• 한국항행학회논문지
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• 제28권1호
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• pp.116-122
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• 2024

본 논문에서는 ILS (instrument landing system) 로컬라이저 전력증폭기의 변조도, 출력, 그리고 위상 변화량 규격의 요구성능을 도출하기 위하여, 시스템의 주요 성능 중에서 course structure와 course width를 연구하였다. Course structure의 편차 규격(± 5 uA)을 만족하기 위한 CSB (carrier with sideband) 증폭기의 변조신호 DDM (difference in depth of modulation) 편차 규격을 ± 1 uA(0.001 DDM)로 규격화하였다. CSB 30 W 전력증폭기를 설계하였고, 변조도 보상회로를 통하여 동작운용 출력범위(45 dBm ~ 35 dBm)에서 SDM (sum in depth of modulation)은 40% ± 0.1%, DDM은 ± 0.0005 DDM의 특성을 얻었다. 그리고 course width와 displacement sensitivity 규격에 대하여 시뮬레이션으로 분석하고, 가장 엄격한 규격인 운용개시 점검시에 적용되는 ± 0.1 ° 변화량을 적용하여, SBO (suppressed with sideband only) 증폭기의 출력변동은 ± 2 mW, 위상은 ± 3 ° 로 규격화하고 특성을 만족하였다. 출력과 온도에 따른 보상회로를 적용하여, 안정적인 변조지수, 출력, 그리고 위상 특성을 얻었다.

• Journal of Multimedia Information System
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• 제6권4호
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• pp.245-250
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• 2019

In this paper, we propose an ellipsoid modeling method for coding of a face depth picture. The ellipsoid modeling is firstly based on a point of a nose tip which is defined as the lowest value of the depth in the picture. The proposed ellipsoid representation is simplified through a difference of depth values between in the nose tip and in left or right boundary point of the face. Parameters of the ellipsoid are calculated through coordinates and depth values to minimize differences from the actual depth pixels. A picture is predicted by the modeled ellipsoid for coding of the face depth picture. In simulation results, an average MSEs between the face depth picture and the predicted picture is measured as 20.3.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.385-390
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• 2001

The thermal crack in mass concrete is mainly due to the difference of concrete temperature, which is generated by hydration heat of cement. As the thickness of mat foundation increases, the difference of temperature becomes bigger. The purpose of this study is to estimate the optimum placing depth. The temperature of real mat foundation was observed and the thermal analysis by Finite Element Method was executed. Finally, the crack index according to the placing depth was estimated.

• Journal of Periodontal and Implant Science
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• 제31권2호
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• pp.489-499
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• 2001

Bone graft and guided tissue regeneration have been used for the regeneration of periodontal tissue which is the ultimate goal of periodontal treatment. Recently, it was reported that some kind of growth factors were used for regeneration. Platelet rich plasma was researched that it could increase the density of bone and the rate of bone regeneration. For that, 25 patients which have pocket depth more than 5mm at any of 6 surfaces, of healthy patient without any systemic disease were treated. $Biogran^{?}$ Were grafted into 14 infrabony pockets as controls, and $Biogran^{(R)}$ with PRP were inserted into 31 infrabony pockets. And then, follwing evaluations were made at the end of 1, 3 and 6 months. 1. There was no statistical difference between control and experimental group in pocket depth, gingival recession, minimum probing attachment level and maximum probing attachment level at preoperation(p>0.05). 2. Decrease in probing pocket depth were reduced to 3.32mm for experimental group and 2.71mm for control group. The decrease was evident at the end of 1 month, they were 2.97mm and 2.29mm,and it was statistically difference(p<0.05). 3. Gingival recession was increased by 0.55mm in experimental group and 0.50mm in control group, it was evident at the end of 1 month. And it was statistically difference(p<0.05). 4. Minimum probing attachment level was increased by 0.35mm in experimental group and 0.36mm in control group, it was statistically difference(p<0.05). 5. Maximum probing attachment level was decreased by 3.19mm in experimental group and 2.93mm in control group, it was statistically difference(p<0.05). 6. There was no statistical difference between control and experimental group in pocket depth, gingival recession, minimum probing attachment level and maximum probing attachment level(p>0.05). There was statistical difference in decrease of pocket depth between pre-operation and 1 month after post-operation(p<0.05). In conclusion, bone graft using $Biogran^{?}$ and bone graft using $Biogran^{?}$ With platelet rich plasma were both effective in treatment of infrabony pocket, bone graft using $Biogran^{?}$ With platelet rich plasma was more effective in early soft tissue healing.

