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Common Database (common + database)
Selected AbstractsNon-linear approaches for reducing large power systemsEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 3 2001X. Lei Issues on the establishment of equivalent networks are becoming essential for the deregulated power market. This paper presents a comprehensive tool for network reduction of large power systems. Through integrating different methodologies into a simulation program, the dynamic equivalent can be established by adopting one common database. With a readily integrated modified Gauss-Newton algorithm, network reduction can be executed under the dynamic conditions either in the time domain or in the frequency domain in coping with nonlinear nature of the system involved. Furthermore, a novel algorithm based on dynamic coherency approach implemented readily into the simulation program is also presented. This novel approach determines coherent generators on non-linear basis in the time domain using the cross correlation technique, taking dynamic characteristics of the system involved into consideration. Two case studies are presented in this paper. Each of the non-linear approaches presented is applied for one of the case studies as application example. The results achieved validate the functionality of the approaches presented. [source] Development of a historical ice database for the study of climate change in CanadaHYDROLOGICAL PROCESSES, Issue 18 2002Frédéric Lenormand Abstract The Canadian government has been compiling various observations on freshwater and coastal sea ice conditions for many years. However, the records are not easily accessible and are dispersed within different government departments. Given this, a major effort was undertaken in order to gather all available observations into a common database,the Canadian Ice Database (CID). This database will respond to the needs for climate monitoring in Canada, the validation and improvement of numerical ice models and the development of new remote-sensing methods. Indeed, several studies have shown that freshwater ice and sea ice are good proxy indicators of climate variability and change. The first version of CID contains in situ observations from 757 sites distributed across Canada, which were originally kept on digital or paper records at the Meteorological Service of Canada Headquarters and the Canadian Ice Service (CIS). The CID holds 63 546 records covering the period from ice season 1822,23 to 2000,01. An analysis of the database allows one to trace the temporal evolution of the ice networks. The freeze-up/break-up network of 2000,01 only represents 4% of what it was in 1985,86. A drastic decline of the ice thickness and the snow on ice network is also observable. In 1997,98, it represented only 10% of the network that existed in 1984,85. The major budget cuts in Canadian government agencies during the late 1980s and the 1990s offer the most plausible explanation for the drastic decline in the ice observation networks. Weekly ice coverage determination on large lakes from satellite imagery by the CIS and the national volunteer ice monitoring program, IceWatch, may provide a means of reviving, at least, the freeze-up/break-up network. Copyright © 2002 John Wiley & Sons, Ltd. [source] Cloud systems leading to flood events in Europe: an overview and classificationMETEOROLOGICAL APPLICATIONS, Issue 3 2003Federico Porcú Over recent years most European countries have experienced destructive precipitation events, many of which have generated floods resulting in the loss of lives and economic damage. Rather surprisingly, Europe has no common database for flood events, which continue to be monitored by different national and/or local authorities, with different criteria. In the light of this situation, the main aim of the present work is to propose a classification scheme for a European-level flood database, in which severe flood episodes are related to meteorological conditions and mesoscale settings. The meteorological systems relating to the most severe events (22 events) over a five-year period (1992,1996) were analysed using Meteosat imagery and conventional meteorological data. Most of the observed events were related to extra tropical cyclone development. The results are discussed in terms of conceptual models currently used for extra tropical cyclones: the structure and dynamics of Atlantic cyclones can very often be interpreted in terms of well- known conceptual models, while characteristics of Mediterranean systems are not fully rendered by current descriptions. Our study underpins the need to improve the knowledge of Mediterranean systems, possibly introducing new conceptual models and/or refining the current ones. Copyright © 2003 Royal Meteorological Society [source] Evaluation of foliar resistance in potato to Phytophthora infestans based on an international field trial networkPLANT PATHOLOGY, Issue 2 2005J. G. Hansen During the period 2000,03, local potato cultivars in Estonia, Latvia, Lithuania, Poland and Denmark were tested for foliar resistance to Phytophthora infestans (late blight) in an international field trial network. Four standard cultivars were included in the trials: Sava, Oleva, Danva and Kuras. Primary disease-assessment data were entered into a common database, and parameters from the disease progress curves were calculated and made available on interactive web pages. A regression model, using relative area under disease progress curve (RAUDPC) values for cv. Oleva as a reference, was developed for the estimation of 1,9 scale values, where 1 = most susceptible. Standard deviations for the estimated 1,9 scale values and a nonparametric