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A load balancing multi-path routing scheme based on effective voids for optical burst switching networks

Science China(Information Sciences) 2015年第2期58卷 131-139页

作者： HUANG sheng zhang YunShui SUN Li Qin YANG Xiaolong long KePing Key Laboratory of Optical Fiber Communication Technology Chongqing University of Posts and Telecommunications

Multi-path routing in the optical burst switching(OBS) networks can reduce the burst loss probability(BLP) by distributing the data burst traffic to multiple paths, compared with single path routing. Unlike the other multi-path routing schemes without considering the carrying capability of the routes, a new multi-path routing scheme based on effective voids(MPEV) is proposed to balance the load of multi-path and reduce the BLP in the paper. MPEV scheme first obtains the information on effective voids of the bottleneck link of multipath by sending a probe packet periodically. The effective voids can accommodate data bursts and accurately represent the available channel resource that is the main determinant of the BLP for OBS networks without optical random access memory. Then MPEV scheme distributes the burst traffic between an ingress node and an egress node to multiple link-disjoint paths by the ratio of the effective voids. More traffic is distributed to the path that has more effective voids, and vice versa. And the distributed amount is proportional to the effective voids of the bottleneck link. So MPEV scheme can balance the load of multi-path routes and can effectively reduce the BLP by avoiding the high load of a single path. And it is easy to implement and agilely adapt to dynamic network traffic. The performance of MPEV scheme is analyzed by queuing theory and is evaluated by simulation. The numerical results show that the proposed scheme can effectively reduce the BLP and balance the traffic load over multiple paths at the same time.

关键词： optical burst switching multi-path routing effective voids bottleneck link balance traffic load

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微量Cr对Cu-Zn合金组织和性能的影响

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有色金属加工 2006年第5期35卷 15-17页

作者：邓楚平黄伯云尹志民张生龙中南大学湖南长沙410083

本文采用扫描金相-微区成分分析和 X 射线衍射物相分析方法,对 Cu-Zn-Cr 合金的组织结构进行了观察和分析,并测定了经过不同时效工艺处理后合金的拉伸力学性能和电学性能。研究结果表明:该合金经在线水淬+45%预冷变形+450℃时效4 h 后,... 详细信息

本文采用扫描金相-微区成分分析和 X 射线衍射物相分析方法,对 Cu-Zn-Cr 合金的组织结构进行了观察和分析,并测定了经过不同时效工艺处理后合金的拉伸力学性能和电学性能。研究结果表明:该合金经在线水淬+45%预冷变形+450℃时效4 h 后,其抗拉强度、屈服强度和延伸率分别达到482 MPa、388 MPa和23.6%,相对电导率则达到78.2%IACS。显微组织结构分析结果表明,时效态合金的力学性能由回复-再结晶软化和时效析出强化二个过程控制,合金的高强度主要源于预冷变形引起的亚结构强化和 Cr 粒子的析出强化。

关键词：微量Cr Cu—Zn合金形变热处理组织性能

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Certifying the Global Optimality of Quartic Minimization over the Sphere

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Journal of the Operations Research Society of China 2022年第2期10卷 241-287页

作者： sheng-long Hu Department of Mathematics School of ScienceHangzhou Dianzi UniversityHangzhou 310018ZhejiangChina

The quartic minimization over the sphere is an NP-hard problem in the general *** exist various methods for computing an approximate solution for any given *** practice,it is quite often that a global optimal solution was found but without a *** will present in this article two classes of methods which are able to certify the global optimality,i.e.,algebraic methods and semidefinite program(SDP)relaxation *** advances on these topics are summarized,accompanied with some emerged new *** want to emphasize that for mediumor large-scaled instances,the problem is still a challenging one,due to an apparent limitation on the current force for solving SDP problems and the intrinsic one on the approximation techniques for the problem.

