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SplitPass： A Mutually Distrusting Two-Party Password Manager

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Journal of Computer Science & Technology 2018年第1期33卷 98-115页

作者： yu-Tao Liu Dong Du yu-bin Xia Hai-Bo Chen bin-yu zang Zhenkai Liang Institute of Parallel and Distributed Systems Shanghai Jiao Tong University Shanghai 200240 China School of Computing National University of Singapore Singapore 117417 Singapore

Using a password manager is known to be more convenient and secure than not using one, on the assmnption that the password manager itself is safe. However recent studies show that most popular password managers have security vulnerabilities that may be fooled to leak passwords without users＇ awareness. In this paper, we propose a new password manager, SplitPass, which vertically separates both the storage and access of passwords into two mutually distrusting parties. During login, all the parties will collaborate to send their password shares to the web server, but none of these parties will ever have the complete password, which significantly raises the bar of a successful attack to compromise all of tile parties. To retain transparency to existing applications and web servers, SplitPass seamlessly splits the secure sockets layer （SSL） and transport layer security （TCP） sessions to process on all parties, and makes the joining of two password shares transparent to the web servers. We have implemented SplitPass using an Android phone and a cloud assistant and evaluated it using 100 apps from top free apps in the Android official market. The evaluation shows that SplitPass securely protects users＇ passwords, while incurring little performance overhead and power consumption.

关键词： password manager privacy protection mobile-cloud system

Revisiting Persistent Indexing Structures on Intel Optane DCPersistent Memory

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Journal of Computer Science & Technology 2021年第1期36卷 140-157页

作者： Heng Bu Ming-Kai Dong Ji-Fei Yi bin-yu zang Hai-Bo Chen Institute of Parallel and Distributed Systems Shanghai Jiao Tong UniversityShanghai 200240China

Persistent indexing structures are proposed in response to emerging non-volatile memory(NVM)to provide high performance yet durable ***,due to the lack of real NVM hardware,many prior persistent indexing structures were evaluated via emulation,which varies a lot across different setups and differs from the real ***,Intel has released its Optane DC Persistent Memory Module(PMM),which is the first production-ready *** this paper,we revisit popular persistent indexing structures on PMM and conduct comprehensive evaluations to study the performance differences among persistent indexing structures,including persistent hash tables and persistent *** to the evaluation results,we find that Cacheline-Conscious Extendible Hashing(CCEH)achieves the best performance among all evaluated persistent hash tables,and Failure-Atomic ShifT B+-Tree(FAST)and Write Optimal Radix Tree(WORT)perform better than other ***,we find that the insertion performance of hash tables is heavily influenced by data locality,while the insertion latency of trees is dominated by the flush *** also uncover that no existing emulation methods accurately simulate PMM for all the studied data ***,we provide three suggestions on how to fully utilize PMM for better performance,including using clflushopt/clwb with sfence instead of clflush,flushing continuous data in a batch,and avoiding data access immediately after it is flushed to PMM.

关键词： persistent memory data structure performance Intel Optane DC persistent memory module(PMM)

Scaling out NUMA-Aware Applications with RDMA-Based Distributed Shared Memory

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Journal of Computer Science & Technology 2019年第1期34卷 94-112页

作者： Yang Hong Yang Zheng Fan Yang bin-yu zang Hai-bing Guan Hai-Bo Chen Shanghai Key Laboratory for Scalable Computing Systems Shanghai Jiao Tong UniversityShanghai 200240China

The multicore evolution has stimulated renewed interests in scaling up applications on shared-memory multiprocessors,significantly improving the scalability of many *** the scalability is limited within a single node;therefore programmers still have to redesign applications to scale out over multiple *** paper revisits the design and implementation of distributed shared memory (DSM)as a way to scale out applications optimized for non-uniform memory access (NUMA)architecture over a well-connected *** paper presents MAGI,an efficient DSM system that provides a transparent shared address space with scalable performance on a cluster with fast network *** is unique in that it presents a NUMA abstraction to fully harness the multicore resources in each node through hierarchical synchronization and memory *** also exploits the memory access patterns of big-data applications and leverages a set of optimizations for remote direct memory access (RDMA)to reduce the number of page faults and the cost of the coherence *** has been implemented as a user-space library with pthread-compatible interfaces and can run existing multithreaded applications with minimized *** deployed MAGI over an 8-node RDMA-enabled *** evaluation shows that MAGI achieves up to 9.25:4 speedup compared with an unoptimized implementation,leading to a sealable performance for large-scale data-intensive applications.

