control (CNC) system, it is very necessary to establish the performance analysis model and further adopt the codesign met... In order to optimize the embedded system implementation for Ethernet-based computer numerical control (CNC) system, it is very necessary to establish the performance analysis model and further adopt the codesign method from the control, communication and computing perspectives. On the basis of analyzing real-time Ethemet, system architecture, time characteristic parameters of control-loop ere, a performance analysis model for real-time Ethemet-based CNC system was proposed, which is able to include the timing effects caused by the implementation platform in the simulation. The key for establishing the model is accomplished by designing the error analysis module and the controller nodes. Under the restraint of CPU resource and communication bandwidth, the experiment with a case study was conducted, and the results show that if the deadline miss ratio of data packets is 0.2%, then the percentage error is 1.105%. The proposed model can be used at several stages of CNC system development. 展开更多
关键词 computer numerical control (CNC) system real-time Ethemet time characteristic parameters performance analysis model manufacturing accuracy
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Performance evaluation of near real-time condition monitoring in haul trucks 被引量:1
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作者 Hemanth Reddy Alla Robert Hall Derek B.Apel 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2020年第6期909-915,共7页
Strategic maintenance plays a key role in ensuring high availability and utilization of the haul trucks,and as equipment began to grow more complex towards the end of the 20th century,there was a need for a proactive ... Strategic maintenance plays a key role in ensuring high availability and utilization of the haul trucks,and as equipment began to grow more complex towards the end of the 20th century,there was a need for a proactive maintenance strategy,which led to the development of condition-based maintenance.Realtime condition monitoring(RTCM)is the ability to perform condition monitoring in real-time and has the ability to alert maintenance and operations of abnormal conditions.These alarms can be used as an indication leading to a problem,and if a suitable corrective action is initiated in time,it could result in significant savings of equipment downtime and repair costs.This study aims to compare some maintenance performance indicators prior to and after implementation of RTCM strategy at a mine site using some tests of statistical significance.The study also indicated the presence of seasonality in the data,and thus the data was deseasonalized and detrended prior to being subjected to the statistical tests.Finally,the results indicated that RTCM strategy has proven to be successful in improving the availability for some of the failure categories chosen in this study. 展开更多
关键词 Haul trucks real-time condition monitoring performance indicators
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Seismic performance evaluation of VCFPB isolated storage tank using real-time hybrid simulation 被引量:1
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作者 Hong Yue Tang Zhenyun +1 位作者 Li Zhenbao Du Xiuli 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2022年第2期501-515,共15页
Variable curvature friction pendulum bearings(VCFPB)effectively reduce the dynamic response of storage tanks induced by earthquakes.Shaking table testing is used to assess the seismic performance of VCFPB isolated sto... Variable curvature friction pendulum bearings(VCFPB)effectively reduce the dynamic response of storage tanks induced by earthquakes.Shaking table testing is used to assess the seismic performance of VCFPB isolated storage tanks.However,the vertical pressure and friction coefficient of the scaled VCFPB in the shaking table tests cannot match the equivalent values of these parameters in the prototype.To avoid this drawback,a real-time hybrid simulation(RTHS)test was developed.Using RTHS testing,a 1/8 scaled tank isolated by VCFPB was tested.The experimental results showed that the displacement dynamic magnification factor of VCFPB,peak reduction factors of the acceleration,shear force,and overturning moment at bottom of the tank,were negative exponential functions of the ratio of peak ground acceleration(PGA)and friction coefficient.The peak reduction factors of displacement,acceleration,force and overturning moment,which were obtained from the experimental results,are compared with those calculated by the Housner model.It can be concluded that the Housner model is applicable in estimation of the acceleration,shear force,and overturning moment of liquid storage tank,but not for the sliding displacement of VCFPBs. 展开更多
关键词 liquid storage tank base isolation variable curvature friction pendulum bearing seismic performance real-time hybrid simulation test
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Optimizing Real-Time Performance of 3D Virtual Mining Environment with MultiGen Creator 被引量:12
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作者 WANGWei-chen JIANGXiao-hong +1 位作者 HANKe-qi HANWen-ji 《Computer Aided Drafting,Design and Manufacturing》 2004年第1期61-69,共9页
System optimization plays a crucial role in developing VR system after 3D modeling, affecting the system's Immersion and Interaction performance enormously. In this article, several key techniques of optimizing a ... System optimization plays a crucial role in developing VR system after 3D modeling, affecting the system's Immersion and Interaction performance enormously. In this article, several key techniques of optimizing a virtual mining system were discussed: optimizing 3D models to keep the polygon number in VR system within target hardware's processing ability; optimizing texture database to save texture memory with perfect visual effect; optimizing database hierarchy structure to accelerate model retrieval; and optimizing LOD hierarchy structure to speed up rendering. 展开更多
关键词 virtual mining system real-time performance OPTIMIZATION MultiGen creator
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Real-time performance of periodic data transmission in EPA industrial Ethernet 被引量:2
