Dynamical behavior of fractional‐order energy‐saving and emission‐reduction system and its discretization

This paper attempts to explore dynamical behavior and mathematical properties of the three‐dimensional fractional‐order energy‐saving and emission‐reduction system. Theoretically, the conditions of local stability of fractional‐order system's equilibrium points are obtained. Numerical investigations on the dynamics of this system are carried out, and the existence of the asymptotically stable attractor is found. Combined with the fractional‐order subsystem, we discuss the relationship between energy‐saving and emission‐reduction and economic growth, and carbon emissions and economic growth. Furthermore, we discretize the fractional‐order system and give necessary and sufficient conditions of its stabilization. It is shown that the stability of the discretization system is impacted by the system's fractional parameter. Numerical simulations show the richer dynamical behavior of the fractional‐order system and verify the theoretical results. Recommendations for Resource Managers

• The impact of carbon emissions on economic growth is one of the main reasons for energy‐saving and emission‐reduction.
• Control measures on people's low‐carbon life through government intervention are required to protect the natural environment.
• New energy‐saving and emission‐reduction technologies should be implemented to achieve sustainable social and economic development.

     

基于广义脉冲的东北三省外贸外资与经济增长研究

作为连接其他国家和地区的桥梁和纽带,对外经贸在国际经济关系中有着十分重要的地位。本研究选取对外经贸与经济增长代表性指标,以各指标平均增长率为切入点,通过构建相对增长指数模型,测算东北三省的外贸相对增长指数(TGI)和外资相对增长指数(CGI)并进行分类,结果显示三省外贸、外资增长类型截然不同。进一步,将历年外贸、外资增速与经济增速进行对比分析发现,外贸增速与经济增速具高度同步性,且始终扮演经济晴雨表的角色,外资增速则更具不确定性和偶然性。最后,广义脉冲响应分析显示外贸外资冲击经济增长均产生显著效应,但响应程度不尽相同,各指标贡献度通过方差分解呈现。本文为外贸外资与经济增长关系研究提供了新的视角。     

中国汽车制造业的整体发展状况及主要省市的产业发展态势

汽车制造业逐渐发展成为中国经济的支柱产业,成为中国不少地区最具活力的区域产业经济增长点.以"中国汽车制造业的整体发展状况"和"国内主要省市汽车制造业的产业发展态势"为研究内容,概括和综述中国汽车制造业的发展动态,并以此为基础观察和分析中国汽车制造业的产业发展,包括中国汽车制造业产业总体发展状况、汽车产业的区域产能分布、汽车产业区域布局的演化格局、主要省市的汽车制造业发展状况.     

Baseline models are not “finishline” models: A sympathetic critique of Mayhew's strategy

A rationalist view of Relative Deprivation is possible if it is represented with extended preference. In the social movements studies, the concept of relative deprivation has been treated as an intervening variable, which is determined by the interpersonal comparisons and causes the social movements. The most important problem is whether a relatively deprived individual has an incentive for social movements or not. On the one hand he has different reference persons to whom he experiences relative deprivation and a sense of his subjective welfare, which make him behave in respective ways. But on the other hand he can behave in only one way at one time. We formalize the concept of the relative deprivation and construct the model that the relative deprivation and his preference in the ordinary sense are both the factors determining his behavior. Then it is deduced that there's no effect of the feeling relative deprivation for each individual to decide his way under some adequate conditions. So it should be concluded that the concept of the relative deprivation is not effective to explain social movements or social change in collectivities.     

基于差分的等级依赖效用模型行为决策权重扩展(英文)

基于等级依赖期望效用模型(RDEU),提供了一个简单但有效的行为决策权重扩展.因结果序列具有直线增长趋势,介绍一种基于一阶差分的新权重,并证明其对拆分效应的有效性.差分权重和RDEU权重的凸组合构成最终决策权重命名为D'-RDEU权重,它不仅可继承RDEU的优点,也可克服RDEU的两个不足.特别是,它通过拆分获得随机优势,可从理论上解释拆分效应.也提供了连续形式的D'-RDEU模型,连续模型的存在证明D'-RDEU比D-RDEU更实用.     

