• 제목/요약/키워드: weight training

검색결과 1,015건 처리시간 0.022초

자세교정을 위한 체위변환 감지 센서 디바이스의 정확성 평가 (Evaluation of measuring accuracy of body position sensor device for posture correction)

  • 최정현;박준호;강민호;서재용;김수찬
    • 융합신호처리학회논문지
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    • 제22권3호
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    • pp.128-133
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    • 2021
  • 최근 학생 및 사무직 종사자의 자세 불량으로 인한 척추계 질환의 발병율이 증가하고 있으며, 바른 자세 유지를 돕기 위한 다양한 연구가 수행되었다. 기존 연구에서는 의자 방석부분에 멤브레인 센서 또는 압력센서를 배치하여 무게의 편중을 보거나, 사용자를 구속하는 센서를 부착하여 체위변환을 측정하였다. 본 연구자는 선행연구에서 점착성 겔시트로 간편히 몸에 부착할 수 있으며, 사용자의 자세 및 체위 변화를 실시간으로 측정하여 출력하는 센서 디바이스를 개발하였으나 센서값의 정확성에서 한계점을 보였다. 본 연구에서는 체위변환 센서 디바이스의 성능을 개선하고, 각도변환 측정값의 정확도를 정량적으로 평가하는 연구를 수행하였으며, 오차율 2.53%의 높은 정확도를 확인하였다. 향후 연구에서는 멀티미디어 요소가 추가된 자세교정 훈련 컨텐츠를 보다 다양화하여 실제 사용자를 대상으로 하는 추가 연구가 필요한 것으로 사료된다.

Effect on the Center of Pressure of Vision, Floor Condition, and the Height of Center of Mass During Quiet Standing

  • Kim, Seung-su;Lim, Kitaek;Choi, Woochol Joseph
    • 한국전문물리치료학회지
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    • 제28권2호
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    • pp.154-160
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    • 2021
  • Background: Theoretically, balance is affected by the height of center of mass (COM) during quiet standing. However, no one examined this in humans with variables derived from the center of pressure (COP). Objects: We have conducted balance experiment to measure COP data during quiet standing, in order to examine how the COP measures were affected by the height of COM, vision, floor conditions, and gender. Methods: Twenty individuals stood still with feet together and arms at sides for 30 seconds on a force plate. Trials were acquired with three COM heights: 1% increased or decreased, and not changed, with two vision conditions: eyes closed (EC) and eyes open (EO), and with two floor conditions: unstable (foam pad) and stable (force plate) floor. Outcome variables included the mean distance, root mean square distance, total excursion, mean velocity, and 95% confidence circle area. Results: All outcome variables were associated with the COM height (p < 0.0005), vision (p < 0.0005), and floor condition (p < 0.003). The mean velocity and 95% confidence circle area were 5.7% and 21.8% greater, respectively, in raised COM than in lowered COM (24.6 versus 23.2 mm/s; 1,013.4 versus 832.3 mm2). However, there were no interactions between the COM height and vision condition (p > 0.096), and between the COM height and floor condition (p > 0.183) for all outcome variables. Furthermore, there was no gender difference in all outcome variables (p > 0.186). Conclusion: Balance was affected by the change of COM height induced by a weight belt in human. However, the effect was not affected by vision or floor condition. Our results should inform the design of balance exercise program to improve the outcome of the balance training.

Evaluating flexural strength of concrete with steel fibre by using machine learning techniques

  • Sharma, Nitisha;Thakur, Mohindra S.;Upadhya, Ankita;Sihag, Parveen
    • Composite Materials and Engineering
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    • 제3권3호
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    • pp.201-220
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    • 2021
  • In this study, potential of three machine learning techniques i.e., M5P, Support vector machines and Gaussian processes were evaluated to find the best algorithm for the prediction of flexural strength of concrete mix with steel fibre. The study comprises the comparison of results obtained from above-said techniques for given dataset. The dataset consists of 124 observations from past research studies and this dataset is randomly divided into two subsets namely training and testing datasets with (70-30)% proportion by weight. Cement, fine aggregates, coarse aggregates, water, super plasticizer/ high-range water reducer, steel fibre, fibre length and curing days were taken as input parameters whereas flexural strength of the concrete mix was taken as the output parameter. Performance of the techniques was checked by statistic evaluation parameters. Results show that the Gaussian process technique works better than other techniques with its minimum error bandwidth. Statistical analysis shows that the Gaussian process predicts better results with higher coefficient of correlation value (0.9138) and minimum mean absolute error (1.2954) and Root mean square error value (1.9672). Sensitivity analysis proves that steel fibre is the significant parameter among other parameters to predict the flexural strength of concrete mix. According to the shape of the fibre, the mixed type performs better for this data than the hooked shape of the steel fibre, which has a higher CC of 0.9649, which shows that the shape of fibers do effect the flexural strength of the concrete. However, the intricacy of the mixed fibres needs further investigations. For future mixes, the most favorable range for the increase in flexural strength of concrete mix found to be (1-3)%.

