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Uniform designs have been widely used in physical and computer experiments due to their robust performances. The level permutation method can efficiently construct uniform designs with both lower discrepancy and less aberration. However, the related existing literature has mostly discussed uniform fixed-level designs, the construction of uniform mixed-level designs has been quite few studied. In this paper, a novel level permutation method for constructing uniform mixed-level designs is proposed. Our main idea is to perform level permutations on a new class of designs, called minimum average discrepancy designs, rather than generalized minimum aberration designs as in the fixed-level case. Several theoretical results on the design optimality and construction are obtained. Numerical results suggest the good performance of the resulting designs under various popular discrepancies.

This paper describes the response surface model for mixed-level factors of the form 2n×3 where experimental units/plots experience the overlap effects from immediate left and right neighboring unit...

This study implemented differentiated instruction (DI) featuring tiered tasks and heterogeneous grouping tasks in three mixed-level English classes at a military institution in Taiwan, a setting th...

Purpose Low pilling and wrinkle-free appearance of cellulosic fabrics are always demanded. Resin finishes are applied to improve these properties, but there is an adverse effect of the resin finish as it tends to reduce the strength of the fabrics. Therefore, the effect of the two most important finishes; anti-pilling and resin finish, on the strength characteristics of 100% viscose and 50:50 Viscose/cotton plain and satin fabrics were investigated in this paper. The purpose of this study is to identify significant factors affecting the strength of fabrics finished with crosslinking agents [non-ionic acrylate copolymer and (dimethyloldihydroxyethyleneurea)]. Design/methodology/approach A statistical model of 23 32 mixed level factorial design was used for the study. Appratan N9211 (A) and Arkofix NF (B) were tested at three concentrations, whereas three factors fabric; weave (C), blend ratio (D) and curing method (E) were tested at two levels. The performance of the finish was evaluated by two response variables, which were tensile and tear strength. Findings The various conditions of high strength values of the fabrics were presented in this paper. It was found that the tear strength of the fabrics increased after finishing except for 50:50 viscose/cotton plain fabric, whereas the tensile strength of plain fabrics is better at shock cure and for a satin normal cure is better. The model adequacy plots exhibit that the assumptions of normality and independence are not desecrated. Moreover, the values of “predicted R2” are in reasonable agreement with the “adjusted R2,” which confirms that models have been accounted for most of the inconsistency. Originality/value This paper is a part of my PhD dissertation. Unlike the previous studies, this paper investigated the effect of two crosslinking agents, Appretan N9211 as anti-pilling and Arkofix NF as wrinkle resistant agents on 100% viscose and 50:50 viscose/cotton plain and satin. Three different concentrations of both the crosslinking agents were used. Also, fixation of the finishes was carried out at a normal cure and shock cure.

Pilling resistance characteristics of rayon and rayon/cotton fabrics was improved by combining anti-piling and resin finish using a statistical technique. A 2332-mixed level factorial design was chosen. Five factors were selected: anti-pilling agent and resin finish (at three levels), and fabric blend ratio, fabric weave, and curing method (at two levels). Two response variables—pilling before and after wash—were analyzed at the sixth level using contour and interaction plots. A high pilling grade (4.5) was achieved on plain rayon and rayon/cotton fabrics using one concentration range of anti-pilling agent and resin finish (normal or shock cure), and for satin fabric using a different concentration range of anti-pilling agent and resin finish. Normal curing gave good pilling grades compared to those using shock curing.

This paper considers the construction of mixed-level supersaturated split-plot designs (SSSPDs) which are very useful in screening situations where the number of factors is larger than the number of available observations and several of these factors have levels that they are hard to change. As a benchmark of obtaining optimal SSSPDs, lower bounds to our proposed designs are established. Illustrative examples are presented supporting our constructed designs.

