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The Mediation Effect of Knowledge Transfer on IT Project Performance (IT 프로젝트 성과에 대한 지식이전의 매개효과에 관한 연구)

  • Lee, Sang-Hoon;Kim, Gi-Mun;Lee, Ho-Geun
    • Asia pacific journal of information systems
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    • v.15 no.3
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    • pp.9-39
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    • 2005
  • Recently, knowledge transfer has been recognized as one of the major factors for success of IT projects but little investigated in Information Systems research. IT project, which needs collaboration between organization's IT project team and external partner, is an critical source for a firm to acquire external knowledge and to achieve its competitive advantage. Based on this recognition on knowledge transfer under IT project, we investigate a mediation role of knowledge transfer to IT project performance after identifying its antecedents such as project team capabilities and partner capabilities. The research model is tested by analyzing 161 sample data gathered from firms' employees who have participated IT projects within last two years. The results reveal that knowledge transfer has full-mediation effect between its antecedents and IT project performance. Moreover, project team capabilities have more impacts on knowledge transfer than partner capabilities do.

Study on the Corrosionproofing in Concrete by Cathodic Protection (전위변화에 의한 콘크리트내의 철근방식에 관한 연구)

  • Lim, Seo-Hyung
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.3 no.2
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    • pp.213-220
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    • 1999
  • The purpose of this study is to apply cathodic protection to reinforced concrete structure and provide fundamental data to prevent the corrosion. The theory of cathodic protection of steel in concrete is to apply sufficient direct current so that corroding anodes on the steel are prevented from discharging ions. Two methods are used to supply the external current. In one, the protected metal is the cathode by connecting it to a more active metal. In the second, an external direct current power source supplies the current. The first is the sacrificial-anode system and the second the impressed-current system. The study results showed that the corrosion of the reinforcing steel in concrete could be enormously decreased by using protective current. The sacrificial anode and concrete nave to be adhered closely each in order to prevent the corrosion of reinforcing steel.

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Performance Characteristics Analysis of Gas Turbine-Pressurized SOFC Hybrid Systems (가스터빈-가압형 SOFC 하이브리드 시스템의 성능특성 해석)

  • 양원준;김동섭;김재환
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.7
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    • pp.615-622
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    • 2004
  • Recently, the hybrid system combining fuel cell and gas turbine has drawn much attention owing to its high efficiency and ultra low emission. It is now on the verge of world wide development and various system configurations have been proposed. A national project funded by Korean government has also been initiated to develop a pressurized hybrid system. This work aims at presenting design performance analysis for various possible system configurations as an initial step for the system development. Study focuses are given to major design options including the power ratio between gas turbine and fuel cell, reforming method (internal or external), reforming heat source (reforming burner, cathode hot air, fuel cell heat release) and steam supply method for reformer (anode gas recirculation, external steam generator). A wide variation in performance among different configurations has been predicted.

Implementation and Performance Evaluation of Safety Fence System Based on Industrial Fieldbus (산업용 필드버스 기반의 안전 펜스 시스템 개발 및 성능 평가)

  • Lee, Seung-Yong;Lim, Sun
    • IEMEK Journal of Embedded Systems and Applications
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    • v.14 no.1
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    • pp.43-49
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    • 2019
  • Recently, the importance of industrial fieldbus has been highlighted since the emergence of Industry 4.0. In particular, the Ethernet-based fieldbus protocol is actively used in automation systems. This paper proposes a safety fence system based on EtherCAT, a type of Ethernet-based fieldbus, to measure external loads. In order to measure the external loads, a force sensor was connected to an EtherCAT slave that transmits the sensor data to an EtherCAT master in real-time. The master ultimately controls the angle of the safety fence when it detects danger based on the given data. In the future, more effiecient safety fence system will be developed by using a HMI system to communicate with the EtherCAT master to manage safety and by employing multiple sensors to increase the accuracy of the fence system.

