• Title/Summary/Keyword: 품질관리대상

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A Study on the Spectacles Wearing State of High School Students (고등학생들의 안경착용에 관한 연구)

  • Doo, Ha-Young;Sim, Sang-Hyun
    • Journal of Korean Ophthalmic Optics Society
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    • v.5 no.1
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    • pp.107-116
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    • 2000
  • This study is of investigation of refraction error, spectacles and contact lenses wearing state, visual acuity test, ophthalmologic common sense and vision care, using questionnaire study for 850 male and female high school students in Kunsan and Chongup City, Cheolla North Province. The results are as follows: 1. Among the 823 answerers, emmetropia is 18%, myopia is 55.1%, and hyperopia is 7%, respectively. 2. Among the 837 answerers, 381 students(45.5%) wear spectacles or contact lenses. Among the 381 students who wear spectacles or contact lenses, 78% wear only spectacles, 4% wear only contact lenses and 18% wears spectacles sometimes or contact lenses sometimes. 3. The places where the answerers had visual acuity test to wear spectacles or contact lenses are optical shop(64.7%), hospital(28.3%), unchecked(4.2%) and the others(2.7%). The places where the answerers had visual acuity test to change their spectacles or contact lenses are optical shop(82%), hospital(28.3%), unchecked(6.6%) and the others(1.9%). 4. As for the period of visual acuity test, from 6 months to one year is 54.1%, within 6 months is 9.2%, from one year to two years is 29.5%, and more than two years is 7.2%. 5. The contact lens wearers purchased their contact lenses at optical shops(94%) and at hospital(6%). 6. The reasons why they like wearing contact lenses are their appearance(51.2%), convenience in physical excercise(23.l%), lighter weight than spectacles(9.8%) and the others(15.7%). 7. As for the spectacles frame they like, plastic frame is 24.4%, gold or silver plated frame is 43.4%, coloured frame is 32.1%. 8. As for the considerations in choosing spectacles frame, their design is 37%, their quality is 36%, their price is 14.7% and their brand is 12.5%. 9. As for the period for changing spectacles, 10.5% is within 6 months, 57.3% is 6months to 1 year, 22.4% is 1 year to 2 months and 9.6% is more than 2 years. 10. There is a false fact, in Korea, that even though one has his poor eyesight, not wearing custom is helpful for the eyesight recovery. As for their conviction of the false fact, 10.5% of the answerers have 100% conviction, 22.5% of them have 22.5% conviction, 49.5% of them have 50% conviction and 17.5% of them don't have any conviction. 11. 48.5% of the answerers are interested in their vision care while 51.5% of them are not interested at all. As for the way of vision care, the vision-care way to keep enough distant when they are watching TV, when they are using computers and when they are reading, is 49% while the vision-care way such as hypogastric breathing or eye massage is 11%. And alimentotherapy is 4% and the rest who are not interested in vision care is 36%. 12. When they come to an age, the students who want vision correction operation are 45.9% while the students who do not want it are 27%. The students who do not have any idea about the operation are 27.1%

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Clothing Purchase Behavior of Adolescents by the Consumer Awareness (청소년의 소비자 의식과 의복구매행동)

  • 김종희;조현주
    • Journal of Korean Home Economics Education Association
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    • v.15 no.2
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    • pp.67-78
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    • 2003
  • To investigate the consumer awareness and clothing purchase behavior of adolescents, questionnaire was administered to 639 middle and high school students in Daegu. The results were as follows. 1. The consumer awareness of adolescents was analyzed to 4 factors. consciousness of right. consumer information, brand-orientedness and responsibility. Respondents were clustered into three groups : utility-oriented group, brand-oriented group, and consumerism-oriented group. 2. Respondents bought their clothes at specialty stores primarily. They used ´products´, ´family's or friends advices´, and ´purchase experiences´ as information sources. The important criteria for selecting clothes were ´design´, ´price´, and ´suitability´ for oneself. Dissatisfactions after purchasing clothes were with ´price´, ´service´, ´sewing´, and ´size´. The complaining behaviors which respondents did mainly were ´telling friends about dissatisfaction with their purchased clothes´, ´asking for change dissatisfying products or asking for refund´ and ´asking for mending´. 3. Information sources were categorized into 3 factors: ´neutral information source´, ´personal information source´ and ´commercial information source´. Criteria for selecting clothes were factor-analyzed into ´harmony´, ´fashion´ and ´management of clothes´. ´The factors of dissatisfactions with purchased clothes were ´appearance´, ´quality´ and ´service´. 4. The differences by the consumer awareness in clothing purchase behaviors among consumer groups : In information sources. criteria for selecting clothes, complaining behaviors. purchasing places. three consumer groups were different significantly.

