Статті в журналах з теми "Confounded symmetrical factorial design"
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1
KUMAR, PRAKASH, KRISHAN LAL, ANIRBAN MUKHERJEE, UPENDRA KUMAR PRADHAN, MRINMOY RAY, and OM PRAKASH. "Advanced row-column designs for animal feed experiments." Indian Journal of Animal Sciences 88, no. 4 (January 5, 2023): 499–503. http://dx.doi.org/10.56093/ijans.v88i4.78895.
Повний текст джерелаАнотація:
Inappropriate statistical designs may misinterpret results of animal feed experiments. Thus complete statistical designs can make animal feed research more appropriate and cost effective. Usually factorial row-column designs are used when the heterogeneity in the experimental material is in two directions and the experimenter is interested in studying the effect of two or more factors simultaneously. Attempts have been to develop the method of construction of balanced nested row column design under factorial setup. Factorial experiments are used in designs when two or more factors have same levels or different levels. The designs that are balanced symmetric factorials nested in blocks are called block designs with nested row-column balanced symmetric factorial experiments. These designs were constructed by using confounding through equation methods.Construction of confounded asymmetrical factorial experiments in row-column settings and efficiency factor of confounded effects was worked out. The design can be used in animal feed experiment with fewer resources by not compromising the test accuracy.
2
Das, Dipa Rani, and Sanjib Ghosh. "An Alternative Method of Construction and Analysis of Asymmetrical Factorial Experiment of the type 6x22 in Blocks of Size 12." Chittagong University Journal of Science 40, no. 1 (June 28, 2018): 137–50. http://dx.doi.org/10.3329/cujs.v40i1.47920.
Повний текст джерелаАнотація:
This paper focuses on the construction and analysis of an extra ordinary type of asymmetrical factorial experiment which corresponds to fraction of a symmetrical factorial experiment as indicated by Das (1960). For constructing this design, we have used 3 choices and for each choice we have used 5 different cases. Finding the block contents for each case we have seen that there are mainly two different cases for each choice. In case of analysis of variance, we have seen that, for the case where the highest order interaction effect is confounded in 4 replications, the loss of information is same for all the choices. Again for the case where the highest order interaction effect is confounded in 3 replications, the loss of information is also same for all the choices and one effect which is confounded due to fractionation has the same loss of information for all the choices.
The Chittagong Univ. J. Sci. 40 : 137-150, 2018
3
Dülmer, Hermann. "The Factorial Survey." Sociological Methods & Research 45, no. 2 (April 27, 2015): 304–47. http://dx.doi.org/10.1177/0049124115582269.
Повний текст джерелаАнотація:
The factorial survey is an experimental design consisting of varying situations (vignettes) that have to be judged by respondents. For more complex research questions, it quickly becomes impossible for an individual respondent to judge all vignettes. To overcome this problem, random designs are recommended most of the time, whereas quota designs are not discussed at all. First comparisons of random designs with fractional factorial and D-efficient designs are based on fictitious data, first comparisons with fractional factorial and confounded factorial designs are restricted to theoretical considerations. The aim of this contribution is to compare different designs regarding their reliability and their internal validity. The benchmark for the empirical comparison is established by the estimators from a parsimonious full factorial design, each answered by a sample of 132 students (real instead of fictitious data). Multilevel analyses confirm that, if they exist, balanced confounded factorial designs are ideal. A confounded D-efficient design, as proposed for the first time in this article, is also superior to simple random designs.
4
Weimer, Jon. "Confounded Experimental Designs and Human Factors Research." Proceedings of the Human Factors Society Annual Meeting 31, no. 2 (September 1987): 222–23. http://dx.doi.org/10.1177/154193128703100219.
Повний текст джерелаАнотація:
The use of confounded factorial designs has been seriously neglected in the human factors literature. A confounded factorial is constructed by systematically confounding blocking variables with one or more interactions which are believed to be statistically insignificant or inconsequential to the researcher. These designs offer the advantages of increased economy and power. These designs are especially useful when research is being conducted on military personnel and subjects must be selected from different military facilities, which may result in heterogeneous subject populations. A concrete example illustrates how confounding of this type can be used to the researcher's advantage through the tailored construction of a confounded design.
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C. Eze, Francis. "Choice of Confounding in the 2k Factorial Design in 2b Blocks." Academic Journal of Applied Mathematical Sciences, no. 55 (May 15, 2019): 50–56. http://dx.doi.org/10.32861/ajams.55.50.56.
Повний текст джерелаАнотація:
In 2k complete factorial experiment, the experiment must be carried out in a completely randomized design. When the numbers of factors increase, the number of treatment combinations increase and it is not possible to accommodate all these treatment combinations in one homogeneous block. In this case, confounding in more than one incomplete block becomes necessary. In this paper, we considered the choice of confounding when k > 2. Our findings show that the choice of confounding depends on the number of factors, the number of blocks and their sizes. When two more interactions are to be confounded, their product module 2 should be considered and thereafter, a linear combination equation should be used in allocating the treatment effects in the principal block. Other contents in other blocks are generated by multiplication module 2 of the effects not in the principal block. Partial confounding is recommended for the interactions that cannot be confounded.
