Power Mitigation by Performance Equalization in a Heterogeneous Reconfigurable Multicore Architecture

This paper presents an integrated self-aware computing model mitigating the power dissipation of a heterogeneous reconfigurable multicore architecture by dynamically scaling the operating frequency of each core. The power mitigation is achieved by equalizing the performance of all the cores for an uninterrupted exchange of data. The multicore platform consists of heterogeneous Coarse-Grained Reconfigurable Arrays (CGRAs) of application-specific sizes and a Reduced Instruction-Set Computing (RISC) core. The CGRAs and the RISC core are integrated with each other over a Network-on-Chip (NoC) of six nodes arranged in a topology of two rows and three columns. The RISC core constantly monitors and controls the performance of each CGRA accelerator by adjusting the operating frequencies unless the performance of all the CGRAs is optimally balanced over the platform. The CGRA cores on the platform are processing some of the most computationally-intensive signal processing algorithms while the RISC core establishes packet based synchronization between the cores for computation and communication. All the cores can access each other’s computational and memory resources while processing the kernels simultaneously and independently of each other. Besides general-purpose processing and overall platform supervision, the RISC processor manages performance equalization among all the cores which mitigates the overall dynamic power dissipation by 20.7 % for a proof-of-concept test.     

Evolution of porosity in suspension thermal sprayed YSZ thermal barrier coatings through neutron scattering and image analysis techniques

Porosity is a key parameter on thermal barrier coatings, directly influencing thermal conductivity and strain tolerance. Suspension high velocity oxy-fuel (SHVOF) thermal spraying enables the use of sub-micron particles, increasing control over porosity and introducing nano-sized pores. Neutron scattering is capable of studying porosity with radii between 1 nm and 10 μm, thanks to the combination of small-angle and ultra-small-angle neutron scattering. Image analysis allows for the study of porosity with radii above ～100 nm. For the first time in SHVOF 8YSZ, pore size distribution, total porosity and pore morphology were studied to determine the effects of heat treatment. X-ray diffraction and micro-hardness measurements were performed to study the phase transformation, and its effects on the mechanical properties. The results show an abundant presence of nano-pores in the as-sprayed coatings, which are eliminated after heat treatment at 1100 °C; a transition from inter-splat lamellar to globular pores and the appearance of micro-cracks along with the accumulation of micro-strains associated with the phase transformation at 1200 °C.     

Structure and charge transport mechanism in hydrothermally synthesized (La<Subscript>0.5</Subscript>Ba<Subscript>0.5</Subscript>MnO<Subscript>3</Subscript>) cubic perovskite manganite

Perovskite manganites with chemical formula La_0.5Ba_0.5MnO₃ (LBMO) samples were synthesized though the hydrothermal process by heating suitable reactants at 270?°C in an autoclave for 25 h. After washing with de-ionized water several times, the as prepared samples were then calcined at different temperatures, ranging from 120 to 1000?°C to remove the impurities. Final sintering of the sample was carried out at 1350?°C for 24 h. Subsequent X-ray diffraction (XRD) measurements were also carried out. Rietveld refinement of XRD data for the sample sintered at 1350?°C confirmed single phase cubic structure with lattice parameter a?=?3.9057? and space group P m ?3 m. The dc electrical measurements were performed in a broad range of temperatures from 77 to 870 K on this sample. The focal point of this study was to obtain microscopic parameters and characteristic length in order to discuss the relationship between magnetic, electric and phonon excitations. The electrical resistivity measurements revealed a metallic/ferromagnetic to semiconductor/paramagnetic phase transition (T_C) at 339 K. In the metallic region the experimental data best fitted the resistivity equation \(\uprho (\text{T})={\uprho _{o}}+{\uprho _2}{\text{T}^2}+{\uprho _{2.5}}{\text{T}^{2.5}}+{\uprho _{4.5}}{\text{T}^{4.5}}\) showing that the resistivity effect arises due to residual impurities, grain boundaries, electron–electron (e–e), electron–magnon (e–mag) and electron–phonon (e–ph) scattering. The analysis of the resistivity data above T_C has shown a transformation in conduction mechanism from Mott’s variable range hopping (MVRH) to small polaron hopping (SPH), around 585 K. Hopping of carriers to larger distances with multiplying values of activation energies are analyzed through MVRH below 585 K. Above 585 K, the carriers were found to be trapped by several scattering centers through small polaron, this behavior having been interpreted in the light of SPH model.     

Hot deformation behavior of Cu-bearing antibacterial titanium alloy

We investigated the deformation behavior of a new biomedical Cu-bearing titanium alloy (Ti-645 (Ti-6.06Al-3.75V-4.85Cu, in wt%)) to optimize its microstructure control and the hot-working process. The results showed that true stress–true strain curve of Ti-645 alloy was susceptible to both deformation temperature and strain rate. The microstructure of Ti-645 alloy was significantly changed from equiaxed grain to acicular one with the deformation temperature while a notable decrease in grain size was recorded as well. Dynamic recovery (DRV) and dynamic recrystallization (DRX) obviously existed during the thermal compression of Ti-645 alloy. The apparent activation energies in (α?+?β) phase and β single phase regions were calculated to be 495.21?kJ?mol^?1 and 195.69?kJ?mol^?1, respectively. The processing map showed that the alloy had a large hot-working region whereas the optimum window occurred in the strain rate range of 0.001–0.1?s^?1, and temperature range of 900–960?°C and 1000–1050?°C. The obtained results could provide a technological basis for the design of hot working procedure of Ti-645 alloy to optimize the material design and widen the potential application of Ti-645 alloy in clinic.     

