• PNF and Movement
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• 제17권3호
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• pp.487-497
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• 2019

Purpose: This tutorial review investigated the effect of prior fatigue and passive stretches on eccentric contraction-induced muscle injuries, as well as the underlying mechanisms of eccentric contraction-related injuries. Methods: Contraction-induced muscle damage is the most common disabling problem in sports and routines. The mechanisms underlying the pathology and prevention of muscle damage lessened by prior fatigue or stretches are critical in assessing musculoskeletal injuries. Even though there are treatments to reduce eccentric contraction-induced muscle injuries, fatigue negatively influences them. Therefore, we reviewed previous studies on eccentric contraction-induced muscle injuries with prior treatments using the MEDLINE and PubMed databases. Results: Prior passive stretching had a preventative and therapeutic effect, but prior lengthening contractions did not. On the other hand, prior isometric contractions involving relatively small forces may not provide a sufficient stimulus to induce protection. As a result, high force isometric contractions may be necessary. The studies supported the positive effects of prior fatigue, concluding that it was a factor in determining the amount of damage caused by eccentric exercise. This was due to a reduction in force and increased temperature. Studies that did not support the positive effects of prior fatigue concluded that a shift in optimal length to a longer length and reduced energy absorption during lengthening are evidence that fatigue is not related to muscle injuries induced by lengthening. Conclusion: The variability of the experiment models, conditions, muscles, and treatment methods make it necessary to interpret the conditions of previous studies carefully and draw conclusions without making direct comparisons. Thus, additional studies should be carefully conducted to investigate the positive effect of fatigue on lengthening.

• Journal of Korea Trade
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• 제27권5호
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• pp.91-112
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• 2023

Purpose - This study empirically investigates how the effects of localized knowledge spillovers on technology adoption are conditional on the organizational capabilities of potential adopters. Design/methodology - The empirical model utilized in this study examines how the presence of prior adopters of advanced manufacturing technologies affects a plant's technology adoption decision differently based on its organizational capabilities, measured by plant size and plant status (single-plant firm vs. multi-plant firm). Moreover, this study investigates how the scope of knowledge spillovers from prior adopters, both in terms of geographical and functional proximities, differ for plants with different organizational capabilities. Findings - The main findings of this study are as follows: 1. Although plants with lower organizational capabilities are less likely to adopt advanced technologies, such plants receive greater marginal benefits from knowledge spillovers from prior adopters in their region. 2. Plants with greater organizational capabilities can benefit from knowledge spillovers from a wider set of prior adopters. In other words, while plants with lower organizational capabilities tend to benefit from knowledge spillovers from "similar" and "local" adopters, plants with greater organizational capabilities can also benefit from knowledge spillovers from "not-too-similar" or are geographically distant prior adopters. Originality/value - While existing studies mainly focus on the effects of the various kinds of regional agglomeration, few studies investigate localized knowledge spillovers in technology adoption. Moreover, no prior studies have explored how the effects of knowledge spillovers on technology adoption depend on a plant's organizational capabilities and how the scope of knowledge spillovers differs for plants with different organizational capabilities. This study is the first to empirically investigate this topic.

• 유통과학연구
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• 제12권5호
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• pp.15-26
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• 2014

Purpose - This study addresses an acquisition's impact on a firm's strategic relationship based on findings of existing academic studies and theoretical assertions. Through examining existing research results and theoretical grounds for an acquisition's impact on various stakeholders, this study indirectly approaches the impact on stakeholders including alliance partners. Research design, data, and methodology - This research identified a variety of related theoretical foundations and empirical studies. Research objectives of prior studies mainly focused on merging firms and direct participants of acquisition activity. In addition, academic attention on the impact on rival firms has recently been growing. However, little research on alliance partners was found. Prior studies simultaneously employed event study methodology and cross-sectional analysis to make further theoretical contributions. Results and Conclusions - Based on the findings of prior studies, this research proposed a complementary research model for future academic inquiry into the impact of an acquisition on an alliance partner's return and for predicting an acquisition announcement's effect on alliance partners.

• Communications for Statistical Applications and Methods
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• 제15권1호
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• pp.13-26
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• 2008

Inference on the present data will be more reliable when the data arising from previous similar studies are available. The data arising from previous studies are referred as historical data. The power prior is defined by the likelihood function based on the historical data to the power $a_0$, where $0\;{\le}\;a_0\;{\le}\;1$. The power prior is a useful informative prior for Bayesian inference such as model selection and model comparison. We utilize the historical data to perform multiple comparison in the one-way ANOVA model. We demonstrate our results with some simulated datasets under a simple order restriction between the treatments.

• 아동학회지
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• 제34권1호
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• pp.21-34
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• 2013

The purposes of this study were (1) to investigate the differences in the level of children's knowledge and reasoning skills due to the sloping phenomenon according to their ages and the types of tasks they were asked to perform, and (2) to investigate whether children's prior knowledge is changed to post knowledge through their reasoning. A total of 120 subjects, forty from each of the age groups 4, 6 and 8 were selected for the study. The major findings are presented below : 8-year old children showed higher levels of prior knowledge than 6-year old children. The prior knowledge level of the "size" task was higher than that of the "weight" task. 6-and 8-year old children showed higher levels of reasoning than 4-year old children. The reasoning level of the "size" task was higher than that of the "weight" task. 6-and 8-year old children showed higher levels of post knowledge than 4-year old children. However, there was no difference in children's post knowledge according to task difference. Through the different types of reasoning involved in the children's performances of the two tasks, changes in the prior knowledge of the sloping phenomenon were observed among all age groups.