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Khan, Md Kamrul Hasan, and MA Jalil. "A General Method of Constructing Layout with Single Factorial Effect Confounded in pn Factorial Experiments." Dhaka University Journal of Science 62, no. 2 (February 8, 2015): 109–13. http://dx.doi.org/10.3329/dujs.v62i2.21974.
Повний текст джерелаАнотація:
A general method of constructing layout with single factorial effect confounded in pn factorial experiments is proposed. It becomes easier to construct the design of confounding a single factor in a pn factorial experiment, especially when the number of factors as well as the number of levels becomes larger. DOI: http://dx.doi.org/10.3329/dujs.v62i2.21974 Dhaka Univ. J. Sci. 62(2): 109-113, 2014 (July)
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Atzmüller, Christiane, and Peter M. Steiner. "Experimental Vignette Studies in Survey Research." Methodology 6, no. 3 (January 2010): 128–38. http://dx.doi.org/10.1027/1614-2241/a000014.
Повний текст джерелаАнотація:
Vignette studies use short descriptions of situations or persons (vignettes) that are usually shown to respondents within surveys in order to elicit their judgments about these scenarios. By systematically varying the levels of theoretically important vignette characteristics a large population of different vignettes is typically available – too large to be presented to each respondent. Therefore, each respondent gets only a subset of vignettes. These subsets may either be randomly selected in following the tradition of the factorial survey or systematically selected according to an experimental design. We show that these strategies in selecting vignette sets have strong implications for the analysis and interpretation of vignette data. Random selection strategies result in a random confounding of effects and heavily rely on the assumption of no interaction effects. In contrast, experimental strategies systematically confound interaction effects with main or set effects, thereby preserving a meaningful interpretation of main and important interaction effects. Using a pilot study on attitudes toward immigrants we demonstrate the implementation and analysis of a confounded factorial design.
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Luis Pérez, Carmelo J. "On the Application of a Design of Experiments along with an ANFIS and a Desirability Function to Model Response Variables." Symmetry 13, no. 5 (May 18, 2021): 897. http://dx.doi.org/10.3390/sym13050897.
Повний текст джерелаАнотація:
In manufacturing engineering, it is common to use both symmetrical and asymmetrical factorial designs along with regression techniques to model technological response variables, since the in-advance prediction of their behavior is of great importance to determine the levels of variation that lead to optimal response values to be obtained. For this purpose, regression techniques based on the response surface method combined with a desirability function for multi-objective optimization are commonly employed, since it is usual to find manufacturing processes that require simultaneous optimization of several variables, which exhibit in many cases an opposite behavior. However, these regression models are sometimes not accurate enough to predict the behavior of these response variables, especially when they have significant non-linearities. To deal with this drawback, soft computing techniques are very effective in overcoming the limitations of conventional regression models. This present study is focused on the employment of a symmetrical design of experiments along with a new desirability function, which is proposed in this study, and with soft computing techniques based on fuzzy logic. It will be shown that more accurate results than those obtained from regression techniques are obtained. Moreover, this new desirability function is analyzed in this study.
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Judge, Kevin A., Kim-Chi Tran, and Darryl T. Gwynne. "The relative effects of mating status and age on the mating behaviour of female field crickets." Canadian Journal of Zoology 88, no. 2 (February 2010): 219–23. http://dx.doi.org/10.1139/z09-139.
Повний текст джерелаАнотація:
Intrinsic factors such as female age and mating status have been found to affect female choosiness. However, as these factors are often confounded in the wild because mated females are usually older individuals, the relative influence of these two factors on female behaviour is unclear. Using a fully factorial design, we tested the relative effects of age and mating status of female field crickets ( Gryllus pennsylvanicus Burmeister, 1838) on both (i) the probability that she would mate and (ii) her latency to mate. We found that virgin females were both more likely to mate and copulated more quickly than mated females, but female age had no significant effect on either the probability of mating or the latency to copulate. These results clearly show that mating status is more important in determining female mating behaviour than age. We suggest that previous work which showed an age effect on female choosiness in virgins alone might be of reduced relevance if most females do not remain unmated for long.
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Kulaz, Haluk, Solmaz Najafi, Murat Tuncturk, Ruveyde Tuncturk, and Hilal Yilmaz. "Chromosome analysis of some Phaseolus vulgaris L. genotypes in Turkey." Bangladesh Journal of Botany 51, no. 2 (June 28, 2022): 281–88. http://dx.doi.org/10.3329/bjb.v51i2.60425.
Повний текст джерелаАнотація:
Karyotypes parameters in four selected Turkish bean genotypes (BT, HK, VN, and EL) were studied. Genotypes (4 levels) and chromosomes (11 levels) were compared in factorial experiment based on completely randomized design with five replications. Genotypes showed significant differences in long arm, short arm and total chromosome length and divided into three separate groups. Genotypes BL and HK were placed together in a separate group, probably showing the weaker kinship with the other genotypes. Also, the significant differences in all recorded parameters were observed among chromosomes of each genotype. All genotypes were diploid 2n = 22 with no satellite and differed significantly in karyotypic parameters. The most and the least chromatin length (34.24 μm and 15.65 μm) were observed in BT and EL genotypes, respectively. Also, all genotypes showed high chromosomal symmetry and categorized in Stebbins's Class 1A. The karyotype of genotype BT was found to be more symmetrical than others. Bangladesh J. Bot. 51(2): 281-288, 2022 (June)
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Batali, Mackenzie E., Lik Xian Lim, Jiexin Liang, Sara E. Yeager, Ashley N. Thompson, Juliet Han, William D. Ristenpart, and Jean-Xavier Guinard. "Sensory Analysis of Full Immersion Coffee: Cold Brew Is More Floral, and Less Bitter, Sour, and Rubbery Than Hot Brew." Foods 11, no. 16 (August 13, 2022): 2440. http://dx.doi.org/10.3390/foods11162440.
