The resource recovery level decision for end-of-life products

Resource recovery from end-of-life (EOL) products is becoming increasingly engaged in by companies as a response to customer, consumer, government and social pressures, the electronics industry cites competitor pressures as being the main driver of EOL product take-back and recovery. Recovery can occur at three levels; i.e. product, part and material. Each of these options has economic and environmental advantages and disadvantages depending on the product type and a host of other influencing factors. The work described in this paper supports the decision as to the most favourable route from a cost and value perspective, a software model that provides such support is also described.     

Modelling end-of-life product recovery chains - a case study

European Union legislation, and existing national legislation of many European countries, mandates that manufacturers take back and recover their electronic and electrical equipment. If manufacturers are to comply with legislation, models need to be developed for these activities. Whilst infrastructural and technological deficits exist and must be addressed, so too must the organization of recovery, from a business perspective. In this paper, models of resource recovery are presented and a case study described.     

Hope the Beloved Country: Hope Levels in the New South Africa

The concept of hope seems to have attracted increased attention in popular and academic discourse in South Africa. Despite this increased focus, no empirical studies on national hope levels have been conducted in South Africa to date. This article sought to address this gap by investigating national hope levels using data taken from the 2009 wave of the Human Sciences Research Council’s nationally representative South African Social Attitudes Survey of approximately 3,300 South Africans aged 16 and older. Using a slightly modified version of the widely used Snyder Hope Scale, this study found significant geographic and social differences in citizens’ average hope levels. Differences appear to attest to the continued negative association between hope levels and membership of groups that have historically been relegated to the margins of South African society. Contrary to most current political portrayals, however, there does not appear to be a significant age cohort effect. Self-perceptions of marginalisation also appear to be related to hope. In light of the paucity of South African empirical work in this area, the paper concluded by identifying possible future research needs.     

The Euro,EU Social Democracy,and International Monetary Power: A Critique of New Constitutionalism

This article critically interrogates the principle claims of the ‘new constitutionalist’ thesis, particularly as applied to the evaluation of European monetary union (EMU). In doing so, it argues for the (continuing) efficacy of the euro as a vector for social democratic advance both at the EU and global levels. It is argued that new constitutionalism's exclusive focus on the internal and external ‘neoliberal’ constraints EMU imposes on social democracy is overdrawn. The article critically examines the internal and external dimension of EMU's alleged ‘self-limitation’. Drawing on evidence from the recent eurozone crises as well as the SGP crisis of the early to mid-2000s, it is argued that EMU's internal self-limitation has been consistently subject to successful challenge and reform through a process of ‘permanent renegotiation’. This has played out in the context of ongoing tension within EMU between alternative models of integration and decision-making. In terms of the external dimension, the article focuses on the euro's structural power and the potential this provides for global leverage. It is argued that new constitutionalism exaggerates American dominance in the global monetary domain, deflecting attention from fundamental changes in the structure and politics of international money that have contributed to the diffusion of power in a new conjuncture marked by policy conflict, contestation and uncertainty. The ‘presence’ of euro is one such structural change.

Este artículo interroga críticamente el punto principal de la tesis de los ‘nuevos constitucionalistas,’ particularmente como se aplica a la evaluación de la Unión Monetaria Europea (UEM, por su sigla en inglés). Al hacer esto, argumenta por la (continua) eficacia del euro, como un vector para el avance social democrático, tanto a nivel de la Unión Europea como global. Sostiene que el enfoque exclusivo del nuevo constitucionalismo en el ‘neoliberalismo’ interno y externo y las restricciones que la Unión monetaria europea impone a la democracia social, son una exageración. El artículo examina críticamente la dimensión interna y externa de la UEM como una supuesta ‘autolimitación.’ Partiendo de la evidencia tanto de la reciente crisis de la zona del euro, como de la crisis del SGP del principio a mediados de la década del 2000, propone que la autolimitación interna de la UEM ha estado consistentemente sujeta al reto y la reforma, a través de un proceso de ‘renegociación permanente’. Esto se materializó en el contexto de la tensión en curso dentro de la UEM entre modelos alternativos de integración y la toma de decisiones. En términos de la dimensión externa, el artículo se enfoca en el poder estructural del euro y el potencial que esto provee para el apalancamiento global. Se sostiene que el nuevo constitucionalismo exagera el domino americano en el dominio monetario, desviando la atención a los cambios fundamentales en las estructuras y políticas de la moneda internacional, que ha contribuido a la difusión del poder en una coyuntura marcada por el conflicto político, la disputa y la incertidumbre. La ‘presencia’ del euro es uno de los grandes cambios estructurales.

