• Journal of Radiation Industry
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• v.17 no.1
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• pp.1-9
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• 2023

Since a large amount of radioactive waste is expected to be generated due to permanent shutdown of many nuclear power plants, it is necessary to prepare efficient management methods for radioactive waste. Therefore, there is a need for a based study to apply the In-Situ gamma spectrometry, which can simplify the measurement procedure. The purpose of this study is to analyze research cases of In-Situ gamma spectrometry and to analyze the sensitivity of measurement according to influencing factors on In-Situ gamma spectrometry. Research cases of five institutions, including the CERN and the Imperial College Reactor Centre (ICRC), were selected as the institutions to be investigated. Research on the In-Situ gamma spectrometry was conducted on the satisfaction of the acceptance criteria for radioactive waste and the analysis of residual radioactivity in the site. In-Situ Objective Counting System (ISOCS) was used as a major measuring device. Sampling and computer code were used to verify the analysis results. For evaluation of measuring sensitivity according to influencing factors on In-Situ gamma spectrometry, the thickness of the measurement target, the distance between the detector and the target, the angle of the collimator, and the contamination location were performed using ISOCS's Geometry Composer. In every case, based on 122 keV, the efficiency decreased as the energy increased in the high energy region, and the efficiency decreased as the energy decreased in the low energy region. As the target thickness increased, the efficiency decreased, and as the distance between target and detector increased, the efficiency decreased. As the distance between contamination and detector increased, the efficiency decreased, and as the angle of the collimator increased, the measurement efficiency increased. However, when simulating the measurement situation using Geometry Composer, the background is not considered, and the probability of incident in the background increases as the angle increases, so further research needs to be conducted in consideration of these. This study can be utilized when applying the In-Situ gamma spectrometry of radioactive waste clearance in the future.

• Journal of Radiation Protection and Research
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• v.26 no.3
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• pp.161-165
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• 2001

We have developed a position-sensitive proton recoil telescope (PSPRT) which employs a position-sensitive photomultiplier (PS-PMT) and a scintillator for both a radiator and a proton-detector. This system is expected to achieve high energy resolution under a large solid angle, because it enables to obtain the information not only on the proton energy but also the recoil angle from the position data for both detectors. The response of the PSPRT for 14.1 MeV mono-energetic neutrons was measured, and the PSPRT proved to be operating as expected.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.851-856
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• 2003

This paper proposes a single-mode Lamb-wave generation and detection system using a pulsed laser as a generator and an air-coupled transducer combined with the wavelet transform analysis, as the detector. The laser source with arrayed linear slits was used to generate Lamb-wave which is able to control the wavelength of Lamb-wave to be generated by changing the slits separation. An ari-coupled transducer was used to receive Lamb-wave, which can selectably receive a single mode of leaky Lamb wave by changing the oblique angle of transducer, since the leaky Lamb-wave has unique leaky-angle according to the mode. Also, the received signal was processed by wavelet transform for the analysis in domain of time-frequency. The theoretical dipersion curve and the experimetal result was compared to show good agreement.

• Journal of the Korean Electrochemical Society
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• v.7 no.2
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• pp.80-82
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• 2004

The a.c. technique is employed to evaluate electrochemical characteristics of Naphthalie-1,4,5,8-tetracarboxylic acid bisanilide (NTB). The measurements were carried out in dry and pure propionitrle (PCN) and acetonitrile(CAN) at the hanging mercury drop electrode [HMDE). An A.C. phase sensitive detector using computer controlled lock-in amplifier was employed. Primary goal of this report, was to establish on a firm the rare behavior of the phase angle associated with a.c. polarograms of the compound. Although, not an initial goal of this study, the electron transfer rate parameters attending the electroreduction of the compound under investigation were determined. This because the results shed some light on the electrokinetics in aprotic solvent which until recently negligible data were available. Experimental Results and comparison of data obtained are reported. The good precision of the method makes it suitable for studying electrochemical data with unusual behavior at electrodes in non aqueous media.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.5
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• pp.213-221
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• 2002

In order to improve the reliability of XLPE cables, it is necessary to find the useful diagnostic parameter according to long term aging. This paper described the change of partial discharge(PD) phase Properties of XLPE cable insulation with branch type electrical tree degradation. for long term aging. To understand the PD Properties with $\phi$ -q-n distributed shape of XLPE insulation, specimens were prepared by 22.9㎸ distribution cable and made in a type of block(16${\times}$16${\times}$3[mm]). Ogura needles having tip radius of l0${\mu}{\textrm}{m}$ were inserted into each block pieces. The measuring system was consisted of PD detector, digitizer for digital conversion, VXI system for signal processing. The PD properties of the specimens were measured from initiation of tree to breakdown and their characteristics were analyzed. We analyzed the relationship between electrical properties(PD Quantity, PD initiation angle, PD extinction angle, PD occurrence angle : (PD extinction angle - PD initiation angle)) and the normalized aging rate. We found PD parameter, PD initiation angle and occurrence angle, which are a useful diagnostic parameter in estimating the branch type electrical tree for XLPE insulation condition.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.8
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• pp.29-39
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• 2015

