bluuebunny/crossref_metadata_2025 huggingface dataset:
Reaction of Cystine Residues in Wool with Peroxy Compounds
Authors: Douthwaite F.J. , Lewis D.M. , Schumacher-Hamedat U.
Published: March 2008

Wool was oxidized under aqueous acidic conditions with Caro's salt, and the oxi dation products of cystine were measured using Fourier transform infrared spectroscopy coupled with the attenuated total internal reflectance sampling technique. The reso lution of the infrared bands in the wool spectrum was improved by differentiation to the second-order derivative. Following differentiation, individual sulphur-oxygen bands in the infrared spectrum of wool were resolved and identified. The intensity of the cysteic acid band was proportional to cysteic acid concentration, and following such oxidation treatments of the wool substrate, cysteic acid was the main oxidation product formed from cystine. The overall effect of applying Caro's salt to wool was determined by high performance liquid chromatography. The amino acids were labeled with the fluorescent tag, 9-fluorenylmethyl-chloroformate, separated on a C-18 column, and detected at 340 nm. The results show that permonosulphuric acid treatments convert cystine to cysteic acid and methionine to methionine sulphoxide and reduce the con centration of tyrosine in wool.
A New Method for Measuring Carpet Texture Change
Authors: Wang J. , Wood E.J.
Published: March 2008

Texture change (or retention) is an important aspect of a carpet's performance in use. Objective measurement of texture change using image analysis has become a useful tool for assessing the textural quality of carpets. This paper discusses a new approach to measuring changes in carpet texture by analyzing the Fourier power spectra of the images of control (unworn) and worn carpets. Through a series of steps involving analysis of the intensity profile of a carpet image using template matching, pre-processing by high-pass filtering, and reduction to a one-dimensional spectrum by taking the rotationally averaged power spectrum of the carpet image, a feature can be extracted that represents the pile texture change. The algorithm has been tested experimentally using a range of carpet types, including those that have been difficult to measure reliably with other image analysis algorithms. The new measure agrees well with the subjective impression of tuft texture change and wear, and excellent discrimination between different levels of wear has been achieved in all cases.
Spectral Analysis of the Stick-Slip Motion of Dynamic Friction in the Fabric Surface
Authors: Hosseini Ravandi S.A. , Toriumi K. , Matsumoto Y.
Published: March 2008

We have studied the influence of fabric structure on the stick-slip motion of dynamic frictional force. Autospectral density function analysis demonstrates that the nature of stick-slip motion is periodic and depends on fabric construction. Warp, weft density, and yam irregularity affect stick-slip data and can be objectively measured using an automated apparatus for plain woven cotton fabric. One observation is that the stick- slip motion also depends on lateral shifting, where the yams protruding from the body of the fabric are repeatedly stretched and released during sliding of a sled under normal load on the fabric surface. We have investigated the effects of fabric structure on stick- slip motion as a function of weft density using perspex-over-fabric friction.
Theory and Practice of Cotton Fiber Selection
Authors: El Mogahzy Yehia E. , Gowayed Yasser
Published: March 2008

The cotton mixture as a multi-component blend of inherently variable natural fibers imposes several challenges with regard to the proper method of selecting fibers for a uniform blend and consistent output characteristics. Part I introduces a number of fiber selection techniques and based on these techniques, proposes three different bale picking schemes. The first scheme is random picking, which resembles the tra ditional massive blending and serves as the basis for more advanced schemes. The second scheme is proportional weight category picking, in which the distribution of a fiber characteristic is divided into a number of classes, and bales are picked from each class in quantities proportional to class relative frequency. The third scheme is optimum category picking, in which bales are selected on the basis of optimizing factors that contribute to blend uniformity. These factors include category variance, picking cost, and category inventory.
Air Interlaced Yarn Structure and Properties
Authors: Miao Menghe , Soong Mei-Chun Christa
Published: March 2008

The air interlacing technique is used to introduce intermittent nips to a flat filament yam so as to improve its performance in further textile processing. Observation of the interlaced flat yam nips reveals that their structure is very complicated and can be categorized into four classes: twist, braid, wrap, and entanglement nips. The formation of these nip structure classes is largely affected by the condition of filament separation prior to mingling. Interlacing causes deterioration to filament yam mechanical prop erties to various degrees, depending mainly on processing conditions, and the change in yam properties is correlated to nip structure characteristics.
Endotoxin Reduction in Dust from Heated Cotton Fibers
Authors: Rousselle Marie-Alice , Chun David T.W.
Published: March 2008

