• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.4
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• pp.139-147
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• 2003

The most tunnel damage such as cracks or leakage which exist in tunnel lining commonly, is caused by the voids where exist behind the tunnel lining, through the tunnel safety inspections. These voids were analysed to affect to a stability of a running-tunnel seriously. The aim of this paper is to develope the lightweight foam concrete for tunnel backfilling material using stone-dust of cake state and to apply the lightweight foam concrete developed to the old tunnel. This paper shows the basic properties of lightweight foam concrete mixed with stone-dust including flow rate, unit volume weight, absorption rate and compressive strength. In addition, according to the designed compound ratio, the lightweight foam concrete was applied to the ASSM tunnel for an application assessment. The engineering application of the lightweight foam concrete as the old tunnel's backfilling material was confirmed in this assessment.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1999-2004
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• 2008

This study is about to constructing BOM for managing and integrating information, which is drawing, technical data, attribution, design, ordering, cost, weight, process, service, etc. based on train's system, elements, substructure, assembly, components, parts during whole train's lifetime of the next generation. The BOM is the mostly basic structure information as hierarchical data what are parts consisted specific products. The BOM was utilized as essential elements for collectively managing through informing all of the business activity from ordering to supplying. The BOM in railroad is consist of two parts. One is Engineering BOM for design, the other is Production BOM for production, which are utilized in development calculating the quantity of materials. Also the Maintenance BOM is applied to suppling parts and managing malfunction in railroad corporation like the Seoul Metro. There are many kind of BOMs, because of the special character for each step. Therefore We have need to develop BOM which is able to integrate drawing, technical data for helping good circulation between RAMS applied maintenance using database and helpful know-how for development and production. Also the BOM of the next generation must be consisted regard to whole life-cycle.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.5
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• pp.203-211
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• 2006

In this paper, the optimization of direct design system of steel frames by genetic algorithm involving advanced analysis are performed. For the analysis of steel frames advanced analysis accounting for geometric nonlinearity and material nonlinearity are executed. The genetic algorithm was used as optimization technique. The weight of structures is treated as the objective function. The constraint functions are defined by load-carrying capacities, deflections, inter-story drifts, and ductility requirement. The effectiveness of the proposed method are verified by comparing the results of the proposed method with those of other method.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.1
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• pp.113-120
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• 2007

A new material was tested and its applicability was investigated so as to give the capability of self-diagnosis of fracture in composite mortar. In the research for giving self-diagnosis capability, conductive mortar intermixed with cokes and carbon fiber powder(milled carbon fiber) was developed and its using for self-diagnosis material was proposed. Then after examining change in the value of electric resistance and AE characteristics before and after the occurrence of cracks at each weight-stage, the relationships of each factors were analyzed. As the results, it can be recognized that a new composite material with cokes and carbon fiber powder(milled carbon fiber) can be applied for self-diagnosis of fracture in mortar specimen.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.6
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• pp.205-213
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• 2008

The structure of PSC box girder with FRP strut has a form of supporting the cantilever part in the widened upper slab by modifying the existing PSC box girder efficiently, and it is able to build an economical and aesthetically pleasing bridge as it reduces the size of the lower structure by reducing the self-weight of the upper structure. In this research, loading test of PSC Box Girder using full-scale mock-up was conducted and FEM analysis was performed. By comparing results, structural safety of the FRP strut and the upper slab following application of the strut in the PSC Box Girder Bridge were evaluated.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.5
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• pp.143-151
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• 2008

In this paper, the optimum design of plane steel frames using second-order inelastic analysis and section increment method is presented. Since the second-order inelastic analysis accounts for geometric and material nonlinearities of the whole system as well as its component members, the design method based on second-order inelastic analysis does not require separate member capacity checks after analysis. A section increment method proposed by this paper is used as optimization technique. The weight of structures is treated as the objective function. The constraint functions are defined by load-carrying capacities, deflections, inter-story drifts, and ductility requirement. The effectiveness of the proposed method are verified by comparing the results of the proposed method with those of other method.

