• Journal of the Korean Magnetics Society
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• v.3 no.2
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• pp.130-134
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• 1993

The magnetic properties of the amorphous $Fe_{73.5-X}Co_{X}Cu_{1}Nb_{3}Si_{13.5}B_{9}(x=2,\;4)$ alloys, fabricated by a single roll rapid quenching technique and annealed at $400~650^{\circ}C$, have been investigated. The optimum annealing temperature is $550^{\circ}C$ for the amorphous $Fe_{71.5}Co_{2}Cu_{1}Nb_{3}Si_{13.5}B_{9}$ alloy. The properties of the nanocrystalline $Fe_{71.5}Co_{2}Cu_{1}Nb_{3}Si_{13.5}B_{9}$ alloy show the relative permeability of $1.1{\times}10^{4}$ and the coercive force of 0.22 Oe at 1 kHz. When annealed at $600^{\circ}C$, the nanocrystalline $Fe_{69.5}Co_{4}Cu_{1}Nb_{3}Si_{13.5)B_{9}$ alloy shows the relative permeability of $1.0{\times}10^{4}$ and the coercive force of 0.19 Oe at 1 kHz. From the X-ray measurement, it is found that the remarkably improved soft magnetic properties are the effect of the formation of $\alpha$-Fe(Si) grain. By the results of FMR exper-imeIlt, the optimum annealing condition is just below temperature which the peak-to-peak line width of FMR spectrum increase rapidly.

• Applied Microscopy
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• v.33 no.2
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• pp.105-116
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• 2003

In Vitro fertilization of U. unicinctus eggs observed by immunofluorescence and electron microscopes revealed an overview of the meiotic pattern of the tide animals. The eggs have been fertilized early at germinal vesicle stage, followed by germinal vesicle break down (GVBD), but pre-mitotic aster like structure could not be resolved by the methods employed in this work. The meiotic features, such as rotation-shift movement of spindle fibers, behavior of spermatozoonmonaster in the egg cytoplasm and active spindle fiber of the 1st polar body, have been observed. The antitubulin-FITC fluorescence show the 2nd meiotic apparatus appeared firstly parallel to the tangential line of the oolemma, proceeding the meiosis, its bipolarity is rotated and shifted towards the oolemma. The polar bodysite of the oolemma was not amorphous, but active in a sense of anti-tubulin-FITC reactions during the extrusions of the polar bodies. The immunofluorescence reactions of the spermatozoon centriole appeared at a later stage of the 2nd meiosis. During the time periods, the fertilized spermatozoon resided in the egg cytoplasm. Activating the centrioles, spermatozoon approaches towards the chromosomal materials of the 2nd oocyte. This suggests that spermatozoon centrioles initiate and play a roll to fuse male and female pronuclei.

• Journal of Korean Society of Archives and Records Management
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• v.3 no.1
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• pp.1-21
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• 2003

In this paper the characteristics of the script centers golden and/or silver letter center in Koryo Dynasty and a set of seven rolls of the script written in silver letter on blue paper prayed by Yearn Seong-Ik were studied with focusing on the referred records and an epilog of the script. This script was discovered from Namgewon's stone stupa, when it was transported from original site of Daekam Dong, Kaiseong city to Kyungbok Palace in 1919. This script prayed by Yeom Seong-Ik which was written in silver paste on blue papers is a set of seven rolls, the size is 31.1 cm (length) ${\times}$ 27.2 cm (width). The cover painting and Beonsangwha(Buddha's preaching picture) were painted out and in the roll cover. This script was written with 14 letters on a line whose characteristic with the style of cover painting and Beonsangwha is similar to the golden and silver scripts prayed by kings of Koryo Dynasty. The person who prayed this script was a powerful vassal of the king Chungyeol period, Yeom Seong-Ik. According to Koryosa(Koryo History) and Koryosa jeolyo(summarized Koryo History), it is described that Yeom Seong-Ik offered his own house which was built by a group of strangers as a 'Writing Place for the complete collection of Buddhist Sutras and the place of the script of the complete collection of Buddhist Sutras. Therefore, it is possible to consider that this script a set of seven rolls of the script of Saddharma Pundarika-Sutra was written to pray for himself as well as his families' fortune at the place of golden script of the complete collection of Buddhist Sutras, and enshrined it in the Namgaewon stone stupa when the stupa was repaired in 9th year of king ChungYeol. Above all the most important point should be centered on that he offered his house as a writing place for golden script of the complete collection of Buddhist Sutras as recorded in Koryosa Jeolyo. The writing place for golden script of the complete collection of Buddhist Sutras should be emphasized on the meaning of its site. It is an important key point to clear that Kumjawon(Golden letter center) would be different from Kumjadejangso(the writing place of golden script for complete collection of Budihist Sutras) with Kumkyungsa(Goldm script place). As considereing the point that this script showed the characteristics of golden and/or silver scripts which prayed by king Chungyeol in Koryo Dynasty as they were, even though this script was manufactured by individual praying, this script follwed in the style of Kumjawon(golden letter center) and/or Unjawon(siIver letter center) as they were, because this script was written in the place of the golden script for the complete collection of Buddhist Sutras. In this paper all of the points described above with focusing on the referred records and an epilog of this script were collectively considered to make clear the characteristics of the script centers, golden and/or silver letter.

