分类: 能源科学 >> 能源(综合) 提交时间: 2024-03-28
摘要: Considering the huge consumption of traditional energy and the rising demand for electricity, the development of renewable energy is very necessary. In this paper, an energy system integrating biomass energy, solar and two-stage organic Rankine cycle (ORC) is proposed, which uses the stable energy output of biomass energy to compensate for the volatility of solar modules. The proposed system comprises a biomass boiler, photovoltaic thermal panels (PV/T), evaporators, condensers, working medium pumps, turbines, a preheater and an air preheater. In addition, conventional and advanced exergy, exergoeconomic and exergoenvironmental (3E) analyses are carried out. Conventional 3E analyses reveal two components that require priority improvement. They are respectively evaporator 1 with the largest exergy destruction (708.2kW) and exergy destruction environmental impact rate (775.3 mPt/h) and evaporator 2 with the largest exergy destruction cost rate (19.15$/h). The results of advanced 3E analyses show that the largest avoidable endogenous exergy destruction is condenser 1 (136.6kW), the largest avoidable endogenous exergy destruction cost rate is condenser 2 (3.377$/h), and the largest avoidable endogenous exergy destruction environmental impact rate is condenser 1 (196.1mPt/h). These mean that these components have great potential for improvement in reducing exergy destruction, saving cost and protecting the environment. In addition, the avoidable endogenous exergy destruction/cost/environmental impact rate of evaporator 2 are negative, so evaporator 2 is not suitable as a priority component for improvement, which is contrary to the conclusions of conventional 3E analyses. It is found that conventional 3E analyses can only point out the biggest exergy destruction point, but cannot indicate whether the components with the greatest exergy destruction have the greatest potential for improvement. However, advanced 3E analyses can show the improvement potential of each component by improving its own performance and the external conditions. Therefore, it is necessary to conduct advanced 3E analyses.
分类: 工程与技术科学 >> 计量学 分类: 工程与技术科学 >> 仪器仪表技术 提交时间: 2024-03-28
摘要: mainlyintroducesthedevelopmentandapplicationofharmonicpowermeteringtechnologyinChina sincethe 21stcentury.Withtheincreasingdemandfor harmonic powermeteringinthe powergrid,theintroductionofthe world’sfirstharmonicpowerdefinitionstandard,IEEE1459---2000,haspromotedthedevelopmentof harmonicpowermeteringtechnology.Thetextalsomentionstheelementsoftheapplicationanddevelopmentofharmonicenergymetering technology, includingtheexpansionofthescopeofharmonicpollutioninthepowergrid,theconfusionofharmonicenergy metering instrumentadopted by different users, and thenewtypeofharmonicenergymeteringtechnologyintroducedinthe world.Inaddition,thispaperalsointroducesthedomesticindependentdevelopmentofharmonicenergymeasurementtechnology, such as 0.2S level three-phase electricity meter,0.2S three-phase harmonic active energy metering seriesproducts,threephasewaveactiveenergymeteringproducts,andusingtheHilbertdigitalfilterandlowfrequencyfiltercalculationharmonicreactivepowermeteringchipdevelopmentofcutting-edgepracticaltechnology.Ingeneral,thispaper summarizesthedevelopment process,applicationstatusandfuturedevelopmentdirectionofharmonic power measurementtechnology in China, as well as the related technology and productachievements.
提交时间: 2024-03-28
摘要: Smart meter is not only a device used to measure the amount of electricity, but also a core component of the smart grid, realizing the efficient monitoring, prediction and management of power use. With an insight into the evolution of smart meter technology, I realized that this change didn't happen overnight. It has undergone a long journey from the initial mechanical electricity meters to the electronic electricity meters, and now to the highly intelligent electricity meters. Technological breakthroughs at each stage have laid the foundation for the final form of smart meters. In the era of mechanical watt-hour meters, the measurement of electric energy mainly depends on the rotation and counting of mechanical structures. The accuracy and stability of this method are affected by mechanical wear, environmental interference and other factors, and it is difficult to meet the increasing demand for power management. With the rapid development of electronic technology, the electronic electricity meter came into being. It uses electronic technology to sample and process the current and voltage, which greatly improves the accuracy and stability of the measurement. At the same time, the electronic electricity meter also has the function of remote meter reading and data processing, which has brought great convenience to the power management. However, there still have some limitations, such as the complexity of data processing and the limitation of communication capacity. It is these challenges that drive the creation of smart power meters. smart meters combine advanced technologies such as the Internet of Things, big data and cloud computing to realize the real-time monitoring, analysis and prediction of the use of power.
