• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
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• pp.3-7
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• 2009

The amount of incident rays over inclination according to direction has been widely utilized as important data in installing solar thermal systems. To optimize the incident solar radiation, the slope, that is the angle between the plane surface in question and the horizontal, and the solar azimuth angles are needed for these solar thermal systems. This is because the performance of the solar thermal systems in much affected by angle and direction of incident rays. Recognizing that factors mentioned above are of importance, actual experiment on the moving route of the sun have been performed in this research to obtain the angle of inclination with which the maximum incident rays can be absorbed. After all, the standard for designing highly optimized solar thermal systems will be provided for designers and employees working in the solar collector related industries.

• Structural Engineering and Mechanics
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• 제34권3호
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• pp.377-390
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• 2010

This paper studies fracture initiation direction of two parallel non-coplanar cracks of equal length. Using the dislocation pile-up modelling, singular integral equations for two parallel cracks subjected to mixed-mode loading are derived and the crack-tip field including singular and non-singular terms is obtained. The kinking angle is determined by using the maximum hoop stress criterion, or the ${\sigma}_{\theta}$-criterion. Results are presented for simple uniaxial tension and biaxial loading. The biaxiality ratio has a noticeable influence on crack growth direction. For the case of biaxial tension, when neglecting the T-stress the crack branching angle is overestimated for small crack inclination angles relative to the largest applied principal stress direction, and underestimated for large crack inclination angles.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.228-230
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• 2003

This paper presents a utility interactive photovoltaic generation system with the angle of inclination and direction. This paper summarizes the results of these efforts by offering a snapshot of the configuration of photovoltaic in residential applications. The status of photovoltaic system components and interconnection and safety equipment will be summarized. This system is able to variation the angle of inclination and direction. Hence this paper discuss only results that might be useful for generation power.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2001년도 추계학술대회 논문집(Proceeding of the KOSME 2001 Autumn Annual Meeting)
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• pp.8-14
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• 2001

The purpose of this study is to elucidate heat characteristics according to inclination angle of the hot flat plate at the spray cooling. As results of this experiment, the heat flux, the heat transfer coefficient and the cooling speed are increased as the liquid volume flux and subcooled temperature go up. And as the inclination angle of the heat transfer surface is increased, the cooling speed on the inclined flat plate becomes faster. It means that the cooling ability is increased because droplets were excluded by gravity.

• 대한치과교정학회지
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• 제18권1호
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• pp.7-24
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• 1988

The stable occlusion in function is thought as important as the esthetics in form, in order to preserve the healthy oral condition. The stable occlusion requires the harmony between the condylar guidance factors and the anterior guidance factors. The aim of this study was to evaluate the quantitative relationship between the condylar guidance factors and the anterior guidance factors, estimating statistically the measurement of the condylar paths by Pantronic and those of the anterior guidance factors, craniofacial morphology by roentgenocephalometry in 46 relatively good functional occlusion. The results of this study were as follows. 1. The measurements of the protrusive condylar path inclinations were $36.41^{\circ}$ in the right, $35.63^{\circ}$ in the left, $36.28^{\circ}$ in the mean. The measurements of Fisher's angles were $8.17^{\circ}$ in the right, $6.43^{\circ}$ in the left, $6.87^{\circ}$ in the mean. 2. The anterior facial height and the lower anterior facial height made a negative correlation with the protrusive condylar path inclination. 3. The articular eminence angle relative to the artificial articulator plane showed a positive correlation with the maximum protrusive condylar path. 4. SNA and SNB made a negative correlation with the articular eminence angle, and AAP-GoMe, AAP-DcGn, the facial height ratio had a positive correlation with the articular eminence angle. 5. The angulation of maxillary incisor lingual slope, overbite and the ratio of overbite to overiet showed a positive correlation with the articular eminence angle. 6. The angulation of maxillary incisor lingual slope , overbite, and the ratio of overbite to overjet made a positive correlation with the inclination of occlusal plane, functional occlusal plane. 7. Overbite and the ratio of overbite to overjet had a positive correlation with the angulation of maxillary incisor lingual slope. 8. The anterior guidance factors were more influenced by the mean protrusive condylar path inclination and the maximum Fisher's angle, and the regression equations of those were made.

