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Resource allocation based on genetic algorithm for multi-hop OFDM system with non-regenerative relaying

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The Journal of china Universities of Posts and Telecommunications 2009年第5期16卷 25-32页

作者： SHI Jie , XU wen-jun, HE Zhi-qiang, NIU Kai, WU Wei-ling School of Information and Telecommunication Engineering, beijing University of Posts and Telecommunications, beijing 100876, china School of Information and Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This article investigates resource allocation in multi-hop orthogonal frequency division multiplexing （OFDM） system with amplifying-and-forwarding relaying to maximize the end-to-end capacity, Most existing methods for multi-hop system focus on power allocation or subcarrier selection separately, but joint resource allocation is rarely considered due to the absence of effective interaction schemes. In this work, a novel joint resource allocation methodology is proposed based on Partheno genetic algorithm （PGA）, which produces excellent subcarrier allocation set （referred to as individual in PGA） with higher capacity by evolution operator generation by generation. In addition, an adaptive power allocation is also designed to evaluate the fitness of PGA and further enhance the system capacity. Both theoretical analysis and simulated results show the effectiveness of the proposed joint strategy. It outperforms the traditional method by as much as 40% capacity improvement for 3-hop relaying system when system power is high, and obtains much more capacity enhancement percent under conditions of low system power.

关键词： multi-hop OFDM system non-regenerative relaying genetic algorithm power allocation subcarrier selection resource allocation

差错责任追究制度下的股价同步性变动:警惕非预期的制度效应

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现代财经（天津财经大学学报） 2024年第8期 92-108页

作者：刘文军何茜福建农林大学经济与管理学院福建福州350002 中央财经大学会计学院北京100081

差错责任追究制度在公司内部治理中占据重要地位,然而其可能产生的非预期效应却常被忽视。基于股价同步性独特视角,利用2007-2022年间A股上市公司的数据,深入探讨了这一问题,并通过构建双重差分(DID)模型,精确分析了差错责任追究制度对... 详细信息

差错责任追究制度在公司内部治理中占据重要地位,然而其可能产生的非预期效应却常被忽视。基于股价同步性独特视角,利用2007-2022年间A股上市公司的数据,深入探讨了这一问题,并通过构建双重差分(DID)模型,精确分析了差错责任追究制度对股价同步性的影响。研究结果显示,实施该制度后,公司的股价同步性显著提升,尤其是在那些应计盈余管理减少但真实盈余管理增加,以及年报可读性降低的公司中,这一效应更为显著。进一步研究发现,管理层持股较少、分析师跟踪较少的公司,受该制度的影响更为明显。此外,股价同步性的提高导致了公司权益资本成本的增加和投资者信心的降低。研究揭示了差错责任追究制度可能引发管理层盈余管理和信息披露的策略性行为,从而降低股票定价效率。代理冲突和外部监督的缺失是诱导这些非预期效应的关键因素。研究结果不仅深化了对公司内部治理机制非预期效应的理解,而且为监管机构制定相关政策提供了重要的参考,以警惕并应对可能的非预期后果。

关键词：差错责任追究制度股价同步性盈余管理年报可读性

Disaster effects of climate change in High Mountain Asia:State of art and scientific challenges Disaster effects of climate change in High Mountain Asia:State of art and scientific challenges

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Advances in Climate Change Research 2024年第3期15卷 367-389页

作者： Hao WANG Bin-Bin WANG Peng CUI Yao-Ming MA Yan WANG Jian-Sheng HAO Yu WANG Ya-Mei LI Li-jun SUN Jiao WANG Guo-Tao ZHANG Wei-Mo LI Yu LEI wen-Qing ZHAO Jin-Bo TANG Chao-Yue LI Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China State Key Laboratory of Tibetan Plateau Earth system Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Institute of Geographic sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China china‒Pakistan Joint Research Center on Earth sciences Chinese Academy of SciencesIslamabad 45320Pakistan College of Earth and Planetary sciences University of Chinese Academy of SciencesBeijing 100049China College of Atmospheric Science Lanzhou UniversityLanzhou 730000China National Observation and Research Station for Qomolongma Special Atmospheric Processes and Environmental Changes Dingri 858200China

