• 천문학회보
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• 제38권2호
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• pp.56.1-56.1
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• 2013

Supernovae type Ia (SNe Ia) cosmology is providing the only direct evidence for the presence of dark energy. This result is based on the assumption that the look-back time evolution of SNe Ia luminosity, after light-curve shape correction, would be negligible. However, the most recent compilation of SNe Ia data shows systematic difference in the Hubble residual (HR) between the E and Sd/Irr galaxies, indicating that the light-curve fitters used by the SNe Ia community cannot quite correct for a large portion of the population age effect. In order to investigate this possibility more directly, we have obtained low-resolution spectra for 30 nearby early-type host galaxies. This data set is used to estimate the luminosity-weighted mean ages and metallicities of host galaxies by employing the population synthesis models. We found an interesting trend between the host galaxy age and HR, in the sense that younger galaxies have positive residuals (i.e., light-curve corrected SNe Ia luminosity is fainter). This result is rather independent of the choice of the population synthesis models employed. Taken at face value, this age (evolution) effect can mimic a large fraction of the HR used in the discovery of the dark energy. This result is significant at 1.4 - 3 sigma levels, depending on the light curve fitters adopted, and further observations and analyses are certainly required to confirm the trend reported here.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.1089-1092
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• 2008

철근과 콘크리트의 부착성능 확보는 철근콘크리트 구조물의 거동에서 중요한 요구사항이다. 구조체에 순환 잔골재 콘크리트를 적용하기 위해 순환 잔골재 콘크리트와 철근의 부착거동에 대한 규명이 매우 중요하다. 이에 따라 본 연구에서는 순환잔골재를 사용한 콘크리트와 철근 상호간의 부착거동을 평가하기 위하여 직접인발 실험을 수행하였다. 연구를 수행함에 있어 실험에 사용된 변수는 0, 100%의 순환잔골재 치환율 및 철근의 위치(상단근, 중간근, 하단근)로 하였다. 실험 결과는 CEB-FIP가 규정한 부착강도와 비교하였다. 본 연구를 통하여 얻어진 실험결과를 종합해 보면, 순환잔골재 콘크리트와 철근의 부착거동은 순환 잔골재 치환율 및 철근 위치에 영향을 받는다. H type 시험체의 경우 블리딩 현상이 일어나 V type 시험체와 HB 시험체만이 CEB-FIP가 규정한 부착강도를 만족하였다.

• 한국도서관정보학회지
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• 제53권1호
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• pp.211-230
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• 2022

이 연구는 대학생들의 독서태도와 독서율, 성격유형 간 영향 관계를 살펴보고, 이를 토대로 대학생의 독서율 향상 방안을 마련하고자 하였다. 연구 결과, 독서태도는 재미를 위한 독서량, 종이책 독서량, 개인 독서량, 전자책 독서량에 영향을 미치는 것으로 나타났으며, 성격유형에서 개방성은 독서량 및 독서태도에 긍정적인 영향을 미친 반면, 외향성은 독서량 및 독서태도에 전자책 독서량을 제외하고 부정적인 영향을 미치는 것으로 나타났다. 이를 통해 도출한 시사점은 다음과 같다. 첫째, 대학생들의 독서태도와 독서율 간의 높은 상관성을 기반으로 대학생이 재미있고 편안하게 책을 읽을 수 있는 도서관 환경 제공 및 자료의 비치가 필요하다. 둘째, 외향성은 독서량 및 독서태도에 부정적인 영향을 미치므로 독서량을 늘리기 위해서는 활동 중심으로 동적인 독서 활동을 진행하고 지역사회 활동과 연계한 교내 독서클럽 활동을 진행할 필요가 있다.

