• Title/Summary/Keyword: understanding of hypothesis

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Numerical Simulation of NIL Process Based on Continuum Hypothesis (연속체 가정을 통한 NIL 공정의 전산모사)

  • Kim, Seung-Mo;Lee, Woo-Il
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.532-537
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    • 2007
  • Nano imprint lithography(NIL) is a cost-efficient, high-throughput processing technique to transfer nano-scale patterns onto thin polymer films. Polymers used as the resist include UV cured resins as well as thermoplastics such as polymethyl-methacrylate(PMMA). In this study, an analytic investigation was performed for the NIL process of transferring nano scale patterns onto polymeric films. Process optimization calls for a thorough understanding of resist flow during the process. We carried out 2D and 3D numerical analyses of resist flow during NIL process. The simulation incorporated continuum-hypothesis and the effects of surface tension were taken into account. For a more effective prediction of free surface, fixed grid scheme with the volume of fluid (VOF) method were used. The simulation results were verified with experimental results qualitatively. And the parametric study was performed for various process conditions.

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Investment Strategies for KOSPI Index Using Big Data Trends of Financial Market (금융시장의 빅데이터 트렌드를 이용한 주가지수 투자 전략)

  • Shin, Hyun Joon;Ra, Hyunwoo
    • Korean Management Science Review
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    • v.32 no.3
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    • pp.91-103
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    • 2015
  • This study recognizes that there is a correlation between the movement of the financial market and the sentimental changes of the public participating directly or indirectly in the market, and applies the relationship to investment strategies for stock market. The concerns that market participants have about the economy can be transformed to the search terms that internet users query on search engines, and search volume of a specific term over time can be understood as the economic trend of big data. Under the hypothesis that the time when the economic concerns start increasing precedes the decline in the stock market price and vice versa, this study proposes three investment strategies using casuality between price of domestic stock market and search volume from Naver trends, and verifies the hypothesis. The computational results illustrate the potential that combining extensive behavioral data sets offers for a better understanding of collective human behavior in domestic stock market.

Hypothesis Testing: Means and Proportions (평균과 비율 비교)

  • Pak, Son-Il;Lee, Young-Won
    • Journal of Veterinary Clinics
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    • v.26 no.5
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    • pp.401-407
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    • 2009
  • In the previous article in this series we introduced the basic concepts for statistical analysis. The present review introduces hypothesis testing for continuous and categorical data for readers of the veterinary science literature. For the analysis of continuous data, we explained t-test to compare a single mean with a hypothesized value and the difference between two means from two independent samples or between two means arising from paired samples. When the data are categorical variables, the $x^2$ test for association and homogeneity, Fisher's exact test and Yates' continuity correction for small samples, and test for trend, in which at least one of the variables is ordinal is described, together with the worked examples. McNemar test for correlated proportions is also discussed. The topics covered may provide a basic understanding of different approaches for analyzing clinical data.

Perspectives on a Critical Period for Language Acquisition: Implications for language research and practice

  • Lim, Ja-Yeon
    • Lingua Humanitatis
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    • v.7
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    • pp.335-353
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    • 2005
  • In recent years there has been much discussion about whether there is a critical, or sensitive period for language acquisition. Research on a critical period provides an excellent example around which we can organize a discussion of the behavioral and neural evidence. In this paper, the early history of critical periods and evidence for the existence of critical periods in various domains of human cognition and learning are reviewed. Followed by this overview, evidence for a critical period in both linguistic and non linguistic area are presented. The paper then provides some unresolved questions regarding a critical period in language acquisition and states what the outcome of this issues mean for an understanding of language acquisition. Finally the paper concludes with some educational implications of a critical period for practice.

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Ionic Polymer Transducers in sensing: the streaming potential hypothesis

  • Weiland, Lisa Mauck;Akle, Barbar
    • Smart Structures and Systems
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    • v.6 no.3
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    • pp.211-223
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    • 2010
  • Accurate sensing of mechanical strains in civil structures is critical for optimizing structure reliability and lifetime. For instance, combined with intelligent control systems, electromechanical sensor output feedback has the potential to be employed for nondestructive damage evaluation. Application of Ionic Polymer Transducers (IPTs) represents a relatively new sensing approach with more than an order of magnitude higher sensitivity than traditional piezoelectric sensors. The primary reason this sensor has not been widely used to date is an inadequate understanding of the physics responsible for IPT sensing. This paper presents models and experiments defending the hypothesis of a streaming potential sensing mechanism.