Повний текст джерелаАнотація:
Cold brew coffee is often described as sweeter or less acidic than hot brew coffee. Such comparisons, however, are potentially confounded by two key effects: different brew temperatures necessarily change the extraction dynamics and potentially alter the resulting brew strength, and different consumption temperatures are well known to affect perceived flavor and taste. Here, we performed a systematic study of how extraction temperature affects the sensory qualities of full immersion coffee. The investigation used a 3 × 3 × 3 factorial design, with coffee from three different origins representing different post-harvest methods (washed, honey-processed, and wet-hulled), each roasted to three different levels (light, medium, and dark), and each brewed at three different temperatures (4 °C, 22 °C, and 92 °C). All coffees were brewed to equilibrium, then diluted to precisely 2% total dissolved solids (TDS) and served at the same cold temperature (4 °C). We find that four attributes exhibited statistically significant variations with brew temperature for all origins and roast levels tested, with bitter taste, sour taste, and rubber flavor all higher in hot brewed coffees, and floral flavor higher in cold brewed coffee. However, there were strong interactions with origin and roast, with several additional attributes significantly impacted by temperature for specific origins and roast levels. These results provide insight on how brew temperature can be used to modulate the flavor profile of full immersion coffee.
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Chebat, Jean-Charles, Claire Gelinas-Chebat, and Pierre Filiatrault. "Interactive Effects of Musical and Visual Cues on Time Perception: An Application to Waiting Lines in Banks." Perceptual and Motor Skills 77, no. 3 (December 1993): 995–1020. http://dx.doi.org/10.2466/pms.1993.77.3.995.
Повний текст джерелаАнотація:
This study explores the interactive effects of musical and visual cues on time perception in a specific situation, that of waiting in a bank. Videotapes are employed to simulate the situation; a 2 × 3 factorial design ( N = 427) is used: 2 (high vs low) amounts of visual information and 2 (fast vs slow) levels of musical tempo in addition to a no-music condition. Two mediating variables are tested in the relation between the independent variables (musical and visual ones) and the dependent variable (perceived waiting time), mood and attention. Results of multivariate analysis of variance and a system of simultaneous equations show that musical cues and visual cues have no symmetrical effects: the musical tempo has a global (moderating) effect on the whole structure of the relations between dependent, independent, and mediating variables but has no direct influence on time perception. The visual cues affect time perception, the significance of which depends on musical tempo. Also, the “Resource Allocation Model of Time Estimation” predicts the attention-time relation better than Ornstein's “storage-size theory.” Mood state serves as a substitute for time information with slow music, but its effects are cancelled with fast music.
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Whiting, James R., and Bonnie A. Fraser. "Contingent Convergence: The Ability To Detect Convergent Genomic Evolution Is Dependent on Population Size and Migration." G3: Genes|Genomes|Genetics 10, no. 2 (December 23, 2019): 677–93. http://dx.doi.org/10.1534/g3.119.400970.
Повний текст джерелаАнотація:
Outlier scans, in which the genome is scanned for signatures of selection, have become a prominent tool in studies of local adaptation, and more recently studies of genetic convergence in natural populations. However, such methods have the potential to be confounded by features of demographic history, such as population size and migration, which are considerably varied across natural populations. In this study, we use forward-simulations to investigate and illustrate how several measures of genetic differentiation commonly used in outlier scans (FST, DXY and Δπ) are influenced by demographic variation across multiple sampling generations. In a factorial design with 16 treatments, we manipulate the presence/absence of founding bottlenecks (N of founding individuals), prolonged bottlenecks (proportional size of diverging population) and migration rate between two populations with ancestral and diverged phenotypic optima. Our results illustrate known constraints of individual measures associated with reduced population size and a lack of migration; but notably we demonstrate how relationships between measures are similarly dependent on these features of demography. We find that false-positive signals of convergent evolution (the same simulated outliers detected in independent treatments) are attainable as a product of similar population size and migration treatments (particularly for DXY), and that outliers across different measures (for e.g., FST and DXY) can occur with little influence of selection. Taken together, we show how underappreciated, yet quantifiable measures of demographic history can influence commonly employed methods for detecting selection.
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Simovic, L., and J. P. Jones. "Removal of Organic Micropollutants from Contaminated Groundwater by Oxidation and Stripping." Water Quality Research Journal 22, no. 1 (February 1, 1987): 187–96. http://dx.doi.org/10.2166/wqrj.1987.014.
