Chemically based mathematical model for development of cerebral cortical folding patterns.
Deborah A Striegel
2009-09-01
Full Text Available The mechanism for cortical folding pattern formation is not fully understood. Current models represent scenarios that describe pattern formation through local interactions, and one recent model is the intermediate progenitor model. The intermediate progenitor (IP model describes a local chemically driven scenario, where an increase in intermediate progenitor cells in the subventricular zone correlates to gyral formation. Here we present a mathematical model that uses features of the IP model and further captures global characteristics of cortical pattern formation. A prolate spheroidal surface is used to approximate the ventricular zone. Prolate spheroidal harmonics are applied to a Turing reaction-diffusion system, providing a chemically based framework for cortical folding. Our model reveals a direct correlation between pattern formation and the size and shape of the lateral ventricle. Additionally, placement and directionality of sulci and the relationship between domain scaling and cortical pattern elaboration are explained. The significance of this model is that it elucidates the consistency of cortical patterns among individuals within a species and addresses inter-species variability based on global characteristics and provides a critical piece to the puzzle of cortical pattern formation.
Mathematical Modeling of Chemical Stoichiometry
Croteau, Joshua; Fox, William P.; Varazo, Kristofoland
2007-01-01
In beginning chemistry classes, students are taught a variety of techniques for balancing chemical equations. The most common method is inspection. This paper addresses using a system of linear mathematical equations to solve for the stoichiometric coefficients. Many linear algebra books carry the standard balancing of chemical equations as an…
Basuki Widodo
2012-02-01
Full Text Available Corrosion process is a natural case that happened at the various metals, where the corrosion process in electrochemical can be explained by using galvanic cell. The iron corrosion process is based on the acidity degree (pH of a condensation, iron concentration and condensation temperature of electrolyte. Those are applied at electrochemistry cell. The iron corrosion process at this electrochemical cell also able to generate electrical potential and electric current during the process takes place. This paper considers how to build a mathematical model of iron corrosion, electrical potential and electric current. The mathematical model further is solved using the finite element method. This iron corrosion model is built based on the iron concentration, condensation temperature, and iteration time applied. In the electric current density model, the current based on electric current that is happened at cathode and anode pole and the iteration time applied. Whereas on the potential electric model, it is based on the beginning of electric potential and the iteration time applied. The numerical results show that the part of iron metal, that is gristle caused by corrosion, is the part of metal that has function as anode and it has some influences, such as time depth difference, iron concentration and condensation temperature on the iron corrosion process and the sum of reduced mass during corrosion process. Moreover, difference influence of time and beginning electric potential has an effect on the electric potential, which emerges during corrosion process at the electrochemical cell. Whereas, at the electrical current is also influenced by difference of depth time and condensation temperature applied.Keywords: Iron Corrosion, Concentration of iron, Electrochemical Cell and Finite Element Method
Basuki Widodo
2012-01-01
Corrosion process is a natural case that happened at the various metals, where the corrosion process in electrochemical can be explained by using galvanic cell. The iron corrosion process is based on the acidity degree (pH) of a condensation, iron concentration and condensation temperature of electrolyte. Those are applied at electrochemistry cell. The iron corrosion process at this electrochemical cell also able to generate electrical potential and electric current during the process takes p...
Mathematical modeling a chemical engineer's perspective
Rutherford, Aris
1999-01-01
Mathematical modeling is the art and craft of building a system of equations that is both sufficiently complex to do justice to physical reality and sufficiently simple to give real insight into the situation. Mathematical Modeling: A Chemical Engineer's Perspective provides an elementary introduction to the craft by one of the century's most distinguished practitioners.Though the book is written from a chemical engineering viewpoint, the principles and pitfalls are common to all mathematical modeling of physical systems. Seventeen of the author's frequently cited papers are reprinted to illus
Identification of Chemical Reactor Plant’s Mathematical Model
Pyakillya Boris
2015-01-01
Full Text Available This work presents a solution of the identification problem of chemical reactor plant’s mathematical model. The main goal is to obtain a mathematical description of a chemical reactor plant from experimental data, which based on plant’s time response measurements. This data consists sequence of measurements for water jacket temperature and information about control input signal, which is used to govern plant’s behavior.
Chemical Graph Theory--The Mathematical Connection
Gutman, Ivan
The impact that research done in chemical graph theory (CGT) had and has on "serious" or "pure" mathematics is examined. Although this impact is minor, it is not fully negligible. By means of two case studies we intend to demonstrate the following general features of the CGT --> Mathematics connection: (a) Scholars familiar with chemistry design a mathematical model of the examined chemical phenomena; (b) such a model may require the usage of non-trivial mathematical objects and methods, and may lead to difficult and interesting mathematical problems; (c) in order to grasp the significance of a particular mathematical object/method/problem of CGT, mathematicians need a very long time, sometimes as much as 20-30 years; (d) once this significance is recognized, a vigorous mathematical research begins; (e) mathematicians usually generalize and extend the original object/method/problem of CGT, and the results they obtain may be lacking value for CGT. The two case studies pertain to the graph energy and the connectivity (or Randic) index.
Basitere, Moses; Ivala, Eunice
2015-01-01
This paper reports on a study carried out at a University of Technology, South Africa, aimed at identifying the existence of the mathematical knowledge gap and evaluating the intervention designed to bridge the knowledge gap amongst students studying first year mathematics at the Chemical Engineering Extended Curriculum Program (ECP). In this…
A New Mathematical Formulation of the Governing Equations for the Chemical Compositional Simulation
Bekbauov, Bakhbergen E; Berdyshev, Abdumauvlen
2015-01-01
It is the purpose of this work to develop new approach for chemical compositional reservoir simulation, which may be regarded as a sequential method. The development process can be roughly divided into the following two stages: (1) development of a new mathematical formulation for the sequential chemical compositional reservoir simulation, (2) implementation of a sequential solution approach for chemical compositional reservoir simulation based on the formulation described in this paper. This paper addresses the first stage of the development process by presenting a new mathematical formulation of the chemical compositional reservoir flow equations for the sequential simulation. The newly developed mathematical formulation is extended from the model formulation used in existing chemical compositional simulators. During the model development process, it was discovered that the currently used chemical compositional model estimates the adsorption effect on the transport of a component reasonably well but it viol...
Mathematical Modeling of Tin-Free Chemically-Active Antifouling Paint Behavior
Yebra, Diego Meseguer; Kiil, Søren; Dam-Johansen, Kim;
2006-01-01
Mathematical modeling has been used to characterize and validate the working mechanisms of tin-free, chemically-active antifouling (AF) paints. The model-based analysis of performance data from lab-scale rotary experiments has shown significant differences between antifouling technologies as rega...... of Chemical Engineers....
Conceptualising inquiry based education in mathematics
Blomhøj, Morten; Artigue, Michéle
2013-01-01
The terms inquiry-based learning (IBL) and inquiry-based education (IBE) have appeared with increasing frequency in educational policy and curriculum documents related to mathematics and science education over the past decade, indicating a major educational trend. We go back to the origin of...... frameworks in mathematics education. Six such frameworks are analysed from the perspective of inquiry: the problem-solving tradition, the Theory of Didactical Situations, the Realistic Mathematics Education programme, the mathematical modelling perspective, the Anthropological Theory of Didactics, and the...... inquiry as a pedagogical concept in the work of Dewey (e.g. 1916, 1938) to analyse and discuss its migration to science and mathematics education. For conceptualizing inquiry-based mathematics education (IBME) it is important to analyse how this concept resonates with already well-established theoretical...
Chemical Literacy Levels of Science and Mathematics Teacher Candidates
Celik, Suat
2014-01-01
The goal of this study was to investigate Turkish science and mathematics teacher candidates' levels of attainment in chemical literacy. These candidates had all studied the new Turkish chemistry curriculum in high school. The sample of the study consisted of 112 students, who were first-year students in the Department of Secondary Science…
Ge, Hao
2016-01-01
This paper studies a mathematical formalism of nonequilibrium thermodynamics for chemical reaction models with $N$ species, $M$ reactions, and general rate law. We establish a mathematical basis for J. W. Gibbs' macroscopic chemical thermodynamics under G. N. Lewis' kinetic law of entire equilibrium (detailed balance in nonlinear chemistry kinetics). In doing so, the equilibrium thermodynamics is then naturally generalized to nonequilibrium settings without detailed balance. The kinetic models are represented by a Markovian jumping process. A generalized macroscopic chemical free energy function and its associated balance equation with nonnegative source and sink are the major discoveries. The proof is based on the large deviation principle of this type of Markov processes. A general fluctuation dissipation theorem for stochastic reaction kinetics is also proved. The mathematical theory illustrates how a novel macroscopic dynamic law can emerges from the mesoscopic kinetics in a multi-scale system.
Mesoscopic Kinetic Basis of Macroscopic Chemical Thermodynamics: A Mathematical Theory
Ge, Hao
2016-01-01
From a mathematical model that describes a complex chemical kinetic system of $N$ species and $M$ elementrary reactions in a rapidly stirred vessel of size $V$ as a Markov process, we show that a macroscopic chemical thermodynamics emerges as $V\\rightarrow\\infty$. The theory is applicable to linear and nonlinear reactions, closed systems reaching chemical equilibrium, or open, driven systems approaching to nonequilibrium steady states. A generalized mesoscopic free energy gives rise to a macroscopic chemical energy function $\\varphi^{ss}(\\vx)$ where $\\vx=(x_1,\\cdots,x_N)$ are the concentrations of the $N$ chemical species. The macroscopic chemical dynamics $\\vx(t)$ satisfies two emergent laws: (1) $(\\rd/\\rd t)\\varphi^{ss}[\\vx(t)]\\le 0$, and (2)$(\\rd/\\rd t)\\varphi^{ss}[\\vx(t)]=\\text{cmf}(\\vx)-\\sigma(\\vx)$ where entropy production rate $\\sigma\\ge 0$ represents the sink for the chemical energy, and chemical motive force $\\text{cmf}\\ge 0$ is non-zero if the system is driven under a sustained nonequilibrium chemos...
Developing Mathematics Problems Based on Pisa Level
Shahibul Ahyan
2014-01-01
Full Text Available This research aims to produce mathematics problems based on PISA level with valid and practical content of change and relationships and has potential effect for Junior High School students. A development research method developed by Akker, Gravemeijer, McKenney and Nieveen is used this research. In the first stage, the researcher analyzed students, algebra material in school-based curricula (KTSP and mathematics problems of PISA 2003 of change and relationships content. The second stage, the researcher designed 13 problems with content of change and relationships. The last, the researcher used formative evaluation design developed by Tessmer which includes self evaluation, one-to-one, expert review, small group, and field test. The data collect by walk through, interview, and questionnaire. The result of this research indicated that 12 mathematical problems based on PISA level of change and relationships content that developed have validity, practically, and potential effects for Junior High School students.
A mathematical model of symmetry based on mathematical definition
刘玉生; 杨将新; 吴昭同; 高曙明
2002-01-01
Tolerance is imperative for seamless integration of CAD/CAM(Computer Aided Disignd/Computer Aided Manufacture) which is just a text attribute and has no semantics in present CAD systems. There are many tolerance types, the relations between which are very complicated. In addition, the different principles of tolerance make study of tolerance difficult; and there may be various meanings or interpretation for the same type of tolerance beeanse of the literal definition. In this work, latest unambiguous mathematical definition was applied to study, explain and clarify: ( 1 ) the formation and representation of tolerance zone, and (2) the formation and representation of variational elements ; after which, the mathematical models of syrmmetry of different tolerance principles and different interpretations were derived. An example is given to illustrate the application of these models in tolerance analysis.
Mathematical programming solver based on local search
Gardi, Frédéric; Darlay, Julien; Estellon, Bertrand; Megel, Romain
2014-01-01
This book covers local search for combinatorial optimization and its extension to mixed-variable optimization. Although not yet understood from the theoretical point of view, local search is the paradigm of choice for tackling large-scale real-life optimization problems. Today's end-users demand interactivity with decision support systems. For optimization software, this means obtaining good-quality solutions quickly. Fast iterative improvement methods, like local search, are suited to satisfying such needs. Here the authors show local search in a new light, in particular presenting a new kind of mathematical programming solver, namely LocalSolver, based on neighborhood search. First, an iconoclast methodology is presented to design and engineer local search algorithms. The authors' concern about industrializing local search approaches is of particular interest for practitioners. This methodology is applied to solve two industrial problems with high economic stakes. Software based on local search induces ex...
From (Deductive) Fuzzy Logic to (Logic-Based) Fuzzy Mathematics
Cintula, Petr
Berlin: Springer, 2009 - (Sossai, C.; Chemello, G.) ISBN 978-3-642-02905-9. ISSN 0302-9743. [ECSQARU 2009. European Conference /10./. 01.07.2009-03.07. 2009, Verona] Institutional research plan: CEZ:AV0Z10300504 Keywords : fuzzy class theory * non-classical mathematics * logic-based fuzzy mathematics Subject RIV: BA - General Mathematics
Place-Based Mathematics Education: A Conflated Pedagogy?
Showalter, Daniel A.
2013-01-01
Place-based mathematics education (PBME) has the potential to engage students with the mathematics inherent in the local land, culture, and community. However, research has identified daunting barriers to this pedagogy, especially in abstract mathematics courses such as algebra and beyond. In this study, 15 graduates of a doctoral program in rural…
Biza, Irene; Nardi, Elena; Joel, Gareth
2015-01-01
In this paper we present the results from a study conducted in a UK institution in which 21mathematics pre-service teachers engage with two practice-based tasks featuring incidents where classroom management interferes with mathematical learning. We investigate their considerations when they make decisions in classroom situations and how these tasks can trigger their reflections on the teaching and learning of mathematics. In our analysis we used the constructs of social and sociomathematical...
Mathematical Expression Recognition based on Probabilistic Grammars
Álvaro Muñoz, Francisco
2015-01-01
[EN] Mathematical notation is well-known and used all over the world. Humankind has evolved from simple methods representing countings to current well-defined math notation able to account for complex problems. Furthermore, mathematical expressions constitute a universal language in scientific fields, and many information resources containing mathematics have been created during the last decades. However, in order to efficiently access all that information, scientific doc...
Paterson, Judy; Sneddon, Jamie
2011-01-01
This article reports on the learning conversations between a mathematician and a mathematics educator as they worked together to change the delivery model of a third year discrete mathematics course from a traditional lecture mode to team-based learning (TBL). This change prompted the mathematician to create team tasks which increasingly focused…
Ge, Hao; Qian, Hong
2016-01-01
This paper studies a mathematical formalism of nonequilibrium thermodynamics for chemical reaction models with $N$ species, $M$ reactions, and general rate law. We establish a mathematical basis for J. W. Gibbs' macroscopic chemical thermodynamics under G. N. Lewis' kinetic law of entire equilibrium (detailed balance in nonlinear chemistry kinetics). In doing so, the equilibrium thermodynamics is then naturally generalized to nonequilibrium settings without detailed balance. The kinetic model...
Teacher practice in an inquiry-based Mathematics classroom
Menezes, Luís; Oliveira, Hélia; Canavarro, Ana Paula
2012-01-01
This paper presents a framework for an inquiry-based approach to mathematics teaching. It was developed by combining theoretical perspectives and case studies of experienced teacher that usually conduct inquiry based teaching of mathematics. This framework describes the actions teachers intentionally perform with two identified purposes: to promote the mathematical learning of the students and to manage the students and the class as a whole.
A Study of Mathematics Web-Based Learning in Schools
Mansoor A.A Ali
2008-01-01
Full Text Available Teaching Mathematics to intermediate school boys is a challenging process which can greatly benefit from software technology and web-based learning. In this research we study the difficulties and opportunities of using this technology in teaching Mathematics to 13 year old boys studying Mathematics at school. For students' we identify the basic requirements at home, e.g., Mathematics computer software packages, availability of internet access and ability of the parents to provide computers, software and the internet for their sons. We assess the expected improvement in grades, motivation and communication between home and school. For the teaches', we assess the expected improvement in teachers' productivity, teachers' experience, qualifications in computing and Mathematics packages and their anticipated expectations such as improvement in problem solving, grades of students. Our main objective is to determine the expected results resulting from applying computer software and web-based learning in teaching Mathematics.
Mathematical Biology Modules Based on Modern Molecular Biology and Modern Discrete Mathematics
Robeva, Raina; Davies, Robin; Hodge, Terrell; Enyedi, Alexander
2010-01-01
We describe an ongoing collaborative curriculum materials development project between Sweet Briar College and Western Michigan University, with support from the National Science Foundation. We present a collection of modules under development that can be used in existing mathematics and biology courses, and we address a critical national need to introduce students to mathematical methods beyond the interface of biology with calculus. Based on ongoing research, and designed to use the project-...
Web-Based Mathematics: Some "Dos" and "Don'ts"
Loong, Esther Yook-Kin
2011-01-01
This case study describes an "out of field" teacher's use of the Internet to teach a range of mathematical topics in a modified Year 8 mathematics class. It highlights the importance of three factors for implementing a discernible web-based teaching strategy: appropriate choice of web objects, effective "virtual" pedagogy, and technical support…
Inquiry-Based Learning and the Art of Mathematical Discourse
von Renesse, Christine; Ecke, Volker
2015-01-01
Our particular flavor of inquiry-based learning (IBL) uses mathematical discourse, conversations, and discussions to empower students to deepen their mathematical thinking, building on strengths of students in the humanities. We present an organized catalog of powerful questions, discussion prompts, and talk moves that can help faculty facilitate…
Lev, Felix M.
2014-01-01
Classical mathematics (involving such notions as infinitely small/large and continuity) is usually treated as fundamental while finite mathematics is treated as inferior which is used only in special applications. We first argue that the situation is the opposite: classical mathematics is only a degenerate special case of finite one and finite mathematics is more pertinent for describing nature than standard one. Then we describe results of a quantum theory based on finite mathematics. Implic...
Mathematical modeling of quartz particle melting process in plasma-chemical reactor
Volokitin, Oleg, E-mail: volokitin-oleg@mail.ru; Volokitin, Gennady, E-mail: vgg-tomsk@mail.ru; Skripnikova, Nelli, E-mail: nks2003@mai.ru; Shekhovtsov, Valentin, E-mail: shehovcov2010@yandex.ru [Tomsk State University of Architecture and Building, 2, Solyanaya Sq., 634003, Tomsk (Russian Federation); Vlasov, Viktor, E-mail: rector@tsuab.ru [Tomsk State University of Architecture and Building, 2, Solyanaya Sq., 634003, Tomsk (Russian Federation); National Research Tomsk Polytechnic University, 30, Lenin Ave., 634050, Tomsk (Russian Federation)
2016-01-15
Among silica-based materials vitreous silica has a special place. The paper presents the melting process of a quartz particle under conditions of low-temperature plasma. A mathematical model is designed for stages of melting in the experimental plasma-chemical reactor. As calculation data show, quartz particles having the radius of 0.21≤ r{sub p} ≤0.64 mm completely melt at W = 0.65 l/s particle feed rate depending on the Nusselt number, while 0.14≤ r{sub p} ≤0.44 mm particles melt at W = 1.4 l/s. Calculation data showed that 2 mm and 0.4 mm quartz particles completely melted during and 0.1 s respectively. Thus, phase transformations occurred in silicon dioxide play the important part in its heating up to the melting temperature.
Mathematical modeling of quartz particle melting process in plasma-chemical reactor
Volokitin, Oleg; Vlasov, Viktor; Volokitin, Gennady; Skripnikova, Nelli; Shekhovtsov, Valentin
2016-01-01
Among silica-based materials vitreous silica has a special place. The paper presents the melting process of a quartz particle under conditions of low-temperature plasma. A mathematical model is designed for stages of melting in the experimental plasma-chemical reactor. As calculation data show, quartz particles having the radius of 0.21≤ rp ≤0.64 mm completely melt at W = 0.65 l/s particle feed rate depending on the Nusselt number, while 0.14≤ rp ≤0.44 mm particles melt at W = 1.4 l/s. Calculation data showed that 2 mm and 0.4 mm quartz particles completely melted during and 0.1 s respectively. Thus, phase transformations occurred in silicon dioxide play the important part in its heating up to the melting temperature.
Mathematical modeling of quartz particle melting process in plasma-chemical reactor
Among silica-based materials vitreous silica has a special place. The paper presents the melting process of a quartz particle under conditions of low-temperature plasma. A mathematical model is designed for stages of melting in the experimental plasma-chemical reactor. As calculation data show, quartz particles having the radius of 0.21≤ rp ≤0.64 mm completely melt at W = 0.65 l/s particle feed rate depending on the Nusselt number, while 0.14≤ rp ≤0.44 mm particles melt at W = 1.4 l/s. Calculation data showed that 2 mm and 0.4 mm quartz particles completely melted during and 0.1 s respectively. Thus, phase transformations occurred in silicon dioxide play the important part in its heating up to the melting temperature
Mathematical Formulation of DMH-Based Inverse Optimization
Mihaylov, Ivaylo B.; Moros, Eduardo G.
