• 한국물환경학회지
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• 제24권1호
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• pp.69-77
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• 2008

This study was conducted to know the characteristics of agricultural non-point source pollutants runoff by rainfall events at the upper catchment of Goseong reservoir in Gonjy city, Chungnam Province. For this study, the monitoring sites of the research catchment were set nineteen during the research period (between June 2005 and October 2006). Average runoff coefficient were observed 0.51 in 2005, 0.71 in 2006, respectively. The correlation coefficient (r) between the rainfall and peak-flow was investigated 0.787. By rainfall events, the water quality of the sites were shown like this : BOD 0.555~9.60 mg/L, T-N 0.01~13.50 mg/L, T-P 0.002~2.952 mg/L, and SS N.D~820.0 mg/L. The strong rainfall intensity was the most important factor of the soil erosion. The gabs of the arithmetic mean concentrations and the flow weighted mean concentrations were observed as the followings : BOD 0.0~29.2%, T-N 0.1~11.4%, T-P 0.4~95.2%, and SS 1.7~57.0% in 2005, and BOD 1.0~11.9%, T-N 0.7~7.3%, T-P 9.9~36.5%, and SS 6.6~36.5% in 2006, respectively. The BOD pollution load was 2,117 kg (36% of the total BOD loading of survey periods) while, T-N was 3,209.0 kg (27.9% of the total T-N loading of survey periods), T-P was 136.4 kg (37.4% of the total T-P loading of survey periods) and SS was 72,733.8 kg (51.8% of the total SS loading of survey periods) in the year 2005. In case of 2006, BOD load was 1,321.7, T-N was 2,845.8, T-P was 42.9, and SS was 16,275.8 kg, respectively.

• 한국식품조리과학회지
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• 제21권3호
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• pp.326-338
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• 2005

The purpose of this study was to investigate the effect of isolate soybean protein (ISP) and rice flour on the characteristics of rice noodles. As the levels of ISP and rice flour increased, water binding capacity, swelling power of rice noodle increased. In RVA, pasting temperature, Set back showed an increasing tendency with peak viscosity, holding viscosity, break down, final viscosity of rice noodle increased as the level of rice flour by decreasing. Peak time was not significant. The weight, water absorption and volume of the cooked noodles were decreased. The turbidity of rice noodle increased. The Hunter color L, a-values of the dried rice noodle decreased. Cooked rice noodle quality increased with by decreasing the level of rice flour level. B-values of dried rice noodle and cooked rice noodle increased. Texture profile analysis of cooked rice noodle showed an increase of hardness. Adhesiveness, cohesiveness of cooked rice noodles decreased with by decreasing the level of ISP and rice flour. Gumminess, springiness, chewiness were increased. Sensory evaluation, showed gloss was increased. Hardness and chewiness of the cooked ice noodles were increased. Adhesiveness was not significant. Color and overall- acceptability were increased. Relationship between sensory and mechanical examinations (The overall quality of sensory examination for gloss) had a negative correlation with the mechanical examination for b-value (p.0.05). Mechanical examination for b-value had a positive correlation of sensory evaluation for hardness, chewiness, which had negative correlation of sensory evaluation for color. Scanning Electron, Microscopes observation of rice noodle was showed that the size of the hole grown was increased with by increasing the level of rice flour. From the above results, the most advisable mixture ratio of rice noodle evaluation was can be derived as follows: 171g rice flour, 114g wheat flour, 15g soybean protein isolate, 120ml water, and 6g salt.

• 대한의용생체공학회:의공학회지
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• 제18권1호
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• pp.25-36
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• 1997

To regulate cardiac output of the Total Artificial Heart(TAH) physiologically, the hemodynamic information must be toed back to the controller. So far, our group has developed an automatic cardiac output control algorithm using the motor current waveform, It is, however difficult to detect the preload level such as a filling status of ventricular inflow and the variation of atrial pressures within normal physiologic range(0-15 mmHg) by analyzing the motor current which simultaneously reflects the afterload effect. On the other hin4 the interventricular volume pressure(IVP) which is not influenced by arterload but by preload is a good information source for the estimation of preload states. In order to find the relationship between preload and IVP waveform, we set up the artificial heart system on the Donovan type mock circulatory system and measured the IVP waveform, right and left atrial pressures, inflow and outflow waveforms and the signals represented the information of moving actuator's position. We shows the feasibility of estimating the hemodynamic changes of inflow by using IVP waveform. fife found that the negative peak value of IVP waveform is linearly related to atrial pressures. And we also found that we could use the time to reach the negative peak in IVP waveform, the time to open outflow valve, the area enclosed IVP waveform as unfu parameters to estimate blood filling volume of diastole ventricle. The suggested method has advantages of avoiding thrombogenesis, bacterial niche formation and increasing longterm reliability of sensor by avoiding direct contact to blood.

