자전거 에르고미터 운동처방 시스템 개발

신동환,최규정,윤재량,황종학,백진호 한국스포츠정책과학원(구 한국스포츠개발원) 2000 체육과학연구 Vol.11 No.1

본 연구는 자전거 에르고미터를 이용하여 운동을 보다 규칙적이고 목표 지향적으로 운동할 수 있도록 하는 운동처방 시스템을 구현하였다. 1997년에 개발된 자전거 에르고미터(신동환 등, 1997)를 이용했고 퍼스널 컴퓨터와의 데이터 연결은 IC(integrated circuit)카드를 이용했다. IC카드를 이용하여 운동한 기록(운동날짜, 운동시간, 소모 칼로리)을 컴퓨터에 저장하고, 저장된 데이터를 기본으로 운동처방 프로그램(김재호 등, 1994)을 동작시켜 운동처방 데이터를 만들어 낸다. 처방된 데이터를 IC카드에 기록하고 기록된 데이터를 자전거 에르고미터가 읽어와 이것에 의해 운동을 하게 된다. IC 카드를 이용한 운동모드는 크게 두 가지 방법이 있다. 첫번째 방법은 비만인 사람이 체중을 감량하기 위한 체중감량 모드가 있고, 두번째 방법은 체력을 증진시키기 위한 체력증진 모드가 있다. IC카드 운동모드는 모두 심박수를 기준으로 자동부하 방식을 택했으며 체중감량모드는 운동소비 칼로리를, 체력증진모드는 운동시간을 운동목표로 하여, 운동소비 칼로리나 운동시간이 목표치에 도달했을 때 운동을 마치게 했다.

Nephrogenic Adenoma -1증례 보고 및 문헌고찰-

신동환,양우익,김태승,이유복,노용수,양승철,이진무 대한병리학회 1982 Journal of Pathology and Translational Medicine Vol.16 No.4

수종 치주큐렛의 작업측 마모도의 비교연구

신동환,임성빈,정진형,Shin,,Dong-Whan,Lim,,Sung-Bin,Chung,,Chin-Hyung 대한치주과학회 1999 Journal of Periodontal & Implant Science Vol.29 No.3

The purpose of this study was to evaluate the degree of wear of periodontal curet's cutting edges made by three different manufacturers. In the first case of the experiment, this study was done with each new curett in the following three experiment. Twelve new double-ended No. 11/12 Gracy curettes from three different manufacturers (A, B and C) was randomly selected from our stock at first test. They were weared by wear tester with fixed pressure and limited distance. This study measured the width of worn curettes'cutting edge. The results were as follows ; 1)In 50 times experiment, this study discoverd that each manufacturer's curette was appeared with different degree of wear (p<0.01) 2)In 100 times experiment, this study result similarly to the 50 times experiment(p<0.01). 3)In 150 times experiment, the result of this study were alike as the X50 experiment and X100 experiment. In the second case of the experiment, the study was done with a curett of a manufacturer in the following three experiment. Two double-ended No. 11/12 Gracy curette from three different manufactures (A, B and C) was randomly selected from our stock at second test. 1)In 50 times experiment, this study discovered that each manufacturer's curette was appeared with different degree of wear (p<0.05). 2)In 100 times experiment, the result was same, compared with the 50 times experiment. 3)In 150 times experiment, this study also discovered that the result was same with the result of the upper two cases. In conclusion, this study discovered that the two cases of experimental were shown with a same result.

폐의 전암성(前癌性) 병변

신동환 주식회사 녹십자 2003 녹십자의보 Vol.31 No.3

위성 탑재체용 26.4 GHz 국부발진기의 설계 및 제작

신동환,류근관,장동필,이문규,염인복,오승엽 한국통신학회 2006 韓國通信學會論文誌 Vol.31 No.2

Monocrotaline 투여로 인한 백서 폐혈관 변화의 형태학적 및 형태계측학적 연구

申東煥,李有福 연세대학교 의과대학 1987 연세의대논문집 Vol.20 No.2

임프란트 미세나사선이 주위골 수준변화에 미치는 영향에 대한 1년간의 전향적 비교 연구

신동환,조규성,박광호,문익상,Shin,,Dong-Hwan,Cho,,Kyoo-Sung,Park,,Kwang-Ho,Moon,,Ik-Sang 대한치주과학회 2003 Journal of Periodontal & Implant Science Vol.33 No.3