• The Journal of Korean Physical Therapy
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• 제13권1호
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• pp.127-137
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• 2001

Low back pain is significant problem in today's society, with lifetime incidence rate reported between 50% and 90%. Many factors associated with LBP are reported. The purpose of this studies were to be evaluated static standing posture aberrations in chronic LBP in comparison with healthy individuals. The samples including 80 subjects recruited to the following two groups:patients and control(normal) Questionnaires were completed by 40 LBP patients and 40 controls at the department of Physical Therapy, Saejong neurosurgical clinic in Taegu city from October 1, 1999 to March 30, 2000. The angle of lumbar lordosis was measured on lateral x-ray films with standing position. In LBP groups. the mean degree of lumbar lordosis, sacral inclination, and lumbosacral joint angle were 29.9 ${\pm}$ 9.3, 34.8 ${\pm}$ 8.2, and 12.7 ${\pm}$ 5.7 respectively. Control groups, the mean degree of lumbar lordosis, sacral inclination and lumbosacral joint angle were 35.3 ${\pm}$ 7.8, 34.9 ${\pm}$ 6.4 and 12.5 ${\pm}$ 4.3 respectively. there were significantly decreaseds in lumbar lordosis in Low back pain group. lumbar lordosis on the working posture had significant differences among groups(sitting position patients 31.4 ${\pm}$ 9.3, standing position patients 29.4 ${\pm}$ 9.3, sitting position control 35.0 ${\pm}$ 6.4, standing position control 35.5 ${\pm}$ 8.8, respectively) (p=0.034). sacral inclination on the working posture had differences among groups(sitting position patients 35.9 ${\pm}$ 8.7.standing position patients 33.6 ${\pm}$ 7.6, sitting position control 33.9 ${\pm}$ 5.9. standing position control 35.6 ${\pm}$ 6.8, respectively). lumbersacral joint angle on the working Posture had differences among groups(sitting position patients 12.0 ${\pm}$ 5.6, standing position patients 13.4 ${\pm}$ 5.9, sitting position control 11.2 ${\pm}$ 3.0. standing position control 13.4$^{\circ}$, respectively).

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2017년도 추계학술대회
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• pp.232-233
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• 2017

본 연구에서는 선미 터널을 적용한 비대칭 고속 쌍동선을 수치해석 기법을 통해 선체의 유체동역학적 성능을 평가하였다. 선미터널 형상은 터널 출구 형상에 경사각에 따라 구분하였으며, 총 3가지 형상($0^{\circ}$, $3^{\circ}$, $6^{\circ}$)을 사용하였다. 결론적으로, 저항성능의 경우, 전 속도 구간에서 $0^{\circ}$ 경사각의 선미터널은 기존 대비 4.8-17.9% 감소한 것을 확인하였다. 하지만 $3^{\circ}$와 $6^{\circ}$경사각을 가진 선미터널은 각각 기존대비 5-14%와 5-29%의 저항이 증가하는 것을 확인하였다. 이와 달리, 트림각의 경우, $0^{\circ}$경사각은 전 속도구간에서 기존선형과 유사한 경향을 보였으나, $3^{\circ}$와 $6^{\circ}$경사각의 경우 각각 FnV=1.54이후에서 평형상태 유지 및 계속적인 감소 형태를 보였다. 이와 같은 형상은 터널 출구 영역에 경사각을 증가하는 것이 저항성능 측면에서 다소 악영향을 발생하지만 운항성능 측면에서는 기존대비 개선됨을 보여준다.

