• Membrane and Water Treatment
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• v.7 no.2
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• pp.127-141
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• 2016

Electrodialysis (ED) is known to be a useful membrane process for desalination, concentration, separation, and purification in many fields. In this process, it is desirable to work at high current density in order to achieve fast desalination with the lowest possible effective membrane area. In practice, however, operating currents are restricted by the occurrence of concentration polarization phenomena. Many studies showed the occurrence of a limiting current density (LCD). The limiting current density in the electrodialysis process is an important parameter which determines the electrical resistance and the current utilization. Therefore, its reliable determination is required for designing an efficient electrodialysis plant. The purpose of this study is the development of a predictive model of the limiting current density in an electrodialysis process using response surface methodology (RSM). A two-factor central composite design (CCD) of RSM was used to analyze the effect of operation conditions (the initial salt concentration (C) and the linear flow velocity of solution to be treated (u)) on the limiting current density and to establish a regression model. All experiments were carried out on synthetic brackish water solutions using a laboratory scale electrodialysis cell. The limiting current density for each experiment was determined using the Cowan-Brown method. A suitable regression model for predicting LCD within the ranges of variables used was developed based on experimental results. The proposed mathematical quadratic model was simple. Its quality was evaluated by regression analysis and by the Analysis Of Variance, popularly known as the ANOVA.

• Journal of Navigation and Port Research
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• v.34 no.6
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• pp.503-509
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• 2010

Remarshaling is referred to a preparatory task of rearranging containers piled up in a stacking yard to improve the efficiency of loading. Selective remarshaling is required because the time for remarshaling known as large time-consuming task is not enough to remarshal all containers. In this research, we compare two previous researches in more objectively way: heuristic and genetic algorithm based approaches. In addition, we prove the effect of iterative reselection method on dwindling the gap between plan and execution due to the uncertainty of crane operation during execution. Simulation experiments under realistic uncertainty model show that heuristic approaches which have few computational complexity can cope with the uncertainty well when reselection interval is short, but genetic algorithm based approach has advantages when reselection interval that can ensure appropriate number of evolutions is given because of computational complexity for search.

• Journal of Korean Academy of Nursing
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• v.3 no.2
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• pp.15-30
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• 1973

Nursing education in Korea has made rapid progress recently. There is .: great deal of support with approval and encouragement of this progress. However, much disapproval of its validity has asserted some restraints on it. The aims of nursing education should be based on the principle that education is planned according to tile need much research has been made with such a viewpoint but much still remains unclear. The present study is aimed at establishing the needs for nursing manpower based on the biological demand for medical care. The needs for nursing manpower have been emphasized by many researchers and authorities on nursing education, and the prevailing medical trends also demand it. In this study, through the study of various hooks and records concerned, and the compiling of data analysis and questionnaires, I came to the following figures for the proposed needs of nursing manpower: There figures are greater than those calculated by another method by the government research program but it shows approximately the same final figure as that of the government report for the end of the target year. With these findings, I concluded that: 1) As the final purpose of the government medical project is to fulfill the needs of the national health (that is, to support the national needs for medical care), the plan of this project should follow the theory of biological demand for medical care, recognizing that the numbers will increase gradually. 2) Qualitative growth, based on the advanced and specialized nursing profession. should be promoted to meet the rapid growth of the medical needs of the nation in addition to promoting of investments for the facilities. and of the preparatory investments for education needs. 3) For efficient and economic utilization of nursing manpower, the improvement of wages, and the offering of free education is necessary. 4) Amendments to the low promising innovation and advancement of medical treatment; preparation of a national fund for medical care; and, changing of national attitudes to bring about greater concern are desirable.

• Journal of Radiation Protection and Research
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• v.46 no.3
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• pp.83-97
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• 2021

Background: The lifetime risk of lung cancer incidence due to radiation for nonsmokers is overestimated because of the use of the average cancer baseline risk among a mixed population, including smokers. In recent years, the generalized multiplicative (GM)-excess relative risk (ERR) model has been developed in the life span study of atomic bomb survivors to consider the joint effect of radiation and smoking. Based on this background, this paper discusses the issues of radiation risk assessment considering smoking in two parts. Materials and Methods: In Part 1, we proposed a simple method of estimating the baseline risk for nonsmokers using current smoking data. We performed sensitivity analysis on baseline risk estimation to discuss the birth cohort effects. In Part 2, we applied the GM-ERR model for Japanese smokers to calculate lifetime attributable risk (LAR). We also performed a sensitivity analysis using other ERR models (e.g., simple additive (SA)-ERR model). Results and Discussion: In Part 1, the lifetime baseline risk from mixed population including smokers to nonsmokers decreased by 54% (44%-60%) for males and 24% (18%-29%) for females. In Part 2, comparison of LAR between SA- and GM-ERR models showed that if the radiation dose was ≤200 mGy or less, the difference between these ERR models was within the standard deviation of LAR due to the uncertainty of smoking information. Conclusion: The use of mixed population for baseline risk assessment overestimates the risk for lung cancer due to low-dose radiation exposure in Japanese males.