Cotton was heated in a gas-fired pilot plant dryer at temperatures previously shown to reduce endotoxin levels in fiber. Heating at 255°C for 20 seconds reduced the endotoxin content of dust collected from the fibers by 90% as measured by the Limulus amebocyte lysate assay. However, heat detoxification at 255°C had a detrimental effect on fiber physical properties as evaluated by high volume instrument testing, with a 24% reduction in fiber strength, a 6% reduction in length, and a 7% reduction in uniformity index. Dust release from cotton heated at 255°C was three times that from unheated cotton.
Applying Principal Components Analysis to the Amino Acid Composition of Keratin Materials
Authors: Wortmann F.-J. , Wortmann G. , Zahn H.
Published: March 2008

To characterize keratin materials and assess changes due to processing, amino acid analysis (AAA) is an important tool, yielding a complex data pattern. Principal com ponents analysis is applied to AAA data taken from the literature for a wide variety of keratins from various sources as well as their main protein components. The analysis reveals that the principal components underlying the AAA spectrum mainly relate to the keratin intermediate filaments and their associated proteins on the one hand and the high glycine-tyrosine proteins on the other. Principal components analysis of amino acid analyses can thus be considered a versatile tool with a high potential to detect and assess changes in keratins due to natural or artificial causes.
Measuring the Contact Angles of Liquid Droplets on Wool Fibers and Determining Surface Energy Components
Authors: Le C.V. , Ly N.G. , Stevens M.G.
Published: March 2008

Contact angles of various liquids on wool fibers are measured using the liquid droplet method. A computational technique greatly simplifies contact angle calculations. Sur face energy components of differently treated wool fibers are determined from the contact angle data using current theories of surface energy. Values for the surface energy of wool fibers calculated using the equation of state and the geometric-mean equations show a dependence on the kind of liquid used. Calculations based on the acid-base approach give more consistent results, but for wool fibers with high polar components, reliable results are obtained only with particular liquids. Untreated wool fibers are weak γ- monopoles. Wool fibers set in steam have a higher γ LW and γ+, with the γ - remaining unchanged. Chlorination changes wool fibers to bipolar solids with substantial increases in γ LW,γ+, and γ-.
Analysis of Fiber Finishes Using SFE Coupled to a Simple, Universal IR Flow Cell
Authors: Liescheski Phillip B. , Seemuth Paul D. , Trask Terry O.
Published: March 2008

This paper presents a method for analyzing polyurethane fiber finishes based on supercritical fluid extraction (SFE) coupled directly to an infrared (IR) spectrometer by means of a simple, universal IR flow cell. In this method, supercritical CO2 is used to replace environmentally hazardous perchlorinated solvents. An automated sample- loading SFE extractor reduces analysis labor. Extract effluent from the extractor flows through a heated capillary transfer line and a high-pressure, standard-geometry IR flow cell. The flow cell can be used to couple the SFE extractor with almost any IR spectrometer. The system is tested with a fiber finish analysis method using polyure thane fiber samples, and the data and other fundamental information are presented.
A Simplified Model of Fabric Drape Based on Ring Theory
Authors: Stump D.M. , Fraser W.B.
Published: March 2008

A simplified model of textile fabric drape based on two-dimensional ring theory is applied to the circular geometry of the drapemeter. A material parameter incorporating fabric properties and drape geometry is identified and used to characterize the drape response in terms of the energy contained in a series of deformed rings. Results of the analysis include the prediction of drape configurations and an explanation of their nonuniqueness based on energy content.
Enhancement of Coolness to the Touch by Hygroscopic Fibers
Authors: Li Y. , Holcombe B.V. , De Dear R.
Published: March 2008

Physical mechanisms responsible for subjective differentiation in coolness to the touch between textile fabrics are investigated in terms of the dynamic moisture sorption behavior at the interface between skin and fabric. The change in skin temperature during initial contact with fabric is related to the rate of moisture desorption at the inner surface of the fabric, which in turn directly relates to the sorption capacity and diffusion coefficient of the fibers involved, and to the inverse of the fiber diameter. By applying a model of skin thermoreceptor behavior to the skin temperature response predicted from the moisture sorption behavior of fabrics during skin contact, the integrated thermoreceptor impulse output, known as the psychosensory intensity, can be used to predict subjectively perceived differences in coolness.
Modeling for Suppression of Moisture/Temperature Induced Dimensional Changes in Unbalanced Fibrous Composite Structures with Perfect Bonding
Authors: Yiping Qiu  , Backer Stanley
Published: March 2008

Suppression of dimensional change induced by moisture and temperature changes is studied for perfectly bonded, unbalanced, parallel fibrous structures composed of at least one hygroscopic component, taking into account various parameters such as initial moisture content and temperature at the time of assembly, width or height ratio of the two components. molecular orientation, and bonding length. The results show that two factors play major roles in moisture/temperature induced dimensional (curvature)

change: longitudinal fiber swelling/shortening and material softening/stiffening. Whether the effects of the two factors are additive or compete against each other depends on the initial moisture content and temperature at the time of structural assem bly. When the structure subsequently absorbs moisture, the resulting maximum cur vature decreases as initial moisture regain and initial temperature increase, whereas the opposite is true when the structure desorbs moisture. A higher orientation factor of the hygroscopic component results in a higher maximum curvature. The induced curvature of an unbalanced structure goes through a maximum when the width ratio or height ratio of the two components changes.
Treating Cotton with Cellulases and Pectinases: Effects on Cuticle and Fiber Properties
Authors: Yonghua Li  , Hardin Ian R.
Published: March 2008