分类: 交通运输工程 >> 水路运输 提交时间: 2024-03-28
摘要: Vessel recognition plays important role in ensuring navigation safety. However, existing methods are mainly based on a single sensor, such as automatic identification system (AIS), marine radar, closed-circuit television (CCTV), etc. To this end, this paper proposes a coarse-to-fine recognition method by fusing CCTV and marine radar, called multi-scale matching vessel recognition (MSM-VR). This method first proposes a novel calibration method that does not use any additional calibration target. The calibration is transformed to solve an N point registration model. Furthermore, marine radar image is used for coarse detection. A region of interest (ROI) area is computed for coarse detection results. Lastly, we design a novel convolutional neural network (CNN) called VesNet and transform the recognition into feature extraction. The VesNet is used to extract the vessel features. As a result, the MVM-VR method has been validated by using actual datasets collected along different waterways such as Nanjing waterway and Wuhan waterway, China, covering different times and weather conditions. Experimental results show that the MSM-VR method can adapt to different times, different weather conditions, and different waterways with good detection stability. The recognition accuracy is no less than 96%. Compared to other methods, the proposed method has high accuracy and great robustness.
分类: 能源科学 >> 能源(综合) 提交时间: 2024-03-28
摘要: With rapidly increasing consumption of energy, shipping industry has imposed a huge burden on the marine environment. It is a general trend to increase the use of renewable energy on ships to improve the ship sustainability. This article summarized the current development and application of solar energy, wind energy and fuel cell in ship power systems. Furthermore, in order to investigate the advantages of sustainable design for the ships, for the first time, a hybrid PV, wind and fuel cell energy system was established for an oil tanker, and the economic and environmental analyses of the hybrid system were performed. The analysis results demonstrate that the optimal hybrid energy system can reduce 151,467kg emission of CO2 and provide 2.92% electricity for the ship gird per year.
分类: 工程与技术科学 >> 工程通用技术 提交时间: 2024-03-28
摘要: As a new intelligentoptimization algorithm, the African vulturesoptimization algorithm(AVOA) has been widely used in various fields today. However, when solving complex multimodal problems, the AVOA still has some shortcomings, such as low searching accuracy, deficiency on the search capability and tendency to fall into local optimum. In order to alleviate the main shortcomings of the AVOA, a nonlinear African vulture optimization algorithm combining Henon chaotic mapping theory and reverse learning competition strategy (HWEAVOA) is proposed. Firstly, the Henon chaotic mapping theory and elite population strategy are proposed to improve the randomness and diversity of the vulture’s initial population; Furthermore, the nonlinear adaptive incremental inertial weight factor is introduced in the location update phase to rationally balance the exploration and exploitation abilities, and avoid individual falling into a local optimum; The reverse learning competition strategy is designed to expand the discovery fields for the optimal solution and strengthen the ability to jump out of thelocal optimal solution. HWEAVOA and other advanced comparison algorithms are used to solve classical and CEC2022 test functions. Compared with other algorithms, the convergence curves of the HWEAVOA drop faster and the line bodies are smoother. These experimental results show the proposed HWEAVOA is ranked first in all test functions, which is superior to the comparison algorithms in convergence speed, optimization ability, and solution stability. Meanwhile, HWEAVOA has reached the general level in thealgorithm complexity, and its overall performance is competitive in theswarm intelligence algorithms.
