• 한방재활의학과학회지
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• 제20권4호
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• pp.105-130
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• 2010

Objectives : The purpose of this study was to assess the statistical methods errors used in the journal of Oriental Rehabilitation Medicine(JORM) and to identify the types of errors in statistical analysis. Methods : We reviewed quantitative articles that were published in the JORM from January 2005 through October 2009. Those were not used by statistical analysis such as literature studies, case study, review articles were not included in this analysis. A total of 296 articles was reviewed. We evaluated the adequacy and the validity of the statistical techniques with our checklist established be modified Lee's checklist, and three statistical evaluators assessed together to minimize bias. Results : Of the 222 articles, 213 were used in inferential and descriptive statistics. Of those 80% of articles adopting descriptive and inferential statistics were detected having statistical errors. One articles used 1.7 statistical method unit generally. Most frequently employed statistics were student t-test, one way ANOVA. pearson correlation analysis, Mann-whitney U test, paired t-test, and chi-square test in their order. However, most frequent statistics having errors were similar in order. The most common statistic errors were as follow: 1. absence of normality test, 2. misuse between paired test and unpaired test, 3. wrong choice of repeated measures analysis without consideration of time variables, 4, increase of Type I error by using inappropriate multiple test, 5. inappropriate application of discrete or categorical data instead of continuous data in correlation analysis, 6. poor consideration of basic consumption in chi-square test, 7. confusion between frequency comparison and average comparison, 8. mentioning the statistical technique without using it. Conclusions : We found various mistake or misuses in the applications of statistical methodologies in the articles published in the JORM. Careful consideration of statistical use and review from the specialist of statistics are warranted for improving the quality of JORM.

• Journal of Periodontal and Implant Science
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• 제27권1호
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• pp.179-189
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• 1997

Teeth mobility is an important part of a periodontal examination, because it represents a function of the persisting height of the alveolar bone and the width of the periodontal ligament. The purpose of this study was to evaluate clinical difference in teeth mobility after treatment with the modified Widman flap and the undisplaced flap in humans. Twenty males with moderate periodontal disease were selected. The severity of periodontal disease was evaluated with sulcular bleeding index, pocket depth and attachment level and tooth mobility was measured with Periotest(Siemens Co., Germany) at the initial examination, 1, 2, 4, 6, 8 and 12 weeks following the modified Widman flap and the undisplaced flap operation using the split-mouth technique. The relation of mobility to clinical parameters was statistically analyzed by multiple regression and the change of teeth mobility according to healing process by independent t-test using SPSS program. The results were as follows: 1. There was a strong relationship between the Periotest value(PTV) and attachment level. 2. The change of teeth mobility in both flap procedures was increased significantly at 1 week post-op. and was decreased to preoperative level at 4 weeks post-op, in modified Widman flap and at 6 weeks post-op. in undisplaced flap. 3. The change of teeth mobility in premolar teeth group in undisplaced flap compared to modified Widman flap was generally increased but these changes were not statistically significant. The changes of teeth mobility in molar teeth group in undisplaced flap was increased significantly at 2 weeks post-op.. 4. The change of teeth mobility following undisplaced flap was increased significantly compared to that of modified Widman flap at 2 weeks post-op.

• Steel and Composite Structures
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• 제45권4호
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• pp.605-619
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• 2022

The tensile behavior of the Thread-fixed One-side Bolt (TOB) at high temperatures was studied using the Finite Element Modeling (FEM) to explore the structural responses that could not be measured in tests. The accuracy of the FEM was verified using the test results from the failure mode, load-displacement curve as well as yielding load. Three typical failure modes of TOB connected T-stubs were observed, which were the Flange Yielding (FY), the Bolt Failure (BF) and the Coupling Failure mode (CF). The influence of the flange thickness tb and the temperature θ on the tensile behavior of the T-stub were discussed. The initial stiffness and the yielding load decreased with the increase of the temperature. The T-stubs almost lost their resistance when the temperature exceeded 700℃. The failure modes of T-stubs were mainly decided by the flange thickness, which relates to the anchorage of the hole threads and the bending resistance of flange. The failure mode could also be changed by the high temperature. Design equations in EN 1993-1-8 were modified and verified by the FEM results. The results showed that these equations could predict the failure mode and the yielding load at different temperatures with satisfactory accuracy.

