• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.2
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• pp.21-29
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• 2014

This paper evaluates the shear strength, behavior and failure mode of reinforced concrete beams with deformed GFRP reinforcing bar. Four concrete beam specimens were constructed and tested. It was carried out to observe failure behavior and load-deflection of simply supported concrete beams subjected to four-point monotonic loading. In order to eliminate of the uncertainty by the shear reinforcements, any stirrups were not used. Variables of the specimens were shear span-depth ratio, effective reinforcement ratio. The dimensions of specimen is 3,300 or $1,950mm{\times}200mm{\times}240mm$. Clear span and shear span were 2,900mm, 1,000mm respectively. Shear span-depth ratios were 6.5 and 2.5. Effective ratios of Longitudinal GFRP reinforcing bar were $1.126{\rho}_{fb}$, $2.250{\rho}_{fb}$, $3.375{\rho}_{fb}$ and $0.634{\rho}_{fb}$. All beam specimens were broken by diagonal-tension shear and the ACI 440.1R, CSA S806 and ISIS, which was used to design test beams, showed considerable deviation between prediction and test results of shear strengths.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.1
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• pp.167-175
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• 2018

This research deals, The characteristics of mechanics and behavior of the tube structural systems, It has been investigated and considered conventional theory and case models, It has shown the suitability, The best location, And optimal shape of the unit module system, Considered variables materials of stiffness increase and decrease in hybrid tube structural systems this study carried out adapting analysis of statistical concepts. In a concrete way, This study exams the effect of reducing horizontal displacement and the shear lag phenomenon, Also, The purpose of this study is to utilize the basic data on the design and study of future high-rise hybrid structural system using this research. As a result, The framed- tube structural system does not effectively cope with horizontal behavior of high-rise buildings, The results of using varying material tested resistance factors and lateral loads in hybrid tube structural system, When each material is compared Bracing material is identified as a key factor in lateral behavior. In a ratio of material quantity framed-tube structural system, The level of sensitivity affecting the horizontal displacement is greater then the beam's column, In case of braced tube structural system, Braced appeared to be most sensitive in comparison of material quantity ratio in columns and beams.

• Science of Emotion and Sensibility
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• v.12 no.1
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• pp.55-64
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• 2009

Previous research has mainly investigated the characteristics of expertise by using typical and routine tasks. This research to overcome these limitations included non-routine task situations and observed expert and novice pilots' situation awareness (SA) performance in routine and non-routine situations. Additionally, whether the ability to aware or perceive the environmental information in limited time varies with the level of expertise was tested. To this end, $2^*2^*2$ mixed factorial design was employed, including expertise (novice/expert) as a between-subjects variable and normality of fight situation (routine/non-routine) and stimulus display time (long/short) as within-subjects variables. As results, there was no performance difference in routine situations between experts and novices, while experts significantly outperformed novices in non-routine situations. When the display time became shorter, overall SA accuracy was decreased for both experts and novices, whereas experts' performance remained significantly higher than novices in short and long conditions. When we examined the interaction between the normality of fight situation and stimulus display time, there was no difference between experts and novices in routine situations for both short and long conditions. In non-routine situations, however, experts' SA accuracy was significantly higher than novices both in short and long conditions. Overall, non-routineness of flight situation does not have any impact on SA performance of experts, while it has a critical impact on SA performance of novices.

• Journal of Biomedical Engineering Research
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• v.23 no.4
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• pp.269-279
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• 2002

When we inject a current into an electrically conducting subject such as a human body, voltage and current density distributions are formed inside the subject. The current density within the subject and injection current in the lead wires generate a magnetic field. This magnetic flux density within the subject distorts phase of spin-echo magnetic resonance images. In Magnetic Resonance Current Density Imaging (MRCDI) technique, we obtain internal magnetic flux density images and produce current density images from $\bigtriangledown{\times}B/\mu_\theta$. This internal information is used in Magnetic Resonance Electrical Impedance Tomography (MREIT) where we try to reconstruct a cross-sectional resistivity image of a subject. This paper describes numerical techniques of computing voltage. current density, and magnetic flux density within a subject due to an injection current. We use the Finite Element Method (FEM) and Biot-Savart law to calculate these variables from three-dimensional models with different internal resistivity distributions. The numerical analysis techniques described in this paper are used in the design of MRCDI experiments and also image reconstruction a1gorithms for MREIT.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.5
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• pp.82-91
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• 2011

