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Numerical Signal Prediction and Calibration Using the Theory of a Current-Type Electromagnetic Flowmeter for Two-Phase Slug Flow (슬러그 2상유동에서 전류형식 전자기유량계 수치적 신호예측 및 보정)

  • Ahn Yeh-Chan;Oh Byung Do;Kim Jong-Rok;Kim Moo Hwan;Kang Deok-Hong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.29 no.6 s.237
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    • pp.671-686
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    • 2005
  • The transient nature and complex geometries of two-phase gas-liquid flows cause fundamental difficulties when measuring flow velocity using an electromagnetic flowmeter. Recently, a current-sensing flowmeter was introduced to obtain measurements with high temporal resolution (Ahn et al.). In this study, current-sensing flowmeter theory was applied to measure the fast velocity transients in slug flows. The velocity fields of axisymmetric gas-liquid slug flow in a vertical pipe were obtained using Volume-of-Fluid (VOF) method, and the virtual potential distributions for the electrodes of finite size were also computed using the finite volume method for simulating slug flow. The output signal prediction for slug flow was carried out from the velocity and virtual potential (or weight function) fields. The flowmeter was numerically calibrated to obtain the cross-sectional liquid mean velocity at an electrode plane from the predicted output signal. Two calibration parameters are proposed for this procedure: a flow pattern coefficient and a localization parameter. The flow pattern coefficient was defined by the ratio of the liquid resistance between the electrodes for two-phase flow with respect to that for single-phase flow, and the localization parameter was introduced to avoid errors in the flowmeter readings caused by liquid acceleration or deceleration around the electrodes. These parameters were also calculated from the computed velocity and virtual potential fields. The results can be used to obtain the liquid mean velocity from the slug flow signal measured by a current-sensing flowmeter.

Analysis of Individual Capability Factors to Improve Business Performance in the Environment of Technological Convergence (융합기술 환경에서 기업성과 향상을 위한 개인역량요인 분석)

  • Kang, Su-Hyun;Lee, Hong-Joo;Leem, Choon-Seong
    • The Journal of Society for e-Business Studies
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    • v.15 no.3
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    • pp.183-193
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    • 2010
  • Corporate business environment is rapidly evolving with the dramatic development of Information Technology. On that regard, companies are exploring various ways to create values in a bidto deliver outstanding business performance as well as coping with a changing business environment. Companies, in addition, have exerted extra efforts in developing and retaining talents as a way to enhance business performance. Against the backdrop, this paper presents a research-analysis model to analyze capability factors of corporate members which are essential for a company to create more values in the rapidly changing business environment. To this end, this paper carried out the following researches : First, through a literature review, capability types, which are required to improve business performance, as well as individual capability factors, were analyzed. Second, based on analysis result, Attitude, Skill and Knowledge were presented as individual capability factors essential to the technological convergence environment. Third, to analyze the validity of the research analysis model, expert interviews with corporate human resource as well as a large scale survey were performed.

Knowledge Distribution Status of the Korean SMC's Technology Commercialization Process Using a Knowledge Map (지식지도를 이용한 중소기업 기술사업화 프로세스의 지식 유통 현황 분석)

  • Yoo, Keedong
    • The Journal of Society for e-Business Studies
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    • v.23 no.2
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    • pp.67-81
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    • 2018
  • Technology commercialization is a reward process for companies' various trials and investment to develop technologies, which can be regarded as a way to figure out company's business performance. To successfully attain companies' purpose via technology commercialization, a variety of knowledge which triggers and completes business activities are needed. This paper suggests a methodology to analyze problems and solutions around the technology commercialization process in terms of knowledge distribution status, especially focused on Korean SMC cases. The knowledge map of this paper is constructed from the knowledge networks and identifies problems and solutions of the target process. A case study for applying proposed concepts to SMC's cases is also performed by checking knowledge distribution status and extracting practical implications. This paper's ideas can be regarded as one of references for SMCs to prepare technology commercialization with guaranteeing facilitated knowledge distribution and utilization.

