• International Journal of Automotive Technology
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• v.2 no.1
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• pp.17-23
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• 2001

Measurements of the initial values lead to an inverse and mathematically unprecisely formulated problem. A precise definition of an inverse problem is possible. It is to state a mathematical model of a physical process with clearly defined initial and exit values for the system behind the process. One can grasp the idea of an inverse problem by considering the tire as a copy of the objects of nature in a room with observations. Interpretation of nature is generally a result of an inverse problem. On one hand, the tire may be represented through the sensory organs and the nervous system as well as the experiences of the developer's existing apparatus of the projection of reality. On the other hand, it may be represented by a physical law or a model that can be confirmed or is to be refuted with the help of suitable measurements. During reconstruction of a measuring signal and the identification of a black box that can be assumed to be linear and causal, the tire becomes a first type Volterra integral equation of the convolution type. But measurements of the initial values are always fuzzy, the errors grow and the system behavior can no longer be forecasted. Thus, we have to deal with a chaotic system. This chaos produces fractals in a natural way. These are self-similar geometric structures. This self-similarity is clearly visible in the design.

• The Journal of Korean Physical Therapy
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• v.28 no.6
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• pp.393-397
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• 2016

Purpose: This study was conducted in an effort to determine the effects of various abdominal drawing-in maneuver (ADIM) on the thickness and length of the transversus abdominis (TrA) when using lumbar stabilization exercises on healthy adults. Methods: 72 healthy adults were divided into four groups of 18 subjects each, to which different ADIM methods were applied. 1) a simple ADIM exercise, 2) an ADIM with pressure bio-feedback units, 3) an ADIM exercise with sling, and 4) an ADIM exercise with sling and vibration. Changes in the thickness and sliding length of TrA were measured when ADIM was conducted in the supine position prior to exercise and again when beginning the exercises. Following exercise, changes in the thickness and sliding length of TrA were measured using the same methods. Differences in group measurements prior to and following exercise were compared using a one-way analysis of variance. A paired t-test was applied to compare the before and after differences within each group. Results: Differences in TrA thickness change revealed that the ADIM exercise with sling and vibration group showed a significant difference in measurements taken prior to and following exercise. Differences in TrA length change revealed that the ADIM exercise with sling and vibration group showed a significant difference in measurements taken prior to and following exercise. Conclusion: ADIM exercise with vibration stimulation conducted in the bridge posture while in a prone position using a sling can be recommended as an effective exercise to improve the function of lumbar TrA.

• Journal of Fashion Business
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• v.19 no.2
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• pp.1-22
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• 2015

This study provides the basic data for clothing construction of teen girls by researching and analyzing the characteristics of physical changes of tween generation school girls between 8 to 14 age. Fifty eight items of direct measurements and 61 calculated-items based on the 6th Korean National Physical Standard Reports were used. Results were obtained by using ANOVA, SNK test, coefficient of variation and growth rate of age groups. Significant differences were found among all the age groups, and were in the increasing order of height > length > width > depth > circumference. The growth rate was found in the increasing order of bust depth > hip width > N.P. to B.P. > hip circumference > bust circumference and thigh circumference. There were dramatic increases in height, circumference and width during the age of 8~9 and 10~11, in length during age of 10~11, and in depth during age of 8~11. The growth of the vertical measurement items is slowing at the age of 13. The individual differences were great in the vertical measurements at the age of 8 and 9 and in the horizontal measurements, at the age of 10. The increasing growth of bust and hip than waist gave it a curved shape.

• Imaging Science in Dentistry
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• v.46 no.2
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• pp.93-101
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• 2016

Purpose: The objective of this study was to investigate the effect of varying resolutions of cone-beam computed tomography images on the accuracy of linear measurements of edentulous areas in human cadaver heads. Intact cadaver heads were used to simulate a clinical situation. Materials and Methods: Fiduciary markers were placed in the edentulous areas of 4 intact embalmed cadaver heads. The heads were scanned with two different CBCT units using a large field of view ($13cm{\times}16cm$) and small field of view ($5cm{\times}8cm$) at varying voxel sizes (0.3 mm, 0.2 mm, and 0.16 mm). The ground truth was established with digital caliper measurements. The imaging measurements were then compared with caliper measurements to determine accuracy. Results: The Wilcoxon signed rank test revealed no statistically significant difference between the medians of the physical measurements obtained with calipers and the medians of the CBCT measurements. A comparison of accuracy among the different imaging protocols revealed no significant differences as determined by the Friedman test. The intraclass correlation coefficient was 0.961, indicating excellent reproducibility. Inter-observer variability was determined graphically with a Bland-Altman plot and by calculating the intraclass correlation coefficient. The Bland-Altman plot indicated very good reproducibility for smaller measurements but larger discrepancies with larger measurements. Conclusion: The CBCT-based linear measurements in the edentulous sites using different voxel sizes and FOVs are accurate compared with the direct caliper measurements of these sites. Higher resolution CBCT images with smaller voxel size did not result in greater accuracy of the linear measurements.

• Journal of Korean Physical Therapy Science
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• v.2 no.1
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• pp.383-392
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• 1995

The purpose of this investigation was to determine the intratester reliability of measurements obtained with 3 Dimensional Motion Analysis System(3DMAS) by tester on normal subject. Twenty subjects between the ages of 9 and 29(x=22) were evaluated with 3DMAS using a test-retest reliability procedure after a familiarization session. Computerized 3DMAS was done with 4 50 - Hz CCD cameras connected to the ELITE system(B. T. S., Italy) and kinetic data were collected from the AMTI force platform(AMTI., U. S. A). Data were analyzed by the Eliclinic software to obtain gait parameters, joint angles and joint internal moment and power. Test-retest revealed intraclass correlation coefficients from .80 to .99. A series of paired t-tests revealed no significant differences between test and retest values. Finally, it was concluded that tester with 3DMAS could obtain reliable measurements with 3DMAS for determining kinetic, kinematic and gait parameters in normal subjects.

