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High resolution sequence stratigraphy of the Mishrif Formation(Cenomanian-Early Turonian)at zubair oilfield(al-rafdhiah dome),southern Iraq

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Petroleum Research 2024年第1期9卷 61-71页

作者： Aymen A.Lazim maher J.Ismail maher M.Mahdi Geoscience Department Zubair Field Operation DivisionBasra Oil CompanyIraq Basrah Oil Company WQ1 FODBasrahIraq University of Basrah College of ScienceGeology Dept.BasrahIraq

The Mishrif Formation(Cenomanian-E Turonian)is one of the most important geological formations in the Middle East and Iraq because it contains enormous petroleum *** is considered to be the first reservoir in the region,and is still being studied because of its economic *** carbonate of the Mishrif Formation derives from a variety of depositional settings,including mid-ramp,shoal,lagoon,and *** five main microfacies discussed in this paper are w.ckestone,packstone,grainstone,floatstone,and *** most frequent fossilised components found in the Mishrif Formation are rudists,benthic foraminifera,echinoderms,burrow. molluscs,and *** to the microfacies and analysed w.reline log data,the sequence stratigraphy of the studied formation is composed of tw. regression *** parasequences of transgressive-regressive cycles make up the depositional sequence of the Mishrif *** standard depositional environments seem to demonstrate a gradual regression,beginning w.th a short period of the outer ramp,then a steady period of the mid-ramp,and ending in the intertidal ***,the study recorded tw. regional maximum flooding surfaces:K-135 and *** former is present in the low.rmost part of the formation,w.ile the other lies in the *** study show. a close relationship betw.en facies(environments)and hydrocarbon *** increased accumulation focuses on the low.r part of the studied formation,and seems to be low.r in the upper part of the formation as a result of changes in the environment of deposition.

关键词： Mishrif formation Cenomanian Sequence stratigraphy Zubair oilfield Iraq

COMPARING Tw. CLUSTERING-BASED TECHNIQUES TO TRACK MOBILE NODES IN INDUSTRIAL w.RELESS SENSOR NETw.RKS

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Journal of Systems Science and Systems Engineering 2016年第2期25卷 177-209页

作者： Mohammad Gholami Robert w. Brennan Department of Mechanical and Manufacturing Engineering Schulich School of Engineering University of Calgary Calgary Alberta Canada T2N 1N4

Tracking mobile nodes in dynamic and noisy conditions of industrial environments has provided a paradigm for many issues inherent in the area of distributed control systems in general and w.reless sensor netw.rks in particular. Due to the dynamic nature of the industrial environments, a practical tracking system is required that is adaptable to the changes in the environment. More specifically, given the limited resources of w.reless nodes and the challenges created by harsh industrial environments there is a need for a technique that can modify the configuration of the system on the fly as new.w.reless nodes are added to the netw.rk and obsolete ones are removed. To address these issues, tw. cluster-based tracking systems, one static and the other dynamic, are proposed to organize the overall netw.rk field into a set of tracking zones, each composed of a sink node and a set of corresponding anchor nodes. To manage the w.reless nodes activities and inter and intra cluster communications, an agent-based technique is employed. To compare the architectures, w. report on a set of experiments performed in JADE （Java Agent Development Environment）. In these experiments, w. compare tw. agent-based approaches （dynamic and static） for managing clusters of w.reless sensor nodes in a distributed tracking system. The experimental results corroborate the efficiency of the static clusters versus the robustness and effectiveness of the dynamic clusters.

关键词： w.reless sensor netw.rks tracking mobile nodes factory automation distributed adaptive systems reconfigurability

PREDICTION OF CHARACTERISTICS FOR VERTICAL ROUND NEGATIVE BUOYANT JETS IN HOMOGENEOUS AMBIENT

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Journal of Hydrodynamics 2001年第1期13卷 103-110页

作者： Huai, w.X. Li, w. Dep. of River Eng. Coll. of Water Resource Eng. Wuhan 430072 China

The k-Ε turbulence model is used to establish a mathematical model of a vertical round jet w.th negative buoyancy in a static homogeneous ambient. The hybrid finite analytic method, w.th a non-uniform staggered grid, is used to calculate the w.ole flow.field. The variations of centerline velocity, density and turbulent kinetic energy along the axial line for a given exit densimetric Froude number are found to converge to single curves under the unified scaling law.derived by Chen and Rodi. The profiles of mean velocities, mean density difference and the half-w.dth of negative buoyant jets for velocity and density are given. The calculation confirmed that the maximum height of rise is proportional to M03/4 B0-1/2, w.ere M0 and B0 are the momentum flux and the buoyancy flux at the source, respectively.

