首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
There is a growing interest in applying mathematical theories and methods from topology, computational geometry, differential equations, fluid dynamics, quantum statistics, etc. to describe and to analyze scientific regularities of diverse, massive, complex, nonlinear, and fast changing data accumulated continuously around the world and in discovering and revealing valid, insightful, and valuable knowledge that data imply. With increasingly solid mathematical foundations, various methods and techniques have been studied and developed for data mining, modeling, and processing, and knowledge representation, organization, and verification; different systems and mechanisms have been designed to perform data-intensive tasks in many application fields for classification, predication, recommendation, ranking, filtering, etc. This special focus of Mathematics in Computer Science is organized to stimulate original research on the interaction of mathematics with data and knowledge, in particular the exploration of new mathematical theories and methodologies for data modeling and analysis and knowledge discovery and management, the study of mathematical models of big data and complex knowledge, and the development of novel solutions and strategies to enhance the performance of existing systems and mechanisms for data and knowledge processing. The present foreword provides a short review of some key ideas and techniques on how mathematics interacts with data and knowledge, together with a few selected research directions and problems and a brief introduction to the four papers published in the focus.  相似文献   

2.
维修保障船能够实现远海受损舰船的现场维修,当其进入舰船维修市场时将与修船厂形成一定程度的竞争。为解决维修保障船模式与修船厂模式维修远海受损舰船的最优定价问题,通过分析这两种维修模式在时空以及成本方面的差异,建立维修保障船与修船厂的定价博弈双层规划模型,并设计迭代算法实现模型的求解。以维修远海船体受损的舰船为例,求得了两者的最优定价、最大收益以及船东对两种维修模式的需求,验证了模型与算法的有效性,并分析了调遣距离、舰船受损程度、海上维修技术难度等因素对维修保障船与修船厂定价博弈的影响。该方法能够为维修保障船与修船厂的经营者提供最优定价策略,为两种维修模式的定价博弈提供理论支持。  相似文献   

3.
准正交基与准正交变换   总被引:12,自引:0,他引:12  
利用内积给出了准正交基,准正交变换与准对合变换的概念,研究了它们的性质及其之间的联系,获得了许多新的结果,推广了正交基,正交变换,对合变换的概念,性质以及张禾瑞,郝新,邹本强等先生的相关结果。  相似文献   

4.
5.
随着当代科学和技术的发展,复杂非线性系统和控制理论研究不断深入,应用领域不断扩大,已影响了科技和社会领域的许多方面.针对当今该领域的研究难点和重点,本文集中讨论了复杂非线性系统控制研究中的3个关键问题,包括非光滑系统控制、网络化系统控制、临界态分析与控制.一方面是对在相关研究领域中的部分科研成果做一个简要的总结;另一方面,想借此机会在自动化学会控制理论专业委员会成立50周年之际向专业委员会表示感谢和祝贺.  相似文献   

6.
With reference to a short compulsory module for MBA students, this paper discusses how, despite a range of pressures and an extraordinary range of student backgrounds, fears and motivations, it is possible to quickly facilitate understanding and confidence in handling data and basic statistics for graduates in business and associated workplaces. Links and contrasts with a variety of undergraduate teaching scenarios help to enrich teaching and learning strategies, and the strategies and materials developed through interaction with the range of MBA students are transferable to other postgraduate coursework situations. In particular, the need for understanding and confidence in handling data and its presentation, in considering categorical and simple continuous data, and in understanding correlation and association, are common across many different workplaces and applications.  相似文献   

7.
高等院校教育成本核算一直是人们关心的重要问题.把高等院校大学生培养过程,看作人才的生产与加工过程,投入高中毕业生(原材料)以及教学、办公楼等固定资本与教职员工等劳动工时,生产或毕业高校大学毕业生,从而建立高等教育的动态投入产出模型,并由此推导高等院校大学生教育成本的计算公式,指出在计算教育成本时,固定资本租金率与高校规模扩张速度之间的关系,指出进一步深入研究的方向.  相似文献   

8.
卢荣花  李南 《运筹与管理》2015,24(6):112-120
研究产品生命周期条件下一个制造商、一个零售商组成的闭环供应链的定价和协调策略:制造商第一周期只生产新品,从第二周期开始生产再制造品,并负责回收。建立了两周期、多周期和无限周期下的分散决策模型和多周期下的集中决策模型,得到最优定价和生产策略。结果表明:两周期中,制造商和零售商应根据不同的成本节约额制定不同的批发价、零售价和生产量。多周期中,当成本节约额比较小时,除第一和最后一个周期外,制造商和零售商应采取相同的定价和生产策略;当成本节约额比较大时,除第一和最后两个周期外,制造商和零售商应采取相同的定价和生产策略。无限周期中,除第一周期以外,制造商和零售商都应该采取相同的定价和生产策略。在有限周期情况下,制造商和零售商应通过在前期制定比较低的批发价和零售价,以提高生产量和销售量,使得后期的回收量增大,达到降低成本的目的。通过引入收益共享契约制定合适的批发价和销售收入及再制造收益共享比率可以协调整个闭环供应链。算例验证了上述结论。  相似文献   

