• Journal of Sensor Science and Technology
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• v.10 no.2
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• pp.91-100
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• 2001

A $8{\times}8$ foveated (log-polar) retina chip for edge detection has been designed and fabricated using CMOS technology. Retina chip performs photo-input sensing, edge extraction and motion detection and we focused edge extraction. The pixel distribution follows the log-polar transform having more resolution in the center than in the periphery and can reduce image information selectively. This kind of structure has been already employed in simple image sensors for normal cameras, but never in edge detection retina chip. A scaling mechanism is needed due to the different pixel size from circumference to circumference. A mechanism for current scaling in this research is channel width scaling of MOS transistor. The designed chip has been fabricated using standard $1.5{\mu}m$ single-poly double-metal CMOS technology.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.6
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• pp.384-390
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• 2012

Purpose: The purpose of this study is to examine in vivo osteogenesis of cultured human periosteal-derived cells and polydioxanone/pluronic F127 scaffold. Methods: Two one-year-old miniature pigs were used in this study. $2{\times}10^6$ periosteal-derived cells in 1 mL medium were seeded by dropping the cell suspension into the polydioxanone/pluronic F127 scaffold. These cell-scaffold constructs were cultured in osteogenic Dulbecco's modified Eagle's medium for 7 days. Under general anesthesia with azaperone and tiletamine-zolazepam, the mandibular body and ramus of the pigs were exposed. Three bony defects were created. Polydioxanone/pluronic F127 scaffold with periosteal-derived cells and the scaffold only were implanted into each defect. Another defect was left empty. Twelve weeks after implantation, the animals were sacrificed. Results: New bone formation was clearly observed in the polydioxanone/pluronic F127 scaffold with periosteal-derived cells. Newly generated bone was also observed in the scaffold without periosteal-derived osteoblasts and empty defect, but was mostly limited to the periphery. Conclusion: These results suggest that cultured human periosteal-derived cells have good osteogenic capacity in a polydioxanone/pluronic F127 scaffold, which provides a proper environment for the osteoblastic differentiation of these cells.

• The Korean Journal of Malacology
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• v.23 no.2
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• pp.181-187
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• 2007

A scanning electron microscopic study on the glochidium and glochidial encystment of Anodonta arcaeformis on the host fish Carassius auratus was conducted. The shape of the glochidium was apparently subtriangular and its average size was $270\;{\mu}m\;\times\;260\;{\mu}m\;\times\;145\;{\mu}m$. The glochidial shell valves were of the same size, kept together by a ligament that is 50.4 ${\mu}m$ in length and 5.5 ${\mu}m$ in width. Each of the glochidial shell valve had a long hook studded with many spines on the superior face. A large area of at the apex of the valve surrounding the base of the hook was provided with numerous small spines which became progressively smaller toward the periphery of the area. The glochidial shell valve consisted of two layers. The mantle cells line the glochidial shell valves and some of hair cells were observed. A larval thread was 2.3 ${\mu}m$ in diameter. In the artificial infection of the glochidia to one of the natural hosts, Carassius auratus, it took about three to four hours to encyst the glochidia with epithelial cells of the fish fins. The encystment method was the cell migration from the neighboring epithelial cells.

• Journal of radiological science and technology
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• v.35 no.4
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• pp.321-326
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• 2012

Used as an ingredient in the hospital for orthopedic prosthetic stainless and titanium metal the same size as on the MRI diagnostic value of imaging were compared. Center of images, background high band portion of the video signal is converted into a weighted intensity values Normal images and compared. The area of normal slice and also the distortion of images and cross-sectional imaging of a range of quantitative and sagittal planes were compared. As a result, the periphery high band signal intensity values of Stainless video phantom 2, pig bone 1.8, Titanium imaging of phantom 1.7 has higher value than Normal video pig bone 1.3 times the signal strength rivers. MRI distortion of the shape and the distortions of the range, if the cross-sectional area compared to Normal Slice Stainless case of phantom 65.8 %, pig bone 61.5 %, Titanium distortion phantom 23.1 %, pig bone 38.5 % of the range of community found. In this experiment, as a result, MRI was found to be Titanium more diagnostic value than the specimen with respect to the signal intensity weighted value and low distortion range, Stainless.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.2
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• pp.262-269
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• 2002

