• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.139-144
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• 1991

Chip flow angle is one of the important factors to be determined for the scheme of Chip Control. Up to now, however, a dependable way to predict the chip flow angle in practical cutting has not been established satisfactorily. In this paper a rather simple theoretical prediction of chip flow angle is tried based on some already widely confirmed hypotheses. The developed equation of chip flow angle contains the parameters of depth of cut d, feed rate f, nose radius $r_{n}$ side cutting edge angle $C_{s}$, side rake angle .alpha.$_{s}$ and back rake angle .alpha.$_{b}$. Theoretical results of chip flow angle given by this study bas been shown in a good agreement with experimental ones.s.s.s.s.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3021-3026
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• 2007

In this paper, experimental data on flow pattern transition of inclination angles from 0-90 are presented. A test section is constructed 2 mm long and I.D 1inch using transparent material. The test section is supported by aluminum frame that can be placed with any arbitrary inclined angles. The air-water two-phase flow is observed at room temperature and atmospheric condition using both high speed camera and void impedance meter. The signal is sampled with sampling rate 1kHz and is analyzed under fully-developed condition. Based on experimental data, flow pattern maps are made for various inclination angles. As increasing the inclination angels from 0 to 90, the flow pattern transitions on the plane jg-jf are changed, such as stratified flow to plug flow or slug flow or plug flow to bubbly flow. The transition lines between pattern regimes are moved or sometimes disappeared due to its inclined angle.

• Journal of the Korean Wood Science and Technology
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• v.21 no.2
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• pp.15-22
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• 1993

This study was carried out to investigate the fracture criterion of glulam. The mixed mode fracture of glulam was investigated by means of single edge notched specimens with various crack inclination in the longitudinal-radial plane. While fracture of wood is not completely understood, the study on linear-elastic fracture mechanics is a rational and valuable tool for studying the strength behavior of glulam. The results are summarized as follows : 1. Glue line has no effect on fracture strength. 2. There is a definite interaction between fracture toughness $K_I$ and $K_{II}$ during the mixed mode fracture of glulam. Several criterions for mixed mode failure were compared. The criterion was expressed in the following form: $(\frac{K_I}{K_{IC}})^2+(\frac{K_{II}}{K_{IIC}})^2=1$ 3. As crack inclination increases, $K_{IC}$ value and $K_{IIC}$ value decreases. The equations relating crack angle to $K_{IC}$ and $K_{IIC}$, respectively, were obtained as follows; $K_{IC}$ = -77.42${\gamma}$+153.72 ($R^2$ = 0.78) $K_{IIC}$ = -9.17${\gamma}$+34.90 ($R^2$ = 0.48)

• Tunnel and Underground Space
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• v.12 no.4
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• pp.268-276
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• 2002

In this study, a 3D coordinate measurement system equipped with a laser displacement meter for digitizing rock joint surface was established and the digitized data were used to calculate several roughness parameters. The parameters used in this study were micro avenge inclination $angle(i_{ave})$, average slope of joint $asperity(SL_{ ave})$, root mean square of $i-angle(i_{rms})$, standard deviation of height(SDH), standard deviation of $i-angle(SD_i)$, roughness profile $index(R_P)$, and fractal dimension(D). The relationships between the roughness parameters based on the digitzation of the surface profile were analyzed. Since the measured value varied according to the degree of reflection and the variation of colors at the measuring point, rock joint surface was painted in white to minimize the influence of the surface conditions. The comparison of the measured values and roughness parameters before and after painting revealed the better consequence from measurement on the painted surfaces. Also, effect of measuring interval was studied. As measured interval was increased, roughness parameters were exponentially decreased. The incremental sequence of degree of decrease was $SDH\; i_{ave},\; i_{rms},\; SD_i,\;and\; R_ p-1$. As a result of comparison of parameters from pin-type measurement system and laser type measurement system, all value of parameters were higher when laser-type measurement system was used, except SDH.

• Journal of the Korean Institute of Navigation
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• v.11 no.2
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• pp.73-88
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• 1987

It is well known that the height of tank metacenter above the centroid of fluid in a tank is given by i/v where I is the inertia moment of free surface and v is the fluid volume. It is supposed in this formula that the inclination of ship is small and that the free surface of fluid do not touch the top and the bottom of tank. It the inclination of ship is large, the height of tank metacenter may be possibly greater than that given by i/v. The height of tank metacenter is smaller than i/v when the free surface of fluid touch the top or the bottom of tank. The reasonable method to calculate the height of tank metacenter is presented in this paper and prepared in FORTRAN program by FUNCTION EFFRES. The approximate formula was also developed and given by $g_m=(1+\frac{2}{1}tan^2\theta)[1-EXP\{-12(\frac{\alpha(1-\alpha)k}{tan\theta})^{1.25}\}]\frac{i}{v}$ where $g_m$ is the distance from the centroid of fluid to the tank metacenter, $\theta$ is inclined angle of ship, $\alpha$ is the ratio of filled volume to tank capacity and k is the ratio of the depth to the width of tank. The values calculated by the approximate formula given in this paper were compared with the exact values from the computer program and proved out to be sufficiently precise for practical use.

