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991.
This paper proposes a hardware-in-the-loop simulation (HILS) approach for the design and verification of a production system. The design of a production system involves two major activities: mechanical design (device specification and layouts) and electrical design (device behaviour and system control). Conventionally, the mechanical and electrical design activities have been performed sequentially, wasting time. We propose a concurrent procedure of mechanical and electrical design based on the HILS methodology to cope with this problem. The proposed HILS approach provides two major benefits: (1) the verified control program can be directly used for the real plant with minor adaptations; and (2) the verified 3D layout model can be used to generate the detailed drawings for the implementation of the plant. We can minimise the stabilisation time of a production system, since most mechanical and electrical errors can be found and fixed using HILS.  相似文献   
992.
Magnetoelectric (ME) property modulation in heterostructured (Ni0.5Zn0.5)Fe2O4/Pt/Pb(Zr0.3Ti0.7)O3 (NZFO/Pt/PZT) thin films on platinized Si substrate by thermal annealing condition variation was studied. In an attempt to prevent interfacial reaction between NZFO and PZT layers during high temperature annealing, thin Pt layer was deposited which can serve as inter-diffusion barrier as well as electrode. The ferroelectric, magnetic, and ME properties of the heterostructured film were noticeably modulated due to microstructural evolution and clamping relaxation developed during thermal annealing process. Room temperature ME voltage coefficient of the heterostructured thin films was enhanced with increasing annealing temperature and reached to 29 mV/cm·Oe when annealed at 650 °C.  相似文献   
993.
Flexible piezoelectric acoustic sensors have been developed to generate multiple sound signals with high sensitivity, shifting the paradigm of future voice technologies. Speech recognition based on advanced acoustic sensors and optimized machine learning software will play an innovative interface for artificial intelligence (AI) services. Collaboration and novel approaches between both smart sensors and speech algorithms should be attempted to realize a hyperconnected society, which can offer personalized services such as biometric authentication, AI secretaries, and home appliances. Here, representative developments in speech recognition are reviewed in terms of flexible piezoelectric materials, self-powered sensors, machine learning algorithms, and speaker recognition.  相似文献   
994.
In order to effectively remove alumina inclusions suspending in ultra-low C steel during RH process, the dissolution kinetics of alumina in molten CaO–Al2O3–FetO–MgO–SiO2 oxide was investigated. A crucible dissolution technique was used where the alumina crucible was allowed to dissolve in the slag of various conditions ((% CaO)/(% Al2O3), (% FetO), temperature). The obtained data were interpreted using a kinetic mass transport equation to obtain the mass transport coefficient (km) in each condition. Increasing (% CaO)/(% Al2O3), (% FetO), and temperature increased the dissolution rate as well as the km provided that the slag composition is not close to its saturation composition by alumina. In order to simulate the dissolution of alumina inclusion in the RH slag, which cannot be measured by a confocal scanning laser microscopy (CSLM) at present due to the opaqueness of the slag, the modified invariant interface approximation was employed. Along with the obtained km, the viscosity of slag, and a reference experiment using the CSLM, the dissolution kinetics of alumina inclusion in the FetO-containing RH slag was predicted. The time required for the dissolution of alumina inclusions from liquid steel to RH slag was discussed.  相似文献   
995.
This review presents the results of a conference on ikat textiles organized in the context of the exhibition Striking Patterns: Global Traces in Local Ikat Fashion at the Museum der Kulturen Basel, Switzerland (October 2016 to March 2017). Academics and professional experts, some of them working for NGOs, debated often neglected potentialities as well as the future of contemporary ikat design and other intricately patterned handwoven textiles: the significance of new patterns; intellectual property rights; and educational encouragement. The general focus lay on the controversially perceived innovation of textile patterns in Indonesia and Timor-Leste. We will here present the main arguments of the discussion and our own suggestions for further research.  相似文献   
996.
997.
