The blind student’s interpretation of two-dimensional shapes in geometry

Science.gov (United States)

Andriyani; Budayasa, I. K.; Juniati, D.

2018-01-01

The blind student’s interpretation of two-dimensional shapes represents the blind student’s mental image of two-dimensional shapes that they can’t visualize directly, which is related to illustration of the characteristics and number of edges and angles. The objective of this research is to identify the blind student’s interpretation of two-dimensional shapes. This research was an exploratory study with qualitative approach. A subject of this research is a sixth-grade student who experiencing total blind from the fifth grade of elementary school. Researchers interviewed the subject about his interpretation of two-dimensional shapes according to his thinking.The findings of this study show the uniqueness of blind students, who have been totally blind since school age, in knowing and illustrating the characteristics of edges and angles of two-dimensional shapes by utilizing visual experiences that were previously obtained before the blind. The result can inspire teachers to design further learning for development of blind student geometry concepts.

A Textbook Argument: Definitions of Argument in Leading Composition Textbooks

Science.gov (United States)

Knoblauch, A. Abby

2011-01-01

This essay examines the definitions and practices of argument perpetuated by popular composition textbooks, illustrating how even those texts that appear to forward expansive notions of argument ultimately limit it to an intent to persuade. In doing so, they help perpetuate constricted practices of argument within undergraduate composition…

Textbook Evaluation and Selection: A Professional Responsibility.

Science.gov (United States)

Kachaturoff, Grace

1982-01-01

Discusses why teachers must help to review and/or select textbooks on a regular basis and how they can participate in this process. A slightly revised edition of the criteria used by the State of Michigan Social Studies Review Steering Committee illustrates critical factors that must be considered in evaluating textbooks. (SR)

My Daughter Wants to Be a Nurse: Occupational Stereotyping in Health Textbooks.

Science.gov (United States)

Holcomb, Carol Ann

1981-01-01

An evaluation of the illustrations in elementary and secondary education textbooks reveals that: (1) Males dominate occupations illustrated in contemporary health textbooks; and (2) females are generally portrayed as assistants (nurses, technicians, dental hygienists) to males in higher-level roles or in occupations with low levels of power,…

Textbook language: Incentive or obstacle

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Šefer Jasmina

2008-01-01

Full Text Available The criticism of the current language in school textbooks indicates the gravity of this problem in our environment and the need to solve it. The first step in approaching this problem is studying the reception of primary school textbooks. In the first part of the paper we discuss all primary school textbooks from the fifth to the eighth grade with regard to the frequency of textbook usage and the perception of the difficulty of textbook language. In the second part of the paper there is an additional analysis of history, geography, biology, physics and chemistry textbooks from the fifth to the eighth grade with regard to the reasons for which pupils find them difficult. This preliminary research comprised in total 120 pupils from an urban school, thirty from each fifth to eighth grade. We analyzed the textbooks of the Institute for Textbook Publishing and Teaching Aids, which are used most frequently in our educational practice, and hence can represent the general situation of the problem. Bearing in mind the limited size of the sample of pupils, the results are used only as an illustration and should encourage new studies on a more extensive sample. Textbook language is often difficult since it is mostly insufficiently comprehensible, longwinded and with many data. In natural sciences, physics and chemistry, pupils give up studying from the textbook. The textbooks in narrative subjects lead the way with respect to their usage, among which everybody finds history textbooks most difficult. Geography and biology textbooks were evaluated differently, depending on the grade and success of the pupils declaring themselves. The results present a guideline to the current and new writers of our textbooks, critics and publishing houses.

EVALUATING GENDER-BIAS IN THE IRANIAN PRE-UNIVERSITY ENGLISH TEXTBOOKS

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Ali Roohani

2013-07-01

Full Text Available Abstract: Textbooks can affect learners’ attitudes, viewpoints, and their choice of language in second/foreign language (L2 communication. The various ways in which the people are displayed in communication may affect students’ viewpoints. This study was an attempt to examine several potential areas of gender-bias in the representation of women and men in the pre-university English textbook, an English language teaching (ELT textbook with two volumes taught in the high schools of Iran. To evaluate this textbook, content analysis was done in terms of gender-bias, gender-neutral, male-generics, and the firstness in the reading texts, instructions, exercises and illustrations. The frequency and percentages of names, nouns, pronouns and pictures attributed to each gender (i.e., males and females were obtained and chi-square tests were carried out. In general, names, nouns and pictures pertinent to males outnumbered those attributed to females. Besides, there was a statistically significant difference between males and females in the two volumes of the pre-university textbook in terms of the above features. Also, male-oriented terms came first more frequently. However, there was not a statistically significant difference between male and female pronouns between the two volumes, though the percentage of male pronouns was higher. Moreover, the textbook included many gender-neutral nouns and pronouns not having any gender orientations. Findings indicated that the Iranian pre-university English textbook was somehow male-oriented and gender-biased as regards names, nouns, firstness and pictures associated with them though great efforts were made to avoid specific gender orientations.

One-dimensional versus two-dimensional electronic states in vicinal surfaces

International Nuclear Information System (INIS)

Ortega, J E; Ruiz-Oses, M; Cordon, J; Mugarza, A; Kuntze, J; Schiller, F

2005-01-01

Vicinal surfaces with periodic arrays of steps are among the simplest lateral nanostructures. In particular, noble metal surfaces vicinal to the (1 1 1) plane are excellent test systems to explore the basic electronic properties in one-dimensional superlattices by means of angular photoemission. These surfaces are characterized by strong emissions from free-electron-like surface states that scatter at step edges. Thereby, the two-dimensional surface state displays superlattice band folding and, depending on the step lattice constant d, it splits into one-dimensional quantum well levels. Here we use high-resolution, angle-resolved photoemission to analyse surface states in a variety of samples, in trying to illustrate the changes in surface state bands as a function of d

Stability of two-dimensional vorticity filaments

International Nuclear Information System (INIS)

Elhmaidi, D.; Provenzale, A.; Lili, T.; Babiano, A.

2004-01-01

We discuss the results of a numerical study on the stability of two-dimensional vorticity filaments around a circular vortex. We illustrate how the stability of the filaments depends on the balance between the strain associated with the far field of the vortex and the local vorticity of the filament, and we discuss an empirical criterion for filament stability

Dimensional analysis for engineers

CERN Document Server

Simon, Volker; Gomaa, Hassan

2017-01-01

This monograph provides the fundamentals of dimensional analysis and illustrates the method by numerous examples for a wide spectrum of applications in engineering. The book covers thoroughly the fundamental definitions and the Buckingham theorem, as well as the choice of the system of basic units. The authors also include a presentation of model theory and similarity solutions. The target audience primarily comprises researchers and practitioners but the book may also be suitable as a textbook at university level.

Textbook Factor Demand Curves.

Science.gov (United States)

Davis, Joe C.

1994-01-01

Maintains that teachers and textbook graphics follow the same basic pattern in illustrating changes in demand curves when product prices increase. Asserts that the use of computer graphics will enable teachers to be more precise in their graphic presentation of price elasticity. (CFR)

Approximate solutions for the two-dimensional integral transport equation. Solution of complex two-dimensional transport problems

International Nuclear Information System (INIS)

Sanchez, Richard.

1980-11-01

This work is divided into two parts: the first part deals with the solution of complex two-dimensional transport problems, the second one (note CEA-N-2166) treats the critically mixed methods of resolution. A set of approximate solutions for the isotropic two-dimensional neutron transport problem has been developed using the interface current formalism. The method has been applied to regular lattices of rectangular cells containing a fuel pin, cladding, and water, or homogenized structural material. The cells are divided into zones that are homogeneous. A zone-wise flux expansion is used to formulate a direct collision probability problem within a cell. The coupling of the cells is effected by making extra assumptions on the currents entering and leaving the interfaces. Two codes have been written: CALLIOPE uses a cylindrical cell model and one or three terms for the flux expansion, and NAUSICAA uses a two-dimensional flux representation and does a truly two-dimensional calculation inside each cell. In both codes, one or three terms can be used to make a space-independent expansion of the angular fluxes entering and leaving each side of the cell. The accuracies and computing times achieved with the different approximations are illustrated by numerical studies on two benchmark problems and by calculations performed in the APOLLO multigroup code [fr

Three dimensional illustrating - three-dimensional vision and deception of sensibility

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Anita Gánóczy

2009-03-01

Full Text Available The wide-spread digital photography and computer use gave the opportunity for everyone to make three-dimensional pictures and to make them public. The new opportunities with three-dimensional techniques give chance for the birth of new artistic photographs. We present in detail the biological roots of three-dimensional visualization, the phenomena of movement parallax, which can be used efficiently in making three-dimensional graphics, the Zöllner- and Corridor-illusion. There are present in this paper the visual elements, which contribute to define a plane two-dimensional image in three-dimension: coherent lines, the covering, the measurement changes, the relative altitude state, the abatement of detail profusion, the shadings and the perspective effects of colors.

The Prospect and Challenge of Textbook Research in English Language Education

OpenAIRE

王, 林鋒

2014-01-01

This paper respectively illustrates the development of generic textbook research and English language textbook research. The review of generic textbook research starts with the establishment of the field, then moves to the emergence of New Sociology of Education, and finally describes its research methodology as well. The development of English language textbook research is traced back to teaching material development in English-speaking countries. Following that, a survey of English language...

Technology and Textbooks: The Future

Science.gov (United States)

Baglione, Stephen L.; Sullivan, Kevin

2016-01-01

This article describes two separate studies: a survey of students' textbook perceptions, purchases, and usage for e-textbooks and print textbooks and a conjoint analysis on e-textbook attributes. Print textbooks were perceived as easier to read, understand, and navigate, whereas e-textbooks were perceived to be cheaper. Students were willing to…

Two- and three-dimensional evaluation of the acetabulum in the pediatric patient

International Nuclear Information System (INIS)

Magid, D.; Fishman, E.K.; Sponseller, P.D.

1987-01-01

Complex anatomic structures such as the hip and acetabulum are best evaluated with the use of two- and three-dimensional reconstruction techniques and standard transaxial CT data. CT scans of children with various hip pathologies, including congenital hip dislocation, slipped capital femoral epiphyses, hip dysplasias, dwarfism, and acetabular fractures, were reviewed to determine the value of two- and three-dimensional imaging. The advantages of two-dimensional imaging techniques (sequential coronal/sagittal reconstruction) and three-dimensional valumetric imaging techniques (using real-time video display) are illustrated with specific examples

Confined catalysis under two-dimensional materials

OpenAIRE

Li, Haobo; Xiao, Jianping; Fu, Qiang; Bao, Xinhe

2017-01-01

Small spaces in nanoreactors may have big implications in chemistry, because the chemical nature of molecules and reactions within the nanospaces can be changed significantly due to the nanoconfinement effect. Two-dimensional (2D) nanoreactor formed under 2D materials can provide a well-defined model system to explore the confined catalysis. We demonstrate a general tendency for weakened surface adsorption under the confinement of graphene overlayer, illustrating the feasible modulation of su...

What Do Language Teachers Think about Interchange and American English File? Teacher’s Evaluation of Two ESL Textbooks in Iran

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Hassan Soleimani

2013-09-01

Full Text Available Materials evaluation is a critically significant feature of a coherent curriculum to achieve the objectives of pedagogy. To this end, two EFL textbooks commonly taught in language institutes in Iran, namely Interchange series and American English File, were selected for evaluation, seeking teachers’ viewpoints on the effectiveness of the two textbooks. Thirty EFL teachers who had used these two textbooks in their teaching experience participated in the study. A modified version of Litz’s (2005 teacher textbook evaluation form was used to collect data. Analysis of the collected data showed that the teachers were satisfied with the two materials. Moreover, it was found that the difference between the two textbooks was not significant in four features including practical considerations, layout and design, activities, and skills but this difference was significant in two features including language type as well as subject and content. The authors of the two textbooks, the administrators of language institutes, curriculum and material developers, and also students interested in learning EFL can benefit from the findings of this study.

Understanding the Influence of Two Mathematics Textbooks on Prospective Secondary Teachers' Knowledge

Science.gov (United States)

Davis, Jon D.

2009-01-01

This study examines the influence of reading and planning from two differently organized mathematics textbooks on prospective high school mathematics teachers' pedagogical content knowledge and content knowledge of exponential functions. The teachers completed a pretest and two posttests. On the pretest, the teachers possessed an incomplete…

A Practical and Complementary Approach to the Evaluation of ESL Composition Textbooks.

Science.gov (United States)

Olivares-Cuhat, Gabriela

2002-01-01

Outlines a method for evaluating the strategy training component in composition textbooks designed for English-as-a-Second-Language and other second and foreign language students. The procedure--a checklist--is described and illustrated through the analysis of three sample chapters from three college level writing textbooks. (Author/VWL)

Physics with illustrative examples from medicine and biology

CERN Document Server

Benedek, George B

Physics: with illustrative examples from medicine and biology is a three-volume set of textbooks in introductory physics written at the calculus level and designed primarily for students with career objectives in the life sciences.

The Content Analysis, Material Presentation, and Readability of Curriculum 2013 Science Textbook for 1st Semester of Junior High School 7th Grade

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Endik Deni Nugroho

2017-07-01

Full Text Available Based on the early observation by researchers of the two Science textbooks 7thGrade about biological material, 1stand 2ndsemester of curriculum 2013, there were errors in the material presentation and legibility. This study aimed to compare and find the contents suitability of the book based on standard of competence and basic competences, readability, materials presentation and supporting material in the science textbook VII grade, 1st and 2nd semester and measured student legibility. This study used a qualitative descriptive approach by using document analysis. The data resources were obtained by using purposive, the data collection was triangulation, data analysis was inductive/qualitative and the results emphasized the meaning. This research results showed that the Integrated Sciences and Sciences textbook 1st and 2nd semester meet the standards of the core competencies and basic competence on the syllabus curriculum 2013 and also meet the books standart. The results of the analysis conducted in misstatement concept and principles and material llustration in the Integrated Science textbook 1st semester were found 5 misstatement concept, for the presentation of the principles and material illustration was found no error. In the book Integrated Sciences there was no delivery errors concept, principle, and material illustration. Science textbook 1st semester found 8 concepts misstatements and 8 illustration material misstatements. In general, Integrated Sciences and Sciences textbooks 1st and 2nd semester are illegibility so not appropriate for students.

Textbooks evaluation

OpenAIRE

Tauchmannová, Iva

2009-01-01

This thesis deals with an evaluation of textbooks and their operation at school. The theoretical part clarifies the purport of the term a textbook, functions and a structure of textbooks, and describes a text of textbooks, parameters of its evaluation, and the extratextual components of textbooks. It presents methods of work with a textbook and research into textbooks. The empirical part describes a research that was aimed to learn whether textbooks fit to modern parameters of textbooks. Furt...

Evaluating Junior Secondary Science Textbook Usage in Australian Schools

Science.gov (United States)

McDonald, Christine V.

2016-08-01

A large body of research has drawn attention to the importance of providing engaging learning experiences in junior secondary science classes, in an attempt to attract more students into post-compulsory science courses. The reality of time and resource constraints, and the high proportion of non-specialist science teachers teaching science, has resulted in an overreliance on more transmissive pedagogical tools, such as textbooks. This study sought to evaluate the usage of junior secondary science textbooks in Australian schools. Data were collected via surveys from 486 schools teaching junior secondary (years 7-10), representing all Australian states and territories. Results indicated that most Australian schools use a science textbook in the junior secondary years, and textbooks are used in the majority of science lessons. The most highly cited reason influencing choice of textbook was layout/colour/illustrations, and electronic technologies were found to be the dominant curricula material utilised, in addition to textbooks, in junior secondary science classes. Interestingly, the majority of respondents expressed high levels of satisfaction with their textbooks, although many were keen to stress the subsidiary role of textbooks in the classroom, emphasising the textbook was `one' component of their teaching repertoire. Importantly, respondents were also keen to stress the benefits of textbooks in supporting substitute teachers, beginning teachers, and non-specialist science teachers; in addition to facilitating continuity of programming and staff support in schools with high staff turnover. Implications from this study highlight the need for high quality textbooks to support teaching and learning in Australian junior secondary science classes.

Two-dimensional and three-dimensional models used for teaching Human Evolution in Secondary Schools. Learning proficiency assessment. A Case Study

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Ulisses Dardon

2016-06-01

Full Text Available The evolution of the human species is a topic of extreme importance reported in the “Parâmetros Curriculares Nacionais do Ensino Médio – PCNEM” (National Curriculum Standards of Secondary Education, although it is not often taught as part of basic education. This work presents the results of an experimental work performed with 31 students of a religious high school of State of Rio de Janeiro. Learning proficiency was assessed by using two-dimensional (2D and three-dimensional (3D illustration techniques of hominids skulls and a Pongidae for teaching Human Evolution. The teaching-learning process using these methodologies was more effective with the application of three-dimensional (3D illustration techniques. The group of students that used 3D illustrations were able to observe similarities and differences between the presented taxonomic models, and formulate hypotheses about their palaeobiology more consistently than the students that used 2D models. Results of this work indicate that the use of three-dimensional techniques (3D provides an excellent support to teaching-learning process in basic education, captivating and stimulating new interests of students during the educational process.

The Slovenian Art History Textbook in Comparison to Polish Textbooks: Authorship and Content, Didactic Structure and Publishing Circumstances

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Marjana Dolšina

2014-09-01

Full Text Available The paper analyses two concepts of art history textbooks for secondary schools. It discusses their role in the learning and teaching process of art history and related school subjects within the formal educational programmes in Slovenia and their didactic structure. The comparison between one Slovenian and two Polish textbooks might contribute to better understanding of the present situation regarding art history textbook production in Slovenia, which is a result of several factors: the historical continuity of textbook writing and research in textbook didactics, the current school policy and financial competition on the textbook market. Its intention is also to clarify the idea of didactic transformation of the art history contents from the challenging scientific texts to a form suitable for secondary school students who are textbooks' main target audience.

Journey to Textbook Affordability: An Investigation of Students’ Use of eTextbooks at Multiple Campuses

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Eun-Ok Baek

2013-07-01

Full Text Available eTextbooks have steadily and recently more rapidly penetrated the textbook market. In order to effectively support students’ learning, it is important to comprehend students’ experiences using eTextbooks. This survey study was designed to gain an understanding of students’ experiences in using eTextbooks and variables that impact their experiences, perceptions, and attitudes towards eTextbooks. In a total of 33 courses, faculty members at five state university campuses in California participated in the eTextbook pilot project during the fall of 2010. Six hundred and sixty-two student questionnaires were returned from those courses. Key findings include: 1 More than one-third of the students were satisfied with the eTextbook; 2 more than half of the students felt that the eTextbook was easy-to-use; 3 older students (22 or older tended to have more positive experiences with the eTextbook than younger students; and 4 students most liked the eTextbook’s cost, accessibility, light weight, and keyword search features. This study implies that the eTextbook must be a high-quality, easy-to-use resource to serve as a viable textbook option for student learning.

An educationally inspired illustration of two-dimensional Quantitative Microbiological Risk Assessment (QMRA) and sensitivity analysis.

Science.gov (United States)

Vásquez, G A; Busschaert, P; Haberbeck, L U; Uyttendaele, M; Geeraerd, A H

2014-11-03

Quantitative Microbiological Risk Assessment (QMRA) is a structured methodology used to assess the risk involved by ingestion of a pathogen. It applies mathematical models combined with an accurate exploitation of data sets, represented by distributions and - in the case of two-dimensional Monte Carlo simulations - their hyperparameters. This research aims to highlight background information, assumptions and truncations of a two-dimensional QMRA and advanced sensitivity analysis. We believe that such a detailed listing is not always clearly presented in actual risk assessment studies, while it is essential to ensure reliable and realistic simulations and interpretations. As a case-study, we are considering the occurrence of listeriosis in smoked fish products in Belgium during the period 2008-2009, using two-dimensional Monte Carlo and two sensitivity analysis methods (Spearman correlation and Sobol sensitivity indices) to estimate the most relevant factors of the final risk estimate. A risk estimate of 0.018% per consumption of contaminated smoked fish by an immunocompromised person was obtained. The final estimate of listeriosis cases (23) is within the actual reported result obtained for the same period and for the same population. Variability on the final risk estimate is determined by the variability regarding (i) consumer refrigerator temperatures, (ii) the reference growth rate of L. monocytogenes, (iii) the minimum growth temperature of L. monocytogenes and (iv) consumer portion size. Variability regarding the initial contamination level of L. monocytogenes tends to appear as a determinant of risk variability only when the minimum growth temperature is not included in the sensitivity analysis; when it is included the impact regarding the variability on the initial contamination level of L. monocytogenes is disappearing. Uncertainty determinants of the final risk indicated the need of gathering more information on the reference growth rate and the minimum

Developing Textbook Materials in Uncommon Languages.

Science.gov (United States)

Lathrop, Thomas A.

Guidelines are offered for preparing and publishing textbook materials in Portuguese and other uncommonly taught languages. The available options for publishing Portuguese materials include two textbook publishers, three university presses, self-publication, and the Cabrilho Press, which produces language textbooks. Methods for submitting…

In the Middle of Nowhere: How a Textbook Can Position the Mathematics Learner

Science.gov (United States)

Herbel-Eisenmann, Beth; Wagner, David

2005-01-01

We outline a framework for investigating how a mathematics textbook positions the mathematics learner. We use tools and concepts from discourse analysis, a field of linguistic scholarship, to illustrate the ways in which a textbook can position people in relation to mathematics and how the text can position the mathematics learner in relation to…

Two dimensional solid state NMR

International Nuclear Information System (INIS)

Kentgens, A.P.M.

1987-01-01

This thesis illustrates, by discussing some existing and newly developed 2D solid state experiments, that two-dimensional NMR of solids is a useful and important extension of NMR techniques. Chapter 1 gives an overview of spin interactions and averaging techniques important in solid state NMR. As 2D NMR is already an established technique in solutions, only the basics of two dimensional NMR are presented in chapter 2, with an emphasis on the aspects important for solid spectra. The following chapters discuss the theoretical background and applications of specific 2D solid state experiments. An application of 2D-J resolved NMR, analogous to J-resolved spectroscopy in solutions, to natural rubber is given in chapter 3. In chapter 4 the anisotropic chemical shift is mapped out against the heteronuclear dipolar interaction to obtain information about the orientation of the shielding tensor in poly-(oxymethylene). Chapter 5 concentrates on the study of super-slow molecular motions in polymers using a variant of the 2D exchange experiment developed by us. Finally chapter 6 discusses a new experiment, 2D nutation NMR, which makes it possible to study the quadrupole interaction of half-integer spins. 230 refs.; 48 figs.; 8 tabs

A pedagogical analysis of science textbooks: How can we proceed?

Science.gov (United States)

Koulaidis, Vasilis; Tsatsaroni, Anna

1996-03-01

This paper discusses some of the available frameworks for the pedagogical analysis of school science textbooks. First, it distinguishes between (a) studies which focus on elements of textbooks, such as the content, vocabulary, illustrations used, and the teaching methods promoted; and (b) those which consider the principles that organize the content and the form of presentation. In attempting to consider the sorts of principles that may be used in the studies categorised under (b), two crucial issues are discussed. The first issue refers to the relationship between scientific knowledge and school knowledge, which, as the relevant literature suggests, might not be conceived merely as a simplified “casting” of the scientific structure, but rather should be understood as a complex social process. The second issue explicitly addresses the nature of the pedagogic relationship and the place of the pedagogic text within it. Recent views about the nature of knowledge, it is argued, would suggest a reconceptualisation of the teaching activity, and indicate a model according to which the three elements of the teaching situation-the content, the pupil and the teacher—are seen as being (re)constituted in their articulation within and through the text(book). Thus, for example, what is to be a competent pupil in this approach is a function of the text. On the basis of these considerations, three approaches to the analysis of science textbooks are discussed: the socio-cognitive, the sociolinguistic and the socio-epistemic. The relative merits of the third approach are considered, and some examples are used from Greek science textbooks.

An Investigation into the Use of Cohesive Devises in Iranian High School EFL Textbooks

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Mansour Shabani

2015-07-01

Full Text Available The present study aimed at probing into the use of grammatical and lexical cohesive subdevices in Iranian high school EFL textbooks. To this end, the reading sections of three high school EFL textbooks and one pre-university EFL textbook were analyzed in terms of the distribution of grammatical and lexical cohesive subdevices. The results of One-way ANOVA illustrated that: athere are no significant differences among the frequencies of grammatical cohesive subdevices across grade 1 high school EFL textbook and the pre-university EFL textbook, bthere are significant differences among the frequencies of grammatical cohesive subdevices across grades 2 and 3 high school EFL textbooks. Moreover, the results of Chi-Square test showed that the significant values of all of the lexical cohesive subdevices were higher than .05 across each of the Iranian EFL high school textbooks. These findings can be beneficial for textbook writers, materials developers and EFL teachers.

Management Textbooks as Propaganda.

Science.gov (United States)

Cameron, Kim S.; Ireland, R. Duane; Lussier, Robert N.; New, J. Randolph; Robbins, Stephen P.

2003-01-01

Four management textbook authors react to the metaphor of textbooks as propaganda. All write to support managerial ideology and are aware of the market, but believe their role in shaping the field is limited. Includes two responses: "Propaganda, Trusteeship, and Artifact" (Daniel R. Gilbert) and "The Hegemonic Discourse of…

Two-dimensional errors

International Nuclear Information System (INIS)

Anon.

1991-01-01

This chapter addresses the extension of previous work in one-dimensional (linear) error theory to two-dimensional error analysis. The topics of the chapter include the definition of two-dimensional error, the probability ellipse, the probability circle, elliptical (circular) error evaluation, the application to position accuracy, and the use of control systems (points) in measurements

"World Religions" in Introductory Sociology Textbooks

Science.gov (United States)

Carroll, Michael P.

2017-01-01

A section on "world religions" (WRs) is now routinely included in the religion chapters of introductory sociology textbooks. Looking carefully at these WR sections, however, two things seem puzzling. The first is that the criteria for defining a WR varies considerably from textbook to textbook; the second is that these WRs sections…

[The Prague school of anatomy and its illustrators].

Science.gov (United States)

Linc, R

1997-01-01

The centennial commemorial of the birthday of Ladislav Borovanský gives us an incentive for describing a short history of Czech anatomy in Medical Faculty of Charles University with their textbooks and painters. Parallelly with them are presented some other distinguished painters active in anatomical aspect of illustration.

Introductory Level Problems Illustrating Concepts in Pharmaceutical Engineering

Science.gov (United States)

McIver, Keith; Whitaker, Kathryn; De Delva, Vladimir; Farrell, Stephanie; Savelski, Mariano J.; Slater, C. Stewart

2012-01-01

Textbook style problems including detailed solutions introducing pharmaceutical topics at the level of an introductory chemical engineering course have been created. The problems illustrate and teach subjects which students would learn if they were to pursue a career in pharmaceutical engineering, including the unique terminology of the field,…

Introductory Biology Textbooks Under-Represent Scientific Process

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Dara B. Duncan

2011-08-01

Full Text Available Attrition of undergraduates from Biology majors is a long-standing problem. Introductory courses that fail to engage students or spark their curiosity by emphasizing the open-ended and creative nature of biological investigation and discovery could contribute to student detachment from the field. Our hypothesis was that introductory biology books devote relatively few figures to illustration of the design and interpretation of experiments or field studies, thereby de-emphasizing the scientific process.To investigate this possibility, we examined figures in six Introductory Biology textbooks published in 2008. On average, multistep scientific investigations were presented in fewer than 5% of the hundreds of figures in each book. Devoting such a small percentage of figures to the processes by which discoveries are made discourages an emphasis on scientific thinking. We suggest that by increasing significantly the illustration of scientific investigations, textbooks could support undergraduates’ early interest in biology, stimulate the development of design and analytical skills, and inspire some students to participate in investigations of their own.

Kinetics of two-dimensional electron plasma, interacting with fluctuating potential

International Nuclear Information System (INIS)

Boiko, I.I.; Sirenko, Y.M.

1990-01-01

In this paper, from the first principles, after the fashion of Klimontovich, the authors derive quantum kinetic equation for electron gas, inhomogeneous in z-direction and homogeneous in XY-plane. Special attention is given to the systems with quasi-two-dimensional electron gas (2 DEG), which are widely explored now. Both interaction between the particles of 2 DEG (in general, of several sorts), and interaction with an external system (phonons, impurities, after change carries etc.) are considered. General theory is used to obtain energy and momentum balance equations and relaxation frequencies for 2 DEG in the basis of plane waves. The case of crossed electric and magnetic fields is also treated. As an illustration the problems of 2 DEG scattering on semibounded three-dimensional electron gas and on two-dimensional hole gas are considered; transverse conductivity of nondegenerate 2 DEG, scattered by impurities in ultraquantum magnetic field, is calculated

ONE-DIMENSIONAL AND TWO-DIMENSIONAL LEADERSHIP STYLES

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Nikola Stefanović

2007-06-01

Full Text Available In order to motivate their group members to perform certain tasks, leaders use different leadership styles. These styles are based on leaders' backgrounds, knowledge, values, experiences, and expectations. The one-dimensional styles, used by many world leaders, are autocratic and democratic styles. These styles lie on the two opposite sides of the leadership spectrum. In order to precisely define the leadership styles on the spectrum between the autocratic leadership style and the democratic leadership style, leadership theory researchers use two dimensional matrices. The two-dimensional matrices define leadership styles on the basis of different parameters. By using these parameters, one can identify two-dimensional styles.

Medical Subspecialty Textbooks in the 21st Century. Essential or Headed for Extinction?

Science.gov (United States)

Broaddus, V Courtney; Grippi, Michael A

2015-08-01

In recent years, the role of medical subspecialty textbooks as sources of information for students, trainees, and practicing clinicians has been challenged. Although the structure of textbooks continues to evolve from standard, printed versions to digital formats, including e-books and online texts, we maintain that the authoritative compilation of clinical and scientific material by experts in the field (i.e., a modern-day textbook) remains central to the education, training, and practice of subspecialists. Regardless of format, an effective medical subspecialty textbook is authoritative, comprehensive, and integrated in its coverage of the subject. Textbook content represents a unique synthesis of clinical and scientific material of real educational and clinical value. Incorporation of illustrations, including figures, tables, videos, and audios, bolsters the presentation and further solidifies the reader's understanding of the subject. The textbook, both printed and digital, reinforces the many widely available online resources and serves as a platform from which to evaluate other sources of information and to launch additional scientific and clinical inquiry.

Naïve conceptions about multimedia learning: a study on primary school textbooks

OpenAIRE

Colombo, Barbara; Antonietti, Alessandro

2013-01-01

HIGHLIGHTS This interview study explores beliefs about the instructional role of illustrations We compared illustrators', teachers', students' and common people's ideas Participants' responses were internally coherent and close to multimedia learning theory We propose and discuss an integrated multimedia learning model An interview study, based on specific pictures taken from textbooks used in primary schools, was carried out to investigate illustrators', teachers', students'...

Geometric Transformations in Middle School Mathematics Textbooks

Science.gov (United States)

Zorin, Barbara

2011-01-01

This study analyzed treatment of geometric transformations in presently available middle grades (6, 7, 8) student mathematics textbooks. Fourteen textbooks from four widely used textbook series were evaluated: two mainline publisher series, Pearson (Prentice Hall) and Glencoe (Math Connects); one National Science Foundation (NSF) funded curriculum…

The impact of role reversal in representational practices in history textbooks after Apartheid

Directory of Open Access Journals (Sweden)

Alta Engelbrecht

2008-11-01

Full Text Available History became a mere sub-section in the broad category of social sciences in the (then new Curriculum 2005, significantly diluting it as a school subject. Yet the rewriting of South African history textbooks after the seminal democratic elections in South Africa during 1994 became a tool to counter the Apartheid stereotypes, previously loaded with strong cultural and political content. The focus during the past 10-12 years in South African historiography, on the reversal of the colonial portrayal of Africans, has resulted in the de-mystification of Eurocentrism in textbooks. New myths and new silences were re-instated and ensured that again only one voice is dominant - the voice of black South Africans. Multi-perspectivity, one of the non-negotiable pillars of post-modern historiography, is being disregarded in a country attempting to write a sound report of its past. In this article I address the extent to which white and black role reversal is reflected in representational practices in current South African historiography perspectives. A research group of six academics examined the illustrative material of nine series Grades 4-6 primary school history textbooks to identify the extent of racial representation. Both quantitative and qualitative analyses were conducted. Of all the illustrations in the textbooks, 15% depicted whites, 50% blacks, and 35% blacks and whites together. The qualitative findings suggest that so-called 'white history' is marginalized in the exemplars. White role models are downplayed and portrayed only as peripheral figures, making their race indistinct. The "butterscotch-effect" (the light colouring of faces contributes to the fact that there are no racially marked identities. Learners will therefore have difficulty in identifying with the characters and narrators, especially since attempts to portray multi-perspectivity were found in only two textbooks. The data suggest that Afrikaner nationalist views are being

Designing a Tool for History Textbook Analysis

Directory of Open Access Journals (Sweden)

Katalin Eszter Morgan

2012-11-01

Full Text Available This article describes the process by which a five-dimensional tool for history textbook analysis was conceptualized and developed in three stages. The first stage consisted of a grounded theory approach to code the content of the sampled chapters of the books inductively. After that the findings from this coding process were combined with principles of text analysis as derived from the literature, specifically focusing on the notion of semiotic mediation as theorized by Lev VYGOTSKY. We explain how we then entered the third stage of the development of the tool, comprising five dimensions. Towards the end of the article we show how the tool could be adapted to serve other disciplines as well. The argument we forward in the article is for systematic and well theorized tools with which to investigate textbooks as semiotic mediators in education. By implication, textbook authors can also use these as guidelines. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs130170

Two-dimensional NMR spectrometry

International Nuclear Information System (INIS)

Farrar, T.C.

1987-01-01

This article is the second in a two-part series. In part one (ANALYTICAL CHEMISTRY, May 15) the authors discussed one-dimensional nuclear magnetic resonance (NMR) spectra and some relatively advanced nuclear spin gymnastics experiments that provide a capability for selective sensitivity enhancements. In this article and overview and some applications of two-dimensional NMR experiments are presented. These powerful experiments are important complements to the one-dimensional experiments. As in the more sophisticated one-dimensional experiments, the two-dimensional experiments involve three distinct time periods: a preparation period, t 0 ; an evolution period, t 1 ; and a detection period, t 2

Type Synthesis of Parallel Mechanisms with the First Class GF Sets and Two-Dimensional Rotations

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Jialun Yang

2012-09-01

Full Text Available The novel design of parallel mechanisms plays a key role in the potential application of parallel mechanisms. In this paper, the type synthesis of parallel mechanisms with the first class GF sets and two-dimensional rotations is studied. The rule of two-dimensional rotations is given, which lays the theoretical foundation for the intersection operations of specific GF sets. Next, kinematic limbs with specific characteristics are designed according to the 2-D and 3-D axes movement theorems. Finally, several synthesized parallel mechanisms with the first class GF sets and two-dimensional rotations are illustrated to show the effectiveness of the proposed methodology.

Emergency Victim Care. A Textbook for Emergency Medical Personnel.

Science.gov (United States)

Ohio State Dept. of Education, Columbus. Trade and Industrial Education Service.

This textbook for emergency medical personnel should be useful to fire departments, private ambulance companies, industrial emergency and rescue units, police departments, and nurses. The 30 illustrated chapters cover topics such as: (1) Emergency Medical Service Vehicles, (2) Safe Driving Practices, (3) Anatomy and Physiology, (4) Closed Chest…

The Council of Europe's Citizenship Conception in "Education for Democratic Citizenship": A Critical Discourse Analysis of Two Textbooks

Science.gov (United States)

Ververi, Olga

2017-01-01

This paper presents a neocommunitarian conception of citizenship identified in two textbooks of the programme "Education for Democratic Citizenship," organised by the Council of Europe. Critical discourse analysis is applied to the key themes of the textbooks "T-Kit 7: Under construction: Citizenship Youth and Europe" and…

Discriminating image textures with the multiscale two-dimensional complexity-entropy causality plane

International Nuclear Information System (INIS)

Zunino, Luciano; Ribeiro, Haroldo V.

2016-01-01

The aim of this paper is to further explore the usefulness of the two-dimensional complexity-entropy causality plane as a texture image descriptor. A multiscale generalization is introduced in order to distinguish between different roughness features of images at small and large spatial scales. Numerically generated two-dimensional structures are initially considered for illustrating basic concepts in a controlled framework. Then, more realistic situations are studied. Obtained results allow us to confirm that intrinsic spatial correlations of images are successfully unveiled by implementing this multiscale symbolic information-theory approach. Consequently, we conclude that the proposed representation space is a versatile and practical tool for identifying, characterizing and discriminating image textures.

Periodic trajectories for two-dimensional nonintegrable Hamiltonians

International Nuclear Information System (INIS)

Davies, K.T.R.

1990-02-01

I want to report on some calculations of classical periodic trajectories in a two-dimensional nonintegrable potential. After a brief introduction, I will present some details of the theory. The main part of this report will be devoted to showing pictures of the various families of trajectories and to discussing the topology (in E-τ space) and branching behavior of these families. Then I will demonstrate the connection between periodic trajectories and ''nearby'' nonperiodic trajectories, which nicely illustrates the relationship of this work to chaos. Finally, I will discuss very briefly how periodic trajectories can be used to calculate tori. 12 refs., 40 figs

One-Dimensional Finite Elements An Introduction to the FE Method

CERN Document Server

Öchsner, Andreas

2013-01-01

 This textbook presents finite element methods using exclusively  one-dimensional elements. The aim is to present the complex methodology in  an easily understandable but mathematically correct fashion. The approach of  one-dimensional elements enables the reader to focus on the understanding of  the principles of basic and advanced mechanical problems. The reader easily  understands the assumptions and limitations of mechanical modeling as well  as the underlying physics without struggling with complex mathematics. But  although the description is easy it remains scientifically correct.   The approach using only one-dimensional elements covers not only standard  problems but allows also for advanced topics like plasticity or the  mechanics of composite materials. Many examples illustrate the concepts and  problems at the end of every chapter help to familiarize with the topics.

Two-dimensional PCA-based human gait identification

Science.gov (United States)

Chen, Jinyan; Wu, Rongteng

2012-11-01

It is very necessary to recognize person through visual surveillance automatically for public security reason. Human gait based identification focus on recognizing human by his walking video automatically using computer vision and image processing approaches. As a potential biometric measure, human gait identification has attracted more and more researchers. Current human gait identification methods can be divided into two categories: model-based methods and motion-based methods. In this paper a two-Dimensional Principal Component Analysis and temporal-space analysis based human gait identification method is proposed. Using background estimation and image subtraction we can get a binary images sequence from the surveillance video. By comparing the difference of two adjacent images in the gait images sequence, we can get a difference binary images sequence. Every binary difference image indicates the body moving mode during a person walking. We use the following steps to extract the temporal-space features from the difference binary images sequence: Projecting one difference image to Y axis or X axis we can get two vectors. Project every difference image in the difference binary images sequence to Y axis or X axis difference binary images sequence we can get two matrixes. These two matrixes indicate the styles of one walking. Then Two-Dimensional Principal Component Analysis(2DPCA) is used to transform these two matrixes to two vectors while at the same time keep the maximum separability. Finally the similarity of two human gait images is calculated by the Euclidean distance of the two vectors. The performance of our methods is illustrated using the CASIA Gait Database.

Correlation based method for comparing and reconstructing quasi-identical two-dimensional structures

International Nuclear Information System (INIS)

Mejia-Barbosa, Y.

2000-03-01

We show a method for comparing and reconstructing two similar amplitude-only structures, which are composed by the same number of identical apertures. The structures are two-dimensional and differ only in the location of one of the apertures. The method is based on a subtraction algorithm, which involves the auto-correlations and cross-correlation functions of the compared structures. Experimental results illustrate the feasibility of the method. (author)

Computation of two-dimensional isothermal flow in shell-and-tube heat exchangers

International Nuclear Information System (INIS)

Carlucci, L.N.; Galpin, P.F.; Brown, J.D.; Frisina, V.

1983-07-01

A computational procedure is outlined whereby two-dimensional isothermal shell-side flow distributions can be calculated for tube bundles having arbitrary boundaries and flow blocking devices, such as sealing strips, defined in arbitrary locations. The procedure is described in some detail and several computed results are presented to illustrate the robustness and generality of the method

Confrontation and Alienation: Education's Flawed Response to Religious Textbook Objections.

Science.gov (United States)

Balajthy, Ernest

Recent controversies over textbooks illustrate objections held by Evangelicals to "secular humanism" in the schools. Educators automatically tend to assume that all religious objections to curricula are clear-cut attempts at censorship. This confrontational attitude on the part of educators can lead to alienation of minority religious…

A tankönyvi illusztrációk és képek szerepe az oktatásban - The Educational Role of Coursebook Illustrations

Directory of Open Access Journals (Sweden)

MARÓDI, Ágnes

2013-12-01

Full Text Available Since Comenius, demonstration with illustrations as a didactic principle has had an essential role in editing not only medical-, but other textbooks as well. Illustrations and pictures provide the possibility of presenting certain elements of the world in miniature or in enlarged form. For children, learning with textbooks rich in illustrations and pictures is especially important. Th e question is in what proportion these pictures occur in textbooks, how efficiently they foster the learning process and to what extent they correspond with the text in the coursebook. We can also find pictures whose only purpose is to increase the number of pages without any educational purpose. The textbook publishers use motivational pictures adequate to the age and psychological capacities of students in order to facilitate the reception, comprehension, interpretation and recollection. Lately it has also become frequent to publish educational material in digital form whose great advantage is that it captivates the students’ attention more easily by playing sounds, videos or animations alongside the pictures. Recalling visual impressions is faster, if students see pictures related to text which they are reading. This is the reason why the utilisation of pictures and illustrations in textbook is of primary importance.

The Oil Drop Experiment: An Illustration of Scientific Research Methodology and its Implications for Physics Textbooks

Science.gov (United States)

Rodriguez, Maria A.; Niaz, Mansoor

2004-01-01

The objectives of this study are: (1) evaluation of the methodology used in recent search for particles with fractional electrical charge (quarks) and its implications for understanding the scientific research methodology of Millikan; (2) evaluation of 43 general physics textbooks and 11 laboratory manuals, with respect to the oil drop experiment,…

Libraries Leading the Way on the Textbook Problem

OpenAIRE

Billings, Marilyn; Cross, William M; O'Connell, Brendan; Raschke, Gregory; Roh, Charlotte

2015-01-01

Escalating textbook costs and continually evolving technologies for delivering course content have combined to place the “textbook problem” at a boiling point ripe for systemic change. This article describes two efforts to address the “textbook problem” by offering incentive grants to faculty members who adopt, adapt, or create open educational resources (OERs) to replace costly textbooks. It describes programs at UMass Amherst and North Carolina State University and discusses the role of the...

Sociology of health textbooks and narratives: historical significance.

Science.gov (United States)

Nunes, Everardo Duarte

2016-03-01

This article has as its starting point two central ideas: textbooks as a means of production and dissemination of knowledge and narrative as an approach. After a brief review of studies on health/medical sociology textbooks, I analyze a few of these textbooks from the 1900-2012 period, produced in the United States and England. I have selected eleven textbooks which I thought were representative. In addition to a content analysis, the textbooks are located within the process of constitution of the health/medical sociology with brief references to the biographies of the authors. The textbooks analyzed were classified according to the main narrative features: doctor-centered; interdisciplinary; pedagogical; analytical; almost autobiographical; critical; and synthetic-reflective. In the final remarks, some points about the textbooks, limits and possibilities are presented.

Conjunctions in Malaysian Secondary School English Language Textbooks

Directory of Open Access Journals (Sweden)

Alicia Philip

2012-05-01

Full Text Available The present research aims to investigate the distribution pattern of conjunctions and their ranking in two different corpora, namely the Malaysian school English language Textbook Corpus (Textbook Corpus and the British National Corpus (BNC. An additional objective of the study was to find out how conjunctions had been presented in the Malaysian school English language textbooks (Forms 1-5. The method applied was qualitative content analysis. The findings indicated that coordinating conjunctions were the most frequent conjunctions that occurred in the five textbooks followed by subordinating and correlative conjunctions. The ranking of the different types of conjunctions in the Textbook Corpus was similar to that of the reference corpus, BNC. The results also indicated that the textbooks failed to present conjunctions effectively. The findings are expected to help textbook developers or language teachers in developing or adapting learning materials. Keywords: Conjunctions, Textbook evaluation, Distribution patterns

Two-dimensional divertor modeling and scaling laws

International Nuclear Information System (INIS)

Catto, P.J.; Connor, J.W.; Knoll, D.A.