• 재무관리연구
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• 제26권3호
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• pp.139-169
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• 2009

본 연구는 새로운 VaR 추정모형으로 수정 VaR(modified VaR)을 소개하고, 수정 VaR의 예측성과를 역사적 시뮬레이션 모형이나 Riskmetrics 등 전통적인 모형들과 비교하였다. 수정 VaR은 분산뿐만 아니라 왜도, 첨도를 VaR 계산에 고려함으로써 금융자산분포의 비대칭성과 꼬리가 굵은 성질이 위험측정치에 반영될 수 있는 장점이 있다. 수정 VaR은 6개국의 주가지수 수익률을 이용한 표본외 예측성과검증에서 다른 모형들에 비해 가장 우수한 예측성과를 보였다. VaR 예측의 독립성검증에서는 Riskmetrics와 GARCH 모형이 우수한 것으로 나타났으나 수정 VaR에 대해 서도 독립성이 기각되지 않았다. 특정한 표본을 이용한 예측성과분석에서 나타날 수 있는 data snooping 문제를 해결하기 위해 skew t 분포를 이용한 시뮬레이션분석을 시도하였는데, 시뮬레이션 검증결과에서도 수정 VaR이 가장 양호한 예측성과를 보였다. 포트폴리오 VaR에 대한 표본외 예측성과에서도 수정 VaR은 단일변량모형이나 다변량 정규분포모형에 비해 우수한 성과를 보였다. 다변량 수정 VaR은 포트폴리오 구성자산 간의 선형상관관계뿐 아니라 공왜도(coskewness)와 공첨도(cokurtosis)를 통한 비선형 상호의존관계도 고려할 수 있다는 점에서 포트폴리오 위험에 대한 우수한 예측성과는 당연한 결과라고 할 수 있다. 6개국 주가지수로 구성된 포트폴리오의 VaR을 component VaR로 분할한 실증분석에서는 포트폴리오 VaR의 분할결과가 적극적인 위험관리와 포트폴리오 최적화를 위한 자산재배분에 효과적으로 활용될 수 있음을 확인하였다.

• 아동학회지
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• 제9권2호
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• pp.29-59
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• 1988

Empathy was defined in this study as the vicarious affective response of a person to the perceived experience of another. The purpose of this study was to study the relationship between empathic development of children and intimacy with parents, socio-economic status, and children's empathic response to specific affective situations happy, sad, angry and fearful. The subjects for this study were 8-, 10-, and 12-year-old children attending an elementary school located in Seoul. Among the subjects, 158 boys and 149 girls lived with their parents, and 20 boys and 35 girls were reared in orphanges. They were from a residential area with higher, middle, and lower class families. The instruments consisted of two modified empathy measures and two questionnaires developed by the researcher. One of the empathy measures was based on Feshbach & Roe's affective situation test for empathy. In order to determine the eight themes, 20 children were interviewed individually about situations that made them "happy, sad, angry, and afraid". From the pool of responses, eight themes representing happy, sad, angry and fearful situations were selected. Each story consisted of a series of three pictures accompanying narration. Another modified empathy measure was developed by the researcher based upon Bryant's empathy scale. This measure consisted of 17 statements describing happy, sad, angry and fearful situations. The items in this scale were selected from a pilot study. The two questionnaires developed by the researcher were to test children's intimacy for their parents and feminity. The data was analyzed with T-test and F-test. Children's intimacy with their parents, particularly, son's intimacy with their mothers, was a significant variable in empathic development. Children living with their parents had higher scores on Feshbach & Roe's Empathy Test than those brought up in orphanages. In general, the older the children the higher the empathy score. Girls were more empathic than boys on Bryant's scale. The subjects showed their highest empathy score in the sad, and the lowest in the fearful situation. The older the children the higher the empathy score in the sad and angry situations. These results reflected children's life experiences and cultural differences. Particularly, mother-son intimacy found in this study contrasts with the mother-daughter intimacy found in American studies.

• 유공압시스템학회논문집
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• 제4권3호
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• pp.13-21
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• 2007

A forklift is a motive machine powered by LPG, diesel engine or electric motors. The internal combustion engine type forklift is equipped with automatic transmission to meet the required drive load as well as the easy operation of the vehicle. This paper deals with the shift control and endurance test controller which is developed for the functional test of the newly designed automatic transmission on a dynamometer test bench. Its major function is to control the proportional solenoid currents, which is directly related to clutch pressures, for the given reference current trajectory during shift and sequential operation of shift schedule designed for the durability test at each gear. It also has the ability to monitor all the necessary test data through RS232 communication and log them to disk files. The current controller of embedded system is designed from the identified dynamics of solenoid coil and the current reference can be easily modified with a user interface software on PC so as to match the shift data by experiments.