rank stability analysis of RAUDPC were used to evaluate the stability of resistance of the cultivars. Overall, the results showed stability of resistance for cvs Sava, Oleva and Danva, but not for Kuras. Use of the Internet-based Web-Blight service in this study facilitated comparison of results among countries for the level and stability of resistance. The estimated 1,9 scale values were similar to, or slightly lower than, those from official cultivar lists or from the European Cultivated Potato Database, especially for the more resistant cultivars. Possible reasons for discrepancies from different sources and locations are discussed. It is concluded that RAUPDC and the derived 1,9 scale values are useful for ranking cultivars for resistance to P. infestans, but this information is not detailed enough for use in a decision support system for late blight control. [source] Interferon beta-1b treatment in patients with relapsing,remitting multiple sclerosis under a standardized protocol in SpainACTA NEUROLOGICA SCANDINAVICA, Issue 4 2000T. Arbizu Objective, A protocol system is being used in Spain for the prescription of innovative drugs including interferon beta-1b (IFN,-1b). Petitions for dispensing and reimbursement are based on the inclusion and exclusion criteria of pivotal trials, and are reviewed individually for approval by specialist committees. To estimate the performance of IFN,-1b in the clinical setting, data collected by the INSALUD and regional health services of Andalusia and Catalonia, together responsible for the healthcare of nearly 30 million individuals, were compiled in a common database for analysis. Methods, Data comprise demographic and disease characteristics at the time of petition and at follow-up 3 months after treatment initiation and every 6 months thereafter. Efficacy was estimated by mean number of relapses per year, proportion of relapse-free patients, and disease progression as measured by the Expanded Disability Status Scale (EDSS). Safety parameters included adverse events and laboratory analyses. Results, Between September 1995 and database cutoff in mid-1998, petitions of 1419 patients were approved for IFN,-1b treatment. Patients were homogenous across the three databases and in the subgroups of patients completing 1 year (n=940) and 2 years (n=302) of treatment. There was a marked decrease in the mean number of relapses in the first 12 months of IFN,-1b treatment for the 938 patients documented for 12 months, with a mean of 0.4 (±0.7 SD) relapses per patient and year, and a 2-year mean of 0.9 (±1.20 SD) in the 302 patients documented for 24 months. Of the 938 patients followed for ,12 months, 505 (53.8%) were documented as being relapse-free during 12 months of treatment, and 146 (48.3%) of the 302 patients followed for ,24 months, were relapse-free during 24 months of treatment. There were no differences in mean or median EDSS scores between baseline and months 12 and 24. Skin disorders were the most frequent adverse events, reported in over one-third of all patients; there were 159 injection site events, most frequently erythema (115 events). Systemic AEs pointing towards flu-like symptoms were reported in 288 of 1419 patients (20.3%). Leukopenia was the most frequently reported laboratory event. Elevations in liver transaminases were noted for 12 patients (0.8%) with SGOT increase and 7 (0.5%) with SGPT increase. Conclusion, The protocol system has helped make IFN, treatment available to 8,10% of the estimated 15,000,18,000 MS patients in the regions studied. In terms of efficacy, IFN,-1b performed in line with the pivotal study results. The safety profile of IFN,-1b was consistent with the published findings and the drug labelling, and no new side effects or increased incidence of known side effects was observed. [source] Side-effects of allergen-specific immunotherapy.CLINICAL & EXPERIMENTAL ALLERGY, Issue 3 2006A prospective multi-centre study Summary Background and objective The safety of allergen-specific immunotherapy (SIT) is a parameter of great interest in the overall assessment of the treatment. A clinical database was developed in order to obtain early warnings of changes in the frequency and severity of side-effects and sufficient data for the evaluation of possible risk factors. Methods During a 3-year period, four allergy centres in Copenhagen, Denmark, included data from all patients initiating SIT to a common database. Information on initial allergic symptoms, allergens used for treatment, treatment regimens and systemic side-effects (SSEs) during the build-up phase was collected. Results A total of 1038 patients received treatment with 1709 allergens (timothy, birch, mugwort, house dust mite (HDM), cat, and wasp and bee venom), 23 047 injections in total. Most SIT patients completed the updosing phase without side-effects, but there was a significant difference between allergens: wasp (89%), birch (82%), HDM (81%), cat (74%) and grass (70%) (P=0.004). A total of 582 SSEs were registered in 341 patients. Most side-effects were mild grade 2 reactions (78%). A difference in severity between allergens was observed (P=0.02), with grass giving most problems. The type of allergen but not patient- or centre-related parameters seemed predictive of side-effects. Conclusions Allergen extracts differ in their tendency to produce side-effects. Multi-centre studies like the present one allow more patients to be evaluated, and thereby provide a more efficient surveillance of side-effects. Online Internet-based registration to a central national database of every allergen injection would be an even more powerful tool for evaluation of risk factors and surveillance of side-effects. [source] | |||||||||||||