基于MSP430单片机的流量显示表硬件CPU设计

随着计算机的发展,工业自动化水平的提高,在工程中流量显示表已得到了广泛的使用。显示仪表精确度的高低,直接影响着企业的经济效益。在我国现有经济水平下,使用单片机开发的流量显示表,在工程中是非常适用的。该表是用MSP430F135为主芯片,并辅以其他的外围模块构成的具有串行通讯功能,满足流量检测显示的嵌入式最小系统。     

基于CFD的羧化釜搅拌改造设计

通过改变搅拌桨形状,对8立方液固两相体系的羧化釜进行了搅拌流场、固含率进行模拟,从流体力学角度对羧化釜进行了优化。将模拟优化结果用于实际工业生产中,结果表明:计算流体力学(CFD)模拟优化后的羧化釜能够改善釜内流体流动情况,从而对反应产生影响,使原料转化率提高了5.6个百分点。     

计及外部性的储能系统价值测算及经济性评估

以应用在电力系统中的电储能系统为研究对象,以外部性理论为基础,构建了计及外部性的储能系统经济性测算模型,并以储能系统接入光伏电站为例,采用贴现现金流分析方法,预估储能投资成本和收益,分别从投资者角度和社会整体效益角度,来研究储能系统应用在可再生能源发电侧的经济性,并进行了盈亏平衡分析。通过盈亏平衡曲线分析了储能盈亏平衡情景,经济性分析结果显示储能系统的外部性收益占年收益比例较大。     

基于云计算技术的铁路调度集中系统架构设计研究

为使铁路调度集中系统更好地满足运输组织需求,提升运输组织效率,阐述我国铁路调度集中系统运用现状,针对存在的系统功能区域化割裂、系统部署灵活性较低、系统建设和运用成本高等问题,结合铁路调度集中系统运用特点,提出基于云计算技术的铁路调度集中系统架构方案,将铁路调度集中系统部署在由云平台资源层、云平台服务层、云平台用户与接口层组成的云平台上,按需分配系统资源并动态扩充系统边界,提升系统资源利用率,提高业务协调性和计划编制的统一性,减轻运输人员的劳动强度,保障铁路运输生产的安全稳定。     

基于生态系统服务功能的森林社会效益价值评估——以云南省森林资源为例

森林除了具有经济价值和生态价值外,还具有基于生态系统服务功能所产生的社会效益价值。论文以云南省森林资源为例,采用房地产评估中常用的假设开发法为主要评估方法,结合森林资源所反映的社会效益价值增长特征,运用企业自由现金流量折现模型中的两阶段现金流折现模型,通过构建模型体系,分别从直接社会效益和间接社会效益两个维度对云南省森林资源的社会效益价值进行评估。其中,直接社会效益包括就业价值和景观游憩价值,间接社会效益包括科教价值、历史价值及文化价值,通过模糊综合评判计算各组成部分的不同影响权重得出直接和间接社会效益模型,以多元回归的方法构建森林生态总体社会效益价值模型并计算云南省森林社会效益价值。同时,将各部分价值结果分别与云南省第三产业GDP、人均GDP及云南省GDP进行对比分析,进而对云南省森林社会效益价值现有情况进行评价,并对今后的森林资源开发提出相关建议。     

Collaborative delay management towards demand-capacity balancing within User Driven Prioritisation Process

The concept of User Driven Prioritisation Process (UDPP) was introduced to give Airspace Users (AUs) more flexibility under demand-capacity imbalance. This paper presents two UDPP-DCB models, built on the UDPP principle, using the Selective Flight Protection (SFP) approach to minimize the total delay cost. AUs are enabled to adapt their operations in a more cost-efficient way in the presence of capacity constraints in airspace, optimizing their flights to keep the priorities track. Then, ATFM integrates the AUs’ decision to reassign the time slots and the preferred rerouting trajectories. Results suggest that the delay cost for AUs can be largely reduced through applying the UDPP-DCB models proposed in this paper, while allowing rerouting proves effective in reducing the system delay cost.     

Disappearing investment-cash flow sensitivities: Earnings have not become a worse proxy for cash flow

According to a recent conjecture in the literature, earnings have become a poorer proxy for cash flow from operations over time. We find that since 1988, when cash flow statements started to be consistently reported in Compustat, the cash effectiveness of earnings has actually increased for a large sample of US manufacturing firms. This occurs despite the introduction of fair value accounting and increasing accounting accruals during the last three decades. Also contrary to the conjecture, using more comprehensive measures of cash flow does not restore the investment-cash flow sensitivity, which continues to be around 0.05 in more recent periods.     

The effects of board structure on corporate performance: Evidence from East African frontier markets

The effectiveness of the well-known corporate governance practices may not be universal due to fundamental differences in the environments under which firms operate. By using hand-collected data from all the non-financial firms listed on the unexplored East African frontier markets (i.e., Kenya, Tanzania and Uganda), we examine the effect of board characteristics on the performance of firms. Our results show that board size has a negative and significant effect on firm performance. The presences of foreigners and civil servants on the board play positive roles on financial performance, where the agency and resource dependence theories apply. Further, we find that board members with higher education also contribute to firm performance. These findings still hold when we consider the 2008–2009 financial crisis period. Overall, we show that in a business climate where ownership is largely dominated by few shareholders, the conventional governance mechanisms do not work effectively.     

How do empowered employees engage in voice behaviors? A moderated mediation model based on work-related flow and supervisors’ emotional expression spin

The study examines the impact of empowerment on promotive and prohibitive voice behaviors in a moderated mediation model, suggesting work-related flow as a mediator and supervisors’ emotional expression spin as a moderator for hospitality employees based on affective event theory. The proposed model was tested using longitudinal matched data collected from 142 restaurant employees and their supervisors across multiple time stages in China. Analysis found that work-related flow mediated the relationships between empowerment and employee promotive and prohibitive voice behaviors, and supervisor emotional expression spin moderated these mediation links. The theoretical and practical implications of these findings for hospitality researchers and industry practitioners are discussed.     

Intermediate units in multinational corporations: A resource dependency view on coordinative versus entrepreneurial roles

Due to the dispersion of headquarters’ activities across organizational and geographical boundaries, intermediate units (IUs) are emerging as a key actor of international business. IUs are intermediate structural layers between headquarters (HQ) and local subsidiaries with specific HQ responsibilities. Our study relies on original data of 67 IUs and, taking on a Resource Dependence approach, explores empirically the two HQ roles attributed to IUs: coordinative versus entrepreneurial. According to our results, the main differences between both roles relate to external network embeddedness, internal network position and autonomy. We argue that these differences arise from the dominant sources of power in each role. These findings have signi?cant relevance for theory development and managerial practice as we provide a starting point for understanding the dispersion of complex HQ systems as well as how those systems are discharged and add value.