• Title/Summary/Keyword: Open-gap

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Insertion of an Organic Hole Injection Layer for Inverted Organic Light-Emitting Devices

  • Park, Sun-Mi;Kim, Yun-Hak;Lee, Yeon-Jin;Kim, Jeong-Won
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.379-379
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    • 2010
  • Recent technical advances in OLEDs (organic light emitting devices) requires more and more the improvement in low operation voltage, long lifetime, and high luminance efficiency. Inverted top emission OLEDs (ITOLED) appeared to overcome these problems. This evolved to operate better luminance efficiency from conventional OLEDs. First, it has large open area so to be brighter than conventional OLEDs. Also easy integration is possible with Si-based driving circuits for active matrix OLED. But, a proper buffer layer for carrier injection is needed in order to get a good performance. The buffer layer protects underlying organic materials against destructive particles during the electrode deposition and improves their charge transport efficiency by reducing the charge injection barrier. Hexaazatriphenylene-hexacarbonitrile (HAT-CN), a discoid organic molecule, has been used successfully in tandem OLEDs due to its high workfunction more than 6.1 eV. And it has the lowest unoccupied molecular orbital (LUMO) level near to Fermi level. So it plays like a strong electron acceptor. In this experiment, we measured energy level alignment and hole current density on inverted OLED structures for hole injection. The normal film structure of Al/NPB/ITO showed bad characteristics while the HAT-CN insertion between Al and NPB greatly improved hole current density. The behavior can be explained by charge generation at the HAT-CN/NPB interface and gap state formation at Al/HAT-CN interface, respectively. This result indicates that a proper organic buffer layer can be successfully utilized to enhance hole injection efficiency even with low work function Al anode.

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A Legal Framework for Improving Patient Safety in Korea (환자안전 관련 법의 구조와 현황)

  • Ock, Minsu;Kim, Jang Han;Lee, Sang-il
    • Health Policy and Management
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    • v.25 no.3
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    • pp.174-184
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    • 2015
  • This paper reviewed structure and current status of laws related to patient safety using patient safety law matrix to promote systematic approach in legal system of patient safety. Laws related to patient safety can be divided into three areas: laws for preventing; laws for knowing about; and laws for responding. In the case of Korea, gaps are especially prominent in the areas of laws for knowing about and responding. Patient safety law which will be enacted in July 2016 will fill the gap in the area of laws for knowing about. This law will be comprehensive law, covering the full spectrum of laws related to patient safety. However, after reviewing current patient safety law in Korea, the following drawbacks were identified: absence of code for grasping the current patient safety level; absence of code for mandatory reporting in patient safety reporting system; and absence of code for privilege about patient safety work product. Furthermore we need wider discussions about covering issues of open disclosure, apology law, coroners system, and complaint management system in patient safety law.

A study on synthetic risk management on market risk of financial assets(focus on VaR model) (시장위험에 대한 금융자산의 종합적 위험관리(VaR모형 중심))

  • 김종권
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.22 no.49
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    • pp.43-57
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    • 1999
  • The recent trend is that risk management has more and more its importance. Neverthless, Korea's risk management is not developed. Even most banks does gap, duration in ALM for risk management, development and operation of VaR stressed at BIS have elementary level. In the case of Fallon and Pritsker, Marshall, gamma model is superior to delta model and Monte Carlo Simulation is improved at its result, as sample number is increased. And, nonparametric model is superior to parametric model. In the case of Korea's stock portfolio, VaR of Monte Carlo Simulation and Full Variance Covariance Model is less than that of Diagonal Model. The reason is that VaR of Full Variance Covariance Model is more precise than that of Diagonal Model. By the way, in the case of interest rate, result of monte carlo simulation is less than that of delta-gamma analysis on 95% confidence level. But, result of 99% is reversed. Therefore, result of which method is not dominated. It means two fact at forecast on volatility of stock and interest rate portfolio. First, in Delta-gamma method and Monte Carlo Simulation, assumption of distribution affects Value at Risk. Second, Value at Risk depends on test method. And, if option price is included, test results will have difference between the two. Therefore, If interest rate futures and option market is open, Korea's findings is supposed to like results of other advanced countries. And, every banks try to develop its internal model.