关键词： Computer simulation Jets Mathematical models Numerical methods

Effect of vehicle safety recalls on the perception tow.rds other vehicles from the same country of origin

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第5期6卷 493-503页

作者： Khaled Shaaban Amro maher Anusorn Singhapakdi Department of Civil and Architectural Engineering Qatar University Doha Qatar Beacom School of Business University of South Dakota Vermillion SD 57069 USA Department of Marketing Old Dominion University Norfolk VA 23529 USA

A vehicle safety recall significantly impacts the demand for these specific manufacturer *** effect of this recall on the other manufacturers from the same country of origin(COO) that are not involved in the recall is poorly *** purpose of this study is to examine the impact of a vehicle safety recall on other vehicle brands originating from the same *** study uses a case study related to Toyota recalls and the impact of the crises on the attitudes tow.rd three other Japanese brands-namely,Honda,Nissan,and Mazda.A questionnaire w.s conducted w.th 375 participants w.o are familiar w.th the *** findings from the questionnaire indicated that product-harm crises have an indirect negative effect on brands from the same ***,brands from the transgressor’s COO should not make the transgressor’s betrayal salient,w.ich might hurt their *** example,if Honda makes the betrayal of Toyota salient through comparative advertising,Honda’s efforts might hurt the company directly through consumers’ image of Japanese *** research should examine the extent to w.ich comparative advertising impacts non-transgressing brands that originate from the same country as the transgressing *** current results suggest that the non-transgressing companies might even assist the transgressing company to recover from such crises if consumers perceive a strong association betw.en the non-transgressing brands and transgressing brands.

关键词： Automotive recalls Vehicle safety Car accidents Vehicle defects Safety ratings

More than mimicry？ Evaluating scope for flicker-fusion as a defensive strategy in coral snake mimics

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Current Zoology 2014年第1期60卷 123-130页

作者： Georgia C. TITCOMB David w. KIKUCHI David w. PFENNIG Department of Biology University of North Carolina at Chapel Hill Chapel Hill NC 27599-3280

Coral snakes and their mimics often have brightly colored banded patterns, generally associated w.th w.rning colora- tion or mimicry. How.ver, such color patterns have also been hypothesized to aid snakes in escaping predators through a ＂flicker-fusion＂ effect. According to this hypothesis, banded color patterns confuse potential predators w.en a snake transitions from resting to moving because its bands blur together to form a different color. To produce this motion blur, a moving snake＇s bands must transition faster than the critical flicker-fusion rate at w.ich a predator＇s photoreceptors can refresh. It is unknow. if coral snakes or their mimics meet this requirement. w. tested this hypothesis by measuring the movement speed and color pat- terns of tw. coral snake mimics, Lampropeltis triangulum campbelli and L. elapsoides, and comparing the frequency of color transitions to the photoreceptor activity of the avian eye. w. found that snakes often produced a motion blur, but moving snakes created a blurring effect more often in darker conditions, such as sunrise, sunset, and nighttime w.en these snakes are often active. Thus, at least tw. species of coral snake mimics are capable of achieving flicker-fusion, indicating that their color patterns may confer an additional defense aside from mimicry

关键词： Coral snake mimicry Flicker-fusion effect CFF Kingsnake Defensive strategy

Design and Implementation of MAC Layer in 155.520Mbps Broadband Fiber Optic MAN

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High Technology Letters 1995年第1期1卷 55-60页

作者： Yanhong, w. Yaozhong, w. w.ndong, Y. Shanghai Jiao Tong Univ Shanghai China

The fiber optic technology has matured to the point w.ere Metropolitan Area Netw.rks(MAN)can be built to operate at speeds from 150Mbps to more than *** paper in-troduces an experimental fiber optic *** topology of this MAN is an open looped dualbus,and the data rate at each bus is 155.520 *** apply ATM technique and modified802.6 DQDB MAC protocol,using universal packet *** cell format is completelycompatible w.th B-ISDN *** gatew.y the MAN can be interconnected w.th theBroadband Data Microw.ve Netw.rk,VSAT,Satellite Broadcast TV System,and *** are up to 254 nodes connecting to the netw.rk,and the distance betw.en tw. ad-jacent nodes covers more than 5 *** use 1.3μm SMF as the transmission *** paper emphasizes on the design and implementation of the Medium Access Control(MAC)Protocol.

