bluuebunny/crossref_metadata_2025 huggingface dataset:
Design of a conductive fabric network by the sheet resistance method
Authors: Li Li  , Wai Man Au  , Tao Hua  , Kwok Shing Wong
Published: June 2011

Combining textiles with electronics has become a promising realm in the future development of textiles. A number of researches have been conducted to exploit the potential applications, such as sports, healthcare, etc. However, the growth of wearable electronic textiles in the market is being retarded. The reasons may refer to the poor appearance of current products in that consumers may consider the products to be ‘technical’ rather than ‘garments’, since aesthetics have been ignored as a result of focusing on the functionality of the textiles. Conductive fabrics have become one of the fundamental elements of wearable electronic textiles, which form an electrically conductive network to interconnect various electronic function units, such as textile electrodes, power sources, etc. However, it is necessary to solve the high-dimensional matrix in order to compute the resistance of the conductive network, which hinders the application of conductive fabrics in industry. Therefore, it is essential to develop a direct and fast method to aid the fashion designer without an electronic background to compute the resistance of the conductive fabric so as to meet the high demand for rapid prototype development of wearable electronic garments. This paper describes a systematic approach to calculate the resistance based on the sheet resistance and number of unit squares from a macroscopic view. The experimental results demonstrated that this method could readily calculate the resistance of conductive fabrics as long as the sheet resistance and the number of unit squares are known. In addition, the proposed method can be applied to other types of conductive fabrics.
Comparative study on the mechanical properties of elastic, electro-conductive hybrid yarns and their input materials
Authors: Schwarz Anne , Kazani Ilda , Cuny Laetitia , Hertleer Carla , Ghekiere Filip , De Clercq Geert , Van Langenhove Lieva
Published: June 2011

The development of electro-conductive yarns and the characterization of their conductive properties has gained importance over the past years. However, for their later application, not only the electro-conductive properties of the yarns are important, but also their mechanical characteristics. Hence, this paper presents an analysis of the mechanical behaviour of elastic, electro-conductive hybrid yarns. The yarns comprised an elastic core yarn and electro-conductive winding yarns. Studying the mechanical properties of the hybrid yarns, as well as their corresponding input yarns, it could be proven that the overall good strength and elongation behaviour of the hybrid yarns was depended on the properties of the input yarns, as well as on the yarns’ production parameters.
Estimation of the surface energy of chemically and oxygen plasma-treated regenerated cellulosic fabrics using various calculation models
Authors: Peršin Zdenka , Stenius Per , Stana-Kleinschek Karin
Published: June 2011

The aim of this work was to evaluate and compare the surface energies (SFEs) of regenerated cellulose fabrics modified by washing, bleaching, conventional chemical treatment (slack-mercerization), and plasma treatment. Three commonly used methods of estimating apolar, polar, and acid/base contributions were applied: geometric mean (GM), using diiodomethane (MI) and water as probes; van Oss—Good—Chaudhury (vOGC), using MI, tetrahydrofuran (THF), and chloroform (CF); and Owens—Wendt—Rabel—Kaelble (OW), using water, MI, THF, CF, ethanol and ethylene glycol.

All treatments gave rise to more hydrophilic materials, as indicated by a decrease in the water contact angle. The GM and OW methods both showed that the polar component of the SFE increased after bleaching or conventional chemical treatment and, in particular, after plasma treatment. The vOGC method showed much smaller effects and indicated decreasing polarity after plasma treatment. This was probably due to the use of acid and base probes that did not contain hydroxyl groups in the determination of vOGC parameters, that is, the effect of the treatments was to introduce acid functionalities that could interact strongly with hydroxyls (hydrogen bonding) but not with the Lewis base THF or Lewis acid CF.
Studies of fluorinated methylacrylate copolymer on the surface of cotton fabrics
Authors: Jun Luo  , Qing Wu  , Huang Heng-chao , Chen Jian-jun
Published: June 2011

A fluorine-containing methylacrylate copolymer latex has been synthesized by emulsion polymerization and was used as a water- and oil-repellent agent to treat some pure cotton woven fabrics at different dry and curing temperature. The treated cotton fabric surfaces were investigated by attenuated total reflectance infrared analysis and angle-dependent X-ray photoelectron spectroscopy directly. The analysis results could agree with the fluorine-containing copolymer real situation on the fabrics surface much more, and could indicate, factually, surface properties of treated or modified material rather than copolymer film. It was found that fluorine elements are enriched at the air-polymer interface and fluorine content of the treated cotton fabrics surface decreases with increasing analysis depth, which depends on heating and cooling experience, such as annealing and quenching. Furthermore, the results showed that almost the same effect can be attained using this copolymer curing from 100°C to 175°C; the relatively low curing temperature is very valuable and advantageous for some fabrics which would yellow easily at higher temperatures. The water- and oil-repellency grade of treated cotton fabrics by the fluorine-containing methylacrylate copolymer latex increases with an increase on fluorine content on the surface.
Smart textiles: an explorative study of the use of magnetron sputter deposition
Authors: Depla Diederik , Segers Siegfried , Leroy Wouter , Van Hove Tom , Van Parys Marc
Published: June 2011

