• Title/Summary/Keyword: Response Rates

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Preparation of Polyphosphazene Diagnostic Membranes for Blood Glucose Measurements (혈당측정을 위한 폴리포스파젠 진단막의 제조)

  • Kwon, Suk-Ky
    • Membrane Journal
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    • v.21 no.4
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    • pp.329-335
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    • 2011
  • A new type of diagnostic membranes based on methoxyethoxy and trifluoroethoxy co-substituted polyphosphazene has been prepared to measure blood glucose level of diabetics. Final absorbances at 680 nm through activated polyphosphazene membranes were measured at various concentration of glucose in plasma or blood. The end-point results of varing absorbance values as time (K/S) was found to have a linear relationship toward the blood glucose concentration. The effects of substitution rates with hydrophilic groups and hydrophobic groups on the measurements of glucose concentration were studied. Dose-response slope (DRS) values between glucose concentration and K/S values increased as the hydrophilic substitution rates increased. However, in more than 30% of the substitution rates, it was difficult to measure exact concentration level of glucose because DRS increased rapidly.

Estimating survival distributions for two-stage adaptive treatment strategies: A simulation study

  • Vilakati, Sifiso;Cortese, Giuliana;Dlamini, Thembelihle
    • Communications for Statistical Applications and Methods
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    • v.28 no.5
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    • pp.411-424
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    • 2021
  • Inference following two-stage adaptive designs (also known as two-stage randomization designs) with survival endpoints usually focuses on estimating and comparing survival distributions for the different treatment strategies. The aim is to identify the treatment strategy(ies) that leads to better survival of the patients. The objectives of this study were to assess the performance three commonly cited methods for estimating survival distributions in two-stage randomization designs. We review three non-parametric methods for estimating survival distributions in two-stage adaptive designs and compare their performance using simulation studies. The simulation studies show that the method based on the marginal mean model is badly affected by high censoring rates and response rate. The other two methods which are natural extensions of the Nelson-Aalen estimator and the Kaplan-Meier estimator have similar performance. These two methods yield survival estimates which have less bias and more precise than the marginal mean model even in cases of small sample sizes. The weighted versions of the Nelson-Aalen and the Kaplan-Meier estimators are less affected by high censoring rates and low response rates. The bias of the method based on the marginal mean model increases rapidly with increase in censoring rate compared to the other two methods. We apply the three methods to a leukemia clinical trial dataset and also compare the results.

Asymmetric Relationship between Inflation and Remittance Outflows in Saudi Arabia: A NARDL Approach

  • FOUDEH, Musa;AL-ABDULRAZAG, Bashier
    • The Journal of Asian Finance, Economics and Business
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    • v.10 no.1
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    • pp.79-89
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    • 2023
  • The paper aims to investigate the asymmetric long-run and short-run relationships between inflation and remittance outflows in the Kingdom of Saudi Arabia (hereafter KSA) over the period 1971-2019 by using the Nonlinear Autoregressive Distributed Lag (NARDL) model. The statistical tests have supported the validity and stability of the model. The Wald F-test statistics confirm the existence of a long-run equilibrium relationship among the model variables; remittance outflows, positive (negative) shocks in inflation rates, investment, real GDP, and trade openness. Moreover, the empirical results confirm the existence of an asymmetric effect of the inflation rate on remittance outflows. The response of foreign workers to an increase in inflation rates differs from their response to a decrease in inflation rates. However, this asymmetric relationship between the increases/decreases in inflation and remittance outflows is significantly weak. The weakness of this relationship is due to the high marginal remittance propensity of migrant workers, which is explained by the low consumption propensity of foreign workers and their ability to adjust to the high cost of living due to inflation and the imposition of accompanying fees. Finally, the change in the inflation rate is not among the main factors influencing foreign remittance decisions in Saudi Arabia.

Differential Cytokine and Immunoglobulin Expressions in the Small Intestine of Echinostoma hortense Infected BALB/c Mice

  • Jo, Yoon-Kyung;Lee, Dong-Sup;Kim, Sung-In;Lee, Ji-Sook;Oh, Ji-Eun;Sung, Ho-Joong
    • Biomedical Science Letters
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    • v.18 no.3
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    • pp.254-259
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    • 2012
  • Infections involving Echinostoma hortense (E. hortense) are considered to more severe than infections caused by other heterophyids. Although parasite expulsion by host immune responses attenuates the symptoms of infection, the detailed mechanisms of the host immune response need to be determined, especially in local immune responses involving cytokine and immunoglobulin expressions. We infected BALB/c mice with E. hortense and examined recovery rates together with expressions of multiple cytokines and immunoglobulins in the villi and crypts of the small intestine using immunohistochemistry. We observed a close correlation between worm expulsion rates and cytokine/immunoglobulin expressions in E. hortense infected mice. This study contributes to an understanding of the relationship between the immune response and parasite expulsion in hosts.

A Study on the Logarithmic Counting Ratemeter (대수계수율계에 관한 연구)

  • 이병선;정호균
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.12 no.1
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    • pp.12-17
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    • 1975
  • This paper describes a new simplified logarithmic counting Tatemeter for the measurement of wide range counting rates without selector switch. Theoritical analysis of the proposed circuit and synthesis technique for designing a multi.decade instrument using this configuration are given. It has a linear response on the logarithmic scale for random pulses of Poisson's distribution as well as for periodic pulses. The experimental circuit designed by the proposed technique has a good logarithmic response over 5 decades covering the counting rates from 1 pps to $10^5$ pps. Also the causes of inaccuracy in the low and high range are examined and effestively removed.

