• Journal of the Optical Society of Korea
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• 제13권2호
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• pp.251-255
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• 2009

In the non-contact 3-dimensional (3D) shape measurements, the fringe pattern projection method based on the phase-shifting technique has been considered very effective for its high speed and accuracy. The digital fringe projector in particular has great flexibility in generating fringe patterns since the patterns can be controlled easily by the computer program. In this work, we have developed a high-speed digital laser grating projection system using a laser diode and a polygon mirror, and evaluated its performance. It has been demonstrated that all the optical measurements required to find out the profile of a 3D object could be carried out within 31 ms, which confirmed the validity of our 3D measurement system. The result implies the more important fact that the speed in 3D measurement can be enhanced remarkably since, in our novel system, there is no device like a LCD or DMD whose response time limits the measurement speed.

• 음성과학
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• 제8권3호
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• pp.235-241
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• 2001

The purpose of this study was to determine the correlation between HNR and NNE, EGG HNR and EGG NNE, which are most closely related to noise of voice. Dr. Speech was utilized to obtain acoustic measurements and physiologic measurements, simultaneously. In addition, no normative data of HNR, NNE, EGG HNR, EGG NNE are available in Korean subjects at present. The Pearson correlation coefficient was used to find the correlation between HNR and NNE, EGG HNR and EGG NNE. The results of the study were as follows: First, there was no correlation between HNR and NNE. Second, there was a negative correlation between EGG HNR and EGG NNE. Finally, the mean value of HNR of normal Korean adults was $28.8\pm2.7$ dB, that of NNE -$11.7\pm3.9$ dB, that of EGG HNR $32.9\pm4.6$ dB, and that of EGG NNE $-30.3\pm4.6$ dB.

• 한국의류학회지
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• 제33권8호
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• pp.1190-1202
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• 2009

A 3D body scan measurement (SM) is used as an alternative to physical measurements (PM) as the information for designing industrial products. This study compared the mean difference (MD) between SM and PM by gender and analyzed the causes of the difference. The data used in this study were the scan measurements and physical measurements of adults aged twenty to seventy years old of the fifth Size Korea survey. The results of this study are as follows: 1. The comparison of MD between men and women for all subjects: The measurement of the significant differences between men and women were height, neck base girth, chest girth, under-bust girth, waist girth, armscye girth, back length, and foot length. The causes of difference are the difference of body shape. 2. The comparison of MD between men and women by BMI groups: Many measurements had significant differences between men and women at normal weight and overweight but underweight. Some measurements had significant differences only at a specific BMI group because the body shape difference between men and women is revealed clearly in the group. The comparison of MD between men and women by age groups: The measurements that show significant difference at more than four age groups were neck girth, chest girth, under-bust girth, waist girth, armscye girth, and foot length. The height and abdomen girth had a significant difference in the age range of 20's and 30's. There were measurements that increase MD with an increase in age; under-bust girth and lateral shoulder length for women and lateral shoulder length for men. This comparison of MD between men and women provide the correct guidelines for the use of SM.

• Imaging Science in Dentistry
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• 제33권3호
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• pp.171-178
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• 2003

Purpose: The purpose of this study was to report the reproducibility of intra-observer and inter-observer consistency of cephalometric measurements using three-dimensional (3D) computed tomography (CT), and the degree of difference of the cephalometric measurements. Materials and Methods: CT images of 16 adult patients with normal class I occlusion were sent to personal computer and reconstructed into 3D images using V-Works 3.5/sup TM/(Cybermed Inc., Seoul, Korea). With the internal program of V-Works 3.5/sup TM/, 12 landmarks on regular cephalograms were transformed into 21 analytic categories and measured by 2 observers and in addition, one of the observers repeated their measurements. Intra-observer difference was calculated using paired t-test, and inter-observer by two sample test. Results: There were significant differences in the intra-observer measurements (p < 0.05) in four of the categories which included ANS-Me, ANS-PNS, Cdl-Go (Lt), GoL-GoR, but with the exception of Cdl-Go (Lt), ZmL-ZmR, Zyo-Zyo, the average differences were within 2 mm of each other. The inter-observer observations also showed significant differences in the measurements of the ZmL-ZmR and Zyo-Zyo categories (p < 0.05). With the exception of the Cdl-Me (Rt), ZmL-ZmR, Zyo-Zyo categories, the average differences between the two observers were within 2 mm, but the ZmL-ZmR and Zyo-Zyo values differed greatly with values of 8.10 and 19.8 mm respectively. Conclusion: In general, 3D CT images showed greater accuracy and reproducibility, with the exception of suture areas such as Zm and Zyo, than regular cephalograms in orthodontic measurements, showing differences of less than 2 mm, therefore 3D CT images can be useful in cephalometric measurements and treatment planning.

