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41.
Production of extrudates from cereals is an often-used technological process in today’s world food industry. Extrudates from corn flour produced using the twin-screw extrusion process and enriched with whey protein concentrate represent high-quality source of proteins and fats. Whey protein concentrate (WPC) as a valuable source of proteins and minerals is one of the highest-quality components for possible extrudate enrichment. In this paper, the influence of various WPC addition and some extrusion process parameters such as feed moisture content ( QtextHtext2 textO Q_{{{text{H}}_{text{2}} {text{O}}}} ) on physicochemical properties of directly expanded corn flour extrudates manufactured in twin-screw co-rotating extruder was investigated. Whey protein concentrate was added in the following ratios 7.5%, 15% and 22.5% and water in 10.08, 12.18 and 14.28 L/h. Final composition of products is determined with measuring of protein, fat and water shares, water absorption index (WAI) and water solubility index (WSI). With added WPC and with increase of water volume flow, there was a significant rise in total protein, fat and water content in final products, as well as lowering of WSI and rising of WAI indexes. The statistical analysis of the obtained data shows that the lowest WSI and the highest WAI had samples with the largest share of WPC (22.5%) and water volume flow of 14.28 L/h. Colour is measured for each sample, and results were represented with hue angle (H), chroma (C) and lightness (L) values. Process parameters, WPC and QtextHtext2 textO Q_{{{text{H}}_{text{2}} {text{O}}}} influence the increase of saturation of C and lightness of L colour value, while H value stays unchanged. Mean value of H was 90.14 ± 1.06, which corresponds to dominance of yellow colour of samples.  相似文献   
42.
Robotic technologies, whether they are remotely operated vehicles, autonomous agents, assistive devices, or novel control interfaces, offer many promising capabilities for deployment in real‐world environments. Postdisaster scenarios are a particularly relevant target for applying such technologies, due to the challenging conditions faced by rescue workers and the possibility to increase their efficacy while decreasing the risks they face. However, field‐deployable technologies for rescue work have requirements for robustness, speed, versatility, and ease of use that may not be matched by the state of the art in robotics research. This paper aims to survey the current state of the art in ground and aerial robots, marine and amphibious systems, and human–robot control interfaces and assess the readiness of these technologies with respect to the needs of first responders and disaster recovery efforts. We have gathered expert opinions from emergency response stakeholders and researchers who conduct field deployments with them to understand these needs, and we present this assessment as a way to guide future research toward technologies that will make an impact in real‐world disaster response and recovery.  相似文献   
43.

In this study, zinc–silica–borate glass structures doped with rare earth (RE) oxides Eu2O3 and Nd2O3 were synthesized with classical melting–quenching technique. 60ZnO–10SiO2–(30 – x)B2O3:xRE (x?=?0, 0.5, 1, 1.5 mol%) composition was chosen as the structure. The doping effect of two different rare earth oxides (individually) at different ratios was investigated according to the structural, physical, and optical properties of the glass structure. Structural properties of the synthesized glasses were determined with Fourier transform infrared (FTIR) device, and densities (ρ) and molar volumes (Vm) of the glasses were measured with Archimedes method, and optical properties were determined with UV–Visible (UV–Vis-NIR) device. FTIR results show that BO3 units increased in all RE-doped glasses. While densities of the synthesized glasses varied between 3.755 and 3.941 g cm??3, indirect bandgaps varied between 3.219 and 3.645 eV. The glass with the highest transmittance was the 1% Eu2O3-doped glass with a transmittance of 84%. While band edges shifted slightly toward short wavelengths in glasses doped with Nd2O3, they shifted to longer wavelengths in glasses doped with Eu2O3.

  相似文献   
44.
Terahertz (THz) radiation probes intermolecular interactions through crystal lattice vibrations, allowing the characterization of solid materials. Thus, THz spectroscopy is a promising alternative to mainstream solid-state analytical tools such as X-ray diffraction or thermal analysis. The method provides the benefits of online measurement, remote sampling and three-dimensional imaging, all of which are attractive for quality control and security applications. In the context of pharmaceutical solids, THz spectroscopy can differentiate and quantify different forms of active pharmaceutical ingredients. Here, we apply this technique to monitor a dynamic process involving two molecular crystals. In particular, we follow the mechanochemical construction of a two-component cocrystal by grinding together phenazine (phen) and mesaconic acid (mes). To rationalize the observed changes in the spectra, we conduct lattice dynamics calculations that lead to the tentative assignment of at least one feature in the cocrystal THz spectrum.  相似文献   
45.
