• Title/Summary/Keyword: Field Study

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Antioxidant and Cellular Protective Activities of Ecklonia cava Extracts against Reactive Oxyegen Species (감태(Ecklonia cava) 추출물의 항산화 및 세포보호 활성)

  • Yoo, Cha Young;Kim, Si Yun;Park, Jung Won;Sung, Soo An;Kim, Da Ae;Park, Jee Hyun;Xuan, Song Hua;Park, Soo Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.41 no.3
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    • pp.287-294
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    • 2015
  • In this study, we investigated the antioxidative effects of brown seaweed Ecklonia cava extract and its subfractions. All experiments were performed with 50% ethanol extract, ethyl acetate fraction and aglycone fraction of E. cava. The free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activities ($FSC_{50}$) of ethyl acetate fraction ($FSC_{50}=6.98{\mu}g/mL$) and aglycone fraction ($7.03{\mu}g/mL$) are similar to that of (+)-${\alpha}$-tocopherol ($8.98{\mu}g/mL$) which is a reference control. Reactive oxygen species (ROS) scavenging activity (total antioxidant capacity, $OSC_{50}$) of the aglycone fraction ($OSC_{50}=14.48{\mu}g/mL$) on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system using the luminol-dependent chemiluminescence assay was the strongest among all extract and fractions. However, all samples showed lower antioxidant activities than that of L-ascorbic acid ($6.88{\mu}g/mL$) known as a powerful antioxidant. The protective effect of 50% ethanol extract on the $^1O_2$-induced cellular damage of human erythrocytes was dependent on the concentration from 5 to $50{\mu}g/mL$. Both ethyl acetate fraction and aglycone fraction showed strong cellular protective activities at $10{\mu}g/mL$, where the cellular protective effects (${\tau}_{50}$) of each fraction were recorded 442.0 min and 539.9 min, respectively. Three kinds of extract/fractions of E. cava showed much greater cellular protective activities at $10{\mu}g/mL$ than that of liposoluble antioxidant (+)-${\alpha}$-tocopherol (40.6 min) which is a reference control. These results suggest E. cava extracts and its fractions can be applied as an antioxidant ingredient in a field of cosmetics.

Flora of aquatic and wetland habitats on Jeju Island (제주도의 수생 및 습생 식물상)

  • Kang, Dae-Hyun;Yim, Eun-Young;Moon, Myung-Ok
    • Korean Journal of Plant Taxonomy
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    • v.45 no.1
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    • pp.96-107
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    • 2015
  • This study presents a comprehensive account of the flora of hydrophytes and hygrophytes on Jeju Island. This approach aims to contribute to fundamental information about the conservation of plant diversity in wetlands. Field surveys were carried out from May of 2010 to September of 2014 in various types of wetlands on Jeju Island. A total of 189 taxa, including 52 families, 98 genera, 181 species, 6 varieties, 2 forma and 189 taxa, were found. Among them, 99 taxa (38 families, 60 genera, 96 species and 3 varieties) were hydrophytes and 90 taxa (23 families, 45 genera, 85 species, 3 varieties and 2 forma) were hygrophytes. In addition, Eleocharis${\times}$yezoensis H. Hara (Cyperaceae) was newly added to the flora of Korea. The protected wild plants designated by the Ministry of the Environment were 5 taxa, including Brasenia schreberi J. F. Gmel. and Dysophylla yatabeana Makino. The endangered species found included one Critically Endangered Species (i.e., Mankyua chejuense B.-Y. Sun, M. H. Kim & C. H. Kim), 5 Endangered Species (e.g., Lysimachia leucantha Miq.) and 7 Vulnerable Species (e.g., Tillaea aquatica L.). The floristic regional indicator plants found in this area were 44 taxa comprising 10 taxa of grade V, 7 taxa grade IV, 15 taxa of grade III, 5 taxa of grade II, and 7 taxa of grade I. The identified naturalized plants were 10 taxa; 8 families, 8 genera, 9 species and 1 variety. In the wetlands on Jeju Island, high plant species diversity was shown, and a number of rare plants and phytogeographically important plants were found. For these reasons, we consider that the wetlands on Jeju Island are very important areas from a botanical point of view. It is necessary to establish specific protection and maintenance policies in an effort to conserve these wetlands and species.

