• Title/Summary/Keyword: Instrumental Error

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Development of CAMPform2D Preprocessor for Forming Process U sing Convenient Input Method (편리한 입력방식의 단조공정해석을 위한 CAMPform 2D의 Preprocessor 개발)

  • 박성균;이상헌;이강수
    • Korean Journal of Computational Design and Engineering
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    • v.9 no.2
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    • pp.133-142
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    • 2004
  • CAMPfonn2D is a Finite Element Method (FEM) based process simulation system designed to analyze two dimensional (2D) flow of various metal forming processes. It enables designers to analyze metal forming processes on the computer rather than the shop floor using trial and error and provides vital information about material and thermal flow during the forming process to facilitate the design of products. CAMPfonn2D can be used by companies, research institutes and industrial applications to analyze forging, extrusion, drawing, heading, upsetting and many other metal forming processes. Also, process simulation using CAMPfonn2D can be instrumental in cost, quality and delivery improvements at leading companies. Today's competitive pressures require companies to take advantage of every tool for rapid manufacturing of well-designed product. So, the preprocessor of simulation program must be easy to use to speed-up design. In this paper, we introduce new version of Preprocessor and show how easy to use it. And, Preprocessor will prove itself to be easy and extremely effective.

Self-Tuning PID Control of Systems with Time-Varying Delays (시변 지연시간이 존재하는 시스템의 자기동조 PID 제어)

  • 남현도;안동준
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.39 no.4
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    • pp.364-370
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    • 1990
  • In this paper, we propose a self-tuning PID controller for unknown systems with time-varying delay. Using pole placement equations, we derive the controller that can be extended to the multi-step time delay case. The time-varying delays are estimated by a prediction error delay method using multiple predictors. Since the order of the estimation vector is not increased, the persistant exciting condition of control input is alleviated. Since the least square method gives biased parameter estimates for colored noise cases, the recursive instrumental variable method is used to estimate system parameters. The computational burden of the proposed method is less than the conventional adaptive methods. Computer simulations are performed to illustrate the efficiency of the proposed method.

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Grammaticality Judgement and Error Correction by Children with Developmental Language Impairments (경계선지능 언어발달장애아동과 일반아동의 문법성 판단 및 오류수정 - 조사를 중심으로 -)

  • Lim, Jong-Ah;Hwang, Min-A
    • Speech Sciences
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    • v.13 no.2
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    • pp.59-72
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    • 2006
  • In the present study, we investigated the grammaticality judgement skills of children with developmental language impairments. The participants included 20 children with language impairments of ages ranging from 7 to 9 years and of IQ's ranging from 71 to 84, and 40 normally developing children. Twenty normal children were matched with the language impaired children in their language ages and the other 20 normal children were matched with the language impaired children in their chronological ages. The children were asked to judge the grammatical correctness of 48 short sentences, half of which were ungrammatical sentences containing incorrect case-markers and the other half were grammatically correct sentences. Four types of case-markers including nominative "i/ga", accusative "ul/lul", locative "e," and instrumental "ro" were systematically changed to generate the ungrammatical sentences. The language impaired children performed worse than both groups of normally developing children in detecting the ungrammatical sentences and in correcting the case-markers of those sentences. In detecting the errors of ungrammatical sentences, the language impaired children exhibited variable performances across the different case-markers.

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Measurement Uncertainty of Arsenic Concentration in Ambient PM2.5 Determined by Instrumental Neutron Activation Analysis (기기 중성자방사화분석을 이용한 대기 중 PM2.5 내 Arsenic 농도 분석의 측정 불확도)

  • Lim, Jong-Myoung;Lee, Jin-Hong;Moon, Jong-Wha;Chung, Yong-Sam
    • Journal of Korean Society of Environmental Engineers
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    • v.30 no.11
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    • pp.1123-1131
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    • 2008
  • In this study, measurement uncertainty of instrumental neutron activation analysis was evaluated for ambient As concentration in PM2.5. Expanded uncertainties of the measurements were calculated by applying both ISO-GUM approximation and Monte Carlo Simulation(MCS). The estimate of As concentration on a specific day by the Monte Carlo Simulation differed from that of ISO-GUM approximation by less than 4%. Relative expanded uncertainties of As concentrations from a total number of 60 PM2.5 samples were also estimated to be more or less than 10% with 95% confidence level using the Monte Carlo Simulation. Sensitivity test of the measurement uncertainties showed that $\gamma$-ray counting error(62.3%), efficiency(18.5%), air volume(12.3%), neutron flux(2.3%), and absolute gamma-intensity(1.8%) are major factors of uncertainty variations.

