• Title/Summary/Keyword: Shells

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Microtube Light-Emitting Diode Arrays with Metal Cores

  • Tchoe, Youngbin;Lee, Chul-Ho;Park, Junbeom;Baek, Hyeonjun;Chung, Kunook;Jo, Janghyun;Kim, Miyoung;Yi, Gyu-Chul
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.287.1-287.1
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    • 2016
  • Three-dimensional (3-D) semiconductor nanoarchitectures, including nano- and micro- rods, pyramids, and disks, are emerging as one of the most promising elements for future optoelectronic devices. Since these 3-D semiconductor nanoarchitectures have many interesting unconventional properties, including the use of large light-emitting surface area and semipolar/nonpolar nano- or micro-facets, numerous studies reported on novel device applications of these 3-D nanoarchitectures. In particular, 3-D nanoarchitecture devices can have noticeably different current spreading characteristics compared with conventional thin film devices, due to their elaborate 3-D geometry. Utilizing this feature in a highly controlled manner, color-tunable light-emitting diodes (LEDs) were demonstrated by controlling the spatial distribution of current density over the multifaceted GaN LEDs. Meanwhile, for the fabrication of high brightness, single color emitting LEDs or laser diodes, uniform and high density of electrical current must be injected into the entire active layers of the nanoarchitecture devices. Here, we report on a new device structure to inject uniform and high density of electrical current through the 3-D semiconductor nanoarchitecture LEDs using metal core inside microtube LEDs. In this work, we report the fabrications and characteristics of metal-cored coaxial $GaN/In_xGa_{1-x}N$ microtube LEDs. For the fabrication of metal-cored microtube LEDs, $GaN/In_xGa_{1-x}N/ZnO$ coaxial microtube LED arrays grown on an n-GaN/c-Al2O3 substrate were lifted-off from the substrate by wet chemical etching of sacrificial ZnO microtubes and $SiO_2$ layer. The chemically lifted-off layer of LEDs were then stamped upside down on another supporting substrates. Subsequently, Ti/Au and indium tin oxide were deposited on the inner shells of microtubes, forming n-type electrodes of the metal-cored LEDs. The device characteristics were investigated measuring electroluminescence and current-voltage characteristic curves and analyzed by computational modeling of current spreading characteristics.

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A Study on the application of checking the exuberance of yang (潛陽) to treat apoplexy (중풍(中風)의 치법(治法) 중 잠양법(潛陽法)에 대한 문헌고찰)

  • Min, Gun-Woo;Park, Jong-Hyuck;Jung, Ji-Cheon
    • The Journal of Dong Guk Oriental Medicine
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    • v.9
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    • pp.127-138
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    • 2000
  • The methods of checking the exuberance of yang (潛陽法) are a kind of medical treatments which cure various symtoms caused by hyperactivity of liver-yang, at the same time used for treating apoplexy. Thus, I investigated the application of checking the exuberance of yang to treat stroke. The conclusions are as follows. We can find application of checking the exuberance of yang to apoplexy on Synopsis of the Gold Chamber. After Ye Gui who persisted the theory of endogenous wind, many physicians applied the method of checking the exuberance of yang and this method has usually applied with nourishing yin. The methods of checking the exuberance of yang are concretely applied as follows. 1) a portion of apoplexy involving the channels and collaterals, which is caused by deficiency of yin and wind-fire pathogen. 2) excessive-syndrome of coma accompanied by heat syndrome. 3) epilepsy caused old apoplexy. The majority of shells for example abalone shell, hawksbill shell, oyster shell, tortoise-shell etc. are the most frequent use of herbal drug which check the exuberance of yang. The precriptions of checking the exuberance of yang are Ho-jam-hwan(虎潛丸), Ko-bon-dan(固本丹), Cheon-ma-gu-deung-eum(天麻鉤藤飮), Chin-gan-sik-pung-tang(鎭肝熄風湯) etc.

