녹내장 환자에서 레이저 시신경유두 분석기와 광간섭 단층 촬영기의 결과 비교

김준모, 박기호, 김태우, 김동명Joon Mo Kim M.D. Ki Ho Park M.D. Tae Woo Kim M.D. Dong Myung Kim M.D. 대한안과학회 2006 대한안과학회지 Vol.47 No.4

Purpose: To evaluate the ability of Stratus OCT and HRT II with Moorfields′‘analysis to detect localized RNFL defects and to evaluate the accordance of Stratus OCT and HRT II results in glaucoma patients. Methods: A total of 60 patients (119 eyes) who had localized RNFL defects of either eye in red-free fundus photographs unserwent evaluation by Stratus OCT and HRT II. For the results of Stratus OCT and HRT II with Moorfields′analysis, normal distribution percentiles less than 5% were considered a significant RNFL defect. For each disc, superotemporal and inferotemporal portions were evaluated. The diagnostic abilities of Stratus OCT and HRT II to detect localized RNFL defects were calculated. The results of HRT II were compared with those of Stratus OCT. Results: The overall sensitivity, specificity, positive predictive value and negative predictive value to detect localized RNFL defects were 67.9%, 88.9%, 84.3% and 76.5% in Stratus OCT and 67.3%, 64.8%, 62.2% and 69.6% in HRT II, respectively. Compared with Stratus OCT, 67.2% of HRT II results were in accord in the superotemporal portion and 68.9% in the inferotemporal portion. The accordance of detection of RNFL defects between the two instruments in the inferotemoral portion was higher (79.2%) than others. Conclusions: Stratus OCT with a normative database is a useful aid to detect localized RNFL defects in early glaucoma. If observation of topographic changes of the optic disc with HRT II is added, results will be even better.

홍씨 앞방각측정법의 임상적 유용성

강신희, 박기호, 홍철, 김동명Shin Hee Kang M.D. Ki Ho Park M.D. Chul Hong M.D. Dong Myoung Kim M.D. 대한안과학회 2007 대한안과학회지 Vol.48 No.3

Purpose: To compare the Hong`s grading method, utilized for slit-lamp grading of the mid-peripheral angle, with other conventional grading methods. Actual angle was measured by ultrasound biomicroscopy (UBM) for comparison. Methods: Fifteen eyes with narrow angles and eighteen eyes with wide angles were studied. The average age of thirty-three subjects was 46.8±19.2, and the male to female ratio was 1:3.7. The mid-peripheral angle was graded by Hong`s, van Herick`s and Spaeth`s grading system. The actual anterior chamber angle was evaluated by UBM and the correlation between each grading system and actual angle was investigated. Results: The results from the Hong`s grading (r=0.802, R2=0.643, p<0.01), Spaeth`s grading (r=0.728, R2=0.530, p<0.01) and van Herick`s grading (r=0.618, R2=0.382, p<0.01) methods correlated significantly with the actual angles. Conclusions: The Hong`s grading method was an easy and effective tool to evaluate anterior chamber angle. In addition, the results of the Hong`s grading method were closer to the actual angle than the other methods.

HST 중립밸브의 해석모델 개발 및 설계변수 민감도 분석

김동명(D. M. Kim),장주섭(J. S. Jang),김수철(S. C. Kim) 유공압건설기계학회 2014 드라이브·컨트롤 Vol.11 No.3

The neutral valve for controlling the HST is one of the important valves for the vehicle control. Neutral valve takes a role of blocking or transmitting power to the vehicle. The operating principle of the neutral valve was developed through the analysis model. We also investigated the logical validity by analyzing the results of the analysis model. The analysis model was developed by using SimulationX witch is commercial software. The number of holes in the piston was selected as a variable initial compression of the spring, and the magnitude of the pressure pulsations and the diameter of the orifice for the sensitivity analysis were performed to design sensitivity analysis of the neutral valve.

부하 감지형 굴삭기 시스템의 특성과 효율 분석

김동명(D. M. Kim),이정민(J. M. Lee),정원지(W. J. Jung),장주섭(J. S. Jang) 유공압건설기계학회 2015 유공압건설기계학회 학술대회논문집 Vol.2015 No.6

In this study, we develop analytical model of an open center system and the load-sensing system and analyze the system characteristics and efficiency. In order to analyze characteristics of the pressure and flow of the main control valve of an open center system, test was performed on a at each port. The authors studied the reliability of the analysis model by confirming the similarity of the analysis results and the test results before analyzing the characteristics of the system. Developing the main control valve of the load sensing type added a flow sharing valve and a notch shape to the open center system on the proven reliability. The authors was performed the simulation under the same load condition in order to compare the efficiency of the systems. Under the same load conditions, The authors was performed the simulation in order to compare the efficiency of the systems. Also, The authors was investigated in the combined operation performance by means of analyzing the characteristics of flow distribution under different load conditions.

갠트리 해양크레인의 해석모델 개발

김동명(D. M. Kim),이수용(S. Y. Lee),장주섭(J. S. Jang) 유공압건설기계학회 2013 유공압건설기계학회 학술대회논문집 Vol.2013 No.6

In this study, we try to develop hydraulic crane analysis model. The subject crane is gantry crane. Before producting system, we will simulate hydraulic circuit. In this way, it is considered to help us predict design specification validity and problem. The step of developing interpretation model is as in the following. The hydraulic parts are developed as unit model on the basis of catalogue. And sub circuit is constructed by extending unit model. We check the logic validity of sub circuit by analysing output from interpret model. It is considered to be basis of developing the whole crane models.

