bluuebunny/crossref_metadata_2025 huggingface dataset:
An Optimal Learning Environment for Rosemary
Authors: Ruiz Nadeen T.
Published: July 2017

This article discusses the special education placement and instruction of language-minority children identified as mildly disabled, personified by “Rosemary,” in the context of a curriculum guide recently developed in California, The Optimal Learning Environment (OLE) Curriculum Guide: A Resource for Teachers of Spanish-Speaking Children in Learning Handicapped Programs. The guide was written in response to the growing number of such children and to the lack of direction given to special educators in meeting the educational needs of this population. The instructional principles in the guide are based on research with language-minority students and on those with learning disabilities. The guide incorporates existing, promising materials and techniques for use with language-minority populations.
Bilingual Special Education and This Special Issue
Authors: Figueroa Richard A. , Fradd Sandra H. , Correa Vivian I.
Published: July 2017

Bilingual special education is a new discipline that has emerged because of the problems faced by linguistic minorities with the conduct of special education. As current research studies indicate, the progress and innovations ushered in by P. L. 94–142 have not been extended to linguistic minorities, particularly Hispanic children. This special issue suggests that the medical-model, reductionistic paradigm underpinning special education is inimical to bilingual pupils. It proposes a paradigm shift and a redefinition of bilingual special education.
Prereferral Intervention: A Prescriptive Approach
Authors: Fuchs Douglas , Fuchs Lynn S. , Bahr Michael W. , Fernstrom Pamela , Stecker Pamela M.
Published: July 2017

This investigation assessed effects of three increasingly inclusive versions of the Behavioral Consultation (BC) model on problem behavior of students in mainstream classrooms in an effort to develop an effective and efficient approach to prereferral intervention. Subjects were 43 general educators, their 43 most difficult-to-teach students (without disabilities), and 12 school consultants, representing seven inner-city middle schools. Teachers and students were assigned to three BC groups, representing least (BC 1), more (BC 2), and most (BC 3) inclusive variants of BC, and one control group. Preintervention, postintervention, and follow-up observations of student behavior indicated that more inclusive BC versions exerted stronger effects than the least inclusive variant in reducing problem behavior. Theoretical and practical implications for consultation-related activity are discussed.
Nonaversive Treatment of High-Rate Disruption: Child and Provider Effects
Authors: Friman Patrick C.
Published: July 2017

A multiple baseline across three providers showed that each provider, using only differential reinforcement of incompatible behavior (DRI), substantially reduced high-rate out-of-seat behavior in a highly disruptive 4-year-old boy with severe disabilities. During the experiment, duration of the boy's in-seat behavior expanded from less than 1 min to 20 min. Furthermore, during the intervention, the providers' use of physical restraint decreased to near-zero levels, even though restraint and DRI could he used together. Although not specifically targeted, the boy's appropriate toy play also increased during DRI.
Simulated and In Situ Vocational Social Skills Training for Youths with Learning Disabilities
Authors: Clement-Heist Kim , Siegel Shepherd , Gaylord-Ross Robert
Published: July 2017

Social skills training for youth with learning disabilities in transition from school to work is of substantial importance. To examine the generalization of such training to real employment settings, this study used a multiple-baseline design to investigate the effects of 12 measured behaviors (3 behaviors per student) on four high school seniors. An initial simulated social skills package delivered at school led to generalization in 8 of 12 behaviors. Subsequently, in situ training at the work site produced generalization in 4 of 6 behaviors. This two-phase model appears to be a powerful way to promote generalization of behavioral skills.
The Identification of High-School Dropouts Identified as Learning Disabled: Evaluating the Utility of a Discriminant Analysis Function
Authors: Kortering Larry , Haring Norris , Klockars Alan
Published: July 2017

This study examined the utility of a linear discriminant function to distinguish between students identified as learning disabled (LD) who had either been released from high school under codes suggestive of school dropout ( n = 213) or graduation ( n = 92). The discriminant function was comprised of six variables—student ethnicity, reading ability, family intactness, family socioeconomic status, school transfers, and school-initiated interruptions. The analysis determined that differences between the LD dropout sample and LD graduate sample were sufficient to allow for a discrimination between the groups. On the basis of group differences the discriminant function that was constructed correctly classified 83% of the school dropouts and 46% of the school graduates, for an overall 73% accuracy rate. Those factors contributing most to the function were the number of district-initiated interruptions, school transfers, and family intactness. Based on the findings, implications for school districts and future research are noted.
Falling through the Cracks: Rehabilitation Services for Adults with Learning Disabilities
Authors: Smith Judith Osgood
Published: July 2017

