• Journal of radiological science and technology
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• v.21 no.2
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• pp.53-56
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• 1998

Highly sensitive $CaSO_4:Tm$ TLD is fabricated and their trap parameters are determined. The glow curve of $CaSO_4:Tm$ consists of three glow peaks and these peaks are isolated by the thermal bleaching method. The isolated glow peaks are fitted by a least squares method. The activation energies are 0.68, 0.82 and 1.03 eV. The frequency factors are $8.09{\times}10^8,\;9.14{\times}10^8$ and $1.03{\times}10^9/s$, and the kinetic orders are 1.37, 1.54 and 1.68, respectively. The optimum temperature range of the main peak for radiation dosimetry is between 220 and $290^{\circ}C$.

• Structural Engineering and Mechanics
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• v.60 no.1
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• pp.131-148
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• 2016

Tuned Liquid Dampers (TLDs) provide low damping when it comes to deep water condition, and that not all water depth is mobilized in energy dissipation. This research focussed on a method to improve the efficiency of TLDs with deep water condition. Several bottom-mounted baffles were installed inside a TLD and the dynamic characteristics of modified TLDs together with their effect on the vibration control of a SDOF structure were studied experimentally. A series of free vibration and harmonic forced vibration tests were carried out. The controlling parameter in the conducted tests was the Vertical Blocking Ratio (VBR) of baffles. Results indicated that increase in VBR decreases the natural frequency of TLD and increases its damping ratio. It was found that the VBR range of 10% to 30% reduced response of the structure significantly. The modified TLD with the VBR of 30% showed the best performance when reduction in structural responses under harmonic excitations were compared.

• Proceedings of the Korean Information Science Society Conference
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• 2006.10d
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• pp.571-575
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• 2006

통일에 대비한 남북한 인터넷 통합을 위한 준비작업으로서 통일 국가도메인 제정에 대한 논의가 계속되어 왔다. 분단상태의 남북한이 국가 도메인을 하나로 통합하여 공동으로 사용한다는 상징성이 크다는 점에서 남북한 모두가 동의할 수 있는 도메인을 제정하는 일은 중요하다. 통일 국가도메인에 대한 기존 제안들은 우리나라의 현 영문 국호인 'Korea'를 전제로 한 것들이었다. 논자는 일제 강점기 이전까지 우리 나라 영문 국호로 'Corea'가 사용되었다는 주장에 근거한 국호 영문표기 변경 논의가 남북 학술대회와 국회 결의안 등을 통해 공론화되어 많은 호응을 얻고 있음에 주목하였고, 남북한 국호의 영문표기 변경 논의와 연계하여 통일 국가도메인 제정을 추진하는 것이 시의적절하고 효율성도 높다고 판단하였다. 본 논문에서는 통일국가 도메인에 대한 기존 논의들을 검토하고 유사국가들의 국가도메인(ccTLD) 등록 사례를 통해 통일 국가도메인의 등록 가능성을 탐색한 후 통일 국가도메인명으로서 '.uc'(United Corea)를 최종 제안하였다.

• Radiation Oncology Journal
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• v.12 no.2
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• pp.263-267
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• 1994

In clinical radiotherapy, the use of wide and irregular field techniques frequently results in considerable tumor dose inhomogeneity because of, the variation in physical characteristics of irradiated volumes. This report describes an analysis of the dosimetry of the irregular fields such as radiation fields for Hodgkin's disease(mantle field), esophageal cancer, and lung cancer when a 6 MV and a 15 MV linear accelerators are utilized. Doses were measured in a Rando phantom using methods of thermoluminescence dosimetry(TLD), and were calculated by radiotherapy planning computer system with the Clarkson's method for calculation of a irregular field. A dose variation of $5-22\%,\;6-9\%,\;6-14\%$ were found in the mantle field, esophageal cancer field, lung cancer field respectively. Higher doses occurred in the superior portion of the irregular field. The sites of maximum dose variation were the supraclavicular and the upper spinal cord region. To adjust for these substantial differences, a compensator or a shrinking field technique should be adopted.

• The Journal of Korean Society for Radiation Therapy
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• v.7 no.1
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• pp.92-96
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• 1995

All patients who will Undergo irraidiation of the oral cavity cancer will need dental before and during Radiotherapy. The extent of the region and the presence of numerous critical normal tissues(mucosa, gingiva, teeth and the alveolar ridge, alveolar bony structure, etc) in the oral cavity area, injury to which could result in serious functional impairment. Therefore I evaluate the Usefulness of custom-made intraoral shielding device before and during Radiotherapy in oral cavity cancer. Materials and Methods(1) : Manufacture process of Custom-made intraoral shielding device Containing Cerroband. A. Acquisition of impression B. Matrix Constitution C. Separation by Separator D. Sprincle on method E. Trimming F. Spacing G. Fill with Cerroband Materials and Methods (2) A. Preannealing B. TLD Set up C. Annealing D. TLD Reading = Results = Therefore dosimetric characteristics in oral cavity by TLD Compared to isodose curve dose distribution Ipsilateral oral mucosa, Contralateral oral mucosa, alveolar ridge, tongue, dose was reduced by intraoral shielding device containning Cerroband technique Compard to isodose plan = Conclusions = The custom-made intra-oral shielding device containing Cerroband was useful in reducing the Contralateral oral mucosa dose and Volume irradiated.