2014-01-01
Purpose: To introduce the concept of dose–mass-based inverse optimization for radiotherapy applications. Materials and Methods: Mathematical derivation of the dose–mass-based formalism is presented. This mathematical representation is compared to the most commonly used dose–volume-based formulation used in inverse optimization. A simple example on digitally created phantom is presented. The phantom consists of three regions: a target surrounded by high- and low-density regions. The target ...
Mathematical modeling of the radiation-chemical behavior of Np(VI) in HNO3
The literature contains many studies on the radiolytic behavior of Np(VI) in HNO3 solutions. These studies have been partially reviewed in a book. An attempt has been made to examine the mechanism of the radiation-chemical conversion of Np ions. However, the kinetic laws cannot be obtained and the mechanism of the reactions occurring cannot be accurately found without mathematical modeling. Mathematical modeling of the radiation-chemical behavior of Np(VI) in 0.5-6 M HNO3 is reported in the present article. Calculations using a special program were performed on an IBM PC/X5 personal computer
Akiba, Motoko; Chiu, Ya-Fang; Zhuang, Yue-Lin; Mueller, Heather E.
2008-01-01
Using the NAEP nationally-representative data collected from eighth-graders, we investigated the relative exposure of American Indian/Alaska Native (AIAN) students to mathematics teachers who are knowledgeable about standards, participate in standards-based professional development, and practice standards-based instruction; American Indian/Alaska…
Mathematical model on surface reaction diffusion in the presence of front chemical reaction
Permikin, D. V.; Zverev, V. S.
2013-01-01
The article discusses a mathematical model of solid-phase diffusion over substance surface accompanied a frontal chemical reaction. The purpose of our article is to describe the concentration distribution and surface reacted layer growth. The model is a system parabolic equations, complicated with the presence of mobile front. It takes account of diffusive fluxes redistribution, sublimation from the surface, chemical reaction reversibility. The asymptotic approximation of the obtained nonline...
A mathematical model for the transport and fate of organic chemicals in unsaturated/saturated soils.
Lindstrom, F T; Piver, W T
1985-01-01
A mathematical model, simulating the transport and fate of nonionizable organic compounds in unsaturated/saturated porous media (soils) in a terrestrial microcosm has been developed. Using the principles of water mass, momentum, heat energy and chemical mass balance, the three fields: moisture, temperature, and liquid phase chemical concentration are solved for simultaneously by coupling the soil slab to an environmentally realistic air-soil interface (a dynamic free boundary) conditions and ...
A New Activity-Based Cost (ABC) Mathematical Model
JIANG Shuo; SONG Lei
2003-01-01
Along with the product price competition growing intensely, it is apparently important for reasonably distributing and counting cost. But, in sharing indirect cost, traditional cost accounting unveils the limitations increasingly, especially in authenticity of cost information. And the accounting theory circles and industry circles begin seeking one kind of new accurate cost calculation method, and the activity-based cost (ABC) method emerges as the times require. In this paper, we will build its mathematical model by the basic principle of ABC, and will improve its mathematical model further. We will establish its comparison mathematical model and make the ABC method go a step further to its practical application.
Stein, Sherman K
2010-01-01
Anyone can appreciate the beauty, depth, and vitality of mathematics with the help of this highly readable text, specially developed from a college course designed to appeal to students in a variety of fields. Readers with little mathematical background are exposed to a broad range of subjects chosen from number theory, topology, set theory, geometry, algebra, and analysis. Starting with a survey of questions on weight, the text discusses the primes, the fundamental theorem of arithmetic, rationals and irrationals, tiling, tiling and electricity, probability, infinite sets, and many other topi
The 1988 progress report of the Mathematics center (Polytechnic School, France), is presented. The Center is composed of different research teams: analysis, Riemann geometry, group theory, formal calculus and algorithm geometry, dynamical systems, topology and singularity. For each team, the members, the research topics, the national and international cooperations, are given. The papers concerning the investigations carried out in 1988, are listed
Intelligent Forecasting of Sintered Ore's Chemical Components Based on SVM
ZHONG Luo; WANG Qingbo; YUAN Jingling
2011-01-01
Using object mathematical model of traditional control theory can not solve the forecasting problem of the chemical components of sintered ore. In order to control complicated chemical components in the manufacturing process of sintered ore, some key techniques for intelligent forecasting of the chemical components of sintered ore are studied in this paper. A new intelligent forecasting system based on SVM is proposed and realized. The results show that the accuracy of predictive value of every component is more than 90%. The application of our system in related companies is for more than one year and has shown satisfactory results.
Resilience of chemical industrial areas through attenuation-based security
This paper investigates the possibility of attenuation-based security within chemical industrial areas. Representing chemical industrial areas as mathematical networks, we prove by case-study that the resilience to disaster of such areas may follow a power-law distribution. Furthermore, we examine what happens to the network when highly hazardous installations would be intelligently protected against malicious acts: the network disintegrates into separate smaller networks. Hence, islands are formed with no escalation danger in between. We conclude that it is possible to protect chemical industrial areas in such a way that they are more resilient against terrorism
Problem-based learning and teacher training in mathematics
Cazzola, Marina
2008-01-01
Problem-based learning (PBL) is a constructivist learner-centered instructional approach based on the analysis, resolution and discussion of a given problem. It can be applied to any subject, indeed it is especially useful for the teaching of mathematics. When compared to ``traditional'' teaching, the PBL approach requires increased responsibility for the teachers (in addition to the presentation of mathematical knowledge, they need to engage students in gathering information and using their knowledge to solve given problems). It thus become crucial that the future teachers become aware of its effectiveness. One of the main obstacle to this awareness lies usually on the fact that future teachers did not find this methodology in their own pre-service training. In this paper we will describe the attempt to introduce PBL in University courses so to have future maths teacher ``experience mathematics'' themselves.
Mathematical model of non-isothermal creep based anisotropic damage
Галаган, Ю. Н.; Лысенко, С. В.; Львов, Г. И.
2008-01-01
А mathematical model of nonisothermic creep for anisotropic damage case is considered. Constitutive relation of creep rate and kinematic equation of damage evolution are assumed temperature dependent. A second range tensor is used for description damage. A technique based on existing experimental curves for the identification of material creep constants is presented.
Discipline-Based Remediation: Bridging the Mathematics Gap
Wenner, Jennifer M.; Baer, Eric M.; Burn, Helen E.
2013-10-01
Geoscience relies on numbers, data, equations, graphical representations, and other quantitative skills; therefore, introductory geoscience courses need to accurately portray the science as quantitative [e.g., Wenner et al., 2009]. However, up to 57% of students arrive at college underprepared to perform mathematics at the level necessary to succeed in introductory courses [ACT, 2011]. Although some institutions have turned to prerequisites as a way to ensure appropriate preparation, these extra courses can place undue financial, temporal, and academic burdens on interested students, keeping them from enrolling in science courses that may interest them. As an alternative to mathematics prerequisites, geoscience faculty at the University of Wisconsin Oshkosh and Highline Community College in Des Moines, Wash., funded by the National Science Foundation, developed a model of successful integration of discipline-based mathematics remediation into an introductory geoscience course: The Math You Need, When You Need It (TMYN; http://serc.carleton.edu/mathyouneed/).
Palinussa, Anderson L.
2013-01-01
This paper presents the findings of a quasi-experimental with pre-test-post-test design and control group that aims to assess students' critical mathematical thinking skills and character through realistic mathematics education (RME) culture-based. Subjects of this study were 106 junior high school students from two low and medium schools level in…
A mathematical model for targeting chemicals to tissues by exploiting complex degradation
Grodzinsky Alan J
2011-09-01
Full Text Available Abstract Background In many biological and therapeutic contexts, it is highly desirable to target a chemical specifically to a particular tissue where it exerts its biological effect. In this paper, we present a simple, generic, mathematical model that elucidates a general method for targeting a chemical to particular tissues. The model consists of coupled reaction-diffusion equations to describe the evolution within the tissue of the concentrations of three chemical species: a (concentration of free chemical, b (binding protein and their complex, c (chemical bound to binding protein. We assume that all species are free to diffuse, and that a and b undergo a reversible reaction to form c. In addition, the complex, c, can be broken down by a process (e.g. an enzyme in the tissue that results in the release of the chemical, a, which is then free to exert its biological action. Results For simplicity, we consider a one-dimensional geometry. In the special case where the rate of complex formation is small (compared to the diffusion timescale of the species within the tissue the system can be solved analytically. This analytic solution allows us to show how the concentration of free chemical, a, in the tissue can be increased over the concentration of free chemical at the tissue boundary. We show that, under certain conditions, the maximum concentration of a can occur at the centre of the tissue, and give an upper bound on this maximum level. Numerical simulations are then used to determine how the behaviour of the system changes when the assumption of negligible complex formation rate is relaxed. Conclusions We have shown, using our mathematical model, how complex degradation can potentially be exploited to target a chemical to a particular tissue, and how the level of the active chemical depends on factors such as the diffusion coefficients and degradation/production rates of each species. The biological significance of these results in terms of
Semantic Web Based Efficient Search Using Ontology and Mathematical Model
K.Palaniammal
2014-01-01
Full Text Available The semantic web is the forthcoming technology in the world of search engine. It becomes mainly focused towards the search which is more meaningful rather than the syntactic search prevailing now. This proposed work concerns about the semantic search with respect to the educational domain. In this paper, we propose semantic web based efficient search using ontology and mathematical model that takes into account the misleading, unmatched kind of service information, lack of relevant domain knowledge and the wrong service queries. To solve these issues in this framework is designed to make three major contributions, which are ontology knowledge base, Natural Language Processing (NLP techniques and search model. Ontology knowledge base is to store domain specific service ontologies and service description entity (SDE metadata. The search model is to retrieve SDE metadata as efficient for Education lenders, which include mathematical model. The Natural language processing techniques for spell-check and synonym based search. The results are retrieved and stored in an ontology, which in terms prevents the data redundancy. The results are more accurate to search, sensitive to spell check and synonymous context. This paper reduces the user’s time and complexity in finding for the correct results of his/her search text and our model provides more accurate results. A series of experiments are conducted in order to respectively evaluate the mechanism and the employed mathematical model.
Wardono; Waluya, S. B.; Mariani, Scolastika; Candra D, S.
2016-02-01
This study aims to find out that there are differences in mathematical literacy ability in content Change and Relationship class VII Junior High School 19, Semarang by Problem Based Learning (PBL) model with an Indonesian Realistic Mathematics Education (called Pendidikan Matematika Realistik Indonesia or PMRI in Indonesia) approach assisted Elearning Edmodo, PBL with a PMRI approach, and expository; to know whether the group of students with learning PBL models with PMRI approach and assisted E-learning Edmodo can improve mathematics literacy; to know that the quality of learning PBL models with a PMRI approach assisted E-learning Edmodo has a good category; to describe the difficulties of students in working the problems of mathematical literacy ability oriented PISA. This research is a mixed methods study. The population was seventh grade students of Junior High School 19, Semarang Indonesia. Sample selection is done by random sampling so that the selected experimental class 1, class 2 and the control experiment. Data collected by the methods of documentation, tests and interviews. From the results of this study showed average mathematics literacy ability of students in the group PBL models with a PMRI approach assisted E-learning Edmodo better than average mathematics literacy ability of students in the group PBL models with a PMRI approach and better than average mathematics literacy ability of students in the expository models; Mathematics literacy ability in the class using the PBL model with a PMRI approach assisted E-learning Edmodo have increased and the improvement of mathematics literacy ability is higher than the improvement of mathematics literacy ability of class that uses the model of PBL learning with PMRI approach and is higher than the improvement of mathematics literacy ability of class that uses the expository models; The quality of learning using PBL models with a PMRI approach assisted E-learning Edmodo have very good category.
Filler segmentation of SEM paper images based on mathematical morphology.
Ait Kbir, M; Benslimane, Rachid; Princi, Elisabetta; Vicini, Silvia; Pedemonte, Enrico
2007-07-01
Recent developments in microscopy and image processing have made digital measurements on high-resolution images of fibrous materials possible. This helps to gain a better understanding of the structure and other properties of the material at micro level. In this paper SEM image segmentation based on mathematical morphology is proposed. In fact, paper models images (Whatman, Murillo, Watercolor, Newsprint paper) selected in the context of the Euro Mediterranean PaperTech Project have different distributions of fibers and fillers, caused by the presence of SiAl and CaCO3 particles. It is a microscopy challenge to make filler particles in the sheet distinguishable from the other components of the paper surface. This objectif is reached here by using switable strutural elements and mathematical morphology operators. PMID:17867540
Image Filtering Based on Mathematical Morphology and Visual Perception Principle
JINGXiaojun; YUNong; SHANGYong
2004-01-01
The operation of a morphological filter can be divided into two basic problems that include morphological operation and Structuring element (SE) selection. The rules for morphological operations are predefined, so the filter's properties depend merely on the selection of SE. How to design adaptively the optimal morphological filter so as to automatically and delicately complete the tasks of target detection and recognition, becomes one of the current research hotspots and subtle technical problems. Based on the filtering theory of the mathematical morphology, by introducing appropriate visual perception principle, this paper presents how to design the filtering architecture and its target detection model through the optimal parameter training. By this way it can provide good detection results and robust adaptability to image targets with clutter background. It is sure to provide a new approach to automatic target recognition with mathematical morphology theory.
Engaging Future Teachers in Problem-Based Learning with the Park City Mathematics Institute Problems
Pilgrim, Mary E.
2014-01-01
Problem-based learning (PBL) is a pedagogical technique recommended for K-12 mathematics classrooms. However, the mathematics courses in future teachers' degree programs are often lecture based. Students typically learn about problem-based learning in theory, but rarely get to experience it first-hand in their mathematics courses. The premise…
Kiil, Søren
2011-01-01
A mathematical model, describing the curing behaviour of a two-component, solvent-based, thermoset coating, is used to conduct a parameter study. The model includes curing reactions, solvent intra-film diffusion and evaporation, film gelation, vitrification, and crosslinking. A case study with a...... concentration of solvent. Simulations of solvent evaporation are compared to experimental data from a previous investigation. As part of the parameter study, mechanisms of this complex coating system are discussed....
Modelling Amperometric Biosensors Based on Chemically Modified Electrodes
Baronas, Romas; Kulys, Juozas
2008-01-01
The response of an amperometric biosensor based on a chemically modified electrode was modelled numerically. A mathematical model of the biosensor is based on a system of non-linear reaction-diffusion equations. The modelling biosensor comprises two compartments: an enzyme layer and an outer diffusion layer. In order to define the main governing parameters the corresponding dimensionless mathematical model was derived. The digital simulation was carried out using the finite difference technique. The adequacy of the model was evaluated using analytical solutions known for very specific cases of the model parameters. By changing model parameters the output results were numerically analyzed at transition and steady state conditions. The influence of the substrate and mediator concentrations as well as of the thicknesses of the enzyme and diffusion layers on the biosensor response was investigated. Calculations showed complex kinetics of the biosensor response, especially when the biosensor acts under a mixed limitation of the diffusion and the enzyme interaction with the substrate.
PREFACE: Physics-Based Mathematical Models for Nanotechnology
Voon, Lok C. Lew Yan; Melnik, Roderick; Willatzen, Morten
2008-03-01
stain-resistant clothing, but with thousands more anticipated. The focus of this interdisciplinary workshop was on determining what kind of new theoretical and computational tools will be needed to advance the science and engineering of nanomaterials and nanostructures. Thanks to the stimulating environment of the BIRS, participants of the workshop had plenty of opportunity to exchange new ideas on one of the main topics of this workshop—physics-based mathematical models for the description of low-dimensional semiconductor nanostructures (LDSNs) that are becoming increasingly important in technological innovations. The main objective of the workshop was to bring together some of the world leading experts in the field from each of the key research communities working on different aspects of LDSNs in order to (a) summarize the state-of-the-art models and computational techniques for modeling LDSNs, (b) identify critical problems of major importance that require solution and prioritize them, (c) analyze feasibility of existing mathematical and computational methodologies for the solution of some such problems, and (d) use some of the workshop working sessions to explore promising approaches in addressing identified challenges. With the possibility of growing practically any shape and size of heterostructures, it becomes essential to understand the mathematical properties of quantum-confined structures including properties of bulk states, interface states, and surface states as a function of shape, size, and internal strain. This workshop put strong emphasis on discussions of the new mathematics needed in nanotechnology especially in relation to geometry and material-combination optimization of device properties such as electronic, optical, and magnetic properties. The problems that were addressed at this meeting are of immense importance in determining such quantum-mechanical properties and the group of invited participants covered very well all the relevant disciplines
Aldona Krupska
2015-06-01
In this paper the arduous attempt to find a mathematical solution for the nonlinear autocatalytic chemical processes with a time-varying and oscillating inflow of reactant to the reaction medium has been taken. Approximate analytical solution is proposed. Numerical solutions and analytical attempts to solve the non-linear differential equation indicates a phase shift between the oscillatory influx of intermediate reaction reagent to the medium of chemical reaction and the change of its concentration in this medium. Analytical solutions indicate that this shift may be associated with the reaction rate constants 1 and 2 and the relaxation time . The relationship between the phase shift and the oscillatory flow of reactant seems to be similar to that obtained in the case of linear chemical reactions, as described previously, however, the former is much more complex and different. In this paper, we would like to consider whether the effect of forced phase shift in the case of nonlinear and non-oscillatory chemical processes occurring particularly in the living systems have a practical application in laboratory.
Ottmar, Erin R.; Rimm-Kaufman, Sara E.; Larsen, Ross A.; Berry, Robert Q.
2015-01-01
This study investigates the effectiveness of the Responsive Classroom (RC) approach, a social and emotional learning intervention, on changing the relations between mathematics teacher and classroom inputs (mathematical knowledge for teaching [MKT] and standards-based mathematics teaching practices) and student mathematics achievement. Work was…
Anderson L. Palinussa
2013-01-01
This paper presents the findings of a quasi-experimental with pre-testpost-test design and control group that aims to assess students’ critical mathematical thinking skills and character through realisticmathematics education (RME) culture-based. Subjects of this studywere 106 junior high school students from two low and medium schools level in Ambon. The instruments of the study are: students’ early math skills test, critical thinking skills mathematical test and perception scale of students...
Mathematical model for light scanning system based on circular laser
Peiquan Xu; Shun Yao; Fenggui Lu; Xinhua Tang; Wei Zhang
2005-01-01
A novel light scanning system based on circular laser trajectory for welding robot is developed. With the help of image processing technique, intelligent laser welding could be realized. According to laser triangulation algorithm and Scheimpflug condition, mathematical model for circular laser vision is built.This scanning system projects circular laser onto welded seams and recovers the depth of the welded seams,escapes from shortcomings of less information, explains ambiguity and single tracking direction inherent in "spot" or "line" type laser trajectory. Three-dimensional (3D) model for welded seams could be recognized after depth recovery. The imaging error is investigated also.
Nonlinear State Estimation with Missing Observations Based on Mathematical Programming
Pavelková, Lenka
Praha : ÚTIA AV ČR, 2010 - (Janžura, M.; Ivánek, J.). s. 23-23 [6th International Workshop on Data – Algorithms – Decision Making. 02.12.2010-04.12.2010, Jindřichův Hradec] R&D Projects: GA MŠk 1M0572 Institutional research plan: CEZ:AV0Z10750506 Keywords : state filtering * bounded errors * missing measurements Subject RIV: BC - Control Systems Theory http://library.utia.cas.cz/separaty/2010/AS/pavelkova-nonlinear state estimation with missing observations based on mathematical programming .pdf
Inquiry-based mathematics teaching: The case of Célia.
Menezes, Luis; Oliveira, Hélia; Canavarro, Ana Paula
2015-01-01
This chapter discusses the instructional practice of a primary school teacher. It is based on a framework that we developed in the project “Professional Practices of Mathematics Teachers”, which relates the teacher’s intentions to her actions in an inquiry-based mathematics classroom. The framework covers the promotion of mathematics learning as well as the class management. It details the instructional actions of the teacher in terms of the launching of the mathematical tas...
A cellular automata-based mathematical model for thymocyte development.
Hallan Souza-e-Silva
Full Text Available Intrathymic T cell development is an important process necessary for the normal formation of cell-mediated immune responses. Importantly, such a process depends on interactions of developing thymocytes with cellular and extracellular elements of the thymic microenvironment. Additionally, it includes a series of oriented and tunely regulated migration events, ultimately allowing mature cells to cross endothelial barriers and leave the organ. Herein we built a cellular automata-based mathematical model for thymocyte migration and development. The rules comprised in this model take into account the main stages of thymocyte development, two-dimensional sections of the normal thymic microenvironmental network, as well as the chemokines involved in intrathymic cell migration. Parameters of our computer simulations with further adjusted to results derived from previous experimental data using sub-lethally irradiated mice, in which thymus recovery can be evaluated. The model fitted with the increasing numbers of each CD4/CD8-defined thymocyte subset. It was further validated since it fitted with the times of permanence experimentally ascertained in each CD4/CD8-defined differentiation stage. Importantly, correlations using the whole mean volume of young normal adult mice revealed that the numbers of cells generated in silico with the mathematical model fall within the range of total thymocyte numbers seen in these animals. Furthermore, simulations made with a human thymic epithelial network using the same mathematical model generated similar profiles for temporal evolution of thymocyte developmental stages. Lastly, we provided in silico evidence that the thymus architecture is important in the thymocyte development, since changes in the epithelial network result in different theoretical profiles for T cell development/migration. This model likely can be used to predict thymocyte evolution following therapeutic strategies designed for recovery of the
Unraveling the Culture of the Mathematics Classroom: A Video-Based Study in Sixth Grade
Depaepe, Fien; De Corte, Erik; Verschaffel, Lieven
2007-01-01
Changing perspectives on mathematics teaching and learning resulted in a new generation of mathematics textbooks, stressing among others the importance of mathematical reasoning and problem-solving skills and their application to real-life situations. The article reports a study that investigates to what extent the reform-based ideas underlying…
A MATLAB-Aided Method for Teaching Calculus-Based Business Mathematics
Liang, Jiajuan; Pan, William S. Y.