Evidence-based librarianship (EBL) has been in the literature for around 20 years, and has received a mixed level of acceptance and adoption in its implementation. The purpose of this study is to identify the determinants of EBL adoption and implementation in library acquisition decision of electronic resources. The Technology-Organization-Environment (TOE) model, Innovation Diffusion Theory (IDT) theory and EBL model were used to form the research framework in order to investigate the adoption and implementation of evidence-based acquisition (EBA). Questionnaires were used as data collection tool. Data were collected from 250 respondents comprising librarians from academic, public and special libraries. The data were analyzed descriptively using Statistical Product and Service Solutions (SPSS) v24. The assessment of the measurement and structural model was executed using Smart-PLS (SEM) 3.0. The reflective model was found to be valid and reliable with the Cronbach’s Alpha above 0.70, CR value and AVE of 0.80-0.90. Fornell-Larcker Criterion and Item Cross-loading recordings revealed that the constructs did not discriminate each other. Path coefficient analysis was performed to test the hypothesis in the identification of significant relationship that resulted in Relative Advantage, Compatibility and Top Management Support as the determinants of EBA of electronic resources Although no significant relationship was found between EBL Adoption and Implementation, an indication of practice was recorded in the level of implementation analysis. Further action and future research for libraries were suggested.

Covering arrays and locating arrays have been investigated in depth in various scenarios. Test suites based on locating arrays can not only test the presence of system defects, but also identify ef...

Alias structures for two-level fractional designs are commonly used to describe the correlations between different terms. The concept of alias structures can be extended to other types of designs such as fractional mixed-level designs. This paper proposes an algorithm that uses the Pearson’s correlation coefficient and the correlation matrix to construct alias structures for these designs, which can help experimenters to more easily visualize which terms are correlated (or confounded) in the mixed-level fraction and constitute the basis for efficient sequential experimentation.

The fractional factorial split-plot (FFSP) design is an important experimental design both in theory and in practice. There is extensive literature on the two-level FFSP design and its various variants. However, there is little work on the s-level FFSP design and its variants in the asymmetrical (i.e., mixed-level) case, where s is any prime or prime power. Such designs are commonly used e.g. in agriculture, medicine and chemistry. This paper provides the necessary and sufficient conditions for the existence of resolution III or IV regular $$s^{(n_1+n_2)-(k_1+k_2)}(s^r)$$ designs which contain clear main effects or two-factor interaction components. In particular, the sufficient conditions are proved through constructing the corresponding designs, and some examples are provided to illustrate the construction methods.

The uniformity criterion under Lee discrepancy favors designs with the smallest Lee discrepancy value. Based on quaternary codes, the present paper explores the construction of four-level and mixed two- and four-level fractional factorial designs with zero Lee discrepancy. A general construction method is provided, and our theoretic results show that designs with zero Lee discrepancy can be obtained from two-level full factorial designs. When measuring uniformity by Lee discrepancy, designs with a value of zero apparently are optimal. In particular, an additional lower bound on Lee discrepancy is not required.

This paper introduces a new class of Hadamard matrix-based mixed-level foldover designs (MLFODs) and an algorithm which facilitates the construction of MLFODs. Our new MLFODs were constructed by co...

Mixed-level designs have a wide application in the fields of medicine, science, and agriculture, being very useful for experiments where there are both, quantitative, and qualitative factors. Traditional construction methods often make use of complex programing specialized software and powerful computer equipment. This article is focused on a subgroup of these designs in which none of the factor levels are multiples of each other, which we have called pure asymmetrical arrays. For this subgroup we present two algorithms of zero computational cost: the first with capacity to build fractions of a desired size, and the second, a strategy to increase these fractions with M additional new runs determined by the experimenter, this is an advantage over the folding methods presented in the literature in which at least half of the initial runs are required. In both algorithms, the constructed fractions are comparable to those showed in the literature as the best in terms of balance and orthogonality.

Building the first Russian-Vietnamese neural machine translation system, we faced the problem of choosing a translation unit system on which source and target embeddings are based. Available homogeneous translation unit systems with the same translation unit on the source and target sides do not perfectly suit the investigated language pair. To solve the problem, in this paper, we propose a novel heterogeneous translation unit system, considering linguistic characteristics of the synthetic Russian language and the analytic Vietnamese language. Specifically, we decrease the embedding level on the source side by splitting token into subtokens and increase the embedding level on the target side by merging neighboring tokens into supertoken. The experiment results show that the proposed heterogeneous system improves over the existing best homogeneous Russian-Vietnamese translation system by 1.17 BLEU. Our approach could be applied to building translation bots for language pairs with different linguistic characteristics.

