An Efficient Algorithm for Delay Buffer Minimization

A data flow machine is said to be synchronized if for any vertex u in the underlying data flow graph, all inputs to vertex u arrive at the same time. An unsynchronized data flow machine with an acyclic underlying data flow graph can be transformed into a synchronized system by adding unit delay buffers to the system. This synchronization process can increase pipelining and throughout. Since the addition of delay buffers introduces hardware and area costs, it is desirable to insert the minimum number of delay buffers to synchronize a given data flow machine. Due to important applications in computer design, various delay buffer minimization problems have been studied by many researchers. Several optimal algorithms and heuristic algorithms have been proposed for slightly different models. In this paper, we introduce the concept of extensions of a directed acyclic graph to generalize and formalize several delay buffer minimization problems studied in the literature and present a polynomial time algorithm for computing the minimum delay buffer synchronization of a given data flow machine. Examples are provided to illustrate our algorithm and to show that our algorithm requires fewer delay buffers than previously published optimal algorithms for various models.     

论"奇异化"

什克洛夫斯基在对传统的形象思维的批判中,阐明了艺术的独立存在价值,为形式找到了自己的归宿:艺术创造中的"奇异化"描写。艺术描写本身对抗着生活的"自动化"的语言,这也就是形式获得它自主性的表现。情节编构中的"奇异化"手法:重复、穿插、突转等对情节起阻缓作用手法。     

航班延误关键影响因素及影响程度识别——基于动态排队模型的分析

通过对航班运行流程闭环不同阶段的分解分析,识别出航班延误的关键原因包括流量控制、军事活动、天气等不可控因素和安检、旅客、机械故障、机场、公共安全等可控因素。运用数理推导和实证分析,验证了飞机起飞到达服从泊松分布,航班延误符合指数分布。通过构建航班延误总动态排队模型,并基于典型机场数据的模拟仿真分析,证明各因素引发的航班延误频率高低及其影响程度并非完全一一对应。航空公司因素发生频率最高、影响最大;流量控制发生频率较高、影响大;天气因素发生频率较高、影响较大;军事活动发生频率一般,但影响大;机械故障频率较低、影响较大;机场因素频率较低、影响较小。     

Public vs. Private Offers in the Market for Lemons

We study the role of observability in bargaining with correlated values. Short‐run buyers sequentially submit offers to one seller. When previous offers are observable, bargaining is likely to end up in an impasse. In contrast, when offers are hidden, agreement is always reached, although with delay.     

高职院校实施教学质量工程的探索与实践

本文以我院实施＂教学质量工程＂为主线,以制定人才培养方案为逻辑起点,通过在校企合作、工学结合、师资队伍建设、专业建设、课程和教材建设、实践教学体系建设、共享型教学资源库建设和校园文化建设等方面所进行的探索与实践,有效地提升了人才培养质量,提高了毕业生就业工作水平,充分发挥了作为＂国家示范性高职院校＂立项建设单位服务区域经济建设和社会发展,为我国尤其是西部地区装备制造业培养更多高素质技能型人才的作用。     

高校公共体育课引入Project Adventure的探讨

心理健康、社会适应能力健康、身体健康与道德健康一起构成了人类健康的共同要素。本研究通过文献资料调研、动态性现场实验等方法,对高校体育课程中运用Project Adventure体育教育模式的可行性和必要性进行了分析,试图将目前成功应用于社会培训业的Project Adventure引入高校,通过新的整合,以此来探索高校对大学生进行心理健康教育和社会适应能力培养的新途径,表明了高校引入Project Adventure的意义和内涵,并提出了高校开设体育Project Adventure课的实施对策。     

声表面波延迟线

声表面波延迟线是在雷达和通信系统中应用非常广泛的器件.文中结合实用声表面波延迟线器件的设计实例,介绍了折叠式固定延迟线结构原理和设计计算,克服了传统延迟线受基片材料长度和器件尺寸的限制,满足了雷达、通信等电子设备中对电信号的长延迟需求;同时还讨论了为满足超高频的应用需求和增加相对带宽,所采用的谐波和倒相换能器的设计方法.     

基于时间延迟理论的预防维修模型及案例研究

本文旨在解决设备维修决策过程中预防维修检查数据缺乏情况下如何确定出合理的维修间隔期问题。首先,通过预防维修技术经济分析,提出了有关维修间隔期和总的停机时间之间关系的预防维修模型。其次,根据时间延迟维修理论,利用故障记录数据和预防维修检查数据的估计值,建立了统计模型并用来计算维修间隔期内故障次数的期望值。计算机仿真检验证明统计模型正确后,采用最大拟然法估计有关参数,这些参数包括缺陷发生率、时间延迟分布、检查出缺陷的概率等。最后是案例分析,应用估计参数和预防维修模型,计算出最佳的维修间隔期。     

全项目实战型实践教学模式在社会工作人才培养中的开发与应用

为更好提升社会工作人才职业性、专业性的素质要求,切实解决在专业人才培养过程中的实际问题,契合社会工作专业人才市场发展趋势的内在要求,从服务区域经济社会发展需求出发,贯穿于理论讲授、实习实践,毕业设计各环节,探索教师、学生和服务机构工作人员共同参与的"全项目全过程实战实践教学模式",从理论课程教学设计、实践课程教学设计、专业教师的督导制度、实习实训基地建设、社会服务项目实战等教学实践环节全面实施,明显提升学生专业视野、专业认知、专业技能等,教师的教学能力与科研水平在项目实践中得到了提高,项得到了实习机构的高度认可,打开了就业市场,赢得了就业单位的好评。     

Information Systems Project Continuation in Escalation Situations: A Real Options Model

Software project escalation has been shown to be a widespread phenomenon. With few exceptions, prior research has portrayed escalation as an irrational decision‐making process whereby additional resources are plowed into a failing project. In this article, we examine the possibility that in some cases managers escalate their commitment not because they are acting irrationally, but rather as a rational response to real options that may be embedded in a project. A project embeds real options when managers have the opportunity but not the obligation to adjust the future direction of the project in response to external or internal events. Examples include deferring the project, switching the project to serve a different purpose, changing the scale of the project, implementing it in incremental stages, abandoning the project, or using the project as a platform for future growth opportunities. Although real options can represent a substantial portion of a project's value, they rarely enter into a project's formal justification process in the traditional quantitative discounted cash‐flow‐based project valuation techniques. Using experimental data collected from managers in 123 firms, we demonstrate that managers recognize and value the presence of real options. We also assess the relative importance that managers ascribe to each type of real option, showing that growth options are more highly valued than operational options. Finally, we demonstrate that the influence of the options on project continuation decisions is largely mediated by the perceived value that they add. Implications for both theory and practice are discussed.