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The Infrastructure of Public Opinion Research in Japan

  • Kubota, Yuichi
    • Asian Journal for Public Opinion Research
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    • v.1 no.1
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    • pp.42-60
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    • 2013
  • This article introduces the infrastructure of public opinion research in Japan by reviewing the development of polling organizations and the current situation of social surveys. In Japan, the polling infrastructure developed through the direction and encouragement of the U.S. occupation authorities. In the early 1969s, however, survey researchers began to conduct their own original polls in not only domestic but also cross-national contexts. An exploration of recent survey trends reveals that polling organizations tended to conduct more surveys during summer, in the mid-range of sample size (1,000-2,999), based on random sampling (response rates of 40-50%), and through the mail between April 2011 and March 2012. The media was the most active polling sector.

Comparison of Axial and Radial Flow Chromatography on Protein Separation Speed and Resolution (축방향과 반경방향흐름 크로마토그래피의 단백질 분리속도와 분리능에 대한 비교)

  • 김윤하;이은규
    • KSBB Journal
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    • v.10 no.5
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    • pp.482-490
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    • 1995
  • The relationship between pressure drop and liquid flow rate, for an axial and a radial flow chromatographic column packed with compressible porous media was theoretically analyzed using modified Kozeny-Carman equation. The results were compared with experimental observations obtained using compressible DEAE-agarose as a model medium. At 2-9 psi range studied, the theoretical derivation accounting for 'gel compression' effect predicted simple Langmuirian type response of volumetric flow rate to changes in pressure drop. On the other hand, the experimental response was more or less sigmoidal. At the same pressure drop, radial column showed 2-3 times higher flow rates than those of axial column both theoretically and experimentally. Using r-HBsAg crude extract, protein resolution effects between the two types of columns at different flow rates were compared side-by-side. It turned out that, though general chromatographic behavior was very similar, axial column was somewhat superior in terms of r-HBsAg recovery yield and specificity. However, the number of theoretical plates analysis indicated the protein resolution effects were comparable.

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A Fuzzy Technique-based Web Server Performance Improvement Using a Load Balancing Mechanism (퍼지기법에 기초한 로드분배 방식에 의한 웹서버 성능향상)

  • Park, Bum-Joo;Park, Kie-Jin;Kang, Myeong-Koo;Kim, Sung-Soo
    • Journal of KIISE:Computer Systems and Theory
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    • v.35 no.3
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    • pp.111-119
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    • 2008
  • This paper combines fuzzy concepts with an existing dynamic performance isolation technique in order to improve the response time performance of a Web server supporting differentiated services. A load balancing mechanism based on the fuzzy control technique is developed in such a way that ambiguous situations caused by workload estimation of cluster-based Web servers, client request rates, and dynamic request rates can be represented in an effective way. In addition, we verify that the fuzzy-based performance isolation technique improves the performance and robustness of differentiated service systems efficiently through comparing 95-percentile of response time between the fuzzy-based Performance isolation technique and the existing one, which do not use the fuzzy concept.

Residence Time Distributions of Liquid pbase Flow and Mass Transfers in the Trickle Bed Reactor (점적상 반응기에서 액상흐름의 체류시간 분포 및 물질전달)

  • Kim, Ki-Chang
    • Journal of Industrial Technology
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    • v.6
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    • pp.19-31
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    • 1986
  • The residence time distribution of liquid flow in a 4.0cm diameter column packed with porous $Al_2O_3$ spheres of 0.37cm diameter were measured with pulse injections of a tracer under cocurrent trickling flow conditions. The mean residence time of liquid flow and liquid hold-up calculated by the transient curve of tracer were unaffected by gas flow rates under experimental ranges of liquid flow rates from 2.4 to $4.5(kg/m^2\;sec)$ and gas flow rates from 0 to $0.13(kg/m^2\;sec)$. The axial dispersion coefficient of liquid stream and apparent diffusivity of tracer in a micropore of solid particle were estimated from the response curve of tracer. The calculated Peclet No. were increased in ranges of 68-to 82 with a increasing of liquid mass velocity, and the external effective contacting efficiency between liquid and solid which can be expressed. by $(D_i)_{app}/D_i$ varied in ranges of 0.54 to 0.68 depending on the liquid flow rates. The gas to liquid(water) volumetric mass transfer coefficient were determined from desorption experiments with oxygen at $25^{\circ}C$ and 1 atm. The measured mass transfer coefficients were increased with liquid flow rates and the effect of gas flow rates on the mass transfer coefficient was insignificant.

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Effects of Bank Macroeconomic Indicators on the Stability of the Financial System in Indonesia

  • VIPHINDRARTIN, Sebastiana;ARDHANARI, Margaretha;WILANTARI, Regina Niken;SOMAJI, Rafael Purtomo;ARIANTI, Selvi
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.1
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    • pp.647-654
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    • 2021
  • This study examines the non-performing loans of rural banks and macroeconomic factors in Indonesia, including inflation, exchange rates, and interest rates. Theoretically, the existence of erratic macroeconomic conditions can affect the level of non-performing credit risk in rural credit banks in Indonesia. The effect of macroeconomic conditions on non-performing loans has a different response for each economic sector. The main objective of this study is to determine the effect of macroeconomic factors (inflation, exchange rates, and interest rates) and bank-specific factors (credit) on the Non-Performing Loans (NPL) of Rural Banks in Indonesia for the period from January 2015 to December 2018. This study uses a Vector Error Correction Model (VECM) estimation to determine the effect of independent variables consisting of macroeconomic factors and bank-specific factors. Based on the estimation results of the Vector Error Correction Model, three variables that have a positive and significant effect on long-term non-performing loans are credit, inflation, and interest rates. Meanwhile, in the short term, there are only two variables that have a positive and significant effect on non-performing loans, namely, credit and interest rates. Inflation and exchange rate variables have a negative and insignificant effect on bad credit in the short term.