The present study investigated the knowledge and perceptions of vocational rehabilitation (VR) of adults with learning disabilities (LD), as well as control variables which describe adults with LD and may have a bearing on access to VR services. This was accomplished by (1) determining the knowledge adults with LD had of their rights under federal rehabilitation regulations; (2) examining demographic control variables (e.g., sex, age, education level, hometown population, employment history, and income), which may have a bearing on the need for or access to VR services by adults with LD; and (3) examining experiences/perceptions of adults with LD regarding the VR application/eligibility process. A pretested questionnaire appeared in the January 1989 ACLD Newsbriefs. Findings indicate that while there was a group of respondents who were satisfied with the rehabilitation services they had received, there was also a large group of respondents who were either ineligible for rehabilitation services or dissatisfied with services they received. Generally, respondents' knowledge of VR was limited.
Grading Secondary Vocational Education Students with Disabilities: A National Perspective
Authors: Rojewski Jay W. , Pollard Richard R. , Meers Gary D.
Published: July 2017

A nationwide purposive sample of secondary vocational educators completed a questionnaire that examined practices and perceptions toward grading students with disabilities. A variety of grading methods was reportedly used, but over two-thirds of respondents included a competency-based grading component. An overwhelming majority believed that student effort should be used to determine grades. Two-thirds of vocational educators had never been involved in their students' IEP development. The most common changes teachers have made over time in their grading practices included becoming more flexible and individualized in grading. Overall, teachers displayed moderately positive attitudes toward grading students with disabilities.
The Perceived Environment of Special Education Classrooms for Adolescents: A Revision of the Classroom Environment Scale
Authors: Trickett Edison J. , Leone Peter E. , Fink Carolyn Molden , Braaten Sheldon L.
Published: July 2017

The Classroom Environment Scale (CES), originally developed for use in traditional public school classrooms, was revised for use in special education classrooms. The scale, which assesses students' perceptions of various aspects of the classroom, was administered to students in 79 special education classrooms in 16 residential and day treatment schools serving special education students with behavior disorders and emotional disturbance. Psychometric analyses showed that only seven of the nine aspects of the classroom found in the original CES were reliably reported in special education classrooms. The revised scale was found reliable for use in special education classes in residential and day treatment settings.
Adjustments to Traditional Procedures for Identifying Underserved Students: Successes and Failures
Authors: Hunsaker Scott L.
Published: July 2017

Thirty-nine school districts were surveyed in a study to examine the success or failure of alternative strategies for identifying gifted students in school districts serving large numbers of culturally diverse students. Many districts listed ethnic/linguistic minorities and economically disadvantaged students as important underserved populations. Alternative identification procedures were primarily intended to expand the assessment basis. Factors most associated with success of procedures included school personnel and assessment practices. Factors causing problems included testing and policies at state and local levels, as well as a lack of recognition of giftedness as it is manifested in diverse cultural populations.
General Education Teacher Planning: What Can Students with Learning Disabilities Expect?
Authors: Schumm Jeanne Shay , Vaughn Sharon , Haager Diane , McDowell Judith , Rothlein Liz , Saumell Linda
Published: July 2017

This in-depth study addressed the nature of general education teachers' planning for content area instruction for students with learning disabilities. Participants included 12 teachers, elementary through high school. Through interviews, classroom observations, teacher reflections, and surveys, we used the Flow of the Planning Process Model to investigate teachers' preplanning, interactive planning, and postplanning activities. Elementary general education teachers did more planning to include the needs of diverse students—and collaborated more with special education teachers—than did teachers at other levels. Other results indicated the extent of special help offered by teachers, as well as the pressures felt by teachers to cover the curriculum.
Practice and Research in Special Education
Authors: Malouf David B. , Schiller Ellen P.
Published: July 2017

This article considers possible reasons that research knowledge is not used more extensively in special education practice and suggests issues to be addressed in solving this problem. We contrast research knowledge and practice knowledge and describe factors that moderate the influence of research on practice, in both general and special education. These factors include teacher knowledge and learning, teacher attitudes and beliefs, and context. We conclude by considering various issues and alternatives for reconceptualizing the relationship between research and practice in special education.
Close to the Classroom is Close to the Bone: Coaching as a Means to Translate Research into Classroom Practice
Authors: Gersten Russell , Morvant Martha , Brengelman Susan
Published: July 2017

This study explored the use of coaching as a way to bring research-based teaching practices into general education classrooms to improve the quality of reading instruction provided to students with learning disabilities. Project staff trained and mentored district special educators on the process of coaching. Qualitative research methodology was used to analyze the process of expert consultation and to better understand the process of change. Key issues that emerged included differences in the ways that special and general educators conceptualize teaching, the differing concerns and priorities between special and general educators, and the anxieties inherent in an observation and feedback process.
Word Problem-Solving by Students with and without Mild Disabilities
Authors: Parmar Rene S. , Cawley John F. , Frazita Richard R.
Published: July 2017

