• Ocean and Polar Research
• /
• v.36 no.1
• /
• pp.77-85
• /
• 2014

The quality control of ocean observations data is becoming a major issue as real-time observational data and information services have increased recently. Therefore, it is necessary for oceanographic instruments to calibrate. In this paper, we first introduce the CTD calibration system and traceability. Next, CTD calibration procedures and estimation of uncertainty of measurement are described. The expanded uncertainty (k = 2) of the temperature, pressure and conductivity are 0.$0.003^{\circ}C$, $6.0{\times}10^{-5}$ and 0.006 mS/cm respectively. Finally, the excellence of CTD calibration and its measurement capability has been proven by comparing the inter-calibration result of KIOST and Sea-Bird Electronics (SBE). CTD calibration residuals are less than ${\pm}0.0001^{\circ}C$, ${\pm}0.001$ MPa, ${\pm}0.0001$ S/m for SBE 3plus temperature sensor, SBE 19plus pressure sensor and SBE 4C conductivity sensor respectively.

• Proceedings of the KIPE Conference
• /
• 2000.07a
• /
• pp.661-664
• /
• 2000

This paper presents a digital instrument for the power quality analysis in three phase power system where current waveform is non-sinusoidal. It is based on C31 DSP and on a special high-speed data acquisition system. Voltage and current waveforms are acquired and processed by using a simple average power algorithm, The paper also goes on to discuss the performance of an instrument prototype both in terms of accuracy and speed of measurement.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.30 no.12 s.255
• /
• pp.1649-1657
• /
• 2006

Fizeau interferometer is well known optical instrument for measuring the lens profile accurately. The object of this study is focused on the design and optical measuring techniques for large optical components, such as a reflection mirror for astronomical purpose. Measuring of large optical lens, the object could not be moved as small one but the measuring instrument must be moved for the alignment, because of the geometric conditions and the accuracy of the stage. Therefore, a five axis stage is designed to align the Interferometer instead of the measuring object. This instrument will be used for an on machine measuring system in polishing machine for large optical lens.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.51 no.6
• /
• pp.241-251
• /
• 2002

The effect of sensor faults in direct torque control(DTC) based induction motor drives is analyzed and a new Instrument fault detection isolation scheme(IFDIS) is proposed. The proposed IFDIS, which operated in real-time, detects and isolates the incipient fault(s) of speed sensor and current sensors that provide the feedback information. The scheme consists of an adaptive gain scheduling observer as a residual generator and a special sequential test logic unit. The observer provides not only the estimate of stator flux, a key variable in DTC system, but also the estimates of stator current and rotor speed that are useful for fault detection. With the test logic, the IFDIS has the functionality of fault isolation that only multiple estimator based IFDIS schemes can have. Simulation results for various type of sensor faults show the detection and isolation performance of the IFDIS and the applicability of this scheme to fault tolerant control system design.

• ETRI Journal
• /
• v.32 no.4
• /
• pp.548-554
• /
• 2010

The transcutaneous energy transmission system (TETS) composed of a Class-E amplifier may operate at a state away from the optimum power transmission due to the load variation. By introducing the feedback-loop technique, the TETS can keep the optimum state with constant output voltage by adjusting the important design parameters, that is, the duty ratio and frequency of the driving signal and the supply voltage. The relations between these adjusted parameters and the load are investigated. The effectiveness of the feedback technique is validated through a design example with a variable load parameter. The experimental results show that the Class-E amplifier in the feedback loop can keep operating at the optimum state under the condition of up to 50 percent variation of the load value.

• Proceedings of the KIEE Conference
• /
• 2005.07b
• /
• pp.1438-1440
• /
• 2005

A power control and distribution unit(PCDU) plays roles of protection of battery against overcharge by active control of solar array generated power, distribution of unregulated electrical power via controlled outlets to bus and instrument units, distribution of regulated electrical power to selected bus and instrument units, and provision of status monitoring and telecommand interface allowing the system and ground operate the power system, evaluate its performance and initiate appropriate countermeasures in case of abnormal conditions. In this work, we perform the preliminary design of a PCDU scheme for the small LEO Satellite applications. The main constitutes of the PCDU are the battery interface module, the auxiliary supply modules, solar array regulators with maximum power point tracking(MPPT) technology, heater power distribution modules, internal converter modules for regulated bus voltage generation. and instrument power distribution modules.

• The Journal of the Acoustical Society of Korea
• /
• v.32 no.4
• /
• pp.346-353
• /
• 2013

This paper deals with the implementation of a high-quality audio system for karaoke. For improving the key/tempo changes performance, we separated the audio into many musical instrument channels. By separating musical instrument channels, high-quality key/tempo changes can be achieved and we confirmed this using the cross-correlation distribution and the MOS evaluation. The improved audio system was implemented using the TMS320C6747 DSP with fixed/floating-point operations. The implemented audio system can perform the multi-channel WMA decoding, the MP3 encoding/decoding, the wav playing, the EQ, and the key/tempo changes in real time. The WMA channels used for processing the separated instrument channels. The audio system includs the MP3 encoding/decoding function for playing and recording and the wav channel for the effect sound.

• Aerospace Engineering and Technology
• /
• v.13 no.2
• /
• pp.185-193
• /
• 2014

In this study, development process of a design program for Instrument Flight Procedure (IFP) is briefly described. Survey results and corresponding analysis are shown to enhance a market competence of the deliverables. Standards and regulations for IFP design are analyzed to derive the system requirements. Detail development processes and test procedures are explained.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.40 no.1
• /
• pp.120-127
• /
• 1991

The purpose of this study is to develop a fault detection and diagnosis scheme that can monitor process fault and instrument fault of a steam generator. The suggested scheme consists of a Kalman filter and two bias estimators. Method of detecting process and instrument fault in a steam generator uses the mean test on the residual sequence of Kalman filter, designed for the unfailed system, to make a fault decision. Once a fault is detected, two bias estimators are driven to estimate the fault and to discriminate process fault and instrument fault. In case of process fault, the fault diagnosis of outlet temperature, feed-water heater and main steam control value is considered. In instrument fault, the fault diagnosis of steam genrator's three instruments is considered. Computer simulation tests show that on-line prompt fault detection and diagnosis can be performed very successfully.

• Journal of Biomedical Engineering Research
• /
• v.16 no.2
• /
• pp.139-148
• /
• 1995

In this paper we report the device of a multi-channel clinical instrument developed for determi¬nation of the levels of the urinary urobilinogen, glucose, ketone, bilirubin, protein, ascorbic acid, nitrite, pH, occult-blood, specific gravity, and leukocytes semiquantitatively. The test parameters are expressed on the dry test strips as a range of color intensities by chemical reactions. The instrument measures the value of each substance by reading the reflectance light emanated from the test strips. We also designed the reagent strip cassette and loader in order to intercept the outside interference. The loader can be operated semi-automatically. The light source is consisted on light emitting diodes at three specific wavelengths (560 nm, 610 nm, 650 nm). Precision of the system was evaluated by testing a series of commercial control urine samples. Furthermore, the performance of the instrument was compared with two other test methods on the urine samples from 100 persons. Our results showed a good repeatability between tests and a satisfactory agreement between the readings by our instrument and visual evaluation.