• Title, Summary, Keyword: Response Rates

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The Effect of Incentives on Internet Surveys: Response Rate Changes After the Introduction of Incentives

  • Kennedy, John M.;Ouimet, Judith A.
    • Asian Journal for Public Opinion Research
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    • v.1 no.2
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    • pp.128-146
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    • 2014
  • Incentives are often included in survey design because they are known to improve response rates, at least moderately. This paper describes the changes in the response rates when incentives were introduced into a longitudinal survey. The National Survey of Student Engagement was conducted annually at Indiana University Bloomington from 2000 through 2012. In 2010, incentives were introduced in an attempt to reverse the declining response rates. The incentives performed as expected, raising the AAPOR Response Rate 3 from 24% in 2009 to 36% in 2010. From 2010 through 2012, different types of incentives were tried but the response rates did not change substantially. The results from the changes in incentives can help survey practitioners decide the number and types of incentives that might be used effectively to increase response rates.

On the SOVA for Extremely High Code Rates over Partial Response Channels

  • Ghrayeb, Ali
    • Journal of Communications and Networks
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    • v.5 no.1
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    • pp.1-6
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    • 2003
  • In this paper, we extend the derivation of the iterative soft-output Viterbi algorithm (SOVA) for partial response (PR) channels, and modify its decoding process such that it works consistently for arbitrary high code rates, e.g., rate 64/65. We show that the modified SOVA always outperforms the conventional SOVA that appears in the literature with a significant difference for high code rates. It also offers a significant cut down in the trace-back computations. We further examine its performance for parallel and serial concatenated codes on a precoded Class IC partial response (PR4) channel. Code rates of the form $\frac{k_0}{k_0+1}$($k_0$ = 4, 8, and 64) are considered. Our simulations indicate that the loss suffered by the modified SOVA, relative to the APP algorithm, is consistent for all code rates and is at most 1.2 dB for parallel concatenations and at most 1.6 dB for serial concatenations at $P_b$ = $10^{-5}$.

A Response Surface Model Based on Absorbance Data for the Growth Rates of Salmonella enterica Serovar Typhimurium as a Function of Temperature, NaCl, and pH

  • Park, Shin-Young;Seo, Kyo-Young;Ha, Sang-Do
    • Journal of Microbiology and Biotechnology
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    • v.17 no.4
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    • pp.644-649
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    • 2007
  • Response surface model was developed for predicting the growth rates of Salmonella enterica sv. Typhimurium in tryptic soy broth (TSB) medium as a function of combined effects of temperature, pH, and NaCl. The TSB containing six different concentrations of NaCl (0, 2, 4, 6, 8, and 10%) was adjusted to an initial of six different pH levels (pH 4, 5, 6, 7, 8, 9, and 10) and incubated at 10 or $20^{\circ}C$. In all experimental variables, the primary growth curves were well $(r^2=0.900\;to\;0.996)$ fitted to a Gompertz equation to obtain growth rates. The secondary response surface model for natural logarithm transformations of growth rates as a function of combined effects of temperature, pH, and NaCl was obtained by SAS's general linear analysis. The predicted growth rates of the S. Typhimurium were generally decreased by basic (9, 10) or acidic (5, 6) pH levels or increase of NaCl concentrations (0-8%). Response surface model was identified as an appropriate secondary model for growth rates on the basis of coefficient determination $(r^2=0.960)$, mean square error (MSE=0.022), bias factor $(B_f=1.023)$, and accuracy factor $(A_f=1.164)$. Therefore, the developed secondary model proved reliable predictions of the combined effect of temperature, NaCl, and pH on growth rates for S. Typhimurium in TSB medium.

Development of Predictive Mathematical Model for the Growth Kinetics of Staphylococcus aureus by Response Surface Model