A Study on Landscape Architecture Planning and Design as Communicative Action (의사소통 행위로서의 조경계획 및 설계에 대한 연구)

  • 김연금;이규목
    • Journal of the Korean Institute of Landscape Architecture
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    • v.31 no.5
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    • pp.73-85
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    • 2003
  • With more and more people paying attention to substantial democracy, participatory democracy is presented as a practical strategy and an index of Korean democracy. In this social and political atmosphere, participation in environmental planning and design is essential. Nonetheless, the true meaning of “participation” is not used properly because many people do not understand it correctly, The concept of social and political participation is “the action or attempt of ordinary members of society for affecting on the result of decision making.” Based on this concept, participation is accomplished through conventional means and as a form of mobilization in environmental planning and desist Most of the theories on public participation in landscape architecture are technical theories. Therefore, this paper proposes that planning and design of landscape architecture be understood as a communicative action that aims to enable stakeholders to reach a consensus through communication. This study offers the framework of theory to understand and practice planning and design of landscape architecture as a communicative action, after reviewing communicative action theory and communicative planning theory. Results suggest that communicative action theory should be accepted in landscape architecture to overcome the shortcomings of instrumental rationality -- the same way planning theory accepted this theory --and to join the culture of experts focusing on the artistic truth and the culture of life of the world. In addition, accepting communicative action theory enables the acquisition of the instrumental effect and social learning effect and the making of social capital. This study also suggested prerequisite for using the method. There should be change in the social institution and in individual action. In addition the method is composed of three steps: creating the atmosphere for communication; communicating, and; reaching a consensus among stakeholders. Finally, raising the possibility of applying the theory presented in this study requires the accumulation of know-how through trial and error.

Intercomparison and Determination of Trace Elements in Urban Dust by Neutron Activation Analysis (중성자방사화분석법을 이용한 대기분진중의 미량원소 비교분석)

  • Chung, Yong-Sam;Moon, Jong-Hwa;Kim, Sun-Ha;Park, Kwang-Won;Kang, Sang-Hun
    • Analytical Science and Technology
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    • v.13 no.2
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    • pp.179-188
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    • 2000
  • Trace elements in air samples artificially loaded on filters with urban dust and the bulk material of urban dust as an environmental sample were determined non-destructively using instrumental neutron activation analysis. Standard reference material (Urban Dust, SRM 1648) of the National Institute of Standard and Technology was used for the analytical quality control. The relative error for 37 elements was less than 15% and the standard deviation was less than 10%. 29 elements in the urban dust and 21 elements in the loaded filter sample were determined respectively. To evaluate the proficiency and reliability of the measurement, data intercomparison was performed and 39 analytical laboratories participated in the analysis using different analytical methods; neutron activation analysis, particle induced X-ray emission analysis, X-ray fluorescence analysis and atomic absorption spectrometry. Z-scores were calculated using the standard deviation of the laboratorie's mean as target standard deviation, and a good result was obtained that the values fall between -1 and +1 except some elements.

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A Proposal of Digital Photo-Biometry of MRD1 and New Levator Function Test (디지털 사진을 이용한 MRD1의 계측과 새로운 위눈꺼풀 올림근 근력 측정법의 제안)

  • Lee, Seungkook;Park, Sung Gyu;Baek, Rong-Min
    • Archives of Plastic Surgery
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    • v.33 no.4
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    • pp.521-524
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    • 2006
  • Purpose: The history of biometry dates back to ancient Greek. The ideal body ratio from biometry is used as a guideline in many works of art. Biometry is also used as a medical standard to determine normal or abnormal. Since the biometry of face is so complicated, many surgeons tend to regard preoperative evaluation as a bother and substitute medical records with some photographs. We introduce a new method to measure $MRD_1$ and levator function using digital photographs, which becomes widely used lately. Methods: $MRD_1$ can be measured with the primary-gaze-view photo which is magnified by PhotoshopR 7.0.1. The distance from coneal reflex of ring flash to upper eyelid margin is converted to mm-unit using the piece of ruler attached on the patient's face. Levator function can be measured with up-gaze-view photo and down-gaze-view photo which are superimposed on another. The excursion distance of upper eyelid margin (a) and the excursion distance of eyebrow (b) are measured respectively. The levator function can be assessed through subtraction of two values (a-b). This method is simple and precise and can be applied directly to patient without photos. Results: Using magnified digital photos and computer, this method can reduce personal error and instrumental error. Taking some digital photos doesn't take long time, so it can reduce the effort of preoperative evaluation and discomfort of patients. Conclusion: Digital photo-biometry is useful for retrospective study. Especially reducing personal error, it is useful when the number of specimens is huge. New levator function test is much more useful for Asian-specific eyes than Berke's method allowing frontalis muscle compensation.

