• Title/Summary/Keyword: Instrument Error

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Identification of geographical origin of sesame seeds by near infrared spectroscopy (근적외 분석법에 의한 참깨의 원산지 판별)

  • Kwon, Young-Kil;Cho, Rae-Kwang
    • Applied Biological Chemistry
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    • v.41 no.3
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    • pp.240-246
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    • 1998
  • Geographical origin of the Korean, Chinese and Japanese sesame seeds were identified very high accuracy by NIR spectroscopy. The NIR instrument of filter type showed the same accuracy of the monochromator scanning type to identify the geographical origin of the sesame seeds. In case of adulteration between the Korean and Chinese sesame seeds, the ratio of addition could be determined about 10% error level. The reason of identification of geographical origin by NIR spectroscopy, it was supposed to the difference, of oil cake substance.

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The Mechanical Dither Design of Navigation Guide Structure (네비게이션 가이드 구조물의 기계적 진동설계)

  • Lee, Jeong-Ick
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.6
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    • pp.1949-1954
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    • 2010
  • The gyroscopes have been used as a suitable inertial instrument for the navigation guidance and attitude controls. The accuracy as very sensitive sensor is limited by the lock-in region(dead band) due to the frequency coupling between two counter-propagating waves at low rotation rates. This frequency coupling gives no phase difference, and an angular increment is not detected. This problem can be overcome by mechanically dithering the gyroscope. This paper presents the design method of mechanical dither by the theoretical considerations and the verification of the theoretical equations through FEM(Finite Element Method) applications. As a result, the maximum prediction error of resonant frequency and peak dither rate was under 5 percent. The theoretical equations for the mechanical performances of dither can be said to be feasible.

Developing Visual Complexity Metrics for Automotive Human-Machine Interfaces

  • Kim, Ji Man;Hwangbo, Hwan;Ji, Yong Gu
    • Journal of the Ergonomics Society of Korea
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    • v.34 no.3
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    • pp.235-245
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    • 2015
  • Objective: The purpose of this study is to develop visual complexity metrics based on theoretical bases. Background: With the development of IT technologies, drivers process a large amount of information caused by automotive human-machine interface (HMI), such as a cluster, a head-up display, and a center-fascia. In other words, these systems are becoming more complex and dynamic than traditional driving systems. Especially, these changes can lead to the increase of visual demands. Thus, a concept and tool is required to evaluate the complicated systems. Method: We reviewed prior studies in order to analyze the visual complexity. Based on complexity studies and human perceptual characteristics, the dimensions characterizing the visual complexity were determined and defined. Results: Based on a framework and complexity dimensions, a set of metrics for quantifying the visual complexity was developed. Conclusion: We suggest metrics in terms of perceived visual complexity that can evaluate the in-vehicle displays. Application: This study can provide the theoretical bases in order to evaluate complicated systems. In addition, it can quantitatively measure the visual complexity of In-vehicle information system and be helpful to design in terms of preventing risks, such as human error and distraction.

Analysis of Korean Nursing Studies Applied for the Transtheoretical Model (Transtheoretical Model을 적용한 국내 간호연구 분석)

  • Lee, Eun-Hyun;Kim, Jin Sun;Jung, Young Hae
    • Korean Journal of Adult Nursing
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    • v.19 no.4
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    • pp.567-582
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    • 2007
  • Purpose: The purpose of this study was to explore the utilization of the Transtheoretical Model(TTM) for Korean nursing studies on health behaviors and identify the strategies for improvement of further studies. Methods: From a main and seven branch journals on the Korean Society of Nursing Science, a total of 26 studies, which had been conducted based upon the TTM, were selected. The selected studies were analyzed from the September of 2006 to the February of 2007 by the criteria; name of journal, year of publication, health behavior, population, sampling, sample size, research design, instrument (translation process, reliability and validity), and statistical analysis. Results: TTM on the Korean nursing studies was mainly applied for smoking cessation or exercise with elderly or middle aged women. The research findings could not be generalized with the limitation of the use of non representative samples. The most frequently used research design was a cross-sectional survey. Some studies had a lack of reliable and valid instruments, so that the internal validity of the study findings may be threatened. Statistically related problems increased type I error and decreased power. Conclusion: Korean nursing studies based on TTM can be the beginning stage in quality and quantity.

