• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.9
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• pp.201-208
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• 2013

In this paper, we studied on improvement for radiated EMI of USB power line of cable. it is made by using wireless video access point system for confirming the phenomenon of radiated EMI from cable. then, we make sure that the limit exceed through the initial measurement of radiated EMI limit criteria in comparison to about 3 [dBuV/m]~15 [dBuV/m]. after that we confirmed the resonance in power line of cable through measurement of s-parameters. so, we confirmed the relation radiated EMI and power line of cable resonance and we reduced radiated EMI in power line of cable through a capacitor and low pass-band filter using the technique of power networks management. in conclusion, we suggested how to reduce power line of cable resonance applied for the improved method. and we confirmed that suggested reduction method is suitable through testing radiated EMI. the result of radiated EMI reduction limit criteria 40[dBuV/m]~47[dBuV/m] in comparison to about 3 [dBuV/m]~20 [dBuV/m].

• Journal of Korean Society of Transportation
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• v.23 no.2
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• pp.75-82
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• 2005

To relieve congestion in the current system of intercity transportation, the Korea decided in 1990 to construct a high-speed railroad between Seoul and Busan and it is now in operation. This new mode of transportation significantly cut travel time between major cities and a trip from Seoul to the southeastern port of Busan. Since the KTX opening, average daily passenger numbers on both the Gyeongbu and Honam lines have increased about 1.3 fold over 2003 levels. As of December 2004, the KTX trains are carrying about 81,000 people a day. On KTX routes, the daily number of airline passengers dropped. Express long-distance bus traffic also dropped by 20% to 30%, while that on short-distance routes (100km or less) increased by about 20%. These figures clearly indicate that the Korean transportation network is becoming railroad-centric. However, the number of KTX passengers is fewer than anticipated possibly due to the Korean economic downturn and the operation of the KTX will leave many existing Saemaul and Mugunghwa train sets idle, which will be put into operation for areas, not covered by the KTX. When all the existing major lines have been electrified, more high-speed rail services will be phased in using direct connections to maximize operational efficiency. And also, the dual management by KTX and conventional rail will be regarded as the promotion of the benefit of the public.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.264-264
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• 2017

국외의 상수도 원격검침 시스템 내 데이터 전송방식은 도시 규모, 계량기의 밀도, 전력공급 여부 및 통신망의 설치 여부 등을 종합적으로 고려하여 결정되었다. 대부분의 스마트워터미터 제조업체들은 계량기의 부호기가 공급하는 판독 내용(데이터)을 전송할 검침단말기와 근거리 통신망(neighborhood area network)을 연계하여 개발 및 판매하였으며, 자체 소유 통신 프로토콜을 사용하여 라디오 주파수(RF) 통신 기술을 사용하고 있다. 광역통신망(wide area network)의 경우, 노드(말단의 계량기 및 센서)들과 이에 연결된 통신망 들을 포함한 네트웍의 배열이나 구성이 스타(star), 메쉬(mesh), 버스(bus), 나무(tree) 등의 형태로 통신망이 구성되어 있으나, 스타와 메쉬형 통신망 구성형태가 가장 널리 활용되는 것으로 조사되었다. 시스템 통합운영관리 업체들인 IBM, Oracle, Itron 등은 용수 인프라 관리 또는 통합네트워크 솔루션 등의 통합 물관리 시스템(integrated water management system)을 개발하여 현장적용을 하고 있으며, 원격검침 시스템을 통해 고객들의 현재 소비량과 과거 누적 소비량, 누수 감지 서비스 및 실시간 요금 고지 등을 실시간으로 웹 포털과 앱을 통해 제공하고 있다. 또한, 일부 제조업체들은 도시 용수공급/소비 관리자가 주민의 용수사용량을 모니터링하여 일평균 용수사용량 및 사용 경향을 파악하고, 누수를 검지하여 복구 및 용수 사용 지속가능성 지수를 제시하고, 실시간으로 주민의 용수사용량 관련 데이터를 모니터링하여 용수공급의 최적화를 위한 의사결정지원 서비스를 용수공급자에게 제공하고 있다. 최근에는 인공지능을 활용해 가정용수의 용도별(세탁용수, 화장실용수, 샤워용수, 식기세척용수 등) 사용량 곡선을 패터닝하여 profiling 기법을 도입해, 스마트워터미터에서 용수사용량이 통합되어 검지될 시 용수사용량의 세부 용도별 re-profiling 기법을 도입하여 가정용수내 과소비되는 지점을 도출 후 절감을 유도하는 기술이 개발 중이다. 또한, 미래 용수 사용량 예측을 위해 다양한 시계열 자료를 분석하는 선형 종속 모형(자기회귀모형, 자기회귀이동평균모형, 자기회귀적분이동평균모형 등)과 비선형 종속 모형(Fuzzy Logic, Neural Network, Genetic Algorithm 등)을 활용한 예측기능이 구축되어 상호 비교하여 최적의 용수사용량 예측 도구를 제공되고 있다.

