981 resultados para Upper joint space


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This paper explores the concept of social exclusion as it impacts on young people within their local communities and the wider British, European and Australian context in terms of surveillance and other control measures.

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The 2008 NASA Astrobiology Roadmap provides one way of theorising this developing field, a way which has become the normative model for the discipline: science-and scholarship-driven funding for space. By contrast, a novel re-evaluation of funding policies is undertaken in this article to reframe astrobiology, terraforming and associated space travel and research. Textual visualisation, discourse and numeric analytical methods, and value theory are applied to historical data and contemporary sources to re-investigate significant drivers and constraints on the mechanisms of enabling space exploration. Two data sets are identified and compared: the business objectives and outcomes of major 15th-17th century European joint-stock exploration and trading companies and a case study of a current space industry entrepreneur company. Comparison of these analyses suggests that viable funding policy drivers can exist outside the normative science and scholarship-driven roadmap. The two drivers identified in this study are (1) the intrinsic value of space as a territory to be experienced and enjoyed, not just studied, and (2) the instrumental, commercial value of exploiting these experiences by developing infrastructure and retail revenues. Filtering of these results also offers an investment rationale for companies operating in, or about to enter, the space business marketplace.

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As Unmanned Aircraft Systems (UAS) grow in complexity, and their level of autonomy increases|moving away from the concept of a remotely piloted systems and more towards autonomous systems|there is a need to further improve reliability and tolerance to faults. The traditional way to accommodate actuator faults is by using standard control allocation techniques as part of the flight control system. The allocation problem in the presence of faults often requires adding constraints that quantify the maximum capacity of the actuators. This in turn requires on-line numerical optimisation. In this paper, we propose a framework for joint allocation and constrained control scheme via vector input scaling. The actuator configuration is used to map actuator constraints into the space of the aircraft generalised forces, which are the magnitudes demanded by the light controller. Then by constraining the output of controller, we ensure that the allocation function always receive feasible demands. With the proposed framework, the allocation problem does not require numerical optimisation, and since the controller handles the constraints, there is not need to implement heuristics to inform the controller about actuator saturation.

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The Woods Bagot 2007 refurbishment of the Qantas and British Airways Bangkok Business lounge in the Survarnabhumi Airport features wall finishes designed by wallpaper designer, Florence Broadhurst (1899-1977) and Thai Silk trader, Jim Thompson (1906-1967). This distinctive selection, which is proclaimed on the airport’s website, of patterned wall surfaces side by side draws attention to their striking similarities and their defining differences . Thompson and Broadhurst would appear to be worlds apart, but here in the airport their work brings them together. Thompson, the son of a wealthy cotton family in America, worked as an architect before joining the army. He moved to Bangkok to start The Thai Silk Company in 1948. Broadhurst was born on a farm in Mt. Perry, Queensland. She began her career as a performance artist, as part of an Australian troupe in Shanghai, moving onto pursue a career in fashion design, catering to the middle and upper classes in London. Upon her return to Australia, Broadhurst started a print design company in 1959. Both Broadhurst and Thompson pursued multiple careers, lived many lives, and died under mysterious circumstances. Broadhurst was murdered in 1977 at her Sydney print warehouse, which remains an unsolved crime. Thompson disappeared in Malaysia in 1967 and his body has never been found. This chapter investigates the parallels between Thompson and Broadhurst and what lead them to design such popular patterns for wall surfaces towards the end of their careers. While neither designer was a household name, their work is familiar to most, seen in the costume and set design of films, on the walls of restaurants and cafes and even in family homes. The reason for the popularity of their patterns has not previously been analysed. However, this chapter suggests that the patterns are intriguing because they contain something of their designers’ identities. It suggests that the coloured surface provides a way of camouflaging and hiding its subjects’ histories, such that Broadhurst and Thompson, consciously or unconsciously, used the patterned surface as a plane in which their past lives could be buried. The revealing nature of the stark white wall, compared with the forgiveness provided by the pattern in which to hide, is elaborated by painter and advocate for polychromatic architecture, Fernand Léger in his essay, “The Wall, The Architect, The Painter (1965).” Léger writes that, “the modern architect has gone too far in his magnificent attempts to cleanse through emptiness,” and that the resultant white walls of modernity create ‘an impalpability of air, of slick, brilliant new surfaces where nothing can be hidden any longer …even shadows don’t dare to enter’. To counter the exposure produced by the white wall, Thompson and Broadhurst designed patterned surfaces that could harbour their personal histories. Broadhurst and Thompson’s works share a number of commonalities in their design production, even though their work in print design commenced a decade apart. Both designers opted to work more with traditional methods of pattern making. Broadhurst used hand-operated screens, and Thompson outsourced work to local weavers and refrained from operating out of a factory. Despite humble beginnings, Broadhurst and Thompson enjoyed international success with their wall patterns being featured in a number of renowned international hotels in Bahrain, Singapore, Sydney, and London in the 1970s and 1980s. Their patterns were also transferred to fabric for soft furnishings and clothing. Thompson’s patterns were used for costumes in films including the King and I and Ben Hur. Broadhurst’s patterns were also widely used by fashion designers and artists, such as Akira Isogowa‘s costume design for Salome, a 1998 production by the Sydney Dance Company. Most recently her print designs have been used by skin illustrator Emma Hack, in a series of works painting female bodies into Broadhurst’s patterns. Hack’s works camouflage the models’ bodies into the patterned surface, assimilating subject and surface, hinting at there being something living within the patterned wall. More than four decades after Broadhurst’s murder and five decades since Thompson’s disappearance, their print designs persist as more than just a legacy. They are applied as surface finishes with the same fervour as when the designs were first released. This chapter argues that the reason for the ongoing celebration of their work is that there is the impalpable presence of the creator in the patterns. It suggests that the patterns blur the boundary between subject and surface.