• Fisheries and Aquatic Sciences
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• 제17권3호
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• pp.361-367
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• 2014

Cuttlefish Sepia esculenta are commercially important in Korea. Assessments of their biomass currently depend on fishery-landings data, which may be biased. Towards fishery-independent acoustic surveys of cuttlefish, target strength (TS) measurements at 70 and 120 kHz were made of 23 live cuttlefish, in early May 2010. The fish were caught by traps in the inshore waters around Geojedo, Korea. The TS were measured using split-beam echosounders (Simrad ES60 and EY500, respectively). The cuttlefish mantle lengths (L) ranged from 15.6 to 23.5 cm (mean L=17.8 cm) and their masses (W) ranged from 335 to 1020 g (mean W=556.1 g). Their mean TS values at 70 and 120 kHz were -33.01 dB (std=1.39 dB) and -31.76 dB (std=2.15 dB), respectively. The mean TS at 70 kHz was 0.17 dB higher than the TS-length relationship resulting from a least-squares fit to the data ($TS=24.67{\log}_{10}L(cm)-64.03$, $r^2$ = 0.52, N=23). The mean TS at 120 kHz was 0.45 dB higher than the fitted TS-length relationship ($TS=40.59{\log}_{10}L(cm)-82.96$, $r^2$ = 0.58, N=23). The differences between the mean TS values and an equation regressed from all of the TS measurements at both frequencies ($TS=24.92{\log}_{10}L(cm)-4.92{\log}_{10}{\lambda}(m)-22.82$, $r^2$ = 0.86, N=46) was 0.22 dB at 70 kHz and 0.31 dB at 120 kHz, respectively.

• 한국의류학회지
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• 제29권12호
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• pp.1595-1607
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• 2005

3차원 스캐너를 통한 인체 측정치는 다양한 분야에서 사용되고 있다. 본 연구는 이러한 3차원 측정치의 정확성과 신뢰도를 조사하기 위한 것이다. 이를 위해 TECMATH사의 VITUS 전신 스캐너로 인체를 측정, ScanWorX Body Measure 소프트웨어를 이용하여 항목을 측정 한 값과 직접 인체측정 에 의해 얻어진 값을 비교하였다. 피험자는 평균 체형의 미국 여대생 25명이며 기준 자세와 일상생활에 많이 쓰이는 $135^{\circ}$ 양팔들기, 어깨 구부리기, 어깨 들어올리기의 3가지 동적 자세를 실험 동작으로 하여 체표의 길이 및 둘레의 변화를 측정하였다. 기준 자세와 135"양팔 들기에 대한 측정치 비교에서 두 가지 측정법에 의한 항목들의 차이는 $-2\~20mm$였으나 두 동작 모두에서 목둘레만이 유의한 차이가 있는 것으로 나타났다. 또한 길이항목보다 둘레항목에서 좀 더 큰 차이를 보였다. 실험 동작에 의해 상반신 18개의 측정항목들은 유의한 체표변화를 나타내었으며 특히 어깨길이, 겨드랑앞벽사이길이, 겨드랑뒤벽사이길이 그리고 견봉사이길이에서 뚜렷한 변화가 나타났다. 그러나 두 측정 법에 따른 체표변화 차이는 없었다. 어깨 구부리기와 어깨 들어올리기 동작시에는 스캔 측정을 3회 반복함으로써 3차원 측정치의 신뢰도를 조사하였는데 모든 항목에서 3회 반복된 측정치가 통계적으로 동일한 것으로 나타났다. 또한 ScanWorX소프트웨어의 가상적 도구인 Body Measure와 자동 프로그램인 ScanWorX Tailor의 측정치를 비교한 결과 자동 측정치가 더 큰 값을 보였고 사용한 프로그램에 따른 유의한 차이를 나타내는 항목들이 나타났다. 이상의 결과로 3차원 인체 측정기를 사용함으로써 짧은 시간에 동작을 촬영하고 이에 대한 측정치를 얻을 수 있어 편리함과 신뢰도에 있어서 장점을 가짐을 확인할 수 있었다. 그러나 좀 더 다양한 분석과 정확한 결과를 얻기 위해서는 의복 분야에 유용한 자동 프로그램의 개발과 3차원 인체 측정기간의 호환성의 문제들이 요구된다고 할 수 있다.