Reactive magnetron sputtering is a widely used deposition technique in different application areas. In this study its use is evaluated for the deposition of metal thin films (Al, Cu and Ti) and oxide thin films (Al2O3, TiOx) on woven and nonwoven substrates. The study shows that good adhesion can only be achieved when the substrate is pre-treated in a glow discharge. The influence of the substrate on the reflectivity of Al and Cu thin films was investigated. For conductive textile applications, the resistivity of metal thin films and TiOx was investigated.
U.S. Hispanic/Latino Biblical Interpretation: A Critique from within
Authors: Martínez Aquiles Ernesto
Published: June 2011

This article is a critique of the philosophy and praxis of biblical interpretation as conceptualized and modeled by some of the most prominent Latino/a theologians in the U.S. In addition to problematizing this issue with questions and comments of relevance for Hispanic and church realities, the writer—a Bible scholar himself and an ordained minister who believes in the integration of theory and practice, and someone involved in issues affecting this ethnic constituency—also provides some practical suggestions to move the field of biblical interpretation to the next level. The hope is that some of his colleagues, and even those who belong to a different ethnic group, take these comments into account so that biblical scholarship is useful for the guild, Hispanic/Latino theology in general, the life and mission of the Church, and society as a whole.
Disrupted by Luke–Acts
Authors: Duba Arlo
Published: June 2011

This study of the Luke–Acts corpus recounts the continually expanding inclusiveness of the Christian faith from Jerusalem to Europe and to the whole world. This reading includes the disruption of a basic Jewish exclusivist orientation in the choosing of the disciples, through redefinitions of “neighbor” in Samaritans, a supernaturalism-infused incident on the road to Gaza with a eunuch of ambiguous gender/sexuality, a metaphor of the sheet let down from heaven leading to table fellowship with a Roman centurion, to Paul’s disrupted Asian mission that took him to Macedonia and the inclusion of Europe.
Destabilizing the National Hegemonic Narrative
Authors: Bernardino-Costa Joaze
Published: June 2011

Theories of decolonization (principally those of Dussel, Quijano, and Mignolo), hold that knowledge is produced not from a neutral and universal position but from the different positions of actors within a hierarchical structure of power. Analysis of the thought of Brazil’s unionized domestic workers as a subaltern voice reveals that these workers’ political activism produces a form of knowledge that articulates class, race, and gender and allows us to problematize the national hegemonic narrative, destabilizing the hegemonic cultural meanings structured by the myths of racial democracy and the good master.
The role of dialogue in the ontogeny and phylogeny of early symbol combinations: A cross-species comparison of bonobo, chimpanzee, and human learners
Authors: Gillespie-Lynch Kristen , Greenfield Patricia M. , Lyn Heidi , Savage-Rumbaugh Sue
Published: June 2011

What are the evolutionary and developmental origins of linguistic creativity? Cross-species comparison of the clade consisting of bonobo, chimpanzee, and human suggests that creative word combinations arise from conversation. Analysis of conversational data shows that novel symbol combinations are initially dependent upon conversational input – through the processes of deferred imitation and joint construction – for a bonobo and a chimpanzee exposed to a humanly devised symbol system, as well as for a human child. In all three species, reliance on conversational input for novel symbol combinations fades with development, as novel symbol combinations come to be constructed more independently. These findings resolve the controversy between the claim that ape language is limited to imitation and the claim that apes are not capable of imitation. Imitation, like conversational co-construction, does not differentiate between bonobo, chimpanzee, and human; instead, imitation and co-construction differentiate stages of learning and development across all three species.
On the role of morphological richness in the early development of noun and verb inflection
Authors: Xanthos Aris , Laaha Sabine , Gillis Steven , Stephany Ursula , Aksu-Koç Ayhan , Christofidou Anastasia , Gagarina Natalia , Hrzica Gordana , Ketrez F. Nihan , Kilani-Schoch Marianne , Korecky-Kröll Katharina , Kovacˇevic´ Melita , Laalo Klaus , Palmovic´ Marijan , Pfeiler Barbara , Voeikova Maria D. , Dressler Wolfgang U.
Published: June 2011

This study proposes a new methodology for determining the relationship between child-directed speech and child speech in early acquisition. It illustrates the use of this methodology in investigating the relationship between the morphological richness of child-directed speech and the speed of morphological development in child speech. Both variables are defined in terms of mean size of paradigm (MSP) and estimated in a set of longitudinal spontaneous speech corpora of nine children and their caretakers. The children are aged 1;3–3;0, acquiring nine different languages that vary in terms of morphological richness. The main result is that the degree of morphological richness in child-directed speech is positively related to the speed of development of noun and verb paradigms in child speech.
Judith Butler’s ‘not particularly postmodern insight’ of recognition
Authors: Ferrarese Estelle
Published: June 2011

