Designing reliability information flows

It is well-known [Reliab. Eng. Syst. Saf. 75 (2002) 295] that in modern development processes it is essential to have an information flow structure that facilitates fast feedback from product users (customers) to departments at the front end, in particular development and production. As information is only relevant if it is used when taking decisions, this paper presents a guideline for building field feedback information flows that facilitate the decision taking during the product creation and realisation process. The guideline takes into consideration that the type of decisions depends on the span-of-control, therefore following Parsons [Structure and Process in Modern Societies (1990)] the span-of-control is subdivided into the following three levels: strategic, tactic, and executive. The guideline is illustrated with a case in which it is used for analysing the quality of existing field feedback flows.     

Prebiotic potential of barley derived β-glucan at low intake levels: A randomised,double-blinded,placebo-controlled clinical study

This randomised, double-blinded, placebo-controlled clinical study aimed to evaluate the in vivo prebiotic potential of barley β-glucan. Fifty-two healthy volunteers aged 39–70 years were randomly assigned to consume daily a cake containing 0.75 g of barley β-glucan or a placebo for 30 d. Stool samples were collected before, during and 2 weeks after the intervention for bacterial enumeration. Gastrointestinal side effects were recorded during the treatment period. In older subjects (?50 years old), barley β-glucan induced a strong bifidogenic effect and an increase of bifidobacteria into traceable range in cases of no detectable baseline levels. A concurrent significant increase in bacteroides was also observed in this age group. Ingestion of the experimental food resulted in no undesirable gastrointestinal side effects in older subjects. We concluded that the daily intake of a cake containing barley β-glucan is well-tolerated and demonstrated significant bifidogenic properties in older healthy volunteers consuming their usual diets.     

Application of functionalized coir fibre as eco-friendly oil sorbent

Synthetic polymers are based on the use of crude oil as their raw material. Oil spillage takes place during production, storage, transportation and usage at the water bodies and land surfaces. This may be due to tanker disasters, wars, operation failures, equipment breaking down, accidents and natural disasters. The spilled oil into land, river or ocean imposes a major threat to the environment and endangers the aquatic life. To overcome this problem, oil sorbents are commonly used for cleaning the oil spills. In this paper, coir fibre which was obtained as a waste from coconut fruit was functionalized to increase its hydrophobicity and oil sorption capacity. The product so formed was characterized by FT-IR, TGA and SEM which confirmed grafting of butyl acrylate monomer onto the coir fibres. The effects of time, temperature and monomer concentration on the grafting of coir fibre and oil absorption capacity have also been investigated. Results demonstrated that the modified coir fibre absorbed fair amount of crude oil and studies also indicate that a simple squeezing was sufficient to remove most of the oil sorbed by the fibres so that the sorbents can be reused several times for oil spill clean-up.     

Development of a Dynamic Skin Permeation System for Long-Term Permeation Studies

A dynamic skin permeation system was developed aiming to eliminate the deficiencies observed in the apparatus currently available. It consists of two half-cells in mirror image, each contains a stirring platform to permit a starhead magnet to rotate at a synchronous speed. The solution chamber is equipped with a sampling port, which can be tightly closed with glass stopper. The design characteristics of this new system was calibrated, using the commercially available Franz diffusion cell as the reference. The results clearly suggested that this newly developed skin permeation system shows consistently superior than the Franz diffusion cell in terms of the control of skin surface temperature and the efficiency of solution mixing. To investigate the potential effect of environment, the temperature on the stratum corneum surface was varied, while the dermal solution was maintained at constant body temperature, and its effect on the kinetics of skin permeation was studied. The energy requirements for various steps of skin permeation were determined. The results suggested that the skin permeation system developed in this investigation can be useful for the mechanistic analysis of long-term skin permeation kinetics.     

Field Reliability Prediction in Consumer Electronics Using Warranty Data

In innovative fast product development processes, such as consumer electronics, it is necessary to check as quickly as possible, using field data, whether the product reliability is at the right level. In consumer electronics, some major companies use the Warranty Call Rate (WCR) for this purpose. This paper discusses extensively the theoretical and practical drawbacks of the WCR. Subsequently, it is demonstrated, using a Weibull failure distribution, that only a few months after product launch, say three months, the warranty data offer the opportunity to estimate the parameters of the failure distribution. Of course, this requires that the warranty data are available in the quality department. Unfortunately, for some companies the field feedback information process from the repair centres to the quality department causes a delay of several months. These companies have to speed up their field feedback information process before they can fully take advantage of the proposed estimation procedure. Copyright © 2006 John Wiley & Sons, Ltd.     