High Mountain Asia(HMA)shows a remarkable warming tendency and divergent trend of regional precipitation with enhanced meteorological *** rapid thawing of the HMA cryosphere may alter the magnitude and frequency of nature *** reviewed the influence of climate change on various types of nature hazards in HMA region,including their phenomena,mechanisms and *** reveals that:1)the occurrences of extreme rainfall,heavy snowfall,and drifting snow hazards are escalating;accelerated ice and snow melting have advanced the onset and increased the magnitude of snowmelt floods;2)due to elevating trigger factors,such as glacier debuttressing and the rapid shift of thermal and hydrological regime of bedrock/snow/ice interface or subsurface,the mass flow hazards including bedrock landslide,snow avalanche,ice-rock avalanches or glacier detachment,and debris flow will become more severe;3)increased active-layer detachment and retrogressive thaw slumps slope failures,thaw settlement and thermokarst lake will damage many important engineering structures and infrastructure in permafrost region;4)multi-hazards cascading hazard in HMA,such as the glacial lake outburst flood(GLOF)and avalanche-induced mass flow may greatly enlarge the destructive power of the primary hazard by amplifying its volume,mobility,and impact force;and 5)enhanced slope instability and sediment supply in the highland areas could impose remote catastrophic impacts upon lowland regions,and threat hydropower security and future water *** future,ongoing thawing of HMA will profoundly weaken the multiple-phase material of bedrock,ice,water,and soil,and enhance activities of nature *** and cascading hazards of high magnitude will prevail in *** the glacier runoff overpasses the peak water,low flow or droughts in lowland areas downstream of glacierized mountain regions will became more frequent and *** escalating hazards in the HMA region requires tackling s

关键词： High Mountain Asia Climate change Cryosphere degradation Nature hazards Disaster risk

The construction of infinite families of any k-tight optimal and singular k-tight optimal directed double loop networks

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Science china mathematics 2007年第7期50卷 1055-1064页

作者： Bao-xing CHEN~(1+) Xie-bin CHEN~2 Ji-xiang MENG~3 wen-jun XIAO~4 1 Department of Computer Science,Zhangzhou Teachers College,Zhangzhou 363000,china 2 Department of mathematics and Information Science,Zhangzhou Teachers College,Zhangzhou 363000,china 3 College of mathematics & system Science,Xinjiang University,Urumqi 830046,china 4 Department of Computer Science,South china University of Technology,Guangzhou 510641,china Department of Computer Science Zhangzhou Teachers College Zhangzhou China Department of mathematics and Information Science Zhangzhou Teachers College Zhangzhou China College of mathematics & system Science Xinjiang University Urumqi China Department of Computer Science South China University of Technology Guangzhou China

The double loop network(DLN)is a circulant digraph with n nodes and outdegree *** is an important topological structure of computer interconnection networks and has been widely used in the designing of local area networks and distributed *** the number n of nodes,how to construct a DLN which has minimum diameter?This problem has attracted great attention.A related and longtime unsolved problem is:for any given non-negative integer k,is there an infinite family of k-tight optimal DLN?In this paper,two main results are obtained:(1)for any k≥0,the infinite families of k-tight optimal DLN can be constructed,where the number n(k,e,c)of their nodes is a polynomial of degree 2 in e with integral coefficients containing a parameter c.(2)for any k≥0, an infinite family of singular k-tight optimal DLN can be constructed.

