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재하상태에 따른 탄소섬유보강공법의 휨 보강효과 (Flexural Rehabilitation Effect of Pre-loaded Reinforced Concrete Beams Strengthened by C.F.S)

  • 한복규;홍건호;신영수;조하나;정혜교
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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    • pp.691-696
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    • 1999
  • This paper is aimed to investigate flexural rehabilitation effect o pre-loaded reinforced concrete beams strengthened by carbon fiber sheet. Main Test parameters are reinforcement ratio and the magnitude of pro-loading and seven test beams are analyzed rehabilitation effect by carbon fiber sheet, load-deflection, failure mode, stress of reinforcing bar by the magnitude of pre-loading. Test results show that internal force was showed pre-loaded specimens lower than no-loaded specimens during rehabilitation and changing stiffness was showed in the same was and failure mode showed brittle failure from all specimens.

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A 6-Gb/s Differential Voltage Mode Driver with Independent Control of Output Impedance and Pre-Emphasis Level

  • Bae, Chang-Hyun;Choi, Dong-Ho;Ahn, Keun-Seon;Yoo, Changsik
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제13권5호
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    • pp.423-429
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    • 2013
  • A 6-Gb/s differential voltage mode driver is presented whose output impedance and pre-emphasis level can be controlled independently. The voltage mode driver consists of five binary-weighted slices each of which has four sub-drivers. The output impedance is controlled by the number of enabled slices while the pre-emphasis level is determined by how many sub-drivers in the enabled slices are driven by post-cursor input. A prototype transmitter with a voltage-mode driver implemented in a 65-nm CMOS logic process consumes 34.8-mW from a 1.2-V power supply and its pre-emphasized output signal shows 165-mVpp,diff and 0.56-UI eye opening at the end of a cable with 10-dB loss at 3-GHz.

Effect of Pre-shearing and Temperature on the Yield Stress of Stirred Yogurt

  • Yoon, Won Byong
    • 산업식품공학
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    • 제13권1호
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    • pp.70-73
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    • 2009
  • The yield stress of stirred yogurt was measured by the vane viscometer at different pre-shearing conditions, such as pre-shear speed, pre-shear time, and wait time, and temperature (12-38${^{\circ}C}$). The yield stress ranged from ~17.6 to 10 Pa and from 34.2 to 11.9 Pa, depending on the pre-shearing conditions and temperature, respectively. The preshear speed and the wait time significantly affected the yield stress. The temperature dependence of the yield stress was described by the Eyring's kinetic model. The linear function of the temperature on the yield stress was limited at the 22${^{\circ}C}$, and at the above 22${^{\circ}C}$, the yield stress was maintained to be a constant (~12.5 Pa).

면의 전처리 방법이 Rubia cordifolia 추출물의 염색성에 미치는 영향 (Influence of Cotton Pre-Treatment on Dyeing with Rubia cordifolia extracts for Cotton)

  • 이범훈
    • 한국염색가공학회지
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    • 제35권1호
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    • pp.1-7
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    • 2023
  • In this study, the influence of pre-treatment(bleaching, mercerization by liquid ammonia and caustic soda) on cotton fabrics were investigated on dyeing Rubia cordifolia extracts. Aluminium Sulfate, Iron(Ⅱ) Sulfate Heptahydrate, Copper(Ⅱ) Sulfate Pentahydrate, Tin(Ⅱ) Sulfate, Manganese(Ⅱ) Chloride Tetrahydrate were used as mordanting agents. K/S value and washing fastnesses of the dyed cotton fabrics pretreated under different conditions were investigated. The K/S values were increased in the order of bleaching, liquid ammonia and mercerization pre-treatment. It was found that the pre-treatment conditions did not significantly affect the color change. The colorfastness to washing of most of all dyed fabrics were over grade 4 regardless of pre-treatment condition.

Fashion and Periodic Conditions before and after World War I: - 1910s to the Beginning of 1930s -

  • Oh, Yun-Jeong;Cho, Kyu-Hwa
    • 패션비즈니스
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    • 제6권3호
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    • pp.60-68
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    • 2002
  • Fashion has been affected by the change of periodic conditions. A good example is found in the relationship between fashion and periodic conditions before and after World War I in the U.S. During the pre-wartime, the artificial silhouette achieved through using devices like the corset was popular and then women's dresses were very decorative and gorgeous using a wide variety of details. S-curved silhouettes and Paul Poiret's style will be reviewed as distinctive shapes of pre-war fashion in the beginning of the 20th Century. Through the war, women's rights improved enormously, the use of the automobile increased tremendously, and various kind of sports, the movie industry and ready-to-wear market developed very much. Women's clothes also changed to be much more practical and functional in post-war fashion. It seems that fashion is affected by the change of periodic conditions.