• Journal of Periodontal and Implant Science
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• 제36권1호
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• pp.211-221
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• 2006

The aim of present study was to evaluate the influence of periodontal status of adjacent tooth and loading time to the prevalence of red complex of implant sulcus. In 97 patients, partially edentulous subjects with endosseous root-form implants were selected. All subjects were medically healthy and had not taken systemic antibiotics and professional plaque control 3 months before sampling. The number was as follows: clinically healthy implants:161, clinically unhealthy implants:22, clinically healthy adjacent teeth:73, clinically unhealthy adjacent teeth:38. All teeth and implants of each patient were examined probing depth(PD), modified sulcus bleeding index(mSBI), and modified plaque index(mPI), and samples of subgingival plaque were obtained at each site with sterile curet or fine paper points, then the plaque transferred to PBS. Obtained samples were examined for the presence of P. gingivalis, T. forsythensis, and T. denticola by the polymerase chain reaction (PCR). The relationship among clinical parameters and the colonizations by the 3 bacterial species from adjacent teeth and implants region were analyzed by student t-test (p<0.05). The results of this study were as follows: 1. mPI and mSBI of implant increased with increasing of same indices of adjacent tooth(p=0.03,0.001), but not in the PD . 2. The mPI, mBI, PD of implants was higher when red complex exist. 3. The prevalence of red complex was higher when the periodontal condition is unhealthy. 4. The prevalence of red complex of implants has no significant relation to the probing depth of adjacent tooth. 5. Prevalence of P. gingivalis, T. forsythensis of implants increased with loading time. (p=0.02,0.018) These results shows the importance of oral hygiene and supportive periodontal therapy.

• 자원리싸이클링
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• 제7권2호
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• pp.53-58
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• 1998

본 연구는 폐타이어 고무분말을 이용한 아스팔트 콘크리트 혼합물의 성질에 대한 실험적 연구결과를 나타내고 있다. 기존의 재래식 아스팔트 혼합물과 폐타이어 고무분말 첨가 아스팔트 혼합물의 성상을 비교하기 위하여 다양한 물성 시험을 실시하였다. 고온에서 아스팔트 혼합물의 소성변형에 대한 저항성 평가인 휠트랙킹 시험결과 고무분말을 함유한 아스팔트 혼합물이 기존의 재래식 아스팔트 혼합물보다 약 50% 정도 상회하는 결과를 보였다. 또한, 표층용 아스팔트 혼합물을 유사한 기상조건과 하중을 가하여 아스팔트 혼합물의 내구성을 측정하는 라벨링 시험을 실시하였다. 시험결과 고무분말을 함유한 아스팔트 공시체가 재래식에 비하여 약 15%정도 우수하였다. 따라서, 향후 폐타이어의 적극적인 도로용 재료로서의 활용은 공학적인 측면에서 뿐만 아니라 폐자원의 리싸이클링 측면에서 고려될 때 향후 커다란 이득이 될 수 있을 것으로 예상된다.

• 한국의상디자인학회지
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• 제16권4호
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• pp.177-188
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• 2014

This research is aimed at analyzing the evaluation for the design and satisfaction/unsatisfaction of the autumn and winter school uniform targeting junior students and sophomore students at academical and vocational high schools located in Ulsan, Korea. For this research, SPSS 12.0 was used to measure the frequency and the t-test analysis of 396 data. The results of this study are as follows. The most important factor of autumn-winter school uniforms was heat-retainment. It was showed significant differences between sphere and grade. They also answered body shape' faults and figure emphasis as the most distressed factors. In the design of the school uniform, It was not show significant differences between sphere and grade. They considered the silhouette when they worn the school uniform as the most important factor. The primary factors in purchasing a uniform appeared to be price. Repair experiences after purchasing a school uniform found to count more among students. Examination about transformed parts of uniforms for the students with experiences in uniform modification showed that many students in the academic sphere modified length and width of upper wears, and length of skirt, while many students in the vocational sphere modified waist and hip. Junior grade than sophomore grade appeared to have modified in all parts.

• PNF and Movement
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• 제21권3호
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• pp.319-326
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• 2023

Purpose: The purpose of this study was to investigate the effects of modified ankle movement patterns on participants' active dorsiflexion range of motion and leg muscle activity. Methods: This study recruited twenty-five participants, all of whom were healthy individuals with no abnormalities in the ankle or knee joints. The research methodology involved measuring the active dorsiflexion range of motion and muscle activity in each person's legs based on the presence or absence of toe extension while the subjects were in a comfortable, supine position. A statistical analysis was conducted using SPSS 25.0, and a paired samples t-test was employed. The significance level was set at 0.05. Results: When the participants demonstrated the modified ankle movement pattern with a controlled toe grip, there was an increase in their active dorsiflexion angle. However, during the proprioceptive neuromuscular facilitation technique without a controlled toe grip, a higher level of activity was observed in the leg muscles. Conclusion: The results of this study could be used as foundational data for establishing a rehabilitation exercise program designed to enhance range of motion and muscle activation in the ankle joint.