• The Journal of Korean Medicine
• /
• v.27 no.2 s.66
• /
• pp.145-154
• /
• 2006

Objectives : Methods to evaluate obesity are growing to be important in studying links between health and disease. Physicians are using BMI (body mass index) to evaluate obesity, but they can't know how much fat the body has by using that method. Even though there are several assessments, there are different scales, so patients are diagnosed as obese, by some but not by others. These studies are limited in evaluating obesity; it is necessary to study based on new knowledge. According to Oriental Medical Theory, obese people are categorized into 3 types, Fei, Kao and Liu Ren. They have different pathology and body shapes than non-obese people. The relationship between Oriental Medical Theory and BMI and assessment of body fat is a fundamental need to easily approach and treat obesity. Methods : At 00 Oriental Medical Center, 145 female subjects who intended to lose weight were given physical tests and grouped into 5 types of obesity. The physical tests were height measurement, BMI, body composition (body fat mass and lean body mass), skin elasticity and physical strength tests. One-way analysis of variance was done to compare the means of physical tests between the five types of obese women. There was some relationship between characteristics of the five types based on physical tests and Fei, Kao and Liu Ren based on Oriental Medical Theory. Least significant difference (LSD) was used in multiple comparisons. Results : 1. According to the skin elasticity test, obesity type 5 placed between obesity types 3 and 4 and obesity types 1 and 2. Obesity types 3 and 4 were in the low skin elasticity result group; obesity types 1 and 2 were in the high ones (p<0.1).Based on Oriental Medical Theory, Fei Ren and Kao Ren can be distinguished by skin elasticity degree. This result should form the basis of obesity diagnosis. 2. According to Oriental Medical Theory, Fei Ren is smaller than others. Based on height measurement, obesity types 3 and 4 were significantly lower than other obesity types (p<0.1), so there is a relationship between Fei Ren and obesity types 3 & 4. 3. There were significant differences between obesity type 2 and obesity type 4 in the body fat mass result (p<0.1). This study did not have large enough a sample size to distinguish Liu Ren. Conclusions : Further clinical research is necessary to study measurement methods of body shape type and skin elasticity for distinguishing Fei Ren from Kao Ren. The diagnosis and treatment based on the relationship of these types should be studied further.

• Journal of the Korean Society of Radiology
• /
• v.17 no.6
• /
• pp.919-927
• /
• 2023

Elastography utilizes the fact that the tissue of a malignant tumor is harder than that of a benign tumor and increases the specificity of diagnosis according to the elastic modulus of the tumor, helping to reduce unnecessary biopsies. However, the reliability of elastography can be influenced by the equipment used and the examiner's skills. In this study, the researchers analyzed the reproducibility of elastography by evaluating phantom images when measuring the elasticity values repeatedly. Phantoms were created using silicone and gelatin with different levels of stiffness, and they were inserted at varying depths from the surface. The elasticity values were measured using shear wave elastography. The study aimed to determine whether the reproducibility of elasticity values remains consistent depending on the stiffness and depth of the lesions. The experimental results showed that there was no statistically significant correlation between the elasticity values obtained through shear wave elastography and the depth or stiffness of the lesions. However, in the lesions with the lowest stiffness, the elasticity values were statistically significant (p<0.001) and showed a high correlation with the depth of the lesions. Although there were variations in the measured elasticity values based on the differences in lesion stiffness and depth, these differences did not significantly impact the diagnosis. Therefore, shear wave elastography remains a reliable diagnostic method, and it is suggested that it can be helpful in the diagnosis of breast lesions.

• Journal of Korean Society of Steel Construction
• /
• v.15 no.2
• /
• pp.137-145
• /
• 2003

In this study, direct tensile fatigue tests of the PS bar were performed in terms of diameter, minimum stress level, and maximum stress level. In the static test, the stress - strain curve and ultimate streng th of the PS bar were determined. Results of the fatigue test indicate that the diameter of the PS bar was not influenced by fatigue life. Minimum stress also had quite an influence on the fatigue of the PS bar. Thus, the fatigue characteristic equation was proposed in terms of stress range and minimum stress through statistical process. Strains on specimen that loaded direct tension were measured in the fatigue test, with the secant modulus of elasticity calculated from measured strains. The strain development consisted of three different stages, i.e., rapid increases during the initial fatigue life, uniform increases during the middle stage, and rapid increases until failure. The secant modulus of elasticity decreased during the fatigue life with increasing strain. However, stress level seemed to have no influence on the secant modulus of elasticity.

• Journal of Labour Economics
• /
• v.37 no.4
• /
• pp.25-57
• /
• 2014

Analysing the effects of expanded trade liberalization on the domestic labor market such as the flexibility of employment adjustment and the wage elasticity of employment etc. with industry base data, we get some important results as follows. The speed of employment adjustment in whole industries is turned out to be more rapid on the employee basis than on the whole worker basis. And the speed of employment adjustment is more rapid in the industries with high level of import ratio than those with high level of export ratio. In sum, viewing on the employee basis, the expanded trade liberalization makes the speed of employment adjustment slower slightly in individual industry level, and it is led mainly by the effects of export ratio rising. In case of the wage elasticity of employment, it becomes to be much higher as rates of openness or export ratios go higher, so the environment of jobless growth seems to be much more strengthened in this country.

