检索结果-南通市图书馆

Molecular dynamics study on microscale residual stress of graphene/aluminum nanocomposites by selective laser sintering

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2022年第11期41卷 3677-3683页

作者： xing-Nan hao Xia Liu Department of Engineering Mechanics Beijing University of TechnologyBeijing100124China

The fabrication of graphene/metal matrix composites by selective laser sintering(SLS)technique has been extensively studied;however,the complex micros truc ture and residual stress limit their further ***,the sinterin... 详细信息

关键词： stress residual composites

On Randers Metrics with Isotropic S-Curvature

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2008年第5期24卷 789-796页

作者： Zhong Min SHEN hao xing Department of Mathematics IUPUI Indianapolis IN 46202-3216 USA Department of Mathematics University of Michigan Ann Arbor MI 48109 USA

In this paper, we study a class of Finsler metrics defined by a vector field on a Riemannian space form. We give an explicit formula for those with isotropic S-curvature. This class contains all Randers metrics of con... 详细信息

关键词： Randers metrics S-curvature

Centrifuge and numerical modeling of h-type anti-slide pile reinforced soil-rock mixture slope

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2023年第5期20卷 1441-1457页

作者： ZHANG hao xing hao-feng XUE Dao-rui TANNANT Dwayne Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China School of Urban Construction and Transportation Hefei UniversityHefei 230601China School of Engineering University of British ColumbiaKelowna BC V1V 1V7Canada Guangdong Communication Planning and Design Institute Group Co. Ltd.Guangzhou 510507China

Due to the loose structure,high porosity and high permeability of soil-rock mixture slope,the slope is unstable and may cause huge economic losses and *** h-type anti-slide pile is regarded as an effective means to prevent the instability of soilrock mixture *** this paper,a centrifuge model test was conducted to investigate the stress distribution of the h-type anti-slide pile and the evolution process of soil arching during the loading.A numerical simulation model was built based on the similar relationship between the centrifuge model and the prototype to investigate the influence factors of the pile spacing,anchored depth,and crossbeam stiffness,and some recommendations were proposed for its *** results show that the bending moment distribution of the rear pile exhibits Wshaped,while for the front pile,its distribution resembles *** soil arching evolution process during loading is gradually dissipated from bottom to top and from far to *** the loading,the change of bending moment can be divided into three stages,namely,the stabilization stage,the slow growth stage,and the rapid growth *** engineering projects,the recommended values of the pile spacing,anchored depth,and crossbeam stiffness are 4.0d,2.0d,and 2.0EI,where d and EI are the diameter and bending stiffness of the h-type anti-slide pile respectively.

关键词： Centrifugemodel test Numerical simulation h-type anti-slide pile Soil-rock mixture slop Soil arching

An efficient approach for continuous density queries

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2012年第5期6卷 581-595页

作者： Jie WEN Xiaofeng MENG xing hao Jianliang XU School of Information Renmin University of ChinaBeijing 100872China Department of Computer Science Hong Kong Baptist UniversityHong KongChina

In location-based services, a density query re- turns the regions with high concentrations of moving objects （MOs）. The use of density queries can help users identify crowded regions so as to avoid congestion. Most of the exist- ing methods try very hard to improve the accuracy of query results, but ignore query efficiency. However, response time is also an important concern in query processing and may have an impact on user experience. In order to address this issue, we present a new definition of continuous density queries. Our approach for processing continuous density queries is based on the new notion of a safe interval, using which the states of both dense and sparse regions are dynamically main- tained. Two indexing structures are also used to index candi- date regions for accelerating query processing and improving the quality of results. The efficiency and accuracy of our approach are shown through an experimental comparison with snapshot density queries.

关键词： continuous density queries safe interval query efficiency

Morphological Change and Its Mechanism of Eutectic Silicon for Strontium-Modified Alloy A357

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2004年第1期11卷 47-51页

作者： GUO Jian-ting DU xing-hao Institute of Metal Research CAS

The Y 2O 3-CeO 2-ZrO 2 powders were prepared using a co-precipitation process and the corresponding coatings were prepared by plasma spraying. The results show that an optimal composition exists in Y 2O 3-doped CeO 2-ZrO 2, but not in CeO 2-doped Y 2O 3-ZrO 2. The powders mainly contain tetragonal phase and a trace amount of monoclinic phase. The homogeneity in composition, large agglomerate size, ideal particle size distribution and high flowability were obtained. The as-sprayed coatings are composed of non-transformable tetragonal phase, tz′structure, and resistant to transformation under thermal or mechanical stresses.

