183,815 results
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152. Standards and Criteria. Paper #10 in Occasional Paper Series.
- Author
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Western Michigan Univ., Kalamazoo. School of Education. and Glass, Gene V.
- Abstract
The logical and psychological bases for setting cutting scores for criterion-referenced tests are examined; they are found to be intrinsically arbitrary and are often examples of misdirected precision and axiomatization. The term, criterion referenced, originally referred to a technique for making test scores meaningful by controlling the test development process. It has since been applied to a variety of mathematical techniques for setting cutting scores. However, because of the nature of tests and the nature of education, no process of quantification will alter the critical concern, the definition of mastery or of minimal competence, which remains either unanswered or vaguely approximate. Different methods of setting cutting scores may provide widely divergent solutions to a given problem. It is important to recognize that cutting scores are arbitrary. However, no criticism is implied with respect to criterion reference or domain reference as techniques of test construction. (CTM)
- Published
- 1977
153. Young Children's Representation of Addition and Subtraction Problems. Theoretical Paper No. 74. Conceptual Paper No. 4.
- Author
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Wisconsin Univ., Madison. Research and Development Center for Individualized Schooling. and Moser, James M.
- Abstract
A discussion is presented concerning variables associated with children's representation of certain addition and subtraction problems. Problem components are classified as physical, pictorial, sensual, verbal-spoken, verbal-written, symbolic, or internal. Problems are discussed as abstract (symbolic) or nonsymbolic. Three problem components are identified and discussed: (1) measurable entities, (2) contextual relationships or actions on entities, and (3) characteristics of the missing number. The second component is further broken down into joining, separating, equalizing, part-part-whole, and comparison. Problem structure is also discussed. (MK)
- Published
- 1979
154. A Multiple Group Measurement Model of Children's Reports of Parental Socioeconomic Status. Discussion Papers No. 531-78.
- Author
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Wisconsin Univ., Madison. Inst. for Research on Poverty., Mare, Robert D., and Mason, William M.
- Abstract
An important class of applications of measurement error or constrained factor analytic models consists of comparing models for several populations. In such cases, it is appropriate to make explicit statistical tests of model similarity across groups and to constrain some parameters of the models to be equal across groups using a priori substantive information. This paper discusses a statistical model developed by K. G. Joreskog for these purposes. The model is applied to children's and parents' reports of parental socioeconomic statuses for several grade levels. The analysis, which includes data from sons' reports of the schooling and occupations of their mothers and fathers, suggests that children do not approach their parents' level of reporting accuracy at the same rate for all characteristics; however, by twelfth grade, sons and parents are equally reliable for all characteristics considered. (Author/GC)
- Published
- 1978
155. Bibliography of Papers on Latent Trait Assessment.
- Author
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Educational Testing Service, Evanston, IL. and Cohen, Allan S.
- Abstract
This partially annotated bibliography of journal articles, dissertations, convention papers, research reports, and a few books and unpublished manuscripts provides a comprehensive coverage of work on latent trait theory and practice. Documents are arranged alphabetically by author. The period covered ranges from the early 1950's to the present. The bibliography was prepared to assist state and local education agencies make appropriate use of latent trait models in the evaluation of their Title I programs. (Author/CTM)
- Published
- 1979
156. A Process for Testing a Mathematical Model for the Solution of a Practical Problem: Application to Test Equating. LES Paper on Learning and Teaching. Paper #79.
- Author
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Douglass, James B.
- Abstract
A general process for testing the feasibility of applying alternative mathematical or statistical models to the solution of a practical problem is presented and flowcharted. The system is used to develop a plan to compare models for test equating. The five alternative models to be considered for equating are: (1) anchor test equating using classical test theory; (2) anchor test equating using the one-parameter logistic model; (3) anchor test equating using the three-parameter logistic model; (4) preequating using the one-parameter logistic model; and (5) preequating using the three-parameter logistic model. Sources of estimation instability are identified for the logistic models. Various practical and theoretical problems associated with the general process and test equating are discussed. The equating problem is of interest in its own right and serves to explicate the general process. (Author/RL)
- Published
- 1979
157. Comparative Efficiencies in Projecting Faculty Rank Distribution. AIR Forum 1980 Paper.
- Author
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Greenhill, Craig J.
- Abstract
Comparative applications of simple and complex faculty flow models are examined to determine (1) their relative demands for data and calculations, (2) the divergence of their projections, especially when modelling a no-growth faculty, and (3) an estimate of the error incurred (i.e., the cost to analysis) when a simple model is used. The results support the view that academic personnel policy changes have delayed effects and are nonlinear. It is suggested that simple models may mislead analysts by being insensitive, for example, to backlogs of term appointees who expect promotion. Similarly, it may be that no model is needed at all if one is only looking for estimates on a two-year horizon. (Author/SW)
- Published
- 1980
158. Social Background and School Continuation Decisions. Discussion Papers No. 462.
- Author
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Wisconsin Univ., Madison. Inst. for Research on Poverty. and Mare, Robert D.
- Abstract
In this paper, logistic response models of the effects of parental socioeconomic characteristics and family structure on the probability of making selected school transitions for white American males are estimated by maximum likelihood. Transition levels examined include: (l) completion of elementary school; (2) attendance at high school; (3) graduation from high school; (4) college attendance; (5) college graduation; and (6) graduate level education. It is shown that, as a consequence of the pattern of differential attrition, parental socioeconomic effects decline sharply from the earliest school transitions to the latest. Implications of differential socioeconomic background effects over schooling levels for understanding changes in level and distribution of schooling are discussed. (Author/GC)
- Published
- 1977
159. The Dynamics of Learning: A Conceptual Model. Discussion Papers #444-77.
- Author
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Wisconsin Univ., Madison. Inst. for Research on Poverty., Hallinan, Maureen, and Sorensen, Aage B.
- Abstract
In this paper, a theory of the academic achievement process of learning is proposed. Learning is seen as the outcome of the utilization of learning opportunities created in the teaching process by students themselves. These students are characterized by a certain level of ability and effort. The theory is first formulated in a single equation model for learning in which students' ability and effort is assumed constant over time. This model is then modified to take into account an interdependency between effort and achievement. Implications are derived of the proposed conceptions of the learning process for research on school effects and on inequality of educational opportunity. (Author/GC)
- Published
- 1977
160. Grambling State University's Planning/Budgeting Model: An Integral Component of a Decision Support System. SAIR Conference Paper.
- Author
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Lundy, Harold W.