• Journal of Convergence for Information Technology
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• v.11 no.3
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• pp.205-211
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• 2021

This study utilizes PhotoVoice, a qualitative research method, to explore the life experiences of retirees by age in depth and derive the social welfare implications required for successful aging of retirees. Two participants in the study were selected in their 70s, 60s, and 50s, and 24 photos, explanations, 44 stories, and 92 data collected through group activities and personal interviews were analyzed. With the perception of successful aging, those in their 70s were "Preparing for a High Level of Social Responsibility and Dignity," those in their 60s were "Life of Social Responsibility and Service with Embarrassment and Boeun," and those in their 50s were "Life of Self-reliance with Economic Stability and Consideration." In order to prevent social problems for retirees with longer old age, research and social welfare policy support for their social jobs and volunteer positions are urgently needed, and the sooner the preparatory education is implemented so that they can prepare enough. This study is significant in that it played an important role in presenting basic data for the preparation of social welfare alternatives for retirees.

• Korean Journal of Culture and Social Issue
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• v.11 no.1
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• pp.1-23
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• 2005

This article examines the relationship of career indecision, job search behavior, and employment among college seniors based on sub-scales of career indecision (lack of career information, lack of self-clarity, decisiveness, lack of necessity recognition, external Barrier). This study explored the effect of career indecision, job search behavior, and employment successes(number of application, number of interview, number of job offer) in longitudinal method. In result, career indecision had negative effect on job search behavior. In other words, the higher career indecision level is, the less job search behavior is performed. Especially, career indecision is connected with preparatory job search behavior and informal job search behavior. Another finding is that job search behavior in time 1 (first semester of college senior) had a strong effect on all of employment success variables in time 2(second semester of college senior). Finally, the theoretical and practical implications of this research were discussed. Based on the limitation of this study, several directions for future research were also suggested.

• Korean Journal of Applied Biomechanics
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• v.34 no.2
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• pp.53-62
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• 2024

Objective: The purpose of this study was to analyze the differences in kinematic factors according to stretching treatment, myofascial release treatment, and static stretching treatment conditions during squat. Method: Twelve males with resistance training experience participated in this study. Participants performed squats without treatment (Pre-Test), and performed squats after treatment with the myofascial release technique (MRT) and static stretching (SS) on different days (post-test). Squat movements were captured using eight motion capture cameras (sampling rate: 250 Hz), and the peak joint angles of the ankle, knee, hip, and pelvis were calculated for each direction. One-way repeated ANOVA and Bonferroni post hoc analyses using SPSS 27 (IBM Corp. Armonk NY, USA) were used to compare the peak joint angle of the lower extremity joints and pelvis among the normal condition (squat without treatment), MRT condition (squat after MRT treatment) and SS condition (squat after static stretching). The statistical significance level was set at .05. Results: It was observed that the maximum ankle joint flexion angle during squats was statistically reduced under conditions of myofascial release and static stretching (p<.05), in comparison to the scenario where no stretching was performed. Furthermore, static stretching was found to enhance the maximum hip flexion angle during squat (p<.05), whereas the myofascial release stretching technique resulted in the minimal posterior pelvic tilt angle (p<.05). Conclusion: Employing myofascial release stretching as a preparatory exercise proved to be more efficacious in maintaining body stability throughout the execution of high-intensity squat movements by effectively managing the posterior tilt of the pelvis, as opposed to foregoing stretching or engaging in static stretching.

• Management & Information Systems Review
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• v.29 no.3
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• pp.71-96
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• 2010

