492 resultados para Long Point Company
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This study resulted in the development of a decision making tool for engineering consultancies looking to diversify into new markets. It reviewed existing decision tools used by contractor's entering new markets to develop a bespoke tool for engineering consultants to establish more rigor around the decision making process rather than rely purely on the intuition of company executives. The tool can be used for developing medium and long term company strategies or as a quick and efficient way to assess the viability of new market opportunities when they arise. A combination of Delphi and Analytical Hierarchy Process was selected as the basis of the decision theory.
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News Corp’s only substantial competitor in the print journalism sector may be on the brink of giving up the ghost, as has long been speculated even by its natural supporters such as Beecher. If it does, hundreds more jobs will go, along with the many hundreds of experienced, skilled journalists and editors already shown the door by the company.
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Work-integrated learning in the form of internships is increasingly important for universities as they seek to compete for students, and seek links with industries. Yet, there is surprisingly little empirical research on the details of internships: (1) What they should accomplish? How they should be structure? (3) How students performance should be assess? There is also surprisingly little conceptual analysis of these key issues, either for business internships in general. or for marketing internships in particular. Furthermore, the "answers" on these issues may differ depending upon the perspective if the three stakeholders: students, business managers and university academics. There is not study in the marketing literature which surveys all three groups on these important aspects of internships. To fill these gaps, this paper discusses and analyses internships goals, internship structure, and internship assessment or undergraduate marketing internships, and then reports on a survey of the views of all three stakeholder groups on these issues. There are a considerable variety of approaches for internships, but generally there is consensus among the stake holder groups, with some notable differences. Managerial implication include recognition of the importance of having and academic aspects in internships; mutual understanding concerning needs and constraints; and the requirement that companies, students, and academics take a long-term view of internship programs to achieve mutually beneficial outcomes.
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The flood flow in urbanised areas constitutes a major hazard to the population and infrastructure as seen during the summer 2010-2011 floods in Queensland (Australia). Flood flows in urban environments have been studied relatively recently, although no study considered the impact of turbulence in the flow. During the 12-13 January 2011 flood of the Brisbane River, some turbulence measurements were conducted in an inundated urban environment in Gardens Point Road next to Brisbane's central business district (CBD) at relatively high frequency (50 Hz). The properties of the sediment flood deposits were characterised and the acoustic Doppler velocimeter unit was calibrated to obtain both instantaneous velocity components and suspended sediment concentration in the same sampling volume with the same temporal resolution. While the flow motion in Gardens Point Road was subcritical, the water elevations and velocities fluctuated with a distinctive period between 50 and 80 s. The low frequency fluctuations were linked with some local topographic effects: i.e, some local choke induced by an upstream constriction between stairwells caused some slow oscillations with a period close to the natural sloshing period of the car park. The instantaneous velocity data were analysed using a triple decomposition, and the same triple decomposition was applied to the water depth, velocity flux, suspended sediment concentration and suspended sediment flux data. The velocity fluctuation data showed a large energy component in the slow fluctuation range. For the first two tests at z = 0.35 m, the turbulence data suggested some isotropy. At z = 0.083 m, on the other hand, the findings indicated some flow anisotropy. The suspended sediment concentration (SSC) data presented a general trend with increasing SSC for decreasing water depth. During a test (T4), some long -period oscillations were observed with a period about 18 minutes. The cause of these oscillations remains unknown to the authors. The last test (T5) took place in very shallow waters and high suspended sediment concentrations. It is suggested that the flow in the car park was disconnected from the main channel. Overall the flow conditions at the sampling sites corresponded to a specific momentum between 0.2 to 0.4 m2 which would be near the upper end of the scale for safe evacuation of individuals in flooded areas. But the authors do not believe the evacuation of individuals in Gardens Point Road would have been safe because of the intense water surges and flow turbulence. More generally any criterion for safe evacuation solely based upon the flow velocity, water depth or specific momentum cannot account for the hazards caused by the flow turbulence, water depth fluctuations and water surges.