Cellulases and pectinases are used to treat raw cotton fibers and unscoured cotton fabrics. The structural changes in the surfaces of cotton caused by the enzymatic treat ments and resulting properties are the main focus of this study. Both staining tests and microscopy observations confirm that the cuticle is removed by the pectinases and cellulases. All evidence of fiber weight loss and fabric water absorbency shows that significant changes in cotton fiber and fabric properties occur with mild treatment conditions. Physical changes in the cotton surfaces are clearly revealed by scanning electron micrographs. All fiber weight loss values stemming from the enzymatic treat ments are smaller than or near the cotton cuticle weight. Sufficient water absorbency for textile processing is obtained with mild enzymatic treatments, corresponding to a small but statistically significant fiber weight loss.
A New Apparatus and Method for Tensile Testing at High Strain Rates
Authors: Freyburger Jean-Marie , Drean Jean-Yves , Madrolle François , Marques Filipa Alexandra , Silva Elisabete Cabeço
Published: March 2008

A high speed dynamometer is developed to measure the mechanical properties of linear textiles at strain rates similar to those encountered in manufacturing processes. Experiments based on 57 tex poly ( ethylene terephtalate ) yams permit us to investigate the influence of some important parameters such as inertia effects, transverse vibrations, clamping type, and sample gauge length on mechanical behavior. The clamping system and gauge length have a pronounced influence on the yam's properties, while the effects of inertia force and transverse vibrations are negligible.
Theoretical Control and Experimental Verification of Carded Web Density
Authors: Kuo Chung-Feng Jeffrey , Liu Chien-Hui
Published: March 2008

A modem control strategy including controller design and system output modifica tion is illuminated by application to feedback control of a carded web control system. Since the carded web system is a type-zero plant, an integrator in the feedforward path between the error comparator and the plant is inserted to improve the system type. A new controllability property is the key in the application of this kind of control system design technique. At the same time, the computer simulation result is proved by theo retical analysis. A performance comparison is made of the conventional controllers versus this modem control scheme, and the performance of the new control strategy is effectively demonstrated by computer simulations.
Headspace Resistance Standards for the Shirley Developments Ltd. Micromat Tester
Authors: Montalvo Joseph G. , Faught Sherman E.
Published: March 2008

High precision headspace resistance standards (HRS) are developed for the Micromat model of the Shirley Developments Ltd. fineness and maturity tester. The Micromat measures cotton fineness and maturity based on the principle of air permeability through a fixed mass of fibers at two different stages of compression. Differential pressures are the quantities measured, and are related to maturity and fineness by appropriate equa tions. HRS are mechanical air flow restrictors: we use narrow diameter tubes, needle valves, and metal frits. Air flow rates through the calibration cotton are adjusted to give the declared differential pressure values, and these flows are exactly "transferred" to the HRS. The calibration transfer coefficient β, defined as the ratio of differential pressure through the HRS material to differential pressure through the calibration cotton, is fixed at β > 1 to increase sensitivity to Micromat drift. Routine analysis of two sets of cottons is presented based on HRS calibration and control. There is no drift in in strumental readings over the 3-week and 6-week periods required to analyze the sets of cottons.
Complex Char Formation in Flame-Retarded Fiber/Intumescent Combinations: Physical and Chemical Nature of Char1
Authors: Kandola Baljinder K. , Horrocks A. Richard
Published: March 2008

Char forming polymers, particularly cellulosics, can best be flame retarded by chem icals that function in the condensed phase. Under heat or fire conditions, these flame retardants enhance crosslinking and aromatization reactions of the polymer at the ex pense of volatilization, leading to increased char formation. Intumescent systems are also used to increase the flame retardancy of polymers. Under the action of heat, these compounds form a foamed char, which then acts as an insulative barrier to the under lying material against heat and flame. Our recent research has shown that if certain intumescents are used on flame retardant cellulosic fibers, the combined fibrous and intumescent chars that form are more than expected in quantity, with great mechanical strength and reduced oxygen permeability and sensitivity to oxidation. Within this so- called "char-bonded" structure, there is clear evidence of bonding between cellulosic fibers and intumescent char components. In our previous publications, we discussed the methodology of forming novel, thermally responsive, barrier textile fabrics com prising flame retardant cellulosic fibers in which intumescent systems are dispersed, the formation mechanism of char-bonded structures, and evidence of the interactions occurring between these components. This work extends to understanding the physical and chemical nature of the char for a variety of flame retardant viscose and cotton/ intumescent compositions.
Evaluating Yarn Crimp with Fractal Geometry
Authors: Tae Jin Kang  , Jae Yeol Lee  , Chung Kwansoo , Seung Goo Lee
Published: March 2008