Development of Environmental-friendly Cleaning Agents Utilizing Organic Acids for Removal of Scale on the Wall of Cleaning Beds and Distribution Reservoirs in the Waterworks (유기산을 이용한 상수도 정수장 및 배수지 벽면 스케일 세척용 친환경 세정제 개발)

  • Lee, Jae-Ryoung;Yoon, Hee-Keun;Bae, Jae-Heum;Shin, Hyun-Duk
    • Clean Technology
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    • v.18 no.3
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    • pp.272-279
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    • 2012
  • In this study, an environmental-friendly cleaning agent utilizing organic acids and various additives has been developed and applied to the field for removal of scale deposited on the cleaning beds or distribution reservoirs of the waterworks. As an analytical result of scale on the cleaning beds, we found that it consists of mainly metallic oxides such as $SiO_2$, $Al_2O_3$, $Fe_2O_3$, and MnO. Malic acid, malonic acid, and citric acid showed relatively better solvency on $Al_2O_3$, $Fe_2O_3$, and MnO except $SiO_2$ among various organic acids. Mixed organic acid solutions of malic acid, malonic acid, and citric acid were prepared with certain weight ratios and their solvencies on mixed metal oxides of $Al_2O_3$, $Fe_2O_3$, and MnO were investigated. The experimental results showed that an 10% mixed organic acid solution prepared with weight ratio of malic acid : malonic acid : citric acid = 6 : 2 : 2 were found to have best scale solvency power of about 29%. The formulated cleaning agents with a small amount of nonionic surfactant showed much better solvency on mixed oxides than mixed organic solution alone. Especially, the formulated cleaning agent with 0.2 wt% LA-7 surfactant appeared to have best scale removal efficiency of about 35%. However, the formulated cleaning agent with disinfectants such as NaClO, $H_2O_2$ and $Ca(ClO)_2$ showed poor solvency on mixed oxides. It is inferred that surfactants are able to improve scale removal efficiency due to their capability of emulsification, and disinfectants cause to degrade scale solvency in water because of their oxidation. Based on these basic experimental results, formulated cleaning agents have been prepared with mixed organic acid solution, nonionic surfactants, and disinfectants and successfully applied to removal of scales on the cleaning beds and distribution reservoir at city D waterworks.

Characteristics of Maize Line Treated with Mutagen of γ-Ray at M1 Generation (돌연변이원(突然變異原) γ-선(線)을 처리(處理)한 M1 세대(世代) 옥수수 계통(系統)의 특성(特性))

  • Lee, Hee Bong
    • Korean Journal of Agricultural Science
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    • v.22 no.2
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    • pp.156-162
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    • 1995
  • This study was carried out to select the useful mutants among 20 lines treated with mutagen, gamma ray. These materials were treated with 15, 20, 25 and 30Krads, respectively and sowed at experimental field of College of Agriculture on 27th May, 1995. Items surveyed were germination rate and loss of chlorophyll at seedling stages, abnormal reproductive organs, discordance of flowering times and stem and ear height at ripening stages. The germination rate of lines treated with 15 Krad was different. The germination rate of the IK1, IK2 and Sinki lines were high, while the IK3, A632 and FR140 lines were very low. At same dose level, the germination rate of both IK1/H26 and Puyo synthetic variety were different; the germination rate of the IK1/H26 was high as above 70% at all treatments, while that of the Puyo synthetic variety was very poor at above 20 Krad. Generally stem adn ear height of the IK1/H26 were gradually decreased as the dose of mutagen increased, but there was no difference in stem and ear height of the IK1/H26 when this line was treated with 20Krad. The stem and ear height of lines treated with 15 Krad were shown to be decreased than those of check with non-treatment. The number of tiller of tillering lines were not greatly affected by ${\gamma}$-ray treatment.

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A Study on the Change of Materials and Fabrication Techniques of Stone Figures in Royal Tombs of the Joseon Period - Focusing on Shindobi, Pyo-Seok, and Sang-Seok - (조선시대 왕릉 석물의 재료와 제작 방법 변화에 관한 연구 - 신도비와 표석, 상석을 중심으로 -)