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Significant empirical data from the fields of management and business strategy suggest that it is a good idea for a company to make in-house the components and processes underpinning a new technology. Other evidence suggests exactly the opposite, saying that firms would be better off buying components and processes from outside suppliers. One possible explanation for this lack of convergence is that earlier research in this area has overlooked two important aspects of the problem: reputation and trust. To gain insight into how these variables may impact make-buy decisions throughout the innovation process, the Sporas algorithm for measuring reputation was added to an existing agent-based model of how firms interact with each other throughout the development of new technologies. The model�s results suggest that reputation and trust do not play a significant role in the long-term fortunes of an individual firm as it contends with technological change in the marketplace. Accordingly, this model serves as a cue for management researchers to investigate more thoroughly the temporal limitations and contingencies that determine how the trust between firms may affect the R&D process.
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This paper presents a comprehensive study to find the most efficient bitrate requirement to deliver mobile video that optimizes bandwidth, while at the same time maintains good user viewing experience. In the study, forty participants were asked to choose the lowest quality video that would still provide for a comfortable and long-term viewing experience, knowing that higher video quality is more expensive and bandwidth intensive. This paper proposes the lowest pleasing bitrates and corresponding encoding parameters for five different content types: cartoon, movie, music, news and sports. It also explores how the lowest pleasing quality is influenced by content type, image resolution, bitrate, and user gender, prior viewing experience, and preference. In addition, it analyzes the trajectory of users’ progression while selecting the lowest pleasing quality. The findings reveal that the lowest bitrate requirement for a pleasing viewing experience is much higher than that of the lowest acceptable quality. Users’ criteria for the lowest pleasing video quality are related to the video’s content features, as well as its usage purpose and the user’s personal preferences. These findings can provide video providers guidance on what quality they should offer to please mobile users.
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The design of pre-contoured fracture fixation implants (plates and nails) that correctly fit the anatomy of a patient utilises 3D models of long bones with accurate geometric representation. 3D data is usually available from computed tomography (CT) scans of human cadavers that generally represent the above 60 year old age group. Thus, despite the fact that half of the seriously injured population comes from the 30 year age group and below, virtually no data exists from these younger age groups to inform the design of implants that optimally fit patients from these groups. Hence, relevant bone data from these age groups is required. The current gold standard for acquiring such data–CT–involves ionising radiation and cannot be used to scan healthy human volunteers. Magnetic resonance imaging (MRI) has been shown to be a potential alternative in the previous studies conducted using small bones (tarsal bones) and parts of the long bones. However, in order to use MRI effectively for 3D reconstruction of human long bones, further validations using long bones and appropriate reference standards are required. Accurate reconstruction of 3D models from CT or MRI data sets requires an accurate image segmentation method. Currently available sophisticated segmentation methods involve complex programming and mathematics that researchers are not trained to perform. Therefore, an accurate but relatively simple segmentation method is required for segmentation of CT and MRI data. Furthermore, some of the limitations of 1.5T MRI such as very long scanning times and poor contrast in articular regions can potentially be reduced by using higher field 3T MRI imaging. However, a quantification of the signal to noise ratio (SNR) gain at the bone - soft tissue interface should be performed; this is not reported in the literature. As MRI scanning of long bones has very long scanning times, the acquired images are more prone to motion artefacts due to random movements of the subject‟s limbs. One of the artefacts observed is the step artefact that is believed to occur from the random movements of the volunteer during a scan. This needs to be corrected before the models can be used for implant design. As the first aim, this study investigated two segmentation methods: intensity thresholding and Canny edge detection as accurate but simple segmentation methods for segmentation of MRI and CT data. The second aim was to investigate the usability of MRI as a radiation free imaging alternative to CT for reconstruction of 3D models of long bones. The third aim was to use 3T MRI to improve the poor contrast in articular regions and long scanning times of current MRI. The fourth and final aim was to minimise the step artefact using 3D modelling techniques. The segmentation methods