Special Ring Research Articles

Algebraic tools in autotuning design

Autotuners represent a combination of a relay feedback identification test and some control design method. In this contribution, models with up to three parameters are estimated by means of a single asymmetrical relay experiment. Then a stable low order transfer function with a time delay term is identified by a relay experiment. Autotuning principles then combine asymmetrical relay feedback tests with a control synthesis. Two algebraic control syntheses then are presented in this paper. The first one is based on the ring of proper and stable rational functions RPS. The second one utilizes a special ring RMS, a set of RQ-meromorphic functions. In both cases, controller parameters are derived through a general solution of a linear Diophantine equation in the appropriate ring. A final controller can be tuned by a scalar real parameter m>0. The presented philosophy covers a generalization of PID controllers and the Smith-like control structure. This contribution deals with the implementation of proposed autotuners and presents some illustrative examples.

Research on Key Technologies for the Static Measurement of Railway Track Smoothness.

In this study, a static railway track smoothness detection system based on laser reference, which can measure various track smoothness parameters by using multiple sensors, is proposed. Furthermore, in order to improve the measurement accuracy and stability of the system, this paper also conducted three key analyses based on the static track measurement system. By using a liquid double-wedge automatic compensation device to compensate the horizontal angle of the beam, a mathematical model of liquid double-wedge automatic compensation was established. Then, by using an optical ring grating system to ring-grate and characterize the laser spot, the collimation efficiency of the system was improved when measuring at long distances. For the special ring grating spot image, an adaptive image processing algorithm was proposed, which can achieve sub-pixel-level positioning accuracy. This study also conducted a field measurement experiment, comparing the experimental data obtained via the static track measurement system with the results of existing track measurement products, and verifying that the static track measurement system has high measurement accuracy and stability.

Engineered DNAzyme Enables Homogeneous Detection of Cereulide via Polychromic Fluorescence Modality.

Cereulide, the exotoxin of emetic Bacillus cereus, has garnered considerable attention due to its capacity to produce foodborne poisonings and great chemical stability. Herein, a G-quadruplex-hemin DNAzyme-based biosensor was developed to detect cereulide in the homogeneous solution. Due to the special ring structure and high affinity to K+, cereulide can be attracted and intercalated into the G-quadruplex; thus, the properties of the G4 DNAzyme can be altered. The melting temperature (Tm) of the G4 DNAzyme in the presence or absence of cereulide was 58.75 and 50.10 °C, respectively, proving the intercalation of cereulide into the G4 DNAzyme. By using the polychromic fluorescence modality of CdTe quantum dots and o-phenylenediamine to assess the variation in the catalytic activity of the DNAzyme, the intercalation of cereulide had bidirectional effects in G4 DNAzyme-mediated reactions, showing that the fluorescence intensity of CdTe quantum dots displayed a linear relationship with the concentration of cereulide from 0.16 to 40 μg/mL with the limit of detection (LOD) of 0.10 μg/mL, while the fluorescence intensity of DAP exhibited a linear relationship with the concentration of cereulide from 0.02 to 40 μg/mL with the LOD of 0.01 μg/mL. It will be a perspective step of controlling cereulide as a hazardous material in food or the environment.

Effects of temperatures on microstructure evolution and deformation behavior of Fe–32Ni by in-situ EBSD

Fe–32Ni alloy has attracted the attention of researchers owing to its excellent thermal expansion properties and mechanical properties. In this study, the macroscopic mechanical properties, surface morphology, crystal orientation, evolution of grain boundary and kernel average misorientation (KAM) and deformation mechanism of Fe–32Ni alloy were systematically investigated by in-situ loading equipment from 25 °C to 800 °C combined with electron backscatter diffraction (EBSD). The results showed that the grains with (111) and (101) orientations formed a special ring texture in {100} and {110} poles of the polar diagram after grain deformation and rotation. The rotational ability of the grains with (111) and (101) orientations were significantly promoted as the temperature increased. The number and proportion of low-angle grain boundaries (LAGBs) increased with increasing strain and temperature. By analyzing the microstructure evolution during in-situ EBSD testing, it was found that the rotation of the crystals significantly improved the deformability of the material. The effect of selective passage for dislocations by LAGBs both enhanced the plasticity and caused hardening of the material. Dislocations tended to accumulate at grain boundaries causing strain concentration. Cracks sprouted at grain boundaries and expand along the grain boundaries. This study can provide profound insights on the deformation mechanism of Fe–32Ni alloy for the possible design and process optimization.

