A curve shortening flow rule for closed embedded plane curves with a prescribed rate of change in enclosed area

Motivated by a problem from fluid mechanics, we consider a generalization of the standard curve shortening flow problem for a closed embedded plane curve such that the area enclosed by the curve is forced to decrease at a prescribed rate. Using formal asymptotic and numerical techniques, we derive possible extinction shapes as the curve contracts to a point, dependent on the rate of decreasing area; we find there is a wider class of extinction shapes than for standard curve shortening, for which initially simple closed curves are always asymptotically circular. We also provide numerical evidence that self-intersection is possible for non-convex initial conditions, distinguishing between pinch-off and coalescence of the curve interior.

“Heroic victims”: Discursive constructions of preservice early childhood teacher professional identities

Government policies in Australia and in many other parts of the world, are calling for degree-qualified teachers to work in prior to formal school settings (center-based care, preschool). Yet, many preservice early childhood teachers assume they will end up teaching in primary schools. This paper examines the professional identities preservice early childhood teachers take up and speak into action while participating in classes focused on teaching in child care. Employing poststructural social theory, data drawn from focus groups with preservice early childhood teachers was examined through a Foucauldian-informed discourse analysis. Particular ways in which the preservice teachers talked about images of children and quality in early childhood are scrutinized for how discourses work to constitute the professional identities of preservice early childhood teachers. It was found that the participants drew on a range of competing discourses available to them, through their degree, and from elsewhere to describe the work of teaching young children and teaching in child care. These competing and colliding discourses, it is argued produce an identity of preservice teachers as ‘heroic victims.’ The paper raises questions about the discourses in circulation in preservice early childhood teacher education, and considers the implications this has for professional identities and career pathways—particularly work in child care.

Governing child care in neoliberal times: Discursive constructions of children as economic units and early childhood educators as investment brokers

At any given time in the field of early childhood, there are discourses at play, producing images of children, and these ways of seeing children might be competing, colliding and/or complementing each other. It is fairly widely accepted that in many countries there are versions of dominant discourses that shape and are shaped by current practices in the field of early childhood. These include (1) romantic notions of children running free and connecting with nature and (2) the ‘Bart Simpson’ version of the naughty, cute or savage child, untamed and in need of civilising. These are far from being the only two discursive constructions of children present in current policies and practices. If early childhood professionals are to be active in shaping and implementing policies that affect their work and workforce, it is important that they are aware of the forces at play. In this article, we point to another powerful discourse at play in the Australian context of early childhood education, the image of children as economic units: investments in the future. We show how a ‘moment of arising’ in contemporary policy contexts, dominated by neoliberal principles of reform and competition, has charged early childhood educators in Australia with the duties of a ‘broker’, ensuring that young children are worth the investment. In this article, we begin with (1) a key policy document in early childhood education in Australia and examine the discursive affordances which shape the document. Next, (2) we pinpoint the shifts in how the work of child care is perceived by interrogating this key policy document through a methodology of discursive analysis. We then turn attention (3) to the work of this policy document along with other discourses which directly affect images of children and the shaping role these have on the work of educators. We conclude with (4) a consideration of how the work of early childhood professionals has come to be shaped by this economic discourse, and how they are being required to both work within the policy imperatives and likely to resist this new demand of them.

COMPASS – A tool for evaluation of compression strategies for embedded processors

A major concern of embedded system architects is the design for low power. We address one aspect of the problem in this paper, namely the effect of executable code compression. There are two benefits of code compression – firstly, a reduction in the memory footprint of embedded software, and secondly, potential reduction in memory bus traffic and power consumption. Since decompression has to be performed at run time it is achieved by hardware. We describe a tool called COMPASS which can evaluate a range of strategies for any given set of benchmarks and display compression ratios. Also, given an execution trace, it can compute the effect on bus toggles, and cache misses for a range of compression strategies. The tool is interactive and allows the user to vary a set of parameters, and observe their effect on performance. We describe an implementation of the tool and demonstrate its effectiveness. To the best of our knowledge this is the first tool proposed for such a purpose.

Embedded PZT wafer sensors for structural health monitoring

Recent advances in structural integrity evaluation have led to the development. of PZT wafer sensors (PWAS) which can be embedded or surface mounted for both acoustic emission (AE) and ultrasonic (UT) modes, which forms an integrated approach for Structural Health Monitoring (SHM) of aerospace structures. For the fabrication of PWAS wafers, soft PZT formulation (SP-5H Grade containing dopants like BA, SM, CA, ZN, Y and HF) were used. The piezoelectric charge constant (d(33)) was measured by a d(33) meter. As a first step towards the final objective of developing Health monitoring methods with embedded PWAS, experiments were conducted on aluminum and composite plates of finite dimensions using PWAS sensors. The AE source was simulated by breaking 0.5mm pencil lead on the surface of a thin plate. Experiments were also conducted with surface mounted PZT films and conventional AE sensors in order to establish the sensitivity of PWAS. A comparison of results of theoretical and experimental work shows good agreement.

