• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제49권6호
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• pp.450-456
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• 2000

In this paper, we proposed a novel control method which uses the internal impedance angles as a control parameter to drive traveling wave type ultrasonic motor. An impedance characteristic of the ultrasonic motor is obtained by analysis of the equivalent circuits including the external inductor used to generate the coupled resonance. The phase angle of internal impedance to achieve optimal control performance is derived. For the tracking of impedance angle, an information of phase difference is obtained from the applied voltage and current. The high speed phase difference detector is designed to monitor the phases of ultrasonic motor. The effectiveness of the proposed control scheme is clarified by experiments.

• 한국기계가공학회지
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• 제11권4호
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• pp.111-117
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• 2012

Dust collecting performance of axial-vane type cyclone for oil mist was analyzed in this study. For predicting cut diameter size of cyclone, the number and angle of vane ($tan{{\beta}_2}^{\prime}$) was simulated by CFD. As the result, $tan{{\beta}_2}^{\prime}$ was decreased as the number of vane was increased and the angle of inclination(${{\beta}_2}^{\prime}$) decreased, and it cause strong swirl flow. Therefore, it could be confirmed that as the number of vane was increased and the angle of inclination was decreased, cut diameter size was decreased. Also, by verifying the results of CFD through experiment, the cut diameter size could be $2{\mu}m$ at $4m^3/min$ of flow rate.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.116-118
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• 2001

It is important to determine of tower type whether suspension or tension tower in overhead transmission lines. When we select to tower type, we have need to check of swing angle for suspension string sets. And jumper wire of T/L in the strong wind area have to analysis of swing angle in order to clearance or length of tower arms. This paper is summarized the methods to calculate of swing angle for suspension string sets and jumper wires, and is calculated the swing angle. The calculated result have proposed to improved design specifications of overhead transmission line.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.1540-1549
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• 2009

Shear properties of geosynthetic/geosynthetic and geosynthetic/soil were evaluated from direct shear tests. The type of geosynthetic is Velcro which is effective for geosynthetic interface and make up for the weakness of sandbag. In this study, the cohesion and the angle of internal friction of each interface was estimated. The test results showed that the cohesion and the angle of internal friction of the geosynthetics depended on the amount of normal stress, the type of the geosynthetics used, and combinations of the geosynthetics and soils. Finally, by comparing the apparent cohesion and the friction angle of the geosynthetics, the applicability to design was identified.

• ETRI Journal
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• 제38권1호
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• pp.195-205
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• 2016

This paper presents a novel follicular unit (FU) classification method based on an angle variation of a boundary vector according to the number of hairs in several FU images. The recently developed robotic FU harvest system, ARTAS, classifies through digital imaging the FU type based on the number of hairs with defects in the contour and outline profile of the FU of interest. However, this method has a drawback in that the FU classification is inaccurate because it causes unintended defects in the outline profile of the FU. To overcome this drawback, the proposed method classifies the FU's type by the number of variation points that are calculated using an angle variation a boundary vector. The experimental results show that the proposed method is robust and accurate for various FU shapes, compared to the contour-outline profile FU classification method of the ARTAS system.

• Journal of Magnetics
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• 제22권1호
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• pp.7-13
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• 2017

The magnetoresistance (MR) properties of antiferromagnetic (AFM) IrMn based giant magnetoresistance-spin valve (GMR-SV) was investigated in view point of the artificial rotation effect of ferromagnetic (FM) layer in the plane induced by an applied field during the post annealing temperature. The MR curves measured with an azimuthal angle region of ${\phi}=0^{\circ}-360^{\circ}$ are depended on the annealing temperature and the magnetization easy axis of two free NiFe layers and two pinned NiFe layers in dual-type GMR-SV film. Especially, the annealing temperature and sample rotation angle(${\theta}$ ) maintained to the magnetic sensitivity (MS) of 1.4 %/Oe with an isotropic region angle of $110^{\circ}$ are $100^{\circ}C$ and $90^{\circ}$, respectively.

• 한국정밀공학회지
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• 제4권3호
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• pp.44-51
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• 1987

In metal cutting various types of chips are produced in consequence of cutting conditions. Flow-type chips have been studied in most cases because they are easier to be analyzed, but the actual surfaces of chips are not smooth, but crushed. This paper deals with saw-toothed chips, special types of flow-type chips, which have deep concaves and high convexes and sharp angles on the free surface. I tried to establish the theory of saw-toothed chip mechanism through experimental observation, that is, the mathmatical model of the cutting energy and cutting mechanism through the geometrical observation of the chips by using a microscope. The results obtained are as follows: 1. The mechanism of saw-toothed chips is diffenent from that of general flow-chips. 2. In the case of saw-toothed chips, the shear angle must be measured by the hypotenuse angle and the rake angle, and the shear angle is more affected by the rake angle than by the hypotenbuse angle. 3. The friction angle is represented by .beta. = . pi. /4+ .alpha./ sub n/- .phi. which is different from Merchant's equation. 4. The pitch and the slip are greatly influenced by depth of cut, but the influence of the rake angle on it is small. 5. The normal stress and the shear stress on the shear plane decrease with the increase of the cutting depth, and they are almost independent on the variation of a rake angle. 6. The unit friction energy on the tool face, the unit shear energy on the shear plane, and the total cutting energy per unit volume decrease with the increase of rake angle and cutting depth.

