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health risk of whole body vibration in mining trucks during various operational conditions

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journal of Central South University 2017年第8期24卷 1808-1816页

作者： Rahimdel m.j mirzaei m Sattarvand j hoseinie S.h Department of mining Engineering Sahand University of TechnologyTabriz ***Iran Department of mechanical Engineering Sahand University of TechnologyTabriz ***Iran Department of mining Engineering Isfahan University of TechnologyIsfahan ***Iran

mining machineries are generally exposed to intensive vibrations in harsh mining environment. If vibrations are beyond the tolerable limit, the machine and its operator health will be under the risk. In this work, the vibration of a mining truck at different operational conditions are simulated and discussed. To achieve this aim, three haul roads with low, medium and poor qualities are considered based on the ISO standard. Accordingly, the vibration of a mining truck in different speeds, payload and distribution qualities of materials in the dump body are evaluated in each haul road quality using Trucksim software. The simulation results with statistical discussions indicate that the truck speed and the materials distribution quality have significant effects on the root mean square(RmS) of vertical vibrations. however, the effect of the payload is not considerable on the RmS. moreover, the accumulation of materials on the rear side of the truck dump body is efficient on the vibrational health risk.

关键词： mining trucks operational conditions health risk whole body vibration

Comparisons of the suture zones along a geotraverse from the Scythian Platform to the Arabian Platform

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Geoscience Frontiers 2014年第6期5卷 855-875页

作者： ali Yilmaz Shota Adamia hüseyin Yilmaz Cumhuriyet University Engineering FacultyDepartment of Environmental EngineeringKayseri StreetCU.CampusTR-58140 SivasTurkey Nodia Institute of Geophysics 1M.Alexidze Str.0195TbilisiGeorgia Cumhuriyet University Engineering FacultyDepartment of Geophysical EngineeringTR-58140 SivasTurkey

The area from the Greater Caucasus to the southeast Turkey is characteri：;.ed and shaped by several major continental blocks. These are Scythian Platform, Pontian-Transcaucasu.,; Continent-Arc System （PTCAS）, the Anatolian-lranian and the Arabian Platforms. The aim of this paper is to define these continental blocks and describe and also compare their boundary relationships along the suture zones. The Scythian Platform displays the evidence of the hercynian and Alpine orogens. This platform is separated from the PTCAS by the Greater Caucasus Suture Zone. The incipient collision began along this suture zone before middle-late Carboniferous whereas the final collision occurred before Oligocene. The PTCAS can be divided into four structural units：（1） the Georgian Block - northern part of the Pontian-Transcaucasian island-arc, （2） the southern and eastern Black Sea Coast-Adjara-Trialeti Unit, （3） the Artvin-Bolnisi Unit, comprising the northern part of the southern Transcaucasus, and （4） the Imbricated Bayburt-Garabagh Unit. The PTCAS could be separated from the Anatolian Iranian Platform by the North Anatolian-Lesser Caucasus Suture （NALCS） zone. The initial collision was developed in this suture zone during Senonian-early Eocene and final collision before middle Eocene or Oligocene-miocene. The Anatolian-lranian Platform （AIP） is made up of the Tauride Platform and its metamorphic equivalents together with Iranian Platform. It could be separated from the Arabian Platform by the Southeastern Anatolian Suture （SEAS） zone. The collision ended before late miocene along this suture zone. The southernmost continental block of the geotraverse is the Arabian Platform, which constitutes the northern part of the Arabian-African Plate. This platform includes a sequence from the Precambrian felsic volcanic and clastic rocks to the Campanian-early maastrichtian fiyschoidal clastics. All the suture zones include mORB and SSZ-types ophiolites in different ages. however, the ages of

关键词： Scythian Plattorm Arabian Platform Suture zones Ceotraverse

Formation and Characterization of Ceramic Nanocomposite Crystalline Coatings on Aluminium by Anodization

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journal of materials Science & Technology 2013年第7期29卷 595-602页

作者： m.mubarak ali V.Raj School of Chemical Engineering Yeungnam UniversityGyeongsanGyeongbuk 712-749South Korea Advanced materials Research Laboratory Department of ChemistryPeriyar UniversitySalem 636 011Tamil NaduIndia

