• Title/Summary/Keyword: Variance Ratios

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Effect of Shoulder Position on Scapular Muscle Activity during Scapular Protraction

  • Yun, Sung Joon;Kim, Moon-Hwan;Weon, Jong-Hyuck
    • The Journal of Korean Physical Therapy
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    • v.32 no.3
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    • pp.157-162
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    • 2020
  • Purpose: This study was to evaluate several tasks performed at a high intensity in terms of their ability to elicit EMG activity in the serratus anterior by comparing the EMG activities of the serratus anterior, upper trapezius, and lower trapezius muscles during six tasks combined shoulder flexion with rotation. Methods: Fifteen healthy males were recruited to this study. Each subject was instructed to assume a sitting position without back support and asked to flex (90° or 120°) the right shoulder and protract the scapula in the sagittal plane with maximal external rotation; to assume a neutral position; or to internally rotate the glenohumeral joint. The EMG data were collected from the serratus anterior (SA), upper trapezius (UT), and lower trapezius (LT) muscles were normalized to maximum voluntary isometric contraction. The UT/LT and UT/SA muscle activity ratios in each task were assessed by calculating the surface EMG. Data were analyzed by two-way repeated-measures analysis of variance, with the level of significance set at p<0.05. Results: The results of this study, shoulder flexion with external rotation resulted in low upper trapezius/serratus anterior and upper trapezius/lower trapezius ratios and a relatively high level of serratus anterior activation. Conclusion: Shoulder flexion with external rotation used herein may be considered as important for clinical interventions aimed at selectively increasing SA strengthen and clinical selection of exercises for improving glenohumeral joint and scapulothoracic control.

A three-dimensional photogrammetric analysis of the facial esthetics of the Miss Korea pageant contestants

  • Jang, Kab Soo;Bayome, Mohamed;Park, Jae Hyun;Park, Ki-Ho;Moon, Hong-Beom;Kook, Yoon-Ah
    • The korean journal of orthodontics
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    • v.47 no.2
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    • pp.87-99
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    • 2017
  • Objective: The aims of this study were to measure and compare the facial dimensions of the Miss Korea pageant contestants and a selected group of women from the general population by using three-dimensional (3D) image analysis, as well as to compare various facial ratios to the golden ratio within each group. Methods: Three-dimensional images of 52 Miss Korea pageant contestants (MK group) and 41 young female adults selected from the general population (GP group) were acquired. Fifty-four variables and ratios were measured and calculated. Intergroup comparisons were performed using multivariate analysis of variance. Results: Compared to the GP group, the MK group showed greater total facial height and eye width, lesser lower-facial height, and lesser facial, lower-facial, and nasal widths. Moreover, compared to the GP group, the MK group had more protruded noses with greater nasolabial angle, greater vertical curvature of the foreheads, lesser horizontal curvature of the cheek, and lesser lower-lip-and-chin volume. Conclusions: The MK group had longer faces but smaller lower lips and chins than did the GP group. The golden ratio was not matching the current facial esthetic standards. These data might be beneficial for treatment planning of patients undergoing orthognathic and plastic surgeries.

An Analysis on Characteristics and Behaviors of Person with High Sugar-Intake Ratio for Reduction of Sugar Intake (당류 섭취 감소를 위한 고당류 섭취율자의 특성 및 행태 분석)

  • Han, Byeol;Kim, Ji-Young;Yang, Sung-Bum
    • The Korean Journal of Food And Nutrition
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    • v.31 no.4
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    • pp.565-570
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    • 2018
  • The objective of this study is to analyze the characteristics of persons with a high sugar-intake ratio (%E) and factors affecting sugar-intake ratio with the Korea National Health and Nutrition Examination Survey ($6^{th}$ KNHANES). The sugar-intake ratio is the calories of sugar from processed food divided by the daily total intake of calories. In this research we used two statistical methods, the cluster analysis and one-way analysis of variance (ANOVA). Cluster analysis was used to classify groups of sugar-intake ratios. For analysis of factors affecting the sugar-intake ratio, we applied the ANOVA. Korean have about a 3.89% sugar-intake ratio from processed food per day. The demographic characteristics of people with higher sugar-intake ratios were found to be more women than men, younger men with less education, more people in the household, smaller height, weight waistline and body mass index (BMI). Also office worker, lower drinking frequency, not getting a hypertension, diabetes, hyperlipidemia, lower breakfast and dinnner frequency, not experiencing nutritional education, and not using nutritional labeling. For reducing intake sugar in what are called health-hazardable nutrients in the food sanitation act, it is necessary to educate the people with high sugar ratio who were identified in this study.

