• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.7
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• pp.1332-1339
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• 2001

SoC(System on Chip) technology is widely used in the field of embedded systems by providing high flexibility for a specific application domain. An important aspect of development any new embedded system is verification which usually requires lengthy software and hardware co-design. To reduce development cost of design effort, the instruction set of microprocessor must be suitable for a high level language compiler. And FPGA prototype system could be derived and tested for design verification. In this paper, we propose a 16 bit FPGA microprocessor, which is tentatively-named EISC16, based on an EISC(Extendable Instruction Set Computer) architecture for embedded applications. The proposed EISC16 has a 16 bit fixed length instruction set which has the short length offset and small immediate operand. A 16 bit offset and immediate operand could be extended using by an extension register and an extension flag. We developed a cross C/C++ compiler and development software of the EISC16 by porting GNU on an IBM-PC and SUN workstation and compared the object code size created after compiling a C/C. standard library, concluding that EISC16 exhibits a higher code density than existing 16 microprocessors. The proposed EISC16 requires approximately 6,000 gates when designed and synthesized with RTL level VHDL at Xilinix's Virtex XCV300 FPGA. And we design a test board which consists of EISC16 ROM, RAM, LED/LCD panel, periodic timer, input key pad and RS-232C controller. 11 works normally at 7MHz Clock.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.21 no.1
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• pp.7-13
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• 1991

An anatomic radiolucency called medial sigmoid depression can be observed on a number of panoramic and mandibular oblique lateral views in the ramus just below and anterior to the mandibular sigmoid notch. The radiolucency may be unilateral or bilateral. Seventy-eight mandibles of dry skulls were visually examined and radiographed by panoramic machine. The observable incidence, the location center, and the mean size of the medial sigmoid depression were studied. Additionally, the radiographic incidence of the depression was determined using 500 panoramic radiographs. Normal anatomic radiolucent areas in the jaws are encountered often in the radiographs taken for the usual dental practice purpose. Some of these radiolucencies can be misdiagnosed as pathologic entities. But in most cases, the size, location, and appearance of the radiolucent area, and the presence or absence of symptoms can lead one to the correct diagnosis before surgery is undertaken. And this can be secured if diagnosticians are aware of the common and varied appearances of the normal anatomic radiolucencies A depression in the ramus just below and slightly anterior to the most inferior aspect of mandibular sigmoid notch shows occasionally foramen-like or notch-like radiolucency on some panoramic and oblique lateral views. This radiolucency was named medial sigmoid depression by Langlais et a1. in 1983. Since there're no reports about this medial sigmoid depression after that, (The author retrieved the Mediline from 1983 to 1990: Cambridge scientific abstracts, (7200 Wisconsin Ave Bethesda MD 20814 U.S.A.) National Library of Medicine) the author studied the size and the location of the depression of the mandible specimens, and determined the relationship between the observable anatomic incidence and its reproducibility on the radiographs.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.1 s.119
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• pp.48-55
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• 2007

The aim of this article is to review the general property of the famous traditional Korean paper, "rice straw paper"(Bast-Fiber mixed with straw pulp), and to compare the paper qualities varying with the composition ratio of straw pulp, in order to revive the traditional paper in modem Korea. The experiment was carried out by making first the two different mixture papers, i. e., one is the paper of 50% bast fiber mixed with 50% straw pulp, and the other is the paper of 75% bast fiber with 25% oats straw pulp, and finally the 100% bast fiber paper was made for the purpose of comparison. The qualitative properties of these three kinds of paper with the different mixing ratio of the straw pulp were evaluated, and the findings of the experiment can be summarized as follow: 1. As to the quality aspects of the paper strength like tensile strength, breaking length, elongation, and tear strength, the test proved the 100% bast fiber paper as best, and the 50% mixed paper as the next good one. 2. In aspect of the printing adaptability such as density, opacity, brightness, whiteness, lab colors, air permeability, and roughness, the 50% mixed paper proved to be the best, due to the short cells in the straw pulp. 3. As to the air permeability, the larger ratio of straw pulp was found to be the lesser, and 75% bast fiber with 25% straw pulp mixture paper and the 100% bast fiber one were found 1/5 degree efficient. 4. In terms of the water absorption degree, 100% bast fiber paper was the fastest, but in case of mixture paper, 50% mixed one was a little faster up to the point of 1cm, while the two kinds of mixed ones appear to be almost similar to each other beyond the point. 5. The straw pulp mixed paper, especially the 50% mixed one was evaluated as the highest by the calligraphers who had experienced using the papers in terms of movement and feeling of the caligraphy and painting. In addition, although the 25% mixed paper is judged to be good for book printing because of the strength, the 50% mixed paper can be thought to be more desirable for painting and calligraphy. In conclusion, we will be able to make the quality paper with durability, by mixing the straw pulp with the bast fiber in proper ratio, following the tradition of Korean paper making.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.4
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• pp.347-353
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• 2010

