• Title/Summary/Keyword: M&As

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The Effects of High Concentration of Ascorbic Acid on the Growth of 3T6 Fibroblasts (고 농도의 비타민 C 첨가가 3T6 섬유아세포의 증식에 미치는 영향)

  • 김미향
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.4
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    • pp.651-656
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    • 2001
  • Ascorbic acid(AsA) is unevenly distributed throughout all body cells and fluids. Multiactivities of AsA in many biological systems and in various scientific fields were reported. In this study we aimed to clarify the inhibitory action of high concentration of AsA on the cell growth in 3T6 fibroblasts. The cells wee exposed to AsA at various concentration. It showed that 3T6 fibroblasts wee dead by the medium which contained AsA at the concentration higher than 0.5 mM. AsA caused hydrogen peroxide ($H_2O$$_2$) generation in a concentration dependent manner. These results suggested that the $H_2O$$_2$ was formed in the medium by AsA and acted as a cytotoxic gent. Moreover, it is supposed that hydroxyl radical (.OH) induced from $H_2O$$_2$also acetd as actively cytotoxic agent. This lethal effect of AsA causing the cell death was inhibited by the addition of catalase in the medium. Therefore, addition of AsA at the normal concentrations stimulate cell growth, but excess concentrations of AsA induce cell death.

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A study on standards for college and university library building areas (대학도서관 시설기준에 관한 연구)

  • 손정표
    • Journal of Korean Library and Information Science Society
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    • v.23
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    • pp.363-404
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    • 1995
  • This study is to set up a model of minimum and optimum standards for college and university library building areas in Korea. The results of this study are summarized as follows: 1. minimum standards(proposal) At first, Areas needed by factors of space component are as follows: User space --- 0.45 $m^{2}$ per student. Collection space --- 0.0107 $m^{2}$ per volume Staff space --- 10.1 $m^{2}$ per person Space attached to user, collection and staff space --- 5% of the sum of user, collection and staff areas(0.041 $m^{2}$ per student). Nonassignable space --- 25% of the sum of user, collection and staff areas (0.21 $m^{2}$ per student). Next, the formula to calculate the total area of the college and university library building is as follows: N = 0.45T $m^{2}$(a) + 0.0107V $m^{2}$(b) + 10.1S $m^{2}$(c) + 0.05(a+b+c) $m^{2}$, NS = 0.25N $m^{2}$. 2. Optimum standards(proposal) At first, Areas needed by factors of space component are as follows: User spae --- 0.64 $m^{2}$) per student. Collection space --- 0.01 $m^{2}$ per volume Staff space --- 9.7 $m^{2}$ per person Space attached to user, collection and staff space --- 5% of the sum of user, collection and staff areas(0.073 $m^{2}$ per student). Nonassignable space --- 25% of the sum of user, collection and staff areas(0.38 $m^{2}$ per student). Next, the formula to calculate the total area of the college and university library building is as follows: N = 0.64T $m^{2}$(a) + 0.01V $m^{2}$(b) + 9.7S $m^{2}$(c) + 0.05(a+b+c) $m^{2}$, NS = 0.25N $m^{2}$.

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Evaluation of Reductive Effect of Exposure Dose by Using Air Gap Apron in Nuclear Medicine Related Work Environment (핵의학과 내 작업 환경에서 공기층 납치마의 피폭선량 감소 효과 평가)

  • Lee, Wang-Hui;Ahn, Sung-Min
    • The Journal of the Korea Contents Association
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    • v.14 no.12
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    • pp.845-853
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    • 2014
  • In this study, we measured the dose reaching the OSLD dosimeter by using the regular lead apron, and air gap apron through 3 experiments, and researched the reductive effect of air gap apron on exposure dose based on the 140 keV gamma ray radiating from $^{99m}technetium$, which is the most commonly used in nuclear medicine. As a result, when the gap between the dosimeter and 0.2mm lead plate is 0 Cm, the average value of 10 dosimeters was 0.515 mSv, and when the gap between the dosimeter and lead plate is 20 Cm, the average value of 10 dosimeters was 0.138 mSv, which shows reductive effect of dose as much as 0.388 mSv. When the gap between the dosimeter and 0.5mm lead plate is 0 Cm, the average value of 10 dosimeters was 0.296 mSv, and when the gap between the dosimeter and lead plate is 20 Cm, the average value of 10 dosimeters was 0.075 mSv, which shows reductive effect of dose as much as 0.221 mSv. As we check the cumulative dosage for 3 days, the lead apron without air layer shows average 0.239 mSv, and the air gap apron shows 0.176 mSv, which is actually reduced by 0.062 mSv. As we check the cumulative dosage for a month, the lead apron without air layer shows 0.59 mSv, and the air gap apron shows 0.54 mSv, which is reduced by 0.05 mSv.