The goal of the Spincopter project was to design an energy efficient aircraft capable of autorotation glide that could be used for both indoor and outdoor surveillance. This paper demonstrates how to utilize the self-rotating capability of the Spincopter in order to acquire a 3D image of its environment and localize predefined object(s). The omnidirectional capabilities of such an UAV extends the otherwise very limited field of view of conventional cameras usually used for aerial photography and surveillance. The paper presents the theoretical background and the actual implementation of such a system. It presents the resulting images and offers a brief survey of the image quality.  相似文献   
46.
47.
In this study, the stair pressurization system in a 40-storey high office building in Istanbul is investigated through field tests, in order to understand the effect of the presence of a non-pressurized vestibule (fire protection lobby, FPL) before entering the stair at each floor. The building without FPL is simulated by keeping only one of the two doors (of the stair and FPL) open at each floor. This method gave an opportunity to fix other parameters affecting the stair pressurization system and check solely the effect of FPL. Two different cases are taken into account, where the first one (all doors closed) analyses the condition that all stair doors are kept closed and the second one (critical doors are open) is conducted when the stairwell is opened to the floor on a given level (fire floor) and the stair termination door at the discharge floor is kept open. For both cases, the availability of the FPL is investigated by using the aforementioned arrangement. Under the conditions with approximately the same pressurized air flow rate at all doors closed condition, it is found that the availability of FPL increases the pressure difference between the stairwell and the corridor by a factor of approximately 2.2. This is also justified by using empirical formulations available in literature, where this ratio is calculated as 2.0. The results of this study showed that the FPL arrangement improves the effectiveness of pressurization system in a very high-rise building, despite some tolerable drawbacks.  相似文献   
48.
The aim of this study is to experimentally and theoretically investigate the flexural behavior of concrete beams reinforced with fiber reinforced polymer (FRP) bars. In this research, three types of experiments were made. First, the tensile properties of FRP and steel bars were tested, then the bond-slip behavior between bars and concrete was tested on standard specimens and, in the end, three series of concrete beams reinforced with GFRP, CFRP and steel bars were tested up to failure. The theoretical model for calculating deflections was developed, which included bond-slip behavior of FRP bars. The theoretical results were compared to the test results of beam deflections, as well to deflection results obtained by theoretical models developed by other authors.  相似文献   
49.
This study addresses a capacitated intermediate product selection and blending problem typical for two-stage production systems in the food processing industry. The problem involves the selection of a set of intermediates and end-product recipes characterising how those selected intermediates are blended into end products to minimise the total operational costs under production and storage capacity limitations. A comprehensive mixed-integer linear model is developed for the problem. The model is applied on a data set collected from a real-life case. The trade-offs between capacity limitations and operational costs are analysed, and the effects of different types of cost parameters and capacity limitations on the selection of intermediates and end-product recipes are investigated.  相似文献   
50.
One of the important design elements for a good production system is material handling. In cases where it is not well-designed, it can be the bottleneck in the system. Moreover, it can cause a lot of wastes such as waiting time, idle time, and excessive transportation and cost. In this study, material handling in lean-based production environments is taken into account. Depending on the lean structure of the production systems such as being pull-based, smooth, and repetitive, delivering the materials to the stations periodically becomes important. At this point, milk-run trains are highly used in real applications since they enable the handling of required amount of materials on a planned basis. With this study, it is aimed to develop a specific model for milk-run trains which travel periodically in the production environment on a predefined route in equal cycle times with the aim of minimizing work-in-process and transportation costs. Since the milk-run trains having equal cycle times start their tours at the same time intervals, it becomes simple to manage them. For this reason, they are used in lean production systems where level scheduling is performed. The developed model is based on mixed-integer linear programming, and since it is difficult to find the optimum solution due to the combinatorial structure of the problem, a novel heuristic approach is developed. A numerical example is provided so as to show the applicability of the mathematical model and the heuristic approach.  相似文献   
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