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Background: In recent years, there have been investigations concerning upper-limbs kinematics by various devices. The latest generation of smartphones often includes inertial sensors with subunits which can detect inertial kinematics. The use of smartphones is presented as a convenient and portable analysis method for studying kinematics in terms of angular mobility and linear acceleration Objective: The aim of this study was to study humerus kinematics through six physical properties that correspond to angular mobility and acceleration in the three axes of space, obtained by a smartphone. Methods: This cross-sectional study recruited healthy young adult subjects. Descriptive and anthropometric independent variables related to age, gender, weight, size, and BMI were included. Six physical properties were included corresponding to two dependent variables for each of three special axes: mobility angle (degrees) and lineal acceleration (meters/seconds2), which were obtained thought the inertial measurement sensor embedded in the iPhone4 smartphone equipped with three two elements for the detection of kinematic variables: a gyroscope and an accelerometer. Apple uses an LIS302DL accelerometer in the iPhone4. The application used to obtain kinematic data was xSensor Pro, Crossbow Technology, Inc., available at the Apple AppStore. The iPhone4 has storage capacity of 20MB. The data-sampling rate was set to 32 Hz, and the data for each analytical task was transmitted as email for analysis and postprocessing The iPhone4 was placed in the right half of the body of each subject located in the middle third of the humerus slightly posterior snugly secured by a neoprene fixation belt. Tasks were explained concisely and clearly. The beginning and the end were decided by a verbal order by the researcher. Participants were placed standing, starting from neutral position, performing the following analytical tasks: 180º right shoulder abduction (eight repetitions) and, after a break of about 3 minutes, 180º right shoulder flexion (eight repetitions). Both tasks were performed with the elbow extended, wrist in neutral position and the palmar area of the hand toward the midline at the beginning and end of the movement. Results: A total of 11 subjects (8 men, 3 woman) were measured, whose mean of age was 24.7 years (SD = 4.22 years) and their average BMI was 22.64 Kg/m2 (SD = 2.29 Kg/m2). The mean of angular mobility collected by the smartphone was bigger in pitch axis for flexion (= 157.28°, SD= 12.35°) and abduction (= 151.71°, SD= 9.70°). With regard to acceleration, the highest peak mean value was shown in the Y motion axis during flexion (= 19.5°/s2, SD = 0.8°/s2) and abduction (= 19.4°/s2, SD = 0.8°/s2). Also, descriptive graphics of analytical tasks performed were obtained. Conclusions: This study shows how humerus contributes to upper-limb motion and it identified movement patterns. Therefore, it supports smartphone as a useful device to analyze upper-limb kinematics. Thanks to this study it´s possible to develop a simple application that facilitates the evaluation of the patient.

