• Journal of Power Electronics
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• v.9 no.2
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• pp.180-187
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• 2009

When converters operate in megahertz range, the passive components and magnetic devices generate high losses. However, the eddy current issues and choices of magnetic cores significantly affect on the design stage. Apart from that, the components' reduction, miniaturization technique and frequency scaling are required as well as improvement in thermal capability, integration technique, circuit topologies and PCB layout optimization. In transformer design, the winding and core losses give great attention to the design stage. From simulation work, it is found that E-25066 material manufactured by AVX could be the most suitable core for high frequency transformer design. By employing planar geometry topology, the material can generate significant power loss savings of more than 67% compared to other materials studied in this work. Furthermore, young researchers can use this information to develop new approaches based on concepts, issues and methodology in the design of magnetic components for high frequency applications.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1995.10a
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• pp.17-24
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• 1995

This work proposes an optimality criteria applicable to the optimum design of plane frames. Stress constraints as well as displacement constraints are treated as behavioural constraints and thus the first order approximation of stress constraints is adopted. The design space of practical reinforced concrete frames with discrete design variables has been found to have many local minima, and thus it is desirable to find in advance the mathematical minimum, hopefully global, prior to starting to search a practical optimum design. By using the mathematical minimum as a trial design of any search algorithm, we may not full into a local minimum but apparently costly design. Therefore this work aims at establishing a mathematically rigorous method ⑴ by adopting first-order approximation of constraints, ⑵ by reducing the design space whenever minimum size restrictions become "active" and ⑶ by the of Newton-Raphson Method.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.4B no.3
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• pp.114-121
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• 2004

Switched reluctance motors have received much attention as a driving means for various industrial applications because they have simple construction, low cost and high efficiency. Nevertheless, the requirements of drive converters make it difficult to lower the overall system cost as compared with the DC motor application. Single phase switched reluctance motors (SPSRMs) provide a solution to the high cost problem since the number of switching power devices can be reduced and consequently the trials for application are increased. However, research involving SPSRMs, especially in the area of design work, is insufficient. This paper introduces a novel design methodology of single phase SRM. The design work for SPSRM comprises the determination of many variables such as stator and rotor pole arc as well as on, off and so on. Managing all variable combinations leads to lengthy computation time and a fault in the design process. For that reason, a reliable technique and brief procedure term are required in SPSRM design.

• Proceedings of the Korea Society of Design Studies Conference
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• 1999.05a
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• pp.60-61
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• 1999

Design appreciation is a once a week 16 week course Primarily it is a series of presentation and discussion about product design, aiming at increasing the awareness of design among students, and stimulating their own work.(omitted)

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.7-11
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• 2008

In order to investigate the application of bamboo in various ways in floral designs, we analyzed 108 bamboo items from the monthly magazine 'Fleur' and from the International Flower Contest held from 2001 to 2006. We analyzed the frequency of usage of bamboos by the used parts, kind of design, type of design, and arrangement method in the design work. In terms of the used parts of the bamboo, stems took 90% of the whole work. Among the 77 designs that used stems, excluding the 20 work items presented in the International Flower Contest which has been held in April, number of the bamboo work items peaked at the beginning of the year in January and February, and during summer (July and August). Upon analyzing the type of stems that were used in the 97 works, 63% of the works used bamboo in natural state, but not processed. 48% of the works used the vertical-parallel method among the arrangement methods. Other categorized works were rounded works that were not included in the vertical, horizontal or diagonal mathod. More than 50% of the works, including the table decoration, used space decoration. Among the types of work design that used bamboo as material, 64% were decorative type, 30% graphic type, and 4% formal-linear type.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.7 s.155
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• pp.1090-1102
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• 2006

The purpose of this study is to develop an improved work clothing which is much safe, comfortable, mobility and convenient than what workers currently wear at construction site. The investigation has been conducted to evaluate current work clothing to grasp any problems, discomforts and damages related to the work clothing. For the best and accurate data, hands-on investigation and a short-interview have been performed at the construction site as well as formulating a questionnaire. The questionnaires was answered by 425 workers and safety manager of 13 different construction site. The result of the questionnaire enables us to design a sample work clothing, many pa π s such as material, pattern and design have been improved. To improve the amenity of heat, the surface of a material was used by $Aerocool^{\circledR}$ fiber which contains inside dryness function. In order to absorb perspiration on the back the armpits, mesh martial that is mixture of $Coolever^{TM}$ fiber and $Mirawave^{TM}$ fiber was used to absorb perspiration in an effective manner. And a sleeve's bottom part and trousers' bottom part's cover method have been changed. Sample work clothing was shorten at the side of upper garment up to 2cm and lengthen the length of the back by 3cm. To reduce the tightness around armpit more room was given in that area. Darts were added to the elbow, the hip, and the knees that also followed an ergonomic pattern. A sample work clothing evaluated an objective assessment and subjective assessment to compare to a current work clothing. Assessment group consists of seven subject groups and nine expert groups to evaluate external appearance and adaptability to the movements. In all aspects of the test, the result of evaluation process of the sample work clothing received more positive assessment than the current work clothing.

