Journal of Computer Science and Technology最新文献_第8页

Dalea: A Persistent Multi-Level Extendible Hashing with Improved Tail Performance Dalea:具有改进尾部性能的持久多级可扩展散列

IF 1.9 3区计算机科学

Journal of Computer Science and Technology Pub Date : 2023-09-30 DOI: 10.1007/s11390-023-2957-8

Zi-Wei Xiong, De-Jun Jiang, Jin Xiong, Ren Ren

{"title":"Dalea: A Persistent Multi-Level Extendible Hashing with Improved Tail Performance","authors":"Zi-Wei Xiong, De-Jun Jiang, Jin Xiong, Ren Ren","doi":"10.1007/s11390-023-2957-8","DOIUrl":"https://doi.org/10.1007/s11390-023-2957-8","url":null,"abstract":"Persistent memory (PM) promises byte-addressability, large capacity, and durability. Main memory systems, such as key-value stores and in-memory databases, benefit from such features of PM. Due to the great popularity of hashing index in main memory systems, a number of research efforts are made to provide high average performance persistent hashing. However, suboptimal tail performance in terms of tail throughput and tail latency is still observed for existing persistent hashing. In this paper, we analyze major sources of suboptimal tail performance from key design issues of persistent hashing. We identify the global hash structure and concurrency control as remaining explorable design spaces for improving tail performance. We propose Directory-sharing Multi-level Extendible Hashing (Dalea) for PM. Dalea designs ancestor link-based extendible hashing as well as fine-grained transient lock to address the two main sources (rehashing and locking) affecting tail performance. The evaluation results show that, compared with state-of-the-art persistent hashing Dash, Dalea achieves increased tail throughput by 4.1x and reduced tail latency by 5.4x. Moreover, in order to provide design guidelines for improving tail performance, we adopt Dalea as a testbed to identify different impacts of four factors on tail performance, including fine-grained rehashing, transient locking, memory pre-allocation, and fingerprinting.","PeriodicalId":50222,"journal":{"name":"Journal of Computer Science and Technology","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138540030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Chinese Named Entity Recognition Augmented with Lexicon Memory 词汇记忆增强的中文命名实体识别

IF 1.9 3区计算机科学

Journal of Computer Science and Technology Pub Date : 2023-09-30 DOI: 10.1007/s11390-021-1153-y

Yi Zhou, Xiao-Qing Zheng, Xuan-Jing Huang

引用次数: 4

VTensor: Using Virtual Tensors to Build a Layout-Oblivious AI Programming Framework VTensor:使用虚拟张量构建无关布局的AI编程框架

IF 1.9 3区计算机科学

Journal of Computer Science and Technology Pub Date : 2023-09-30 DOI: 10.1007/s11390-022-1457-6

Feng Yu, Jia-Cheng Zhao, Hui-Min Cui, Xiao-Bing Feng, Jingling Xue

{"title":"VTensor: Using Virtual Tensors to Build a Layout-Oblivious AI Programming Framework","authors":"Feng Yu, Jia-Cheng Zhao, Hui-Min Cui, Xiao-Bing Feng, Jingling Xue","doi":"10.1007/s11390-022-1457-6","DOIUrl":"https://doi.org/10.1007/s11390-022-1457-6","url":null,"abstract":"Tensors are a popular programming interface for developing artificial intelligence (AI) algorithms. Layout refers to the order of placing tensor data in the memory and will affect performance by affecting data locality; therefore the deep neural network library has a convention on the layout. Since AI applications can use arbitrary layouts, and existing AI systems do not provide programming abstractions to shield the layout conventions of libraries, operator developers need to write a lot of layout-related code, which reduces the efficiency of integrating new libraries or developing new operators. Furthermore, the developer assigns the layout conversion operation to the internal operator to deal with the uncertainty of the input layout, thus losing the opportunity for layout optimization. Based on the idea of polymorphism, we propose a layout-agnostic virtual tensor programming interface, namely the VTensor framework, which enables developers to write new operators without caring about the underlying physical layout of tensors. In addition, the VTensor framework performs global layout inference at runtime to transparently resolve the required layout of virtual tensors, and runtime layout-oriented optimizations to globally minimize the number of layout transformation operations. Experimental results demonstrate that with VTensor, developers can avoid writing layout-dependent code. Compared with TensorFlow, for the 16 operations used in 12 popular networks, VTensor can reduce the lines of code (LOC) of writing a new operation by 47.82% on average, and improve the overall performance by 18.65% on average.","PeriodicalId":50222,"journal":{"name":"Journal of Computer Science and Technology","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138540032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cognition: Accurate and Consistent Linear Log Parsing Using Template Correction 认知:使用模板校正进行准确一致的线性日志解析