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Sr and Pb Isotopic Properties in Limnetic Gastropod (Semisulcospira libertina) Shell in the Jinan, Jeonbuk Area. (하천에 서식하는 민물고동(다슬기)의 Sr, Pb 동위원소 특성)

  • Jeon Seo-Ryeong;Chung Jae-il
    • Economic and Environmental Geology
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    • v.38 no.2 s.171
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    • pp.129-134
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    • 2005
  • The $^{87}Sr/^{86}Sr$ ratios between water and biogenic material are similar in marine and lacustrine environment. Pb isotope ratios we, however, reported not to have been corresponding between the biological tissues and ambient water in aquatic system, contrary to the Sr isotope ratios. In order to explore the potential application of two isotopes as environmental tracers, we report here the isotopic compositions of strontium and lead of gastropod shell in fresh water in Jinan area. The $^{87}Sr/^{86}Sr$ ratios of carbonate shells of gastropod living in fresh stream water, are similar as that of ambient water but are different by sites. The different $^{87}Sr/^{86}Sr$ ratios of stream water between the sites is likely caused by the difference of the isotopic composition of Sr derived form rocks in the basin. In contrast, there is a distinct difference of the lead isotopic values between the water and the gastropod shell, suggesting that shell-fish available lead in aquatic system is different from dissolved lead in water. It is assumed that the majority of Pb in stream water is derived from atmospheric Pb accumulated on soil materials over years rather than from rock.

A Investigation on the Soil-Peel Methods in Conservation Method of Historical Site (유구 보존방법론 중 토층전사에 관한 고찰)

  • Wi, Koang-Chul;Seo, Jeong-Ho
    • Journal of Conservation Science
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    • v.26 no.3
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    • pp.341-348
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    • 2010
  • After excavation work of relics, historical site which has historically meaningful, are preserved using the various methods. There are three method in the relocation methods that are original relocation method, the remaining structure-peel method, and soil peel method. The original relocation method is restored after relocating in historical site such as residential site, iron foundry site, kiln site, old mound. The remaining structure-peel method are restored only the feature of exposed remaining structure using polymeric resin, when it is difficult to relocate the entire remaining structure. And soil-peel method is exhibited after peeling in case when soil layers such as grave of old mound, foundation of building site, sedimentary deposit layer, shell heap, and etc. Soil-peel method becomes important historical data of changes according to environment at that time, that is, flooding by storm, traces of fire and living features of that time such as heaps of shells discarded after eating shellfish and living wastes. In particular, in case of soil layer for preparing foundation sites of building by compacting in turn soils with different components such as clay soil, rough sand soil and etc, it becomes important data which can judge foundation technology of that time. It can be said to be an important data preservation method for utilizing these historical data as historical data as well as for the purpose of education, exhibitions and public relations which can be shared not only by experts but also by general public. In this paper, we present the reliable definition of soil-peel method in various preservation methods and explain the using polymer in this method. So, we will come up with the accurate index about this method that is used the eminent analysis method for soil layer.

Utilization of Chitin Prepared from the Shellfish Crust 1. Functional Properties of Chitin, Chitosan, and Microcrystalline Chitin (갑각류부산물을 이용한 키틴의 제조 및 이용에 관한 연구 1. 키틴, 키토산 및 미세결정화 키틴의 기능특성)

  • AHN Chang-Bum;LEE Eung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.25 no.1
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    • pp.45-50
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    • 1992
  • To utilize shellfish by-products effectively, chitin, chitosan, and microcrystalline chitin were prepared from 6 kinds of crustacean shells(Antarctic krill, Euphausia superba; Red snow crab, Chinonecetes japonicus: Daelongsuyum shrimp, Solenocera prominentis: Lobster, Linuparus trigonus: Gasibal shrimp, Nephrops thomsoni: Blue crab, Portunus trituberculatus) and their functional properties were studied. Apparent volume(AV), settling volume(SV), water binding capacity(WBC), and fat binding capacity(FBC) of various chitins, chitosans, and microcrystalline chitins ranged from $3.1\pm0.1ml/g\;to\;27.0\pm0.2ml/g$ from $5.1\pm0.1ml/g\;to\;45.0\pm0.2ml/g,\;from\;318\pm40g/100g\;to\;2,382\pm12g/100g,\;and\;from\;235\pm20g/100g\;to\;2,169\pm20g/100g$, respectively, and the krill chitin and chitosan had the highest AV, SV, WBC, and FBC of them. Chitins and chitosans did not produce emulsion but microcrystalline chitins showed emulsifying properties. Emulsifying capacity and stability of various microcrystalline chitins ranged from $18.2\pm4.0\%\;to\;50.1\pm2.5\%\;and\;from\;15.2\pm3.5\%\;to\;31.1\pm1.0\%$, respectively. Dye binding capacity of microcrystalline chitins was higher than that of chitins or chitosans.

