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Comparison of Plant Community Structures in Cut and Uncut Areas at Burned Area of Mt. Gumo-san (금오산(金烏山)의 산화지(山火地)에서 벌목지(伐木地)와 비벌목지(非伐木地)의 식물(植物) 군집구조(群集構造) 비교(比較))

  • Che, Sang-Hoon;Kim, Woen
    • Journal of Korean Society of Forest Science
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    • v.86 no.4
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    • pp.509-520
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    • 1997
  • This is a report on the early vegetation, plant community structure, and secondary succession of cut and uncut sites of burned areas in Mt. Gumo-sun. The forest fire occurred on April, 1994 and the pine forest and its floor vegetation were burned down. The investigation was carried out from April, 1995 to October, 1996. The results are summarized as follows : The floristic composition of cut and uncut sites of burned area and unburned area were composed of 32, 36, and 34 kinds of vascular plants respectively. The biological spectra showed the $H(G)-D_1-R_5-e$ type, $H(M)-D_1-R_5-e$ and $M(N)-D_1-R_5-e$ in cut, uncut, and unburned site respectively. The dominant species based on $SDR_3$ of the cut site were Miscanthus sinensis var. purpurascens(100.00). Caret humilis(52.27), Quercus serrata(51.19) and Lysimachia clethroides(39.40), however, in the uncut sites the dominant species were Quercus acutissima(56.91), Pinus densiflora(26.83) in the tree layer, Quercus serrata(50.43), Lindera glauca(40.51), Lespedeza bicolor(37.85) in the shrub layer, and Miscanthus sinensis var. purpurascens(72.27), Pteridium aquilium var. latiusculum(60.92), Carex humilis(63.63) in the herb layer. Pinus densiflora(99.88), Miscanthus sinensis var. purpurascens(82.74), Quercus serrata(77.47) and Carex humilis(74.02) were dominant in the unburned site. The species diversity(H) and evenness index(e) were 1.05, 0.70 and 1.32, 0.85 in the cut and uncut site, respectively and 0.22, 0.63 in the unburned site. Dominance index(C) was 0.15, 0.06 and 0.96 in the cut, uncut site and unburned site, respectively. Degree of succession(DS) was 345.19, 747.47 and 674.34 in cut, uncut and unburned site, respectively. The index of similarity(CCs) was 0.66 between cut and uncut sites, 0.50 between unburned and cut sites and 0.61 between unburned and uncut sites. The amount of exchangeable sodium, calcium, magnesium and soil pH were increased, but the amount of organic matter, available phosphous, total nitrogen, total carbon and exchangeable potassium were decreased in cut site after fire.

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Analysis on the Cooling Efficiency of High-Performance Multicore Processors according to Cooling Methods (기계식 쿨링 기법에 따른 고성능 멀티코어 프로세서의 냉각 효율성 분석)

  • Kang, Seung-Gu;Choi, Hong-Jun;Ahn, Jin-Woo;Park, Jae-Hyung;Kim, Jong-Myon;Kim, Cheol-Hong
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.7
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    • pp.1-11
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    • 2011
  • Many researchers have studied on the methods to improve the processor performance. However, high integrated semiconductor technology for improving the processor performance causes many problems such as battery life, high power density, hotspot, etc. Especially, as hotspot has critical impact on the reliability of chip, thermal problems should be considered together with performance and power consumption when designing high-performance processors. To alleviate the thermal problems of processors, there have been various researches. In the past, mechanical cooling methods have been used to control the temperature of processors. However, up-to-date microprocessors causes severe thermal problems, resulting in increased cooling cost. Therefore, recent studies have focused on architecture-level thermal-aware design techniques than mechanical cooling methods. Even though architecture-level thermal-aware design techniques are efficient for reducing the temperature of processors, they cause performance degradation inevitably. Therefore, if the mechanical cooling methods can manage the thermal problems of processors efficiently, the performance can be improved by reducing the performance degradation due to architecture-level thermal-aware design techniques such as dynamic thermal management. In this paper, we analyze the cooling efficiency of high-performance multicore processors according to mechanical cooling methods. According to our experiments using air cooler and liquid cooler, the liquid cooler consumes more power than the air cooler whereas it reduces the temperature more efficiently. Especially, the cost for reducing $1^{\circ}C$ is varied by the environments. Therefore, if the mechanical cooling methods can be used appropriately, the temperature of high-performance processors can be managed more efficiently.

