• 제목/요약/키워드: loop length

검색결과 309건 처리시간 0.03초

Three-dimensional analysis of the anterior loop of the inferior alveolar nerve in relation to the growth pattern of the mandibular functional subunit

  • Yoon, Seungkyu;Kim, Jae-Young;Jeong, Cheol-Hee;Park, Jengbin;Huh, Jong-Ki;Park, Kwang-Ho
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제40권
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    • pp.30.1-30.6
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    • 2018
  • Background: The purpose of the present study was to investigate the differences in the position and shape of the anterior loop of the inferior alveolar nerve (ALIAN) in relation to the growth pattern of the mandibular functional subunit. Methods: The study was conducted on 56 patients among those who had undergone orthognathic surgery at the Gangnam Severance Hospital between January 2010 and December 2015. Preoperative computerized tomography (CT) images were analyzed using the Simplant OMS software (ver.14.0 Materialise Medical, Leuven, Belgium). The anterior and inferior lengths of ALIAN (dAnt and dInf) and each length of the mandibular functional subunits were measured. The relationship between dAnt, dInf, and the growth pattern of the mandibular subunits was analyzed. Results: The length of the anterior portion of ALIAN (dAnt) reached 3.34 ± 1.59 mm in prognathism and 1.00 ± 0.97 mm in retrognathism. The length of the inferior portion of ALIAN (dInf) reached 6.81 ± 1.33 mm in prognathism and 5.56 ± 1.34 mm in retrognathism. The analysis of Pearson's correlation coefficiency on all samples showed that the lengths of functional subunits were positively correlated with the loop depth. The length of the symphysis area in prognathic patients was positively correlated with the anterior loop depth (p = 0.005). Conclusions: Both the anterior and inferior length of ALIAN are longer in prognathic patients. Especially, it seems to be associated with the growth of the symphysis area.

Cone beam형 전산화단층영상을 이용한 하악관의 전방고리 및 이공에 관한 연구 (Observation of the anterior loop and mental foramen of the mandibular canal using cone beam computed tomograph)

  • 고광준;김경아
    • Imaging Science in Dentistry
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    • 제39권2호
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    • pp.81-87
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    • 2009
  • Purpose: To evaluate the anteroposterior length and buccal angle of the anterior loop, and the size and location of the mental foramen using cone beam computed tomography (CBCT). Materials and Methods: 100 CBCT images from 87 adults (43 males and 44 females) ranging in age from 20 to 73 years (average 50 years) with edentulous ridge of the mandibular premolar region were obtained. Axial, sagittal, coronal images were reconstructed from Dental and Block Images of CBCT. The anteroposterior length, shape and buccal angle of the anterior loop, and the size and location of the mental foramen were calculated from reconstructed images of axial, sagittal and coronal CBCT. Results: The anteroposterior length and buccal angle of the mental canal was 4.0${\pm}$1.2mm, 37.8${\pm}$11.60$^{\circ}$respectively. The loop type with straight course was the most common shape of the mental canal. The location of the mental foramen below the apex of the lower second premolar (78%) was the most common. The maximum size of the mental foramen was 4.6${\pm}$1.0 mm in width and 3.0${\pm}$0.6 mm in height. The inner size of the mental canal was 2.6${\pm}$0.6 mm in width and 2.1 mm${\pm}$0.4 mm in height. Conclusion: CBCT is useful to evaluate the anterior loop and mental foramen of the mandibular canal. Safe guideline of 4 mm from the most anterior point of the mental foramen is recommended for implant and surgical treatment. (Korean J Oral Maxillofac Radiol 2009; 39: 81-7)

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지상파 DMB용 다중 권선 Loop 안테나 (Multi-Turn Circular Loop Antenna for Portable Terrestrial DMB)

  • 손원국;최익권
    • 한국전자파학회논문지
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    • 제19권5호
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    • pp.501-505
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    • 2008
  • 이 논문에서는 휴대 장치의 지상파 DMB용 안테나로 다중 권선 loop 안테나를 제안한다. 제안된 안테나는 크기가 작으면서도 지상파 DMB 대역에서 충분한 수신 전력을 확보하도록 권수는 80회, 그리고 직경은 4 mm로 하였으며, 또한 높은 전달 함수 특성을 갖도록 품질 계수를 1로 하였다. 제작된 안테나는 길이가 30 mm로 소형이며, 이득은 약 -15 dBd로 길이 190 mm의 상용 지상파 DMB 모노폴 안테나와 비슷한 수신 능력을 가짐을 측정을 통해 확인하였다.