IF 1.9 3区计算机科学

Journal of Computer Science and Technology Pub Date : 2023-09-30 DOI: 10.1007/s11390-021-1691-3

Ran Tian, Zu-Long Diao, Hai-Yang Jiang, Gao-Gang Xie

{"title":"Cognition: Accurate and Consistent Linear Log Parsing Using Template Correction","authors":"Ran Tian, Zu-Long Diao, Hai-Yang Jiang, Gao-Gang Xie","doi":"10.1007/s11390-021-1691-3","DOIUrl":"https://doi.org/10.1007/s11390-021-1691-3","url":null,"abstract":"Logs contain runtime information for both systems and users. As many of them use natural language, a typical log-based analysis needs to parse logs into the structured format first. Existing parsing approaches often take two steps. The first step is to find similar words (tokens) or sentences. Second, parsers extract log templates by replacing different tokens with variable placeholders. However, we observe that most parsers concentrate on precisely grouping similar tokens or logs. But they do not have a well-designed template extraction process, which leads to inconsistent accuracy on particular datasets. The root cause is the ambiguous definition of variable placeholders and similar templates. The consequences include abuse of variable placeholders, incorrectly divided templates, and an excessive number of templates over time. In this paper, we propose our online log parsing approach Cognition. It redefines variable placeholders via a strict lower bound to avoid ambiguity first. Then, it applies our template correction technique to merge and absorb similar templates. It eliminates the interference of commonly used parameters and thus isolates template quantity. Evaluation through 16 public datasets shows that Cognition has better accuracy and consistency than the state-of-the-art approaches. It also saves up to 52.1% of time cost on average than the others.","PeriodicalId":50222,"journal":{"name":"Journal of Computer Science and Technology","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138540035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Model Checking for Probabilistic Multiagent Systems 概率多智能体系统的模型检验

IF 1.9 3区计算机科学

Journal of Computer Science and Technology Pub Date : 2023-09-30 DOI: 10.1007/s11390-022-1218-6

Chen Fu, Andrea Turrini, Xiaowei Huang, Lei Song, Yuan Feng, Li-Jun Zhang

{"title":"Model Checking for Probabilistic Multiagent Systems","authors":"Chen Fu, Andrea Turrini, Xiaowei Huang, Lei Song, Yuan Feng, Li-Jun Zhang","doi":"10.1007/s11390-022-1218-6","DOIUrl":"https://doi.org/10.1007/s11390-022-1218-6","url":null,"abstract":"In multiagent systems, agents usually do not have complete information of the whole system, which makes the analysis of such systems hard. The incompleteness of information is normally modelled by means of accessibility relations, and the schedulers consistent with such relations are called uniform. In this paper, we consider probabilistic multiagent systems with accessibility relations and focus on the model checking problem with respect to the probabilistic epistemic temporal logic, which can specify both temporal and epistemic properties. However, the problem is undecidable in general. We show that it becomes decidable when restricted to memoryless uniform schedulers. Then, we present two algorithms for this case: one reduces the model checking problem into a mixed integer non-linear programming (MINLP) problem, which can then be solved by Satisfiability Modulo Theories (SMT) solvers, and the other is an approximate algorithm based on the upper confidence bounds applied to trees (UCT) algorithm, which can return a result whenever queried. These algorithms have been implemented in an existing model checker and then validated on experiments. The experimental results show the efficiency and extendability of these algorithms, and the algorithm based on UCT outperforms the one based on MINLP in most cases.","PeriodicalId":50222,"journal":{"name":"Journal of Computer Science and Technology","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138540026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Top-down Text-Level Discourse Rhetorical Structure Parsing with Bidirectional Representation Learning 基于双向表征学习的自顶向下语篇修辞结构分析

