• Journal of Mechanical Science and Technology
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• v.16 no.9
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• pp.1102-1111
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• 2002

The study focuses on the heat transfer performance of two-phase closed thermosyphons with plain copper tube and tubes having 50, 60, 70, 80, 90 internal grooves. Three different working fluids(distilled water, methanol, ethanol) are used with various volumetric liquid fill charge ratio from 10 to 40%. Additional experimental parameters such as operating temperature and inclination angle of zero to 90 degrees are used for the comparison of heat transfer performance of the thermosyphon. Condensation and boiling heat transfer coefficients, heat flux are obtained using experimental data for each case of specific parameter. The experimental results are assessed and compared with existing correlations. The results show that working fluids, liquid fill charge ratio, number of grooves and inclination angle are very important factors for the operation of thermosyphons. The relatively high rate of heat transfer is achieved when the thermosyphon with internal grooves is used compared to that with plain tube. The optimum liquid fill charge ratio for the best heat transfer performance lies between 25% and 30%. The range of the optimum inclination angle for this study is 20$^{\circ}$～30$^{\circ}$ from the horizontal position.

• Tribology and Lubricants
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• v.39 no.2
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• pp.56-60
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• 2023

In this study, we evaluate the anisotropic flow of droplets according to the directionality of asperities. We manufacture a mold with an inclined hole by adjusting the jig angle using a high-power diode laser. Using the manufactured mold, we prepare specimens for wettability studies by the micro molding technique. We fabricate twelve kinds of surfaces with micro-asperities inclined at 0°, 15°, 30°, and 45° for asperity pitches of 100 ㎛, 200 ㎛, and 300 ㎛. We evaluate the static and dynamic behaviors of the droplets as a function of the asperities pitch and inclination angles. The anisotropic effect increases as the pitch increases between asperities, and the anisotropic flow characteristics increase as the inclination angle of the asperities increases. On the surface with hole pitches of 100 ㎛ and 200 ㎛, the contact angle of the droplet shows high hydrophobicity at approximately 160°, but on the surface with the 300-㎛ hole pitch, the contact angle is approximately 110°, indicating that the hydrophobic effect rapidly reduces. Additionally, when the inclination angle of the asperities is approximately 30°, the left and right contact angle deviations of the droplet are the lowest, showing that the roll-off angle is relatively low.

• Journal of Korean Society of Water and Wastewater
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• v.12 no.4
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• pp.106-111
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• 1998

In this paper,to know sedimentation efficiency compared with sedimentation efficiency's experiment result by general and inclination plate settler, its and fin stick of inclination plate. Experiment result is inclination plate settler increase sedimentation efficiency's 6.96% than general settler, When fin stick of inclination plate is the optimum condition of one side, inclination plate's angle $60^{\circ}$, fin's width 67mm, fin's interval 200mm, sedimentation efficiency of many experimental condition increase 6.63% than inclination plate settler. A studdy on the site plottage through the result, Water inclination plate settler of the present's application reduce 30% of its than general settler. According to the above statements, fin stick of inclination plate's sedimentation efficiency is 0.95 times of inclination plate settler's. Concluding remarks, Fin stick of inclination plate reduce 28.5% of its than inclination plate settler.

• The korean journal of orthodontics
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• v.28 no.4 s.69
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• pp.601-609
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• 1998

The objects of this study were to analyze the crown angulation, crown inclination, molar offset angle, and crown in and out of the Korean adults having normal occlusion. 14 subjects (7 male, 7 female) were chosen in the 80 subjects who had ideal occlusion and beautiful profile we thought. The casts were obtained from the subjects, and then they were scanned with 3-dimensional scanner machine. We analyzed them with computer program based upon Andrews methods and the following results were obtained. 1. We got the norm of the crown angulation, crown inclination, molar offset angle, and crown in and out in the Korean adults. 2. The analysis using 3 dimensional scanner and computer program was more fast and accurate than the manual methods.

• Journal of computational fluids engineering
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• v.14 no.2
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• pp.52-58
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• 2009

Turbulent flow past an inclined square cylinder immersed in a cross stream is numerically investigated. The angle of incidence of main flow is one of the key factors determining at which edges the flow separates. In the present study, based on comprehensive numerical simulations, effects of inclination angle on the flow characteristics are elucidated and the related physical explanation is presented.

• KIEAE Journal
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• v.14 no.1
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• pp.67-74
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• 2014

There have distinctly been no the installation criteria and maintenance management of BIPV systems, although the BIPV market is consistently going on increasing. In addition, consideration of the BIPV generation quantity which has been installed at several diverse places is currently almost behind within region in Korea. Therefore, the main aim of this study is to evaluate the BIPV generation and to be base data of reducing rate depending on regional installation angles using PVpro which was verified by measured data. Various conditions were an angle of inclination and azimuth under six major cities: Seoul, Daejeon, Daegu, Busan, Gwangju, Jeju-si for the BIPV system generation analysis. As the results, Seoul showed the lowest BIPV generation: 1,054kWh/kWp.year, and Jeju-si have 5percent more generation: 1,108.0kWh/kWp.year than Seoul on horizontal plane. Gwangju and Daejeon turned out to have similar generation of result, and Busan showed the highest generation: 1,193.5kWh/kWp.year, which was increased by over 13percent from Seoul on horizontal plane. Another result, decreasing rate of BIPV generation depending on regional included angle indicate that the best position was located on azimuth: $0^{\circ}$(The south side) following the horizontal position(an angle of inclination: $30^{\circ}$). And the direction on a south vertical position(azimuth: $0^{\circ}$, an angle of inclination: $90^{\circ}$) then turned out reducing rate about 40percent compared with the best one. Therefore, these results would be used to identify the installation angle of the BIPV module as an appropriate position.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.4
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• pp.482-491
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• 2007

