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排序方式: 共有2117条查询结果,搜索用时 15 毫秒
81.
Bernhard Deufel Carsten Mueller Gavan Duffy Tom Kevenaar 《Datenschutz und Datensicherheit - DuD》2013,37(6):363-366
While developing the specifications for electronically enabled Machine Readable Travel Documents, the ICAO paid significant attention to security aspects related to the digital information stored in this type of electronic document. This has resulted in Passive and Active Authentication, Basic Access Control and Extended Access Control. The goal of Basic Access Control (BAC) is preventing unauthorized access to the chip data stored on eMRTDs. The PACE protocol has been developed as a future-proof method to overcome the limitations of BAC and to replace BAC in the future. In this paper the BioPACE protocol is proposed as a supplement to the PACE protocol. Besides verifying if the document holder is indeed the rightful owner, the BioPACE protocol provides a higher convenience for the bearer of the document. 相似文献
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Ass.-Prof. Dipl.-Ing. Dr. mont. Heinrich Mali Bernhard Spuida 《BHM Berg- und Hüttenm?nnische Monatshefte》2013,158(2):47-52
The mineralogical composition and structural properties of iron ores control their behaviour in industrial reduction plants. Micro-images of polished sections are processed by the software VisuMet to determine the proportions of limonite, hematite and magnetite. From the mineralogical composition and the structural properties of iron ores VisuMet assesses their reduction properties at standard reduction conditions. 相似文献
87.
Martin Pircher Bernhard Lechner Oliver Mariani Andreas Kammersberger 《Engineering Structures》2011,33(12):3755-3761
An investigation of the damage caused by road traffic on three reinforced concrete bridges was performed. This study was performed with a focus on the determination of the damage induced by heavy vehicles in relation to the damage caused by average everyday traffic. A damage model based on fatigue of reinforcement bars was employed. The stress cycles in the reinforcement bars were determined using measurements of the crack widths under traffic loading. Stress cycles were analyzed using the Rainflow Method and Miner’s Rule was employed to gain a measurement for the damage. Monitoring systems were installed on each of the three bridges and operated for several weeks continuously to collect input data for the damage model. Computer software was developed to process the monitoring data in the sense of the damage model. The described methodology was developed and used for the first time in the described project.Heavy traffic was shown to cause a disproportionate high portion of the overall damage on all three bridges. The obtained results indicated that the damage caused by singular events, such as the passage of a heavy vehicle, in relation to the damaging effects of every-day traffic differed significantly between the considered bridges. For one of the bridges the greatest damage from singular traffic events was computed for passages of special transport vehicles. The same bridge was also found to display the highest damage by a single passage in relation to average everyday traffic. Passages of short and heavy trucks with four and five axles were identified as the most detrimental traffic events on the other two bridges. 相似文献
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Dipl.-Ing. Dr. mont. Pawel Krajewski Christian Bernhard Roman Krobath Thomas Schaden Sergiu Ilie 《BHM Berg- und Hüttenm?nnische Monatshefte》2014,159(7):304-305
Continuous casting of steel free of surface cracks is still one of the major quality challenges in the whole steel production. The key roles for the phenomenon of surface cracking are played by the critical strain and the temperature-dependent material’s phenomena. The new In-Situ Characterization Bending (IMC-B) method will enable the investigation of the critical strains with respect to the cracking under the main continuous casting boundaries. This publication presents potential and interesting results of the IMC-B experiment. 相似文献
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Jürgen Mäurer Herman Requardt Bernhard Sander Friedrich D. Knollmann Arne-jörn Lemke Thomas J. Vogl Roland Felix 《Magma (New York, N.Y.)》1996,4(1):27-33
To investigate the application of a mini-coil surface system for high-resolution MRI, 60 volunteers were examined in a 1.5-T whole-body scanner. Two replaceable probe heads were available: a circular 2.5-cm coil and a quadratic 5-cm coil, both of which were placed directly on the skin. The skin layers, Achilles tendon and finger joints were examined with the 2.5-cm coil and a FOV of 25 × 25 mm2. A matrix of 256 × 256 pixels resulted in a pixel size of 0.098 × 0.098 mm2. For imaging of the carpal tunnel, the 5-cm coil was used in transverse orientation. The FOV was 50 × 50 mm2 so that a matrix of 256 × 256 pixels led to a pixel size of 0.195 × 0.195 mm2. The resulting spatial resolution permitted visualization of the epidermis, dermis and subcutis, resulting in clear definition of anatomical detail of the musculoskeletal system. MRI measurement of skin-layer thickness did not correlate with histometric data (p<0.05). This discrepancy was due in part to shrinkage of the tumor specimen on histologic preparation. Other causes include the motion artifacts and the limited accuracy of determining thickness on the MRI display unit. 相似文献