The impact of environmental regulations on forest product trade in China

Forest product trade plays an important role in the development of the Chinese forest industry. The trading value of forest product has shown a yearly growth rate of 12% during the last five recent years. Stringent environmental regulations in China have a profound impact on raw material supplies and industrial production in the forest sector; however, their impact on the forest product trade is still unclear. This study applies fixed and random effects models as well as a seemingly unrelated regression model to investigate the impact of environmental regulations on the trade of forest product from 2002 to 2015. The results indicate that the stringent environmental regulations promoted the import but restricted the export of forest product in general. Specifically, the stringent environmental regulations stimulated the import but had an ambiguous impact on the export of the paper product. The stringent environmental regulations had also stimulated the import of wood product but inhibited the export. In contrast, wooden furniture had been affected minimally; only export got slightly negatively affected by environmental regulations. Recommendations for resource managers:

• Trade‐offs between economic growth and environmental regulations are needed to smoothly promote the forest product trade in China.
• Paper and wooden furniture product sectors are less likely to be affected by stringent environmental regulations, because high value‐added products could compensate for environmental costs.
• The wood product sector is more likely to be negatively affected by stringent environmental regulations because environmental costs could severely impact the competitiveness of low value‐added products.

     

Quality Assurance of a Maker-Packer Model

We study a maker-packer production system in cigarette manufacturing where two different types of detectors are installed on the making and packing machines to maintain the product quality. The making machine detector has a continuously adjustable setting which determines the proportion of defective cigarettes removed. The packing machine detector has only discrete settings. We develop an economic model to derive the optimal settings for these detectors to achieve a specified average outgoing quality. The proposed maker-packer model is useful in other industries.     

Simulation of the shift from marine netcages to inland recirculating aquaculture systems

The recirculating aquaculture system (RAS) is an intensive production line that uses recycled water, and that should operate continuously, year-round, at full capacity. The RAS depends on enhanced water quality and minimized fish stressors, and its profitability relies on maximizing economic productivity per unit volume of rearing space. However, RAS operation requires coordinated management of many unit processes and/or operations. The aim of this study was to optimize operating parameters, including the number of fingerlings in the system, their arrival frequency, and fish weight on entry into the system and into the various stages of sorting along the production line. It was also necessary to minimize the start-up period, i.e. the period between establishment and achievement of full design capacity. A simulation model was developed to further the operating company’s interests, combining discrete-event and continuous-time stochastic simulations, meta-model and optimal-resource configurations—all to maximize annual profits, subject to operational and environmental constraints. Simulation outputs were monthly sales, fish stocking density (kilograms of biomass per cubic meter) and utilization of each culture tank at any given time, and effects of standing stock biomass and feed load on the biofilters. The simulation results were validated and implemented in an aquaculture farm.     

Economic design of inspection procedures using guard band when measurement errors are present

One of the most important aspects in designing production systems is implementing an adequate inspection procedure to ensure the product quality. Our literature study indicates that two important questions still remain unanswered. First, most of the previous studies on inspection procedures are mainly concerned with how to evaluate and analyze the adequacy of inspection procedures during a production stage. Although the issue of the adequacy of inspection procedures at this point is clearly important, many production processes may better benefit from designing enhanced inspection procedures during an early design stage. Second, the majority of previous studies do not incorporate possible economic impacts of measurement errors when inspection procedures need to be designed. More extensive efforts in designing inspection procedures need to be investigated based on economic considerations. Two approaches, the use of guard band and the selection of inspection precision level, are simultaneously examined for designing economic inspection procedures. By incorporating these two approaches, this paper proposes an optimization scheme for economic design of inspection procedures. A numerical example along with sensitivity analysis demonstrates the applicability of the proposed model.     