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作者 刘宁 仲崇权 莫亚林 《Journal of Beijing Institute of Technology》 EI CAS 2012年第3期336-342,共7页
To evaluate and improve the real-time performance of Ethernet for plant automation(EPA) industrial Ethernet,the real-time performance of EPA periodic data transmission was theoretically and experimentally studied.By... To evaluate and improve the real-time performance of Ethernet for plant automation(EPA) industrial Ethernet,the real-time performance of EPA periodic data transmission was theoretically and experimentally studied.By analyzing information transmission regularity and EPA deterministic scheduling mechanism,periodic messages were categorized as different modes according to their entering-queue time.The scheduling characteristics and delivery time of each mode and their interacting relations were studied,during which the models of real-time performance of periodic information transmission in EPA system were established.On this basis,an experimental platform is developed to test the delivery time of periodic messages transmission in EPA system.According to the analysis and the experiment,the main factors that limit the real-time performance of EPA periodic data transmission and the improvement methods were proposed. 展开更多
关键词 Ethernet for plant automation(EPA) industrial Ethernet periodic data transmission real-time performance delivery time
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Performance Evaluation of Land Use Regulation
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作者 Wang Yumeng Wu Juan +1 位作者 Fang Lingli Zhang Anlu 《Chinese Journal of Population,Resources and Environment》 2010年第1期28-31,共4页
This article makes a quantitative study on economic performance of arable land protection and land use regulation with dummy variable model.It is shown that land use regulation is favorable for economic growth and pro... This article makes a quantitative study on economic performance of arable land protection and land use regulation with dummy variable model.It is shown that land use regulation is favorable for economic growth and protection of arable land and that there are still some problems in the implementation of land use regulation.Thus,it puts forward corresponding suggestion. 展开更多
关键词 regulation of land use performance evaluation SUGGESTION
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Environmental regulation and firms'performance:a quasi-natural experiment from China
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作者 Juan Li Min Zhao Yien Yang 《Chinese Journal of Population,Resources and Environment》 2019年第3期278-294,共17页
This paper investigates whether environmental regulation affects firm's performance including productivity,wage and employment using firm-level data in 1996-2007.The identification uses Two Control Zones(TCZ)polic... This paper investigates whether environmental regulation affects firm's performance including productivity,wage and employment using firm-level data in 1996-2007.The identification uses Two Control Zones(TCZ)policy implemented by the Chinese government in 1998,in which tougher environmental regulations were imposed in TCZ cities but not others.By difference-indifferences estimation,we find that tougher environmental regulation leads to larger increase on both total factor productivity and wage,and firms tend to employ fewer workers under pressure of environmental protection.Heterogeneous tests show that the impacts are better for nonpollution intensive firms,non-exporters and SOEs.Finally,we find that R&D input and exiting firms among industry are the driving forces for enhancing TFP and increasing wage and unemployment. 展开更多
关键词 Environmental regulation firm’s performance Two Control Zones(TCZ) quasi-natural experiment Chinese firm-level data
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The Impacts of Building Regulations on the Thermal Performance and Energy Consumption of Residential Buildings in Riyadh City-Saudi Arabia
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作者 Saleh Baharetha Elsayed Amer Mohammad Kotbi 《Open Journal of Energy Efficiency》 2021年第1期1-21,共21页
Riyadh city is the fastest growing city in Saudi Arabia. The rapid urban growth that happened recently in Riyadh was not based on the traditional urban planning principles, which have been established and applied for ... Riyadh city is the fastest growing city in Saudi Arabia. The rapid urban growth that happened recently in Riyadh was not based on the traditional urban planning principles, which have been established and applied for the city development process. The imported building regulations have created a new urban structures and street patterns. The contemporary urban form in Riyadh city is based mainly on traffic and economic consideration with the neglect of environmental dimensions. This research aims to examine the impacts of building regulations on the thermal performance of residential buildings in Riyadh city, with the ultimate goal of establishing planning guidelines that consider the environmental conditions of the city. The methodology adopted for achieving the aim of this study consists of two phases. First, the literature related to building regulations development in Riyadh, as of 2018, was reviewed. Second, buildings energy simulation was conducted to examine the thermal performance of the typical current status of residential building blocks in Riyadh city, and then several changes to building regulations were made to investigate their impacts on the thermal performance of buildings. The results showed that the impacts of Riyadh building regulations on the thermal performance of residential buildings differ across the evaluated cases. The ratio of building height to street width, urban block street orientation, and building orientation are the main factors affecting thermal performance of buildings within urban block. The study also concludes that adjusting the ratio of building height to the distance between buildings could have a significant impact in reducing cooling loads. This study will help policy makers, planners and designers to investigate the shortcoming in the current building regulations. 展开更多