分类: 工程与技术科学 >> 计量学 分类: 工程与技术科学 >> 仪器仪表技术 提交时间: 2024-03-28
摘要: 智能电表通信技术研究是电力领域中一个重要的研究方向,涉及对智能电表通信系统的深入探索与技术创新。随着智能电网的发展,智能电表作为电网与用户之间的关键信息交互节点,其通信技术的研究与应用对于提升电网的智能化水平、优化电力资源配置具有重要意义。研究内容包括对现有的通信技术进行评估与改进,以适应智能电表通信的特殊需求。例如,窄带与宽带电力线载波通信作为电表行业可以主导研究与应用的技术方向,其免维护技术、自动调试终端、自动组网仪等方面的进展都是当前研究的热点。同时,对于远程无线通信系统的研究与优化,以及智能终端的研发,也是智能电表通信技术研究的重要方面。此外,智能电表通信技术的研究还需要关注通信协议、通信安全、数据处理等方面的问题。通过制定统一的通信协议,可以实现不同设备之间的互联互通,提高系统的兼容性和可扩展性。同时,加强通信安全的研究,可以保障电力数据的安全传输,防止数据泄露和非法访问。在数据处理方面,通过采用先进的数据分析技术,可以对电力数据进行深入挖掘,为电力行业的决策和运营提供有力支持。总的来说,智能电表通信技术研究是一个涉及多个领域的综合性研究课题,需要不断跟踪新技术的发展,结合实际需求进行技术创新和应用推广,以推动电力行业的智能化发展。
分类: 工程与技术科学 >> 计量学 分类: 工程与技术科学 >> 仪器仪表技术 提交时间: 2024-03-28
摘要: 能源计量与能效管理在企业运营中占据重要地位。能源计量是指对能源流程中的各个环节进行数量、质量、性能参数及相关特征参数的检测、度量和计算。它不仅是企业加强能源管理、提高能源管理水平的基础,还是企业贯彻执行国家节能法规、政策、标准,合理用能,优化能源结构,提高能源利用效率,提高经济效益和市场竞争力的重要保证。能源计量工作通常分为三级计量,即进出用能单位、次级用能单位(如车间、工艺段等)以及主要用能设备。这种分级管理有助于企业更精确地掌握能源使用情况,从而更有效地进行能源管理和节能降耗。能效管理则是基于能源计量的数据,通过科学的管理手段和技术措施,实现能源的有效利用和节约。它涉及能源的采购、存储、转换、使用等各个环节,目标是提高能源的使用效率,降低能源消耗,减少对环境的影响。然而,在实际操作中,一些企业可能由于能源计量意识不强,对能源计量工作重视不足,导致能源使用浪费。此外,部分企业可能缺乏专业的能源计量人员,对能源计量数据的处理和分析能力不足,也影响了能效管理的效果。因此,企业需要提高能源计量意识,加强能源计量管理,培养专业的能源计量人员,并充分利用能源计量数据进行能效管理。同时,政府和社会也应加强对能源计量和能效管理工作的宣传和推广,提高全社会的节能意识和能力。至于能源计量与能效管理在特定企业或行业中的具体应用和实践,以及这些能源在使用过程中如何进行计量和管理,将需要根据具体企业的生产流程、设备状况、能源使用特点等因素进行具体分析。总的来说,能源计量与能效管理是企业实现可持续发展和节能减排目标的重要手段。
分类: 工程与技术科学 >> 计量学 分类: 工程与技术科学 >> 仪器仪表技术 提交时间: 2024-03-28
摘要: 深入探讨了高端电能表的研究现状与发展趋势,重点分析了进口高端电表的差异化设计、技术标准及特殊测试方法。同时,结合双向互动智能电表新需求,提出了关键技术设计方案,为电表行业提供了有价值的参考。
分类: 工程与技术科学 >> 计量学 分类: 工程与技术科学 >> 仪器仪表技术 提交时间: 2024-03-28
摘要: 提出一套全面而系统的多功能电能表性能评估品质试验方法。通过对比研究国内外相关标准和先进电表的技术指标,本方法综合考虑了电表的准确性、稳定性、可靠性以及智能化程度等多个方面,为电能表行业的品质提升和技术创新提供了有力支持。
分类: 核科学技术 >> 核科学与技术 提交时间: 2024-03-28
摘要: Due to their excellent safety performance, dispersion fuels are widely used in advanced reactors, such as high-temperature gas-cooled reactors (HTGRs). Compared with deterministic methods, the Monte Carlo method has more advantages in the geometric modeling of stochastic media. The explicit modeling method has high computational accuracy and high computational cost. The chord length sampling (CLS) method can improve computational efficiency by sampling the chord length during neutron transport using the matrix chord length’s probability density function (PDF). This study shows that the excluded-volume effect in realistic stochastic media can introduce significant deviations into the CLS. A chord length correction approach is proposed to obtain the chord length correction factor by developing the Particle code based on equivalent transmission probability. Through numerical analysis against reference solutions from explicit modeling in the RMC code, it was demonstrated that CLS with the proposed correction method provides good accuracy for addressing the excluded-volume effect in realistic infinite stochastic media.
