• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.10
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• pp.1531-1536
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• 2022

This paper considers a problem to find a set of intervals containing all the points for the given n points and m intervals on a line, This is a special case of the set cover problem, well known as an NP-hard problem. As optimization criteria of the problem, there are minimizing the number of intervals to cover the points, maximizing the number of points each of which is covered by exactly one interval, and so on. In this paper, the intervals have weights and the sum of weights of intervals to cover a point is defined as a membership of the point. We will study the problem to find an interval cover minimizing the maximum of memberships of points. Using the dynamic programming method, we provide an O(m²)-time algorithm to improve the time complexity O(nm log n) given in the previous work.

• Journal of the Korean Society of Clothing and Textiles
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• v.43 no.5
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• pp.768-777
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• 2019

This study established a lower garment sizing system for elderly men over 65 years of age based on 535 males selected from the 5th Korean Anthropometric survey. The results are as follows. Most elderly men body measurements were smaller for adult males (except for the waist area); however, abdominal obesity has changed to body type. The standard deviation was applied around the average values of waist circumference and hip circumference for the suggestion of a lower garment sizing system for elderly men. The interval between the designation was ${\pm}2.5cm$ with an average waist circumference of 86 cm and ${\pm}2cm$ with an average hip circumference of 92 cm. A total of 13 designation sections were established in consideration of the cover ratio and cover efficiency. The cover ratio in the 13 nominal sections was 77.2%. The segmental distribution rate presented in the results will also be useful for production planning in specific sizes and enable rational production.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.2
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• pp.123-130
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• 2020

The impact of urbanization on LST (Land Surface Temperature) and TN (Tropical Night) was observed with the analyses of land cover change and LST by associating with the frequency of TN during the period of 1996 to 2016. The analyses of land cover and LST was based on the images of Landast 5 and 8 for September in 1996, 2006, and 2016 at a 10 year interval. The hourly-collected atmospheric temperatures for the months of July and August during the period were collected from AWSs (Automatic Weather Stations) in Seoul for the frequency analysis of TN. The study area was categorized into five land cover classes: urban or built-up area, forest, mixed vegetation, bare soil and water. It was found that vegetation (-7.71%) and bare soil (-9.04%) decreased during the period while built-up (17.29%) area was expanded throughout the whole period (1996-2016), indicating gradual urbanization. The changes came along with the LST rise in the urban area of built-up and bare soil in Seoul. In addition, the frequency of TN has increased in 4.108% and 7.03% for July and August respectively between the two periods of the 10 year interval, 1996-2006 and 2006-2016. By comparing the increasing trends of land cover, LST, and TN, we found a high probability that the frequency of TN had a relationship with land cover changes by the urbanization process in the study area.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.2
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• pp.310-320
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• 2020

This study established a lower garment sizing system for abdominal obesity adult women aged 30-59 based on 277 females selected from the 7th Size Korean Anthropometric survey. The criteria for subjects in this study were over 25 kg/㎡ of the BMI, over 85 cm of waist, and over 0.8 waist hip ratio. The results are as follows. The lower body analysis of abdominal obesity adult women showed that average circumference items were larger than the ordinary size, and the average length items were smaller. The standard deviation was applied around the average values of waist circumference and hip circumference for the suggestion of a lower garment sizing system for abdominal obesity adult women. The interval between the designation was ±1.5 cm with a waist circumference of 100 cm and ±2.5 cm with an average hip circumference of 100 cm. We established 13 designation sections in consideration of the cover ratio and cover efficiency. The cover ratio in the 13 nominal sections was 71.5%. The segmental distribution rate presented in the results will also be useful for production planning in specific sizes that helped enable rational production.

• Journal of applied mathematics & informatics
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• v.28 no.1_2
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• pp.1-11
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• 2010

The conditional covering problem is an important variation of well studied set covering problem. In the set covering problem, the problem is to find a minimum cardinality vertex set which will cover all the given demand points. The conditional covering problem asks to find a minimum cardinality vertex set that will cover not only the given demand points but also one another. This problem is NP-complete for general graphs. In this paper, we present an efficient algorithm to solve the conditional covering problem on interval graphs with n vertices which runs in O(n)time.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1470-1472
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• 2003

Hyperion, as hyperspectral data, is carried on NASA’s EO-1 satellite, can be used in more subtle discrimination on forest cover, with 224 band in 360 ?2580 nm (10nm interval). In this study, Hyperion image is used to investigate the effects of topography on the classification of forest cover, and to assess whether the topographic correction improves the discrimination of species units for practical forest mapping. A publicly available Digital Elevation Model (DEM), at a scale of 1:25,000, is used to model the radiance variation on forest, considering MSR(Mean Spectral Ratio) on antithesis aspects. Hyperion, as hyperspectral data, is corrected on a pixel-by-pixel basis to normalize the scene to a uniform solar illumination and viewing geometry. As a result, the approach on topographic effect normalization in hyperspectral data can effectively reduce the variation in detected radiance due to changes in forest illumination, progress the classification of forest cover.

