• 제목/요약/키워드: Energy contents

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플라이애시와 고로슬래그를 조합 사용한 초지연 콘크리트의 강도증진 (Estimation of the Strength Development of the Super Retarding Concrete Incorporating Fly Ash and Blast Furnace Slag)

  • 한민철
    • 한국건축시공학회지
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    • 제8권5호
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    • pp.119-125
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    • 2008
  • In this paper, the estimation of super retarding concrete incorporating mineral admixtures at the same time including fly ash(FA), blast furnace slag(BS) are studied based on maturity method. The setting time was retarded, as super retarding agent contents increase and curing temperature decreases. In addition, apparent activation energy by Arrhenius function was ranged from $24\sim35$ KJ/mol with slightly difference along with mixture proportion. This value is smaller than existing value $30\sim50$ KJ/mol. Based on strength development estimation. it exhibited comparable relativity between prediction value and measurement value. Therefore, this study provided effective strength development prediction value with super retarding agent contents and mineral admixture combination. Strength development prediction equation provided herein is possibly valid for estimating accurate strength development of the super retarding concrete at the job site.

블루투스 저전력 에너지 비콘을 이용한 근태관리 기반의 모바일 그룹웨어 시스템의 설계 및 구현 (Design and Implementation of a Mobile Group-ware System based on Absenteeism and Tardiness Management using Bluetooth Low Energy Beacon)

  • 권진관;송재오;홍승민;유재수
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2018년도 춘계 종합학술대회 논문집
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    • pp.501-502
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    • 2018
  • ICT기술은 소프트웨어와 하드웨어의 모든 분야에서 비약적으로 발전을 거듭하고 있다. 이에 따라, 기업에서 전통적으로 사용되어 오는 경영정보시스템들도 다양한 형태로 개선되거나 융합되어지고 있다. 특히, 재택근무, 이동근무, 원격 협업 등의 ICT기술 활용하여 시간과 장소에 얽매이지 않고 업무를 수행하는 스마트워크는 기업의 근무행태에 대한 패러다임을 바꿀 것으로 기대를 받고 있다. 본 논문에서는 이러한 스마트워크의 일환으로 BLE(Bluetooth Low Energy Beacon)을 이용한 모바일 형태의 그룹웨어 시스템을 제안한다.

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Surface Structure of Blend Films of Styrene/Acrylonitrile Copolymer and Poly(methyl methacrylate)(PMMA) or Hydrolyzed PMMA

  • 이원기;K. Tanaka;A. Takahara;T. Kajiyama;하창식
    • Bulletin of the Korean Chemical Society
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    • 제18권9호
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    • pp.958-961
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    • 1997
  • The compatibility and the surface structure of blends of poly(styrene-co-acrylonitrile) (SAN) with either poly(methyl methacrylate) (PMMA) or hydrolyzed PMMA (H-PMMA) were studied in terms of film thickness, interaction, and surface free energy difference on the basis of X-ray photoelectron spectroscopy (XPS), attenuated total reflection Fourier transform IR spectroscopy and atomic force microscopy. The XPS measurement showed that the surface enrichment of (PMMA/SAN) blends with different AN contents of SAN and with different carboxyl acid contents of PMMA was dependent on the molecular interaction, the surface free energy difference between components and the sample preparation history. It was found that the compatibility of H-PMMA and SAN was reduced with increasing carboxyl acid content of PMMA.

Study of Dark Matter at e+e- Collider using KISTI-5 Supercomputer

  • Park, Kihong;Cho, Kihyeon
    • International Journal of Contents
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    • 제17권3호
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    • pp.67-73
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    • 2021
  • Dark matter is barely known because it cannot be explained using the Standard Model. In addition, dark matter has not been detected yet. It is currently being explored through various ways. In this paper, we studied dark matter in an electron-positron collider using MadGraph5. The signal channel is e+e- → 𝜇+𝜇-A' where A' decays to dimuon. We studied the cross-section by increasing the center-of-mass energy. Central processing unit (CPU) time of simulation was compared with that using a local Linux machine and a KISTI-5 supercomputer (Knight Landing and Skylake). Furthermore, one or more cores were used for comparing CPU time among machines. Results of this study will enable the exploration of dark matter in electron-positron experiments. This study also serves as a reference for optimizing high-energy physics simulation toolkits.

