912 resultados para Shifted Yangian


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In the present study, films based on linter cellulose and chitosan were prepared using an aqueous solution of sodium hydroxide (NaOH)/thiourea as the solvent system. The dissolution process of cellulose and chitosan in NaOH/thiourea aqueous solution was followed by the partial chain depolymerization of both biopolymers, which facilitates their solubilization. Biobased films with different chitosan/cellulose ratios were then elaborated by a casting method and subsequent solvent evaporation. They were characterized by X-ray analysis, scanning electron microscopy (SEM), atomic force microscopy (AFM), thermal analysis, and tests related to tensile strength and biodegradation properties. The SEM images of the biofilms with 50/50 and 60/40 ratio of chitosan/cellulose showed surfaces more wrinkled than the others. The AFM images indicated that higher the content of chitosan in the biobased composite film, higher is the average roughness value. It was inferred through thermal analysis that the thermal stability was affected by the presence of chitosan in the films; the initial temperature of decomposition was shifted to lower levels in the presence of chitosan. Results from the tests for tensile strength indicated that the blending of cellulose and chitosan improved the mechanical properties of the films and that an increase in chitosan content led to production of films with higher tensile strength and percentage of elongation. The degradation study in a simulated soil showed that the higher the crystallinity, the lower is the biodegradation rate.

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Cu(II) ions previously coordinated with typical electroplating organic additives were investigated as an alternative source of metal for plating bath. The coordination complexes were isolated from reaction between CuSO(4) and organic additives as ligands (oxalate ion, ethylenediamine or imidazole). Deposits over 1010 steel were successfully obtained from electroplated baths using the complexes without any addition of free additives, at pH = 4.5 (H(2)SO(4)/Na(2)SO(4)). These deposits showed better morphologies than deposits obtained from CuSO(4) solution either in the absence or presence of oxalate ion as additive (40 mmol L(-1)), at pH = 4.5 (H(2)SO(4)/Na(2)SO(4))It is suggestive that the starting metal plating coordinated with additives influences the electrode position processes, providing deposits with corrosion potentials shifted over + 200 mV in 0.5 mol L(-1) NaCl (1 mV s(-1)). The resistance against corrosion is sensitive to the type of additive-complex used as precursor. The complex with ethylenediamine presented the best deposit results with the lowest pitting potential (-0.27 V vs 3.0 mol L(-1) CE). It was concluded that the addition of free additives to the electrodeposition baths is not necessary when working with previously coordinated additives. Thus, the complexes generated in ex-situ are good alternatives as plating precursors for electrodeposition bath. (C) 2009 Elsevier B.V. All rights reserved.

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The aim of this work was to evaluate the effect of the storage time on the thermal properties of triethylene glycol dimethacrylate/2,2-bis[4-(2-hydroxy-3-methacryloxy-prop-1-oxy)-phenyl]propane bisphenyl-alpha-glycidyl ether dimethacrylate (TB) copolymers used in formulations of dental resins after photopolymerization. The TB copolymers were prepared by photopolymerization with an Ultrablue IS light-emitting diode, stored in the dark for 160 days at 37 degrees C, and characterized with differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and Fourier transform infrared spectroscopy with attenuated total reflection. DSC curves indicated the presence of an exothermic peak, confirming that the reaction was not completed during the photopolymerization process. This exothermic peak became smaller as a function of the storage time and was shifted at higher temperatures. In DMA studies, a plot of the loss tangent versus the temperature initially showed the presence of two well-defined peaks. The presence of both peaks confirmed the presence of residual monomers that were not converted during the photopolymerization process. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 112: 679-684, 2009