• Journal of the Korean Home Economics Association
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• v.38 no.3
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• pp.59-70
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• 2000

To compare physique classification by body consciousness and anthropometric index, 83 students were chosen from May to June 1998. Anthropometry including weight and height were measured and food frequency was examined by questionnaires. The results are as follows; 1) Average age of the subjects is 20.7, height 160.8cm and weight 51.4 kg. 2) All anthropometric indices and body fat percentage are highly correlated and all anthropometric indices show high and positive correlation with weight, but negative correlation with height. 3) The 55.4-75.9% of subjects were normal range by criteria of BMI and RI respectively, but the 40% of subjects were obese range by the self-consciousness of leanness/obesity. 4) The lean group was thinner in trunk and extremities, taller and lighter than the obese group. 5) When we investigated the groups classified by the body consciousness, the significant differences were found in the physical measurements related with feeling about self-obesity.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.443-448
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• 2005

This study aimed to evaluate the room acoustical performances of multi-purpose halls, analyzing the architectural features by survey and the acoustical characteristics by measurements. Moreover, vocabularies appropriate for the evaluation of the room acoustical performance were determined through questionnaire and subjective responses. From the correlation analysis and factor analysis to the physical values through measurements and the subjective evaluation using vocabularies, useful vocabularies for the evaluation of multi-purpose halls' acoustical performances were determined and physical parameters corresponding to the vocabulary were identified.

• Physical Therapy Korea
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• v.21 no.1
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• pp.47-54
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• 2014

The aim of this study was to compare the duration of hamstring flexibility improvement after 3 stretching interventions in people with limited hamstring flexibility. Twenty-two subjects (12 men, 10 women) with limited hamstring flexibility of the dominant leg received 3 stretching interventions- modified dynamic stretching (MDS), hold-relax (HR), and static stretching (SS)-in a random order. All the subjects received all 3 interventions at intervals of at least 24 hours to minimize any carry-over effect. Modified dynamic stretching was applied as a closed kinetic chain exercise in the supine position by using the sling suspension system (Redcord Trainer(R)). The SS and HR interventions were individually performed in the straight leg raising (SLR) position, and all 3 interventions were performed for 3 minutes. Outcome measures included passive knee extension (PKE) measurements. Five post-test measurements were recorded for all subjects at 3, 6, 9, 15, and 30 minutes after the interventions. MDS was associated with a significant increase in knee extension range of motion even at 30 minutes post-treatment. In contrast, the HR and SS stretching methods showed increased hamstring flexibility for only 6 minutes post-treatment. Improvements in the range of motion of knee extension (indicating enhancement in hamstring flexibility) with MDS were maintained longer than those with the HR and SS interventions. Therefore, MDS may be more effective than the other interventions for maintaining hamstring flexibility.

• Physical Therapy Rehabilitation Science
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• v.8 no.4
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• pp.194-201
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• 2019

Objective: This study aimed to investigate the reliability and validity of muscle thickness (MT) and pennation angle (PA) measurements of the ankle muscle, including the tibialis anterior (TA) and the medial gastrocnemius (MGCM), using a hands-free fixed probe and to compare it with the conventional linear probe. Design: Observational inter-rater reliability study. Methods: Thirty-three healthy subjects (20 male, 13 female) were included. In all subjects, ultrasound images were acquired from the TA and MGCM using a hands-free fixed probe and a conventional linear probe in random sequence by two examiners at two time-points within a 7-day interval. MT and PA were calculated on the taken images. Intra-class correlation coefficients (ICC), 95% confidence intervals, standard error of measurement and the Pearson's correlation coefficient were used to estimate reliability and validity. And also, Bland-Altman plots were generated for a visual representation of MT and PA at the TA and MGCM. Results: The ICC for all intra-rater reliability was 0.943 to 0.995 and that for all inter-rater reliability was 0.928 to 0.993, indicating excellent reliability. A significantly high correlation was observed between MT and PA at the TA and MGCM with use of the hands-free fixed probe and the conventional linear probe (r>0.938; p<0.001). Conclusions: The hands-free fixed probe provided excellent images for measurement of the MT and PA of the TA and MGCM and is a useful device for making clinical measurements of muscle structure without grasping of the probe.

• The Journal of Korean Physical Therapy
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• v.23 no.4
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• pp.45-51
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• 2011

Purpose: To determine the correct measurement methods of the ankle joint complex range of motion for measuring the neutral position and evaluate the rater reliability. In addition, the impact of training on the rater reliability was also assessed. Methods: The subjects were eleven healthy women, who were evaluated by two physical therapists and one physical therapist recorded the results of the study. Standard goniometer was used as the measurement tool. The ankle and subtalar joint neutral position and the active range of motion of the ankle and subtalar joint were measured. Intra-rater reliability and inter-rater reliability measures were analyzed with intraclass correlation coefficients. Results: Intra-rater reliability and inter-rater reliability ranged from high to medium for the neutral position of the ankle joint complex. Intra-rater reliability for dorsiflexion and plantarflexion measurements was medium, while the inter-rater reliability was high. The range of motion of the subtalar joint was measured, and the intra-rater reliability and inter-rater reliability were low and medium, respectively Also, the intra-rater reliability was increased with formal training of the measurement techniques. Intra-rater reliability was reduced in case the raters had not undertaken the training. Conclusion: In summary, the results obtained with the measurement tools and joint measurement of position, indicate the consistency of repeated measurements made by the same observers. Under the same circumstances along with repetition of the same measurement technique during training caused an increase in the rater reliability of formally trained raters.