• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.6 no.2
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• pp.45-53
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• 1995

In mobile communication, the performance of QAM technique is poor under deep fading even though Rayleigh channel characteristics are estimated and compensated. In this paper, we analyze the performance of 3/4 Trellis coded 16QAM in Rayleigh channel where burst errors are randomized by bit reversal block interleaver, and TCM coder is designed by computer search to be adequate for Rayleigh channel. The simulation results show that the interleaver has 2dB gain, the modified Viterbi decoder has 2.5dB, and diversity has 9dB gain at $P_{b}b/=10^{-3}$. This indicates that the 3/4 TC 16QAM is applicable to digital mobile communication with good performance.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.1
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• pp.212-218
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• 2002

This research is the development of a distributed tactile sensor using PVDF film far the detection of the contact state. The prototype of the tactile sensor with 8$\times$8 taxels was fabricated using PVDF film and flexible circuitry. In the fabrication procedure, the electrode and the common electrode patterns are attached to the both side of the 28${\mu}m$ thickness PVDF film. The sensor is covered with polyester film for insulation. The signals of a contact pressure to the tactile sensor are sensed and processed in the DSP system in which the signals are digitalized and filtered. And the signals are integrated for taking the force profile. The processed signals of the output of the sensor are visualized to take the shape and force distribution of the contact object in personal computer. The usefulness of the sensor system is verified through the sensing examples.

• Korean Journal of Food Science and Technology
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• v.13 no.1
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• pp.67-73
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• 1981

An inulase from Streptomyces chibaensis was purified about 120-fold with the yield of 38 by ethanol precipitation, DEAE-cellulose chromatography and Sephadex G-200 gel-filtration. The purified enzyme showed the maximal activity at pH 6.5 and was fairly stable between pH $5.0{\sim}9.0$ The enzyme was slightly activated by $Mn^{++},\;Mg^{++}\;and\;Co^{++}$, and markedly inactivated by $Hg^{++}\;and\;Ag^{+}$. The inulase was characterized as a typical endo-inulase which hydrolyzed inulin in a random manner and Km for the inulin was $4.54{\times}10^{-4}M$.

• Journal of Pharmaceutical Investigation
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• v.36 no.4
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• pp.245-251
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• 2006

The novel microsphere blending and multiple emulsion method by single process was tried to prepare sustained release microspheres which release a physiologically active substance for long periods of time. A drug was separately dissolved in each of two or more oils containing biodegradable polymers to give the primary oil phases. The primary oil phases were dispersed in single aqueous phase in succession. From the drug-dispersed solution, the organic solvent was removed to produce microspheres. The accelerated drug release from the microsphere formulation prepared by single process through the multiple emulsion method was very similar to a physical blending of separately prepared microspheres using the same polymers. But long term release was not same. In this study, leuprorelin acetate loaded poly(lactide-co-glycolide) microsphere formulation for one-month delivery was developed by the multi-emulsion method followed by solvent extraction/evaporation method.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.371-372
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• 2006

In this paper, we propose a method that measures quality of digital correlator. Quality of digital correlator in field of image composition of radio astronomy have as important position for acquisition of radio wave image with high precision. Digital correlator should have wide bandwidth and high precision to study on deep space. Digital correlator, therefore, should be designed to have high speed processing and high precision. But, real time measurement of quality of digital correlator using acquisition data is difficult to compare accuracy of result because digital correlator should process a large quantity of data with high speed. Measurement method of quality, also, has intricate implementation of experiment equipment. this paper present methods that compose experiment equipment without external installation easily and verify quality of digital correlator perfectly.

