• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.1012-1016
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• 2002

This paper describes a research work of developing computer-aided design of a product with bending and piercing for progressive working. An approach to the system for progressive working is based on the knowledge-based rules. Knowledge for the system is formulated from plasticity theories, experimental results and the empirical knowledge of field experts. The system has been written in Auto-LISP on the Auto-CAD with a personal computer and is composed of four main modules, which are input and shape treatment, flat pattern layout, strip layout, and die layout modules. The system is designed by considering several factors, such as bending sequences by fuzzy set theory, complexities of blank geometry, punch profiles, and the availability of a press equipment. Strip layout drawing generated in the strip layout module is presented in 3-D graphic forms, including bending sequences and piercing processes with punch profiles divided into for external area. The die layout module carries out die design for each process obtained from the results of the strip layout. Results obtained using the modules enable the manufacturer for progressive working of electric products to be more efficient in this field.

• Korean Journal of Social Welfare
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• v.64 no.2
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• pp.31-54
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• 2012

Along with increasing mothers' employment, work-family reconciliation has been recognised as a key policy agenda in contemporary welfare states. Although various policy instruments have been introduced and expanded in recent years, the problem of time allocation within couples still remains as a fundamental issue, which has been largely underresearched at a micro perspective. In this context, this study aims to identify dominant types of work-family time allocation within married couple, and to apply these types to the Korean case using the fuzzy-set ideal type analysis. Further, a series of multiple regression analyses will be implemented to find factors affecting each ideal type of work-family time allocation. The 1999 and 2009 Korea Time Use Survey datasets will be adopted for the analyses. Married couples are selected as samples only when men work 40 hours or more per week and they have at least one pre-school child. Empirical analyses cover three parts. First of all, four ideal types on work-family time allocation are classified by intersecting two core variables - the ratio of men's (paid) working and family (caring time plus domestic work) time to total working and family time. In this research, the four types will be labelled the traditional male breadwinner model (TM, high working and low family time), the dual burden model (DB, shared working but low family time), the family-friendly male breadwinner model (FM, high working but shared family time), and the adaptive partnership model (AP, shared working and shared family time). By comparing the composition of the four ideal types in 1999 and 2009, it will examine the trend of work-family time allocation in Korea. In addition, multiple regressions will be useful for investigating which characteristics contribute to the different degree of each fuzzy ideal score in the four models. Finally, policy implications and further research agenda will be discussed.

• The Transactions of the Korea Information Processing Society
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• v.7 no.4
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• pp.1279-1289
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• 2000

Recently, research activities for combining portable computer technology and wireless communication technology are in progress to realize mobile computing environment that designed to support mobile hosts in the existing network environments. For PCN environments, the location management strategies are particularly emphasized among various strategies necessary for the mobile computing environment. Location management strategy for PCN environment, which is mostly based on the IS-41 standards brings an issue that additional network traffics are generated to deliver updata messages to home location server whenever a mobile host changes its location server. In this paper, we propose an innovative updata strategy and a search strategy that resolves the problem shown in the IS-41 scheme for HLR/VLR structure of CDMA environments. Also, this paper presents the performance comparison of proposed scheme and scheme used in IS-41 obtained from a simulation. The simulation was conducted based on the number of messages, the rate of database accesses, and the number of hops visited when the location management scheme is executed.

• Korean Journal of Cognitive Science
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• v.14 no.2
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• pp.27-35
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• 2003

The present study, focusing on the stress-shift constructions, examines the tendency of young children to give wrong wide scope interpretation in language acquisition and questions the validity of the guess pattern hypothesis argued by Grodzinsky & Reinhart (1993). According to the hypothesis, children know that they have to construct a reference-set, keep two representations in working memory, and check whether the interpretation needed in the given context justifies selection of competing reference sets, but their working memory is not big enough to hold the materials needed to complete the execution of this task. Hence they give up and resort to a guess. 1 carried out an experiment of 16 Korean children aged 3;9 to 6;2 to find out whether children have more difficulty in the interpretation of stress-shift constructions than of constructions with a nuclear stress, and therefore perform the interpretation of the former by guessing. Assuming that the tendency is caused by a deficiency in contextual computation rather than reference set computation, I try to explain it in terms of pragmatic considerations.

• The Journal of Fisheries Business Administration
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• v.24 no.2
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• pp.69-82
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• 1993

The purpose of this paper is to estimate production function in the coastal fishing, especially long bag set net fishing and trap fishing using Cobb-Douglas production function with the three main variables: fishing quantity per tonage(WQFP), the number of working persons per tonage(WEMP), and the number of utilized fishing equipments per tonage(WEQU). The statistical results of such estimation reveal that fishing quantity per tonage can be expressed as a function of the number of working persons per tonage and the number of utilized fishing equipments per tonage. The estimated coefficients of WEMP and WEQU are statistically significant and also satisfy the requirements of Cobb-Douglas production function. This study also estimates marginal rate of technical substitution of labor in terms of capital (MRT $S_{LK}$ )in each long bag set net fishing and trap fishing. The resuits of this study show us that trap fishing has the technical characteristic of constant returns to scale(CRS) but long bag net fishing has that of decreassing returns to scale(DRS).

