능동 소나에서 시간적으로 긴 펄스에 대한 정합 필터의 효율적인 분할 기법

신동훈,김진석,Shin, Donghoon,Kim, Jin Seok 한국음향학회 2014 韓國音響學會誌 Vol.33 No.4

최근 능동소나에서 표적의 탐지성능을 향상하기 위해 상당히 긴 펄스가 사용되고 있다. 이렇게 송신 파형의 길이가 길어지면 콘볼루션(convolution)을 이용하여 구현한 정합필터는 과도한 연산량이 요구되어 구현측면에서 불리하다. 주파수 영역에서 중첩-합(overlap-add) 또는 중첩-저장(overlap-save) 방법을 이용한 정합필터를 수행하면 이러한 문제를 해결할 수 있으나, 실시간 처리를 위해 시스템의 입출력 연동주기가 고정된 경우 FFT 길이가 제한되어 성능저하가 발생한다. 이 경우 연산효율을 높이기 위한 방법으로 필터를 균등 분할하되 IFFT 연산의 재사용을 통해 연산 효율을 높이는 FDL(Frequency Delay Line, 주파수 영역 지연-합) 방법과 필터를 가변적으로 최적 분할하는 MC(Minimum Cost, 최소 비용) 방법이 알려져 있다. 본 논문은 위 두 가지 방법을 결합하여, 정합필터를 효율적으로 분할하여 수행할 수 있는 새로운 방법을 제안하였다. Recently, long pulses are transmitted for target detection in active sonar application. Matched filtering implemented by simple convolution algorithm, requires massive computational power for long replica. The computational loads are reduced significantly by implementing the convolution in the frequency domain with overlap add method, but the performance degrades for specified input/output system delay which constrains the size of FFT function. For performance improvement, the replica could be partitioned into uniform blocks (FDL) by re-using IFFT operations, or variable blocks of increasing length (MC) by using the largest possible blocks to calculate the convolution. In this paper, by combining the strong points of the two methods, we propose a new filter partition structure that allows for further optimization of the previous two methods.

고온환경에서의 한국인 작업능력 - 고추가 피부의 온도 및 전기저항에 미치는 영향 -

신동훈,조장제,장세구,고재평,엄륭의,Shin, Dong-Hoon,Cho, Jang-Ze,Chang, Se-Koo,Koh, Jae-Pyong,Earm, Yung-E 대한생리학회 1970 대한생리학회지 Vol.4 No.1

In order to investigate the changes in the temperature regulation mechanism following ingestion of red pepper, twenty healthy man were given 2 gms of powdered red pepper each in 100 ml of water at room temperature, $20^{\circ}C$, Simultaneous recordings of temperature and electrical resistance of the skin of forehead were taken by means of Physiograph, using appropriate transducers. Temperature of various spots such as the cheek, upper tack and the forearm was also measured by the telethermometer at interval of two minutes. The results obtained were as follows: 1. Seventeen out of 20 subjects showed immediate rise in the skin temperature of the forehead, and 11 of them manifested the oscillating pattern of the skin temperature. The average of the largest peak amplitude was $0.58{\pm}0.355^{\circ}C$. 2. Even those who failed to show the immediate rise in the temperature did not keep the quiescence over 9 minutes, and delayed responses were revealed. 3. The rise in tile skin temperature is the favourable sign for the heat discipating mechanism only because the sweat glands are activated with the concomittant rise in the temperature of the skin. 4. There was a preceding or coincide fall in the electrical resistance of the skin, and it was also attributed to the glandular activity. 5. At rather cool room temperature, $20^{\circ}C$, no visible sweat was seen during the period of observation. Nevertheless it was obvious that latent activation of the sweat glands was triggered and the. threshold was lowered. This situation imitates the acclimatized condition in the hot environment, and it is likely to increase the tolerance in tropical climate from the view point of temperature regulation.

ZCB00 인공수정체의 부분결합간섭계와 초음파 방식의 술 후 굴절 예측치 차이

신동훈,임동희,유자영,정의상,정태영,Dong Hoon Shin,Dong Hui Lim,Ja Young You,Eui Sang Chung,Tae Young Chung 대한안과학회 2014 대한안과학회지 Vol.55 No.4

Purpose: To evaluation the accuracy of the IOL power calculation formulae measured by IOL Master<sup>® and applanation ultrasonography for the Tecnis ZCB00 IOL Methods: We performed a retrospective study of 170 eyes in 121 patients who underwent cataract surgery in our hospital with AMO Tecnis ZCB00 IOL.s. The SRK/T formula was used to predict the patient's implanted IOL power. Differences in the predicted refractive errors between IOL Master<sup>® and ultrasonography were analyzed and factors attributed to the differences were also analyzed. Three months after cataract surgery, mean numeric error and mean absolute error were analyzed. Results: SRK/II and SRK/T formulas calculated using ultrasonography showed differences compared to the same formulas calculated using IOL Master<sup>®, in which hyperopic shift was also demonstrated. No definite factor was attributed to the differences between the 2 methods. Although the 3 formulas of IOL Master<sup>® showed no significant difference in refractive errors, the SRK/T formula calculated using IOL Master<sup>® showed the least mean absolute and numeric errors. Conclusions: IOL Master<sup>® is considered more suitable when determining proper AMO Tecnis ZCB00 IOL power in cataract surgery. The hyperopic shift should be considered when calculating the IOL power using only ultrasonography. J Korean Ophthalmol Soc 2014;55(4):527-533

