• 제목/요약/키워드: variable selections

검색결과 19건 처리시간 0.024초

중학생의 소집단 자유탐구활동 중 물리 영역 탐구문제의 구성과 변인 추출 및 명료화 과정 (Middle School Students' Construction of Physics Inquiry Problems and Variables Isolation and Clarification during Small Group Open-inquiry Activities)

  • 유준희;김종숙
    • 한국과학교육학회지
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    • 제32권5호
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    • pp.903-927
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    • 2012
  • 본 연구는 2007년 개정 교육과정에서 도입된 자유탐구활동의 지도방안에 대한 시사점을 얻기 위하여 중학생의 소집단 자유탐구 활동 중 물리 영역 탐구문제 구성과정을 변인의 추출 및 명료화의 관점에서 분석하였으며, 변인의 명료화가 진행되는 단계에서 학생의 어려움을 조사하였다. 본 연구의 참여 학생은 서울 소재 대학 영재원 과학반 소속 중학생 4명이며 '계란낙하'라는 하나의 주제를 가지고 13차시, 30시간동안 자유탐구활동을 진행하였다. 학생들의 탐구문제 구성에서 나타난 변인의 추출 및 명료화 과정을 분석하기 위하여 선행연구를 토대로 변인 추출의 수준 및 변인의 명료화 수준에 대한 분석틀을 제안하였다. 학생들은 과학적 탐구의 과정을 반복적이고 점진적으로 수행하면서 탐구문제를 5차례 변경하였다. 종속변인이 독립변인보다 먼전 추출되었으며 변인 추출의 수준 및 명료화의 수준도 높게 나타났다. 학생들은 여러 종류의 독립변인들을 외연적 수준에서 추출하는 것으로 나타났는데, 이는 학생들은 이론적 설명 모형의 부재로 중요한 독립변인을 추출하는 것을 어려워하며 그 때문에 독립변인과 통제변인을 구분하지 못하는 현상도 함께 나타나는 것으로 해석할 수 있다. 학생들은 탐구주제의 선택 뿐 만 아니라 종속변인과 독립변인의 추출 및 정의하는데 현실적 여건에 의해 제약을 받는 것으로 나타났다. 또한 학생들은 종속변인이나 독립변인을 추출하는데 있어서 모두 감각적인 현상이나 외연적 특성인 깨지는 것, 높이 등이 부각되는 것으로 판단되었다. 종속변인의 이론적 정의나 조작적 정의를 하는데 있어서 해당 지식이 부족하여 어려움을 겪었으며, 그 결과 해당하는 변인의 과학 사전적 정의를 이해해도 해당 탐구상황에 적용하여 설명모형을 만들어내지는 못하였는데, 이는 이후 독립변인 및 통제 변인을 추출하는데 영향을 준 것으로 판단된다. 이론적 설명모형의 부재는 학생들의 이론적 배경에 대한 이해의 부족에서도 비롯되지만, 과학적 탐구가 시행착오적인 해보기나 무작정적인 변인사이의 관계 설정하기가 아닌 이론에 근거한 실증적 활동이라는 인식이 부족한 것에 기인한다고 판단할 수 있다.

와인 소비자의 선택 속성의 만족도에 관한 연구 (The Relationship between Wine-Selection Attributes and Consumer Satisfaction)

  • 방진식;최태호;전진화
    • 한국조리학회지
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    • 제12권2호
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    • pp.88-105
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    • 2006
  • Entering into the new millennium, the Korean wine market has recorded the highest growth rate among the domestic alcoholic beverage market and been recognized as a rapidly emerging market with further escalation potential. Responding to the current drastic escalation of Korean wine market in terms of its volume, the present study scrutinizes the considerable wine-selection attributes that are related to individual wine consumer‘s characteristics including demographic variables. These attributes are also expected to be precursors of wine consumers‘ satisfaction. ANOVA results suggest that each demographical variable-gender, age, income level, and the frequency of wine consumption-pertains to specific wine-selection attribute(s). Likewise, wine consumers‘ characteristics are also associated with those attributes. As wine consumers are experienced, they rely less on information; rather, their selections tend to be dependent upon quality, value, contexts, and preferences. The subsequent multiple-regression investigating the relationship between wine-selection attributes and satisfaction signifies that quality, contexts, and preference attributes are the substantial antecedents of wine consumers‘ satisfaction. When consumers purchase a wine, "information on purchase" was the most important criterion for the Newcomers and the Outsiders, while the Connoisseurs mainly depended on "marketability", "wine values" and "viticulture environment". "Preference" attributes influenced the Aspirants the most in buying decision. The Newcomers and the Outsiders need more information before deciding to purchase as their wine knowledge was very limited. The Connoisseurs were likely to consider the quality as a more important factor than the price and it is necessary to develop high quality wine at a reasonable price in order to attract this group.