The purpose of this study was to compare the effect of distance of light tip to resin surfaces and exposure time on the polymerization of surface and 2 mm subsurface of composite resins cured with two light sources; conventional halogen light (XL 3000, 3M, U.S.A.) and plasma arc light (Flipo, LOKKI, France) and compare the uniformity of polymerization from the center to the periphery of resin surfaces according to polymerization diameter cure with two light sources. From the experiment, the following results were obtained. 1. Difference of relative light intensity decrease in plasma arc light smaller than that of conventional halogen light(p<0.05). 2. In all groups, microhardness of top surfaces was decreased when distance of the light tip to resin surfaces is more than 2mm and increased according to increase of exposure time(p<0.05). 3. Difference of microhardness of the 2mm subsurface was rapidly decreased when distance of light tip to resin surfaces is more than 4mm(except, plasma arc light exposure time of 3 seconds). and the distance of light tip to resin surfaces and exposure time more affected 2mm subsurface rather than top surface(p<0.05). 4. Although exposure time was increased, difference of microhardness of the 2mm subsurface with the distance of light tip to resin surfaces was relatively high in groups between below 4mm and 6 mm(p<0.05). 5. Plasma arc light exposure time of 6 to 9 seconds produced microhardness values and microhardness change according to various distance similar to those produced with 40 to 80 second exposure to a conventional halogen light(p>0.05). 6. In all groups, microhardness was decreased gradually from the center to the periphery of resin surfaces(p<0.05).

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.2
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• pp.229-237
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• 2003

The purpose of this study was to compare the effect of exposure time on the polymerization of surface and 2 mm below the surface of light-cured restorative materials cured with three different light sources; conventional halogen light curing unit(XL 3000, 3M, U.S.A.), plasma arc light curing unit(Flipo, LOKKI, France) and light emitting diode(LED) light curing unit(Elipar Free light, 3M, U.S.A.) and compare the uniformity of polymerization from the center to the periphery of resin surfaces according to polymerization diameter cure with three different light sources. From the experiment, the following results were obtained. 1. In Z-100, Plasma arc light exposure time of 6 to 9 seconds and LED light exposure time of 40 to 60 seconds produced microhardness values similar to those produced with 40 second exposure to a conventional halogen light(p>0.05). 2. In Tetric Flow, Plasma arc light exposure time of 9 seconds and LED light exposure time of 40 to 60 seconds produced microhardness values similar to those produced with 40 second exposure to a conventional halogen light(p>0.05). 3. In Dyract AP, Plasma arc light exposure time of 6 to 9 seconds and LED light exposure time of 20 to 40 seconds produced microhardness values similar to those produced with 40second exposure to a conventional halogen light(p>0.05). 4. In Fuji II LC, Plasma arc light exposure time of 9 seconds and LED light exposure time of 20 to 60 seconds produced microhardness values similar to those produced with 40second exposure to a conventional halogen light(p>0.05). 5. Except Fuji II LC, microhardness was decreased from the center to the periphery in all light sources(p<0.05).

• Cross-Cultural Studies
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• v.25
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• pp.313-336
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• 2011

The objective of this thesis is to unfold Latin American trends overlapping with Korean contemporary novels as an interesting scene in the circle of Korea literature at the beginning of the 21st century. This study was conducted largely in two directions. One is examining how long novel A Guest of Seok-yeong HWANG, a representative realist writer in Korea, and another long novel One Hundred Years Motel (Baeknyeon Motel) of Cheol-woo IM, a writer who has expressed Korean shamanic flowering as his fictitious characteristic since the 1980s, meet and interact with the world of magic realism in long novel One Hundred Years of Solitude of G. G. Marquez born in Colombia, Latin America, and the other is discussing the fictional techniques of H. L. Borges overlapping with short stories in novel collections The Age of Twenty and Fictions of Midnight by, respectively, young writers Yeon-soo KIM and PARK Hyeong-seo who displayed a unique world of fictions in the 2000s. For these purposes, we developed the points of discussion from the viewpoint of 'the meeting of two essences' for Seok-yeong HWANG and Marquez, of 'the meeting of two 'hundred years'' for Cheol-woo IM and Marquez, of 'novel writing as the finding of the original' for Yeon-soo KIM and Borges, and of 'novel writing surrounding fictions' for Hyeong-seo PARK and Borges. Around 2000, the trend of Latin American novels emerged as a phenomenon in Korean novels. It was probably a natural consequence of contemporary writers' struggling with genres and post-genres, the overturn of the center and the periphery, and blurred boundaries. Seok-yeong HWANG, Cheol-woo IM, Yeon-soo KIM, and PARK Hyeong-seo borrowed the contents and techniques of Latin American novels, but further research is required on how continuously their works internalized the characteristic properties of Marquez-style, Borges-style or polyphonic Latin American novels and, by doing so, how much they expanded or determined their own line. This is why this study has been performed productively out of vital importance. In every age throughout history, there have been the phenomena of encountering and sympathizing, and overlapping and spreading with foreign novels. This study is meaningful in that it illuminated the aspects of Korean contemporary novels in the flow of world literature through tracing the origin and reality of the trend of Latin American novels emerging conspicuously through overlapping particularly with Korean novels published in the 2000s.