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A Study of Exploiting Raw Material of Seasoning by Using Fish and Shells -1. On Composition of Seasoning Material in Cooking By-product- (어패류를 이용한 조미료 소재 개발에 관한 연구 -1. 패류 자숙액즙의 성분조성-)

  • KIM Woo-Jun;BAE Tae-Jin;CHOI Jong-Duck;CHOI Ji-Hyun;AHN Myung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.27 no.3
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    • pp.259-264
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    • 1994
  • The possibility of shellfish utilization of juice as seasoning materials was examined through the analyzing proximate compositions and N-containing materials. The amounts of the sucking liquid wastes were estimated as 58,819 tons for oyster, 764 tons for pen-shell, 604 tons for cockle and 3,896 tons for blue-mussel from 1985 to 1990 in Korea. Water contents ranged from 95.2 to $97.4\%$ and crude protein level was $1.0{\sim}1.4\%$. Taurine was the most abundant nitrogenous compound($40{\sim}56\%$) in extracts, and glycine($10.4{\sim}36.1\%$), alanine($4.8{\sim}8.6\%$) and glutamic acid($3.1{\sim}5.3\%$) followed. More than $40\%$ of ADP and AMP as mucleotide were contained in all shellfish samples but pen-shell and cockle had $20\%$ of inosine, also. Glycinebetaine was present in corcentrations of 139.8mg/g in oyster and $45.5{\sim}61.9mg/100g$ in pen-shell, cockle and blue-mussel. Total creatinine and trimethylamine oxide levels were $30.4{\sim}59.1mg/100g$ and $0.82{\sim}47.2mg/100g$, respectively.

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Surgical Outcome of Cervical Arthroplasty Using $Bryan^{(R)}$

  • Kim, Hong-Ki;Kim, Myung-Hyun;Cho, Do-Sang;Kim, Sung-Hak
    • Journal of Korean Neurosurgical Society
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    • v.46 no.6
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    • pp.532-537
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    • 2009
  • Objective : Recently, motion preservation has come to the forefront of emerging technologies in spine surgery. This is the important background information of the emergence of cervical arthroplasty as an alternative to arthrodesis that offers the promise of restoring normal spinal movement and reduces a kinematic strain on adjacent segments. The study was designed to evaluate early surgical outcome and radiological effects of $Bryan^{(R)}$ cervical disc prosthesis. Methods : The authors retrospectively reviewed radiographic and clinical outcomes in 52 patients who received the $Bryan^{(R)}$ Cervical Disc prosthesis, for whom follow-up data were available. Static and dynamic radiographs were measured by computer to determine the angles formed by the endplates of the natural disc preoperatively, those formed by the shells of the implanted prosthesis, the angle of functional spine unit (FSU), and the C2-7 Cobb angle. The range of motion (ROM) was also determined radiographically, whereas clinical outcomes were assessed using Odom's criteria, visual analogue pain scale (VAS) and neck disability index (NDI). Results : A total of 71 $Bryan^{(R)}$ disc were placed in 52 patients. A single-level procedure was performed in 36 patients, a two-level procedure in 13 patients, and a three-level procedure in 3. Radiographic and clinical assessments were made preoperatively. Mean follow-up duration was 29.2 months, ranging from 6 to 36 months. All of the patients were satisfied with the surgical results by Odom's criteria, and showed significant improvement by VAS and NDI score (p < 0.05). The postoperative ROM of the implanted level was preserved without significant difference from preoperative ROM of the operated level (p < 0.05). 97% of patients with a preoperative lordotic sagittal orientation of the FSU were able to maintain lordosis. The overall sagittal alignment of the cervical spine was preserved in 88.5% of cases at the final follow up. Interestingly, preoperatively kyphotic FSU resulted in lordotic FSU in 70% of patients during the late follow up, and preoperatively kyphotic overall cervical alignment resulted in lordosis in 66.6% of the patients postoperatively. Conclusion : Arthroplasty using the $Bryan^{(R)}$ disc seemed to be safe and provided encouraging clinical and radiologic outcome in our study. Although the early results are promising, this is a relatively new approach, therefore long-term follow up studies are required to prove its efficacy and its ability to prevent adjacent segment disease.

