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81.
The Malaysian electricity industry evolved from a vertically integrated utility into a single-buyer model, which considered a precursor to deregulation and a competitive market. This study considers electricity sector reform in Malaysia and proposes a market structure for the industry. We focus on the single-buyer model and the pool model for the analysis with the recommendation on reform stages required to ensure a smooth and successful market transition. A smooth transition from regulated market into deregulated market will ensure market stability and sustainability of the energy market. It will also provide enough time for the market participants to adapt and transit from regulated to deregulated energy market. 相似文献
82.
Side-channel attacks have recently progressed into software-induced attacks. In particular, a rowhammer attack, which exploits the characteristics of dynamic random access memory (DRAM), can quickly and continuously access the cells as the cell density of DRAM increases, thereby generating a disturbance error affecting the neighboring cells, resulting in bit flips. Although a rowhammer attack is a highly sophisticated attack in which disturbance errors are deliberately generated into data bits, it has been reported that it can be exploited on various platforms such as mobile devices, web browsers, and virtual machines. Furthermore, there have been studies on bypassing the defense measures of DRAM manufacturers and the like to respond to rowhammer attacks. A rowhammer attack can control user access and compromise the integrity of sensitive data with attacks such as a privilege escalation and an alteration of the encryption keys. In an attempt to mitigate a rowhammer attack, various hardware- and software-based mitigation techniques are being studied, but there are limitations in that the research methods do not detect the rowhammer attack in advance, causing overhead or degradation of the system performance. Therefore, in this study, a rowhammer attack detection technique is proposed by extracting common features of rowhammer attack files through a static analysis of rowhammer attack codes. 相似文献
83.
As blockchain technology is gaining popularity in industry and society, solutions for Verification and Validation (V&V) of blockchain-based software applications (BC-Apps) have started gaining equal attention. To ensure that BC-Apps are properly developed before deployment, it is paramount to apply systematic V&V to verify their functional and non-functional requirements. While existing research aims at addressing the challenges of engineering BC-Apps by providing testing techniques and tools, blockchain-based software development is still an emerging research discipline, and therefore, best practices and tools for the V&V of BC-Apps are not yet sufficiently developed. In this paper, we provide a comprehensive survey on V&V solutions for BC-Apps. Specifically, using a layered approach, we synthesize V&V tools and techniques addressing different components at various layers of the BC-App stack, as well as across the whole stack. Next, we provide a discussion on the challenges associated with BC-App V&V, and summarize a set of future research directions based on the challenges and gaps identified in existing research work. Our study aims to highlight the importance of BC-App V&V and pave the way for a disciplined, testable, and verifiable BC development. 相似文献
84.
Aiming at the performance degradation of the existing presentation attack detection methods due to the illumination variation, a two-stream vision transformers framework (TSViT) based on transfer learning in two complementary spaces is proposed in this paper. The face images of RGB color space and multi-scale retinex with color restoration (MSRCR) space are fed to TSViT to learn the distinguishing features of presentation attack detection. To effectively fuse features from two sources (RGB color space images and MSRCR images), a feature fusion method based on self-attention is built, which can effectively capture the complementarity of two features. Experiments and analysis on Oulu-NPU, CASIA-MFSD, and Replay-Attack databases show that it outperforms most existing methods in intra-database testing and achieves good generalization performance in cross-database testing. 相似文献
85.
《International Journal of Hydrogen Energy》2022,47(45):19837-19849
Microbial fuel cell (MFC) has become a very important biotechnological tool to produce clean energy in recent years. It is very important to adjust the output voltage and power density in order to obtain the desired energy quickly and smoothly at the output of the MFC. In this study, an optimization-based neuro-fuzzy inference controller is proposed for improving voltage tracking performance of the MFC. A double-chambers MFC model including biochemical reactions, Butler-Volmer expressions and mass/charge balances was studied and Particle Swarm Optimization (PSO) and Improved Grey Wolf Optimization (IGWO) algorithms are used to adjust the parameters of the neuro-fuzzy controller. The results show that PSO and IGWO based controllers have efficient performances to follow the reference voltage pattern quickly and robustly against external load changes, distributions and parameter uncertainties. Moreover, it was observed that IGWO was a more stable and robust controller than PSO according to rise time, overshoot and peak time. 相似文献
86.
