• Title/Summary/Keyword: 열분석적 특성

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The Influence of Job Engagement on Customer-Orientation: Mediating Effect of Organization Trust (조직신뢰가 고객지향성에 미치는 영향 -직무열의의 매개영향을 중심으로-)

  • Hyun, Byung-Moo;Kim, Sung-Jong
    • The Journal of the Korea Contents Association
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    • v.15 no.4
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    • pp.443-453
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    • 2015
  • The purpose of this research is to investigate the influence of institution trust on customer-orientation of hotel practician. Comparison between two types of governance structure demonstrated that the relationship between institution trust and customer-orientation were significantly different each other. As hypothesized, influence of organization trust on customer-orientation was much stronger in privately owned organizations than that of public ownership organizations. In the test of mediating effect of job engagement between two variables were statistically significant Based on the results from SEM model, we can suggest that improvement of institution trust need to be emphasized through the rational introduction of customer-oriented system, establishing priority task system according to individual business criticality, admission and enhance of fault. Empirical evidences from structural equation model support the governance type positively influence the job attitude in service organizations.

Utilization of Fly Ash as a Source of Mineral Fertilizers -I. Mineralogical Characteristics (Fly ash 비료화(肥料化) 연구(硏究) -I. Fly ash의 광물학적(鑛物學的) 특성(特性))

  • Shin, Jae-Sung;Seong, Ki-Seog;Kim, Maun-Soo
    • Korean Journal of Soil Science and Fertilizer
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    • v.20 no.4
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    • pp.309-314
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    • 1987
  • This study was conducted to examine mineralogical aspects on anthractite and bituminous coal-fired power-plant ashes as a source of mineral fertilizer. Fly ashes contain dominant amounts of silica and alumina and considerable quantitites of potassium and boron. However, potassium and silica present in unavailable forms for plant growth. X-ray, DTA, and IR analysis of ash particles indicated the formation of new mineral, mullite with shape of which were spherical in the surface morphologies of SEM. Detailed SEM investigation showed the presence of imbedded blocky shape silicate material.

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A Study of Drought and Climate Change Effect Based on Copula (코풀라 기반의 가뭄분석 및 기후변화 영향)

  • Kwak, Jae-Won;Kim, Duck-Gil;Noh, Hee-Seong;Kim, Hung-Soo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2012.05a
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    • pp.392-392
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    • 2012
  • 기후변화로 인해 가뭄 재해는 수자원 관리 및 계획에 큰 부담으로 작용하므로 이에 대한 연구와 대책 마련이 필요하나, 아직까지 가뭄 특성의 정량적인 거동 분석이나 기후변화가 가뭄에 미치는 영향 연구는 아직 미흡하다. 이에 본 논문에서는 가뭄변수 분석을 통해 결합확률을 이용한 가뭄분석이 타당함을 보이고, 코풀라 이론에 의해 결합확률을 이용한 가뭄빈도분석을 수행하고자 하였다. 또한 기후변화가 유역단위의 수문학적인 가뭄에 미치는 영향을 정량적으로 평가하고 예측하고자 하였다. 이를 위하여 가뭄 사상에 대하여 전통적인 방법으로의 빈도분석을 수행하였다. 이를 Clayton 코풀라 함수를 적용하여 가뭄의 결합확률을 고려한 빈도분석을 수행해 기존의 단변량 기반의 빈도분석 방법과 비교 분석 하였다. 또한, 결합확률을 이용하여 가뭄의 재현빈도를 분석하고 이를 이용하여 가뭄의 심도-지속기간-빈도 곡선을 유도하였다. 그리고 기후변화가 가뭄에 미치는 영향을 분석하기 위하여 IPCC의 SRES A1B 시나리오와 KMA RCM 기후모형을 이용하여 미래 가뭄 시계열을 산정하고, 미래 가뭄에 대한 결합확률 빈도해석과 미래 가뭄분석을 수행하였다. 본 연구의 결과에 따르면 가까운 미래에 짧은 지속기간을 가진 심한 가뭄이 다발할 것으로 전망되었다.

