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Difference in Surface Roughness of Ethylene-Vinyl-Acetate Sheet before and after Application of Finishing Liquid: Part 2 Changes over Time in Surface Roughness
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作者 Mutsumi Takahashi Yogetsu Bando 《Materials Sciences and Applications》 2019年第6期451-460,共10页
Surface texture of the mouthguard affects the sense of adaptation in the athlete and further affects hygiene. The aim of this study was to investigate the changes over time in surface roughness after finish polishing ... Surface texture of the mouthguard affects the sense of adaptation in the athlete and further affects hygiene. The aim of this study was to investigate the changes over time in surface roughness after finish polishing of ethylene vinyl acetate (EVA) sheets and before and after finishing liquid application, and to evaluate its effectiveness. Total of 160 specimens of EVA (3 × 3 mm) were divided into 4 groups according to polishing condition (control = unpolished;RB = Robinson-brush;LF = Lisko-Fine, and MW = Mouthguard-wheel). Polishing was performed at low speed by using a straight headpiece. The rotation speed was 5000, 4000 and 6000 rpm for RB, LF, and MW, respectively. Next, a finishing liquid was applied to each specimen. Changes over time in surface roughness before and after application of the finishing liquid were compared by a non-contact surface shape measuring machine. The arithmetic average height (Sa) was measured. The measurement time points were before application, immediately after application, and at 5, 10, and 15 min after application. The changes over time of the surface roughness of the sheet before and after application of the finishing liquid were analyzed by two-way analysis of variance and Bonferroni’s multiple comparison tests. Surface roughness of the specimen before application became coarse in the order of control;MW, LF and RB, and Sa were about 0.21 μm, 2.03 μm, 2.94 μm, and 4.72 μm, respectively. That showed the same order after finishing liquid application. Significant decrease in Sa for RB and LF were seen at 10 min after application and at 5 min after application, respectively. Sa of MW was not significantly different before and after application. The results of this study showed that a lubricity of about 1.0 μm increases within 5 - 10 min of application of finishing liquid, but in cases where polishing was performed to about 2.0 μm;the application of finishing liquid has no ef-fect. 展开更多
关键词 Mouthguard Ethylene-Vinyl-Acetate Surface Roughness Polishing Method FINISHING LIQUID CHANGES over time
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Fisher's perceptions about a marine protected area over time
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作者 Cristina Pita Barbara Horta e Costa +5 位作者 Gustavo Franco Rui Coelho Inês Sousa Emanuel J.Gonçalves Jorge M.S.Gonçalves Karim Erzini 《Aquaculture and Fisheries》 2020年第5期273-281,共9页
The perceptions of fishers towards the Arrábida Marine Park,a marine protected area(MPA)in the west coast of Portugal,were studied through face-to-face interviews in two different moments of the MPA life cycle.Fi... The perceptions of fishers towards the Arrábida Marine Park,a marine protected area(MPA)in the west coast of Portugal,were studied through face-to-face interviews in two different moments of the MPA life cycle.Fishers'perceptions about the MPA and the impact it had on the fishing activity over time were identified just before the full implementation of the zoning and regulations of the management plan and 10 years later.This study aimed to investigate fishers'knowledge,acceptance and perceptions about the MPA