  • Cha, Moonsung
    • Korean Journal of Heritage: History & Science
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    • v.52 no.4
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    • pp.56-77
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    • 2019
  • Bi-Seok is a treasure trove of funeral rites and an important cultural asset that can shed light on the historical and social history of calligraphy, but research of the topic is still insignificant. In particular, research on the production method of Bi-Seok remains an unproven field. The production of Bi-Seok can be roughly divided into ma-jeong (refining stone), sculpture, and the Buk-chil (process of engraving letters) process. This article reveals some facts: First, performing ma-jeong to the Sang-Seok, Honyu-Seok, Bi-seok, which are known to be God's things. This process is needed because of the change in the perception of the Honyu-Seok due to the settlement and propagation of Confucian ceremonial rituals in the times of hardship in 1592 and 1636. As the crafting process of ma-jeong did not remain concrete, it was only possible to examine the manufacturing process of Bi-Seok through its materials and tools. Second, the rapid proliferation of Oh-Seok and Sa-jeo-chwi-yong (purchase of things made by private citizens) in the Yeongjo era has great importance in social and cultural history. When the Gang-Hwa-Seok of the commodity were exhausted, the Oh-Seok that was used by Sadebu (upper civil class) were used in the tomb of Jangneung, which made Oh-Seok popular among people. In particular, the use of Oh-Seok and the Ma-Jeong process could minimize chemical and physical damage. Third, the writing method of the Bi-seok is Buk-chil. After Buk-Chil of Song Si-Yeol was used on King Hyojong's tomb, the Buk-Chil process ( printing the letters on the back of the stone and rubbing them to make letters) became the most popular method in Korea and among other East Asian countries, and the fact that it was institutionalized to this scale was quite impressive. Buk-Chil became more sophisticated by using red ink rather than black ink due to the black color that results from Oh-Seok. Fourth, the writing method changes in the late Joseon Dynasty. Until the time of Yeongjo's regime, when inscribing, the depth of the angle was based on the thickness of the stroke, thus representing the shade. This technique, of course, did not occur at every Pyo-Seok or Shindobi, but was maintained by outstanding artisans belonging to government agencies. Therefore, in order to manufacture Bi-Seok, Suk-seok, YeonJeong, Ma-jeong, Jeong-Gan, ChodoSeoIp, Jung-Cho, Ip-gak, Gyo-Jeong, and Jang-Hwang, a process was needed to make one final product. Although all of these methods serve the same purpose of paying respects and propagandizing the great work of deceased persons, through this analysis, it was possible to see the whole process of Pyo-Seok based upon the division of techniques and the collaboration of the craftsmen.

Influence of Coating Agent and Particle Size on the Soft Magnetic Properties of Fe Based Nano Crystalline Alloy Powder Core (철기(Fe Based) 나노결정질 합금 분말코어의 코팅제 및 입도가 연자기적 특성에 미치는 영향)

  • Jang, S.J.;Choi, Y.J.;Kim, S.W.;Jeon, B.S.;Lee, T.H.;Song, C.B.;Namkung, J.
    • Journal of the Korean Magnetics Society
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    • v.25 no.3
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    • pp.67-73
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    • 2015
  • This is a basic research for improving soft magnetic property of Fe based nano crystalline alloy powder core. The main study is done around characteristics of permeability, core loss, and DC bias depending on amount of insulation coating agent and particle size. First, $Fe_{73.5}Si_{13.5}B_9Nb_3Cu_1$ amorphous alloy ribbon was fabricated by using the planar flow casting (PFC) device. Then, heat treatment and ball milling were done to obtain alloy powder. The amount of polyether imide (PEI) added to it was varied by 0.5, 1.0, 2.0, 2.5 wt% to have compression molding into $16ton/cm^2$. After going through crystalline heat treatment, the made toroidal nano crystalline powder core ($OD12.7mm^*ID7.62mm^*H4.75mm$) had smaller permeability as amount of insulation coating agent decreases. However, it was found out that core loss and DC bias characteristics have been improved. The reason for this results were expected to be because green density of power core decreases as amorphous alloy powder particles become smaller as amount of alloy powder insulation coating agent increases, it was determined that 1 wt% of insulation coating agent is appropriate. Also, for powder core made based on alloy powder size with amount of insulation coating agent fixed at 1 wt%, effective permeability and core loss were outstanding as particle size became bigger. However, characteristics of DC bias became worse as applied DC field increases. This is expected to be due to insulation effect, residual pores, or molding density of powder core resulting from thickness of coating on surface of alloy powder.

Statistical Errors in Papers Published in the Journal of the Korean Society for Therapeutic Radiology and Oncology (대한방사선종양학회지 게재 논문의 통계적 오류 현황)