- Abstract
The development of a planning/budgeting model as an integral component of a decision support system is described. The case study approach is used to describe how Grambling State University (GSU) developed the model to improve its financial planning and budgeting processes. The model can be used for tactical and/or strategic planning. The model is discussed as an example of GSU's simulation/forecasting capability. The following four basic computerized data files are used to make extrapolations: credit hours, enrollment, personnel, and fee table. With the data files and output generated from other models, the model can be used to prepare simulations and forecasts about students, faculty, staff, state appropriations, other revenues, expenditures, surpluses, and deficits. An important feature of the planning/budgeting model is that the user can change the data elements. In addition the planning/budgeting model integrates data generated by other models, i.e., the salary planning, enrollment/recruitment, and institutional cost index models. Appendices provide detailed descriptions of the various data elements that are contained in the four basic files. Also included are a list of outputs generated by the planning/budgeting model, and examples of calculations that are performed by the model. (SW)
- Published
- 1984
161. Predicting Attrition in Admissions Using a Discriminant Model. SAIR Conference Paper.
- Author
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Yost, Michael
- Abstract
A mathematical model designed to identify admitted college applicants who pay a tuition deposit but fail to attend the college was tested. A two-group discriminant model was built using 486 Trinity University students who paid deposits and enrolled as freshmen during the 1983-1984 academic year, and 72 persons who paid tuition deposits but did not enroll as freshmen. The variables included in the discriminant model were: verbal and mathematics Scholastic Aptitude Test scores, high school rank, high school grade point average, sex, amount of financial aid provided, and place of residence (in-state or out-of-state). For the 1983-1984 year, a significant difference was found between the two groups. The discriminant weights from this model were then applied to persons who paid deposits for entrance into the 1984-1985 freshman class. In this academic year, the model tested 610 students who paid deposits and enrolled and 79 persons who paid deposits but did not enroll. The second statistical analysis validated the previous year findings of a significant difference between the two groups. The accuracy of prediction was 75 percent for the 1983-1984 group and 68 percent for the 1984-1985 group. (SW)
- Published
- 1984
162. Analytical Tools for Budget Reductions: A Case Study. AIR 1984 Annual Forum Paper.
- Author
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Bloomfield, Stefan D.
- Abstract
Analytical techniques used in responding to a series of four substantial budget reductions imposed at Oregon State University are described. Over a 2-year period, each of the budget reductions demanded increasingly severe institutional action to meet the specified monetary targets. Different analytical techniques were required to meet the changing circumstances. For the first modest budget cut in June 1980, the analytical tool employed was the log-linear plot, line graphs of the student credit hour (SCH) trends for each of the university's schools and colleges. A logarithmic scale was used to identify academic units that would receive differential budget cuts. After severe budget cuts during 18 months, a computerized budget reduction model was developed that was designed to differentiate among various major categories of expense within overall budgets. Two sets of weighting factors were used for this mathematical model. Finally, in cases where program reduction or elimination was indicated, an effort was made to act equitably among affected units. The analytical tool used to define such equity was the Induced Work Load Matrix, which shows the way in which students majoring in one discipline generate SCH (and thus workload and resource requirements) in other departments. Illustrations of the use of these techniques are included. (SW)
- Published
- 1984
163. A Note on Combining Marks from Several Examination Papers.
- Author
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Charlton, P.
- Abstract
An iterative procedure for adjusting examination marks from papers of varying standards is given. The convergence of the procedure is demonstrated and attention is drawn to an underlying linear model. (MP)
- Published
- 1979
164. Analysis of Transformer Oil-Paper Insulation State Using Fractional Poynting–Thomson Model.
- Author
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Zhang, Tao, Li, Linduo, Wang, Yao, Zhang, Ning, Jiang, Shijie, and Abu-Siada, A.
- Subjects
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TRANSFORMER insulation , *POWER transformers , *PARAMETER identification , *FRACTIONAL calculus , *DIELECTRICS - Abstract
This article is aimed at quantifying the health condition of the power transformer insulation system through its frequency-domain dielectric characteristic by using the concept of the resistor and fractional calculus. In this regard, the dielectric model of the fractional Poynting–Thomson (PT) is proposed, and a mathematical model for parameter identification of the proposed model is presented. The shuffled frog leaping algorithm (SFLA) is used to realize the parameter identification and the fractional PT model parameters of the oil-paper samples under different insulation health conditions. The influence of moisture and aging on the fractional PT dielectric model parameters is experimentally studied. Results show that, with the increase in the water content within the insulation system, the parameters of the fractional PT model gradually decrease, and there is a strong correlation between the relaxation time and the water content. This facilitates the employment of the fractional PT model parameters to quantify the aging and moisture content of the power transformer insulation system. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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165. Wastewater treatment in the pulp-and-paper industry: A review of treatment processes and the associated greenhouse gas emission.
- Author
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Ashrafi, Omid, Yerushalmi, Laleh, and Haghighat, Fariborz
- Subjects
- *
WASTEWATER treatment , *PAPER industry , *GREENHOUSE gas mitigation , *MATHEMATICAL models , *ENVIRONMENTAL impact analysis , *BIOLOGICAL nutrient removal - Abstract
Pulp-and-paper mills produce various types of contaminants and a significant amount of wastewater depending on the type of processes used in the plant. Since the generated wastewaters can be potentially polluting and very dangerous, they should be treated in wastewater treatment plants before being released to the environment. This paper reviews different wastewater treatment processes used in the pulp-and-paper industry and compares them with respect to their contaminant removal efficiencies and the extent of greenhouse gas (GHG) emission. It also evaluates the impact of operating parameters on the performance of different treatment processes. Two mathematical models were used to estimate GHG emission in common biological treatment processes used in the pulp-and-paper industry. Nutrient removal processes and sludge treatment are discussed and their associated GHG emissions are calculated. Although both aerobic and anaerobic biological processes are appropriate for wastewater treatment, their combination known as hybrid processes showed a better contaminant removal capacity at higher efficiencies under optimized operating conditions with reduced GHG emission and energy costs. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
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166. Deconstructing the auxetic behavior of paper.
- Author
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Verma, Prateek, Shofner, Meisha L., and Griffin, Anselm C.
