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Development of Goals Tentative of Dental Health Education in the Elementary Schools (초등학교 구강보건교육의 목표 시안개발)

  • Lee, Hyung-Sook
    • Journal of Korean society of Dental Hygiene
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    • v.2 no.1
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    • pp.43-61
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    • 2002
  • The purpose of this study was focus on development of educational objectives by using oral health education in the elementary school from now on. Based on the results of analysis compared with a model of educational objectives and contents by reflecting the programs for analysis were the oral health education programs of the Ministry of health and social Affairs in Korea, and the programs of two states in u.s. in order to construct goals and contents of oral health education in school. The results in this study can be arranged as follows: First, an analysis on the educational objectives of dental health education program resulted that, from a viewpoint of Bloom's taxonomy of educational objectives, in case of domestic, most learning objectives expressed in the handbook of Ministry of Health and social Welfare were given too much emphasis to the cognitive domain of 37 an items in all. Affective domain were appeared the lack of balance of the development domain. Second, the result of analysis for the programs of two states of America, the cognitive domain were the most abundant of 48 an items in all, and were not significantly different to those of Korea in the form of objectives domain or statement. However a big different was shown that they organized the same objectives domain as a pattern of repeating and deepening at every grade. Third, in this study, 10 educational objectives of dental health education were established, based on the result of analyzing those existing educational programs as central figure. Those are oral cavity, brushing, nutrition of teeth, fluoride, flossing, teeth injury, dental decay, periodontal disease, malocclusion, routine dental visits. And general objectives and specific objectives of each learning area were stated and arranged grade by grade.

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Energy separation and carrier-phonon scattering in CdZnTe/ZnTe quantum dots on Si substrate

  • Man, Min-Tan;Lee, Hong-Seok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2015.08a
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    • pp.191.2-191.2
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    • 2015
  • Details of carrier dynamics in self-assembled quantum dots (QDs) with a particular attention to nonradiative processes are not only interesting for fundamental physics, but it is also relevant to performance of optoelectronic devices and the exploitation of nanocrystals in practical applications. In general, the possible processes in such systems can be considered as radiative relaxation, carrier transfer between dots of different dimensions, Auger nonradiactive scattering, thermal escape from the dot, and trapping in surface and/or defects states. Authors of recent studies have proposed a mechanism for the carrier dynamics of time-resolved photoluminescence CdTe (a type II-VI QDs) systems. This mechanism involves the activation of phonons mediated by electron-phonon interactions. Confinement of both electrons and holes is strongly dependent on the thermal escape process, which can include multi-longitudinal optical phonon absorption resulting from carriers trapped in QD surface defects. Furthermore, the discrete quantized energies in the QD density of states (1S, 2S, 1P, etc.) arise mainly from ${\delta}$-functions in the QDs, which are related to different orbitals. Multiple discrete transitions between well separated energy states may play a critical role in carrier dynamics at low temperature when the thermal escape processes is not available. The decay time in QD structures slightly increases with temperature due to the redistribution of the QDs into discrete levels. Among II-VI QDs, wide-gap CdZnTe QD structures characterized by large excitonic binding energies are of great interest because of their potential use in optoelectronic devices that operate in the green spectral range. Furthermore, CdZnTe layers have emerged as excellent candidates for possible fabrication of ferroelectric non-volatile flash memory. In this study, we investigated the optical properties of CdZnTe/ZnTe QDs on Si substrate grown using molecular beam epitaxy. Time-resolved and temperature-dependent PL measurements were carried out in order to investigate the temperature-dependent carrier dynamics and the activation energy of CdZnTe/ZnTe QDs on Si substrate.

