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多主体参与的区域综合能源系统集中-分布式需求响应机制
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作者 董萌苇 朱勐婷 +1 位作者 徐成司 董树锋 《电网技术》 EI CSCD 北大核心 2024年第6期2336-2345,I0026-I0031,共16页
区域综合能源系统是能源互联网建设背景下能源供给体系的重要发展方向,随着城镇区域内微能源网、虚拟电厂等具备电网互动能力的新用能主体相继出现,该文针对区域综合能源系统需求响应这一重要调控问题,提出一种考虑区域系统运营商与区... 区域综合能源系统是能源互联网建设背景下能源供给体系的重要发展方向,随着城镇区域内微能源网、虚拟电厂等具备电网互动能力的新用能主体相继出现,该文针对区域综合能源系统需求响应这一重要调控问题,提出一种考虑区域系统运营商与区域内多用能主体利益协调的实现机制。首先,针对传统集中式调度在保护用户信息和控制自主权方面的不足,构建了由运营商集中调度、新用能主体分布协同的集中-分布式架构。其次,针对运营商和各新用能主体的调峰责任分配和利益协调问题,引入区域调峰需求响应市场,并设计了相应的奖惩机制,在激励用户的同时,规范市场行为。此外,考虑供能安全性和新能源不确定性,建立区域供能系统和新用能主体双层用能优化模型,实现多能互补和能源梯级利用。最后,通过算例验证了所提机制的合理性和有效性,运营商和各新用能主体获得更高收益,且数据交互量少、业务流程简便,适用于现行市场机制下的实际应用场景。 展开更多
关键词 区域综合能源系统 综合需求响应 集中-分布式架构 优化运行 多能互补
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High Order Central Schemes Applied to Relativistic Multi-Component Flow Models
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作者 Tayabia Ghaffar Muhammad Yousaf +1 位作者 Saira Sultan Shamsul Qamar 《Applied Mathematics》 2014年第8期1169-1186,共18页
The dynamics of inviscid multi-component relativistic fluids may be modeled by the relativistic Euler equations, augmented by one (or more) additional species equation(s). We use the high-resolution staggered central ... The dynamics of inviscid multi-component relativistic fluids may be modeled by the relativistic Euler equations, augmented by one (or more) additional species equation(s). We use the high-resolution staggered central schemes to solve these equations. The equilibrium states for each component are coupled in space and time to have a common temperature and velocity. The current schemes can handle strong shocks and the oscillations near the interfaces are negligible, which usually happens in the multi-component flows. The schemes also guarantee the exact mass conservation for each component, the exact conservation of total momentum, and energy in the whole particle system. The central schemes are robust, reliable, compact and easy to implement. Several one- and two-dimensional numerical test cases are included in this paper, which validate the application of these schemes to relativistic multi-component flows. 展开更多
关键词 multi-COMPONENT FLOWS RELATIVISTIC EULER Equations central Schemes HIGHER Order Accuracy
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Selection Method of Multi-Objective Problems Using Genetic Algorithm in Motion Plan of AUV 被引量:3
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作者 ZHANG Ming-jun , ZHENG Jin-xing , ZHANG Jing College of Mechanical and Electrical Engineering, Harbin Engineering University, Harbin 150001 ,China College of Computer and Information Science, Harbin Engineering University, Harbin 150001 , China 《Journal of Marine Science and Application》 2002年第1期81-86,共6页
To research the effect of the selection method of multi-objects genetic algorithm problem on optimizing result, thismethod is analyzed theoretically and discussed by using an autonomous underwater vehicle(AUV) as an o... To research the effect of the selection method of multi-objects genetic algorithm problem on optimizing result, thismethod is analyzed theoretically and discussed by using an autonomous underwater vehicle(AUV) as an object. A changingweight vtlue method is put forward and a selection formula is modified. Some experiments were implemented on an AUV.TwinBurger. The results shows that this method is effective and feasible. 展开更多
关键词 AUV multi - objective optimization GENETIC algorithm SELECTION method
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Multi-features Based Approach for Moving Shadow Detection 被引量:4
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作者 周宁 周曼丽 +1 位作者 许毅平 方宝红 《Journal of Donghua University(English Edition)》 EI CAS 2004年第6期76-80,共5页
In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving... In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence. 展开更多
关键词 MOVING SHADOW detection multi - features MOVING OBJECT DETECTION
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:39
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作者 Xiang-Qun Cui Yong-Heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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Multi-objective optimization of stamping forming process of head using Pareto-based genetic algorithm 被引量:10
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作者 周杰 卓芳 +1 位作者 黄磊 罗艳 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第9期3287-3295,共9页