• Journal of the Korean Wood Science and Technology
• /
• v.11 no.3
• /
• pp.3-13
• /
• 1983

Fiber mats were made at five density levels, using fibers from kraft pulp screening rejects, rice straw and a 50/50 mixture of the two. They were soaked in the sulfur compounds. Specimens cut from the composite panels were tested in flexure at time intervals for one year to study the effect of aging. Modulus of elasticity (MOE) and modulus of rupture (MOR) were determined. Under optimum conditions of fiber mat preparation and saturation with molten sulfur and modified sulfur, composites were produced which exhibited mechanical properties comparable to conventional fiberglass in some properties and superior to conventional wood-based composition boards, For example. the moduli of elasticity of the reinforced composites made from pulp screening rejects, with a density of 0.35 gm/$cm^3$, were greater than 1,000,000 psi as compared 800.000 psi for high-density hardboard (1.28 gm/$cm^3$). Modulus of rupture of the best reinforced composites was about 7,000 psi, comparable to 6,000 psi of high-density hardboard.

• Advances in concrete construction
• /
• v.13 no.2
• /
• pp.123-132
• /
• 2022

This paper aims to adapt Multilinear regression (MLR) to predict the strength and toughness of SIFCON containing various pozzolanic materials. Slurry Infiltrated Fibrous Concrete (SIFCON) is one of the most common terms used in concrete manufacturing, known for its benefits such as high ductility, toughness and high ultimate strength. Assessment of compressive strength (CS.), flexural strength (F.S.), splitting tensile strength (STS), dynamic elasticity modulus (DME) and impact energy (I.E.) using the experimental approach is too costly. It is time-consuming, and a slight error can lead to a repeat of the test and, to solve this, alternative methods are used to predict the strength and toughness properties of SIFCON. In the present study, the experimentally investigated SIFCON data about various mix proportions are used to predict the strength and toughness properties using regression analysis-multilinear regression (MLR) models. The input parameters used in regression models are cement, fibre, fly ash, Metakaolin, fine aggregate, blast furnace slag, bottom ash, water-cement ratio, and the strength and toughness properties of SIFCON at 28 days is the output parameter. The models are developed and validated using data obtained from the experimental investigation. The investigations were done on 36 SIFCON mixes, and specimens were cast and tested after 28 days of curing. The MLR model yields correlation between predicted and actual values of the compressive strength (C.S.), flexural strength, splitting tensile strength, dynamic modulus of elasticity and impact energy. R-squared values for the relationship between observed and predicted compressive strength are 0.9548, flexural strength 0.9058, split tensile strength 0.9047, dynamic modulus of elasticity 0.8611 for impact energy 0.8366. This examination shows that the MLR model can predict the strength and toughness properties of SIFCON.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1997.10a
• /
• pp.61-64
• /
• 1997

As construction technology advances, most of concrete structures are becoming larger and taller. Therefore, high strength and quality concrete is necessary for them. So, the proposal of using belite cement is investigated to satisfy high flowing, low heat, and high strength. In this study, the compressive strength, tensile strength, and modulous of elasticity of concrete using belite cement was considered according to the mix proposition condition as a water-cement ratio, unit cement content, and sand percentage.

• Journal of the Korea Concrete Institute
• /
• v.26 no.3
• /
• pp.377-384
• /
• 2014

Recently, the trend toward larger architectural structures continues and accelerates demand for Ultra High Strength Concrete (UHSC) which satisfies structural performance. However, UHSC has weakness in fire and the performance tests are required. In this paper, the change of mechanical properties of 100 MPa grade UHSC exposed to high temperatures ($20^{\circ}C{\sim}800^{\circ}C$) was observed to develop high temperature material model of UHSC: residual compressive strength, modulus of elasticity, property of stress-strain on monotonous loading and property of stress-strain on cyclic loading. In addition, TG/DTA and SEM Images analyses were performed to investigate chemical and physical characteristics of UHSC, and the results of this research were compared with those of previous studies. As a result, UHSC at the heating temperature of $300^{\circ}C$ showed a sharp decrease of residual compressive strength and modulus of elasticity. And It was shown that UHSC had a plastic behavior at more than $400^{\circ}C$ on the cyclic loading and revealed a same tendency in both monotonous and cyclic loading of all heating temperatures. In addition, through TG/DTA and SEM images analyses compared with those from previous studies, it was shown that the deterioration of concrete inner tissue, water evaporation and chemical reaction caused the decrease of residual compressive strength and modulus of elasticity.

• Magazine of the Korea Concrete Institute
• /
• v.8 no.4
• /
• pp.56-64
• /
• 1996

Steel fibres have been recognized to increase concrete's physical properties. The combination of high tensil strength, modulus of elasticity, stiffness modulus, and mechanical deformations provides concrete with increased ductility.

• Structural Engineering and Mechanics
• /
• v.18 no.4
• /
• pp.441-459
• /
• 2004

This paper explores the potential use of neural networks (NNs) in the field of contact mechanics. A neural network model is developed for predicting, with sufficient approximation, the contact lengths between the elastic layer and two elastic circular punches. A backpropagation neural network of three layers is employed. First contact problem is solved according to the theory of elasticity with integral transformation technique, and then the results are used to train the neural network. The effectiveness of different neural network configurations is investigated. Effect of parameters such as load factor, elastic punch radii and flexibilities that influence the contact lengths is also explored. The results of the theoretical solution and the outputs generated from the neural network are compared. Results indicate that NN predicted the contact length with high accuracy. It is also demonstrated that NN is an excellent method that can reduce time consumed.