• 제목/요약/키워드: hypothesis

검색결과 6,321건 처리시간 0.033초

제품개선을 위한 부품통합 설계가설에 대한 연구 (A study on the design hypothesis of integrated part for product improvement)

  • 최준호;이건상
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2008년도 추계학술대회A
    • /
    • pp.1176-1180
    • /
    • 2008
  • This paper represents a study on design hypothesis to improve properties of a product. The functional requirements and function structure of various technical products are analysed. From the above analysis we could formulate one hypothesis. This hypothesis also satisfies basic rules clarity, simplicity and safety that are required in all design cases. The hypothesis says that functional requirements is refined to improve and if there are components which have the same function, they can be integrated into one component and improved. A one-handed faucet was developed by applying the above hypothesis to a two-handed faucet. The design of heat exchange tester was be improved successfully through the hypothesis.

  • PDF

AESA 레이더 최대탐지거리의 통계적 접근 (Statistical Approach for AESA Radar Maximum Detection Range)

  • 탁대석;신경수
    • 시스템엔지니어링학술지
    • /
    • 제15권1호
    • /
    • pp.43-50
    • /
    • 2019
  • Statistical hypothesis tests are important for quantifying answers to questions about samples of data. The Step Process of Statistical Hypothesis Testing; state the null hypothesis, State the alternate hypothesis, State the alpha level, Find the z-score associated with alpha level, Find the test statistic using this formula, If the calculated t distribution value from the data is larger than the t distribution value of alpha level, then you are in the Rejection region and you can reject the Null Hypothesis with ($1-{\alpha}$) level of confidence.

임상연구방법론에서 귀무가설과 대립가설, 귀류법에 대한 고찰과 한방이비인후과에서 베이지안 통계학의 활용 (A Study on Null Hypothesis and Alternative Hypothesis, Reduction to Absurdity and Application of Bayesian Statistics in Korean Medicine Otolaryngology)

  • 남승표;배재민;권강
    • 한방안이비인후피부과학회지
    • /
    • 제32권4호
    • /
    • pp.41-61
    • /
    • 2019
  • Background : The current medical statistics used in clinical research are the results of Fisher's significance test and the Neyman-Pearson hypothesis test, which were combined by psychologists. Also, in the philosophical background, it is related to Popper's falsificationism based hypothesis-deductive method and reduction to absurdity. Objectives : This study was designed to find complementary and alternative methods of null hypothesis and alternative hypothesis used for the clinical research methodology of Korean medicine otolaryngology. Methods : The body of this paper was divided into seven part. These are historical background, hypothesis test, hypothesis test method used in the design of clinical study, falsificationism and reduction to absurdity, problem and alternative method of the Neyman-Pearson hypothesis test, diagnosis example of sinusitis differentiation syndromes by Bayesian statistics. Through this process, we found out problems of frequentist statistics and suggested alternative methods. Result & Conclusion : As a solution to the problems of the null hypothesis and the alternative hypothesis, there are effects size, confidence interval, Bayesian statistics and Lakatos methodology of scientific research programmes.

'상풍즉오풍 상한즉오한(傷風則惡風 傷寒則惡寒)'에 대한 소고(小考) (A study on 'If the wind damage people, they feel aversion to wind. If the cold damage people, they feel aversion to cold.(상풍즉오풍 상한즉오한(傷風則惡風 傷寒則惡寒))')

  • 김상운
    • 대한한의진단학회지
    • /
    • 제18권1호
    • /
    • pp.33-43
    • /
    • 2014
  • Objective I would like to identify when 'If the wind damage people, they feel aversion to wind. If the cold damage people, they feel aversion to cold.(傷風則惡風 傷寒則惡寒)' has appeared and what does this hypothesis have affected. I also researched future scholars' opinions and their criticism on this hypothesis. Methods: 1. Among the books which are related to Cold damage according to the age, books which have original text that has a relationship with this hypothesis were elected. Total of 30 books were elected, and their original text was extracted and analyzed. Results 1. This hypothesis appeared first on Hwalinseo(活人書) in the Song Dynasty, and had lots of impact on future generations. 2. After passing Song, Yuan, and Ming Dynasty, there were some opinions appeared which criticized part of this hypothesis. Dongeuibogam(東醫寶鑑) also tried to correct this hypothesis. 3. Bang Yu-Jip(方有執) of Ming Dynasty straightly opposed this hypothesis on Sanghanronjobyeon(傷寒論條辨)for the first time. It had huge influence in the Qing Dynasty and lots of scholars suggested that this hypothesis lacks persuasion. 4. Just like Qing Dynasty, this hypothesis is not accepted in the books of modern ages. Conclusion This hypothesis appeared in the Song Dynasty for the first time and had lots of influence, but some counter arguments had appeared as time passed, and during Qing Dynasty, this hypothesis lost its creditibility with lots of criticism.

