• Title/Summary/Keyword: loop length

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A STUDY ON THE CHANGES OF THE ELASTIC PROPERTIES TN LOOPED WIRES BY VARIABLE FACTORS (변환요소에 따른 LOOPED WIRE의 탄성 변화에 관한 연구)

  • Na, Yong-In;Kim, Sang-Cheol
    • The korean journal of orthodontics
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    • v.25 no.3 s.50
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    • pp.263-271
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    • 1995
  • The purpose of this study nab to evlauate and compare the effect of the variable factors of wire on the elastic properties of looped rectangular wire. Five variable factors were presented-material(Hi-T, blue Elgiloy), wire size(.016'$\;\times\;$.022', .018'$\;\times\;$.025'), loop length(15mm, 20mm), loop configuration(open loop, closed loop), gabling (non-gable, gable). So, the total 256 specimens were divided into 32 groups, and each of those nab pulled on Instron testing machine. The load-deflection curve of each wire obtained, from which force, range in elastic limit, and stiffness were computed and analyzed statistically. The results were obtained as follows : 1. All of the variable factors - wire material, size, loop length loop configuration, and gabling - took a significant effect on load-deflection rate of looped wire. 2. The force at elastic limit was the smallest in the group of Hi-T, .016'$\;\times\;$.022', 20mm loop length, open loop, non-gable, and the largest in the group of blue Elgiloy, .018'$\;\times\;$.025', 15mm loop length, closed loop, non-gable. 3. The range at elastic limit was the smallest in the group of Hi-T, .018'$\;\times\;$.025', 15mm loop length, open loop, non-gable, and the largest in the group of HI-T, .016'$\;\times\;$.022', 20mm loop length, closed loop, gable. 4. Loop configuration and loop length were the most effective factors on the elastic properties of looped wires, and gabling was the least effective.

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Assessment of the anterior loop of the mandibular canal: A study using cone-beam computed tomography

  • Nascimento, Eduarda Helena Leandro do;Pontual, Maria Luiza dos Anjos;Pontual, Andrea dos Anjos;Perez, Danyel Elias da Cruz;Figueiroa, Jose Natal;Frazao, Marco Antonio Gomes;Ramos-Perez, Flavia Maria de Moraes
    • Imaging Science in Dentistry
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    • v.46 no.2
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    • pp.69-75
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    • 2016
  • Purpose: Sufficient area in the interforaminal region is required for dental implant placement, and the anterior loop of the mandibular canal is located within the limits of this area. The aim of this study was to evaluate the prevalence and extent of the anterior loop in a Brazilian sample population using cone-beam computed tomography (CBCT). Materials and Methods: CBCT images from 250 patients (500 hemimandibles) obtained for various clinical indications were randomly selected and evaluated to determine the presence and length of the anterior loop. The length of the anterior loop was then compared based on gender, age, and the side of the mandible. The data were analyzed using the Pearson chi-square test and linear regression analysis. Results: An anterior loop was identified in 41.6% of the cases, and its length ranged from 0.25 mm to 4.00 mm (mean, $1.1{\pm}0.8mm$). The loop had a greater mean length and was significantly more prevalent in males (p=0.014). No significant differences were found between the right and left sides regarding length (p=0.696) or prevalence (p=0.650). Conclusion: In this study, a high prevalence of the anterior loop of the mandibular canal was found, and although its length varied greatly, in most cases it was less than 1 mm long. Although this is a prevalent anatomical variation, safety limits for the placement of implants in this region cannot be established before an accurate evaluation using imaging techniques in order to identify and preserve the neurovascular bundles.

The Relationship of Structural Properties, Subjective Textures and Sensibilities of Knit Fabrics - Wool/Rayon Fiber Contents and Loop Length - (니트 소재의 구성 특성과 주관적 질감 및 감성의 관계 - 양모/레이온 혼용률 및 편환장 변화를 중심으로 -)

