• Korean Journal of Hydrosciences
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• v.5
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• pp.85-97
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• 1994

A hybrid finite difference method for the longitudinal dispersion equation, which is based on combining the Holly-Preissmann scheme with fifth-degree Hermite interpolating polynomial and the generalized Crank-Nicholson scheme, is described and comparatively evaluated with other characteristics-based numerical methods. Longitudinal dispersion of an instantaneously-loaded pollutant source is simulated, and computational results are compared with the exact solution. The present method is free from wiggles regardless of the Courant number, and exactly reproduces the location of the peak concentration. Overall accuracy of the computation increases for smaller value of the weighting factor, $\theta$of the model. Larger values of $\theta$ overestimates the peak concentration. Smaller Courant number yields better accuracy, in general, but the sensitivity is very low, especially when the value of $\theta$ is small. From comparisons with the hybrid method using cubic interpolating polynomial and with splitoperator methods, the present method shows the best performance in reproducing the exact solution as the advection becomes more dominant.

• Journal of Digital Convergence
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• v.12 no.7
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• pp.11-20
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• 2014

This paper finds that the ultimate source of problems facing Korean mobile telecommunications such as excessive subsidies of handsets, waste of resources, and a vicious circle of expensive handsets and high prices for services, is bundling of handset and subscription. The analysis suggests that bundling causes consumers to confuse about prices of handsets and services, and firms focus on handset subsidy competition rather than on upgrading service qualities and lowering prices due to anti-competitive effects of bundling. Because most of the cost of bundling is passed on to consumers, the welfare of consumers decline. In particular, equality among consumers worsens due to price discriminations. To resolve these problems, unbundling of handset and subscription is a necessity. Mixed bundling allowing separate selling of handsets under bundling does not seem to work as a cure because bundling tends to be a dominant strategy. The best regulatory policy is a complete separation of handset and subscription.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.3
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• pp.447-458
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• 1999

The purpose of this study was to analyze jeans market faced with economic difficulties to provide jean's maker with a large representative data base for jeans marketing strategy. This study surveyed jeans market and analyzed brand awareness. brand image and consumer's seeking image for 700 young adults. The 700 questionnaires were distributed at the five locations(Opkujung Shinchon Munjungdong, Shinrimdong '||'&'||' Suwon) and 656 reliable ones were used for statistical analysis. A. SAS statistical package including frequency table factor analysis. analysis of variance. and Duncan's multiple range test was used. The results are as follows : 1. Brand awareness involves "brand recall" based on asking a person to name recalled first and "brand rcognition" based on asking to identify brand name from 30 given brands. The result indicated that "Levis" was dominant for brand recall and Guess was dominant for brand recognition. 2. Regarding the brand image the result showed that "Vov" was best represented for sophisticated '||'&'||' trendy brand images "Storm" for characteristics brand image "Jambangee" for reasonable price '||'&'||' comfortable brand images and "Levis" for classic '||'&'||' design/color brand images. 3. As a result of factor analysis on consumer's seeking image six factors(characteristic/gay, intelligent/sexy, feminine/sophisticated , active/functional, cute/young, simple/comfortable) were found. Several factors had a relationship with demographic variables and preferred design. 4 Many young adults favored following design details ; low waist relaxed thigh with straight leg and long length up to the end of shoes. Also they preferred basic pocket to cargo pocket and simple logo accessories to metal ones.simple logo accessories to metal ones.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.4
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• pp.210-219
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• 2007

The benthic marine algal flora and community structure were examined at five sites of the Taean Peninsula, Korea, during July-August 2005. Ninety-six algal species were Identified, including 14 green, 21 brown, and 60 red algae, and 1 marine plant. The common species that occurred at the five sites were Sargassum thunbergii, Gelidium divaricatum, Caulacanthus okamurae, Gracilavia vermiculophylla, and Neorhodomela aculeata. Sthunbergii was the dominant species in terms of coverage and biomass at ail of the study sites. The average biomass varied from $23.72g/m^2$ in dry weight at Chaeseokpo to $66.43g/m^2$ at Padori. The species could be divided into six functional groups in terms of morphological characteristics: 41 coarsely branched forms, 25 filamentous forms, 16 sheet forms, 7 thick leathery forms, including the marine plant Phyllospadix iwatensis, 4 crustose forms, and 3 Jointed calcareous forms. The seaweed communities at the five study sites were unstable and the environmental conditions were bad or very bad. Among the five study sites, the ecological evaluation index (EEI) and diversity index (H') were maximal at Padori at 2.29 and 1.98, respectively. By contrast, the dominance index (DI) was minimal at Padori (0.55) and maximal at Baramarae (0.96). Therefore, we conclude that the rocky shore at Padori has the best environment among the five study sites, although the species richness and biomass of seaweeds have declined continuously over the last 10 years.