A STUDY IF PERSONALITY STRUCTURE AND HIERARCHY OF NEEDS IN COLLEGIATE NURSING STUDENTS (간호대학생의 욕구구조에 관한 일 연구)

  • 최계영
    • Journal of Korean Academy of Nursing
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    • v.4 no.1
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    • pp.38-49
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    • 1974
  • Presently, the performance level of the college student has received a great deal of attention, particularly in the area of professional education. The problem of under achievement, especially in areas dealing with science and technology, has gone through considerable investigation by numerous Psychologists and Educators. Thus for, however, they have not been successful in determining conclusively the non-intellectual factors involved. The maladjustment problem of these students has been a thorn in the side of nursing education for some time. This topic has been discussed among nursing educators without any tangible results. Furthermore, the fact that the number of students who withdraw from nursing education programs before graduation has increased. This represents a major problem for nursing education. This problem area had increased attention drawn to it on October 1957, when Russia successfully launched to first satellite "Sputnik" into space. Various studies seem to indicate that factors related to over achievement and under.achievement can be found in the motivation of the students. This study is aimed at testing 3 hypotheses which hopefully will lead to a better understanding of the learning activities of nursing students and to determine some of their nonintellectually personality traits. Hypothesis I: learning activities in nursing students and persona1ity are correlated, there will be significant differences in personality need structures between 4 classes of nursing collegiate students. Sub-hypothesis: There will also be significant differences in the degree of student satisfaction in her major subject. Hypothesis I: If there is a special personality need structure which is required for the clinical learning activity in general, then there will be significant differences between the personality need structures of under-achievers and overachiever. Hypothesis II : If each clinical nursing subject requires different personality need structures, then there will be differences in personality need structure between the different clinical groups Methodology: 1. Tool: A Korean translation and correction of the Edwards Personal Preference Schedule of U.S.A. was used. 2. Subject and Test Method: Subjects were nursing students at Yonsei University, who enrolled for Fall semester of 1971. The Researcher herself executed the test for the test for the class as a group, and the absent students were tested indidually. Out of 307 students, 293 students (95.4%) were reported. 3. Statistical treatment: The mean and standard deviation for each of the 15 personality need variables were computed and the value of T-test was obtained to determine the differences in the personality need structures between each group. Results: 1, For the first hypothesis, the personality need structures between each of the 4 classes and the reported degree of satisfaction in major subject showed significant differences. Therefore the hypothesis I was accepted. 2. The comparison of personality need structure of under-achievers and over-achievers in clinical fields showed significant differences. Thus hypothesis II was accepted. 3. Personality need structure between clinical subject groups showed significant differences therefore the 3rd hypothesis was accepted.

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Influences of Cognitive Conflict and Non-cognitive Variables Induced by Discrepant Event and Alternative Hypothesis on Conceptual Change (변칙사례 및 대안가설에 의해 유발된 인지갈등과 비인지적 변인이 개념변화에 미치는 영향)

  • Kang, Hun-Sik;Kwack, Jin-Ha;Kim, You-Jung;Noh, Tae-Hee
    • Journal of the Korean Chemical Society
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    • v.51 no.1
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    • pp.56-64
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    • 2007
  • This study examined the influences of cognitive conflict and anxiety induced by a discrepant event and an alternative hypothesis, attention, and effort on conceptual change. Two hundred three students having misconceptions about density were selected from 462 seventh graders based on the results of a preconception test. Tests of cognitive responses and anxiety to a discrepant event were administered before and after presenting an alternative hypothesis. Computer-assisted instruction (CAI) was then provided to students as a conceptual change intervention. Tests assessing attention and effort allocated to the CAI, and conceptual understanding were administered as posttests. Cognitive conflict induced by a discrepant event was found to increase after presenting an alternative hypothesis. Pre-cognitive conflict induced by only a discrepant event exerted a direct effect on post-cognitive conflict induced by a discrepant event and an alternative hypothesis. Post-cognitive conflict had a direct effect on conceptual change. Pre-anxiety decreased after presenting an alternative hypothesis. Pre-anxiety influenced post-anxiety, and this influenced on conceptual change via effort negatively. Attention had a direct effect as well as an indirect effect on conceptual change via effort. These results suggest that the strategy presenting both a discrepant event and an alternative hypothesis to students in concept learning could facilitate conceptual change by inducing more cognitive conflict or active participation of students through the decrease of anxiety than that presenting a discrepant event only.

A Study on the Exhibition and Convention Visitors' Satisfaction Level and on the Participating Companies' Perception on the Performance - Centered on the Busan International Travel Fair - (전시·컨벤션 참관객 만족도와 참여업체 성과인식에 관한 연구 - 부산국제관광전을 중심으로 -)

  • Lee, Jong-Ho
    • Management & Information Systems Review
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    • v.34 no.2
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    • pp.171-191
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    • 2015
  • This study is about the exhibition and convention visitors' satisfaction level and the participating companies' perception on the performance. The two topics were approached with integrated model. Accordingly, this study examined how service quality and experiential quality affect exhibition and convention visitors' satisfaction level and the participating companies' perception on the performance, and how the correlation between exhibition and convention visitors' satisfaction level and the participating companies' perception on the performance is affected. The result demonstrates that the quality of experience exerts positive effect on the visitors' sense of satisfaction(Hypothesis 3), while service quality is not statistically significant when it comes to the visitors' satisfaction(Hypothesis 1). When the correlation between service quality and experiential quality, and the participating companies' perception on the performance is examined, service quality exerts positive effect on the participating companies' perception on the performance(Hypothesis 2), while experiential quality is not statistically significant on the participating companies' perception on the performance(Hypothesis 4), When the correlation between exhibition and convention visitors' satisfaction level and the participating companies' perception on the performance is examined, it was shown that positive effect is exerted just like the results of the previous studies(Hypothesis 5), lastly, correlation between participating companies' perception on the performance, companies' satisfaction and company loyalty was examined. In case of the participating companies' perception on the performance, it exerts positive effect on the companies' satisfaction(Hypothesis 6), while company loyalty is not statistically significant (Hypothesis 7). In case of companies' satisfaction, it exerts positive effect on the company loyalty (Hypothesis 8). The results of this study will provide help to increase overall understanding of the exhibition and convention visitors' satisfaction level and the participating companies' perception on the performance, and to provide important implications for the development of strategy for exhibition and convention's vitalization.

