• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.2
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• pp.167-172
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• 2004

In the human skin, vitamin C (L -ascorbic acid) that is well known as the activated materials has effects that is skin anti-aging and wrinkle repair by giving impetus to collagen biosynthesis and anti-oxidation, and that is the sun screen, a wound recovering, inhibition melanogenesis and so on. In spite of its effects, vitamin C has the defects of the skin stimulation and easily oxidized instability by water, air, heat and light. For solving their matters, many investigation is advanced and its results are synthesized the various vitamin C derivatives. And yet they have not solved the unstable property of vitamin C and were still insufficient for the comparing with the effect of the pure vitamin C itself. In this study, in order to prepare vitamin C derivative of being improved the stability and to apply vitamin C effect in the skin, we prepared new vitamin C derivative, phytosphingosine ascorbate, by using phytosphingosine, one of sphingolipids, which have a distinguished skin affinity. Phytosphingosine ascorbate can be prepared as the ionic bond between amine group (-NH$_2$) of phytosphingosine and hydroxy group (-OH) of vitamin C by way of the relatively simple reaction. So the structure and properties of the synthesized phytosphingosine ascorbate was confirmed the use of elemental analysis (C 58.3 : H 9.3 : N 2.8 : O 29.5), MALDI TOF-MS (Mw=492.58), Ultraviolet spectra (268.5nm), lH NMR, FT-IR spectra, thermal analysis (m.p=l54$^{\circ}C$), HPLC and so on. And we could confirm the anti-bacterial and anti-oxidation effects. Based on these results, we could confirm to prepare a new material that was expected of both effects of vitamin C and phytosphingosine and that is improved properties of vitamin C.

• Korean Journal of Occupational Health Nursing
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• v.12 no.1
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• pp.80-88
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• 2003

Rehabilitation has emerged in recent years as major topic for the handicaped in industrial accident compensation insurance(IACI). Specially social support helps the handicaped adjust themselves psychosocially to handicap. This study was conducted to examine different contents and perceived social support, and provide guidlines for specific and proper rehabilitation for the handicaped of IACI. This study is a descriptive study which were collected through two phases using structured questionnaire. In the first stage, surveys were performed via telephone interviews. In the second stage, surveys were performed via home-visit subjects in the first stage included the handicaped of IACI. Finally data were collected from 338 subjects and analyzes by SPSS/PC+10. The instruments of this study were the perceived social support scale which developed by Lee(1996). These scales in the form of 5-point Likert type, consists of 20 items, including 3 subscales of emotional support, informational support, instrumental support. The mean score of social support was 57.2, emotional support 21.0, informational support 21.2 and instrumental support 15.2. The mean of depression for psychosocial factors is 37.5. Threre were significant differences in total perceived social support; age, job status, handicaped degree in IACI, post-traumatic complication and use of instrument. Emotional support was significant differences; age, number of dependent family, job status, handicaped degree in IACI, use of instrument and depression. Informational support was significant differences; job status, posttraumatic complication, use of instrument and depression. Instrumental support was significant differences; sex, job status, handicaped degree in IACI, use of instrument, and depression. The current system of the Labor Welfare institute is not appropriate for solving health problems of the handicaped in IACI. Therefore, it is necessary to develop the plan which can provide the handicaped in IACI high-quality rehabilitation services, so that they must use those services in the community without being dependent on hospitals. This study proposes home visit nursing services as the way to provide various health services within community for the handicaped in IACI.

• Journal of the Korean association of regional geographers
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• v.14 no.6
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• pp.709-717
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• 2008

This study is to analyze environmental problems which have caused by changes of the population and agriculture in North Korea. Main results of the research are following. First, Population of the North Korea shows lower increase ratio less than 2% growth from 1970's to middle of 1990's. This is interpreted by food shortages. Second, population distribution by provinces represented that northern and eastern part of the North Korea were comparatively lower and other western areas were higher. Third, Food situation of the North Korea was relatively better in 1970's, but, 1990's was the worst in the way. Fourth, on the agricultural productivity according to each province, western areas possessing more plains were more higher than mountainous areas of the northern and eastern parts of North Korea. Fifth, Growth ratio of food production and population have grown very steadily until 1990's, but the increase ratio of population exceeded food productivity after 1990's. Sixth, Cropland reclamation for improving these situation have caused deforestation and environmental problems and especially eastern and northern areas became more serious. For the solving these problems of North Korea, it is necessary to get the help of South Korea and international societies with efforts by itself.

