基于模糊信息熵理论的港口物流系统竞争能力研究——以福州港智慧物流与低碳港口建设为例

在其深层次机理上,港口物流系统竞争能力必受其物质技术支撑体系的制约．结合智慧港口和第五代港口基本理论,可得出深层次物质技术支撑体系主要有：物质资源禀赋、城市经济系统、物联网系统、港口经营系统、绿色效率系统等．以相关港口物流系统竞争力基本理论为指导,考虑到中国各港口的实际情况,结合数据获得的难易程度,分别从基础设施、发展环境、智慧技术、服务水平、低碳绩效五个方面遴选出18个评价指标,按照模糊信息熵理论,利用全国24个主要港口2001—2013年的原始数据,通过数学软件Matlab编程,计算出系统层指标的信息熵和权重及全国8个代表性港口2013年的竞争能力综合评价值,并以福建省福州港为例,对其进行横向比较和纵向时序分析．     

New properties of the Busemann ellipsea

A combination of the Busemann ellipse, the inscribed unit circle and a circle of radius √2 about the same centre is considered. For supersonic two-dimensional potential gas flows, it is shown that the inclinations of the velocity vector in motion along an arbitrary characteristic, the characteristic itself and the characteristic of the other family have values equal to, respectively. the difference between the areas of the elliptical and circular (R = 1) sectors, the difference between the areas of the elliptical and circular (R = √2) sectors, and the area of the elliptical sector, apart from unimportant multiplicative and additive constants. The straight sides of the sectors in question are the semiminor antis of the ellipse and the radius vector of the velocity. The obvious analogy with one of Ke:pler's laws is pointed out. The existence of a point of intersection of the ellipse and the second circle illustrates a well-known result of Khristianovich concerning the points of inflexion of characteristics with a monotone velocity distribution. It is shown how the combination of the ellipse and the inscribed circle illustrates the simplification of the compatibility conditions and the Darboux equation for trans- and hypersonic flows.     

乡村绿色生态旅游适宜等级VIKOR评估方法

针对乡村绿色生态旅游特征,并考虑旅游者个体感受与群体效益,本文从乡村绿色生态旅游开发与适宜评级概念出发,提出乡村绿色生态旅游适宜等级VIKOR评估模型与方法。首先,从等级评估的概念与内涵出发,刻画乡村绿色生态旅游适宜评级问题,避免混淆旅游适宜评级和排序两个本质不同的问题。然后,构建乡村绿色生态旅游适宜等级评估指标及隶属函数,提出评估指标的熵权确定方法。其次,提出乡村绿色生态旅游适宜等级VIKOR评估模型与二元语义等级评估方法。最后,通过案例研究和比较分析,说明本文所提模型与方法的合理性、可行性与实用性。     

低碳环境友好技术政产学研金协同创新演化博弈研究

在气候变化应对日益紧迫的背景下,研究了政府、企业、研发机构和金融机构(政产学研金)参与低碳环境友好技术(LCEFT)创新的条件和策略。以企业合作关系为假设条件,引入金融主体和科研机构,构建了LCEFT的政产学研金协调创新博弈模型,深入分析了碳权质押、信用等级、投资回报等因素对博弈系统群体协调创新策略的影响。研究表明,金融机构参与协同创新的决策受到政府奖惩机制、绿色信贷项目盈利和风险等因素的影响;多主体在资源和能力上的互补性正是LCEFT协同创新联盟形成的关键;政府部门的奖惩机制能够促进多主体合作,但难以使得整体获得最优,达到整体最优的关键是有效地发挥政府部门的引导作用和金融机构的杠杆作用。本文为政府部门制定绿色金融、产学研协同创新及产业化管理机制提供了新思路和一定的决策参考。     

Tools of the mind: Techniques and methods for intellectual work: V. STIBIC North-Holland,Amsterdam, 1982, xiii + 297 pages,Dfl.85.00

Many location problems may be separated into a series of interrelated macro, meso and micro decision-making states. The macro scale decision determines the type, capacity and number of facilities, the meso scale decision determines the location and allocation of facilities and the micro scale decision determines such considerations as routing and scheduling of service vehicles. This paper concerns the first two levels of decision-making.The present paper demonstrates the use of two models: (i) an analytical model that uses continuum approximations and methods of calculus to determine the number of facilities, the capacity and the approximate location of each that minimizes the sum of the transportation and facility costs for a slowly varying demand rate, and (ii) a traditional location-allocation model that determines more exactly the resulting locations and allocations. These two approaches have specific requirements in terms of data input, cost of data collection and cost of solution and, consequently, yield unique insights and benefits for practising planners. The strengths and weaknesses of the two models are complementary. This thesis is developed with an analysis of the Calgary, Alberta refuse collection and disposal system.     