The success of dental implant therapy relies mainly upon the presence and maintenance of bone adjacent to implant. An 1-year prospective study was performed, upon the patients who were diagnosed as having chronic adult periodontitis, and had been treated with dental implant. The purpose of this study was to measure the radiographic bone level changes proximal to Astra Tech Single Tooth Implants (ATST, Astra Tech AB, $M{\"{o}}lndal$, Sweden) with microthread and Astra Tech TiOblast Implant (ATTB) without microthread supporting fixed partial prosthesis. Measurements were used to determine mean marginal bone loss during the first year of loading, 17 subjects with its partial prosthesis supported by 37 implants were followed up for an 1-year period. The marginal bone loss of implants was positively correlated with the retention factor, microthread($Microthread^{TM}$) in crestal area of ATST. The results were as follows. 1. The mean marginal bone loss of ATST was 0.226${\pm}$0.395mm, while ATTB was 0.440${\pm}$0.360mm. There was a statistically significant difference between ATST and ATTB (p<0.05). 2. The mean bone loss of the upper jaw fixtures was 0.269${\pm}$0.265mm for ATST and 0.529${\pm}$0.417mm for ATTB . There was a statistically significant difference between ATST and ATTB (p<0.05). In the lower jaw the corresponding figures were 0.167${\pm}$0.231mm and 0.313${\pm}$0.214mm, respectively. There was no significant difference between ATST and ATTB (p>0.05). 3. The mean bone loss of ATST was lower than that of ATTB at all sites according to bone quality. There was a statistically significant difference between ATST and ATTB at bone quality type III(p <0.05). In conclusion, the mean bone loss of ATST was smaller than that of ATTB . Therefore, the retention factor of crestal area, microthread ($Microthread^{TM}$) was effective to maintenance of marginal bone level around fixture.

6-GHz-to-18-GHz AlGaN/GaN Cascaded Nonuniform Distributed Power Amplifier MMIC Using Load Modulation of Increased Series Gate Capacitance

신동환,염인복,김동욱 한국전자통신연구원 2017 ETRI Journal Vol.39 No.5

A 6-GHz-to-18-GHz monolithic nonuniform distributed power amplifier has been designed using the load modulation of increased series gate capacitance. This amplifier was implemented using a 0.25-lm AlGaN/GaN HEMT process on a SiC substrate. With the proposed load modulation, we enhanced the amplifier's simulated performance by 4.8 dB in output power, and by 13.1% in power-added efficiency (PAE) at the upper limit of the bandwidth, compared with an amplifier with uniform gate coupling capacitors. Under the pulse-mode condition of a 100-ls pulse period and a 10% duty cycle, the fabricated power amplifier showed a saturated output power of 39.5 dBm (9 W) to 40.4 dBm (11 W) with an associated PAE of 17% to 22%, and input/output return losses of more than 10 dB within 6 GHz to 18 GHz.

A Decade-Bandwidth Distributed Power Amplifier MMIC Using 0.25 μm GaN HEMT Technology

신동환,염인복,김동욱 한국전자파학회 2017 Journal of Electromagnetic Engineering and Science Vol.17 No.4

This study presents a 2–20 GHz monolithic distributed power amplifier (DPA) using a 0.25 μm AlGaN/GaN on SiC high electron mobility transistor (HEMT) technology. The gate width of the HEMT was selected after considering the input capacitance of the unit cell that guarantees decade bandwidth. To achieve high output power using small transistors, a 12-stage DPA was designed with a nonuniform drain line impedance to provide optimal output power matching. The maximum operating frequency of the proposed DPA is above 20 GHz, which is higher than those of other DPAs manufactured with the same gate-length process. The measured output power and power-added efficiency of the DPA monolithic microwave integrated circuit (MMIC) are 35.3–38.6 dBm and 11.4%–31%, respectively, for 2–20 GHz.

Analytic Approaches for Keeping High Braking Efficiency and Clamping Efficiency of Electro Wedge Brakes

신동환,이성훈,Choong-Pyo,Jeong,권오석,박태상,진성호,반동훈,양승한 한국정밀공학회 2015 International Journal of Precision Engineering and Vol. No.

The transfer from engine drive vehicles to electric vehicle has been proceeding due to fuel exhaustion, higher fuel costs, and environmental restrictions. This trend has also led to a transition in brake system from the hydraulic brake system to the electric brake system, which uses electric power. This electric brake system has led to an enhancement of safety and eco-friendliness due to a reduction braking distance, a rapid-response property, and the elimination of braking oil. However, one of the big problems to solve for practical usages is the need of a high power motor to enable braking forces as strong as those of hydraulic brake systems. Therefore, it is necessary to develop high efficiency electro mechanical brakes with a proper reinforcement mechanism to solve this problem. In this paper, we describe a wedge structure that has a self-reinforcing effect; we propose a proper actuating direction for a movable wedge to obtain greater clamping efficiency and braking efficiency, which will mean a better relation of the motor force as the input to the braking force as the output. Further, we propose the method to keep the most braking efficiency and clamping efficiency without reference to the variations of frictional coefficient.