• The Journal of Information Systems
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• v.23 no.1
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• pp.225-246
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• 2014

With the recent establishment of a ubiquitous environment and the paradigm shift to a smart society, the use of mobile devices, such as smart phones and tablet PCs, has become widespread. Thus, the trend is gradually shifting from using Web-based Instant Messenger to using Mobile-based Instant Messenger. Mobile Instant Messenger refers to a service that allows instant messaging as well as data sending and receiving between individuals with exclusive application programs(mobile Apps), which can be used in portable devices-such as smart phones-with wireless Internet access. Korea's portal sites, telecommunication companies, and even big companies have all rushed into the MIM market to join the competition. The reason so many companies are showing interest in the MIM business is because it is rising as a core platform to substitute portal sites in the mobile society, and MIM is perceived as the best means to attract and secure users. The intention to reuse or use continually was considered an important factor in maintaining a dominant position amidst such fierce competition, and consequently, most research thus far has reflected such thought. However, the frequent or long-term use of a system alone cannot indicate the definite success of the system, nor guarantee its dominant position in the market. On the contrary, MIM dependence, which goes beyond simple repetitive use and indicates a state where users actually or emotionally depend on a specific system, can better explain the user action. However, not much research has been conducted on dependence. The research results showed that lively message, concise message, message responsiveness, and social belonging significantly affected perceived usefulness. Message responsiveness, Link, and social belonging significantly affected flow. Flow significantly affected MIM dependence, and perceived usefulness did not affect MIM dependence. This study has proven that lively message, concise message, message responsiveness, Link, social belonging and perceived usefulness are important antecedents and mediating factors of MIM dependence. Moreover, this study is significant in that it explains the overall process of MIM dependence, and expands on the variety and scope of research that can be applied to MIM-related studies.

• Journal of Korea Entertainment Industry Association
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• v.15 no.5
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• pp.33-43
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• 2021

Kakao M and Kakao page have been merged to form contents corporation, Kakao entertainment. Kakao M has 15 contents management agencies and 4 music labels, in addition to movie and drama productions. Kakao Page currently holds IP rights for about 8,500 content stories. This study explores the relationship between M&A for absorptive capacity and content value chain by considering the factors that determine boundary spanning behaviors. Using the Kakao entertainment in-depth case study as the practical lens, research results of this study are suggested. Kakao's effective M&A activities are critical key factor for absorptive capacity in the entertainment industry and has a strong network with advantage assets. Also, as the contents business becomes even more competitive, Kakao need to venture beyond entertainment boundaries to seize creative opportunities. Kakao entertainment with absorptive capacity and boundary spanning behaviors through M&A and contents value chain best qualified for entertainment dominant strategy.

• Journal of Korean society of Dental Hygiene
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• v.7 no.2
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• pp.197-211
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• 2007

The purpose of this study was to examine the image of dental hygienists. The subjects in the study were 396 patients and their caregivers who visited 14 dental hospitals and dentists' offices in and around Seoul. After a survey was conducted, the following findings were given: 1. The people investigated gave a mean of 4.0 to the image of dental hygienists. Dental hygienists rated highest in terms of looking neat and tidy(4.33), and were given the lowest marks in arbitrary job performance(3.46). 2. There appeared four different types of dental hygienist images, which made a 59.824 prediction of the image of dental hygienists in general. A typical image(4.11) was most dominant, followed by professional one(4.07), personal one(4.01) and social one(3.73). 3. The relations between the general characteristics of the respondents and their image of dental hygienists could be described as below: 1) By age, those who were in their 60s(4.12) had the best image of dental hygienists, and the teenagers(3.90) had the worst image of them. 2) By gender, the men(4.05) looked at dental hygienists more positively than the women(3.96). They had a significantly different opinion on the social image of dental hygienists according to gender(pE0.05). 3) By marital status, the married people(4.00) had a better image of dental hygienists than the unmarried ones(3.95). 4) As for the influence of the type of dental institutions, they had a more favorable image of dental hygienists in dentists' offices(4.13) than in dental hospitals(3.88). There was a broad significant difference in the way they looked at the professional and personal images of dental hygienists according to the type of dental institutions(pE0.001). 5) As to the impact of educational level, those who received community-college or higher education(4.01) had the best image of dental hygienists, and those who received middle-school or lower education(3.91) had the worst image of them. 6) By occupation, the government workers and students(4.07) had the best image of dental hygienists, and the company employees(3.90) had the worst image of them. They took a significantly different view of the social image of dental hygienists according to occupation(pE0.05). 7) Concerning the impact of the frequency of receiving dental treatment, the respondents who had received it seven times or more(4.16) had the best image of dental hygienists, and those who hadn't(3.79) the worst image of them. There was a wide significant gap according to that frequency. The way they looked at the typical, social and professional images of dental hygienists was quite different significantly according to that frequency as well(pE0.001). 8) As for the influence of whether they were accompanied by caregivers or not, the people who weren't accompanied by caregivers(3.99) had a better image of dental hygienists than those who were(3.97).