Fractal geometry is used to evaluate the irregularities of crimped filament yarns. To measure the fractal dimension of textured filament yarns, methods based on the box counting dimension, the compass dimension, and the equipaced dimension are applied to digital images of the textured filament yarns, obtained using a charge coupled device (CCD) camera. For textured PET filament yams, as the crimp and twist level increase, higher values of fractal dimension are obtained, confirming that the fractal dimension can be used to evaluate fiber crimp. The fractal dimension and crimp also show an exponential relationship, which is well verified experimentally. Therefore, time-consuming direct measurements of fiber crimp may be effectively replaced by this automatic process, based on the acquisition of crimp images and fractal dimension analysis. The ideal sine wave. which has an equal length, crimp, and twist per meter, is synthesized as a topological model to study the physical properties of crimped yarn. This sine wave study shows that the major parameter of the crimped structure is the period of the crimp, and the dominant effect of yarn shrinkage development in boiling water is the increment of crimp amplitude.
Effect of Fiber Structure on Heat of Wetting of Cotton and Regenerated Cellulosic Fibers
Authors: Mizutani Chiyomi , Tsuj Yoshinobu , Bertoniere Noelie
Published: March 2008

A new calorimeter is constructed to precisely measure the heat of wetting of cotton, regular viscose rayon, high wet strength viscose rayon, and Tencel®. Our purpose is to investigate the relationship between the heat of wetting and structural characteristics of fibers such as crystal and fiber structure, degree of crystallinity, and water absorbency properties (water regain, moisture regain, and bound water content of fibers). Despite its relatively high water regain, cotton has the lowest heat of wetting among the fibers studied so far. The heat of wetting of cellulosic fibers depends slightly on fiber and crystal structure but decreases proportionally with the increasing degree of crystallinity of the fibers. The heat of wetting is closely related to the amount of bound water estimated by differential scanning calorimetry. These results are discussed from the viewpoint of designing high performance cellulose materials.
Control of Dye Concentration, pH, and Temperature in Dyeing Processes
Authors: Huang Chang-Chiun , Yu Wen-Hong
Published: March 2008

Dyeing processes are receiving growing attention in the textile industry because of the high demand for quality products. Commonly, dye concentration, pH, and temperature in the dyebath are the factors that most affect shade and coloration uniformity of dyed goods. To achieve quality assurance, control of dye concentration, pH, and temperature is definitely required. Since such factors behave nonlinearly and interact, it is almost impossible to create an exact mathematical model. As a consequence, control by conven tional means is very difficult. One approach to dealing with such a complex process is fuzzy control, which simulates the decision-making activities of experienced experts and employs a reasoning scheme to infer control actions. A small laboratory scale experiment has yielded results showing that fuzzy control is able to control dye concentration, pH, and temperature at the desired values.
Parental Contributions to Southeast Asian American Adolescents' Well-Being
Authors: Ying Yu-Wen , Han Meekyung
Published: March 2008

Informed by acculturation, ecological, and social capital theories, the study examined the contribution of parental acculturation, parental involvement, and intergenerational relationship to well-being in Southeast Asian American adolescents. Using data from the Children of Immigrants Longitudinal Study, 491 Southeast Asian American adolescents and their parents comprised the sample. Path analysis showed that parental involvement fully mediated the effect of parental acculturation on intergenerational relationship, whereas intergenerational relationship mediated the effect of parental involvement on child outcomes. Service implications are discussed.
Population Exposure‐Response Modeling of Metformin in Patients With Type 2 Diabetes Mellitus
Authors: Hong Ying , Rohatagi Shashank , Habtemariam Bahru , Walker Joseph R. , Schwartz Sherwyn L. , Mager Donald E.
Published: March 2008

The exposure‐response properties of metformin were characterized in 12 subjects with type 2 diabetes mellitus. The time course of drug concentration and effects on fasting plasma glucose and lactic acid concentrations were used from a study in which subjects received 500 mg of metformin twice daily for 5 days followed by 850 mg twice daily for 5 days. Pharmacokinetic sampling included morning trough concentrations obtained on days 7 to 9 and rich sampling (15 time points) on day 10. Fasting plasma glucose and lactic acid concentrations were measured on days 0 to 10 and served as biomarkers of therapeutic effect and tolerability, respectively. A population pharmacokinetic/pharmacodynamic analysis was conducted using nonlinear mixed effects modeling. Metformin pharmacokinetics were described using a 1‐compartment model with first‐order absorption. Population mean estimates (relative standard error [RSE]) of clearance (CL/F) and volume of distribution were 79.0 L·h−1 (6.8%) and 648 L (13.8%), respectively. Covariate analyses revealed that creatinine clearance (CLCR) significantly influenced metformin CL/F [CL/F = 79.0·(CLCR/80)0.822]. An indirect response model was applied to describe the ***antihyperglycemic effect of metformin. Population mean estimates (RSE) of baseline fasting plasma glucose and the drug concentration producing half‐maximal effect were 241 mg·dL−1 (4.6%) and 4.23 mg·L−1 (31.0%). An empirical linear model was used to describe a slight progressive increase in fasting lactic acid during metformin treatment with an estimated slope coefficient (RSE) of 0.0005 mM·mL·ng−1 (38.1%). Model evaluation by predictive check and nonparametric bootstrap analysis suggested that the proposed model is robust, and parameter values were estimated with good precision. Simulations suggested that the clinical utility of metformin was maintained over the dose range evaluated with respect to fasting plasma glucose and lactic acid response.
Achievement Place
Authors: Hoefler Sharon A. , Bornstein Philip H.
Published: March 2008

