Robust normalization and guaranteed cost control for a class of uncertain singular Markovian jump systems via hybrid impulsive control

This paper investigates the problem of robust normalization and guaranteed cost control for a class of uncertain singular Markovian jump systems. The uncertainties exhibit in both system matrices and transition rate matrix of the Markovian chain. A new impulsive and proportional-derivative control strategy is presented, where the derivative gain is to make the closed-loop system of the singular plant to be a normal one, and the impulsive control part is to make the value of the Lyapunov function does not increase at each time instant of the Markovian switching. A linearization approach via congruence transformations is proposed to solve the controller design problem. The cost function is minimized via solving an optimization problem under the designed control scheme. Finally, three examples (two numerical examples and an RC pulse divider circuit example) are provided to illustrate the effectiveness and applicability of the proposed methods

Nano-mineralogy and growth environment of Fe-Mn polymetallic crusts and nodules from the South China Sea

Fe-Mn polymetallic crusts and nodules from the South China Sea (SCS) consist of submarine ferromanganese (Fe-Mn) oxide precipitates, and represent important marine mineral resource with substantial economic and scientific research value. Previous studies on the SCS polymetallic crusts and nodules were mainly focused on their bulk mineralogy and geochemistry, whilst research on their nanomineralogy is still lacking. In this study, transmission electron microscopy (TEM), Raman spectroscopic mapping, and in-situ micro X-ray diffraction (XRD) analysis were conducted on the nano-mineralogy of the SCS polymetallic crusts and nodules. It is found that the SCS polymetallic crusts and nodules consist mainly of layered/columnar/mottled nano-phase Fe-Mn minerals and detritus such as quartz, feldspar, and clays. Also, an independent Ti mineral phase has been documented, and the mineralogical analysis reveals the transformation from vernadite to birnessite and todorokite. Titanium forms colloidal minerals in seawater and precipitates into the crusts and nodules with other colloids, such as FeOOH and Si-Al. Vernadite and birnessite can be transformed to todorokite with stable structure under sub-oxic conditions. Therefore, the SCS polymetallic crusts and nodules were formed in a short period of sub-oxic environment and diagenetic process, and the transformation can influence the enrichment of Ni and other metals during the crust/nodule growth

6,6′-Dihydr­oxy-2,2′-[(pentane-1,5-diyl­dioxy)bis­(nitrilo­methyl­idyne)]diphenol

The mol­ecule of the title compound, C19H22N2O6, assumes a W-shaped configuration with the dihedral angle between the two halves of the mol­ecule being 82.48 (5)°. There is one half-mol­ecule in the asymmetric unit with a crystallographic twofold rotation axis passing through the central C atom of the five methylene groups in the [—CH=N—O—(CH2)5—O—N=CH—] bridge. The dihedral angle formed by the two benzene rings in each mol­ecule of the title compound is 84.18 (4)°. There are strong intra­molecular O—H⋯N and O—H⋯O hydrogen bonds and weak inter­molecular π–π stacking inter­actions between neighbouring benzene rings, and the inter­molecular plane-to-plane distances are 3.488 (2) and 3.841 (3) Å along the b and c axes, respectively. In the crystal structure, inter­molecular O—H⋯O hydrogen bonds link each mol­ecule to two others, forming an infinite three-dimensional supra­molecular structure

Efficient Quantum Circuit Cutting by Neglecting Basis Elements

Quantum circuit cutting has been proposed to help execute large quantum circuits using only small and noisy machines. Intuitively, cutting a qubit wire can be thought of as classically passing information of a quantum state along each element in a basis set. As the number of cuts increase, the number of quantum degrees of freedom needed to be passed through scales exponentially. We propose a simple reduction scheme to lower the classical and quantum resources required to perform a cut. Particularly, we recognize that for some cuts, certain basis element might pass "no information" through the qubit wire and can effectively be neglected. We empirically demonstrate our method on circuit simulators as well as IBM quantum hardware, and we observed up to 33 percent reduction in wall time without loss of accuracy.Comment: 7 pages, 5 figures, submitted to 37th IEEE International Parallel & Distributed Processing Symposiu

catena-Poly[[dichloridozinc(II)]-μ-1,1′-(butane-1,4-di­yl)diimidazole-κ2 N 3:N 3′]

The title compound, [ZnCl2(C10H14N4)]n, is a coordination polymer consisting of zigzag chains propagating in [001], in which the metal cation exhibits a distorted tetrahedral ZnCl2N2 coordination. Adjacent chains are linked by inter­molecular C—H⋯Cl hydrogen bonds, forming a three-dimensional supra­molecular network

Reduction of human mobility matters during early covid-19 outbreaks: Evidence from india, japan and china

Mobility restrictions have been a heated topic during the global pandemic of coronavirus disease 2019 (COVID-19). However, multiple recent findings have verified its importance in blocking virus spread. Evidence on the association between mobility, cases imported from abroad and local medical resource supplies is limited. To reveal the association, this study quantified the importance of inter-and intra-country mobility in containing virus spread and avoiding hospitalizations during early stages of COVID-19 outbreaks in India, Japan, and China. We calculated the timevarying reproductive number (Rt) and duration from illness onset to diagnosis confirmation (Doc), to represent conditions of virus spread and hospital bed shortages, respectively. Results showed that inter-country mobility fluctuation could explain 80%, 35%, and 12% of the variance in imported cases and could prevent 20 million, 5 million, and 40 million imported cases in India, Japan and China, respectively. The critical time for screening and monitoring of imported cases is 2 weeks at minimum and 4 weeks at maximum, according to the time when the Pearson’s Rs between Rt and imported cases reaches a peak (>0.8). We also found that if local transmission is initiated, a 1% increase in intra-country mobility would result in 1430 (±501), 109 (±181), and 10 (±1) additional bed shortages, as estimated using the Doc in India, Japan, and China, respectively. Our findings provide vital reference for governments to tailor their pre-vaccination policies regarding mobility, especially during future epidemic waves of COVID-19 or similar severe epidemic outbreaks