• Korean Chemical Engineering Research
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• v.47 no.4
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• pp.481-487
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• 2009

In this of study, effects of input air velocity(0.05~0.22 m/sec) and molten carbonate salt temperature ($870{\sim}970^{\circ}C$) on flow regime transition have been studied by adopting a drift-flux model of air holdup and a stochastic analysis of differential pressure fluctuations in an air-molten sodium carbonate salt two-phase system(molten salt oxidation process). Air holdup where the flow regime transition begins was determined by air holdup-drift flux plot. The air holdup value which the flow regime transition begins was increased with increasing molten carbonate salt temperature due to the decrease of viscosity and surface tension of molten carbonate salt. To characterize the flow regime transition more quantitatively, differential pressure fluctuation signals have been analyzed by adopting the stochastic method such as phase space portraits and Kolmogorov entropy, The Kolmogorov entropy decreased with an increasing of molten carbonate salt temperature but increased gradually with an increase in an air velocity, however, it exhibited different tendency with the flow regime and the air velocity value which flow regime transition begins was same to the results of drift-flux analysis.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.1
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• pp.78-89
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• 1999

In this paper, to improve bandwidth amplitude fluctuation for the broadband signal in indoor propagation environment, we measured and analyzed broadband signal using a vertically polarized, horizontally polarized and circularly polarized antenna, conducting by frequency sweeping method in NLOS (Non-Line-of-Sight) environment. And, to investigate the optimum condition for the improvement of broadband propagation characteristics we also examined the effects of both human motions and transmission antenna height in the NLOS environment. As a result, in the case of NLOS environment, it was found that the amplitude deviation characteristics in frequency bandwidth can be improved by polarization diversity reception. Especially, we found that it is the best effective one to make polarization diversity reception branches, which install the circularly polarized antenna at transmitting end and install the polarized diversity branches received vertical or/and horizontal polarized wave at receiving end. The affection of a human motions is not so much in LOS and NLOS environment, but it can lead to the cause of burst error in indoor digital radio communications as the fade of signal strength become more deeper. And also, when raise the transmitting antenna up to the ceiling, the LOS and NLOS environment could be coexisted. In this case, it can be also inferred that frequency bandwidth amplitude deviation must be fundamentally improved by using polarization diversity reception technique to make the possibility of high transmission rate.

• Geophysics and Geophysical Exploration
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• v.21 no.1
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• pp.8-14
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• 2018

For the purpose of maintenance and prevention of earth fill dams against damage from natural hazards, automatic monitoring through various measuring instruments and resistivity survey has been carried out. Reservoirs and embankments have the structural vulnerability on the agricultural usages since most of them were built more than thirty years ago. The main aim to use monitoring method is to verify the safety and integrity of the dam. Resistivity survey can detect potential weaknesses, such as defective zones, anomalous seepages or internal erosion processes. Permanent resistivity monitoring systems were installed at a reservoir, which daily measurements have been taken every 6 hour. Using monitoring data for one year, anomalous seepage and structural defects were clarified for dam safety. Annual water level fluctuations are around 10 m. During their operation, reservoir dams are subject to a never-ending hydraulic load from the reservoir, which over the years may cause changes in the properties of the inner parts of the dam construction. Detailed analysis of the monitoring results was performed and showed that resistivities at most locations have been very stable over the full monitoring period excluding the effects of water fluctuation and seasons. To investigate the detectability of weak zone using the DC resistivity monitoring, numerical modeling with a simplified model for the drainage at a reservoir dam was also performed. The results showed that the seepage zone near drainage in a reservoir dam could be detected by resistivity response change.

• Journal of Labour Economics
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• v.26 no.2
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• pp.1-30
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• 2003

