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1.
A mixed mode digital/analog special purpose VLSI hardware implementation of an associative memory with neural architecture is presented. The memory concept is based on a matrix architecture with binary storage elements holding the connection weights. To enhance the processing speed analog circuit techniques are applied to implement the algorithm for the association. To keep the memory density as high as possible two design strategies are considered. First, the number of transistors per storage element is kept to a minimum. In this paper a circuit technique that uses a single 6-transistor cell for weight storage and analog signal processing is proposed. Second, the device precision has been chosen to a moderate level to save area as much as possible. Since device mismatch limits the performance of analog circuits, the impact of device precision on the circuit performance is explicitly discussed. It is shown that the device precision limits the number of rows activated in parallel. Since the input vector as well as the output vector are considered to be sparsely coded it is concluded, that even for large matrices the proposed circuit technique is appropriate and ultra large scale integration with a large number of connection weights is feasible.  相似文献   
2.
Properties of optical coatings (e.g. low‐e or solar control) can be described and controlled using transmittance, reflectance and sheet resistance measurements. Multiple in situ transmittance measurement points allow a quick response to adjust different coating processes (layer thickness and homogeneity). For the final characterization of the coated substrate ex situ transmittance, reflectance and sheet resistance measurements are used. Accurate and reproducible measurements in a combination with Reverse Engineering methods admit monitoring all layers and in this way detecting slight drifts.  相似文献   
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4.
Extracellular vesicles secreted from adipose‐derived mesenchymal stem cells (ADSCs) have therapeutic effects in inflammatory diseases. However, production of extracellular vesicles (EVs) from ADSCs is costly, inefficient, and time consuming. The anti‐inflammatory properties of adipose tissue‐derived EVs and other biogenic nanoparticles have not been explored. In this study, biogenic nanoparticles are obtained directly from lipoaspirate, an easily accessible and abundant source of biological material. Compared to ADSC‐EVs, lipoaspirate nanoparticles (Lipo‐NPs) take less time to process (hours compared to months) and cost less to produce (clinical‐grade cell culture facilities are not required). The physicochemical characteristics and anti‐inflammatory properties of Lipo‐NPs are evaluated and compared to those of patient‐matched ADSC‐EVs. Moreover, guanabenz loading in Lipo‐NPs is evaluated for enhanced anti‐inflammatory effects. Apolipoprotein E and glycerolipids are enriched in Lipo‐NPs compared to ADSC‐EVs. Additionally, the uptake of Lipo‐NPs in hepatocytes and macrophages is higher. Lipo‐NPs and ADSC‐EVs have comparable protective and anti‐inflammatory effects. Specifically, Lipo‐NPs reduce toll‐like receptor 4‐induced secretion of inflammatory cytokines in macrophages. Guanabenz‐loaded Lipo‐NPs further suppress inflammatory pathways, suggesting that this combination therapy can have promising applications for inflammatory diseases.  相似文献   
5.
Distributed control systems are currently evolving towards industrial Internet of Things (IoT) systems communicating fully using Internet protocols. This creates opportunities for streamlining costly commissioning processes, which today require substantial manual work for installing, configuring, and integrating thousands of actuators and sensors. The vision of “plug-and-produce” control systems has been pursued for more than 15 years, but existing approaches fell short regarding configuration tasks and vendor neutrality. This paper introduces the standards-based IoT reference architecture OpenPnP, which allows largely automating the configuration and integration tasks of industrial commissioning processes. The architecture includes a number of design and technology decisions and the required implementation can be scaled down to resource-constrained industrial devices. This paper demonstrates how OpenPnP can reduce configuration and integration efforts up to 90% in typical settings, while potentially scaling well up to tens of thousands of communicated signals. Practitioners can orient their implementations towards OpenPnP, therefore potentially enabling “plug-and-produce” in many thousands of control systems.  相似文献   
6.