Data aggregation and Simpson’s paradox gauged by index numbers

Simpson’s paradox is a phenomenon occurring in data aggregation in complex systems. It consists in the increase (decrease) of the rate in the data aggregate at the higher level with the simultaneous decrease (increase) of the rate in each subgroup of the lower levels of the hierarchy. Although the nature of this paradox is known, it is difficult to interpret it without gauging the reasons of its occurrence. To capture the causes of the paradox, we elaborated some measures of index analysis. We suggest to apply these measures for estimation of changes due to the partial rates and the structural effects. Using numerical examples from the marketing research field, we show how the elaborated gauges evaluate absolute and relative changes, helping to interpret the incidence cases.     

中国地方政府财政民生支出效率实证分析

利用DEA方法计算出2009-2013年5年间全国31个省份财政民生支出资金配置的综合技术效率、纯技术效率、规模效率三种效率值,分析出各省份政府财政民生支出所处规模报酬阶段.结果显示:大部分省份的政府财政民生支出DEA得分在0.9以上,说明虽然效率没有达到最优水平,但是总体来说效率水平还是比较高的.另外,各省市财政民生产出存在较大的差异,东部地区综合产出水平高于中西部地区,其中,西部地区效率最低,改进空间最大.     

城市“精明增长”的数学模型研究

城市"精明增长"是为了管理城市蔓延的恶性增长状态,以建设经济繁荣、社会公平、环境可持续发展的城市为目标。在考虑城市的经济、社会、环境和人口为衡量精明增长的主要指标的情况下,为了研究城市的可持续发展,建立微分方程模型,以实际数据为依据,来研究各指标对城市精明增长的影响和对未来城市可持续发展的调控作用。     

A Well-Conditioned,Nonconforming Nitsche's Extended Finite Element Method for Elliptic Interface Problems

In this paper, we introduce a nonconforming Nitsche's extended finite element method (NXFEM) for elliptic interface problems on unfitted triangulation elements. The solution on each side of the interface is separately expanded in the standard nonconforming piecewise linear polynomials with the edge averages as degrees of freedom. The jump conditions on the interface and the discontinuities on the cut edges (the segment of edges cut by the interface) are weakly enforced by the Nitsche's approach. In the method, the harmonic weighted fluxes are used and the extra stabilization terms on the interface edges and cut edges are added to guarantee the stability and the well conditioning. We prove that the convergence order of the errors in energy and $L^2$ norms are optimal. Moreover, the errors are independent of the position of the interface relative to the mesh and the ratio of the discontinuous coefficients. Furthermore, we prove that the condition number of the system matrix is independent of the interface position. Numerical examples are given to confirm the theoretical results.     

Relative essential spectra involving relative demicompact unbounded linear operators

In this article, we introduce the concept of demicompactness with respect to a closed densely defined linear operator, as a generalization of the class of demicompact operator introduced by Petryshyn in [24] and we establish some new results in Fredholm theory. Moreover, we apply the obtained results to discuss the incidence of some perturbation results on the behavior of relative essential spectra of unbounded linear operators acting on Banach spaces. We conclude by characterizations of the relative Schechter's and approximate essential spectrum.     

A model of ambition,aspiration and happiness

Can payoffs buy happiness? People's perception on their current payoffs depends on the social context and the historical context. This paper develops a utility model that captures both effects of interpersonal comparisons and self-adaptations in evaluating time streams of payoffs. Moment utility represents subjective happiness over payoffs, which hinges on three state variables: retaliation, aspiration, and ambition. Retaliation incorporates insights of fairness thinking and formulates people's psychological reaction on relative payoff comparisons interpersonally. Aspiration displays habit formation that formulates people's self-adaptation on their own history of payoffs. Ambition captures the net influence of the past situations to the present. Over a time window, our model delivers a new measure of individual well-being under both social and historical contexts.     

