• 제목/요약/키워드: Technical Errors

검색결과 246건 처리시간 0.022초

Self-Modeling Curve Resolution Analysis of On-line Near Infrared Spectra Measured during the Melt-Extrusion Transesterification of Ethylene/Vinylacetate Copolymer

  • Sasic, Slobodan;Kita, Yasuo;Furukawa, Tsuyoshi;Watari, Masahiro;Siesler, Heinz W.;Ozaki, Yukihiro
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1284-1284
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    • 2001
  • The transesterification of molten ethylene/vinylacetate (EVA) copolymers by octanol as a reagent and sodium methoxide as a catalyst in an extruder has been monitored by on-line near infrared (NIR) spectroscopy. A total of 60 NIR spectra were acquired for 37 minutes with the last spectrum recorded 31 minutes after the addition of octanol and catalyst was stopped. The experimental spectra show strong baseline fluctuations which are corrected for by multiplicative scatter correction (MSC). The chemometric methods of orthogonal projection approach (OPA) and multivariate curve resolution (MCR) were used to resolve the spectra and to derive concentration profiles of the species. The detailed analysis reveals the absence of completely pure variables that leads to small errors in the calculation of pure spectra. The initial estimation of a concentration that is necessary as an input parameter for MCR also presents a non-trivial task. We obtained results that were not ideal but applicable for practical concentration control. They enable a fast monitoring of the process in real-time and resolve the spectra of the EVA copolymer and the ethylene/vinyl alcohol (EVAL) copolymer to be very close to the reference spectra. The chemometric methods used and the decomposed spectra are discussed in detail.

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전자무역 기반사업의 구현에 관한 연구 (A Study on the Realization of Infrastructure for Electronic Trade)

  • 이봉수
    • 통상정보연구
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    • 제12권1호
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    • pp.55-73
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    • 2010
  • The thesis examines new innovation of various aspect to overcome lots of problems which come by when we execute simplification of trade procedure and administration fairly. Practical implications regarding the innovation of electronic trade infrastructure are as follows. First, it will propel the standardization of electronic trade section in the technical side and the construction atmosphere of international authentication system must be created. The work process should be redesigned in order to implement export-import procedures that meet the relevant standards. Second, the improvement of system for electronic process is necessary in the law and institutional aspect. In order to eliminate any obstacles to the trade procedure, clearer legal grounds regarding legitimate controls and minimum necessity must be established. Also, laws should be revised to admit mutual recognition among certification organizations, in lieu of international agreement-based mutual recognition between government. Third, the detailed improvement for the integration of the electronic trade infrastructure will be demanded. Additionally, user-centered quality management protocols should be established via connections with the systems already existing in governmental bodies. Fourth, various trade institution should harmonized and interconnected with other partners through mutual cooperation for standardization of operational system. A system which can monitor and remotely diagnose and resolve system errors should be established to provide tailor-made service and improve operational efficiency. At the same time, it is necessary to build a cooperative system to share information and promote comprehensive management for efficient operation.

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제주월드컵경기장 지붕구조물의 시공 (Construction of Roof Structure for Jeju Worldcup Stadium)

  • 이주영;김찬수
    • 한국건설관리학회:학술대회논문집
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    • 한국건설관리학회 2002년도 학술대회지
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    • pp.174-179
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    • 2002
  • 케이블로 지지되는 제주월드컵경기장의 지붕구조물이 구조적으로 안정한 거동을 하기 위해서는 케이블의 시공시 구조설계자가 요구하는 정확한 초기장력을 케이블에 부여해야 한다. 본 연구에서는 케이블의 시공을 위하여 장력도입 절차와 절차에 따른 장력의 계산을 기하학적 비선형을 고려한 유한요소해석을 통하여 수행하여 그 유효성을 평가하고 적용하였다. 지붕구조물을 지지하는 케이블에 장력을 도입하는 작업은 정확한 장력의 계산뿐 아니라, 각 작업을 진행 중 구조적으로 안정성을 확보해야 하며, 작업공정을 최소로 줄이고 후속공정에 영향을 미치는 요인을 분석하여 최소한 공기와 효율적인 장비의 운용되도록 계획하여야 한다. 본 연구에서는 현장의 여건과 기술적 오류를 보완하기 위한 작업 절차의 변경 등을 고려하여 제주월드컵경기장의 지지케이블의 장력을 허용오차범위내에서 조정할 수 있었다.

