• Journal of Life Science
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• v.14 no.1
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• pp.72-81
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• 2004

Sexually matured guppies (Poeiria reticulata) were exposed to TBTCI (0.1, 0.32, 1, 3.2, 10, 25, 32, 50, 75 and 100 $\mug/l$) for 144 hours to determine the bioaccumulation rate and effects on the reproduction and behavior. The ratio of TBT residues to $\SigmaBTs\; (TBT:\SigmaBTs)$ was 67% or higher in all the guppies exposed to TBTCl, and the higher the level of TBTCl exposed, the higher the ratio of TBT:∑BTs, suggesting that the higher the level of TBTCl exposed, the lower the metabolism rate of the fish. TBTCl exposure led to a poor reproductivity and an abnormal sexual behavior in the fish, i.e. a reduced number of the male sexual sigmoid display and of spermatophore in the efferent duct was observed in the fish exposed to 0.1 $\mug/l$ and higher levels of TBTCl, and a decreasing ratio of the testicular spermatophore cyst to the whole germ cell cysts was observed in the fish exposed to 0.32∼10 $\mug/l$)of TBTCl. The reduced ratio of the spermatophore cyst seems to be an effect of the endocrine disrupter inhibiting spermiogenesis. In the fish exposed to 25 $\mug/l$ and higher levels of TBTCl, more serious effects, such as a rapid increase of mortality, the necrosis of most of the germ cells, great damages in Sertoli cells and epithelial cells of the efferent duct, a significant increase of abnormal swimming behavior, and a cessation of feeding were observed, which suggest the acute toxicity of TBTCl inhibiting not only the reproduction and behavior but also the survival of the fish itself.

• Journal of Gifted/Talented Education
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• v.24 no.2
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• pp.169-189
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• 2014

The purpose of this study was to compare elementary gifted student's academic stress, stress coping and academic burnout with those of general students and investigate the relationships between academic stress, stress coping and academic burnout. There is a significant meaning in promoting healthy growth and development by reducing academic stress and academic burnouts, as well as providing fundamental data to understand and mentor elementary gifted student and general students emotionally. The results obtained in this study were as follows. First, the results showed that the gifted students' academic stress, school stress, and after school academic stress were significantly lower than general students'. Second, the results showed that the elementary gifted students used more of active and socially supported ways to cope with stress while the general students use more of passive/evasive and aggressive ways to cope with stress. Third, the results showed that the score of gifted students' academic burnouts was significantly lower than that of regular students', and among general students, the students who spent more time than average time in the private education per week had significantly higher academic burnouts compared to the students who didn't. Fourth, the results showed that the elementary gifted students with high academic stress used more passive/evasive and aggressive ways to cope with stress. As a result of correlation analysis, it appeared a positive correlation between academic stress and academic burnout. Hierarchical multiple regression showed that academic stress and stress coping affected on academic burnout significantly.

• Applied Biological Chemistry
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• v.23 no.2
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• pp.123-130
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• 1980

Thiamine derivatives of thiamine tetrahydrofurfuryl disulfide (TTFD) and thiamine propyl disulfide (TPD) were obtained in a good yield and purity by use of thiothiamine $(SB_1)$ and also described in details for the preparing sodium tetrahydrofurfuryl thiosulphate (Bunte's salt) with and without KI. The optimum reaction conditions for the preparation of TTFD was set in which the Box-Wilson plan was applied. The reaction conditions are as follows; 1. pH value of aqueous solution of thiol type of $B_1{\cdot}HCl;12.09$ 2. Quantity of Bunte's salt (to $B_1{\cdot}HCl\;20G$); 35.01g 3. Reaction temperature; $15.59^{\circ}C$ Studies on ultraviolet absorption were made at various pH and showed that the absorption maxima are shifted with change of pH. The absorption maxima are at $244{\sim}246nm,\;234{\sim}235nm$ in TTFD, and $245{\sim}246nm,\;233{\sim}235nm$ in TPD. The structure was proved by the infrared spectral evidence. Quantitative determination was studied.