• Journal of vocational education research
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• v.35 no.6
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• pp.21-38
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• 2016

The purpose of this study is to analyze an experience of field practice perceived by vocational teachers. Data for analysis were collected from 689 vocational teachers who participated in the training at the Center for in-service teacher education in the School of Agriculture and Life Sciences, Seoul National University and at the Center for in-service teacher education of Chungnam National University. After screening, 685 responses were used in the analysis. As a result, it turned out that only 112 vocational teachers(16.5%) participated in the field practice for more than 4 weeks when they were in pre-service education. However, vocational teachers seemed to perceive that experience of field practice was generally required in pre-service education(average 4.07). In-depth questionnaire was conducted on 143 respondents who replied that they participated in field practice program for more than 4 weeks and those who participated in the program for less than 4 weeks but completed the paperwork. Most of vocational teachers who participated in field practice were placed in small and medium sized enterprises, stayed at home or relatives' home and commuted by the bus or subway. In this research, 34.8% of the vocational teachers who participated in field practice received financial compensation and 80.3% of the teachers got credit recognition. The perception of satisfaction on field practice program was found to be moderate(average 3.51).

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.2
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• pp.171-187
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• 2023

Objectives: Aircraft cabin cleaning work is characterized by being performed within a limited time in a narrow and enclosed space. The objective of this study was to evaluate the exposure levels to dust, ultra fine dust(PM2.5) and black carbon(BC) among aircraft cabin cleaners. Methods: Active personal air sampling for respirable dust(n=73) and BC(n=47) was conducted during quick transit cleaning(cabin general and vacuum-specific) and seat cover replacement and total dust and PM2.5 were area-air-sampled as well. Also, size distribution of particle was identified with the cleaning workers targeted. Dusts were collected with PVC filters using gravimetric analysis. The concentration of PM2.5 and the particle size distribution were measured with real-time direct reading portable equipment using light scattering analysis. The concentration of BC was measured by aethalometer(filter-based real-time light absorption analysis instrument). Results: The geometric mean of respirable dust was the highest at vacuum cleaning as 74.4 ㎍/m³, following by replacing seat covers as 49.3 ㎍/m³ and cabin general cleaning as 47.8 ㎍/m³ . The arithmetic mean of PM2.5 was 4.83 ~ 9.89 ㎍/m³ inside the cabin, and 28.5~44.5 ㎍/m³ outside the cabin(from bus and outdoor waiting space). From size distribution, PM_2.5/PM₁₀ ratio was 0.54 at quick transit cleaning and 0.41 at replacing seat covers. The average concentration of BC was 2~7 ㎍/m³, showing a high correlation with the PM2.5 concentration. Conclusions: The hazards concentration levels of aircraft cabin cleaners were very similar to those of roadside outdoor workers. As the main source of pollution is estimated to be diesel vehicles operating at airports, and it is necessary to replace older vehicles, strengthen pollutant emission control regulations, and introduce electric vehicles. In addition, it is necessary to provide as part of airport-inftastructure a stable standby waiting space for aircraft cabin cleaners and introduce a systematic safety and health management system for all workers in the aviation industry.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.4
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• pp.76-88
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• 2014

The purpose of this study is to derive landscape characteristic elements of agricultural and fishery heritage and to classify landscape characteristic elements of Cheongsando designated as Korean agricultural and fishery heritage No.1 as well as a Globally Important Agricultural Heritage System (GIAHS). Additionally, this study was conducted to suggest priority for conservation and management of Cheongsando by grasping differences between factors which visitors deem as important and satisfying. To implement this study, the literature review was written, an on-site survey to derive landscape characteristic elements of Cheongsando and a survey on importance and satisfaction of landscape characteristic elements of Cheongsando were conducted, and reliability analysis, descriptive statistical analysis and IPA analysis were performed using SPSS 20.0. The results are as follows: The analysis showed the factors requiring persistent efforts in the first quadrant are the rape flower garden, the sea, green barley field, flat stone paddy field, breakwater and lighthouse, abalone farms, stone houses, thatched houses, a coastal road, the slow road, Stonewall Walkway of Seongseo Village, and residents' agricultural behaviors. The analysis showed the factors needing intensive management strategies in the second quadrant are the surrounding mountain area, dock, Docheong Harbor, vessels, fish market, Doksari stone wall, garish-roofed farm villages, excursion school to a slow island, pension and cafe, bus stop, shade trees, Raw Fish Street, the beach and the filming site. Analysis indicated that the factors needing management control in the third quadrant are the pine grove, the beach, tidal mudflat, the garlic fields, vinyl greenhouses, grain drying yard, sea mustard drying yard, heritage center, Choboon, Dangri exorcism, the market place, residents' fishery behaviors, residents' industrial behaviors, residents' ordinary behaviors, visitors' behaviors that visiting the dock, visitors' behaviors that walking the slow road, visitors' behaviors that eating and shopping for specialties, visitors' behaviors that experiencing agriculture and fishery. Excessive effort factors in the fourth quadrant were not derived.