Many recently proposed methods for Neural Architecture Search (NAS) can be formulated as bilevel optimization. For efficient implementation, its solution requires approximations of second-order methods. In this paper, we demonstrate that gradient errors caused by such approximations lead to suboptimality, in the sense that the optimization procedure fails to converge to a (locally) optimal solution. To remedy this, this paper proposes \mldas, a mixed-level reformulation for NAS that can be optimized efficiently and reliably. It is shown that even when using a simple first-order method on the mixed-level formulation, \mldas\ can achieve a lower validation error for NAS problems. Consequently, architectures obtained by our method achieve consistently higher accuracies than those obtained from bilevel optimization. Moreover, \mldas\ proposes a framework beyond DARTS. It is upgraded via model size-based search and early stopping strategies to complete the search process in around 5 hours. Extensive experiments within the convolutional architecture search space validate the effectiveness of our approach., Comment: This paper is published in CVPR 2020 (IEEE/CVF Conference on Computer Vision and Pattern Recognition 2020)

This paper studies mixed-level designs with multi block variables, denoted by (2r)×2n:2l . Some necessary and sufficient conditions on the existence of clear treatment two-factor interaction compon...

Purpose The purpose of this paper is to use convolutional neural networks in order to solve the problem of the difficulty in the classification of cashmere and wool. To do the research, it proposes a low-dimensional strategy of using part-level features to enhance object-level features. The study aims to use computer version method to find out the most effective and robust method to manage the difficult task of cashmere and wool identification. Design/methodology/approach The authors try to get a coarse classification result and the initial weights of the model in the first step. The authors use the results of the first step and a Fast-RCNN method to extract part-level features in step 2. Finally, the authors mix the part-level features to enhance object-level features and classify the cashmere and wool images. Findings The paper finds that not only the texture is the key element of the cashmere and wool identification but also the image colors. Originality/value Most importantly, the paper finds that the part-level features can enhance object-level features in the fiber identification task. However, it does not work in contrast, and the strategy can be used in the similar fibers identifications.

The objective of this article is to study the issue of projection uniformity along the line of Fang and Qin (2005) and Qin, Wang and Chatterjee (2012) based on discrete discrepancy for mixe...

Collaborative learning is a promising avenue in education research. Learning from others and with others can foster deeper learning at a multiple-choice assignment, but it is hard to control the level of students' pure guessing. This paper addresses the problem of promoting collaborative learning through regulation of guessing when students use clickers to answer multiple-choice questions of various levels of difficulty. The study is aimed at identifying how the difficulty of the task and students' levels of knowledge influence on the degree of partial guessing. To answer this research question, we developed two research models and validated them by testing 84 students with regard to the students' level of knowledge and the penalty announcement. The findings of this research reveal that: a) the announcement of penalty has a negative effect on promoting collaborative learning even if it leads to reducing pure guesses in test results; b) questions that require higher-order thinking skills promote collaborative learning to a greater extent; c) creating mixed level groups of students seems advisable to enhance learning from collaboration and, thus, to decrease the degree of pure guessing.

A covering design is a traditional class of experimental plans for hardware and software testing purposes. This paper presents a class of size-optimal covering designs for testing experiments with mixed-level factors. Among all the factors of different levels, one or two factors have a high number of levels while other factors form a full factorial so that all level combinations among factor pairs are “covered” at least once and appeared almost equally frequent. We use the coloring techniques for hypergraphs to construct such near-balanced mixed-level covering designs with the minimum run size.