Estimating Sea Surface Temperature Change after Tide Embankment Construction using Landsat Data

신동훈,이규석,Shin, Dong-Hoon,Lee, Kyoo-Seock The Korean Association of Geographic Information S 2006 한국지리정보학회지 Vol.9 No.4

본 연구는 Landsat Thematic Mapper (TM) 영상의 열적외선 (Thermal Infrared: TIR) 밴드 자료를 이용하여 시화호와 그 주변지역의 해수면 온도 (SST: sea surface temperature)를 검출하고, 시화방조제 공사 후의 토지피복변화를 파악하기 위해 수행되었다. 해수면 온도의 측정은 해양체계 뿐만 아니라 해양과 대기 사이의 열적인 경계범위 연구에 있어 중요하다. 1970년대 이후, AVHRR (advanced very high resolution radiometer)과 Landsat TM (Thematic Mapper)과 같은 인공위성 영상의 원격탐사기법을 이용한 해수면 온도의 추출이 이루어졌다. 그러나 AVHRR 영상은 우리나라의 서해안 지역과 같은 매우 복잡한 해안선을 가지고 있는 지역에서는 조악한 공간 해상도로 인해 해수표면온도 추출에 한계가 있다. Landsat TM 위성영상은 본 연구지역과 같이 복잡하고 좁은 해안지역의 해수면 온도 추출에 유용하게 사용된다고 판단된다. This study investigates to detect Sea Surface Temperature (SST) and land cover change after tide embankment construction using Landsat Thematic Mapper (TM) Thermal Infrared (TIR) band data at Shihwa Lake and surrounding area. SST measurement is important for studies of both the structure of the ocean and as the thermal boundary between the ocean and the atmosphere. Since 1970s, the derivation of SST by satellite remote sensing (RS) has been applied to earth surface using Advanced Very High Resolution Radiometer (AVHRR) and Landsat TM. However, AVHRR has restriction in deriving SST in the area whose shoreline is complicated like western coast in South Korea because of coarse spatial resolution. The TIR band of TM images can be used to detect SST change whose shoreline is complicated and narrow like the study site. Thus, multi-temporal TM images were used for SST change detection in this study.

평면공간에서 다중 센서간 도달 시간차를 이용한 해석적인 최소제곱오차 음원 위치 추정 방법

신동훈,Shin, Dong-Hoon 한국군사과학기술학회 2011 한국군사과학기술학회지 Vol.14 No.4

A closed-form technique is presented for estimating a single source location from a set of noisy time delay measurements between distributed sensors. The localization formula is derived from nonlinear least squares minimization over the unknowns of target range and bearing in polar coordinates. Computer simulation results are provided for the purpose of performance analysis. Constrained least squares minimization method with prior source location information is also discussed.

방사성 옥소 치료 및 전신스캔 전 처치 시의 갑상선 자극호르몬 농도에 따른 갑상선글로불린의 변화

신동훈,강윤중,박주승,조병선,김창남,이민구,최영진,Dong Hun Shin,Yoon Jung Kang,Joo Seung Park,Byung Sun Joe,Chang Nam Kim,Min Koo Lee and Young Jin Choi 대한갑상선-내분비외과학회 2012 The Koreran journal of Endocrine Surgery Vol.12 No.1

영팽창선이론(零膨脹線理論)에 의한 동적토압해석(動的土壓解析)