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Analysis of Fire Characteristics based on the Thickness and Incident Heat Flux of Wood (합판류 목재의 두께별 입사열유속에 따른 연소특성 비교 연구)

  • Hwang, Sun-Woo;Park, Won-Hee;Kim, Chang-Yong
    • Fire Science and Engineering
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    • v.34 no.4
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    • pp.13-21
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    • 2020
  • This study tested the wood used in building interiors; each type had various incident heat fluxes based on their thickness. The combustion characteristics measured were effective heat of combustion, heat release rate peak and arrival time, maximum average rate of heat emission, and piloted ignition temperature. The wood specimens used in the experiment were 4.8 to 18 mm thick. 25, 35, 50, and 60 kW/㎡ were applied to the incident heat flux that the wood specimens were exposed to. The wood specimens tested were two types of medium-density fiberboard (each with a different density), treated red pine, particle board, and plywood. A comprehensive comparison of different fire characteristics was conducted to analyze the fire patterns corresponding to each type of wood in this way, the risk of fire was studied. The risk of fire was particularly high for particle board. The results of quantifying the fire characteristics of the types of wood studied could function as important input data with which to calculate the fire load of composite combustibles.

Thermoluminescence of Rb2LiCeCl6 Halide Scintillator (Rb2LiCeCl6 할라이드 섬광체의 열형광 특성)

  • Kim, Sunghwan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.2
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    • pp.1211-1215
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    • 2014
  • We developed a new $Rb_2LiCeCl_6$ scintillator and determined the scintillation and thermoluminescence properties of the scintillator. The emission spectrum of $Rb_2LiCeCl$ is located in the range of 350 ~ 410 nm, peaking at 368 nm and 378 nm, due to the 4f ${\rightarrow}$ 5d transition of $Ce^{3+}$ ions. The fluorescence decay time of the crystal is composed two components. The fast component is 71 ns (85%) and the slow component is 405 ns (15%) of the crystal. The after-glow is caused by the electron and hole traps in the crystal lattice. We determined physical parameters of the traps in the crystal. The determined activation energy(E), kinetic order(m) and frequency factor(s) of the trap are 0.75 eV, 1.48 and $3.0{\times}10^8s^{-1}$, respectively.

Analysis of Nocturnal Cold Air Flow Characteristics for Setting of Tropical Night Response Zone in Daegu (대구시 열대야 대응 구역 설정을 위한 야간 찬공기 유동성 분석)

  • SEO, Bo-Yong;LEE, Sang-Beom;GWON, Soon-Beom;CHA, Jae-Gyu;JUNG, Eung-Ho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.23 no.3
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    • pp.220-235
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    • 2020
  • Heat wave generation in cities is basically affected by global warming, but it is further exacerbated by the impact of artificial heat emission and heat accumulation in the city. In particular, the effects of urban heat waves directly affect the occurrence of tropical nights. Basically, however, the choice of countermeasures against tropical nights is very limited compared to the daytime heat wave response. The purpose of this study was to analyze the characteristics of cold air flow at night as a countermeasure against tropical nights in Daegu Metropolitan City and to suggest its spatial applicability. As a research method, the spatial characteristics (flow velocity, flow rate, flow direction and range) of cold air flow in Daegu were quantitatively analyzed using KLAM_21, a cold air flow analysis program. As a result of the analysis, it was found that cold air generation and flow in the surrounding mountains of Daegu Metropolitan City was very active, but the inflow was limited to the urban area, which has tropical nights. However, it has been shown that the flow of cold air flowing from the surrounding mountains is very active in some urban areas, so it has spatial conditions that are very effective in countering tropical nights. If these spatial conditions are used for the urban planning, it will be very useful to develop countermeasures for tropical nights.

Comparative Analysis of Wind Flows in Wind Corridor Based on Spatial and Geomorphological Characteristics to Improve Urban Thermal Environments (도시 열환경개선을 위한 공간지형적 특성에 따른 바람길 유동 비교 분석)