1996-01-01

Two-dimensional numerical models of divertors contain large numbers of dimensionless parameters that must be varied to investigate all operating regimes of interest. To simplify the task and gain insight into divertor operation, we employ similarity techniques to investigate whether model systems of equations plus boundary conditions in the steady state admit scaling transformations that lead to useful divertor similarity scaling laws. A short mean free path neutral-plasma model of the divertor region below the x-point is adopted in which all perpendicular transport is due to the neutrals. We illustrate how the results can be used to benchmark large computer simulations by employing a modified version of UEDGE which contains a neutral fluid model. (orig.)

[Investigation of the publishing and using status of college genetics textbooks in China].

Science.gov (United States)

Chen, Xiwen; Chen, Defu

2014-04-01

Using Wenjin Search of the National Library of China, it was found that 895 genetics textbooks for Chinese colleges, including 588 (67.5%) theoretical books, 122 (13.6%) experimental books and 185 (20.7%) teaching reference books, have been published since College Entrance Examination resumed. Most of these books belong to medical genetics, followed by general genetics, while the books on plant genetics, animal genetics or microbial genetics are relatively few. In these search results, 91 had the same name of Medical Genetics, professor Ji Zuo is the most productive author, who edited 9 genetics textbooks, and Science Press Ltd. is the most productive press, which published 179 (20%) genetics textbooks. The questionnaire survey showed that "Genetics" (Second Edition) edited by Zhuohua Dai is the most widely used textbooks in the Chinese colleges, while the mainly used experimental books are the handouts or self-edited textbooks. Finally, we analyzed the problems currently existed in the textbooks, such as slowly updating cycle, less supports, lots of books with the same name, lack of scientific stories, very rare and unique illustrations, too full printed pages, and also provided the proposed solution.

The Treatment of the Monotheistic Religions in World History High School Textbooks: A Comparison of Sample Editions 2001-2007

Science.gov (United States)

Allen, Jason Eugene

2009-01-01

This study examines the treatment of the three most practiced monotheistic religions, Christianity, Islam, and Judaism, within the pages of High School World History Textbooks. The results find that within World History textbooks Christianity and Islam receive more coverage than Judaism in narrative content, word usage, illustrations, and…

Two-dimensional goodness-of-fit testing in astronomy

International Nuclear Information System (INIS)

Peacock, J.A

1983-01-01

This paper deals with the techniques available to test for consistency between the empirical distribution of data points on a plane and a hypothetical density law. Two new statistical tests are developed. The first is a two-dimensional version of the Kolmogorov-Smirnov test, for which the distribution of the test statistic is investigated using a Monte Carlo method. This test is found in practice to be very nearly distribution-free, and empirical formulae for the confidence levels are given. Secondly, the method of power-spectrum analysis is extended to deal with cases in which the null hypothesis is not a uniform distribution. These methods are illustrated by application to the distribution of quasar candidates found on an objective-prism plate of the Virgo Cluster. (author)

Gendered Word (Or World): Sexism in Philippine Preschool English Language Textbooks

Science.gov (United States)

Tarrayo, Veronico Nogales

2014-01-01

Adhering to the notion that language learning is necessarily a culture-learning process, this paper explores the issue of sexism in six Philippine preschool English language textbooks. The study adopts the qualitative-quantitative approach in examining the following categories: gender visibility (illustrations), "firstness",…

The Transmission of Cultural Values via EFL Textbooks in China

Science.gov (United States)

Li, Jingyi

2016-01-01

This article examines the cultural values conveyed via texts and illustrations in EFL (English as a foreign language) textbooks currently in use in China. The large number of cultural values represented include patriotism, respect, diligence, collectivism, and equitable gender roles. These show that the national curriculum has been implemented in…

Global Anomaly Detection in Two-Dimensional Symmetry-Protected Topological Phases

Science.gov (United States)

Bultinck, Nick; Vanhove, Robijn; Haegeman, Jutho; Verstraete, Frank

2018-04-01

Edge theories of symmetry-protected topological phases are well known to possess global symmetry anomalies. In this Letter we focus on two-dimensional bosonic phases protected by an on-site symmetry and analyze the corresponding edge anomalies in more detail. Physical interpretations of the anomaly in terms of an obstruction to orbifolding and constructing symmetry-preserving boundaries are connected to the cohomology classification of symmetry-protected phases in two dimensions. Using the tensor network and matrix product state formalism we numerically illustrate our arguments and discuss computational detection schemes to identify symmetry-protected order in a ground state wave function.

Quantum entanglement and phase transition in a two-dimensional photon-photon pair model

International Nuclear Information System (INIS)

Zhang Jianjun; Yuan Jianhui; Zhang Junpei; Cheng Ze

2013-01-01

We propose a two-dimensional model consisting of photons and photon pairs. In the model, the mixed gas of photons and photon pairs is formally equivalent to a two-dimensional system of massive bosons with non-vanishing chemical potential, which implies the existence of two possible condensate phases. Using the variational method, we discuss the quantum phase transition of the mixed gas and obtain the critical coupling line analytically. Moreover, we also find that the phase transition of the photon gas can be interpreted as enhanced second harmonic generation. We then discuss the entanglement between photons and photon pairs. Additionally, we also illustrate how the entanglement between photons and photon pairs can be associated with the phase transition of the system.

Communicative Textbooks: English Language Textbooks in Iranian Secondary School

Directory of Open Access Journals (Sweden)

Dahmardeh, Mahdi

2009-01-01

Full Text Available English language teaching materials (textbooks play an important role in many language classrooms, but recently there have been a lot of debates within the English language teaching profession based on the actual role that materials play in teaching English as a foreign language. Arguments have encompassed both the potential and the limitations of materials used for 'guiding' students through the learning processes and curriculum as well as the needs and preferences of teachers who are using the textbooks that are available. Other issues that have arisen in recent years include textbook design and practicality, methodological validity, the role of textbooks in innovation, the authenticity of materials in terms of their representation of language, communicative textbooks, and balance in presenting the language skills as well as cultural components.The purpose of this article is to report the findings of a study carried out in 2006 into how Iranian textbooks could be made more communicative. The textbooks referred to are three English language textbooks, which are currently used in Iranian Secondary Schools. Although the work has been done within Iranian context, many suggestions could be applied to other foreign/second language situations.I will start my discussion by presenting an overview about the English language teaching in Iran, before and after the revolution. This will be followed by presenting the findings of this research that would include the Iranian ELT curriculum, the questionnaire survey (author's and teachers' perspectives as well as their discomfort will be addressed as well as introducing the English language coursebooks for secondary schools in Iran (topic, progression, structure of the lessons, types of exercises etc.. I will then present a discussion on findings of this research which would be a detailed exemplary criticism and suggestions for changes to make the materials communicative.The findings of this explanatory case

Textbook research as scientific research: towards a common ground for research on mathematics textbooks

OpenAIRE

Fan, Lianghuo

2011-01-01

This article explores research issues and methods of textbook research. Drawing on literatures and the author’s own work in the area of mathematics textbook research, it conceptualizes textbooks as an intermediate variable in the context of education and hence defines textbook research as disciplined inquiry into issues about textbooks and the relationships between textbooks and other factors in education. Furthermore, it argues that to further advance the field of textbook research, research...

Electronic Geometry Textbook: A Geometric Textbook Knowledge Management System

OpenAIRE

Chen, Xiaoyu

2010-01-01

Electronic Geometry Textbook is a knowledge management system that manages geometric textbook knowledge to enable users to construct and share dynamic geometry textbooks interactively and efficiently. Based on a knowledge base organizing and storing the knowledge represented in specific languages, the system implements interfaces for maintaining the data representing that knowledge as well as relations among those data, for automatically generating readable documents for viewing or printing, ...

Approximate solutions of the two-dimensional integral transport equation by collision probability methods

International Nuclear Information System (INIS)

Sanchez, Richard

1977-01-01

A set of approximate solutions for the isotropic two-dimensional neutron transport problem has been developed using the Interface Current formalism. The method has been applied to regular lattices of rectangular cells containing a fuel pin, cladding and water, or homogenized structural material. The cells are divided into zones which are homogeneous. A zone-wise flux expansion is used to formulate a direct collision probability problem within a cell. The coupling of the cells is made by making extra assumptions on the currents entering and leaving the interfaces. Two codes have been written: the first uses a cylindrical cell model and one or three terms for the flux expansion; the second uses a two-dimensional flux representation and does a truly two-dimensional calculation inside each cell. In both codes one or three terms can be used to make a space-independent expansion of the angular fluxes entering and leaving each side of the cell. The accuracies and computing times achieved with the different approximations are illustrated by numerical studies on two benchmark pr

Some Perceptions of English Geography Textbook Authors on Writing Textbooks

Science.gov (United States)

Lee, Jongwon; Catling, Simon

2016-01-01

There has been much research into the nature and uses of school geography textbooks as teaching resources, yet the perceptions of their authors have been neglected. This study investigated the perspectives of a sample of authors of English primary and secondary school geography textbooks on their experiences as textbook authors. It enquired into…

Crustal geomagnetic field - Two-dimensional intermediate-wavelength spatial power spectra

Science.gov (United States)

Mcleod, M. G.

1983-01-01

Two-dimensional Fourier spatial power spectra of equivalent magnetization values are presented for a region that includes a large portion of the western United States. The magnetization values were determined by inversion of POGO satellite data, assuming a magnetic crust 40 km thick, and were located on an 11 x 10 array with 300 km grid spacing. The spectra appear to be in good agreement with values of the crustal geomagnetic field spatial power spectra given by McLeod and Coleman (1980) and with the crustal field model given by Serson and Hannaford (1957). The spectra show evidence of noise at low frequencies in the direction along the satellite orbital track (N-S). indicating that for this particular data set additional filtering would probably be desirable. These findings illustrate the value of two-dimensional spatial power spectra both for describing the geomagnetic field statistically and as a guide for diagnosing possible noise sources.

Comparing the development of the multiplication of fractions in Turkish and American textbooks

Science.gov (United States)

Kar, Tuğrul; Güler, Gürsel; Şen, Ceylan; Özdemir, Ercan

2018-02-01

This study analyzed the methods used to teach the multiplication of fractions in Turkish and American textbooks. Two Turkish textbooks and two American textbooks, Everyday Mathematics (EM) and Connected Mathematics 3 (CM), were analyzed. The analyses focused on the content and the nature of the mathematical problems presented in the textbooks. The findings of the study showed that the American textbooks aimed at developing conceptual understanding first and then procedural fluency, whereas the Turkish textbooks aimed at developing both concurrently. The American textbooks provided more opportunities for different computational strategies. The solutions to most problems in all textbooks required a single computational step, a numerical answer, and procedural knowledge. Furthermore, compared with the Turkish textbooks, the American textbooks contained a greater number of problems that required high-level cognitive skills such as mathematical reasoning.

Quickscan open textbooks

NARCIS (Netherlands)

Pierre Gorissen

2015-01-01

Deze quickscan open textbooks is uitgevoerd in opdracht van SURFnet ter voorbereiding van het seminar over open textbooks op 26 november 2015. Het is nadrukkelijk een quickscan, de beschikbare tijd om literatuur te verzamelen en te beoordelen rond open textbooks was begrensd. Deze quickscan heeft

Discrimination in Textbooks

OpenAIRE

大津, 尚志

1996-01-01

In this paper, I deal with the issues which concern discriminations in textbooks.In America, they have paid special attentions to these problems since 1960's. They made guidelines for textbooks to check various kinds of discriminative descriptions and tried to make textbooks to meet these standards. In this respects I would examine the present states about textbooks in America and would compare them to the Japanese ones. That would be useful, I believe, when we consider these issues in Japan.

The Study of Two-Dimensional Oscillations Using a Smartphone Acceleration Sensor: Example of Lissajous Curves

Science.gov (United States)

Tuset-Sanchis, Luis; Castro-Palacio, Juan C.; Gómez-Tejedor, José A.; Manjón, Francisco J.; Monsoriu, Juan A.

2015-01-01

A smartphone acceleration sensor is used to study two-dimensional harmonic oscillations. The data recorded by the free android application, Accelerometer Toy, is used to determine the periods of oscillation by graphical analysis. Different patterns of the Lissajous curves resulting from the superposition of harmonic motions are illustrated for…

Multiple Attribute Group Decision-Making Methods Based on Trapezoidal Fuzzy Two-Dimensional Linguistic Partitioned Bonferroni Mean Aggregation Operators.

Science.gov (United States)

Yin, Kedong; Yang, Benshuo; Li, Xuemei

2018-01-24

In this paper, we investigate multiple attribute group decision making (MAGDM) problems where decision makers represent their evaluation of alternatives by trapezoidal fuzzy two-dimensional uncertain linguistic variable. To begin with, we introduce the definition, properties, expectation, operational laws of trapezoidal fuzzy two-dimensional linguistic information. Then, to improve the accuracy of decision making in some case where there are a sort of interrelationship among the attributes, we analyze partition Bonferroni mean (PBM) operator in trapezoidal fuzzy two-dimensional variable environment and develop two operators: trapezoidal fuzzy two-dimensional linguistic partitioned Bonferroni mean (TF2DLPBM) aggregation operator and trapezoidal fuzzy two-dimensional linguistic weighted partitioned Bonferroni mean (TF2DLWPBM) aggregation operator. Furthermore, we develop a novel method to solve MAGDM problems based on TF2DLWPBM aggregation operator. Finally, a practical example is presented to illustrate the effectiveness of this method and analyses the impact of different parameters on the results of decision-making.

Comparative analysis of a nontraditional general chemistry textbook and selected traditional textbooks used in Texas community colleges

Science.gov (United States)

Salvato, Steven Walter

The purpose of this study was to analyze questions within the chapters of a nontraditional general chemistry textbook and the four general chemistry textbooks most widely used by Texas community colleges in order to determine if the questions require higher- or lower-order thinking according to Bloom's taxonomy. The study employed quantitative methods. Bloom's taxonomy (Bloom, Engelhart, Furst, Hill, & Krathwohl, 1956) was utilized as the main instrument in the study. Additional tools were used to help classify the questions into the proper category of the taxonomy (McBeath, 1992; Metfessel, Michael, & Kirsner, 1969). The top four general chemistry textbooks used in Texas community colleges and Chemistry: A Project of the American Chemical Society (Bell et al., 2005) were analyzed during the fall semester of 2010 in order to categorize the questions within the chapters into one of the six levels of Bloom's taxonomy. Two coders were used to assess reliability. The data were analyzed using descriptive and inferential methods. The descriptive method involved calculation of the frequencies and percentages of coded questions from the books as belonging to the six categories of the taxonomy. Questions were dichotomized into higher- and lower-order thinking questions. The inferential methods involved chi-square tests of association to determine if there were statistically significant differences among the four traditional college general chemistry textbooks in the proportions of higher- and lower-order questions and if there were statistically significant differences between the nontraditional chemistry textbook and the four traditional general chemistry textbooks. Findings indicated statistically significant differences among the four textbooks frequently used in Texas community colleges in the number of higher- and lower-level questions. Statistically significant differences were also found among the four textbooks and the nontraditional textbook. After the analysis of

Equivalence of two-dimensional gravities

International Nuclear Information System (INIS)

Mohammedi, N.

1990-01-01

The authors find the relationship between the Jackiw-Teitelboim model of two-dimensional gravity and the SL(2,R) induced gravity. These are shown to be related to a two-dimensional gauge theory obtained by dimensionally reducing the Chern-Simons action of the 2 + 1 dimensional gravity. The authors present an explicit solution to the equations of motion of the auxiliary field of the Jackiw-Teitelboim model in the light-cone gauge. A renormalization of the cosmological constant is also given

STUDY OF GEOGRAPHY TEXTBOOKS FOR 9th, 10th, 11th AND 12th GRADES. CASE STUDY: MAHARASHTRA STATE, INDIA

Directory of Open Access Journals (Sweden)

MARIANA-DOINA CÎINEANU

2017-02-01

Full Text Available The introduction conveys some data on learning in India and on designing Geography textbooks in this country. The present paper is reliant on four Geography textbooks, ranging from the 9th to the 12th grade. As regards each textbook, the study considers their learning units, then analyses their structure, the unitary way of designing them, the components of the panels of authors, the texts, illustrative materials, drills, learning activities, language, the wealth of Geography lexis, and the glossary.

History Textbooks at the New Century: A Report of the American Textbook Council.

Science.gov (United States)

Sewall, Gilbert T.

The American Textbook Council identified the nation's leading social studies textbooks based on estimated volume of sales and on adoptions in California, Indiana, North Carolina, Florida, and New York. Three multi-volume elementary-level programs and about a dozen secondary-level history textbooks command the market. The history textbooks at the…

Two-dimensional metamaterial optics

International Nuclear Information System (INIS)

Smolyaninov, I I

2010-01-01

While three-dimensional photonic metamaterials are difficult to fabricate, many new concepts and ideas in the metamaterial optics can be realized in two spatial dimensions using planar optics of surface plasmon polaritons. In this paper we review recent progress in this direction. Two-dimensional photonic crystals, hyperbolic metamaterials, and plasmonic focusing devices are demonstrated and used in novel microscopy and waveguiding schemes

Plutonium and textbooks

International Nuclear Information System (INIS)

Silver, G.L.

2008-01-01

Chemical equilibrium is not characterized by equilibrium constants alone. At least one conservation principle is necessary. Textbook descriptions of plutonium chemistry that are based on two-reaction-product disproportionation equations, or do not recognize the conservation principles, are incomplete and potentially misleading. (author)

The institution as e-textbook publisher

Directory of Open Access Journals (Sweden)

Andrew Barker

2015-11-01

Full Text Available Providing students with sufficient copies of core textbooks is an increasing challenge in an age of ever higher fees, economic realities and heightened student expectations regarding provision of library resources. This article outlines the partnership between the University of Liverpool Library and Liverpool University Press (LUP, which has progressed from the creation of a library advisory board to the co-creation of two bespoke and open access (OA e-textbooks as part of a Jisc-funded project. It tells the story of why we have gone down this route at Liverpool and what we hope to gain from the creation of these e-textbooks.

Secondary-school chemistry textbooks in the 19th century

Directory of Open Access Journals (Sweden)

Milanović Vesna D.

2015-01-01

Full Text Available The teaching of chemistry in Serbia as a separate subject dates from 1874. The first secondary-school chemistry textbooks appeared in the second half of the 19th century. The aim of this paper is to gain insight, by analysing two secondary-school chemistry textbooks, written by Sima Lozanić (1895 and Mita Petrović (1892, into what amount of scientific knowledge from the sphere of chemistry was presented to secondary school students in Serbia in the second half of the 19th century, and what principles textbooks written at the time were based on. Within the framework of the research conducted, we defined the criteria for assessing the quality of secondary-school chemistry textbooks in the context of the time they were written in. The most important difference between the two textbooks under analysis that we found pertained to the way in which their contents were organized. Sima Lozanić’s textbook is characterized by a greater degree of systematicness when it comes to the manner of presenting its contents and consistency of approach throughout the book. In both textbooks one can perceive the authors’ attempts to link chemistry-related subjects to everyday life, and to point out the practical significance of various substances, as well as their toxicness.

Textbooks in the EFL classroom: Defining, assessing and analyzing

Directory of Open Access Journals (Sweden)

Radić-Bojanić Biljana B.

2016-01-01

Full Text Available The aim of this paper is to define textbooks, analyze their advantages and disadvantages and to explicate the process of textbook selection and reasons for analyzing textbooks. The paper describes two reasons for performing a textbook analysis: evaluating for potential and evaluating for suitability, and further states various processes of textbook content analysis including the analysis of the stated aims and objectives, learner needs, their abilities and preferences, as well as the establishment of criteria in relation to previously set objectives. The paper concludes by stating that the task that teachers are faced with when selecting and evaluating textbooks is not that is an easy one, but it is crucial. With the assistance of clear guidelines and detailed criteria, they should be able to make an informed decision and choose a textbook that is most suitable for the requirements of their specific classroom context.

INSTRUCTIONAL MANUALS OF BOUNDARY‐WORK: PSYCHOLOGY TEXTBOOKS, STUDENT SUBJECTIVITIES, AND DISCIPLINARY HISTORIOGRAPHIES

Science.gov (United States)

FLIS, IVAN

2016-01-01

This article aims to provide an overview of the historiography of psychology textbooks. In the overview, I identify and describe in detail two strands of writing histories of introductory textbooks of psychology and juxtapose them to provide an integrated historiography of textbooks in psychology. One strand is developed by teachers of psychology—first as a general approach for investigating textbooks in a pedagogical setting, and then later upgraded into a full history of psychology textbooks in America. The other strand follows a more familiar perspective of historians of science and historians of psychology who build on various post‐Kuhnian and post‐Foucauldian perspectives on textbooks. I make an argument for integrating these two views for a more comprehensive historiography of textbooks in psychology, recasting textbooks as objects of research and sources that are interesting sui generis for historians of psychology in their investigations. PMID:27152736

The Educational Design of Textbooks: A Text for Being Interdisciplinary

Science.gov (United States)

Golding, Clinton

2014-01-01

This paper provides insights into both the educational design of textbooks and interdisciplinary education. The author introduces two educational principles for textbook design--instructional alignment and balancing diversity and meaningful guidance for readers--and applies them to writing his own textbook chapter for being interdisciplinary. The…

Evaluation of WorldView Textbooks; Textbooks Taught at a Military University

Science.gov (United States)

Khalili, Masoud; Jodai, Hojat

2012-01-01

This paper intends to evaluate the WorldView series textbooks of English learning, which are being taught at an Iranian military university foreign language center. No textbook evaluation had been conducted by the university administration prior to the introduction of the textbooks to the language program. Theorists in the field of ELT textbook…

Achieving Textbook Multigrid Efficiency for Hydrostatic Ice Sheet Flow

KAUST Repository

Brown, Jed; Smith, Barry; Ahmadia, Aron

2013-01-01

The hydrostatic equations for ice sheet flow offer improved fidelity compared with the shallow ice approximation and shallow stream approximation popular in today's ice sheet models. Nevertheless, they present a serious bottleneck because they require the solution of a three-dimensional (3D) nonlinear system, as opposed to the two-dimensional system present in the shallow stream approximation. This 3D system is posed on high-aspect domains with strong anisotropy and variation in coefficients, making it expensive to solve with current methods. This paper presents a Newton--Krylov multigrid solver for the hydrostatic equations that demonstrates textbook multigrid efficiency (an order of magnitude reduction in residual per iteration and solution of the fine-level system at a small multiple of the cost of a residual evaluation). Scalability on Blue Gene/P is demonstrated, and the method is compared to various algebraic methods that are in use or have been proposed as viable approaches.

Achieving Textbook Multigrid Efficiency for Hydrostatic Ice Sheet Flow

KAUST Repository

Brown, Jed

2013-03-12

The hydrostatic equations for ice sheet flow offer improved fidelity compared with the shallow ice approximation and shallow stream approximation popular in today\\'s ice sheet models. Nevertheless, they present a serious bottleneck because they require the solution of a three-dimensional (3D) nonlinear system, as opposed to the two-dimensional system present in the shallow stream approximation. This 3D system is posed on high-aspect domains with strong anisotropy and variation in coefficients, making it expensive to solve with current methods. This paper presents a Newton--Krylov multigrid solver for the hydrostatic equations that demonstrates textbook multigrid efficiency (an order of magnitude reduction in residual per iteration and solution of the fine-level system at a small multiple of the cost of a residual evaluation). Scalability on Blue Gene/P is demonstrated, and the method is compared to various algebraic methods that are in use or have been proposed as viable approaches.

What Makes a Top-Selling Textbook? Comparing Characteristics of AIS Textbooks

Science.gov (United States)

Badua, Frank; Sharifi, Mohsen; Mendez Mediavilla, Francis

2014-01-01

The factors involved in the selection of accounting textbooks are under-investigated, and most of the research is survey-based, largely ignoring the information that could be analyzed by direct inspection of textbook content and its impact on textbook selection. In this study the authors fill this lacuna by deploying content analysis of the…

Identifying Two-Dimensional Z 2 Antiferromagnetic Topological Insulators

Science.gov (United States)

Bègue, F.; Pujol, P.; Ramazashvili, R.

2018-01-01

We revisit the question of whether a two-dimensional topological insulator may arise in a commensurate Néel antiferromagnet, where staggered magnetization breaks the symmetry with respect to both elementary translation and time reversal, but retains their product as a symmetry. In contrast to the so-called Z 2 topological insulators, an exhaustive characterization of antiferromagnetic topological phases with the help of topological invariants has been missing. We analyze a simple model of an antiferromagnetic topological insulator and chart its phase diagram, using a recently proposed criterion for centrosymmetric systems [13]. We then adapt two methods, originally designed for paramagnetic systems, and make antiferromagnetic topological phases manifest. The proposed methods apply far beyond the particular examples treated in this work, and admit straightforward generalization. We illustrate this by two examples of non-centrosymmetric systems, where no simple criteria have been known to identify topological phases. We also present, for some cases, an explicit construction of edge states in an antiferromagnetic topological insulator.

INSTRUCTIONAL MANUALS OF BOUNDARY-WORK: PSYCHOLOGY TEXTBOOKS, STUDENT SUBJECTIVITIES, AND DISCIPLINARY HISTORIOGRAPHIES.

Science.gov (United States)

Flis, Ivan

2016-07-01

This article aims to provide an overview of the historiography of psychology textbooks. In the overview, I identify and describe in detail two strands of writing histories of introductory textbooks of psychology and juxtapose them to provide an integrated historiography of textbooks in psychology. One strand is developed by teachers of psychology-first as a general approach for investigating textbooks in a pedagogical setting, and then later upgraded into a full history of psychology textbooks in America. The other strand follows a more familiar perspective of historians of science and historians of psychology who build on various post-Kuhnian and post-Foucauldian perspectives on textbooks. I make an argument for integrating these two views for a more comprehensive historiography of textbooks in psychology, recasting textbooks as objects of research and sources that are interesting sui generis for historians of psychology in their investigations. © 2016 The Authors. Journal of the History of the Behavioral Sciences Published by Wiley Periodicals, Inc.

The physics and engineering aspects of radiology. Textbook with questions and answers

International Nuclear Information System (INIS)

Link, T.M.; Heppe, A.; Meier, N.; Fiebich, M.

1994-01-01

The textbook formulates and answers the questions encountered in practice by students in the radiology professions, covering the physics and engineering aspects as well as quality control and the relevant requirements set by the X-ray Ordinance and the Quality Assurance Guide issued by the Bundesaerztekammer for diagnostic radiography and computed tomography. The text is accompanied by simplified illustrations that are easy to remember. The book is intended to serve as a textbook for readers preparing for their examination as a medical specialist, or for participants of obligatory courses in radiological protection, or radiographers. Readers will also find it useful as a refresher course. (orig.) [de

A Kronecker product splitting preconditioner for two-dimensional space-fractional diffusion equations

Science.gov (United States)

Chen, Hao; Lv, Wen; Zhang, Tongtong

2018-05-01

We study preconditioned iterative methods for the linear system arising in the numerical discretization of a two-dimensional space-fractional diffusion equation. Our approach is based on a formulation of the discrete problem that is shown to be the sum of two Kronecker products. By making use of an alternating Kronecker product splitting iteration technique we establish a class of fixed-point iteration methods. Theoretical analysis shows that the new method converges to the unique solution of the linear system. Moreover, the optimal choice of the involved iteration parameters and the corresponding asymptotic convergence rate are computed exactly when the eigenvalues of the system matrix are all real. The basic iteration is accelerated by a Krylov subspace method like GMRES. The corresponding preconditioner is in a form of a Kronecker product structure and requires at each iteration the solution of a set of discrete one-dimensional fractional diffusion equations. We use structure preserving approximations to the discrete one-dimensional fractional diffusion operators in the action of the preconditioning matrix. Numerical examples are presented to illustrate the effectiveness of this approach.

Introduction to the conformational investigation of peptides and proteins by using two-dimensional proton NMR experiments

International Nuclear Information System (INIS)

Neumann, J.M.; Macquaire, F.

1991-01-01

This report presents the elementary bases for an initiation to the conformational study of peptides and proteins by using two-dimensional proton NMR experiments. First, some general features of protein structures are summarized. A second chapter is devoted to the basic NMR experiments and to the spectral parameters which provide a structural information. This description is illustrated by NMR spectra of peptides. The third chapter concerns the most standard two-dimensional proton NMR experiments and their use for a conformational study of peptides and proteins. Lastly, an example of NMR structural investigation of a peptide is reported [fr

Student Voice in Textbook Evaluation: Comparing Open and Restricted Textbooks

Science.gov (United States)

Woodward, Scott; Lloyd, Adam; Kimmons, Royce

2017-01-01

Advocates for student voice in higher education believe students should have the right and power to engage in much of the decision-making traditionally dominated by instructors or administrators. This qualitative study examines the role of student voice in the evaluation of textbook quality. Evaluators included two graduate students enrolled in a…

Reparametrization BRS cohomology in two-dimensional gravity and non-critical string theories

International Nuclear Information System (INIS)

Fujikawa, Kazuo.

1989-07-01

Various anomalies related to the gravitational BRS current in two-dimensional theories are explained from the view point of the path integral formalism, and the algebraic properties of composite operators are confirmed by the operator product technique. The implications of the reparametrization BRS cohomology on possible non-critical string theory are illustrated by using the string field theoretical technique. The appearance of the Higgs (or Stueckelberg)-like mechanism due to the Liouville freedom is shown. (author)

Controlling spatiotemporal chaos in one- and two-dimensional coupled logistic map lattices

International Nuclear Information System (INIS)

Astakhov, V.V.; Anishchenko, V.S.; Strelkova, G.I.; Shabunin, A.V.

1996-01-01

A method of control of spatiotemporal chaos in lattices of coupled maps is proposed in this work. Forms of spatiotemporal perturbations of a system parameter are analytically determined for one- and two-dimensional logistic map lattices with different kinds of coupling to stabilize chosen spatiotemporal states previously unstable. The results are illustrated by numerical simulation. Controlled transition from the regime of spatiotemporal chaos to the previously chosen regular spatiotemporal patterns is demonstrated. copyright 1996 American Institute of Physics

Textbook America.

Science.gov (United States)

Karp, Walter

1980-01-01

Focuses on how political attitudes have been influenced by American history textbooks at various times throughout history. Excerpts from traditional and revisionist textbooks are presented, with emphasis on "America Revised" by Frances FitzGerald. Journal available from Harper's Magazine Co., 2 Park Ave., New York, NY 10016. (DB)

Chemical potential of one-dimensional simple harmonic oscillators

International Nuclear Information System (INIS)

Mungan, Carl E

2009-01-01

Expressions for the chemical potential of an Einstein solid, and of ideal Fermi and Bose gases in an external one-dimensional oscillatory trap, are calculated by two different methods and are all found to share the same functional form. These derivations are easier than traditional textbook calculations for an ideal gas in an infinite three-dimensional square well. Furthermore, the results indicate some important features of chemical potential that could promote student learning in an introductory course in statistical mechanics at the undergraduate level.

Development of monograph titled "augmented chemistry aldehida & keton" with 3 dimensional (3D) illustration as a supplement book on chemistry learning

Science.gov (United States)

Damayanti, Latifah Adelina; Ikhsan, Jaslin

2017-05-01

Integration of information technology in education more rapidly performed in a medium of learning. Three-dimensional (3D) molecular modeling was performed in Augmented Reality as a tangible manifestation of increasingly modern technology utilization. Based on augmented reality, three-dimensional virtual object is projected in real time and the exact environment. This paper reviewed the uses of chemical learning supplement book of aldehydes and ketones which are equipped with three-dimensional molecular modeling by which students can inspect molecules from various viewpoints. To plays the 3D illustration printed on the book, smartphones with the open-source software of the technology based integrated Augmented Reality can be used. The aims of this research were to develop the monograph of aldehydes and ketones with 3 dimensional (3D) illustrations, to determine the specification of the monograph, and to determine the quality of the monograph. The quality of the monograph is evaluated by experiencing chemistry teachers on the five aspects of contents/materials, presentations, language and images, graphs, and software engineering, resulted in the result that the book has a very good quality to be used as a chemistry learning supplement book.

Comparing the Development of the Multiplication of Fractions in Turkish and American Textbooks

Science.gov (United States)

Kar, Tugrul; Güler, Gürsel; Sen, Ceylan; Özdemir, Ercan

2018-01-01

This study analyzed the methods used to teach the multiplication of fractions in Turkish and American textbooks. Two Turkish textbooks and two American textbooks, "Everyday Mathematics" (EM) and "Connected Mathematics 3" (CM), were analyzed. The analyses focused on the content and the nature of the mathematical problems…

Principles of economics textbooks

DEFF Research Database (Denmark)

Madsen, Poul Thøis

2012-01-01

Has the financial crisis already changed US principles of economics textbooks? Rather little has changed in individual textbooks, but taken as a whole ten of the best-selling textbooks suggest rather encompassing changes of core curriculum. A critical analysis of these changes shows how individual...

On the two-dimensional Saigo-Maeda fractional calculus asociated with two-dimensional Aleph TRANSFORM

Directory of Open Access Journals (Sweden)

Dinesh Kumar

2013-11-01

Full Text Available This paper deals with the study of two-dimensional Saigo-Maeda operators of Weyl type associated with Aleph function defined in this paper. Two theorems on these defined operators are established. Some interesting results associated with the H-functions and generalized Mittag-Leffler functions are deduced from the derived results. One dimensional analog of the derived results is also obtained.

Journey to Textbook Affordability: An Investigation of Students’ Use of eTextbooks at Multiple Campuses

OpenAIRE

Eun-Ok Baek; James Monaghan

2013-01-01

eTextbooks have steadily and recently more rapidly penetrated the textbook market. In order to effectively support students’ learning, it is important to comprehend students’ experiences using eTextbooks. This survey study was designed to gain an understanding of students’ experiences in using eTextbooks and variables that impact their experiences, perceptions, and attitudes towards eTextbooks. In a total of 33 courses, faculty members at five state university campuses in California participa...

Journey to Textbook Affordability: An Investigation of Students' Use of eTextbooks at Multiple Campuses

Science.gov (United States)

Baek, Eun-Ok; Monaghan, James

2013-01-01

eTextbooks have steadily and recently more rapidly penetrated the textbook market. In order to effectively support students' learning, it is important to comprehend students' experiences using eTextbooks. This survey study was designed to gain an understanding of students' experiences in using eTextbooks and variables that impact their…

The Future of Web Maps in Next Generation Textbooks

Science.gov (United States)

DiBiase, D.; Prasad, S.

2014-12-01

The reformation of the "Object Formerly Known as Textbook" (coined by the Chronicle of Higher Education) toward a digital future is underway. Emerging nextgen texts look less like electronic books ("ebooks") and more like online courseware. In addition to text and illustrations, nextgen textbooks for STEM subjects are likely to combine quizzes, grade management tools, support for social learning, and interactive media including web maps. Web maps are interactive, multi-scale, online maps that enable teachers and learners to explore, interrogate, and mash up the wide variety of map layers available in the cloud. This presentation will show how web maps coupled with interactive quizzes enable students' purposeful explorations and interpretations of spatial patterns related to humankind's interactions with the earth. Attendees will also learn about Esri's offer to donate ArcGIS Online web mapping subscriptions to every U.S. school as part of the President Obama's ConnectED initiative.

Two-dimensional nuclear magnetic resonance spectroscopy

International Nuclear Information System (INIS)

Bax, A.; Lerner, L.

1986-01-01

Great spectral simplification can be obtained by spreading the conventional one-dimensional nuclear magnetic resonance (NMR) spectrum in two independent frequency dimensions. This so-called two-dimensional NMR spectroscopy removes spectral overlap, facilitates spectral assignment, and provides a wealth of additional information. For example, conformational information related to interproton distances is available from resonance intensities in certain types of two-dimensional experiments. Another method generates 1 H NMR spectra of a preselected fragment of the molecule, suppressing resonances from other regions and greatly simplifying spectral appearance. Two-dimensional NMR spectroscopy can also be applied to the study of 13 C and 15 N, not only providing valuable connectivity information but also improving sensitivity of 13 C and 15 N detection by up to two orders of magnitude. 45 references, 10 figures

An Economic Analysis of Textbook Pricing and Textbook Markets. ACSFA College Textbook Cost Study Plan Proposal

Science.gov (United States)

Koch, James V.

2006-01-01

Between 1986 and 2004, textbook prices rose 186 percent in the United States, or slightly more than six percent per year. Meanwhile, other prices rose only about three percent per year. This paper examines the economic reasons why textbook prices have escalated so briskly and what reasonable alternatives are available that might slow down these…

On some classes of two-dimensional local models in discrete two-dimensional monatomic FPU lattice with cubic and quartic potential

International Nuclear Information System (INIS)

Quan, Xu; Qiang, Tian

2009-01-01

This paper discusses the two-dimensional discrete monatomic Fermi–Pasta–Ulam lattice, by using the method of multiple-scale and the quasi-discreteness approach. By taking into account the interaction between the atoms in the lattice and their nearest neighbours, it obtains some classes of two-dimensional local models as follows: two-dimensional bright and dark discrete soliton trains, two-dimensional bright and dark line discrete breathers, and two-dimensional bright and dark discrete breather. (condensed matter: structure, thermal and mechanical properties)

Two-dimensional models

International Nuclear Information System (INIS)

Schroer, Bert; Freie Universitaet, Berlin

2005-02-01

It is not possible to compactly review the overwhelming literature on two-dimensional models in a meaningful way without a specific viewpoint; I have therefore tacitly added to the above title the words 'as theoretical laboratories for general quantum field theory'. I dedicate this contribution to the memory of J. A. Swieca with whom I have shared the passion of exploring 2-dimensional models for almost one decade. A shortened version of this article is intended as a contribution to the project 'Encyclopedia of mathematical physics' and comments, suggestions and critical remarks are welcome. (author)

Textbook Reading Levels

Science.gov (United States)

Hopkins, Charles R.; Kim, Paul Y.

1974-01-01

Since the reading abilities of general business students vary from one individual to the next, the author's report on the readability of three general business textbooks to guide business teachers in their selection of textbooks. (AG)

Electronic textbooks: didactic aspect

Directory of Open Access Journals (Sweden)

Ivanova Elena O.

2016-01-01

Full Text Available The modern process of training proceeding in the information and education environment demands a textbook of a new format differing from that one of a traditional paper book. Research has shown that a new textbook is a specially designed subject information and education environment. Filling of this environment (the textbook - navigator, the textbook script, a set of materials for independent work, etc., structuring information (as the script of an educational process, the designer of a process of training, the integrator of the specified types is shown in the article. Characteristics of textbooks of a new generation are provided: orientation towards realizing the complete process of training from positing aims to a reflection of results, ensuring the maximum independence of pupils, accounting of specific features of pupils, granting opportunities of creation by pupils of an own educational product. Components of the subject information and education environment are presented: subject and target, substantial and organizational, estimated and reflexive components. The reformative and constructive tasks providing an activity orientation of the electronic textbook are considered.

Phase transitions in two-dimensional uniformly frustrated XY models. II. General scheme

International Nuclear Information System (INIS)

Korshunov, S.E.

1986-01-01

For two-dimensional uniformly frustrated XY models the group of symmetry spontaneously broken in the ground state is a cross product of the group of two-dimensional rotations by some discrete group of finite order. Different possibilities of phase transitions in such systems are investigated. The transition to the Coulomb gas with noninteger charges is widely used when analyzing the properties of relevant topological excitations. The number of these excitations includes not only domain walls and traditional (integer) vortices, but also vortices with a fractional number of circulation quanta which are to be localized at bends and intersections of domain walls. The types of possible phase transitions prove to be dependent on their relative sequence: in the case the vanishing of domain wall free energy occurs earlier (at increasing temperature) than the dissociation of pairs of ordinary vortices, the second phase transition is to be associated with dissociation of pairs of fractional vortices. The general statements are illustrated with a number of examples

Peace Values in Language Textbooks: The Case of "English for Ethiopia Student Textbook"

Science.gov (United States)

Gebregeorgis, Mehari Yimulaw

2017-01-01

Textbooks are not only meant to deliver subject knowledge; they are also a medium to convey universal and community-specific values. Aiming to explore the social and emotional development goals of "English for Ethiopia Student Textbook Grade 9," this study reviews the content and activities of the textbook by searching for embedded peace…

Raising European Citizens: Constructing European Identities in French and English Textbooks

Directory of Open Access Journals (Sweden)

Inari Sakki

2016-06-01

Full Text Available Schools play a pivotal role in the formation of identities and in the political socialization of youth. This study explores the social representations of European integration in French and English school textbooks and shows how the social representations are discursively used to construct national and European identities. By analysing the history and civics textbooks of major educational publishers, this study aims to demonstrate how European integration is understood, made familiar and concretized in the school textbooks of the two influential but different European countries. The findings suggest some shared and some diverse patterns in the way the two European countries portray and construct the political project of European integration. These representations, constructed around French Europe in French textbooks and ambivalent Europe in English textbooks, share the images of a strong European economy and a French-led political Europe. However, they position themselves differently with respect to the United States, motivation for the European unification process and the significance of common values and heritage. In both countries textbooks draw upon memories that are important for group identity. While the French textbooks make European integration meaningful in reference to a shared post-war collective memory and to a cultural memory based on a more ancient idea of Europe, shared values and heritage, the English textbooks anchor it more strongly to domestic policy.

Instructional Manuals of Boundary-Work : Psychology textbooks, student subjectivities, and disciplinary historiographies

NARCIS (Netherlands)

Flis, I.

2016-01-01

This article aims to provide an overview of the historiography of psychology textbooks. In the overview, I identify and describe in detail two strands of writing histories of introductory textbooks of psychology and juxtapose them to provide an integrated historiography of textbooks in psychology.

Two-dimensional multifractal cross-correlation analysis

International Nuclear Information System (INIS)

Xi, Caiping; Zhang, Shuning; Xiong, Gang; Zhao, Huichang; Yang, Yonghong

2017-01-01

Highlights: • We study the mathematical models of 2D-MFXPF, 2D-MFXDFA and 2D-MFXDMA. • Present the definition of the two-dimensional N 2 -partitioned multiplicative cascading process. • Do the comparative analysis of 2D-MC by 2D-MFXPF, 2D-MFXDFA and 2D-MFXDMA. • Provide a reference on the choice and parameter settings of these methods in practice. - Abstract: There are a number of situations in which several signals are simultaneously recorded in complex systems, which exhibit long-term power-law cross-correlations. This paper presents two-dimensional multifractal cross-correlation analysis based on the partition function (2D-MFXPF), two-dimensional multifractal cross-correlation analysis based on the detrended fluctuation analysis (2D-MFXDFA) and two-dimensional multifractal cross-correlation analysis based on the detrended moving average analysis (2D-MFXDMA). We apply these methods to pairs of two-dimensional multiplicative cascades (2D-MC) to do a comparative study. Then, we apply the two-dimensional multifractal cross-correlation analysis based on the detrended fluctuation analysis (2D-MFXDFA) to real images and unveil intriguing multifractality in the cross correlations of the material structures. At last, we give the main conclusions and provide a valuable reference on how to choose the multifractal algorithms in the potential applications in the field of SAR image classification and detection.

Two-dimensional beam profiles and one-dimensional projections

Science.gov (United States)

Findlay, D. J. S.; Jones, B.; Adams, D. J.

2018-05-01

One-dimensional projections of improved two-dimensional representations of transverse profiles of particle beams are proposed for fitting to data from harp-type monitors measuring beam profiles on particle accelerators. Composite distributions, with tails smoothly matched on to a central (inverted) parabola, are shown to give noticeably better fits than single gaussian and single parabolic distributions to data from harp-type beam profile monitors all along the proton beam transport lines to the two target stations on the ISIS Spallation Neutron Source. Some implications for inferring beam current densities on the beam axis are noted.

Education and Textbooks.

Science.gov (United States)

Simon, Josep; García-Belmar, Antonio

Education and textbooks have traditionally been standard objects of research in the history of science, technology, and medicine. However, they have often remained marginal in the formulation of large historiographical questions. In the last decades, the work of some historians of science has challenged this state of affairs. STEP has promoted a distinctive focus on education and textbooks, compared to other scholarship cultures such as the Anglo-American. This essay reviews its work in this field and stresses the potential of education and textbooks to produce interdisciplinary research in local, national, and international perspective.

An Analysis of the Readability of Financial Accounting Textbooks.

Science.gov (United States)

Smith, Gerald; And Others

1981-01-01

The Flesch formula was used to calculate the readability of 15 financial accounting textbooks. The 15 textbooks represented introductory, intermediate, and advanced levels and also were classified by five different publishers. Two-way analysis of variance and Tukey's post hoc analysis revealed some significant differences. (Author/CT)

FPGA Implementation of one-dimensional and two-dimensional cellular automata

International Nuclear Information System (INIS)

D'Antone, I.

