• Journal of Life Science
• /
• v.11 no.5
• /
• pp.496-501
• /
• 2001

This study was carried out to investigate the cultural characteristics and the genetic characteristics in Lepists nuda. The mycelia cultural characteristics which include the specificity for pH, carbon source, nitrogen source and medium were studied using petridish culture and liquid media culture respectively. The genetic characteristics were also investigated using random amplified polymorphic DNA (RAPD) analysis. To find out the mycelial growth rate by various medium, mycelia was cultured for 25 days in PDA, YM, MEA, GPB and Yamanaka. The Yamanaka was superior to the other media in supporting the mycelial growth. pH6 produced the best result in the test of an optimal pH. In experiment for optimal carbon source, starch showa 46.8$\pm$1.7mm of diameter of mycelial colony as the best and for nitrogen source, yeast extract showed a good effect as well. In investigation for genetic characteristics, Lepists nuda was amplified by 7 primers among 10 primers and Pleurotus ostreatus was also amplified by 7 primers. From the RAPD analysis between species, the band patterns were different.

• Journal of The Korean Astronomical Society
• /
• v.28 no.1
• /
• pp.1-13
• /
• 1995

A list of radio sources in the field of Abell 2256 is presented at 1420 MHz. Also presented is the source count based on the list. This source count is taken with the sources above $7\sigma$ level at 1420 MHz. The overall characteristics of the count is consistent with that of a field where no galaxy cluster presents. The excess of radio sources due to the cluster is examined in the source count but it turned out to be unnoticiable as expected.

• Proceedings of the IEEK Conference
• /
• 2003.07b
• /
• pp.715-718
• /
• 2003

본 논문에서는 MOSFET source/drain 고체 확산 원으로써 도핑된 폴리 실리콘을 사용하였으며 확산 후 남은 폴리 실리콘은 elevated source/drain 역할을 하여 저항을 줄여 준다. 또한 제안 된 구조는 게이트 절연막 공정 이전에 확산 공정이 이루어 지기 때문에 후속 열처리에 취약한 고유전율 게이트 절연막 공정과 금속 게이트 공정에 적합한 공정으로 적합함을 보였다.

• Journal of Korea Technology Innovation Society
• /
• v.7 no.1
• /
• pp.1-20
• /
• 2004

In this paper, we try to explore the nature of open source software development process. The process involves peculiar characteristics which seem to defy the traditional economic reasoning for technology policy. Based upon the comparative case study of open source software development process with the two innovation processes adopted from literature on economic history, we argue that technology policy should strike the balance between provision of innovation incentives and voluntary disclosure of information.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• v.11B no.4
• /
• pp.164-168
• /
• 2001

In this paper voltage source FEA for hysteresis motor considering magnetic hysteresis characteristics is presented. The Preisach model is used as a hysteresis model. System matrix whose unknown variables are vector potentials and currents is formulated for voltage source. The stiffness matrix is maintained constant by using M-iteration method. Therefore the calculation time and efforts are reduced with Choleski direct method. Current waveform can be calculated for arbitrary voltage vaveform considering hysteresis effects.

• Journal of Soil and Groundwater Environment
• /
• v.16 no.6
• /
• pp.106-112
• /
• 2011

This study developed preliminary assessment methodology for priority listing of soil and groundwater contamination sources, considering source characteristics, local environments and risk receptors. Source characteristics were evaluated by scoring relative risk of contamination sources. Local environments were evaluated by scoring annual rainfall, hydraulic conductivity of aquifer, and annual groundwater use. Risk receptors were evaluated by scoring local population, direct distance to surface water, direct distance to drinking-water wells. Scores of each parameter were allocated by analysing distribution of parameter values obtained from government databases. Distributed scores of source characteristics local environments: risk receptors were 12 : 12 : 12. The preliminary assessment scored 0 to 36 for each soil and groundwater sources. Inventory of soil and groundwater sources consisted of 7 categories. This study applied the preliminary assessment methodology to Manan-Gu, Anyang City, Korea. The number of car repair and washing facility was the largest in the contamination source inventory. Petroleum storage facilities showed the highest assessment score. The preliminary assessment methodology also indicated that Anyang-Dong was the priority section among Anyang-Dong, Suksu-Dong, Bakdal-Dong. This study is the first trial for relative ranking soil and groundwater contamination sources by considering source and local characteristics. Therefore, further researches and revision of the preliminary assessment methodology need to be pursued for various applications.