• Asia pacific journal of information systems
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• v.20 no.1
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• pp.127-140
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• 2010

The benefit that a consumer derives from the use of a good often depends on the number of other consumers purchasing the same goods or other compatible items. This property, which is known as network externality, is significant in many IT related industries. Over the past few decades, network externalities have been recognized in the context of physical networks such as the telephone and railroad industries. Today, as many products are provided as a form of system that consists of compatible components, the appreciation of network externality is becoming increasingly important. Network externalities have been extensively studied among economists who have been seeking to explain new phenomena resulting from rapid advancements in ICT (Information and Communication Technology). As a result of these efforts, a new body of theories for 'New Economy' has been proposed. The theoretical bottom-line argument of such theories is that technologies subject to network effects exhibit multiple equilibriums and will finally lock into a monopoly with one standard cornering the entire market. They emphasize that such "tippiness" is a typical characteristic in such networked markets, describing that multiple incompatible technologies rarely coexist and that the switch to a single, leading standard occurs suddenly. Moreover, it is argued that this standardization process is path dependent, and the ultimate outcome is unpredictable. With incomplete information about other actors' preferences, there can be excess inertia, as consumers only moderately favor the change, and hence are themselves insufficiently motivated to start the bandwagon rolling, but would get on it once it did start to roll. This startup problem can prevent the adoption of any standard at all, even if it is preferred by everyone. Conversely, excess momentum is another possible outcome, for example, if a sponsoring firm uses low prices during early periods of diffusion. The aim of this paper is to analyze the dynamics of the adoption process in markets exhibiting network effects by focusing on two factors; switching and agent heterogeneity. Switching is an important factor that should be considered in analyzing the adoption process. An agent's switching invokes switching by other adopters, which brings about a positive feedback process that can significantly complicate the adoption process. Agent heterogeneity also plays a important role in shaping the early development of the adoption process, which has a significant impact on the later development of the process. The effects of these two factors are analyzed by developing an agent-based simulation model. ABM is a computer-based simulation methodology that can offer many advantages over traditional analytical approaches. The model is designed such that agents have diverse preferences regarding technology and are allowed to switch their previous choice. The simulation results showed that the adoption processes in a market exhibiting networks effects are significantly affected by the distribution of agents and the occurrence of switching. In particular, it is found that both weak heterogeneity and strong network effects cause agents to start to switch early and this plays a role of expediting the emergence of 'lock-in.' When network effects are strong, agents are easily affected by changes in early market shares. This causes agents to switch earlier and in turn speeds up the market's tipping. The same effect is found in the case of highly homogeneous agents. When agents are highly homogeneous, the market starts to tip toward one technology rapidly, and its choice is not always consistent with the populations' initial inclination. Increased volatility and faster lock-in increase the possibility that the market will reach an unexpected outcome. The primary contribution of this study is the elucidation of the role of parameters characterizing the market in the development of the lock-in process, and identification of conditions where such unexpected outcomes happen.