分类: 其他 >> 综合 提交时间: 2024-03-28 合作期刊: 《文献与数据学报》
摘要: [目的 / 意义]指出《大规模现代汉语分词语料库构建及应用》一书的主要价值与贡献,旨在为中文语料库的构建提供借鉴,以促进大语言模型下中文自然语言处理的快速发展。[方法 / 过程]从宏观和微观的视角,对新时代人民日报分词语料库的构建和语料库相关研究综述进行了基于语料库计量语言学的分析,并对深度学习下的人民日报知识组织等内容进行了评介。[结果 / 结论]《大规模现代汉语分词语料库构建及应用》一书基于新时代人民日报分词语料库构建及应用进行研究,不仅传承了北京大学人民日报语料库的体系和理念,而且在一定程度上为解决领域化自然语言处理的任务提供了相应的方案。
分类: 图书馆学、情报学 >> 各类型图书馆 提交时间: 2024-03-28 合作期刊: 《文献与数据学报》
摘要: [目的 / 意义]依托公共图书馆的文化资源优势,探索中国特色的少儿阅读服务品牌建设,助推“双减”政策有效实施。[方法 / 过程]采用文献研究法、比较研究法等,梳理从 WOS 数据库和CNKI 数据库中搜索到的相关文献资源,并结合实践案例,分析国内外少儿阅读服务品牌建设现状,探索公共图书馆建设少儿阅读服务品牌的优化路径。[结果 / 结论]通过借鉴国内外公共图书馆少儿阅读服务品牌的成功经验, 从政策法规、阅读空间、服务效能、阅读群体、阅读模式、职业培训、社会参与七个层面提出了建设少儿阅读服务品牌优化策略。
分类: 图书馆学、情报学 >> 各类型图书馆 提交时间: 2024-03-28 合作期刊: 《文献与数据学报》
摘要: [目的 / 意义]数字化时代,数字素养成为公民的必备素质。调查老年人的数字素养水平,明晰老年人数字素养差异尤为必要。本文通过以点带面的调查分析,了解老年人数字素养状况,提出有针对性的数字素养提升策略。[方法 / 过程]以江苏省南通市为调研地区,从数字意识素养、数字技能素养、数字安全素养、数字道德素养四个维度调查老年人的数字素养水平,并对老年群体数字素养水平存在的差异进行分析。[结果 / 结论]研究发现,南通市老年人的数字素养水平整体偏低,老年人数字素养水平因年龄、学历、身体健康状况、居住地、居住方式、子女是否支持使用智能设备、是否有稳定经济来源等不同而产生显著差异。本文基于上述结论提出帮助老年人树立“数字信心”、推动智能产品的适老化改造、倡导家庭中年轻一辈对于老年人的“数字反哺”、鼓励社区开展老年人智能设备帮扶培训、降低互联网使用成本等措施,为有效提升我国老年群体数字素养提供借鉴。
分类: 管理学 >> 管理学其他学科 分类: 其他 >> 综合 分类: 医学、药学 >> 医学、药学其他学科 提交时间: 2024-03-28 合作期刊: 《文献与数据学报》
摘要: [目的 / 意义]在线健康社区是人们获取健康信息的重要途径,研究在线健康社区用户用药咨询需求,有助于在线健康社区药品服务优化及可持续发展。[方法 / 过程]以 39 健康网为例,首先,利用 Python 编码爬取肠胃用药类药品的 59 048 条用药咨询评论,并进行预处理;其次,使用 TF-IDF、TextRank、LDA 主题模型等文本挖掘方法对实验数据进行主题关键词挖掘,并进行关键词共现网络分析;最后,综合分析在线健康社区用户用药咨询需求的主题特征,并提出优化建议。[结果 / 结论]研究结果发现在线健康社区用户主要关注药品治疗效果、服用方式、不良反应、药品区别以及孕妇等特殊人群在用药时的注意事项等。本研究一方面为药品厂商调整优化药品说明书内容提供了理论依据,另一方面为在线健康社区优化药品说明书内容布局以及建立或完善药品科普服务指引了方向。
分类: 其他 >> 综合 提交时间: 2024-03-28 合作期刊: 《文献与数据学报》
摘要: [目的 / 意义]推动政府数据共享开放是促进数字经济发展、增强社会治理效能的基本要义。[方法 / 过程]基于需求导向、动力支撑与数字赋能三维框架,以中国 31 个省份(未含香港、澳门、台湾地区)为研究案例,运用模糊集定性比较分析方法(fsQCA)对政府数据开放的影响因素进行组态分析。[结果 / 结论]单一因素并不能够驱动高政府数据开放水平的产生,而是以组态形式发挥作用;需求导向、动力支撑与数字赋能维度各要素交互作用形成驱动政府数据开放的 5 种组态路径;根据主导力量的不同,可将组态路径概括为三种类型,即需求导向型、数字赋能型和混合联动型。为此,要识别驱动地方政府数据开放的关键力量,因地制宜制定最优政策工具集,推进政府数据有序开放,进一步释放数据活力和效益。