• Journal of Korean Academy of Nursing Administration
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• v.6 no.3
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• pp.333-345
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• 2000

The health care environment becomes more competitive every day. It has fallen to nurse managers - from vice presidents of patient care to nurse managers and their assistants - to recruit and develop a workforce that successfully meets the needs of both patients and the organization. This means employees who demonstrate advanced critical thinking skills, creative problem solving, and sound decision making skills combined with clinical skills and patient advocacy. The environment which nurse managers create and the way they relate to their workforce, are pivotal to organizational viability. Especially leadership of first -line nurse managers contributes to the success of their organizations. First-line nurse managers are deserved to be one of the most administrative supervisors through the middle stratum in a hospital organization as being a manager in the field service if assessed from the overall aspects of hospital, as being an interim managers in the nursing department as well as being a supreme supervisor in a unit in terms of an organizational structure in the hospital. Similarly, as a compete leader, the first-line nurse managers have not only a professional which is qualified to perform a role of appropriate coordination with medical staff and key personnel but also hold an important key position a being responsible for performing his or her given role. The first-line nurse manager is expected to manage human and fiscal resources in ways not required before. While an identified need for well-prepared first-line nurse manager continues to plague the profession, first-line nurse managers often have difficulty providing the leadership required. The need leadership training to function effectively in their positions. But we hardly find a useful leadership training program for first-line nurse managers, therefore the purpose of this study was to developed the leadership training program for them. The steps of leadership program development were below: 1st step, 2 studies were done before develop a leadership program. One was done to ask to first-line nurse managers what they want to learn through leadership training, the other one was to ask the staff nurses what their opinions are for their first-line nurse managers leadership. 2nd step was searching other leadership programs contents. The results of this study were below: The total amount of hours is 24. Leadership training program contents are : Future of nursing profession (210min), understanding basic factor's of leadership and leadership theories(310 min), self understanding as first- line nurse managers(320 min), basic principle and practice of interpersonal relationship(210 min), assertiveness training, conflict management (180min), and group study(210min). This is challenging time to be a leader, especially in nursing. As nurse managers look toward the new millennium, it seems as through the same struggles are ahead that are behind. So nurse managers need to embrace change with a positive attitude. They need to demonstrate risk taking and support it in their staffs. All these things are possible that after they participate the leadership training program.

• Journal of Science Education
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• v.44 no.3
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• pp.331-344
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• 2020

This study aims to find meaningful implications for the development of Korean elementary school math education courses and textbooks by comparing and analyzing the number and arithmetic areas of Korean and Canadian math textbooks in fifth and sixth grades. To this end, the textbook composition system of Korean and Canadian elementary schools was compared and analyzed, and the number and timing of introduction of math textbooks and math textbooks by grade, and the number in fifth and sixth grade and the learning contents of math textbooks were compared and analyzed. The following conclusions were obtained from this study: First, it is necessary to organize a textbook that can solve the problem in an integrated way by introducing the learned mathematical concepts and computations naturally in the context of problems closely related to real life, regardless of the type of private calculation or mathematics area. Second, it is necessary to organize questions using materials such as real photography and mathematics, science, technology, engineering, art, etc. and to organize textbooks that make people feel the necessity and usefulness of mathematics. Third, sufficient learning of the principles of mathematics through the use of various actual teaching aids and mathematical models, and the construction of textbooks focusing on problem-solving strategies using engineering tools are needed. Fourth, in-depth discussions are needed on the timing of learning guidance for fractions and minority learning or how to organize and develop learning content.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.5
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• pp.45-61
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• 2023

The start-up rate is increasing due to the government's start-up support policy, but it is true that the continuous survival rate and growth rate of companies are lower than that of the start-up rate. As part of increasing the survival and growth rate of startups, the importance of start-up mentoring has been highlighted, and companies selected for the Government's startup support project are increasingly having mentoring opportunities for corporate growth. In order to determine the relationship between start-up mentoring and entrepreneurial alertness as a way to generate management performance, this study examined how start-up mentoring affects entrepreneurial alertness and management performance. In addition, the government's support project was divided into companies with less than three years of start-up and companies with more than three years of experience, which are the criteria for early and leap companies, and analyzed whether each group has a moderating effect. As a result of the analysis, it was found that the mentoring problem-solving function had a significant effect on the ability to evaluate entrepreneurial alertness, and the motivation function of mentoring had a significant effect on all factors of entrepreneurial alertness. In addition, although mentoring functions did not have a moderating effect on entrepreneurial alertness depending on the work history between companies less than 3 years and companies for more than 3 years, there was a difference in factors affecting entrepreneurial alertness between groups with low and high work history. The implications of this study can contribute to the advancement of start-up mentoring programs by studying the impact of mentoring factors on entrepreneurial alertness when providing mentoring to start-up companies selected for the government's start-up support project.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.11B
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• pp.1501-1509
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• 2001