Ceramic nanocomposite coatings have been synthesized on aluminium by using lithium sulphate electrolyte with zirconium silicate additive by anodization. The effects of current density （CD） on microhardness, structure, composition and surface topography of the oxide layer formed at various CDs （0.1-0.25 A/cm^2） have been studied. Crystalline coatings formed at 0.25 A/cm^2 have been （width 95 nm） observed with a relatively uniform distribution confirmed by scanning electron microscopy. Additionally, the average microhardness value of ceramic nanocomposite coatings fabricated from lithium sulphate-zirconium silicate bath is approximately 8.5 times higher than that of the as-received aluminium. The surface statistics of the coatings is discussed in detail to explain the roughness and related parameters for better understanding. These observations demonstrate the importance of surface statistics in controlling the morphology of the coatings and its properties. From the X-ray diffraction investigations, it can be concluded that the formed nanocomposite coatings are crystalline in nature and that the crystallinity of the coatings decreases with increasing applied current density.

关键词： Anodization Nanocomposite Coatings Alumina Aluminium

Augmented Lyapunov approach to h_∞ state estimation of static neural networks with discrete and distributed time-varying delays

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Chinese Physics B 2015年第5期24卷 140-147页

作者： m.Syed ali R.Saravanakumar Department of mathematics Thiruvalluvar University

This paper deals with h∞ state estimation problem of neural networks with discrete and distributed time-varying delays. A novel delay-dependent concept of h∞ state estimation is proposed to estimate the h∞ performance and global asymptotic stability of the concerned neural networks. By constructing the Lyapunov-Krasovskii functional and using the linear matrix inequality technique, sufficient conditions for delay-dependent h∞ performances are obtained, which can be easily solved by some standard numerical algorithms. Finally, numerical examples are given to illustrate the usefulness and effectiveness of the proposed theoretical results.

关键词： distributed delay h∞ state estimation neural networks stability analysis

Reaction kinetic model for a recent co-produced water treatment technology

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journal of Environmental Sciences 2011年第3期23卷 360-365页

作者： Abdulwahab m ali Tuwati mark A.Bentley Chemical & Petroleum Engineering University of Wyoming

With the increasing demand for fossil based energy and implementation of progressively strict environmental pollution control standards, treatment of a large amount of co-produced waters （CPWs） from fossil based energy production has become increasingly important. Removal of bicarbonate with h2SO4 has been recently studied as a simple and cost-effective method to decrease the alkalinity of CPWs. The present work investigates the kinetics of the reaction between h2SO4 and NahCO3, which could provide the base for scaling-up the CPW treatment technology. Based on the measured quantity change of the CO2 gas generated from the reaction between h2SO4 and NahCO3 with time under specified initial reaction conditions, the reaction orders with respect to h2SO4 and NahCO3 were determined. Experiments were also conducted within the temperature of 15-30℃ to find various global rate coefficients of the reaction to calculate the activation energy and the pre-exponential factor of the empirical Arrhenius form of the bicarbonate removal reaction, which are 197.7 kj/mol and 3.13 × 1034 （mol-3.7 ×L3.7 ×sec^-1 ）, respectively.

关键词： fossil fuels water wastewater alkalinity bicarbonate

Improved delay-dependent robust h_∞ control of an uncertain stochastic system with interval time-varying and distributed delays

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Chinese Physics B 2014年第12期23卷 5-13页

作者： m.Syed ali R.Saravanakumar Department of mathematics Thiruvalluvar University

In this paper, the robust h∞control problem for a class of stochastic systems with interval time-varying and distributed delays is discussed. The system under study involves parameter uncertainty, stochastic disturbance, interval time-varying,and distributed delay. The aim is to design a delay-dependent robust h∞control which ensures the robust asymptotic stability of the given system and to express it in the form of linear matrix inequalities（LmIs）. Numerical examples are given to demonstrate the effectiveness of the proposed method. The results are also compared with the existing results to show its conservativeness.

