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Seamless handover between unicast and multicast multimedia streams

Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第10期15卷 929-942页

作者： Mau-Luen THAM Chee-Onn CHOW Yi-han XU Khong Neng choong Cheng Suan LEE Department of Electrical Engineering Faculty of Engineering University of Malaya College of Information Science and Technology Nanjing Forestry University Wireless Communication Cluster MIMOS BerhadKuala Lumpur 57000 Malaysia Power-All Networks Jalan AmpangKuala Lumpur 50450 Malaysia

With the deployment of heterogeneous networks, mobile users are expecting ubiquitous connectivity when using applications. For bandwidth-intensive applications such as Internet Protocol Television(IPTV), multimedia contents are typically transmitted using a multicast delivery method due to its bandwidth efficiency. However, not all networks support multicasting. Multicasting alone could lead to service disruption when the users move from a multicast-capable network to a non-multicast network. In this paper, we propose a handover scheme called application layer seamless switching(ALSS) to provide smooth real-time multimedia delivery across unicast and multicast networks. ALSS adopts a soft handover to achieve seamless playback during the handover period. A real-time streaming testbed is implemented to investigate the overall handover performance, especially the overlapping period where both network interfaces are receiving audio and video packets. Both the quality of service(QoS) and objective-mapped quality of experience(QoE) metrics are measured. Experimental results show that the overlapping period takes a minimum of 56 and 4 ms for multicast-to-unicast(M2U) and unicast-to-multicast(U2M) handover, respectively. The measured peak signal-to-noise ratio(PSNR) confirms that the frame-by-frame quality of the streamed video during the handover is at least 33 dB, which is categorized as good based on ITU-T recommendations. The estimated mean opinion score(MOS) in terms of video playback smoothness is also at a satisfactory level.

关键词： Experimental approach Multimedia session continuity Seamless handover Unicast/multicast switching Multimedia streaming

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Univector field method-based multi-agent navigation for pursuit problem in obstacle environments

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Journal of Central South University 2017年第4期24卷 1002-1012页

作者： Le Pham Tuyen Hoang Huu Viet Sang Hyeok An Seung Gwan Lee Dong-Han Kim Tae choong Chung Department of Computer Science and Engineering Kyung Hee University Yongin Gyeonggi 446-701 Korea Department of Information Technology Vinh University 182-Le Duan Vinh City Nghe An 461056 Vietnam Humanitas College Kyung Hee University Yongin Gyeonggi 446-701 Korea Department of Electronics and Radio Engineering Kyung Hee University Yongin Gyeonggi 446-701 Korea

The pursuit problem is a well-known problem in computer science. In this problem, a group of predator agents attempt to capture a prey agent in an environment with various obstacle types, partial observation, and an infinite grid-world. Predator agents are applied algorithms that use the univector field method to reach the prey agent, strategies for avoiding obstacles and strategies for cooperation between predator agents. Obstacle avoidance strategies are generalized and presented through strategies called hitting and following boundary(HFB); trapped and following shortest path(TFSP); and predicted and following shortest path(PFSP). In terms of cooperation, cooperation strategies are employed to more quickly reach and capture the prey agent. Experimental results are shown to illustrate the efficiency of the method in the pursuit problem.

关键词： pursuit problem predator agent prey agent univector field method multi-agent systems

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Forty hours with a traumatic carotid transection： A diagnostic caveat and review of the contemporary management of penetrating neck trauma

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Chinese Journal of Traumatology 2018年第2期21卷 118-121页

作者： Eugene Ng Ian Campbell Andrew choong Allan Kruger Philip J. Walker Department of Vascular Surgery Royal Brisbane & Women's Hospital Herston QLD 4006 Brisbane Australia

尽管渗透颈损伤(PNT ) 是不平常的，它与重要病态和死亡被联系。PNT 的管理在过去的 50 年显著地变化了。一个放射学的评价现在是有传统的外科的探索的管理的重要部分。22 岁男性被一把螺丝刀袭击并且支撑了多重渗透的颈损害。对比 CT ... 详细信息

