• Journal of the Korea Concrete Institute
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• v.29 no.4
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• pp.379-387
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• 2017

The objective of this study is to develop sustainable PVA fiber-reinforced cementitious composites (FRCCs) that could exhibit comparable strength level to normal PVA FRCCs with no recycled materials. To evaluate mechanical properties of the FRCCs, compressive, flexural and direct tensile tests were conducted. In addition to the test, to calculate amount of carbon dioxide ($CO_2$) emission at the stage of manufacturing the FRCCs, life cycle inventory data base (LCI DB) were referenced from domestic and Japan. From the test results, the mechanical properties such as compressive, flexural and direct tensile strengths were decreased as the replacement ratio of recycled materials increased. And it was determined that the amount of $CO_2$ emission was reduced for the specimens with higher water-binder ratio (W/B) and replacement ratios. It was also found that binder intensity ($B_i$) value was higher as replacement ratio of fly ash (FA) increased. This result means that larger amount of FA is need to deliver one unit of a given performance indicator (1 MPa of strength) of FRCCs compared to that of ordinary portland cement (OPC). As a result, it could be concluded that FRCCs with W/B 45% replaced by FA 25% and recycled sand (RS) 25% is desirable for both target performance and $CO_2$ emission.

• The Journal of the Korea Contents Association
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• v.16 no.10
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• pp.235-254
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• 2016

This study examined the mediation effect of the family resilience between the family stress and social problem solving ability of the women social worker and welfare specialist, considering that women's middle age needs the resilience including the adaptation, reestablishment in the family life cycle. The sampling target was the 328 women social workers in the middle age, and it performed the Sobel Test for the mediation effect verification after enforcing the multiple regression analysis, next, it is same. Firstly, the economic problem was most highly severe among the family stress subfactor. Secondly, there was altogether the part mediation effect of the family resilience' subfactors, ie, communication processes, belief systems and organizational patterns between the family stress and social problem solving ability. In conclusion, if the family stress which the middle aged women social worker confronted was accurately analyzed and the family is intervened so that the family resilience functions properly, the social problem solving ability would be able to be improved.

• Journal of Korean Academy of Nursing
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• v.12 no.2
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• pp.80-90
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• 1982

This study was undertaken to determine the influence of a chronic disease on body image, and to show that body image is directly related to one's self concept. Body image is the concept of one's own body based on present and past perception, and is elated to one's self concept. Body image is a dynamic concept constantly changing throughout the life cycle but it changes greatly in illness, surgery, and accident. The child with a chronic disease experiences pain and immobilization due to illness and he/she experiences a strange environment in the hospital. illness often brings feeling of frustration and loss of self-esteem. Therefore this study was done to compare the body image of a child with a chronic disease（Asthma), with that of a normal healthy child, and to determine the relationship between the body image and self concept. The subjects in this study were 36 children being treated for asthma at the allergy clinic of Y University Hospital in Seoul (patient group) and 44 children attending elementary school in Kwanak Ku Seoul (normal healthy group). For the measurement of the body image, the researcher used Secord & Jourard's Body Cathexis Scale, and another scale which was constructed after reading about Osgood's Semantic Differential Method. For the measurement of the self concept, the researcher used Jacox & Stewart's Health Self Concept. The period for data collection was from October 7th to October 27th, 1982. The analysis of data was done by use of Percentage, t-test, Chi-square test, Pearson Correlation Coefficient and ANOVA, The results of the study were as follows: 1. The first hypothesis,“That the chronically ill (Asthma) child will have a more negative body image than the normal healthy child.”was supported. 2. The second hypothesis,“The more negative the body image, the lower the self concept.”was also supported. 3. The researcher failed to obtain statistically significant results in the analysis of the general characteristics which affect the body image except in the case of the older child as compare to the younger Child having a mole positive body image (r=.2751, r=.2481, p<.05). However it was found that, 1) Boy's have a more positive body image than girls (Mean=〔37.81, 141.09〕,〔37.00, 126.54〕), 2) The child who has been hospitalized has a more negative body image than the child who has never been hospitalized (Mean=〔33.25, 122.45〕,〔35.68, 129.93〕). 3) The younger the child when the disease is discovered and diagnosed, the more negative the body image (Onset of illness: Mean=〔31.44, 117.33〕,〔34.00, 103.50〕, 〔35.75, 140.38〕,〔36.33, 130.00〕, Time of Diagnosis: Mean=〔29.00, 117.33〕,〔33.89, 115.00〕,〔33.36, 124.93〕,〔37.10, 139. 20〕). In conclusion the chronically ill(.Asthma) child has a more negative body image than the normal healthy child, and the more negative the body image the lower the self concept. Therefore the concept of body image is useful in understanding the influences of chronic disease on body' image and self concept.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.26 no.6
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• pp.431-438
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• 2013

The systemization of construction information is required over whole life cycle of facilities to improve productivity of construction industry. BIM(Building Information Modeling) is a technology to manage information based on 3D information model. It has been actively suggested as one of the alternatives. However, it may be currently concentrated on the large project while the small and medium project based on BIM are slightly treated in indifference. In the case of small and medium project, the loss of information has been occurred more seriously than large project. However, it is hard to introduce BIM to the small and medium companies due to the lack of investment resources. This study has been performed to set up information management system based on BIM considering characteristics of small and medium project without excessive investment. In this study, pseudo BIM is defined as BIM for small and medium project. The concept of pseudo BIM has been suggested. The PLIB of ISO and construction information classification system of MOLIT in Korea are used to construct data dictionary for pseudo BIM. A pilot test is performed to verify the effectiveness of pseudo BIM.

