Anti-BlUFf: towards counterfeit mitigation in IC supply chains using blockchain and PUF

International Journal of Information Security - The complexity of today’s integrated circuit (IC) supply chain, organised in several tiers and including many companies located in different...     

Room temperature response and enhanced hydrogen sensing in size selected Pd-C core-shell nanoparticles: Role of carbon shell and Pd-C interface

In the present work, the effect of carbon shell around size selected palladium (Pd) nanoparticles on hydrogen (H₂) sensing has been studied by investigating the sensing response of Pd-C core-shell nanoparticles having a fixed core size and different shell thickness. The H₂ sensing response of sensors based on Pd and Pd-C nanoparticles deposited on SiO₂ and graphene substrate has been measured over a temperature range of 25 °C–150 °C. It is observed that Pd-C nanoparticle sensor shows higher sensitivity with increase in shell thickness and faster response/recovery in comparison to that of Pd nanoparticle samples. Pd-C nanoparticles show room temperature H₂ sensitivity in contrast to Pd nanoparticles which respond only at higher temperatures. Role of carbon shell is also understood by investigating H₂ sensing properties of Pd and Pd-C nanoparticles on graphene substrates. These results show that higher catalytic activity and electronic interaction at Pd-C interface, a complete coverage and protection of Pd surface by carbon and presence of structural defects in nanoparticle core are important for room temperature and higher sensing response.     

Room temperature hydrogen gas sensors of functionalized carbon nanotubes based hybrid nanostructure: Role of Pt sputtered nanoparticles

Fast detection of H₂ gas at room temperature has constantly remained a challenge. The metal-oxide based gas sensors have shown excellent sensing properties for gases like H₂, NO, CO and NH₃. In the present work, the H₂ gas sensing characteristics of multiwalled carbon nanotubes based hybrid sensor (F-MWCNTs/TiO₂/Pt) has been reported. The fabricated sensor shows 3.9% sensitivity for low concentration i.e. 0.05% of H₂ with good repeatability and stability at room temperature. The sensing response of F-MWCNTs/TiO₂/Pt is interrelated to change in their resistance on the introduction of H₂ gas and this phenomenon is required for deep understanding the effect of H₂ adsorption on their electronic conduction. The improvement in sensitivity of F-MWCNTs/TiO₂/Pt as compared to MWCNTs/TiO₂ towards H₂ is because of the catalytic role of dispersed Pt nanoparticles deposited by sputtering.     

The Minimum Weight Dominating Set Problem for Permutation Graphs Is in NC

In this paper, we show that the problem of finding a minimum weight dominating set in a permutation graph, where a positive weight is assigned to each vertex, is in NC by presenting an O(log n) parallel algorithm with polynomially many processors on the CRCW model.     

Quick and reliable estimation of BOD load of beverage industrial wastewater by developing BOD biosensor

An amperometric biosensor for determination of biochemical oxygen demand in wastewater has been developed to overcome the time consuming monitoring procedures. The performance and stability of the immobilized membrane have been investigated at 37 °C and pH 6.8. Immobilized microbial membranes maintain their stability and activity after intermittent use for 400 cycles when stored at 4 °C in sodium phosphate buffer pH 6.8. The response time of the BOD sensor was only 90 min, being independent of the concentration, and the lower detection limit was 1 mg/l. The obtained BOD values showed correlation with that of the conventional method for BOD determination (BOD5) with a deviation of ±10%. Moreover, the sensor exhibits good repeatability (3.39–4.45%) and reproducibility (1.85–2.25%). Software was added to upgrade this sensor and to make it a promising candidate for online monitoring.     

Multiphase and multicomponent transport with phase change during meat cooking

A multiphase model based on unsaturated flow in a hygroscopic porous medium, which accounts for the important physical phenomena that take place during thermal treatment of meat, is developed. Frozen meat is considered as a porous solid comprising of water, fat and protein with gas trapped in its pores. As it is heated, water and fat melt, and, are gradually released from the solid protein matrix to the pore space. With further rise in temperature, liquid water evaporates. Since four fluid components (liquid water phase, liquid fat phase, water vapor and air) are present in the pore space, a mass balance equation is written for each component. Local thermal equilibrium assumption leads to one energy balance equation for the whole system. The model is validated for double-sided contact heating of hamburger patties by comparing temperature and moisture profiles with experimental studies. Dominant modes of transport are identified.     

A safer and more effective treatment regimen for eclampsia

The purpose of our investigation was twofold: to provide normative data for the ratios between head circumference and cerebellum, abdominal circumference and cerebellum, and femur length and cerebellum; and to evaluate the predictive accuracy of an abnormal ratio in the detection of growth retardation and macrosomia. Data on 675 women with normal gestations between 14 and 42 weeks were used to estimate reference curves for the three ratios to be evaluated. We then compared the ratios of 34 fetuses with intrauterine growth retardation and 28 macrosomic fetuses to the control group. Of the three ratios that we investigated, abdominal circumference to transverse cerebellar diameter was the most efficacious. However, the sensitivity of this ratio for the detection of intrauterine growth retardation and macrosomia was only 52.9% and 46.6%, respectively. A ratio between head circumference, abdominal circumference, or femur length and the transverse cerebellar diameter cannot reliably distinguish between normally growing fetuses and those that are growth retarded or macrosomic.     

Ring, torus and hypercube architectures/algorithms for parallel computing

This paper provides a survey of both architectural and algorithmic aspects of solving problems using parallel processors with ring, torus and hypercube interconnection.     

Transport in deformable food materials: A poromechanics approach

A comprehensive poromechanics-based modeling framework that can be used to model transport and deformation in food materials under a variety of processing conditions and states (rubbery or glassy) has been developed. Simplifications to the model equations have been developed, based on driving forces for deformation (moisture change and gas pressure development) and on the state of food material for transport. The framework is applied to two completely different food processes (contact heating of hamburger patties and drying of potatoes). The modeling framework is implemented using total Lagrangian mesh for solid momentum balance and Eulerian mesh for transport equations, and validated using experimental data. Transport in liquid phase dominates for both the processes, with hamburger patty shrinking with moisture loss for all moisture contents, while shrinkage in potato stops below a critical moisture content.     

Modeling of Multiphase Transport during Drying of Honeycomb Ceramic Substrates

Multiphase transport model to simulate drying of honeycomb ceramic substrates in a conventional (hot air) drier is developed. Heat and moisture transport in the honeycomb walls as well as channels is modeled. The model predictions are validated against experiments done for drying of cylinder-shaped substrates by comparing histories and axial profiles of moisture loss and point temperature histories at various locations. Drying experiments are performed at two different values of air temperature, 103°C and 137°C, at a relative humidity value of 5%. Sensitivity analysis reveals that the drying process is controlled by heat and water vapor transport. External heat transfer is the dominant resistance mechanism for energy transport, whereas internal convection and binary diffusion dominate the resistance to vapor transport.