• Journal of the Korea Concrete Institute
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• v.13 no.6
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• pp.527-535
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• 2001

The watertight property of concrete was examined, that is affected by the sort of self waterproofing admixture and the change of the addition ratio of admixture. Various self waterproofing admixtures were made by changing the mixing ratio of silica fume, zinc stearate and silica sand. The result showed as follows. As the adding ratio of self waterproofing admixture increases, the fluidity is increased and the setting time is delayed. While compressive strength of concrete with self waterproofing admixture A which is currently using is increased until the adding ratio of self waterproofing admixture reached 18kg/㎥ and decreased over 24 kg/㎥, that with self waterproofing admixture B, C and D which are developed are higher than that of A. Absorption is decreased as the adding ratio of self waterproofing admixture and the increasing of age in concrete. Especially, when self waterproofing admixture has a lot of zinc stearate, absorption is decreased manifestly. The property of permeability is similar to that of absorption; permeability is decreased as the adding ratio of self waterproofing admixture and the increasing of age in concrete. Consequently, when the ratio of silica fume, zinc stearate and silica sand in self waterproofing admixture is 1 : 2 : 1 and addition ratio of self waterproofing admixture is 6kg/㎥, the high quality concrete is obtained comparing to the concrete with existent self waterproofing admixture.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.3C
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• pp.271-280
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• 2008

M channel near-perfect-reconstruction(NPR) pseudo-QMF banks are a hybrid of conventional pseudo-QMF design and spectral factorization approach where the analysis and synthesis filters are cosine-modulated versions of the prototype-lowpass filter(p-LPF). However, p-LPF H(z) does not have linear-phase symmetry as well as magnitude-distortion optimization since it is obtained by spectral factorization of $2M^{-th}$ band filter $G(z)=z^{-(N-1)}H(z^{-1})H(z)$. A fair amount of attention, therefore, has been focused on the design of filter banks for reducing only alias-cancellation distortion without reconstructed-amplitude distortion. In this paper, we propose a new method for designing linear-phase p-LPF in NPR pseudo-QMF banks, which is based on Maxflat(maximally flat) FIR filters with closed-form transfer function. In addition, p-LPF H(z) is optimized in this approach so that the 2M-channel overall distortion response represented with $G(z)=H^2(z)$ approximately becomes an unit magnitude response. Through several examples of NPR pseudo-QMF banks, it is shown that the peek ripple of the overall magnitude distortion is less than $3.5{\times}10^{-4}\;({\simeq}-70dB)$ and analysis/synthesis filters have the sharp monotone-stopband attenuation exceeding 100 dB.

• The Journal of the Korea Contents Association
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• v.18 no.6
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• pp.652-666
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• 2018

The purpose of this study was to investigate systematic review and meta-analysisto identify exercise intervention effect applied to patients who underwent lung resection with lung cancer. A total of 1,322 publications were searched from 1990 to 2016 through domestic and foreign electronic databases, and the final 13 publications were selected through literature selection process. Finally, eight RCT (randomized controlled trial) and five NRCT (non-randomized controlled trial) were identified, including 925 participants. The results of the meta-analysis of the effect sizes of the intervention on the outcome variables showed that the health-related quality of life EORTC QOL-C13/30 (the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire) (MD-0.50 95 % CI -0.83-0.18) and SF-36 PCS (the Medical Outcomes 36-Item Short Form Health Survey PCS) (MD 0.75, 95 % CI 0.41-1.10) in the intervention group were significantly higher than the control group. The results of this study suggest that exercise interventions can potentially improve the quality of life of patients who underwent lung resection with lung cancer.