关键词 Building regulations Energy Consumption Thermal performance Residential Buildings
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Relationship between R&D investment and business performance from the perspective of environmental regulation: Takeing the heavy-polluting industries from 2011 to 2016 as an example
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作者 ZHAO Yu YUE Hong HUANG Ya-jing 《Ecological Economy》 2017年第3期213-226,共14页
In recent years, China has promulgated many laws and regulations of environmental protection, gradually forming an environmental regulation system, and most enterprises are under the dual pressure of environmental pro... In recent years, China has promulgated many laws and regulations of environmental protection, gradually forming an environmental regulation system, and most enterprises are under the dual pressure of environmental protection and business performance. It would be a significant way that enterprises undertake R&D activities for a change. This paper is based on the Shanghai and Shenzhen A-share listed heavy pollution enterprises in 2011-2016, which is based on the review and summary of research results of former researchers, combining with current environmental regulation situation of our country, raising the relevant hypothesis between environmental regulations, R&D investment and business performance against heavy pollution industry. Adopting the method of empirical research, it also built the linear regression model which employs the relevant financial data of heavy-polluting enterprises in China as the statistical research sample. The relationship for heavy-polluting enterprises affected by environmental regulations between environmental protection R&D investment and enterprise business performance was tested. The results show that there is a positive influence on the environmental R&D investment and business performance, and a lag effect upon the R&D investment of enterprises to business performance. Finally, the research results were used to evaluates problems existing in the R&D investment on pollution industry in China as well as business performance and we put forward some suggestions on improving environmental regulation standards and technology innovation consciousness as well as optimizing the structure of R&D investment. 展开更多
关键词 environmental regulation R&D investment business performance empirical research
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Empirical Examination of the Effects of Competition and Regulation on Public Universities and Colleges' Performance in China
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作者 XUE Yao-xuan ZHU Yun-jie +1 位作者 SUN Lin-yan Richard Mweene 《Chinese Business Review》 2007年第2期1-19,共19页
Competition and regulation are indispensable entities for a university's improved performance. Using university rating as an index to performance, empirical analyses with the data from 145 public universities and col... Competition and regulation are indispensable entities for a university's improved performance. Using university rating as an index to performance, empirical analyses with the data from 145 public universities and colleges in China show that increased competition in the education service market is associated with higher university's (college's) performance. And increased competition in R&D may make a quadratic effect on university's (college's) performance. University's performance improves when a university is directed as a branch of the central government because they enjoy some degree of management flexibility more than the local government controlled ones. A major implication of the study is the need to reform competition and regulation for improving universities and colleges' operating performance in China. 展开更多
关键词 COMPETITION regulation universities and colleges' performance in China
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Design strategy and comprehensive performance assessment towards Zn anode for alkaline rechargeable batteries
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作者 Di Yang Jinsheng Li +2 位作者 Changpeng Liu Wei Xing Jianbing Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期122-138,I0004,共18页
Alkaline Zn-based primary batteries have been commercialized in the past decades.However,their success has not been extended to secondary batteries due to the poor cycle reversibility of Zn anodes.Although some resear... Alkaline Zn-based primary batteries have been commercialized in the past decades.However,their success has not been extended to secondary batteries due to the poor cycle reversibility of Zn anodes.Although some research has been conducted on alkaline Zn anodes,their performance is still far from commercial requirements.A variety of degradation mechanisms,including passivation,dendrites,morphological changes,and hydrogen precipitation,are claimed responsible for the failure of alkaline Zn metal anodes.What’s worse,these constraints always interact with each other,which leads to a single strategy being unable to suppress all the issues.Therefore,a comprehensive evaluation of the positive and negative effects of various strategies on performance is important to promote the commercialization of alkaline Zn batteries.Herein,the recent progress and performance of improvement strategies for Zn anode in alkaline conditions are reviewed systematically.First,the principles and challenges of alkaline Zn anodes are briefly analyzed.Then,various design strategies for alkaline Zn anodes from the perspectives of ion and electron regulation are highlighted.Last,through a comprehensive summary of various performance parameters,the advantages and disadvantages of different strategies are compared and evaluated.On the basis of this assessment,we aim to provide more insights into the anode design of high-performance alkaline rechargeable Zn batteries. 展开更多
关键词 Alkaline aqueous batteries Zinc anode regulation strategies performance assessment
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A real-time performance improvement method for composite time scale
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作者 Fangmin Wang Wenlin Li +4 位作者 Hongfei Dai Chunyi Li Jianhua Zhou Shenhui Xue Bo Wang 《Chinese Physics B》 SCIE EI CAS 2024年第9期350-357,共8页