差异化竞争下考虑再制造专利许可的闭环供应链生产决策

针对高端产品和低端产品的差异化竞争,构建高端制造商将再制造专利许可作为外部竞争要素情形的闭环供应链竞合决策模型,研究消费者异质需求下再制造专利许可对闭环供应链生产决策、利润和环境效益的影响。研究结果表明:再制造专利许可是高端制造商的有效产品差异化竞争策略,可提高高端制造商利润,降低低端制造商利润;再制造专利许可策略对环境并不总是有利的,但消费者对再制造品的支付意愿越强,其环境效益越高。     

An EOQ model with process reliability considerations

The classical economic order quantity (EOQ) model assumes that items produced are of perfect quality and that the unit cost of production is independent of demand. However, in realistic situations, product quality is never perfect, but is directly affected by the reliability of the production process. In this paper, we consider an EOQ model with imperfect production process and the unit production cost is directly related to process reliability and inversely related to the demand rate. In addition, a numerical example is given to illustrate the developed model. Sensitivity analysis is also performed and discussed.     

EPQ with Process Capability and Quality Assurance Considerations

The classical economic production quantity (EPQ) model assumes that items produced are of perfect quality and that the unit cost of production is fixed. However, in realistic situations, product quality is never perfect but is directly affected by the production processes and the quality assurance programme. In addition, the unit production cost is not fixed but increases with quality assurance expenses. We present an EPQ model with imperfect production processes and quality-dependent unit production cost. After discussion of the procedure for determining the optimal solution, a sensitivity analysis of the impacts of the cost parameters on the optimal solution is provided. Finally, the problems associated with cost estimation are addressed.     

基于粗糙集与未确知模型的京津冀工业绿色发展的差异性与协调性分析

京津冀协同发展,工业绿色发展是重要突破口。本文基于绿色发展的内涵,参考四部委发布的《绿色发展评价指标体系》构建了涵盖工业资源利用、工业环境质量、工业环境治理、工业经济增长共4个二级指标16个三级指标的区域工业绿色发展测度指标体系,综合运用粗糙集理论与未确知模型约简指标、计算权重、设置分级标准,对京津冀工业绿色发展水平进行多指标综合测度;在此基础上构建耦合协调度模型测度其协调性。结果发现:(1)京津冀间工业绿色发展存在较大差异,京、津波动频繁,河北省上升趋势明显,均已达到中等以上水平;(2)京、津、冀工业绿色发展分别受工业环境治理、工业资源利用、工业环境质量的影响最为显著;(3)京津冀工业资源利用、工业环境治理及工业经济增长均处在濒临失调区,工业环境质量处在勉强协调区,工业绿色发展已达到优质协调区。因此,一方面京、津、冀工业绿色发展应分别聚焦工业环境治理、工业资源利用、工业环境质量精准施策;另一方面必须重视京津冀工业绿色协同发展。     

Comparing frontier methods for economic–environmental trade-off analysis

This paper uses a mechanistic frontier approach as a reference to evaluate the ability of conventional parametric (SFA) and non-parametric (DEA) frontier approaches for analyzing economic–environmental trade-offs. Conventional frontier approaches are environmentally adjusted through incorporating the materials balance principle. The analysis is worked out for the Flemish pig finishing case, which is both representative and didactic. Results show that, on average, SFA and DEA yield adequate economic–environmental trade-offs. Both methods are good estimators for technical efficiency. Cost allocative and environmental allocative efficiency scores are less robust, due to the well-known methodological advantages and disadvantages of SFA and DEA. For particular firms, SFA, DEA and the mechanistic approach may yield different economic–environmental trade-offs. One has therefore to be careful when using conventional frontier approaches for firm-specific decision support. The mechanistic approach allows for optimizing performances per average present finisher, which is the production unit in pig finishing. Conventional frontier methods do not allow for this optimization since the number of average present finishers varies along the production functions. Since the mechanistic production function is based on underlying growth, feed uptake and mortality functions, additional firm-specific indicators can also be calculated at each point of the production function.     