To obtain the optimal process parameters of stamping forming, finite element analysis and optimization technique were integrated via transforming multi-objective issue into a single-objective issue. A Pareto-based gen... To obtain the optimal process parameters of stamping forming, finite element analysis and optimization technique were integrated via transforming multi-objective issue into a single-objective issue. A Pareto-based genetic algorithm was applied to optimizing the head stamping forming process. In the proposed optimal model, fracture, wrinkle and thickness varying are a function of several factors, such as fillet radius, draw-bead position, blank size and blank-holding force. Hence, it is necessary to investigate the relationship between the objective functions and the variables in order to make objective functions varying minimized simultaneously. Firstly, the central composite experimental(CCD) with four factors and five levels was applied, and the experimental data based on the central composite experimental were acquired. Then, the response surface model(RSM) was set up and the results of the analysis of variance(ANOVA) show that it is reliable to predict the fracture, wrinkle and thickness varying functions by the response surface model. Finally, a Pareto-based genetic algorithm was used to find out a set of Pareto front, which makes fracture, wrinkle and thickness varying minimized integrally. A head stamping case indicates that the present method has higher precision and practicability compared with the "trial and error" procedure. 展开更多
关键词 冲压成形工艺 多目标优化 遗传算法 响应面模型 目标函数 最佳工艺参数 问题转化 厚度变化
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A Comparative Study of Acute Hemodynamic Effects of Multi -site Cardiac Pacing in patients with cardiac function NYHA class ⅠtoⅡ without bundle branch block 被引量:2
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作者 朱参战 崔长琮 +5 位作者 张全发 薛小临 刘维维 刘引会 《South China Journal of Cardiology》 CAS 2001年第2期101-105,共5页
Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS ... Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS 7, Ⅲ°AVB 5) undergoing pacemaker implantation. Right ventricular apex (RVA), right ventricular outflow tract (RVOT), right ventricular bifocal (RV-Bi), left ventricular base (LVB) and bi -ventricular (Bi-Ⅴ) pacing at 60 -80 ppm were done in VVI mode prior to implantation of DDD pacemaker. The cardiac index (CI), mean pulmonary artery pressure (mPAP) and pulmonary capillary wedge pressure (PCWP) were measured with Swan - Ganz thermodilution catheter after 5 minutes of each pacing mode. Results (1) Comparing to pacing at RVA (CI: 2. 41± 0. 38 L/min per m2, PCWP: 16. 7 ±3.3 mmHg), the CI increased and the PCWP decreased significantly in pacing at RVOT(CI: 2. 63 ± 0.46, PCWP: 13. 8±2. 3), LVB(CI: 2. 78±0.52, PCWP: 14. 4±3.1), RV-Bi(CI: 2. 83±0.57, PCWP: 12. 8± 2. 5) and Bi -Ⅴ pacing (CI: 2. 94± 0.60, PCWP: 12. 7±2. 5), P < 0. 01, respectively. (2) The CI of RV-Bi and Bi-Ⅴ pacing was higher than that of RVOT and LVB pacing, the PCWP was lower, P < 0. 05, respectively. (3) There was no significant difference between RV - Bi pacing and Bi-Ⅴ pacing in CI and PCWP. Conclusion There is no significant difference between RV - Bi pacing and Bi -V pacing in the acute hemodynamic effects; however,dual - site pacing is much better than single site pacing in that aspect for patients with cardiac function NYHA class Ⅰ to Ⅱ without BBB. Among single site pacing, the RVOT and LVB pacing is better than RVA pacing in cardiac function. 展开更多
关键词 multi - site cardiac pacingHemodynamics
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Research on A Master - slave Multi - microcomputers Control System for Hollow Spindle Fancy Yarn Spinning Machine
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作者 李志蜂 陈子展 阵瑞琪 《Journal of China Textile University(English Edition)》 EI CAS 1999年第1期49-52,共4页
In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardwar... In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardware construction, is introduced. Spinning experiments show that the system achieves satisfactory result. This system can solve the diftkultles of mechatronical fusion between domestic hollow splndk fancy yarn spuming muchine and its microcomputer control technology. 展开更多
关键词 hollow SPINDLE FANCY YAM spinning machine mechatrvnical fusion MASTER - SLAVE multi - microcomputers control system PC - BUS.