  • Ju, Jeong-Ah;Ryu, Hyo-Seon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.8 s.145
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    • pp.1158-1167
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    • 2005
  • The purpose of this study is to examine the effect of structural properties of plain knit fabrics on the subjective textures and sensibilities of consumers. We investigated the relationship of subjective textures and sensibilities according to fiber contents of wool/rayon and stitch loop length. We made 20 plain knit fabrics, as specimens, with a combination of 5 kinds of fiber contents and 4 kinds of stitch loop length. A factor analysis showed that subjective textures are classified into 3 categories with $R^2=70.32\%$: 'surface-rough', 'drapable', 'bulky' and 'elastic' and subjective sensibilities into 3 categories with $R^2=68.12\%$: 'stable/neat', 'feminine/elegant' and 'natural/comfortable'. The fiber contents of wool/rayon had a positive and linear relation with 'surface-rough', but had a relatively non-linear one with 'bulky' and 'elastic' categories of textures, and 'feminine/elegant' of sensibilities. The stitch loop length had a linear influence on 'drapable' and 'stable/neat', but had a non-linear influence on other subjective textures and sensibilities.

A Study on Dimensional Properties of Warp Knitted Fabrics with Various Lengths of Underlap (Underlap 길이에 따른 경편포의 칫수특성에 관한 연구)

  • 남은우;김석근;최재우
    • Textile Coloration and Finishing
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    • v.11 no.6
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    • pp.51-58
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    • 1999
  • The dimensional properties on polyester warp knitted fabrics with various lengths of underlap were studied. The results indicated that loop density increased with decreasing loop length and loop density of satin warp knitted fabric are a little higher than that of reverse satin warp knitted fabrics at a constant loop length. As the distance of underlap becomes shorter, the weight per unit area and thickness increases, the bulkiness decreases and the shrinkage of knitted fabrics become larger toward wale in satin warp knitted fabric and toward the course in reverse satin warp knitted fabric.

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Phase Controlled Thin Film Loop Antenna for Multi-media Devices (멀티미디어단말기용 박막형 위상제어루프 안테나)

  • Shin, Cheon-Woo
    • Journal of Korea Multimedia Society
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    • v.12 no.7
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    • pp.971-978
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    • 2009
  • The paper is a phase controlled loop antenna for multi-media devices. We developed a phase control loop pattern arrangement methods for loop antenna in mobile devices like as a cell phone and PCS, WCDMA. In the loop antenna pattern, arrange close adhesive the loop antenna pattern $180^\circ$ cycle in wave length, the radiated electro-magnetic wave from close adhesive loop pattern become to coherent wave than the phase controlled loop antenna has high efficiency and high radiation gain. To acquire a wide band width on phase controlled loop antenna, we arrange a multiple phase controlled loop pattern that has a different length each other. Different length for each other loop pattern cause a different frequency that we can acquire a wide band width for loop antenna from close adhesive phase control. In experiment, we designed a CDMA850 mobile multi-media antenna in 20mm$\times$20mm area thickness 0.4mm, the radiation efficiency is over 60% and radiation gain is over 0dBi.

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The Decision of the Optimal Shape of Inductive Loop for Real-Time Traffic Signal Control (실시간 교통신호제어를 위한 루프 검지기의 최적형태결정에 관한 연구)

  • 오영태;이철기
    • Journal of Korean Society of Transportation
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    • v.13 no.3
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    • pp.67-86
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    • 1995
  • It requires the detector system which can collect highly reliable traffic data in order to perform the real-time traffic signal control. This study is to decide the optimal shape of inductive loop for the real-time traffic signal control .This loop is located at the stopline in the signalized intersection for DS(Degree of Saturation) control. In order to find out the optimal shape of loop, 6types of experiments were performed . The results of the basic experiments of loops are as follows ; -the optimal number of turns for loop is 3 turns. -the impedance values of the loop detectors are similar to that of NEMA standards -the 1.8${\times}$4.5M loop is excellent for sensitivity in actual detection range of car length comparing to other shape of inductive loops. At the experimental of establishments of the optimal loop shape, it found that 1.8 4.5M loop has the highest values of $\DeltaL$ comparing to other types of loops, It means that the range of Lead-in cable length of this loop. And this loop is highly reliable in occpupancy time. Conclusivley, the 1.8${\times}$4.5M inductive loop is the optimal solution as a stop line loop detector for real -time traffic signal control.