In recent years there has been a move away from the traditional institutionalization of deviant members of society and a step toward community-based treatment models. The present paper summarizes and analyzes one such community-based treatment facility for predelinquent boys. Three distinguishing features of the Achievement Place program are elaborated on in some detail: (1) the utilization of a token economy point system as a primary therapeutic tool, (2) the development of a series of well-controlled experiments enabling the establishment of functional relationships across behaviors, and (3) the training of teaching-parents. A variety of target behaviors are systematically reviewed. Overall evaluation of the Achievement Place program is undertaken in light of a number of issues considered relevant to scientific investigation. Recommendations are made for continued research to define more clearly the parameters of the existing model.
Training Techniques for Staff in Group Homes for Juvenile Offenders
Authors: Maloney Dennis M. , Phillips Elery L. , Fixsen Dean L. , Wolf Montrose M.
Published: March 2008

The proliferation of group homes and halfway houses for delinquents has increased the need for trained houseparents. The study investigated the effects of instructions, feedback, and modeling as training methods upon selected interpersonal parenting behaviors of six "teaching-parents" in three group homes. The homes were based on the "Teaching-Family" or "Achievement Place" model. The use of a multiple-baseline research design indicated that while instructions plus feedback were sufficient to teach some behaviors to some teaching-parents, the addition of model-imitation was generally more successfuL The importance of modeling in training correctional staff was discussed.
Schools and the Delinquency Experience
Authors: Polk Kenneth
Published: March 2008

The basic proposition examined here is that school experience is an important factor in understanding delinquency but that before this statement can be examined, it is necessary to elaborate an institutional theory which weaves together family-school-adult work role linkages. Secondary data and findings drawn from an ongoing cohort study of 284 adolescent males in the Pacific Northwest are used to show that adult success is related to school success, school success is related to family status characteristics, school status and social class exert independent effects on delinquency, and that adult careers, both successful and deviant, are functions of adolescent school and delinquency labels.
Persuasive Communication of Risk Information: A Test of Cue Versus Message Processing Effects in a Field Experiment
Authors: Verplanken Bas
Published: March 2008

Portions of the elaboration likelihood model of persuasion were tested in a natural selling with adults of various ages and educational backgrounds as subjects. The persuasive communication concerned risks of largl-scale use of coal for electricity production. The dependent variable was attitude change. Elaboration likelihood (EL) was operationalized through involvement and need for cognition. Highly credible sources were found to be more persuasive than less credible sources for low-EL but not for high-EL subjects. More persistence of attitude change (measured 14 months later) and stronger beliefs-attitude-intention consistency were found for high- than for low-EL subjects. Analyses of separate effects of involvement and need for cognition indicated that the two factors interacted concerning effects of source credibility. Need for cognition was related to attitude persistence. Involvement moderated beliefs-attitude-intention consistency, and need for cognition moderated attitude-intention consistency. Both factors were related to the route to persuasion.
Research Note: Run Silent, Run Deep — Cultural Influences on Organizations in the Far East
Authors: Hall Richard H. , Weiman Xu
Published: March 2008

There is a continuing debate regarding the extent to which organizations are culture-free or culture bound. A recent article suggests that while cultural factors are important in the growth of organizations, they are less important in terms of structural characteristics. This same article also suggests that Japanese and Chinese organizations share the same basic Confucian culture. We argue here that the Chinese and Japanese cultural traditions have major differences and that these play out in terms of important differences in organizational structure and operations.
Confucian Family Values and Childless Couples in South Korea
Authors: Yang Sungeun , Rosenblatt Paul C.
Published: March 2008

