• Journal of The Korean Astronomical Society
• /
• v.37 no.3
• /
• pp.119-129
• /
• 2004

A new method has been developed to solve the star cluster membership problem. It is based on synthetic photometry employing the Black Body concept as stellar radiation simulator. Synthetic color-magnitude diagram is constructed showing the main sequence band and the positions of binary star systems of combinations of various components through different photometric tracks. The method has been applied to the Hyades. The cluster membership problem has been re-appraised for the cluster (both single and binary) stars. For the binary members, the components' spectral types have been derived by the method. The results obtained agree very well with those found in literature, The method is simpler than the others and can be developed to undertake other cases as multiple star systems.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.16 no.5
• /
• pp.435-440
• /
• 2003

The electron-atom collision studies have been essentially used for testing and developing suitable theories of the scattering and collision processes, and for providing a tool for obtaining detailed information on the structure of the target atoms and molecules and final collision products. And, the development of that has also been strongly motivated by the need for electron collision data in such fields as laser Physics and development, astrophysics, Plasma devices, upper atmospheric processes and radiation physics. The concept and the Principle of determination of the electron collision cross sections for atoms and molecules by using the present electron swarm method are explained.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.18 no.1
• /
• pp.212-222
• /
• 1994

In the annular Modified Chemical Vapor Deposition process using two concentric tubes, the inner tube is heated to maintain high temperature gradients to have high thermophoretic force which can increase particle deposition efficiency. However, higher axial velocity in a narrow gap between inner and outer tubes can result in a longer tapered entry length. In the present paper, a new concept using an annular jet from the inner tube is presented and shown to significantly reduce the tapered entry length with maintaining high efficiency. Effects of a jet injection on heat transfer, fluid flow and particle deposition have been studied. Of particular interests are the effects of jet velocity, jet location and temperature on the deposition efficiency and tapered length . Torch heating effects from both the previous and present passes are included and the effect of surface radiation between inner and outer tubes is also considered.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 1997.11a
• /
• pp.260-268
• /
• 1997

The safety of LPG vessel storage has been simply designed and controled with blast wave barrier structure concept regardless of its quantity or hazardous situation. The limit of regal controls on LPG vessel storage need to be identified in terms of safety buffer distance from LPG explosion. The level of overpressure effect and heat radiation In the safety structure and neighbouring human activity required to be estimated to find the gap between existing controls on such storage. To this content the paper discuss the issues on the approach In the blast wave barrier and safety separation distances.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.08a
• /
• pp.431-431
• /
• 2012

A compact tokamak reactor concept as a 14 MeV neutron source is desirable from an economic viewpoint for a fusion-driven transmutation reactor. LAR (Low Aspect Ratio) tokamak allows a potential of high "see full txt" operation with high bootstrap current fractions and can be used for a compact fusion neutron source. For the optimal design of a reactor, a radial build of reactor components has to be determined by considering the plasma physics and engineering constraints which inter-relate various reactor components and are constrained to use ITER physics and technology. In a transmutation reactor, the blanket should produce enough tritium for tritium self-sufficiency and the neutron multiplication factor, keff should be less than 0.95 to maintain sub-criticality. The shield should provide sufficient protection for the superconducting toroidal field (TF) coil against radiation damage and heating effects of the fusion neutrons, fission neutrons, and secondary gammas. In this work, characteristics of transmutation reactor based on LAR tokamak is investigated by using the coupled system analysis.

• Nuclear Engineering and Technology
• /
• v.31 no.3
• /
• pp.276-286
• /
• 1999

A computer code PARS2 is developed for the analysis of PSDRS, which is the safety grade RHRS of HAMMER, and applied to the investigation of the relation between design parameters and performance of PSDRS. The concept of the heat transfer resistance network is applied in assessing the importance of the various heat transfer modes. From the analysis results, the qualitative relations between the PSDRS performance and design parameters are found and guidelines for the PSDRS design procedures are also proposed.

• 한국연소학회:학술대회논문집
• /
• 2003.12a
• /
• pp.3-9
• /
• 2003

By utilizing a semi-empirical soot model, the applicability of the laminar flamelet concept for simulating the formation and oxidation of soot in the laminar diffusion flame has been studied. The source terms for two transport equations of the soot formation and oxidation are calculated in the mixture fraction/scalar dissipation rate space for laminar flamelets and stored in a library. In this study, emphasis is given to the interaction associated with radiation and soot formation. The radiative heat loss is obtained by solving the radiative transfer equation using the unstructured grid finite volume method with the WSGGM. The calculated temperatures and soot volume fractions agree relatively well with the experimental data and the previous numerical results of Kaplan et al. using the detailed chemistry.

• Journal of electromagnetic engineering and science
• /
• v.13 no.4
• /
• pp.208-213
• /
• 2013

This paper proposes a tag antenna for radio frequency identification (RFID) food system. The RFID tag antenna is designed and fabricated based on the rectangular loop concept used in the UHF band (Korean and Japanese standards, 916.7-923.5MHz). The proposed tag antenna is composed of a radiation patch, sensor tag chip, temperature sensor, oscillator, and battery. We conjugated matching between the tag antenna and the sensor tag using a U-shaped stub. Details of the proposed tag antenna design and the simulated and measured results are presented and discussed.

• Nuclear Medicine and Molecular Imaging
• /
• v.41 no.6
• /
• pp.525-529
• /
• 2007

Regulation for the radiopharmaceuticals should be reasonably different from that of other drugs. Radiopharmaceuticals are always used by compounding based on the doctor's order, have short half life and very low administration dose. Its pharmacological effect is not from its chemical effect but from radiation. The background for exploratory IND (Investigational New Drug) explained by the FDA was to reduce the time and resources expended on candidate products that are unlikely to suceed, new tools are needed to distinguish earlier in the process those candidates that hold promise from those that do not. In this review, basic concept for exploratory IND and RDRC guideline is summarized and various suggestions for improving and expediting procedure for new radiopharmaceutical development would be described.

• ETRI Journal
• /
• v.35 no.6
• /
• pp.1075-1083
• /
• 2013

This paper describes an ultra-wideband (UWB) antenna that uses a ring resonator concept. The proposed antenna can operate in the entire UWB, and the IEEE 802.11a frequency band can be rejected by inserting a notch stub into the ring resonator. The experiment results indicate that the measured impedance bandwidth of the proposed antenna is 17.5 GHz (2.5 GHz to at least 20 GHz). The proposed UWB antenna has omnidirectional radiation patterns with a gain variation of 3 dBi (1 dBi to 4 dBi).