A Feedback Linearization Control of Container Cranes: Varying Rope Length

  • Park, Hahn;Chwa, Dong-Kyoung;Hong, Keum-Shik
    • International Journal of Control, Automation, and Systems
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    • 제5권4호
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    • pp.379-387
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    • 2007
  • In this paper, a nonlinear anti-sway controller for container cranes with load hoisting is investigated. The considered container crane involves a planar motion in conjunction with a hoisting motion. The control inputs are two (trolley and hoisting forces), whereas the variables to be controlled are three (trolley position, hoisting rope length, and sway angle). A novel feedback linearization control law provides a simultaneous trolley-position regulation, sway suppression, and load hoisting control. The performance of the closed loop system is shown to be satisfactory in the presence of disturbances at the payload and rope length variations. The advantage of the proposed control law lies in the full incorporation of the nonlinear dynamics by partial feedback linearization. The uniform asymptotic stability of the closed-loop system is assured irrespective of variations of the rope length. Simulation and experimental results are compared and discussed.

운동매질내에서의 Circula Loop Antenna의 방사특성(II) (Radiation Characteristics of a Circular Loop Antenna in Moving Media.)

  • 최병하
    • 대한전자공학회논문지
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    • 제9권2호
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    • pp.17-23
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    • 1972
  • 본논문에서는 운동매질내에서 크기가 파장과 동등정도이거나 그 이상인 circular loop antenna의 방사특성을 전류분포가 정현파적인 경우에 대하여 고찰하였다. 고찰결과로는 방사특성이 매질속도의 영향을 받는다는 사실과 그 영향으로는 정지매질의 radiation pattern 과 비교하여 방사지향성이 loop antenna면에 평행인 매질속도성분에만 영향을 받고 수직성분속도에는 무관하며 radiation pattern의 최대지향성은 loop면에 평행인 속도성분방향으로 이동하고 이와 반대방향으로는 Pattern의 크기가 증가하게 된다. 또 이와 같은 운동매질의 영향은 매질속도도가 오고 전류주파수가 높을수록 antenna의 직경이 클수록 더욱 현저하게 된다는 사실을 알게 되었다.

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위편성 니트 소재의 선호도에 관한 연구 (Studies on the preference of weft knit fabrics)

  • 주정아
    • 한국생활과학회지
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    • 제14권4호
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    • pp.665-671
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    • 2005
  • This study aims to examine the effect of structural properties, subjective textures, sensibilities, and objective handle on the preference for weft knit fabrics, and then to provide useful information in planning and designing knit fabrics through predicting the preference. We made 20 plain knit fabrics, as specimens, with a combination of 5 kinds of wool/rayon fiber contents and 4 kinds of stitch loop length. For the subjective evaluation of textures, sensibilities, and preference, we used the questionnaire that had been developed in the previous study. The data analysis was conducted with Pearson's correlation analysis, ANOVA, Duncann multiple range test and regression analysis. The results are as follows: In relationship of structural properties and preference, we could not recognize any difference in whole ranges of wool/ rayon fiber contents and in 7.5mm and less stitch loop length. On the other hand, we could find the decrease of preference in over 7.5mm stitch loop length. As to subjective textures and sensibilities, a multiple regression analysis of preference indicated a higher determination coefficient by sensibilities than by textures. But there were little correlation between a objective handle and preference of weft knit fabrics.