This paper describes a design and implementation of fuzzy-based algorithm for hand-shake state detection and error compensation in the mobile optical image stabilization(OIS) motion detector. Since the gyro sensor output of the OIS motion detector includes inherent error signals, accurate error correction is required for prompt hand-shake error compensation and stable hand-shake state detection. In this research with a little computation overhead of fuzzy-based algorithm, the hand-shake error compensation could be improved by quickly reducing the angle and phase error for the hand-shake frequencies. Further, stability of the OIS system could be enhanced by the hand-shake states of {Halt, Little vibrate, Big vibrate, Pan/Tilt}, classified by subdividing the hand-shake angle. The performance and stability of the proposed algorithm in OIS motion detector is quantitatively and qualitatively evaluated with the emulated hand-shaking of ${\pm}0.5^{\circ}$, ${\pm}0.8^{\circ}$ vibration and 2~12Hz frequency. In experiments, the average error compensation gain of 3.71dB is achieved with respect to the conventional BACF/DCF algorithm; and the four hand-shake states are detected in a stable manner.

• Textile Coloration and Finishing
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• v.14 no.3
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• pp.19-25
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• 2002

Silk/cotton fabrics were treated with butanetetracarboxylic acid(BTCA) under various treating conditions such as concentration, treated time and curing temperatures. Bending property, tensile strength, wrinkle recovery angle, and shrinkage were measured. The BTCA concentration in the saponfication mixture was measured by an isocratic HPLC equipped with the strong cationic exchange column Aminex HPX-87-H and a UV detector. The detected concentration of BTCA was shown in silk side much more than that of cotton side. The bending and shrinkage properties were improved at minimum curing condition and the lower concentration of BTCA. Tensile strength decreased with increasing concentration of BTCA, curing temperature and treated time, while wrinkle recovery angle increased.

• Journal of the Korean Society of Radiology
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• v.13 no.1
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• pp.141-146
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• 2019

Radiation sources used in the field of industrial non-destructive pose a risk of exposure due to ageing equipment and operator carelessness. Thus, the need for a safety management system to trace the location of the source is being added. In this study, Monte Carlo Simulation was performed to analyse the angle dependence of the unit-cell comprising the line-array dosimeter for tracking the location of radiation sources. As a result, the margin of error for the top 10% of each slope was 5.90% at $0^{\circ}$, 8.08% at $30^{\circ}$, and 20.90% at $60^{\circ}$. The ratio of the total absorbed dose was 83.77% at $30^{\circ}$ and 53.36% at $60^{\circ}$ based on $0^{\circ}$(100%) and showed a tendency to decrease with increasing slope. For all gradients, the maximum number was shown at $30^{\circ}$ No. 9 pixels, and for No. 10, there was a tendency to drop 7.24 percent. This study has shown a large amount of angle dependence, and it is estimated that the proper distance between the source and line-array dosimeters should be maintained at a distance of not less than 1 cm to reduce them.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.3
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• pp.737-746
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• 1996

In this paper, we present simulation result of quantization effects about a new Angular From Carrier Recovery Loop(AF CR loop) for PSK modulation technique. AF CR loop includes detected angle symbol and Multi Level hardimiter. In general, detected angle is used in dtermining symbol. Because detected angle is used to make an error signal of phase detector output, hardware implementation of AF CR loop is simpler than that of other loops. Before hardware implementation of AF CR loop, the result due to quantization effect should be investigated. In order to confirm quntization effect of AF CR loop, we evaluate performance of this loop by Monte-Carlosimulation method. Under both in the AWGN and Jake's fading noise channel environments, we confirmed the characteristics of AF CR loop in terms of RMS jitter due to quntization effect. Differential APSK modulation schemeis used in this paper. Especially, Jake's fading channel is used as a channel model and also AGC(Automatic Gain Control) is used in the overall process of performance evaluation. We obtained the resonable result of quantization effect about AF CR loop. With the result of performanceevaluation based on quantization effects, we can expect to operate AF CRloop under the fading channel environments reasonably well.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.107.1-107.1
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• 2014

We have developed and commercialize a time-of-flight - medium energy ion scattering spectrometry (TOF-MEIS) system (model MEIS-K120). MEIS-K120 adapted a large solid acceptance angle detector that results in high collection efficiency, minimized ion beam damage while maintaining a similar energy resolution. In addition, TOF analyzer regards neutrals same to ions which removes the ion neutralization problems in absolute quantitative analysis. A TOF-MEIS system achieves $7{\times}10^{-3}$ energy resolution by utilizing a pulsed ion beam with a pulse width 350 ps and a TOF delay-line-detector with a time resolution of about 85 ps. TOF-MEIS spectra were obtained using 100 keV $He^+$ ions with an ion beam diameter of $10{\mu}m$ with ion dose $1{\times}10^{16}$ in ordinary experimental condition. Among TOF-MEIS applications, we report the quantitative compositional profiling of 3~5 nm CdSe/ZnS QDs, As depth profile and substitutional As ratio of As implanted/annealed Si, Ionic Critical Dimension (CD) for FinFET, Direct Recoil (DR) analysis of hydrogen in diamond like carbon (DLC) and InxGayZnzOn on glass substrate.