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I consider the case for genuinely anonymous web searching. Big data seems to have it in for privacy. The story is well known, particularly since the dawn of the web. Vastly more personal information, monumental and quotidian, is gathered than in the pre-digital days. Once gathered it can be aggregated and analyzed to produce rich portraits, which in turn permit unnerving prediction of our future behavior. The new information can then be shared widely, limiting prospects and threatening autonomy. How should we respond? Following Nissenbaum (2011) and Brunton and Nissenbaum (2011 and 2013), I will argue that the proposed solutions—consent, anonymity as conventionally practiced, corporate best practices, and law—fail to protect us against routine surveillance of our online behavior. Brunton and Nissenbaum rightly maintain that, given the power imbalance between data holders and data subjects, obfuscation of one’s online activities is justified. Obfuscation works by generating “misleading, false, or ambiguous data with the intention of confusing an adversary or simply adding to the time or cost of separating good data from bad,” thus decreasing the value of the data collected (Brunton and Nissenbaum, 2011). The phenomenon is as old as the hills. Natural selection evidently blundered upon the tactic long ago. Take a savory butterfly whose markings mimic those of a toxic cousin. From the point of view of a would-be predator the data conveyed by the pattern is ambiguous. Is the bug lunch or potential last meal? In the light of the steep costs of a mistake, the savvy predator goes hungry. Online obfuscation works similarly, attempting for instance to disguise the surfer’s identity (Tor) or the nature of her queries (Howe and Nissenbaum 2009). Yet online obfuscation comes with significant social costs. First, it implies free riding. If I’ve installed an effective obfuscating program, I’m enjoying the benefits of an apparently free internet without paying the costs of surveillance, which are shifted entirely onto non-obfuscators. Second, it permits sketchy actors, from child pornographers to fraudsters, to operate with near impunity. Third, online merchants could plausibly claim that, when we shop online, surveillance is the price we pay for convenience. If we don’t like it, we should take our business to the local brick-and-mortar and pay with cash. Brunton and Nissenbaum have not fully addressed the last two costs. Nevertheless, I think the strict defender of online anonymity can meet these objections. Regarding the third, the future doesn’t bode well for offline shopping. Consider music and books. Intrepid shoppers can still find most of what they want in a book or record store. Soon, though, this will probably not be the case. And then there are those who, for perfectly good reasons, are sensitive about doing some of their shopping in person, perhaps because of their weight or sexual tastes. I argue that consumers should not have to pay the price of surveillance every time they want to buy that catchy new hit, that New York Times bestseller, or a sex toy.

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The aim of this essay is to show how Shakespeare’s sonnets violated and reversed the conventional ideas in terms of beauty and idealisation. Furthermore, I will examine the way Shakespeare presented his beloved woman as an absolute opposite of the one created by Petrarch, and how he shifted all the divine metaphors from a woman to a fair young man, creating a new object of praise and admiration.

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IPTV is now offered by several operators in Europe, US and Asia using broadcast video over private IP networks that are isolated from Internet. IPTV services rely ontransmission of live (real-time) video and/or stored video. Video on Demand (VoD)and Time-shifted TV are implemented by IP unicast and Broadcast TV (BTV) and Near video on demand are implemented by IP multicast. IPTV services require QoS guarantees and can tolerate no more than 10-6 packet loss probability, 200 ms delay, and 50 ms jitter. Low delay is essential for satisfactory trick mode performance(pause, resume,fast forward) for VoD, and fast channel change time for BTV. Internet Traffic Engineering (TE) is defined in RFC 3272 and involves both capacity management and traffic management. Capacity management includes capacityplanning, routing control, and resource management. Traffic management includes (1)nodal traffic control functions such as traffic conditioning, queue management, scheduling, and (2) other functions that regulate traffic flow through the network orthat arbitrate access to network resources. An IPTV network architecture includes multiple networks (core network, metronetwork, access network and home network) that connects devices (super head-end, video hub office, video serving office, home gateway, set-top box). Each IP router in the core and metro networks implements some queueing and packet scheduling mechanism at the output link controller. Popular schedulers in IP networks include Priority Queueing (PQ), Class-Based Weighted Fair Queueing (CBWFQ), and Low Latency Queueing (LLQ) which combines PQ and CBWFQ.The thesis analyzes several Packet Scheduling algorithms that can optimize the tradeoff between system capacity and end user performance for the traffic classes. Before in the simulator FIFO,PQ,GPS queueing methods were implemented inside. This thesis aims to implement the LLQ scheduler inside the simulator and to evaluate the performance of these packet schedulers. The simulator is provided by ErnstNordström and Simulator was built in Visual C++ 2008 environmentand tested and analyzed in MatLab 7.0 under windows VISTA.