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Numerical simulation of propeller exciting force induced by milling-shape ice

  • Wang, C.;Li, X.;Chang, X.;Xiong, W.P.
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.11 no.1
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    • pp.294-306
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    • 2019
  • On the basis of the Computational Fluid Dynamics technique (CFD) combined with the overlap grid method, this paper establishes a numerical simulation method to study the problem of ice-propeller interaction in viscous flow and carries out a simulation forecast of the hydrodynamic performance of an ice-class propeller and flow characteristics when in the proximity of milling-shape ice (i.e., an ice block with a groove cut by a high-speed revolving propeller). We use a trimmed mesh in the entire calculation domain and use the overlap grid method to transfer information between the domains of propeller rotation calculation and ice-surface computing. The grid is refined in the narrow gap between the ice and propeller to ensure the accuracy of the flow field. Comparison with the results of the experiment reveals that the error of the hydrodynamic performance is within 5%. This confirms the feasibility of the calculation method. In this paper, we calculate the exciting force of the propeller, analyze the time domain of the exciting force, and obtain the curve of the frequency domain using a Fourier transform of the time-domain curve of the exciting force. The existence of milling-shape ice before the propeller can greatly disturb the wake flow field. Unlike in open water, the propeller bearing capacity shows a downward trend in three stages, and fluctuating pressure is more disordered near the ice.

Analysis on the Building System Integration Methods of the Salk Institute for Biological Studies (솔크 생물학 연구소에 적용된 건물시스템 통합기법 분석에 관한 연구)

  • Choi, Joon Sung
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.34 no.7
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    • pp.59-68
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    • 2018
  • Salk Institute for Biological studies is widely considered as architectural masterpiece of Louis Kahn's. Its iconic plaza with symmetrical concrete structures, overlooking the Pacific ocean in La Jolla, has been acclaimed as a facade to the sky. Little has been written on Kahn's achievements in the building system integration in order to bridge the gap between technology and design. This paper explores the technical issues, the design intents, and the major building systems to identify the Kahn's integration methods between building systems. The project is analysed into four major systems; structure, mechanical, envelope, and interior system. The integration methods of building systems are investigated in physical, visual, and functional aspects. The most distinguished cases of building system integration are the introduction of the interstitial floors between the laboratories and the creation of the smooth and warm materiality of exposed concrete walls. Kahn proposed open floor plans for the laboratories which are capable of easily adapting to changing needs. He also introduced the interstitial floors which are framed of the vierendeel truss systems and deliberately overlapped the structure systems with the mechanical systems such as ducts, water pipes, and electric conduits. The exposed concrete walls mixed with pozzolan ashes look very much like granite or limestone as the result of the physical and visual integration between structure, envelope, and interior systems.

Exploring Factors Affecting the Digitization of Blue Economy Micro- Small and Medium Enterprises (MSMEs): Indonesian Context

  • SIHOMBING, Sabrina O.;LAYMAN, Chrisanty V.;HANDOKO, Liza
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.10
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    • pp.129-135
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    • 2022
  • This study aims to identify the factors supporting and inhibiting the digitalization of blue economy MSMEs in Bitung, Indonesia. The literature shows little research on digitalization related to the blue economy in Southeast Asia, especially in Indonesia. This indicates that there is a large research gap related to digitalization and the blue economy in the Indonesian context. Data was collected through the distribution of questionnaires with open-ended questions to blue economy MSMEs. Data was also obtained from in-depth interviews with representatives of Aruna, an Indonesian company that focuses on simplifying the supply chain of fishery products by connecting small-scale fishers to the global market through technology. According to the study's findings, two primary factors-motivation to develop their business and efforts to maintain seller-buyer interaction-support SMEs' use of technology in the blue economy. However, digital literacy and technological infrastructure, such as the internet network, are the two main factors that become obstacles in the effort to digitize MSMEs in the blue economy. The role of the government is also a contingent factor that can strengthen the relationship between factors that support digitization and weaken the relationship between factors that hinder digitalization.

Coordinated Development of Agricultural Insurance, Agricultural Loans, and the Agricultural Industry in China

  • LI, Nan;JIA, Hong Da;KIM, Dong Joo
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.7
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    • pp.205-217
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    • 2022
  • The purpose of this study was to explore the relationship between agricultural insurance, agricultural loans, and the agricultural industry and find ways to consolidate and improve the interactive development between these three systems. We collected relevant data from 2009 to 2019 in 15 provinces of China and constructed a coupled coordination model to analyze the data. The results are as follows: First, the eastern part of China was ahead of the central and western parts in terms of agricultural loans and the agricultural industry, while the western part was ahead of the central and eastern parts in terms of agricultural insurance. Second, the coupling degree of the three systems in all 15 provinces reached an extremely high level. Third, all 15 provinces showed an overall continuous rise in coupling coordination degree. In 2019, eight provinces reached the medium-level coupling coordination development, and seven provinces were in a state of barely coupling coordination development. The three systems formed a mutually reinforcing relationship and basically entered a state of coordinated development. Finally, there was a great development gap between different regions of China concerning the coordinated development of the three systems, therefore, innovative development is urgently needed to further promote the coordinated development level.

