• Journal of the Society of Naval Architects of Korea
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• v.43 no.6 s.150
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• pp.647-655
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• 2006

In this paper, submerged body dynamics model in vertical plane which can include the effect of free surface and wave is suggested to simulate the motions of submerged body moving beneath free surface precisely. A controller is designed, which can maintain a constant depth below the mean sea level and minimize the pitch angle. Numerical simulations show that the designed controller is effective on depth keeping and minimizing pitch angle in regular waves and irregular waves.

• Journal of the Ergonomics Society of Korea
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• v.18 no.1
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• pp.41-53
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• 1999

The effect of menu width and depth on the efficiency of information search and menu preference was investigated to identify an optimal menu structure for EIG which reflects the characteristics of human information processing. Information search time increased stepwisely as the menu width exceeded 6 items and linearly as the level of menu depth increased. The linear relationship between the error rate and the number of depth levels seems to be caused by the increase in the items to be remembered. When a menu structure was constructed by combining different menu depths and widths, it was observed that making the menu width wider rather than the depth deeper allows better information search. The menu structure rated as the most preferable and the easiest to user was that of pyramidal form. Such a result seems to come from its structural similarity to general categories which people get used to and implies that one should consider user preference as well as efficiency of search when he/she designs an EIG menu.

• Journal of the Korean Home Economics Association
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• v.40 no.10
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• pp.113-121
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• 2002

The purpose of this study was to investigate the effect of the depth of fashion product line on sales. The depth of the fashion product line was defined as the variety of style, color, and size in the outwear line for this study. Data were collected from the 98 brands in 4 department stores located in Seoul and Pusan. The result showed the significant impact of the variety of the outwear style on sales. Even after controlling the effect of advertising and the level of price in each brand, significant effect of the variety of outwear style were noticed on sales.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.99-105
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• 2001

The purpose of this study is to investigate the effects of pending depth treatment on water balance in paddy fields. The pending depth treatments were very shallow, shallow and deep. The experimental plots were three $80m{\times}25m$ rectangular plots. Daily values of rainfall amount, pending depth, irrigation water, drainage water, evapotranspiration, infiltration, and piezometeric head were measured in the field. The pending depth was continuously observered by water level logger during the growing season. The ET was measured in 1m diameter PVC lysimeters. Irrigation water volume was measured by 75m pipe flow meter and the drainage water volume was measured by 25mm and 75mm pipe flow meters and a recording Parshall fulume. PVC pipe piezometers with 12mm diameter were used. The results of the water balance showed that irrigation water of 881.1mm, 735.4mm, and 532.6mm in very shallow, shallow, and deep pending, respectively. The effective rainfall was 182.6mm(44.6%), 254.7mm(62.2%), and 188.6mm(46.0%) in very shallow, shallow, and deep pending, respectively. The results show that the shallow pending depth looks the best of the three treatments.

• Journal of Broadcast Engineering
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• v.22 no.1
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• pp.42-50
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• 2017

A Bit-depth expansion is a method to increase the number of bit. It is getting important as the needs of HDR (High Dynamic Range) display or resolution of display have been increased because the level of luminance or expressiveness of color is proportional to the number of bit in the display. In this paper, we present effective bit-depth expansion algorithm for conventional standard 8 bit-depth content to display in high bit-depth device (10 bits). Proposed method shows better result comparing with recently developed methods in quantitative (PSNR) with low complexity. The proposed method shows 1db higher in PSNR measurement with 40 times faster in computational time.

• Journal of Korea Water Resources Association
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• v.31 no.2
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• pp.167-176
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• 1998

On steep hillslopes, saturation zone formations and subsurface flows were monitored through the observation systems of observation wells, tensiometers and trenches. By the 103 mm rain which had fallen on the hillslope with dry soil moisture, the saturation zone began to be formed at the top of hillslope during the rain and developed to be formed within a few hours after the end of rain on all hillslope. Subsurface water outflowed mainly from the soil profile of 0-40 cm depth, but did not outflow from the one of 40-80 cm depth. This saturation zone seemed to be formed by partially saturation of soil. This resulted for two reasons. Firstly, the saturation zone was formed by a smaller amount of rain than that required. Secondly the soil at a certain depth below the water table was unsaturated. Saturation zones formed by pre-rains responded rapidly to rains and subsurface water outflowed mainly from the soil profile of 40-80 cm depth simultaneously with the rising of the water level. The rates of subsurface discharge from the soil profile of 40-80 cm depth to the precipitation were related to the antecedent precipitation although the maximum water levels of saturation zone formed by four rains were similar.