changed with time,if support for the MPA was linked to the impact of the MPA on the fishing activity,and if fishers'perceptions about the impact of the MPA on the fishing activity match with local landings trends.Results show that although knowledge about the marine park significantly improved over time,fishers'acceptance did not.A decrease on fishers'support was not substantial but occurred.Issues such as the disagreement with regulations reinforced concerns raised during the implementation of the marine park,particularly in relation to the top-down decision-making,which commonly confers minor participation,recognition and legitimacy to fishers.Apparently,fisheries benefits were still not perceived by local fishers,though they are central for fishers'support.Further,the perceived negative impacts of the park seemed to be more related to social aspects and individual interests than to impacts on catches.Addressing adequate management,enforcement and participation of local fishers is still possible and are advocated here as to contribute to the expected socioecological outcomes and respective support,leading to the future successful performance of the Arrábida Marine Park.Assessing fishers’perceptions towards an MPA over time is central and should be included on periodical socioecological monitoring and inform an effective adaptive management. 展开更多
关键词 Arrabida Marine Park(AMP) Local fisheries PERCEPTIONS ATTITUDES Fishers'support Decision-making Marine protected area Changes over time
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Love Stories Over Time
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《Beijing Review》 2009年第43期22-22,共1页
Marriages differ for a family of women from three different generations,as told by Cao Xiuhua My mother,Li Shuyun,wasborn in Dong’e County,eastChina’s Shandong Province,
关键词 Love Stories over time
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Over Time,People ‘Catch Mood' of Friends,Lovers
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作者 Dana Frisch 郑选社 《当代外语研究》 2003年第7期3-5,共3页
笑,整个世界都跟着你笑。俗话这么说。而且,对于夫妇,对于室友而言,更是如此。一项新的研究的结果提出了这样的观点。 随着时间的过去,夫妇们及室友常常具有相似情绪反应,因此,只要经历一段时间,当你的室友或情人看电影时发出笑声,或是... 笑,整个世界都跟着你笑。俗话这么说。而且,对于夫妇,对于室友而言,更是如此。一项新的研究的结果提出了这样的观点。 随着时间的过去,夫妇们及室友常常具有相似情绪反应,因此,只要经历一段时间,当你的室友或情人看电影时发出笑声,或是对受伤的小狗眼泪汪汪的时候,你也会受其影响。 展开更多
关键词 Catch Mood over time People of Friends Lovers 婚姻关系
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Reading Faces——Our definition of what's normal changes over time
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作者 Temma Ehrenfeld 吕云 《当代外语研究》 2004年第7期34-35,共2页
爱美之心,人皆有之,但研究人员发现:Individual and social attitudes to-ward what’s acceptable,and what’s beautiful,change over time,因此尽管有Survival of the Prettiest(靓者生存)的说法,在目前轰轰烈烈的“人造”美女与帅... 爱美之心,人皆有之,但研究人员发现:Individual and social attitudes to-ward what’s acceptable,and what’s beautiful,change over time,因此尽管有Survival of the Prettiest(靓者生存)的说法,在目前轰轰烈烈的“人造”美女与帅哥的潮流中,是否选择plastic-surgery(整形手术)最好还是三思而行。 展开更多
关键词 Our definition of what’s normal changes over time Reading Faces
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A time-over-threshold technique for PMT signals processing 被引量:4
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作者 LIU Xuzong LIU Shubin AN Qi 《Nuclear Science and Techniques》 SCIE CAS CSCD 2007年第3期164-171,共8页