• Journal of Convergence for Information Technology
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• v.7 no.5
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• pp.1-13
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• 2017

It is revealed that there are more registered disabled people in our country who have their disability because of acquired factors such as accidents than because of innate deformity. This phenomenon will continue and the incidence of acquired disability will increase more and more. Even though there is noticeable change, the social recognition toward the disabled is still negative. Particularly, university students are in the early adulthood according to the development of life-cycle, and this is the period that people have diverse social relationships, depart from unified frame and work in various fields, and set up their own thoughts and ideology with knowledge and skills acquired from university education. Therefore, in this study, we are going to search the recognition of the university students, who are in the previous period of entering into the society, toward the disabled, and if they have negative prejudice or attitude against the disabled, we are going to find the ways to improve on their awareness positively. The subjects of the survey were randomly selected among 230 out of total 250 students by visiting thirteen universities in Chungcheong Province, and were analyzed by using SPSS (ver. 18.0) program. T-test and One-way ANOVA were used as analytical methods to look into the difference of analysis of frequency, descriptive statistic, reliability analysis and attitudes for comprehending sociodemographic characteristics of the subjects of the survey. In conclusion, it has to be not a temporary or event-like training, but a training that makes people have positive recognition and attitude towards accurate information, knowledge, human rights, disability, and diversity. This thesis has a limitation to be generalized to the university students all over the country since the region is limited to a certain area.

• Journal of the Korean Electrochemical Society
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• v.2 no.4
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• pp.218-220
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• 1999

The performance of the Electric Vehicle and Hybrid Electric Vehicle depends on that of the battery pack composed of series connected batteries. And thermal property is one of the main factors which decide the performance of the battery pack. So heat generation rate from the battery under the various driving mode must be measured as precise as possible because thermal characteristics of the battery affect the driving performance and battery pack's life cycle. Besides, to design and develop the battery thermal management system for the EV and HEV, the measurements of the thermal properties of the batteries are needed. However, the established calorimeter is not adequate to test an EV's battery because its cavity is too small to accommodate the EV's battery. Therefore we developed the calorimeter to test the thermal property of the EV's battery. Its cavity size is 120mm long, 75mm wide and 200mm high. The calorimeter is calibrated by the dummy cell which generates the heat rate from zero to 200W. The measuring accuracy of the calorimeter is within $2\%$ and its voltage stability is 2.5mV in the constant temperature bath.

• Journal of Radiation Industry
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• v.5 no.3
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• pp.211-220
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• 2011

This study was carried out to develop salt tolerant varities of rapeseed (Brassica napus L.) which can be grown in the high salty reclaimed land. The seeds of three varieties 'Naehan', 'Tammi', and 'Halla' were treated by proton ion beams and gamma rays with 0 to 2,000 Gy. For the selection of salt tolerant lines, emergence and survival rate, and growth characteristics of $M_2$ to $M_4$ generations were investigated in the Saemangeum reclaimed fields with the different salt concentrations. The lines with potential salt tolerance were selected in the $M_4$ generation and tested indoor for their growth characteristics. There was no significant changes in the soil pH for $M_4$ generation during growth period. However, soil EC was higher in early spring than sowing period (mid October). In $M_4$ generation test, the seeds of original and selected line showed high rates of emergence and survival, as determined one month after sowing. After wintering, however, the original varieties showed the significant reduction in the survival rate, while the selected lines showed a higher survival rate and good growth, leading to the completion of their life cycle. Consequently we selected 9 lines from $M_4$ generation with better performance in growth and yield. Soil EC was $2.8{\sim}4.3dS{\cdot}m^{-1}$ during $M_4$ generation growth period. The laboratory test of the lines selected from $M_4$ generation was made for their salt tolerance potential. The selected lines showed higher chlorophyll and proline contents than the original varieties. There was also no significant difference in the emergence rate of seed between the original and selected varieties. In 200 mM natural sea salt, the $N{\gamma}600-21-1-641$ line derived from 'Naehan' was the highest in growth rate, leaf chlorophyll and proline contents. $T{\gamma}800-20-2-461$ line derived from 'Tammi' didn't show significant difference in growth rate compared to original variety in 200 mM and withered in 250 mM like other lines as time passed. $H{\gamma}200-7-1-740$ line showed similar growth and chlorophyll content compared to its original variety.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.6
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• pp.751-762
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• 2022

