• 제목/요약/키워드: Analysis Techniques

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The Role of NMR in the Field of Quantitative Analysis

  • Lee, Sueg-Geun
    • 한국자기공명학회논문지
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    • 제20권3호
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    • pp.87-94
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    • 2016
  • Although NMR technique has been using in many areas of chemistry, its merit on quantitative analysis seems not to acknowledge greatly because of the many inferior intrinsic aspects, particularly its sensitivity. Recently, new NMR techniques, high-field NMR, and demands for cutting edge techniques of analysis, however, seem to change the role of NMR spectroscopy in this field. This review shows the application of NMR development in quantitative analysis and will discuss the basic idea, limitations, and pitfalls. Then it will show you several successful applications applied in quantitative analysis and you will see how useful and accurate method it is.

Image analysis를 통한 다공성 시멘트 모르타르 복합체 내 공극량 산출 (An Analysis of the Air Void Volume Image Analysis of Porous Cement Mortar Composites)

  • 손다솜;이종구
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2021년도 봄 학술논문 발표대회
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    • pp.211-212
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    • 2021
  • This study was conducted to derive quantitative air void volume calculation techniques in various complexes with porosity. Calculation of voids in a complex is an essential factor in improving mechanical properties, and quantitative measurement techniques are needed because the environment is not constant to apply the currently used ASTM criteria. Using the analysis technique obtained through 2D image analysis, it is believed that meaningful results can be derived through Micro CT analysis results and cross-check later.

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A simple and efficient data loss recovery technique for SHM applications

  • Thadikemalla, Venkata Sainath Gupta;Gandhi, Abhay S.
    • Smart Structures and Systems
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    • 제20권1호
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    • pp.35-42
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    • 2017
  • Recently, compressive sensing based data loss recovery techniques have become popular for Structural Health Monitoring (SHM) applications. These techniques involve an encoding process which is onerous to sensor node because of random sensing matrices used in compressive sensing. In this paper, we are presenting a model where the sampled raw acceleration data is directly transmitted to base station/receiver without performing any type of encoding at transmitter. The received incomplete acceleration data after data losses can be reconstructed faithfully using compressive sensing based reconstruction techniques. An in-depth simulated analysis is presented on how random losses and continuous losses affects the reconstruction of acceleration signals (obtained from a real bridge). Along with performance analysis for different simulated data losses (from 10 to 50%), advantages of performing interleaving before transmission are also presented.

마코프 프로세스를 이용한 원자로 보호계통의 신뢰도 분석 (Reliability Analysis of the Reactor Protection System Using Markov Processes)

  • Jo, Nam-Jin
    • Nuclear Engineering and Technology
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    • 제19권4호
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    • pp.279-291
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    • 1987
  • 현재 원자력발전소의 확률론적 위해도 평가에 사용되는 사상 수목이나 고장수목 기법은 부품이나 계통의 이원적상태와 정적 묘사에 근거하고 있다 이 기법이 대부분의 안전해석에는 적합하지만, 요사이 점차 중요관심사가 되고 있는 발전소의 이용률 측정이나 기술 사양서 평가 같은 문제를 정확하게 다루기 위해서는 마코프 신뢰도 분석과 같은 보다 진보된 기법이 필요하다. 이 논문은 가압경수로의 원자로 보호계통을 위한 마코프 신뢰도 모델을 기술하고 기술사양서의 두 검사 절차를 분석한 결과를 제시한다.

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제철용 고로의 유한요소해석 (Finite Element Analysis for Iron-Making Furnace)

  • 이만승;백점기;이제명
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2004년도 가을 학술발표회 논문집
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    • pp.245-253
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    • 2004
  • There has been recent demand for extending the life of age-degraded structures and equipment by such techniques as diagnosis, maintenance, safety assessment, and estimating residual life on iron-making plants and hydraulic, thermal, and nuclear power plants. These techniques take into account comprehensive scenarios that may cause malfunction and structural damage and allow an assessment of risk based on the likely scenarios. In particular the safety assessment and residual life estimation of age-degraded ships and equipment facilities require consideration of various factors such as mechanical and thermal stresses, corrosion, hardness, load variation due to changes of operating condition, crack generation and strength reduction of material by fatigue. In this study, a detail thermal stress analysis, one of useful techniques of safety assessment and maintenance, is performed on a blast furnace by using general FEM code (MSC/NASTRAN).

