• 대한기계학회논문집B
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• 제32권5호
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• pp.327-334
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• 2008

Effects of tube inclination on pool boiling heat transfer have been studied for the saturated water at atmospheric pressure. For the analysis, seven inclination angles varying from the horizontal to the vertical and two tube diameters(25.4 and 30.0 mm) are tested. According to the results, inclination angles result in much change on heat transfer. For the same wall superheat(about $5.3^{\circ}C$) the ratio between two heat fluxes for the $45^{\circ}$ inclined and the vertical has the value of more than five when the tube diameter is 25.4mm. As the inclination angle is increasing from the horizontal to the vertical direction heat transfer is gradually increasing because of the increase in liquid agitation. However the detailed tendency depends on the ratio between the tube length and the diameter.

• 소성∙가공
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• 제24권2호
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• pp.77-82
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• 2015

By investigating the practical use of trim punch configurations for shearing of vehicle panels, the current study first reviews the shearing angle as part of the shearing die design. Based on this review, four different types of trim punch shapes (i.e., horizontal, slope, convex, and concave type) and shearing angles(i.e., 0.76°, 1.53°, 2.29°, 3.05°, 3.81°) were investigated. In order to conduct shearing experiments, four types of trim punch dies were made. The four trim punch dies were tested under various conditions. The experiments used the four trim punch shapes and the five shearing angles. The shearing force varied by shape and decreased from horizontal, slope, convex, to concave for the same shearing angle. The magnitude of shearing force showed differences between the convex and the concave shapes due to the influence of constrained shearing versus free shearing. The test results showed that compared to the horizontal trim punch shearing force, the decrease of the slope, convex, and concave shearing forces were 22.6% to 60.4%. Based on the results, a pad pressure of over 30% is suggested when designing a shearing die.

• Nuclear Engineering and Technology
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• 제36권2호
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• pp.142-152
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• 2004

The liquid entrainment and vapor pull-through offtake model of RELAP5/MOD3 had been developed for SBLOCA (Small Break Loss of Coolant Accident). The RELAP5/MOD3 model for horizontal volumes accounts for the phase separation phenomena and computes the flux of mass and energy through a branch when stratified conditions occur in the horizontal pipe. In the case of CANDU reactor, this model should be used in the coolant flow of 95 feeders connected to the reactor header component under the horizontal stratification in header. The current RELAP5 model can treat the only 3 directions junctions; vertical upward, downward, and side oriented junctions, and thus improvements for the liquid entrainment and vapor pull-through model were needed for considering the exact angles. The RELAP5 off-take model was modified and generalized by considering the geometric effect of branching angles. Based on the previous experimental results, the critical height correlation was reconstructed by use of the branch line connection angle and validation analyses were also performed using SET. The new model can be applied to vertical upward, downward and angled branch, and the accuracy of the new correlations is more improved than that of RELAP5.

• 치과방사선
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• 제25권1호
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• pp.127-132
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• 1995

A number of panoramic radiographic images of the condylar head taken at various horizontal angulations were compared. A small artificial osteophyte was attached to the eight different portions of the condylar head and a small hole was created in four different portions of the condylar head. Three oral and maxillofacial radiologists evaluated the panoramic condylar images. The results were as follows : 1. Osteophytes in the superomedial, anterocentral and anterolateral portions could be detected easily, but those in the lateral, superolateral and medial portions were very hard to identify. 2. The greater the condylar horizontal angle, the easier it was to detect an osteophyte. But there was no statistically significant difference except between 0 and 40 degrees of horizontal angulation. 3. Holes in the anterocentral and superocentral portions could be detected easily, but those in the lateral and medial portions were very hard to identify. There were no differences between the various condylar horizontal angles.

• 전기의세계
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• 제17권3호
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• pp.43-56
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• 1968

The design of this antenna tower on the publication had been prepared by writer in order to compare with that of towers for power transmission line or to show the differences on designs existing on their design standards. The design of this antenna tower is also featuring on the following points; (1) the height of tower is 150meters high, (2) combined steel angles are adopted besides angles, (3) the direction of 45degree wind is taken account into design, (4) the additional stresses of horizontal members located in the bending points of main posts are contemplated though these additional stressess are not shown on stress diagram.

• The Journal of Advanced Prosthodontics
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• 제10권6호
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• pp.401-407
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• 2018

PURPOSE. When performing an occlusal procedure, it is recommended that the patient should be sitting straight with the head in a natural position. An inappropriate mandibular position caused by an incorrect occlusal record registration or occlusal adjustment can result in damaged teeth and cause functional disorders in muscles and temporomandibular joints. The purpose of this study was to clarify the influence of horizontal cephalic rotation on mandibular position by investigating the three-dimensional positions of condylar and incisal points. MATERIALS AND METHODS. A three-dimensional jaw movement measurement device with six degrees of freedom (the WinJaw System) was used to measure condylar and incisal points. The subjects were asked to sit straight with the head in a natural position. The subjects were then instructed to rotate their head horizontally $0^{\circ}$, $10^{\circ}$, $20^{\circ}$, $30^{\circ}$, $40^{\circ}$, $50^{\circ}$and $60^{\circ}$ in the right or left direction. RESULTS. The results indicated that horizontal cephalic rotation made the condyle on the rotating side shift forward, downward, and toward the inside, and the condyle on the counter rotating side shift backward, upward, and toward the outside. Significant differences in deviations were found for angles of rotation higher than $20^{\circ}$. The incisal point shifted in the forward and counterrotating directions, and significant differences were found for angles of rotation higher than $20^{\circ}$. CONCLUSION. The mandibular position was altered by horizontal cephalic rotations of more than $20^{\circ}$. It is essential to consider the possibility of deviation of the mandibular position during occlusal procedures.