Using the Tower of Hanoi puzzle to infuse your mathematics classroom with computer science concepts

This article suggests that logic puzzles, such as the well-known Tower of Hanoi puzzle, can be used to introduce computer science concepts to mathematics students of all ages. Mathematics teachers introduce their students to computer science concepts that are enacted spontaneously and subconsciously throughout the solution to the Tower of Hanoi puzzle. These concepts include, but are not limited to, conditionals, iteration, and recursion. Lessons, such as the one proposed in this article, are easily implementable in mathematics classrooms and extracurricular programmes as they are good candidates for ‘drop in’ lessons that do not need to fit into any particular place in the typical curriculum sequence. As an example for readers, the author describes how she used the puzzle in her own Number Sense and Logic course during the federally funded Upward Bound Math/Science summer programme for college-intending low-income high school students. The article explains each computer science term with real-life and mathematical examples, applies each term to the Tower of Hanoi puzzle solution, and describes how students connected the terms to their own solutions of the puzzle. It is timely and important to expose mathematics students to computer science concepts. Given the rate at which technology is currently advancing, and our increased dependence on technology in our daily lives, it has become more important than ever for children to be exposed to computer science. Yet, despite the importance of exposing today's children to computer science, many children are not given adequate opportunity to learn computer science in schools. In the United States, for example, most students finish high school without ever taking a computing course. Mathematics lessons, such as the one described in this article, can help to make computer science more accessible to students who may have otherwise had little opportunity to be introduced to these increasingly important concepts.     

A new modified resource budget model for nonlinear dynamics in citrus production

Alternate bearing or masting is a general yield variability phenomenon in perennial tree crops. This paper first presents a theoretical modeling and simulation study of the mechanism for this dynamics in citrus, and then provides a test of the proposed models using data from a previous 16-year experiment in a citrus orchard. Our previous studies suggest that the mutual effects between vegetative and reproductive growths caused by resource allocation and budgeting in plant body might be considered as a major factor responsible for the yield oscillations in citrus. Based on the resource budget model proposed by Isagi et al. (J Theor Biol. 1997;187:231-9), we first introduce the new leaf growth as a major energy consumption component into the model. Further, we introduce a nonlinear Ricker-type equation to replace the linear relationship between costs for flowering and fruiting used in Isagi's model. Model simulations demonstrate that the proposed new models can successfully simulate the reproductive behaviors of citrus trees with different fruiting dynamics. These results may enrich the mechanical dynamics in tree crop reproductive models and help us to better understand the dynamics of vegetative-reproductive growth interactions in a real environment.     

Modelling and computing the peaks of carbon emission with balanced growth

In this paper, we assume that under the balanced and optimal economic growth path, the economic growth rate is equal to the consumption growth rate, from which we can obtain the ordinary differential equation governing the consumption level by solving an optimal control problem. Then, a novel numerical method, namely a so-called discontinuous Galerkin method, is applied to solve the ordinary differential equation. The error estimation and the superconvergence estimation of this method are also performed. The model’s mechanism, which makes our assumption coherent, is that once the energy intensity is given, the economic growth is determined, followed by the GDP, the energy demand and the emissions. By applying this model to China, we obtain the conclusion that under the balanced and optimal economic growth path the CO₂ emission will reach its peak in 2030 in China, which is consistent with the U.S.-China Joint Announcement on Climate Change and with other previous scientific results.     

A Relational Perspective on Issues of Cultural Diversity and Equity as They Play Out in the Mathematics Classroom

In this article, we present a relational perspective in which cultural diversity is viewed as a relation between people's participation in the practices of different communities. In the case at hand, the relevant practices were those of students' local, home communities, and the broader communities to which they belonged in wider society on the one hand and the specifically mathematical practices established by the classroom community on the other hand. In the 1st part of the article, we discuss how we might characterize the practices of these various communities by drawing on Wenger's (1998) notion of a community of practice and on Gee's (1997) notion of a Discourse. In doing so, we question the manner in which students are frequently classified exclusively in terms of the standard categories of race and ethnicity in investigations of equity in mathematics education. Later in the article, we clarify that in addition to focusing on the continuities and contrasts between the practices of different communities, the relational perspective also encompasses issues of both power and identity. As we illustrate, the gatekeeping role that mathematics plays in students' access to educational and economic opportunities is not limited to differences in the ways of knowing associated with participation in the practices of different communities. Instead, it also includes difficulties that students experience in reconciling their views of themselves and who they want to become with the identities that they are invited to construct in the mathematics classroom.     