A Statistical Modeling for the Economic Interpretation of Centrality in the International Arms Export (세계 무기 수출 중심성에 관한 통계적 분석과 경제적 의미)

  • Park, Joonsoo;Kim, Sung-Chul
    • The Journal of Society for e-Business Studies
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    • v.25 no.1
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    • pp.177-202
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    • 2020
  • We propose the statistical modeling and empirical results that can be utilized to identify and interpret the structural factors of international arms exports in recent years. The building blocks of research comprise the following questions; which would be the explanatory variables for the changing trend of international arms exports, whether the statistical significance can be verified on those variables and how those are interpreted for the future policy making purpose. We use the dataset of top 40 countries from SIPRI's Arms Transfers Database and analyze several regression models which consist of explanatory variables derived from research hypotheses. The most noticeable result is that the national fiscal reserve is shown to have consistent influence on the arms exports changes. UN security council members' group also has dominant power to make a formation of arms exports market block. Furthermore, gross domestic product and net exports volume in the national economy would seem to be related to changes of international arms exports in post-2000 period as well.

Improvement of Selective Consent Method in the Collection Process of Personal Information of Financial Institutions (금융기관의 개인정보 수집 절차 중 선택적 동의 방식의 개선방안)

  • Sun, Jong-chun;Kim, In-seok
    • The Journal of Society for e-Business Studies
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    • v.25 no.1
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    • pp.123-134
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    • 2020
  • Although the rights of data subjects are defined through laws such as the Personal Information Protection Act, the consent process for collecting personal information by financial institutions is only formal and does not guarantee the right of self-determination of personal information. Therefore, it is necessary to analyze the problem by information provision items of the current model, and to improve by changing the structure such as replacing the current method provided with the text with pictures and videos, and mandatory to provide the information subjects with personal information flow related images from the signing up stage. The improvement model is presented as a way to add a procedure to the current model. The effect was verified through a survey. It is hoped that the proposed model is actually reflected through the review to create an environment that can be a true meaning agreement that reflects the information subject's right to self-determination.

A Study on the Priority of 『Personal Information Safety Measure』 Using AHP Method: Focus on the Defferences between Financial Company and Consignee (AHP 기법을 이용한 금융회사 『개인정보의 안전성 확보조치 기준』 우선순위에 관한 연구: 금융회사 위·수탁자 간 인식 차이를 중심으로)

  • KIM, Seyoung;KIM, Inseok
    • The Journal of Society for e-Business Studies
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    • v.24 no.4
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    • pp.31-48
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    • 2019
  • To survive in the trend of the fourth industrial revolution, companies are putting a lot of attention and effort into personalization services using the latest technologies such as big data, artificial intelligence and the Internet of Things, while entrusting third parties to handle personal information on the grounds of work efficiency, expertise and cost reduction. In such an environment, consignors need to check trustees on a more effective and reasonable basis to ensure personal information safety for trustees. This study used AHP techniques to derive the importance and priority of each item of "Personal Information Safety Assurance Measures" for financial companies and trustees, and objectively compared and analyzed differences in perceptions of importance between financial institutions and trustees. Based on this, the company recognizes the difference between self-inspection of financial institutions and inspection of trustees and presents policy grounds and implications for applying differentiated inspection standards that reflect the weights appropriate for the purpose.

A Study on TCP Performance Enhancements in Wireless Networks (무선망에서의 TCP 성능 향상 방안에 관한 연구)

  • Park, Do-Yong;Kim, Young-Beom
    • Journal of IKEEE
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    • v.10 no.1 s.18
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    • pp.30-39
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    • 2006
  • The TCP protocol can provide some reliability using sliding window mechanism for data transmission, flow control, and congestion control. However, TCP has some limitations in that it has basically been designed solely for wired communication environments. If traditional TCP protocol is used also in wireless networks, the end-to-end data transmission performance degrades dramatically due to frequent packet losses caused by transmission errors and hand-offs. While there have been some research efforts on TCP enhancements considering the mobility of wireless communication devices, in this paper we propose a new method to improve the TCP performance by combining the Snoop and the Freeze-TCP methods. In the proposed scheme, the TCP end-to-end semantics is maintained and no changes of existing protocols in sending systems or in routers are required. It has the advantage of simple implementation because TCP code changes are limited to mobile devices for applying the Freeze-TCP and it requires only to add Snoop modules in base stations. Accordingly, the proposed scheme can operate well in the existing networks. Finally, in this study, we compared the performance of the proposed scheme with traditional TCP, other approaches through simulations using ns-2.

