• 제목/요약/키워드: process measurement

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Consideration on the Non-linearity of Warburg Impedance for Fourier Transform Electrochemical Impedance Spectroscopy

  • Chang, Byoung-Yong
    • Journal of the Korean Electrochemical Society
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    • v.17 no.2
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    • pp.119-123
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    • 2014
  • Here I report on how Fourier Transform Electrochemical Impedance Spectroscopy (FTEIS) overcomes the potential-current linearity problem encountered in the impedance calculation process. FTEIS was first invented to solve the time-related drawback of the conventional impedance technique. The dramatic time reduction of FTEIS enabled the real-time impedance measurement but brought about the linearity problem at the same time. While the conventional method circumvents the problem using the steady-state made by a sufficiently long measurement time, FTEIS cannot because of its real-time function. However, according to the mathematical development reported in this article, the potential step used in FTEIS is proved to avoid the linearity problem. During the step period, the potential and the current are linearized by the electrochemical impedance. Also, Fourier transform of the differentiated potential and current is proved to give the same result of the original ones.

Solar Radiation Measurement and Data Quality Management (태양자원 측정 및 데이터 품질관리)

  • Jo, Dok-Ki;Yun, Chang-Yeol;Kim, Kwang-Deuk;Kang, Young-Heak
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.11a
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    • pp.63.2-63.2
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    • 2010
  • Solar radiation data are used in several forms and for a variety of purposes. The most detailed information we have is beam and diffuse solar radiation on a horizontal surface, by hours, which is useful in simulations of solar processes. Daily data are more often available and monthly total solar radiation on horizontal surface can be used in some process design methods. However, as performance is generally not linear with solar radiation, the use of average may lead to serious errors if non-linearities ara not taken into account. It is also possible to reduce radiation data to more manageable forms by statistical methods. The control of the quality of most measurements is relegated to the control of the measuring instruments and measuring processes themselves. An accurate measurement will usually result from the use of a high-quality instrument that has been accurately calibrated and is properly used by a qualified individual.

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Performance Analysis of the UPC/NPC Algorithm for Guaranteed QoS in ATM Networks

  • Kim, Yong-Jin;Kim, Jang-Kyung;Lee, Young-Hee;Park, Chee-Hang
    • ETRI Journal
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    • v.20 no.3
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    • pp.251-271
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    • 1998
  • It is well known that if usage parameter control/network parameter control (UPC/NPC) functions are used together with a cell loss priority control scheme in ATM networks, the measurement phasing problem can occur. This makes it difficult for a network provider to define and commit the cell loss ratio as a QoS parameter. To solve the problem, we propose a new UPC/NPC algorithm. By using the proposed UPC/NPC algorithm, we can define the cell loss ratios for CLP = 0 and CLP = 0+1 cell streams without the measurement phasing problem under any conditions. We analyzed the performance of the proposed UPC/NPC algorithm. Using a discrete time model for the UPC/NPC architecture with a discrete-time semi-Markov process (DSMP) input model, we obtained the cell discarding probabilities of CLP = 0 and CLP = 0+1 cells streams and showed that more CLP = 0 cells are accepted compared to what was proposed in ITU-T.

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Pressure Analysis on the nozzle wall with PSP (PSP를 이용한 노즐벽면의 압력해석)

  • Kim Ki-Su;Bae Young-Woo;Lee Jea-Woo;Byun Yung-Hwan
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • v.y2005m4
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    • pp.409-412
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    • 2005
  • This paper shows the process of Pressure Sensitive Paint(PSP) measurement on the nozzle wall in M=2.5 supersonic wind tunnel, and compare with the result of the paper that performed the PSP measurement in similar condition in NASA Lewis Research Center.

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Study of Capacitive Tilt Sensor with Metallic Ball

  • Lee, Chang Hwa;Lee, Seung Seob
    • ETRI Journal
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    • v.36 no.3
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    • pp.361-366
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    • 2014
  • In this paper, a new, simple capacitive tilt sensor with a metallic ball is proposed. The proposed tilt sensor has only two electrodes and a metallic ball, and this design assists in managing the inherent contact problem in measuring tilt angles. Capacitive sensing, compared with other types of tilt sensor, has many advantages such as simplicity, noncontact measurement, long-throw linear displacement, and sub-micron plate spacing. Its design and fabrication process are significantly simpler than previous types of tilt sensors. The dimensions of the prototype tilt sensor are $20mm{\times}20mm$, and the diameter of the polystyrene tube is 5 mm with a tube thickness of 0.15 mm. An analytical study of the prototype capacitive tilt sensor was undertaken, and the experimental results demonstrate the relationship between the tilt angles and measured capacitances compared with the analytical study.

