• Title/Summary/Keyword: Dead Times in Series

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COUNTING STATISTICS MODIFIED BY TWO DEAD TIMES IN SERIES

  • Choi, H.D.
    • Nuclear Engineering and Technology
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    • v.43 no.3
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    • pp.287-300
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    • 2011
  • Counting statistics modified by introducing two dead times in series under a Poisson input distribution are discussed. A previous study examined the two cases of series combinations of nonextended-extended (NE-E) and extended-extended (EE) dead times. The present study investigated the remaining two cases of extended-nonextended (E-NE) and nonextended-nonextended (NE-NE) dead times. For the three time origins of the counting processes - ordinary, equilibrium, and shifted processes - a set of formulae was newly developed from a general formulation and presented for the event time interval densities, total densities, and exact mean and variance of the counts in a given counting duration. The asymptotic expressions for the mean and variance of the counts, which are most convenient for applications, were fully listed. The equilibrium mean count rates distorted by the three dead times in series were newly derived from the information obtained in these studies. An application of the derived formulae is briefly discussed.

Studies on Efficacy of $Bayvarol^{(R)}$ against Mite(Varroa jacobsoni) and Safety of Bayvarol^{\circledR}$ in Honey Bees (바이바롤(${Bayvarol}^{(R)}$)의 꿀벌응애(Varroa jacobsoni)에 대한 효능 및 꿀벌에 대한 안전성에 관한 연구)

  • Kim, Byeung-gie;Kang, Seung-won
    • Journal of Veterinary Clinics
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    • v.12 no.1
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    • pp.887-896
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    • 1995
  • In order to determine the efficacy of $Bayvarol^{(R)}$ strips(Bayer AG) against the mite Varroa jacobsoni and the safety of $Bayvarol^{(R)}$ strips in honey bees, a series of trials was carried out under field condition in autumn and spring. The results obtained were as follows; 1. The average varroacidal rate of $Bayvarol^{(R)}$ strips was 92.7% in autumn and 93.7% in spring. However the average varroacidal rats of treated control group was 73.8 % in autumn and 75.1 % in spring, and that of untreated control group was 12.1 % in autumn and 16.1 % in spring. 3. The average number of dead bees in $Bayvarol^{(R)}$ group was 13.0 in recommended dosage(RD), 12.3 in 2 times of RD and 14.0 in 4 times of 70 in autumn, and 19.7 in RD,17.0 in 2 times of RD and 19.0 in 4 times of RD in spring. However the average number of dead bees in treated control groups was 38.3 in RD, 62.7 in 2 times of RD and 60.3 in 4 times of RD in autumn and 18.0 in RD, 43.3 in 2 times of RD and 102 in 4 times of RD in spring and that of untreated control of group was 12.7 in autumn and 19.3 in spring. 3. The varroacidal effects and the number of dead bees of all groups were higher in spring than in autumn. 4. It was revealed that $Bayvarol^{(R)}$ were highly saft and effective varroacides for honey bees.

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Use of the Fix and Flap Approach to Complex Open Elbow Injury: The Role of the Free Anterolateral Thigh Flap

  • Chui, Christopher Hoe-Kong;Wong, Chin-Ho;Chew, Winston Y.;Low, Mun-Hon;Tan, Bien-Keem
    • Archives of Plastic Surgery
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    • v.39 no.2
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    • pp.130-136
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    • 2012
  • Background : Complex elbow injuries with associated nerve, muscle, or joint injury commonly develop post-inury stiffness. In order to preserve function, joint congruency, elbow stability and durable wound coverage must be achieved in a timely manner. Methods : A retrospective review of patients who underwent orthopaedic fixation followed by free anterolateral thigh (ALT) flap soft tissue coverage was performed. Five patients were identified and included in this study. Results : We present a series of 5 cases managed with this principle. Soft tissue defects ranged in size from $4{\times}9cm$ ($36cm^2$) to $15{\times}30cm$ ($450cm^2$) and were located either posteriorly (n=4) or anteriorly (n=1). Associated injuries included open fractures (n=3) and motor nerve transection (n=2). Wound coverage was achieved in a mean duration of 18.8 days (range, 11 to 42 day). There were no flap failures and no major complications. The mean postoperative active elbow motion was $102^{\circ}$ (range, $45^{\circ}$ to $140^{\circ}$). Conclusions : In our small series we have highlighted the safety and utility of using the free ALT flap in complex elbow injuries. The ALT flap has many advantages which include abundant skin and subcutaneous tissue; vascularised vastus lateralis muscle that was used in our series to obliterate dead space, provide a vascular bed for nerve grafts and combat infection; and, access to fascia lata grafts for reconstruction of the triceps tendon.

