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Probing the structure of multi-center molecules with odd–even high harmonics 被引量:3
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作者 苏宁 于术娟 +2 位作者 李卫艳 杨世平 陈彦军 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期274-280,共7页
We study high-order harmonic generation(HHG) from multi-center asymmetric linear molecules numerically and analytically. Our simulations show that odd and even HHG spectra of the asymmetric multi-center system respo... We study high-order harmonic generation(HHG) from multi-center asymmetric linear molecules numerically and analytically. Our simulations show that odd and even HHG spectra of the asymmetric multi-center system respond differently to the change of the molecular structure. Specifically, when the internuclear distances between these nuclei of the molecule have a small change, the odd spectra usually do not change basically, but the even spectra differ remarkably. Based on this phenomenon, a simple procedure is proposed to probe the positions of these nuclei with odd–even HHG. Our results shed light on attosecond probing of the structure of multi-center molecules using HHG. 展开更多
关键词 odd-even harmonics multi-center asymmetric molecules molecular structure
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SDN Orchestration for Dynamic End-to-End Control of Data Center Multi-Domain Optical Networking 被引量:3
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作者 LIU Lei 《China Communications》 SCIE CSCD 2015年第8期10-21,共12页
New and emerging use cases, such as the interconnection of geographically distributed data centers(DCs), are drawing attention to the requirement for dynamic end-to-end service provisioning, spanning multiple and hete... New and emerging use cases, such as the interconnection of geographically distributed data centers(DCs), are drawing attention to the requirement for dynamic end-to-end service provisioning, spanning multiple and heterogeneous optical network domains. This heterogeneity is, not only due to the diverse data transmission and switching technologies, but also due to the different options of control plane techniques. In light of this, the problem of heterogeneous control plane interworking needs to be solved, and in particular, the solution must address the specific issues of multi-domain networks, such as limited domain topology visibility, given the scalability and confidentiality constraints. In this article, some of the recent activities regarding the Software-Defined Networking(SDN) orchestration are reviewed to address such a multi-domain control plane interworking problem. Specifically, three different models, including the single SDN controller model, multiple SDN controllers in mesh, and multiple SDN controllers in a hierarchical setting, are presented for the DC interconnection network with multiple SDN/Open Flow domains or multiple Open Flow/Generalized Multi-Protocol Label Switching( GMPLS) heterogeneous domains. I n addition, two concrete implementations of the orchestration architectures are detailed, showing the overall feasibility and procedures of SDN orchestration for the end-to-endservice provisioning in multi-domain data center optical networks. 展开更多
关键词 数据中心 网络控制 业务流程 SDN 端到端 控制平面技术 通用多协议标签交换 控制器模型
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Cost-Aware Multi-Domain Virtual Data Center Embedding 被引量:1
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作者 Xiao Ma Zhongbao Zhang Sen Su 《China Communications》 SCIE CSCD 2018年第12期190-207,共18页
Virtual data center is a new form of cloud computing concept applied to data center. As one of the most important challenges, virtual data center embedding problem has attracted much attention from researchers. In dat... Virtual data center is a new form of cloud computing concept applied to data center. As one of the most important challenges, virtual data center embedding problem has attracted much attention from researchers. In data centers, energy issue is very important for the reality that data center energy consumption has increased by dozens of times in the last decade. In this paper, we are concerned about the cost-aware multi-domain virtual data center embedding problem. In order to solve this problem, this paper first addresses the energy consumption model. The model includes the energy consumption model of the virtual machine node and the virtual switch node, to quantify the energy consumption in the virtual