정신분열병과 면역학적 이상 (Schizophrenia and Immunological Abnormalities)

  • 정희연;김용식
    • 생물정신의학
    • /
    • 제15권3호
    • /
    • pp.152-174
    • /
    • 2008
  • There have been vast amount studies regarding immunologic dysregulation in schizophrenia. The mechanism of immune pathogenesis in schizophrenia still is unclear, even though various immune dysfunction have been reported. We endeavored to report on two major hypothesis on immunologic dysregulation in schizophrenia, the infection hypothesis and autoimmune hypothesis. We went on to focus on the autoimmune hypothesis, which has received the most attention over the years. We explored the accumulated data and the rational behind the autoimmune hypothesis and the implications of the autoimmune hypothesis for future research in the pathogenesis of schizophrenia.

  • PDF

The Return Generating Process of Corporate Bonds based on Credit Ratings

  • 정원길
    • Journal of the Korean Data and Information Science Society
    • /
    • 제14권4호
    • /
    • pp.805-815
    • /
    • 2003
  • This study examines two hypothesis regarding return generating process of corporate bonds: the trading day hypothesis and calendar day hypothesis. To differentiate two hypothesis ANOVA(analysis of variance) and regression analysis were used. If the statistical result can not reject calendar day hypothesis, it implies that there is weekend effect. The statistical result didn't support any particular hypothesis for the period of September 7th, 1999 through December 31, 2002. However, corporate bonds were supporting calendar day hypothesis for the period of October 9, 2000 through December 31, 2002. The result indicates that the Korean corporate bond market got through the impact of IMF.

  • PDF

Dual-Strategy Hypothesis모델과 보행 시작시의 동작분석 고찰 (The Dual-Strategy Hypothesis Whereby Motor Control Is Assessed From a Position of Quiet Stance)

  • 김형동;박래준
    • The Journal of Korean Physical Therapy
    • /
    • 제14권3호
    • /
    • pp.418-432
    • /
    • 2002
  • 본 연구의 목적은 다음과 같이 네 가지이다. 첫째, dual-strategy hypothesis 모델의 이론적인 배경을 서술한다. 둘째, 보행시작 시 (Gait Initiation)와 장애물 보행시작 (Stepping over obstacles)시의 motor task를 dual-strategy hypothesis 모델의 관정에서 서술한다. 셋째, 파킨슨씨 환자군과 뇌졸증 환자군을 이 모델의 관점에서 서술한다. 마지막으로, dual strategy hypothesis모델의 임상적용 가능성에 대해서 간단히 서술하는 것이다.

  • PDF

기업 SNS 내 소비자의 상호작용과 몰입이 소비자의 애착에 미치는 영향에 관한 연구 (A Study on the Effect of the Interaction and Flow of Consumers within the Company SNS on the Consumers' Affection)

