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991.
992.
The so-called General Adaptive Neighborhood Image Processing (GANIP) approach is presented in a two parts paper dealing respectively
with its theoretical and practical aspects.
The Adaptive Neighborhood (AN) paradigm allows the building of new image processing transformations using context-dependent
analysis. Such operators are no longer spatially invariant, but vary over the whole image with ANs as adaptive operational
windows, taking intrinsically into account the local image features. This AN concept is here largely extended, using well-defined mathematical concepts,
to that General Adaptive Neighborhood (GAN) in two main ways. Firstly, an analyzing criterion is added within the definition of the ANs in order to consider the radiometric, morphological or geometrical characteristics
of the image, allowing a more significant spatial analysis to be addressed. Secondly, general linear image processing frameworks are introduced in the GAN approach, using concepts of abstract linear algebra, so as to develop operators that
are consistent with the physical and/or physiological settings of the image to be processed. 相似文献
993.
Johan Vessby Bertil Enquist Hans Petersson Tomas Alsmarker 《Holz als Roh- und Werkstoff》2009,67(2):211-218
The use of cross-laminated structural timber elements is becoming increasingly popular. The number of layers varies normally from three upwards. The structural performance of five-layer cross-laminated timber elements was investigated. The five layers consisted of 19 mm thick boards, laid successively at right angles to each other and glued together with PU-adhesive, layers 1, 3 and 5 lying in one direction and layers 2 and 4 in the other. The stiffness and strength of four cross-laminated timber elements (4955 mm long, 1250 mm wide and 96 mm thick) were studied during in-plane bending. Two of the elements were first partitioned into two parts that were reconnected in two different ways prior to testing. The influence of the way in which the cross-laminated timber elements were reconnected was studied, the behaviour observed being compared with the test results for the unpartitioned specimens with respect to both strength and stiffness. The experimental tests performed showed the cross-laminated timber elements to possess a high degree of stiffness and strength. There was also found to be a marked difference in behaviour between the two different ways in which the elements were connected to each other. One of the two connecting methods studied, being of less good design but earlier frequently used in Sweden, showed as expected poor structural performance, whereas the other one applied as a safer alternative performed well. 相似文献
994.
995.
Development and evaluation of the Balanced Index of Psychological Mindedness (BIPM). 总被引:1,自引:0,他引:1
Psychological mindedness (PM) refers to a person's interest and ability to be in touch with and reflect on his or her psychological states and processes. In this multipart study, the authors present the Balanced Index of Psychological Mindedness (BIPM). The psychometric properties and clinical relevance of this 14-item self-report scale were examined in 2 community samples and a mental health patient sample in the Netherlands (total N = 1,211). The 7-item Interest and Insight subscales of the BIPM showed good internal consistency (Cronbach's αs = .85 and .76, respectively), test–retest reliability (r = .63 and .71, respectively), and construct validity (e.g., r > .40 with related constructs). PM was higher in women than in men. Relatively low PM was found among poorly educated people and in mental health patients (ps r = ?.21 to ?.36, p 相似文献
996.
Comparison of sodium and lead-cooled fast reactors regarding reactor physics aspects, severe safety and economical issues 总被引:2,自引:1,他引:1
A large number of new fast reactors may be needed earlier than foreseen in the Generation IV plans. According to the median forecast of the Special Report on Emission Scenarios commissioned by the Intergovernmental Panel on Climate Control nuclear power will increase by a factor of four by 2050. The drivers for this expected boost are the increasing energy demand in developing countries, energy security, but also climate concerns. However, staying with a once-through cycle will lead to both a substantially increased amount of high-level nuclear waste and an upward pressure on the price of uranium and even concerns about its availability in the coming decades. Therefore, it appears wise to accelerate the development of fast reactors and efficient re-processing technologies.In this paper, two fast reactor systems are discussed—the sodium-cooled fast reactor, which has already been built and can be further improved, and the lead-cooled fast reactor that could be developed relatively soon. An accelerated development of the latter is possible due to the sizeable experience on lead/bismuth eutectic coolant in Russian Alpha-class submarine reactors and the research efforts on accelerator-driven systems in the EU and other countries.First, comparative calculations on critical masses, fissile enrichments and burn-up swings of mid-sized SFRs and LFRs (600 MWe) are presented. Monte Carlo transport and burn-up codes were used in the analyses. Moreover, Doppler and coolant temperature and axial fuel expansion reactivity coefficients were also evaluated with MCNP and subsequently used in the European Accident Code-2 to calculate reactivity transients and unprotected Loss-of-Flow (ULOF) and Loss-of-Heat Sink (ULOHS) accidents. Further, ULOFs