data center embedding process. Based on the energy consumption model above, this paper presents a heuristic algorithm for cost-aware multi-domain virtual data center embedding. The algorithm consists of two steps: inter-domain embedding and intra-domain embedding. Inter-domain virtual data center embedding refers to dividing virtual data center requests into several slices to select the appropriate single data center. Intra-domain virtual data center refers to embedding virtual data center requests in each data center. We first propose an inter-domain virtual data center embedding algorithm based on label propagation to select the appropriate single data center. We then propose a cost-aware virtual data center embedding algorithm to perform the intra-domain data center embedding. Extensive simulation results show that our proposed algorithm in this paper can effectively reduce the energy consumption while ensuring the success ratio of embedding. 展开更多
关键词 VIRTUAL data center EMBEDDING multi-DOMAIN cost-aware LABEL PROPAGATION
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Minimum MSE Weights of Adjusted Summary Estimator of Risk Difference in Multi-Center Studies 被引量:1
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作者 Chukiat Viwatwongkasem Jirawan Jitthavech +1 位作者 Dankmar Bohning Vichit Lorchirachoonkul 《Open Journal of Statistics》 2012年第1期48-59,共12页
The simple adjusted estimator of risk difference in each center is easy constructed by adding a value c on the number of successes and on the number of failures in each arm of the proportion estimator. Assessing a tre... The simple adjusted estimator of risk difference in each center is easy constructed by adding a value c on the number of successes and on the number of failures in each arm of the proportion estimator. Assessing a treatment effect in multi-center studies, we propose minimum MSE (mean square error) weights of an adjusted summary estimate of risk difference under the assumption of a constant of common risk difference over all centers. To evaluate the performance of the proposed weights, we compare not only in terms of estimation based on bias, variance, and MSE with two other conventional weights, such as the Cochran-Mantel-Haenszel weights and the inverse variance (weighted least square) weights, but also we compare the potential tests based on the type I error probability and the power of test in a variety of situations. The results illustrate that the proposed weights in terms of point estimation and hypothesis testing perform well and should be recommended to use as an alternative choice. Finally, two applications are illustrated for the practical use. 展开更多
关键词 Minimum MSE WEIGHTS Optimal WEIGHTS Cochran-Mantel-Haenszel WEIGHTS Inverse Variance WEIGHTS multi-center STUDIES Risk Difference
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Multi-Order and Multi-Center Metallogenic Zoning of Yinshan Cu-Au Polymetallic Ore Deposit,Jiangxi Province,China
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作者 Mo Cehui Liu Danying Feng Zhiwen Xia WeflwaChina University of Geosciences , Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1993年第1期70-73,共4页
Yinshan anticline is the product of tectono-dynamic deformation - metamorphism .Along the axis of the anticline exists a brittle-ductile shearing zone which obviously controls the ore-formation . Mineralization occurs... Yinshan anticline is the product of tectono-dynamic deformation - metamorphism .Along the axis of the anticline exists a brittle-ductile shearing zone which obviously controls the ore-formation . Mineralization occurs along the axis of the anticline in a width of about 1000m .In the mining area .volcano- subvolcanic rocks of Early Yanshan period are divided into three cycles :Ⅰ intermediate acidic dacite lava and dacite porphyry ;Ⅱ acidic amphibole liparite and quartz porphyry;Ⅲ intermediate andesite porphyrite . Among them activities of ⅠandⅡ cycles are more intensive and are intimately related to the mineralization . Yinshan ore deposit is the result of combinative processes of tectono -dynamic and volcano -magmatic hydrothermal fluids, so that mere are two centers of metallogenic zoning, one being the axial strain zone of Yinshan anticline which is the center of first order, and the other being porphyry stock , 2nd order. 展开更多
关键词 Yinshan polymetallic deposit multi-order and multi-center metallogenic zoning brittle-ductile shearing zone porphyry stock .