The recent experience about self-employment shows three main trends: first, its share out of the total workers has steadily increased, recording 37.6% in 2001, implying its prevalence and importance; second, its share out of male workers has caught up female workers', implying its importance to males as well as females; and finally, during the recent Economic Crisis when there was mass layoff and large scale bankruptcy, its share rapidly increased, reflecting its role of a buffer to economic fluctuation. However, there have been few studies on self-employment, mainly focusing on what makes someone choose it as an alternative to being employed. This study analyzes the determinants of the duration to terminate self-employment, by applying the proportional hazard model to the Korea Labor and Income Panel Survey(KLIPS) by the Korea Labor Institute. The KLIPS started the first wave in 1998 with the 5,000 household sample (and about 12,000 individual sample of household members aged 15 and more). In this study, the first four waves are used for analysis. The average duration of 5,357 spells of self-employment is 130 months. It shows slight difference between males(124 months) and females(138 months) while it widely ranges over industries (296 months for agriculture industry while 50 months for restaurant and hotel industry). Estimates of the proportional hazard model of the self-employment duration show that females are more likely to terminate self-employment while it is not statistically significant. The effect of age at starting self-employment on the hazard shows the inverse V-shape, which implies that, until a certain age(47 years), the hazard become higher as aging while, since then, it become lower as aging. The level of education has a positive effect on the hazard, implying that more education is related to the higher probability to be employed. The measures of economic performances, annual sales and earnings, are positively related to continuing self-employment while hardship at the start of self-employment measured by several ways has a negative effect. Training before opening business has a positive effect on keeping on self-employment and its effects are different over its providers, significantly positive for public providers while insignificant for private providers. More and further research on self-employment is urgent in the rapidly ageing society. To help workers to be self-employed, more public assistance is necessary for education, training, financing, marketing, management, and human resource management in order to make the olders consider self-employment as a good alternative rather than an inevitable one.

• Korean Journal of Adult Nursing
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• v.12 no.4
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• pp.690-705
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• 2000

This ethnography was based on Kleinman's explanatory model of a health care system. It is conducted to make thick discription of illness conception of the elderly in a sociocultural context. The basic assumptions were as follows. 1) A health care system is a cultural system, and as with any other cultural system, it is a system of symbolic meanings anchored in a particular arrangement of social institutions and patterns of interpersonal relationships; 2) In all societies health care activities are more or less interrelated. Therefore, they need to be in a holistic manner as socially organized responses to disease that constitute a special cultural system; health care system; 3) Health and illness experiences are the natural process of disease. Individuals who recognized a for state of health, their family, neighbors, and communities define the state, search for causes of the health problems, and response to it. According by, they proceed to search for healing stratagies. So, understanding of the illness experience is the starting point for health care. The study participants were 12 elders aged 60 or more. The fieldwork was conducted in an agricultural clan village of Namwon city. The data collection and analysis were cyclic, from descriptive observation, domain analysis, focused observation, taxanomic analysis, selected observation, componential analysis, and finally cultural themes were all analysed. Proxemic and text analysis techniques were used according to the characteristics of the data. The data of sociocultural context and descriptive data were collected from 1990 to 1992. Informations on illness concepts were collected during 1994 using focused observation. Data confirming and contrast observations were conducted from 1997 and 1999. Illness concepts of the elderly were taxonomized supernatural cause, non-supernatural cause, immediate cause, and ultimate cause. The supernatural ones were ancestors, god of home, god of village, and ghost such as 'sal(evil force of dead man)' and 'gagqui(ghost of begger)'. The non-supernatural ones were Ki, natural phenomenones, natural objects, foods, human and human behaviors. Immediate ones were insufficiency and overflows, discretion and consolidation, disorder and out of order, cloudness and contamination, and fluctuation and stagnation of supernatural cause and non-supernatural ones. Ultimate causes were intrusion and loss of supernatural and nonsupernatural ones. The cultural themes of illness concepts of the elderly are: 1) illness concepts are not based on causality principle, but on reciprocal principle; 2) illness concepts are affected by social level and charicteristics of the patients; 3) the causes of disease are recognized as imposed both positive and negative effects on health based on interpretation of the indiviuals; 4) illness concepts reflects on principles of everyday life of the society members such as hierachial structure and group cohesiveness; 5) illness concepts are ruled on principle of reciprocity and spread; 6) illness concepts are interrelated with physical environment of the participants. It can be concluded that the illness concepts of the elderly in a traditional clan village are a component of health care system as a cultural system based on these results. The these results can be a useful basis for gerontological nursing practice and education.