Diagnosis of Submerged Fixed Bioreactor using Radioisotope Tracer (방사성동위원소 추적자를 이용한 침적형 고정 미생물 반응조 진단)

  • Jung, Sunghee;Jin, Joonha;Lee, Myunjoo
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.6
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    • pp.1149-1158
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    • 2000
  • A radioisotope tracer experiment was carried out in the submerged fixed bioreactor of a dye wastewater treatment facility to evaluate the flow behaviors in the 6 compartments of the reactor and to find any possible factors which may affect to the efficiency of the process. Approximately 20mCi of $^{131}I$ was injected into the system as a tracer and 8 radiation detectors were placed in the 6 compartments and at the inlet and the outlet of the system to measure the change of the tracer concentration with time. Using the Perfect Mixers in Series Model the measured data were analyzed to calculate the mean residence time and the characteristic parameters of the flow in the system. The mean residence time of the system was calculated as 17 hours which is 76% of the designed MRT(22.3hr). Among the 6 compartments, the first compartment doesn't show the characteristic of perfect mixer, whereas, the other 5 compartments are working as perfect mixers. The output response of the first compartment is fit well with the simulated output of a model which consists of a perfect mixer with an exchange volume. It indicates that a quarter of the tank volume is working as a dead volume or an exchange volume. From the measured residence time distributions in each compartment, the appropriate sampling times after the change of operational condition of the electron beam accelerator were evaluated.

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Health Assessment by Hematological Studies and Blood chemistries in cultured carps (혈액성상(血液性狀)에 따르는 양식어(養殖魚)의 건강진단(健康診斷))

  • Chun, Seh-Kyu;Oh, Myoung-Joo
    • Journal of fish pathology
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    • v.2 no.1
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    • pp.19-30
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    • 1989
  • The purpose of this study was to obtain the fundamental data for health assessment of cultured fishes. A series of hematological studies and blood chemistries were made on cultured israeli carps from May, 1988 to May, 1989. The results of this study were as followings : 1. The blood constituents of healthy carps were Hct $32{\pm}3.4%$, Hb $8.3{\pm}0.9g/l$, RBCs $132{\pm}27.6({\times}10^4cm^3)$), Total protein $2.7{\pm}0.7g/dl$, GOT $143{\pm}19.5U$, GPT $50{\pm}14.2U$, Total glucose $70{\pm}12.6mg/dl$ and BUN $7.5{\pm}1.9mg/dl$, etc. 2. The blood constituents by change of water temperature with the control of $23^{\circ}C$ showed the decrease in Hct and RBCs at $18^{\circ}C$, and the increase in Hct, RBCs and glucose at $28^{\circ}C$. 3. The blood constituents by change of dissolved oxigen with the control of 4.5ppm showed the increase in Hct and RBCs at 3ppm, and the decrease in Hct and RBCs at 7ppm. 4. In the case of intramuscular injection of Streptococcus sp. with $10^6cells$/fish infection dose, there showed marked decrease in Hct, RBCs, glucose and BUN with inflammatory reaction, and the fishes were recovered in 16 days. 5. In the case on intraperitoneal injection of Streptococcus sp. with $10^4cells$/fish infection dose, there showed decrease in Hct, RBCs and BUN with inflammatory reaction, but there were no dead cases. 6. In the case of intramuscular injection of Edwardsilla tarda with $1.2{\times}10^8cells$/fish infection dose, there showed decrease in Hct and RBCs, and increase in TCHO, GOT, GPT and BUN with marked inflammatory reaction, and 60% of inoculated fishes were died within 3 or 4 days.