• The Journal of the Petrological Society of Korea
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• v.4 no.1
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• pp.1-19
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• 1995

In order to characterize the petrogenesis of the E-W trending Imjinganag belt, we studied the metamorphic rocks of the Yeoncheon Group near its type locality, Yeoncheon - Cheongok area, belonging to the southern part of this fold-thrust belt. The Samgot Formation of the Yeoncheon Group consists of calc-silicate and metapsammitic rocks together with amphibolite and amphibole gneiss. Layers of these metamorphic rocks concordantly occur in a wide area with its length greater than 15 km along their strike direction. Major mineral assemblages of the amphibolite are hornblende + plagioclase ${\pm}$ garnet ${\pm}$ diopside ${\pm}$ biotite ${\pm}$ quartz. Accessory rutile and ilmenite are characteristically replaced by titanite. Metamorphic temperatures and pressures estimated from the garnet - hornblende - plagioclase - quartz geothermo-barometers are 632-$736^{\circ}C$ and 7.9-11.1 kbar, respectively. Thus, the regional metamorphism of the study area belongs to the upper amphibolite facies. Furthermore, Sm-Nd and Rb-Sr data of garnet, plagioclase, and whole rock of an amphibolite define mineral isochrons of $231{\pm}30$ Ma and $222{\pm}24$ Ma, respectively, suggesting the Triassic metamorphism. These results are consistent with P-T conditions and metamorphic ages reported in the Shandong Peninsula, and support the hypothesis that the Chinese collision belt may extend into the Imjingang belt in the Korean Peninsula.

• The Journal of the Petrological Society of Korea
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• v.4 no.1
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• pp.49-58
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• 1995

Staurolite-biotite-andalusite-garnet (SBAG) assemblage and its sub-assemblages (SBA and SBG) commonly occur in the Dueumri Formation near the Chunyang granite, belonging to andalusite and sillimanite zones. The occurrence of the SBAG mineral assemblage is unusual because it is univariant in the $K_2O-FeO-MgO-Al_2O_3-SiO_2-H_2O$ (KFMASH) model system. We used projection and singular value decomposition (SVD) methods to investigate the equilibrium relationship between SBAG and its sub-assemblage. The SVD modelling of single specimen containing the SBAG assemblage suggests no reaction relationship with respect to mass-balance. Thus, the SBAG assemblages are stabilized by non-KFMASH component. On the other hand, the AFM-Mn projection suggests a reaction relationship between SBAG and its sub-assemblage because they intersect each other in this composition space. The SVD modelling, however, suggests no reaction relationship between these assemblages. Thus, the SBAG assemblages are likely to be stabilized by the variation in bulk-rock composition and/or 1.1~2,. The stable occurrence of staurolite in the sillimanite zone is compatible with pressure estimates from the garnet-plagioclase-biotite-muscovite geobarometer.

• Tunnel and Underground Space
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• v.9 no.1
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• pp.48-55
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• 1999

One of the major roles of concrete lining is the supplementary support of ground load. Therefore, if there are cracks or deformation found in the lining, the causes should be carefully examined. Tunnel Soundness Evaluation System (DW-TSES) was developed to meet such requirements. Main facility of the system was intended to find the probable causes on the basis of the apparent changes in lining and the environmental conditions. It also includes facilities for evaluating the soundness of a tunnel and indicating the method for repair or reinforcement. The characteristic feature of damages is used for reasoning in case of deterioration and leakage, and artificial neural network is used in external pressure. This process depends on the results of the case analyses and FDM, which have a collection of the typical features of different types of damages as well as the unusual changes caused by the external pressure. The comparison of the outputs of this system with those of expert's diagnoses draws the following conclusions. 1) Artificial neural network was a suitable tool to find to causes of damages by external pressure. 2) The environmental conditions improved the accuracy in reasoning. 3) The result of finding causes and evaluating soundness was helpful to suggest effective methods concerning tunnel maintenance.

