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Arcadia, CA, United States

Savage G.,Operation Center
Engineering Failure Analysis | Year: 2010

Since the early 1990s the design and operation of Formula 1 racing cars has moved from the traditional empirical approach to one which is far more numerical, particularly with the introduction of finite element stress analysis codes, computer simulation, control and monitoring systems. The difference between the quickest and slowest cars on an F1 circuit is around 1.5. s in an average lap time of 80-90. s, only 1.2%. In the level below (GP2) the difference is 4-6% yet they all have essentially the same car! The sport has therefore developed into a " technology war" as the teams search for the " unfair advantage" with which to defeat their opponents. Much of the chassis technology is derived from or similar to that in the aerospace industry due to their similarity of purpose, their designs being both weight and stiffness critical. Approximately 80% of the testing of a modern Formula 1 car takes place in the laboratory either on test rigs or virtually via computer simulation. The pace of development within the sport is breathtaking; if a car were to win the first race and not be upgraded, by the end of the season it would not only be last, it would be lapped! The car which is last on the grid at the first race of a new season would be of adequate performance to have been on pole position and won the last race of the previous season. Although the performance difference between the whole grid is only 1.2%, we must add on average 1% of performance per race just to stand still. This is best summed up in a single statement; " If I would have had this year's car last year I would have won every race!" Successful teams must therefore embrace the very latest technology and use it in highly stressed situations. Driven by the intense pressure of competition, our ability to build and operate systems sometimes runs in advance of our ability to fully understand them. We operate a " zero defects" total quality management (TQM) process throughout the team, enabling full traceability from raw materials through to obsolescence using our ERP. Parts are required to be managed and conformance guaranteed throughout their life wherever they are in the world and under whatever service conditions. Processes and procedures are put in place which to the best of our skill and ability, prevent failure. Sometimes however things do go wrong. Under such circumstances there must be a robust process which is quickly implemented to solve the problem and affect a solution. This process will be illustrated with worked examples. © 2009 Elsevier Ltd. Source

Sutterlin M.,University of Bern | Schaaf C.B.,University of Massachusetts Boston | Schaaf C.B.,Boston University | Stockli R.,Operation Center | And 5 more authors.
Remote Sensing of Environment | Year: 2015

In this study, the land surface albedo together with its Bidirectional Reflectance Distribution Function (BRDF) are retrieved for the years 2000 to 2012 from Local Area Coverage (LAC) surface reflectance data gathered by the Advanced Very High Resolution Radiometer (AVHRR) over Europe. For the retrieval the MODerate resolution Imaging Spectroradiometer (MODIS) BRDF/albedo processing scheme is employed. The comparatively high revisit frequency and high variability in angular sampling of the AVHRR sensors operated simultaneously onboard the different National Oceanic and Atmospheric Administration (NOAA) and Meteorological Operational (MetOp) satellites contribute substantially to the success and quality of BRDF retrieval. The performance of the BRDF model for AVHRR data is assessed by comparison to MODIS BRDF retrievals, and the AVHRR BRDF reflectance data is validated against BRDF reflectance data from MODIS and in situ data gathered at three field sites in Switzerland. The comparison shows that the AVHRR BRDF retrievals are of high quality across most of Europe. The higher angular sampling of AVHRR allows for more full model retrievals of best quality and generates less fill values compared to MODIS. For most of the years investigated, the absolute accuracy of the AVHRR albedos is found to be within 0.05 throughout the complete seasonal cycle with a minimum bias at the peak of the growing season. However, they systematically underestimate the field-measured albedos, predominantly in winter due to spatial scale mismatch in combination with site heterogeneity and because the expression for the calculation of satellite-based blue-sky albedo does not account for multiple scattering. A slightly increased underestimation also occurs during vegetation senescence, presumably because of the narrow to broadband conversion employing only two bands. Overall, the results confirm the potential of AVHRR to produce multi-decadal data sets of reflectance anisotropy and albedo for use in climate monitoring and modeling studies. This offers a promising and unique opportunity to produce a BRDF/albedo climate data record from AVHRR dating back to 1985. © 2015 Elsevier Inc. Source

