• Title/Summary/Keyword: Rings

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SOI CMOS Miniaturized Tunable Bandpass Filter with Two Transmission zeros for High Power Application (고 출력 응용을 위한 2개의 전송영점을 가지는 최소화된 SOI CMOS 가변 대역 통과 여파기)

  • Im, Dokyung;Im, Donggu
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.1
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    • pp.174-179
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    • 2013
  • This paper presents a capacitor loaded tunable bandpass chip filter using multiple split ring resonators (MSRRs) with two transmission zeros. To obtain high selectivity and minimize the chip size, asymmetric feed lines are adopted to make a pair of transmission zeros located on each side of passband. Compared with conventional filters using cross-coupling or source-load coupling techniques, the proposed filter uses only two resonators to achieve high selectivity through a pair of transmission zeros. In order to optimize selectivity and sensitivity (insertion loss) of the filter, the effect of the position of asymmetric feed line on transmission zeros and insertion loss is analyzed. The SOI-CMOS switched capacitor composed of metal-insulator-metal (MIM) capacitor and stacked-FETs is loaded at outer rings of MSRRs to tune passband frequency and handle high power signal up to +30 dBm. By turning on or off the gate of the transistors, the passband frequency can be shifted from 4GH to 5GHz. The proposed on-chip filter is implemented in 0.18-${\mu}m$ SOI CMOS technology that makes it possible to integrate high-Q passive devices and stacked-FETs. The designed filter shows miniaturized size of only $4mm{\times}2mm$ (i.e., $0.177{\lambda}g{\times}0.088{\lambda}g$), where ${\lambda}g$ denotes the guided wave length of the $50{\Omega}$ microstrip line at center frequency. The measured insertion loss (S21)is about 5.1dB and 6.9dB at 5.4GHz and 4.5GHz, respectively. The designed filter shows out-of-band rejection greater than 20dB at 500MHz offset from center frequency.

Physical and Chemical characteristics of Cokes Using Ash-Free Coal as binder (무회분 석탄(AFC)을 바인더로 이용한 코크스의 물리적 및 화학적 특성)

  • Kim, Gyeong Min;Kim, Jin Ho;Lisandy, Kevin Yohanes;Kim, Gyu Bo;Choi, Ho Kyung;Jeon, Chung Hwan
    • Korean Chemical Engineering Research
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    • v.55 no.3
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    • pp.395-400
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    • 2017
  • Coke strength was increased by adding ash-free coal (AFC) binder. In this study, the effect of the AFC binder on the physical and chemical properties of coke was experimentally investigated to understand the molecular mechanism for the improved coke strength. For reduced $CO_2$ emission in steelmaking industry, torrefied biomass fuel mixed with coal binder is also considered. The interface between the base coal and AFC was thus examined using Scanning Electron Microscope (SEM). The coke strength was commonly measured by performing the indirect tensile test and Nuclear Magnetic Resonance (NMR) spectroscopy in $^1H$ and $^{13}C$ modes. For comprehensive mechanism study of the enhanced coke strength thus obtained, ordinary coal for thermal power plant use was carbonized with AFC for subsequent SEM examination. The NMR spectroscopy results of coke samples positively revealed that the tensile strength was proportional to the average number of aromatic rings.

Growth of Ammodytes personatus in the South Sea, Korea (남해 신수도 연안에 분포하는 까나리(Ammodytes personatus)의 성장)