were investigated using CT scans of five ovine femora. The single level thresholding was performed using a visually selected threshold level to segment the complete femur. For multilevel thresholding, multiple threshold levels calculated from the threshold selection method were used for the proximal, diaphyseal and distal regions of the femur. Canny edge detection was used by delineating the outer and inner contour of 2D images and then combining them to generate the 3D model. Models generated from these methods were compared to the reference standard generated using the mechanical contact scans of the denuded bone. The second aim was achieved using CT and MRI scans of five ovine femora and segmenting them using the multilevel threshold method. A surface geometric comparison was conducted between CT based, MRI based and reference models. To quantitatively compare the 1.5T images to the 3T MRI images, the right lower limbs of five healthy volunteers were scanned using scanners from the same manufacturer. The images obtained using the identical protocols were compared by means of SNR and contrast to noise ratio (CNR) of muscle, bone marrow and bone. In order to correct the step artefact in the final 3D models, the step was simulated in five ovine femora scanned with a 3T MRI scanner. The step was corrected using the iterative closest point (ICP) algorithm based aligning method. The present study demonstrated that the multi-threshold approach in combination with the threshold selection method can generate 3D models from long bones with an average deviation of 0.18 mm. The same was 0.24 mm of the single threshold method. There was a significant statistical difference between the accuracy of models generated by the two methods. In comparison, the Canny edge detection method generated average deviation of 0.20 mm. MRI based models exhibited 0.23 mm average deviation in comparison to the 0.18 mm average deviation of CT based models. The differences were not statistically significant. 3T MRI improved the contrast in the bone–muscle interfaces of most anatomical regions of femora and tibiae, potentially improving the inaccuracies conferred by poor contrast of the articular regions. Using the robust ICP algorithm to align the 3D surfaces, the step artefact that occurred by the volunteer moving the leg was corrected, generating errors of 0.32 ± 0.02 mm when compared with the reference standard. The study concludes that magnetic resonance imaging, together with simple multilevel thresholding segmentation, is able to produce 3D models of long bones with accurate geometric representations. The method is, therefore, a potential alternative to the current gold standard CT imaging.
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3D models of long bones are being utilised for a number of fields including orthopaedic implant design. Accurate reconstruction of 3D models is of utmost importance to design accurate implants to allow achieving a good alignment between two bone fragments. Thus for this purpose, CT scanners are employed to acquire accurate bone data exposing an individual to a high amount of ionising radiation. Magnetic resonance imaging (MRI) has been shown to be a potential alternative to computed tomography (CT) for scanning of volunteers for 3D reconstruction of long bones, essentially avoiding the high radiation dose from CT. In MRI imaging of long bones, the artefacts due to random movements of the skeletal system create challenges for researchers as they generate inaccuracies in the 3D models generated by using data sets containing such artefacts. One of the defects that have been observed during an initial study is the lateral shift artefact occurring in the reconstructed 3D models. This artefact is believed to result from volunteers moving the leg during two successive scanning stages (the lower limb has to be scanned in at least five stages due to the limited scanning length of the scanner). As this artefact creates inaccuracies in the implants designed using these models, it needs to be corrected before the application of 3D models to implant design. Therefore, this study aimed to correct the lateral shift artefact using 3D modelling techniques. The femora of five ovine hind limbs were scanned with a 3T MRI scanner using a 3D vibe based protocol. The scanning was conducted in two halves, while maintaining a good overlap between them. A lateral shift was generated by moving the limb several millimetres between two scanning stages. The 3D models were reconstructed using a multi threshold segmentation method. The correction of the artefact was achieved by aligning the two halves using the robust iterative closest point (ICP) algorithm, with the help of the overlapping region between the two. The models with the corrected artefact were compared with the reference model generated by CT scanning of the same sample. The results indicate that the correction of the artefact was achieved with an average deviation of 0.32 ± 0.02 mm between the corrected model and the reference model. In comparison, the model obtained from a single MRI scan generated an average error of 0.25 ± 0.02 mm when compared with the reference model. An average deviation of 0.34 ± 0.04 mm was seen when the models generated after the table was moved were compared to the reference models; thus, the movement of the table is also a contributing factor to the motion artefacts.