Повний текст джерелаАнотація:
Abstract In 1984, Environment Canada carried out a bench scale study on the removal of organic micropollutants from contaminated groundwater. The groundwater samples were obtained from the Special Waste Compound at Gloucester Landfill Site, near Ottawa, Ontario. The objective of the study was to evaluate the effectiveness of chemical oxidation to destroy the organic micropollutants present in this groundwater. Comparison was made between the results of ozonation and the air stripping effects. The oxidants evaluated were ozone (O3), sodium hypochlorite (NaOCl), chlorine dioxide (ClO2) and hydrogen peroxide (H2O2) with hydrated iron sulphate FeSO4 7H2O (Fenton’s reagent). The organics present in the contaminated groundwater included the following, predominantly volatile, compounds: bromodichloro-methane, bromoform, 1,1,1-trichloroethane, chloroform, 1,1-dichloroethane, dichloromethane, 1,2-dichloroethane, 1,1-dichloroethylene, and trichloroethylene. The process variables investigated were pH and oxidant dosage. The significance of low and high values of these variables was examined by using a full 22 factorial design. From the results, it appeared that the best removal efficiency was achieved by using ozone as an oxidant. However, during the experiments, it was observed that the ozonation process was being confounded with the air stripping process. Chlorine dioxide and hydrogen peroxide, in that order, were determined to be less effective oxidants. Sodium hypochlorite was found to be the least effective oxidant in this study. The results of this study demonstrated that air stripping was the most appropriate technology for the removal of the organic compounds from this groundwater.
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Hernandez-Ortega, Blanca. "Not so positive, please!" Internet Research 29, no. 4 (August 5, 2019): 606–37. http://dx.doi.org/10.1108/intr-07-2017-0257.
Повний текст джерелаАнотація:
Purpose The purpose of this paper is to analyse the effect of positive online consumer reviews (OCRs) on changes in the individual’s evaluations from the pre-purchase to the post-consumption stage, studying satisfaction, attitude towards the firm and purchase intention. The effect of positive OCRs may differ depending on whether the product performance is high or low, i.e., whether the product meets the objectives of the consumer. So, the paper also explores different effects that positive OCRs can have on changes in the individual’s evaluations depending on the kind of performance. Design/methodology/approach Two studies based on the experimental methodology are carried out and several statistical techniques are applied: confirmatory factorial analysis, mixed between-within subjects analysis of variance and post-hoc analysis. Findings Results demonstrate that the effect of positive OCRs continues after consumption. Depending on the performance, this effect can be positive (negative) and verify (contrast with) the individual’s pre-purchase evaluations. Moreover, this effect is always more intense when the performance is low. Originality/value It explores the changes in the individual’s evaluations about the product and the firm, going beyond the immediate effect of positive OCRs. It also explains the effects of positive OCRs for high and low performance. Finally, it demonstrates that OCR effects are not symmetrical for high and low performance.
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Amodu, Temitope Adebisi, Ayodele Osisanya, Oluseyi Akintunde Dada, Janet Sunday Petters, Margaret Okwuonu Uzor, Francis Kibai Sarimiye, Andrew Oghenerukevwe Orovwigho, et al. "Effect of Oral Placement and Expressive Therapies on Speech Intelligibility of Adolescents with Articulation Disorder." Journal of Intellectual Disability - Diagnosis and Treatment 10, no. 3 (July 15, 2022): 130–37. http://dx.doi.org/10.6000/2292-2598.2022.10.03.2.
Повний текст джерелаАнотація:
Intelligible speech is vital to every adolescent's life, but this skill can be confounded with the presence of articulation disorder. Meanwhile, studies have been conducted using different therapies to improve speech intelligibility. This study investigated the effect of oral placement and expressive therapies on speech intelligibility among adolescents with articulation disorders.
The study adopted a pretest-posttest, control group, quasi-experimental research design with a 3x2x2 factorial matrix. Three special centers were randomly selected, and purposive sampling was used in selecting 60 adolescents having articulation disorders comprising 34 males and 26 females. These adolescents were randomly assigned to Experimental Group 1 (n= 22), Experimental Group 2 (n= 21), and Control (n= 17). Speech Intelligibility Assessment Scale (r=0.92) was the instrument used for the study. Participants in the experimental groups were exposed to the oral placement and expressive therapeutic treatments, while those in the control groups were sensitized to a placebo. Three hypotheses were tested at a 0.05 level of significance, while data were analyzed using Analysis of Covariance (ANCOVA), mean scores, and Bonferroni Post Hoc Test.
Findings revealed that there was a significant main effect of treatments F(2,56) = 112.52; p <0.05 (oral placement therapy, expressive therapy, and control group with placebo), and also a significant interaction effect of treatments, gender, and age F(2, 47) = 7.37; p <0.05 on speech intelligibility of adolescents with articulation disorders despite the presence of placebo. Oral placement and expressive therapies were effective in managing the speech intelligibility of adolescents with articulation disorders.
Therefore, speech therapists should adopt these therapeutic interventions in rehabilitating adolescents with articulation disorders.
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Kuk, Francis, and Denise Keenan. "Efficacy of a Reverse Cardioid Directional Microphone." Journal of the American Academy of Audiology 23, no. 01 (January 2012): 064–73. http://dx.doi.org/10.3766/jaaa.23.1.7.
