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Metadata Feedback and Utilization for Data Deduplication Across WAN

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Journal of Computer Science & Technology 2016年第3期31卷 604-623页

作者： Bing Zhou jiang-Tao wen State Key Laboratory on Intelligent Technology and Systems Tsinghua University Beijing 100084 China Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100084 China Department of Computer Science and Technology Tsinghua University Beijing 100084 China

Data deduplication for file communication across wide area network （WAN） in the applications such as file synchronization and mirroring of cloud environments usually achieves significant bandwidth saving at the cost of significant time overheads of data deduplication. The time overheads include the time required for data deduplication at two geographi- cally distributed nodes （e.g., disk access bottleneck） and the duplication query/answer operations between the sender and the receiver, since each query or answer introduces at least one round-trip time （RTT） of latency. In this paper, we present a data deduplication system across WAN with metadata feedback and metadata utilization （MFMU）, in order to harness the data deduplication related time overheads. In the proposed MFMU system, selective metadata feedbacks from the receiver to the sender are introduced to reduce the number of duplication query/answer operations. In addition, to harness the metadata related disk I/O operations at the receiver, as well as the bandwidth overhead introduced by the metadata feedbacks, a hysteresis hash re-chunking mechanism based metadata utilization component is introduced. Our experimental results demonstrated that MFMU achieved an average of 20%~40% deduplication acceleration with the bandwidth saving ratio not reduced by the metadata feedbacks, as compared with the ＂baseline＂ content defined chunking （CDC） used in LBFS （Low-bandwith Network File system） and exiting state-of-the-art Bimodal chunking algorithms based data deduplication solutions.

关键词： data deduplication wide area network (WAN) metadata feedback metadata utilization

Improving Metadata Caching Efficiency for Data Deduplication via In-RAM Metadata Utilization

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Journal of Computer Science & Technology 2016年第4期31卷 805-819页

We describe a data deduplication system for backup storage of PC disk images, named in-RAM metadata utilizing deduplication （IRwMUD）. In-RAM hash granularity adaptation and miniLZO based data compression are firstly proposed to reduce the in-RAM metadata size and thereby reduce the space overheads required by the in-RAM metadata caches. Secondly, an in-RAM metadata write cache, as opposed to the traditional metadata read cache, is proposed for further reducing metadata-related disk I/O operations and improving deduplication throughput. During deduplication, the metadata write cache is managed following the LRU caching policy. For each manifest that is hit in the metadata write cache, an expensive manifest reloading operation from the disk is avoided. After deduplieation, all the manifests in the metadata write cache are cleared and stored on the disk. Our experimental results using 1.5 TB real-world disk image dataset show that I） IR-MUD achieved about 95% size reduction for the deduplication metadata, with a small time overhead introduced, 2） when the metadata write cache was not utilized, with the same RAM space size for the metadata read cache, IR-MUD achieved a 400% higher RAM hit ratio and a 50% higher deduplication throughput, as compared with the classic Sparse Indexing deduplication system where no metadata utilization approaches are utilized, and 3） when the metadata write cache was utilized and enough RAM space was available, IR-MUD achieved a 500% higher RAM hit ratio compared with Sparse Indexing and a 70% higher deduplication throughput compared with IR-MUD with only a single metadata read cache. The in-RAM metadata harnessing and metadata write caching approaches of IR-MUD can be applied in most parallel deduplication systems for improving metadata caching efficiency.

关键词： data deduplication cache metadata utilization

Deep Multimodal Reinforcement Network with Contextually GuidedRecurrent Attention for Image Question Answering

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Journal of Computer Science & Technology 2017年第4期32卷 738-748页

作者： Ai-wen jiang Bo Liu Ming-wen Wang College of Computer and Information Engineering Jiangxi Normal University Nanchang 330022 China College of Computer Science and Software Engineering Auburn University Auburn AL36849 U.S.A.

Image question answering (IQA) has emerged as a promising interdisciplinary topic in computer vision and natural language processing fields. In this paper, we propose a contextually guided recurrent attention model for solving the IQA issues. It is a deep reinforcement learning based multimodal recurrent neural network. Based on compositional contextual information, it recurrently decides where to look using reinforcement learning strategy. Different from traditional 'static' soft attention, it is deemed as a kind of 'dynamic' attention whose objective is designed based on reinforcement rewards purposefully towards IQA. The finally learned compositional information incorporates both global context and local informative details, which is demonstrated to benefit for generating answers. The proposed method is compared with several state-of-the-art methods on two public IQA datasets, including COCO-QA and VQA from dataset MS COCO. The experimental results demonstrate that our proposed model outperforms those methods and achieves better performance.

关键词： image question answering recurrent attention deep reinforcement learning multimodal recurrent neural network multimodal fusion

Improved de-interleaving algorithm of radar pulses based on dual fuzzy vigilance ART

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Journal of Systems Engineering and Electronics 2020年第2期31卷 303-311页

作者： jiang wen FU Xiongjun CHANG Jiayun School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

As a core part of the electronic warfare(EW) system,de-interleaving is used to separate interleaved radar signals. The de-interleaving algorithm based on the fuzzy adaptive resonance theory(fuzzy ART) is plagued by the problems of premature saturation and performance improving dilemma. This study proposes a dual fuzzy vigilance ART(DFV-ART) algorithm to address these problems and make the following improvements. Firstly, a correction method is introduced to prevent the network from prematurely saturating;then, the fuzzy vigilance models(FVM) are constructed to replace the conventional vigilance parameter, reducing the error probability in the overlapping region;finally, a dual vigilance mechanism is introduced to solve the performance improving dilemma. Simulation results show that the proposed algorithm could improve the clustering accuracy(quantization error dropped60%) and the de-interleaving performance(clustering quality increased by 10%) while suppressing the excessive proliferation of categories.

