防恶意干扰的VANET双群联合定位算法

传统的无线定位方法直接应用于车辆自组织网络(VANET)时，会被窃听方利用定位信息，从而导致严重的安全隐患。为此，提出基于Bancroft方法的双群组合定位算法,用于保障车辆自组织网络中车辆定位的安全性和准确性。算法利用两个群组的智能车辆节点分别进行定位，利用两组解分别反求伪距值，如果所获得的伪距值与经过节点钟差修正后的原始伪距值基本一致，则认为这一组解为最终的定位结果，从而保证了定位的正确性。同时，双群定位的信息分散性保证了系统整体的安全性。理论分析及算法仿真表明,双群联合定位算法可使窃听方的误码率稳定在较高水平。     

Simulación de la tasa de reciclaje de productos electrónicos Un modelo de dinámica de sistemas para la red de logística inversa

Current trends in the development and innovation of information technologies and shorter life cycles of electronic products have resulted in the generation of large amounts of waste (e-waste) which can potentially cause environmental problems due to the toxicity of some of their components. The e-waste problematic has attracted the attention of governments, companies and consumers that look to identify strategies for the management and proper disposal of e-waste with the goal to protect the environment. This work uses the methodology of system dynamics to simulate how the rate of products returned by individuals and the amount of computers recovered in an open-loop reverse supply chain, varies under different scenarios. The simulated scenarios correspond to the possible combinations of five macro factors: rate of innovation and product life cycle, information available to consumers about e-waste recycling, legislation, e-waste programs structure along with diffusion and publicity efforts. The results of the simulation are relevant to identify over which factors it is convenient to intervene to increase the amount of recycled computers because this amount represents a reduction in the volume of e-waste and an enterprise opportunity to generate earnings from recycling computers.     

Leadership marketing: an exploratory study

In an era when collaboration is the key to business prosperity, the ability to develop one truly coherent and agile brand lived by its employees and delivered to external stakeholders has become extremely challenging. Unity between the internal brand and a company’s external image, when change is the only constant, has almost ceased to exist. The marketing function is frequently underemphasised at board level and its role is often devalued in leading organisational change. This paper concerns how marketing can partner with organisational leadership for a mutually beneficial exchange of skills and capabilities to be able to reinvent organisations rapidly enough to cope with shifts in the external business environment and create a sustainable future for the business. This paper explores the concept of “leadership marketing” from an interpretivist perspective which challenges the conventional view of marketing and leadership as two separate fields and offers a holistic approach for business management and brand alignment.     

An adaptive large-neighborhood search heuristic for a multi-period vehicle routing problem

This problem involves optimizing product collection and redistribution from production locations to a set of processing plants over a planning horizon. This horizon consists of several days, and the collection-redistribution is performed on a repeating daily basis. A single routing plan must be prepared for the whole horizon, taking into account the seasonal variations in the supply. We model the problem using a sequence of periods, each corresponding to a season. We propose an adaptive large-neighborhood search with several specifically designed operators and features. The results show the excellent performance of the algorithm in terms of solution quality and computational efficiency.     

The effect of continuous improvement capacity on the relationship between of corporate social performance and business performance in maritime transport in Singapore

Drawing on organisational learning theory, this study argues that shipping firms with high continuous improvement capacities have better success in transforming corporate social performance (CSP) into business performance. Survey data were collected from 223 shipping firms in Singapore and analysed using multi-sampling analysis, hierarchical regression modelling, and simple slope analysis. The results support the study’s argument and show that business performance is maximised when continuous improvement programmes targeted at CSP are carried out at a gradual pace and at regular intervals. This implies that shipping firms should adopt a dynamic, value-driven approach to improving CSP.     

System dynamics modelling and forecasting health tourism demand: the case of Russian resorts

This article presents the results of the system dynamics modelling of the regional market of health tourism in the Krasnodar region of Russia. The research was based on various indicators characterizing the supply and demand for this type of tourism for years 2006–2012. The medium-term forecast made by constructed model shows a possible decrease in number of health tourists and income of sanatorium organizations. Price competition of inexpensive foreign resorts was a key factor influencing the market of tourist services; therefore ruble devaluation to US dollar may improve the prognostic indicators.     