Повний текст джерелаАнотація:
Background: Directional microphones have been shown to improve a listener's ability to communicate in noise by improving the signal to noise ratio. However, their efficacy may be questioned in situations where the listener needs to understand speech originating from the back. Purpose: The goal of the study was to examine the performance of a directional microphone mode that has an automatic reverse cardioid polar pattern. Research Design: A single-blinded, factorial repeated-measures design was used to study the effect of microphone modes (reverse cardioid, omnidirectional, and front hypercardioid) and stimulus azimuths (front and back) on three outcome variables (aided thresholds, nonsense syllable identification in quiet, and sentence recognition in noise). Study Sample: Twenty adults with a mild-to-severe bilaterally symmetrical (±5 dB) sensorineural hearing loss participated. Intervention: Audibility in quiet was evaluated by obtaining aided sound field thresholds and speech identification at an input level of 50 dB SPL presented at 0 and 180° azimuths. In addition, speech understanding in noise was also assessed with the Hearing In Noise Test (HINT) sentences presented at both azimuths (0 and 180°) with a diffuse noise. Data Collection and Analysis: Repeated-measures analyses of variance (ANOVAs) were conducted to examine the effects of microphone mode (omnidirectional, front hypercardioid, reverse cardioid) and stimulus azimuth (0°, 180°) on aided thresholds, nonsense syllable identification, and HINT performance. Results: Results with the reverse cardioid directional microphone in both quiet conditions were similar to the omnidirectional microphone. The results of the reverse cardioid microphone in noise were significantly better than the omnidirectional microphone and front hypercardioid microphone when speech was presented from the back (p < 0.001). Conclusions: These results support the possible benefits of a reverse cardioid directional microphone when used in specific listening situations.
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Aziz, Nasuhar Ab, and Habshah Midi. "Penalty Function Optimization in Dual Response Surfaces Based on Decision Maker’s Preference and Its Application to Real Data." Symmetry 14, no. 3 (March 17, 2022): 601. http://dx.doi.org/10.3390/sym14030601.
Повний текст джерелаАнотація:
The dual response surface methodology is a widely used technique in industrial engineering for simultaneously optimizing both the process mean and process standard deviation functions of the response variables. Many optimization techniques have been proposed to optimize the two fitted response surface functions that include the penalty function method (PM). The PM method has been shown to be more efficient than some existing methods. However, the drawback of the PM method is that it does not have a specific rule for determining the penalty constant; thus, in practice, practitioners will find this method difficult since it depends on subjective judgments. Moreover, in most dual response optimization methods, the sample mean and sample standard deviation of the response often use non-outlier-resistant estimators. The ordinary least squares (OLS) method is also usually used to estimate the parameters of the process mean and process standard deviation functions. Nevertheless, not many statistics practitioners are aware that the OLS procedure and the classical sample mean and sample standard deviation are easily influenced by the presence of outliers. Alternatively, instead of using those classical methods, we propose using a high breakdown and highly efficient robust MM-mean, robust MM-standard deviation, and robust MM regression estimators to overcome these shortcomings. We also propose a new optimization technique that incorporates a systematic method to determine the penalty constant. We call this method the penalty function method based on the decision maker’s (DM) preference structure in obtaining the penalty constant, denoted as PMDM. The performance of our proposed method is investigated by a Monte Carlo simulation study and real examples that employ symmetrical factorial design of experiments (DOE). The results signify that our proposed PMDM method is the most efficient method compared to the other commonly used methods in this study.
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Buj-Corral, Irene, Xavier Sánchez-Casas, and Carmelo J. Luis-Pérez. "Analysis of AM Parameters on Surface Roughness Obtained in PLA Parts Printed with FFF Technology." Polymers 13, no. 14 (July 20, 2021): 2384. http://dx.doi.org/10.3390/polym13142384.
Повний текст джерелаАнотація:
Fused filament fabrication (FFF) 3D printing technology allows very complex parts to be obtained at a relatively low cost and in reduced manufacturing times. In the present work, the effect of main 3D printing parameters on roughness obtained in curved surfaces is addressed. Polylactic acid (PLA) hemispherical cups were printed with a shape similar to that of the acetabular part of the hip prostheses. Different experiments were performed according to a factorial design of experiments, with nozzle diameter, temperature, layer height, print speed and extrusion multiplier as variables. Different roughness parameters were measured—Ra, Rz, Rku, Rsk—both on the outer surface and on the inner surface of the parts. Arithmetical mean roughness value Ra and greatest height of the roughness profile Rz are usually employed to compare the surface finish among different manufacturing processes. However, they do not provide information about the shape of the roughness profile. For this purpose, in the present work kurtosis Rku and skewness Rsk were used. If the height distribution in a roughness profile follows a normal law, the Rku parameter will take a value of 3. If the profile distribution is symmetrical, the Rsk parameter will take a value of 0. Adaptive neural fuzzy inference system (ANFIS) models were obtained for each response. Such models are often employed to model different manufacturing processes, but their use has not yet been extended to 3D printing processes. All roughness parameters studied depended mainly on layer height, followed by nozzle diameter. In the present work, as a general trend, Rsk was close to but lower than 0, while Rku was slightly lower than 3. This corresponds to slightly higher valleys than peaks, with a rounded height distribution to some degree.