关键词： Quartic minimization Tensor Sphere Global optimality Elimination method Critical points Eigenvectors Determinant Nondegenerate Characteristic polynomial SDP relaxations Moment matrix Flatness Positivstellensatz Nonnegative polynomial Sums of squares Duality

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Lanthanide-oxo clusters for efficient catalytic reduction of carboxamides

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Science China Chemistry 2023年第2期66卷 443-448页

作者： Zhen-zhang Weng Chao-long Chen long-Wu Ye La-sheng long Lan-Sun Zheng Xiang-Jian Kong Collaborative Innovation Center of Chemistry for Energy Materials State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China

The reduction of carboxamides into high value-added amines is a very interesting but great challenging *** we demonstrate that polynuclear lanthanide-oxo clusters Ln16(Ln=Eu and Gd)can be used as efficient catalyst to reduce primary and secondary carboxamides to amines with excellent yield of 71%-98%and broad substrates *** methodology can extend to the gram-scale synthesis of phenethylamine drug with 93%*** on the isolation and characterization of catalytic intermediates,a catalytic mechanism involving multipath reaction is *** work provides efficient lanthanide cluster catalysts for the reduction of carboxamides to amines.

关键词： lanthanide clusters amide reduction metal-hydride BH3 catalytic mechanism

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The Security of Using Large Language Models:A Survey With Emphasis on ChatGPT

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 1-26页

作者： Wei Zhou Xiaogang Zhu Qing-long Han Lin Li Xiao Chen sheng Wen Yang Xiang the School of Science Computing and Engineering Technologies Swinburne University of Technology IEEE the School of Computer and Mathematical Sciences the University of Adelaide Adelaide the Faculty of Science and Engineering Southern Cross University the School of Information and Physical Sciences the University of Newcastle

ChatGPT is a powerful artificial intelligence(AI)language model that has demonstrated significant improvements in various natural language processing(NLP) tasks. However, like any technology, it presents potential security risks that need to be carefully evaluated and addressed. In this survey, we provide an overview of the current state of research on security of using ChatGPT, with aspects of bias, disinformation, ethics, misuse,attacks and privacy. We review and discuss the literature on these topics and highlight open research questions and future *** this survey, we aim to contribute to the academic discourse on AI security, enriching the understanding of potential risks and mitigations. We anticipate that this survey will be valuable for various stakeholders involved in AI development and usage, including AI researchers, developers, policy makers, and end-users.

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腰方肌阻滞与腹横肌平面阻滞应用于妇科腹腔镜术后镇痛效果的比较

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河北医科大学学报 2020年第12期41卷 1450-1454页

作者：张隆盛卢燕张楷弘杨铎叶淑君黄志良广东省揭阳市人民医院麻醉科广东揭阳522000 广东医科大学附属医院麻醉科广东湛江524000 右江民族医学院研究生学院广西百色533000

目的分析腰方肌阻滞(quadratus lumborum block,QLB)与腹横肌平面阻滞(transversus abdominis plane block,TAP)应用于妇科腹腔镜术后镇痛的效果。方法选取择期行腹腔镜卵巢瘤切除术患者50例分为2组,QLB组和TAP组各25例。两组均采用气... 详细信息

目的分析腰方肌阻滞(quadratus lumborum block,QLB)与腹横肌平面阻滞(transversus abdominis plane block,TAP)应用于妇科腹腔镜术后镇痛的效果。方法选取择期行腹腔镜卵巢瘤切除术患者50例分为2组,QLB组和TAP组各25例。两组均采用气管插管全凭静脉麻醉,在麻醉诱导前,QLB组行双侧QLB,TAP组行双侧TAP,术后均采用静脉自控镇痛。比较术后2,6,12,24,48 h患者静息疼痛视觉模拟评分法(visual analogue scale,VAS)评分;比较术后首次按压镇痛泵时间、48 h内镇痛泵有效按压次数、舒芬太尼使用总量和氟比洛芬酯补救性镇痛例数;比较术后48 h不良反应发生情况。结果2组各时点静息疼痛VAS评分呈先逐渐上升随后再下降趋势,术后24 h疼痛最严重,且QLB组低于TAP组,组间、时点间、组间·时点间交互作用差异均有统计学意义(P<0.05)。与TAP组比较,QLB组首次按压镇痛泵时间明显延长(P<0.05),48 h内镇痛泵有效按压次数、舒芬太尼使用总量和氟比洛芬酯补救镇痛例数明显降低(P<0.05),QLB组术后48 h不良反应发生率明显降低(P<0.05)。结论与TAP比较,QLB镇痛效果更加完善,作用时间更长并减少术后阿片类药物应用,更适合应用于妇科腹腔镜术后多模式镇痛。

关键词：卵巢肿瘤腹腔镜腰方肌阻滞腹横肌平面阻滞

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胸腔镜肺大疱切除手术的麻醉策略:超声引导菱形肌-肋间肌-低位前锯肌平面阻滞联合全身麻醉