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Several fringing coral reefs in Moreton Bay, Southeast Queensland, some 300 km south of the Great Barrier Reef (GBR), are set in a relatively high latitude, estuarine environment that is considered marginal for coral growth. Previous work indicated that these marginal reefs, as with many fringing reefs of the inner GBR, ceased accreting in the mid-Holocene. This research presents for the first time data from the subsurface profile of the mid-Holocene fossil reef at Wellington Point comprising U/Th dates of in situ and framework corals, and trace element analysis from the age constrained carbonate fragments. Based on trace element proxies the palaeo-water quality during reef accretion was reconstructed. Results demonstrate that the reef initiated more than 7,000 yr BP during the post glacial transgression, and the initiation progressed to the west as sea level rose. In situ micro-atolls indicate that sea level was at least 1 m above present mean sea level by 6,680 years ago. The reef remained in "catch-up" mode, with a seaward sloping upper surface, until it stopped aggrading abruptly at ca 6,000 yr BP; no lateral progradation occurred. Changes in sediment composition encountered in the cores suggest that after the laterite substrate was covered by the reef, most of the sediment was produced by the carbonate factory with minimal terrigenous influence. Rare earth element, Y and Ba proxies indicate that water quality during reef accretion was similar to oceanic waters, considered suitable for coral growth. A slight decline in water quality on the basis of increased Ba in the later stages of growth may be related to increased riverine input and partial closing up of the bay due to either tidal delta progradation, climatic change and/or slight sea level fall. The age data suggest that termination of reef growth coincided with a slight lowering of sea level, activation of ENSO and consequent increase in seasonality, lowering of temperatures and the constrictions to oceanic flushing. At the cessation of reef accretion the environmental conditions in the western Moreton Bay were changing from open marine to estuarine. The living coral community appears to be similar to the fossil community, but without the branching Acropora spp. that were more common in the fossil reef. In this marginal setting coral growth periods do not always correspond to periods of reef accretion due to insufficient coral abundance. Due to several environmental constraints modern coral growth is insufficient for reef growth. Based on these findings Moreton Bay may be unsuitable as a long term coral refuge for most species currently living in the GBR.
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Background Foot ulcers are a leading cause of diabetes-related hospitalisations. Clinical training has been shown to be beneficial in foot ulcer management. Recently, improved self-confidence in podiatrists was reported immediately after foot ulcer simulation training (FUST) pilot programs. This study aimed to investigate the longer-term impacts of the FUST program on podiatrists’ self-confidence over 12 months in a larger sample. Methods Participants were podiatrists attending a two-day FUST course comprising web-based interactive learning, low-fidelity part-tasks and high-fidelity full clinical scenarios. Primary outcome measures included participants’ self-confidence measured pre-, (immediately) post-, 6-month post- and 12-month post-course via a purpose designed 21-item survey using a five-point Likert scale (1=Very limited, 5=Highly confident). Participants’ perceptions of knowledge gained, satisfaction, relevance and fidelity were also investigated. ANOVA and post hoc tests were used to test any differences between groups. Results Thirty-four participants completed FUST. Survey response rates were 100% (pre), 82% (post), 74% (6-month post), and 47% (12-month post). Overall mean scores were 3.13 (pre), 4.49 (post), 4.35 (6-month post) and 4.30 (12-month post) (p < 0.05); post hoc tests indicated no differences between the immediately, 6-month and 12-month post group scores (p > 0.05). Satisfaction, knowledge, relevance and fidelity were all rated highly. Conclusion This study suggests that significant short-term improvements in self-confidence to manage foot ulcers via simulation training are retained over the longer term. It is likely that improved self-confidence leads to improved foot ulcer clinical practice and outcomes; although this requires further research.
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The producer has for many years been a central agent in recording studio sessions; the validation of this role was, in many ways, related to the producer’s physical presence in the studio, to a greater or lesser extent. However, improvements in the speed of digital networks have allowed studio sessions to be produced long-distance, in real-time, through communication programs such as Skype or REDIS. How does this impact on the role of the producer, a “nexus between the creative inspiration of the artist, the technology of the recording studio, and the commercial aspirations of the record company” (Howlett 2012)? From observations of a studio recording session in Lisbon produced through Skype from New York, this article focuses on the role of the producer in these relatively new recording contexts involving long distance media networks. Methodology involved participant observation carried out in Estúdios Namouche in Lisbon (where the session took place), as part of doctoral research. This ethnographic approach also included a number of semi-directed ethnographic interviews of the different actors in this scenario—musicians, recording engineers, composers and producers. As a theoretical framework, the research of De Zutter and Sawyer on Distributed Creativity is used, as the recording studio sets an example of “a cognitive system where […] tasks are not accomplished by separate individuals, but rather through the interactions of those individuals” (DeZutter 2009:4). Therefore, creativity often emerges as a result of this interaction.