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Dual Loop Optoelectronic Oscillator with Acousto-Optic Delay Line

  • Kim, Tae Hyun;Lee, Sangkyung;Lee, Chang Hwa;Yim, Sin Hyuk
    • Journal of the Optical Society of Korea
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    • v.20 no.2
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    • pp.300-304
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    • 2016
  • A dual loop optoelectronic oscillator (OEO) based on an acousto-optic modulator (AOM) for single mode operation with an acousto-optic delay line is demonstrated in this paper. When the OEO operates, the free spectral range is a function of the total loop length of the OEO, which is mainly dependent on the propagation time of the acoustic wave in the AOM. Due to the huge difference in the magnitude between the speed of light and the acoustic velocity in the AOM, the effective loop length converted to light-propagation length of the OEO increases to 3.8 km. With 150 MHz oscillation frequency, phase noise of -118 dBc/Hz at 10 kHz frequency offset, and -140 dBc/Hz at 200 kHz frequency offset, is achieved.

Effects of Fiber Contents and Loop Length of Weft Knit on Subjective Texture and Preference-Using SEM- (위편성물의 혼용률 및 편환장이 주관적 질감과 선호도에 미치는 영향 -구조방정식 이용-)

  • Roh, Eui-Kyung;Ryu, Hyo-Seon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.31 no.7
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    • pp.1128-1138
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    • 2007
  • The purpose of this study is to develop the relationship model among subjective texture and preference of weft knit according to fiber contents of wool/rayon and loop length by integrating previous research work. SPSS and SEM method using AMOS program were used to analyze data which used to correlation matrix to be standardized. The texture of weft knit were classified into 4 categories: irregularity, flexibility, bulkiness, extensibility. The fiber contents of wool/rayon had effect positively on irregularity, bulkiness and extensibility and that had little effect on preference. The loop length had effect positively on irregularity, flexibility and extensibility and that had effect negatively on preference. This measurement model will be input for testing causal research model that can explain how fiber contents of wool/rayon and loop length of weft knit influence on subjective texture.

Performance Evaluation of Large Borehole Ground-Loop Heat Exchanger (저심도 대구경 지중열교환기의 설치조건에 따른 성능 연구)

  • Yoo, Gyu-Sang;Park, Il-Mun;Choi, Jae-Ho;Shin, Hyun-Joon
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.58-63
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    • 2009
  • A ground-loop heat exchanger for the ground source heat pump system is the core equipment determining the thermal performance and initial cost of the system. The size and performance of the heat exchanger is highly dependent on the ground thermal properties - the ground effective thermal conductivity, the borehole thermal resistance and the undisturbed ground temperature. Nowadays, precast concrete piles using steel reinforced precast concrete piles - energy piles - are used to reduce the installing cost of the ground-loop heat exchanger. We were carried out some tests to investigate the effects of some parameters such as borehole length, grouting materials and U-tube configuration of the energy piles. 4 concrete piles, each measuring $250mm{\sim}400mm$ in diameter and approx. 10m in length, and rigged with single spiral and 3 U-tube loop of $16mm{\times}2.3mm$ PB piping. The thermal response tests were conducted using a testing device for 4-different ground-loop heat exchangers. During the heating period, the energy piles absorb the heat of 0.89kW to 1.37kW.

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A Study on the Dimensional Characteristics of the Weft Knitted Fabrics with Bamboo Knitted Yarn (Bamboo사 평 편조직 위편성물의 형태안정성에 관한 연구)

  • Choi, Jae-Woo;Jang, Bong-Sik;Lee, Eun-Woo;Kim, Dong-Yeub
    • Journal of the Korean Society of Industry Convergence
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    • v.15 no.3
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    • pp.79-82
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    • 2012
  • Aim of this study is to investigate the dimensional characteristics of the weft knitted fabrics with Bamboo knitted yarn. This Bamboo knitted yarn was made of the biodegradability fiber. The structure of weft knitted fabrics that was utilized for this study is the plain stitch, which is the most basic structure among all weft knitted fabrics. The loop density, courses density, and wales density are more increased as the loop length is shorter. The loop density increased as pre-treatment process and dyeing process progressed after dry treatment process, and on the contrary, the heat setting process made it decreasing. After the dyeing process proceed, the loop density and the course density were displayed the highest values. When the knitted fabrics were fully relaxed, the loop density was $2000/in^2$, the courses density was 52/in, the wales density was 39/in.