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Reduction to satisfiability of constrained Horn clauses (CHCs) is a widely studied approach to automated program verification. Current CHC-based methods, however, do not work very well for pointer-manipulating programs, especially those with dynamic memory allocation. This article presents a novel reduction of pointer-manipulating Rust programs into CHCs, which clears away pointers and memory states by leveraging Rust’s guarantees on permission. We formalize our reduction for a simplified core of Rust and prove its soundness and completeness. We have implemented a prototype verifier for a subset of Rust and confirmed the effectiveness of our method.

This research evaluates the influence of phase fluctuation of a high-speed smart gear on the return loss of monitoring antenna in our developing “smart gear sensor system”. This smart health monitoring system of gear comprising of an antenna connected to a network analyer and another similar antenna integrating crack detection sensors directly printed on a gear. The principle of this system is based on magnetic coupling phenomenon between samples of antenna and crack detection sensors with antenna printed on polyacetal (POM) plates so that the characteristics of the gear side elements can be obtained wirelessly. In this paper, the effect of the relative phase fluctuation when the smart gear is operating at high speed on this coupling signal perhaps is considered. Practically, a special experimental rig consists of a motor with a speed control button, an antenna on a polyacetal (POM) plate with a radio frequency connector, and a smart gear with integrated sensors antenna was created. Thanks to this test rig, the smart gear is able to rotate with variant rotational velocities in range of 500 rpm to 5000 rpm while keeping pairing concentrically with the fixed monitoring antenna at a constant distance. Then, return losses received from this antenna via the network analyzer then are recorded at each specific speed. In comparison with the return losses gained in case of similar experimental setting but in stationary state, the shape form of the high-speed phase fluctuation return loss is indicated.

CFRP is a composite material composed of carbon fiber and resin. CFRP is commonly applied to the aerospace industry which requires lightweight and intensity. Thanks to superior formability of CFRP, we can form shape of Wolter-1 optics, which consists of paraboloid and hyperboloid, to a monolithic substrate. Since the surface roughness of a CFRP substrate is a few µm, we have to make the smooth surface for reflecting X-rays on the CFRP substrate. We have developed a new method of shaping the reflective surface instead of the replica method used in lightweight X-ray mirrors such as Astro-H. In the new method, the reflective surface is formed by pasting thin sheet-glasses with 100 µm thick onto the CFRP substrate. The thin sheet-glass has a surface roughness about 0.4 nm as measured by Zygo. We fabricated a CFRP mirror pasting thin sheet-glasses, and then coated tungsten on the mirror in June 2020. The figure error (s) of the CFRP mirror was achieved to be about 1-2 μm by stacking the CFRP mirror on the housing module. X-ray imaging quality of the CFRP mirror was measured at Spring-8 in July 2020. The half-power diameter of the CFRP mirror was estimated to be about 150 arcsec, which was nearly equal to the prediction from a distribution of the slope error deduced from the surface profile. We describe a future plan to improve the image quality of the CFRP mirror.

A wireless inductive coupling ThruChip Interface (TCI) is a flexible system-in-package (SiP) technique which enables to build a powerful interconnection network between stacked chips. For easy use of TCI, we have developed intellectual properties (IPs), and proposed an interconnection network which can make the use of IPs. We also developed a real chip embedded the IP, and evaluated the performance. By stacking multiple chips with the proposed IP, an inter-chip network with link-to-link flow control by piggyback control is established. The new proposed escalator network which uses piggyback of the credit packets outperforms the ring network used in the first prototype by 28%-59% in terms of throughput. The performance overhead by the piggyback control was less than 3%-4% of that without control messages.

VPCMA (Variable Pipelined Cool Mega Array) is a low power CGRA (Coarse-Grained Reconfigurable Architecture) which we previously proposed in [1]. CC-SOTB2 is a real chip implementation of the VPCMA using Renesas 65-nm SOTB technology [2]. In this demonstration, we will show the power consumption of the CC-SOTB2 while performing a real image processing.

Body biasing can be used to control the leakage power and the performance of transistors by changing the threshold voltage after fabrication. Especially, a new process called Silicon-On-Thin BOX (SOTB) CMOS can control the balance of these two factors. When it is applied to a Coarse-Grained Reconfigurable Array (CGRA), the leakage power can be largely reduced by controlling precisely the bias with small domain size. On the other hand, the choices on bias voltages depend on the application executed on the platform, especially its mapping. In this paper, we propose to apply a multi-objective optimization for the application mapping and the body bias control on an energy efficient CGRA called CC-SOTB (Cool Mega Array Cube-SOTB). By using an NSGA-II algorithm for the mapping exploration and Integer Linear Programming (ILP) for the body bias control optimization, we show that it is possible to achieve better power consumption results than in previous works. For instance, in the case of a domain size of 2 rows by 1 column, it is possible to achieve a power reduction ratio up to 43.25%, compared to 21.09% previously, for the studied application. This is however achieved at the cost of a bigger mapping width. Nonetheless, the exploration allows to have finer analyses about both mapping and consumption. Indeed, these promising results show that optimizing the application mapping simultaneously with the body bias control can provide more interesting results, giving deeper quantitative information about trade-off possibilities.