변증(辨證) 기반 진료수행시험(CPX) 시나리오를 이용한 역할극에 대한 학생 자가 평가의 일치도와 개선 방안 (Consistency of Student Self-Assessment of Role Play Using the Syndrome Differentiation-Based Clinical Performance Examination Scenario and Improvement Measures)

  • 조학준;조나영;박정수
    • 대한예방한의학회지
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    • 제26권2호
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    • pp.37-53
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    • 2022
  • Objectives : This study analyzed the concordance between student self-assessment and peer-evaluation in a role play using the Clinical Performance Examination (CPX) scenario developed based on Korean medical syndrome differentiation. Methods : The subjects of this study are first-year-students majoring in Korean Medicine. The role play based on clinical case was performed in the class of Korean Medicine Classics. Feedback on clinical skill competency got through student self-assessment and peer-evaluation, and this study was compared and analyzed of result. Results : A simple comparison of the results of self-assessment and peer-evaluation in the evaluation results of clinical skill competency may appear to be consistent. However, it was not statistically significant. It is necessary to enhance the discriminative ability in the evaluation of clinical skill competency. It will be possible to improve a bit by relatively increasing the weight of the scores on the items that students expect to respond differently among the evaluation items. In addition, in order to dramatically improve the systemicity and reliability of the evaluation of clinical skill competency itself, it is necessary to introduce the Introduction to Clinical Traditional Korean Medicine (ICTKM) course. Conclusions : Student's self-assessment and peer-evaluation as feedback on clinical skill competency are suitable for the purpose of education and training. However, the reliability of the evaluation was not statistically significant.

Prediction of Stunting Among Under-5 Children in Rwanda Using Machine Learning Techniques

  • Similien Ndagijimana;Ignace Habimana Kabano;Emmanuel Masabo;Jean Marie Ntaganda
    • Journal of Preventive Medicine and Public Health
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    • 제56권1호
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    • pp.41-49
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    • 2023
  • Objectives: Rwanda reported a stunting rate of 33% in 2020, decreasing from 38% in 2015; however, stunting remains an issue. Globally, child deaths from malnutrition stand at 45%. The best options for the early detection and treatment of stunting should be made a community policy priority, and health services remain an issue. Hence, this research aimed to develop a model for predicting stunting in Rwandan children. Methods: The Rwanda Demographic and Health Survey 2019-2020 was used as secondary data. Stratified 10-fold cross-validation was used, and different machine learning classifiers were trained to predict stunting status. The prediction models were compared using different metrics, and the best model was chosen. Results: The best model was developed with the gradient boosting classifier algorithm, with a training accuracy of 80.49% based on the performance indicators of several models. Based on a confusion matrix, the test accuracy, sensitivity, specificity, and F1 were calculated, yielding the model's ability to classify stunting cases correctly at 79.33%, identify stunted children accurately at 72.51%, and categorize non-stunted children correctly at 94.49%, with an area under the curve of 0.89. The model found that the mother's height, television, the child's age, province, mother's education, birth weight, and childbirth size were the most important predictors of stunting status. Conclusions: Therefore, machine-learning techniques may be used in Rwanda to construct an accurate model that can detect the early stages of stunting and offer the best predictive attributes to help prevent and control stunting in under five Rwandan children.

Single-step genomic evaluation for growth traits in a Mexican Braunvieh cattle population