Source terms of metal waste comprising a spent fuel assembly are relatively important when the spent fuel is pyroprocessed, because cesium, strontium, and transuranics are not a concern any more in the aspect of source term of permanent disposal. In this study, characteristics of radiation source terms for each structural component in spent fuel assembly was analyzed by using ORIGEN-S with a assumption that 10 metric tons of uranium is pyroprocessed. At first, mass and volume for each structural component of the fuel assembly were calculated in detail. Activation cross section library was generated by using KENO-VI/ORIGEN-S module for top-end piece and bottom-end piece, because those are located at outer core with different neutron spectrum compared to that of inner core. As a result, values of radioactivity, decay heat, and hazard index were reveled to be $1.40{\times}10^{15}$ Bequerels, 236 Watts, $4.34{\times}10^9m^3$-water, respectively, at 10 years after discharge. Those values correspond to 0.7 %, 1.1 %, 0.1 %, respectively, compared to that of spent fuel. Inconel 718 grid plate was shown to be the most important component in the all aspects of radioactivity, decay heat, and hazard index although the mass occupies only 1 % of the total. It was also shown that if the Inconel 718 grid plate is managed separately, the radioactivity and hazard index of metal waste could be decreased to 20~45 % and 30~45 %, respectively. As a whole, decay heat of metal waste was shown to be negligible in the aspect of disposal system design, while the radioactivity and hazard index are important.

• Proceedings of the Technology Innovation Conference
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• 1998.06a
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• pp.116-127
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• 1998

The Necessity of Cyber University. Within the rapidly changing environment of global economics, the environment of higher education in the universities, also, has been, encountering various changes. Popularization on higher education related to 1lifetime education system, putting emphasis on the productivity of education services and the acquisition of competitiveness through the market of open education, the breakdown of the ivory tower and the Multiversitization of universities, importance of obtaining information in the universities, and cooperation between domestic and oversea universities, industry and educational system must be acquired. Therefore, in order to adequately cope wi th these kinds of rapid changes in the education environment, operating Cyber University by utilizing various information technologies and its fixations such as Internet, E-mail, CD-ROMs, Interact ive Video Networks (Video Conferencing, Video on Demand), TV, Cable etc., which has no time or location limitation, is needed. Using informal ion and telecommunication technologies, especially the Internet is expected to Or ing about many changes in the social, economics and educational area. Among the many changes scholars have predicted, the development and fixations of Distant Learning or Cyber University was the most dominant factor. In the case of U. S. A., Cyber University has already been established and in under operation by the Federate Governments of 13 states. Any other universities (around 500 universities has been opened until1 now), with the help of the government and private citizens have been able to partly operate the Cyber University and is planning on enlarging step-by-step in the future. It could be seen not only as U. S. A. trying to elevate its higher education through their leading information technologies, but also could be seen as their objective in putting efforts on subordinating the culture of the education worldwide. UTRA University in U. S. A., for example, is already exporting its class lectures to China, and Indonesia regions. Influenced by the Cyber University current in the U.S., the Universities in Korea is willing .to arrange various forms of Cyber Universities. In line with this, at JUNAM National University, internet based Cyber University, which has set about its work on July of 1997, is in the state of operating about 100 Cyber Universities. Also, in the case of Hanam University, the Distant Learning classes are at its final stage of being established; this is a link in the rapid speed project of setting an example by the Korean Government. In addition, the department of education has selected 5 universities, including Seoul Cyber Design University for experimentation and is in the stage of strategic operation. Over 100 universities in Korea are speeding up its preparation for operating Cyber University. This form of Distant Learning goes beyond the walls of universities and is in the trend of being diffused in business areas or in various training programs of financial organizations and more. Here, in the hope that this material would some what be of help to other Universities which are preparing for Cyber University, I would 1ike to introduce some general concepts of the components forming Cyber University and Open Education System which has been established by JUNAM University. System of Cyber University could be seen as a general solution offered by tile computer technologies for the management on the students, Lectures On Demand, real hour based and satellite classes, media product ion lab for the production of the multimedia Contents, electronic library, the Groupware enabling exchange of information between students and professors. Arranging general concepts of components in the aspect of Cyber University and Open Education, it would be expressed in the form of the establishment of Cyber University and the service of Open Education as can be seen in the diagram below.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.3
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• pp.199-218
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• 2005