• Journal of Information Technology Services
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• v.13 no.3
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• pp.93-110
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• 2014

With the explosive proliferation of smart devices that may be connected to the fast Internet, virtual desktop interfaces(VDI) are being implemented in enterprises allowing employees to work anywhere anytime in the same technological environment. As this kind of systems are intended to raise the work performance, a research model is constructed from the review of research literature on service quality and work design. The model consists of VDI system service quality (ubiquity, availability, compatibility, security and ease of use), system satisfaction, task performance and job satisfaction. As VDI is designed as a support system for cooperative work, the task interdependence adopted from the work design theory is postulated here as moderating the effect of user satisfaction on task performance and job satisfaction. 147 data points were collected by a survey of VDI users in a global firm and subjected to PLS analysis. Interestingly, ubiquity and compatibility seem to be not statistically significant for user satisfaction while availability, security and ease of use of VDI system are statistically significant. Task interdependence is found to be a relatively strong mediator between system user satisfaction and task performance, however, interestingly, the coefficient come out as negative. This may indicate that the influence of VDI user satisfaction on task performance would not be high in highly interdependent tasks. Considering that VDI is intended for supporting 'interdependence' in cooperative work, this finding is a bit surprising. In-depth discussions are made in the discussion followed by future research directions.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2001.01a
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• pp.211-218
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• 2001

This paper introduces a method of constructing expert systems in an integrated environment for automatic software design. This integrated environment may be applicable from top-level system architecture design, data flow diagram design down to flow chart and coding. The system is integrated with three CASE tools, FSD (Functional Structure Diagram), DFD (Data Flow Diagram) and structured chart PAD (Problem Analysis Diagram), and respective expert systems with automatic design capability by reusing past design. The construction way of these expert systems is based on systematic acquisition of design knowledge stemmed from a systematic design work process of well-matured developers. The design knowledge is automatically acquired from respective documents and stored in the respective knowledge bases. By reusing it, a similar software system may be designed automatically. In order to develop these expert systems in a short period, these design knowledge is expressed by the unified frame structure, functions of th expert system units are partitioned mono-functions and then standardized components. As a result, the design cost of an expert system can be reduced to standard work procedures. Another feature of this paper is to introduce the integrated environment for automatic software design. This system features an essentially zero start-up cost for automatic design resulting in substantial saving of design man-hours in the resulting in substantial saving of design man-hours in the design life cycle, and the expected increase in software productivity after enough design experiences are accumulated.

• Journal of the Society of Naval Architects of Korea
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• v.50 no.6
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• pp.458-465
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• 2013

Ship design engineering refers to the development and design of shipbuilding architectures in a drawing which reflects all relevant manufacturing processes. This paper provides analysis methods for model-information interfaces between hull structure design and outfitting design, and a technical application for manufacturing phases reflecting the pipe support pad and angle item automatically. The existing information procedure of pipe support pad and angle system processes information using drawing without model specification. Outfitting design team directly distributes drawings to the shop floor then manual-based marking and installation work are conducted refer to the distributed drawings. As a result, this process has become time consuming and causes problems in the productivity and quality improvement due to the rework caused by omitted or incorrect marking. The pipe support pad and angle marking is a method that automatically updates model information to hull structure design using sets of data that analyse the generated model in outfitting design processes. Therefore, this approach provides an efficient solution through design references without manual activities such as a reflection of hull structure design, cutting process, numerical control work, and dimension measurement and marking. The conversion of a method from the existing procedure based on manual marking to the reflective and automatic approach would have enabled to proceed installation work without manual activities for the measurement. Therefore, this research study proposes an efficient approach using pre-data analysis of model information interfaces between design and manufacturing phases to improve productivity during construction for shipbuilding.

• Tunnel and Underground Space
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• v.2 no.1
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• pp.102-115
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• 1992

Blasting operations associated with rock excavation work may have an environmental impact in nearby structures or human beings. With the increase of construction work in urban areas, vibration problems and complaints have also increased. In order to determine the optimum design parameters for safe blast, it is essential to understand blast mechanism, design variables involved in blast-induced damage, and their effects on the blasting results. This paper deals with the characteristics of ground vibrations, air blast and fly rock caused by blast, including the general method of establishing the vibration predictors, and damage criteria suggested by various investigators. The results of field measurements from open pit mine and tunnel construction work are discussed. Basic concepts of how to design blast parameters to control the generation of ground vibrations, air blast and fly rock are presented.