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METHOD OF CENTERS ALGORITHM FORMULTI-OBJECTIVE PROGRAMMING PROBLEMS
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作者 Tarek Emam 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1128-1142,共15页
In this paper, we consider a method of centers for solving multi-objective programming problems, where the objective functions involved are concave functions and the set of feasible points is convex. The algorithm is ... In this paper, we consider a method of centers for solving multi-objective programming problems, where the objective functions involved are concave functions and the set of feasible points is convex. The algorithm is defined so that the sub-problems that must be solved during its execution may be solved by finite-step procedures. Conditions are given under which the algorithm generates sequences of feasible points and constraint multiplier vectors that have accumulation points satisfying the KKT conditions. Finally, we establish convergence of the proposed method of centers algorithm for solving multiobjective programming problems. 展开更多
关键词 method of centers multi-OBJECTIVE CONVERGENCE approximated efficient solution
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Multi-Hazard Evaluation Using Cluster Analysis—For Designated Evacuation Centers of Yokohama
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作者 Tsutomu Ochiai Takahisa Enomoto 《Journal of Geographic Information System》 2021年第2期243-259,共17页
Hazard maps are usually prepared for each disaster, including seismic hazard maps, flood hazard maps, and landslide hazard maps. However, when the general public attempts to check their own disaster risk, most are lik... Hazard maps are usually prepared for each disaster, including seismic hazard maps, flood hazard maps, and landslide hazard maps. However, when the general public attempts to check their own disaster risk, most are likely not aware of the specific types of disaster. So, first of all, we need to know what kind<span style="font-family:;" "="">s</span><span style="font-family:;" "=""> of hazards are important. However, the information that integrates multiple hazards is not well maintained, and there are few such studies. On the other hand, in Japan, a lot of hazard information is being released on the Internet. So, we summarized and assessed hazard data that can be accessed online regarding shelters (where evacuees live during disasters) and their catchments (areas assigned to each shelter) in Yokohama City, Kanagawa Prefecture. Based on the results, we investigated whether a grouping by cluster analysis would allow for multi-hazard assessment. We used four natural disasters (seismic, flood, tsunami, sediment disaster) and six parameters of other population and senior population. However, since the characteristics of the population and the senior population were almost the same, only population data was used in the final examination. From the cluster analysis, it was found that it is appropriate to group the designated evacuation centers in Yokohama City into six groups. In addition, each of the six groups was found <span>to have explainable characteristics, confirming the effectiveness of multi-hazard</span> creation using cluster analysis. For example, we divided, all hazards are low, both flood and Seismic hazards are high, sediment hazards are high, etc. In many Japanese cities, disaster prevention measures have been constructed in consideration of ground hazards, mainly for earthquake disasters. In this paper, we confirmed the consistency between the evaluation results of the multi-hazard evaluated here and the existing ground hazard map and examined the usefulness of the designated evacuation center. Finally, the validity was confirmed by comparing this result with the ground hazard based on the actual measurement by the past research. In places where the seismic hazard is large, the two are consistent with the fact that the easiness of shaking by actual measurement is also large.</span> 展开更多
关键词 multi Hazard Cluster Analysis Open Data Designated Evacuation center GIS
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The Volume Effect and Safety of 6% Hydroxyethyl Starch 130/0.4 in Patients Undergoing Major Elective Surgery: An Uncontrolled, Open-Labeled, Multi-Center Study
