• Restorative Dentistry and Endodontics
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• v.38 no.1
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• pp.26-30
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• 2013

Objectives: The aim of this study was to investigate the relationship between the apical foramen morphology and the length of merged canal at the apex in type II root canal system. Materials and Methods: This study included intact extracted maxillary and mandibular human premolars (n = 20) with fully formed roots without any visible signs of external resorption. The root segments were obtained by removing the crown 1 mm beneath the cementum-enamel junction (CEJ) using a rotary diamond disk. The distance between the file tip and merged point of joining two canals was defined as Lj. The roots were carefully sectioned at 1 mm from the apex by a slow-speed water-cooled diamond saw. All cross sections were examined under the microscope at ${\times}50$ magnification and photographed to estimate the shape of the apical foramen. The longest and the shortest diameter of apical foramen was measured using ImageJ program (1.44p, National Institutes of Health). Correlation coefficient was calculated to identify the link between Lj and the apical foramen shape by Pearson's correlation. Results: The average value of Lj was 3.74 mm. The average of proportion (P), estimated by dividing the longest diameter into the shortest diameter of the apical foramen, was 3.64. This study showed a significant negative correlation between P and Lj (p < 0.05). Conclusions: As Lj gets longer, the apical foramen becomes more ovally shaped. Likewise, as it gets shorter, the apical foramen becomes more flat shaped.

• Journal of the Korea Institute of Building Construction
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• v.15 no.1
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• pp.133-141
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• 2015

The floor slipperiness is an essential property for the pedestrian safety. This study was conducted to develop the slip test apparatus to be well accorded with actual characteristics of human gait; and the correlation between RCOF (Required coefficient of friction), Rz (Surface roughness), and 3 coefficients of slip resistance (C.S.R (Coefficient of slip resistance), BPN (British pendulum number), and SCOF (Static coefficient of friction)) were analyzed. Result of the analysis revealed that the cadence, stride length, and step length were proportional to the walking speed, and the significant correlation between walking speed and RCOF was found. However, the correlation between RCOF and the other respective coefficients of slip resistance was almost unidentified thus it would be difficult to identify the actual property of floor slipperiness with the RCOF alone.

• The Journal of Korean Physical Therapy
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• v.13 no.2
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• pp.265-272
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• 2001

The object of this thesis is to study the correlation between scoliosis and foot in a theoretical and empirical method. My research process was investigated for 34 students on the forward bending test, foot printer test, feedoscope test, X-ray test and so on. The main results of this study were as follows: 1. There was statistical significance on the correlation between foot length and spine length. 2. Scoliosis angle is the smallest on the pes plannus group and the biggest on the pes cavus group without statistical significance. 3. Left lumbar curve is the smallest, and right thoracic spine curve is the biggest on the left foot pattern group with statistical significance. 4. On the foot weightbearing groups, there was statistical significance both of between left and right foot groups. 5. There was no statistical significance on the t-test analysis between left foot area and right foot area according to scoliosis typology.

• Journal of the Korean Society of Costume
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• v.52 no.2
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• pp.71-80
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• 2002

The purpose of this study was to examine the correlation between the shape of the foot and foot abrasion. and to provide preliminary data for shoe manufacturing by comparing the length of a woman's feet and the shoe size. The Martin calibrator and measuring tapes were utilized to measure the shapes of 163 female college students' feet. Indirect measurements were also obtained by line drawing of the feet for additional analysis. Brief questionnaires about what type of shoes are worn were given to the subjects of the study. Data analysis was presented by frequency, percentage, and standard deviations. Factor analysis and correlation co-efficiency of data was conducted on the significance level of p〈.05. The results of the study are as follows (1) The average number of days per week in which the subjects wear ladies' shoes per week were 4.5. Little over half of the subjects (53.87% ) answered that they wear heeled shoes for more than 8 hours per day. The most preferred height of a ladies'shoe heel was between 2 cm and 4 cm, as replied by 41.0% of the subjects. (2) The foot area where abrasion occurs most often was around the heel (51.2%) and the middle part of the sole (50.9%) (3) Factors correlated to the heel abrasion included the circumference and the breadth of the foot. The abrasion on the side of the first toe of mid-sized feet was most affected by the angle of the first the and inner foot line. The height of the foot heel was a significant factor for the abrasion near the anklebone. In conclusion, the abrasion resulted from the inappropriate fitting of the shoe and the foot. Also, the circumference and the width factors were more influential rather than the foot length. Therefore, more database on this should be systemized and available to the footwear manufacturers and the customers for more practical use of shoe size and public education.