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Non-inverted Meniscus식 모세관 구조물을 이용한 소형 루프히트파이프에 관한 실험적 연구 (A Study on the Miniature Loop Heat Pipe with Non-inverted Meniscus type Capillary Structure)

  • 정원복;박수용
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회B
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    • pp.2142-2147
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    • 2007
  • Experimental study was conducted to evaluate the performance of a miniature loop heat pipe (MLHP) with non-inverted meniscus type capillary structure. All parts of MLHP in this study were made of copper including the capillary structure and the distilled water was used as a working fluid of MLHP. The outer diameter of evaporator was 9 mm and its length was 119 mm. The effective pore size of the capillary structure was 30 micron and its porosity was 60%. The vapor transport line, the liquid transport line and the condenser were consisted of single 4.0 mm copper tube. The distance between the evaporator and the condenser region was 200 mm and the length of the loop was 969 mm. This MLHP was operated successfully at any orientation but the gravity highly influenced the thermal performance of the MLHP. The maximum thermal load was 130 watts at the bottom heat mode and the 20 watts at the top heat mode.

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자기저항 헤드용 MR/TbCo 박막의 자기교환 결합 (Magnetic Exchange Coupling at The Interface of MR/TbCo Thin Films)

  • 서정교;조순철
    • 한국자기학회지
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    • 제6권1호
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    • pp.1-6
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    • 1996
  • MR/TbCo 박막 계면의 자기교환 결합의 특성을 시뮬레이션 하기 위해서 박막내에 존재 하는 자기 에너지를 최소화 하여 자화의 방향을 구하였다. 수치해석 방법으로는 Newton법과 Gauss-Seidel 방법이 이용되었다. TbCo의 이방성 상수에 비례적으로 자기 이력곡선의 폭이 변하고, TbCo 천이영역의 두께가 얇을수록 자기이력곡선이 벌어지지 않았다. 특히 TbCo 천이영역의 두께가 $400\;\AA$ 일때 단일 곡선(보자력 10 Oe 이하)을 보였다. 또한 계면 교환 결합상수가 작을수록 천이영역의 두께가 얇을 때와 비슷한 곡선을 보였고, 완전히 결합된 상태의 1/100 정도 일때, 단일 곡선을 보였다. 제작한 박막의 자기이력곡선과 비교하여 계면교환 결합상수를 추정할 수 있었다.

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Optimization of Energy Conversion Loop in Switched Reluctance Motor for Efficiency Improvement

  • Li, Jian;Qu, Ronghai;Chen, Zhichu;Cho, Yun-Hyun
    • Journal of Electrical Engineering and Technology
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    • 제8권3호
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    • pp.565-571
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    • 2013
  • This paper presents an effective method to improve efficiency of switched reluctance motor by optimizing energy conversion loop. A nonlinear analytical model which takes saturation account is developed to calculate inductance and flux-linkage. The flux-linkage curve is studied to calculate the co-energy increment to obtain the optimum exciting current. For a given cross-section, the exciting current at which co-energy increment is maximum was found to be constant while stack length varies. Then the energy conversion loop was optimized by varying the stack length and turns of windings. The constraints during optimization were that motor was excited by the maximum increment co-energy current and the energy in the loop was determined by rated power of motor. Dynamic finite element analysis was used to evaluate the efficiency of various models and the comparison of results shows promising effects of the proposed method. Experiment was also conducted to validate the simulation result.

휴대 단말기용 연장 루프안테나 (Extended Loop Antenna for the Mobile Handset)

  • 손태호;류황
    • 한국ITS학회 논문지
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    • 제12권2호
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    • pp.30-37
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    • 2013
  • 본 논문에서는 지난 호 브랜치 루프안테나 BLA(Branch Loop Antenna)에 이어 휴대 단말기용 연장 루프안테나를 설계한다. 사각형 루프에 연장 루프를 추가한 ELA(Extended Loop Antenna)를 소개하고, 휴대 단말기에 적용될 수 있음을 보인다. 연장 루프 소자를 사각형 루프안테나 상단 및 좌우양단에 추가하고, 길이를 조절하여 낮은 공진 주파수를 얻는다. 연장 루프에 의한 다중 공진을 얻고, 접속위치와 길이로부터 원하는 대역을 얻는다. 설계한 ELA를 구현한 후 측정으로부터, CDMA/GSM의 낮은 주파수 대역에서 평균이득 -3.0~-1.46dBi 및 50.15~71.41% 효율의 양호한 특성을 얻었고, DCS/USPCS/WCDMA의 높은 주파수 대역에서는 평균이득 -8.28~-1.7dBi 및 14.87~67.68% 효율을 얻었다.