曲面上赋值的分类

令K为k的有限生成域扩张,v是K的k-赋值,定义了赋值的高度.在此基础上,得到了曲面赋值的完整分类,以及赋值和超越幂级数的关系.     

一类曲线的定义域（英文）

设K为代数闭域k的有限生成扩域.C:f(x)=ayn为K上曲线,其中f是k上至少有3个单零点的多项式且n>3是正整数,n不是域k的特征的倍数,再设a■Kn,那么曲线C不能定义在k上,即曲线C:(x)=ayn不会k(a)同构于一条k上的曲线.     

周期序列的k错线性复杂度的期望值

有限域Fq上一个周期序列的k错线性复杂度被定义为通过改变每个周期至多k个比特所得到的最小线性复杂度.给出有限域Fq上pn周期序列的k错线性复杂度的期望,其中p是一个奇素数,q是模p2的原根,并且1≤k≤(p-1)/2.     

计算幂级数和函数的一些技巧

无穷级数是高等数学课程的一个重要内容,而求幂级数的和函数是其中教学的重点也是难点,许多学生在学习时深感无从下手.本文讨论了几种求幂级数的和函数的方法,比如定义法、逐项求导或逐项积分法,化为两个级数的乘积法,转化为微分方程求解法等.     

人体虚拟弹性系数的力学初步探讨

应用经典力学方法,建立人体处拉伸状态的力学模型。定义下肢与竖直面夹角θ为广义坐标。假设人体上身存在的弹性系数为k。下肢作微小摆动,利用拉格朗日方程解出K的数学表达式。通过数学式子可以说明k与下肢质量、下肢角速度、角加速度存在正比关系。     

三重级数收敛性的讨论

本文首先回顾了高等数学中级数的定义及相关性质,利用类比法文章定义了三重级数并证明了三重级数的若干重要性质。     

对黎曼函数的几点探讨

本文将黎曼函数f(s)=∞∑n-1n1/s表示为无穷积分的形式,从而得到f(s)的一个上界;利用贝努利数求出f(2k)的值,k∈N(★);给出f(s)的近似值的两种求法.     

Q~((n))的纯锥与斜群环K[Q~((n)),σ]上的平凡分次扩张

设V是除环K的全赋值环,且V≠K,Q是有理数域,σ:Q~((n))→Aut(K)是一个群同态,假设Q~((n))在K上的斜群环K[Q~((n)),σ]有左商环Q(K[Q~((n)),σ])。本文首先对Q~((n))的纯锥进行了完全地刻画,然后用它对K[Q~((n)),σ]上的平凡分次扩张进行了刻画。     

中国冰岛蓼属植物花粉形态的研究

采用光学显微镜和扫描电镜对国产冰岛蓼属Koenigia L. 9种植物的花粉形态进行了观察。结果表明：花粉均为球形；直径为17.0-32.5 μm（包括刺长）；萌发孔有7(-8)赤道环沟、散沟、散孔；外壁纹饰均为刺状。根据萌发孔类型和外壁纹饰，将该属花粉划分为3种类型，即细冰岛蓼型（Delicatulum-type）、大连线冰岛蓼型（Forrestii-type）及冰岛蓼型（Koenigia-type）。细冰岛蓼型花粉的主要特征是具7(-8)赤道环沟，覆盖层无穿孔，外壁纹饰为显著的长刺状，此种类型的植物有细冰岛蓼K. delicatula （Meisn.） Hara。大连线冰岛蓼型花粉的主要特征是具12散沟，覆盖层无穿孔，外壁纹饰为显著的长刺状，此种类型的植物有大连线冰岛蓼K. forrestii (Diels) Měsíek & Soják 及连线冰岛蓼K. nummularifolia (Meisn.) Měsíek & Soják。冰岛蓼型花粉的主要特征是具15，20(-30)散孔，覆盖层无穿孔，外壁纹饰为显著的长刺状，此种类型的植物有冰岛蓼K. islandica L.、蓝蕊冰岛蓼K. cyanandra (Diels) Měsíek & Soják、线茎冰岛蓼K. nepalensis D. Don、柔毛蓼K. pilosa Maxim.、陕甘蓼K. hubertii (Lingelsh.) Měsíek & Soják及青藏蓼K. fertilis Maxim.。结果表明冰岛蓼属的花粉形态具有重要的分类学意义，研究结果支持Koenigia的属的地位，大铜钱叶蓼Polygonum forrestii Diels和铜钱叶蓼P. nummularifolium Meisn.应从蓼属分叉蓼组Polygonum L. sect. Aconogonon Meisn.中移入冰岛蓼属中，细冰岛蓼、蓝蕊冰岛蓼、青藏蓼、陕甘蓼、线茎冰岛蓼和柔毛蓼应从蓼属头状蓼组Polygonum L. sect. Cephalophilon Meisn.中移入冰岛蓼属中。     

浅析函数项级数非一致收敛的证明

通过实例介绍了三种函数项级数非一致收敛的证明方法，即函数项级数非一致收敛的ε—N定义、确界法和柯西收敛准则。     

Optimal parametrization in numerical construction of curve

The application of the optimal parametric continuation method to constructing a solution set curve for a system of nonlinear algebraic or transcendental equations depending on a parameter is considered. There are discussed two approaches to solving this problem—the use of iterative methods and reduction to an initial value problem for a system of ordinary differential equations. The algorithm suggested in this paper can also be used for finding an appropriate initial approximation when solving a system of nonlinear algebraic or transcendental equations not depending on a parameter by an iterative method.     