关键词： powder coating co-precipitation plasma spraying non-transformable tetragonal phase

Guaranteed Cost Finite-Time Control of Fractional-Order Nonlinear Positive Switched Systems with D-Perturbations via MDADT

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2019年第3期32卷 857-874页

作者： LIU Leipo CAO Xiangyang FU Zhumu SONG Shuzhong xing hao School of Information Engineering Henan University of Science and Technology

This paper is concerned with the problem of guaranteed cost finite-time control of fractionalorder nonlinear positive switched systems (FONPSS) with D-perturbation. Firstly, the proof of the positivity of FONPSS with D-perturbation is given, the definition of guaranteed cost finite-time stability is firstly given in such systems. Then, by constructing linear copositive Lyapunov functions and using the mode-dependent average dwell time (MDADT) approach, a static output feedback controller is constructed, and sufficient conditions are derived to guarantee that the corresponding closed-loop system is guaranteed cost finite-time stable (GCFTS). Such conditions can be easily solved by linear programming. Finally, an example is provided to illustrate the effectiveness of the proposed method.

关键词： Finite-time stability fractional-order nonlinear positive switched systems guaranteed cost control linear programming mode-dependent average dwell time

Optimal Operation of Flexible Distribution Networks for Security Improvement Considering Active Management

在线全文

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2023年第3期9卷 996-1007页

作者： Jia Liu Pingliang Zeng hao xing Yalou Li Qiuwei Wu Department of Automation Hangzhou Dianzi UniversityHangzhou 310018China Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China China Electric Power Research Institute Beijing 100192China Department of Electrical Engineering Technical University of DenmarkKongens Lyngby 2800Denmark

This paper presents a stochastic optimal operation problem of gas turbine integrated distribution networks in the presence of active management schemes,which is formulated as a multi-objective chance-constrained mixed integer nonlinear programming *** control variables are the on-load tap-changer tap position,the power provided by the distributed generation(DG),the DG power factor angle,the load participating in demand side management and the switch *** objectives defined in this paper are to simultaneously minimize the expectation cost and variation coefficient of security *** related to DG output and load fluctuation and fault power restoration under contingencies are also considered in the optimization *** collaboration of normal boundary intersection and the dynamic niche differential evolution algorithm is proposed to handle the optimal operation *** results are presented and demonstrate the effectiveness of the proposed *** with the operation result without the consideration of security,the security-constrained operation can reduce the expectation ***,the proposed optimization is reasonable and valuable.

关键词： Active management flexible distribution networks optimal operation security improvement uncertainties

Efficient Metric All-k-Nearest-Neighbor Search on Datasets Without Any Index

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2016年第6期31卷 1194-1211页

作者： Hai-Da Zhang Zhi-hao xing Lu Chen Yun-Jun Gao College of Computer Science Zhejiang University Hangzhou 310027 China School of Computer Science and Engineering The University of New South Wales Sydney 2052 Australia

An all-k-nearest-neighbor （AkNN） query finds k nearest neighbors for each query object. This problem arises naturally in many areas, such as GIS （geographic information system）, multimedia retrieval, and recommender systems. To support various data types and flexible distance metrics involved in real applications, we study AkNN retrieval in metric spaces, namely, metric AkNN （MAkNN） search. Consider that the underlying indexes on the query set and the object set may not exist, which is natural in many scenarios. For example, the query set and the object set could be the results of other queries, and thus, the underlying indexes cannot be built in advance. To support MAkNN search on datasets without any underlying index, we propose an efficient disk-based algorithm, termed as Partition-Based MAkNN Algorithm （PMA）, which follows a partition-search framework and employs a series of pruning rules for accelerating the search. In addition, we extend our techniques to tackle an interesting variant of MAkNN queries, i.e., metric self-AkNN （MSAkNN） search, where the query set is identical to the object set. Extensive experiments using both real and synthetic datasets demonstrate the effectiveness of our pruning rules and the efficiency of the proposed algorithms, compared with state-of-the-art MAkNN and MSAkNN algorithms.

关键词： all-k-nearest-neighbor search query processing metric space

A New Decentralized Algorithm for Optimal Load Shifting via Electric Vehicles 36

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A New Decentralized Algorithm for Optimal Load Shifting via ...