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考虑电力系统数据治理智能化的数据库生成方法研究

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制造业自动化 2024年第2期46卷 160-165,171页

作者：张喜铭徐欢杨秋勇高伟张睿喆南方电网有限责任公司广州510000 广州信安数据有限公司广州510000

电力系统数据治理需要高质量数据库来完成其功能实施。生成复杂大电网数据库可能面临计算成本激增以及数据库信息含量不高的问题的规模。为此,提出了一种模块化和高度可扩展的方法,用于生成可高效计算的数据库。首先,利用凸松弛方法消... 详细信息

电力系统数据治理需要高质量数据库来完成其功能实施。生成复杂大电网数据库可能面临计算成本激增以及数据库信息含量不高的问题的规模。为此,提出了一种模块化和高度可扩展的方法,用于生成可高效计算的数据库。首先,利用凸松弛方法消除大量不可行点来缩减数据搜索空间。其次,基于最陡下降算法提出一种定向搜索算法,用于探索搜索空间并精确确定数据边界。然后,为了降低问题的复杂性,采用网络理论方法,识别最关键的突发事件。此外,将定向搜索高度并行化,使用并行计算来大幅减少计算时间。最后在复杂大规模系统上对所提出的方法进行了测试,并将该方法与穷举法、重要性抽样方法进行比较,测试结果表明所提出方法的计算时间不到其他方法的10%,且基于所提出方法建立的数据库比其他方法具有更高的质量,验证了所提出方法的有效性。

关键词：电网数据治理数据库机器学习

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基于平面微型线圈的单线电能传输系统研究

电力电子技术 2024年第6期58卷 102-105页

作者：张明熙毛永强李凌峰王金明内蒙古科技大学信息工程学院内蒙古包头014000 内蒙古华电玫瑰营风力发电有限公司内蒙古乌兰察布012200

研究了由两个平面特斯拉线圈构成的微型单线电能传输(SWPT)系统,在Comsol软件中对该系统进行建模和参数设定,通过仿真实验,确定了平面特斯拉线圈在SWPT方向的可实现性。重点研究了SWPT系统在不同传输距离、不同传输频率情况下对传输效... 详细信息

研究了由两个平面特斯拉线圈构成的微型单线电能传输(SWPT)系统,在Comsol软件中对该系统进行建模和参数设定,通过仿真实验,确定了平面特斯拉线圈在SWPT方向的可实现性。重点研究了SWPT系统在不同传输距离、不同传输频率情况下对传输效率的影响。并对SWPT系统模型各参数进行调整,通过改变模型初级和次级匝数,对系统传输效率进行分析。此处通过仿真实验,确定了SWPT系统最大传输效率下的各项系统参数,并通过实物实验验证了系统性能。

关键词：单线电能传输平面微型线圈传输效率

2023年7月12-13日洋县短时极端强降水过程分析

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黑龙江气象 2024年第3期41卷 13-14页

作者：张淅铭孙鹏飞李林芝洋县气象局陕西洋县723300 伊春市气象局黑龙江伊春153000 汉中市气象局陕西汉中723000

利用常规观测资料,对2023年7月12-13日发生在洋县的一次短时极端强降水过程进行诊断分析。结果表明,此次极端强降水是在副高外围,蒙古低槽冷空气和南支槽前暖空气在陕西西部交汇的背景下产生的。洋县位于副高外围的高湿环境,700 hPa比... 详细信息

利用常规观测资料,对2023年7月12-13日发生在洋县的一次短时极端强降水过程进行诊断分析。结果表明,此次极端强降水是在副高外围,蒙古低槽冷空气和南支槽前暖空气在陕西西部交汇的背景下产生的。洋县位于副高外围的高湿环境,700 hPa比湿达到13 g/kg,850 hPa比湿达到18 g/kg,低层水汽异常充沛。地面冷锋和低空切变线不仅促使低层水汽的强烈辐合,还提供了有利于强对流发展的大尺度和中尺度动力抬升作用,高空急流南侧的辐散流场也有利于加强上升运动。上冷下暖的大气不稳定层结,使强降水区上空存储了充足的潜在不稳定能量,在不稳定能量释放过程中,出现了小时雨强超过80 mm的极端强降水。

关键词：短时极端强降水西太平洋副热带高压低空切变线冷锋

光伏直驱变频多联机在严寒地区的经济性与碳排放量分析

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节能 2024年第2期43卷 39-42页

作者：朱林于文滔张喜明齐彦宇丑雪松张恒吉林建筑科技学院吉林长春130114 吉林建筑大学吉林长春130118 沈阳盛世新兴格力电器销售有限公司辽宁沈阳110100

在严寒地区,极端的气候条件和辐照强度的不稳定性给光伏直驱变频多联机的运行带来挑战。通过监测光伏直驱变频多联机在严寒地区近零能耗办公建筑中的运行情况,对实验期间的运行能耗进行分析。结果显示:光伏直驱变频多联机系统在实验期... 详细信息