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Calculation of Soil Moisture and Evapotranspiration of KLDAS applying Ground-Observed Meteorological Data (지상관측 기상자료를 적용한 KLDAS(Korea Land Data Assimilation System)의 토양수분·증발산량 산출)

  • Park, Gwangha;Kye, Changwoo;Lee, Kyungtae;Yu, Wansik;Hwang, Eui-ho;Kang, Dohyuk
    • Korean Journal of Remote Sensing
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    • v.37 no.6_1
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    • pp.1611-1623
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    • 2021
  • Thisstudy demonstratessoil moisture and evapotranspiration performance using Korea Land Data Assimilation System (KLDAS) under Korea Land Information System (KLIS). Spin-up was repeated 8 times in 2018. In addition, low-resolution and high-resolution meteorological data were generated using meteorological data observed by Korea Meteorological Administration (KMA), Rural Development Administration (RDA), Korea Rural Community Corporation (KRC), Korea Hydro & Nuclear Power Co.,Ltd. (KHNP), Korea Water Resources Corporation (K-water), and Ministry of Environment (ME), and applied to KLDAS. And, to confirm the degree of accuracy improvement of Korea Low spatial resolution (hereafter, K-Low; 0.125°) and Korea High spatial resolution (hereafter, K-High; 0.01°), soil moisture and evapotranspiration to which Modern-Era Retrospective analysis for Research and Applications, version 2 (MERRA-2) and ASOS-Spatial (ASOS-S) used in the previous study were applied were evaluated together. As a result, optimization of the initial boundary condition requires 2 time (58 point), 3 time (6 point), and 6 time (3 point) spin-up for soil moisture. In the case of evapotranspiration, 1 time (58 point) and 2 time (58 point) spin-ups are required. In the case of soil moisture to which MERRA-2, ASOS-S, K-Low, and K-High were applied, the mean of R2 were 0.615, 0.601, 0.594, and 0.664, respectively, and in the case of evapotranspiration, the mean of R2 were 0.531, 0.495, 0.656, and 0.677, respectively, indicating the accuracy of K-High was rated as the highest. The accuracy of KLDAS can be improved by securing a large number of ground observation data through the results of this study and generating high-resolution grid-type meteorological data. However, if the meteorological condition at each point is not sufficiently taken into account when converting the point data into a grid, the accuracy is rather lowered. For a further study, it is expected that higher quality data can be produced by generating and applying grid-type meteorological data using the parameter setting of IDW or other interpolation techniques.

Analysis of Evaluator's Role and Capability for Institution Accreditation Evaluation of NCS-based Vocational Competency Development Training (NCS 기반 직업능력개발훈련 기관인증평가를 위한 평가자의 역할과 역량 분석)

  • Park, Ji-Young;Lee, Hee-Su
    • Journal of vocational education research
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    • v.35 no.4
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    • pp.131-153
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    • 2016
  • The purpose of this study was to derive evaluator's role and capability for institution accreditation evaluation of NCS-based vocational competency development training. This study attempted to explore in various ways evaluator's minute roles using Delphi method, and to derive knowledge, skill, attitude and integrity needed to verify the validity. To the end, this study conducted the Delphi research for over three rounds by selecting education training professionals and review evaluation professions as professional panels. From the results, roles of evaluators were defined as the total eight items including operator, moderator-mediator, cooperator, analyzer, verifier, institution evaluator, institution consultant, and learner, and the derived capabilities with respect to each role were 25 items in total. The area of knowledge included four items of capabilities such as HRD knowledge, NCS knowledge, knowledge of vocational competency development training, and knowledge of training institution accreditation evaluation, and the area of skill comprised fourteen items of capabilities such as conflict management ability, interpersonal relation ability, word processing ability, problem-solving ability, analysis ability, pre-preparation ability, time management ability, decision making ability, information comprehension and utilization ability, comprehensive thinking ability, understanding ability of vocational competency development training institutions, communication ability, feedback ability, and core understanding ability. The area of attitude was summarized with the seven items in total including subjectivity and fairness, service mind, sense of calling, ethics, self-development, responsibility, and teamwork. The knowledge, skill and attitude derived from the results of this study may be utilized to design and provide education programs conducive to qualitative and systematic accreditation and assessment to evaluators equipped with essential prerequisites. It is finally expected that this study will be helpful for designing module education programs by ability and for managing evaluator's quality in order to perform pre-service education and in-service education according to evaluator's experience and role.

