• Journal of Power Electronics
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• v.18 no.2
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• pp.456-466
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• 2018

This paper introduces the development of a de-icer based on a full-bridge modular multilevel converter (FMMC). The FMMC can generate a wide range of DC voltages owing to its modularity, scalability, and redundancy, which makes it suitable for ice-melting applications. First, operating principles and voltage ranges are analyzed when FMMC is applied as a mobile de-icer. Second, two new startup strategies, constant modulation index and constant power startup strategies, are proposed. Third, the main control strategies of the de-icer are proposed. Fourth, a novel rated-current zero-power test scheme is proposed to simplify test conditions. Finally, a 10 kV 1.5 kA mobile MMC de-icer is designed and built, and experiments are carried out to validate the proposed startup, control strategies, and rated-current zero-power test scheme.

• Proceedings of the Korean Society of Computer Information Conference
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• 2017.07a
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• pp.75-78
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• 2017

본 논문에서는 현재 다수의 게임 회사가 추구하는 수익 모델의 문제점을 조사하고 이로 인해 발생하는 부정적인 요인이 게임에 어떤 영향을 끼치는가를 분석하여 새로운 게임을 기획하거나, 운영할 때 과금정책에서 고려해야 할 점을 제시한다. 이러한 조사 및 분석은 앞으로 게임 운영자 및 게임 산업에 많은 도움이 될 것으로 기대된다.

• Management & Information Systems Review
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• v.4
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• pp.161-200
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• 2000

The results of this study on problems and activation plans of venture business are as follows. First, to ensure substantiality of venture business 1) To prepare and support venture investment capital. 2) To make eggective use of founding capital of venture business. 3) To establish the overall supporting system for founding of venture business. 4) To maintain and ensure manpower for venture business. Second. to prepare investment base for venture business 1) To induce the enlargement of venture investment unions. 2) To ensure the sound trust of KOSDAQ. 3) To permantly setup angel capital investment market. 4) To ensure joint system for R&D and knowledge management, and so forth. Third, to promote environment for the founding of venture business 1) To enlarge and roar business incubator (BI) 2) To establish acts of venture complex. 3) To uplift creative tension feeling and entrepreneurship. 4) To maximum the support for adminstration approvals, and so forth. Fourth, to make global strategy for venture business 1) To furnish oversea venture chances for globaligation to venture business. 2) To operate information network. 3) To establish integrating system of oversea support offices. Fifth, to support capital and tax 1) To activate functions of investment organs. 2) To increase the number of venture investment company. 3) To permanently organige angel capitalists. 4) To reduce and exampt the corporation tax, and the like. Above mentioned results of this study have to be practiced, and in future, subdivided studies will be needed.

• Korean Journal of Computational Design and Engineering
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• v.7 no.2
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• pp.110-120
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• 2002

This paper presents the method that allows easy and rapid integration of legacy resources within the company and between departments. The proposed system can easily construct a distributed environment for collaborative design between departments in the companies. It supports knowledge-based integration system, which allows designers to develop product with deep knowledge about product design. For the purpose, DOME (Distributed Object-based Modeling Environment)-which has been developed through various studies-was used in this paper. To overcome its problems and insufficiency, the Web-Integrator is proposed. The Web-Integrator is very suitable for an Internet environment because it uses HTTP (Hyper Text Transfer Protocol) and XML (extensible Markup Language) as its main communication method. By supporting the remote object access via URL (Uniform Resource Locator), the implementation of the integrated system makes the Web-Integrator systematic and intuitive. All the functions and resources provided by DOME could be used with the interface that enables bi-directional communication with the DOME system. Web-Integrator provides full web-based environments for the general designers, who do not have a full design knowledge and experience, and the proposed system allows design operations to happen at any place and anytime. Also it provides XML-RPC(Remote Procedure Call) based web service framework, which allows other systems to use easily the service that the DOME system supplies regardless the location and the platform.

• Journal of Drive and Control
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• v.15 no.4
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• pp.39-47
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• 2018

Recently, as environmental regulations for earth-moving equipment have been tightening, advanced systems such as electronic control, have been introduced for energy savings. An IMV (Independent Metering Valve) consisting of four 2-way valves, is an electro-hydraulic control systems that provides more flexible controllability, and potential for energy savings in excavators, when compared to the conventional 4-way spool valve system. To fully maximize use of an IMV, the bi-directional flow control valve that can regulate a large amount of flow in both directions, should be adopted. The hydraulic circuit of an IMV applied to an excavator from an overseas construction equipment company, reveals the flow control valve with the compound of proportional solenoid valve for first stage, and 2-way spool valve for the second stage. Moreover, the two spools are interconnected by a feedback spring, presumed to compensate for flow force acting on the second stage spool. This paper addresses the static analysis of flow control valve in an IMV to investigate the improvement of robustness, against flow force by the feedback spring. From the steady-state analysis of flow control valve model, it can be concluded that the feedback spring facilitates maintaining linearity of spool displacement for control input, and relatively constant flow for load disturbance.