• 대한전자공학회논문지SP
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• 제46권4호
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• pp.34-41
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• 2009

본 논문에서는 IBCA(Intermediate Boundary Cellular Automata)에 기반을 둔 여원 MLCA(Maximum Length Cellular Automata)와 2D CAT(Cellular Automata Transform)를 단계적으로 이용하여 영상을 암호화하는 방법을 제안한다. 암호화 방법은 먼저, 여원 MLCA를 이용하여 원 영상의 크기만큼 PN(pseudo noise) 수열을 생성한다. 그리고, 원 영상과 생성된 수열을 XOR 연산하여 여원 MLCA 영상으로 변환한다. 그 후, 게이트웨이 값을 설정하여 2D CAT 기저함수를 생성한다. 생성된 기저 함수를 변환된 여원 MLCA 영상에 곱하여 암호화를 한다. 마지막으로 PSNR(Peak Signal to Noise Ratio) 및 안정성 분석을 통하여 제안한 방법이 높은 암호화 수준의 성질을 가졌음을 검증한다.

• Journal of Radiation Protection and Research
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• 제41권3호
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• pp.222-228
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• 2016

Background: We are developing a small size dosimeter for dose estimation in particle therapies. The developed dosimeter is an optical fiber based dosimeter mounting an radiation induced luminescence material, such as an OSL or a scintillator, at a tip. These materials generally suffer from the quenching effect under high LET particle irradiation. Materials and Methods: We fabricated two types of the small size dosimeters. They used an OSL material Eu:BaFBr and a BGO scintillator. Carbon ions were irradiated into the fabricated dosimeters at Heavy Ion Medical Accelerator in Chiba (HIMAC). The small size dosimeters were set behind the water equivalent acrylic phantom. Bragg peak was observed by changing the phantom thickness. An ion chamber was also placed near the small size dosimeters as a reference. Results and Discussion: Eu:BaFBr and BGO dosimeters showed a Bragg peak at the same thickness as the ion chamber. Under high LET particle irradiation, the response of the luminescence-based small size dosimeters deteriorated compared with that of the ion chamber due to the quenching effect. We confirmed the luminescence efficiency of Eu:BaFBr and BGO decrease with the LET. The reduction coefficient of luminescence efficiency was different between the BGO and the Eu:BaFBr. The LET can be determined from the luminescence ratio between Eu:BaFBr and BGO, and the dosimeter response can be corrected. Conclusion: We evaluated the LET dependence of the luminescence efficiency of the BGO and Eu:BaFBr as the quenching effect. We propose and discuss the correction of the quenching effect using the signal intensity ratio of the both materials. Although the correction precision is not sufficient, feasibility of the proposed correction method is proved through basic experiments.

• 한국공간구조학회논문집
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• 제18권3호
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• pp.37-44
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• 2018

A base isolation system is widely used to reduce seismic responses of low-rise buildings. This system cannot be effectively applied to high-rise buildings because the initial stiffness of the high-rise building with the base isolation system maintains almost the same as the building without the base isolation system to set the yield shear force of the base isolation system larger than the design wind load. To solve this problem, the mid-story isolation system was proposed and applied to many buildings. The mid-story isolation system has two major objectives; first to reduce peak story drift and second to reduce peak drift of the isolation story. Usually, these two objectives are in conflict. In this study, a hybrid mid-story isolation system for a tall building is proposed. A MR (magnetorheological) damper was used to develop the hybrid mid-story isolation system. An existing building with mid-story isolation system, that is "Shiodome Sumitomo Building" a high rise building having a large atrium in the lower levels, was used for control performance evaluation of the hybrid mid-story isolation system. Fuzzy logic controller and genetic algorithm were used to develop the control algorithm for the hybrid mid-story isolation system. It can be seen from analytical results that the hybrid mid-story isolation system can provide better control performance than the ordinary mid-story isolation system and the design process developed in this study is useful for preliminary design of the hybrid mid-story isolation system for a tall building.

• 전기전자학회논문지
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• 제24권1호
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• pp.120-126
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• 2020

