Reverse production system infrastructure design for electronic products in the state of Texas

Rapid technology advances have shortened the lifecycle of electronic products, resulting in the increasing number of discarded products in recent years. Due to the growing environmental concerns, several state governments have passed new regulations in order to reduce the amount of waste stream, to divert the discarded products from landfills, and to dispose the retired electronic products properly. As a result, an effective reverse logistics infrastructure is required to support the product recovery activities. In this paper, we propose a solution methodology for designing the infrastructure of the reverse production system by utilizing the mixed integer linear programming (MILP) model. A case study for designing the reverse production system in the state of Texas is also presented. Statistical analyses are carefully utilized to estimate design parameters in the case study from the available historical information from previous studies. Finally, discussions, recommendations, and insight information in designing and operating the reverse production system are presented.     

The support of meat value chains by genetic technologies

Ongoing meat and food industry consolidation has resulted in the creation of larger and more complex, vertically integrated and/or coordinated food production systems. These systems have also been focused on development of differentiated ‘Value Chains’ as a departure from the traditional commodity oriented ‘Supply Chains’. The main goal of value chains is to achieve sustainable competitiveness through focusing resources on efficiently producing goods that offer superior consumer-recognized value. A closely-aligned value chain often contains vertically and horizontally linked players such as genetics and genetic improvement program(s), farmer(s), processor(s), distributor(s), and retailer(s). In this paper we postulate that the underlying foundation of the success of meat value chain accomplishments has been through substantial development of animal genetic technologies enabling sustainable production of animal protein-based consumer products of desirable quantity and quality. It is plausible to assume that further advancement in genomic selection and eventually proteomics will enable implementation of more complex genetic improvement programs leading to further development of differentiated meat value chains focused on ever changing consumer needs.     

Surface Molecular Mobility for Copolymers Having Both Hydrophobic and Hydrophilic Side Chains Via Dynamic Contact Angle Measurement

The reorganization of a surface structure in response to a change in environmental media was investigated for copolymers having both hydrophobic polydimethylsiloxane (PDMS) and hydrophilic methoxypoly-ethyleneglycol (MPEG) side chains via dynamic contact angle (DCA). These copolymers showed a large contact angle hysteresis and a dependency of the advancing and receding contact angle on dipping velocity (DV). Composition dependency of DCA for these copolymers is also discussed. In addition to this, adhesion tension relaxation, F(t), for MMA/MPEGMA/PDMSMA was determined. F(t) in the advancing process increased with elapsed time and decreased in the receding process. These phenomena were explained by the adsorption and reorientation of hydrophilic segments to the water/copolymer interface in water. In XPS analysis, more oxygen atoms were detected on the surfaces of MMA/MPEGMA after immersion in water than before. For MMA/MPEGMA/PDMSMA, the atomic ratio of Si to C increased with an increase in PDMSMA content.     

Toxicity in sequential dose-response experiments

Often, in dose-response studies, it is desirable to arrange treatments in a region defined by the unknown surface. We accomplish such arrangements using sequential designs that are functions of previous outcomes. Here, for a class of randomized up-and-down designs for dichotomous responses (e.g., toxicity/no toxicity) and predetermined sample size, distributional results for the total number of toxic responses are derived. These results are useful in selecting sequential design parameters and have obvious ethical implications.     

Environmentalism and the multinational corporation: a viewpoint — part I

In this essay, we attempt to apply lateral pressure theory to conceptual thinking on MNC. “Power as capability” is implicit in the rationales firms engage in international production, viz., ownership advantage, location advantage, and internalization advantage. It is argued that issues of control (an internalization advantage) are crucial for the MNC, and the development of a complex mechanism for integrating information flow represents one important aspect of its capability. Part Two of this essay will explore in detail “power as influence” perspective of MNC bargaining power, relocation of production, and the impact of environmentalism in its value chains.     

Representing lattices using many-valued relations

This paper provides a representation theorem of lattices using many-valued relations. We show that any many-valued relation can be associated to a unique lattice which is a meet-sublattice of a product of chains. Conversely, to any lattice we can associate a many-valued relation such that its associated lattice is isomorphic to the initial one. Thereby, we obtain a representation theorem of lattices using many-valued relations. Moreover, since several many-valued relations might have the same associated lattice, we give a characterization of the minimal many-valued relation that can be associated to a lattice. We then sketch a polynomial time algorithm which computes such a minimal relation from either a lattice or an arbitrary relation. This representation presents several advantages: it is smaller than the usual binary representation; all known reconstruction algorithms working on binary relation can be used without loss of efficiency; it can be used by existing data mining processes.     

Evolutionary algorithms approach for integrated bioenergy supply chains optimization

In this paper, we propose an optimization model and solution approach for designing and evaluating integrated system of bioenergy production supply chains, SC, at the local level. Designing SC that simultaneously utilize a set of bio-resources together is a complicated task, considered here. The complication arises from the different nature and sources of bio-resources used in bioenergy production i.e., wet, dry or agriculture, industrial etc. Moreover, the different concerns that decision makers should take into account, to overcome the tradeoff anxieties of the socialists and investors, i.e., social, environmental and economical factors, was considered through the options of multi-criteria optimization. A first part of this research was introduced in earlier research work explaining the general Bioenergy Decision System gBEDS [Ayoub N, Martins R, Wang K, Seki H, Naka Y. Two levels decision system for efficient planning and implementation of bioenergy production. Energy Convers Manage 2007;48:709–23]. In this paper, brief introduction and emphasize on gBEDS are given; the optimization model is presented and followed by a case study on designing a supply chain of nine bio-resources at Iida city in the middle part of Japan.     

工艺尺寸链计算方法的研究

机械加工工艺制订过程中,工序尺寸的确定十分重要。当工序基准与设计基准重合时,可按工序余量和经济精度采用反推方法确定工序尺寸,当工序批准与设计不重合时,需用尺寸链原理计算工序尺寸。本文结合齿轮内孔的加工,详细介绍一种解算工艺尺寸链的新方法。     

加权阵列天线的设计方法马尔柯夫链法

加权阵列天线的设计目前主要采用统计法。本文通过总结统计法的优缺点,提出了一个新方法马尔柯夫链法。新方法采用将阵列分成若干个区的方式,反映了在阵列的不同部分,单元相关性不同这一特性,改变了以前设计加权天线对笼统地考虑整个阵列上的单元排列。应用随机过程的马尔柯夫链特性,得到了各个随机量处于不同状态的概率。由于马尔柯夫链法反映了实际低副瓣天线的口径分布,因而利用此种方法更容易得到低副瓣的加权阵列天线。     

Preparation of high-modulus nylon 6 fibers by vibrating hot drawing and zone annealing

To prepare high-modulus fibers, the vibrating hot-drawing and zone-annealing methods have been applied to nylon 6. The vibrating hot drawing was repeated two times, increasing the applied tension; further, the zone annealing was superposed on the vibrating hot-drawn fibers. The superstructure and mechanical properties of each step fiber were investigated. The vibration under a cooperation of heating and tension was very useful for increasing the draw ratio, birefringence, and orientation factor of the amorphous chains. Consequently, the obtained fiber indicated high moduli, namely, Young's modulus of 23 GPa and the dynamic storage modulus at room temperature of 25.3 GPa. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:1993–2000, 1998