《International Journal of Hydrogen Energy》2022,47(39):17285-17312
Hydrogen energy storage systems (HydESS) and their integration with renewable energy sources into the grid have the greatest potential for energy production and storage while controlling grid demand to enhance energy sustainability. This paper presents a bibliometric analysis based on a comprehensive review of the highly cited articles on HydESS to provide a detailed insight into future directions and applications. The study was carried out by using the Scopus database search engine to look for filtered keywords in the HydESS and related research. It can be demonstrated that the HydESS literature expanded rapidly from 2016 to 2021 compared to 2011 to 2015. It is found that 89.17% of published articles explained control and test systems-based methods, whereas 10.83% of publications discuss review assessments. Our analysis of highly cited articles on HydESS highlights several aspects, such as methods and systems, issues, difficulties, and challenges to establishing current constraints and research gaps. This evaluation can enhance operational performance, environmental friendliness, energy savings, uninterrupted power supply service, cost benefits, on-site generation, and adaptability. It would be beneficial for technology development and the growth of the hydESS industry. This study may act as a guideline not only for academics in determining the line of research and generating additional discoveries, but also for the government in formulating financial strategies. 相似文献
87.
宋朝兴起的地方官窑为宫廷烧造御用瓷是官手工业发展的亮点之一,并逐步形成了两宋地方官窑执行的御用瓷设计制度,设计制度形成绝非偶然,它是宋朝强化皇权意志、器用制度与地方精湛制瓷工艺共同作用的结果。地方官窑主要执行有奉御董造制度、禁廷制样制度。体现的御用瓷设计制度特征十分明显:前期是指专门接受宫廷敕命,由专官管理,奉御烧造宫廷各种用瓷,有命则供,否则止;后期是指宫廷对御用瓷有专门的设计图式,特由礼部礼制局彩画制样后,向地方官窑降发图样烧造御用瓷。尤其是地方官窑执行的禁廷制样须索制度为明代御器厂和清代御窑厂所继承。 相似文献
88.
《International Journal of Hydrogen Energy》2022,47(53):22545-22558
This work shows the results of the experimental assessment of the HI-SEA joint laboratory between Fincantieri, the main Italian shipbuilder, and the University of Genova. The HI-SEA system is a 240 kW real-scale test rig complete of auxiliaries, made up of 8 Proton Exchange Membrane Fuel Cell stacks installed on two parallel branches, which can operate independently or in parallel by means of two dedicated DC/DC converters. The experimental assessment is performed by considering: (i) Stationary performance; (ii) dynamic performance; (iii) a maritime operative profile defined together with Fincantieri. The experimental results obtained in this work demonstrated that the system can successfully respond to static, dynamic, and typical maritime operative load profiles. It was also assessed the ability of the system to work simultaneously with two parallel branches, by means of two DC/DC converters, which represents a clear advantage in terms of load sharing and redundance onboard for security issues. Furthermore, the present study gives important advice and criteria for the design, construction, and control of similar Fuel Cell complete systems for maritime applications, which is particularly relevant considering that experimental studies on complete Fuel Cell systems is still limited. 相似文献
89.
本文以历年《中国体育事业统计年鉴》中的积累数据为研究对象,通过对各类统计数据表的分析,运用数据库技术和软件工程方法,确定表的结构,建立年鉴数据库;研究运用c#语言设计开发基于网络的c/s模式前端客户端,对数据库进行添加、删除、修改、查询、导出等相关操作,实现对《中国体育事业统计年鉴》数据的网络化管理。 相似文献
90.
针对综合监控系统中人机界面用户权限和报警管理的差异化需求,设计并完成了基于用户权限的报警管理功能,实现了用户权限与报警信息的集中管理,并取得了良好的应用效果。 相似文献