关于汽车追尾冲击模型的维修策略

讨论了关于汽车追尾的冲击模型的可修系统．在系统不能修复如新的条件下,假定汽车运行时间构成随机递减的几何过程,逐次追尾后的维修时间构成随机递增的几何过程．分别考虑汽车按比例保修和免费保修条件下,以汽车追尾次数N为策略,以车主在汽车长期运行单位时间内的期望费用为目标函数,导出目标函数的解析表达式P1（N）与P2（N）．最后,通过实例分析,求出最优策略N＊,使得车主在汽车长期运行单位时间内的期望费用最小．     

中短途汽车客运问题博弈分析

汽车客运尤其是中短途汽车客运在人们的现代生活中发挥重要的作用,它在拥有众多长处的同时也存在着许多问题和不足.从经济博弈论的角度,对客运车主和交通管理部门的行为进行分析,从而说明违规运营现象存在的原因并提出相应的解决措施.     

一种航空客机选型的随机多属性决策方法

为解决航空公司客机选型决策中,需要使用的旅客需求信息为随机信息的问题,本文研究了考虑随机信息的航空客机选型多属性决策方法.首先在分析飞机选型工作流程的基础上,建立了航空客机选型评价指标体系;然后针对指标信息中既有数值信息又有随机信息的特点,给出了一种航空客机选型的随机多属性决策方法;最后通过一个算例说明了本文给出方法的可行性和有效性.相关原理和方法可以扩展应用到新能源汽车服务网络方案选择、移动信息服务开发项目选择等决策问题.     

基于政府干预的报废汽车回收博弈模型

为分析政府干预如何影响当前报废汽车市场的回收效率,分别建立了基于政府补贴、政府规范的博弈模型,并对比分析了补贴前后、规范前后正规回收拆解企业和非正规回收拆解企业的决策。研究结果表明,两种策略对回收市场都有显著的正向导向作用,且受车主对回收价格的敏感度和市场主体之间竞争程度的影响。但当前市场环境下,相较于规范,补贴更有利于回收市场的健康发展。最后,通过数值仿真探讨不同补贴和规范政策对废旧汽车回收率的影响,为政府和汽车回收拆解企业提供有意义的决策依据。     

维修优先于保养的多状态系统的可用度分析

主要研究一类常见的可修多状态退化系统模型,且针对系统的可靠性优化和服务台的有效利用,提出了维修优于保养的的系统优化策略.假定系统随在退化过程中,选择不完全预防性保养,当系统发生故障时,服务台停止保养而转向维修故障.在整个退化、保养、维修等过程中,根据模型实际假设和状态转移图,结合广义马尔可夫过程理论,建立状态概率转移微分方程组,根据可用度的定义,利用极限思想得到稳态可用度的计算方式和结果.最后利用数值算例得到维修优先于保养的多状态系统的稳态可靠度,以及保养率和维修率对可用度的影响,从而体现维修优于保养的优化策略对可靠性设计具有重要意义和实际价值.     

三种类型汽车的能耗和使用成本的建模研究

本文对电动,传统,混合动力三种类型汽车的能耗和使用成本问题进行了建模、求解及分析．首先定义了电动汽车的能量利用率ηE。根据能量守恒将所有电量转换成汽油消耗量,而传统车型则直接反映到汽油的消耗上,混合动力汽车则综合电动汽车和传统汽车的能耗模型,从而统一能耗水平评价标准．这样,我们就得到了三种不同类型车的能耗模型再进行模型求解以此来分析比较三种类型车哪一种节能效果好．对电动汽车来说,使用成本主要包括驾驶维护成本、报废处理成本,而对传统汽车来说,使用成本主要包括驾驶维护成本、报废处理成本、环境成本和其他成本,混合动力汽车则结合二者使用成本．因此,根据不同车型使用成本类型建立相应的数学模型,按照建立的公式,可以得到电动汽车的使用成本LCC1、传统汽车的使用成本LCC2和混合动力汽车的使用成本LCC3,从而进行模型求解．     

