A 14-bit dual-path 2-0 MASH ADC with dual digital error correction

A dual-path 2-0 cascaded delta-sigma (MASH) ADC was implemented with fast digital correction of both DAC errors and MASH mismatch errors. The digital correction techniques greatly reduced the requirements on the analog circuits. The dual-path structure allows fast convergence and improved accuracy for the correction. Using a 20 MHz clock, the prototype chip achieved an 84 dB dynamic range in a 1.25 MHz signal band, when fabricated in CMOS 0.18 μm process.     

Mode selection schemes for unicasting device‐to‐device communications supported by network coding

Device‐to‐device (D2D) communication in a cellular spectrum increases the spectral and energy efficiency of local communication sessions, while also taking advantage of accessing licensed spectrum and higher transmit power levels than when using unlicensed bands. To realize the potential benefits of D2D communications, appropriate mode selection algorithms that select between the cellular and D2D communication modes must be designed. On the other hand, physical‐layer network coding (NWC) at a cellular base station—which can be used without D2D capability—can also improve the spectral efficiency of a cellular network that carries local traffic. In this paper, we ask whether cellular networks should support D2D communications, physical‐layer NWC, or both. To this end, we study the performance of mode selection algorithms that can be used in cellular networks that use physical‐layer NWC and support D2D communications. We find that the joint application of D2D communication and NWC scheme yields additional gains compared with a network that implements only one of these schemes, provided that the network implements proper mode selection and resource allocation algorithms. We propose 2 mode selection schemes that aim to achieve high signal‐to‐interference‐plus‐noise ratio and spectral efficiency, respectively, and take into account the NWC and D2D capabilities of the network.     

Operation and Control of a Full-Scale Biogas Plant Treating Wastewater from the Cleaning of Car Tanks

A 1200-m³ full-scale biogas plant treating highly polluted wastewater (WW) from the cleaning of tank cars transporting food and fodder is working stably and efficiently despite the WW is constantly varying in strength and composition, is easily acidifying, and low in alkalinity. Na₂CO₃ has to be added to maintain the digester alkalinity and the digester pH at defined values due to softened water used for car tank cleaning. Monitoring volatile organic acid concentration and controlling the alkalinity in the digester are essential for maintaining the digestion process stability. Biogas production is adapted to the demand by a modulated feeding regime. The drastic modulation of feeding is possible due to the moderate organic loading of the plant along with the high average hydraulic retention time.     

Interaction of TLR4 and TLR8 in the Innate Immune Response against Mycobacterium Tuberculosis

The interaction and crosstalk of Toll-like receptors (TLRs) is an established pathway in which the innate immune system recognises and fights pathogens. In a single nucleotide polymorphisms (SNP) analysis of an Indian cohort, we found evidence for both TLR4-399T and TRL8-1A conveying increased susceptibility towards tuberculosis (TB) in an interdependent manner, even though there is no established TLR4 ligand present in Mycobacterium tuberculosis (Mtb), which is the causative pathogen of TB. Docking studies revealed that TLR4 and TLR8 can build a heterodimer, allowing interaction with TLR8 ligands. The conformational change of TLR4-399T might impair this interaction. With immunoprecipitation and mass spectrometry, we precipitated TLR4 with TLR8-targeted antibodies, indicating heterodimerisation. Confocal microscopy confirmed a high co-localisation frequency of TLR4 and TLR8 that further increased upon TLR8 stimulation. The heterodimerisation of TLR4 and TLR8 led to an induction of IL12p40, NF-κB, and IRF3. TLR4-399T in interaction with TLR8 induced an increased NF-κB response as compared to TLR4-399C, which was potentially caused by an alteration of subsequent immunological pathways involving type I IFNs. In summary, we present evidence that the heterodimerisation of TLR4 and TLR8 at the endosome is involved in Mtb recognition via TLR8 ligands, such as microbial RNA, which induces a Th1 response. These findings may lead to novel targets for therapeutic interventions and vaccine development regarding TB.     

Structure, reactivity, and mobility of carbonaceous overlayers during olefin hydrogenation on platinum and rhodium single crystal surfaces

The hydrogenation of olefins (ethylene, propylene, and isobutene) and a cyclic olefin (cyclohexene) has been characterized on platinum and rhodium single crystal surfaces under conditions ranging from ultrahigh vacuum (UHV) to elevated pressures. A carbonaceous overlayer, formed by C–H bond activation, exists on the metal surface during catalytic hydrogenation, and the structure of this overlayer has been characterized using sum frequency generation (SFG) vibrational spectroscopy. The dehydrogenated carbonaceous species are unreactive even in the presence of excess hydrogen, while the intermediates that turnover are weakly bonded to the metal surface. The formation of this carbonaceous overlayer is accompanied by a restructuring of the metal surface. The overlayer is mobile on the surface during hydrogenation, as shown by high pressure scanning tunneling microscopy (HP-STM) results. Coadsorbed CO induces ordered surface structures, and as a consequence poisons the reaction.     

Medical image reconstruction,processing, visualization,and analysis: the MIPG perspective. Medical Image Processing Group

In this paper, we identify and describe the key ideas, concepts and software related to Medical Imaging that emerged from our research group, which is commonly known by the acronym MIPG, denoting Medical Image Processing Group. For the purpose of our presentation, we consider the entire discipline of Medical Imaging to consist of the areas of acquisition, postprocessing, evaluation, and application. We are indeed fortunate to be able to discuss seminal research from our group in each of these areas. In Section II, we identify relevant moments of inception and describe our past contributions. Our achievements, current activities, and future directions are summarized in Section III, Section IV, and Section V, respectively; the keys to our success are listed in Section V     

A particle swarm approach for grinding process optimization analysis

Optimization is necessary for the control of any process to achieve better product quality, high productivity with low cost. The grinding of silicon carbide is not an easy task due to its low fracture toughness, therefore making the material sensitive to cracking. The efficient grinding involves the optimal selection of operating parameters to maximize the material removal rate (MRR) while maintaining the required surface finish and limiting surface damage. In this work, optimization based on the available model has been carried out to obtain optimum parameters for silicon carbide grinding via particle swarm optimization (PSO) based on the objective of maximizing MRR with reference to surface finish and damage. Based on statistical analysis for various constraint values of surface roughness and number of flaws, simulation results obtained for this machining process for PSO are comparatively better to genetic algorithm (GA) approach. In addition, the post-optimal robustness of PSO has also been studied. From simulation results together with the proposed robustness measurement method, it has been shown that PSO is a convergent stable algorithm.