Self‐assembly of surfactin‐like polymer in solution by the dissipative particle dynamics method

AbstractSurfactin is a kind of special and efficient cyclic lipopeptide biosurfactant, which is composed of a seven‐peptide ring and a fatty acid tail chain and is widely used in the fields of medicine, environmental remediation and heavy oil transportation. This special ring structure also makes surfactin have great application potential in biomedicine and surface catalysis. In this work, the self‐assembly behavior of surfactin‐like polymer in selective solvents was studied by dissipative particle dynamics. By changing the interaction parameters, the size of the hydrophilic ring, the length of the hydrophobic tail chain and the concentration, a series of structures such as vesicles, disk‐like micelles, worm‐like micelles, sphere‐like micelles and ring‐like micelles were obtained from the establishment of the phase diagram. We explored the dynamic formation paths of vesicles and ring‐like micelles and discovered morphological changes during their aggregation. The mechanism of sphere‐like micelle formation at lower concentration was also studied, explained by the packing of molecules of effective conical shape. The structural properties of the vesicles were also intensively studied. Based on the special ring structure of surfactin‐like polymers, we explored the difference in their self‐assembly behavior from those of linear block copolymers and giant surfactant‐like polymers. A detailed study on the self‐assembly of surfactin‐like polymer can deepen the understanding of ordered aggregates of cyclic surfactants in selective solvents and can drive important implications for their practical application. © 2023 Society of Industrial Chemistry.

Some improvements for the algorithm of Gröbner bases over dual valuation domain

<abstract><p>As a special ring with zero divisors, the dual noetherian valuation domain has attracted much attention from scholars. This article aims at to improve the Buchberger's algorithm over the dual noetherian valuation domain. We present some criterions that can be applied in the algorithm for computing Gröbner bases, and the criterions may drastically reduce the number of S-polynomials in the course of the algorithm. In addition, we clearly demonstrate the improvement with an example.</p></abstract>

国内外超大直径特种环件材料对比分析

国内外超大直径特种环件材料对比分析

The Decomposition of a Finitely Generated Module over Some Special Ring

This research aims to give the decompositions of a finitely generated module over some special ring, such as the principal ideal domain and Dedekind domain. One of the main problems with module theory is to analyze the objects of the module. This research was using a literature study on finitely generated modules topics from scientific journals, especially those related to the module theory. And by selective cases we find a pattern to build a conjecture or a hypothesis, by deductive proof, we prove the conjecture and state it as a theorem. The main result in this study is the decomposition of the finitely generated module is a direct sum of the torsion submodule and torsion-free submodule. Since the torsion-free module is always a free module over a principal ideal domain, then the torsion-free submodule is a free module. Last, we generalize the ring, from a principal ideal domain, to a Dedekind domain. We found then the torsion-free submodule became a projective module. Then the decomposition of the finitely generated module is a direct sum of the torsion submodule and the projective submodule. These results should help the researchers to analyze the objects on module theory.

θ-Al2O3/FeO1.25 possessing a special ring complex of FeII---HO===FeIII for the efficient catalytic semi-hydrogenation of acetylene under front–end conditions

Herein, we pioneered that half-reduced Fe2O3 supported on θ-Al2O3 (θ-Al2O3/FeO1.25-6%-500-450) is capable of the complete removal of acetylene (0.7 vol%), achieving 82% selectivity for ethylene under front–end conditions. Corresponding characterizations demonstrate that θ-Al2O3/FeO1.25-6%-500-450 can efficiently dissociate H2 and possesses both an appropriate adsorption capacity of acetylene and desorption capacity of ethylene, due to the presence of a special ring complex of FeIII, FeII, and hydroxyl groups (FeII---HO===FeIII). Crucially, θ-Al2O3/FeO1.25-6%-500-450 displays both excellent semi-hydrogenation performance and stability on a 750 mL industrial side-line device at Lanzhou Petrochemical Company.

