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Time dependent behavior of elements combining ultra-high performance fiber reinforced concretes (UHPFRC) and reinforced concrete 总被引:1,自引:1,他引:0
Structural elements combining Ultra-High Performance Fiber Reinforced Concretes (UHPFRC) and concrete offer a high potential
in view of rehabilitation and modification of existing structures. The investigation of the time-dependent behavior of composite
“UHPFRC-concrete” elements is a fundamental step in the determination of durability and serviceability. For this, an experimental
program was conducted on large composite “UHPFRC-concrete” beams and a numerical model was validated with the test results.
The experimental results and a parametric study performed with the numerical model showed that UHPFRC and normal strength
reinforced concrete are compatible in the long-term and that the critical period of composite “UHPFRC-concrete” elements are the first 90 days after the casting of the UHPFRC layer. Thus, the high potential
of such composite elements can be exploited also in the long term. 相似文献
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Eugen Michel 《Holz als Roh- und Werkstoff》1938,1(9):332-335
Zusammenfassung Die gro?e Bedeutung, die dem Holz für die Errichtung von Tragwerken wie auch für die Ausstattung von R?umen zukommt, rechtfertigt
es, sich einmal die akustischen Eigenschaften dieses Baustoffes zu vergegenw?rtigen.
Grunds?tzlich handelt es sich dabei um zweierlei Dinge, n?mlich raumakustisch um die Einwirkung auf die H?rsamkeit, d. h.
um die Beeinflussung von Schall, der in einem Raum erzeugt wird und in diesem selbst verl?uft, und dann bauakustisch um die
D?mmung, d. h. um die F?higkeit, einen auftreffenden Schall zurückzuhalten, ihn nicht nach au?en, also in andere R?ume oder
ins Freie dringen zu lassen. 相似文献
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We present an algorithm for combining the elements of subsequences of a sequence with an associative operator. The subsequences are given by a sliding window of varying size. Our algorithm is greedy and computes the result with the minimal number of operator applications. 相似文献
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Location-based applications such as Facebook Places, Foursquare, or Loopt typically use location services to manage mobile object positions. However, exposing precise user positions raises user privacy concerns, especially if location service providers are not fully trusted. To enable the secure management of private user positions in non-trusted systems, we present two novel position sharing approaches based on the concept of multi-secret sharing. We improve existing geometric position sharing approaches by Dürr et al. [2] and Skvortsov et al. [3] by considering continuous position updates and by increasing the robustness against various attacks. Furthermore, we present the first position sharing approach for symbolic location models. 相似文献
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Albrethsen J Kaas A Schönle E Swift P Kocova M Gammeltoft S Hansen L Mortensen HB 《Proteomics. Clinical applications》2009,3(3):383-393
Proteomics analysis of serum from patients with type 1 diabetes (T1D) may lead to novel biomarkers for prediction of disease and for patient monitoring. However, the serum proteome is highly sensitive to sample processing and before proteomics biomarker research serum cohorts should preferably be examined for potential bias between sample groups. SELDI‐TOF MS protein profiling was used for preliminary evaluation of a biological‐bank with 766 serum samples from 270 patients with T1D, collected at 18 different paediatric centers representing 15 countries in Europe and Japan over 2 years (2000–2002). Samples collected 1 (n = 270), 6 (n = 248), and 12 (n = 248) months after T1D diagnosis were grouped across centers and compared. The serum protein profiles varied with collection site and day of analysis; however, markers of sample processing were not systematically different between samples collected at different times after diagnosis. Three members of the apolipoprotein family increased with time in patient serum collected 1, 6, and 12 months after diagnosis (ANOVA, p<0.001). These results support the use of this serum cohort for further proteomic studies and illustrate the potential of high‐throughput MALDI/SELDI‐TOF MS protein profiling for evaluation of serum cohorts before proteomics biomarker research. 相似文献
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Yannick Schellander Marius Winter Maurice Schamber Fabian Munkes Patrick Schalberger Harald Kuebler Tilman Pfau Norbert Fruehauf 《Journal of the Society for Information Display》2023,31(5):363-372
In this work, real-time ultraviolet photodetectors are realized through metal–semiconductor–metal (MSM) structures. Amorphous indium gallium zinc oxide (a-IGZO) is used as semiconductor material and gold as metal electrodes. The readout of an individual sensor is implemented by a transimpedance amplifier (TIA) consisting of an all-enhancement a-IGZO thin-film transistor (TFT) operational amplifier and a switched capacitor (SC) as feedback resistance. The photosensor and the transimpedance amplifier are both manufactured on glass substrates. The measured photosensor possesses a high responsivity R , a low response time t R E S , and a good noise equivalent power value NEP . 相似文献