• 한국수학교육학회지시리즈A:수학교육
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• 제48권3호
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• pp.353-358
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• 2009

The article discusses the independence concept occurring in the learning of probability. The author does not distinguishes the independence in the events from the independence in the trials. Instead, the author suggests the physico-empirical independence and the logico-mathematical independence to distinguish between the two concepts.

• 대한수학교육학회지:학교수학
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• 제10권3호
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• pp.319-337
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• 2008

일상어로서의 언어적 개념에 의해 형성된 독립에 대한 직관은 수학에서의 독립성에 대한 새로운 개념체계를 확립하는 데 있어 도움을 주거나 방해를 한다. 다시 말해 이러한 갈등을 동반하는 직관은 독립성을 설명을 설명하는데 원동력이 되기도 하나 때로는 오개념을 유발하는 장애요인이기도 하다. 본 논문의 목적은 이러한 원동력이 되는 직관과 장애가 되는 직관을 구분하여 학생들이 직관을 바르게 사용하도록 하는 데 있다. 이로써 독립의 언어적 해석의 개입으로 인해 발생하는 잘못된 직관에 의한 오개념을 오히려 드러내어 가르칠 필요가 있음을 제안하였다. 또한 시행의 독립성과 사건의 독립성의 명확한 구분이 필요하다는 것을 제안하였으며, 복원추출과 비복원 추출이 사건의 독립과 종속의 대표적인 예로 특정화되어서는 안 되는 것을 반례를 통해 보였다. 본 논문에서의 직관의 분석은 Fischbein이 분류한 직관을 바탕으로 하였으며 독립성의 개념에 적용되는 직관을 구체적으로 Fischbein의 직관과 대응시켜 분석하였다.

• 대한산업공학회지
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• 제1권1호
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• pp.99-103
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• 1975

A procedure for the test of independence of the observations and the null distribution are studied for a waiting-time distribution of the number of Bernoulli trials required to obtain a preassigned number of successes under Markov dependence. Selected critical values for the test statistic are tabulated.

• Journal of the Korean Data and Information Science Society
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• 제10권2호
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• pp.279-288
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• 1999

통계자료분석에서 많이 다루는 이 원자료(binary data)는 고전적인 이항분포모형에서 가정하는 시행간 독립성이 결여된 경우가 대부분이므로 그 자료에 고전적 이항분포이론을 그대로 적용할 경우 잘못된 분석 결과를 얻게 된다. 따라서, 최근에 이러한 가정이 타당하지 않은 경우에 대한 새로운 확률분포모형이 많이 개발되었다. 본 논문에서는 이중 한 일반화 이항분포모형을 소개하고, 그 모형에서 정의된 시행간 종속성 규정모수의 두 가지 추정량의 특성을 모의실험을 통하여 비교하여 본다.

• 한국임상약학회지
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• 제26권2호
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• pp.181-186
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• 2016

Background: There has been on increasing emphasis on the importance of monitoring the safety of participants in a clinical trial to protect patients and maintain the integrity of the trial. The independent data monitoring committee (IDMC) has become common component of randomized clinical trials in recent years. Methods: It is important to consider the implications of different approaches that are being used in various countries. IDMC guidelines in Korea, US, and Europe were reviewed and compared to provide the objective, composition and operation of IDMC in detail. Results: IDMC is a group of experts in related subject are as who perform interim data monitoring to make a recommendation to the sponsor or organizer regarding appropriateness of trial continuation and the need for modifications of the trial. Independence of IDMC is preferred in order to minimize influence of factors unrelated to scientific, medical and ethical considerations that should underlie decision-making. Conclusion: IDMC has become an increasingly important component of clinical trials in recent years. Practical operating procedures need to be developed considering the future regulatory status of data monitoring committees.

• 한국임상수의학회지
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• 제31권4호
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• pp.288-292
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• 2014

A critical assumption of the standard sample size calculation is that the response (outcome) for an individual patient is completely independent to that for any other patient. However, this assumption no longer holds when there is a lack of statistical independence across subjects seen in cluster randomized designs. In this setting, patients within a cluster are more likely to respond in a similar manner; patient outcomes may correlate strongly within clusters. Thus, direct use of standard sample size formulae for cluster design, ignoring the clustering effect, may result in sample size that are too small, resulting in a study that is under-powered for detecting the desired level of difference between groups. This paper revisit worked examples for sample size calculation provided in a previous paper using nomogram to easy to access. Then we present the concept of cluster design illustrated with worked examples, and introduce design effect that is a factor to inflate the standard sample size estimates.

• 대한한의학회지
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• 제36권4호
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• pp.8-18
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• 2015

Objectives: There have been several studies evaluated effect of electroacupuncture (EA) on spasticity but most studies could not assess spasticity quantitatively because they used clinical rating scales for assessment spasticity. The objective of this study is to evaluate effect of EA on poststroke spasticity quantitatively using tendon reflex (T-reflex). Methods: 29 stroke patients with upper extremity spasticity were randomized to EA group and control group. The EA group received combined EA and rehabilitation therapy 5 times a week for 3 weeks. Acupuncture treatment was given at Jian Yu (LI 15), Qu Chi (LI 11), Shao Hai (HT 3), Wai Guan (TE 5), He Gu (LI 4), Lie Que (LU 7), Hou Xi (SI 3) of the affected side, 30 minutes of electrical stimulation with a frequency of 40/13 Hz was applied at Qu Chi (LI 11), He Gu (LI 4). The control group received only rehabilitation therapy. The efficacy of treatment was assessed using T-reflex latency and amplitude, modified Ashworth scale (MAS) of biceps brachii, brachioradialis and triceps brachii. Fugl-Meyer motor function assessment (FMA) and functional independence measure (FIM) were also measured to assess motor function and functional independence. All outcomes were measured before treatment, immediately after 3 weeks of treatment and 1 week after 3 weeks of treatment. Results: No statistically significant differences were found in outcomes including T-reflex between the study groups except for FIM values immediately after 3 weeks of treatment (p=0.037). Conclusions: These results suggest that 3 weeks of EA does not reduce poststroke upper extremity spasticity electrophysiologically and clinically. However, small sample sizes and contradictory tendency between results from T-reflex and those from MAS require cautious judgement on interpretation of the results. A larger, well-designed clinical trials for quantitative evaluation of effect of EA on poststroke spasticity will be needed.