• Korean Journal of Human Ecology
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• v.22 no.5
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• pp.419-431
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• 2013

This study examined the childcare use pattern of the working mothers with preschool children and the factors affecting their use of multiple childcare. The 7th wave data of "Korea Welfare Panel Study" were analyzed for this study. The working mothers with preschool children were selected from the data set and a total of 292 working mothers were included in the analysis. More than 70% of the working mothers were using only one kind of childcare, mostly childcare center and kindergarten and 22.5% of the mothers were using more than two of childcare arrangements. Child factors, maternal factors, household factors, and economic factors were included in the hierarchical logistic regression model in the presented order to predict the use of multiple childcare. The results showed that the child's age and maternal education were positively related to the use of multiple childcare, while whether both parents live with the child, number of children within household, and the poverty status were negatively related to the use of it. Based on these results, we can confer that the main motive for multiple childcare use is to provide various experiences for their children.

• Korea Journal of Hospital Management
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• v.4 no.2
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• pp.1-20
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• 1999

Objectives: Quality of Working Life(QWL) is a set of employee's physical, mental conditions which are perceived at their work. Most employees and managers are concerned about the quality of working life as a strategy for improving organizational effectiveness. The purpose of this study is to investigate the relationship between QWL and organizational effectiveness of employees at the general hospital. Methods : Data were collected by self-administered questionnaires at the general hospital in Kyunggi-Do. Survey was conducted to 675 workers. QWL was measured by using 5 items from the scale developed by Walton(1973). Organizational effectiveness was measured by measuring organizational commitment, intention of job-shift, and job satisfaction. Results: The recognitions to each component of QWL were significantly different by socio-demographic characteristics such as sex, age, education levels and working duration. Also, QWL were significantly different by types of organizational culture. Multiple regression analysis and multiple logistic regression analysis were applied to find the relationship of QWL and organizational effectiveness. As a result, job-pride, compensation, working condition, human relationship and development showed significant relationship with organizational effectiveness. Conclusions: These results show that QWL is significantly related to organizational effectiveness. So we expect that this result will be used as basic informations for management and motivation of employees at the general hospital.

• Science of Emotion and Sensibility
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• v.14 no.4
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• pp.605-616
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• 2011

The present study examined memory accuracy for faces with positive, negative and neutral emotional expressions to test whether their emotional content can affect visual working memory (VWM) performance. Participants remembered a set of face pictures in which facial expressions of the faces were randomly assigned from pleasant, unpleasant and neutral emotional categories. Participants' task was to report presence or absence of an emotion change in the faces by comparing the remembered set against another set of test faces displayed after a short delay. The change detection accuracies of the pleasant, unpleasant and neutral face conditions were compared under two memory exposure duration of 500ms vs. 1000ms. Under the duration of 500ms, the accuracy in the pleasant condition was higher than both unpleasant and neutral conditions. However the difference disappeared when the duration was extended to 1000ms. The results indicate that a positive facial expression can improve VWM accuracy relative to the negative or positive expressions especially when there is not enough time for forming durable VWM representations.

• Journal of Radiation Protection and Research
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• v.28 no.2
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• pp.145-154
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• 2003

By optimizing the radiation protection the collective dose and individual dose could be reduced during YGN #4 $5^{th}$ outage in 2001. The collective doses for the two high radiation jobs decreased to 85% and 65% of expected doses. The proportion of workers with low dose (below 1mSv) exposure increased 4% while the proportion of workers with over 3mSv and 5mSv exposure are decreased to 2%, 1% respectively. But none is exposed over 8mSv for the annual dose. To aid decision of utilizing the robot, cost- benefit analysis was performed and reasonable point was proposed to use the robot. For the first time job, repeated ALARA meeting and mock up training were implemented to set up working procedure by identifying the trouble. To easily set up standard procedure, mockup process was videotaped and reviewed during ALARA meeting. Monitoring is a good approach to chase radiological working condition such as working time, dose rate. behavior of workers, especially for high radiation work. Those data were estimated and adjusted from the stage of work planning to mock up. At the stage of actual work the monitoring data were compared to the estimation and recorded to database. This database will not only be used as a powerful tool for dose optimization at the following outage but also as a guideline to dose constraint set up for optimization for each specific situation.

• Korean Journal of Radiology
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• v.1 no.1
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• pp.19-24
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• 2000

Objective: In order to investigate the functional brain anatomy associated with verbal and visual working memory, functional magnetic resonance imaging was performed. Materials and Methods: In ten normal right handed subjects, functional MR images were obtained using a 1.5-T MR scanner and the EPI BOLD technique. An item recognition task was used for stimulation, and during the activation period of the verbal working memory task, consonant letters were used. During the activation period of the visual working memory task, symbols or diagrams were employed instead of letters. For the post-processing of images, the SPM program was used, with the threshold of significance set at p < .001. We assessed activated brain areas during the two stimulation tasks and compared the activated regions between the two tasks. Results: The prefrontal cortex and secondary visual cortex were activated bilaterally by both verbal and visual working memory tasks, and the patterns of activated signals were similar in both tasks. The superior parietal cortex was also activated by both tasks, with lateralization to the left in the verbal task, and bilaterally without lateralization in the visual task. The inferior frontal cortex, inferior parietal cortex and temporal gyrus were activated exclusively by the verbal working memory task, predominantly in the left hemisphere. Conclusion: The prefrontal cortex is activated by two stimulation tasks, and this is related to the function of the central executive. The language areas activated by the verbal working memory task may be a function of the phonological loop. Bilateral prefrontal and superior parietal cortices activated by the visual working memory task may be related to the visual maintenance of objects, representing visual working memory.