  • Kim, Yeong-Hye;Kang, Yong-Joo;Ryu, Dong-Ki
    • Korean Journal of Ichthyology
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    • v.12 no.3
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    • pp.166-172
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    • 2000
  • Growth of Ammodytes personatus was investigated based on the specimens collected in the costal waters of Shinsudo, Sacheon from March 20 to December 14, 1988. Age determination based on otolith. The rings in the otolith were used as the basis for age annulus. The time of ring formation was estimated to one time per year in May far 1st ring group and March for 2nd ring group. The spawning season peaked in December. It takes approximately 16 months for the first ring and 11 months for the second ring to form in the otolith. The opaque zone was formed and marked over summer at 1st ring group and spawning mark at 2nd ring group. The relationship between the total length(TL) and otolith radius(R), and body weight(BW) were represented respectively as follows: TL=29.17+182.9R, BW=$4.9{\times}10^{-8}TL^{3.9587}$. Von Bertalanffy growth model is $TL_t$ = 177.273 ($1_e^{-0.040(t+7.332)}$), Robertson growth model is $TL_t=\frac{150.275}{1+2.085e^{-0.099t}}$ and Gompertz growth model is $TL_t=157.551e^{-1.214exp(-0.069t)}$.

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A Study on the Anaerobic Treatment of the Phenol-bearing Wastewater with two Sludge Blanket-Packed Bed Reactors in Series (2단의 슬러지-고정상 반응기에서 페놀 함유 폐수의 혐시성 처리에 관한 연구)

  • 정종식;안재동;박동일;신승훈;장인용
    • Journal of Environmental Health Sciences
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    • v.21 no.4
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    • pp.1-9
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    • 1995
  • This study was carried to investigate the biodegradability of phenol in the wastewater with the two sludge blanket-packed bed reactor in series. Each reactor had a dimension of 0.09 m i.d. and 1.5 m height and consisted of two regions. The lower region was a sludge blanket of 0.5 m height and the upper region was a packed-bed of 1 m height. The packed bed region was charged with ceramic raschig rings of 10 mm i.d., 15 mm o.d. and 20 mm length. The reactors were operated at 35$\circ$C and the hydraulic retention time(HRT) was maintained 24 hours. The synthetic wastewater composed of glucose and phenol as major components was fed into the reactor in a continuous mode with incereasing phenol concentration. In addition, the nutrient trace metals($Na^+, Mg^{2+}, Ca^{2+}, PO_4^{3-}, NH_4^+, Co^{2+}, Fe^{2+}$ etc.) were added for growing anaerobes. The phenol concentration of the effluent, the overall gas production, the composition of product gas, the efficiency of COD reduction and the duration of acclimation period were measured to determine the performance of the anaerobic wastewater treatment system as the phenol concentration of the influent was increased from 600 to 2400 mg//l. Successfully stable biodegradation of phenol could be achieved with the anaerobic treatment system from 600 to 1, 800 mg/l of the influent phenol concentration. The upper level of influent phenol loading was high enough to meet most of the practical requirement. The duration of acclimation increased with the phenol loading. At steady state of the influent phenol concentration of 1800 mg/l, the treatment performance indicated the phenol reduction efficiency of 99%, the COD reduction efficiency of 99% and the gas production rate of 37 l/day. At the influent phenol concentration of 2400 mg/l, however, the operation of the treatment system was noted unstable. While the concentration of methane in biogas decreased with increasing the influent phenol loading, the carbon dioxide was increased. However, the concentration of hydrogen was varied negligibly. The concentration of methane was high enough to be used as a fuel. As a result, it is suggested that anaerobic phenol wastewater treament was economical in the sense of energy recovery and wastewater treatment.

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고대(古代) Egypt 복식(服飾)에 나타난 상징성(象徵性) - Tutankhamen 왕조(王朝)를 중심으로 -