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When a stationary solar concentrator is designed, the spatial distribution of the available irradiation is of vital interest. An irradiation distribution based only on solar geometry will look similar at different sites. The only difference is that the distribution of the incident irradiation is shifted to lower solar altitudes when latitude is increased. However, real irradiation distribution will show strong asymmetry at high latitude sites, since the winter irradiation is reduced by absorption and scattering in the atmosphere, and by seasonal changes in the climate. The reduced winter irradiation at high latitudes implies that the available annual radiation is concentrated to a narrower angular interval. This means that the degree of concentration that is possible increases with latitude.In the paper examples of irradiation distribution from different sites in Europe from latitude 38°N to 65°N are shown. The origin of the reduced winter irradiation with increased latitude is discussed, and numerical examples on the performance of different types of stationary concentrators for different latitudes are given.

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This thesis deals with the use of inquiry-based approaches in primary school science. The aim is to investigate the goals and purposes that are constituted by the curriculum and by the teachers in interviews and through their teaching in the classroom. The results are used to develop conceptual tools that can be used by teachers’ in their work to support students’ learning of science when using an inquiry-based approach. The thesis is comprised of four papers. In paper one a comparative analysis is made of five Swedish national curricula for compulsory school regarding what students should learn about scientific inquiry. In paper two 20 teachers were interviewed about their own teaching using inquiry. Classroom interactions were filmed and analyzed in papers three and four, which examine how primary teachers use the various activities and purposes of the inquiry classroom to support learning progressions in science. The results of paper one show how the emphasis within and between the two goals of learning to carry out investigations and learning about the nature of science shifted and changed over time in the different curricula. Paper two describes the selective traditions and qualities that were emphasized in the teachers’ accounts of their own teaching. The results of papers three and four show how students need to be involved in the proximate and ultimate purposes of the teaching activities for progression to happen. The ultimate purposes are the scientific purposes for the lesson (as given by the teacher or by the curriculum), whereas the proximate purposes are the more student-centered purposes that through different activities should allow the students to relate their own experiences and language to the ultimate purpose. The results show the importance of proximate purposes working as ends-in-viewin the sense of John Dewey, meaning that the students see the goal of the activity and that they are able to relate to their experiences and familiar language.

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In the past few decades, the demands for coping with the rapid development of information communication technology, internationalization and globalization worldwide have shifted the focus of Chinese as a second language (CSL) towards intercultural communication competence in which the role of culture in the acquisition of CSL and in the pragmatic use of the language is emphasized and promoted. However, most of the present research in this academic area still remains only on a theoretical level.   In order to explore the possibilities and limitations of integrating Chinese culture and implementing intercultural communication theory into CSL education, an action research has been conducted since the beginning of 2013 to review an actual course for beginners. This paper will present the findings of the research: 1) By applying the theoretical framework of intercultural communicative competence, the findings indicated that the existing CSL course provided limited information explaining the cultural elements that are reflected in the Chinese language. 2) The findings also suggested that the cultural skills acquired in the students’ first language do influence their acquisition of CSL. This is demonstrated in the students’ written tasks such as introducing themselves and presenting other people, etc. The findings can be examples and resources for further research in this academic field.     

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I am honored to respond to Paul Guyer’s elaboration on the role of examples of perfectionism in Cavell’s and Kant’s philosophies. Guyer’s appeal to Kant’s notion of freedom opens the way for suggestive readings of Cavell’s work on moral perfectionism but also, as I will show, for controversy. There are salient aspects of both Kant’s and Cavell’s philosophy that are crucial to understanding perfectionism and, let me call it, perfectionist education, that I wish to emphasize in response to Guyer. In responding to Guyer’s text, I shall do three things. First, I shall explain why I think it is misleading to speak of Cavell’s view that moral perfectionism is involved in a struggle to make oneself intelligible to oneself and others in terms of necessary and sufficient conditions for moral perfection. Rather, I will suggest that the constant work on oneself that is at the core of Cavell’s moral perfectionism is a constant work for intelligibility. Second, I shall recall a feature of Cavell’s perfectionism that Guyer does not explicitly speak of: the idea that perfectionism is a theme, “outlook or dimension of thought embodied and developed in a set of texts.” Or, as Cavell goes on to say, “there is a place in mind where good books are in conversation. … [W]hat they often talk about … is how they can be, or sound, so much better than the people that compose them.” This involves what I would call a perfectionist conception of the history of philosophy and the kinds of texts we take to belong to such history. Third, I shall sketch out how the struggle for intelligibility and a perfectionist view of engagement with texts and philosophy can lead to a view of philosophy as a form of education in itself. In concluding these three “criticisms,” I reach a position that I think is quite close to Guyer’s, but with a slightly shifted emphasis on what it means to read Kant and Cavell from a perfectionist point of view.