在严寒地区,极端的气候条件和辐照强度的不稳定性给光伏直驱变频多联机的运行带来挑战。通过监测光伏直驱变频多联机在严寒地区近零能耗办公建筑中的运行情况,对实验期间的运行能耗进行分析。结果显示:光伏直驱变频多联机系统在实验期间的运行成本比普通多联机空调系统节省了约55.81%,经济效益显著。光伏直驱变频多联机系统的静态回收期小于10年。在建筑设计寿命20年以内,光伏直驱变频多联机系统的碳排放量比普通多联机空调系统降低了约56.95%,降碳效果明显。

关键词：光伏直驱变频多联机严寒地区近零能耗办公建筑经济性碳排放量

Manufacturing task data chain-driven production logistics trajectory analysis and optimization decision making method

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Advances in Manufacturing 2024年第1期12卷 185-206页

作者： Lin Ling Zhe-ming Song xi zhang Peng-Zhou Cao xiao-Qiao Wang Cong-Hu Liu ming-Zhou Liu School of Mechanical Engineering Hefei University of TechnologyHefei230009People’s Republic of China Guobo Electronics Co.Ltd. Nanjing211111People’s Republic of China School of Mechanical and Electronic Engineering Suzhou UniversitySuzhou234000AnhuiPeople’s Republic of China Sino-US Global Logistics Institute Shanghai Jiao Tong UniversityShanghai200030People’s Republic of China

Production logistics(PL)is considered as a critical factor that affects the efficiency and cost of production operations in discrete manufacturing *** effectively utilize manufacturing big data to improve PL efficiency and promote job shop floor economic benefits,this study proposes a PL trajectory analysis and optimization decision making method driven by a manufacturing task data chain(MTDC).First,the manufacturing task chain(MTC)is defined to characterize the discrete production process of a *** handle manufacturing big data,the MTC data paradigm is designed,and the MTDC is ***,the logistics trajectory model is presented,where the various types of logistics trajectories are extracted using the MTC as the search engine for the *** on this,a logistics efficiency evaluation indicator system is proposed to support the optimization decision making for the ***,a case study is applied to verify the proposed method,and the method determines the PL optimization decisions for PL efficiency without changing the layout and workshop equipment,which can assist managers in implementing the optimization decisions.

关键词： Production logistics(PL) Logistics trajectory analysis Logistics optimization Data driven Manufacturing task data chain(MTDC)

Analysis of root fractal characteristics in remote areas of the Taklimakan desert,China

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Forestry Studies in China 2008年第2期10卷 67-73页

作者： YANG xiao-lin zhang xi-ming LI Yi-ling LI Shao-cai SUN Hai-long xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 R R. China Graduate University of the Chinese Academy of Sciences Beijing 100039 P. R. China Sichuan Lizi Eco-technology Co. Ltd Chengdu 610031 E R. China

Fractal geometry is a potential new approach to analyze the root architecture, which may offer improved ways to quantify and summarize root system complexity as well as yield ecological and physiological insights into the functional relevance of specific architectural patterns. Fractal analysis is a sensitive measure of root branching intensity and fractal dimension expresses the ＂space filling＂ properties of a structure. The objective of this study was to find out the fractal characteristics of root systems in a remote area of the Taklimakan desert in China. The entire root system of two naturally occurring species were excavated and exposed with shov- els in 2007. The species were Tamarix taklamakanensis and Calligonum roborovskii. A one-factorial ANOVA with species as factor showed statistically a highly significant difference in fractal dimensions, indicating differences in their pattern of root branching. There was no relationship between root diameter and two parameters of fractal root models a and q, representing general characteris- tics of root systems, for either species （a： the ratio of the sum of root cross-sectional areas after a branching to the cross-sectional area before root division; q： the distribution of the cross-sectional areas after branching）. We have found significant linear relation- ships between the diameter after branching and root length and biomass respectively, because of the self-similarity of root branching. Branching rules are the same for roots of all sizes and lengths. Root biomass for the root systems of entire trees can be estimated by measuring the diameter of each root at the base of the trunk or the diameter after branching. We have shown that the diameter of each root at the base of the trunk and the diameter after branching are effective indices that can be measured easily in order to estimate the root lengths, biomass and other parameters of root architecture.