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Proposal of social commerce model for B2B (B2B 거래 기반의 소셜커머스 모델 소개)

  • Yoo, Soonduck;Kim, Jungihl
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.6
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    • pp.207-213
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    • 2012
  • With development of IT technology, B2C Social Commerce makes the change from closed type of transaction to the form of an open trading. Also by dramatically reducing the intermediate distribution and removing distribution costs, it provides goods at unbeatable prices to consumers. Depending on the flow of the times, the business-to-business struggles with the difficulty of PRM management and fast promotion of new products. Therefore, it is required B2B Social Commerce, new platform that can collect distribution and consumption firms in one place which is similar to B2C Social Commerce. Unlike the case of B2C social commerce, B2B Social Commerce should have an essential element, Installment payment system to pay over the period without purchase in accordance with the payment paid as a lump sum. B2B Social Commerce model which is introduced in this study will provide the solution of B2B transaction problems, opening up new markets and bring the expansion of the electronic market.

Use Case Development for Next Generation Electronic Nursing Record Systems Utilizing Clinical Workflow Analysis and a Delphi Survey (차세대 전자간호기록 시스템 유스케이스 개발: 업무흐름 분석과 전문가 델파이 기법 적용)

  • Cho, Insook;Choi, Woan Heui;Hyun, Misuk;Park, Yonok;Lee, Yoona;Lee, Sooyoun;Hwang, Okhee
    • Journal of Korean Clinical Nursing Research
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    • v.21 no.3
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    • pp.377-388
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    • 2015
  • Purpose: To identify user requirements for electronic nursing record (ENR) systems so as to ensure system usability. Methods: A mixed methods approach were applied in three steps : (i) task and workflow analysis with literature review of nursing documentation, (ii) literature reviews of system usability, and (iii) Use Case idenfication and consensus-based validation. We analyzed the nursing activity logs collected from a time-motion investigation of six hospitals. The Use Cases were validated by eight clinical experts from different hospitals and two experts from academia in a sequential Delphi survey. Consensus was achieved for the significance score and agreement among the panel. Results: Eight task groups and patterns of task flow were observed, which were translated into nine Use Cases. The specification of Use Cases was derived from principles, guidelines, and recommendations on nursing documentation and electronic health record systems, which was organized into three requirements of each Use Case: functionality, information, and design characteristics. Each Use Case achieved an agreement of 50~70%, and significance scores of 4 or 5 on a 5-point Likert scale. Conclusion: The nine Use Case identified were considered to be important and adequate in terms of both clinical and informatics contexts.

Design and Analysis of Digital Circuit System Considering Power Distribution Networks (파워 분배망을 고려한 디지털 회로 시스템의 설계와 분석)

  • Lee, Sang-Min;Moon, Gyu;Wee, Jae-Kyung
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.41 no.4
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    • pp.15-22
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    • 2004
  • This paper presents the channel analysis considering power distribution network(PDN) system of PCB. For achieve the target PDN system we proposed the useful design approach for acquiring the characteristic target of power distribution network in overall frequency ranges. The proposed method is based on the hierarchical approach related to frequency ranges and the path-based equivalent circuit model to consider the interference of the current paths between the decoupling capacitors and the board through it is a lumped model for fast and easy calculation, experimental results show that the proposed model is almost as precise as the numerical analysis. The analysis of PDN system shows that although the effective inductance of package dominatly affects the power noise and the signal transfer through data channel, the board PDNs also can not be neglected for achieving the accurate channel signaling. Therefore, we must design concurrently the chip, package, and board from the initial spec design of high speed digital system.