Head related transfer function measurements of common PPE

Due to COVID 19, personal protective equipment (PPE) is now used in everyday life. Such PPE affects communication and perception. This paper provides an overview of the impact of PPE on Head Related Transfer Functions (HRTF's). Spatial acoustic effects of common PPE on human hearing can be documented to improve and inform field worker safety and communication. After a general description of the measurement process and required tools, we focus on a few methods which contribute significantly to the accuracy and analysis of PPE-based HRTF data. The dedicated setup allows measuring a full 360 degree map in automated fashion. It includes a special ring setup with 25 speakers, and a precise turn table that is used to adjust the angle of the device under test with respect to the ring. Binaural measurements were performed on a set of common PPE items on a Head And Torso Simulator (HATS) system, including hard hats, safety glasses, hearing protection, and various face masks. An overview of the data is presented.

Characterization of a 3-hydroxyanthranilic acid 6-hydroxylase involved in paulomycin biosynthesis

Paulomycins (PAUs) refer to a group of glycosylated antibiotics with attractive antibacterial activities against Gram-positive bacteria. They contain a special ring A moiety that is prone to dehydrate between C-4 and C-5 to a quinone-type form at acidic condition, which will reduce the antibacterial activities of PAUs significantly. Elucidation of the biosynthetic mechanism of the ring A moiety may facilitate its structure modifications by combinatorial biosynthesis to generate PAU analogues with enhanced bioactivity or stability. Previous studies showed that the ring A moiety is derived from chorismate, which is converted to 3-hydroxyanthranilic acid (3-HAA) by a 2-amino-2-deoxyisochorismate (ADIC) synthase, a 2,3-dihydro-3-hydroxyanthranilic acid (DHHA) synthase, and a DHHA dehydrogenase. Unfortunately, little is known about the conversion process from 3-HAA to the highly decorated ring A moiety of PAUs. In this work, we characterized Pau17 as an unprecedented 3-HAA 6-hydroxylase responsible for the conversion of 3-HAA to 3,6-DHAA by in vivo and in vitro studies, pushing one step forward toward elucidating the biosynthetic mechanism of the ring A moiety of PAUs.

Infrared small target detection via adaptive M-estimator ring top-hat transformation

Top-Hat transformation is an essential technology in the field of infrared small target detection. Many modified Top-Hat transformation methods have been proposed based on the different structure of structural elements. However, these methods are still hard to handle the dim targets and complex background. It can be summarized as two reasons, one is that the structural elements cannot suppress the background adaptively due to the fixed value of structural elements in image. Another is that simple structural element cannot utilize the local feature for target enhancement. To overcome these two limitations, a special ring Top-Hat transformation based on M-estimator and local entropy is proposed in this paper. First, an adaptive ring structural element based on M-estimator is used to suppress the complex background. Second, a novel local entropy is proposed to weight structural element for capturing local feature and target enhancement. Finally, a comparison experiment based on massive infrared image data (more than 500 infrared target images) is done. And the results demonstrate that the proposed algorithm acquires better performance compared with some recent methods.

Aging Estimation of MOS FETs Using Aging‐Tolerant/Aged Ring Oscillators

Transistor aging occurs in nanoscale LSIs and is a factor that degrades large scale integration (LSI) performance. Because aging decreases the switching speed of transistors, LSIs ultimately malfunction due to the increase in the propagation delay. This paper proposes a procedure starting from the estimation of the aging amount at the metal‐oxide‐semiconductor field‐effect transistor (MOS FET) level to that at the gate level. The aging effect at the MOS FET level is extracted from changes in the periods of two special ring oscillators. The aging amount at the MOS FET is estimated by using a calculation model based on an RC circuit. The estimated aging amount is used to estimate the increase in propagation delay due to aging at the gate level. Results of circuit simulations showed that the proposed procedure produced estimations with an error rate of less than 4.6% for the increase in switching delay, and less than 0.6% for the increase in threshold voltage. For estimation of path delay, the range of the error rate was from –22.7 to +11.4%. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

The Lord of the NanoRings: Cyclodextrins and the battle against SARS-CoV-2.