A novel front-end circuit designed for PMT signals processing considering the solution of "Time Walk" correction is discussed in this paper. We are trying to apply the TOT (Time over Threshold) technique to ... A novel front-end circuit designed for PMT signals processing considering the solution of "Time Walk" correction is discussed in this paper. We are trying to apply the TOT (Time over Threshold) technique to our research. Different from traditional ways, where amplitude is measured, time width is measured for slew correction here, which takes the advantage of TDC. Expensive fast ADCs are abandoned and the whole time measurement electronics design becomes more effective and economical. Test boards have been developed and a convenient method is introduced to evaluate our TOT technique. Results have shown that a 10ps slew correction resolution is achieved throughout the amplitude range from -108mV to -2000mV for negative signals of both 5 ns leading and trailing edge with 10 ns 50%-50% pulse width. 展开更多
关键词 光电倍增管 脉冲 时间测量 回转修正
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A Service-Based Intelligent Time-Domain and Spectral-Domain Flow Aggregation in IP-over-EON Based on SDON
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作者 NI Dong LI Hui +2 位作者 JI Yuefeng LI Hongbiao ZHU Yinan 《ZTE Communications》 2019年第3期56-62,共7页
The rapid growth of IP traffic has contributed to wide deployment of optical devices in elastic optical network.However,the passband shape of wavelength selective switches(WSSs)that are used in reconfigurable optical ... The rapid growth of IP traffic has contributed to wide deployment of optical devices in elastic optical network.However,the passband shape of wavelength selective switches(WSSs)that are used in reconfigurable optical add-drop multiplexer(ROADM)/optical cross connect(OXC)is not ideal,causing the narrowing of spectrum.Spectral narrowing will lead to signal impairment.Therefore,guard-bands need to be inserted between adjacent paths which will cause the waste of resources.In this paper,we propose a service-based intelligent aggregation node selection and area division(ANS-AD)algorithm.For the rationality of the aggregation node selection,the ANS-AD algorithm chooses the aggregation nodes according to historical traffic information based on big data analysis.Then the ANS-AD algorithm divides the topology into areas according to the result of the aggregation node selection.Based on the ANS-AD algorithm,we propose a time-domain and spectral-domain flow aggregation(TS-FA)algorithm.For the purpose of reducing resources'waste,the TS-FA algorithm attempts to reduce the insertion of guard-bands by time-domain and spectral-domain flow aggregation.Moreover,we design a time-domain and spectral-domain flow aggregation module on software defined optical network(SDON)architecture.Finally,a simulation is designed to evaluate the performance of the proposed algorithms and the results show that our proposed algorithms can effectively reduce the resource waste. 展开更多
关键词 IP-over-EON time-DOMAIN SPECTRAL-DOMAIN FLOW AGGREGATION big data analysis SDON
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葡萄糖添加量和卤制时间对鸭肉熟制品中WOF(warmed-over flavor)异味调控效果的影响 被引量:3
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作者 任志伟 吴巧 +1 位作者 陈煌莉 王武 《肉类研究》 2012年第1期10-13,共4页
鸭肉熟制品在冷藏后再次加热会产生WOF(warmed-over flavor)异味,为对异味进行抑制,在鸭肉加工的过程中添加还原性的葡萄糖和鸭肉中的蛋白质产生具有抗氧化性的美拉德反应产物,研究添加不同量的葡萄糖和不同的加工保持时间对WOF异味抑... 鸭肉熟制品在冷藏后再次加热会产生WOF(warmed-over flavor)异味,为对异味进行抑制,在鸭肉加工的过程中添加还原性的葡萄糖和鸭肉中的蛋白质产生具有抗氧化性的美拉德反应产物,研究添加不同量的葡萄糖和不同的加工保持时间对WOF异味抑制效果的影响,采用气相色谱-质谱联用法测定鸭肉熟制品中己醛的相对含量,以己醛的相对含量作为衡量WOF异味程度的指标,并结合感官评价进行综合分析。结果表明:在鸭肉制品加工的过程中添加葡萄糖有抑制WOF异味的作用,且随着葡萄糖添加量的增加抑制作用效果增加,加工保持时间对WOF异味的抑制效果也会产生影响,随着保持时间的延长抑制效果增加。随着葡萄糖添加量的增加及保持时间的延长会对鸭肉熟制品的口感和色泽产生不良影响,因此在加工中需进行综合分析。 展开更多
关键词 鸭肉熟制品:WOF异味 葡萄糖 保持时间 气相色谱-质谱法 感官评价
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IP over DVB中RTP视频的分析与提取 被引量:2
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作者 吴微 黄焱 《电视技术》 北大核心 2009年第S1期10-12,27,共4页
讨论了IP over DVB中RTP的视频数据的传输方式,主要是使用多协议封装(MPE),以及IP/UDP/RTP方式进行传输,最后给出了视频数据分析与提取的方法和流程。