Performance on mathematics word problems having varying structures was compared for Grade 3–8 students with and without mild disabilities. Students with disabilities performed at significantly lower levels than did those without disabilities in four types of word problems, even when the problems involved only single-digit computation. Significant effects were also evident for grade and operation (addition, subtraction, multiplication, and division). The findings highlight the need for math instruction to move from a focus on computation to problem-solving activities, including word problems of varying structures. Further, test developers must make more effort to present a variety of reasoning and problem-solving activities in standardized tests.
Social Behaviors of Children with Visual Impairments Enrolled in Preschool Programs
Authors: Crocker Alison D. , Orr R. Robert
Published: July 2017

This study investigated the social behaviors of children with visual impairments enrolled in a variety of preschool programs. Using the Behaviour Observation Record, the researchers made comparisons between the social interactions of 9 children with visual impairments and a matched comparison group of 9 children with full sight. Observational data indicated that the children with visual impairments were capable of interacting with others. Differences were noted, however, in the frequency of social initiations and the targets of these initiations made by the children with visual impairments. These observations are interpreted in support of the integration of preschool children with visual impairments into general education programs.
Predictors of Victimization Experiences of Adolescents with Disabilities in Transition
Authors: Doren Bonnie , Bullis Michael , Benz Michael. R.
Published: July 2017

This study explored predictors of victimization experiences on a sample of adolescents with disabilities while in school and 1 year after leaving school, through phone interviews of students and parents. Logistic regression analyses revealed that people with serious emotional disturbance who demonstrated low personal/social achievement skills were more likely to experience victimization sometime in their school career than were people with other disabilities and higher personal/social skills. Variables affecting victimization rates 1 year out of school included prior victimization (while in school), gender (females were more likely to be victimized), and arrest record of people with serious emotional disturbance after leaving school.
Teacher Perceptions of Mainstreaming/Inclusion, 1958–1995: A Research Synthesis
Authors: Scruggs Thomas E. , Mastropieri Margo A.
Published: July 2017

Twenty-eight investigations were identified in which general education teachers were surveyed regarding their perceptions of including students with disabilities in their classes. Research synthesis procedures were employed to summarize responses and examine the consistency of responses across time, geographical location, and item type. Overall, we found that about two thirds of general classroom teachers supported the concept of mainstreaming/inclusion. A smaller majority were willing to include students with disabilities in their own classes, but responses appeared to vary according to disabling condition and implicit obligations on the teacher. Although about half or more of the teachers felt that mainstreaming/inclusion could provide some benefits, only one third or less of teachers believed they had sufficient time, skills, training or resources necessary for mainstreaming/inclusion. Reported attitudes did not appear to covary with either geographical region or time of publication. Implications for policy and practice are provided.
Exploring the Technical Adequacy of Curriculum-Based Measurement in Reading for Children Who Use Manually Coded English
Authors: Allinder Rose M. , Eccarius Malinda A.
Published: July 2017

We explored the validity and reliability of curriculum-based measurement reading procedures for progress monitoring purposes with students who are deaf or hard of hearing and who use manually coded English. Results indicate that interjudge and alternative form reliability was very acceptable. However, Pearson product moment correlations between the curriculum-based measurement procedures (e.g., reading passages via signing, identifying idea units, and words retold) and a standardized reading test that was normed with students who were deaf or hard of hearing were lower than expected. Implications for using curriculum-based measurement with students who are deaf and hard of hearing and for assessment of these students are discussed.
An Analysis of Judicial Outcomes of Special Education Cases
Authors: Newcomer James R. , Zirkel Perry A.
Published: July 2017

Special education disputes continue to be a daily concern for public school administrators, a source of anxiety for parents, and a growth industry for attorneys. The filing of a civil suit acknowledges a failure to resolve disputes in local and state administrative forums. To proceed to court represents a significant step in terms of public and parental resources and relationships. Tracking a sample of court cases through the administrative and judicial venues, this study recorded wins and losses at each level in relation to various factors, including the deference accorded by judges to the earlier administrative proceedings. While district wins exceeded parent wins in due process hearings and appeals, the margin narrowed through litigation. The most predominant issue in dispute was placement in terms of parents seeking more restrictive settings. Although ambiguous, the Supreme Court's language in Board of Education v. Rowley (458 U.S. 176, 1982) concerning deference guided court outcomes. Success rates provide useful insights to parents and school districts as they address the special education question at the end of administrative hearings: to court or not to court.
An Electro-Mechanical Teaching Model for The Transistor
Authors: Nair Achuthsankar S.
Published: July 2017

An electro-mechanical teaching model for the transistor

An electro-mechanical teaching model for introducing transistor action to engineering students, especially non-electrical engineering students, is presented here. When this model is utilised, absolutely no mention need be made of electrons or holes even to introduce complex concepts.
The Root Loci Equation and Its Application
Authors: Filanovsky I. M.
Published: July 2017

The root loci equation and its application

The general algebraic equation of root loci is derived. Application of this equation to some problems of electronics and control can simplify calculations.
New Undergraduate Laboratory Experiments on Induction Generators
Authors: Banerjee Soumitro
Published: July 2017