The Korean family has long met Confucian values by producing children to maintain and support the paternal family line, but in South Korea's transition to a low birth rate, an increasing number of couples have remained childless. Have Confucian family values been abandoned? In this study, 103 young single South Koreans wrote protocols describing their thoughts about childless couples and having children. Most of them viewed childless couples negatively and said that they planned to have children of their own. Confucian values were clearly central in what students wrote about childlessness. The results suggest that the increase in voluntary childlessness does not mean that Confucian values have been abandoned by young South Koreans. Confucian family values seem to remain primary, but they may be reinterpreted or reluctantly violated because economic and other circumstances make it difficult or impossible to meet those values in the South Korean context.
Same-Sex Couples
Authors: Oswald Ramona Faith , Kuvalanka Katherine A.
Published: March 2008

In this article, the authors present a typology for organizing our current knowledge regarding same-sex couples in the United States who have and have not established legal ties between partners. This framework is complemented by a discussion of key rulings that define what is legally possible as well as the introduction of “legal consciousness,” a construct for examining how perceptions of legal authority drive engagement with the legal system. Finally, the authors use their analysis to generate questions for future research and discuss policy and practice implications.
A cloze-up on the C-Test: a study in the construct validation of authentic tests
Authors: Klein-Braley Christine
Published: March 2008

Cloze tests and C-Tests are both tests of reduced redundancy based on the theory of general language proficiency. This paper presents the theory and shows first why cloze tests are unsatisfactory operalizations of the theory and the ways in which C-Tests are technically superior. It then reports the various investigations which have been performed in the construct validation of C-Tests and discusses their relevance to the original theory. Four hypotheses are set up relating to linerarity, parallelism, prediction of difficulty and processing strategies. The results obtained with the C-Tests support these hypotheses.
What does it mean to know howto use a language? An essay on the theoretical basis of language testing
Authors: Spolsky Bernard
Published: March 2008

Language testing and linguistic theory must both try to define language knowledge and use. There are three main approaches. The Structural claim, which assumes that knowledge can take the form of a grammar or structural description of the language, forms the basis of discrete point tests. The Functional approach assumes that the nature of language knowledge is best captured by listing the various uses to which it can be put; it is embodied in the communicative competence model, the notional-functional curriculum, and the interest in teaching and testing pragmatics. The General Proficiency claim is based on the notion that individuals vary in possessing measurable amounts of an indivisible body of knowledge. It underlies arguments for a general factor underlying batteries of tests or for the trait measured by certain test methods like the cloze. The theoretical strengths and weaknesses of these approaches and the impossibility of showing that any one is completely correct forces us to consider all three as basic to testing. Anybody who knows a second language must be assumed to have all three kinds of knowledge, so that we can only achieve the full picture of language proficiency if we use many different measuring method and know what trait is being tapped by each test.
Principles for language tests within the 'discourse domains' theory of interlanguage: research, test construction and interpretation
Authors: Douglas Dan , Selinker Larry
Published: March 2008

This article considers an alternative framework for handling the language testing enterprise and proposes some tentative theoretical hypotheses concerning principles of language testing. It is the writers' view that taking account of the perspective of interlanguage domain engagement and contextualization in testing research, production and interpretation allows for a richer conceptualization of the language testing process.
A long-term research agenda for the Test of Written English
Authors: Stansfield Charles W. , Ross Jacqueline
Published: March 2008

In April 1987, the TOEFL Research Committee commissioned a project designed to develop a long-range research agenda for the Test of Written English (TWE). The objective of the project was a paper that would outline basic issues in the determination of the validity and reliability of the test. The outline could subsequently be used to motivate and guide researchers in the conceptualization and design of TWE research projects. This paper is the principal product of the project commissioned by the TOEFL Research Committee.
How do subject specialists construe classroom language proficiency?
Authors: Elder Catherine
Published: March 2008

Recent research on rater variation (e.g., Barnwell, 1989; Douglas and Selinker, 1990; Hadden, 1991) raises the question of whether 'linguistically naive' subject specialists may be better equipped than language experts to judge the effectiveness of particular areas of non-native speaker communica tion. This question is investigated with reference to a classroom-based observation schedule which was developed to assess the English language proficiency of non-native speaker graduates training as secondary mathema tics and science teachers. The article examines aspects of rater behaviour as evidenced in recent trials.

The schedule was applied to observations of actual performance in the maths and science classroom as well as to the viewing of a number of videoed segments of classroom interaction. Ratings were elicited from two groups of assessors: nine ESL teachers and eight subject specialists (maths/science teachers/teacher trainers). Findings reveal significant correlations between subject specialists' and language teachers' overall judgements of communica tive effectiveness, but differences between the two groups with respect to their ratings of particular dimensions of language use and to the weighing of these dimensions in relation to global proficiency assessments.
Norms appropriacy of achievement tests: Spanish-speaking children and English children's norms
Authors: Davidson Fred
Published: March 2008

Appropriacy of a nationally standardized test normed on English speakers but used with non-English speaking students is examined. Data from the 1988-89 school year in Illinois are analysed via reliability comparison, exploratory factor analysis (for comparison of dimensionality via principal components analysis) and comparison of variances. Generally, it appears that the use of this test was statistically defensible. This finding does not, however, speak to the need for additional measures.
In search of the ethical test
Authors: Lynch Brian K.
Published: March 2008