• 건설안전기술
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• 통권47호
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• pp.56-62
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• 2008

In order to apply the Limit Equilibrium Method generally used for the slope stability analysis to the vertical excavation walls reinforced by soil-nailing, in this study, the Limit Equilibrium Method for the temporary shoring facilities reinforced by soil-nailing was proposed, which is based on the stability for the horizontal displacement. In this study, the relation of the internal friction angles of the ground and the vertical excavation depths was arranged, which is satisfying the stability on the horizontal displacement by using the verification of the Limit Equilibrium Method. And then, the rational reinforcing length of soil-nailing was proposed for the critical areas. In addition, the modified safety ratio satisfying the stability on the horizontal displacement was proposed, when the Limit Equilibrium Method was applied to the vertical excavation walls reinforced by soil-nailing.

• 한국지반공학회지:지반
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• 제6권4호
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• pp.7-18
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• 1990

본 연구에서는 안정된 암 표면으로부터 가까운 거리에 강성재료로 이루어진 수직 옹벽이 설치될 때, 옹벽 뒷면에 작용하는 발생토압 문제를 다루기 위해 Spangler-Handy가 제시한 식 및 Sokol-ovskii 응력특성법을 각각 수정하였다. 수정 된 해석방법들은 옹벽 및 암 뒷면에서의 벽 마찰각의 크기 를서로구분하여 고려하였으며,됫채움 구이 비점성토인 경우에 바깥쪽으로 움직이는 옹벽의 다양 한 이동형태 및 각각의 이동단계에 관련된 정적 및 동적수평토압 계산에 이용 가능하다. 수정된 Spangler-Handy 식 및 Sokolovskii 응력특성법의 적용범위(옹벽-암 사이의 거리 b와 옹벽 높이 H의 비를 서로비교하였으며, 또한 뒷채움 흙의 내부마찰각 및 옹벽 원면의 벽마찰각이 각 해석방법의 적용범위에 미치는 영향도 분석하였다. 아울러, b/H=0.3인 경우에 수정된 Spangler-Handy 식을 토대로 얻어진 계산치를 Frydman-Keissar이 밝힌 실험 치와 비교 하였으며, 비교를 통해 하단을 중심으로 한 옹벽의 다양한 회전이동 단계에서 발생토압의 크기가 잘 일치함을 알 수 있었다. 이외에도 옹벽 뒷면의 벽마찰각 및 수평가속계수가 정적 및 동적주동토압에 미치는 영향도 검토하였으며, 뒷채움 흙의 내부마찰각 및 수평가속계수의 크기가 다양할 때 적용 가능한 설계도표도 아울러 제시되었다.

• 치과방사선
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• 제20권1호
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• pp.19-27
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• 1990

The primary objective of this study was to analyze the hard and soft tissue profile and comparison of the both sexes in Korean adults using roentgenocephalometry. The subjects were 122 males and 116 females from 18 to 22 years of age selected on the basis of their excellent occlusion and harmonious profile. It was an investigation about the interrelationships in the angles which consisted of Frankfort horizontal plane (FH plane), Sella Nasion plane (SN plane), Nasal floor plane (NF plane) and Mandibular plane (Md plane) as reference planes, and of the axial inclinations of the upper anterior tooth to Nasal floor plane (NF Plane) and of the lower anterior tooth to Mandibular plane (Md Plane). Among the 14 categories estabilishied on the soft tissue land marks, the 6 categories were studied for the relationship to Frankfort horizontal plane (FH Plane), and the 8 categories were studied for the soft tissue contour. The results were as follows: 1. Among 8 measured angles in the hard tissue, the angle of FH-Md, NF-Md and SN-Md were greater in females than in males. 2. The axial inclinations of the anterior teeth to NF Plane and Md plane were slightly greater in males than In females. 3. Among 14 measured angles in the soft tissue, the angles of G-Sn-P and E-Pog-Sn were greater in males, and FH-G-Sn, GㆍSn-Sn. Pog and Pog-Sn-P were greater in females. 4. In males, the variability of measured values in both lips region were high.

• 한국안전학회지
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• 제27권2호
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• pp.84-91
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• 2012

This study evaluated three forces (lifting, pushing and twisting) required to maneuver the single-wheel barrows according to handle height, width, horizontal angle and vertical angle. The four independent variables were varied in two levels. Handle height was varies in two levels : 'knuckle height (KH)' and 'KH + 0.1 ${\times}$ stature'. The two handle widths were '1.5 ${\times}$ shoulder width (SW)' and '1.75 ${\times}$ SW'. Two angles of $0^{\circ}$ and $15^{\circ}$ were used for horizontal and vertical angles. The 24 factorial design was used in the experiment. Twelve healthy male students (undergraduate and graduate) participated in the experiment. Subjects exerted three forces (pushing, lifting, and twisting clockwise) in each experimental condition. The order of 16 treatment conditions was determined randomly. Results showed that the effects of the four factors were different according to three forces. While lifting and twisting forces were higher in 'knuckle height', the pushing force was higher in 'KH + 0.1 ${\times}$ stature' (p < 0.05). Lifting and pushing forces showed higher values in the horizontal angle $0^{\circ}$ than in $15^{\circ}$. Handle width and vertical angle showed no statistically significant main effects on three forces (p > 0.05). Results of this study could be used as basic data for the ergonomic design of handle variables of one- or two-wheel barrows.