• Water Engineering Research
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• v.4 no.2
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• pp.87-97
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• 2003

In this study, using the numerical model, the flow motion around skewed abutment is investigated to evaluate the skewness effect on the flow distribution. The skewness angle of the abutment which make with main flow direction is changed from $30\circ$ to $150\circ$ with increments of $10\circ$ while the contraction ratios due to the abutment are kept constant. For the investigation of the combined effects on the relationship between the skewness angle and flow intensities, this process will be .repeated fer different types of abutment (single and double) with different flow intensities. The maximum velocities and the velocity distributions, which can be obtained from each angle, are examined and analyzed corresponding to different angles of inclination. Based on successive model applications, an empirical expression, given in a function of contracted ratio and skewness angle, is derived for relating velocity amplifications according to the angle variations.

• The korean journal of orthodontics
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• v.37 no.2 s.121
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• pp.114-124
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• 2007

Objective: The purpose of this study was to examine how the mesio-distal angulation and the length of each tooth changes on panoramic radiograph at different bucco-lingual inclinations. Methods: After constructing an acrylic model based on the mean arch of 30 adults with normal occlusion, the wire was placed in the center of the teeth on the acrylic model. First, the wire was implanted in normal angulation and inclination and a panoramic radiograph taken. After changing the inclination from $I-5^{\circ}\;to\;I+15^{\circ}\;by\;5^{\circ}$, a panoramic radiograph was taken again and the mesio-distal angle and wire length on the panoramic radiograph were assessed. Results: When the wire was implanted at the normal angulation and inclination, the length measured in the panoramic radiograph was magnified $111{\sim}117%$ from the original length in the anterior region and $121{\sim}125%$ in the posterior region. Only the central and lateral incisors showed significant length differences when the inclination was changed from $l-15^{\circ}\;to\;I+15^{\circ}$ at fixed angulation. When the inclination was changed from $l-15^{\circ}\;to\;I+15^{\circ}$, the angulation of most teeth on panoramic radiograph appeared to be more disto-angulated than in reality, and the lateral incisor and canine showed the largest difference. Only $l-15^{\circ}\;to\;I+15^{\circ}$ groups of premolars and $I+15^{\circ}$ group of molars showed more mesio-angulation than in reality. As the labio(bucco)lingual inclination of all teeth were decreased, tooth angulation in the panoramic radiograph appeared to be more disto-angulated. Conclusion: The labio-liugual inclination of teeth should be considered because it affects panoramic image of teeth, such as length of incisors and angulation of other teeth.

• Journal of the Korean Society for Precision Engineering
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• v.1 no.3
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• pp.95-105
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• 1984

The purpose of this paper is to predict the cutting force, utilizing new model of double cutting edge which has normal rake angle and tool inclination angle. Changing side, back rake angle and side cutting edge angle in the new model. Three dimensional cutting force was obtained by the use of .eta. /c=i proposed by Stabler and energy method for three dimen- sional cutting force. Theoretical results has been calculated with development of optimization algorism which can be put into three dimensional theory, using the method of least square with orthogonal cutting data. IT is proved that three dimensional cutting force is to be predicted accurately only if orthogonal cutting force by equalizing theoretical result and experimental result has been calculated.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.2
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• pp.137-146
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• 1998

The experimental study is concerned with two-phase closed thermosyphons, (i.e., wickless heat pipes) for the cooling of high power electronic components in telecommunication system. The thermosyphon which can deal with a high heat flux of up to $4.9W/cm^2$ is developed, and the cooling characteristics of thermosyphon is analyzed according to design parameters which are the types of and quantity of working fluid, number of pipes, wire insertion in pipe, inclination angle of thermosyphon, and cooling air velocity. Using water as working fluid is superior cooling performance compared to using acetone, and cooling performance is improved as the number of thermosyphon becomes larger, inserting wires in the pipes, and inclination of $30~60^{\circ}$.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.773-776
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• 2005

An Experiment was carried out to study deburring in frilling hole on the Inclined exit surface. Two different deburring tools, exit surface angles, materials and cutting conditions were selected to check their performance using CNC machining center. In deburring operation, there are not only flat exit surfaces but also inclined exit surfaces which is described as inclination angle. Inclination of exit surface causes a quite different burr formation when comparing with flat surface. Deburring characteristics are analyzed according to the deburring tools and cutting conditions. Several strategies for a effective deburring on inclined exit surface were proposed.