STUDY ON THE NUISANCE IN THE ANIMAL FARM (축산공해(畜産公害)에 관(關)한 연구(硏究) -양돈업(養豚業)을 중심(中心)으로)

  • Jeon, C.G.;Kim, J.W.;Ra, G.Y.;Kim, K.J.
    • Korean Journal of Agricultural Science
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    • v.2 no.1
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    • pp.233-240
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    • 1975
  • This excrement was conducted to investigate the nuisance of swine excrement. And excrements were collected from 27 heads of swine Euseong swine breeding center and Hongdo-dong swine farm and amounts of faces and urine, nitrogen, phosphorus, and kalium contents and number of parasite were investigated, and for the purpose to clean of excrementing matter, ferment substance and moist soil added to swine excreting matter and floating matter. Heat decresement amount and biological oxygen demand were investigated. And the result obtained were as follows. 1) Average amount of daily excreting faces per swine was 500-2700g from Euseong swine breeding center and 450-2500g from Hongdo-dong swine farm and a mount of excreting urine was 450-4500g from both of farms. The rate of excrements between faeces and urine was 1:1 2) Nitrogen contents were 0.802 ppm in urine and 0.514 ppm in faces, phosphorus were 2.261 % in urine and 0.073% in faeces and kalium contents were 1.094% in and 6.0467% in faeces. 3) Strongyloides ransomi and intestinal modular worm eggs showed the highest of eggs number was the result of observation in parasites, and ascaris showed the next it, whip worm and lung worm showed the lowest. 4) The effect ferment substance additive, amount of dry matter, floating matter, heat decreasement amount and biological oxygen demand was decreased but not significant was appeared. And the effect of moist soil additive, it was more effective that fermented substance additive for the fermentation of swine excrement.

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The Effect of Ginseng Saponins on the Biosynthesis of Prostaglandins (인삼 Saponin이 Prostaglandin 대사에 미치는 영향)

  • Park C.W.;Lee S.H.
    • Proceedings of the Ginseng society Conference
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    • 1988.08a
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    • pp.77-80
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    • 1988
  • The effects of ginseng saponins and some phenolic acids on the in vitro biosynthesis of prostaglandins was examined in order to identify the role of some ginseng components on the regulaion of arachidonic acid metabolism. The productions of prostaglandin $E_2(PGE_2).$ prostaglandin $F_2{\alpha}(PGF_2{\alpha}).$ thromboxane $B_2(TxB_2)$ and 6-keto-prostaglandin $F_1{\alpha}(6-keto-PGF_1{\alpha})$ from $[^3H]-arachidonic$ acid were evaluated with rabbit kidney microsome. human platelet homogenate and bovine aortic microsome. The amounts of the total cyclooxy-genase products from arachidonic acid did't show significant changes in the presence of ginseng saponins. Panaxadiol. panaxatriol and all of the ginsenosides used in these experiments reduced the formation of $TxB_2.$ while increased the $6-keto-PGF_1{\alpha}$ production dose dependently. Ginseng saponins did't inhibit the ADP($10{\mu}M$) induced platelet aggregation. but sodium arachidonate (0.5 mM) induced platelet aggregation. but sodium arachidonate (0.5 mM) induced platelet aggregation was signiticantly inhibited. These findings suggest that ginseng saponins seem to playa role in the regulation of the arachidonate metabolism. probably by affecting the divergent biosynthetic pathway of prostaglandins from endoperoxide.