IF 1.9 3区计算机科学

Journal of Computer Science and Technology Pub Date : 2023-09-30 DOI: 10.1007/s11390-022-1167-0

Long-Yin Zhang, Xin Tan, Fang Kong, Pei-Feng Li, Guo-Dong Zhou

{"title":"Top-down Text-Level Discourse Rhetorical Structure Parsing with Bidirectional Representation Learning","authors":"Long-Yin Zhang, Xin Tan, Fang Kong, Pei-Feng Li, Guo-Dong Zhou","doi":"10.1007/s11390-022-1167-0","DOIUrl":"https://doi.org/10.1007/s11390-022-1167-0","url":null,"abstract":"Early studies on discourse rhetorical structure parsing mainly adopt bottom-up approaches, limiting the parsing process to local information. Although current top-down parsers can better capture global information and have achieved particular success, the importance of local and global information at various levels of discourse parsing is different. This paper argues that combining local and global information for discourse parsing is more sensible. To prove this, we introduce a top-down discourse parser with bidirectional representation learning capabilities. Existing corpora on Rhetorical Structure Theory (RST) are known to be much limited in size, which makes discourse parsing very challenging. To alleviate this problem, we leverage some boundary features and a data augmentation strategy to tap the potential of our parser. We use two methods for evaluation, and the experiments on the RST-DT corpus show that our parser can primarily improve the performance due to the effective combination of local and global information. The boundary features and the data augmentation strategy also play a role. Based on gold standard elementary discourse units (EDUs), our parser significantly advances the baseline systems in nuclearity detection, with the results on the other three indicators (span, relation, and full) being competitive. Based on automatically segmented EDUs, our parser still outperforms previous state-of-the-art work.","PeriodicalId":50222,"journal":{"name":"Journal of Computer Science and Technology","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138540017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Path-Based Multicast Routing for Network-on-Chip of the Neuromorphic Processor 基于路径的神经形态处理器片上网络组播路由

IF 1.9 3区计算机科学

Journal of Computer Science and Technology Pub Date : 2023-09-30 DOI: 10.1007/s11390-022-1232-8

Zi-Yang Kang, Shi-Ming Li, Shi-Ying Wang, Lian-Hua Qu, Rui Gong, Wei Shi, Wei-Xia Xu, Lei Wang

{"title":"Path-Based Multicast Routing for Network-on-Chip of the Neuromorphic Processor","authors":"Zi-Yang Kang, Shi-Ming Li, Shi-Ying Wang, Lian-Hua Qu, Rui Gong, Wei Shi, Wei-Xia Xu, Lei Wang","doi":"10.1007/s11390-022-1232-8","DOIUrl":"https://doi.org/10.1007/s11390-022-1232-8","url":null,"abstract":"Network-on-Chip (NoC) is widely adopted in neuromorphic processors to support communication between neurons in spiking neural networks (SNNs). However, SNNs generate enormous spiking packets due to the one-to-many traffic pattern. The spiking packets may cause communication pressure on NoC. We propose a path-based multicast routing method to alleviate the pressure. Firstly, all destination nodes of each source node on NoC are divided into several clusters. Secondly, multicast paths in the clusters are created based on the Hamiltonian path algorithm. The proposed routing can reduce the length of path and balance the communication load of each router. Lastly, we design a lightweight microarchitecture of NoC, which involves a customized multicast packet and a routing function. We use six datasets to verify the proposed multicast routing. Compared with unicast routing, the running time of path-based multicast routing achieves 5.1x speedup, and the number of hops and the maximum transmission latency of path-based multicast routing are reduced by 68.9% and 77.4%, respectively. The maximum length of path is reduced by 68.3% and 67.2% compared with the dual-path (DP) and multi-path (MP) multicast routing, respectively. Therefore, the proposed multicast routing has improved performance in terms of average latency and throughput compared with the DP or MP multicast routing.","PeriodicalId":50222,"journal":{"name":"Journal of Computer Science and Technology","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138540074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Parallel Bounded Search for the Maximum Clique Problem 最大团问题的并行有界搜索