The Task of the Fashion Designer in Different Types of Domestic Women's Apparel Brands - Focusing on the Fashion Merchandising Process -

  • Kwon, Hae-Sook;Lee, Eun-A
    • Journal of Fashion Business
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    • v.8 no.6
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    • pp.90-102
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    • 2004
  • The purpose of this research is to identify the phases of the fashion merchandising process and the range of the fashion designer's work as well as performing degree at each stage according to the brand types of domestic women's apparel. The preliminary research was conducted with the chief designers of five woman's apparel manufactures located in Seoul and the questionnaires were collected from 192 fashion designers. They were measured by the five point Likert-type scales. For a data analysis, the Pearson's Correlation, ANOVA, Sheffe Test, MANOVA were used with SPSS V. 11.0. The results are as follows; 1. The steps which fashion designers of domestic apparel brand take in fashion merchandising process have been identified in 7 stages- Environment Information, Target Market Planning, Design Planning, Design Development, Price Settlement, Presentation & Line Release, Production. 2. The task achievement level of fashion designers in fashion merchandising process differs in brand types as well as in fashion merchandising stages. In NB, the designer's work was conducted in order of Design Planning(M=4.58)$\to$Presentation & Line release(M=4.31)$\to$ Environment Information(M=3.83)$\to$Target Market Planning(M=3.13). In DB, in order of Price Settlement (M=4.80)$\to$Production(M=4.33)$\to$Design Development(M=4.27)$\to$Design Planning(M=3.77)$\to$Presentation & Line release(M=3.20)$\to$Environment Information (M2.70). In GB, in order of Production(M=4.38)$\to$Design Planning(M=4.22)$\to$Price Settlement(M4.16)$\to$Environment Information(M=3.83)$\to$Merchandising Target Market (M=3.72)$\to$Design Development(M=3.65). 3. Considering the other factors such as sales, the amount of owning shops, item amounts that are related to the company size, this study shows that only the brand type affects designer's task achievement.

Evaluation of Coagulation Characteristics of Fe(III) and Al(III) Coagulant using On-line Monitoring Technique (On-line 모니터링 기법을 이용한 Al염계와 Fe염계 응집제의 응집특성 평가)

  • Son, Hee-Jong;Yoom, Hoon-Sik;Kim, Sang-Goo;Seo, Chang-Dong;Hwang, Young-Do
    • Journal of Environmental Science International
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    • v.23 no.4
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    • pp.715-722
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    • 2014
  • Effects of coagulation types on flocculation were investigated by using a photometric dispersion analyzer (PDA) as an on-line monitoring technique in this study. Nakdong River water were used and alum and ferric chloride were used as coagulants. The aim of this study is to compare the coagulation characteristics of alum and ferric chloride by a photometric dispersion analyzer (PDA). Floc growing rates ($R_v$) in three different water temperatures ($4^{\circ}C$, $16^{\circ}C$ and $30^{\circ}C$) and coagulants doses (0.15 mM, 0.20 mM and 0.25 mM as Al, Fe) were measured. The floc growing rate ($R_v$) by alum was 1.8~2.8 times higher than that of ferric chloride during rapid mixing period, however, for 0.15 mM~0.25 mM coagulant doses the floc growing rate ($R_v$) by ferric chloride was 1.1~2.3 times higher than that of alum in the slow mixing period at $16^{\circ}C$ water temperature. Reasonable coagulant doses of alum and ferric chloride for turbidity removal were 0.1 mM (as Al) and 0.2 mM (as Fe), respectively, and the removal efficiency of those coagulant doses showed 94% for alum and 97% for ferric chloride. The appropriate coagulant dose of alum and ferric chloride for removing dissolved organic carbon (DOC) showed about 0.3 mM (as Al, Fe) and at this dosage, DOC removal efficiencies were 36% and 44%, and ferric chloride was superior to the alum for removal of the DOC in water.