本文批判性地质问“新立宪主义者”的观点,尤其是当运用于欧洲货币联盟改革评价时。在此情况下,它论证了在欧盟及全球层次上都作为一种社会民主主义发展矢量的欧元的持续性效力。本文认为,新立宪主义对欧洲货币联盟施加于社会民主主义的内部和外部的“新自由主义”约束所给予的独有关注被夸大了。文章批判性地考察了欧洲货币联盟所谓“自我限制”的内部和外部维度。以最近欧元区的危机以及世纪之初稳定与增长公约的危机为据,本文提出欧洲货币联盟的内部自我限制一直受到“长久再协商”进程中的成功改革与挑战。这在欧洲货币联盟内一体化与决策的可选模式之间当前的紧张背景下已经走到头。在外部维度上,本文关注欧元区的结构性实力以及为全球影响力做准备的潜在实力。本文认为,新立宪主义夸大了全球货币领域的美国支配地位,从而忽视了在一个以政策冲突、论争和不确定性为标志的紧要关头,对权力扩散产生了促进作用的国际货币结构与政治的根本性变革。欧元的“存在”就是这样一种结构变革。

? ??? ‘??????(new constitutionalist)’ ??? ?? ??? ??????(EMU)? ?? ??? ???? ????? ??? ????? ????. ??? ??? ? ??? EU ??? ??? ???? ??????? ??? ????? ???? ??? ????. ??? ????? ????? ??????? ??????? ??? ???, ??? ????? ??? ??? ??? ??? ?? ????? ?? ????. ? ??? ?????? ????? ??????? ??, ?? ??? ????? ????. ?? ???? ??? 2000?? ??? SGP? ??? ???? ???? ??? ??? ??? ????? ???? ??? ??? ??? ??? ?? ????. ??? ?????? ??? ?? ???? ??? ??????? ?? ???? ????? ?? ??? ?????. ? ??? ??? ???? ??? ????? ???? ???? ???? ?? ???? ??? ???. ? ??? ??? ????? ????, ??? ???? ?????? ??? ???? ?? ??? ???? ????? ??? ??? ?? ??? ?? ??? ???? ?? ?????? ??? ???? ???? ??? ?? ????.     

Roman domination on strongly chordal graphs

Given real numbers b≥a>0, an (a,b)-Roman dominating function of a graph G=(V,E) is a function f:V→{0,a,b} such that every vertex v with f(v)=0 has a neighbor u with f(u)=b. An independent/connected/total (a,b)-Roman dominating function is an (a,b)-Roman dominating function f such that {v∈V:f(v)≠0} induces a subgraph without edges/that is connected/without isolated vertices. For a weight function $w{:} V\to\Bbb{R}$ , the weight of f is w(f)=∑ _v∈V w(v)f(v). The weighted (a,b)-Roman domination number $\gamma^{(a,b)}_{R}(G,w)$ is the minimum weight of an (a,b)-Roman dominating function of G. Similarly, we can define the weighted independent (a,b)-Roman domination number $\gamma^{(a,b)}_{Ri}(G,w)$ . In this paper, we first prove that for any fixed (a,b) the (a,b)-Roman domination and the total/connected/independent (a,b)-Roman domination problems are NP-complete for bipartite graphs. We also show that for any fixed (a,b) the (a,b)-Roman domination and the total/connected/weighted independent (a,b)-Roman domination problems are NP-complete for chordal graphs. We then give linear-time algorithms for the weighted (a,b)-Roman domination problem with b≥a>0, and the weighted independent (a,b)-Roman domination problem with 2a≥b≥a>0 on strongly chordal graphs with a strong elimination ordering provided.     

The positional power of nodes in digraphs

Many economic and social situations can be represented by a digraph. Both local and global methods to determine the strength or power of all the nodes in a digraph have been proposed in the literature. We propose a new method, where the power of a node is determined by both the number of its successors and the powers of its successors. Our method, called the positional power function, determines a full ranking of the nodes for any digraph. The positional power function can either be determined as the unique solution to a nonhomogeneous system of equations, or as the limit point of an iterative process. The solution can easily be obtained explicitly, which enables us to derive a number of interesting properties of the positional power function. We also consider the Copeland variant of the positional power function. Finally, we extend our method to the class of all weighted graphs.The authors like to thank two anonymous referees for their valuable comments. The first author would like to thank the Netherlands Organisation for Scientific Research (NWO) for financial support.