关键词： fuzzy adaptive resonance theory(fuzzy ART) deinterleaving dual vigilance mechanism

An ECR-PCR rule for fusion of evidences defined on a non-exclusive framework of discernment

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Chinese Journal of Aeronautics 2022年第8期35卷 179-192页

作者： Xinyang DENG Yebi CUI wen jiang School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China

In the research of uncertain information processing,Dempster-Shafer Theory(DST)provides a framework for dealing with uncertain information,where evidence is defined on a Frame of Discernment(FOD)consisting of mutually exclusive ***,the requirement of exclusiveness on FOD sometimes is not satisfied,as shown in Dezert-Smarandache Theory(DSm T),a derivative of *** DSm T,the non-exclusiveness is expressed by propositions’intersection and the fusion of evidence is realized through a Proportional Conflict Redistribution(PCR)*** order to handle non-exclusive FODs,a new framework called D Number Theory(DNT)has been proposed recently,which quantifies the non-exclusive degree between propositions different from DSm *** previous studies,an Exclusive Conflict Redistribution(ECR)rule has been designed in DNT to implement the fusion of evidence defined on a non-exclusive FOD,but there are some deficiencies in the ECR *** this paper,a new rule called ECR-PCR rule is proposed by combining the ECR and PCR rules to better implement the fusion of evidence defined on a nonexclusive *** the proposed rule,the definition of conflict utilizes the idea of ECR’s exclusive conflict,and the disposal of conflict is following the idea of PCR’s proportional *** of the ECR-PCR rule are *** effectiveness of the proposed new rule is verified through numerical examples and applications,in comparison with other fusion methods.

关键词： D number theory Dempster-Shafer theory Evidence combination Non-exclusiveness Proportional Conflict Redistribution rule Information fusion

MODEL ANALYSIS AND PARAMETER EXTRACTION FOR MOS CAPACITOR INCLUDING QUANTUM MECHANICAL EFFECTS

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Journal of Computational Mathematics 2006年第3期24卷 401-411页

作者： Hai-yan jiang Ping-wen Zhang LMAM CCSE and School of Mathematical Sciences.Peking University Beijing 100871 China

The high frequency CV curves of MOS capacitor have been studied. It is shown that semiclassical model is a good approximation to quantum model and approaches to classical model when the oxide layer is thick. This conclusion provides us an efficient （semiclassical） model including quantum mechanical effects to do parameter extraction for ultrathin oxide device. Here the effective extracting strategy is designed and numerical experiments demonstrate the validity of the strategy.

关键词： Poisson Equation SchrSdinger Equation MOS Capacitor Quantum Effect,Sensitivity Parameter Extraction.

Health Education in the Healthy China Initiative 2019−2030

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China CDC weekly 2021年第4期3卷 78-80页

作者： Zhuojun jiang wen jiang Media Integration and Mass Communication Department China Population Communication CenterBeijingChina

As the first of 15 Healthy China initiatives,the Health Education Initiative has the crucially important goal of improving citizens’health *** are two key activities in the initiative for improving health *** first is to establish a mechanism for dissemination of health sciences knowledge through development of national and provincial databases of health sciences expertise and a national resource of accessible health *** second is to establish a health education and health promotion performance evaluation mechanism for medical institutions and medical *** this paper,we analyzed the content and strategies of these two health educational activities.

关键词： promotion education knowledge

Distributed Power Control in Cooperative Cognitive Ad hoc Networks

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International Journal of Automation and computing 2014年第4期11卷 412-417页

作者： wen-jiang Feng Rong jiang Guo-Ling Liu College of Communication Engineering Chongqing University

In this paper, a relay selection strategy and distributed power control algorithm are proposed for the underlay spectrum sharing mode based cooperative cognitive ad hoc network with energy-limited users. The study aims to minimize the total power consumption of cooperative cognitive ad hoc network while ensuring the quality of service(QoS) requirement of cognitive user and keeping the interference to primary user below interference tolerance. The power control problem is transformed into a convex optimization problem. Based on Lagrange dual decomposition theory, a gradient iterative algorithm is constructed to search for the optimal solution and complete distributed power optimization. Simulation results show that the algorithm converges fast and reduces transmit power of cognitive users effectively while guaranteeing the QoS requirement.

关键词： Ad hoc network cooperative communication power control cognitive system convex optimization

Synthesis of CdSe quantum dots via paraffin liquid and oleic acid

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第1期9卷 133-136页

作者： Yu-feng LIAO wen-jiang LI Centre for Optical and Electromagnetic Research State Key Laboratory for Modern Optical Instrumentation Joint Research Center of Photonics of the Royal Institute of Technology （Sweden） and Zhejiang University Zhejiang University Hangzhou 310058 China

This paper reported an efficient and rapid method to produce highly monodispersed CdSe quantum dots (QDs), in which the traditional trioctylphosphine oxide (TOPO) was replaced by paraffin liquid as solvent and oleic acid as the reacting media. The experimental conditions and the properties of QDs had been studied in detail. The resulting samples were confirmed of uniform size distribution with transmission electronic microscopy (TEM), while UV-vis absorption and photoluminescence (PL) spectra clearly indicated that such synthesized QDs had good fluorescence properties.

关键词： CdSe Synthesis Quantum dots (QDs) Fluorescence