This article firstly reviewed Permanent Established(PE) concept of OECD and UN model tax treaty and compared it with that of Korean Corporate Income Tax Law(CITL). The various factors regarding profit like ways of deciding the local source profit, scope and calculation method which will be imputed to PE were also reviewed. Based on above, standard PE judgement basis and calculation method of local source profit were also studied by using actual cases in foreign corporation which performs plant construction & sales in Korea. Accordingly to properly solve the conflict regarding international tax and to protect the tax authority against the foreign corporation in Korea, by standing on equality, I now propose followings for the better concept of PE in Korea. Firstly, the article that a building site or construction or installation project constitutes a PE only if it lasts more than 6 months should be modified to reflect OECD model convention's criteria of 12 months. Second, the scope of 'subordinate attorney' which is regarded as PE under CITL is now including 'holding-delivery attorney', 'order attorney', and 'assurance attorney' as well as 'contract attorney'. This is overly limit the activities of foreign corporation. It had better be loosened only to include 'contract attorney' as OECD provisions. Third, the CITL limits the cases of preparatory and/or auxiliary place which is not regarded as PE, thus limit the foreign corporations' business by expanding the concept of PE. This had better be eased. Fourth, in deciding the amount of local source profits, the CITL stipulates to split the profits by the relevant contribution of transaction parties through 'profit split method'. To solve the conflict, the ways of profit split must be better clarified through providing object and detailed standard and basis.

• 대한공업교육학회지
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• v.32 no.1
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• pp.153-171
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• 2007

The purpose of this research was to investigate the degree of perceptional change of career education through overseas training of specialized high school teachers who take the leading role in applying Korean vocational education to reality. To accomplish this purpose, the following method were employed: 25 specialized department teachers of Keyngido educational institute who visited career education institute in USA and Canada were selected, and pretest and posttest were taken. Collected data were analyzed by Windows Korean version SPSS 14.0. M, SD, t-test and significant level p<.05 were employed for statistical analysis. The result of this research was as follows: There was significant difference in the degree of perceptional change of vocational education by overseas training of specialized high school teachers. But There was no significant differences in the management of vocational education curriculum(${\alpha}=.327$), reinforcement of preparatory training for technique contest(${\alpha}=.327$) in the statistical significant level(p<.05). The perception level of the trainees varied respectively in these domains. And means of posttest were relatively low in the comparison with those of pretest in the domains of visit of educational institute, educational facilities, scholarship and financial support, and reinforcement of preparatory training for technique contest. It is attributed to the Korea's uniqueness of culture, emotion, school system, educational facilities and financial support different from U.S.A. and Canada. The vocational education program of vocational education training institute in U.S.A. and Canada is mainly composed of industrial department, so there was no statistical significant difference(p<.05) in some questions taken by subjects of agricultural and commercial department. In conclusion, The overseas training program is very helpful for the perceptional change of vocational education and it is desirable to be expanded continuously.

• Women's Health Nursing
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• v.5 no.2
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• pp.262-277
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• 1999

The purpose of this study is to define the effects of the roles played by the Doulas : one group educated on the conventional Lamaze method known to have effects on birth pang during delivery process and the other group educated both on Lamaze and therapeutic touch. On the various factors of delivery, and thereby, provide for some basic data to develop an effective nursing intervention to relieve women of their birth pang. 136 mothers who were hospitalized in a general hospital from June 13, 1998 to May 13, 1998 to May 13, 1999 to deliver their first babies were sampled to be divided into control group, test group I and test group II and thus be subject to interviews and observations. As for the tool of study, melzack's(1975) 'pain scale', McCaffery's(1972) and Mcrachlan's(1974) 'pain expression scales' and Spielberger's (1975) 'anxiety scale' were used. The preparatory educational programs consisted of 5week Lamaze method and therapeutic touch. The research, design was quasi-experimental, non equivalent, posttest only control group design. The collected data were processed using the SPSS/PC statistics software for frequencies, means and one-way Anova as well as Tukey HSD and Scheffe test as post hoc for individual comparison. Moreover, chi-square test was used to test the differences between groups, while Pearson's correlation coefficients were analyzed to determine the correlations between anxiety and variables. The findings are as follows ; 1. The birth pain of the mothers delivering first babies scored in a subjective and objective pain scale; 1) There was a significant difference of subjective birth pain at 8~10cm opening of cervix between control group and two test groups. 2) There was no significant difference of objective birth pain as per opening of cervex among three groups in terms of sweating, facial movement, bodily posture and vocal changes. 2. There was no significant difference of trait anxiety among three groups. however, there was a significant difference of state anxiety during labor process between control group and two test groups. On the other hand, all the three groups showed a significantly lower level of anxiety during labor process than when they were carried to the hospital. 3. There was a significant difference of the time of total and first-stage labor among three groups, while there was a significant but small difference of the time elapsed from 8~10cm cervix open to the full among three groups. 4. Two test groups showed a higher frequency of natural deliveries than the control group. 5. Two test groups were subject to these drugs than the control group. In conclusion, it was found that the test group I and II showed a shorter delivery time than the control group, a higher frequency of natural delivery and a lesser use of anodyne or epidural. In particular, this study is significant to develop a nursing intervention service or a therapeutic touch which the nursing administrators can apply to their hospitals in marketing programs.