Evaluation of the facial dimensions of young adult women with a preferred facial appearance

  • Kim, Sae Yong;Bayome, Mohamed;Park, Jae Hyun;Kook, Yoon-Ah;Kang, Ju Hee;Kim, Kang Hyuk;Moon, Hong-Beom
    • The korean journal of orthodontics
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    • v.45 no.5
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    • pp.253-260
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    • 2015
  • Objective: The aim of this study was to evaluate the facial dimensions of young adult women with a preferred facial appearance and compare the results with those from the general population. Methods: Twenty-five linear, nine angular, and three area measurements were made and four ratios were calculated using a sample of standardized frontal and lateral photographs of 46 young adult women with a preferred facial appearance (Miss Korea group) and 44 young adult women from the general population (control group). Differences between the two groups were analyzed using multivariate analysis of variance (MANOVA). Results: Compared with the control group, the Miss Korea group exhibited a significantly greater facial height, total facial height (TFH; trichion-menton), facial width (tragus right-tragus left), facial depth (tragus-true vertical line), and trichion-nasion/TFH ratio and smaller subnasale-menton/TFH and facial width/TFH ratios. Furthermore, the control group had smaller intercanthal and interpupillary widths. Conclusions: The Miss Korea group exhibited longer, wider, and deeper faces compared with those from the general population. Furthermore, the Miss Korea group had larger eyes, longer but less protruded noses, longer and more retruded lower lips and chins, larger lip vermilion areas, and smaller labiomental angles. These results suggest that the latest trends in facial esthetics should be considered during diagnosis and treatment planning for young women with dentofacial abnormalities.

Feature Vector Decision Method of Various Fault Signals for Neural-network-based Fault Diagnosis System (신경회로망 기반 고장 진단 시스템을 위한 고장 신호별 특징 벡터 결정 방법)

  • Han, Hyung-Seob;Cho, Sang-Jin;Chong, Ui-Pil
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.20 no.11
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    • pp.1009-1017
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    • 2010
  • As rotating machines play an important role in industrial applications such as aeronautical, naval and automotive industries, many researchers have developed various condition monitoring system and fault diagnosis system by applying various techniques such as signal processing and pattern recognition. Recently, fault diagnosis systems using artificial neural network have been proposed. For effective fault diagnosis, this paper used MLP(multi-layer perceptron) network which is widely used in pattern classification. Since using obtained signals without preprocessing as inputs of neural network can decrease performance of fault classification, it is very important to extract significant features of captured signals and to apply suitable features into diagnosis system according to the kinds of obtained signals. Therefore, this paper proposes the decision method of the proper feature vectors about each fault signal for neural-network-based fault diagnosis system. We applied LPC coefficients, maximum magnitudes of each spectral section in FFT and RMS(root mean square) and variance of wavelet coefficients as feature vectors and selected appropriate feature vectors as comparing error ratios of fault diagnosis for sound, vibration and current fault signals. From experiment results, LPC coefficients and maximum magnitudes of each spectral section showed 100 % diagnosis ratios for each fault and the method using wavelet coefficients had noise-robust characteristic.

Physico-Mechanical Properties of Cement-Bonded Boards Produced from Mixture of Corn Cob Particles and Gmelina arborea Sawdust