2009-01-01
MATLAB is a powerful package for numerical computation. MATLAB contains a rich pool of mathematical functions and provides flexible plotting functions for illustrating mathematical solutions. The course of calculus-based business mathematics consists of two major topics: 1) derivative and its applications in business; and 2) integration and its…
Yüksel, Ismail
2014-01-01
The aim of this paper is to examine the impact of activity-based mathematics instruction on mathematics performance and investigate those factors, which contribute to the mathematics performance of a sample of children aged between 10 and 12 years. The study was designed to consider the impact of prior knowledge, self-regulation, prior attitude,…
Butkovich, Nancy J.
2015-01-01
Doctoral candidates may request short-term embargoes on the release of their dissertations in order to apply for patents. This study examines how often inventions described in dissertations in chemical engineering, chemistry, physics, and mathematics are converted into U.S. patent applications, as well as the relationship between dissertation…
Nanotube-Based Chemical and Biomolecular Sensors
J.Koh; B.Kim; S.Hong; H.Lim; H.C.Choi
2008-01-01
We present a brief review about recent results regarding carbon nanotube (CNT)-based chemical and biomolecular sensors. For the fabrication of CNT-based sensors, devices containing CNT channels between two metal electrodes are first fabricated usually via chemical vapor deposition (CVD) process or "surface programmed assembly" method. Then, the CNT surfaces are often functionalized to enhance the selectivity of the sensors. Using this process, highly-sensitive CNT-based sensors can be fabricated for the selective detection of various chemical and biological molecules such as hydrogen, ammonia, carbon monoxide, chlorine gas, DNA, glucose, alcohol, and proteins.
Mathematical Biology Modules Based on Modern Molecular Biology and Modern Discrete Mathematics
Robeva, Raina; Davies, Robin; Hodge, Terrell; Enyedi, Alexander
2010-01-01
We describe an ongoing collaborative curriculum materials development project between Sweet Briar College and Western Michigan University, with support from the National Science Foundation. We present a collection of modules under development that can be used in existing mathematics and biology courses, and we address a critical national need to…
Marković Jelena Đ.
2009-01-01
Full Text Available Membrane process efficiency in the dairy industry is impaired by the formation of deposits during filtration processes. This work describes cleaning procedures for ceramic tubular membrane (50 nm fouled with whey proteins. Also, mathematical modelling was performed to obtain models which allow deeper insight into the mechanisms involved during cleaning procedures. The caustic solutions (0.2%w/w, 0.4%w/w and 1.0%w/w NaOH and the mixture of two commercial detergents (0.8%w/w P3-ultrasil 69+0.5% w/w P3-ultrasil 67 and 1.2% P3-ultrasil 69+0.75 P3-ultrasil 67 were used as chemical cleaning agents. The results showed that the best flux recovery was achieved with 0.4%w/w NaOH solution. After analyzing the experimental data, five parameter and six parameter kinetic models were suggested for alkali and detergent cleaning, respectively. The changes of total and specific resistances, as well as the change of the effective pore diameter and deposit thickness during cleaning are estimated by applying these models.
Computer-Based Mathematics Instructions for Engineering Students
Khan, Mustaq A.; Wall, Curtiss E.
1996-01-01
Almost every engineering course involves mathematics in one form or another. The analytical process of developing mathematical models is very important for engineering students. However, the computational process involved in the solution of some mathematical problems may be very tedious and time consuming. There is a significant amount of mathematical software such as Mathematica, Mathcad, and Maple designed to aid in the solution of these instructional problems. The use of these packages in classroom teaching can greatly enhance understanding, and save time. Integration of computer technology in mathematics classes, without de-emphasizing the traditional analytical aspects of teaching, has proven very successful and is becoming almost essential. Sample computer laboratory modules are developed for presentation in the classroom setting. This is accomplished through the use of overhead projectors linked to graphing calculators and computers. Model problems are carefully selected from different areas.
Keyword and image-based retrieval of mathematical expressions
Zanibbi, Richard; Yuan, Bo
2011-01-01
Two new methods for retrieving mathematical expressions using conventional keyword search and expression images are presented. An expression-level TF-IDF (term frequency-inverse document frequency) approach is used for keyword search, where queries and indexed expressions are represented by keywords taken from LATEX strings. TF-IDF is computed at the level of individual expressions rather than documents to increase the precision of matching. The second retrieval technique is a form of Content-Based Image Retrieval (CBIR). Expressions are segmented into connected components, and then components in the query expression and each expression in the collection are matched using contour and density features, aspect ratios, and relative positions. In an experiment using ten randomly sampled queries from a corpus of over 22,000 expressions, precision-at-k (k = 20) for the keyword-based approach was higher (keyword: μ = 84.0, σ = 19.0, imagebased: μ = 32.0, σ = 30.7), but for a few of the queries better results were obtained using a combination of the two techniques.
Hodges, Thomas E.; Jong, Cindy
2014-01-01
The authors drew upon Remillard and Bryans' categorization of curriculum use in observating two middle-grade teachers' integration of Standards-based curriculum materials produced by the National Council of Teachers of Mathematics. Each teacher participated in a two-year professional development program focused on increasing content knowledge and…
Smith, Glenn Gordon; Ferguson, David; Caris, Mieke
2003-01-01
This study examined the instructor experience of teaching college courses (discussion-based and mathematics) over the Web, versus in the classroom, in terms of teaching, social issues, and emergent issues such as media effects. We interviewed, by e-mail and telephone, 22 college instructors who taught in both formats. We categorized interview…
Material Encounters with Mathematics: The Case for Museum Based Cross-Curricular Integration
de Freitas, Elizabeth; Bentley, Sean J.
2012-01-01
This paper reports on research from a network of high school and museum partnerships designed to explore techniques for integrating mathematics and physics learning experiences during the first year of high school. The foundation of the curriculum is a problem-based, museum-based, and hands-on approach to mathematics and physics. In this paper, we…
Mathematical model for flood routing based on cellular automaton
Xin CAI
2014-04-01
Full Text Available Increasing frequency and severity of flooding have caused tremendous damage in China, requiring more essential countermeasures to alleviate the damage. In this study, the dynamic simulation property of a cellular automaton was used to make further progress in flood routing. In consideration of terrain’s influence on flood routing, we regarded the terrain elevation as an auxiliary attribute of a two-dimensional cellular automaton in path selection for flood routing and developed a mathematical model based on a cellular automaton. A numerical case of propagation of an outburst flood in an area of the lower Yangtze River was analyzed with both the fixed-step and variable-step models. The results show that the flood does not spread simultaneously in all directions, but flows into the lower place first, and that the submerged area grows quickly at the beginning, but slowly later on. The final submerged areas obtained from the two different models are consistent, and the flood volume balance test shows that the flood volume meets the requirement of the total volume balance. The analysis of the case shows that the proposed model can be a valuable tool for flood routing.
Potential Accessibility of Web-based mathematical information resources
Centelles Velilla, Miquel; Ribera, Mireia; Rodríguez Santiago, Inmaculada
2014-01-01
This paper presents a research concerning the conversion of non-accessible web pages containing mathematical formulae into accessible versions through an OCR (Optical Character Recognition) tool. The objective of this research is twofold. First, to establish criteria for evaluating the potential accessibility of mathematical web sites, i.e. the feasibility of converting non-accessible (non-MathML) math sites into accessible ones (Math-ML). Second, to propose a data model and a mechanism to pu...
The mathematical investigation of the work of enzyme biosensors based on conductive polymers
Valentynovych Tkach, Volodymyr; Vasyl´ovych Nechyporuk, Vasyl´; Ivanovych Yagodynets, Petro
2012-01-01
The work of CP-based biosensors was described mathematically in potentiostatic and potentiodynamic mode with constant voltage was mathematically described. The mathematical models were analyzed by linear-stability theory and bifurcation analysis. The stable-state conditions were derived by using the stable-state requirements for 2-dimensional systems (for the potentiostatic mode) and Routh-Hurwitz criterion (for the potentiodynamic mode). The causes for the oscillatory behavior are the influe...
Modelling Amperometric Biosensors Based on Chemically Modified Electrodes
Juozas Kulys
2008-08-01
Full Text Available The response of an amperometric biosensor based on a chemically modified electrode was modelled numerically. A mathematical model of the biosensor is based on a system of non-linear reaction-diffusion equations. The modelling biosensor comprises two compartments: an enzyme layer and an outer diffusion layer. In order to define the main governing parameters the corresponding dimensionless mathematical model was derived. The digital simulation was carried out using the finite difference technique. The adequacy of the model was evaluated using analytical solutions known for very specific cases of the model parameters. By changing model parameters the output results were numerically analyzed at transition and steady state conditions. The influence of the substrate and mediator concentrations as well as of the thicknesses of the enzyme and diffusion layers on the biosensor response was investigated. Calculations showed complex kinetics of the biosensor response, especially when the biosensor acts under a mixed limitation of the diffusion and the enzyme interaction with the substrate.
Design of greenbelt for an industrial complex based on mathematical modelling.
Khan, F I; Abbasi, S A
2002-07-01
Greenbelt is a strip of vegetation for which species of trees and shrubs are scientifically chosen and planted to serve a designated purpose such as control of wind erosion, of dust, of noise etc. In the context of air pollution attenuation, greenbelts must be developed around a source of air pollutant in a manner so as to effectively reduce the pollution caused by that source. Design of effective greenbelts involves consideration of meteorological, physico-chemical, biological, and horticultural aspects relevant to pollutant source and the area where greenbelt has to be established. These authors have recently developed mathematical models for effective design of greenbelts. This paper presents an overview of the methodology based on the models, and describes a case study in which the methodology has been applied to design a greenbelt for a real-life situation. PMID:12164640
Edwin Musdi
2016-02-01
Full Text Available This research aims to develop a mathematics instructional model based realistic mathematics education (RME to promote students' problem-solving abilities. The design research used Plomp models, which consists of preliminary phase, development or proto-typing phase and assessment phase. At this study, only the first two phases conducted. The first phase, a preliminary investigation, carried out with a literature study to examine the theory-based instructional learning RME model, characteristics of learners, learning management descriptions by junior high school mathematics teacher and relevant research. The development phase is done by developing a draft model (an early prototype model that consists of the syntax, the social system, the principle of reaction, support systems, and the impact and effects of instructional support. Early prototype model contain a draft model, lesson plans, worksheets, and assessments. Tesssmer formative evaluation model used to revise the model. In this study only phase of one to one evaluation conducted. In the ppreliminary phase has produced a theory-based learning RME model, a description of the characteristics of learners in grade VIII Junior High School Padang and the description of teacher teaching in the classroom. The result showed that most students were still not be able to solve the non-routine problem. Teachers did not optimally facilitate students to develop problem-solving skills of students. It was recommended that the model can be applied in the classroom.
Development and Evaluation of Consumer-Based Mathematics Materials in Adult Basic Education.
Campbell, Patricia F.; Kulm, Gerald
1980-01-01
In creating mathematics materials for adult basic education students, researchers (1) interviewed students and teachers to determine needs and objectives; (2) developed materials based on consumer mathematics skills; and (3) evaluated effectiveness by a pretest/posttest and student, teacher, and administrator questionnaires. Results showed the…
Huang, Tzu-Hua; Liu, Yuan-Chen; Chang, Hsiu-Chen
2012-01-01
This study developed a computer-assisted mathematical problem-solving system in the form of a network instruction website to help low-achieving second- and third-graders in mathematics with word-based addition and subtraction questions in Taiwan. According to Polya's problem-solving model, the system is designed to guide these low-achievers…
Effect of Digital Game Based Learning on Ninth Grade Students' Mathematics Achievement
Swearingen, Dixie K.
2011-01-01
This experimental study examined the effect of an educational massive multiplayer online game (MMOG) on achievement on a standards-based mathematics exam. It also examined the interaction of student characteristics (gender and socioeconomic status) with digital game play on mathematics achievement. Two hundred eighty ninth grade students from a…
An Excel-Aided Method for Teaching Calculus-Based Business Mathematics
Liang, Jiajuan; Martin, Linda
2008-01-01
Calculus-based business mathematics is a required quantitative course for undergraduate business students in most AACSB accredited schools or colleges of business. Many business students, however, have relatively weak mathematical background or even display math-phobia when presented with calculus problems. Because of the popularity of Excel, its…
Alexey M. Lipanov
1997-10-01
Full Text Available In this paper, the laws of the unstable wave processes accompanying the combustion abnormal mode in the large-sized solid propellant rocket motor {SPRM pyrotechnical ignition system {IS are investigated by numerical method. The IS contains the main {cylindrical channel (MC having uniform perforation over the lateral surface, The left MC boundary is blocked and the right boundary is uniformly perforated. The whole perforation is hermetically sealed from outside. The additional {cylindrical channel {AC {an initial impulse amplifier with uniform perforation over the lateral surface is installed into the MC cavity, coaxially to MC. The right AC boundary is blocked, and the time-varying high-temperature gas flow, containing incandescent 'particles is supplied from initiator, equipped with a fast burning compound, through AC left perforated boundary. To imitate the exploitation conditions, the IS is placed in cylindrical imitation chamber {imitative SPRM. In a number of cases, before the beginning of the IS operation, a situation can be realised when the pelletised solid propellant {PSP mass is non-uniformly distributed along the IS AC length, and the greater part of the AC lateral perforation is blocked by the PSP inserted in the IS MC. Under these conditions, the effect of abnormal strengthening of the pressure waves at the AC boundaries is possible. For describing the abnormal nonstationary physico-chemical processes, a mathematical model is developed. For the check-up of this complex model, the numerical calculation results have been compared with the results of the fire stand tests for the regular IS and the engine. The numerical analysis of the unstable wave process development in the AC has shown that the rise of the pressure with an ever increasing amplitude is realised at the moment, when a shock wave reflects alternately, on the left and on the right AC boundaries. The effect of the pressure waves' abnormal strengthening can result in the
Use of PC Based Mathematics Software in the Undergraduate Curriculum.
Slaughter, Joseph M.; And Others
1991-01-01
Three mathematics software packages, MathCAD, Point Five, and TK Solver Plus, are described and compared. The packages were rated on the accompanying documentation, ease of learning, ease of use, matrix operations, equation solving capability, versatility, use of units, generation of graphs and tables, readability of output, and overall…
Chemical Sensors Based on Optical Ring Resonators
Homer, Margie; Manfreda, Allison; Mansour, Kamjou; Lin, Ying; Ksendzov, Alexander
2005-01-01
Chemical sensors based on optical ring resonators are undergoing development. A ring resonator according to this concept is a closed-circuit dielectric optical waveguide. The outermost layer of this waveguide, analogous to the optical cladding layer on an optical fiber, is a made of a polymer that (1) has an index of refraction lower than that of the waveguide core and (2) absorbs chemicals from the surrounding air. The index of refraction of the polymer changes with the concentration of absorbed chemical( s). The resonator is designed to operate with relatively strong evanescent-wave coupling between the outer polymer layer and the electromagnetic field propagating along the waveguide core. By virtue of this coupling, the chemically induced change in index of refraction of the polymer causes a measurable shift in the resonance peaks of the ring. In a prototype that has been used to demonstrate the feasibility of this sensor concept, the ring resonator is a dielectric optical waveguide laid out along a closed path resembling a racetrack (see Figure 1). The prototype was fabricated on a silicon substrate by use of standard techniques of thermal oxidation, chemical vapor deposition, photolithography, etching, and spin coating. The prototype resonator waveguide features an inner cladding of SiO2, a core of SixNy, and a chemical-sensing outer cladding of ethyl cellulose. In addition to the ring Chemical sensors based on optical ring resonators are undergoing development. A ring resonator according to this concept is a closed-circuit dielectric optical waveguide. The outermost layer of this waveguide, analogous to the optical cladding layer on an optical fiber, is a made of a polymer that (1) has an index of refraction lower than that of the waveguide core and (2) absorbs chemicals from the surrounding air. The index of refraction of the polymer changes with the concentration of absorbed chemical( s). The resonator is designed to operate with relatively strong
Mathematical Modeling of Carcinogenesis Based on Chromosome Aberration Data
Xiao-bo Li
2009-01-01
Objective: The progression of human cancer is characterized by the accumulation of genetic instability. An increasing number of experimental genetic molecular techniques have been used to detect chromosome aberrations. Previous studies on chromosome abnormalities often focused on identifying the frequent loci of chromosome alterations, but rarely addressed the issue of interrelationship of chromosomal abnormalities. In the last few years, several mathematical models have been employed to construct models of carcinogenesis, in an attempt to identify the time order and cause-and-effect relationship of chromosome aberrations. The principles and applications of these models are reviewed and compared in this paper. Mathematical modeling of carcinogenesis can contribute to our understanding of the molecular genetics of tumor development, and identification of cancer related genes, thus leading to improved clinical practice of cancer.
A Library of OpenGL-Based Mathematical Image Filters
Von Gagern, Martin; Mercat, Christian
2010-01-01
There are a lot of transformations that can turn one raster image into a derived one in a mathematically interesting way. This article describes a collection of such filters, implemented in OpenGL in order to use the high degree of parallelism modern GPUs provide, thereby providing performance required to process e.g. live camera images in real-time. The filters contained in this library include wallpaper groups, conformal maps described by meromorphic functions, as well as hyperbolic symmetr...
Mathematical model of delay lines based on magnetostatic waves
E. V. Kudinov
2010-12-01
Full Text Available On the example of the delay line have demonstrated the possibility of applying the principle of decomposition to construct mathematical models of microwave devices using magnetostatic waves (MSW in a magnetized epitaxial ferrite films, which allows for a unified methodological basis and the lowest cost to the experimental optimization design of MSW devices for various applications
Mathematical model of delay lines based on magnetostatic waves
E. V. Kudinov
2010-01-01
On the example of the delay line have demonstrated the possibility of applying the principle of decomposition to construct mathematical models of microwave devices using magnetostatic waves (MSW) in a magnetized epitaxial ferrite films, which allows for a unified methodological basis and the lowest cost to the experimental optimization design of MSW devices for various applications
Mathematical Modeling of lndustrial Robots Based on Hamiltonian Mechanics
Záda, V.; Belda, Květoslav
Košice: Slovak Society for Applied Cybernetics and Informatics (SSAKI), 2016, s. 813-818. ISBN 978-1-4673-8606-7. [17th International Carpathian Control Conference (ICCC). Tatranská Lomnica (SK), 29.05.2016-01.06.2016] Institutional support: RVO:67985556 Keywords : Robot -manipulator * Hamiltonian formalism * mathematical modeling * PD control * model-oreinted motion control Subject RIV: BC - Control Systems Theory http://library.utia.cas.cz/separaty/2016/AS/belda-0459855.pdf
Amineborane Based Chemical Hydrogen Storage - Final Report
The development of efficient and safe methods for hydrogen storage is a major hurdle that must be overcome to enable the use of hydrogen as an alternative energy carrier. The objectives of this project in the DOE Center of Excellence in Chemical Hydride Storage were both to develop new methods for on-demand, low temperature hydrogen release from chemical hydrides and to design high-conversion off-board methods for chemical hydride regeneration. Because of their reactive protic (N-H) and hydridic (B-H) hydrogens and high hydrogen contents, amineboranes such as ammonia borane, NH3BH3 (AB), 19.6-wt% H2, and ammonia triborane NH3B3H7 (AT), 17.7-wt% H2, were initially identified by the Center as promising, high-capacity chemical hydrogen storage materials with the potential to store and deliver molecular hydrogen through dehydrogenation and hydrolysis reactions. In collaboration with other Center partners, the Penn project focused both on new methods to induce amineborane H2-release and on new strategies for the regeneration the amineborane spent-fuel materials. The Penn approach to improving amineborane H2-release focused on the use of ionic liquids, base additives and metal catalysts to activate AB dehydrogenation and these studies successfully demonstrated that in ionic liquids the AB induction period that had been observed in the solid-state was eliminated and both the rate and extent of AB H2-release were significantly increased. These results have clearly shown that, while improvements are still necessary, many of these systems have the potential to achieve DOE hydrogen-storage goals. The high extent of their H2-release, the tunability of both their H2 materials weight-percents and release rates, and their product control that is attained by either trapping or suppressing unwanted volatile side products, such as borazine, continue to make AB/ionic-liquid based systems attractive candidates for chemical hydrogen storage applications. These studies also demonstrated
Carbon-Nanotube-Based Chemical Gas Sensor
Kaul, Arunpama B.
