• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.2
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• pp.72-81
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• 2015

This paper studied the differences of the inventories asset turnover change ratio and several characteristics variable between large and small manufacturing firm group. Large and small firm group were determined based on number of labors and asset size. Several characteristics variable of firms such as assets size, sales growth rate, return on assets, leverage ratio, credit rating and age of firm were used to find out the differences of firm group. As a result, the inventory asset turnover change ratio of large firm was 5.16% and that of the middle and small firm was 9.3%. For the large firm, sales growth rate, ROA and credit rating affect inventory assets turnover change ratio. For the middle and small sized firm, Assets size, sales growth rate and credit rating affect inventory assets turnover change ratio. Using this result, we can say that manufacturing company need to consider their firm size and their characteristics to make their own operation strategy of inventory.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.530-533
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• 2006

Recently, a basic access method about IEEE 802.11 MAC layer protocol using IEEE 802.11 wireless LANs is the DCF thatis based on the CSMA/CA. But, cause of IEEE 802.11 MAC layer uses original backoff algorithm (exponential backoff method), when collision occurred, the size of contention windows increases the double size. Also, a time of packet transmission delay increases and efficiency is decreased by original backoff scheme. In this paper, we have analyzed TCP packet transmission time of IEEE 802.11 MAC DCF protocol for wireless LANs a proposed enhanced backoff algorithm. It is considered the transmission time of transmission control protocol (TCP) packet on the orthogonal frequency division multiplexing (OFDM) in additive white gaussian noise (AWGN) and Rician fading channel. From the results, a proposed enhanced backoff algorithm produces a better performance improvement than an original backoff in wireless LAN environment. Also, in OFDM/quadrature phase shift keying channel (QPSK), we can achieve that the transmission time in wireless channel decreases as the TCP packet size increases and based on the data collected, we can infer the correlation between packet size and the transmission time, allowing for an inference of the optimal packet size in the TCP layer.

• Korean Journal of Metals and Materials
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• v.46 no.1
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• pp.44-51
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• 2008

The effects of magnetic powder size on electromagnetic wave absorption characteristics in Fe-6.5Si-0.9Cr(wt%) alloy flakes/polymer composite sheets available for quasi-microwave band have been investigated. The composite sheet including small magnetic flakes with the size less than $26{\mu}m$ exhibited high power loss in the GHz frequency range as compared with the sheets having large alloy flakes of $45{\sim}75{\mu}m$. Moreover, both the complex permeability and the loss factor increased with the decrease in size of the alloy flakes. The large power loss of the sheets containing small magnetic flakes was attributed to the high complex permeability, especially their imaginary part. The high complex permeability of the sheets composed of small flakes was considered to be due to the highly thin shape of the flakes inducing low eddy-current loss.

• Asia Marketing Journal
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• v.21 no.1
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• pp.45-64
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• 2019

A great deal of research has explored individuals' attempts to simplify choices by constructing a consideration set. This research aims to investigate which construction strategy, either inclusion or exclusion, is more likely to be adopted and how the adoption of a particular construction strategy can affect consideration set size while identifying the moderating role of chronic indecisiveness in the construction process. The findings of Study 1 indicate that individuals are more likely to adopt an inclusion strategy to reduce a consideration set to a more manageable size, and that an exclusion strategy results in a larger consideration set. In Study 2, the findings reveal that high-indecisiveness individuals are less likely than low-indecisiveness individuals to select an inclusion strategy, but that high-indecisiveness individuals adopting an inclusion strategy are able to reduce the number of alternatives in a consideration set to a manageable size on par with the size of a consideration set formed by low-indecisiveness individuals without elevating the level of perceived difficulty. The current research contributes to the stream of research on consideration set construction and indecisiveness, and offers useful practical implications for overcoming indecisiveness. Limitations and avenues for further research are also discussed.

