• Title/Summary/Keyword: 김기열

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Electromagnetic Interference Shielding Effectiveness of Hybrid Conductive Fabrics (하이브리드 전도성 직조섬유의 전자파 차폐효과)

  • Han, Gil-Young;Kim, Ki-Yeol;Yun, Tae-Soon
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.14 no.2
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    • pp.81-86
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    • 2015
  • This study investigated electromagnetic interference (EMI) shielding effectiveness (SE) of hybrid conductive fabrics. The coaxial transmission line method was used to measure the EMI Shielding effectiveness of the conductive fabrics. We designed and constructed a measuring system, consisting of a network analyzer and a device that serves as a sample holder and at the same time as a transmission medium of incident electromagnetic waves. The measurements of SE were carried out in a frequency range from 100 MHz to 2 GHz. The results of the EMI shielding experiments showed that the maximum electromagnetic shielding effectiveness (EMSE) values of sandwich type C/A/C (carbon fiber sheet/aluminum foil tape/carbon fiber sheet) and C/Ni/C (carbon fiber sheet/magnetic shielding foil/carbon fiber sheet) samples were 55 dB and 113 dB, respectively, at a frequency of 1.9 GHz.

Middle and High School Student' Knowledge Level on First Aid. (중 . 고등학생 응급처치 지식수준에 관한 실태 조사)

  • 홍경용;남철현;최상복;위광복;김기열
    • Korean Journal of Health Education and Promotion
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    • v.18 no.3
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    • pp.77-88
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    • 2001
  • This study was conducted to examine middle and high school students' knowledge level of first aid, health promotion, and safety. Data were collected from 1.165 students from March 6, 2000 to April 4, 2000. The results of this study are summarized as follows. 1. 80.1% of the respondents felt the necessity of first aid. The sources of information about methods of first aid were school (43.9%), mass media (15.6%), and self-study (10.5%). 30.0% of them never learned the methods of first aid. 2. In the case of obtaining information on first aid through mass media, 58.2% of them got it from TV. 7.3% of them obtained it from magazines, while 5.8% of them got it from newspapers. According to their viewpoints of adequate time to teach the methods of first aid, 38.6% of them thought that the methods had to be taught in the primary school and 25.2% of them thought that they had to be taught in the kindergarten. 24.9% of them replied that the methods had to be taught in the middle school, while 11.3% of them replied that they had to be taught in the high school. 3. The points for knowledge of first aid were 98.29:t20.91 on the basis of 150 points (65.5 points on the basis of 100 points). The points showed significant differences in the variables of sex, education level, numbers of siblings, parents' education level, and guardian's occupation.

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Design of the Feedback Controller of Direct Satellite Broadcasting Antenna for Vehicle (이동체용 직접위성방송 수신 안테나의 궤환 제어기 설계)

  • Kim, Ki-Yeoul;Park, Chong-Kug
    • Proceedings of the KIEE Conference
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    • 2001.11c
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    • pp.53-56
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    • 2001
  • In this paper we discuss a direct satellite broadcasting system for vehicle. The proposed satellite-steering algorithm and controller based on it are designed for a communication and broadcasting system which uses the Mugungwha satellite. The Mugungwha satellite that the proposed system should steer is a geostationary orbit device. The satellite-steering algorithm computes azimuth and elevation with reference to a stationary point on earth. This is extended to a real satellite steering algorithm that considers position and attitude. Real moving position and attitude are represented by latitude, longitude, roll, pitch and yaw. To apply these five pieces of information to the reference satellite steering algorithm, we introduce Euler's degree coordinates that express independently the rotation of each axis relative to an axis. There are two ways a basic algorithm of the antenna of a vehicle can track and orient to satellite. One way is a feedback loop method for broadcasting gain, while the other is a feedback loop method for position and attitude of a vehicle. In the present paper, we design a controller of satellite broadcasting system for a vehicle using an algorithm that combines the two methods. We performed a simulation and experiment to prove effectiveness.

