• The Journal of Korean Society for Radiation Therapy
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• v.5 no.1
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• pp.47-56
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• 1992

This report presents the date obtained in a 1990 survery al radiation oncology identified by KSTRO. This study was done to find out the status of current use of the radation thrapy equipments, personnels, utilization of equipments and orther problems in the field of radiation oncology department in korea. Our discussion addresses the areas of regional imbalance in the distribution of megavolage units, buying and selecting the units, improving of quality in radiation treatments. There is increasing use of linear accelerators, simulators, treatment planning computers. The use of Cp-60 units has been prohressively decreasing. And slowly improving, numbers of physicians, physicists, and technologists when compared with the 1988. A total of 51 megavoltage units were identified, giving a ratio of 1.88 technologists/ megavoltage units. We treat average 23.0 patients by megavoltage units.

• Journal of IKEEE
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• v.22 no.1
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• pp.197-200
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• 2018

In this paper, sigmoid function, which is difficult to implement at hardware level and has a slow speed, is approximated by using PLAN. We use this as an activation function of MLP structure to reduce resource consumption and speed up. In this paper, we show that the proposed method maintains 95% accuracy in $5{\times}5$ size recognition and 1.83 times faster than GPGPU. We have found that even with similar resources as MLPA accelerators, we use more neurons and converge at higher accuracy and higher speed.

• Journal of The Korean Astronomical Society
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• v.37 no.5
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• pp.465-470
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• 2004

I address the issue of nonthermal processes in the large scale structure of the universe. After reviewing the properties of cosmic shocks and their role as particle accelerators, I discuss the main observational results, from radio to $\gamma$-ray and describe the processes that are thought be responsible for the observed nonthermal emissions. Finally, I emphasize the important role of $\gamma$-ray astronomy for the progress in the field. Non detections at these photon energies have already allowed us important conclusions. Future observations will tell us more about the physics of the intracluster medium, shocks dissipation and CR acceleration.

• Proceedings of the KIEE Conference
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• 1997.07f
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• pp.2252-2254
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• 1997

There are increasing demands on high accruacy DC power supplies for varous basic science reseach, such as accelerators and plasma applications, in Korea. In this paper, we present a study on 1kW class DC power supply using the parell operation method of the flyback converters. This DC power supply is equipped with a remote controller for computer interface. A Serial Communication Controller(SCC) is also developed for large scale scientific facilities which is capable of handling upto 32 power supplies simultaneously with one serial port in the host computer.

• Journal of the Korean Ceramic Society
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• v.35 no.9
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• pp.933-938
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• 1998

The hydration for the system of fluorogypsum and 20wt% blast furnace slag was investigated at liquid/soild ratio of 0.45 for 1, 3, and 7 days by using 3 kinds of accelerators such as K2SO4 Al2(SO4)3 $.$16-18H2O and AlK(SO4)2$.$12H2O After curing the hardened specimen was characterized by the compressive strength the content of combined water XRD, DTA and SEM It was found that the activating effect was increased in the order of K2SO4

• BMB Reports
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• v.36 no.1
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• pp.60-65
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• 2003

Cancer is frequently considered to be a disease of the cell cycle. As such, it is not surprising that the deregulation of the cell cycle is one of the most frequent alterations during tumor development. Cell cycle progression is a highly-ordered and tightly-regulated process that involves multiple checkpoints that assess extracellular growth signals, cell size, and DNA integrity. Cyclin-dependent kinases (CDKs) and their cyclin partners are positive regulators of accelerators that induce cell cycle progression; whereas, cyclin-dependent kinase inhibitors (CKIs) that act as brakes to stop cell cycle progression in response to regulatory signals are important negative regulators. Cancer originates from the abnormal expression of activation of positive regulators and functional suppression of negative regulators. Therefore, understanding the molecular mechanisms of the deregulation of cell cycle progression in cancer can provide important insights into how normal cells become tumorigenic, as well as how cancer treatment strategies can be designed.

• Elastomers and Composites
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• v.22 no.4
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• pp.333-339
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• 1987

A modern kinetic evaluation method for nonisothermal reactions measured with Differential Scanning Calorimetry(DSC) is presented. It is based on multiple linear regression analysis using a number of curve points in a selectable range of conversion. The obtained kinetic data are the basis to compute a reaction process under any condition e.g. isothermal or adiabatic. The DSC measurements was performed on a Mettler TA3000 SYSTEM with the built in evaluation software. Mainly the following reactions are discussed: vulcanization of natural rubber compounds containing vulcanizing accelerators. The purpose of this work is to analyse the vulcanization kinetics of typical NR vulcanization systems using DSC. These systems were chosen because they are typically reactive elastomer and are commercially important.

• Journal of Sericultural and Entomological Science
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• v.16 no.2
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• pp.127-131
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• 1974

Although several kinds of repellents or attractants have been used for mounting accelerators in the silkworm. Bembyx mori, more effective reagents still have not been developed. The authors developed a mounting accelerator with medical herb (Achyranthes bidentata Blume) and glutamic acid, an indispensable amino acid of silkworm, and experimented it's effects in both periods of spring and fall in 1972-1973. It was obtained that the mounting accelerator newly developed by authors shortened the economic periods by a half day, and did not have an bad effect on cocoon quality.

• World Technopolis Review
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• v.1 no.1
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• pp.27-41
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• 2012

The science and technology park movement has been developing for over 60 years. The first developments simply relied on the co-location of tenant companies and the park's host to encourage technology transfer. This is in contrast with their modern counter parts which offer a range of active links between tenant companies and host organisations as well as a raft of business development services to support technology commercialisation. Many of these sites have also become important centres in regional innovation plans. In these cases they are supported by a range of local, regional and national policies that are aimed at establishing a business, technology and social environment which support innovation. The paper examines both the business development programmes developed by science and technology parks to support technology commercialisation and the macro conditions that are now being developed to support innovation.

• The Journal of Korean Society for Radiation Therapy
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• v.14 no.1
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• pp.109-116
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• 2002

The mordem linear accelerators are equipped with X-ray collimators that can be moved independently to allow asymmetric fields with field centers positioned away from the true central axis of the beam. We have studied the dosimetric of an independent collimator system using measurements performed quarter fields. The field size factors for asymmetric fields are compared to those for symmetric fields. Dosimetric measurements include portent depth don, beam penumbra and shape of isodose curves for symmetric and quarter fields.