• Geomechanics and Engineering
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• v.1 no.3
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• pp.179-191
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• 2009

For a two-way drainage deposit under a surcharge load, it is possible to leave a layer adjacent to the bottom drainage boundary without prefabricated vertical drain (PVD) improvement and achieve approximately the same degree of consolidation as a fully penetrated case. This depth is designated as an optimum PVD installation depth. Further, for a two-way drainage deposit under vacuum pressure, if the PVDs are fully penetrated through the deposit, the vacuum pressure will leak through the bottom drainage boundary. In this case, the PVDs have to be partially penetrated, and there is an optimum installation depth. The equations for calculating these optimum installation depths are presented, and the usefulness of the equations is studied by using finite element analysis as well as laboratory model test results.

• Journal of Navigation and Port Research
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• v.43 no.5
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• pp.302-309
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• 2019

This study introduces the navigational environment database(DB) compiling water depth, sediment type and marine managed areas (MMAs) in coastal waters of South Korea. The water depth and sediment data were constructed by combining their sparse points of electronic navigation chart and survey data with high spatial resolution using the inverse distance weighting and natural neighbor interpolation method included in ArcGIS. The MMAs were integrated based on all shapefiles provided by several government agencies using ArcGIS because the areas should be used in an emergency case of ship. To test the validity of the constructed DB, we conducted a test application for grounding and anchoring zones using a ship accident case. The result revealed each area of possible grounding candidates and anchorages is calculated and displayed properly, excluding obstacle places.

• Journal of Multimedia Information System
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• v.4 no.1
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• pp.43-50
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• 2017

In this paper, we propose a method which detects the nose and face of certain human by using the depth image. The proposed method has advantages of the low computational complexity and the high accuracy even in dark environment. Also, the detection accuracy of nose and face does not change in various postures. The proposed method first locates the locally protruding part from the depth image of the human body captured through the depth camera, and then confirms the nose through the depth characteristic of the nose and surrounding pixels. After finding the correct pixel of the nose, we determine the region of interest centered on the nose. In this case, the size of the region of interest is variable depending on the depth value of the nose. Then, face region can be found by performing binarization using the depth histogram in the region of interest. The proposed method can detect the nose and the face accurately regardless of the pose or the illumination of the captured area.

• The Research Journal of the Costume Culture
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• v.5 no.4
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• pp.112-129
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• 1997

This research, focused on the curved of the lower body, designated abdomen and hip gradient, crotch depth and crotch width the factors for which are able to influence on the appearence and the function of Divided Skirt and analized the changes when that were applied to a real pattern, and so the purpose of this research is to show the basic documents needed to design a Divided Skirt pattern fitting with the wear purpose and usage. The following are the results of this research. 1. The abdomen and hip gradient turned out as the most influential factor on the appearance and the function of Divided Skirt. The pattern of which the abdomen and hip gradient was designated as vertical zero degree, showed an excellent appearance and in case of function, the pattern of which thw angle of the abdomen and hip gradient of human body type was applied to itself without a particular designation turned out excellent. 2. In case of crotch depth, the pattern which had crotch depth＋2㎝, had a better appearance but influced nothing on function. 3. The factor of crotch width didn\`t have any influence on the appearance and function of Divided Skirt. 4. Referring to the results of the above, the Divided Skirt pattern of which the appearance and the function turned excellent, had the angle of abdomen gradient 4 degrees, the angle abdomen gradient 4 degrees, the angle of hip gradient/2+2.5 degrees, crotch depth+2㎝ and crotch width following human body type. In case of Divied Skirt worn when going out, the pattern which had the angle of abdomen and hip gradient vertical zero degree, crotch depth+2㎝ and crotch width following human body type, turned out suitable. Also, the suitable pattern of Divided Skirt for working had the abdomen and hip gradient following human body type, crotch depth+2㎝ and covering girth diameter/2±1㎝.

• Journal of Korea Water Resources Association
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• v.34 no.6
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• pp.641-649
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• 2001

This study analyzed the general scour characteristics around group pile foundations through laboratory experiments. The experiments were performed for the pile groups consisting of 4, 9, 15 and 35 piles to investigate the effects of pile number, mean velocity and the angle of attack on the scour hole shape, and the magnitude and the position of maximum scour depth. Results reveal that the maximum scour depth for 4 and 9 piles have almost same values with single pier case regardless of approach velocity. The scour depth for 15 and 35 piles, however, increases as the mean velocity increases and reaches up to 2.2 times of maximum scour depth for single pier case. As the number of piles increase, the single scour holes are superposed and the overall scour hole turned out to be rectangular shape. The experimental results for the case of 35 piles indicate that the scour depth has the maximum value at angle of attack of 35 degree and that the main scour hole is formed in diagonal direction.