Purpose of Study: Peripheral nerve regeneration depends on neurotrophism of distal nerve stump, recovery potential of neuron, supporting cell like Schwann cell and neurotrophic factors such as BDNF. Peripheral nerve regeneration can be enhanced by the conduit which connects the both sides of transected nerve. The conduit maintains the effects of neurotrophism and BDNF produced by Schwann cells which can be made by gene therapy. In this study, we tried to enhance the peripheral nerve regeneration by using calcium phosphate coated porous conduit and BDNF-Adenovirus infected Schwann cells in sciatic nerve of rats. Materials and Methods: Microporous filter which permits the tissue fluid essential for nerve regeneration and does not permit infiltration of fibroblasts, was made into 2mm diameter and 17mm length conduit. Then it was coated with calcium phosphate to improve the Schwann cell adhesion and survival. The coated filter was evaluated by SEM examination and MTT assay. For effective allogenic Schwann cell culture, dorsal root ganglia of 1-day old rat were extracted and treated with enzyme and antimitotic Ara-C. Human BDNF cDNA was obtained from cDNA library and amplified using PCR. BDNF gene was inserted into adenovirus shuttle vector pAACCMVpARS in which E1 was deleted. We infected the BDNF-Ad into 293 human mammary kidney cell-line and obtained the virus plaque 2 days later. RT-PCR was performed to evaluate the secretion of BDNF in infected Schwann cells. To determine the most optimal m.o.i of BDNF-Ad, we infected the Schwann cells with LacZ adenovirus in 1, 20, 50, 75, 100, 250 m.o.i for 2 hours and stained with ${\beta}$-galactosidase. Rats(n=24) weighing around 300g were used. Total 14mm sciatic nerve defect was made and connected with calcium phosphate coated conduits. Schwann cells$(1{\times}10^6)$ or BDNF-Ad infected Schwann cells$(1{\times}10^6)$ were injected in conduit and only media(MEM) was injected in control group. Twelve weeks after surgery, degree of nerve regeneration was evaluated with gait analysis, electrophysiologic measurements and histomorphometric analysis. Results: 1. Microporous Millipore filter was effective conduit which permitted the adhesion of Schwann cells and inhibited the adhesion of fibroblast. We could enhance the Schwann cell adhesion and survival by coating Millipore filter with calcium phosphate. 2. Schwann cell culture technique using repeated treatment of Ara-C and GDNF was established. The mean number of Schwann cells obtained 1 and 2 weeks after the culture were $1.54{\pm}4.0{\times}10^6$ and $9.66{\pm}9.6{\times}10^6$. 3. The mRNA of BDNF in BDNF-Ad infected Schwann cells was detected using RT-PCR. In Schwann cell $0.69\;{\mu}g/{\mu}l$ of DNA was detected and in BDNF-Adenovirus transfected Schwann cell $0.795\;{\mu}g/{\mu}l$ of DNA was detected. The most effective infection concentration was determined by LacZ Adenovirus and 75 m.o.i was found the most optimal. Conclusion: BDNF-Ad transfected Schwann cells successfully regenerated the 14mm nerve gap which was connected with calcium phosphate coated Millipore filter. The BDNF-Ad group showed better results compared with Schwann cells only group and control group in aspect to sciatic function index, electrophysiologic measurements and histomorphometric analysis.