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WATuning:A Workload-Aware Tuning System with Attention-Based Deep Reinforcement Learning

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Journal of Computer Science & Technology 2021年第4期36卷 741-761页

作者： jia-ke Ge Yan-Feng Chai Yun-Peng Chai key Laboratory of Data Engineering and Knowledge Engineering of Ministry of Education Renmin University of China Beijing 100872China School of Information Renmin University of ChinaBeijing 100872China College of Computer Science and Technology Taiyuan University of Science and TechnologyTaiyuan 030027China

Configuration tuning is essential to optimize the performance of systems(e.g.,databases,key-value stores).High performance usually indicates high throughput and low *** present,most of the tuning tasks of systems are performed artificially(e.g.,by database administrators),but it is hard for them to achieve high performance through tuning in various types of systems and in various *** recent years,there have been some studies on tuning traditional database systems,but all these methods have some *** this article,we put forward a tuning system based on attention-based deep reinforcement learning named WATuning,which can adapt to the changes of workload characteristics and optimize the system performance efficiently and ***,we design the core algorithm named ATT-Tune for WATuning to achieve the tuning task of *** algorithm uses workload characteristics to generate a weight matrix and acts on the internal metrics of systems,and then ATT-Tune uses the internal metrics with weight values assigned to select the appropriate ***,WATuning can generate multiple instance models according to the change of the workload so that it can complete targeted recommendation services for different types of ***,WATuning can also dynamically fine-tune itself according to the constantly changing workload in practical applications so that it can better fit to the actual environment to make *** experimental results show that the throughput and the latency of WATuning are improved by 52.6%and decreased by 31%,respectively,compared with the throughput and the latency of CDBTune which is an existing optimal tuning method.

关键词： attention mechanism auto-tuning system reinforcement learning(RL) workload-aware

A review of single phase adaptive auto-reclosing schemes for EHV transmission lines

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Protection and Control of Modern Power Systems 2019年第1期4卷 217-226页

作者： Waqar Ahmad Khan Tianshu Bi ke jia State key Laboratory for Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing102206People’s Republic of China Faculty of Engineering Lahore Leads UniversityLahorePunjabPakistan

Statistics shows that transients produced by lightning or momentary links with external objects, have produced more than 80% of faults in overhead lines. Reclosing of circuit breaker (CB) after a pre-defined dead time is very common however reclosing onto permanent faults may damage the power system stability and aggravate severe damage to the system. Thus, adaptive single-phase auto-reclosing (ASPAR) based on investigating existing electrical signals has fascinated engineers and researchers. An ASPAR blocks CB reclosing onto permanent faults and allows reclosing permission once secondary arc is quenched. To address the subject, there have been many ASPARs techniques proposed based on the features trapped in a faulty phase. This paper presents a critical survey of adaptive auto-reclosing schemes that have hitherto been applied to EHV transmission lines.

关键词： Adaptive auto-reclosing Protection EHV transmission lines Temporary faults Permanent faults

Tunable Luminescence Properties and Elucidating the Electronic Structures of Single-Phase Spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)Phosphors for Warm-White-Lighting

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Journal of Renewable Materials 2022年第2期10卷 431-451页

作者： Zun Bi ke jia Yunfei Liu Yinong Lyu State key Laboratory of Materials–Orient Chemical Engineering College of Materials Science and EngineeringNanjing Tech UniversityNanjingChina jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM) NanjingChina jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites NanjingChina

A series of uniform single-phase spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors were prepared via a microwave hydrothermal method by using trisodium citrate dehydrate as *** phase structure,morphology and photoluminescence properties were measured by powder X-ray diffraction,scanning electron microscope and fluorescence spectrometer,*** results show that uniform spherical microcrystals with diameters in the range of 2–4μm are *** the phase and morphology of samples are not significantly changed by doping rare earth(RE^(3+))*** the excitation wavelength of 356 and 365 nm,the samples BaWO 4:0.03Dy^(3+),yTm^(3+)can emit cold white *** order to lower the correlated color temperature(CCT)to get a warm white light,the Eu^(3+)ions were doped into BaWO 4:0.03Dy^(3+),0.01Tm^(3+).Especially,under the excitation of 365 nm,BaWO 4:0.03Dy^(3+),0.01Tm^(3+),0.03Eu^(3+)phosphor shew a bright warm white light with color coordi-nate of(0.4013,0.3629)and CCT of 3288 ***,in the BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors,the energy transfer mechanism among Dy^(3+),Tm^(3+)and Eu^(3+)ions have been discussed and the change of electron structures have been calculated by first-principles *** results shew that the uniform single-phase spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors could be favorable candidates in warm white LEDs.

关键词： Barium tungstate microwave hydrothermal method spherical warm white lighting electron structures

A voltage resonance-based single-ended online fault location algorithm for DC distribution networks

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Science China(Technological Sciences) 2016年第5期59卷 721-729页

作者： jia ke LI Meng BI Tian Shu YANG Qi Xun State key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University

A novel single-ended online fault location algorithm is investigated for DC distribution networks. The proposed algorithm calculates the fault distance based on the characteristics of the voltage resonance. The Prony's method is introduced to extract the characteristics. A novel method is proposed to solve the pseudo dual-root problem in the calculation process. The multiple data windows are adopted to enhance the robustness of the proposed algorithm. An index is proposed to evaluate the accuracy and validity of the results derived from the various data windows. The performances of the proposed algorithm in different fault scenarios were evaluated using the PSCAD/EMTDC simulations. The results show that the algorithm can locate the faults with transient resistance using the 1.6 ms data of the DC-side voltage after a fault inception and offers a good precision.