The central question to be addressed here is whether any test can be defended as ethical, or moral. Ethicality is defined in terms of issues such as harm, consent, confidentiality of data and fairness. Frameworks for determining equity of edu cational opportunity are presented and discussed. A statewide assessment project in Victoria, Australia (the Learning Assessment Project) is then examined in relation to these concerns, and the possibility of more ethical approaches to testing is considered.
Three-Dimensional Construction with Mobile Robots and Modular Blocks
Authors: Werfel Justin , Nagpal Radhika
Published: March 2008

We present a decentralized algorithmic approach to automatically building user-specified three-dimensional structures from modular units. Our bipartite system comprises passive units (blocks), responsible for embodying the structure and determining where further units can legally be attached, and active units (robots), responsible for transporting passive units. The algorithmic issues are correspondingly decomposed into two parts: (1) deciding where passive units may be attached; and (2) getting them to those locations. For the first part, we give simple, scalable rules for attachment and prove that they will reliably lead to the construction of any desired structure from a large class of three-dimensional shapes. For the second part, we compare three approaches: random movement, systematic search and gradient-following; each approach is successively faster but requires more communication overhead and/or unit capabilities. The system we describe enables guaranteed construction of desired structures using very simple agent algorithms, taking a high-level specification as the only required input. The topic of collective construction is related to the problems of programmed self-assembly and self-reconfiguration in modular robots, and the rules governing block attachment presented here may be usefully applied to such systems.
Distributed Self-Reconfiguration of M-TRAN III Modular Robotic System
Authors: Kurokawa Haruhisa , Tomita Kohji , Kamimura Akiya , Kokaji Shigeru , Hasuo Takashi , Murata Satoshi
Published: March 2008

A new prototype of a self-reconfigurable modular robot, M-TRAN III, has been developed, with an improved fast and rigid connection mechanism. Using a distributed controller, various control modes are possible: single-master, globally synchronous control or parallel asynchronous control. Self-reconfiguration experiments using up to 24 modules were undertaken by centralized or decentralized control. Experiments using decentralized control examined a modular structure moved in a given direction as a flow produced by local self-reconfigurations. In all experiments, system homogeneity and scalability were maintained: modules used identical software except for their ID numbers. Identical self-reconfiguration was realized when different modules were used in initial configurations.
Collective Actuation
Authors: Campbell Jason , Pillai Padmanabhan
Published: March 2008

Modular robot designers confront inherent tradeoffs between size and power. Smaller, more numerous modules increase the adaptability of a given volume or mass of robot, allowing the aggregate robot to take on a wider variety of configurations, but do so at a cost of reducing the power and complexity budget of each module. Fewer, larger modules can incorporate more powerful actuators and stronger hinges, but at a cost of overspecializing the resulting robot in favor of corresponding uses. In this paper we describe a technique for coordinating the efforts of many tiny modules to achieve forces and movements larger than those possible for individual modules. In a broad sense, our work aims to make actuator capacity and range at least partly fungible by algorithm design and ensemble topology, rather than being immutable properties of a particular module design. An important aspect of this technique is its ability to bend complex and large-scale structures and to realize the equivalent of large-scale joints. By enabling scalable joints, and the “muscles” that could actuate larger structures, our work makes it more likely that modular robot ensembles can successfully be scaled up in number and down in size.
Automatic Modular Assembly System and its Distributed Control
Authors: Terada Yuzuru , Murata Satoshi
Published: March 2008

Construction is difficult to automate because of its complexity. Introducing modularity into both structural components and a means of assembly solves the problem by simplifying the construction task. Based on this idea, we propose a novel concept of a fully automated construction system called the Automatic Modular Assembly System (AMAS). In this paper, we discuss the hardware system and distributed control method of AMAS. This system uses passive building blocks called “structure modules” and an assembler robot that is specialized to handle them. This “modular” concept drastically simplifies structural complexity. We have built a prototype model to evaluate its automatic construction capability. Then we introduce a distributed autonomous control for AMAS, which uses a gradient field to indicate the directions to the assembler robots. The gradient field is generated on the structure modules. To improve the efficiency, we introduce collision avoidance rules such as module relay and local negotiation via a blackboard. We also evaluate the overall performance of the distributed control with simulations.
Distributed Control Architecture for Self-reconfigurable Manipulators
Authors: Turetta A. , Casalino G. , Sorbara A.
Published: March 2008