New undergraduate laboratory experiments on induction generators

With the increased importance of induction generators in energy conversion from nonconventional sources, it has become necessary to cover this subject extensively at the undergraduate level and offer experiments on it. This paper presents a few undergraduate experiments on induction generators developed at I.I.T. Kharagpur, India.
A Programmable Load Bank for Machine Laboratories
Authors: Lawrance W. B. , Aitken C.
Published: July 2017

A programmable load bank for machine laboratories

This article describes the design and construction of an 8 kW, programmable, resistive load bank suitable for a variety of applications in electrical power laboratories.
Analysis of Self-Excited Induction Generators Using Symbolic Programming
Authors: Chan T. F.
Published: July 2017

Analysis of self-excited induction generators using symbolic programming

Using the symbolic programming language MACSYMA, the self-excited induction generator may be analysed in a straightforward manner with a high degree of accuracy. Very little manual effort need be spent on algebraic manipulation, numerical analysis and computer programming. Typical program sessions are cited to illustrate the elegance of this approach.
Adolescents' Attitudes Towards Electronic Engineering
Authors: Sewell D. F. , Pulko S. H. , Brown Emma
Published: July 2017

Adolescents' attitudes towards electronic engineering

The attitudes of 640 adolescents (aged 16–17) toward Electronic Engineering were surveyed by questionnaire. Students reported a number of negative attitudes in comparison with two other academic disciplines. It is considered that such attitudes originate in childhood and at school and have adverse consequences for recruitment into the subject.
Computer-Controlled Induction Motor Drive for Teaching Purposes
Authors: Gieras J. F. , Buhlmann H. H.
Published: July 2017

Computer-controlled induction motor drive for teaching purposes

A digital-computer-controlled variable-speed drive with 1.5 kW induction motor has been designed. The commercial squirrel cage as well as solid steel rotors have been applied. The load characteristics for speed control (open and closed-loop) have been presented and discussed.
‘People and Systems’: An Exercise in Student Participation
Authors: Carpenter Geoffrey F.
Published: July 2017

‘People and Systems’: an exercise in student participation

When a course is revised and its relevance, quality and effectiveness are reviewed, the role to be played by the students themselves should not be overlooked. This paper argues that a seminar programme where the students themselves have to play an active role in its preparation and presentation provides an effective mechanism for knowledge transfer.
An Expert Systems Course for Students of Electronic Engineering
Authors: Jervis B. W.
Published: July 2017

An expert systems course for students of electronic engineering

An expert systems option taught to final year students of electronic engineering is described. The students are motivated to learn and acquire practical ability by emphasising electronics applications and using a variety of teaching techniques.
Spreadsheet Demonstrations of Discrete and Fast Fourier Transforms
Authors: Chapman David
Published: July 2017

Spreadsheet demonstration of discrete and fast Fourier transforms

The creation of discrete and fast Fourier transforms on a spreadsheet is a simple and informative exercise which graphically illustrates the simplicity and symmetries of the FFT. Experiments with ‘what-if’ exercises on the resulting spreadsheets lead to insight into concepts of the digital time and frequency domains.
A Set of Experiments in Optimal and Predictive Control
Authors: Moreno L. , Acosta L. , Ichaso J. L. , Sánchez J. L. , Piñeiro J. D.
Published: July 2017

A set of experiments in optimal and predictive control

A set of simulation experiments in optimal and predictive control is presented. The paper describes a sequence of eight experiments performed in PASCAL and MATLAB. These experiments have been carried out with the aim of improving the student's understanding of control concepts. A brief discussion of the algorithms and details of each experiment are given.
The Effect That Weighting of Different Stages of a Degree Course has on Degree Classification
Authors: James C. , Hub D. R.
Published: July 2017

The effect that weighting of different stages of a degree course has on degree classification

An investigation is reported on how the degree classifications given to 280 students over a 10-year period would have been changed if the weighting given to various parts of the course were altered. It is found that the percentage overall changes between degree classifications are small, making a difference to about 2 in 100 classifications when the Final Year weight is changed by 10%.
Final Year Project as an Important Component of the Electrical and Electronic Engineering Degree Course at the University of Greenwich
Authors: Vaezi-Nejad S. M.
Published: July 2017

Final-year project as an important component of the Electrical and Electronic Engineering degree course at the University of Greenwich

This paper describes the aims, structure, organisation and assessment of the projects offered to our final year student doing the B. Eng. degree course in Electrical and Electronic Engineering. The criteria for project progression and some recent projects are also described.
Method of Circuit Analysis Based on Relaxation of Kirchhoff's Laws and the Cauchy-Riemann Conditions
Authors: Moreno E. , Ares F. , Estévez H.
Published: July 2017

Method of circuit analysis based on relaxation of Kirchhoff's laws and the Cauchy–Riemann conditions