• 복식
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• 제52권6호
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• pp.51-69
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• 2002

The purpose of this study was to classify the body shapes. exclusive of size and corpulence factors of more than 60-year old elderly women by distinctions, and to investigate the visual effects of combination of ensemble suit details. For the body shape classification, the factor analysis and cluster analysis were performed : the mean value difference of numeral values for classified types were tested by ANOVA : and the follow-up test was conducted by the Duncan's multiple ranged test. The data analysis for visual effects evaluated by a multiple ranking test was analysed by mean. paired t-test, ANOVA and Duncan's multiple ranged test. The results are summarized as follows : 1. The followings are the types of body shape according to the shape factors of the front line of body for elderly women. The distinctions of the front li e of elderly women's body could be presumed; that was, Body typeⅠ was a comparatively well-balanced body type, Body type Ⅱ was close to an average body type. and Body type In was a severely corpulent body type. 2. The followings are the results on the physical visual effects inducing the constituents of clothing type. 1) The neckline·collar types of a jacket have a great influence on the visual effects of the upper body, and orderly. the tailored collar. soutien collar, and round neckline had positive influence on the visual effects in the upper body. 2) The pleat types of one-piece dress had positive influence on the visual effects in the lower body in the order of gored type, pleats type, and gathered type. Also. the balance in the lower body had more influence on the overall balance of the clothing compared to the constituents of clothing type such as neckline collar type or opening line. 3) It showed that whether there is the front opening line of a jacket influenced on the visual effects of all categories.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.24-27
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• 2001

Nowadays, increasing demand of the customized products has led to an increased usage of rapid prototyping in the product development. However, the acquisition price of a rapid prototyping equipment is still too high that not every body can afford to buy one. To offer a wide access to the users who need physical prototypes, a connection of the rapid prototyping equipment to the Internet is a viable step. It would allow a large group of customers all over the world to use the manufacturing capability of a service provider offering this kind of manufacturing service. To realize how such an e-manufacturing concept can look like, a LOM-type 3D printer developed at KIST has been used as test site and connected to the Internet. A possible user can log on to the server of the equipment and view his STL file and start the building operation from a remote place. To see whether the operation runs properly, a CCD camera is used to transmit the actual state of operation online. The result so far proves the feasibility of rapid prototyping on the Internet as well as an order-adaptive manufacturing system via web.

• 한국식품영양학회지
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• 제25권3호
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• pp.650-655
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• 2012

This purposes of this study were to explain consumer attitudes and purchasing behaviors towards agricultural products using a social network service and to determine the influencing factors such as experience, technology ability, innovation, self-efficacy, perception of usefulness, perception of trust, attitude, purpose of purchase and individual characteristics on them. We analyzed the survey data set, using the 'logit model', 'simultaneous equation model', and 'LISREL-Type model' In this study, the results obtained are summarized as follows. The result for the comprehensive statement of "Trust" was the biggest influence on the purchase agricultural products using the social network service. Therefore, in order to expand agricultural e-commerce using SNS, trust should be to the fore of marketing and publicity campaigns, in order to promote and stabilize the market.

• Wind and Structures
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• 제27권4호
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• pp.269-282
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• 2018

In this paper, a new displacement field based on quasi-3D hybrid-type higher order shear deformation theory is developed to analyze the static and dynamic response of exponential (E), power-law (P) and sigmoïd (S) functionally graded beams. Novelty of this theory is that involve just three unknowns with including stretching effect, as opposed to four or even greater numbers in other shear and normal deformation theories. It also accounts for a parabolic distribution of the transverse shear stresses across the thickness, and satisfies the zero traction boundary conditions at beams surfaces without introducing a shear correction factor. The beam governing equations and boundary conditions are determined by employing the Hamilton's principle. Navier-type analytical solutions of bending and free vibration analysis are provided for simply supported beams subjected to uniform distribution loads. The effect of the sigmoid, exponent and power-law volume fraction, the thickness stretching and the material length scale parameter on the deflection, stresses and natural frequencies are discussed in tabular and graphical forms. The obtained results are compared with previously published results to verify the performance of this theory. It was clearly shown that this theory is not only accurate and efficient but almost comparable to other higher order shear deformation theories that contain more number of unknowns.