关键词： distributed shared memory (DSM) scalability multieore evolution non-uniform memory access (NUMA) remote direct memory access (RDMA)

Optimistic Transaction Processing in Deterministic Database

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Journal of Computer Science & Technology 2020年第2期35卷 382-394页

作者： Zhi-yuan Dong Chu-Zhe Tang Jia-Chen Wang Zhao-Guo Wang Hai-Bo Chen bin-yu zang Institute of Parallel and Distributed Systems Shanghai Jiao Tong UniversityShanghai 200240China

Deterministic databases can improve the performance of distributed workload by eliminating the distributed commit protocol and reducing the contention ***,the current deterministic scheme does not consider the performance scalability within a single *** this paper,we describe a scalable deterministic concurrency control,Deterministic and Optimistic Concurrency Control(DOCC),which is able to scale the performance both within a single node and across multiple *** performance improvement comes from enforcing the determinism lazily and avoiding read-only transaction blocking the *** evaluation shows that DOCC achieves 8x performance improvement than the popular deterministic database system,Calvin.

关键词： deterministic database concurrency control scalability

Mercury: Combining Performance with Dependability Using Self-Virtualization

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Journal of Computer Science & Technology 2012年第1期27卷 92-104页

作者： Hai-Bo Chen Feng-Zhe Zhang Rong Chen bin-yu zang Pen-Chung Yew School of Software Shanghai Jiaotong UniversityShanghai 200240China Parallel Processing Institute Fudan UniversityShanghai 201203China Institute of Information Science Academia SinicaTaipeiChina

Virtualization has recently gained popularity largely due to its promise in increasing utilization, improving availability and enhancing security. Very often, the role of computer systems needs to change as the business environment changes. Initially, the system may only need to host one operating system and seek full execution speed. Later, it may be required to add other functionalities such as allowing easy software/hardware maintenance, surviving system failures and hosting multiple operating systems. Virtualization allows these functionalities to be supported easily and effectively. However, virtualization techniques generally incur non-negligible performance penalty. Fortunately, many virtualization- enabled features such as online software/hardware maintenance and fault tolerance do not require virtualization standby all the time. Based on this observation, this paper proposes a technique, called Self-virtualization, which provides the operating system with the capability to turn on and off virtualization on demand, without disturbing running applications. This technique enables computer systems to reap most benefits from virtualization without sacrificing performance. This paper presents the design and implementation of Mercury, a working prototype based on Linux and Xen virtual machine monitor. The performance measurement shows that Mercury incurs very little overhead： about 0.2 ms on 3 GHz Xeon CPU to complete a mode switch, and negligible performance degradation compared to Linux.

关键词： dependability performance self-virtualization dynamic virtualization

Bipartite-Oriented Distributed Graph Partitioning for Big Learning

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Journal of Computer Science & Technology 2015年第1期30卷 20-29页

作者：陈榕施佳鑫陈海波臧斌宇 Shanghai Key Laboratory of Scalable Computing and Systems Institute of Parallel and Distributed Systems Shanghai Jiao Tong University Shanghai 200240 China

Many machine learning and data mining （MLDM] problems like recommendation, topic modeling, and medical diagnosis can be modeled as computing on bipartite graphs. However, inost distributed graph-parallel systems are oblivious to the unique characteristics in such graphs and existing online graph partitioning algorithms usually cause excessive repli- cation of vertices as well as significant pressure on network communication. This article identifies the challenges and oppor- tunities of partitioning bipartite graphs for distributed MLDM processing and proposes BiGraph, a set of bipartite-oriented graph partitioning algorithms. BiGraph leverages observations such as the skewed distribution of vertices, discriminated computation load and imbalanced data sizes between the two subsets of vertices to derive a set of optimal graph partition- ing algorithms that result in minimal vertex replication and network communication. BiGraph has been implemented on PowerGraph and is shown to have a performance boost up to 17.75X （from 1.16X） for four typical MLDM algorithnls, due to reducing up to 80% vertex replication, and up to 96% network traffic.

关键词： bipartite graph graph partitioning graph-parallel system

Interfacial behaviors between ZG13Cr9Mo1VNbN stainless steel and chromite sand

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Journal of Iron and Steel Research International 2025年第1期32卷 129-143页

作者： Shi-sen Li Xi-min zang Ji-lin Chen Jie Yang yu-an Jing Zhi-ying Wang Ling-zhong Kong School of Materials and Metallurgy University of Science and Technology LiaoningAnshan114051LiaoningChina School of Material Science and Engineering Shenyang University of TechnologyShenyang110870LiaoningChina Central Iron and Steel Research Institute Co. Ltd.Beijing100081China Xingtai Iron and Steel Co. Ltd.Xingtai054027HebeiChina