Theoretical Modeling of the Internal Power Flow and Absorption Loss of the Air Mode Based on the Proposed Poynting Vector Analysis in Top-emitting Organic Light-emitting Diodes

  • Kim, Jiyong;Kim, Jungho;Kim, Kyoung-Youm
    • Journal of the Korean Physical Society
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    • v.73 no.11
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    • pp.1663-1674
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    • 2018
  • We propose the Poynting vector analysis of the air mode in a top-emitting organic light-emitting diode (OLED) by combining the transfer matrix method and dipole source term. The spatial profiles of the time-averaged optical power flow of the air mode are calculated inside and outside the multilayer structure of the OLED with respect to the thickness of the semi-transparent top cathode and capping layer (CPL). We elucidate how the micro-cavity effect controlled by the thickness variation of the semi-transparent top cathode or CPL affects the internal optical power and absorption loss inside the OLED multilayer and the external optical power coupled into the air. When the calculated absorption loss and external power obtained by the proposed Poynting vector and currently-used point dipole models are compared, two calculation results are identical, which demonstrates the validity of the two models.

Location-Based Saliency Maps from a Fully Connected Layer using Multi-Shapes

  • Kim, Hoseung;Han, Seong-Soo;Jeong, Chang-Sung
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.1
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    • pp.166-179
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    • 2021
  • Recently, with the development of technology, computer vision research based on the human visual system has been actively conducted. Saliency maps have been used to highlight areas that are visually interesting within the image, but they can suffer from low performance due to external factors, such as an indistinct background or light source. In this study, existing color, brightness, and contrast feature maps are subjected to multiple shape and orientation filters and then connected to a fully connected layer to determine pixel intensities within the image based on location-based weights. The proposed method demonstrates better performance in separating the background from the area of interest in terms of color and brightness in the presence of external elements and noise. Location-based weight normalization is also effective in removing pixels with high intensity that are outside of the image or in non-interest regions. Our proposed method also demonstrates that multi-filter normalization can be processed faster using parallel processing.

On site monitoring during nearby drilling operations toward a geothermal power system installation

  • Bortoluzzi, Daniele;Casciati, Sara;Faravelli, Lucia;Francolini, Matteo
    • Smart Structures and Systems
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    • v.30 no.3
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    • pp.317-325
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    • 2022
  • Among the approaches to the production of "green" energy, geothermal power systems are becoming quite popular in Europe. Their installation in existing buildings requires an extended, external pipes appendix and its laying operation needs a drilling activities nearby structural skeletons often designed to support static loads only, especially when ancient buildings are targeted. This contribution reports and discusses the experimental results achieved within a specific case study within the European project GEOFIT. In particular, standard accelerometric measurements in and nearby a single-story reinforced concrete building are collected and analysed in the absence of drilling (pre-drilling) and during drilling activities (drilling phase) to monitor the structure response to the external source of vibrations related to the excavations phase. The target is to outline automatic guidelines toward installations preventing from any sort of structural damage.

A Study on the Radiation Source Effect to the Radiation Shielding Analysis for a Spent-Fuel Cask Design with Burnup-Credit (연소도이득효과를 적용한 사용후핵연료 수송용기의 방사선원별 차폐영향 분석)

  • Kim, Kyung-O;Kim, Soon-Young;Ko, Jae-Hoon;Lee, Gang-Ug;Kim, Tae-Man;Yoon, Jeong-Hyun
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.9 no.2
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    • pp.73-80
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    • 2011
  • The radiation shielding analysis for a Burnup-credit (BUC) cask designed under the management of Korea Radioactive Waste Management Corporation (KRMC) was performed to examine the contribution of each radiation source affecting dose rate distribution around the cask. Various radiation sources, which contain neutron and gamma-ray sources placed in active fuel region and the activation source, and imaginary nuclear fuel were all considered in the MCNP calculation model to realistically simulate the actual situations. It was found that the maximum external and surface dose rates of the spent fuel cask were satisfied with the domestic standards both in normal and accident conditions. In normal condition, the radiation dose rate distribution around the cask was mainly influenced by activation source ($^{60}Co$ radioisotope); in another case, the neutron emitted in active fuel region contributed about 90% to external dose rate at 1m distance from side surface of the cask. Besides, the contribution level of activation source was dramatically increased to the dose rates in top and bottom regions of the cask. From this study, it was recognized that the detailed investigation on the radiation sources should be performed conservatively and accurately in the process of radiation shielding analysis for a BUC cask.

