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111.
112.
Server‐side component models such as Enterprise JavaBeans (EJB) add powerful abstractions to the bare ‘business objects’ layer in order to support a clean separation of server‐side application logic from other concerns such as distribution, security, transaction management and persistence. An improved separation of concerns is also the main goal of aspect‐oriented programming (AOP). This paper compares the two approaches and reasons about the possibility of substituting (parts of) component models using AOP mechanisms. We conclude that AOP is a promising approach to eliminate important shortcomings of the container‐based component approach. However, our analysis of concrete aspect‐oriented languages shows that current AOP technology is not yet mature enough to supersede component models. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
113.
Consideration of the errors inherent in mapping historical glacier positions in Austria from the ground and space (1893-2001) 总被引:4,自引:0,他引:4
Dorothy K. Hall Klaus J. BayrWolfgang Schöner Robert A. BindschadlerJanet Y.L. Chien 《Remote sensing of environment》2003,86(4):566-577
The historical record of in situ measurements of the terminus positions of the Pasterze and Kleines Fleißkees glaciers in the eastern Alps of Austria is used to assess uncertainties in the measurement of decadal scale changes using satellite data. Topographic maps beginning in 1893, and satellite data from 1976 to 2001, were studied in concert with ground measurements to measure glacier changes. Ground measurements show that the tongue of the Pasterze Glacier receded ∼1150 m from 1893 to 2001, while satellite-derived measurements, using August 2001 Landsat Enhanced Thematic Mapper Plus (ETM+) data registered to an 1893 topographic map, show a recession of 1300-1800 m, with an unknown error. The measurement accuracy depends on the registration technique and the pixel resolution of the sensor when two satellite images are used. When using topographic maps, an additional source of error is the accuracy of the glacier position shown on the map. Between 1976 and 2001, Landsat-derived measurements show a recession of the terminus of the Pasterze Glacier of 479±136 m (at an average rate of 19.1 m a−1) while measurements from the ground showed a recession of 428 m (at an average rate of 17.1 m a−1). Four-meter resolution Ikonos satellite images from 2000 and 2001 reveal a shrinkage of 22,096±46 m2 in the Pasterze tongue. The nearby Kleines Fleißkees glacier lost 30% of its area between 1984 and 2001, and the area of exposed ice increased by 0.44±0.0023 km2, according to Landsat satellite measurements. As more recent satellite images are utilized, especially data that are geocoded, the uncertainty associated with measuring glacier changes has decreased. It is not possible to assess the uncertainty when an old topographic map and a satellite image are coregistered. 相似文献
114.
Anisotropic Filtering of Non-Linear Surface Features 总被引:17,自引:0,他引:17
A new method for noise removal of arbitrary surfaces meshes is presented which focuses on the preservation and sharpening of non‐linear geometric features such as curved surface regions and feature lines. Our method uses a prescribed mean curvature flow (PMC) for simplicial surfaces which is based on three new contributions: 1. the definition and efficient calculation of a discrete shape operator and principal curvature properties on simplicial surfaces that is fully consistent with the well‐known discrete mean curvature formula, 2. an anisotropic discrete mean curvature vector that combines the advantages of the mean curvature normal with the special anisotropic behaviour along feature lines of a surface, and 3. an anisotropic prescribed mean curvature flow which converges to surfaces with an estimated mean curvature distribution and with preserved non‐linear features. Additionally, the PMC flow prevents boundary shrinkage at constrained and free boundary segments. 相似文献
115.
Sabine Anderweit Christoph Licht Angela Kribs Christiane Woopen Klaus Bergdolt Prof. Dr. Bernhard Roth 《Ethik in der Medizin》2004,16(1):37-47
Definition of the problem: Physicians and nurses who work in neonatology—as in intensive care at all—are often forced to decide whether to stop or to continue with the treatment of a severely ill patient. The literature provides several decision making instruments, which are meant to help and to rationalize such decisions. Method and conclusion: Two of these instruments (“Schema zur ethischen Urteilsbildung nach dem Muster der aristotelischen Ethik”, Honnefelder 1994; “Nimwegener Methode für ethische Fallbesprechung”, Gordijn 1998) were tested by retrospectively examining two cases of our NICU. Results of our study show that the use of a decision making instrument is basically helpful. But the above mentioned instruments showed also shortcomings when used in the framework of neonatology. Therefore we developed the “Kölner Arbeitsbogen zur ethischen Entscheidungsfindung in der Neonatologie”, which is adapted to the specific needs of neonatology. 相似文献
116.