中国住房开发投资空间聚集变动及影响因素研究

本文基于中国1998~2014年度各省住房开发投资数据,运用Moran’s I指标测度了各年度住房开发投资的空间聚集指数,测度结果表明中国的住房开发投资呈现出典型的空间聚集特征,且在不同的年份随着社会经济发展形势的变化,空间聚集的程度也发生相应的变动。通过建立多元线性回归模型,对影响中国住房开发投资空间聚集变动的因素进行实证研究,结果表明经济增长率、产业升级、基础设施投资、人口城市化对房地产投资空间聚集水平的变化有着显著的影响。     

基于模糊影响图的我国居民消费水平的评价研究

为了评价我国居民消费水平的变动及其影响因素之间的相互作用及影响,本文运用模糊影响图的方法,从需求方面、基础设施、经济环境、政策环境以及消费者自身五个方面选取了影响消费的十六个指标,并对这些指标进行评价分析。结果表明,我国居民消费水平增长幅度缓慢,无明显变化。根据这一评价结果,结合消费影响因素影响图的拓扑结构得出,对外开放程度、社会保障水平、消费习惯以及居民受教育程度是导致消费增长缓慢的主要原因,进而提出对策建议。为今后提高我国居民消费水平方面的研究和我国相关政策的实施提供了理论借鉴和实践指导。     

Characterizing Belnap's Logic via De Morgan's Laws

The aim of this paper is technically to study Belnap's four-valued sentential logic (see [2]). First, we obtain a Gentzen-style axiomatization of this logic that contains no structural rules while all they are still admissible in the Gentzen system what is proved with using some algebraic tools. Further, the mentioned logic is proved to be the least closure operator on the set of {Λ, V, ?}-formulas satisfying Tarski's conditions for classical conjunction and disjunction together with De Morgan's laws for negation. It is also proved that Belnap's logic is the only sentential logic satisfying the above-mentioned conditions together with Anderson-Belnap's Variable-Sharing Property. Finally, we obtain a finite Hilbert-style axiomatization of this logic. As a consequence, we obtain a finite Hilbert-style axiomatization of Priest's logic of paradox (see [12]).     

中国能源消费、碳排放与经济增长的区域差异性研究

基于1990～2010年我国30个省市面板数据,采用面板计量分析方法,考察我国源消费、碳排放与经济增长三者之间相互影响关系对空间区域的依赖性.研究结果表明:能源消费、碳排放与经济增长三者之间不仅存在着相互影响的关系,且具有显著的区域差异性.各省份的经济发展均为各地区能源消费增长的重要诱因之一,这与能源消费与经济增长具有较高关联度的结论保持一致.北京、辽宁、吉林等16个省份碳排放变化与经济增长变化之间的的弹性系数为负值,而天津等其他14个省市碳排放总量还将伴随着经济增长而增长,所以弹性系数为正值,这点隐含说明当区域经济水平较高时,该区域也将拥有更多优势条件来减低碳排放,实现碳减排最终还是需要依赖于发达的经济水平.     

产业转移、人力资本积累与中部经济增长

本文通过理论分析得出产业转移、人力资本和中部经济增长的假定假设,利用安徽省1990-2006年的时序数据和基于向量自回归的多元协整方法,对每个假设进行了实证研究。实证分析结果表明:一个地区的人力资本水平对地区的经济增长具有促进作用,而且不同程度的人力资本的影响是不同的;在存在技术进步的情况下,产业转移对转入地经济增长率的贡献取决与人力资本的积累;但是与理论分析不同的是,初中文化程度的人力资本对经济增长的贡献要大于高中和大学程度人力资本的贡献。