This paper explores the grain of domain size of an energy efficient coarse grained reconfigurable array called CMA (Cool Mega Array). By using Genetic Algorithm based body bias assignment method, the leakage reduction of various grain size was evaluated. As a result, a domain with 2×1 PEs achieved about 40% power reduction with a 6% area overhead.

We synthesized amorphous films composed of transition-metal-encapsulating Si clusters ( M Si n : M = Zr, Nb, Mo and W) by deposition of hydrogenated M Si n H x clusters onto solid substrates followed by annealing at 400–500 °C for dehydrogenation. The M Si n ( n = 7–20) cluster films are amorphous semiconductors with an optical gap > 0.4 eV and have larger electron and hole mobility than that of the hydrogenated amorphous Si (a-Si:H) film. In these films, while Si atoms form amorphous networks similar to those in a-Si:H films, the thermal stability is enhanced and the electronic disorder is reduced by the use of M Si n clusters as the unit structures. Structure modeling by ab initio calculations for M Si n films suggests that the encapsulated M atom works as a terminator of dangling bonds of the Si network.

The nitrile hydratase (NHase) from Rhodococcus sp. N-771 is a photoreactive enzyme that is inactivated on nitrosylation of the non-heme iron center and activated on photo-dissociation of nitric oxide (NO). The nitrile hydratase operon consists of six genes encoding NHase regulator 2, NHase regulator 1, amidase, NHase alpha subunit, NHase beta subunit and NHase activator. We overproduced the NHase in Escherichia coli using a T7 expression system. The NHase was functionally expressed in E. coli only when the NHase activator encoded downstream of the beta subunit gene was co-expressed and the transformant was grown at 30 degrees C or less. A ligand cysteine, alphaCys112, of the recombinant NHase was also post-translationally modified to a cysteine-sulfinic acid similar to for the native NHase. Although another modification of alphaCys114 could not be identified because of the instability under acidic conditions, the recombinant NHase could be reversibly inactivated by nitric oxide.

We synthesized amorphous semiconductor films composed of Mo-encapsulating Si clusters (MoSin : n∼10) on solid substrates. The MoSi10 films had Si networks similar to hydrogenated amorphous Si and an optical gap of 1.5 eV. Electron spin resonance signals were not observed in the films indicating that dangling bonds of Si were terminated by Mo atoms. We fabricated thin-film-transistors using the MoSi10 film as a channel material. The electric field effect of the film was clearly observed. This suggests that the density of mid-gap states in the film is low enough for the field effect to occur.

Ion chromatography of sulfide, sulfite, sulfate and thiosulfate in a mixture is often difficult because of instability of sulfide and sulfite, poor separation of sulfide from common anions such as bromide or nitrate and similar elution-times for sulfite and sulfate. An ion-pair chromatographic method for the determination of these sulfur anions has been established by stoichiometric conversion of sulfide and sulfite into stable thiocyanate and sulfate, respectively, prior to the chromatographic run. Sulfate, thiosulfate and thiocyanate were resolved on an octadecylsilica column with an acetonitrile-water mobile phase containing tetrapropylammonium salt (TPA) as an ion-paring reagent, and thiosulfate and thiocyanate in the effluent could be measured with a photometric detector (220 nm) and sulfate with a suppressed conductivity detector. When an acetonitrile-water (6:94, v/v) mobile phase (pH 5.0) containing 15 mM TPA and small amounts of acetic acid was used at a flow-rate of 0.6 ml min(-1), the three anions could be eluted within 32 min. Calibration plots of peak height versus concentration for sulfide (detected as thiocyanate) and thiosulfate gave straight lines up to 35 and 60 microM, respectively. The calibration plot for sulfide coincided with that obtained by using thiocyanate. A calibration plot for sulfite, measured as sulfate, was also linear up to 135 microM and was in accord with that of sulfate. Each calibration plot gave a correlation coefficient greater than 0.999. For six replicates obtained for a mixture of 30.0 microM sulfide, 50.0 microM sulfite, 50.0 microM sulfate and 20.0 microM thiosulfate, the proposed method gave a mean value of 30.1 microM with a standard deviation (SD) of 0.77 microM and a relative standard deviation (RSD) of 2.6% for sulfide, 101 microM (SD = 3.5 microM, RSD = 3.5%) for the total of sulfite and sulfate and 20.1 microM (SD = 0.44 microM, RSD = 2.2%) for thiosulfate. Recoveries for sulfide, sulfite plus sulfate, and thiosulfate in hot-spring water samples using the proposed method were found to be quantitative.

We synthesized amorphous films composed of transition-metal-encapsulating Si clusters (MSin: M=Mo or Nb) by deposition of hydrogenated MSinHx clusters onto silica substrates followed by annealing at 500 ?C for dehydrogenation. The MoSin (n=7?16) cluster films are semiconductors with an optical gap >0.6 eV and resistivity >1 ? cm. In particular, the MoSi12 cluster film has a large gap of 1.1 eV and resistivity of 120 ? cm with high hole mobility of 32 cm2/(V s). In these films, Si atoms form amorphous networks similar to those in hydrogenated amorphous Si but the electronic disorder is reduced by the use of MSin clusters as the building blocks.