1999-01-01

This report describes the hardware implementation of one-dimensional and two-dimensional cellular automata (CAs). After a general introduction to the cellular automata, we consider a one-dimensional CA used to implement pseudo-random techniques in built-in self test for VLSI. Due to the increase in digital ASIC complexity, testing is becoming one of the major costs in the VLSI production. The high electronics complexity, used in particle physics experiments, demands higher reliability than in the past time. General criterions are given to evaluate the feasibility of the circuit used for testing and some quantitative parameters are underlined to optimize the architecture of the cellular automaton. Furthermore, we propose a two-dimensional CA that performs a peak finding algorithm in a matrix of cells mapping a sub-region of a calorimeter. As in a two-dimensional filtering process, the peaks of the energy clusters are found in one evolution step. This CA belongs to Wolfram class II cellular automata. Some quantitative parameters are given to optimize the architecture of the cellular automaton implemented in a commercial field programmable gate array (FPGA)

Lie algebra contractions on two-dimensional hyperboloid

International Nuclear Information System (INIS)

Pogosyan, G. S.; Yakhno, A.

2010-01-01

The Inoenue-Wigner contraction from the SO(2, 1) group to the Euclidean E(2) and E(1, 1) group is used to relate the separation of variables in Laplace-Beltrami (Helmholtz) equations for the four corresponding two-dimensional homogeneous spaces: two-dimensional hyperboloids and two-dimensional Euclidean and pseudo-Euclidean spaces. We show how the nine systems of coordinates on the two-dimensional hyperboloids contracted to the four systems of coordinates on E 2 and eight on E 1,1 . The text was submitted by the authors in English.

Quasi-two-dimensional holography

International Nuclear Information System (INIS)

Kutzner, J.; Erhard, A.; Wuestenberg, H.; Zimpfer, J.

1980-01-01

The acoustical holography with numerical reconstruction by area scanning is memory- and time-intensive. With the experiences by the linear holography we tried to derive a scanning for the evaluating of the two-dimensional flaw-sizes. In most practical cases it is sufficient to determine the exact depth extension of a flaw, whereas the accuracy of the length extension is less critical. For this reason the applicability of the so-called quasi-two-dimensional holography is appropriate. The used sound field given by special probes is divergent in the inclined plane and light focussed in the perpendicular plane using cylindrical lenses. (orig.) [de

Genetic Counseling, Professional Values, and Habitus: An Analysis of Disability Narratives in Textbooks.

Science.gov (United States)

Reed, Amy R

2016-10-19

This article analyzes narrative illustrations in genetic counseling textbooks as a way of understanding professional habitus--the dispositions that motivate professional behavior. In particular, this analysis shows that there are significant differences in how the textbooks' expository and narrative portions represent Down syndrome, genetic counseling practice, and patient behaviors. While the narrative portions of the text position the genetic counseling profession as working in service to the values of genetic medicine, the expository portions represent genetic counselors as neutral parties. Ultimately, this article argues that this ambiguity is harmful to the production of a professional habitus that is consistent with espoused professional values concerning respect for persons with disabilities and the promotion of psychosocial counseling.

Complex Text in ESL Grammar Textbooks: Barriers or Gateways?

Science.gov (United States)

Lesikin, Joan

2000-01-01

Suggests that English-as-a-Second-Language (ESL) teachers assess prospective textbooks by comparing real-life user's actual knowledge of the author's assumed student knowledge. Through examination of charts and page excerpts of two ESL grammar textbooks, demonstrates that access to the pedagogical knowledge demands sophisticated formal knowledge,…

Topology optimization of two-dimensional waveguides

DEFF Research Database (Denmark)

Jensen, Jakob Søndergaard; Sigmund, Ole

2003-01-01

In this work we use the method of topology optimization to design two-dimensional waveguides with low transmission loss.......In this work we use the method of topology optimization to design two-dimensional waveguides with low transmission loss....

Traditional Semiconductors in the Two-Dimensional Limit.

Science.gov (United States)

Lucking, Michael C; Xie, Weiyu; Choe, Duk-Hyun; West, Damien; Lu, Toh-Ming; Zhang, S B

2018-02-23

Interest in two-dimensional materials has exploded in recent years. Not only are they studied due to their novel electronic properties, such as the emergent Dirac fermion in graphene, but also as a new paradigm in which stacking layers of distinct two-dimensional materials may enable different functionality or devices. Here, through first-principles theory, we reveal a large new class of two-dimensional materials which are derived from traditional III-V, II-VI, and I-VII semiconductors. It is found that in the ultrathin limit the great majority of traditional binary semiconductors studied (a series of 28 semiconductors) are not only kinetically stable in a two-dimensional double layer honeycomb structure, but more energetically stable than the truncated wurtzite or zinc-blende structures associated with three dimensional bulk. These findings both greatly increase the landscape of two-dimensional materials and also demonstrate that in the double layer honeycomb form, even ordinary semiconductors, such as GaAs, can exhibit exotic topological properties.

Making an Interactive Calculus Textbook.

Science.gov (United States)

Larson, Timothy R.

1995-01-01

Presents a case study of the design and production of "Interactive Calculus," an interactive multimedia textbook. Discusses reasons for using multimedia textbooks; what an interactive textbook is; content, organization, graphic design, authoring and composition; and work flow. (AEF)

On the Market for Principles of Economics Textbooks: Innovation and Product Differentiation.

Science.gov (United States)

Stiglitz, Joseph E.

1988-01-01

Discusses the problems presented by current principles of economics textbooks, proposing two theses: that the market for principles textbooks is one of monopolistic competition, and that it reflects certain market failures. Examines changes that are needed so that textbooks will reflect more adequately important changes in the economy and economic…

A two-dimensional mathematical model of percutaneous drug absorption

Directory of Open Access Journals (Sweden)

Kubota K

2004-06-01

Full Text Available Abstract Background When a drug is applied on the skin surface, the concentration of the drug accumulated in the skin and the amount of the drug eliminated into the blood vessel depend on the value of a parameter, r. The values of r depend on the amount of diffusion and the normalized skin-capillary clearence. It is defined as the ratio of the steady-state drug concentration at the skin-capillary boundary to that at the skin-surface in one-dimensional models. The present paper studies the effect of the parameter values, when the region of contact of the skin with the drug, is a line segment on the skin surface. Methods Though a simple one-dimensional model is often useful to describe percutaneous drug absorption, it may be better represented by multi-dimensional models. A two-dimensional mathematical model is developed for percutaneous absorption of a drug, which may be used when the diffusion of the drug in the direction parallel to the skin surface must be examined, as well as in the direction into the skin, examined in one-dimensional models. This model consists of a linear second-order parabolic equation with appropriate initial conditions and boundary conditions. These boundary conditions are of Dirichlet type, Neumann type or Robin type. A finite-difference method which maintains second-order accuracy in space along the boundary, is developed to solve the parabolic equation. Extrapolation in time is applied to improve the accuracy in time. Solution of the parabolic equation gives the concentration of the drug in the skin at a given time. Results Simulation of the numerical methods described is carried out with various values of the parameter r. The illustrations are given in the form of figures. Conclusion Based on the values of r, conclusions are drawn about (1 the flow rate of the drug, (2 the flux and the cumulative amount of drug eliminated into the receptor cell, (3 the steady-state value of the flux, (4 the time to reach the steady

Trickle-down evolution: an approach to getting major evolutionary adaptive changes into textbooks and curricula.

Science.gov (United States)

Padian, Kevin

2008-08-01

Although contemporary high school and college textbooks of biology generally cover the principles and data of microevolution (genetic and populational change) and speciation rather well, coverage of what is known of the major changes in evolution (macroevolution), and how the evidence is understood is generally poor to nonexistent. It is critical to improve this because acceptance of evolution by the American public rests on the understanding of how we know what we know about the emergence of major new taxonomic groups, and about their adaptations, behaviors, and ecologies in geologic time. An efficient approach to this problem is to improve the illustrations in college textbooks to show the consilience of different lines of fossil, morphological, and molecular evidence mapped on phylogenies. Such "evograms" will markedly improve traditional illustrations of phylogenies, "menageries," and "companatomies." If "evograms" are installed at the college level, the basic principles and evidence of macroevolution will be more likely taught in K-12, thus providing an essential missing piece in biological education.

Results of a Textbook Survey Given in Introductory Astronomy

Science.gov (United States)

Willoughby, Shannon

2007-05-01

Textbooks are required for virtually all college science courses taught around the country, but whether students use them and find them valuable is not clear. In order to get a better idea about what the students thought of the textbook and how they spent their time using it, an anonymous survey was taken by 305 (out of 400) students enrolled in Physics 101 during the Fall semester of 2005. Developed and administered by www.textrev.com, this is a free survey that college faculty may use for physics and chemistry textbooks. This survey revealed two interesting points. First, although 75% of the students found the textbook to be moderately to very challenging, only 38% of students reported spending 2 or more hours per week reading the text. Reading was assigned the majority of class periods, with the intention that they would read the material before it was covered in class. Second, 81% of the students found that the end of chapter problems were moderately to very challenging, but 62% reported spending one hour or less per week working on the assigned questions. Homework was assigned regularly from the textbook for the first half of the class, after which point we experimented with an online homework system. Next semester a new textbook is being adopted for this class, which has no color pictures and is significantly slimmer than the current textbook. This textbook survey will be given again at the end of next semester to look for any changes in textbook usage.

Gender stereotyping in EFL grammar textbooks. A diachronic approach

Directory of Open Access Journals (Sweden)

Marcin Lewandowski

2014-12-01

Full Text Available Gender stereotyping in educational materials (especially in EFL textbooks has been a common theme in linguistic research (cf., e. g., Hellinger 1980; Porreca 1984; Freebody/Baker 1987; Sunderland 1994; Lee/Collins 2010. However, very little attention has been paid to the representation of men and women in EFL/ESL grammar textbooks; i. e. the way both genders are portrayed in constructed examples of usage and practice sentences. The present contribution is intended to fill this gap. The paper investigates the scope of gender stereotyping from a diachronic perspective: it seeks to demonstrate whether and how the images of men and women have changed following the dissemination of guidelines for non-sexist language and equal treatment of the two genders in English language educational materials. To this aim, two corpora have been compiled. The first one includes sentences derived from three EFL textbooks published in the 1970s and 1980s, while the other one contains analogous data from three 21st century titles. The contrastive analysis of the sentences in the two corpora across 11 semantic domains has found that the recently published grammar textbooks portray the two genders in a much less stereotyped way than the 20th century course books.

Two-dimensional flexible nanoelectronics

Science.gov (United States)

Akinwande, Deji; Petrone, Nicholas; Hone, James

2014-12-01

2014/2015 represents the tenth anniversary of modern graphene research. Over this decade, graphene has proven to be attractive for thin-film transistors owing to its remarkable electronic, optical, mechanical and thermal properties. Even its major drawback--zero bandgap--has resulted in something positive: a resurgence of interest in two-dimensional semiconductors, such as dichalcogenides and buckled nanomaterials with sizeable bandgaps. With the discovery of hexagonal boron nitride as an ideal dielectric, the materials are now in place to advance integrated flexible nanoelectronics, which uniquely take advantage of the unmatched portfolio of properties of two-dimensional crystals, beyond the capability of conventional thin films for ubiquitous flexible systems.

Historical Evolution of the Field View and Textbook Accounts.

Science.gov (United States)

Pocovi, M. Cecilia; Finley, Fred N.

2003-01-01

Analyzes how two electromagnetism textbooks approach the concept of electric field. Uses historical evolution of the field representation. Indicates that one textbook mixes up the historical and pedagogical reasons for the introduction of the concept of field while the other one presents a sketch that might lead students to understand the field…

ANALYSIS OF THE APPROACH TO THE ATLANTIC FOREST IN HIGH SCHOOL BIOLOGY TEXTBOOKS

Directory of Open Access Journals (Sweden)

Nicácio Oliveira Freitas

2017-03-01

Full Text Available The textbooks are the main teaching tool for students and teachers. The analysis of these books enables point out several shortcomings in relation to the contents approach. Thus, the objective of this work was to analyze the approach to the Atlantic Forest, considered one of the most degraded environments of the world. A total of seven high school biology textbooks were analyzed, following an evaluation script with general information, biotic and abiotic factors, environmental conservation and anthropic action, which were considered as satisfactory or unsatisfactory in the textbooks evaluation. In general, the Atlantic Forest theme has been addressed by all assessed books, including specific topics, however, some aspects such as the use of images was made improperly, leading to misunderstandings about Atlantic forest. In addition, ecosystem dynamics, its components and the environmental impacts have not been addressed satisfactorily in the majority of the works assessed. In general, the theme Atlantic Forest has been addressed by all assessed books, including specific topics, however, many aspects of this theme presented problems in their approach: update, concepts, definitions and importance, and also presented problems in their illustration of the current situation of Atlantic Forest. Periodic revisions of these textbooks are of great importance to assure student formation that allows them to analyze and know the effects of their actions on the environment and to reflect on ways to alleviates them. Keywords: biology textbooks; ecosystem; contents analysis.

History of science content analysis of Chinese science textbooks from the perspective of acculturation

Science.gov (United States)

Ma, Yongjun; Wan, Yanlan

2017-08-01

Based on previous international studies, a content analysis scheme has been designed and used from the perspective of culture to study the history of science (HOS) in science textbooks. Nineteen sets of Chinese science textbooks have been analyzed. It has been found that there are noticeable changes in the quantity, content, layout, presentation, and writing intention of the HOS sections in textbooks from different time periods. What's more, the textbooks aim at presenting the scientific culture and aim to help students understand it better. However, the cultural associations of the HOS in textbooks is insufficient and significant differences exist among textbooks of different subjects. In order to explore the reasons why the presentation of HOS in various subjects is different, we made a specific comparison of curriculum standards of two subjects with great differences and interviewed the editors-in-chief of two textbooks. Results show that one of the most important reasons for the different writings of the HOS in textbooks is that different subject curriculum standards attach greater importance to the HOS. In addition, the attention to the HOS by editors-in-chief, the tradition of studying the HOS within the history of the discipline, and the reference textbooks in compiling textbooks are all important influence factors. Some suggestions for future textbooks compilation are given at the end.

Potential benefits of student- and junior doctor-led textbooks.

Science.gov (United States)

Qureshi, Zeshan U; Lattey, Katherine; Bryne, Patrick; Rodrigues, Mark; Ross, Michael; Maxwell, Simon

2015-06-01

Medical textbooks are an important teaching supplement. Few have junior doctors or medical students ('juniors') as primary contributors. However, the strengths of junior-led face-to-face teaching are now well-established, and we hypothesized that similar advantages would be transferrable to a textbook setting. Juniors were approached to contribute to an independently published medical textbook, with senior clinicians recruited in parallel to ensure factual accuracy. Juniors directed every aspect of textbook writing and the production process. The published book stressed that it was an open collaboration with readers, inviting them to get in touch to evaluate the text and suggest ideas for new titles. Of 75 respondents, 93 % awarded the first textbook in the series 4 or 5 out of 5 for overall quality. Five other titles have been released, with seven more in development. Over 100 juniors are currently involved, with two students progressing from reviewers to editors after less than a year of mentorship. Juniors can be a motivated, dynamic, innovative group, capable of significant contributions to the medical textbook literature. This initiative has generated a sustainable infrastructure to facilitate junior-led publishing, and has the capacity for expansion to accommodate new initiatives and ideas.

Quantum transport of atomic matter waves in anisotropic two-dimensional and three-dimensional disorder

International Nuclear Information System (INIS)

Piraud, M; Pezzé, L; Sanchez-Palencia, L

2013-01-01

The macroscopic transport properties in a disordered potential, namely diffusion and weak/strong localization, closely depend on the microscopic and statistical properties of the disorder itself. This dependence is rich in counter-intuitive consequences. It can be particularly exploited in matter wave experiments, where the disordered potential can be tailored and controlled, and anisotropies are naturally present. In this work, we apply a perturbative microscopic transport theory and the self-consistent theory of Anderson localization to study the transport properties of ultracold atoms in anisotropic two-dimensional (2D) and three-dimensional (3D) speckle potentials. In particular, we discuss the anisotropy of single-scattering, diffusion and localization. We also calculate disorder-induced shift of the energy states and propose a method to include it, which amounts to renormalizing energies in the standard on-shell approximation. We show that the renormalization of energies strongly affects the prediction for the 3D localization threshold (mobility edge). We illustrate the theoretical findings with examples which are relevant for current matter wave experiments, where the disorder is created with laser speckle. This paper provides a guideline for future experiments aiming at the precise location of the 3D mobility edge and study of anisotropic diffusion and localization effects in 2D and 3D. (paper)

Assembly of positioner of automated two-dimensional scan coupled to X-ray fluorescence spectrometry

International Nuclear Information System (INIS)

Silva, Leonardo Santiago Melgaço

2011-01-01

This work describes the design and assembling of a prototype automated positioner two-dimensional scanning coupled to X-ray fluorescence spectrometry. The work aims to achieve a portable and easy to use, device of broad utility in the analysis of samples by X-ray fluorescence area of expertise and research. The two-dimensional scanning of the positioner is by means of two stepper motors controlled by a microcontroller PIC 16F877A, encoder and optical sensors. The user interacts with the XY table through an interface program for the Windows operating system, which communicates with the microcontroller through the serial port. The system of Fluorescence Spectroscopy incorporated into the positioner consists of a system commercially available system from the company AMPTEK, where the primary source of excitation of the sample was a source of 241 Am of 59.5 KeV emissions. Resolution and accuracy of tests were performed in the XY scanning process and reproducibility of the same kit with the fluorescence spectrometry X-ray. Qualitative tests by X-ray fluorescence spectrometry in samples were performed to demonstrate the applicability and versatility of the project. It follows that the prototype illustrates a possible adequately to portable device for X-ray spectrometry of two-dimensional. (author)

Physical Environment as a 3-D Textbook: Design and Development of a Prototype

Science.gov (United States)

Kong, Seng Yeap; Yaacob, Naziaty Mohd; Ariffin, Ati Rosemary Mohd

2015-01-01

The use of the physical environment as a three-dimensional (3-D) textbook is not a common practice in educational facilities design. Previous researches documented that little progress has been made to incorporate environmental education (EE) into architecture, especially among the conventional designers who are often constrained by the budget and…

Two-dimensional differential transform method for solving linear and non-linear Schroedinger equations

International Nuclear Information System (INIS)

Ravi Kanth, A.S.V.; Aruna, K.

2009-01-01

In this paper, we propose a reliable algorithm to develop exact and approximate solutions for the linear and nonlinear Schroedinger equations. The approach rest mainly on two-dimensional differential transform method which is one of the approximate methods. The method can easily be applied to many linear and nonlinear problems and is capable of reducing the size of computational work. Exact solutions can also be achieved by the known forms of the series solutions. Several illustrative examples are given to demonstrate the effectiveness of the present method.

Students' Intentions to Purchase Electronic Textbooks

Science.gov (United States)

Stone, Robert W.; Baker-Eveleth, Lori J.

2013-01-01

Textbooks have played an important role in education for decades. Given the significant number of technology applications in education, it is not surprising that at least one such application is the electronic textbook (e-textbook). There are a variety of motivations to adopt an e-textbook, including frequent content updates and low costs. The…

Teachers' preferences towards textbook

Directory of Open Access Journals (Sweden)

Stanojević Darko D.

2016-01-01

Full Text Available In this paper, using the method named Conjoint analysis, and with the goal of determining teacher's preferences in the process of textbook selection, and also defining the prototype of quality textbook which will could be used in the classroom. With consideration of criteria defined in the previous researches on this topic, an continuing the work on those results, we will create clear hypothetical prototype of the textbook which will satisfy the teacher's preference.

Two-dimensional topological field theories coupled to four-dimensional BF theory

International Nuclear Information System (INIS)

Montesinos, Merced; Perez, Alejandro

2008-01-01

Four-dimensional BF theory admits a natural coupling to extended sources supported on two-dimensional surfaces or string world sheets. Solutions of the theory are in one to one correspondence with solutions of Einstein equations with distributional matter (cosmic strings). We study new (topological field) theories that can be constructed by adding extra degrees of freedom to the two-dimensional world sheet. We show how two-dimensional Yang-Mills degrees of freedom can be added on the world sheet, producing in this way, an interactive (topological) theory of Yang-Mills fields with BF fields in four dimensions. We also show how a world sheet tetrad can be naturally added. As in the previous case the set of solutions of these theories are contained in the set of solutions of Einstein's equations if one allows distributional matter supported on two-dimensional surfaces. These theories are argued to be exactly quantizable. In the context of quantum gravity, one important motivation to study these models is to explore the possibility of constructing a background-independent quantum field theory where local degrees of freedom at low energies arise from global topological (world sheet) degrees of freedom at the fundamental level

Image of the Ottomans in Bosnian Textbooks Published After 2007

Directory of Open Access Journals (Sweden)

Jahja Muhasilović

2015-01-01

Full Text Available Division of historical consciousness in Bosnia and Herzegovina started before the Yugoslav Wars, but this division of historiographies and approaches towards the past resulted with more openly manifestation of the divisions to educational system and history textbooks during the wartime and post Dayton era. Even though International Community tried to change poisonous environment of ethnic hatred in which textbooks are produced, except few successes with Bosniak textbooks, not much positive development was achieved. Reform period which started in 1998 today is seen as an unfinished project. In Bosnia and Herzegovina three different versions of history with two of them having the focus point in neighboring Serbia and Croatia are taught to the students. Besides the fact that students are learning three different histories, there is a certain level of hatred and fear of others spreading through history textbooks. History textbooks became an important tool for poisoning the minds of the youth and building the barriers towards the others. This is the case especially with Serb and Croat textbooks in Bosnia and Herzegovina. Ottoman period in Balkans is mainly seen as a ‘’dark age of the Balkans’’ as it is underlined in one Serbian textbook and to lesser extend in Croat ones. Even though Bosniaks see Ottoman period in more positive light than other two ethnic groups, there are certain topics and periods were it is possible to see romantistic and nationalistic tone towards the Ottomans. History textbooks in Bosnia are having negative contribution for country’s possible future dissolution and it is the one of the main source of stereotype engineering that country is passing in the last decades and which is one of the main reason of the recent wars. In the times where country is confronting with secessionist threat, it is highly important to start building Bosnian statehood and understanding of others through history textbooks, otherwise we can

An Evaluation of Grades 9 and 10 Mathematics Textbooks Vis-À-Vis ...

African Journals Online (AJOL)

An Evaluation of Grades 9 and 10 Mathematics Textbooks Vis-À-Vis Fostering Problem Solving Skills. ... Document analysis was carried out on the two textbooks using Mathematics Material Analysis Instrument (MMAI) developed by Karen (1997). Interview was held with two experts from Institute of Curriculum Development ...

Scholarship, Textbooks, and Mythology

Science.gov (United States)

Noell, Laura K.

2004-01-01

A new textbook designed for first- or second-year courses in mythology as an introduction to literature shows that a community college faculty member who writes a textbook adds teaching experience to scholarship.

Two-dimensional x-ray diffraction

CERN Document Server

He, Bob B

2009-01-01

Written by one of the pioneers of 2D X-Ray Diffraction, this useful guide covers the fundamentals, experimental methods and applications of two-dimensional x-ray diffraction, including geometry convention, x-ray source and optics, two-dimensional detectors, diffraction data interpretation, and configurations for various applications, such as phase identification, texture, stress, microstructure analysis, crystallinity, thin film analysis and combinatorial screening. Experimental examples in materials research, pharmaceuticals, and forensics are also given. This presents a key resource to resea

Dimensionality and Its Effect on Retention and Visual Scanning.

Science.gov (United States)

Abed, Farough

1994-01-01

Describes a study of eighth graders that compared the effects of two-dimensional and three-dimensional illustrated texts on eye movement strategies and on retention of information. Results are reported that support earlier research findings that realism in illustrations is not necessarily facilitating and may even be distracting. (Contains 19…

[Joint contractures in nursing textbooks].

Science.gov (United States)

Bartoszek, G; Meyer, G; Thiesemann, R

2014-01-01

The transparency criteria of the German statutory health insurance on joint contracture prevention have led to controversies about the appropriate assessment, prevention and treatment as well as to various actions in nursing practice. However, appropriate nursing assessments and proven treatment options are lacking so far. It is unclear whether textbooks on nursing reflect these uncertainties. Search for textbooks on nursing through internet-based search engines and publisher registers, data extraction by one investigator and control by a second. A total of 35 textbooks with contributions on joint contractures were identified of which 25 included a definition, causes/risk factors are presented in 32 textbooks and assessments are presented in 5 books. Most often positioning into a physiological or functional neutral position and passive moving of limbs are recommended as passive prophylaxis. Recommended therapeutic and preventive options do not differ. None of the textbooks reflect that there is a lack of scientific knowledge on the subject. Textbooks on nursing do not deal with complete and scientific sound information on joint contractures.

Dynamics of lava flow - Thickness growth characteristics of steady two-dimensional flow

Science.gov (United States)

Park, S.; Iversen, J. D.

1984-01-01

The thickness growth characteristics of flowing lava are investigated using a heat balance model and a two-dimensional model for flow of a Bingham plastic fluid down an inclined plane. It is found that yield strength plays a crucial role in the thickening of a lava flow of given flow rate. To illustrate this point, downstream thickness profiles and yield strength distributions were calculated for flows with mass flow rates of 10,000 and 100,000 kg/m-sec. Higher flow rates led to slow cooling rates which resulted in slow rate of increase of yield strength and thus greater flow lengths.

Piezoelectricity in Two-Dimensional Materials

KAUST Repository

Wu, Tao

2015-02-25

Powering up 2D materials: Recent experimental studies confirmed the existence of piezoelectricity - the conversion of mechanical stress into electricity - in two-dimensional single-layer MoS2 nanosheets. The results represent a milestone towards embedding low-dimensional materials into future disruptive technologies. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA.

Teachers' selection and enactment of mathematical problems from textbooks

Science.gov (United States)

Son, Ji-Won; Kim, Ok-Kyeong

2015-12-01

In order to investigate how teachers' use of textbooks creates different kinds of opportunities for student learning, this study focused on teachers' selection and enactment of problems and tasks from the textbooks and their influence on the cognitive demand placed on students. By drawing on data from three elementary teachers in the USA, two of which used a reform-oriented textbook— Math Trailblazers and one a commercially developed textbook—this study examined kinds of problems the teachers chose and ways in which they enacted those problems in relation to the cognitive demand of the problems. In particular, we attended to the kinds of questions the teachers asked in enacting the problems and ways in which those questions influenced the cognitive demand of the textbook problems. This study also identified critical issues involved in teacher decision-making on task selection and enactment, such as the match between teachers' goals and those of the textbooks, and teachers' perception of textbook problems. Based on the results of the study, we discuss implications for teacher education and professional development.

Orbits of the n-dimensional Kepler-Coulomb problem and universality of the Kepler laws

International Nuclear Information System (INIS)

Oender, M; Vercin, A

2006-01-01

In the standard classical mechanics textbooks used at undergraduate and graduate levels, no attention is paid to the dimensional aspects of the Kepler-Coulomb problem. We have shown that the orbits of the n-dimensional classical Kepler-Coulomb problem are the usual conic sections in a fixed two-dimensional subspace and the Kepler laws with their well-known forms are valid independent of dimension. The basic characteristics of motion in a central force field are also established in an arbitrary dimension. The approach followed is easily accessible to late undergraduate and recent graduate students

Naïve conceptions about multimedia learning: a study on primary school textbooks.

Science.gov (United States)

Colombo, Barbara; Antonietti, Alessandro

2013-01-01

HIGHLIGHTSThis interview study explores beliefs about the instructional role of illustrationsWe compared illustrators', teachers', students' and common people's ideasParticipants' responses were internally coherent and close to multimedia learning theoryWe propose and discuss an integrated multimedia learning model An interview study, based on specific pictures taken from textbooks used in primary schools, was carried out to investigate illustrators', teachers', students', and common people's beliefs about the role that illustrations play in facilitating learning. Participants' responses were internally coherent, indicating a systematic nature of the underlying naïve conceptions. Findings disprove Mayer's pessimistic claim that laypersons' conceptions of multimedia learning fail to match experimentally supported principles and theories. On the contrary, interviewees spontaneously came very close to the multimedia learning theory, which states that students learn better from pictures, which fit specific cognitive principles. Implications for school instruction are highlighted.

From Fertilization to Birth: Representing Development in High School Biology Textbooks

Science.gov (United States)

Wellner, Karen L.

Biology textbooks are everybody's business. In accepting the view that texts are created with specific social goals in mind, I examined 127 twentieth-century high school biology textbooks for representations of animal development. Paragraphs and visual representations were coded and placed in one of four scientific literacy categories: descriptive, investigative, nature of science, and human embryos, technology, and society (HETS). I then interpreted how embryos and fetuses have been socially constructed for students. I also examined the use of Haeckel's embryo drawings to support recapitulation and evolutionary theory. Textbooks revealed that publication of Haeckel's drawings was influenced by evolutionists and anti-evolutionists in the 1930s, 1960s, and the 1990s. Haeckel's embryos continue to persist in textbooks because they "safely" illustrate similarities between embryos and are rarely discussed in enough detail to understand comparative embryology's role in the support of evolution. Certain events coincided with changes in how embryos were presented: (a) the growth of the American Medical Association (AMA) and an increase in birth rates (1950s); (b) the Biological Sciences Curriculum Study (BSCS) and public acceptance of birth control methods (1960s); (c) Roe vs. Wade (1973); (d) in vitro fertilization and Lennart Nilsson's photographs (1970s); (e) prenatal technology and fetocentrism (1980s); and (f) genetic engineering and Science-Technology-Society (STS) curriculum (1980s and 1990s). By the end of the twentieth century, changing conceptions, research practices, and technologies all combined to transform the nature of biological development. Human embryos went from a highly descriptive, static, and private object to that of sometimes contentious public figure. I contend that an ignored source for helping move embryos into the public realm is schoolbooks. Throughout the 1900s, authors and publishers accomplished this by placing biology textbook embryos and

An Analytical Evaluation of Iranian High School ELT Textbooks from 1970 to 2010

Directory of Open Access Journals (Sweden)

Akbar Azizifar

2009-10-01

Full Text Available Textbooks play a very crucial role in the process of language teaching and learning. The present study carries out an evaluation of two series of ELT textbooks used for teaching English language in Iranian high schools since 1970 to 2010. For this purpose, Tucker’s (1975 textbook evaluation model (see Appendix has been employed. The results suggest that one of the main factors for the students’ achievement in English language is the ELT textbooks. The researcher suggests that in the textbooks, there should be enough opportunity for the learners to communicatively practice the language they are learning.

Two-dimensional confinement of heavy fermions

International Nuclear Information System (INIS)

Shishido, Hiroaki; Shibauchi, Takasada; Matsuda, Yuji; Terashima, Takahito

2010-01-01

Metallic systems with the strongest electron correlations are realized in certain rare-earth and actinide compounds whose physics are dominated by f-electrons. These materials are known as heavy fermions, so called because the effective mass of the conduction electrons is enhanced via correlation effects up to as much as several hundreds times the free electron mass. To date the electronic structure of all heavy-fermion compounds is essentially three-dimensional. Here we report on the first realization of a two-dimensional heavy-fermion system, where the dimensionality is adjusted in a controllable fashion by fabricating heterostructures using molecular beam epitaxy. The two-dimensional heavy fermion system displays striking deviations from the standard Fermi liquid low-temperature electronic properties. (author)

Migrations in Slovenian geography textbooks

Directory of Open Access Journals (Sweden)

Jurij Senegačnik

2013-12-01

Full Text Available In Slovenia, the migrations are treated in almost all geographical textbooks for different levels of education. In the textbooks for the elementary school from the sixth to ninth grade, students acquire knowledge of the migrations by the inductive approach. Difficulty level of treatment and quantity of information are increasing by the age level. In the grammar school program a trail of gaining knowledge on migration is deductive. Most attention is dedicated to migrations in general geography textbooks. The textbooks for vocational and technical school programs deal with migrations to a lesser extent and with different approaches.

Provocative Opinion: Elephantiasis of the Textbook.

Science.gov (United States)

Kerber, Robert C.

1988-01-01

Addresses the growing size of college organic chemistry textbooks. Notes that at the current rate of growth, average textbooks will be 1544 pages long in year 2000. Suggests methods to reduce textbook size. (ML)

Inside France: Three Missing Pages from Your Students' Textbook.

Science.gov (United States)

Conniffe, Patricia, Ed.

This mini-unit seeks to fill the gap in textbooks that exists when teaching about modern France. Many textbooks end their coverage of France with the chapter on World War II. This unit offers high school students a unique introduction to France in the mid-1990s. The mini-unit includes a two-sided poster, teaching tips, and student pages. Student…

Two-dimensional topological photonics

Science.gov (United States)

Khanikaev, Alexander B.; Shvets, Gennady

2017-12-01

Originating from the studies of two-dimensional condensed-matter states, the concept of topological order has recently been expanded to other fields of physics and engineering, particularly optics and photonics. Topological photonic structures have already overturned some of the traditional views on wave propagation and manipulation. The application of topological concepts to guided wave propagation has enabled novel photonic devices, such as reflection-free sharply bent waveguides, robust delay lines, spin-polarized switches and non-reciprocal devices. Discrete degrees of freedom, widely used in condensed-matter physics, such as spin and valley, are now entering the realm of photonics. In this Review, we summarize the latest advances in this highly dynamic field, with special emphasis on the experimental work on two-dimensional photonic topological structures.

Structures of two-dimensional three-body systems

International Nuclear Information System (INIS)

Ruan, W.Y.; Liu, Y.Y.; Bao, C.G.

1996-01-01

Features of the structure of L = 0 states of a two-dimensional three-body model system have been investigated. Three types of permutation symmetry of the spatial part, namely symmetric, antisymmetric, and mixed, have been considered. A comparison has been made between the two-dimensional system and the corresponding three-dimensional one. The effect of symmetry on microscopic structures is emphasized. (author)

The place of surface anatomy in the medical literature and undergraduate anatomy textbooks.

Science.gov (United States)

Azer, Samy A

2013-01-01

The aims of this review were to examine the place of surface anatomy in the medical literature, particularly the methods and approaches used in teaching surface and living anatomy and assess commonly used anatomy textbooks in regard to their surface anatomy contents. PubMed and MEDLINE databases were searched using the following keywords "surface anatomy," "living anatomy," "teaching surface anatomy," "bony landmarks," "peer examination" and "dermatomes". The percentage of pages covering surface anatomy in each textbook was calculated as well as the number of images covering surface anatomy. Clarity, quality and adequacy of surface anatomy contents was also examined. The search identified 22 research papers addressing methods used in teaching surface anatomy, 31 papers that can help in the improvement of surface anatomy curriculum, and 12 anatomy textbooks. These teaching methods included: body painting, peer volunteer surface anatomy, use of a living anatomy model, real time ultrasound, virtual (visible) human dissector (VHD), full body digital x-ray of cadavers (Lodox(®) Statscan(®) images) combined with palpating landmarks on peers and the cadaver, as well as the use of collaborative, contextual and self-directed learning. Nineteen of these studies were published in the period from 2006 to 2013. The 31 papers covered evidence-based and clinically-applied surface anatomy. The percentage of surface anatomy in textbooks' contents ranged from 0 to 6.2 with an average of 3.4%. The number of medical illustrations on surface anatomy varied from 0 to 135. In conclusion, although there has been a progressive increase in publications addressing methods used in teaching surface anatomy over the last six to seven years, most anatomy textbooks do not provide students with adequate information about surface anatomy. Only three textbooks provided a solid explanation and foundation of understanding surface anatomy. © 2013 American Association of Anatomists.

Retrotext- E 1.0: The Beginnings of Computer-based ELT Textbook Evaluation

Directory of Open Access Journals (Sweden)

Jayakaran Mukundan

2010-07-01

Full Text Available There are two main reasons why textbooks are evaluated; the first which is associated to the task of textbook selection (predictive evaluation and the second to the need to evaluate it while in use (retrospective evaluation so that teachers can implement adaptation procedures later. Predictive evaluation is almost nonexistent in most developing countries as textbooks are usually provided free or through a textbook loan scheme. There is however hope for getting teachers involved in while-use/post use or retrospective evaluation of textbooks as they no only help teachers with adaptation but help teachers in their overall professional development. Since textbooks are an essential part of the teacher’s professional  life any form of out-of-class work that involves the teacher’s own knowledge building can become an integral part of the teacher’s professional development.

X-ray imaging device for one-dimensional and two-dimensional radioscopy

International Nuclear Information System (INIS)

1978-01-01

The X-ray imaging device for the selectable one-dimensional or two-dimensional pictures of objects illuminated by X-rays, comprising an X-ray source, an X-ray screen, and an opto-electrical picture development device placed behind the screen, is characterized by an anamorphotic optical system, which is positioned with a one-dimensional illumination between the X-ray screen and the opto-electrical device and that a two-dimensional illumination will be developed, and that in view of the lens system which forms part of the opto-electrical device, there is placed an X-ray screen in a specified beam direction so that a magnified image may be formed by equalisation of the distance between the X-ray screen and the lens system. (G.C.)

Hamiltonian formalism of two-dimensional Vlasov kinetic equation.

Science.gov (United States)

Pavlov, Maxim V

2014-12-08

In this paper, the two-dimensional Benney system describing long wave propagation of a finite depth fluid motion and the multi-dimensional Russo-Smereka kinetic equation describing a bubbly flow are considered. The Hamiltonian approach established by J. Gibbons for the one-dimensional Vlasov kinetic equation is extended to a multi-dimensional case. A local Hamiltonian structure associated with the hydrodynamic lattice of moments derived by D. J. Benney is constructed. A relationship between this hydrodynamic lattice of moments and the two-dimensional Vlasov kinetic equation is found. In the two-dimensional case, a Hamiltonian hydrodynamic lattice for the Russo-Smereka kinetic model is constructed. Simple hydrodynamic reductions are presented.

Evaluation Study for Secondary Stage EFL Textbook: EFL Teachers' Perspectives

Science.gov (United States)

Al Harbi, Abdullah Abdul Muhsen

2017-01-01

This study aimed at evaluating EFL textbook for secondary stage in Saudi Public schools. Participants consisted of (100) male teachers and (73) female teachers teaching secondary stage students in two cities: Madinah and Dowadmi. The tool of the study designed to cover five dimensions: layout and design, the objectives of the textbook, teaching…

Core References in Introductory Social Psychology and Developmental Psychology Textbooks

Science.gov (United States)

Whitehead, George I., III; Smith, Stephanie H.; Losonczy-Marshall, Marta

2017-01-01

The purpose of the present study was to identify the core references in introductory textbooks in two sub-disciplines of psychology: social psychology and developmental psychology. One research question was the extent to which the common references in these textbooks present the trends in contemporary research in each sub-discipline. An analysis…

Novel target design algorithm for two-dimensional optical storage (TwoDOS)

NARCIS (Netherlands)

Huang, Li; Chong, T.C.; Vijaya Kumar, B.V.K.; Kobori, H.

2004-01-01

In this paper we introduce the Hankel transform based channel model of Two-Dimensional Optical Storage (TwoDOS) system. Based on this model, the two-dimensional (2D) minimum mean-square error (MMSE) equalizer has been derived and applied to some simple but common cases. The performance of the 2D

Novel two-dimensional uranyl-organic assemblages in the citrate and D(-)-citramalate families

International Nuclear Information System (INIS)

Thuery, P.

2008-01-01

Uranyl nitrate reacts with D(-)-citramalic acid (H(3)citml) under mild hydrothermal conditions to give the two-dimensional polymer [UO 2 (Hcitml)] 1, in which each ligand chelates one metal atom through its hydroxyl and alpha- carboxylate groups and binds to three others in monodentate fashion. The resulting neutral layers display isolated uranyl pentagonal bipyramidal polyhedra. Whereas citric acid (H(4)cit) has been shown previously to give various three- and mono-dimensional uranyl organic assemblages, complexation under hydrothermal conditions in the presence of either NaOH/NEt 4 Cl or pyridine yields the complexes [NEt 4 ] 2 [(UO 2 ) 3 (cit) 2 (H 2 O) 2 ]· 2H 2 O 2 and [Hpy] 2 )[(UO 2 ) 3 (cit)(Hcit)(OH)] 3, respectively, which both crystallize as two- dimensional frameworks. The layers are either planar and separated by the counter ions in 2 or corrugated and hydrogen bonded to one another in 3. In both 2 and 3, [UO 2 (cit)] 2 4- dimeric subunits with edge-sharing pentagonal bipyramidal uranium coordination polyhedra are present but, in both cases and in contrast with previous structures containing [UO 2 (Hcit)] 2 2- dimers, the carboxylate group not involved in the dimer formation is coordinated to another uranyl unit, which is part of either a centrosymmetric hexagonal bipyramidal bis-aquated group or a different, [(UO 2 ) 2 (Hcit)(OH)] dimer. These examples of two- dimensional assemblages further illustrate the variety of architectures which can be obtained with citric and related acids and the important structure-directing effects of the counter ions. (author)

What Every Textbook Evaluator Should Know.

Science.gov (United States)

Muther, Connie

1985-01-01

Presents information on textbook design and marketing practices, and their consequences for textbook content; recommends that selection committees firmly define the role of the textbook in curriculum, and adapt published materials to their school system's unique requirements. (MCG)

Re-inventing the fiber-optic textbook: a proposal

Science.gov (United States)

Hecht, Jeff; Hecht, Deborah; Chowdary, Ahsan; Massa, Nicholas

2016-09-01

It's time to reinvent the textbook to meet the needs of today's students, educators, and self-study readers. Students aren't buying them, and authors and publishers have slowed or stopped revising them keep up with new technology and new pedagogy. We want to demonstrate new possibilities by completely overhauling Understanding Fiber Optics, an introduction to fiber optics originally written by J.H. for self-study and later republished as a textbook for technician training. After five editions that sold over 100,000 copies, its page count nearly doubled and its price soared more than tenfold from its original $16.95. We envision a modular structure to meet the needs of students and instructors. Basic concepts will be covered at an introductory level in a "core book" of some 200-250 pages, suitable for self-study, STEM programs at the high school level, and technician training. Additional separate modules primarily intended for instructors will cover details, such as how to install connectors. All materials will be distributed electronically at low cost, and will include interactive demonstrations, animations, simulations, and audio and video supplements explaining key concepts. Our goal is to keep the best aspects of a well-written and well-illustrated textbook, take advantage of new tools for presenting material to students, and make the whole package readily accessible and affordable to students, instructors, and anyone else wanting a working knowledge of fiber optics. We are developing a proposal to achieve these goals, and looking for partners to help us develop, test and evaluate instructional materials.

Two-dimensional ferroelectrics

Energy Technology Data Exchange (ETDEWEB)

Blinov, L M; Fridkin, Vladimir M; Palto, Sergei P [A.V. Shubnikov Institute of Crystallography, Russian Academy of Sciences, Moscow, Russian Federaion (Russian Federation); Bune, A V; Dowben, P A; Ducharme, Stephen [Department of Physics and Astronomy, Behlen Laboratory of Physics, Center for Materials Research and Analysis, University of Nebraska-Linkoln, Linkoln, NE (United States)

2000-03-31

The investigation of the finite-size effect in ferroelectric crystals and films has been limited by the experimental conditions. The smallest demonstrated ferroelectric crystals had a diameter of {approx}200 A and the thinnest ferroelectric films were {approx}200 A thick, macroscopic sizes on an atomic scale. Langmuir-Blodgett deposition of films one monolayer at a time has produced high quality ferroelectric films as thin as 10 A, made from polyvinylidene fluoride and its copolymers. These ultrathin films permitted the ultimate investigation of finite-size effects on the atomic thickness scale. Langmuir-Blodgett films also revealed the fundamental two-dimensional character of ferroelectricity in these materials by demonstrating that there is no so-called critical thickness; films as thin as two monolayers (1 nm) are ferroelectric, with a transition temperature near that of the bulk material. The films exhibit all the main properties of ferroelectricity with a first-order ferroelectric-paraelectric phase transition: polarization hysteresis (switching); the jump in spontaneous polarization at the phase transition temperature; thermal hysteresis in the polarization; the increase in the transition temperature with applied field; double hysteresis above the phase transition temperature; and the existence of the ferroelectric critical point. The films also exhibit a new phase transition associated with the two-dimensional layers. (reviews of topical problems)

The Great Depression: A Textbook Case of Problems with American History Textbooks.

Science.gov (United States)

Miller, Steven L.; Rose, Stephen A.