Indian Punjab, a strategically important region from India’s national food security standpoint, is increasingly the focus of attention for academics and policymakers because of serious concerns about over-exploitation of its groundwater resources. Currently, policy makers and agricultural researchers/scientists in India are in a fix to prescribe an alternative, probably more sustainable, crop-mix to farmers that can save water while maintaining farm incomes. Using primary data from 120 farmers, this paper evaluates the current situation of groundwater resources in Punjab, and outlines the major socio-economic factors that have a significant association with the change in the groundwater depth in this region. General ANOVA regression results suggest that groundwater depth varied significantly with respect to agro-climatic regions, crop diversity, and farmer education. Crop diversity had an inverse relationship with groundwater depth whereas the association between farmer education and groundwater depth was non-linear although in the case of Gurdaspur, they showed a direct relationship. In the central zone of Indian Punjab, groundwater level on 92% of the farms had depleted by more than 0.60 m annually between 2000 and 2010, while the current state of groundwater resources in the other two regions was not so serious and are manageable for the time being. However, if the existing policy framework for groundwater resources in the state, which allows the state government to release 0.11 million more connections to farmers, putting much pressure not only on the groundwater resources but also burdening the state exchequer, continues, Punjab may end up losing all its groundwater resources for ever. Considering this alarming situation, one-fifth of the farmers surveyd agreed to delay the sowing of rice by another 2 weeks i.e. up to 30 June which could save the fast depleting groundwater resources in Punjab.  相似文献   
998.
We investigated the appearance of flow and weld lines when metallic pigments are used in polymer blends and how such lines can be eliminated by improving the pigment particle shape and optimizing pigment loading. Acrylonitrile butadiene styrene copolymer and two types of aluminum flakes, lamellar and three-dimensional (3D), were blended in a twin-screw extruder with a screw diameter of 25 mm. The temperatures from the hopper to the nozzle were 140, 180, 220, 220, 220, 220, and 220°C. Weld and flow lines were observed using field-emission scanning electron microscopy and energy dispersive X-ray spectroscopy of specially manufactured injection specimens. In the flow line region, traditional lamellar flakes were randomly oriented, while 3D flakes exhibited a distinct and stable orientation. Based on these observations, flow and weld lines in a finished metal/polymer blend can be minimized by using 3D metal particles in place of lamellar flakes. We also investigated the effects of aluminum flake loading on weld and flow line visibility. At low loading, weld lines were clearly visible due to the lack of pigmentation in the front of the polymer flow. Conversely, high loading resulted in relatively high concentrations of pigment near the weld line area, reducing weld line visibility. These findings suggest that there is an optimum metal loading level where the visibility of flow and weld lines is minimized.  相似文献   
999.
A quality-by-design approach was adopted to develop telmisartan potassium (TP) tablets, which were bioequivalent with the commercially available Micardis® (telmisartan free base) tablets. The dissolution pattern and impurity profile of TP tablets differed from those of Micardis® tablets because telmisartan free base is poorly soluble in water. After identifying the quality target product profile and critical quality attributes (CQAs), drug dissolution, and impurities were predicted to be risky CQAs. To determine the exact range and cause of risks, we used the risk assessment (RA) tools, preliminary hazard analysis and failure mode and effect analysis to determine the parameters affecting drug dissolution, impurities, and formulation. The range of the design space was optimized using the face-centered central composite design among the design of experiment (DOE) methods. The binder, disintegrant, and kneading time in the wet granulation were identified as X values affecting Y values (disintegration, hardness, friability, dissolution, and impurities). After determining the design space with the desired Y values, the TP tablets were formulated and their dissolution pattern was compared with that of the reference tablet. The selected TP tablet formulated using design space showed a similar dissolution to that of Micardis® tablets at pH 7.5. The QbD approach TP tablet was bioequivalent to Micardis® tablets in beagle dogs.  相似文献   
1000.
Journal of Materials Science: Materials in Electronics - The effects of doping a trace of Fe2O3 on the structural and electrical properties of 8 mol% yttria-stabilized zirconia (8YSZ) are...  相似文献   
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