Mathematical techniques: A compilation
NASA Technical Reports Server (NTRS)
1975-01-01
Articles on theoretical and applied mathematics are introduced. The articles cover information that might be of interest to workers in statistics and information theory, computational aids that could be used by scientists and engineers, and mathematical techniques for design and control.
"Influence Method". Detailed mathematical description
NASA Astrophysics Data System (ADS)
Rios, I. J.; Mayer, R. E.
2015-07-01
A new method for the absolute determination of nuclear particle flux in the absence of known detector efficiency, the "Influence Method", was recently published (I.J. Rios and R.E. Mayer, Nuclear Instruments & Methods in Physics Research A 775 (2015) 99-104). The method defines an estimator for the population and another estimator for the efficiency. In this article we present a detailed mathematical description which yields the conditions for its application, the probability distributions of the estimators and their characteristic parameters. An analysis of the different cases leads to expressions of the estimators and their uncertainties.
Mathematical Optimization Techniques
NASA Technical Reports Server (NTRS)
Bellman, R. (Editor)
1963-01-01
The papers collected in this volume were presented at the Symposium on Mathematical Optimization Techniques held in the Santa Monica Civic Auditorium, Santa Monica, California, on October 18-20, 1960. The objective of the symposium was to bring together, for the purpose of mutual education, mathematicians, scientists, and engineers interested in modern optimization techniques. Some 250 persons attended. The techniques discussed included recent developments in linear, integer, convex, and dynamic programming as well as the variational processes surrounding optimal guidance, flight trajectories, statistical decisions, structural configurations, and adaptive control systems. The symposium was sponsored jointly by the University of California, with assistance from the National Science Foundation, the Office of Naval Research, the National Aeronautics and Space Administration, and The RAND Corporation, through Air Force Project RAND.
Mathematical Description of Dendrimer Structure
NASA Technical Reports Server (NTRS)
Majoros, Istvan J.; Mehta, Chandan B.; Baker, James R., Jr.
2004-01-01
Characteristics of starburst dendrimers can be easily attributed to the multiplicity of the monomers used to synthesize them. The molecular weight, degree of polymerization, number of terminal groups and branch points for each generation of a dendrimer can be calculated using mathematical formulas incorporating these variables. Mathematical models for the calculation of degree of polymerization, molecular weight, and number of terminal groups and branching groups previously published were revised and elaborated on for poly(amidoamine) (PAMAM) dendrimers, and introduced for poly(propyleneimine) (POPAM) dendrimers and the novel POPAM-PAMAM hybrid, which we call the POMAM dendrimer. Experimental verification of the relationship between theoretical and actual structure for the PAMAM dendrimer was also established.
Towards a Mathematical Description of Biodiversity Evolution
NASA Astrophysics Data System (ADS)
Horvath, Jorge E.
2014-09-01
We outline in this work a mathematical description of biodiversity evolution based on a second-order differential equation (also known as the "inertial/Galilean view"). After discussing the motivations and explicit forms of the simplest "forces", we are lead to an equation analogue to a harmonic oscillator. The known solutions for the homogeneous problem are then tentatively related to the biodiversity curves of Sepkoski and Alroy et al., suggesting mostly an inertial behavior of the time evolution of the number of genera and a quadratic behavior in some long-term evolution after extinction events. We present the Green function for the dynamical system and apply it to the description of the recovery curve after the Permo-Triassic extinction, as recently analyzed by Burgess, Bowring and Shen. Even though the agreement is not satisfactory, we point out direct connections between observed drop times after massive extinctions and mathematical constants and discuss why the failure ensues, suggesting a more complex form of the second-order mathematical description.
Practice; criteria; provisions; mathematical descriptions: Examples
NASA Astrophysics Data System (ADS)
Wijdieks, J.
1983-06-01
Waterhammer is defined as the appearance of pressure changes in closed conduits caused by velocity changes with time of the flow. Therefore waterhammer may occur in all kinds of pipelines in which flow changes occur over time: long or short pipelines for oil, sewage, drinking water, cooling water, slurry, coal slurry, chemicals, and in fresh water or city heating networks. The phenomenon of waterhammer is discussed herein. Specific parameters addressed include: the practical causes of waterhammer, cavitation flow, overpressure, vapor pressures, bulk modulus, continuous and discontinuous flow, and provisions to prevent waterhammer. Calculation of waterhammer is presented along with a mathematical description thereof. Hydraulic equipment (valves, pumps, surge towers) is also discussed.
Mathematical Description of Bacterial Traveling Pulses
Bournaveas, Nikolaos; Buguin, Axel; Silberzan, Pascal; Perthame, Benoît
2010-01-01
The Keller-Segel system has been widely proposed as a model for bacterial waves driven by chemotactic processes. Current experiments on Escherichia coli have shown the precise structure of traveling pulses. We present here an alternative mathematical description of traveling pulses at the macroscopic scale. This modeling task is complemented with numerical simulations in accordance with the experimental observations. Our model is derived from an accurate kinetic description of the mesoscopic run-and-tumble process performed by bacteria. This can account for recent experimental observations with E. coli. Qualitative agreements include the asymmetry of the pulse and transition in the collective behaviour (clustered motion versus dispersion). In addition, we can capture quantitatively the traveling speed of the pulse as well as its characteristic length. This work opens several experimental and theoretical perspectives since coefficients at the macroscopic level are derived from considerations at the cellular scale. For instance, the particular response of a single cell to chemical cues turns out to have a strong effect on collective motion. Furthermore, the bottom-up scaling allows us to perform preliminary mathematical analysis and write efficient numerical schemes. This model is intended as a predictive tool for the investigation of bacterial collective motion. PMID:20808878
Secondary Students' Descriptions of "Good" Mathematics Teachers
ERIC Educational Resources Information Center
Murray, Sara
2011-01-01
There are many recent studies which have explored the notion of high quality or effective mathematics teaching but relatively few have sought the views of students. Student perspectives regarding effective teaching are important for many reasons, and are arguably particularly significant in mathematics given the international trends of declining…
Preferences of Teaching Methods and Techniques in Mathematics with Reasons
ERIC Educational Resources Information Center
Ünal, Menderes
2017-01-01
In this descriptive study, the goal was to determine teachers' preferred pedagogical methods and techniques in mathematics. Qualitative research methods were employed, primarily case studies. 40 teachers were randomly chosen from various secondary schools in Kirsehir during the 2015-2016 educational terms, and data were gathered via…
Connecting Intonation Labels to Mathematical Descriptions of Fundamental Frequency
ERIC Educational Resources Information Center
Grabe, Esther; Kochanski, Greg; Coleman, John
2007-01-01
The mathematical models of intonation used in speech technology are often inaccessible to linguists. By the same token, phonological descriptions of intonation are rarely used by speech technologists, as they cannot be implemented directly in applications. Consequently, these research communities do not benefit much from each other's insights. In…
Towards a Bernsteinian Language of Description for Mathematics Classroom Discourse
ERIC Educational Resources Information Center
Straehler-Pohl, Hauke; Gellert, Uwe
2013-01-01
This article aims at developing an external language of description to investigate the problem of why particular groups of students are systematically not provided access to school mathematical knowledge. Based on Basil Bernstein's conceptualisation of power in classification, we develop a three-dimensional model that operationalises the…
Towards a Bernsteinian Language of Description for Mathematics Classroom Discourse
ERIC Educational Resources Information Center
Straehler-Pohl, Hauke; Gellert, Uwe
2013-01-01
This article aims at developing an external language of description to investigate the problem of why particular groups of students are systematically not provided access to school mathematical knowledge. Based on Basil Bernstein's conceptualisation of power in classification, we develop a three-dimensional model that operationalises the…
NASA Technical Reports Server (NTRS)
Lennington, R. K.; Rassbach, M. E.
1979-01-01
Discussed in this report is the clustering algorithm CLASSY, including detailed descriptions of its general structure and mathematical background and of the various major subroutines. The report provides a development of the logic and equations used with specific reference to program variables. Some comments on timing and proposed optimization techniques are included.
Fuzzy mathematical techniques with applications
Kandel, A.
1986-01-01
This text presents the basic concepts of fuzzy set theory within a context of real-world applications. The book is self-contained and can be used as a starting point for people interested in this fast growing field as well as by researchers looking for new application techniques. The section on applications includes: Manipulation of knowledge in expert systems; relational database structures; pattern clustering; analysis of transient behavior in digital systems; modeling of uncertainty and search trees. Contents: Fuzzy sets; Possibility theory and fuzzy quantification; Fuzzy functions; Fuzzy events and fuzzy statistics; Fuzzy relations; Fuzzy logics; Some applications; Bibliography.
A description of seismic amplitude techniques
NASA Astrophysics Data System (ADS)
Shadlow, James
2014-02-01
The acquisition of seismic data is a non-invasive technique used for determining the sub surface geology. Changes in lithology and fluid fill affect the seismic wavelet. Analysing seismic data for direct hydrocarbon indicators (DHIs), such as full stack amplitude anomalies, or amplitude variation with offset (AVO), can help a seismic interpreter relate the geophysical response to real geology and, more importantly, to distinguish the presence of hydrocarbons. Inversion is another commonly used technique that attempts to tie the seismic data back to the geology. Much has been written about these techniques, and attempting to gain an understanding on the theory and application of them by reading through various journals can be quite daunting. The purpose of this paper is to briefly outline DHI analysis, including full stack amplitude anomalies, AVO and inversion and show the relationship between all three. The equations presented have been included for completeness, but the reader can pass over the mathematical detail.
THE SHEFFIELD ALCOHOL POLICY MODEL - A MATHEMATICAL DESCRIPTION.
Brennan, Alan; Meier, Petra; Purshouse, Robin; Rafia, Rachid; Meng, Yang; Hill-Macmanus, Daniel; Angus, Colin; Holmes, John
2014-09-30
This methodology paper sets out a mathematical description of the Sheffield Alcohol Policy Model version 2.0, a model to evaluate public health strategies for alcohol harm reduction in the UK. Policies that can be appraised include a minimum price per unit of alcohol, restrictions on price discounting, and broader public health measures. The model estimates the impact on consumers, health services, crime, employers, retailers and government tax revenues. The synthesis of public and commercial data sources to inform the model structure is described. A detailed algebraic description of the model is provided. This involves quantifying baseline levels of alcohol purchasing and consumption by age and gender subgroups, estimating the impact of policies on consumption, for example, using evidence on price elasticities of demand for alcohol, quantification of risk functions relating alcohol consumption to harms including 47 health conditions, crimes, absenteeism and unemployment, and finally monetary valuation of the consequences. The results framework, shown for a minimum price per unit of alcohol, has been used to provide policy appraisals for the UK government policy-makers. In discussion and online appendix, we explore issues around valuation and scope, limitations of evidence/data, how the framework can be adapted to other countries and decisions, and ongoing plans for further development. © 2014 The Authors. Health Economics published by John Wiley & Sons Ltd. © 2014 The Authors. Health Economics published by John Wiley & Sons Ltd.
Researchers' Descriptions and the Construction of Mathematical Thinking
ERIC Educational Resources Information Center
Barwell, Richard
2009-01-01
Research in mathematics education is a discursive process: It entails the analysis and production of texts, whether in the analysis of what learners say, the use of transcripts, or the publication of research reports. Much research in mathematics education is concerned with various aspects of mathematical thinking, including mathematical knowing,…
Kiss, Virág; Lehoczki, Gábor; Ősz, Katalin
2017-04-12
Substituted 1,4-benzoquinone (QR) derivatives are photosensitive in aqueous solution and form hydroquinones (QR-H2) and hydroxy-quinones (QR-OH), two weak acids in their photoreaction. For this reason, the kinetics of the photoreaction can be conveniently followed by the pH-stat titration technique. The mathematical description of the kinetic traces measured provides the two main parameters of the photoreaction: the differential quantum yield of the reaction (Φ) and the ratio of the two photo-products, i.e. the fraction of QR that is converted to QR-OH (α). These values are described in this paper for 2,5-dichloro-1,4-benzoquinone at different pH values, together with the detailed mathematical evaluation of the application limits of the pH-stat method for such reactions.
Mathematical and Numerical Techniques in Energy and Environmental Modeling
NASA Astrophysics Data System (ADS)
Chen, Z.; Ewing, R. E.
Mathematical models have been widely used to predict, understand, and optimize many complex physical processes, from semiconductor or pharmaceutical design to large-scale applications such as global weather models to astrophysics. In particular, simulation of environmental effects of air pollution is extensive. Here we address the need for using similar models to understand the fate and transport of groundwater contaminants and to design in situ remediation strategies. Three basic problem areas need to be addressed in the modeling and simulation of the flow of groundwater contamination. First, one obtains an effective model to describe the complex fluid/fluid and fluid/rock interactions that control the transport of contaminants in groundwater. This includes the problem of obtaining accurate reservoir descriptions at various length scales and modeling the effects of this heterogeneity in the reservoir simulators. Next, one develops accurate discretization techniques that retain the important physical properties of the continuous models. Finally, one develops efficient numerical solution algorithms that utilize the potential of the emerging computing architectures. We will discuss recent advances and describe the contribution of each of the papers in this book in these three areas. Keywords: reservoir simulation, mathematical models, partial differential equations, numerical algorithms
Short description of mathematical support programs for space experiments in the Interkosmos program
NASA Technical Reports Server (NTRS)
Elyasberg, P. Y.
1979-01-01
A synopsis of programs of mathematical support designed at the Institute for Cosmic Research of the USSR Academy of Sciences for cosmic experiments being conducted in the Interkosmos Program is presented. A short description of the appropriate algorithm is given.
Descriptions of Free and Freeware Software in the Mathematics Teaching
NASA Astrophysics Data System (ADS)
Antunes de Macedo, Josue; Neves de Almeida, Samara; Voelzke, Marcos Rincon
2016-05-01
This paper presents the analysis and the cataloging of free and freeware mathematical software available on the internet, a brief explanation of them, and types of licenses for use in teaching and learning. The methodology is based on the qualitative research. Among the different types of software found, it stands out in algebra, the Winmat, that works with linear algebra, matrices and linear systems. In geometry, the GeoGebra, which can be used in the study of functions, plan and spatial geometry, algebra and calculus. For graphing, can quote the Graph and Graphequation. With Graphmatica software, it is possible to build various graphs of mathematical equations on the same screen, representing cartesian equations, inequalities, parametric among other functions. The Winplot allows the user to build graphics in two and three dimensions functions and mathematical equations. Thus, this work aims to present the teachers some free math software able to be used in the classroom.
Kim, David; Farthing, Matthew W.; Miller, Cass T.; Nylander-French, Leena A.
2008-01-01
The objective of this research was to develop a mathematical description of uptake of aromatic and aliphatic hydrocarbons into the stratum corneum of human skin in vivo. A simple description based on Fick’s Laws of diffusion was used to predict the spatiotemporal variation of naphthalene, 1- and 2-methylnaphthalene, undecane, and dodecane in the stratum corneum of human volunteers. The estimated values of the diffusion coefficients for each chemical were comparable to values predicted using in vitro skin systems and biomonitoring studies. These results demonstrate the value of measuring dermal exposure using the tape-strip technique and the importance of quantifying of dermal uptake. PMID:18423910
Mathematical Descriptions of Biochemical Networks: Stability, Stochasticity, Evolution
Rosenfeld, Simon
2011-01-01
In this paper, we review some fundamental aspects, as well as some new developments, in the emerging field of network biology. The focus of attention is placed on mathematical approaches to conceptual modeling of biomolecular networks with special emphasis on dynamic stability, stochasticity and evolution. PMID:21419158
Tailoring Modified Moore Method Techniques to Liberal Arts Mathematics Courses
ERIC Educational Resources Information Center
Hitchman, Theron J.; Shaw, Douglas
2015-01-01
Inquiry-based learning (IBL) techniques can be used in mathematics courses for non-majors, such as courses required for liberal arts majors to fulfill graduation requirements. Unique challenges are discussed, followed by adaptations of IBL techniques to overcome those challenges.
Tailoring Modified Moore Method Techniques to Liberal Arts Mathematics Courses
ERIC Educational Resources Information Center
Hitchman, Theron J.; Shaw, Douglas
2015-01-01
Inquiry-based learning (IBL) techniques can be used in mathematics courses for non-majors, such as courses required for liberal arts majors to fulfill graduation requirements. Unique challenges are discussed, followed by adaptations of IBL techniques to overcome those challenges.
Social media enhances languages differentiation: a mathematical description.
Vidal-Franco, Ignacio; Guiu-Souto, Jacobo; Muñuzuri, Alberto P
2017-05-01
Understanding and predicting the evolution of competing languages is a topic of high interest in a world with more than 6000 languages competing in a highly connected environment. We consider a reasonable mathematical model describing a situation of competition between two languages and analyse the effect of the speakers' connectivity (i.e. social networks). Surprisingly, instead of homogenizing the system, a high degree of connectivity helps to introduce differentiation for the appropriate parameters.
Problems of the mathematical description of rocket engines as plants
NASA Astrophysics Data System (ADS)
Kiforenko, B. N.
2012-09-01
Mathematical models of liquid-propellant, nuclear, and electric rocket engines are presented that more fully describe thrust generation than the classical models do. The optimal control of engine thrust is analyzed within the framework of Mayer's general variational problem. It is shown that the control of a rocket engine satisfying the necessary optimality conditions belongs to the boundary arc of the feasible control set between the point of maximum thrust and the point of maximum exhaust velocity
Mathematical description of human body constitution and fatness.
Sheikh-Zade, Yu R; Galenko-Yaroshevskii, P A; Cherednik, I L
2014-02-01
Using mathematical modeling of human body, we demonstrated logical drawbacks of body mass index (BMI1 = M/H(2); A. Quetelet, 1832) and proposed more precise body mass index (BMI2 = M/H(3)) as well as body constitution index (BCI = (M/H(3))(1/2)) and fatness index (FI = M/HC(2)), where M, H, and C are body weight, height, and wrist circumference of the individual.
Multiscale mapping: Physical concepts and mathematical techniques
USDA-ARS?s Scientific Manuscript database
This is an introductory summary for papers either invited or a part of a symposium at the 18th World Congress of Soil Science, July 2006 in Philadelphia. The symposium, titled "Multiscale Mapping of Soil Properties for Environmental Studies, Agriculture, and Decision Making," focused on techniques u...
Descriptive Statistical Techniques for Librarians. 2nd Edition.
ERIC Educational Resources Information Center
Hafner, Arthur W.
A thorough understanding of the uses and applications of statistical techniques is integral in gaining support for library funding or new initiatives. This resource is designed to help practitioners develop and manipulate descriptive statistical information in evaluating library services, tracking and controlling limited resources, and analyzing…
A mathematical description of glitches in neutron stars
NASA Astrophysics Data System (ADS)
Mongiovì, Maria Stella; Russo, Francesco G.; Sciacca, Michele
2017-08-01
In a pulsar, there are gaps and difficulties in our knowledge of glitches, mainly because of the absence of information about the physics of the matter of the star. This has motivated several authors to suggest dynamical models that interpret most of the astronomical data. Many predictions are based on the assumption that the inner part is analogous to the structure of matter of superfluids. Here, we illustrate a new mathematical model, partially inspired by the dynamics of superfluid helium. We obtain two evolution equations for the angular velocities (of the crust and of superfluid), which are supported by another evolution equation for the average vortex line length per unit volume. This third equation is more delicate from an analytical perspective and is probably at the origin of glitches. We identify two stationary solutions, corresponding to the straight vortex regime and the turbulent regime.
Description of a tilt wing mathematical model for piloted simulation
NASA Technical Reports Server (NTRS)
Totah, Joseph J.
1991-01-01
A tilt-wing mathematical model that was used in a piloted six-deg-of-freedom flight simulation application is presented. Two types of control systems developed for the model - a conventional programmed-flap wing-tilt control system and a geared-flap wing-tilt control system - are discussed. The objective of this effort was to develop the capability to study tilt-wing aircraft. Experienced tilt-wing pilots subjectively evaluated the model using programmed-flap control to assess the quality of the simulation. The objective was met and the model was then applied to study geared-flap control to investigate the possibility of eliminating the need for auxiliary pitch control devices. This was performed in the moving-base simulation environment, and the vehicle responses with programmed-flap and geared-flap control were compared.
Research on Mathematical Techniques in Psychology. Final Report.
ERIC Educational Resources Information Center
Gulliksen, Harold
Mathematical techniques are developed for studying psychological problems in three fields: (1) psychological scaling, (2) learning and concept formation, and (3) mental measurement. Psychological scaling procedures are demonstrated to be useful in many areas, ranging from sensory discrimination of physical stimuli, such as colors, sounds, etc.,…
Reliability of Identification of Behavior Change Techniques in Intervention Descriptions.
Abraham, Charles; Wood, Caroline E; Johnston, Marie; Francis, Jill; Hardeman, Wendy; Richardson, Michelle; Michie, Susan
2015-12-01
The aim of this paper is to assess the frequency of identification as well as the inter-coder and test-retest reliability of identification of behavior change techniques (BCTs) in written intervention descriptions. Forty trained coders applied the "Behavior Change Technique Taxonomy version 1" (BCTTv1) to 40 intervention descriptions published in protocols and repeated this 1 month later. Eighty of 93 defined BCTs were identified by at least one trained coder, and 22 BCTs were identified in 16 (40 %) or more of 40 descriptions. Good inter-coder reliability was observed across 80 BCTs identified in the protocols: 66 (80 %) achieved mean prevalence and bias-adjusted kappa (PABAK) scores of 0.70 or greater, and 59 (74 %) achieved mean scores of 0.80 or greater. There was good within-coder agreement between baseline and 1 month, demonstrating good test-retest reliability. BCTTv1 can be used by trained coders to identify BCTs in intervention descriptions reliably. However, some frequently occurring BCT definitions require further clarification.
Deadline rush: a time management phenomenon and its mathematical description.
König, Cornelius J; Kleinmann, Martin
2005-01-01
A typical time management phenomenon is the rush before a deadline. Behavioral decision making research can be used to predict how behavior changes before a deadline. People are likely not to work on a project with a deadline in the far future because they generally discount future outcomes. Only when the deadline is close are people likely to work. On the basis of recent intertemporal choice experiments, the authors argue that a hyperbolic function should provide a more accurate description of the deadline rush than an exponential function predicted by an economic model of discounted utility. To show this, the fit of the hyperbolic and the exponential function were compared with data sets that describe when students study for exams. As predicted, the hyperbolic function fit the data significantly better than the exponential function. The implication for time management decisions is that they are most likely to be inconsistent over time (i.e., people make a plan how to use their time but do not follow it).
NASA Astrophysics Data System (ADS)
Gurova, E. G.
2017-07-01
In this article a mathematical description of the block diagram of the vibration isolation device with stiffness compensator is given. The vibration isolation system simulation performed with different functional elements, during which operation waveforms obtained with neodymium device compensator of the stiffness. Research & Development is under the scholarship of the President of Russian Federation, order No 184 from 10th of March 2015.
ERIC Educational Resources Information Center
Chinelo, Okigbo Ebele; Nwanneka, Okoli Josephine
2016-01-01
This study investigated the techniques used by secondary school Science Technology and Mathematics (STM) teachers in controlling undesirable behaviours in their classrooms. It adopted descriptive survey design in which 178 Anambra State teachers teaching STM subjects in senior secondary were involved in the research. Two sections of questionnaire…
ERIC Educational Resources Information Center
Badru, Ademola K.
2015-01-01
This study examined the prediction of academic success of Junior secondary school mathematics students using their cognitive style and problem solving technique. A descriptive survey of correlation type was adopted for this study. A purposive sampling procedure was used to select five Public Junior secondary schools in Ijebu-Ode local government…
Mathematical analysis techniques for modeling the space network activities
NASA Technical Reports Server (NTRS)
Foster, Lisa M.
1992-01-01
The objective of the present work was to explore and identify mathematical analysis techniques, and in particular, the use of linear programming. This topic was then applied to the Tracking and Data Relay Satellite System (TDRSS) in order to understand the space network better. Finally, a small scale version of the system was modeled, variables were identified, data was gathered, and comparisons were made between actual and theoretical data.
Innovative techniques for the description of reservoir heterogeneity using tracers
Pope, G.; Sepehrnoori, K.
1991-09-01
The objective of this research is to develop an advanced, innovative technique for the description of reservoir heterogeneity. This proposed method consists of using tracers in single-well backflow tests. The general idea is to make use of fluid drift in the reservoir either due to naturally occurring pressure gradients in the reservoir, or by deliberately imposed pressure gradients using adjacent injection and production wells in the same reservoir. The analytical tool that will be used to design and interpret these tests is a compositional reservoir simulator with special features added and tested specifically for this purpose. 2 refs., 5 figs.
Quantitative description of the morphology of the human palate by a mathematical equation.
Ferrario, V F; Sforza, C; Schmitz, J H; Colombo, A
1998-09-01
To derive a three-dimensional mathematical description of normal human hard tissue palatal size and shape. The maxillary dental casts of 30 adolescents free from respiratory problems, who had a complete (28 teeth) permanent sound dentition with normal occlusion, were studied. The x, y, z coordinates of several standardized palatal and dental landmarks were obtained with a computerized three-dimensional digitizer. Palatal landmarks were used to derive a mathematical equation of palatal shape in the frontal and sagittal planes. Palatal width, length, frontal and sagittal heights, and sagittal slope, as well as dental arch transverse and anteroposterior dimensions, were computed. Neither the size nor the shape of the palate was significantly influenced by gender. Only the intercanine distance was larger (p < .025) in males than in females. Data collected in the present investigation could represent a first database for the quantitative description of normal human palatal morphology in subjects with a complete permanent dentition.
Physical and Mathematical Description of Nuclear Weapons Identification System (NWIS) Signatures
Mattingly, J.K.; Mihalczo, J.T.; Mullens, J.A.; Valentine, T.E.
1997-09-26
This report describes all time and frequency analysis parameters measured with the new Nuclear Weapons Identification System (NWIS) processor with three input channels: (1) the 252Cf source ionization chamber (2) a detection channel; and (3) a second detection channel for active measurements. An intuitive and physical description of the various functions is given as well as a brief mathematical description and a brief description of how the data are acquired. If the fill five channel capability is used, the number of functions increases in number but not in type. The parameters provided by this new NWIS processor can be divided into two general classes: time analysis signatures including multiplicities and frequency analysis signatures. Data from measurements with an 18.75 kg highly enriched uranium (93.2 wt 0/0, 235U) metai casting for storage are presented to illustrate the various time and frequency analysis parameters.
Physical and mathematical description of Nuclear Weapons Identification System (NWIS) signatures
Mihalczo, J.T.; Valentine, T.E.; Mullens, J.A.; Mattingly, J.K.
1997-09-26
This report describes all time and frequency analysis parameters measured with the new Nuclear Weapons Identification System (NWIS) processor with three input channels: (1) the {sup 252}Cf source ionization chamber; (2) a detection channel; and (3) a second detection channel for active measurements. An intuitive and physical description of the various functions is given as well as a brief mathematical description and a brief description of how the data are acquired. If the full five channel capability is used, the number of functions increases in number but not in type. The parameters provided by this new NWIS processor can be divided into two general classes: time analysis signatures including multiplicities and frequency analysis signatures. Data from measurements with an 18.75 kg highly enriched uranium (93.2 wt%, {sup 235}U) metal casting for storage are presented to illustrate the various time and frequency analysis parameters.
ERIC Educational Resources Information Center
Petras, Carol-Lynn M.
2010-01-01
This descriptive study was conducted because there is a lack of information regarding the pedagogical orientation associated with Information and Communication Technology, ICT, use in United States mathematics and science classrooms. Eighth grade science and mathematics teachers' pedagogical orientations, their use ICT when teaching and how ICT…
ERIC Educational Resources Information Center
Petras, Carol-Lynn M.
2010-01-01
This descriptive study was conducted because there is a lack of information regarding the pedagogical orientation associated with Information and Communication Technology, ICT, use in United States mathematics and science classrooms. Eighth grade science and mathematics teachers' pedagogical orientations, their use ICT when teaching and how ICT…
Panov, Vladimir G; Katsnelson, Boris A; Varaksin, Anatoly N; Privalova, Larisa I; Kireyeva, Ekaterina P; Sutunkova, Marina P; Valamina, Irene E; Beresneva, Olga Yu
2015-01-01
In this article, we check and develop further some postulates of the theory and mathematical modeling of combined toxic effect that we proposed earlier [1]. To this end, we have analyzed the results of an experiment on rats exposed during 6 weeks to repeated intraperitoneal injections of lead acetate, sodium fluoride or both. The development of intoxication was estimated quantitatively with 54 functional, biochemical and morphometric indices. For mathematical description of the effect that lead and fluorine doses produced alone or in combination, we used a response surface regression model containing linear and cross terms (hyperbolic paraboloid). It is shown that the combination of lead and fluoride features the same 10 types of combined effect that we found previously for the lead and cadmium combination. Special attention is given to indices on which lead and fluorine produce an opposite effect.
Classical Mathematical Models for Description and Prediction of Experimental Tumor Growth
Benzekry, Sébastien; Lamont, Clare; Beheshti, Afshin; Tracz, Amanda; Ebos, John M. L.; Hlatky, Lynn; Hahnfeldt, Philip
2014-01-01
Despite internal complexity, tumor growth kinetics follow relatively simple laws that can be expressed as mathematical models. To explore this further, quantitative analysis of the most classical of these were performed. The models were assessed against data from two in vivo experimental systems: an ectopic syngeneic tumor (Lewis lung carcinoma) and an orthotopically xenografted human breast carcinoma. The goals were threefold: 1) to determine a statistical model for description of the measurement error, 2) to establish the descriptive power of each model, using several goodness-of-fit metrics and a study of parametric identifiability, and 3) to assess the models' ability to forecast future tumor growth. The models included in the study comprised the exponential, exponential-linear, power law, Gompertz, logistic, generalized logistic, von Bertalanffy and a model with dynamic carrying capacity. For the breast data, the dynamics were best captured by the Gompertz and exponential-linear models. The latter also exhibited the highest predictive power, with excellent prediction scores (≥80%) extending out as far as 12 days in the future. For the lung data, the Gompertz and power law models provided the most parsimonious and parametrically identifiable description. However, not one of the models was able to achieve a substantial prediction rate (≥70%) beyond the next day data point. In this context, adjunction of a priori information on the parameter distribution led to considerable improvement. For instance, forecast success rates went from 14.9% to 62.7% when using the power law model to predict the full future tumor growth curves, using just three data points. These results not only have important implications for biological theories of tumor growth and the use of mathematical modeling in preclinical anti-cancer drug investigations, but also may assist in defining how mathematical models could serve as potential prognostic tools in the clinic. PMID:25167199
Mathematical Morphology Techniques For Image Processing Applications In Biomedical Imaging
NASA Astrophysics Data System (ADS)
Bartoo, Grace T.; Kim, Yongmin; Haralick, Robert M.; Nochlin, David; Sumi, Shuzo M.
1988-06-01
Mathematical morphology operations allow object identification based on shape and are useful for grouping a cluster of small objects into one object. Because of these capabilities, we have implemented and evaluated this technique for our study of Alzheimer's disease. The microscopic hallmark of Alzheimer's disease is the presence of brain lesions known as neurofibrillary tangles and senile plaques. These lesions have distinct shapes compared to normal brain tissue. Neurofibrillary tangles appear as flame-shaped structures, whereas senile plaques appear as circular clusters of small objects. In order to quantitatively analyze the distribution of these lesions, we have developed and applied the tools of mathematical morphology on the Pixar Image Computer. As a preliminary test of the accuracy of the automatic detection algorithm, a study comparing computer and human detection of senile plaques was performed by evaluating 50 images from 5 different patients. The results of this comparison demonstrates that the computer counts correlate very well with the human counts (correlation coefficient = .81). Now that the basic algorithm has been shown to work, optimization of the software will be performed to improve its speed. Also future improvements such as local adaptive thresholding will be made to the image analysis routine to further improve the systems accuracy.
Sound Blending of Techniques in Mathematics and Physics (abstract)
NASA Astrophysics Data System (ADS)
Malmini, Ranasinghe
2009-04-01
This paper discusses methods that can be used to inspire physics students to learn advanced differential equations. Numerous problems in physics are described by this type of equation. There has been rapid advancement in computer technology and development of computational mathematics-a branch of mathematics using computers to generate solutions to advanced differential equations. Arguably, this branch of mathematics is becoming more important to physicists than traditional analytical mathematics. Computer Algebra Software (CAS) packages have also emerged as a means to perform elaborate and complicated analytical mathematics much faster than possible by humans.
Mathematical Inversion of Lightning Data: Techniques and Applications
NASA Technical Reports Server (NTRS)
Koshak, William
2003-01-01
A survey of some interesting mathematical inversion studies dealing with radio, optical, and electrostatic measurements of lightning are presented. A discussion of why NASA is interested in lightning, what specific physical properties of lightning are retrieved, and what mathematical techniques are used to perform the retrievals are discussed. In particular, a relatively new multi-station VHF time-of-arrival (TOA) antenna network is now on-line in Northern Alabama and will be discussed. The network, called the Lightning Mapping Array (LMA), employs GPS timing and detects VHF radiation from discrete segments (effectively point emitters) that comprise the channel of lightning strokes within cloud and ground flashes. The LMA supports on-going ground-validation activities of the low Earth orbiting Lightning Imaging Sensor (LIS) satellite developed at NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama. The LMA also provides detailed studies of the distribution and evolution of thunderstorms and lightning in the Tennessee Valley, and offers interesting comparisons with other meteorological/geophysical datasets. In order to take full advantage of these benefits, it is essential that the LMA channel mapping accuracy (in both space and time) be fully characterized and optimized. A new channel mapping retrieval algorithm is introduced for this purpose. To characterize the spatial distribution of retrieval errors, the algorithm has been applied to analyze literally tens of millions of computer-simulated lightning VHF point sources that have been placed at various ranges, azimuths, and altitudes relative to the LMA network. Statistical results are conveniently summarized in high-resolution, color-coded, error maps.
Mathematical Inversion of Lightning Data: Techniques and Applications
NASA Technical Reports Server (NTRS)
Koshak, William
2003-01-01
A survey of some interesting mathematical inversion studies dealing with radio, optical, and electrostatic measurements of lightning are presented. A discussion of why NASA is interested in lightning, what specific physical properties of lightning are retrieved, and what mathematical techniques are used to perform the retrievals are discussed. In particular, a relatively new multi-station VHF time-of-arrival (TOA) antenna network is now on-line in Northern Alabama and will be discussed. The network, called the Lightning Mapping Array (LMA), employs GPS timing and detects VHF radiation from discrete segments (effectively point emitters) that comprise the channel of lightning strokes within cloud and ground flashes. The LMA supports on-going ground-validation activities of the low Earth orbiting Lightning Imaging Sensor (LIS) satellite developed at NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama. The LMA also provides detailed studies of the distribution and evolution of thunderstorms and lightning in the Tennessee Valley, and offers interesting comparisons with other meteorological/geophysical datasets. In order to take full advantage of these benefits, it is essential that the LMA channel mapping accuracy (in both space and time) be fully characterized and optimized. A new channel mapping retrieval algorithm is introduced for this purpose. To characterize the spatial distribution of retrieval errors, the algorithm has been applied to analyze literally tens of millions of computer-simulated lightning VHF point sources that have been placed at various ranges, azimuths, and altitudes relative to the LMA network. Statistical results are conveniently summarized in high-resolution, color-coded, error maps.
A Technique for Studying the Organization of Mathematics Text Materials. Final Report.
ERIC Educational Resources Information Center
Kane, Robert B.; Holz, Alan W.
The validity and the reliability of a technique for identifying and studying presentation variables in mathematics texts were investigated in this study. A category system for classifying messages in mathematics texts in terms of mathematical content and processes and in terms of mode of representation, procedures for applying this system to…
Kalugina, A V; Komarova, L N; Petin, V G
2002-01-01
For mathematical description of synergetic interaction of high environmental temperature and microwaves for animal heating, a simple semi-empirical model was used. In the model, it is suggested that the mechanism of synergistic interaction is caused by the additional effective damages resulting in more higher body temperature increment comparing with that expected for the independent action of each agents. These additional damages are supposed to be produced by the interaction of sublesions induces by each agent and which are ineffective for their separate action. Utilizing the results published for rabbits [15], it was demonstrated that the model describes experimental data, predicts the highest synergistic effect and the condition under which it can be achieved. The data obtained may be useful for the assessment of microwave exposure safe levels.
Description and Application of a Mathematical Method for the Analysis of Harmony
Zuo, Qiting; Jin, Runfang; Ma, Junxia
2015-01-01
Harmony issues are widespread in human society and nature. To analyze these issues, harmony theory has been proposed as the main theoretical approach for the study of interpersonal relationships and relationships between humans and nature. Therefore, it is of great importance to study harmony theory. After briefly introducing the basic concepts of harmony theory, this paper expounds the five elements that are essential for the quantitative description of harmony issues in water resources management: harmony participant, harmony objective, harmony regulation, harmony factor, and harmony action. A basic mathematical equation for the harmony degree, that is, a quantitative expression of harmony issues, is introduced in the paper: HD = ai − bj, where a is the uniform degree, b is the difference degree, i is the harmony coefficient, and j is the disharmony coefficient. This paper also discusses harmony assessment and harmony regulation and introduces some application examples. PMID:26167535
Description and Application of a Mathematical Method for the Analysis of Harmony.
Zuo, Qiting; Jin, Runfang; Ma, Junxia; Cui, Guotao
2015-01-01
Harmony issues are widespread in human society and nature. To analyze these issues, harmony theory has been proposed as the main theoretical approach for the study of interpersonal relationships and relationships between humans and nature. Therefore, it is of great importance to study harmony theory. After briefly introducing the basic concepts of harmony theory, this paper expounds the five elements that are essential for the quantitative description of harmony issues in water resources management: harmony participant, harmony objective, harmony regulation, harmony factor, and harmony action. A basic mathematical equation for the harmony degree, that is, a quantitative expression of harmony issues, is introduced in the paper: HD = ai - bj, where a is the uniform degree, b is the difference degree, i is the harmony coefficient, and j is the disharmony coefficient. This paper also discusses harmony assessment and harmony regulation and introduces some application examples.
Computational Technique for Teaching Mathematics (CTTM): Visualizing the Polynomial's Resultant
ERIC Educational Resources Information Center
Alves, Francisco Regis Vieira
2015-01-01
We find several applications of the Dynamic System Geogebra--DSG related predominantly to the basic mathematical concepts at the context of the learning and teaching in Brasil. However, all these works were developed in the basic level of Mathematics. On the other hand, we discuss and explore, with DSG's help, some applications of the polynomial's…
Descriptive Feedback; Increasing Teacher Awareness, Adapting Research Techniques.
ERIC Educational Resources Information Center
Kepler, Karen B.
This study investigated the ability of middle school teachers to use descriptive feedback from their students in changing their teaching behavior. One homeroom group of twenty-five students was observed in interaction with nine teachers of math, English, social studies, and science over a one-year period to elicit both quantifiable and qualitative…
ERIC Educational Resources Information Center
Jansen, Amanda; Spitzer, Sandy M.
2009-01-01
In this study, we examined prospective middle school mathematics teachers' reflective thinking skills to understand how they learned from their own teaching practice when engaging in a modified lesson study experience. Our goal was to identify variations among prospective teachers' descriptions of students' thinking and frequency of their…
Modified-PCNL without modified instruments: a description of technique.
Lipsky, Michael J; Shapiro, Edan Y; Cha, Doh Yoon; Gupta, Mantu
2013-06-01
Mini-PCNL was developed to reduce the morbidity of PCNL by using smaller tract sizes. Most mini-techniques, however, require specialized instruments and use ureteroscopes as surrogates for nephroscopes, resulting in decreased visualization, poor irrigation, and difficult fragment extraction. We describe our modified technique (mPCNL) that allows for the use of standard PCNL equipment through a tract that is smaller than standard PCNL (sPCNL) but larger than previously reported for mini-PCNL. After ureteral access with a coaxial anti-retropulsion device, the patient is placed in the prone position. After percutaneous access under fluoroscopic guidance, a 24F balloon dilating catheter is used to place a 24F Amplatz sheath. A standard 26F rigid nephroscope is used to complete the entire procedure, with the modification of selectively removing the outer sheath to allow the scope to fit in the smaller tract. Standard lithotripters and graspers are used, as necessary. ROLE IN PRACTICE: We have performed this technique on 52 patients with a mean stone burden of 19.4 mm. Overall stone-free rate was 100%, even for stones >2 cm. This technique allows for improved visualization and irrigation compared with other mini-PCNL procedures and obviates the need to purchase specialized equipment.
The Critical Incident Technique: A Description of the Method.
ERIC Educational Resources Information Center
Stano, Michael
Critical Incident Technique (CIT) involves the collection of real-world examples of behavior that characterize either very effective or very ineffective performance of some activity. The principal advantage of the CIT is that it generates data based on actual behavior rather than on a particular researcher's subjectivity. The CIT has much to offer…
Experience Matters: Innovative Techniques Add up to Mathematical Achievement
ERIC Educational Resources Information Center
Savitz, Ryan M.; Savitz, Fred R.
2010-01-01
The first-year college experience is anxiety-producing, and for college students, especially those representing traditionally underserved populations, the experience can be particularly daunting. To mitigate against potential failure a father/son team, the father a professor of education and the son a professor of mathematics, pooled their…
Online Resources in Mathematics, Teachers' Geneses and Didactical Techniques
ERIC Educational Resources Information Center
Bueno-Ravel, Laetitia; Gueudet, Ghislaine
2009-01-01
The study we present here concerns the consequences of integrating online resources into the teaching of mathematics. We focus on the interaction between teachers and specific online resources they draw on: e-exercise bases. We propose a theoretical approach to study the associated phenomena, combining instrumental and anthropological…
Success in Mathematics Through Aural Reading Techniques (SMART).
ERIC Educational Resources Information Center
Sganga, Frank
The focus of this project was to individualize mathematics instruction for fifth- and sixth-grade students. Tapes and student study sheets were prepared for different ability levels. These materials allowed teachers to place students in a self-instruction package commensurate with the students' ability and allowed students to proceed at their own…
Goddard trajectory determination subsystem: Mathematical specifications
NASA Technical Reports Server (NTRS)
Wagner, W. E. (Editor); Velez, C. E. (Editor)
1972-01-01
The mathematical specifications of the Goddard trajectory determination subsystem of the flight dynamics system are presented. These specifications include the mathematical description of the coordinate systems, dynamic and measurement model, numerical integration techniques, and statistical estimation concepts.
Navigated placement of iliac bolts: description of a new technique.
Garrido, Ben J; Wood, Ken E
2011-04-01
Image navigation has improved the safety and ability to perform complex spinal procedures where visibility is not optimal or anatomic deformity is present. Numerous published studies are available demonstrating its effectiveness in improved pedicle screw placement in complex multiplanar deformities. Studies have also demonstrated image navigation technology versatility; however, stabilization of the lumbopelvic junction with navigated iliac bolt fixation has not been reported. To describe an innovative versatile application of image navigation technology in spine surgery. We examine the safety, accuracy, and effectiveness of navigated iliac bolt placement while minimizing challenges associated with current techniques. Case series. Five patients requiring lumbopelvic fixation for multiple indications, including lumbosacral pseudoarthrosis, complex sacral fracture patterns, compromised revision sacral fixation, and as an adjunct to degenerative deformity with multilevel fusion, underwent navigated iliac bolt placement. Accurate placement was verified using intraoperative computed tomography (CT) imaging using O-ARM (Medtronic, Inc.) after placement. Five patients requiring lumbopelvic fixation have undergone navigated iliac bolt placement using Medtronic Stealth Station Treon in conjunction with the O-ARM (Medtronic, Inc.). A right percutaneous posterior superior iliac spine (PSIS) reference frame was placed at the superior lateral margin of the PSIS, and bilateral iliac bolts were placed via navigation using both the anatomic and traditional surgical techniques. Both techniques were performed without direct notch palpation and minimal soft-tissue exposure. Postplacement intraoperative CT imaging was obtained to confirm position and trajectory of the bolts using O-ARM (Medtronic, Inc.). Ten iliac bolts were successfully placed in five patients. Intraoperative CT demonstrated ideal iliac screw bone placement projecting within 2 cm over sciatic notch, between pelvic
Explosion-proof fiber optic fire detector: design and mathematical description
NASA Astrophysics Data System (ADS)
Kazakov, V. I.; Moskaletz, O. D.