• Fire Science and Engineering
• /
• v.33 no.1
• /
• pp.50-59
• /
• 2019

Experimental and numerical studies on the fire characteristics according to the distance between the fire source and sidewall under the over-ventilated fire conditions. A 1/3 reduced ISO 9705 room was constructed and spruce wood cribs were used as fuel. Fire Dynamics Simulator (FDS) was used for fire simulations to understand the phenomenon inside the compartment. As a result, the mass loss rate and heat release rate were increased due to the thermal feedback effect of the wall in the compartment fire compared to the open fire. As the distance between the fire source and sidewall was reduced, the major fire characteristics, such as maximum mass loss rate, heat release rate, fire growth rate, temperature, and heat flux, were increased despite the limitations of air entrainment into the flame. In particular, a significant change in these physical quantities was observed for the case of a fire source against the sidewall. In addition, the vertical distribution of temperature was changed considerably due to a change in the flow structure inside the compartment according to the distance between the fire source and sidewall.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.9 no.1
• /
• pp.23-28
• /
• 2008

Due to the modem MEMS technologies, the electron lenses that are used in the microcolumn can have much smaller optical aberrations compared with conventional electron lenses for the bulky electron columns. Since the electron lens system have great effect on the performance of the microcolumn, it is important to study the dependence of image quality on the configuration of the electronic imaging system, among which the source-lens part is most sensitive. In this work, we investigated the electron beam characteristics according to the shapes of extractor and limiting aperture that are elements of the source-lens part. By analyzing the data obtained, we proposed the optimum configuration of the electron lens system.

• Progress in Superconductivity and Cryogenics
• /
• v.6 no.2
• /
• pp.11-14
• /
• 2004

YBCO thin films have good characteristics for current limiting materials due to compact size and high current carrying capability. But the irregularities and the extreme thin thickness of YBCO films cause some difficulties in simultaneous quench and thermal shock protection. In order to solve these problems, vertical magnetic field generated from solenoid coil was applied to the YBCO element. And also to minimize the inductance caused by the serial connection of magnetic field source with superconducting elements, magnetic field source was separated from the power lines adapting protective current transformer. In this study, electric field-current (E-I) and quench characteristics of YBCO films were analyzed both by electrical measuring method and observations of bubble propagation. From the experiment results, it was revealed that the magnetic fields generated by surrounding coil could induce the uniform quench distribution for all stripes of current limiting units and finally simultaneous quenches were realized in all serial connection of YBCO elements. In addition, the separation of magnetic field source form electrical network could be good solution for simultaneous quench of YBCO films without any unnecessary effect caused by serial connection.

• Speech Sciences
• /
• v.10 no.3
• /
• pp.213-224
• /
• 2003

Spoken sound includes not only speaker's source but the characteristics of vocal tract and speech radiation. This paper is based on the theory of Park[1], who proposes the Phonation Type Index k; a variable that shows the characteristic of speaker's source excluding those of speaker's vocal tract and speech radiation. With Park's theory, we collect data by changing recording environments and expanding experimental data, and analyze the data collected to see whether or not the PTI k shows good discriminating power as a variable for speaker recognition. In the experiment, we repeatedly record 8 sentences ten times for each of 5 males in the environment of a recording room and an office, extract PTI k for each speaker, and measure the discriminating power for each speaker by using the value of PTI k. The result shows that PTI k has the excellent discriminating power of speakers. We also confirm that, even if the recording environment is changed, PTI k shows similar results.