• Plant Resources
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• v.5 no.3
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• pp.196-201
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• 2002

This study was conducted to investigate the relationships between yearly variations of climatic elements and yearly variations of productivity in sesame. In addition, correlation coefficients among yield and yield components were estimated. The data of yield and yield components were investigated for 10 years from 1992 to 2001. The meteorological data gathered at the Yeosu Weather Station for the same period were used to find out the relationships between climatic elements and productivity. Yearly variation of the amount of precipitation in July and September were large with coefficients of variation(c.v.) of 64.59, 92.47%, respectively, but the variation of the average temperature in June and August were relative small. Yield and plant height greatly with c. v. of 26.24, 23.41 %, respectively, 1, 000 grain weights show more or less c.v. of 3.83% and length capsule setting show still less variation. Correlation coefficients between maximun temperature in period of cultivation(from June to September) and yield are positively significant at the level of 5.1 %, respectively. Correlation coefficients amount the plant height, length capsule setting, number of capsules per plant, weight of 1, 000 grains and seed yield were positively significant at the level of 1 %, respectively. Simple linear regression equations by the least square method are estimated for number of capsules per plant(Y$_1$) and the maximun temperature in August(X) as $Y_1$=10.1255+0.1725X, and for yield(Y$_2$) and the maximun temperature in August(X) as $Y_2$=21.6151 + 1.3724X.

• Imaging Science in Dentistry
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• v.43 no.4
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• pp.289-293
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• 2013

Purpose: This study was performed to determine the relationship between the stage of tooth eruption (both vertical and mesio-angular) and chronological age. Materials and Methods: Indirect digital panoramic radiographs were used to measure the distances from the dentinoenamel junction (DEJ) of the second molars to the occlusal plane of the second molar teeth and of the adjacent third molars in 264 Thai males and 437 Thai females using ImageJ software. The ratio of those distances was calculated by patient age, and the correlation coefficient of the ratio of the third molar length to the second molar length was calculated. Results: The correlation between the height of the vertically erupted upper third molar teeth and age was at the intermediate level. The age range of ${\geq}15$ to <16 years was noted to be the range in which the correlation between the chronological age determined from the eruptional height and actual chronological age was statistically significant. The mean age of the female subjects, in which the position of the right upper third molar teeth was at or above the DEJ of the adjacent second molar but below one half of its coronal height was $19.9{\pm}2.6$ years. That for the left side was $20.2{\pm}2.7$ years. The mean ages of the male subjects were $20.1{\pm}3.3$ years and $19.8{\pm}2.7$ years for the right and left sides, respectively. Conclusion: It might be possible to predict chronological age from the eruption height of the wisdom teeth.

• Archives of Plastic Surgery
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• v.46 no.4
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• pp.303-310
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• 2019

Background Prosthetic hands with a myoelectric interface have recently received interest within the broader category of hand prostheses, but their high cost is a major barrier to use. Modern three-dimensional (3D) printing technology has enabled more widespread development and cost-effectiveness in the field of prostheses. The objective of the present study was to evaluate the clinical impact of a low-cost 3D-printed myoelectric-interface prosthetic hand on patients' daily life. Methods A prospective review of all upper-arm transradial amputation amputees who used 3D-printed myoelectric interface prostheses (Mark V) between January 2016 and August 2017 was conducted. The functional outcomes of prosthesis usage over a 3-month follow-up period were measured using a validated method (Orthotics Prosthetics User Survey-Upper Extremity Functional Status [OPUS-UEFS]). In addition, the correlation between the length of the amputated radius and changes in OPUS-UEFS scores was analyzed. Results Ten patients were included in the study. After use of the 3D-printed myoelectric single electromyography channel prosthesis for 3 months, the average OPUS-UEFS score significantly increased from 45.50 to 60.10. The Spearman correlation coefficient (r) of the correlation between radius length and OPUS-UEFS at the 3rd month of prosthetic use was 0.815. Conclusions This low-cost 3D-printed myoelectric-interface prosthetic hand with a single reliable myoelectrical signal shows the potential to positively impact amputees' quality of life through daily usage. The emergence of a low-cost 3D-printed myoelectric prosthesis could lead to new market trends, with such a device gaining popularity via reduced production costs and increased market demand.