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Development of Violin Self-Training Algorithm using Fuzzy Logic (퍼지제어를 이용한 바이올린 연주 연습 알고리즘 개발)

  • Min, Byung-Cheol;Kim, Dong-Han;Kim, Yoon-Hyuk;Kim, Ki-Yeoul;Park, Chong-Kug
    • Journal of the Korean Institute of Intelligent Systems
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    • v.19 no.4
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    • pp.550-555
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    • 2009
  • A violin plays an essential role among string instruments. It has an extremely strong expressive power that can be conveyed through beautiful timbre when played correctly. However, a beginner who attempts to play the violin will be most likely to face difficulties in placing his or her fingers on a specific point of the fingerboard or in bowing the violin on a specific string. In order to resolve this difficulty, the database of a professional violinist's bowing skills were inserted beforehand. By doing so, a beginner can emulate professional's violin by comparing his playing with the constructed database that is programmed in the computer. Accordingly, the results are displayed on the monitor after being evaluated by the performance evaluation function using a fuzzy logic.

Development of a New Process for Welding a WC Layer to the Round Surface of a Plain Carbon Steel (초경접합 신공법 개발)

  • 박우진;김기열;이범주;조정환;박채규
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1999.11a
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    • pp.257-262
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    • 1999
  • The economic loss arisen from the abrasion wear have been increasing at every industrial field. To reduce the economic loss we developed a new process, which is named MAHa process(Metallic Adhesives for HArdening). MAHa process is a process to weld tungsten carbide(WC) to the surface of a plain carbon steel so that it may stay longer under the severe abrasive environment. The depth of the WC layer ranges from 0.5 mm to 5 m. Compared with the conventional technology, arc-augmented welding which bonds WC on the flat surface only, MAHa process has the merits that it can make a robust WC layer on the round or wave- shaped surface also. How to turn the WC powder into a flexible mat is the key technology of the MAHa process. We invented new polymer materials to accomplish such a goal and both the MAHa process and the invented materials were applied for patents. For the application, the inner wall of elbow of Concrete Pump Truck(CPT) was maharized(MAHa process-treated) and the new WC layer on the inner wall was made successfully. The elbow was equipped to a CPT.

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Comparative Evaluation of Albedo Distribution according to Administrative Boundary Using MODIS Products (MODIS 영상을 이용한 행정구역별 알베도 분포 비교평가)

  • Kim, Ki-Youl;Um, Jung-Sup
    • Journal of Environmental Impact Assessment
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    • v.21 no.2
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    • pp.265-277
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    • 2012
  • This paper is primarily intended to present quantitative evidences for land surface albedo difference among seven metropolitan cites in South Korea. An empirical study for experimental sites was conducted to confirm how a standard MODerate Resolution Imaging Spectroradiometer (MODIS) instrument offers the viable method of measuring and comparing the regional heterogeneity of albedo among administrative districts. The metropolitan cities like Seoul located in dense building environment do result in much lower albedo than those exposed in much more sub-urban surface (e.g KwangJoo). These experimental results indicate that an urban surface such as building and road is a crucial explanatory variable for lower albedo. It is confirmed that the urban surface such as building and road could be employed as a proxy of the lower albedo burden in the metropolitan area. It is anticipated that this research output could be used as a valuable reference to confirm the potential of introducing the new concept of "administrative districts specific albedo management" to support more scientific and objective decision-making in the process of GHG (Greenhouse Gas) reduction project.