关键词 IP over DVB 多协议封装(MPE) TCP/IP 实时传输协议
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IP over DVB中RTP音频数据的提取与恢复 被引量:6
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作者 吴微 黄焱 《信息工程大学学报》 2009年第3期379-382,共4页
IP over DVB,即DVB卫星宽带IP接入技术是通过卫星通信网络传输IP数据业务的关键技术。为了保证传输的质量,IP over DVB中的音频数据主要通过实时传输协议(RTP)承载。文章研究了IP over DVB中RTP的音频数据的传输方式,最后给出了音频数... IP over DVB,即DVB卫星宽带IP接入技术是通过卫星通信网络传输IP数据业务的关键技术。为了保证传输的质量,IP over DVB中的音频数据主要通过实时传输协议(RTP)承载。文章研究了IP over DVB中RTP的音频数据的传输方式,最后给出了音频数据提取与恢复的方法和流程。 展开更多
关键词 IP over DVB 多协议封装 实时传输协议 音频
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某电厂锅炉高温过热器爆管分析
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作者 宋理彬 《发电设备》 2025年第1期35-39,共5页
某电厂锅炉高温过热器在运行中发生爆管,为避免类似事件的发生,运用合金分析仪、布氏硬度计、金相显微镜及扫描电子显微镜(SEM)等仪器进行了宏观检验、合金成分分析、硬度测试、金相检验及能谱分析等来探究爆管原因.结果表明:本次爆管... 某电厂锅炉高温过热器在运行中发生爆管,为避免类似事件的发生,运用合金分析仪、布氏硬度计、金相显微镜及扫描电子显微镜(SEM)等仪器进行了宏观检验、合金成分分析、硬度测试、金相检验及能谱分析等来探究爆管原因.结果表明:本次爆管原因是管内壁附着较厚的腐蚀产物,引起通流面积减小,传热恶化,炉管在长期超温工况下服役.针对该问题,电厂应加强锅炉受热面管基建安装过程管理,通过做好管口封堵,以及加强运行中壁温监视等措施,提高锅炉运行可靠性. 展开更多
关键词 锅炉 高温过热器 爆管 长期超温
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Push-over分析方法基本原理及在抗震分析中的应用 被引量:1
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作者 肖成龙 张渊通 +1 位作者 李啸岚 程敏 《山西建筑》 2016年第9期65-66,共2页
介绍了Push-over分析方法的基本原理,阐述了该方法在抗震分析中的应用技巧,并将其与静力弹性分析法以及时程分析法作了比较,指出Push-over分析法对结构抗震能力的分析和设计有重要的作用。
关键词 Push-over分析法 静力弹性分析 时程分析 抗震能力
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Push-over分析方法在异形柱结构中的应用
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作者 布欣 胡五毛 张有佳 《东北电力大学学报》 2008年第1期70-75,共6页
Push-over分析方法近年来在地震工程界引起广泛兴趣,我国新的抗震设计规范已将这种方法作为大震作用下结构弹塑性分析的一种方法。影响Push-over分析结果的准确性有许多因素,其中对结构施加的侧向加载模式至关重要。采用不同的侧向加载... Push-over分析方法近年来在地震工程界引起广泛兴趣,我国新的抗震设计规范已将这种方法作为大震作用下结构弹塑性分析的一种方法。影响Push-over分析结果的准确性有许多因素,其中对结构施加的侧向加载模式至关重要。采用不同的侧向加载模式对一座12层不规则异形柱结构进行Push-over分析,并将分析结果与非线性时程分析的结果进行比较,由此给出该异形柱结构Push-over分析加载模式选取的建议。 展开更多
关键词 PUSH-over分析 侧向加载模式 异形柱结构 时程分析
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TDM over IP的发展趋势及其应用 被引量:1
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作者 刘加杰 楚纪正 王琦 《光通信技术》 CSCD 北大核心 2009年第9期9-12,共4页
论述了TDM over IP技术出现的背景、实现过程以及实际应用方案。利用伪线路仿真技术实现在以太网上传送实时业务,将语音、图像等信息直接装入以太网(或IP网)数据包,然后依照IP路由进行简单高效的传送。此技术可广泛应用于PON、基站回传... 论述了TDM over IP技术出现的背景、实现过程以及实际应用方案。利用伪线路仿真技术实现在以太网上传送实时业务,将语音、图像等信息直接装入以太网(或IP网)数据包,然后依照IP路由进行简单高效的传送。此技术可广泛应用于PON、基站回传、接口转换以及传统业务线路的改造等方面。 展开更多
关键词 TDM over IP 伪线路仿真 实时业务 IP网络
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A 16-Channel high-resolution time and charge measurement module for the external target experiment in the CSR of HIRFL 被引量:4
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作者 赵雷 康龙飞 +2 位作者 周家稳 刘树彬 安琪 《Nuclear Science and Techniques》 SCIE CAS CSCD 2014年第1期27-32,共6页
High precision time measurement is required in the readout of the neutron wall and TOF walls in the external target experiment of the Cooling Storage Ring(CSR) project in the Heavy Ion Research Facility in Lanzhou(HIR... High precision time measurement is required in the readout of the neutron wall and TOF walls in the external target experiment of the Cooling Storage Ring(CSR) project in the Heavy Ion Research Facility in Lanzhou(HIRFL).Considering the time walk correction,both time and charge are measured in the readout electronics.In this 16-channel measurement module,time and charge information are digitized by TDCs at the same time based on the Time-Over-Threshold(TOT) method;meanwhile,by employing high-density ASIC chips,the electronics complexity is effectively reduced.Test results indicate that this module achieves a time resolution better than 25 ps and a charge resolution better than 5%over the input amplitude range from 50 mV to 3V. 展开更多
关键词 时间测量 HIRFL 电荷测量 测量模块 企业社会责任 高解析度 16通道 实验
