• Restorative Dentistry and Endodontics
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• v.13 no.1
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• pp.7-19
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• 1988

The object of this paper was to investigate the histopatological changes on dog's pulp under cavitation by irradiation of the $CO_2$ laser. The subjects were derived from four dogs, and irradiated 113.23 J/$mm^2$, 283.09 J/$mm^2$, 566.08 J/$mm^2$ in Group I, II, and III respectively. The dogs were sacrificed immediately, 24 hour, 72 hour and 1 week after $CO_2$ laser treatment. For light microscopic examination, routine H-E and PAS stains were employed. For electron microscopic observation, the teeth were fixed in 1% paraformaldehyde and 1% glutaraldehyde, decalcified teeth in 10% EDTA were stained by uranyl acetate and lead citrate. The observation was made with a Hitachi H-500 model electron microscope. The following results were obtained in this study: 1. At the early stage of the experimental sub-groups-immediately, 24 hour, 72 hour samples of Group I, II and III-coagulation necrosis and hyperemia were observed in odontoblastic and subodontoblastic pulpal layer. 2. At the 1 week sub-group of Group I, II, regenerative hyperplasia of the odontoblasts without coagulation necrosis were revealed, in addition to thickened predentin. On he other hand coagulation necrosis and atrophic change accompanying with hyperplasia were found at the 1 week sub-group of Group III. 3. Ultrastructurally, the odontoblasts appeared nuclear degeneration, vacuolar change of cytoplasmic organelles and rupture of plasma membrane at the early stage of the experimental period of all groups. 4. Under spectrohelioscopic examination, regenerative odontobalsts were seen at the 1 week specimens of Group I, II and III. 5. The pulpal response occured at 113-566 J/$mm^2$. The pathologic change of pulp tissue occured at the early experimental period but regeneration of odontoblasts could be seen after 1 week.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.4 no.1
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• pp.79-90
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• 1993

With immunohistochemical method, We have examined the distribution, the size, the number, and the morphology of somatostatin-immunoreactive neurons in the cerebral cortex of rats at the 1st. 2nd, 3rd, 4th postnatal week and the 2nd and 3rd months of age. The results are summarized as follows : 1) Strongly immunoreactive somatostatin neurons were found in the layer V and VI at the first postnatal week and then they were observed to be densely populated in the layer II and III from the 3rd postnatal week on as in the adult rat. 2) The size of the neuron was largest at the 2nd postnatal week while the number of the neurons was greatest in the 1st or 2nd postnatal week, depending on the different areas of the cortex. Overall the postnatal development of somatostatin neurons are well corresponds with the general principle of neuronal development of CNS.

• Physical Therapy Korea
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• v.3 no.3
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• pp.67-81
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• 1996

This study was performed to assess the efficacy of high voltage pulsed galvanic current for the healing of wounds in rabbits. Skin wounds were created laterally on the flank of 12 domestic rabbits($3{\times}3cm$). The wounds of each group were treated with an intensity of 170 V at a frequency of 70 pulses per second, which was applied for 30 minutes a day for 10 days. The experimental groups were randomly assigned to either EXP I (n=3), EXP II(n=3), EXP III(n=3) or control(n=3). Each group was stimulated under the following conditions : 1) EXP I (Negative polarity), 2) EXP II (Change in polarity, negative electrode stimulation during the first 3 days and then positive electrode stimulation from 4 to 10 days), 3) EXP III(Positive polarity), 4) control(No stimulation). An active electrode was placed over the wound and a dispersive electrode on the buttock. The rate of wound closure was compared with the original wound size, evaluated by a tracing film in each measurement period. Finally, on the wound in each group, skin tissue was excised for histological evaluation after treatment for 10 days. The results obtained are as follows : 1) It was found that the control group did not show a complete remodeling of epitherial layer and had a chronic inflammatory response. Judging from the irregularity of intercellular space and the loose alignment of connective tissue, these findings show that wound healing was delayed. 2) EXP I showed a significant bactericidal effect, but a moderate response of vasodilation. The rate of wound closure was slower when compared with EXP II, III. 3) EXP II showed a complete remodeling of epitherial layer and a positive repair of connective tissue. Its rate of wound closure was best when compared with the others. 4) EXP III had a slower rate of wound closure than EXP II, but judging from the greater proliferation of collagen fibers and the dense alignment of connective tissue, this positive electrode was very effective in the formation of neo - connective tissue.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.7
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• pp.525-530
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• 2004