• Bulletin of the Society of Naval Architects of Korea
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• v.12 no.2
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• pp.59-66
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• 1975

Recently, as the dimensions of energy carriers increase, especially in draft, a reliable prediction of the ship motions at finite depths of water becomes necessary. The purpose of this paper is to probe the effect of finite water depth on the hydrodynamic forces and ship motions, particularly heave and pitch, in longitudinal regular head waves, by comparing the experimental value of Freakes and Keay with the author's theoretical value obtained by applying the modified strip theory to the Mariner class ship. It is confirmed that generally the hydrodynamic coefficients in the equations of motion increase with decreasing water depth, and the wave exciting forces and moments decrease with decreasing water depth. Amplitudes of heave and pitch in longitudinal regular head waves decrease as the water depth in the range where the length of the incident wave is comparatively long. The effects of Froude Number on the hydrodynamic coefficients increase with decreasing water depth and is more noticeable in the case of heave than pitch. In heave, generally the discrepancy between the experimental value and the theoretical value is relatively small in the case of $F_n=O$, but it is very large in the case of $F_n=0.2$. It is considered that the trend stems from the ignorance of the three dimensional effect and the other effects due to shallowness of water on the hydrodynamic coefficients in the theoretical calculation. An extension of methods for calculating the two dimensional hydrodynamic forces to included the effect of forward speed should be recommended. It is required that more experimental works in finite water depths will be carried out for correlation studies between the theoretical calculation, according tp modified strip theory, and model experiments.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.3
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• pp.173-182
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• 2011

The purpose of this paper is to provide useful information for fishermen in the manner of investigation a sinking speed of current type tuna longline gear at the North Pacific Ocean as a new developed tuna longline fishing ground. The sinking depth of mainline in connection with different basket was investigated. The experiments were also performed with different materials such as Supermansen (i.e., PE) and Hitech (i.e., PA) for the mainline to investigate the sinking depth of mainline and hooks. Furthermore, the relation between the sinking depth of hooks and catches are investigated also. The sinking depth of mainline at the first and the last shooting basket shows deeper than that of middle part of a basket due to reduced shortening ratio. The sinking depth of mainline and hook with Hitech material shows more shallow than that of Supermanse material, even the Hitech case was designed to sink deeper than that of Supermanse case. The highest catches arise at the middle part basket as the hook number 7 with around 248m sinking depth. From the results, longline with Hitech material is needed to increase the sinking force for reaching the relevant sinking depth. Moreover, the current strength at the North Pacific Ocean will be considered for further commercial fishing.

• Journal of Industrial Technology
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• v.32 no.A
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• pp.47-55
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• 2012

Currently, we only estimate the average flood water level by the cross-sections of the river using one-dimensional numerical analysis when establishing the basic plans. However, the reliability decreases when it comes to the river bend. In river bend, the difference of water-level between the inside and the outside of the river arises by centrifugal force. And it is estimated less than what it could be estimated when establishing the plan with average estimate of flood level. It is apprehended that the exterior of the river will be under-constructed when establishing the scour depth only with the mean depth. In the case of local scour of the abutment, it is difficult to estimate its depth precisely, and it tends to be over-estimated in the case of the empirical formulas. Therefore, the modification considering the deviation of the water depth of the exterior of the river bend is needed. In observing the deviation of each formula in river bend, it is found: Andru's formula for 58%, followed by the Laursen's for 26%, and the C.S.U's for 17% in pier, while it is 44% for Froehlich's formula in abutment. Under the 500CMS of the flood discharge, the deviation of the scour depth between pier and abutment was about 10 %. However, in further flood discharge, it shows 24~58% the biggest in deviation of piers. It is concluded that the scour depth estimate should be done with 2-dimensional numerical analysis.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.911-913
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• 1999

Shallow Trench Isolation (STI) has become the most promising isolation scheme for ULSI applications. The stress of STI structure is one of several factors to degrade characteristics of a device. The stress contours or STI structure vary with the trench depth. Isolation characteristics of STI was analyzed as the depth of trench varied. And transistor characteristics was compared. Isolation punch-through voltage for n$^{＋}$ to pwell and p$^{＋}$ to nwell increased as trench depth increased. n$^{＋}$ to pwell leakage current had nothing to do with trench depth but n$^{＋}$ to pwell leakage current decreased as trench depth increased. In the case of transistor characteristics, short channel effect was independent on trench depth and inverse narrow width effect was greater for deeper trenches. Therefore in order to achieve stable device, it is important to minimize stress by optimizing trench depth.

• Journal of the Korean Society for Railway
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• v.19 no.4
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• pp.506-514
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• 2016

Experimental ballast track and concrete track were installed on the railway site and the frost penetration depth and the frost heave amount in the winter were measured. As a result, when the freezing index was the same, the frost penetration depth of concrete track was deeper than that of ballast track. Furthermore, when an XPS and polyethylene aggregate layer was installed below the ballast track, the frost penetration depth of the ballast track decreased significantly; in the case of the concrete track, the frost penetration depth decreased when the thickness of the subbase increased. Meanwhile, the frost heave amount also decreased when an XPS and polyethylene aggregate layer was installed below the ballast track ; in the case of the concrete track, the frost heave amount decreased when the thickness of the subbase increased.