  • Park, Hee-Chul;Choi, Doo-Ho;Ahn, Song-Vogue;Kang, Jin-Oh;Kim, Eun-Seog;Park, Won;Ahn, Seung-Do;Yang, Dae-Sik;Yun, Hyong-Geun;Chung, Eun-Ji;Chie, Eui-Kyu;Pyo, Hong-Ryull;Hong, Se-Mie
    • Radiation Oncology Journal
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    • v.26 no.4
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    • pp.289-294
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    • 2008
  • Purpose: To improve the quality of the statistical analysis of papers published in the Journal of the Korean Society for Therapeutic Radiology and Oncology (JKOSTRO) by evaluating commonly encountered errors. Materials and Methods: Papers published in the JKOSTRO from January 2006 to December 2007 were reviewed for methodological and statistical validity using a modified version of Ahn's checklist. A statistician reviewed individual papers and evaluated the list items in the checklist for each paper. To avoid the potential assessment error by the statistician who lacks expertise in the field of radiation oncology; the editorial board of the JKOSTRO reviewed each checklist for individual articles. A frequency analysis of the list items was performed using SAS (version 9.0, SAS Institute, NC, USA) software. Results: A total of 73 papers including 5 case reports and 68 original articles were reviewed. Inferential statistics was used in 46 papers. The most commonly adopted statistical methodology was a survival analysis (58.7%). Only 19% of papers were free of statistical errors. Errors of omission were encountered in 34 (50.0%) papers. Errors of commission were encountered in 35 (51.5%) papers. Twenty-one papers (30.9%) had both errors of omission and commission. Conclusion: A variety of statistical errors were encountered in papers published in the JKOSTRO. The current study suggests that a more thorough review of the statistical analysis is needed for manuscripts submitted in the JKOSTRO.

A Study on the Development of an Instrument for Knowledge Contribution Assessment (조직 구성원의 지식기여도 평가 도구 개발에 관한 연구)

  • Na, Mi-Ja;Kym, Hyo-Gun
    • Information Systems Review
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    • v.6 no.2
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    • pp.113-135
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    • 2004
  • This paper defines appraisal items and weights of the items for the purpose of developing an appraisal instrument that objectively measures employee's effectiveness of knowledge contribution. Deductive research is used for the development of appraisal items and delphi method for the development of weights of the items. In the deductive research the term, "effectiveness of knowledge contribution" is first defined. Then knowledge contribution activities are classified as "dimension of explicit contribution" and " dimension of tacit contribution" due to the characteristics of knowledge. Each dimension is divided again by components. The dimension of explicit contribution is divided according to the content of knowledge, and the dimension of tacit contribution is divided according to the extent of tacitness of knowledge contribution. The total components of dimensions are 7. The dimension of explicit contribution is composed of factual knowledge and procedural knowledge. The factual knowledge is made up of "procedural knowledge outcome" and "other factual knowledge". The procedural knowledge is made up of "procedural knowledge manual" and "lessons-learned procedural knowledge". The dimension of tacit contribution is composed of "agency", "model" and "Q&A". The basic framework for measuring 7 components of knowledge contribution is quantitative and qualitative approach. This paper is premised on the assumption that the outcomes of employee's knowledge contribution activities are recorded in the knowledge management systems in order to evaluate them objectively. The appraisal items are defined as follows: at the dimension of explicit contribution, in quantitative approach, "the upload number" or "performance number", and in qualitative approach, other employee's "referred number" and other employee's "content and format satisfaction evaluation"; at the dimension of tacit contribution, "demanded number of performance" After the development of appraisal items by the deductive method, delphi method was used for the analysis of the weights of the items with the total degree of knowledge contribution, 100. This research does not include the standard marks of the appraisal items. It is because when companies apply this appraisal instrument, they could use their own standard appraisal marks of the appraisal items considering their present situations and companies' goals. Through this almost desert-like research about the appraisal instrument of employee's knowledge contribution effectiveness, it proposes a cornerstone in the research field of appraisal instrument, which provides a standard for employee's knowledge contribution appraisal, and appraisal items that make organizational knowledge to be managed more systemically in business sites.

Analysis of Characteristics of Dermatology Outpatients in Korean Medicine Ophthalmology, Otolaryngology & Dermatology at Dunsan Korean Medicine Hospital - From March, 2016 to February, 2019 - (둔산한방병원 한방안이비인후피부과 내원 피부질환 환자 특성 분석 - 2016년 3월부터 2019년 2월까지 -)