2014-10-01
The problem of early fire detection in areas classified as potentially explosive is considered in this paper. These include, for example, some types of facilities and plants, which may cause environmental disasters in case of fires. Hard safety requirements impose serious terms for the technical performance the detectors for the protection of such objects from the fire. Detector itself should not cause a fire. The main danger is open conductive parts in the construction of the sensitive elements of detectors, which can lead to the generation of sparks and fire. The using of fiber-optic technology allows creating smoke and heating fire detectors, which only the sensors will be located in the protected area, and all electronic components generate signals and their processing may be removed at considerable distances measured by kilometers. The block diagram of the fire smoke point detector based on fiber-optic technology is considered, the mathematical description of the propagation of optical radiation through the sensing element of the detector is provided, sensitivity is analyzed.
Incorporation of Monte-Carlo Computer Techniques into Science and Mathematics Education.
ERIC Educational Resources Information Center
Danesh, Iraj
1987-01-01
Described is a Monte-Carlo method for modeling physical systems with a computer. Also discussed are ways to incorporate Monte-Carlo simulation techniques for introductory science and mathematics teaching and also for enriching computer and simulation courses. (RH)
Sonographically guided sternoclavicular joint injection: description of technique and validation.
Pourcho, Adam M; Sellon, Jacob L; Smith, Jay
2015-02-01
The primary purpose of this investigation was to describe and validate a sonographically guided technique for injecting the sternoclavicular joint (SCJ) using a cadaveric model. A single experienced operator (J.S.) completed 13 sonographically guided SCJ injections on 7 unembalmed cadaveric specimens (4 male and 3 female) using an out-of-plane, caudad-to-cephalad technique to place 1 mL of diluted blue latex into the joint. Within 72 hours, study coinvestigators dissected each specimen to determine the injectate location. All 13 injections accurately placed latex into the SCJ with a predilection for the clavicular side (accuracy, 100%; 95% confidence interval, 73%-100%). Three injections (23%) placed all latex on the clavicular side of the SCJ in the presence of a complete intra-articular disk. Dissection revealed incomplete degenerated disks in the remaining 10 joints. Seven of these injections (54%) clearly placed more than 80% of the latex on the clavicular side, whereas the remaining 3 injections (23%) showed nearly equal latex distribution between the clavicular and sternal sides. No injection resulted in neurovascular injury or extracapsular flow. Sonographically guided SCJ injections can be considered in the diagnosis and management of patients presenting with medial shoulder pain syndromes and, using the technique described herein, have a predilection to target the clavicular portion of the joint. In younger patients with possible complete intra-articular disks or in patients with sternal-side conditions, practitioners should consider confirming sternal-side flow after injection or attempt to specifically target the sternal side of the joint. © 2015 by the American Institute of Ultrasound in Medicine.
A Spectrum of Pedagogical Awareness for Undergraduate Mathematics: From "Tricks" to "Techniques"
ERIC Educational Resources Information Center
Nardi, Elena; Jaworski, Barbara; Hegedus, Stephen
2005-01-01
We describe a four-level spectrum of pedagogical awareness (SPA) that emerged from the analysis of six undergraduate mathematics tutors' (1) conceptualizations of their first-year students' difficulties; (2) descriptive accounts of their strategies for facilitating the overcoming of these difficulties; and (3) self-reflective accounts regarding…
A Spectrum of Pedagogical Awareness for Undergraduate Mathematics: From "Tricks" to "Techniques"
ERIC Educational Resources Information Center
Nardi, Elena; Jaworski, Barbara; Hegedus, Stephen
2005-01-01
We describe a four-level spectrum of pedagogical awareness (SPA) that emerged from the analysis of six undergraduate mathematics tutors' (1) conceptualizations of their first-year students' difficulties; (2) descriptive accounts of their strategies for facilitating the overcoming of these difficulties; and (3) self-reflective accounts regarding…
Cystoscopic-assisted partial cystectomy: description of technique and results
Gofrit, Ofer N; Shapiro, Amos; Katz, Ran; Duvdevani, Mordechai; Yutkin, Vladimir; Landau, Ezekiel H; Zorn, Kevin C; Hidas, Guy; Pode, Dov
2014-01-01
Background Partial cystectomy provides oncological results comparable with those of radical cystectomy in selected patients with invasive bladder cancer without the morbidity associated with radical cystectomy and urinary diversion. We describe a novel technique of partial cystectomy that allows accurate identification of tumor margins while minimizing damage to the rest of the bladder. Methods During the study period, 30 patients underwent partial cystectomy for invasive high-grade cancer. In 19 patients, the traditional method of tumor identification was used, ie, identifying the tumor by palpation and cystotomy. In eleven patients, after mobilization of the bladder, flexible cystoscopy was done and the light of the cystoscope was pointed toward one edge of the planned resected ellipse around the tumor, thus avoiding cystotomy. Results Patients who underwent partial cystectomy using the novel method were similar in all characteristics to patients operated on using the traditional technique except for tumor diameter which was significantly larger in patients operated on using the novel method (4.3±1.5 cm versus 3.11±1.18 cm, P=0.032). Complications were rare in both types of surgery. The 5-year local recurrence-free survival was marginally superior using the novel method (0.8 versus 0.426, P=0.088). Overall, disease-specific and disease-free survival rates were similar. Conclusion The use of a flexible cystoscope during partial cystectomy is a simple, low-cost maneuver that assists in planning the bladder incision and minimizes injury to the remaining bladder by avoiding the midline cystotomy. Initial oncological results show a trend toward a lower rate of local recurrence compared with the standard method. PMID:25368846
NASA Astrophysics Data System (ADS)
Bender, Carl
2017-01-01
The theory of complex variables is extremely useful because it helps to explain the mathematical behavior of functions of a real variable. Complex variable theory also provides insight into the nature of physical theories. For example, it provides a simple and beautiful picture of quantization and it explains the underlying reason for the divergence of perturbation theory. By using complex-variable methods one can generalize conventional Hermitian quantum theories into the complex domain. The result is a new class of parity-time-symmetric (PT-symmetric) theories whose remarkable physical properties have been studied and verified in many recent laboratory experiments.
Mathematical description of complex chemical kinetics and application to CFD modeling codes
NASA Technical Reports Server (NTRS)
Bittker, D. A.
1993-01-01
A major effort in combustion research at the present time is devoted to the theoretical modeling of practical combustion systems. These include turbojet and ramjet air-breathing engines as well as ground-based gas-turbine power generating systems. The ability to use computational modeling extensively in designing these products not only saves time and money, but also helps designers meet the quite rigorous environmental standards that have been imposed on all combustion devices. The goal is to combine the very complex solution of the Navier-Stokes flow equations with realistic turbulence and heat-release models into a single computer code. Such a computational fluid-dynamic (CFD) code simulates the coupling of fluid mechanics with the chemistry of combustion to describe the practical devices. This paper will focus on the task of developing a simplified chemical model which can predict realistic heat-release rates as well as species composition profiles, and is also computationally rapid. We first discuss the mathematical techniques used to describe a complex, multistep fuel oxidation chemical reaction and develop a detailed mechanism for the process. We then show how this mechanism may be reduced and simplified to give an approximate model which adequately predicts heat release rates and a limited number of species composition profiles, but is computationally much faster than the original one. Only such a model can be incorporated into a CFD code without adding significantly to long computation times. Finally, we present some of the recent advances in the development of these simplified chemical mechanisms.
Mathematical Description of Complex Chemical Kinetics and Application to CFD Modeling Codes
NASA Technical Reports Server (NTRS)
Bittker, D. A.
1993-01-01
A major effort in combustion research at the present time is devoted to the theoretical modeling of practical combustion systems. These include turbojet and ramjet air-breathing engines as well as ground-based gas-turbine power generating systems. The ability to use computational modeling extensively in designing these products not only saves time and money, but also helps designers meet the quite rigorous environmental standards that have been imposed on all combustion devices. The goal is to combine the very complex solution of the Navier-Stokes flow equations with realistic turbulence and heat-release models into a single computer code. Such a computational fluid-dynamic (CFD) code simulates the coupling of fluid mechanics with the chemistry of combustion to describe the practical devices. This paper will focus on the task of developing a simplified chemical model which can predict realistic heat-release rates as well as species composition profiles, and is also computationally rapid. We first discuss the mathematical techniques used to describe a complex, multistep fuel oxidation chemical reaction and develop a detailed mechanism for the process. We then show how this mechanism may be reduced and simplified to give an approximate model which adequately predicts heat release rates and a limited number of species composition profiles, but is computationally much faster than the original one. Only such a model can be incorporated into a CFD code without adding significantly to long computation times. Finally, we present some of the recent advances in the development of these simplified chemical mechanisms.
Mathematical description of complex chemical kinetics and application to CFD modeling codes
NASA Technical Reports Server (NTRS)
Bittker, D. A.
1993-01-01
A major effort in combustion research at the present time is devoted to the theoretical modeling of practical combustion systems. These include turbojet and ramjet air-breathing engines as well as ground-based gas-turbine power generating systems. The ability to use computational modeling extensively in designing these products not only saves time and money, but also helps designers meet the quite rigorous environmental standards that have been imposed on all combustion devices. The goal is to combine the very complex solution of the Navier-Stokes flow equations with realistic turbulence and heat-release models into a single computer code. Such a computational fluid-dynamic (CFD) code simulates the coupling of fluid mechanics with the chemistry of combustion to describe the practical devices. This paper will focus on the task of developing a simplified chemical model which can predict realistic heat-release rates as well as species composition profiles, and is also computationally rapid. We first discuss the mathematical techniques used to describe a complex, multistep fuel oxidation chemical reaction and develop a detailed mechanism for the process. We then show how this mechanism may be reduced and simplified to give an approximate model which adequately predicts heat release rates and a limited number of species composition profiles, but is computationally much faster than the original one. Only such a model can be incorporated into a CFD code without adding significantly to long computation times. Finally, we present some of the recent advances in the development of these simplified chemical mechanisms.
TPS as an Effective Technique to Enhance the Students' Achievement on Writing Descriptive Text
ERIC Educational Resources Information Center
Sumarsih, M. Pd.; Sanjaya, Dedi
2013-01-01
Students' achievement in writing descriptive text is very low, in this study Think Pair Share (TPS) is applied to solve the problem. Action research is conducted for the result. Additionally, qualitative and quantitative techniques are applied in this research. The subject of this research is grade VIII in Junior High School in Indonesia. From…
ERIC Educational Resources Information Center
Zainuddin
2015-01-01
This study was aimed at finding out the effectiveness of applying Cooperative Integrated Reading and Composition (CIRC) Technique on Students' Reading Descriptive Text Achievement. In other words, the objective of this study was to find out if there was a significant effect of applying Cooperative Integrated Reading and Composition (CIRC)…
NASA Astrophysics Data System (ADS)
Gurova, E. G.
2016-08-01
During the researches the mathematical description of the traction characteristics of the stiffness compensators of the vibration isolation devices, relatively of the each axis, has been done. Representation of the compensators properties considers the variable load, thereby provide the wide enough spectrum of the action of the suggested vibration isolators. The derived expressions are valid for all three axes of space at the different stiffnesses, i.e. basic basic and two compensating. The research was supported by the scholarships of Russian Federation President for young scientists №184 from 10th of March 2015.
Mathematical representations of turbulent mixing
NASA Technical Reports Server (NTRS)
Farmer, R. C.; Audeh, B.
1973-01-01
A basic description is given of the mathematical tools and models which are presently used to represent turbulent, free shear layers. Recommendations are included for ways in which current modeling techniques can be improved.
ERIC Educational Resources Information Center
Salam, Abdus; Hossain, Anwar; Rahman, Shahidur
2015-01-01
This study investigates the effects of game playing on performance and attitudes of students towards mathematics of Grade VIII. The study was undergone by implementing TGT technique for the experimental group and typical lecture-based approach for the control group. A same achievement test was employed as in both pre-test and post-test, an…
ERIC Educational Resources Information Center
Duxbury, Mark
2004-01-01
An enzymatic laboratory experiment based on the analysis of serum is described that is suitable for students of clinical chemistry. The experiment incorporates an introduction to mathematical method-comparison techniques in which three different clinical glucose analysis methods are compared using linear regression and Bland-Altman difference…
ERIC Educational Resources Information Center
Ong, Ewe Gnoh; Lim, Chap Sam; Ghazali, Munirah
2010-01-01
The purpose of this study was to examine the changes in novice and experienced mathematics teachers' questioning techniques. This study was conducted in Sarawak where ten (experienced and novice) teachers from two schools underwent the lesson study process for fifteen months. Four data collection methods namely, observation, interview, lesson…
Dimensional Analysis: an Elegant Technique for Facilitating the Teaching of Mathematical Modelling.
ERIC Educational Resources Information Center
Fay, Temple H.; Joubert, Stephan V.
2002-01-01
Dimension analysis is promoted as a technique that promotes better understanding of the role of units and dimensions in mathematical modeling problems. Dimensional analysis is shown to lead to interesting systems of linear equations to solve, and can point the way to more quantitative analysis. Two student problems are discussed. (Author/MM)
ERIC Educational Resources Information Center
Ong, Ewe Gnoh; Lim, Chap Sam; Ghazali, Munirah
2010-01-01
The purpose of this study was to examine the changes in novice and experienced mathematics teachers' questioning techniques. This study was conducted in Sarawak where ten (experienced and novice) teachers from two schools underwent the lesson study process for fifteen months. Four data collection methods namely, observation, interview, lesson…
ERIC Educational Resources Information Center
Duxbury, Mark
2004-01-01
An enzymatic laboratory experiment based on the analysis of serum is described that is suitable for students of clinical chemistry. The experiment incorporates an introduction to mathematical method-comparison techniques in which three different clinical glucose analysis methods are compared using linear regression and Bland-Altman difference…
A Description and Characterization of Student Activity in an Open, Online, Mathematics Help Forum
ERIC Educational Resources Information Center
van de Sande, Carla
2011-01-01
Free, open, online, calculus forums are websites where students from around the world can post course-related queries that may be viewed and responded to by anonymous others. These sites are an emergent resource for students seeking help and have become a part of many students' mathematical experience. The purpose of this paper is to introduce and…
A Description and Characterization of Student Activity in an Open, Online, Mathematics Help Forum
ERIC Educational Resources Information Center
van de Sande, Carla
2011-01-01
Free, open, online, calculus forums are websites where students from around the world can post course-related queries that may be viewed and responded to by anonymous others. These sites are an emergent resource for students seeking help and have become a part of many students' mathematical experience. The purpose of this paper is to introduce and…
A general model for Io's neutral gas clouds. I - Mathematical description
NASA Technical Reports Server (NTRS)
Smyth, W. H.; Combi, M. R.
1988-01-01
A general mathematical formalism for calculating the physical properties of any of Io's neutral gas clouds (Na, K, O, S, SO2) is presented. The dynamical effects of both the gravitational fields of Io and Jupiter and solar radiation pressure are included, in addition to the many complex space- and time-dependent interactions that occur between the neutral clouds and the plasma torus. The importance of this new model in studying both the plasma conditions prevalent in the inner planetary magnetosphere and the nature of Io's local atmosphere is discussed. A numerical method for evaluating the physical properties of the neutral clouds using the new model is described.
NASA Technical Reports Server (NTRS)
Przekwas, A. J.; Singhal, A. K.; Tam, L. T.
1984-01-01
The capability of simulating three dimensional two phase reactive flows with combustion in the liquid fuelled rocket engines is demonstrated. This was accomplished by modifying an existing three dimensional computer program (REFLAN3D) with Eulerian Lagrangian approach to simulate two phase spray flow, evaporation and combustion. The modified code is referred as REFLAN3D-SPRAY. The mathematical formulation of the fluid flow, heat transfer, combustion and two phase flow interaction of the numerical solution procedure, boundary conditions and their treatment are described.
Hara, Toshihide; Iriyama, Satoshi; Makino, Kimiko; Terada, Hiroshi; Ohya, Masanori
2010-01-01
It is known that Drug Delivery System (DDS) is useful to remedy against tumors for the reduction of side effects and the effective dosage. However the shape, in particular, the size of drug (medicine) is empirically decided in the present stage, which will be related to a question how much medicine should be dosed. Taking a particular reaction of tumor tissues called the EPR effect into consideration, we try to mathematically describe the behavior (dynamics) of drug in blood vessel by applying several techniques used in mathematics and physics. In this paper, we estimate the configuration of drug which is most effective to remedy for tumors under various conditions. As a result, this model and its simulation will be useful to design the drug in nano-level.
Entrainment Descriptions for Mathematical Modeling of Pumped-Storage Inflows in Reservoirs.
1985-10-01
demonstrated that the entrainment description can be ., one of the most important inputs to a PS reservoir simulation model. ..... Therefore, adequate...discharged into arbitrary stratifica- ............. tion. The results were then reduced to a form suitable for inclusion into reservoir simulation models...integral buoyant jet model, as adapted to the reservoir simulation code, is referred to as subroutine SBJET (Strongly Buoyant JET). 26. Fan and
An Approach for a Mathematical Description of Human Root Canals by Means of Elementary Parameters.
Dannemann, Martin; Kucher, Michael; Kirsch, Jasmin; Binkowski, Alexander; Modler, Niels; Hannig, Christian; Weber, Marie-Theres
2017-04-01
Root canal geometry is an important factor for instrumentation and preparation of the canals. Curvature, length, shape, and ramifications need to be evaluated in advance to enhance the success of the treatment. Therefore, the present study aimed to design and realize a method for analyzing the geometric characteristics of human root canals. Two extracted human lower molars were radiographed in the occlusal direction using micro-computed tomographic imaging. The 3-dimensional geometry of the root canals, calculated by a self-implemented image evaluation algorithm, was described by 3 different mathematical models: the elliptical model, the 1-circle model, and the 3-circle model. The different applied mathematical models obtained similar geometric properties depending on the parametric model used. Considering more complex root canals, the differences of the results increase because of the different adaptability and the better approximation of the geometry. With the presented approach, it is possible to estimate and compare the geometry of natural root canals. Therefore, the deviation of the canal can be assessed, which is important for the choice of taper of root canal instruments. Root canals with a nearly elliptical cross section are reasonably approximated by the elliptical model, whereas the 3-circle model obtains a good agreement for curved shapes. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Esteva, Lourdes; Mo Yang, Hyun
2005-12-01
We propose a mathematical model to assess the effects of irradiated (or transgenic) male insects introduction in a previously infested region. The release of sterile male insects aims to displace gradually the natural (wild) insect from the habitat. We discuss the suitability of this release technique when applied to peri-domestically adapted Aedes aegypti mosquitoes which are transmissors of Yellow Fever and Dengue disease.
NASA Astrophysics Data System (ADS)
Lavrikov, SV; Mikenina, OA; Revuzhenko, AF
2017-02-01
Under analysis is an approach to mathematical modeling of structurally inhomogeneous rocks considering structural hierarchy and internal self-balanced stresses. The fields of stresses and strains at various scale levels of rock mass medium are characterized using the non-Archimedean analysis methods. It is shown that such model describes accumulationtion of elastic energy in the form of internal self-balanced stresses on a micro-scale. The finite element algorithm and a computer program are developed to solve plane boundary-value problems. The calculated data on compression of a rock specimen are reported. The paper shows that the behavior of plastic strain zones largley depends on the pre-set initital micro-stresses.
ERIC Educational Resources Information Center
Mac Lane, Saunders
1980-01-01
This is a review of the current research in mathematics involving breadth of ideas. Research includes topics in number theory, classification of all finite simple groups, the representation of group aids in their application to the study of symmetry. (Author/SA)
ERIC Educational Resources Information Center
Costellano, Janet; Scaffa, Matthew
The product of a Special Studies Institute, this teacher developed resource guide for the emotionally handicapped (K-6) presents 37 activities designed to develop mathematics concepts and skills utilizing the urban out-of-doors. Focus is on experiencing math models, patterns, problems, and relationships found in an urban environment. Activities…
SHETTY, ANIL N.; CHIANG, SHARON; MALETIC-SAVATIC, MIRJANA; KASPRIAN, GREGOR; VANNUCCI, MARINA; LEE, WESLEY
2016-01-01
In this article, we discuss the theoretical background for diffusion weighted imaging and diffusion tensor imaging. Molecular diffusion is a random process involving thermal Brownian motion. In biological tissues, the underlying microstructures restrict the diffusion of water molecules, making diffusion directionally dependent. Water diffusion in tissue is mathematically characterized by the diffusion tensor, the elements of which contain information about the magnitude and direction of diffusion and is a function of the coordinate system. Thus, it is possible to generate contrast in tissue based primarily on diffusion effects. Expressing diffusion in terms of the measured diffusion coefficient (eigenvalue) in any one direction can lead to errors. Nowhere is this more evident than in white matter, due to the preferential orientation of myelin fibers. The directional dependency is removed by diagonalization of the diffusion tensor, which then yields a set of three eigenvalues and eigenvectors, representing the magnitude and direction of the three orthogonal axes of the diffusion ellipsoid, respectively. For example, the eigenvalue corresponding to the eigenvector along the long axis of the fiber corresponds qualitatively to diffusion with least restriction. Determination of the principal values of the diffusion tensor and various anisotropic indices provides structural information. We review the use of diffusion measurements using the modified Stejskal–Tanner diffusion equation. The anisotropy is analyzed by decomposing the diffusion tensor based on symmetrical properties describing the geometry of diffusion tensor. We further describe diffusion tensor properties in visualizing fiber tract organization of the human brain. PMID:27441031
A mathematical model for the description of the Coomassie brilliant blue protein assay.
Atherton, B A; Cunningham, E L; Splittgerber, A G
1996-01-15
The Coomassie brilliant blue dye-binding method for protein assay has become important relatively recently. The basis of the assay method is the binding of dye to protein, with production of a dye-protein complex which absorbs light intensely at 620 nm, but the mechanism of the binding process is not well understood. In this paper, two mathematical models for the binding process are developed, one involving the binding of both protonated (green) and deprotonated (blue) forms of the dye. The second model allows only binding of the blue species to proteins. These models are tested for their ability to estimate number of dye-binding sites (n) and binding constants (Kd) from protein assay data. The models are also tested for their ability to reproduce the experimental assay curve using either known values or reasonable estimates of the equation parameters. The models are shown to be approximately equal in ability to reproduce experimental data related to the protein assay, which somewhat favors the simpler of the two models. In this paper, a method for estimating n and Kd from standard curve-fitting procedures is established. Hitherto, binding constants were only available from assay data taken under conditions of very large molar protein/dye ratios. The possibility of protonated forms of the dye binding to proteins was not ruled out by this study, but for many purposes the use of the simple dye-binding model, in which only the deprotonated dye species binds, is sufficient.
Shetty, Anil N; Chiang, Sharon; Maletic-Savatic, Mirjana; Kasprian, Gregor; Vannucci, Marina; Lee, Wesley
2014-01-01
In this article, we discuss the theoretical background for diffusion weighted imaging and diffusion tensor imaging. Molecular diffusion is a random process involving thermal Brownian motion. In biological tissues, the underlying microstructures restrict the diffusion of water molecules, making diffusion directionally dependent. Water diffusion in tissue is mathematically characterized by the diffusion tensor, the elements of which contain information about the magnitude and direction of diffusion and is a function of the coordinate system. Thus, it is possible to generate contrast in tissue based primarily on diffusion effects. Expressing diffusion in terms of the measured diffusion coefficient (eigenvalue) in any one direction can lead to errors. Nowhere is this more evident than in white matter, due to the preferential orientation of myelin fibers. The directional dependency is removed by diagonalization of the diffusion tensor, which then yields a set of three eigenvalues and eigenvectors, representing the magnitude and direction of the three orthogonal axes of the diffusion ellipsoid, respectively. For example, the eigenvalue corresponding to the eigenvector along the long axis of the fiber corresponds qualitatively to diffusion with least restriction. Determination of the principal values of the diffusion tensor and various anisotropic indices provides structural information. We review the use of diffusion measurements using the modified Stejskal-Tanner diffusion equation. The anisotropy is analyzed by decomposing the diffusion tensor based on symmetrical properties describing the geometry of diffusion tensor. We further describe diffusion tensor properties in visualizing fiber tract organization of the human brain.
NASA Technical Reports Server (NTRS)
Bekey, G. A.
1971-01-01
Studies are summarized on the application of advanced analytical and computational methods to the development of mathematical models of human controllers in multiaxis manual control systems. Specific accomplishments include the following: (1) The development of analytical and computer methods for the measurement of random parameters in linear models of human operators. (2) Discrete models of human operator behavior in a multiple display situation were developed. (3) Sensitivity techniques were developed which make possible the identification of unknown sampling intervals in linear systems. (4) The adaptive behavior of human operators following particular classes of vehicle failures was studied and a model structure proposed.
Recommended procedures and techniques for the petrographic description of bituminous coals
Chao, E.C.T.; Minkin, J.A.; Thompson, C.L.
1982-01-01
bed. The use of bulk-specific-gravity determinations is alo recommended for identification and characterization of the distinctive lithologic units. The availability of an AIAS also enhances the capability to acquire textural information. Ranges of size of maceral and mineral grains can be quickly and precisely determined by use of an AIAS. We assume that shape characteristics of coal particles can also be readily evaluated by automated image analysis, although this evaluation has not yet been attempted in our laboratory. Definitive data on the particulate mineral content of coal constitute another important segment of petrographic description. Characterization of mineral content may be accomplished by optical identification, electron microprobe analysis, X-ray diffraction, and scanning and transmission electron microscopy. Individual mineral grains in place in polished blocks or polished this sections, or separated from the coal matrix by sink-float methods are studied by analytical techniques appropriate to the conditions of sampling. Finally, whenever possible, identification of the probable genus or plant species from which a given coal component is derived will add valuable information and meaning to the petrographic description. ?? 1982.
Mathematical Model and Artificial Intelligent Techniques Applied to a Milk Industry through DSM
NASA Astrophysics Data System (ADS)
Babu, P. Ravi; Divya, V. P. Sree
2011-08-01
The resources for electrical energy are depleting and hence the gap between the supply and the demand is continuously increasing. Under such circumstances, the option left is optimal utilization of available energy resources. The main objective of this chapter is to discuss about the Peak load management and overcome the problems associated with it in processing industries such as Milk industry with the help of DSM techniques. The chapter presents a generalized mathematical model for minimizing the total operating cost of the industry subject to the constraints. The work presented in this chapter also deals with the results of application of Neural Network, Fuzzy Logic and Demand Side Management (DSM) techniques applied to a medium scale milk industrial consumer in India to achieve the improvement in load factor, reduction in Maximum Demand (MD) and also the consumer gets saving in the energy bill.
SEVERE VALGUS DEFORMITY OF THE KNEE: DESCRIPTION OF NEW SURGICAL TECHNIQUE FOR ITS CORRECTION
da Silva, Robson Rocha; Matos, Marcos Almeida; Pimentel, Maurício; Martins, Bruno Jacomeli; Oliveira, Rafael Valadares
2015-01-01
Varus supracondylar osteotomy of the femur is the established procedure for treating painful knees that present lateral arthrosis and valgus deformity. In descriptions of the conventional surgical techniques, there are divergences regarding the location, access route, correction level, fixation type and area for synthesis insertion. This is most evident in cases of severe valgus with angles greater than 30° and distal femoral deformation, in association with hypoplasia of the lateral condyle. The authors describe a new surgical technique for distal femoral osteotomy, based on anatomical and geometrical criteria, which was developed in their clinic for treating severe valgus cases, and they present one of the cases treated. In the new technique, the wedge to be surgically resected has an oblique direction and the format of an isosceles triangle. This new proposal thus seeks to resolve problems that have been presented in such cases, through enabling valgus correction without causing any new deformity of the distal femur. Good cortical bone contact is promoted, and application of a stable synthesis system is made easier. However, the age limits for such patients and the degree of knee arthrosis that might contraindicate this procedure remain unknown. Hence, a larger sample and longer follow-up for operated cases are required. PMID:27042630
Lanska, D J; Remler, B
1997-05-01
The original description of benign paroxysmal positioning vertigo (BPPV) has been variously attributed to Bárány, Adler, and others. In addition, the proper eponymic designation for the provocative positioning test used to diagnose BPPV has been unclear, because authors use a variety of different terms, including Bárány, Nylén-Bárány, Nylén, Hallpike, Hallpike-Dix, and Dix-Hallpike to refer to the procedure in current use. Based on a review of the extant medical literature, Bárány was the first to describe the condition in detail, and Dix and Hallpike were the first to clearly describe both the currently used provocative positioning technique and the essential clinical manifestations of benign paroxysmal positioning vertigo elicited by that technique. Nevertheless, despite their important contributions, neither Bárány nor Dix and Hallpike understood the pathophysiology of BPPV nor did they appreciate that the positioning techniques they used actually demonstrated pathology in the semicircular canals rather than the utricle. The modern understanding of the pathophysiology of BPPV began with Schuknecht's proposal that the dysfunction resulted from the gravity-dependent movement of loose or fixed dense material within the posterior semicircular canal ("cupulolithiasis"). Although Schuknecht's formulations were not consistent with all clinical features of the disease, they led to the modern "canalolithiasis theory" and highly effective canalith repositioning or "liberatory" maneuvers for BPPV.
NASA Astrophysics Data System (ADS)
Petoshin, V. I.; Chasovnikov, E. A.
2011-05-01
Aerodynamic loads in problems of flight dynamics of passenger aircraft in stalled flow regimes are described using a mathematical model that includes an ordinary linear first-order differential equation. A procedure for determining the parameters of the mathematical model is proposed which is based on approximating experimental frequency characteristics with the frequency characteristics of the linearized mathematical model. The mathematical model was verified by tests of a modern passenger aircraft model in a wind tunnel.
ERIC Educational Resources Information Center
McLoughlin, M. Padraig M. M.
2008-01-01
The author of this paper submits the thesis that learning requires doing; only through inquiry is learning achieved, and hence this paper proposes a programme of use of a modified Moore method in a Probability and Mathematical Statistics (PAMS) course sequence to teach students PAMS. Furthermore, the author of this paper opines that set theory…
Bohl, Michael A; Mooney, Michael A; Catapano, Joshua S; Almefty, Kaith K; Preul, Mark C; Chang, Steve W; Kakarla, U Kumar; Reece, Edward M; Turner, Jay D; Porter, Randall W
2017-03-14
Cadaveric feasibility study. To assess the anatomic and technical feasibility of rotating a clavicular segment on a sternocleidomastoid muscle (SCM) pedicle into the ventral cervical spine using a cadaveric model and to provide the first clinical case description of performing this procedure. Reconstruction of the anterior cervical spine in patients with a high risk of pseudoarthrosis may require the use of a vascularized bone graft (VBG). A vascularized clavicular graft rotated on an SCM pedicle would afford all the benefits of a VBG without the added morbidity of free-tissue transfer; however, this technique has not been described. A multidisciplinary team hypothesized that it would be anatomically and technically feasible to rotate a pedicled clavicular bone graft from the bottom of C2 to the top of T2 via an anterior approach. Five cadavers underwent bilateral anterior neck dissections for a total of 10 clavicular graft assessments. A case report describes the use of a clavicular VBG in a patient with a 3-level corpectomy defect and a history of failed fusion. Ten clavicles were rotated on an SCM pedicle. The grafts were either harvested as an entire segment or as the superior two-thirds of clavicle, leaving the inferior one-third in situ with pectoralis attachments intact. All grafts reached from the bottom of C2 to the top of T2. When the entire length of exposed clavicle was mobilized, it could cover 5-6 levels. The case report highlights technical challenges of this procedure in a living patient and provides clinical context for its potential utility in reconstruction of the ventral cervical spine. This surgical technique is best suited for patients with long-segment cervical defects and an increased risk of pseudarthrosis. Further clinical experience with this technique is required before definitive conclusions can be made. 5.
Pope, G.A.; Sepehrnoori, K.; Delshad, M.; Ferreira, L.; Gupta, A.; Maroongroge, V.
1994-11-01
This is the final report of a three year research project on the use of tracers for reservoir characterization. The objective of this research was to develop advanced, innovative techniques for the description of reservoir characteristics using both single-well backflow and interwell tracer tests. (1) The authors implemented and validated tracer modeling features in a compositional simulator (UTCOMP). (2) They developed and applied a new single well tracer test for estimating reservoir heterogeneity. (3) They developed and applied a new single well tracer test for estimating reservoir wettability in-situ. (4) They developed a new, simple and efficient method to analyze two well tracer tests based upon type curve matching and illustrated its use with actual field tracer data. (5) They developed a new method for deriving an integrated reservoir description based upon combinatorial optimization schemes. (6) They developed a new, interwell tracer test for reservoir heterogeneity called vertical tracer profiling (VTP) and demonstrated its advantages over conventional interwell tracer testing. (7) They developed a simple and easy analytical method to estimate swept pore volume from interwell tracer data and showed both the theoretical basis for this method and its practical utility. (8) They made numerous enhancements to our compositional reservoir simulator such as including the full permeability tensor, adding faster solvers, improving its speed and robustness and making it easier to use (better I/0) for tracer simulation problems. (9) They applied the enhanced version of UTCOMP to the analysis of interwell tracer data using perfluorocarbons at Elks Hill Naval Petroleum Reserve. All of these accomplishments taken together have significantly improved the state of reservoir tracer technology and have demonstrated that it is a far more powerful and useful tool for quantitative reservoir characterization than previously realized or practiced by the industry.
New mathematical technique for determining the parameters of gas permeation through solids
Kohls, J.F.
1980-01-01
The solution of Fick's equation for gas permeation through solid flat membranes yields a throughput rate equation with two unknown parameters, diffusivity and solubility. The common methods used to evaluate these parameters rely on knowing the equilibrium throughput rate. This equilibrium rate is in some cases rapidly established (on the order of seconds), in other cases slowly established (order of months). Thus, permeation measurements may require equipment usage over a long time period, precluding its use for other experiments. A mathematical technique for predicting the permeation parameters using the unequilibrated portion of the permeation throughput curve has been developed which overcomes this difficulty. The method developed (termed stabilized search) was tested with data simulated using a known amount of error. The predicted parameters were as accurate as the data, but the values were generated in only 20 to 40% of the time required for other methods.
Chronology of DIC technique based on the fundamental mathematical modeling and dehydration impact.
Alias, Norma; Saipol, Hafizah Farhah Saipan; Ghani, Asnida Che Abd
2014-12-01
A chronology of mathematical models for heat and mass transfer equation is proposed for the prediction of moisture and temperature behavior during drying using DIC (Détente Instantanée Contrôlée) or instant controlled pressure drop technique. DIC technique has the potential as most commonly used dehydration method for high impact food value including the nutrition maintenance and the best possible quality for food storage. The model is governed by the regression model, followed by 2D Fick's and Fourier's parabolic equation and 2D elliptic-parabolic equation in a rectangular slice. The models neglect the effect of shrinkage and radiation effects. The simulations of heat and mass transfer equations with parabolic and elliptic-parabolic types through some numerical methods based on finite difference method (FDM) have been illustrated. Intel®Core™2Duo processors with Linux operating system and C programming language have been considered as a computational platform for the simulation. Qualitative and quantitative differences between DIC technique and the conventional drying methods have been shown as a comparative.
ERIC Educational Resources Information Center
Pagliaro, Claudia M.; Kritzer, Karen L.
2013-01-01
Over decades and across grade levels, deaf/hard-of-hearing (d/hh) student performance in mathematics has shown a gap in achievement. It is unclear, however, exactly when this gap begins to emerge and in what areas. This study describes preschool d/hh children's knowledge of early mathematics concepts. Both standardized and nonstandardized measures…
ERIC Educational Resources Information Center
Pagliaro, Claudia M.; Kritzer, Karen L.
2013-01-01
Over decades and across grade levels, deaf/hard-of-hearing (d/hh) student performance in mathematics has shown a gap in achievement. It is unclear, however, exactly when this gap begins to emerge and in what areas. This study describes preschool d/hh children's knowledge of early mathematics concepts. Both standardized and nonstandardized measures…
MacLean, Adam L; Harrington, Heather A; Stumpf, Michael P H; Byrne, Helen M
2016-01-01
The last decade has seen an explosion in models that describe phenomena in systems medicine. Such models are especially useful for studying signaling pathways, such as the Wnt pathway. In this chapter we use the Wnt pathway to showcase current mathematical and statistical techniques that enable modelers to gain insight into (models of) gene regulation and generate testable predictions. We introduce a range of modeling frameworks, but focus on ordinary differential equation (ODE) models since they remain the most widely used approach in systems biology and medicine and continue to offer great potential. We present methods for the analysis of a single model, comprising applications of standard dynamical systems approaches such as nondimensionalization, steady state, asymptotic and sensitivity analysis, and more recent statistical and algebraic approaches to compare models with data. We present parameter estimation and model comparison techniques, focusing on Bayesian analysis and coplanarity via algebraic geometry. Our intention is that this (non-exhaustive) review may serve as a useful starting point for the analysis of models in systems medicine.
NASA Astrophysics Data System (ADS)
de Vicente, S.; Galiano, G.; Velasco, J.; Aróstegui, J. M.
Two-phase systems where a dense phase of small particles is fluidized with a gas flow appear in many industrial applications, among which the fluidized bed combustors are probably the most important. A homogenization technique allows us to formulate the mathematical model in form of the compressible Navier-Stokes system type with some particularities: 1) the volumetric fraction of the dense phase (analogous to the density in the Navier-Stokes equations) may vanish, 2) the constitutive viscosity law may depend in a nonlinear form on this density, 3) the source term is nonlinear and coupled with state equations involving drag forces and hydrodynamic pressure, and 4) the state equation for the collision pressure of dense phase blows up for finite values of the density. We develop a rigorous theory for a special kind of solutions we call stationary clouds. Such solutions exist only under restrictions on the geometry of combustor and on the boundary conditions that usually meet in engineering applications. In return, these solutions have a stationary one-dimensional structure very simple and, from them, it is possible to reconstruct much of the dynamics of the whole system, responding to most of the practical issues of interest. Finally, we study the linear stability for the trivial solutions corresponding to uniform fluidized states injecting plane wave perturbations in our equations. Depending on the parameters of the equations of state describing the collisions between solid particles, hydrodynamic pressure, and the values of blowing boundary condition, we can draw detailed abacus separating stable regions of unstable regions where bubbles appear. Then, we use the dispersion relations of this multidimensional linearized model, combined with the stationary phase theorem, to approach the profiles and the evolution of the bubbles appearing in unstable regimes, and verify that the obtained results adjust to the observations.
ERIC Educational Resources Information Center
Jones, Thomas A.
1983-01-01
Mathematical techniques used to solve geological problems are briefly discussed (including comments on use of geostatistics). Highlights of conferences/meetings and conference papers in mathematical geology are also provided. (JN)
Abbas, J J; Riener, R
2001-10-01
Systems that use electrical stimulation to activate paralyzed muscles, called "neuroprostheses", have restored important functional capabilities to many people with neurologic disorders such as spinal cord injury or stroke. However, the clinical benefits derived from neuroprostheses have been limited by the quality of control of posture and movement that has been achieved. Over the past few decades, engineers have used mathematical models and control systems technology to develop functional neuromuscular stimulation (FNS) control systems that show promise in the laboratory, but these have not yet been incorporated into practical solutions for clinical problems. This article briefly reviews several of the complicating factors in controlling FNS systems and describes the potential roles of biomechanical modeling and advanced control system technology. Three important challenges in FNS control systems research and development are identified: 1) to obtain an improved understanding of the biomechanical system that we are trying to control and how it is controlled by the intact neural system, 2) to develop new control system technology with a particular focus on strategies that mimic those used by biologic systems, and 3) to integrate the knowledge and technologies into useful systems that meet the needs of neuroprosthesis users. The outlook for the future includes many interesting problems; yet more importantly, it includes relevant clinical benefits to be gained through the application of biomechanical models and advanced control systems techniques in neuroprostheses.
Accuracy and Techniques in the Preparation of Mathematics Worksheets for Tactile Learners
ERIC Educational Resources Information Center
Rosenblum, L. Penny; Herzberg, Tina
2011-01-01
Data were gathered from 166 participants regarding their qualifications for and training in preparing mathematics materials for tactile learners. The participants shared information about the courses and workshops they had attended, the books and resources they used, the amount of time they spent preparing mathematics materials, and information…
Pagliaro, Claudia M; Kritzer, Karen L
2013-04-01
Over decades and across grade levels, deaf/hard-of-hearing (d/hh) student performance in mathematics has shown a gap in achievement. It is unclear, however, exactly when this gap begins to emerge and in what areas. This study describes preschool d/hh children's knowledge of early mathematics concepts. Both standardized and nonstandardized measures were used to assess understanding in number, geometry, measurement, problem solving, and patterns, reasoning and algebra. Results present strong evidence that d/hh students' difficulty in mathematics may begin prior to the start of formal schooling. Findings also show areas of strength (geometry) and weakness (problem solving and measurement) for these children. Evidence of poor foundational performance may relate to later academic achievement.
ERIC Educational Resources Information Center
Brizius, Martine G.; Luckey, Heather B.
This report summarizes the 1998 reporting year data on the National Science Foundation's (NSF's) Graduate Research Traineeship (GRT) program. The GRT program supports the research and education of talented students pursuing graduate degrees in critical and emerging areas of science, mathematics, engineering, and technology (SMET) and SMET…
Dumont, Y; Tchuenche, J M
2012-11-01
Chikungunya is an arthropod-borne disease caused by the Asian tiger mosquito, Aedes albopictus. It can be an important burden to public health and a great cause of morbidity and, sometimes, mortality. Understanding if and when disease control measures should be taken is key to curtail its spread. Dumont and Chiroleu (Math Biosc Eng 7(2):315-348, 2010) showed that the use of chemical control tools such as adulticide and larvicide, and mechanical control, which consists of reducing the breeding sites, would have been useful to control the explosive 2006 epidemic in Réunion Island. Despite this, chemical control tools cannot be of long-time use, because they can induce mosquito resistance, and are detrimental to the biodiversity. It is therefore necessary to develop and test new control tools that are more sustainable, with the same efficacy (if possible). Mathematical models of sterile insect technique (SIT) to prevent, reduce, eliminate or stop an epidemic of Chikungunya are formulated and analysed. In particular, we propose a new model that considers pulsed periodic releases, which leads to a hybrid dynamical system. This pulsed SIT model is coupled with the human population at different epidemiological states in order to assess its efficacy. Numerical simulations for the pulsed SIT, using an appropriate numerical scheme are provided. Analytical and numerical results indicate that pulsed SIT with small and frequent releases can be an alternative to chemical control tools, but only if it is used or applied early after the beginning of the epidemic or as a preventive tool.
Mathematical Methods in Counterterrorism: Tools and Techniques for a New Challenge
NASA Astrophysics Data System (ADS)
Hicks, David L.; Memon, Nasrullah; Farley, Jonathan D.; Rosenørn, Torben
Throughout the years mathematics has served as the most basic and fundamental tool employed by scientists and researchers to study and describe a wide variety of fields and phenomena. One of the most important practical application areas of mathematics has been for national defense and security purposes. For example, during the Second World War, the mathematical principles underlying game theory and cryptography played a very important role in military planning. Since that time, it has become clear that mathematics has an important role to play in securing victory in any global conflict, including the struggle faced by national security and law enforcement officials in the fight against those engaged in terrorism and other illicit activities.