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河北医科大学学报 2021年第11期42卷 1312-1316页

作者：张隆盛张楷弘杨铎韦武芝张欢楷何俊冰广东省揭阳市人民医院麻醉科广东揭阳522000 右江民族医学院研究生学院广西百色533000 广东省揭阳市人民医院心胸外科广东揭阳522000 广东省揭阳市人民医院临床医学科研实验室广东揭阳522000

目的评价超声引导菱形肌-肋间肌-低位前锯肌平面阻滞联合全身麻醉用于胸腔镜肺大疱切除手术患者的麻醉镇痛效果。方法选取择期行胸腔镜肺大疱切除手术患者70例,性别不限,年龄18~60岁,美国麻醉医师协会分级(American Society of Anesthes... 详细信息

目的评价超声引导菱形肌-肋间肌-低位前锯肌平面阻滞联合全身麻醉用于胸腔镜肺大疱切除手术患者的麻醉镇痛效果。方法选取择期行胸腔镜肺大疱切除手术患者70例,性别不限,年龄18~60岁,美国麻醉医师协会分级(American Society of Anesthesiologists,ASA)分级Ⅰ或Ⅱ级,随机分为阻滞联合全身麻醉组(R组)和单纯全身麻醉组(G组),每组35例。R组在麻醉诱导前实施患侧菱形肌-肋间肌-低位前锯肌平面阻滞(rhomboid intercostal and subserratus plane block,RISS),G组不进行干预。2组均采用双腔支气管插管静脉全身麻醉,术后行静脉自控镇痛(patient controlled intravenous analgesia,PCIA)。记录术后2,6,12,24,48 h静止和咳嗽视觉疼痛模拟评分(visual analogue scale,VAS)评分;记录术中丙泊酚、瑞芬太尼使用总量;记录术后48 h内镇痛泵按压次数、舒芬太尼使用总量、氟比洛芬酯补救性镇痛例数、镇痛满意度评分;记录术后48 h内镇痛期间不良反应发生情况,包括皮肤瘙痒、恶心呕吐、眩晕等。结果2组术后各时间点静息和咳嗽疼痛VAS评分均呈逐渐升高再降低趋势,且R组升高幅度明显小于G组,组间、时点间、组间·时点间交互作用差异均有统计学意义(P<0.05),R组术中丙泊酚、瑞芬太尼使用总量明显低于G组(P<0.05),R组术后48 h镇痛按压次数、舒芬太尼使用总量、氟比洛芬酯镇痛例数明显低于G组(P<0.05),镇痛满意度评分明显高于G组(P<0.05)。结论超声引导菱形肌-肋间肌-低位前锯肌平面阻滞联合全身麻醉用于胸腔镜肺大疱切除手术可为患者提供良好术后镇痛,减少围术期镇静镇痛药物应用,提高镇痛满意度。

关键词：气胸胸腔镜肺大疱切除手术菱形肌-肋间肌-低位前锯肌平面阻滞

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Screening and Analysis of Proteins Interacting with TaPDK from Physiological Male Sterility Induced by CHA in Wheat

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Journal of Integrative Agriculture 2013年第6期12卷 941-950页

作者： zhang long-yu zhang Gai-sheng ZHAO Xin-liang YANG Shu-ling College of Agronomy Northwest A&F University/Wheat Breeding Engineering Research Center Ministry of Education/Key Laboratory of Crop Heterosis of Shaanxi Province