Size-dependent magnetic properties of iron carbide nanoparticles embedded in a carbon matrix

Here we report on the magnetic properties of iron carbide nanoparticles embedded in a carbon matrix. Granular distributions of nanoparticles in an inert matrix, of potential use in various applications, were prepared by pyrolysis of organic precursors using the thermally assisted chemical vapour deposition method. By varying the precursor concentration and preparation temperature, compositions with varying iron concentration and nanoparticle sizes were made. Powder x-ray diffraction, transmission electron microscopy and Mossbauer spectroscopy studies revealed the nanocrystalline iron carbide (Fe3C) presence in the partially graphitized matrix. The dependence of the magnetic properties on the particle size and temperature (10 K < T < 300 K) were studied using superconducting quantum interference device magnetometry. Based on the affect of surrounding carbon spins, the observed magnetic behaviour of the nanoparticle compositions, such as the temperature dependence of magnetization and coercivity, can be explained.

Eläytymisestä omiin tarinoihin : Televisiosarja katsojien keskustelussa

From sympathetic understanding to own stories. TV-series in the conversation of its viewers. The purpose of this study is to analyze viewers' conversations about TV-series as a practice in which viewers construct meaning to TV-series. In the tradition of British Cultural Studies this study understands that viewer has an active role in interpreting and constructing meaning to TV-series. In the tradition of feminist studies this study understands that gender is being constructed in social and cultural practices. In reception studies, the viewing of TV-series has usually been analyzed as a practice which is embedded at home and in a family. The studies are often based on interviews of viewers, and the analysis of the construction of meaning is based on interview material where the viewers most often talk about their viewing habits and the likes and dislikes of TV-shows and -characters. This study extends the reception and interpretation of TV-series from home to the moments of interaction between viewers. It is quite common to hear how people talk also outside of home about television and the programmes they have watched. In this study the construction of meaning is being studied in viewers' conversations. The method of analysis is conversation analysis which studies the ordered properties of everyday forms of social interaction. The data has been collected in a workplace where four women watched together (and without the presence of a researcher) two TV-series, American sitcom Golden Girls and Finnish family drama Ruusun aika (Time of a Rose), and afterwards had time and chance for discussion. There was neither a questionnaire nor an agenda for the women to discuss. The analysis of the conversation brings up three themes. In the orientation discussions the viewers aim to construct frames in which it makes sense to talk about the TV-series. The frames have mostly to do with the genre of the TV-series. The second theme is concerned with the viewers' aim to achieve sympathetic understanding of the characters in the TV-series. The third theme extends and transfers the conversation about TV-series to real or imaginary stories of own life. In the conversation the reception of a TV-series appears as being in motion: in the orientation discussions the viewers move towards the series, in the character-discussions the viewers move within the world of the series, and when telling their own stories the viewers move away from the TV-series towards their own lives. In the conversations there appears also a distinction in gender-constructions. When the viewers talk about motherhood, they adopt a serious and moralistic tone. When they talk about female sexuality and relationships between women and men they adopt carnevalistic and humorous tone. There are examples of these kinds of gender-constructions also in other studies of Finnish gender culture. Motherhood means the responsibility to good upbringing; relationships with men include something unpredictable and problematic which one handles at best in a humorous way.

Influence lines for bending under a ring load of a free shell, a shell embedded in a soft medium and a shell containing a soft core

Theoretical expressions for stresses and displacements have been derived for bending under a ring load of a free shell, a shell embedded in a soft medium, and a shell containing a soft core. Numerical work has been done for typical cases with an Elliot 803 Digital Computer and influence lines are drawn therefrom.

