• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.6
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• pp.29-35
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• 2005

This paper presents the basic quench protection idea for the HTS(High-Temperature Superconducting) cable. In Korea power system, the transfer capability of transmission line is limited by the voltage stability, HTS cable could be one of the countermeasure to enhance the transfer limit with its higher current capacity and lower impedance[1]. However, the quench characteristic makes not only HTS cable to loss its superconductivity, but also change the impedance of the transmission line and power system operating condition dramatically. This pheonominum threats HTS cable safety as well as power system security, therefore a proper protection scheme and security control counterplan have to be established before HTS cable implementation. In this paper, the quench characteristics of HTS cable for the fault current based on heat balance equation was established and a proper protection method regarding conventional protection system was suggested.

• 유체기계공업학회:학술대회논문집
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• 1998.12a
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• pp.151-158
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• 1998

The screw compressor is first invented by a Swedish engineer, Alf Lysholm in 1934. Since then, the development of the screw compressor idea for industrial applications has been continued by the Swedish research organization Svenska Rotor Maskiner, often identified by its initials SRM. The first industrial application of the machine was marketed as an air compressor in the 1950s. The screw compressor which is a positive displacement type compressor compresses gases by the rotation of a pair of mating rotors. The operation of this compressor is entirely rotary and dynamically in balance. Also there is no need for any valve mechanism and there exists less mechanical wear between the parts compared to the conventional reciprocating compressors. Due to these prominent features, the screw compressor has been rapidly spread into the air compressor market replacing the conventional reciprocating compressors and begun to be applied as a refrigerant compressor since the 1960s. In this work, the operation principle of the screw compressor is described in brief and the major design parameters affecting the compressor performance are classified. The international research trend in screw compressor development is introduced and the current situation in our country is described.

• Journal of Korean Society for Quality Management
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• v.33 no.3
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• pp.126-134
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• 2005

This paper proposes a selectively cumulative sum(S-CUSUM) control chart for detecting shifts in the process mean. The basic idea of the S-CUSUM chart is to accumulate previous samples selectively in order to increase the sensitivity. The S-CUSUM chart employs a threshold limit to determine whether to accumulate previous samples or not. Consecutive samples with control statistics out of the threshold limit are to be accumulated to calculate a standardized control statistic. If the control statistic falls within the threshold limit, only the next sample is to be used. During the whole sampling process, the S-CUSUM chart produces an 'out-of-control' signal either when any control statistic falls outside the control limit or when L -consecutive control statistics fall outside the threshold limit. The number L is a decision variable and is called a 'control length'. A Markov chain approach is employed to describe the S-CUSUM sampling process. Formulae for the steady state probabilities and the Average Run Length(ARL) during an in-control state are derived in closed forms. Some properties useful for designing statistical parameters are also derived and a statistical design procedure for the S-CUSUM chart is proposed. Comparative studies show that the proposed S-CUSUM chart is uniformly superior to the CUSUM chart or the Exponentially Weighted Moving Average(EWMA) chart with respect to the ARL performance.

• Fashion & Textile Research Journal
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• v.16 no.1
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• pp.160-166
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• 2014

Patent and utility indicate international competitiveness in the knowledge-based society of the $21^{st}$century where both the quantity and quality of the nation's scientific intelligence and innovative technology represent key criteria to evaluate its strength. Thus, discerning the trends of patents is inevitable for further development. This research is centered on apprehending the technological current of the functional clothing of Korea, through an analysis of patents and utility models. The number of patent applications in Korea was low until the mid-1990s. However, it began to grow rapidly in the 2000s and the number of patents surpassed the number of utility starting in 2006. The technological level of invention in this field has been turned into a higher level. The IPC code with the strongest application was the field related to temperature controllable clothing (A41D 13/005), followed by surgeon or patient apparel related fields (A41D 13/12), and reflective or luminous safety devices (A41D 13/01).The main technological idea was to give functionality that could protect the human body from various hazards and represents the goal of various applied techniques. About 66% of domestic patent applications belong to individuals; however, the proportion of corporate or institutional applications(including universities) remains poor. Consequently, more systematic and long-term support for research on patents is required.

• Journal of The Korea Institute of Healthcare Architecture
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• v.2 no.3
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• pp.71-81
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• 1996

The existing domestic and foreign elderly nursing homes, with 50 beds or more, are selected and examined according to user interview, and document analysis to understand the facts about the elderly nursing homes. The location of domestic nursing homes is limited to the region of Seoul and Kyunggi province. The scope of research is focused on the plans, area compositions, equipments and relations with public spaces - wandering paths, bathrooms and toilets. The content of research, based on the collected data discribed above, includes the search for architectural idea and the examination of typological differences among plans. The research is performed as followes. 1) description of research objectives. 2) examination of problems associated with the elderly. 3) understanding of systems and plans of domestic and foreign nursing homes. 4) performance of case study, derivation of design criteria for architectural planning, and suggestion of several adjustable alternatives for public spaces.