• Journal of Korean Home Economics Education Association
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• v.18 no.1 s.39
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• pp.113-125
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• 2006

The purpose of this study was to examine the effects of perception of body size on actual clothing style in middle school girls. To achieve this, this study analyzed self-perception of body size, aspired clothing style, and actual clothing style. By classifying groups into thin and thick, the difference in clothing style according to groups was also analyzed. Subjects of this study were middle school girls in Gwangju and 219 responses were collected from real body measurement and questionnaires. WIN SPSS+10.0 package was used to obtain results. Results are as follows: 1. For the self-perception of body size, middle school girls perceived much thicker in the lower body than the upper body. And they were unsatisfactory about the lower body which was perceived thick. 2. In the correlation of actual and aspired clothing style of middle school girls, they wore a aspired clothing style actually. Their actual or aspired upper clothing style was to cover the skin, exposing or covering a body silhouette. Their lower clothing style was a slacks type that covers a body silhouette and the skin. 3. In selecting actual clothing styles, middle school girls were somewhat affected by self-perceived body size. But they did not prefer the clothing styles perceived thick in girth or big in width in exposing the skin or a body silhouette. On the other hand, as it was perceived long, wearing was increased. frequently wore the upper and lower clothing styles of exposing the skin or a body silhouette than the thick group. But both groups wore the clothing styles of covering the skin or a body silhouette regardless of their thinness and thickness. And when wearing the clothing style of exposing neck and shoulder, middle school girls considered actual body size more than self-perceived size. On the other hand, when wearing the clothing style of exposing arms and silhouette by fitted legs, they considered self-perceived body size more.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.1
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• pp.119-130
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• 2004

The objective of this study was to develop a school uniform sizing system with high coverage rate for middle school boys, who are in the stage of rapid growth, by identifying problems in existing school uniform sizing systems through surveys of students and uniform manufacturing companies, and analyzing juveniles' physical sizes. For this purpose. the study conducted a survey about how middle school boys choose their uniform sizes, and what complaints they have on the size of the uniforms. In addition, it was investigated what is the current state of uniform manufacturing and sizing systems through a survey of uniform companies, and the study identified problems in the size of school uniforms by comparing physical sizes of juveniles' aged 14 to 16 with the sizing systems of the companies and KS standards in 1997. Juveniles' physical data was a part of the material of the national anthropometric data in 1997. Using the two-way distribution of juveniles' height-bust girth and height-waist girth, this study established the sizing system by increasing the number of sizes for the short interval where juveniles' physical sizes are densely distributed whereas limiting the number of sizes for the long interval where juveniles' physical sizes are rarely distributed, considering the difference between companies' standard and KS' standard.

• Imaging Science in Dentistry
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• v.43 no.2
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• pp.91-98
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• 2013

Purpose: This study was performed to identify correlations between keratocystic odontogenic tumor (KCOT) data from CT sections, and data on the KCOT clinical manifestation and resulting dental expenses. Materials and Methods: Following local Institutional Review Board (IRB) approval, a seven-years of retrospective study was performed regarding patients with KCOTs treated at the Seoul National University Dental Hospital. A total of 180 KCOT were included in this study. The following information was collected: age, gender, location and size of the lesion, radiological features, surgical treatment provided and dental expenses. Results: There was no significant association between the size of the KCOT and age, gender, and presenting preoperative symptoms. In both jaws, it was unusual to find KCOTs under 10 mm. The correlation between the number of teeth removed and the size of the KCOT in the tooth bearing area was statistically significant in the mandible, whereas in the maxilla, no significant relationship was found. Dental expenses compared with the size of the KCOT were found to be significant in both jaws. Conclusion: The size of KCOT was associated with a significant increase in dental expenses for both jaws and the number of teeth removed from the mandible. These findings emphasize the importance of routine examinations and early detection of lesions, which in turn helps preserving anatomical structures and reducing dental expenses.