• Geotechnical Engineering
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• v.3 no.4
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• pp.31-40
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• 1987

A helical probe test (HPT) suitable for in.situ soil exploration to a shallow depth and compaction control were developed and tested in different soils alongside traditional in-situ tests, including Standard Penetration Test (SPT), Cone Penetration Test (CPT) and in-situ density test. The helical probe test is economical and can be performed by a single person. The torque necessary to insert the probe Is used as a measure of soil characteristics. It was found that: the HPT test correlates well with the SPT test and the correlation is not sensitive to the soil type; the HPT test correlates well with the CPT test, but the correlation is sensitive to the soil type; the HPT torque provides a sensitive measure of relative compaction rind in-situ dry density of compacted soils; the reverse torque ratio decreases with increasing average grain sloe.

• Proceedings of the KSME Conference
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• 2001.06b
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• pp.42-47
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• 2001

Analyzing the ECG signal, we can find heart disease, for example, arrhythmia and myocardial infarction, etc. Particularly, detecting arrhythmia is more important, because serious arrhythmia can take away the life from patients within ten minutes. In this paper, we would like to introduce the signal processing for ECG analysis and the device made for wireless communication of ECG data. In the signal processing, the wavelet transform decomposes the ECG signal into high and low frequency components using wavelet function. Recomposing the high frequency bands including QRS complex, we can detect QRS complex and eliminate the noise from the original ECG signal. To recognize the ECG signal pattern, we adopted the polynomial approximation partially and statistical method. The ECG signal is divided into small parts based on QRS complex, and then, each part is approximated to the polynomials. Comparing the approximated ECG pattern with the database, we can detect and classify the heart disease. The ECG detection device consists of amplifier, filters, A/D converter and RF module. After amplification and filtering, the ECG signal is fed through the A/D converter to be digitalized. The digital ECG data is transmitted to the personal computer through the RF transceiver module and serial port.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.2
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• pp.155-162
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• 2009

In walking guide robot, a guide vehicle detects an obstacle distribution in the walking space using range sensors, and generates a 3D grid map to map the obstacle information and the tactile display. And the obstacle information is transferred to a blind pedestrian using tactile feedback. Based on the obstacle information a user plans a walking route and controls the guide vehicle. The algorithm for 3D detection of an obstacle distribution and the method of mapping the generated obstacle map and the tactile display device are proposed in this paper. The experiment for the 3D detection of an obstacle distribution using ultrasonic sensors is performed and estimated. The experimental system consisted of ultrasonic sensors and control system. In the experiment, the detection of fixed obstacles on the ground, the moving obstacle, and the detection of down-step are performed. The performance for the 3D detection of an obstacle distribution and space mapping is verified through the experiment.

• Publications of The Korean Astronomical Society
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• v.21 no.2
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• pp.95-100
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• 2006

In this paper, we describe the radio astronomical data processing system implementation using Mark5B and its development. KASI(Korea Astronomy and Space Science Institute) is constructing the KVN (Korean VLBI Network) until the end of 2007, which is the first VLBI(Very Long Baseline Interferometery) facility in Korea and dedicated for the mm-wave VLBI observation. KVN will adopt the DAS (Data Acquisition System) consisting of digital filter with various function and 1Gsps high-speed sampler to digitize the radio astronomical data for analyzing on the digital filter system. And the analyzed data will be recorded to recorder up to 1Gbps data rates. To test this, we have implemented the system which is able to process 1Gbps data rates and carried out the data recording experiment.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.2
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• pp.229-238
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• 2012

This study is to compare muscle strength between isotonic exercise and isotonic & isokinetic exercise. Participants are 12-man and 10-woman whom they are healthy without medical history in shoulder, elbow and lumbar joint. We performed experiment total 4-weeks that exercise 3-days a week each exercise pattern. We measured shoulder, elbow and lumbar joint torque with BIODEX and circumference of muscle in upper arms once a week. The result showed that isotonic & isokinetic exercise pattern significantly more improved joint torque in shoulder, elbow, lumbar than isotonic exercise pattern. Because that isotonic & isokinetic exercise pattern supplied muscle strengthen and caused muscle contraction. This exercise pattern can be used new exercise training method for major athlete and normal people. Also this pattern can be used rehabilitation treatment.