A new high-level implementation independent functional fault model for control faults in microprocessors is introduced. The fault model is based on the instruction set, and is specified as a set of data constraints to be satisfied by test data generation. We show that the high-level test, which satisfies these data constraints, will be sufficient to guarantee the detection of all non-redundant low level faults. The paper proposes a simple and fast simulation based method of generating test data, which satisfy the constraints prescribed by the proposed fault model, and a method of evaluating the high-level control fault coverage for the proposed fault model and for the given test. A method is presented for identification of the high-level redundant faults, and it is shown that a test, which provides 100% coverage of non-redundant high-level faults, will also guarantee 100% non-redundant SAF coverage, whereas all gate-level SAF not covered by the test are identified as redundant. Experimental results of test generation for the execution part of a microprocessor support the results presented in the paper., Comment: 2019 IEEE Latin American Test Symposium (LATS)

Land cover classification from airborne data is considered a challenging task in Remote Sensing. Even in the case of available elevation data, shadows and strong intra-class variations of appearances are abundant in urban terrain. In this paper, we propose an approach for supervised land cover classification that has three main contributions. Firstly, for the cumbersome task of training data sampling we propose an algorithm which combines the freely available OpenStreetMap data with the actual sensor data and requires only a minimum of user interaction. The key idea of this algorithm is to rasterize the vector data using a fast segmentation result. Secondly, pixel-wise classification may take long and be quite sensitive to the resolution and quality of input data. Therefore, superpixel decomposition of images, supported by a general framework on operations with superpixels, guarantees fast grouping of pixel-wise features and their assignment to one of four important classes (building, tree, grass and road). Particularly for extraction of street canyons lying in the shadowy regions, high-level features based on stripes are introduced. Finally, the output of a probabilistic learning algorithm can be postprocessed by a non-local optimization module operating on Markov Random Fields, thus allowing to correct noisy results using a smoothness prior. Extensive tests on three datasets of quite different nature have been performed with two probabilistic learners: The well-known Random Forest and by far less known Import Vector Machine are explored. Thus, this work provides insights about promising feature sets for both classifiers. The quantitative results for the ISPRS benchmark dataset Vaihingen are promising, achieving up to 94.5% and 87.1% accuracy on superpixel and on pixel level, respectively, despite the fact that only around 10% of available labeled data were used. At the same time, the results for two additional datasets, validated with the autonomously acquired training data, yielded a significantly lower number of misclassified superpixels. This confirms that the proposed algorithm on training data extraction works quite well in reducing errors of second kind. However, it tends to extract predominantly huge and easy-to-classify areas, while in complicated, ambiguous regions, first type errors often occur. For this and other algorithm shortcomings, directions of future research are outlined.

The aim of this study is to identify effective classroom management. For this study, the researcher observed each class four times and conducted oral interviews with two native English teachers and two Korean English teachers. The data gathered is from classroom observation, in-depth interview, and existing documents. According to the results of the analysis, several of the problems facing English teachers in elementary schools were moving room to room, mixed level classes, large class size, use of the mother tongue, and cultural differences. Secondly, English teachers try to manage their classrooms effectively according to their beliefs and experiences. Lastly, the research participants recommended effective classroom management. With respect to these findings, this study is expected to give English teachers in elementary school a chance to reflect on their own classroom management styles and improve them.

This paper discusses an algorithm for constructing mixed-level screening designs (MLSDs) by augmenting some columns of a definitive screening designs (DSDs) with additional two-level columns. The constructed designs have the quadratic effects being orth..

This paper considers the derivation of a new lower bound for the generalized discrete discrepancy of designs involving mixed level factors. Using mirror mapping and foldover techniques, a simple and efficient construction method of Sudoku-based mixed level uniform designs is proposed. Moreover, the properties of such Sudoku-based mixed level uniform designs are investigated.

There is an ongoing digital revolution motivated by the data-driven scientific discovery paradigm. Geophysics has a mixed level of readiness, with some of these technologies already applied, research still emerging, and new opportunities to be discovered.