Bionomics of Tetranychus urticae Koch on Eggplants under Various Potassium Regimes in Controlled Environment (시설 재배 가지에서 칼리 시비 수준에 따른 점박이응애의 생물적 특성)

  • Kim, Ju;Lee, Sang-Koo;Kim, Jeong-Man;Kim, Tae-Heung;Lim, Ju-Rac;Chon, Hyoung-Gwon;Shin, Yong-Kyu
    • Korean journal of applied entomology
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    • v.47 no.3
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    • pp.217-226
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    • 2008
  • Development of T. urticae was studied on the leaves of eggplant grown in hydroponics with potash contents of 0 mM, 2 mM, 6 mM, and 12 mM. As the levels of potash increased, that of nitrogen decreased and that of P, K, Mg increased in the plant. While contents of crude protein and fiber decreased, those of ash and sugar increased. Carbohydrate content was the highest at 2 mM. Water contents increased as those of potash increased with the exception at 0 mM. Biomass was the heaviest as 552.7 g at 6 mM and the lightest at 0 mM. Leaf thickness and the content of chlorophyll increased as the content of potash increased. Laboratory leaf disc tests provided with various potash levels revealed that feeding and oviposition preferences of T. urticae were high at 6 mM and 12 mM, respectively. Ratio of damaged leaf by naturally occurring T. urticae on eggplants of 99 days post-transplant in the greenhouse was the highest at 6 mM. Development of immature stages of T. urticae shortened as the levels of potash increased with a less tendancy in male than in female. No differences were detected in adult longevity and oviposition period but the number of eggs laid was the most as 84.7 at 6 mM and the least as 40.6 at 0 mM. There were no differences in the rate of egg hatch and the ratio of sex. $R_o,\;r_m,\;and\;{\lambda}$ were the highest at 6 mM and the lowest at 0 mM. T and Dt were the lowest at 6 mM and the highest at 0 mM. There was a descending trand of T. urticae developmet when levels of potash either gets high or low in the hydroponics.

LOCATING ROOTS OF A CERTAIN CLASS OF POLYNOMIALS

  • Argyros, Ioannis K.;Hilout, Said
    • East Asian mathematical journal
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    • v.26 no.3
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    • pp.351-363
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    • 2010
  • We introduce a special class of real recurrent polynomials $f_m$$($m{\geq}1$) of degree m+1, with positive roots $s_m$, which are decreasing as m increases. The first root $s_1$, as well as the last one denoted by $s_{\infty}$ are expressed in closed form, and enclose all $s_m$ (m > 1). This technique is also used to find weaker than before [6] sufficient convergence conditions for some popular iterative processes converging to solutions of equations.

Estimating the mean number of objects in M/H2/1 model for web service

  • Lee, Yongjin
    • International journal of advanced smart convergence
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    • v.11 no.3
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    • pp.1-6
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    • 2022
  • In this paper, we estimate the mean number of objects in the M/H2/1 model for web service when the mean object size in the M/H2/1 model is equal to that of the M/G/1/PS and M/BP/1 models. To this end, we use the mean object size obtained by assuming that the mean latency of deterministic model is equal to that of M/H2/1, M/G/1/PS, and M/BP/1 models, respectively. Computational experiments show that if the shape parameter of the M/BP/1 model is 1.1 and the system load is greater than 0.35, the mean number of objects in the M/H2/1 model when mean object size of M/H2/1 model is the same as that of M/G/1/PS model is almost equal to the mean number of objects in the M/H2/1 model when the mean object size of M/H2/1 model is the same as that of M/BP/1 model. In addition, as the upper limit of the M/BP/1 model increases, the number of objects in the M/H2/1 model converges to one, which increases latency. These results mean that it is efficient to use small-sized objects in the web service environment.