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A Parabolic Approximation Model for Wave Deformation Combined Refraction, Diffraction, and Breaking (파랑(波浪)의 굴절(屈折), 회절(回折) 및 쇄파변형(碎波變形)에 관한 포물형근사모형(抛物形近似模型))

  • Lee, Dong Soo;Lee, Jong Sup;Park, II Heum
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.3
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    • pp.619-633
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    • 1994
  • A wave deformation model for general purpose combined refraction, diffraction, and breaking is developed in the shallow water. A parabolic approximation equation considered a higher order diffraction term is derived from the previous mild slope equation. A wave energy dissipation term due to bottom friction and breaking is introduced from the turbulence model. The Crank-Nicoloson implicit scheme is used in the numerical calculation, then the solutions are compared with the various hydraulic experiment data in the circular, the elliptic shoal, and the surf zone. The wave height decay in the surf zone is sensitively affected by the incident wave steepness, and the wave height variation around the elliptic shoal is well explained by the non-linear dispersion relation and the wave energy dissipation term. The model is also applied to a field coastal area and reasonable results are obtained.

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Level of Agreement and Factors Associated With Discrepancies Between Nationwide Medical History Questionnaires and Hospital Claims Data

  • Kim, Yeon-Yong;Park, Jong Heon;Kang, Hee-Jin;Lee, Eun Joo;Ha, Seongjun;Shin, Soon-Ae
    • Journal of Preventive Medicine and Public Health
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    • v.50 no.5
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    • pp.294-302
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    • 2017
  • Objectives: The objectives of this study were to investigate the agreement between medical history questionnaire data and claims data and to identify the factors that were associated with discrepancies between these data types. Methods: Data from self-reported questionnaires that assessed an individual's history of hypertension, diabetes mellitus, dyslipidemia, stroke, heart disease, and pulmonary tuberculosis were collected from a general health screening database for 2014. Data for these diseases were collected from a healthcare utilization claims database between 2009 and 2014. Overall agreement, sensitivity, specificity, and kappa values were calculated. Multiple logistic regression analysis was performed to identify factors associated with discrepancies and was adjusted for age, gender, insurance type, insurance contribution, residential area, and comorbidities. Results: Agreement was highest between questionnaire data and claims data based on primary codes up to 1 year before the completion of self-reported questionnaires and was lowest for claims data based on primary and secondary codes up to 5 years before the completion of self-reported questionnaires. When comparing data based on primary codes up to 1 year before the completion of selfreported questionnaires, the overall agreement, sensitivity, specificity, and kappa values ranged from 93.2 to 98.8%, 26.2 to 84.3%, 95.7 to 99.6%, and 0.09 to 0.78, respectively. Agreement was excellent for hypertension and diabetes, fair to good for stroke and heart disease, and poor for pulmonary tuberculosis and dyslipidemia. Women, younger individuals, and employed individuals were most likely to under-report disease. Conclusions: Detailed patient characteristics that had an impact on information bias were identified through the differing levels of agreement.

Affecting factors to oral scaling experience of the part worker (일부 직장인의 구강건강상식 및 스케일링에 대한 인식도)

  • Cheon, Seok-Yeon;Won, Bok-Yeon
    • Journal of Korean society of Dental Hygiene
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    • v.11 no.1
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    • pp.1-12
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    • 2011
  • Objectives : This study was to investigate into company workers' oral scaling related factors and enhance a rate of oral scaling. Methods : From August 2010, self-administered questionnaires of the about general question items, oral health relation factors, knowledge of periodontal disease for oral scaling performed, in 267 people worker objects. Results : The followings are the findingd of this research. First, Oral scaling experiences were responded by 205 people(76.8%). Among those prevention the case which enforces with a goal periodically 6 month period 7.3% and the period of 1 years is 28.8%, be most inconvenient is cold(50.7%), with motive is dentistry visits inducement for tooth therapy which 51.2%, Non experience in oral scaling was responded by 62 people(23.2%), 45.2% of whom answered they had no necessity for such treatment. Second, Knowledge of periodontal disease is 'dental calculus and stain loses toothbrush quality did eagerly' incorrect one right answer ratio is highest with 86.5%, 'Becoming the adult being made to draw out tooth is periodontitis than decay' was incorrect one right answer rate was lowest with 62.9%. Third, The workers' sex, service field, one month average income, Currently the oral inconvenient presence, oral health Interest degree, tooth brushing method, knowledge of periodontitis have a significant effect on their oral scaling experience. Conclusions : When seeing with result of above, it is necessary of the oral scaling widely with the method which is various includes a mass communication by causing the changes in the perception of oral scaling. The dental hygienist is inconvenience from oral scaling experience have interest when is possible the patient comfortably, in order could be operated, endeavors demanded.