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作者 Nobutada Morioka Makoto Ozaki +6 位作者 Michiaki Yamakage Hiroshi Morimatsu Yasuyuki Suzuki Frank Bepperling Hideki Miyao Akiyoshi Namiki Kiyoshi Morita 《Open Journal of Anesthesiology》 2013年第7期326-337,共12页
Purpose: The primary aim of this study was to investigate volume effect and safety of up to 50 mL/kg BW 6% hydroxyethyl starch (HES) 130/0.4 in adult and pediatric patients undergoing major elective surgery. The need ... Purpose: The primary aim of this study was to investigate volume effect and safety of up to 50 mL/kg BW 6% hydroxyethyl starch (HES) 130/0.4 in adult and pediatric patients undergoing major elective surgery. The need to infuse human albumin may be reduced or avoided in Japan if these large doses 6% HES 130/0.4 can be infused. Methods: The study was an uncontrolled, open-labeled, multi-center trial. Fifteen adult and 5 pediatric patients undergoing major elective surgery received 6% HES 130/0.4 (Voluven&#174) with a maximum dose of 50 mL/kg from the start of surgery until 2 hours after the end of surgery according to a treatment algorithm. The primary efficacy endpoint was the volume effect of 6% HES 130/0.4 determined by the volume of saved albumin during the investigational period and the time course of hemodynamic stability in adult and pediatric patients. Safety parameters were fluid balance, hemodynamic and laboratory parameters ECG, local and systemic tolerance and adverse events. Results: Adult patients received a mean of 32.0 mL/kg of 6% HES 130/0.4. For 12 out of 15 adult patients an average amount of 1033.8 mL (18.6 mL/kg) albumin could be saved. The other 3 adult patients did not receive more than 1000 mL of HES 130/0.4. All pediatric patients received approximately 50 mL/kg of HES 130/0.4;for these patients an average amount of 39.9 mL/kg body weight albumin could be saved. The majority of adult patients, and all pediatric patients were hemodynamically stable at all 3 time points. The observed changes of the assessed laboratory parameters including hematological and coagulation parameters or in any other safety parameter determined did not reveal any safety concern related to the administration of 6% HES 130/0.4 up to doses of 50 mL/kg body weight. Conclusion: The study results indicate that 6% HES 130/0.4 has a reliable volume effect, could contribute to significant human albumin savings and was safe and well tolerated up to a maximum dose of 50 mL/kg body weight in adult and pediatric patients undergoing major elective surgery. 展开更多
关键词 High DOSE Volume Effect SAFETY 6% Hydroxyethyl STARCH 130/0.4 ELECTIVE Surgery multi-center Study
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SOPA:Source Routing Based Packet-Level Multi-Path Routing in Data Center Networks
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作者 LI Dan LIN Du +1 位作者 JIANG Changlin Wang Lingqiang 《ZTE Communications》 2018年第2期42-54,共13页
Many "rich - connected" topologies with multiple parallel paths between smwers have been proposed for data center networks recently to provide high bisection bandwidth, but it re mains challenging to fully utilize t... Many "rich - connected" topologies with multiple parallel paths between smwers have been proposed for data center networks recently to provide high bisection bandwidth, but it re mains challenging to fully utilize the high network capacity by appropriate multi- path routing algorithms. As flow-level path splitting may lead to trafl'ic imbalance between paths due to flow- size difference, packet-level path splitting attracts more attention lately, which spreads packets from flows into multiple available paths and significantly improves link utilizations. However, it may cause packet reordering, confusing the TCP congestion control algorithm and lowering the throughput of flows. In this paper, we design a novel packetlevel multi-path routing scheme called SOPA, which leverag- es OpenFlow to perform packet-level path splitting in a round- robin fashion, and hence significantly mitigates the packet reordering problem and improves the network throughput. Moreover, SOPA leverages the topological feature of data center networks to encode a very small number of switches along the path into the packet header, resulting in very light overhead. Compared with random packet spraying (RPS), Hedera and equal-cost multi-path routing (ECMP), our simulations demonstrate that SOPA achieves 29.87%, 50.41% and 77.74% higher network throughput respectively under permutation workload, and reduces average data transfer completion time by 53.65%, 343.31% and 348.25% respectively under production workload. 展开更多