A classifier was constructed by using a generalized regression neural network (GRU) and random generator (RG), which was applied to classify DNA sequences. Three data sets evaluated are eukaryotic and prokaryotic sequences (Data-I), eukaryotic sequences (Data-II), and prokaryotic sequences (Data-III). For each data set, the classifier performance was examined in terms of the total classification sensitivity (TCS), individual classification sensitivity (ICS), total prediction accuracy (TPA), and individual prediction accuracy (IPA). For a given spread, the RG played a role of generating a number of sets of spreads for gaussian functions in the pattern layer Compared to the GRNN, the RG-GRNN significantly improved the TCS by more than 50%, 60%, and 40% for Data-I, Data-II, and Data-III, respectively. The RG-GRNN also demonstrated improved TPA for all data types. In conclusion, the proposed RG-GRNN can effectively be used to classify a large, multivariable promoter sequences.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.6
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• pp.1068-1073
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• 1987

Traditional circuit partitioning algorithm using the cluster development method, which is suitable for such applications as single chip floor planning or multiple layer PCB system placement, where the clusters are formed so that inter-cluster nets are localized within the I/O connector pins, may not be appropriate for the functiona block placement in truly 3-D electronic modules. 3-D hybrid IC is one such example where the inter-layer routing as well as the intra-layer routing can be maximally incorporated to reduce the overall circuit size, cooling requirements and to improve the speed performance. In this paper, we propose a new algorithm called MBE(Minimum Box Embedding) for the layer assignment of each functional block in 3-D hybrid IC design. The sequence of MBE is as follows` i) force-directed relaxation in 3-D space, ii) exhaustive search for the optimal orientation of the slicing plane and iii) layer assignment. The algorithm is first explaines for a 2-D reduced problem, and then extended for 3-D applications. An example result for a circuit consisting of 80 blocks has been shown.

• Korean Journal of Environment and Ecology
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• v.25 no.2
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• pp.175-188
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• 2011

The purpose of this study was to investigate the vegetation structure of Daphniphyllum macropodum community in the Geumseon Valley area of Naejangsan National Park. To do so, thirty-seven plots($100m^2$) were set up and surveyed. The surveyed plots were divided into four groups according to the analysis of classification by TWINSPAN; (I)Carpinus laxiflora community (II)Carpinus laxiflora community (III)Deciduous Broad-leaved community and (IV)Zelkova serrata community. The results of vegetation structure analysis were; Daphniphyllum macropodum did not appeared in the canopy later but in understory and shrub layer. Even though Daphniphyllum macropodum will not be dominant species in the canopy later, but it was expected that Daphniphyllum macropodum will be major species in understory and shrub layer. The expected age of forest of the Geumseon Valley where Carpinus laxiflora and Zelkova serrata were dominant trees in canopy layer, was about 50 years old while that of Daphniphyllum macropodum in understory layer was 20 years old.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.153-154
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• 2002

Wear map of silver coatings on AISI 52100 has been constructed to delineate the wear transition behavior with the change in operating conditions in various environments. Three main regimes were clearly identified: (i) elastic/plastic deformation of silver coating without failure. (ii) mild wear regime after initial failure of silver coating and (iii) severe wear regime. In the mild wear regime, the contact surfaces were covered with transfer layers of agglomerated wear particles. The transfer layer acted as a protective layer and resulted in low friction even after the initial failure of the coated films, whose characteristics were strongly dependent on both the operating and environmental conditions. Also, the existence of the critical sliding speed, above which no transfer layer was able to form, was discussed in the work.

