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A Comparative Analysis on Elementary Students방 Scientific Attitudes by Questionnaire and Ethnographic Study (질문지법과 문화기술적 방법에 의한 초등학생의 과학적 태도에 대한 비교 분석)

  • 김운배;김효남
    • Journal of Korean Elementary Science Education
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    • v.19 no.1
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    • pp.1-13
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    • 2000
  • For a profound understanding about the elementary students' scientific attitude, I have performed this study based on the students' opinion by the ethnographic interview and participant observation of science classes. I have analyzed the data by qualitative data analyzing method, and compared the analyzed results with analyzed results by the Likert's scaled as il questionnaire method. To perform this study, I selected one elementary school located in an agricultural village in Choong-Buk Province in Korea and studied four 5th grade students. Here, I present results of this study as follows. First, in ethnographic interview, all informants represented positive reaction to scientific curiosity. But, It is appeared that there are external curiosity and internal curiosity. Internal curiosity is more closely and positively related to problem solving skills. Second, all informants represented positive open-mindness expressing their own opinions actively and accepting other students' opinions. Students who had positive critical-mindness and voluntariness recorded high scores in science achievement. Third, scientific attitude analyzed by ethnographic methods didn't correspond with scientific attitude measured by Likert's scale in all cases. I presumed this discrepant result could come from subjects' different tendency on replying to questionnaire and students' own criterion.

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A Comparative Study on Gender Differences in BMI, Body Weight Perception, Body Weight Satisfaction and Eating Behavior in Middle School Students (중학생의 체격지수, 체형인지, 체형만족 및 섭식행동에 관한 남ㆍ녀간의 비교연구)

  • 허혜경;박소미;김기연;송희영;전은표
    • Korean Journal of Health Education and Promotion
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    • v.21 no.3
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    • pp.53-66
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    • 2004
  • Purpose: To compare differences in BMI, body weight perception and satisfaction, and eating behavior by gender among middle school students. Methods: From 19 middle schools in W city four classes in two middle schools were selected by cluster sampling with multi-stage sampling. A structured questionnaire was answered by 143 adolescents. Results: Differences in BMI between boys and girls were significant (x$^2$=13.15, p=.00l). Boys reported higher ideal body weight than girls (t=6.33, p<.000l), and discrepancy between ideal body weight and body weight perception in girls was significantly greater than in boys(t=-5.0l, p<.0001). There was no significant gender difference in body weight perception but more boys were satisfied with their body weight(t=-4.48, p<.0001). Comparison of eating behavior showed that girls reported high scores in disinhibition (t=-2.29, p<.05) and hunger (t=-2.81, p<.01), while boys reported higher scores in cognitive restraints (t=3.22, p<.01). Conclusion: Interventions to help girls improve body image and satisfaction with body image are crucial. In order to establish proper diet habits and balanced nutritional status for adolescents, educational interventions should address characteristics of eating behaviors.

Critical Review on the Carcinogenic Potential of Pesticides Used in Korea

  • Choi, Sangjun
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.15
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    • pp.5999-6003
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    • 2014
  • Pesticides used in Korea are grouped by four classes of hazard (extremely, highly, moderately and slightly hazardous) based on acute oral and dermal toxicity in the rat. However, there is little information of carcinogenic effects. The aim of this study was to evaluate potential carcinogenicity for active ingredients of pesticides used in Korea. A total of 1,283 pesticide items were registered under the Pesticide Control Act of which 987 were commercially available. Of these 987 items, 360 active ingredients not duplicated were evaluated for carcinogenicity using the carcinogen list established by the US Environmental Protection Agency (EPA). Some 25 out of 360 ingredients were classified as likely to be carcinogenic (probable) to humans and 52 had suggestive evidence of carcinogenic potential (suspected) based on the US EPA classification. Some 31% of 987 items contained probable or suspected human carcinogenic ingredients. Carcinogenic pesticides accounted for 24% (5,856/24,795 tons) of the total volume of consumption in Korea. Interestingly, pesticides with lower acute toxicity were found to have higher carcinogenic potential. Based on these findings, the study suggests that it is important to provide information on long-term toxicity to farmers, in addition to acute toxicity data.