1983-01-01

The 16 US history textbooks reviewed failed to incorporate economists' research on the causes of the Great Depression and consistently presented information that the economics profession has rejected. Strategies that social studies educators might adopt to improve the quality of economic analysis in textbooks is suggested. (Author/RM)

The discourse markers in basic education: a need for systematization in textbooks

Directory of Open Access Journals (Sweden)

Bougleux Bomjardim da Silva Carmo

2014-12-01

Full Text Available In this article, we will discuss the need for a systematization of discourse markers in Basic Education. This proposal emerges from the following ongoing research: “The systematization of contrastive connectors when devising textbooks”, which departs from the pragmatic theories by Portolés (1998, Alomba Ribeiro (2005, and others. Markers are linguistic units with a prominent role in the functioning of language use. However, it is known that textbooks do not show the pragmatic function of certain traditional grammatical categories. So, we selected one out of the textbook collections approved by PNLD 2014, namely, the Perspective: Portuguese collection by Discini and Teixeira (2012 to verify these premises. As a result of the description and analysis we present a illustrative source activity with the discourse marker “but” and its uses in written texts.

Two dimensional polar display of cardiac blood pool SPECT

International Nuclear Information System (INIS)

Honda, Norinari; Machida, Kikuo; Mamiya, Toshio; Takahashi, Taku; Takishima, Teruo; Hasegawa, Noriko; Hashimoto, Masanori; Ohno, Ken

1989-01-01

A new method of ECG gated cardiac blood pool SPECT to illustrate the left ventricular (LV) wall motion in a single static image, two dimensional polar display (2DPD), was described. Circumferential profiles of the difference between end diastolic and end systolic short axis images of the LV were displayed in a similar way to the bull's eye plot of 201 Tl myocardial SPECT. The diagnoses by 2DPDs agreed with those by cinematic displays of ECG gated blood pool SPECT in 74 out of 84 segments (85.5%) of abnormal motion, and 155 out of 168 segments (80.3%) of normal motion. It is concluded that 2DPD can evaluate regional wall motion by a single static image in a significant number of patients, and is also useful in comparing with the bull's eye image of 201 Tl myorcardial SPECT. (orig.)

The New Paradox of the College Textbook.

Science.gov (United States)

Lichtenberg, James

1992-01-01

As college textbooks have become more attractive, sophisticated, and useful, the textbook industry is suffering from high costs, increased popularity of used books, effects of rapidly advancing information and instructional technology, the atypical business structure of the college textbook market, and changing textbook development processes. (MSE)

Two-Dimensional Materials for Sensing: Graphene and Beyond

Directory of Open Access Journals (Sweden)

Seba Sara Varghese

2015-09-01

Full Text Available Two-dimensional materials have attracted great scientific attention due to their unusual and fascinating properties for use in electronics, spintronics, photovoltaics, medicine, composites, etc. Graphene, transition metal dichalcogenides such as MoS2, phosphorene, etc., which belong to the family of two-dimensional materials, have shown great promise for gas sensing applications due to their high surface-to-volume ratio, low noise and sensitivity of electronic properties to the changes in the surroundings. Two-dimensional nanostructured semiconducting metal oxide based gas sensors have also been recognized as successful gas detection devices. This review aims to provide the latest advancements in the field of gas sensors based on various two-dimensional materials with the main focus on sensor performance metrics such as sensitivity, specificity, detection limit, response time, and reversibility. Both experimental and theoretical studies on the gas sensing properties of graphene and other two-dimensional materials beyond graphene are also discussed. The article concludes with the current challenges and future prospects for two-dimensional materials in gas sensor applications.

Chemical constituents from Aspidosperma illustre (Apocynaceae)

International Nuclear Information System (INIS)

Barbosa, Lara F.; Mathias, Leda; Braz-Filho, Raimundo; Vieira, Ivo J. Curcino

2010-01-01

A new natural product oleanane-type triterpene, olean-12-ene-11α-methoxy-3β-acetate (10) was isolated from Aspidosperma illustre, together with β-amyrin (3), lupeol (4), β-amyrin acetate (5), lupeol acetate (6), olean-12-ene-28-hydroxy-3α-tetradecanoate (7), olean-12-ene-28-carboxy-3α-hexadecanoate (8), ursolic acid (9) triterpenes, and two monoterpenic indole alkaloids, b-yoimbine (1) and 1,2-dehydroaspidospermidine (2). These compounds were characterized on their spectral data basis, mainly one- ( 1 H, 13 C, APT) and two-dimensional ( 1 H- 1 H-COSY, 1 H- 1 HNOESY, HMQC and HMBC) NMR, and mass spectra, involving also comparison with data from the literature. (author)

English language teaching textbooks content, consumption, production

CERN Document Server

Harwood, N

2013-01-01

English language teaching textbooks (or coursebooks) play a central role in the life of a classroom. This edited volume contains research-informed chapters focusing on: analysis of textbook content; how textbooks are used in the classroom; and textbook writers' accounts of the materials writing, design, and publishing process.

Two-dimensional calculus

CERN Document Server

Osserman, Robert

2011-01-01

The basic component of several-variable calculus, two-dimensional calculus is vital to mastery of the broader field. This extensive treatment of the subject offers the advantage of a thorough integration of linear algebra and materials, which aids readers in the development of geometric intuition. An introductory chapter presents background information on vectors in the plane, plane curves, and functions of two variables. Subsequent chapters address differentiation, transformations, and integration. Each chapter concludes with problem sets, and answers to selected exercises appear at the end o

The normal vulva in medical textbooks.

Science.gov (United States)

Andrikopoulou, M; Michala, L; Creighton, S M; Liao, L-M

2013-10-01

When a healthy woman expresses concerns about her vulva, the doctor's response should be informed by clinical knowledge. For many doctors, accumulation of such knowledge would have begun with undergraduate teaching and medical textbooks. The aim of this study is to examine the information on female genital morphology in medical textbooks. A total of 59 gynaecology and anatomy textbooks were searched for information on the dimensions of vulval constitutent parts. No textbook gave measurements for all vulval structures. Vaginal length was reported in 21/59 textbooks, clitoral size in 15/59 and labia minora in 1/59. Where measurements appear, they suggest narrower ranges than recent reports. Information of vulval morphology is scanty and inaccurate in medical textbooks. The general lack of professional resources means that doctors may consciously or non-consciously rely upon personal experiences and popular culture to form their opinions, as do their patients.

Phase transitions in two-dimensional systems

International Nuclear Information System (INIS)

Salinas, S.R.A.

1983-01-01

Some experiences are related using synchrotron radiation beams, to characterize solid-liquid (fusion) and commensurate solid-uncommensurate solid transitions in two-dimensional systems. Some ideas involved in the modern theories of two-dimensional fusion are shortly exposed. The systems treated consist of noble gases (Kr,Ar,Xe) adsorbed in the basal plane of graphite and thin films formed by some liquid crystal shells. (L.C.) [pt

Textbook Analysis: Comparing the Recent and the Old First Grade High School English Textbooks, Teachers and Learners’ Perspective in Focus

Directory of Open Access Journals (Sweden)

Nazila Mirzaei

2015-12-01

Full Text Available Abstract The present study was an attempt to investigate and compare the efficiency of the new and the old first grade high school English textbooks by focusing on thirty teachers and three hundred learners’ attitudes through a textbook evaluation checklist and a questionnaire. The analysis of the results revealed that, with regard to teachers' attitude toward the two books compared with each other, these books were nearly the same with regard to pronunciation and exercises. The old book was considered more efficient regarding grammar. Regarding the rest of the items, the new book was more efficient. Taking the learners perspective into account toward these two books compared with each other, there were no noteworthy difference between the books regarding vocabulary. Regarding the other items, the new book was considered more efficient. The findings of this study can assist decision-makers to pay more attention to the evaluation of textbooks and consequently the selection of an appropriate book according to the teachers and learners’ expectations, needs and interests.

Incoming dental students' expectations and acceptance of an electronic textbook program.

Science.gov (United States)

Brunet, Darlene P; Bates, Michael L; Gallo, John R; Strother, Elizabeth A

2011-05-01

Since 2005, the Louisiana State University Health Sciences Center School of Dentistry has required the VitalSource Technologies, Inc. Bookshelf as the textbook program for all dental students. In a 2008 survey, four classes of dental students expressed dissatisfaction with most features of the bookshelf. With the expectation that incoming students would be more accustomed and amenable to digital textbooks and to further determine student attitudes toward electronic textbooks, we developed two surveys for first-year dental students in the class of 2013. The sixty-five first-year students received a survey (S1) one week before they were introduced to the e-textbook program. Questions centered on their undergraduate experience with e-books and their expectations of studying with an electronic textbook collection. In the second survey (S2), sent nine months later, the questions focused on students' opinion of the VitalSource Bookshelf. Forty-five students (69.2 percent) completed the S1 survey. Of those, thirty-six (80 percent) responded that they never used e-textbooks in college. Of the nine students who responded that they used e-books, only two liked them without reservations. The response rate to S2 increased to fifty students (77 percent). After using VitalSource for nine months, thirty-three students (66 percent) indicated a preference for reading print textbooks, compared to forty-seven students (57.3 percent) of the four classes surveyed in 2008. Although we expected incoming dental students to have had previous experience with e-textbooks, only nine students had used e-books in college courses. Few students indicated preference for e-textbooks, and over half of the group was undecided. After experience with VitalSource for first-year courses, students indicated that they like VitalSource for the ability to search for specific topics across the entire collection of dental books, but not for reading large amounts of text.

The Representation of the Cold War in Three Estonian History Textbooks

Science.gov (United States)

Korbits, Keit

2015-01-01

The article looks at the discursive strategies different Estonian history textbooks employ to represent the Cold War period, and the "commonsense" ideologies instilled through these representations. The textbooks analysed include two history books dating back to the Estonian Soviet Socialist Republic and, for contrast, one written during…

The theory of critical phenomena in two-dimensional systems

International Nuclear Information System (INIS)

Olvera de la C, M.

1981-01-01

An exposition of the theory of critical phenomena in two-dimensional physical systems is presented. The first six chapters deal with the mean field theory of critical phenomena, scale invariance of the thermodynamic functions, Kadanoff's spin block construction, Wilson's renormalization group treatment of critical phenomena in configuration space, and the two-dimensional Ising model on a triangular lattice. The second part of this work is made of four chapters devoted to the application of the ideas expounded in the first part to the discussion of critical phenomena in superfluid films, two-dimensional crystals and the two-dimensional XY model of magnetic systems. Chapters seven to ten are devoted to the following subjects: analysis of long range order in one, two, and three-dimensional physical systems. Topological defects in the XY model, in superfluid films and in two-dimensional crystals. The Thouless-Kosterlitz iterated mean field theory of the dipole gas. The renormalization group treatment of the XY model, superfluid films and two-dimensional crystal. (author)

Psychology Ethics in Introductory Psychology Textbooks

Science.gov (United States)

Zucchero, Renee' A.

2011-01-01

Previous research revealed that introductory psychology textbooks included limited information about psychology ethics. This study reviewed 48 current introductory psychology textbooks for research and other APA ethics content. These textbooks included slightly more total ethics content and were more thorough in their review of research ethics…

Qualitative methods textbooks

OpenAIRE

Barndt, William

2003-01-01

Over the past few years, the number of political science departments offering qualitative methods courses has grown substantially. The number of qualitative methods textbooks has kept pace, providing instructors with an overwhelming array of choices. But how to decide which text to choose from this exhortatory smorgasbord? The scholarship desperately needs evaluated. Yet the task is not entirely straightforward: qualitative methods textbooks reflect the diversity inherent in qualitative metho...

Bistatic scattering from a three-dimensional object above a two-dimensional randomly rough surface modeled with the parallel FDTD approach.

Science.gov (United States)

Guo, L-X; Li, J; Zeng, H

2009-11-01

We present an investigation of the electromagnetic scattering from a three-dimensional (3-D) object above a two-dimensional (2-D) randomly rough surface. A Message Passing Interface-based parallel finite-difference time-domain (FDTD) approach is used, and the uniaxial perfectly matched layer (UPML) medium is adopted for truncation of the FDTD lattices, in which the finite-difference equations can be used for the total computation domain by properly choosing the uniaxial parameters. This makes the parallel FDTD algorithm easier to implement. The parallel performance with different number of processors is illustrated for one rough surface realization and shows that the computation time of our parallel FDTD algorithm is dramatically reduced relative to a single-processor implementation. Finally, the composite scattering coefficients versus scattered and azimuthal angle are presented and analyzed for different conditions, including the surface roughness, the dielectric constants, the polarization, and the size of the 3-D object.

"Textbook as a Contradictory Melting-Pot": An Analysis of Multicultural Content in Korean Textbooks

Science.gov (United States)

Cho, Youngdal; Park, Yunkyoung

2016-01-01

In this study we will observe how multicultural content is covered in elementary and secondary schools in Korea. For this purpose, a total of 52 textbooks (social studies, ethics and Korean language from third to ninth grade) were analysed using two analysis frames. The first frame is the "multicultural content analysis frame (MCAF)"…

Social history of health psychology: context and textbooks.

Science.gov (United States)

Murray, Michael

2014-01-01

Health psychology as a field of research and practice formally developed 30 years ago but it was prefigured by sustained debate within social and applied psychology about the nature of psychology and its role in society. This article considers this pre-history of health psychology and how the field has subsequently developed. It considers how its character is shaped by dominant ideas within psychology and is also enmeshed in broader social relations. To illustrate the changing character of health psychology it considers how the field is represented in a selection of popular textbooks. It concludes by considering the growth of some critical approaches within health psychology.

Textbook of radiology

International Nuclear Information System (INIS)

Putman, C.E.; Ravin, C.E.

1987-01-01

This book is presented in two volumes, standard textbook of imaging, conclusive and totally up-to-date. This provides information organized by major topics covering the state-of-the-art for all imaging procedures. The volume 1 presents radiologic physics and technology by discussing roentgenography, ultrasound, CT, nuclear medicine, MRI, and positron emission tomography. The volume 2 studies pulmonary radiology, imaging of the skeletal and central nervous systems, uroradiology, abdominal and cardiac imaging, and imaging of the pelvis

Naïve Conceptions About Multimedia Learning:A Study on Primary School Textbooks

OpenAIRE

Barbara eColombo; Alessandro eAntonietti

2013-01-01

An interview study, based on specific pictures taken from textbooks used in primary schools, was carried out to investigate illustrators’, teachers’, students’, and common people’s beliefs about the role that illustrations play in facilitating learning. Participants’ responses were internally coherent, indicating a systematic nature of the underlying naïve conceptions. Findings disprove Mayer’s pessimistic claim that laypersons’ conceptions of multimedia learning fail to match experiment...

Practical textbook of cardiac CT and MRI

Energy Technology Data Exchange (ETDEWEB)

Lim, Tae-Hwan (ed.) [ASAN Medical Center, Seoul (Korea, Republic of). Dept. of Radiology

2015-04-01

Guide to the interpretation of cardiac CT and MRI for the purposes of diagnosis, treatment planning, and follow-up. Emphasis on applications in a wide range of real clinical situations. Numerous informative illustrations. Summarizing sections permitting rapid retrieval of information. QR codes allowing access to references, additional figures, and motion pictures from the internet. This up-to-date textbook comprehensively reviews all aspects of cardiac CT and MRI and demonstrates the value of these techniques in clinical practice. A wide range of applications are considered, including imaging of atherosclerotic and non-atherosclerotic coronary artery disease, coronary revascularization, ischemic heart disease, non-ischemic cardiomyopathy, valvular heart disease, cardiac tumors, and pericardial disease. The numerous high-quality images illustrate how to interpret cardiac CT and MRI correctly for the purposes of diagnosis, treatment planning, and follow-up. Helpful summarizing sections in every chapter will facilitate rapid retrieval of information. This book will be of great value to radiologists and cardiologists seeking a reliable guide to the optimal use of cardiac CT and MRI in real clinical situations.

Practical textbook of cardiac CT and MRI

International Nuclear Information System (INIS)

Lim, Tae-Hwan

2015-01-01

Guide to the interpretation of cardiac CT and MRI for the purposes of diagnosis, treatment planning, and follow-up. Emphasis on applications in a wide range of real clinical situations. Numerous informative illustrations. Summarizing sections permitting rapid retrieval of information. QR codes allowing access to references, additional figures, and motion pictures from the internet. This up-to-date textbook comprehensively reviews all aspects of cardiac CT and MRI and demonstrates the value of these techniques in clinical practice. A wide range of applications are considered, including imaging of atherosclerotic and non-atherosclerotic coronary artery disease, coronary revascularization, ischemic heart disease, non-ischemic cardiomyopathy, valvular heart disease, cardiac tumors, and pericardial disease. The numerous high-quality images illustrate how to interpret cardiac CT and MRI correctly for the purposes of diagnosis, treatment planning, and follow-up. Helpful summarizing sections in every chapter will facilitate rapid retrieval of information. This book will be of great value to radiologists and cardiologists seeking a reliable guide to the optimal use of cardiac CT and MRI in real clinical situations.

Should Geography Educators Adopt Electronic Textbooks?

Science.gov (United States)

Romig, Kevin

2017-01-01

Significant changes in textbook publishing are at college instructors' door. Textbook representatives are directed to mesmerize potential clients with eye-catching displays and statements about digital literacy of the next generation of college students. Based on a one-year pilot study, in 2014-2015, of an electronic textbook, this commentary…

Explaining Teachers' Use of Textbooks

Science.gov (United States)

Reichenberg, Monica

2016-01-01

In educational systems without comprehensive systems for regulating textbooks, teachers can exert considerable influence on the use of textbooks. However, existing research has not yet identified the mechanisms of this use. Accordingly, the aim of this article is to examine and explain teachers' strategic use of textbooks. I administered a…

An innovative textbook: design and implementation.

Science.gov (United States)

Ortega, Rafael; Akhtar-Khavari, Vafa; Barash, Paul; Sharar, Sam; Stock, M Christine

2017-12-01

The 'flipped classroom' instructional strategy has gained much momentum in educational discourse, yet no single educational offering exists in postgraduate medical education (PME) to systematically replace the lecture element of didactic sessions. This article describes the design and implementation of Clinical Anesthesia Fundamentals, the first known textbook in PME addressing this gap in resources through the integration of full-length interactive multimedia-enhanced video lectures. The 'flipped classroom' instructional strategy has gained much momentum in educational discourse INNOVATION: The textbook was developed in alignment with the content outline for the specialty provided by the American Board of Anesthesiology. Its accompanying video lectures, produced at the Media Lab in the Department of Anesthesiology at Boston University Medical Center (BUMC), cover the topics in each chapter of the textbook and include review questions featuring explanatory feedback. Following a 5-month trial period at the BUMC Anesthesiology Residency Program, the complete resident class (25 of 25; 100%) participated in an anonymous, Institutional Review Board (IRB) -approved, five-point Likert-type scale survey assessing an underlying variable of preference for the use of multimedia learning tools. Survey results suggest that residents favour technology-enhanced learning environments in which textbooks are coupled with interactive multimedia, and the 'flipped classroom' approach is employed. Although the development of digital videos requires time and financial investment, the improved accessibility and uniform delivery of didactic content are two positive outcomes. This textbook provides an example for educators wishing to learn how to capitalise on advances in technology to further enhance learning and accessibility. Further studies could address the impact of this approach on the academic performance of residents. © 2016 John Wiley & Sons Ltd and The Association for the Study

Two- and three-dimensional CT analysis of ankle fractures

International Nuclear Information System (INIS)

Magid, D.; Fishman, E.K.; Ney, D.R.; Kuhlman, J.E.

1988-01-01

CT with coronal and sagittal reformatting (two-dimensional CT) and animated volumetric image rendering (three-dimensional CT) was used to assess ankle fractures. Partial volume limits transaxial CT in assessments of horizontally oriented structures. Two-dimensional CT, being orthogonal to the plafond, superior mortise, talar dome, and tibial epiphysis, often provides the most clinically useful images. Two-dimensional CT is most useful in characterizing potentially confusing fractures, such as Tillaux (anterior tubercle), triplane, osteochondral talar dome, or nondisplaced talar neck fractures, and it is the best study to confirm intraarticular fragments. Two-and three-dimensional CT best indicate the percentage of articular surface involvement and best demonstrate postoperative results or complications (hardware migration, residual step-off, delayed union, DJD, AVN, etc). Animated three-dimensional images are the preferred means of integrating the two-dimensional findings for surgical planning, as these images more closely simulate the clinical problem

On two-dimensionalization of three-dimensional turbulence in shell models

DEFF Research Database (Denmark)

Chakraborty, Sagar; Jensen, Mogens Høgh; Sarkar, A.

2010-01-01

Applying a modified version of the Gledzer-Ohkitani-Yamada (GOY) shell model, the signatures of so-called two-dimensionalization effect of three-dimensional incompressible, homogeneous, isotropic fully developed unforced turbulence have been studied and reproduced. Within the framework of shell m......-similar PDFs for longitudinal velocity differences are also presented for the rotating 3D turbulence case....

Two-dimensional turbulent convection

Science.gov (United States)

Mazzino, Andrea

2017-11-01

We present an overview of the most relevant, and sometimes contrasting, theoretical approaches to Rayleigh-Taylor and mean-gradient-forced Rayleigh-Bénard two-dimensional turbulence together with numerical and experimental evidences for their support. The main aim of this overview is to emphasize that, despite the different character of these two systems, especially in relation to their steadiness/unsteadiness, turbulent fluctuations are well described by the same scaling relationships originated from the Bolgiano balance. The latter states that inertial terms and buoyancy terms balance at small scales giving rise to an inverse kinetic energy cascade. The main difference with respect to the inverse energy cascade in hydrodynamic turbulence [R. H. Kraichnan, "Inertial ranges in two-dimensional turbulence," Phys. Fluids 10, 1417 (1967)] is that the rate of cascade of kinetic energy here is not constant along the inertial range of scales. Thanks to the absence of physical boundaries, the two systems here investigated turned out to be a natural physical realization of the Kraichnan scaling regime hitherto associated with the elusive "ultimate state of thermal convection" [R. H. Kraichnan, "Turbulent thermal convection at arbitrary Prandtl number," Phys. Fluids 5, 1374-1389 (1962)].

Education and Textbooks

OpenAIRE

Simon, Josep; García-Belmar, Antonio

2016-01-01

Education and textbooks have traditionally been standard objects of research in the history of science, technology, and medicine. However, they have often remained marginal in the formulation of large historiographical questions. In the last decades, the work of some historians of science has challenged this state of affairs. STEP has promoted a distinctive focus on education and textbooks, compared to other scholarship cultures such as the Anglo-American. This essay reviews its work in this ...

What's Wrong with Economics Textbooks?

Science.gov (United States)

Culyer, A. J.

1985-01-01

Many things are wrong with college level economics textbooks. For example, they are too ahistorical, too particularist, or unsystematically eclectic. The requirements of a good college economics textbook are examined. (RM)

Do E-Textbooks Impact Learning Outcomes?

Science.gov (United States)

Fike, David; Fike, Renea

2016-01-01

The primary focus of this study was to determine if student learning outcomes in an undergraduate Statistics course differed based upon the type of textbook used (e-textbook or hardcopy). Fifty-six students enrolled in the course were allowed to choose textbook type. After controlling for student demographics and academic preparedness, student…

Multi-perspective views of students’ difficulties with one-dimensional vector and two-dimensional vector

Science.gov (United States)

Fauzi, Ahmad; Ratna Kawuri, Kunthi; Pratiwi, Retno

2017-01-01

Researchers of students’ conceptual change usually collects data from written tests and interviews. Moreover, reports of conceptual change often simply refer to changes in concepts, such as on a test, without any identification of the learning processes that have taken place. Research has shown that students have difficulties with vectors in university introductory physics courses and high school physics courses. In this study, we intended to explore students’ understanding of one-dimensional and two-dimensional vector in multi perspective views. In this research, we explore students’ understanding through test perspective and interviews perspective. Our research study adopted the mixed-methodology design. The participants of this research were sixty students of third semester of physics education department. The data of this research were collected by testand interviews. In this study, we divided the students’ understanding of one-dimensional vector and two-dimensional vector in two categories, namely vector skills of the addition of one-dimensionaland two-dimensional vector and the relation between vector skills and conceptual understanding. From the investigation, only 44% of students provided correct answer for vector skills of the addition of one-dimensional and two-dimensional vector and only 27% students provided correct answer for the relation between vector skills and conceptual understanding.

Optimizing separations in online comprehensive two-dimensional liquid chromatography.

Science.gov (United States)

Pirok, Bob W J; Gargano, Andrea F G; Schoenmakers, Peter J

2018-01-01

Online comprehensive two-dimensional liquid chromatography has become an attractive option for the analysis of complex nonvolatile samples found in various fields (e.g. environmental studies, food, life, and polymer sciences). Two-dimensional liquid chromatography complements the highly popular hyphenated systems that combine liquid chromatography with mass spectrometry. Two-dimensional liquid chromatography is also applied to the analysis of samples that are not compatible with mass spectrometry (e.g. high-molecular-weight polymers), providing important information on the distribution of the sample components along chemical dimensions (molecular weight, charge, lipophilicity, stereochemistry, etc.). Also, in comparison with conventional one-dimensional liquid chromatography, two-dimensional liquid chromatography provides a greater separation power (peak capacity). Because of the additional selectivity and higher peak capacity, the combination of two-dimensional liquid chromatography with mass spectrometry allows for simpler mixtures of compounds to be introduced in the ion source at any given time, improving quantitative analysis by reducing matrix effects. In this review, we summarize the rationale and principles of two-dimensional liquid chromatography experiments, describe advantages and disadvantages of combining different selectivities and discuss strategies to improve the quality of two-dimensional liquid chromatography separations. © 2017 The Authors. Journal of Separation Science published by WILEY-VCH Verlag GmbH & Co. KGaA.

A Pedagogic Corpus Analysis: Modal Auxiliary Verbs in Malaysian English Textbooks

Science.gov (United States)

Khojasteh, Laleh; Mukundan, Jayakaran

2011-01-01

Using corpus approach, over the past two decades, a growing number of researchers started to blame textbooks for neglecting important information on the use of grammatical structures in real language use and provided ample information about the mismatch between language used in textbooks and real language in use. Likewise, the prescribed Malaysian…

Numerical and dimensional investigation of two-phase countercurrent imbibition in porous media

KAUST Repository

El-Amin, Mohamed

2013-04-01

In this paper, we introduce a numerical solution of the problem of two-phase immiscible flow in porous media. In the first part of this work, we present the general conservation laws for multiphase flows in porous media as outlined in the literature for the sake of completion where we emphasize the difficulties associated with these equations in their primitive form and the fact that they are, generally, unclosed. The second part concerns the 1D computation for dimensional and non-dimensional cases and a theoretical analysis of the problem under consideration. A time-scale based on the characteristic velocity is used to transform the macroscopic governing equations into a non-dimensional form. The resulting dimensionless governing equations involved some important dimensionless physical parameters such as Bond number Bo, capillary number Ca and Darcy number Da. Numerical experiments on the Bond number effect is performed for two cases, gravity opposing and assisting. The theoretical analysis illustrates that common formulations of the time-scale forces the coefficient Da12Ca to be equal to one, while formulation of dimensionless time based on a characteristic velocity allows the capillary and Darcy numbers to appear in the dimensionless governing equation which leads to a wide range of scales and physical properties of fluids and rocks. The results indicate that the buoyancy effects due to gravity force take place depending on the location of the open boundary. © 2012 Elsevier B.V. All rights reserved.

Depictions of females and males in Mozambican and Victorian (Australia primary mathematics textbooks

Directory of Open Access Journals (Sweden)

Adelino Evaristo Murimo

2007-10-01

Full Text Available The depiction of females and males in Mozambican Primary Mathematics textbooks for grades 6 and 7 were examined, and comparisons made with Victorian  (Australia textbooks for years 5 and 6. It was found that mathematics learning was portrayed as a  male domain in the Mozambican textbooks, reflecting what used to be the case with Australian texts of the 1970s, although there are some differences between the two countries that may be culturally based. The Victorian textbooks depicted mathematics learning as a domain for all children, and in the majority of categories examined, females and males were distributed fairly evenly. Compared to earlier reported findings, there was a general improvement in the portrayal of females in Victorian textbooks.

A Comparative Analysis of Quadratics Unit in Singaporean, Turkish and IBDP Mathematics Textbooks

Directory of Open Access Journals (Sweden)

Reyhan Sağlam

2012-12-01

Full Text Available The purpose of this study was to analyze and compare the contents of the chapters on quadratics in three mathematics textbooks selected from Turkey, Singapore, and the International Baccalaureate Diploma Program (IBDP through content analysis. The analysis of mathematical content showed that the three textbooks have different approaches and priorities in terms of the positions of chapters and weights of the quadratics units, and the time allocated to them within the respective curricular programs. It was also found that the Turkish textbook covers a greater number of learning outcomes targeted for quadratics among the three mathematics syllabi, showing a detailed treatment of the topic compared to the other two textbooks.Key Words: Content analysis, international comparative studies, mathematics textbooks

Two-dimensional liquid chromatography

DEFF Research Database (Denmark)

Græsbøll, Rune

-dimensional separation space. Optimization of gradients in online RP×RP is more difficult than in normal HPLC as a result of the increased number of parameters and their influence on each other. Modeling the coverage of the compounds across the two-dimensional chromatogram as a result of a change in gradients could...... be used for optimization purposes, and reduce the time spend on optimization. In this thesis (chapter 6), and manuscript B, a measure of the coverage of the compounds in the twodimensional separation space is defined. It is then shown that this measure can be modeled for changes in the gradient in both...

The Evolution of International Business Textbooks

Science.gov (United States)

Sagafi-nejad, Tagi; Limaye, Aditya

2014-01-01

As a field of study, international business (IB) has evolved with accelerated tempo in the last four decades. The subject has brought with it an increasing plethora of textbooks. We analyze the contents of major textbooks, both classic and new, to find the extent to which these textbooks cover the various components of the common body of knowledge…

Two-dimensional simulation of sintering process

International Nuclear Information System (INIS)

Vasconcelos, Vanderley de; Pinto, Lucio Carlos Martins; Vasconcelos, Wander L.

1996-01-01

The results of two-dimensional simulations are directly applied to systems in which one of the dimensions is much smaller than the others, and to sections of three dimensional models. Moreover, these simulations are the first step of the analysis of more complex three-dimensional systems. In this work, two basic features of the sintering process are studied: the types of particle size distributions related to the powder production processes and the evolution of geometric parameters of the resultant microstructures during the solid-state sintering. Random packing of equal spheres is considered in the sintering simulation. The packing algorithm does not take into account the interactive forces between the particles. The used sintering algorithm causes the densification of the particle set. (author)

Automatic Generation of Stippling Illustrations from two Photographs

Directory of Open Access Journals (Sweden)

Germán Arroyo

2012-05-01

This tool needs almost no user interaction. The user simply has to align both photographs and indicate the level of detail according to the distance. The rest is decided by our software. Whereas a professional illustrator needs more than 20 hours to finish a similar illustration, our software is able to do it in just few seconds.

Java vs. Python Coverage of Introductory Programming Concepts: A Textbook Analysis

Science.gov (United States)

McMaster, Kirby; Sambasivam, Samuel; Rague, Brian; Wolthuis, Stuart

2017-01-01

In this research, we compare two languages, Java and Python, by performing a content analysis of words in textbooks that describe important programming concepts. Our goal is to determine which language has better textbook support for teaching introductory programming courses. We used the TextSTAT program to count how often our list of concept…

Volume illustration of muscle from diffusion tensor images.

Science.gov (United States)

Chen, Wei; Yan, Zhicheng; Zhang, Song; Crow, John Allen; Ebert, David S; McLaughlin, Ronald M; Mullins, Katie B; Cooper, Robert; Ding, Zi'ang; Liao, Jun

2009-01-01

Medical illustration has demonstrated its effectiveness to depict salient anatomical features while hiding the irrelevant details. Current solutions are ineffective for visualizing fibrous structures such as muscle, because typical datasets (CT or MRI) do not contain directional details. In this paper, we introduce a new muscle illustration approach that leverages diffusion tensor imaging (DTI) data and example-based texture synthesis techniques. Beginning with a volumetric diffusion tensor image, we reformulate it into a scalar field and an auxiliary guidance vector field to represent the structure and orientation of a muscle bundle. A muscle mask derived from the input diffusion tensor image is used to classify the muscle structure. The guidance vector field is further refined to remove noise and clarify structure. To simulate the internal appearance of the muscle, we propose a new two-dimensional example based solid texture synthesis algorithm that builds a solid texture constrained by the guidance vector field. Illustrating the constructed scalar field and solid texture efficiently highlights the global appearance of the muscle as well as the local shape and structure of the muscle fibers in an illustrative fashion. We have applied the proposed approach to five example datasets (four pig hearts and a pig leg), demonstrating plausible illustration and expressiveness.

State operator, constants of the motion, and Wigner functions: The two-dimensional isotropic harmonic oscillator

DEFF Research Database (Denmark)

Dahl, Jens Peder; Schleich, W. P.

2009-01-01

For a closed quantum system the state operator must be a function of the Hamiltonian. When the state is degenerate, additional constants of the motion enter the play. But although it is the Weyl transform of the state operator, the Wigner function is not necessarily a function of the Weyl...... transforms of the constants of the motion. We derive conditions for which this is actually the case. The Wigner functions of the energy eigenstates of a two-dimensional isotropic harmonic oscillator serve as an important illustration....

Chaotic dynamics in two-dimensional noninvertible maps

CERN Document Server

Mira, Christian; Cathala, Jean-Claude; Gardini, Laura

1996-01-01

This book is essentially devoted to complex properties (Phase plane structure and bifurcations) of two-dimensional noninvertible maps, i.e. maps having either a non-unique inverse, or no real inverse, according to the plane point. They constitute models of sets of discrete dynamical systems encountered in Engineering (Control, Signal Processing, Electronics), Physics, Economics, Life Sciences. Compared to the studies made in the one-dimensional case, the two-dimensional situation remained a long time in an underdeveloped state. It is only since these last years that the interest for this resea

Application of a method for comparing one-dimensional and two-dimensional models of a ground-water flow system

International Nuclear Information System (INIS)

Naymik, T.G.

1978-01-01

To evaluate the inability of a one-dimensional ground-water model to interact continuously with surrounding hydraulic head gradients, simulations using one-dimensional and two-dimensional ground-water flow models were compared. This approach used two types of models: flow-conserving one-and-two dimensional models, and one-dimensional and two-dimensional models designed to yield two-dimensional solutions. The hydraulic conductivities of controlling features were varied and model comparison was based on the travel times of marker particles. The solutions within each of the two model types compare reasonably well, but a three-dimensional solution is required to quantify the comparison

[The early medical textbooks in Korea: medical textbooks published at Je Joong Won-Severance Hospital Medical School].

Science.gov (United States)

Park, H W

1998-01-01

Kwang Hye Won(Je Joong Won), the first western hospital in Korea, was founded in 1885. The first western Medical School in Korea was open in 1886 under the hospital management. Dr. O. R. Avison, who came to Korea in 1893, resumed the medical education there, which was interrupted for some time before his arrival in Korea. He inaugurated translating and publishing medical textbooks with the help of Kim Pil Soon who later became one of the first seven graduates in Severance Hospital Medical School. The first western medical textbook translated into Korean was Henry Gray's Anatomy. However, these twice-translated manuscripts were never to be published on account of being lost and burnt down. The existing early anatomy textbooks, the editions of 1906 and 1909, are not the translation of Gray's Anatomy, but that of Japanese anatomy textbook of Gonda. The remaining oldest medical textbook in Korean is Inorganic Materia Medica published in 1905. This book is unique among its kind that O. R. Avison is the only translator of the book and it contains the prefaces of O. R. Avison and Kim Pil Soon. The publication of medical textbook was animated by the participation of other medical students, such as Hong Suk Hoo and Hong Jong Eun. The list of medical textbooks published includes almost all the field of medicine. The medical textbooks in actual existence are as follows: Inorganic Materia Medica (1905), Inorganic Chemistry (1906), Anatomy I (1906), Physiology (1906), Diagnostics I (1906), Diagnostics II (1907), Obstetrics (1908), Organic Chemistry (1909), Anatomy (1909), and Surgery (1910).

As Good or Better than Commercial Textbooks: Students’ Perceptions and Outcomes from Using Open Digital and Open Print Textbooks

Directory of Open Access Journals (Sweden)

Rajiv S. Jhangiani

2018-04-01

Full Text Available The increase in the cost of college textbooks together with the proliferation of digital content and devices has inspired the development of open textbooks, open educational resources that are free, openly licensed, and often peer-reviewed. Although several published studies have investigated the impact of open textbook adoption on educational outcomes, none have separated the effects of textbook openness and format and only two have taken place in Canada (Hendricks, Reinsberg, & Rieger, 2017; Jhangiani & Jhangiani, 2017. This study investigates the perceptions, use, and course performance of Canadian post-secondary students assigned a commercial or open textbook in either print or digital format. Results show that students using the print format of the open textbook perceive its quality to be superior to the commercial textbook. Moreover, students assigned an open textbook in either format perform either no differently from or better than those assigned a commercial textbook. These results are consistent with the existing literature and support the conclusion that the cost savings to students associated with the adoption of open textbooks do not come at the expense of resource quality or student performance. L’augmentation du coût des manuels universitaires ainsi que la prolifération du contenu numérique et des appareils électroniques ont inspiré le développement de manuels ouverts, des ressources éducationnelles qui sont gratuites, dont les licences d’exploitation sont ouvertes et qui sont souvent évalués par les pairs. Bien que plusieurs études publiées aient étudié l’impact de l’adoption de manuels ouverts sur les résultats éducationnels, aucune n’a séparé les effets du caractère ouvert des manuels et du format et seulement deux études ont été menées au Canada (Hendricks, Reinsberg & Rieger, 2017; Jhangiani & Jhangiani, 2017. Cette étude examine les perceptions, l’emploi et les résultats des �

Two-dimensional analytic weighting functions for limb scattering

Science.gov (United States)

Zawada, D. J.; Bourassa, A. E.; Degenstein, D. A.

2017-10-01

Through the inversion of limb scatter measurements it is possible to obtain vertical profiles of trace species in the atmosphere. Many of these inversion methods require what is often referred to as weighting functions, or derivatives of the radiance with respect to concentrations of trace species in the atmosphere. Several radiative transfer models have implemented analytic methods to calculate weighting functions, alleviating the computational burden of traditional numerical perturbation methods. Here we describe the implementation of analytic two-dimensional weighting functions, where derivatives are calculated relative to atmospheric constituents in a two-dimensional grid of altitude and angle along the line of sight direction, in the SASKTRAN-HR radiative transfer model. Two-dimensional weighting functions are required for two-dimensional inversions of limb scatter measurements. Examples are presented where the analytic two-dimensional weighting functions are calculated with an underlying one-dimensional atmosphere. It is shown that the analytic weighting functions are more accurate than ones calculated with a single scatter approximation, and are orders of magnitude faster than a typical perturbation method. Evidence is presented that weighting functions for stratospheric aerosols calculated under a single scatter approximation may not be suitable for use in retrieval algorithms under solar backscatter conditions.

Gender Representation in Elementary Level, African Language Textbooks

Directory of Open Access Journals (Sweden)

Antonia Folarin Schleicher

2004-01-01

Full Text Available Foreign language learners' perceptions and understanding of a target culture(s are affected by the infonnation presented by their teacher(s, textbooks and other instructional materials. This paper focuses on an analysis of gender representation in elementary level, African language textbooks, with a specific concentration on Hausa, Swahili, Yoruba, and Zulu textbooks. Although the study of gender representation in textbooks is not new (see Blankenship, 1984; Clausen, 1982; Neussel, 1977 and others, relatively few authors have focused on gender representation in foreign language textbooks (Graci, 1989; Rifkin, 1998. This study seeks to extend the work of these scholars into the field of African languages. As a result, the present analysis focuses on (1 establishing criteria for evaluating African language textbooks for gender representation; (2 applying these criteria to seventeen different, elementary level, African language textbooks to create a basis for a comparative case study; (3 presenting the findings of a detailed analysis; and ( 4 utilizing the findings to formulate guidelines for future textbook writers.

Game theory: Parts I and II - with 88 solved exercises. An open access textbook

OpenAIRE

Bonanno, Giacomo

2015-01-01

This is a draft of the first half of an open access textbook on game theory. I hope to complete the entire book by the end of 2015. After teaching game theory (at both the undergraduate and graduate level) at the University of California, Davis for 25 years, I decided to organize all my teaching material in a textbook. There are many excellent textbooks in game theory and there is hardly any need for a new one. However, there are two distinguishing features of this textbook: (1) it is open ac...

Depth-enhanced three-dimensional-two-dimensional convertible display based on modified integral imaging.

Science.gov (United States)

Park, Jae-Hyeung; Kim, Hak-Rin; Kim, Yunhee; Kim, Joohwan; Hong, Jisoo; Lee, Sin-Doo; Lee, Byoungho

2004-12-01

A depth-enhanced three-dimensional-two-dimensional convertible display that uses a polymer-dispersed liquid crystal based on the principle of integral imaging is proposed. In the proposed method, a lens array is located behind a transmission-type display panel to form an array of point-light sources, and a polymer-dispersed liquid crystal is electrically controlled to pass or to scatter light coming from these point-light sources. Therefore, three-dimensional-two-dimensional conversion is accomplished electrically without any mechanical movement. Moreover, the nonimaging structure of the proposed method increases the expressible depth range considerably. We explain the method of operation and present experimental results.

A Fibonacci collocation method for solving a class of Fredholm–Volterra integral equations in two-dimensional spaces

Directory of Open Access Journals (Sweden)

Farshid Mirzaee

2014-06-01

Full Text Available In this paper, we present a numerical method for solving two-dimensional Fredholm–Volterra integral equations (F-VIE. The method reduces the solution of these integral equations to the solution of a linear system of algebraic equations. The existence and uniqueness of the solution and error analysis of proposed method are discussed. The method is computationally very simple and attractive. Finally, numerical examples illustrate the efficiency and accuracy of the method.

Exploring Culture in Locally Published English Textbooks for Primary Education in Turkey

Science.gov (United States)

Kirkgöz, Yasemin; Agçam, Reyhan

2011-01-01

Since language and culture are closely interwoven, the integration of culture into textbooks used for teaching English as a second/foreign language has become a widely accepted phenomenon. This study investigates the cultural elements in locally published English textbooks used for Turkish primary schools following two major curriculum innovations…

The history and illustration of anatomy in the Middle Ages.

Science.gov (United States)

Gurunluoglu, Raffi; Gurunluoglu, Aslin; Williams, Susan A; Cavdar, Safiye

2013-11-01

This article reviews the influence of key figures on the pictorial representation of anatomy and the evolution of anatomical illustration during the Middle Ages until the time of the Renaissance, based on medical history books, journals and ancient medical books. During the early period in the Middle Ages, most illustrations were traditional drawings of emblematic nature, oftentimes unrealistic, not only because the precise knowledge of anatomy was lacking but also because the objective was to elucidate certain principles for teaching purposes. Five figure-series that came down to us through ancient manuscripts and textbooks represent the best examples of such traditional illustrations. With the advent of human dissection in the 13th and 14th centuries, a significant transformation in the depiction of anatomy began to project the practice of human dissection, as we see in the works of Mondino de Luzzi, Henri de Mondeville and Guido de Vigevano. After the invention of book printing in the second half of the 15th century, the reproduction of books was commonly practised and the woodcut made multiplication of pictures easier. Peter of Abano, Hieronymous Brunschwig, Johannes de Ketham, Johannes Peyligk, Gregory Reisch, Magnus Hundt, Laurentius Phryesen and many more included several anatomical illustrations in their treatises that demonstrated the development of anatomical illustration during the later Middle Ages.

Functional inks and printing of two-dimensional materials.

Science.gov (United States)

Hu, Guohua; Kang, Joohoon; Ng, Leonard W T; Zhu, Xiaoxi; Howe, Richard C T; Jones, Christopher G; Hersam, Mark C; Hasan, Tawfique

2018-05-08

Graphene and related two-dimensional materials provide an ideal platform for next generation disruptive technologies and applications. Exploiting these solution-processed two-dimensional materials in printing can accelerate this development by allowing additive patterning on both rigid and conformable substrates for flexible device design and large-scale, high-speed, cost-effective manufacturing. In this review, we summarise the current progress on ink formulation of two-dimensional materials and the printable applications enabled by them. We also present our perspectives on their research and technological future prospects.

Methods of Use of an Online Economics Textbook

Science.gov (United States)

Miller, Jon R.; Baker-Eveleth, Lori

2010-01-01

The rising cost of college textbooks over the last decade provides an opportunity for alternatives. Electronic or online textbooks are an effective substitute to the traditional paper-based textbooks, although students have been slow to transition to the new method. A custom, professor-written online textbook not only addresses the reduction in…

K-FIX: a computer program for transient, two-dimensional, two-fluid flow. THREED: an extension of the K-FIX code for three-dimensional calculations

International Nuclear Information System (INIS)

Rivard, W.C.; Torrey, M.D.