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선박의 안전평가에서 교육적, 문화적 영향인자에 대하여 (On the Educational and Cultural Aspects in the Ship Safety Assessments)

  • 권영섭;김남휘
    • 해양환경안전학회지
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    • 제10권2호
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    • pp.23-27
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    • 2004
  • 1970년대의 해기사들의 선박의 안전에 대한 비판과 연구에서 문제를 제기한 후, 오늘날 국제해사기구(IMO)를 비롯하여 선박안전 평가 방법의 개발과 소개가 활발히 이루어지고 있다. 선박안전의 상당부분이 인적과실에 기인하여 이에 대한 고려 요구가 높아지고 있다. 본 연구에서는 선박안전평가 방법의 개요를 살피고 인적과실의 구조 인식을 통한 문화적, 교육적 영향인자에 대해 고찰함으로써 선박안전성 제고에 기여하고자 한다.

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Framework for assessing responsiveness to personal data breaches based on Capture-the-Flag

  • Oh, Sangik;Kim, Byung-Gyu;Park, Namje
    • Journal of Multimedia Information System
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    • 제7권3호
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    • pp.215-220
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    • 2020
  • Many state agencies and companies collect personal data for the purpose of providing public services and marketing activities and use it for the benefit and results of the organization. In order to prevent the spread of COVID-19 recently, personal data is being collected to understand the movements of individuals. However, due to the lack of technical and administrative measures and internal controls on collected personal information, errors and leakage of personal data have become a major social issue, and the government is aware of the importance of personal data and is promoting the protection of personal information. However, theory-based training and document-based intrusion prevention training are not effective in improving the capabilities of the privacy officer. This study analyzes the processing steps and types of accidents of personal data managed by the organization and describes measures against personal data leakage and misuse in advance. In particular, using Capture the Flag (CTF) scenarios, an evaluation platform design is proposed to respond to personal data breaches. This design was proposed as a troubleshooting method to apply ISMS-P and ISO29151 indicators to reflect the factors and solutions to personal data operational defects and to make objective measurements.

Three-dimensional finite element analysis of reinforced concrete slabs strengthened with epoxy-bonded steel plates

  • Metwally, Ibrahim M.
    • Advances in concrete construction
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    • 제2권2호
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    • pp.91-108
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    • 2014
  • This paper presents a nonlinear finite element analysis (FEA) in order to investigate the flexural performance of one-way slabs strengthened by epoxy-bonded steel plates. Four point loading scheme is selectively chosen. A model is developed to implement the material constitutive relationships and non-linearity. Five Slabs were modeled in FEM software using ABAQUS. One slab was unstrengthened control slab and the others were strengthened with steel plates with varying the plate thickness and configuration. In order to verify the accuracy of the numerical model, a comparison was done between the experimental results available in the literature and the proposed equations by ACI 318-11 for the calculation of ultimate load capacities of strengthened slabs, the agreement has proven to be good and FEA attained accurate results compared with ACI code. A parametric study was also carried out to investigate the influence of thickness of steel plate, strength of epoxy layer and type of strengthening plate on the performance of plated slabs. Also, the practical and technical feasibility of splitting the steel plate in strengthening process has been taken into account. For practical use, the author recommended to use bonded steel plate as one unit rather than splitting it to parts, because this saves more effort and reduces the risk of execution errors as in the case of multiple bonded parts. Both techniques have nearly the same effect upon the performance of strengthened slabs.

Impacts of Foreign Direct Investment on Human Capital in ASEAN

  • NGUYEN, Hoi Van;NGUYEN, Thuy Thi Thu;TO, Tha Hien;DANG, Duong Quy;Luong, Trang Thi Dai
    • 유통과학연구
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    • 제18권9호
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    • pp.13-18
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    • 2020
  • Purpose: Research and development of human capital in countries bring sustainable development to the nations. Especially for developing countries, the attraction of foreign direct investment not only brings economic growth to the country but also contributes to improving human capital. This study aims to assess the impact of foreign direct investment on human capital in ASEAN countries. Research design, data and methodology: With data collected from ASEAN countries from 1990 to 2019, panel data analysis is performed with revised model types (the Pooled OLS, Fixed effect model, Random effect model and regression with Driscoll-Kraay standard errors). Result: The results of the regression analysis show that FDI has a positive impact on human capital. At the same time, the study also found that public investment in education also positively affects human capital; the life expectancy factor does not affect human capital. Conclusions: With this research result, the authors also proposed a number of solutions to improve human capital by attracting FDI and improving the efficiency of investment for the education of ASEAN countries. Besides, public expenditure on education also plays an important role in raising human capital. Therefore, investment in education should be promoted further in the future.