尽管渗透颈损伤(PNT ) 是不平常的，它与重要病态和死亡被联系。PNT 的管理在过去的 50 年显著地变化了。一个放射学的评价现在是有传统的外科的探索的管理的重要部分。22 岁男性被一把螺丝刀袭击并且支撑了多重渗透的颈损害。对比 CT 扫描在左普通颈动脉动脉灯泡揭示了焦点的 pseudoaneurysm。没有活跃流血或任何另外的脉管的损害，病人仍然保持 haemodynamically 稳定。鉴于这些调查结果，没有开的外科的探索，他开始保存地被管理。然而，病人被注意一夜间在他的血红素计数有尖锐落下指导 angiography 看了从 pseudoaneurysm 的活跃流血的柱子损害和导管。40 个小时后面的外科的探索起始的损害通过与一个大 saphenous 静脉补丁被修理的左颈动脉灯泡的两面动脉的墙揭示了渗透的损害。一根经皮的排水管在颈动脉三角被插入，为五天的静脉内的抗菌素的一堂功课被开始。病人没有复杂并发症恢复了很好并且在五个月后续行动仍然保持无征状。

关键词：颈动脉管理渗透损伤小时评论诊断创伤

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Ischemic colitis after enema administration: Incidence, timing, and clinical features

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World Journal of Gastroenterology 2020年第41期26卷 6442-6454页

作者： Yura Ahn Gil-Sun Hong Ju Hee Lee choong Wook Lee Seon-Ok Kim Department of Radiology and Research Institute of Radiology University of Ulsan College of Medicine&Asan Medical CenterSeoul 05505South Korea Department of Clinical Epidemiology and Biostatistics Asan Medical CenterUniversity of Ulsan College of MedicineSeoul 05505South Korea

BACKGROUND Enema administration is a common procedure in the emergency department(ED). However, several published case reports on enema-related ischemic colitis(IC) have raised the concerns regarding the safety of enema agents. Nevertheless, information on its true incidence and characteristics are still *** To investigate the incidence, timing, and risk factors of IC in patients receiving *** We consecutively collected the data of all adult patients receiving various enema administrations in the ED from January 2010 to December 2018 and identified patients confirmed with IC following enema. Of 8320 patients receiving glycerin enema, 19 diagnosed of IC were compared with an age-matched control group without *** The incidence of IC was 0.23% among 8320 patients receiving glycerin enema;however, there was no occurrence of IC among those who used other enema agents. The mean age ± standard deviation(SD) of patients with glycerin enemarelated IC was 70.2 ± 11.7. The mean time interval ± SD from glycerin enema administration to IC occurrence was 5.5 h ± 3.9 h(range 1-15 h). Of the 19 glycerin enema-related IC cases, 15(79.0%) were diagnosed within 8 h. The independent risk factors for glycerin-related IC were the constipation score [Odds ratio(OR), 2.0;95% confidence interval(CI): 1.1-3.5, P = 0.017] and leukocytosis(OR, 4.5;95%CI: 1.4-14.7, P = 0.012).CONCLUSION The incidence of glycerin enema-related IC was 0.23% and occurred mostly in the elderly in the early period following enema administration. Glycerin enemarelated IC was associated with the constipation score and leukocytosis.

关键词： Enema Glycerin Ischemic colitis Incidence Timing Risk factors

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Does the discrepancy in histologic differentiation between a forceps biopsy and an endoscopic specimen necessitate additional surgery in early gastric cancer?

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World Journal of Gastrointestinal Oncology 2017年第8期9卷 319-326页

作者： Jae Seung Soh Hyun Lim Ho Suk Kang Jong Hyeok Kim Kab choong Kim Department of Internal Medicine University of Hallym College of Medicine Hallym University Sacred Heart Hospital Department of Surgery University of Hallym College of Medicine Hallym University Sacred Heart Hospital

AIM To investigate the clinicopathological variables in early gastric cancer(EGC) patients in relation to differentiation *** The data of 265 specimens from 240 patients with EGC, who had undergone radical operation at Hallym University Sacred Heart Hospital from 2010 to 2015, were retrospectively analyzed. We evaluated clinical, endoscopic, and histopathological data according to histological *** Clinically significant discrepancy rate showed the difference in differentiated type(well and moderately differentiated) and undifferentiated type(poorly differentiated and signet ring cell) between endoscopic biopsies and postoperative specimens was 9.4%(25/265). There were no differences in tumor location, size, gross pattern, and number of biopsies. Specimens having histological discrepancy showed more submucosal invasion(72.0% vs 49.6%, P = 0.033) and lymph node involvement(24.0% vs 7.9%, P = 0.009) than specimens having non-discrepancy. The rate of a positive epidermal growth factor receptor status was higher in specimens having discrepancy than in specimens having non-discrepancy(81.0% vs 55.4%, P = 0.035).CONCLUSION The discordance of histologic differentiation is associated with higher submucosal invasion and lymph node metastases in EGC. Patients have histological discrepancy may require additional surgical treatments.