Introduction of the Best Practices in the Pakistan Gulpur HEPP (파키스탄 Gulpur 수력발전 현장의 Best Practices 소개)

  • JANG, Ock Jae;HONG, Won Pyo;CHAE, Hee Moon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.216-217
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    • 2022
  • Gulpur 수력발전 프로젝트는 전력난을 겪고 있는 파키스탄에 102 MW 규모의 수력발전소를 건설하여 30년 동안 운영 관리한 후 파키스탄 정부로 양도하는 IPP(Independent Power Producing) 형식의 투자사업이다. 남동발전과 DL E&C, 롯데건설이 Sponsor로서 출자한 자본금과, ADB, IFC, K-EXIM 등의 대주단로부터의 차입금을 재원으로 하여 소요 사업비를 조달하고 사업을 개발하였다. DL E&C와 롯데건설이 EPC(Engineering, Procurement, Construction)를 수행하였고, 이산이 Design consultant의 역할을 수행하였다. Gulpur 수력발전 프로젝트의 발전형식은 수로식(run-of-river)으로 201 m3/s의 발전유량과 102 MW의 발전 시설용량을 이용하여 연평균예상발전량은 398 GWh이다. 주요 구조물로는 설계 재현빈도 1년의 유수전환시설(가물막이댐 & 가배수터널)과 콘크리트 중력식댐(H 67 m, L 205 m), 도수터널(D 6.7 m, L 215 m, 2기), 옥외형 발전소 (H 51 m, W 60 m, L 38 m, Kaplan 2기)가 있으며, 2015년 10월 착공하여 2020년 3월 상업발전을 시작하였다. 본 프로젝트는 DL E&C의 첫 번째 EPC 해외수력발전 프로젝트이다. 따라서 프로젝트의 성공적 수행을 위한 경제적 설계, 시공의 효율성 및 안정성 확보 등을 위하여 많은 연구를 수행하는 과정에서 다양한 기술 개선을 이룰 수 있었다. 본고에서는 Gulpur 프로젝트를 통하여 도출된 성공 사례들을 소개 및 공유하고자 한다. 첫 번째로 콘크리트 중력식댐 시공을 위한 유수전환시설의 최적 설계빈도를 산정하였다. 일반적으로 유수전환시설의 규모는 설계기준에 제시된 설계 재현빈도를 이용하는데, 해외 설계기준에서는 10년, 국내 설계기준에서는 1~2년으로 다르게 제시되어 있는 문제점이 있다. 유수전환시설의 규모는 프로젝트의 경제성에 큰 영향을 미치기 때문에 최적 설계빈도의 결정이 필요하며, 위험도분석기법(Risk Analysis)과 기대화폐가치법(Expected Monetary Value)을 이용하여 유수전환시설의 최적 설계 재현빈도와 이에 영향을 미치는 인자를 분석하였다. 위험도는 몬테카를로 시뮬레이션으로 산정된 가물막이댐 파괴확률과 재현빈도를 이용하여 산정된 가물막이댐 월류확률을 고려하였으며, 비용 및 피해액으로는 유수전환시설의 공사비, 가물막이댐 파괴시의 재건설비용과 지체보상금, 가물막이댐 월류시의 복구비용을 고려하였다. 