对农村初中生数学成长记录袋作用的认识与实践

课程改革实施以来,许多教师对成长记录袋评价进行了不同程度的理论研究与实践探索,创建和使用了多种多样的成长记录袋,成为当前中小学教育评价改革的新亮点.但有些成长记录袋的设计流于形式,使用后的效果并不理想,对学生没有太大的促进作用.笔者对数学成长记录袋的使用情况做了一个调查,发现主要问题是对成长记录袋的基本原理与使用要求还存在模糊甚至错误的认识,致使成长记录袋评价在实际应用中出现了一些偏差,主要有:1.从形式上来看,将成长记录袋规定得太细,几乎千篇一律,每项内容都是预先设计好的,学生根本就没有可发挥的余地,没有自主权…     

“菱形”的教学案例述评——分工合作观课汇集

日常的课堂教学情况的记述 ,也能成为一个好的教学案例 ,如果你能搜集到有独特视角的较精彩的课堂信息 (教师的 ,还有学生的 ,特别是关于学生思维活动状态的内外部表现的信息等 )的话 .因为考虑到课堂上的信息面宽量大流动又快 ,一个人的两只眼睛两个耳朵一支笔是决计应付不过来的 ,我们想到了分工合作观课的做法 .本篇就是南海人的一次实践的部分反映 .他们把 1 0余位听课老师分为如下 5组 :A组任务 ,课堂教学的结构分析与课堂练习分析 ;B组 ,3人交叉分工 ,力求详细地记录主要的启发问句 (注意 :点评中对问句的记录分析 ,就比往常仔细深入 !) ;C组 ,记录分析几个较典型阶段的师生互动过程 ;D组 ,分坐四周 ,每人观察记录邻近 4名学生的课堂表现、状态 ;E组 ,课后问卷调研 ,访谈测试等 .郑老师的点评 ,只汇集反映了其中的小部分情况 .我们认为 ,为了及时了解一堂课的教学效果 ,不能单凭经验印象 .而要较客观的做好教学评价工作 ,把一些新手段 (诸如分工观课 ;观察研究学生状态 ;课后对学生的调研、访谈测试等 )引进到观课评课中来 ,是十分必要的 .这也是本篇设计的一个方面的意义 !     

到点式服务模式电动汽车电池需求预测

针对电动汽车充电难这一现状,分析现有的电动汽车充换电模式特点,结合电动汽车服务"通用化、智能化"趋势,提出了换电站到点式服务模式.分析到点式服务模式下用户的需求分布特点,建立灰色预测模型对电动汽车保养量进行预测,利用汽车保有量与电池关系来预测电池需求量,作为换电站电池配依据.最后,选取北京的相关数据进行分析,验证了模型的可行性与有效性.     

自卸汽车装卸粘性土时粘附规律的统计分析

本文通过对自卸汽车的现场施工进行抽样调查，采用数理统计、灰色关联分析和模糊分析等方法，分析了自卸汽车粘土部位的变化规律和自卸汽车粘附积土的影响因素对粘土量的影响，揭示了自卸汽车的粘土规律，为通过工程仿生途径解决自卸汽车粘附积土问题创造了条件。     

Agile infrastructure design for garment industry

The Information Economics and its platform can input the vigor into manufacturing industry, i.e., garment industry, help to increase its ability for good return, promote the level of technology and management of Garments from a labor-intensive industry, and move it to the accurate management. The platform is designed as Comprehensive Information Platform by our research team. This paper is a general report series of papers the design of Agile Infrastructure for Collaborative Manufacturing and Agile Supply Chain. The key enabled technologies in the platform includes agile infrastructure and its application, business resources planning in manufacturing system, the design of data access model, optimal strategy for production planning, the dynamic load balance scheduling model, the intrusion detection technology and intelligent communication strategy. All of them are elaborated in turn. The paper tries to introduce the research of Agile Infrastructure and its key technologies, showing how well they work in some traditional manual industries.     