关键词：早胃的癌症组织学的差异区别 Clinicopathological 因素内视镜的治疗外科的治疗

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Effects of temperature and solvent concentration on the solvent crystallization of palm-based dihydroxystearic acid with isopropyl alcohol

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Particuology 2012年第1期10卷 127-131页

作者： Gregory F.L. Koay Teong-Guan Chuah Sumaiya Zainal-Abidin Salmiah Ahmad Thomas S.Y. choong Department of Chemical and Environmental Engineering Universiti Putra Malaysia Advanced Oleochemical Technology Division Malaysian Palm Oil Board Institute of Tropical Forestry and Forest Products Universiti Putra Malaysia Faculty of Chemical and Natural Resources Engineering Universiti Malaysia Pahang Director General's Office Malaysian Rubber Board

Palm-based dihydroxystearic acid of 69.55% purity was produced in a 500-kg-per-batch operation pilot plant and purified through solvent crystallization in a custom fabricated simultaneous batch crystallizer unit. The effects of temperature and solvent concentration on yield, particle size distribution and purity were studied. The purity was higher, while the yield and particle size were lower and smaller, respectively, at higher temperature and solvent concentration. The solvent crystallization process efficiency was rated at 66-69% when carried out with 70-80% isopropyl alcohol at 20℃.

关键词： Dihydroxystearic acidPilot plant operationSolvent crystallizationSimultaneous batch crystallizerProcess efficiency

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Purifying behavior of photocatalytic TiO_2 anodized in nitrate ion containing solution

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中国有色金属学会会刊：英文版 2009年第4期19卷 1027-1030页

作者： Jin-Wook CHOI Seong-Eun LEE Byung-Gwan LEE Yong-Soo JEONG Han-Jun OH choong-Soo CHI School of Advanced Materials Engineering Kookmin University Korea Institute of Materials Science Department of Materials Science Han seo University

Mesoporous titanium dioxide films were fabricated on titanium plates by micro-arc oxidation *** increase the photocatalytic activity of the films,NH4NO3 was added to the H2SO4 solution,and anodizing was carried out at high voltages using a DC power *** crystal structure,chemical composition,surface morphology and the optical property of the films were investigated by XPS,XRD,UV-VIS spectroscopy and *** photocatalytic activity of the films was evaluated by the decomposition of aniline blue,and the activity of the films for the degradation turned out to be improved by the additives to the electrolyte *** enhanced photocatalytic activity might result from the increased porosity and nitrate ion incorporation into the anodic films by micro arcing,and thereby the TiO2 layer might exhibit an improved absorption property for the visible light.

关键词：二氧化钛硝酸溶液盐离子催化行为氧化钛薄膜光催化活性 H2SO4溶液净化

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Formation behavior of anodic TiO_2 nanotubes in fluoride containing electrolytes

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中国有色金属学会会刊：英文版 2009年第4期19卷 842-845页

作者： Byung-Gwan LEE Jin-Wook CHOI Seong-Eun LEE Yong-Soo JEONG Han-Jun OH choong-Soo CHI School of Advanced Materials Engineering Kookmin University Korea Institute of Materials Science Department of Materials Science Han seo University

TiO2 nanotube layers can be formed with titanium in the electrolytes containing fluoride by electrochemical *** role of fluoride ion,the crystallinity of the anodic oxide,and the chemical state were *** results show the anodic film is composed of oxide and a little amount of *** presence of F- ions leads to chemical dissolution of Ti oxide layer and prevents hydroxide ***,chemical dissolution rate increases with increasing the fluoride content in the range of 0-2%(in mass fraction) because F- ions in electrolyte attack the interface and allow the ions of the electrolyte to easily penetrate into the *** as-anodized TiO2 nanotubes exhibit an amorphous *** treated nanotubes are composed of mixtures of the anatase and rutile phases.

