• 한국정밀공학회지
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• 제14권6호
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• pp.52-63
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• 1997

Non-circular gear has a good velocity ratio in high speed and heavy load without any slip, moreover, it can transmit various motion, using simpler structure than link and cam, automation mechainism. In case of designing and manufacturing non-circular gear. I suggest one of references in applying non-circular gear to industrial plant, and suitable range of application by pressure angle curvature and angle ratio

• 산업기술연구
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• 제26권A호
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• pp.129-137
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• 2006

In this research, we made a one and two-dimensional analysis of numerical data collected from the bend curvature of a bended river section. According to the result from the numerical analysis, the inflow ＆ output angle caused a water level deviation which increased with an increase of the flood discharge. From the water level deviation of our two-dimensional numerical model, we obtained the maximum slope of 6,67% when the inflow and output angle was 105 degrees and the flood discharge was 500 CMS. As for the right side, the differences with the one-dimensional numerical model were reduced when the angle was more than $90^{\circ}$. As for the left side the differences were reduced when the angle was more than $105^{\circ}$. For a river with more than 90 degrees bend curvature, a hydraulic experiment would be more appropriate than a numerical analysis.

• Structural Engineering and Mechanics
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• 제83권1호
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• pp.19-29
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• 2022

The angle steel frame confined concrete columns (ASFCs) are an emerging form of hybrid columns, which comprise an inner angle steel frame and a concrete column. The inner angle steel frame can provide axial bearing capacity and well confining effect for composite columns. This paper presents the experimental and theoretical studies on the seismic behaviour of ASFCs. The experimental study of the 6 test specimens is presented, based on the previous study of the authors. The theoretical study includes two parts. One part establishes the section analysis model, and it uses to analyze section axial force-moment-curvature. Another part establishes the section moment-curvature hysteresis model. The test and analysis results show that the axial compression ratio and the assembling of steel slabs influence the local buckling of the angle steel. The three factors (axial compression ratio, content of angle steel and confining effect) have important effects on the seismic behaviour of ASFCs. And the theoretical model can provide reasonably accurate predictions and apply in section analysis of ASFCs.

• 산업기술연구
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• 제37권1호
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• pp.27-31
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• 2017

In this paper, we have extended the research on the infrared sensor which has been limited to the plane. The reflection mechanism of the light on the curved surface is analyzed according to the curvature change and the emitted angle of photodiode and verified through experiments. The difference in the curvature causes a difference in the measurement distance, and also changes the intensity of the light coming into the phototransistor, thereby causing a difference in the output voltage. However, the difference in the output voltage due to the curvature change can be solved by adjusting the emitted angle of the photodiode to minimize the spot area formed on the curved surface regardless of the curvature. Therefore, it is possible to measure the distance by using the infrared sensor regardless of the curvature by aligning the photodiode to the center of the curved surface and adjusting the angle of the photodiode.

• 척추신경추나의학회지
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• 제18권2호
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• pp.65-73
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• 2023

Objectives This case study aimed to investigate efficacy of Chuna manual therapy (CMT) on acute neck pain patients with abnormal cervical curvature. Methods CMT was administered to five patients with abnoraml cervical curvature in the Department of Korean Medicine Rehabilitation, College of Korean Medicine, Semyung University Korean Hospital from June 2018 to May 2023. Cervical angle, Jackson's angle, Jochumsen method, Ishihara index and visual analog scale (VAS) scores were evaluated before and after treatment. Results In cases 1, 2, 3, 4, and 5, the cervical angle, Jackson's angle, Jochumsen method, Ishihara index all increased, while VAS scores decreased after CMT. Conclusions The observed improvements suggest that CMT is effective in restoring the cervical curvature and alleviating neck pain in patients with acute neck pain.

• 대한추나의학회지
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• 제5권1호
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• pp.151-161
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• 2004

Objectives : To investigate and compare the curvature of the cervical spine of the patients with whiplash and insidious onset neck pain. Method : Clinical study carried out in 33 insidious onset neck pain outpatients and 34 whiplash onset neck pain inpatients in Conmaul Oriental Hospital. Cervical spine curvature was measured using five measuring Methods. Type of cervical spine curvature was analyzed by Jochumsen method. Ishihara Index. T-test was used to compare the cervical spine angle of the two groups. Results : The prevalence of 'straight' and 'kyphotic' cervical spines was 46.5% in the insidious onset cases and 26.47% in the whiplash onset cases. In Jackson's angle, Jochumsen method, Ishihara Index, and Park's method, angle of the Cervical spine curvature was significantly lower in the insidious onset cases. (P<0.01) Conclusion : The results suggest that the cervical spine of neck pain patients is 'straight' and 'kyphotic' and more significant in insidious onset cases.

