• Title/Summary/Keyword: z-buffer

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The Early Write Back Scheme For Write-Back Cache (라이트 백 캐쉬를 위한 빠른 라이트 백 기법)

  • Chung, Young-Jin;Lee, Kil-Whan;Lee, Yong-Surk
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.46 no.11
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    • pp.101-109
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    • 2009
  • Generally, depth cache and pixel cache of 3D graphics are designed by using write-back scheme for efficient use of memory bandwidth. Also, there are write after read operations of same address or only write operations are occurred frequently in 3D graphics cache. If a cache miss is detected, an access to the external memory for write back operation and another access to the memory for handling the cache miss are operated simultaneously. So on frequent cache miss situations, as the memory access bandwidth limited, the access time of the external memory will be increased due to memory bottleneck problem. As a result, the total performance of the processor or the IP will be decreased, also the problem will increase peak power consumption. So in this paper, we proposed a novel early write back cache architecture so as to solve the problems issued above. The proposed architecture controls the point when to access the external memory as to copy the valid data block. And this architecture can improve the cache performance with same hit ratio and same capacity cache. As a result, the proposed architecture can solve the memory bottleneck problem by preventing intensive memory accesses. We have evaluated the new proposed architecture on 3D graphics z cache and pixel cache on a SoC environment where ARM11, 3D graphic accelerator and various IPs are embedded. The simulation results indicated that there were maximum 75% of performance increase when using various simulation vectors.

Saccharomyces cerevisiae Live Cells Decreased In vitro Methane Production in Intestinal Content of Pigs

  • Gong, Y.L.;Liao, X.D.;Liang, J.B.;Jahromi, M.F.;Wang, H.;Cao, Z.;Wu, Y.B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.6
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    • pp.856-863
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    • 2013
  • An in vitro gas production technique was used in this study to elucidate the effect of two strains of active live yeast on methane ($CH_4$) production in the large intestinal content of pigs to provide an insight to whether active live yeast could suppress $CH_4$ production in the hindgut of pigs. Treatments used in this study include blank (no substrate and no live yeast cells), control (no live yeast cells) and yeast (YST) supplementation groups (supplemented with live yeast cells, YST1 or YST2). The yeast cultures contained $1.8{\times}10^{10}$ cells per g, which were added at the rates of 0.2 mg and 0.4 mg per ml of the fermented inoculum. Large intestinal contents were collected from 2 Duroc${\times}$Landrace${\times}$Yorkshire pigs, mixed with a phosphate buffer (1:2), and incubated anaerobically at $39^{\circ}C$ for 24 h using 500 mg substrate (dry matter (DM) basis). Total gas and $CH_4$ production decreased (p<0.05) with supplementation of yeast. The methane production reduction potential (MRP) was calculated by assuming net methane concentration for the control as 100%. The MRP of yeast 2 was more than 25%. Compared with the control group, in vitro DM digestibility (IVDMD) and total volatile fatty acids (VFA) concentration increased (p<0.05) in 0.4 mg/ml YST1 and 0.2 mg/ml YST2 supplementation groups. Proportion of propionate, butyrate and valerate increased (p<0.05), but that of acetate decreased (p<0.05), which led to a decreased (p<0.05) acetate: propionate (A: P) ratio in the both YST2 treatments and the 0.4 mg/ml YST 1 supplementation groups. Hydrogen recovery decreased (p<0.05) with yeast supplementation. Quantity of methanogenic archaea per milliliter of inoculum decreased (p<0.05) with yeast supplementation after 24 h of incubation. Our results suggest that live yeast cells suppressed in vitro $CH_4$ production when inoculated into the large intestinal contents of pigs and shifted the fermentation pattern to favor propionate production together with an increased population of acetogenic bacteria, both of which serve as a competitive pathway for the available H2 resulting in the reduction of methanogenic archaea.