2010-01-01
Conventional thermal conductivity gauges (e.g. Pirani gauges) lend themselves to applications such as leak detectors, or in gas chromatographs for identifying various gas species. However, these conventional gauges are physically large, operate at high power, and have a slow response time. A single-walled carbon-nanotube (SWNT)-based chemical sensing gauge relies on differences in thermal conductance of the respective gases surrounding the CNT as it is voltage-biased, as a means for chemical identification. Such a sensor provides benefits of significantly reduced size and compactness, fast response time, low-power operation, and inexpensive manufacturing since it can be batch-fabricated using Si integrated-circuit (IC) process technology.
Mathematical foundation of the optimization-based fluid animation method
Erleben, Kenny; Misztal, Marek Krzysztof; Bærentzen, Jakob Andreas
2011-01-01
We present the mathematical foundation of a fluid animation method for unstructured meshes. Key contributions not previously treated are the extension to include diffusion forces and higher order terms of non-linear force approximations. In our discretization we apply a fractional step method to be...... stress tensor. Rather than applying a straightforward temporal finite difference method followed by a projection method to enforce incompressibility as done in the stable fluids method, the last step of the fractional step method is rewritten as an optimization problem to make it easy to incorporate non...
Hsu, Chun-Wei; Goh, Joshua O. S.
2016-01-01
When comparing between the values of different choices, human beings can rely on either more cognitive processes, such as using mathematical computation, or more affective processes, such as using emotion. However, the neural correlates of how these two types of processes operate during value-based decision-making remain unclear. In this study, we investigated the extent to which neural regions engaged during value-based decision-making overlap with those engaged during mathematical and emotional processing in a within-subject manner. In a functional magnetic resonance imaging experiment, participants viewed stimuli that always consisted of numbers and emotional faces that depicted two choices. Across tasks, participants decided between the two choices based on the expected value of the numbers, a mathematical result of the numbers, or the emotional face stimuli. We found that all three tasks commonly involved various cortical areas including frontal, parietal, motor, somatosensory, and visual regions. Critically, the mathematical task shared common areas with the value but not emotion task in bilateral striatum. Although the emotion task overlapped with the value task in parietal, motor, and sensory areas, the mathematical task also evoked responses in other areas within these same cortical structures. Minimal areas were uniquely engaged for the value task apart from the other two tasks. The emotion task elicited a more expansive area of neural activity whereas value and mathematical task responses were in more focal regions. Whole-brain spatial correlation analysis showed that valuative processing engaged functional brain responses more similarly to mathematical processing than emotional processing. While decisions on expected value entail both mathematical and emotional processing regions, mathematical processes have a more prominent contribution particularly in subcortical processes. PMID:27375466
Hsu, Chun-Wei; Goh, Joshua O S
2016-01-01
When comparing between the values of different choices, human beings can rely on either more cognitive processes, such as using mathematical computation, or more affective processes, such as using emotion. However, the neural correlates of how these two types of processes operate during value-based decision-making remain unclear. In this study, we investigated the extent to which neural regions engaged during value-based decision-making overlap with those engaged during mathematical and emotional processing in a within-subject manner. In a functional magnetic resonance imaging experiment, participants viewed stimuli that always consisted of numbers and emotional faces that depicted two choices. Across tasks, participants decided between the two choices based on the expected value of the numbers, a mathematical result of the numbers, or the emotional face stimuli. We found that all three tasks commonly involved various cortical areas including frontal, parietal, motor, somatosensory, and visual regions. Critically, the mathematical task shared common areas with the value but not emotion task in bilateral striatum. Although the emotion task overlapped with the value task in parietal, motor, and sensory areas, the mathematical task also evoked responses in other areas within these same cortical structures. Minimal areas were uniquely engaged for the value task apart from the other two tasks. The emotion task elicited a more expansive area of neural activity whereas value and mathematical task responses were in more focal regions. Whole-brain spatial correlation analysis showed that valuative processing engaged functional brain responses more similarly to mathematical processing than emotional processing. While decisions on expected value entail both mathematical and emotional processing regions, mathematical processes have a more prominent contribution particularly in subcortical processes. PMID:27375466
Mathematics achievement based on gender among eight grade school students in Jordan
Rabab'h, Belal Sadiq Hamed; Veloo, Arsaythamby; Perumal, Selvan
2015-05-01
The purpose of this study is to identify the differences in gender base on numbers, algebra, geometry and mathematics achievement among Jordanian 8th grade school students. The respondent of this study were 337 students from eight public secondary schools in Alkoura district and selected by using stratified random sampling. The study comprised of 179 (53%) males and 158 (47%) females students. The mathematics test comprises of 30 items which has eight items for numbers, 14 items for algebra and eight items for geometry. Finding from independent sample t-test shows that female student score higher than male students in numbers, algebra, mathematics achievement and spatial visualization. There is no significant difference in geometry base for gender. This study also indicates that numbers, algebra and mathematics achievement favorable to female and bias to male students. The main recommendations from this study are for teachers and other educational professionals to focus on the numbers and algebra for male students to improve the learning of mathematics, and feeding program through benefiting from tutorial classes to avoid of weakness in different aspects of mathematics achievement. Gender differences in mathematics in secondary school students in Jordan continue to exist and these differences may influence future educational and occupational pathways.
DiffGame: Game-based mathematics learning for physics
Pedersen, Mads Kock; Dohn, Niels Bonderup; Lieberoth, Andreas; Sherson, Jacob
2016-01-01
Differentiation is a mathematical skill applied throughout science in order to describe the change of a function with respect to a dependent variable. Thus, an intuitive understanding of differentiation is necessary to work with the mathematical frameworks used to describe physical systems in the higher levels of education. In order to obtain this intuition repeated practice is required. In this paper we present the development of DiffGame, which consists of a series of exercises that introduce the basic principles of differentiation for high-school students through game-like elements. DiffGame have been tested with 117 first-year students from a single Danish high school, who did not have any prior training in differentiation. The students' learning was assessed by the data obtained directly from DiffGame. The test demonstrated the efficacy of DiffGame, since students at all levels demonstrate a learning gain. In contrast to previous studies demonstrating most learning in the lower tier of students, we find ...
Analytical derivation: An epistemic game for solving mathematically based physics problems
Bajracharya, Rabindra R.; Thompson, John R.
2016-06-01
Problem solving, which often involves multiple steps, is an integral part of physics learning and teaching. Using the perspective of the epistemic game, we documented a specific game that is commonly pursued by students while solving mathematically based physics problems: the analytical derivation game. This game involves deriving an equation through symbolic manipulations and routine mathematical operations, usually without any physical interpretation of the processes. This game often creates cognitive obstacles in students, preventing them from using alternative resources or better approaches during problem solving. We conducted hour-long, semi-structured, individual interviews with fourteen introductory physics students. Students were asked to solve four "pseudophysics" problems containing algebraic and graphical representations. The problems required the application of the fundamental theorem of calculus (FTC), which is one of the most frequently used mathematical concepts in physics problem solving. We show that the analytical derivation game is necessary, but not sufficient, to solve mathematically based physics problems, specifically those involving graphical representations.
A framework for designing a research-based "mathematics counsellor" teacher programme
Niss, Mogens Allan; Thomas Jankvist, Uffe
2015-01-01
This article addresses one way in which decades of mathematics education research results can inform practice, by offering a framework for designing and implementing an in-service teacher education programme for upper secondary mathematics teachers in Denmark. The programme aims to educate a “task...... force” of so-called “maths counsellors”, i.e., mathematics teachers whose goal it is to help identify students with genuine learning difficulties in mathematics, investigate the nature of these difficulties, and carry out research-based interventions to assist the students in overcoming them. We present...... and discuss the various components of the programme, theoretical as well as practical, and account for how these make up a framework for designing a research-based “maths counsellor” teacher programme...
Math Play : growing and developing mathematics understanding in an emergent play-based environment
DeGroot, Kendra
2012-01-01
This project explores how mathematics growth and development can be supported, documented and assessed in an emergent play-based early childhood education environment inspired by the practices and principles of Reggio Emilia. Using the California Preschool Learning Foundations as a framework, Math Play includes developmentally appropriate activities and environments that support cognitive development within the mathematics domain. This curriculum documents how a classroom's emergent themes we...
无
2001-01-01
On the basis of analysis on the temperature monitoring methods for high voltage devices, a new type of fiber optic sensor structure with reference channel is given. And the operation principle of fiber optic sensor is analysed at large based on the absorption of semiconductor chip. The mathematical model of both devices and the whole system are also given. It is proved by the experiment that this mathematical model is reliable.
Chemical Sensors Based on Metal Oxide Nanostructures
Hunter, Gary W.; Xu, Jennifer C.; Evans, Laura J.; VanderWal, Randy L.; Berger, Gordon M.; Kulis, Mike J.; Liu, Chung-Chiun
2006-01-01
This paper is an overview of sensor development based on metal oxide nanostructures. While nanostructures such as nanorods show significan t potential as enabling materials for chemical sensors, a number of s ignificant technical challenges remain. The major issues addressed in this work revolve around the ability to make workable sensors. This paper discusses efforts to address three technical barriers related t o the application of nanostructures into sensor systems: 1) Improving contact of the nanostructured materials with electrodes in a microse nsor structure; 2) Controling nanostructure crystallinity to allow co ntrol of the detection mechanism; and 3) Widening the range of gases that can be detected by using different nanostructured materials. It is concluded that while this work demonstrates useful tools for furt her development, these are just the beginning steps towards realizati on of repeatable, controlled sensor systems using oxide based nanostr uctures.
Opportunity-to-Learn Context-Based Tasks Provided by Mathematics Textbooks
Wijaya, Ariyadi; van den Heuvel-Panhuizen, Marja; Doorman, Michiel
2015-01-01
Based on the findings of an error analysis revealing that Indonesian ninth- and tenth-graders had difficulties in solving context-based tasks, we investigated the opportunity-to-learn offered by Indonesian textbooks for solving context-based mathematics tasks and the relation of this opportunity-to-learn to students' difficulties in solving these…
Johann Engelbrecht
2009-09-01
Full Text Available Following the political changes of 1994 in South Africa, the decision was taken to replace the traditional skills-based education system at primary and secondary school level (Grades 1 - 12 with an outcomes-based education system (OBE. The OBE approach, referred to as Curriculum 2005, was introduced into schools in 1998. The implementation of the OBE system did not occur without problems, giving rise to revised initiatives and a fair amount of criticism. The 2009 intake of students at universities is the ﬁrst group of students that had been subjected to the OBE approach for their entire school career. This is also the ﬁrst group of students for whom some form of mathematics was compulsory up to Grade 12 level in the form of mathematics or mathematical literacy. These students were characterised by the fact that their mathematics marks for Grade 12 were exceptionally high and that many more students qualiﬁed for university entrance. This article reports on the impact of this new education system on the mathematics prepared-ness of students entering university. The study involves an empirical analysis of the students in the ﬁrst-year mathematics course for engineering students at the University of Pretoria as well as an analysis of a questionnaire completed by experienced lecturers at this university. The question addressed in this article is how the 2009 intake of students cope with mathematics at university level with regard to Performance General attributes Mathematical attributes Content-related attributesResults indicate a decrease in mathematics performance of these students at university level and that the inﬂated matric marks result in unjustiﬁed expectations. However, it is not unusual for marks to decrease from school to university and there is still too little evidence for serious concern. The study also indicates that these students seem to be better equipped with regard to personal attributes such as self-conﬁdence and
Layout-based substitution tree indexing and retrieval for mathematical expressions
Schellenberg, Thomas; Yuan, Bo; Zanibbi, Richard
2012-01-01
We introduce a new system for layout-based (LATEX) indexing and retrieval of mathematical expressions using substitution trees. Substitution trees can efficiently store and find expressions based on the similarity of their symbols, symbol layout, sub-expressions and size. We describe our novel implementation and some of our modifications to the substitution tree indexing and retrieval algorithms. We provide an experiment testing our system against the TF-IDF keyword-based system of Zanibbi and Yuan and demonstrate that, in many cases, the quality of search results returned by both systems is comparable (overall means, substitution tree vs. keywordbased: 100% vs. 89% for top 1; 48% vs. 51% for top 5; 22% vs. 28% for top 20). Overall, we present a promising first attempt at layout-based substitution tree indexing and retrieval for mathematical expressions and believe that this method will prove beneficial to the field of mathematical information retrieval.
Mathematical thinking of maintenance. Problem setting and solving bases
Plant or mechanical facility for maintenance became more complicated than before and consisted of many subsystems made of various equipments or facilities with parts, which were a system having complicated and hierarchical structure. Maintenance was required to be properly implemented to assure reliability of a system for a long period so as for each equipment to play a specified role for a stable operation of plant. Mathematical thinking using probability theory was rational to optimize maintenance action with failure rate function of system or part of equipment. Reliability function, maintainability function and availability of plant and equipment were defined. Unreliability function was called failure time distribution function (F(t)) and failure rate function (λ(t)) was defined as the ratio of failure time density distribution function (dF(t)/dt) to reliability function (1-F(t)). λ(t) could be expressed as a simple equation with Weibull parameter. Availability at steady state was attributed to ratio of average operating time to sum of operating time and maintenance time, i.e. MTBF/(MTBF+MTTR) where MTBF was mean time between failures and MTTR was mean time to repair. Optimization of system risk and maintenance action was encouraged using computational science simulating material degradation. (T. Tanaka)
Alexander B. Bakulev
2012-11-01
Full Text Available This article deals with mathematical models and algorithms, providing mobility of sequential programs parallel representation on the high-level language, presents formal model of operation environment processes management, based on the proposed model of programs parallel representation, presenting computation process on the base of multi-core processors.
Alexander B. Bakulev; Marina A. Bakuleva; Svetlana B. Avilkina
2012-01-01
This article deals with mathematical models and algorithms, providing mobility of sequential programs parallel representation on the high-level language, presents formal model of operation environment processes management, based on the proposed model of programs parallel representation, presenting computation process on the base of multi-core processors.
Discourses about School-Based Mathematics Teacher Education in Finland and Sweden
Ryve, Andreas; Hemmi, Kirsti; Borjesson, Mats
2013-01-01
In this cross-case study we focus on school-based teacher education in Sweden and Finland. Through the use of focus-group interviews with mathematics teacher educators in Finland and Sweden, the study shows that there are substantial differences in how school-based teacher education is introduced and portrayed in the discourse about teacher…
Data base of chemical explosions in Kazakhstan
Demin, V.N. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan); Malahova, M.N. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan); Martysevich, P.N. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan); Mihaylova, N.N. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan); Nurmagambetov, A. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan); Kopnichev, Yu.F. D. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan); Edomin, V.I. [National Nuclear Center of Republic of Kazakhstan Institute of Geophysical Researches (Kazakhstan)
1996-12-01
Within the bounds of this report, the following works were done: (1) Information about explosion quarries, located in Southern, Eastern and Northern Kasakstan was summarized. (2) The general information about seismicity of areas of location of explosion quarries was adduced. (3) The system of observation and seismic apparatus, recording the local earthquakes and quarry explosions at the territory of Kazakstan were described. (4) Data base of quarry explosions, that were carried out in Southern, Eastern and Northern Kazakstan during 1995 and first half of 1996 year was adduced. (5) Upon the data of registration of explosions in Southern Kazakstan the correlative dependences between power class of explosions and summary weight of charge were constructed. (6) Seismic records of quarry explosions were adduced. It is necessary to note, that the collection of data about quarry explosions in Kazakstan in present time is very difficult task. Organizations, that makes these explosions, are always suffering reorganizations and sometimes it is actually impossible to receive all the necessary information. Some quarries are situated in remote, almost inaccessible regions, and within the bounds of supplier financing not the every quarry was in success to visit. So the present data base upon the chemical explosions for 1995 is not full and in further it`s expansion is possible.
Rees, Stephen Edward; Rychwicka-Kielek, Beate A; Andersen, Bjarne F;
2012-01-01
Abstract Background: Repeated arterial puncture is painful. A mathematical method exists for transforming peripheral venous pH, PCO2 and PO2 to arterial eliminating the need for arterial sampling. This study evaluates this method to monitor acid-base and oxygenation during admission for exacerbat......Abstract Background: Repeated arterial puncture is painful. A mathematical method exists for transforming peripheral venous pH, PCO2 and PO2 to arterial eliminating the need for arterial sampling. This study evaluates this method to monitor acid-base and oxygenation during admission...
der Schaft, Arjan van; Rao, Shodhan; Jayawardhana, Bayu
2011-01-01
Motivated by recent progress on the interplay between graph theory, dynamics, and systems theory, we revisit the analysis of chemical reaction networks described by mass action kinetics. For reaction networks possessing a thermodynamic equilibrium we derive a compact formulation exhibiting at the same time the structure of the complex graph and the stoichiometry of the network, and which admits a direct thermodynamical interpretation. This formulation allows us to easily characterize the set ...
Mathematical design of prokaryotic clone-based microarrays
Pieterse, B.; Quirijns, E.J.; Schuren, F.H.J.; Werf, M.J. van der
2005-01-01
Background: Clone-based microarrays, on which each spot represents a random genomic fragment, are a good alternative to open reading frame-based microarrays, especially for microorganisms for which the complete genome sequence is not available. Since the generation of a genomic DNA library is a rand
Reviandari Widyatiningtyas
2015-07-01
Full Text Available The study was report the findings of an only post-test control group research design and aims to analyze the influence of problem-based learning approach, school level, and students’ prior mathematical ability to student’s mathematics critical thinking ability. The research subjects were 140 grade ten senior high school students coming from excellent and moderate school level. The research instruments a set of mathematical critical thinking ability test, and the data were analyzed by using two ways ANOVA and t-test. The research found that the problem based learning approach has significant impact to the ability of students’ mathematics critical thinking in terms of school level and students’ prior mathematical abilities. Furthermore. This research also found that there is no interaction between learning approach and school level, and learning approach and students’ prior mathematics ability to students’ mathematics critical thinking ability.
Mathematical Modelling of a Hybrid Micro-Cogeneration Group Based on a Four Stroke Diesel Engine
Apostol Valentin
2014-06-01
Full Text Available The paper presents a part of the work conducted in the first stage of a Research Grant called ”Hybrid micro-cogeneration group of high efficiency equipped with an electronically assisted ORC” acronym GRUCOHYB. The hybrid micro-cogeneration group is equipped with a four stroke Diesel engine having a maximum power of 40 kW. A mathematical model of the internal combustion engine is presented. The mathematical model is developed based on the Laws of Thermodynamics and takes into account the real, irreversible processes. Based on the mathematical model a computation program was developed. The results obtained were compared with those provided by the Diesel engine manufacturer. Results show a very high correlation between the manufacturer’s data and the simulation results for an engine running at 100% load. Future developments could involve using an exergetic analysis to show the ability of the ORC to generate electricity from recovered heat
Applying Mathematical Optimization Methods to an ACT-R Instance-Based Learning Model
Said, Nadia; Engelhart, Michael; Kirches, Christian; Körkel, Stefan; Holt, Daniel V.
2016-01-01
Computational models of cognition provide an interface to connect advanced mathematical tools and methods to empirically supported theories of behavior in psychology, cognitive science, and neuroscience. In this article, we consider a computational model of instance-based learning, implemented in the ACT-R cognitive architecture. We propose an approach for obtaining mathematical reformulations of such cognitive models that improve their computational tractability. For the well-established Sugar Factory dynamic decision making task, we conduct a simulation study to analyze central model parameters. We show how mathematical optimization techniques can be applied to efficiently identify optimal parameter values with respect to different optimization goals. Beyond these methodological contributions, our analysis reveals the sensitivity of this particular task with respect to initial settings and yields new insights into how average human performance deviates from potential optimal performance. We conclude by discussing possible extensions of our approach as well as future steps towards applying more powerful derivative-based optimization methods. PMID:27387139
Chemical sensors based on the modification of a resonator cavity
Hennig, Oliver; Mendes, Sergio B.; Fallahi, Mahmoud; Peyghambarian, Nasser
1999-02-01
In this paper, we present a chemical sensor based on the modification of an optical resonator: the optical path length of the resonant cavity is changed by the chemical in question, thus shifting its resonant frequency.
Developing Teaching Materials PISA-Based for Mathematics and Science of Junior High School
Somakim; Suharman, Andi; Madang, Kodri; Taufiq
2016-01-01
This research aims to develop valid and practical teaching materials for mathematics and science lesson PISA-based for junior high school students and to determine potential effects on students in scientific activity. Subjects of this study were students of Junior High School 9 Palembang (SMP Negeri 9 Palembang). The method used in this study is…
Hongli Liu; Xiong Zhou; Lei Xiao
2012-01-01
Adopting the microscopic observation imaging and digital image processing technologies, this paper researches a new measuring method of indoor inhalable particulate matter concentration and size distribution .It realizes denoising, binarization, filtering and edge detection to based on mathematical morphology, regional filled and calibration detection to particulate matter image, designs the parameters recognition algorithm for particulate matter size, fractal dimension ,shape factors and so ...
Modeling Zombie Outbreaks: A Problem-Based Approach to Improving Mathematics One Brain at a Time
Lewis, Matthew; Powell, James A.