关键词： protection fault location DC distribution VSC voltage resonance Prony's method

A potential application in quantum networks-Deterministic quantum operation sharing schemes with Bell states

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Science China(Physics,Mechanics & Astronomy) 2016年第6期59卷 41-48页

作者： ke jia Zhang Long Zhang Ting Ting Song Ying Hui Yang School of Mathematical Science Hei Long Jiang University State key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Department of Computer Science College of Information Science and Technology Jinan University

In this paper, we propose certain different design ideas on a novel topic in quantum cryptography — quantum operation sharing(QOS). Following these unique ideas, three QOS schemes, the "HIEC"(The scheme whose messages are hidden in the entanglement correlation), "HIAO"(The scheme whose messages are hidden with the assistant operations) and "HIMB"(The scheme whose messages are hidden in the selected measurement basis), have been presented to share the single-qubit operations determinately on target states in a remote node. These schemes only require Bell states as quantum resources. Therefore, they can be directly applied in quantum networks, since Bell states are considered the basic quantum channels in quantum networks. Furthermore, after analyse on the security and resource consumptions, the task of QOS can be achieved securely and effectively in these schemes.

关键词： quantum operation sharing quantum secret sharing quantum secure direct communication quantum networks

Synthesis and Characterization of PEG-scuteilarin Conjugates,a Potential PEG Ester Prodrug for the Oral Delivery of Scutellarin

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Chinese Chemical Letters 2006年第1期17卷 85-88页

作者： Qing Song ZHOU Xue Hua jiaNG jia Rui YU ke jia LI West China School of Pharmacy Sichuan University Chengdu 610041

Highly water soluble esters of scutellarin with variable molecular weight polyethylene glycol （PEG） were prepared via PEGylation. The physicochemical properties and the stabilities under different conditions were investigated. By PEG modification, the greatly increased water solubility and desirable partition coefficient of scuteUarin were obtained, and the results showed that these conjugates were potential prodrugs for the oral delivery of scuteUarin.

关键词： Scutellarin PEGylation prodrug physicochcmical properties stability.

Fitting function representation for strain fields and its application to the optimizing process

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International Journal of Minerals,Metallurgy and Materials 2014年第6期21卷 556-562页

作者： Kun Chen ke-jia Liu Li-qun Wei Yi-tao Yang School of Materials Science and Engineering Shanghai Institute of Technology School of Materials Science and Engineering Shanghai University

A fitted function method to describe the strain fields during forging was discussed to optimize the homogeneous distribution of strain in the axial forging zones during successive stretching. The results are verified by experiment and numerical simulation, and the devia-tions between experiment and simulation are less than 24%. Therefore, the fitted function method can be applied to optimize the stretching process for large forgings. The optimal value of feed determined by the analytic method ensures that the degree of inhomogeneity in strain in the axial ingot zone is less than 6%. This work provides a mathematic model to optimize technological parameters in stretch forging of large ingots.

关键词： forging strain fitting fimcfion representation optimization

Regulating Empathy: Exploring the Process through Agents and Strategies

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International Journal of Mental Health Promotion 2023年第12期25卷 1265-1285页

作者： ke jia Xiuli Liu School of Psychology Northeast Normal UniversityChangchun130024China

Empathy is a complex emotional phenomenon that plays a crucial role in promoting cooperation and social cohesion within human ***,there is ongoing debate regarding the mechanisms that underlie the generation of *** the importance of biological emotional resonance in empathy is widely recognized,the inﬂuence of cognitive regulation on empathetic responses cannot be *** article seeks to review the agents and strategies involved in regulating empathy to construct a dynamic model depicting the *** model highlights that the impact of speciﬁc goals on empathy regulation is not deﬁnitive;rather,it depends on an individual’s interpretation and pursuit of goals,which can either enhance or hinder *** effectively regulate empathy,individuals employ various emotion regulation strategies,the effectiveness and frequency of which can vary depending on individual and contextual *** context provides a speciﬁc pathway for understanding the generation of *** research should be conducted to systematically investigate the regulatory mechanisms of empathy by integrating contextual factors and individual ***,it is incredibly important to enhance the impact of empathy on social interactions by utilizing its ability to be controlled for intervention and prediction purposes.

关键词： Empathy regulation goal assessment motivation

Review on Renewable Energy Source Fault Characteristics Analysis

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 963-972页

作者： Tianshu Bi Bin Yang ke jia Liming Zheng Qian Liu Qixun Yang School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206China

The increase of renewable energy sources(RESs),especially wind power and photovoltaic,is bringing different fault features to the power system compared with the traditional syn-chronous generator,resulting in the urgent need for precise fault *** to the sequentially activated fault features,the short circuit characteristics of RES can be divided into three fault *** the staged framework of fault duration,the published research is reviewed to provide a systematic analysis of RES fault ***'s concluded that the hardware parameter determines the sub-transient fault features of RES,whereas RES control begins to dominate during the following transient ***,the neglection of voltage transition and unavailable RES output phase shall impede the application of the analytical conclusions in protection *** solve the existing problems,interaction among RES and networks must be figured ***,the fault calculation of the integral RES-grid system is offered as the research prospect.

关键词： Fault characteristics analysis fault stages renewable energy sources