• 예술경영연구
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• 제54호
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• pp.59-93
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• 2020

디지털기술의 발달로 소비자들은 어느 때보다 상품에 관한 해박한 사전지식을 보유하게 되었다. 뮤지컬과 같은 서비스재는 무형성, 비분리성, 이질성 등으로 인해 사전지식 추구 경향이 더욱 강하게 나타난다. 공연예술 분야의 선행연구들은 관람객의 사전지식이 관람만족과 구전의향에 긍정적인 영향을 준다는 사실을 밝혔으나 최근에는 사전지식이 많은 경우 오히려 상품평가에 부정적 영향을 미친다는 주장도 있다. 이에 본 연구에서는 뮤지컬사전지식이 어떤 조건에서 관람만족과 구전의향을 높이는지 확인하고자 했다. 이를 위해서, 뮤지컬사전지식이 관람만족을 매개로 구전의향을 높이는 매개모형을 설정하였다. 그리고 이 매개경로를 조절하는 변수로서 트랜스포테이션을 도입하여 트랜스포테이션 수준에 따라 관람만족과 구전의향이 변화하는지를 검증하였다. 스토리로의 몰입과 동일시를 설명하는 개념인 트랜스포테이션을 도입한 이유는 뮤지컬 구성요소로서 스토리의 중요성이 크다는 선행연구결과를 반영한 것이다. 조절된 매개분석 결과, 뮤지컬사전지식이 관람만족을 통해 구전의향에 영향을 주는 매개경로는 트랜스포테이션에 의해 조절됨을 알 수 있었다. 이러한 결과를 통해 사전지식으로 무장한 관람객들을 만족시키기 위해서는 질 높은 뮤지컬스토리가 중요하다는 사실을 최초로 실증하였다는 점에 본 연구의 의의가 있다.

• 응용통계연구
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• 제14권1호
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• pp.161-175
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• 2001

메타분석(Meta-analysis)은 서로 독립적으로 연구되어진 결과들을 전체적인 하나의 결과로 도출하기 위해 사용되어지는 통계적 방법이다. 이러한 통계적 방법을 설명할 모형으로는 선택모형(selection model)을 포함한 계층적 모형(hierarchical model)을 사용하며, 이러한 모형들은 베이지안 메타분석에 유용한 것으로 알려져 있다. 그러나, 메타분석의 자료들은 일반적으로 출판편의(publication bias)를 갖고 있으므로 이를 극복하고자 가중함수(weight function)를 이용하여 분포함수를 새롭게 정의하여 사용한다. 최근에 Silliman(1997)은 계층적 모형(hierarchical model)에 가중함수를 첨부한 계층적 선택모형(hierarchical selection model)을 정의하고 모수적 베이지안 방법을 제시하였다. 본 연구에서는 미관측된 연구효과에 디리슈레 과정 사전분포(Dirichlet process prior)를 적용한 준모수적 계층적 선택모형(semiparametric hierarchical selection models)을 소개한다. 여기서 제시된 준모수적 계층적 선택모형을 베이지안 방법으로 추정하기 위하여 마코프 연쇄 몬테칼로(Markov chain Monte Carlo)방법을 이용한다. 제시된 방법을 적용하기 위하여 실제 자료(Johnson, 1993)인 충치를 예방하기 위한 두 가지의 예방약의 효과에 대한 차이를 비교하기 위해 얻어진 12개의 연구를 이용하여 메타분석을 한다.

• Communications for Statistical Applications and Methods
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• 제30권3호
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• pp.311-330
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• 2023

The present work describes simulation studies to compare the performances in terms of averaged mean squared error of bayesian wavelet shrinkage methods in estimating component curves from aggregated functional data. Five bayesian methods available in the literature were considered to be compared in the studies: The shrinkage rule under logistic prior, shrinkage rule under beta prior, large posterior mode (LPM) method, amplitude-scale invariant Bayes estimator (ABE) and Bayesian adaptive multiresolution smoother (BAMS). The so called Donoho-Johnstone test functions, logit and SpaHet functions were considered as component functions and the scenarios were defined according to different values of sample size and signal to noise ratio in the datasets. It was observed that the signal to noise ratio of the data had impact on the performances of the methods. An application of the methodology and the results to the tecator dataset is also done.

• Journal of the Korean Data and Information Science Society
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• 제28권4호
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• pp.875-888
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• 2017

The Rayleigh distribution has been commonly used in life time testing studies of the probability of surviving until mission time. We focus on a reliability function of the Rayleigh distribution and deal with prior distribution on R(t). This paper is an effort to obtain Bayes estimators of rayleigh distribution with three different prior distribution on the reliability function; a noninformative prior, uniform prior and inverse gamma prior. We have found the Bayes estimator and predictive density function of a future observation y with each prior distribution. We compare the performance of the Bayes estimators under different sample size and in simulation study. We also derive the most plausible region, prediction intervals for a future observation.

• Journal of the Korean Statistical Society
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• 제34권4호
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• pp.331-344
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• 2005

Inference on current data could be more reliable if there exist similar data based on previous studies. Ibrahim and Chen (2000) utilize these data to characterize the power prior. The power prior is constructed by raising the likelihood function of the historical data to the power $a_o$, where $0\;{\le}\;a_o\;{\le}\;1$. The power prior is a useful informative prior in Bayesian inference. However, for model selection or model comparison problems, the propriety of the power prior is one of the critical issues. In this paper, we suggest two joint power priors for the power law process and show that they are proper under some conditions. We demonstrate our results with a real dataset and some simulated datasets.