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我国上市公司财务危机的判断与预警

商业经济与管理 2009年第4期 90-96页

作者：李腊生张岩天津财经大学统计学院天津300222

准确识别与判断上市公司财务危机对于投资者具有特殊重要的意义,本文以相关财务理论为依据,将因子分析与选择性模型相结合,利用我国上市公司的实际数据,通过对比分析筛选出对财务危机有显著影响的财务变量,构建了判别上市公司财务危机... 详细信息

准确识别与判断上市公司财务危机对于投资者具有特殊重要的意义,本文以相关财务理论为依据,将因子分析与选择性模型相结合,利用我国上市公司的实际数据,通过对比分析筛选出对财务危机有显著影响的财务变量,构建了判别上市公司财务危机的因子分析Logit模型。以此为基础,本文进一步引入非财务变量,提出了判别上市公司财务危机的改进模型,并依据该模型讨论了上市公司财务危机的预警问题及数量界面。

关键词：财务危机因子分析 Logit模型准确率

living/controlled polymerization of vinylpyridines into sequence-regulated copolymers by Lewis pair

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Science China Chemistry 2024年第8期67卷 2737-2746页

作者： Qiankun Ding Wuchao Zhao Fukuan li Jianghua He Yuetao Zhang Department of State Key laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China

The poly(vinylpyridine)(PVP) based(co)polymers are of particular interest in materials science, due to their multifunctionality and diverse applications. So far, there is no report on the sequence-regulated copolymerization of vinylpyridines(VPs) and methacrylate monomer in one-step manner yet. Here we designed and synthesized a series of guanidine phosphines as Lewis base(LB), which is combined with bulky organoaluminium to construct Lewis pairs(LPs) for polymerization of VPs. The living/controlled polymerization of 4-vinylpyridine(4-VP) or 2-vinylpyridine(2-VP) can be accomplished with remarkable efficiency by such Lewis pair polymerization(LPP), furnishing polymers with high molecular weight(up to 288 kg/mol) and narrow molecular weight distribution(as low as 1.17). Mechanistic studies reveal the interaction of LPs and formation of zwitterionic intermediates, providing solid evidences to support the proposed polymerization mechanism. More importantly, by simply adjusting the la dosage, this LPP strategy realizes the unprecedented control over the sequence regulation of 2-VP-based copolymers from gradient to block in one-step manner, regardless of the monomer ratio, which greatly expands the versatility of the LPP.

关键词： guanidine phosphine Lewis pair polymerization living/controlled polymerization vinyl pyridine sequence regulation

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一种基于博弈论模型的Ad Hoc网络功率控制算法

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计算机学报 2009年第1期32卷 169-176页

作者：孙强李腊元陈年生上海电机学院上海200240 武汉理工大学计算机学院武汉430063 湖北师范学院计算机科学系湖北黄石435002

在Ad hoc网络中,采用控制数据报文向相邻节点的发射功率的方法来提高能量的使用效率是一种常用的方法,但是采用功率控制也会对网络连通性、延迟和容量带了负面影响.文中对Ad hoc网络中能量控制机制进行了讨论,给出了Ad hoc网络基于非合... 详细信息

在Ad hoc网络中,采用控制数据报文向相邻节点的发射功率的方法来提高能量的使用效率是一种常用的方法,但是采用功率控制也会对网络连通性、延迟和容量带了负面影响.文中对Ad hoc网络中能量控制机制进行了讨论,给出了Ad hoc网络基于非合作博弈的功率控制问题模型.提出了一种以满足网络连通性、容量最大化、网络半径最小为目标的分布式非合作功率控制博弈算法,并给出了对该算法纳什均衡的存在性和唯一性的证明.实验表明该算法具有较好的综合性能.

关键词： Ad hoc网络功率控制容量博弈纳什均衡

Management of locally advanced non-small cell lung cancer: State of the art and future directions

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Cancer Communications 2024年第1期44卷 23-46页