- Subjects
AUXETIC materials ,MATHEMATICAL models ,CELLULOSE fibers ,NEW product development ,PAPER ,MATERIALS science - Abstract
The objective of this research is to understand more fully the out-of-plane auxetic behavior of paper. In the reported research, initial characterization of the auxetic properties of common, commercially available papers is described. The results of these experiments suggest that the auxetic response seen in paper structures is related to the cellulose fiber network structure, as previously suggested, and is related to inter-fiber bonding and fiber organization in the sheet. These results also indicate that further study is needed to understand how materials and processing variables influence auxetic behavior. A mathematical model, attempting to explain auxetic response in an idealized arrangement of fibers is included. Ultimately, the fundamental understanding resulting from this research should lead to new product development opportunities for forest product-based paper materials as well as to the establishment of predictive structure-property relations for auxetic materials using paper as a model system. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
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167. Crushed Paper Ball and Interactive Chalkboard Murals: Their Therapeutic Use for Adult Psychiatric Inpatients (Boule de papier écrasée et murales interactives au tableau noir : leur utilisation thérapeutique pour les patients adultes hospitalisés en psychiatrie)
- Author
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Andrews, George and Kaiser, Donna
- Subjects
MENTAL illness treatment ,ART ,COUNSELING ,ACADEMIC medical centers ,CONVALESCENCE ,MATHEMATICAL models ,SYSTEMS theory ,HUMAN services programs ,CONCEPTUAL structures ,ECOSYSTEMS ,PATIENTS' attitudes ,EXPERIENCE ,ART therapy ,PLAY ,THEORY ,CASE studies ,MEDICAL practice ,DIFFUSION of innovations ,THERAPEUTIC alliance ,ADULTS - Abstract
Copyright of Canadian Journal of Art Therapy is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2023
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168. The Use of Computation Diagrams and Nomographs in Higher Education. AIR 1983 Annual Forum Paper.
- Author
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Brandenburg, Richard K. and Simpson, William A.
- Abstract
The way that graphs can be used to make calculations that are commonly used by institutional researchers is described using specific examples, and the technique of constructing computational graphs (and nomographs) is outlined. It is shown that once a calculation involving several variables has been represented by a computation diagram or a nomograph, the user can often obtain solutions more quickly than is possible by computer. Two situations in higher education that warrant the use of diagrams and nomographs are as follows: whenever a routine calculation must be performed repeatedly, using different input values; and where a relatively simple analytical model is needed to calculate responses to "what if" questions posed in the form of values assigned to input variables. It is claimed that these devices equal the performance of a microcomputer, are more convenient to undertake, and can be used by all participants in a planning session. A mathematical model relating departmental workloads, student numbers, and faculty strength is developed. Diagrams include the following: a three-variable graph and a four-variable computational diagram for analyzing a technical/professional program. Seven reference texts on nomography and two on computation diagrams are identified. (SW)
- Published
- 1983
169. Equating Logistic Ability Scales by a Weighted Least Squares Method. Iowa Testing Programs Occasional Papers, Number 27.
- Author
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Haebara, Tomokazu
- Abstract
This study develops a weighted least squares method for transforming a logistic scale in such a way that the estimates of ability parameters on the tranformed scale are as comparable as possible with those on another scale. This scale tranformation process is referred to as equating of scales. Equating is an important procedure in studies involving the logistic model and the latent trait model in general; the equating method presented deals with situations in which there are two separately scaled tests that have only some items in common (vertical equating or horizontal equating) or all items in common (horizontal equating). The necessity for equating in the later case arises when two scales have been derived by using two different groups of examinees which may have different characteristics pertinent to the results of scaling. In the former case (only some items common), the groups of examinees may or may not be overlapped. As one of the optimum estimation procedures, a weighted least squares method is introduced and applied to an achievement scale and an intelligence test. An advantage of the method over previously proposed methods is that highly discriminating items tend to affect equating more strongly than less discriminating items. (Author/RL)
- Published
- 1980
170. A Criterion-Referenced Measurement Model with Corrections for Guessing and Carelessness. Occasional Paper No. 13.
- Author
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Australian Council for Educational Research, Hawthorn. and Morgan, George
- Abstract
This study developed a two-parameter linear probabilistic model of criterion referenced measurement, which relates an examinee's observed ability to his true ability through a guessing parameter and a carelessness parameter, both of which are probabilities. This model was applied to a survey of 10- and 14-year-old Australian students to estimate the proportion who had been able to master basic skills in mathematics and literacy. The estimates were derived by using a Bayesian inferential procedure incorporating the developed measurement model within a beta-binomial, decision-theoretic framework based on a two-state conception of mastery and non-mastery. The results of a computer simulation of the model indicate that guessing and carelessness may markedly affect the determination of passing scores, and hence the accuracy of decision about mastery. The computer program for calculating cutting scores, posterior probabilities, and prior and posterior distribution statistics is appended. (Author/CTM)
- Published
- 1979
171. The Use of Mathematical Models of Student Flow in Educational Planning: A Review and Critique. DASP Planning Paper No. 3.
- Author
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North Carolina State Univ., Raleigh. Dynamic Analysis and Strategic Planning Program. and Wasik, J. L.
- Abstract
Designed for educational planners and decision makers, this report describes the application of mathematical procedures to depict the relationship of elements within models which represent the flow of students through an educational system. The introductory section includes a discussion of the history of the use of planning models in education and the steps in model development (variable identification, identification of variable interconnections, and operationalization and verification of the model). The next section reviews classification schemes for mathematical models of educational processes and presents a classification scheme developed for this report. Following this, examples of several classes of mathematical models of student flow are presented: extrapolation models; regression methods (simple first-order, polynomial, and multiple linear regression); and simultaneous equation models (non-optimizing models including the Markov Chain and optimizing models). Finally, the present utility of available mathematical models is discussed from the viewpoint of what effects these models have had on actual educational policy decision making. (Two related documents are also available in ERIC: Demography and Educational Planning [CE 019 499] and State and Local Responsibilities for Planning Occupational Education [ED 133 479].) (JH)
- Published
- 1975
172. Least Squares Method for Equating Logistic Ability Scales: A General Approach and Evaluation. Iowa Testing Programs Occasional Papers, Number 30.
- Author
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Iowa Univ., Iowa City. and Haebara, Tomokazu
- Abstract
When several ability scales in item response models are separately derived from different test forms administered to different samples of examinees, these scales must be equated to a common scale because their units and origins are arbitrarily determined and generally different from scale to scale. A general method for equating logistic ability scales was developed that uses a least squares method with weights reflecting the relative importance of correct equating at the various values on the ability continuum. The method is characterized by explicit definition of the equating error on the probability scale, minimization of the overall error, and coherence of the equating in all directions. It is applicable when the test forms are linked by common items, and various linkage patterns can be used. When there are more than m - 1 links among m test forms, a restricted solution is provided to insure an internally consistent system of equatings. Results of the application of the method to many computer-generated data sets indicated that the accuracy of the obtained estimates of the equating constants was generally satisfactory and that the number of common items in the linked pairs of test forms was the most important factor in determining the accuracy of estimation. (Author/GK)
- Published
- 1981
173. The Standard Errors of the Feldt-Gilmer Congeneric Reliability Coefficients: Iowa Testing Programs Occasional Papers. Number 31.
