The problem of having accidents when using consumer products is the scope of this study. During our analysis of many reported accidents, we have found cases that resulted not from hazards contained in the products, but from not following the appropriate usage of the product. We named hazards that lead to such accidents “hidden hazards,” and have developed a method to discover them: Analysis Method to Discover Hidden Hazards (AMDHH), which is based on looking for deviations from the appropriate usage of the targeted product. A case study has been conducted using participants with little experience in risk assessment to see whether or not they could discover hidden hazards with AMDHH. A company survey was also conducted to evaluate AMDHH by people in charge of product safety. Participants in the case study managed to discover a variety of hidden hazards. In the company survey, the majority of participants agreed on the concept of AMDHH. It was also suggested that AMDHH could be used as an educational tool for risk assessment, designing product manuals, and for other purposes.
In some product categories, such as personal computers and motorcycles, customers usually customize a base model using optional items. These items are a strategic tool for revenue generation. Moreover, customers tend to buy a product with attributes that exceed their real needs, and on using the product, they are likely to be dissatisfied by the unnecessary features that it possesses. This paper, as a study of sales management, considers how a firm can select the most appropriate sales strategy: selling only a base product, a base product with optional items that are purchased before using the product, or a base product with after-sales services that are purchased after using the product. We develop utility functions for the over-specification (over-spec) tendency, analyze customers' choice of either options, after-sales services or none, and suggest the most adequate sales strategy for a firm. We find that when the over-spec tendency is weak but the price of additional items/services is relatively high, the “base model” strategy might be the most appropriate. In addition, we conclude that the “after-sales” strategy is dominant over the “options” strategy as long as the payment for customization is equivalent between these strategies. In other words, a firm that adopts the “options” strategy should reduce the cost that a customer bears when purchasing these options. This finding implies a rationale behind the common observation that a firm that wants to sell optional products in addition to the main product often offers these products as a package.
Ergonomic risk assessment is required to prevent work-related musculoskeletal disorders. Some assessment techniques in a broad range of complexity have been suggested. A complex tool quantifies a detailed risk, but it is time-consuming. In this study, a simple risk assessment method is proposed to improve (Kaizen) production line work by lowering the physical load on the worker. This method is based on Rapid Entire Body Assessment (REBA), but it can be used not only for posture analysis, but also for consecutive repetition work in any production line. A station work unit is divided into work elements. Two posture scores per work element are estimated for the upperlimbs as well as for the head, trunk and legs, respectively. Physical workload on the work unit is obtained from the weighted average of workloads on consecutive work elements applying a tact time. The daily workload is also examined for the workload on work units and production planning. The validity of the proposed method is investigated by an assembly line of vending machines for case study.
Closed loop supply chains (CLSC) can be both a forward supply chains and also reverse supply chains. Recently CLSCs are gaining much attention because of the growing need for environmental conservation. A CLSC has a number of features that distinguish it from simply a forward supply chain. One of them is requiring a large fixed cost because of the many facilities required to collect and disassemble products at the end of their service life. Another is the additional costs required for expanding capacity to handle the increase in remanufactured products and parts. In this paper, the problems of redesigning an existing logistics network in the CLSC is addressed. Redesigning an existing logistics network considers both opening new facilities and closing existing facilities. To reduce the fixed cost of facilities, opening hybrid facilities and decisions regarding the volume of products at each facility are considered. For the forward supply chain, redesign problems have been well researched, but this study is the first effort to consider redesigning an existing logistics network while considering profit from the sale of land property as part of the actual data in a CLSC. A new mathematical programming model is proposed. To validate the network redesign model proposed, it is applied to a real industrial case. Through the case study, it was found that the model proposed addresses redesigning an existing CLSC logistics network corresponding to recycling and resource savings, and validates the extent of economic efficiency.