城市老旧居住小区交通环境评价指标与评价方法

定量的评判城市老旧居住小区整体交通环境质量并进而科学有效的提出老旧小区交通环境更新与改善措施,对城市老旧居住小区交通环境进行了调查,明确了老旧居住小区存在的突出交通问题,并提出了城市老旧居住小区交通环境评价的指标体系,包括行人跨路出行指数、无人行道路段长度占比、停车泊位供需比、路内非法停车占比、平均停车步行距离、泊位数量户数比、人均步行空间、无障碍通道、盲道设置比例、非机动车泊位供需比、地面停放车辆数小区面积比、外部穿行交通周转量小区面积比等。并给出了具体指标的计算方法与获得办法。以长沙市四个典型老旧居住小区为例,对评价方法进行了论证,并得到城市老旧居住小区存在的一般问题,包括人车混杂、人车交织现象严重,停车泊位短缺、车辆乱停乱放,交通设施、特别是弱势群体交通设施缺乏。给出的评价指标、评价方法与结论可为城市老旧小区改造更新,特别是其中很重要的交通环境更新提供决策依据。     

The buckling of a drill string in a curvilinear borehole with axial line imperfections

The problem of the elastic buckling of drill strings in the channels of deep curved boreholes with geometric axial line imperfections is formulated. Imperfections in the form of localized helices are considered. The relation between the forces resisting the motion of the string and the amplitudes, pitches and sites of localization of the imperfections is analysed. The distributed forces of contact and friction interaction between the drill string and the borehole surface are found and the effects of seizure of the drill string are established. It is shown that the resistive forces and their moments increase as the amplitudes of the imperfections increase, and as their pitches and the displacement of the zones where they are relocated from the lower most distorted parts to the upper least distorted parts, decrease.     

基于物元分析的科技人才考评研究

利用可拓学中的物元分析理论,对科技人才考评问题进行了研究.在分析多种相关因素的基础上,从基本素质、学术素质、业务素质和业绩贡献等方面构建了科技人才考评指标体系.对考评指标实行规范化、科学化、定量化的基础上,建立了科技人才考评的物元分析模型.最后应用结果表明,把物元分析理论应用于科技人才考评是可行的,同时,物元分析拓展科技人才考评的研究途径.     

On products and line graphs of signed graphs, their eigenvalues and energy

In this article we examine the adjacency and Laplacian matrices and their eigenvalues and energies of the general product (non-complete extended p-sum, or NEPS) of signed graphs. We express the adjacency matrix of the product in terms of the Kronecker matrix product and the eigenvalues and energy of the product in terms of those of the factor graphs. For the Cartesian product we characterize balance and compute expressions for the Laplacian eigenvalues and Laplacian energy. We give exact results for those signed planar, cylindrical and toroidal grids which are Cartesian products of signed paths and cycles.We also treat the eigenvalues and energy of the line graphs of signed graphs, and the Laplacian eigenvalues and Laplacian energy in the regular case, with application to the line graphs of signed grids that are Cartesian products and to the line graphs of all-positive and all-negative complete graphs.     

成渝地区双城经济圈核心城市的博弈分析与对策研究——以交通物流基础设施建设为例

推进成渝地区双城经济圈建设已经上升为国家发展战略.以交通物流基础设施建设为例,从个体理性和团体理性两个方面,对竞争状态、合作状态和混合状态三种情况分别构建博弈关系模型并求解,得出结论:在成渝地区双城经济圈建设交通物流基础设施的过程中,核心城市的个体利益大于团体利益,表现为个体理性与团体理性之间的冲突,即两者存在非合作博弈关系.最后针对核心城市存在的非合作博弈关系,提出促进成渝地区双城经济圈核心城市协同发展的对策建议.     

企业雇佣下残疾人就业行为研究——基于就业促进政策的演化博弈分析

融合就业是残疾人可持续发展的关键途径。基于演化博弈理论和残疾人就业促进政策,建立残疾人与用人单位(企业)行为交互过程的动态演化模型,用数值实验展示了初始条件改变和决策变量不同取值对系统演化结果的影响。研究发现,残疾人就业行为路径演化系统收敛于良好状态和“锁定”状态两种模式;调控模型中的参数收敛于不同模式的概率发生显著变化或变化不明显,揭示了现实中残疾人就业治理效果不理想的深层次原因;通过提高残疾人的工资待遇、心理收益、为企业创造的价值,减少残疾人的社会补助与就业付出的人力和社会资本,增加残疾人就业法定比例、企业雇佣残疾人的声誉收益、增值税退税优惠(企业符合退税条件)与雇佣残疾人数量,减少企业支持残疾人的就业投入等均能使系统演化到良好状态的概率增加。这为制定灵活有效的残疾人就业制度、政策与措施提供了较大的操作空间,多元主体协同治理,利益共享,良性互动,以跳出不良“锁定”状态,实现残疾人就业行为良序发展,破解就业难题。     