A Study on Thermal Insulator Effect for Structure Design of Internal Support on Cryogenic Vessel (단열재가 극저온 용기의 내부지지대 구조설계에 미치는 영향)

  • Kim, Doo-Ho;Ji, Hyun-Jin;Kim, Ki-Youl;Cho, Sung-Baek
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.3
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    • pp.524-531
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    • 2011
  • The cryogenic vessel, storing a liquified solutions as LOX and $LN_2$, consists of a external vessel, internal vessel, thermal insulator and internal support. The internal support should be satisfied with mechanical strength not only to support weight of internal tank but also to maintain uniform space between external and internal tank in spite of external mechanical shock. However, excessive structure design of internal supports is able to increase the amount of heat conduction and the rate of vaporization. The thermal insulator, filled with space between a external and internal vessel, reduces the rate of heat transfer and guarantees the standing time of cryogenic vessel. Especially powder type of insulator has low thermal conductivity and reduce the specification of structure design. In order to evaluate the effect of insulator on structure design, the experiment set-up simulated cryogenic vessel was tested in shock environment according to thermal insulator. As a result, the behavior of internal support under external shock was understood and the design criteria was able to be suggested.

Fuzzy Controller Design of 2 D.O.F of Wheeled Mobile Robot using Niche Meta Genetic Algorithm (Niche Meta 유전 알고리즘을 이용한 2자유도 이동 로봇의 퍼지 제어기 설계)

  • Kim Sung-Hoe;Kim Ki-Yeoul
    • The Journal of Information Technology
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    • v.5 no.4
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    • pp.73-79
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    • 2002
  • In this paper, I will propose the Niche-Meta Genetic Algorithm that has a multi-mutation operator for design of fuzzy controller. The gene in the proposed algorithm is formed by several parameters that represent the crossover rate, mutation rate and input-output membership functions. The optimization of fuzzy membership function is performed with local search on sub-population and the optimal structure is constructed with global search on total-population. The multi-mutation is selected under basis of the result of local evolution. A simulation for 2 D.O.F wheeled-mobile robot is showed to prove the efficiency of the proposed algorithm

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Actinomycosis on Left Submandibular Area -A case report- (두경부에 발생한 방선균병(Actinomycosis)의 치험 1례)

  • Hong, Jung-Soo;Kim, Ki-Yeul;Choi, See-Ho;Seul, Jung-Hyun;Hwang, Hyenog-Ki;Lee, Chung-Ki
    • Journal of Yeungnam Medical Science
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    • v.8 no.1
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    • pp.231-237
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    • 1991
  • Actinomycosis is a chronic suppurative and granulomatous bacterial infection characterized by contiguous spread, abcess formation and sinus tract formation. There are four clinical forms according to the lesional site, as 1) cervicofacial, 2) thoracic, 3) abdominal, and 4) disseminated form. Recently, we experienced a case of 54 year-old patient with left mandibular actinomycosis. The pathognomonic findings of actinomycosis is sulfur granule with multiple filaments in Gram-stain and the treatment of actinomycosis is surgical excision of mass or sinus tract with massive antibiotics(esp. Penicillin) therapy for 6 to 12 months.

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Factors Influencing Closeness in Family with an Elderly Member (노인의 가족화목도와 관련요인)

  • Hong, Se-Young;Nam, Chul-Hyun;Kim, Gi-Yeol;Wee, Kwang-Bok;Shim, Kyu-Bum;Bae, Hyang-Sun;Ko, Jae-Ok
    • Journal of Society of Preventive Korean Medicine
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    • v.12 no.2
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    • pp.85-100
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    • 2008
  • The purpose of this study was to determine factors influencing family closeness in family with an elderly members. The study was conducted with 1,904 subjects during 3 months from 1st March to 30,May. 2006. The results were as follows. 1. Family closeness of subjects was significantly associated with age, sex, marital status, monthly allowance, education level, occupation, the number of family members living together, health state, stress, and emotional conflict with children. 2. Emotional conflict with children was significantly associated with age, sex, religion, the number of family members living together, occupation, health state, stress, family closeness. 3. Stress was significantly associated with age, sex, religion, the number of family members living together, occupation, stress, family closeness. Finaly, Family closeness in family with an elderly member was positively related to family type(living with a spouse), monthly allowance, occupation but negatively related to emotional conflict with children and stress levels. The government, social service units and experts need to pay more attention to factors influencing family closeness and devise effective policy and programs for healthier family relations.

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