Commercially produced 0.03 % C, 0.08 % Nb, 0.01 % Ti high strength low alloyed (HSLA) steel in the form of 20 mm thick plates was investigated. The steel was thermomechanically processed and the mechanical properties of the steel were evaluated by tensile testing. Using analytical and high resolution transmission electron microscopy the distribution, morphology, composition, crystal structure and particle size of niobium and titanium carbonitrides were observed and identified in these steels. The distribution of the precipitates was found to be nearly random, with occasional occurrence of precipitation free zones. Complex agglomerates with a cubic TiN seed crystal overgrown by a cubic NbC particle were the most commonly observed precipitates. Further TEM analysis in the accelerated cooled and tempered specimens in 1/4 plate thickness did not reveal any evidence that additional precipitation in the ferrite occurred. Precipitation in ferrite was only detected after subsequent cold deformation and tempering of the same samples. By a combination of EFTEM, STEM, HRTEM in addition to EDX spectroscopy, a large population of strain induced NbC precipitates with fcc crystal structure ranging in size down to 2 nm were identified in the ferrite matrix. 相似文献
117.
The Treaty of the European Coal and Steel Community (ECSC), which expired in 2002, states in its Article 55 to promote technical and economic research with respect to the production and growing application of coal and steel. The results of funded research projects shall be made available to all representatives and partners concerned. For the European steel industry Article 55 was the basis for building up a steel research programme covering topics from raw materials to steel application and instigated a European network of researchers from the steel industry, research institutes and universities. On the basis of these research and development activities carried out by the ECSC steel research, the iron and steel industry has shown important advances in technology and environmental compatibility. Furthermore, the ECSC steel research has contributed to nearly all important technological developments. The main objective of the ECSC steel Research and Technology Development (RTD) programme was to sustain and develop the Community steel industry's competitiveness. The following report describes fundamental developments and activities within the framework of ECSC research with particular respect to hot metal production in the last 15 years. 相似文献
118.
M. Saeed Abaee Soodabeh Forghani Mohammad M. Mojtahedi Klaus Harms 《Journal of Sulfur Chemistry》2016,37(6):683-691
A facile procedure is developed for one-pot synthesis of a new group of dicyanoanilines. Tetrahydro-4H-thiopyran-4-one, 1, undergoes a pseudo four-component reaction with various aldehydes bearing different groups and two equivalents of malononitrile in aqueous media in the presence of triethylamine (Et3N). As a result, novel thiopyran-fused dicyanoanilines 4 are formed efficiently in the reaction mixtures in 90–97% yield within 9–12?h mixing at 40°C. Due to the polarity of the medium, products precipitate in the mixture spontaneously allowing for easy purification by recrystallization avoiding cumbersome chromatographic separations. Characterization of the products was performed by spectroscopic methods and, in one case, was further supported by X-ray crystallographic experiments. 相似文献
119.
120.
Andreas Menrad Thomas Goedecke Klaus‐Peter Gruender Manfred H. Wagner 《Packaging Technology and Science》2013,26(6):311-326
The effect of the wall thickness variation of blow‐moulded bodies made of high‐density polyethylene on an internal pressure test after prestoring the packaging with standard liquids was evaluated in experiments and simulations. The objects of the investigation were jerrycans used for the transportation and storage of dangerous goods. The wall thickness was determined using two alternative methods to the magnetostatic measurement. These alternative methods are used for research purpose to get a volumetric model of the jerrycan wall as a geometric model for the simulation. The comparison of the experiments and the simulations of the internal pressure test were performed using the digital image correlation method. The integral strain and deformation of the whole jerrycan was detected by measuring the total mass of the jerrycan being filled with water during the internal pressure test. This is a suitable alternative to the optical measurements of local deformation by the digital image correlation method. Prestorage at 40 °C without the influence of chemicals strengthens the jerrycan, whereas the swelling effect of butyl acetate and hydrocarbon mixture softens the jerrycan. The comparison with the experiment is necessary to verify the accuracy of the simulation. It shows that the deformation can be simulated more precisely by using the actual measured geometry. The weakening of the high‐density polyethylene caused by a hydrocarbon mixture can be simulated using the Arrhenius equation. The aim of the simulation was to discover whether it is possible to use specimens to predict the behaviour of a packaging both after the influence of standard liquids. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献