Flow shop scheduling with deteriorating jobs under dominating machines

This paper addresses no-wait or no-idle flow shop scheduling problems with deteriorating jobs, i.e., jobs whose processing times are an increasing function of their starting time. A simple linear deterioration function is assumed and some dominating relationships between machines can be satisfied. It is shown that for the problems to minimize makespan or weighted sum of completion time, polynomial algorithms still exist, although these problems are more complicated than the classical ones. When the objective is to minimize maximum lateness or maximum tardiness, the solutions of a classical version may not hold.     

Semi-online scheduling with “end of sequence” information

We study a variant of classical scheduling, which is called scheduling with “end of sequence” information. It is known in advance that the last job has the longest processing time. Moreover, the last job is marked, and thus it is known for every new job whether it is the final job of the sequence. We explore this model on two uniformly related machines, that is, two machines with possibly different speeds. Two objectives are considered, maximizing the minimum completion time and minimizing the maximum completion time (makespan). Let s be the speed ratio between the two machines, we consider the competitive ratios which are possible to achieve for the two problems as functions of s. We present algorithms for different values of s and lower bounds on the competitive ratio. The proposed algorithms are best possible for a wide range of values of s. For the overall competitive ratio, we show tight bounds of ϕ + 1 ≈ 2.618 for the first problem, and upper and lower bounds of 1.5 and 1.46557 for the second problem. The authors would like to dedicate this paper to the memory of our colleague and friend Yong He who passed away in August 2005 after struggling with illness. D. Ye: Research was supported in part by NSFC (10601048).     

解决农民贷款难的问题的对策与思考

深化农村金融改革过程中阶段性、结构性矛盾是农民贷款难现象产生的原因之一.农村信用环境和农业生产的风险性问题是产生农民贷款难现象的社会因素.改善农村金融服务,强化农业保险制度,加快和推进农村金融机构及结构的功能定位和调整;发展民间金融机构是解决农民贷款难的主要措施.     

关于农民专业合作经济组织发展问题

研究了农民专业合作经济组织发挥组织功能、中介功能、服务功能、教育功能和改革功能具有的重要意义以及在现实中存在的政府部门重视不够、规范化程度低和风险共担等问题;阐述了在农民专业合作发展中应遵循的原则,同时给出了推进其发展的对策是明确责任、完善政策和强化服务等措施。     

A Comparison of Ambient Casino Sound and Music: Effects on Dissociation and on Perceptions of Elapsed Time While Playing Slot Machines

This research examined the effects of a casino’s auditory character on estimates of elapsed time while gambling. More specifically, this study varied whether the sound heard while gambling was ambient casino sound alone or ambient casino sound accompanied by music. The tempo and volume of both the music and ambient sound were varied to manipulate temporal engagement and introspection. One hundred and sixty (males = 91) individuals played slot machines in groups of 5–8, after which they provided estimates of elapsed time. The findings showed that the typical ambient casino auditive environment, which characterizes the majority of gaming venues, promotes understated estimates of elapsed duration of play. In contrast, when music is introduced into the ambient casino environment, it appears to provide a cue of interval from which players can more accurately reconstruct elapsed duration of play. This is particularly the case when the tempo of the music is slow and the volume is high. Moreover, the confidence with which time estimates are held (as reflected by latency of response) is higher in an auditive environment with music than in an environment that is comprised of ambient casino sounds alone. Implications for casino management are discussed.     

高等农业院校体育俱乐部教学模式的研究

本文从终身体育的视角与俱乐部教学模式的特点出发，阐述了在农业院校中建立体育俱乐部的可行性和必要性，提出了建立农业院校体育俱乐部的理论依据和实践办法，以此改变多年来农业院校体育教育体制和模式不适应新时期体育教育的发展局面。     

基于PSR模型的中国粮食主产区农业生态安全评价及障碍因素诊断

农业生态安全作为中国粮食和生态"双安全"的重要组成部分,对实现社会可持续发展具有重要的战略意义。基于PSR模型建立农业生态安全评价指标体系,运用熵权法、综合指数法、泰尔指数对1998—2018年粮食主产区的农业生态安全进行评价,并结合障碍度模型对障碍因子进行诊断。研究表明:1998—2018年,粮食主产区农业生态安全水平呈显著上升态势,由较不安全等级向较安全等级转变,但总体仍处于较低水平;粮食主产区农业生态安全水平空间分异显著,区域发展不均衡,呈"南低北高"的空间格局;影响粮食主产区农业生态安全的主要障碍因子为化肥施用强度、农药施用强度、农膜施用强度、城镇化水平和复种指数,2018年障碍度分别为12.1%、8.2%、13.4%、17.9%、14.4%;从长远看,生态压力准则层对农业生态安全的阻碍作用持续增强,生态状态准则层和生态响应准则层对农业生态安全的阻碍作用持续减弱。在未来生态环境建设过程中,要强化农业生态环境保护监管,构建施肥、施药、施膜安全体系,切实改善农村生态环境。     

基于农业产业集群的我国农村剩余劳动力就业问题研究

解决“三农”问题关键是解决农村剩余劳力就业,然而受美国金融危机影响,农村剩余劳动力就业困难更加突出。在各种解决问题的途径中,发展农业产业集群是比较有效的。本文深入分析了农业产业集群吸纳农村剩余劳动力就业的作用机理和面临的障碍．提出了制定科学的农业集群规划、创造良好的发展环境、鼓励返乡农民就地创业等建议．以解决农村剩余劳力就业问题。     

农业投入中政府与农户的博弈分析

农业投入状况关系着农业生产和农村经济的发展。目前农业投入不足已成为制约我国整体经济发展的“瓶颈”。在是否增加农业投入的问题上,政府与农户之间存在着一种博弈关系。通过农业投入不足的现状考察,用博弈的方法阐释农业投入不足的原因,提出加大农业投入的几点对策。     

发展农业高新技术 迎接入世的机遇和挑战

加入WTO,对我国农业有一系列机遇和挑战。抓住机遇,迎接挑战的关键是发展农业高新技术。目前,我国发展农业高新技术存在着资金不足,技术体系发展不均衡,供需脱节等制约因素。因此,加强对发展农业高新技术重要性的宣传,完善高新技术的投入机制、开发机制,促进高新技术产业化,是我们的必然选择。