• Imaging Science in Dentistry
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• 제41권3호
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• pp.95-100
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• 2011

Purpose : The purpose of this study was to compare asymmetric mandibular prognathism individuals with symmetric mandibular prognathism individuals using a new alternate spherical coordinate system. Materials and Methods : This study consisted of 47 computed tomographic images of patients with mandibular prognathism. The patients were classified into symmetric and asymmetric groups. Mandibular and ramal lines were analyzed using an alternate spherical coordinate system. The length as well as midsagittal and coronal inclination angle of the lines was obtained. The bilateral differences of the spherical coordinates of the facial lines were statistically analyzed in the groups. Results : There were significant differences between the groups in bilateral difference of the length and midsagittal inclination angle of the lines (p<0.05). The bilateral difference of the length and midsagittal inclination angle of the lines has significant correlation with chin deviation (p<0.05). Conclusion : The new alternate spherical coordinate system was able to effectively evaluate facial lines. The bilateral difference of lengths and midsagittal inclination of the facial lines might contribute to the facial asymmetry in mandibular prognathism individuals.

• Advances in concrete construction
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• 제14권5호
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• pp.299-307
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• 2022

Cement-based matrixes have low tensile strength and negligible ductility. Adding fibres to these matrixes will improve their mechanical properties and make these composites suitable for structural applications. Post-cracking tensile strength of steel fibers-reinforced cementitious composite materials is directly related to the number of transverse fibers passing through the crack width and the pulling-out behavior of each of the fibers. Therefore, the exact recognition of the pullout behavior of single fibers is necessary to understand the uniaxial tensile and bending behavior of steel fiber-reinforced concrete. In this paper, an experimental study has been carried out on the pullout behavior of 3D (steel fibers with totally two hooks at both ends), 4D (steel fibers with a total of four hooks at both ends), and 5D (steel fibers with totally six hooks at both ends) in which the fibers have been located either perpendicular to the crack width or in an inclined manner. The pullout behavior of the mentioned steel fibers at an inclination angle of 0, 15, 30, 45, and 60 degrees and with embedded lengths of 10, 15, 20, 25, and 30 millimetres is studied in order to explore the simultaneous effect of the inclination angle of the fibers relative to the alongside loading and the embedded length of fibers on the pullout response in each case, including the maximal pullout force, the slip of the maximum point of pullout force, pullout energy, fiber rupture, and concrete matrix spalling. The results showed that the maximum pullout energy in 3D, 4D, and 5D steel fibers with different embedded lengths occurs at 0 to 30° inclination angles. In 5D fibers, maximum pullout energy occurs at a 30° angle with a 25 mm embedded length.

• Advances in concrete construction
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• 제13권1호
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• pp.45-69
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• 2022

This paper investigates the shear behavior of reinforced concrete haunched beams (RCHBs) without stirrups. The research objective is to study the effectiveness of the ideal steel fiber (SF) ratio, which is used to resist shear strength, besides the influence of main steel reinforcement, compressive strength, and inclination angles of the haunched beam. The modeling and analysis were carried out by Finite Element Method (FE) based on a software package, called Atena-GiD 3D. The program of this study comprises two-part. One of them consists of nine results of experimental SF RCHBs which are used to identify the accuracy of FE models. The other part comprises 81 FE models, which are divided into three groups. Each group differed from another group by the area of main steel reinforcement (A_s) which are 226, 339, and 509 mm². The other parameters which are considered in each group in the same quantities to study the effectiveness of them, were steel fiber volumetric ratios (0.0, 0.5, and 1.0)%, compressive strength (20.0, 40.0, 60.0) MPa, and the inclination angle of haunched beam (0.0°, 10.0°, and 15.0°). Moreover, the parametric analysis was carried out on SF RCHBs to clarify the effectiveness of each parameter on the mechanical behavior of SF RCHBs. The results show that the correlation coefficient (R²) between shear load capacities of FE proposed models and shear load capacities of experimental SF RCHBs is 0.9793, while the effective inclination angle of the haunched beam is 10° which contributes to resisting shear strength, besides the ideal ratio of steel fibers is 1% when the compressive strength of SF RCHBs is more than 20 MPa.