Robust video communication by combining scalability and multiple description coding techniques
NASA Astrophysics Data System (ADS)
Wang, Huisheng; Ortega, Antonio
2003-05-01
Layered coding (LC) and multiple description coding (MDC) have been proposed as two different kinds of 'quality adaptation' schemes for video delivery over the current Internet or wireless networks. To combine the advantages of LC and MDC, we present a new approach -- Multiple Description Layered Coding (MDLC), to provide reliable video communication over a wider range of network scenarios and application requirements. MDLC improves LC in that it introduces redundancy in each layer so that the chance of receiving at least one description of base layer is greatly enhanced. Though LC and MDC are each good in limit cases (e.g., long end-to-end delay for LC vs. short delay for MDC), the proposed MDLC system can address intermediate cases as well. Same as a LC system with retransmission, the MDLC system can have a feedback channel to indicate which descriptions have been correctly received. Thus a low redundancy MDLC system can be implemented with our proposed runtime packet scheduling system based on the feedback information. The goal of our scheduling algorithm is to find a proper on-line packet scheduling policy to maximize the playback quality at the decoder. Previous work on scheduling algorithms has not considered multiple decoding choices due to the redundancy between data units, because of the increase in complexity involved in considering alternate decoding paths. In this paper, we introduce a new model of Directed Acyclic HyperGraph (DAHG) to represent the data dependencies among frames and layers, as well as the data correlation between descriptions. The impact of each data unit to others is represented by messages passing along the graph with updates based on new information received. Experimental results show that the proposed system provides more robust and efficient video communication for real-time applications over lossy packet networks.
Arealis, Georgios; Rodrigues, Joana Bento; Hope, Natalie; Levy, Ofer
2017-01-01
Background: Over the last 2 decades arthroscopic stabilization and Bankart repair has gained popularity due to the advances in materials and surgical techniques. Results of arthroscopic stabilization have been similar to open without the risks of it. The number of anchors used has been suggested to be very important in “spot-weld” arthroscopic stabilization however the “purse-string” technique (PST) can achieve similar results using only one anchor. We describe technique and long term results from using the PST and search the literature for other papers regarding PST. Methods: Between 2003 and 2013 a total of 193 patients were operated. Patients included those with anterior instability. Using PubMed relevant studies reporting results of PST were identified. Results: Mean follow up was 2 (range 0.5 to 3) years. 9 (4.7%) patients experienced recurrent instability. Almost all patients (97%) returned to their sporting and leisure activities and all professional athletes went back to the same sport. One more UK centre reported 6.1% recurrence in 114 patients at 4 years follow up. These results are similar to the published 11% recurrence of instability after “spot-weld” arthroscopic techniques at 11 years clinical follow-up. Conclusion: This study indicates that PST is safe and effective alternative method for the treatment of anterior shoulder instability. In this technique with one anchor simultaneous repair of labrum, creation of an anterior bumper and capsular shift can be achieved. It has the advantage of being cheaper, faster yet efficient with good long term results and leaves space for revision anchors in case of recurrence. PMID:28400885
NASA Astrophysics Data System (ADS)
Namba, Masanobu; Nishino, Ryohei
The purpose of this paper is to study the effect of neighboring blade rows on the unsteady aerodynamic response of oscillating cascade blades on the basis of a genuine three-dimensional model. To this end, mathematical formulations based on the lifting surface theory are developed for a pair of contra-rotating annular cascades of oscillating blades. The mechanism of frequency scattering of blade loadings and mode scattering of acoustic waves resulting from interaction between the blade rows in relative rotational motions is mathematically explained. Simultaneous integral equations for all frequency components of blade loadings are derived from the flow tangency condition on the blade surfaces of both blade rows. The validity of the computation codes is verified.
1982-05-01
CR-82-0i22-1 Reports Control Symbol OSD. 1366 41-~41,•) 1, ANALYSIS OF MULTIPLE SOURCE OBSCURANTS ON THE REALISTIC BATTLEFIELD (AMSORB) VOLLME I...PERIOD COVERED ANALYSIS O)F MULTIPLE SOURCE OBSCURANTS ON THE FnlRpr REALISIIC BATTLEFIELD (AMSORB)______________ VOLUME I - MATHEMATICAL MODELS AND...ROUTINES 102 4.1 Mixitng-Layer Analysis Routine 102 4.2 Battlefield Source Characteristics Routine 118 4.3 Dispersion Model Routines and Meteorological
Aksenov, L.N.; Bronshtein, A.P.; Zadorina, E.N.; Zagorets, A.M.; Makarov, G.N.; Polyakov, A.A.; Shlenskii, O.F.
1981-01-01
The determination of the most effective regimes for the thermal processing of solid fuels and the control of these processes requires a well-based selection of mathematical models for them. In the reported theoretical study, the question is considered of the possibility of using the traditional equations of chemical kinetics for describing the thermal degradation of the organic matter of coals. Various methods are proposed for the detemination of thermogravimetric curves. 14 refs.
Salman, Salam O; Fernandes, Rui P; Rawal, Sundeep R
2017-10-01
The aim of this report is to present a new technique using current technologic advances for immediate reconstruction and dental rehabilitation of segmental mandibular defects with a screw-retained prosthesis. One case is reviewed and a detailed review of surgical and prosthetic techniques used is presented. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
Total cysto-prostatectomy: Technique description and results in 2 dogs.
Bacon, Nicholas; Souza, Carlos H de M; Franz, Sarah
2016-02-01
We describe a novel technique for total cysto-prostatectomy, followed by uretero-urethral anastomosis in 2 dogs. The technique was successful and was performed without pubic osteotomy. Post-operative urinary tract infections may be a potentially serious event.
Gray, W.G.
2001-01-25
This project has contributed to the improved understanding and precise physical description of multiphase subsurface flow by combining theoretical derivation of equations, lattice Boltzmann modeling of hydrodynamics to identify characteristics and parameters, and simplification of field-scale equations to assess the advantages and disadvantages of the complete theory.
Liang, Zhiqing; Chen, Yong; Xu, Huicheng; Li, Yuyan; Wang, Dan
2010-11-01
The objectives of this study were to describe our laparoscopic nerve-sparing radical hysterectomy (LNSRH) technique and to assess the feasibility and safety of the procedure, as well as its impact on voiding function. We introduce a fascia space dissection technique in order to preserve the pelvic splanchnic nerve, the hypogastric nerve and the bladder branch of the inferior hypogastric plexus under magnification (×10.5) during laparoscopic radical hysterectomy (LRH) with pelvic lymphadenectomy. From October 2006 to November 2009, 163 consecutive patients with cervical cancer underwent laparoscopic radical hysterectomy (LRH) and pelvic lymphadenectomy, with 82 women undergoing LNSRH with fascia space dissection technique (LNSRH group) and 81 undergoing LRH (LRH group). Data from 163 patients were prospectively collected and compared. Post-operative assessment of bladder function included the following: the time to recover the ability to void spontaneously and to achieve a post-void residual urine (PVR) volume of less than 50 ml, with urination function graded. The laparoscopic nerve-sparing radical hysterectomy procedure was completed successfully and was conducted safely in all of the patients. There were no conversions to open surgery in the two groups. The median operative duration in the LNSRH and the LRH groups were 163.52±34.47 min and 132.13±31.42 min, respectively. Blood loss was 142.12±62.38 ml and 187.69±68.63 ml, respectively. The time taken to obtain a post-void residual urine volume of less than 50 ml after removal of the urethral catheter was 7.42±2.35 d (5-18 d) in LNSRH group and was 16.75±7.73 d (5-35 d) in LRH group (P<0.05). The bladder void function recovery to Grades 0-I was 76 (92.7%) for the LNSRH group and 59 (72.8%) for the LRH group. A mean follow-up of 22.3 (5-42) months was adhered to, and no patient had a recurrence or metastasis. The technique described in this preliminary study appears to be safe, feasible, and easy in our
NASA Technical Reports Server (NTRS)
Fortenbaugh, R. L.
1980-01-01
A mathematical model of a high performance airplane capable of vertical attitude takeoff and landing (VATOL) was developed. An off line digital simulation program incorporating this model was developed to provide trim conditions and dynamic check runs for the piloted simulation studies and support dynamic analyses of proposed VATOL configuration and flight control concepts. Development details for the various simulation component models and the application of the off line simulation program, Vertical Attitude Take-Off and Landing Simulation (VATLAS), to develop a baseline control system for the Vought SF-121 VATOL airplane concept are described.
Educational assessment of mathematics skills and abilities.
Bryant, B R; Rivera, D P
1997-01-01
Mathematics assessments play a valuable role in identifying students' strengths and weaknesses and in developing and monitoring instructional practice. Over the last century, mathematics assessment has been refined as math content has changed as a result of curriculum reform. Today, researchers and practitioners use various assessment techniques to (a) identify students who have mathematics learning disabilities (LD), (b) target individual strengths and weaknesses across mathematics areas, (c) document the effects of mathematics instruction in a remedial or special program, (d) identify strategies that students employ during math activities, (e) conduct research about the characteristics of students with math LD, and (f) examine the technical characteristics of mathematics tests. This article provides an historical overview of the development of mathematics assessment and a description of specific strategies for conducting math evaluations.
Kritzer, Karen L
2009-01-01
This study examined young deaf children's early informal/formal mathematical knowledge as measured by the Test of Early Mathematics Ability (TEMA-3). Findings from this study suggest that prior to the onset of formal schooling, young deaf children might already demonstrate evidence of academic delays. Of these 28 participants (4-6 years of age), for whom data were analyzed, none received a score on the TEMA-3, indicating above-"average" ability according to normative ranking. More than half of participants received scores substantially below average with 11 participants receiving scores a year or more behind normative age-equivalent scores. Upon more focused analysis, specific areas of difficulty were found to include word/story problems, skip counting (i.e., counting by twos, threes, etc.), number comparisons, the reading/writing of two to three digit numbers, and addition/subtraction number facts. A qualitative analysis of the answers participants gave and the behaviors they demonstrated while answering the test items was conducted and revealed possible explanations for why specific test items may have been challenging. Implications of findings for parents, early interventionists, and teachers of young deaf children are discussed.
Noorbhai, M Habib; Noakes, Timothy D
2016-10-01
One of the first principles of cricket batsmanship that is coached from a young age is to play with a straight bat. Limited studies to date have examined whether top international batsmen use this traditionally described technique. Accordingly, we performed a descriptive, observational study of the backlift technique adopted by 65 of the most successful batsmen of all time, based on their career averages, strike rate and runs scored. The batsmen were divided into two groups depending on whether they played the game before or after 1954. Surprisingly, more than 70% of these successful batsmen did not adopt the traditionally taught technique. Instead, they adopted a more looped action in which the initial movement of the bat was in the direction of the slips, and in extreme cases it was either towards the gully/point region or to have the face of the bat directed towards the off-side. This suggests that traditionally taught batting coaching techniques may hinder, rather than enhance future cricketing performance. Since the vast majority of cricketers are not coached in this technique, this finding probably indicates that this looped technique is likely a contributing factor to effective batsmanship.
NASA Astrophysics Data System (ADS)
Artese, G.; Fiaschi, S.; Di Martire, D.; Tessitore, S.; Fabris, M.; Achilli, V.; Ahmed, A.; Borgstrom, S.; Calcaterra, D.; Ramondini, M.; Artese, S.; Floris, M.; Menin, A.; Monego, M.; Siniscalchi, V.
2016-06-01
The Emilia Romagna Region (N-E Italy) and in particular the Adriatic Sea coastline of Ravenna, is affected by a noticeable subsidence that started in the 1950s, when the exploitation of on and off-shore methane reservoirs began, along with the pumping of groundwater for industrial uses. In such area the current subsidence rate, even if lower than in the past, reaches the -2 cm/y. Over the years, local Authorities have monitored this phenomenon with different techniques: spirit levelling, GPS surveys and, more recently, Differential Interferometric Synthetic Aperture Radar (DInSAR) techniques, confirming the critical situation of land subsidence risk. In this work, we present the comparison between the results obtained with DInSAR and GPS techniques applied to the study of the land subsidence in the Ravenna territory. With regard to the DInSAR, the Small Baseline Subset (SBAS) and the Coherent Pixel Technique (CPT) techniques have been used. Different SAR datasets have been exploited: ERS-1/2, ENVISAT, TerraSAR-X and Sentinel-1. Some GPS campaigns have been also carried out in a subsidence prone area. 3D vertices have been selected very close to existing persistent scatterers in order to link the GPS measurement results to the SAR ones. GPS data were processed into the International reference system and the comparisons between the coordinates, for the first 6 months of the monitoring, provided results with the same trend of the DInSAR data, even if inside the precision of the method.
Owens, Charles A. Bui, James T. Knuttinen, M.-Grace Emmanuel, Neelmini Carrillo, Tami C. Gaba, Ron C.
2011-02-15
We describe our experience with the use of the 'double-wire restraining' technique to assist in the removal of two retrievable inferior vena cava filters: one had been misplaced in the right brachiocephalic vein with apex perforation of the vessel wall, and the second filter had migrated cephalad to straddle across both renal veins. The 'double-wire restraining' technique consists of two stiff-shaft Glidewires (Terumo, Somerset, NJ) placed through the same introducer sheath and positioned on opposite sides of the filter. Both wires restrain the filter at the tip of the sheath as the sheath is advanced, thus allowing the operator to reposition the filter. This report details how this technique was used to realign two malpositioned filters and reposition the filter apices from their extravascular location, thus exposing them for ensnarement.
Measuring dynamic in-vivo elbow kinematics: description of technique and estimation of accuracy.
McDonald, Colin P; Moutzouros, Vasilios; Bey, Michael J
2012-12-01
The objectives of this study were to characterize the translational and rotational accuracy of a model-based tracking technique for quantifying elbow kinematics and to demonstrate its in vivo application. The accuracy of a model-based tracking technique for quantifying elbow kinematics was determined in an in vitro experiment. Biplane X-ray images of a cadaveric elbow were acquired as it was manually moved through flexion-extension. The 3D position and orientation of each bone was determined using model-based tracking. For comparison, the position and orientation of each bone was also determined by tracking the position of implanted beads with dynamic radiostereometric analysis. Translations and rotations were calculated for both the ulnohumeral and radiohumeral joints, and compared between measurement techniques. To demonstrate the in vivo application of this technique, biplane X-ray images were acquired as a human subject extended their elbow from full flexion to full extension. The in vitro validation demonstrated that the model-based tracking technique is capable of accurately measuring elbow motion, with reported errors averaging less than ±1.0 mm and ±1.0 deg. For the in vivo application, the carrying angle changed from an 8.3 ± 0.5 deg varus position in full flexion to an 8.4 ± 0.5 deg valgus position in full extension. Model-based tracking is an accurate technique for measuring in vivo, 3D, dynamic elbow motion. It is anticipated that this experimental approach will enhance our understanding of elbow motion under normal and pathologic conditions.
CAD/CAM silicone simulator for teaching cheiloplasty: description of the technique.
Zheng, Y; Lu, B; Zhang, J; Wu, G
2015-02-01
Techniques of virtual simulation have been used to teach junior surgeons how to do a cheiloplasty, but still do not meet the trainees' demands. We describe a CAD/CAM silicone simulator, which we made using several maxillofacial prosthetic techniques. An optical scanning system was used to collect the data about the cleft lip. Reverse engineering software was then used to build the virtual model, and this was processed in wax by machine. The definitive simulator was made with prosthetic silicone and extrinsic colourants. The surgical trainees practised the basic skills of cheiloplasty on the simulator, and proved its worth.
Garisto, Juan D.; Pimentel M., Edwin E.
2017-01-01
Abstract Background: Urachal cysts (UCs) are secondary to incomplete obliteration of the embryonic urachal duct and may become symptomatic when infected. Treatment is primarily surgical to excise the infected cyst. Surgical approaches include a lower midline laparotomy or minimally invasive (MI) techniques. Case: We present a case of a young male with an infected UC that was treated with a single-incision laparoscopy surgery. The operative technique is described. Conclusion: This approach is a safe and feasible option for the MI management of UCs. PMID:28164161
Mortimer, Duncan; Segal, Leonie
2008-01-01
Algorithms for converting descriptive measures of health status into quality-adjusted life year (QALY)--weights are now widely available, and their application in economic evaluation is increasingly commonplace. The objective of this study is to describe and compare existing conversion algorithms and to highlight issues bearing on the derivation and interpretation of the QALY-weights so obtained. Systematic review of algorithms for converting descriptive measures of health status into QALY-weights. The review identified a substantial body of literature comprising 46 derivation studies and 16 studies that provided evidence or commentary on the validity of conversion algorithms. Conversion algorithms were derived using 1 of 4 techniques: 1) transfer to utility regression, 2) response mapping, 3) effect size translation, and 4) "revaluing" outcome measures using preference-based scaling techniques. Although these techniques differ in their methodological/theoretical tradition, data requirements, and ease of derivation and application, the available evidence suggests that the sensitivity and validity of derived QALY-weights may be more dependent on the coverage and sensitivity of measures and the disease area/patient group under evaluation than on the technique used in derivation. Despite the recent proliferation of conversion algorithms, a number of questions bearing on the derivation and interpretation of derived QALY-weights remain unresolved. These unresolved issues suggest directions for future research in this area. In the meantime, analysts seeking guidance in selecting derived QALY-weights should consider the validity and feasibility of each conversion algorithm in the disease area and patient group under evaluation rather than restricting their choice to weights from a particular derivation technique.
Smith, Zachary A.; Armin, Sean; Raphael, Dan; Khoo, Larry T.
2011-01-01
Background: We describe a new posterior dynamic stabilizing system that can be used to augment the mechanics of the degenerating lumbar segment. The mechanism of this system differs from other previously described surgical techniques that have been designed to augment lumbar biomechanics. The implant and technique we describe is an extension-limiting one, and it is designed to support and cushion the facet complex. Furthermore, it is inserted through an entirely percutaneous technique. The purpose of this technical note is to demonstrate a novel posterior surgical approach for the treatment of lumbar degenerative. Methods: This report describes a novel, percutaneously placed, posterior dynamic stabilization system as an alternative option to treat lumbar degenerative disk disease with and without lumbar spinal stenosis. The system does not require a midline soft-tissue dissection, nor subperiosteal dissection, and is a truly minimally invasive means for posterior augmentation of the functional facet complex. This system can be implanted as a stand-alone procedure or in conjunction with decompression procedures. Results: One-year clinical results in nine individual patients, all treated for degenerative disease of the lower lumbar spine, are presented. Conclusions: This novel technique allows for percutaneous posterior dynamic stabilization of the lumbar facet complex. The use of this procedure may allow a less invasive alternative to traditional approaches to the lumbar spine as well as an alternative to other newly developed posterior dynamic stabilization systems. PMID:22145084
Two-Site Appendectomy in Children: Description of Technique and Outcomes.
Slater, Bethany J; Rothenberg, Steven S
2017-04-01
Laparoscopic appendectomy is one of the most common operations. Single-site appendectomy has been gaining popularity; however, it has certain disadvantages. The purpose of this study was to review the results of an essentially scarless laparoscopic appendectomy technique. A retrospective review of all patients who underwent two-site appendectomy for appendicitis between January 2015 and February 2016 was performed. For all cases, a 4 mm trocar and a 5 mm trocar were placed through an infraumbilical incision and a 3 mm trocar was placed in the suprapubic region. Fifty patients underwent appendectomy using this technique. The average age was 9.7 years (5-16 years) and average weight was 40 kg (15.7-73.3 kg). The classifications of appendicitis consisted of 32 simple, 5 suppurative, 4 gangrenous, and 8 perforated. The average operative time was 29 minutes (6-53 minutes) and average length of stay was 1.9 days (1-6 days). There were three minor complications, and all cases were completed with this technique, including in obese patients and for perforated appendicitis. All patients reported satisfaction with their postoperative cosmetic outcome. This technique allows for the main incision to be hidden at the umbilicus, creating an essentially scarless cosmetic result. The addition of a 3 mm suprapubic port leads to increased maneuverability of the instruments and better retraction of the appendix. It is also feasible in obese children and cases of perforated appendicitis.
Four-Corner Arthrodesis: Description of Surgical Technique Using Headless Retrograde Crossed Screws.
Mamede, João; Castro Adeodato, Sandro; Aquino Leal, Rafael
2017-04-01
Four-corner fusion has been shown to be a reliable option of treatment of wrist arthritis, but there is no consensus about which implant and surgical procedure should be used in the arthrodesis. The present study aimed to describe a surgical technique using 2 crossed screws as implants, inserted in a retrograde manner, and to demonstrate preliminary results of the use of the technique. A retrospective study was conducted using medical records and imaging tests (radiographs and computed tomography) of all 15 patients who underwent a standardized 4-corner fusion technique, between December 2011 and July 2015, in the Department of Hand Surgery of Instituto Nacional de Traumatologia e Ortopedia (INTO), Rio de Janeiro, Brazil. We collected data on the following variables: fusion rate, time to fusion, and percentage of patients who had any complications or needed another surgical procedure on the same wrist. All but one patient achieved fusion of arthrodesis. The average time to union was 5.54 months (SD = 3.84). Only the patient who developed nonunion of the 4-corner fusion required another surgery on the same wrist. The procedure described in this study demonstrated a low complication rate and high fusion rate, and can therefore be considered a reliable surgical technique for 4-corner fusion.
Salö, Martin; Järbur, Emil; Hambraeus, Mette; Ohlsson, Bodil; Stenström, Pernilla; Arnbjörnsson, Einar
2016-08-04
The aim of the study was to describe the technique of two-trocar laparoscopic appendectomy and compare the outcome between two- and three-trocar techniques in children. All children who underwent laparoscopic surgery for suspected appendicitis from 2006 to 2014 in a center for pediatric surgery were included in the study. Converted surgeries and patients with appendiceal abscess or concomitant intestinal obstruction were excluded. A total of 259 children underwent appendectomy with either two (35 %) or three (65 %) laparoscopic trocars according to the surgeons' preference and intraoperative judgment. Patient demographics, clinical symptoms, surgery characteristics, and complications were reviewed. The mean age of the children was 10.4 years (range, 1-14 years). The mean follow-up time was 41.2 months (SD ± 29.2). No significant differences in age, gender, weight, or signs and symptoms were found between the two- and three-trocar groups. The mean surgery time was significantly shorter in the two-trocar group (47 min) than in the three-trocar group (66 min; p < 0.001). The rates of surgical complications were 2 % vs. 4 %, (p = 0.501), and the rates of postoperative complications were 0 % vs. 5 % (p = 0.054), in the two- and three-trocar groups. The overall incidence of postoperative wound infection was low (<1 %) and did not differ between groups. Two-trocar laparoscopic appendectomy seems to be a safe and feasible technique with a low rate of postoperative wound infections. The present findings demonstrate that when the two-trocar technique could be applied, it is a good complement to the conventional three-trocar technique.
Bagnasco, Annamaria; Galaverna, Lucia; Aleo, Giuseppe; Grugnetti, Anna Maria; Rosa, Francesca; Sasso, Loredana
2016-01-01
In the literature we found many studies that confirmed our concerns about nursing students' poor maths skills that directly impact on their ability to correctly calculate drug dosages with very serious consequences for patient safety. The aim of our study was to explore where students had most difficulty and identify appropriate educational interventions to bridge their mathematical knowledge gaps. This was a quali-quantitative descriptive study that included a sample of 726 undergraduate nursing students. We identified exactly where students had most difficulty and identified appropriate educational interventions to bridge their mathematical knowledge gaps. We found that the undergraduate nursing students mainly had difficulty with basic maths principles. Specific learning interventions are needed to improve their basic maths skills and their dosage calculation skills. For this purpose, we identified safeMedicate and eDose (Authentic World Ltd.), only that they are only available in English. In the near future we hope to set up a partnership to work together on the Italian version of these tools. Copyright © 2015 Elsevier Ltd. All rights reserved.
Experimental Mathematics and Mathematical Physics
Bailey, David H.; Borwein, Jonathan M.; Broadhurst, David; Zudilin, Wadim
2009-06-26
One of the most effective techniques of experimental mathematics is to compute mathematical entities such as integrals, series or limits to high precision, then attempt to recognize the resulting numerical values. Recently these techniques have been applied with great success to problems in mathematical physics. Notable among these applications are the identification of some key multi-dimensional integrals that arise in Ising theory, quantum field theory and in magnetic spin theory.
NASA Technical Reports Server (NTRS)
Seinfeld, J. H. (Principal Investigator)
1982-01-01
The problem of the assimilation of remote sensing data into mathematical models of atmospheric pollutant species was investigated. The problem is posed in terms of the matching of spatially integrated species burden measurements to the predicted three dimensional concentration fields from atmospheric diffusion models. General conditions are derived for the "reconstructability' of atmospheric concentration distributions from data typical of remote sensing applications, and a computational algorithm (filter) for the processing of remote sensing data is developed.
NASA Technical Reports Server (NTRS)
Seinfeld, J. H. (Principal Investigator)
1982-01-01
The problem of the assimilation of remote sensing data into mathematical models of atmospheric pollutant species was investigated. The data assimilation problem is posed in terms of the matching of spatially integrated species burden measurements to the predicted three-dimensional concentration fields from atmospheric diffusion models. General conditions were derived for the reconstructability of atmospheric concentration distributions from data typical of remote sensing applications, and a computational algorithm (filter) for the processing of remote sensing data was developed.
Nayak, Sandeep P; Jayaprasad, Kiran
2017-06-01
Neck dissection leaves behind an aesthetically unacceptable scar over front of the neck. Various techniques, both endoscopic and robotic, have been tried to avoid this scar. Though comparatively more cases of robotic surgery are reported than endoscopic neck dissection, the cost and availability of robot precludes many patients from getting the benefit of minimally invasive neck dissection (MIND). We performed minimally invasive neck dissection for two carefully selected patients with early oral cancer and cN0. We used standard endoscopic equipment and ubiquitously available laparoscopic ports. We used gas insufflation to create the working space. Our results show that MIND is feasible and oncologically safe. The scars produced are aesthetically better than that of conventional open neck dissection. This procedure leaves no scars in the anterior aspect of the neck. This technique can be replicated at any center with endoscopic equipments without need for purchasing specialised retractors or a robot.
Maskow, Thomas; Babel, Wolfgang
2003-03-20
Efficiency and velocity of growth are key variables to consider when designing any microbial biotechnological process. Selection of the optimal strain and description of environmental effects on growth patterns require rapid information about relevant parameters. Calorimetry is particularly suitable for providing such data, provided it can simultaneously perform many measurements and the apparatus is as simple as possible. The simplest experimental set-up measures the heat flux of microorganisms growing in a static, sealed ampoule. But, how reliable and reproducible are the growth rates and growth yield coefficients obtained from such a system? To answer this question, the strain Halomonas halodenitrificans CCM 286(T) was grown on glycerol with nitrate as the terminal electron acceptor in a multi-channel isothermal heat conduction calorimeter in such a way that growth was predominantly influenced by availability of the oxidant. The time course of the heat fluxes up to the maximum attained was successfully modelled using integrated Monod kinetics. The reproducibility of the specific growth rate obtained was excellent (standard deviation less than 1% for a single measurement and less than 3% for a couple of measurements) and agreed well with figures reported in the literature. An Arrhenius-type model, consisting of one term for the activation and one for the inactivation of the microbial catalyst, was found to fit the whole specific growth rate versus temperature curve.
Kuru, Oğuzhan; Topuz, Samet; Şen, Serhat; İyibozkurt, Cem; Berkman, Sinan
2011-01-01
Objective To measure the feasibility of sentinel lymph node technique in endometrial cancer. Material and Methods The study was designed as a prospective non-randomized case-control trial. Between 2010–2011, in Istanbul University, Istanbul Medical Faculty, Gynecologic Oncology department, 26 patients who were preoperatively evaluated as endometrial cancer enrolled in the study. Patients’ detailed informed consent and ethics committee approval were obtained. Sentinel lymph node (SLN) detection rate was determined as the primary outcome. Sensitivity, specificity, positive and negative predictive values and particularly false negative results were determined as secondary outcomes. As a technique of SLN, injection of methylene blue to the subserosal myometrium of the uterine fundus via 5 cc syringe following peritoneal aspiration cytology procedure was obtained. Surgery was made after injection for an average of 5 minutes due to the physiological spread of the blue dye. Then, the standard protocol of hysterectomy was performed and the retroperitoneum was opened to perform lymphadenectomy. The presence of lymph node regions, and presence of a sentinel node was recorded on the trial record form. Positive staining nodes were sent separately for pathological examination. In the course of the study due to insufficient rate of staining, the technique has been changed to cervical and multiple uterine injections. Results As the primary outcome, an SLN positivity rate of 23% in 6 patients with a total of 8 lymph nodes were found. The remarkable finding was that in the first technique, the rate was 1/16 (6%), while the second technique, 5/10 (50%), respectively. The difference is statistically significant (p=0.001). In endometrial cancer stage I and II, secondary outcomes for sensitivity, specificity, positive predictive value, negative predictive value were 23%, 0%, 100%, 43%, respectively. Because there were no metastatic lymph nodes found, false negative rate was 0
NASA Technical Reports Server (NTRS)
Wong, K. W.
1974-01-01
In lunar phototriangulation, there is a complete lack of accurate ground control points. The accuracy analysis of the results of lunar phototriangulation must, therefore, be completely dependent on statistical procedure. It was the objective of this investigation to examine the validity of the commonly used statistical procedures, and to develop both mathematical techniques and computer softwares for evaluating (1) the accuracy of lunar phototriangulation; (2) the contribution of the different types of photo support data on the accuracy of lunar phototriangulation; (3) accuracy of absolute orientation as a function of the accuracy and distribution of both the ground and model points; and (4) the relative slope accuracy between any triangulated pass points.
Impression of multiple implants using photogrammetry: Description of technique and case presentation
Peñarrocha-Oltra, David; Agustín-Panadero, Rubén; Bagán, Leticia; Giménez, Beatriz
2014-01-01
Aim: To describe a technique for registering the positions of multiple dental implants using a system based on photogrammetry. A case is presented in which a prosthetic treatment was performed using this technique. Study Design: Three Euroteknika® dental implants were placed to rehabilitate a 55-year-old male patient with right posterior maxillary edentulism. Three months later, the positions of the implants were registered using a photogrammetry-based stereo-camera (PICcamera®). After processing patient and implant data, special abutments (PICabutment®) were screwed onto each implant. The PICcamera® was then used to capture images of the implant positions, automatically taking 150 images in less than 60 seconds. From this information a file was obtained describing the relative positions – angles and distances – of each implant in vector form. Information regarding the soft tissues was obtained from an alginate impression that was cast in plaster and scanned. A Cr-Co structure was obtained using CAD/CAM, and its passive fit was verified in the patient’s mouth using the Sheffield test and the screw resistance test. Results and Conclusions: Twelve months after loading, peri-implant tissues were healthy and no marginal bone loss was observed. The clinical application of this new system using photogrammetry to record the position of multiple dental implants facilitated the rehabilitation of a patient with posterior maxillary edentulism by means of a prosthesis with optimal fit. The prosthetic process was accurate, fast, simple to apply and comfortable for the patient. Key words:Dental implants, photogrammetry, dental impression technique, CAD/CAM. PMID:24608216
Lim, Hyunjoo; Kim, Jina; Li, Li; Lee, Aeri; Jeong, Junemoe; Ko, Jonghyeok; Lee, Sungin; Kweon, Oh-Kyeong; Kim, Wan Hee
2017-08-04
The aim of this study was to describe a ventral laparoscopic technique for bilateral medial iliac lymphadenectomy in dogs. Twelve intact male purpose-bred research dogs weighting less than 15 kg were positioned in dorsal recumbency, and a 3-portal technique was used. Bilateral dissection was performed with vessel-sealing devices while tilting the surgical table by up to 30° towards the contralateral side of the target medial iliac lymph node (MILN) without changing the surgeon's position. Using a ventral laparoscopic approach, bilateral MILNs were identified and excised in all dogs. The mean time for unilateral and bilateral MILN dissections were 9.7 ± 3.8 min and 21.0 ± 6.0 min, respectively. The mean times for the right and left MILN dissections were 10.8 ± 4.3 min and 9.8 ± 2.5 min, respectively. The mean total surgery time was 43.7 ± 7.7 min. In total, 26 MILNs were dissected. Several complications, including, mild to moderate capillary hemorrhage from perinodal fat and vessels (controlled laparoscopically), mild spleen trauma caused by the first trocar insertion, and capsular damage of MILNs, were observed. However, there were no other major complications. All MILN samples were evaluated and deemed suitable for histopathologic diagnosis. Laparoscopic excision of MILNs is a useful method of excisional biopsy for histopathologic diagnosis. Using this ventral laparoscopic approach with the 3-portal technique, bilateral MILN dissection suitable for obtaining histopathologic samples could be achieved in a short time in dogs weighing less than 15 kg.
Coburger, Jan; König, Ralph W; Scheuerle, Angelika; Engelke, Jens; Hlavac, Michal; Thal, Dietmar R; Wirtz, Christian Rainer
2014-01-01
Conventional curved or sector array ultrasound (cioUS) is the most commonly used intraoperative imaging modality worldwide. Although highly beneficial in various clinical applications, at present the impact of linear array intraoperative ultrasound (lioUS) has not been assessed for intracranial use. We provide a technical description to integrate an independent lioUS probe into a commercially available neuronavigation system and evaluate the use of navigated lioUS as a resection control in glioblastoma surgery. We performed a prospective study assessing residual tumor detection after complete microsurgical resection using either cioUS or lioUS in 15 consecutive patients. We compared the imaging findings of both ultrasound modalities in 44 sites surrounding the resection cavity. The respective findings were correlated with the histopathologic findings of tissue specimen obtained from those sites. Use of cioUS leaded to an additional resection in 9 patients, whereas lioUS detected residual tumor during all surgeries. A further resection was performed at 33 of 44 intraoperative sites (75%) based on results of lioUS alone. Resected tissue was solid tumor in 66% and infiltration zone in 34%. No false-positive or false-negative findings were seen using lioUS. There was no case of a tumor detection in cioUS combined with a negative finding in lioUS. The difference of imaging results between cioUS and lioUS was significant (sign test, P<0.001). lioUS can be used as a safe and precise tool for intracranial image-guided resection control of glioblastomas. It can be integrated in a commercially available navigation system and shows a significant higher detection rate of residual tumor compared with conventional cioUS. Copyright © 2014 Elsevier Inc. All rights reserved.
Single-incision-two port laparoscopic tubal ligation: A cost comparison and technique description
Taşdemir, Nicel; Abalı, Remzi; Çelik, Cem; Aksu, Erson; Akkuş, Didem
2015-01-01
Objective Laparoscopic surgery is the principal minimally invasive technique that is used for the treatment of gynecologic pathologies. The single-incision laparoscopic surgery (SILS) is another innovation in minimally invasive medicine. The cost of the procedure correlates with the fundamental materials used to access the abdominal cavity and utilize trocars. Material and Methods We applied the single-incision tubal ligation procedure to three patients. A 15–20-mm vertical incision was made in the umbilicus. Two trocars were inserted through the same incision at different fascial regions after insufflation of the abdomen. A 5-mm bipolar cautery was introduced through the accessory trocar, and the mid-portion of the tubes was coagulated and cut bilaterally. Results The postoperative periods of the three patients were uneventful. All patients were discharged on the day of surgery. No major or minor complications occurred. Conclusion The cost for the abdominal access will drop about 82%. When we consider the low pricing for the tubal ligation procedure, the single-incision technique will be more applicable by this method. Moreover, patients will have the advantages of single-incision laparoscopic surgery with low cost. PMID:25788846
Electromyogram (EMG) recordings from the subscapularis muscle: description of a technique.
Németh, G; Kronberg, M; Broström, L A
1990-01-01
Operative treatments for recurrent dislocation of the shoulder usually focus on the subscapularis muscle because it is supposed to contribute to the joint stability. It is of clinical interest to record the EMG from the subscapularis muscle in order to interpret its function. The purpose of the present study was to describe a safe and reliable route to reach the muscle, deeply located between the scapula and the thoracic cage, with fine-wire EMG electrodes. Twenty-four shoulders were investigated in 12 volunteers. A hypodermic needle containing bipolar fine-wire electrodes was inserted in the posterior axillary line with the subjects in the supine position, and the arm held in an abducted and externally rotated position. Three criteria confirmed the location of the electrodes: experience of periosteal pain when the needle reached the costal surface of the scapula, drawing-in of the wires 3-4 cm when the subject adducted his arm, thereby rotating his scapula downward, and raw EMG recorded during typical movements. Additionally, in four shoulders, the electrode location was checked with computed tomography. There were no complications from this technique, and the subjects felt no pain from the fine-wire electrodes during arm movements. We conclude that the described technique is a safe and reliable method of reaching the subscapularis muscle with EMG electrodes.
Two-step tunneling technique of deep brain stimulation extension wires-a description.
Fontaine, Denys; Vandersteen, Clair; Saleh, Christian; von Langsdorff, Daniel; Poissonnet, Gilles
2013-12-01
While a significant body of literature exists on the intracranial part of deep brain stimulation surgery, the equally important second part of the intervention related to the subcutaneous tunneling of deep brain stimulation extension wires is rarely described. The tunneling strategy can consist of a single passage of the extension wires from the frontal incision site to the subclavicular area, or of a two-step approach that adds a retro-auricular counter-incision. Each technique harbors the risk of intraoperative and postoperative complications. At our center, we perform a two-step tunneling procedure that we developed based on a cadaveric study. In 125 consecutive patients operated since 2002, we did not encounter any complication related to our tunneling method. Insufficient data exist to fully evaluate the advantages and disadvantages of each tunneling technique. It is of critical importance that authors detail their tunneling modus operandi and report the presence or absence of complications. This gathered data pool may help to formulate a definitive conclusions on the safest method for subcutaneous tunneling of extension wires in deep brain stimulation.
Kavallaris, Andreas; Chalvatzas, N; Kelling, K; Bohlmann, M K; Diedrich, K; Hornemann, A
2011-05-01
Hysterectomy remains the most common major gynecological operation. This is the first study that describes a new technique of TLH without using any kind of uterine manipulator or vaginal tube (TLHwM) and analyzes the intra- and postoperative surgical outcome of the first 67 cases. Between October 2008 and December 2009, 67 patients underwent TLH without uterine manipulator or vaginal tube. We analyzed the differences in the outcome by using three different kinds of surgical instruments: in 21 cases the TLHwM was performed using conventional 5 mm bipolar and scissors, in 22 cases using Sonosurgical, and in 24 cases using PKS cutting forceps. There was no intra- or postoperative complications. The overall mean operating time was by TLHwM with salpingo-oophorectomy 98 min and without salpingo-oophorectomy, 80 min. The mean operating time using cutting forceps was significantly lower. The mean uterine weight was 263 g. Uterine manipulator seems to be a safe and practical surgical method, especially for patients with vaginal stenosis and in cases of enlarged uterus. With its short operation time and no complication rate, we believe that this method is an enrichment of the laparoscopic hysterectomy techniques.
Peñarrocha-Oltra, David; Agustín-Panadero, Rubén; Bagán, Leticia; Giménez, Beatriz; Peñarrocha, María
2014-07-01
To describe a technique for registering the positions of multiple dental implants using a system based on photogrammetry. A case is presented in which a prosthetic treatment was performed using this technique. Three Euroteknika® dental implants were placed to rehabilitate a 55-year-old male patient with right posterior maxillary edentulism. Three months later, the positions of the implants were registered using a photogrammetry-based stereo-camera (PICcamera®). After processing patient and implant data, special abutments (PICabutment®) were screwed onto each implant. The PICcamera® was then used to capture images of the implant positions, automatically taking 150 images in less than 60 seconds. From this information a file was obtained describing the relative positions - angles and distances - of each implant in vector form. Information regarding the soft tissues was obtained from an alginate impression that was cast in plaster and scanned. A Cr-Co structure was obtained using CAD/CAM, and its passive fit was verified in the patient's mouth using the Sheffield test and the screw resistance test. Twelve months after loading, peri-implant tissues were healthy and no marginal bone loss was observed. The clinical application of this new system using photogrammetry to record the position of multiple dental implants facilitated the rehabilitation of a patient with posterior maxillary edentulism by means of a prosthesis with optimal fit. The prosthetic process was accurate, fast, simple to apply and comfortable for the patient.
A Description of the Revised ATHEANA (A Technique for Human Event Analysis)
FORESTER,JOHN A.; BLEY,DENNIS C.; COOPER,SUSANE; KOLACZKOWSKI,ALAN M.; THOMPSON,CATHERINE; RAMEY-SMITH,ANN; WREATHALL,JOHN
2000-07-18
This paper describes the most recent version of a human reliability analysis (HRA) method called ``A Technique for Human Event Analysis'' (ATHEANA). The new version is documented in NUREG-1624, Rev. 1 [1] and reflects improvements to the method based on comments received from a peer review that was held in 1998 (see [2] for a detailed discussion of the peer review comments) and on the results of an initial trial application of the method conducted at a nuclear power plant in 1997 (see Appendix A in [3]). A summary of the more important recommendations resulting from the peer review and trial application is provided and critical and unique aspects of the revised method are discussed.
Batagini, Nayara Cioffi; Hardy, David; Clair, Daniel G; Kirksey, Lee
2016-03-01
Clinical outcome reports document that from 30% to 60% of endovascular aneurysm repair procedures are performed outside of US Food and Drug Administration-approved Instruction for Use, or "off label." Endovascular aneurysm repair performed outside of Instruction for Use has a significantly higher rate of device failure, potentially requiring device reintervention and even planned or emergent explant. The Nellix device has the potential to reduce the rate of aneurysm device failure through its novel design. The objective of this article was to introduce the Nellix EndoVascular Aneurysm Sealing System and indications for use and describe the technique of implantation. We describe various modes of endovascular aneurysm repair failure and how the Nellix system can reduce these unplanned adverse outcomes. Additional clinical applications and theoretical shortcomings of endovascular aneurysm sealing devices are detailed. Copyright © 2016 Elsevier Inc. All rights reserved.
Computed tomography-ultrasound fusion brachytherapy: description and evolution of the technique.
Fuller, Donald B; Jin, Haoran
2007-01-01
In this manuscript, we describe our computed tomography (CT)-ultrasound (US) fusion prostate brachytherapy method and report the updated dosimetry result and trend. This cohort of 132 consecutive patients received CT-US fusion prostate brachytherapy from the first author (DBF) from December 2002 to August 2006. The technique consists of a hybrid preplanned and intraoperative dynamic dosimetry method, which initially delivers a standard preplanned source distribution, and then uses interval CT-based source identification dosimetry, fused to an identically spaced intraoperative US volume study series, to direct remedial sources that correct initial dosimetry deficiencies. The median and minimum prostate Day 0 prostate volume of interest receiving 100% of prescribed dose (V(100)) results in this patient cohort measured 98.26% and 92.61%, respectively, with all Day 0 prostate dose received by 90% of the volume of interest (D(90)) results exceeding 100% of the prescribed dose, and the maximum Day 0 prostate D(90) value measuring 128% of the prescribed dose. During the period of this analysis, a trend to the decreased quantity of dynamic remedial millicuries per case was identified, with the total sources decreasing from 116% to 106% of the preplanned level, resulting in minimal V(100) and D(90) decreases, while continuing to exceed the minimum Day 0 dosimetry requirements. CT-US fusion dynamic prostate brachytherapy represents a consistent prostate brachytherapy dosimetry delivery mechanism, creating a tight lower and upper bound to the final Day 0 prostate V(100) and D(90) parameters. The practice and pitfalls of this technique are discussed in detail.
Lerch, T D; Steppacher, S D; Liechti, E F; Siebenrock, K A; Tannast, M
2016-08-01
The Bernese periacetabular osteotomy (PAO) is a surgical technique for the treatment of (1) hip dysplasia and (2) femoroacetabular impingement due to acetabular retroversion. The aim of the surgery is to prevent secondary osteoarthritis by improvement of the hip biomechanics. In contrast to other pelvic osteotomies, the posterior column remains intact with this technique. This improves the inherent stability of the acetabular fragment and thereby facilitates postoperative rehabilitation. The birth canal remains unchanged. Through a shortened ilioinguinal incision, four osteotomies and one controlled fracture around the acetabulum are performed. The direction of acetabular reorientation differs for both indications while the sequence of the osteotomies remains the same. This surgical approach allows for a concomitant osteochondroplasty in the case of an aspherical femoral head-neck junction. The complication rate is relatively low despite the complexity of the procedure. The key point for a successful long term outcome is an optimal reorientation of the acetabulum for both indications. With an optimal reorientation and a spherical femoral head, the cumulative survivorship of the hip after 10 years is 80-90 %. For the very first 75 patients, the cumulative 20-year survivorship was 60 %. The preliminary evaluation of the same series at a 30-year follow-up still showed a survivorship of approximately 30 %. The PAO has become the standard procedure for the surgical therapy of hip dysplasia in adolescents and adults.