• 대한기계학회논문집B
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• 제22권11호
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• pp.1591-1602
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• 1998

Simple spanwise distribution models of deviation angle and pressure loss coefficient due to the tip leakage flow are formulated for use in association with the streamline curvature method as a flow analysis. Combining these new models with the previous deviation and loss models due to secondary flow, a robust streamline curvature method is established for flow analysis of single-stage, subsonic axial turbines with wide ranges of turning angle, aspect ratio and blading type. At the exit from rotor rows, the flow variables are mixed radially according to a spanwise transport equation. The proposed streamline curvature method is tested against a forced vortex type turbine as well as a free vortex type one. The results show that the spanwise variations of flow angle, axial velocity and loss coefficients at rotor exit are predicted with good accuracy, being comparable to a steady three-dimensional Navier-Stokes analysis. This simple and fast flow analysis is found to be very useful for the turbine design at the initial design phase.

• 한방재활의학과학회지
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• 제19권4호
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• pp.115-126
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• 2009

Objectives : The aim of this study was to evaluate whether the foot pressure distribution correlates with the lumbo-sacral curvature, and the Oswestry Disability Index in chronic low back pain patients. Methods : We measured the fore foot pressure and the rare foot pressure using the foot analyzer in 28 women subjects with chronic low back pain. The lumbo-sacral curvature and the Oswestry Disability Index(ODI) were also measured. Results : 1. Subjects with higher ODI(%) had significantly lower Fore foot pressure/Rare foot pressure ratio(F/R ratio) (p<0.01). 2. Lumbar lordotic angle and Ferguson angle were inversely related to ODI(%) (p<0.05, p<0.01). 3. Lumbar lordotic angle and Ferguson angle were positively related to F/R ratio (all p<0.05). Conclusions : Using the Foot Analyzer(FA-48S, Tech storm Inc.) we have shown that F/R ratio has significant correlation with the lumbo-sacral curvature and the Oswestry Disability Index. These result suggest that the Foot analyzer may be used in assessing back pain in chronic low back pain patients.

• 척추신경추나의학회지
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• 제7권1호
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• pp.95-101
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• 2012

Objectives : This study is performed to evaluate the clinical effect of Chuna therapy on the neck pain associated with kypotic cervical curvature. Methods : This study carried out on two patients with neck pain & kyphotic cervical curvature who have received treatment in Department of Oriental Rehabilitation Medicine, Dong-seo Oriental Medical hospital from 4th April 2011 to 26th May 2012. Pre and post treatment, We evaluated the cervical angle, Jackson's angle, Jochumsen method, VAS and effective score of treatment. Results & Conclusions : Two patients who received Chuna treatment recovered cervical curvature and improved neck pain.

• EDISON SW 활용 경진대회 논문집
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• 제5회(2016년)
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• pp.228-233
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• 2016

Auxetic material is a material which has negative Poisson's ratio(NPR). Auxetic material shows some distinctive property like high energy absorbing property and high shear modulus. Among these, synclastic curvature is very interesting characteristic. When synclastic-curvature-material bends, it changes its shape like dome, contrary to non-auxetic material which changes its shape like saddle(anticlastic). This distinctive property could make it easy to manufacture curved structure like nose cone or wing panel in aerospace engineering. In this study, we studied a quantitative analysis about synclastic curvature of re-entrant panel with finite element model. We suggested a concept 'Degree of Synclasticity(DOS)', which means a ratio of curvature of load-direction and load-orthogonal direction. We studied the variation of DOS with two factor, unit cell inner angle(${\theta}$) and load position angle(${\phi}$). DOS decreases as ${\theta}$ increases because the unit cell goes out of auxetic-shape. As ${\phi}$ varies, DOS changes in a large range. So proper optimization of ${\phi}$ would be needed for application.