Analysis of Methamphetamine and Amphetamine in Oral Fluid of Eleven Drug Abusers (마약남용자 11명의 타액 중 메스암페타민의 분석)

  • Kim, Eun-Mi;Lee, Ju-Seon;Choi, Hye-Young;Choi, Hwa-Kyung;Chung, Hee-Sun
    • YAKHAK HOEJI
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    • v.52 no.6
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    • pp.419-425
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    • 2008
  • A qualitative and quantitative analytical method was developed for detection of methamphetamine (MA) and its main metabolite amphetamine (AM) in oral fluid. Oral fluids of eleven drug abusers were provided by Police, specimens were collected by stimulation with a cotton swab treated with 20 mg of citric acid ($Salivette^{(R)}$; Sarstedt, USA). As the preliminary test, oral fluid samples were screened for amphetamines by Fluorescence Polarization Immunoassay (TDxFLx, Abbott Co.). Extraction for MA was performed using solid-phase extraction (SPE) by $RapidTrace^{TM}$ (Zymark, USA) with mixed mode cation exchange cartridge, CLEAN $SCREEN^{(R)}$ (130 mg/3 ml, UCT) after dilution with phosphate buffer. Samples were evaporated and derivatized by pentafluoropropionic acid anhydride (PFPA). Quantitation of MA and AM was performed by gas chromatography-mass spectrometry (GC-MS) using selective ion monitoring (SIM), the quantitation ions were m/z 204 (MA), 208 (MA-$D_5$), 190 (AM) and 194 (AM-$D_5$). The selectivity, linearity of calibration, limit of detection (LOD) and quantification (LOQ) within- and between day precision, accuracy and recoveries were examined as parts of the method validation. All oral fluid samples gave positive results to immunoassay for MA (cut-off level, 50 ng/ml as d-amphetamine). Concentrations of MA and AM by GC-MS in eleven samples were ranged 104.2${\sim}$4603.3 ng/ml and 32.4${\sim}$268.6 ng/ml, respectively. Extracted calibration curves of MA and AM were linear over the two concentration range of 1${\sim}$100 and 50${\sim}$1000 ng/ml with correlation coefficient of above 0.999. LOQ of MA and AM was 1 and 3 ng/ml, respectively. The intraand inter-day run precisions (CV) for MA and AM were less than 10%, and the accuracies (bias) for MA and AM were also less than 10% at the two different concentrations 5 and 100 ng/ml at low calibration range, 50 and 1000 ng/ml at high calibration range. The absolute recoveries of MA and AM at low and high calibration ranges were more than 82% and 75%, respectively. In this study the qualitative and quantitative analytical method of MA in oral fluid was established. Oral fluid testing may detect drug use in past hours because of its shorter detection window than urine, and be useful in post-accident situations. So oral fluids will be most useful for testing drug abuse in the driving under the influence of drug (DUID) as the alternative specimens of urine.

Studies on Thermophilic Flat-sour Bacteria in Soymilk: Isolation, Indentification and Determination of Heat Resistance (두유내의 고온성 Flat-sour 변질균의 분리.동정 및 열저항성에 관한 연구)

  • Chung, Je-Bong;Lee, Kyun-Hee;Sohn, Heon-Soo;Kim, Suk-Min
    • Korean Journal of Food Science and Technology
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    • v.20 no.2
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    • pp.218-224
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    • 1988
  • For the optimization of thermal processing conditions in soymilk process, 4 strains of thermoresistant flat-sour bacteria were isolated from soymilk. The isolates were aerobic spore-forming rods, and grew at $-65^{\circ}C$. Based on the morphological and physiological properties, all of the isolated strains were identified as Bacillus stearothermophilus. The heat resistance of spores of 3 isolates and Bacillus stearothermophillus ATCC 12980 as a reference was determined in soymilk(pH 7.0) and pH 7.0 buffer solution. For each of the spores studied, linear regression equations with standard error were presented for the thermal destruction at 110, 115, 121, and $125^{\circ}C$. It was not obvious that the components of soy milk increased the heat resistance of spores. Between the strains studied, variability was noted in the D values at the different temperature, and no one strain was consistently the most heat resistant at all the given temperatures. The average D value for the 4 strains was 77.27, 20.20, 2.76 and 1.39 min at 110, 115, 121 and $125^{\circ}C$, respectively, and the average z value was $8.36^{\circ}C$.