In recent years self-reconfigurable modular robots have gained increasing interest from part of the international robotic community. Although recent robots of this type are characterized by advanced electro-mechanical designs, the development of their supporting control techniques have only registered strong results in the field of locomotion problems, while the manipulation capabilities of existing systems still appear to be quite limited. Aiming to provide a contribution along this latter direction, in this paper we propose a computationally distributed technique for controlling the motion of any tree-structured chain resulting from reconfiguration in its operational space. The presented strategy, which could actually be adopted when dealing with any kind of chain-based modular robotic system, turns out to be particularly well suited to self-reconfigurable structures for three main reasons: (i) it is not based on any explicit role assignment; all of the modules can be added, removed or exchanged online as required, with no impact on the overall control architecture; (ii) each module has only a very limited set of local information that must be known a priori and can be totally unaware of the remaining part of the chain; (iii) no external centralized controller is necessary; basic local processing and communication units onboard every module and a simple man—machine interface providing high-level commands are enough. A global self-coordinating behavior is automatically exhibited by the proposed technique at power-on or immediately after any configuration change as the result of a number of repeated data exchanges, performed online along the chain at every sampling interval. Although achievable performances depend on the available communication bandwidth, the convergence towards a final position error of zero is, however, always guaranteed. Moreover, because the computational burden required by every module is extremely light, the proposed technique represents an effective control solution that can be easily implemented onboard many of the low-cost and small control platforms available on existing self-reconfigurable robots.
Learning to Move in Modular Robots using Central Pattern Generators and Online Optimization
Authors: Sproewitz Alexander , Moeckel Rico , Maye Jérôme , Ijspeert Auke Jan
Published: March 2008

This article addresses the problem of how modular robotics systems, i.e. systems composed of multiple modules that can be configured into different robotic structures, can learn to locomote. In particular, we tackle the problems of online learning, that is, learning while moving, and the problem of dealing with unknown arbitrary robotic structures. We propose a framework for learning locomotion controllers based on two components: a central pattern generator (CPG) and a gradient-free optimization algorithm referred to as Powell's method. The CPG is implemented as a system of coupled nonlinear oscillators in our YaMoR modular robotic system, with one oscillator per module. The nonlinear oscillators are coupled together across modules using Bluetooth communication to obtain specific gaits, i.e. synchronized patterns of oscillations among modules. Online learning involves running the Powell optimization algorithm in parallel with the CPG model, with the speed of locomotion being the criterion to be optimized. Interesting aspects of the optimization include the fact that it is carried out online, the robots do not require stopping or resetting and it is fast. We present results showing the interesting properties of this framework for a modular robotic system. In particular, our CPG model can readily be implemented in a distributed system, it is computationally cheap, it exhibits limit cycle behavior (temporary perturbations are rapidly forgotten), it produces smooth trajectories even when control parameters are abruptly changed and it is robust against imperfect communication among modules. We also present results of learning to move with three different robot structures. Interesting locomotion modes are obtained after running the optimization for less than 60 minutes.
Airborne LiDAR for DEM generation: some critical issues
Authors: Xiaoye Liu
Published: March 2008

Airborne LiDAR is one of the most effective and reliable means of terrain data collection. Using LiDAR data for digital elevation model (DEM) generation is becoming a standard practice in spatial related areas. However, the effective processing of the raw LiDAR data and the generation of an efficient and high-quality DEM remain big challenges. This paper reviews the recent advances of airborne LiDAR systems and the use of LiDAR data for DEM generation, with special focus on LiDAR data filters, interpolation methods, DEM resolution, and LiDAR data reduction. Separating LiDAR points into ground and non-ground is the most critical and difficult step for DEM generation from LiDAR data. Commonly used and most recently developed LiDAR filtering methods are presented. Interpolation methods and choices of suitable interpolator and DEM resolution for LiDAR DEM generation are discussed in detail. In order to reduce the data redundancy and increase the efficiency in terms of storage and manipulation, LiDAR data reduction is required in the process of DEM generation. Feature specific elements such as breaklines contribute significantly to DEM quality. Therefore, data reduction should be conducted in such a way that critical elements are kept while less important elements are removed. Given the high-density characteristic of LiDAR data, breaklines can be directly extracted from LiDAR data. Extraction of breaklines and integration of the breaklines into DEM generation are presented.
Adaptive Behavior: Concurrent Validity
Authors: Heath Charles P. , Obrzut John E.
Published: March 2008

The concurrent validity of adaptive behavior was investigated for educable mentally retarded (EMR) and slow learners (SL). Fifty-seven EMR (N = 36) and SL ( N = 21) children completed the Children's Adaptive Behavior Scale (CABS) while teachers and parents completed the Adaptive Behavior Scale-School Edition (ABS-SE) and the Adaptive Behavior Inventory for Children (ABIC). Moderate correlations were found between the ABIC and CABS when total mean scores were compared to the Comparison Score on ABS-SE. Part 1 of the ABS-SE tends to have higher and more consistent correlations (convergent validity) with the ABIC and CABS than does Part 2 of the ABS-SE (discriminant validity). The CABS and ABIG were found to be closely related. Implications of the findings in terms of assessment are discussed.