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On the Representation of Multi-layer Woven Structure
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作者 易洪雷 丁辛 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期14-16,共3页
A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the rein... A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the reinforcement of textile composites, the relationships among the structural parameters are derived for different binding patterns of the fabric structure. The conditions, which meet the requirements of structural cell stability,are also discussed. 展开更多
关键词 multi - layer woven FABRIC structural parame-ter BINDING PATTERN TEXTILE composite .
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Computer-aided Pattern Design of Multi-bar Warp Knitted Fabrics
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作者 李炜 《Journal of China Textile University(English Edition)》 EI CAS 2000年第1期85-87,共3页
To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the ... To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the computer-aided pattern design of multi-barwarp knitted fabrics.In terms of the special propertiesof the computer-aided pattern design of multi-barwarp knitted fabrics,the Object Oriented Program(OOP)programming-Object Windows class Library(OWL)programming is selected.According to thecharacters of the OWL programming,various functionsare defined.Pattern design and technical parameters canbe output,which offers a great convenience for the fac-tory. 展开更多
关键词 multi - bar WARP KNITTED fabric computer -aided PATTERN design PATTERN Object Windows class Library (OWL) programming.
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Evaluation of the Third 90 of the 90-90-90 Cascade for the Period 2019-2020 in the Central African Republic
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作者 Gilles Stéphane Landry Ngaya Brice Martial Yambiyo +5 位作者 Alain Farra Pulchérie Pelembi Aubin Bere Davy Golongba Steve Kamadom Alain Berlioz-Arthaud 《World Journal of AIDS》 2021年第4期189-198,共10页
<strong>Introduction</strong> In Central-African Republic, according to UNAIDS in 2019, out of approximately 100,000 people living with HIV, 70% (72,000) knew their HIV status and 47,000 (46%) were on ARV ... <strong>Introduction</strong> In Central-African Republic, according to UNAIDS in 2019, out of approximately 100,000 people living with HIV, 70% (72,000) knew