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Jitsamruay, Sangtawan, Ronnason Chinram, Kittisak Poolyarat, and Thammarat Panityakul. "An Application of Six Sigma for Optimality of Medium Density Fiberboard Production." International Journal of Analysis and Applications 21 (March 13, 2023): 22. http://dx.doi.org/10.28924/2291-8639-21-2023-22.
Повний текст джерелаАнотація:
During the production process of MDF, there is a high level of internal bond (IB) variation. This results in the waste of out-of-standard IB values that account for 0.38 % with damage value over 1 million baht/year. The company required products with fewer volatile compounds from formaldehyde adhesives, focusing on reducing the amount of adhesive but still being strong according to IB-specification which will reduce the cost of production by about 20 − 30 million baht/year. The results of wood sampling and IB testing were divided into 6 areas, namely IB1-IB6. It was found that most of the data were symmetrical except for the IB5 data as the area where the most variation occurs. The distributions of the IB1 and IB6 data showed relatively low variability compared to data from other areas. IB1 - IB6 values were normal distribution, expect for IB5. Process capacity in IB2 was relatively high compared to IB from other areas. From the Correlation Matrix and Correlation Map, it was found that the variables that influenced the IB were Press Factor, % Dosing Glue, Heat Circuit1, Primary Circuit Intel and % Mc After Gluing. To conduct the experiment and find the best variable conditions by 25-2 - Factorial Design (Resolution: III). It was found that Glue = 7.4, Heat1 = 234.4, and Press = 6.5 would give IB = 0.88 which was closest to target (0.7). Glue = 7.1, Heat1 = 233.2, and Press = 6.48 would give IB = 1.15 which was the highest value. Results of production conditions at optimum or maximum that can be generalized from Rayleigh Method Dimensional Analysis was found that at the levels of 7.85, 254.28 and 257.70 of Glue, Heat1 and PrimCirIn, the target response (IB) was 0.7. and at the levels of 8.07, 233.35 and 281.60 of Glue, Heat1 and PrimCirIn resulted in a response value (IB) of 1.27.
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Kuk, Francis, Chi-chuen Lau, Petri Korhonen, and Bryan Crose. "Speech Intelligibility Benefits of Hearing Aids at Various Input Levels." Journal of the American Academy of Audiology 26, no. 03 (March 2015): 275–88. http://dx.doi.org/10.3766/jaaa.26.3.7.
Повний текст джерелаАнотація:
Background: Although the benefits of hearing aids are generally recognized for soft- and conversational-level sounds, most studies have reported negative benefits (i.e., poorer aided than unaided performance) at high noise inputs. Advances in digital signal processing such as compression, noise reduction, and directional microphone could improve speech perception at high input levels. This could alter our view on the efficacy of hearing aids in loud, noisy situations. Purpose: The current study compared the aided versus the unaided speech intelligibility performance of hearing-impaired (HI) listeners at various input levels (from 50–100 dB SPL) and signal-to-noise ratios (SNRs; quiet, +6, +3, and –3 dB) in order to document the benefits of modern hearing aids. In addition, subjective preference between aided and unaided sounds (speech and music) at various input levels was also compared. Research Design: The experiment used a factorial repeated-measures design. Study Sample: A total of 10 HI adults with symmetrical moderate to severe hearing losses served as test participants. In addition, speech intelligibility scores of five normal-hearing (NH) listeners were also measured for comparison. Intervention: Speech perception was studied at 50 and 65 dB SPL input levels in quiet and also in noise at levels of 65, 85, and 100 dB SPL with SNRs of +6, +3, and –3 dB. This was done for all participants (HI and NH). In addition, the HI participants compared subjective preference between the aided and unaided presentations of speech and music stimuli at 50, 65, 85, and 100 dB SPL in quiet. Data Collection and Analysis: The data were analyzed with repeated-measures analysis of variance. Results: The results showed a decrease in aided benefits as input levels increased. However, even at the two highest input levels (i.e., 85 and 100 dB SPL), aided speech scores were still higher than the unaided speech scores. Furthermore, NH listeners and HI listeners in the aided condition showed stable speech-in-noise performance between 65 and 100 dB SPL input levels, except that the absolute performance of the NH listeners was higher than that of the HI listeners. Subjective preference for the unaided sounds versus the aided sounds increased as input level increased, with a crossover intensity at approximately 75 dB SPL for speech and 80 dB SPL for music. Conclusions: The results supported the hypothesis that the study hearing aid can provide aided speech-in-noise benefit at very high noise inputs in a controlled environment.
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Roozen, Irene, and Michel Meulders. "Has TV advertising lost its effectiveness to other touch points?" Communications 40, no. 4 (January 1, 2015). http://dx.doi.org/10.1515/commun-2015-0019.
Повний текст джерелаАнотація:
AbstractIn this paper we analyze the relative effectiveness of the moment of contact (touch point) between a brand and an individual consumer. The concept of effectiveness is made operational through the use of both attitude (cognitive, emotional and conative) and awareness measures (recall and recognition). The main research uses a 4x4 Latin square confounded within subjects factorial design with different touch points and brands. The appropriate stimuli were identified in a preliminary study. The results indicate that, overall, TV advertising and print advertisements – the traditional media channels – are significantly more effective than the internet, a non-traditional media channel.
