• Title/Summary/Keyword: Decrease rate

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Variation on Estimated Values of Radioactivity Concentration according to the Change of the Acquisition Time of SPECT/CT (SPECT/CT의 획득시간 증감에 따른 방사능농도 추정치의 변화)

  • Kim, Ji-Hyeon;Park, Hoon-Hee;Lee, Joo-Young
    • Journal of radiological science and technology
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    • v.44 no.6
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    • pp.645-653
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    • 2021
  • With the recent development of precision medicine(Theranostics), interest and utilization of the quantitative function of SPECT/CT are increasing. This study aims to investigate the effect on the radioactivity concentration estimate by the increase or decrease in the total time of SPECT/CT imaging conditions. A standard image was obtained by the conditions of a total acquisition time of 600 sec(10 sec/f × 120 frames) by diluting 99mTc 91.76 MBq in a cylindrical phantom filled with sterile water, and a comparative image was obtained by increasing the total acquisition time by -90%, -75%, -50%, -25%, +50%, +100%. The CNR, radioactive concentration estimate(cps/ml), and the variation rate(%) of the recovery coefficient(RC) were analyzed by measuring the overall coefficient of interest in each image. The results[CNR, Radiation Concentration, RC] by the change in the number of projections for each increase or decrease rate(-90%, -75%, -50%, -25%, +50%, +100%) of total acquisition time are as follows. [-89.5%, +3.90%, 1.04] at -90%, [-77.9%, +2.71%, 1.03] at -75%, [-55.6%, +1.85%, 1.02] at -50%, [-33.6%, +1.37%, 1.01] at -25%, [-33.7%, +0.71%, 1.01] at +50%, [+93.2%, +0.32%, 1.00] at +100%. and also The results[CNR, Radiation Concentration, RC] by the acquisition time change for each increase or decrease rate(-90%, -75%, -50%, -25%, +50%, +100%) of total acquisition time are as follows. [-89.3%, -3.55%, 0.96] at -90%, [-73.4%, -0.17%, 1.00] at -75%, [-49.6%, -0.34%, 1.00] at -50%, [-24.9%, 0.03%, 1.00] at -25%, [+49.3%, -0.04%, 1.00] at +50%, [+99.0%, +0.11%, 1.00] at +100%. Image quality(CNR) showed a pattern of change in proportion to the increase or decrease in the total acquisition time of SPECT/CT, but the result at quantitative evaluation showed a change of less than 5% in all experimental conditions, maintaining quantitative accuracy(RC less than 0.05) without much influence.

Assessment of Ruminal and Post Ruminal Amino Acid Digestibility of Chinese and Canadian Rapeseed (Canola) Meals

  • Chen, Xibin;Campbell, Lloyd D.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.7
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    • pp.979-982
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    • 2003
  • Two rapeseed meal samples (Sample A, hybrid 5900 and sample B, double low rapeseed No.4) obtained from China and one Canola meal sample obtained from a local crushing plant in Canada were used to investigate the amino acid degradability of rapeseed/Canola meal in rumen and amino acid digestibility of ruminal incubation residues by precision-fed rooster bioassay. Results show that in ruminal incubation the degradation rate of non amino acid nitrogen in crude protein is higher than that for amino acid nitrogen in crude protein, the results also suggest that the degradation rate of amino acid nitrogen in Chinese rapeseed meal sample B was lower than that for Canadian Canola, but that in Chinese rapeseed meal sample A is much close to that for Canadian canola meal. For all amino acids the digestibility of the bypass or residual protein as measured by the precision-fed rooster bioassay tended to be lower for Chinese rapeseed meal sample A than for sample B or Canadian canola meal which had similar digestibility values. However following a calculation of total amino acid availability, involving the digestibility of amino acids in the rumen and rooster bioassay the results are less contradictory. Results indicated that in traditional roasting-expelling process, heat treatment, especially dry heat treatmeat could decrease amino acids degradability in rumen of rapeseed/canola meal, but also may decrease total availability of amino acids of rapeseed/canola meal.