Although Judith Butler regards recognition as the theme unifying her work, one finds a striking absence of dialogue between her and the authors of the normative theories of recognition — Honneth, Habermas, Ricoeur, etc. In the present article I seek to call into question this sentiment, shared by the two sides, of a radical theoretical heterogeneity. First I seek to show that the theory of performativity which Butler developed initially, contrary to all expectations, sets her relatively apart from the tradition to which she conforms (the French reading of Hegel), and brings her closer to the proposition represented by the normative theories of recognition in general, and that of Honneth in particular. Then I highlight how the recent modulations in her theory, through the appearance of the idea of a constitutive vulnerability, which enables her to found an ethics, undermine for once and for all the claim of irreducibility maintained by each of the two theories in relation to the other.
The parergonal politics of Barack Obama
Authors: Caputi Mary
Published: June 2011

This article offers a Derridean analysis of Barack Obama’s statement that, as president, he would be willing to negotiate with political actors dubbed ‘terrorists’, ‘rogues’, ‘enemies’, or members of the ‘axis of evil’. The article argues that the Derridean concept of the ‘parergonal’ is useful, as is the Derridean distinction between hospitality and tolerance. This is because a parergonal approach to politics, evidenced in a willingness to listen to those that others have ignored, and to include those left out, illustrates hospitality’s commitment to allowing alterity to remain untranslated: the other is accepted as other. Undoubtedly, this deconstructive aspect of Obama’s political outlook proves threatening to traditional Americans, for its hospitality could potentially rewrite America’s hegemonic position in the world arena.
Variability in the Management of Idiopathic Sudden Sensorineural Hearing Loss
Authors: Coelho Daniel H. , Thacker Leroy R. , Hsu David W.
Published: June 2011

Objectives

To evaluate current trends in the management of idiopathic sudden sensorineural hearing loss (ISSNHL), determine if variance in diagnostic and treatment protocols exists, and compare diagnostic and treatment strategies of ISSNHL between nonotologists/neurotologists (NONs) and otologists/neurotologists (ONs).

Study Design

Cross‐sectional survey of practicing otolaryngologists.

Setting

Otolaryngology practices within the United States.

Subjects and Methods

In January 2010, a survey was mailed to 500 NONs and 500 ONs. Data were collected and analyzed using χ2, standard deviations, and variance.

Results

A variety and distribution of responses were seen in the definition of ISSNHL, including dB loss necessary for diagnosis, number of consecutive frequencies involved, and maximum duration of hearing loss. Differences in diagnostic tools were also seen, with 50.4% of respondents (NON 34.2%, ON 66.7%;P=. 0001) always using magnetic resonance imaging in their workup. Of the total respondents, 26.7% (NON 35.0%, ON 18.3%;P<. 0001) preferred oral steroids alone; 22.1% (NON 11.7%, ON 32.5%;P<. 0001) preferred a combination of oral and intratympanic steroids. Of the respondents, 68.6% (NON 57.5%, ON 80.0%;P=. 0003) would continue with additional treatment after partial response; 20.8% (NON 33.3%, ON 8.3%;P<. 005) would retreat with oral steroids alone and 46.6% (NON 35.8%, ON 57.3%;P<. 05) with intratympanic injections. Overall, 69.2% (NON 45.8%, ON 92.5%;P=. 0001) were very comfortable managing ISSNHL.

Conclusion

Significant differences exist in the diagnosis and treatment of ISSNHL. Such lack of uniformity highlights the need for strong evidence‐based research—ultimately leading to formalized practice guidelines and educational outreach.
A Novel Low‐Cost Sinus Surgery Task Trainer
Authors: Malekzadeh Sonya , Pfisterer Michael J. , Wilson Brette , Na Hana , Steehler Matthew K.
Published: June 2011

Sinus surgery simulation has proven to be a valuable teaching tool, yet the cost of many simulators limits the incorporation of this technology into training programs. The authors developed an inexpensive endoscopic sinus surgery task trainer and evaluated its value as a means of developing basic endoscopy and sinus surgery skills. For less than 5 US dollars, the training model was constructed using gelatin and embedded with reusable, recyclable, and readily available materials. Ten attending otolaryngologists performed nasal endoscopy and 5 specific tasks using this model, followed by completion of a survey evaluating the value of the model as a teaching tool. The model scored very well in promoting camera skills, instrumentation, and hand‐eye coordination. This easily reproducible, highly rated sinus surgery task trainer can serve as an alternative to more expensive simulators. Studies are under way to determine its validity and effectiveness as both a teaching and assessment tool.
Language and Persuasion: Linguistic Extremity Influences Message Processing and Behavioral Intentions
Authors: Craig Traci Y. , Blankenship Kevin L.
Published: June 2011