作者： Da Miao Jing Zhao Ying Han Jiaqi Zhou Xiuzhen li Ting Zhang Wen li Yang Xia Key laboratory of Respiratory Disease of Zhejiang Province Department of Respiratory and Critical Care MedicineSecond Affiliated Hospital of Zhejiang University School of MedicineHangzhouZhejiangP.R.China Department of Oncology Shaoxing Second HospitalShaoxingZhejiangP.R.China Department of Medical Oncology Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouZhejiangP.R.China Department of Chemoradiotherapy The Affiliated People’s Hospital of Ningbo UniversityNingboZhejiangP.R.China Key Discipline of Jiaxing Respiratory Medicine Construction Project Jiaxing Key Laboratory of Precision Treatment for Lung CancerAffiliated Hospital of Jiaxing UniversityJiaxingZhejiangP.R.China Department of Pathology Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouZhejiangP.R.China Department of Radiation Oncology Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouZhejiangP.R.China Cancer Center Zhejiang UniversityHangzhouZhejiangP.R.China

Lung cancer is the second most common and the deadliest type of cancer ***,non-small cell lung cancer(NSCLC)is the most com-mon pathological type of lung cancer;approximately one-third of affected patients have locally advanced NSCLC(la-NSCLC,stage III NSCLC)at *** of its heterogeneity,la-NSCLC often requires multidisciplinary ***,the prognosis of affected patients is much below satisfac-tion,and the efficacy of traditional therapeutic strategies has reached a *** the emergence of targeted therapies and immunotherapies,as well as the continuous development of novel radiotherapies,we have entered an era of novel treatment paradigm for ***,we reviewed the landscape of relevant therapeutic modalities,including adjuvant,neoadjuvant,and periop-erative targeted and immune strategies in patients with resectable la-NSCLC with/without oncogenic alterations;as well as novel combinations of chemora-diation and immunotherapy/targeted therapy in unresectable *** addressed the unresolved challenges that remain in the field,and examined future directions to optimize clinical management and increase the cure rate of la-NSCLC.

关键词： locally advanced non-small cell lung cancer neoadjuvant therapy adjuvant therapy immunotherapy targeted therapy

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基于LEACH协议的能耗均衡路由算法

计算机工程 2011年第7期37卷 91-93,111页

作者：张浩李腊元武汉理工大学计算机科学与技术学院武汉430063

分析LEACH协议,指出其在簇头选择、簇头与基站通信方面存在的不足。针对上述问题,以均衡能耗和节省能量为出发点,结合LEACH-C的特点及Dijkstra算法对LEACH协议进行改进,提出LEACH-EB协议。仿真结果表明,LEACH-EB协议能有效节省能量,均... 详细信息

分析LEACH协议,指出其在簇头选择、簇头与基站通信方面存在的不足。针对上述问题,以均衡能耗和节省能量为出发点,结合LEACH-C的特点及Dijkstra算法对LEACH协议进行改进,提出LEACH-EB协议。仿真结果表明,LEACH-EB协议能有效节省能量,均衡能量消耗,延长网络生命周期。

关键词：无线传感器网络 LEACH协议能耗均衡簇头选择簇间路由

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高等教育非货币化收益与溢出效益的实证分析

清华大学教育研究 2011年第1期32卷 89-93页

作者：李锋亮李拉清华大学教育研究院北京100084 首都师范大学政法学院北京100089

发达国家的许多研究都证实了人力资本的非货币化收益和溢出效益,但是中国相关的实证研究非常少。本文将丰富该领域中国实证研究的匮乏,通过对那些随自己子女迁移到北京居住生活的老年人调查获得数据。实证结果发现,教育能够带来显著的... 详细信息

发达国家的许多研究都证实了人力资本的非货币化收益和溢出效益,但是中国相关的实证研究非常少。本文将丰富该领域中国实证研究的匮乏,通过对那些随自己子女迁移到北京居住生活的老年人调查获得数据。实证结果发现,教育能够带来显著的非货币化收益与家庭成员的溢出效益。

关键词：高等教育非货币化收益溢出效益迁移

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一种支持多QoS约束的多播路由协议

小型微型计算机系统 2005年第12期26卷 2065-2068页

作者：许毅李腊元武汉理工大学现代教育技术中心计算机科学与技术学院武汉430063

在分析YAM、QoSMIC和QMRP协议的基础上,讨论了包括延时、延时抖动、带宽和代价约束的多播路由问题,描述了一种适用于多QoS约束的多播路由的网络优化模型,提出了一种支持多QoS约束的多播路由协议(MRPMQoS),构建在NS2下该协议的仿真模块.... 详细信息

在分析YAM、QoSMIC和QMRP协议的基础上,讨论了包括延时、延时抖动、带宽和代价约束的多播路由问题,描述了一种适用于多QoS约束的多播路由的网络优化模型,提出了一种支持多QoS约束的多播路由协议(MRPMQoS),构建在NS2下该协议的仿真模块.该协议只要求网络链路(或节点)的局部状态信息,不需要维护全局状态信息,多播组成员可动态地加入/退出多播会晤.该协议采用单路径寻径和多路径寻径相结合的搜索方式,有效地减少构造一棵多播树的开销,降低结点加入延时和提高寻径成功率.NS2仿真结果证明,该协议的可用性和有效性,可用于不同规模网络,具有良好的可扩展性.