- Author
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Iowa Testing Programs, Iowa City., Gilmer, Jerry S., and Feldt, Leonard S.
- Abstract
The Feldt-Gilmer congeneric reliability coefficients make it possible to estimate the reliability of a test composed of parts of unequal, unknown length. The approximate standard errors of the Feldt-Gilmer coefficients are derived via a method using the multivariate Taylor's expansion. Monte Carlo simulation is employed to corroborate the theoretical approximations for eight hypothetical tests. The Feldt-Gilmer coefficients are shown to be appropriate with both congeneric and tau-equivalent parts. Their superiority over the special case of Kristof's coefficient increases with the number of parts. Their standard errors also compare favorably to that of Cronbach's alpha coefficient when applied to tests with tau-equivalent parts. Tables illustrate the charts. (Author/CM)
- Published
- 1982
174. Unidimensional Measurement and Confirmatory Factor Analysis. Occasional Paper No. 20.
- Author
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Michigan State Univ., East Lansing. Inst. for Research on Teaching., Hunter, John E., and Gerbing, David W.
- Abstract
Confirmatory factor analysis is presented as providing appropriate techniques for the analysis and evaluation of questionnaires and tests if the content of the measure can be identified as consisting of groups of items, with each group measuring only a single trait. This approach is contrasted with latent trait theory which assumes (and does not test) the assumption of unidimensionality. The first step in the analysis is the partitioning of the items into distinct scales or clusters, preferably on the basis of an a priori analysis of item content, although blind exploratory statistical methods may be substituted. The parameters of the model are estimated by oblique multiple groups factor analysis and include the correlations between items and factors, the correlations between the factors, and the communality of each item. This analysis will confirm, or disconfirm, the measurement model specified by the user. Chi square tests are provided for unidimensionality of clusters and parallelism. Appendices contain proofs and computer programs. (Author/CTM)
- Published
- 1979
175. Before the Roof Caves in: A Predictive Model for Physical Plant Renewal--Part II. APPA Technical Paper.
- Author
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Association of Physical Plant Administrators of Universities and Colleges, Washington, DC., Hutson, Robert E., and Biedenweg, Frederick M.
- Abstract
Examples of the use of a mathematical model to evaluate the future renewal and replacement, or maintenance requirements, of the college physical plant are provided. The model, which was developed at Stanford University, simulates actual conditions at a specific location and allows resource allocation to be based on a definable quantitative base. The approach is based on a concept of cyclical renewal and replacement. The age cohort or birthdate of the facility and subsystems were derived by using 5-year increments beginning with initial construction in 1891. Tables provide information on: the construction date of each facility (by type) along with the square footage of that facility; the life cycles and resulting costs of a building built in 1950 containing 10,000 square feet; the sum of the tables for each individual building and the total expected cost in millions (1980 dollars) for each of the categories listed by cohort; and four possible versions of the total annual cost of interior finishes and special equipment, and other subsystems (i.e., likely cost, optimistic cost, pessimistic cost, and smoothed cost). It is concluded that this model will serve as the basis for a program by which renewal needs are identified in a creditable manner. (SW)
- Published
- 1982
176. Before the Roof Caves in: A Predictive Model for Physical Plant Renewal. APPA Technical Paper.
- Author
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Association of Physical Plant Administrators of Universities and Colleges, Washington, DC., Hutson, Robert E., and Biedenweg, Frederick M.
- Abstract
A quantitative method developed at Stanford University that addresses programmatically the short- and long-term needs of the college physical plant is discussed. The approach allows the administrator to accurately assess funding resources for the maintenance program in conjunction with academic and construction programs. A special task force at the university established a conceptual framework based on predictable cycles for facility renewal and replacement. The task force identified five features that would affect the wearing out of the facility and system and the resulting replacement/renewal costs. These five features were: facility subsystems, facility type, subsystem life cycles, subsystem cost, and date of facility construction. These features were quantified by analyzing the existing physical plant and by researching available data. The objective was to forecast future renewal and replacment requirements. Using data that reflected actual conditions at the university, it was possible to model accurately Stanford's physical plant and to simulate the future renewal/replacement requirements. Each of the five features and resulting data set are discussed in detail in order to outline the methodology used for developing the data. (SW)
- Published
- 1982
177. Modelling for Schools/Colleges. South Bank Research Series in Mathematical/Computing Education 1. An External Paper.
- Author
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Polytechnic of the South Bank, London (England). Dept. of Mathematical Sciences and Computing., Kapadia, Ramesh, and Kyffin, Huw
- Abstract
This document consists of seven chapters. The first chapter analyzes the modeling process and gives reasons for introducing a modeling approach in classrooms, arguing that students will develop more confident and positive attitudes toward mathematics. The next five chapters contain case studies, which focus, respectively on: whether it is more economical to rent or buy a television set; how pricing policy affects profit; how a rear window wiper should be positioned on an automobile to sweep the maximum area; the mathematics of the long jump; and which of three schools should be shut due to declining enrollments (by calculating traveling time by different modes of transportation). Each of these chapters includes: an introduction to the problem to be modeled, with prerequisites and the target age-range (and learning objectives, when applicable); list of assumptions on which the model is based; an influence diagram showing the relationship between factors; model development (which may consist of several parts); and a concluding section which draws out implications and gives ideas for further work. Assessment items are included for several models. The final chapter contains a list of models which could be used in the classroom together with a list of references and a bibliography. (JN)