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Violence at work as a social problem: a study of the media coverage on workplace violence in Swedish trade union journals 1978–2004 The main purpose of this study was to find out the extent of the unions media coverage on workplace violence and the ways in which the topic was framed. The study shows that the reporting of violence in the workplace described in journals is on a stable level during the period 1978–98. However from the year 2000 and onwards, there is a clear increase in the attention. Four categories of workplace violence were used to identify and recognize different types of violence: intrusive-, consumer-, relationship-and organizational violence. This shows that much of the attention over time has shifted from intrusive violence to organizational violence and consumer violence. What seems to have happened is that workplace violence has become more than just robberies and assaults in the retail business. The stereotypical image of the criminal is challenged by non-traditional criminals like nurses, elderly people and companies. Certain groups, e.g. care workers, come to account for an increasing proportion of attention, both as perpetrators and victims of violence. This study is an important step in understanding the increased reports of workplace violence in Sweden.

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In an attempt to find out which of the two Swedish prosodic contrasts of 1) wordstress pattern and 2) tonal word accent category has the greatest communicative weight, a lexical decision experiment was conducted: in one part word stress pattern was changed from trochaic to iambic, and in the other part trochaic accentII words were changed to accent I.Native Swedish listeners were asked to decide whether the distorted words werereal words or ‘non-words’. A clear tendency is that listeners preferred to give more‘non-word’ responses when the stress pattern was shifted, compared to when wordaccent category was shifted. This could have implications for priority of phonological features when teaching Swedish as a second language.

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Bakgrund: Stöd inom abortvård har en stor betydelse för att upprätthålla en professionell förhållningsätt i mötet med patienten i abortsituationen och ge fullgodvård. Syfte: Syftet med den här studien var att beskriva barnmorskors och sjuksköterskors behov av stöd inom abortverksamheten. Metod: Kvalitativa semistrukturerade intervjuer genomfördes med sjuksköterskor och barnmorskor på en svensk kvinnoklinik för att uppnå studiens syfte. Resultat: Resultatet visade att behoven av stöd skiftade, beroende på vårdpersonalens olika utbildningar, arbetslivserfarenheter och personliga egenskaper. Behoven av stöd kunde innefatta kunskap, emotionellt stöd och etisk reflektion. Samspel i vårdteamet som består av gynekologer, barnmorskor, sjuksköterskor och kuratorer var viktigt för att kunna skapa bästa möjliga arbetsmiljö. Förutom grundutbildning som sjuksköterska eller barnmorska skulle behövas mer specifik utbildning inom abortvård.

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Ukraine has repeatedly shifted between the two sub-types of semi-presidentialism, i.e. between premier-presidentialism and president-parliamentarism. The aim of this article is to discuss to what extent theoretical arguments against premier-presidential and president-parliamentary systems are relevant for understanding the shifting directions of the Ukrainian regime. As a point of departure, I formulate three main claims from the literature: 1) “President-parliamentarism is less conducive to democratization than premier-presidentialism.”; 2) “Semi-presidentialism in both its variants have built-in incitements for intra-executive conflict between the president and the prime minister.”; 3) “Semi-presidentialism in general, and president-parliamentarism in particular, encourages presidentialization of political parties.” I conclude from the study’s empirical overview that the president-parliamentary system– the constitutional arrangement with the most dismal record of democratization – has been instrumental in strengthening presidential dominance and authoritarian tendencies. The premier-presidential period 2006–2010 was by no means smooth and stable, but the presidential dominance weakened and the survival of the government was firmly anchored in the parliament. During this period, there were also indications of a gradual strengthening of institutional capacity among the main political parties and the parliament began to emerge as a significant political arena.

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"A newsletter published periodically to keep the faculty, students, staff, and community informed about the activities taking place on the campus of LaGuardia Community College." No date; 2 pages; Color (green, black & white). Cover article: “JOHN WILLIAMS TO HOLD READING DECEMBER 5.” Other entries: “Resolution prohibiting smoking and eating in all classrooms;” “Parking Shifted to L&P;” “Who’s Who Seeks Nominees;” Faculty news; “Cagers to Face John Jay, Ulster.”