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Molecular Characterization of Chicken Toll-like Receptor 7

  • Chai, Han-Ha;Suk, Jae Eun;Lim, Dajeong;Lee, Kyung-Tai;Choe, Changyong;Cho, Yong-Min
    • Reproductive and Developmental Biology
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    • 제39권4호
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    • pp.105-115
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    • 2015
  • Toll-like receptor 7 (TLR7) is critical for the triggering of innate immune response by recognizing the conserved molecular patterns of single-stranded RNA (ssRNA) viruses and mediated antigenic adaptive immunity. To understand how TLR7 distinguish pathogen-derived molecular patterns from the host self, it is essential to be able to identify TLR7 receptor interaction interfaces, such as active sites or R848-agonist binding sites. The functional interfaces of TLR7 can serve as targets for structure-based drug design in studying the TLR7 receptor's structure-function relationship. In contrast to mammalian TLR7, chicken TLR7 (chTLR7) is unknown for its important biological function. Therefore, it has been targeted to mediate contrasting evolutionary patterns of positive selection into non-synonymous SNPs across eleven species using TLR7 conservation patterns (evolutionary conserved and class-specific trace residues), where protein sequence differences to the TLR7 receptors of interest record mutation that have passed positive section across the species. In this study, we characterized the Lys609 residue on chTLR7-ECD homodimer interfaces to reflect the current tendency of evolving positive selection to be transfer into a stabilization direction of the R848-agonist/chTLR7-ECDs complex under the phylogenetically variable position across species and we suggest a potential indicator for contrasting evolutionary patterns of both the species TLR-ECDs.

고점도 펄프를 위한 새로운 한지 펄프화법의 개발(제1보) - 닥나무 백피의 상압 펄프화 특성 - (Development of High Viscosity Pulping Method for Korean Paper (I) - Atmospheric Pressure Pulping Characteristics of Paper Mulberry White Bast -)

  • 이상현;최태호
    • 펄프종이기술
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    • 제43권2호
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    • pp.57-65
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    • 2011
  • Pulping of paper mulberry (Broussonetia kazinoki) white bast has been examined by novel atmospheric pressure pulping methods. The viscosity of pulp has been found to be highly sensitive and variable with pulping methods. Therefore, selections of pulping chemicals and conditions are very important. Two kinds of pulping procedures were employed for the high viscosity pulp manufacturing. The one is ammonium oxalate treatment and the other is sodium chlorite and acetic acid treatment. Not only chemical components and pulp yields which of paper mulberry white bast but also water retention value (WRV), whiteness index, yellowness index, and colors of every pulp were examined. The hot water, 1% NaOH, and ethanol-benzene extractives which of paper mulberry white bast were 4.48%, 28.45%, and 2.84%, respectively. The contents of holocellulose, lignin, and ash were 90.66%, 1.05%, and 2.18%, respectively. In the pulp yields, group 1 which treated with only ammonium oxalate were 77.04-81.71%, group 2 which treated with ammonium oxalate and acidified sodium chlorite separately and washed between first and second stages were 64.15-83.90%, group 3 which treated with ammonium oxalate and acidified sodium chlorite separately and not washed between first and second stages were 57.35-73.17%, and group 4 which treated with mixed ammonium oxalate and acidified sodium chlorite were 66.58-68.43%. The pulps treated with acidified sodium chlorite showed high whiteness index, but the pulps treated with only ammonium oxalate showed high yellowness index. Variations in the combinations of treatments resulted in different pulp characteristics.