A handful of singular structures and laws can be observed in nature. They are not always evident but, once discovered, it seems obvious how to take advantage of them. In chemistry, the discovery of reproducible patterns stimulates the imagination to develop new functional materials and technological or medical applications. Two clear examples are helical structures at different levels in biological polymers as well as ring and spherical structures of different size and composition. Rings are intuitively observed as holes able to thread elongated structures. A large number of real and fictional stories have rings as inanimate protagonists. The design, development or just discovering of a special ring has often been taken as a symbol of power or success. Several examples are the Piscatory Ring wore by the Pope of the Catholic Church, the NBA Championship ring and the One Ring created by the Dark Lord Sauron in the epic story The Lord of the Rings. In this work, we reveal the power of another extremely powerful kind of rings to fight against the pandemic which is currently affecting the whole world. These rings are as small as ~1nm of diameter and so versatile that they are able to participate in the attack of viruses, and specifically SARS-CoV-2, in a large range of different ways. This includes the encapsulation and transport of specific drugs, as adjuvants to stabilize proteins, vaccines or other molecules involved in the infection, as cholesterol trappers to destabilize the virus envelope, as carriers for RNA therapies, as direct antiviral drugs and even to rescue blood coagulation upon heparin treatment. "One ring to rule them all. One ring to find them. One ring to bring them all and in the darkness bind them." J. R. R. Tolkien.

Heterostructure based demultiplexer using solid–solid phononic crystal ring resonators

This paper presents a novel approach to design a heterostructure demultiplexer using the ring resonators in a solid–solid phononic crystal (PnC). The proposed PnC structure is a square lattice contained circular tungsten cylinders embedded in a polycrystalline silicon background. The heterostructure-based demultiplexer consists of three different sections, where every section includes a bus waveguide and an output waveguide coupled to each other through a special ring resonator. The simulation results show that different frequencies emitted from the heterostructure demultiplexer outputs in the range of GHz. The achieved maximum and minimum transmissions are about 88% and 42%. Furthermore, the very high average quality factor of 4570 results are among output channels. Moreover, the maximum crosstalk (the worst one) among the outputs is −13 dB, which is a desirable value. Finally, the effect of temperature variations on the demultiplexer performance is explored. It is revealed that by enhancing the constituted material temperature the resonance frequencies decrease almost linearly and gradually.

The index of ideality of correlation and the variety of molecular rings as a base to improve model of HIV-1 protease inhibitors activity

Computational prediction of HIV-1 protease inhibitor via quantitative structure–activity relationships (QSARs) is a popular study in the field of computational chemistry. The aim of the present study was building up of QSAR models for anti-HIV activity by means of the CORAL software ( http://www.insilico.eu/coral ). Applying of correlation weights for five and six-member molecular rings as components of the target function in the Monte Carlo optimization that is aimed to build up correlation between activity of HIV-1 protease inhibitors expressed as pIC50 = lg[1/(IC50 × 109)] and optimal descriptor improves the predictive potential. Simplified molecular input-line entry system (SMILES) is used as the representation of the molecular structure of HIV-1 protease inhibitors for the QSAR analysis. New criterion of predictive potential so-called index of ideality of correlation (IIC) has been appllied to improve the model for HIV-1 protease inhibitors activity. High correlation coefficients were observed between the experimental and predicted anti-HIV activity. Applying of special ring code as component of the Monte Carlo calculation significantly improves the statistical quality of the model. Furthermore, applying of the IIC as component of the Monte Carlo optimization improves the predictive potential of the CORAL models. The presence of the rings and the quality of these are very important molecular features which are able to improve statistical quality of model for anti-HIV activity. In addition, the ability of IIC to improve predictive potential of a model has been confirmed.

Analogs of the Lebesgue Measure and Diffusion in a Hilbert Space

We study shift-invariant measures on a real separable Hilbert space E, which are also invariant with respect to orthogonal transforms. In this article a finitely additive analogue of the Lebesgue measure is constructed. It is a non-negative finitely additive shift-invariant measure on a special ring of subsets from a space E, which is invariant with respect to orthogonal transforms. The ring contains all infinite-dimensional rectangles, whose products of side lengths are absolutely convergent. We define a Hilbert space \( \mathcal{\mathscr{H}} \), whose elements are complex-valued functions. The functions are square-integrable by some shift-invariant measure, which is also invariant with respect to rotations. We define the expected values of shift operators over random vectors, whose distribution is given by a family of Gaussian measures on a space E. The measures form a semigroup with respect to convolution. We prove that the expected values form a semigroup of contracting self-adjoint operators on a space \( \mathcal{\mathscr{H}} \). The semigroup is not strongly continuous. We also find invariant subspaces, where the semigroup is continuous in the strong operator topology. We investigate the structure of arbitrary (not necessarily continuous) operator semigroups of contracting self-adjoint transforms on a Hilbert space. We show that the suggested in Orlov et al. (Izv. Math. 80(6), 1131–1158 2016) method of the Feynman averaging is applicable to discontinuous semigroups.

