고등학교 공통과학 학습을 위한 멀티미디어 자료 구축

김재현,이희복,김현섭,김희수,박종욱,박현주,Kim, Jae Hyun,Lee, Hee Bok,Kim, Hyun Sub,Kim, Hee Soo,Park, Jeong Wok,Park, Hyun Ju 대한화학회 2000 대한화학회지 Vol.44 No.3

This study was designed to develop learning materials of multimediafor general science instruction of high school.this learning material was made of HTML record for each middle unit according to the general science curriculum, and was included a variety of Ietter, graph, picture, drawing, animation, and other moving image materials. And it was composed five coursewares:Content, Dictionary, Science Story,lmage Material, and Questions.The learning material is uploaded an internet website under Science Education Research Institute of Kongju National University (http://science.kongju.ac.kr), and also is provided to a CD-ROM title. 본 연구는 고등학교 공통과학 학습을 위한 멀티미디어 자료를 구축하는데그 목적을 두었다.공통과학 교육과정을 기초로 하여 문자 자료, 도표, 그림, 사진, 애니메이션, 동영상 및 음성 자료 등을 HTML 사용하여 멀티미디어 학습 자료를 개발하였다. 멀티미디어 학습 자료의 구성은 내용, 용어사전, 과학이야기, 영상자료, 그리고 질문의 다섯 분야로 나뉜다. 개발된 멀티미디어 자료는 공주대학교 과학교육연구소 홈페이지 (http://science.kongju.ac.kr)에 올려놓았으며, 또한 CR-ROM으로 제공된다.

영산강 하구지역 점토의 침하특성 고찰

김재현,김동범,이현웅,박성수,Kim, Jae-Hyun,Kim, Dong-Beom,Lee, Hyun-Wung,Park, Sung-Su (사)한국토질및기초기술사회 2006 기술발표회 Vol.2006 No.-

영산강 하구지역은 현재 신도시개발이 한창 진행되고 있으며, 연약한 해성퇴적층이 15~25cm로 존재하고 있다. 연약지반 개량설계는 불교란시료를 채취하고 각종 실내시험을 통하여 지반의 토질정수를 결정한다. 본 고찰은 압밀관련 지반정수인 선행압밀하중(Pc), 압축지수(Cc), 재압축지수(Cr)를 재해석하기 위해 침하계측 결과를 이용 실내시험의 압밀 곡선과 비교 분석하였다.

디지털 치료기술 산업 육성에 따른 투자와 경제적 파급효과

김재현 ( Jae-hyun Kim ),문종윤 ( Jong Youn Moon ),장지은 ( Jieun Jang ),심정연 ( Jung Yeon Sim ),신재용 ( Jaeyong Shin ) 한국보건행정학회 2020 보건행정학회지 Vol.30 No.4

The digital treatment technology industry is one of the core fostering industries of the Moon Jae-in government along with the global trend. The purpose of this study is to compare and analyze the investment and economic ripple effect on the related industries. To this end, we used the industry-related table, which is the actual measurement data for 2015 that the Bank of Korea actually measured and released every 5 years in 2019. The digital treatment technology industry was not clearly classified within Korea’s industrial classification system, so the contents of the industry-related survey were analyzed, and the digital treatment technology industry was reclassified and then analyzed. As a result of the analysis, it was analyzed that the production induction effect of the digital treatment technology-related industry in 2015 was 1.770, the value-added induction effect was 0.875, and the employment induction effect was 19.128, which was higher than that of other industries in Korea. As a result of the analysis of the economic ripple effect (scenario 1), the production inducing effect was about 370 billion won, the added value inducing effect was about 185 billion won, and the employment inducing effect was 4,044 people. The results of this study are expected to play a large role in economic revitalization as the effect of inducing production, increasing employment, and creating added value through fostering the digital treatment technology industry is expected to play a large role in activating the economy. It is expected to play a large role in providing central medical services. Therefore, it is expected that policy support for revitalizing the digital treatment technology industry through active investment support and tax benefits from the government to foster the digital treatment technology industry is necessary.