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Several genetic variants are thought to influence white matter (WM) integrity, measured with diffusion tensor imaging (DTI). Voxel based methods can test genetic associations, but heavy multiple comparisons corrections are required to adjust for searching the whole brain and for all genetic variants analyzed. Thus, genetic associations are hard to detect even in large studies. Using a recently developed multi-SNP analysis, we examined the joint predictive power of a group of 18 cholesterol-related single nucleotide polymorphisms (SNPs) on WM integrity, measured by fractional anisotropy. To boost power, we limited the analysis to brain voxels that showed significant associations with total serum cholesterol levels. From this space, we identified two genes with effects that replicated in individual voxel-wise analyses of the whole brain. Multivariate analyses of genetic variants on a reduced anatomical search space may help to identify SNPs with strongest effects on the brain from a broad panel of genes.

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This study analyzes the forming of the occupational identity of the well-educated fixed-term employees. Fixed-term employment contracts amongst the well-educated labour force are exceptionally common in Finland as compared to other European countries. Two groups of modern fixed-term employees are distinguished. The first comprises well-educated women employed in the public sector whose fixed-term employment often consists of successive periods as temporary substitutes. The other group comprises well-educated, upper white-collar men aged over 40, whose fixed-term employment careers often consist of jobs of project nature or posts that are filled for a fixed period only. Method of the study For the empirical data I interviewed 35 persons (26 women and 9 men) in 33 interviews, one of which was conducted by e-mail and one was a group interview. All the interviews were electronically recorded and coded. All the interviewees have two things in common: fixed-term employment and formal high education. Thirteen (13) of them are researchers, four nurses, four midwives, four journalists, and ten project experts. I used the snowball method to get in touch the interviewees. The first interviewees were those who were recommended by the trade unions and by my personal acquaintances. These interviewees, in turn, recommended other potential interviewees. In addition, announcements on the internet pages of the trade unions were used to reach other interviewees. In analysing process I read the research material several times to find the turning points in the narrative the interviewees told. I also searched for the most meaningful stories told and the meaning the interviewees gave to these stories and to the whole narrative. In addition to that I paid attention to co-production of the narrative with the interviewees and analyzed the narrative as performance to be able to search for the preferred identities the interviewees perform. (Riesman 2001, 698-701). I do not pay much attention to the question of truth of a narrative in the sense of its correspondence with facts; rather I think a working life narrative has two tasks: On the one hand one has to tell the facts and on the other hand, he/she has to describe the meaning of these facts to herself/himself. To emphasize the double nature of the narrative about one’s working life I analyzed the empirical data both by categorizing it according to the cultural models of storytelling (heroic story, comedy, irony and tragedy) and by studying the themes most of the interviewees talked about. Ethics of the study I chose to use narrative within qualitative interviews on the grounds that in my opinion is more ethical and more empowering than the more traditional structured interview methods. During the research process I carefully followed the ethical rules of a qualitative research. The purpose of the interviews and the research was told to the interviewees by giving them a written description of the study. Oral permission to use the interview in this research was obtained from the interviewees. The names and places, which are mentioned in the study, are changed to conceal the actual identity of the interviewees. I shared the analysis with the interviewees by sending each of them the first analysis of their personal interview. This way I asked them to make sure that the identity was hidden well enough and hoped to give interviewees a chance to look at their narratives, to instigate new actions and sustain the present one (Smith 2001, 721). Also I hoped to enjoy a new possibility of joint authorship. Main results As a result of the study I introduce six models of telling a story. The four typical western cultural models that guide the telling are: heroic story, comedy, tragedy and satirical story (Hänninen 1999). In addition to these models I found two ways of telling a career filled with fixed-term employments that differ significantly from traditional career story telling. However, the story models in which the interviewees pour their experience locates the fixed term employers work career in an imagined life trajectory and reveals the meaning they give to it. I analyze the many sided heroic story that Liisa tells as an example of the strength of the fear of failing or losing the job the fixed term employee feels. By this structure it is also possible to show that success is felt to be entirely a matter of chance. Tragedy, the failure in one’s trial to get something, is a model I introduce with the help of Vilppu’s story. This narrative gets its meaning both from the sorrow of the failure in the past and the rise of something new the teller has found. Aino tells her story as a comedy. By introducing her narrative, I suggest that the purpose of the comedy, a stronger social consensus, gets deeper and darker shade by fixed-term employment: one who works as a fixed term employee has to take his/her place in his/her work community by him/herself without the support the community gives to those in permanent position. By studying the satiric model Rauno uses, I argue that using irony both turns the power structures to a carnival and builds free space to the teller of the story and to the listener. Irony also helps in building a consensus, mutual understanding, between the teller and the listener and it shows the distance the teller tells to exist between him and others. Irony, however, demands some kind of success in one’s occupational career but also at least a minor disappointment in the progress of it. Helmi tells her story merely as a detective story. By introducing Helmi’s narrative, I argue that this story model strengthens the trust in fairness of the society the teller and the listener share. The analysis also emphasizes the central position of identity work, which is caused by fixed-term employment. Most of the interviewees talked about getting along in working life. I introduced Sari’s narrative as an example of this. In both of these latter narratives one’s personal character and habits are lifted as permanent parts of the actual professional expertise, which in turn varies according to different situations. By introducing these models, I reveal that the fixed-term employees have different strategies to cope with their job situations and these strategies vary according to their personal motives and situations and the actual purpose of the interview. However, I argue that they feel the space between their hopes and fears narrow and unsecure. In the research report I also introduce pieces of the stories – themes – that the interviewees use to build these survival strategies. They use their personal curriculum vitae or portfolio, their position in work community and their work morals to build their professional identity. Professional identity is flexible and varies in time and place, but even then it offers a tool to fix one’s identity work into something. It offers a viewpoint to society and a tool to measure one’s position in surrounding social nets. As one result of the study I analyze the position the fixed-term employees share on the edge of their job communities. I summarize the hopes and fears the interviewees have concerning employers, trade unions, educational institutions and the whole society. In their opinion, the solidarity between people has been weakened by the short-sighted power of the economy. The impact the fixed-term employment has on one’s professional identity and social capital is a many-sided and versatile process. Fixed-term employment both strengthens and weakens the professional identity, social capital and the building of trust. Fixed-term employment also affects one’s day-to-day life by excluding her/him from the norm and by one’s difficulty in making long-term plans (Jokinen 2005). Regardless of the nature of the job contract, the workers themselves are experts in making the best of their sometimes less than satisfying work life and they also build their professional identity by using creatively their education, work experiences and interpersonal relations. However, a long career of short fixed-term employments may seriously change the perception of employee about his/her role. He/she may start concentrating only in coping in his/her unsatisfactory situation and leaves the active improvement of the lousy working conditions to other people. Keywords: narrative, fixed-tem employment, occupational identity, work, story model, social capital, career  