• Journal of Korean Neurosurgical Society
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• 제57권5호
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• pp.342-349
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• 2015

Background : Higher reperfusion rates have been established with endovascular treatment for acute ischemic stroke patients. There are limited data on the comparative performance of mechanical thrombectomy devices. This study aimed to analyse the efficacy and safety of the stent retriever device (Solitaire stent) by comparing procedure time, angiographic outcome, complication rate and long term clinical outcome with previous chemical thrombolysis and mechanical thrombectomy using penumbra system. Method : A retrospective single-center analysis was undertaken of all consecutive patients who underwent chemical thrombolysis and mechanical thrombectomy using Penumbra or Solitaire stent retriever from March 2009 to March 2014. Baseline characteristics, rate of successful recanalization (modified Thrombolysis in Cerebral Infarction score 2b-3), symptomatic intracerebral hemorrhage, procedure time, mortality and independent functional outcomes ($mRS{\leq}2$) at 3 month were compared across the three method. Results : Our cohort included 164 patients, mechanical thrombectomy using stent retriever device had a significant impact on recanalization rate and functional independence at 3 months. In unadjusted analysis mechanical thrombectomy using Solitaire stent retriever showed higher recanalization rate than Penumbra system and chemical thrombolysis (75% vs. 64.2% vs. 49.4%, p=0.03) and higher rate of functional independence at 3 month (53.1% vs. 37.7% vs. 35.4%, p=0.213). In view of the interrelationships between all predictors of variables associated with a good clinical outcome, when the chemical thrombolysis was used as a reference, in multiple logistic regression analysis, the use of Solitaire stent retriever showed higher odds of independent functional outcome [odds ratio (OR) 2.62, 95% confidence interval (CI) 0.96-7.17; p=0.061] in comparison with penumbra system (OR 1.57, 95% CI 0.63-3.90; p=0.331). Conclusion : Our initial data suggest that mechanical thrombectomy using stent retriever is superior to the mechanical thrombectomy using penumbra system and conventional chemical thrombolysis in achieving higher rates of reperfusion and better outcomes. Randomized clinical trials are needed to establish the actual benefit to specific patient populations.

• 한국운동역학회지
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• 제29권3호
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• pp.157-166
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• 2019

Objective: This study examined the effects of stimulating fingertip temperature on the patterns of force sharing and stability properties during multi-finger force production tasks. Method: 9 adult subjects (male: 3, female: 6, age: $26.11{\pm}4.01yrs$, height: $169.22{\pm}5.97cm$, weight: $61.44{\pm}11.27kg$) participated in this study. The experiment consisted of three blocks: 1) maximal voluntary contraction (MVC) task, 2) single-finger ramp task to quantify enslaving (i.e., unintended force production by non-task fingers), and 3) 12 trials of multi-finger steady-state force production task at 20% MVC. There were three temperature conditions including body-temperature (i.e., control condition), $40^{\circ}C$, and $43^{\circ}C$, and the stimulation was given to the index finger only for all experimental conditions. Results: There were no significant differences in the MVC forces, enslaving, and the accuracy of performance during the steady-state task between the conditions. However, the share of stimulated index finger force increased with the index fingertip temperature, while the share of middle finger force decreased. Also, the coefficient of variation of both index and middle finger forces over repetitive trials increased with the index fingertip temperature. Under the framework of the uncontrolled manifold (UCM) hypothesis used to quantify indices of multi-finger synergies (i.e., stability property) stabilizing total force during the steady-state task, the two variance components within the UCM analysis increased together with the fingertip temperature, while no changes in the synergy indices between the conditions. Conclusion: The current results showed that fingertip temperature stimulation only to index finger does not affect to muscle force production capability of multi-finger, independence of individual fingers, and force production accuracy by the involvement of all four fingers. The effect of fingertip temperature on the sharing pattern and force variation may be due to diffuse reflex effects of the induced afferent activity on alpha-motoneuronal pools. However, the unchanged stability properties may be the reflection of the active error compensation strategies by non-stimulated finger actions.

• 척추신경추나의학회지
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• 제14권2호
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• pp.29-42
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• 2019

Objectives : This study aimed to review the effects of Daoyin exercise on stroke patients in clinical studies. Methods : In this study, we reviewed 11 electronic databases (CAJ, EMBASE, Cochrane Library, Web of Science, Pubmed, RISS, Dbpia, NDSL, KISTI, KISS, KMBASE) on October 27, 2019. We included only randomized controlled trials (RCTs) which evaluated the effect of Daoyin exercise on stroke patients. The methodological quality of the included studies was checked using the Cochrane risk of bias tool. Results : After screening the papers, eleven RCTs fulfilled the inclusion criteria. The results of the meta-analysis showed that Daoyin exercise improves the measurement value on the Fugl-Meyer Assessment, Modified Barthel Index and National Institutes of Health Stroke Scale in stroke patients. Conclusions : We concluded that Daoyin exercise has therapeutic effects in functional recovery and in enhancing the independence of daily living activities for stroke patients. However, the quality of the original articles was low and the number of papers included were few. Thus, to confirm these results, further well-designed RCTs should be conducted.