分类: 图书馆学、情报学 >> 藏书建设和藏书组织 提交时间: 2024-03-28 合作期刊: 《文献与数据学报》
摘要: [目的 / 意义]粤港澳大湾区建设是新时代国家发展战略的重要组成部分,粤剧是连接大湾区人民情感和共同记忆的重要文化载体。粤港澳大湾区粤剧文献资源共建共享既是适应时代发展的内在要求,也是推进大湾区文化发展的重要举措。[方法 / 过程]本研究以粤港澳大湾区 11 个市 36个文化和科研机构作为调研对象,通过文献调研、网络调研和工作会等方式对粤港澳大湾区粤剧文献资源的分布状况、区域特点进行调研。[结果 / 结论]当前粤港澳大湾区粤剧文献资源具有资源富集、类型齐全、文献价值颇高、分布不均、亟待保护、利用不足等特点,文章从建立共享机制、搭建共享平台、加强机构协同、建设联合品牌等角度,提出了粤港澳大湾区粤剧文献资源共建共享的实践路径。
分类: 图书馆学、情报学 >> 情报资料的处理 提交时间: 2024-03-28 合作期刊: 《文献与数据学报》
摘要: [目的 / 意义]智慧图书馆研究不仅要聚焦当下、探索未来,亦需回顾过往、追根溯源。本文通过对国际智慧图书馆领域历史根源文献进行识别与分析,为研究者梳理领域发展脉络、发现重要节点文献提供参考。[方法 / 过程]以 Web of Science 核心数据集中的智慧图书馆领域 617 篇施引文献、14 949篇参考文献为数据源,基于 CRExplorer 软件引文出版年光谱功能,构建了历史根源文献识别与分析框架。依据参考文献年度被引量、5 年平均中值偏差曲线变化趋势,将该领域研究阶段划分为铺垫期、萌芽期、初始发展期以及快速发展期,在此基础上,识别出历史根源文献 17 篇。[结果 / 结论]通过文献分析发现,智慧图书馆领域研究呈现历史根源文献存在显著跨学科性、研究内容从技术至理论与用户体验转变、典型研究主题连续性较弱且出现时间间隔较大、作者多以“大家”为主且新生力量近年崭露头角等特征。
分类: 其他 >> 综合 提交时间: 2024-03-28 合作期刊: 《文献与数据学报》
摘要: [目的 / 意义]标准数字化能够深度挖掘标准潜在知识,并释放标准潜在价值。标准数字化治理战略直接关乎我国数字经济发展和国际竞争力的提升。[方法 / 过程]基于全球标准数字化变革趋势,从新技术、发展政策、发展格局、治理理念四方面进行研究。[结果 / 结论]研究结果表明:(1)标准数字化治理需把握四个机遇,一是标准数字化新技术促进标准链产业链全链条发展,二是标准化发展政策鼓励引导标准数字化发展,三是传统标准化发展格局产生变革,四是标准数据治理理念发生改变。(2)标准数字化治理正面临三个挑战,一是基本理论、关键技术、实施路径和应用场景尚未形成完整体系,二是成熟产品和优秀试点案例较少,三是制度体系和管理机制有待健全和完善。(3)标准数字化治理需考虑四项对策,一是大力发展基础概念体系和基础共性关键技术,二是强化相关政策保障,三是推动相关理论与各类业务场景融合和创新应用,四是提前谋划未来国际市场。
分类: 其他 >> 综合 提交时间: 2024-03-28 合作期刊: 《文献与数据学报》
摘要: [目的 / 意义]皮书评价在皮书发展过程中发挥着关键的引领作用,是皮书分级资助、评奖及淘汰的重要衡量依据。科学合理的皮书影响力评价指标体系能够为皮书评价工作的有序进行提供保障,对于保证评价结果公正客观、推动皮书评价发挥学术引领作用具有重要意义。[方法 / 过程]采用文献调查法、问卷调查法及层次分析法,综合考虑各项原则,设置决策影响力、学术影响力、使用影响力和社会影响力 4 个一级指标,下设 10 个二级指标和 16 个三级指标,确定指标权重,选择 51 本第十二届“优秀皮书奖”皮书进行实证研究。[结果 / 结论] 本文实证研究结果与实际获奖情况存在关联,构建的皮书影响力评价指标体系具有一定的有效性和合理性,提出了优化皮书评价的建议。