关键词： Taklimakan desert root architecture fractal dimension root length root biomass

A review of the neurotransmitter system associated with cognitive function of the cerebellum in Parkinson's disease

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Neural Regeneration Research 2024年第2期19卷 324-330页

作者： xi Chen Yuhu zhang Department of Neurology Guangdong Neuroscience InstituteGuangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhouGuangdong ProvinceChina Shantou University Medical College ShantouGuangdong ProvinceChina

The dichotomized brain system is a concept that was generalized from the‘dual syndrome hypothesis’to explain the heterogeneity of cognitive impairment,in which anterior and posterior brain systems are independent but partially *** dopaminergic system acts on the anterior brain and is responsible for executive function,working memory,and *** contrast,the cholinergic system acts on the posterior brain and is responsible for semantic fluency and visuospatial *** from dopaminergic/cholinergic imaging or functional neuroimaging has shed significant insight relating to the involvement of the cerebellum in the cognitive process of patients with Parkinson’s *** research has reported evidence that the cerebellum receives both dopaminergic and cholinergic ***,whether these two neurotransmitter systems are associated with cognitive function has yet to be fully ***,the precise role of the cerebellum in patients with Parkinson’s disease and cognitive impairment remains ***,in this review,we summarize the cerebellar dopaminergic and cholinergic projections and their relationships with cognition,as reported by previous studies,and investigated the role of the cerebellum in patients with Parkinson’s disease and cognitive impairment,as determined by functional *** findings will help us to understand the role of the cerebellum in the mechanisms underlying cognitive impairment in Parkinson’s disease.

关键词： anterior brain system cerebellum cholinergic cognitive impairment dopaminergic dual syndrome hypothesis neuroimage neurotransmitter Parkinson’s disease posterior brain system therapeutic targets

Unsatisfactory outcomes of prolonged ischemic priapism without early surgical^shunts： our clinical experience and a review of the literature

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Asian Journal of Andrology 2013年第1期15卷 75-78页

作者： Da-Chao Zheng Hai-Iun Yao Ke zhang ming-xi Xu Qi Chen Yan-Bo Chen Zhi-Kang Cai Mu-Jun Lu Zhong Wang Department of Urology Shanghai Ninth People's Hospital Shanghai Jiaotong University School of Medicine Shanghai 200011 China

Ischemic priapism is a rare occurrence which can cause severe erectile dysfunction （ED） without timely treatment. This retrospective study reports our experience in treating prolonged ischemic priapism and proposes our further considerations. In this paper, a total of nine patients with prolonged ischemic priapism underwent one to three types of surgical shunts, including nine Winter shunts, two AI-Ghorab shunts and one Grayhack shunt. During the follow-up visit （after a mean of 21.11 months）, all patients＇ postoperative characters were recorded, except one patient lost for death. Six postoperative patients accepted a 25-mg oral administration of sildenafil citrate. The erectile function of the patients was evaluated by their postoperative 5-item version of International Index of Erectile Function Questionnaire （IIEF-5）, which were later compared with their premorbid scores. All patients had complete resolutions, and none relapsed. The resolution rate was 100%. Seven patients were resolved with Winter shunts, one with an AI-Ghorab shunt and one with a Grayhack shunt. The mean hospital stay was 8.22 days. There was only one urethral fistula, and the incidence of postoperative ED was 66.67%. Four patients with more than a 72-h duration of priapism had no response to the long-term phosphodiesterase type 5 （PDE-5） inhibitor treatment. These results suggest that surgical shunts are an efficient approach to make the penis flaccid after prolonged priapism. However, the severe ED caused by prolonged duration is irreversible, and long-term PDE-5 inhibitor treatments are ineffective. Thus, we recommend early penile prosthesis surgeries for these patients.

关键词： erectile dysfunction PDE-5 inhibitor penile prosthesis surgery prolonged ischemic priapism surgical shunts

Bolstering the Mechanical Robustness of Supramolecular Polymer Network by Mechanical Bond

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Chinese Journal of Polymer Science 2024年第10期42卷 1536-1544,I0012页

作者： Yuan-Hao Wang Jing-xi Deng Jun Zhao Yi Ding Li Yang Zhao-ming zhang Xu-Zhou Yan School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai200240China Frontiers Science Center for Transformative Molecules Shanghai Jiao Tong UniversityShanghai200240China

Supramolecular polymer networks(SPNs)are celebrated for their dynamic nature,yet they often exhibit inadequate mechanical *** far,the quest to bolster the mechanical resilience of SPNs while preserving their dynamic character presents a formidable ***,we introduce[2]rotaxane into SPN to serve as another cross-link,which could effectively enhance the mechanical robustness of the polymer network without losing the dynamic *** with SPN,the dually cross-linked network(DPN)demonstrates superior breaking strength,Young’s modulus,puncture force and toughness,underscoring its superior ***,the cyclic tensile tests reveal that the energy dissipation capacity of DPN rivals,and in some cases surpasses,that of SPN,owing to the efficient energy dissipation pathway facilitated by[2]*** addition,benefiting from stable topological structure of[2]rotaxane,DPN exhibits accelerated recovery from deformation,indicating superior elasticity compared to *** strategy elevates the performance of SPNs across multiple metrics,presenting a promising avenue for the development of high-performance dynamic materials.

关键词： Rotaxane cross-links Dually cross-linked network Supramolecular polymer network Host-guest recognition Dynamic materials