IF 1.9 3区计算机科学

Journal of Computer Science and Technology Pub Date : 2023-09-30 DOI: 10.1007/s11390-022-1803-8

Hua Jiang, Ke Bai, Hai-Jiao Liu, Chu-Min Li, Felip Manyà, Zhang-Hua Fu

引用次数: 0

FedIERF: Federated Incremental Extremely Random Forest for Wearable Health Monitoring FedIERF:可穿戴健康监测的联邦增量极度随机森林

IF 1.9 3区计算机科学

Journal of Computer Science and Technology Pub Date : 2023-09-30 DOI: 10.1007/s11390-023-3009-0

Chun-Yu Hu, Li-Sha Hu, Lin Yuan, Dian-Jie Lu, Lei Lyu, Yi-Qiang Chen

{"title":"FedIERF: Federated Incremental Extremely Random Forest for Wearable Health Monitoring","authors":"Chun-Yu Hu, Li-Sha Hu, Lin Yuan, Dian-Jie Lu, Lei Lyu, Yi-Qiang Chen","doi":"10.1007/s11390-023-3009-0","DOIUrl":"https://doi.org/10.1007/s11390-023-3009-0","url":null,"abstract":"Wearable health monitoring is a crucial technical tool that offers early warning for chronic diseases due to its superior portability and low power consumption. However, most wearable health data is distributed across different organizations, such as hospitals, research institutes, and companies, and can only be accessed by the owners of the data in compliance with data privacy regulations. The first challenge addressed in this paper is communicating in a privacy-preserving manner among different organizations. The second technical challenge is handling the dynamic expansion of the federation without model retraining. To address the first challenge, we propose a horizontal federated learning method called Federated Extremely Random Forest (FedERF). Its contribution-based splitting score computing mechanism significantly mitigates the impact of privacy protection constraints on model performance. Based on FedERF, we present a federated incremental learning method called Federated Incremental Extremely Random Forest (FedIERF) to address the second technical challenge. FedIERF introduces a hardness-driven weighting mechanism and an importance-based updating scheme to update the existing federated model incrementally. The experiments show that FedERF achieves comparable performance with non-federated methods, and FedIERF effectively addresses the dynamic expansion of the federation. This opens up opportunities for cooperation between different organizations in wearable health monitoring.","PeriodicalId":50222,"journal":{"name":"Journal of Computer Science and Technology","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138540008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Side-Channel Analysis for the Re-Keying Protocol of Bluetooth Low Energy 低功耗蓝牙重键协议的边信道分析

IF 1.9 3区计算机科学

Journal of Computer Science and Technology Pub Date : 2023-09-30 DOI: 10.1007/s11390-022-1229-3

Pei Cao, Chi Zhang, Xiang-Jun Lu, Hai-Ning Lu, Da-Wu Gu

{"title":"Side-Channel Analysis for the Re-Keying Protocol of Bluetooth Low Energy","authors":"Pei Cao, Chi Zhang, Xiang-Jun Lu, Hai-Ning Lu, Da-Wu Gu","doi":"10.1007/s11390-022-1229-3","DOIUrl":"https://doi.org/10.1007/s11390-022-1229-3","url":null,"abstract":"In the era of the Internet of Things, Bluetooth low energy (BLE/BTLE) plays an important role as a well-known wireless communication technology. While the security and privacy of BLE have been analyzed and fixed several times, the threat of side-channel attacks to BLE devices is still not well understood. In this work, we highlight a side-channel threat to the re-keying protocol of BLE. This protocol uses a fixed long term key for generating session keys, and the leakage of the long term key could render the encryption of all the following (and previous) connections useless. Our attack exploits the side-channel leakage of the re-keying protocol when it is implemented on embedded devices. In particular, we present successful correlation electromagnetic analysis and deep learning based profiled analysis that recover long term keys of BLE devices. We evaluate our attack on an ARM Cortex-M4 processor (Nordic Semiconductor nRF52840) running Nimble, a popular open-source BLE stack. Our results demonstrate that the long term key can be recovered within only a small amount of electromagnetic traces. Further, we summarize the features and limitations of our attack, and suggest a range of countermeasures to prevent it.","PeriodicalId":50222,"journal":{"name":"Journal of Computer Science and Technology","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138540018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0