as well as decay heat removal (protected Total Loss-of-Power, TLOP) were calculated with the STAR-CD CFD code for both systems.We show that LFRs and SFRs can be used both as burners and as self-breeders, homogeneously incinerating minor actinides. The tight pin lattice SFRs (P/D = 1.2) appears to have a better neutron economy than wide channel LFRs (P/D = 1.6), resulting in larger BOL actinide inventories and lower burn-up swings for LFRs. The reactivity burn-up swing of an LFR self-breeder employing BeO moderator pins could be limited to 1.3$ in 1 year. For a 600 MWe LFR burner, LWR-to-burner support ratio was about two for (U, TRU)O2-fuelled system, while it increased to approximately 2.8 when (Th, TRU)O2 fuel was employed. The corresponding figures for an SFR were somewhat lower. The calculations revealed that LFRs have an advantage over SFRs in coping with the investigated severe accident initiators (ULOF, ULOHS, TLOP). The reason is better natural circulation behavior of LFR systems and the much higher boiling temperature of lead. A ULOF accident in an LFR only leads to a 220 K coolant outlet temperature increase whereas for an SFR the coolant may boil. Regarding the economics, the LFR seems to have an advantage since it does not require an intermediate coolant circuit. However, it was also proposed to avoid an intermediate coolant circuit in an SFR by using a supercritical CO2 Brayton cycle. But in an LFR, the reduced concern about air and water ingress may decrease its cost further. 相似文献
997.
Johan Moulin Marion Woytasik Jean-Paul Grandchamp Elisabeth Dufour-Gergam Alain Bosseboeuf 《Microsystem Technologies》2007,13(11-12):1553-1558
Copper planar microcoils were processed by U.V. lithography on SiO2/Si and Kapton®. They were packaged on different types of support in order to study the influence of thermal exchange conditions on device functioning. An electric current was injected in the coil and step by step increased until the electric connection broke, while the temperature of the microcoils remained free. This latter was estimated from the copper resistivity. It allowed demonstrating that the thermal exchange mode of the wire-bonded microcoils is conductive. The current density was calculated taking into account the deterioration of the coils by oxidation. Its maximum value is linearly decreasing with the thermal exchange ability of the support. The failure modes of the microcoils are related to track melting and oxidation, the current density remaining one order too weak to induce electromigration. 相似文献
998.
Solar radiation is characterized by short fluctuations introduced by passing clouds. An analysis of these fluctuations with regard to solar energy applications should focus on the instantaneous clearness index. Its probability distribution for a given mean clearness index is, as a first approximation, independent from the season and partly also from the site. This is verified for four annual datasets from three different sites.An analysis of fluctuations in solar radiation must focus on their amplitude, persistence, and frequency of occurrence rather than their location in time. The Fourier analysis cannot satisfactorily provide this information since time series of the instantaneous clearness index exhibit no periodicity. Instead, a localized spectral analysis based on wavelet bases rather than on periodic-ones has been applied. This analysis allows the decomposition of the fluctuating clearness index signal into a set of orthonormal subsignals. Each of them represents one specific scale of persistence of the fluctuation.The annual mean square values of all subsignals have been analysed, permitting the allocation of the signal’s power content to the different scales of persistence of a fluctuation. These annual mean values agree well for the different datasets, indicating the existence of statistically significant mean square values of the fluctuations as a function of their persistence.The analysis offers a valuable tool for the estimation of power flow fluctuations introduced by direct solar energy systems. With further elaboration it may be applied by power system operators for network planning in distribution grids with a high density of embedded generation. 相似文献
999.
1000.
J. Suykens Ph. Lemmerling W. Favoreel B. de Moor M. Crepel P. Briol 《Neural Processing Letters》1996,4(3):157-166
In this paper an accurate neural network model is proposed for the gas consumption in Belgium. It is a static non-linear model, based on monthly data and contains the following inputs: temperature, difference between real and expected temperature, oil price, number of domestic clients and consumption by industry. Various interpretations are made on the identified models such as yearly error, normalized gas consumption, growth rate, uncertain linear model interpretation and sensitivity of the consumption with respect to the temperature. In contrast to traditional models, which depend only on the temperature, the present neural network models show excellent generalization ability, with small yearly errors on training and test set.This research work was carried out at the ESAT laboratory and the Interdisciplinary Center of Neural Networks, ICNN, of the Katholieke Universiteit Leuven in the framework of the Belgian Programme on Inter-university Poles of Attraction, initiated by the Belgian State, Prime Minister's Office for Science, Technology and Culture (IUAP-17), and in the framework of a Concerted Action Project MIPS (Model-based Information Processing Systems) of the Flemish Community, It is sponsored by Electrabel. 相似文献