The present studies explore the role of linguistic extremity on message processing, persuasion, and behavioral intentions. Past research has found that the use of intense language has led to increases in attitude—behavior consistency. The authors present research that suggests that one reason for these effects is because linguistic extremity increases message processing, a common antecedent to attitude strength. Across two studies, linguistic extremity increased message processing relative to a control message. Study 2 replicated the increased processing effects with a different topic, and linguistic extremity led to increases in intentions to sign a petition when the message contained strong arguments. Furthermore, increases in behavioral intentions were mediated by participants’ amount of processing. Implications for linguistic extremity as a linguistic marker of attitude strength are discussed.
Beastly: What Makes Animal Metaphors Offensive?
Authors: Haslam Nick , Loughnan Steve , Sun Pamela
Published: June 2011

Animal metaphors convey a wide range of meanings, from insulting slurs to expressions of love. Two studies examined factors contributing to the offensiveness of these metaphors. Study 1 examined 40 common metaphors, finding that their meanings were diverse but centered on depravity, disagreeableness, and stupidity. Their offensiveness was predicted by the revulsion felt toward the animal and by the dehumanizing view of the target that it implied. Study 2 examined contextual factors in metaphor use, finding that the offensiveness of animal metaphors varies with the tone of their expression and the gender and in-group/out-group status of their targets. These variations influence offensiveness by altering the extent to which the target is ascribed animalistic properties.
Diagnosing EAP writing ability using the Reduced Reparameterized Unified Model
Authors: Kim Youn-Hee
Published: June 2011

Despite the increasing interest in and need for test information for use in instructional practice and student learning, there have been few attempts to systematically link a diagnostic approach to English for academic purposes (EAP) writing instruction and assessment. In response to this need for research, this study examined the extent to which the diagnostic information generated by the Reduced Reparameterized Unified Model (Reduced RUM; Hartz, Roussos, & Stout, 2002) was a discriminant, accurate, and reliable method of determining student performance in EAP writing. Ten English as a second language (ESL) teachers assessed 480 Test of English as a Foreign Language™ Internet-based test (TOEFL® iBT ) independent essays using the Empirically-derived Descriptor-based Diagnostic (EDD) checklist, which consisted of 35 concrete, fine-grained descriptors. The resultant ratings were then analyzed using Arpeggio, the estimation software of the Reduced RUM. The findings showed that the skills diagnosis approach not only classified skill masters and non-masters accurately and reliably, but that it also had high discriminant function, with only a small number of students classified into flat profiles. However, concerns were raised with regard to the diagnostic power of some descriptors and the stability of one writing skill parameter (i.e., mechanics). The theoretical and pedagogical implications of the use of diagnostic assessment in EAP writing are discussed in this paper, as are suggestions for future research in applying psychometric diagnostic assessment models to performance assessment.
Confidence scoring of speaking performance: How does fuzziness become exact?
Authors: Jin Tan , Mak Barley , Zhou Pei
Published: June 2011

The fuzziness of assessing second language speaking performance raises two difficulties in scoring speaking performance: indistinction between adjacent levels and overlap between scales. To address these two problems, this article proposes a new approach, confidence scoring, to deal with such fuzziness, leading to confidence scores between two adjacent levels applied to three scales. Since confidence scores have to be transformed to an exact score for test interpretation and use, membership functions and rule bases are applied and a confidence scoring algorithm is developed. Confidence scoring is demonstrated in the paper by an example to facilitate easy understanding. The paper then describes a pilot study that was conducted to try out the confidence scoring design. Initial results reveal that: first, confidence scoring is as feasible as traditional scoring; second, confidence scoring performs better in scoring dependability and in correlations with established benchmarks. At the end of the article, further studies are called for in order to build a validity argument and make further revisions to the confidence scoring method described here.
The development and maintenance of rating quality in performance writing assessment: A longitudinal study of new and experienced raters
Authors: Lim Gad S.
Published: June 2011

Raters are central to writing performance assessment, and rater development – training, experience, and expertise – involves a temporal dimension. However, few studies have examined new and experienced raters’ rating performance longitudinally over multiple time points. This study uses operational data from the writing section of the MELAB (n = 20,662 ratings), an international exam of English proficiency, to investigate the rating quality of new and experienced raters over three time periods of 12 to 21 months. Rating quality was operationalized in terms of rater severity and consistency, and estimates of those modeled using multi-facet Rasch methodology. Results indicate that, within one particular rating context, (1) novice raters, where initially differing in performance, learn to rate appropriately relatively quickly, (2) raters are able to maintain rating quality over time, and (3) rating volume and rating quality may be related. Implications for rater preparation, rater certification, and the notion of expert rater are discussed.
‘That’s part of everybody’s job’: the perspectives of health care staff in England and New Zealand on the meaning and remit of palliative care
Authors: Gott Merryn , Seymour Jane , Ingleton Christine , Gardiner Clare , Bellamy Gary
Published: June 2011

Background: the right for patients of all diagnoses to be in receipt of palliative care from an early point in the diagnosis of a life-limiting condition is now enshrined in policy in a number of countries and increased emphasis is placed upon the role of generalist palliative care. However, little is known as to how this policy is enacted on the ground.