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Development of in-situ Sintered Ni-Al Alloy Anode for Molten Carbonate Fuel Cell (용융탄산염 연료전지용 in-situ 소결된 Ni-Al 합금 연료극 개발)

  • Chun, H.A.;Yoon, S.P.;Han, J.;Nam, S.W.;Lim, T.H.
    • Journal of the Korean Electrochemical Society
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    • v.9 no.3
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    • pp.124-131
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    • 2006
  • For commercialization of molten carbonate fuel cell (MCFC), it has some problems to be overcome such as decrease of porosity and thickness of the anode under the operating condition (at $650^{\circ}C$ and working pressure of more than 2 $kg_f/cm^2$). Recently, Ni-Al alloy anode has been proposed to replace the conventional Ni-Cr anode as an alternative material to resist a creep and inhibit the sintering. The objective of this research is to sinter the green sheet of Ni-Al alloy anode during single cell pre-treatment process, which has several advantages like cost down and simplification of manufacturing process. However, the Ni-Al alloy anode prepared with a conventional pre-treatment process showed the phase separation of Ni-Al alloy and formation of micropore(${\leqq}0.4{\mu}m$), resulting in low creep resistance and high electrolyte re-distribution. In order to prevent the Ni-Al alloy anode from phase-separating, nitrogen gas was used in the process of pre-treatment. Introducing the nitrogen, the phase separation from Ni-Al alloy into nickel and alumina was minimized and increased creep resistance. However, there was some micropore formation on the surface of Ni-Al alloy anode during the cell operation due to creation of lithium aluminate. Addition of more amount of electrolyte into a cell, especially at cathode, made the cell performance stable for 2,000 hrs. Consequently, it was possible to make the Ni-Al alloy anode with good creep resistance by the modified in-situ sintering technique.

Effect of Variety and Harvest Date on the Forage Production and Quality in Winter Rye (호밀의 품종 및 수확시기가 사초생산성 및 품질에 미치는 영향)

  • Lee, B.S.;Kim, J.D.;Kwon, C.H.;Chung, K.W.
    • Journal of Animal Science and Technology
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    • v.46 no.2
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    • pp.227-234
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    • 2004
  • This experiment was conducted at Cheonan Yonam Experimental Livestock Farm in 2001-2002 to detennine the effect of harvest date(20 April, 26 April and 4 May) on forage yield and quality of rye varieties of three different maturing groups(early maturing variety = ‘Koolgrazer’ midseason maturing variety = ‘Horni122’ and late maturing variety = ‘Danko’). The heading date of Kooigrazer, Hornil22 and Danko were 17, 22 and 29 April, respectively. Dry matter percentage increased from 15.6 to 21.6% as the harvest date was delayed from April 20 to May 4. Among the rye varieties tested, dry matter percentage of Koolgrazer, Hornil22 and Danko were 20.9, 18.8 and 16.3%, respectively. Dry matter yield increased from 1l.2 to 13.9 ton/ha as the harvest date was delayed, but no significant difference among rye varieties. As the harvest date was delayed, total digestible nutrients(TDN) yield also increased significantly from 7.4 to 8.4 ton/ha However no significant difference was found among rye varieties. Crude protein(CP) percentage decreased from 20.3 to 17.1% as the harvest date was delayed, and CP percentage of late maturing variety, Danko, was significantly higher than that of the other varieties. In content of fiber component(NDF, ADF, ADL, hemicellulose and cellulose) of rye, the late harvest date(4 May) showed the highest among harvest dates. From comparisoo within rye varieties tested, Kooigrazer, a early maturing variety had higher than a rnidseason and late maturing varieties, Hornill22 and Danko. The cellulase digestible of organic matter of dry matter(CDOMD) decreased as the harvest date was delayed. Among the rye varieties tested, the CDOMD of a early maturing variety, Koolgrazer was the lowest. Our study differences of winter rye in forage yield and quality resulting from variety maturity and harvest stage. A early maturing variety, Kooigrazer should be harvested between 24 and 28 April, Hamill 22(midseason maturing variety) harvested between 29 April and 3 May, Danko(late maturing variety) harvested between 4 and 8 May for maximum forage yield and optimum quality.