  • Jeong, Heung-Suk
    • Journal of the Korean Society of Costume
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    • v.6
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    • pp.121-143
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    • 1982
  • Many studies have done on Egyptian Clothing because its unique characteristic culture. However, I was facinated by the exhibitions of Tutankhamen burial treasures which were shown in San Francisco and New York in 1978 and 1979. I found out myself that there are several interesting aspects of clothing to compare 18th dynasty king, Tutankhamun and other dynasties in Egyptian culture. Therefore, I tryed to analized the Egyptian clothing including accessaries with theigr symbols durin 18th dynasty King, Tutankhamun. The most of people were shocked and amazed when they toured the exhibition of Tutankhamun articles which were the most incredible burial treasures in existence today. The body of the King has been embalmed, bandaged and fitted in eight layers of coffins with pure gold mask to represent the god Osiris. Among eight layers of coffins, one is pure solid gold in mummiform, two of mummiforms are made of compact wood covered with sheets of gold and inlaid with multi-colored glass-paste and semi-precious stones. The Egyptian belived that the soul continued to exist throughout eternity if it had passed on examination of its deeds on earth at a "Last Judgement" presided over by Osiris. They also believed that the mummified body could exist in the tomb as a habitation that the soul could revisited. Thus a proper burial was vital for a full existence in the hereafter. They buried dead person in the sealed vault of the tomb with some of the possessions he had used during his life time, such as his furniture, clothing and jewels. In this studies, I've tried to research to various clothings, and accessories with their symbols used during 18th dynasty king, Tutankhamun. The studies are shown as: I) Clothings of Tutankhamun dynasity of Kalasiris, Sheath skirt. Gala skirt, Loin skirt, Hike and Dalmatic. The Dalmatic was first seen in this dynasty. Probably the Roman Christian borrowed the Dalmatica from Egyptian Dalmatic. No where has the same design at the period. II) Egyptian of 18th dynasty Tutankhamun wore big headdress, broad collar necklace passium, pendants, armlets, rings and earrings with very beautiful, exquisite handcraft. They seem the first people who wore earrings in Egyptian history. III) The symbols of decorated items vulture, lotus...Upper Egypt Uraeus, papyrus...Lower Egypt scaravaeus, Nile Riber...rebirth man(Ankh), +...eternal life solar disc, gold...sun ostrich-feather...nobleness God, Horus' eye...protection against enemy IV) Also Egyptian prefered the straight line and a right angle which were the basic principles of architectural arrangement.

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Metal Complexes of Ambidentate Ligand(Ⅳ). Nickel(Ⅱ) and Palladium(Ⅱ) Complexes of bis(isonitrosoacetylacetone)diimine Derivatives (Ambidentate 리간드의 금속착물 (제 4 보). Bis(isonitrosoacetylacetone)diimine 유도체를 리간드로 하는 니켈(Ⅱ) 및 팔라듐(Ⅱ) 착물)

  • Man-Ho Lee;Seon-Ho Lee
    • Journal of the Korean Chemical Society
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    • v.32 no.5
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    • pp.428-435
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    • 1988
  • Some nickel(Ⅱ) and palladium(Ⅱ) complexes of the ambidentate ligands derived from condensation of the isonitrosoacetylacetone and various diamines, $Ni(IAA)_2-en$, $Ni(IAA)_2-pn$, $Ni(IAA)_2-tn$, $Pd(IAA)_2-en$, PdCl(IAA)-pn, and $Pd(IAA)_2$-tn, where (IAA)$_2$-en, $(IAA)_2$-tn, and (IAA)-pn represent N,N'-enthylenbis(isonitrosoacetylacetone imine), N,N'-propylenebis(isonitrosoacetylacetone imine), N,N'-trimethylenebis(isonitrosoacetylacetone imine) and N-(2-aminopropyl)isonitrosoacetylacetone imine, respectively, have been prepared. The nickel(Ⅱ) and palladium(Ⅱ) complexes were characterized on the bases of the elemental analysis, IR, NMR, and electronic spectra. It is suggested that a isonitroso group of (IAA)$_2$-en or (IAA)$_2$-tn coordinates to the metal ion through the nitrogen atom to form five-membered ring, while the other isonitroso group of (IAA)$_2$-en or (IAA)$_2$-tn coordinates to the metal ion through the oxygen atom to form six membered ring in square-planar complexes of Ni(IAA)$_2$-tn and Pd(IAA)$_2$-en. And two isonitroso groups of (IAA)$_2$-en, (IAA)$_2$-pn, or (IAA)$_2$-tn coordinate to the metal ion through the nitrogen atom to form five-membered rings in square-planar complexes of Ni(IAA)$_2$-en, Ni(IAA)$_2$-pn, and Pd(IAA)$_2$-tn. On the other hand, square-planar PdCl(IAA)-pn is formed by the reaction of propylenediamine with a isonitrosoacetylacetone in the presence of palladium(Ⅱ)ion.