원심모형실험용 소형 콘 개발 및 콘 선단저항치 특성에 관한 연구

김재현,김동준,김동수,추연욱,Kim, Jae Hyun,Kim, Dong Joon,Kim, Dong Soo,Choo, Yun Wook 대한토목학회 2013 대한토목학회논문집 Vol.33 No.2

현장지반의 공학적 특성을 파악하기 위한 콘 관입시험(Cone Penetration Test; CPT)은 원지반의 연속적인 강도 특성을 분석하여 다양한 지반변수를 손쉽게 획득할 수 있다는 점에서 널리 활용되고 있으며, 원심모형실험에서도 널리 활용되고 있다. 본 연구에서는 원심모형실험에서 콘선단저항치를 계측할 수 있는 직경이 10 mm인 소형 콘을 개발하고 원심모형실험에서의 적용성을 평가하였다. 개발된 콘으로 4자유도 로봇을 활용하여 원심모형 가속 상태에서 콘 관입시험을 수행하였다. 이 때, 원심가속도 수준을 4회 변화시켜 다양한 유효응력상태에서 콘 관입시험을 실험을 수행하였다. 그 결과, 얕은 관입깊이의 동일한 유효응력에서 콘 선단저항치는 g-level에 영향을 받으며, 선단저항치가 임계 깊이 도달하는 깊이는 g-level과 상대밀도가 커질수록 깊어짐을 확인하였다. 또한, 각 실험에서 임계 깊이에 도달한 선단저항치와 실내실험에서 획득한 지반물성을 이용하여 기존 경험식과 비교하였다. The standard CPT(Cone Penetration Test), which can be easily performed to investigate in-situ soil engineering properties, has been widely used. CPT are also widely being utilized in centrifuge model tests. In this study, a miniature cone with 10mm diameter was developed and its applicability in the centrifuge was evaluated. The developed miniature cone was equipped with a four degree-of-freedom in-flight robot. A series of cone penetration tests was performed under four centrifuge acceleration levels. As results, the cone resistances measured at the same confining stress within shallow penetration depth were affected by the centrifugal accelerations. The critical depth was proportional to the cone diameter and relative density. Cone resistances results below the critical depth and soil parameters obtained from the laboratory tests were compared with those by previously proposed empirical relations.

다중흐름모형을 활용한 산림일자리정책 변화과정 분석

김명관 ( Myeong Gwan Kim ),김주미 ( Ju Mi Kim ),오도교 ( Do Kyo Oh ),태유리 ( Yoolee Tae ),장주연 ( Chuyoun Chang ),김재현 ( Jae Hyun Kim ) 한국산림경제학회 2022 산림경제연구 Vol.29 No.2

산림일자리는 노동집약적 특성과 함께 서비스 산업 등 다양한 형태의 일자리가 창출될 수 있는 잠재력이 큰 분야이다. 본 연구는 일자리 문제가 이슈화된 외환위기 시대의 김대중 정부에서 문재인 정부에 이르기까지 산림일자리정책이 역사적으로 어떠한 변동과정을 거쳐 산출되었는지, 시대적 상황에서 어떠한 역할과 성과를 창출해 냈는지를 Kingdon의 다중흐름모형을 활용하여 분석하였다. 그 결과, 첫째, IMF 외환위기, 경제위기, 코로나19 팬데믹이 정책결정자로 하여금 일자리문제를 해결해야 할 문제로 인식하게 한 주요 요인이 되었다. 둘째, 정책혁신가로서 역할을 한 주체는 산림청과 시민사회, 학계가 각 정권별로 주도를 달리했다. 셋째, 산출된 정책은 시대적 변화에 따라 정책혁신가의 개입으로 다시 보완, 개선되어 한단계 상향된 버전의 정책으로 재산출 되었다. 그 결과 정책의 창이 열렸고 산림복지, 휴양, 교육 등의 산림복지서비스 일자리가 확대되었고, 산림분야 사회적경제 활성화를 통해 지역과 연계된 새로운 일자리가 창출되었다. 결론적으로 산림정책이 산촌과 지역의 문제를 해결하고 이를 통해 지역의 활력을 도모하며, 실질적인 도움을 주기 위해서는 시민사회와 파트너십을 통한 사회적 가치를 추구하는 산림일자리정책이 운영되어야 한다. 이상의 내용을 바탕으로 향후 산림일자리정책의 효율성과 성과를 높이기 위한 정책 제언을 하였다. Forest job is a field with great potential to create various types of jobs, such as service industries, along with labor-intensive characteristics. This study analyzed how Korean forest job policy has been changed historicaly and edtablished, and what kind of roles and achievements have been created from the Kim Dae-jung administration when foreign exchange crisis and the job issue occurred, to the Moon Jae-in administration using Kingdon’s Multiple Streams Framework. The study results are as follows. First, the IMF foreign exchange crisis, the economic crisis, and the COVID-19 pandemic became a major factor that made policy makers recognize the job issue as a problem to be solved. Second, the Korea Forest Service, civil society, and academia which played as role as policy innovators was different byeach government. Third, the established policy was supplemented and improved again with the intervention of a policy innovator according to the changes of the times, and it was re-produced as an upgraded version of the policy. As a result, a window of policy was opened, and jobs in forest welfare services such as forest recreation, and education were expanded, and new jobs linked to the region were created through the revitalization of the social economy in the forest sector. In conclusion, in order for forest polices to solve problems in mountain villages and regions, promote regional vitality, and provide practical help, forest job policies which pursue social values through partnerships with civic groups should be operated. Based on the above, policy recommendations were made to improve the efficiency and performance of future forest job policies.