关键词： Metropolitan area netw.rk Modified distributed queue dual bus Medium access control

Shedding light on electrodeposition dynamics tracked in situ via soft X-ray coherent diffraction imaging

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Nano Research 2016年第7期9卷 2046-2056页

作者： George Kourousias Benedetto Bozzini Alessandra Gianoncelli michael w. M. Jones Mark Junker Grant van Riessen Maya Kiskinova Elettra Sincrotrone Trieste ScpA SS 14-km 163.5 in Area Science Park 34149 Trieste ltaly Dipartimento di Ingegneria dell'lnnovazione Universita del Salento via Monteroni 73100 Lecce Italy Australian Synchrotron Clayton 3168 Australia ARC Centre of Excellence for Advanced Molecular Imaging La Trobe Institute of Molecular Science La Trobe University Bundoora 3089 Australia Department of Chemistry and Physics La Trobe Institute for Molecular Science La Trobe University Bundoora 3086 Australia

The in situ physicochemical analysis of nanostructured functional materials is crucial for advances in their design and production. X-ray coherent diffraction imaging （CDI） methods have recently demonstrated impressive potential for characterizing such materials w.th a high spatial resolution and elemental sensitivity; how.ver, moving from the current ex situ static regime to the in situ dynamic one remains a challenge. By combining soft X-ray ptychography and single-shot keyhole CDI, w. performed the first in situ spatiotemporal study on an electrodeposition process in a sealed w.t environment, employed for the fabrication of oxygen-reduction catalysts, w.ich are key components for alkaline fuel cells and metal-air batteries. The results provide the first experimental demonstration of theoretically predicted Turing-Hopf electrochemical pattern formation resulting from morphochemical coupling, adding a new.dimension for the in-depth in situ characterization of electrodeposition processes in space and time.

关键词： in situ electrodeposition X-ray coherent diffractionimaging keyhole coherentdiffraction imaging (CDI) X-ray ptychography

Is a nanorod (or nanotube) w.th a low.r Young’s modulus stiffer? Is not Young’s modulus a stiffness indicator?

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Science China(Physics,Mechanics & Astronomy) 2010年第4期53卷 712-724页

作者： Lim C. w. Department of Building and Construction City University of Hong Kong

It has been a know. fact in classical mechanics of materials that Young’s modulus is an indicator of material stiffness and materials w.th a higher Young’s modulus are stiffer. At the nanoscale, w.thin the scope and under specific circumstances described in this paper, how.ver, a nanorod (or a nanotube) w.th a smaller Young’s modulus (smaller stress-strain rate) is stiffer. In such a scenario, Young’s modulus is not a stiffness indicator for nanostructures. Furthermore, the nonlocal stress-strain rate is dependent on types of load, boundary conditions and location. This is likely to be one of the many possible reasons w.y numerous experiments in the past obtained significantly varying values of Young’s modulus for a seemingly identical nanotube, i.e. because the types of loading and/or boundary conditions in the experiments w.re different, as w.ll as at w.ich point the property w.s measured. Based on the nonlocal elasticity theory and w.thin the scope of material and geometric linearity, this paper reports the strange and hitherto unrealized effect that a nanorod (or a nanotube) w.th a low.r Young’s modulus (smaller stress-strain rate) indicates smaller extension in tensile analysis. Similarly, it is also predicted that a nanorod (or a nanotube) w.th a low.r Young’s modulus results in smaller bending deflection, higher critical buckling load, higher free vibration frequency and higher w.ve propagation velocity, w.ich are at all consequences of a stiffer nanostructure.

关键词： nanorod nanotube nonlocal stress nonlocal elasticity stiffness tensile Young’s modulus

Grain-size records at ODP Site 1146 from the northern South China Sea: Implications on the East Asian monsoon evolution since 20 Ma

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Science China Earth Sciences 2007年第10期50卷 1536-1547页

作者： Jan-Berend w. STUUT Research Center Ocean Margins Bremen University Bremen 28334 Germany

273 samples from Ocean Drilling Program (ODP) Site 1146 in the northern South China Sea (SCS) w.re analyzed for grain-size distributions using grain-size class vs. standard deviation method and end-member modeling algorithm (EMMA) in order to investigate the evolution of the East Asian monsoon since about 20 Ma. 10–19 μm/1.3–2.4 μm, the ratio of tw. grain-size populations w.th the highest variability through time w.s used to indicate East Asian w.nter monsoon intensity relative to summer monsoon. The mass accumulation rate of the coarsest end member EM1 (eolian), resulting from EMMA, can be used as a proxy of w.nter monsoon strength and Asian inland aridity, and the ratio of EM1/(EM2+EM3) as a proxy of w.nter monsoon intensity relative to summer monsoon. The combined proxies show.that a profound enhancement of East Asian w.nter monsoon strength and w.nter monsoon intensity relative to summer monsoon occurred at about 8 Ma, and it is possible that the summer monsoon simultaneously intensified w.th w.nter monsoon at 3 Ma. Our results are w.ll consistent w.th the previous studies in loess, eolian deposion in the Pacifc, radiolarians and planktonic foraminifera in the SCS. The phased uplift of the Himalaya-Tibetan Plateau may have played a significant role in strengthening the Asian monsoon at 8 Ma and 3 Ma.

关键词： grain size, eolian dust, East Asian monsoon, South China Sea, ODP Leg184