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First Report on Tomato bushy stunt virus Infecting Tomato in Korea

  • Kim, Mi-Kyeong;Kwak, Hae-Ryun;Jeong, Seon-Gi;Ko, Sug-Ju;Lee, Su-Heon;Park, Jin-Woo;Kim, Kook-Hyung;Choi, Hong-Soo;Cha, Byeong-Jin
    • The Plant Pathology Journal
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    • v.23 no.3
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    • pp.143-150
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    • 2007
  • A new virus-like disease of tomato showing chlorotic spots, malformation and necrosis on leaves, and chlorotic blotching, rings, and necrosis on fruits was observed around Sacheon, Gyeongsangnam-do, Korea in 2004. Host range analysis could not differentiate 4 field isolates collected from tomatoes showing different symptoms but identified them as Tomato bushy stunt virus (TBSV). TBSV-tsf2 isolate induced symptoms in indicator plants similar to those caused by the TBSV-C, -S and -Nf. As the isolate could not systemically infect Chenopodium quinoa, the isolate might belong to the previously described TBSV-S isolate. TBSV-tsf2 isolate caused similar cytological alterations that were similar to that generally caused by previously reported TBSV isolates. TBSV-tsf2 isolate, however, could be considered to belong to new strain of TBSV because masses of small electron-dense patches that were not observed from the previously described TBSV. The complete nucleotide sequences of the genomic RNA of 4739 nt excluding non-translated sequences at both termini have been determined and compared to sequences of other TBSV strains. The complete nucleotide sequence identity among TBSV isolates was 98.9% to 99.7%, and to the other tombusviruses ranged from 80.8% to 94.9%. Comparison of the amino acid sequences all five ORFs with those of other TBSV strains shows a similar genomic organization, and high percentage of amino acid sequence homology with TBSV-Nf than TBSV-S isolate. Since the TBSV symptoms were only observed in Sacheon fields where imported seeds from Japan were planted, the TBSV incidence probably caused by the planting contaminated tomato seeds and thus require more through quarantine procedure to prevent settlement of TBSV in Korea. Altogether, these results support that the Korean isolate of TBSV infecting tomato might be new strain.

Nitric Oxide/cGMP-Independent Vasorelaxation Enhanced by L-Arginine (L-Arginine의 산화질소생성과 무관한 혈관이완효과)

  • 문승호;이종은;유광재;오봉석;이동준
    • Journal of Chest Surgery
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    • v.31 no.2
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    • pp.102-107
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    • 1998
  • It has not been clear whether L-arginine plays solely a role contributing to vascular nitric oxide (NO) synthesis. To investigate the mechanisms by which L-arginine induces vasorelaxation, effects of L-arginine on the isometric tension, and tissue NOx and cyclic guanosine monophosphate(cGMP) contents were examined in the isolated rat thoracic aorta. L-Arginine induced a dose-dependent relaxation of aortic rings only with intact endothelium only. The vasorelaxation response to low concentrations of L-arginine was abolished by the pretreatment with NG-nitro-L-arginine methyl ester(L-NAME, 10-4 mol/L), whereas the relaxation caused by higher concentrations L-arginine(10-5-10-3 mol/L) was maintained and even more pronounced in the presence of L-NAME. L-Arginine did not affect the vascular tension precontracted with KCl. The vascular tissue contents of NOx/cGMP were not significantly affected by L-arginine, while they were decreased by L-NAME. L-Arginine could not completely recover the NOx/cGMP decreased by L-NAME. Methylene blue only partially antagonized the relaxation response to L-arginine. Indomethacin did not affect the L-arginine-induced vasorelaxation, whereas ouabain markedly attenuated the relaxation. It is suggested that L-arginine induces vasorelaxation not only through its contribution to NO synthesis, but also through enhancing another endothelium-dependent mechanism which is NO/cGMP-independent and cyclooxygenase- independent.