2016-01-01
A great deal of educational literature has focused on problem-based learning (PBL) in mathematics at the primary and secondary level, but arguably there is an even greater need for PBL in college math courses. We present a project centered around the Humans versus Zombies moderated tag game played on the Utah State University campus. We discuss…
Analytical Derivation: An Epistemic Game for Solving Mathematically Based Physics Problems
Bajracharya, Rabindra R.; Thompson, John R.
2016-01-01
Problem solving, which often involves multiple steps, is an integral part of physics learning and teaching. Using the perspective of the epistemic game, we documented a specific game that is commonly pursued by students while solving mathematically based physics problems: the "analytical derivation" game. This game involves deriving an…
Assessing Long-Term Effects of Inquiry-Based Learning: A Case Study from College Mathematics
Kogan, Marina; Laursen, Sandra L.
2014-01-01
As student-centered approaches to teaching and learning are more widely applied, researchers must assess the outcomes of these interventions across a range of courses and institutions. As an example of such assessment, this study examined the impact of inquiry-based learning (IBL) in college mathematics on undergraduates' subsequent grades…
Incikabi, Lutfi; Sancar Tokmak, Hatice
2012-01-01
This case study examined the educational software evaluation processes of pre-service teachers who attended either expertise-based training (XBT) or traditional training in conjunction with a Software-Evaluation checklist. Forty-three mathematics teacher candidates and three experts participated in the study. All participants evaluated educational…
Petersen, Richard H.
1997-01-01
The objectives of the Institute were: (a) increase participants' content knowledge about aeronautics, science, mathematics, and technology, (b) model and promote the use of scientific inquiry through problem-based learning, (c) investigate the use of instructional technologies and their applications to curricula, and (d) encourage the dissemination of TEI experiences to colleagues, students, and parents.
Mathematics Achievement with Digital Game-Based Learning in High School Algebra 1 Classes
Ferguson, Terri Lynn Kurley
2014-01-01
This study examined the impact of digital game-based learning (DGBL) on mathematics achievement in a rural high school setting in North Carolina. A causal comparative research design was used in this study to collect data to determine the effectiveness of DGBL in high school Algebra 1 classes. Data were collected from the North Carolina…
Exploring the Impact of Web-Based Learning Tools in Middle School Mathematics and Science Classrooms
Kay, Robin
2011-01-01
This study examines the impact of Web-Based Learning Tools (WBLTs), also known as learning objects, in middle school mathematics and science classrooms. Survey, qualitative, and student performance data were collected from a sample of 18 teachers and 443 students. Teachers were very positive about the learning benefits, quality of WBLTs, and…
Effects of Computer-Based Visual Representation on Mathematics Learning and Cognitive Load
Yung, Hsin I.; Paas, Fred
2015-01-01
Visual representation has been recognized as a powerful learning tool in many learning domains. Based on the assumption that visual representations can support deeper understanding, we examined the effects of visual representations on learning performance and cognitive load in the domain of mathematics. An experimental condition with visual…
Using GIS to Teach Place-Based Mathematics in Rural Classrooms
Leonard, Jacqueline; Russell, Nicole M.; Hobbs, Robert M.; Buchanan, Heather
2013-01-01
The purpose of this article is to promote the use of GIS and place-based education (PBE) in rural mathematics classrooms. The pedagogy of place is disappearing from rural communities because of declining enrollments, lack of support, and federal mandates to focus more on basic academic skills. However, PBE does not stand in opposition to…
An Analysis of the Competency-Based Secondary Mathematics Curriculum in Sri Lanka
Egodawatte, Gunawardena
2014-01-01
In education, there is a growing interest in the concept of "competency" especially in vocational training and professional development. The concept is strongly associated with the ability to apply knowledge and skills in effective ways in unanticipated situations. In Sri Lanka, a new competency-based mathematics curriculum was…
Number-free Mathematics Based on T-norm Fuzzy Logic
Běhounek, Libor
Granada: EUSFLAT, 2009 - (Carvalho, J.; Dubois, D.; Kaymak, U.; Sousa, J.), s. 449-454 ISBN 978-989-95079-6-8. [IFSA - EUSFLAT 2009. International Fuzzy Systems Association World Congress 2009, European Society for Fuzzy Logic and Technology Conference 2009. Lisabon (PT), 20.07.2009-24.07.2009] R&D Projects: GA AV ČR IAA100300503 Institutional research plan: CEZ:AV0Z10300504 Keywords : Fuzzy Class Theory * fuzzy mathematics * fuzzy set * real -valued function * similarity-based limit * t-norm fuzzy logic Subject RIV: BA - General Mathematics
Gultepe, Nejla; Yalcin Celik, Ayse; Kilic, Ziya
2013-01-01
The purpose of the study was to examine the effects of students' conceptual understanding of chemical concepts and mathematical processing skills on algorithmic problem-solving skills. The sample (N = 554) included grades 9, 10, and 11 students in Turkey. Data were collected using the instrument "MPC Test" and with interviews. The…
A method of building information extraction based on mathematical morphology and multiscale
Li, Jing-wen; Wang, Ke; Zhang, Zi-ping; Xue, Long-li; Yin, Shou-qiang; Zhou, Song
2015-12-01
In view of monitoring the changes of buildings on Earth's surface ,by analyzing the distribution characteristics of building in remote sensing image, combined with multi-scale in image segmentation and the advantages of mathematical morphology, this paper proposes a multi-scale combined with mathematical morphology of high resolution remote sensing image segmentation method, and uses the multiple fuzzy classification method and the shadow of auxiliary method to extract information building, With the comparison of k-means classification, and the traditional maximum likelihood classification method, the results of experiment object based on multi-scale combined with mathematical morphology of image segmentation and extraction method, can accurately extract the structure of the information is more clear classification data, provide the basis for the intelligent monitoring of earth data and theoretical support.
Chamberlin, Michelle T.
2013-01-01
In a mathematics course for prospective elementary teachers, we strove to model standards-based pedagogy. However, an end-of-class reflection revealed the prospective teachers were considering incorporating standards-based strategies in their future classrooms in ways different from our intent. Thus, we drew upon the framework presented by Simon,…
Polymers based on chemically modified starch
Horák, Pavel; Kruliš, Zdeněk; Šárka, E.; Kobera, Libor
Prague : Czech Chemical Society, 2014 - (Řápková, R.; Čopíková, J.; Šárka, E.), s. 88-90 ISBN 978-80-86238-70-8. [International Conference on Polysaccharides-Glycoscience /10./. Prague (CZ), 22.10.2014-24.10.2014] R&D Projects: GA TA ČR(CZ) TA04020853 Institutional support: RVO:61389013 Keywords : starch * chemical modification * degree of substitution Subject RIV: CD - Macromolecular Chemistry
Xianjun Li; Yongfeng Luo; Hongbin Chen; Xia He; Jianxiong Lv; Yiqiang Wu
2013-01-01
High intensive microwave pretreatment is a new method to modify wood for the fabrication of wood-based nanocomposites. Based on the physical law on heat transfer, a mathematical model to describe the temperature profiles within wood heated by high intensive microwave was established and simulated in this research. The results showed that the temperature profiles within wood were related to microwave heating methods; The temperature inside wood firstly increased and then gradually decreased al...
M. N. Modebelu
2014-04-01
Full Text Available This study aimed at determining the effect of reform-based-instructional method learning styles on students’ achievement and retention in mathematics. A sample size of 119 students was randomly selected. The quasi-experimental design comprising pre-test, post-test, and randomized control group were employed. The Collin Rose learning styles identification and Mathematics instrument were used for data collection. Data collected were analyzed using mean, standard deviation and analysis of covariance. Results revealed that students taught Mathematics with reform-based instructional method performed better than students taught the same mathematics content with the traditional method. Also, students' achievement in mathematics was influenced by the students' leaning styles. For effective teaching and learning in Mathematics, there should be reforms in the instructional processes, taking into consideration the influence of the students' learning styles in particular.
A pilot home-based early intervention study to improve the mathematical skills of young children
Ayşegül Şükran Öz
2013-12-01
Full Text Available Children who come from low socioeconomic backgrounds and children with learning disabilities are found to be at risk for future failure in mathematics. Even though the mathematics scores increases over time the achievement gap remains between the various ethnic and socioeconomic groups. One way to prevent this failure is to identify the students who are at risk and provide them with effective early intervention. This study reports the results of a pilot early mathematics intervention study focusing on two Turkish families in the US. In this single-subject research, a multiple probe technique was used in order to examine the impact of the SRA DLM Math Pre-K CD-ROM in combination with parent scaffolding on young children’s number sense skills. Two parent-child dyads participated in this study. Two semi-structured interviews were conducted with the parents before and after the intervention. The child participants received 3 Mathematical Curriculum Based Measure (CBM every week to monitor their progress. Building Blocks Assessment was used to identify whether children were able to generalize the number sense skills developed during work sessions in different settings. This measure was administered both before and after the intervention.This study demonstrated that children’s and parents’ use of a software program where they work collaboratively at home resulted in increased number sense skills. These results were interpreted in the context of socio-cultural theory. The parents displayed different strategies during the mathematics work sessions, reflecting their own feelings about mathematics and technology.
PENGEMBANGAN WEB-BASED MATHEMATICS LEARNING SISWA KELAS V SDN KOTAGEDE 3 YOGYAKARTA
Titin Mulyaningsih
2015-07-01
Full Text Available Penelitian ini bertujuan untuk menghasilkan web-based mathematics learning yang layak untuk siswa kelas V di SD Kotagede 3 Yogyakarta. Disamping itu web-based mathematics learning yang dikembangkan dalam rangka menciptakan pembelajaran yang menyenangkan. Penelitian ini merupakan penelitian dan pengembangan yang terdiri dari 10 langkah kegiatan. Subjek penelitian ini adalah 32 siswa yang terdiri dari tiga siswa uji coba perorangan, 9 siswa uji coba kelompok kecil, dan 20 siswa uji coba lapangan. Instrumen yang digunakan dalam pengumpulan data adalah lembar validasi untuk ahli materi, ahli media dan angket tanggapan untuk siswa. Analisis data menggunakan analisis statistik deskripstif. Hasil validasi ahli materi menunjukkan skor rata-rata 80 yang termasuk kriteria sangat baik. Sedangkan hasil validasi ahli media menunjukkan skor rata-rata 70 termasuk dalam kriteria baik. Tanggapan siswa terhadap produk yang dikembangkan termasuk baik yaitu dengan perolehan skor rata-rata 17,9 atau sebesar 89,5% siswa menyatakan bahwa produk pengembangan ini layak untuk digunakan sebagai sumber belajar yang menyenangkan. Kata kunci: web-based learning, pembelajaran matematika DEVELOPING WEB-BASED MATHEMATICS LEARNING FOR THE FIFTH GRADE OF ELEMENTARY SCHOOL KOTAGEDE 3, YOGYAKARTA Abstract This study aims to produce a web-based mathematics learning viable for fifth grade students in elementary Kotagede 3 Yogyakarta. Besides, web-based learning mathematics developed in order to create a fun learning. This study is a research and development activities consist of 10 steps. The subjects were 32 students consisting of three students individual trials, nine trials a small group of students, and 20 students field trials. The instruments used in data collection is for the expert validation sheet material, media experts and questionnaire responses for the students. Analyzed using descriptive statistics. Matter expert validation results showed an average score of 80 which
Reviandari Widyatiningtyas; Yaya S. Kusumah; Utari Sumarmo; Jozua Sabandar
2015-01-01
The study was report the findings of an only post-test control group research design and aims to analyze the influence of problem-based learning approach, school level, and students’ prior mathematical ability to student’s mathematics critical thinking ability. The research subjects were 140 grade ten senior high school students coming from excellent and moderate school level. The research instruments a set of mathematical critical thinking ability test, and the data were analyzed by us...
Revilla, Marta; Galán, Berta; Viguri, Javier R
2016-07-01
An integrated mathematical model is proposed for modelling a moving bed biofilm reactor (MBBR) for removal of chemical oxygen demand (COD) under aerobic conditions. The composite model combines the following: (i) a one-dimensional biofilm model, (ii) a bulk liquid model, and (iii) biological processes in the bulk liquid and biofilm considering the interactions among autotrophic, heterotrophic and predator microorganisms. Depending on the values for the soluble biodegradable COD loading rate (SCLR), the model takes into account a) the hydrolysis of slowly biodegradable compounds in the bulk liquid, and b) the growth of predator microorganisms in the bulk liquid and in the biofilm. The integration of the model and the SCLR allows a general description of the behaviour of COD removal by the MBBR under various conditions. The model is applied for two in-series MBBR wastewater plant from an integrated cellulose and viscose production and accurately describes the experimental concentrations of COD, total suspended solids (TSS), nitrogen and phosphorous obtained during 14 months working at different SCLRs and nutrient dosages. The representation of the microorganism group distribution in the biofilm and in the bulk liquid allow for verification of the presence of predator microorganisms in the second reactor under some operational conditions. PMID:27085154
Development of GaN-based micro chemical sensor nodes
Son, Kyung-ah; Prokopuk, Nicholas; George, Thomas; Moon, Jeong S.
2005-01-01
Sensors based on III-N technology are gaining significant interest due to their potential for monolithic integration of RF transceivers and light sources and the capability of high temperature operations. We are developing a GaN-based micro chemical sensor node for remote detection of chemical toxins, and present electrical responses of AlGaN/GaN HEMT (High Electron Mobility Transistor) sensors to chemical toxins as well as other common gases.
Using Inquiry-Based Learning to Support the Mathematical Learning of Students with SEBD
Jonathan Camenzuli
2014-11-01
Full Text Available This paper, which draws on action research methodology, explores the use of inquirybased learning (IBL in the teaching of mathematics to students with social, emotional and behavioural difficulties (SEBD. The year-long study was conducted in a Form 3 secondary class that grouped 13 male students with SEBD in a Maltese secondary school. After first creating an IBL-friendly classroom environment in the initial months, the actual implementation of IBL pedagogy in class began in the second term and spread over a 15 week period. The data included teacher observations that were recorded in a reflective research journal, two sessions of in-depth interviews with students, student journal writing, samples of students’ work and student marks in the school-based half yearly and annual mathematics examinations. The findings indicate that the use of IBL in the mathematics classroom can benefit students with SEBD in a number of ways. These include infusing a sense of enjoyment during lessons, improved student behaviour and motivation to learn, and facilitating the learning of mathematics which generally translated in higher achievement levels.
Polymer based on chemically modified starch
Horák, Pavel; Kruliš, Zdeněk; Šárka, E.; Kobera, Libor
Praha : Ústav makromolekulární chemie AV ČR, v. v. i, 2014. s. 82. ISBN 978-80-85009-81-1. [Česko-slovenská konference POLYMERY 2014 /8./. 06.10.2014-09.10.2014, Třešť] R&D Projects: GA TA ČR(CZ) TA04020853 Institutional support: RVO:61389013 Keywords : starch * chemical modification * degree of substitution Subject RIV: CD - Macromolecular Chemistry
Adaptive Segmentation Method for 2-D Barcode Image Base on Mathematic Morphological
Jianhua Li
2013-10-01
Full Text Available Segmentation is a key process of 2-D barcode identification. In this study we propose a fast adaptive segmentation method that is based on morphological method which is suitable for kinds of 2-D barcode images with different scale, angle and sort. The algorithm is based on mathematical morphology, the basic idea of the algorithm is to use Multi-scale open reconstruction of mathematical morphology to transform the image continuously, then choose whether to terminate by the results of the adjacent image transformation and finally get the final segmentation results by further processing of the images obtain from termination.The proposed approach is applied in experiments on 2-D barcodes with complicated background. The results indicated that the proposed method is very effective in adaptively 2-D barcode image segmentation.
Volodymyr Valentynovych Tkach
2012-07-01
Full Text Available The electroanalytic process of the detection of biosubstances, realized by the biosensor, based in conducting polyheterocyclic compounds, the function of which contained autocatalytic stage, was mathematically described. The correspondent mathematical model was analyzed by linear stability theory and bifurcational analysis. The electrochemical instabilities, capable to succeed in this process, were explained in the terms of this model.
Lin, Cheng-Yao
2008-01-01
This study explored the efficacy of web-based instruction in topics in elementary school mathematics in fostering teachers' confidence and competence in using instructional technology, and thereby promoting more positive attitudes toward using computers and Internet resources in the mathematics classroom. The results indicated that students who…
Widyatiningtyas, Reviandari; Kusumah, Yaya S.; Sumarmo, Utari; Sabandar, Jozua
2015-01-01
The study reported the findings of an only post-test control group research design and aims to analyze the influence of problem-based learning approach, school level, and students' prior mathematical ability to student's mathematics critical thinking ability. The research subjects were 140 grade ten senior high school students coming from…
Palla, Mirko; Bosco, Filippo Giacomo; Yang, Jaeyoung; Rindzevicius, Tomas; Alstrøm, Tommy Sonne; Schmidt, Michael Stenbak; Lin, Qiao; Ju, Jingyue; Boisen, Anja
This paper presents the development of a novel statistical method for quantifying trace amounts of biomolecules by surface-enhanced Raman spectroscopy (SERS) using a rigorous, single molecule (SM) theory based mathematical derivation. Our quantification framework could be generalized for planar...... SERS substrates, in which the nanostructured features can be approximated as a closely spaced electromagnetic dimer problem. The potential for SM detection was also shown, which opens up an exciting opportunity in the field of SERS quantification....
How primary school teachers posed problems for inquiry based mathematics education
Hošpesová, A.; Samková, L.; Tichá, Marie; Roubíček, Filip
Prague: Charles University, Faculty of Education, 2015 - (Novotná, J.; Moraová, H.), s. 156-165 ISBN 978-80-7290-833-2. [SEMT'15 - International Symposium, Elementary Maths Teaching. Praha (CZ), 16.08.2015-21.08.2015] R&D Projects: GA ČR(CZ) GA14-01417S Institutional support: RVO:67985840 Keywords : inquiry based mathematics education * posing problems * primary school teacher training * pre-service and in-service teachers Subject RIV: AM - Education
Genevieve Lachance; Jean Ruel
2010-01-01
This paper presents an experimental study of three bioreactor configurations. The bioreactor is intended to be used for the development of tissue-engineered heart valve substitutes. Therefore it must be able to reproduce physiological flow and pressure waveforms accurately. A detailed analysis of three bioreactor arrangements is presented using mathematical models based on the windkessel (WK) approach. First, a review of the many applications of this approach in medical studies enhances its f...
Scenario Analysis of Web Service Composition based on Multi-Criteria Mathematical Goal Programming
LiYing Cui; Soundar Kumara; Dongwon Lee
2011-01-01
This paper addresses the web service composition problem considering multi-criteria regarding quality of services (QoS). Three different scenarios of multi-criteria mathematical programming models are explored under the framework of network based analysis in web service composition. This work takes care of the issues pertaining to inputs and outputs matching of web services and Quality-of-Service (QoS) at the same time. The multi-criteria programming models are explored to select the desirabl...
EXTENDING THE KNOWLEDGE BASE OF CHEMICAL ENGINEERING
Mooson Kwauk
2005-01-01
The obvious current reversion to micro-scale investigations in basic chemical engineering, combined with the need, of a quite different nature, in the rapid growth of high added-value and small-lot functional materials, have been pointing to an area not yet sufficiently covered by the unit operations, transport phenomena and chemical reaction engineering. Although it is difficult to define accurately this area, a cursory scan of the activities already in progress has revealed a few common attributes: multi-phased (structured), multi-scaled, multi-disciplined, nonlinear, needs for resolution to reductionism-solvable subsystems, and pervasive in the process industry. From these activities, the present paper drafts a tentative scheme for studying the related problems: first to dissect a problem into various scales - spatial, temporal or otherwise as best suits the case in hand- in order to identify pertinent parameters which are then organized into model formulations. Together with inter-scale model formulations, a zoom-in/zoom-out process is carried out between the scales, by trial-and-error and through reasoning, to arrive at a global formulation of a quantitative solution, in order to derive, eventually, the general from the particular.
Laursen, Sandra L.; Hassi, Marja-Liisa; Hough, Sarah
2016-02-01
This mixed-methods study describes classroom characteristics and student outcomes from university mathematics courses that are based in mathematics departments, targeted to future pre-tertiary teachers, and taught with inquiry-based learning (IBL) approaches. The study focused on three two-term sequences taught at two research universities, separately targeting elementary and secondary pre-service teachers. Classroom observation established that the courses were taught with student-centred methods that were comparable to those used in IBL courses for students in mathematics-intensive fields at the same institutions. To measure pre-service teachers' gains in mathematical knowledge for teaching, we administered the Learning Mathematics for Teaching (LMT) instrument developed by Hill, Ball and Schilling for in-service teacher professional development. Results from the LMT show that pre-service teachers made significant score gains from beginning to end of their course, while data from interviews and from surveys of learning gains show that pre-service teachers viewed their gains as relevant to their future teaching work. Measured changes on pre-/post-surveys of attitudes and beliefs were generally supportive of learning mathematics but modest in magnitude. The study is distinctive in applying the LMT to document pre-service teachers' growth in mathematical knowledge for teaching. The study also suggests IBL is an approach well suited to mathematics departments seeking to strengthen their pre-service teacher preparation offerings in ways consistent with research-based recommendations.
