掘进工作面临时支护技术的发展与应用

目前现代化矿井存在掘、支时间比例失调的矛盾,临时支护劳动强度大,效率低,支护速度影响掘进速度,分析了目前国内外掘进工作面临时支护技术的发展与应用以及存在的问题,提出今后掘进工作面临时支护技术的发展方向。     

Policy aspects of driver support systems implementation: results of an international Delphi study

Driver support systems are generally assumed to contribute to public traffic goals. However, much uncertainty exists about their future: technology development, market introduction and impacts on driver and traffic behaviour. An international Delphi study, collecting expert opinions on these issues, is describe this paper. In three rounds opinions were collected from 50 experts from USA, Japan and Europe. The article focuses on market introduction, driver behaviour, general barriers and policy options.     

Control-based optimization approach for aircraft scheduling in a terminal area with alternative arrival routes

This paper presents an optimization approach for dynamically scheduling aircraft operations and supporting air traffic controllers in both determining and implementing operationally feasible landing and departure times at an airport. The mixed integer linear programming model proposed incorporates air traffic control infrastructure in terms of route network, introduces the concept of alternative approach routes and is designed to generate an output that can be converted into effective advisories for executable flight commands. It shows reasonable computational times for obtaining the optimal solution and delay reductions of up to 35% with practical size instances from Sao Paulo/Guarulhos International Airport.     

Hazmat facility location and routing analysis with explicit consideration of equity using the Gini coefficient

This paper develops a model to analyze facility location and routing decisions in the context of hazardous materials transportation. A novel aspect of this model is the explicit consideration of equity using the Gini coefficient, an established computation to evaluate equity. To solve the model, we develop a method that combines Lagrangean relaxation with column generation and illustrate that method using a realistic case study. We present a case study of hazardous material railway transportation with consideration of social horizontal equity categorizing the population by household income.     

PIC16F877单片机与PC机的串行通信

介绍了PIC16F877单片机与PC机实现串行通信的一种方法,并给出了硬件接口电路及通信源程序。     

Marketing’s role in multi-stakeholder engagement

In 2019 the CEOs of more than 180 of the largest U.S. firms signed a statement of corporate purpose indicating that corporations are responsible for providing economic benefits to all stakeholders, not just shareholders. Although stakeholder theory states that there are several stakeholders (internal and external) whose continuing participation affects a firm’s sustainability and long-term profitability, the marketing literature has focused primarily on customer engagement. This research argues for a broadened focus by marketing scholars and introduces a stakeholder engagement framework based on a triangulation approach including a systematic review of marketing research from a stakeholder perspective, the results of a survey of 254 editorial review board members from top marketing journals, and business case examples. The framework identifies three dimensions of firms’ stakeholder engagement strategies (stakeholder recognition, support, and dialogue) linked to stakeholder responses (stakeholder contribution to the firm or retaliation) that ultimately influence firm performance (financial, reputation, and risk). Two core propositions of multi-stakeholder engagement provide a foundation for a detailed future research agenda for marketing.     

基于局部极值共生模式和能量分析的烟雾检测

针对烟雾稀薄的场景提出了一种新颖且具有鲁棒性的视频烟雾检测方法,该方法主要由预处理、特征提取和图像分类三个阶段组成。在预处理阶段,使用背景差分算法提取视频帧的运动前景区域,并采用HSV颜色空间作用于运动前景区域识别烟雾像素;然后使用局部极值共生模式(Local Extrema Co-occurrence Pattern,LECoP）计算纹理特征和使用烟雾能量分析计算能量特征;最后,将特征矢量融合训练支持向量机（Support Vector Machine,SVM）用于识别烟雾。实验结果表明该方法能有效检测出烟雾。     

自贡旅游产业优化发展的现状、主要问题及对策

实现由旅游资源大市向旅游经济强市跨越的奋斗目标,是自贡市经济社会发展面临的一个现实课题。文章基于自贡旅游产业发展的目前状况,提出了将自贡旅游产业培育成国民经济战略性支柱产业,强化对自贡旅游产业的金融支撑,以及有机整合川南旅游资源等政策建议,以促进自贡旅游产业优化、配套发展。     

Performance improvement decision aid systems (PIDAS) in retailing organizations using data envelopment analysis

This paper investigates the usefulness of Data Envelopment Analysis (DEA) models to aid decision making in multi-level retail organizations. It is argued that market efficiency is a key performance measurement dimension in retail organizations. The paper proposes three variants of market efficency that correspond to different tiers of management in a multi-level setting. The disentanglement of market efficiency will lead to the development of the Performance Improvement Decision Aid System (PIDAS) which seeks to classify units on clusters of different performance profile. The method is illustrated using data from a restaurant chain in the UK.     

Global agricultural trade liberalization: Is Sub-Saharan Africa a gainer or loser?

This paper analyzes the potential impact of agricultural trade liberalization on Sub-Saharan Africa. We used the Agricultural Trade and Policy Simulation Model to estimate the potential effects of agricultural trade liberalization, mainly in the US and EU, on the world-market prices of agricultural commodities. We then used the estimated price changes to assess the impact of these reforms on net-food importers as well as other Sub-Saharan African countries that enjoy preferential trade agreements with the EU and US. The results indicate that the world market prices of all commodities imported by Sub-Saharan Africa are expected to rise while the prices of the key export commodities of the region would either decline or remain unchanged. Given that the prices of major food commodities are expected to rise, net-food-importing countries will experience increasing import bill, thus leading to welfare loss. Major Sub-Saharan Africa sugar exporters who are beneficiaries of preferential agreements such as the EU sugar protocol and US AGOA initiative will become losers as preferences erode due to global liberalization. Thus, the region is expected to generally become a net loser from the current WTO reform modalities.