关键词 data center networks multi-path routing path splitting
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基于Multi-Agent的铁路物流中心信息系统模型 被引量:2
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作者 蒲光华 《物流工程与管理》 2009年第12期81-83,共3页
分析了铁路物流中心信息系统建设的重要性,结合人工智能领域的Agent技术,提出了基于Multi-Agent的铁路物流中心信息系统模型,并且分析了该系统的运行机制。该系统具有一定的智能性、易重构性以及较强的交互能力,为铁路物流中心信息系统... 分析了铁路物流中心信息系统建设的重要性,结合人工智能领域的Agent技术,提出了基于Multi-Agent的铁路物流中心信息系统模型,并且分析了该系统的运行机制。该系统具有一定的智能性、易重构性以及较强的交互能力,为铁路物流中心信息系统的进一步开发提供了一定的理论依据。 展开更多
关键词 铁路物流中心信息系统 AGENT 系统模型 multi-AGENT系统
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Selection Method of Multi-Objective Problems Using Genetic Algorithm in Motion Plan of AUV 被引量:3
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作者 ZHANG Ming-jun , ZHENG Jin-xing , ZHANG Jing College of Mechanical and Electrical Engineering, Harbin Engineering University, Harbin 150001 ,China College of Computer and Information Science, Harbin Engineering University, Harbin 150001 , China 《Journal of Marine Science and Application》 2002年第1期81-86,共6页
To research the effect of the selection method of multi-objects genetic algorithm problem on optimizing result, thismethod is analyzed theoretically and discussed by using an autonomous underwater vehicle(AUV) as an o... To research the effect of the selection method of multi-objects genetic algorithm problem on optimizing result, thismethod is analyzed theoretically and discussed by using an autonomous underwater vehicle(AUV) as an object. A changingweight vtlue method is put forward and a selection formula is modified. Some experiments were implemented on an AUV.TwinBurger. The results shows that this method is effective and feasible. 展开更多
关键词 AUV multi - objective optimization GENETIC algorithm SELECTION method
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Multi-features Based Approach for Moving Shadow Detection 被引量:4
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作者 周宁 周曼丽 +1 位作者 许毅平 方宝红 《Journal of Donghua University(English Edition)》 EI CAS 2004年第6期76-80,共5页
In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving... In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence. 展开更多
关键词 MOVING SHADOW detection multi - features MOVING OBJECT DETECTION
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:39
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作者 Xiang-Qun Cui Yong-Heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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融合XGBoost和Multi-GRU的数据中心服务器能耗优化算法 被引量:5
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作者 申明尧 韩萌 +2 位作者 杜诗语 孙蕊 张春砚 《计算机应用》 CSCD 北大核心 2022年第1期198-208,共11页
随着云计算技术的快速发展,数据中心的数量大幅增加,随之而来的能源消耗问题逐渐成为一个研究热点。针对服务器能耗优化问题,提出了一种融合极限梯度提升(XGBoost)和多个门控循环单元(Multi-GRU)的数据中心服务器能耗优化(ECOXG)算法。... 随着云计算技术的快速发展,数据中心的数量大幅增加,随之而来的能源消耗问题逐渐成为一个研究热点。针对服务器能耗优化问题,提出了一种融合极限梯度提升(XGBoost)和多个门控循环单元(Multi-GRU)的数据中心服务器能耗优化(ECOXG)算法。首先利用Linux终端监控命令和功耗仪收集服务器各部件的资源占用信息和能耗等数据,并对其进行数据预处理来得到资源利用率。其次将资源利用率串联构造成向量形式的时间序列,用其训练Multi-GRU负载预测模型,并根据预测结果对服务器进行模拟降频,以得到降频后的负载数据。然后将服务器的资源利用率与相同时刻的能耗数据相结合,并用其训练XGBoost能耗预测模型。最后将降频后的负载数据输入到训练后的XGBoost模型中,从而预测出降频后的服务器能耗。在6台物理服务器实际资源利用率数据上的实验表明,与卷积神经网络(CNN)、长短期记忆(LSTM)网络、CNN-GRU和CNN-LSTM模型相比,ECOXG算法在均方根误差(RMSE)上分别降低了50.9%、31.0%、32.7%、22.9%;同时,与LSTM、CNN-GRU和CNN-LSTM模型相比,ECOXG算法在训练时间上分别节省了43.2%、47.1%、59.9%。实验结果表明,ECOXG算法能够在服务器能耗预测和能耗优化方面提供一定的理论基础,且在准确性和运行效率方面明显优于对比算法。此外,模拟降频后的服务器能耗已明显低于真实能耗,且在服务器的利用率较低时降耗效果显著。 展开更多
关键词 数据中心 能耗优化 负载 极限梯度提升 多个门控循环单元
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Building and application of multipath model for meter-wave radar in elevation estimation 被引量:1
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作者 陈迪 沈一鹰 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第6期741-745,共5页
