宽中央隔离带路口交通组织优化设计

在城市高架桥的建设中，桥下的平面交叉口空间受高架桥体的影响，很多属于宽中央隔离带的路口，两个路口中间部分按照路段进行渠化，车流互相影响严重。为了解决这类问题，以石家庄市北二环和红星街的平面交叉口为例，对宽中央隔离带路口的交通组织进行了研究。主要从路口渠化和配时上提出了新的交通组织方案，最后利用VISSIM仿真软件对方案进行评价。仿真结果表明：提出的新方案可有效减少延误，提高交叉口运行效率。     

频偏条件下基于循环平稳的定时估计算法

研究了利用信号的循环平稳统计特性提取定时误差的估计算法,由于性能的优良是建立在大量统计信息的基础上,因而所需的观测时间长度较大,同时算法受频偏的影响也随观测时间长度的增大而增大。针对该特点,研究了频偏对算法性能的影响及存在频偏环境下算法中参数的选择。仿真结果表明,频偏对该类算法的影响不可忽略,尤其是在观测时间长度较大的情况下。实用中应结合具体频偏大小,合理选择参数取值。     

相对时延对空时/时频调制系统性能的影响

在介绍空时/时频调制(ST-TFSK)系统原理的基础上,该文推导了在接收端已知相对时延条件下的非相干ML判决度量,讨论了在接收端未知相对时延条件下信噪比与系统误码率性能的关系,并将其结果与空时/频移键控(ST-FSK)系统的情形相比较。理论分析和仿真结果表明:低信噪比弱化了相对归一时延对ST-TFSK系统可靠性的影响;ST-TFSK系统对相对归一时延的敏感性弱于ST-4FSK系统。     

政治因素与中国早期现代化的延误

中国早期现代化作为后发、外源、追赶性质的现代化在启动以后,非经济因素尤其是政治因素的作用要大于经济因素的作用,特别是需要一个强固有效且以现代化为明确取向的政权,需要核心统治层的积极推动,中国早期现代化过程中并不具备这些,加之历史继承的传统政治的严重束缚,因此一再失去机遇。     

多机场地面等待问题中的损失系数研究

以航空公司和乘客的损失程度作度量,将飞机起飞时刻的累计综合损失作为多机场地面等待模型中的损失系数,能更为有效地反映了地面等待的损失程度,强调了延迟时间对损失程度的累计效应和非线性特征。通过参数设置调节各损失因素所占的比例,将影响因子的重要性体现在损失系数的大小中,从而使损失系数可以适应不同的应用环境。     

The reputational benefits of instructing information: The first test of the revised model of reputation repair

Situational Crisis Communication Theory (SCCT) prescribes crisis response strategies for organizations facing crisis. A meta-analysis of SCCT suggests using the prescribed responses has, at most, a small effect on reputation, while a few studies have shown that the base crisis responses (instructing information and adjusting information) may have a larger effect on reputation. This experiment compares the effects of SCCT’s prescribed responses, instructing information, and adjusting information on reputation in an experiment with 989 participants recruited from mTurk. It finds that instructing information has a very large effect on reputation, while adjusting information has a small but significant effect on reputation. In this sample, SCCT’s prescribed response strategies have no significant effect on reputation. The experiment proposes the revised model of reputation repair (REMREP) as a tool for understanding how crisis influences reputation. The model incorporates virtuousness and offensiveness, which demonstrates the importance of organizational virtuousness in handling a crisis. Implications for theory and practitioners are discussed.     

时滞微分方程边值问题正解的存在性

利用Avery-Peterson不动点定理,讨论了具有p-Laplacian算子时滞微分方程边值问题3个正解的存在性.     

航班延误的应对机理及制度形塑

航班延误是困扰民航运输领域的长久难题。航班延误补救困境产生的原因主要包括国有航空公司未转变垄断经营者的角色、航空公司与旅客之间的信息不对称以及延误信息未及时传递给旅客。其应对机理在于,以旅客权利为本位,构建航空公司和旅客之间互动式的多元和谐关怀。航班延误的制度形塑具体包括规范航班延误的补偿标准、引入航班延误险的责任分担机制、完善综合应对措施以及引入权威的裁决机构和纠纷速裁机制。     

MRO inventory reduction—challenges and management: a case study of the Tennessee Valley Authority

Emphasis on maintenance, repair, and operations inventory (or MRO inventory) can lead to improved inventory control, reduced operational costs, enhanced productivity, and increased cost accounting accuracy. To review the benefits of MRO inventory reduction, as well as highlight the management challenges associated with the process, a case study of the Tennessee Valley Authority (TVA) is presented. TVA is a not-for-profit electric power generation entity. TVA standardised inventory policies and procedures. Their comprehensive five-year plan included employee training, changes in organisational structure and strategy, reduced MRO inventories and the establishment of new growth drivers. Net inventory reductions of $47 million were realised. Suggestions for future MRO inventory reductions as well as replication of the management involvement and improvement process in other organisations are included.