Genetic Variation and Correlation Studies of Some Carcass Traits in Goats

  • Das, S.;Husain, S.S.;Hoque, M.A.;Amin, M.R.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권7호
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    • pp.905-909
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    • 2001
  • Three groups of wethers viz. Jamunapari ♂$\times$Black Bengal ♀ (JBB), Selected Black Bengal ♂$\times$Selected Black Bengal ♀ (SBB) and Random Black Bengal ♂$\times$Random Black Bengal ♀ (RBB) of 1 year old were evaluated for pre-slaughter traits and carcass characteristics. The correlations between pre-slaughter traits and carcass traits were computed. It was found that the preslaughter weights of JBB and SBB were almost similar in yielding hot and chilled carcass as well as dressing percentage (DP). RBB wethers were lighter (p<0.05) than JBB and SBB in pre- and post-slaughter weights and also inferior (p<0.05) in DP. SBB wethers were found to produce more visceral fat compared to JBB and RBB. Other variety meats appeared erratic in yield.l. Correlations were compared by Z statistic among three genetic groups and the value of Z did not differ (p>0.05) between groups.

CareMyDog: Pet Dog Disease Information System with PFCM Inference for Pre-diagnosis by Caregiver

  • Kim, Kwang Baek;Song, Doo Heon;Park, Hyun Jun
    • Journal of information and communication convergence engineering
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    • 제19권1호
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    • pp.29-35
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    • 2021
  • While the population of pet dogs and pet-related markets are increasing, there is no convenient and reliable tool for pet health monitoring for pet owners/caregivers. In this paper, we propose a mobile platform-based pre-diagnosis system that pet owners can use for pre-diagnosis and obtaining information on coping strategies based on their observations of the pet dog's abnormal behavior. The proposed system constructs symptom-disease association databases for 100 frequently observed diseases under veterinarian guidance. Then, we apply the possibilistic fuzzy C-means algorithm to form the "probable disease" set and the "doubtable disease" set from the database. In the experiment, we found that the proposed system found almost all diseases correctly, with an average of 4.5 input symptoms and outputs 1.5 probable and one doubtable disease on average. The utility of this system is to alert the owner's attention to the pet dog's abnormal behavior and obtain an appropriate coping strategy before consult a veterinarian.

Effects of carbonation on hydration characteristics of ordinary Portland cement at pre-curing condition

  • Kim, Gwang Mok
    • 도시과학
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    • 제11권1호
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    • pp.21-28
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    • 2022
  • Raman spectroscopy is effective to investigate functional groups via molecular vibration. The technique offers the structural information of compounds including subtle changes in the chemical composition of local atomic coordination without critical damage. Thus, the effect of carbonation on the hydration characteristics of Portland cement under pre-curing conditions for carbonation was investigated via Raman spectroscopy in the present study. Gaseous CO2 was injected within 60 seconds, and the reaction time was varied from 0 minute to 90 minutes. The test results indicated that the Ca/Si ratio of C-S-H reduced immediately after mixing and then the C-S-H with a relatively high Ca/Si ratio coexisted as the reaction time increased. The calcium carbonates formed in the present study included calcite and amorphous calcium carbonates. The test results via Raman spectroscopy provide valuable information about the carbonation characteristics of OPC under pre-curing conditions for carbonation.

A Study of Pre-service Chemistry Teacher's Understanding on Entropy

  • Seo, Young-Jin;Hong, Hun-Gi
    • 한국과학교육학회지
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    • 제32권3호
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    • pp.415-427
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    • 2012
  • In this study, we conducted preliminary survey, diagnostic test and in-depth interview in order to study Korean pre-service chemistry teachers' understanding on entropy and investigate how Korean pre-service chemistry teachers deal with the natural phenomenon which is related to entropy conceptions. Firstly, as a result of the preliminary survey, it was found that pre-service chemistry teachers strongly recognized entropy as the degree of disorder. Secondly, the diagnostic test showed pre-service chemistry teachers were mostly confused about whether the entropy of the universe increases during a spontaneous change, and they had a tendency to interpret the natural phenomenon related to entropy change as the change of disorder. Finally, during in-depth interview, after we explained entropy change in all diagnostic test questions with the concept of microstate, pre-service chemistry teachers revealed a better understanding about entropy. Through this research, pre-service chemistry teachers had an opportunity to reflect on their deficiencies of entropy conceptions, which will ultimately help students to approach the concept of entropy more correctly.