Effect of Silicate Mineral Filtered Water and Silicate Mineral Additive on Growth Performance and Pork Quality (규산염 광물질로 정수된 급이수 및 사료내 규산엽광물질 첨가제의 급여가 돼지의 성장능력 및 돈육의 품질에 미치는 영향)

  • Kong, C.S.;Ju, W.S.;Kil, D.Y.;Lim, J.S.;Yun, M.S.;Kim, Y.Y.
    • Journal of Animal Science and Technology
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    • v.46 no.5
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    • pp.743-752
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    • 2004
  • This experiment was conducted to investigate the effect of filtered water with silicate minerals on growth performance and pork quality. A total of 64 pigs were allotted at 37.95 kg body weight to 4 treatments in a randomized complete block(RCB) design. Each treatment had 4 replicates and treatments were I) Con(basaI diet). 2) Si-I(consumed silicate mineral filtered water and silicate mineral additive during 4 weeks before market weight), 3) Si-Il( consumed silicate mineral filtered water and silicate mineral additive during 8 weeks before market weight) and 4) Si-I1I(consumed silicate mineral filtered water and silicate mineral additive during 12 weeks before market weight). Silicate complex was added at 0.8% to basal diet. All pigs were allowed to feed and water ad libitum for 12 weeks. During last 4 weeks, average daily gain(ADG) in Si-Il and Si-III group was higher than that in Si-I group(P < 0.05). However overall experimental period, there were no significant differences in growth performance among all treatments. Acceptability of cooked pork at 7th day after slaughter in Si-lII group was higher than that in Con group(P < 0.05). The value of pH of fresh pork at 6 hours after slaughter was lower in Si-I1I group than that in Con group(P < 0.05). TBA values of fresh pork at 14th day after slaughter were lower in Si-II and Si-III groups than Con group(P < 0.05). These results demonstrated that pork quality could be improved when pigs consumed both silicate mineral and silicate mineral filtered water. However, growth performance was not improved by the consumption of silicate mineral filtered water and silicate mineral.

Determination of Energy Requirements for Maintenance in Hanwoo Steers (거세한우의 유지에너지 요구량 결정)

  • Kim, K.H.;Oh, Y.G.;Kim, W.;Lee, S.C.;Shin, K.J.;Jeon, B.T.
    • Journal of Animal Science and Technology
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    • v.46 no.2
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    • pp.193-200
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    • 2004
  • This experiment was carried out to determine energy requirements for maintenance of Hanwoo steers. Nine Hanwoo steers weighing 376.6$\pm$12.5kg were used in this experiment and fed rice straw(44%) and concentrate (56%) at three different energy levels; 0.8 times maintenance(0.8M), 1.2 times(1.2M) and 1.6 times(1.6M), respectively. Dry matter intake was 48.5, 65.9 and 86.5g/$BW^{0.75}$ for 0.8M, 1.2M and 1.6M, respectively. Increase in energy intake with the increased DM intake did not affect digestibilities of dry matter, organic matter, crude protein, crude fiber, crude fat and nitrogen-free extract. Gross energy intake averaged 190.8, 255.8 and 340.9kcal/BW0.75 for 0.8M, 1.2M and 1.6M, respectively. Energy loss was 41% feces and 0.6${\sim}$1.5% urine of gross energy intake. Further, energy loss from methane produced during rumen fermentation was 5${\sim}$9%, while body heat loss averaged 40${\sim}$60%. Intercept of the regression equation between ME intake and retained energy indicated that energy requirement for maintenance was 124.3kcal $ME/BW^{0.75}$.

Pharmacological Evaluation of the Mechanism of ${\alpha}-Adrenoceptor-Mediating$ Sleep in Chickens (${\alpha}$-아드레나린 수용체의 매개에 의한 병아리 수면에 대한 약리학적 고찰)