Effect of Chlorination for Bulking Control on the Organic Removal Activity of Activated Sludge Treating Dairy Wastewater (유가공 폐수의 활성슬러지 처리에서 벌킹 제어용 염소가 미생물의 유기물 분해 활성에 미치는 영향)

  • Nam Se-Yong;Choi Jin-Taek
    • Journal of Environmental Health Sciences
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    • v.32 no.1 s.88
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    • pp.96-101
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    • 2006
  • Chlorination inhibition on the organic removal activity of activated sludge microorganism was investigated in this study. It is well known that chlorination improves the settleability of filamentous bulking sludge through the selective impediment of filamentous microorganisms. However, it is based on the declination of effluent water quality after actual chlorination in dairy wastewater treatment plant. In case of the activated sludge which was exposed in the suggested concentration of chlorine $7.5\;mgCl_2/gVSS/day$ for the filamentous bulking control, decrease of organic uptake rate of $4.9\~24.0\%$, and dentrification rate of $24.8\~30.3\%$ ware shown in comparison to the control group which was not reacted with chlorine. As a result of comparing floc size of activated sludge microorganism, the average of floc diameter in the chlorine exposed group was $150\;{\mu}m$, which displays $25\%$ decrease compared with the control group.

Effect of Gamidojeok-san on Hypertension (가미도적산이 고혈압에 미치는 영향)

  • Sin Hwang Su;Oh Young Seon;Kim Yoon Sik;Seol In Chan
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.6
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    • pp.1710-1713
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    • 2004
  • This study was Investigated to prove the effect of Gamidojeok-san (Jiaweidaochi-san) on the hypertension. After administer Gamidojeok-san (Jiaweidaochi-san) extract to SHR(Spontaneous Hypertensive Rat) for 5 weeks, we examined changes of blood pressure, pulse rate, aldosterone and catecholamine in serum. Results : Following results were obtained; Gamidojeok-san(Jiaweidaochi-san) showed significant antihypertensive effect. Gamidojeok-san(Jiaweidaochi-san) decreased pulse rate but insignificant. Gamidojeok-san(Jiaweidaochi-san) showed a significant decrease in the aldosterone. Gamidojeok-san(Jiaweidaochi-san) was ineffective on the dopamine. Gamidojeok-san(Jiaweidaochi-san) decreased the norepinephrine but insignificant. Gamidojeok-san(Jiaweidaochi-san) showed a significant decrease in the epinephrine. These results indicate that Gamidojeok-san(Jiaweidaochi-san) can be used in hypertension. Further study will be needed about the functional mechanism and etc..

OH, PAHs and Soot Ditribution in a Laminar Diffusion Flame Under Oxidizer Deficient Ambience (산화제 결핍 분위기에서의 층류 확산화염내 OH, PAHs 및 그을음 분포)

  • Shim, Sung-Hoon;Shin, Hyun-Dong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.10
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    • pp.1348-1354
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    • 2002
  • We investigate the flame behavior and spatial distribution of OH, PAHs and soot in a confined buoyant diffusion flame with decrease of the coflowing air flow rate. Direct photographs and Schlieren images represent that flame is Ally occupied by blue flame and becomes unstable, which is partially detached to the fuel nozzle tip in a near extinction flame under extremely reduced oxidizer condition. Laser induced fluorescence profiles clearly shows that OH is still generated in near-extinction flame, although intensity becomes weak with decreasing air flow rate. But soot scattering image cannot be seen any more in an oxidizer deficient ambience and simultaneously the PAHs are widely distributed downstream. These results are due to that a decrease of oxygen concentration in the combustion chamber leads to a temperature drop of flame, as a consequence, to a delay in soot growth and to a expanding of the PAHs, as soot precursors.

Study of Effects of Harpagophyti Radix on Edema and Blood of Rats with Arthritis (관절염 백선의 부종과 혈액에 미치는 천수근의 효능연구)

  • Lee Joung Hun;Kim Youn-Sub
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.2
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    • pp.446-450
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    • 2004
  • Objectives: In order to study the effects of Harpagophyti Radix in rats with arthritis induced by Freund's complete adjuvant. Methods : In this study, rats with arthritis induced by Freund's complete adjuvant were divided into four groups; Normal, Control, Sample A(Harpagophyti Radix 6mg/200g) and Sample B(Harpagophyti Radix 12mg/200g). After 1 week, separated searches were made on the change of edema rate, the count of WBC, the quantity of total protein, total bilirubin, GOT and GPT in the serum. Results: In the right plantar edema, both of Sample groups showed a decrease in comparison with Control group. In the count of WBC, the quantity of serum total protein and SGOT, Sample B showed a decrease with statistical significance in comparison with Control group. In the quantity of serum total bilirubin and SGPT, both of Sample groups did not show any harmful change in in comparison with Control group. Conclusion : Reviewing these experimental results, it appeared that Harpagophyti Radix showed the therapeutic effect of anti-inflammatation on adjuvant arthritis.