In this study, 24 prototype specimens were tested to find out the shear behavior and strength of large anchorage system exceeding 50mm(2") in anchor bolt diameter($d_0$) and 635mm(25") in effective embedment depth($h_{ef}$) not addressed by ACI349-06 Appendix B. Test variables are anchor bolt diameter($d_0$ = 63.5, 76.2, 88.9mm), effective embedment depth($h_{ef}$=635, 762mm), and edge distance($c_1$=381, 508, 762mm). Concrete compressive strength is constant($f_{ck}$=38MPa). Test results ($V_{test}$) were overestimated by $V_{aci06}$(shear strength by ACI 349-06) and $V_{ccd}$(shear strength by CCD method). In large anchorage system exceeding 50mm(2") of anchor bolt diameter($d_0$) and 635mm(25") of anchor bolt effective embedment depth($h_{ef}$), the bolt diameter variation and effective embedment depth($h_{ef}$) has no influence on the shear strenth, But, according to the analysis results of the feature ratio on edge distance($c_1$) and anchor bolt diameter, the feature ratio become smaller, which means anchor bolt diameter is bigger, predicted ratio of test results and predicted equation is larger. It was found that anchor bolt diameter is immediate cause of deterioration in the shear capacity of large anchorage system. To improve and extend the validity of current design recommendations further theoretical and numerical work is needed.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.1-9
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• 2017

Spiral reinforcement in a circular column plays an effective role in the ductile behavior of a column through position fixing and buckling restraining of the longitudinal reinforcement, and confining core-concrete. Each country has suggested the minimum volumetric ratio of spiral reinforcement in order to secure the ductility of concrete columns. The minimum volumetric ratio of spiral reinforcement suggested by ACI 318-14 and the national concrete structure design standard was developed based on the theory of Richard et al. (1928); furthermore it has been used until now. However, their theory cannot consider the effects of high strength concrete and high strength reinforcement, and arrangement condition of the spiral reinforcement. In this study, a modified minimum volumetric ratio equation is suggested, which is required to improve the ductility of reinforced concrete circular columns and to recover their stress. The modified minimum volumetric ratio equation suggested here considers the effect of the compressive strength of concrete, the yield strength of spiral reinforcement, the cross sectional area of columns, the pitch of spiral reinforcements and the diameter of spiral reinforcement. In this paper, the validity of the minimum volumetric ratios from ACI 318-14 and this study was investigated and compared based on the results of uniaxial compression experiment for specimens in which the material strength and the spiral reinforcements ratio were used as variables. In the end of the study, the modification method for the suggested equation was examined.

• Herbal Formula Science
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• v.18 no.2
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• pp.227-239
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• 2010

Objective : The purpose of this study was to develop the simulator which can analyze the anti-inflammatory effects of herbs based on e-cell, or the virtual cell. Method : We have ensured the medical herbs and its active compounds by investigating the oriental medicine records and NBCI(Biomedicine database). Also we have developed the web-based search system for confirming database related to anti-inflammation. We have researched the cell signal pathway related with inflammatory response control and established the mathematical model of herb interaction on selected signal pathway in e-cell. Finally we have developed the prototype which can confirm the result of this model visibly. Results : We constructed the database of 62 cases of anti-inflammatory active compounds in 61 cases of medical herbs which have been known anti-inflammation effects in the paper, 16 cases of inflammatory factors, 10 cases of signal pathways related with inflammatory response and 6,834 cases of URL(Uniform Resource Locator) of referenced papers. And we embodied the web-based research system, which can research this database. User can search basic and detailed information of medical plants related with anti-inflammatory by using information system. And user can acquire information on an active compounds, a signal pathway and a link URL of related paper. Among investigated ten pathways, we selected NF-${\kappa}B$, which plays important role in activation of immune system, and we searched the mechanisms of actions of proteins which could be components of this pathway. We reduced total network into IKK-$I{\kappa}B$ - NF-${\kappa}B$, and completed mathematic modeling by using ordinary differential equations and response variables of $I{\kappa}B-NF-{\kappa}B$ signaling model network which is suggested by Baltimore Group. We designed OED(Ordinary Differential Equation) for response of IKK, $I{\kappa}B$, $NF-{\kappa}B$ in e-cell's cytoplasm and nucleus, and measured whether an active compound of medicinal plants which is inputted by an user would have a anti-inflammation effects in obedience to change in concentration over time. The proposed model was verified by using experimental results of the papers which are listed on NCBI.