关键词： double loop network diameter k-tight optimal singular k-tight optimal 05C12 05C20 05C85

青藏高原低涡的活动特征和敏感区识别及其与陆面的关联分析研究

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高原气象 2024年第3期43卷 529-548页

作者：李世园吕少宁文军复旦大学大气与海洋科学系/大气科学研究院上海200438 成都信息工程大学大气科学学院/高原大气与环境四川省重点实验室四川成都610225

青藏高原低涡是夏季青藏高原边界层内产生的中尺度低压涡旋系统,对高原天气及其周边地区降水有重要影响。本文利用由客观识别法得到的高原低涡数据集以及ERA5-land再分析资料,通过相关分析、回归分析、贝叶斯时间序列分析算法和概率统... 详细信息

青藏高原低涡是夏季青藏高原边界层内产生的中尺度低压涡旋系统,对高原天气及其周边地区降水有重要影响。本文利用由客观识别法得到的高原低涡数据集以及ERA5-land再分析资料,通过相关分析、回归分析、贝叶斯时间序列分析算法和概率统计等方法,对1950-2021年高原低涡的活动特征进行了统计和分析,根据高原低涡的路径及强度划定了高原低涡活动的敏感区,并分析了不同陆面参量与高原低涡的联系。结果表明,高原低涡的年总个数和年总持续时间都呈显著增加趋势(置信度95%),气候倾向率分别为0.16个·a^(-1)和1.25 h·a^(-1);高原低涡活跃期(5-8月)总个数和总持续时间的增加趋势不显著;高原低涡活动的敏感区位于藏北高原北侧、可可西里山脉附近,与青藏高原中西部的主要山脉相对应;敏感区内的地表潜热、地表长波辐射以及地表0~7 cm土壤湿度与高原低涡个数和持续时间呈正相关,而地表感热与高原低涡个数和持续时间呈负相关;进一步发现当时间尺度为年际变化时,高原低涡与降水的变化相对一致,而在日尺度上,地表感热主要在敏感区及其以东地区与低涡个数、持续时间和强度呈正相关,其中以5月和6月最为显著。本研究中的结论为进一步分析高原低涡敏感区内的陆-气相互作用机理,以及高原低涡数值模拟和数据同化研究提供理论依据。

关键词：青藏高原高原低涡陆-气相互作用

Properties of Reactive Magnetron Sputtered ITO Films without in-situ Substrate Heating and Post-deposition Annealing

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Journal of Materials Science & Technology 2000年第3期16卷 281-285页

作者： Meng CHEN, Xuedong BAI, jun GONG, Chao SUN, Rongfang HUANG and Lishi wen (Institute of Metal Research, the Chinese Academy of sciences, Shenyang 110015, china) Ion Beam Lab. Shanghai Institute of Metallurgy Chinese Academy of Sciences Shanghai 200050 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

Indium tin oxide (ITO) films were prepared on polyester, Si and glass substrate with relatively high deposition rate of above 0.9 nm/s by DC reactive magnetron sputtering technique at the sputtering pressure of 0.06 Pa system, respectively. The dependence of resistivity on deposition parameters, such as deposition rate, target-to-substrate distance (TSD), oxygen flow rate and sputtering time (thickness), has been investigated, together with the structural and the optical properties. It was revealed that all ITO films exhibited lattice expansion. The resistivity of ITO thin films shows significant substrate effect: much lower resistivity and broader process window have been reproducibly achieved for the deposition of ITO films onto polyester rather than those prepared on both Si and glass substrates. The films with resistivity of as low as 4.23 x 10^-4 Ω.cm and average transmittance of ～78% at wavelength of 400～700 nm have been achieved for the films on polyester at room temperature.

关键词： ITO Properties of Reactive Magnetron Sputtered ITO Films without in-situ Substrate Heating and Post-deposition Annealing TSD rate than

基于仿真机理和改进回归决策树的二噁英排放建模

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自动化学报 2024年第8期50卷 1601-1619页

作者：夏恒汤健余文乔俊飞北京工业大学信息学部北京100124 北京工业大学智慧环保北京实验室北京100124 墨西哥国立理工大学高级研究中心(CINVESTAV-IPN) 墨西哥07360墨西哥

城市固废焚烧(Municipal solid waste incineration,MSWI)过程是“世纪之毒”二噁英(Dioxin,DXN)的重要排放源之一.截止目前为止,DXN的演化机理和实时检测仍是尚未解决的难题.现有研究主要基于离线化验数据构建数据驱动模型,DXN的检测... 详细信息