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.1
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• pp.72-79
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• 1999

The binder plays important roles in determining the quality of pigment coating. In addition to its primary role of binding the pigment to the base paper, the binder performs several other important functions. The binder, also referred to as the adhesive, is the dominant in the aqueous phase of the formulation. Thus it plays a major role in determining viscosity, rheology, water release, and setting time for the coating. Latices based on styrene-butadiene dominate the market for synthetic paper coating binders. Consumption is high and is expected to increase further due to the present tendeyncy toward high-solids coating. The purpose of this study is understanding the impact of various parameters of latex(i.e. Tg, Particle size) affecting prontabilities and optical properties of the coated papers, as well as providing basic information on the use of amphoteric latex for improving print qualities of coated papers. Recently, amphoteric latices, Which are cationic at low pH's but turn anionic at high pH's have attracted interests of paper scientists and engineers. Therefore we investigated the effect of the Tg(glass transition temperature) and particle size of amphoteric latex on the coating qualities. We also studied the effect of mixing ratios (Amphoteric / Anionic)of latex on the coating qualities. Our results showed that Tg and particle size of amphoteric latex have to be controlled for optimizing coated paper qualities. The formulation consisting of 10 parts of amphoteric latex and 5 parts of anionic latex gave best results in ink receptivity, smoothness, air permeability, opacity and sheet gloss. If the results hold for the industrial paper coatings, the amount of expensive amphoteric latex can be reduced while achieving best available printing quality.

• The Korean Journal of Malacology
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• v.32 no.3
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• pp.203-209
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• 2016

Growth and survival of the hard shelled mussel spat were investigated to confirm the possibe spat culture in seawater pond from September 2014 to April 2015. Also, we measured simultaneously environmental factors including water temperature, salinity, dissolved oxygen, pH, DIN, DIP, chlorophyll a, and abundance and dominant species of phytoplankton in seawater pond every month. Ranges of water temperature and salinity were $4.0-23.4^{\circ}C$ and 18.8-25.2 psu, respectively, which were rather lower than the reported optimal level. Monthly measured survival rates in all the spat cages were over 90%. Concentration of chlorophyll-a and abundance of phytoplankton were very high, and dominant species phytoplankton were cryptomonads and nanoflagellates. These dominant species were considered to be good food organisms for the bivalve spat. The experimental cage stocked 100 individuals per basket ($2,700ind.\;m^{-2}$) hanging in bottom of seawater pond revealed the highest growth in shell height ($7.63{\pm}4.65mm$), but all experimental cages stocked below 200 individuals per basket ($5,400ind.\;m^{-2}$) did not show statistically significant difference. We may expect that seawater pond would be one of the best culture ground for bivalve spats when appropriate measures are available.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.208-214
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• 1987

A genetic study on the panicle characters in Oryza sativa was carried out by means of a 5 x 5 diallel cross. The five parental varieties were Raekyung, Yeongnamjosaeng, Nongbaek, Yushin and Honenwase. All characters were correlated positively each other, except number of kernels per primary branch. The number of secondary branches per primary branch.was the most effective factor in determining the number of kernels per panicle, the next being the number of primary branches per panicle. Regression analyses of the data of Vr/Wr indicated the presence of non-allelic gene interactions for all characters. Overdominant characters were the number of kernels per panicle, the number of primary branches per panicle, the number of secondary branches per primary branch, the number of kernels per primary branch and sum of kernels on all the tertiary branches per panicle, suggesting that the characters were more influenced by dominant effect than additive effect. However, the number of kernels per secondary branch was partially dominant where the genetic variation was due more to additive effect than to dominance effect. But after omitting the parent which had non-allelic interaction gene, the characters; the number of kernels per panicle, the number of secondary branches per primary branch, and the number of kernels per secondary branch, were partially dominant. Narrow sense heritabilities(h$^2$ N) in number of kernels per panicle and number of secondary branches were high and moderate, respectively, but those of the rest were lower. Mean squares of GCA and SCA of all characters, except SCA of the number of kernels per secondary branch, were highly significant. Effects of GCA were larger than SCA effects in all characters. Raekyung, Yushin and Nongbaek had highly positive GCA, and the best positive SCA was observed in crosses of Nongbaek x Tongillines (Raekyung, Yushin, and Yeongnamjosaeng) in all characters.