their HIV status and 47,000 (46%) were on ARV therapy;however, there is a paucity of data on viral load suppression in people on ARV therapy. The objective of this study was to assess the third 90 of the UNAIDS strategy for the years 2019 and 2020 in the CAR. <strong>Methods</strong> We analyzed the available viral load data extracted from the data base of the medical analysis laboratory (SYSLAM) of the Institut Pasteur of Bangui for the years 2019 and 2020. The viral loads were determined based on plasma collected in an EDTA tube with Cepheid’s GeneXpert<sup><span style="white-space:nowrap;">&#174;</span></sup> 16-module controllers. Viral load data were extracted from SYSLAM, converted to Excel format, and analyzed with STATA version 14 software. The significance threshold for the statistical tests was set at 5%. <strong>Results</strong> This study included 22,895 patients, of who 72% were female. The average age was 40.82 years, and the majority of the patients (80%) came from the city of Bangui. Regarding the virological parameters associated with this study, 66% of the patients had significant viral load suppression according to the WHO recommendations and 34% were in virological failure. Patients over 50 years of age (71.85%) and age group 40 - 49 years (69.25%) recorded significant levels of viral load suppression. On the other hand, 63.45% of patients under 18 years of age had virological failure. All of these results were statistically significant (p < 0.005). <strong>Conclusion</strong> There should be a concerted effort, to make viral load accessible and available to all patients receiving ARV treatment in the CAR and the management of HIV/AIDS infection of children and adolescents should be given special attention. 展开更多
关键词 HIV ARV Viral Load Suppression 90-90-90 Target central African Republic
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基于多元宇宙优化算法的混合光伏-热电系统MPPT设计
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作者 李大虎 周泓宇 +2 位作者 周悦 饶渝泽 姚伟 《中国电力》 CSCD 北大核心 2023年第11期197-205,共9页
混合光伏-热电(centralized hybrid photovoltaic thermoelectric generator,PV-TEG)系统在部分遮蔽(partial shading condition,PSC)条件下呈现多个局部最大功率点(local maximum power point,LMPP)。采用多元宇宙优化算法(multi-verse... 混合光伏-热电(centralized hybrid photovoltaic thermoelectric generator,PV-TEG)系统在部分遮蔽(partial shading condition,PSC)条件下呈现多个局部最大功率点(local maximum power point,LMPP)。采用多元宇宙优化算法(multi-verse optimization,MVO),用于PV-TEG系统在PSC下的最大功率点跟踪(maximum power point tracking,MPPT)。MVO通过平衡全局搜索和局部搜索,有效识别多个LMPPs中唯一的全局最大功率点(global maximum power point,GMPP),避免搜索结果陷入LMPP,以提高发电效率和能源利用率。算例仿真结果表明:基于MVO的MPPT可以在更短的时间内收集到更高的功率,实现功率波动最小。 展开更多