• Korean Journal of Plant Tissue Culture
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• v.25 no.4
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• pp.283-288
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• 1998

The bialaphos is a potent inhibitor of glutamine synthease in higher plants and is used as a non-selective herbicide. We have used the bialaphos resistant gene(Bar) encoding for an acetyltransferase isolated from Streptomyces hygroscopicus SF1293. Callus derived from mature seeds of rice(Oryza sativa L. cv. Dong Jin) were co-cultivated with Agrobacterium tumefaciens EHA101 carring a plasmid pGPTV-HB containing genes for hygromycin resistance (HygR) and Bar. Transgenic plants showing in vitro resistance to 50 mg/L hygromycin and 10 mg/L bialaphos were obtained by using a two-step selection/regeneration procedure. Transformation efficiency of rice was about 30% which was as high as reported in other dicotyledons. Progenies ($\textrm{T}_{1}$ generation) derived from primary transformant of 17 lines were segregated with a 3 resistant : 1 sensitive ratio in medium containing hygromycin and bialaphos. Stable integration of Bar gene into chromosomal DNA was proven by Southern blot analysis of genomic DNA isolated from $\textrm{T}_{2}$ progenies. Transgenic plants ($\textrm{T}_{3}$) grown in the field were resistant to bialaphos (Basta) at a dosage lethal to wild type plants.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.3
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• pp.72-83
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• 2022

This paper studied the effect on the microstructure, electrical properties, and compressive strength of cement mortar containing carbon fiber (CF) and steel fiber (SF), which are conductive materials. The resistivity of conductive fiber-reinforced cement mortar (FRCM) was measured using the 4-probe method, and the compressive strength was measured based on the compression test. Their performance was compared and reviewed with plain mortar (PM). Furthermore, the surface shape and composition of the fracture surface of the conductive FRCM were analyzed using a scanning electron microscope (SEM) and an energy disperse X-ray spectrometer (EDS). The results showed that the resistivity gradually increased as the curing time increased in all specimens, whereas the resistivity decreased significantly as the fiber volume fraction increased. Adding steel fibers up to 1.25% did not affect the resistivity of cement mortar considerably. On the contrast, the resistivity of carbon fiber was somewhat decreased even at low contents (ie, 0.1 to 0.3%), and thereafter, it was significantly decreased. The percolation threshold of the conductive CFRCM containing CF used in this experiment was 0.4%, and it is judged to be the optimum carbon fiber dosage to maximize the conductive effect while maintaining the compressive strength performance as much as possible. For the surface shape and composition analysis of conductive FRCM, the fracture surface was observed through SEM-EDS. These results are considered to be very useful in establishing the microstructure mechanism of reinforcing fibers in cement mortars.

• BMB Reports
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• v.45 no.1
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• pp.20-25
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• 2012

The present study aimed to investigate the function of translationally controlled tumor protein (TCTP) in the regulation of Oct4 in mouse embryonic carcinoma P19 cells and mouse J1 embryonic stem (ES) cells. The mRNA level of endogenous TCTP in somatic cells was 2-4 folds higher than that in pluripotent P19 and J1 ES cells. Overexpression of TCTP in mouse pluripotent cells not only reduced the level of Oct4 transcription, but also decreased the pluripotency of stem cells. The N-terminal end of TCTP (amino acids 1-60) played an important role in suppressing the Oct4 promoter. Moreover, overexpression of TCTP in P19 cells suppressed the Oct4 promoter activity in a dose- and a time-dependent manner. In addition, knockdown of TCTP by small interfering RNA increased the expression of Oct4. Our study indicates that TCTP downregulates the Oct4 expression by binding the Sf1 site of Oct4 promoter in mouse pluripotent cells.

• Bulletin of the Korean Mathematical Society
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• v.22 no.1
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• pp.7-10
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• 1985

For each a.mem.S and f.mem.m(S), denote by $l_{a}$ f(s)=f(as) for all s.mem.S. If A is a norm closed left translation invariant subalgebra of m(S) (i.e. $l_{a}$ f.mem.A whenever f.mem.A and a.mem.S) containing 1, the constant ont function on S and .phi..mem. $A^{*}$, the dual of A, then .phi. is a mean on A if .phi.(f).geq.0 for f.geq.0 and .phi.(1) = 1, .phi. is multiplicative if .phi. (fg)=.phi.(f).phi.(g) for all f, g.mem.A; .phi. is left invariant if .phi.(1sf)=.phi.(f) for all s.mem.S and f.mem.A. It is well known that the set of multiplicative means on m(S) is precisely .betha.S, the Stone-Cech compactification of S[7]. A subalgebra of m(S) is (extremely) left amenable, denoted by (ELA)LA if it is nom closed, left translation invariant containing contants and has a multiplicative left invariant mean (LIM). A semigroup S is (ELA) LA, if m(S) is (ELA)LA. A subset E.contnd.S is left thick (T. Mitchell, [4]) if for any finite subser F.contnd.S, there exists s.mem.S such that $F_{s}$ .contnd.E or equivalently, the family { $s^{-1}$ E : s.mem.S} has finite intersection property.y.