• Applied Microscopy
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• v.35 no.4
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• pp.91-97
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• 2005

The acinar cells and secretory granules of the parotid salivary gland were examined in the lesser white toothed shrew, Crocidura suaveolens and the big white-toothed shrew, C. lasiura. The parotid gland of both species were a serous gland having only one kind of serous acinar cells, and had conventional arrangement of acini and intercalated, granular and striated ducts. In case of C. suaveolens, serous acinar cells had well developed rER, prominent Golgi complex, several large mitochondria and abundant moderate dense secretory granules with various stages of the maturing or fusing process. Immature acinar secretory granules were only or mainly filled with fine strong dense specks and had an indistinct limiting membrane, and mature granules were filled with homogeneous pale large round center and had fine strong dense specks at the periphery of the homogeneous pale center and a distinct limiting membrane. In case of C. lasiula, serous acinar cells had well developed rER, prominent Golgi complex, several large mitochondria and abundant dense secretory granules with maturing or fusing process. Immature acinar secretory granules were only filled with pale rough specks and had an indistinct limiting membrane, and mature granules were only filled with rough dense specks and had a distinct limiting membrane. Eventually The acinar secretory granules of C. suaveolens were seen moderate at the light and ultrastuctural level, those of C. lasiura were strong dense at the light microscopic level and dense at the ultrastructural level.

• Cross-Cultural Studies
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• v.46
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• pp.411-434
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• 2017

With emphasis on various local cultures to confront the Western central culture, Ngugi wa Thiong'o proposes them 'to move horizontally' so as not to repeat the oppressive culture of the West. We need not only dialogues between dominant languages and peripheral languages, but also between marginal languages. With respect to this point, Ngugi thinks that translation itself could be very effective. Ngugi wants to stimulate writing and speaking in marginalized languages and promote translation as a means of making these languages visible. He regards translation as a conversational tool among languages and cultures in the multicultural global community. As is already well known, his determination to write his later works only in his native Gikuyu language has a great meaning in his anti-colonial as well as anti-neocolonial movement. Its proof is his recent effort to cooperate with Jalada Africa. Simon Gikandi criticized the English translation of Matigari as a denial of cultural hegemony of Gikuyu language and its subordination to the global cultural market. However, the concept of 'thick translation', helps us move from Gikandi's doubt of the 'epistemology of translation' to a meaningful strategy of postcolonial translation. Facing some of the scholars' doubts related to his over-stressing language problem, Ngugi points out that the world has managed to function well through translation: the possibility of translation between cultures and translation as a mediating tool for communication nationally as well as internationally. Based on this two-sided solution of translation, he believes that we can overcome the opposition between relativity and universality, center and periphery, and the dominant and the subordinate.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.3
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• pp.633-642
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• 2003

A pain is the symptom which defends against noxious stimulus about a human body, it is known that if the periphery of perceptive nerve were stimulated by a physical or chemical factors, the stimulation is induced by transmission to pain center in the cerebral cortex according to pain conduction tract. The treatment of pain is to decrease a stimulus that causes a pain or block off a nerve transmitting a stimulus or puts on a way to calm down pain center, but It is for adjustment of a pain to be the most representative in acupuncture among various ways to cure a pain in Oriental medicine. However, the analgesic effect of an individual response to acupuncture stimulation shows marked individual variations, so these days genetic a few approach is attempted. On this the author determined that the responding group was appointed those whose tail flick latency (TFL) responding time delayed the minimum of 30 % comparing with basal reaction time. For those whose TFL time had shorter than 30 % was grouped as a non-responding group. And then the hypothalamus of each group was dissected and RNA was further purified. After synthesizing cDNA using oligo dT primer, products were finally applied to the PCR. The results were as follows; The ratio of responding group to non-responding group was 6:4. Ach T (acetylcholinesterase T subunit), BF-I (Brain factor-I), DBH (Dopamine β-hydroxylase) and PNM (Phosphotidylethanolamine N-Methyltransferase) were revealed significantly in the responding group. Cathepsin B and Tau were revealed significantly in the non-responding group. The PCR results show that Ach T, BF-I, DBH and PNM are expressed abundantly in the responding group, where as cathepsin B and tau are abundant in the non-responding group. These results suggest that the analgesic effect on acupuncture stimulation is related to regulation of neurotransmitter as well as neurodegeration of cerebrum.