关键词 混合光伏-热电系统 最大功率点跟踪 多元宇宙优化算法 部分遮蔽
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Multi-level gait transition model for a new type of arthropod robot
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作者 常青 韩宝玲 +1 位作者 罗庆生 那奇 《Journal of Beijing Institute of Technology》 EI CAS 2013年第4期454-460,共7页
To realize the continuous and variable gait transition for a new type of arthropod robot, a multi-level gait transition model is studied in this paper. The model is composed of central pattern generator (CPG) and sa... To realize the continuous and variable gait transition for a new type of arthropod robot, a multi-level gait transition model is studied in this paper. The model is composed of central pattern generator (CPG) and saturation function. The CPG consists of four pairs of oscillators which can ex- hibit rhythmic activity when given stimulation signal S that lies in the range of saturation function. All oscillators receive the same S, but each pair of oscillators has different saturation functions. Multi- level gait transition can be realized when S changes regularly, as the oscillators start or stop oscilla- ting at different times. After computer simulation, the gait transition model is implemented in the ar- thropod robot. The experimental results show that ideal gait transition for the arthropod robot can be realized with the multi-level gait transition model. 展开更多
关键词 multi-level gait transition central pattern generator CPG saturation function ar-thropod robot
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基于物联网的多院区病区中央监护系统的建设实践
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作者 褚永华 张杰 +8 位作者 张鞠成 徐洪良 顾政 邹瞿超 黄天海 杨燕 赵立飞 兰美娟 王志康 《中国医院建筑与装备》 2024年第1期73-78,共6页
基于目前医院普通病区患者生命体征监测现状,设计开发了基于物联网的多院区病区中央监护系统,在病区床旁通过PDA扫码实现监护仪与患者绑定和解绑。病区中央监护系统与护理综合信息平台通过接口对接,患者生命体征定时发送到护理综合信息... 基于目前医院普通病区患者生命体征监测现状,设计开发了基于物联网的多院区病区中央监护系统,在病区床旁通过PDA扫码实现监护仪与患者绑定和解绑。病区中央监护系统与护理综合信息平台通过接口对接,患者生命体征定时发送到护理综合信息平台,实现了普通病区患者生命体征实时监测。通过基于物联网的多院区病区中央监护系统的应用,显著减少了护士工作量,提高了护士工作效率。 展开更多
关键词 智慧病房 物联网 多院区管理 中央监护系统
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多色无纺布包装材料在手术器械灭菌管理中的应用效果
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作者 夏月 骆金铠 袁园 《中国医学装备》 2024年第3期174-177,共4页