• 대한치과보철학회지
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• 제14권1호
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• pp.35-40
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• 1976

The author observed the positional relationship of maxillary cuspid to ala-lacrimal duct line in the 594 Koreans(329 male, 265 female) who had relatively normal teeth arrangement, aged 16 to 70. The relationship of ala-lacrimal duct line to the distal angie of maxilly cuspid of the subjects were classified as follows; Type A : Ala-lacrimal duct line was lotated more medially than the distal angle of maxillary cuspid. Type B : Ala-lacrimal duct line coincided with the distal angle of maxillary cuspid. Type C: Ala-lacrimal duct line was located more distally than the distal angle of maxillary cuspid. The occlusal relationship of the maxillary first molar to the mandibular first molar of the subjects were classified as follows; Group I : Group of neutrocclusion relationship. Group II : Group of distocclusion relationship. Group III : Group of mesiocclusion relationship. The obtained results were as follows; 1) The positional relationship of maxillary cuspid to ala-lacrimal duct line were as follows; (Male) Type A: $68.5%{\pm}1.58m%$, Type B: $22.5%{\pm}2.30m%$, Type C: $9.1%{\pm}\1.58m%$ (Female) Type A : $64.5%{\pm}2.94m%$, Type B: $26.5%{\pm}2.71m%$, TypeC: $8.9%{\pm}1.73m%$ 2) Ala-lacrimal duct line located more distally in group II and group III than group I at the point of the positional relationship of upper and lower first molar. 3) Average distance and standard deviation in type A were as follows; (Male) Right: $2.17mm.{\pm}1.01mm.$ Left: $2.27mm.{\pm}1.02mm.$ (Female) Right: $2.06mm.{\pm}0.70mm.$ Left: $2.24mm.{\pm}0.80mm.$ 4) Average distance and standard deviation in type C were as follows; (Male), Right: $1.47mm.{\pm}0.85mm.$ Left: $1.52mm.{\pm}0.97mm.$ (Female) Right: $1.04mm.{\pm}0.44mm.$ Left: $1.26mm.{\pm}0.89mm.$ The results of 3) and 4) had no significant difference between the male and female.

• 복식문화연구
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• 제5권4호
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• pp.112-129
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• 1997

This research, focused on the curved of the lower body, designated abdomen and hip gradient, crotch depth and crotch width the factors for which are able to influence on the appearence and the function of Divided Skirt and analized the changes when that were applied to a real pattern, and so the purpose of this research is to show the basic documents needed to design a Divided Skirt pattern fitting with the wear purpose and usage. The following are the results of this research. 1. The abdomen and hip gradient turned out as the most influential factor on the appearance and the function of Divided Skirt. The pattern of which the abdomen and hip gradient was designated as vertical zero degree, showed an excellent appearance and in case of function, the pattern of which thw angle of the abdomen and hip gradient of human body type was applied to itself without a particular designation turned out excellent. 2. In case of crotch depth, the pattern which had crotch depth＋2㎝, had a better appearance but influced nothing on function. 3. The factor of crotch width didn\`t have any influence on the appearance and function of Divided Skirt. 4. Referring to the results of the above, the Divided Skirt pattern of which the appearance and the function turned excellent, had the angle of abdomen gradient 4 degrees, the angle abdomen gradient 4 degrees, the angle of hip gradient/2+2.5 degrees, crotch depth+2㎝ and crotch width following human body type. In case of Divied Skirt worn when going out, the pattern which had the angle of abdomen and hip gradient vertical zero degree, crotch depth+2㎝ and crotch width following human body type, turned out suitable. Also, the suitable pattern of Divided Skirt for working had the abdomen and hip gradient following human body type, crotch depth+2㎝ and covering girth diameter/2±1㎝.

• Journal of Trauma and Injury
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• 제18권1호
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• pp.64-69
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• 2005

Purpose: We report the radiologic and the clinical results for surgical treatment of calcaneal fractures involving the subtalar joint. Methods: We evaluated the findings of radiographs and computed tomographs of 39 patients (40 cases) with intra-articular calcaneal fractures. The fractures were treated with open reduction via an extended lateral approach and internal fixation using a plate. We assessed the radiologic results, such as the $B{\ddot{o}}hler$ angle, the Gissane angle, and the height/width ratio. We assessed the clinical results based on the critieria of Salama et al. Results: According to the Essex-Lopresti classification, 9 cases were classified as tongue type and 31 cases as joint depression type. According to the Sanders classification, 10 cases were classified as type IIA, 4 cases as IIB, 16 cases as IIIAB, 4 cases as IIIAC, and 6 cases as type IV. The mean preoperative $B{\ddot{o}}hler$ angle was 7.7, the mean postoperative $B{\ddot{o}}hler$ angle was 21.1, and the mean last follow-up $B{\ddot{o}}hler$ angle was 16.8. Clinical results classified as 10 excellent, 13 good, 11 fair, and 6 poor. Conclusion: In the treatment of intra-articular fractures of the calcaneus, open reduction via an extended lateral approach seems to be a useful method in that it can provide direct exposure of the subtalar joint with little morbidity.