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This paper reviews the opportunities available for food businesses to encourage consumers to eat healthier and more nutritious diets, to invest in more sustainable manufacturing and distribution systems and to develop procurement systems based on more sustainable forms of agriculture. The important factors in developing more sustainable supply chains are identified as the type of supply chain involved and the individual business attitude to extending responsibility for product quality into social and environmental performance within their own supply chains. Interpersonal trust and working to standards are both important to build more sustainable local and many conserved food supply chains, but inadequate to transform mainstream agriculture and raw material supplies to the manufactured and commodity food markets. Cooperation among food manufacturers, retailers, NGOs, governmental and farmers' organizations is vital in order to raise standards for some supply chains and to enable farmers to adopt more sustainable agricultural practices.  相似文献   

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The investigation of very complex dynamical systems like the human metabolism requires the comprehension of important subsystems. The present paper deals with energy supply chains as subsystems of the metabolism on the molecular, cellular, and individual levels. We form a mathematical model of ordinary differential equations and we show fundamental properties by Fourier techniques. The results are supported by a transition from a system of ordinary differential equations to a partial differential equation, namely, a transport equation. In particular, the behavior of supply chains with dominant pull components is discussed. A special focus lies on the role of buffer compartments.  相似文献   

5.
Flexible Services and Manufacturing Journal - We explore the value of information sharing for smoothing the dynamics of supply chains when some echelons do not collaborate. To this end, we study...  相似文献   

6.
Bacterial polyesters such as polyhydroxybutyrate (PHB) or polyhydroxyalkanoates (PHAs) have to pass the following requirements to be accepted on a large scale: (i) they have to fulfil an urgent market need: (ii) they require that new and efficient composting systems are installed in urban areas; (iii) they have to complete with the present plastics as far as quality and processing performance are concerned; (iv) they have to meet the requirement for the registration as food packages; and (v) they have to meet competitive price limits. (i) Some 30% of the plastics in the municipal waste originates from goods which are less than 1 year in use and tend to be heavily soiled by food and feed residues. This part is difficult and expensive to dispose of. Biodegradable alternatives could replace a large part of it. The waste could be diverted from landfills and incineration to composting sites near the end user. The savings in costs and frustrations are the source of a pressing demand for biopolymers, especially for producing goods which do not demand longevity and which are likely to end up soiled with organic matters. (ii) Composting infrastructures exist in rural areas. In urban areas new systems for collecting and composting ‘garden and kitchen wastes’ are being installed for reducing landfill problems, especially in Austria, Denmark, Germany and the Netherlands. These installations give biopolymers a competitive edge in the disposal discussion. (iii) Bacterial polyesters meet various quality and processing performances. They are water-resistant, and goods made of the polyesters are water-tight. The material can be processed by injection and by blow moulding. However, the esters are not flexible enough for forming films or foils. They also tend to become brittle and to lose their vapour barrier properties. It is expected that these limits will be overcome by improving blend formulations. (iv) Bacterial polyesters are not yet allowed for use as food package material. Since the esters represent a novel product, the procedure for the registration poses serious, but no insoluble problems. They require long and costly tests. There are no indications that bacterial polyesters would not attain the requirements. However, they are not expected to serve as food packages in the near future. (v) The present prices for bacterial polyesters are far too high to be accepted on a large scale by the processing and packaging industry. Costs are high mainly because of the raw material prices and to the small-scale production units. They can be lowered to accepted levels by investing in larger units in countries where inexpensive raw materials are available. Thus they will be able to meet the price limits. Since bacterial polyesters increasingly meet the requirements for the penetration of a mass market and since more and more consumers accept composting as an environmentally sound way of recycling organic materials, the polyesters are expected to penetrate a significant part of the short-lived and contaminated plastic products markets by the turn of the century.  相似文献   