• Tunnel and Underground Space
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• v.30 no.4
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• pp.404-416
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• 2020

An analytical procedure for calculating the failure load of a V-shaped rock notch under two-dimensional stress conditions was developed based on the slip-line plastic analysis method. The key idea utilized in the development is the fact that the α-line, one of the slip-lines, extends from the rock notch surface to the horizontal surface outside the notch when the rock around the notch is in the plastic state, and that there exists an invariant which is constant along the α-line. Since the stress boundary condition of the horizontal surface outside the rock notch is known, it is possible to calculate the normal and shear stresses acting on the rock notch surface by solving the invariant equation. The notch failure load exerted by the wedge was calculated using the calculated stress components for the notch surface. Rock notch failure analysis was performed by applying the developed analytical procedure. The analysis results show that the failure load of the rock notch increases with exponential nonlinearity as the angle of the notch and the friction of the notch surface increase. The analytical procedure developed in this study is expected to have applications to the study of fracture initiation in rocks through wedge-shaped notch formation, calculation of bearing capacity of the rock foundation, and stability analysis of rock slopes and circular tunnels.

• Korean Security Journal
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• no.17
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• pp.157-172
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• 2008

The purpose of this research is to suggest a construction device that can transform a public safety, security service, security system on counter- terrorism device system, from government leading type to private management type. There are purpose on this thesis to research for the bringing up counter-terrorism experts certification system and about all sorts of developed device among our country's counter-terrorism situation and through comparing developed country's private security's developing device. This summary of thesis is like below. First we need to establish total counter-terrorism center, like developed country on national corresponding strategy. Second, we need to make an organization as a country security department unified as an America's President directly belonging organization. Third, it is to legislate about an counter-terrorism. Fourth, we need to make a coorperate system according to counter-terrorism duty come under private management, so that can recover a trust among people. Fifth, a terror warning system is necessary. Private security's mutual relationship and developing devices is First, it is necessary to bring up counter-terrorism expert. Second, it is necessary to bring in counter-terrorism experts certification system. Third, counter-terrorism research center that come under private management is necessary. It is considered that various research need to be continued after by bringing up counter-terrorism experts, transforming a consciousness, counter- terrorism education, building an equipment and education center, not for a special group, that can minimize human infringement.

• Korean Journal of Psychosomatic Medicine
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• v.15 no.1
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• pp.22-28
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• 2007

The pregnancy and postpartum period appear to be a time of heightened vulnerability for the development of major depression in some women. Postpartum depression affects 10% of women within a few weeks immediately postpartum. Postpartum depression is associated with disturbances in the mother-infant relationship, which in turn have an adverse impact on the course of child cognitive and emotional development. Depression during pregnancy is also common, although it has been relatively neglected. Psychopathological symptoms during pregnancy have physiological consequences for the fetus. Understanding the aetiology of perinatal depression requires integrating of multiple psychosocial and biological risk factors. The treatment of depressed pregnant women requires skilled decision making by psychiatrists. Risk-benefit analysis is appropriate method for intervention fur depression in pregnancy. Effective treatments for depression in pregnancy include psychotherapy, antidepressant medication and electroconvulsive therapy. In treatment of postpartum depression, the biological, psychological, and social interventions are included. Prescribing antidepressants(such as fluoxetine), estrogen in severe and chronic cases, and counselling can be effective for improving maternal mood and aspects of infant outcome. Ongoing research is directed to further elucidating neurohormonal and psychosocial contributions to depression during pregnancy or postpartum. Screening for risk factors and symptoms for depression need to be incorporated into antenatal and pediatric clinics.

• Environmental and Resource Economics Review
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• v.19 no.4
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• pp.853-874
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• 2010

This study examines the acceptability of nuclear facilities using the latent class analysis. Even though, nuclear power is useful in terms of economic and energy security aspects, it is very difficult to expand the existing nuclear power plants or build a new one. Many studies analysed the cause of unacceptability of nuclear facilities but it has not been focused how large portion of people are divided pro and con. It is very important to know the distribution of people by the attitude toward nuclear facilities in order to meet the long term National Energy Plan. Through the latent class analysis with 1,025 respondents, people are classified into three groups(favor-class, support-class, opposition-class). The favor-class is the largest group which has moderate good attitudes toward the nuclear facilities in terms of economy, cleanness. and necessity but concerns a little about safety. The second largest group is the support-class which comprises 1/4 portion of people. The people in the class show the aggressive support for the nuclear facilities. 15% of the respondents belong to the opposition-class which show the negative attitudes to expansion of neclear facilities. In order to increase the acceptability of nuclear faculties, the most urgent work for the government to do is to less people's concern about nuclear safety.