• The Mathematical Education
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• v.60 no.3
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• pp.281-295
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• 2021

This study examines the breadth and depth of knowledge of the teacher employment test for secondary mathematics. For the breadth of knowledge, we attempted to figure out the range of knowledge in terms of the content areas using the standards from the Korea Society Educational Studies in Mathematics[KSESM](2008). For the depth of knowledge, we chose Anderson & Krathwohl(2001) framework to analyze levels of each item in the test. The results from the analysis of 180 items in the teacher employment test between 2014 and 2021 show that while items in mathematics education have considerable variation in terms of range and levels of knowledge, those in some subjects of mathematics can be found only certain level of knowledge. i.e., merely certain topics or levels of knowledge have been heavily evaluated. Thus, considering the breadth and depth of knowledge teachers should have, the current exam needs to be improved in terms of teacher knowledge. It does not mean that every topic and every level of knowledge should be evaluated. However, it is a meaningful opportunity to think about what kinds of knowledge teachers should have in relation to K-12 mathematics curriculum and how we can evaluate the knowledge. More collaborative effort is inevitable for the improvement of teacher knowledge and teacher employment test.

• Journal of Biosystems Engineering
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• v.29 no.3
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• pp.207-216
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• 2004

This study was intended to investigate the characteristics of ride vibrations transmitted to tractor operator during rotary tillage and plowing operations. Seat accelerations of a 41 ps diesel tractor in rotary tillage and plowing were measured and evaluated as specified in the ISO 2631-1. Effects of working speed and tilling depth on ride vibration were investigated. The level of ride vibration was also evaluated in terms of health guidance caution zones. Some of the results of the study are as follows: 1. The level of ride vibration in plowing was about 4.3 times greater than in rotary tillage. 2. The effect of working speed in rotary tillage differs depending upon the tillage depth. The level of ride vibration was increased with the speed, but it decreased over a certain tillage depth. Fore and aft vibration was 2.2-2.7 times severer than horizontal and vertical vibrations. Dominant frequency band was 1-3.15 ㎐ in fore and aft, 1-3.15㎐ and 16-25㎐ in horizontal, and 16-25㎐ in vertical directions. 3. Plowing reduced the ride vibration by 42.8-50.2%. But its positive effect decreased as the plowing speed increased. In plowing operation, ride vibration was similar degrees in fore and aft, horizontal and vertical directions. The dominant frequency band in plowing operation was 1-2.5㎐ in fore and aft, 1-2.5㎐ in horizontal, and 1-8㎐ in vertical directions. 4. On a basis of daily work hours of 4, total level of ride vibrations in plowing operation is likely to be harmful to operator's health.

• Korean Journal of Weed Science
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• v.11 no.2
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• pp.100-105
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• 1991

Maintaining the water level at 5cm depth showed less decreasing in number of tiller and dry weight as compared to 1 and 3cm depths when Bensulfuron and Pretilachlor were applied. The drainage more than 5cm as water level everyday caused the growth inhibition when Bensulfuron and Pretilachlor were used, while Dimepiperate was rather safe.

• Journal of the Korean housing association
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• v.22 no.3
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• pp.73-82
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• 2011

The purpose of this study was to develop the curriculum of spatial convergence studies for the major field of housing and interior design. Documentary research and content analysis methods were used in this study. Data drawn from internet homepage of each universities which were 20 colleges the major field of housing and interior design and 160 colleges of architectural design, and public institutions the MLTM and the KRIHS. The major results of this study were as follows. 1) Government has been supported the specialized graduate school of spatial information and the university which they have spatial information curriculum during 5 years. 2) The department of spatial information has been educated the theory and practice about spatial issues in order to train the spatial specialist helpful to the new growing industry. 3) There were little changed curriculum which has related to the department of housing and interior design. The half of their curriculum were housing project and interior design. The spatial convergence studies educational program should be grow up step by step. The first is basic level to learn the basic theory of spatial studies for example the spatial introduction or the housing and the second is low level to learn the depth theory of spatial studies for example the design I or the housing development. The third is middle level to apply the depth theory of spatial studies for examples the design II, III or housing policy and institutions. And the last is high level to practice the depth theory of spatial studies for example housing construction or internship.