Applying Mathematical Optimization Methods to an ACT-R Instance-Based Learning Model.
Nadia Said
Full Text Available Computational models of cognition provide an interface to connect advanced mathematical tools and methods to empirically supported theories of behavior in psychology, cognitive science, and neuroscience. In this article, we consider a computational model of instance-based learning, implemented in the ACT-R cognitive architecture. We propose an approach for obtaining mathematical reformulations of such cognitive models that improve their computational tractability. For the well-established Sugar Factory dynamic decision making task, we conduct a simulation study to analyze central model parameters. We show how mathematical optimization techniques can be applied to efficiently identify optimal parameter values with respect to different optimization goals. Beyond these methodological contributions, our analysis reveals the sensitivity of this particular task with respect to initial settings and yields new insights into how average human performance deviates from potential optimal performance. We conclude by discussing possible extensions of our approach as well as future steps towards applying more powerful derivative-based optimization methods.
Chemical-Based Formulation Design: Virtual Experimentation
Conte, Elisa; Gani, Rafiqul
This paper presents a software, the virtual Product-Process Design laboratory (virtual PPD-lab) and the virtual experimental scenarios for design/verification of consumer oriented liquid formulated products where the software can be used. For example, the software can be employed for the design......, the additives and/or their mixtures (formulations). Therefore, the experimental resources can focus on a few candidate product formulations to find the best product. The virtual PPD-lab allows various options for experimentations related to design and/or verification of the product. For example, the selection...... design, model adaptation). All of the above helps to perform virtual experiments by blending chemicals together and observing their predicted behaviour. The paper will highlight the application of the virtual PPD-lab in the design and/or verification of different consumer products (paint formulation...
Dina V. Lazareva
2015-06-01
Full Text Available A new mathematical model of asymmetric support structure frame type is built on the basis of numerical-analytical boundary elements method (BEM. To describe the design scheme used is the graph theory. Building the model taken into account is the effect of frame members restrained torsion, which presence is due to the fact that these elements are thin-walled. The built model represents a real object as a two-axle semi-trailer platform. To implement the BEM algorithm obtained are analytical expressions of the fundamental functions and vector load components. The effected calculations are based on the semi-trailer two different models, using finite elements and boundary elements methods. The analysis showed that the error between the results obtained on the basis of two numerical methods and experimental data is about 4%, that indicates the adequacy of the proposed mathematical model.
Bird, John
2014-01-01
A practical introduction to the core mathematics required for engineering study and practiceNow in its seventh edition, Engineering Mathematics is an established textbook that has helped thousands of students to succeed in their exams.John Bird's approach is based on worked examples and interactive problems. This makes it ideal for students from a wide range of academic backgrounds as the student can work through the material at their own pace. Mathematical theories are explained in a straightforward manner, being supported by practical engineering examples and applications in order to ensure
Geroch, Robert
1900-01-01
Mathematical Physics is an introduction to such basic mathematical structures as groups, vector spaces, topological spaces, measure spaces, and Hilbert space. Geroch uses category theory to emphasize both the interrelationships among different structures and the unity of mathematics. Perhaps the most valuable feature of the book is the illuminating intuitive discussion of the ""whys"" of proofs and of axioms and definitions. This book, based on Geroch's University of Chicago course, will be especially helpful to those working in theoretical physics, including such areas as relativity, particle
A FRET-based probe with a chemically deactivatable quencher.
Leriche, Geoffray; Budin, Ghyslain; Darwich, Zeinab; Weltin, Denis; Mély, Yves; Klymchenko, Andrey S; Wagner, Alain
2012-03-28
A new concept of a chemically deactivatable quencher is proposed for a FRET-based probe that turns-on its fluorescence by either an enzymatic cleavage or a chemical reagent (sodium dithionite). This concept allowed us to quantify the caspase-3 cleavage activity in solution and to reveal unreacted probes in cell experiments. PMID:22327268
A decision analytic approach to exposure-based chemical prioritization.
Jade Mitchell
Full Text Available The manufacture of novel synthetic chemicals has increased in volume and variety, but often the environmental and health risks are not fully understood in terms of toxicity and, in particular, exposure. While efforts to assess risks have generally been effective when sufficient data are available, the hazard and exposure data necessary to assess risks adequately are unavailable for the vast majority of chemicals in commerce. The US Environmental Protection Agency has initiated the ExpoCast Program to develop tools for rapid chemical evaluation based on potential for exposure. In this context, a model is presented in which chemicals are evaluated based on inherent chemical properties and behaviorally-based usage characteristics over the chemical's life cycle. These criteria are assessed and integrated within a decision analytic framework, facilitating rapid assessment and prioritization for future targeted testing and systems modeling. A case study outlines the prioritization process using 51 chemicals. The results show a preliminary relative ranking of chemicals based on exposure potential. The strength of this approach is the ability to integrate relevant statistical and mechanistic data with expert judgment, allowing for an initial tier assessment that can further inform targeted testing and risk management strategies.
Post secondary project-based learning in science, technology, engineering and mathematics
Rachel A Ralph
2016-01-01
Project-based learning (PjBL - to distinguish from problem-based learning - PBL) has become a recurrent practice in K-12 classroom environments. As PjBL has become prominent in K-12 classrooms, it has also surfaced in post-secondary institutions. The purpose of this paper is to examine the research that has studied a variety of science, technology, engineering and mathematic subjects using PjBL in post-secondary classrooms. Eleven articles (including qualitative, quantitative and mixed metho...
3DTS: A 3D tolerancing system based on mathematical definition
CAO Yan-long; LIU Yu-sheng; MAO Jian; YANG Jiang-xin
2006-01-01
Tolerance is almost ubiquitous during the whole product lift cycle and is imperative for seamless integration of CAD and CAM. Based on the mathematical definition of tolerance, a 3D tolerancing system, 3DTS, is presented with its design principle, system architecture and key functions. The following functional modules, tolerance modeling, semantics interpretation, 3D tolerance analysis, are described in detail. To make the tolerancing system robust and efficient, many techniques such as hierarchical tolerance representation, rule-based evaluation and non-intersection determination of tolerance zone have been devised.Tested by many samples, this system shows good robustness and practicability.
Nutti, Ylva Jannok
2013-03-01
The goal of Indigenous education is that it should be approached on the basis of the Indigenous language and culture; this is also the case with Sámi education. The Sámi School Board has stated that all teaching in Sámi schools should be culturally based, despite the fact that Sámi culture-based teaching is not specifically defined. Therefore, teachers themselves must adapt the teaching and as a result, usually no Sámi culture-based mathematics teaching takes place. The aim of this article is to discuss Indigenous teachers' experiences with designing and implementing culture-based mathematics activities in Sámi preschool and primary school. The teachers' work with culture-based mathematics activities took the form of Sámi cultural thematic work with ethnomathematical content, Multicultural school mathematics with Sámi cultural elements, and Sámi intercultural mathematics teaching. Culture-based mathematics activities took place within an action research study in the Swedish part of Sápmi. Sápmi comprises northern Norway, Sweden, and Finland, as well as the Kola Peninsula in Russia. In the action research study, six teachers conducted culture-based mathematics activities in preschool and primary school on the basis of the action research loop "plan-act-observe-reflect." During the study the teachers changed from a problem-focused perspective to a possibility-focused culture-based teaching perspective characterised by a self-empowered Indigenous teacher role, as a result of which they started to act as agents for Indigenous school change. The concept of "decolonisation" was visible in the teachers' narratives. The teachers' newly developed knowledge about the ethnomathematical research field seemed to enhance their work with Indigenous culture-based mathematics teaching.
Chemical Mixture Risk Assessment Additivity-Based Approaches
Powerpoint presentation includes additivity-based chemical mixture risk assessment methods. Basic concepts, theory and example calculations are included. Several slides discuss the use of "common adverse outcomes" in analyzing phthalate mixtures.
Rubin, Andrew
2014-01-01
This book presents concise descriptions and analysis of the classical and modern models used in mathematical biophysics. The authors ask the question "what new information can be provided by the models that cannot be obtained directly from experimental data?" Actively developing fields such as regulatory mechanisms in cells and subcellular systems and electron transport and energy transport in membranes are addressed together with more classical topics such as metabolic processes, nerve conduction and heart activity, chemical kinetics, population dynamics, and photosynthesis. The main approach is to describe biological processes using different mathematical approaches necessary to reveal characteristic features and properties of simulated systems. With the emergence of powerful mathematics software packages such as MAPLE, Mathematica, Mathcad, and MatLab, these methodologies are now accessible to a wide audience. Provides succinct but authoritative coverage of a broad array of biophysical topics and models Wr...
Thin-film chemical sensors based on electron tunneling
Khanna, S. K.; Lambe, J.; Leduc, H. G.; Thakoor, A. P.
1985-01-01
The physical mechanisms underlying a novel chemical sensor based on electron tunneling in metal-insulator-metal (MIM) tunnel junctions were studied. Chemical sensors based on electron tunneling were shown to be sensitive to a variety of substances that include iodine, mercury, bismuth, ethylenedibromide, and ethylenedichloride. A sensitivity of 13 parts per billion of iodine dissolved in hexane was demonstrated. The physical mechanisms involved in the chemical sensitivity of these devices were determined to be the chemical alteration of the surface electronic structure of the top metal electrode in the MIM structure. In addition, electroreflectance spectroscopy (ERS) was studied as a complementary surface-sensitive technique. ERS was shown to be sensitive to both iodine and mercury. Electrolyte electroreflectance and solid-state MIM electroreflectance revealed qualitatively the same chemical response. A modified thin-film structure was also studied in which a chemically active layer was introduced at the top Metal-Insulator interface of the MIM devices. Cobalt phthalocyanine was used for the chemically active layer in this study. Devices modified in this way were shown to be sensitive to iodine and nitrogen dioxide. The chemical sensitivity of the modified structure was due to conductance changes in the active layer.
Piezoresistive Chemical Sensors Based on Functionalized Hydrogels
Margarita Guenther
2014-06-01
Full Text Available Thin films of analyte-specific hydrogels were combined with microfabricated piezoresistive pressure transducers to obtain chemomechanical sensors that can serve as selective biochemical sensors for a continuous monitoring of metabolites. The gel swelling pressure has been monitored in simulated physiological solutions by means of the output signal of piezoresistive sensors. The interference by fructose, human serum albumin, pH, and ionic concentration on glucose sensing was studied. With the help of a database containing the calibration curves of the hydrogel-based sensors at different values of pH and ionic strength, the corrected values of pH and glucose concentration were determined using a novel calibration algorithm.
Hongli Liu
2012-11-01
Full Text Available Adopting the microscopic observation imaging and digital image processing technologies, this paper researches a new measuring method of indoor inhalable particulate matter concentration and size distribution .It realizes denoising, binarization, filtering and edge detection to based on mathematical morphology, regional filled and calibration detection to particulate matter image, designs the parameters recognition algorithm for particulate matter size, fractal dimension ,shape factors and so on, then calculates the concentration and size distribution of particulate matter using data fusion method. The experimental results show that the method has advantages with intuitive, high precision, fast processing speed ,easily data statistics, clearly data analysis and stable measuring results.
New Mathematical Model Based on Affine Transformation for Remote Sensing Image with High Resolution
无
2003-01-01
This paper calculates the parameters of image position and orientation,proposes a mathematical model and adopts a new method with three steps of transformations based on parallel ray projection.Every step of the model is strict,and the map function of each transformation is the first order polynomials and other simple function.The final calculation of the parameters is for the linear equations with good status.As a result,the problem of the relativity of image parameter calculation is solved completely.Some experiments are carried out.
Firefly Optimization and Mathematical Modeling of a Vehicle Crash Test Based on Single-Mass
Andreas Klausen; Sondre Sanden Tørdal; Hamid Reza Karimi; Robbersmyr, Kjell G.; Mladen Jecmenica; Ole Melteig
2014-01-01
In this paper mathematical modeling of a vehicle crash test based on a single-mass is studied. The model under consideration consists of a single-mass coupled with a spring and/or a damper. The parameters for the spring and damper are obtained by analyzing the measured acceleration in the center of gravity of the vehicle during a crash. A model with a nonlinear spring and damper is also proposed and the parameters will be optimized with different damper and spring characteristics and optimiza...
Perspectives of IT Artefacts: Information Systems based on Complex Mathematical Models
Carugati, Andrea
2002-01-01
A solution for production scheduling that is lately attracting the interests of the manufacturing industry involves the use of complex mathematical modeling techniques in scheduling software. However this technology is fairly unknown among manufacturing practitioners, as are the social problems o...... its development and use. The aim of this article is to show how an approach based on multiple perspectives can help understand the emergence of complex software and help understand why and how the reasons and motives of the different stakeholders are, at times, incompatible....
Mathematical model of turnout electric drive work based on a linear motor.
МАСЛИЙ, Ар С; МАСЛИЙ, Ан С; БУРЯКОВСКИЙ, С. Г.; Любарский, Б. Г.
2015-01-01
The article considers mathematical model of electric drive work based on a linear motor. Linear motors are electric induction motors that produce motion in a straight line rather than rotational motion. They are now used in all sorts of machines that require linear (as opposed to rotational) motion, including overhead traveling cranes and beltless conveyors for moving sheet metal. They are probably best known as the source of motive power in the latest generation of high-speed magnetic levita...
Phylogenetic Analysis of H7N9 Avian Influenza Virus Based on a Novel Mathematical Descriptor
Yusheng Bai; Tingting Ma; Yuhua Yao; Qi Dai; Ping-an He
2014-01-01
A new mathematical descriptor was proposed based on 3D graphical representation. Using the method, we construct the phylogenetic trees of nine proteins of H7N9 influenza virus to analyze the originated source of H7N9. The results show that the evolution route of H7N9 avian influenza is from America through Europe to Asia. Furthermore, two samples collected from environment in Nanjing and Zhejiang and one sample collected from chicken are the sources of H7N9 influenza virus that infected human...
Plasmonics Based Harsh Environment Compatible Chemical Sensors
Michael Carpenter
2012-01-15
Au-YSZ, Au-TiO{sub 2} and Au-CeO{sub 2} nanocomposite films have been investigated as a potential sensing element for high-temperature plasmonic sensing of H{sub 2}, CO, and NO{sub 2} in an oxygen containing environment. The Au-YSZ and Au-TiO{sub 2} films were deposited using PVD methods, while the CeO{sub 2} thin film was deposited by molecular beam epitaxy (MBE) and Au was implanted into the as-grown film at an elevated temperature followed by high temperature annealing to form well-defined Au nanoclusters. Each of the films were characterized by x-ray diffraction (XRD) and Rutherford backscattering spectrometry (RBS). For the gas sensing experiments, separate exposures to varying concentrations of H{sub 2}, CO, and NO{sub 2} were performed at a temperature of 500Â°C in oxygen backgrounds of 5.0, 10, and ~21% O{sub 2}. Changes in the localized surface plasmon resonance (LSPR) absorption peak were monitored during gas exposures and are believed to be the result of oxidation-reduction processes that fill or create oxygen vacancies in the respective metal oxides. This process affects the LSPR peak position either by charge exchange with the Au nanoparticles or by changes in the dielectric constant surrounding the particles. Hyperspectral multivariate analysis was used to gauge the inherent selectivity of the film between the separate analytes. From principal component analysis (PCA), unique and identifiable responses were seen for each of the analytes. Linear discriminant analysis (LDA) was also used on the Au-CeO{sub 2} results and showed separation between analytes as well as trends in gas concentration. Results indicate that each of the films are is selective towards O{sub 2}, H{sub 2}, CO, and NO{sub 2} in separate exposures. However, when the films were analyzed in a sensor array based experiment, ie simultaneous exposures to the target gases, PCA analysis of the combined response showed an even greater selective character towards the target gases. Combined
Nondestructive inspection of chemical warfare based on API-TOF
Background: Real-time, fast, accurate, nondestructive inspection (NDI) and quantitative analysis for chemical warfare are very imperative for chemical defense, anti-terror and nation security. Purpose: Associated Particles Technique (APT)/Neutron Time of Flight (TOF) has been developed for non-invasive inspection of sealed containers with chemical warfare agents. Methods: A prototype equipment for chemical warfare is consisted of an APT neutron generator with a 3×3 matrix of semiconductor detectors of associated alpha-particles, the shielding protection of neutron and gamma-ray, arrayed NaI(Tl)-based detectors of gamma-rays, fully-digital data acquisition electronics, data analysis, decision-making software, support platform and remote control system. Inelastic scattering gamma-ray pulse height spectra of sarin, VX, mustard gas and adamsite induced by 14-MeV neutron are measured. The energies of these gamma rays are used to identify the inelastic scattering elements, and the intensities of the peaks at these energies are used to reveal their concentrations. Results: The characteristic peaks of inelastic scattering gamma-ray pulse height spectra show that the prototype equipment can fast and accurately inspect chemical warfare. Conclusion: The equipment can be used to detect not only chemical warfare agents but also other hazardous materials, such as chemical/toxic/drug materials, if their chemical composition is in any way different from that of the surrounding materials. (authors)
Utilization of chemical abstracts service (CAS) data bases
A method is developed describing the economic utilization of the Chemical Abstracts Service data bases CA Condensates and Chemical Abstracts Subject Index Alertin order to supplement the data base of the IDC-Inorganica-Documentationsystem built up to meet the peculiarities of the inorganic chemistry. The method consists of EDP-Programs and processes at which special authority files for coded compound and subject entries play an important role. One of the advantages of the method is that the intellectual effort necessary to create such a data base is reduced to a minimum. The authority files may be also used for orther purposes. (orig.) 891 WB 892 MB
A novel mathematical technique to assess of the mitral valve dynamics based on echocardiography
Karvandi, Mersedeh; Hassantash, Seyed Ahmad; Foroughi, Mahnoosh
2015-01-01
Purpose: The mechanics of the mitral valve leaflet as a nonlinear, inelastic and anisotropic soft tissue results from an integrated response of many mathematical/physical indexes' that illustrate the tissue. In the past decade, finite element modeling of complete heart valves has greatly aided evaluation of heart valve surgery, design of bioprosthetic valve replacements, and general understanding of healthy and abnormal cardiac function. Such a model must be based on an accurate description of the mechanical behavior of the valve material. It is essential to calculate velocity/displacement and strain rate/strain at a component level that is to work at the cellular level. In this study we developed the first three-dimensional displacement vectors field in the characterization of mitral valve leaflets in continuum equations of inelasticity framework based on echocardiography. Method: Much of our knowledge of abnormal mitral valve function is based on surgical and post-mortem studies while these studies are quan...
Chemical Functionalization Effects on Cubane-Based Chain Electronic Transport
Konstantin P. Katin; Mikhail M. Maslov
2015-01-01
We report electronic structure calculations in chemically functionalized linear cubane-based chains. The effects of covalent chemical attachments on chain transport properties are examined with nonorthogonal tight-binding model (NTBM) considering Landauer-Büttiker formalism. The covalent bonding of even a single-type functional group is shown to considerably alter the conductance of the chain. For similar radical doping density, electronic characteristics are found to range from insulator to ...
Graphene Electronic Device Based Biosensors and Chemical Sensors
Jiang, Shan
2014-01-01
Two-dimensional layered materials, such as graphene and MoS2, are emerging as an exciting material system for a new generation of atomically thin electronic devices. With their ultrahigh surface to volume ratio and excellent electrical properties, 2D-layered materials hold the promise for the construction of a generation of chemical and biological sensors with unprecedented sensitivity. In my PhD thesis, I mainly focus on graphene based electronic biosensors and chemical sensors. In the first...
Evaluation of thorium based nuclear fuel. Chemical aspects
This report describes the chemical aspects of a thorium-based fuel cycle. It is part of a series devoted to the study of thorium-based fuel as a means to achieve a considerable reduction of the radiotoxicity of the waste from nuclear power production. Therefore special emphasis is placed on fuel (re-)fabrication and fuel reprocessing in the present work. (orig.)
M. N. Modebelu; C. C. Ogbonna
2014-01-01
This study aimed at determining the effect of reform-based-instructional method learning styles on students’ achievement and retention in mathematics. A sample size of 119 students was randomly selected. The quasi-experimental design comprising pre-test, post-test, and randomized control group were employed. The Collin Rose learning styles identification and Mathematics instrument were used for data collection. Data collected were analyzed using mean, standard deviation and analysis of covari...