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Steiner, Peter M., Christiane Atzmüller, and Dan Su. "Designing Valid and Reliable Vignette Experiments for Survey Research: A Case Study on the Fair Gender Income Gap." Journal of Methods and Measurement in the Social Sciences 7, no. 2 (June 24, 2017). http://dx.doi.org/10.2458/jmm.v7i2.20321.
Повний текст джерелаАнотація:
In survey research, vignette experiments typically employ short, systematically varied descriptions of situations or persons (called vignettes) to elicit the beliefs, attitudes, or behaviors of respondents with respect to the presented scenarios. Using a case study on the fair gender income gap in Austria, we discuss how different design elements can be used to increase a vignette experiment’s validity and reliability. With respect to the experimental design, the design elements considered include a confounded factorial design, a between-subjects factor, anchoring vignettes, and blocking by respondent strata and interviewers. The design elements for the sampling and survey design consist of stratification, covariate measurements, and the systematic assignment of vignette sets to respondents and interviewers. Moreover, the vignettes’ construct validity is empirically validated with respect to the real gender income gap in Austria. We demonstrate how a broad range of design elements can successfully increase a vignette study’s validity and reliability.
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Steiner, Peter M., Christiane Atzmüller, and Dan Su. "Designing Valid and Reliable Vignette Experiments for Survey Research: A Case Study on the Fair Gender Income Gap." Journal of Methods and Measurement in the Social Sciences 7, no. 2 (June 24, 2017). http://dx.doi.org/10.2458/v7i2.20321.
Повний текст джерелаАнотація:
In survey research, vignette experiments typically employ short, systematically varied descriptions of situations or persons (called vignettes) to elicit the beliefs, attitudes, or behaviors of respondents with respect to the presented scenarios. Using a case study on the fair gender income gap in Austria, we discuss how different design elements can be used to increase a vignette experiment’s validity and reliability. With respect to the experimental design, the design elements considered include a confounded factorial design, a between-subjects factor, anchoring vignettes, and blocking by respondent strata and interviewers. The design elements for the sampling and survey design consist of stratification, covariate measurements, and the systematic assignment of vignette sets to respondents and interviewers. Moreover, the vignettes’ construct validity is empirically validated with respect to the real gender income gap in Austria. We demonstrate how a broad range of design elements can successfully increase a vignette study’s validity and reliability.
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Shamsuddin, Md, and Mian A. S. Adnan. "THE ROW-COLUMN CONFOUNDED 2mX4n FACTORIAL DESIGN AND ITS DIFFERENT FRACTIONS." Conference on Applied Statistics in Agriculture, April 24, 2005. http://dx.doi.org/10.4148/2475-7772.1146.
Повний текст джерела
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Goyal, Vaishali, Arun Kumar Asati, Rajeev Kumar Garg, and Amit Arora. "Experimental studies on natural bank type heating/cooling energy saving Air conditioning system." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering, May 2, 2022, 095440892210960. http://dx.doi.org/10.1177/09544089221096052.
Повний текст джерелаАнотація:
The present study reports air-based novel energy saving compact bank type earth air heat exchanger system (EAHE) (having only 25m2 area) fabricated from Polyvinylchloride pipes of nominal diameter 0.203 mm (8 inches) for inlet and outlet headers and main pipes and 0.150 mm (6 inches nominal diameter) for branched pipes, which is installed in Shaheed Bhagat Singh State University, Ferozepur in Punjab state, India (North West border area of India) and studied for the duration from April to August 2021 using the full factorial design with four inlet variables at multilevel to find a model equation between inlet and outlet variables, i.e., heat exchanger effectiveness and achieved temperature difference. An induced airflow mode has been used to provide near-uniform flow through all corresponding pipes of symmetrical-shaped earth air heat exchangers. The values of Dry bulb temperature (DBT) and wet bulb temperature (WBT) have been measured for air inlet, for air outlet, as well as for ambient air using resistance temperature detectors (RTD) installed at the requisite locations. Earth's undisturbed temperature (EUT) was also noted by installing RTD at a depth of 2 m, and the average measured value of EUT is found to be 28.5°C. The current system has imparted the temperature difference variation from 0.4 oC to 9.4 oC, and the effectiveness varied from 0.16 to 0.82 during the whole season. This system could give a cooling potential of 0.0523 kJ/s to 1.587 kJ/s using a mass flow rate of 0.163 kg/s.Experiments have been designed methodically to apply the full factorial technique. Most favorable parameters have been found for hot and dry and hot and humid weather. The current study is novel in terms of significantly improving the effectiveness of EAHE and addressing the central issue of space limitation in urban areas.
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Saeed, Mohazzam, Carolina Vivian De Souza, Vitalis Chipakwe, and Saeed Chehreh Chelgani. "Influence of hydrodynamic variables on scaling up of mechanical flotation cells." Arabian Journal of Geosciences 15, no. 20 (October 2022). http://dx.doi.org/10.1007/s12517-022-10908-7.
