改进的沾滴法测量缓蚀剂预膜厚度

分析了传统沾滴法测量预膜厚度存在的问题,对原有的方法进行了改进,使用自制实验装置采用改进后的沾滴评价法测试分析了不同材质、不同管径管件的平均预膜厚度。结果表明,不同材质的管材表面吸附能力不同,导致管件平均预膜厚度相差较大,其中铜管的平均预膜厚度最大(0.05mm左右),碳钢管的平均预膜厚度最小(0.013mm左右);而管径对管件平均预膜厚度的影响很小。实验所得结果与同位素示踪法测定膜厚结果较吻合,从而说明改进后的沾滴评价法是一种室内评价管件平均预膜厚度的有效方法。     

应用型大学数学课程的研究与实践

数学是人类生活,劳动和学习中不可缺少的工具,但是我国高校的半数毕业生弄不清自己在大学中学习些高等数学课程到底有什么用,也不认为自己在将来的工作和生活中能够用到这些数学知识,而教育部在2012版课程目录指明了大学数学各个课程的开展最终是要达到能“实际应用”的这一目标,所以建设应用型大学数学课程体系就非常紧迫和必要了.本文结合在应用型人才培养这个核心目标就大学数学课程体系、教学方法、教学质量管理、实践环节建设等等进行了一些实践探索和小结.     

Updating Input–Output Tables with Benchmark Table Series

Numerous methods have been proposed to update input–output (I–O) tables. They rely on the assumption that the economic structure will not change significantly during the interpolation period. However, this assumption may not always hold, particularly for countries experiencing rapid development. This study attempts to combine forecasting with a matrix transformation technique (MTT) to provide a new perspective on updating I–O tables. Under the assumption that changes in the trend of an economic structure are statistically significant, the method extrapolates I–O tables by combining time series models with an MTT and proceeds with only the total value added during the target years. A simulation study and empirical analysis are conducted to compare the forecasting performance of the MTT to the Generalized RAS (GRAS) and Kuroda methods. The results show that the comprehensive performance of the MTT is better than the performance of the GRAS and Kuroda methods, as measured by the Standardized Total Percentage Error, Theil's U and Mean Absolute Percentage Error indices.     

Rank-based Tests for Cross-sectional Dependence in Large (N,T) Fixed Effects Panel Data Models

Most existing methods for testing cross-sectional dependence in fixed effects panel data models are actually conducting tests for cross-sectional uncorrelation, which are not robust to departures of normality of the error distributions as well as nonlinear cross-sectional dependence. To this end, we construct two rank-based tests for (static and dynamic) fixed effects panel data models, based on two very popular rank correlations, that is, Kendall's tau and Bergsma–Dassios’ τ*, respectively, and derive their asymptotic distributions under the null hypothesis. Monte Carlo simulations demonstrate applicability of these rank-based tests in large (N,T) case, and also the robustness to departures of normality of the error distributions and nonlinear cross-sectional dependence.     

The effects of slack resource of R&D professionals on firm performance: evidence from traditional manufacturing firms in an emerging economy

Abstract

As an important component of organizational human resource slack (HR slack), the slack of research-and-development (R&D) professionals has been studied by several authors. However, it remains unclear whether and how this small component of general HR slack, i.e. the slack of research-and-development professionals (RHR slack), may affect overall firm performance in an emerging economy without much R&D tradition or pro-R&D institutions. Based on two organizational theories, i.e. institutional theory and the resource-based view of the firm (RBV), we propose competing hypotheses on the relationship between RHR slack and firms’ accounting performance. We also examine whether the relationship between RHR slack and firm performance should be linear or curvilinear. Finally, we also test the relationship between RHR slack and other dimensions of firm performance. Several interesting findings have been obtained. For instance, neither the perspective based on institutional theory nor that based on RBV can fully predict all types of RHR slack-performance relationships, be these relationships linear or curvilinear.     

新零售下社区生鲜配送模式的综合评价

新零售模式下社区生鲜“最后500m”的冲刺已成为生鲜农产品快速配送的关键问题。基于目前已有的配送模式:“社区+便利店”模式、第三方配送以及众包模式,通过层次分析法从服务水平、配送成本、客户体验三个方面对三种配送模式进行量化分析,得出每种配送模式在各层次的权重。研究结果表明配送中降低配送成本是关键,减少货物赔损率、提高客户满意度才能实现有效率的配送。     

The effect of ASU 2014–08 on the use of discontinued operations to manage earnings

Review of Accounting Studies - Accounting regulations require firms to separately disclose the profits and losses from discontinued operations. These discontinued operations are typically excluded...     

Reliable Estimates of Sovereign Rating

International Advances in Economic Research -     

大豆大杂粉碎及重杂灭活工艺改造

随着国家对环保的重视,改变进口大豆大杂(豆荚、豆杆)焚烧处理的传统做法尤为重要,采用风选、粉碎等手段,区分处理轻重杂,杂质分别采用生产线高温高压和蒸汽湿热灭活法进行处理后,可充当纤维类物质掺入到成品豆粕中。根治环境污染的同时降低厂内安全风险,充分利用进口大豆秸秆类纤维物质,减少大豆损耗,以较小的投入实现经济效益和环境保护。     

浅谈分离式立交满堂支架的受力验算

分离式立交在工程实际中应用广泛,施工中对满堂支架的强度、刚度、稳定性的要求较高,本文以某工程为例,验算该支架能否满足工程施工的要求。