  • Seo, Kyo-Young;Heo, Sun-Kyung;Lee, Chan;Chung, Duck-Hwa;Kim, Min-Gon;Lee, Kyu-Ho;Kim, Keun-Sung;Bahk, Gyung-Jin;Bae, Dong-Ho;Kim, Kwang-Yup;Kim, Cheorl-Ho;Ha, Sang-Do
    • Journal of Microbiology and Biotechnology
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    • v.17 no.9
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    • pp.1437-1444
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    • 2007
  • A response surface model was developed for predicting the growth rates of Staphylococcus aureus in tryptic soy broth (TSB) medium as a function of combined effects of temperature, pH, and NaCl. The TSB containing six different concentrations of NaCl (0, 2, 4, 6, 8, and 10%) was adjusted to an initial of six different pH levels (pH 4, 5, 6, 7, 8, 9, and 10) and incubated at 10, 20, 30, and $40^{\circ}C$. In all experimental variables, the primary growth curves were well ($r^2=0.9000$ to 0.9975) fitted to a Gompertz equation to obtain growth rates. The secondary response surface model for natural logarithm transformations of growth rates as a function of combined effects of temperature, pH, and NaCl was obtained by SAS's general linear analysis. The predicted growth rates of the S. aureus were generally decreased by basic (pH 9-10) or acidic (pH 5-6) conditions and higher NaCl concentrations. The response surface model was identified as an appropriate secondary model for growth rates on the basis of correlation coefficient (r=0.9703), determination coefficient ($r^2=0.9415$), mean square error (MSE=0.0185), bias factor ($B_f=1.0216$), and accuracy factor ($A_f=1.2583$). Therefore, the developed secondary model proved reliable for predictions of the combined effect of temperature, NaCl, and pH on growth rates for S. aureus in TSB medium.

Impaired Response Inhibition in Patients with Obsessive-Compulsive Disorder (강박장애 환자의 반응억제 결함)

  • Boo, Young Jun;Kim, Se Joo;Kang, Jee In
    • Anxiety and mood
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    • v.11 no.1
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    • pp.33-37
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    • 2015
  • Objective : Impaired response inhibition has been suggested to play an important role in the pathophysiology of obsessive-compulsive disorder (OCD). The aim of this study was to evaluate the response inhibition in patients with OCD, by using the Go/NoGo paradigm, and to better understand its associations with clinical symptoms. Methods : The participants included 63 OCD patients and 80 healthy volunteers matched in age and sex. response inhibition was evaluated using computerized Go/NoGo task, in which their commission error rates, omission error rates, and mean response times were measured. The severity of clinical symptoms in the OCD patients was assessed using Montgomery-Asberg Depression Scale and Yale-Brown Obsessive Compulsive Scale. Result : OCD patients showed significantly impaired inhibition and higher omission errors rates despite their slower response time, compared to normal controls. Clinical symptoms were not correlated with commission errors and omission errors. Conclusion : The present results indicate that impairment in response inhibition may play a critical role in the pathophysiology of OCD as a trait. These findings suggest that deficit of response inhibition may contribute to developing and maintaining clinical symptoms such as compelling need to repeat certain actions in patients with OCD.

Response Rate and Community Context: Comparison of U.S. Census and the General Social Survey (사회조사 응답률에 영향을 미치는 지역의 경제.사회적 요인: 2000년 미국 센서스와 2002년 미국 종합사회조사 비교)

  • Kim, Ji-Bum;Oh, Mi-Hye;Kang, Jeong-Han
    • Survey Research
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    • v.11 no.3
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    • pp.1-18
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    • 2010
  • How much do people living in different communities vary in their survey responses? A few studies have examined the effect of the social environment on survey response. Making generalizations from these studies by looking at the effect of social environment on survey response is complicated due to differences in survey dimensions, including incentives, survey mode, types of response rates, and geographic levels. Using the 2000 Census Final Response Rates(CFRR) and the 2002 General Social Survey Response Rates(GSSRR) linked with the 2000 Census in the United States, we attempt to understand how community characteristics associated with survey cooperation vary between data sets. We found that people living in poor area are less likely to cooperate with the Census but more likely to cooperate with GSS, while people living in an area with more minors under 18 is more likely to cooperate with both Census and the GSS. By using two data sources with contrasting survey dimensions within the United States, our findings have implications for survey field operations and hopefully will invigorate studies about response rates in a Korean context.

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Viscoplastic response and collapse of 316L stainless steel tubes under cyclic bending

  • Chang, Kao-Hua;Hsu, Chien-Min;Sheu, Shane-Rong;Pan, Wen-Fung
    • Steel and Composite Structures
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    • v.5 no.5
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    • pp.359-374
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    • 2005
  • This paper presents the experimental and theoretical results of the viscoplastic response and collapse of 316L stainless steel tubes subjected to cyclic bending. The tube bending machine and curvature-ovalization measurement apparatus, which was designed by Pan et al. (1998), were used for conducting the cyclic curvature-controlled experiment. Three different curvature-rates were controlled to highlight the characteristic of viscoplastic response and collapse. Next, the endochronic theory and the principle of virtual work were used to simulate the viscoplastic response of 316L stainless steel tubes under cyclic bending. In addition, a proposed theoretical formulation (Lee and Pan 2001) was used to simulate the relationship between the controlled cyclic curvature and the number of cycles to produce buckling under cyclic bending at different curvature-rates (viscoplastic collapse). It has been shown that the theoretical simulations of the response and collapse correlate well with the experimental data.