- Published
- 1985
178. Trading Away Jobs: The Effects of the US Merchandise Trade Deficit on Employment. Working Paper No. 102.
- Author
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Economic Policy Inst., Washington, DC., Duchin, Faye, and Lange, Glenn-Marie
- Abstract
A study was conducted to describe the segments of the U.S. labor force that have been affected by the recent deterioration in U.S. trade. The methodology involved computer modeling of the effects of eliminating the 1987 merchandise trade deficit on employment by detailed industry and occupation, by geographic region, and by wage group. This was done by calculating the number of jobs of different characteristics and in different industries that are required for the production of merchandise exports and those that would be required for the domestic production of imports. All computations were made with an input-output model of the U.S. economy using the most recent trade data (1987), providing a consistent framework for simultaneously computing the detailed production requirements of every industry. The advantage of this approach was that it allowed the calculation of all production requirements for satisfying a given bill of final deliveries, in this case, imports and exports. Specific findings were as follows: (1) the record trade deficit in 1987 represented a loss of 5.1 million job opportunities, 2 million of which were lost between 1984 and 1987; (2) 60 percent, or 3.1 million of the total 5.1 million jobs lost, were in manufacturing, and the remaining 2 million jobs were lost in industries closely related to manufacturing, primarily in business services; (3) each of the four regions lost over 1 million jobs because of the trade deficit, with the Midwest and the West each losing 1.4 million jobs; and (4) the wages of the jobs from trade were more likely to be high-wage jobs. The most important conclusions were that the employment effects of the trade deficit are large and more dispersed in the economy than commonly believed. (A 14-item reference list and two appendices, one on U.S. Merchandise Trade in 1987 and one on methodology and classifications, are attached.) (NLL)
- Published
- 1988
179. Fluidization and incineration of pulp and paper mill sludge in BFB
- Author
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Wang, W
- Published
- 1999
180. Artistic Innovation of Famous Paper-cutting Artist Wang Xiaying.
- Author
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MA Lianjing and WANG Yichuan
- Subjects
- *
PAPER arts , *TECHNOLOGICAL innovations , *SUSTAINABLE development , *CHINESE art , *MATHEMATICAL models - Abstract
Paper-cutting is a traditional Chinese art, and Fuyang paper-cutting is a miracle of Chinese paper-cutting art. As Fuyang paper-cutting art is gradually promoted by artists during the historical inheritance, its traditional form has changed, a batch of new-style paper-cutting artworks have been created, Wang Xiaying is a leading figure in its inheritance. From the perspective of manifestation means and modeling language, this paper found that Wang Xiaying on the basis of inheriting traditional paper-cutting learned from other arts, applied innovative techniques to break through limitations in modeling, and realized the innovation of paper-cutting art It was concluded that traditional paper-cutting arts could only achieve sustainable development by integrating with new elements. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
181. New trends in the state research methodology of complex systems of paper and paperboard production
- Subjects
методологія ,математичні моделі ,адекватність моделей ,моделювання ,виробництво паперу та картону ,органічні водорозчинні речовини ,methodology ,mathematical models ,model adequacy ,modeling ,paper and cardboard production ,organic water-soluble substances - Abstract
For the analyst, experiment is the most important stage in many fundamental and applied research. In order to study the object as much as possible and learn about the complex of its properties, it is necessary to investigate it, namely: to carry out experimental researches and to record the results of these studies on the media. This is necessary to compare the achieved level of knowledge of the object with that of the researcher in the process of literary and patent searches. In the future, the knowledge gained during the experimental research is used for practical purposes. This is the main task of scientific search. In turn, the effectiveness of experimental research largely depends on the methodology used in the process of scientific research.The researcher's attention should be focused on at least three aspects of carrying out the search work, at the expense of which it is possible to save considerable time and material resources and, at the same time, to obtain the desired results.In the first stage, it should be noted that the study of the state of technological systems for the production of semi-finished products, paper and cardboard shows that the individual blocks of such technological systems, and therefore the whole technological system is affected by the mass of independent deterministic values, called factors. These factors exert their influence in the process of mass preparation, including the stage of dissolution; cleaning; grinding; composing the composition; casting; pressing, drying of a cloth. After all, the production of paper or cardboard is a sequence of interrelated processes, which, in the long run, ultimately depend on the quality of the products being manufactured.In order to effectively reduce the number of factors that exert their influence, it is advisable for the experimenter to make a preliminary assessment of the influence of each of the factors identified in the literature and patent searches, and to form a group of the most significant factors on this basis. In the future, these factors will be involved in the next stages of experimental research. However, intuitive selection of significant factors is quite subjective and may lead to erroneous conclusions from the results of the analysis of the research results. Therefore, at the stage of preliminary research it is recommended to use statistical methods of selection of factors, namely: methods of expert assessments. These methods are based on the statistical processing of data obtained from a survey of specialists in the field of knowledge or analysis of scientific research. Expert assessments are based on the results of the most recent and unpublished scientific works performed by each expert.Despite their subjectivity, peer reviews provide useful, objective information. This information makes it possible to evaluate the impact of each factor under study. Using this method, the opinion of the expert group is considered to be more reliable than the opinion of the individual expert. The method is based on the fact that the unknown characteristic of the studied phenomenon is treated as a random variable, and each expert's individual assessment of the truth and significance of an event is a reflection of its law of distribution.In the second stage of research, an important aspect is to achieve maximum informativeness of the experiment. It is known that in the course of experimental research, the object under study responds differently to changing factors (one or more simultaneously) and, thus, exhibits its complex of properties. The task of the researcher is to plan the experimental studies so that the object in the course of its research maximally manifested its entire complex of properties, regardless of the internal structure of the investigated object, as well as the influence of these or other factors. Thus, the maximum reliability of the results of experimental studies in the conditions of random "noise" interference is ensured. Subsequently, multicriteria analysis of the basic plans and local transformations of each of them are carried out in order to select the most suitable for implementation at the request of the researcher. This is the second aspect of the methodology.The third, and very important, aspect of research methodology is the development of adequate mathematical models [4], on the basis of which a favorable field is created for modeling and finding optimal conditions with the use of computer technologies. At this stage, taking into account the complexity of technological systems for the production of semi-finished products, paper and cardboard, a number of adequate mathematical models, suitable for modeling purposes, have been created.Further stages of research work are the use of created mathematical models for modeling purposes. The task is to predict the levels of pollution of water flows of complex technological systems of paper and cardboard production with water-soluble organic, as well as mineral components under conditions of reduction of fresh water consumption from 40 m3 \ t to 10 m3\ t. This will give you an opportunity to determine the initial semi-finished products, a complex of auxiliary chemicals, as well as with the scheme of return water use., Розроблено методологію, яка дозволяє передбачити значення параметрів оптимізації у станах (точках факторного простору), що не досліджувалися в процесі проведення експерименту. Моделювання відбувається на базі комплексу адекватних математичних моделей, які створені на основі попередньо проведених експериментальних досліджень. Моделюванню піддаються процеси екстракції водорозчинних органічних речовин із волокнистих напівфабрикатів в процесах виробництва паперу та картону з мінімальним споживанням свіжої води.
- Published
- 2020
182. A Novel Methanol-Based DP Estimation Method With a New Methanol Peak Detector Index for Aging Assessment of Power Transformer Insulation Paper.