Roman Ingarden’s Objectivity vs. Subjectivity as a problem of Translatability

Ingarden (1962, 1964) postulates that artworks exist in an “Objective purely intentional” way. According to this view, objectivity and subjectivity are opposed forms of existence, parallel to the opposition between realism and idealism. Using arguments of cognitive science, experimental psychology, and semiotics, this lecture proposes that, particularly in the aesthetic phenomena, realism and idealism are not pure oppositions; rather they are aspects of a single process of cognition in different strata. Furthermore, the concept of realism can be conceived as an empirical extreme of idealism, and the concept of idealism can be conceived as a pre-operative extreme of realism. Both kind of systems of knowledge are mutually associated by a synecdoche, performing major tasks of mental order and categorisation. This contribution suggests that the supposed opposition between objectivity and subjectivity, raises, first of all, a problem of translatability, more than a problem of existential categories. Synecdoche seems to be a very basic transaction of the mind, establishing ontologies (in the more Ingardean way of the term). Wegrzecki (1994, 220) defines ontology as “the central domain of philosophy to which other its parts directly or indirectly refer”. Thus, ontology operates within philosophy as the synecdoche does within language, pointing the sense of the general into the particular and/or viceversa. The many affinities and similarities between different sign systems, like those found across the interrelationships of the arts, are embedded into a transversal, synecdochic intersemiosis. An important question, from this view, is whether Ingardean’s pure objectivities lie basically on the impossibility of translation, therefore being absolute self-referential constructions. In such a case, it would be impossible to translate pure intentionality into something else, like acts or products.

Strategies as Discursive Constructions: The Case of Airline Alliances

In this paper, we argue that by examining the discursive elements in strategy talk we can contribute to our understanding of the myriad of microprocesses and practices that make up strategies. We focus on airline alliances as a particularly illustrative case. Based on a critical discourse analysis of an extensive material of strategy talk on airline alliances, we point to five types of discursive practices that characterize strategizing in this context in 1995–2000: (1) problematization of traditional strategies; (2) rationalization, objectification and factualization of alliance benefits; (3) fixation of ambiguous independence concerns; (4) reframing of cooperation problems as ‘implementation’ issues; and (5) naturalization of alliance strategies. While we want to emphasize the context-specificity of these practices, we claim that similar types of discursive practices are also likely to be an inherent part of strategizing in other settings.

Gender and National Identity Constructions in the Cross-Border Merger Context

In this article we explore ways in which vertical gender inequality is accomplished in discourse in the context of a recent chain of cross-border mergers and acquisitions that resulted in the formation of a multinational Nordic company. We analyse social interactions of ‘doing’ gender in interviews with male senior executives from Denmark, Finland and Sweden. We argue that their explanations for the absence of women in the top echelons of the company serve to distance vertical gender inequality. The main contribution of the article is an analysis of how national identities are discursively (re)constructed in such distancing. New insights are offered to studying gender in multinationals with a cross-cultural team of researchers. Our study sheds light on how gender intersects with nationality in shaping the multinational organization and the identities of male executives in globalizing business.

Image Heritage - The Temporal Dimension in Consumers' Corporate Image Constructions

Images and brands have been topics of great interest in both academia and practice for a long time. The company’s image, which in this study is considered equivalent to the actual corporate brand, has become a strategic issue and one of the company’s most valuable assets. In contrast to mainstream corporate branding research focusing on consumerimages as steered and managed by the company, in the present study a genuine consumer-focus is taken. The question is asked: how do consumers perceive the company, and especially, how are their experiences of the company over time reflected in the corporate image? The findings indicate that consumers’ corporate images can be seen as being constructed through dynamic relational processes based on a multifaceted network of earlier images from multiple sources over time. The essential finding is that corporate images have a heritage. In the thesis, the concept of image heritage is introduced, which stands for the consumer’s earlier company-related experiences from multiple sources over time. In other words, consumers construct their images of the company based on earlier recalled images, perhaps dating back many years in time. Therefore, corporate images have roots - an image heritage – on which the images are constructed in the present. For companies, image heritage is a key for understanding consumers, and thereby also a key for consumer-focused branding strategies and activities. As image heritage is the consumer’s interpretation base and context for image constructions here and now, branding strategies and activities that meet this consumer-reality has a potential to become more effective. This thesis is positioned in the tradition of The Nordic School of Marketing Thought and introduces a relational dynamic perspective into branding through consumers’ image heritage. Anne Rindell is associated to CERS, the Center for Relationship Marketing and Service Management at the Swedish School of Economics and Business Administration.

Studies on design, fabrication and reliability assessment of embedded passives on a high-density interconnect (HDI) organic substrate using a sequential build-up process