7.
Recent studies demonstrate positive density-dependent feedbacks between animal populations and their resource supply that result in increased individual fitness at high densities. Such feedbacks occur in both terrestrial and aquatic organisms not showing strong social organization. A number of different mechanisms are involved. Detecting positive feedbacks in natural populations may not be possible from simple correlations between resource abundance and animal population density in space or time, but experimental manipulation of resource supply or animal density can reveal their presence. Positive feedbacks may result in higher equilibrium densities of animal populations, alter the density range over which intraspecific competition is detectable, and offer a resource-based explanation for the evolution of gregariousness and social organization.  相似文献   

8.
Raw materials costs form an increasingly significant proportion of the total costs of renewable energy technologies that must be adopted at unprecedented rates to combat climate change. As the affordable deployment of these technologies grows vulnerable to materials price changes, effective strategies must be identified to mitigate the risk of higher input costs faced by manufacturers. To better understand potential threats to deployment, a market modeling approach was developed to quantify economic risk factors including material demand, substitutability, recycling, mining productivity, resource quality, and discovery. Results demonstrate that price changes are determined by interactions between demand growth, mining productivity, and resource quality. In the worst cases with high demand and low productivity, development of material substitutes and large recycling rates help reduce the prevalence of price risk from over 90% to under 10%. Investing in these strategies yields significant benefits for manufacturers and governments concerned about costs of materials critical to decarbonization and other advanced technologies.  相似文献   

9.
In this paper, we first define sustainable supply chain, and its value, as a paradigm which pursues the maximization of supply chain profitability while taking its environmental and societal responsibilities. Secondly, we compare the supply chain surplus between the conventional and sustainable supply chains by means of adopting the basic economic analysis based on the concept of externality and social surplus in welfare economics. Through the proposed analysis, we show the possibility of sustainable supply chains which can provide more supply chain surplus to the companies. Finally, some limitations of this paper and future research directions are also presented.  相似文献   

10.
This paper studies the use of performance indicators in routing problems to estimate how transportation cost is affected by the quality of service offered. The quality of service is assumed to be directly dependent on the size of the time windows. Smaller time windows mean better service. Three performance indicators are introduced. These indicators are calculated directly from the data without the need of a solution method. The introduced indicators are based mainly on a “request compatibility”, which describes whether two visits can be scheduled consecutively in a route. Other two indicators are introduced, which get their values from a greedy constructive heuristic. After introducing the indicators, the correlation between indicators and transportation cost is examined. It is concluded that the indicators give a good first estimation on the transportation cost incurred when providing a certain quality of service. These indicators can be calculated easily in one of the first planning steps without the need of a sophisticated solution tool. The contribution of the paper is the introduction of a simple set of performance indicators that can be used to estimate the transportation cost of a routing problem with time windows.  相似文献   

11.

Background  

The production of fuel-grade ethanol from lignocellulosic biomass resources has the potential to increase biofuel production capacity whilst minimising the negative environmental impacts. These benefits will only be realised if lignocellulosic ethanol production can compete on price with conventional fossil fuels and if it can be produced commercially at scale. This paper focuses on lignocellulosic ethanol production in Europe. The hypothesis is that the eventual cost of production will be determined not only by the performance of the conversion process but by the performance of the entire supply-chain from feedstock production to consumption. To test this, a model for supply-chain cost comparison is developed, the components of representative ethanol supply-chains are described, the factors that are most important in determining the cost and profitability of ethanol production are identified, and a detailed sensitivity analysis is conducted.  相似文献   