城市固废焚烧(Municipal solid waste incineration,MSWI)过程是“世纪之毒”二噁英(Dioxin,DXN)的重要排放源之一.截止目前为止,DXN的演化机理和实时检测仍是尚未解决的难题.现有研究主要基于离线化验数据构建数据驱动模型,DXN的检测未有效结合燃烧过程机理.针对该问题,本文提出基于仿真机理和改进线性回归决策树(Linear regression decision tree,LRDT)的DXN排放建模.首先,采用基于床层固废燃烧模拟软件FLIC(Fluid dynamic incinerator code)和过程工程先进系统软件(Advanced system for process engineering Plus,Aspen Plus)耦合的数值仿真模型,获取蕴含多运行工况的虚拟机理数据;接着,利用虚拟机理数据构建基于改进LRDT的CO_(2)、CO和O_(2)燃烧状态表征变量模型;然后,以真实CO_(2)、CO、O_(2)作为输入和以DXN真值作为输出,构建多入单出LRDT的过程映射模型(Process mapping model,PMM),再利用该模型进行半监督学习和结构迁移得到机理映射模型1(Mechanism mapping models1,MMM1);最后,通过结构增量学习获得基于半监督迁移学习的MMM2模型.在实验室的半实物平台和北京某MSWI厂的边侧验证平台对所提方法进行了工业应用验证.实验结果证明了所提方法与研发的软测量系统可有效实现二噁英排放浓度在线检测.

关键词：城市固废焚烧二噁英燃烧状态数值仿真机理线性回归决策树半监督迁移学习

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数字人民币发行对财务会计制度的影响研究

当代财经 2024年第2期 139-153页

作者：巫文勇李泽军江西财经大学法学院江西南昌330013

当前,数字人民币正在我国发行与流通,数字人民币应用场景正逐步扩大,其在支付中的比重呈快速增长态势。数字人民币发行与流通会对会计基本假设、会计基本职能、企业的信息质量和现有财务管理体系产生广泛而深刻的影响,并会对现有财务会... 详细信息

当前,数字人民币正在我国发行与流通,数字人民币应用场景正逐步扩大,其在支付中的比重呈快速增长态势。数字人民币发行与流通会对会计基本假设、会计基本职能、企业的信息质量和现有财务管理体系产生广泛而深刻的影响,并会对现有财务会计制度和企业的会计核算、信息披露、现金管理、内部控制、会计组织结构等产生挑战。为应对这些挑战,在会计法律制度建设方面,要确立数字人民币法定货币地位,明确数字人民币所有权流转规则,制订数字人民币会计准则,完善会计信息化制度规范;在企业内部会计监督方面,要重新配置会计岗位及其权责和义务,增设系统安全维护岗位,改造升级会计核算系统,强化会计信息系统内部审计;在数字人民币流通管理方面,要扩大数字人民币的使用范围,提高零星支付结算起点,降低库存现金限额,加强对大额数字人民币流通的监测。

关键词：数字人民币财务会计制度现金管理内部控制

不同工况下带式输送机自动张紧装置的动态特性模拟研究

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机械管理开发 2024年第7期39卷 39-41页

作者：温俊晋能控股煤业集团北辛窑煤业有限公司山西忻州036700

为实现带式输送机在不同工况下的正常运行需求,通过采用“控制变量法”,并结合应用AMESim和Matlab联合仿真,分析不同输送带载荷、弹性模量及阻尼对自动张紧装置的动态特性:满载工况相比于空载工况,自动张紧装置输出的功率更大,且游动小... 详细信息

为实现带式输送机在不同工况下的正常运行需求,通过采用“控制变量法”,并结合应用AMESim和Matlab联合仿真,分析不同输送带载荷、弹性模量及阻尼对自动张紧装置的动态特性:满载工况相比于空载工况,自动张紧装置输出的功率更大,且游动小车的速度峰值、位移均随弹性模量的减小而增大,达到速度峰值的时间越长;流变系数影响系统的稳定性,流变系数越大,系统的波动就越小。

关键词：带式输送机自动张紧装置弹性模量