A new method has been developed for analysing electrical circuits which leads to a set of general formulae for the electrical parameters. These equations involve elementary calculations. A numerical example is given to illustrate the speed of the method.
An Analytical Tool for Studying Transformer Inrush Current
Authors: Chakravarthy S. K. , Vasu E. , Nayar C. V.
Published: July 2017

An analytical tool for studying transformer inrush current

An analytical tool for studying transformer inrush current is proposed. The existing approaches dwell at length in solving differential equations which do not provide any insight into the parameters that affect inrush current. A block diagram form of representing the transformer has been proposed and verified based on typical transformer data.
Development of Expert System Course for Electronic Engineering Students
Authors: Jain L. C. , Bowden B. S.
Published: July 2017

Development of an Expert Systems course for electronics students

In 1986, ‘Expert Systems’ was first offered to Computing and Information Systems students. Over time, Business, Management, and Engineering students elected to take this subject. In 1991, ‘Electronic Design with Expert Systems’ was specifically created for Electronic Engineering students. The evolution of both subjects and the lessons learned are discussed.
Artificial Intelligence Languages in Engineering Education
Authors: Rowland J. G. , Jain L. C.
Published: July 2017

Artificial intelligence languages in engineering education

This paper looks at the two most commonly used artificial intelligence programming languages, LISP and PROLOG. The differences between conventional programming and symbolic computing and between LISP and PROLOG are presented. Some comparisons between code in PASCAL, LISP and PROLOG are given.
Circuit Analogy to Introduce Variational Methods
Authors: Gibson Andrew A. P.
Published: July 2017

Circuit analogy to introduce variational methods

Variational procedures, energy expressions and the minimum energy principle are often difficult steps to introduce in advanced undergraduate and postgraduate courses in Electrical Engineering. A simple preamble, relying only on a basic circuit analogy, can be used to overcome these difficulties and is presented here.
Symbolic Circuit Analysis Using Mathematica
Authors: Teng Jianfu , Fidler J. K. , Sun Yichuang
Published: July 2017

Symbolic circuit analysis using Mathematics

A method of symbolic circuit analysis using Mathematica is reported. With the powerful symbolic manipulation capacity of Mathematica, symbolic circuit analysis is significantly simplified. The analysed circuits can be passive or active, with active devices modelled by nullors. Non-trivial circuit analysis examples are presented and the program list is given.
Behavioral Simulation of an Arithmetic Unit Using The Spreadsheet
Authors: Levin Ilya
Published: July 2017

Behavioral simulation and arithmetic unit using the spreadsheet

This paper examines the use of spreadsheets for the construction of the behavioral simulation of Arithmetic Units. It is shown that the spreadsheet is appropriate both for teaching and learning of different types of Arithmetic Units. These units can be simulated very simply by students during the lesson.
Control of the Double Integrator Process: A Cautionary Tale in Discretization
Authors: Paor Annraoi De
Published: July 2017

Control of the double integrator process: a cautionary tale in discretization

Starting with a double integrator under analog PID control, various discretization options are explored using Program CC. Asymptotic stability is achieved in only three cases out of seven. The failures are explained. The analog controller is then redesigned by applying a lowpass filter to the derivative term, and asymptotic stability results in all seven cases, though with inferior dynamics in one.
The Internet — A First Year Course Option for an Engineering Common Programme
Authors: Harris R. G.
Published: July 2017

The Internet — a first year course option for an engineering common programme

For new users of the Internet there is a need for a coherent presentation of its facilities. A first year option for all engineering students at Sheffield Hallam University is ‘Navigating the Information Super Highway’ which achieves this. The paper outlines the rationale of this course, describes the topics covered, course structure and student response to it.
Using Computer Simulation as a Bridge Between the Classroom and Laboratory
Authors: Darnell John , Stern Harold P.
Published: July 2017

Using computer simulation as a bridge between the classroom and laboratory

This paper discusses the use of computer simulation as a bridge to create a smooth transition between classroom material and laboratory exercises in combined lecture-lab courses. Such bridging increases students’ capability to validate laboratory results, resolve problems, and correlate classroom and laboratory materials. Results of student surveys are given.
Novel Technique for Automatic Measurement of the Frequency Characteristics of Linear Systems
Authors: Abuelma'atti Muhammad Taher
Published: July 2017

Novel technique for automatic measurement of the frequency characteristics of linear systems

A method is described for measuring and calculating the phase angle and magnitude of the harmonics corresponding to a periodic signal. The implementation of this method requires only simple basic mathematical operations and can be easily implemented in microcomputer- or microprocessor-based real-time systems. The proposed method can be easily used for measuring the frequency characteristics of linear systems.
A Graphics Simulation Environment for Power System Education
Authors: Gooi H. B. , Zhu S. P.
Published: July 2017

A graphics simulation environment for power system education

This paper describes a LAN-based system for load flow simulation studies. The system comprises an automatic one-line generator, a graphical user interface (GUI), print and database supporting tools. One-line displays can be generated either manually or automatically. The GUI was designed using the object-oriented programming (OOP) paradigm.
Ampere and Faraday: The Electromagnetic Symmetry
Authors: Rajaraman K. C.
Published: July 2017