• 자원환경지질
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• 제35권6호
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• pp.567-573
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• 2002

2차원 MT모델링을 수행하여 지자기 수직탐사(GDS)에서의 차이 지시자의 유용성을 조사하였다. 해양과 육지에 위치하는 전도체의 전자기적인 상호 결합 정도는 차이 지시자의 유용성을 판단하는 기준으로서 본 연구에서는 해양과 전도체의 공간적인 위치와 주기에 따른 상호 결합을 조사하였다. 전도체가 지표에 존재하는 경우 해양에서 충분히 떨어져 있거나 사용된 주기가 장주기일 때 차이 지시자가 유용하였고, 전도체가 심부에 매몰된 경우에는 상호 결합이 약해 전 주기에서 차이 지시자가 물리적인 의미를 가졌다. 그러나 전도체가 지표로부터 심부까지 확장되어 있는 경우 상호 결합이 장주기까지 강하게 영향을 미쳐 차이 지시자의 유용성을 확신할 수 없다. 따라서 획득된 유도 지시자로 부터 해양처럼 이미 알고 있는 전도체의 효과를 제거하기 위해서는 수치 모델링을 통한 전도체 간의 상호 결합에 대한 정보가 요구되며 상호 결합이 큰 경우 차이 지시자의 해석은 정확하지 않으므로 주의해야한다.

• 한국진공학회지
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• 제12권3호
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• pp.162-167
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• 2003

시료에 주입된 이온의 깊이방향에 따른 농도분포를 알아보기 위하여 시료표면을 sputtering 하면서 튀어나온 주입된 이온을 depth profiling한다. Depth profiling 측정 시에 깊이방향에 영향을 주는 sputtering rate가 변화하는 효과를 SRIM simulation을 이용하여 계산하였다. 시료에 이온이 주입하게 되면 시료의 원자밀도는 약간 증가하게 되는데, 그 결과로 sputtering yield가 변화하게 된다. 이러한 변화가 결과적으로 depth profile 측정시에 깊이방향에 영향을 줄 수 있는 sputtering rate를 변화시키는 원인이 된다. SRIM(Stopping and Range of Ions in Matter) Monte Carlo simulation code를 사용하여 이온주입에 의한 시료의 원자밀도의 변화에 따른 sputtering yield를 구하여 sputtering rate를 계산하고, 그 차이가 depth profiling 측정에서 깊이방향 분포에 영향을 줄 수 있다는 것을 확인하였다.

• The Korean Journal of Pain
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• 제10권1호
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• pp.73-76
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• 1997

Background : Epidural anesthesia is now accepted as a popular technique for pain relief and anesthesia. However, accidental dural puncture may occur during placement of the epidural needle. This study was undertaken to evaluate difference of the epidural depth between parturients and non-parturients. Method : Eighty non-parturients receiving epidural anesthesia were assigned to group I, and eighty parturients whose body weight had not yet increased over 15 kg from pregnancy were assigned to group II. With patients in lateral decubitus position, 18 guage Tuohy needle was punctured by approaching at $L_{3-4}$ interspace. Epidural space was identified using loss-of-resistance to air technique. Result : Epidural depth was 4.18 cm and 4.25 cm in group I and group II respectively. There was no significant statistical difference in body mass index(BMI) and ponderal index(PI) (p<0.05), nor in epidural depth between the two groups. Conclusion : Epidural needle need not be placed deeper in parturients than in nonparturients.