This paper aims at revealing the hydraulic fracturing effect of hydrodynamic influencing factors of fracturing fluid by laboratory experiments. The experimental design for huge number of hydrodynamic influencing factors with many levels, is oftentimes incorporated with the conventional methods, i.e. Based on the PKN model, injection rate, viscosity, and density (of the fracturing fluid) and their parameter values (levels) were considered for the construction of an optimal mixed-level design table U* 12(43×6), which constructed the optimization scheme. The experiments results were subjected to multiple regression analysis to establish optimal fitting formulas for the relationship of single factor or multi-factor with rock fracturing value. Compared with other experimental designs, experimental number of U* 12(43×6) yielded only half the number of experiments in the orthogonal design L24(43×6) and presented better distribution uniformity of experimental points than Ui2(43×6). This paper provides a fast and effective experimental scheme for the effect analysis, as well as a substantially accurate method for in-situ stress measurement.

We show that a tensor product of nonexceptional type Kirillov--Reshetikhin (KR) crystals is isomorphic to a direct sum of Demazure crystals; we do this in the mixed level case and without the perfectness assumption, thus generalizing a result of Naoi. We use this result to show that, given two tensor products of such KR crystals with the same maximal weight, after removing certain $0$-arrows, the two connected components containing the minimal/maximal elements are isomorphic. Based on the latter fact, we reduce a tensor product of higher level perfect KR crystals to one of single-column KR crystals, which allows us to use the uniform models available in the literature in the latter case. We also use our results to give a combinatorial interpretation of the Q-system relations. Our results are conjectured to extend to the exceptional types., 15 pages, 1 figure; v2, incorporated changes from referee

The attention level of human beings is a very complicated property of the brain. It has demanded a lot of research work which is still being continued to understand how it works on different situations as the human brain shows a mixed level of attention. The attention level is generally derived from the alpha and beta waves processed in the human brain. With the help of an EEG device which is alternatively called as a brain–computer interface (BCI), it can retrieve the data from the human brain. The sole purpose of this study is to find out how the attention level of the human being gets affected when it turns the moods from normal to the stressed. How much variation does the two moods show in terms of attention. It can also be taken into consideration in finding out how much difference is there in the attention levels of boys and girls keeping for both the moods of the human beings. It has been studied how does the age group affect the brains’ attention level when considered a young and an older group of students. It has been collected data from 30 students each of which were girls and boys and of age groups 20 and 22 years. It has been experimented on the data collected and found that with the normal mood the human showed a better level of concentration and attention level than that of the stressed mood. It has been also noticed that the girls irrespective of their moods showed greater value of attention than the boys. The last results showed that the elder group showed a better level of attention than the younger one concluding that with the increase in age, the attention level gets increased.

Follow-up experimental designs are popularly used in industry. In many follow-up designs, some additional factors with two or three levels may be added in the follow-up stage since they are quite important but may be neglected in the first stage. Such follow-up designs are called mixed-level column augmented designs. In this paper, based on the initial designs, mixed-level column augmented uniform designs are proposed by using the uniformity criterion, wrap-around $L_2$-discrepancy (WD). The multi-stage augmented procedure which adds the additional design points stage by stage is also investigated. We present the analytical expressions and the corresponding lower bounds of the WD of the column augmented designs. It is shown that the column augmented uniform designs are also the optimal designs under the non-orthogonality criterion, $E(f_{NOD})$. Furthermore, a construction algorithm for the column augmented uniform design is provided. Some examples show that the lower bounds are tight and the construction algorithm is effective., 43 pages

Given an Orthogonal Array we analyze the aberrations of the sub-fractions which are obtained by the deletion of some of its points. We provide formulae to compute the Generalized Word-Length Pattern of any sub-fraction. In the case of the deletion of one single point, we provide a simple methodology to find which the best sub-fractions are according to the Generalized Minimum Aberration criterion. We also study the effect of the deletion of 1, 2 or 3 points on some examples. The methodology does not put any restriction on the number of levels of each factor. It follows that any mixed level Orthogonal Array can be considered., Comment: 13 pages, 5 tables

This chapter describes measures of association for two variables at different levels of measurement, e.g., a nominal-level independent variable and an ordinal- or interval-level dependent variable, and an ordinal-level independent variable and an interval-level dependent variable. This chapter begins with discussions of three measures of association for a nominal-level independent variable and an ordinal-level dependent variable: Freeman’s θ, Agresti’s \(\hat{\delta}\), and Piccarreta’s \(\hat {\tau }\). This chapter continues with a discussion of measures of association for a nominal-level independent variable and an interval-level dependent variable: the correlation ratio η2, 𝜖2, and \(\hat {\omega }^{2}\).