Fine structure of the intercalated disc and cardiac junctions in the black widow spider Latrodectus mactans

  • Yan Sun;Seung-Min Lee;Bon-Jin Ku;Myung-Jin Moon
    • Applied Microscopy
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    • v.50
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    • pp.20.1-20.9
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    • 2020
  • Arthropods have an open circulatory system with a simple tubular heart, so it has been estimated that the contractile pumping structure of the cardiac muscle will be less efficient than that of vertebrates. Nevertheless, certain arthropods are known to have far superior properties and characteristics than vertebrates, so we investigated the fine structural features of intercalated discs and cardiac junctions of cardiac muscle cells in the black widow spider Latrodectus mactans. Characteristically, the spider cardiac muscle has typical striated features and represents a functional syncytium that supports multiple connections to adjacent cells by intercalated discs. Histologically, the boundary lamina of each sarcolemma connects to the basement membrane to form an elastic sheath, and the extracellular matrix allows the cells to be anchored to other tissues. Since the intercalated disc is also part of sarcolemma, it contains gap junctions for depolarization and desmosomes that keep the fibers together during cardiac muscle contraction. Furthermore, fascia adherens and macula adherens (desmosomes) were also identified as cell junctions in both sarcolemma and intercalated discs. To enable the coordinated heartbeat of the cardiac muscle, the muscle fibers have neuronal innervations by multiple axons from the motor ganglion.

Analysis of School Foodservice Managers' Job Satisfaction by Organizational Culture and Commitment in Jeju (제주지역 학교급식 관리자의 조직문화 및 조직몰입에 따른 직무만족도 분석)

  • Bu, Yun-Jeong;Chae, In-Sook
    • Journal of the Korean Society of Food Culture
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    • v.23 no.3
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    • pp.366-376
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    • 2008
  • The purpose of this study was to examine the job satisfaction of foodservice managers at schools in Jeju, Korea, according to the organizational culture and commitment of the school foodservice and administrative departments. The subjects included 144 (98.6%) dieticians from Jeju schools. The data were analyzed by descriptive analysis, reliability analysis, factor analysis, ttests, ANOVA, and Pearson's correlation coefficients, using the SPSS Win 12.0 program. In terms of organizational culture, the dieticians perceived the 'human relations model' and 'internal process model' as the strongest types for the school foodservice departments and administrative departments, respectively. However, for both types, a gap existed between the organizational culture that was perceived and that which was expected. In particular, the subjects expected that the 'human relations model' and 'open systems model' were the most important organizational culture types. In terms of the subjects' organizational commitment scores, loyalty and pride scored highest whereas unity scored lowest. For the level of job satisfaction, the performed work itself scored highest and was deemed most important. Additionally, organizational culture was positively correlated to the factors affecting organizational commitment and job satisfaction. Finally, the surveyed managers had high demands for a human relations-oriented organizational culture to enhance job satisfaction.

Updating BIM: Reflecting Thermographic Sensing in BIM-based Building Energy Analysis

  • Ham, Youngjib;Golparvar-Fard, Mani
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.532-536
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    • 2015
  • This paper presents an automated computer vision-based system to update BIM data by leveraging multi-modal visual data collected from existing buildings under inspection. Currently, visual inspections are conducted for building envelopes or mechanical systems, and auditors analyze energy-related contextual information to examine if their performance is maintained as expected by the design. By translating 3D surface thermal profiles into energy performance metrics such as actual R-values at point-level and by mapping such properties to the associated BIM elements using XML Document Object Model (DOM), the proposed method shortens the energy performance modeling gap between the architectural information in the as-designed BIM and the as-is building condition, which improve the reliability of building energy analysis. The experimental results on existing buildings show that (1) the point-level thermography-based thermal resistance measurement can be automatically matched with the associated BIM elements; and (2) their corresponding thermal properties are automatically updated in gbXML schema. This paper provides practitioners with insight to uncover the fundamentals of how multi-modal visual data can be used to improve the accuracy of building energy modeling for retrofit analysis. Open research challenges and lessons learned from real-world case studies are discussed in detail.

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