污染类邻避冲突事件共力耦合演化机理研究——基于耦合协调度模型

随着民主化进程的推进与公民环保意识的觉醒,由部分公共基础设施建设而诱发的邻避冲突事件逐年增多,并呈现出以抗议污染类项目为核心的发展趋势。污染类邻避冲突事件引致因素间耦合作用影响着事件演变方向,因而构建邻避冲突共力耦合模型,探究邻避冲突演化机理具有重要现实意义。基于耦合理论,在分析污染类邻避冲突事件发生的内在引致因素、外在引致因素、情绪引致因素、因素间共力耦合作用及事件内在演化机理的基础上,建立事件耦合度模型和耦合协调度模型,选取“余杭中泰垃圾焚烧厂事件”、“江苏启东事件”、“湖北仙桃垃圾焚烧发电厂事件”三起典型污染类邻避冲突事件探寻引致因素耦合度与邻避冲突发展演化的关系。研究发现,污染类邻避冲突事件引致因素耦合协调度与事件影响力值呈正相关关系,引致因素间耦合协调度与邻避冲突发展演化密切相关;情绪引致因素对污染类邻避冲突事件影响力起着强化推动作用,加速了事件的发展演化进程。研究结果为政府构建污染类邻避冲突事件引致因素阻断机制,多渠道化解民众群体情绪耦合力提供了新思路。     

Influence of Multiple Micro Cracks on the Damage Behavior of a Macro-Crack Tip北大核心CSCD

The solution of an infinite plane containing a macro crack and a cluster of micro cracks under uniaxial tensile load was presented based on Muskhelishvili’s complex function method and the stepwise recursive method. The stress field and stress intensity factor K were obtained. Combined with the damage mechanics, damage parameter D of the macro-crack tip and the micro-crack tip under uniaxial tension was redefined, and the influence of different damage zone forms on the damage of the crack tip was analyzed. The results show that, both the chain-distribution and the reverse-chain-distribution micro cracks have an amplifying effect on the macro crack growth, and the damage parameter increases with the decrease of the inclination angle of the micro crack and the reduction of the distance between the macro crack and the micro cracks. For a relatively small inclination angle of the micro crack, the damage parameters of the macro crack and the micro crack heightens, and the damage parameter of the macro crack increases with the micro-crack length. For evenly distributed micro cracks in the continuous damage zone, the micro cracks have an amplifying effect on the macro-crack growth, and the damage parameter of the macro crack increases with the micro-crack number. © 2022 Editorial Office of Applied Mathematics and Mechanics. All rights reserved.     

企业及市场经营效用函数形式研究

鉴于经营效用是企业制订战略决策和发展策略的重要影响因素,研究其基本效用类型,提出对应的函数形式,并在此基础上提出市场总体的综合经营效用测度方法。企业经营效用由自身经营效用和同业比较效用两部分线性合成,效用变量分别为企业单位盈利指标加权合成值及单位盈利水平与行业平均值的差,效用函数通过原点且单调,因此需将效用理论中对应于各种效用类型的对数函数、指数函数等进行坐标变换、旋转或对称。保守型和冒险型效用在定义域内分别为凹函数和凸函数,共组合为9种效用类型含81种基本函数形式,并给出各效用类型含义、经营特征和定价倾向。以市场份额作为各企业经营效用权重,构建幂平均效用合成模型作为市场总体综合经营效用测度。     

受约束高分子链的拉伸

高分子生物材料微观力学性质的定量刻画,以及先进生物微纳米技术与器件的发展均需要定量分析生物大分子等高分子链在复杂微环境中的统计热力学性质与行为.在实现这一目标的过程中,连续介质力学与统计热力学的交叉研究扮演着很重要的角色.针对这一领域的力学问题,该综述先从DNA分子的受力拉伸出发,通过引入描述高分子链统计热力学性质的几类理论模型,指出了蠕虫链相较其他理想随机链模型在描述半柔性高分子链力与构型变化关系时具有较为显著的优势,从而使得人们对高分子在复杂微环境下,统计热力学性质与行为的定性与定量认识在很大程度上取决于基于蠕虫链模型的相关研究进展.根据这一事实,通过回顾与梳理空间几何约束对高分子链随机构象分布影响、高分子链在拉力与约束同时作用时的统计热力学建模、以及基于高性能计算机的高分子链统计物理性质仿真等各方面研究的现状,系统总结了蠕虫链在不同约束与受力微环境下,其统计热力学性质与行为研究的最新进展和依旧存在的挑战性难题.最后,通过总结分析,指出了蠕虫链在复杂微环境下的统计热力学研究是从分子与细胞尺度理解生命现象、发展先进微纳米技术以及构建软物质本构关系的重要基础,目前已成为极富挑战性的力学交叉科学前沿课题.     