Advanced Small-Signal Model of Multi-Terminal Modular Multilevel Converters for Power Systems Based on Dynamic Phasors

  • Hu, Pan;Chen, Hongkun;Chen, Lei;Zhu, Xiaohang;Wang, Xuechun
    • Journal of Power Electronics
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    • 제18권2호
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    • pp.467-481
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    • 2018
  • Modular multilevel converter (MMC)-based high-voltage direct current (HVDC) presents attractive technical advantages and contributes to enhanced system operation and reduced oscillation damping in dynamic MMC-HVDC systems. We propose an advanced small-signal multi-terminal MMC-HVDC based on dynamic phasors and state space for power system stability analysis to enhance computational accuracy and reduce simulation time. In accordance with active and passive network control strategies for multi-terminal MMC-HVDC, the matchable small-signal stability models containing high harmonics and dynamics of internal variables are conducted, and a related theoretical derivation is carried out. The proposed advanced small-signal model is then compared with electromagnetic-transient and traditional small-signal state-space models by adopting a typical multi-terminal MMC-HVDC network with offshore wind generation. Simulation indicates that the advanced small-signal model can successfully follow the electromechanical transient response with small errors and can predict the damped oscillations. The validity and applicability of the proposed model are effectively confirmed.

α-β 필터를 사용한 위상배열 레이더의 실표적 추적 정확도 평가 알고리듬 연구 (A Study for Assessment of Track Accuracy of Phased Array Radar Associated with α-β Filter)

  • 신상진;김완규
    • 한국전자파학회논문지
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    • 제26권9호
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    • pp.828-836
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    • 2015
  • 본 논문은 위상배열 레이더를 사용하여 실제표적을 추적하였을 때 추적 정확도를 평가하기 위한 알고리듬 연구이다. 실표적에 대한 추적 정확도를 평가하기 위해서는 실표적 위치에 대한 정보가 있어야 하지만, 시험비용 및 시험시간의 증대로 인해 위상배열 레이더에서 획득된 데이터만을 사용하여 실표적의 정확도를 평가하는 알고리듬을 제시한다. 이러한 평가 알고리듬은 위상배열 레이더에서 사용된 ${\alpha}-{\beta}$ 추적필터의 잔차로부터 추적 정확도의 지표인 거리오차와 각도 오차의 표준편차를 도출한 결과이며, 통계적 방법으로 sample variance 개념을 사용하게 된다.

전자상거래 보험의 담보범위에 관한 고찰 (A Study on the coverage of e-commerce insurance)

  • 신건훈
    • 무역상무연구
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    • 제27권
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    • pp.129-161
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    • 2005
  • Todays, computers in business world are potent facilitators that most companies could not without them, while they are only tools. They offer extremely efficient means of communication, particularly when connected to Internet. What I stress in this article is the risks accompanied by e-commerce rather than the advantages of Internet or e-commerce. The management of e-commerce companies, therefore, should keep in mind that the benefit of e-commerce through the Internet are accompanied by enhanced and new risks, cyber risks or e-commerce risks. For example, companies are exposed to computer system breakdown and business interruption risks owing to traditional and physical risks such as theft and fire etc, computer programming errors and defect softwares and outsider's attack such as hacking and virus. E-commerce companies are also exposed to tort liabilities owing to defamation, the infringement of intellectual property such as copyright, trademark and patent right, negligent misrepresent and breach of confidential information or privacy infringement. In this article, I would like to suggest e-commerce insurance or cyber liability insurance as a means of risk management rather than some technical devices, because there is not technically perfect defence against cyber risks. But e-commerce insurance has some gaps between risks confronted by companies and coverage needed by them, because it is at most 6 or 7 years since it has been introduced to market. Nevertheless, in my opinion, e-commerce insurance has offered the most perfect defence against cyber risks to e-commerce companies up to now.

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