9.
赵焕焕  菅利荣  刘勇 《运筹与管理》2020,29(10):190-197
复杂装备研制主体间呈现社会关系、合作关系、协调关系等网络关系,并且相互影响相互作用,其影响复杂装备研制的重要参数。为有效描述在资源环境约束下制造商和供应商的关系,探讨复杂装备研制协调机理与实现路径,本文利用超网络方法,设计了相互影响、相互作用的社会关系网络、协调网络和合作网络的复杂装备研制协调超网络,并将社会关系水平、协调度和合作水平作为超网络的3个决策变量,建立基于关系价值最大、协调成本最低、协调风险最小、合作收益最大、合作风险最小和成本最小等不同偏好下的多目标最优决策模型,构建了复杂装备研制超网络均衡模型,并利用其探讨超网络均衡和实现路径。  相似文献   

10.
小区域科技实力及其评估体系   总被引:3,自引:0,他引:3  
科技实力是运作主体能够进行并完成科技活动的能力。科技实力是一个评估性概念,它反映了科学技术的创新,发展,转移,推广,储备条件以及管理,效果等不同层面的综合性的特征,科技实力由科技潜在能力(科技势能),科技显现能力(科技动能)构成,它包含了对科技资源及分布状态,科技资源保障能力,科技创新能力,科技开发能力,科技转移能力和科技活动运作能力的综合描述。  相似文献   

11.
Munir Fasheh Dr. 《ZDM》1998,30(3):78-81
How we perceive and define concepts should be a major concern for teachers and educators in general and for math teachers and educators in particular. This issue, however, is usually ignored or marginalised in curricula and classrooms, where textbooks form the major source of information, knowledge, meanings and definitions. The two words in the theme of this ZDM-issue—math and peace—are themselves good examples to explore. “What do we include in the math curriculum and what do we exclude, and why?” and “What do we mean by peace, and whose peace, and at what human and environmental cost?” are questions that the article raises and tries to point out how we should go about dealing with them. The article challenges the absolute meanings of concepts and stresses the importance of discussing meanings only within context. This concern requires giving teachers and students a greater say in the curriculum, to explore and discuss issues that affect their lives profoundly. The article challenges current values and goals, and suggests what it considers more fundamental values. In particular, it suggests that when there is conflict between peace and being true to our humanity, the latter should be given priority as a guiding value.  相似文献   

12.
Abstract The paper compares the management outcomes with a total allowable catch (TAC) and a total allowable effort (TAE) in a fishery under uncertainty. Using a dynamic programming model with multiple uncertainties and estimated growth, harvest, and effort functions from one of the world's largest fisheries, the relative economic and biological benefits of a TAC and TAE are compared and contrasted in a stochastic environment. This approach provides a decision and modeling framework to compare instruments and achieve desired management goals. A key finding is that neither instrument is always preferred in a world of uncertainty and that regulator's risk aversion and weighting in terms of expected net profits and biomass, and the trade‐offs in terms of expected values and variance determine instrument choice.  相似文献   

13.
Grid technologies and the related concepts of utility computing and cloud computing enable the dynamic sourcing of computer resources and services, thus allowing enterprises to cut down on hardware and software expenses and to focus on key competencies and processes. Resources are shared across administrative boundaries, e.g. between enterprises and/or business units. In this dynamic and inter-organizational setting, scheduling and pricing become key challenges. Market mechanisms show promise for enhancing resource allocation and pricing in grids. Current mechanisms, however, are not adequately able to handle large-scale settings with strategic users and providers who try to benefit from manipulating the mechanism. In this paper, a market-based heuristic for clearing large-scale grid settings is developed. The proposed heuristic and pricing schemes find an interesting match between scalability and strategic behavior.  相似文献   

14.
在集中式和分散式决策条件下,应用两阶段优化技术和Stackelberg博弈的理论与方法,对一个制造商与一个零售商组成的双渠道供应链,重点考虑了制造商在网络渠道的服务决策,建立了利润最大化模型,得到了最优的价格策略和服务策略,研究表明,网络渠道的服务水平对制造商和零售商的价格决策有着重要影响,而且消费者对网络直销渠道的偏好对制造商和零售商价格决策和服务决策会产生很大影响.  相似文献   