目的:分析多色无纺布包装材料在手术器械灭菌管理对手术周转效率、手术器械准备情况及外科医护人员与患者满意度等影响。方法:选取2016年3月至2021年12月首都医科大学附属北京友谊医院消毒供应中心的31589件手术器械,根据管理方法不同,... 目的:分析多色无纺布包装材料在手术器械灭菌管理对手术周转效率、手术器械准备情况及外科医护人员与患者满意度等影响。方法:选取2016年3月至2021年12月首都医科大学附属北京友谊医院消毒供应中心的31589件手术器械,根据管理方法不同,将2016年3月至2019年1月的71007例手术患者及患者使用的16224件手术器械纳入对照组,采用传统的纱棉布包包装手术器械管理方法。将2019年2月至2021年12月的62548例手术患者及患者使用的15365件手术器械纳入观察组,采用多色无纺布包装材料手术器械管理方法,比较两组手术周转效率、手术器械准备情况及患者与外科医护人员的使用管理满意度。结果:观察组患者手术的入室时间、入室-切皮时间、接台手术入室-切皮时间及手术延误率均低于对照组,差异有统计学意义(t=52.681、37.167、72.524,χ^(2)=9.605,P<0.05)。与对照组比较,观察组外出送物品次数、装配错误和器械丢失明显降低,器械完好件数明显提高,差异有统计学意义(χ^(2)=107.345、11.782、8.727、66.223,P<0.05);观察组患者及医护人员器械使用管理的满意度显著高于对照组,差异有统计学意义(t=100.723、6.756,P<0.05)。结论:手术器械运用多色无纺布包装材料有助于提高手术周转率,通过降低外出送物品次数、装配错误及器械丢失提高消毒供应中心工作效率,改善外科医护人员与患者对手术器械多色无纺布包装材料的满意度。 展开更多
关键词 多色无纺布 手术器械 管理 消毒供应中心 满意度
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多学科协作风险管控预防肿瘤病人PICC相关性静脉血栓的效果观察
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作者 孙媛媛 倪春湘 +2 位作者 赵浩 马丽 仲畅 《循证护理》 2024年第7期1249-1252,共4页
目的:探讨多学科协作(MDT)风险管控预防肿瘤病人经外周静脉置入中心静脉导管(PICC)相关性静脉血栓的效果。方法:选取2020年6月—2022年6月在本院留置PICC的肿瘤病人190例,采用随机数字表法分为观察组和对照组,各95例。对照组给予常规护... 目的:探讨多学科协作(MDT)风险管控预防肿瘤病人经外周静脉置入中心静脉导管(PICC)相关性静脉血栓的效果。方法:选取2020年6月—2022年6月在本院留置PICC的肿瘤病人190例,采用随机数字表法分为观察组和对照组,各95例。对照组给予常规护理,观察组在对照组基础上给予MDT风险管控护理,比较两组PICC穿刺、维护质量、相关性静脉血栓及腋下静脉最大血流速度(Vmax),平均血流速度(Vmean)情况。结果:观察组PICC一次穿刺成功率、维护质量优良率高于对照组(P<0.05);两组护理后腋下静脉Vmax、Vmean快于护理前,观察组护理后腋下静脉Vmax、Vmean快于对照组(P<0.05);观察组PICC相关性静脉血栓发生率为2.11%,低于对照组的11.58%(P<0.05)。结论:MDT风险管控可提高肿瘤病人PICC穿刺、维护质量,改善腋下静脉循环,有利于改善PICC相关性静脉血栓的预防效果。 展开更多
关键词 多学科协作 预防 肿瘤 经外周静脉置入中心静脉导管 静脉血栓 护理
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基于改进图注意力网络的油井产量预测模型
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作者 张强 彭骨 薛陈斌 《吉林大学学报(理学版)》 CAS 北大核心 2024年第4期933-942,共10页
针对图注意力网络处理噪声和时序数据较弱,并且在堆叠多层后出现梯度爆炸、过平滑等问题,提出一种改进图注意力网络模型.首先,使用Squeeze-and-Excitation模块对样本输入数据的特征信息进行不同程度关注,增强模型处理噪声的能力;其次,... 针对图注意力网络处理噪声和时序数据较弱,并且在堆叠多层后出现梯度爆炸、过平滑等问题,提出一种改进图注意力网络模型.首先,使用Squeeze-and-Excitation模块对样本输入数据的特征信息进行不同程度关注,增强模型处理噪声的能力;其次,使用多头注意力机制,将序列数据中每个序列相对其他序列进行加权求和,提取数据的时序性;再次,将图注意力网络提取的节点特征与节点的度中心性拼接,获取节点的局部特征,并用全局平均池化的方式提取节点的全局特征;最后,将两者进行融合得到节点的最终特征表示,增强模型的表征能力.为验证改进图注意力网络的有效性,将改进图注意力网络模型与LSTM,GRU和GGNN模型进行对比,实验结果表明,该模型预测效果得到有效提升,具有更高的预测精度. 展开更多
关键词 图注意力网络 多头注意力 节点度中心性 全局平均池化
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基于单/多智能体简化强化学习的电力系统无功电压控制 被引量:1
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作者 马庆 邓长虹 《电工技术学报》 EI CSCD 北大核心 2024年第5期1300-1312,共13页