Self-healing mineralization and enhanced anti-corrosive performance of polyurethane CaCO3 composite film via β-CD induction

A novel organic composite coating was successfully fabricated through in situ mineralizing in artificial seawater for a lasting anti-corrosive coating. The mineralized composite films make full use of the advantages including rich hydroxyl group and special ring structure of β-cyclodextrin as well as superior adhesion and high flexibility of waterborne polyurethane coating. The results show the β-CD remarkably promotes the mineralization of CaCO3 on WPU substances through the effective adsorption and complexation of hydrophobic cavity to calcium ions. The dense organic-inorganic composite film exhibits outstanding anti-corrosive performance with corrosion rate of 1.39 × 10−3 mm/year for 3CD-WPU sample, being much less than 7.36 × 10−2 mm/year for WPU coating under same conditions. The excellent anti-corrosion performance is mainly attributed to the uniform nucleation site provided by CD-WPU and further formation of dense CaCO3 film. Furthermore, the radial distribution function and adsorb energy theoretic analysis by molecular dynamic simulation definitely reveal and support the mechanism of β-CD promoting the CaCO3 mineralization.

A minimal ring extension of a large finite local prime ring is probably ramified

Given any minimal ring extension [Formula: see text] of finite fields, several families of examples are constructed of a finite local (commutative unital) ring [Formula: see text] which is not a field, with a (necessarily finite) inert (minimal ring) extension [Formula: see text] (so that [Formula: see text] is a separable [Formula: see text]-algebra), such that [Formula: see text] is not a Galois extension and the residue field of [Formula: see text] (respectively, [Formula: see text]) is [Formula: see text] (respectively, [Formula: see text]). These results refute an assertion of G. Ganske and McDonald stating that if [Formula: see text] are finite local rings such that [Formula: see text] is a separable [Formula: see text]-algebra, then [Formula: see text] is a Galois ring extension. We identify the homological error in the published proof of that assertion. Let [Formula: see text] be a finite special principal ideal ring (SPIR), but not a field, such that [Formula: see text] has index of nilpotency [Formula: see text] ([Formula: see text]). Impose the uniform distribution on the (finite) set of ([Formula: see text]-algebra) isomorphism classes of the minimal ring extensions of [Formula: see text]. If [Formula: see text] (for instance, if [Formula: see text]), the probability that a random isomorphism class consists of ramified extensions of [Formula: see text] is at least [Formula: see text]; if [Formula: see text] (for instance, if [Formula: see text] for some odd prime [Formula: see text]), the corresponding probability is at least [Formula: see text]. Additional applications, examples and historical remarks are given.

On Special Fiber Rings of Modules

AbstractWe prove results concerning the multiplicity as well as the Cohen–Macaulay and Gorenstein properties of the special fiber ring $\mathscr{F}(E)$ of a finitely generated $R$-module $E\subsetneq R^{e}$ over a Noetherian local ring $R$ with infinite residue field. Assuming that $R$ is Cohen–Macaulay of dimension 1 and that $E$ has finite colength in $R^{e}$, our main result establishes an asymptotic length formula for the multiplicity of $\mathscr{F}(E)$, which, in addition to being of independent interest, allows us to derive a Cohen–Macaulayness criterion and to detect a curious relation to the Buchsbaum–Rim multiplicity of $E$ in this setting. Further, we provide a Gorensteinness characterization for $\mathscr{F}(E)$ in the more general situation where $R$ is Cohen–Macaulay of arbitrary dimension and $E$ is not necessarily of finite colength, and we notice a constraint in terms of the second analytic deviation of the module $E$ if its reduction number is at least three.