지적장애의 침 치료에 대한 최신 임상연구 동향 - 중국 무작위 배정 임상연구를 중심으로 -

김재현,박용석,이지홍,장규태,Kim, Jae Hyun,Park, Yong Seok,Lee, Jihong,Chang, Gyu Tae 대한한방소아과학회 2021 대한한방소아과학회지 Vol.35 No.4

Objectives The purpose of this study is to analyze the trend of recent randomized controlled trials (RCTs) which used acupuncture for the treatment of intellectual disability in China, and to evaluate the efficacy of the treatment. Methods The RCTs published from January 2017 to July 2021 were searched using China National Knowledge Infrastructure (CNKI). Then, those were analyzed by acupuncture treatment methods used and their results. Results A total of 18 randomized controlled trials were selected and analyzed. Most studies showed significantly higher Intelligence Quotient, Development Quotient, and a total effective rate in an acupuncture treatment group than those of the control group. The most used acupoints were EX-HN1 followed by Niesanzhen, Naosanzhen, Zhisanzhen, Shouzhizhen, GV20. Conclusions Based on the results of the analyzed randomized controlled trials, an acupuncture treatment has shown to be effective in the treatment of intellectual disability. However, additional well designed clinical trials are needed to solidify these findings.

어깨 안정화운동과 복부 안정화 운동에 의한 전방머리자세 성인의 머리척추각도와 어깨뼈 정렬 변화

김재현,이민형,Kim, Jae-Hyun,Rhee, Min-Hyung 대한고유수용성신경근촉진법학회 2021 PNF and Movement Vol.19 No.2

Purpose: This study aimed to adjust the craniovertebral angle and shoulder alignment through shoulder and abdominal stabilization exercises in adults with a forward head posture. Methods: The study participants were 29 adults with a forward head posture, and they were randomly divided into the following groups: 14 participants in a combined exercise group that used shoulder and abdominal stabilization exercises and 15 participants in a shoulder exercise group that used just shoulder stabilization exercises. The participants performed the stabilization exercises for 30 minutes per day, three times a week for five weeks. Results: There were significant differences in the craniovertebral angle after intervention in the shoulder stabilization exercise group (p < 0.05). There were significant differences in the craniovertebral angle and location of the right root of the spine and both inferior angles before and after intervention in the shoulder and abdominal stabilization exercise group (p < 0.05). There was a significant difference in the location of the right root of the spine and the left inferior angle between the groups at the post-test (p < 0.05), and there was a larger change in the shoulder and abdominal stabilization exercise group. Conclusion: There was a significant difference in the craniovertebral angle and a partially significant difference in shoulder alignment before and after intervention in both groups.

가속 Uzawa 방법을 이용한 유도전하계산법

김재현,조광현,하윤도,Kim, Jae-Hyun,Jo, Gwanghyun,Ha, Youn Doh 한국전산구조공학회 2021 한국전산구조공학회논문집 Vol.34 No.4

분자동역학에서의 원자들의 유도전하를 계산하기 위해서는 유도전하를 미지수로 하는 선형방정식을 풀어야 하는데 원자들의 위치가 변화할 때마다 필요한 계산이므로 상당한 계산비용이 요구된다. 따라서 효율적인 유도전하 계산 방법은 다양한 시스템을 해석하기 위해서 필수적이다. 본 연구에서는 constraints가 존재하는 Lagrange 방정식의 해에 대한 선형 시스템, 즉 saddle point를 가지는 문제를 해결하기 위해서 Uzawa method를 도입하였다. Uzawa 매개변수가 수렴 속도에 영향을 미치는 단점을 극복하고 행렬 연산의 효율성을 위해서 Schur complement와 preconditioned conjugate gradient (PCG) 방법을 통해 계산의 효율성을 극대화하는 가속 Uzawa algorithm을 적용한다. 두 금속 나노입자가 전기장에 놓여진 분자동역학 수치모델을 통해서 제시된 방법이 유도전하계산의 수렴성, 효율성 측면에서 모두 향상된 결과를 도출함을 확인하였다. 특히 기존의 가우스 소거법에 의한 계산보다 약 1/10으로 계산비용이 절감되었고, 기본 Uzawa method에 비하여 conjugate gradient (CG)의 높은 수렴성이 입증되었다. To calculate the induced charge of atoms in molecular dynamics, linear equations for the induced charges need to be solved. As induced charges are determined at each time step, the process involves considerable computational costs. Hence, an efficient method for calculating the induced charge distribution is required when analyzing large systems. This paper introduces the Uzawa method for solving saddle point problems, which occur in linear systems, for the solution of the Lagrange equation with constraints. We apply the accelerated Uzawa algorithm, which reduces computational costs noticeably using the Schur complement and preconditioned conjugate gradient methods, in order to overcome the drawback of the Uzawa parameter, which affects the convergence speed, and increase the efficiency of the matrix operation. Numerical models of molecular dynamics in which two gold nanoparticles are placed under external electric fields reveal that the proposed method provides improved results in terms of both convergence and efficiency. The computational cost was reduced by approximately 1/10 compared to that for the Gaussian elimination method, and fast convergence of the conjugate gradient, as compared to the basic Uzawa method, was verified.