Factors which influence decision making in new product evaluation

New product development is indeed very important for companies. However, developing new products is a risky and uncertain process. In order to reduce the risks and uncertainties, companies need to evaluate their new product initiatives carefully and make accurate decisions. Although the outcome of a new product evaluation decision can be influenced by the environmental uncertainties that are beyond a company’s control, companies can successfully improve the accuracy of their new product evaluation decisions. This article presents an integrated framework for understanding how various factors affect decision making in new product evaluation and provides guidelines for reducing their negative impacts on new product decisions. The results indicate that the quality of new product evaluation decisions is affected by four major sets of factors, namely the nature of the task, the type of individuals who are involved in the decisions, the way the individuals’ opinions are elicited and the way the opinions are aggregated.     

环保投资分析模型研究

本在分析环保投资对环境质量和环境经济效益影响特征的基础上,提出环保投资效益模型,并以福建省泉州市废气污染治理为实例,对模型进行了适用性及实证分析,在一定程度上为实现经济与环境的可持续发展提供了环保投资的决策依据。     

Integrated production and quality model under various preventive maintenance policies

In this paper, we investigate the effect of various preventive maintenance policies on the joint optimisation of the economic production quantity (EPQ) and the economic design of control chart. This has been done for a deteriorating process where the in-control period follows a general probability distribution with increasing hazard rate. In the proposed model, preventive maintenance (PM) activities reduce the shift rate of the system to the out-of-control state proportional to the PM level. For each policy, the model determines the EPQ, the optimal design of the control chart and the optimal preventive maintenance level. The effects of the three PM policies on EPQ and quality costs are illustrated using an example of a Weibull shock model with an increasing hazard rate.     

环境规制对出口产品质量的影响研究——基于行业面板数据的实证分析

本文以环境规制作为解释变量,基于2003~2010年中国19个行业出口产品质量和环境规制数据,采用固定效用模型实证检验了环境规制对出口产品质量的影响。研究结果表明,环境规制对出口产品质量的影响呈“U”型,即环境规制增强前期成本效应大于创新效应,经营成本提高导致产品质量下降;环境规制增强后期创新效应大于成本效应,研发创新促使产品质量提高。不同行业对环境规制的敏感度不一样,将样本数据中涉及的19个部门,分为重污染行业和轻污染行业进行分类回归,回归结果显示环境规制对轻度污染行业出口产品质量的影响呈倒“U”型,即具有先促进后抑制的作用;环境规制对重度污染行业出口产品质量的影响呈“U”型,即具有先抑制后促进的作用。据此,提出有效利用环境规制以提高出口产品质量和发展绿色贸易的政策启示。     

Joint determination of production quantity,inspection schedule,and quality control for an imperfect process with deteriorating products

In this paper, we study the simultaneous effects of both deteriorating product items and deteriorating production processes on economic production quantity, inspection schedules, and the economic design of control charts. Deterioration times for both product and process are assumed to follow arbitrary probability distributions. The product quality characteristic, however, is assumed to be normally distributed. Applications of the proposed model are demonstrated through illustrative examples.     

基于正交设计原理的新型干法水泥生产过程的优化

通过试验设计优化投料和改善工艺过程是生产管理中经常采用的做法,产生了巨大的社会经济效益。正交试验设计首先是产生数据的计划,然后用统计方法对这些数据进行分析,目的是要从数据的考察中发现人们感兴趣的因素对试验结果的影响程度,以便采取相应的行动方案。本文针对一个研究专案,讨论了正交试验因素及各个因素试验水平的确定过程,并依据实际数据对多个产品质量特性的影响因素进行了分析,在此基础上得出了加强产品质量影响因素控制的相关建议。     

辽宁省碳排放、能源消费与经济增长的实证研究

在环境库兹涅茨曲线的基础上,通过VAR分析方法,从实证的角度揭示了辽宁省1978-2009年碳排量、能源消耗同经济增长之间的动态关系,通过广义脉冲反应分析,得出不同于以往的"N"型EKC曲线.Granger因果检验表明,辽宁省持续提升的GDP不断刺激碳排放量和能源消耗量的增加,但环境变化却不是推动省内经济增长的重要变量.辽宁目前的环境质量正随着经济的增长而恶化,环境质量的提升问题亟待解决.     