1978-10-01

The transient, two-dimensional, two-fluid code K-FIX has been extended to perform three-dimensional calculations. This capability is achieved by adding five modification sets of FORTRAN statements to the basic two-dimensional code. The modifications are listed and described, and a complete listing of the three-dimensional code is provided. Results of an example problem are provided for verification

The direct field boundary impedance of two-dimensional periodic structures with application to high frequency vibration prediction.

Science.gov (United States)

Langley, Robin S; Cotoni, Vincent

2010-04-01

Large sections of many types of engineering construction can be considered to constitute a two-dimensional periodic structure, with examples ranging from an orthogonally stiffened shell to a honeycomb sandwich panel. In this paper, a method is presented for computing the boundary (or edge) impedance of a semi-infinite two-dimensional periodic structure, a quantity which is referred to as the direct field boundary impedance matrix. This terminology arises from the fact that none of the waves generated at the boundary (the direct field) are reflected back to the boundary in a semi-infinite system. The direct field impedance matrix can be used to calculate elastic wave transmission coefficients, and also to calculate the coupling loss factors (CLFs), which are required by the statistical energy analysis (SEA) approach to predicting high frequency vibration levels in built-up systems. The calculation of the relevant CLFs enables a two-dimensional periodic region of a structure to be modeled very efficiently as a single subsystem within SEA, and also within related methods, such as a recently developed hybrid approach, which couples the finite element method with SEA. The analysis is illustrated by various numerical examples involving stiffened plate structures.

Posology of insulins: A review of standard textbooks and product inserts.

Science.gov (United States)

Bhutani, Garima; Kalra, Sanjay

2015-01-01

The study is aimed to assess whether the information contained in standard pharmacology, endocrinology, and diabetology textbooks regarding timings of administration, frequency and dose of various insulins is adequate and also to see whether the information contained in these texts is concordant with product inserts. Four standard textbooks of pharmacology, two of diabetology and three of endocrinology were assessed for the published information regarding dose, timing, and frequency of insulin administration. The product inserts of commonly available insulins in India were also studied for the same. Various omissions and disparities could be seen in the coverage of insulins in standard textbooks. Posology information about premixed insulins and basal insulins have been omitted by the majority of the textbooks. Details about dose, frequency and timings of ultra-short acting insulins have also not been covered by all textbooks. Some discrepancies regarding prescribing information was also noted in product inserts, especially in case of newer insulins. Thus, this article stresses upon the need of a uniform source of information for providing adequate and standardized knowledge regarding timing, frequency, and dose of insulins.

On integrability of a noncommutative q-difference two-dimensional Toda lattice equation

Energy Technology Data Exchange (ETDEWEB)

Li, C.X., E-mail: trisha_li2001@163.com [School of Mathematical Sciences, Capital Normal University, Beijing 100048 (China); Department of Mathematics, College of Charleston, Charleston, SC 29401 (United States); Nimmo, J.J.C., E-mail: jonathan.nimmo@glasgow.ac.uk [School of Mathematics and Statistics, University of Glasgow, Glasgow G12 8QW (United Kingdom); Shen, Shoufeng, E-mail: mathssf@zjut.edu.cn [Department of Applied Mathematics, Zhejiang University of Technology, Hangzhou 310023 (China)

2015-12-18

In our previous work (C.X. Li and J.J.C. Nimmo, 2009 [18]), we presented a generalized type of Darboux transformations in terms of a twisted derivation in a unified form. The twisted derivation includes ordinary derivatives, forward difference operators, super derivatives and q-difference operators as its special cases. This result not only enables one to recover the known Darboux transformations and quasideterminant solutions to the noncommutative KP equation, the non-Abelian two-dimensional Toda lattice equation, the non-Abelian Hirota–Miwa equation and the super KdV equation, but also inspires us to investigate quasideterminant solutions to q-difference soliton equations. In this paper, we first construct the bilinear Bäcklund transformations for the known bilinear q-difference two-dimensional Toda lattice equation (q-2DTL) and then derive a Lax pair whose compatibility gives a formally different nonlinear q-2DTL equation and finally obtain its quasideterminant solutions by iterating its Darboux transformations. - Highlights: • Examples are given to illustrate the extensive applications of twisted derivations. • Bilinear Bäcklund transformation is constructed for the known q-2DTL equation. • Lax pair is obtained for an equivalent q-2DTL equation. • Quasideterminant solutions are found for the nc q-2DTL equation.

Two-dimensional critical phenomena

International Nuclear Information System (INIS)

Saleur, H.

1987-09-01

Two dimensional critical systems are studied using transformation to free fields and conformal invariance methods. The relations between the two approaches are also studied. The analytical results obtained generally depend on universality hypotheses or on renormalization group trajectories which are not established rigorously, so numerical verifications, mainly using the transfer matrix approach, are presented. The exact determination of critical exponents; the partition functions of critical models on toruses; and results as the critical point is approached are discussed [fr

EFL Published Materials: An Evaluation of English Textbooks for Junior High School in Indonesia

Directory of Open Access Journals (Sweden)

Rizaldy Hanifa

2018-04-01

Full Text Available The use of EFL published materials like textbooks are becoming more widespread as they can bring easiness in the classroom by providing teachers with guidelines comprised of syllabus, methodologies, as well as materials for teaching and learning. However, choosing a suitable textbook for their teaching situation is deemed to be one of the most challenging tasks that EFL teachers often face. To get a good picture of the suitability of a textbook, a careful investigation needs to be undertaken. This study focused on the analysis and evaluation of two different English textbooks addressed to junior high schools grade VII in Indonesia, KTSP and curriculum 2013 textbook. Harmer’s (2007 framework was employed to figure out the strengths and weaknesses of each textbook. The analysis revealed that both textbooks are quite satisfactory as they are very affordable, contain interesting layout, attractive designs, and clear instructions, correspond to current ELT methodology, cover all language skills, and comprise a wide range of topics which are familiar and culturally appropriate for learners. Nonetheless, the KTSP textbook does not have add-ons and extra materials; meanwhile, curriculum 2013 textbook is weak in providing authentic listening materials. Therefore, although the teachers manage to use the textbooks as their core materials, they are supposed to make adjustment and supplement them with other materials according to their learners’ needs and their teaching context.

A two-dimensional numerical study of the flow inside the combustion chamber of a motored rotary engine

Science.gov (United States)

Shih, T. I-P.; Yang, S. L.; Schock, H. J.

1986-01-01

A numerical study was performed to investigate the unsteady, multidimensional flow inside the combustion chambers of an idealized, two-dimensional, rotary engine under motored conditions. The numerical study was based on the time-dependent, two-dimensional, density-weighted, ensemble-averaged conservation equations of mass, species, momentum, and total energy valid for two-component ideal gas mixtures. The ensemble-averaged conservation equations were closed by a K-epsilon model of turbulence. This K-epsilon model of turbulence was modified to account for some of the effects of compressibility, streamline curvature, low-Reynolds number, and preferential stress dissipation. Numerical solutions to the conservation equations were obtained by the highly efficient implicit-factored method of Beam and Warming. The grid system needed to obtain solutions were generated by an algebraic grid generation technique based on transfinite interpolation. Results of the numerical study are presented in graphical form illustrating the flow patterns during intake, compression, gaseous fuel injection, expansion, and exhaust.

A two-dimensional numerical study of the flow inside the combustion chambers of a motored rotary engine

Science.gov (United States)

Shih, T. I. P.; Yang, S. L.; Schock, H. J.

1986-01-01

A numerical study was performed to investigate the unsteady, multidimensional flow inside the combustion chambers of an idealized, two-dimensional, rotary engine under motored conditions. The numerical study was based on the time-dependent, two-dimensional, density-weighted, ensemble-averaged conservation equations of mass, species, momentum, and total energy valid for two-component ideal gas mixtures. The ensemble-averaged conservation equations were closed by a K-epsilon model of turbulence. This K-epsilon model of turbulence was modified to account for some of the effects of compressibility, streamline curvature, low-Reynolds number, and preferential stress dissipation. Numerical solutions to the conservation equations were obtained by the highly efficient implicit-factored method of Beam and Warming. The grid system needed to obtain solutions were generated by an algebraic grid generation technique based on transfinite interpolation. Results of the numerical study are presented in graphical form illustrating the flow patterns during intake, compression, gaseous fuel injection, expansion, and exhaust.

A Study of Four Textbook Distribution Models

Science.gov (United States)

Graydon, Benjamin; Urbach-Buholz, Blake; Kohen, Cheryl

2011-01-01

Textbooks too often hinder rather than help students because of their prohibitively expensive prices. Colleges and universities facing intense pressure to lower education expenses while increasing access, retention, and achievement now find addressing the textbook problem more and more urgent. Used textbook sales have grown dramatically over the…

Do mathematics textbooks cultivate shallow teaching? Applying the TIMSS Video Study criteria to Australian eighth-grade mathematics textbooks

Science.gov (United States)

Vincent, Jill; Stacey, Kaye

2008-04-01

Australian eighth-grade mathematics lessons were shown by the 1999 TIMSS Video Study to use a high proportion of problems of low procedural complexity, with considerable repetition, and an absence of deductive reasoning. Using definitions from the Video Study, this study re-investigated this `shallow teaching syndrome' by examining the problems on three topics in nine eighth-grade textbooks from four Australian states for procedural complexity, type of solving processes, degree of repetition, proportion of `application' problems and proportion of problems requiring deductive reasoning. Overall, there was broad similarity between the characteristics of problems in the textbooks and in the Australian Video Study lessons. There were, however, considerable differences between textbooks and between topics within textbooks. In some books, including the best-selling textbooks in several states, the balance is too far towards repetitive problems of low procedural complexity.

Two-dimensional capillary origami

Energy Technology Data Exchange (ETDEWEB)

Brubaker, N.D., E-mail: nbrubaker@math.arizona.edu; Lega, J., E-mail: lega@math.arizona.edu

2016-01-08

We describe a global approach to the problem of capillary origami that captures all unfolded equilibrium configurations in the two-dimensional setting where the drop is not required to fully wet the flexible plate. We provide bifurcation diagrams showing the level of encapsulation of each equilibrium configuration as a function of the volume of liquid that it contains, as well as plots representing the energy of each equilibrium branch. These diagrams indicate at what volume level the liquid drop ceases to be attached to the endpoints of the plate, which depends on the value of the contact angle. As in the case of pinned contact points, three different parameter regimes are identified, one of which predicts instantaneous encapsulation for small initial volumes of liquid. - Highlights: • Full solution set of the two-dimensional capillary origami problem. • Fluid does not necessarily wet the entire plate. • Global energy approach provides exact differential equations satisfied by minimizers. • Bifurcation diagrams highlight three different regimes. • Conditions for spontaneous encapsulation are identified.

Two-dimensional capillary origami

International Nuclear Information System (INIS)

Brubaker, N.D.; Lega, J.

2016-01-01

We describe a global approach to the problem of capillary origami that captures all unfolded equilibrium configurations in the two-dimensional setting where the drop is not required to fully wet the flexible plate. We provide bifurcation diagrams showing the level of encapsulation of each equilibrium configuration as a function of the volume of liquid that it contains, as well as plots representing the energy of each equilibrium branch. These diagrams indicate at what volume level the liquid drop ceases to be attached to the endpoints of the plate, which depends on the value of the contact angle. As in the case of pinned contact points, three different parameter regimes are identified, one of which predicts instantaneous encapsulation for small initial volumes of liquid. - Highlights: • Full solution set of the two-dimensional capillary origami problem. • Fluid does not necessarily wet the entire plate. • Global energy approach provides exact differential equations satisfied by minimizers. • Bifurcation diagrams highlight three different regimes. • Conditions for spontaneous encapsulation are identified.

Dynamic burstiness of word-occurrence and network modularity in textbook systems

Science.gov (United States)

Cui, Xue-Mei; Yoon, Chang No; Youn, Hyejin; Lee, Sang Hoon; Jung, Jean S.; Han, Seung Kee

2017-12-01

We show that the dynamic burstiness of word occurrence in textbook systems is attributed to the modularity of the word association networks. At first, a measure of dynamic burstiness is introduced to quantify burstiness of word occurrence in a textbook. The advantage of this measure is that the dynamic burstiness is decomposable into two contributions: one coming from the inter-event variance and the other from the memory effects. Comparing network structures of physics textbook systems with those of surrogate random textbooks without the memory or variance effects are absent, we show that the network modularity increases systematically with the dynamic burstiness. The intra-connectivity of individual word representing the strength of a tie with which a node is bound to a module accordingly increases with the dynamic burstiness, suggesting individual words with high burstiness are strongly bound to one module. Based on the frequency and dynamic burstiness, physics terminology is classified into four categories: fundamental words, topical words, special words, and common words. In addition, we test the correlation between the dynamic burstiness of word occurrence and network modularity using a two-state model of burst generation.

Pragmatic Content in Global and Local ELT Textbooks

Directory of Open Access Journals (Sweden)

Hussein Meihami

2015-11-01

Full Text Available This study is an attempt to explore the frequency of pragmatic content occurrence represented as three speech acts of requesting, refusing, and apologizing in global and local English Language Teaching (ELT textbooks. Three global elementary ELT textbooks, namely Interchange, Top Notch, and American English File along with the local elementary textbooks of Iran Language Institute (ILI Series, were examined for their pragmatic content. To analyze the pragmatic content of these textbooks, the researchers used three different frameworks. The results indicated that while both global and local ELT textbooks shared a sufficient number of speech acts of request and refusal, they failed to pay enough attention to the speech act of apology regarding its frequency and the strategies through which it is performed. To sum, the findings of this study highlight the differences in the frequency of different speech acts and the strategies used to perform them in global and local elementary ELT textbooks, which bear some implications for ELT textbook developers and language instructors.

Two-dimensional black holes and non-commutative spaces

International Nuclear Information System (INIS)

Sadeghi, J.

2008-01-01

We study the effects of non-commutative spaces on two-dimensional black hole. The event horizon of two-dimensional black hole is obtained in non-commutative space up to second order of perturbative calculations. A lower limit for the non-commutativity parameter is also obtained. The observer in that limit in contrast to commutative case see two horizon

Textbook Graphics and Maps: Keys to Learning.

Science.gov (United States)

Danzer, Gerald A.

1980-01-01

Explains how social studies pupils can use an awareness of textbook design to become better students. Suggestions include reproducing the collage on an American history textbook as a large poster for classroom use and directing students to design a graphic unit opener in the same style as the ones in their textbooks. (DB)

Development of Open Textbooks Learning Analytics System

Science.gov (United States)

Prasad, Deepak; Totaram, Rajneel; Usagawa, Tsuyoshi

2016-01-01

Textbook costs have skyrocketed in recent years, putting them beyond the reach of many students, but there are options which can mitigate this problem. Open textbooks, an open educational resource, have proven capable of making textbooks affordable to students. There have been few educational development as promising as the development of open…

Two-dimensional Navier-Stokes turbulence in bounded domains

NARCIS (Netherlands)

Clercx, H.J.H.; van Heijst, G.J.F.

In this review we will discuss recent experimental and numerical results of quasi-two-dimensional decaying and forced Navier–Stokes turbulence in bounded domains. We will give a concise overview of developments in two-dimensional turbulence research, with emphasis on the progress made during the

Two-dimensional Navier-Stokes turbulence in bounded domains

NARCIS (Netherlands)

Clercx, H.J.H.; Heijst, van G.J.F.

2009-01-01

In this review we will discuss recent experimental and numerical results of quasi-two-dimensional decaying and forced Navier–Stokes turbulence in bounded domains. We will give a concise overview of developments in two-dimensional turbulence research, with emphasis on the progress made during the

Piezoelectricity in Two-Dimensional Materials

KAUST Repository

Wu, Tao; Zhang, Hua

2015-01-01

Powering up 2D materials: Recent experimental studies confirmed the existence of piezoelectricity - the conversion of mechanical stress into electricity - in two-dimensional single-layer MoS2 nanosheets. The results represent a milestone towards

Textbook-Caused Misconceptions, Inconsistencies, and Experimental Safety Risks of a Grade 8 Physics Textbook

Science.gov (United States)

Zajkov, Oliver; Gegovska-Zajkova, Sonja; Mitrevski, Boce

2017-01-01

A physics textbook for the 8th grade was analyzed, in particular the section on the interaction between electric current and magnetic field. The textbook is written in the Macedonian language, but is translated into Albanian, Serbian, and Turkish, which provides an opportunity to influence a larger population of children, in a larger ethnic area.…

A Framework for Open Textbooks Analytics System

Science.gov (United States)

Prasad, Deepak; Totaram, Rajneel; Usagawa, Tsuyoshi

2016-01-01

In the last few years, open textbook development has picked up dramatically due both to the expense of commercially published textbooks and the increasing availability of high-quality OER alternatives. While this offers a tremendous benefit in terms of lowering student textbook costs, the question remains, to what extent (if any) do open textbooks…

Introducing proportion in arithmetics domain: The case of current and historical textbooks: Papers from a doctoral course at the University of Copenhagen

DEFF Research Database (Denmark)

Wijayanti, Dyana

2015-01-01

One of the ways to analyse textbook is to trace back how such a mathematical content was explicated in a current and historical textbooks. The purpose of this study is to compare the explanation of proportion in three different textbooks from two different periods. By using praxeology, I analyse...... a current open online US textbook and two historical US textbooks. I describe how proportion is explained and appeared in examples and in exercises. The results show that each textbook has its own typical type of task and technique. I also observe that the way proportion is explained in current textbooks...... draws on what we could call ‘daily life situations’ while the historical textbooks use a more formal definition. Furthermore, I find that the historical textbooks provide more algebraic approaches to discuss property of proportion while the current textbook gives advantage for students to have more than...

Solution of the two-dimensional spectral factorization problem

Science.gov (United States)

Lawton, W. M.

1985-01-01

An approximation theorem is proven which solves a classic problem in two-dimensional (2-D) filter theory. The theorem shows that any continuous two-dimensional spectrum can be uniformly approximated by the squared modulus of a recursively stable finite trigonometric polynomial supported on a nonsymmetric half-plane.

But What Does It Look Like? Illustrations of Disciplinary Literacy Teaching in Two Content Areas

Science.gov (United States)

Rainey, Emily C.; Maher, Bridget L.; Coupland, David; Franchi, Rod; Moje, Elizabeth Birr

2018-01-01

In this piece, the authors offer two illustrations of central features of disciplinary literacy teaching. One illustration describes an episode of history literacy teaching, and the other describes an episode of physics literacy teaching. Both examples show how teachers may support students' development of disciplinary inquiry, disciplinary…

Textbooks evaluations in the National Textbook Commission: the school knowledge conformation in the 1940’s

Directory of Open Access Journals (Sweden)

Juliana Miranda Filgueiras

2013-05-01

Full Text Available This article analyzes the textbooks evaluations, performed during the 1940’s, and the relationship with the school knowledge conformation. The schoolbook policy was promulgated by Law n. 1.006/38, which created the National Textbook Commission (CNLD, responsible for examining and authorizing the textbooks to be adopted across the country. We tried to discuss the Commission constitution, understand who its members were and the work those people developed, focusing on the study of the textbooks evaluations. The analysis highlighted the conflicts between the people involved in those evaluations, who were trying to update the contents and teaching methods in accordance with the official programs and scientific research areas, as well as seeking an official spelling conform for the whole country.

Syntactical Analysis of Economics Textbooks.

Science.gov (United States)

Wilcox, George K.

An analysis of the syntax of economics textbooks was undertaken to (1) provide real-language examples of the difficult grammatical structures being taught in an advanced economics reading course, and (2) construct a factual database of the nature of economics textbooks. Five texts representative of those typically used in introductory economics…

Development of Two-Dimensional NMR

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 20; Issue 11. Development of Two-Dimensional NMR: Strucure Determination of Biomolecules in Solution. Anil Kumar. General Article Volume 20 Issue 11 November 2015 pp 995-1002 ...

ONE-DIMENSIONAL AND TWO-DIMENSIONAL LEADERSHIP STYLES

OpenAIRE

Nikola Stefanović

2007-01-01

In order to motivate their group members to perform certain tasks, leaders use different leadership styles. These styles are based on leaders' backgrounds, knowledge, values, experiences, and expectations. The one-dimensional styles, used by many world leaders, are autocratic and democratic styles. These styles lie on the two opposite sides of the leadership spectrum. In order to precisely define the leadership styles on the spectrum between the autocratic leadership style and the democratic ...

Linear Port-Hamiltonian Systems on Infinite-dimensional Spaces

CERN Document Server

Jacob, Birgit

2012-01-01

This book provides a self-contained introduction to the theory of infinite-dimensional systems theory and its applications to port-Hamiltonian systems. The textbook starts with elementary known results, then progresses smoothly to advanced topics in current research. Many physical systems can be formulated using a Hamiltonian framework, leading to models described by ordinary or partial differential equations. For the purpose of control and for the interconnection of two or more Hamiltonian systems it is essential to take into account this interaction with the environment. This book is the fir

Infrared magneto-spectroscopy of two-dimensional and three-dimensional massless fermions: A comparison

Energy Technology Data Exchange (ETDEWEB)

Orlita, M., E-mail: milan.orlita@lncmi.cnrs.fr [Laboratoire National des Champs Magnétiques Intenses, CNRS-UJF-UPS-INSA, 38042 Grenoble (France); Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 121 16 Prague 2 (Czech Republic); Faugeras, C.; Barra, A.-L.; Martinez, G.; Potemski, M. [Laboratoire National des Champs Magnétiques Intenses, CNRS-UJF-UPS-INSA, 38042 Grenoble (France); Basko, D. M. [LPMMC UMR 5493, Université Grenoble 1/CNRS, B.P. 166, 38042 Grenoble (France); Zholudev, M. S. [Laboratoire Charles Coulomb (L2C), UMR CNRS 5221, GIS-TERALAB, Université Montpellier II, 34095 Montpellier (France); Institute for Physics of Microstructures, RAS, Nizhny Novgorod GSP-105 603950 (Russian Federation); Teppe, F.; Knap, W. [Laboratoire Charles Coulomb (L2C), UMR CNRS 5221, GIS-TERALAB, Université Montpellier II, 34095 Montpellier (France); Gavrilenko, V. I. [Institute for Physics of Microstructures, RAS, Nizhny Novgorod GSP-105 603950 (Russian Federation); Mikhailov, N. N.; Dvoretskii, S. A. [A.V. Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090 (Russian Federation); Neugebauer, P. [Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany); Berger, C. [School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Institut Néel/CNRS-UJF BP 166, F-38042 Grenoble Cedex 9 (France); Heer, W. A. de [School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

2015-03-21

Here, we report on a magneto-optical study of two distinct systems hosting massless fermions—two-dimensional graphene and three-dimensional HgCdTe tuned to the zero band gap condition at the point of the semiconductor-to-semimetal topological transition. Both materials exhibit, in the quantum regime, a fairly rich magneto-optical response, which is composed from a series of intra- and interband inter-Landau level resonances with for massless fermions typical √(B) dependence. The impact of the system's dimensionality and of the strength of the spin-orbit interaction on the optical response is also discussed.

Densis. Densimetric representation of two-dimensional matrices

International Nuclear Information System (INIS)

Los Arcos Merino, J.M.

1978-01-01

Densis is a Fortran V program which allows off-line control of a Calcomp digital plotter, to represent a two-dimensional matrix of numerical elements in the form of a variable shading intensity map in two colours. Each matrix element is associated to a square of a grid which is traced over by lines whose number is a function of the element value according to a selected scale. Program features, subroutine structure and running instructions, are described. Some typical results, for gamma-gamma coincidence experimental data and a sampled two-dimensional function, are indicated. (author)

Europe representations in textbooks

OpenAIRE

Brennetot , Arnaud

2011-01-01

This EuroBroadMap working paper presents an analysis of textbooks dealing with the representations of Europe and European Union. In most of these textbooks from secondary school, the teaching of the geography of Europe precedes the evocation of the EU. Europe is often depicted as a given object, reduced to a number of structural aspects (relief, climate, demography, traditional cultures, economic activities, etc.) whose only common point is their location within conventional boundaries. Such ...

Posology of insulins: A review of standard textbooks and product inserts

Directory of Open Access Journals (Sweden)

Garima Bhutani

2015-01-01

Full Text Available Objectives: The study is aimed to assess whether the information contained in standard pharmacology, endocrinology, and diabetology textbooks regarding timings of administration, frequency and dose of various insulins is adequate and also to see whether the information contained in these texts is concordant with product inserts. Materials and Methods: Four standard textbooks of pharmacology, two of diabetology and three of endocrinology were assessed for the published information regarding dose, timing, and frequency of insulin administration. The product inserts of commonly available insulins in India were also studied for the same. Results: Various omissions and disparities could be seen in the coverage of insulins in standard textbooks. Posology information about premixed insulins and basal insulins have been omitted by the majority of the textbooks. Details about dose, frequency and timings of ultra-short acting insulins have also not been covered by all textbooks. Some discrepancies regarding prescribing information was also noted in product inserts, especially in case of newer insulins. Conclusions: Thus, this article stresses upon the need of a uniform source of information for providing adequate and standardized knowledge regarding timing, frequency, and dose of insulins.

Resonance fluorescence based two- and three-dimensional atom localization

Science.gov (United States)

Wahab, Abdul; Rahmatullah; Qamar, Sajid

2016-06-01

Two- and three-dimensional atom localization in a two-level atom-field system via resonance fluorescence is suggested. For the two-dimensional localization, the atom interacts with two orthogonal standing-wave fields, whereas for the three-dimensional atom localization, the atom interacts with three orthogonal standing-wave fields. The effect of the detuning and phase shifts associated with the corresponding standing-wave fields is investigated. A precision enhancement in position measurement of the single atom can be noticed via the control of the detuning and phase shifts.

Genocide in World History Textbooks.

Science.gov (United States)

Fleming, Dan

1987-01-01

Analyzes the treatment of genocide in secondary world history textbooks. Acknowledges that textbook space is limited, but argues that all should contain some reference to the subject. Concludes that the Armenian genocide, as well as the genocidal acts of Hitler, Stalin, and Mao Tse-tung should be presented in all survey texts. (GEA)

Toward two-dimensional search engines

International Nuclear Information System (INIS)

Ermann, L; Shepelyansky, D L; Chepelianskii, A D

2012-01-01

We study the statistical properties of various directed networks using ranking of their nodes based on the dominant vectors of the Google matrix known as PageRank and CheiRank. On average PageRank orders nodes proportionally to a number of ingoing links, while CheiRank orders nodes proportionally to a number of outgoing links. In this way, the ranking of nodes becomes two dimensional which paves the way for the development of two-dimensional search engines of a new type. Statistical properties of information flow on the PageRank–CheiRank plane are analyzed for networks of British, French and Italian universities, Wikipedia, Linux Kernel, gene regulation and other networks. A special emphasis is done for British universities networks using the large database publicly available in the UK. Methods of spam links control are also analyzed. (paper)

Subjective figure reversal in two- and three-dimensional perceptual space.

Science.gov (United States)

Radilová, J; Radil-Weiss, T

1984-08-01

A permanently illuminated pattern of Mach's truncated pyramid can be perceived according to the experimental instruction given, either as a three-dimensional reversible figure with spontaneously changing convex and concave interpretation (in one experiment), or as a two-dimensional reversible figure-ground pattern (in another experiment). The reversal rate was about twice as slow, without the subjects being aware of it, if it was perceived as a three-dimensional figure compared to the situation when it was perceived as two-dimensional. It may be hypothetized that in the three-dimensional case, the process of perception requires more sequential steps than in the two-dimensional one.

TEXTBOOK ANALYSIS IN THE SERVICE OF CHEMISTRY TEACHING

Directory of Open Access Journals (Sweden)

Aija Ahtineva

2005-06-01

Full Text Available The authors of textbooks have their own visions of contents and teaching methods, which should lead to a high level of scientific thinking. However, the textbook alone does not guarantee good results because the personal and social relationships between the teacher and students have a major influence on teaching and learning. Therefore, the teacher’s study of the textbook before teaching facilitates the teaching process. This paper suggests one method of textbook analysis. In the analysis, one upper secondary level course of chemistry instruction involved the use of a learning strategy: classification of the central concepts and a classification of activities based on task difficulty. The study also attempted to find out the goodness of fit between the national curriculum and the textbook chemistry course. The national objectives concerned the content of knowledge, social significance, emphasis on experimental chemistry, and inspiring students for further study. The majority of the textbook tasks fall into higher order categories characterized by knowledge structures assuming application of knowledge or making inferences. Good textbook activities also have social significance, and a number of experimental tasks are included. The textbook quality is further enhanced by up-to-date content. All of the above qualities are related to high study motivation.

Comparison of ethanol-soluble proteins from different rye (Secale cereale) varieties by two-dimensional electrophoresis

DEFF Research Database (Denmark)

Radzikowski, Louise; Nesic, Ljiljana; Hansen, H.B.

2002-01-01

The major storage proteins from six rye varieties, grown under the same conditions in 1997 and 1998 in Ronhave, Denmark, were analyzed by two-dimensional (2-D) polyacrylamide gel electrophoresis. The proteins were extracted from ground rye kernels with 70% ethanol and separated by 2-D electrophor......The major storage proteins from six rye varieties, grown under the same conditions in 1997 and 1998 in Ronhave, Denmark, were analyzed by two-dimensional (2-D) polyacrylamide gel electrophoresis. The proteins were extracted from ground rye kernels with 70% ethanol and separated by 2-D...... electrophoresis. The gels were scanned, compared using ImageMaster(R) software and the data sets were analyzed by principal component analysis (PCA) using THE UNSCRAMBLER software. Afterwards MATLAB was used to make a cluster analysis of the varieties based on PCA. The analysis of the gels showed...... separately. When the results were combined from the two years five varieties could be differentiated. The results from the PCA confirmed the finding of the unique spots and cluster analysis was made in order to illustrate the results. The combination of the results from 2-D electrophoresis and other grain...

Understanding European education landscape on natural disasters - a textbook research

Science.gov (United States)

Komac, B.; Zorn, M.; Ciglič, R.; Steinführer, A.

2012-04-01

The importance of natural-disaster education for social preparedness is presented. Increasing damage caused by natural disasters around the globe draws attention to the fact that even developed societies must adapt to natural processes. Natural-disaster education is a component part of any education strategy for a sustainably oriented society. The purpose of this article is to present the role of formal education in natural disasters in Europe. To ensure a uniform overview, the study used secondary-school geography textbooks from the collection at the Georg Eckert Institute for International Textbook Research in Braunschweig, Germany. Altogether, nearly 190 textbooks from 35 European countries were examined. The greatest focus on natural disasters can be found in textbooks published in western Europe (3.8% of pages describing natural disasters), and the smallest in those published in eastern Europe (0.7%). A share of textbook pages exceeding three percent describing natural disasters can also be found in northern Europe (3.6%) and southeast Europe, including Turkey (3.4%). The shares in central and southern Europe exceed two percent (i.e., 2.8% and 2.3%, respectively). The types and specific examples of natural disasters most commonly covered in textbooks as well as the type of natural disasters presented in textbooks according to the number of casualties and the damage caused were analyzed. The results show that the majority of European (secondary-school) education systems are poorly developed in terms of natural-disaster education. If education is perceived as part of natural-disaster management and governance, greater attention should clearly be dedicated to this activity. In addition to formal education, informal education also raises a series of questions connected with the importance of this type of education. Special attention was drawn to the importance of knowledge that locals have about their region because this aspect of education is important in both

The Limits of Master Narratives in History Textbooks: An Analysis of Representations of Martin Luther King, Jr.

Science.gov (United States)

Alridge, Derrick P.

2006-01-01

In this study, I argue that American history textbooks present discrete, heroic, one-dimensional, and neatly packaged master narratives that deny students a complex, realistic, and rich understanding of people and events in American history. In making this argument, I examine the master narratives of Martin Luther King, Jr., in high school history…

Two multi-dimensional uncertainty relations

International Nuclear Information System (INIS)

Skala, L; Kapsa, V

2008-01-01

Two multi-dimensional uncertainty relations, one related to the probability density and the other one related to the probability density current, are derived and discussed. Both relations are stronger than the usual uncertainty relations for the coordinates and momentum

Textbook Religion and Lived Religion: A Comparison of the Christian Faith as Expressed in Textbooks and by Young Church Members

Science.gov (United States)

Vestøl, Jon Magne

2016-01-01

Drawing on perspectives from sociocultural theory, this article investigates how Christian denominations are represented in Norwegian textbooks of religious education and by young believers. The main finding is that textbooks and young adherents present religion in substantially different ways. While textbooks relate religion to global and…

Mechanical exfoliation of two-dimensional materials

Science.gov (United States)

Gao, Enlai; Lin, Shao-Zhen; Qin, Zhao; Buehler, Markus J.; Feng, Xi-Qiao; Xu, Zhiping

2018-06-01

Two-dimensional materials such as graphene and transition metal dichalcogenides have been identified and drawn much attention over the last few years for their unique structural and electronic properties. However, their rise begins only after these materials are successfully isolated from their layered assemblies or adhesive substrates into individual monolayers. Mechanical exfoliation and transfer are the most successful techniques to obtain high-quality single- or few-layer nanocrystals from their native multi-layer structures or their substrate for growth, which involves interfacial peeling and intralayer tearing processes that are controlled by material properties, geometry and the kinetics of exfoliation. This procedure is rationalized in this work through theoretical analysis and atomistic simulations. We propose a criterion to assess the feasibility for the exfoliation of two-dimensional sheets from an adhesive substrate without fracturing itself, and explore the effects of material and interface properties, as well as the geometrical, kinetic factors on the peeling behaviors and the torn morphology. This multi-scale approach elucidates the microscopic mechanism of the mechanical processes, offering predictive models and tools for the design of experimental procedures to obtain single- or few-layer two-dimensional materials and structures.

Nursing Student Perceptions of Digital Textbooks: A Pilot Study.

Science.gov (United States)

Mennenga, Heidi A

2016-01-01

Digital textbooks are increasing in popularity, often resulting from the perception that students demand the use of technology in academics. However, few studies have been done on student perceptions of digital textbooks. A pilot study was conducted with students enrolled in a nursing research course; 123 nursing students participated. This study found that students overwhelmingly preferred print textbooks over digital textbooks. More research needs to be done before assuming students would prefer digital textbooks over print.

Popular Science: Introductory Physics Textbooks for Home Economics Students

Science.gov (United States)

Behrman, Joanna

2014-03-01

For many decades now there has been an ongoing debate about the way and extent to which physics ought to be popularized by appealing to a student's every day experience. Part of this debate has focused on how textbooks, a major factor shaping students' education, ought to be written and presented. I examine the background, passages, and problems of two examples drawn from the special genre of ``Household Physics'' textbooks which were published largely between 1910 and 1940. The pedagogy of applying or relating physics to the everyday experience engenders values defining how and by whom science is to be applied. These books are particularly evocative, as well, of the extent to which gender can be tied to differing everyday experiences and the consequences therefore of using experiential examples. Using popular science textbooks can alienate students by drawing an implicit division between the reader and the practicing scientist.

Identifying User Interaction Patterns in E-Textbooks.

Science.gov (United States)

Saarinen, Santeri; Heimonen, Tomi; Turunen, Markku; Mikkilä-Erdmann, Mirjamaija; Raisamo, Roope; Erdmann, Norbert; Yrjänäinen, Sari; Keskinen, Tuuli

2015-01-01

We introduce a new architecture for e-textbooks which contains two navigational aids: an index and a concept map. We report results from an evaluation in a university setting with 99 students. The interaction sequences of the users were captured during the user study. We found several clusters of user interaction types in our data. Three separate user types were identified based on the interaction sequences: passive user, term clicker, and concept map user. We also discovered that with the concept map interface users started to interact with the application significantly sooner than with the index interface. Overall, our findings suggest that analysis of interaction patterns allows deeper insights into the use of e-textbooks than is afforded by summative evaluation.

Introductory Business Textbook Revision Cycles: Are They Getting Shorter?

Science.gov (United States)

Zinser, Brian; Brunswick, Gary

2010-01-01

The rate of textbook revision cycles is examined in light of the recent trend towards more rapid revisions (and adoptions of textbooks). The authors conduct background research to better understand the context for textbook revision cycles and the environmental forces that have been influencing what appears to be more rapid textbook revisions. A…

Asymptotics for Two-dimensional Atoms

DEFF Research Database (Denmark)

Nam, Phan Thanh; Portmann, Fabian; Solovej, Jan Philip

2012-01-01

We prove that the ground state energy of an atom confined to two dimensions with an infinitely heavy nucleus of charge $Z>0$ and $N$ quantum electrons of charge -1 is $E(N,Z)=-{1/2}Z^2\\ln Z+(E^{\\TF}(\\lambda)+{1/2}c^{\\rm H})Z^2+o(Z^2)$ when $Z\\to \\infty$ and $N/Z\\to \\lambda$, where $E^{\\TF}(\\lambd......We prove that the ground state energy of an atom confined to two dimensions with an infinitely heavy nucleus of charge $Z>0$ and $N$ quantum electrons of charge -1 is $E(N,Z)=-{1/2}Z^2\\ln Z+(E^{\\TF}(\\lambda)+{1/2}c^{\\rm H})Z^2+o(Z^2)$ when $Z\\to \\infty$ and $N/Z\\to \\lambda$, where $E......^{\\TF}(\\lambda)$ is given by a Thomas-Fermi type variational problem and $c^{\\rm H}\\approx -2.2339$ is an explicit constant. We also show that the radius of a two-dimensional neutral atom is unbounded when $Z\\to \\infty$, which is contrary to the expected behavior of three-dimensional atoms....

Breastfeeding information in pharmacology textbooks: a content analysis.

Science.gov (United States)

Amir, Lisa H; Raval, Manjri; Hussainy, Safeera Y

2013-07-01

Women often need to take medicines while breastfeeding and pharmacists need to provide accurate information in order to avoid undue caution about the compatibility of medicines and breastfeeding. The objective of this study was to review information provided about breastfeeding in commonly used pharmacology textbooks. We asked 15 Australian universities teaching pharmacy courses to provide a list of recommended pharmacology textbooks in 2011. Ten universities responded, generating a list of 11 textbooks that we analysed for content relating to breastfeeding. Pharmacology textbooks outline the mechanisms of actions of medicines and their use: however, only a small emphasis is placed on the safety/compatibility of medicines for women during breastfeeding. Current pharmacology textbooks recommended by Australian universities have significant gaps in their coverage of medicine use in breastfeeding. Authors of textbooks should address this gap, so academic staff can recommend texts with the best lactation content.

Can Tech Transcend the Textbook?

Science.gov (United States)

Waters, John K.

2011-01-01

After traveling a long, tortuous road, the much-anticipated e-book revolution has finally arrived. So where is the revolution in the "e-textbook" market? According to the National Association of College Stores (NACS), digital books currently account for less than 3 percent of textbook sales. NACS expects that percentage to reach 10 to 15 percent…

A Two-dimensional Version of the Niblett-Bostick Transformation for Magnetotelluric Interpretations

Science.gov (United States)

Esparza, F.

2005-05-01

An imaging technique for two-dimensional magnetotelluric interpretations is developed following the well known Niblett-Bostick transformation for one-dimensional profiles. The algorithm uses a Hopfield artificial neural network to process series and parallel magnetotelluric impedances along with their analytical influence functions. The adaptive, weighted average approximation preserves part of the nonlinearity of the original problem. No initial model in the usual sense is required for the recovery of a functional model. Rather, the built-in relationship between model and data considers automatically, all at the same time, many half spaces whose electrical conductivities vary according to the data. The use of series and parallel impedances, a self-contained pair of invariants of the impedance tensor, avoids the need to decide on best angles of rotation for TE and TM separations. Field data from a given profile can thus be fed directly into the algorithm without much processing. The solutions offered by the Hopfield neural network correspond to spatial averages computed through rectangular windows that can be chosen at will. Applications of the algorithm to simple synthetic models and to the COPROD2 data set illustrate the performance of the approximation.

The Concept of the Interculture in Time: (Intercultural Topics in Textbooks of French as a Foreign Language

Directory of Open Access Journals (Sweden)

Meta Lah

2012-12-01

Full Text Available The article deals with the concept of interculturality as used in foreign language didactics. In accordance with the definition of interculturality given in the first part of the article, two categories are included in the analysis – two “levels” of culture, each of them bearing a different name in literature, namely high and popular culture. Various textbooks used for teaching French as a foreign language in Slovenia in both the past and present were chosen for the analysis of topics that cover a fairly long period of time – among them the textbooks by two Slovenian authors: Južnič (1938 and Grad (1954, as well as some generally-used French textbooks, such as Cours de langue et de civilisation françaises (1953, Le nouveau sans frontières (1988 and Nouveau rond point (2011. The article is based on the hypothesis that high culture is more likely to be present in the older textbooks, which are based on traditional methods, whereas in modern textbooks more popular, everyday topics can be found. It is also presumed that topics in modern textbooks are, compared to their more traditional counterparts, introduced in an intercultural manner which could encourage students to compare the culture of the foreign country with their own. Both hypotheses are partly confirmed. In Slovenian textbooks there are very few culture-based topics. On the other hand, they are present in all French textbooks, regardless of the methodology. It is true that Mauger introduces more high culture than the others and that the intercultural topics are presented only in the most recent textbook. In all the others, it is exclusively the culture of the target country that is introduced.

Establishing and Applying Literature-Based Criteria for Effective Communication of Science to Novices via Introductory Geology Textbooks

Science.gov (United States)

Kortz, Karen M.; Grenga, Andrea M.; Smay, Jessica J.

2017-01-01

Textbooks are widely used in higher education by instructors and students. Therefore, it is useful to examine how textbooks present information because textbook design impacts how well students learn from them. This study has two parts. First, within the framework of the cognitive load and dual-coding theories, a set of recommendations based on…

Spin dynamics in a two-dimensional quantum gas

DEFF Research Database (Denmark)

Pedersen, Poul Lindholm; Gajdacz, Miroslav; Deuretzbacher, Frank

2014-01-01

We have investigated spin dynamics in a two-dimensional quantum gas. Through spin-changing collisions, two clouds with opposite spin orientations are spontaneously created in a Bose-Einstein condensate. After ballistic expansion, both clouds acquire ring-shaped density distributions with superimp......We have investigated spin dynamics in a two-dimensional quantum gas. Through spin-changing collisions, two clouds with opposite spin orientations are spontaneously created in a Bose-Einstein condensate. After ballistic expansion, both clouds acquire ring-shaped density distributions...

E-Books or Textbooks: Students Prefer Textbooks

Science.gov (United States)

Woody, William Douglas; Daniel, David B.; Baker, Crystal A.

2010-01-01

Previous research has demonstrated that the experience of reading e-books is not equivalent to reading textbooks. This study examines factors influencing preference for e-books as well as reported use of e-book content. Although the present student cohort is the most technologically savvy to ever enter universities, students do not prefer e-books…

Textbooks and citizenship education

OpenAIRE

Freitas, Maria Luísa Amaral Varela de

2000-01-01

This paper relates an investigation that tries to listen to children's voices about the social studies textbooks they would like to use the following year. It was developed in nine elementary classrooms. Children answered an open question, in a written form, about what they liked and disliked in their textbooks. They were then asked to select three pages they liked and three they did not like, and give reasons. The children loved this particular task. I did not have an explicit hypothesis but...

Procedures for two-dimensional electrophoresis of proteins

Energy Technology Data Exchange (ETDEWEB)

Tollaksen, S.L.; Giometti, C.S.

1996-10-01

High-resolution two-dimensional gel electrophoresis (2DE) of proteins, using isoelectric focusing in the first dimension and sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS-PAGE) in the second, was first described in 1975. In the 20 years since those publications, numerous modifications of the original method have evolved. The ISO-DALT system of 2DE is a high-throughput approach that has stood the test of time. The problem of casting many isoelectric focusing gels and SDS-PAGE slab gels (up to 20) in a reproducible manner has been solved by the use of the techniques and equipment described in this manual. The ISO-DALT system of two-dimensional gel electrophoresis originated in the late 1970s and has been modified many times to improve its high-resolution, high-throughput capabilities. This report provides the detailed procedures used with the current ISO-DALT system to prepare, run, stain, and photograph two-dimensional gels for protein analysis.