• Structural Engineering and Mechanics
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• v.41 no.1
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• pp.1-24
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• 2012

A reinforced concrete (RC) framed structure detailed according to non-seismic detailing provisions as per Indian Standard was tested on shake table under dynamic loads. The structure had 3 main storeys and an additional storey to simulate the footing to plinth level. In plan the structure was symmetric with 2 bays in each direction. In order to optimize the information obtained from the tests, tests were planned in three different stages. In the first stage, tests were done with masonry infill panels in one direction to obtain information on the stiffness increase due to addition of infill panels. In second stage, the infills were removed and tests were conducted on the structure without and with tuned liquid dampers (TLD) on the roof of the structure to investigate the effect of TLD on seismic response of the structure. In the third stage, tests were conducted on bare frame structure under biaxial time histories with gradually increasing peak ground acceleration (PGA) till failure. The simulated earthquakes represented low, moderate and severe seismic ground motions. The effects of masonry infill panels on dynamic characteristics of the structure, effectiveness of TLD in reducing the seismic response of structure and the failure patterns of non-seismically detailed structures, are clearly brought out. Details of design and similitude are also discussed.

• Journal of Radiation Protection and Research
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• v.17 no.2
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• pp.1-13
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• 1992

The purpose of this study is to develop an algorithm of TLD dose evaluation to meet all requirements stated in ANSI N13. 11-1983. It made the PB-3 TLD of Teledyne Isotopes an object of the development. Personal dosimetry performance testings of the development algorithm have been performed twice through the Atlan-Tech, INC. in accordance with the criteria of testing described in ANSI N13. 11-1983. As ,a result, it is assured that the developed algorithm has complied with all requirements stated in ANSI N13. 11-1983.

• Nuclear Engineering and Technology
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• v.36 no.1
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• pp.47-52
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• 2004

Recently, a new sintered pellet-type LiF:Mg,Cu,Na,Si TL detector which has a high sensitivity and good reusability, named KLT-300(KAERI LiF:Mg,Cu,Na,Si TL detector), was developed by the variation of the dopants concentrations and the parameters of the preparation procedure at KAERI (Korea Atomic Energy Research Institute). In this study, the thermoluminescent characteristics of the newly developed TL detectors were investigated. The sensitivity of the TL detector was compared with that of the TLD-100 by light integration. The dose linearity of the detector was tested from $10^{-6}$ Gy up to 30 Gy. The dose response was very linear up to 10 Gy and a sublinear response was observed at higher doses. The energy response of the detector was studied for photon energies from 20 keV to 662 keV. The result shows that a maximum response of 1.004 at 53 keV and a minimum response of 0.825 at 20 keV were observed. The reproducibility study for the TL detector was also carried out. The coefficients of variation for each detector separately did not exceed 0.016, and for all the 10 detectors collectively was 0.0054. Lower limit of detection for the detector was investigated at 70 nGy by the Harshaw 4500 TLD Reader and the residual signal of the TL detector was found to be $0.57\%$.

• Smart Structures and Systems
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• v.33 no.1
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• pp.27-39
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• 2024

The effectiveness of conventional tuned liquid dampers (TLDs) in controlling the wind-induced response of tall flexible structures has been indicated. However, the impaired control effect in the detuning condition or a considerably high mass cost of liquid may be incurred in ensuring the high-level serviceability. To provide an efficient TLD-based solution for wind-induced vibration control, this study proposes a serviceability-oriented optimal design method for isolated TLDs (ILDs) and derives analytical design formulae. The ILD is implemented by mounting the TLD on the linear isolators. Stochastic response analysis is performed for the ILD-equipped structure subjected to stochastic wind and white noise, and the results are considered to derive the closed-form responses. Correspondingly, an extensive parametric analysis is conducted to clarify a serviceability-oriented optimal design framework by incorporating the comfort demand. The obtained results show that the high-level serviceability demand can be satisfied by the ILD based on the proposed optimal design framework. Analytical design formulae can be preliminarily adopted to ensure the target serviceability demand while enhancing the structural displacement performance to increase the safety level. Compared with conventional TLD systems, the ILD exhibits higher effectiveness and a larger frequency bandwidth for wind-induced vibration control at a small mass ratio.

• Nuclear Engineering and Technology
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• v.56 no.2
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• pp.753-761
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• 2024

Introduction: In this study, TLD 600 and TLD 700 pairs were used to measure the neutron dose of Elekta Precise medical linac. To this end, the optimum moderate thickness for the conversion of fast to thermal neutrons were evaluated. Materials and methods: ²⁴¹Am-Be and ²⁵²Cf sources were simulated to calculate the optimum thicknesses of the moderator for the conversion of maximum fast neutrons (FN) into thermal neutrons (TN). Pair TLDs were used to measure F&TN doses for three different field sizes at four depths of the medical linac. Results: The maximum thickness of the moderator was optimized at 6 cm. The measurement results demonstrated that the TN dose increased with the expansion of field size and depth. The FN dose, which was converted TN, exhibits behaviors comparable to the TN due to its nature. Conclusion: This study presents the optimum thickness for the moderator to convert FN into TN and measure F&TN using TLDs.