关键词：多播路由多QoS约束 MRPMQoS 网络

Sedimentary Environment and Mineralization of the Black Shale Polymetallic layer in the Early Cambrian,SW China:Constraints from in situ la-ICP-MS Analysis of Pyrite

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 416-429页

作者： YANG Zhen FU Yong li Chao CAI Xi GUO Chuan College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China Key laboratory of Karst Georesources and the Environment Ministry of EducationGuizhou UniversityGuiyang 500025China National Research Center for Geoanalysis Chinese Academy of Geological SciencesBeijing 100037China

A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou *** mineral that makes up the polymetallic layer is related to the sedimentary *** analyze the differentiation mechanism between polymetallic deposits(Ni-Mo and V),the Zhijin Gezhongwu profile located in the outer shelf and the Sansui Haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of *** results show that δ^(34)S values of pyrite vary widely from−7.8‰to 28‰in the Gezhongwu profile,while the δ^(34)S values are relatively uniform(from 27.8‰to 38.4‰)in the Haishan *** isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive Yangtze platform;this indicates that the δ^(34)SO_(4)^(2−)values in seawater must be differently distributed in depositional *** sulfur in the Ni-Mo layer is produced after the mixing of seawater and hydrothermal fluid,while the V layer mainly originates from ***,the Ni-Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid.

关键词： sedimentary environment black shale polymetallic layer pyrite early Cambrian

SS-laSS Zircon Dating Deciphering Multiple Episodes of Anatexis in a Deeply-Subducted Continental Crust:An Example from Sulu Orogen,China

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Journal of Earth Science 2024年第1期35卷 85-98页

作者： Peng Feng Lu Wang Xiawen li Wenjie Ding Zhe Chen School of Resource&Environment and Safety Engineering University of South ChinaHengyang 421001China State Key laboratory of Geological Processes and Mineral Resources Center for Global TectonicsSchool of Earth SciencesChina University of GeosciencesWuhan 430074China No.8 Institute of Geology and Mineral Resources Exploration of Shandong Province Rizhao 276826China

‘Single shot'laser-ablation split-stream(SS-laSS)technique analyzing unpolished zircon grains makes their thin rims tenable for determination,which thus offers great potential in deciphering the timing of multiple and short-lived episodes of anatexis and metamorphism in deeplysubducted continental *** granitic gneisses in the deeply subducted continental crust undergoing considerable fluid-melt activities persist multistage growth of ***,a comparative study of SS-laSS and laser ablation inductively coupled plasma mass spectrometer(la-ICP-MS)zircon dating was conducted on the granitic gneisses from the Sulu belt in this *** mostly show a core-mantle-rim structure with CL-bright rims thinner than 5μ*** la-ICP-MS dating,relict magmatic zircon cores yield protolith ages of ca.756-747 Ma;whereas the dark mantles record synexhumation anatexis at ca.214 *** contrast,according to the U-Pb dates,trace element features,zircon crystallization temperatures and geological context,SS-laSS zircon petrochronology deciphers three episodes of anatectic events,as follows:(i)the first episode of anatexis at ca.218-217 Ma dominated by phengite-breakdown melting,likely facilitating the exhumation of the UHP slice from mantle depth;(ii)the second episode of anatexis at ca.193–191 Ma indicating part of northern Dabie-Sulu belt was still“hot”because of buried in the thickened orogenic crust at that time;(iii)the third episode of anatexis(ca.162–161 Ma)consistent with the intrusion ages(ca.161–141 Ma)of the Jurassic to Cretaceous granitoids in this orogen,suggesting the initial collapse of the orogenic root of the Sulu belt occurred at late Jurassic due to the Izanagi plate initially subducting beneath the margin of Eastern *** study sheds new light upon the utilization of SS-laSS petrochronology deciphering multiple anatectic events in the deeply-subducted continental crust and supports us in better understanding the tectonic evolution of Dabie-

关键词： anatexis laser ablation laser-ablation split-stream ultrahigh-pressure metamorphic belt Sulu Orogen