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Use Case에 의한 소프트웨어 규모 예측 방법에 대한 실증적 연구 (An Empirical Study of Software Size Estimation Techniques by Use Case)

  • 서예영;이남용
    • 한국전자거래학회지
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    • 제6권2호
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    • pp.143-157
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    • 2001
  • There has been a need for predicting development efforts and costs of the system during the early stage of the software process and hundreds of metrics have been proposed for computer software, but not all provide practical support to the software engineer. Some demand measurement that is too complex, others are so esoteric that few real-world professionals have any hope of understanding them, and others violate the basic intuitive notions of what high-quality software really is. It is worthwhile that metrics should be tailored to best accommodate specific products and processes after grasping their good and no good point. This paper describes two size estimation techniques, the Karner technique and the Marchesi technique, and compares and analyzes them with proposed evaluation criteria. Both techniques are to estimate software size analyzed by use case that is mainly described during the object-oriented analysis phase. We also present an empirical comparison of them, both are applied in the Internet Medicine Prescription System. We also propose some guidance for experiments based on our analysis. We believe that it should be facilitating project management more effective by adjusting software metrics properly.

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리아프노브 분석법 기반 비선형 적응제어 개요 및 연구동향 조사 (Nonlinear Adaptive Control based on Lyapunov Analysis: Overview and Survey)

  • 박진배;이재영
    • 제어로봇시스템학회논문지
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    • 제20권3호
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    • pp.261-269
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    • 2014
  • This paper provides an overview of the basics and recent studies of Lyapunov-based nonlinear adaptive control, the aim of which is to improve or maintain the performance and stability of the closed-loop system by cancelling out the presumable uncertainties in the nonlinear system dynamics. The design principles are essentially based on Lyapunov's direct method. In this survey, we provide a comprehensive overview of Lyapunov-based nonlinear adaptive control techniques with simplified effective design examples, which are to be elaborated as related recent results are gradually shown. The scope of the survey contains research on singularity problems in adaptive control, the techniques to deal with linearly and nonlinearly parameterized uncertainties, robust neuro-adaptive control, and adaptive control methodologies combined with various nonlinear control techniques such as sliding-mode control, back-stepping, dynamic surface control, and optimal/$H_{\infty}$ control.

A Survey: application of geometric modeling techniques to ship modeling and design

  • Ko, Kwang-Hee
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제2권4호
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    • pp.177-184
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    • 2010
  • In this study, geometric modeling techniques and their application to ship modeling and design are presented. Traditionally the hull shape is defined by using curves called the lines and various necessary computations are performed based on the discrete points obtained from the lines. However, some applications find difficulty in using the lines such as seakeeping analysis, which requires the computation of wetted part that is changing dynamically over time. To overcome such a problem and increase accuracy and efficiency in computation, two essential geometric modeling techniques, surface modeling and surface-to-surface intersection, are introduced and their application to ship modeling and analysis including hydrostatic computation, slamming and seakeeping analyses is presented.

요인배치법에 의한 기어용 소재의 마찰계수 분석 (Analysis of Friction Coefficient for Hydraulic Actuator Materials using Statistical Techniques)

  • 배효준;조연상;우규성;박흥식
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2003년도 학술대회지
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    • pp.307-312
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    • 2003
  • The average frictional coefficient was used generally to analyze the moving state of lubricated machine. But It is difficult of getting the correct friction coefficient because the average frictional coefficient of it is progressed always unstably with a large amplitute on driving condition. If correct analysis of frictional coefficient on working condition for lubricated machine can be possible, it can be effect on diagnosis of lubricated machine. The purpose of this study is carried out to get the working condition with a minimum frictional coefficient of transmission gear materials using statistical techniques.

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Yogurt의 향미성분과 분석기술 (Yogurt Flavor Compounds and Analytical Techniques)

  • 장은정;곽해수
    • Journal of Dairy Science and Biotechnology
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    • 제18권1호
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    • pp.61-72
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    • 2000
  • Consumers primarily consider flavor when they take yogurt. Recent researches on yogurt flavor productron its analytical technique have been extensively developed. These studies have provided a better understanding on the role of starter culture microorganisms on flavor formation and degradation. Yogurt volatile flavor compounds produced by the lactic cultures include acetaldehyde, diacetyl, ethanol and organic acid. Among them, acetaldehyde is recognized as a principal flavor component. since yogurt contains a delicate and low intense flavor, mild sample isolation techniques and sensitive identification means might be used. This paper attempts to discuss recent findings in yogurt flavor and to describe the application of yogurt flavor separation techniques. The section on practical aspects of culture selection based on flavor compound production and flavor analysis is also included.

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