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Performance Measurements of Positron Emission Tomography: An Investigation Using General Electric $Advance^{TM}$ (양전자방출단층촬영기의 표준 성능평가 방법: GE $Advance^{TM}$에 적용한 예)

  • Lee, J.R.;Choi, Y.;Choe, Y.S.;Lee, K.H.;Kim, S.E.;Shin, S.A.;Kim, B.T.
    • The Korean Journal of Nuclear Medicine
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    • v.30 no.4
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    • pp.548-559
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    • 1996
  • A series of performance measurements of positron emission tomography (PET) were performed following the recommendations of the Computer and Instrumentation Council of the Society of Nuclear Medicine and the National Electrical Manufacturers Association. We investigated the performance of the General Electric $Advance^{TM}$ PET. The measurements include the basic intrinsic tests of spatial resolution, scatter fraction, sensitivity, and count rate losses and randoms. They also include the tests of the accuracy of corrections: count rate linearity correction, uniformity correction, scatter correction and attenuation correction. GE $Advance^{TM}$ PET has bismuth germanate oxide crystals (4.0mm transaxial ${\times}$ 8.1mm axial ${\times}$ 30.0mm radial) in 18 rings, which form 35 imaging planes spaced by 4.25mm. The system has retractable tungsten septa 1mm thick and 12cm long. Transaxial resolution was 4.92mm FWHM in 2D and 5.14mm FWHM in 3D at the center. Average axial resolution in 2D decreased from 3.91mm FWHM at the center to 6.49mm FWHM at R=20cm. Average scatter fraction of direct and cross slices was 9.57%. Dead-time losses of 50% corresponded to a radioactivity concentration of $4.86{\mu}Ci/cc$ and a true count rate of 519 kcps in 2D. The accuracy of count rate linearity correction was 1.84% at the activity of $4.50{\mu}Ci/cc$. Non-uniformity was 2.06% in 2D and 2.93% in 3D. Remnant errors after scatter correction were 0.55% in 2D and 4.12% in 3D. The errors of attenuation correction were 6.21% (air), 0.20% (water), -6.32% (teflon) in 2D and 5.00% (air), 6.94% (water), 3.01% (teflon) in 3D. The results indicate the performance of GE $Advance^{TM}$ PET scanner to be well suited for clinical and research applications.

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Feasibility Study on Double Path Capacitive Deionization Process for Advanced Wastewater Treatment (이단유로 축전식 탈염공정의 하수고도처리 적용가능성 평가)

  • Cha, Jaehwan;Shin, Kyung-Sook;Lee, Jung-Chul;Park, Seung-Kook;Park, Nam-Su;Song, Eui-Yeol
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.4
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    • pp.295-302
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    • 2014
  • This study demonstrates a double-path CDI as an alternative of advanced wastewater treatment process. While the CDI typically consists of many pairs of electrodes connected in parallel, the new double-path CDI is designed to have series flow path by dividing the module into two stages. The CFD model showed that the double-path had uniform flow distribution with higher velocity and less dead zone compared with the single-path. However, the double-path was predicted to have higher pressure drop(0.7 bar) compared the single-path (0.4 bar). From the unit cell test, the highest TDS removal efficiencies of single- and double-path were up to 88% and 91%, respectively. The rate of increase in pressure drop with an increase of flow rate was higher in double-path than single-path. At 70 mL/min of flow rate, the pressure drop of double-path was 1.67 bar, which was two times higher than single-path. When the electrode spacing was increased from 100 to $200{\mu}m$, the pressure drop of double-path decreased from 1.67 to 0.87 bar, while there was little difference in TDS removal. When proto type double-path CDI was operated using sewage water, TDS, $NH_4{^+}$-N, $NO_3{^-}$-N and $PO_4{^{3-}}$-P removal efficiencies were up to 78%, 50%, 93% and 50%, respectively.