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stochastic Models to Mitigate sparse sensor Attacks in Continuous-Time Non-Linear Cyber-Physical systems

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Computers, Materials & Continua 2023年第9期76卷 3189-3218页

作者： Borja Bordel sánchez Ramón Alcarria Tomás Robles Information Technologies Department Universidad Politécnica de MadridMadrid28031Spain Geospatial Information Department Universidad Politécnica de MadridMadrid28031Spain

Cyber-Physical systems are very vulnerable to sparse sensor *** current protection mechanisms employ linear and deterministic models which cannot detect attacks ***,in this paper,we propose a new non-linear generalized model to describe Cyber-Physical *** model includes unknown multivariable discrete and continuous-time functions and different multiplicative noises to represent the evolution of physical processes and randomeffects in the physical and ***,the digitalization stage in hardware devices is represented *** and most critical sparse sensor attacks are described through a stochastic *** reconstruction and protectionmechanisms are based on aweighted *** probability in data samples is estimated through different indicators commonly employed in non-linear dynamics(such as the Fourier transform,first-return maps,or the probability density function).A decision algorithm calculates the final reconstructed value considering the previous error *** experimental validation based on simulation tools and real deployments is also carried ***,the new technology performance and scalability are *** prove that the proposed solution protects Cyber-Physical systems against up to 92%of attacks and perturbations,with a computational delay below 2.5 *** proposed model shows a linear complexity,as recursive or iterative structures are not employed,just algebraic and probabilistic *** conclusion,the new model and reconstructionmechanism can protect successfully Cyber-Physical systems against sparse sensor attacks,even in dense or pervasive deployments and scenarios.

关键词： Cyber-physical systems sparse sensor attack non-linear models stochastic models security

Epidemiology of Fetal Death and Analysis of Causes According to CODAC Classification at Amath Dansokho Regional hospital of Kedougou, senegal

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Open Journal of Obstetrics and Gynecology 2023年第12期13卷 1909-1918页

作者： Mouhamadou Wade Mamour Gueye Abdoul aziz Diouf Mouhamet sene Khadim Faye Adjie Betty Faye heyssam Ghais Amath Dansokho Regional hospital of Kedougou Kedougou Senegal Gynecology and Obstetrics Department Cheikh Anta DIOP University Dakar Senegal

Objectives: This paper aims to study the epidemiology and causes of fetal deaths in utero at Regional hospital Amath Dansokho of Kedougou (RhADK). Methodology: This was a retrospective epidemiological study conducted at the Maternity Ward of the Regional hospital Amath Dansokho of Kedougou from June 01, 2022 to June 30, 2023, including all patients seen for delivery care. Data were analyzed using statistical Package for social science (sPss 22, Windows version). The parameters studied were the frequency of in-utero fetal death, sociodemographic characteristics, pregnancy and delivery data, neonatal data and cause-of-death classification according to the Cause of Death and Associated Conditions (CODAC) classification. Results: We recorded 1628 deliveries, with 231 cases of in-utero fetal death, a frequency of 14.2%. Fetal death occurred most frequently in multiparous women (64.5%). The majority of patients (72.3%) were transferred. 51.9% of patients with fetal death had at least 3 antenatal visits. On admission, fetal heart rate was absent in 73.2% of patients. The etiology of in-utero fetal death was dominated by maternal factors (high blood pressure, anaemia and diabetes), which accounted for 36.9% of deaths, followed by placental pathologies (retroplacental haematoma) and intrapartum pathologies (uterine rupture, abnormal presentation). Conclusion: In-utero fetal death can be prevented, and is mainly due to direct obstetric complications. The focus should be on the prevention and management of hypertensive disorders and their complications during pregnancy, the fight against anaemia and, above all, the rapid and correct management of dystocia.

关键词： Obstetrical Complications Fetal Death CODAC Classification

Effect of adrenalectomy and hydrocortisone on ventral prostate of rats

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Asian Journal of Andrology 2001年第4期3卷 289-300页

作者： Neena Nair R.s.Bedwal R.s.Mathur Cell Biology Laboratory Department of Zoology University of Rajasthan Jaipur 302004 IndiaCell Biology Laboratory Department of Zoology University of Rajasthan Jaipur 302004 IndiaCell Biology Laboratory Department of Zoology University of Rajasthan Jaipur 302004 India

Aim: To study the effects of adrenalectomy and hydrocortisone on the ventral prostate of sD rats. Methods: Inadrenalectomised (ADX) and ADX + hydrocortisone (1, 2, or 4 mg) treated rats, the prostatic histology and thecholesterol, protein, zinc, and copper levels and the enzymic profile (acid phosphatase, alkaline phosphatase, aryl sul-phatase, lactic dehydrogenase, and leucine aminopeptidase) in the prostatic tissue were determined; the serum hormon-al profile (testosterone, Fsh and Lh) was also assayed. Results; Adrenalectomy caused a progressive degenerationin prostatic structure that was not reversed by hydrocortisone treatment. The serum testosterone were significantly lowerin ADX than in sham operated rats and lower in ADX + hydrocortisone than in ADX-C rats (P he serumFsh and Lh were below the detection limit of 1 mIU/mL. The enzymatic activity was higher in ADX than in sham op-erated rats and higher in ADX + hydrocortisone than in ADX-C rats (Phe prostatic zinc levels weresignificantly higher in sham operated than in ADX, and higher in ADX-C than in ADX + hydrocortisone rats (P he prostatic copper level was significantly lower in sham operated than in ADX, and lower in ADX-C thanin the ADX + hydrocortisone rats (P sion; In rats, adrenalectomy leads to pathological and func-tional changes of the prostate. hydrocortisone treatment at the doses employed did not reverse these changes. (Asian JAndrol 2001 Dec; 3: 289 - 300)