• Journal of Acupuncture Research
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• 제33권2호
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• pp.89-96
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• 2016

Objectives : The aim of this study is to investigate the needling depth of Hwangmun (BL51) and Jisil (BL52) retrospectively using an L-spine MRI. Methods : We measured the shortest distance from the skin to transversalis fascia at both sides of Hwangmun and Jisil, and analyzed the difference between male and female using a student t-test, and between the left and right sides with a paired t-test. Results : In the case of males, the average depth of left Hwangmun was $48.24{\pm}10.16mm$, and that of right was $47.23{\pm}9.59mm$ ; left Jisil was $56.91{\pm}9.00mm$ and right was $55.74{\pm}8.75mm$. In the case of females, the average depth of left Hwangmun was $42.26{\pm}9.29mm$, and that of right was $41.63{\pm}9.32mm$ ; left Jisil was $49.21{\pm}10.77mm$ and right was $48.41{\pm}11.38mm$. The depth of male insertion was deeper than that of female in Jisil, but there was no significant difference according to gender in Hwangmun. Conclusion : For males, the needling depth of left Hwangmun is 37.21 ~ 68.23 mm and right is 36.91 ~ 70.50 mm, while left Jisil is 42.97 ~ 70.84 mm and right is 43.75 ~ 72.00 mm. For females, the needling depth of left Hwangmun is 26.80 ~ 68.28 mm and right is 25.70 ~ 65.59 mm, while left Jisil is 30.94 ~ 79.06 mm and right is 28.13 ~ 77.27 mm.

• 대한치과기공학회지
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• 제27권1호
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• pp.89-95
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• 2005

In the manufacture of ceramo-metal crown, difference of fracture strength according to the metal depth has been known to be an important influence on enough intensity and internal stress to endure an occlusion-pressure as well as aesthetics of rehabilitating similar colour such as natural teeth. Depth of ceramic material could be determined by that of metal in three groups: first case of thin depth, second case of thick depth, and third case of constant depth. For the enhancement of the fracture strength between metal and ceramic materials and aesthetic satisfaction, a study on the bonding force, fracture strength, and aesthetics have been required more. In this study, therefore metal coping were made in three groups of A, B and C by using both ceramic powder of Norithe and metal of Columbium, which have been used primarily in the market. A group was made in $0.2mm\times10mm\times10mm$, B group was made in $0.4mm\times10mm\times10mm$, and, C group was made in $0.8mm\times10mm\times10mm$, respectively. The number of metal coping in each group was 10, and total sample numbers used in this study were 30 metal copings. After these metal coping tissue were in the process of build-up in 1.5mm constant depth of porcelain, firing, and glazing, the fracture strength about each metal coping tissue was investigated using oil press. It was found that the average values of durable occlusion pressure for separation of ceramic material in the porcelain fused to metal crown (PFM) in the each group showed the increasing order of A group (30 bar), B group (42 bar), and C group (44 bar), respectively. Proper depth of metal coping in the PFM was considered to be 0.4mm in the B group because this metal size showed higher durable property to the occlusion pressure and better coupling strength in the ceramo-metal crown.

• 드라이브 ㆍ 컨트롤
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• 제17권4호
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• pp.125-132
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• 2020

The objective of this study was to analyze the axle load of a rice transplanter when planting rice seedlings at different working load conditions to select a suitable gear stage and a constant planting depth for rice seedlings. In this study, there are four levels of planting distances (26, 35, 43, and 80 cm) and three planting depths (low, medium, and high) with two gear stages (1.3 and 1.7 m/s). Axle loads and required planting pressures were analyzed statistically. It was observed that axle torques were increased with increasing planting depths for both gear stages, meaning that axle torques were directly proportional to planting depths for both gear stages. It was also observed that required planting pressures had a significant difference between planting distances. Planting pressures also showed significant difference according to gear stage and planting depth. These results indicate that planting pressures were directly proportional to both gear stage and planting depth. Results revealed that the automatic depth control system of a rice transplanter could not guarantee a constant planting depth as supplied pressures were variable. This indicates that a control algorithm is needed to ensure a constant planting depth. In the future, a control algorithm will be developed for an automatic depth control system of a rice transplanter to improve its comprehensive performance and efficiency.