신동훈,황정규,Shin, Dong Hoon,Hwang, Jung Kyu 대한토목학회 1993 대한토목학회논문집 Vol.13 No.5

본 연구에서는 토체내에 발생하는 파괴면(破壞面)의 방향(方向)은 선형변형율증분(線形變形率增分)이 0인 영팽창선(零膨脹線)의 방향(方向)과 일치한다고 하는 Roscoe의 영팽창선이론(零膨脹線理論)과 Mononobe-Okabe의 동적(動的) 토압이론(土壓理論)을 응용(應用)하여 지진(地震)의 영향(影響)을 고려한 동적토압이론식(動的土壓理論式)을 제안하였다. 동적토압식을 유도함에 있어서 벽체는 연직이고 재하중(載荷重)이 없으며, 뒷채움면은 수평면이고 그 재료는 조밀한 비점착성(非粘着性) 사질토(砂質土)로서 지진시에도 토질정수(土質定數)는 변화되지 않는 것으로 가정하였으며, 지진에 의한 영향을 고려하기 위하여 수평방향진도(水平方向震度)만을 고려하였다. 한편, 제안된 토압식에 포함되어 있는 수평진도(水平震度), 흙의 내부마찰각(內部摩擦角), 벽마찰각(壁摩擦角) 및 다이레이션각(角)의 영향을 분석하였으며, 유도된 이론식을 Mononobe-Okabe의 토압식과 비교분석하였다. The present study was made based on the zero extension line theory and the well-known Mononobe-Okabe's to determine the dynamic earth pressures acting on the retaining walls. The zero extension line theory, which was proposed by Roscoe et al., assumes the coincidence between the loci of failure and the zero extension lines in soil mass. ln order to compute the dynamic earth pressure developed by an earthquake, it was assumed that for the vertical retaining walls with no surcharge, the backfill materials are dense and cohesionless sandy soils, there are no changes in soil parameters during earthquake, and the horizontal earthquake intensity is considered. The effects of horizontal earthquake intensity, internal friction angle of soil, wall friction angle and dilation angle, on the earth pressure coefficients were analysed. Final1y, the presented theories were successfully compared with the Mononobe-Okabe's as well.

Trichophyton rubrum의 경구용 항진균제에 대한 시험관내 감수성

신동훈,최종수,김기홍 ( Dong Hoon Shin,Jong Soo Choi,Ki Hong Kim ) 대한피부과학회 1990 大韓皮膚科學會誌 Vol.28 No.5

Seismic noise level variation in South Korea

신동훈,Jin Soo Shin,강태섭 한국지질과학협의회 2009 Geosciences Journal Vol.13 No.2

Variations of seismic background noise in South Korea have been investigated using power spectral analysis. We have estimated the power spectral density of seismic noise for 30 broadband stations from 2005 to 2007. In the frequency range 1–5 Hz, diurnal variations of noise level and daily differences in daytime noise level are observed at most stations, suggesting that cultural activities contribute to the noise level of a station. The variation in the number of stations detecting an event, however, suggests that cultural noise has little influence on the detection capability of events over magnitude 2.0. In the frequency range 0.1–0.5 Hz, a double-frequency (DF) peak is dominant at all stations. Clear seasonal variations of peaks are observed, while much less shown in the frequency range 1–5 Hz. DF noise levels are higher in winter than in summer. Strong DF peaks occur in summer when Pacific typhoons near the Korean Peninsula. The discrepancy in time between DF peaks at seismic stations and peaks of significant wave height at buoys, as well as the decrease of DF peaks with increased latitude, indicate that the likely source region of DF peaks is located in the Southern Sea of Korea.

가시광선중합화에 따른 충전용 Glass Ionomer Cement의 물리적 성질에 관한 연구

신동훈,권혁춘,Shin, Dong-Hoon,Kwon, Hyuk-Choon 대한치과보존학회 1992 Restorative Dentistry & Endodontics Vol.17 No.2

The aim of this study was to investigate the physical properties of visible light curing Glass Ionomer cement for restorative esthetic filling. The control group was the autopolymerizing GC Fuji II Glass Ionomer cement (2.2: 1 P/L ratio) and the experimental groups were made by following procedure. To induce the polymerization by visible light, the powder of GC Fuji II GI cement and the liquid of Vitrabond for base & liner were mixed in an amalgam capsule with 2.5:1, 3.0:1, 3.5:1 P/L ratio (% wt/wt). After fabrication of specimens, compressive strength, fracture toughness ($K_{IC}$) Scanning Electron Microscope and X-ray Diffraction, water-leachable content, marginal leakage and surface roughness were studied. The results were as follows: 1. Only experimental No. 1 group (visible light curing) showed less compressive strength than control group 1 hour after curing. Strength was increased with aging in all groups, so the compressive strength of light curing groups was no less than that of autopolymerizing group after 3 weeks. 2. Experimental No.3 group (visible light curing) was inferior to No.2 group (visible light curing) in fracture resistance but light curing groups were more resistant to fracture than autopolymerizing group and showed ductile fracture pattern as compared with the brittle fracture pattern of autopolymerizing group. 3. From scanning electron microscopic image, various sized unreacted powder particles, surrounded by silica gel, were embedded in polysalt matrix. Light curing groups showed little crack and more dense unreacted particles than autopolymerizing group. 4. From X-ray diffraction analysis, GC Fuji II Glass Ionomer cement powder and all groups showed glassy appearance but light curing groups seemed to be more intensive in crystaline than autopolymerizing group. S. The most significant dissolution was shown in early setting period in all group. Light curing groups were dissolved less than autopolymerizing group. 6. Marginal leakage was not different significantly in case of cavity margin composed of same tooth structure (ex. only enamel margin, only dentin margin) but much more leakage was shown in dentin/cementum margin than enamel margin. In only case of only enamel margin, light curing groups were superior to autopolymerizing group. 7. All groups showed relatively smooth surface, which irregularity was less than $1{\mu}m$. Light curing groups were smoother than autopolymerizing group.