政府奖惩下供应链合作减排与低碳宣传的动态优化

为减少生产过程中碳排放对环境带来的不利影响,考虑到政府对制造商采取奖惩措施,以此为背景,针对供应链长期合作减排、低碳宣传的问题,构建微分博弈模型。考虑到产品需求受碳排放量和零售商低碳宣传努力的共同影响下,得出并分析了分散式和集中式决策下制造商和零售商的反馈均衡策略及产品碳排放量的最优轨迹,发现产品碳排放量的最优轨迹具有多种敛散性,且在集中式决策下实现了供应链利润和环境绩效的双赢。此外,还分析了政府奖惩力度对产品碳排放量的影响。最后结合算例对模型进行分析,为供应链的低碳化管理和政府奖惩政策的制定提供了理论参考。     

The thermodynamically consistent equations of a thermoelastic saturated porous medium

A phenomenological model of a porous medium saturated with fluid is considered with in the framework of the hypothesis of interpenetrating continua. Assuming that there are no phase transitions, that the contribution of pulsations to the stress tensor and kinetic energy is small, and the components of the medium are in thermal equilibrium, mass, momentum and energy equations and a law of conservation of compatibility of the deformations and velocities are formulated. Using a representation of the force of interaction of the components in the form of the sum of equilibrium and dissipative components, a new form of inequality is obtained for the rate of entropy production. A definition of a thermoelastic saturated porous medium is given. The symmetry group of such a medium is considered as a set of two groups, corresponding to the symmetry of the skeleton and the fluid. It is shown that, in the class of thermoelastic porous media with an arbitrary type of symmetry of the skeleton, the saturating fluid can only be an ideal fluid, while the thermodynamic potentials and the porosity, stresses and entropies determined by them do not depend on the temperature gradient and the relative fluid velocity. It is found that the condition of incompressibility of only one of the components of the medium leads to the elimination of the porosity from the governing relations, rather than to kinematic limitations. The limitations imposed on the governing relations by the principle of thermodynamic consistency and the requirement of independence of the choice of the frame of reference are investigated. A form of the governing relations, necessary and sufficient to satisfy these principles, is obtained. It is shown that the Biot equations are one of the forms of thermodynamically consistent governing relations. A thermodynamic validation of the effective-stress tensor is given.     

废弃食品回流再造问题的产品价格分析

针对废弃食品回流再造的食品安全问题,建立相关利益主体包括食品制造商、废弃食品收购者在各自独立以及作为利益共同体的不同条件下的优化模型,分析新生产食品价格和回流再造食品价格以及相应的利润、影响因素.结果表明:作为同一利益主体,生产制造昂贵食品对食品制造商获利不利,而回流再造成本越低,对食品制造商通过回流再造获利是有利的;若食品制造商和收购者各自独立决定价格,收购者进行回流再造的行为会干扰当前食品零售市场;由于回流再造食品的价格比较优势,在信息不对称时消费者会倾向选择回流再造食品.     

The harmonic oscillations of a viscoelastic rod of triangular cross-section

Two exact solutions of the plane strain problem of the harmonic oscillations of a viscoelastic rod, the cross-section of which is a right triangle, are proposed. Either the normal displacement and the shear stress or the shear displacement and the normal stress of the side surface of the rod are given. Six dimensionless parameters which affect the dynamic deformation process are derived. Two parameters characterize the contribution of the viscous properties with respect to the elastic properties, two others define the logarithmic decrement of the longitudinal and shear harmonic waves, and two other parameters affect the wavelength of the corresponding wave and the velocity of motion of the wave front of these waves. The velocities of both types of waves and their wavelengths turn out to be greater than the velocities and wavelengths of the corresponding elastic waves. It is shown that, for certain values of the viscosity and the oscillation frequency, pseudo-resonance frequencies are possible which are higher than the resonance frequencies for an elastic medium.     

考虑成员风险态度的零售商资金约束闭环供应链定价与回收决策

针对由制造商、回收商和资金约束的零售商组成的三级闭环供应链,考虑供应链成员面对市场需求不确定时表现出不同的风险态度,研究了闭环供应链的定价与回收决策问题。首先给出了产品的市场需求函数与回收商的回收成本函数;然后基于均值-方差法,构建了各成员和闭环供应链的效用函数;进一步地,依据博弈论的思想,确定了不同渠道权力结构下的最优零售价格、最优回收率和最优批发价格;最后分析了闭环供应链成员风险态度和贷款利率对供应链最优决策和效用的影响。研究表明,成员风险态度和贷款利率能够影响闭环供应链最优决策和效用,其中,风险规避的零售商和制造商对闭环供应链其他成员均有利,但是对自身和闭环供应链不利;风险规避的回收商对闭环供应链成员均不利;贷款利率的增长会降低成员和闭环供应链的效用。