Knowledge Towards HPV infection and HPV Vaccines among Syrian Mothers

  • Alsaad, Mohammed A.;Shamsuddin, Khadijah;Fadzil, Fariza
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.3
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    • pp.879-883
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    • 2012
  • Cervical cancer is caused by HPV infection and can be prevented by early vaccination. Objective: To assess Syrian women's level of knowledge and determinants of good knowledge of cervical cancer, HPV infection and its vaccines. Methods: A cross sectional survey was undertaken among mothers with daughters in sixth grade classes enrolled in primary schools in Aleppo city, Syria. Samples were selected through cluster sampling and data collected using a self-administered questionnaire. Results: Less than a third of the mothers had heard of HPV infection and vaccines against cervical cancer and levels of knowledge were generally low. Good knowledge was associated with high education level, higher family monthly income, having few - less than four children, positive history of cervical cancer screening, and working or having relatives working in the medical field. The main source of information was television and few reported health care providers as a source of knowledge on HPV infection and vaccine. Conclusion: Since knowledge of HPV infection and its connection with cervical cancer and its vaccine are low, more efforts must be made to educate Syrians prior to introduction of any HPV vaccination programme. Public health efforts must focus on educating mothers, the public as well as health care providers.

A Study on the Evaluation of Material Degradation using Ball Indentation Method (압입법을 이용한 재료 열화의 평가에 관한 연구)

  • Kim, Jeong-Pyo;Seok, Chang-Sung;Ahn, Ha-Neul
    • Proceedings of the KSME Conference
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    • 2000.11a
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    • pp.171-176
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    • 2000
  • As huge energy transfer systems like a nuclear power plant, steam power plant and petrochemical plant are operated for a long time, mechanical properties are changed by degradation. The life time of the systems can be affected by the mechanical properties. BI(Ball Indentation) test has a potential to replace conventional fracture tests like a uniaxial tensile test, fracture toughness test, hardness test and so on. In this paper, we would like to present the aging evaluation technique by the BI method. The four classes of the thermally aged 1Cr-1Mo-0.25V specimens were prepared using an artificially accelerated aging method. Tensile tests, fracture toughness tests, hardness tests and BI tests were performed. The results of the BI tests were in good agreement with fracture characteristics by a standard fracture test method. The IDE(Indentation Deformation Energy) of a BI technique as a new parameter for evaluating a degradation was suggested and the new IDE parameter clearly depicts the degradation degree.

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A Study on Human Training System for Prosthetic Arm Control (의수제어를 위한 인체학습시스템에 관한 연구)

  • 장영건;홍승홍
    • Journal of Biomedical Engineering Research
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    • v.15 no.4
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    • pp.465-474
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    • 1994
  • This study is concerned with a method which helps human to generate EMG signals accurately and consistently to make reliable design samples of function discriminator for prosthetic arm control. We intend to ensure a signal accuracy and consistency by training human as a signal generation source. For the purposes, we construct a human training system using a digital computer, which generates visual graphes to compare real target motion trajectory with the desired one, to observe EMG signals and their features. To evaluate the effect which affects a feature variance and a feature separability between motion classes by the human training system, we select 4 features such as integral absolute value, zero crossing counts, AR coefficients and LPC cepstrum coefficients. We perform a experiment four times during 2 months. The experimental results show that the hu- man training system is effective for accurate and consistent EMG signal generation and reduction of a feature variance, but is not correlated for a feature separability, The cepstrum coefficient is the most preferable among the used features for reduction of variance, class separability and robustness to a time varing property of EMG signals.

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Measurements of Impervious Surfaces - per-pixel, sub-pixel, and object-oriented classification -

  • Kang, Min Jo;Mesev, Victor;Kim, Won Kyung
    • Korean Journal of Remote Sensing
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    • v.31 no.4
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    • pp.303-319
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    • 2015
  • The objectives of this paper are to measure surface imperviousness using three different classification methods: per-pixel, sub-pixel, and object-oriented classification. They are tested on high-spatial resolution QuickBird data at 2.4 meters (four spectral bands and three principal component bands) as well as a medium-spatial resolution Landsat TM image at 30 meters. To measure impervious surfaces, we selected 30 sample sites with different land uses and residential densities across image representing the city of Phoenix, Arizona, USA. For per-pixel an unsupervised classification is first conducted to provide prior knowledge on the possible candidate spectral classes, and then a supervised classification is performed using the maximum-likelihood rule. For sub-pixel classification, a Linear Spectral Mixture Analysis (LSMA) is used to disentangle land cover information from mixed pixels. For object-oriented classification several different sets of scale parameters and expert decision rules are implemented, including a nearest neighbor classifier. The results from these three methods show that the object-oriented approach (accuracy of 91%) provides more accurate results than those achieved by per-pixel algorithm (accuracy of 67% and 83% using Landsat TM and QuickBird, respectively). It is also clear that sub-pixel algorithm gives more accurate results (accuracy of 87%) in case of intensive and dense urban areas using medium-resolution imagery.