Borbás, Enikő; Sinkó, Bálint; Tsinman, Oksana; Tsinman, Konstantin; Kiserdei, Éva; Démuth, Balázs; Balogh, Attila; Bodák, Brigitta; Domokos, András; Dargó, Gergő; Balogh, György T; Nagy, Zsombor K
2016-11-07
The aim of this study was to investigate the impact of formulation excipients and solubilizing additives on dissolution, supersaturation, and membrane transport of an active pharmaceutical ingredient (API). When a poorly water-soluble API is formulated to enhance its dissolution, additives, such as surfactants, polymers, and cyclodextrins, have an effect not only on dissolution profile but also on the measured physicochemical properties (solubility, pKa, permeability) of the drug while the excipient is present, therefore also affecting the driving force of membrane transport. Meloxicam, a nonsteroidal anti-inflammatory drug, was chosen as a poorly water-soluble model drug and formulated in order to enhance its dissolution using solvent-based electrospinning. Three polyvinylpyrrolidone (PVP) derivatives (K30, K90, and VA 64), Soluplus, and (2-hydroxypropyl)-β-cyclodextrin were used to create five different amorphous solid dispersions of meloxicam. Through experimental design, the various formulation additives that could influence the characteristics of dissolution and permeation through artificial membrane were observed by carrying out a simultaneous dissolution-permeation study with a side-by-side diffusion cell, μFLUX. Although the dissolution profiles of the formulations were found to be very similar, in the case of Soluplus containing formulation the flux was superior, showing that the driving force of membrane transport cannot be simplified to the concentration gradient. Supersaturation gradient, the difference in degree of supersaturation (defined as the ratio of dissolved amount of the drug to its thermodynamic solubility) between the donor and acceptor side, was found to be the driving force of membrane transport. It was mathematically derived from Fick's first law, and experimentally proved to be universal on several meloxicam containing ASDs and DMSO stock solution.
Jens, Sjoerd Marquering, Henk A.; Koelemay, Mark J. W.; Reekers, Jim A.
2015-02-15
ObjectiveTo study the feasibility of 2D perfusion imaging in critical limb ischemia (CLI).Methods/ResultsPerfusion angiography is a new technology which was tested in 18 patients with CLI of the foot. A standardized protocol was used with a catheter placed at the mid-part of the popliteal artery, and a total of 9 cc of non-ionic iodinated contrast material was injected at a rate of 3 cc/sec. The technology is based on early cardiology research where iodinated contrast agents were used for imaging of cardiac perfusion. During the first pass of the contrast, there is a significant diffusion of the contrast agents into the interstitial space, particularly for non-ionic and low-molecular-weight compounds.DiscussionThe original angiography data can be used to make a time–density curve, which represents the actual perfusion of the foot in time. Angiographic perfusion imaging is a post-processing modality for which no extra contrast or radiation is needed. With this technique, it is possible to get more information about the perfusion status and microcirculation of the foot. This is a step toward functional imaging in CLI patients.
Laparoscopic splenectomy and nephrectomy in a rat model. Description of a new technique.
Giuffrida, M C; Marquet, R L; Kazemier, G; Wittich, P; Bouvy, N D; Bruining, H A; Bonjer, H J
1997-05-01
In experimental studies on the effects of laparoscopic procedures on tumor biology, a localized tumor model is desirable. The spleen and the kidney are preferable, because these organs are amenable to tumor placement and subsequent removal. This study describes the technique of laparoscopic splenectomy and nephrectomy in the rat model. Pneumoperitoneum was established by CO2 insufflation. Laparoscopic splenectomy involved two-handed dissection, intracorporeal ligation, and division of gastrosplenic attachments and hilar and short gastric vessels. Laparoscopic nephrectomy was done by intracorporeal ligation and division of the renal vessels and the ureter after mobilization of the kidney. Laparoscopic splenectomy was performed in six rats; laparoscopic nephrectomy was done in six rats. Operative time ranged from 45 to 90 min for splenectomy and from 40 to 65 min for nephrectomy. Postoperatively, two rats died from hemorrhage. Necropsy of the rats after 10 days revealed adhesion in three rats after splenectomy and in four rats after nephrectomy. Inflammatory processes were found around the silk ligatures in all rats after splenectomy; in two rats wound infections occurred at the port sites. Laparoscopic splenectomy and nephrectomy in the rat proved technically feasible and may provide new localized tumor models suitable to be used in further studies on the oncological effects of laparoscopic surgery.
Giordano, Vincenzo; Schatzker, Joseph; Kfuri, Mauricio
2017-07-01
High-energy fractures of the proximal tibia with extensive fragmentation of the posterior rim of the tibial plateau are challenging. This technique aims to describe a method on how to embrace the posterior rim of the tibial plateau by placing a horizontal precontoured one-third tubular plate wrapped around its corners. This method, which we named "hoop plating," is mainly indicated for cases of crushed juxta-articular rim fractures, aiming to restore cortical containment of the tibial plateau. Through a lateral approach with a fibular head osteotomy (Lobenhoffer approach), both anterolateral and posterolateral fragments are directly reduced and supported by a one-third tubular plate of adequate length. The plate is inserted from lateral to medial deep to all soft tissues, and its position is checked with fluoroscopy. The implant sits exactly on the posterior cortex of the tibial plateau and provides containment for the reduced juxta-articular posterior cortex and rim. We begin with immediate range of motion. Toe-touch weight-bearing with crutches is allowed with the operated knee in full extension. Weight-bearing is gradually increased only after 6 weeks as bone healing is taking place. Clinical follow-up is performed at 1, 3, 6, and 12 weeks. If the radiological exam confirms that the fracture is healed, the patient is allowed to proceed to muscle strengthening and bear weight entirely. The "hoop plating" may be a good option for the management in cases of extensive posterior tibial plateau articular surface fracture and impaction with rim and posterior cortical wall fragmentation. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
A new mathematical modelling based shape extraction technique for Forensic Odontology.
G, Jaffino; A, Banumathi; Gurunathan, Ulaganathan; B, Vijayakumari; J, Prabin Jose
2017-04-01
Forensic Odontology is a specific means for identifying a person in which deceased, and particularly in fatality incidents. The algorithm can be proposed to identify a person by comparing both postmortem (PM) and antemortem (AM) dental radiographs and photographs. This work aims to introduce a new mathematical algorithm for photographs in addition with radiographs. Isoperimetric graph partitioning method is used to extract the shape of dental images in forensic identification. Shape matching is done by comparing AM and PM dental images using both similarity and distance measures. Experimental results prove that the higher matching distance is observed by distance metric rather than similarity measures. The results of this algorithm show that a high hit rate is observed for distance based performance measures and it is well suited for forensic odontologist to identify a person. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
2011-01-01
Background Fluorescence in situ hybridization (FISH) is very accurate method for measuring HER2 gene copies, as a sign of potential breast cancer. This method requires small tissue samples, and has a high sensitivity to detect abnormalities from a histological section. By using multiple colors, this method allows the detection of multiple targets simultaneously. The target parts in the cells become visible as colored dots. The HER-2 probes are visible as orange stained spots under a fluorescent microscope while probes for centromere 17 (CEP-17), the chromosome on which the gene HER-2/neu is located, are visible as green spots. Methods The conventional analysis involves the scoring of the ratio of HER-2/neu over CEP 17 dots within each cell nucleus and then averaging the scores for a number of 60 cells. A ratio of 2.0 of HER-2/neu to CEP 17 copy number denotes amplification. Several methods have been proposed for the detection and automated evaluation (dot counting) of FISH signals. In this paper the combined method based on the mathematical morphology (MM) and inverse multifractal (IMF) analysis is suggested. Similar method was applied recently in detection of microcalcifications in digital mammograms, and was very successful. Results The combined MM using top-hat and bottom-hat filters, and the IMF method was applied to FISH images from Molecular Biology Lab, Department of Pathology, Wielkoposka Cancer Center, Poznan. Initial results indicate that this method can be applied to FISH images for the evaluation of HER2/neu status. Conclusions Mathematical morphology and multifractal approach are used for colored dot detection and counting in FISH images. Initial results derived on clinical cases are promising. Note that the overlapping of colored dots, particularly red/orange dots, needs additional improvements in post-processing. PMID:21489192
Fluoroscopy-Guided Sacroiliac Joint Injection: Description of a Modified Technique.
Kasliwal, Prasad Jaychand; Kasliwal, Sapana
2016-02-01
Sacroiliac joint (SIJ) pathology is a common etiologic cause for 10 - 27% of cases of mechanical low back pain (LBP) below the L5 level. In the absence of definite clinical or radiologic diagnostic criteria, controlled blocks of the SIJ have become the choice assessment method for making the diagnosis of SIJ pain. The SI joint is most often characterized as a large, auricular-shaped, diarthrodial synovial joint. In reality, its synovial characteristic is limited only to the distal third and anterior third. In SIJ interventions, the lateral view has been underutilized. In our technique, we used the lateral view to create a three-dimensional view of the SIJ to aid in gauging the accurateness of the contrast spread and to obtain a precise block. After obtaining appropriate fluoroscopic images, a curved tip spinal needle was directed into the inferior aspect of the SIJ using a posterior approach. As the needle contacts firm tissues on the posterior aspect of the joint, position of the needle tip is checked using lateral fluoroscopy. In the lateral view, the needle tip position is manipulated to keep it in the anterior third of the SIJ and contrast is injected. Our criteria for accurate SIJ block, in posteroanterior (PA) view, is the injection of the contrast medium should outline the joint space and the contrast medium should be seen to travel cephalad along the joint line. In the lateral view, the contrast medium most densely outlines the parameter of the joint. We have utilized this method with good effect in approximately 30 cases over one year. Out of 30 cases, needle position and contrast spread was satisfactory in 28 and 27 cases, respectively. So satisfactory needle placement and contrast spread was in 93% and 87% cases. Pain relief of 80% or more after intra-articular injection of local anesthetic was seen in 50% (15 of 30) patients; pain relief of 50 - 79% was witnessed in 30% (9 of 30) patients. Thus, pain decreased 50% or more in 80% (24 of 30) of the joints
Taggart, Peter; Srinivasan, Neil; Hayward, Martin; Lambiase, Pier D.
2016-01-01
Background The restitution of the action potential duration (APDR) and conduction velocity (CVR) are mechanisms whereby cardiac excitation and repolarization adapt to changes in heart rate. They modulate the vulnerability to dangerous arrhythmia, but the mechanistic link between restitution and arrhythmogenesis remains only partially understood. Methods This paper provides an experimental and theoretical study of repolarization and excitation restitution properties and their interactions in the intact human epicardium. The interdependence between excitation and repolarization dynamic is studied in 8 patients (14 restitution protocols, 1722 restitution curves) undergoing global epicardial mapping with multi-electrode socks before open heart surgery. A mathematical description of the contribution of both repolarization and conduction dynamics to the steepness of the APDR slope is proposed. Results This study demonstrates that the APDR slope is a function of both activation and repolarization dynamics. At short cycle length, conduction delay significantly increases the APDR slope by interacting with the diastolic interval. As predicted by the proposed mathematical formulation, the APDR slope was more sensitive to activation time prolongation than to the simultaneous shortening of repolarization time. A steep APDR slope was frequently identified, with 61% of all cardiac sites exhibiting an APDR slope > 1, suggesting that a slope > 1 may not necessarily promote electrical instability in the human epicardium. APDR slope did not change for different activation or repolarization times, and it was not a function of local baseline APD. However, it was affected by the spatial organization of electrical excitation, suggesting that in tissue APDR is not a unique function of local electrophysiological properties. Spatial heterogeneity in both activation and repolarization restitution contributed to the increase in the modulated dispersion of repolarization, which for short cycle
A Step-by-Step Teaching Technique for Teachers with Adult Students of Mathematics
ERIC Educational Resources Information Center
McDonald, Betty
2013-01-01
Step-by-step teaching is a researcher-designed innovative process that takes the adult learner, step-by-step, from his present level of understanding to the required level. The technique is based on well-researched and accepted pedagogical practices set in their psychological, sociological, and andragogical perspectives. Using a convenience sample…
ERIC Educational Resources Information Center
Idowu, Olumuyiwa Ayodeji
2013-01-01
Over the past 2 years, almost 45% of the students attending a local suburban high school failed Algebra 2. The purpose of this study was to compare the impact of a cooperative instructional technique (student teams-achievement divisions [STAD]) to traditional instructional methods on performance in high school algebra. Motivational and cognitive…
ERIC Educational Resources Information Center
Idowu, Olumuyiwa Ayodeji
2013-01-01
Over the past 2 years, almost 45% of the students attending a local suburban high school failed Algebra 2. The purpose of this study was to compare the impact of a cooperative instructional technique (student teams-achievement divisions [STAD]) to traditional instructional methods on performance in high school algebra. Motivational and cognitive…
Boix, Macarena; Cantó, Begoña
2013-04-01
Accurate image segmentation is used in medical diagnosis since this technique is a noninvasive pre-processing step for biomedical treatment. In this work we present an efficient segmentation method for medical image analysis. In particular, with this method blood cells can be segmented. For that, we combine the wavelet transform with morphological operations. Moreover, the wavelet thresholding technique is used to eliminate the noise and prepare the image for suitable segmentation. In wavelet denoising we determine the best wavelet that shows a segmentation with the largest area in the cell. We study different wavelet families and we conclude that the wavelet db1 is the best and it can serve for posterior works on blood pathologies. The proposed method generates goods results when it is applied on several images. Finally, the proposed algorithm made in MatLab environment is verified for a selected blood cells.
A method for digital image registration using a mathematical programming technique
NASA Technical Reports Server (NTRS)
Yao, S. S.
1973-01-01
A new algorithm based on a nonlinear programming technique to correct the geometrical distortions of one digital image with respect to another is discussed. This algorithm promises to be superior to existing ones in that it is capable of treating localized differential scaling, translational and rotational errors over the whole image plane. A series of piece-wise 'rubber-sheet' approximations are used, constrained in such a manner that a smooth approximation over the entire image can be obtained. The theoretical derivation is included. The result of using the algorithm to register four channel S065 Apollo IX digitized photography over Imperial Valley, California, is discussed in detail.
NASA Astrophysics Data System (ADS)
Gouda, M. M.; Hamzawy, A.; Badawi, M. S.; El-Khatib, A. M.; Thabet, A. A.; Abbas, M. I.
2016-02-01
The full-energy peak efficiency of high-purity germanium well-type detector is extremely important to calculate the absolute activities of natural and artificial radionuclides for samples with low radioactivity. In this work, the efficiency transfer method in an integral form is proposed to calculate the full-energy peak efficiency and to correct the coincidence summing effect for a high-purity germanium well-type detector. This technique is based on the calculation of the ratio of the effective solid angles subtended by the well-type detector with cylindrical sources measured inside detector cavity and an axial point source measured out the detector cavity including the attenuation of the photon by the absorber system. This technique can be easily applied in establishing the efficiency calibration curves of well-type detectors. The calculated values of the efficiency are in good agreement with the experimental calibration data obtained with a mixed γ-ray standard source containing 60Co and 88Y.
NASA Technical Reports Server (NTRS)
Gassaway, J. D.; Mahmood, Q.; Trotter, J. D.
1978-01-01
A system was developed for depositing aluminum and aluminum alloys by the D.C. sputtering technique. This system which was designed for a high level of cleanliness and ion monitoring the deposition parameters during film preparation is ready for studying the deposition and annealing parameters upon double level metal preparation. The finite element method was studied for use in the computer modeling of two dimensional MOS transistor structures. An algorithm was developed for implementing a computer study which is based upon the finite difference method. The program was modified and used to calculate redistribution data for boron and phosphorous which had been predeposited by ion implantation with range and straggle conditions typical of those used at MSFC. Data were generated for 111 oriented SOS films with redistribution in N2, dry O2 and steam ambients. Data are given showing both two dimensional effects and the evolution of the junction depth, sheet resistance and integrated dose with redistribution time.
Mathematical descriptions of indeterminate growth.
Powell, Christopher D; López, Secundino; Dumas, André; Bureau, Dominique P; Hook, Sarah E; France, James
2017-07-21
Two models were derived in an effort to better describe the indeterminate nature of growth exhibited by ectotherms. The models are characterized by their non-sigmoidal shape and are based on three assumptions: quantity of growth machinery works at a rate dependent on feed intake; the relationship between growth rate and intake level follows the law of diminishing returns; and growth is irreversible. The Michaelis-Menten and Mitscherlich equations are used in their formulation. To investigate their potential, the models were fitted to six datasets, representing repeated measures of live body weights of two species: rainbow trout (Oncorhynchus mykiss) and Nile tilapia (Oreochromis niloticus). The models were evaluated on the basis of fitting behaviour, examination of residuals, along with measures of goodness-of-fit. Agreement between predicted and observed body weights, and flexibility to mimic growth patterns given varying species and culture conditions, affirm the ability of both models to describe indeterminate growth in fish. Copyright © 2017 Elsevier Ltd. All rights reserved.
Mathematical expression of discharge capacity of compound open channels using MARS technique
NASA Astrophysics Data System (ADS)
Parsaie, Abbas; Haghiabi, Amir Hamzeh
2017-03-01
In this paper, analytical methods, artificial neural network (ANN) and multivariate adaptive regression splines (MARS) techniques were utilised to estimate the discharge capacity of compound open channels (COC). To this end, related datasets were collected from literature. The results showed that the divided channel method with a coefficient of determination ( R 2) value of 0.76 and root mean square error (RMSE) value of 0.162 has the best performance, among the various analytical methods tested. The performance of applied soft computing models with R 2=0.97 and RMSE = 0.03 was found to be more accurate than analytical approaches. Comparison of MARS with the ANN model, in terms of developed discrepancy ratio (DDR) index, showed that the accuracy of MARS model was better than that of MLP model. Reviewing the structure of the derived MARS model showed that the longitudinal slope of the channel ( S), relative flow depth ( H r ) and relative area ( A r ) have a high impact on modelling and forecasting the discharge capacity of COCs.
ERIC Educational Resources Information Center
Livne, Nava L.; Milgram, Roberta M.
2000-01-01
A questionnaire of out-of-school activities was developed to assess mathematical creative ability at four levels using a three-stage circular technique. Israeli high school students (n=139) reported whether they had performed the activities. Resulting data provided evidence of the construct validity of a 12-item scale for assessing creative…
USDA-ARS?s Scientific Manuscript database
Pest control managers can benefit from using mathematical approaches, particularly models, when implementing area-wide pest control programs that include sterile insect technique (SIT), especially when these are used to calculate required rates of sterile releases to result in suppression or eradica...
NASA Technical Reports Server (NTRS)
Buckey, J. C.; Beattie, J. M.; Gaffney, F. A.; Nixon, J. V.; Blomqvist, C. G.
1984-01-01
Accurate, reproducible, and non-invasive means for ventricular volume determination are needed for evaluating cardiovascular function zero-gravity. Current echocardiographic methods, particularly for the right ventricle, suffer from a large standard error. A new mathematical approach, recently described by Watanabe et al., was tested on 1 normal formalin-fixed human hearts suspended in a mineral oil bath. Volumes are estimated from multiple two-dimensional echocardiographic views recorded from a single point at sequential angles. The product of sectional cavity area and center of mass for each view summed over the range of angles (using a trapezoidal rule) gives volume. Multiple (8-14) short axis right ventricle and left ventricle views at 5.0 deg intervals were videotaped. The images were digitized by two independent observers (leading-edge to leading-edge technique) and analyzed using a graphics tablet and microcomputer. Actual volumes were determined by filling the chambers with water. These data were compared to the mean of the two echo measurements.
ERIC Educational Resources Information Center
Locklear, Tonja Motley
2012-01-01
The Sources of Middle School Mathematics Self-Efficacy Scale (Usher & Pajares, 2009) was adapted for use in this study investigating the impact that gender, race, sexual orientation, hometown location (rural, suburban, or urban), high school GPA, college GPA and letter grade of a mathematics course in the previous semester had on the four…
ERIC Educational Resources Information Center
Afzal, Muhammad Tanveer; Gondal, Bashir; Fatima, Nuzhat
2014-01-01
The major objective of the study was to elicit the effect of three instructional methods for teaching of mathematics on low, average and high achiever elementary school students. Three methods: traditional instructional method, computer assisted instruction (CAI) and teacher facilitated mathematics learning software were employed for the teaching…
ERIC Educational Resources Information Center
Idil, Feriha Hande; Narli, Serkan; Aksoy, Esra
2016-01-01
The aim of this study is to examine middle school students' attitude towards mathematics in the context of their mathematic learning preferences using data mining which is data analysis methodology that has been successfully used in different areas including educational domains. "How do I actually learn?" questionnaire and attitude scale…
Chilvarquer, I; McDavid, W D; Langlais, R P; Chilvarquer, L W; Nummikoski, P V
1988-05-01
A new technique for imaging the temporomandibular joint with rotational panoramic radiography is explained and demonstrated with a tissue-equivalent phantom. In this technique the patient is displaced forward and laterally away from the side under examination. Radiographs made with the proposed technique show the temporomandibular joint with more sharpness and less distortion than do radiographs made with conventional panoramic techniques.
Changing Mathematics Education in Mozambique.
ERIC Educational Resources Information Center
Gerdes, Paulus
1981-01-01
A brief description and analysis of mathematics education in different phases of the history of Mozambique are provided. Particular attention is given to teacher training and the first National Seminar on the Teaching of Mathematics. (MP)
Mathematical and statistical analysis
NASA Technical Reports Server (NTRS)
Houston, A. Glen
1988-01-01
The goal of the mathematical and statistical analysis component of RICIS is to research, develop, and evaluate mathematical and statistical techniques for aerospace technology applications. Specific research areas of interest include modeling, simulation, experiment design, reliability assessment, and numerical analysis.
ERIC Educational Resources Information Center
Hadlock, Charles R
2013-01-01
The movement of groundwater in underground aquifers is an ideal physical example of many important themes in mathematical modeling, ranging from general principles (like Occam's Razor) to specific techniques (such as geometry, linear equations, and the calculus). This article gives a self-contained introduction to groundwater modeling with…
ERIC Educational Resources Information Center
Hadlock, Charles R
2013-01-01
The movement of groundwater in underground aquifers is an ideal physical example of many important themes in mathematical modeling, ranging from general principles (like Occam's Razor) to specific techniques (such as geometry, linear equations, and the calculus). This article gives a self-contained introduction to groundwater modeling with…
USDA-ARS?s Scientific Manuscript database
We describe and illustrate two techniques for enhancing curatorial and processing efficiency as it pertains to parasitic Hymenoptera (Chalcidoidea, Cynipoidea). These techniques were developed in response not only to the massive number of parasitoids that have been acquired through our and others’ ...
Learning Together: Mathematics
ERIC Educational Resources Information Center
Her Majesty's Inspectorate of Education, 2010
2010-01-01
This guide is intended to stimulate professional reflection, dialogue and debate about mathematics and how to improve it. It draws together themes, features and characteristics of effective improvement in mathematics and descriptions of good practice. It offers a reference point for staff and teachers who are working together to improve…
Wood, Caroline E; Hardeman, Wendy; Johnston, Marie; Francis, Jill; Abraham, Charles; Michie, Susan
2016-06-07
Behaviour change interventions are likely to be reproducible only if reported clearly. We assessed whether the behaviour change technique taxonomy version 1 (BCTTv1), with and without training in identifying BCTs, improves the clarity and replicability of written reports of observed behaviour change interventions. Three studies assessed effects of using and training in the use of BCTTv1 on the clarity and replicability of intervention descriptions written after observing videos of smoking cessation interventions. Study 1 examined the effects of using and not using BCTTv1. Study 2 examined the effects of using BCTTv1 and training in use of BCTTv1 compared no use and no training. Study 3 employed a within-group design to assess change in descriptions written before and after training. One-hundred and 66 'writers' watched videos of behaviour change interventions and wrote descriptions of the active components delivered. In all studies, the participants' written descriptions were evaluated by (i) 12 'raters' (untrained in BCTTv1) for clarity and replicability and (ii) 12 'coders' (trained in BCTTv1) for reliability of BCT coding. Writers rated the usability and accessibility of using BCTTv1 to write descriptions. Ratings of clarity and replicability did not differ between groups in study 1 (all ps > 0.05), were poorer for trained users in study 2 (all ps < 0.01) and improved following training in study 3 (all ps < 0.05). BCT identification was more reliable from descriptions written by trained BCTTv1 users (p < 0.05; study 2) but not simple use of BCTTv1 (p = 0.93; study 1) or by writers who had written a description without BCTTv1, before training (p = 0.50; study 3). Writers reported that using BCTTv1 was difficult but 'useful', 'good' and 'desirable' and that their descriptions would be clear and replicable (all means above mid-point of the scale). Effects of training to use BCTTv1 on the quality of written reports of observed interventions
The relation between learning mathematics and students' competencies in undesrtanding texts
NASA Astrophysics Data System (ADS)
Hapipi, Azmi, Syahrul; Sripatmi, Amrullah
2017-08-01
This study was a descriptive study that aimed to gain an overview on the relation between learning mathematics and students' competencies in understanding texts. This research was classified as an ex post facto study due in part to the variable studied is the variable that was already happening. While the technique of taking the sample using stratified proportional sampling techniques. These techniques have been selected for the condition of the population, in the context of learning mathematics, diverse and also tiered. The results of this study indicate that there is a relationship between learning mathematics and students' competencies in understanding texts.
NASA Technical Reports Server (NTRS)
Dieudonne, J. E.
1978-01-01
A numerical technique was developed which generates linear perturbation models from nonlinear aircraft vehicle simulations. The technique is very general and can be applied to simulations of any system that is described by nonlinear differential equations. The computer program used to generate these models is discussed, with emphasis placed on generation of the Jacobian matrices, calculation of the coefficients needed for solving the perturbation model, and generation of the solution of the linear differential equations. An example application of the technique to a nonlinear model of the NASA terminal configured vehicle is included.
ERIC Educational Resources Information Center
Manning, S.; Dix, A.
2008-01-01
There is anecdotal evidence that a significant number of students studying computing related courses at degree level have difficulty with sub-GCE mathematics. Testing of students' skills is often performed using diagnostic tests and a number of computer-based diagnostic tests exist, which work, essentially, by testing one specific diagnostic skill…
ERIC Educational Resources Information Center
Manning, S.; Dix, A.
2008-01-01
There is anecdotal evidence that a significant number of students studying computing related courses at degree level have difficulty with sub-GCE mathematics. Testing of students' skills is often performed using diagnostic tests and a number of computer-based diagnostic tests exist, which work, essentially, by testing one specific diagnostic skill…
Badani, Ketan K; Rothberg, Michael B; Bergman, Ari; Silva, Mark V; Shapiro, Edan Y; Nieder, Alan; Patel, Trushar; Bhandari, Akshay
2014-09-01
Nephroureterectomy (NUx) with full bladder cuff excision is the gold-standard treatment for upper urinary tract urothelial cancer. Although minimally invasive techniques for NUx have demonstrated comparable outcomes to those of the open technique, the robotic technique is limited by the need for intraoperative patient repositioning and robot redocking to manage the distal ureter and bladder cuff. We describe our novel technique of robotic NUx that allows for complete access to the kidney and full bladder cuff excision. This modified technique was performed on a consecutive series of patients undergoing robotic NUx for upper urinary tract urothelial cancer from August 2012 to January 2014. Operative parameters and pathologic data were recorded, and patients were followed up for surveillance. After insufflation, the robotic trocars are placed in a standardized fashion, allowing for a one-time switch of instruments to facilitate distal ureteral dissection and a wide bladder cuff excision without patient repositioning or robot redocking. Twenty-six patients have undergone NUx using our modified technique. Mean blood loss and operative time were 66 mL and 230 minutes, respectively. There were no intraoperative complications or open conversions, and there were no positive surgical margins. The average follow-up time was 7.8 months (range, 2-17 months), and 4 cases of cancer recurrence in the bladder were identified. This novel technique for robotic NUx offers a standardized and easy-to-implement approach for NUx that requires a minimal learning curve for an experienced robotic surgeon, while affording a comparable oncologic control without the need for patient repositioning or additional port placement.
NASA Astrophysics Data System (ADS)
Alanis Pena, Antonio Alejandro
Major commercial electricity generation is done by burning fossil fuels out of which coal-fired power plants produce a substantial quantity of electricity worldwide. The United States has large reserves of coal, and it is cheaply available, making it a good choice for the generation of electricity on a large scale. However, one major problem associated with using coal for combustion is that it produces a group of pollutants known as nitrogen oxides (NO x). NOx are strong oxidizers and contribute to ozone formation and respiratory illness. The Environmental Protection Agency (EPA) regulates the quantity of NOx emitted to the atmosphere in the United States. One technique coal-fired power plants use to reduce NOx emissions is Selective Catalytic Reduction (SCR). SCR uses layers of catalyst that need to be added or changed to maintain the required performance. Power plants do add or change catalyst layers during temporary shutdowns, but it is expensive. However, many companies do not have only one power plant, but instead they can have a fleet of coal-fired power plants. A fleet of power plants can use EPA cap and trade programs to have an outlet NOx emission below the allowances for the fleet. For that reason, the main aim of this research is to develop an SCR management mathematical optimization methods that, with a given set of scheduled outages for a fleet of power plants, minimizes the total cost of the entire fleet of power plants and also maintain outlet NO x below the desired target for the entire fleet. We use a multi commodity network flow problem (MCFP) that creates edges that represent all the SCR catalyst layers for each plant. This MCFP is relaxed because it does not consider average daily NOx constraint, and it is solved by a binary integer program. After that, we add the average daily NOx constraint to the model with a schedule elimination constraint (MCFPwSEC). The MCFPwSEC eliminates, one by one, the solutions that do not satisfy the average daily
Wadenya, Rose; Fulcher, Megan; Grunwald, Tal; Nussbaum, Burton; Grunwald, Zvi
2010-01-01
Fibrodysplasia ossificans progressiva (FOP) is a rare and debilitating genetic disorder of skeletal malformations and progressive heterotopic ossification. Flare-ups are episodic, with bone formation in skeletal muscle and connective tissue leading to ankylosis of major joints of the axial and appendicular skeleton. This report outlines the management of a patient with FOP who had ankylosis of the temporomandibular joint and progressive ossification of the neck structures. The patient underwent two different surgical and anesthetic procedures within a 10-year period to manage his oral pain. The authors compare the surgical techniques, osteotomy versus the more conservative buccal approach, anesthesia techniques, and conventional intubation versus sedated fiberoptic intubation. This report emphasizes the importance of a less invasive surgical technique and an appropriate anesthetic management that reduces the risks, cost, and morbidity associated with routine surgical management of patients with FOP.
ERIC Educational Resources Information Center
Roman, Charles Vasile
This study surveys speech-making practices and attitudes of practitioners in firms not primarily engaged in providing public relations services. Questionnaires designed to assess the uses of speech making as a public relations technique were sent to the 50 largest United States advertising agencies and to the 34 largest United States business and…
Domínguez, I; Luque, R; Noriega, M; Rey, J; Alía, J; Urda, A; Marco, F
2017-09-06
The prevalence of adult spinal deformity has been increasing exponentially over time. Surgery has been credited with good radiological and clinical results. The incidence of complications is high. MIS techniques provide good results with fewer complications. This is a retrospective study of 25 patients with an adult spinal deformity treated by MIS surgery, with a minimum follow-up of 6 months. Radiological improvement was SVA from 5 to 2cm, coronal Cobb angle from 31° to 6°, and lumbar lordosis from 18° to 38°. All of these parameters remained stable over time. We also present the complications that appeared in 4 patients (16%). Only one patient needed reoperation. We describe the technique used and review the references on the subject. We conclude that the MIS technique for treating adult spinal deformity has comparable results to those of the conventional techniques but with fewer complications. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.
NASA Astrophysics Data System (ADS)
Hamilton, N. R.; Williamson, D. M.; Lewis, D.; Glauser, A.; Jardine, A. P.
2017-01-01
It has been shown experimentally that under many circumstances the strength limiting factor of Polymer Bonded Explosives (PBXs) is the adhesion which exists between the filler crystals and the polymer matrix. Experimental measurements of the Work of Adhesion between different binders and glass have been conducted using the JKR experimental technique, a reversible axisymmetric fracture experiment, during which the area of contact and the applied force are both measured during loading and unloading of the interface. The data taken with this technique show a rate dependence not present in the analytical JKR theory which is normally used to describe the adhesive contact of two elastic bodies, and which arises from the viscoelastic properties of the bulk polymer. The data is intended to inform the development, and validate the predictions of, microstructural models of PBX deformation and failure.
Vargas-Schaffer, Grisell; Nowakowsky, Michal; Eghtesadi, Marzieh; Cogan, Jennifer
2015-09-15
Chronic chest pain is a challenge, and serratus anterior muscle pain syndrome (SAMPS) is often overlooked. We have developed an ultrasound-guided technique for infiltrating local anesthetics and steroids in patients with SAMPS. In 8 patients, the duration of chronic pain was approximately 19 months. Three months after treatment, all patients had experienced a significant reduction in pain. Infiltration for SAMPS confirms the diagnosis and provides adequate pain relief.
Mathematical Intelligence and Mathematical Creativity: A Causal Relationship
ERIC Educational Resources Information Center
Tyagi, Tarun Kumar
2017-01-01
This study investigated the causal relationship between mathematical creativity and mathematical intelligence. Four hundred thirty-nine 8th-grade students, age ranged from 11 to 14 years, were included in the sample of this study by random cluster technique on which mathematical creativity and Hindi adaptation of mathematical intelligence test…
Rizzo, Rosario; Checchi, Vittorio; Marsili, Federico; Zani, Antonio; Incerti-Parenti, Serena; Checchi, Luigi
2017-01-01
Nowadays, there are many techniques to compensate bone atrophies of the posterior maxilla in order to obtain an implant-supported rehabilitation. This case series describes the Ebanist technique: a sinus lift procedure to be used in case of extremely resorbed bone crests (≤3 mm) allowing simultaneous implant placement. With a dedicated cylindrical trephine bur, it is possible to harvest a cylinder of bone from a fresh mineralized frozen homologous bone block graft and to simultaneously create a trapdoor on the recipient site. The trapdoor cortical bone is detached from the sinus membrane and removed. Dental implant is placed into the graft before the grafting procedure since the cylindrical block, once inserted in the recipient area, is not able to oppose sufficient resistance to the torque needed for implant placement. Second-stage surgery and following prosthetic rehabilitation were performed after 5 months. In all cases, implant stability was manually checked and no pathological symptoms or signs were recovered at any follow-up visit. This technique can be considered a valid procedure for implant therapy on atrophic posterior upper maxillae, when the residual bone crest is extremely resorbed.
Campan, M; Le Pape, G; Benziane, T
1994-04-01
Description of the sexual behaviour of Calliphora vomitoria (Diptera: Calliphoridae) with a lexical analysis software package. The sexual behaviour of Calliphora vomitoria was described using a lexical analysis software package considering courtship as a series of words, without any arbitrary categorization. Normal as well as manipulated partners of both sexes were presented to the males. Results showed that normal courtship and copulation occurred when the wings were modified but present and correctly oriented, whereas perturbations were observed and copulation disappeared after inversion and various head modifications. Missing elements (head and wings) were less disruptive than their inversion. If the partner was supposed to be scanned from the head to the abdomen via the wings and if it was supposed to perceive the relative position of these different parts, it is obvious that the absence of an element did not act as an error message and courtship and copulation were preserved. On the other hand, inversion of the same elements seemed to induce wrong or inconsistent informations affecting courtship structure, probably because of sequence disturbance. The courtship preservation in front of every kind of manipulation leads us to question what image of the sexual partner is constructed.
Kleynen, Melanie; Braun, Susy M; Bleijlevens, Michel H; Lexis, Monique A; Rasquin, Sascha M; Halfens, Jos; Wilson, Mark R; Beurskens, Anna J; Masters, Rich S W
2014-01-01
Motor learning is central to domains such as sports and rehabilitation; however, often terminologies are insufficiently uniform to allow effective sharing of experience or translation of knowledge. A study using a Delphi technique was conducted to ascertain level of agreement between experts from different motor learning domains (i.e., therapists, coaches, researchers) with respect to definitions and descriptions of a fundamental conceptual distinction within motor learning, namely implicit and explicit motor learning. A Delphi technique was embedded in multiple rounds of a survey designed to collect and aggregate informed opinions of 49 international respondents with expertise related to motor learning. The survey was administered via an online survey program and accompanied by feedback after each round. Consensus was considered to be reached if ≥70% of the experts agreed on a topic. Consensus was reached with respect to definitions of implicit and explicit motor learning, and seven common primary intervention strategies were identified in the context of implicit and explicit motor learning. Consensus was not reached with respect to whether the strategies promote implicit or explicit forms of learning. The definitions and descriptions agreed upon may aid translation and transfer of knowledge between domains in the field of motor learning. Empirical and clinical research is required to confirm the accuracy of the definitions and to explore the feasibility of the strategies that were identified in research, everyday practice and education.
Kleynen, Melanie; Braun, Susy M.; Bleijlevens, Michel H.; Lexis, Monique A.; Rasquin, Sascha M.; Halfens, Jos; Wilson, Mark R.; Beurskens, Anna J.; Masters, Rich S. W.
2014-01-01
Background Motor learning is central to domains such as sports and rehabilitation; however, often terminologies are insufficiently uniform to allow effective sharing of experience or translation of knowledge. A study using a Delphi technique was conducted to ascertain level of agreement between experts from different motor learning domains (i.e., therapists, coaches, researchers) with respect to definitions and descriptions of a fundamental conceptual distinction within motor learning, namely implicit and explicit motor learning. Methods A Delphi technique was embedded in multiple rounds of a survey designed to collect and aggregate informed opinions of 49 international respondents with expertise related to motor learning. The survey was administered via an online survey program and accompanied by feedback after each round. Consensus was considered to be reached if ≥70% of the experts agreed on a topic. Results Consensus was reached with respect to definitions of implicit and explicit motor learning, and seven common primary intervention strategies were identified in the context of implicit and explicit motor learning. Consensus was not reached with respect to whether the strategies promote implicit or explicit forms of learning. Discussion The definitions and descriptions agreed upon may aid translation and transfer of knowledge between domains in the field of motor learning. Empirical and clinical research is required to confirm the accuracy of the definitions and to explore the feasibility of the strategies that were identified in research, everyday practice and education. PMID:24968228
Salzmann, Stephan N; Lampe, Lukas P; Fernholz, Brian; Härtl, Roger; Patsalides, Athos; Hughes, Alexander P
2017-10-01
Pseudomeningoceles are a rare cause of bone erosions. Development of such erosions in the C2 vertebral body and the odontoid process can lead to life-threatening instability. Treatment options to regain stability include atlantoaxial and occipitocervical fusion. For patients with a history of Chiari decompression and large C2 lesions, common fusion techniques are not always feasible. In addition, fusion surgery sacrifices physiologic motion and is therefore a disabling procedure, especially for young and active patients. We report a novel combined open operative and subsequent minimal invasive filling technique of several instable osteolytic/cystic areas within the C2 vertebra of a 28-year-old woman. The underlying cause for the lesions was a pseudomeningocele communicating with the vertebral body. This was an incidental finding 15 years after foramen magnum decompression with C1 and partial C2 laminectomy for Chiari malformation. Novel treatment included open posterior surgery with total laminectomy of the remaining C2 arch and refilling the odontoid with viscous beta tricalcium phosphate and polymethylmethacrylate bone cement. Postoperative 6- and 12-month follow-up computed tomography imaging showed a stable incorporation of the filling. Life-threatening fractures at the occipitocervical junction are rare and often are due to high-impact trauma. Osteolytic changes at those bone compartments are a potential cause for pathologic fractures during normal daily activities. In this case, increased pressure on the bone due to a pseudomeningocele resulted in slow bone loss without symptoms. A novel combined technique of bone filling was applied successfully to stabilize the C2 vertebral bone. Copyright © 2017 Elsevier Inc. All rights reserved.
Pope, G.A.; Sepehrnoori, K.
1992-12-31
This second annual report on innovative uses of tracers for reservoir characterization contains four sections each describing a novel use of oilfield tracers. The first section describes and illustrates the use of a new single-well tracer test to estimate wettability. This test consists of the injection of brine containing tracers followed by oil containing tracers, a shut-in period to allow some of the tracers to react, and then production of the tracers. The inclusion of the oil injection slug with tracers is unique to this test, and this is what makes the test work. We adapted our chemical simulator, UTCHEM, to enable us to study this tracer method and made an extensive simulation study to evaluate the effects of wettability based upon characteristic curves for relative permeability and capillary pressure for differing wetting states typical of oil reservoirs. The second section of this report describes a new method for analyzing interwell tracer data based upon a type-curve approach. Theoretical frequency response functions were used to build type curves of ``transfer function`` and ``phase spectrum`` that have dimensionless heterogeneity index as a parameter to characterize a stochastic permeability field. We illustrate this method by analyzing field tracer data. The third section of this report describes a new theory for interpreting interwell tracer data in terms of channeling and dispersive behavior for reservoirs. Once again, a stochastic approach to reservoir description is taken. The fourth section of this report describes our simulation of perfluorocarbon gas tracers. This new tracer technology developed at Brookhaven National Laboratory is being tested at the Elk Hills Naval Petroleum Reserve No. 1 in California. We report preliminary simulations made of these tracers in one of the oil reservoirs under evaluation with these tracers in this field. Our compostional simulator (UTCOMP) was used for this simulation study.
NASA Technical Reports Server (NTRS)
Edwards, S. F.; Kantsios, A. G.; Voros, J. P.; Stewart, W. F.
1975-01-01
The development of a radiometric technique for determining the spectral and total normal emittance of materials heated to temperatures of 800, 1100, and 1300 K by direct comparison with National Bureau of Standards (NBS) reference specimens is discussed. Emittances are measured over the spectral range of 1 to 15 microns and are statistically compared with NBS reference specimens. Results are included for NBS reference specimens, Rene 41, alundum, zirconia, AISI type 321 stainless steel, nickel 201, and a space-shuttle reusable surface insulation.
Sampson, Matthew J; Rezaian, Nimah; Hopkins, James M K
2015-04-01
Iliopsoas impingement is a commonly recognised source of groin pain following total hip replacement. When conservative measures fail, open or arthroscopic iliopsoas tendon release can reliably alleviate pain and improve function. This article describes an alternative ultrasound-guided percutaneous technique, achieving iliopsoas tenotomy utilising a modified 18G coaxial needle and thus minimising the morbidity and cost associated with an open or arthroscopic procedure. This method proved successful with resultant complete resolution of patient symptoms. To the knowledge of the authors, this is the first case of ultrasound-guided percutaneous iliopsoas tenotomy for iliopsoas impingement post total hip replacement. © 2015 The Royal Australian and New Zealand College of Radiologists.
NASA Astrophysics Data System (ADS)
Salk, Kateri R.; Erler, Dirk V.; Eyre, Bradley D.; Carlson-Perret, Natasha; Ostrom, Nathaniel E.
2017-08-01
Understanding the magnitude of nitrogen (N) loss and recycling pathways is crucial for coastal N management efforts. However, quantification of denitrification and anammox by a widely-used method, the isotope pairing technique, is challenged when dissimilatory NO3- reduction to NH4+ (DNRA) occurs. In this study, we describe a revised isotope pairing technique that accounts for the influence of DNRA on NO3- reduction (R-IPT-DNRA). The new calculation procedure improves on previous techniques by (1) accounting for N2O production, (2) distinguishing canonical anammox from coupled DNRA-anammox, and (3) including the production of 30N2 by anammox in the quantification of DNRA. This approach avoids the potential for substantial underestimates of anammox rates and overestimates of denitrification rates in systems where DNRA is a significant NO3- reduction pathway. We apply this technique to simultaneously quantify rates of anammox, denitrification, and DNRA in intact sediments adjacent to a seagrass bed in subtropical Australia. The effect of organic carbon lability on NO3- reduction was also addressed by adding detrital sources with differing C:N (phytoplankton- or seagrass-derived). DNRA was the predominant pathway, contributing 49-74% of total NO3- reduction (mean 0.42 μmol N m-2 h-1). In this high C:N system, DNRA outcompetes denitrification for NO3-, functioning to recycle rather than remove N. Anammox exceeded denitrification (mean 0.18 and 0.04 μmol N m-2 h-1, respectively) and accounted for 64-86% of N loss, a rare high percentage in shallow coastal environments. Owing to low denitrification activity, N2O production was ∼100-fold lower than in other coastal sediments (mean 7.7 nmol N m-2 h-1). All NO3- reduction pathways were stimulated by seagrass detritus but not by phytoplankton detritus, suggesting this microbial community is adapted to process organic matter that is typically encountered. The R-IPT-DNRA is widely applicable in other environments where the
Chabot, David Leonard; Polimenakos, Anastasios C.