Aim: to explore understandings of, and perceived roles in relation to, palliative care provision amongst generalist and specialist health care providers in England and New Zealand.

Design: qualitative data were collected via individual interviews and focus groups.

Setting/participants: participants comprised generalist and specialist palliative care providers working in a variety of settings in England ( n = 58) and New Zealand ( n = 80).

Results: the following issues with significant implications for this new phase of development for palliative care were identified: (1) difficulties with terminology and perceived roles/responsibilities; (2) problems of integrating palliative care into a generalist workload; (3) challenges in generalist/specialist partnership working; and (4) the potential negative consequences of specialization.

Conclusions: these data indicate that, within England and New Zealand, the policy rhetoric of universal palliative care provision is not being straightforwardly translated into service delivery and individual clinical practice. Further research is required to explore and evaluate different models of organization and service provision that empower ‘generalists’ to provide palliative care, without resulting in deskilling. Finally, definitional clarity at an academic/policy level is also needed.
Enhancing Student Learning in Marketing Courses
Authors: Hollenbeck Candice R. , Mason Charlotte H. , Song Ji Hee
Published: June 2011

The design of a course has potential to help marketing students achieve their learning objectives. Marketing courses are increasingly turning to technology to facilitate teaching and learning, and pedagogical tools such as Blackboard, WebCT, and e-Learning Commons are essential to the design of a course. Here, the authors investigate the research discussing the sources of satisfaction in web design and apply these concepts to website platforms used in traditional classes. The purpose of the study is to enhance student learning by identifying fundamental principles to be used when designing website platforms. Our study includes in-depth interviews with graduate and undergraduate students. Among both student groups, our analysis reveals five fundamental pedagogical principles for enhancing student learning through the use of technology: (a) student-to-student connectivity, (b) instructor-to-student interactivity, (c) goal efficiency, (d) quality content, and (e) student appeal. The authors discuss the importance of the presence of the five pedagogical principles and offer useful implications for marketing faculty and suggestions for future research.
The Cerebral Palsy Research Registry
Authors: Hurley Donna S. , Sukal-Moulton Theresa , Msall Michael E. , Gaebler-Spira Deborah , Krosschell Kristin J. , Dewald Julius P.
Published: June 2011

Cerebral palsy is the most common neurodevelopmental motor disability in children. The condition requires medical, educational, social, and rehabilitative resources throughout the life span. Several countries have developed population-based registries that serve the purpose of prospective longitudinal collection of etiologic, demographic, and functional severity. The United States has not created a comprehensive program to develop such a registry. Barriers have been large population size, poor interinstitution collaboration, and decentralized medical and social systems. The Cerebral Palsy Research Registry was created to fill the gap between population and clinical-based cerebral palsy registries and promote research in the field. This is accomplished by connecting persons with cerebral palsy, as well as their families, to a network of regional researchers. This article describes the development of an expandable cerebral palsy research registry, its current status, and the potential it has to affect families and persons with cerebral palsy in the United States and abroad.
Streptococcus pneumoniae Meningoencephalitis With Bilateral Basal Ganglia Necrosis
Authors: Magnus Jessy , Parizel Paul M. , Ceulemans Berten , Cras Patrick , Luijks Marloes , Jorens Philippe G.
Published: June 2011

Streptococcus pneumoniae ( S pneumoniae) is a common cause of bacterial meningitis, frequently leading to death or severe neurological impairment. We report an exceptional case of a 4-month-old boy with meningitis caused by S pneumoniae. Computed tomography (CT) and magnetic resonance imaging (MRI) examinations of the brain showed bilateral symmetrical necrosis involving the lentiform and caudate nuclei, as well as the thalamus. T1-weighted MR images showed patchy areas of increased signal intensity, consistent with hemorrhagic transformation of the lesions. Autopsy revealed widespread necrosis of the basal ganglia with clear signs of vasculitis. Severe complications of S pneumoniae meningoencephalitis are known in infants but to our knowledge, such lesions in the basal ganglia have only been reported thrice in adults and never in children.
California’s State Disability and Paid Family Leave Program with a Review of Other State Actions
Authors: Kilgour John G.
Published: June 2011

