As a method for attaching car windows, urethane application is often used. Recently, tests on new urethane applications have been carried out to improve quality and productivity of assembly lines, and to reduce costs through the entire process of attaching car windows. In the study of the new urethane applications,a parameter design method is used to evaluate the material selection and the conditions for attaching windows. As a result, we found the material that satisfies adhesive performance requirements and processing requirements. The results are reported here.

Crank shaft is a piece of intricate shaped component part. A stable bending strength and the strength against torsion fatigue is demanded for its rotating mechanism. But it is very difficult to improve the strength with a high stability for such a complex shape component in a short period of time. The authors conducted an experiment to successfully find the chemical compositions for a stable product using simple shaped test pieces using Taguchi methods. In the study, both non-dynamic and dynamic characteristics were used. From the results of the experiment, the optimum chemical composition for a high strength with a stabilized quality for crank shaft material was obtained.

The fundamentals in measurement technology include the calibration of measuring devices and evaluation of measurement error. In many cases, the magnitude of measurement error deeply relates to the ability of operators. The authors have been studying the relationship between ability and items such as the operator's character, constitution and behavioral habit. In the study, scales were measured by operators, and life-related questionnaires were collected in order to discover the items (characteristics) that contribute to measurement ability. Forecasting the ability of a person is to find out his or her aptitude. In the case of measurement, it is important to efficiently judge if the ability belongs to a good or a bad category. In this paper, the judging method was studied using the Schmidt orthogonal expansion considering the directional aspect of operators.

The authors studied a method for expressing both a body's surface roughness and its swell by using practical examples of product processing. As surface roughness and swell are two types of product size variations, they analyzed the surface roughness (as a true value) as one of the size variations and further examined the method of expression. As a result, they could express the information of the surface variation through the use of S/N ratio. In addition, they examined cases including level differences. The results are reported here. In the end, they obtained clear results, which in the case of using level difference information to make measurements, they could study the method for simultaneously analyzing the dimensions, the shape error and the roughness by applying the dimensions to a reference point.

In an electro-photographic system, miniaturization of a toner particle is an effective technology to get high quality print images. And one of many approaches is the polymerize technology that can make a super-fine polymer for toner particles easily. But it is not a simple matter to use a super-fine toner into practical applications. The greatest problem is in cleaning process for a photosensitive drum. It is difficult to remove super-fine toner particles remained on surface of a photosensitive drum. Therefore, the development of cleaning process is an important issue in order to utilize a super-fine toner, like a polymerized toner. Currently, the perfbrmance of cleaning process is tested with use of "cleanliness" that is one of typical quality characteristics. Thinking about that a super-fine toner will be demanded in several years, this traditional test will be of no use definitely. We need the evaluating technology for forecasting the performance of cleaning process before releasing products. This study deals with the evaluating technology with the use of rotative torque of a photosensitive drum, and no quality characteristic like "cleanliness" is measured. This study is proved that we can develop high performance cleaning process efficiently before a super-fine toner is available.

Optical disks such as MO (magneto-optical) and CD-R (Compact Disk Recordable) are widely used for digital data storage. In this study, the generic function of optical disks was defined that laser lighting time as the input is proportional to mark length as the output, The data marks on the optical disk are written by laser light intensity modulation (LIM), which is one of the thermal recording methods. The LIM recording causes nonlinearity on the mark length in the generic function due to thermal accumulation. In this optical disk recording process, it is necessary not only to reduce the variability of mark length bu七 to improve its nonlinearity.

The research paper describes the problems and the solutions in introducing and promoting Quality Engineering to corporate structures. We conducted the study based on our company's experience, in which Quality Engineering is applied to the research, technology development and new product development. In the 25 years from 1972 to 1997, we experienced some success and failure in promoting the use of Quality Engineering. From our experience, we formed a hypothesis regarding the Key Factor for Success (KFS) for promoting. Quality Engineering, and in the following 5 years, we verified the effectiveness of the hypothesis.