2011-01-01
Abstract: Since the introduction of the Norwood procedure for surgical palliation of hypoplastic left heart syndrome in 1983, refinements have been made to the original procedure to improve patient outcomes while still accomplishing the original goals of the procedure. One of these refinements has been the introduction of regional selective perfusion to limit the duration of circulatory arrest times and optimize the regional flow distribution. In this paper we describe our technique for performing selective cerebral and lower body perfusion during the Norwood procedure. PMID:22416608
Fatone, Stefania; Caldwell, Ryan
2017-01-01
Background: Current transfemoral prosthetic sockets restrict function, lack comfort, and cause residual limb problems. Lower proximal trim lines are an appealing way to address this problem. Development of a more comfortable and possibly functional subischial socket may contribute to improving quality of life of persons with transfemoral amputation. Objectives: The purpose of this study was to (1) describe the design and fabrication of a new subischial socket and (2) describe efforts to teach this technique. Study design: Development project. Methods: Socket development involved defining the following: subject and liner selection, residual limb evaluation, casting, positive mold rectification, check socket fitting, definitive socket fabrication, and troubleshooting of socket fit. Three hands-on workshops to teach the socket were piloted and attended by 30 certified prosthetists and their patient models. Results: Patient models responded positively to the comfort, range of motion, and stability of the new socket while prosthetists described the technique as “straight forward, reproducible.” Conclusion: To our knowledge, this is the first attempt to create a teachable subischial socket, and while it appears promising, more definitive evaluation is needed. Clinical relevance We developed the Northwestern University Flexible Subischial Vacuum (NU-FlexSIV) Socket as a more comfortable alternative to current transfemoral sockets and demonstrated that it could be taught successfully to prosthetists. PMID:28094686
Aguiar Leonardi, Adriano Barros de; Severino, Nilson Roberto; Junior, Aires Duarte
2015-01-01
To assess the presence of tibial bone tunnel enlargement after surgery to reconstruct the anterior cruciate ligament using quadruple flexor tendon grafts, and to propose a new technique for its measurement. Methods: The study involved 25 patients aged 18-43 years over a six-month period. The assessment was based on radiographs taken immediately postoperatively and in the third and sixth months of evolution after operations to reconstruct the anterior cruciate ligament using grafts from the tendons of the semitendinosus and gracilis muscles, fixed in the femur with a transverse metal screw and in the tibia with an interference screw. The radiographs were evaluated in terms of the relative value between the diameter of the tunnel and the bone, both at 2 cm below the medial tibial condyle. Results: There were significant increases in tunnel diameters: 20.56% for radiographs in anteroposterior view and 26.48% in lateral view. Enlargement was present in 48% of anteroposterior and lateral radiographs, but was present in both views in only 16% of the cases. Conclusions: Bone tunnel enlargement is a phenomenon found in the first months after surgery to reconstruct the anterior cruciate ligament. The measurement technique proposed in this study was sufficient to detect it. PMID:27027030
Favret, Eduardo A; Fuentes, Néstor O; Molina, Ana M; Setten, Lorena M
2008-10-01
During the last few years, RIMAPS technique has been used to characterize the micro-relief of metallic surfaces and recently also applied to biological surfaces. RIMAPS is an image analysis technique which uses the rotation of an image and calculates its average power spectrum. Here, it is presented as a tool for describing the morphology of the trichodium net found in some grasses, which is developed on the epidermal cells of the lemma. Three different species of grasses (herbarium samples) are analyzed: Podagrostis aequivalvis (Trin.) Scribn. & Merr., Bromidium hygrometricum (Nees) Nees & Meyen and Bromidium ramboi (Parodi) Rúgolo. Simple schemes representing the real microstructure of the lemma are proposed and studied. RIMAPS spectra of both the schemes and the real microstructures are compared. These results allow inferring how similar the proposed geometrical schemes are to the real microstructures. Each geometrical pattern could be used as a reference for classifying other species. Finally, this kind of analysis is used to determine the morphology of the trichodium net of Agrostis breviculmis Hitchc. As the dried sample had shrunk and the microstructure was not clear, two kinds of morphology are proposed for the trichodium net of Agrostis L., one elliptical and the other rectilinear, the former being the most suitable.
Tobias-Machado, Marcos; Nunes-Silva, Igor; Hidaka, Alexandre Kiyoshi; Sato, Leticia Lumy Kanawa; Almeida, Roberto; Colombo, Jose Roberto; Zampolli, Hamilton de Campos; Pompeo, Antonio Carlos Lima
2016-01-01
Abstract Introduction: Retzus-sparing robotic-assisted radical prostatectomy(RARP) is a newly approach that preserve the Retzus structures and provide better recovery of continence and erectile function. In Brazil, this approach has not yet been previously reported. Objective: Our goal is to describe Step-by-Step the Retzus-sparing RARP surgical technique and report our first Brazilian experience. Methods: We present a case of a 60-year-old white man with low risk prostate cancer. Surgical materials were four arms Da Vinci robotic platform system, six transperitoneal portals, two prolene wires and Polymer Clips. This surgical technique was step-by-step described according to Galfano et al. One additional step was added as a modification of Galfano et al. Primary technique description: The closure of the Denovellier fascia. Results: We have operated one patient with this technique. The operative time was 180minutes, console time was135 min, the blood loss was 150ml, none perioperative or postoperative complications was found, hospital stay of 01 day. The anatomopathological classification revealed a pT2aN0M0 specimen with free surgical margins. The patient achieved continence immediately after bladder stent retrieval. Full erection reported after 30 days of surgery. Conclusion: Retzus-sparing RARP approach is feasible and reproducible. However, further comparative studies are necessary to demonstrate potential benefits in continence and sexual outcomes over the standard approaches. PMID:27649115
Cheboyina, Sreekhar; O'Haver, John; Wyandt, Christy M
2006-01-01
A mathematical model was developed based on the theory of drop formation to predict the size of the pellets formed in the freeze pelletization process. Further the model was validated by studying the effect of various parameters on the pellet size such as viscosity of the pellet forming and column liquids, surface/interfacial tension, density difference between pellet forming and column liquids; size, shape, and material of construction of the needle tips and temperatures maintained in the columns. In this study, pellets were prepared from different matrices including polyethylene glycols and waxes. The column liquids studied were silicone oils and aqueous glycerol solutions. The surface/interfacial tension, density difference between pellet forming and column liquids and needle tip size were found to be the most important factors affecting pellet size. The viscosity of the column liquid was not found to significantly affect the size of the pellets. The size of the pellets was also not affected by the pellet forming liquids of low viscosities. An increase in the initial column temperature slightly decreased the pellet size. The mathematical model developed was found to successfully predict the size of the pellets with an average error of 3.32% for different matrices that were studied.
Malentacca, Augusto; Lajolo, Carlo
2015-01-01
Diaphanisation and other in vitro endodontic models (i.e., plastic blocks, micro-CT reconstruction, computerised models) do not recreate real root canal working conditions: a more realistic endodontic model is essential for testing endodontic devices and teaching purposes. The aim of this study was to describe a new technique to construct transparent teeth without decalcifying and evaluate the micro-hardness of so treated teeth. Thirty freshly extracted teeth were randomly divided into three groups as follows: 10 non-treated teeth (4 molars, 3 premolars, 3 incisors; control group - G1), 10 teeth were diaphanised (4 molars, 4 premolars, 2 incisors - G2) and 10 teeth were treated with the new proposed technique (2 molars, 6 premolars, 2 incisors - G3). Vickers hardness tester (MHT-4 and AxioVision microscope, Carl Zeiss, 37030 Gottingen, Germany - load=50 g, dwell time=20s, slope=5, 50× magnification) was used to determine microhardness (Vickers Hardness Number - VHN). Statistical analysis was performed using the Intercooled Stata 8.0 software (Stata Corporation, College Station, TX, USA). Only groups 1 and 3 could be tested for hardness because diaphanised teeth were too tender and elastic. Differences in enamel VHN were observed between G1 (mean 304.29; DS=10.44; range 283-321) and G3 (mean 318.51; DS=14.36; range 295.5-339.2) - (p<0.05); differences in dentine VHN were observed between G1 (mean 74.73; DS=6.62; range 63.9-88.1) and G3 (mean 64.54; DS=5.55; range 51.2-72.3) - (p<0.05). G3 teeth presented a slightly lower VHN compared to G1, probably due to some little structural differences among groups, and were dramatically harder than the diaphanised teeth. The described technique, thus, can be considered ideal for testing endodontic instruments and for teaching purposes. Copyright © 2014 Elsevier GmbH. All rights reserved.
Bolek, Matthew G; Szmygiel, Cleo; Kubat, Austin; Schmidt-Rhaesa, Andreas; Hanelt, Ben
2013-01-01
We review recent advances in the use of non-adult gordiid cyst stages to locate gordiids over large geographical regions and new culturing techniques which can help overcome current difficulties in nematomorph biodiversity studies. Using these techniques, we collected a new species of gordiid as cysts in aquatic snails (Biomphalaria pfeifferi) from the Lake Victoria Basin, western Kenya, Africa and cultured them in the laboratory. We describe the adult free-living male and female worms using morphological (light and scanning electron microscopy) and molecular data as well as the life cycle, mating and oviposition behavior, egg strings, eggs, larvae, and cysts of this new species. Chordodes kenyaensis n. sp. belongs to a large group of African Chordodes in which simple areoles are smooth or superficially structured less so than "blackberry" areoles but contain filamentous projections. Present among the simple areoles are clusters of bulging areoles, crowned and circurmcluster areoles along with thorn and tubercle areoles. In the laboratory, worms developed and emerged within 53-78 days from three, species of laboratory-reared crickets exposed to cysts of this species. Adult male and female C. kenyaensis n. sp. initiated typical Gordian knots within hours to days of being placed together and males deposited masses of sperm on the cloacal region of females. Females began oviposition within a week of copulating and attached egg strings in a continuous zigzag pattern on small branches or air-hoses but never free in the water column. Larvae hatched within two to three weeks, and cysts developed in laboratory-reared and exposed snails within 14-24 days. Morphological characteristics of egg strings, eggs, larvae and cysts of C. kenyaensis were most similar to other gordiids in the genus Chordodes but differed morphologically from other gordiid genera for which similar information is available.
NASA Astrophysics Data System (ADS)
Radicioni, F.; Matracchi, P.; Brigante, R.; Brozzi, A.; Cecconi, M.; Stoppini, A.; Tosi, G.
2017-05-01
The Tempio della Consolazione in Todi (16th cent.) has always been one of the most significant symbols of the Umbrian landscape. Since the first times after its completion (1606) the structure has exhibited evidences of instability, due to foundation subsiding and/or seismic activity. Structural and geotechnical countermeasures have been undertaken on the Tempio and its surroundings from the 17th century until recent times. Until now a truly satisfactory analysis of the overall deformation and attitude of the building has not been performed, since the existing surveys record the overhangs of the pillars, the crack pattern or the subsidence over limited time spans. Describing the attitude of the whole church is in fact a complex operation due to the architectural character of the building, consisting of four apses (three polygonal and one semicircular) covered with half domes, which surround the central area with the large dome. The present research aims to fill the gap of knowledge with a global study based on geomatic techniques for an accurate 3D reconstruction of geometry and attitude, integrated with a historical research on damage and interventions and a geotechnical analysis. The geomatic survey results from the integration of different techniques: GPS-GNSS for global georeferencing, laser scanning and digital photogrammetry for an accurate 3D reconstruction, high precision total station and geometric leveling for a direct survey of deformations and cracks, and for the alignment of the laser scans. The above analysis allowed to assess the dynamics of the cracks occurred in the last 25 years by a comparison with a previous survey. From the photographic colour associated to the point cloud was also possible to map the damp patches showing on the domes intrados, mapping their evolution over the last years.
NASA Technical Reports Server (NTRS)
Zolotukhin, V. G.; Kolosov, B. I.; Usikov, D. A.; Borisenko, V. I.; Mosin, S. T.; Gorokhov, V. N.
1980-01-01
A description of a batch of programs for the YeS-1040 computer combined into an automated system for processing photo (and video) images of the Earth's surface, taken from spacecraft, is presented. Individual programs with the detailed discussion of the algorithmic and programmatic facilities needed by the user are presented. The basic principles for assembling the system, and the control programs are included. The exchange format within whose framework the cataloging of any programs recommended for the system of processing will be activated in the future is displayed.
NASA Astrophysics Data System (ADS)
Fraga, Ignacio; Cea, Luis; Puertas, Jerónimo; Salsón, Santiago; Petazzi, Alberto
2016-04-01
In this paper we present a new methodology to compute rainfall fields including the quantification of predictions uncertainties using raingauge network data. The proposed methodology comprises two steps. Firstly, the ordinary krigging technique is used to determine the estimated rainfall depth in every point of the study area. Then multiple equi-probable errors fields, which comprise both interpolation and measuring uncertainties, are added to the krigged field resulting in multiple rainfall predictions. To compute these error fields first the standard deviation of the krigging estimation is determined following the cross-validation based procedure described in Delrieu et al. (2014). Then, the standard deviation field is sampled using non-conditioned Gaussian random fields. The proposed methodology was applied to study 7 rain events in a 60x60 km area of the west coast of Galicia, in the Northwest of Spain. Due to its location at the junction between tropical and polar regions, the study area suffers from frequent intense rainfalls characterized by a great variability in terms of both space and time. Rainfall data from the tipping bucket raingauge network operated by MeteoGalicia were used to estimate the rainfall fields using the proposed methodology. The obtained predictions were then validated using rainfall data from 3 additional rain gauges installed within the CAPRI project (Probabilistic flood prediction with high resolution hydrologic models from radar rainfall estimates, funded by the Spanish Ministry of Economy and Competitiveness. Reference CGL2013-46245-R.). Results show that both the mean hyetographs and the peak intensities are correctly predicted. The computed hyetographs present a good fit to the experimental data and most of the measured values fall within the 95% confidence intervals. Also, most of the experimental values outside the confidence bounds correspond to time periods of low rainfall depths, where the inaccuracy of the measuring devices
The Emergence of Objects from Mathematical Practices
ERIC Educational Resources Information Center
Font, Vicenc; Godino, Juan D.; Gallardo, Jesus
2013-01-01
The nature of mathematical objects, their various types, the way in which they are formed, and how they participate in mathematical activity are all questions of interest for philosophy and mathematics education. Teaching in schools is usually based, implicitly or explicitly, on a descriptive/realist view of mathematics, an approach which is not…
The Emergence of Objects from Mathematical Practices
ERIC Educational Resources Information Center
Font, Vicenc; Godino, Juan D.; Gallardo, Jesus
2013-01-01
The nature of mathematical objects, their various types, the way in which they are formed, and how they participate in mathematical activity are all questions of interest for philosophy and mathematics education. Teaching in schools is usually based, implicitly or explicitly, on a descriptive/realist view of mathematics, an approach which is not…
Mashaly, Hazem; Paschel, Erin E; Khattar, Nicolas K; Goldschmidt, Ezequiel; Gerszten, Peter C
2016-01-01
OBJECTIVE The development of symptomatic adjacent-segment disease (ASD) is a well-recognized consequence of lumbar fusion surgery. Extension of a fusion to a diseased segment may only lead to subsequent adjacent-segment degeneration. The authors report the use of a novel technique that uses dynamic stabilization instead of arthrodesis for the surgical treatment of symptomatic ASD following a prior lumbar instrumented fusion. METHODS A cohort of 28 consecutive patients was evaluated who developed symptomatic stenosis immediately adjacent to a previous lumbar instrumented fusion. All patients had symptoms of neurogenic claudication refractory to nonsurgical treatment and were surgically treated with decompression and dynamic stabilization instead of extending the fusion construct using a posterior lumbar dynamic stabilization system. Preoperative symptoms, visual analog scale (VAS) pain scores, and perioperative complications were recorded. Clinical outcome was gauged by comparing VAS scores prior to surgery and at the time of last follow-up. RESULTS The mean follow-up duration was 52 months (range 17-94 months). The mean interval from the time of primary fusion surgery to the dynamic stabilization surgery was 40 months (range 10-96 months). The mean patient age was 51 years (range 29-76 years). There were 19 (68%) men and 9 (32%) women. Twenty-three patients (82%) presented with low-back pain at time of surgery, whereas 24 patients (86%) presented with lower-extremity symptoms only. Twenty-four patients (86%) underwent operations that were performed using single-level dynamic stabilization, 3 patients (11%) were treated at 2 levels, and 1 patient underwent 3-level decompression and dynamic stabilization. The most commonly affected and treated level (46%) was L3-4. The mean preoperative VAS pain score was 8, whereas the mean postoperative score was 3. No patient required surgery for symptomatic degeneration rostral to the level of dynamic stabilization during the
Ryan, Nicola; Gonzalo, Nieves; Dingli, Philip; Cruz, Oscar Vedia; Jiménez-Quevedo, Pilar; Nombela-Franco, Luis; Nuñez-Gil, Ivan; Trigo, María Del; Salinas, Pablo; Macaya, Carlos; Fernandez-Ortiz, Antonio; Escaned, Javier
2017-02-14
Inability to cross the lesion with a guidewire is the most common reason for failure in percutaneous revascularization (PCI) of chronic total occlusions (CTOs). An ostial or stumpless CTO is an acknowledged challenge for CTO recanalization due to difficulty in successful wiring. IVUS imaging provides the opportunity to visualize the occluded vessel and to aid guidewire advancement. We review the value of this technique in a single-centre experience of CTO PCI. This series involves 22 patients who underwent CTO-PCI using IVUS guidance for stumpless CTO wiring at our institution. CTO operators with extensive IVUS experience in non-CTO cases carried out all procedures. Procedural and outcome data was prospectively entered into the institutional database and a retrospective analysis of clinical, angiographic and technical data performed. 17 (77%) of the 22 procedures were successful. The mean age was 59.8 ± 11.5 years, and 90.9% were male. The most commonly attempted lesions were located in the left anterior descending 36.4% (Soon et al. in J Intervent Cardiol 20(5):359-366, 2007) and Circumflex artery (LCx) 31.8% (Mollet et al. in Am J Cardiol 95(2):240-243, 2005). Mean JCTO score was 3.09 ± 0.75 (3.06 ± 0.68, 3.17 ± 0.98 in the successful and failed groups respectively p = 0.35). The mean contrast volume was 378.7 ml ± 114.7 (389.9 ml ± 130.5, 349.2 ml ± 52.2 p = 0.3 in the successful and failed groups respectively). There was no death, coronary artery bypass grafting or myocardial infarction requiring intervention in this series. When the success rates were analyzed taking into account the date of adoption of this technique, the learning curve had no significant impact on CTO-PCI success. This series describes a good success rate in IVUS guided stumpless wiring of CTOs in consecutive patients with this complex anatomical scenario.
Cardinale, Francesco; Pero, Guglielmo; Quilici, Luca; Piano, Mariangela; Colombo, Paola; Moscato, Alessio; Castana, Laura; Casaceli, Giuseppe; Fuschillo, Dalila; Gennari, Luciana; Cenzato, Marco; Lo Russo, Giorgio; Cossu, Massimo
2015-08-01
Cerebrovascular imaging is critical for safe and accurate planning of Stereo-ElectroEncephaloGraphy (SEEG) electrode trajectory. We developed a new technique for Cone Beam Computed Tomography (CBCT) Three-Dimensional Digital Subtraction Angiography (3D DSA). The workflow core is the acquisition of computed tomography datasets without (bone mask) and with selective injection of contrast medium in the main brain-feeding arteries, followed by dataset registration and subtraction. The images were acquired with the O-armTM 1000 System (Medtronic). Images were postprocessed with FSL software package. We retrospectively analyzed 191 3D DSA procedures and qualitatively analyzed the quality of each 3D DSA dataset. The quality of 3D DSA was good in 150 procedures, sufficient in 37, and poor in 4. 3D rendering of the vascular tree was helpful for both SEEG implantation and resective surgery planning. Angiography complications occurred in only one procedure that was aborted due to a major allergic reaction to contrast medium. No other complications directly related to 3D DSA occurred. Minor intracerebral hemorrhage occurred in 2/191 patients after SEEG implantation, with no permanent sequelae. CBCT 3D DSA is a safe diagnostic procedure for SEEG electrode trajectory planning and for 3D reconstructions of the vascular tree in multimodal scenes for resections. The high fidelity and geometric accuracy contribute to the safety of electrode implantation. Copyright © 2015 Elsevier Inc. All rights reserved.
Newell, K.D.
2007-01-01
Drill cuttings can be used for desorption analyses but with more uncertainty than desorption analyses done with cores. Drill cuttings are not recommended to take the place of core, but in some circumstances, desorption work with cuttings can provide a timely and economic supplement to that of cores. The mixed lithologic nature of drill cuttings is primarily the source of uncertainty in their analysis for gas content, for it is unclear how to apportion the gas generated from both the coal and the dark-colored shale that is mixed in usually with the coal. In the Western Interior Basin Coal Basin in eastern Kansas (Pennsylvanian-age coals), dark-colored shales with normal (??? 100 API units) gamma-ray levels seem to give off minimal amounts of gas on the order of less than five standard cubic feet per ton (scf/ton). In some cuttings analyses this rule of thumb for gas content of the shale is adequate for inferring the gas content of coals, but shales with high-gamma-ray values (>150 API units) may yield several times this amount of gas. The uncertainty in desorption analysis of drill cuttings can be depicted graphically on a diagram identified as a "lithologic component sensitivity analysis diagram." Comparison of cuttings desorption results from nearby wells on this diagram, can sometimes yield an unique solution for the gas content of both a dark shale and coal mixed in a cuttings sample. A mathematical solution, based on equating the dry, ash-free gas-contents of the admixed coal and dark-colored shale, also yields results that are correlative to data from nearby cores. ?? 2007 International Association for Mathematical Geology.
Mathematical studies of parasitic infection and immunity.
Anderson, R M
1994-06-24
The techniques that underpin modern molecular biology have been rapidly adopted by those interested in the major parasitic infections of humans. The parasitological literature is full of reports of genes and their amino acid sequences, of molecules, of cell membrane receptors and channels, and of the fine details of the immunological responses mounted by the host to combat infection. Much less enthusiasm has been shown for the mathematical techniques that facilitate the analysis and interpretation of dynamical processes such as transmission, evolution, and the interplay between parasite population growth and immunological responses within the host. Molecular techniques provide enormous opportunities for description, but ultimately, understanding biological systems with the precision that physicists and engineers aspire to in their own fields will require quantitative description of the many rate processes that dictate both an observed pattern and the dynamics of its change.
Asimakopoulos, Anastasios D; Corona Montes, Victor Enrique; Gaston, Richard
2012-12-01
The preservation of sexual potency after radical prostatectomy has always been the topic of much anxiety and debate. While cancer control and urinary continence are of supreme importance, the preservation of sexual function completes the trifecta that both patient and surgeon strive to achieve. The introduction of robotic assistance to modern laparoscopic surgery has provided many advantages, the two greatest being improved three-dimensional magnified vision and wristed instrumentation. These technical enhancements provide the surgeon with improved surgical tools that have the potential to facilitate a more precise surgical approach. One of the potential advantages during robot-assisted laparoscopic prostatectomy (RALP) is improving visualization, control, and dissection of the neurovascular bundle (NVB). With this article, we provide the description of our current technique of intrafascial, tension and energy-free dissection of the NVB during RALP, aiming to maximize the preservation of the periprostatic neuronal network and improve erectile function outcomes. A step-by-step description of the preservation of the pubovesical complex is also provided.
Demirkiran, Gokhan; Theologis, Alexander A; Pekmezci, Murat; Ames, Christopher; Deviren, Vedat
2016-05-01
Case series. To evaluate radiographic and clinical outcomes of adults with spinal deformity treated with multilevel anterior column releases (ACR). Pedicle subtraction osteotomy can be used effectively to correct spinal deformity; however, it is not without complications. ACR is an attractive alternative minimally invasive technique for spinal deformity correction, although few clinical reports on its clinical effectiveness exist. Adults with spinal deformity who underwent multilevel ACRs (≥2) followed by open posterior instrumentation with a minimum 1-year follow-up were retrospectively reviewed. Deformity radiographic data and clinical outcomes, including the Oswestry Disability Index (ODI) and the EuroQol-5D were analyzed. Eight patients [7 female, 1 male; mean age 65 y (49-79 y)] met inclusion criteria. The mean follow-up was 18.4 months (12-28 mo). The average number of levels treated with an ACR per patient was 2.4 (2-3). There were no anterior approach-related complications. The average number of levels instrumented posteriorly was 8.1 (3-15). Six patients underwent Schwab type 1 posterior osteotomies (partial facetectomies). After the first anterior stage, there was a significant increase in the lumbar lordosis and significant decreases in the sagittal vertical axis, pelvic tilt, and lumbopelvic mismatch (P<0.05). After the second stage there was no significant change in the sagittal vertical axis, lumbar lordosis, pelvic tilt, or lumbopelvic mismatch relative to the values obtained after ACR. There was significantly less disability postoperatively [ODI: 15 (0-30)] compared with preoperatively [ODI: 46 (16-80)] (P<0.01). There was significant improvement in general health after operation, as assessed by the EuroQol-5D utility scores [preop: 0.44 (0.21-0.82) vs. postop: 0.71 (0.60-0.80)] (P=0.01). Back and leg visual analog scale pain scores improved significantly postoperatively. A staged approach using multilevel ACRs with open posterior instrumentation
Gray, W.G.; Tompson, A.; Soll, W.E.
1998-06-01
'Improved capabilities for modeling multiphase flow in the subsurface requires that several aspects of the system which impact the flow and transport processes be more properly accounted for. A distinguishing feature of multiphase flow in comparison to single phase flow is the existence of interfaces between fluids. At the microscopic (pore) scale, these interfaces are known to influence system behavior by supporting non-zero stresses such that the pressures in adjacent phases are not equal. In problems of interphase transport at the macroscopic (core) scale, knowledge of the total amount of interfacial area in the system provides a clue to the effectiveness of the communication between phases. Although interfacial processes are central to multiphase flow physics, their treatment in traditional porous-media theories has been implicit rather than explicit; and no attempts have been made to systematically account for the evolution of the interfacial area in dynamic systems or to include the dependence of constitutive functions, such as capillary pressure, on the interfacial area. This project implements a three-pronged approach to assessing the importance of various features of multiphase flow to its description. The research contributes to the improved understanding and precise physical description of multiphase subsurface flow by combining: (1) theoretical derivation of equations, (2) lattice Boltzmann modeling of hydrodynamics to identify characteristics and parameters, and (3) solution of the field-scale equations using a discrete numerical method to assess the advantages and disadvantages of the complete theory. This approach includes both fundamental scientific inquiry and a path for inclusion of the scientific results obtained in a technical tool that will improve assessment capabilities for multiphase flow situations that have arisen due to the introduction of organic materials in the natural environment. This report summarizes work after 1.5 years of a 3
Wilson, David M; Goh, Clara S S; Palmer, Ross H
2014-08-01
(1) Describe arthroscopic BURP surgical technique, (2) assess association of visual control and surgeon experience to tenotomy completeness and regional iatrogenic tissue damage. Cadaveric study. Canine cadavers weighing >20 kg (n = 16; 32 elbows). Phase 1 = dissection/anatomic description/procedural refinement (n = 6). Phase 2 = technique description (n = 6). Phase 3 = association of surgeon experience and procedural visual control to tenotomy completion and regional iatrogenic damage (n = 20). Elbows were randomly assigned via coin toss to an experienced- or inexperienced-arthroscopist. Using conventional medial portals, surgeons sought to identify the medial collateral ligament (MCL) and ulnar insertion of the biceps tendon (uBT) before attempting complete tenotomy. Upon procedural completion, surgeons assigned a standardized "visual control score" (VCS) describing viewing that governed procedure and predicted % uBT release, MCL, and median nerve damage. Post-procedural dissection determined actual tenotomy completion and iatrogenic tissue damage. Complete BURP was achieved in 16 of 19 elbows. VCS was associated with tenotomy completeness (P < .01). "Blind" BURP was incomplete in both elbows in which it was attempted. Perception of complete BURP was associated with complete release (P < .01). MCL damage occurred in 10% of elbows. Surgeon experience did not influence VCS, regional damage, or BURP completeness. In canine cadavers, arthroscopic BURP can be consistently performed using conventional arthroscopic instruments and portals by both experienced and inexperienced arthroscopists when visual control guides the tenotomy into the distal aspect of the tendon. © Copyright 2014 by The American College of Veterinary Surgeons.
ERIC Educational Resources Information Center
Alter, Krystyn P.; Molloy, John L.; Niemeyer, Emily D.
2005-01-01
A laboratory experiment reinforces the concept of acid-base equilibria while introducing a common application of spectrophotometry and can easily be completed within a standard four-hour laboratory period. It provides students with an opportunity to use advanced data analysis techniques like data smoothing and spectral deconvolution to…
ERIC Educational Resources Information Center
Vazquez, Lorna Thomas
2008-01-01
This article describes the A, E, I, O, U technique, designed to help teachers ensure that teaching and learning are not mutually exclusive in the classroom. Most teachers would agree that motivating average teenagers to communicate how they got an answer or justify their problem-solving strategies can be as difficult as teaching a dog to whistle.…
ERIC Educational Resources Information Center
Vazquez, Lorna Thomas
2008-01-01
This article describes the A, E, I, O, U technique, designed to help teachers ensure that teaching and learning are not mutually exclusive in the classroom. Most teachers would agree that motivating average teenagers to communicate how they got an answer or justify their problem-solving strategies can be as difficult as teaching a dog to whistle.…
ERIC Educational Resources Information Center
Alter, Krystyn P.; Molloy, John L.; Niemeyer, Emily D.
2005-01-01
A laboratory experiment reinforces the concept of acid-base equilibria while introducing a common application of spectrophotometry and can easily be completed within a standard four-hour laboratory period. It provides students with an opportunity to use advanced data analysis techniques like data smoothing and spectral deconvolution to…
Computation and graphics in mathematical research
Hoffman, D.A.; Spruck, J.
1992-08-13
This report discusses: The description of the GANG Project and results for prior research; the center for geometry, analysis, numerics and graphics; description of GANG Laboratory; software development at GANG; and mathematical and scientific research activities.
ERIC Educational Resources Information Center
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…
ERIC Educational Resources Information Center
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…
Experimenting with Mathematical Biology
ERIC Educational Resources Information Center
Sanft, Rebecca; Walter, Anne
2016-01-01
St. Olaf College recently added a Mathematical Biology concentration to its curriculum. The core course, Mathematics of Biology, was redesigned to include a wet laboratory. The lab classes required students to collect data and implement the essential modeling techniques of formulation, implementation, validation, and analysis. The four labs…
Experimenting with Mathematical Biology
ERIC Educational Resources Information Center
Sanft, Rebecca; Walter, Anne
2016-01-01
St. Olaf College recently added a Mathematical Biology concentration to its curriculum. The core course, Mathematics of Biology, was redesigned to include a wet laboratory. The lab classes required students to collect data and implement the essential modeling techniques of formulation, implementation, validation, and analysis. The four labs…
Mathematical epidemiology is not an oxymoron
2009-01-01
A brief description of the importance of communicable diseases in history and the development of mathematical modelling of disease transmission is given. This includes reasons for mathematical modelling, the history of mathematical modelling from the foundations laid in the late nineteenth century to the present, some of the accomplishments of mathematical modelling, and some challenges for the future. Our purpose is to demonstrate the importance of mathematical modelling for the understanding and management of infectious disease transmission. PMID:19922686
NASA Astrophysics Data System (ADS)
Crisan, Emil Gabriel
Certification requirements, optimization and minimum project costs, design of flight control laws and the implementation of flight simulators are among the principal applications of system identification in the aeronautical industry. This document examines the practical application of parameter estimation techniques to the problem of estimating helicopter stability and control derivatives from flight test data provided by Bell Helicopter Textron Canada. The purpose of this work is twofold: a time-domain application of the Output Error method using the Gauss-Newton algorithm and a frequency-domain identification method to obtain the aerodynamic and control derivatives of a helicopter. The adopted model for this study is a fully coupled, 6 degree of freedom (DoF) state space model. The technique used for rotorcraft identification in time-domain was the Maximum Likelihood Estimation method, embodied in a modified version of NASA's Maximum Likelihood Estimator program (MMLE3) obtained from the National Research Council (NRC). The frequency-domain system identification procedure is incorporated in a comprehensive package of user-oriented programs referred to as CIFERRTM. The coupled, 6 DoF model does not include the high frequency main rotor modes (flapping, lead-lag, twisting), yet it is capable of modeling rotorcraft dynamics fairly accurately as resulted from the model verification. The identification results demonstrate that MMLE3 is a powerful and effective tool for extracting reliable helicopter models from flight test data. The results obtained in frequency-domain approach demonstrated that CIFERRTM could achieve good results even on limited data.
NASA Astrophysics Data System (ADS)
Michele, Mangiameli; Giuseppe, Mussumeci; Salvatore, Zito
2017-07-01
The Structure From Motion (SFM) is a technique applied to a series of photographs of an object that returns a 3D reconstruction made up by points in the space (point clouds). This research aims at comparing the results of the SFM approach with the results of a 3D laser scanning in terms of density and accuracy of the model. The experience was conducted by detecting several architectural elements (walls and portals of historical buildings) both with a 3D laser scanner of the latest generation and an amateur photographic camera. The point clouds acquired by laser scanner and those acquired by the photo camera have been systematically compared. In particular we present the experience carried out on the "Don Diego Pappalardo Palace" site in Pedara (Catania, Sicily).
Mathematics Teachers' Criteria of Dimension
ERIC Educational Resources Information Center
Ural, Alattin
2014-01-01
The aim of the study is to determine mathematics teachers' decisions about dimensions of the geometric figures, criteria of dimension and consistency of decision-criteria. The research is a qualitative research and the model applied in the study is descriptive method on the basis of general scanning model. 15 mathematics teachers attended the…
The Mathematics of Global Change
ERIC Educational Resources Information Center
Kreith, Kurt
2011-01-01
This paper is a descriptive and preliminary report on recent efforts to address two questions: 1) Can school mathematics be used to enhance our students' ability to understand their changing world? and 2) What role might computer technology play in this regard? After recounting some of the mathematical tools that led to a better understanding of…
Mathematics Teachers' Criteria of Dimension
ERIC Educational Resources Information Center
Ural, Alattin
2014-01-01
The aim of the study is to determine mathematics teachers' decisions about dimensions of the geometric figures, criteria of dimension and consistency of decision-criteria. The research is a qualitative research and the model applied in the study is descriptive method on the basis of general scanning model. 15 mathematics teachers attended the…
Internet Connections to Mathematics Education.
ERIC Educational Resources Information Center
Day, Roger
1995-01-01
Presents Internet connections appropriate for mathematics education; provides descriptions of ways that mathematics educators can access electronic resources such as e-mail, discussion groups, gopher servers, and transfer of files; and provides hints and examples from classroom connections and professional applications. (18 references) (Author/MKR)
The Mathematics of Global Change
ERIC Educational Resources Information Center
Kreith, Kurt
2011-01-01
This paper is a descriptive and preliminary report on recent efforts to address two questions: 1) Can school mathematics be used to enhance our students' ability to understand their changing world? and 2) What role might computer technology play in this regard? After recounting some of the mathematical tools that led to a better understanding of…
2009-05-27
models for the description of language . I.R.E. Transactions on Information Theory . JT-2, 113-124. [6] Eliashberg, V. 1967. On a class of learning...Molecule to Metaphor. A Neural Theory of Language . A Bradford Book, the MIT Press. [16] Gold, E.M. (1967). Language identification in the limit...the DARPA DSO Mathematical Challenge One: Develop a mathematical theory to build a functional model of the brain that is mathematically consistent and
NASA Technical Reports Server (NTRS)
Johannsen, G.; Rouse, W. B.
1978-01-01
A hierarchy of human activities is derived by analyzing automobile driving in general terms. A structural description leads to a block diagram and a time-sharing computer analogy. The range of applicability of existing mathematical models is considered with respect to the hierarchy of human activities in actual complex tasks. Other mathematical tools so far not often applied to man machine systems are also discussed. The mathematical descriptions at least briefly considered here include utility, estimation, control, queueing, and fuzzy set theory as well as artificial intelligence techniques. Some thoughts are given as to how these methods might be integrated and how further work might be pursued.
ERIC Educational Resources Information Center
Redlich, Otto
1972-01-01
The foundation of science, and of thermodynamics in particular, can be developed cogently and without arbitrariness. The goal of science, description of nature, is externally given; it requires a set of basic concepts as indispensable tools. Mathematics has no similar externally given goal. (Author/TS)
Fostering Creativity Through Mathematics.
ERIC Educational Resources Information Center
Lichtenberg, Betty K., Ed.; Troutman, Andria P., Ed.
The 26 activities described in this volume deal with a wide variety of mathematical ideas. Most of the activities are appropriate for grades 6-9; many could be used with older or younger groups as well. All activities are described in detail; some descriptions include sample worksheets, and several provide suggestions for followup activities. The…
Fostering Creativity Through Mathematics.
ERIC Educational Resources Information Center
Lichtenberg, Betty K., Ed.; Troutman, Andria P., Ed.
The 26 activities described in this volume deal with a wide variety of mathematical ideas. Most of the activities are appropriate for grades 6-9; many could be used with older or younger groups as well. All activities are described in detail; some descriptions include sample worksheets, and several provide suggestions for followup activities. The…
Assessment Mathematics Teacher's Competencies
ERIC Educational Resources Information Center
Alnoor, A. G.; Yuanxiang, Guo; Abudhuim, F. S.
2007-01-01
This paper aimed to identifying the professional efficiencies for the intermediate schools mathematics teachers and tries to know at what level the math teachers experience those competencies. The researcher used a descriptive research approach, the study data collected from specialist educators and teacher's experts and previous studies to…
Experimental Mathematics and Computational Statistics
Bailey, David H.; Borwein, Jonathan M.
2009-04-30
The field of statistics has long been noted for techniques to detect patterns and regularities in numerical data. In this article we explore connections between statistics and the emerging field of 'experimental mathematics'. These includes both applications of experimental mathematics in statistics, as well as statistical methods applied to computational mathematics.
NASA Astrophysics Data System (ADS)
Ong, Jenn Bing; Cohen, Jason
2013-04-01
Presently, the complexity of the properties of and the changes in the vegetation-land surface in Southeast Asia is not well understood. This lack of understanding inhibits its being modeled sufficiently well so as to be useful for climate-scale studies. A few major reasons for this include: (a) the radiative and hydrological properties of the vegetation-land surface is complex, changing both in time and space in response to the phase on the Monsoon; (b) human disturbance and land use change are widespread and increasing in this region, and involve both clearance and fires; and (c) that there are not sufficient measurements currently available to empirically quantify many of the properties of interest. To better quantify the properties of the land surface at large spatial scales and over a decadal time scale, new quantitative methods of analysis are required, and the purpose of this presentation is to show both the proof-of-concept of one such approach, as well as some initial and interesting results. In this study, Principal Component Analysis (PCA) was applied to the roughly 13 year dataset provided by the Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), and Leaf Area Index (LAI). PCA is a tool allowing the extraction of the standing modes of a dataset, reducing a complex dataset to small and orthogonal sets that contribute the most variance to the data. Combining this tool with variance and correlation maps between the measured time series and those derived from the PCA, the spatiotemporal structure of the dataset can be elucidated. This technique allows for different patterns in both space and time over Southeast Asia to be revealed. Comparison using the variance and correlation maps between the time series and the seasonal variations derived from PCA suggest that both the variance and correlation are stronger over Northern Southeast Asia than in Equatorial Southeast Asia. One
Lanza, Fernanda C; Alves, Cintia Santos; dos Santos, Roberta Loures; de Camargo, Anderson Alves; Dal Corso, Simone
2015-03-01
There has not been a detailed description of expiratory reserve volume (ERV) during slow expiration with glottis open in infralateral decubitus position (ELTGOL, for Expiration Lente Totale Glotte Ouverte en infraLatéral) and its reproducibility. The aim of this study was to determine ERV during ELTGOL and to evaluate ERV intra-observer and inter-observer reliability. In this prospective study, subjects were 30-70 y of age with chronic lung disease. ELTGOL (an active-passive or active physiotherapy technique) was applied in random order by 3 observers: 2 trained physiotherapists (PT 1 and PT 2) and the subject him/herself. Two ELTGOL compressions (A and B) were applied by PT 1, PT 2, and the subject. Thirty-two subjects were evaluated with moderate lung obstruction, FEV1: 47.7 ± 15.4, and ERV: 61.7 ± 29.4. The mean value of ERV for PT 1 was 51.4 ± 24.8%; for PT 2, it was 54.3 ± 31.8%; and for the subject, it was 53.5 ± 26.2% (P = .49). Considering the mean value of ERV, the ELTGOL mobilized more than 80% of ERV. There was good reliability intra-PT: PT 1, intraclass correlation coefficient (ICC) 0.85 (0.70-0.93), P < .0001; PT 2, ICC 0.90 (0.80-0.95), P < .0001, and inter-PT (ICC 0.86 [95% CI 0.71-0.93], P < .001). The Bland-Altman plot with mean bias and limits of agreement for ERV of PT 1 and PT 2 was -3.3 (-42.7 to 35.9). ELTGOL mobilized more than 80% of ERV in subjects with moderate airway obstruction; there is no difference in ERV exhaled during the technique applied by a physiotherapist or by the subject. ELTGOL is a reproducible technique, determined by inter- and intra-observer testing. Copyright © 2015 by Daedalus Enterprises.
ERIC Educational Resources Information Center
Reys, Robert; Reys, Rustin
2011-01-01
In their dual roles as mathematics teachers and tennis coaches, the authors have worked with tennis players who have never thought about how a knowledge of mathematics might help them become "better" tennis players. They have also worked with many mathematics students who have never considered how much mathematics is associated with tennis. This…
ERIC Educational Resources Information Center
Reys, Robert; Reys, Rustin
2011-01-01
In their dual roles as mathematics teachers and tennis coaches, the authors have worked with tennis players who have never thought about how a knowledge of mathematics might help them become "better" tennis players. They have also worked with many mathematics students who have never considered how much mathematics is associated with tennis. This…
Gutarra-Vilchez, Rosa B; Pardo-Hernandez, Hector; Arévalo-Rodríguez, Ingrid; Buitrago, Diana; Bonfill, Xavier
2016-08-01
To identify and describe controlled clinical trials (CCTs) published in Spanish Gynaecology and Obstetrics journals. In addition, to assess the quality of the CCTs on Assisted Reproduction Techniques (ART) identified in this project. In order to identify eligible CCTs, all Spanish Gynaecology and Obstetrics journals were handsearched. Handsearching was conducted following the guidelines provided by the Cochrane Collaboration, which state that each journal article must be carefully reviewed, including original articles and other types of studies, letters to the editor, abstracts, and conference presentations. The results of the handsearching process were compared with an electronic search conducted in MEDLINE (PubMed). A descriptive analysis of the main characteristics of the identified CCTs was performed, as well as a methodological assessment of CCTs on ART. Sixteen Gynaecology and Obstetrics journals were identified, four of which have been indexed in MEDLINE at some point, although not currently. The journal with the most CCTs was "Progresos de Obstetricia y Ginecología". A total of 235 CCTs were published in these journals, of which 29 were on ART. Most CCTs (216, 91.9%) were carried out in a hospital setting; 201 (89.4%) were unicentric. Obstetrics was the most studied subspecialty (46.4%). Among CCTs on ART, the risk of bias was predominantly high. The number of CCTs published in Spanish Gynaecology and Obstetrics journals is limited. CCTs on ART present deficiencies in the report of results and low methodological quality. It is advised that authors and journals adhere to the CONSORT statement and to the Cochrane Collaboration recommendations to reduce risk of bias when designing and disseminating research projects. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
CARE 3 phase 2 report - mathematical description
NASA Technical Reports Server (NTRS)
Stiffler, J. J.; Bryant, L. A.