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Clinical efficacy and mechanism of probiotics in allergic diseases

  • Kim, Ha-Jung;Kim, Hyung Young;Lee, So-Yeon;Seo, Ju-Hee;Lee, Eun;Hong, Soo-Jong
    • Clinical and Experimental Pediatrics
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    • v.56 no.9
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    • pp.369-376
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    • 2013
  • A complex interplay between genetic and environmental factors partially contributes to the development of allergic diseases by affecting development during prenatal and early life. To explain the dramatic increase in the prevalence of allergic diseases, the hygiene hypothesis proposed that early exposure to infection prevented allergic diseases. The hygiene hypothesis has changed to the microbial hypothesis, in which exposure to microbes is closely linked to the development of the early immune system and allergic diseases. The intestinal flora may contribute to allergic disease through its substantial effect on mucosal immunity. Based on findings that exposure to microbial flora early in life can change the Th1/Th2 balance, thus favoring a Th1 cell response, probiotics may be beneficial in preventing allergic diseases. However, evidence from clinical and basic research to prove the efficacy of probiotics in preventing allergy is lacking. To date, studies have yielded inconsistent findings on the usefulness of probiotics in allergic diseases. It is difficult to demonstrate an exact effect of probiotics on asthma, allergic rhinitis, and food allergy because of study limitations, such as different first supplementation period, duration, different strains, short follow-up period, and host factors. However, many studies have demonstrated a significant clinical improvement in atopic dermatitis with the use of probiotics. An accurate understanding of the development of human immunity, intestinal barrier function, intestinal microbiota, and systemic immunity is required to comprehend the effects of probiotics on allergic diseases.

A Study on The Extent of Alienation Revealed among A Group of Aged People in Seoul City (서울시내 일부 노인들의 소외정도에 관한 조사연구)

  • 김행자
    • Journal of Korean Academy of Nursing
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    • v.4 no.2
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    • pp.32-43
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    • 1974
  • A steady increase in the aged population poses a great challenge to nurses with their diversities of health care needs, especially of psychological nature, such as an alienation problems among the aged. The purpose of this study is to examine the nature of alienation problems among the aged in urban areas to provide basic informations for a better understanding of aged people. In this study, the investigator has tried to identify causes of alienation in the aged, and to determine the extent of alienation in relation to sex, family structure, religion, economic status and participation in social activities. The survey was done during the period from the last part of August to the end of September 1973. After a day's training, 10 interviewers have interviewed 210 stratified random samples of people over the age of 65 residing in Seoul with the free-ended questionnaire prepared by the investigator. The result of the study was tested by Critical Ratio. Following Hypothesis have guides formulation of the study: I. The extent of alienation in old man would be higher than in old woman, II. The extent of alienation in the aged who live alone would be higher than those living with their family. III. The extent of alienation in the aged who have no spouse would be higher than who live with their spouse. IV. The extent of alienation in the people without religious beliefs would be higher than the people with religious biles. V. The extent of alienation in the aged would be higher in proportion to decreased level of their economic productivity. Ⅵ. The extent of alienation in the aged who do not participate in social activities would be higher than that of the aged who actively participate. The analytic results of the study are as fellows: 1. The extent of alienation in woman was revealed higher than that of man by showing significant difference at P〈0.01 level. (CR=3.66) Accordingly hypothesis I was denied. 2. The extent of alienation in the aged wile live alone was revealed higher than that of the aged who live with their family by showing a significant difference at P<0.01 level. (CR=7.31) So hypothesis II was supported. 3. The extent of alienation of the aged who have no spouse was revealed higher than that of the aged who live with their spouse at the significant level of P <0.01. CR=4.65) Accordingly hypothesis III was supported, 4. There was no significant difference in the extent of alienation between the people with and-without religion. Thus hypothesis IV was rejected. 5. The extent of alienation in the aged was found to be higher in proportion to decreased level of their economic ability. a. The aged with greatest income showed least alienation b. The aged with no income had a greater extent of alienation than the aged with minimal income by showing significant difference at P <0.01 level . (CR=4.82) c. The difference between the greatest income group and the minimal income group was. found to be less significant than the difference between minimal income group and the-people without income. Thus hypothesis V was positively supported. 6. The extent of alienation in the aged who do not participate in social activities was higher than that of the aged who actively participate. (P <0.01, CR=6.24) According1y hypothesis Ⅵ was supported.

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