One of the foremost design considerations in microelectronics miniaturization is the use of embedded passives which provide practical solution. In a typical circuit, over 80 percent of the electronic components are passives such as resistors, inductors, and capacitors that could take up to almost 50 percent of the entire printed circuit board area. By integrating passive components within the substrate instead of being on the surface, embedded passives reduce the system real estate, eliminate the need for discrete and assembly, enhance electrical performance and reliability, and potentially reduce the overall cost. Moreover, it is lead free. Even with these advantages, embedded passive technology is at a relatively immature stage and more characterization and optimization are needed for practical applications leading to its commercialization.This paper presents an entire process from design and fabrication to electrical characterization and reliability test of embedded passives on multilayered microvia organic substrate. Two test vehicles focusing on resistors and capacitors have been designed and fabricated. Embedded capacitors in this study are made with polymer/ceramic nanocomposite (BaTiO3) material to take advantage of low processing temperature of polymers and relatively high dielectric constant of ceramics and the values of these capacitors range from 50 pF to 1.5 nF with capacitance per area of approximately 1.5 nF/cm(2). Limited high frequency measurement of these capacitors was performed. Furthermore, reliability assessments of thermal shock and temperature humidity tests based on JEDEC standards were carried out. Resistors used in this work have been of three types: 1) carbon ink based polymer thick film (PTF), 2) resistor foils with known sheet resistivities which are laminated to printed wiring board (PWB) during a sequential build-up (SBU) process and 3) thin-film resistor plating by electroless method. Realization of embedded resistors on conventional board-level high-loss epoxy (similar to 0.015 at 1 GHz) and proposed low-loss BCB dielectric (similar to 0.0008 at > 40 GHz) has been explored in this study. Ni-P and Ni-W-P alloys were plated using conventional electroless plating, and NiCr and NiCrAlSi foils were used for the foil transfer process. For the first time, Benzocyclobutene (BCB) has been proposed as a board level dielectric for advanced System-on-Package (SOP) module primarily due to its attractive low-loss (for RF application) and thin film (for high density wiring) properties.Although embedded passives are more reliable by eliminating solder joint interconnects, they also introduce other concerns such as cracks, delamination and component instability. More layers may be needed to accommodate the embedded passives, and various materials within the substrate may cause significant thermo -mechanical stress due to coefficient of thermal expansion (CTE) mismatch. In this work, numerical models of embedded capacitors have been developed to qualitatively examine the effects of process conditions and electrical performance due to thermo-mechanical deformations.Also, a prototype working product with the board level design including features of embedded resistors and capacitors are underway. Preliminary results of these are presented.

Wave propagation analysis in carbon nanotube embedded composite using wavelet based spectral finite elements

In this paper, elastic wave propagation is studied in a nanocomposite reinforced with multiwall carbon nanotubes (CNTs). Analysis is performed on a representative volume element of square cross section. The frequency content of the exciting signal is at the terahertz level. Here, the composite is modeled as a higher order shear deformable beam using layerwise theory, to account for partial shear stress transfer between the CNTs and the matrix. The walls of the multiwall CNTs are considered to be connected throughout their length by distributed springs, whose stiffness is governed by the van der Waals force acting between the walls of nanotubes. The analyses in both the frequency and time domains are done using the wavelet-based spectral finite element method (WSFEM). The method uses the Daubechies wavelet basis approximation in time to reduce the governing PDE to a set of ODEs. These transformed ODEs are solved using a finite element (FE) technique by deriving an exact interpolating function in the transformed domain to obtain the exact dynamic stiffness matrix. Numerical analyses are performed to study the spectrum and dispersion relations for different matrix materials and also for different beam models. The effects of partial shear stress transfer between CNTs and matrix on the frequency response function (FRF) and the time response due to broadband impulse loading are investigated for different matrix materials. The simultaneous existence of four coupled propagating modes in a double-walled CNT-composite is also captured using modulated sinusoidal excitation.

Antimicrobial activity of highly stable silver nano particles embedded in agar-agar matrix as a thin film

Highly stable silver nanoparticles (Ag NPs) in agar-agar (Ag/agar) as inorganic-organic hybrid were obtained as free-standing film by in situ reduction of silver nitrate by ethanol. The antimicrobial activity of Ag/agar film on Escherichia coli (E. coil), Staphylococcus aureus (S. aureus), and Candida albicans (C albicans) was evaluated in a nutrient broth and also in saline solution. In particular, films were repeatedly tested for antimicrobial activity after recycling. UV-vis absorption and TEM studies were carried out on films at different stages and morphological studies on microbes were carried out by SEM. Results showed spherical Ag NPs of size 15-25 nm, having sharp surface plasmon resonance (SPR) band. The antimicrobial activity of Ag/agar film was found to be in the order, C. albicans > E. coil > S. aureus, and antimicrobial activity against C. albicans was almost maintained even after the third cycle. Whereas, in case of E. coil and S. aureus there was a sharp decline in antimicrobial activity after the second cycle. Agglomeration of Ag NPs in Ag/agar film on exposure to microbes was observed by TEM studies. Cytotoxic experiments carried out on HeLa cells showed a threshold Ag NPs concentration of 60 mu g/mL, much higher than the minimum inhibition concentration of Ag NPs (25.8 mu g/mL) for E. coli. The mechanical strength of the film determined by nanoindentation technique showed almost retention of the strength even after repeated cycle. (C) 2010 Elsevier Ltd. All rights reserved.