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This paper evaluates the performances of prediction intervals generated from alternative time series models, in the context of tourism forecasting. The forecasting methods considered include the autoregressive (AR) model, the AR model using the bias-corrected bootstrap, seasonal ARIMA models, innovations state space models for exponential smoothing, and Harvey’s structural time series models. We use thirteen monthly time series for the number of tourist arrivals to Hong Kong and Australia. The mean coverage rates and widths of the alternative prediction intervals are evaluated in an empirical setting. It is found that all models produce satisfactory prediction intervals, except for the autoregressive model. In particular, those based on the biascorrected bootstrap perform best in general, providing tight intervals with accurate coverage rates, especially when the forecast horizon is long.
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Aortic root replacement is a complex procedure, though subsequent modifications of the original Bentall procedure have made surgery more reproducible. The study aim was to examine the outcomes of a modified Bentall procedure, using the Medtronic Open PivotTM valved conduit. Whilst short-term data on the conduit and long-term data on the valve itself are available, little is known of the long-term results with the valved conduit. Patients undergoing aortic root replacement between February 1999 and February 2010, using the Medtronic Open Pivot valved conduit were identified from the prospectively collected Cardiothoracic Register at The Prince Charles Hospital, Brisbane, Australia. All patients were followed up echocardiographically and clinically. The primary end-point was death, and a Cox proportional model was used to identify factors associated.with survival. Secondary end-points were valve-related morbidity (as defined by STS guidelines) and postoperative morbidity. Predictors of morbidity were identified using logistic regression. A total of 246 patients (mean age 50 years) was included in the study. The overall mortality was 12%, with actuarial 10-year survival 79% and a 10-year estimate of valve-related death of 0.04 (95% CI: 0.004, 0.07). Preoperative myocardial infarction (p = 0.004, HR 4.74), urgency of operation (p = 0.038, HR 2.8) and 10% incremental decreases in ejection fraction (p = 0.046, HR 0.69) were predictive of mortality. Survival was also affected by the valve gradients, with a unit increase in peak gradient reducing mortality (p = 0.021, HR 0.93). Valve-related morbidity occurred in 11 patients. Urgent surgery (p <0.001, OR 4.12), aortic dissection (p = 0.015, OR 3.35), calcific aortic stenosis (p = 0.016, OR 2.35) and Marfan syndrome (p 0.009, OR 3.75) were predictive of postoperative morbidity. The reoperation rate was 1.2%. The Medtronic Open Pivot valved conduit is a safe and durable option for aortic root replacement, and is associated with low morbidity and 10-year survival of 79%. However, further studies are required to determine the effect of valve gradient on survival.
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The 12.7-10.5 Ma Cougar Point Tuff in southern Idaho, USA, consists of 10 large-volume (>10²-10³ km³ each), high-temperature (800-1000 °C), rhyolitic ash-flow tuffs erupted from the Bruneau-Jarbidge volcanic center of the Yellowstone hotspot. These tuffs provide evidence for compositional and thermal zonation in pre-eruptive rhyolite magma, and suggest the presence of a long-lived reservoir that was tapped by numerous large explosive eruptions. Pyroxene compositions exhibit discrete compositional modes with respect to Fe and Mg that define a linear spectrum punctuated by conspicuous gaps. Airfall glass compositions also cluster into modes, and the presence of multiple modes indicates tapping of different magma volumes during early phases of eruption. Equilibrium assemblages of pigeonite and augite are used to reconstruct compositional and thermal gradients in the pre-eruptive reservoir. The recurrence of identical compositional modes and of mineral pairs equilibrated at high temperatures in successive eruptive units is consistent with the persistence of their respective liquids in the magma reservoir. Recurrence intervals of identical modes range from 0.3 to 0.9 Myr and suggest possible magma residence times of similar duration. Eruption ages, magma temperatures, Nd isotopes, and pyroxene and glass compositions are consistent with a long-lived, dynamically evolving magma reservoir that was chemically and thermally zoned and composed of multiple discrete magma volumes.