As the complementary metal oxide semiconductor feature size shrinks further, single event multiple transients (SEMTs) become more serious. However, SEMTs have not yet been appropriately modelled through traditional soft error rate (SER) estimation methods. Therefore, this paper presents a mixed-level framework to estimate SER induced by SEMTs. The precision of the proposed framework is verified through HSPICE simulation. The results show that multiple pulses and convergence of SEMTs significantly affect SER estimation.

The purpose of our study is to investigate works of scholars about the problems of listening and speaking in learning foreign languages. We try to analyze the difficulties in doing listening and speaking exercises in mixed level groups focusing on “New English File” (Intermediate) textbook. “New English File” presents different kinds of listening and speaking tasks in order to improve all four skills (listening, reading, speaking, and writing). In our study we refer to Wenden's statement (1986), who noted that we need to find out listening problems in order to improve listening skill. According to it, we discovered difficulties not only in listening, but also in speaking of students in mixed level groups. These difficulties helped us to find the ways of improving students’ abilities to listen to authentic materials and apply them in communication. Problems in listening and speaking in mixed level groups were taken from the results of questionnaire. Students’ questionnaire determined the effective ways of using role plays and various activities in practice. The result of our study showed that the textbook was worse using in mixed level groups. Different creative activities in English classes motivate students to learn foreign languages, and improve knowledge.

5th World Conference on Learning, Teaching and Educational Leadership, WCLTA 2014 -- OCT 29-31, 2014 -- Prague, CZECH REPUBLIC Bekiryazici, Merve/0000-0001-9685-7380 WOS: 000380499600143 One of the biggest challenges that teachers face is the mixed-level classes, where students have different abilities, backgrounds and interests. All classes can be defined as 'mixed' since no student is the same as the other and this makes it difficult for teachers to meet each student's needs. the purpose of this study is to identify this problem by using Lev Vygotsky's 'Zone of Proximal Development' (ZPD) theory as a background and suggest solutions for teachers by making use of Vygotsky's ideas such as peer tutoring and scaffolding. While the starting point of the problem is English language classes at universities in Turkey, suggestions offered for effective teaching are in a more global context. (C) 2015 the Authors. Published by Elsevier Ltd.

Mixed-level designs are widely used in factorial experiments. Clear effects criterion is one of the important rules for selecting optimal fractional factorial designs. It is highly desirable to know when mixed-level designs with resolution III or IV can have clear two-factor interaction components. This paper considers mixed-level designs with one or two high-level factors and some two-level factors, denoted as \((2^{r})\times 2^n\) and \((2^{r_1})\times (2^{r_2})\times 2^n\), respectively, and gives a complete classification of the existence of clear two-factor interaction components in such designs with resolution III or IV. The results reveal the structures of these designs.

This paper considers the study of the optimality of the extended design generated by adding few runs to an existing E ( χ 2 ) -optimal mixed-level supersaturated design. This paper covers the work of Gupta et al. (2010, 2012) on extended two-level and s -level supersaturated designs as two special cases. A lower bound to E ( χ 2 ) has been obtained for the proposed designs. A small example is presented here attaining the lower bound.

Most interactive sports-oriented products that are commercially available focus on individual athletes. The ones that focus on team sports rarely go beyond performance monitoring. Therefore, in this case study we focus on team dynamics in secondary school sports teams. These teams typically have to deal with unbalanced engagement due to skill level differences. This can impede the goals of these PE-classes; to raise young people's enthusiasm for a variety of sports and to teach them how to work together as a team. In this project we explore a design solution aimed at balancing engagement in these mixed level sports teams, through an intelligent system of connected light jerseys. The jerseys, iteratively developed through experiential prototypes that were used during secondary school basketball games, were able to measure ball possession and give feedback through a series of light stripes. In this paper we describe two iterations of this case study and our quantitative and qualitative findings of team engagement.