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991.
992.
Fingerprint recognition technology is an important part of criminal investigations it is the basis of some security systems and an important tool of government operations such as the Immigration and Naturalization Services, registration procedures in the Armed Forces, and so forth. After the tragic events of September 11, 2001, the importance of reliable fingerprint recognition technology became even more obvious. In the current study, pressure-induced changes of distances between ridges of a fingerprint were measured. Using calibrated silicon pressure sensors we scanned the distribution of pressure across a finger pixel by pixel, and also generated maps of an average pressure distribution during fingerprinting. Emulating the fingerprinting procedure employed with widely used optical scanners, we found that on average the distance between ridges decreases by about 20% when a finger is positioned on a scanner. Controlled loading of a finger demonstrated that it is impossible to reproduce the same distribution of pressure across a given finger during repeated fingerprinting procedures. 相似文献
993.
Automatic TEM image alignment by trifocal geometry 总被引:1,自引:0,他引:1
Here we propose a novel method for automatic, markerless, feature‐based alignment of TEM images suitable for electron tomography. The proposed method, termed trifocal alignment, is more accurate than the previous markerless methods. The key components developed are: (1) a reliable multi‐resolution algorithm for matching feature points between images; (2) a robust, maximum‐likelihood‐based estimator for determining the geometry of three views – the trifocal constraint – required for validating the correctness of the matches; and (3) a robust, large‐scale optimization framework to compute the alignment parameters from hundreds of thousands of feature point measurements from a few hundred images. The ability to utilize such a large number of measurements successfully compensates for point localization errors. The method was experimentally confirmed with electron tomography tilt series of biological and material sciences samples, consisting of from 40 to 150 images. The results show that, with this feature‐based alignment approach, a level of accuracy comparable with fiducial marker alignment can be achieved. 相似文献
994.
Total planar area can be estimated based on sampling by a lattice of figures (e.g. point patterns, line segments, quadrats). General formulae are provided for the approximation of mean squared errors. The approximation formulae are products of the boundary length and of a parameter that depends only on the sampling scheme. An R package is provided by the authors for the numerical computation of the mean squared error formulae. The speed of convergence of the mean squared error approximation is assessed on the basis of several simulations. Several sampling schemes are compared in view of the approximated mean squared errors. 相似文献
995.
In this study, porous solid materials were produced with mixture combinations of materials such as tragacanth, cement, and pumice aggregate. Thermal conductivities of the produced materials were determined using hot wire methodology. The thermal conductivities of the produced samples ranged from 0.433 to 0.177 W/mK, depending on pumice diameter, pumice, tragacanth, and cement rates. A new model was developed to determine the effective thermal conductivities of the produced samples. The thermal conductivities obtained by the measurements were compared to the ones predicted by the model. The predicted values deviated as 1–31% from the measured values. It was finally shown that the experimental results were in good agreement to the predicted results. 相似文献
996.
997.
Building sustainability assessment tools (BSATs) aim to promote and rank the sustainability of building stock. This paper makes a deep comparative analysis on how dwellings are evaluated by five BSAT and one performance-based design tool. The comparison is based on: (i) the purpose of assessment; (ii) sustainability dimensions considered; (iii) indicators addressed; (iv) life cycle phases considered by the indicators; (v) type of indicators; (vi) measurements; (vii) aggregation processes; and (vii) life cycle phases during which the assessment was carried out. The evaluation showed that the scope of BSAT varies significantly as well as the life cycle phases addressed in the assessment. Financial issues are often excluded from the assessment. None of the schemes is totally quantitative or qualitative in their measurement system; all have different types of indicators and different ways to assess them. This research provides researchers and stakeholders with important inside knowledge on the tools that allow the development and construction of more sustainable buildings. 相似文献
998.
Lingzhi Xia Manir U. Isham Vladimir Ponomarev 《Journal of Nuclear Science and Technology》2016,53(10):1513-1520
Performance of a recently developed signal processing system for CANDU (Canada Deuterium Uraniu) reactor shutdown system 1 (SDS1) is evaluated in this paper. The evaluation is carried out in MATLAB/Simulink software environment as well as with an existing power measurement and signal processing system. The new signal processing algorithm is obtained based on the synthesis of several first order low pass filters with different delayed time constants. Throughout this paper, a special attention has been paid to compare the new signal processing system with the existing one. The dynamic behavior of the new signal processing system in the practical large loss of coolant accidents (LLOCA) events has also been examined. Simulation results show that during the LLOCA event, the reactor trip time, as well as the peak power, is decreased remarkably. Through the simulation studies, it has convincingly demonstrated that the new signal processing system has significant advantages over the existing system in terms of the improved trip response and accommodation of the spurious trip immunity. This advantage will significantly enhance the safety margin, or will bring economical benefits to nuclear power plants. 相似文献
999.
1000.
Bernardo Mançano Fernandes 《Landscape Research》2019,44(7):892-907
ABSTRACTFrom the perspective of Brazilian agrarian geography, the conflicts generated by land tenure disputes have as protagonists the families of the Landless Workers’ Movement (Movimento dos Trabalhadores Rurais Sem Terra), traditional landowners, and agribusiness corporations. In this article, we present a reflection on land conflicts and the spatial and territorial production of latifundia, peasant smallholders, and large-scale agribusiness through studies of the landscapes of two municipalities in the state of São Paulo. Among the various tools for analysing territorial disputes, Google Earth can be used for local, regional, and international comparative studies of how landscapes have been transformed. Informed by traditional research, the article analyses a diversity of photographs, from satellite to field shots, as evidence of landscapes that express conflicting social relations in disputes over different models of social and territorial development. 相似文献