분위회귀분석을 이용한 개업 치과의사의 의료수익과 소득에 미치는 요인 (Factors Associated with Dental Revenue and Income of Self-Employed Dentist by Using a Quantile Regression Method)

  • 최형길;김명기
    • 보건행정학회지
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    • 제25권3호
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    • pp.240-251
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    • 2015
  • Background: Dentist's income is quite variable. We investigate the factors underlying the distribution of dental revenue and dentist income. Methods: Financial and structural variables of private dental practices(N=13,967) were examined with 2010 Economic Census microdata which include non-insurance revenue. We conducted quantile regression method(QRM) and ordinary least square(OLS) in treating skewness and heteroskedasticity of distributions. The effective estimation for the upper and lower range of distribution becomes possible by QRM. Results: Mid-career dentists are shown to have higher revenue and income. Male dentists achieve the higher revenue and income than female dentists in all quantiles. Group practices show lower income per owner than solo practices significantly. The revenue and income are increased with increasing size of clinics. The high cost in renting the clinic office is found to have a big positive effect on the revenue but a little positive effect on the income. Interestingly the density of dentists shows negative effect on the lowest quantile of the revenue but positive effect on the highest quantile. The lowest quantile of the revenue in the capital areas have the relatively high revenue. The lowest quantile of the income in metropolitan city show higher income than those in other areas significantly. Conclusion: The suggested QRM is shown to have more effective and efficient tool in finding out determinants of dentists' revenue and income of our concern. The results of this study are expected to be employed for dentists preparing for the opening practices in their organizational settings and locational selections. The distributional efficiency of dental human resources could be accomplished if policy makers guide dentists with this knowledge.

교육서비스 품질과 교육성과의 기대일치여부가 행동의도에 미치는 영향: 글로벌기업의 TOEIC사업을 중심으로 (Influence of the Education Service Quality and Result Expectations on Behavioral Intention: Focus on the TOEIC Business of a Global Company)

  • 강호계;송인암;황희중
    • 유통과학연구
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    • 제11권2호
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    • pp.71-81
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    • 2013
  • Purpose - The TOEIC test has been leading the change in the quality and the globalization of companies for about last 30 years. The TOEIC test is taken by about two million people each year and is used as a criterion to select new employees in companies or government offices, for performance ratings, and for overseas posting selections. Universities also use TOEIC test in various ways. Since the TOEIC test is used for the selection of new students for admission, transferring extra credits, scholarships, graduation certification, and admission of international students studying abroad, many universities all over the country provide students with TOEIC study lectures through their own language institutes. Despite the fact, there has been no research on the service quality or even the current situation of these institutes. Thus, this study aims to evaluate the factors that impact TOEIC lecture service quality and analyzes the effect of the expectation related to the education service quality and the result of education on intentional behavior. Research design, data, methodology - Data was collected by administering a survey to current TOEIC students from different university language institutes. The survey questionnaire comprised of a five-point Likert scale. The demographic analysis was conducted using the frequency analysis method and the factor analysis was conducted to verify the validity of questionnaire over any variable. The reliability analysis was conducted to verify the reliability of the results. Besides, multiple regression analysis, regression analysis, and mediated effect verification were also conducted. For education service quality, four different independent variables such as reliability, response, conviction, and sympathy were considered using the SERVQUAL survey model. Based on the research models, the study hypotheses below were formulated in order to recognize an effect relationship between the variables. The four hypotheses are, "the hypothesis on education service quality and TOEIC study result expectation," "the hypothesis on education service quality and behavioral intention," "the hypothesis on study result expectation and behavioral intention," and "the hypothesis on study result expectation and mediated effect." Results - The results are as follows. First, the factors like response, conviction, and sympathy have a positive influence on TOEIC study result expectations. Second, the TOEIC study result expectation has a positive influence on the factors of behavioral intention such as re-sign up, positive word-of-mouth, "loyalty towards school." Third, it was verified that the mediated effect on behavioral intention was influenced by education service quality at university foreign language institute, while the study result expectation has only a partial mediated effect. Conclusions - The implications of this study are summarized as follows: First, it suggests a new research model for the effect of the expectation related to the education service quality and the result of education in the university language institutes on the behavioral intention. Second, it has established a relationship between the education service quality and study result expectation by verifying the mediated effect on them.