To elucidate the formation mechanisms of burn-on sand and metal penetration during sand casting,some laboratory experiments were carried out at different temperatures(1813,1833,1853,and 1873 K)and holding time(20,40,60,and 90 min)to simulate the interaction between ZG13Cr9Mo1VNbN stainless steel and chromite *** results demonstrate that the defects primarily consist of a mixture of the liquid phase,chromite,and *** main components of the liquid phase are SiO_(2),MnO,MgO,Cr_(2)O_(3),FeO,and Al_(2)O_(3),and the formation of Cr_(2)O_(3)through interfacial redox reactions has been *** presence of a liquid phase plays a pivotal role in influencing burn-on sand and metal *** reactions are prioritized,with burn-on sand maintaining a predominant *** the liquid phase quantity within the sand escalates,there is a corresponding incremental rise in the incidence of metal *** a minimal presence of the silicon element in steel can impact the liquid phase’s ***,the decomposition or dissolution of chromite sand is a significant factor in the development of burn-on sand and metal ***,a thorough investigation into the conditions and contributing factors of this phenomenon is essential for its effective management and mitigation.

关键词： Heat-resistant steel Chromite sand Interfacial reaction Burn-on sand Metal penetration Temperature Holding time

Recent Advances in Artificial Sensory Neurons:Biological Fundamentals,Devices,Applications,and Challenges

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Nano-Micro Letters 2025年第3期17卷 168-216页

作者： Shuai Zhong Lirou Su Mingkun Xu Desmond Loke bin yu Yishu Zhang Rong Zhao Guangdong Institute of Intelligence Science and Technology HengqinZhuhai 519031People’s Republic of China College of Integrated Circuits Zhejiang UniversityHangzhou 3112000People’s Republic of China ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 310027People’s Republic of China Department of Science Mathematics and TechnologySingapore University of Technology and DesignSingapore 487372Singapore Department of Precision Instruments Tsinghua UniversityBeijing 100084People’s Republic of China Center for Brain‑Inspired Computing Research Tsinghua UniversityBeijing 100084People’s Republic of China IDG/McGovern Institute for Brain Research Tsinghua UniversityBeijing 100084People’s Republic of China

Spike-based neural networks,which use spikes or action potentialsto represent information,have gained a lot of attention because of their high energyefficiency and low power *** fully leverage its advantages,convertingthe external analog signals to spikes is an essential *** including analog-to-digital converters or ring oscillators,and sensorssuffer from high power and area *** efforts are devoted to constructingartificial sensory neurons based on emerging devices inspired by the biologicalsensory *** can simultaneously perform sensing and spike conversion,overcoming the deficiencies of traditional sensory *** review summarizesand benchmarks the recent progress of artificial sensory *** starts with thepresentation of various mechanisms of biological signal transduction,followed bythe systematic introduction of the emerging devices employed for artificial ***,the implementations with different perceptual capabilitiesare briefly outlined and the key metrics and potential applications are also ***,we highlight the challenges and perspectives for the future development of artificial sensory neurons.

关键词： Artificial intelligence Emerging devices Artificial sensory neurons Spiking neural networks Neuromorphic sensing

Solar trough receiver with V-grooved light traps for efficiency improvement

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Science China(Technological Sciences) 2025年第1期68卷 142-152页

作者： bin LIU Qing LI yu QIU School of Energy Science and Engineering Central South UniversityChangsha 410083China

Parabolic trough collector is a promising technology for both domestic and industrial heat *** enhance the collector efficiency,a modified trough receiver with dozens of V-grooved light traps incorporated into its lower-half absorber was *** assessing the performance of this receiver,a solar-thermal-stress coupled model was *** this model,firstly,the effects of the V-grooved light traps were *** results reveal that,compared to the conventional trough receiver,the modified trough receivers equipped with different traps can reduce their optical losses by 81.9-138.0 Wm^(-1)(i.e.,15.0%-25.2%),improving their optical efficiencies by 1.60%-2.69%.However,these traps also result in increased thermal loss from the ***,there is no single optimal modified trough receiver that consistently outperforms all other receivers across all possible ***,the MTR30-3 and MTR60-3 receivers emerge as the optimized choices due to their better solar-thermal ***,performance evaluation reveals that the two optimized receivers can enhance the receiver efficiencies within the typical solar irradiance range by 0.02%-2.65%and 0.05%-1.70%when the inlet fluid temperatures are below 488 and 523 K,***,the collector efficiencies can be improved by 0.02%-2.49%and 0.05%-1.60%,***,thermal stress analysis verifies that the two optimized receivers remain within safe limits under all typical *** that the heating temperature of a typical solar collector for domestic or industrial heat supply is typically below 523 K,the integration of the two optimized receivers has the capability to effectively enhance the overall collector efficiency.

关键词： parabolic trough collector receiver V-grooved light trap solar-thermal-stress coupled model efficiency improvement