• Journal of Biomedical Engineering Research
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• v.42 no.6
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• pp.295-303
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• 2021

Idiopathic normal-pressure hydrocephalus (INPH) is considered a potentially treatable neurological disorder by shunt surgery and characterized by a triad of symptoms including gait disturbance, cognitive impairment and urinary dysfunction. Although disorders of white matter are generally viewed as the principal pathological features of INPH, analysis of cortical features are important since the destruction of neural tracts could be associated with cortical structural changing. The aim of the study was to determine whether there was any relationship between gait parameter and structural features of cerebral cortex in INPH patients. Gait parameters were measured as follows: step width, toe in/out angle, coefficient of variation (CV) value of stride length, CV value of stride time. After obtaining individual brain MRI of patients with INPH and hemispheric cortical surfaces were automatically extracted from each MR volume, which reconstructed the inner and outer cortical surface. Then, cortical thickness, surface area, and volume were calculated from the cortical surface. As a result, step width was positively correlated with bilateral postcentral gyrus and left precentral gyrus, and toe in/out was positively correlated with left posterior parietal cortex and left insula. Also, the CV value of stride length showed positive correlation in the right superior frontal sulcus, left insula, and the CV value of stride time showed positive correlation in the right superior frontal sulcus. Unique parameter of cerebral cortical changes, as measured using MRI, might underline impairments in distinct gait parameters in patients with INPH.

• The Journal of Korean Academic Society of Nursing Education
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• v.28 no.2
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• pp.137-146
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• 2022

Purpose: This study aimed to identify the associations between job stress, social support, and nursing professionalism among nurses taking postgraduate courses, and to explore the factors influencing their nursing professionalism. Methods: The participants were 121 nurses who were enrolled in graduate school master's or doctoral programs in Korea. Data were collected from June 30 to August 31, 2021, using an internet-based self-report questionnaire. The data were analyzed by descriptive statistics, independent t-test, one-way ANOVA, Pearson's correlation coefficient, and multiple regression analysis using the IBM SPSS 23.0 program. Results: The mean scores of job stress, social support, and nursing professionalism among the participants were 2.47 out of 4, 4.06 out of 5, and 3.47 out of 5, respectively. There were statistically significant differences in nursing professionalism among the participants according to the degree program (F=-2.76, p=.007) and the length of nursing career (F=4.35, p=.015). Their nursing professionalism showed a positive correlation with social support (r=.45, p<.001) and a negative correlation with job stress (r=-.43, p<.001). As a result of the multiple regression analysis, factors influencing nursing professionalism of the participants were found to be job stress (β=-.28, p=.003), social support (β=.23, p=.015), and the length of nursing career (β=.19, p=.018). The explanatory power of the model was 28.0% (F=12.62, p<.001). Conclusion: The present study suggests that organized efforts are needed to alleviate job stress and to increase social support for nurses in postgraduate courses in order to ultimately improve their nursing professionalism.

• Wind and Structures
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• v.37 no.3
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• pp.211-227
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• 2023

To investigate the non-Gaussian feature of fluctuating wind pressures on rectangular high-rise buildings, wind tunnel tests were conducted on scale models with side ratios ranging from 1/9~9 in an open exposure for various wind directions. The high-order statistical moments, time histories, probability density distributions, and peak factors of pressure fluctuations are analyzed. The mixed normal-Weibull distribution, Gumbel-Weibull distribution, and lognormal-Weibull distribution are adopted to fit the probability density distribution of different non-Gaussian wind pressures. Zones of Gaussian and non-Gaussian are classified for rectangular buildings with various side ratios. The results indicate that on the side wall, the non-Gaussian wind pressures are related to the distance from the leading edge. Apart from the non-Gaussianity in the separated flow regions noted by some literature, wind pressures behind the area where reattachment happens present non-Gaussian nature as well. There is a new probability density distribution type of non-Gaussian wind pressure which has both long positive and negative tail found behind the reattachment regions. The correlation coefficient of wind pressures is proved to reflect the non-Gaussianity and a new method to estimate the mean reattachment length of rectangular high-rise building side wall is proposed by evaluating the correlation coefficient. For rectangular high-rise buildings, the mean reattachment length calculated by the correlation coefficient method along the height changes in a parabolic shape. Distributions of Gaussian and non-Gaussian wind pressures vary with side ratios. It is inappropriate to estimate the extreme loads of wind pressures using a fixed peak factor. The trend of the peak factor with side ratios on different walls is given.