  • Kim, Su-Yeong;Jung, Hyun-A
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.33 no.4
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    • pp.16-31
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    • 2020
  • Objectives : This study is designed to analyze outpatients who received medical treatment for skin diseases in ophthalmology & otolaryngology & dermatology clinic of Korean Medical Hospital from March 1st, 2016 to February 28th, 2019. To discover the tendencies of dermatology outpatients and provide the base data for future researches in dermatology patients' characteristics, korean medical treatments on dermatology field, more statistical analysis and establishment of korean medical health care policy. Methods : We classified dermatology outpatients who received treatments in ophthalmology & otolaryngology & dermatology clinic of Korean Medical Hospital from March 1st, 2016 to February 28th, 2019 according to gender, year, age, seasonal, main diagnosis, visit days. The statistical analysis was performed using IBM SPSS 23.0 Results : The results of the analysis on 651 dermatology patients treated in ophthalmology & otolaryngology & dermatology clinic of Dunsan Korean Medical Hospital for the past 3 years are as follows. 1. The number of outpatients who visited ophthalmology & otolaryngology & dermatology clinic of Dunsan Korean Medical Hospital for skin diseases were 651; 286 male(43.9%) and 365 female(56.1%). The number of female patients were approximately 1.27 times higher. 2. The average age of the dermatology outpatients were 37.6. The most frequent visitors turned out to be 20s, and the number of 20s, 30s patients were 267, consisting 41.0% of the whole patients. 3. By examining the change on yearly basis, we noticed that the number of outpatients treated with skin diseases steadily increased with the years. 1) In the analysis of the number of patients classified by gender and year, the number of male and female patients both increased with the years. 2) In the analysis of the number of patients classified by age and year, there were statistically significant difference between two groups. 3) In the analysis of the number of patients classified by season and year, there were statistically significant difference between two groups. 4) In the analysis of the number of patients classified by main diagnosis and year, there were statistically significant difference between two groups. 4. In the analysis of the number of outpatients by seasonal basis, the number of the outpatients visited in summer was the largest by 185(28.4%), followed by winter 181(27.8%), spring 148(22.7%), and the autumn 137(21.0%). 1) In the analysis of the number of patients classified by age and season, there were no statistically significant difference. 2) In the analysis of the number of patients classified by age and season, there were no statistically significant difference. 5. By classifying the outpatients according to main diagnosis, it turned out that there were 40 diagnosis, with eczema the largest followed by urticaria, allergic contact dermatitis, seborrheic dermatitis, and folliculitis. 6. The average number of visit days of dermatology outpatients were 10.24 days, and the number declined steadily with the years. 1) In the analysis of the number of patients classified by gender and visit days, there were no statistically significant difference. 2) In the analysis of the number of patients classified by age and visit days, the visit days of 70s were the shortest and the patients below 20s were longer than the other age groups. Conclusions : By analyzing the outpatients who received medical treatment for skin diseases in ophthalmology & otolaryngology & dermatology clinic of Korean Medical Hospital from March 1st, 2016 to February 28th, 2019 according to gender, year, age, seasonal, main diagnosis, visit days, We drew various meaningful results. The outpatients with skin diseases increased steadily by the years, and patients visited in winter especially shown the outstanding increase. And though the number of female patients were larger than male, the increase was bigger in male patients. We hope that this results would provide useful resources for future researches in dermatology patients'characteristics, korean medical treatment and establishment of korean medical health care policy.

A Comparison of the Emotional Characteristics between the Gifted and the General Students of the Elementary School - Focus on Modern 'Hyo' Concept Behavioral Factors - (초등 영재학생과 일반학생의 정의적 특성 비교 - 현대적 효 개념의 행동 요인 중심으로 -)

  • Park, Kyung-Bin;Lee, Seok-Lae
    • Journal of Gifted/Talented Education
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    • v.19 no.3
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    • pp.503-527
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    • 2009
  • The purpose of this research is to compare and analyze differences in modern 'Hyo' concepts and behaviors between the gifted and the general students of the elementary school. In this study, two groups(the gifted and the general students of the elementary school) were compared, in grade, birth-order, family members, education and religion factors in family, to seek for a better way to teach the Korean gifted students. The results are, as follows. First, the gifted had higher 'Hyo' concepts than the general students, because developments of the gifted in the field of intellect, emotion and will are faster than the general. The gifted had many interests in values and moral decisions. There are no meaningful differences between boys and girls in the gifted group. But in the general group, girls have higher 'Hyo' concepts than boys. This is because girls emotional developments are faster than boys. Second, in the gifted group, 5th graders have higher 'Hyo' concepts than 6th graders. On the other hand, in the general group, there are no meaningful differences between 5th graders and 6th graders. Third, there were no differences between the groups(gifted/general) by birth-order, family members and having religions or not. However, the comparison between nuclear families and large families shows that Korean traditional ethics - 'Hyo' is still in existence as a basic concept in the family, in spite of the changing family size and unit. In addition, in the family with a religion, the' Hyo' concept is revealed stronger than the other group. This is caused by the power of commanding love and affection which are emphasized through religions. From the results of this research, the gifted students of the elementary school have high consciousness concerning 'Hyo' concepts and behaviors. It is very essential for them to improve their 'Hyo' concepts until adulthood. Therefore, teachers and parents should pay more attention to help them improve their senses of Korean traditional morality - 'Hyo'.