  • 김한주
    • 경영과정보연구
    • /
    • 제34권3호
    • /
    • pp.231-250
    • /
    • 2015
  • 본 연구는 기업 SNS 내 소비자의 상호작용과 몰입이 소비자의 애착에 미치는 영향에 관한 연구로 이론적 배경을 바탕으로 하여 실증분석을 통해 검증하였으며, 연구결과를 토대로 연구결과를 요약하면 다음과 같다. 첫째, 콘텐츠 이용 동기 측면과 상호작용성과의 관계를 살펴보면 다음과 같다. 상호연대감(가설1-1), 영향력(가설1-2), 연결성(가설1-3), 반응성(가설 1-4) 모두 상호작용에 정(+)의 영향을 미치는 것으로 나타났다. 둘째, 콘텐츠 이용 동기 측면과 몰입과의 관계는 다음과 같다. 상호연대감(가설2-1), 영향력(가설2-2), 연결성(가설2-3)이 몰입에 정(+)의 영향을 미치는 것으로 나타났다. 반면, 반응성(가설 1-4)은 몰입에는 통계적으로 유의하지 않은 것으로 나타났다. 셋째, 콘텐츠 특성과 상호작용과의 관계는 오락성(가설3-1),정보성(가설 3-2)모두 상호작용성에 정(+)의 영향을 미치는 것으로 나타났다. 넷째, 콘텐츠 특성과 몰입과의 관계를 살펴보면 정보성(가설4-2)만이 몰입에 정(+)의 영향을 미치는 반면에 오락성은 몰입에 통계적으로 유의하지 않은 것으로 나타났다. 마지막으로 상호작용과 몰입 그리고 애착과의 관계는 다음과 같다. 상호작용성과 몰입과의 관계(가설 5)는 통계적으로 유의하지 않은 것으로 나타난 반면에 상호작용성(가설6)과 몰입(가설7)은 모두 애착에 정(+)의 영향을 미치는 것으로 나타났다. 이러한 결과를 바탕으로 기업 SNS를 이용하는 실무자에게 다양한 시사점과 의의를 제시 하였다.

  • PDF

Testing the Liquidity Hypothesis in the Korean Retail Firms

  • Kim, Sang-Su;Lee, Jeong-Hwan
    • 유통과학연구
    • /
    • 제15권5호
    • /
    • pp.29-38
    • /
    • 2017
  • Purpose - Prior theories predict a negative correlation between stock liquidity and dividend payout propensity. We test this hypothesis by examining the sample Korean retail firms. Research design, data, and methodology - We construct four different types of stock liquidity measures and investigate how these stock liquidity variables affect dividend payout propensity by employing the logit regression model. The retail firms listed in the KOSPI and KOSDAQ markets are analyzed from 1990 to 2015. Results - Our estimation results support the liquidity hypothesis if we adopt the stock turnover rate as the stock liquidity measure, particularly for the retail firms listed in the KOSPI markets and for non-conglomerate firms. Yet, our estimation results adopting the illiquidity measure of Amihud (2002), the proportion of non-trading day, and the volume of trading do not support the liquidity hypothesis. Conclusions - Our findings provide mixed results for the validity of stock liquidity hypothesis, which enriches the existing literature. In terms of turnover rate, the stock liquidity hypothesis holds robustly. Yet, we are not able to find any empirical evidence supporting the hypothesis if we use the other three measures of stock liquidity.

EEG Correlation Patterns of Hypothesis-Generating in Undergraduate Students' Generation of Scientific Knowledge

  • Kwon, Yong-Ju;Jeong, Jin-Su;Jin, Seung-Hyun
    • 한국과학교육학회지
    • /
    • 제24권4호
    • /
    • pp.722-730
    • /
    • 2004
  • The purpose of this study was to test the notion that the inter-individual difference in hypothesis-generating is presumably detected by differentiating subjects' EEG correlation patterns of the prefrontal lobes. To test the notion of the inter-individual difference by EEG analysis, eight healthy undergraduate volunteers' EEG signals on the prefrontal lobes were recorded during hypothesis-generating and resting with eyes-closed condition. Their EEG signals were analyzed by time durations and transformed into correlation patterns. The results showed that subjects' EEG correlation patterns during hypothesis-generating were significantly different among individuals. In addition, the EEG correlation patterns were decreased during hypothesis-generating thinking. Furthermore, subject's EEG correlation showed a fluctuationpattern through-out hypothesis-generating, which is presumably caused by the difference of subjects' thinking activities in hypothesis-generating. This study also suggests a possibility that student's scientific thinking ability and the difficulty of scientific knowledge generating may be measured by the analysis of subject's EEG correlation pattern of the prefrontal lobes.