A Power-Gated 8-Transistor Physically Unclonable Function Accelerates Evaluation Speeds

\ua9 2023 by the authors.The proposed 8-Transistor (8T) Physically Unclonable Function (PUF), in conjunction with the power gating technique, can significantly accelerate a single evaluation cycle more than 100,000 times faster than a 6-Transistor (6T) Static Random-Access Memory (SRAM) PUF. The 8T PUF is built to swiftly eliminate data remanence and maximise physical mismatch. Moreover, a two-phase power gating module is devised to provide controllable power on/off cycles for the chosen PUF clusters in order to facilitate fast statistical measurements and curb the in-rush current. The architecture and hardware implementation of the power-gated PUF are developed to accommodate fast multiple evaluations of PUF Responses. The fast speed enables a new data processing method, which coordinates Dark-bit masking and Multiple Temporal Majority Voting (TMV) in different Process, Voltage and Temperature (PVT) corners or during field usage, hence greatly reducing the Bit Error Rate (BER) and the hardware penalty for error correction. The designs are based on the UMC 65 nm technology and aim to tape out an Application-Specific Integrated Circuit (ASIC) chip. Post-layout Monte Carlo (MC) simulations are performed with Cadence, and the extracted PUF Responses are processed with Matlab to evaluate the 8T PUF performance and statistical metrics for subsequent inclusion in PUF Responses, which comprise the novelty of this approach

Dissociative recombination and electron-impact de-excitation in CH photon emission under ITER divertor-relevant plasma conditions

For understanding carbon erosion and redeposition in nuclear fusion devices, it is important to understand the transport and chemical break-up of hydrocarbon molecules in edge plasmas, often diagnosed by emission of the CH A^2\Delta - X^2\Pi Ger\"o band around 430 nm. The CH A-level can be excited either by electron-impact or by dissociative recombination (D.R.) of hydrocarbon ions. These processes were included in the 3D Monte Carlo impurity transport code ERO. A series of methane injection experiments was performed in the high-density, low-temperature linear plasma generator Pilot-PSI, and simulated emission intensity profiles were benchmarked against these experiments. It was confirmed that excitation by D.R. dominates at T_e < 1.5 eV. The results indicate that the fraction of D.R. events that lead to a CH radical in the A-level and consequent photon emission is at least 10%. Additionally, quenching of the excited CH radicals by electron impact de-excitation was included in the modeling. This quenching is shown to be significant: depending on the electron density, it reduces the effective CH emission by a factor of 1.4 at n_e=1.3*10^20 m^-3, to 2.8 at n_e=9.3*10^20 m^-3. Its inclusion significantly improved agreement between experiment and modeling

Dust remobilization in fusion plasmas under steady state conditions

The first combined experimental and theoretical studies of dust remobilization by plasma forces are reported. The main theoretical aspects of remobilization in fusion devices under steady state conditions are analyzed. In particular, the dominant role of adhesive forces is highlighted and generic remobilization conditions - direct lift-up, sliding, rolling - are formulated. A novel experimental technique is proposed, based on controlled adhesion of dust grains on tungsten samples combined with detailed mapping of the dust deposition profile prior and post plasma exposure. Proof-of-principle experiments in the TEXTOR tokamak and the EXTRAP-T2R reversed-field pinch are presented. The versatile environment of the linear device Pilot-PSI allowed for experiments with different magnetic field topologies and varying plasma conditions that were complemented with camera observations.Comment: 16 pages, 11 figures, 3 table

NMR solution conformation of gramicidin A double helix

AbstractThe conformation of species 3 of Val-gramicidin A in dioxane has been determined by two-dimensional NMR spectroscopy. It is presented by the left handed ⇅ππ5.6LD double helix, a suitable model of an ion permeable pore across the membrane matrix

Chiral peculiar properties of self-organization of diphenylalanine peptide nanotubes: Modeling of structure and properties

The structure and properties of diphenylalanine peptide nanotubes based on phenylalanine were investigated by various molecular modeling methods. The main approaches were semi-empirical quantum-chemical methods (PM3 and AM1), and molecular mechanical ones. Both the model structures and the structures extracted from their experimental crystallographic databases obtained by X-ray methods were examined. A comparison of optimized model structures and structures obtained by naturally-occurring self-assembly showed their important differences depending on D- and L-chirality. In both the cases, the effect of chirality on the results of self-assembly of diphenylalanine peptide nanotubes was established: peptide nanotubes based on the D-diphenylalanine (D-FF) has high condensation energy E 0 in transverse direction and forms thicker and shorter peptide nanotubes bundles, than that based on L-diphenylalanine (L-FF). A topological difference was established: model peptide nanotubes were optimized into structures consisting of rings, while naturally self-assembled peptide nanotubes consisted of helical coils. The latter were different for the original L-FF and D-FF. They formed helix structures in which the chirality sign changes as the level of the macromolecule hierarchy raises. Total energy of the optimal distances between two units are deeper for L-FF (-1.014 eV) then for D-FF (-0.607 eV) for ring models, while for helix coil are approximately the same and have for L-FF (-6.18 eV) and for D-FF (-6.22 eV) by PM3 method; for molecular mechanical methods energy changes are of the order of 2-3 eV for both the cases. A topological transition between a ring and a helix coil of peptide nanotube structures is discussed: self-assembled natural helix structures are more stable and favourable, they have lower energy in optimal configuration as compared with ring models by a value of the order of 1 eV for molecular mechanical methods and 5 eV for PM3 method. © 2019 Mathematical Biology and Bioinformatics.Part of this work was developed as part of the CICECO-Aveiro Materials Institute project, POCI-01-0145-FEDER-007679 funded from Fundação para a Ciência e a Tecnologia (FCT) Ref. UID/CTM/50011/2013, and funded from national funds through FCT/MEC, and co-funded by FEDER in accordance with the PT2020 Partnership Agreement. P.Z. thanks the project FCT PTDC/QEQ-QAN/6373/2014. S.K. thanks the project FCT PTDC/CTM-CTM/31679/2017

Использование графических процессоров в задачах, не связанных с графикой

Графические процессоры были созданы для того, чтобы ускорять обработку и отображение компьютерной графики. Современная архитектура графических процессоров не только позволяет быстрее рассчитывать графику, но также эффективно взаимодействовать с большими объёмами данных. Целью данной работы является проведение анализа работы графических ускорителей в различных задачах, а также проведение сравнительного анализа архитектур графических процессоров на примере CUDA с центральными процессорами на примере x64.Graphical Processing Units are made to speed up calculations of computer graphics. Modern GPU`s architecture allows not only calculating graphics, but also working on tasks for general computing. The main target of this paper is to analyze GPU`s performance in different tasks and to compare GPU`s CUDA architecture with standard CPU`s x86-64 architecture

Erosion yields of carbon under various plasma conditions in Pilot-PSI

Fine-grain graphite targets have been exposed to ITER divertor relevant plasmas in Pilot-PSI to address material migration issues in fusion devices. Optical emission spectroscopy and mass loss measurements have been employed to quantify gross chemical erosion and net erosion yields, respectively. Effects of the ion impact energy and target geometry on carbon erosion yields have been studied. It is concluded that temporal evolution of gross chemical erosion is strongly connected with changes in morphology of plasma exposed surfaces. The net carbon erosion yield is increased when the targets are partly covered by insulating boron-nitride rings.Comment: 14 pages, 4 figures, Contribution to the 19th International Conference on Plasma Surface Interaction