전선피복용 고분자 컴파운드의 제조 및 물성 연구 (Study on Manufacture and Properties of Polymer Compounds for Cable Sheath)

  • 리시앙수;이상봉;조을룡
    • 반도체디스플레이기술학회지
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    • 제18권1호
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    • pp.42-47
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    • 2019
  • The four different polymer compounds were manufactured to make cable sheath for ship industry. Two kinds of ethylene-vinyl acetate (EVA) were selected as main matrix polymers for compounding with fire retardant, crosslinking agent, filler, plasticizer, and other additives. The properties of the four compounded materials were investigated with the contents of fire retardant, silane coated aluminum hydroxide (S-ATH). Rheology, Mooney viscosity, and tensile strength increased with S-ATH contents by reinforcing effect. With increasing fire retardant amount, fire resistance increased, but cold resistance didn't show an obvious enhancement due to polar effect of vinyl acetate in EVA.

Study on Property Change with a Fire Retardant Content in the Manufacture of Polymer Composites for Cable Sheath

  • Li, Xiang Xu;Lee, Sang Bong;Cho, Ur Ryong
    • Elastomers and Composites
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    • 제54권2호
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    • pp.118-122
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    • 2019
  • Four different polymer compounds were manufactured to make cable sheaths for the shipping industry. Two kinds of ethylene vinyl acetate (EVA) as the main matrix polymers and EVA-grafted maleic anhydride (EVA-g-MAH) as the coupling agent were selected for compounding with fire retardant, crosslinking agent, filler, plasticizer, and other additives. The properties of the four compounded materials were investigated with different contents of the fire retardant, silanecoated magnesium dihydroxide (S-MDH). In the rheology evaluation, the $t_{60}$ and ${\Delta}T$ values increased with increasing S-MDH contents. On the other hand, the tensile strength decreased with increasing S-MDH content due to a relative decrease in binder polymers. With increasing S-MDH content, fire resistance increased, but cold resistance showed no obvious enhancement due to the polar effect of vinyl acetate in EVA.

《典经》 所见风水文化论 (A Study of Feng-Shui Culture in The Canonical Scripture of Daesoon Jinrihoe)

  • 刘金成
    • 대순사상논총
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    • 제34집
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    • pp.263-292
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    • 2020
  • 大巡真理会广泛地吸收了诸多古老的传统文化, 形成独具特色的宗教文化, 而对风水文化的借鉴和改造就是其中的一个重要方面。在 《典经》 的记载中, 就有许多关于风水文化的内容。《典经》 中的风水文化, 既从传统的风水学说中汲取养分, 也进行了许多的创造性地理解。借助大巡真理会的教义对风水文化进行理解, 这就使得 《典经》 呈现出别具一格的特色。通过对 《典经》 中有关风水文化的整理, 本文试图从地气, 山势以及明堂这三个方面来讨论大巡真理会的风水文化。透过风水文化的视角对 《典经》 展开深入探究, 有助于更好地理解 《典经》 这一宗教圣典的深刻内容和神圣意义。

Changes in Biochemical Composition of the Digestive Gland of the Female Purple Shell, Rapana venosa, in Relation to the Ovarian Developmental Phases