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Doping dependent current-voltage (I-V) and capacitance-voltage (C-V) measurements were carried out on polypyrrole devices in metal-polymer-metal sandwich structure. Temperature dependent I-V measurements infer that space-charge limited conduction (SCLC) with exponential trap distribution is appropriate for the moderately doped samples, whereas trap-free SCLC is observed in lightly doped samples. Trap densities and energies are estimated, the effective mobility is calculated using the Poole-Frenkel model, and the mobility exhibits thermally activated behavior. Frequency dependent capacitance-voltage characteristics show a peak near zero bias voltage, which implies that these devices are symmetric with a negligible barrier height at the metal-polymer interface. Low frequency capacitance measurements have revealed a negative capacitance at higher voltages due to the processes associated with the injection and redistribution of space-charges. (C) 2010 American Institute of Physics.

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It is well known that Alamouti code and, in general, Space-Time Block Codes (STBCs) from complex orthogonal designs (CODs) are single-symbol decodable/symbolby-symbol decodable (SSD) and are obtainable from unitary matrix representations of Clifford algebras. However, SSD codes are obtainable from designs that are not CODs. Recently, two such classes of SSD codes have been studied: (i) Coordinate Interleaved Orthogonal Designs (CIODs) and (ii) Minimum-Decoding-Complexity (MDC) STBCs from Quasi-ODs (QODs). In this paper, we obtain SSD codes with unitary weight matrices (but not CON) from matrix representations of Clifford algebras. Moreover, we derive an upper bound on the rate of SSD codes with unitary weight matrices and show that our codes meet this bound. Also, we present conditions on the signal sets which ensure full-diversity and give expressions for the coding gain.