Ecological Studies on the Sand Dollar, Astriclypeus manni (Verril 1867) - Feeding, Density and Locomotion (구멍연잎성게, Astriclypeus manni(VERRIL 1867)의 먹이섭취, 서식밀도 및 이동속도에 관하여)

  • 강도형;최광식
    • Korean Journal of Environmental Biology
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    • v.20 no.2
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    • pp.180-188
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    • 2002
  • Sand dollar, Astriclypeus manni (Echinodermata: Echinoidea) is widely distributed on subtidal sand flats all along the coast of Cheju Island. Limited information has been reported on their ecology despite their abundance. This study reports gut contents, density and locomotion of the sand dollars distributed on a subtidal sand flat on the north-east coast of Cheju Island. Microscopic examination of the gut contents indicated that A. manni feeds on inorganic and organic detritus as well as live organisms contained in the sediments. Inorganic particles included sand grains, sponge spicules and shells of benthic animals such as foraminifera, crustacean and molluscs. Mean diameter of sediment particles retained in the gut was $77.6\pm{22.2}\mu{m}$. Live organisms retained in the gut included foraminifera, harpacticoid copepods, nematodes, diatoms and unidentified egg. Spatial distribution pattern of the sand dollar was found to be random with a mean density of 0.4 individual $m^{-2}(\chi^2=85.16,\;p>0.05)$. Locomotion speed of the sand dollar measured in situ was 2.0 to 65.0 cm $hr^{-1}$. Locomotion speed and moving distance was somewhat higher in summer when food availability also higher.

Comparison and Analysis on Characteristics for recycling of Multifarious Food Waste (음식물쓰레기의 자원화를 위한 배출업종별 성상 및 특성의 비교분석)

  • Joo, Hung-Soo;Ryu, Jae-Young;Phae, Chae-Gun
    • Journal of the Korea Organic Resources Recycling Association
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    • v.9 no.4
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    • pp.117-124
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    • 2001
  • This study was executed for utilizing it as basic data in appropriate recycling way and design by examining and analyzing various characteristics of food waste which is being discharged from various restaurant and apartment house. In general, there were differences in restaurants classification and Japanese restaurant showed big differences as compared to other restaurants. Vegetable had the highest composition and its contents had big difference according to seasons. In alien substances, oyster shells were the highest and restaurants showed high rate of alien substances than apartments, therefore it was required to divide them in advance. Salinity was the highest in Japanese restaurants and most restaurants had rate of up to 1%, so it was not appropriate for recycling. However, it was considered that if there is cleaning operation in the whole process, there might not be a problem. Feed Ingredient had 28% of fiber, 25% of protein, and 11% of fats. We analyzed noxious germs and heavy metal too. However microorganisms of etiological cause were not detected and each harmful material showed less values of control concentration. In the result of analysis of each characteristic, it is required to consider collection rate from restaurants and apartments and seasonal cause into design regarding recycling. And apartments are compatible to compost than feed and food waste from Chinese, flour restaurant and collective feeding facilities are compatible for feed, as it is evaluated.

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Studios on the Pen Shell Culture Development (I) -Reproductive Ecology of Pen Shell in Yoja Bay- (키조개의 양식개발에 관한 연구(I) -여계만산 키조개의 번식생태-)

  • Yoo Sung Kyoo;Yoo Myong-Suk
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.17 no.6
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    • pp.529-535
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    • 1984
  • This study aims at obtaining the basic data for the development of pen shell culture at Yoja Bay, the southwest coast of Korea. The authors dealt with the annual gonadal changes of the pen shell, Atrina pectinata japonica, to find out the gametogenesis, reproductive cycle and spawning season, and to investigate the fluctuation in the larval occurence in Yoja Bay. From July 1983 to June 1984, an average of 20 individuals as specimens were monthly collected by commercial fishing dredge near Manwol island located at the mouth of Yoja Bay. The degree of gonadal development was determined by the histological observations as resting spent stage, early developmental stage, after developmental stage, early spawning stage, after spawning stage and degenerative stage. According to these degrees of gonadal development, annual reproductive cycle of the pen shell population was determined. From July to August, the gonads were changed through degenerative into resting stage and, in September and October, they became entirely empty gonads. From November they showed the first sign of gametogenesis developing very slowly. Nevertheless, the developing gametes did not increase in number probably owing to a phagocytic phenomenon by phagocytes which appeared in the gonad during this stage. Some individuals started spawning in April and in May majarity of individuals were in spawning stage. In June, majority of the individuals showed signs of degenerative stage. Therefore, the authors came to a conclusion that the pen shells in Yoja Bay spawn chiefly in May. And this is also supported by the result of the survey on the planktonic occurrences of the pen shell larvae. Namely, there were no larvae at all in April, only a few in May and many in June by vertical water sampling.

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