Flow structures around rectangular cylinder in the vicinity of a wall

  • Derakhshandeh, J.F.;Alam, Md. Mahbub
    • Wind and Structures
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    • v.26 no.5
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    • pp.293-304
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    • 2018
  • A numerical study is conducted on the flow characteristics of a rectangular cylinder (chord-to-width ratio C/W = 2 - 10) mounted close to a rigid wall at gap-to-width ratios G/W = 0.25 - 6.25. The effects of G/W and C/W on the Strouhal number, vortex structure, and time-mean drag and lift forces are examined. The results reveal that both G/W and C/W have strong influences on vortex structure, which significantly affects the forces on the cylinder. An increase in G/W leads to four different flow regimes, namely no vortex street flow (G/W < 0.75), single-row vortex street flow ($0.75{\leq}G/W{\leq}1.25$), inverted two-row vortex street flow ($1.25<G/W{\leq}2.5$), and two-row vortex street flow (G/W > 2.5). Both Strouhal number and time-mean drag are more sensitive to C/W than to G/W. For a given G/W, Strouhal number grows with C/W while time-mean drag decays with C/W, the growth and decay being large between C/W = 2 and 4. The time-mean drag is largest in the single-row vortex street regime, contributed by a large pressure on the front surface, regardless of C/W. A higher C/W, in general, leads to a higher time-mean lift. The maximum time-mean lift occurs for C/W = 10 at G/W = 0.75, while the minimum time-mean lift appears for C/W = 2 at the same G/W. The impact of C/W on the time-mean lift is more substantial in single-row vortex regime. The effect of G/W on the time-mean lift is larger at a larger C/W.

Development of ACBIO: A Biosphere Template Using AMBER for a Potential Radioactive Waste Repository (AMBER를 이용한 방사성폐기물처분장 생태계 평가 템플릿 ACBIO 개발)

  • Lee Youn-Myoung;Hwang Yongsoo;Kang Chul-Hyung;Hahn Pil-Soo
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.3 no.3
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    • pp.213-229
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    • 2005
  • Nuclides in radioactive wastes are assumed to be transported in the geosphere by groundwater and probably discharged into the biosphere. Quantitative evaluation of doses to human beings due to nuclide transport in the geosphere and through the various pathways in the biosphere is the final step of safety assessment of the radioactive waste repository. To calculate the flux to dose conversion factors (DCFs) for nuclides appearing at GBIs with their decay chains, a template ACBIO which is an AMBER case file based on mathematical model for the mass transfer coefficients between the compartments has been developed considering material balance among the compartments in biosphere and then implementing to AMBER, a general and flexible software tool that allows to build dynamic compartment models. An illustrative calculation with ACBIO is shown.

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HEALTH RISK ASSESSMENT OF HOUSEHOLD EXPOSURE TO INDOOR RADON IN ASSOCIATION WITH THE DWELLING'S AGE

  • Shahrokhi, Amin;Shokraee, Forough;Reza, Ali;Rahimi, Hasn
    • Journal of Radiation Protection and Research
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    • v.40 no.3
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    • pp.155-161
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    • 2015
  • Radon is a naturally occurring radioactive gas and a major indoor contribution of exposure to ionizing radiation in dwellings. $^{222}Rn$ is a health hazard gas what is responsible for thousand lung cancer deaths every year. In this study, indoor radon concentrations present in thirty representative houses in Mahallat city, Iran, were determined in order to estimate lung cancer risk associated with residential radon exposure. Long-term passive method, using CR-39, was used to measure the radon concentration. The results showed an association between the age of the dwellings and the indoor radon concentration that was found, in that the concentration of radon tended to increase as the age of the dwelling also increased. The indoor radon concentrations were calculated to be within the range of $23{\pm}2$ to $350{\pm}26Bq{\cdot}m^{-3}$, with an average of $158Bq{\cdot}m^{-3}$. The annual effective dose from inhaled radon and its decay products was calculated between $0.8{\pm}0.1$ and $12.3{\pm}0.9mSv{\cdot}y^{-1}$, with an average of $5.5mSv{\cdot}y^{-1}$. By taking into consideration the EPA recommendation and ICRP statement, the average annual risk of lung cancer from inhaled radon was calculated as 0.09%, 0.06%, 0.01%, and 0.03% for current smokers (CS), those who had ever smoked (ES), never smokers (NS) and the general population, respectively.