• 한국산학기술학회논문지
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• 제17권2호
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• pp.227-232
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• 2016

3D 인체형상자료는 인체 적합성이 우수한 제품과 생활공간을 만들기 위해 다양한 분야에서 활용되고 있다. 본 연구는 한국인 인체치수조사 보급사업에서 2013년에 수집한 청소년층 3차원 측정 자료를 기반으로 한국 청소년의 대표 인체치수를 산출하고 대표 인체치수와 가까운 3D 인체형상자료를 선별하는 방법을 제공한다. 먼저 여러 측정항목으로 이루어진 다차원 벡터공간을 요인분석을 통해 둘레성분과 길이성분의 2차원 벡터공간으로 투영하였다. 다음으로 2차원 성분공간에서 마할라노비스 거리를 이용하여 대표 인체치수와 이에 가까운 3D 인체형상자료를 선별하였다. 2차원 성분공간에 나타난 청소년기의 성장패턴을 고려하여 남자는 4개의 연령그룹으로 여자는 3개의 연령그룹으로 구분하였다. 성분점수 계수행렬의 열벡터에 대응하는 고유형상을 이용하여 남자는 13개 측정항목, 여자는 14개 측정항목에 대한 대표 인체치수를 연령그룹별로 계산하였다. 여기서 구한 대표 인체치수와 3D 인체형상자료는 3차원 대표 형상을 만드는 데에 매우 유용하다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제2권2호
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• pp.147-155
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• 2002

This paper describes RF front-end transceiver chipset for the dual-mode operation of PCS-Korea and IMT-2000. The transceiver chipset has been implemented in a $0.25\mutextrm{m}$ single-poly five-metal CMOS technology. The receiver IC consists of a LNA and a down-mixer, and the transmitter IC integrates an up-mixer. Measurements show that the transceiver chipset covers the wide RF range from 1.8GHz for PCS-Korea to 2.1GHz for IMT-2000. The LNA has 2.8~3.1dB NF, 14~13dB gain and 5~4dBm IIP3. The down mixer has 15.5~16.0dB NF, 15~13dB power conversion gain and 2~0dBm IIP3. The up mixer has 0~2dB power conversion gain and 6~3dBm OIP3. With a single 3.0V power supply, the LNA, down-mixer, and up-mixer consume 6mA, 30mA, and 25mA, respectively.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.873-876
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• 2005

A low noise amplifier(LNA) using electro-magnetic field simulator is designed in standard 0.25um CMOS process. Integrated spiral inductor is simulated using EM field solver. Then LNA is simulated with active device, capacitor and simulated inductor by EM field solver. A S11 and S21 of -15.45dB and 17.8dB at 2.3GHz as simulation results was achieved. A Noise Figure is 2.92dB. And Measurements show a S11 and S21 of -12.4dB and 17.8dB at 2.3GHz. A Noise Figure of 3.3dB was achieved.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.291.2-291.2
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• 2016

3D semiconductor material of silicon that is used throughout the semiconductor industry currently faces a physical limitation of the development of semiconductor process technology. The research into the next generation of nano-semiconductor materials such as semiconductor properties superior to replace silicon in order to overcome the physical limitations, such as the 2-dimensional graphene material in 2D transition-metal dichalcogenide (TMD) has been researched. In particular, 2D TMD doping without severely damage of crystal structure is required different conventional methods such as ion implantation in 3D semiconductor device. Here, we study a p-type doping technique on tungsten diselenide (WSe2) for p-channel 2D transistors by adjusting the concentration of hydrochloric acid through Raman spectroscopy and electrical/optical measurements. Where the performance parameters of WSe2 - based electronic device can be properly designed or optimized. (on currents increasing and threshold voltage positive shift.) We expect that our p-doping method will make it possible to successfully integrate future layered semiconductor devices.