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1.
志愿服务乡村是社会参与人才振兴战略的重要方式,大学生在其中承担着重要角色。“乡愁文化”和“社会理性”是大学生志愿服务乡村缘由所在;性别、年级、学校类型、了解程度和志愿组织对大学生志愿服务乡村有显著影响。大学生志愿服务的着力点在于智力支持且具有文教活动倾向性,但也存在意愿与行动脱节、认知流于表面、能动性不强、缺乏思想引领以及对小微志愿组织的支持缺位等问题。乡愁文化嵌入大学文化、引入激励机制、打造志愿组织“大家庭”、牢守宣传育人“主阵地”、强化智力支持优势、补齐理论技能短板、关爱“小微组织”成长、构建“三位一体”支撑体系等可有效优化大学生志愿服务乡村。 相似文献
2.
机械产品的设计一直注重于市场需求和产品功能的开发,随着科学和技术的发展,环境因素变得越来越重要。
提出一种基于功能一环境一结构分析( FESA)与TRIZ的机械产品创新设计方法,通过分析机械产品结构之间的功能要素
以及功能要素与环境要素的相互作用关系,确定机械产品中存在的问题。建立根原因模型图,寻找结构设计上的不足和
缺陷,利用TRIZ创新理论来实现机械产品的改进创新。通过污水处理系统的创新设计实例验证了该方法的可行性。 相似文献
3.
A. M. Abd El-Raheem 《Journal of Statistical Computation and Simulation》2019,89(16):3075-3104
The generalized half-normal (GHN) distribution and progressive type-II censoring are considered in this article for studying some statistical inferences of constant-stress accelerated life testing. The EM algorithm is considered to calculate the maximum likelihood estimates. Fisher information matrix is formed depending on the missing information law and it is utilized for structuring the asymptomatic confidence intervals. Further, interval estimation is discussed through bootstrap intervals. The Tierney and Kadane method, importance sampling procedure and Metropolis-Hastings algorithm are utilized to compute Bayesian estimates. Furthermore, predictive estimates for censored data and the related prediction intervals are obtained. We consider three optimality criteria to find out the optimal stress level. A real data set is used to illustrate the importance of GHN distribution as an alternative lifetime model for well-known distributions. Finally, a simulation study is provided with discussion. 相似文献
4.
Random effects regression mixture models are a way to classify longitudinal data (or trajectories) having possibly varying lengths. The mixture structure of the traditional random effects regression mixture model arises through the distribution of the random regression coefficients, which is assumed to be a mixture of multivariate normals. An extension of this standard model is presented that accounts for various levels of heterogeneity among the trajectories, depending on their assumed error structure. A standard likelihood ratio test is presented for testing this error structure assumption. Full details of an expectation-conditional maximization algorithm for maximum likelihood estimation are also presented. This model is used to analyze data from an infant habituation experiment, where it is desirable to assess whether infants comprise different populations in terms of their habituation time. 相似文献
5.
AbstractResource scheduling for emergency relief operations is complex as it has many constraints. However, an effective allocation and sequencing of resources are crucial for the minimization of the completion times in emergency relief operations. Despite the importance of such decisions, only a few mathematical models of emergency relief operations have been studied. This article presents a bi-objective mixed integer programming (MIP) that helps to minimize both the total weighted time of completion of the demand points and the makespan of the total emergency relief operation. A two-phase method is developed to solve the bi-objective MIP problem. Additionally, a case study of hospital network in the Melbourne metropolitan area is used to evaluate the model. The results indicate that the model can successfully support the decisions required in the optimal resource scheduling of emergency relief operations. 相似文献
6.
This study investigated the risk factors associated with the occurrence of child physical and psychological abuse in South Korea based on the ecological theory of child maltreatment. A subsample of 3‐ to 18‐year‐old children from “A Study on the Current State of Child Abuse and Neglect,” a nationally representative study on child abuse and neglect, was utilized for secondary data analysis. The sample was divided into two age groups (third graders in elementary school and below and fourth graders and above). We utilized hierarchical logistic regression for each age group separately to analyze the data. The variables at each level of the system (i.e., ontogenic development, microsystem, and exosystem) were entered into the model in sequential order. The results showed the common risk factors for both age groups are the caregiver's experience of abuse in childhood, the child's problem behavior, exposure to domestic violence, community size, and informal social control. The child's age was also significant in both groups but in the opposite direction. Social support was a significant predictor for the younger age group only, while the caregiver's level of education was significant for the older age group only. Implications for future research and practice are discussed based on the study results. 相似文献
7.
Luis Villar-Fidalgo María del Mar Espinosa Escudero Manuel Domínguez Somonte 《生产规划与管理》2019,30(8):624-638
Not only ETO (Engineering to Order), but even serial production industry should know how to deal with projects and their schedule: plant commissioning, shutdown, introducing new products and similar circumstances should be managed with adequate planning and resource allocation techniques to create a schedule useful in decision making during the execution. The current complex reality, with evolving technologies and fierce pressure to reach the market as soon as possible, pushes the project managers to use more advanced techniques than waterfall planning, such as agile or lean. It also requires them to take a holistic view and manage concurrent tasks in complex projects. The contributions of this paper are two: the proposal to control specific parallel groups of waterfall activities under uncertain environments, which can lead to iterations and reworks, as a single concurrent Activity Managed by Kanban Methods (AMKM). This activity can be subsequently embedded into traditional scheduling approaches as CPM-PERT. The second contribution is the feasibility of its application in industrial environments due to the affordability of simulation software. Two use cases are shown as evidence. It is not a disruptive proposal, but a kaizen action based on very mature technologies. Finally, it is suggested some improvements to be implemented in Project Management Software due to this ‘kaizen’ proposal. 相似文献
8.
胥文义 《重庆大学学报(社会科学版)》1996,2(4)
在分析重庆市电子信息设备制造业现状、发展的有利与不利因素以及国内外发展态势的基础上对重庆(?)子信息产业的发展提出了九条对策建议。 相似文献
9.
胡日查 《内蒙古民族大学学报(社会科学版)》2002,(5)
当前 ,社区发展已经作为一项世界性运动 ,引起了世界各国的普遍重视。近年来 ,我国的社区发展与社区建设工作虽然有了较大的发展 ,但也存在很多社区发展的制约因素 ,如今 ,我国已全面进入社会主义现代化建设的新时期 ,研究如何加快社区发展 ,改善社区成员的生产、生活条件就具有了重大的现实意义 相似文献
10.
基于GPS/GSM/GIS集成的动态车辆优化调度的研究 总被引:1,自引:0,他引:1
刘云霞 《西南交通大学学报(社会科学版)》2005,6(3):25-28
目前,GPS(全球定位系统)、GSM(数字蜂窝移动通信系统)和GIS(地理信息系统)都是成熟的商业技术。运用这些技术,再结合Dijstra最短路和贪心算法,可合理实现单配送中心、非满载送货条件下的车辆优化调度,提高配送效率。 相似文献