A research is done for multipath effects of low-angle tracking in meter-wave radar,and the theory of multi-scattering centers of complex target is discussed as well as the character of reflected echoes.This points out... A research is done for multipath effects of low-angle tracking in meter-wave radar,and the theory of multi-scattering centers of complex target is discussed as well as the character of reflected echoes.This points out that the distribution and scattering properties of scattering centers are the prime reasons which cause the variation of multipath effects,and all the changes of position,motion and attitude of the target can influence the multipath effects.By building of multipath model for multi-scattering centers for target,the analysis above is verified and a new method of elevation estimation for low-angle target is presented.The new method uses canceling vectors obtained by searching to cancel reflected waves in echoes and reduce the influence of reflected components,which can improve the accuracy of elevation estimation of low-angle target and the performance of low-angle tracking in meter-wave radar.Experimental results verify the availability of the method. 展开更多
关键词 multi-scattering centers multipath model target elevation estimation
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Virtual 5G Network Embedding in a Heterogeneous and Multi-Domain Network Infrastructure 被引量:6
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作者 Cunqian Yu Weigang Hou +2 位作者 Yingying Guan Yue Zong Pengxing Guo 《China Communications》 SCIE CSCD 2016年第10期29-43,共15页
The pursuit of the higher performance mobile communications forces the emergence of the fifth generation mobile communication(5G). 5G network, integrating wireless and wired domain, can be qualified for the complex vi... The pursuit of the higher performance mobile communications forces the emergence of the fifth generation mobile communication(5G). 5G network, integrating wireless and wired domain, can be qualified for the complex virtual network work oriented to the cross-domain requirement. In this paper, we focus on the multi-domain virtual network embedding in a heterogeneous 5G network infrastructure, which facilitates the resource sharing for diverse-function demands from fixed/mobile end users. We proposed the mathematical ILP model for this problem.And based on the layered-substrate-resource auxiliary graph and an effective six-quadrant service-type-judgment method, 5G embedding demands can be classified accurately to match different user access densities. A collection of novel heuristic algorithms of virtual 5G network embedding are proposed. A great deal of numerical simulation results testified that our algorithm performed better in terms of average blocking rate, routing latency and wireless/wired resource utilization, compared with the benchmark. 展开更多
关键词 5G virtual network embedding heterogeneous and multi-domain infrastructure wireless channel capacity data center
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OPTIMIZING DESIGN OF MECHANICAL SELF-CENTERING DEVICE FOR SUSPENSION HEIGHT 被引量:2
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作者 CAO Min ZHANG Yongchao YU Fan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第6期69-75,共7页
Firstly, in view of the respective defects of existing self-centering devices for vehicle suspension height, the design scheme of the proposed mechanical self-centering device for suspension height is described. Takin... Firstly, in view of the respective defects of existing self-centering devices for vehicle suspension height, the design scheme of the proposed mechanical self-centering device for suspension height is described. Taking the rear suspension of a certain light bus as a research example, the structures and parameters of the novel device are designed and ascertained. Then, the road excitation models, the performance evaluation indexes and the half-vehicle model are built, the simulation outputs of time and frequency domain are obtained with the road excitations of random and pulse by using MATLAB/Simulink software. So the main characteristics of the self-centering suspension are presented preliminarily. Finally, a multi-objective parameter design optimization model for the self-centering device is built by weighted sum approach, and optimal solution is obtained by adopting complex approach. The relevant choosing-type parameters for self-centering device components are deduced by using discrete variable optimal method, and the optimal results are verified and analyzed. So the performance potentials of the self-centering device are exerted fully in condition of ensuring overall suspension performances. 展开更多