Mathematical methods are being increasingly employed in the efficiency calibration of gamma based systems for non-destructive assay (NDA) of radioactive waste and for the estimation of the Total Measurement Uncertainty (TMU). Recently, ASTM (American Society for Testing and Materials) released a standard guide for use of modeling passive gamma measurements. This is a testimony to the common use and increasing acceptance of mathematical techniques in the calibration and characterization of NDA systems. Mathematical methods offer flexibility and cost savings in terms of rapidly incorporating calibrations for multiple container types, geometries, and matrix types in a new waste assay system or a system that may already be operational. Mathematical methods are also useful in modeling heterogeneous matrices and non-uniform activity distributions. In compliance with good practice, if a computational method is used in waste assay (or in any other radiological application), it must be validated or benchmarked using representative measurements. In this paper, applications involving mathematical methods in gamma based NDA systems are discussed with several examples. The application examples are from NDA systems that were recently calibrated and performance tested. Measurement based verification results are presented. Mathematical methods play an important role in the efficiency calibration of gamma based NDA systems. This is especially true when the measurement program involves a wide variety of complex item geometries and matrix combinations for which the development of physical standards may be impractical. Mathematical methods offer a cost effective means to perform TMU campaigns. Good practice demands that all mathematical estimates be benchmarked and validated using representative sets of measurements. (authors)
LIN Hui; DU Pei-jun; ZHAO Chang-sheng; SHU Ning
2004-01-01
This paper puts forward an effective,specific algorithm for edge detection.Based on multi-structure elements of gray mathematics morphology,in the light of difference between noise and edge shape of RS images,the paper establishes multi-structure elements to detect edge by utilizing the grey form transformation principle.Compared with some classical edge detection operators,such as Sobel Edge Detection Operator,LOG Edge Detection Operator,and Canny Edge Detection Operator,the experiment indicates that this new algorithm possesses very good edge detection ability,which can detect edges more effectively,but its noise-resisting ability is relatively low.Because of the bigger noise of remote sensing image,the authors probe into putting forward other edge detection method based on combination of wavelet directivity checkout technology and small-scale Mathematical Morphology finally.So,position at the edge can be accurately located,the noise can be inhibited to a certain extent and the effect of edge detection is obvious.
Najman, Laurent
2013-01-01
Mathematical Morphology allows for the analysis and processing of geometrical structures using techniques based on the fields of set theory, lattice theory, topology, and random functions. It is the basis of morphological image processing, and finds applications in fields including digital image processing (DSP), as well as areas for graphs, surface meshes, solids, and other spatial structures. This book presents an up-to-date treatment of mathematical morphology, based on the three pillars that made it an important field of theoretical work and practical application: a solid theoretical foun
Computing multi-species chemical equilibrium with an algorithm based on the reaction extents
Paz-Garcia, Juan Manuel; Johannesson, Björn; Ottosen, Lisbeth M.;
2013-01-01
A mathematical model for the solution of a set of chemical equilibrium equations in a multi-species and multiphase chemical system is described. The computer-aid solution of model is achieved by means of a Newton-Raphson method enhanced with a line-search scheme, which deals with the non-negative...
Review of Evidence-Based Mathematics Interventions for Students with Autism Spectrum Disorders
Hart Barnett, Juliet E.; Cleary, Shannon
2015-01-01
Students with autism spectrum disorders (ASD) are being included more frequently in the general educational setting, and are therefore increasingly expected to access and master core curricular content, including mathematics. However, mathematics often presents challenges to students with ASD. Interventions to improve the mathematics skills of…
Teaching Secondary School Mathematics and Statistics: Evidence-Based Practice. Volume 2
Averill, Robin; Harvey, Roger
2009-01-01
"We can never be sure that there is not some wild, untamed piece of mathematics ready to spring out on us... This is what keeps mathematics enchanting." This is how Jim Neyland, one of the contributing authors to this book, describes mathematics. His enthusiasm and energy are echoed throughout by many of the other writers. This is a book to…
Teaching Secondary School Mathematics and Statistics: Evidence-Based Practice. Volume 1
Averill, Robin; Harvey, Roger
2009-01-01
"Mathematics is more than skills... it is also the excitement of discovery." This is how Derek Holton, one of the contributing authors to this book, defines mathematics. His enthusiasm and energy are echoed throughout by many of the other writers. This is a book to delight mathematics teachers at all stages: experienced and inexperienced;…
Mathematical Modeling of Biosensors Based on an Array of Enzyme Microreactors
Baronas, Romas; Ivanauskas, Feliksas; Kulys, Juozas
2006-01-01
This paper presents a two-dimensional-in-space mathematical model of biosensors based on an array of enzyme microreactors immobilised on a single electrode. The modeling system acts under amperometric conditions. The microreactors were modeled by particles and by strips. The model is based on the diffusion equations containing a non-linear term related to the Michaelis-Menten kinetics of the enzymatic reaction. The model involves three regions: an array of enzyme microreactors where enzyme reaction as well as mass transport by diffusion takes place, a diffusion limiting region where only the diffusion takes place, and a convective region, where the analyte concentration is maintained constant. Using computer simulation, the influence of the geometry of the microreactors and of the diffusion region on the biosensor response was investigated. The digital simulation was carried out using the finite difference technique.
Mathematical Modeling of Biosensors Based on an Array of Enzyme Microreactors
Juozas Kulys
2006-04-01
Full Text Available This paper presents a two-dimensional-in-space mathematical model ofbiosensors based on an array of enzyme microreactors immobilised on a single electrode.The modeling system acts under amperometric conditions. The microreactors were modeledby particles and by strips. The model is based on the diffusion equations containing a non-linear term related to the Michaelis-Menten kinetics of the enzymatic reaction. The modelinvolves three regions: an array of enzyme microreactors where enzyme reaction as well asmass transport by diffusion takes place, a diffusion limiting region where only the diffusiontakes place, and a convective region, where the analyte concentration is maintained constant.Using computer simulation, the influence of the geometry of the microreactors and of thediffusion region on the biosensor response was investigated. The digital simulation wascarried out using the finite difference technique.
Charafi, My. M.; Sadok, A.; Kamal, A.; Menai, A.
A quasi-three-dimensional mathematical model has been developed to study the morphological processes based on equilibrium sediment transport method. The flow velocities are computed by a two-dimensional horizontal depth-averaged flow model (H2D) in combination with logarithmic velocity profiles. The transport of sediment particles by a flow water has been considered in the form of bed load and suspended load. The bed load transport rate is defined as the transport of particles by rolling and saltating along the bed surface and is given by the Van Rijn relationship (1987). The equilibrium suspended load transport is described in terms of an equilibrium sediment concentration profile (ce) and a logarithmic velocity (u). Based on the equilibrium transport, the bed change rate is given by integration of the sediment mass-balance equation. The model results have been compared with a Van Rijn results (equilibrium approach) and good agreement has been found.
High intensive microwave pretreatment is a new method to modify wood for the fabrication of wood-based nano composites. Based on the physical law on heat transfer, a mathematical model to describe the temperature profiles within wood heated by high intensive microwave was established and simulated in this research. The results showed that the temperature profiles within wood were related to microwave heating methods; The temperature inside wood firstly increased and then gradually decreased along the direction of microwave transmission when the unilateral microwave heating was applied, and the temperature difference along the thickness direction of wood was very significant; The temperature with wood firstly increased and then gradually decreased from the wood surface to interior when the bilateral microwave heating was applied. Compared with the unilateral microwave heating, bilateral microwave heating is a better microwave heating method for the more uniform wood microwave pretreatment.
Carugati, Andrea
2002-01-01
systems development. In a presented case the indications of the model are compared with the decisions taken during the development. The results highlight discrepancies between the structure and predictions of the model and the case observations, especially with regard to the importance given to the users......’ skills in the development process. Further observations also indicate that flexibility and adaptability, based on grounded theory, are valuable tools when information systems development involves a new technology....... has been initiated with the scope of investigating the questions that mathematical modelling technology poses to traditional information systems development projects. Based on the past body of research, this study proposes a framework to guide decision making for managing projects of information...
Structural and Chemical Diversity of Tl-Based Cuprate Superconductors
信赢
2003-01-01
The Tl-based cuprate superconductor family is the largest family in crystal structure and chemical composition among all high Tc cuprate superconductors. The Tl family can be divided into two sub-families, the Tl single layer family and the Tl double layer family, based on their crystal structural characteristics. The Tl single layer family is an ideal material for investigating the evolution of crystalline formation, charge carrier density, chemical composition, transport properties, superconductivity and their relationships. The Tl family contains almostall possible crystal structures discovered in high-Tc cuprate superconductors. Tl cuprate superconductors are of great importance not only in studying high-temperature superconductivity but also in commercial applications.
Chemical Functionalization Effects on Cubane-Based Chain Electronic Transport
Konstantin P. Katin
2015-01-01
Full Text Available We report electronic structure calculations in chemically functionalized linear cubane-based chains. The effects of covalent chemical attachments on chain transport properties are examined with nonorthogonal tight-binding model (NTBM considering Landauer-Büttiker formalism. The covalent bonding of even a single-type functional group is shown to considerably alter the conductance of the chain. For similar radical doping density, electronic characteristics are found to range from insulator to narrow-gap semiconductor depending on the nature of the covalent bonding. Therefore it has become possible to tune electronic properties of the cubane-based one-dimensional oligomers by the functionalization for nanoelectronic applications.
Sayantan Nath
2015-09-01
Full Text Available In this paper, integration between multiple functions of image processing and its statistical parameters for intelligent alarming series based fire detection system is presented. The proper inter-connectivity mapping between processing elements of imagery based on classification factor for temperature monitoring and multilevel intelligent alarm sequence is introduced by abstractive canonical approach. The flow of image processing components between core implementation of intelligent alarming system with temperature wise area segmentation as well as boundary detection technique is not yet fully explored in the present era of thermal imaging. In the light of analytical perspective of convolutive functionalism in thermal imaging, the abstract algebra based inter-mapping model between event-calculus supported DAGSVM classification for step-by-step generation of alarm series with gradual monitoring technique and segmentation of regions with its affected boundaries in thermographic image of coal with respect to temperature distinctions is discussed. The connectedness of the multifunctional operations of image processing based compatible fire protection system with proper monitoring sequence is presently investigated here. The mathematical models representing the relation between the temperature affected areas and its boundary in the obtained thermal image defined in partial derivative fashion is the core contribution of this study. The thermal image of coal sample is obtained in real-life scenario by self-assembled thermographic camera in this study. The amalgamation between area segmentation, boundary detection and alarm series are described in abstract algebra. The principal objective of this paper is to understand the dependency pattern and the principles of working of image processing components and structure an inter-connected modelling technique also for those components with the help of mathematical foundation.
Lee, Chang Jun
2015-01-01
In the fields of researches associated with plant layout optimization, the main goal is to minimize the costs of pipelines and pumping between connecting equipment under various constraints. However, what is the lacking of considerations in previous researches is to transform various heuristics or safety regulations into mathematical equations. For example, proper safety distances between equipments have to be complied for preventing dangerous accidents on a complex plant. Moreover, most researches have handled single-floor plant. However, many multi-floor plants have been constructed for the last decade. Therefore, the proper algorithm handling various regulations and multi-floor plant should be developed. In this study, the Mixed Integer Non-Linear Programming (MINLP) problem including safety distances, maintenance spaces, etc. is suggested based on mathematical equations. The objective function is a summation of pipeline and pumping costs. Also, various safety and maintenance issues are transformed into inequality or equality constraints. However, it is really hard to solve this problem due to complex nonlinear constraints. Thus, it is impossible to use conventional MINLP solvers using derivatives of equations. In this study, the Particle Swarm Optimization (PSO) technique is employed. The ethylene oxide plant is illustrated to verify the efficacy of this study. PMID:26027708
Optimization of Cooling Process of Iron Ore Pellets Based on Mathematical Model and Data Mining
Gui-ming YANG; Xiao-hui FAN; Xu-ling CHEN; Xiao-xian HUANG; Xi LI
2015-01-01
Cooling process of iron ore pellets in a circular cooler has great impacts on the pellet quality and systematic energy exploitation. However, multi-variables and non-visualization of this gray system is unfavorable to efifcient production. Thus, the cooling process of iron ore pellets was optimized using mathematical model and data mining techniques. A mathematical model was established and validated by steady-state production data, and the results show that the calculated values coincide very well with the measured values. Based on the proposed model, effects of important process parameters on gas-pellet temperature proifles within the circular cooler were analyzed to better understand the entire cooling process. Two data mining techniques—Associa-tion Rules Induction and Clustering were also applied on the steady-state production data to obtain expertise operating rules and optimized targets. Finally, an optimized control strategy for the circular cooler was proposed and an operation guidance system was developed. The system could realize the visualization of thermal process at steady state and provide operation guidance to optimize the circular cooler.
Improving Mathematical Optimization Techniques with the Aid of Exergy-Based Variables
George Tsatsaronis
2009-06-01
Full Text Available
The design optimization of energy conversion plants requires sophisticated optimization techniques. The usefulness of mathematical programming approaches has been discussed in several papers. Usually, the quality of the computed solutions, concerning global optimality and the convergence speed, is not discussed in these papers and even the existence of local optimal solutions is not mentioned. Indeed, the optimization of nonconvex mixed integer non-linear problems (MINLP, such as the structural and design optimization of power plants, is a very difficult problem. However, knowledge of the real optimization potential can assist the design engineer in better understanding the optimization procedure. This article deals with the use of exergetic variables for improving the quality of results obtained from mathematical optimization techniques and their convergence speed. LaGO, the solver used to compute the discussed results, can evaluate the obtained solution of the discussed minimization problems by calculating lower bounds of the original problem based on a relaxed convex objective function. Here, the use of exergetic variables can help to increase the lower bounds significantly and thus, to improve the evaluation of the computed solutions and the convergence speed. The method is applied to different optimization tasks.
Satellite-rocket docking ring recognition method based on mathematical morphology
Xu, Zhiqiang; Shang, Yang; Ma, Xuan
2015-10-01
Satellite-rocket docking ring recognition method based on mathematical morphology is presented in this paper, according to the geometric and grayscale characteristics of the docking ring typical structure. The docking ring used in this paper is a circle with a cross in the middle. Most of spacecrafts are transported into orbit by rocket, and they retain the connection component with the rocket. The tracing spacecraft should capture the target spacecraft first before operating the target spacecraft. The docking ring is one of the typical parts of a spacecraft, and it can be recognized automatically. Thereby we can capture the spacecraft through the information of the docking ring. Firstly a multi-step mathematical morphology processing is applied to the image of the target spacecraft with different structure element, followed by edge detection and line detection, and finally docking ring typical structure is located in the image by relative geometry analysis. The images used in this paper are taken of real satellite in lab. The docking ring can be recognized when the distance between the two spacecraft is different. The results of physical simulation experiment show that the method in this paper can recognize docking ring typical structure accurately when the tracing spacecraft is approaching the target spacecraft.
Modelers' perception of mathematical modeling in epidemiology: a web-based survey.
Gilles Hejblum
Full Text Available BACKGROUND: Mathematical modeling in epidemiology (MME is being used increasingly. However, there are many uncertainties in terms of definitions, uses and quality features of MME. METHODOLOGY/PRINCIPAL FINDINGS: To delineate the current status of these models, a 10-item questionnaire on MME was devised. Proposed via an anonymous internet-based survey, the questionnaire was completed by 189 scientists who had published in the domain of MME. A small minority (18% of respondents claimed to have in mind a concise definition of MME. Some techniques were identified by the researchers as characterizing MME (e.g. Markov models, while others-at the same level of sophistication in terms of mathematics-were not (e.g. Cox regression. The researchers' opinions were also contrasted about the potential applications of MME, perceived as highly relevant for providing insight into complex mechanisms and less relevant for identifying causal factors. The quality criteria were those of good science and were not related to the size and the nature of the public health problems addressed. CONCLUSIONS/SIGNIFICANCE: This study shows that perceptions on the nature, uses and quality criteria of MME are contrasted, even among the very community of published authors in this domain. Nevertheless, MME is an emerging discipline in epidemiology and this study underlines that it is associated with specific areas of application and methods. The development of this discipline is likely to deserve a framework providing recommendations and guidance at various steps of the studies, from design to report.
Westphael, Henning; Mogensen, Arne
2013-01-01
In this article we present the notion of Mathematical competences as a tool to describe the mathematically gifted students.......In this article we present the notion of Mathematical competences as a tool to describe the mathematically gifted students....
Applied mathematics for science and engineering
Glasgow, Larry A
2014-01-01
Prepare students for success in using applied mathematics for engineering practice and post-graduate studies moves from one mathematical method to the next sustaining reader interest and easing the application of the techniques Uses different examples from chemical, civil, mechanical and various other engineering fields Based on a decade's worth of the authors lecture notes detailing the topic of applied mathematics for scientists and engineers Concisely writing with numerous examples provided including historical perspectives as well as a solutions manual for academic adopters
Chemical Information in Scirus and BASE (Bielefeld Academic Search Engine)
Bendig, Regina B.
2009-01-01
The author sought to determine to what extent the two search engines, Scirus and BASE (Bielefeld Academic Search Engines), would be useful to first-year university students as the first point of searching for chemical information. Five topics were searched and the first ten records of each search result were evaluated with regard to the type of…
Durable chemical sensors based on field-effect transistors
Reinhoudt, D.N.
1995-01-01
The design of durable chemical sensors based on field-effect transistors (FETs) is described. After modification of an ion-sensitive FET (ISFET) with a polysiloxane membrane matrix, it is possible to attach all electroactive components covalently. Preliminary results of measurements with a sodium-se
Kurtulus, Aytac
2013-01-01
The aim of this study was to investigate the effects of web-based interactive virtual tours on the development of prospective mathematics teachers' spatial skills. The study was designed based on experimental method. The "one-group pre-test post-test design" of this method was taken as the research model. The study was conducted with 3rd year…
Mathematical problems for chemistry students
Pota, Gyorgy
2006-01-01
Mathematical Problems for Chemistry Students has been compiled and written (a) to help chemistry students in their mathematical studies by providing them with mathematical problems really occurring in chemistry (b) to help practising chemists to activate their applied mathematical skills and (c) to introduce students and specialists of the chemistry-related fields (physicists, mathematicians, biologists, etc.) into the world of the chemical applications. Some problems of the collection are mathematical reformulations of those in the standard textbooks of chemistry, other
Mathematical problems for chemistry students
Pota, Gyorgy
2011-01-01
Mathematical Problems for Chemistry Students has been compiled and written (a) to help chemistrystudents in their mathematical studies by providing them with mathematical problems really occurring in chemistry (b) to help practising chemists to activate their applied mathematical skills and (c) to introduce students and specialistsof the chemistry-related fields (physicists, mathematicians, biologists, etc.) intothe world of the chemical applications.Some problems of the collection are mathematical reformulations of those in the standard textbooks of chemistry, others we
Harper, Marc
2013-01-01
We show that individual topics and skills can have a dramatic effect on the outcomes of students in various mathematics courses at the University of Illinois. Data from the placement program at Illinois associates a knowledge state, a subset of 182 items and skills that a student is able to complete successfully and repeatedly, with their final grades in a variety of courses from college algebra through multivariate calculus. Using various conditional probabilities and odds ratios, we classify items based on their association with successful and unsuccessful course outcomes, showing that some skills that are advanced for some courses are fundamental or basic to more advanced courses. We examine the impact of specific items across the courses in the traditional college algebra, precalculus, and calculus sequence, as well as courses not typically covered by placement programs, such as higher calculus courses. Visualizations of the knowledge states associated to each student are given for some specific courses a...
Research on Routing Algorithm Based on Limitation Arrangement Principle in Mathematics
Jianhui Lv
2014-01-01
Full Text Available Since the research on information consistency of the whole network under OSPF protocol has been insufficient in recent years, an algorithm based on limitation arrangement principle for routing decision is proposed and it is a permutation and combination problem in mathematical area. The most fundamental function of this algorithm is to accomplish the information consistency of the whole network at a relatively fast speed. Firstly, limitation arrangement principle algorithm is proposed and proved. Secondly, LAP routing algorithm in single link network and LAP routing algorithm in single link network with multiloops are designed. Finally, simulation experiments are worked by VC6.0 and NS2, which proves that LAPSN algorithm and LAPSNM algorithm can solve the problem of information consistency of the whole network under OSPF protocol and LAPSNM algorithm is superior to Dijkstra algorithm.
Characterization of Chemical and Mechanical Properties of Polymer Based Nanocomposites
Wafy, Tamer
2013-01-01
Characterization of Chemical and Mechanical Properties of Polymer Based NanocompositesThe University of ManchesterTamer Wafy Doctor of Philosophy17 January, 2013One of the most significant issues in nanocomposite performance is improving the dispersion of carbon nanotubes (CNTs) in thermosetting or thermoplastic polymers in order to gain good mechanical properties. Several studies have investigated the fabrication of nanocomposites based on carbon nanotubes and analysed properties, but there ...
The Formalization of Syntax-Based Mathematical Algorithms Using Quotation and Evaluation
Farmer, William M.
2013-01-01
Algorithms like those for differentiating functional expressions manipulate the syntactic structure of mathematical expressions in a mathematically meaningful way. A formalization of such an algorithm should include a specification of its computational behavior, a specification of its mathematical meaning, and a mechanism for applying the algorithm to actual expressions. Achieving these goals requires the ability to integrate reasoning about the syntax of the expressions with reasoning about ...
A pilot home-based early intervention study to improve the mathematical skills of young children
Ayşegül Şükran Öz
2013-01-01
Children who come from low socioeconomic backgrounds and children with learning disabilities are found to be at risk for future failure in mathematics. Even though the mathematics scores increases over time the achievement gap remains between the various ethnic and socioeconomic groups. One way to prevent this failure is to identify the students who are at risk and provide them with effective early intervention. This study reports the results of a pilot early mathematics intervention study fo...
