• The Transactions of the Korea Information Processing Society
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• v.7 no.8
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• pp.2484-2496
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• 2000

High speed switches have been developing to interconnect a large number of nodes. It is important to analyze the switch performance under various conditions to satisfy the requirements. Queueing analysis, in general, has the intrinsic problem of large state space dimension and complex computation. In fact, The petri net is a graphical and mathematical model. It is suitable for various applications, in particular, manufacturing systems. It can deal with parallelism, concurrence, deadlock avoidance, and asynchronism. Currently it has been applied to the performance of computer networks and protocol verifications. This paper presents a framework for modeling and analyzing ATM switch using stochastic activity networks (SANs). In this paper, we provide the ATM switch model using SANs to extend easily and an approximate analysis method to apply A TM switch models, which significantly reduce the complexity of the model solution. Cell arrival process in output-buffered Queueing A TM switch with finite buffer is modeled as Markov Modulated Poisson Process (MMPP), which is able to accurately represent real traffic and capture the characteristics of bursty traffic. We analyze the performance of the switch in terms of cell-loss ratio (CLR), mean Queue length and mean delay time. We show that the SAN model is very useful in A TM switch model in that the gates have the capability of implementing of scheduling algorithm.

• Biomedical Science Letters
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• v.5 no.1
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• pp.75-84
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• 1999

In order to study the effects of $\alpha$-tocopherol acetate in glomerular injury, the minimal change nephrosis disease was induced by puromycin aminonucleoside (PAN) in spontaneously hypertensive rats, and we examined biochemical analysis in serum and morphological changes. The experimental animals were divided to control, PAN-treated (30 mg/kg, I.p.), vitamin E-treated (200 mg/kg, P.O.), and PAN+vitamin E-treated groups. After PAN injection, the rate of increase of body weight was lower than the other treatments. In addition, at 8 days after PAN injection, total protein content in serum was the lowest, whereas both blood urea nitrogen and serum creatinine contents were the highest in all experimental groups, which their changes of serum parameters were statistically significant. In morphological changes, the glomerular tissue at 8 days after PAN injection clearly showed obstruction of urinary space and proliferation of mesangial cells, and that loss and fusion of pedicles, vacuolization and edema of endothelial cells, and thickness of basal lamina were ultrastructurally showed in the glomerulus. Glomerular injury was significantly prevented by administration of vitamin E having an antioxidant effect. It suggested that the glomerular injury induced by PAN was accelerated by hypertension, and renal dysfunction might be induced by oxidative injury.

• Journal of the Korean Geophysical Society
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• v.7 no.3
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• pp.207-215
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• 2004

As the sea connecting with the East Sea, the Sea of Okhotsk is the most potential area of gas hydrates in the world. In other to examine geophysical structures of gas hydrate-bearing sediments in the Sea of Okhotsk, the CHAOS (hydro-Carbon Hydrate Accumulation in the Okhotsk) international research expedition was carried out in August 2003. In the expedition, high-resolution seismic and geochemical survey was also conducted. Sparker seismic profiles show only diffusive high-amplitude reflections without BSRs at BSR depth. It means that BSR appears to be completely different images on seismic profiles obtained using different frequencies. Many gas chimneys rise up from BSR depth to seafloor. The chimneys can be divided into two groups with different seismic characteristics; wipe-out (WO) and enhanced reflection (ER) chimneys. Different seismic responses in the chimneys would be caused by amount of gas and gas hydrates filling in the chimneys. In hydroacoustic data, a lot of gas flares rise up several hundreds meters from seafloor to the water column. All flares took placed at the depths within gas hydrate stability zone. It is interpreted that gas hydrate-bearing sediments with low porosity and permeability due to gas hydrate filling in the pore space make good pipe around gas chimneys in which gas is migrating up without loss of amount. Therefore, large-scale gas flare at the site on gas chimney releases into the water column.