1982-01-01
CARE III (Computer-Aided Reliability Estimation, version three) a computer program designed to help estimate the reliability of complex, redundant systems is described. Although the program can model a wide variety of redundant structures, it was developed specifically for fault tolerant avionics systems. CARE III generalizes the class of system structures that can be modeled and greatly expands the coverage model to take into account such effects as intermittent and transient faults, latent faults, and error propagation.
NAVPAC SST Data Processing--Mathematical Description.
1981-07-01
of the count just in case the count is not completed.) The Doppler count register now contains one less than the total number of Doppler counts...is found in which case the original recovered I1) is printed and L the TMTM is deleted from any further processing. The total number of bad Ii)s is...about each NAVPAC pass are computed and entered in a pass summary table, A subset of these quantities are also totalled over all passes. Elevation and
Le Pape, G; Chevalet, P
1992-01-01
This study illustrates the use of an original technique to give a precise description of the developmental environment provided by female mice to their pups, and of his changes with the age of the pups. Successive events recorded by continous observation of maternal behaviour of C57BL/6 inbred mice were analysed by a technique devoted to textual analysis. The different mothers were easily characterised by differences in the frequencies of the behavioural items expressed on the nest. These individual differences were stable with increasing age of the pups. On the other hand, the frequencies of behavioural sequences showed differences related to the age of the pups. The psychological meaning of some behavioural items is suggested by the results. The relevance of multivariate techniques of description directly applied on initial data of continous observation is discussed. Copyright © 1992 Elsevier Science Publishers B.V. All rights reserved. Published by Elsevier B.V. All rights reserved.
Can Mathematics Education and History of Mathematics Coexist?
NASA Astrophysics Data System (ADS)
Fried, Michael N.
Despite the wide interest in combining mathematics education and the history of mathematics, there are grave and fundamental problems in this effort. The main difficulty is that while one wants to see historical topics in the classroom or an historical approach in teaching, the commitment to teach the modern mathematics and modern mathematical techniques necessary in the pure and applied sciences forces one either to trivialize history or to distort it. In particular, this commitment forces one to adopt a Whiggish approach to the history of mathematics. Two possible resolutions of the difficulty are (1) radical separation - putting the history of mathematics on a separate track from the ordinary course of instruction, and (2) radical accommodation - turning the study of mathematics into the study of mathematical texts.
ERIC Educational Resources Information Center
Hanh, Vu Duc, Ed.
This document gives a listing of mathematical terminology in both the English and Vietnamese languages. Vocabulary used in algebra and geometry is included along with a translation of mathematical symbols. (DT)
ERIC Educational Resources Information Center
Carman, Robert A.
1971-01-01
A mathematical misteak" is an incorrect operation that leads to a correct result. An introduction to the use of the misteak" to emphasize the mathematical operations being taught. Examples and brief explanations of several types of misteaks" are given. (FL)
... this page: //medlineplus.gov/ency/article/001534.htm Mathematics disorder To use the sharing features on this page, please enable JavaScript. Mathematics disorder is a condition in which a child's ...
Druschel, Claudia; Disch, A C; Melcher, I; Engelhardt, T; Luzzati, A; Haas, N P; Schaser, K D
2012-01-01
The descriptions of total spondylectomy and further development of the technique for the treatment of vertebral sarcomas offered for the first time the opportunity to achieve oncologically sufficient resection margins, thereby improving local tumor control and overall survival. Today, single level en bloc spondylectomies are routinely performed and discussed in the literature while only few data are available for multi-level resections. However, due to the topographic vicinity of the spinal cord and large vessels, the multisegmental resections are technically demanding, represent major surgery and only few case reports are available. Surgical options are even more limited in cases of revision surgery and local recurrences when en bloc spondylectomy was considered to be not feasible due to high risk of vital complications in expanding resection margins. Deranged anatomy, implants in situ and extensive intra-/paraspinal scar tissue formation resulting from previously performed approaches and/or radiation are considered the principal complicating factors that usually hold back spine surgeons to perform revision for resection leaving the patient to palliative treatment. We present two patient cases with previously performed piecemeal vertebrectomy in the thoracic spine due to a solitary high-grade spinal sarcoma. After extensive re-staging, both patients underwent a multi (4)-level en bloc spondylectomy in our department (one patient with combined en bloc lung resection). Except a local wound disturbance, there was no severe intra- or postoperative complication. After multilevel en bloc spondylectomy both patients showed a good functional outcome without neurological deficits, except those resulting from oncologically scheduled resection of thoracic nerve roots. After a median follow-up of 13 months, there was no local recurrence or distant metastasis. The reconstruction using a posterior screw rod system that is interconnected to an anterior vertebral body
Hardware description languages
NASA Technical Reports Server (NTRS)
Tucker, Jerry H.
1994-01-01
Hardware description languages are special purpose programming languages. They are primarily used to specify the behavior of digital systems and are rapidly replacing traditional digital system design techniques. This is because they allow the designer to concentrate on how the system should operate rather than on implementation details. Hardware description languages allow a digital system to be described with a wide range of abstraction, and they support top down design techniques. A key feature of any hardware description language environment is its ability to simulate the modeled system. The two most important hardware description languages are Verilog and VHDL. Verilog has been the dominant language for the design of application specific integrated circuits (ASIC's). However, VHDL is rapidly gaining in popularity.
ERIC Educational Resources Information Center
Kilpatrick, Jeremy
2014-01-01
This paper addresses the contested way that ethnomathematics has sometimes been received by mathematicians and others and what that disagreement might suggest about issues in mathematics education; namely, (a) the relation of ethnomathematics to academic mathematics; (b) recent efforts to reform secondary school mathematics so that it prepares…
ERIC Educational Resources Information Center
Kilpatrick, Jeremy
2014-01-01
This paper addresses the contested way that ethnomathematics has sometimes been received by mathematicians and others and what that disagreement might suggest about issues in mathematics education; namely, (a) the relation of ethnomathematics to academic mathematics; (b) recent efforts to reform secondary school mathematics so that it prepares…
Self-Efficacy Beliefs of Prospective Primary Mathematics Teachers about Mathematical Literacy
ERIC Educational Resources Information Center
Yavuz, Gunes; Gunhan, Berna Canturk; Ersoy, Esen; Narli, Serkan
2013-01-01
The aim of this study was to examine the self-efficacy beliefs about mathematical literacy among teachers of primary school mathematics and the relationship between the self-efficacy beliefs and attitudes towards mathematics. To that end, a descriptive research study was conducted with 550 prospective teachers studying primary school mathematics…
Mathematics Teachers' Use of Ethnomathematics Approach in Mathematics Teaching in Edo State
ERIC Educational Resources Information Center
Aikpitanyi, Lucky Aiwuyor; Eraikhuemen, Lucy
2017-01-01
The study investigated mathematics teachers' use of ethnomathematics approach to teaching. Descriptive survey research was used with a target population of all mathematics teacher in all public secondary schools in Oredo, Egor and Ikpoba-Okha local government areas of Edo State out of which 121 mathematics teachers in 42 randomly selected public…
Self-Efficacy Beliefs of Prospective Primary Mathematics Teachers about Mathematical Literacy
ERIC Educational Resources Information Center
Yavuz, Gunes; Gunhan, Berna Canturk; Ersoy, Esen; Narli, Serkan
2013-01-01
The aim of this study was to examine the self-efficacy beliefs about mathematical literacy among teachers of primary school mathematics and the relationship between the self-efficacy beliefs and attitudes towards mathematics. To that end, a descriptive research study was conducted with 550 prospective teachers studying primary school mathematics…
Mathematical model of a flexible space shuttle vehicle
NASA Technical Reports Server (NTRS)
Harvey, C. A.
1972-01-01
The development of a mathematical model of the lateral motion of a flexible space shuttle vehicle during ascent is described. The model was developed to perform control system synthesis using stochastic constrained optimization techniques. The goals of the control system synthesis are to demonstrate the applicability of the techniques and to discover any problems peculiar to the flexible nature of a shuttle vehicle. The equations of motion are derived. A brief description of the generation of numerical data is given. Explicit definitions and numerical values of trajectory data and coefficients appearing in the equations of motion are included.
Developmental Kindergarten: Definition and Description.
ERIC Educational Resources Information Center
Virginia State Dept. of Education, Richmond.
This paper sets forth a definition and operational description of a developmental program that should be of use as a guide, especially to Virginia's teachers and administrators. Also included in the paper are kindergarten curriculum objectives in the areas of language arts, mathematics, science, art, social studies, family life, health, mental…
Mathematical Modeling and Pure Mathematics
ERIC Educational Resources Information Center
Usiskin, Zalman
2015-01-01
Common situations, like planning air travel, can become grist for mathematical modeling and can promote the mathematical ideas of variables, formulas, algebraic expressions, functions, and statistics. The purpose of this article is to illustrate how the mathematical modeling that is present in everyday situations can be naturally embedded in…
Mathematical Modeling and Pure Mathematics
ERIC Educational Resources Information Center
Usiskin, Zalman
2015-01-01
Common situations, like planning air travel, can become grist for mathematical modeling and can promote the mathematical ideas of variables, formulas, algebraic expressions, functions, and statistics. The purpose of this article is to illustrate how the mathematical modeling that is present in everyday situations can be naturally embedded in…
NASA Astrophysics Data System (ADS)
Stöltzner, Michael
Answering to the double-faced influence of string theory on mathematical practice and rigour, the mathematical physicists Arthur Jaffe and Frank Quinn have contemplated the idea that there exists a `theoretical' mathematics (alongside `theoretical' physics) whose basic structures and results still require independent corroboration by mathematical proof. In this paper, I shall take the Jaffe-Quinn debate mainly as a problem of mathematical ontology and analyse it against the backdrop of two philosophical views that are appreciative towards informal mathematical development and conjectural results: Lakatos's methodology of proofs and refutations and John von Neumann's opportunistic reading of Hilbert's axiomatic method. The comparison of both approaches shows that mitigating Lakatos's falsificationism makes his insights about mathematical quasi-ontology more relevant to 20th century mathematics in which new structures are introduced by axiomatisation and not necessarily motivated by informal ancestors. The final section discusses the consequences of string theorists' claim to finality for the theory's mathematical make-up. I argue that ontological reductionism as advocated by particle physicists and the quest for mathematically deeper axioms do not necessarily lead to identical results.
Shi, Runhua; McLarty, Jerry W
2009-10-01
In this article, we introduced basic concepts of statistics, type of distributions, and descriptive statistics. A few examples were also provided. The basic concepts presented herein are only a fraction of the concepts related to descriptive statistics. Also, there are many commonly used distributions not presented herein, such as Poisson distributions for rare events and exponential distributions, F distributions, and logistic distributions. More information can be found in many statistics books and publications.
Factors Influencing Competency in Mathematics Among Entering Elementary Education Majors.
ERIC Educational Resources Information Center
Caraway, Sue Dennis
Relationships among attitude toward mathematics, mathematics background, and junior college transfer versus non-transfer status upon competency in elementary mathematics were investigated using multiple linear regression techniques. Instruments for collecting data included a mathematics placement test, the "Mathematics Attitude Scale" by…
Undergraduate Mathematics Students' Pronumeral Misconceptions
ERIC Educational Resources Information Center
Bardini, Caroline; Vincent, Jill; Pierce, Robyn; King, Deborah
2014-01-01
Despite an emphasis on manipulative algebraic techniques in secondary school algebra, many tertiary mathematics students have mastered these skills without conceptual understanding. A significant number of students with high tertiary entrance ranks enrolled in first semester university mathematics were found to have misconceptions relating to…
ERIC Educational Resources Information Center
McClellan, Kathryn T.
Why mathematics should be learned is discussed. Its role as an important active force in the development of our civilization, and as the most useful subject taught in our schools, next to English, is noted. The primary objective of all mathematics work is to help man study nature, and some practical achievements of this connection are noted.…
ERIC Educational Resources Information Center
Davis, Robert B.
Suggestions are offered for more effective implementation and creativity in developing new mathematics programs. The new mathematics materials and projects have not significantly altered the educational experiences of students because of (1) difficulty in identifying distinctive features of the various projects, (2) widespread assumptions that the…
ERIC Educational Resources Information Center
Flannery, Carol A.
This manuscript provides information and problems for teaching mathematics to vocational education students. Problems reflect applications of mathematical concepts to specific technical areas. The materials are organized into six chapters. Chapter 1 covers basic arithmetic, including fractions, decimals, ratio and proportions, percentages, and…
ERIC Educational Resources Information Center
Prochazka, Helen
2004-01-01
One section of this "scrapbook" section describes Pythagoras' belief in the connections between music and mathematics -- that everything in the universe was a series of harmonies and regulated by music. Another section explains why Phythagoras felt it important for women to be encouraged to learn mathematics. At least 28 women were involved in his…
ERIC Educational Resources Information Center
Flannery, Carol A.
This manuscript provides information and problems for teaching mathematics to vocational education students. Problems reflect applications of mathematical concepts to specific technical areas. The materials are organized into six chapters. Chapter 1 covers basic arithmetic, including fractions, decimals, ratio and proportions, percentages, and…
ERIC Educational Resources Information Center
Langbort, Carol, Ed.; Curtis, Deborah, Ed.
2000-01-01
The focus of this special issue is mathematics education. All articles were written by graduates of the new masters Degree program in which students earn a Master of Arts degree in Education with a concentration in Mathematics Education at San Francisco State University. Articles include: (1) "Developing Teacher-Leaders in a Masters Degree Program…
ERIC Educational Resources Information Center
Martin, Hope
2007-01-01
"Mathematical literacy" implies that a person is able to reason, analyze, formulate, and solve problems in a real-world setting. Mathematically literate individuals are informed citizens and intelligent consumers. They have the ability to interpret and analyze the vast amount of information they are inundated with daily in newspapers, on…
Mathematical Routines For Engineers And Scientists
NASA Technical Reports Server (NTRS)
Kantak, A. V.; Davarian, F.
1987-01-01
Programs for frequently-used mathematical procedures save time. Package contains 16 subroutines. Each separately documented with descriptions of invoking subroutine call, its required parameters, and sample test program. Package written in FORTRAN 77.
Software for English, Mathematics, and Elementary Classes.
ERIC Educational Resources Information Center
Fleharty, Janet
1985-01-01
The paper provides an overview of the uses of software for teaching language arts, mathematics and thinking skills to hearing impaired students. Content area programs are listed with descriptive information, price, and developer name. (Author/CL)
Toward Precision Healthcare: Context and Mathematical Challenges
Colijn, Caroline; Jones, Nick; Johnston, Iain G.; Yaliraki, Sophia; Barahona, Mauricio
2017-01-01
Precision medicine refers to the idea of delivering the right treatment to the right patient at the right time, usually with a focus on a data-centered approach to this task. In this perspective piece, we use the term “precision healthcare” to describe the development of precision approaches that bridge from the individual to the population, taking advantage of individual-level data, but also taking the social context into account. These problems give rise to a broad spectrum of technical, scientific, policy, ethical and social challenges, and new mathematical techniques will be required to meet them. To ensure that the science underpinning “precision” is robust, interpretable and well-suited to meet the policy, ethical and social questions that such approaches raise, the mathematical methods for data analysis should be transparent, robust, and able to adapt to errors and uncertainties. In particular, precision methodologies should capture the complexity of data, yet produce tractable descriptions at the relevant resolution while preserving intelligibility and traceability, so that they can be used by practitioners to aid decision-making. Through several case studies in this domain of precision healthcare, we argue that this vision requires the development of new mathematical frameworks, both in modeling and in data analysis and interpretation. PMID:28377724
Storytelling + Origami = Storigami Mathematics
ERIC Educational Resources Information Center
Mastin, Marla
2007-01-01
This article presents a way to engage students in mathematics learning by using the innovative instructional method of storigami. The author shares reactions from teachers who have used her storigami techniques in their classes and provides an example of storigami using the Norwegian fable "The Dog and the Mountain." (Contains 6 figures.)
Backward Mathematics for Enrichment.
ERIC Educational Resources Information Center
Westcott, Alvin M.; Shuler, Nancy L.
1982-01-01
The use of backward mathematics is promoted as an enrichment strategy which gives pupils the opportunity to generate creative responses that explore many possibilities. It is felt that teachers will find the instructional method a worthwhile innovation, and a technique useful in any curricular area. (MP)
Storytelling + Origami = Storigami Mathematics
ERIC Educational Resources Information Center
Mastin, Marla
2007-01-01
This article presents a way to engage students in mathematics learning by using the innovative instructional method of storigami. The author shares reactions from teachers who have used her storigami techniques in their classes and provides an example of storigami using the Norwegian fable "The Dog and the Mountain." (Contains 6 figures.)
ERIC Educational Resources Information Center
Whitman, David L.; Terry, Ronald E.
1985-01-01
Demonstrating petroleum engineering concepts in undergraduate laboratories often requires expensive and time-consuming experiments. To eliminate these problems, a graphical simulation technique was developed for junior-level laboratories which illustrate vapor-liquid equilibrium and the use of mathematical modeling. A description of this…
ERIC Educational Resources Information Center
Beller, Charley
2013-01-01
The study of definite descriptions has been a central part of research in linguistics and philosophy of language since Russell's seminal work "On Denoting" (Russell 1905). In that work Russell quickly dispatches analyses of denoting expressions with forms like "no man," "some man," "a man," and "every…
ERIC Educational Resources Information Center
Beller, Charley
2013-01-01
The study of definite descriptions has been a central part of research in linguistics and philosophy of language since Russell's seminal work "On Denoting" (Russell 1905). In that work Russell quickly dispatches analyses of denoting expressions with forms like "no man," "some man," "a man," and "every…
Formal description of disease courses.
van der Maas, A A; ter Hofstede, A H
2000-01-01
Patient case analysis is an elementary and crucial process clinicians are confronted with daily. The importance and complexity is reflected in the need to discuss individual patient cases in clinicopathological conferences and the documentation of more than 70,000 patient cases in MEDLINE. This paper introduces DCGL, a technique to model disease course descriptions as present in medical literature. DCGL enables advanced computerised matching of generic disease course descriptions with individual patient case descriptions, a basic function in computerised patient case analysis.
NASA Astrophysics Data System (ADS)
Weidner, Anja; Biermann, Horst
2015-08-01
The class of low-carbon, high-alloy CrMnNi steels exhibits outstanding mechanical properties with respect to high strength and ductility due to either transformation-induced plasticity (TRIP) or twinning-induced plasticity (TWIP) effect depending on chemical composition and deformation temperature. However, the ongoing deformation mechanisms like the formation of stacking faults, martensitic phase transformation or deformation-induced twinning are overlapping and the kinetics of the microstructure evolution are quite complex. Therefore, in addition to macroscopic deformation tests and microstructural investigations by scanning electron microscopy, a combination of several in situ characterization techniques with either high lateral and/or temporal resolution as well as providing integral volume information were chosen in order to give a thoroughly and comprehensive description of the deformation behavior of CrMnNi TRIP/TWIP steels. In addition, the complementary in situ techniques like in situ nanoindentation, micro-digital image correlation, and acoustic emission measurements provide excellent possibility for description of materials behavior on a multiscale level from the submicrometer scale up to the macroscopic range. The results obtained by the complementary techniques can support the future modeling of the deformation behavior of TRIP/TWIP steels dependent on chemical composition, temperature, grain size and grain orientation.
NASA Astrophysics Data System (ADS)
Adulyasas, Lilla
2017-08-01
Technology becomes an important role in teaching and learning mathematics nowadays. Integrating technology in the classroom helps students have better understanding in many of mathematics concepts. One of the major framework for assessing the knowledge of integrating technology with the pedagogy and content in the classroom is Technological Pedagogical and Content Knowledge (TPACK) framework. This study aimed to measure mathematics teachers' TPACK in three southernmost provinces, Thailand and to study on factors influencing their TPACK. A quantitative study was carried out with 210 secondary level mathematics teachers in the three southernmost provinces, Thailand which were random by two stage sampling technique. Data were collected by using a questionnaire to identify the level of mathematics teachers' TPACK and the factors influencing their TPACK. Descriptive statistics, Pearson product moment correlation and multiple regression analysis were used for analysing data. Findings reveal that the mean score of mathematics teachers' TPACK is 3.33 which is in the medium level and the three factors which have positive correlation at .05 level of significant with the level of TPACK are teaching experience factor, individual specialization factor and personal & organization factor. However, there are only two factors influencing mathematics teachers' TPACK. The two factors are individual specialization factor and personal & organization factors. These give better understanding on mathematics teachers' knowledge in integrating technology with the pedagogy and content which will be the important information for improving mathematics teachers' TPACK.
Secondary School Mathematics Curriculum Improvement Study.
ERIC Educational Resources Information Center
Secondary School Mathematics Curriculum Improvement Study, New York, NY.
This bulletin contains: (1) a summary and conclusions of a study of mathematics curricula in Europe and Japan, and (2) a description of beginning efforts to evaluate the Secondary School Mathematics Curriculum Improvement Study (SSMCIS) project. Some of the conclusions of the European and Japanese study are: (1) the study of Euclidean synthetic…
Computer-Game-Based Tutoring of Mathematics
ERIC Educational Resources Information Center
Ke, Fengfeng
2013-01-01
This in-situ, descriptive case study examined the potential of implementing computer mathematics games as an anchor for tutoring of mathematics. Data were collected from middle school students at a rural pueblo school and an urban Hispanic-serving school, through in-field observation, content analysis of game-based tutoring-learning interactions,…
Computer-Game-Based Tutoring of Mathematics
ERIC Educational Resources Information Center
Ke, Fengfeng
2013-01-01
This in-situ, descriptive case study examined the potential of implementing computer mathematics games as an anchor for tutoring of mathematics. Data were collected from middle school students at a rural pueblo school and an urban Hispanic-serving school, through in-field observation, content analysis of game-based tutoring-learning interactions,…
The Mathematics Laboratory in Engineering Studies.
ERIC Educational Resources Information Center
Quesada, Jose Fco. Carballido
1986-01-01
Discusses the need for mathematics laboratories to supplement classroom instruction in mathematics for engineering students. Provides a description of such a laboratory, including a listing of equipment and materials that are recommended. Describes the uses for personal computers and suggests various problems that could be explored in the…
On the Role of Mathematics in Physics
ERIC Educational Resources Information Center
Quale, Andreas
2011-01-01
I examine the association between the observable physical world and the mathematical models of theoretical physics. These models will exhibit many entities that have no counterpart in the physical world, but which are still necessary for the mathematical description of physical systems. Moreover, when the model is applied to the analysis of a…
Ritchie, L.T.; Alpert, D.J.; Burke, R.P.; Johnson, J.D.; Ostmeyer, R.M.; Aldrich, D.C.; Blond, R.M.
1984-03-01
The CRAC2 computer code is a revised version of CRAC (Calculation of Reactor Accident Consequences) which was developed for the Reactor Safety Study. This document provides an overview of the CRAC2 code and a description of each of the models used. Significant improvements incorporated into CRAC2 include an improved weather sequence sampling technique, a new evacuation model, and new output capabilities. In addition, refinements have been made to the atmospheric transport and deposition model. Details of the modeling differences between CRAC2 and CRAC are emphasized in the model descriptions.
Mortimer, Duncan; Segal, Leonie; Sturm, Jonathan
2009-01-01
Background Stroke-specific outcome measures and descriptive measures of health-related quality of life (HRQoL) are unsuitable for informing decision-makers of the broader consequences of increasing or decreasing funding for stroke interventions. The quality-adjusted life year (QALY) provides a common metric for comparing interventions over multiple dimensions of HRQoL and mortality differentials. There are, however, many circumstances when – because of timing, lack of foresight or cost considerations – only stroke-specific or descriptive measures of health status are available and some indirect means of obtaining QALY-weights becomes necessary. In such circumstances, the use of regression-based transformations or mappings can circumvent the failure to elicit QALY-weights by allowing predicted weights to proxy for observed weights. This regression-based approach has been dubbed 'Transfer to Utility' (TTU) regression. The purpose of the present study is to demonstrate the feasibility and value of TTU regression in stroke by deriving transformations or mappings from stroke-specific and generic but descriptive measures of health status to a generic preference-based measure of HRQoL in a sample of Australians with a diagnosis of acute stroke. Findings will quantify the additional error associated with the use of condition-specific to generic transformations in stroke. Methods We used TTU regression to derive empirical transformations from three commonly used descriptive measures of health status for stroke (NIHSS, Barthel and SF-36) to a preference-based measure (AQoL) suitable for attaching QALY-weights to stroke disease states; based on 2570 observations drawn from a sample of 859 patients with stroke. Results Transformations from the SF-36 to the AQoL explained up to 71.5% of variation in observed AQoL scores. Differences between mean predicted and mean observed AQoL scores from the 'severity-specific' item- and subscale-based SF-36 algorithms and from the
SKYMAP system description: Star catalog data base generation and utilization
NASA Technical Reports Server (NTRS)
Gottlieb, D. M.
1979-01-01
The specifications, design, software description, and use of the SKYMAP star catalog system are detailed. The SKYMAP system was developed to provide an accurate and complete catalog of all stars with blue or visual magnitudes brighter than 9.0 for use by attitude determination programs. Because of the large number of stars which are brighter than 9.0 magnitude, efficient techniques of manipulating and accessing the data were required. These techniques of staged distillation of data from a Master Catalog to a Core Catalog, and direct access of overlapping zone catalogs, form the basis of the SKYMAP system. The collection and tranformation of data required to produce the Master Catalog data base is described. The data flow through the main programs and levels of star catalogs is detailed. The mathematical and logical techniques for each program and the format of all catalogs are documented.
ERIC Educational Resources Information Center
Britton, Edward; Raizen, Senta; Kaser, Joyce; Porter, Andrew
When entering this new millennium, educators and researchers need to know much more about how to address the increasingly acute diversity and equity issues in educating children in mathematics and science. This headline was the conclusion of the over 200 distinguished panelists, chairs, discussants, featured speakers, and participants who…
ERIC Educational Resources Information Center
ROSEN, ELLEN F.; STOLUROW, LAWRENCE M.
MANIPULATION OF FRAMES WITHIN PROGRAMED MATHEMATICS TEXTS IN ORDER TO STUDY FOUR VARIABLES YIELDED, IN A PREVIOUSLY REPORTED PAPER, CORRELATIONAL DATA (FOR RELATIVELY SMALL TREATMENT GROUPS) THAT ARE PRESENTED HERE. FIRST, THE ORDER OF PRESENTATION OF PROGRAMED MATERIAL (BEFORE, AFTER, AND WITHOUT CONVENTIONAL INSTRUCTION) HAD NO EFFECT ON…
ERIC Educational Resources Information Center
Buchanan, Anne E.; Romberg, Thomas A.
As part of a 3-year study of arithmetic problem-solving skills in young children, pretests were administered to 180 middle class first grade students. Following each of three instructional units, another achievement test was administered. The three first grade units corresponded to the Developing Mathematical Processes curriculum and involved…
Rendón-Macías, Mario Enrique; Villasís-Keever, Miguel Ángel; Miranda-Novales, María Guadalupe
2016-01-01
Descriptive statistics is the branch of statistics that gives recommendations on how to summarize clearly and simply research data in tables, figures, charts, or graphs. Before performing a descriptive analysis it is paramount to summarize its goal or goals, and to identify the measurement scales of the different variables recorded in the study. Tables or charts aim to provide timely information on the results of an investigation. The graphs show trends and can be histograms, pie charts, "box and whiskers" plots, line graphs, or scatter plots. Images serve as examples to reinforce concepts or facts. The choice of a chart, graph, or image must be based on the study objectives. Usually it is not recommended to use more than seven in an article, also depending on its length.
Threshold Concepts and Undergraduate Mathematics Teaching
ERIC Educational Resources Information Center
Breen, Sinéad; O'Shea, Ann
2016-01-01
Traditionally, many undergraduate mathematics courses have been defined in terms of mathematical content and the techniques in which students should become proficient or theorems they should be able to prove. This can result in a reliance on shallow or rote learning by students, despite the fact that the main goal of a mathematics lecturer is…
Boachie-Adjei, Oheneba; Charles, Gina; Cunningham, Matthew E
2007-02-01
Progressive and/or painful adult spinal deformity in the thoracolumbar and lumbar spine is sometimes treated surgically by long posterior fusions from the thoracic spine down to the pelvis, especially where there is a major thoracic curve component. Recent advances in anterior spinal instrumentation and spinal surgery technique have demonstrated the improved corrective ability offered by anterior stabilization systems, and the added benefit of limiting the number of vertebral fusion levels required for control of the deformity. The "hybrid technique" is a novel use of anterior instrumentation that applies limited anterior instrumentation down to the low lumbar spine (rods and screws), and partially overlapping short-segment posterior instrumentation to the sacrum (pedicle screws and rods). These constructs avoid posterior thoracic instrumentation and fusions, and avoid extension of posterior instrumentation to the pelvis. In the first 10 patients treated using this technique, thoracolumbar and lumbar major curve correction has averaged 71 and 82% in the immediate postoperative period (n = 7), respectively, and 59 and 68% at 2-year follow-up, respectively. The technique is an appealing and attractive alternative for treatment of thoracolumbar and lumbar scoliosis in the adult population, and avoids the requirement for applying spinal fixation to the thoracic spine and the pelvis.
Ilizaliturri, Victor M; Joachin, Pedro; Acuna, Marco
2015-12-01
Pincer impingement is often treated by surgical labral separation from the acetabular rim and rim reduction. A more recent technique the so-called 'over the top' involves reduction of the bony acetabular rim without separation of the labrum. Our purpose is to report mid-term results of the 'over the top' technique. Between January 2006 and January 2013 a consecutive series of patients with femoroacetabular impingement (FAI) diagnosis, treated with the 'over the top' technique were included, using the lateral approach. The Western Ontario and MacMaster (WOMAC) scores were evaluated. Fifty patients (20 males and 30 females) from the Hip and Knee Joint Reconstructive and hip arthroscopy division were included. The average age was 30.5 years old and the average follow-up was 48 months (range 70-90). Preoperative WOMAC average was 42. Post-operative WOMAC was 81.3 (P = 0.01). One patient required an arthroscopic revision due to adherences, but had a full recovery after the revision surgery. The 'over the top' technique is an excellent choice for the treatment of the pincer deformity in the FAI avoiding the injury of the chondrolabral union.
ERIC Educational Resources Information Center
Charconnet, Marie-George
This study describes various patterns of peer tutoring and is based on the use of cultural traditions and endogenous methods, on techniques and equipment acquired from other cultures, on problems presented by the adoption of educational technologies, and on methods needing little sophisticated equipment. A dozen peer tutoring systems are…
ERIC Educational Resources Information Center
McCammon, Richard B.
1979-01-01
The year 1978 marked a continued trend toward practical applications in mathematical geology. Developments included work in interactive computer graphics, factor analysis, the vanishing tons problem, universal kriging, and resource estimating. (BB)
ERIC Educational Resources Information Center
Johnson, Jerry
1997-01-01
Presents 12 questions related to a given real-life situation about a man shaving and the number of hairs in his beard in order to help students see the connection between mathematics and the world around them. (ASK)
ERIC Educational Resources Information Center
Bossé, Michael J.; Adu-Gyamfi, Kwaku; Chandler, Kayla; Lynch-Davis, Kathleen
2016-01-01
Dynamic mathematical environments allow users to reify mathematical concepts through multiple representations, transform mathematical relations and organically explore mathematical properties, investigate integrated mathematics, and develop conceptual understanding. Herein, we integrate Boolean algebra, the functionalities of a dynamic…
ERIC Educational Resources Information Center
Bossé, Michael J.; Adu-Gyamfi, Kwaku; Chandler, Kayla; Lynch-Davis, Kathleen
2016-01-01
Dynamic mathematical environments allow users to reify mathematical concepts through multiple representations, transform mathematical relations and organically explore mathematical properties, investigate integrated mathematics, and develop conceptual understanding. Herein, we integrate Boolean algebra, the functionalities of a dynamic…
Marotta, Nicola; Cosar, Murat; Pimenta, Luiz; Khoo, Larry T
2006-01-15
The authors describe a new paracoccygeal approach to the L5-S1 junction for interbody fusion with transsacral instrumentation. The purpose of this technical note is to demonstrate a novel surgical approach, technique, and instrumentation system for the treatment of L5-S1 instability in degenerative disc disease and spondylolisthesis. This technical note highlights the AxiaLif (TranS1) transsacral system as an alternative method to transforaminal lumbar interbody fusion or posterior lumbar interbody fusion. Via a novel presacral approach corridor, a truly percutaneous L5-S1 discectomy, interbody distraction, and fixation are achieved, and retroperitoneal viscera and dorsal neural elements are avoided. Percutaneous pedicle screw fixation is then used to provide additional stabilization at the treated level. This novel technique of interbody distraction and fusion via a truly percutaneous approach corridor allows for circumferential treatment of the lower lumbar segments with minimal risk to the anterior organs and dorsal neural elements.
Elementary Statistics I--Mathematics 274 Course Syllabus, Fall 2001.
ERIC Educational Resources Information Center
Clark, Deborah L.
This document features the syllabus for a course in Elementary Statistics/Mathematics at Southern University in Baton Rouge, LA. The course textbook, a course description, readings, goals, and course requirements are presented. Basic descriptive analysis and mathematical concepts commonly used in statistics are emphasized in the course. Topics…
Cestari, A; Galli, A C; Sangalli, M N; Zanoni, M; Ferrari, M; Roviaro, G
2017-06-01
Laparoendoscopic single site totally extraperitoneal (TEP) hernia repair showed to be a feasible alternative to conventional laparoscopic hernia repair; nevertheless single site surgery, with the loss of instruments triangulation can be a demanding procedure. To overcome those hurdles, the Single Site® (SS) platform of the da Vinci (DV) Si robotic system enables to perform surgical procedures through a 25-mm skin incision, with a stable 3D vision and restoring an adequate triangulation of the surgical instruments. We present in details the technique and the preliminary results of DV-SS TEP, to our knowledge the first cases reported in literature. In March 2016, three consecutive male patients (mean age 46.6 years-mean BMI 25.3) with bilateral symptomatic inguinal hernia were submitted to DV-SS TEP in our institutions. Feasibility, codification of the technique, operative time and perioperative outcomes were recorded. All the procedures were completed as scheduled, with no conversion to other techniques. Mean operative time was 98.6 min, ranging between 155 and 55 min, reflecting the learning curve of the operating room team on this new procedure. No intraoperative or postoperative complications were experienced and all the patients were discharged within 24 h after surgery. Patients reported satisfactory postoperative course, with no recurrence of inguinal hernia and satisfaction in cosmetic result at 6-month follow-up. DV-SS TEP inguinal hernia repair showed to be feasible and effective surgical option for bilateral groin hernia repair. Patients' outcome was uneventful, with optimal cosmetic results. Further studies comparing this innovative technique to TEP or LESS TEP should be promoted.
Kulwin, Charles; Tubbs, R. Shane; Cohen-Gadol, Aaron A.
2011-01-01
Background: Anterior clinoidectomy is a difficult but important part of surgery for a variety of parasellar, proximal carotid and central skull base pathologies. First developed intradurally nearly 60 years ago, the promotion of an extradural technique decades later offered an approach with a different set of difficulties, risks and benefits. Many recent studies have demonstrated that there is no consensus about the “correct side” of the dura from which to remove the anterior clinoid process in a number of pathologies. Here, we review and compare the current techniques for intra- and extradural clinoidectomy and describe a hybrid alternative technique. Methods: We used a hybrid method to potentially engage the advantages of the intradural and extradural techniques. The hybrid method starts with an extradural sphenoid wing osteotomy to the level of the superior orbital fissure (SOF). The dura is then incised parallel to the sphenoid wing lateral to the SOF, and the need for further bony removal, including clinoidectomy, is assessed after gentle elevation of the frontal lobe and release of cerebrospinal fluid through opening the optico-carotid cisterns and inspection of the pathology in relation to the clinoid. Sylvian fissure may be dissected to relieve retraction on the frontal lobe. Results: The hybrid method allows an early identification of the optic nerve and its protection during clinoidectomy. The operator leaves the dura medial to the SOF intact and the clionoidectomy proceeds in an extradural fashion while intradural inspection periodically is performed to assess the extent of necessary extradural bony removal. Conclusion: The hybrid method theoretically can be used as a versatile method under some circumstances. Cutting the dura along the sphenoid wing will prevent the dural layers from obscuring the clinoid and offers intradural visualization to monitor the lesion and potentially tailor bony removal. PMID:22059135
Mathematical wit and mathematical cognition.
Aberdein, Andrew
2013-04-01
The published works of scientists often conceal the cognitive processes that led to their results. Scholars of mathematical practice must therefore seek out less obvious sources. This article analyzes a widely circulated mathematical joke, comprising a list of spurious proof types. An account is proposed in terms of argumentation schemes: stereotypical patterns of reasoning, which may be accompanied by critical questions itemizing possible lines of defeat. It is argued that humor is associated with risky forms of inference, which are essential to creative mathematics. The components of the joke are explicated by argumentation schemes devised for application to topic-neutral reasoning. These in turn are classified under seven headings: retroduction, citation, intuition, meta-argument, closure, generalization, and definition. Finally, the wider significance of this account for the cognitive science of mathematics is discussed.
The Definition of Mathematics: Philosophical and Pedagogical Aspects
ERIC Educational Resources Information Center
Khait, Alexander
2005-01-01
There is a strange fact that many works written with the purpose to explain what is mathematics, somehow avoid the issue. This paper is aimed at filling this gap. After discussing various descriptions of mathematics as they appear in literature, it is suggested that mathematics is an essentially linguistic activity characterized by association of…
Mathematics Framework for the 2005 National Assessment of Educational Progress
ERIC Educational Resources Information Center
Howe, Roger; Scheaffer, Richard; Lindquist, Mary; Philip, Frank; Halbrook, Arthur
2004-01-01
This document contains the framework and a set of recommendations for the 2005 NAEP mathematics assessment. It includes descriptions of the mathematical content of the test, the types of test questions, and recommendations for administration of the test. In broad terms, this framework attempts to answer the question: What mathematics should be…
Glimm, J.
2009-10-14
Progress for the past decade or so has been extraordinary. The solution of Fermat's Last Theorem [11] and of the Poincare Conjecture [1] have resolved two of the most outstanding challenges to mathematics. For both cases, deep and advanced theories and whole subfields of mathematics came into play and were developed further as part of the solutions. And still the future is wide open. Six of the original seven problems from the Clay Foundation challenge remain open, the 23 DARPA challenge problems are open. Entire new branches of mathematics have been developed, including financial mathematics and the connection between geometry and string theory, proposed to solve the problems of quantized gravity. New solutions of the Einstein equations, inspired by shock wave theory, suggest a cosmology model which fits accelerating expansion of the universe possibly eliminating assumptions of 'dark matter'. Intellectual challenges and opportunities for mathematics are greater than ever. The role of mathematics in society continues to grow; with this growth comes new opportunities and some growing pains; each will be analyzed here. We see a broadening of the intellectual and professional opportunities and responsibilities for mathematicians. These trends are also occuring across all of science. The response can be at the level of the professional societies, which can work to deepen their interactions, not only within the mathematical sciences, but also with other scientific societies. At a deeper level, the choices to be made will come from individual mathematicians. Here, of course, the individual choices will be varied, and we argue for respect and support for this diversity of responses. In such a manner, we hope to preserve the best of the present while welcoming the best of the new.
Malkevitch, J. ); McCarthy, D. )
1990-01-01
The papers in this volume represent talks given at the monthly meetings of the Mathematics Section of the New York Academy of Sciences. They reflect the operating philosophy of the Section in its efforts to make a meaningful contribution to the mathematical life of a community that is exceedingly rich in cultural resources and intellectual opportunities. Each week during the academic year a dazzling abundance of mathematical seminars and colloquia is available in the New York metropolitan area. Most of these offer highly technical treatments intended for specialists. At the New York Academy we try to provide a forum of a different sort, where interesting ideas are presented in a congenial atmosphere to a broad mathematical audience. Many of the Section talks contain substantial specialized material, but we ask our speakers to include a strong expository component aimed at working mathematicians presumed to have no expert knowledge of the topic at hand. We urge speakers to try to provide the motivating interest they themselves would like to find in an introduction to a field other than their own. The same advice has been given to the authors of the present papers, with the goal of producing a collection that will be both accessible and stimulating to mathematical minds at large. We have tried to provide variety in the mathematical vistas offered; both pure and applied mathematics are well represented. Since the papers are presented alphabetically by author, some guidance seems appropriate as to what sorts of topics are treated, and where. There are three papers in analysis: those by Engber, Narici and Beckenstein, and Todd. Engber's deals with complex analysis on compact Riemann surfaces; Narici and Beckenstein provide an introduction to analysis on non-Archimendean fields; Todd surveys an area of contemporary functional analysis.
Stannard, James P; Sathy, Ashoke K; Moeinpour, Fariba; Stewart, Rena L; Volgas, David A
2010-01-01
Use of the Reamer-Irrigator-Aspirator (RIA) as a source of autogenous bone graft in the treatment of nonunions is increasing. We report on our novel technique of using a second filter containing beta-tricalcium phosphate (TCP) as a graft extender while using the RIA system. We also quantify growth factor concentrations in the collections from the TCP filter. A second filter attached in series with the standard RIA filtration system yields TCP with substantial concentrations of bioactive proteins that are equal to those seen in the bone graft that is harvested in the first filter.
Mathematical modelling in developmental biology.
Vasieva, Olga; Rasolonjanahary, Manan'Iarivo; Vasiev, Bakhtier
2013-06-01
In recent decades, molecular and cellular biology has benefited from numerous fascinating developments in experimental technique, generating an overwhelming amount of data on various biological objects and processes. This, in turn, has led biologists to look for appropriate tools to facilitate systematic analysis of data. Thus, the need for mathematical techniques, which can be used to aid the classification and understanding of this ever-growing body of experimental data, is more profound now than ever before. Mathematical modelling is becoming increasingly integrated into biological studies in general and into developmental biology particularly. This review outlines some achievements of mathematics as applied to developmental biology and demonstrates the mathematical formulation of basic principles driving morphogenesis. We begin by describing a mathematical formalism used to analyse the formation and scaling of morphogen gradients. Then we address a problem of interplay between the dynamics of morphogen gradients and movement of cells, referring to mathematical models of gastrulation in the chick embryo. In the last section, we give an overview of various mathematical models used in the study of the developmental cycle of Dictyostelium discoideum, which is probably the best example of successful mathematical modelling in developmental biology.
Fernández-Colino, A; Bermudez, J M; Arias, F J; Quinteros, D; Gonzo, E
2016-04-01
Transversality between mathematical modeling, pharmacology, and materials science is essential in order to achieve controlled-release systems with advanced properties. In this regard, the area of biomaterials provides a platform for the development of depots that are able to achieve controlled release of a drug, whereas pharmacology strives to find new therapeutic molecules and mathematical models have a connecting function, providing a rational understanding by modeling the parameters that influence the release observed. Herein we present a mechanism which, based on reasonable assumptions, explains the experimental data obtained very well. In addition, we have developed a simple and accurate “lumped” kinetics model to correctly fit the experimentally observed drug-release behavior. This lumped model allows us to have simple analytic solutions for the mass and rate of drug release as a function of time without limitations of time or mass of drug released, which represents an important step-forward in the area of in vitro drug delivery when compared to the current state of the art in mathematical modeling. As an example, we applied the mechanism and model to the release data for acetazolamide from a recombinant polymer. Both materials were selected because of a need to develop a suitable ophthalmic formulation for the treatment of glaucoma. The in vitro release model proposed herein provides a valuable predictive tool for ensuring product performance and batch-to-batch reproducibility, thus paving the way for the development of further pharmaceutical devices.