  • Adelusi, Emmanuel Adekanye;Olaoye, Kayode Oladayo;Adelusi, Felicia Temitope;Adedokun, Samuel Ayotunde
    • Journal of Forest and Environmental Science
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    • v.37 no.1
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    • pp.79-89
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    • 2021
  • Cement bonded boards of 10 mm in thickness were produced from the mixture of Gmelina arborea sawdust and corn cob particles. The strength and dimensional stability of cement bonded composites produced from these two mixtures were examined. A total of thirty experimental boards were produced at density level of 1,000 kg/㎥ with cement to fibre ratio of 2.5:1 and 3:1 and five (5) blending proportions of G. arborea sawdust to corn cob particles of 100:0; 75:25; 50:50; 25:75 and 100:0. The effect of the cement to fibre ratio and blending proportion on the Water Absorption (WA), Thickness Swelling (TS), Modulus of Rupture (MOR), and Modulus of Elasticity (MOE) were determined. The result indicates that as the mixing ratio of cement to fibre and blending proportion of maize cob (75%) to G. arborea (25%) increased, the thickness swelling, water absorption decreased, whereas the MOR and MOE increased. It also shows that most dimensionally stable and flexural strength boards were produced at the highest level of mixing ratios (3:1) and blending proportion of G. arborea to corn cob 25:75. However, the analysis of variance shows that TS and WA were significantly different, whereas, MOE and MOR were not significantly affected by mixing ratios and blending proportions. Finding of this study has shown that maize cob particles are suitable for cement bonded board production.

The Application of Thera-band on Non-weight Bearing Leg Influence Hip Abductor Activities During Pelvic Drop Exercise in Patients With Gluteus Medius Weakness

  • Su-hwan Cha;Seok-hyun Kim;Seung-min Baik;Heon-seock Cynn
    • Physical Therapy Korea
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    • v.30 no.1
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    • pp.68-77
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    • 2023
  • Background: The weakness of the gluteus medius (GM) is associated with various musculoskeletal disorders. The increasing GM activity without synergistic dominance should be considered when prescribing pelvic drop exercise (PD). Isometric hip extension or flexion of the non-weight bearing leg using thera-band at the ankle during PD may influence hip abductor activities. Objects: To determine how isometric hip extension or flexion of the non-weight bearing leg using thera-band at the ankle during PD influences the activities of three subdivisions of GM (anterior, GMa; middle, GMm; posterior, GMp), tensor fasciae latae (TFL), contralateral quadratus lumborum (QL), and GMp/TFL, GMm/QL activity ratios in patients with GM weakness. Methods: Twenty-three patients with GM weakness were recruited. Three types of PD were performed: PD, PD with an isometric hip extension of the non-weight bearing leg (PDE), and PD with an isometric hip flexion of the non-weight bearing leg (PDF). Surface electromyography (SEMG) was used to measure hip abductor activities. One-way repeated-measures analysis of variance was used to assess the statistical significance of muscle activities and muscle activity ratios. Results: GMa, GMm, and GMp activities were significantly greater during PDF than during PD and PDE (p < 0.001, p = 0.001; p = 0.001, p = 0.005; p = 0.004, p = 0.004; respectively). TFL activity was significantly greater during PDE than during PD and PDF (p < 0.001, p < 0.001, respectively). QL activity was significantly greater during PDF than during PD (p = 0.003). GMp/TFL activity ratio was significantly lower during PDE than during PD and PDF (p = 0.001, p = 0.001, respectively). There were no significant differences in the GMm/QL activity ratio. Conclusion: PDF may be an effective exercise to increase the activities of all three GM subdivisions while minimizing the TFL activity in patients with GM weakness.

An Unconventional Approach Considering Flexor Spasticity and Flexion Synergies of the Upper Extremity Following a Stroke: A Randomized Double-blind Pilot Study

  • Rha, Young Hyoun;Lee, Keun Hee;Shin, Jun Bum;Park, Kang Hui;Kim, Byung Sun;Ha, Jae Chan
    • Physical Therapy Korea
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    • v.29 no.2
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    • pp.147-155
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    • 2022
  • Background: Although various conventional approaches have been employed to reduce spasticity in neurological rehabilitation, only a few studies have shown scientific evidence for its effectiveness. Thus, we introduced a different concept (Ueda method) of rehabilitation therapy that can complement the limitations of conventional therapy. Objects: This study aimed to investigate the immediate effects of the application of the Ueda method on patients with spasticity after stroke via an electrophysiological study. Methods: We conducted a randomized double-blind pilot study in two rehabilitation hospitals involving 30 stroke patients who were randomly allocated to the Ueda (n = 15) and convention (n = 15) groups. Electromyographic data of six examined muscles in both upper extremities of all patients were recorded. The A-ApA index and activation ratios of upper extremity muscles were evaluated and compared between the groups to confirm post-intervention changes in upper-extremity flexor spasticity and flexion synergies. Repeated-measures analysis of variance was conducted to confirm the therapeutic effect (2 × 2) as a function of group (Ueda vs. convention) and time (pre-/post-intervention) on all outcome measures (p < 0.05). Results: In the Ueda group, the mean A-ApA index values differed significantly before and after the intervention (p = 0.041), indicating a weak evidence level; however, the effect size was medium (d = -0.503). The interaction effects of the A-ApA index between the Ueda and convention groups and between pre-intervention and post-intervention stages were significant (p = 0.012). The effect size was large (np2 = 0.220). In the Ueda group, the activation ratios of the anterior deltoid fiber significantly decreased after the intervention in all reaching tasks. Conclusion: The Ueda method reduces upper-extremity flexor spasticity and changes its synergy in stroke patients and should be considered a rehabilitation therapy for spastic stroke patients.