The Evaluation of Organizational Effectiveness Based on Balanced Scorecard : A Case of Success of Skandia (BSC 기반의 조직효과성 평가 성공 사례 : 스칸디아 보험회사)

  • Kwon, Sang-Sun;Park, Ji-Hwan
    • Journal of Digital Convergence
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    • v.7 no.2
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    • pp.51-62
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    • 2009
  • Most studies of organizational effectiveness previously done, have measured financial performance such as productivity, efficiency or subjective performance such as a commitment, satisfaction, and turnover intention of employees. However, these measurements have limitations to evaluate a organizational effectiveness in recent knowledge information era because evaluation of organizational effectiveness in knowledge-based society needs measurements in various aspects such as financial, customer, internal business process, and learning and growth. The purpose of this study is to overcome these problems and to introduce an appropriate system for evaluation of organizational effectiveness under knowledge management paradigm. In this paper, we suggest a Balanced Scorecard(BSC) as a new measurement standard of organizational effectiveness in a knowledge information era. The balanced scorecard is designed to help firms that have historically overemphasized short-term financial performance. When measuring organizational effectiveness through Balanced Scorecard(BSC) suggested by Kaplan and Norton[31], it is to present the measurement indices that can cover the limitation of the past evaluation indices of organizational effectiveness.

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Measurement System of the Transverse Temperature Profile of Hot Rolled Strip (열간압연공정에서의 스트립 폭방향온도 모니터링시스템 개발)

  • Lee, Sung-Jin
    • Proceedings of the KSME Conference
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    • 2001.06c
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    • pp.197-201
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    • 2001
  • Output and cost efficiency in the production of hot-rolled strip depend to a large content on the uniformity of geometric and mechanical properties over the length and width of the rolled end product. To ensure the homogeneous temperatures required for this during the rolling process a system to measure and evaluate the transverse temperature profile was developed and implemented in production. The systems used consist of temperature scanners and computers for measurement and data evaluation. The systems have been installed in Kwangyang hot strip mills, in the cases at the exit of the finishing train and at the entry of the coiler. They are used in production to determine the effect of the finishing train and the cooling zone on the technological properties of the hot rolled strip.

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Least Square B-Spline Fitting For Surface Measurement (곡면 측정을 위한 최소 자승 비-스플라인 Fitting)

  • Jung, Jong-Yun;Lisheng Li;Lee, Choon-Man;Chung, Won-Jee
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.12 no.2
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    • pp.79-85
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    • 2003
  • An algorithm for fitting with Least Square is a traditional and an effective method in processing with experimental data. Due to the lack of definite representation, it is difficult to fit measured data with free curves or surfaces. B-Spline is usefully utilized to express free curves and surfaces with a few parameters. This paper presents the combination of these two techniques to process the point data measured from CMM and other similar instruments. This research shows tests and comparison of the simulation results from two techniques.

Development of the wearable ECG measurement system for health monitoring during daily life (일상생활 중 건강모니터링을 위한 착용형 심전도계측 시스템 개발)

  • Noh, Yun-Hong;Jeong, Do-Un
    • Journal of Sensor Science and Technology
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    • v.19 no.1
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    • pp.43-51
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    • 2010
  • In this study, wearable ECG measurement system was implemented for health monitoring during daily life. A wearable belt-type ECG electrode worn around the chest by measuring the real-time ECG is produced in order to minimize the inconvenience in wearing. The measured ECG signal is transmitted via an ultra low power consumption wireless data communications unit to personal computer using Zigbee-compatible wireless sensor node. The ECG monitoring program is developed at end user which is personal computer. The measured ECG contains many noises mainly due to motion artifacts. For ECG signal processing, adaptive filtering process is proposed which can reduce motion artifacts efficiently and accurately than digital filter. The experimental results show that a reliable performance with high quality ECG signal can be achieved using this wearable ECG monitoring system.

Steady Flow Characteristics of Four-Valve Cylinder Heads (실린더헤드 형상에 따른 정상유동 특성)

  • 배충식;정경석
    • Transactions of the Korean Society of Automotive Engineers
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    • v.4 no.5
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    • pp.197-205
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    • 1996
  • The flow characteristics of five different 4-valve cylinder heads were investigated in a steady flow rig using laser-Doppler velocimetry. The tumble flow of each head with pentroof combustion chamber was quantified by nondimensional tumble number using a tumble adaptor. The formation of tumbling vortex was examined in an optical single-cylinder engine which has windows for in-cylinder LDV measurements. Tumble vortex ratio was estimated from the tumble flow measurement. The four-valve cylinder heads with pent-roof combustion chamber showed the tumble vortex from the intake process, which was investigated in the steady flow test. The tumble adaptor which converts the tumble into swirl flow was found to be feasible in predicting the tumble flow in the real engine. The tumble strength in the steady flow test coincides with that in the real engine experiment within 15%. It was found that the steady flow test on the four-valve cylinder heads provides the tip for a better design of cylinder head.

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