이에 대한 연구결과로, 유수전환시설의 사용기간과 월류시의 복구비용이 유수전환시설의 설계 재현기간 결정에 가장 큰 영향을 미치는 것으로 나타났고, 특히 월류시의 복구비용이 작을수록 낮은 설계 재현빈도를 선택하는 것이 타당한 것으로 나타났다. 예를 들어, 유수전환시설의 사용기간이 3 ~ 5년, 복구비용이 0.5 ~ 1.0 mil USD 이하인 조건에서 가물막이시설의 최적 설계빈도는 1년 ~ 2년인 것으로 나타났다. 또한, 유수전환시설의 사용기간은 본댐의 규모와 시공기간 등을 고려하여 결정되는 사항으로 설계자가 임의 조정할 수 없지만, 복구비용은 시공 관리자에 따라 결정되는 부분으로, 적극적 홍수 피해 저감 및 복구방안을 마련하는 것이 프로젝트의 경제성을 향상시킬 수 있다는 것을 알 수 있었다. 두 번째로 프로젝트의 경제성 향상, 홍수기 댐 시공시의 안전성 확보를 위하여 홍수 조기경보시스템(Early Warning System)을 개발 및 활용하였다. 수로식(Run-of-river) 수력발전댐은 대부분 산악지역에 위치하기 때문에 국지성 강우 및 급한 지형 경사로 인하여 돌발홍수(flash flood)의 발생 가능성이 높다. 따라서 시공 중 홍수(월류) 발생을 미리 감지하고 현장에 전파할 수 있는, 수로식(Run-of-river) 수력발전댐 현장을 위한 홍수 조기경보시스템이 필요하며, 이를 리스크 인식, 모니터링 및 경보, 전파 및 연락, 반응 능력 향상의 4가지 부분으로 나누어 구축하였다. 리스크 인식 부분에서는 가물막이댐 월류 발생 상황에 대한 위험도, 취약성, 리스크를 제시하였으며, 모니터링 및 경보 부분에서는 상류 측정수위에서 유도된 현장 예상수위와 실제 현장 측정 수위를 대상으로 경보홍수위와 위험홍수위로 나누어 관리하였다. 전파 및 연락 부분에서는 현장 시공 조직을 활용하여 홍수시를 대비한 비상연락체계도(Emergency communication flow chart)를 운영하였으며, 반응 능력 향상을 위해 비상연락체계도의 팀별 Action plan을 상세화 하였다. 세 번째로 현장의 지질특성과 50여 차례 발파시험으로 현장 고유의 발파진동감쇄곡선을 도출하였으며, 이를 통해 현장의 시공성과 콘크리트 품질 확보를 동시에 달성할 수 있는 방안을 제시하였다. 콘크리트댐 공사에서는 제한된 공기 내에 공사를 완료하기 위해 사면부 굴착과 콘크리트 타설이 동시에 수행될 수밖에 없는 문제점을 가지고 있다. 그러나 신규 콘크리트 타설면 근처에서 발파를 수행하는 경우 발파로 발생되는 탄성파가 일정 수준을 초과하게 되면, 콘크리트 양생에 영향을 주게 된다. 따라서 다수의 현장 발파시험을 통해 발파거리와 최대진동속도의 상관관계 즉, 발파진동감쇄곡선을 도출함으로써 현장의 발파진동특성을 도출할 수 있었다. 또한, 기존 연구 논문들을 통해 콘크리트 재령기간 별 안전진동속도를 선정하고, 해당 안전진동속도를 초과하지 않는 범위에서 콘크리트 타설면과 발파위치의 거리에 따라 1회 발파 가능한 장약량을 산정하여 적용하였다. 이와 같은 체계적인 접근을 통해 콘크리트 타설과 발파 작업 동시 수행에 대한 논란을 해소할 수 있었다.