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Adjustment of load correlation coefficient for advanced load management (부하관리 개선을 위한 부하 상관계수 산정에 관한 연구)

  • Park, Chang-Ho;Cho, Seong-Soo;Kim, Gi-Hyun;Im, Jin-Soon;Kim, Du-Bong;Kim, Jae-Chul
    • Proceedings of the KIEE Conference
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    • 1999.07c
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    • pp.1267-1269
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    • 1999
  • This paper studies on arrangement of load correlation coefficient for advanced load management. To accurate load correlation coefficient, we used two real factors, electrical energy(kWh) and peak load current of pole transformers, acquired by measuring instrument. Out of several correlation equations, we find that the quadratic equation is the most accurate to express peak load current and working electrical energy. If the data is located in the outside of ${\pm}3{\sigma}$ it is discarded. For load management, we rearranged load correlation coefficient considering +2${\sigma}$ at load correlation equation. Comparing conventional load correlation coefficient with rearranged one, we can get the result of error reduced and it is adjacent to the actual data. It will be used peak load forecasting from working electrical energy and we are able to prevent from the damaging of pole transformer due to overload.

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SHM-based probabilistic representation of wind properties: Bayesian inference and model optimization

  • Ye, X.W.;Yuan, L.;Xi, P.S.;Liu, H.
    • Smart Structures and Systems
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    • v.21 no.5
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    • pp.601-609
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    • 2018
  • The estimated probabilistic model of wind data based on the conventional approach may have high discrepancy compared with the true distribution because of the uncertainty caused by the instrument error and limited monitoring data. A sequential quadratic programming (SQP) algorithm-based finite mixture modeling method has been developed in the companion paper and is conducted to formulate the joint probability density function (PDF) of wind speed and direction using the wind monitoring data of the investigated bridge. The established bivariate model of wind speed and direction only represents the features of available wind monitoring data. To characterize the stochastic properties of the wind parameters with the subsequent wind monitoring data, in this study, Bayesian inference approach considering the uncertainty is proposed to update the wind parameters in the bivariate probabilistic model. The slice sampling algorithm of Markov chain Monte Carlo (MCMC) method is applied to establish the multi-dimensional and complex posterior distribution which is analytically intractable. The numerical simulation examples for univariate and bivariate models are carried out to verify the effectiveness of the proposed method. In addition, the proposed Bayesian inference approach is used to update and optimize the parameters in the bivariate model using the wind monitoring data from the investigated bridge. The results indicate that the proposed Bayesian inference approach is feasible and can be employed to predict the bivariate distribution of wind speed and direction with limited monitoring data.

The Mediating and Moderating Roles of Safety-specific Transformational Leadership on the Relationship between Barrier to and Intention of Reporting Medication Errors (투약오류보고장애요인과 투약오류보고의도의 관계에서 수간호사의 안전 관련 변혁적 리더십의 매개, 완충효과)

  • Kim, Myoung Soo
    • Korean Journal of Adult Nursing
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    • v.27 no.6
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    • pp.673-683
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    • 2015
  • Purpose: This study was aimed to identify the mediating and moderating effects of safety-specific transformational leadership on the relationship between barrier to and intention of reporting medication errors. Methods: Two hundred thirty seven nurses from seven different hospitals participated in the study. Safety-specific transformational leadership was measured by an instrument with 10 items, barrier to reporting medication errors with 16 items, and intention of reporting medication errors with 3 items. The data was collected from September to October 2012. Descriptive statistics, factor analysis, t-test, ANOVA, Pearson correlation coefficient and a hierarchial regression analysis were used. Results: There were significant negative correlations between the subcategories of barrier to reporting medication errors and intention of reporting medication errors (r=-.16~-.27, p<.001), and a positive correlation between the intention and safety-specific transformational leadership (r=.25, p<001). Transformational leadership was a mediator between barrier to and intention of reporting medication errors. Conclusion: Safety-specific transformational leadership mediated the relationships between barrier to and intention of reporting medication errors. Enhancing safety-specific transformational leadership of nursing unit managers is necessary to increase the intention to reporting medication errors.