내부 파일럿 작동식 유량 제어밸브의 성능에 관한 연구

김동명(D. M. Kim),장주섭(J. S. Jang),김태인(T. I. Kim),이종찬(J. C. Lee),유충목(C. M. Yoo),한성민(S. M. Han),남용윤(Y. Y. Nam),서자호(J. H. Seo),박진선(J. S. Park) 유공압건설기계학회 2016 유공압건설기계학회 학술대회논문집 Vol.2016 No.6

Recently, an electronic hydraulic valves on behalf of the main control valve is widely used. The electric hydraulic valve is one of the main control valve to control the various actuators in the hydraulic system(This valve was a cartridge type of a 2port/2way and EHPV(Electro hydraulic proportional valve) and the main poppet is composed of a single valve. A main poppet in the electric hydraulic valve is determine to main flow line, which includes the ability to restrict or permit the reverse. Supply flow is proportionally controlled by the inner pilot pressure and the pilot pressure is controlled by the current of input EHPV. In general, pilot operated valves are supplied to the control pressure from the outside. However, this valve is supplied with pilot pressure from the inside. Therefore, the design variables of the main valve poppet and EHPV are closely related to each other. It was carefully analyzed the valve structure and how it works to improve the performance of the valve. We developed an analytical model considering the geometric shape and spring stiffness. The test results and the analysis confirmed the accuracy of the analysis model by comparing the results, and the performance enhancement study was performed using the analysis model. We examined the characteristics of the control range and the power loss by using the analysis model.

21톤급 전기 굴삭기용 파일럿 작동식 유량제어 밸브의 해석모델 개발 및 검증

김동명(D. M. Kim),남용윤(Y. Y. Nam),서자호(J. H. Seo),장주섭(J. S. Jang) 유공압건설기계학회 2015 드라이브·컨트롤 Vol.12 No.3

An electro hydraulic poppet valve (EHPV) and a variable orifice poppet are assembled in a single block, which is referred to as a RHINO but is also generally called a pilot-operated flow control valve. In this study, we analyzed the structure and the operating principle for a RHINO applied in a 21-ton electric excavator system. The RHINO was experimentally tested to measure the dynamic responses and the pressure energy loss. In this test, we investigated the variation in the conductance coefficient according to the increase in the supply pressure under a constant current and a variation in the flow rate according to the increase in the current. Then, the geometrical shapes and the spring stiffness of the RHINO were considered to develop an analysis model. The characteristics (current-force and hysteresis) for the solenoid based on the experimental data were reflected in the analysis model that was developed, and the reliability of the analysis model was also verified by comparing the experimental and analytical results. The developed model is thus considered to be reliable for use in a wide range of applications, including optimum design, sensitivity analysis, parameter tuning, etc.

메인 컨트롤밸브의 해석모델 개발 및 검증

김동명(D. M. Kim),이정민(J. M. Lee),정원지(W. J. Jung),장주섭(J. S. Jang) 유공압건설기계학회 2015 드라이브·컨트롤 Vol.12 No.2

In order to control the actuators of hydraulic machinery such as excavators, various control valves are typically assembled in a single block. Such a control block is called a main control valve(MCV). In this paper, we analyzed the working principle and the particular purpose of the design of all valves included in the MCV system. To Examine the reliability of the analysis model, the pressure drop of the MCV at each port was measured. The authors developed an analytical model of the control valve(main spool, load poppet, pressure relief, make up, and regeneration). The authors considered the notch shape of the spool while developing the analytical models of the main spool valve. Most importantly, at the stage before the analysis model was applied in the design tuning, the reliability was ensured by comparing the analysis results with the test results. This paper showed a process of developing an analysis model that can be utilized in the design and tuning stages.

기능성 나노식품의 제조기술 및 전망

김동명 ( D. M. Kim ),곽해수 ( H. S. Kwak ) 한국낙농식품응용생물학회 2005 Journal of Dairy Science and Biotechnology (JMSB) Vol.23 No.1

가교밀도에 따른 자기가교형 우레탄/아크릴 하이브리드의 물성에 관한 연구

김동명 ( D. M. Kim ),최희성 ( H. S. Choi ),노시태 ( S. T. Noh ) 한국공업화학회 2003 응용화학 Vol.7 No.1

Blends of waterborne urethane and acrylic polymer systems were studied to obtain a composite emulsion that would have all of the advantages of the two polymers without their associated disadvantages. An approach to achieve extensive polymer-polymer interactions through crosslinking was studied to optimize the positive aspects of each polymer. The crosslink system used an acrylic polymer emulsion containing ketone groups and a polyurethane dispersion incorporating a hydrazine group. Hydrazine-terminated polyurethane dispersions(PUDs) were synthesized from carbonate type polyol(PCD), ionic chain extender(DMPA), diisocyanate(IPDI), agent for end-capping(ADH). Self-crosslinking type PU/PA hybrids were prepared with free radical polymerization of MMA, 2-EHA, DAAM to introduction ketone group in acryl monomer-swelled PUDs. Crosslinking reaction was determinated by FT-IR. Partical size and gel contents of PUDs and PU/PA hybrids film were investigated. By T-IR, it was observed that the formation of imino bonds between ketone groups and hydrazide groups.