A Survey on Dietary Habit and Nutritional Knowledge for Elementary School Children's Nutritional Education (초등학생의 영양교육을 위한 식습관 및 영양지식 조사)

  • Ku, Pok-Ja;Lee, Kyoung-Ae
    • Journal of the Korean Society of Food Culture
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    • v.15 no.3
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    • pp.201-213
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    • 2000
  • The aim of this study is to survey the eating habits and nutritional knowledge of children in Pusan, with a view to uncovering problems and their underlying causes and cultivating desirable dietary habit and nutrition for children. Three hundred and fifty six elementary school students were asked questions about their eating habits and nutritional knowledge as well as general information about their personal characteristics. The results showed: 1. Only 53.5% of the subjects had breakfast every day. Seventy-six percent of the subjects had dinner every day. Only 40% of the children took meals and talked with family at both breakfast and dinner. Thus there was little opportunity for dietary guidance by parents. 2. About half of the subjects answered that their appetite decreased after eating snack foods between meals. A third of the subjects liked the baked goods as snacks. Because of their high sugar and fat content, they can damage children's health, resulting in child diabetes and tooth decay. For this reason, careful education is necessary to allow children to be able to select snack foods that are appropriate in kind and quantity. 3. About 85% of the subjects had an unbalanced diet. Therefore systematic nutrition education at school is necessary to instill in children the value of balanced diet. 4. Children preferred rice to other cereals as a staple food. They disliked kimchi, seasoned and blanched foods and salads as subsidiary foods. It is therefore necessary to teach children systematically the nutritional advantage of cereals and vegetables and to heighten their awareness of Korean food culture. 5. Children had a low level of nutritional knowledge. The knowledge of specific nutrients was lower than that of foods. In conclusion, systematical educational programs need to be developed at elementary school. These should include information about achieving a balanced diet, good eating habit, meal management and Korean dietary culture. Nutritional education at home must be emphasized.

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Free Volume in Polyers Note II。: Positron Annihilation lifetime Spectroscopy and Applications

  • G. Consolati;M. Pegoraro;L. Zanderighi
    • Korean Membrane Journal
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    • v.1 no.1
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    • pp.25-37
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    • 1999
  • positron annihilation Lifetime Spectroscopy has been extensively applied in recent years to investigate the free volume in polymers owing to the capability of the electron-positron bound system (positronium) to probe the typical size of sub-nanometric cavities among the macromolecular chains. In this paper we show recent results obtained through this technique in some amorphous polymeric mem-branes(olyurethanes. PUs and polytrimethilsylilpropine PTMSP) after a brief survey of the general features of the annihilation process as well as of the experimental apparatus. Lifetime of o-ps decay({{{{ tau _3}}}}) in PUs increases going from sub {{{{ TAU _g}}}} to over {{{{ TAU _g}}}} temperatures following a sigmoid curve. The coefficient of dilatation of the free volume fraction is shown to be the sum of two contributes due to the variation with T of the number of holes and of their mean volume. PAL spectrum of PTMSP freshly prepared shows four lifetime components: {{{{ tau _3}}}} and {{{{ tau _4}}}}: only are useful for free volume study. Two kinds of holes of different equivalent radius are reported ({{{{ gamma _s}}}} 4.60 nm and {{{{ gamma _1}}}} 0.754) The equivalent volume does not change in a range of 100 K. however the physical aging increases density and decreases oxygen permeability while {{{{ gamma _s}}}} goes down to 0.374 and r1 to 0.735 The number of holes obtained from the intensities{{{{ IOTA _3}}}} and {{{{ IOTA _4}}}} of PAL spectra decreases with aging 21.7% and 3.5% for large and small holes respectively.

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