• The Journal of the Korean dental association
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• v.10 no.10
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• pp.654-658
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• 1972

The toplications of 50% nicotin paste in oral mucous membrane of male mice weigh-ingabout 30 gram, were executed for 10, 15 and 20 days. And the tissues were observed in HE and PAS stain. The findings observed are as follows; I. Hyperplastic changes were revealed in underlying connective tissue and spinous cell layer. There were moderate vasodilatations with out edema but PAS reactions were dictinctive. in 10th day of experiment. II. There was remarkable increment of mortality up to 40percent and weight loss, but microscopic findings were not significant differences on than 10th days, in 15th day of experiment. III. Cellular anisocytosis, hyperchromatism and degenerations were observed in spinous cell layer, and vascular engergement in connec tivetissues were observed. And the mortality was up to 70 percent in 20th day of experment.

• Restorative Dentistry and Endodontics
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• v.8 no.1
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• pp.61-68
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• 1982

This study was undertaken to compare the histopathological effects of the fractionated doses of 2,400, 4,800 and 7,200 rads of Cobalt-60 irradiation on the teeth of the sixty eight rats (Wester strain), weighing approximately 130gm. They were devided into four groups; no irradiation as a control (Group I) and others (Group II, III, and IV) which received different doses of radiation using 1.25 Mev RAC-120 Cobalt-60 Teletherapy Unit with exposure dose rate 69 rads/min, TSD 80cm. Experimental animals received 600 rads every three days until the total dosage of their groups were reached. Experimental animals were sacrified at the 1st day, 1st, 2nd, 3rd, 4th, 5th and 6th week irradiation. The following histopathologic findings were obtained: 1. The Group II, received 2,400 rads, showed no histopamologic changes essentially same as those of the control Group. 2. In the Groups III and IV, received 4,800 rads and 7,200 rads, disarray of the normal palasading arrangement of the odontoblastic cells, vacuolar degeneration in the odontoblastic layer, osteodentin and dentinal niches in the anterior teeth were observed. 3. There were no distinct changes in the posterior teeth in the Groups III and IV. 4. The ameloblast cells seemed to be less sensitive to radiation damage than the odontoblast cells.

• Korean Journal of Environment and Ecology
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• v.26 no.3
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• pp.426-436
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• 2012

This study was carried out to investigate actual vegetation, the structure of plant community, and ecological succession sere of coastal forest ecosystem in warm temperate climate zone, Taejongdae, Busan City, Korea to provide the basic data for planning of the forest management. As a result of analysis of actual vegetation, vegetation types divided into 35 types, and the area of survey site was $1,750,461m^2$. The ratio of vegetation type dominated by Pinus thunbergii was 80.7%, dominated by Quercus spp. was just 5.0%, and dominated by Carpinus tschonoskii was just 0.4%. Eighteen plots(size is $20m{\times}20m$) were set up and the results analyzed by DCA which is one of the ordination technique showed that the plant communities were divided into four groups which are community I(P. thunbergii community), community II(P. thunbergii-Quercus serrata community), community III(Q. serrata-P. thunbergii community), and community IV(Carpinus tschonoskii-P. thunbergii community). The age of community I was from 38 to 59 years old, that of community II was from 35 to 71 years old, that of community III was from 37 to 53 years old, that of community IV was from 50 to 72 years old, thus we supposed that the age of the study site is about from 38 to 72 years old. We supposed that the successional sere of the study site is in the early stage of ecological succession in the warm temperate climate zone. The dominant species will be changed from P. thunbergii to Q. serrata or Carpinus tschonoskii in the canopy layer, on the other hand, Eurya japonica will be dominant species in the understory layer, and E. japonica and Trachelospermum asiaticum var. intermediumwill be dominant species in the shrub layer for a while. According to the index of Shnnon's diversity(unit: $400m^2$), community I ranged from 0.8640 to 1.3986, community II was from 0.1731 to 1.1885, community III was from 0.8250 to 1.0042, and community IV was from 0.3436 to 0.6986.