开放授权协议在云学习中的应用研究

云学习如今已经成为现代教育技术发展的一个重要方向,一个依托于云计算技术而设计的网络教学平台将成为网络教学顺利开展的重要基础.在整个网络教学平台中,账户管理是一个网络平台正常运行的基础,这其中又以用户注册和登录最为重要.所介绍的开放授权协议即针对传统账户管理模式的不便提供了新的思路文章中首先简要介绍了OpenID与OAuth两种账户管理模式的发展历程,并对这两种用户管理模式进行比较,然后重.点介绍开放授权协议模式下网络平台搭建的思路和方式.最后,以一个微博教学平台为例,介绍了基于开放授权协议的微博教学平台搭建的过程.     

Lag synchronization of hyperchaos with application to secure communications

In this paper, hyperchaotic lag synchronization is restated as a nonlinear and lag-in-time observer design issue. This approach leads to a systematic tool, which guarantees the lag synchronization of a wide class of chaotic or hyperchaotic systems via a scalar signal. By exploiting this result, we propose a hyperchaos-based cryptosystem scheme that combines the conventional cryptographic methods and the lag synchronization of chaotic circuits. The computer simulation results show that the lag synchronization scheme and the cryptosystem proposed in this paper are both feasible.     

Synchronization of generalized Henon map via backstepping design

This paper proposes a backstepping method to resolve the synchronization of discrete-time chaotic systems. The proposed scheme offers systematic design method for the synchronization of a class of discrete-time hyper-chaotic systems, which implies much complicated high-order chaotic systems can be used to improve the security in chaos communications. A well-known chaotic systems: generalized Henon map is considered as illustrative example to demonstrate the general applicability of backstepping design. Numerical simulations verify the effectiveness of the approach.     

Static binary analysis of mobile applications for the android platform,according to the requirements of information security

An approach is presented for solving the problem of automatically analyzing mobile applications for the Android platform in light of information security requirements when no source code is available.     

Finite-time synchronization of master-slave neural networks with time-delays and discontinuous activations

This paper deals with the finite-time synchronization issue of time-varying delayed neural networks (DNNs) with discontinuous activations. Based on master-slave concept, several sufficient conditions are given to guarantee the finite-time synchronization of discontinuous DNNs. In order to control the synchronization error to converge zero in a finite time, we design three classes of novel switching state-feedback controllers which involve time-delays and discontinuous factors. The analysis in this paper employs the extended differential inclusion theory, the famous finite-time stability theorem, inequality techniques and generalized Lyapunov approach. Moreover, the upper bounds of the settling time of synchronization are estimated. Finally, the validity of proposed design method and theoretical results are illustrated by numerical examples.     

Adaptive synchronization of a modified and uncertain chaotic Van der Pol-Duffing oscillator based on parameter identification

This paper considers the problem of adaptive synchronization and parameter identification of an uncertain chaotic oscillator. Using recent results on adaptive control, we design a controller which enables both the synchronization of two unidirectionally coupled modified Van der Pol-Duffing oscillators and the estimation of unknown parameters of the drive oscillator.     

Synchronization and anti-synchronization of chaotic oscillators under input saturation

This paper addresses the design of simple state feedback controllers for synchronization and anti-synchronization of chaotic oscillators under input saturation and disturbance. By employing sector condition, linear matrix inequality (LMI)-based sufficient conditions are derived to design (global or local) controllers for chaos synchronization. The proposed local synchronization strategy guarantees a region of stability in terms of difference between states of the master–slave systems. This region of stability can be enlarged by means of an LMI-based optimization algorithm, through which asymptotic synchronization of chaotic oscillators can be ensured for a large difference in their initial conditions. Further, a novel LMI-based robust control strategy is developed, for local synchronization of input-constrained chaotic oscillators, by providing an upper bound on synchronization error in terms of disturbance and initial conditions of chaotic systems. Moreover, the proposed robust state feedback control methodology is modified to provide an inaugural treatment for robust anti-synchronization of chaotic systems under input saturation and disturbance. The results of the proposed methodologies are verified through numerical simulations for synchronization and anti-synchronization of the master–slave chaotic Chua’s circuits under input saturation.     

Stability criterion for synchronization of linearly coupled unified chaotic systems

This paper investigates the synchronization of two linearly coupled unified chaotic systems. A new stability criterion for asymptotic synchronization is attained using the Lyapunov stability theory and linear matrix inequality (LMI) approach. A numerical example is given to illuminate the design procedure and advantage of the result derived.