• Steel and Composite Structures
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• v.15 no.4
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• pp.379-397
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• 2013

Conoidal shells are doubly curved stiff surfaces which are easy to cast and fabricate due to their singly ruled property. Application of laminated composites in fabrication of conoidal shells reduces gravity forces and mass induced forces compared to the isotropic constructions due to the high strength to weight ratio of the material. These light weight shells are preferred in the industry to cover large column free open spaces. To ensure design reliability under service conditions, detailed knowledge about different behavioral aspects of conoidal shell is necessary. Hence, in this paper, static bending, free and forced vibration responses of composite conoidal shells are studied. Lagrange's equation of motion is used in conjunction with Hamilton's principle to derive governing equations of the shell. A finite element code using eight noded curved quadratic isoparametric elements is developed to get the solutions. Uniformly distributed load for static bending analysis and three different load time histories for solution of forced vibration problems are considered. Eight different stacking sequences of graphite-epoxy composite and two different boundary conditions are taken up in the present study. The study shows that relative performances of different shell combinations in terms of static behaviour cannot provide an idea about how they will relatively behave under dynamic loads and also the fact that the points of occurrence of maximum static and dynamic displacement may not be same on a shell surface.

• Structural Engineering and Mechanics
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• v.74 no.4
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• pp.481-494
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• 2020

In this paper, a probability-based procedure to evaluate the performance of existing RC structures exposed to seismic and fire actions is presented. The procedure is demonstrated with reference to an existing old school building, located in Italy. The vulnerability assessment of the building highlights deficiencies under both static and seismic loads. Retrofit operations are designed to achieve the seismic safety. The idea of the work consists in assessing the performance of the existing and retrofitted building in terms of both the seismic and fire resistance. The seismic retrofit and fire resistance upgrading follow different paths, depending on the specific configuration of the building. A good seismic retrofit does not entail an improving of the fire resistance and vice versa. The goal of the current work is to study the variation of response due to the uncertainties considered in records/fire curves selection and to carry out the assessment of the studied RC structure by obtaining fragility curves under the effect of different records/temperature. The results show the fragility curves before and after retrofit operations and both in terms of seismic performance and fire resistance performance, measuring the percent improving for the different limit states.

• Journal of Biomedical Engineering Research
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• v.32 no.1
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• pp.32-36
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• 2011

The insufflators in endoscopic surgery supply carbon dioxide to make the air-filled cavity in the abdomen. It contains many kinds of pneumatic and electronic parts and they are connected with the air tubes and electrical wires. The printed circuit boards (PCB) perform wiring, holding and cooling tasks in electronic systems. In this study, the PCB is used as the air channel for insufflators to decrease the cost, volume, and the malfunction according to aging of the device. Three layers of PCB made of FR4 are combined with prepreg as adhesive which has the internal airway channel according to the design. By mounting the pressure sensors and valves, the PCB based fluidic system is implemented. After calibration of flow sensor, the flow rate of the gas also can be measured. The climate test, temperature test, and biocompatibility test showed this idea can be used in insufflators for laparoscopic surgery.

• Korean Journal of Artificial Intelligence
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• v.4 no.1
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• pp.8-10
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• 2016

These days, citizens have a lot of ways to get access to IT. In the past, they tended to neglect IT that was thought to be difficult. But, currently, everyone can manufacture and get access not only software but also hardware when he has an idea. Arduino is used. Rinnai had recently released new product named Smart Sensor Range. Safe consumer who gave priority to the safety made new trend gave attention to fire prevention and smart sensor range. The ones who buy gas range prefer safety to economic advantage and/or fire power. The safety system does not always prevent fire accident. This study makes design and produces alarm that perceives temperature of pot when boiling. Not only temperature sensor but also alarm sensor was used to make alarm of boiling water and to give convenient living life. The arduino can be used at practical life to make products for various kinds of people. The invention can give convenience to housewives at kitchen, children and many persons making use of gas range. Another function can be added to develop. This arduino can develop a lot of products by using the study and other designs.

• Korean Journal of Human Ecology
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• v.12 no.5
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• pp.755-766
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• 2003

The surrealism for the revelation of the unconscious realms shares the inner world of mentality with modern fashion display for the visual expression of sensation each other. The analysis of the influence which automatism technique of surrealism exerts on fashion display showed as follows : 1) The automatism technique elevated the dramatic effect of the sales room by scraping the perspective, or the principle of visual arts. 2) It maximized the effect of subject of the display by coinciding surrealism with realism. 3) The technique which distorts the things heralded the strong message to customers by letting them keep away from the fixed idea. 4) Humorous expression of display brought about the effect of sales stimulation by giving astonishment, shock and exaggeration. 5) Expression of surrealism and realism caused customers to feel shock, illusion, fantasy. 6) The automatism technique expressed the high-tech image, and free expression by revealing the diversity of subject. 7) Display hinted from nature satisfied the mental desire of the human beings to be assimilated with nature. The formative characteristic presented the new possibility of combination of display with arts through the avant-garde sensation. Sale's room, or the marketing space was to be sublimated to three dimensional art space, which enhanced the image of sale's room, furthermore meeting the demand of moderner's lifestyle.