• Korean Journal of Child Education & Care
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• v.19 no.3
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• pp.1-12
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• 2019

Objective: This study aims to thoroughly analyze the correlation effect size between domestic violence and school violence by meta-analyzing previous studies on the correlation between school and domestic violence. Methods: For this purpose, meta-analysis was performed on the selected research material, which consists of national research data collected from various databases from 2001 to April, 2019. 16 thesis and 9 papers on the correlation between school and domestic violence were selected. A random effect model analysis based on the homogeneity examination results was performed on the selected data. Results: The results showed, just as Cohen (1977) proposed, that the correlation effect size between domestic and school violence was 0.25, which is moderate. This is a somewhat lower number than the previous studies on the same subject presented. Of the sub-categories of domestic violence, physical violence and psychological violence appeared to have a correlation effect size of 0.34 and 0.28, respectively, with physical violence showing the highest correlation effect size. Of the types of domestic violence, witnessing spouse violence and experiencing neglect appeared to have a moderate correlation size effect of 0.24. All of these results were statistically significant. Conclusion/Implications: This study utilized meta-analysis as a comprehensive and systematic method to analyze the correlation effect between domestic and school violence. The results presented may lead to discussions on the subject's social implications, limits, and propositions for future studies.

• Journal of the Korean institute of surface engineering
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• v.56 no.3
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• pp.192-200
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• 2023

Graphene, a two-dimensional material, has shown great potential in a variety of applications including microelectronics, optoelectronics, and graphene-based batteries due to its excellent electronic conductivity. However, the production of large-area, high-quality graphene remains a challenge. In this study, we investigated graphene growth on electrolytic copper foil using thermochemical vapor deposition (TCVD) to achieve a similar level of quality to the cold-rolled copper substrate at a lower cost. The combined effects of pre-annealing time, graphenized temperature, and partial pressure of hydrogen on graphene coverage and domain size were analyzed and correlated with the roughness and crystallographic texture of the copper substrate. Our results show that controlling the crystallographic texture of copper substrates through annealing is an effective way to improve graphene growth properties, which will potentially lead to more efficient and cost-effective graphene production. At a hydrogen partial pressure that is disadvantageous in graphene growth, electrolytic copper had an average size of 8.039 ㎛², whereas rolled copper had a size of 19.092 ㎛², which was a large difference of 42.1% compared to rolled copper. However, at the proper hydrogen partial pressure, electrolytic copper had an average size of 30.279 ㎛² and rolled copper had a size of 32.378 ㎛², showing a much smaller difference of 93.5% than before. This observation suggests this potentially leads the way for more efficient and cost-effective graphene production.

• Journal of Korean Society of Forest Science
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• v.96 no.2
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• pp.227-234
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• 2007

The forest canopy gap has been well known as a substantial process of forest cyclic regeneration and important role in stand structure, dynamics, and biodiversity of the forest ecosystem. Based on 3,600 $5m{\times}5m$ square grids in a 9ha permanent experimental plot, the study was conducted to evaluate the regeneration pattern of woody species by developmental stage {seedlings (<1 m of height), saplingI (>1 m of height, <2 cm of DBH), and saplingII (2 cm$<200m^2$), $201-400m^2$, $400-600m^2$, $601-800m^2$, and $>800m^2$) in the mixed broadleaved-Korean pine forest. The results indicated that the regenerating trees of Populus ussuriensis occurred only in the canopy gap area, considered to be a typical gap-dependent species. The regeneration of Ulmus japonica, Ulmus laciniata, and Maackia amurensis could be generally satisfied with the gap size of $201-600m^2$, Betula costata and Prunus padus with gap size of $401-800m^2$, Picea koraiensis with gap size of $201-800m^2$, Fraxinus mandshurica and Syringa reticulata var. mandshurica with smaller than $800m^2$, respectively. Acer ukurunduense and Acer tegmentosum were likely to have no problem with the gap size to make gap regeneration. Acer mono and Tilia amurensis looked more capable of regenerating in the closed canopy disregarding the upper crown condition. The regeneration of Pinus koraiensis and Abies nephrolepis had no trouble under the canopy condition in less than $800m^2$of gap size. The density of regenerating shrubs was rather high, especially under the closed canopy, considered to be associated with great amount of regeneration production in such shade tolerant species as Lonicera maackii, Corylus mandshurica, Euonymus pauciflorus, and Philadelphus schrenkii under the closed canopy. Pearson correlation coefficient was computed to compare the similarity among non-gap area and five gap size classes by developmental stages for trees and shrubs. The similarity coefficients among closed canopy and the gap size classes were mostly significantly correlated to each other with a few exceptions.