Quantum oscillations in quasi-two-dimensional conductors

CERN Document Server

Galbova, O

2002-01-01

The electronic absorption of sound waves in quasi-two-dimensional conductors in strong magnetic fields, is investigated theoretically. A longitudinal acoustic wave, propagating along the normal n-> to the layer of quasi-two-dimensional conductor (k-> = left brace 0,0,k right brace; u-> = left brace 0,0,u right brace) in magnetic field (B-> = left brace 0, 0, B right brace), is considered. The quasiclassical approach for this geometry is of no interest, due to the absence of interaction between electromagnetic and acoustic waves. The problem is of interest in strong magnetic field when quantization of the charge carriers energy levels takes place. The quantum oscillations in the sound absorption coefficient, as a function of the magnetic field, are theoretically observed. The experimental study of the quantum oscillations in quasi-two-dimensional conductors makes it possible to solve the inverse problem of determining from experimental data the extrema closed sections of the Fermi surface by a plane p sub z = ...

Third sound in one and two dimensional modulated structures

International Nuclear Information System (INIS)

Komuro, T.; Kawashima, H., Shirahama, K.; Kono, K.

1996-01-01

An experimental technique is developed to study acoustic transmission in one and two dimensional modulated structures by employing third sound of a superfluid helium film. In particular, the Penrose lattice, which is a two dimensional quasiperiodic structure, is studied. In two dimensions, the scattering of third sound is weaker than in one dimension. Nevertheless, the authors find that the transmission spectrum in the Penrose lattice, which is a two dimensional prototype of the quasicrystal, is observable if the helium film thickness is chosen around 5 atomic layers. The transmission spectra in the Penrose lattice are explained in terms of dynamical theory of diffraction

The approach to sexuality in PNLD textbooks: a focus on STI/AIDS and condoms

Directory of Open Access Journals (Sweden)

Célia de Souza Ladislau Filha

Full Text Available Abstract The patent contents in textbooks are selected according to the scientific knowledge (K, values (V and social practice (P. These three variables are the elements of the educational model, KVP, developed by Clément. The aim of this study was to analyze the Sexual Education approach on textbooks, relating to STD/AIDS and condoms in 15 8th grade Science textbooks, distributed in Brazil by PNLD in 2014. The data were collected based on two analytical matrices constructed within the European Biohead-Citizen Project and analyzed using the KVP model. The results show that despite the small improvement in the type of image present in textbooks, human bodies are still presented in a sectional shape and the images found are not very enlightening regarding sexual intercourse. As for the educational style textual content, only two books were classified in informative and participative category, aspect that indicates limitations on the openness to dialogue about sexuality in most of the analyzed books.

Two-dimensional membranes in motion

NARCIS (Netherlands)

Davidovikj, D.

2018-01-01

This thesis revolves around nanomechanical membranes made of suspended two - dimensional materials. Chapters 1-3 give an introduction to the field of 2D-based nanomechanical devices together with an overview of the underlying physics and the measurementtools used in subsequent chapters. The research

Large Scale Parallel DNA Detection by Two-Dimensional Solid-State Multipore Systems.

Science.gov (United States)

Athreya, Nagendra Bala Murali; Sarathy, Aditya; Leburton, Jean-Pierre

2018-04-23

We describe a scalable device design of a dense array of multiple nanopores made from nanoscale semiconductor materials to detect and identify translocations of many biomolecules in a massively parallel detection scheme. We use molecular dynamics coupled to nanoscale device simulations to illustrate the ability of this device setup to uniquely identify DNA parallel translocations. We show that the transverse sheet currents along membranes are immune to the crosstalk effects arising from simultaneous translocations of biomolecules through multiple pores, due to their ability to sense only the local potential changes. We also show that electronic sensing across the nanopore membrane offers a higher detection resolution compared to ionic current blocking technique in a multipore setup, irrespective of the irregularities that occur while fabricating the nanopores in a two-dimensional membrane.

English Textbooks in Parallel-Language Tertiary Education

OpenAIRE

Pecorari, D.; Shaw, P.; Irvine, Aileen; Malmstrom, H.

2011-01-01

Tertiary education in many countries is increasingly bilingual, with English used in parallel with the national language, particularly as a reading language. This article describes the results of a survey of student attitudes toward, and reading practices regarding, English language textbooks. Over 1,000 students at three Swedish universities responded to a questionnaire asking about their experiences with English textbooks. Textbooks written in English were generally unpopular, and the perce...

High Textbook Reading Rates When Using an Interactive Textbook for a Material and Energy Balances Course

Science.gov (United States)

Liberatore, Matthew

2017-01-01

Textbooks are experiencing a 21st century makeover. The author has created a web-based electronic textbook, Material and Energy Balances zyBook, that records students' interactions. Animations and question sets create interactive and scaffolded content. The interactive format is adopted successfully in other engineering disciplines and is now…

HEXAGA-II-120, -60, -30 two-dimensional multi-group neutron diffusion programmes for a uniform triangular mesh with arbitrary group scattering

International Nuclear Information System (INIS)

Woznicki, Z.

1979-06-01

This report presents the AGA two-sweep iterative methods belonging to the family of factorization techniques in their practical application in the HEXAGA-II two-dimensional programme to obtain the numerical solution to the multi-group, time-independent, (real and/or adjoint) neutron diffusion equations for a fine uniform triangular mesh. An arbitrary group scattering model is permitted. The report written for the users provides the description of input and output. The use of HEXAGA-II is illustrated by two sample reactor problems. (orig.) [de

Incorrectness of conventional one-dimensional parallel thermal resistance circuit model for two-dimensional circular composite pipes

International Nuclear Information System (INIS)

Wong, K.-L.; Hsien, T.-L.; Chen, W.-L.; Yu, S.-J.

2008-01-01

This study is to prove that two-dimensional steady state heat transfer problems of composite circular pipes cannot be appropriately solved by the conventional one-dimensional parallel thermal resistance circuits (PTRC) model because its interface temperatures are not unique. Thus, the PTRC model is definitely different from its conventional recognized analogy, parallel electrical resistance circuits (PERC) model, which has unique node electric voltages. Two typical composite circular pipe examples are solved by CFD software, and the numerical results are compared with those obtained by the PTRC model. This shows that the PTRC model generates large error. Thus, this conventional model, introduced in most heat transfer text books, cannot be applied to two-dimensional composite circular pipes. On the contrary, an alternative one-dimensional separately series thermal resistance circuit (SSTRC) model is proposed and applied to a two-dimensional composite circular pipe with isothermal boundaries, and acceptable results are returned

Chiral anomaly, fermionic determinant and two dimensional models

International Nuclear Information System (INIS)

Rego Monteiro, M.A. do.

1985-01-01

The chiral anomaly in random pair dimension is analysed. This anomaly is perturbatively calculated by dimensional regularization method. A new method for non-perturbative Jacobian calculation of a general chiral transformation, 1.e., finite and non-Abelian, is developed. This method is used for non-perturbative chiral anomaly calculation, as an alternative to bosonization of two-dimensional theories for massless fermions and to study the phenomenum of fermion number fractionalization. The fermionic determinant from two-dimensional quantum chromodynamics is also studied, and calculated, exactly, as in decoupling gauge as with out reference to a particular gauge. (M.C.K.) [pt

A two-dimensional Zn coordination polymer with a three-dimensional supramolecular architecture

Directory of Open Access Journals (Sweden)

Fuhong Liu

2017-10-01

Full Text Available The title compound, poly[bis{μ2-4,4′-bis[(1,2,4-triazol-1-ylmethyl]biphenyl-κ2N4:N4′}bis(nitrato-κOzinc(II], [Zn(NO32(C18H16N62]n, is a two-dimensional zinc coordination polymer constructed from 4,4′-bis[(1H-1,2,4-triazol-1-ylmethyl]-1,1′-biphenyl units. It was synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. The ZnII cation is located on an inversion centre and is coordinated by two O atoms from two symmetry-related nitrate groups and four N atoms from four symmetry-related 4,4′-bis[(1H-1,2,4-triazol-1-ylmethyl]-1,1′-biphenyl ligands, forming a distorted octahedral {ZnN4O2} coordination geometry. The linear 4,4′-bis[(1H-1,2,4-triazol-1-ylmethyl]-1,1′-biphenyl ligand links two ZnII cations, generating two-dimensional layers parallel to the crystallographic (132 plane. The parallel layers are connected by C—H...O, C—H...N, C—H...π and π–π stacking interactions, resulting in a three-dimensional supramolecular architecture.

Atomic resolution holography using advanced reconstruction techniques for two-dimensional detectors

Energy Technology Data Exchange (ETDEWEB)

Marko, M; Szakal, A; Cser, L [Neutron Spectroscopy Department, Research Institute for Solid State Physics and Optics, PO Box 49, H-1525 Budapest (Hungary); Krexner, G [Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna (Austria); Schefer, J, E-mail: marko@szfki.h [Laboratory for Neutron Scattering (LNS), Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)

2010-06-15

Atomic resolution holography is based on two concepts. Either the emitter of the radiation used is embedded in the sample (internal source concept) or, on account of the optical reciprocity law, the detector forms part of the sample (internal detector concept). In many cases, holographic objects (atoms and nuclei) simultaneously adopt the roles of both source and detector. Thus, the recorded image contains a mixture of both inside source and inside detector holograms. When reconstructing one type of hologram, the presence of the other hologram causes serious distortions. In the present work, we propose a new method, the so-called double reconstruction (DR), which not only suppresses the mutual distortions but also exploits the information content of the measured hologram more effectively. This novel approach also decreases the level of distortion arising from diffraction and statistical noise. The efficiency of the DR technique is significantly enhanced by employing two-dimensional (2D) area detectors. The power of the method is illustrated here by applying it to a real measurement on a palladium-hydrogen sample.

Evaluating the SAMT English Textbook for BSc Students of Physics

Directory of Open Access Journals (Sweden)

Mina Sajjadi

2011-11-01

Full Text Available English for Academic Purposes (EAP and English for Specific Purposes (ESP are developing branches of English as a Foreign Language (EFL instruction in Iran. These branches have a marginal status in the tertiary education, and the Ministry of Science, Research, and Technology’s high commission offers no clear guidance for selecting and developing basic academic instructional materials related to the linguistic or communicative standards expected by teachers (Mazdayasna & Tahririan, 2008. This paper tries to evaluate an ESP textbook written for BSc students of physics entitled, ‘English for the students of physics’, which is prepared by the Center for Studying and Compiling University Books in Humanities (SAMT. The present research was based on qualitative and quantitative research techniques and included two steps. First, internal, external and overall evaluation of the book was carried out based on McDonough & Shaw (1993 model. While conducting the external evaluation of the book, the intended audience, the proficiency level, the context of use, the language, the author's views on language and methodology, the inclusion of a vocabulary list/index, visual features, and the cultural aspects were examined. The internal evaluation included the presentation of the skills, grading and sequencing, discourse skills, listening section, the representation of different learning styles. And in overall evaluation, general suitability of the textbook was assessed. In the second step, six teachers each responded to a 22-item textbook evaluation questionnaire to express their perceptions concerning various aspects of the textbooks. The results revealed the extent of appropriateness of the textbook used by BSc students of physics. Suggestions are offered for the future revision and/or designing the textbooks.

Learning English with Electronic Textbooks on Tablet PCs

Science.gov (United States)

Lin, Chih-cheng

2017-01-01

Previous studies on electronic textbooks were all survey studies of college students in the U.S.A. Their main findings revealed that using electronic textbooks and using print textbooks showed no statistical differences in learning achievements. As mobile devices became popular in classrooms, the present study was intended to confirm the…

Manufacturing Visions of Society and History in Textbooks.

Science.gov (United States)

Perlmutter, David D.

1997-01-01

Finds that the secondary-school textbook vision of society is homogenized and sanitized to reduce the risk of controversy. Reveals three domains of control that influence textbook visual content: industrial (how the image world of a textbook is created); commercial (marketing pressures); and social (interest groups that influence the visual…

Finally, nuclear engineering textbooks with a Canadian flavour!

International Nuclear Information System (INIS)

Bonin, H.W.

2002-01-01

The need for nuclear engineering textbooks more appropriate to the Canadian nuclear industry context and the CANDU nuclear reactor program has long been felt not only among the universities offering nuclear engineering programs at the graduate level, but also within the Canadian nuclear industry itself. Coverage of the CANDU reactor system in the textbooks presently supporting teaching is limited to a brief description of the concept. Course instructors usually complement these textbooks with course notes written from their personal experience from past employment within the nuclear industry and from their research interests In the last ten years, the Canadian nuclear industry has been involved on an increasing basis with the issue of the technology transfer to foreign countries which have purchased CANDU reactors or have been in the process of purchasing one or several CANDUs. For some of these countries, the 'turn key' approach is required, in which the Canadian nuclear industry looks after everything up to the commissioning of the nuclear power plant, including the education and training of local nuclear engineers and plant personnel. Atomic Energy of Canada Limited (AECL) in particular has dispatched some personnel tasked to prepare and give short courses on some specific aspects of CANDU design and operation, but a lack of consistency was observed as different persons prepared and gave the courses rather independently. To address the many problems tied with nuclear engineering education, the CANTEACH program was set up involving major partners of the Canadian nuclear industry. Parts of the activities foreseen by CANTEACH consist in the writing of nuclear engineering textbooks and associated computer-based pedagogical material. The present paper discusses the main parts of two textbooks being produced, one in reactor physics at steady state and the other on nuclear fuel management. (author)

Velocity and Dispersion for a Two-Dimensional Random Walk

International Nuclear Information System (INIS)

Li Jinghui

2009-01-01

In the paper, we consider the transport of a two-dimensional random walk. The velocity and the dispersion of this two-dimensional random walk are derived. It mainly show that: (i) by controlling the values of the transition rates, the direction of the random walk can be reversed; (ii) for some suitably selected transition rates, our two-dimensional random walk can be efficient in comparison with the one-dimensional random walk. Our work is motivated in part by the challenge to explain the unidirectional transport of motor proteins. When the motor proteins move at the turn points of their tracks (i.e., the cytoskeleton filaments and the DNA molecular tubes), some of our results in this paper can be used to deal with the problem. (general)

Theory of the one- and two-dimensional electron gas

International Nuclear Information System (INIS)

Emery, V.J.

1987-01-01

Two topics are discussed: (1) the competition between 2k/sub F/ and 4k/sub F/ charge state waves in a one-dimensional electron gas and (2) a two-dimensional model of high T/sub c/ superconductivity in the oxides

The Spanish Language textbook in Chile and Cuba

Directory of Open Access Journals (Sweden)

Jorge Marcelo Ayzum Echeverría

2015-09-01

Full Text Available The paper presents a description and analysis of the content of textbook of Language and Communication (Spanish in Cuba considering the indispensable tasks for fostering a developmental learning. A comparative analysis of fourth year Cuban and Chilean textbook contents was carried following certain criteria that normally promote good learning practices. Once the textbooks were compared, the findings suggest that school textbooks should be selected on the basis of the criteria taken as reference, in the meantime, such criteria may lead teacher to design complementary tasks.

Navigating the Minefield of Self-Publishing E-Textbooks

Science.gov (United States)

Schultz, Leah

2017-01-01

This paper examines the issues useful for faculty members that are considering electronically self-publishing their course textbook. A brief history of the use of electronic textbooks is presented as well as the advantages and disadvantages associated with self-publishing and electronic textbooks. A brief overview is provided on the process of…

Coordinating Multiple Representations in a Reform Calculus Textbook

Science.gov (United States)

Chang, Briana L.; Cromley, Jennifer G.; Tran, Nhi

2016-01-01

Coordination of multiple representations (CMR) is widely recognized as a critical skill in mathematics and is frequently demanded in reform calculus textbooks. However, little is known about the prevalence of coordination tasks in such textbooks. We coded 707 instances of CMR in a widely used reform calculus textbook and analyzed the distributions…

The inaccuracy of conventional one-dimensional parallel thermal resistance circuit model for two-dimensional composite walls

International Nuclear Information System (INIS)

Wong, K.-L.; Hsien, T.-L.; Hsiao, M.-C.; Chen, W.-L.; Lin, K.-C.

2008-01-01

This investigation is to show that two-dimensional steady state heat transfer problems of composite walls should not be solved by the conventionally one-dimensional parallel thermal resistance circuits (PTRC) model because the interface temperatures are not unique. Thus PTRC model cannot be used like its conventional recognized analogy, parallel electrical resistance circuits (PERC) model which has the unique node electric voltage. Two typical composite wall examples, solved by CFD software, are used to demonstrate the incorrectness. The numerical results are compared with those obtained by PTRC model, and very large differences are observed between their results. This proves that the application of conventional heat transfer PTRC model to two-dimensional composite walls, introduced in most heat transfer text book, is totally incorrect. An alternative one-dimensional separately series thermal resistance circuit (SSTRC) model is proposed and applied to the two-dimensional composite walls with isothermal boundaries. Results with acceptable accuracy can be obtained by the new model

Usability of PDF based Digital Textbooks to the Physically Disabled University Student.

Science.gov (United States)

Oku, Hidehisa; Matsubara, Kayoko; Booka, Masayuki

2015-01-01

Digital textbooks have been expected for providing multimedia information that the print textbooks could not handle. The original digital textbook can be fabricated relatively easily by using Epub or DAISY. Print textbooks are, however, employed as textbooks in the most of lectures in universities. Therefore, it is considered necessary to convert the content of the print textbook to the digital textbook simply and in a short time. In this paper, the digital textbook using PDF files of the print textbook was suggested as one of simple and practical solution to provide an alternative textbook for the physically disabled university student who has difficulty handling the print textbook. Then usability of the suggested method was evaluated experimentally from the point of workload. Result of the experiment indicates that the digital textbook fabricated as the alternative one for the print textbook by the suggested method has a potential to reduce workload for the physically disabled university students. In addition, the digital textbook with larger LCD display needs less workload than the print textbook. Then, there are not so much difference in the workload between the print book which is smaller than the print textbook and the digital book made from the print book.

Numerical Simulations of Scattering of Light from Two-Dimensional Rough Surfaces Using the Reduced Rayleigh Equation

Directory of Open Access Journals (Sweden)

Tor eNordam

2013-09-01

Full Text Available A formalism is introduced for the non-perturbative, purely numerical, solution of the reduced Rayleigh equation for the scattering of light from two-dimensional penetrable rough surfaces. Implementation and performance issues of the method, and various consistency checks of it, are presented and discussed. The proposed method is found, within the validity of the Rayleigh hypothesis, to give reliable results. For a non-absorbing metal surface the conservation of energy was explicitly checked, and found to be satisfied to within 0.03%, or better, for the parameters assumed. This testifies to the accuracy of the approach and a satisfactory discretization. As an illustration, we calculate the full angular distribution of the mean differential reflection coefficient for the scattering of p- or s-polarized light incident on two-dimensional dielectric or metallic randomly rough surfaces defined by (isotropic or anisotropic Gaussian and cylindrical power spectra. Simulation results obtained by the proposed method agree well with experimentally measured scattering data taken from similar well-characterized, rough metal samples, or to results obtained by other numerical methods.

Two-dimensional fourier transform spectrometer

Science.gov (United States)

DeFlores, Lauren; Tokmakoff, Andrei

2013-09-03

The present invention relates to a system and methods for acquiring two-dimensional Fourier transform (2D FT) spectra. Overlap of a collinear pulse pair and probe induce a molecular response which is collected by spectral dispersion of the signal modulated probe beam. Simultaneous collection of the molecular response, pulse timing and characteristics permit real time phasing and rapid acquisition of spectra. Full spectra are acquired as a function of pulse pair timings and numerically transformed to achieve the full frequency-frequency spectrum. This method demonstrates the ability to acquire information on molecular dynamics, couplings and structure in a simple apparatus. Multi-dimensional methods can be used for diagnostic and analytical measurements in the biological, biomedical, and chemical fields.

Topological aspect of disclinations in two-dimensional crystals

International Nuclear Information System (INIS)

Wei-Kai, Qi; Tao, Zhu; Yong, Chen; Ji-Rong, Ren

2009-01-01

By using topological current theory, this paper studies the inner topological structure of disclinations during the melting of two-dimensional systems. From two-dimensional elasticity theory, it finds that there are topological currents for topological defects in homogeneous equation. The evolution of disclinations is studied, and the branch conditions for generating, annihilating, crossing, splitting and merging of disclinations are given. (the physics of elementary particles and fields)

Two-dimensional ranking of Wikipedia articles

Science.gov (United States)

Zhirov, A. O.; Zhirov, O. V.; Shepelyansky, D. L.

2010-10-01

The Library of Babel, described by Jorge Luis Borges, stores an enormous amount of information. The Library exists ab aeterno. Wikipedia, a free online encyclopaedia, becomes a modern analogue of such a Library. Information retrieval and ranking of Wikipedia articles become the challenge of modern society. While PageRank highlights very well known nodes with many ingoing links, CheiRank highlights very communicative nodes with many outgoing links. In this way the ranking becomes two-dimensional. Using CheiRank and PageRank we analyze the properties of two-dimensional ranking of all Wikipedia English articles and show that it gives their reliable classification with rich and nontrivial features. Detailed studies are done for countries, universities, personalities, physicists, chess players, Dow-Jones companies and other categories.

Teachers' Use of Textbooks in the Digital Age

Science.gov (United States)

Knight, Bruce Allen

2015-01-01

This paper explores teachers' use of textbooks in the digital age. After discussing student expectancies and needs, textbook use and the affordances of modern technology, the paper reports the results of a small-scale pilot study involving eight higher education teachers in Australia who discuss the use of textbooks in higher education in the…

Finding two-dimensional peaks

International Nuclear Information System (INIS)

Silagadze, Z.K.

2007-01-01

Two-dimensional generalization of the original peak finding algorithm suggested earlier is given. The ideology of the algorithm emerged from the well-known quantum mechanical tunneling property which enables small bodies to penetrate through narrow potential barriers. We merge this 'quantum' ideology with the philosophy of Particle Swarm Optimization to get the global optimization algorithm which can be called Quantum Swarm Optimization. The functionality of the newborn algorithm is tested on some benchmark optimization problems

Recognizing Perspectives: Narrative Differences and Hidden Ideologies in Taiwanese History Textbooks

Directory of Open Access Journals (Sweden)

Pei-Fen Sung

2015-12-01

Full Text Available Democratization allowed Taiwanese History to be established independently in the curriculum, and because Taiwanese consciousness and Chinese consciousness are two main historical ideologies in the history curriculum, there is a need for history teachers to have the ability to judge the underlying perspectives in Taiwanese History. This study utilizes three versions of Junior-high school Taiwanese history textbooks and examines three themes-- “The Origins of Taiwanese Aboriginals,” “The Historical Relationship between Taiwan and China,” and “the Mu-Dan-She Event” --to explain the narrative differences in the textbook accounts. We found Taiwanese consciousness, Chinese consciousness and international consciousness in the three different textbooks. However, these identity-related ideologies are embedded in historical facts that appear to be neutral making perspectives in the narratives unheeded. We believe that teachers need to help sensitize students with the underlying perspectives and interpretive frames in historical narratives in order to cultivate citizens’ rational thinking ability and to develop discernment in identifying identity education hidden in textbooks in a democratic society.

Digital simulation of two-dimensional random fields with arbitrary power spectra and non-Gaussian probability distribution functions.

Science.gov (United States)

Yura, Harold T; Hanson, Steen G

2012-04-01

Methods for simulation of two-dimensional signals with arbitrary power spectral densities and signal amplitude probability density functions are disclosed. The method relies on initially transforming a white noise sample set of random Gaussian distributed numbers into a corresponding set with the desired spectral distribution, after which this colored Gaussian probability distribution is transformed via an inverse transform into the desired probability distribution. In most cases the method provides satisfactory results and can thus be considered an engineering approach. Several illustrative examples with relevance for optics are given.

Quantum Communication Through a Two-Dimensional Spin Network

International Nuclear Information System (INIS)

Wang Zhaoming; Gu Yongjian

2012-01-01

We investigate the state or entanglement transfer through a two-dimensional spin network. We show that for state transfer, better fidelity can be gained along the diagonal direction but for entanglement transfer, when the initial entanglement is created along the boundary, the concurrence is more inclined to propagate along the boundary. This behavior is produced by quantum mechanical interference and the communication quality depends on the precise size of the network. For some number of sites, the fidelity in a two-dimensional channel is higher than one-dimensional case. This is an important result for realizing quantum communication through high dimension spin chain networks.

Two-dimensional wave propagation in layered periodic media

KAUST Repository

Quezada de Luna, Manuel

2014-09-16

We study two-dimensional wave propagation in materials whose properties vary periodically in one direction only. High order homogenization is carried out to derive a dispersive effective medium approximation. One-dimensional materials with constant impedance exhibit no effective dispersion. We show that a new kind of effective dispersion may arise in two dimensions, even in materials with constant impedance. This dispersion is a macroscopic effect of microscopic diffraction caused by spatial variation in the sound speed. We analyze this dispersive effect by using highorder homogenization to derive an anisotropic, dispersive effective medium. We generalize to two dimensions a homogenization approach that has been used previously for one-dimensional problems. Pseudospectral solutions of the effective medium equations agree to high accuracy with finite volume direct numerical simulations of the variable-coeffi cient equations.

Lorentz covariant tempered distributions in two-dimensional space-time

International Nuclear Information System (INIS)

Zinov'ev, Yu.M.

1989-01-01

The problem of describing Lorentz covariant distributions without any spectral condition has hitherto remained unsolved even for two-dimensional space-time. Attempts to solve this problem have already been made. Zharinov obtained an integral representation for the Laplace transform of Lorentz invariant distributions with support in the product of two-dimensional future light cones. However, this integral representation does not make it possible to obtain a complete description of the corresponding Lorentz invariant distributions. In this paper the author gives a complete description of Lorentz covariant distributions for two-dimensional space-time. No spectral conditions is assumed

Solution-Based Processing and Applications of Two-Dimensional Heterostructures

Science.gov (United States)

Hersam, Mark

Two-dimensional materials have emerged as promising candidates for next-generation electronics and optoelectronics, but advances in scalable nanomanufacturing are required to exploit this potential in real-world technology. This talk will explore methods for improving the uniformity of solution-processed two-dimensional materials with an eye toward realizing dispersions and inks that can be deposited into large-area thin-films. In particular, density gradient ultracentrifugation allows the solution-based isolation of graphene, boron nitride, montmorillonite, and transition metal dichalcogenides (e.g., MoS2, WS2, ReS2, MoSe2, WSe2) with homogeneous thickness down to the atomically thin limit. Similarly, two-dimensional black phosphorus is isolated in organic solvents or deoxygenated aqueous surfactant solutions with the resulting phosphorene nanosheets showing field-effect transistor mobilities and on/off ratios that are comparable to micromechanically exfoliated flakes. By adding cellulosic polymer stabilizers to these dispersions, the rheological properties can be tuned by orders of magnitude, thereby enabling two-dimensional material inks that are compatible with a range of additive manufacturing methods including inkjet, gravure, screen, and 3D printing. The resulting solution-processed two-dimensional heterostructures show promise in several device applications including photodiodes, anti-ambipolar transistors, gate-tunable memristors, and heterojunction photovoltaics.

Textbook difference

DEFF Research Database (Denmark)

Bennike, Rune Bolding

2015-01-01

space. However, it also highlights how this schooling concomitantly extended a language of ‘anthropological’ and ‘ecological’ difference with which to organise and negotiate this space. Below the textbook surface of unity-in-diversity, remnants of imperial caste and racial hierarchies remained. And...

MODEL WRITTEN TEXTS IN THE RECOMMENDED SENIOR HIGH SCHOOL ENGLISH TEXTBOOKS

Directory of Open Access Journals (Sweden)

Dwi Rukmini

2009-01-01

Full Text Available Abstract: This article is based on the study on the model written texts provided in the Senior High School English textbooks. It is aimed at finding out whether those models are written by considering the English two contexts, cultural and situational, which encircle them. The data are all written texts provided in the six recommended English textbooks published by six different publishers. The results reveal that only eleven out of 115 model written texts tend to be incompatible with the two contexts encircling them, this implies that 104 of them (93.43% are likely to be compatible and can be used as model texts.

Inter-layer Cooper pairing of two-dimensional electrons

International Nuclear Information System (INIS)

Inoue, Masahiro; Takemori, Tadashi; Yoshizaki, Ryozo; Sakudo, Tunetaro; Ohtaka, Kazuo

1987-01-01

The authors point out the possibility that the high transition temperatures of the recently discovered oxide superconductors are dominantly caused by the inter-layer Cooper pairing of two-dimensional electrons that are coupled through the exchange of three-dimensional phonons. (author)

Optimal Padding for the Two-Dimensional Fast Fourier Transform

Science.gov (United States)

Dean, Bruce H.; Aronstein, David L.; Smith, Jeffrey S.

2011-01-01

One-dimensional Fast Fourier Transform (FFT) operations work fastest on grids whose size is divisible by a power of two. Because of this, padding grids (that are not already sized to a power of two) so that their size is the next highest power of two can speed up operations. While this works well for one-dimensional grids, it does not work well for two-dimensional grids. For a two-dimensional grid, there are certain pad sizes that work better than others. Therefore, the need exists to generalize a strategy for determining optimal pad sizes. There are three steps in the FFT algorithm. The first is to perform a one-dimensional transform on each row in the grid. The second step is to transpose the resulting matrix. The third step is to perform a one-dimensional transform on each row in the resulting grid. Steps one and three both benefit from padding the row to the next highest power of two, but the second step needs a novel approach. An algorithm was developed that struck a balance between optimizing the grid pad size with prime factors that are small (which are optimal for one-dimensional operations), and with prime factors that are large (which are optimal for two-dimensional operations). This algorithm optimizes based on average run times, and is not fine-tuned for any specific application. It increases the amount of times that processor-requested data is found in the set-associative processor cache. Cache retrievals are 4-10 times faster than conventional memory retrievals. The tested implementation of the algorithm resulted in faster execution times on all platforms tested, but with varying sized grids. This is because various computer architectures process commands differently. The test grid was 512 512. Using a 540 540 grid on a Pentium V processor, the code ran 30 percent faster. On a PowerPC, a 256x256 grid worked best. A Core2Duo computer preferred either a 1040x1040 (15 percent faster) or a 1008x1008 (30 percent faster) grid. There are many industries that

Towards Development of OER Derived Custom-Built Open Textbooks: A Baseline Survey of University Teachers at the University of the South Pacific

Science.gov (United States)

Prasad, Deepak; Usagawa, Tsuyoshi

2014-01-01

Textbook prices have soared over the years, with several studies revealing many university students are finding it difficult to afford textbooks. Fortunately, two innovations--open educational resources (OER) and open textbooks--hold the potential to increase textbook affordability. Experts, though, have stated the obvious: that students can save…

Teaching three-dimensional surgical concepts of inguinal hernia in a time-effective manner using a two-dimensional paper-cut.

Science.gov (United States)

Mann, B D; Seidman, A; Haley, T; Sachdeva, A K

1997-06-01

Because inguinal hernia repair is difficult for third-year students to comprehend, a 2-dimensional paper-cut was developed to teach the concepts of inguinal hernia in a time-effective manner before students' observation of herniorrhaphy in the operating room. Using Adobe Illustrator 5.5 for MacIntosh, a 2-dimensional inexpensively printed paper-cut was created to allow students to perform their own simulated hernia repair before observing surgery. The exercise was performed using a no.15 scalpel or an iris scissors and was evaluated by comparing 10-question pre-tests and post-tests. Seventy-five students performed the exercise, most completing it within 15 minutes. The mean pre-test score was 7.4/10 and the mean post-test score was 9.1/10. Students performing the paper-cut reported better understanding when observing actual herniorrhaphy. A 2-dimensional paper-cut ("surgical origami") may be a time-effective method to prepare students for the observation of hernia repair.

Consumer Economics and Consumer Mathematics Textbooks.

Science.gov (United States)

Eastern Michigan Univ., Ypsilanti. National Inst. for Consumer Education.

This publication lists a selection of consumer economics and consumer mathematics textbooks available for review from the National Institute for Consumer Education. Twenty-six textbooks for the secondary level are cited. Nine advanced level texts are also listed. These texts are generally considered college level texts but could be adapted for…

Surface representations of two- and three-dimensional fluid flow topology

Science.gov (United States)

Helman, James L.; Hesselink, Lambertus

1990-01-01

We discuss our work using critical point analysis to generate representations of the vector field topology of numerical flow data sets. Critical points are located and characterized in a two-dimensional domain, which may be either a two-dimensional flow field or the tangential velocity field near a three-dimensional body. Tangent curves are then integrated out along the principal directions of certain classes of critical points. The points and curves are linked to form a skeleton representing the two-dimensional vector field topology. When generated from the tangential velocity field near a body in a three-dimensional flow, the skeleton includes the critical points and curves which provide a basis for analyzing the three-dimensional structure of the flow separation. The points along the separation curves in the skeleton are used to start tangent curve integrations to generate surfaces representing the topology of the associated flow separations.

Comparing Physics Textbooks in Terms of Assessment and Evaluation Tools

Directory of Open Access Journals (Sweden)

Zeynep Başkan Takaoğlu

2017-10-01

Full Text Available Assessment and evaluation instruments provide teachers the opportunity of shaping education in the beginning, contributing to education during the process and evaluating education at the end of the process. Textbooks, on the other hand, are resources that present the aforementioned contributions to teachers at first hand. Thus, the study aims to compare the distribution of assessment and evaluation instruments in the physics textbooks being used in the academic year of 2011- 2012 and 2016-2017 according to units, settlement within units and types of assessment instruments that are used. For that purpose, 9, 10, 11 and 12th grade textbooks being used in physics lessons in the academic year of 2011-2012 and 2016-2017 were examined via document analysis method. As a result of the study, it was determined that the highest number of assessment instruments in physics textbooks from two different years was encountered in the unit of force and motion. The reason for this unit having higher number of questions could be associated with higher number of mathematical operations in the unit intended for allowing students to overcome their mathematical deficiencies by practicing such questions. It was observed that the number of questions was increased especially in the books being used in the academic year of 2016-2017 and alternative assessment instruments were fewer than traditional assessment instruments. Traditional assessment instruments are still used very frequently in the textbooks, which proves the effect of traditional approaches in assessment and evaluation. Another reason for this condition is that a result-oriented evaluation is used in the university entrance exam. In the light of these results, it is suggested to make the university exam student-centered rather than making an arrangement in textbooks.

Quasi-integrability and two-dimensional QCD

International Nuclear Information System (INIS)

Abdalla, E.; Mohayaee, R.

1996-10-01

The notion of integrability in two-dimensional QCD is discussed. We show that in spite of an infinite number of conserved charges, particle production is not entirely suppressed. This phenomenon, which we call quasi-integrability, is explained in terms of quantum corrections to the combined algebra of higher-conserved and spectrum-generating currents. We predict the qualitative form of particle production probabilities and verify that they are in agreement with numerical data. We also discuss four-dimensional self-dual Yang-Mills theory in the light of our results. (author). 25 refs, 4 figs, 1 tab

Two-dimensional QCD in the Coulomb gauge

International Nuclear Information System (INIS)

Kalashnikova, Yu.S.; Nefed'ev, A.V.

2002-01-01

Various aspects of the 't Hooft model for two-dimensional QCD in the limit of infinite number of colours in the Coulomb gauge are discussed. The properties of mesonic excitations are studied, with special emphasis on the pion. Attention is paid to the dual role of the pion. which, while a genuine qq-bar state, is a Goldstone boson of two-dimensional QCD as well. In particular, the validity of the soft-pion theorems is demonstrated. It is shown that the Coulomb gauge is the most suitable choice for the study of hadronic observables involving pions [ru

The Introductory Psychology Textbook Market: Perceptions of Authors and Editors.

Science.gov (United States)

Griggs, Richard A.; Jackson, Sherri L.

1989-01-01

Surveys psychology textbook authors and editors on their perceptions of the introductory psychology textbook market. Finds that the textbook market is divided into three levels according to quality, and that authors and editors are not familiar with most textbooks. Notes that the growth of used book companies has adversely affected the market.…

Who's Who in Introductory Psychology Textbooks: A Citation Analysis Redux

Science.gov (United States)

Griggs, Richard A.; Christopher, Andrew N.

2016-01-01

It is important to assess periodically how introductory textbooks portray our discipline because introductory psychology is the most popular psychology course, almost all teachers use textbooks for it, and textbooks play a major role in defining the course for students. To do so, past studies have used textbook citation analyses. We analyzed…

Representation of Hidden Curriculum in EFL Textbook (Gender Markers

Directory of Open Access Journals (Sweden)

Ekaterina E. Shishlova

2014-01-01

Full Text Available The article considers the mechanism ofrepresenting the hidden curriculum in the discourse of EFL textbooks, i.e. the transmission ofsociocultural norms and values of native speakers to foreign students. To do this the authors make a brieftheoretical review of this problem and demonstrate the results of the comparative discourse analysis of two popular textbooks, the one of the pre-globalization age and the present-day one. The authors provide evidence for their idea of the dual role, which English plays today being simultaneously a national language of different English-speaking societies and the global lingua franca. The conducted discourse analysis is based on the analysis of semiotic means, which are used to nominate concepts basic to any society and culture. In the article, the authors demonstrate their own plan of analysis by the example of the "gender" concept. The gender concept shows social and cultural conditionality of distinctions in behavior and the identity of men and women. The comparative analysis of gender markers in the discourse of EFL textbooks reveals a global vector of transformation and distribution ofsociocultural values. Authors state that cultural expansion through English teaching is an instrument of smart power. It is suggested using the mechanism of transmission ofsociocultural norms and values, which is analyzed in the research, to create Russian textbooks for foreign students.

Sensitivity analysis explains quasi-one-dimensional current transport in two-dimensional materials

DEFF Research Database (Denmark)

Boll, Mads; Lotz, Mikkel Rønne; Hansen, Ole

2014-01-01

We demonstrate that the quasi-one-dimensional (1D) current transport, experimentally observed in graphene as measured by a collinear four-point probe in two electrode configurations A and B, can be interpreted using the sensitivity functions of the two electrode configurations (configurations...... A and B represents different pairs of electrodes chosen for current sources and potential measurements). The measured sheet resistance in a four-point probe measurement is averaged over an area determined by the sensitivity function. For a two-dimensional conductor, the sensitivity functions for electrode...... configurations A and B are different. But when the current is forced to flow through a percolation network, e.g., graphene with high density of extended defects, the two sensitivity functions become identical. This is equivalent to a four-point measurement on a line resistor, hence quasi-1D transport...

Noise-induced drift in two-dimensional anisotropic systems

Science.gov (United States)

Farago, Oded

2017-10-01

We study the isothermal Brownian dynamics of a particle in a system with spatially varying diffusivity. Due to the heterogeneity of the system, the particle's mean displacement does not vanish even if it does not experience any physical force. This phenomenon has been termed "noise-induced drift," and has been extensively studied for one-dimensional systems. Here, we examine the noise-induced drift in a two-dimensional anisotropic system, characterized by a symmetric diffusion tensor with unequal diagonal elements. A general expression for the mean displacement vector is derived and presented as a sum of two vectors, depicting two distinct drifting effects. The first vector describes the tendency of the particle to drift toward the high diffusivity side in each orthogonal principal diffusion direction. This is a generalization of the well-known expression for the noise-induced drift in one-dimensional systems. The second vector represents a novel drifting effect, not found in one-dimensional systems, originating from the spatial rotation in the directions of the principal axes. The validity of the derived expressions is verified by using Langevin dynamics simulations. As a specific example, we consider the relative diffusion of two transmembrane proteins, and demonstrate that the average distance between them increases at a surprisingly fast rate of several tens of micrometers per second.

Three-dimensional echocardiography of normal and pathologic mitral valve: a comparison with two-dimensional transesophageal echocardiography

NARCIS (Netherlands)

Salustri, A.; Becker, A. E.; van Herwerden, L.; Vletter, W. B.; ten Cate, F. J.; Roelandt, J. R.

1996-01-01

This study was done to ascertain whether three-dimensional echocardiography can facilitate the diagnosis of mitral valve abnormalities. The value of the additional information provided by three-dimensional echocardiography compared with two-dimensional multiplane transesophageal echocardiography for

Gender Scripts in Professional Writing Textbooks.

Science.gov (United States)

Carrell, David

1991-01-01

Examines sexual stereotypes in selected professional writing textbooks published from the 1930s to the 1950s. Maintains that these textbooks--portraying women as subservient, emotional, and frivolous, and men as decisive, logical, and strong--suggest that men are more suited for positions of authority, and have played an important role in…

Open-Access Electronic Textbooks: An Overview

Science.gov (United States)

Ovadia, Steven

2011-01-01

Given the challenging economic climate in the United States, many academics are looking to open-access electronic textbooks as a way to provide students with traditional textbook content at a more financially advantageous price. Open access refers to "the free and widely available information throughout the World Wide Web. Once an article's…

Two-Dimensional Motions of Rockets

Science.gov (United States)

Kang, Yoonhwan; Bae, Saebyok

2007-01-01

We analyse the two-dimensional motions of the rockets for various types of rocket thrusts, the air friction and the gravitation by using a suitable representation of the rocket equation and the numerical calculation. The slope shapes of the rocket trajectories are discussed for the three types of rocket engines. Unlike the projectile motions, the…

A Thorough Scrutiny of ELT Textbook Evaluations: A Review Inquiry

Directory of Open Access Journals (Sweden)

Reza Gholami

2017-07-01

Full Text Available It is thoroughly agreed that English language textbooks stand amongst the foremost components in any language classrooms worldwide, being referred to as valid, beneficial and labor-saving tools to fulfill an extensive range of needs. An ELT textbook is not merely a set of sheets of paper fastened together to hinge at one side, but is the beating heart of any education system whereupon the whole learning revolves. Notwithstanding their interminable benefits, it is admitted that still the compiled textbooks, especially the ones prescribed in Educational systems have to be evaluated and assessed to confirm whether they fulfil the objectives they are meant for or not, as it is said no perfect textbook exists. Having dealt with evaluation in general, this research meticulously elaborates on textbook evaluation more specifically concluding that there is a dearth of inquiry on textbook selection and evaluation. Afterwards, this research introduces the most common approaches for evaluating ELT textbooks and materials. The paper culminates with concluding remarks and implications, hoping to shed light on how textbook evaluation is practiced worldwide.

Two-Dimensional Theory of Scientific Representation

Directory of Open Access Journals (Sweden)

A Yaghmaie

2013-03-01

Full Text Available Scientific representation is an interesting topic for philosophers of science, many of whom have recently explored it from different points of view. There are currently two competing approaches to the issue: cognitive and non-cognitive, and each of them claims its own merits over the other. This article tries to provide a hybrid theory of scientific representation, called Two-Dimensional Theory of Scientific Representation, which has the merits of the two accounts and is free of their shortcomings. To do this, we will argue that although scientific representation needs to use the notion of intentionality, such a notion is defined and realized in a simply structural form contrary to what cognitive approach says about intentionality. After a short introduction, the second part of the paper is devoted to introducing theories of scientific representation briefly. In the third part, the structural accounts of representation will be criticized. The next step is to introduce the two-dimensional theory which involves two key components: fixing and structural fitness. It will be argued that fitness is an objective and non-intentional relation, while fixing is intentional.

Sex division of labour in Syrian school textbooks

Science.gov (United States)

Alrabaa, Sami

1985-12-01

The sexist division of labour, particularly in the occupational sector, which is believed to be more eminent in developing countries than in the developed ones, is reinforced by school textbooks. This state of affairs is hampering sex-role equality on the way to emancipation. Various Syrian school textbooks have been scrutinized and proved to be malebiased in content and language. Despite quantitative growth of education, the emancipatory quality of the school textbooks leaves much to be desired. The government has had the chance since 1963 to produce textbooks conductive to its promise of sex-role equality in education. The textbooks portray males for a bustling world of decision making, while conditioning the females to seek fulfilment in the background where servitude and support are the only requirement. Females are derogated and victimized. These contents, which are internalized at school and reproduced in society, certainly do not serve development. The exclusion of one-half of the population from contributing to the tasks of development is a waste of human talent which no society can afford. Furthermore, the sexist portrayal of females in Syrian textbooks is a pale reflection of Arab women in Arab history and literature.

Scientific explanations in Greek upper secondary physics textbooks

Science.gov (United States)

Velentzas, Athanasios; Halkia, Krystallia

2018-01-01

In this study, an analysis of the structure of scientific explanations included in physics textbooks of upper secondary schools in Greece was completed. In scientific explanations for specific phenomena found in the sample textbooks, the explanandum is a logical consequence of the explanans, which in all cases include at least one scientific law (and/or principle, model or rule) previously presented, as well as statements concerning a specific case or specific conditions. The same structure is also followed in most of the cases in which the textbook authors explain regularities (i.e. laws, rules) as consequences of one or more general law or principle of physics. Finally, a number of the physics laws and principles presented in textbooks are not deduced as consequences from other, more general laws, but they are formulated axiomatically or inductively derived and the authors argue for their validity. Since, as it was found, the scientific explanations presented in the textbooks used in the study have similar structures to the explanations in internationally known textbooks, the findings of the present work may be of interest not only to science educators in Greece, but also to the community of science educators in other countries.

