• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2007.05a
• /
• pp.594-597
• /
• 2007

The notebook system use the radial fan to cool the main chipsets which generate heat. It needs to improve cooling performance by increasing fan RPM or increasing fan volume. But the former accompanies acoustic noise problem and the latter has a limitation due to notebook height and cooling area. So this study shows fatal parameters in the fan performance view point, and optimization process with Design Of Experiment. With this result, the fan CFM increases with same size of fan and we can use it as a result of decreasing fan acoustic noise.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.21 no.3
• /
• pp.220-226
• /
• 2011

This paper presents the novel work for source localization of serial multiple impacts in a plate sructure. It is difficult to identify the source of serial multiple impacts with the current source localization techenology(SLT) because of the overlapping of dispersive wave induced by multiple impacts and the reflaction from the edge of the plate. In this paper, the new method is suggested for source localization. The method is developed based on the SLT with pre-signal processing such as some limitation for the selection of three sensors, the frequency range for TFA and impact time interval. Results from numerical simulation and experiment in isotropic plate structure are presented, which show the capability of the proposed method.

• Journal of Korean Society of Transportation
• /
• v.6 no.2
• /
• pp.49-56
• /
• 1988

Alternate use of lane at a signalized intersection is a quite different control of the operation of an intersection. This control introduces a new stop line and signal before the original stop line. All of the lanes between the two stop lines are used for left turn traffic or through traffic at a time. The purpose of the control is increasing the capacity of a n intersection without widening the approach width. this paper contains a study on the condition of a application, the proper distances between the two stop lines, the reasonable offsets(rear) to guarantee clearing the vehicles of previous phase, the comparison of approach capacity between the existing control and this control. The study results reveals that the offsets(rear) are rather stable showing the range(maximum value minus minimum value) of it's value does not exceed 3.6 seconds according to the field data. The approach capacity will be increased by 27%, 43%, 59%, 84% when the distances between the stop lines are 30.0m respectively. The control might have theoretical limitation to operate in practice. So an experimental application of the control at some suitable intersections prior to expanding it.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.32 no.2
• /
• pp.51-57
• /
• 2000

Cylinder machine usually gives more fiber orientation than fourdrinier and has limitation in machine speed because of fiber wash-off caused by centrifugal force when machine speed increases. This study aimed for the improvement of paper formation and productivity by setting an apron in vat inlet and by adjusting mould water head. Improvement of formation and increase of machine speed were achieved, which ultimately improve productivity. Installing an apron successfully decreased fiber wash-off. Fiber orientation and two-sideness of ash distribution became less severe. The proper adjustment of water head inside the cylinder mould proved to be an important factor not only in paper formation but also in decreasing paper two-sideness.

• Annals of Clinical Neurophysiology
• /
• v.10 no.1
• /
• pp.33-37
• /
• 2008

Diabetic polyneuropathy (DPN) is the most common form of diabetic neuropathy, and causes a significant morbidity with an impact on the quality of life in the patients with diabetes. Since DPN frequently induces foot deformity and ulceration, which finally leads to foot amputation, the early detection and treatment is very important for the prevention of a permanent structural change. In the early stage of DPN, the diagnostic methods which can evaluate the function or structure of small nerve fibers should be employed because small nerve fibers are first involved in the course of DPN. However, the nerve conduction study cannot reflect the function of the small nerve fibers, and thus, has a definite limitation in the early diagnosis of DPN. For the early detection of DPN, electrodiagnostic data should be interpreted on a clinical context, along with the careful evaluation of the small nerve fiber functions using the tests such as the analysis of intraepidermal nerve fiber density.

• Korean Management Science Review
• /
• v.23 no.2
• /
• pp.187-198
• /
• 2006

Efficient scheduling for software development is a major concern for software engineers. Industries simultaneously try to perform a variety of projects with the limited resources on schedule. A way to overcome the limitation of resources is sharing of the resources through the projects. This study discusses the matrix organization for software development. A scheduling for matrix organization is a special case of project management problem. The ultimate goal of scheduling problem in this study is to minimize the overall duration of the multiple projects. A genetic algorithm is presented to solve the scheduling problem of the matrix organization and is substantiated with numerical results.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2000.04a
• /
• pp.330-336
• /
• 2000

This paper discusses the potential of system dynamics modelling to support balanced scorecard. The balanced scorecard is a conceptual framework for translating an organisation's strategy into a set of performance indicators. These performance indicators are distributed across the 'classic'model's four perspective: Customers, Internal Business Processes, Financial, and Learning and Growth. This balanced scorecard, whilst having significant strength, suffers from the limitation of all performance indicator systems, namely that the interrelationships between indicators are overlooked and there is no way of taking into account the impact of delayed feedback which flows from introduction of new policy and legislative changes. System Dynamics is a methodology for understanding complex problems where there is dynamic behaviour and where feedback impacts significantly on system outcomes. System dynamics provides a rigorous basis for qualitative testing of the effects of performance indicators in complex environments such as health or social security. This can be supplemented with quantitative system dynamics simulation tools that further test the validity of indicators and the business rules implicit in them. System dynamics modelling has an important role to play in extending feedback cycle in performance measurements to a full systems approach.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2000.04a
• /
• pp.530-533
• /
• 2000

Recently, Manufacturers have recognized the importance of recycling because of the limitation of natural resources and new and proposed laws and legislations that assign responsibility to manufacturer for the ultimate disposal of their products and the environmental problems. In this paper, products assembled recyclable parts and non-recyclable parts are collected after consumer usage and go into a plant. And the collected recyclable parts are disassembled through the disassembly process and have three attributes - re-usable attribute, re-manufacturing attribute and dumping attribute. In this situation, we deal with a production planning for recycle-oriented manufacturing system. The proposed model maximizing the profit in a system is formulated as a mixed-integer linear programming. And then a numerical example is used to evaluate the effectiveness of the proposed model

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2000.04a
• /
• pp.634-636
• /
• 2000

The importance of EDI has been so emphasized that we need exchange/maintain electronic documents effectively, and convert then to other formats. The traditional EDI, however, is facing on the limitation of growth because of it's high expense, and the closenees of sharing information. The EDls of next generation, like open EDI, object-oriented EDI, and Internet EDI, have appeared to solve these problems. Finally, XML/EDl, which is very effective to solve these kinds of problems, is now replacing the traditional EDI and the HTML in Internet and is influencing on e-Business. So, we are going to suggest a solution which uses XML/EDl as a substitute for the traditional one. First, we analyzed the problems of the traditional EDI system and organized the structure of XML/EDl system. Next, we have developed the prototype of Internet bookstore to show the effectiveness and strength of XML/EDl over the traditional EDI.

• Microbiology and Biotechnology Letters
• /
• v.25 no.6
• /
• pp.598-605
• /
• 1997

The characteristics of cell growth and cellulose production by Acetobcter xylinum BRC5 were studied in shaking flasks and jar fermentors. Of the substrates tested, the highest cellulose yield was obtained from the fructose medium. Some inductive cultivation was observed and then cellulose was produced with cell growth. When glucose alone or mixture of glucose and fructose was used as the carbon source, cellulose could be biosynthesized under the glucose limitation. Corn steep liquor (CSL), as a low-cost nitrogen source, was a good substitute for yeast extract. In a jar fermentor experiment, 4.14 g/l of disintegrated cellulose was obtained from 8% CSL- medium containing 0.5% glucose and 1.5% fructose.