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Development of an Efficient Genetic Algorithm for the Time Dependent Vehicle Routing Problem with Time Windows 被引量:2
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作者 Suresh Nanda Kumar Ramasamy Panneerselvam 《American Journal of Operations Research》 2017年第1期1-25,共25页
This research considers the time-dependent vehicle routing problem (TDVRP). The time-dependent VRP does not assume constant speeds of the vehicles. The speeds of the vehicles vary during the various times of the day, ... This research considers the time-dependent vehicle routing problem (TDVRP). The time-dependent VRP does not assume constant speeds of the vehicles. The speeds of the vehicles vary during the various times of the day, based on the traffic conditions. During the periods of peak traffic hours, the vehicles travel at low speeds and during non-peak hours, the vehicles travel at higher speeds. A survey by TCI and IIM-C (2014) found that stoppage delay as percentage of journey time varied between five percent and 25 percent, and was very much dependent on the characteristics of routes. Costs of delay were also estimated and found not to affect margins by significant amounts. This study aims to overcome such problems arising out of traffic congestions that lead to unnecessary delays and hence, loss in customers and thereby valuable revenues to a company. This study suggests alternative routes to minimize travel times and travel distance, assuming a congestion in traffic situation. In this study, an efficient GA-based algorithm has been developed for the TDVRP, to minimize the total distance travelled, minimize the total number of vehicles utilized and also suggest alternative routes for congestion avoidance. This study will help to overcome and minimize the negative effects due to heavy traffic congestions and delays in customer service. The proposed algorithm has been shown to be superior to another existing algorithm in terms of the total distance travelled and also the number of vehicles utilized. Also the performance of the proposed algorithm is as good as the mathematical model for small size problems. 展开更多
关键词 time-DEPENDENT Vehicle ROUTING Problem GENETIC Algorithm Chromosomes CROSS-over TRAVEL timeS Vehicles
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A Full Dynamic Voltage Stability Research Based on Time-domain Simulation
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作者 Yuyao Chen Yanping Zhang +2 位作者 Jian Zhang Yanjun Zhang Lixin Song 《Energy and Power Engineering》 2013年第4期769-773,共5页
The voltage stability is substantially a dynamic stability, but the primary method which is more mature and engineering practical to analyze the stability of voltage is still static analysis. The time-domain simulatio... The voltage stability is substantially a dynamic stability, but the primary method which is more mature and engineering practical to analyze the stability of voltage is still static analysis. The time-domain simulation is an important measure in research of complex power grid. With the development of full dynamic simulation technology, the research of dynamic voltage stability by using full dynamic simulation program which is based on time-domain simulation can be carried out. This paper uses full dynamic simulation program in dynamic voltage stability research, lays special stress on research in how generator over-excitation limiter functioned and influence in dynamic voltage stability research, and raise 2 methods and steps to figure out dynamic stable voltage in both over-excitation counted and not counted. The simulation results of examples indicate the correctness and effectiveness of these methods, and also fully verify the function and influence of generator over-excitation limiter in full dynamic voltage stability research. 展开更多