Effective 2004, California implemented the nation’s first Paid Family Leave (PFL) program. It is funded entirely by employee contributions and provides income replacement benefits for various family- and health-related reasons, including bonding with a new child. The program complements and interacts with various other preexisting benefit arrangements. California, four other states and Puerto Rico have long-existing temporary disability insurance (TDI) programs that provide income replacement for off-the-job injury and illness. In California, it is called State Disability Insurance (SDI). PFL was grafted onto the SDI program and, for most purposes, is an integral part of it. We now have 5 years of experience with PFL and a meaningful appraisal can now be made. By almost all measures, PFL has been a major success. There is a great deal of interest among other states in establishing a similar program and New Jersey (a TDI state) has already done so. Others may follow; however, it will be more difficult for the 45 states that do not already have a TDI program.
Fracture Behavior of Recyclable All-Polypropylene Composites Composed of α- and β-Modifications
Authors: Stocchi A. , Pettarin V. , Izer A. , Bárány T. , Czigány T. , Bernal C.
Published: June 2011

The fracture behavior of all-PP composites was studied under quasi-static loading conditions. Fracture toughness was evaluated by means of different fracture mechanics approaches depending on materials’ behavior. Composites consolidated at low temperature exhibited pop-in features and the failure occurs typically by delamination and tape stretching and fracture. With increasing consolidation quality – i.e., with increasing processing temperature – the delamination became less pronounced, and so the tape stretching occurred, before the specimens break. In composites consolidated at the highest temperature investigated (190°C), the laminate-like structure typical of self-reinforced composites produced according to film-stacking method was lost. Accordingly, composites behave as if they were only α-PP and β-PP matrices: α-rPP exhibited typical brittle fracture of α-PP, while β-rPP exhibited the stable behavior with fully yielded ligament before crack propagation commonly observed for β-PP. In general, stress–strain behavior changed from stable to unstable and fracture toughness strongly decreased as consolidation quality increased. Based on these results and previous findings, it can be concluded that the properties of self-reinforced PP composites can be tailored for a given application through the quality of consolidation.
Effect of ZnO Nano-Particles on The Dielectric Relaxation Behavior and Thermal Stability of Polycarbonate Host
Authors: Al Jaafari A.A. , Ayesh A.S.
Published: June 2011

The influence of ZnO nanoparticles on the dielectric properties, dielectric relaxation behavior, and thermal stability of PC host was investigated at different ZnO nanoparticles concentration. The dielectric study was carried out over a frequency range from 500 Hz up to 1 MHz as a function of ZnO concentration. Results obtained from the best fitting of relative permittivity data with Yan and Rhodes model reveal that the dielectric relaxation is not a single relaxation process and there are two values of relaxation time for each nanocomposite at room temperature and domain frequency range. Furthermore, addition of ZnO nanoparticles to PC host changes the dielectric properties of PC, mainly, increases relative permittivity, dielectric loss, and AC conductivity while decreases the impedance values of PC host. Moreover, effect of temperature on AC conductivity of ZnO-PC nanocomposites at 1 kHz was also considered. Besides, dielectric relaxation behavior of PC was investigated at 165°C (above the glass transition temperature of PC) in the domain frequency range. At this elevated temperature (165°C), dielectric loss data shows a single relaxation peak (α-relaxation) in the domain frequency range and was successfully fitted with Debye equation. Also, it was found that as the content of ZnO nanoparticles increases in the PC host the frequency of the peak maximum ( fmax) shifts toward higher frequency value and as a result decreases the value of relaxation time. Additionally, this study shows that the isothermal effect of ZnO nano particles on the α-relaxation of PC host is similar to the effect of temperature. Both of them have a linear dependence with ln( fmax). Furthermore, addition of ZnO nanoparticles to PC host will decrease the thermal stability and glass transition temperature of PC host. Finally, there is a strong evidence from the obtained dielectric and thermal results that addition of ZnO nanoparticles to PC host will highly enhance the chain mobility and also increase the polar character of PC host.
Experimental Investigations on Some Aspects of Machinability in Drilling of Glass Epoxy Polymer Composites
Authors: Basavarajappa S. , Venkatesh Abay , Gaitonde V.N. , Karnik S.R.
Published: June 2011

The glass epoxy polymer composites are extensively used for a wide variety of applications in aerospace, automotive, and chemical industries due to an excellent property profile. Even though these composites are produced as near net shapes, the machining has to be performed in the final stage of production. Drilling is one of the most common machining processes used to install the fasteners for assembly of laminates. However, the drilling of these composites is rather a difficult task due to the highly abrasive nature of reinforcement and hence there is a need to study the machining performance. An attempt has been made in this article to investigate the effects of spindle speed and feed on machinability aspects, namely, thrust force, hole surface roughness, and specific cutting coefficient during drilling of glass epoxy composites. The drilling experiments were performed as per full factorial design for both glass epoxy composites and silicon carbide-filled glass epoxy composite materials. The response surface methodology based mathematical models were developed for analyzing the effects of cutting conditions on machinability characteristics. The parametric analysis reveals that the silicon carbide-filled glass epoxy composite material provides better machinability compared to glass epoxy composite without the addition of filler.
Roots of Civil Rights Politics in Northern Churches: Black Migration to Saginaw, Michigan 1915 to 1960
Authors: McKether Willie
Published: June 2011