Recently, the use of wireless communication systems has been rapidly increasing, which results in a difficult problem in efficient control of limited frequency resources. As a way of solving this problem, the ultra wideband time hopping impulse radio system attracts much attention. The impulse radio system communicates pulse position modulated data using Gaussian monocycle pulses of very short duration less than 1 nsec. Thus the transmitted signal has very low power spectral density and ultra wide bandwidth from near D.C. to a few GHz. It is blown that it hardly interferes with the existing communication systems because of its very low power spectral density. The purpose of this paper is to characterize multipath propagation of the impulse radio signal and to evaluate the performance of the correlator-based receiver for the multipath environments. In this paper, we consider the deterministic two-path model and the statistical indoor multipath model of Saleh and Valenzuela. For the two-path model the output of the correlator with the ideal reference waveform varies according to the relative difference between the indirect path delay and the time interval of PPM, and to the indirect path gains. In addition, the characteristics of bit error rates is measured for the two models through computer simulation. The simulation results indicate that the performance of the impulse radio system depends both on the relative difference between the indirect path delay and the time interval of PPM, and on the indirect path gains. Furthermore, it is observed that the reference signal designed for the AWGN channel can not be applied to the multipath channels.

• Journal of the Korean School Mathematics Society
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• v.9 no.4
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• pp.557-573
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• 2006

The purpose of this study is to examine the usefulness of teaching Maple in College Mathematics Education. The subject are 60 students of college of science in H university and C university located in Daejeon. They were divided into two parts; an experimental group (group I, group II, each of 20 students) and a control group (group III of 20 students). The group I and II are provided calculus lecture in class as well as Maple lab, while group III are lectured only in class. In order to know the effectiveness of using Maple, a test is designed in the way that group I is allowed to use both pencil and Maple, while group II and III are restricted to use only pencil. The result of this study is as follows. i) According to the performance of testing exam, there is no significant difference between three groups (p>.05) when they are allowed to use only pencil. ii) The achievement of group I is much higher than that of group II and III (p<.05) when they were provided both pencil and Maple. iii) Lot of students in group I who fail to solve with pencil can succeed in solving problems using Maple.

• Journal of Educational Research in Mathematics
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• v.16 no.3
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• pp.251-272
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• 2006

The purpose of the present study is to explore the process of teacher change as elementary school teachers participated in a community focused on improving mathematics teaching. To do so, a professional community lot improving instructional practice consisted of a group of voluntary elementary school teachers. The professional community provides participating teachers with great opportunities to share their understanding of practical knowledge related to mathematics teaching and learning and change mathematical beliefs as well as to learn pedagogical content knowledge. This study approached to teacher professionality in terms of mathematical beliefs and teaching practice. The change of teaching practice was measured coherently both with a questionnaire and with a mathematics teaching standard developed for this study. The findings of this study point out that techers' beliefs about how students learn mathematics have chantged. This study also indicated that after participating in the professional community focused on improving mathematics teaching, teachers' mathematical teaching is changed toward the more students' oriented way. Especially, it is observed that the meaningful change in participating teachers' teaching practice took place with respect to the role of teachers, students' interaction, mathematical tasks, and problem solving. Finally, this study implies that teachers can have an opportunity to change their beliefs and deepen their professionality about elementary mathematics teaching and learning through participating in the community of practice, through which participating teachers can share their practical knowledge and their understandings about teaching and learning of elementary mathematics.

• Korea Science and Art Forum
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• v.37 no.2
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• pp.101-112
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• 2019

Regardless of the size, the role and meaning of the space required for human daily life are the same. Especially, as the spatial design is small and the size is small, the careful design and problem solving are needed to enable comfortable and convenient life even in a narrow space. The purpose of this study is to design a convergence model that utilizes the advantages of BIM, which can simulate actual design based on a new one-person housing space design plan optimized for one person. This study applied the BIM design technology to one-person housing 2D design, and the suitability examination and the space optimization design of the interior design were carried out. As a result of the study, utility of space improvement, consideration of housing environment, interference check, application of eco-friendly housing system, and MEP design item were derived. Therefore, BIM space design in interior space has been confirmed as a way to overcome limit and inefficiency of 2D design which is applied to actual space by various space design elements. Based on the results of this study, the One-person housing space model, which is applied to the study, is a pure creation designed based on various one-person housing of social and cultural peculiarities derived from previous research. This design example was applied to BIM technology to confirm the detailed and practical design possibility.