Measurement of Shunt Amount Using Radionuclide Angiocardiography: Accuracy According to Level of Shunt and Associated Lesion (방사성 동위원소 심혈관 조영술을 이용한 단락량 측정법: 정확성에 영향을 미치는 인자)

  • Kim, Yang-Min
    • Nuclear Medicine and Molecular Imaging
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    • v.40 no.4
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    • pp.200-204
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    • 2006
  • Purpose: Determination of pulmonary to systemic blood flow ratio (QP/QS) is important for the management of patients with left-to-right shunt. This study was performed to assess the agreement of Qp/Qs ratio using the radionuclide method and oxymetry, to investigate the factors influencing the agreement, and to know how interchangeable the results of each technique. Materials and Methods: We compared the Qp/Qs measured by single-pass radionuclide angiocardiography and oxymetry during catheterization in 207 patients who underwent both studies. In radionuclide method, Qp/Qs was calculated from the pulmonary time-activity curves using a gamma variate fit. The correlation and Bland-Altman analysis were performed according to the levels of shunt and associated lesions. Results: The mean Qp/Qs was $1.83{\pm}0.50$ by radionuclide, and $1.74{\pm}0.51$ by oxymetry. The overall correlation coefficient was 0.86(p<0.001), and Bland-Altman range of agreement encompassing 4SD was 1.05. For atrial septal defect, ventricular septal defect, patent ductus arteriosus, tricuspid and mitral insufficiency, the correlation coefficient was 0.78, 0.90, 0.84, 0.63 and 0.44, and Bland-Altman range was 1.51, 0.74, 0.96, 1.57, and 1.50, respectively. Conclusion: There is good agreement but wide variance between the Qp/Qs ratios by radionuclide method and oxymetry. Associated atrioventricular valvar insufficiency decreases the correlation coefficient and widens the variance. Wide overall variance suggests that Qp/Qs measurements by two techniques should not be used interchangeably.

The Hedging Effectiveness of Shrimp Futures Contract and Futures Contract Design (새우 선물계약의 헤징유효성과 선물계약 설계)

  • Kang, Seok-Kyu
    • The Journal of Fisheries Business Administration
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    • v.41 no.1
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    • pp.73-91
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    • 2010
  • The objective of this study is to examine the hedging effectiveness of shrimp futures market. Hedging effectiveness is measured by OLS model based on rolling windows. Analysis data are obtained from Kansai Commodities Exchange in Osaka and are weekly data of frozen shrimp futures and cash prices in the time period from July 9, 2003, to May 9, 2007. The empirical results are summarized as follows:First, the correlation coefficients between the nearby futures price changes and the cash(16/20) price changes are very low and have range from 0.141 to 0.208 values. Second, the minimum variance hedge ratios($\hat{\beta}$) are all statistically different from 0 at the 5% level and range from 0.0477 to 0.5039 values excluding Indian shrimps(26/30). Ex post hedging effectiveness, as measured by the coefficient of determination, $R^2$, is relatively very low and range from a low of 0.4% for west-south Indian shrimps(26/30) to a high 4.3% for Vietnamese shrimps(16/20). Third, ex ante hedging effectiveness, as measured by out-of-sample hedging period, is also very low and range from a low of -4.4% for west-south Indian shrimps(21/25) to a high of 3.4% for Vietnamese shrimps(16/20). This indicates that the shrimp futures market doesn't behave as risk management instrument of shrimp spot.