The southern-led civil rights movement was an important transformational period in the history of African American life and culture in the USA. While we know much about the social, economic, and political activities that occurred in southern cities in the 10 years preceding the civil rights movement, we know less about how parallel social processes developed in urban northern communities between 1946 and 1960 and how they prepared the black church for radical politics during the civil rights period. Black migration to Saginaw, Michigan serves as a case study to show how middle class migrants were the causal mechanism that secularized black churches through their overlapping memberships in status groups, black churches and secular organizations, and how this population helped to prepare black churches in Saginaw (and much of the north) for radical politics on the eve of the civil rights movement.
Prediction of leakage of a pressure-relief valve based on support vector regression with auxiliary input information
Authors: Sun W , Meng G-X , Ye Q , Zhang J-Z
Published: June 2011

It is significant if the gas leakage of pressure-relief valve (PRV) can be accurately predicted in advance, because gas leakage may destroy the PRV's stability and result in a potential damage to the entire pneumatic circuit. This article puts forward a model based on support vector regression (SVR) to predict the gas leakage of PRV. The experimental data of three identical PRVs are employed to evaluate the performance of the leakage prediction model with different input information. The experimental results demonstrate the superiority of the proposed model, proved especially when the pressure difference between inlet and outlet pressures of PRV is chosen as the auxiliary input information. The SVR prediction model which only uses leakage data as input information can perform better than the artificial neural network prediction model, but the prediction accuracy can be further improved if the proper auxiliary input information is taken.
Experimental analysis of unsteady flow performance in an automotive turbocharger turbine fitted with a waste-gate valve
Authors: Capobianco M , Marelli S
Published: June 2011

Downsizing and turbocharging is today an effective way of enhancing fuel economy in automotive engines. However, more information on compressor and turbine behaviour when working under unsteady flow conditions typically occurring in automotive turbocharged engines is still required to improve simulation models.

The results of an experimental investigation into a small turbocharger turbine fitted with a waste-gate valve are presented in this paper. Turbine performance was measured under both steady and unsteady flow operation. Particular attention was given to pulsating flow performance, evaluated starting from the measurement of instantaneous parameters (inlet and outlet static pressure, mass flowrate, and turbocharger rotational speed). The effect of flow unsteadiness on turbine behaviour is analysed, referring to different pulse frequencies and waste-gate settings.

The paper highlights that steady and unsteady turbine performance when the waste-gate valve is partially or totally open should be known in order to improve engine-turbocharger matching calculations.
Non-linear dynamic analysis of automotive suspension system incorporating rubber bump stops
Authors: Azadi Sh , Forouzesh F
Published: June 2011

Rubber bump stops are used in automotive suspension systems to absorb energy, limit the motion of wheels, and reduce vibrations. They are made from elastomeric materials that are non-linear and exhibit large deformation under loading. In the present paper, the bump stop used in a double-wishbone suspension system was analysed numerically to obtain the load–displacement curve and compared with experimental test data. The numerical analysis was done with a non-linear finite element (FE) model using ABAQUS software. The results showed good agreement between numerical and experimental data, with a difference of less than 2 per cent between them. Then dynamic analysis of the suspension system with the bump stop was done to recognize the stress and acceleration effects arising from use of this part in the system. For different vehicle velocities, the comparison between von Mises stress curves in two cases, with and without a bump stop on the lower control arm, showed higher stresses in the lower control arm in the presence of the bump stop and the comparison between acceleration curves showed lower acceleration in the lower control arm with the bump stop. Thus automotive engineers must pay attention to these effects to design suspension components correctly.
Robust clutch slip controller design for automatic transmission
Authors: Liu Z-Y , Gao J-W , Zheng Q
Published: June 2011

To improve the drivability of vehicles with automatic transmissions, a closed-loop turbine speed controller for the inertia phase of the gear shift is designed. Since the system must be robust to the changes in the operating conditions and any deterioration in the automatic transmission fluid (ATF) and the friction material, a robust approach should be used to obtain acceptable performance, even for the worst case. Moreover, as it is known that the change of turbine torque in the inertia phase greatly affects the turbine speed tracking performance, it is important and necessary to suppress the tracking error from the influence of turbine torque. In this paper, based on a linearized model derived from the dynamics of a vehicle powertrain, a two-degree-of-freedom (2DOF) robust proportional–integral–differential (PID) controller is discussed, considering the uncertainties of the proposed model. The estimated turbine torque is used in the feedforward channel to enhance the disturbance rejection performance, while the feedback channel ensures that the system is quadratically stable under various operating conditions and friction characteristics. In this study, MATLAB is utilized as the programming environment, and the powertrain system is analysed in the control-oriented sense. The proposed controller is validated by the simulation of 1–2 upshift.
Investigation of swirl meter performance
Authors: Heim D M , Ghandhi J B
Published: June 2011