Повний текст джерелаАнотація:
AbstractFlotation performance is influenced by many hydrodynamic variables, such as impeller speed, airflow rate, and cell geometry. These variables’ effects and interactions remain unsatisfactorily explored, especially concerning scaling-up procedures. As an innovative approach, this study considered factorial-designed experiments to explore the effects of hydrodynamic factors (impeller tip speed and superficial gas velocity) on scaling up the Outotec GTK LabCell™ mechanical flotation machine cells, common equipment used as a benchmark for many industrial pre-feasibility studies. Therefore, the influence of hydrodynamic variables and their interactions on flotation performance was evaluated in two cells (2 L and 7.5 L). The evaluation was based on the flotation rate constant “k” calculated by first- and second-order equations. Analysis of the particle size distribution indicated that the performance of the two cells was different, as shown by the finer concentrate for the 2-L cell compared to the 7.5-L cell. The outcomes demonstrated that symmetrical design in the geometry of mechanical flotation cells would lead to an accurate scaling up based on the metallurgical responses. Otherwise, the scaling procedure could only be accurate under some specific conditions. As a criterion, the results showed that using k, the scaling-up process between these two GTK LabCell™ mechanical flotation machine cells (2 L and 7.5 L) would be possible only under a specific superficial gas velocity (0.14 cm/s) apart from the impeller tip speed (R2 = 1). These results could potentially be key for the future design and development of mechanical flotation cells.
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Spanton, Rory Wilfrid, and Christopher James Berry. "EXPRESS: Does variability in recognition memory scale with mean memory strength or encoding variability in the UVSD model?" Quarterly Journal of Experimental Psychology, October 22, 2022, 174702182211364. http://dx.doi.org/10.1177/17470218221136498.
Повний текст джерелаАнотація:
The unequal variance signal detection (UVSD) model of recognition memory assumes that the variance of old item memory strength (σ<sub>o</sub>) is typically greater than that of new items. It has been suggested that this <i>old item variance effect</i> can be explained by the encoding variability hypothesis. However, Spanton and Berry (2020) failed to find evidence for this account, suggesting that σ<sub>o</sub> may simply scale with mean memory strength (<i>d</i>) in the UVSD model. Experiments 1 and 2 examined the effects of encoding variability and strength scaling on old item variance by creating conditions in which mean memory strength and variability in item characteristics was either low or high in 2 × 2 factorial designs. In Experiment 1, overall strength determined estimates of σ<sub>o</sub>, with no effect of item characteristic variability. The same effect of overall strength was found in Experiment 2; there was also a significant effect of item characteristic variability, although this manipulation also had some effect on <i>d</i> and was therefore partially confounded. Experiment 3 similarly found a simultaneous increase in old item variance and memory strength in a design using mixed item characteristic variability conditions in a single study/test block. We conclude that old item variance increases with mean memory strength in the UVSD model, with uncertainty about the effects of encoding variability, and that future explanations of the old item variance effect should bear this in mind.
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Pittaluga, Alejandro M., Chris Clark, and Alejandro E. Relling. "Effect of protein source and nonroughage NDF content in finishing diets of feedlot cattle fed free-choice hay on growth performance and carcass characteristics." Translational Animal Science 5, no. 4 (October 1, 2021). http://dx.doi.org/10.1093/tas/txab224.
Повний текст джерелаАнотація:
Abstract One-hundred twenty crossbreed steers (initial body weight (BW) 566 ± 42 kg) were used to evaluate the interaction of protein source (PS) and nonroughage NDF content (NRFC) in finishing diets of feedlot cattle fed free-choice hay on performance and carcass characteristics. Steers were stratified by BW and randomly assigned to 8 pens (2 × 2 factorial) and fed for 104 ± 10 d. Four dietary treatments were investigated: (1) distillers’ dry grains with solubles (DDGS) and a low NRFC (DLF), (2) DDGS and a high NRFC (DHF), (3) soybean meal (SBM) and a low NRFC (SLF), (4) SBM and a high NRFC (SHF). Free-choice grass hay and concentrates were offered in a different bunk. Data were analyzed as a randomized complete block design. Do to the confounded effect of PS and protein intake, a linear regression was used to evaluate the effect of protein intake in growth performance. For gain to feed ratio (G:F) an interaction tended to occur (P = 0.10) between PS and NRFC. Steers on the DHF treatment had a lower G:F compared with SLF and SHF. Feeding SBM increased (P = 0.05) final BW, tended to increase (P = 0.06) average daily gain (ADG), and decreased (P = 0.05) hay intake (HI) compared with steers fed DDGS. There was a positive association (P ˂ 0.01) of crude protein intake with ADG and FBW. Dietary NRFC did not change (P ≥ 0.3) final BW, ADG, DMI, and HI. Protein source did not affect (P ≥ 0.16) hot carcass weight (HCW), longissimus muscle (LM) area, dressing, 12th rib fat thickness, or marbling score (MS). No differences were detected between NRFC for dressing, HCW, LM area, or MS (P ≥ 0.18); but diets with greater NRFC decreased (P = 0.03) the 12th rib fat thickness. Steers in the SHF treatment presented the lesser kidney-pelvic-heart fat compared with the remaining treatments (PS × NRFC interaction, P = 0.04). Soybean meal inclusion/increase in protein intake improved growth performance of feedlot steers compared with DDGS, despite protein intake meet the protein requirement. Increasing the NRFC did not affect growth or HI but decreased feed efficiency of steers fed DDGS.