• Journal of the Korean Home Economics Association
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• v.30 no.2
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• pp.21-34
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• 1992

The purpose of this study was to investigate (1) the effect of a masculine-feminine image in women's blouse·skirt on the perception of the wearer's occupational characteristics and suitability of the clothing for certain occupations, and (2) the effect of perceiver's sex, sex-role attitudes, and occupation on the perception formed by the function of clothing cues. The research design of the study consisted of 2(skirt color) × 2(blose color) × 3(masculine-feminine blouse forms) factorial desing of a blouse·skirt set. The experimental materials developed for this study were a set of stimuli and 2 response scales. The stimuli consisted of 12 drawings of woman's clothing made by systematic manipulations of 2 independent variabels (color and form) in drawings of blouse-skirt. The dependent variables were the perceptions of the wearer's occupational characteristics and suitability of the masculine or feminine clothing for certain occupations. Occupational characteristics were measured with a 7-point semantic differential scale composed of 21 bipolar adjectives. Perception of occupational suitability was assessed with 12 items of 5-point Likert type questions. In addition, the Bem Sex-role Inventory was used to assess perceiver's sex-role attitudes. The subjects consisted of 393 men and 389 women, whose occupations were classified as professionals, secondary school teachers, and white-collar workers. The data were analyzed by factor analysis, MANOVA, ANOVA, Mean and S.D. Three factors emerged to account for the perception of occupational characteristics. These factors were given the titles of (1) activity, (2) potency, and (3) evaluation factors. The activity factor was the largest, including 9 adjectives and accounting for 33.3% of the variance in blouse-skirt. On the blouse-skirt set, the form of the blouse had an effect on activity and evaluation for both sexes, while the color of the skirt had an effect on evaluation for both sexes as well as on potency for men. Strong effect of color and form on blouse·skirt were seen in perception of occupational suitability for the occupations of attorney(masculine) and secretary(feminine). On suitability for secondary school teaching occupations, the effects of color and form of blouse·skirt differed by sex of the subjects. Male subjects determined suitability by the color of the blouse, while female subjects determinied suitability on the basis of the form of the blouse. Perceiver's sex-role attitude and occupation partially influenced the perception of the wearer's occupational characteristics and suitability of the clothing for certain occupations.

• Korean Chemical Engineering Research
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• v.48 no.6
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• pp.717-724
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• 2010

The flash point is one of the most important physical properties used to determine the potential for fire and explosion hazards of flammable liquids. Despite the needs of the experimental flash point data for the design and construction of chemical plants, there is often a significant gap between the demands for the data and their availability. This study have built and compared two models of partial least squares(PLS) and support vector machine(SVM) to predict the experimental flash points of 893 organic compounds out of DIPPR 801. As the independent variables of the models, 65 functional groups were chosen based on the group contribution method that was oriented from the assumption that each fragment of a molecule contributes a certain amount to the value of its physical property, and the logarithm of molecular weight was added. The prediction errors calculated from cross-validation were employed to determine the optimal parameters of two models. And, an optimization technique should be used to get three parameters of SVM model. This work adopted particle swarm optimization that is one of heuristic optimization methods. As the selection of training data can affect the prediction performance, 100 data sets of randomly selected data were generated and tested. The PLS and SVM results of the average absolute errors for the whole data range from 13.86 K to 14.55 K and 7.44 K to 10.26 K, respectively, indicating that the predictive ability of the SVM is much superior than PLS.

• Hwankyungkyoyuk
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• v.11 no.2
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• pp.118-129
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• 1998

This survey is made to offer the fundamental data for the establishment of practical environmental education plan based on understanding of the change of the environmental awareness of elementary school students under the longitudinal-sectional research design. In this research, the questionnaire made by Kim Jong-ki in 1988 and by Kim Hak-Bong in 1993, is amended and filled up, which is used to the 624 numbers of fifth and sixth grade students lived in Seoul, Pyungtaek and Yangjugu. This research ares are devided into 5 ares which are the environmental general, environmental pollution, living environment, environmental education and consciouness of environmental crisis to humen beings. First, it is grasped general tendency and then is compared and analyzed the level of awareness by residence, sex, grade. stsdard of living parental academic, the background variation of parental job with the status in 1988 and 1933. The results are as follows: 1) The rate of interest for environmental pollution and population is reduced but the rate of interest for animal protection is increased. 2) In spite of reinforcement of environmental education In school, the numbers of the students who became to know some information about that from the class are diminished. 3) Even if the children are aware of sewage seriousely, the numbers of the students who answer it is caused by domestic sewage are a few. 4) On the environmental education area, the various materials of the are not utilized well in a class. 5) On the environmental crisis to the human beings the rate is much increased in 1993 ttan that of 1988 environmental contamination is the important cause of the human beings' crises but now the rate is reduced again. In other variables except the environmental contamination, it is increased the that of 1993 on the war, on population it is showed a tendency of reduction. The results of this study are as follows : 1) It is supposed that the education should be done only not for the knowledge of environmental education but for the practice of that - animal breeding, field experience of the ecological destruction places. 2) The various environmental education materials such as TV, VTR are demanded to give the students proper information about that and to educate sufficently. 3) The course of fields exploration for environmental education should be prepared under cooperation of the authorities concerned. 4) It has to be groped for an epoch-making teaching method and the training and the practice of teachers in order to reform environmental pollution.