• Research in Community and Public Health Nursing
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• v.27 no.1
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• pp.43-50
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• 2016

Purpose: The purpose of this study was to investigate the relationship of depression and smartphone dependency with female college students' career decision-making self efficacy. Methods: This was a descriptive study. The survey participants were 497 female college students in M City and S City. Data were collected from November 16 to December 4, 2015 using self-report questionnaires including BDI (Beck Depression Inventory), Smartphone Dependency Scale, and CDMSES-SF (Career Decision-Making Self Efficacy Scale-Short Form). Data were analyzed through descriptive statistics, independent-samples t-test, ANOVA, and stepwise multiple regression. Results: Career decision-making self efficacy showed significant differences according to religion. Smartphone dependency was found to have a statistically significant negative correlation with career decision-making self efficacy and a positive correlation with depression. Depression was found to have a statistically significant negative correlation with career decision-making self efficacy. Stepwise multiple regression analysis revealed that the predictors of career decision-making self efficacy were depression (7.1%), religion (1.8%), and smartphone dependency (1.3%), accounting for a total of 10.6% of the variance. Conclusion: This study suggests that interventions to promote female college students' career decision-making self efficacy should consider their depression, religion, and smartphone dependency.

• Journal of Korea Foundry Society
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• v.35 no.1
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• pp.8-14
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• 2015

Variations of nickel contents and microstructures in molten magnesium alloys on the addition of aluminum, zirconium, and manganese have been investigated. Specimens were prepared by melting under $SF_6$ and $CO_2$ atmosphere and casting into a disc of 29 mm diameter with 7~10 mm thickness from the melt acquired at the top of crucible. Before casting, the molten metal was stirred for 3 minutes after each addition of alloying elements and maintained for 30 minutes for settling down. Results showed that zirconium did not significantly affect the content of nickel while aluminum remarkably reduced it by forming $Al_3Ni_2$ phase. When manganese are added to Mg-1wt%Ni alloy along with aluminum, both elements remarkably reduced the content of nickel. The addition of 1.5 wt% manganese to Mg-1wt%Ni alloy containing aluminum further reduced the content of nickel by more than 30%, during which an additional intermetallic phase $Al_{10}Mn_3Ni$ was precipitated in the molten magnesium.

• Journal of Environmental Health Sciences
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• v.30 no.3
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• pp.283-292
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• 2004

Valid evaluation of community reaction to road-traffic noise exposure is important for the policy making and quality of life. The purpose of this study is to evaluate the relationship between community reaction and nighttime road-traffic noise. The study measured nighttime roadside noise caused by high traffic which is greater than LAeq(22:00-07:00) 65dB(A) and lower than 65dB(A) at Chonju city, from March to April, 2003. Three hundred sixty seven subjects, aged from 20 to 65, were selected from those who are residing close to the major roads. They were asked to answer the questions regarding noise source, stress(PWI-SF), annoyance, disturbance of specific activity, disturbance of sleep, somatic symptom, and four suggested confounding factors. The relationship between annoyance, somatic symptom and noise exposure was not significant. Adjusted odds ratio(95% C.I.) for disturbance of communication　 and disturbance of attention and rest　 were 1.59(1.03-2.71), 1.64(1.06-2.81), respectively. On the other hand sleep disturbance　 was indicated as 1.34(0.77-2.32). The results suggested that federal policy-making about road-traffic noise should consider community reaction evaluated by various perspective including annoyance, disturbance of specific activity, disturbance of sleep, and confounding factors.