Modulation Classification of MFSK Modulated Signals Using Spectral Centroid

Wireless Personal Communications - This study utilizes higher order spectrum in order to achieve satisfactory probability of correct classification of M-ary Frequency Shift Keying (MFSK) modulated...     

Effects of microwave and conventional baking on the oxidative stability and fatty acid composition of puff pastry

The effects of microwave and conventional baking on the fatty acid and trans fatty acid compositions of puff pastries, which contain high amounts of hydrogenated fat, were investigated. In addition, free fatty acids, peroxide value, and induction time for oxidative stability by the Rancimat method have been compared for microwave- and conventionally baked puff pastries. The data indicate there were considerable changes in acidity, peroxide value, and Rancimat induction time in both microwave- and conventionally baked samples. Although the content of saturated fatty acid such as palmitic and stearic and the ratio of saturated to unsaturated fatty acids did not change significantly, an apparent increase was determined in trans oleic acid levels by both baking methods. In addition, a significant decrease in linoleic acid content of the samples was found by microwave baking.     

Parametric code for generation of finite‐element model of nonwovens accounting for orientation distribution of fibres

A novel finite‐element modelling code developed to investigate the structural behaviour of nonwoven materials is presented. The technique allows modelling of a nonwoven fabric as a continuous–discontinuous medium with a given pattern of bond points and a large number of constituent fibres with arbitrary orientation distribution. The parametric feature of the code provides automatic modelling of nonwoven materials according to design parameters in a very efficient way. The effect of fibre length is also included for the first time in a finite element model of a nonwoven. The developed code is very flexible and it is possible to be extended to further studies such as damage behaviour.Copyright © 2013 John Wiley & Sons, Ltd.     

Effects of modified atmosphere packaging (MAP) on the microbiological quality and shelf life of ostrich meat

Effects of various concentrations of O₂/CO₂ in modified atmosphere packaging on the microbiological quality and shelf-life of ostrich meat was investigated. Nine–12 months old ostriches were used. The iliofibularis muscle was cut into small cubes that were divided into five groups and then separately packaged under various gas mixes: air and O₂:CO₂:N₂ ratios of 80:20:0, 60:20:20, 60:40:0, and 40:40:20, using 2 different headspace ratios (1:1 and 3:1). The packaged meats were kept at 4 °C for 10 days and were analysed microbiologically, physico-chemically and sensorially. As a result, the meat quality and shelf-life of ostrich meat under various gas compositions were improved; microbial growth was delayed due to high CO₂ usage and shelf-life was increased by 5–7 days. However, an undesired loss of red colour of the ostrich meat may affect consumer acceptance.     

约束混凝土的应力-应变分析模型

众所周知,混凝土的强度和延性在很大程度上取决于侧向约束水平。约束的刚度和基本性能（弹性,弹塑性等）是影响混凝土性能的重要因素。本研究中,建立了一个新的简单的约束混凝土模型来描述三向受压状态下混凝土的轴向和侧向变形特性。定义约束混凝土的轴向应力-应变关系为非线性曲线的弹性区。采用常失效能量准则定义了应力-应变关系曲线的下降区域。     

Comparison of conventional and collapsed region operation of capacitive micromachined ultrasonic transducers

We report experimental results from a comparative study on collapsed region and conventional region operation of capacitive micromachined ultrasonic transducers (CMUTs) fabricated with a wafer bonding technique. Using ultrasonic pulse-echo and pitch-catch measurements, we characterized single elements of 1-D CMUT arrays operating in oil. The experimental results from this study agreed with the simulation results: a CMUT operating in the collapsed region produced a higher maximum output pressure than a CMUT operated in the conventional region at 90% of its collapse voltage (3 kPa/V vs. 16.1 kPa/V at 2.3 MHz). While the pulse-echo fractional bandwidth (126%) was higher in the collapsed region operation than in the conventional operation (117%), the pulse-echo amplitude in collapsed region operation was 11 dB higher than in conventional region operation. Furthermore, within the range of tested bias voltages, the output pressure monotonously increased with increased bias during collapsed region operation. It was also found that in the conventional mode, short AC pulses (larger than the collapse voltage) could be applied without collapsing the membranes. Finally, while no significant difference was observed in reflectivity of the CMUT face between the two regions of operation, hysteretic behavior of the devices was identified in the collapsed region operation.     

Messmodelle im Ingenieurbauwesen. Eine Bilanz

Measurement models in civil engineering. A review The research project “‘Last Witnesses’ Measurement Models in Civil Engineering – Scientific Significance and Preservation” was funded as part of the priority program 2255 “Construction as Cultural Heritage” of the German Research Foundation (DFG) and consists of three sub-projects divided between the University of Innsbruck, the Karlsruhe University of Applied Sciences and the Technical University of Munich. The project aimed to locate the last surviving measurement models in German-speaking countries, document them, classify them in terms of construction history, digitise them and evaluate their state of conservation. This report is intended to provide an overview of the initial situation, the approaches, the difficulties and the results and findings achieved in the project.