- Author
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Teymouri, Ashkan, Vahidi, Behrooz, and van der Wielen, Peter
- Subjects
- *
TRANSFORMER insulation , *POWER transformers , *DEGREE of polymerization , *DETECTORS , *METHANOL as fuel , *METHANOL - Abstract
Methanol concentration as an aging indicator can assess cellulose aging and estimate cellulose degree of polymerization (DP). Despite the advantages of methanol (MeOH), its major disadvantage is that its concentration in the oil decreases after some time. This point is called the MeOH peak in this article. Therefore, using this indicator when MeOH concentration is reduced leads to incorrect results. When using methanol, the main problem is that whenever the methanol concentration in a transformer is measured, it cannot be identified that the measured concentration belongs to the left or right side of the MeOH peak. If the measured concentration belongs to the right side of the MeOH peak, the estimated DP is incorrect. In this article, an empirical equation is established to estimate the DP value as a function of methanol concentration when methanol concentration belongs to the left side of the MeOH peak. Then, a new index called methanol peak detector index (MPDI) composed of a 2-furfural/MeOH ratio and normalized DP is presented to ensure the validity of the calculated DP value. If it is found that the measured concentration belongs to the left side of the MeOH peak, then the estimated DP by the presented equation is valid. Finally, the application of this method is verified by applying it to measurement data samples indicating the validity of the method. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
183. A BPNN Model-Based AdaBoost Algorithm for Estimating Inside Moisture of Oil–Paper Insulation of Power Transformer.
- Author
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Liu, Jiefeng, Ding, Zheshi, Fan, Xianhao, Geng, Chuhan, Song, Boshu, Wang, Qingyin, and Zhang, Yiyi
- Subjects
- *
POWER transformers , *TRANSFORMER insulation , *MOISTURE , *ALGORITHMS , *MACHINE learning , *CLASSIFICATION algorithms - Abstract
The traditional method for transformer moisture diagnosis is to establish empirical equations between feature parameters extracted from frequency domain spectroscopy (FDS) and the transformer’s moisture content. However, the established empirical equation may not be applicable to a novel testing environment, resulting in an unreliable evaluation result. In this regard, it is acknowledged that FDS combined with machine learning is more suitable for estimating moisture content in a variety of test environments. Nonetheless, the accuracy of the estimation results obtained using the existing method is limited by the algorithm’s inability to generalize. To address this issue, we propose an AdaBoost algorithm-enhanced back-propagation neural network (BP_AdaBoost). This study creates a database by extracting feature parameters from the FDS that characterize the insulation states of the prepared samples. Then, using the BP_AdaBoost algorithm and the newly constructed database, the moisture estimation models are trained. Finally, the results of the estimation are discussed in terms of laboratory and field transformers. By comparing the proposed BP_AdaBoost algorithm to other intelligence algorithms, it is demonstrated that it not only performs better in generalization, but also maintains a high level of accuracy. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
184. Resisting Marginalization with Culturally Responsive Mathematical Modeling in Elementary Classrooms
- Author
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Erin Turner, Julia Aguirre, Mary Alice Carlson, Jennifer Suh, and Elizabeth Fulton
- Abstract
Mathematical modeling (MM) -- a cyclical process that involves using mathematics to make-sense of and analyze relevant, real-world situations -- has the potential to advance equity and challenge spaces of marginalization in the elementary mathematics classroom. When informed by culturally responsive teaching practices, MM creates opportunities to center the knowledge and experiences that students from diverse racial, cultural, and linguistic backgrounds bring to the classroom as valuable resources to support learning and inform action. It can disrupt power and status hierarchies in the classroom that contribute to structural and ideological marginalization. This paper describes ways teachers connected their teaching of MM with key components of a culturally responsive mathematics teaching framework. Analysis synthesizes data from an innovative, research-based professional development for elementary teachers to support teacher learning of equity-centered, culturally responsive MM instruction. Data sources include end of year teacher interviews, and professional development discussions from 19 teachers at four geographically, racially, and culturally diverse sites. Findings focus on how teachers connected their teaching of MM with key dimensions of culturally responsive mathematics teaching, and affordances and challenges related to resisting ideological and structural forms of marginalization.
- Published
- 2024
- Full Text
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185. Enhancing Recall in Automated Record Screening: A Resampling Algorithm
- Author
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Zhipeng Hou and Elizabeth Tipton
- Abstract
Literature screening is the process of identifying all relevant records from a pool of candidate paper records in systematic review, meta-analysis, and other research synthesis tasks. This process is time consuming, expensive, and prone to human error. Screening prioritization methods attempt to help reviewers identify most relevant records while only screening a proportion of candidate records with high priority. In previous studies, screening prioritization is often referred to as automatic literature screening or automatic literature identification. Numerous screening prioritization methods have been proposed in recent years. However, there is a lack of screening prioritization methods with reliable performance. Our objective is to develop a screening prioritization algorithm with reliable performance for practical use, for example, an algorithm that guarantees an 80% chance of identifying at least 80% of the relevant records. Based on a target-based method proposed in Cormack and Grossman, we propose a screening prioritization algorithm using sampling with replacement. The algorithm is a wrapper algorithm that can work with any current screening prioritization algorithm to guarantee the performance. We prove, with mathematics and probability theory, that the algorithm guarantees the performance. We also run numeric experiments to test the performance of our algorithm when applied in practice. The numeric experiment results show this algorithm achieve reliable performance under different circumstances. The proposed screening prioritization algorithm can be reliably used in real world research synthesis tasks.
- Published
- 2024
- Full Text
- View/download PDF
186. An integrated approach to the optimisation of water usage and discharge in pulp and paper plants.
- Author
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Lovelady, Eva M., El-Halwagi, Mahmoud, and Krishnagopalan, Gopal A.
- Subjects
PAPER industry ,WOOD pulp industry ,WATER quality management ,MATHEMATICAL models ,MATHEMATICAL statistics ,COST effectiveness ,PULPING ,MANUFACTURING processes ,SEWAGE disposal - Abstract
This paper is aimed at developing a systematic methodology for the cost-effective reduction of water usage and discharge in pulp and paper plants. As the industry moves towards increased system closure, the build-up of Non-Process Elements (NPEs) leads to serious consequences on the process equipment. In response, this paper achieves the following: • a mathematical model to track water and primary NPEs throughout the pulping process • rigorous targeting for water usage and discharge • a systematic framework for water reduction using mass integration strategies including no/low cost techniques as well as capital-based techniques • an optimisation model for the optimisation of allocation, recycle and separation of aqueous streams. A case study for water management in a kraft pulping process has been solved to highlight the usefulness of the devsied approach. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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187. Statistical Foundations for Model Validation: Two Papers
- Author
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EASTERLING, ROBERT
- Published
- 2003
- Full Text
- View/download PDF
188. Modelling End-of-Session Actions in Educational Systems
- Author
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Hansen, Christian, Hansen, Casper, Alstrup, Stephen, and Lioma, Christina
- Abstract
In this paper we consider the problem of modelling when students end their session in an online mathematics educational system. Being able to model this accurately will help us optimize the way content is presented and consumed. This is done by modelling the probability of an action being the last in a session, which we denote as the End-of-Session probability. We use log data from a system where students can learn mathematics through various kinds of learning materials, as well as multiple types of exercises, such that a student session can consist of many different activities. We model the End-of-Session probability by a deep recurrent neural network in order to utilize the long term temporal aspect, which we experimentally show is central for this task. Using a large scale dataset of more than 70 million student actions, we obtain an AUC of 0.81 on an unseen collection of students. Through a detailed error analysis, we observe that our model is robust across different session structures and across varying session lengths. [For the full proceedings, see ED599096.]