A genetic algorithm approach for solving a closed loop supply chain model: A case of battery recycling

Due to the implementation of government legislation, social responsibility, environmental concern, economic benefits and customer awareness the industries are under a great pressure not only to provide environmentally friendly products but also to take back the product after its use. The issue in reverse logistics is to take back the used products, either under warranty or at the end of use or at the end of lease, so that the products or its parts are appropriately disposed, recycled, reused or remanufactured. In order to overcome this issue, it is necessary to setup a logistics network for arising goods flow from end users to manufacturers. In this study, the optimum usage of secondary lead recovered from the spent lead–acid batteries for producing new battery is presented. The disposal in surface or sewage water or land of liquid content of the lead–acid batteries is strictly restricted. Because of the need for environmental protection and the lack of considerable lead resources, the spent batteries treatment and lead recovery are becoming crucial now-a-days. The objective of this paper is to develop a multi echelon, multi period, multi product closed loop supply chain network model for product returns and the decisions are made regarding material procurement, production, distribution, recycling and disposal. The proposed heuristics based genetic algorithm (GA) is applied as a solution methodology to solve mixed integer linear programming model (MILP). Finally the computational results obtained through GA are compared with the solutions obtained by GAMS optimization software. The solution reveals that the proposed methodology performs very well in terms of both quality of solutions obtained and computational time.     

部分追加设计在生产中的应用

在工厂的实际生产中，设计合理的最佳工艺条件、配料方案等是提高产品产量和质量的关键问题之一，本文是根据水泥工厂的原料燃料来源，工艺条件，技术水平及产品的品种和标号要求，用部分追加法设计熟料石灰饱和比（ＫＨ），硅酸率（ｎ）和铝氧率（ｐ）的最佳配方用于控制生产，提高产品质量和经济效益。     

MODELING OF A LANDLORD—TENANT AGRICULTURAL SYSTEM IN THE ENVIRONMENTAL CONTEXT

A hierarchical economic–environmental model is formulated to analyze the sustainable management of farming production in a landlord–tenant system. The problem under study is interdisciplinary and combines various agricultural, economic, social, and environmental factors. To maximize profit, the landlord chooses a rental payment and the duration of a lease contract. Tenants invest into farmyard fertilizer in order to improve future crop growth and maximize their profit. It is shown that the qualitative behavior of optimal trajectories in the landlord–tenant problem is mostly affected by environmental conditions rather than by the end‐of‐horizon and delay effects. A range of model parameters is identified, where the optimal trajectory coincides with the first‐best environmentally and socially efficient solution.     

A new multi-criteria approach dealing with dependent and heterogeneous criteria for end-of-life product strategy

Strict regulations, technological growth and environmental impacts are influent factors in the choice of the best strategy for end-of-life (EOL) product. In fact, EOL is one stage of the life cycle having gained the attention of the market.This study proposes an integrated methodology that relies on multi-criteria analysis and takes into account both quantitative and qualitative criteria while respecting mutual interactions between them. This has been performed by introducing, on the one hand, the 2-tuple linguistic representation model dealing with non-homogeneous information data, and on the other hand, the Choquet integral interaction modeling between criteria into the PROMETHEE method. Although it has been developed for EOL selection problems, the proposed method fits to all kinds of decision-making problems with heterogeneous information. As this work demonstrates, this multi-criteria analysis approach can offer a technical-scientific decision making support tool in the EOL product sector. We also perform a sensitivity to reveal the effect of the subjective parameter variations on the originally resulted ranking.