  • Jeong, S.H.;Sohn, U.D.;Song, C.S.;Hong, K.W.
    • The Korean Journal of Pharmacology
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    • v.20 no.2
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    • pp.15-21
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    • 1984
  • It was aimed to study the effects of ${\alpha}_2-adrenoceptor$ agonists on the sleeping time in $one{\sim}two-day-old$ chickens. Furthermore, it was also evaluated whether ${\alpha}_1-adrenoceptor$ agonist and antagonist might affect the sleeping in the chickens and discussed in relation with opiate receptor. 1) Guanabenz, clonidine, guanfacine and B-HT 933 decreased the latency of the loss of righting reflex in a dose-dependent manner, but B-HT 920 and oxymetazoline slightly prolonged it. 2) ${\alpha}_2-Adrenoceptor$ agonists produced dose·related increase in sleeping time. The potency was guanabenz>clonidine>oxymetazoline${\geq}$B-HT 933${\geq}$B-HT 920>guanfacine in this order. 3) ${\alpha}_2-Adrenoceptor$ antagonists decreased guanabenz-induced sleeping time in a dose ·dependent manner. The rank order of ${\alpha}_2-adrenoceptor$ antagonists was yohimbine>rauwolscine>piperoxan${\geq}$RX 781094. 4) Sleeping time caused by both ethanol and hexobarbital was not affected by yohimbine in chickens. 5) Methoxamine and phenylephrine showed little significant effect on the guanabenz-induced sleeping time. However, prazosin increased it. Paradoxically, corynanthine rather caused to decrease it. These results suggest that the stimulation of central ${\alpha}_2-adrenoceptor$ mediates sleeping, however it is remained uncertain in the role of central ${\alpha}_1-adrenoceptor$ in chickens. In addition, the one~two-day-old chickens may be considered as a useful, inexpensive and simple experimental model to evaluate the in vivo pharmacological action of the ${\alpha}_2-adrenoceptor$ agonist and antagonist related to sedation.

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Effect of Bulhwangeumjeonggi-san on Cytokine Levels of Mouse Th1/Th2 Cells and Anti-allergic Activity in Ovalbumin-sensitized Allergic Inflammation Model (불환금정기산(不換金正氣散)이 마우스 Th1/Th2 분화(分化) 및 알레르기 염증 반응 조절에 미치는 효과)

  • Lim, Kang-Min;Kang, Hee;Park, Sung-Min;Shim, Bum-Sang;Kim, Sung-Hoon;Choi, Seung-Hoon;Ahn, Kyoo-Seok
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.6
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    • pp.1467-1476
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    • 2006
  • This study was to evaluate the effect of Bulhwangeumjeonggi-san (BS) on mouse Th1 and Th2 cells' differentiation and ovalbumin (OVA)-induced allergic inflammation. The proliferation of mouse CD4 T cells and the secretion of Th1/Th2 cytokines under the influence of BS extract were measured as well as the amount ${\beta}$-hexosaminidase in RBL-wH3 cells and the levels of TNF-${\alpha}$ and IL-6 secretion in Raw264.7 cells. BALB/c mice were orally administered with BS extract and simultaneously inoculated with OVA to induce allergic reaction and measure the level of total lgE, OVA-specific lgE and the production of IFN- g, IL-4, IL-5 by the spleen cells. When mouse CD4- T cell were stimulated with anti-CD3 and anti-CD28 for 48 hours in various concentrations of BS extract, it increased proliferation of CD4 cells by 14% in 50 ${\mu}g/m{\ell}$ concentration but it showed an inhibition in higher concentrations. CD4 T cells under Th1/Th2 polarizing conditions for 3 days with BS resulted in mild decrease of IFN- g in Th1 cells and mild increase of IL-4 in Th2 cell at 50 ${\mu}g/m{\ell}$ but the level of IL-4 decreased by 18% at 100 ${\mu}g/m{\ell}$. BS extract had a dose-dependent inhibitory effect on antigen-induced release of ${\beta}$-hexosaminidase in RBL-2H3 cells. Treatment of BS extract on LPS stimulated Raw 264.7 cells showed dose-dependent decrease in TNF-${\alpha}$ production. Oral administration of BS extract on OVA-induced allergic mice showed an inhibitory effect on the levels of total serum lgE and OVA-specific lgE by 50% and 55%, respectively. Culture of spleen cells with OVA resulted in significant increase of IFN- g by 25% and significant decrease of IL-4 and IL-5 by 53%, and 38%, respectively. The results show that BS does not strongly induce mouse T cells to transform into Th1 or Th2 but it has an anti-allergic effect in vitro, and that it also corrects the unbalance between the reactions of Th cells in allergic diseases.