  • Chung, Ee-Yung;Kim, Sung-Yeon;Park, Kwan-Ha
    • 한국패류학회지
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    • 제17권1호
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    • pp.27-33
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    • 2001
  • The Ovarian developmental phases of the reproductive cycle of Rapana venosa can be classified into five successive stages by histological study: early active stage (September to February), late active stage (December to April), ripe stage (March to July), partially spawned stage (May to August), and recovery stage (June to September). To understand the characteristics of nutrient storage and utilization in the digestive gland cells with ovarian developmental phases, we examined the digestive gland - which is the major nutrient supply organ associated with ovarian development of the female purple shell - by biochemical methods. Total protein contents in the digestive gland tissues increased in March (late active stage) and reached the maximum in May (ripe and partially spawned stages), and then their levels sharply decreased in July (partially spawned and recovery stages). Total lipid contents in the digestive gland tissues reached the maximum in January (early active stage). Thereafter, their levels rapidly decreased from May (ripe and partially spawned stages) and reached a minimum in July (partially spawned and recovery stages). The total DNA contents did not significantly change regardless of the different developmental stages of the ovary. However, it was also found from biochemical analysis that changes in total RNA content follow the same seasonal cycling to protein. These results indicate that the digestive gland is an important energy storage and supply organ in purple shells, and that the nutrient contents of the digestive gland change in response to gonadal energy needs.

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Determination of Nutritive Value of Citrus Tree Leaves for Sheep Using In vitro Gas Production Technique

  • Karabulut, Ali;Canbolat, Onder;Ozkan, Cagri O.;Kamalak, Adem
    • Asian-Australasian Journal of Animal Sciences
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    • 제20권4호
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    • pp.529-535
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    • 2007
  • The nutritive values of leaves of Citrus grandis, Citrus aurantium, Citrus oranges, Citrus limon, and Citrus deliciosa were evaluated by chemical composition and in vitro gas production techniques. There were significant (p<0.001) differences among citrus species in terms of chemical composition. Crude protein (CP) contents ranged from 123.0 to 148.3 g/kg DM. Neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents were varied with species in the range 219.4-355.4 and 215.0-278.8 g/kg DM respectively. Condensed tannin (CT) contents were ranged from 5.9 to 10.2 g/kg DM. The PEG addition significantly (p<0.001) increased the gas production and some estimated parameters of citrus tree leaves. However, species showed variable responses to polyethylene glycol (PEG) treatment. There were also significant (p<0.001) differences among species in terms of gas production and estimated parameters. The OMD and ME contents of citrus leaves without PEG supplementation were ranged from 66.5 to 73.3% and 9.8 to 10.9 MJ/kg DM respectively. The improvement in gas production, organic matter digestibility (OMD) and metabolizable energy (ME) with PEG emphasized the negative effect of tannins on digestibility. The increase (%) in the estimated OMD and ME contents ranged from 5.5 to 9.8% and 5.7 to 10.2% respectively. All citrus tree leaves studied in this experiment have potential nutritive values indicated by high crude protein content, OMD, ME and low fiber values.

지속가능경영을 위한 학교급식 영양사의 지식, 태도, 실천 가이드라인 콘텐츠 개발 (Development of the Contents of the Guideline for Dietitians' Knowledge, Attitudes and Practices (KAP) for Sustainable Management at School Foodservice)

  • 이나영
    • 한국식생활문화학회지
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    • 제32권6호
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    • pp.513-526
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    • 2017
  • The purpose of this study is to identify the guideline's contents for dietitians' knowledge, attitudes, and practices (KAP) for the sustainability management at school foodservice. The contents for the guideline were determined by the Delphi technique of two rounds. The Delphi panels of experts were consisted of sixteen school dietitians and fourteen professors of food and nutrition with more than 10 years of experiences by convenience sampling method. Based on the literature, knowledge, attitudes, and practices required for dieticians were classified into menu management, procurement, food production, facility and energy management, waste management, personnel management, and nutrition education. Data were analyzed using SPSS for Windows version 24 and EXCEL to calculate descriptive statistics, content validity ratio, degree of agreement, and degree of convergence. As a result of the second round, the validity scores of 'knows eco-friendly certification standards and labeling systems (4.53 point)' in the knowledge category, and 'tries to purchase local agricultural products (4.87 point)' in the attitude category were the highest. From that round in the practice category, the validity scores of 'plan menus for students' health', 'purchases eco-friendly food', and 'conserves energy in pre-processing and cooking process' were the highest with 4.73 point. Applying the criteria for securing the validity of the contents, the contents of 25 knowledge items, 20 attitude items and 30 practice items were confirmed. The findings of the study can be used to develop the guideline for dietitians required for the sustainability management.