• Journal of Distribution Science
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• v.11 no.4
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• pp.81-88
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• 2013

Purpose - This paper analyzes the influence of the RMB internationalization on the KRW/dollar exchange rate using an autoregressive distributed lag model. Comparing the parameter estimators from the sample period before and after the global financial crisis, we found that the RMB/dollar exchange rate has increasingly become more influential on the KRW/dollar exchange rate. Moreover, for the past several years, the Chinese government has actively utilized the financial service FTA negotiation as a measure for the RMB internationalization. This paper simultaneously considers RMB internationalization and financial service negotiations in the Korean-Chinese FTA. The purpose of this paper is to explicitly suggest a direction for the financial service negotiations in the Korean-Chinese FTA considering the effects of RMB internationalization. Research design, data, and methodology - The research plan of this paper has two parts. First, for an empirical study, this paper uses the daily exchange rate of the U.S. dollar against the currencies of the ASEAN5, Taiwan,and Korea. By using an autoregressive distributed lag model, this paper studies the influence of the change in the RMB/dollar exchange rate on changes in the local currency/dollar exchange rate in seven economies neighboring China. Our sample periods are 06/2005 - 07/2008 and 06/2010 -02/2013. During these periods, China was under the multi-currency basket system. We exempted the period of 08/2008 - 05/2010 from the analysis because there was nearly no RMB/dollar exchange rate fluctuation during those months. Second, after analyzing the recent financial service liberalizations and deregulations in China, we recommend a direction for the financial service negotiations in the Korean-Chinese FTA. In the past several years,the main Chinese financial policy agenda has surrounded the RMB internationalization. Therefore, it is crucial to understand this in the search for strategies for the financial service negotiations in the Korean-Chinese FTA. This paper employs an existing literature survey and examines the FTA protocols in its research methodology. Results and Conclusions - After the global financial crisis, the Chinese government wanted to break away from the dollar influence and pursued independent RMB internationalization in order to continue the growth and stability of its economy. Hence, every neighboring economy of China has been strategically impacted by RMB internationalization. Nevertheless, there is little empirical study on the influence of RMB internationalization on the KRW/dollar exchange rate. This paper is one of the few studies to analyze this problem comprehensively. By using a relatively simple estimation model, we can confirm that the coefficient of the RMB/dollar exchange rate has become more significant, except in the case of Indonesia. Although Korea is not under the multi-currency basket system but under the weakly controlled floating exchange rate system, its coefficient appears as large as that of the ASEAN5. This is the basis of the currency cooperation that has grown from the expansion of trade between the two countries. These empirical results suggest that the Korean government should specifically consider the RMB internationalization in the Korean-Chinese FTA negotiations.

• Asia pacific journal of information systems
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• v.21 no.2
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• pp.59-87
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• 2011

These days, firms are focusing on the improvement of relationships with business partners. The supply chain integrations are taking critical role in improving the relationships with business partners. In accordance with the development of the IT technology, it became possible for firms not only to integrate inner parts of the organization, but also to integrate the company with other organizations in the supply chain. Therefore, in e-Biz environments, it is imperative for firms to strengthen the core capacity through the supply chain, and to precisely determine the components of the determinants of e-Business integration which impact the firm performance. This study analyzed determinants that have impacts on e-business integration in e-business capacity perspectives in competitive environments. This study based on the premise that the resources and capacities that Grant(1991) and Hart(1995) emphasized do not directly influence the corporate performance. This study focused on the fact that corporate must create core competencies based on these capacities to establish competitive edge. Therefore, this study model analyzed to find out which e-Biz competencies are needed to integrate e-Biz according to competitive environment elements. This study designed to empirically analyze the impact of the e-Biz competencies to the e-Biz integration and to the corporate performance. Independent variables of this study-IT management, partner management, e-Biz knowledge, e-Biz establishment and proliferation, process innovation-are selected based on precedent studies on e-Biz competencies. We selected intermediate variables to verify that e-Biz competencies do not have direct impact on the corporate performance, but have impact on the e-Biz integration, which is intermediate effect. That is to verify that if the components of supply chain improve the integration level using e-Biz competencies, the overall supply chain performances will improve. Dependent variables are selected to verify that e-Biz integration has impacts on corporate performances. This study used factor analysis, path analysis, moderating effect analysis as statistical tests. First, we used exploratory factor analysis and confirmatory factor analysis to analyze reliability and validity. Because e-Biz competencies are presented variously by preceding studies, we used SPSS16.0 to verify if survey questionnaire used by theoretical backgrounds is properly composed. Second, we tested the property of structure model by AMOS. We did path analysis using AMOS16.0 to test structure that is composed of e-Biz competencies and e-Biz integration. Last, we tested moderating effects of measure factors. We analyzed 163 domestic companies to find out many significant suggestive points. First, relationship improvement capacity, e-business knowledge sharing capacity with business partners, and process innovation capacity are adopted as determinants of differentiation and competitive edges against competing firms. Second, e-business knowledge sharing capacity, and process innovation capacity are analyzed as the determinants of e-business integration in the firm which demand fluctuation in the market is high. On the other hand, among the determinants that require capturing ideas on new products, and strengthening the technological power, process innovation capacity are adopted as the determinants. These results provide us the foundation that the determinants that we have analyzed can impact the supply chain integration strategies which take into account the competitive environments.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2008.05a
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• pp.47-70
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• 2008