12.
Although fields such as industrial ecology have advanced our understanding of how cleaner technologies, recycling, and lifestyle changes can reduce the impacts of production and consumption on people and planet, environmental deterioration and social injustices stubbornly persist. New strategies are needed to achieve change in an era of increasing urgency. This paper proposes that academics study the supply chains of individual corporations and link them to environmental and social impacts in geographically specific areas. Nongovernmental organizations (NGOs) have used this approach successfully, issuing reports about corporate activity related to deforestation, sweatshops, and other issues of social concern. But academics, by and large, have studied generic products, industries, and sectors. To verify this, after reviewing approximately 11,000 studies on supply chains, we identified just 27 academic papers that focused on individual corporations. These were primarily by NGOs and social scientists, with no studies by industrial ecologists meeting our review criteria. To uncover corporate supply chains, researchers used two distinct methodological approaches: in situ (interviews, surveys, and surveillance) and ex situ (trade data, document analysis, and maps). In this paper, we explain why and how academics should study the supply chains of individual corporations. This is done by combining approaches from industrial ecology, with those from geography, sociology, and other social sciences to develop a political‐industrial ecology of supply chains. This both physically links actual product flows with their environmental impacts, and explores how they affect justice, equity, and welfare. The work we propose offers clear collaborative linkages with NGOs, industry, and the media.  相似文献   

13.
Import and export of primates is controlled by the Endangered Species Act and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Permits are required for all international transactions, and certain primates may not be traded at all for commercial permits.  相似文献   

14.
Miscanthus has been identified as one of the most promising perennial grasses for renewable energy generation in Europe and the United States [Mitigation and Adaptation Strategies for Global Change 9 (2004) 433]. However, the decision to use Miscanthus depends to a considerable degree on its economic and environmental performance [Soil Use and Management 24 (2008) 235; Renewable and Sustainable Energy Reviews 13 (2009) 1230]. This article assessed the spatial distribution of the economic and greenhouse gas (GHG) costs of producing and supplying Miscanthus in the UK. The average farm‐gate production cost of Miscanthus in the UK is estimated to be 40 £ per oven‐dried tonne (£ odt?1), and the average GHG emissions from the production of Miscanthus are 1.72 kg carbon equivalent per oven‐dried tonnes per year (kg CE odt?1 yr?1). The production cost of Miscanthus varies from 35 to 55 £ odt?1 with the lowest production costs in England, Wales and Northern Ireland, and the highest costs in Scotland. Sensitivity analysis shows that yield of Miscanthus is the most influential factor in its production cost, with precipitation the most crucial input in determining yield. GHG emissions from the production of Miscanthus range from 1.24 to 2.11 kg CE odt?1 yr?1. To maximize the GHG benefit, Miscanthus should be established preferentially on croplands, though other considerations obviously arise concerning suitability and value of the land for food production.  相似文献   

15.
Flexible Services and Manufacturing Journal - In the past decade, subsidy policies aimed at demand-side of photovoltaic (PV) supply chains have created a dilemma. While they foster the growth of...  相似文献   

16.
Designing Green Supply Chains (GSCs) requires complex decision-support models that can deal with multiple dimensions of sustainability while taking into account specific characteristics of products and their supply chain. Multi-Criteria Decision Making (MCDM) approaches can be used to quantify trade-offs between economic, social, and environmental criteria i.e. to identify green production options. The aim of this paper is to review the use of MCDM approaches for designing efficient and effective GSCs. We develop a conceptual framework to find relevant publications and to categorise papers with respect to decision problems, indicators, and MCDM approaches. The analysis shows that (1) the use of MCDM approaches for designing GSCs is a rather new but emerging research field, (2) most of the publications focus on production and distribution problems, and there are only a few inventory models with environmental considerations, (3) the majority of papers assume all data to be deterministic, (4) little attention has been given to minimisation of waste, (5) numerous indicators are used to account for eco-efficiency, indicating the lack of standards. This study, therefore, identifies the need for more multi-criteria models for real-life GSCs, especially with inclusion of uncertainty in parameters that are associated with GSCs.  相似文献   

17.
This study is motivated by a real problem encountered in the manufacturing and distribution process at a local electronic manufacturer of security devices. We investigate the impact of operations redesign (i.e., operations merging) on the cost of safety stock in a supply chain. A simple safety stock method is used to derive a model for estimating safety stock levels. Our result shows that operations redesign can have a significant impact on safety stock investment. We extend and complement the existing literature in the following aspects: (i) we address the issue of safety stock deployment, i.e., we not only investigate the problem of how many operations should be delayed, but also determine which operations need to be delayed, (ii) we provide an efficient heuristic algorithm to determine which operations need to be merged, and (iii) we find the optimal operations redesign strategies under some special cases. Our analysis also reveals some important conditions and insights for better operations redesign, which enable us not only to decide when an operations redesign is appropriate, but also to suggest the scale and the format of the operations redesign.  相似文献   

18.