- Published
- 2019
189. Open Professional Development of Math Teachers through an Online Course
- Author
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Brancaccio, Anna, Esposito, Massimo, Marchisio, Marina, Sacchet, Matteo, and Pardini, Claudio
- Abstract
The professional development of teachers is a task recognized by the European parliament and pursued by many institutions, both national and international ones. The support to teachers in STEM disciplines was one of the aims of the Erasmus+ SMART (Science and Mathematics Advanced Research for good Teaching) project, born in a European context, which developed as its main intellectual output two open online courses called Mathematical Modelling and Observing, Measuring and Modelling in Science, in order to help teachers in their continuous professional development. Both courses contain interactive problem-based materials ready to be downloaded, modified, used in the classroom and redistributed to the community. This paper gives an overview of the structure of the course Mathematical Modelling and analyzes its instructional quality, taking into account some measurables obtained in two years of operativity. [For the full proceedings, see ED621557.]
- Published
- 2019
190. Mathematical approach towards non-stepwise performance assessment in HUASB reactor for wastewater treatment from pulp and paper mills.
- Author
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Hemalatha, D., Narayanan, R. M., and Kanna, G. Vinoth
- Subjects
WASTEWATER treatment ,PAPER mills ,BIOREACTORS ,RF values (Chromatography) ,MATHEMATICAL models - Abstract
A lab-scale Hybrid Upflow Anaerobic Sludge Blanket (HUASB) reactor with a working volume of 6.5 litres has been taken for the performance analysis, in the treatability study of pulp and paper mill wastewater. In order to analyze the performance of the reactor, operational parameter like hydraulic retention time (HRT) was varied from 10, 20, 30 and 40 h. In addition to that, performance parameters like chemical oxygen demand (COD), pH, volatile fatty acids (VFA), alkalinity, gas production and VFA/alkalinity ratio are analyzed to check the reactor efficacy. The maximum COD removal efficiency of 81.3% is obtained at 40 h HRT, with gas production (methane content of 58%). Also, the obtained results are fitted to the kinetic models like the standard first order, first order and second order to evaluate the performance of the HUASB reactor. [ABSTRACT FROM AUTHOR]
- Published
- 2021
191. Approaches to Integration Based on Quantitative Reasoning: Adding Up Pieces and Accumulation from Rate
- Author
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Jones, Steven R. and Ely, Robert
- Abstract
Calculus education research on integration is coalescing around the theme that teaching integration based on quantitative reasoning is crucial for robust understanding of and usage of integrals. This paper contributes to this International Journal for Research in Undergraduate Education special issue on the teaching and learning of definite integrals by reviewing the research literature on quantitatively-based approaches to integration, in order to pull together the ideas that are spread across many papers in many outlets. We note that the literature in this area has largely developed along two distinct paradigms, which we call "adding up pieces and accumulation from rate." While they are both based in quantitative reasoning, there are critical differences between them that have important ramifications for teaching and learning integration. We use these two paradigms to organize our review and we use the literature to discuss the meanings, formalizations, foci, reasoning, and modeling in these approaches.
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- 2023
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192. Characterizing carbonaceous biochemical oxygen demand load reductions from pulp and paper mills for activities related to total maximum daily loads.
- Author
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Palumbo, James E. and Brown, Linfield C.
- Subjects
WASTE management ,BIOCHEMICAL oxygen demand ,COMPUTER simulation ,MATHEMATICAL models ,PAPER ,PULP mills - Abstract
The article presents a conceptual framework using simulation to predict effluent biochemical oxygen demand (BOD) characteristics as a function of improved wastewater treatment. These simulations use equations that describe BOD kinetics. They also able to reproduce trends in f-ratio observed at various pulp and paper facilities and predict BOD reactivity as a function of treatment.
- Published
- 2010
193. Paper, Plaster, Strings: Exploratory Material Mathematical Models between the 1860s and 1930s.
- Author
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Friedman, Michael
- Subjects
- *
PLASTER , *MATHEMATICAL models , *THREE-dimensional modeling , *NINETEENTH century , *CASE studies - Abstract
Does the materiality of a three-dimensional model have an effect on how this model operates in an exploratory way, how it prompts discovery of new mathematical results? Material mathematical models were produced and used during the second half of the nineteenth century, visualizing mathematical objects, such as curves and surfaces—and these were produced from a variety of materials: paper, cardboard, plaster, strings, wood. However, the question, whether their materiality influenced the status of these models—considered as exploratory, technical, or representational—was hardly touched upon. This article aims to approach this question by investigating two case studies: Beltrami's paper models vs. Dyck's plaster ones of the hyperbolic plane; and Chisini's string models of braids vs. Artin's and Moishezon's algebraization of these braids. These two case studies indicate that materiality might have a decisive role in how the model was taken into account mathematically: either as an exploratory or rather as a technical or pedagogical object. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
194. An Analysis of Young's Modulus Distribution in the Paper Plane.
- Author
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Szewczyk, Włodzimierz, Marynowski, Krzysztof, and Tarnawski, Wiktorian
- Subjects
TEXTILE research ,PAPER ,MATHEMATICAL models ,TESTING ,ELASTICITY ,MATHEMATICAL physics - Abstract
Within our research work we determined the Young's modulus distribution in the paper plane on the basis of results of tensile tests in selected directions. Using mathematical relationships valid for orthotropic materials, the moduli were calculated theoretically. The tensile stiffness orientation angle (TSA), and the TSO and TSI indices were also determined in order to define the deviations of the main axes of orthotrophy in the paper plane as determined by the machine and the cross directions. The calculation results were compared with measured values. They justified the conclusion that paper may be treated as an orthotropic material. [ABSTRACT FROM AUTHOR]