• Korean Journal of Digital Imaging in Medicine
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• v.9 no.2
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• pp.39-43
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• 2007

In angiography, the global standard agreements of DICOM is lossless. But it brings on overload and takes too much store space in DICOM sever. Because of all those things we transmit images which is classified in subjective way. But this cause data loss and would be lead doctors to make wrong reading. As a result of that we try to transmit continued image (raw data) to reduce those mistakes. We got angiography images from the equipment(Allura FD20-Philips). And compressed it in two different methods(lossless & lossy fair). and then transmitted them to PACS system. We compared the quality of QC phantom images that are compressed by different compress method and compared spatial resolution of each images after CD copy. Then compared each Image's data volume(lossless & lossy fair). We measured spatial resolution of each image. All of them had indicated 401p/mm. We measured spatial resolution of each image after CD copy. We got also same conclusion (401p/mm). The volume of continued image (raw data) was 127.8MB(360.5 sheets on average) compressed in lossless and 29.5MB(360.5 sheets) compressed in lossy fair. In case of classified image, it was 47.35MB(133.7 sheets) in lossless and 4.5MB(133.7 sheets) in lossy fair. In case of angiography the diagnosis is based on continued image(raw data). But we transmit classified image. Because transmitting continued image causes some problems in PACS system especially transmission and store field. We transmit classified image compressed in lossless But it is subjective and would be different depend on radiologist. therefore it would make doctors do wrong reading when patients transfer another hospital. So we suggest that transmit continued image(raw data) compressed in lossy fair. It reduces about 60% of data volume compared with classified image. And the image quality is same after CD copy.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.7 no.1
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• pp.25-28
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• 2011

Autism is a developmental, neuropsychiatric disorder that begins in early childhood. A patient with autism seen in the dental office frequently may have many complications. Therefore, it may be needed to consider modified or alternative therapy for dental care of autistic patients. This is the case of a 16-year old boy who have autism. He came to the department of the pediatric dentistry, Yonsei University Dental Hospital, for evaluation and treatment of dentigerous cyst associated with impacted teeth(#33,34,35). Under daily hospitalization and general anesthesia, the cyst was enucleated with surgical extraction of #34 and autotransplantation of #33,35. And during the periodic dental followup, apexification of #33,35 was performed for periapical lesion and root maturity. At 2 year 6 months follow- up, now, bony healing was completed and there are some complications like external resorption of #33 and space loss of #34 area. Generally, the marsupialization has been widely recommended for treatment of dentigerous cyst. However, in this case, there is a little possibility of spontaneous eruption after marsupialization considering of patient's age, location and angulation of the impacted tooth, root maturity. And there is necessity to choose the treatment that has low recurrence risk and needs short-term follow-up for autism. Above all, poor oral hygiene and lack of cooperation for decompression treatment is a matter of primary consideration. Consequently, enucleation of the cyst was chosen for the final treatment plan in this case. It is important to consider the conditions that affect the eruption of a dentigerous cyst-associated tooth to predict the successful eruption and special health care needs of the patient when the treatment plan is settled.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.3
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• pp.421-429
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• 2001

Since Non-Extraction treatment in some orthodontic case shows unstable result and unfavorable profile, extraction is selected as inevitable treatment option for the harmonious profile, facial skeleton, and the stable dentition on both arches. For the achievement of proper goal, premolars, molars, sometimes incisors or canines are selected to be extracted. The first Premolar is usually extracted for relieving the crowded dentition with which the molar relations are class I to gain stable dentition and proper profile, but often results in the depression of profile or the loss of vortical dimension. On the contrary, the extracton of the second molar helps maintaining the fullness of profile and the vertical dimension, prevents additional space closural procedures which often make the procedures complicated, relieves both anterior and posterior crowding, and substitutes the extraction fossae for newly erupting 3rd molars. From the point of recurrence, the second molar extraction procedure, therefore, is more beneficial. This cases showed the good results of second molar extraction procedures in the patients with class I crowding.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.555-560
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• 2002

Replantation may be a treatment choice for a completely avulsed tooth caused by a traumatic injury. The outcome of replantation depends on the following factors ; minimal damage to pulp and periodontal membrane, the length of time the avulsed tooth was out of the mouth, how the tooth was stored, the level of root formation, etc. The time from the act of avulsion of the tooth to the actual replantation is especially important. Generally, when replanted within 30 minutes, more than 90% of the cases succeed, but when the time is between 30 to 90minutes, 43%, and greater than 90 minutes, 7%. This is a case of a replanted tooth with relatively good prognosis by ankylosis though there was a great time lapse since the tooth was avulsed. Though such treatment lead to loss of the tooth, in cases of children or adolescents, this treatment is meaningful, because it may earn time until any definitive therapy, functionally stimulate the alveolar bone to retain its height for a better prognosis for future treatment, and act as space maintainer.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.4
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• pp.613-618
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• 2009