RELATIVE AGE DIFFERENCE BETWEEN THE METAL-POOR GLOBULAR CLUSTERS M53 AND M92

  • CHO, DONG-HWAN;SUNG, HYUN-IL;LEE, SANG-GAK;YOON, TAE SEOG
    • Journal of The Korean Astronomical Society
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    • v.49 no.5
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    • pp.175-192
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    • 2016
  • CCD photometric observations of the globular cluster (GC), M53 (NGC 5024), are performed using the 1.8 m telescope at the Bohyunsan Optical Astronomy Observatory in Korea on the same nights (2002 April and 2003 May) as the observations of the GC M92 (NGC 6341) reported by Cho and Lee using the same instrumental setup. The data for M53 is reduced using the same method as used for M92 by Cho and Lee, including preprocessing, point-spread function fitting photometry, and standardization etc. Therefore, M53 and M92 are on the same photometric system defined by Landolt, and the photometry of M53 and M92 is tied together as closely as possible. After complete photometric reduction, the V versus B − V , V versus V − I, and V versus B − I color-magnitude diagrams (CMDs) of M53 are produced to derive the relative ages of M53 and M92 and derive the various characteristics of its CMDs in future analysis. From the present analysis, the relative ages of M53 and M92 are derived using the Δ(B − V ) method reported by VandenBerg et al. The relative age of M53 is found to be 1.6 ± 0.85 Gyr younger than that of M92 if the absolute age of M92 is taken to be 14 Gyr. This relative age difference between M53 and M92 causes slight differences in the horizontal-branch morphology of these two GCs.

Case Study on Decision-Making Process for M&A in Small and Medium Companies (중소기업 M&A 의사결정 과정에 관한 연구)

  • Jung, Han-Seok;Moon, Jae-Seung
    • Journal of Distribution Science
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    • v.13 no.10
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    • pp.65-72
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    • 2015
  • Purpose - A rapidly changing business environment places great demands on small and medium-sized enterprises (SMEs). These SMEs need to find strategic alternatives for continued growth and, ultimately, survival. Thus, mergers and acquisitions (M&A) are deemed an acceptable solution. Research to date has dealt with M&A in major organizations and focused on post merger integration (PMI). Our study focuses on SMEs, as they are relatively new and unknown to the public. Therefore, this study highlights successful M&A and decision making for SMEs through a case study analysis. Research design, data, and methodology - For this study, we examined an M&A case between company S, which produces cell phone parts, and company P, which produces SSD cases. We reviewed theories and previous studies in M&A literature. We comprehensively examined the decision-making procedure at each M&A stage, describing the situation of the buying company and the selling company from the period of the M&A announcement through deal completion. In addition, we conducted interviews with both companies. The data regarding this case study were collected through interviews with managers of both companies who actively participated in the M&A process. When necessary, we asked them about additional relevant information during the interviews. Results - The result of the M&A between company S and company P was deemed acceptable with the exception of the long negotiation period. However, company S was not able to prepare for PMI after the acquisition due to a controversy over acquisition values. Moreover, the employees of the newly formed company, especially those who came from company P, complained about the M&A and attempted to leave. Thus, implications for successful M&As of SMEs are as follows: First, the procedural compliance of the M&A is needed. Second, support is needed from the CEO for the working group, rather than excessive intervention during due diligence. Third, the right, talented members of the organization should be part of the process of the M&A. Fourth, the use of various types of outside expert or business consultants is needed. Fifth, the strategic intervention by Human Resource managers is required. Last, sharing M&A information among employees is important as information dissemination will help employees be more receptive to such a change. However, this study has several limitations as a single case study; more varied SME M&A case studies are needed in order to generalize the results of the study. Conclusions - Most of the research dealing with M&As has focused on major companies and PMI and neglected SMEs. Thus, our study focuses on SMEs and the decision-making procedures for M&A. This study has significantly contributed to the literature in this area and has provided practical information around the implications of sound decision-making during M&As. Specifically, the results of the study contribute to the need for research on M&A among SMEs, which to date has often been neglected as a topic of choice.