The Influence of Freeze-Thaw Process on the Physical Properties of Weathered Granite Soils (2) (동결.융해반복작용이 화강암풍화토의 물리적성질에 미치는 영향(II))

  • 유능환;유연택
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.31 no.3
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    • pp.70-80
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    • 1989
  • In this research program special triaxial compression tests and dehydration-swelling tests under the condition of freeze-thaw process were conducted to show the effects of freezethaw process on the physical properties of weathered granite soil, and their results as follows; 1.Consolidation settlement of weathered granite soil mass was increased due to freeze-thaw process, and the initial tangent coefficient of dense state was higher than that of loose state. 2.Compression behaviour of soil was increased according to the decrease of freezing temperature, and when the freezing temperature was reached under - 10$^{\circ}$C, the compression rate was not influenced by change of freezing temperature. 3.The experiments showed that the void ratio and permeability of soil were converged into their values of shrinkage limit, and the permeability was higher due to the freeze-thaw process and as the lower the freezing temperature. 4.The decrease of liquid limit was indicated as the lower the freezing temperature, and as more the freeze4haw cycles, the moisture content was shown the lower side. 5.It was shown that the shrinkage was decreased by freeze-thaw process and not influenced by way of freezing temperature, but dehydration rate was higher.

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Computer Simulation of an Absorption Heat Pump for Recovering Low Grade Waste Heat (저온 폐열 회수를 위한 제1종 흡수식 열펌프의 컴퓨터 시뮬레이션)

  • Karng, S.W.;Kang, B.H.;Jeong, S.;Lee, C.S.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.8 no.2
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    • pp.187-197
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    • 1996
  • A computer program for thermal design analysis has been developed to predict the operating characteristics and performance of an absorption heat pump to recover $30{\sim}40^{\circ}C$ of waste hot water. The effects of heat transfer area of the system components, temperature and mass flow rate of heat transfer medium, and solution circulation rate on the system performance are investigated in detail. The results obtained indicate that the COP is increased with a decrease in the temperature of driving steam and with an increase in the temperature of waste hot water while the COP is little affected by the variation of a hot water temperature. It is also found that the heating output is increased with an increase in the temperature of waste hot water and driving steam as well as with a decrease in the temperature of hot water. The simulation results are also compared with the experimental results for a periodic operation of the system and obtained a satisfactory agreement.

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TCP-RLDM : Receiver-oriented Congestion Control by Differentiation for Congestion and Wireless Losses (TCP-RLDM: Congestion losses과 Wireless losses 구별을 통한 수신측 기반 혼잡제어 방안)

  • 노경택;이기영
    • Journal of the Korea Society of Computer and Information
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    • v.7 no.4
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    • pp.127-132
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    • 2002
  • This paper aims to adjust the window size according to the network condition that the sender determines by making the receiver participating in the congestion levels. TCP-RLDM has the measurement-based transmission strategy based on the data-receiving rate complementing TCP with the property of Additive Increase / Multiplicative Decrease. The protocol can make an performance improvement by responding differently according to the property of errors-whether congestion losses or transient transmission errors - to confront dynamically in heterogeneous environments with wired or wireless networks and delay-sensitive or -tolerant applications. By collecting data-receiving rate and the cause of errors from the receiver and by enabling sender to use the congestion avoidance strategy before occuring congestion possibly, the protocol works well at variable network environments.

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Degradation of Humic Acid in Ozone/GAC Process (오존/GAC 공정에서의 부식산 분해 특성)

  • Rhee, Dong Seok
    • Journal of Industrial Technology
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    • v.28 no.B
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    • pp.47-52
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    • 2008
  • In this study, GAC adsorption, ozonation and $O_3/GAC$ hybrid processes were investigated for treatment of humic acid. The degradation characteristics and efficiencies of humic acid in each process were evaluated through pH variation, $UV_{254}$ decrease, DOC removal, change of molecular size distribution and by-products formation. DOC removal rate in $O_3/GAC$ hybrid process (80%) was higher than arithmetic sum of ozonation (38%) and GAC adsorption process (19%) by synergism. $UV_{254}$ decrease rate of humic acid was also the highest than any other processes when treated in $O_3/GAC$ hybrid process. Molecular size distribution was not significantly changed in the GAC adsorption process. Main distribution of molecular size of humic acid was converted from 3 k~30 kDa into 0.5 k~3 kDa in ozonation. But the most of large molecular sizes of humic acid converted into small molecules(smaller than 0.5 kDa) in $O_3/GAC$ hybrid process. Quantities of formaldehyde and glyoxal formed in $O_3/GAC$ hybrid process were less than the ones in ozonation.

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