  • SEO, Bo-Yong;JUNG, Eung-Ho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.20 no.2
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    • pp.75-88
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    • 2017
  • This study analyzed wind flows based on spatial and geomorphological characteristics of Daegu Metropolitan City. A three-stage analysis was performed, starting with a comparison of meteorological relationships between local wind direction (synoptic wind) and local wind flow. In the second stage the study area was subdivided into districts and suburban districts to analyze the relative change of local wind flow. In stage three, the formation of wind corridor for local wind flow, wind flow for the entire urban space, and spatial relationships between flows were verified comparatively using KLAM_21. Three results are notable, the first of which is a low correlation between synoptic wind of a region, and local wind, flow in terms of meteorology. Secondly, observations of local wind flow at five downtown districts and two suburban districts showed that there were diverse wind directions at each measurement point. This indicates that the spatial and geomorphological characteristics of areas neighboring the measurement points could affect the local wind flow. Thirdly, verifying the results analyzed using KLAM_21, compared to Atomatic Weather System(AWS) measurement data, confirmed the reliability of the numerical modelling analysis. It was determined that local wind flow in a city performs a spatial function and role in ameliorating the urban heat island phenomena. This indicates that, when an urban planning project is designed, the urban heat island phenomena could be ameliorated effectively and sustainably if local wind flow caused by immediate spatial and geomorphological characteristics is confirmed systematically and techniques are intentionally applied to connect the flows spatially within areas where urban heat islands occur.

An Empirical Study on Web-based Question-Answer Services (지식검색서비스 이용에 관한 실증적 연구)

  • Park, Joo-Bum;Jeong, Dong-Youl
    • Journal of the Korean Society for information Management
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    • v.21 no.3
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    • pp.83-98
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    • 2004
  • The purpose of this study is to review the characteristics of a web-based question-answer service and to analyze the information needs and use behavior of the service for a more efficient question-answer service plan. On the basis of the findings, this study makes suggestions for the question-answer service in respect of reinforcing the effectiveness of information itself and the efficiency of question-answer services. The speciality. accuracy. and specificity including the variety of themes should be improved for more effective information. Also. interactivity. readiness. and convenience should be improved for a more efficient service.

Preparation and Characteristics of Cellulose Acetate Based Nanocomposites Reinforced with Cellulose Nanocrystals (CNCs) (셀룰로오스 나노크리스탈 강화 셀룰로오스 아세테이트 나노복합소재 제조 및 특성)

  • Gwon, Jae-Gyoung;Lee, Dan-Bee;Cho, Hye-Jung;Lee, Sun-Young
    • Journal of the Korean Wood Science and Technology
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    • v.46 no.5
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    • pp.565-576
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    • 2018
  • Cellulose acetate (CA) has been widely utilized for composite materials due to its high transparency and thermal resistance. In this study, CNCs (cellulose nanocrystals) were reinforced in CA nanocomposites for fortifying mechanical properties of the composites. In addition, CA nanocomposites reinforced with CNCs were manufactured by extrusion/injection processes applied with CNC-predispersion method for achieving a high dispersion level of CNCs in the CA matrix. According to the analysis of mechanical properties, the CA nanocomposite with 3 wt% CNCs has the highest tensile and flexural strengths due to the reinforcing effect of CNC nanoparticles. Thermogravimetric analysis (TGA) showed that the addition of acid hydrolyzed CNCs slightly lowered the initial pyrolysis temperature of CA nanocomposite.

Preparation and Physical Properties of Eco-Friendly Biodegradable PLA/PBAT/HCO Blended Films (친환경 생분해성 PLA/PBAT/HCO 블랜드 필름 제조 및 물리적 특성)

  • Lee, Seung-Min;Kim, Han-Seong;Yun, Yeon-Hum;Hyung, Tae-Gyung;Yoon, Soon-Do
    • Applied Chemistry for Engineering
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    • v.31 no.4
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    • pp.416-422
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    • 2020
  • In this study, eco-friendly biodegradable materials were prepared using poly(lactic acid) (PLA), poly(butylene adipate-co-terephthalate) (PBAT), and hydrogenated castor oil power (HCO) as an additive. The prepared PLA/PBAT/HCO blended films were characterized by the scanning electron microscope (SEM) and fourier-transform infrared spectroscopy (FT-IR). The results of SEM analysis indicated that PLA/PBAT (8 : 2) blended films added HCO showed no rough area, crack, or large agglomeration when compared with those adding various additives (12-hydroxy stearic acid (12HSA) and cellulose). The FT-IR results indicated the presence of specific peak of HCO in the PLA/PBAT blended films, and its peak intensity increased with increasing HCO content (0~5.0 wt%). Tensile strength, elongation at break, and water barrier and thermal properties of the prepared PLA/PBAT/HCO blended films were also investigated, indicating that the physical and thermal properties was improved more than three times by the addition of HCO. The biodegradability test in soil revealed that the prepared biodegradable materials were degraded by about 6.0~20% after 90 days.