Enhanced Performance of MoS2 Photodetectors by Inserting an ALD‐Processed TiO2 Interlayer

2D molybdenum disulfide (MoS₂) possesses excellent optoelectronic properties that make it a promising candidate for use in high‐performance photodetectors. Yet, to meet the growing demand for practical and reliable MoS₂ photodetectors, the critical issue of defect introduction to the interface between the exfoliated MoS₂ and the electrode metal during fabrication must be addressed, because defects deteriorate the device performance. To achieve this objective, the use of an atomic layer‐deposited TiO₂ interlayer (between exfoliated MoS₂ and electrode) is reported in this work, for the first time, to enhance the performance of MoS₂ photodetectors. The TiO₂ interlayer is inserted through 20 atomic layer deposition cycles before depositing the electrode metal on MoS₂/SiO₂ substrate, leading to significantly enhanced photoresponsivity and response speed. These results pave the way for practical applications and provide a novel direction for optimizing the interlayer material.     

稻壳纤维粒径和掺量分数对水泥复合材料性能的影响

以稻壳纤维（Rice husk fiber,RHF）为增强材料,以水泥为基体,制备了RHF/水泥基复合材料。研究了粒径对RHF在水泥基体中分散性能的影响;并以RHF粒径和掺入质量比为考察因素,采用响应曲面法,以RHF/水泥基复合材料的密度、抗折强度、含水率、吸水率和导热系数为响应值,建立数学模型,对RHF/水泥基复合材料的成型工艺进行优化设计。结果表明：RHF的粒径越小,在水泥基体中分散性能越好,粒径为150 μm的RHF分散系数达到最大值,为0.981;响应曲面模型分析表明RHF的粒径为150 μm、掺入质量为水泥质量的3%时,RHF/水泥基复合材料的性能达到最优,此时RHF/水泥基复合材料的密度为1 559.26 kg/m³,抗折强度为9.38 MPa,含水率为7.05%,吸水率为16.71%,导热系数为0.50 W/（m·K）,达到了建筑行业标准JC/T 411-2007的要求。     

Intrinsic polarization and resistive leakage analyses in high performance piezo-/pyroelectric Ho-doped 0.64PMN-0.36PT binary ceramic

This paper presents in detail the ferroelectric properties of Ho-doped 0.64Pb(Mg_1/3Nb_2/3)O₃-0.36PbTiO₃ ceramic including determination of intrinsic polarization and investigation of resistive leakage. The effect of Ho³⁺ doping on the structure, dielectric, piezoelectric and ferroelectric properties of PMN-PT ceramics was studied. Perovskite phase of pure and Ho-doped 0.64Pb(Mg_1/3Nb_2/3)O₃-0.36PbTiO₃ ceramics were synthesized using solid state reaction method. Powder XRD confirmed the incorporation of Ho³⁺ ions in PMN-PT lattice. EDX spectra confirmed the existence of Ho and its homogeneity in doped-sample. The average grain size, transition temperature and dielectric loss factor (tan δ) decreased while the density and the dielectric constant of the PMN-PT ceramic increased by Ho doping. Furthermore, an increase in the ferroelectric properties and the piezoelectric coefficient (d₃₃¹, from 547 to 610?pm/V) were observed for doped sample. The ‘Remanent Hysteresis Task’ revealed that a major portion (80.42%) of the remanent polarization (P_r) is switchable in the sample which makes Ho-doped PMN-PT a potential material for memory switching devices. Time-dependent compensated (TDC) hysteresis task and fatigue test were carried out which revealed resistive leakage and fatigue free nature of Ho-doped PMN-PT ceramic. These results demonstrate that Ho-doped PMN-PT ceramic possesses excellent properties to achieve a variety of applications.     

CMOS Enabled Microfluidic Systems for Healthcare Based Applications

With the increased global population, it is more important than ever to expand accessibility to affordable personalized healthcare. In this context, a seamless integration of microfluidic technology for bioanalysis and drug delivery and complementary metal oxide semiconductor (CMOS) technology enabled data‐management circuitry is critical. Therefore, here, the fundamentals, integration aspects, and applications of CMOS‐enabled microfluidic systems for affordable personalized healthcare systems are presented. Critical components, like sensors, actuators, and their fabrication and packaging, are discussed and reviewed in detail. With the emergence of the Internet‐of‐Things and the upcoming Internet‐of‐Everything for a people–process–data–device connected world, now is the time to take CMOS‐enabled microfluidics technology to as many people as possible. There is enormous potential for microfluidic technologies in affordable healthcare for everyone, and CMOS technology will play a major role in making that happen.     

Noninvasive Featherlight Wearable Compliant “Marine Skin”: Standalone Multisensory System for Deep‐Sea Environmental Monitoring

Advances in marine research to understand environmental change and its effect on marine ecosystems rely on gathering data on species physiology, their habitat, and their mobility patterns using heavy and invasive biologgers and sensory telemetric networks. In the past, a lightweight (6 g) compliant environmental monitoring system: Marine Skin was demonstrated. In this paper, an enhanced version of that skin with improved functionalities (500–1500% enhanced sensitivity), packaging, and most importantly its endurance at a depth of 2 km in the highly saline Red Sea water for four consecutive weeks is reported. A unique noninvasive approach for attachment of the sensor by designing a wearable, stretchable jacket (bracelet) that can adhere to any species irrespective of their skin type is also illustrated. The wearable featherlight (<0.5 g in air, 3 g with jacket) gadget is deployed on Barramundi, Seabream, and common goldfish to demonstrate the noninvasive and effective attachment strategy on different species of variable sizes which does not hinder the animals' natural movement or behavior.