Motivating students to read the textbook before class

Science.gov (United States)

Pepper, Rachel E.

2016-11-01

Many faculty in STEM courses assign textbook reading in advance of lecture, yet evidence shows few students actually read the textbook. Those students that do read often do so only after the material has been presented in class. Preparing for class by reading the textbook beforehand improves student learning and is particularly critical for classes that employ active engagement strategies. Here I present strategies I have used to successfully motivate my students to read the textbook before class in physics classes ranging from introductory algebra-based physics to advanced courses for physics majors. In the introductory course, I used pre-class reading quizzes, a common strategy that has been shown effective in previous studies, but one that is somewhat time-consuming to implement. In my more advanced courses I used reading reflections, which required considerably less time. While it was typical for less than 25% of students to read the textbook before I implemented reading quizzes or reflections, after implementing these strategies 70-90% of students reported reading the textbook before class most of the time. Students also report finding both the readings themselves and the quizzes and reflections valuable for their learning.

Student Perceptions of Textbook Layout and Learnability in Private Schools

Directory of Open Access Journals (Sweden)

Alefiyah Hoshangabadwala

2015-06-01

Full Text Available This research is an exploratory study that investigates students’ perceptions pertinent to textbook layout and organization and their evaluation of the textbook ease of learning. The objective is to find out whether the layout dynamics of school textbooks make any difference in students’ interest in studying or subject understanding. 73 students from various private schools of Pakistan’s cosmopolitan city Karachi responded to a quantitative survey that gauged their perceptions regarding textbook components such as paper, print, color, and textbook pedagogical features. Findings indicate that students rank print and color above paper quality, and that there is no particular relationship between a book layout and the actual use of textbooks.

Textbooks on the Move: Transforming a Textbook Collection

Science.gov (United States)

Ferguson, Yoko Inagi; Riley-Reid, Trevar

2017-01-01

Recently, The City College of New York (CCNY) libraries engaged in a collaborative project to transfer the bibliographic holdings for textbook course reserves to a new module when their integrated library systems, the Ex Libris Aleph Integrated Library System, underwent a system upgrade. In this article, the Chief of Circulation and the Chief of…

Two-dimensional Simulations of Correlation Reflectometry in Fusion Plasmas

International Nuclear Information System (INIS)

Valeo, E.J.; Kramer, G.J.; Nazikian, R.

2001-01-01

A two-dimensional wave propagation code, developed specifically to simulate correlation reflectometry in large-scale fusion plasmas is described. The code makes use of separate computational methods in the vacuum, underdense and reflection regions of the plasma in order to obtain the high computational efficiency necessary for correlation analysis. Simulations of Tokamak Fusion Test Reactor (TFTR) plasma with internal transport barriers are presented and compared with one-dimensional full-wave simulations. It is shown that the two-dimensional simulations are remarkably similar to the results of the one-dimensional full-wave analysis for a wide range of turbulent correlation lengths. Implications for the interpretation of correlation reflectometer measurements in fusion plasma are discussed

Volume scanning three-dimensional display with an inclined two-dimensional display and a mirror scanner

Science.gov (United States)

Miyazaki, Daisuke; Kawanishi, Tsuyoshi; Nishimura, Yasuhiro; Matsushita, Kenji

2001-11-01

A new three-dimensional display system based on a volume-scanning method is demonstrated. To form a three-dimensional real image, an inclined two-dimensional image is rapidly moved with a mirror scanner while the cross-section patterns of a three-dimensional object are displayed sequentially. A vector-scan CRT display unit is used to obtain a high-resolution image. An optical scanning system is constructed with concave mirrors and a galvanometer mirror. It is confirmed that three-dimensional images, formed by the experimental system, satisfy all the criteria for human stereoscopic vision.

Waste management - textbook for secondary schools

International Nuclear Information System (INIS)

Chmielewska, E.; Kuruc, J.

2010-09-01

This text-book consist of five parts: (I) Waste management; (II) Solid waste management; (III) Recovery and recycling of secondary raw materials; (IV) Radioactive waste management; Examples of verification knowledge and testing of the secondary students through the worksheet. (V) Suggestions for leisure time activities. This text-book is assigned for high school students.

Three-dimensional tokamak equilibria and stellarators with two-dimensional magnetic symmetry

International Nuclear Information System (INIS)

Garabedian, P.R.

1997-01-01

Three-dimensional computer codes have been developed to simulate equilibrium, stability and transport in tokamaks and stellarators. Bifurcated solutions of the tokamak problem suggest that three-dimensional effects may be more important than has generally been thought. Extensive calculations have led to the discovery of a stellarator configuration with just two field periods and with aspect ratio 3.2 that has a magnetic field spectrum B mn with toroidal symmetry. Numerical studies of equilibrium, stability and transport for this new device, called the Modular Helias-like Heliac 2 (MHH2), will be presented. (author)

A two-stage preventive maintenance optimization model incorporating two-dimensional extended warranty

International Nuclear Information System (INIS)

Su, Chun; Wang, Xiaolin

2016-01-01

In practice, customers can decide whether to buy an extended warranty or not, at the time of item sale or at the end of the basic warranty. In this paper, by taking into account the moments of customers purchasing two-dimensional extended warranty, the optimization of imperfect preventive maintenance for repairable items is investigated from the manufacturer's perspective. A two-dimensional preventive maintenance strategy is proposed, under which the item is preventively maintained according to a specified age interval or usage interval, whichever occurs first. It is highlighted that when the extended warranty is purchased upon the expiration of the basic warranty, the manufacturer faces a two-stage preventive maintenance optimization problem. Moreover, in the second stage, the possibility of reducing the servicing cost over the extended warranty period is explored by classifying customers on the basis of their usage rates and then providing them with customized preventive maintenance programs. Numerical examples show that offering customized preventive maintenance programs can reduce the manufacturer's warranty cost, while a larger saving in warranty cost comes from encouraging customers to buy the extended warranty at the time of item sale. - Highlights: • A two-dimensional PM strategy is investigated. • Imperfect PM strategy is optimized by considering both two-dimensional BW and EW. • Customers are categorized based on their usage rates throughout the BW period. • Servicing cost of the EW is reduced by offering customized PM programs. • Customers buying the EW at the time of sale is preferred for the manufacturer.

Gender bias in Islamic textbooks for Muslim children in Indonesia

Directory of Open Access Journals (Sweden)

Suwardi Suwardi

2018-01-01

Full Text Available Textbook has a strong influence on the formation of children’s attitudes and value system. Therefore, Islamic textbooks as the main learning source for Muslim children in Indonesia need to consider the gender equality. This is very important to note, because feminists often view that Islam contains teachings of gender inequality. Islam places men in the higher position, while women are placed in the lower position. For example, men can be imam for women in prayer, but women cannot be imam for men. It is easier for children to learn textbook material presented in pictures. Therefore, the pictures presented in Islamic textbooks ideally do not contain gender bias. So, a research is needed to know if there is gender bias in the pictures presented in Islamic textbooks taught to Muslim children in Indonesia. To prove it, a literary research is conducted on the Islamic textbooks taught to the first grade Muslim student of Islamic Elementary School/ Madrasah Ibtidaiyah (MI in Indonesia which includes pictures in their teaching materials. Islamic textbooks studied in the research include Fikih, Akidah Akhlak, and Arabic textbooks. The results of this study conclude that the pictures presented in Islamic textbooks taught in Muslim children in Indonesia contain gender bias. The man favor pictures are more than those of woman favor. Based on the conclusion, this study recommends an improvement of pictures presented in Islamic textbooks taught to Muslim children in Indonesia.

How do Five American Political Science Textbooks Deal with the Economic Dimension?

DEFF Research Database (Denmark)

Madsen, Poul Thøis

2011-01-01

Politics and economics interact. As a consequence, political science textbooks must often relate to the economic dimension—implicitly or explicitly. But we know very little about how these textbooks relate to economics. Are they merely unreflective customers of neoclassical economics or do...... they strive for a cross-disciplinary approach? An analysis of five American textbooks identifies two very different and concurrent interactions between politics and economics. The first is a theoretically conceived market economy in which market forces independently drive growth and create equilibrium, where...... politics has a rather secluded role. The second is the actually existing mixed economy, characterized by increased inequality, economic concentration, power, and environmental problems, influenced by a state forced to regulate. The problems of operating with such a dichotomy— and possible solutions...

Vibrations of thin piezoelectric shallow shells: Two-dimensional ...

Indian Academy of Sciences (India)

R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

In this paper we consider the eigenvalue problem for piezoelectric shallow shells and we show that, as the thickness of the shell goes to zero, the eigensolutions of the three-dimensional piezoelectric shells converge to the eigensolutions of a two- dimensional eigenvalue problem. Keywords. Vibrations; piezoelectricity ...

Two-dimensional turbulent flows on a bounded domain

NARCIS (Netherlands)

Kramer, W.

2006-01-01

Large-scale flows in the oceans and the atmosphere reveal strong similarities with purely two-dimensional flows. One of the most typical features is the cascade of energy from smaller flow scales towards larger scales. This is opposed to three-dimensional turbulence where larger flow structures

Intrinsic two-dimensional states on the pristine surface of tellurium

Science.gov (United States)

Li, Pengke; Appelbaum, Ian

2018-05-01

Atomic chains configured in a helical geometry have fascinating properties, including phases hosting localized bound states in their electronic structure. We show how the zero-dimensional state—bound to the edge of a single one-dimensional helical chain of tellurium atoms—evolves into two-dimensional bands on the c -axis surface of the three-dimensional trigonal bulk. We give an effective Hamiltonian description of its dispersion in k space by exploiting confinement to a virtual bilayer, and elaborate on the diminished role of spin-orbit coupling. These intrinsic gap-penetrating surface bands were neglected in the interpretation of seminal experiments, where two-dimensional transport was otherwise attributed to extrinsic accumulation layers.

A two dimensional approach for temperature distribution in reactor lower head during severe accident

International Nuclear Information System (INIS)

Cao, Zhen; Liu, Xiaojing; Cheng, Xu

2015-01-01

Highlights: • Two dimensional module is developed to analyze integrity of lower head. • Verification step has been done to evaluate feasibility of new module. • The new module is applied to simulate large-scale advanced PWR. • Importance of 2-D approach is clearly quantified. • Major parameters affecting vessel temperature distribution are identified. - Abstract: In order to evaluate the safety margin during a postulated severe accident, a module named ASAP-2D (Accident Simulation on Pressure vessel-2 Dimensional), which can be implemented into the severe accident simulation codes (such as ATHLET-CD), is developed in Shanghai Jiao Tong University. Based on two-dimensional spherical coordinates, heat conduction equation for transient state is solved implicitly. Together with solid vessel thickness, heat flux distribution and heat transfer coefficient at outer vessel surface are obtained. Heat transfer regime when critical heat flux has been exceeded (POST-CHF regime) could be simulated in the code, and the transition behavior of boiling crisis (from spatial and temporal points of view) can be predicted. The module is verified against a one-dimensional analytical solution with uniform heat flux distribution, and afterwards this module is applied to the benchmark illustrated in NUREG/CR-6849. Benchmark calculation indicates that maximum heat flux at outer surface of RPV could be around 20% lower than that of at inner surface due to two-dimensional heat conduction. Then a preliminary analysis is performed on the integrity of the reactor vessel for which the geometric parameters and boundary conditions are derived from a large scale advanced pressurized water reactor. Results indicate that heat flux remains lower than critical heat flux. Sensitivity analysis indicates that outer heat flux distribution is more sensitive to input heat flux distribution and the transition boiling correlation than mass flow rate in external reactor vessel cooling (ERVC) channel

Les illustrations interactives dans le manuel scolaire numérique en France : usages et impacts sur l'appropriation

OpenAIRE

Nikitopoulos , Claire

2017-01-01

The textbook evolves with the development of digital technology and proposes new resources. The illustrations are no longer static as in printed manuals, but based on interactivity. These animations, diagrams and interactive maps have a positive influence on students' memorization and understanding. Many researchers specializing in multimedia learning have highlighted these positive effects. According to J. Sweller, learning is favored when learning materials reduce the cognitive burden. J. S...

Iterative Two- and One-Dimensional Methods for Three-Dimensional Neutron Diffusion Calculations

International Nuclear Information System (INIS)

Lee, Hyun Chul; Lee, Deokjung; Downar, Thomas J.

2005-01-01

Two methods are proposed for solving the three-dimensional neutron diffusion equation by iterating between solutions of the two-dimensional (2-D) radial and one-dimensional (1-D) axial solutions. In the first method, the 2-D/1-D equations are coupled using a current correction factor (CCF) with the average fluxes of the lower and upper planes and the axial net currents at the plane interfaces. In the second method, an analytic expression for the axial net currents at the interface of the planes is used for planar coupling. A comparison of the new methods is made with two previously proposed methods, which use interface net currents and partial currents for planar coupling. A Fourier convergence analysis of the four methods was performed, and results indicate that the two new methods have at least three advantages over the previous methods. First, the new methods are unconditionally stable, whereas the net current method diverges for small axial mesh size. Second, the new methods provide better convergence performance than the other methods in the range of practical mesh sizes. Third, the spectral radii of the new methods asymptotically approach zero as the mesh size increases, while the spectral radius of the partial current method approaches a nonzero value as the mesh size increases. Of the two new methods proposed here, the analytic method provides a smaller spectral radius than the CCF method, but the CCF method has several advantages over the analytic method in practical applications

Construction of two-dimensional quantum chromodynamics

Energy Technology Data Exchange (ETDEWEB)

Klimek, S.; Kondracki, W.

1987-12-01

We present a sketch of the construction of the functional measure for the SU(2) quantum chromodynamics with one generation of fermions in two-dimensional space-time. The method is based on a detailed analysis of Wilson loops.

A two-dimensional Zn coordination polymer with a three-dimensional supra-molecular architecture.

Science.gov (United States)

Liu, Fuhong; Ding, Yan; Li, Qiuyu; Zhang, Liping

2017-10-01

The title compound, poly[bis-{μ 2 -4,4'-bis-[(1,2,4-triazol-1-yl)meth-yl]biphenyl-κ 2 N 4 : N 4' }bis-(nitrato-κ O )zinc(II)], [Zn(NO 3 ) 2 (C 18 H 16 N 6 ) 2 ] n , is a two-dimensional zinc coordination polymer constructed from 4,4'-bis-[(1 H -1,2,4-triazol-1-yl)meth-yl]-1,1'-biphenyl units. It was synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. The Zn II cation is located on an inversion centre and is coordinated by two O atoms from two symmetry-related nitrate groups and four N atoms from four symmetry-related 4,4'-bis-[(1 H -1,2,4-triazol-1-yl)meth-yl]-1,1'-biphenyl ligands, forming a distorted octa-hedral {ZnN 4 O 2 } coordination geometry. The linear 4,4'-bis-[(1 H -1,2,4-triazol-1-yl)meth-yl]-1,1'-biphenyl ligand links two Zn II cations, generating two-dimensional layers parallel to the crystallographic (132) plane. The parallel layers are connected by C-H⋯O, C-H⋯N, C-H⋯π and π-π stacking inter-actions, resulting in a three-dimensional supra-molecular architecture.

Two-dimensional effects in nonlinear Kronig-Penney models

DEFF Research Database (Denmark)

Gaididei, Yuri Borisovich; Christiansen, Peter Leth; Rasmussen, Kim

1997-01-01

An analysis of two-dimensional (2D) effects in the nonlinear Kronig-Penney model is presented. We establish an effective one-dimensional description of the 2D effects, resulting in a set of pseudodifferential equations. The stationary states of the 2D system and their stability is studied...

RHETORIC AND IDEOLOGY IN ECONOMICS TEXTBOOKS: AN OVERVIEW

OpenAIRE

ABA, Anıl

2018-01-01

This paper reviews the somewhat disconnected studies on the introductory level economics textbooks. First, specifying the best-sellers, it is argued that there is visible standardization and concentration in the textbook market. Second, studies focusing on the rhetorical and ideological aspects of economics textbooks are reviewed. While the heterodoxy, with determination, asserts that economics is inherently political and ideological, the mainstream, understandably, tends to deny the ideologi...

Textbook Forum: The Nernst Equation in High School Textbooks.

Science.gov (United States)

Perrine, Daniel M.

1984-01-01

Presents a problem on nonstandard concentrations at nonstandard temperature modeled after an example problem on the Nernst equation found in a high school chemistry textbook. Discusses why the problem is incorrect, offering a second problem which is correctly solved. Implications for teaching the Nernst equation are considered. (JN)

Noninteracting beams of ballistic two-dimensional electrons

International Nuclear Information System (INIS)

Spector, J.; Stormer, H.L.; Baldwin, K.W.; Pfeiffer, L.N.; West, K.W.

1991-01-01

We demonstrate that two beams of two-dimensional ballistic electrons in a GaAs-AlGaAs heterostructure can penetrate each other with negligible mutual interaction analogous to the penetration of two optical beams. This allows electrical signal channels to intersect in the same plane with negligible crosstalk between the channels

Control Operator for the Two-Dimensional Energized Wave Equation

Directory of Open Access Journals (Sweden)

Sunday Augustus REJU

2006-07-01

Full Text Available This paper studies the analytical model for the construction of the two-dimensional Energized wave equation. The control operator is given in term of space and time t independent variables. The integral quadratic objective cost functional is subject to the constraint of two-dimensional Energized diffusion, Heat and a source. The operator that shall be obtained extends the Conjugate Gradient method (ECGM as developed by Hestenes et al (1952, [1]. The new operator enables the computation of the penalty cost, optimal controls and state trajectories of the two-dimensional energized wave equation when apply to the Conjugate Gradient methods in (Waziri & Reju, LEJPT & LJS, Issues 9, 2006, [2-4] to appear in this series.

Equilibrium: two-dimensional configurations

International Nuclear Information System (INIS)

Anon.

1987-01-01

In Chapter 6, the problem of toroidal force balance is addressed in the simplest, nontrivial two-dimensional geometry, that of an axisymmetric torus. A derivation is presented of the Grad-Shafranov equation, the basic equation describing axisymmetric toroidal equilibrium. The solutions to equations provide a complete description of ideal MHD equilibria: radial pressure balance, toroidal force balance, equilibrium Beta limits, rotational transform, shear, magnetic wall, etc. A wide number of configurations are accurately modeled by the Grad-Shafranov equation. Among them are all types of tokamaks, the spheromak, the reversed field pinch, and toroidal multipoles. An important aspect of the analysis is the use of asymptotic expansions, with an inverse aspect ratio serving as the expansion parameter. In addition, an equation similar to the Grad-Shafranov equation, but for helically symmetric equilibria, is presented. This equation represents the leading-order description low-Beta and high-Beta stellarators, heliacs, and the Elmo bumpy torus. The solutions all correspond to infinitely long straight helices. Bending such a configuration into a torus requires a full three-dimensional calculation and is discussed in Chapter 7

A short textbook of colloid chemistry

CERN Document Server

Jirgensons, B

1962-01-01

A Short Textbook of Colloid Chemistry, Second Revised Edition details the factual aspect of colloid chemistry that includes the basic facts, established empirical and mathematical relationships, and practical applications. The chapters of the title are organized into two parts. In the first part, the text discusses the general concepts of colloid chemistry, such as the history and scope, basic terms, and basic methods in experiment with colloids. Part Two covers the technical aspect of colloid chemistry, such as the optical properties, electrical properties, and viscosity. The book will be of

Application of Fluorescence Two-Dimensional Difference In-Gel Electrophoresis as a Proteomic Biomarker Discovery Tool in Muscular Dystrophy Research

Science.gov (United States)

Carberry, Steven; Zweyer, Margit; Swandulla, Dieter; Ohlendieck, Kay

2013-01-01

In this article, we illustrate the application of difference in-gel electrophoresis for the proteomic analysis of dystrophic skeletal muscle. The mdx diaphragm was used as a tissue model of dystrophinopathy. Two-dimensional gel electrophoresis is a widely employed protein separation method in proteomic investigations. Although two-dimensional gels usually underestimate the cellular presence of very high molecular mass proteins, integral membrane proteins and low copy number proteins, this method is extremely powerful in the comprehensive analysis of contractile proteins, metabolic enzymes, structural proteins and molecular chaperones. This gives rise to two-dimensional gel electrophoretic separation as the method of choice for studying contractile tissues in health and disease. For comparative studies, fluorescence difference in-gel electrophoresis has been shown to provide an excellent biomarker discovery tool. Since aged diaphragm fibres from the mdx mouse model of Duchenne muscular dystrophy closely resemble the human pathology, we have carried out a mass spectrometry-based comparison of the naturally aged diaphragm versus the senescent dystrophic diaphragm. The proteomic comparison of wild type versus mdx diaphragm resulted in the identification of 84 altered protein species. Novel molecular insights into dystrophic changes suggest increased cellular stress, impaired calcium buffering, cytostructural alterations and disturbances of mitochondrial metabolism in dystrophin-deficient muscle tissue. PMID:24833232

Reasoning and Proving Opportunities in Textbooks: A Comparative Analysis

Science.gov (United States)

Hong, Dae S.; Choi, Kyong Mi

2018-01-01

In this study, we analyzed and compared reasoning and proving opportunities in geometry lessons from American standard-based textbooks and Korean textbooks to understand how these textbooks provide student opportunities to engage in reasoning and proving activities. Overall, around 40% of exercise problems in Core Plus Mathematics Project (CPMP)…

Islam in the Classroom: What The Textbooks Tell Us

Science.gov (United States)

Sewall, Gilbert T.

2008-01-01

This review samples ten of the nation's most widely used junior and senior high school history textbooks comparing what respected historians say about Islam in authoritative histories to what is being said in textbooks. It assesses how today's history textbooks characterize Islam's foundations and creeds; changes and additions that have occurred…

Extended Polymorphism of Two-Dimensional Material

NARCIS (Netherlands)

Yoshida, Masaro; Ye, Jianting; Zhang, Yijin; Imai, Yasuhiko; Kimura, Shigeru; Fujiwara, Akihiko; Nishizaki, Terukazu; Kobayashi, Norio; Nakano, Masaki; Iwasa, Yoshihiro

When controlling electronic properties of bulk materials, we usually assume that the basic crystal structure is fixed. However, in two-dimensional (2D) materials, atomic structure or to functionalize their properties. Various polymorphs can exist in transition metal dichalcogenides (TMDCs) from

Two-dimensional nonlinear equations of supersymmetric gauge theories

International Nuclear Information System (INIS)

Savel'ev, M.V.

1985-01-01

Supersymmetric generalization of two-dimensional nonlinear dynamical equations of gauge theories is presented. The nontrivial dynamics of a physical system in the supersymmetry and supergravity theories for (2+2)-dimensions is described by the integrable embeddings of Vsub(2/2) superspace into the flat enveloping superspace Rsub(N/M), supplied with the structure of a Lie superalgebra. An equation is derived which describes a supersymmetric generalization of the two-dimensional Toda lattice. It contains both super-Liouville and Sinh-Gordon equations

A Comparative Study of the Use of Collocation in Iranian High School Textbooks and American English File Books

Directory of Open Access Journals (Sweden)

Mohsen Shahrokhi

2014-05-01

Full Text Available The present study investigates the extent to which lexical and grammatical collocations are used in Iranian high school English textbooks, compared with the American English File books. To achieve the purposes of this study, this study had to be carried out in two phases. In the first phase, the content of the instructional textbooks, that is, American English File book series, Book 2 and Iranian high school English Book 3, were analyzed to find the frequencies and proportions of the collocations used in the textbooks. Since the instructional textbooks used in the two teaching environments (i.e., Iranian high schools and language institutes were not equal with regard to the density of texts, from each textbook just the first 6000 words, content words as well as function words, were considered. Then, the frequencies of the collocations among the first 6000 words in high school English Book 3 and American English File Book 2 were determined.The results of the statistical analyses revealed that the two text book series differ marginally in terms of frequency and type of collocations. Major difference existed between them when it came to lexical collocations in American English File book 2.

Surface acoustic waves in two dimensional phononic crystal with anisotropic inclusions

Directory of Open Access Journals (Sweden)

Ketata H.

2012-06-01

Full Text Available An analysis is given to the band structure of the two dimensional solid phononic crystal considered as a semi infinite medium. The lattice includes an array of elastic anisotropic materials with different shapes embedded in a uniform matrix. For illustration two kinds of phononic materials are assumed. A particular attention is devoted to the computational procedure which is mainly based on the plane wave expansion (PWE method. It has been adapted to Matlab environment. Numerical calculations of the dispersion curves have been achieved by introducing particular functions which transform motion equations into an Eigen value problem. Significant improvements are obtained by increasing reasonably the number of Fourier components even when a large elastic mismatch is assumed. Such approach can be generalized to different types of symmetry and permit new physical properties as piezoelectricity to be added. The actual semi infinite phononic structure with a free surface has been shown to support surface acoustic waves (SAW. The obtained dispersion curves reveal band gaps in the SAW branches. It has been found that the influence, of the filling factor and anisotropy on their band gaps, is different from that of bulk waves.

Evaluation of Malaysian English Language Teaching Textbooks

Directory of Open Access Journals (Sweden)

Jayakaran Mukundan

2013-07-01

Full Text Available Research in materials evaluation has been an important focus in ELT since the 1980s. The objective of the present study is to evaluate the general attributes of the textbooks and to evaluate the learning-teaching content. In this study, 944 male and female English teachers (Year 1 to Year 6 & Form 1 to Form 5 evaluated the English books using a valid and reliable checklist. In terms of general attributes and learning-teaching content of the textbooks, the results showed that Year 1 to Year 6 teachers reported that the current textbooks are ‘highly useful’ to the students, whereas Form 1 to Form 5 teachers contended that the school books are only ‘moderately useful’. The findings of this study can be useful for curricula designers and Ministry of Education as a reference for improving or modifying the textbooks.

Method of composing two-dimensional scanned spectra observed by the New Vacuum Solar Telescope

Science.gov (United States)

Cai, Yun-Fang; Xu, Zhi; Chen, Yu-Chao; Xu, Jun; Li, Zheng-Gang; Fu, Yu; Ji, Kai-Fan

2018-04-01

In this paper we illustrate the technique used by the New Vacuum Solar Telescope (NVST) to increase the spatial resolution of two-dimensional (2D) solar spectroscopy observations involving two dimensions of space and one of wavelength. Without an image stabilizer at the NVST, large scale wobble motion is present during the spatial scanning, whose instantaneous amplitude can reach 1.3″ due to the Earth’s atmosphere and the precision of the telescope guiding system, and seriously decreases the spatial resolution of 2D spatial maps composed with scanned spectra. We make the following effort to resolve this problem: the imaging system (e.g., the TiO-band) is used to record and detect the displacement vectors of solar image motion during the raster scan, in both the slit and scanning directions. The spectral data (e.g., the Hα line) which are originally obtained in time sequence are corrected and re-arranged in space according to those displacement vectors. Raster scans are carried out in several active regions with different seeing conditions (two rasters are illustrated in this paper). Given a certain spatial sampling and temporal resolution, the spatial resolution of the composed 2D map could be close to that of the slit-jaw image. The resulting quality after correction is quantitatively evaluated with two methods. A physical quantity, such as the line-of-sight velocities in multiple layers of the solar atmosphere, is also inferred from the re-arranged spectrum, demonstrating the advantage of this technique.

Links between Bloom's Taxonomy and Gardener's Multiple Intelligences: The issue of Textbook Analysis

Directory of Open Access Journals (Sweden)

Mahmoud Abdi Tabari

2015-02-01

Full Text Available The major thrust of this research was to investigate the cognitive aspect of the high school textbooks and interchange series, due to their extensive use, through content analysis based on Bloom's taxonomy and Gardner's Multiple Intelligences (MI. This study embraced two perspectives in a grid in order to broaden and deepen the analysis by determining the numbers and the types of intelligences with respect to their learning objectives tapped in the textbooks and comparing them. Through codification of Bloom’s learning objectives and Gardner's MI, the results showed that there was a significant difference between the numbers of intelligences with respect to their learning objectives in the textbooks. However, the interchange series enjoyed a large number of the spatial and the interpersonal intelligences across eight levels of learning objectives, whereas they had the least number of the intrapersonal, the musical, and the bodily-kinesthetic intelligences across knowledge understanding and application levels. Keywords: learning objectives, multiple intelligences, textbook analysis

Superintegrability on the two dimensional hyperboloid

International Nuclear Information System (INIS)

Akopyan, E.; Pogosyan, G.S.; Kalnins, E.G.; Miller, W. Jr

1998-01-01

This work is devoted to the investigation of the quantum mechanical systems on the two dimensional hyperboloid which admit separation of variables in at least two coordinate systems. Here we consider two potentials introduced in a paper of C.P.Boyer, E.G.Kalnins and P.Winternitz, which haven't been studied yet. An example of an interbasis expansion is given and the structure of the quadratic algebra generated by the integrals of motion is carried out

Few helium atoms in quasi two-dimensional space

International Nuclear Information System (INIS)

Kilic, Srecko; Vranjes, Leandra

2003-01-01

Two, three and four 3 He and 4 He atoms in quasi two-dimensional space above graphite and cesium surfaces and in 'harmonic' potential perpendicular to the surface have been studied. Using some previously examined variational wave functions and the Diffusion Monte Carlo procedure, it has been shown that all molecules: dimers, trimers and tetramers, are bound more strongly than in pure two- and three-dimensional space. The enhancement of binding with respect to unrestricted space is more pronounced on cesium than on graphite. Furthermore, for 3 He 3 ( 3 He 4 ) on all studied surfaces, there is an indication that the configuration of a dimer and a 'free' particle (two dimers) may be equivalently established

Top Textbooks on Reserve: Creating, Promoting, and Assessing a Program to Help Meet Students' Need for Affordable Textbooks

Science.gov (United States)

Thompson, Hilary H.; Cotton, Jennifer E. M.

2017-01-01

In Fall 2014 the University of Maryland Libraries launched a textbook reserves program to help relieve the burden of high textbook costs on students. Although its initial performance was lackluster, workflow refinements and expanded promotion greatly improved usage, resulting in a tenfold increase in circulation and expansion of the program. This…

Leishmaniasis and textbook: how are endemic diseases addressed in public education?

Directory of Open Access Journals (Sweden)

Débora Batista Reis

2014-03-01

Full Text Available Visceral Leishmaniasis is a vector-borne zoonosis, considered a public health problem in Brazil, because of their magnitude, geographic expansion and lethality. The disease is the etiologic agent trypanosamatid Leishmania infantum, is transmitted by the bite of Lutzomyia longipalpis, an insect of the order Diptera that has hematophagous habits. Typically considered rural, the disease emerged in the urban scene in Teresina, Piauí state, in the 80´s, reaching the other urban producing several epidemiological outbreaks. Control of the disease, based on the slaughter of seropositive dogs, chemical vector control and treatment of human patients as strategies recommended by the Ministry of Health, do not have satisfactory results, it is imperative to integrate these strategies to the actions of health education. Considering the role of the school in the dissemination of knowledge and the promotion of health education actions and, above all, the importance of the textbook as an important educational tool for the teaching-learning process, this study aimed to analyze the books as they are atopted by public schools of the city of Floriano, Piauí state, address endemic diseases, particularly leishmaniasis. Physical criteria, as aspects of the brochure and binding aspects and the contents were used in the analyzes. The selection of books was made by teachers and managers of schools based on the National Textbook Program (PNLD tab and then were approved in the pedagogical evaluation of the Ministry of Education. Copies of each level of education (primary and secondary were analyzed according to conceptual and physical aspects. The analysis of conceptual and methodological aspects was based on the literature and a thorough observation of the images that complement the content. The physical aspects were evaluated according to the type of binding, size, font size and spacing employ, didactic presentation order of the content and illustrations. It was found

Internal medicine. An illustrated radiological guide

International Nuclear Information System (INIS)

Al-Tubaikh, Jarrah Ali; Sabah Hospital, Kuwait

2010-01-01

This book explains how radiology can be a powerful tool for establishing the diagnosis of many internal medicine diseases that are usually diagnosed on the basis of their laboratory or clinical presentation. It is organized in the classic fashion for internal medicine books, with eleven chapters covering the different internal medicine specialties. Within these chapters, more than 450 diseases are considered, some of which are rarely encountered but are nonetheless significant. For each disease, radiological and clinical features are displayed in images and high-quality digital medical illustrations, and those differential diagnoses are identified that can be ruled out by imaging alone. In addition, the pathophysiology underlying the radiological features is described, enabling the reader to understand why a particular sign is seen on MR images, CT scans, or plain radiographs. The book will serve as an excellent radiological atlas for internal medicine practitioners and family physicians, showing disease presentations that may be hard to find in standard medical textbooks and explaining which imaging modalities are likely to be most informative in particular patients. (orig.)

Dynamic three-dimensional display of common congenital cardiac defects from reconstruction of two-dimensional echocardiographic images.

Science.gov (United States)

Hsieh, K S; Lin, C C; Liu, W S; Chen, F L

1996-01-01

Two-dimensional echocardiography had long been a standard diagnostic modality for congenital heart disease. Further attempts of three-dimensional reconstruction using two-dimensional echocardiographic images to visualize stereotypic structure of cardiac lesions have been successful only recently. So far only very few studies have been done to display three-dimensional anatomy of the heart through two-dimensional image acquisition because such complex procedures were involved. This study introduced a recently developed image acquisition and processing system for dynamic three-dimensional visualization of various congenital cardiac lesions. From December 1994 to April 1995, 35 cases were selected in the Echo Laboratory here from about 3000 Echo examinations completed. Each image was acquired on-line with specially designed high resolution image grazmber with EKG and respiratory gating technique. Off-line image processing using a window-architectured interactive software package includes construction of 2-D ehcocardiographic pixel to 3-D "voxel" with conversion of orthogonal to rotatory axial system, interpolation, extraction of region of interest, segmentation, shading and, finally, 3D rendering. Three-dimensional anatomy of various congenital cardiac defects was shown, including four cases with ventricular septal defects, two cases with atrial septal defects, and two cases with aortic stenosis. Dynamic reconstruction of a "beating heart" is recorded as vedio tape with video interface. The potential application of 3D display of the reconstruction from 2D echocardiographic images for the diagnosis of various congenital heart defects has been shown. The 3D display was able to improve the diagnostic ability of echocardiography, and clear-cut display of the various congenital cardiac defects and vavular stenosis could be demonstrated. Reinforcement of current techniques will expand future application of 3D display of conventional 2D images.

Exploring two-dimensional electron gases with two-dimensional Fourier transform spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Paul, J.; Dey, P.; Karaiskaj, D., E-mail: karaiskaj@usf.edu [Department of Physics, University of South Florida, 4202 East Fowler Ave., Tampa, Florida 33620 (United States); Tokumoto, T.; Hilton, D. J. [Department of Physics, University of Alabama at Birmingham, Birmingham, Alabama 35294 (United States); Reno, J. L. [CINT, Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

2014-10-07

The dephasing of the Fermi edge singularity excitations in two modulation doped single quantum wells of 12 nm and 18 nm thickness and in-well carrier concentration of ∼4 × 10{sup 11} cm{sup −2} was carefully measured using spectrally resolved four-wave mixing (FWM) and two-dimensional Fourier transform (2DFT) spectroscopy. Although the absorption at the Fermi edge is broad at this doping level, the spectrally resolved FWM shows narrow resonances. Two peaks are observed separated by the heavy hole/light hole energy splitting. Temperature dependent “rephasing” (S{sub 1}) 2DFT spectra show a rapid linear increase of the homogeneous linewidth with temperature. The dephasing rate increases faster with temperature in the narrower 12 nm quantum well, likely due to an increased carrier-phonon scattering rate. The S{sub 1} 2DFT spectra were measured using co-linear, cross-linear, and co-circular polarizations. Distinct 2DFT lineshapes were observed for co-linear and cross-linear polarizations, suggesting the existence of polarization dependent contributions. The “two-quantum coherence” (S{sub 3}) 2DFT spectra for the 12 nm quantum well show a single peak for both co-linear and co-circular polarizations.

Content Analysis of Primary and Secondary School Textbooks Regarding Malaria Control: A Multi-Country Study

Science.gov (United States)

Nonaka, Daisuke; Jimba, Masamine; Mizoue, Tetsuya; Kobayashi, Jun; Yasuoka, Junko; Ayi, Irene; Jayatilleke, Achini C.; Shrestha, Sabina; Kikuchi, Kimiyo; Haque, Syed E.; Yi, Siyan

2012-01-01

Background In tropical settings, malaria education at school is potentially useful, but textbook content related to malaria education has so far received little attention. This study aimed to examine whether school textbooks contain sufficient knowledge and skills to help children in primary and lower secondary schools and their family members to cope with malaria. Methodology/Principal Findings This was a descriptive, cross-country study. We collected textbooks that were used by children in grades one to nine from nine countries endemic for malaria: Laos, Cambodia, Nepal, Bangladesh, Sri Lanka, Zambia, Niger, Benin, and Ghana. Two reviewers per country identified descriptions about malaria by seeking the term “malaria” or a local word that corresponds to malaria in languages other than English. The authors categorized the identified descriptions according to the content of the descriptions. Additionally, the authors examined whether the identified contents addressed life skill messages. Of a total of 474 textbooks collected, 35 contained descriptions about malaria. The most commonly included content was transmission mode/vector (77.1%), followed by preventive measures (60.0%), epidemiology (57.1%), cause/agent (54.3%), signs/symptoms (37.1%) and treatment (22.9%). Treatment-related content was not included in any textbooks from four countries and textbooks failed to recommend the use of insecticide-treated bed nets in five countries. Very few textbooks included content that facilitated prompt treatment, protection of risk groups, and use of recommended therapy. Conclusion/Significance Textbooks rarely included knowledge and skills that are crucial to protect schoolchildren and their families from malaria. This study identified the need for improvement to textbook contents regarding malaria. PMID:22574203

Two-dimensional time dependent Riemann solvers for neutron transport

International Nuclear Information System (INIS)

Brunner, Thomas A.; Holloway, James Paul

2005-01-01

A two-dimensional Riemann solver is developed for the spherical harmonics approximation to the time dependent neutron transport equation. The eigenstructure of the resulting equations is explored, giving insight into both the spherical harmonics approximation and the Riemann solver. The classic Roe-type Riemann solver used here was developed for one-dimensional problems, but can be used in multidimensional problems by treating each face of a two-dimensional computation cell in a locally one-dimensional way. Several test problems are used to explore the capabilities of both the Riemann solver and the spherical harmonics approximation. The numerical solution for a simple line source problem is compared to the analytic solution to both the P 1 equation and the full transport solution. A lattice problem is used to test the method on a more challenging problem

On the ground state of the two-dimensional non-ideal Bose gas

International Nuclear Information System (INIS)

Lozovik, Yu.E.; Yudson, V.I.

1978-01-01

The theory of the ground state of the two-dimensional non-ideal Bose gas is presented. The conditions for the validity of the ladder and the Bogolubov approximations are derived. These conditions ensure the existence of a Bose condensate in the ground state of two-dimensional systems. These conditions are different from the corresponding conditions for the three-dimensional case. The connection between the effective interaction and the two-dimensional scattering amplitude at some characteristic energy kappa 2 /2m (not equal to 0) is obtained (f(kappa = 0) = infinity in the two-dimensional case). (Auth.)

Method for coupling two-dimensional to three-dimensional discrete ordinates calculations

International Nuclear Information System (INIS)

Thompson, J.L.; Emmett, M.B.; Rhoades, W.A.; Dodds, H.L. Jr.

1985-01-01

A three-dimensional (3-D) discrete ordinates transport code, TORT, has been developed at the Oak Ridge National Laboratory for radiation penetration studies. It is not feasible to solve some 3-D penetration problems with TORT, such as a building located a large distance from a point source, because (a) the discretized 3-D problem is simply too big to fit on the computer or (b) the computing time (and corresponding cost) is prohibitive. Fortunately, such problems can be solved with a hybrid approach by coupling a two-dimensional (2-D) description of the point source, which is assumed to be azimuthally symmetric, to a 3-D description of the building, the region of interest. The purpose of this paper is to describe this hybrid methodology along with its implementation and evaluation in the DOTTOR (Discrete Ordinates to Three-dimensional Oak Ridge Transport) code

Warranty menu design for a two-dimensional warranty

International Nuclear Information System (INIS)

Ye, Zhi-Sheng; Murthy, D.N. Pra

2016-01-01

Fierce competitions in the commercial product market have forced manufacturers to provide customer-friendly warranties with a view to achieving higher customer satisfaction and increasing the market share. This study proposes a strategy that offers customers a two-dimensional warranty menu with a number of warranty choices, called a flexible warranty policy. We investigate the design of a flexible two-dimensional warranty policy that contains a number of rectangular regions. This warranty policy is obtained by dividing customers into several groups according to their use rates and providing each group a germane warranty region. Consumers choose a favorable one from the menu according to their usage behaviors. Evidently, this flexible warranty policy is attractive to users of different usage behaviors, and thus, it gives the manufacturer a good position in advertising the product. When consumers are unaware about their use rates upon purchase, we consider a fixed two-dimensional warranty policy with a stair-case warranty region and show that it is equivalent to the flexible policy. Such an equivalence reveals the inherent relationship between the rectangular warranty policy, the L-shape warranty policy, the step-stair warranty policy and the iso-probability of failure warranty policy that were extensively discussed in the literature. - Highlights: • We design a two-dimensional warranty menu with a number of warranty choices. • Consumers can choose a favorable one from the menu as per their usage behavior. • We further consider a fixed 2D warranty policy with a stair-case warranty region. • We show the equivalence of the two warranty policies.

Textbooks in transitional countries: Towards a methodology for comparative analysis

Directory of Open Access Journals (Sweden)

Miha Kovač

2004-01-01

Full Text Available In its first part, the paper analyses the ambiguous nature of the book as a medium: its physical production and its distribution to the end user takes place on a market basis; on the other hand, its content is predominantly consumed in a sector that was at least in the continental Europe traditionally considered as public and non-profit making. This ambiguous nature of the book and with it the impact of the market on the organization of knowledge in book format remains a dark spot in contemporary book research. On the other hand, textbooks are considered as ephemera both in contemporary education and book studies. Therefore, research on textbooks publishing models could be considered as a blind-spot of contemporary social studies. As a consequence, in the majority of European countries, textbook publishing and the organization of the textbook market are considered as self-evident. Throughout a comparative analysis of textbook publishing models in small transitional and developed countries, the paper points out that this self-evident organization of the textbook market is always culturally determined. In its final part, the paper compares different models of textbook publishing and outlines the scenarios for the development of the Slovene textbook market.

Two-dimensional condensation of physi-sorbed methane on layer-like halides

International Nuclear Information System (INIS)

Nardon, Yves

1972-01-01

Two-dimensional condensation of methane in physi-sorbed layers has been studied from sets of stepped isotherms of methane on the cleavage plane of layer-like halides (FeCl 2 , CdCl 2 , NiBr 2 , CdBr 2 , FeI 2 , CaI 2 , CaI 2 and PbI 2 ) in most cases prepared by sublimation in a rapid current of inert gas. The vertical parts of the steps of adsorption isotherms correspond to the formation of successive monomolecular layers by two-dimensional condensation. Thermodynamic analysis of experimental results, has mainly emphasized the important effect of the potential relief of adsorbent surfaces, on both the structure of the physi-sorbed layers and the two-dimensional critical temperature. From its entropy, we conclude that the first layer is a (111) plane of f.c.c.: methane which becomes more loosely packed as the dimensional compatibility of the lattices of the adsorbent and adsorbate becomes poorer. Experimental values of the two-dimensional critical temperatures in the first, second and third layers have been determined, and interpreted on the following basis. An expansion of the layer induces a lowering of the two-dimensional critical temperature by decreasing the lateral interaction energy, while a localisation of the adsorbed molecules in potential wells, when possible, induces a rise of the two-dimensional critical temperature. (author) [fr

Emerging Technologies: E-Textbooks, One Piece of the Puzzle

Science.gov (United States)

Wiese, Melanie; Du Plessis, Giselle

2017-01-01

The Internet has not only brought about a new technological era, but also seen the introduction of a number of emerging technologies such as e-textbooks. However, the slow acceptance of e-textbooks is an issue of concern. The objective of this study is to investigate students' perceptions and use of e-textbooks. Data was collected by using a…

Islam and Muslim Life in Current Bavarian Geography Textbooks

Science.gov (United States)

Zecha, Stefanie; Popp, Stephan; Yasar, Aysun

2016-01-01

This paper investigates the Islam and Muslim life in German textbooks. The study is based on the analysis of current Geography textbooks in Bavarian secondary schools. As a first step, the authors developed a system for objective analysis of the textbooks that structures the content in categories. In a second step, the authors used the qualitative…

The Determinants of Electronic Textbook Use among College Students

Science.gov (United States)

Miller, Jon R.; Nutting, Andrew W.; Baker-Eveleth, Lori

2012-01-01

Electronic books are a fast-growing component of the publishing industry. Sales of electronic textbooks (e-textbooks) are growing, but at a slower rate. In this research we use data from an undergraduate student survey to estimate the determinants of e-textbook use. We find that students who are younger, lower-income, and from larger high schools…

"Essential Principles of Economics:" A Hypermedia Textbook.