Impacted molars are not usual with the prevalence rate of less than 1%, however problems such as infraocclusion, extrusion of the opposite tooth and lack of space are caused. If molars are impacted, radiographic check-up and observations are needed as they play an important role in skeletal development and mastication. Causes of impaction are underdevelopment of roots, supernumerary teeth, cysts, odontomas, ankylosis and etc. In our first case, we present impacted molar which was surgically exposed and orthodontically traded. As the developmental state of the root was less than half at first visit, we observed until the root was 2/3 in its length and traction was carried out. The second case is orthodontic traded molar with compleate enucleation of the existing cysts. When trading impacted molars, direct bonding of attachments to the tooth and light continuous forces are recommended so as to ankylosis, external absorption and periodontal attachment loss avoid. Fixed appliances tract the teeth on arch and obtain eruption spaces without patient's cooperation. We report surgically exposed and orthodontically traded molars which resulted in good occlusion and patients satisfaction.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.2
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• pp.174-183
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• 2001

During the rapid phase of gonadal development of the freshwater teleost, the catfish (Silurus asotus), the influence of hCG upon the inducement of final oocyte maturation and spawning was investigated electrophoretically and ultrastructurally. The electrophoretic patterns obtained were different in the presence and absence of some of the major or minor zones, because of the hormone level in catfish. The vitellogenin of hormone-treated fish was stained more intensively than that of sham-treated fish. These proteins showed some minor or main bands of egg extracts which migrated at positions corresponding to molecular weights of approximately 90,000. However, the thickness of electrophoretic band in molecular weight for hCG-treated fish was slightly lower than that for saline control. It seemed the plasma protein with molecular weight of approximately 45,000 in hCG-treated fish disappeared. In contrast to the control fish, the ovaries in the catfish treated with hCG shows a marked ultrastructural change under the electron microscope. No dilated profiles were seen in the granulosa cells of the mature oocyte before ovulation. After germinal vesicle breakdown (GVBD), the zona radiata interna (ZRI) becomes more compact, and there is a loss of all the processes from the pore canals. There is a wide space between the vitelline membrane and zona radiata. Also, during final maturation, the microvillar processes from the oocyte are seen no longer to penetrate deeply into the extracellular spaces of the overlying granulosa cells, and the reticulate patterns of the zona radiata interna becomes occluded, giving the zona radiata a more solid appearance. It has been possible to initiate 100% oocyte maturation in yolk granules and follicles in vivo by treatment with hCG and a high water temperature ($27^{\circ}C$). In hCG-treated fish, the percentages of successful artificial fertilization and hatching were maximal at 15 h after a single injection. It seems clear that a long acting preparation containing hCG can be successfully used in prespawning fish to advance the final events of gonadal maturation and initiate spawning. Further studies are necessary to evaluate the potential of hCG to either stimulate or inhibit the reproductive development of fish at other stages of the seasonal reproductive cycle.

• Journal of KIISE:Databases
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• v.35 no.6
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• pp.505-517
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• 2008

This paper proposes a rewriting algorithm of OWL-DL ontology query in SPARQL. Currently, to obtain inference results of given SPARQL queries, Web ontology repositories construct inference ontology models and match the SPARQL queries with the models. However, an inference model requires much larger space than its original base model, and reusability of the model is not available for other inferrable SPARQL queries. Therefore, the aforementioned approach is not suitable for large scale SPARQL query processing. To resolve tills issue, this paper proposes a novel SPARQL query rewriting algorithm that can obtain results by rewriting SPARQL queries and accomplishing query operations against the base ontology model. To achieve this goal, we first define OWL-DL inference rules and apply them on rewriting graph pattern in queries. The paper categorizes the inference rules and discusses on how these rules affect the query rewriting. To show the advantages of our proposal, a prototype system based on lena is implemented. For comparative evaluation, we conduct an experiment with a set of test queries and compare of our proposal with the previous approach. The evaluation result showed the proposed algorithm supports an improved performance in efficiency of the inferrable SPARQL query processing without loss of completeness and soundness.