• Journal of the Korean Society of Clothing and Textiles
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• v.38 no.6
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• pp.845-856
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• 2014

This study focused on the production and usability evaluation of smart outdoor jackets that are designed to provide convenience to middle-aged people by embedding devices for lighting and location tracing. The results were as follows. 1. Jacket power supplier was a assembled system composed of battery, charger, controller and switch. A solar cell was attached on the upper arm, and a wire type EL on the center line of a raglan sleeve along with a GPS on the left sleeve with a transparent vinyl pocket. The total weight of the jacket embedded with devices was 385-520g. 2. Operation of function, activity, acceptability, safety, convenience for device use, appearance, practical maintenance were selected based on an analysis of evaluation criteria of previous smart wear research. Criteria were narrowed to three major categories of satisfaction, appearance and maintenance. 3. Use satisfaction criterion consisted of wearable device functionality and physical, psychological use convenience. The evaluation indicated actual functionality. EL functions were especially effective and necessary. Convenience of use showed that a smart jacket was thought to be safe and the size was moderate regardless of age and gender. Outer appearance was satisfactory and respondents praised the color. The practical maintenance evaluation indicated that there was no challenge in doing the laundry since the solar battery and GPS were detachable. The practical use of smart outdoor jackets confirmed by fabric that was washable and dried quickly.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.3
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• pp.45-51
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• 2013

We developed a new antibacterial material, a non-woven fabric, a sulfur solution, and a new adhesive system to manufacture a new type of functional hybrid corrugated board in previous studies. Based on experimental data, the prototypes of functional hybrid corrugated boards were manufactured and their physical properties and functionalities, including antibacterial property and the freshness maintenance of sweet persimmon, were measured in this study. The functional hybrid corrugated board could be manufactured in the actual process with linerboards, non-woven fabrics, and other materials without any troubles, and was strong enough to be used as a packaging box for agricultural products. The antibacterial property of the hybrid corrugated board showed a value high enough to eliminate bacteria, which could deteriorate the sweet persimmons. Based on appearance observations, weight loss and firmness measurements, the freshness of sweet persimmons in the functional hybrid corrugated board was maintained better than it was in the conventional corrugated board.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.491-494
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• 2009

This paper introduces the design concepts and characteristics of WinDS3000$^{TM}$ which is a trade mark of Doosan's 3MW offshore/onshore wind turbine. WinDS3000$^{TM}$ has been designed in consideration of high RAMS (Reliability, Availability, Maintainability and Serviceability) and cost effectiveness for the TC Ia condition in GL guideline. An integrated drive train design with an innovative three-stage gearbox has been introduced to minimize nacelle weight of the wind turbine and to enhance a high reliability for transmission. A permanent magnet generator with full converter system has been introduced to get higher efficiency in part load operation, and grid friendliness use of 50 Hz and 60 Hz grid. A pitch regulated variable speed power control with individual pitch system has been introduced to regulate rotor torque while generator reaction torque can be adjusted almost instantaneously by the associated power electronics. An individual pitch control system has been introduced to reduce fatigue loads of blade and system. The wind turbine has been also equipped with condition monitoring and diagnostic systems in order to meet maintainability requirements. And internal maintenance crane in nacelle has been developed. As a result, the maintenance cost was dramatically reduced and maintenance convenience also enhanced in offshore condition.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.11
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• pp.1586-1590
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• 2004

An experiment was carried out with day-old "Sonali" (♂RIR$\times$♀Fayoumi) chicks to investigate the efficacy of locally made low cost brooders for brooding chicks in rural areas. Three types of indigenous brooders viz. charcoal, haricane and sawdust brooders were used for brooding chicks throughout the experimental period of 28 days. The efficiency of the brooders was observed in respect of their ability to maintain temperature, fluctuation in temperature during operation and cost effectiveness. Following initial trial of temperature maintenance for 48 h, the chicks were put under the brooder stoves and brooded up to 28 days. The experimental birds were fed on chick starter diet. Maintenance of temperature with sawdust brooders was found satisfactory and optimum for brooding the chicks at different stages of brooding and at the same time involved least cost for brooding in comparison with charcoal and haricane brooders which did not perform well in generating heat necessary for brooding and were not economically feasible for poor farmers. On the other hand, performance of charcoal brooders was better in respect of temperature maintenance during initial stage (when the brooder was started) but the temperature fluctuated rapidly, whereas fluctuation of temperature was gradual in sawdust brooders. Body weight gain and feed conversion were best in sawdust brooders. Survivability was highest in sawdust brooders and lowest in haricane brooders. Sawdust brooders may be appropriate for brooding chicks in rural areas, where electricity is not available.