• Journal of agricultural medicine and community health
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• v.18 no.1
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• pp.77-91
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• 1993

This study was conducted to assess health medical center utilization pattern and its related factors among the rural inhabitants for the purpose of contribution to establishment of health medical center institutions. A questionnaire survey was carried out for object of 3,754 population of three primary school and three middle school student's parents (total 832 household) in Kyungbook Ulchin Gun rural area from 24 to 28 September, 1990. The summarized result are as follows, Respondents are 60.3% in male, 39.7% in female and 30-40s 81.3% in age, high school graduates 40.3% in education level and a regional medical insurance scheme in 44.1% in forms of health insurance. Recognition for health medical center was showed higher according to high educational, high income level, and short distance for location of health medical center of respondents (p < 0.01). Recognition for health medical center services was showed higher about care of medicaid in medical treatment services and higher preventive vaccination in health prevention services by respondents. Utilization rates of health medical center by out-patient care and preventive care service were 11.1 and 4.5 per 100 persons by year, but admission utilization rate was 34.6 per 10.000 persons by year. Motivations of health medical center utilization were showed a good care(45.7%), a good drugs(45.2%), and nearby health medical center(42.9%). In comparison health service levels of health medical center with general clinic was better (16.3%), similar(38.7%), 7(19.0%), and worse(19.0%) in view of health medical center utilizators. Inconvinience about health medical center utilized was the most higher longtime waiting, the next was limited utilization times. Transportation utilited were on foot(55%), by bus(35.5%), and so on. As mentioned above, there are many inhabitants who less understanding and less acknowledgement about health medical center and even mistake health center for health medical center. Therefore, there must be more information about health medical center. For higher utilization of health medical center, there must be considered expansion of health equipment, facilities, accomplishment with reinforcement of health staffs and efficiency management.

• Journal of Korean Society of Archives and Records Management
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• v.1 no.1
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• pp.201-230
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• 2001

Conserving the recored cultural inheritance is actually the duty of all of us. Above all, the management and conservation of archives and documents is up to archivists who have technical knowledge about archival science. Archivists have to not only conserve archives and documents but also carry out classifying and appraising them in order to define them as current historic ones. The fundamental education about archival science is made up of history and law. Because Archive is the organisation which manage archives and documents produced by legal and administrative actions. Although there are still arguments about technical knowledge and degree archivists have to acquire, most of them prefer the studies related with history and emphasize legal studies to be the general boundary of archivits' ideology and trust. The training course about conservation of archives is conducted in about 9 National Archives of Torino, Milano, Venezia, Genova, Bologna, Parma, Roma, Napoli, Palermo. The training course in 19th was mostly based on the lectures of Phaleography, Diplomatics. There were not the education about archival science yet. Toward the end of 19th and 20th, people stressed the most basic subject in the training course of National Archive was not Phaleography and Diplomatics but archival science. The goal of archival science is to study the institution and organisation transferring archives and documents to Archive. And also it help archivists not wander about with ignorance of organisational and original procedures and divisions but know exactly theirs works. Like this, the studies on institution and organisation have got in the saddle as a branch of archival science since a few ten years. While archival science didn't evoke sympathy among people and experienced the tedious and difficult path in italy and other countries, Archive was managed by experts of other branches. As a result, there were a lot of faults in Archival Science. Specializing training course for Italian archivists came into being under the backdrop of Social Science Institute of Roma National University in 1925. The archival course of universities accomplished by the studies of history, law and economy. And such as Eugenio Casanova and Giorgio Cencetti were devoted archival science was abled to settle down in national archive. The training course for experts of 'archival science, 'Phaleography and Diplomatics' in National Archive of Bologna(Archivio di Stato di Bologna) is one of courses conducted in 17 National Archives in italy. This course is gratuitous and made up of 8 subjects(Archivistica, Paleografia, Diplomatica, Storia dell' Archivio, Notariato e documenti privati, istituzione medievale, istituzione moderna, istituzione contemporanea) students have to complete for two years. Students can receive the degree through passing twice written exam and once oral test. After department of Culture and education finally puts the marks of students, the chief Nationa Archive of Bologna confer the degree of 'archival science Phaleography and Diplomatics' on students passing the exams. This degree authenticates trainees' qualification which enables him to work at the archive in province, district and administrative capital city and archive of comunity and so on. Italian training course naturally leads archivists to keep in contact with valuable cultural inheritance through training in Archive. And it shows the intention to strengthen the affinity with each documents in the spot of archival management before training archivists. Also this is appraised as one of positive policies to conserve the local cultual inheritante in connection with the original qualitity of national archive with testify the history of each region. Traning course for archivist in Italy shows us the way how we have to prepare and proceed it. First, from producing documents to conserving than forever there has introduced 'original order that is to say a general rule to respect the first order given at the time producing documents'. Management of administrative documents is related consistently with one of historical documents. Second, the traning course for archivist is managing around 17 national archives. because italian national archive lay stress not or rducation of theory bus on train for archivest working in the first time of archival science. Third, diplomatics and phaleography for studies about historical document support archives. Forth, the studies on history id proceeding by cooperation between archivist and historian around archive. How our duties is non continuinf disputer who has to conserve and manage document and archives, but traing experts who having ability, vision and flexible thought, responsibility about archivals.