A simple method is presented by which the mean heat transfer coefficient at arbitrary geometries in a steady flow field can be determined. It is based on the measurement of the time dependent temperature and an evaluation that takes into account the conservation of thermal energy. For spheres of various sizes the method is exemplified demonstrating that the results agree well with those from the heat transfer literature.  相似文献   
7.
The tundish as a part of a continuous casting machine combines the discontinuous ladle metallurgy with the continuous solidification of slabs in the mould. The tundish plays a major role in the challenging task of “clean steel” production. That means the smallest number of inclusions and high cleanliness in all steel grades after changing the conditions at the inlet of the tundish. Inclusions hinder the metal forming process and lead often to fatigue. The cleanliness of steels is important to fulfil the customer's requirements. In the present study inclusion removal was simulated in a 1:3 scaled water model of a single‐strand tundish for the production of stainless steels with a particle counter. The particle counter is capable of counting a large number of particles with a wide range of diameters. The separation rate for particle diameters from dP = 1 ‐ 250 μm was determined with a counter for the water model tundish. With similarity conditions for the particles this deposition rate can be transformed to the melt flow in a steel tundish. The separation rate was measured for different flow rates in the water model tundish. A larger flow rate decreased the separation rate. Additionally, the separation rate for the tundish fitted with an impact pad was measured and showed a significant increase of separation for particles with a smaller diameter. Furthermore, the particle distribution in the tundish for different size groups of particles was investigated with and without an impact pad. Numerical simulations were carried out with the finite‐volume commercial code FLUENT using the realizable k‐ε turbulence model. A special boundary condition for the separation of particles at the surface was implemented.  相似文献   
8.
Horst Rückert 《Bautechnik》2006,83(6):422-427
A contribution to guaranteeing quality in earthwork. The compaction degree DPr are normally used for the quality control in earthworks. This paper presents for a weak cohesive soil that besides the water content not the compaction degree but rather the compaction energy W has the decisive influence on the characteristics of the shear strength, of the compressibility and of the water permeability. The determination of the in‐situ compaction energy during soil compaction is shown. Formulas and diagrams give the possibility to estimate the in‐situ soil characteristics. This requires the estimated values of the compaction energy W.  相似文献   
9.
The polymers of the aromatic nitrogen compounds N-methyl-pyrrole (P-N-Me-PPY), carbazole (PCarb), and aniline (PANI) have been investigated with electro-optical and surface analytical methods. The in-situ reflection spectra indicate the formation of polarons or bipolarons during electrochemical oxidation, depending on polymer type. The absorption bands can be attributed to changes in the electronic structure with regard to the applied potential. Photocurrent spectra of P-N-Me-PPY and PCarb show a p-type semiconducting behaviour for the polymers in the reduced state. The transition to the oxidized state with quasi-metallic properties is indicated by a significant shift in the Fermi level energy and can be followed with XPS and UPS measurements.  相似文献   
10.
HB Franz  N Benda  M Gonser  IT B?ckert  EC Jehle 《Canadian Metallurgical Quarterly》1998,123(3):218-22; discussion 222-3
Obstetric damage of the anorectal continence organ can lead to impaired anal continence. To assess the effect of birth, either with or without direct injury of the anal sphincter, 123 primiparae were studied. 41 patients with a midline episiotomy and 82 patients with an additional injury of the anal sphincter were assessed at a median of 21 weeks postpartum and compared with 18 healthy volunteers. Anorectal manometry as well as a standardized questionnaire were employed. Patients with an additional injury of the anal sphincter reported persistent flatus incontinence significantly more often (p = 0.0069) than patients with a midline episiotomy only. Incontinence of solid or liquid stool occurred only transiently. Compared to nulliparae in all primiparae a significant shortening of anal canal and a decreased squeeze pressure were observed. In addition, a significantly reduced resting pressure was seen in patients with an anal sphincter injury. The rectoanal inhibitory reflex was absent significantly more often following anal sphincter tear (p = 0.0023). Vaginal delivery, both with and without anal sphincter injury, leads to early detectable changes in anorectal sphincter function.  相似文献   
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