Purpose

This paper explores the issue of fairness in global supply chains. Taking the Western European clothing supply chain as a case study, we demonstrate how applying a normative indicator in Social Life Cycle Assessment (SLCA) can contribute academic and practical insights into debates on fairness. To do so, we develop a new indicator that addresses some of the limitations of the living wage for SLCA.

Methods

We extend the standard form of living wage available for developing countries to include income tax and social security contributions. We call this extension ‘living labour compensation’. Using publically available data, we estimate net living wages, gross living wages, and living labour compensation rates for Brazil, Russia, India, and China (BRIC) in 2005. We then integrate living labour compensation rates into an input-output framework, which we use to compare living labour compensation and actual labour compensation in the BRIC countries in the Western European clothing supply chain in 2005.

Results and discussion

We find that in 2005, actual labour compensation in the Western European clothing supply chain was around half of the living labour compensation level, with the greatest difference being in the Agricultural sector. Therefore, we argue that BRIC pay in the Western European clothing supply chain was unfair. Furthermore, our living labour compensation estimates for BRIC in 2005 are ~ 35% higher than standard living wage estimates. Indeed, adding income taxes and employee social security contributions alone increases the living wage by ~ 10%. Consequently, we argue there is a risk that investigations based on living wages are not using a representative measure of fairness from the employee’s perspective and are substantially underestimating the cost of living wages from an employer’s perspective. Finally, we discuss implications for retailers and living wage advocacy groups.

Conclusions

Living labour compensation extends the living wage, maintaining its strengths and addressing key weaknesses. It can be estimated for multiple countries from publically available data and can be applied in an input-output framework. Therefore, it is able to provide a normative assessment of fairness in complex global supply chains. Applying it to the Western European clothing supply chain, we were able to show that pay for workers in Brazil, Russia, India, and China is unfair, and draw substantive conclusions for practice.
  相似文献   

19.
This article presents a methodology for conceiving and planning the development of an optimized supply chain of a biodiesel plant sourced from family farms and taking into consideration agricultural, logistic, industrial, and social aspects. This model was successfully applied to the production chain of biodiesel fuel from castor oil in the semi-arid region of Brazil. Results suggest important insights related to the optimal configuration of the crushing units, regarding its location, technology, and when it should be available, as well as the configuration of the production zones along the planning horizon considered. Moreover, a sensitivity analysis is performed in order to measure how possible variations in the considered conjecture can affect the robustness of the solutions.  相似文献   

20.
Human hepatocytes are the model of choice for pharmacotoxicological studies, but their acquisition is often problematic due to ethical and logistical difficulties. The UK Human Tissue Bank is a not-for-profit organisation that acquires and processes human tissue, with a specialist interest in the isolation of human hepatocytes. A recent in-house survey of the processing of liver tissue over 1 year revealed that freshly isolated hepatocytes were underutilised due to mismatched consumer demand, despite the published need for them. We present the results of a telephone survey to investigate the reasons behind this paradox. This survey highlighted some problem areas, including "out of hours" availability of cells and personnel difficulties, but overall, demonstrated the value of such a service, with numerous researchers taking advantage of available good quality human hepatocytes. Although further work is required in optimising long-term storage protocols through cryopreservation, we have demonstrated that tissue handling of this type can be successful and beneficial to the pharmaceutical and biotechnology industries.  相似文献   

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