Science.gov (United States)

McCain, Roger A.

2000-01-01

Discusses an electronic textbook called "Essential Principles of Economics." Explains that economic concepts are found by following links from the table of contents, while each chapter includes both expository information and interactive material including online multiple-choice drill questions. States that the textbook is a "work…

Conformal invariance and two-dimensional physics

International Nuclear Information System (INIS)

Zuber, J.B.

1993-01-01

Actually, physicists and mathematicians are very interested in conformal invariance: geometric transformations which keep angles. This symmetry is very important for two-dimensional systems as phase transitions, string theory or node mathematics. In this article, the author presents the conformal invariance and explains its usefulness

Corpus-Based Foreign-Language Textbooks : using the cognitive resources of older learners efficiently

Directory of Open Access Journals (Sweden)

Danya Ramírez-Gómez

2017-12-01

Full Text Available The presence of older learners (60 years old and over in the foreign language (FL classroom is increasingly common. However, although these students differ from younger ones in a variety of cognitive, physical and psychological aspects, textbooks have not yet been adapted to the characteristics of the former. This lack of teaching materials entails either that older learners be unable to study an FL with a textbook that addresses their needs and interests, or that teachers must constantly collect materials from different sources, which is exceedingly time consuming. The objective of this article is to start a debate on potential modifications to Spanish teaching materials that respond to older learners’ needs, specifically for initial level learners. This study discusses modifications that address two significant issues: the introduction of vocabulary, and the introduction of grammar tenses and conjugations. These two issues generate important challenges in the learning process of the cohort under discussion (Ramírez Gómez 2016. The framework for this work is the analysis of the Corpus del Español (Davies 2002, which includes more than 100 million entries. The study explores the most frequently used content words of Spanish (e.g. nouns, verbs, adjectives and contrasts these data with how current and popular Spanish textbooks introduce this information. The analysis indicates that textbooks present vocabulary and grammar tenses and conjugations in a manner that fails to reflect actual Spanish use, despite this being one of the main objectives of the functional-approach, which is followed by most of the textbooks revised here. Also, drawing from previous studies on age-related cognitive transformations, transitivity, aspect, among others, we argue that textbooks for initial level learners – particularly for older learners – should centre on the acquisition of highly frequent and relatable vocabulary to elevate their exposure to relevant

Multisoliton formula for completely integrable two-dimensional systems

International Nuclear Information System (INIS)

Chudnovsky, D.V.; Chudnovsky, G.V.

1979-01-01

For general two-dimensional completely integrable systems, the exact formulae for multisoliton type solutions are given. The formulae are obtained algebrically from solutions of two linear partial differential equations

It's Not Written Here, but This Is What Happened: Students' Cultural Comprehension of Textbook Narratives on the Israeli-Arab Conflict

Science.gov (United States)

Porat, Dan A.

2004-01-01

A group of Israeli high school students (h = 11) from two socially distinct schools read aloud a textbook account of a 1920 bloody encounter between Jews and Arabs. The study aimed at examining the relation between the textbook account and the students' formation of historical perceptions. Prior to reading the textbook excerpts, students wrote…

Assessing Prinary School; Second Cycle Social Science Textbooks ...

African Journals Online (AJOL)

Assessing Prinary School; Second Cycle Social Science Textbooks in ... second cycle primary level social science textbooks vis-à-vis the principles of multiculturalism. ... Biases were disclosed in gender, economic and occupational roles.

Textbook Development and Selection in Japan and the United States.

Science.gov (United States)

Tani, Masaru; And Others

1993-01-01

Reports on a study trip by 13 U.S. social studies educators and publishers to Japan. Compares development, marketing, and selection of textbooks in the United States and Japan. Concludes that both nations should improve textbooks and textbook selection processes. (CFR)

Critical Behaviour of a Two-Dimensional Random Antiferromagnet

DEFF Research Database (Denmark)

Als-Nielsen, Jens Aage; Birgeneau, R. J.; Guggenheim, H. J.

1976-01-01

A neutron scattering study of the order parameter, correlation length and staggered susceptibility of the two-dimensional random antiferromagnet Rb2Mn0.5Ni0.5F4 is reported. The system is found to exhibit a well-defined phase transition with critical exponents identical to those of the isomorphou...... pure materials K2NiF4 and K2MnF4. Thus, in these systems, which have the asymptotic critical behaviour of the two-dimensional Ising model, randomness has no measurable effect on the phase-transition behaviour....

Resource Exploitation and Consumption in the Frame of Education for Sustainable Development in German Geography Textbooks

Science.gov (United States)

Kowasch, Matthias

2017-01-01

This paper discusses the representation of resource exploitation and consumption in German geography textbooks. The aim of the paper is to contribute to a critical and reflective understanding of the representation of resource-related issues in textbooks by analyzing two scientific debates (resource curse and actor analysis). The paper shows that…

Representations of the Nature of Scientific Knowledge in Turkish Biology Textbooks

Science.gov (United States)

Irez, Serhat

2016-01-01

Considering the impact of textbooks on learning, this study set out to assess representations of the nature of scientific knowledge in Turkish 9th grade biology textbooks. To this end, the ten most commonly used 9th grade biology textbooks were analyzed. A qualitative research approach was utilized and the textbooks were analyzed using…

Reliability of tunnel angle in ACL reconstruction: two-dimensional versus three-dimensional guide technique.

Science.gov (United States)

Leiter, Jeff R S; de Korompay, Nevin; Macdonald, Lindsey; McRae, Sheila; Froese, Warren; Macdonald, Peter B

2011-08-01

To compare the reliability of tibial tunnel position and angle produced with a standard ACL guide (two-dimensional guide) or Howell 65° Guide (three-dimensional guide) in the coronal and sagittal planes. In the sagittal plane, the dependent variables were the angle of the tibial tunnel relative to the tibial plateau and the position of the tibial tunnel with respect to the most posterior aspect of the tibia. In the coronal plane, the dependent variables were the angle of the tunnel with respect to the medial joint line of the tibia and the medial and lateral placement of the tibial tunnel relative to the most medial aspect of the tibia. The position and angle of the tibial tunnel in the coronal and sagittal planes were determined from anteroposterior and lateral radiographs, respectively, taken 2-6 months postoperatively. The two-dimensional and three-dimensional guide groups included 28 and 24 sets of radiographs, respectively. Tibial tunnel position was identified, and tunnel angle measurements were completed. Multiple investigators measured the position and angle of the tunnel 3 times, at least 7 days apart. The angle of the tibial tunnel in the coronal plane using a two-dimensional guide (61.3 ± 4.8°) was more horizontal (P guide (64.7 ± 6.2°). The position of the tibial tunnel in the sagittal plane was more anterior (P guide group compared to the three-dimensional guide group (43.3 ± 2.9%). The Howell Tibial Guide allows for reliable placement of the tibial tunnel in the coronal plane at an angle of 65°. Tibial tunnels were within the anatomical footprint of the ACL with either technique. Future studies should investigate the effects of tibial tunnel angle on knee function and patient quality of life. Case-control retrospective comparative study, Level III.

Matching Two-dimensional Gel Electrophoresis' Spots

DEFF Research Database (Denmark)

Dos Anjos, António; AL-Tam, Faroq; Shahbazkia, Hamid Reza

2012-01-01

This paper describes an approach for matching Two-Dimensional Electrophoresis (2-DE) gels' spots, involving the use of image registration. The number of false positive matches produced by the proposed approach is small, when compared to academic and commercial state-of-the-art approaches. This ar...

Rational solutions to two- and one-dimensional multicomponent Yajima–Oikawa systems

International Nuclear Information System (INIS)

Chen, Junchao; Chen, Yong; Feng, Bao-Feng; Maruno, Ken-ichi

2015-01-01

Exact explicit rational solutions of two- and one-dimensional multicomponent Yajima–Oikawa (YO) systems, which contain multi-short-wave components and single long-wave one, are presented by using the bilinear method. For two-dimensional system, the fundamental rational solution first describes the localized lumps, which have three different patterns: bright, intermediate and dark states. Then, rogue waves can be obtained under certain parameter conditions and their behaviors are also classified to above three patterns with different definition. It is shown that the simplest (fundamental) rogue waves are line localized waves which arise from the constant background with a line profile and then disappear into the constant background again. In particular, two-dimensional intermediate and dark counterparts of rogue wave are found with the different parameter requirements. We demonstrate that multirogue waves describe the interaction of several fundamental rogue waves, in which interesting curvy wave patterns appear in the intermediate times. Different curvy wave patterns form in the interaction of different types fundamental rogue waves. Higher-order rogue waves exhibit the dynamic behaviors that the wave structures start from lump and then retreat back to it, and this transient wave possesses the patterns such as parabolas. Furthermore, different states of higher-order rogue wave result in completely distinguishing lumps and parabolas. Moreover, one-dimensional rogue wave solutions with three states are constructed through the further reduction. Specifically, higher-order rogue wave in one-dimensional case is derived under the parameter constraints. - Highlights: • Exact explicit rational solutions of two-and one-dimensional multicomponent Yajima–Oikawa systems. • Two-dimensional rogue wave contains three different patterns: bright, intermediate and dark states. • Multi- and higher-order rogue waves exhibit distinct dynamic behaviors in two-dimensional case

Manifestations of Globalization and Linguistic Imperialism in English Language Teaching and Materials Preparation: Ideology in the International ELT Textbooks

Directory of Open Access Journals (Sweden)

Seyyed Ali Kazemi

2017-09-01

Full Text Available This study intended to investigate the imposition of values and ideological patterns of particular societies affecting learners' identity as a result of globalization and linguistic imperialism in the internationally distributed textbooks which are developed to meet the English language needs of international learners and are broadly used in Islamic countries like Iran. It was important to work out whether violation of standards and ideological patterns of certain societies could be detected. For that reason, critical discourse analysis (CDA with its theory and procedures, as developed by Fairclough (1989, used in conversations, illustrations and reading passages in Interchange, Four Corners, Top Notch and American English File series and three meaning dimensions– the textbooks content, the social relations of the characters in the textbooks, and their subject positions– were classified and analyzed statistically. Overall, the findings of this study represented that these ELT books are by some means unfair and inclined to signify a specific discourse type, that is, the Western culture discourse, ideological patterns, and consumer societies, which can impose the Western view and have different effects on students' identity in Islamic countries.

Two-dimensional sensitivity calculation code: SENSETWO

International Nuclear Information System (INIS)

Yamauchi, Michinori; Nakayama, Mitsuo; Minami, Kazuyoshi; Seki, Yasushi; Iida, Hiromasa.

1979-05-01

A SENSETWO code for the calculation of cross section sensitivities with a two-dimensional model has been developed, on the basis of first order perturbation theory. It uses forward neutron and/or gamma-ray fluxes and adjoint fluxes obtained by two-dimensional discrete ordinates code TWOTRAN-II. The data and informations of cross sections, geometry, nuclide density, response functions, etc. are transmitted to SENSETWO by the dump magnetic tape made in TWOTRAN calculations. The required input for SENSETWO calculations is thus very simple. The SENSETWO yields as printed output the cross section sensitivities for each coarse mesh zone and for each energy group, as well as the plotted output of sensitivity profiles specified by the input. A special feature of the code is that it also calculates the reaction rate with the response function used as the adjoint source in TWOTRAN adjoint calculation and the calculated forward flux from the TWOTRAN forward calculation. (author)

Textbooks for Responsible Data Analysis in Excel

Science.gov (United States)

Garrett, Nathan

2015-01-01

With 27 million users, Excel (Microsoft Corporation, Seattle, WA) is the most common business data analysis software. However, audits show that almost all complex spreadsheets have errors. The author examined textbooks to understand why responsible data analysis is taught. A purposeful sample of 10 textbooks was coded, and then compared against…

Principles of Economics Textbooks: Innovation and Product Differentiation--A Response.

Science.gov (United States)

Sichel, Werner

1988-01-01

Focusing on areas of contention, the author responds to "Principles of Economics Textbooks: Innovation and Product Differentiation" by Stiglitz. Contends that Stiglitz's description of principles textbooks is insufficient, states that the textbook market is more oligopolistic than monopolistic, and cautions writers against deleting parts…

High-velocity two-phase flow two-dimensional modeling

International Nuclear Information System (INIS)

Mathes, R.; Alemany, A.; Thilbault, J.P.

1995-01-01

The two-phase flow in the nozzle of a LMMHD (liquid metal magnetohydrodynamic) converter has been studied numerically and experimentally. A two-dimensional model for two-phase flow has been developed including the viscous terms (dragging and turbulence) and the interfacial mass, momentum and energy transfer between the phases. The numerical results were obtained by a finite volume method based on the SIMPLE algorithm. They have been verified by an experimental facility using air-water as a simulation pair and a phase Doppler particle analyzer for velocity and droplet size measurement. The numerical simulation of a lithium-cesium high-temperature pair showed that a nearly homogeneous and isothermal expansion of the two phases is possible with small pressure losses and high kinetic efficiencies. In the throat region a careful profiling is necessary to reduce the inertial effects on the liquid velocity field

Extinction maps toward the Milky Way bulge: Two-dimensional and three-dimensional tests with apogee

Energy Technology Data Exchange (ETDEWEB)

Schultheis, M. [Université de Nice Sophia-Antipolis, CNRS, Observatoire de Côte d' Azur, Laboratoire Lagrange, 06304 Nice Cedex 4 (France); Zasowski, G. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Allende Prieto, C. [Instituto de Astrofísica de Canarias, Calle Vía Láctea s/n, E-38205 La Laguna, Tenerife (Spain); Anders, F.; Chiappini, C. [Leibniz-Institut für Astrophysik Potsdam (AIP), D-14482 Potsdam (Germany); Beaton, R. L.; García Pérez, A. E.; Majewski, S. R. [Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States); Beers, T. C. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Bizyaev, D. [Apache Point Observatory, Sunspot, NM 88349 (United States); Frinchaboy, P. M. [Department of Physics and Astronomy, Texas Christian University, TCU Box 298840, Fort Worth, TX 76129 (United States); Ge, J. [Astronomy Department, University of Florida, Gainesville, FL 32611 (United States); Hearty, F.; Schneider, D. P. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Holtzman, J. [New Mexico State University, Las Cruces, NM 88003 (United States); Muna, D. [Department of Astronomy, The Ohio State University, Columbus, OH 43210 (United States); Nidever, D. [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Shetrone, M., E-mail: mathias.schultheis@oca.eu, E-mail: gail.zasowski@gmail.com [McDonald Observatory, The University of Texas at Austin, Austin, TX 78712 (United States)

2014-07-01

Galactic interstellar extinction maps are powerful and necessary tools for Milky Way structure and stellar population analyses, particularly toward the heavily reddened bulge and in the midplane. However, due to the difficulty of obtaining reliable extinction measures and distances for a large number of stars that are independent of these maps, tests of their accuracy and systematics have been limited. Our goal is to assess a variety of photometric stellar extinction estimates, including both two-dimensional and three-dimensional extinction maps, using independent extinction measures based on a large spectroscopic sample of stars toward the Milky Way bulge. We employ stellar atmospheric parameters derived from high-resolution H-band Apache Point Observatory Galactic Evolution Experiment (APOGEE) spectra, combined with theoretical stellar isochrones, to calculate line-of-sight extinction and distances for a sample of more than 2400 giants toward the Milky Way bulge. We compare these extinction values to those predicted by individual near-IR and near+mid-IR stellar colors, two-dimensional bulge extinction maps, and three-dimensional extinction maps. The long baseline, near+mid-IR stellar colors are, on average, the most accurate predictors of the APOGEE extinction estimates, and the two-dimensional and three-dimensional extinction maps derived from different stellar populations along different sightlines show varying degrees of reliability. We present the results of all of the comparisons and discuss reasons for the observed discrepancies. We also demonstrate how the particular stellar atmospheric models adopted can have a strong impact on this type of analysis, and discuss related caveats.

Extinction maps toward the Milky Way bulge: Two-dimensional and three-dimensional tests with apogee

International Nuclear Information System (INIS)

Schultheis, M.; Zasowski, G.; Allende Prieto, C.; Anders, F.; Chiappini, C.; Beaton, R. L.; García Pérez, A. E.; Majewski, S. R.; Beers, T. C.; Bizyaev, D.; Frinchaboy, P. M.; Ge, J.; Hearty, F.; Schneider, D. P.; Holtzman, J.; Muna, D.; Nidever, D.; Shetrone, M.

2014-01-01

Galactic interstellar extinction maps are powerful and necessary tools for Milky Way structure and stellar population analyses, particularly toward the heavily reddened bulge and in the midplane. However, due to the difficulty of obtaining reliable extinction measures and distances for a large number of stars that are independent of these maps, tests of their accuracy and systematics have been limited. Our goal is to assess a variety of photometric stellar extinction estimates, including both two-dimensional and three-dimensional extinction maps, using independent extinction measures based on a large spectroscopic sample of stars toward the Milky Way bulge. We employ stellar atmospheric parameters derived from high-resolution H-band Apache Point Observatory Galactic Evolution Experiment (APOGEE) spectra, combined with theoretical stellar isochrones, to calculate line-of-sight extinction and distances for a sample of more than 2400 giants toward the Milky Way bulge. We compare these extinction values to those predicted by individual near-IR and near+mid-IR stellar colors, two-dimensional bulge extinction maps, and three-dimensional extinction maps. The long baseline, near+mid-IR stellar colors are, on average, the most accurate predictors of the APOGEE extinction estimates, and the two-dimensional and three-dimensional extinction maps derived from different stellar populations along different sightlines show varying degrees of reliability. We present the results of all of the comparisons and discuss reasons for the observed discrepancies. We also demonstrate how the particular stellar atmospheric models adopted can have a strong impact on this type of analysis, and discuss related caveats.

Two dimensional unstable scar statistics.

Energy Technology Data Exchange (ETDEWEB)

Warne, Larry Kevin; Jorgenson, Roy Eberhardt; Kotulski, Joseph Daniel; Lee, Kelvin S. H. (ITT Industries/AES Los Angeles, CA)

2006-12-01

This report examines the localization of time harmonic high frequency modal fields in two dimensional cavities along periodic paths between opposing sides of the cavity. The cases where these orbits lead to unstable localized modes are known as scars. This paper examines the enhancements for these unstable orbits when the opposing mirrors are both convex and concave. In the latter case the construction includes the treatment of interior foci.

TECHNOLOGY FOR DEVELOPMENT OF ELECTRONIC TEXTBOOK ON HANDICRAFTS METHODOLOGY

Directory of Open Access Journals (Sweden)

Iryna V. Androshchuk

2017-10-01

Full Text Available The main approaches to defining the concept of electronic textbook have been analyzed in the article. The main advantages of electronic textbooks in the context of future teachers’ training have been outlined. They are interactivity, feedback provision, availability of navigation and search engine. The author has presented and characterized the main stages in the technology of development of an electronic textbook on Handicraft and Technology Training Methodology: determination of its role and significance in the process of mastering the discipline; justification of its structure; outline of the stages of its development in accordance with the defined structure. The characteristic feature of the developed electronic textbook is availability of macro- and microstructure. Macrostructure is viewed as a sequence of components of the electronic textbook that are manifested in its content; microstructure is considered to be an internal pattern of each component of macrostructure.

Chemical term correspondence between Japanese and American chemistry textbooks. II. Nippon to America no kagaku kyokasho ni okeru kagaku yogo no taio. II

Energy Technology Data Exchange (ETDEWEB)

Kakihara, S. (Hiroshima University, Hiroshima (Japan))

1991-06-10

This is a study on how chemical terms used in Japanese chemistry textbooks correspond to those in American textbooks. Examples in which English and Japanese chemical terms do not correspond are divided into 4 groups, and points to be noticed are described. As references, two kinds of most popular textbooks in the U.S. and three kinds of Japanese textbooks are mainly used. When chemical terms in either of American or Japanese textbooks do not correspond to or were not found in the other textbooks, several kinds of other dictionaries and textbooks are also investigated. As a result, it is found that there are some English terms which are apt to be mistranslated into Japanese. Some of English translations established in dictionaries and textbooks in Japan are not found in American textbooks. In the same way, some English terms often used in American textbooks do not appear in Japanese textbooks and dictionaries. These examples and notes seem to be useful for reading American textbooks or writing English abstracts of papers on chemistry. 16 refs.

[Characteristics of acupuncture textbooks on editing mode and content in the Republic of China].

Science.gov (United States)

Zhao, Jing; Zhang, Shujian

2017-09-12

Sixty-seven textbooks in the Republic of China have been collected and divided into three stages according to their editing modes, named the early stage (1912-1927), the middle stage (1928-1939) and the late stage (1940-1949). The traditional teaching material of acupuncture was predominated at the early stage in the textbook compilation; meanwhile the editing mode was simple, and the content of it focuses on meridians, collaterals and acupoints and the modern scientific theories have been preliminarily introduced. The textbooks at the middle stage were edited as two modes, "western medicine+acupuncture" and "general introduction→meridian points→manipulation (techniques of acupuncture and moxibustion)→treatment". The knowledge in anatomy, physiology and pathology of western medicine has been involved in content, giving the great consideration to the clinical practicability. However, a part of textbooks still followed the traditional theory of acupuncture at the middle stage. At the late stage, the textbooks were edited align with "acupuncture science, moxibustion science, meridian point science and treatment science"; or in supplementation of the "diagnosis" on the base of "general introduction→ meridian points→techniques of acupuncture→treatment", or edited as "general introduction→points→treatment". The compilation of the textbooks at this stage not only followed but also improved the integration of western and Chinese medicine as that at the middle stage, which turned to be more scientific. Additionally, in the teaching content, the acupoint was much more considerable as compared with pulse and the section of diagnosis has been involved. As a result, a framework of acupuncture discipline has been established preliminarily by taking acupuncture technique, moxibustion technique, acupoints and treatment as the core. The development of the editing mode and content of textbooks played a great impact on the unified compilation of the acupuncture

Temperature maxima in stable two-dimensional shock waves

International Nuclear Information System (INIS)

Kum, O.; Hoover, W.G.; Hoover, C.G.

1997-01-01

We use molecular dynamics to study the structure of moderately strong shock waves in dense two-dimensional fluids, using Lucy pair potential. The stationary profiles show relatively broad temperature maxima, for both the longitudinal and the average kinetic temperatures, just as does Mott-Smith model for strong shock waves in dilute three-dimensional gases. copyright 1997 The American Physical Society

Tuning spin transport across two-dimensional organometallic junctions

Science.gov (United States)

Liu, Shuanglong; Wang, Yun-Peng; Li, Xiangguo; Fry, James N.; Cheng, Hai-Ping

2018-01-01

We study via first-principles modeling and simulation two-dimensional spintronic junctions made of metal-organic frameworks consisting of two Mn-phthalocyanine ferromagnetic metal leads and semiconducting Ni-phthalocyanine channels of various lengths. These systems exhibit a large tunneling magnetoresistance ratio; the transmission functions of such junctions can be tuned using gate voltage by three orders of magnitude. We find that the origin of this drastic change lies in the orbital alignment and hybridization between the leads and the center electronic states. With physical insight into the observed on-off phenomenon, we predict a gate-controlled spin current switch based on two-dimensional crystallines and offer general guidelines for designing spin junctions using 2D materials.

CORPORATE VALUATION USING TWO-DIMENSIONAL MONTE CARLO SIMULATION

Directory of Open Access Journals (Sweden)

Toth Reka

2010-12-01

Full Text Available In this paper, we have presented a corporate valuation model. The model combine several valuation methods in order to get more accurate results. To determine the corporate asset value we have used the Gordon-like two-stage asset valuation model based on the calculation of the free cash flow to the firm. We have used the free cash flow to the firm to determine the corporate market value, which was calculated with use of the Black-Scholes option pricing model in frame of the two-dimensional Monte Carlo simulation method. The combined model and the use of the two-dimensional simulation model provides a better opportunity for the corporate value estimation.

Marketing mix - project of a textbook for business academies

OpenAIRE

Zatloukalová, Zuzana

2010-01-01

The thesis deals with project of a textbook for business academies. The theme of the chapter of the textbook is marketing mix. The project is made in such a way the students get total information on these problems. The extant of the theme is intended for students of higher classes. The project consists of theoretical part (textbook, exercise book) and practical part (teaching at business academy).

Open Introductory Psychology Textbooks: Prose and Qualms

Science.gov (United States)

Griggs, Richard A.; Jackson, Sherri L.

2017-01-01

Given their high cost, many students no longer buy textbooks for all of their courses, impacting their learning and performance in these courses. This is especially prevalent at community colleges. Open (digitally free) textbooks constitute one solution to this problem, but the latest national survey of college faculty found that 66% were not…

46 CFR 310.63 - Uniforms and textbooks.

Science.gov (United States)

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false Uniforms and textbooks. 310.63 Section 310.63 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRAINING MERCHANT MARINE TRAINING Admission and Training of Midshipmen at the United States Merchant Marine Academy § 310.63 Uniforms and textbooks. The Academy shall supply midshipmen uniforms an...

Communicating Physics and the Design of Textbooks.

Science.gov (United States)

Barojas, Jorge; Trigueros, Maria

1991-01-01

The planning of an introductory calculus textbook in classical mechanics is shown as an example of an approach to textbook design that uses four main cognitive categories: sources of learning, instruments of learning, processes of knowing, and mechanisms of knowing. The aspects, domains, description, and elements of each section of the textbook…

Laser sheet dropsizing based on two-dimensional Raman and Mie scattering.

Science.gov (United States)

Malarski, Anna; Schürer, Benedikt; Schmitz, Ingo; Zigan, Lars; Flügel, Alexandre; Leipertz, Alfred

2009-04-01

The imaging and quantification of droplet sizes in sprays is a challenging task for optical scientists and engineers. Laser sheet dropsizing (LSDS) combines the two-dimensional information of two different optical processes, one that is proportional to the droplet volume and one that depends on the droplet surface, e.g., Mie scattering. Besides Mie scattering, here we use two-dimensional Raman scattering as the volume-dependent measurement technique. Two different calibration strategies are presented and discussed. Two-dimensional droplet size distributions in a spray have been validated in comparison with the results of point-resolved phase Doppler anemometry (PDA) measurements.

Laser sheet dropsizing based on two-dimensional Raman and Mie scattering

International Nuclear Information System (INIS)

Malarski, Anna; Schuerer, Benedikt; Schmitz, Ingo; Zigan, Lars; Fluegel, Alexandre; Leipertz, Alfred

2009-01-01

The imaging and quantification of droplet sizes in sprays is a challenging task for optical scientists and engineers. Laser sheet dropsizing (LSDS) combines the two-dimensional information of two different optical processes, one that is proportional to the droplet volume and one that depends on the droplet surface, e.g., Mie scattering. Besides Mie scattering, here we use two-dimensional Raman scattering as the volume-dependent measurement technique. Two different calibration strategies are presented and discussed. Two-dimensional droplet size distributions in a spray have been validated in comparison with the results of point-resolved phase Doppler anemometry (PDA) measurements

Towards Development of OER Derived Custom-Built Open Textbooks: A Baseline Survey of University Teachers at the University of the South Pacific

Directory of Open Access Journals (Sweden)

Deepak Prasad

2014-09-01

Full Text Available Textbook prices have soared over the years, with several studies revealing many university students are finding it difficult to afford textbooks. Fortunately, two innovations – open educational resources (OER and open textbooks – hold the potential to increase textbook affordability. Experts, though, have stated the obvious: that students can save money through open textbooks only if teachers are willing to develop and use them. Considering both the high price of textbooks and the benefits offered by OER and open textbooks, the aim of this study was to assess the University of the South Pacific (USP teachers’ willingness towards development of custom-built OER derived open textbooks for their courses with a focus on providing a foundation for strategies to promote open textbook development at USP. This paper reports the findings of an online survey of 39 USP teachers. The results show that 17 teachers were willing to develop OER derived custom-built open textbooks for their courses. Besides this, there are findings relating to six important areas: teachers’ motivation to develop open textbooks; the frequency of more than one prescribed textbook per course; teachers’ awareness of the costs of the prescribed textbooks; the average cost of prescribed textbooks in a course; teachers’ awareness and utilization of OER and open textbooks; and teachers’ perceived barriers to using OER and types of challenges they encounter while using OER. These findings have been discussed in relation to research studies on OER and open textbooks.

Automated Processing of Two-Dimensional Correlation Spectra

Science.gov (United States)

Sengstschmid; Sterk; Freeman

1998-04-01

An automated scheme is described which locates the centers of cross peaks in two-dimensional correlation spectra, even under conditions of severe overlap. Double-quantum-filtered correlation (DQ-COSY) spectra have been investigated, but the method is also applicable to TOCSY and NOESY spectra. The search criterion is the intrinsic symmetry (or antisymmetry) of cross-peak multiplets. An initial global search provides the preliminary information to build up a two-dimensional "chemical shift grid." All genuine cross peaks must be centered at intersections of this grid, a fact that reduces the extent of the subsequent search program enormously. The program recognizes cross peaks by examining the symmetry of signals in a test zone centered at a grid intersection. This "symmetry filter" employs a "lowest value algorithm" to discriminate against overlapping responses from adjacent multiplets. A progressive multiplet subtraction scheme provides further suppression of overlap effects. The processed two-dimensional correlation spectrum represents cross peaks as points at the chemical shift coordinates, with some indication of their relative intensities. Alternatively, the information is presented in the form of a correlation table. The authenticity of a given cross peak is judged by a set of "confidence criteria" expressed as numerical parameters. Experimental results are presented for the 400-MHz double-quantum-filtered COSY spectrum of 4-androsten-3,17-dione, a case where there is severe overlap. Copyright 1998 Academic Press.

Supporting Classroom Instruction: The Textbook Navigator/Journal

Science.gov (United States)

Cogan, Leland S.; Burroughs, Nathan; Schmidt, William H.

2015-01-01

Researchers at the Center for the Study of Curriculum at Michigan State University have developed a tool to help teachers implement the Common Core State Standards in mathematics by letting standards, not textbooks, guide their instruction. Using the web-based Textbook Navigator/Journal, teachers can pick a standard and ask which portions of the…

Sums of two-dimensional spectral triples

DEFF Research Database (Denmark)

Christensen, Erik; Ivan, Cristina

2007-01-01

construct a sum of two dimensional modules which reflects some aspects of the topological dimensions of the compact metric space, but this will only give the metric back approximately. At the end we make an explicit computation of the last module for the unit interval in. The metric is recovered exactly...

New hybrid lead iodides: From one-dimensional chain to two-dimensional layered perovskite structure

International Nuclear Information System (INIS)

Xiong, Kecai; Liu, Wei; Teat, Simon J.; An, Litao; Wang, Hao; Emge, Thomas J.; Li, Jing

2015-01-01

Two new hybrid lead halides (H 2 BDA)[PbI 4 ] (1) (H 2 BDA=1,4-butanediammonium dication) and (HNPEIM)[PbI 3 ] (2) (HNPEIM=N-​phenyl-ethanimidamidine cation) have been synthesized and structurally characterized. X-ray diffraction analyses reveal that compound 1 features a two-dimensional corner-sharing perovskite layer whereas compound 2 contains one-dimensional edge-sharing double chains. The N-​phenyl-ethanimidamidine cation within compound 2 was generated in-situ under solvothermal conditions. The optical absorption spectra collected at room temperature suggest that both compounds are semiconductors having direct band gaps, with estimated values of 2.64 and 2.73 eV for 1 and 2, respectively. Results from the density functional theory (DFT) calculations are consistent with the experimental data. Density of states (DOS) analysis reveals that in both compounds 1 and 2, the energy states in the valence band maximum region are iodine 5p atomic orbitals with a small contribution from lead 6s, while in the region of conduction band minimum, the major contributions are from the inorganic (Pb 6p atomic orbitals) and organic components (C and N 2p atomic orbitals) in compound 1 and 2, respectively. - Graphical abstract: Two new hybrid lead halides built on one-dimensional edge-sharing double chains and two-dimensional corner-sharing perovskite layers are synthesized and their structural and electronic properties are analyzed. - Highlights: • Two new hybrid lead iodides are designed, synthesized, and characterized. • They are closely related to, but different from, perovskite structures. • The electronic properties of both compounds are analyzed by DFT calculations

New hybrid lead iodides: From one-dimensional chain to two-dimensional layered perovskite structure

Energy Technology Data Exchange (ETDEWEB)

Xiong, Kecai; Liu, Wei [Department of Chemistry and Chemical Biology, Rutgers University, 610 Taylor Road, Piscataway, NJ 08854 (United States); Teat, Simon J. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); An, Litao; Wang, Hao; Emge, Thomas J. [Department of Chemistry and Chemical Biology, Rutgers University, 610 Taylor Road, Piscataway, NJ 08854 (United States); Li, Jing, E-mail: jingli@rutgers.edu [Department of Chemistry and Chemical Biology, Rutgers University, 610 Taylor Road, Piscataway, NJ 08854 (United States)

2015-10-15

Two new hybrid lead halides (H{sub 2}BDA)[PbI{sub 4}] (1) (H{sub 2}BDA=1,4-butanediammonium dication) and (HNPEIM)[PbI{sub 3}] (2) (HNPEIM=N-​phenyl-ethanimidamidine cation) have been synthesized and structurally characterized. X-ray diffraction analyses reveal that compound 1 features a two-dimensional corner-sharing perovskite layer whereas compound 2 contains one-dimensional edge-sharing double chains. The N-​phenyl-ethanimidamidine cation within compound 2 was generated in-situ under solvothermal conditions. The optical absorption spectra collected at room temperature suggest that both compounds are semiconductors having direct band gaps, with estimated values of 2.64 and 2.73 eV for 1 and 2, respectively. Results from the density functional theory (DFT) calculations are consistent with the experimental data. Density of states (DOS) analysis reveals that in both compounds 1 and 2, the energy states in the valence band maximum region are iodine 5p atomic orbitals with a small contribution from lead 6s, while in the region of conduction band minimum, the major contributions are from the inorganic (Pb 6p atomic orbitals) and organic components (C and N 2p atomic orbitals) in compound 1 and 2, respectively. - Graphical abstract: Two new hybrid lead halides built on one-dimensional edge-sharing double chains and two-dimensional corner-sharing perovskite layers are synthesized and their structural and electronic properties are analyzed. - Highlights: • Two new hybrid lead iodides are designed, synthesized, and characterized. • They are closely related to, but different from, perovskite structures. • The electronic properties of both compounds are analyzed by DFT calculations.

Introduction: The secret lives of textbooks.

Science.gov (United States)

Vicedo, Marga

2012-03-01

Textbooks have a low status in the history of science because they have been seen as mere repositories for scientific knowledge. But historians have recently shown how they play a number of roles that can illuminate different aspects of the history of science, from priority disputes to pedagogical practices. The essays in this Focus section aim to expand our vision of textbooks further by showing how they perform various hybrid functions in scientific development.

Pair Interaction of Dislocations in Two-Dimensional Crystals

Science.gov (United States)

Eisenmann, C.; Gasser, U.; Keim, P.; Maret, G.; von Grünberg, H. H.

2005-10-01

The pair interaction between crystal dislocations is systematically explored by analyzing particle trajectories of two-dimensional colloidal crystals measured by video microscopy. The resulting pair energies are compared to Monte Carlo data and to predictions derived from the standard Hamiltonian of the elastic theory of dislocations. Good agreement is found with respect to the distance and temperature dependence of the interaction potential, but not regarding the angle dependence where discrete lattice effects become important. Our results on the whole confirm that the dislocation Hamiltonian allows a quantitative understanding of the formation and interaction energies of dislocations in two-dimensional crystals.

Three-dimensional versus two-dimensional vision in laparoscopy

DEFF Research Database (Denmark)

Sørensen, Stine D; Savran, Mona Meral; Konge, Lars

2016-01-01

were cohort size and characteristics, skill trained or operation performed, instrument used, outcome measures, and conclusions. Two independent authors performed the search and data extraction. RESULTS: Three hundred and forty articles were screened for eligibility, and 31 RCTs were included...... through a two-dimensional (2D) projection on a monitor, which results in loss of depth perception. To counter this problem, 3D imaging for laparoscopy was developed. A systematic review of the literature was performed to assess the effect of 3D laparoscopy. METHODS: A systematic search of the literature...... in the review. Three trials were carried out in a clinical setting, and 28 trials used a simulated setting. Time was used as an outcome measure in all of the trials, and number of errors was used in 19 out of 31 trials. Twenty-two out of 31 trials (71 %) showed a reduction in performance time, and 12 out of 19...

Self-focusing instability of two-dimensional solitons and vortices

DEFF Research Database (Denmark)

Kuznetsov, E.A.; Juul Rasmussen, J.

1995-01-01

The instability of two-dimensional solitons and vortices is demonstrated in the framework of the three-dimensional nonlinear Schrodinger equation (NLSE). The instability can be regarded as the analog of the Kadomtsev-Petviashvili instability [B. B. Kadomtsev and V. I. Petviashvili, Sov. Phys. Dokl...

The effectiveness of an interactive 3-dimensional computer graphics model for medical education.

Science.gov (United States)

Battulga, Bayanmunkh; Konishi, Takeshi; Tamura, Yoko; Moriguchi, Hiroki

2012-07-09

Medical students often have difficulty achieving a conceptual understanding of 3-dimensional (3D) anatomy, such as bone alignment, muscles, and complex movements, from 2-dimensional (2D) images. To this end, animated and interactive 3-dimensional computer graphics (3DCG) can provide better visual information to users. In medical fields, research on the advantages of 3DCG in medical education is relatively new. To determine the educational effectiveness of interactive 3DCG. We divided 100 participants (27 men, mean (SD) age 17.9 (0.6) years, and 73 women, mean (SD) age 18.1 (1.1) years) from the Health Sciences University of Mongolia (HSUM) into 3DCG (n = 50) and textbook-only (control) (n = 50) groups. The control group used a textbook and 2D images, while the 3DCG group was trained to use the interactive 3DCG shoulder model in addition to a textbook. We conducted a questionnaire survey via an encrypted satellite network between HSUM and Tokushima University. The questionnaire was scored on a 5-point Likert scale from strongly disagree (score 1) to strongly agree (score 5). Interactive 3DCG was effective in undergraduate medical education. Specifically, there was a significant difference in mean (SD) scores between the 3DCG and control groups in their response to questionnaire items regarding content (4.26 (0.69) vs 3.85 (0.68), P = .001) and teaching methods (4.33 (0.65) vs 3.74 (0.79), P < .001), but no significant difference in the Web category. Participants also provided meaningful comments on the advantages of interactive 3DCG. Interactive 3DCG materials have positive effects on medical education when properly integrated into conventional education. In particular, our results suggest that interactive 3DCG is more efficient than textbooks alone in medical education and can motivate students to understand complex anatomical structures.

Student Perceptions of Textbook Layout and Learnability in Private Schools

Science.gov (United States)

Hoshangabadwala, Alefiyah

2015-01-01

This research is an exploratory study that investigates students' perceptions pertinent to textbook layout and organization and their evaluation of the textbook ease of learning. The objective is to find out whether the layout dynamics of school textbooks make any difference in students' interest in studying or subject understanding. 73 students…

Finally, nuclear engineering textbooks with a Canadian flavour{exclamation_point}

Energy Technology Data Exchange (ETDEWEB)

Bonin, H.W. [Royal Military College of Canada, Dept. of Chemistry and Chemical Engineering, Kingston, Ontario (Canada)

2002-07-01

The need for nuclear engineering textbooks more appropriate to the Canadian nuclear industry context and the CANDU nuclear reactor program has long been felt not only among the universities offering nuclear engineering programs at the graduate level, but also within the Canadian nuclear industry itself. Coverage of the CANDU reactor system in the textbooks presently supporting teaching is limited to a brief description of the concept. Course instructors usually complement these textbooks with course notes written from their personal experience from past employment within the nuclear industry and from their research interests In the last ten years, the Canadian nuclear industry has been involved on an increasing basis with the issue of the technology transfer to foreign countries which have purchased CANDU reactors or have been in the process of purchasing one or several CANDUs. For some of these countries, the 'turn key' approach is required, in which the Canadian nuclear industry looks after everything up to the commissioning of the nuclear power plant, including the education and training of local nuclear engineers and plant personnel. Atomic Energy of Canada Limited (AECL) in particular has dispatched some personnel tasked to prepare and give short courses on some specific aspects of CANDU design and operation, but a lack of consistency was observed as different persons prepared and gave the courses rather independently. To address the many problems tied with nuclear engineering education, the CANTEACH program was set up involving major partners of the Canadian nuclear industry. Parts of the activities foreseen by CANTEACH consist in the writing of nuclear engineering textbooks and associated computer-based pedagogical material. The present paper discusses the main parts of two textbooks being produced, one in reactor physics at steady state and the other on nuclear fuel management. (author)

Misrepresentations of evolutionary psychology in sex and gender textbooks.

Science.gov (United States)

Winegard, Benjamin M; Winegard, Bo M; Deaner, Robert O

2014-05-20

Evolutionary psychology has provoked controversy, especially when applied to human sex differences. We hypothesize that this is partly due to misunderstandings of evolutionary psychology that are perpetuated by undergraduate sex and gender textbooks. As an initial test of this hypothesis, we develop a catalog of eight types of errors and document their occurrence in 15 widely used sex and gender textbooks. Consistent with our hypothesis, of the 12 textbooks that discussed evolutionary psychology, all contained at least one error, and the median number of errors was five. The most common types of errors were "Straw Man," "Biological Determinism," and "Species Selection." We conclude by suggesting improvements to undergraduate sex and gender textbooks.

25 CFR 36.41 - Standard XIV-Textbooks.

Science.gov (United States)

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Standard XIV-Textbooks. 36.41 Section 36.41 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR EDUCATION MINIMUM ACADEMIC STANDARDS FOR THE BASIC EDUCATION OF INDIAN CHILDREN AND NATIONAL CRITERIA FOR DORMITORY SITUATIONS Instructional Support § 36.41 Standard XIV—Textbooks. (a) Each school shal...

Nursing textbooks need to inform about spirituality.

Science.gov (United States)

2016-09-21

Considering the spiritual needs of patients is an important aspect of holistic patient care. However, many nurses lack knowledge and awareness of the subject, and spirituality is not strongly featured as a key part of holistic care in core nursing textbooks. The author argues that guidance given by nursing textbooks needs to be more applicable to practice.

Quasi-two-dimensional thermoelectricity in SnSe

Science.gov (United States)

Tayari, V.; Senkovskiy, B. V.; Rybkovskiy, D.; Ehlen, N.; Fedorov, A.; Chen, C.-Y.; Avila, J.; Asensio, M.; Perucchi, A.; di Pietro, P.; Yashina, L.; Fakih, I.; Hemsworth, N.; Petrescu, M.; Gervais, G.; Grüneis, A.; Szkopek, T.

2018-01-01

Stannous selenide is a layered semiconductor that is a polar analog of black phosphorus and of great interest as a thermoelectric material. Unusually, hole doped SnSe supports a large Seebeck coefficient at high conductivity, which has not been explained to date. Angle-resolved photoemission spectroscopy, optical reflection spectroscopy, and magnetotransport measurements reveal a multiple-valley valence-band structure and a quasi-two-dimensional dispersion, realizing a Hicks-Dresselhaus thermoelectric contributing to the high Seebeck coefficient at high carrier density. We further demonstrate that the hole accumulation layer in exfoliated SnSe transistors exhibits a field effect mobility of up to 250 cm2/V s at T =1.3 K . SnSe is thus found to be a high-quality quasi-two-dimensional semiconductor ideal for thermoelectric applications.

Acoustic phonon emission by two dimensional plasmons

International Nuclear Information System (INIS)

Mishonov, T.M.

1990-06-01

Acoustic wave emission of the two dimensional plasmons in a semiconductor or superconductor microstructure is investigated by using the phenomenological deformation potential within the jellium model. The plasmons are excited by the external electromagnetic (e.m.) field. The power conversion coefficient of e.m. energy into acoustic wave energy is also estimated. It is shown, the coherent transformation has a sharp resonance at the plasmon frequency of the two dimensional electron gas (2DEG). The incoherent transformation of the e.m. energy is generated by ohmic dissipation of 2DEG. The method proposed for coherent phonon beam generation can be very effective for high mobility 2DEG and for thin superconducting layers if the plasmon frequency ω is smaller than the superconducting gap 2Δ. (author). 21 refs, 1 fig