关键词： TiO2纳米管阳极氧化处理氟离子电解质行为二氧化钛化学溶解电化学方法

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Neurodegenerative changes initiated by presynaptic dysfunction

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Translational Neurodegeneration 2013年第1期2卷 108-112页

作者： Toru Yasuda Yasuto Nakata Chi-Jing choong Hideki Mochizuki Department of Neurology Osaka University Graduate School of MedicineSuitaOsakaJapan Present address:Department of Genetics National Center for Child Health and DevelopmentSetagaya-kuTokyoJapan

α-Synucleinopathies are a subgroup of neurodegenerative diseases including dementia with Lewy bodies(DLB)and Parkinson’s disease(PD).Pathologically,these disorders can be characterized by the presence of intraneuronal aggregates composed mainly of α-synuclein(αSyn),which are called Lewy bodies and Lewy *** report showed that more than 90% of αSyn aggregates are present in the form of very small deposits in presynaptic terminals of the affected neurons in ***,the mechanisms responsible for presynaptic accumulation of abnormal αSyn remain *** this article,we review recent findings on the involvement of presynaptic dysfunction in the initiation of neuronal dysfunctional *** review highlights that the presynaptic failure can be a potential trigger of the dying-back neuronal death in neurodegenerative diseases.

关键词： degenerative dysfunction involvement

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马来西亚马来学生华文习得研究——以尊孔国民型华文中学中三及中五马来学生为例

马来西亚马来学生华文习得研究——以尊孔国民型华文中学中三及中...

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作者：黄伟聪（wong Wooi choong）华中师范大学

学位级别：硕士

马来西亚是一个实行多元教育的国家,每个国民都有权利选择自己喜欢的教育源流。华文教育是马来西亚多元教育源流的一环。随着华文教育在全球日益受重视及在中国国家主席习近平提倡“一带一路”的大力推动下,华文的经济价值日益提升。有... 详细信息

马来西亚是一个实行多元教育的国家,每个国民都有权利选择自己喜欢的教育源流。华文教育是马来西亚多元教育源流的一环。随着华文教育在全球日益受重视及在中国国家主席习近平提倡“一带一路”的大力推动下,华文的经济价值日益提升。有鉴于此,马来西亚的华文教育也渐渐地受到各民族的关注,更吸引了许多马来家长把孩子送到华校就读,让孩子在一个华文氛围浓厚的华文小学(华小)或是国民型华文中学(华中)学习华文。目前,马来西亚共有1298所华小及80所华中。近年来,越来越多马来家长认同华小和华中的办校理念及办学方针。他们希望自己的孩子能在这样的学校学习华文、掌握华文。孩子毕业后能多掌握一种语言,对孩子们日后的升学或进入职场多了一份优势。在华中学习华文的马来学生人数逐年增加,他们一心想学好华文,很多时候却因为种种内在和外在的因素造成事与愿违。这些马来学生长达11年的时间处在一个华文作为第一语言教学或是华文作为母语教育的模式下学习华文。在这样的学习环境下,他们不但不能更好地掌握华文,反而因为语言差异和文化差异导致华文成绩每况愈下,甚至对华文产生厌倦和抗拒。笔者调查了尊孔华中的43位中三及中五的马来学生的华文学习现状、年中和年终华文课程测试的成绩及10位尊孔华中华文教师的反馈,进行深入的探讨与研究,希望能找出目前在尊孔华中马来学生在学习华文时存在的问题,并针对相关的问题进行分析及提出相应的建议和对策,希望本文能为在笔者执教的学校或其他华中就读的马来学生改善他们对华文的学习态度及提升他们学习华文的效率,让马来学生在华中学习华文的路上提供一定的借鉴。本文对基于课程测试的尊孔华中马来学生的华文习得研究共分为五章。第一章的具体内容是研究现状与选题的缘由。这部分的内容主要包括了研究现状、选题缘由、研究对象、研究内容、研究目的及研究方法。第二章的主要内容是针对43位研究对象在年中和年终华文课程测试的成绩分析。第三章的主要内容则是侧重对这群马来学生学习华文的情况的问卷调查及尊孔华中10位华文教师的反馈进行分析。第四章的内容是着重在问卷的分析结果,梳理出这43名马来学生在学习华文课程测试成绩欠佳的内在和外在的因素,在本章节里,同时也提出提高马来学生华文习得质量的建议。第五章是结语部分,对整篇论文进行总结,同时也在这章节里提出本论文不足的地方,并定下对将来的研究计划。最后,希望本论文能做到抛砖引玉的作用。通过这份不足的研究,让更多学者关心在华中就读的马来学生的华文学习情况,能为他们做出更多、更好及更全面的研究,让更多的马来学生能在华中学习华文的过程中交出一张亮眼的成绩,更让华中成为马来西亚马来学生学习华文的首选。

关键词：马来学生课程测试表现分析原因及对策

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