为了快速平抑分布式能源接入系统产生的无功电压波动,以强化学习、模仿学习为代表的机器学习方法逐渐被应用于无功电压控制。虽然现有方法能实现在线极速求解,但仍然存在离线训练速度慢、普适性不够等阻碍其应用于实际的缺陷。该文首先... 为了快速平抑分布式能源接入系统产生的无功电压波动,以强化学习、模仿学习为代表的机器学习方法逐渐被应用于无功电压控制。虽然现有方法能实现在线极速求解,但仍然存在离线训练速度慢、普适性不够等阻碍其应用于实际的缺陷。该文首先提出一种适用于输电网集中式控制的单智能体简化强化学习方法,该方法基于“Actor-Critic”架构对强化学习进行简化与改进,保留了强化学习无需标签数据与强普适性的优点,同时消除了训练初期因智能体随机搜索造成的计算浪费,大幅提升了强化学习的训练速度;然后,提出一种适用于配电网分布式零通信控制的多智能体简化强化学习方法,该方法将简化强化学习思想推广形成多智能体版本,同时采用模仿学习进行初始化,将全局优化思想提前注入各智能体,提升各无功设备之间的就地协同控制效果;最后,基于改进IEEE 118节点算例的仿真结果验证了所提方法的正确性与快速性。 展开更多
关键词 无功电压控制 集中式控制 单智能体简化强化学习 分布式控制 多智能体简化强化学习
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西菲律宾海盆的构造沉积特征及对海盆演化的指示--来自地球物理大断面的证据 被引量:7
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作者 董冬冬 张正一 +2 位作者 张广旭 白永良 范建柯 《海洋与湖沼》 CAS CSCD 北大核心 2017年第6期1415-1425,共11页
菲律宾海发育了全球最典型的沟弧盆体系,新老俯冲系统众多,是研究大洋板块扩张过程的理想场所。本文主要利用2015年中科院海洋所在西菲律宾海采集的1400km地球物理大断面,并结合最新的重力数据,对比、分析了西菲律宾海内部古扩张中心(... 菲律宾海发育了全球最典型的沟弧盆体系,新老俯冲系统众多,是研究大洋板块扩张过程的理想场所。本文主要利用2015年中科院海洋所在西菲律宾海采集的1400km地球物理大断面,并结合最新的重力数据,对比、分析了西菲律宾海内部古扩张中心(中央海盆裂谷)和残留弧(九州-帕劳海脊)的沉积地貌和地壳结构特征。研究表明:(1)中央海盆裂谷内部发育远洋沉积为主的沉积物,沉积层序分布不均,局部盆地内沉积物厚度可达300m。九州-帕劳海脊附近发育与火山碎屑物源有关的厚层沉积物;(2)以129°30′E处的转换断层为界,裂谷东西部洋壳结构分别体现"慢速"和"快速"扩张特征,东部洋壳岩浆供应较少,厚度较小,断裂较为发育,其附近可能发生水岩作用;西部洋壳岩浆供应较多,厚度较大,结构相对均一;盆地西部的小规模地幔柱可能控制了裂谷东西部不同洋壳结构的发育;(3)九州-帕劳海脊内的角度不整合面代表岛弧裂解事件,张裂与挤压构造共同发育反映了裂解过程的复杂性。 展开更多
关键词 中央海盆裂谷 九州-帕劳海脊 多道地震 地壳结构 地幔柱
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替加环素联合头孢哌酮/舒巴坦钠治疗多重/泛耐药鲍曼不动杆菌中枢神经系统感染有效性及安全性的Meta分析
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作者 陆陶俊进 赵明娟 +4 位作者 王伟 潘智勇 胡琴 李一荣 李志强 《医药导报》 CAS 北大核心 2024年第1期131-136,共6页
目的 评价替加环素联合头孢哌酮/舒巴坦钠治疗多重/泛耐药鲍曼不动杆菌(MDRAB/XDRAB)中枢系统感染的效果和安全性,为MDRAB/XDRAB中枢神经系统感染的抗菌药物治疗提供循证学依据。方法 计算机系统检索万方数据库、中国生物医学文献数据... 目的 评价替加环素联合头孢哌酮/舒巴坦钠治疗多重/泛耐药鲍曼不动杆菌(MDRAB/XDRAB)中枢系统感染的效果和安全性,为MDRAB/XDRAB中枢神经系统感染的抗菌药物治疗提供循证学依据。方法 计算机系统检索万方数据库、中国生物医学文献数据库、维普中文科技期刊数据库、中国国家知识基础设施(CNKI)及Pubmed、Embase和Cochrane Library数据库,检索建库至2022年9月1日公开发表的有关替加环素及头孢哌酮/舒巴坦钠治疗MDRAB/XDRAB中枢神经系统感染的随机对照试验(RCT)文献。对纳入研究的文献使用Cochrane协作网偏倚风险评价工具进行质量评价,提取有效数据后采用RevMan5.4版软件进行Meta分析。结果 初筛文献184篇,最终纳入中文RCT研究4篇,样本量267例。Meta分析显示,联合疗法对MDRAB/XDRAB中枢神经系统感染的总疗效可能优于单药疗法[OR=4.30,95%CI=(1.93,9.58),P<0.01]。联合疗法对于细菌的清除有更好的效果[OR=4.20,95%CI=(2.08,8.48),P<0.01],且联合疗法产生的不良反应更少[OR=0.19,95%CI=(0.05,0.67),P<0.05]。联合疗法与单药疗法的治愈率差异无统计学意义(P>0.05)。结论 替加环素联合头孢哌酮/舒巴坦钠治疗MDRAB/XDRAB中枢神经系统感染较单药治疗可能有更好的临床疗效和安全性,受限于纳入研究的数量及质量,尚待更多更高质量的研究予以验证。 展开更多
关键词 替加环素 头孢哌酮/舒巴坦钠 多重/泛耐药鲍曼不动杆菌 中枢神经系统感染 META分析
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