The formal institutional context of informal entrepreneurship: A cross-national,configurational-based perspective

While previous comparative research has identified the formal institutional conditions that differentiate countries on their degree of informal entrepreneurship, this paper examines the characteristics that shape cross-national diversity in its type. Based on a series of fuzzy-set qualitative comparative analyses (fs/QCA) of 138 country cases, we find evidence of causal heterogeneity in the configuration of institutional conditions associated with entrepreneurial outcomes that are informal and growth-oriented and those that are informal and subsistence-oriented. Given our results, we propose that the formal institutional-based conditions that differentiate between types of informal sectors are best identified by the conjoint mixture of strength and weakness of state capabilities across multiple domains, rather than by uniform weakness, or voids, along all state functions. In our discussion, we explore the implication of our configurational-based findings for the comparative analysis of national systems of informal entrepreneurship and for the tailoring of policies to account for the multiple institutional-based pathways by which entrepreneurs come to enter into the informal economy.     

Embedded ethics: some technical and ethical challenges

This paper pertains to research works aiming at linking ethics and automated reasoning in autonomous machines. It focuses on a formal approach that is intended to be the basis of an artificial agent’s reasoning that could be considered by a human observer as an ethical reasoning. The approach includes some formal tools to describe a situation and models of ethical principles that are designed to automatically compute a judgement on possible decisions that can be made in a given situation and explain why a given decision is ethically acceptable or not. It is illustrated on three ethical frameworks—utilitarian ethics, deontological ethics and the Doctrine of Double effect whose formal models are tested on ethical dilemmas so as to examine how they respond to those dilemmas and to highlight the issues at stake when a formal approach to ethical concepts is considered. The whole approach is instantiated on the drone dilemma, a thought experiment we have designed; this allows the discrepancies that exist between the judgements of the various ethical frameworks to be shown. The final discussion allows us to highlight the different sources of subjectivity of the approach, despite the fact that concepts are expressed in a more rigorous way than in natural language: indeed, the formal approach enables subjectivity to be identified and located more precisely.     

政府补贴对废旧电子产品双回收渠道价格竞争的引导作用研究

研究政府补贴对废旧电子产品正规和非正规回收渠道价格竞争的引导问题,即政府给予正规回收商补贴鼓励其回收废旧产品,建立了正规和非正规回收商并存的双回收渠道竞争模型。研究表明：随着补贴的增加,正规回收商的回收量增加,非正规回收商的回收量减少,但两者回收量之和增加;随着补贴的增加,两者的回收价都有不同程度的提高,且回收品在不同质量区间内,当非正规回收商与正规回收商处理废旧产品获得的单位利润之差小于政府补贴时,正规回收商的回收价较高,否则相反;补贴越高,正规回收商的利润越多,非正规回收商的利润越少;补贴能引导正规回收渠道并抑制非正规回收渠道,且非正规回收渠道的存在使政府补贴发挥更大的作用。     

The paradox of openness: Appropriability,external search and collaboration

To innovate, firms often need to draw from, and collaborate with, a large number of actors from outside their organization. At the same time, firms need also to be focused on capturing the returns from their innovative ideas. This gives rise to a paradox of openness—the creation of innovations often requires openness, but the commercialization of innovations requires protection. Based on econometric analysis of data from a UK innovation survey, we find a concave relationship between firms’ breadth of external search and formal collaboration for innovation, and the strength of the firms’ appropriability strategies. We show that this concave relationship is stronger for breadth of formal collaboration than for external search. There is also partial evidence suggesting that the relationship is less pronounced for both external search and formal collaboration if firms do not draw ideas from or collaborate with competitors. We explore the implications of these findings for the literature on open innovation and innovation strategy.     

Organizing links with science: Cooperate or contract?: A project-level analysis

Links with science have been argued to improve the (innovation) performance of firms. Yet we still know comparatively little about the project-level characteristics affecting the organization of such links. Our study, based on a sample of 52 projects carried out by a multinational company in the semiconductor industry, reveals that the knowledge attributes of a project help in predicting how the R&D activities will be organized. In particular, basic projects are likely to be developed through formal cooperative agreements with universities. Such projects also tend to be strategically less important. For strategically more important projects, in contrast, and for those where the knowledge to be developed is particularly novel to the firm, the firm is more likely to resort to formal contracting with a university for a specific component of the R&D project, usually early on in the project.     

实二次代数函数域的单位群

对于实二次代数函数域K,给出了求K的基本单位ε的一个方法。利用此方法,对于 4个系列(细分为 1 6类)的实二次代数函数域K,明显决定出了它们的基本单位     

地区社会资本对企业协同创新的影响研究

协同创新已成为企业实现技术创新的重要方式，但地区社会资本如何影响协同创新的研究却不充分。本文以2012年世界银行中国营商环境调查数据为研究样本，考察了地区社会资本对企业协同创新的影响。研究发现，地区社会资本对企业协同创新具有“促进作用”，企业所在地区的社会资本水平越高，其协同创新的可能性越高、投入力度越大。同时，社会资本的促进作用在企业机会主义行为问题较为严重的高技术密集型行业和法制环境较差地区更为明显。进一步研究发现，社会资本的促进作用主要体现在创新能力较弱、融资约束较为宽松等协同创新意愿较强的企业。     

A method for the closed-form evaluation of critical buckling loads for planar strongly curved bars

The calculation of critical buckling loads of planar curved bars, subjected to a general co-planar continuous external load (or a general co-planar terminal loading), leads to the solution of transcendental (nonlinear) equations. In this investigation a new method for the closed-form solution of such types of equations is presented. In particular, the transcendental equation u tan γ cot uγ = 1, corresponding to the buckling problem of a cantilever circular bar of high curvature loaded by two co-planar forces acting along its chord, is solved in a closed-form. Finally, several numerical results are presented, based on the Gauss integration rule.