Similarity between a stagnant point diffusion flame and an evolving jet diffusion flame (전개확산제트화염과 정체점 확산화염과의 유사성)

  • Park, Jeong;Shin, Hyun-Dong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.21 no.4
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    • pp.494-502
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    • 1997
  • Experiments on corresponding jet flames with stagnant point diffusion flames have been carried out in initial injection periods. A compensated measurement of maximum flame temperature, which is based on the ion signal, has been employed to inspect flame responses to time-varying strain rates. The flame responses are obtained at two conditions for the slowly time-varying strain rate and the case of flame extinction, and analyzed to confirm similarity between a stagnant point diffusion flame and an evolving jet diffusion flame. Nonsteady effects are addressed via the comparison between several time scales. The time variation with low strain rates, in which illustrates the flame behavior of the upper branch far from extinction in the well-known S-curve, is confirmed to produce a quasi-steady flame response through the nonsteady experiments. The time variation with strain rates in the case of flame extinction indicates an unsteady effect of flame response. It is therefore found that the flame responses near jet tip depend on time histories of characterized strain rates in the developing process.

Demand Response of Large-Scale General and Industrial Customer using In-House Pricing Model (사내요금제를 활용한 대규모 수용가 수요반응에 관한 연구)

  • Kim, Min-Jeong
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.7
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    • pp.1128-1134
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    • 2016
  • Demand response provides customer load reductions based on high market prices or system reliability conditions. One type of demand response, price-based program, induces customers to respond to changes in product rates. However, there are large-scale general and industrial customers that have difficulty changing their energy consumption patterns, even with rate changes, due to their electricity demands being commercial and industrial. This study proposes an in-house pricing model for large-scale general and industrial customers, particularly those with multiple business facilities, for self-regulating demand-side management and cost reduction. The in-house pricing model charges higher rates to customers with lower load factors by employing peak to off-peak ratios in order to reduce maximum demand at each facility. The proposed scheme has been applied to real world and its benefits are demonstrated through an example.

Study on Spawning Induction and Larvae Breeding of the Hard Clam, Meretrix petechiails (Lamarck) (말백합, Meretrix petechiails (Lamarck) 의 산란유발 및 유생사육에 관한 연구)

  • Kim, Byeong-Hak;Moon, Tae-Seok;Park, Ki-Yeol;Jo, Pil-Gue;Kim, Min-Chul
    • The Korean Journal of Malacology
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    • v.26 no.2
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    • pp.151-156
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    • 2010
  • For industrialization of the hard clams, Meretrix petechiails (Lamarck), spawning was induced per spawning induction technique in the artificial maturation group administered of parent maturation control and the natural maturation group of which parents were transported for artificial spawning per time period. Then, fertilization rates, hatching rates and D-shaped larva development rates were investigated. In addition, growth and survival rates of larvae were investigated per larva breeding technique. The results of spawning induction by exposure in the artificial maturation group indicated that response rates were relatively higher at 23% and 32% respectively at the 4th hour and the 8th hour of exposure. In terms of water temperature increase, responses began only when the temperature reached $28^{\circ}C$ or higher. In the experiment group administered with both exposure and water temperature increase techniques, response rate was found to be 45% or higher at the 4th hour of exposure and the temperature of $28^{\circ}C$. At the temperatures of 29, 30 and $31^{\circ}C$, significant differences were not observed. Therefore, it was indicated that the response rates of parent hard clams were higher toward water temperature increase than exposure time. As for spawning induction per time period of the transported parent group, response rate and D-shaped larva development rate were the highest at 67.6% and 96% respectively on August 6, 2009. In terms of water temperatures during larva breeding experiment, growth was faster as water temperature was higher. In addition, growth and survival rates were relatively higher at the salinity of 25. In terms of stocking density, growth and survival rates were relatively higher at 5 inds./mL.