• BMB Reports
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• v.48 no.4
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• pp.193-199
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• 2015

Degenerative retinal diseases affect millions of people worldwide, which can lead to the loss of vision. However, therapeutic approaches that can reverse this process are limited. Recent efforts have allowed the possibility of the stem cell-based regeneration of retinal cells and repair of injured retinal tissues. Although the direct differentiation of pluripotent stem cells into terminally differentiated photoreceptor cells comprises one approach, a series of studies revealed the intrinsic regenerative potential of the retina using endogenous retinal stem cells. Muller glial cells, ciliary pigment epithelial cells, and retinal pigment epithelial cells are candidates for such retinal stem cells that can differentiate into multiple types of retinal cells and be integrated into injured or developing retina. In this review, we explore our current understanding of the cellular identity of these candidate retinal stem cells and their therapeutic potential for cell therapy against degenerative retinal diseases. [BMB Reports 2015; 48(4): 193-199]

• Asia pacific journal of information systems
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• v.7 no.2
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• pp.225-266
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• 1997

A Causal Transition Model of the IT impact on organization is proposed. The model is based upon the premise that the IT impact is a multi-phase, multi-realm phenomenon, and that the IT impact in one organizational realm logically transpires to another realm, thus forming complex causal webs among them. Two exploratory research studies, the one qualitative and the other quantitative, were conductea to validate the model in a setting involving major structural reorganization of the organizations' IT function. The research results provide support for the general theory structure of the model. The findings include: ⅰ) the IT impact manifests on multiple organizational realms, with different degrees of strength, ⅱ) the impact on the realms follow a particular causal transition path among them, and ⅲ) the IT impact manifests on and through the information processing aspect of work. The results, however, indicate that people's perception of the IT impact is strongly mitigated by the IT relevance of work, and that the organization is affected as much by the structural arrangement surrounding and accompanying the IT as by the technology itself, suggesting that the IT impact is an organizational phenomenon as well as a technological phenomenon. The implications of the research results are discussed at the end.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.11a
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• pp.41-46
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• 1997

Lower esophageal sphincter (LES) is characterized by the ability to maintain a sustained pressure, and to relax allowing the passage of a bolus, whereas the esophagus is normally relaxed and contracts only briefly when required to produce peristalsis (fig. 1). The neuromuscular mechanisms that participate in the physiological regulation of these functions are not well understood, but it is thought that LES tone is spontaneous and regulated mostly through myogenic mechanisms, whereas LES relaxation and esophageal contraction are induced by neural mechanisms. Gastroesophageal reflux represents the effortless movement of gastric contents from stomach to esophagus. Because this phenomenon occurs in virtually everyone multiple times every day and in the majority of people without clinical consequences, the reflux per se is not disease. However in some cases, it can be pathologic, producing symptoms and signs called gastroesophageal reflux disease (GERD), which mechanism is not well known. It may result in heart burn, chronic esophagitis, aspiration pneumonia, esophageal strictures, and Barrett's esophagus.

• Proceedings of the Korean Statistical Society Conference
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• 2000.11a
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• pp.97-104
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• 2000

Time-related underemployment exists when a person's employment is insufficient in terms of the volume of work. Two alternative definitions can be considered based on a longer-term view or a shorter-term view and these were designed into a single questionnaire. We conducted a pilot sample survey with about 6,000 respondents in Korea. The estimates of underemployment using the two definitions show some differences given the ages, genders, industrial areas and main activities of the respondents. A larger number of people could be identified as underemployed when the longer-term view is used than when the shorter-term view is used, but there is a greater cost associated with the former. The cost-benefit of the interviewers' time was investigated by multiple visits to households. Biases and costs are also analyzed using the results of the comparison of the decrease in non-responses with the increase in the costs for the interviews.