Development for Improvement Methodology of Radiation Shielding Evaluation Efficiency about PWR SNF Interim Storage Facility (PWR 사용후핵연료 중간저장시설의 몬테칼로 차폐해석 방법에 대한 계산효율성 개선방안 연구)

  • Kim, Taeman;Seo, Myungwhan;Cho, Chunhyung;Cha, Gilyong;Kim, Soonyoung
    • Journal of Radiation Protection and Research
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    • v.40 no.2
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    • pp.92-100
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    • 2015
  • For the purpose of improving the efficiency of the radiation impact assessment of dry interim storage facilities for the spent nuclear fuel of pressurized water reactors (PWRs), radiation impact assessment was performed after the application of sensitivity assessment according to the radiation source term designation method, development of a 2-step calculation technique, and cooling time credit. The present study successively designated radiation source terms in accordance with the cask arrangement order in the shielding building, assessed sensitivity, which affects direct dose, and confirmed that the radiation dosage of the external walls of the shielding building was dominantly affected by the two columns closest to the internal walls. In addition, in the case in which shielding buildings were introduced into storage facilities, the present study established and assessed the 2-step calculation technique, which can reduce the immense computational analysis time. Consequently, results similar to those from existing calculations were derived in approximately half the analysis time. Finally, when radiation source terms were established by adding the storage period of the storage casks successively stored in the storage facilities and the cooling period of the spent nuclear fuel, the radiation dose of the external walls of the buildings was confirmed to be approximately 40% lower than the calculated values; the cooling period was established as being identical. The present study was conducted to improve the efficiency of the Monte Carlo shielding analysis method for radiation impact assessment of interim storage facilities. If reliability is improved through the assessment of more diverse cases, the results of the present study can be used for the design of storage facilities and the establishment of site boundary standards.

Denitrification Performance and Bacterial Community Structure of Methanol and Mixed Carbon Sources (메탄올과 혼합 외부탄소원의 탈질성능과 박테리아 군집 비교)

  • Suin Park;Junbeom Jeon;Minkyu Choi;Sungjin Kim;Sanghun Lee;Taeho Lee;Sanghyun Jeong;Hyokwan Bae
    • Journal of Korean Society on Water Environment
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    • v.39 no.1
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    • pp.61-75
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    • 2023
  • Denitrifying bacteria convert nitrate to nitrogen gas using an external carbon source as an electron donor. The external carbon source affects the denitrification performance and bacterial community structure. Although methanol is a cheap and effective external carbon source, the addition of diverse carbon sources may improve the total nitrogen removal rate and biomass characteristics, such as settleability. In this study, denitrifying reactions were performed using solely methanol and mixed carbon sources of methanol, glucose, and acetate in a sequencing batch reactor. The denitrifying reactor using methanol resulted in a total nitrogen removal rate of 0.39 ± 0.025 kg-N/m3-day while the suspended biomass transformed into dark brown granules. Methyloversatilis discipulorum had the highest predominance at 43.84%. The individual denitrifying biomasses, which were separately enriched with methanol, glucose, and acetate, showed the same total nitrogen removal performance of 0.39 ± 0.016 kg-N/m3-day. However, the addition of mixed carbon sources showed an improved total nitrogen removal rate of 0.42 ± 0.043 kg-N/m3-day, with the domination of Candidatus Saccaribacteria at 25.61%. The denitrifying granules turned pale yellow color. Influent COD/NO3--N ratios of 3.5, 5, and 7.5 exhibited COD/NO3--N consumptions of 4.3 ± 0.4, 4.4 ± 0.8, and 5.2 ± 0.7, and the consistent predominance of Candidatus Saccharibacteria.