  • Jonathan Emanuel Valerio-Hernandez;Agustin Ruiz-Flores;Mohammad Ali Nilforooshan;Paulino Perez-Rodriguez
    • Animal Bioscience
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    • 제36권7호
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    • pp.1003-1009
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    • 2023
  • Objective: The objective was to compare (pedigree-based) best linear unbiased prediction (BLUP), genomic BLUP (GBLUP), and single-step GBLUP (ssGBLUP) methods for genomic evaluation of growth traits in a Mexican Braunvieh cattle population. Methods: Birth (BW), weaning (WW), and yearling weight (YW) data of a Mexican Braunvieh cattle population were analyzed with BLUP, GBLUP, and ssGBLUP methods. These methods are differentiated by the additive genetic relationship matrix included in the model and the animals under evaluation. The predictive ability of the model was evaluated using random partitions of the data in training and testing sets, consistently predicting about 20% of genotyped animals on all occasions. For each partition, the Pearson correlation coefficient between adjusted phenotypes for fixed effects and non-genetic random effects and the estimated breeding values (EBV) were computed. Results: The random contemporary group (CG) effect explained about 50%, 45%, and 35% of the phenotypic variance in BW, WW, and YW, respectively. For the three methods, the CG effect explained the highest proportion of the phenotypic variances (except for YW-GBLUP). The heritability estimate obtained with GBLUP was the lowest for BW, while the highest heritability was obtained with BLUP. For WW, the highest heritability estimate was obtained with BLUP, the estimates obtained with GBLUP and ssGBLUP were similar. For YW, the heritability estimates obtained with GBLUP and BLUP were similar, and the lowest heritability was obtained with ssGBLUP. Pearson correlation coefficients between adjusted phenotypes for non-genetic effects and EBVs were the highest for BLUP, followed by ssBLUP and GBLUP. Conclusion: The successful implementation of genetic evaluations that include genotyped and non-genotyped animals in our study indicate a promising method for use in genetic improvement programs of Braunvieh cattle. Our findings showed that simultaneous evaluation of genotyped and non-genotyped animals improved prediction accuracy for growth traits even with a limited number of genotyped animals.

Gynostemma pentaphyllum extract and its active component gypenoside L improve the exercise performance of treadmill-trained mice

  • Kim, Yoon Hee;Jung, Jae In;Jeon, Young Eun;Kim, So Mi;Hong, Su Hee;Kim, Tae Young;Kim, Eun Ji
    • Nutrition Research and Practice
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    • 제16권3호
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    • pp.298-313
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    • 2022
  • BACKGROUND/OBJECTIVES: The effectiveness of natural compounds in improving athletic ability has attracted attention in both sports and research. Gynostemma pentaphyllum (Thunb.) leaves are used to make traditional herbal medicines in Asia. The active components of G. pentaphyllum, dammarane saponins, or gypenosides, possess a range of biological activities. On the other hand, the anti-fatigue effects from G. pentaphyllum extract (GPE) and its effective compound, gypenoside L (GL), remain to be determined. MATERIALS/METHODS: This study examined the effects of GPE on fatigue and exercise performance in ICR mice. GPE was administered orally to mice for 6 weeks, with or without treadmill training. The biochemical analysis in serum, glycogen content, mRNA, and protein expressions of the liver and muscle were analyzed. RESULTS: The ExGPE (exercise with 300 mg/kg body weight/day of GPE) mice decreased the fat mass percentage significantly compared to the ExC mice, while the ExGPE showed the greatest lean mass percentage compared to the ExC group. The administration of GPE improved the exercise endurance and capacity in treadmill-trained mice, increased glucose and triglycerides, and decreased the serum creatine kinase and lactate levels after intensive exercise. The muscle glycogen levels were higher in the ExGPE group than the ExC group. GPE increased the level of mitochondrial biogenesis by enhancing the phosphorylation of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) protein and the mRNA expression of nuclear respiratory factor 1, mitochondrial DNA, peroxisome proliferator-activated receptor-δ, superoxide dismutase 2, and by decreasing the lactate dehydrogenase B level in the soleus muscle (SOL). GPE also improved PGC-1α activation in the SOL significantly through AMPK/p38 phosphorylation. CONCLUSIONS: These results showed that GPE supplementation enhances exercise performance and has anti-fatigue activity. In addition, the underlying molecular mechanism was elucidated. Therefore, GPE is a promising candidate for developing functional foods and enhancing the exercise capacity and anti-fatigue activity.

