Predicting monthly biofuel production using a hybrid ensemble forecasting methodology

This paper proposes a hybrid ensemble forecasting methodology that integrating empirical mode decomposition (EMD), long short-term memory (LSTM) and extreme learning machine (ELM) for the monthly biofuel (a typical agriculture-related energy) production based on the principle of decomposition—reconstruction—ensemble. The proposed methodology involves four main steps: data decomposition via EMD, component reconstruction via a fine-to-coarse (FTC) method, individual prediction via LSTM and ELM algorithms, and ensemble prediction via a simple addition (ADD) method. For illustration and verification, the biofuel monthly production data of the USA is used as the our sample data, and the empirical results indicate that the proposed hybrid ensemble forecasting model statistically outperforms all considered benchmark models considered in terms of the forecasting accuracy. This indicates that the proposed hybrid ensemble forecasting methodology integrating the EMD-LSTM-ELM models based on the decomposition—reconstruction—ensemble principle has been proved to be a competitive model for the prediction of biofuel production.     

Coordination in global R&D organizations: An examination of the role of subsidiary mandate and modular product architectures in dispersed R&D organizations

International research and development (R&D) operations require a significant amount of coordination between the headquarters and the subsidiaries in order to integrate the dispersed activities in one final product. This article explores what mechanisms multinational companies (MNCs) use to coordinate their overseas R&D units. Based on a multiple case study involving nine MNCs with overseas R&D subsidiaries of varying mandates, we find that R&D sites with high technology and/or market orientation tend to be coordinated by informal mechanisms while sites with little technology and/or market orientation tend to be coordinated by formal mechanisms. Furthermore, it appears that this relationship is strongly affected by the product’s architecture: while rather complex R&D activities are conducted at the systems level and at sites with high technology orientation, less complex R&D activities are conducted at the component level at sites with low technology and market orientation. Finally, the findings suggest that modular product architectures have a coordinating effect in global R&D activities which have the power to lower firms’ overall coordination effort. The findings bear important implications for the effective coordination of MNCs’ international R&D subsidiaries.     

疫情背景下基于OBE的市场营销学混合式教学设计与实践

成果导向(OBE)的教育理念是一种以学生的学习成果为导向的教育理念,与现有疫情的契合度较高。以市场营销学课程为例,基于OBE的教学理念,以"明确学习成果—设计实现路径—评价学习成果"为主线展开混合式教学设计与实践。教学实施中结合对分课堂模式,教学实践上采用"完全线上"混合式教学模式;在教学评价上采用过程评价与结果评价结合的综合评价模式。通过教学目标、教学实施与教学评价构建循坏系统,迭代提高线上教学质量,以期最终达到预期的学习成果,打造真正的"金课",同时为后疫情时代及以后教学改革提供借鉴。     

约束满足与邻域搜索结合的混合算法及应用

总结约束满足求解技术和邻域搜索算法,分析约束满足与邻域搜索单一算法的优劣,以及两者结合的优势,提出约束满足与邻域搜索相结合的混合算法的一般框架,并以Job Shop调度优化问题为例对该算法框架进行实例说明。     

台湾证券柜台交易市场结构及其混合交易模式研究

台湾证券柜台交易市场在促进台湾中小型高科技企业的快速成长和规范非上市公开发行公司的股权报价转让等方面发挥着不可替代的重要作用。本文详细考察了台湾证券柜台交易市场上柜股票和兴柜股票的交易模式,研究表明兴柜市场实行的以分散报价、集中成交的竞争性做市商交易模式具有内在的制度优势,是适宜个人投资者为主的柜台交易市场。台湾柜台交易中心取得成功的关键在于,以满足柜台交易市场交易性需求、流动性需求、波动性需求和透明度需求为基础,通过构建合理的市场结构创造性地引入包括竞价交易机制在内、与市场功能和交易对象的风险特性相适应的混合交易模式。     

Politics and tourism promotion: Hong Kong’s myth making

By using “crisis of identity” as background, this study analyses how post-colonial Hong Kong relies on myths that are grounded in its complex, centuries-old socio-cultural political heritage to convey through tourism an identity different and separate from that of China. This qualitative inquiry, which relies on both online and printed promotional documents reinforced by primary data collected through in-depth interviews, proposes an explanation of the symbolic representation of tourism through four sequential myths. The article concludes that Hong Kong exploits its colonial past to create an identity that enhances its “local Chineseness” with a Western flavor and positions the territory to assume an increasingly hybrid identity to avoid being just another Chinese city.     

The heterogeneous green vehicle routing and scheduling problem with time-varying traffic congestion

The green vehicle routing and scheduling problem (GVRSP) aims to minimize green-house gas emissions in logistics systems through better planning of deliveries/pickups made by a fleet of vehicles. We define a new mixed integer liner programming (MIP) model which considers heterogeneous vehicles, time-varying traffic congestion, customer/vehicle time window constraints, the impact of vehicle loads on emissions, and vehicle capacity/range constraints in the GVRSP. The proposed model allows vehicles to stop on arcs, which is shown to reduce emissions up to additional 8% on simulated data. A hybrid algorithm of MIP and iterated neighborhood search is proposed to solve the problem.     

The impact of corporate governance on state-owned and non-state-owned firms efficiency in China

The purpose of this paper is to expand the literature on the corporate governance of transition economies by analyzing the relationship between corporate governance and productive efficiency in China's publicly listed manufacturing industry firms. We use the principal component analysis and the hybrid meta-frontier DEA model, separating inputs into radial inputs that change proportionally and non-radial inputs that change non-proportionally to measure the technical efficiency and technology gap ratios of publicly listed Chinese firms in different manufacturing industries during 2010–2013. The input variables are the net value of fixed assets, staff number, and the characteristics of the corporate governance system, while the output variables are gross revenue and total profit. The empirical result shows that inefficiency due to corporate governance is the main reason for lower efficiency in most manufacturing firms. For the technology gap ratio (TGR), the metal and mineral and the machinery, equipment and instrument are the two highest efficient sectors, whereas the paper and allied products sub-industry has the lowest efficiency during 2010–2013. In addition, the ratio of state-owned firms whose inefficiency is mainly caused by corporate governance to total state-owned firms is greater than that of non-state-owned firms in each year. The TGR analysis shows that the efficiency performance of non-state-owned firms is greater than state-owned firms.     

DS／FH／TH混合扩频系统抗干扰性能的计算机模拟

<正> 产品质量是产品价值的重要体现,出口产品尤其如此。随着产业革命及其技术经济的蓬勃发展,商品生产日益发达,商品供求逐步由数量型向质量型转变。因此,产品质量的社会性和质量标准的国际化问题,越来越突出地体现在国际市场激烈化的竞争实践中。面对这个现实,     

Purchasing's contribution to supply chain emission reduction

Does environmental purchasing and supplier management (EPSM) help to reduce greenhouse gas (GHG) emissions in the supply chain and, thereby, mitigate climate change? And, if so, under which conditions? Taking these two questions as a starting point, we hypothesize that heightened environmental protection efforts targeting the upstream value chain should lead to a reduction of greenhouse gas emissions in the buying companies' supply chain. We continue to delineate three contingency factors that might affect the relationship between EPSM and supply chain GHG emissions: The power of the buying firm over supply chain partners, prior experience in EPSM, and materiality of environmental supply chain management in a certain industry. We collect longitudinal data from 260 companies and analyze them using hybrid panel data analysis. We find that the increase of EPSM leads to a significant reduction of the GHG emission intensity of buying firms’ supply chains and that this reduction is stronger for companies operating in industries where emission management is more material.