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DISTRIBUTION AND PHYSIOLOGICAL CHARACTERISTICS OF BACILLUS CEREUS IN RICE AND RICE PRODUCTS (미반류에 있어서 Bacillus cereus균의 분포와 생리적특성에 관한 연구)

  • LEE Myeong-Sook;CHANG Dong-Suck
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.13 no.4
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    • pp.163-171
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    • 1980
  • Recently, Bacillus has been identified as one of food poisoning bacteria especially in products of cereal foods in foreign countries. Therefore, the quantitative distribution of Bacillus cereus in market foods, its physiological characteristics, growth rate by temperature and heat resistance of its spore were examined. Thirty two samples of cooked rice, 20 samples of kimbab(cooked rice rolled with laver), 23 samples of rice cake, 13 samples of rice ana 13 samples of barley were collected from restaurents and food stores in Busan, Korea during the period from May to November in 1980. Forty samples of 101 samples submitted to the test appeared positive for Bacillus cereus showing abut $40\%$ in detection ratio. Detection ratio of Bacillus cereus was higher than $50\%$ in barley and rice, and about $30\%$ in rice products. Average Bacillus cereus content of in the samples was $2.6\times10^6/g$ in cooked rice, $2.3\times10^6/g$in kimbab, $4.9\times10^4/g$ in rice cake while that in rice and barley was about $10^3/g$. The result of biochemical tests of the bacterium was $100\%$ positive in catalase, egg yolk reaction, gelatin hydrolysis and glucose fermentation, $100\%$ negative in xylose, arabinose and mannitol oxidation, about $90\%$ positive in acetoin production, $80.0\%$ positive in nitrate reduction and citrate utilization and $55.0\%$ positive in starch hydrolysis test. Isolation ratio of Bacillus ceresus which showed haemolysis positive and starch hydrolysis negative results, was about $38\%$ in 40 strains examined. It is known that those strains has a close relation to food poisoning accident. Growth rate and generation time of Bacillus cereus isolated from the cooked rice were $0.34hr^{-1},\;2.02hr\;at\;20^{\circ}C,\;0.73hr^{-1},\;0.95hr\;at\;30^{\circ}C\;and\;0.49hr^{-1},\;1.44\;hr\;at\;40^{\circ}C$ respectively. Heat resistance value of Bacillus cereus spores suspended in phosphate buffer solution was $D_{90}=29.0min,\;D_{95}=8.7min,\;D_{98}=3.7\;min\;and\;D_{101}=2.3\;min(z=10.5)$.

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Bacterial Quality of Fish Meat Paste Products and Isolation of Thermoduric Bacteria (어육연제품의 세균학적 품질 및 내열성세균의 특성에 관한 연구)

  • 김동판;장동석;김성준
    • Microbiology and Biotechnology Letters
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    • v.13 no.4
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    • pp.409-415
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    • 1985
  • This study has been carried out in order to investigate the bacterial quality of fish meat paste products and the characteristics of isolated thermodurics from the products. Twenty samples of crab-flavored fish stick (Kematsal), 23 samples of plate fish meat paste (Panomuk, Kamaboko), 5 samples of fried fish meat paste (Tigimomuk), 2 samples of roasted fish meat paste (Puduromuk, Chikuwa), 20 samples of fish sausage were collected from processing plants and supermarkets in Pusan, Korea during the period from May to October in 1984. The results obtained are as follows. Amont the samples collected from supermarkets, roasted fish meat paste and fried fish meat paste marked hish counts in coliforms and fungi while very low in the samples of crab-flavored fish stick and plate fish meat paste. Salmonella was not detected in all the samples examined and Staphylococcus aureus was detected only in fried fish meat paste, Thermoduric bacteria were detected less than 10$^2$/g in the samples of crab-flavored fish stick and plate fish meat paste, which might come from subsidiary materials such as starch and seasonings. Among the isolated bacteria, distribution of the proteolytics were more than 87% and the lipolytics were less than 20%. Gram positive bacteria was more than 70% in crab-flavored fish stick and plate fish meat paste, 47.3% in fried fish meat paste. And rod in shape was almost more than 90% in all the samples. The most heat resistant bacterium isolated from the samples was identified as a Bacillus licheniformis(named B. licheniformis CR-11). The strain showed strong proteolytic activity and also grew well at above 2$0^{\circ}C$. The growth rate and generation time of CR-11 strain were 0.31 hr$^{-1}$ , 2.24 hr at 2$0^{\circ}C$, 0.64 hr$^{-1}$ , 1.09 hr at 3$0^{\circ}C$ and 0.78 hr$^{-1}$ , 0.89 hr at 35$^{\circ}C$. Heat resistance value of the spores of CR-11 strain suspended in phosphate buffer solution was D$_{85}$ $^{\circ}C$=41.9 min, D$_{90}$ $^{\circ}C$=27.9 min, D$_{95}$ $^{\circ}C$=10.2 min, D$_{100}$ $^{\circ}C$=4.3 min (Z=13.8$^{\circ}C$)