Effect of length and content of steel fibers on the flexural and impact performance of self-compacting cementitious composite panels

  • Denise-Penelope N. Kontoni;Behnaz Jahangiri;Ahmad Dalvand;Mozafar Shokri-Rad
    • Advances in concrete construction
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    • 제15권1호
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    • pp.23-39
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    • 2023
  • One of the important problems of concrete placing is the concrete compaction, which can affect the strength, durability and apparent quality of the hardened concrete. Therefore, vibrating operations might be accompanied by much noise and the need for training the involved workers, while inappropriate functioning can result in many problems. One of the most important methods to solve these problems is to utilize self-compacting cementitious composites instead of the normal concrete. Due to their benefits of these new materials, such as high tensile, compressive, and flexural strength, have drawn the researchers' attention to this type of cementitious composite more than ever. In this experimental investigation, six mixing designs were selected as a base to acquire the best mechanical properties. Moreover, forty-eight rectangular composite panels with dimensions of 300 mm × 400 mm and two thickness values of 30 mm and 50 mm were cast and tested to compare the flexural and impact energy absorption. Steel fibers with volume fractions of 0%, 0.5% and 1% and with lengths of 25 mm and 50 mm were imposed in order to prepare the required cement composites. In this research, the composite panels with two thicknesses of 30 mm and 50 mm, classified into 12 different groups, were cast and tested under three-point flexural bending and repeated drop weight impact test, respectively. Also, the examination and comparison of flexural energy absorption with impact energy absorption were one of the other aims of this research. The obtained results showed that the addition of fibers of longer length improved the mechanical properties of specimens. On the other hand, the findings of the flexural and impact test on the self-compacting composite panels indicated a stronger influence of the long-length fibers.

대학도서관 사서의 교수 불안에 대한 연구 (A Study on Teaching Anxiety of University Librarians)

  • 오선혜
    • 한국문헌정보학회지
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    • 제57권2호
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    • pp.321-347
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    • 2023
  • 본 연구의 목적은 대학도서관 교육 담당 사서가 경험하는 교수 불안(Teaching anxiety)에 대해 파악하고 이를 완화하기 위한 지원 방안을 제안하는 것이다. 연구의 목적을 달성하기 위해 전국의 A그룹 대학도서관 사서 중 교육 담당 사서를 대상으로 설문조사를 수행하였다. 총 138부의 유효한 응답 결과를 분석한 결과 전체의 84.8%에 해당하는 사서가 교수 불안을 경험한 적이 있다고 응답하였다. 교수 불안은 근무 경력, 교육업무 경력, 교육 빈도, 교육업무 비중, 교육 역할 인식 등에 대해서는 차이가 없는 것으로 나타났으나 교육 역할 진입 전 느끼는 감정과 준비도에 대해서는 유의한 차이가 있는 것으로 나타났다. 대학도서관 교육 담당 사서의 교수 불안을 완화하는 방안으로 문헌정보학 학부 과정부터 이용자 교육에 대한 교과 과정 개설과 상급 기관 또는 협의회 차원의 가이드라인 마련, 사서 전문 교육훈련 기관의 커리큘럼 다양화 등을 제안하였다.

12주간의 순환운동이 노인비만여성의 비만, 체력 및 대사증후군 지표에 미치는 영향 (The Effects of 12 Weeks of Circuit Exercise on Obesity, Physical Fitness and Metabolic Syndrome Index in Elderly Obese Women)

  • 김상훈
    • 한국노년학
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    • 제29권3호
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    • pp.823-835
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    • 2009
  • 본 연구의 목적은 12주간의 순환운동이 노인비만여성의 비만, 체력 및 대사증후군 지표에 미치는 영향을 살펴보고자 시도되었다. 65세 이상 체질량지수 25이상의 여성 자원자 총19명을 대상으로 12주간의 순환운동 프로그램을 실시하였으며, 운동 프로그램은 가벼운 유산소 운동과 스트레칭으로 준비운동을 실시 한 후 주 3회의 빈도로 매회 30분씩 12주 동안 순환운동 프로그램을 실시하였다. 12주간의 순환운동 프로그램 실시 후, 참가 전에 비해 참가 후의 체중과 체질량지수(p<.001)가 감소되었으며, 체력측정항목에서 하지근력(p<.001)과 상지 근력(p<.05), 상지 유연성(p<.05)과 하지연성(p<.05), 민첩성/동적평형성(p<.001), 전신지구력(p<.05)의 총 6개 모든 항목에서 유의한 향상이 있었고, 대사증후군 지표인 복부비만(p<.01), 수축기혈압(p<.05), 중성지방(p<.001), 고밀도 지단백(p<.01), 혈당(p<.05) 등 이완기 혈압을 제외한 모든 측정항목에서도 12주간의 순환운동 후 운동 참가 전에 비해 유의한 향상이 있었다. 결론적으로 12주간의 순환운동이 노인비만여성에 있어 체중감소와 체력향상에 긍정적인 영향을 미쳤으며, 대사증후군 지표의 개선에 효과적인 것으로 나타났다.