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Effects on cooperative spirit of a cohort by instruction types of Taekwondo (태권도 지도자의 지도유형이 집단응집력에 미치는 영향)

  • Jeong, Chan-Sam
    • Korean Security Journal
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    • no.13
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    • pp.471-485
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    • 2007
  • This study is performed to find out what type instructions are produced to players by coaches and what effects are resulted in cooperative spirit of the concerned group. Furthermore the study has its aims at advancing instructors' skills by using finding of it. The study used 'SPSS 11.0 FOR WINDOW - Statistical Package' to analyze the collected samples and dealt with data of 174 individuals. Statistical analysis of the research for hypothesis verification was about frequency, trust level, mutual relationship, variables, and T-verification. The meaningful level for any result was ranged within 95%(p< .05), 99%(p<.01). The finding are as follows. Effects on pleasure, one of elements of team spirits taken by instructor's training style are analyzed as follows. It was proved to be meaningful in relation with a series of activities like training, democratic, social, compensatory aspects and showed also considerable relation with power based behaviors. That says, players are found to enjoy high pleasure when social and bureaucratic behaviors of instructors are very energetic. In addition to that, training, democratic, and compensatory activities didn't show any meaningful effect. Team spirit was found to play a main role between instructor's behaviors and training, democratic, social rewarding activities. Democratic and social acts influence on team spirit. Looking into the detailed aspects, team spirit was resulted very high in the individuals with low democratic mind and was shown high group spirit by groups with high sociable activities. Teamworks was found to be affected by relation between instructor's acts and training, democratic, social and compensatory aspects and it showed meaningful relations with training, social, bureaucratic behaviors. Low degree of training and bureaucratic activities are found to prefer for power team spirit, and high social activities led a strong teamworks. Group binding spirit was influenced by training, democratic, social compensatory, bureaucratic behaviors and it showed to give effects on democratic, social, and bureaucratic activities of instructors. Low degree of democratic and bureaucratic behaviors are found to produce strong team spirit. In contrast with that, strong social activities was found to be motive of powerful team spirit. Value of team spirit was found to play a main role between instructor's behaviors and training, democratic, social, rewarding activities. It didn't show any meaningful effect on behavior of instructors.

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Studies on Storage Characteristics of Tofu with Herb (허브첨가 두부의 저장 특성)

  • Jeon, Mi-Kyung;Kim, Mee-Ra
    • Korean journal of food and cookery science
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    • v.22 no.3 s.93
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    • pp.307-313
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    • 2006
  • Tofu was prepared with various herbs (green tea, rosemary, lavender and thyme) and the tofu quality was investigated during storage. In the measurement of tofu color, the L and b values increased during storage period. Especially, the b value was very high at 8 days after storage. The pH value of tofu increased until 6 days of storage, but then decreased. The turbidity gradually increased until 6 days of storage and rapidly increased at 8 days of storage. The microorganism count of herb tofu was lower an that of control tofu during storage. Especially green tea tofu showed the lowest psychrotrophic microorganism count as $1.3{\times}10^8\;CFU/g$. In addition, lavender tofu showed the lowest aerobic mesophilic microorganism count $(2.0{\times}10^7\;CFU/g)$ at 8 days of storage. In texture analysis, hardness and chewiness of herb tofu increased with increasing storage period. Springiness increased to 2 or 4 days of storage but decreased after 6 or 8 days. Therefore, herb tofu is expected to have good quality physiologically as well as microbiologically.

The Impact of O4O Selection Attributes on Customer Satisfaction and Loyalty: Focusing on the Case of Fresh Hema in China (O4O 선택속성이 고객만족도 및 고객충성도에 미치는 영향: 중국 허마셴셩 사례를 중심으로)

  • Cui, Chengguo;Yang, Sung-Byung
    • Knowledge Management Research
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    • v.21 no.3
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    • pp.249-269
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    • 2020
  • Recently, as the online market has matured, it is facing many problems to prevent the growth. The most common problem is the homogenization of online products, which fails to increase the number of customers any more. Moreover, although the portion of the online market has increased significantly, it now becomes essential to expand offline for further development. In response, many online firms have recently sought to expand their businesses and marketing channels by securing offline spaces that can complement the limitations of online platforms, on top of their existing advantages of online channels. Based on their competitive advantage in terms of analyzing large volumes of customer data utilizing information technologies (e.g., big data and artificial intelligence), they are reinforcing their offline influence as well through this online for offline (O4O) business model. On the other hand, most of the existing research has primarily focused on online to offline (O2O) business model, and there is still a lack of research on O4O business models, which have been actively attempted in various industrial fields in recent years. Since a few of O4O-related studies have been conducted only in an experience marketing setting following a case study method, it is critical to conduct an empirical study on O4O selection attributes and their impact on customer satisfaction and loyalty. Therefore, focusing on China's representative O4O business model, 'Fresh Hema,' this study attempts to identify some key selection attributes specialized for O4O services from the customers' viewpoint and examine the impact of these attributes on customer satisfaction and loyalty. The results of the structural equation modeling (SEM) with 300 O4O (Fresh Hema) experienced customers, reveal that, out of seven O4O selection attributes, four (mobile app quality, mobile payment, product quality, and store facilities) have an impact on customer satisfaction, which also leads to customer loyalty (reuse intention, recommendation intention, and brand attachment). This study would help managers in an O4O area well adapt to rapidly changing customer needs and provide them with some guidelines for enhancing both customer satisfaction and loyalty by allocating more resources to more significant selection attributes, rather than less significant ones.