A Study on the MTF Graphics using Simpson Approximation (심프슨 근사법을 이용한 MTF 그래프 작성에 관한 연구)

  • Che, Gyu-Shik;Chang, Won-Seok;Oh, Jake
    • Journal of Advanced Navigation Technology
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    • v.16 no.2
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    • pp.401-408
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    • 2012
  • There is a clear need for characterizing optical components with the growing role played by optical devices in measurement, communication, and photonics. A basic and useful measuring parameter to meet this need, especially for imaging systems, is the Modulation Transfer Function, or MTF. Over the past few decades new instrument, including the laser interferometer, the CCD camera, and the computer have revolutionized the measurement and calculation of the MTF. This has made what was tedious and involved into virtually an instantaneous measurement. We proposed a Simpson approxiamtion method to create MTF graph and illustrated real example to verify its method in this paper. This method is very useful while it is very useful because its error is very minor and small although its approximation.

Baseline Design and Performance Analysis of Laser Altimeter for Korean Lunar Orbiter

  • Lim, Hyung-Chul;Neumann, Gregory A.;Choi, Myeong-Hwan;Yu, Sung-Yeol;Bang, Seong-Cheol;Ka, Neung-Hyun;Park, Jong-Uk;Choi, Man-Soo;Park, Eunseo
    • Journal of Astronomy and Space Sciences
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    • v.33 no.3
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    • pp.211-219
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    • 2016
  • Korea's lunar exploration project includes the launching of an orbiter, a lander (including a rover), and an experimental orbiter (referred to as a lunar pathfinder). Laser altimeters have played an important scientific role in lunar, planetary, and asteroid exploration missions since their first use in 1971 onboard the Apollo 15 mission to the Moon. In this study, a laser altimeter was proposed as a scientific instrument for the Korean lunar orbiter, which will be launched by 2020, to study the global topography of the surface of the Moon and its gravitational field and to support other payloads such as a terrain mapping camera or spectral imager. This study presents the baseline design and performance model for the proposed laser altimeter. Additionally, the study discusses the expected performance based on numerical simulation results. The simulation results indicate that the design of system parameters satisfies performance requirements with respect to detection probability and range error even under unfavorable conditions.

Interpretation of Physical Properties of Marine Sediments Using Multi­Sensor Core Logger (MSCL): Comparison with Discrete Samples

  • Kim, Gil-Young;Kim, Dae-Choul
    • Journal of the korean society of oceanography
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    • v.38 no.4
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    • pp.166-172
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    • 2003
  • Multi­Sensor Core Logger (MSCL) is a useful system for logging the physical properties (compressional wave velocity, wet bulk density, fractional porosity, magnetic susceptibility and/or natural gamma radiation) of marine sediments through scanning of whole cores in a nondestructive fashion. But MSCL has a number of problems that can lead to spurious results depending on the various factors such as core slumping, gas expansion, mechanical stretching, and the thickness variation of core liner and sediment. For the verification of MSCL data, compressional wave velocity, wet bulk density, and porosity were measured on discrete samples by Hamilton Frame and Gravimetric method, respectively. Acoustic impedance was also calculated. Physical property data (velocity, wet bulk density, and impedance) logged by MSCL were slightly larger than those of discrete sample, and porosity is reverse. Average difference between MSCL and discrete sample at both sites is relatively small such as 22­24 m/s in velocity, $0.02­-0.08\;g/\textrm{cm}^3$ in wet bulk density, and 2.5­2.7% in porosity. The values also show systematic variation with sediment depth. A variety of factors are probably responsible for the differences including instrument error, various measurement method, sediment disturbance, and accuracy of calibration. Therefore, MSCL can be effectively used to collect physical property data with high resolution and quality, if the calibration is accurately completed.