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[en] The research activities of Korea Cancer Center Hospital have increased for the past a few years just in proportion to the increase of research budget, but the assisting manpower of the office of research management has never been increased and the indications are that the internal and external circumstances will not allow the recruitment for a fairly long time. It has, therefore, become inevitable to enhance the work efficiency of the office by analyzing the administrative research assistance system, finding out problems and inefficiency factors, and suggesting possible answers to them. The office of research management and international cooperation has conducted this research to suggest possible ways to facilitate the administrative support for the research activities of Korea Cancer Center Hospital By analyzing the change of research budget, organization of the division of research and administrative support, manpower, and the administrative research supporting system of other institutes, we suggested possible ways to enhance the work efficiency for administrative research support and developed a relative database program. The research report will serve as a data for the organization of research support division when the Radiation Medicine Research Center is established. The database program has already been used for research budget management
[en] This project is to conduct a study on the characteristics of radioactive waste expected to arise from 4 potential types of nuclear fuel cycles being considered for future nuclear power generation, so that the outcome of the study can serve as a basis for the development of technology on radioactive waste treatment and disposal, at the stage when the government makes a decision to take one of the future nuclear fuel cycle options. The above mentioned study is necessary because safe and effective management of future radioactive waste requires basic and in-depth information in particular regarding chemical properties for the treatment and disposal, which can be chosen based on such study, have their own strength and weakness requiring R and D to find an optimized solution to the specific nuclear duel cycle and nuclear policy pursued by a country.
[en] P-compound of 10mol%(about 7.8wt%) embedded CaSO4:Dy TL pellet(KCT-300) was developed by KAERI. KCT-300 has high sensitivity and good dosimetric characteristics than Teflon embedded CaSO4:Dy TL pellet. But, mechanical strength of KCT-300 is not good. Essentially the mechanical strength is improved with increased the P-compounds concentration, but TL sensitivity is decreased relatively. In the case of high P-compounds concentration, surface of KCT-300 is rugged after sintering. So, it is too difficult that improve the mechanical strength of KCT-300 as raise P-compounds concentrate. This paper presented the method for raise mechanical strength of KCT-300. In this research, high temperature treatment process after P-compounds embedded CaSO4:Dy TL phosphor added to fabrication process of KCT-300
[en] The effect of the filament heating condition to the arc discharge characteristics of the KSTAR NBI ion source has been studied. Are discharge current is increased by FIC(Filament Initial Current) and the uniformity of the are current after are discharge is affected by FCR(Filament Current During Arc). Under the 40 sccm of hydrogen gas flow and 80 V of are voltage, the optimum filament heating conditions are 3300 A∼3400 A of FIC and 2850 A∼2900 A of FCR. The optimum operation mode of the power supplies has been studied. The optimum operation mode of the are power supply is CP(Constan Power) mode because the ion saturation current of Langmuir probe is increased with are power
[en] Personal neutron dosimetry is quite a difficult area because a neutron is always accompanied with gamma radiation, which is required of a the capability for mixed field dosimetry. CaSO4: Dy phosphor is known to have a very high sensitivity to gamma, but the neutron capture cross section of the constituents of CaSO4:Dy are so small that the interactions between the thermal neutron and the phosphor are rare. One method to improve the neutron interaction is by introducing an impurity ion with a large thermal neutron captures cross section into the phosphor to act as a neutron target centre such as 6Li. In neutron-gamma mixed radiation fields, if two detectors for the 6Li-7Li compounds embedded CaSO4:Dy TL pellets are used, a 6Li-compound embedded pellet can detect the neutron and gamma radiation together, and the other pellet can only detect the gamma radiation. Recently Korea Atomic Energy Research Institute (KEARI) has developed a new type of CaSO4:Dy TL materials embedded with phosphorous (KCT-300) to detect beta and gamma radiation with a very high sensitivity. This paper presents the development of CaSO4:Dy TL pellets embedded with 6Li compound for a thermal neutron measurement, and the detection method of the neutron and gamma dose in mixed fields with CaSO4:Dy TL pellets embedded with a 6Li compound(KCT-306) and CaSO4:Dy TL pellets embedded with a 7Li compound(KCT-307) is introduced. The net neutron sensitivity of CaSO4:Dy TL pellets embedded with 6Li compound developed in this study is about 2 times higher than that of the TLD-600 (Harshaw Co.) dosimeter which is available in the open market
[en] Chitosan is a polysaccharide of natural origin obtained by full or partial deacetylation of chitin, a very abundant natural polymer, which has the properties of biocompatibilities, bioaffinities, and biodegradabilities. The free amino group of chitosan should be participated in forming chelate with holmium (β-emitter). Ho-166(NO3)3. 5H2O of high radionuclidic purity of up to 99.9% was made by neutron irradiation of naturally occurring Ho-165(NO3)3., 5H2O, and then reacted with the prepared chitosan solution. The effect of pH, reaction time, the concentration and viscosity of chitosan and the amount of Ho-166 on forming Ho-166-chitosan complex (Ho-166-CHICO) were investigated. Ho-166-chitosan macroaggregate(Ho-166-CHIMA) was made from Ho-166-CHICO. Their physical properties such as radionuclidic purity, particle size distribution, stability in vitro and vivo were examined. Their high in vitro and vive stability makes them attractive agents for internal radiotherapy by local administration.