关键词： distributed delay interval time-varying delay h∞control linear matrix inequality(LmI) stochastic systems

Comparative Study of Valency-Based Topological Descriptor for hexagon Star Network

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Computer Systems Science & Engineering 2021年第2期36卷 293-306页

作者： ali N.A.Koam ali Ahmad m.F.Nadeem Department of mathematics College of ScienceJazan UniversityNew CampusJazan2097Saudi Arabia College of Computer Science&Information Technology jazan University JazanSaudi Arabia Department of mathematics COMSATS University IslamabadLahore CampusLahore54000Pakistan

A class of graph invariants referred to today as topological indices are inefficient progressively acknowledged by scientific experts and others to be integral assets in the depiction of structural *** structure of an interconnection network can be represented by a *** the network,vertices represent the processor nodes and edges represent the links between the processor *** invariants play a vital feature in graph theory and distinguish the structural properties of graphs and networks.A topological descriptor is a numerical total related to a structure that portray the topology of structure and is invariant under structure *** are various uses of graph theory in the field of basic *** main notable utilization of a topological descriptor in science was by Wiener in the investigation of paraffin breaking *** this paper we study the topological descriptor of a newly design hexagon star *** preciously,we have computed variation of the Randic0 R0,fourth Zagreb m4,fifth Zagreb m5,geometric-arithmetic GA;atom-bond connectivity ABC;harmonic h;symmetric division degree SDD;first redefined Zagreb,second redefined Zagreb,third redefined Zagreb,augmented Zagreb AZI,Albertson A;Irregularity measures,Reformulated Zagreb,and forgotten topological descriptors for hexagon star *** the analysis of the quantitative structure property relationships(QSPRs)and the quantitative structure activity relationships(QSARs),graph invariants are important tools to approximate and predicate the properties of the biological and chemical *** also gave the numerical and graphical representations comparisons of our different results.

关键词： Topological indices degree-based index hexagon star network

Robust h_∞ control of uncertain systems with two additive time-varying delays

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Chinese Physics B 2015年第9期24卷 25-34页

作者： m.Syed ali R.Saravanakumar Department of mathematics Thiruvalluvar University

This paper is concerned with the problem of delay-dependent robust h∞control for a class of uncertain systems with two additive time-varying delays. A new suitable Lyapunov–Krasovskii functional（LKF） with triple integral terms is constructed and a tighter upper bound of the derivative of the LKF is derived. By applying a convex optimization technique, new delay-dependent robust h∞stability criteria are derived in terms of linear matrix inequalities（LmI）. Based on the stability criteria, a state feedback controller is designed such that the closed-loop system is asymptotically ***, numerical examples are given to illustrate the effectiveness of the proposed method. Comparison results show that our results are less conservative than the existing methods.

关键词： additive time-varying delays Lyapunov method h∞ control linear matrix inequality

hydration Characteristics and Immobilization of Cr(Ⅵ) in Slag Cement-CKD Pastes under hydrothermal Treatment

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journal of Wuhan University of Technology(materials Science) 2015年第5期30卷 1013-1019页

作者： m R Shatat Gomaa A m ali m A Tantawy Chemistry Department Faculty of Science Al-Azhar University Faculty of Industrial Science and Technology University Malaysia Pahang (UMP) Chemistry Department Faculty of Science Minia University

The effect of hydrothermal curing regimes on the hydration characteristics of slag cement containing different ratios of cement kiln dust has been studied. The samples for this study were combination of slag cement and cement kiln dust(5%-25%) without and with immobilization of 5% Cr(VI) by mass. Pastes were hydrothermally treated at 180 ℃ for different periods(2-24 h) in well closed stainless steel capsule. The hydration characteristics of these pastes were studied by measuring the compressive strength, bulk density, total porosity and combined water content. The findings were further supported by XRD and SEm analysis. The results indicated that the hydration characteristics of slag cement paste containing cement kiln dust 10% by mass were enhanced, especially at later ages(24 h) of hydration. That is due to the hydrothermal curing regimes of immobilized pastes accelerating hydration reactions and precipitation of Ca Cr O4, indicating that Cr(VI) can be solidified in the cement paste. This precipitation leads to pore formation in hydrated slag cement pastes.

关键词： hydrothermal immobilization slag cement CKD pastes