Long-term Evaluation of Muscle Quality of the Olive Flounder, Paralichthys olivaceus, Fed with Extruded Pellet (배합사료로 장기간 사육된 넙치의 육질평가)

  • Kim, Kang-Woong;Kang, Yong-Jin;Kim, Kyoung-Duck;Choi, Se-Min;Lee, Jong-Yun;MoonLee, Hae-Young;Bai, Sung-Chul C.
    • Journal of Aquaculture
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    • v.20 no.1
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    • pp.51-55
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    • 2007
  • This study was conducted to evaluate the muscle quality of the olive flounder fed on extruded pellet (EP) diets compared with a raw fish moist pellet (MP) diet for olive flounder, Paralichthys olivaceus in a commercial scale for a year. The sensory and physical qualities and palatable compounds were compared for evaluation of muscle quality in fish. Four diets were formulated for this experiment: two experimental EP diets (EP 1 and 2), one commercial EP diet (CEP) and MP diet. Crude lipid of fish fed EP1 and EP2 was significantly higher (P<0.05) than that of fish fed CEP, but not significantly different from that of fish fed MP (P>0.05). In the palatable compounds, the free amino acids composition were much alike in that of all the diets. Proline, glycine and alanine from fish fed diet EPs were the most abundant compound among amino acid compositions. There was little difference in the free amino acid compositions of all flounder from localities and the growing conditions between wild and cultured fishes. Taurine of fish fed EP1 was dominantly high over that of fish fed EP2, CEP and MP. In all nucleotides and their related compounds, ATP and IMP from fish fed EP diets were higher (P<0.05) than those of fish fed MP. In the sensory score, overall-acceptability of fish fed EP2 were significantly higher (P<0.05) than that of fish fed EP1, CEP and MP. Hardness of physical properties from fish fed EP2 was significantly higher (P<0.05) than those of fish fed CEP (P<0.01). These results strongly suggest that diets EP could be developed to replace MP diet for the grow-out stage of olive flounder without adverse effect on growth performance.

THE CHANGE OF THE CONFIGURATION OF HYDROXYAPATITE CRYSTALS IN ENAMEL BY CHANGES OF PH AND DEGREE OF SATURATION OF LACTIC ACID BUFFER SOLUTION (유산 완충용액의 pH 및 포화도 변화에 따른 법랑질 내 수산화인회석 결정 형태의 변화)

  • Chon, Young-Eui;Jung, Il-Young;Roh, Bung-Duk;Lee, Chan-Young
    • Restorative Dentistry and Endodontics
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    • v.32 no.6
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    • pp.498-513
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    • 2007
  • Since it was reported that incipient enamel caries can be recovered, previous studies have quantitatively evaluated that enamel artificial caries have been, remineralized with fluoride showing simultaneously the increase of width of surface layer and the decrease of width of the body of legion. There is, however, little report which showed that remineralization could occur without fluoride. In addition, the observations on the change of hydroxyapatite crystals also have been scarcely seen. In this study, enamel caries in intact premolars or molars was induced by using lactic acidulated buffering solutions over 2 days. Then decalcified specimens were remineralized by seven groups of solutions using different degree of saturation(0.212, 0.239, 0.301, 0.355) and different pH(5.0, 5.5, 6.0) over 10 days. A qualitative comparison to changes of hydroxyapatite crystals after fracturing teeth was made under SEM(scanning electron microscopy) and AFM(atomic force microscopy). The results were as follows: 1. The size of hydroxyapatite crystals in demineralized area was smaller than the normal ones. While the space among crystals was expanded, it was observed that crystals are arranged irregularly. 2. In remineralized enamel area, the enlarged crystals with various shape were observed when the crystals were fused and new small crystals in intercrystalline spaces were deposited. 3. Group 3 and 4 with higher degree of saturation at same pH showed the formation of large clusters by aggregation of small crystals from the surface layer to the lesion body than group 1 and 2 with relatively low degree of saturation at same pH did. Especially group 4 showed complete remineralization to the body of lesions. Group 5 and 6 with lower pH at similar degree of saturation showed remineralization to the body of lesions while group 7 didn't show it. Unlike in Group 3 and 4, Group 5 and 6 showed that each particle was densely distributed with clear appearance rather than crystals form clusters together.