Rispoli, Damian M; Horne, Brandon R; Kryzak, Thomas J; Richardson, Mark W
2010-05-01
Deep soft-tissue defects often present in high-energy trauma and during the surgical treatment of infection. Injuries caused by high-velocity projectiles can create deep soft-tissue defects that are challenging to manage. Persistent, deep wound cavities have been associated with infection and prolonged wound healing. This article presents a technique that marries vacuum-assisted wound closure technology with traditional drains to allow for management of deep soft-tissue cavities. A deep drain was placed in the cavitary lesion with application of a negative-pressure wound therapy sponge in the standard fashion. The deep drain was brought into the sponge and fenestrated as to allow the sponge to evacuate the deep drain. Several illustrative cases are presented. Conversion of deep cavitary defects to superficial defects allowed for delayed primary or secondary closure of the wound defects without the need for increasing the size of the superficial wound to facilitate drainage. Deep infection was also successfully controlled without incurring the additional surgical soft-tissue trauma typical of standard technique. The use of the active deep suction decreases edema and dead space, theoretically reducing the chance of infection. It also prevents premature walling off of deeper cavities, which can occur with the use of vacuum-assisted closure therapy on superficial defects. Our method of wound management allows for the reduction of the deep cavitary defects without delaying wound closure or creating more tissue damage.
NASA Astrophysics Data System (ADS)
McDermott, C. I.; Wenqing, W.; Kolditz, O.
2009-04-01
Exploiting and geo-engineering of fractured rocks in the context of reservoir storage and utilisation is important to applications such as hydrogeology, petroleum geology, geothermal energy, nuclear waste storage and CO2-sequestration. Understanding fluid, mass and energy transport in the three dimensional fracture network is critical to the evaluation planned operating efficiency. Hydraulic, thermal, mechanical and chemical coupled processes under the typical reservoir conditions operate at different scales. Depending on whether the process is continuum dominated (e.g. transfer of stress in the rock body) or discontinuity dominated (e.g. hydraulic transport processes) different methods of numerically investigating and quantifying the system can be applied. A geomechanical facies approach provides the basis for large scale numerical analysis of the coupled processes and prediction of system response. It also provides the basis for a three dimensional holistic understanding of the reservoir systems and the appropriate investigation techniques which could be used to evaluate the capacities of the reservoirs to be investigated as well as appropriate development techniques. Concentrating on the numerical modelling there is often a difficult balance between the numerical stability criteria of the different equation systems which need to be solved to describe the interaction of the dominant processes. The introduction of analytical solutions where possible, functional dependencies and multiple meshes provides on the framework of the geo-mechanical facies concept provides an efficient and stable method for the prediction of the effect of the in situ coupling.
Rochereau, P; Bernardé, A
2012-01-01
This retrospective study documents deep gluteal tenodesis (DGT) used to stabilize coxo- femoral luxation (CFL) in dogs and cats, and to report reluxation rate and clinical outcome after DGT. Medical records (1995-2008) of 65 dogs and cats with traumatic CFL treated by capsulorrhaphy and DGT were reviewed. Animals with radiographic evidence of pre-existing hip dysplasia or articular fractures had been excluded. Reluxation rate and outcome were assessed by clinical examination, performed two and ten weeks postoperatively. Surgical treatment was performed between one and 20 days after the initiating event. No perioperative complications occurred. All hip joints were correctly reduced and stabilized immediately after DGT completion. Except for five patients, placement of the screw was considered correct. In two of these patients, the screws were too long and were protruding into the pelvic canal. In two dogs, the screws were not tightened adequately, and in one dog the screw was too short. Twenty-six dogs and eight cats were re-examined between eight and 13 weeks postoperatively. Re- luxation did not occur in any of them. Outcomes were good in two cases and excellent in 32 cases; all but two had a normal range-of-motion of the reconstructed hip, and were free of lameness and did not show any signs of pain. Traumatic CFL can be stabilized safely and effectively by DGT in dogs and cats. This technique should be considered among other capsular reinforcement techniques in the presence of an intact deep gluteal muscle.
2010-01-01
Background Protein kinases play crucial roles in cell growth, differentiation, and apoptosis. Abnormal function of protein kinases can lead to many serious diseases, such as cancer. Kinase inhibitors have potential for treatment of these diseases. However, current inhibitors interact with a broad variety of kinases and interfere with multiple vital cellular processes, which causes toxic effects. Bioinformatics approaches that can predict inhibitor-kinase interactions from the chemical properties of the inhibitors and the kinase macromolecules might aid in design of more selective therapeutic agents, that show better efficacy and lower toxicity. Results We applied proteochemometric modelling to correlate the properties of 317 wild-type and mutated kinases and 38 inhibitors (12,046 inhibitor-kinase combinations) to the respective combination's interaction dissociation constant (Kd). We compared six approaches for description of protein kinases and several linear and non-linear correlation methods. The best performing models encoded kinase sequences with amino acid physico-chemical z-scale descriptors and used support vector machines or partial least- squares projections to latent structures for the correlations. Modelling performance was estimated by double cross-validation. The best models showed high predictive ability; the squared correlation coefficient for new kinase-inhibitor pairs ranging P2 = 0.67-0.73; for new kinases it ranged P2kin = 0.65-0.70. Models could also separate interacting from non-interacting inhibitor-kinase pairs with high sensitivity and specificity; the areas under the ROC curves ranging AUC = 0.92-0.93. We also investigated the relationship between the number of protein kinases in the dataset and the modelling results. Using only 10% of all data still a valid model was obtained with P2 = 0.47, P2kin = 0.42 and AUC = 0.83. Conclusions Our results strongly support the applicability of proteochemometrics for kinome-wide interaction modelling
NASA Technical Reports Server (NTRS)
Dunn, M. G.; George, W. K.; Rae, W. J.; Woodward, S. H.; Moller, J. C.
1986-01-01
An analytical technique for obtaining the time-resolved heat flux of a turbine blade is applied to the case of a TFE 731-2 hp full-stage rotating turbine. In order to obtain the heat flux values from the thin film gage temperature histories, a finite difference procedure is used to solve the heat equation with variable thermal properties. After setting out the data acquisition and analysis procedures, their application is illustrated for three midspan locations on the blade and operation at the design flow function. Results demonstrate that the magnitude of the heat flux fluctuation due to vane-balde interaction is large by comparison to the time-averaged heat flux at all investigated locations; FFT of a portion of the heat flux record illustrates that the dominant frequencies occur at the wake-cutting frequency and its harmonics.
Mattei, Alberto; Fambrini, Massimiliano; Bargelli, Gianni; Minervini, Andrea; Valeri, Andrea; Pieralli, Annalisa; Andersson, Karin L; Marchionni, Mauro; Scarselli, Gianfranco
2010-01-01
First access is crucial in laparoscopic surgery because of its potentially life-threatening complications. A number of procedures using a variety of instruments have been previously described; however, the safest approach remains uncertain. Herein, we describe a simple and inexpensive method for direct trocar insertion using reusable instruments that was developed over 10 years in a series of 4721 consecutive gynecologic laparoscopic procedures. Observed data revealed that the technique is feasible, rapidly performed, and safe, with a likely cost savings, using a small set of reusable instruments. This procedure should be compared with other access methods in randomized studies to confirm the observed advantages. Copyright © 2010 AAGL. Published by Elsevier Inc. All rights reserved.
2012-01-01
Calcaneal fractures are common injuries involving the hind foot and often a source of significant long-term morbidity. Treatment options have changed throughout the ages from periods of preferred nonoperative management to closed reduction with a mallet, and more recently, open reduction and anatomic internal fixation. The current treatment of choice; however, is often debated, as open management of these fractures carries many risks to include wound breakdown and infection. A less invasive form of surgical management through small incisions, while maintaining the ability to obtain joint congruency, anatomic alignment, and restore calcaneal height and width would be ideal. We propose a novel form of fracture reduction using an inflatable bone tamp and percutaneous fracture fixation. Preoperative planning and experienced fluoroscopy is crucial to successful management using this method. Although we achieved successful radiographic outcome in this case, long-term functional outcome of this technique are yet to be published. PMID:22420710
Labbe, Jean L; Peres, Olivier; Leclair, Olivier; Goulon, Renaud; Scemama, Patrice; Jourdel, François; Bertrou, Véronique; Murgier, Jerome
2016-12-01
Odontoid synchondrosis fractures are rare in children, even though they are the more common cervical fracture in children less than 7 years old. Nonoperative treatment with external orthosis immobilization is the treatment of choice for stable undisplaced or minimally displaced injuries. In unstable fractures, when reduction cannot be achieved or maintained, surgical fixation is recommended. We report a 2-year-old boy with an unstable fracture of the odontoid treated surgically using an absorbable monofilament suture for C1-C2 interlaminar fixation without bone grafting. This suture was strong enough to provide the stability necessary to allow healing of the synchondrosis and the delayed resorption of the suture was followed by complete restoration of the mobility between C1 and C2. This case illustrates that surgical stabilization using an absorbable suture in young children with an unstable odontoid fracture is a safe and effective alternative to other surgical techniques.
NASA Astrophysics Data System (ADS)
Teskey, Wesley J. E.; Chow, Jacky C. K.
2010-09-01
Paragliding is unpowered flight in which pilots rely on their ability to navigate rising currents of air to remain airborne. Paraglider flight performance is an important measure of the capabilities of a particular design of a canopy. Most often, the performance characteristics of a canopy are measured as horizontal velocity vs. vertical velocity for steady state flight in still air. The performance curve created using this approach neglects to take into account the effect which turning has on flight. In contrast, the performance surface created from the research carried out in this paper demonstrates the effect of turning on canopy flight; such a representation of performance is novel to the authors' knowledge. To produce this surface, a flight was conducted in which a paraglider's performance was measured for various steady state velocities and turning rates; the data were then analyzed utilizing mathematical optimization after appropriate calibration corrections were applied.
On the mathematical modeling of wound healing angiogenesis in skin as a reaction-transport process
Flegg, Jennifer A.; Menon, Shakti N.; Maini, Philip K.; McElwain, D. L. Sean
2015-01-01
Over the last 30 years, numerous research groups have attempted to provide mathematical descriptions of the skin wound healing process. The development of theoretical models of the interlinked processes that underlie the healing mechanism has yielded considerable insight into aspects of this critical phenomenon that remain difficult to investigate empirically. In particular, the mathematical modeling of angiogenesis, i.e., capillary sprout growth, has offered new paradigms for the understanding of this highly complex and crucial step in the healing pathway. With the recent advances in imaging and cell tracking, the time is now ripe for an appraisal of the utility and importance of mathematical modeling in wound healing angiogenesis research. The purpose of this review is to pedagogically elucidate the conceptual principles that have underpinned the development of mathematical descriptions of wound healing angiogenesis, specifically those that have utilized a continuum reaction-transport framework, and highlight the contribution that such models have made toward the advancement of research in this field. We aim to draw attention to the common assumptions made when developing models of this nature, thereby bringing into focus the advantages and limitations of this approach. A deeper integration of mathematical modeling techniques into the practice of wound healing angiogenesis research promises new perspectives for advancing our knowledge in this area. To this end we detail several open problems related to the understanding of wound healing angiogenesis, and outline how these issues could be addressed through closer cross-disciplinary collaboration. PMID:26483695
Quotable Quotes in Mathematics
ERIC Educational Resources Information Center
Lo, Bruce W. N.
1983-01-01
As a way to dispel negative feelings toward mathematics, a variety of quotations are given. They are categorized by: what mathematics is, mathematicians, mathematics and other disciplines, different areas of mathematics, mathematics and humor, applications of mathematics, and pure versus applied mathematics. (MNS)
ERIC Educational Resources Information Center
Gafoor, Kunnathodi Abdul; Sarabi, M. K.
2015-01-01
This study relates factors in nature of Mathematics and its teaching learning to student difficulties for diverse mathematics tasks. Descriptive survey was done on a sample of 300 high school students in Kerala with a questionnaire on difficulties in learning. Student perception of difficulty on 26 types of tasks, under five heads that students…
Mathematical String Sculptures: A Case Study in Computationally-Enhanced Mathematical Crafts
ERIC Educational Resources Information Center
Eisenberg, Michael
2007-01-01
Mathematical string sculptures constitute an extremely beautiful realm of mathematical crafts. This snapshot begins with a description of a marvelous (and no longer manufactured) toy called Space Spider, which provided a framework with which children could experiment with string sculptures. Using a computer-controlled laser cutter to create frames…
Mathematical String Sculptures: A Case Study in Computationally-Enhanced Mathematical Crafts
ERIC Educational Resources Information Center
Eisenberg, Michael
2007-01-01
Mathematical string sculptures constitute an extremely beautiful realm of mathematical crafts. This snapshot begins with a description of a marvelous (and no longer manufactured) toy called Space Spider, which provided a framework with which children could experiment with string sculptures. Using a computer-controlled laser cutter to create frames…
Ramalho, M; Herédia, V; de Campos, R O P; de Toni, M; Dale, B M; Semelka, R C
2014-01-01
To implement in-phase and out-of-phase (IP/OP) techniques with Magnetization-Prepared Gradient Recalled Echo (MP-GRE) and to evaluate the feasibility and diagnostic image quality among pre and post-optimized MP-GRE sequences, including patients unable to cooperate with breath-hold requirements. Institutional review board approval with waiver of informed consent was obtained for this HIPAA-compliant retrospective study. Two groups of patients were included in the study, before and after optimization of MP-GRE parameters, with seventy-three (24 noncooperative/49 cooperative) and sixty-four (22 noncooperative/42 cooperative) consecutive patients, respectively. The motion-insensitive sequence used in this study was a single-shot 2D MP-GRE. Two radiologists qualitatively evaluated the sequences to identify the presence of phase cancellation artifact in OP images and to determine image quality, extent of artifacts (respiratory ghosting, bounce-point artifact, spatial misregistration and pixel graininess) and lesion conspicuity on the various sequences. The ability to visually detect liver steatosis and fatty adrenal adenomas was evaluated. Qualitative analyses were compared using the Wilcoxon and Mann-Whitney tests. There were statistically significant differences between all MP-GRE sequences concerning phase cancellation artifact (P<.0001) which was present in MP-GRE OP sequences and negligible to absent in the pre (IP1) and post-optimized (IP2) MP-GRE IP sequences, respectively, in all patients. Bounce point artifacts were significantly more pronounced in MP-GRE IP1 (P<.0001). Spatial misregistration was slightly more prominent in noncooperative patients with MP-GRE IP2 (P=.0027). MP-GRE OP and MP-GRE IP2 showed significantly higher overall image quality (P<.0001). MP-GRE sequences subjectively identified hepatic steatosis (n=20) and adrenal adenomas (n=5) based on signal loss from IP to OP sequence. Single shot IP/OP MP-GRE is feasible and allows motion resistant
The composite sequential clustering technique for analysis of multispectral scanner data
NASA Technical Reports Server (NTRS)
Su, M. Y.
1972-01-01
The clustering technique consists of two parts: (1) a sequential statistical clustering which is essentially a sequential variance analysis, and (2) a generalized K-means clustering. In this composite clustering technique, the output of (1) is a set of initial clusters which are input to (2) for further improvement by an iterative scheme. This unsupervised composite technique was employed for automatic classification of two sets of remote multispectral earth resource observations. The classification accuracy by the unsupervised technique is found to be comparable to that by traditional supervised maximum likelihood classification techniques. The mathematical algorithms for the composite sequential clustering program and a detailed computer program description with job setup are given.
ERIC Educational Resources Information Center
Kennard, Jackie
2007-01-01
One of the most interesting developments in teaching has been the growing importance of the outdoor environment. Whether it be playground, garden or field, the outdoors offers a range of challenging experiences, especially in the delivery of early mathematics. Oral feedback to parents, together with photographic displays, can show them that…
ERIC Educational Resources Information Center
Kennard, Jackie
2007-01-01
One of the most interesting developments in teaching has been the growing importance of the outdoor environment. Whether it be playground, garden or field, the outdoors offers a range of challenging experiences, especially in the delivery of early mathematics. Oral feedback to parents, together with photographic displays, can show them that…
ERIC Educational Resources Information Center
Rogness, Jonathan
2011-01-01
Advances in computer graphics have provided mathematicians with the ability to create stunning visualizations, both to gain insight and to help demonstrate the beauty of mathematics to others. As educators these tools can be particularly important as we search for ways to work with students raised with constant visual stimulation, from video games…
Mertziotis, Nikos; Kozyrakis, Diomidis; Bogris, Elias
2013-11-01
Our objective is to describe a novel ligamentolysis approach using a subcoronal incision technique and to determine its safety and efficacy. During the last 7 years, 82 consecutive patients had penile augmentation surgery. Ligamentolysis, through a lower abdominal incision (V-Y plasty) in the first 35 males, was performed (Group A), followed by circumcision ligamentolysis in the next 47 males (Group B). The operation time, complications, and the preoperative and postoperative values of penile length and girth along with the self-esteem and relations questionnaire score as well as satisfaction score was calculated before and after the surgery, and a comparison was conducted between the groups. The mean age at presentation was 32 years (range: 18-56 years). Seventy-nine patients suffered from penile dysmorphophobia, and three patients had micropenises (length <7.5 cm). The mean surgical times were 150.7 and 125.2 min for Groups A and B, respectively (P=0.005). Postoperatively, four Group A patients and three Group B patients (11% versus 6%, respectively) experienced penile retraction (P=0.453). Hypertrophic scars were observed in 18 men (51%) in the former [corrected] group. In the circumcision group, no major wound complications were recorded. The length and girth improvements between the groups were similar. In terms of satisfaction and SEAR improvement, the resulting difference for both variables favored the circumcision group (P=0.007 and <0.001, respectively). With strict selection criteria, the circumcision ligamentolysis procedure compared to the V-Y plasty demonstrated improved results in terms of safety, operation time, retraction rate and cosmetic appearance without any compromise in the gained penile size.
Kaewpitoon, Soraya J; Kaewpitoon, Natthawut; Rujirakul, Ratana; Ueng-Arporn, Naporn; Matrakool, Likit; Tongtawee, Taweesak
2015-01-01
Opisthorchis viverrini infection is a serious public health problem in Southeast Asia especially in the northeast and north of Thailand. Therefore, a cross-sectional survey using multistage sampling was conducted from the rural communities of Surin province, Thailand, during September 2013 to July 2014. O. viverrini infection was determined using Kato's thick smear technique. Socio-demographic, information resources, and history data were collected using predesigned semi-structured questionnaires. A total of 510 participants completed interviews and had stools collected. Some 32 (6.47%) participants were infected with O. viverrini. The rate was slightly higher in males (6.61%) than females (6.32%). High frequencies were found in the age groups 61-70 (19.4%) and 71-80 years (19.4%), those involved in agriculture (10.5%), and in primary school (10.3%). The distribution of high infection was found in Tha Tum (16.7%) and Sankha district (16.7%), followed by Samrong Thap (13.3%), Si Narong (13.33%), and Buachet district (13.33%). Chi-square testing indicated that age (61-70 and 71-80 year old), education (primary school) and occupation (agriculture), were significantly associated with O. viverrini infection (p-value<0.05). Of 72.6% participants who had past histories with stool examination, 17.0% of them had been infected with O. viverrini and 43.2% treated with praziquantel. This finding confirmed that O. viverrini is still a problem in Surin province, Thailand, and therefore, interventions are urgently required for mass treatment and health education implementation.
Mathematical Creativity and Mathematical Aptitude: A Cross-Lagged Panel Analysis
ERIC Educational Resources Information Center
Tyagi, Tarun Kumar
2016-01-01
Cross-lagged panel correlation (CLPC) analysis has been used to identify causal relationships between mathematical creativity and mathematical aptitude. For this study, 480 8th standard students were selected through a random cluster technique from 9 intermediate and high schools of Varanasi, India. Mathematical creativity and mathematical…
Mathematical Creativity and Mathematical Aptitude: A Cross-Lagged Panel Analysis
ERIC Educational Resources Information Center
Tyagi, Tarun Kumar
2016-01-01
Cross-lagged panel correlation (CLPC) analysis has been used to identify causal relationships between mathematical creativity and mathematical aptitude. For this study, 480 8th standard students were selected through a random cluster technique from 9 intermediate and high schools of Varanasi, India. Mathematical creativity and mathematical…
Mathematics is always invisible, Professor Dowling
NASA Astrophysics Data System (ADS)
Cable, John
2015-09-01
This article provides a critical evaluation of a technique of analysis, the Social Activity Method, recently offered by Dowling (2013) as a `gift' to mathematics education. The method is found to be inadequate, firstly, because it employs a dichotomy (between `expression' and `content') instead of a finer analysis (into symbols, concepts and setting or phenomena), and, secondly, because the distinction between `public' and `esoteric' mathematics, although interesting, is allowed to obscure the structure of the mathematics itself. There is also criticism of what Dowling calls the `myth of participation', which denies the intimate links between mathematics and the rest of the universe that lie at the heart of mathematical pedagogy. Behind all this lies Dowling's `essentially linguistic' conception of mathematics, which is criticised on the dual ground that it ignores the chastening experience of formalism in mathematical philosophy and that linguistics itself has taken a wrong turn and ignores lessons that might be learnt from mathematics education.
Abu-Rustum, Nadeem R; Chi, Dennis S; Sonoda, Yukio; DiClemente, Michael J; Bekker, Genia; Gemignani, Mary; Poynor, Elizabeth; Brown, Carol; Barakat, Richard R
2003-06-01
The objective was to describe the results, technique, and complications of transperitoneal laparoscopic (LSC) pelvic and aortic lymph node dissection (LND) using the argon-beam coagulator (ABC) and monopolar electrosurgical instruments in women with gynecologic malignancies. A retrospective chart review of 114 patients who underwent LSC pelvic and/or aortic LND in addition to other LSC procedures between 1/1994 and 12/2001 was conducted. All intraoperative complications and complications that occurred within the first 30 postoperative days were included. Complications were graded according to an institutional surgical secondary events reference. During the same time period, 89 patients underwent LSC followed immediately by laparotomy that included LND, resulting in a total of 203 cases. These 203 total cases are used as a denominator to determine the etiology of cases converted from LSC to laparotomy. Monopolar electrosurgical instruments or the 10-mm ABC (Conmed) set at 70 W with argon flow of 3-4 L/m min were used for laparoscopic nodal dissection. Sixty-one of 114 (53%) patients underwent pelvic LND, 35 (31%) underwent both pelvic and aortic LND, and 18 (16%) underwent aortic LND only. Mean patient age and body mass index were 53.3 years (range, 16 to 87 years) and 25 (range, 16 to 40), respectively. In addition, the mean number of pelvic and aortic lymph nodes removed was 10.7 (range, 1 to 39) and 5.7 (range, 0 to 21), respectively. The mean estimated blood loss was 151 mL (range, 25 to 600 ml) and the mean hospital stay was 2.8 days (range, 0 to 35 days). Overall, complications occurred in eight (7%) cases. There were no fatal complications, and no patient required conversion to laparotomy due to uncontrollable bleeding from the laparoscopic nodal dissection. Only 17 of 203 (8%) patients required conversion to laparotomy secondary to adhesions and unsatisfactory exposure. Laparoscopic pelvic and aortic LND for gynecologic malignancies can be satisfactorily
Elomaa, E
1985-01-01
The cuff pedestal technique, with which it is possible to use the test animal as its own control both before and after REMs deprivation, was described. The validity of this modified procedure for REMs deprivation was tested with reference to the electrophysiological sleep correlates using 6 adult rats deprived of REMs for 3 days. The stress effects of the cuff pedestal treatment were assessed in terms of adrenal weights in 12 rats. The duration of REMs deprivation in this experiment was 5 days. The effects of REMs deprivation on locomotor activity and food intake were studied in 8 juvenile rats exposed to REMs deprivation by lowering the cuffs for 6 days after 3 baseline days with the cuffs raised. 24 h recordings of meal pattern data were obtained from 8 adult rats during one baseline day, during the first and sixth day of REMs deprivation and during the second day after termination of REMs deprivation. The main results were as follows: The procedure of placing experimentally naive rats on small pedestals surrounded by water inhibited normal food intake for several days. Concomitant weight losses were of the same order as have been reported to occur in control rats on large pedestals. This finding suggests that both the large and small pedestals should be equipped with movable cuffs and that actual deprivation should be started by lowering the cuffs only when the animals have exceeded their original weights. The electrophysiological sleep/waking cycle of rats adapted to living on the pedestal with the cuff raised was similar to that reported in rats under ordinary laboratory conditions. Lowering of the cuffs for 3 days resulted in an almost total disappearance of REMs. A prominent rebound increase of REMs occurred after raising of the cuffs. Rats kept for fourteen days on pedestals with the cuffs raised displayed an increase of about 20% in the weights of the adrenal bodies. A quite similar adrenal hypertrophy, however, also occurs in rats living under enriched
NASA Technical Reports Server (NTRS)
Peuquet, Donna J.
1987-01-01
A new approach to building geographic data models that is based on the fundamental characteristics of the data is presented. An overall theoretical framework for representing geographic data is proposed. An example of utilizing this framework in a Geographic Information System (GIS) context by combining artificial intelligence techniques with recent developments in spatial data processing techniques is given. Elements of data representation discussed include hierarchical structure, separation of locational and conceptual views, and the ability to store knowledge at variable levels of completeness and precision.
NASA Astrophysics Data System (ADS)
Ford, David; Huntsman, Steven
2006-06-01
Thermodynamics (in concert with its sister discipline, statistical physics) can be regarded as a data reduction scheme based on partitioning a total system into a subsystem and a bath that weakly interact with each other. Whereas conventionally, the systems investigated require this form of data reduction in order to facilitate prediction, a different problem also occurs, in the context of communication networks, markets, etc. Such “empirically accessible” systems typically overwhelm observers with the sort of information that in the case of (say) a gas is effectively unobtainable. What is required for such complex interacting systems is not prediction (this may be impossible when humans besides the observer are responsible for the interactions) but rather, description as a route to understanding. Still, the need for a thermodynamical data reduction scheme remains. In this paper, we show how an empirical temperature can be computed for finite, empirically accessible systems, and further outline how this construction allows the age-old science of thermodynamics to be fruitfully applied to them.
Deviren, Vedat; Kuelling, Fabrice A; Poulter, Greg; Pekmezci, Murat
2011-07-01
A retrospective review of a case series. To describe a novel surgical technique for a minimally disruptive lateral transthoracic transpleural approach to treat thoracic disc herniations. Thoracic disc herniation is a relatively uncommon spinal condition, and surgical treatment is indicated for patients with myelopathy or radiculopathy that failed to respond to conservative therapy. Presently there is no consensus about the best approach to address thoracic disc herniations. Using the novel retractor system (MaXcess), the authors describe a novel minimally disruptive approach that allows the surgeons to perform a standard anterior discectomy and fusion with instrumentation while minimizing approach-related morbidity. A series of 12 patients with single-level thoracic disc herniations who underwent anterior spinal cord decompression followed by instrumented fusion through a novel retractor system is being reported. Demographic and radiographic data, perioperative complications, and clinical outcomes were reviewed. Twelve patients were enrolled with an average age of 51 years (range, 23 to 67 y). The average follow-up was 28 months (range, 12 to 33 mo). The average length of hospital stay was 5 days (range, 2 to 12 d). The average preoperative visual analog scale pain score was 9 (range, 7 to 10), which later decreased to 3 (range, 0 to 5) at final follow-up. All patients with myelopathy and/or sphincter dysfunction had significant improvement of their symptoms. One patient had pleural effusion and 1 patient had intercostal neuralgia. Anterior decompression using a transthoracic transpleural approach provides excellent exposure and allows consistent decompression of thoracic disc herniations. This study demonstrated that a new minimally invasive, transthoracic transpleural decompression technique can be safely performed for single-level thoracic disc herniations. The early results showed that this technique allows less dissection, along with the advantages of
Mathematics for modern precision engineering.
Scott, Paul J; Forbes, Alistair B
2012-08-28
The aim of precision engineering is the accurate control of geometry. For this reason, mathematics has a long association with precision engineering: from the calculation and correction of angular scales used in surveying and astronomical instrumentation to statistical averaging techniques used to increase precision. This study illustrates the enabling role the mathematical sciences are playing in precision engineering: modelling physical processes, instruments and complex geometries, statistical characterization of metrology systems and error compensation.
Mathematical Modeling of Diverse Phenomena
NASA Technical Reports Server (NTRS)
Howard, J. C.
1979-01-01
Tensor calculus is applied to the formulation of mathematical models of diverse phenomena. Aeronautics, fluid dynamics, and cosmology are among the areas of application. The feasibility of combining tensor methods and computer capability to formulate problems is demonstrated. The techniques described are an attempt to simplify the formulation of mathematical models by reducing the modeling process to a series of routine operations, which can be performed either manually or by computer.
Donato, David I.
2012-01-01
This report presents the mathematical expressions and the computational techniques required to compute maximum-likelihood estimates for the parameters of the National Descriptive Model of Mercury in Fish (NDMMF), a statistical model used to predict the concentration of methylmercury in fish tissue. The expressions and techniques reported here were prepared to support the development of custom software capable of computing NDMMF parameter estimates more quickly and using less computer memory than is currently possible with available general-purpose statistical software. Computation of maximum-likelihood estimates for the NDMMF by numerical solution of a system of simultaneous equations through repeated Newton-Raphson iterations is described. This report explains the derivation of the mathematical expressions required for computational parameter estimation in sufficient detail to facilitate future derivations for any revised versions of the NDMMF that may be developed.
ERIC Educational Resources Information Center
Barrera-Osorio, Felipe; Garcia-Moreno, Vicente; Patrinos, Harry Anthony; Porta, Emilio
2011-01-01
The Oaxaca-Blinder technique was originally used in labor economics to decompose earnings gaps and to estimate the level of discrimination. It has been applied since in other social issues, including education, where it can be used to assess how much of a gap is due to differences in characteristics (explained variation) and how much is due to…
ERIC Educational Resources Information Center
Barrera-Osorio, Felipe; Garcia-Moreno, Vicente; Patrinos, Harry Anthony; Porta, Emilio
2011-01-01
The Oaxaca-Blinder technique was originally used in labor economics to decompose earnings gaps and to estimate the level of discrimination. It has been applied since in other social issues, including education, where it can be used to assess how much of a gap is due to differences in characteristics (explained variation) and how much is due to…
Mathematics Curriculum Guide. Mathematics IV.
ERIC Educational Resources Information Center
Gary City Public School System, IN.
GRADES OR AGES: Grade 12. SUBJECT MATTER: Mathematics. ORGANIZATION AND PHYSICAL APPEARANCE: The subject matter is presented in four columns: major areas, significant outcomes, observations and suggestions, and films and references. The topics include: sets-relations-functions, circular functions, graphs of circular functions, inverses of circular…
Dilemma in Teaching Mathematics
ERIC Educational Resources Information Center
Md Kamaruddin, Nafisah Kamariah; Md Amin, Zulkarnain
2012-01-01
The challenge in mathematics education is finding the best way to teach mathematics. When students learn the reasoning and proving in mathematics, they will be proficient in mathematics. Students must know mathematics before they can apply it. Symbolism and logic is the key to both the learning of mathematics and its effective application to…
Mathematics Worth Teaching, Mathematics Worth Understanding.
ERIC Educational Resources Information Center
Romberg, Thomas A.; Kaput, James J.
This chapter examines the scope of the mathematical content educators expect students to understand after they have participated in mathematics courses. It is organized under four headings: (1) Traditional School Mathematics, to clarify what the shift is away from; (2) Mathematics as Human Activity, to portray the direction the shift is toward;…
Mathematical Literacy and Standardized Mathematical Assessments
ERIC Educational Resources Information Center
Matteson, Shirley M.
2006-01-01
Mathematical literacy is an important skill that is gaining the attention of mathematics educators. Students are increasingly challenged on standardized assessments to read, create, use, and comprehend numerous mathematical representations as a way of demonstrating mathematical literacy. Test items assessing algebra concepts from the Texas…
Teachers' Mathematics as Mathematics-at-Work
ERIC Educational Resources Information Center
Bednarz, Nadine; Proulx, Jérôme
2017-01-01
Through recognising mathematics teachers as professionals who use mathematics in their workplace, this article traces a parallel between the mathematics enacted by teachers in their practice and the mathematics used in workplaces found in studies of professionals (e.g. nurses, engineers, bankers). This parallel is developed through the five…
Teaching Mathematical Modeling in Mathematics Education
ERIC Educational Resources Information Center
Saxena, Ritu; Shrivastava, Keerty; Bhardwaj, Ramakant
2016-01-01
Mathematics is not only a subject but it is also a language consisting of many different symbols and relations. Taught as a compulsory subject up the 10th class, students are then able to choose whether or not to study mathematics as a main subject. The present paper discusses mathematical modeling in mathematics education. The article provides…
Applied mathematical problems in modern electromagnetics
NASA Astrophysics Data System (ADS)
Kriegsman, Gregory
1994-05-01
We have primarily investigated two classes of electromagnetic problems. The first contains the quantitative description of microwave heating of dispersive and conductive materials. Such problems arise, for example, when biological tissue are exposed, accidentally or purposefully, to microwave radiation. Other instances occur in ceramic processing, such as sintering and microwave assisted chemical vapor infiltration and other industrial drying processes, such as the curing of paints and concrete. The second class characterizes the scattering of microwaves by complex targets which possess two or more disparate length and/or time scales. Spatially complex scatterers arise in a variety of applications, such as large gratings and slowly changing guiding structures. The former are useful in developing microstrip energy couplers while the later can be used to model anatomical subsystems (e.g., the open guiding structure composed of two legs and the adjoining lower torso). Temporally complex targets occur in applications involving dispersive media whose relaxation times differ by orders of magnitude from thermal and/or electromagnetic time scales. For both cases the mathematical description of the problems gives rise to complicated ill-conditioned boundary value problems, whose accurate solutions require a blend of both asymptotic techniques, such as multiscale methods and matched asymptotic expansions, and numerical methods incorporating radiation boundary conditions, such as finite differences and finite elements.
Mathematical modelling of animate and intentional motion.
Rittscher, Jens; Blake, Andrew; Hoogs, Anthony; Stein, Gees
2003-01-01
Our aim is to enable a machine to observe and interpret the behaviour of others. Mathematical models are employed to describe certain biological motions. The main challenge is to design models that are both tractable and meaningful. In the first part we will describe how computer vision techniques, in particular visual tracking, can be applied to recognize a small vocabulary of human actions in a constrained scenario. Mainly the problems of viewpoint and scale invariance need to be overcome to formalize a general framework. Hence the second part of the article is devoted to the question whether a particular human action should be captured in a single complex model or whether it is more promising to make extensive use of semantic knowledge and a collection of low-level models that encode certain motion primitives. Scene context plays a crucial role if we intend to give a higher-level interpretation rather than a low-level physical description of the observed motion. A semantic knowledge base is used to establish the scene context. This approach consists of three main components: visual analysis, the mapping from vision to language and the search of the semantic database. A small number of robust visual detectors is used to generate a higher-level description of the scene. The approach together with a number of results is presented in the third part of this article. PMID:12689374
Identification and Description of Geophysical Techniques.
1980-11-01
for reaction with groundwater and pollutants. Shales and clays, for example, have the po- tential for concentrating certain ions by the processes of...8217tured shale unit. Geophysical expression of lithology can include acoustic velocity, electrical resistivity, spontaneous potential, density, gamma...the travel time required for acoustic compressional waves, generated in the earth by a near-surface explosion, mechanical impact, or vibration , to
Galilei invariant technique for quantum system description
Kamuntavičius, Gintautas P.
2014-04-15
Problems with quantum systems models, violating Galilei invariance are examined. The method for arbitrary non-relativistic quantum system Galilei invariant wave function construction, applying a modified basis where center-of-mass excitations have been removed before Hamiltonian matrix diagonalization, is developed. For identical fermion system, the Galilei invariant wave function can be obtained while applying conventional antisymmetrization methods of wave functions, dependent on single particle spatial variables.
Profile of mathematics anxiety of 7th graders
NASA Astrophysics Data System (ADS)
Udil, Patrisius Afrisno; Kusmayadi, Tri Atmojo; Riyadi
2017-08-01
Mathematics anxiety is one of the important factors affect students mathematics achievement. This present research investigates profile of students' mathematics anxiety. This research focuses on analysis and description of students' mathematics anxiety level generally and its dominant domain and aspect. Qualitative research with case study strategy was used in this research. Subject in this research involved 15 students of 7th grade chosen with purposive sampling. Data in this research were students' mathematics anxiety scale result, interview record, and observation result during both mathematics learning activity and test. They were asked to complete mathematics anxiety scale before interviewed and observed. The results show that generally students' mathematics anxiety was identified in the moderate level. In addition, students' mathematics anxiety during mathematics test was identified in the high level, but it was in the moderate level during mathematics learning process. Based on the anxiety domain, students have a high mathematics anxiety on cognitive domain, while it was in the moderate level for psychological and physiological domains. On the other hand, it was identified in low level for psychological domain during mathematics learning process. Therefore, it can be concluded that students have serious and high anxiety regarding mathematics on the cognitive domain and mathematics test aspect.
Mathematical models in medicine: Diseases and epidemics
Witten, M.
1987-01-01
This volume presents the numerous applications of mathematics in the life sciences and medicine, and demonstrates how mathematics and computers have taken root in these fields. The work covers a variety of techniques and applications including mathematical and modelling methodology, modelling/simulation technology, and philosophical issues in model formulation, leading to speciality medical modelling, artificial intelligence, psychiatric models, medical decision making, and molecular modelling.
Integrating Literature in Mathematics: A Teaching Technique for Mathematics Teachers
ERIC Educational Resources Information Center
Ruiz, Elsa C.; Thornton, Jenifer Salter; Cuero, Kimberley K.
2010-01-01
The integration of content areas is not a new concept (Moyer, 2000). Integration is promoted by many teacher educators because of its benefits for learners of all ages and backgrounds (Burns, 2005; Douville, Pugalee, & Wallace, 2003; Pica, 2002). Literacy in general, but reading in particular, is important across the content areas. Mathematics…
Integrating Literature in Mathematics: A Teaching Technique for Mathematics Teachers
ERIC Educational Resources Information Center
Ruiz, Elsa C.; Thornton, Jenifer Salter; Cuero, Kimberley K.
2010-01-01
The integration of content areas is not a new concept (Moyer, 2000). Integration is promoted by many teacher educators because of its benefits for learners of all ages and backgrounds (Burns, 2005; Douville, Pugalee, & Wallace, 2003; Pica, 2002). Literacy in general, but reading in particular, is important across the content areas. Mathematics…
Uses and abuses of mathematics in biology.
May, Robert M
2004-02-06
In the physical sciences, mathematical theory and experimental investigation have always marched together. Mathematics has been less intrusive in the life sciences, possibly because they have until recently been largely descriptive, lacking the invariance principles and fundamental natural constants of physics. Increasingly in recent decades, however, mathematics has become pervasive in biology, taking many different forms: statistics in experimental design; pattern seeking in bioinformatics; models in evolution, ecology, and epidemiology; and much else. I offer an opinionated overview of such uses--and abuses.
Auteur Description: From the Director's Creative Vision to Audio Description
ERIC Educational Resources Information Center
Szarkowska, Agnieszka
2013-01-01
In this report, the author follows the suggestion that a film director's creative vision should be incorporated into Audio description (AD), a major technique for making films, theater performances, operas, and other events accessible to people who are blind or have low vision. The author presents a new type of AD for auteur and artistic films:…
Auteur Description: From the Director's Creative Vision to Audio Description
ERIC Educational Resources Information Center
Szarkowska, Agnieszka
2013-01-01
In this report, the author follows the suggestion that a film director's creative vision should be incorporated into Audio description (AD), a major technique for making films, theater performances, operas, and other events accessible to people who are blind or have low vision. The author presents a new type of AD for auteur and artistic films:…
Computation and graphics in mathematical research. Progress report, June 1, 1991--May 31, 1992
Hoffman, D.A.; Spruck, J.
1992-08-13
This report discusses: The description of the GANG Project and results for prior research; the center for geometry, analysis, numerics and graphics; description of GANG Laboratory; software development at GANG; and mathematical and scientific research activities.
Mathematics and academic diversity in Japan.
Woodward, John; Ono, Yumiko
2004-01-01
Japanese education has been the subject of considerable research and educational commentary in the United States over the last 20 years. Since the early 1990s, there has been increased interest in Japanese methods for teaching mathematics, and the Third International Mathematics and Science Study has accelerated American interest in Japanese methods. Observational studies, teacher and student surveys, and analyses of classroom videotapes have provided a rich picture of how the Japanese teach the whole class. However, little has been written about how academically low-achieving math students fare in Japanese schools. This article briefly summarizes Japanese methods for teaching mathematics and describes how the educational system addresses academic diversity. It concludes with a description of a method for teaching mathematics that some Japanese mathematics educators feel has promise for students with learning disabilities.
Promoting Mathematical Argumentation
ERIC Educational Resources Information Center
Rumsey, Chepina; Langrall, Cynthia W.
2016-01-01
The Standards for Mathematical Practice (SMP) in the Common Core State Standards for Mathematics (CCSSM) (CCSSI 2010) highlight the mathematical habits that educators should be fostering in mathematics classrooms throughout K-grade 12 education. That argumentation and discourse are important components of developing mathematically proficient…
Authenticity of Mathematical Modeling
ERIC Educational Resources Information Center
Tran, Dung; Dougherty, Barbara J.
2014-01-01
Some students leave high school never quite sure of the relevancy of the mathematics they have learned. They fail to see links between school mathematics and the mathematics of everyday life that requires thoughtful decision making and often complex problem solving. Is it possible to bridge the gap between school mathematics and the mathematics in…
Promoting Mathematical Argumentation
ERIC Educational Resources Information Center
Rumsey, Chepina; Langrall, Cynthia W.
2016-01-01
The Standards for Mathematical Practice (SMP) in the Common Core State Standards for Mathematics (CCSSM) (CCSSI 2010) highlight the mathematical habits that educators should be fostering in mathematics classrooms throughout K-grade 12 education. That argumentation and discourse are important components of developing mathematically proficient…
Mathematical Programming Models in Educational Planning.
ERIC Educational Resources Information Center
McNamara, James F.
This document begins by defining and discussing educational planning. A brief overview of mathematical programing with an explanation of the general linear programing model is then provided. Some recent applications of mathematical programing techniques to educational planning problems are reviewed, and their implications for educational research…
The reasonable effectiveness of mathematics in the natural sciences
NASA Astrophysics Data System (ADS)
Harvey, Alex
2011-12-01
Mathematics and its relation to the physical universe have been the topic of speculation since the days of Pythagoras. Several different views of the nature of mathematics have been considered: Realism—mathematics exists and is discovered; Logicism—all mathematics may be deduced through pure logic; Formalism—mathematics is just the manipulation of formulas and rules invented for the purpose; Intuitionism—mathematics comprises mental constructs governed by self evident rules. The debate among the several schools has major importance in understanding what Eugene Wigner called, The Unreasonable Effectiveness of Mathematics in the Natural Sciences. In return, this `Unreasonable Effectiveness' suggests a possible resolution of the debate in favor of Realism. The crucial element is the extraordinary predictive capacity of mathematical structures descriptive of physical theories.
The College Entrance Examination Board and Mathematics Education.
ERIC Educational Resources Information Center
Jones, Chancey O.; Valentine, John A.
1984-01-01
To help explain the relationship between board activities and mathematics education today, the creation and evolution of the College Board are described. The development of the Advanced Placement computer science course description and examination are noted particularly. (MNS)
Number Sense in the Elementary School Mathematics Classroom.
ERIC Educational Resources Information Center
McBride, John W.; Lamb, Charles E.
1986-01-01
The number sense program in Texas was developed to help motivate students to learn mathematics and to literally develop "number sense." A description of the program, a 70-item exercise (with answers), and teaching tips are provided. (JN)
Values taught, values learned, attitude and performance in mathematics
NASA Astrophysics Data System (ADS)
Limbaco, K. S. A.