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REMINERALIZATION EFFECT OF INTERPROXIMAL CARIES ADJACENT TO GLASS IONOMER RESTORATIONS: IN VITRO STUDY USING QLF (QLF(Quantitative light-induced fluorescence)를 이용한 글라스 아이오노머 수복물의 인접면 우식 재광화 효과에 관한 연구)

  • Lee, Hyeok-Sang;Hyun, Hong-Keun;Jang, Ki-Taeg
    • Journal of the korean academy of Pediatric Dentistry
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    • v.38 no.3
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    • pp.244-249
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    • 2011
  • This in vitro study compared the remineralization of incipient interproximal caries in the presence of three glass ionomer cements(highly-filled glass ionomer cement, resin-modified glass ionomer cement, compomer) and a resin composite(control). Thirty-two extracted premolars were selected based upon the lack of any visible demineralization. The teeth were coated in a transparent acid resistant nail varnish leaving $3{\times}3$ mm square. The teeth were subjected to the demineralizing buffer for 3 days and quantitative light-induced fluorescence(QLF) images of the subjects were taken. Proximal restoration was simulated by placing tooth specimens and the various glass ionomer cements in closed containers with artificial saliva at $37^{\circ}C$ and pH 7.0 with constant circulation. Further QLF images were subsequently taken at 30, 60, and 90 days. The changes of mineral loss(${\Delta}Q$) were evaluated by QLF and the change of ${\Delta}Q$(${\Delta}{\Delta}Q$) were compared between groups in order to evaluate the effects of remineralization. All data were analyzed using ANOVA and the post-HOC Dunnett C multiple comparison test at p<0.05. While ${\Delta}Q$(changes of mineral loss) increased for all treatments, the increases for three glass ionomer groups were significantly higher than that for the resin group at first month period. As time went on, the amount of ${\Delta}{\Delta}Q$ decreased.

A Study on the Maintenance Plan of Trees in Gwanghalluwon Garden for Representing Traditional Space (전통공간 재현을 위한 광한루원의 수목정비방안 연구)

  • Lee, Won-Ho;Kim, Dong-Hyun;Kim, Jae-Ung;Ahn, Hye-In;Kim, Dae-Yeol;Cho, Un-Yeon
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.3
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    • pp.82-95
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    • 2014
  • This study aims to draw up measures to planting tree and maintain a landscape in traditional space. Preceding comprehensive theoretical consideration of selected species of trees and tree maintenance. And analysis of present condition of planting in cases of Gwanghalluwon Garden, then draw a maintenance plans of planting through species of trees and landscape of planting recorded in literature. The results were as follows. First, Analysis of selected species of trees and tree maintenance that traditional space. A dispute about the selection species of trees in traditional space has been continued until today. Because unconditional reject of foreign trees are limited. In this context, should be sublated that hasty blind faith of records and dichotomous preparation plans such as removal of foreign trees and implicitly planting of native plants. Secondly, Planted trees in Gwanghalluwon garden was investigated and found to the species of trees used in traditional space such as Pine(Pinus densiflora S. et Z.), Sawleaf Zelkova(Zelkova serrata), Ginkgo(Ginkgo biloba), Crape Myrtle(Lagerstroemia indica L.). But, present planting irrelevant to traditional space, except Gwanghallu pavilion area from the spatiality. Thirdly, A look at the records or literature that maintenance of planting through historical research are limited. Because literature was recorded Salix spp., Crape Myrtle, Bambusoideae(Pseudosasa japonica), lotus only among planted trees in Gwanghalluwon garden. Fourth, Gwanghallu zone have nature of history and sense of place. And It was going to restore the appearance on historical. Consequently maintenance plan of planting of Gwanghallu zone should be maintain the current state. Wanwol pavillion zone can be recognized as the original form because they look similar to the Gwangallu zone's buildings. Therefore, it is necessary to secure the sense of place different from Gwanghallu zone by buffer planting for composition of transition space. Wolmaejip zone and lawn zone was marketplace in outside of castle and large forest. Accordingly, this area should be symbolic restoration of the Yulrim(栗林) and representation of the marketplace in outside of castle through aggregation of facilities and administrative facilities in Gwanghalluwon garden. East lawn of the Wanwol pavilion zone is should be maintained the current state that opened place in terms of using thought linked with the Wanwol pavilion zone. Boundary zone of the Gwanghalluwon garden is difficult to associate in terms of historical research and authenticity. Therefore, application of cultural landscape that appeared in literature is be worth.