본 연구에서는 인체의 임펄스 응답 신호를 이용하여 사용자를 인식하는 방법을 제안한다. 인체는 물, 근육, 지방, 뼈 등으로 구성되어 있고, 이러한 구성비는 사람마다 다르게 형성되어 있다. 기존의 인체 통신 연구에서는 인체가 커패시터와 저항으로 이루어진 회로로 모델링 되었고, 회로의 특징은 인체의 구성 특성에 따라 다르다는 것이 밝혀졌다. 따라서 인체는 개인별 고유한 채널로 인식될 수 있고, 이를 이용한 사용자 인식이 가능하다는 연구가 보고 되었다. 이 연구에서는, 임펄스 신호를 인체에 인가하여 임펄스 응답 신호를 측정하고, empirical mode decomposition 기법으로 노이즈를 제거한다. 그리고 10개의 피크 값을 추출하고 피크 간 값의 차이를 특징량으로 사용하여 사용자 인증을 수행하였다. 6명의 참가자로부터 수집한 데이터를 k-nearest neighbors(KNN) 알고리즘을 사용하여 분류 성능을 확인한 결과, 임펄스 응답 신호의 전체 시계열 데이터의 분류 정확도는 91.57%이었으나, 제안한 피크 간 값의 차이를 특징량으로 하여 분류를 하였을 때 분류 정확도가 97.71%로 크게 향상되는 것을 확인할 수 있었다.

• 한국정보통신학회논문지
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• 제20권10호
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• pp.1955-1960
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• 2016

현재, 디지털 시대의 급속 발전과 함께 멀티미디어 관련 영상 장치들이 대중화 되고 있다. 그러나 영상 데이터는 전송하는 과정에서 여러 원인으로 열화가 발생하며 주로 salt and pepper 잡음이 대표적이다. salt and pepper 잡음을 제거하기 위한 대표적인 방법에는 SWMF, RSIF, MNRF가 있으며 기존의 방법들은 고밀도 salt and pepper 잡음 환경에서 잡음 제거 특성이 다소 미흡하다. 따라서 본 논문에서는 salt and pepper 잡음을 제거하기 위해 잡음 판단 후, 중심화소가 비잡음인 경우 원 화소 그대로 보존하고, 잡음인 경우, 국부 마스크 네 방향으로 세분화하여 비잡음 화소가 가장 많은 방향에 대해 3차 스플라인 보간법을 적용하여 처리하는 알고리즘을 제안하였다. 그리고 객관적 판단을 위해 기존의 방법들과 비교하였으며, 판단의 기준으로 PSNR(peak signal to noise ratio)을 사용하였다.

• 대한인간공학회지
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• 제30권6호
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• pp.689-694
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• 2011

Objective: The aim of this study is to evaluate the fluctuation of signal amplitude during repetitive dynamic contraction based on surface electromyography(EMG). Background: The most previous studies were considered isometric muscle contraction and they were difference to smoothing window length by moving average filter. In practical, the human movement is dynamic state. Dynamic EMG signal which indicated as the nonstationary pattern should be analyzed differently compared with the static EMG signal. Method: Ten male subjects participated in this experiment, and EMG signal was recorded by biceps brachii, anterior/posterior deltoid, and upper/lower trapezius muscles. The subject was performed to repetitive right horizontal lifting task during ten cycles. This study was considered three independent variables(muscle, amplitude processing technique, and smoothing window length) as the within-subject experimental design. This study was estimated muscular activation by means of the linear envelope technique(LE). The dependent variable was set coefficient of variation(CV) of LE for each cycle. Results: The ANOVA results showed that the main and interaction effects between the amplitude processing technique and smoothing window length were significant difference. The CV value of peak LE was higher than mean LE. According to increase the smoothing window length, this study shows that the CV trend of peak LE was decreased. However, the CV of mean LE was analyzed constant fluctuation trend regardless of the smoothing window length. Conclusion: Based on these results, we expected that using the mean LE and 300ms window length increased reproducibility and signal noise ratio during repetitive dynamic muscle contraction. Application: These results can be used to provide fundamental information for repetitive dynamic EMG signal processing.

• 설비공학논문집
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• 제20권12호
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• pp.802-807
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• 2008

A Study on Typical Rates of Water-use for School Facilities has been carried out in this work. Water supply system is given much weight in school facilities. Therefore, it set up a basis efficiency using of water sources to calculate typical rates of water use. The results are summarized as follows; 1) On the whole, typical rates of water-use was founded out 15 L/stu. d in pirmary school, 10 L/stu. d in middle school and 30 L/stu. d in high school smaller than the existing it. It was rate of water-use change as season and Max. Rates of water-use was July. 2) I deem that school hours are 5 hour's in primary school, 7 hour's in middle school and 8 hour's in high school. It the concept of 1 hour that is lesson time 40 minutes and resting time 10 minutes in primary school, lesson time 45 minutes and resting time 10 minutes in middle school and lesson time 50 minutes and resting time 10 minutes in high school. 3) It is desired that we calculate the volume of pump and water tank throughout this concept and the size of water tank should be 1.5 times with taking peak load into consideration by this study on typical rate of water-use. 4) The amount of using water increases in gradually and I consider the life cycle of facilities is more than 10 years. As a result, I can forecast that the size will be insufficiency but I deem that if we devise a plan about parallel pumping on water tank space, we can cope with it. Also, it is expected that we can cut back the transport energy by controlling pump volume.