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Starting from the exact general relativistic expression for the total energy of selfgravitating spherically distributed matter and using the minimum energy priciple, we calculate the upper mass limit for a neutron star to be 3.1 solar masses.

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Coronal holes are the coolest and darkest regions of the upper solar atmosphere, as observed both on the solar disk and above the solar limb. Coronal holes are associated with rapidly expanding open magnetic fields and the acceleration of the high-speed solar wind. During the years of the solar minima, coronal holes are generally confined to the Sun's polar regions, while at solar maxima they can also be found at lower latitudes. Waves, observed via remote sensing and detected in-situ in the wind streams, are most likely responsible for the wind and several theoretical models describe the role of MHD waves in the acceleration of the fast solar wind. This paper reviews the observational evidences of detection of propagating waves in these regions. The characteristics of the waves, like periodicities, amplitude, speed provide input parameters and also act as constraints on theoretical models of coronal heating and solar wind acceleration.

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Transmit antenna selection (AS) is a popular, low hardware complexity technique that improves the performance of an underlay cognitive radio system, in which a secondary transmitter can transmit when the primary is on but under tight constraints on the interference it causes to the primary. The underlay interference constraint fundamentally changes the criterion used to select the antenna because the channel gains to the secondary and primary receivers must be both taken into account. We develop a novel and optimal joint AS and transmit power adaptation policy that minimizes a Chernoff upper bound on the symbol error probability (SEP) at the secondary receiver subject to an average transmit power constraint and an average primary interference constraint. Explicit expressions for the optimal antenna and power are provided in terms of the channel gains to the primary and secondary receivers. The SEP of the optimal policy is at least an order of magnitude lower than that achieved by several ad hoc selection rules proposed in the literature and even the optimal antenna selection rule for the case where the transmit power is either zero or a fixed value.

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Infinite horizon discounted-cost and ergodic-cost risk-sensitive zero-sum stochastic games for controlled Markov chains with countably many states are analyzed. Upper and lower values for these games are established. The existence of value and saddle-point equilibria in the class of Markov strategies is proved for the discounted-cost game. The existence of value and saddle-point equilibria in the class of stationary strategies is proved under the uniform ergodicity condition for the ergodic-cost game. The value of the ergodic-cost game happens to be the product of the inverse of the risk-sensitivity factor and the logarithm of the common Perron-Frobenius eigenvalue of the associated controlled nonlinear kernels. (C) 2013 Elsevier B.V. All rights reserved.

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Using the spatial modulation approach, where only one transmit antenna is active at a time, we propose two transmission schemes for two-way relay channel using physical layer network coding with space time coding using coordinate interleaved orthogonal designs (CIODs). It is shown that using two uncorrelated transmit antennas at the nodes, but using only one RF transmit chain and space-time coding across these antennas can give a better performance without using any extra resources and without increasing the hardware implementation cost and complexity. In the first transmission scheme, two antennas are used only at the relay, adaptive network coding (ANC) is employed at the relay and the relay transmits a CIOD space time block code (STBC). This gives a better performance compared to an existing ANC scheme for two-way relay channel which uses one antenna each at all the three nodes. It is shown that for this scheme at high SNR the average end-to-end symbol error probability (SEP) is upper bounded by twice the SEP of a point-to-point fading channel. In the second transmission scheme, two transmit antennas are used at all the three nodes, CIOD STBCs are transmitted in multiple access and broadcast phases. This scheme provides a diversity order of two for the average end-to-end SEP with an increased decoding complexity of O(M-3) for an arbitrary signal set and O(M-2 root M) for square QAM signal set. Simulation results show that the proposed schemes performs better than the existing ANC schemes under perfect and imperfect channel state information.

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This is a student paper done for a University of California Berkeley Zoology class. Since UCB didn't have its own marine lab at the time, it rented space at Hopkins Marine Station where this work was done. Cadet Hand earned his Ph.D. from Berkeley and went on to become Director of the Bodega Marine Laboratory. Donald Putnam Abbott also earned his Ph.D. from Berkeley and later became a Stanford professor at Hopkins Marine Station. (PDF contains 26 pages)