关键词： adrenalectomy ventral prostate hydrocortisone testosterone Fsh Lh cholesterol zinc copper acid phosphatase alkaline phosphatase aryl sulphatase lactic dehydrogenase leucine aminopeptidase

spectroscopic investigations and luminescence spectra of sm3+ doped soda lime silicate glasses

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Journal of Rare Earths 2009年第5期27卷 773-780页

作者： Y.K. sharma s.s.L. surana R.K. singh Department of Physics Govt. Post Graduate College Rudrapur 263153 (U S Nagar) India Department of Physics J. N. V. University Jodhpur-342001 India Department of Physics Govt. Post Graduate College Rudrapur 263153 (U S Nagar) India

sm3+ doped soda lime silicate glasses co-doped with As2O3 were prepared and characterised by measuring their absorption spectra in UV-VIs/NIR regions and luminescence spectra in the visible region. Judd-Ofelt intensity parameters, Ωλ, were evaluated from the measured intensities of the various absorption bands. Ωλ parameters of these glasses were compared with the Ωλ parameters of other reported sm3+ glasses to study the bonding environment surrounding the sm3+ in the present glasses. Presence of [AsO4]3– tetrahedra in the second coordination sphere around the central sm3+ ion made these glasses less covalent as compared to other oxide glasses but the ratio Ω4/Ω6 of the 1.83 indicated them to be fairly stable. With the help of Ωλ parameters and luminescence data for various emission lines, radiative properties for different emission lines were calculated. The values of radiative properties indicated that 4G5/2→6h7/2 and 4G5/2→6h9/2 transitions responsible for orange luminescence might be used in the development of materials for LED's and other optical devices in the visible region.

关键词： rare earth glasses Judd-Ofelt theory absorption spectroscopy luminescence

Development of CeO_2 nanorods reinforced electrodeposited nickel nanocomposite coating and its tribological and corrosion resistance properties

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Journal of Rare Earths 2018年第12期36卷 1319-1325页

作者： s.shanmugasamy K.Balakrishnan A.subasri s.Ramalingam A.subramania Centre for Nanoscience and Technology Pondicherry University Department of Chemistry Kalasalingam University

A simple electrodeposition technique was used to prepare Ni-CeOnanorods composite coating(Ni-CeONRs) using Watt’s nickel plating bath containing CeOnanorods(NRs) as the reinforcement phase under optimized process conditions. The X-ray diffraction analysis(XRD) was used for the structural analysis of Ni-CeONRs composite coatings and their average crystalline size is ～22 nm for pure Ni and ～18 nm,respectively. The crystalline structure is fcc for the Ni-CeOnanocomposite coatings. The surface morphology of the electrodeposited Ni-CeONRs composite coatings was analyzed by scanning electron microscopy(sEM). Microhardness of pure Ni and Ni-CeONRs composite coatings are found to be 253 hV and 824 hV, respectively. The inclusion of CeONRs increases the microhardness of Ni-CeONRs composite coatings. The corrosion resistance behavior of Ni-CeONRs composite coating was evaluated by Tafel polarization and AC impedance methods. It is revealed that CeONRs reinforced Ni matrix shows higher microhardness and corrosion resistance than existing reported electrodeposited pure Ni and CeOnanoparticles reinforced Ni coatings.

关键词： CeO_2 nanorods Rare earths Electrodeposition Nanocomposite coating Microhardness

Nonlinear optimal control of rotating flexible shaft in active magnetic bearings

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science China(Technological sciences) 2011年第5期54卷 1084-1094页

作者： G. s. TOMBUL s. P. BANKs Department of Automatic Control & systems Engineering The University of Sheffield

The optimal control of nonlinear systems has been studied for years by many researchers. however, the application of optimal control problem to nonlinear non-affine systems needs more attention. In this paper we propose an optimal control design technique for a class of nonlinear and control non-affine equations. The dynamic equations of a flexible shaft supported by a pair of active magnetic bearings (AMBs) are used as the nonlinear control non-affine equations. Mathematical model for the flexible beam is chosen to be the well known Timoshenko beam model, which takes rotary inertia and shear deformations into account, and it is assumed that the shaft is supported by two frictionless bearings at the ends. The effective control of such systems is extremely important for very high angular velocity shafts which are a feature of many modern machines. The control must be able to cope with unbalanced masses and hence be very robust. We shall approach the problem by discretising the Timoshenko beam model and using standard difference formulae to develop a finite-dimensional model of the system. Then we use a recently developed technique for controlling nonlinear systems by reducing the problem to a sequence of linear time-varying (LTV) systems. An optimal control designed for each approximating linear, time-varying system and recent results show that this method will converge uniformly on compact time intervals to the optimal solution.