Stability and determinacy conditions for mixed-type functional differential equations

This paper analyzes the solution of linear mixed-type functional differential equations with either predetermined or non-predetermined variables. Conditions characterizing the existence and uniqueness of a solution are given and related to the local stability and determinacy properties of the steady state. In particular, it is shown that the relationship between the uniqueness of the solution and the stability of the steady-state is more subtle than the one that holds for ordinary differential equations, and gives rise to new dynamic configurations.     

城市土地利用碳排放系统动力学仿真研究——以武汉市为例

研究目的:从系统角度分析土地、人口、社会、经济、能源对碳排放的影响作用,并对武汉市2017—2030年不同政策情景下的土地利用碳排放进行模拟,为其低碳发展战略和低碳土地利用规划提供决策依据。研究方法:系统动力学方法。研究结果:(1)建立的城市土地利用碳排放系统动力学模型是有效的;(2)按照目前的发展趋势,武汉市的碳排放总量将保持逐年攀升的趋势;(3)经济的快速发展对武汉市土地利用碳排放量的增加具有显著的影响作用;(4)调整土地利用结构、调整产业结构以及提高能源利用效率都能够有效的减少武汉市土地利用碳排放量,其中调整土地利用结构和调整产业结构的作用效果相对来说更加明显。研究结论:转变经济增长方式、升级产业结构、调整土地利用结构和积极研发先进的低碳科学技术是武汉市低碳发展的重要途径。     

Assessing greenhouse gas emissions from electric vehicle operation in Australia using temporal vehicle charging and electricity emission characteristics

ABSTRACT

Significant interest exists in the potential for electric vehicles (EVs) to be a source of greenhouse gas (GHG) abatement. In order to establish the extent to which EVs will deliver abatement, however, a realistic understanding of the electricity and transport sector GHG emissions impacts arising from different approaches to integrating EVs into the power system is required. A key issue in this regard is the extent to which GHG emissions are a function of where and when EV charging will be enabled (or disabled) by the provision of recharging infrastructure and implementation of charging management strategies by the electricity industry. This article presents an investigation of the GHG emissions arising from electricity and gasoline consumption by plug-in hybrid EVs under a range of standard EV-power system integration scenarios. An assessment framework is presented, and GHG emissions from EV use are assessed for the New South Wales (NSW) and South Australian (SA) pools of the Australian National Electricity Market (NEM) using retrospective electricity system generation data for 2011. Results highlight that there is a range of possible outcomes depending on the integration scenario and emissions accounting approach used. This range illustrates value of a temporally explicit assessment approach in capturing the temporal alignment of electricity sector emission intensity and EV charging. Results also show the importance of a clean electricity generation mix in order for EVs to provide a GHG abatement benefit beyond what would be achieved by a hybrid (but non-plug-in) vehicle. The extent to which overnight charging in NSW is observed to produce higher emissions relative to unmanaged charging also illustrates a possible trade-off between GHG emissions and benefits for electricity industry from EV charging at times of low demand.     

CAFTA-DR Effects on FDI Inflows,Growth, and Distribution of the Workforce in Costa Rica: A System Dynamics Approach

As regional trading arrangements have spread, enlarged, and deepened over the last decades, the study of the relation between trade agreements and foreign direct investment (FDI) still presents difficulties due to the multi-dimensional character of such relationships. This article attempts to shed new light on how some of the Central American Free Trade (CAFTA) policies will impact FDI inflows on the manufacturing and agricultural sectors in Costa Rica. Specifically, we look at how the growth and distribution of the workforce is affected by the treaty. The results show that the agreement provisions will have a positive effect on FDI. From these results it is possible to estimate that in the long run, the implementation of CAFTA has a higher probability of generating the intended benefits. System dynamics modeling is used in this article.