• Journal of the Korean Society of Costume
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• v.55 no.6 s.96
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• pp.24-37
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• 2005

This study was performed to get basic data for gloves size system and pattern planning suitable Korean hand shape. Data was collected through measuring hand size of man and woman from age 18 to 30 as subjects living in metropolitan area. by analysing the measured data, the difference in man and woman and the gloves size system was established. The results of study are as follows: 1. The Deviation of hand girths and hand lengths was larger than that of hand width in both man group and woman group. In all items. deviation in man was larger than woman. 2. In sex difference, there was difference between mall group and woman group in all items. In age difference, there was difference between mall group and woman group in mainly girth and the difference was bigger in group under 24 years old than in group over 24 years old. 3. The weight showed the highest $correlation(r{\geqq}0.8)$ with girths and high correlation with widths $(r{\geqq}0.7).$ The height showed the highest positive $correlation(r{\geqq}0.8)$ with and elbow length and high correlations with width and girths item. There were high positive correlation between vertical lengths in hand and between horizontal lengths but low correlation between vertical lengths and horizontal lengths. 4. The basic parts for gloves size system, hand lengths and hand girths were divided into 1cm interval. The results shouted that $91.0\%$ of man group were ranged from 18cm to 20cm section and $92.4\%$, of woman group were ranged from 16cm to 18cm section. 5. The interval which has the highest covet· rate was hand length 19cm and hand girth 20cm interval which covered $18.65\%$ of man group. The intervals which showed cover rate more than $5\%$ was total 7 and they covered $73.1\%$ of man group. The interval which has which has the highest cover rate was hand length 17cm and hand girth 17cm interval which covered $21.37\%$ of woman group. The intervals which showed cover rate more than $5\%$ was total 6 and they covered $72.5\%$ of total woman group.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.5
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• pp.84-90
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• 2018

When producing a plastic horn cover for an automobile, since the interval between the ribs on the inner surface is narrow, conventional cooling channels cannot be applied and cooling of the mold is difficult. For this reason, the molding operation cannot be completed within a set cycle time. In this study, a conformal cooling channel was applied on the mold to solve the cooling problem. Injection molding simulation was carried out to confirm the effectiveness of the conformal cooling channel. In the analysis results, the mold temperature at the rib section decreased by 33%, and the mold temperature also decreased by 31%. This reduction in temperature allowed for molding within a set cycle time and demonstrated the effectiveness of the conformal cooling channel.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.8
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• pp.867-876
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• 2011

This study investigates the image of casual shirts according to color combination, tone, and interval of checked pattern in tone-in-tone coloration. The experimental materials developed for this study were a set of stimulus and response scales. The stimuli were 24 color pictures, in which color combination (RY: Red+Yellow, BP: Blue+Purple), tone (light, dull, dark), and interval (0.5cm, 1.5cm, 3.5cm, and 5.5cm) were manipulated. The 7-point scale was used for evaluation of image. Data were obtained from 240 female college students living in Seoul, Gwangju, Jinju, and Changwon in April 2010. For data analysis, ANOVA and Duncan-test were used by using SPSS program. The results of this study are as follows. Image according to color combination, tone, and interval of checked pattern consisted of five dimensions of attractiveness, youth- activity, appeal, modesty, and freshness. The cover combination showed an independent effect on freshness. Tone showed an independent effect on attractiveness, youth-activity, appeal, and modesty. Interval showed an independent effect on appeal, modesty, and freshness. Interaction effects of color combination and tone on youth-activity and appeal were found. In addition, interaction effects of tone and interval on attractiveness, youth-activity, and freshness were also found.

• Journal of the Korean Home Economics Association
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• v.43 no.9 s.211
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• pp.175-191
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• 2005

This paper proposed a sizig system for men's jackets in order to improve the clothing fitness and rain the productivity. The sizing system was classified according to 3 age groups. Figure types were categorized by shoulder angle and body shape. The size interval of the basic dimensions was established at regular intervals centering around their means. Altogether, 15 size charts were developed based on the frequency distribution. Size designating measurements for jackets were height, chest girth and waist girth. Size intervals were 3cm for chest and waist girth, 5m for height, and 2cm for waist and hip girth. Considering the cover factor, charts with a limited number of sizes were suggested with necessary measurements for each figure type of each age group.