关键词 Suspension height SELF-centerING Vehicle height adjustment Optimizing design multi-objective optimization
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A Study on Comprehensive Modeling for Errors in on-line Measuring System of Machining Center 被引量:1
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作者 Liu Libing Zhang Qing(Tianjin University, Tianjin (300072) P. R. of ChinaZap Hongmei Yun Jintian)(Hebei University Of Technology, Tianjin (300130) P. R. of China) 《河北工业大学学报》 CAS 1997年第A01期14-22,共9页
Based on the theory of multi-body system (MBS), bine’s and huston’s methods are applied to an on-line measuring system of machining center in this paper. Through the study on modeling technique, the comprehensive mo... Based on the theory of multi-body system (MBS), bine’s and huston’s methods are applied to an on-line measuring system of machining center in this paper. Through the study on modeling technique, the comprehensive model for errors calculation in an on-line measuring System of machining center have been built for the first time. Using this model, the errors can be compensated by soft.ware and the measuring accuracy can be enhanced without any more inveSt. This model can be used in all kinds of machining center. 展开更多
关键词 MACHINING center ON-LINE MEASURING multi-Body System (MBS) Model
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MTSS: multi-path traffic scheduling mechanism based on SDN 被引量:2
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作者 XU Xiaolong CHEN Yun +1 位作者 HU Liuyun KUMAR Anup 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第5期974-984,共11页
Large-scale and diverse businesses based on the cloud computing platform bring the heavy network traffic to cloud data centers.However,the unbalanced workload of cloud data center network easily leads to the network c... Large-scale and diverse businesses based on the cloud computing platform bring the heavy network traffic to cloud data centers.However,the unbalanced workload of cloud data center network easily leads to the network congestion,the low resource utilization rate,the long delay,the low reliability,and the low throughput.In order to improve the utilization efficiency and the quality of services(QoS)of cloud system,especially to solve the problem of network congestion,we propose MTSS,a multi-path traffic scheduling mechanism based on software defined networking(SDN).MTSS utilizes the data flow scheduling flexibility of SDN and the multi-path feature of the fat-tree structure to improve the traffic balance of the cloud data center network.A heuristic traffic balancing algorithm is presented for MTSS,which periodically monitors the network link and dynamically adjusts the traffic on the heavy link to achieve programmable data forwarding and load balancing.The experimental results show that MTSS outperforms equal-cost multi-path protocol(ECMP),by effectively reducing the packet loss rate and delay.In addition,MTSS improves the utilization efficiency,the reliability and the throughput rate of the cloud data center network. 展开更多
关键词 CLOUD data center software defined networking(SDN) LOAD balancing multi-PATH transmission OpenFlow
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多代理(Multi-Agent)技术在电力系统控制中的应用 被引量:3
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作者 廖恩荣 《机械制造与自动化》 2013年第2期159-163,共5页
多代理系统理论是设计和实现复杂软件系统和控制系统的新途径,它因适用条件与电力系统的特征几乎完全吻合而受到众多学者的关注,但在电力系统中仍处在理论和应用的边缘。在介绍多代理系统理论基本特点的基础上,综述了其在电力系统控制... 多代理系统理论是设计和实现复杂软件系统和控制系统的新途径,它因适用条件与电力系统的特征几乎完全吻合而受到众多学者的关注,但在电力系统中仍处在理论和应用的边缘。在介绍多代理系统理论基本特点的基础上,综述了其在电力系统控制中心、继电保护系统、电压无功控制以及暂态稳定紧急控制等领域应用的国内外研究现状,展望了最具实用化潜力与基础较完备的分支,以推动多代理技术在这些领域的广泛应用。 展开更多
关键词 多代理系统 电力系统控制中心 继电保护系统 电压无功控制 暂态稳定紧急控制
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