关键词： approximation technique nonlinear optimal control timoshenko beam active magnetic bearings

Discovery of the chitinozoans Belonechitina capitata from the shiala Formation of northeastern Garhwal-Kumaon Tethys himalaya,Pithoragarh District, Uttrakhand, India

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Geoscience Frontiers 2016年第5期7卷 859-864页

作者： h.N.sinha Jacques Verniers Department of Geology Vinoba Bhave University Hazaribag 825301 India Research Unit Palaeontology Department of Geology and Soil Science WE13 Ghent University Belgium

Belonechitina capitata, a typically middle to late Ordovician chitinozoan index taxon was for the first time recovered from the northeastern Kumaon region, a part of Garhwal-Kumaon Tethys basin of the himalaya, India. This species is of great biostratigraphic importance and has already been reported from Avalonia, Baltica and northern Gondwana. The study area was during Ordovician, part of a lowpalaeolatitudinal Gondwana region. The vesicles of recovered forms are black and fragmentary. This is principally attributed to intense tectonic activity during the himalayan orogenic movement which resulted into high thermal alteration. The chitinozoans are found along with melanosclerites.

关键词： Chitinozoan(Belonechitina capitata) Ordovician Northeastern Kumaon Tethys himalaya Low palaeolatitudinal Gondwana shiala Formation

Mineralogy,M-type tetrad effect and radioactivity of altered granites at the *** Garadi shear zone,central Eastern Desert,Egypt

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Chinese Journal Of Geochemistry 2011年第2期30卷 153-164页

作者： El Nahas h.A. El Feky M.G. Mira h. Nuclear Materials Authority P.O. Box 530 Cairo Egypt

The G. Abu Garadi area is covered mainly by metasediments, alkali feldspar granites and stream sediments. The alkali feldspar granite is traversed by a major strike-slip fault trending in an N-s direction as well as two subordinate sets of faults trending NW to WNW for the first one and NE for the second one. These faults represent the shear zones affected by magmatic (syngenetic) as well as hydrothermal (epigenetic) activities causing alteration of the granitic rocks. The most common alteration features are albitization, greisenization and koalinitization. The mass balance calculations of the studied altered samples show enrichments in Zr, Y, Ni, U, Th and Ga and depletions in Zn, sr, Nb, Ba, Pb, Cu and V. Only the greisenized samples exhibit a significant enrichment in Nb, ∑REE budget and pronounced lanthanide tetrad effect (M-type), especially TE1,4, while weakly expressed tetrad effects are for the other albitized and koalinitized samples. Mineralogically, the common accessory minerals in the altered samples include samarskite-(Y), betafite, uranothorite, zircon, fluorite and cassiterite. The greisenized granites contain high eU and eTh than the other altered types, where they are characterized by an assemblage of the radioactive minerals; samarskite-(Y), betafite, uranothorite in addition to zircon. The inter-element relationships between U and Th and also their ratios illustrate that the radioelement distribution in these granites is mainly governed by magmatic processes, in addition to post-magmatic ones. The distribution of chemical elements and the fractionation of some isovalents within the shear zone are largely controlled by the newly formed mineral phases. With respect to uranium mobilization, uranium migrated from the host alkali feldspar granites of G. Abu Garadi, while the shear zones acted as traps for the migrated uranium. Moreover, U migrated in the shear zone during greisenization and albitization, and migrated out during koalinitization.

关键词： M 类型四个效果改变的花岗石 G。Abu Garadi 砍地区中央东方沙漠埃及

Polymer optimization for the development of low-cost moisture sensor based on nanoporous alumina thin film

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Journal of Advanced Ceramics 2013年第4期2卷 341-346页

作者： Manju PANDEY Prabhash MIshRA Debdulal sAhA s.s.IsLAM Nano-sensor Research Laboratory F/O Engineering and TechnologyJamia Millia Islamia(Central University)New DelhiIndia sensors and Actuators Division Central Glass&Ceramic Research Institute196 Raja S.C.Mullick RoadKolkata 700032India

sol-gel processed alumina(Al_(2)O_(3))thin film has been investigated for sensing *** sensor was based on ordered nanoporous Al_(2)O_(3)thin film,which consisted of gold electrodes on both sides of the film forming parallel plate *** substrate was used for supporting thin film moisture *** was achieved by controlling the surface energy of the substrate and polymer(polyvinyl alcohol(PVA))optimization was done for developing rigid thin film over it.A high change in capacitance was observed as the moisture level increased from 5 ppmV to 500 *** electron microscopy(sEM)results revealed that pores were distributed uniformly throughout the sample,which enhanced the adsorption of water molecule over the film.X-ray diffraction(XRD)study clearly confirmed the gamma(γ)phase of alumina thin *** was found that the sensitivity of our sensor was suitable for commercial application.

关键词： sol-gel dip-coating polyvinyl alcohol(PVA) nanoporous hydrophilicity moisture sensor