• Journal of Chest Surgery
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• v.26 no.8
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• pp.643-645
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• 1993

It is generally acknowledged that congenital coronary artery fistula is an abnormal communication of the coronary artery with the right ventricle, right atrium,left atrium and left ventricle. In young people the symptoms are unusual , but significant symptoms and complications appear among the older age group such as congestive heart failure, subacute bacterial endocarditis, coronary steal syndrome, aneurysm formation, rupture, and pulmonary hypertension. Therefore, early surgical treatment is recommended. We experienced a case of coronary arteriovenous fistula that was involving the circumflex branch of the left coronary artery with the right ventricle. It was 10mm in diameter with multiple vegetation. We repaired the fistula under extracoporeal circulation. The patient was discharged in a healthy condition twelve days after operation .

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.7
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• pp.903-909
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• 2018

We propose laser scanner sensor system based walking pattern and tracking method of multiple human. This system uses laser scanners sensors and is applicable to wide and crowded area such as hospital and medical care center. The primary objective of this research is to promote the development of robust, repeatable and transferable software for security system that can automatically detect, track and follow people in public area. We developed the method of human identification for this system. Our method is following: 1. Best-walking pattern data are obtained by the help of human position and direction data obtained by laser scanners. 2. Human identification is conducted by calculating the correlation between the step length of walking human. It becomes possible to conduct human identification even in crowded scenes by estimating the movements of waling human' feet are periodic. In the experiment in the station, some effectiveness of this method became clear.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2006.06a
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• pp.329-333
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• 2006

New computing paradigm in ubiquitous computing environments is revolutionizing the way people interact with computers, services and the surrounding physical spaces. In order to provide stronger authentication, MIST proposed an authentication framework for ubiquitous computing environments and assigned confidence values to some authentication methods to facility the combining. However, the assigned confidence values lack sufficient evidence. In this paper reliable confidence values for each authentication method used in MIST is proposed. These confidence values can combine multiple confidence values in some manner, producing a more accurate net confidence value. Authentication entities with confidence values allows the authentication framework to blond nicely into ubiquitous computing environments.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.5
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• pp.723-737
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• 1995

The purposes of this study were to investigate 1) the difference of cognitive evaluation on body exposure of female clothing, ann 2) purchase frequency and intention of wearing according to demographic variables. The instrument of this study consisted of response scale and stimuli. Thirty three items of 7.point Likert scale were developed to measure cognitive evaluation of the people who responded. The stimuli were 7 types of clothing, differing exposure parts and style on line drawing. The sample included 450 subjects, consisting of 231 in Seoul and 219 in Chun-nam Province. Statistics applied for analysis were frequency, percentage, mean, standard deviation, correlation, t-test, F-test, Duncan's multiple range test, factor analysis. The Results were: 1. Constructing factors of cognitive evaluation consisted of elegance, sensuality, attraction, individuality. There were significant differences in every factor on each types of clothing. 2. The evaluation toward each types of clothing was influenced by the subjects' sex, age, and residence. 3. Purchase frequency and intention of female subjects' wearing were very low, and there were significant differences on demographic variables.

• Journal of the Korean Society of Safety
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• v.8 no.3
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• pp.73-77
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• 1993

Automation and mechanization of work make people put the machine into operation and watch the state of operations. In the process of those works, they are apt to have accidents caused by their carelessness. To reduce such accidents, we can practise TOUCH and CALL, which Is to Indicate and ascertain the dangerous parts at every process before performing works. The objectives of thls study are to show quantitatively the efficiency of TOUCH & CALL and to examine the effects of S-R compatibility. The results show that reaction time is longer(0.138-0.279sec.) in case of indicating with finge,s and shouting than that of responding only visually. On the other hand, the error rate decreases by 3.3 times-7times. From this, it is considered to verify quantitative estimation on multiple feedback of TOUCH & CALL.

• Knowledge Management Research
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• v.5 no.1
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• pp.19-38
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• 2004

The present paper examines the effect of "community of learning" factors as well as learning and contextual factors on the e-learning performance empirically. The concept of community of learning, which was derived from community of practice, has not been emphasized in previous studies on e-learning. Data were collected from 226 people who had experienced e-learning and multiple regression analysis was used to analyze the data. The results are as follows; First, learning motivation and appropriateness of learning contents, ease of system use, and knowledge sharing have a positive effect on learner's satisfaction. Whereas, learning motivation, appropriateness of learning contents, ease of system use, knowledge sharing, and activated communication are appeared to affect the ability of performing tasks significantly.