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81.
In this paper, a process by which experimental, or historical, data are used to create physically meaningful mathematical models is demonstrated. The procedure involves optimising the correlation between this real world data and the mathematical models using a genetic algorithm which is constrained to operate within the physics of the system. This concept is demonstrated here by creating a structural dynamic finite element model for a complete F/A-18 aircraft based on experimental data collected by shaking the aircraft when it is on the ground. The processes used for this problem are easily broken up and solved on a large number of PCs. A technique is described here by which such distributed computing can be carried out using desktop PCs within the secure computing environment of the Defence Science & Technology Organisation without compromising the PC or network security. 相似文献
82.
In this installment of Semantics and Services, we further develop the idea of spatial, temporal, and thematic (STT) processing of semantic Web data and describe the Web infrastructure needed to support it. Starting from Ramesh Jain's vision of the EventWeb as a view of what's possible with a Web that better accommodates all three dimensions of event-related information (thematic, spatial, and temporal), we outline the architecture needed to support it and current research that aims to realize it. 相似文献
83.
Robert L. Wears Shawna J. Perry Stephanie Wilson Julia Galliers James Fone 《Cognition, Technology & Work》2007,9(3):163-170
Large, easily viewed status boards are commonly used in some healthcare settings such as emergency departments, operating
theaters, intensive care units, and inpatient wards. Because these artefacts were developed by front-line users, and have
little to no supervisory or regulatory control, they offer valuable insights into the theories of work and hazard held by
those users. Although the status boards case were locally developed over many years for within-group coordination, they have
also become useful for between-group coordination across organizational boundaries. In this paper, we compare and contrast
the use of such status boards in two disparate settings: a US emergency department, and a UK pediatric ward, and note striking
similarities in their form and usage, despite the large differences in setting. 相似文献
84.
This letter compares two approaches for determining surface reflectance from hyperspectral airborne imagery (HYDICE) radiance values, and discusses the implications for mosaicking multiple flight lines of HYDICE imagery. Empirical line correction, using calibration panels followed by histogram matching to an adjacent image, produced results comparable with that obtained from applying the ATREM model (Gao et al. 1993, Remote Sensing of Environment, 44, 165-178) to the two flight lines individually. Percentage errors were greatest for low albedo materials and for the long wavelength portions of the spectra. Overall, differences in reflectance values between adjacent frames of 2-5% in the visible/near-infrared to more than 25% in the mid-infrared can be expected. 相似文献
85.
Perry Luzwick 《Computer Fraud & Security》2001,2001(7):15-16
There is nothing like doing something right the first time. After all, when do you have time to do it again? So it is with running a business. Do it right the first time and every time. Unfortunately, crackers, phreakers, hacktivists, the competition, and others want to rain on your parade. New and improved products are released. New advertising campaigns attempt to take market share away from you. Those out for a lark, or with malicious intent, break into your computer networks or damage critical infrastructure. To be in crisis mode is not an unusual occurrence. 相似文献
86.
ED Donnenfeld HD Perry A Wallerstein RM Caronia AJ Kanellopoulos PD Sforza G D'Aversa 《Canadian Metallurgical Quarterly》1999,106(1):72-8; discussion 79
PURPOSE: The authors performed a prospective evaluation of the efficacy of treating ocular cicatricial pemphigoid (OCP) with subconjunctival mitomycin C. DESIGN: Unmasked, prospective, internally controlled case series. METHODS: Patients were eligible for treatment with subconjunctival mitomycin C under three criteria: (1) significant complications of systemic immunosuppressant therapy; (2) markedly asymmetric conjunctival disease; and (3) end-stage OCP. All patients received monocular subconjunctival injections of 0.25 ml of 0.2 mg/ml mitomycin C to both the superior and inferior bulbar conjunctivae in the eye with the more severe disease. RESULTS: Nine eyes of nine patients (mean age, 74 years) were treated with subconjunctival mitomycin C to the more-involved eye and were followed for a mean of 23.5 months (range, 12-40 months). Eight of nine patients showed quiescence of their OCP in the treated eye based on serial evaluation of conjunctival cicatrization and grading of conjunctival erythema. Five of the nine untreated eyes showed progression of the conjunctival disease. One patient required concomitant systemic immunosuppressive therapy after subconjunctival mitomycin C. Two patients underwent successful visual rehabilitative surgery in the mitomycin C-treated eye. CONCLUSION: The use of subconjunctival mitomycin C may be effective in preventing progression of conjunctival cicatrization and erythema in patients with OCP. No complications of mitomycin C treatment were noted. Long-term follow-up and further investigation into the efficacy of subconjunctival mitomycin C in the management of OCP is warranted. 相似文献
87.
A Perry N Tarrier R Morriss E McCarthy K Limb 《Canadian Metallurgical Quarterly》1999,318(7177):149-153
OBJECTIVE: To determine the efficacy of teaching patients with bipolar disorder (manic-depressive psychosis) to identify early symptoms of relapse and seek prompt treatment from health services. DESIGN: Single blind randomised controlled trial with matching on four baseline variables using a minimisation algorithm. SETTING: Mental health services in four NHS trusts (one teaching, three non-teaching). SUBJECTS: 69 patients with bipolar disorder who had had a relapse in the previous 12 months. INTERVENTIONS: Seven to 12 individual treatment sessions from a research psychologist plus routine care or routine care alone. MAIN OUTCOME MEASURES: Time to first manic or depressive relapse, number of manic or depressive relapses, and social functioning examined by standardised interviews every six months for 18 months. RESULTS: 25th centile time to first manic relapse in experimental group was 65 weeks compared with 17 weeks in the control group. Event curves of time to first manic relapse significantly differed between experimental and control groups (log rank 7.04, df=1, P=0.008), with significant reductions in the number of manic relapses over 18 months (median difference 30% (95% confidence interval 8% to 52%), P=0.013). The experimental treatment had no effect on time to first relapse or number of relapses with depression, but it significantly improved overall social functioning (mean difference 2.0 (0.7 to 3.2), P=0.003) and employment (mean difference 0.7 (0.1 to 1.3), P=0.030) by 18 months. CONCLUSION: Teaching patients to recognise early symptoms of manic relapse and seek early treatment is associated with important clinical improvements in time to first manic relapse, social functioning, and employment. 相似文献
88.
89.
Oxygen scavengers are commonly used in packaged foods in Japan and much less so in other developed countries, in spite of the advantages that they offer in maintaining quality and extending shelf‐life. The reason stems from the additional cost involved, and even more so because of the lack of sufficient technical information on their performance and the lack of understanding of how to apply them effectively. In the present study the performance of iron‐based oxygen‐scavenging sachets was evaluated. It was found that the actual scavenging capacity is much higher than the ‘nominal’ capacity provided by the manufacturers. Also, a significant distribution in the oxygen absorption capacity exists, even in the same scavenger type. The rate of oxygen scavenging was found to depend on the scavenger type and capacity. It was also found that in an atmosphere containing CO2 (as in MAP applications) the iron‐based oxygen scavengers also absorb CO2. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
90.