Digital to Analog Converter

A digital to analog converter (DAC) for converting a digital signal (DS) having a maximum voltage range which corresponds to a first supply voltage (UL) into an analog signal (UOUT) having a maximum voltage range which corresponds to a second supply voltage (UH). The first supply voltage (UL) is offered between a first supply terminal (VSS) and a second supply terminal (VDDL). The second supply voltage (UH) is offered between the first supply terminal (VSS) and a third supply terminal (VDDH).; The digital to analog converter (DAC) comprises conversion resistors (RCNV0 - RCNVn) and coupling means (CPL) for coupling a number of said conversion resistors (RCNV2 - RCNVn) in between the first supply terminal (VSS) and an output terminal (OUT), and for coupling the remainder of said conversion resistors (RCNV0 - RCNV1) in between the third supply terminal (VDDH) and the output terminal (OUT). The value of said number depends on the data content of the digital signal (DS). Digital to analog converters are generally implemented in ICs. For modern ICs there is a trend toward ever decreasing supply voltages. Often circuits implemented in new IC processes have to be able to interface with ICs processed in less modern processes which are generally operated on higher supply voltages.; In the modern process, therefore, circuits designed in modern ICs have to cope with voltages which are above the maximum specification for their transistors or other components. The DA-converter (DAC) mentioned above fulfils this requirement by the fact that material, such as polycrystalline silicon, is used for the conversion resistors (RCNV2 - RCNVn), which material can cope with relatively high voltages, and furthermore by the fact that only the coupling means (CPL) have to be designed to cope with relatively high voltage

How Bed Composition Affects Erosion by Debris Flows—An Experimental Assessment

Abstract A solid physical understanding of debris‐flow erosion is needed for both hazard prediction and understanding landscape evolution. However, the processes and forces involved in erosion by debris flows and especially how the erodible surface itself influences erosion are poorly understood. Here, we experimentally investigate the effects of bed composition on debris‐flow erosion, by systematically varying the composition of an erodible bed in a small‐scale debris‐flow flume. The experiments show that water and clay content of an unconsolidated bed significantly control erosion magnitude by affecting the transfer of pore pressure, loading conditions, and contraction‐dilation behavior of the bed. As the water content increases and the bed comes close to saturation, erosion increases rapidly, whereas for clay content an optimum for erosion exists around a clay content of 3%–4%. Our results show that small variations in bed composition can have large effects on debris‐flow erosion, and thus volume growth and hazard potential

Digital to Analog Converter

A digital to analog converter (DAC) for converting a digital signal (DS) having a maximum voltage range which corresponds to a first supply voltage (UL) into an analog signal (UOUT) having a maximum voltage range which corresponds to a second supply voltage (UH). The first supply voltage (UL) is offered between a first supply terminal (VSS) and a second supply terminal (VDDL). The second supply voltage (UH) is offered between the first supply terminal (VSS) and a third supply terminal (VDDH).; The digital to analog converter (DAC) comprises conversion resistors (RCNV0 - RCNVn) and coupling means (CPL) for coupling a number of said conversion resistors (RCNV2 - RCNVn) in between the first supply terminal (VSS) and an output terminal (OUT), and for coupling the remainder of said conversion resistors (RCNV0 - RCNV1) in between the third supply terminal (VDDH) and the output terminal (OUT). The value of said number depends on the data content of the digital signal (DS). Digital to analog converters are generally implemented in ICs. For modern ICs there is a trend toward ever decreasing supply voltages. Often circuits implemented in new IC processes have to be able to interface with ICs processed in less modern processes which are generally operated on higher supply voltages.; In the modern process, therefore, circuits designed in modern ICs have to cope with voltages which are above the maximum specification for their transistors or other components. The DA-converter (DAC) mentioned above fulfils this requirement by the fact that material, such as polycrystalline silicon, is used for the conversion resistors (RCNV2 - RCNVn), which material can cope with relatively high voltages, and furthermore by the fact that only the coupling means (CPL) have to be designed to cope with relatively high voltage

Alteration of protein expression and spliceosome pathway activity during Barrett’s carcinogenesis

Background: Barrett’s esophagus (BE) is a known precursor lesion and the strongest risk factor for esophageal adenocarcinoma (EAC), a common and lethal type of cancer. Prediction of risk, the basis for efficient intervention, is commonly solely based on histologic examination. This approach is challenged by problems such as inter-observer variability in the face of the high heterogeneity of dysplastic tissue. Molecular markers might offer an additional way to understand the carcinogenesis and improve the diagnosis—and eventually treatment. In this study, we probed significant proteomic changes during dysplastic progression from BE into EAC. Methods: During endoscopic mucosa resection, epithelial and stromal tissue samples were collected by laser capture microdissection from 10 patients with normal BE and 13 patients with high-grade dysplastic/EAC. Samples were analyzed by mass spectrometry-based proteomic analysis. Expressed proteins were determined by label-free quantitation, and gene set enrichment was used to find differentially expressed pathways. The results were validated by immunohistochemistry for two selected key proteins (MSH6 and XPO5). Results: Comparing dysplastic/EAC to non-dysplastic BE, we found in equal volumes of epithelial tissue an overall up-regulation in terms of protein abundance and diversity, and determined a set of 226 differentially expressed proteins. Significantly higher expressions of MSH6 and XPO5 were validated orthogonally and confirmed by immunohistochemistry. Conclusions: Our results demonstrate that disease-related proteomic alterations can be determined by analyzing minute amounts of cell-type-specific collected tissue. Further analysis indicated that alterations of certain pathways associated with carcinogenesis, such as micro-RNA trafficking, DNA damage repair, and spliceosome activity, exist in dysplastic/EAC.</p

A continuous-time supply-driven inventory-constrained routing problem

We address an inventory routing problem (IRP) in which routing and inventory decisions are dictated by supply rather than demand. Moreover, inventory is held in containers that act as both a storage container and a movable transport unit. This problem emanates from logistics related to biogas transportation in which biogas is transported in containers from many suppliers to a single facility. We present a novel and compact formulation for the supply-driven IRP which addresses the routing decisions in continuous-time in which inventory levels within the containers are continuous. Valid inequalities are included and realistic instances are solved to optimality. For all experiments, we found that the total transportation time is minimized when the storage capacity at each supplier is larger than or equal to the vehicle capacity. These routes are characterized by tours in which mostly single suppliers are visited. In 95% of the instances, the average content level of the exchanged containers exceeded 99.6%