2015-03-01
The purpose of the study was to identify, describe and find the relationship among values taught, values learned, attitude and performance in mathematics. The researcher used descriptive-correlational method of research to gather information and to describe the nature of situation. The following instruments were used in this study: Math Attitude Inventory, Inventory of Values Taught and Learned which were content validated by experts in the field of Mathematics, Values and Education. Generally, most of the values were taught by the teachers. All of the values were learned by the students. The following got the highest mean ratings for values taught: moral strength, sharing, charity, valuing life, love of God, truth and honesty, reason, alternativism and articulation. The following got highest mean ratings for values learned: patience/tolerance, sharing, charity, valuing life, faith, love of God, truth and honesty, analogical thinking, confidence and individual liberty. Majority of the respondents have moderately positive attitude towards mathematics. Positive statements in the Mathematics Attitude Inventory are "Generally true" while negative statements are "Neutral." In conclusion, values were taught by mathematics teacher, thus, learned by the students. Therefore, mathematics is very much related to life. Values can be learned and strengthened through mathematics; there is a significant relationship between values taught by the teachers and values learned by the students and attitude towards mathematics and performance in mathematics; values taught does not affect attitude towards mathematics and performance in mathematics. A student may have a positive attitude towards mathematics or have an exemplary performance in mathematics even if the mathematics teacher did not teach values; values learned does not affect attitude towards mathematics and performance in mathematics. A student may have a positive attitude towards mathematics or have an exemplary performance
Handbook of Forecasting Techniques. Part 2. Description of 31 Techniques
1977-08-01
failure torminnl nodes. The state of the project at each nodu Is specified and the expected profit, cash flow, and probability that the brunch will be taken...theories of psychological growth (Maslow, Graves, etc,), images (Polak, Boulding, Markley, etc.), myths (Campbell), life ways (Morris, Mitchell), and so...invented by market analysts to indicate the general area of correlating psychological factors with consumer behavior. The rationale underlying the use of
The Mathematics of Starry Nights
ERIC Educational Resources Information Center
Barman, Farshad
2008-01-01
The mathematics for finding and plotting the locations of stars and constellations are available in many books on astronomy, but the steps involve mystifying and fragmented equations, calculations, and terminology. This paper will introduce an entirely new unified and cohesive technique that is easy to understand by mathematicians, and simple…
Mathematical Modeling of Chemical Stoichiometry
ERIC Educational Resources Information Center
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…
Mathematical Modeling of Chemical Stoichiometry
ERIC Educational Resources Information Center
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…
The Mathematics of Starry Nights
ERIC Educational Resources Information Center
Barman, Farshad
2008-01-01
The mathematics for finding and plotting the locations of stars and constellations are available in many books on astronomy, but the steps involve mystifying and fragmented equations, calculations, and terminology. This paper will introduce an entirely new unified and cohesive technique that is easy to understand by mathematicians, and simple…
NASA Astrophysics Data System (ADS)
Kasturirangan, Rajesh
2014-07-01
Mathematics is a human pursuit. Whether the truths of mathematics lie outside the human mind or emerge out of it, the actual practice of mathematics is conducted by human beings. In other words, human mathematics is the only kind of mathematics that we can pursue and human mathematics has to be built on top of cognitive capacities that are possessed by all human beings. Another way of stating the same claim is that mathematics is experienced by human beings using their cognitive capacities. This paper argues that exploring the experience of mathematics is a useful way to make headway on the foundations of mathematics. Focusing on the experience of mathematics is an empirical approach to the study of mathematics that sidesteps some of the thorniest debates from an earlier era about Platonism and Formalism in the foundations of mathematics.
NASA Astrophysics Data System (ADS)
Rahayu, D. V.
2017-02-01
This study was intended to figure out basic teaching skills of Mathematics Department Students of STKIP Garut at Field Experience Program in academic year 2014/2015. This study was qualitative research with analysis descriptive technique. Instrument used in this study was observation sheet to measure basic teaching mathematics skills. The result showed that ability of content mastery and explaining skill were in average category. Questioning skill, conducting variations skill and conducting assessment skill were in good category. Managing classroom skill and giving motivation skill were in poor category. Based on the result, it can be concluded that the students’ basic teaching skills weren’t optimal. It is recommended for the collegians to get lesson with appropriate strategy so that they can optimize their basic teaching skills.
Mathematics Education Computer Software and Mathematics Teachers.
ERIC Educational Resources Information Center
Ozgun-Koca, S. Asli
2000-01-01
Presents results from a study that uses questionnaires to ask mathematics teachers' (N=64) opinions about mathematics education computer software. Indicates that respondents overwhelmingly favored discovery and remediation as the purpose of using software in mathematics classrooms. Teachers believed that real world situations and multiple…
Mathematical Story: A Metaphor for Mathematics Curriculum
ERIC Educational Resources Information Center
Dietiker, Leslie
2015-01-01
This paper proposes a theoretical framework for interpreting the content found in mathematics curriculum in order to offer teachers and other mathematics educators comprehensive conceptual tools with which to make curricular decisions. More specifically, it describes a metaphor of "mathematics curriculum as story" and defines and…
Mathematical Modelling Approach in Mathematics Education
ERIC Educational Resources Information Center
Arseven, Ayla
2015-01-01
The topic of models and modeling has come to be important for science and mathematics education in recent years. The topic of "Modeling" topic is especially important for examinations such as PISA which is conducted at an international level and measures a student's success in mathematics. Mathematical modeling can be defined as using…
Discrete Mathematics and the Secondary Mathematics Curriculum.
ERIC Educational Resources Information Center
Dossey, John
Discrete mathematics, the mathematics of decision making for finite settings, is a topic of great interest in mathematics education at all levels. Attention is being focused on resolving the diversity of opinion concerning the exact nature of the subject, what content the curriculum should contain, who should study that material, and how that…
The Necessary Teaching Competences for Mathematics Teachers in Middle Schools
ERIC Educational Resources Information Center
Alnoor, A. G.; xiang, G. Y.
2007-01-01
The professional competences of middle school mathematics teachers has been identified, also the significance extent of such competences for chinese and yemenies mathematics teachers has been studied. The researcher used descriptive research approach. The study data collected from Specialist educators and teachers experts to determine the…
Success of Online Mathematics Courses at the Community College Level
ERIC Educational Resources Information Center
Lee, Lisa S.
2011-01-01
Low success rates in online mathematics courses at the community college level have raised concerns. The purpose of this study was to investigate the factors that contribute to student success in online mathematics courses at community colleges. The non-experimental quantitative design began with descriptive statistics to explore the quantitative…
Mathematical modeling of forest fire initiation in three dimensional setting
Valeriy Perminov
2007-01-01
In this study, the assignment and theoretical investigations of the problems of forest fire initiation were carried out, including development of a mathematical model for description of heat and mass transfer processes in overterrestrial layer of atmosphere at crown forest fire initiation, taking into account their mutual influence. Mathematical model of forest fire...
Motivational Classroom Climate for Learning Mathematics: A Reversal Theory Perspective
ERIC Educational Resources Information Center
Lewis, Gareth
2015-01-01
In this article, a case is made that affect is central in determining students' experience of learning or not learning mathematics. I show how reversal theory (Apter, 2001), and particularly its taxonomy of motivations and emotions, provides a basis for a thick description of students' experiences of learning in a mathematics classroom. Using data…
Motivational Classroom Climate for Learning Mathematics: A Reversal Theory Perspective
ERIC Educational Resources Information Center
Lewis, Gareth
2015-01-01
In this article, a case is made that affect is central in determining students' experience of learning or not learning mathematics. I show how reversal theory (Apter, 2001), and particularly its taxonomy of motivations and emotions, provides a basis for a thick description of students' experiences of learning in a mathematics classroom. Using data…
Success of Online Mathematics Courses at the Community College Level
ERIC Educational Resources Information Center
Lee, Lisa S.
2011-01-01
Low success rates in online mathematics courses at the community college level have raised concerns. The purpose of this study was to investigate the factors that contribute to student success in online mathematics courses at community colleges. The non-experimental quantitative design began with descriptive statistics to explore the quantitative…
[Cambridge Conference on School Mathematics Feasibility Studies 9-13.
ERIC Educational Resources Information Center
Cambridge Conference on School Mathematics, Newton, MA.
These materials are a part of a series of studies sponsored by the Cambridge Conference on School Mathematics which reflects the ideas of CCSM regarding the goals and objectives for school mathematics K-12. Feasibility Studies 9-13 contain a wide range of topics. The following are the titles and brief descriptions of these studies. Number…
Mathematics Framework for the 2007 National Assessment of Educational Progress
ERIC Educational Resources Information Center
Howe, Roger; Scheaffer, Richard; Lindquist, Mary
2006-01-01
This document contains the framework and a set of recommendations for the NAEP 2007 mathematics assessment, which will assess student achievement nationally and state-by-state, as well as in select urban districts, in grades 4 and 8. It includes descriptions of the mathematical content of the test, the types of test questions, and recommendations…
A Topological Technique for Regionalization.
ERIC Educational Resources Information Center
Brantingham, Patricia L.; Brantingham, Paul J.
1978-01-01
Presents a mathematical technique for building perceptual models of urban areas. Uses techniques to model perceptual neighborhoods within a city and to explore how residential burglary rates vary between the interiors and borders of the neighborhood. (Author/MA)
Rival approaches to mathematical modelling in immunology
NASA Astrophysics Data System (ADS)
Andrew, Sarah M.; Baker, Christopher T. H.; Bocharov, Gennady A.
2007-08-01
In order to formulate quantitatively correct mathematical models of the immune system, one requires an understanding of immune processes and familiarity with a range of mathematical techniques. Selection of an appropriate model requires a number of decisions to be made, including a choice of the modelling objectives, strategies and techniques and the types of model considered as candidate models. The authors adopt a multidisciplinary perspective.
ERIC Educational Resources Information Center
Awofala, Adeneye O. A.
2017-01-01
The study investigated mathematical proficiency as related to gender and performance in mathematics among 400 Nigerian senior secondary school students from 10 elitist senior secondary schools in Lagos State using the quantitative research method within the blueprint of descriptive survey design. Data collected were analysed using the descriptive…
Classroom Instruction and Students' Attitudes Towards Mathematics
ERIC Educational Resources Information Center
Tessema, Taddesse G.
2010-01-01
This quantitative study examined the association between classroom instruction and students' attitudes towards mathematics at the secondary level. Data were collected through a Likert-type survey of Hope High School students and then analyzed for statistical significance by utilizing descriptive statistics, tests of significance, and correlation…
Qualitative Graphing: A Construction in Mathematics.
ERIC Educational Resources Information Center
Narode, Ronald
This document argues that qualitative graphing is an effective introduction to mathematics as a construction for communication of ideas involving quantitative relationships. It is suggested that with little or no prior knowledge of Cartesian coordinates or analytic descriptions of graphs using equations students can successfully grasp concepts of…
Provocative Mathematics Questions: Drawing Attention to a Lack of Attention
ERIC Educational Resources Information Center
Klymchuk, Sergiy
2015-01-01
The article investigates the role of attention in the reflective thinking of school mathematics teachers. It analyses teachers' ability to pay attention to detail and "use" their mathematical knowledge. The vast majority of teachers can be expected to have an excellent knowledge of mathematical techniques. The question examined here is…
Provocative Mathematics Questions: Drawing Attention to a Lack of Attention
ERIC Educational Resources Information Center
Klymchuk, Sergiy
2015-01-01
The article investigates the role of attention in the reflective thinking of school mathematics teachers. It analyses teachers' ability to pay attention to detail and "use" their mathematical knowledge. The vast majority of teachers can be expected to have an excellent knowledge of mathematical techniques. The question examined here is…
Three essays in mathematical finance
NASA Astrophysics Data System (ADS)
Wang, Ruming
This dissertation uses mathematical techniques to solve three problems in mathematical finance. The first two problems are on model-independent pricing and hedging of financial derivatives. We use asymptotic expansions to express derivative prices and implied volatilities. Then just by using the first few terms in the expansions, we get simple and accurate formulas, which can also help us find connections between different products. The last problem is on optimal trading strategies in a limit order book. Under a very general setup, we solve explicitly for a dynamic decision problem involving choosing between limit order and market order.
Chinese Calendar and Mathematical Astronomy
NASA Astrophysics Data System (ADS)
Sun, Xiaochun
The Chinese calendar (li 历) was a system of mathematical astronomy that included mathematical techniques for the computation of celestial movements. It was the basis for producing astronomical ephemerides and annual almanacs. Calendar making started early in China. Since the Great Inception calendar reform in 104 BC, China has produced about 100 calendars (astronomical systems). The focus of calendar making was the prediction of solar, lunar, and planetary motions. As astronomy developed, new observational discoveries were incorporated into the calendar to make the system more precise. The history of astronomy in ancient China was largely a history of calendar making.
NASA Astrophysics Data System (ADS)
Swoger, Jim; Martinez-Corral, Manuel; Huisken, Jan; Stelzer, Ernst H. K.
2002-09-01
The applicability of optical scanning holography (OSH) to the field of microscopic imaging for biological applications is assessed. A generalized mathematical description of OSH that takes into account polarization effects, high numerical apertures, and generalized illumination wave fronts is presented. This description is used to show that the proposed single-beam scanning technique relaxes the restrictions under which OSH functions correctly compared with the conventional double-beam scanning method. It is also shown that, although in general OSH is restricted to thin samples, this condition can be relaxed in nonrefracting fluorescence samples, which are of importance in biological microscopy.
Structural damage identification using mathematical optimization techniques
NASA Technical Reports Server (NTRS)
Shen, Mo-How Herman
1991-01-01
An identification procedure is proposed to identify damage characteristics (location and size of the damage) from dynamic measurements. This procedure was based on minimization of the mean-square measure of difference between measurement data (natural frequencies and mode shapes) and the corresponding predictions obtained from the computational model. The procedure is tested for simulated damage in the form of stiffness changes in a simple fixed free spring mass system and symmetric cracks in a simply supported Bernoulli Euler beam. It is shown that when all the mode information is used in the identification procedure it is possible to uniquely determine the damage properties. Without knowing the complete set of modal information, a restricted region in the initial data space has been found for realistic and convergent solution from the identification process.
Some Techniques for the Mathematics Classroom
ERIC Educational Resources Information Center
Schoenfeld, Alan H.
1977-01-01
Eight suggestions for surmounting barriers between the student and the class teacher are given and briefly discussed: class evaluations, alternate class structure, student-written notes, in-class "experiments," quizzes without trauma, the class dummy, "programmed" spontaneity, and "treats." (DT)
Mathematic-computational modeling for the calculations involved in the Stern-Volmer theory
NASA Astrophysics Data System (ADS)
Thadeu, Felipe C.; Silva, Juliana A.; Silva, Dilson
2016-12-01
The present work consists of the description of a mathematic-computational routine to process the calculation, statistics, plotting graphs and then show binding constants of ligands to transport proteins, as described by the Stern-Volmer Theory. The quenching of fluorescence technique used to analyze samples produces a great amount of data to build spectral plots. The aim of the work is to develop a computational tool which simplify, turn confident and make agile to deal with the great mass of data generated by the fluorescence spectroscopy equipment.
A mathematical simulation model of a 1985-era tilt-rotor passenger aircraft
NASA Technical Reports Server (NTRS)
Mcveigh, M. A.; Widdison, C. A.
1976-01-01
A mathematical model for use in real-time piloted simulation of a 1985-era tilt rotor passenger aircraft is presented. The model comprises the basic six degrees-of-freedom equations of motion, and a large angle of attack representation of the airframe and rotor aerodynamics, together with equations and functions used to model turbine engine performance, aircraft control system and stability augmentation system. A complete derivation of the primary equations is given together with a description of the modeling techniques used. Data for the model is included in an appendix.
ASTP ranging system mathematical model
NASA Technical Reports Server (NTRS)
Ellis, M. R.; Robinson, L. H.
1973-01-01
A mathematical model is presented of the VHF ranging system to analyze the performance of the Apollo-Soyuz test project (ASTP). The system was adapted for use in the ASTP. The ranging system mathematical model is presented in block diagram form, and a brief description of the overall model is also included. A procedure for implementing the math model is presented along with a discussion of the validation of the math model and the overall summary and conclusions of the study effort. Detailed appendices of the five study tasks are presented: early late gate model development, unlock probability development, system error model development, probability of acquisition and model development, and math model validation testing.
NASA Astrophysics Data System (ADS)
Tegmark, Max
2014-02-01
The world can be described using mathematical equations and numbers, but why does maths do it so well? In his new book Our Mathematical Universe, a section of which is abridged and edited here, Max Tegmark makes the radical proposal that our reality isn't just described by mathematics - it is mathematics.
ERIC Educational Resources Information Center
Lo, Jane-Jane; And Others
Calls for increased student involvement in mathematics classroom learning situations are due primarily to the recognition that a traditional lecture/demonstration format within school mathematics instruction is not effective in fostering and promoting students' problem-solving abilities, mathematical reasoning power, and mathematical communication…
Students as Mathematics Consultants
ERIC Educational Resources Information Center
Jensen, Jennifer L.
2013-01-01
If students are going to develop reasoning and thinking skills, use their mathematical knowledge, and recognize the relevance of mathematics in their lives, they need to experience mathematics in meaningful ways. Only then will their mathematical skills be transferrable to all other parts of their lives. To promote such flexible mathematical…
Mathematics Lessons without ...
ERIC Educational Resources Information Center
Cross, Kath; Hibbs, John
2006-01-01
In the Association of Teachers of Mathematics (ATM) Easter conference, 2006, the authors presented a list of important aspects of mathematics lessons, recommended for students to have a positive attitude to mathematics and for teachers to acquire effective teaching. The following are discussed in detail: (1) Mathematics lessons without good…
ERIC Educational Resources Information Center
Cain, David
2007-01-01
This article presents the first part of the closing address given by the author to the 2007 Association of Teachers of Mathematics (ATM) Easter conference at Loughborough. In his closing address, the author focuses on functioning mathematically as opposed to functional mathematics. His view of functional mathematics is that the focus is on someone…
ERIC Educational Resources Information Center
Ricks, Thomas E.
2010-01-01
Mathematics is motivating; at least, it should be. I argue that mathematical activity is an inherently attractive enterprise for human beings because as intellectual organisms, we are naturally enticed by the intellectual stimulation of mathematizing, and, as social beings, we are drawn to the socializing aspects of mathematical activity. These…
Computer Mathematics: An Introduction.
ERIC Educational Resources Information Center
New York City Board of Education, Brooklyn, NY. Div. of Curriculum and Instruction.
This document describes a mathematics course that uses the computer to solve mathematics problems. It was developed to be used with students who have completed at least one year of general mathematics or are not achieving success in the traditional mathematics program. The course is intended to review, reinforce, and extend concepts included in…
ERIC Educational Resources Information Center
Mumcu, Hayal Yavuz
2016-01-01
The purpose of this theoretical study is to explore the relationships between the concepts of using mathematics in the daily life, mathematical applications, mathematical modelling, and mathematical literacy. As these concepts are generally taken as independent concepts in the related literature, they are confused with each other and it becomes…
Transforming Primary Mathematics
ERIC Educational Resources Information Center
Askew, Mike
2011-01-01
What is good mathematics teaching? What is mathematics teaching good for? Who is mathematics teaching for? These are just some of the questions addressed in "Transforming Primary Mathematics", a highly timely new resource for teachers which accessibly sets out the key theories and latest research in primary maths today. Under-pinned by findings…
ERIC Educational Resources Information Center
Cain, David
2007-01-01
This article presents the first part of the closing address given by the author to the 2007 Association of Teachers of Mathematics (ATM) Easter conference at Loughborough. In his closing address, the author focuses on functioning mathematically as opposed to functional mathematics. His view of functional mathematics is that the focus is on someone…
Mathematics Lessons without ...
ERIC Educational Resources Information Center
Cross, Kath; Hibbs, John
2006-01-01
In the Association of Teachers of Mathematics (ATM) Easter conference, 2006, the authors presented a list of important aspects of mathematics lessons, recommended for students to have a positive attitude to mathematics and for teachers to acquire effective teaching. The following are discussed in detail: (1) Mathematics lessons without good…
Students as Mathematics Consultants
ERIC Educational Resources Information Center
Jensen, Jennifer L.
2013-01-01
If students are going to develop reasoning and thinking skills, use their mathematical knowledge, and recognize the relevance of mathematics in their lives, they need to experience mathematics in meaningful ways. Only then will their mathematical skills be transferrable to all other parts of their lives. To promote such flexible mathematical…
Transforming Primary Mathematics
ERIC Educational Resources Information Center
Askew, Mike
2011-01-01
What is good mathematics teaching? What is mathematics teaching good for? Who is mathematics teaching for? These are just some of the questions addressed in "Transforming Primary Mathematics", a highly timely new resource for teachers which accessibly sets out the key theories and latest research in primary maths today. Under-pinned by findings…
Granularity analysis for mathematical proofs.
Schiller, Marvin R G
2013-04-01
Mathematical proofs generally allow for various levels of detail and conciseness, such that they can be adapted for a particular audience or purpose. Using automated reasoning approaches for teaching proof construction in mathematics presupposes that the step size of proofs in such a system is appropriate within the teaching context. This work proposes a framework that supports the granularity analysis of mathematical proofs, to be used in the automated assessment of students' proof attempts and for the presentation of hints and solutions at a suitable pace. Models for granularity are represented by classifiers, which can be generated by hand or inferred from a corpus of sample judgments via machine-learning techniques. This latter procedure is studied by modeling granularity judgments from four experts. The results provide support for the granularity of assertion-level proofs but also illustrate a degree of subjectivity in assessing step size.
NASA Astrophysics Data System (ADS)
Milaturrahmah, Naila; Mardiyana, Pramudya, Ikrar
2017-08-01
This 21st century demands competent human resources in science, technology, engineering design and mathematics so that education is expected to integrate the four disciplines. This paper aims to describe the importance of STEM as mathematics learning approach in Indonesia in the 21st century. This paper uses a descriptive analysis research method, and the method reveals that STEM education growing in developed countries today can be a framework for innovation mathematics in Indonesia in the 21st century. STEM education integrate understanding of science, math skills, and the available technology with the ability to perform engineering design process. Implementation of mathematics learning with STEM approach makes graduates trained in using of mathematics knowledge that they have to create innovative products that are able to solve the problems that exist in society.
ERIC Educational Resources Information Center
Salani, End
2013-01-01
Lesson starts are transitional events which may cause management problems for teachers. This study sought junior secondary school mathematics teachers' beliefs about calculator use in mathematics instruction in Botswana and was descriptive in nature adopting a survey design. The sample of seventeen (17) mathematics teachers from four (4) junior…
Learning to Solve Story Problems--Supporting Transitions between Reality and Mathematics
ERIC Educational Resources Information Center
Große, Cornelia S.
2014-01-01
Applying mathematics to real problems is increasingly emphasized in school education; however, it is often complained that many students are not able to solve mathematical problems embedded in contexts. In order to solve story problems, a transition from a textual description to a mathematical notation has to be found, intra-mathematical…
ERIC Educational Resources Information Center
Wasserman, Nicholas H.
2015-01-01
The work that mathematics teachers do is frequently mathematical in nature and different from other professions. Understanding and describing common ways that teachers draw upon their content knowledge in the practice of teaching is important. Building on the descriptions by McCrory et al. ("Journal for Research in Mathematics Education"…
ERIC Educational Resources Information Center
Wasserman, Nicholas H.
2015-01-01
The work that mathematics teachers do is frequently mathematical in nature and different from other professions. Understanding and describing common ways that teachers draw upon their content knowledge in the practice of teaching is important. Building on the descriptions by McCrory et al. ("Journal for Research in Mathematics Education"…
ERIC Educational Resources Information Center
Silver, Edward A.; Lane, Suzanne
Recent reports on mathematics education reform have focused the attention of educational practitioners and policymakers on new goals for mathematics education and new descriptions of mathematical proficiency. QUASAR is a national project (Quantitative Understanding: Amplifying Student Achievement and Reasoning) designed to improve the mathematics…
Learning to Solve Story Problems--Supporting Transitions between Reality and Mathematics
ERIC Educational Resources Information Center
Große, Cornelia S.
2014-01-01
Applying mathematics to real problems is increasingly emphasized in school education; however, it is often complained that many students are not able to solve mathematical problems embedded in contexts. In order to solve story problems, a transition from a textual description to a mathematical notation has to be found, intra-mathematical…
ERIC Educational Resources Information Center
Peschek, Werner; Schneider, Edith
2001-01-01
Discusses descriptive and normative perspectives of mathematics and of (general) mathematics education which can be found in the didactic literature. Contemplates and evaluates the use of computer algebra systems and offers suggestions for basic knowledge and basic skills in a modern technology-supported mathematics classroom. (Contains 12…
Mathematical modelling of flow distribution in the human cardiovascular system
NASA Technical Reports Server (NTRS)
Sud, V. K.; Srinivasan, R. S.; Charles, J. B.; Bungo, M. W.
1992-01-01
The paper presents a detailed model of the entire human cardiovascular system which aims to study the changes in flow distribution caused by external stimuli, changes in internal parameters, or other factors. The arterial-venous network is represented by 325 interconnected elastic segments. The mathematical description of each segment is based on equations of hydrodynamics and those of stress/strain relationships in elastic materials. Appropriate input functions provide for the pumping of blood by the heart through the system. The analysis employs the finite-element technique which can accommodate any prescribed boundary conditions. Values of model parameters are from available data on physical and rheological properties of blood and blood vessels. As a representative example, simulation results on changes in flow distribution with changes in the elastic properties of blood vessels are discussed. They indicate that the errors in the calculated overall flow rates are not significant even in the extreme case of arteries and veins behaving as rigid tubes.
Mathematical modelling of flow distribution in the human cardiovascular system
NASA Technical Reports Server (NTRS)
Sud, V. K.; Srinivasan, R. S.; Charles, J. B.; Bungo, M. W.
1992-01-01
The paper presents a detailed model of the entire human cardiovascular system which aims to study the changes in flow distribution caused by external stimuli, changes in internal parameters, or other factors. The arterial-venous network is represented by 325 interconnected elastic segments. The mathematical description of each segment is based on equations of hydrodynamics and those of stress/strain relationships in elastic materials. Appropriate input functions provide for the pumping of blood by the heart through the system. The analysis employs the finite-element technique which can accommodate any prescribed boundary conditions. Values of model parameters are from available data on physical and rheological properties of blood and blood vessels. As a representative example, simulation results on changes in flow distribution with changes in the elastic properties of blood vessels are discussed. They indicate that the errors in the calculated overall flow rates are not significant even in the extreme case of arteries and veins behaving as rigid tubes.
Minimal dynamical description of eye movements
NASA Astrophysics Data System (ADS)
Specht, Juan I.; Dimieri, Leonardo; Urdapilleta, Eugenio; Gasaneo, Gustavo
2017-02-01
In this paper we have addressed the question of whether a simple set of functions being the solution of a model, namely the damped harmonic oscillator with a general driving force, can satisfactorily describe data corresponding to ocular movements produced during a visual search task. Taking advantage of its mathematical tractability, we first focused on the simplest driving force compatible to the experimental data, a step-like activation. Under this hypothesis we were able to further simplify the system, once data from several experiments were fitted, producing an essentially parameter-free model that we plan to use in future applications. To increase the quality of the description of individual movements, we expanded the complexity in the forcing term and solved the inverse problem by using a proper mathematical formalism. Furthermore, additional terms, those arising from ocular drift and tremor, may be included within the same mathematical approach.
Salt Block II: description and results
Hohlfelder, J.J.
1980-06-01
A description of and results from the Salt Block II experiment, which involved the heating of and measurement of water transport within a large sample of rock salt, are presented. These results include the measurement of water released into a heated borehole in the sample as well as measured temperatures within the salt. Measured temperatures are compared with the results of a mathematical model of the experiment.
Schaffner, M
1990-01-01
The skill of writing job descriptions begins with an understanding of the advantages, as well as the basic elements, of a well written description. The end result should be approved and updated as needed. Having a better understanding of this process makes writing the job description a challenge rather than a chore.
Dense Granular Avalanches: Mathematical Description and Experimental Validation
NASA Astrophysics Data System (ADS)
Tai, Y.-C.; Hutter, K.; Gray, J. M. N. T.
Snow avalanches, landslides, rock falls and debris flows are extremely dangerous and destructive natural phenomena. The frequency of occurrence and amplitudes of these disastrous events appear to have increased in recent years perhaps due to recent climate warming. The events endanger the personal property and infra-structure in mountainous regions. For example, from the winters 1940/41 to 1987/88 more than 7000 snow avalanches occurred in Switzerland with damaged property leading to a total of 1269 deaths. In February 1999, 36 people were buried by a single avalanche in Galtür, Austria. In August 1996, a very large debris flow in middle Taiwan resulted in 51 deaths, 22 lost and an approximate property damage of more than 19 billion NT dollars (ca. 600 million US dollars) [18]. In Europe, a suddenly released debris flow in North Italy in August 1998 buried 5 German tourists on the Superhighway "Brenner-Autobahn". The topic has gained so much significance that in 1990 the United Nations declared the International Decade for Natural Disasters Reduction (IDNDR); Germany has its own Deutsches IDNDR-Komitee für Katastrophenvorbeugung e.V. Special conferences are devoted to the theme, e.g., the CALAR conference on Avalanches, Landslides, Rock Falls and Debris Flows (Vienna, January 2000), INTERPRAEVENT, annual conferences on the protection of habitants from floods, debris flows and avalanches, special conferences on debris flow hazard mi tigation and those exclusively on Avalanches.
NASA Astrophysics Data System (ADS)
Ilyas, Muhammad; Salwah
2017-02-01
The type of this research was experiment. The purpose of this study was to determine the difference and the quality of student's learning achievement between students who obtained learning through Realistic Mathematics Education (RME) approach and students who obtained learning through problem solving approach. This study was a quasi-experimental research with non-equivalent experiment group design. The population of this study was all students of grade VII in one of junior high school in Palopo, in the second semester of academic year 2015/2016. Two classes were selected purposively as sample of research that was: year VII-5 as many as 28 students were selected as experiment group I and VII-6 as many as 23 students were selected as experiment group II. Treatment that used in the experiment group I was learning by RME Approach, whereas in the experiment group II by problem solving approach. Technique of data collection in this study gave pretest and posttest to students. The analysis used in this research was an analysis of descriptive statistics and analysis of inferential statistics using t-test. Based on the analysis of descriptive statistics, it can be concluded that the average score of students' mathematics learning after taught using problem solving approach was similar to the average results of students' mathematics learning after taught using realistic mathematics education (RME) approach, which are both at the high category. In addition, It can also be concluded that; (1) there was no difference in the results of students' mathematics learning taught using realistic mathematics education (RME) approach and students who taught using problem solving approach, (2) quality of learning achievement of students who received RME approach and problem solving approach learning was same, which was at the high category.
Design Features of Pedagogically-Sound Software in Mathematics.
ERIC Educational Resources Information Center
Haase, Howard; And Others
Weaknesses in educational software currently available in the domain of mathematics are discussed. A technique that was used for the design and production of mathematics software aimed at improving problem-solving skills which combines sound pedagogy and innovative programming is presented. To illustrate the design portion of this technique, a…
Mathematics Coursework Regulates Growth in Mathematics Achievement
ERIC Educational Resources Information Center
Ma, Xin; Wilkins, Jesse L. M.
2007-01-01
Using data from the Longitudinal Study of American Youth (LSAY), we examined the extent to which students' mathematics coursework regulates (influences) the rate of growth in mathematics achievement during middle and high school. Graphical analysis showed that students who started middle school with higher achievement took individual mathematics…
Mathematics for Language, Language for Mathematics
ERIC Educational Resources Information Center
Prochazkova, Lenka Tejkalova
2013-01-01
The author discusses the balance and mutual influence of the language of instruction and mathematics in the context of CLIL, Content and Language Integrated Learning. Different aspects of the relationship of language and Mathematics teaching and learning are discussed: the benefits of using a foreign language of instruction, as well as the…
Mathematics Coursework Regulates Growth in Mathematics Achievement
ERIC Educational Resources Information Center
Ma, Xin; Wilkins, Jesse L. M.
2007-01-01
Using data from the Longitudinal Study of American Youth (LSAY), we examined the extent to which students' mathematics coursework regulates (influences) the rate of growth in mathematics achievement during middle and high school. Graphical analysis showed that students who started middle school with higher achievement took individual mathematics…
Mathematics and Sports. Mathematical World. Volume 3.
ERIC Educational Resources Information Center
Sadovskii, L. E.; Sadovskii, A. L.
This volume contains some examples of mathematical applications in sports. Sports discussed include tennis, figure skating, gymnastics, track and field, soccer, skiing, hockey, and swimming. Problems and situations are posed and answers with thorough explanations are provided. Chapters include: (1) Mathematics and Sports; (2) What Is Applied…
Discover Mathematical Knowledge through Recreational Mathematics Problems
ERIC Educational Resources Information Center
Sodhi, Amar
2004-01-01
The way in which a mathematical problem was used as a vehicle to introduce the joy of mathematical research to a high school student is demonstrated. The student was interested in learning about other classical problems delighting an eager high school student.
NASA Astrophysics Data System (ADS)
Jannah, R. R.; Apriliya, S.; Karlimah
2017-03-01
This study aims to develop alternative instructional design based of barriers learning which identified by developing mathematical connection capabilities to the material unit of distance and speed. The research was conducted in the fifth grade elementary school Instructional design is complemented with a hypothetical learning trajectory in the form of a pedagogical didactic anticipation. The method used is descriptive method with qualitative approach. Techniques data collection used were observation, interviews, and documentation. The instrument used the researchers themselves are equipped with an instrument written test. The data were analyzed qualitatively to determine the student learning obstacles, then arrange hypothetical learning trajectory and pedagogical didactic anticipation. Learning obstacle are identified, it is learning obstacle related the connections between mathematical topics, learning obstacle related with other disciplines, and learning obstacle related with everyday life. The results of this research are improvement and development of didactic design in mathematics which has activities mathematical connection to the material unit of distance and speed in elementary school. The learning activities are carried out is using varied methods include method lectures, demonstrations, practice and exercise, as well as using the modified instructional media.
ERIC Educational Resources Information Center
Barwell, Richard
2013-01-01
Climate change is one of the most pressing issues of the 21st Century. Mathematics is involved at every level of understanding climate change, including the description, prediction and communication of climate change. As a highly complex issue, climate change is an example of "post-normal" science -- it is urgent, complex and involves a…
Studies in Mathematics Education. Volume 2. The Teaching of Basic Sciences, Mathematics.
ERIC Educational Resources Information Center
Morris, Robert, Ed.
This volume was geared to answering the question, does the teaching of mathematics correspond to the needs of the majority of pupils and the society. There are three types of chapters: (1) descriptions of goals reflecting some need of society; (2) case studies of national goal setting; and (3) a summary of the May 1980 meeting of the United…
ERIC Educational Resources Information Center
Barwell, Richard
2013-01-01
Climate change is one of the most pressing issues of the 21st Century. Mathematics is involved at every level of understanding climate change, including the description, prediction and communication of climate change. As a highly complex issue, climate change is an example of "post-normal" science -- it is urgent, complex and involves a…
2009-01-01
The scope of this book does not allow a complete description of the many techniques available for purification and treatment of reagents for facilitating immunoassays in general. There is a large amount of literature covering techniques, and this can be consulted for specific problems. The examination of many of the catalogs produced by commercial companies is useful as they often include good technical sections describing methods using their products. This chapter contains the practical basics of conjugation (a large field in itself), and details other immediately useful techniques that might be first desired in starting an ELISA. The book Antibodies: A Laboratory Manual (1) should be regarded as definitive in the laboratory because it is extremely "digestible" and covers a large field of methods, all of which are relevant to ELISA.
Developing My Mathematics Identity
ERIC Educational Resources Information Center
Gonzalez, Lidia
2016-01-01
Assuming the role of storyteller, the author uses her experiences as a graduate student and beginning teacher to reflect critically on issues related to mathematics, mathematics education, gender, and diversity.
Developing My Mathematics Identity
ERIC Educational Resources Information Center
Gonzalez, Lidia
2016-01-01
Assuming the role of storyteller, the author uses her experiences as a graduate student and beginning teacher to reflect critically on issues related to mathematics, mathematics education, gender, and diversity.
Students' Mathematical Noticing
ERIC Educational Resources Information Center
Lobato, Joanne; Hohensee, Charles; Rhodehamel, Bohdan
2013-01-01
Even in simple mathematical situations, there is an array of different mathematical features that students can attend to or notice. What students notice mathematically has consequences for their subsequent reasoning. By adapting work from both cognitive science and applied linguistics anthropology, we present a focusing framework, which treats…
Mathematics, Programming, and STEM
ERIC Educational Resources Information Center
Yeh, Andy; Chandra, Vinesh
2015-01-01
Learning mathematics is a complex and dynamic process. In this paper, the authors adopt a semiotic framework (Yeh & Nason, 2004) and highlight programming as one of the main aspects of the semiosis or meaning-making for the learning of mathematics. During a 10- week teaching experiment, mathematical meaning-making was enriched when primary…
ERIC Educational Resources Information Center
Walshaw, Margaret
2014-01-01
This paper explores contemporary thinking about learning mathematics, and within that, social justice within mathematics education. The discussion first looks at mechanisms offered by conventional explanations on the emancipatory project and then moves towards more recent insights developed within mathematics education. Synergies are drawn between…
ERIC Educational Resources Information Center
Gallian, Joseph A., Ed.
2010-01-01
"Mathematics and Sports", edited by Joseph A. Gallian, gathers 25 articles that illuminate the power and role of mathematics in the worlds of professional and recreational play. Divided into sections by the kind of sports, the book offers source materials for classroom use and student projects. Readers will encounter mathematical ideas from an…
Mathematics in Masons' Workplace
ERIC Educational Resources Information Center
Moreira, Darlinda; Pardal, Eugénia
2012-01-01
This paper presents masons' professional practices, which are related to mathematics. It aims to contribute to the area of adult mathematics education and to enlarge knowledge about how mathematics is used at the workplace. Methodologically it was followed an ethnographic approach. The key informants of the study were four masons aged between 40…
Mathematics and Mobile Learning
ERIC Educational Resources Information Center
Sayed, Fayez
2015-01-01
The wide range of Mathematical Apps targeting different mathematical concepts and the various types of mobile devices available present a demanding and challenging problem to the teaching and learning in the field of mathematics. In an attempt to address this issue, a few Apps were selected, implemented and tested in this work. [For complete…
Mathematics and Global Survival.
ERIC Educational Resources Information Center
Schwartz, Richard H.
This resource was written to provide students with an awareness of critical issues facing the world today. In courses for college students, it can motivate their study of mathematics, teach them how to solve mathematical problems related to current global issues, provide coherence to mathematical studies through a focus on issues of human…
ERIC Educational Resources Information Center
Martin, Tami S.; Speer, William R.
2009-01-01
This article describes features, consistent messages, and new components of "Mathematics Teaching Today: Improving Practice, Improving Student Learning" (NCTM 2007), an updated edition of "Professional Standards for Teaching Mathematics" (NCTM 1991). The new book describes aspects of high-quality mathematics teaching; offers a model for observing,…
Mathenger Hunt: Mathematics Matters.
ERIC Educational Resources Information Center
Falba, Christy J.; Weiss, Maria J.
1991-01-01
Presented is an activity which shows how mathematics is used in real life and helps to establish a need for mathematics in students' futures. Adapted from a scavenger-hunt idea, this activity helps students to discover that almost every career makes use of mathematics. (KR)
ERIC Educational Resources Information Center
Toumasis, Charalampos
2004-01-01
Emphasis on problem solving and mathematical modeling has gained considerable attention in the last few years. Connecting mathematics to other subjects and to the real world outside the classroom has received increased attention in mathematics programs. This article describes an application of simple differential equations in the field of…
ERIC Educational Resources Information Center
Walshaw, Margaret
2014-01-01
This paper explores contemporary thinking about learning mathematics, and within that, social justice within mathematics education. The discussion first looks at mechanisms offered by conventional explanations on the emancipatory project and then moves towards more recent insights developed within mathematics education. Synergies are drawn between…
Mathematics. [SITE 2001 Section].
ERIC Educational Resources Information Center
Connell, Michael L., Ed.; Lowery, Norene Vail, Ed.; Harnisch, Delwyn L., Ed.
This document contains the following papers on mathematics from the SITE (Society for Information Technology & Teacher Education) 2001 conference: "Secondary Mathematics Methods Course with Technology Units: Encouraging Pre-Service Teachers To Use Technology" (Rajee Amarasinghe); "Competency Exams in College Mathematics"…
ERIC Educational Resources Information Center
Buchman, Aaron; Zimmerman, Robert
This outline for Eleventh Year Mathematics in New York adheres closely to the recommendations of The Commission of Mathematics of the College Entrance Examination Board and thus presents a unified development of certain aspects of algebra, trigonometry, and analytic geometry. Its aim is both as a terminal course in mathematics and as a solid…
Mathematics and Language Experience.
ERIC Educational Resources Information Center
McGhee, Joyce
1995-01-01
Presents an approach to geometry that integrates mathematics and language teaching. Suggests that mathematics is more than manipulation of numbers: it is a way of thinking about things. Argues that mathematics and language should be united especially to achieve the goal of promoting the development of analytical thinkers, as the ability to see…
Applied Vocational Mathematics.
ERIC Educational Resources Information Center
South Carolina State Dept. of Education, Columbia. Office of Vocational Education.
Developed for use in teaching a two-semester, one-unit course, this course guide is intended to aid the high school instructor in teaching mathematical problem-solving and computational skills to vocational education students. The state-adopted textbook for general mathematics III, "Applied General Mathematics" serves as the major…
Students' Mathematical Noticing
ERIC Educational Resources Information Center
Lobato, Joanne; Hohensee, Charles; Rhodehamel, Bohdan
2013-01-01
Even in simple mathematical situations, there is an array of different mathematical features that students can attend to or notice. What students notice mathematically has consequences for their subsequent reasoning. By adapting work from both cognitive science and applied linguistics anthropology, we present a focusing framework, which treats…
Teaching for Learning Mathematics
ERIC Educational Resources Information Center
Sutherland, Ros
2006-01-01
This book explores the factors that influence young people's learning of mathematics. It uses a holistic, socio-culturally informed approach to show how all young people can be encouraged to engage with and learn mathematics. Rich examples from classroom practice are used to connect theory and practice. The role of mathematical tools, including…
ERIC Educational Resources Information Center
Darlington, Ellie
2014-01-01
This article describes part of a study which investigated the role of questions in students' approaches to learning mathematics at the secondary-tertiary interface, focussing on the enculturation of students at the University of Oxford. Use of the Mathematical Assessment Task Hierarchy taxonomy revealed A-level Mathematics and Further Mathematics…
Mathenger Hunt: Mathematics Matters.
ERIC Educational Resources Information Center
Falba, Christy J.; Weiss, Maria J.
1991-01-01
Presented is an activity which shows how mathematics is used in real life and helps to establish a need for mathematics in students' futures. Adapted from a scavenger-hunt idea, this activity helps students to discover that almost every career makes use of mathematics. (KR)
A "Mathematics Background Check"
ERIC Educational Resources Information Center
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…
Translations toward Connected Mathematics
ERIC Educational Resources Information Center
Applebaum, Mark; Leikin, Roza
2010-01-01
The translation principle allows students to solve problems in different branches of mathematics and thus to develop connectedness in their mathematical knowledge. Successful application of the translation principle depends on the classroom mathematical norms for the development of discussions and the comparison of different solutions to one…
ERIC Educational Resources Information Center
Darlington, Ellie
2014-01-01
This article describes part of a study which investigated the role of questions in students' approaches to learning mathematics at the secondary-tertiary interface, focussing on the enculturation of students at the University of Oxford. Use of the Mathematical Assessment Task Hierarchy taxonomy revealed A-level Mathematics and Further Mathematics…
Defining Mathematical Giftedness
ERIC Educational Resources Information Center
Parish, Linda
2014-01-01
This theoretical paper outlines the process of defining "mathematical giftedness" for a present study on how primary school teaching shapes the mindsets of children who are mathematically gifted. Mathematical giftedness is not a badge of honour or some special value attributed to a child who has achieved something exceptional.…