15.
This paper presents the insights gained from the use of data mining and multivariate statistical techniques to identify important factors associated with a country's competitiveness and the development of knowledge discovery in databases (KDD) models to predict it. In addition to stepwise regression and weighted non-linear programming techniques, intelligent learning techniques (artificial neural networks), and inferential techniques (classification and regression trees), were applied to a dataset of 43 countries from the World Competitiveness Yearbook (WCY). The dataset included 55 variables on economic, internationalization, governmental, financial, infrastructure, management, science and technology, as well as demographic and cultural characteristics. Exploratory data analysis and parameter calibration of the intelligent method architectures preceded the development and evaluation of reasonably accurate models (mean absolute error <5.5%), and subsequent out-of-sample validations. The strengths and weaknesses of each of the KDD techniques were assessed, along with their relative performance and the primary input variables influencing a country's competitiveness. Our analysis reveals that the primary drivers of competitiveness are lower country risk rating and higher computer usage, in entrepreneurial urbanized societies with less male dominance and basic infrastructure, with higher gross domestic investment, savings and private consumption, more imports of goods and services than exports, increased purchase power parity GDP, larger and more productive but not less expensive labor force, and higher R&;D expenditures. Without diminishing the role and importance of WCY reports, our approach can be useful to estimate the competitiveness of many countries not included in WCY, while our findings may benefit policy makers and international agencies to expand their own abilities, insights and establish priorities for improving country competitiveness.  相似文献   

16.
定积分概念中蕴涵的对立统一思想   总被引:1,自引:0,他引:1  
讨论了定积分定义中所蕴涵的对立统一思想,并从直与曲、整体与局部、近似与精确、有限与无限、特殊与一般、常量与变量等十个方面进行了论述.  相似文献   

17.
耿申  乔晗 《运筹与管理》2022,31(10):169-175
为测度环境治理政策波动对产出、减排、要素配置、消费与产业结构的影响及其传导机制,将异质性消费偏好、产出差异性、环境效用和环境损失函数引入E-DSGE模型。政策强度分析发现,技术进步、排污税和消费税政策效果较强,环境控制和治污支出冲击效果较弱。政策效应分析发现,技术进步政策效应最优,能实现增产和减排双重目标,促进要素配置和居民消费、产出与消费结构改进;排污税和政府治污支出政策次优,能实现增产和减排的双赢目标,促进要素供给和产出结构清洁化,不利于消费提升和消费结构优化;环境控制与消费税政策效果最差,以牺牲产出实现减排,不利于要素配置,产出与消费结构改进效果较弱,消费税会抑制居民消费,但消费税政策效果随环境友好型家庭比例提升而加强。  相似文献   

18.
为研究农业科技资源错配与农业科技创新全要素生产率之间的空间溢出效应,利用2005-2017年所选取的25个省份的面板数据,通过动态空间杜宾模型进行实证研究.研究显示:①农业科技人力、财力资源错配与农业科技创新全要素生产率存在较强的空间相关性且分别呈现负向的区域内和区域间空间溢出效应.②农业科技财力资源错配程度每提升1%...  相似文献   

19.
In this study, we derive stochastic models of population dynamics and devise a new method of estimating the models. The models allow growth and harvest to be nonlinear functions of stochastic processes and the error terms to be nonlinear and heteroskedastic. Ordinary least-squares estimates would be biased and inefficient and generalized least-squares estimates cannot be calculated. Therefore, we implement nonlinear maximum likelihood methods to find unbiased and efficient estimates of parameters. The method is applied to the population dynamics of kangaroos in South Australia. Aerial survey data of kangaroo numbers are combined with harvest, effort and rainfall data to estimate the growth and harvest functions and the variances of the stochastic processes which drive the system. Results suggest that growth and harvest should be modeled as functions of stochastic processes and that observations on kangaroo numbers are critical for estimating population dynamics. The results also indicate that the estimation method works well and is a viable alternative to ARIMA and GARCH models, particularly for small data sets.  相似文献   

20.
中美微积分教材比较研究   总被引:2,自引:0,他引:2  
微积分课程的教学对高校创新型人才的培养具有重要的作用,其教材建设受到普遍关注.本文以微积分教学方法和教学理念为主线,从教材内容和案例选取、教材结构顺序以及教材表述方式等不同的角度,分析了国内外部分优秀微积分教材所具备的特色.依此为基础,以中美两部具有代表性的微积分教材为比较对象,着重对两本教材在知识点衔接、新知识的引入方式以及提出问题、分析问题的构思方法和阐述方式等具体方面进行了较细致的对比,力图从中展示出中美高等教育在教学思想和表现形式上的某些不同之处,由此得到一些有益的启示.最后,文章列举了美国微积分教材,在语言表达风格、教学案例和习题设计以及教材配套服务等诸多方面值得借鉴的经验和方法.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号