무선 센서 네트워크에서 쥐치 정보의 시간차를 이용한 에너지 효율적인 라우팅 프로토콜

김재현,심인보,김홍,이재용,Kim, Jae-Hyun,Sim, In-Bo,Kim, Hong,Lee, Jai-Yong 한국통신학회 2007 韓國通信學會論文誌 Vol.32 No.5B

본 논문에서는 무선 센서 네트워크를 위한 위치 정보의 시간차를 이용한 라우팅 프로토콜(Geo-Back)을 제안한다. Geo-Back은 기존의 위치 기반 라우팅 알고리즘과 달리 주기적인 이웃 노드들의 위치 정보 혹은 하나의 홉 내에 있는 이웃 노드들 수의 정보를 이용하지 않고, 오직 소스와 목적지 노드의 위치 정보만을 이용하며, 최적의 back-off 시간 메커니즘을 사용하여 패킷 전송을 결정한다. 빈번한 토폴로지 변화 환경 하에서, 제안하는 Geo-Back 프로토콜은 업데이트를 위한 브로드캐스트 알고리즘을 사용하지 알고 빠르게 목적지까지 전송하기 위한 최적의 다음 홉을 찾을 수 있으며, 분석 결과 밀집 환경의 무선 센서 네트워크에서 확장성과 향상된 성능을 확인 하였다. In this paper, we propose Geographical Back-off Routing (Geo-Back Routing) protocol for wireless sensor networks. Geo-Back uses the positions of nodes, a packet's destination and a optimal back-off time to make the packet forwarding decisions using only source and destination's location information without information about neighbor nodes' location or the number of one hop neighbor nodes. Under the frequent topology changes in WSNs, the proposed protocol can find optimal next hop location quickly without broadcast algorithm for update. In our analysis, Geo-Back's scalability and better performance is demonstrated on densely deployed wireless sensor networks.

마이크로웨이브 수신기용 광대역 RF 증폭기 설계 및 제작

김재현,윤인섭,고민호,박효달,Kim, Jae-Hyun,Yoon, In-Seop,Go, Min-Ho,Park, Hyo-Dal 한국전자통신학회 2015 한국전자통신학회 논문지 Vol.10 No.6

본 논문은 마이크로웨이브 수신기 구성을 위한 광대역 RF 증폭기를 설계 및 제작하였다. 제안한 광대역 RF 증폭기는 수신된 신호의 안정적인 증폭을 위하여 소스단자에 연결되는 비아까지 EM설계를 하였으며, 능동소자의 소오스(Source) 측이 이상적인 접지(GND)로 동작함에 따라 발진하는 요소를 최소화 하여 광대역에서 일정한 이득 특성 및 안정적인 증폭특성을 얻도록 하였다. 상용 GaAs FET를 사용하고, 광대역 마이크로웨이브 수신기의 IF 주파수 대역인 720 MHz, 4,595 MHz와 6,035 MHz에서 동작하도록 입력 및 출력 정합회로를 구성하였다. 제작 및 측정결과 500 MHz ~ 7 GHz의 광대역 특성을 나타내었으며, 전압이득은 737.5 MHz에서 6.0575 GHz까지 10.635 dB ~ 13.129 dB, 기본파와 제2차 고조파 사이에서 20 dBc 이상의 고조파 억압특성을 나타내었다. In this paper, We proposed a broadband RF amplifier for Microwave band receiver. We also proposed a broadband RF amplifier, designed by using EM simulation for reliable amplification of the received signal. Connected to a source terminal to via, it minimizes those which are the active elements of source-side oscillation as the operating element in an ideal GND, and a constant gain characteristic in a broadband. The goal of this was to obtain stable amplification characteristics. For implementing this architecture, we designed the broadband(500 MHz ~ 7 GHz) RF amplifier by using commercial GaAs FET, which operate on 720 MHz, 4,595 MHz, and 6,035 MHz by impedance matching. The voltage gain is 10.635 dB ~ 14.407 dB(737.5 MHz ~ 6.0575 GHz), P1dB is 20 dBc of band(1st harmonic/2nd harmonic).