To further research the regulatory network of pyruvate dehydrogenase kinase （designated as TaPDK） in physiological male-sterility （PHYMS） of wheat induced by chemical hybridizing agent （CHA） SQ-1, an anther cDNA library was constructed, and the proteins interacting with TaPDK were screened via yeast two-hybrid technique. Subsequently, a few candidate proteins in nucleotide expression levels were detected by real-time quantitative PCR. Yeast-two hybrid screening was performed by mating yeast strain Y2HGold containing BD-TaPDK bait plasmid with yeast strain Y187 including anther cDNA library plasmid. Diploid yeast cells were plated on synthetic dropout nutrient medium （SD/-Ade/-His/-Leu/-Trp）（QDO）, and further were incubated on QDO medium containing AbA and X-α-Gal. The interactions between TaPDK and the proteins obtained from positive colonies were further confirmed by co-transformation validation. After plasmids DNA were extracted from blue colonies and sequenced, the sequences results were analyzed by bioinformatic methods. Finally, 24 colonies were obtained, including eight genes, namely non-specific lipid-transfer protein precursor （TanLTP）, polyubiquitin （TaPUbi）, glyceraldehyde-3-phosphate dehydrogenase, proliferating cell nuclear antigen （TaPCNA）, CBS domain containing protein （TaCBS）, actin, guanine nucleotide-binding protein beta subunit, chalcone synthase, and three new genes with unknown function. The results of quantitative RT-PCR showed that the expression levels of TanLTP, TaPUbi, and TaPCNA were obviously up-regulated in PHYMS anther, and TaCBS expression was only increased at the tricellular stage in PHYMS anther compared with in fertile lines. Whereas, the expression of TaPDK was obviously down-regulated in PHYMS lines. Collectively, these datas indicated that the majority of candidate proteins might be related to pollen abortion in PHYMS lines, which further suggested that TaPDK plays multiple roles in pollen development, besides participating in r

关键词： wheat (Triticum aestivum L.) chemical hybridizing agent pyruvate dehydrogenase kinase yeast two-hybrid pollen abortion

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Synergistically enhanced ORR and HER performance on Co-N-C coupled in-situ generated PtCo intermetallic

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Journal of Energy Chemistry 2025年第1期100卷 721-729页

作者： Guanyu Luo Min Song Lulu An Xiao Huang Qian zhang Chenhao zhang Tao Shen Shuang Wang Deli Wang Key Laboratory of Material Chemistry for Energy Conversion and Storage (Huazhong University of Science and Technology) Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Integrating multi-scale sites in a composite catalyst is vital to realize efficient ***,a synergistic composite catalyst consisting of Co atomic sites and in-situ generated PtCo intermetallic compounds （IMCs）(o-PtCo@CoNC) is proposed through Co pre-anchoring and subsequent impregnation-reduction *** loading of Co atoms provides a chance for in-situ generating PtCo ordered intermetallic *** remaining Co single atoms and PtCo IMCs construct synergistic electrocatalytic *** from the ordered structure,synergistic effect of Pt Co IMCs and Co single atoms,o-PtCo@CoNC exhibits excellent electrocatalytic performance for oxygen reduction reaction （ORR） and hydrogen evolution reaction （HER） with mass activity of 1.21 A mgPt-1（at 0.9 V） and5.70 A mgPt-1（at an overpotential of 100 mV）,***,o-PtCo@CoNC delivers negligible loss of half-wave potential and overpotential during long-term stability test in acid solutions,with 13 mV decay after 50,000 potential cycles for ORR and a 2.7 mV decay after 20,000 potential cycles for *** integration strategy of single-atomic sites coupled IMCs paves the way for enhancing the activity and durability of Pt-based electrocatalysts.

关键词： Electrolytic reduction

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PRECEDE-PROCEED模式在社区慢性病健康管理中应用的研究进展

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中国健康教育 2017年第8期33卷 731-734,740页

作者：付晶崔华欠夏瑶张龙生邝玉敏周光清李海燕南方医科大学卫生管理学院广东广州510515 广州市天河区车陂街卫生服务中心广东广州510515 南方医科大学南方医院健康管理中心广东广州510515 南方医科大学研究生学院广东广州510515

我国正处于慢性病高负担期,且具有"患病人数多、医疗成本高、患病时间长、服务需求大"的特点。慢性病综合防控工作力度虽然逐步加大,但防控形势依然严峻,传统的社区公共卫生服务已无法满足社区慢性病患者日益多层次和多样化的健康需求... 详细信息

我国正处于慢性病高负担期,且具有"患病人数多、医疗成本高、患病时间长、服务需求大"的特点。慢性病综合防控工作力度虽然逐步加大,但防控形势依然严峻,传统的社区公共卫生服务已无法满足社区慢性病患者日益多层次和多样化的健康需求。本文通过文献调查法对PRECEDE-PROCEED模式的理论框架和国内外现状进行阐述,探讨目前PRECEDE-PROCEED模式在社区慢性病健康管理中应用的研究进展,分别从政策导向、社会需求、理论支撑和技术支持4方面进行可行性分析,并提出不足之处和建议,为创新和优化社区慢性病健康管理模式提供参考和借鉴。

关键词： PRECEDE-PROCEED模式慢性病社区健康管理

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