• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2146-2148
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• 2005

The 2.5GeV linac of the Pohang Light Source(PLS) is planed to be converted to a XFEL. The PAL XFEL requires a new 1.2-GeV linac that will be combined to the existing linac to increase a beam energy upto 3.7GeV. This stability is mainly determined by a low level RF drive system and klystron-modulators. The stability level of the modulator has to be improved 10 times better to meet the pulse stability of 0.02 %. The regulation methods such as traditional de-Qing and precision inverter charging technology are reviewed to find out suitable upgrade scheme of the modulators. In order to obtain electron beam of the consequently stability for XFEL linac, the pulse-to-pulse beam voltage regulation is less than +/-0.5%. To get the reliable stability of the modulator which is less than +/-0.2%, a charging section is improved in a modulator which has been operated with inverter power supply and de-Q'ing.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.330-339
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• 2008

Ground-based interceptors(GBI) comprise a major element of the strategic defense against hostile targets like Intercontinental Ballistic Missiles(ICBM) and reentry vehicles(RV) dispersed from them. An optimum design of the subsystems is required to increase the performance and reliability of these GBI. Propulsion subsystem design and optimization is the motivation for this effort. This paper describes an effort in which an entire GBI missile system, including a multi-stage solid rocket booster, is considered simultaneously in a Genetic Algorithm(GA) performance optimization process. Single goal, constrained optimization is performed. For specified payload and miss distance, time of flight, the most important component in the optimization process is the booster, for its takeoff weight, time of flight, or a combination of the two. The GBI is assumed to be a multistage missile that uses target location data provided by two ground based RF radar sensors and two low earth orbit(LEO) IR sensors. 3Dimensional model is developed for a multistage target with a boost phase acceleration profile that depends on total mass, propellant mass and the specific impulse in the gravity field. The monostatic radar cross section (RCS) data of a three stage ICBM is used. For preliminary design, GBI is assumed to have a fixed initial position from the target launch point and zero launch delay. GBI carries the Kill Vehicle(KV) to an optimal position in space to allow it to complete the intercept. The objective is to design and optimize the propulsion system for the GBI that will fulfill mission requirements and objectives. The KV weight and volume requirements are specified in the problem definition before the optimization is computed. We have considered only continuous design variables, while considering discrete variables as input. Though the number of stages should also be one of the design variables, however, in this paper it is fixed as three. The elite solution from GA is passed on to(Sequential Quadratic Programming) SQP as near optimal guess. The SQP then performs local convergence to identify the minimum mass of the GBI. The performance of the three staged GBI is validated using a ballistic missile intercept scenario modeled in Matlab/SIMULINK.

• Progress in Medical Physics
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• v.25 no.1
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• pp.1-7
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• 2014

Hyperthermia is effective treatment modality when it combine with the radiotherapy treatment. It is important to verify the temperature distribution of (patient's) body for the safety and effective treatment during raising the temperature. In this study, we raised the temperature in agar phantom using radio frequency (RF) Hyperthermia and protocol that manufacture recommend. Temperature distribution measured 5 section of 5 cm thickness with agar phantom. When the temperature was raised according to the increase energy. Temperature distribution was elevated at similar domain regardless of energy. The temperature tend to be increased at up side then bottom side and also increase when A large electrode was used than small one.

• Korean Journal of Oriental Medicine
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• v.12 no.1
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• pp.23-38
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• 2006

The taxonomic list of specific features in external and internal shape and the pattern analysis of Aconitum carmichalei $D_{EBX}$ as the original plant of Aconiti Lateralis Radix Preparata and Aconitum cliiare Dc as the original plant of Aconiti Ciliare Tuber are as follows. 1. Aconitum carmichalei $D_{EBX}$ has tri-palmately parted leaves, petiole in lower leaves, and its ovary has short hair. Whereas Aconitum cliare Dc has $3{\sim}4$ parted leaves, long petiole, and its ovary has not hair. 2. Aconitum carmichalei $D_{EBX}$ has cylinder shape is relatively small in length and diameter, is greyish brown blacky brown in outer surface, greyish $white{\sim}dark$ gray in section. 3. According to the collection place, there is a remarkable difference in the physical shape of herbal states. Aconiti Lateralis Radix Preparate(medicated in Korea) is more transparent blacky brown color than Aconiti Lateralis Fadix Preparata(medicated in Chian). Also Black Aconi Radix(墨附片) has exodermis and White Aconi Radix(白附片) has not. 4. The internal characteristics entirely correspond to in internal shape described in the literatures, Only it is possible to discriminate between black Aconi Radix(墨附片) and White Aconi Radix(白附片) by the existence of cork layer. The classification between Aconiti Lateralis Radix Preparata and Aconiti Ciliare Tuber makes entirely Tuber makes entirely remarkable difference in the physical shape of cambium layer Namely, in shape of cambium layer the kinds of Aconiti lateralis Radix Prepala has horn-like shape and the kinds of Aconiti Ciliare Tuber has circle-like shape. 5. In the peak of examination substance in comparison to Rt of the index material diterpene alkaloid mesaconitine, aconitine, hypaconitine chromatogram Aconiti Ciliare Tuber is higher than in Aconiti Lateralis Radix Preparata This explain that the component changes after the process of medicine. 6. In the Content of mesaconitine, aconitine and hypaconitime Aconiti Ciliare Tuber is higher than Aconiti Lateralis Radix Preparata. 7. In Aconiti Lateralis Radix Preparata, aconitine, hypaconitine and mesaconitine each appears in Rf 0.46, 0.54, 0.32. But except Aconiti Ciliare Tuber the band does not appear. For the future, such results will be used as the basic source of additional research, and a far-reaching comparative study is needed to distinguish between many kinds of same genus-degree of relatedness.