Determination of Iodine Contents in Ten kinds of Frequently used Oriental Herb Medicinal Products for Cancer Patient (암환자에게 다빈도로 활용되는 한약제제 10종에 대한 요오드의 함량 분석)

  • Lee, Chang-Hee;Choi, Jung-Eun;Kim, Sun-Ha;Chung, Yong-Sam;Moon, Jong-Hwa;Yoo, Hwa-Seung
    • Journal of Korean Traditional Oncology
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    • v.16 no.1
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    • pp.41-53
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    • 2011
  • Background and Objectives: Iodine is an essential constituent of the thyroid hormones associated with the growth and development of humans and animals as an inorganic nutrition. This element may be accumulated in human blood, tissues and body through the intake of foodstuffs, a beverage, a nutritional supplement and a medicine, among others. The aim of the research is to find out a better medicinal stuff for the thyroid cancer patient who required a low level of iodine diet. Methods: Neutron activation analysis (NAA) used for the iodine analysis is one of nuclear analytical techniques using radiation and radioisotopes and very useful as sensitive analytical technique for performing both qualitative and quantitative multi-elemental non-destructive analysis of major, minor and trace components in variety of environmental and biological materials. In this study, iodine contents in ten kinds of oriental herb medicinal products, which is frequently used to cancer patients are determined by using instrumental neutron activation analysis (INAA) at the HANARO research reactor. The samples prescribed are manufactured as powdered form for taking medicine easily. The analytical quality control is performed to assure an uncertainty of the measurement and to compensate the measured data using a biological certified reference material, NIST SRM 1572, Citrus Leaves. The measured value is $1.89{\pm}0.35mg/kg$, and the relative error is 2.88%, and relative standard deviation is 19 % due to high counting error by small counts of gamma ray spectrum. The standard deviations for other elements such as Cl, K, Mn and Na were in the range of 2 to 8%. Result: The level of iodine contents of Biki-huan, Chungryong-huan and Chungcho-huan, samples detected is less than 6 mg/kg except Hangam Plus sample (more than 210 mg/kg) and six samples were not detected. Iodine in the samples of Shoxiho-tang, Shopunghualhyl-tang, Shocungryong-tang, Banhasaxim-tang, Insampaedox-san and Myunyuk Plus were not measured, but possible level of content can be estimated from the detection limits. In addition, the concentrations of some major elements like Cl, K, Mn, Na, in the samples were determined with the detection limits. Conclusions: Most of samples showed low iodine contents of less than 6 mg/kg but it turned out that most of testing samples can be used to classify the level of iodine diet samples considering the recommended low level of iodine diet 50 ${\mu}g$/day, and a better medicinal stuff for the thyroid cancer patient can be found.

The Effect of Environmental Regulation Considering the Endogeneity on the Productivity of Korean Manufacturing Sectors (내생성을 고려한 환경규제 강화가 우리나라 제조업 부문 생산성에 미친 영향 분석)

  • Kim, Taeyoung;Kim, Hongkyun
    • Environmental and Resource Economics Review
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    • v.26 no.4
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    • pp.473-498
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    • 2017
  • This study examines the effect of environmental regulation considering the endogeneity on the productivity of Korean manufacturing industry based on the Porter hypothesis using data from the Mining and Manufacturing Survey, Survey of Research and Development in Korea, and Environmental Statistics Portal from 2003 to 2013 with fixed effect model. In order to eliminate the bias of the missing variables that may occur in the existing studies, we analyze factors affecting productivity such as market competition, R&D investment as explanatory variables. And, in order to eliminate measurement error and inverse causality, we use instrumental variable approach. The main results are as follows. First, our findings that the environmental regulation improve the productivity of Korean manufacturing in the long-run support the Porter hypothesis. Second, our findings suggest that measurement error and reverse causality are main sources of the endogeneity, while omitted variable is not. Finally, environmental technology R&D has reduced productivity in the short-run.

Sensitivity analysis of satellite-retrieved SST using IR data from COMS/MI

  • Park, Eun-Bin;Han, Kyung-Soo;Ryu, Jae-Hyun;Lee, Chang-Suk
    • Korean Journal of Remote Sensing
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    • v.29 no.6
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    • pp.589-593
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    • 2013
  • Sea Surface Temperature (SST) is the temperature close to the ocean's surface and affects the Earth's atmosphere as an important parameter for the climate circulation and change. The SST from satellite still has biases from the error in specifying retrieval coefficients from either forward modeling or instrumental biases. So in this paper, we performed sensitivity analysis using input parameter of the SST to notice that the SST is most affected among the input parameter. We used Infrared (IR) data from the Communication, Ocean, and Meteorological Satellite (COMS)/Meteorological Imager (MI) from April 2011 to March 2012. We also used the Global Space-based Inter-Calibration System (GSICS) correction to quality of the IR data from COMS. SST was calculated by substituting the input parameters; IR data with or without the GSICS correction. The results of this sensitivity analysis, the SST was sensitive from -0.0403 to 0.2743 K when the IR data were changed by the GSICS corrections.