The performance of vane- and impulse-type swirl meters was investigated, and a direct calibration method for swirl meters was developed. The zero-swirl bias of the meters was tested by installing an axially aligned tube on the swirl meter. Both the vane- and impulse-type meters showed insignificant zero-swirl bias. A known swirl was provided to the swirl meters using an offset, inclined tube arrangement. The angular momentum flux delivered by this system was found to depend linearly on the product of the offset distance and cosine of the inclination angle. Both the impulse- and vane-type meters were found to give measurements below the known swirl value, but both meters gave results that were linearly dependent on the angular momentum flux, which allows characterization of the meter’s efficiency with a single parameter. The efficiency of the impulse-type meter varied from 0.7 to 0.93, was a moderate function of the flow straightener aspect ratio, and depended slightly on the meter size. The vane-type meter’s efficiency was 0.32–0.45 for the conditions tested, was insensitive to the paddle wheel flow straightener aspect ratio, and depended significantly on the meter size. The vane-type meter measurements were also found to depend on the paddle-to-bore-diameter ratio; values slightly exceeding unity should be used. The swirl meter efficiency can be used to correct measurements to an absolute basis. Based on these findings, a universal correction factor does not exist, and a given measuring device will need to be calibrated using the methodology described.
Preliminary study on a variable-geometry exhaust manifold turbocharging system
Authors: Wang S-M , Zhu J , Deng K-Y , Cui Y , Xing W-D
Published: June 2011

A variable-geometry exhaust manifold (VGEM) turbocharging system can realize a switch between two charging modes by use of a controllable valve, and it can give a good performance at both high-speed operation and low-speed operation. In this paper, a new idea about the VGEM turbocharging system for a six-cylinder diesel engine is proposed, and preliminary experiments on this are carried out. Experiments on the two cases when the controllable valve is closed or is open respectively are performed using two different exhaust manifolds. The steady state experimental results indicate that the turbocharging system works as a pulse turbocharging system and the pulse energy can be utilized fully when the controllable valve is closed at low-speed operation; the turbocharging system works as a semiconstant-pressure turbocharging system and the pumping loss can be reduced fully when the controllable valve is open at high-speed operation. The transient experimental results indicate that the transient performance of the pulse turbocharging system is better than that of the semiconstant-pressure turbocharging system.
Development of artificial dissipation schemes and compressible vorticity confinement methods
Authors: Bagheri-Esfeh H , Malek-Jafarian M
Published: June 2011

The conventional vorticity confinement methods have a constant confinement parameter that should be determined for every problem by trial and error. In this article, vorticity confinement parameters are successfully developed for compressible flows. The first new confinement parameter is proportional to spectral radii of the flux Jacobian matrix. Therefore, the confinement parameter implicitly contains the grid size and the other local fluid properties. In order to gain confidence in the applicability of vorticity confinement, it would be ideal to completely eliminate such constant parameters. In the next part of this article, a suitable relation is introduced for the vorticity confinement parameter that does not need any constant coefficient. The scalar dissipation scheme (SCDS-1) and matrix dissipation scheme (MADS-1) are two common artificial dissipation schemes that have been used for several years. Two new artificial dissipation schemes are introduced by using the QUICK scheme in this article (SCDS-2, MADS-2). The capabilities of these four artificial dissipation schemes are compared for channel flow problem. Then, the new confinement parameters and artificial dissipation schemes are used for solving moving vortex in a uniform flow and supersonic shear layer problems. The methods have been shown to be very effective at treating shock waves and vortex dominant flows.
The use of a constant load to generate equivalent viscoelastic strain in finite element analysis of cemented prosthetic joints subjected to cyclic loading
Authors: Lu Z , McKellop H A
Published: June 2011

Polymers such as polymethyl-methacrylate (PMMA) surgical cement undergo elastic and viscoelastic deformation (creep) in response to physiological cyclic loading. Theoretically, the effect of gradual creep deformation on the stresses, strains, and displacements of a prosthetic joint can be evaluated by running a finite element analysis (FEA) model through a large number of loading cycles. However, with complex (i.e. realistic) models, this approach may require extensive computational time, and may accumulate unacceptably large numerical errors over the many iterations of the model. The present study utilized a Fourier series to represent a periodic stress and incorporated it in the linear viscoelastic constitutive equation. It was demonstrated that, for a linear viscoelastic material, the time average (i.e. the constant in the Fourier series) of the cyclic stress determined the accumulated creep strain and the sinusoidal components of the stress produced the periodic creep strain with a zero average and negligible amplitude. For a geometrically linear FEA model, the solution based on a cyclic stress can be readily applied to an external cyclic load, that is, the creep strain is determined by the time average of the cyclic load. While femoral component models were considered as geometrically non-linear, an FEA model of a femur implanted with an Exeter hip prosthesis showed that there was only a minor difference between the profile of the applied sinusoidal load and that of the resulting displacement. In such cases, applying the time average of a cyclic load to calculate the resulting creep strain with a given duration of loading should expect to provide acceptable accuracy, with a marked reduction in the computational time.