Liber Mathematicae: A Web-Based Documentation and Collaboration Project for Mathematics
Pflaum, Markus J
2011-01-01
Traditionally, mathematical knowledge is published in printed media such as books or journals. With the advent of the Internet, a new method of publication became available. To date, however, most online mathematical publications do not employ the full capabilities of the medium. We describe a project to modernize online mathematics presentation and build a community-focused environment in which the lines between "author" and "reader" are blurred, enhancing collaboration and improving publication quality.
Liber Mathematicae: A Web-Based Documentation and Collaboration Project for Mathematics
Pflaum, Markus J.; Tuley, John
2011-01-01
Traditionally, mathematical knowledge is published in printed media such as books or journals. With the advent of the Internet, a new method of publication became available. To date, however, most online mathematical publications do not employ the full capabilities of the medium. We describe a project to modernize online mathematics presentation and build a community-focused environment in which the lines between "author" and "reader" are blurred, enhancing collaboration and improving publica...
Mathematical Thinking in Chemistry
José L. Villaveces; Guillermo Restrepo
2012-01-01
Mathematical chemistry is often thought to be a 20th-century subdiscipline of chemistry, but in this paper we discuss several early chemical ideas and some landmarks of chemistry as instances of the mathematical way of thinking; many of them before 1900. By the mathematical way of thinking, we follow Weyl's description of it in terms of functional thinking, i.e. setting up variables, symbolizing them, and seeking for functions relating them. The cases we discuss are Plato's triangles, Geoffro...
Salloum, Maher N.; Gharagozloo, Patricia E.
2013-10-01
Metal particle beds have recently become a major technique for hydrogen storage. In order to extract hydrogen from such beds, it is crucial to understand the decomposition kinetics of the metal hydride. We are interested in obtaining a a better understanding of the uranium hydride (UH3) decomposition kinetics. We first developed an empirical model by fitting data compiled from different experimental studies in the literature and quantified the uncertainty resulting from the scattered data. We found that the decomposition time range predicted by the obtained kinetics was in a good agreement with published experimental results. Secondly, we developed a physics based mathematical model to simulate the rate of hydrogen diffusion in a hydride particle during the decomposition. We used this model to simulate the decomposition of the particles for temperatures ranging from 300K to 1000K while propagating parametric uncertainty and evaluated the kinetics from the results. We compared the kinetics parameters derived from the empirical and physics based models and found that the uncertainty in the kinetics predicted by the physics based model covers the scattered experimental data. Finally, we used the physics-based kinetics parameters to simulate the effects of boundary resistances and powder morphological changes during decomposition in a continuum level model. We found that the species change within the bed occurring during the decomposition accelerates the hydrogen flow by increasing the bed permeability, while the pressure buildup and the thermal barrier forming at the wall significantly impede the hydrogen extraction.
Özcan Dülger
2014-05-01
Full Text Available Predicting Mathematics 1 course success of students is very important to prepare them before the semester. It is difficult to obtain solution because of the non-linear property of data set. Fuzzy logic is one of the common methods for the problems which involve numeric values. In fuzzy logic, it is important to determine membership functions and their parameter's values correctly. This can be done by an expert or can be learned with a data set. In this study, we aimed to predict the Mathematics 1 course success of 434 students who enrolled to Engineering Faculty of Pamukkale University in 2007-2008 academic year by using their university exam data. For this, the adaptive-network-based fuzzy inference system (ANFIS which combines the important characteristics of artificial neural network and fuzzy logic was used. In training section, nine parameters which are selected from sixteen parameters in data set with different combinations were given to the ANFIS. When an ANFIS structure with nine input parameters has at least three membership functions for each input, it will have at least 3^9 fuzzy rules. Because of this, the training part is too slow and too much memory is needed. Instead of this inefficient structure, a hierarchical method was proposed. In this method, the ANFIS is partitioned to the sub-systems. Each sub-system performs some part of input parameters and sends their result to the final ANFIS structure to obtain the overall system output. After testing with one-third of data set, two best prediction results with ratio 77.77% and 78.47% are obtained. When these results are analyzed, it is seen that 64 successful students from 85 students and 48 unsuccessful students from 59 students in Mathematics 1 course were predicted truly in the result with ratio 77.77%. Similarly, 69 successful students from 85 students, and 44 unsuccessful students from 59 students were predicted truly in the result with ratio 78.47%.
[Medicinal values and their chemical bases of Paris].
Wang, Yue-hu; Niu, Hong-mei; Zhang, Zhao-yun; Hu, Xiang-yang; Li, Heng
2015-03-01
Medicinal values and their chemical bases of Paris (Trilliaceae) are reviewed. Paris plants include 40 species and varieties. Among them, 18 ones are medicinal plants with similarity in traditional uses. Fourteen species have been studied phytochemically, which led to isolation of 207 compounds including 121 steroidal saponins. These saponins are major active constituents from Paris plants, which can explain the traditional uses of the plants to treat cancer, malignant boil, bleeding, gastritis, and so on. The similarity in medicinal uses and chemical constituents of Paris plants implies the possibility of resource substitution among these species. It is worth to further investigate Paris plants in chemical constituents, pharmacological activity, biological property, and toxicology. PMID:26087542
Chemical interaction matrix between reagents in a Purex based process
The United States Department of Energy (DOE) is the responsible entity for the disposal of the United States excess weapons grade plutonium. DOE selected a PUREX-based process to convert plutonium to low-enriched mixed oxide fuel for use in commercial nuclear power plants. To initiate this process in the United States, a Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF) is under construction and will be operated by Shaw AREVA MOX Services at the Savannah River Site. This facility will be licensed and regulated by the U.S. Nuclear Regulatory Commission (NRC). A PUREX process, similar to the one used at La Hague, France, will purify plutonium feedstock through solvent extraction. MFFF employs two major process operations to manufacture MOX fuel assemblies: (1) the Aqueous Polishing (AP) process to remove gallium and other impurities from plutonium feedstock and (2) the MOX fuel fabrication process (MP), which processes the oxides into pellets and manufactures the MOX fuel assemblies. The AP process consists of three major steps, dissolution, purification, and conversion, and is the center of the primary chemical processing. A study of process hazards controls has been initiated that will provide knowledge and protection against the chemical risks associated from mixing of reagents over the life time of the process. This paper presents a comprehensive chemical interaction matrix evaluation for the reagents used in the PUREX-based process. Chemical interaction matrix supplements the process conditions by providing a checklist of any potential inadvertent chemical reactions that may take place. It also identifies the chemical compatibility/incompatibility of the reagents if mixed by failure of operations or equipment within the process itself or mixed inadvertently by a technician in the laboratories. (authors)
Mathematical Modeling of Plant Allelopathic Hormesis Based on Ecological-Limiting-Factor Models
Liu, Yinghu; Chen, Xiaoqiu; Duan, Shunshan; Feng, Yuanjiao; An, Min
2010-01-01
Allelopathy arises from the release of chemicals by one plant species that affect other species in its vicinity, usually to their detriment. Allelopathic effects have been demonstrated to be limiting factors for species distributions and ecological processes in some natural or agricultural communities. Based on the biphasic hormetic responses of plants to allelochemicals, ecological-limiting-factor models were introduced into the An-Johnson-Lovett hormesis model to improve modelling the pheno...
A Systematic Methodology for Design of Emulsion Based Chemical Products
Mattei, Michele; Kontogeorgis, Georgios; Gani, Rafiqul
2012-01-01
A systematic methodology for emulsion based chemical product design is presented. The methodology employs a model-based product synthesis/design stage and a modelexperiment based further refinement and/or validation stage. In this paper only the first stage is presented. The methodology employs a...... employed to obtain a list of formulations that satisfy constraints representing the desired needs (target properties). Through a conceptual case study dealing with the design of a sunscreen lotion, the application of this new methodology is illustrated....
A Systematic Methodology for Design of Emulsion Based Chemical Products
Mattei, Michele; Kontogeorgis, Georgios; Gani, Rafiqul
A systematic methodology for emulsion based chemical product design is presented. The methodology employs a model-based product synthesis/design stage and a modelexperiment based further refinement and/or validation stage. In this paper only the first stage is presented. The methodology employs a...... employed to obtain a list of formulations that satisfy constraints representing the desired needs (target properties). Through a conceptual case study dealing with the design of a sunscreen lotion, the application of this new methodology is illustrated....
Ataei, Sh; Mahmud, Z.; Khalid, M. N.
2014-04-01
The students learning outcomes clarify what students should know and be able to demonstrate after completing their course. So, one of the issues on the process of teaching and learning is how to assess students' learning. This paper describes an application of the dichotomous Rasch measurement model in measuring the cognitive process of engineering students' learning of mathematics. This study provides insights into the perspective of 54 engineering students' cognitive ability in learning Calculus III based on Bloom's Taxonomy on 31 items. The results denote that some of the examination questions are either too difficult or too easy for the majority of the students. This analysis yields FIT statistics which are able to identify if there is data departure from the Rasch theoretical model. The study has identified some potential misfit items based on the measurement of ZSTD where the removal misfit item was accomplished based on the MNSQ outfit of above 1.3 or less than 0.7 logit. Therefore, it is recommended that these items be reviewed or revised to better match the range of students' ability in the respective course.
The students learning outcomes clarify what students should know and be able to demonstrate after completing their course. So, one of the issues on the process of teaching and learning is how to assess students' learning. This paper describes an application of the dichotomous Rasch measurement model in measuring the cognitive process of engineering students' learning of mathematics. This study provides insights into the perspective of 54 engineering students' cognitive ability in learning Calculus III based on Bloom's Taxonomy on 31 items. The results denote that some of the examination questions are either too difficult or too easy for the majority of the students. This analysis yields FIT statistics which are able to identify if there is data departure from the Rasch theoretical model. The study has identified some potential misfit items based on the measurement of ZSTD where the removal misfit item was accomplished based on the MNSQ outfit of above 1.3 or less than 0.7 logit. Therefore, it is recommended that these items be reviewed or revised to better match the range of students' ability in the respective course.
Shein, E. V.
2015-07-01
The formation, development, and some problems of the current physically based models of water and solute transfer are considered in this review. These models appeared about a half century ago. They were based on the basic laws of soil physics and other branches of soil science (laws of balance, transfer, diffusion, hydrodynamic dispersion, etc.) described by the corresponding equations and programs and supported by the experimental data in the form of physically based parameters. At present, one of the main problems in the development, adaptation, and application of these models is that the current and future mathematical models should rest upon the experimental support with a clear physical basis characterizing the nature of the phenomenon described. This experimental support enables creating research models, drawing conceptual conclusions, and, hence, understanding, analyzing, and managing soil processes. This is apparently possible only if the set of methods for the experimental support of models is substantiated, preferably in direct physical experiments and under field conditions close to the future model prognoses.
A "Mathematics Background Check"
Hubisz, John
2009-01-01
Early in my career someone else reported that the best indicator of success in calculus-based physics (CBP) at our school was whether students had taken mathematics in a certain region of New Brunswick. I sat down with a very longtime mathematics teacher and asked him what he thought students should know in mathematics after high school to succeed…
Action-Based Digital Tools: Mathematics Learning in 6-Year-Old Children
Dejonckheere, Peter J. N.; Desoete, Annemie; Fonck, Nathalie; Roderiguez, Dave; Six, Leen; Vermeersch, Tine; Vermeulen, Lies
2014-01-01
Introduction: In the present study we used a metaphorical representation in order to stimulate the numerical competences of six-year-olds. It was expected that when properties of physical action are used for mathematical thinking or when abstract mathematical thinking is grounded in sensorimotor processes, learning gains should be more pronounced…
Ramnarain, Umesh
2014-01-01
A major impediment to problem solving in mathematics in the great majority of South African schools is that disadvantaged students from seriously impoverished learning environments are lacking in the necessary informal mathematical knowledge to develop their own strategies for solving non-routine problems. A randomized pretest-posttest control…
Mathematical Literacy Teachers' Engagement with Contextual Tasks Based on Personal Finance
Bansilal, Sarah; Mkhwanazi, Thokozani; Mahlabela, Patisizwe
2012-01-01
This article reports on a study carried out with a group of 108 practising Mathematical Literacy (ML) teachers who participated in an Advanced Certificate in Education (ACE) programme. The purpose of the qualitative study was to identify and describe the teachers' varying levels of engagement with mathematics tools and resources. The teachers were…
Students' Perceptions of the Learning Environment and Attitudes in Game-Based Mathematics Classrooms
Afari, Ernest; Aldridge, Jill M.; Fraser, Barry J.; Khine, Myint Swe
2013-01-01
We investigated whether the introduction of games into college-level mathematics classes in the United Arab Emirates (UAE) was effective in terms of improving students' perceptions of the learning environment and their attitudes towards of mathematics. A pre-post design involved the administration of English and Arabic versions of two surveys (one…
Powell, Sarah R.
2015-01-01
Over the past two decades, changes in legislation and mathematics standards, along with the increased placement of students with disabilities in general education settings, have resulted in higher expectations for what students with disabilities will be able to know and do related to mathematics. To adequately prepare for the demands of teaching…
The Use of ICT in Kindergarten for Teaching Addition Based on Realistic Mathematics Education
Zaranis, Nicholas
2016-01-01
The purpose of this study is to investigate if information and communications technology (ICT) helps improve kindergarten students' basic mathematical achievement regarding addition. Our research compares the level of mathematical competence of the students taught using our ICT oriented learning method which specifically takes advantage of…
Applying Mathematical Concepts with Hands-On, Food-Based Science Curriculum
Roseno, Ashley T.; Carraway-Stage, Virginia G.; Hoerdeman, Callan; Díaz, Sebastián R.; Geist, Eugene; Duffrin, Melani W.
2015-01-01
This article addresses the current state of the mathematics education system in the United States and provides a possible solution to the contributing issues. As a result of lower performance in primary mathematics, American students are not acquiring the necessary quantitative literacy skills to become successful adults. This study analyzed the…
Mindfulness-based cognitive therapy to treat multiple chemical sensitivities
Skovbjerg, S; Hauge, Christian Riis; Rasmussen, Alice;
2012-01-01
of an 8-week mindfulness-based cognitive therapy program (MBCT) for adults with MCS and to evaluate possible effects on psychological distress and illness perception. The study design was a randomized clinical trial. The MBCT programme comprised 8 weekly sessions of 2½ hours. Forty-two adults were......Multiple chemical sensitivities (MCS) is a medically unexplained and socially disabling disorder characterized by negative health effects attributed to exposure to common airborne chemicals. Currently, there is no evidence-based treatment. The objectives of the study were to assess the feasibility...... screened for eligibility and 37 were included. Mean age of the participants was 51.6 years, 35 (94.6%) were female and 21 (56.8%) were unemployed. Measures of psychological distress and illness perceptions were assessed at baseline, 4 weeks, 8 weeks and at 3 months follow-up. No significant differences in...
Guided and Team-Based Learning for Chemical Information Literacy
Loo, Jeffery L.
2013-01-01
This case study recounts a process of course design, conduct, and evaluation for a single-session chemical information literacy class using guided and team-based learning. This approach incorporates active learning, worked examples, process worksheets, and POGIL elements. The instruction followed an iterative cycle of learning exercises whereby (1) the instructor introduces an information problem or task through a short presentation, (2) student teams collaboratively work through process work...
Van Eck, Richard
This study looked at the effect of contextual advisement and competition on transfer of mathematics skills in a computer-based instructional simulation game and simulation in which game participants helped their "aunt and uncle" fix up a house. Competition referred to whether or not the participant was playing against a computer character, and…
Kartashev, Alexander; Safonov, Evgeniy; Kartasheva, Marina
2011-01-01
The mathematical model describing the operation of the installation of selfcontained heating and hot water supply based on solar thermal collector with the system of accumulation of heat energy, monitoring and control of thermal conditions of building is developed. Modeling of operation of the installation in different conditions is realized.
Tandiseru, Selvi Rajuaty
2015-01-01
The problem in this research is the lack of creative thinking skills of students. One of the learning models that is expected to enhance student's creative thinking skill is the local culture-based mathematical heuristic-KR learning model (LC-BMHLM). Heuristic-KR is a learning model which was introduced by Krulik and Rudnick (1995) that is the…
Gann, Linda
2013-01-01
The research centered on secondary mathematics teachers' beliefs, attitudes, knowledge base, and practices in meeting the academic and language needs of English language learners. Using socio-cultural theory and social practice theory to frame the study, the research design employed a mixed methods approach incorporating self-reported…
Cheriani, Cheriani; Mahmud, Alimuddin; Tahmir, Suradi; Manda, Darman; Dirawan, Gufran Darma
2015-01-01
This study aims to determine the differences in learning output by using Problem Based Model combines with the "Buginese" Local Cultural Knowledge (PBL-Culture). It is also explores the students activities in learning mathematics subject by using PBL-Culture Models. This research is using Mixed Methods approach that combined quantitative…
Murni, Atma; Sabandar, Jozua; Kusumah, Yaya S.; Kartasamita, Bana Goerbana
2013-01-01
The aim of this study is to know the differences of enhancement in mathematical problem solving ability (MPSA) between the students who received soft skill- based metacognitive learning (SSML) with the students who got conventional learning (CL). This research is a quasi experimental design with pretest-postest control group. The population in…
BouJaoude, Saouma B.; Jurdak, Murad E.
2010-01-01
The purposes of this study were to understand the nature of discourse in terms of knowledge types and cognitive process, source of utterances (student or teacher), and time use in microcomputer-based labs (MBL) and verification type labs (VTL) and to gain an understanding of the role of MBL in promoting mathematization. The study was conducted in…
Tseng, Kuo-Hung; Chang, Chi-Cheng; Lou, Shi-Jer; Chen, Wen-Ping
2013-01-01
Many scholars claimed the integration of science, technology, engineering and mathematics (STEM) education is beneficial to the national economy and teachers and institutes have been working to develop integrated education programs. This study examined a project-based learning (PjBL) activity that integrated STEM using survey and interview…
Sapunov, Valentin; Dikinis, Alexandr; Voronov, Nikolai
2014-05-01
Russian Federation having giant area has low concentration of land meteorological check points. Net of monitoring is not enough for effective forecast and prediction of weather dynamics and extremely situations. Under increase of extremely situations and incidents - hurricanes et al (two times from begin of XXI century) reconstruction and "perestroika" of monitoring net is needful and necessary. The basis of such a progress is distant monitoring using planes and satellites adding land contact monitoring base on efforts of existed points and stations. Interaction of contact and distant views may make hydro meteorological data and prediction more fine and significant. Tradition physical methods must be added by new biological methods of modern study. According to gotten researches animal are able to predict extremely hazards of natural and anthropogenic nature basing of interaction between biological matter and probable physical field that is under primary study. For example it was animals which forecasted dropping of Chelyabinsk meteorite of 2013. Adding of biological indication with complex of meteorological data may increase significance of hazard prediction. The uniting of all data and approaches may become basis of proposed mathematical hydro meteorological weather models. Introduction to practice reported complex methods may decrease of loss from hydro meteorological risks and hazards and increase stability of country economics.
Problem-based learning in teaching Mathematics at the science-art centers
Ali İhsan BORAN
2008-06-01
Full Text Available It is known that approximately 5 percent of the population of a community is made up of gifted and mentally deficient people. Half of this includes the gifted and talented people. Yet, until now no due importance has been given to the education of gifted and talented people in our country. But recently this negligence has started to change with the foundation of independent special education centers, called “science and arts centers”, which specially serve to gifted students in pre-school, primary, and high school period in order to make them aware of their individual skills and use their full capacity by improving it without interrupting their formal education. These entirely new centers are facing a lot of problems, however. One of the major problems is the lack of exemplary activities to enable students to use and improve their potentials effectively. In this article, the role and importance of Problem Based Learning (PBL in teaching mathematics to gifted students is dealt with stressing its reasons and some sample Problem Based Learning (PBL activities applied in Malatya Science and Arts Center are given.
The irradiation of materials and products 'off carrier' has historically been performed using a 'drop-and-read' methodology whereby the radioisotope source is raised and lowered repeatedly until the desired absorbed dose is achieved. This approach is time consuming from both a manpower and process perspective. Static irradiation-based processes can also be costly because of the need for repeated experimental verification of target dose delivery. In our paper we address the methods used for predicting Ethicon Endo Surgery's (EES's) off-carrier absorbed dose distributions. The scenarios described herein are complex due to the fact that the on-carrier process stream exhibits a wide range of densities and dose rates. The levels of observed complexity are attributed to the 'just-in-time' production strategy and its related requirements as they apply to the programming of EES's cobalt-60 irradiators. Validation of off-carrier processing methodologies requires sophisticated parametric-based systems utilizing mathematical algorithms that predict off-carrier absorbed dose rate relative to the on-carrier process stream components. Irradiation process simulation is achieved using a point kernel computer modeling approach, coupled with database generation and maintenance. Dose prediction capabilities are validated via routine and transfer standard dosimetry
Luther, Kenneth H.
2012-01-01
Mathematical modeling of groundwater flow is a topic at the intersection of mathematics and geohydrology and is rarely encountered in undergraduate mathematics. However, this subject is full of interesting and meaningful examples of truly "applied" mathematics accessible to undergraduates, from the pre-calculus to advanced mathematics levels. This…