- Published
- 2006
195. Adult Pulmonary Intensive and Intermediate Care Units: The Italian Thoracic Society (ITS-AIPO) Position Paper.
- Author
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Renda, Teresa, Scala, Raffaele, Corrado, Antonio, Ambrosino, Nicolino, and Vaghi, Adriano
- Subjects
- *
HOSPITAL respiratory services , *PULMONOLOGISTS , *RESPIRATORY insufficiency , *PROFESSIONS , *HEALTH services administration , *RESPIRATORY therapy equipment , *MATHEMATICAL models , *REGULATORY approval , *SUBACUTE care , *MEDICAL care use , *RESPIRATORY therapy , *CRITICAL care medicine , *HOSPITAL wards , *QUALITY assurance , *THEORY , *ADULTS - Abstract
The imbalance between the prevalence of patients with acute respiratory failure (ARF) and acute-on-chronic respiratory failure and the number of intensive care unit (ICU) beds requires new solutions. The increasing use of non-invasive respiratory tools to support patients at earlier stages of ARF and the increased expertise of non-ICU clinicians in other types of supportive care have led to the development of adult pulmonary intensive care units (PICUs) and pulmonary intermediate care units (PIMCUs). As in other European countries, Italian PICUs and PIMCUs provide an intermediate level of care as the setting designed for managing ARF patients without severe non-pulmonary dysfunction. The PICUs and PIMCUs may also act as step-down units for weaning patients from prolonged mechanical ventilation and for discharging patients still requiring ventilatory support at home. These units may play an important role in the on-going coronavirus disease 2019 pandemic. This position paper promoted by the Italian Thoracic Society (ITS-AIPO) describes the models, facilities, staff, equipment, and operating methods of PICUs and PIMCUs. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
196. Temporal Frequency of Flickering-Distortion Optimized Video Halftoning for Electronic Paper.
- Author
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Hsu, Chao-Yung, Lu, Chun-Shien, and Pei, Soo-Chang
- Subjects
- *
ELECTRONIC paper , *ELECTRIC distortion , *PIXELS , *SENSITIVITY analysis , *PROBABILITY theory , *MATHEMATICAL models , *VIDEOS , *LIGHTING - Abstract
Video halftoning is a key technology for use in electronic paper (e-paper) or smart paper, which is an emerging display device that has received considerable attention recently. In this paper, a temporal frequency of flickering-distortion optimized video halftoning method is proposed. We first uncover three visual defects that conventional neighboring frame referencing-based video halftoning methods, due to their sequential changes of reference frames, will encounter. To deal with the problem, we then propose a reference frame update per GOP-based error diffusion video halftoning method based on a flickering sensitivity-based human visual model. To efficiently compromise between average temporal frequency of flickering (ATFoF) and visual quality, temporal frequency of flickering-distortion (TFoFD) is presented as a metric for video halftoning performance evaluation. Based on the proposed probability model of video halftoning, the TFoFD curve can be accurately estimated to optimize the tradeoff between quality and ATFoF before the video is halftoned. Our temporal frequency of flickering-distortion optimization strategy can also be applied to other video halftoning schemes for performance improvement. Experimental results and comparisons with known methods demonstrate the effectiveness of our video halftoning method. [ABSTRACT FROM PUBLISHER]
- Published
- 2011
- Full Text
- View/download PDF
197. Kernel Smoothing Item Response Theory in R: A Didactic
- Author
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Effatpanah, Farshad and Baghaei, Purya
- Abstract
Item response theory (IRT) refers to a family of mathematical models which describe the relationship between latent continuous variables (attributes or characteristics) and their manifestations (dichotomous/polytomous observed outcomes or responses) with regard to a set of item characteristics. Researchers typically use parametric IRT (PIRT) models to measure educational and psychological latent variables. However, PIRT models are based on a set of strong assumptions that often are not satisfied. For this reason, non-parametric IRT (NIRT) models can be more desirable. An exploratory NIRT approach is kernel smoothing IRT (KS-IRT; Ramsay, 1991) which estimates option characteristic curves by non-parametric kernel smoothing technique. This approach only gives graphical representations of item characteristics in a measure and provides preliminary feedback about the performance of items and measures. Although KS-IRT is not a new approach, its application is far from widespread, and it has limited applications in psychological and educational testing. The purpose of the present paper is to give a reader-friendly introduction to the KS-IRT, and then use the KernSmoothIRT package (Mazza et al., 2014, 2022) in R to straightforwardly demonstrate the application of the approach using data of Children's Test Anxiety scale.
- Published
- 2023
198. Discussion of Paper by D.V. Lindley
- Author
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Dinges, H.
- Published
- 1982
- Full Text
- View/download PDF
199. Using Log Data to Validate Performance Assessments of Mathematical Modeling Practices
- Author
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Olsen, Joe, Adair, Amy, Gobert, Janice, Sao Pedro, Michael, and O'Brien, Mariel
- Abstract
Many national science frameworks (e.g., Next Generation Science Standards) argue that developing mathematical modeling competencies is critical for students' deep understanding of science. However, science teachers may be unprepared to assess these competencies. We are addressing this need by developing virtual lab performance assessments that assess these competencies in science inquiry contexts. Through our design processes, we developed a method for validating the assessments that takes advantage of the unique opportunities afforded by collecting log data. Here, we describe this method and demonstrate its utility by analyzing students' competencies with one example sub-practice of mathematical modeling, "plotting controlled data generated from a simulation." [This is a paper in: M. M. Rodrigo et al. (Eds.): AIED 2022, LNCS 13356, (pp. 488--491), 2022.]
- Published
- 2022
- Full Text
- View/download PDF
200. Flexible Stock Allocation and Trim Loss Control for Cutting Problem in the Industrial-Use Paper Production.
- Author
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Fu-Kwun Wang and Feng-Tai Liu
- Subjects
- *
CUTTING stock problem , *PAPER products industry , *MATHEMATICAL models , *PRODUCTION (Economic theory) , *PROBLEM solving - Abstract
We consider a one-dimensional cutting stock problem (CSP) in which the stock widths are not used to fulfill the order but kept for use in the future for the industrial-use paper production. We present a new model based on the flexible stock allocation and trim loss control to determine the production quantity. We evaluate our approach using a real data and show that we are able to solve industrial-size problems, while also addressing common cutting considerations such as aggregation of orders, multiple stock widths, and cutting different patterns on the same machine. In addition, we compare our model with others, including trim loss minimization problem (TLMP) and cutting stock problem (CSP). The results show that the proposedmodel outperforms the other two models regarding total flexibility and trim loss ratio. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
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