用低阶煤降低炼焦用煤的生产成本

目前,由于炼焦煤的供应紧张和价格上扬,使焦炭生产者正面临着危机。最近两年来,美国炼焦煤的价格翻了一番。在澳大利亚,2005年的煤价比2004年上涨了20%,这是一场直接影响世界各钢铁生产企业的全球性危机。澳大利亚曾为美国的炼焦厂供煤,美国煤也曾大量输入日本和印度。美国、澳     

Organic Molecular Probes in Heterogeneous Catalysis. Hydrogenation of Norbornadiene on Gold

A few important examples are described to show that well-chosen molecular probes in organic reactions on heterogeneous catalysts can reveal much about the nature of the active sites and reaction mechanisms. This approach using norbornadiene in hydrogenation casts much light on the reasons why highly dispersed gold is an active selective catalyst. In the new polar mechanism, H₂ undergoes heterolytic fission in the very act of addition to adsorbed alkene, in contrast to the conventional Horiuti-Polanyi mechanism based on prior homolytic dissociation of H₂ on the metal surface.     

Long-Tern Skin Permeation Kinetics of Estradiol: (II) Kinetics of Skin Uptake, Binding, and Metabolism

The in vitro skin permeation system developed in this laboratory was utilized to investigate the kinetics of uptake, binding, and metabolism of estradiol, the female hormone, by the hairless mouse skin. The kinetics of uptake of estradiol and its subsequent metabolism to estrone by the skin were examined by exposing one side of a freshly excised skin to an estradiol solution, while the other side of the skin was protected with an impermeable aluminum foil.

The results concluded that the stratum corneum plays a rate-limiting role in the uptake and binding of estradiol and its metabolism to estrone by the skin. The mechanisms of the uptake and binding of estradiol to whole skin tissue (with stratum corneum) showed a sex dependence, with the rate higher in the female than in the male mouse. On the other hand, no sex-dependent difference was observed in the mechanism and rate of metabolism to estrone.

After stripping off the rate-limiting stratum corneum, the mechanisms of the uptake, binding and metabolism of estradiol all became sex dependent with identical rates observed between male and female mice in the initial 14 hrs of the experiment; Between 14 to 21 hrs, the rates increased substantially with the female skin, but not with the male skin. The increase in the rate of uptake of estradiol by the female skin was related primarily to the increased rate of metabolism of estradiol to estrone.     

The Ferry Cover Problem

In this paper we define and study a family of optimization problems called Ferry problems, which may be viewed as generalizations of the classical wolf-goat-cabbage puzzle. We present the Ferry Cover problem (FC), where the objective is to determine the minimum required boat size to safely transport n items represented by a graph G and demonstrate a close connection with Vertex Cover which leads to hardness and approximation results. We also completely solve the problem on trees. Then we focus on a variation of the same problem with the added constraint that only 1 round-trip is allowed (FC₁). We present a reduction from MAX-NAE-{3}-SAT which shows that this problem is NP-hard and APX-hard. We also provide an approximation algorithm for bipartite graphs with a factor asymptotically equal to  and a 1.56-approximation algorithm for planar graphs. Finally, we generalize the above problem to define FC _m , where at most m round-trips are allowed, and MFT _k , which is the problem of minimizing the number of round-trips when the boat capacity is k. We present some preliminary lemmata for both, which provide bounds on the value of the optimal solution, and relate them to FC.     

Improving the Quality of Information Flows in the Backend of a Product Development Process: a Case Study

Considerable research has gone into designing effective product development processes. This, coupled with the increasing need for products that are able to deliver reliable, complex functionality with a high degree of innovation, presents a major challenge to modern day industries in the business of developing products. In order to incorporate relevant field experience in the design and manufacturing of new products, increasingly detailed information needs to be retrieved from the market in a very short amount of time. In one particular consumer electronics industry, business process models describing the information flow in the backend of the product development process indicated massive data loss and also serious data quality degradation. This paper attempts to show how such losses can be mitigated and also proposes a business model that can adequately capture information of a higher quality and in a more structured manner. The end result will be a product development process that provides better feedback on current product performance and is more responsive to future market needs. Copyright © 2005 John Wiley & Sons, Ltd.