Welded head studs are mainly used as shear connectors to bond steel girders and concrete slabs in steel-concrete composite bridges. For welded shear connectors, environmental problems include noise and scattering dust which are generated during the removal of damaged or aged slabs. Therefore, it is necessary to develop demountable shear connectors that can easily replace aged concrete slabs for efficient maintenance and thus for better management of environmental problems and life cycle costs. The buried nut method is commonly studied in relation to bolted shear connectors, but this method is not used in civil structures such as bridges due to low rigidity, low shear resistance, and increased initial slip. In this study, in order to mitigate these problems, a demountable bolted shear connector is proposed in which the buried nut is integrated into the stud column and has a tapered shape at the bottom of an enlarged column shank. To verify the performance of the proposed demountable stud bolts in terms of static shear strength and slip displacement, a horizontal shear test was conducted, with the performance outcomes compared to those of conventional welded studs. It was confirmed that the proposed demountable bolted shear connector is capable of excellent shear performance and that it satisfies the slip displacement and ductility design criteria, meaning that it is feasible as a replacement for existing welding studs.

• Journal of Life Science
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• v.27 no.11
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• pp.1331-1339
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• 2017

DNA barcoding is the identification of a species based on the DNA sequence of a fragment of the cytochrome C oxidase subunit I (COI) gene in the mitochondrial genome. It is widely applied to assist with the sustainable development of fishery-product resources and the protection of fish biodiversity. This study attempted to verify horse-head fish (Branchiostegus japonicus) and fake horse-head fish (Branchiostegus albus) species, which are commonly consumed in Korea. For the validation of the two species, a real-time PCR method was developed based on the species' mitochondrial DNA genome. Inter-species variations in mitochondrial DNA were observed in a bioinformatics analysis of the mitochondrial genomic DNA sequences of the two species. Some highly conserved regions and a few other regions were identified in the mitochondrial COI of the species. In order to test whether variations in the sequences were definitive, primers that targeted the varied regions of COI were designed and applied to amplify the DNA using the real-time PCR system. Threshold-cycle (Ct) range results confirmed that the Ct ranges of the real-time PCR were identical to the expected species of origin. Efficiency, specificity and cross-reactivity assays showed statistically significant differences between the average Ct of B. japonicus DNA ($21.85{\pm}3.599$) and the average Ct of B. albus DNA ($33.49{\pm}1.183$) for confirming B. japonicus. The assays also showed statistically significant differences between the average Ct of B. albus DNA ($22.49{\pm}0.908$) and the average Ct of B. japonicus DNA ($33.93{\pm}0.479$) for confirming B. albus. The methodology was validated by using ten commercial samples. The genomic DNA-based molecular technique that used the real-time PCR was a reliable method for the taxonomic classification of animal tissues.

• The Korean Journal of Malacology
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• v.22 no.2
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• pp.125-134
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• 2006

We investigated the reproductive cycle of the hard clam, Meretrix petechialis with its gonadal development by histological observations. The seasonal changes in biochemical component of the adductor muscle, visceral mass, foot muscle and mantle of the clam were studied by biochemical analysis, from January to December, 2002. The reproductive cycle of this species can be divided into five successive stages: early stage (January to March), late active stage (February to May), ripe stage (April to August), partially spawned stage (July to August) and spent/inactive stage (September to January). Total protein content in the visceral mass was over two times higher than that in the adductor muscle. Monthly changes of total protein content in the adductor muscle were not statistically significant (ANOVA, p = 0.071), while the changes in the visceral mass were significant (p < 0.001). Total protein content in visceral mass was higher during the early active, late active, and ripe stages (from January to May), while the lowest in July. Glycogen content in the adductor muscle was higher than that in the visceral mass. Monthly changes in glycogen contents were statistically significant in both adductor muscle (F = 237.2, p < 0.001) and the visceral mass (F = 64.04, p < 0.001). Glycogen content in the adductor muscle was the highest in the ripe stage (April). Its content was lower in the partially spawned and the spent/inactive stages (June-September). Glycogen contents in the visceral mass were relatively lower until the early active stage, while the highest in the late active stage. RNA content was higher in visceral mass than that in the adductor muscle. Monthly changes in RNA contents were significant in both adductor muscle (F = 195.2, p < 0.001) and visceral mass (F = 78.85, p < 0.001). RNA content in the adductor muscle was high in the early active stage (January-February), and then it decreased rapidly in the late active stage (March-April), thereafter, slightly increased during the partially spawned stage (June-July). RNA content in the visceral mass reached a maximum during the ripe stage (May), and then it decreased rapidly during the partially-spawned stage (June-July). There was significant positive correlation in total protein contents between adductor muscle and visceral mass (r = 0.715, p = 0.020). However, there was no correlation between adductor muscle and visceral mass in glycogen (p = 0.550), while a negative correlation was found between the adductor muscle and visceral mass in RNA (p = 0.518) contents. Especially, changes in RNA content showed a negative correlation between the adductor muscle tissue and visceral mass. Therefore, these results suggest that the nutrient content of the adductor muscle, visceral muscle and foot muscle changed in response to gonadal energy needs.