• The Journal of Asian Finance, Economics and Business
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• v.10 no.2
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• pp.15-27
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• 2023

The purpose of this research is to investigate the impact of Business Intelligence (BI) on the relation between Big Data Analytics (BDA) and Financial Performance (FP), at the beginning we reviewed the academic accounting and finance literature to develop the theoretical framework of business intelligence, big data and financial performance in terms of definition, motivations and theories, then we conduct an empirical analysis based on questionnaire-base survey data collected. The researchers identified the study population in the joint-stock companies listed on the Egyptian Stock Exchange and operating in the sectors and activities related to modern technologies in information systems, big data analytics, and business intelligence, in addition to the auditing offices that review the financial reports of these companies, and The sector closest to the research objective is the communications, media, and information technology sector, where the survey list was distributed among the sample companies with (15) lists for each company, and (15) lists for each audit office, so that the total sample becomes (120) individuals (with a response rate 83.3%), The results show, First, Big data analytics significantly affect organizations' financial performance, second, Business intelligence mediates (partial) the relationship between big data analytics and financial performance.

• Steel and Composite Structures
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• v.49 no.3
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• pp.293-306
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• 2023

This article focuses on the study of the buckling behavior of two-dimensional functionally graded (2D-FG) nanosize tubes, including porosity, based on the first shear deformation and higher-order theory of the tube. The nano-scale tube is simulated using the nonlocal gradient strain theory, and the general equations and boundary conditions are derived using Hamilton's principle for the Zhang-Fu's tube model (as a higher-order theory) and Timoshenko beam theory. Finally, the derived equations are solved using a numerical method for both simply-supported and clamped boundary conditions. A parametric study is performed to investigate the effects of different parameters, such as axial and radial FG power indices, porosity parameter, and nonlocal gradient strain parameters, on the buckling behavior of the bi-dimensional functionally graded porous tube. Keywords: Nonlocal strain gradient theory; buckling; Zhang-Fu's tube model; Timoshenko theory; Two-dimensional functionally graded materials; Nanotubes; Higher-order theory.

• Journal of Digital Convergence
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• v.15 no.6
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• pp.121-132
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• 2017

In this study, there is a purpose of research to secure competitiveness through the effective utilization of intangible corporate resources of founded enterprises. For this research, we conducted a survey on the way the customers who used the products of the BI center and founders less than 7 years evaluated the founded company. Schmitt's empirical element was examined as a theoretical background, and it was examined whether these empirical factors and attitudes acted as a preprocess in the decision-making process as a repurchase intention. The Result of research is as follows. First, It clearly indicated that customer experience and search experience affected the degree of re-purchase. Second, customer's experience (use experience, search experience, contact experience) were grasped with significant influence on customer's attitude. Third, we discovered that customer's attitude had mediated between customer's experience (use experience, search experience) and re-purchase. This research suggests that if we manage empirical factors well, we can increase the degree of re-purchase and cope appropriately with the limitations of small and medium enterprises.

• Journal of Environmental Impact Assessment
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• v.4 no.1
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• pp.25-35
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• 1995

The objective of the study is to produce preferential impact assessment factors for Environmental Impact Assessment by considering regional features and public participation in the initial stages of EIA. In order to produce preferential impact assessment factors, the study was carried out through theoretical research and a survey of public awareness as a ways to reflect public participation based on theoretical research. The survey of public awareness was conducted in the form of an interview to review the impact which the construction of atomic power plants at Hyo-am village, Jang-an, Kyungsang Province and Bi-hak village, Suhsang-myon, Ulsan-Kun will have on the surrounding environment: to reflect public participation on deciding preferential assessment: and to determine the extent of alternatives of the proposed project. As the result of the study, the following were identified as preferential assessment factors in the settlement and surrounding areas cultivation marine products, change of temperature of seawater due to flow of warm water, land use(negative), noise vibration during construction, existing plants, erosion accumulation, influx of manpower for construction(negative), recreation landscaping during construction and operation, change in flow of transportation during construction, the quality of seawater during construction and operation were produced as preferential assessment factors in both settlement area and neighboring areas. In the settlement area, the educational environment(negative & positive) and positive aspects of the influx of manpower for construction were also identified as preferential assessment factors.

• Journal of Environmental Impact Assessment
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• v.4 no.3
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• pp.15-26
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• 1995

The objective of the study is to produce preferential impact assessment factors for Environmental Impact Assessment by considering regional features and public participation in the initial stages of EIA. In order to produce preferential impact assessment factor, the study was carried out through theoretical research and a survey of public awareness as way to reflect public participation based on theoretical research. The survey of public awareness was conducted in the form of an interview to review the impact which the construction of atomic power plants at Hyo-am village, Jang-an, Kyungsang Province and Bi-hak village, Suhsang-myon, Ulsan-Kun will have on the surrounding environment : to reflect public participation on deciding preferential assessment: and to determine the extent of alternatives of the proposed project. As the result of the study, the followings were identified as preferential assessment factors in the displacing settlement and surrounding areas: cultivation marine products, change of temperature of seawater due to flow of warm water, land use (negative), noise vibration during construction, existing vegetations, erosion sedimentation, influx of manpower for construction(negative), recreation landscaping during construction and operation, change in flow of transportation during construction, the quality of seawater during construction and operation were produced as preferential assessment factors in both displacing area and neighboring areas. In the displacing settlement area, the educational environment(negative & positive) and positive aspects of the influx of manpower for construction were also identified as preferential assessment factors.