Ampere and Faraday: the electromagnetic symmetry

Emf induced by flux-cutting is interpreted as that in a closed circuit due to an enclosed ‘magnetic (convection) current’. Conversely, the m.m.f. in a closed magnetic circuit enclosing a current is interpreted as due to cutting of electric flux. These interpretations make the picture of electromagnetic phenomena complete and symmetrical.
Interfacing a Weather Station Data Logger to a Laboratory Microcomputer
Authors: Wilson David , Ohlbach Les , Fulcher John
Published: July 2017

Interfacing a weather station data logger to a laboratory microcomputer

This paper discusses the hardware and software design aspects of interfacing a MC68000-based laboratory microcomputer to a custom weather station data logger, capable of logging temperature, humidity, air pressure, wind speed and direction. The software system comprises a data logger running in background mode, together with a Graphical User Interface.
Root Locus Diagrams and the Effect of Zeros on System Response
Authors: Jones J. C. Peyton , Atherton D. P.
Published: July 2017

New expressions, and a graphical notation are introduced to quantify the effect of zeros on step response characteristics. The expressions, which also hold for non-minimum phase systems, are illustrated geometrically in the s-plane, and give a more accurate insight into a concept of pole dominance than the standard ‘pure-pole’ approximations.
Developing a Conceptual Base for Undergraduate Communications Courses
Authors: Stern Harold P. , Salem Thomas E.
Published: July 2017

This paper develops a conceptual base for undergraduate communications courses which enhances learning, improves motivation, provides a format for suggesting practical applications, constructs a framework for design and analysis, and illustrates correlation with other engineering subjects. Examples apply the conceptual base to specific topics, and student evaluations illustrate its effectiveness.
Design of Low-Pass Active Filters Using Matlab
Authors: Joaquim Marcelo Basilio
Published: July 2017

In this paper a program developed in MATLAB programming language to aid in the design of all-pole active filters using operational amplifiers is presented. The filter structure chosen was the Sallen-Key that furnishes a filter with low sensitivity to element tolerances and it is easy to implement in hardware.
Conceptual Difficulties in the Teaching of The Photodetection Process
Authors: Fraile-Peláez F. Javier , Chamorro-Posada Pedro
Published: July 2017

We identify and address the most deficiently understood aspects of photodetection techniques. Didactical arguments are used to facilitate the comprehension of the nature of the signal noise. Intuitive predictions are used to shed light on the mathematical results, the physical meaning of which is often not well understood.
Use of The Analytic Method and Computer Algebra to Plot Root Loci
Authors: Cogan Brian
Published: July 2017

The analytic method for plotting root loci is examined. The basic equation for this method, originally published by Bendrikov and Teodorchik4 in 1959, is derived in a very simple way. A second equation, which complements the original Bendrikov equation, is also derived. An example of how these two equations may be used to plot root loci using Mathematica is presented.
Relationship of k-factor versus Density for Various Appliance Foam Formulations Containing Next Generation Blowing Agents
Authors: King J. A. , Latham D. D. , Ackley J. C.
Published: July 2017

With the eminent elimination of CFC-11 (trichlorofluoromethane) as a blowing agent in rigid polyurethane foams, a greater understanding of the effect of the new alternative blowing agents on foam physical properties is needed. This is especially true in the appliance industry, where k-factor is of supreme importance to the overall energy consumption. Stringent energy requirements, along with the market pressures to continually lower the density of the foam, gives added challenges to new system development. This paper addresses the critical balance between k-factor and density, or cell gas content. Since the thermal conductivity of the gas plays the major role in the overall k-factor equation, it could be theorized that the addition of more blowing agent should lower the overall k-factor of the foam. However, a point exists at which the addition of blowing agent is actually detrimental to the overall k-factor, and lower gas levels can actually improve the insulation properties. This point is largely controlled by the amount of gas trapped within the cell, which directly affects the density and cell size of the foam. When too much gas is trapped within the cells during their formation, the cells will expand due to higher internal pressures, thus increasing the cell size and radiative contribution to k-factor. There will be an optimal level of gas contained within the cells to achieve the lowest k-factor for any given foam formulation. To address this issue, several foam formulations containing various alternate blowing agents were studied.