• BMB Reports
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• 제40권5호
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• pp.773-782
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• 2007

Different isolates of the soil bacterium Bacillus thuringiensis produce multiple crystal (Cry) proteins toxic to a variety of insects, nematodes and protozoans. These insecticidal Cry toxins are known to be active against specific insect orders, being harmless to mammals, birds, amphibians, and reptiles. Due to these characteristics, genes encoding several Cry toxins have been engineered in order to be expressed by a variety of crop plants to control insectpests. The cotton boll weevil, Anthonomus grandis, and the fall armyworm, Spodoptera frugiperda, are the major economically devastating pests of cotton crop in Brazil, causing severe losses, mainly due to their endophytic habit, which results in damages to the cotton boll and floral bud structures. A cry1Ia-type gene, designated cry1Ia12, was isolated and cloned from the Bt S811 strain. Nucleotide sequencing of the cry1Ia12 gene revealed an open reading frame of 2160 bp, encoding a protein of 719 amino acid residues in length, with a predicted molecular mass of 81 kDa. The amino acid sequence of Cry1Ia12 is 99% identical to the known Cry1Ia proteins and differs from them only in one or two amino acid residues positioned along the three domains involved in the insecticidal activity of the toxin. The recombinant Cry1Ia12 protein, corresponding to the cry1Ia12 gene expressed in Escherichia coli cells, showed moderate toxicity towards first instar larvae of both cotton boll weevil and fall armyworm. The highest concentration of the recombinant Cry1Ia12 tested to achieve the maximum toxicities against cotton boll weevil larvae and fall armyworm larvae were 230 ${\mu}g/mL$ and 5 ${\mu}g/mL$, respectively. The herein demonstrated insecticidal activity of the recombinant Cry1Ia12 toxin against cotton boll weevil and fall armyworm larvae opens promising perspectives for the genetic engineering of cotton crop resistant to both these devastating pests in Brazil.

• 한국세라믹학회지
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• 제38권11호
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• pp.1023-1029
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• 2001

육방정 페라이트 $Co_2$Z(B $a_3$ $Co_2$F $e_{24}$ $O_{41}$ )를 여러 공침-산화 방법으로 제조하여 생성과정을 연구하였으며, 적절한 제조 방법을 결정하였다. 산화 및 공침 순서를 다르게 하여 $Ba^{2+}$, $Co^{2+}$, F $e^{2+}$ 등의 염화물 혼합 수용액으로부터 $Co_2$Z 조성의 수산화물을 제조하였다. 그리고 열처리 온도에 따른 생성상의 변화를 열분석(DTA/TGA), 분말 X-선 회절분석, 주사전자현미경 등을 이용하여 관찰하였다. $Co_2$Z 상은 출발물질이 비정질에 가까운 산수산화철($\delta$-FeOOH)일 경우에만 관찰되었으며, $Ba_3$F $e_{32}$ $O_{51}$ , BaF $e_{12}$ $O_{19}$ (M형), $Ba_2$ $Co_2$F $e_{12}$ $O_{22}$ (Y형)로부터 생성되었다. 염화물 혼합 수용액을 산화시킨 다음 침전하여 합성한 공침물은 110$0^{\circ}C$부터 $Co_2$Z가 생성되었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.85-88
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• 1998

Light-emitting diode(LEDs), diode arrays, and phosphor display panels are finding increased use in a variety of commercial applications. Present and anticipated application of these devices include solid state indicator(e.g., digital clocks, meter readout) and display systems(e.g., instrument panels, TV display), the application being determined by the light -output capability and size availability(cost) of the particular device. In this work, Phosphor based on ZnS:Cu are used. Relation by luminance with the thickness of insulating layer and phosphor layer are discussed. Increased thickness of insulating layer are stable on voltage to 300V. By considering thickness and voltage, optimal structure and thickness are investigated. Also in order to maximize even surface emission, various sieving process are introduced. Very similar phosphor particle size is selected. Luminance by various wave intensity is also investigated. 150cd/m$^2$ luminance are investigated in stable voltage and frequency.