关键词 Dynamic VOLTAGE STABILITY GENERATOR over-excitation LIMITER time-DOMAIN Simulation
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基于IP over DVB的DVB-H仿真系统
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作者 谢嵩 陈佳品 李振波 《微计算机信息》 2009年第19期160-162,共3页
根据对DVB-H协议中的关键技术—时间切片、多协议封装及前向纠错编码(MPE-FEC)以及相关信道编码技术的研究,设计实现了基于IP over DVB的DVB-H仿真系统。实验表明,在所设计系统中,接收端能够完全恢复DVB码流,并利用DirectShow技术实现... 根据对DVB-H协议中的关键技术—时间切片、多协议封装及前向纠错编码(MPE-FEC)以及相关信道编码技术的研究,设计实现了基于IP over DVB的DVB-H仿真系统。实验表明,在所设计系统中,接收端能够完全恢复DVB码流,并利用DirectShow技术实现了对传输码流的实时同步播放。 展开更多
关键词 DVB—H 时间切片 多协议封装及前向纠错编码 IP over DVB
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Numerical Analysis of Slag Carry-Over during Molten Steel Draining 被引量:1
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作者 Daniel Flores-Sanchez Miguel A. Barron 《Open Journal of Applied Sciences》 2017年第11期611-616,共6页
Slag carry-over during the draining of molten steel from a teeming ladle is numerically studied here. Two-phase isothermal transient 3D Computational Fluid Dynamics simulations were employed to simulate the draining p... Slag carry-over during the draining of molten steel from a teeming ladle is numerically studied here. Two-phase isothermal transient 3D Computational Fluid Dynamics simulations were employed to simulate the draining process. Two nozzle diameters, two nozzle positions and three slag heights were considered. From mass balances, the slag carry-over in terms of mass flow rate was obtained for each of the above variables. Besides, the draining times of the teeming ladle were estimated from theoretical considerations and CDF simulations, and compared. 展开更多
关键词 CFD Simulations Draining time MULTIPHASE Flow SLAG Carry-over Teeming LADLE
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Coordination of Overcurrent Relay in Distributed System for Different Network Configuration
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作者 Niraj Kumar Choudhary Soumya Ranjan Mohanty Ravindra Kumar Singh 《Journal of Power and Energy Engineering》 2015年第10期1-9,共9页
This paper presents a study on protection coordination of over current relays (OCRs) in a distributed system by considering its different operating modes. Two different case studies which are considered in present wor... This paper presents a study on protection coordination of over current relays (OCRs) in a distributed system by considering its different operating modes. Two different case studies which are considered in present work for protection coordination include: (i) DG interfaced distribution system in grid connected mode and (ii) DG interfaced distribution system in islanded mode of operation. The proposed approach is tested on the Canadian urban benchmark distribution system consisting of 9 buses. On the occurrence of fault, level of fault current changes which in turn changes the operating time of various OCRs. Therefore, it is important to calculate and suggest method of the relay setting in order to minimize the operating time of relays and also to avoid its mal-operation. In this paper, the protection scheme is optimally designed by taking into account the above mentioned conditions. The operating time of relays can be decreased and, at the same time, coordination can be maintained by considering the optimum values of time dial setting (TDS). Genetic Algorithm (GA) has been used for determining the optimum values of TDS and hence operating time. 展开更多
关键词 Distributed Generator (DG) over Current RELAYS (OCRs) time DIAL SETTING (TDS) GENETIC
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