Systems studied include TDI and MDI based formulations, blown with HCFC-141b (1,1-dichloro-1-fluoroethane) along with two MDI based systems; one blown with HFC-134a (1,1,1,2-tetrafluoroethane) and the other with cyclopentane. All foams were co-blown with various amounts of carbon dioxide generated from the water/isocyanate reaction. After the basic components for the foam formulations were determined for each of the blowing agents studied, a systematic approach was used to vary the cell gas level in each formulation. A graphical representation of k-factor versus cell gas level was generated for each system along with other physical properties. Based on this information, a better understanding of the effects of density on k-factor for the next generation of blowing agents can be obtained.
Comparison of the Factorial Structure of Oral Coding Patterns for a Middle-Class and a Working-Class Group
Authors: Poole Millicent E.
Published: July 2017

The present study was designed to compare the factorial structure of oral coding patterns for a middle-class and a working-class group in terms of a Bernstein derived thesis of greater differentiation and specificity for middle-class subjects because of their ability to manipulate more of the semantic and structural resources of language. Twenty-eight indices of oral coding elaboration were obtained from 40 middle-class and 40 working-class tertiary students. Pearson Product-Moment correlations were obtained and, by using principal components factor analysis, the middle-class matrix yielded nine factors, the working-class matrix eight. By interpretation of the factor patterns and statistical comparisons using Burt's coefficient of congruence, the thesis of greater differentiation and specificity in middle-class code elaboration was sustained.
The Acceptability of Linguistic Connectives as a Function of the Relationship Between the Referent Events
Authors: Sullivan Laraine
Published: July 2017

An investigation of the effects of experiential and linguistic variables on the preference for within sentence connectives. 8 items were constructed, each consisting of 2 clauses describing sequential events which varied in the perceived frequency of relationship and perceived temporal order (determined by subject ratings). There were 4 conditions: the clause order was either congruent with the perceived temporal order (A-B order) or opposite to it (B-A order), and the clauses were either in the Past or the Present Tense. Subjects in each condition (n = 13) ranked connectives in order of preference for each item. Results showed that frequency of relationship between described events was most likely to be a determining factor in connective preference when the clauses were in the A-B order or they were in the Past Tense. These results were substantiated by an independent absolute judgment procedure in which each sentence was rated for acceptability. Different groups (n = 29) rated the sentences in the A-B order and the B-A order. Generally the results were in agreement with the preference task, although an adaption level effect was apparent in the judgments. These results are discussed in terms of the degrees of freedom of interpretation allowed by the various linguistic connectives.
Sign Recognition Processes in American Sign Language: the Effect of Context
Authors: Clark Lorene E. , Grosjean François
Published: July 2017

The effect of context on sign-recognition processes in American Sign Language (ASL) was studied by means of the gating paradigm (Grosjean, 1980). Individual signs were presented in two different conditions: a context condition in which signs were preceded by a context, and a no-context condition in which they were excised from the signing stream. A strong context effect was found: signs were isolated sooner in context, perfect confidence in the response was reached earlier, and the candidates proposed before the isolation point reflected a narrowing-in process that was both semantic and phonological. Future research in sign recognition and models of lexical access are discussed in light of these findings.
Electrophysiological Studies of Visual Word Perception, Lexical Organization, and Semantic Processing: A Tutorial Review
Authors: Bentin Shlomo
Published: July 2017

Visual word recognition requires the matching of an orthographic unit to its meaning via a phonological unit in the mental lexicon. The nature and the speed of this process are affected by “bottom-up” factors (e.g., the manner in which the phonology is represented by the orthography) and by “top-down” factors (e.g., network connections between related words in the lexicon, and contextual semantic information). Event-related potentials (ERPs) provide a relatively new tool that complements behavioral measures of word recognition. ERP components recorded during word perception tasks have been found to be sensitive to orthographic, phonological, and semantic manipulations. They go beyond behavioral measures by providing continuous information about the activity of the cognitive system from stimulus onset to the occurrence of the response. in addition, ERPs enable the researcher to examine word perception and reading in more natural situations, without time constraints and overt responses. Finally, intra-cranial ERP recording in humans and modern analytical techniques may shed light on the relations between cognitive linguistic processes and brain structures. Collaboration between cognitive psychologists, linguists, and ERP researchers will be necessary to exploit the great potential of these electrophysiological techniques.
Variance Tolerancing and Decomposition in Short-Staple Spinning Processes: Part I: Modeling Spun Yarn Strength Through Intrinsic Components
Authors: Koo Hyun-Jin , Suh Moon W. , Woo Jae L.
Published: July 2017

A variance tolerancing method is developed as a means for separating and estimating random errors associated with raw materials and yarn structures from process-induced errors based on structural relationships governing the strength of a spun yarn. The method is successfully used to estimate the mean and variance of spun yarn strength by propagating the statistical parameters of fiber properties onto those of the resulting spun yarns. In developing the new estimation procedure, probabilistic models based on the distributions of fiber length and tensile properties are combined with geometric and structural models of fiber arrangements in spun yarns. For the first time, the concept of “effective gauge length” is used to model and simulate the breakage process of spun yarns. The new concept and specific methodology are aimed at better controlling process and product characteristics by quantifying the variances according to their sources.
Photodegradation of Lyocell Fibers Through Exposure to Simulated Sunlight
Authors: Dadashian F. , Wilding M. A.
Published: July 2017