Cost efficiency is today the primary requirement in the paper and board industry. This has led therefore, to a greater preponderance of products with specifically designed functionality to take account of current industry needs. Continually increasing machine coating speeds together with these new coating colour components have put more emphasis on the importance of the correct rheology and water retention of the coating colours to achieve good runnability and end product quality. In the coating process, some penetration of the aqueous phase, to the base paper or board must occur to anchor the pre-coating to the base or the topcoat to the pre-coat. The aqueous phase acts as a vehicle not only for the binder, but also for the other components. If this water or material penetration is not controlled, there will be excessive material shift from the coating colour to the base, before immobilization of the coating colour will stop this migration. This can result in poor machine runnability, unstable system and uneven coating layer, impacting print quality. The performance of rheology modifiers or thickeners on the coating color have tended to be evaluated by the term, "water retention". This simple term is not sufficient to explain their performance changes during coating. In this paper we are introducing a new concept of "material retention", which takes note of the total composition of the coating colour material and therefore goes beyond the concept of only water retention. Controlled material retention leads to a more uniform z-directional distribution of coating colour components. The changes that can be made to z-directional uniformity will have positive effects on print quality as measured by surface strength, ink setting properties, print gloss, mottling tendency. Optical properties, such as light scattering, whiteness and light fastness delivery should also be improved. Additionally, controlled material retention minimizes changes to the coating colour with time in re-circulation giving less fluctuation in quality in the machine direction since it more closely resembles fresh coating for longer periods. Use of the material retention concept enables paper and board producers to have more stable runnability (i.e. lower process costs), improved end product quality (i.e. better performance of used chemicals) and/or optimized use of coating colour components (i.e. lower total formulation cost)

• The Korean Journal of Quaternary Research
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• v.22 no.1
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• pp.1-12
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• 2008

We investigated metal concentrations and oceanic environment changes that have occurred over the past several years by studying the hard coral Porites lutea, which inhabits tropical and subtropical areas. Soft X-radiographs clearly showed distinctive annual bands within 71 mm coral sample, which reflect changes in the oceanic environment over this period. There were large fluctuations in the major and minor element concentrations. Considering the physicochemical partition coefficient, some elements accumulated in the aragonite matrix in a mechanical manner, while others were affected by environmental factors. The concentrations of some heavy metals varied over a wide range, implying local environmental effects. The variation of Sr/Ca and Mg/Ca in coral skeleton clearly showed large-scale fluctuation over the specific intervals, implying environmental changes during this period. The concentrations of heavy metals also show high fluctuations, and roughly accord with Mg/Ca variation. In addition, Cu and Zn seem to show cyclicity-like peaks, coincide with Mg/Ca variation over the specific intervals. Such variation might be related to local pollution and oceanographic changes. More detailed investigation is necessary, including the pretreatment of coral skeleton sediment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.2
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• pp.146-156
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• 1988

This study was carried out to investigate the change of endosperm substance and seedling growth in rice seedlings for machine transplanting with use of two rice varieties, which Samgangbyeo (Indica${\times}$Japonica) and Dogjinbyeo (Japonica) were sown on May 8 with five levels of seeding density. 1. The total dry matter weight, leaf area, length of the longest root, number and length of new roots were negatively correlated with seeding density, and the plant height had the similar tendency to them from 20 days after sowing(DAS). 2. The rooting ability was negatively correlated with seeding density and decreased from 35 DAS in Dongjinbyeo. 3. The endosperm substance were exhausted at 25 to 30 DAS in Samgangbyeo and at 25 DAS in Dongjinbyeo. 4. The leaf area was more useful than the ratio of plant height to dry matter weight for judging the constitution of seedlings. 5. The reducing sugar contents in the endosperm were the greatest among parts of rice seedlings followed by leaf and root. The contents in leaf, root and endosperm reached maximal at 10 DAS, and varied with plant parts, seedling growth and varieties in different levels of seeding density. 6. The protein contents in leaf and root of rice seedlings became decreased with seedling growth., and were minimal values at 15 DAS. The content in endosperm was decreased soon after seeding, and minimal at 4 DAS with showing some fluctuation of protein content after then.