Bhend J.,CSIRO | Bhend J.,Operation Center | Whetton P.,CSIRO
Australian Meteorological and Oceanographic Journal | Year: 2015

The ability to reproduce recent observed climate change in climate models is a pertinent prerequisite for trust in climate projections. Also, information on the consistency of simulated and observed recent changes helps users to interpret near-term climate change projections. A comprehensive assessment of simulated regional trends, however, is often not available. Therefore, we evaluate daily maximum and minimum temperature trends and rainfall trends from 1956-2005 in Australia in simulations from the CMIP5 archive. For all variables and all models, we find significant (at the 10% level) differences between simulated and observed trends in some areas. Except for daily minimum temperature in spring and summer, however, the areas where we find significant differences are smaller than what we expect by chance. In a multivariate evaluation, simulated joint temperature and rainfall trends of all but one model, however, are found to be significantly (at the 10% level) different from the observed trends. Hence, multivariate evaluation provides a stricter test. We conclude that CMIP5 models share trend biases and regional projections therefore have to account for the presence of biases shared across models. Source

Fukuhara H.,Kochi Medical School | Inoue K.,Kochi Medical School | Satake H.,Kochi Medical School | Tamura K.,Kochi Medical School | And 6 more authors.
International Journal of Urology | Year: 2011

Objectives: To investigate the feasibility of intraoperative photodynamic diagnosis (PDD) by 5-aminolevulinic acid (ALA) for the identification of positive surgical margins (PSM) during retropubic radical prostatectomy (RRP) in patients with prostate cancer (PCa). Methods: Intraoperative PDD was carried out in 16 patients with pathologically confirmed PCa by biopsy of the apex, or carrying >25% of probability of extraprostatic extension as defined by Japan PC Table. Before operation, 1.0g of ALA was given orally. During open RRP, the resection margins inside the body were examined by PDD system with a fluorescence laparoscope. After their removal, 12 harvested prostates were divided and also investigated by PDD. Red fluorescent-positive lesions were biopsied and compared with the pathological result. Results: All 16 patients were fluorescence-negative inside the body, and negative margins were pathologically confirmed during PDD. Among the 43 specimens of 12 cases obtained by biopsy under PDD, 11 specimens (25.6%) were pathologically diagnosed as malignant tissue (adenocarcinoma, 10 specimens; high grade prostatic intraepithelial neoplasia, 1 specimen) and 19 specimens (44.2%) were evaluated as positive fluorescence by PDD with a sensitivity of 81.8%, a specificity of 68.8% and a predictive accuracy of 72.1%. No side-effects were observed and the procedures were well tolerated. Conclusions: PDD mediated by ALA during RRP might be a feasible and safe modality for detection of surgical margins. Further prospective randomized studies with larger populations are required. © 2011 The Japanese Urological Association. Source

Wan J.,Operation Center | Zhu L.,Clinic Laboratory of Organ Transplantation Center | Cheng K.,Central South University
Urologia Internationalis | Year: 2013

Background: Circulating cell-free DNA (cfDNA) mostly originates from tumors and its level correlates with treatment. We assessed whether the level of plasma cfDNA could help monitor recurrence after nephrectomy. Methods: This study included 92 patients with clear cell renal cell carcinoma (cRCC). Quantitative real-time PCR was used to measure the level of plasma cfDNA before and after nephrectomy. Results: The pretreatment level of plasma cfDNA in patients with metastatic cRCC (6.04 ± 0.72) was significantly higher than in those with localized cRCC (5.29 ± 0.53, p = 0.017) or controls (0.65 ± 0.29, p < 0.001). Of patients with localized cRCC, those with recurrence had a significantly higher plasma cfDNA level than those without (p = 0.024). The patients with a high plasma cfDNA level had a significantly higher recurrence rate than those with a low plasma cfDNA level before and after nephrectomy (p = 0.018). Conclusion: The level of plasma cfDNA may be useful as a tool to monitor patients during follow-up and guide further diagnostic work-up for the detection of recurrence. © 2013 S. Karger AG, Basel. Source

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