[en] ATLAS test facility, which is an integral test loop for simulation of various thermal hydraulic phenomena in APR1400 (Advanced Power Reactor 1400 MWe), has been designed according to the three-level scaling method. Scaling ratio of the facility is 1/2 in length and 1/144 in area. To make the experimental data in the ATLAS scaled up reasonably, it is necessary to validate the scaling methodology and the design characteristics of the ATLAS by performing a counterpart test and comparing a reference test data. In this study, a Small-Break Loss-of-Coolant Accident (SBLOCA) scenario was selected for the counterpart test in the ATLAS. The reference test data could be found from SB-CL-32 test in LSTF (Large Scale Test Facility), which simulated 1% cold leg SBLOCA in the full-height integral test loop. In prior to conduct the experiment, appropriate test condition was defined considering the scaling methodology and design parameter of the ATLAS. To validate the counterpart test condition in the ATLAS, MARS-KS code calculation result was compared to the LSTF test data. To validate the scaling methodology and the design parameter of the ATLAS test facility, the counterpart test condition was determined for the cold leg SBLOCA simulation. The initial and boundary conditions in SB-CL-32 test data of the LSTF were scaled down according to the scaling methodology, so that the test condition in the Atlas was obtained. In prior to the experiment, Mars-KS code simulated the steady state and transient in the ATLAS test facility. The code calculation result proved that the counterpart test in the ATLAS could preserve the transient behavior in the reactor coolant system during the SBLOCA. Major events such as the pressure plateau and excursion of the maximum cladding temperature showed a good agreement with the LSTF test data. In the further work, the experiment for the counterpart test will be performed and scaling effect in the ATLAS test data can be analyzed in detail by comparing the result to the LSTF test data
[en] The dosimetric properties of the newly developed LiF:Mg,Cu,Na,Si TL detector was investigated by using the method which was presented in IEC 1066 international standard 'Thermoluminescence dosimetry systems for personal and environmental monitoring'. The sensitivity of the TL detector was about 30 times higher than that of TLD-100 by the light integration. In the study of dose linearity of the detector, the dose response was very linear up to 10 Gy and 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 results showed 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 10 detectors collectively was 0.0054. IEC standard requires that the coefficient of variation shall not exceed 0.0075. So, the reproducibility of this new TL detector sufficiently satisfied the IEC requirements. Lower limit of detection of the detector was investigated as 70 nGy by Harshaw 4500 TLD reader
[en] The resonance fluorescence from weakly excited two level atoms confined in a sub wavelength region (Lamb Dicke regime)shows Dicke narrowing and vibrational Raman sidebands. We have measured the resonance fluorescence spectrum of a few rubidium atoms trapped in optical micro potentials formed in a phase stabilized magneto optical trap by using the photon counting based second order correlation spectroscopy(PCSOCS). In our experiment the second order correlation function g"2"ℎ(τ)of the heterodyne signal obtained by mixing the resonance fluorescence from the atoms and a weak local oscillator was measured by PCSOCS method. The first order coherence of the resonance fluorescence contained in g"2"ℎ(τ)was Fourier transformed to reveal the resonance fluorescence spectrum. The spectrum shows a narrow central peak and small sidebands corresponding to Dicke narrowing and vibrational levels and oscillation frequency in the micro potential were obtained. Combined with our atom number feedback technique, by which the number of trapped atoms was precisely controlled, we could measure the resonance fluorescence spectrum of a single rubidium atom localized in a micro potential. In addition, we calculated the 3 dimensional structure of micro potential and its energy band structure, which explains the observed linewidths