Interlaboratory Comparison of Critical Current Measurements on Ag-sheathed Bi-2223 tapes (Bi-2223선재의 임계전류 측정기술 비교)

  • Lee, Kyu-Won;Han, Gi-Youl
    • Progress in Superconductivity
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    • v.3 no.1
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    • pp.99-103
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    • 2001
  • We have conducted two runs of interlaboratory comparison on Ag-sheathed Bi-2223 tapes to evaluate the level of measurement techniques for the critical current measurement. Two classes of specimens were prepared for parallel and serial routings and sent to four participating laboratories. The critical currents of specimens were measured at 77 K in zero magnetic field. In the first comparison, we used twenty different Bi-2223 tapes as specimens for comparison and participating laboratories measured the specimens using their own instruments and procedures. As a result, the scattering of data on the first comparison showed -3.0% to +l2.2% for the parallel routing and -0.7% to +l5.1% for the serial routing. Major sources of these variations were attributed to different measurement techniques. Thus, the second comparison of measurement was done on the same specimens under specified measurement conditions, particularly in terms of cooling procedure and sweep rate of the test current. The variations for the second comparison were decreased -3.1% to +3.2% far the parallel routing and -1.8% to +7.7% fur the serial routing.

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A survey on the prevalence of internal parasites in the Korean indigenous goats of Kyungbuk area (경북지역의 흑염소 내부기생충 감염률 조사)

  • 박노찬;도재철;김수웅;송해범
    • Korean Journal of Veterinary Service
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    • v.20 no.4
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    • pp.349-358
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    • 1997
  • From December 1995 to July 1997, a total of 546 Korean indigenous goats were examined for the presence of internal parasites by parenchymal organs and fecal examinations. Four hundreds seventy eight(87.5%) of the goats were infected with 4 classes and 12 parasitic species. The nematodes were Haemonchus contortus(57.5%), Oesophagostomun venulosum (52.6%), Strongyloides papillosus(48.4%), Ostertagia sp(28.4%), Trichostrongylus colubriformis(17.0%), and Trichuris ovis(13.2%). The trematodes were Paramphistomum sp(17.6%), Fasciola hepatica(15.4%), and Eurytrema Pancreaticum (8.8%). The cestode was Moniezia expansa(16.7%), and the protozoa were Eimeria sp(74.9%) and Toxoplasma gondii(8.6%). The incidence of single or mixed infections among 12 parasitic species were one species infection (6.2%), 2 species(11.5%), 3 species(19.6%), 4 species(24.9%), 5 species(17.8%), 6 species(5.9 %), and 7 species(1.6), respectively. The level of infection according to the age was considerably higher under one year(97.2%) than between one and two years(89.7%), and over two years(69.3%) Among 12 parasites, seasonal pattern was remarkably observed. Most paracites were detected at the highest level in the Winter, whereas Strongyloides papillosus and Paramphistomum sp were in the Spring, and Ostertagia sp and Fasciola hepatica were in the Autumn. Infection rates of Anaplasma sp were 8.6% of 210 goats by blood smear method, and 51.0% by complement fixation test.

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Description of ten unrecorded bacterial species isolated from Ostrea denselamellosa and Eriocheir japonica from the Seomjin River

  • Choi, Ahyoung;Han, Ji-Hey;Kim, Eui-Jin;Cho, Ja Young;Hwang, Sun-I
    • Korean Journal of Environmental Biology
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    • v.37 no.4
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    • pp.592-599
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    • 2019
  • Ostrea denselamellosa and Eriocheir japonica samples were collected from the Seomjin River in 2019 as part of the "Research of Host-Associated Bacteria" research program. Almost 200 bacterial strains were isolated from the O. denselamellosa and E. japonica samples and subsequently identified by 16S rRNA gene sequencing. Among the bacterial isolates, ten strains possessed greater than 98.7% sequence similarity with published bacterial species that had not previously been recorded in Korea. These species were phylogenetically diverse, belonging to three phyla, four classes, seven orders, and eight genera. At the genus and class level, the previously unrecorded species belonged to Pseudoalteromonas, Aliivibrio, Rheinheimera, Leucothrix, and Shewanella of the class Gamma-proteobacteria, Olleya of the class Flavobacteriia, Algoriphagus of the class Cytophagia, and Lactococcus of the class Bacilli. The previously unrecorded species were further characterized by examining their Gram staining, colony and cell morphology, biochemical properties, and phylogenetic positions.