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The Protective Effects of Ascorbic Acid on the Vascular Motilities in Streptozotocin- induced Diabetic Rat (당뇨병 백서의 복부 대동맥 운동성에 대한 Vit C 의 보호효과)

  • 김영진;양기민;조대윤;손동섭;이무열
    • Journal of Chest Surgery
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    • v.34 no.7
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    • pp.515-523
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    • 2001
  • Background: More than 70% of morbidity and mortality of diabetes mellitus is due to macrovascular complications. These complications may be associated with defect of endothelium-dependent vascular relaxation. There have been suggestions that this defect might be due to direct toxicities of oxygen-free radical. So in this study ascorbic acid was used as a dietary supplement in streptozotocin induced diabetic rats to correct this defect. Material and Method: Sixty male Sprague-Dawley rats were used in this study. They were divided into control and experimental groups. Streptozotocin was injected to the 33 rats of experimental group and then divided into two the other receiving subgroups; one receiving ascorbic acid supplement(1 g/l in drinking water); and nosupplements. At 6, 9 and 12 weeks, abdominal aortic rings were obtained to make tissue preparations for evaluation of vascular smooth muscle contractility. Result: While control group showed good response to acetylcholine induced relaxation, diabetic group showed decreased relaxation regardless of ascorbic acid supplement at the experiments 6 weeks after streptozotocin treatment. This abnormal endothelium-dependent vascular relaxation was markedly reversed at 9 and 12 weeks into the diabetic group with ascorbic acid supplement. There were no differences in sodium nitroprusside induced relaxation responses between control and experimental groups; also, norepinephrine induced contractile responses did not show any remarkable effects. Conclusion: These results strongly suggest that the endothelial cells have defects in diabetic rats. Dietary supplement of ascorbic acid can reverse the defects of diabetic endothelial cells through its antioxidant effects and it may further protect against vascular disease in diabetic patients.

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Age and life history of an old black pine (Pinus thunbergii Parl.) tree at Cave Temple on Mt. Sanbangsan, Jeju Island, Korea, died due to pine wilt disease in 2013

  • Kim, Eun-Shik;Lee, So-Hee;Kim, Joon-Bum;Kim, Chan-Soo;Yoon, Bong-Taek;Lee, Sung-Hoon;Lim, Wontaek;Kim, Hyojung;Choi, Junghwan;Han, Hyerim
    • Journal of Ecology and Environment
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    • v.38 no.1
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    • pp.85-93
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    • 2015
  • In 2013, the epidemics of pine wilt disease caused by the pine wood nematodes (Bursaphelenchus xylophilus) resulted in damages to the forests of black pine (Pinus thunbergii Parl.) trees in Jeju Island, Korea. Among the affected trees, an old black pine tree at Cave Temple on Mt. Sanbangsan was included and died due to the prevalence of pine wilt disease. The tree was on Mt. Sanbangsan, which was designated as a National Scenic Place with the Number 77 and was believed to be more than 400 years old in age. By examining the disc of the tree stem obtained from the height of 2 m, we counted the tree rings from 4 different directions and cross-dated the readings by comparing the records of drought simulated from the BROOK Model. Our analysis indicates that the tree seems to have grown since late 1860s. Contrary to the belief of the general public, we can conclude that the age of the tree was estimated to be at maximum 150 years, which means that it was not the same old tree as was shown in the painting of the Tam-Ra-Sun-Ryeok-Do (an old painting book for the Inspection Tour of Jeju Island) published in 1702. Discussion was extended to the life history of the tree in growth and leaning and the measures to protect the tree species from the damages of the pine wilt disease caused by pine wood nematodes.