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발명의 특허성 및 특허의 유효성 분쟁결과에 영향을 미치는 요인분석 (Determinants of Success in Ex-parte and Inter-parte Patent Litigation)

  • 추기능;오준병
    • 기술혁신연구
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    • 제20권3호
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    • pp.57-91
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    • 2012
  • 본 연구는 우리나라에서 하나의 발명이 유효한 특허권으로 확정되는 과정에서 나타나는 두 가지 분쟁 형태, 즉 결정계(ex parte)와 당사자계(inter parte)를 대상으로 하여 분쟁에서의 승리에 영향을 미치는 요인에 대한 분석을 한 최초의 논문이며 기업, 소송, 대리인, 특허차원에서의 특성들을 설명변수로 구성하여 2단계 프로빗 회귀분석을 하였다. 분석모형에 따르면, 상대적 심판제기율, 심판제기까지 걸린 시간, 대리인 교체, 복수(複數) 대리인 등에서 결정계와 당사자계간에 평균 한계효과(average marginal effect)의 차이가 나타났다. 결정계의 경우 이들 변수가 승소확률을 낮추는 요인이 되지만, 당사자계의 경우 반대로 승소 확률을 높이는 요인으로 작용하였다. 그런데, 결정계와 당사자계 모두에서 특허를 출원한 대리인의 경험이 많을수록 승소확률을 낮추는 역설적인 결과가 나타났다. 그러나, 이는 대리인의 경험이 많을수록 심판제기 확률이 높아지는 표본선택(sample selection)의 효과가 이미 반영되어 있기 때문이며, 대리인 경험의 전 범위에 적용할 수는 없을 것이다. 특허의 가치를 나타내는 청구항수는 승소확률을 높이는 것으로 나타났다. 본 연구에서는 자연인인 특허대리인에 한정하였고, 특허대리인의 경험을 출원대리에 한정하였으나, 앞으로 소송대리의 경험, 특허법인 차원에서의 특성자료, 더 나아가 특허인용 자료와 연결이 된다면 많은 추가적인 연구주제들이 파생될 수 있을 것이다.

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Perspective of breaking stagnation of soybean yield under monsoon climate