This research investigates changes occurring in lyocell fibers resulting from exposure to simulated sunlight, FTIR microspectroscopy is used in combination with measurements of tensile properties, fluidity, moisture regain, yellowness, weight loss, and birefringence. X-ray diffraction and SEM are used to determine crystallinity and fiber surface changes, respectively. The results indicate no significant changes in physical properties up to 96 hours' exposure. At 168 hours, open pores appear on the fiber surface, probably due to the release of gaseous products, accompanied by an increase in moisture regain.
Peroxynitrite as a Novel Stain Bleaching Reagent
Authors: Madison Stephen A. , McCallum Jeremy E. B. , Wahl Roy U. Rojas
Published: July 2017

Peroxynitrite serves as an effective stain bleaching reagent. Tests with several stained cotton fabrics show the potential commercial application for this biologically interesting molecule in fabric washing systems.
Structural Characterization of Wool by Thermal Mechanical Analysis of Yarns
Authors: Cao Jinan , Bhoyro Ahmed Y.
Published: July 2017

A thermomechanical analysis of yarns in a tensile mode is used to characterize wool fibers modified to show the β-crystal form in comparison with native untreated wool retaining the α-crystal form. The TMA curves show that fiber extension causes significant structural modification of the wool samples. In particular, melting of the α-form crystallites in native wool can be detected at around 215°C, with supercontraction prior to effective crystallite melting. But extended wool yarn shows no thermal mechanical event corresponding to melting of the β-form crystallites. Extended wool has a thermal mechanical behavior similar to that of silk yarn.
Effect of Light and Heat on Color and Deterioration of Viscose, Acetate, and Cuprammonium Fabrics
Authors: Fletcher Hazel , Houston Miriam H.
Published: July 2017

Light decreased the breaking strength of the viscose, acetate and cuprammonium rayons uniformly. Heat decreased the break ing strength of all of them considerably, but the cellulose acetate rayons were more resistant to heat than the other two kinds. Light produced little change and heat much change in color. The cellu lose acetate rayon fabrics were affected the least. The ash alka linity showed no perceptible increase or decrease for any of the rayons exposed to light or heat. The amount of increase in the copper number and per cent solubility in sodium hydroxide was ap proximately the same for the viscose and cuprammonium rayon fabrics, and it was less in the case of the cellulose acetate rayon fab rics. Thus the greater change in breaking strength, copper number and per cent solubility in sodium hydroxide indicates that the viscose and cuprammonium rayon fabrics were deteriorated more by heat than the cellulose acetate rayon fabrics.
Factors Influencing Flocculation and Precipitation. Theory and Variables
Authors: Beavers E.M. , Magoffin J.E. , Cameron F.K.
Published: July 2017

Flocculation and precipitation of a colloidal dispersion are insep arably related in as much as the phenomena associated with the latter process are closely dependent upon those of the first. This paper will offer a brief discussion of the information relevant to both these processes, and of the variables to be encountered in such an investigation. Reports to follow will present the results of experimental work.
Durable-Press Cotton by Wet Fixation
Authors: Colbran R. L. , Corless M. G. , Maitland C. C.
Published: July 2017

Evidence is presented showing that only a very small proportion of dihydroxydimethylol cyclic ethylene urea (DHDMEU) is fixed when a bath containing equal amounts of melamine-formaldehyde (MF) and DHDMEU precondensate solids at a pH of 2 is used in wet fixation. The presence of DHDMEU also suppresses fixation of the MF component. Under more acid conditions, where more efficient fixation of DHDMEU occurs, so that high smoothness and wrinkle recovery are obtained with either or both components, DHDMEU gives the lowest and MF the highest strength and abrasion resistance, with mixtures giving intermediate results.

Several MF precondensates of differing constitution have been compared in wet fixation by the continuous steaming and the cold batch procedures. In both cases, it was essential to maintain a high formaldehyde/melamine ratio on the fabric during the wet cure stage, so as to ensure adequate cross-linking in the final cure.

A novel method of wet fixation, involving passage of the impregnated fabric through a hot oil bath is described.
Drug-crime Relations among Drug-Consuming Juvenile Delinquents: A Tripartite Model and More
Authors: Brunelle Natacha , Brochu Serge , Cousineau Marie-Marthe
Published: July 2017

From a phenomenological perceptual stance, we aim, in this article at revealing youths' own personal perceptions regarding the drug-crime nexus in their trajectories. Within a qualitative research approach, autobiographical accounts were used with 38 young drug users and delinquents between 16 and 18 years old (22 boys and 16 girls). With the reference point of this article being Goldstein's (1985) tripartite drug-crime model, our results show support for parts of this model as well as nuances to it. Also, another type of drug-crime nexus emerged from these accounts. More specifically, a “psychopharmacological” and a “monetary” drug-crime link were described by youths, and an absent or intermediary relation too. Goldstein's systemic model did not merge in this study. Personal feelings, meanings and logic of youths permit us to elaborate on and further qualify these drug-crime nexuses in the trajectories of young drug users and delinquents.