Statement of problem: The screws of dental implant, having various thread types, can be categorized into different classes by their geometrical form, and each type transmits dissimilar amount and form of stress to alveolar bone. Purpose: The purpose of this study was to find an inclination angle of the screw thread that is favorable in distributing the stresses to alveolar bone. Material and methods: In this study, We used three dimensional finite element analysis with modeling having three types of thread inclination angles and fixed pitch-0.8 mm (single thread type with $3.8^{\circ}$ inclination, double thread type with $7.7^{\circ}$ inclination, triple thread type with $11.5^{\circ}$ inclination). Results: The results obtained from this study were as follows; 1. When the number of thread increased, the amount of Von-Mises stress was reduced since the generated stress was effectively distributed. 2. Since the maximum principal stress affects on the alveolar bone can influence deeply on the longevity of the implants when comparing the magnitude of the maximum principal stress double thread had least amount of stress. This shows that the double thread screw gave best result. Conclusion: In conclusion, double, and triple thread screws were found to be more effective on distribution of the stress than the single thread screws. But, increasing in the thread inclination angle such as triple thread screw relate on the magnitude of the maximum principal stress affecting on the alveolar bone can become problematic. Thus, effective combination of thread number and thread inclination angle can help prolonging the longevity of implant.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.32-32
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• 2017

To increase rice production, manipulating plant architecture, especially developing new high-yielding cultivars with erect leaves, is crucial in rice breeding programs. Leaf inclination angle determines the light extinction coefficient (k) of the canopy. Erect leaves increase light penetration into the canopy and enable dense plantings with a high leaf area index, thus increasing biomass production and grain yield. Because of erect leaves, the high-yielding indica rice cultivar 'Takanari' has smaller k during ripening than 'Koshihikari', a japonica cultivar with good eating quality. In our previous study, using chromosome segment substitution lines (CSSLs) derived from a cross between 'Takanari' and 'Koshihikari', we detected seven quantitative trait loci (QTLs) for leaf inclination angle on chromosomes 1 (two QTLs), 2, 3, 4, 7, and 12. In this study, we developed a near-isogenic line (NIL-3) carrying a 'Takanari' allele for increased leaf inclination angle on chromosome 3 in the 'Koshihikari' genetic background. We compared k, dry matter production, and grain yield of NIL-3 with those of 'Koshihikari' in the field from 2013 to 2016. NIL-3 had higher inclination angles of the flag, second, and third leaves at full heading and 3 (- 4) weeks after full heading and smaller k of the canopy at the ripening stage. Biomass at full heading and leaf area index at full heading and at harvest did not significantly differ between NIL-3 and 'Koshihikari'. However, biomass at harvest was significantly greater in NIL-3 than in 'Koshihikari' due to a higher net assimilation rate at the ripening stage. The photosynthetic rates of the flag and third leaves did not differ between NIL-3 and Koshihikari at ripening. Grain yield was higher in NIL-3 than 'Koshihikari'. Higher panicle number per square meter in NIL-3 contributed to the higher grain yield of NIL-3. We conclude that the QTL on chromosome 3 increases dry matter and grain production in rice by increasing leaf inclination angle.

• Structural Engineering and Mechanics
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• v.50 no.6
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• pp.797-816
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• 2014

Cooling tower is analyzed as an assembly of layered nonlinear shell elements. Geometric representation of the shell is enabled through layered nonlinear shell elements to define the different layers of reinforcements and concrete by considering the material nonlinearity of each layer for the cooling tower shell. Modal analysis using Ritz vector analysis and nonlinear time history analysis by direct integration method have been carried out to study the effects of the inclination of the supporting columns of the cooling tower shell on its dynamic characteristics. The cooling tower is supported by I-type columns and ${\Lambda}$-type columns supports having the different inclination angles. Relevant comparisons of the dynamic response of the structural system at the base level (at the junction of the column and shell), throat level and at the top of the tower have been made. Dynamic response of the cooling tower is found to be significantly sensitive to the change of the inclination of the supporting columns. It is also found that the stiffness of the structure system increases with increase in inclination angle of the supporting columns, resulting in decrease of the period of the structural system. The participation of the stiffness of the tower in structural response of the cooling tower is fund to be dependent of the change in the inclination angle and even in the types of the supporting columns.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.572-578
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• 2001

This study is to research the heat transfer characteristics in copper-water heat pipes with screen wick, #100. Recently, the semiconductor capacity of an electronic unit has been larger, on the contrary, its size is smaller than before. As a result, a high-performance cooling system is needed. Experimental variables are inclination angle and temperature of cooling water. The distilled water was used for the working fluid. At a inclination angle ${-6}^{\circ}$, #100 2layer screen mesh is shown the best heat transfer performance.