  • Shiraiwa, Tatsuhiko
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.8-9
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    • 2017
  • Soybean yield has been low and unstable in Japan and other areas in East Asia, despite long history of cultivation. This is contrasting with consistent increase of yield in North and South America. This presentation tries to describe perspective of breaking stagnation of soybean yield in East Asia, considering the factors of the different yields between regions. Large amount of rainfall with occasional dry-spell in the summer is a nature of monsoon climate and as frequently stated excess water is the factor of low and unstable soybean yield. For example, there exists a great deal of field-to-field variation in yield of 'Tanbaguro' soybean, which is reputed for high market value and thus cultivated intensively and this results in low average yield. According to our field survey, a major portion of yield variation occurs in early growth period. Soybean production on drained paddy fields is also vulnerable to drought stress after flowering. An analysis at the above study site demonstrated a substantial field-to-field variation of canopy transpiration activity in the mid-summer, but the variation of pod-set was not as large as that of early growth. As frequently mentioned by the contest winners of good practice farming, avoidance of excess water problem in the early growth period is of greatest importance. A series of technological development took place in Japan in crop management for stable crop establishment and growth, that includes seed-bed preparation with ridge and/or chisel ploughing, adjustment of seed moisture content, seed treatment with mancozeb+metalaxyl and the water table control system, FOEAS. A unique success is seen in the tidal swamp area in South Sumatra with the Saturated Soil Culture (SSC), which is for managing acidity problem of pyrite soils. In 2016, an average yield of $2.4tha^{-1}$ was recorded for a 450 ha area with SSC (Ghulamahdi 2017, personal communication). This is a sort of raised bed culture and thus the moisture condition is kept markedly stable during growth period. For genetic control, too, many attempts are on-going for better emergence and plant growth after emergence under excess water. There seems to exist two aspects of excess water resistance, one related to phytophthora resistance and the other with better growth under excess water. The improvement for the latter is particularly challenging and genomic approach is expected to be effectively utilized. The crop model simulation would estimate/evaluate the impact of environmental and genetic factors. But comprehensive crop models for soybean are mainly for cultivations on upland fields and crop response to excess water is not fully accounted for. A soybean model for production on drained paddy fields under monsoon climate is demanded to coordinate technological development under changing climate. We recently recognized that the yield potential of recent US cultivars is greater than that of Japanese cultivars and this also may be responsible for different yield trends. Cultivar comparisons proved that higher yields are associated with greater biomass production specifically during early seed filling, in which high and well sustained activity of leaf gas exchange is related. In fact, the leaf stomatal conductance is considered to have been improved during last a couple of decades in the USA through selections for high yield in several crop species. It is suspected that priority to product quality of soybean as food crop, especially large seed size in Japan, did not allow efficient improvement of productivity. We also recently found a substantial variation of yielding performance under an environment of Indonesia among divergent cultivars from tropical and temperate regions through in a part biomass productivity. Gas exchange activity again seems to be involved. Unlike in North America where transpiration adjustment is considered necessary to avoid terminal drought, under the monsoon climate with wet summer plants with higher activity of gas exchange than current level might be advantageous. In order to explore higher or better-adjusted canopy function, the methodological development is demanded for canopy-level evaluation of transpiration activity. The stagnation of soybean yield would be broken through controlling variable water environment and breeding efforts to improve the quality-oriented cultivars for stable and high yield.

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유전자 알고리즘을 이용한 다분류 SVM의 최적화: 기업신용등급 예측에의 응용 (Optimization of Multiclass Support Vector Machine using Genetic Algorithm: Application to the Prediction of Corporate Credit Rating)

  • 안현철
    • 경영정보학연구
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    • 제16권3호
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    • pp.161-177
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    • 2014
  • 기업신용등급은 금융시장의 신뢰를 구축하고 거래를 활성화하는데 있어 매우 중요한 요소로서, 오래 전부터 학계에서는 보다 정확한 기업신용등급 예측을 가능케 하는 다양한 모형들을 연구해 왔다. 구체적으로 다중판별분석(Multiple Discriminant Analysis, MDA)이나 다항 로지스틱 회귀분석(multinomial logistic regression analysis, MLOGIT)과 같은 통계기법을 비롯해, 인공신경망(Artificial Neural Networks, ANN), 사례기반추론(Case-based Reasoning, CBR), 그리고 다분류 문제해결을 위해 확장된 다분류 Support Vector Machines(Multiclass SVM)에 이르기까지 다양한 기법들이 학자들에 의해 적용되었는데, 최근의 연구결과들에 따르면 이 중에서도 다분류 SVM이 가장 우수한 예측성과를 보이고 있는 것으로 보고되고 있다. 본 연구에서는 이러한 다분류 SVM의 성능을 한 단계 더 개선하기 위한 대안으로 유전자 알고리즘(GA, Genetic Algorithm)을 활용한 최적화 모형을 제안한다. 구체적으로 본 연구의 제안모형은 유전자 알고리즘을 활용해 다분류 SVM에 적용되어야 할 최적의 커널 함수 파라미터값들과 최적의 입력변수 집합(feature subset)을 탐색하도록 설계되었다. 실제 데이터셋을 활용해 제안모형을 적용해 본 결과, MDA나 MLOGIT, CBR, ANN과 같은 기존 인공지능/데이터마이닝 기법들은 물론 지금까지 가장 우수한 예측성과를 보이는 것으로 알려져 있던 전통적인 다분류 SVM 보다도 제안모형이 더 우수한 예측성과를 보임을 확인할 수 있었다.