The composite time scale(CTS)provides a stable,accurate,and reliable time scale for modern society.The improvement of CTS’s real-time performance will improve its stability,which strengths related applications’perfo... The composite time scale(CTS)provides a stable,accurate,and reliable time scale for modern society.The improvement of CTS’s real-time performance will improve its stability,which strengths related applications’performance.Aiming at this goal,a method achieved by determining the optimal calculation interval and accelerating adjustment stage is proposed in this paper.The determinants of the CTS’s calculation interval(characteristics of the clock ensemble,the measurement noise,the time and frequency synchronization system’s noise and the auxiliary output generator noise floor)are studied and the optimal calculation interval is obtained.We also investigate the effect of ensemble algorithm’s initial parameters on the CTS’s adjustment stage.A strategy to get the reasonable initial parameters of ensemble algorithm is designed.The results show that the adjustment stage can be finished rapidly or even can be shorten to zero with reasonable initial parameters.On this basis,we experimentally generate a distributed CTS with a calculation interval of 500 s and its stability outperforms those of the member clocks when the averaging time is longer than1700 s.The experimental result proves that the CTS’s real-time performance is significantly improved. 展开更多
关键词 composite time scale real-time performance calculation interval adjustment stage
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Regulating the crystal phase of bismuth-based semiconductors for promoted photocatalytic performance
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作者 Zhaohui Wu Mei-Chi Chong +2 位作者 Shiying Zhang Junshan Li Yongfa Zhu 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第6期1839-1864,共26页
Numerous bismuth-based semiconductors(BBSs)with sophisticated and desirable structures used as photocatalysts for efficient photocatalytic degradation of water organic contaminants have attracted considerable attentio... Numerous bismuth-based semiconductors(BBSs)with sophisticated and desirable structures used as photocatalysts for efficient photocatalytic degradation of water organic contaminants have attracted considerable attention.However,regulating the crystal phases and phase transition of BBSs for promoted photocatalytic performance is ignored.Herein,the unique crystal structure and band structure features of each typical BBSs,and the vital roles on phase controlling of each phase were systematically presented based on the classification of BBSs.Notably,the critical factors for the phase transition of BBSs and intrinsic driving forces endowed by phases of BBSs for enhanced photocatalytic performance of organic contaminants removal were also elucidated.This review will provide systematical guidelines and horizons for regulating the crystal phase and phase transition of BBSs,promoting photocatalytic degradation and mineralization of organic contaminants. 展开更多
关键词 bismuth-based semiconductors phase regulation photocatalytic performances organic contaminants
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Breath-based meditation: A mechanism to restore the physiological and cognitive reserves for optimal human performance 被引量:5
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作者 Kirtigandha Salwe Carter Robert Carter III 《World Journal of Clinical Cases》 SCIE 2016年第4期99-102,共4页
Stress can be associated with many physiologicalchanges resulting in significant decrements in human performance.Due to growing interests in alternative and complementary medicine by Westerners,many of the traditions ... Stress can be associated with many physiologicalchanges resulting in significant decrements in human performance.Due to growing interests in alternative and complementary medicine by Westerners,many of the traditions and holistic yogic breathing practices today are being utilized as a measure for healthier lifestyles.These state-of-the-art practices can have a significant impact on common mental health conditions such as depression and generalized anxiety disorder.However,the potential of yogic breathing on optimizing human performance and overall well-being is not well known.Breathing techniques such as alternate nostril,Sudarshan Kriya and bhastrika utilizes rhythmic breathing to guide practitioners into a deep meditative state of relaxation and promote self-awareness.Furthermore,yogic breathing is physiologically stimulating and can be described as a natural"technological"solution to optimize human performance which can be categorized into:(1)cognitive function(i.e.,mind,vigilance);and(2)physical performance(i.e.,cardiorespiratory,metabolism,exercise,whole body).Based on previous studies,we postulate that daily practice of breathing meditation techniques play a significant role in preserving the compensatory mechanisms available to sustain physiological function.This preservation of physiological function may help to offset the time associated with reaching a threshold for clinical expression of chronic state(i.e.,hypertension,depression,dementia)or acute state(i.e.,massive hemorrhage,panic attic)of medical conditions.However,additional rigorous biomedical research is needed to evaluate the physiological mechanisms of various forms of meditation(i.e.,breath-based,mantra,mindfulness)on human performance.These efforts will help to define how compensatory reserve mechanisms of cardiovascular and immune systems are modulated by breath-based meditation.While it has been suggested that breath-based meditation is easier for beginning practitioners when compared to other forms of meditation more research is needed to elucidate these observations.A breath-based meditation sequence suchas Sudarshan Kriya has the potential to help develop an individual’s self-awareness and support better integration of the brain(i.e.,mind)with other organ systems(i.e.,body)for enhanced human performance. 展开更多
关键词 MEDITATION BREATHING technique Cognitive reserve NEUROPHYSIOLOGY Stress Human performance EMOTIONAL regulation
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