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Investigation on the Formation of Herringbone Structure in TypeⅡSolar Radio Bursts

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Research in Astronomy and Astrophysics 2023年第5期23卷 101-109页

作者： z.z.Abidin A.N.zulkiplee V.Epin F.A.m.Pauzi Radio Cosmology Research Lab Physics Dept.Faculty of ScienceUniversity of MalayaKuala LumpurMalaysia

We report detailed observation of the“herringbone”of a Type II solar radio burst that occurred on 2010 November *** from the Space Weather Prediction Center,National Oceanic and Atmospheric Administration,e-CALLISTO,and Nan?ay Radio Heliograph are *** determine the brightness temperature and degree of circular polarization of the“herringbone”*** between the physical parameters and the“herringbone”are *** on the relationship,this is the first study that suggested this“herringbone”was generated through fundamental plasma.

关键词： Sun activity-Sun corona-Sun coronal mass ejections(CmEs)-Sun magnetic fields-Sun radio radiation

Optimal Coordination of Transportable Power Sources and Repair Crews for Service Restoration of Distribution Networks Considering Uncertainty of Traffic Congestion

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Journal of modern Power Systems and Clean Energy 2024年第1期12卷 189-201页

作者： zhao shi Yan Xu Dunjian Xie shiwei Xie Amer m.Y.m.Ghias Nanyang Technological University Singapore the School of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China

This paper proposes a new method for service restoration of distribution network with the support of transportable power sources(TPSs)and repair crews(RCs).Firstly,a coupling model of distribution networks and vehicle routing of TPSs and RCs is proposed,where the TPSs serve as emergency power supply sources,and the RCs are used to repair the faulted *** the uncertainty of traffic congestion,the probability distribution of the travel time spent on each road is derived based on the Nesterov user equilibrium model,and a two-stage stochastic program is formulated to determine the optimal routings of TPSs and *** efficiently solve the proposed stochastic mixed-integer linear program(mILP),a two-phase scenario reduction method is then developed to scale down the problem size,and an adaptive progressive hedging algorithm is used for an efficient *** effectiveness of the proposed methods and algorithms has been illustrated in a modified IEEE 33-bus system.

关键词： Service restoration distribution network traffic uncertainty transportable power source repair crew stochastic program

An Investigation on the Formation of Submerged Bar Under Surges in Sandy Coastal Region

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China Ocean Engineering 2012年第3期26卷 535-546页

作者： mustafa DEmIRCI m.Sami AKz Civil Engineering Department Engineering FacultyMustafa Kemal UniversityskenderunHatay 31040Turkey Civil Engineering Department Engineering and Architecture Facultyukurova UniversityAdana 01100Turkey

Cross-shore sediment transport rate exposed to waves is very important for coastal morphology, the design of marine structures such as seawalls, jetties, breakwaters etc, and the prevention of coastal erosion and accretion due to onoff shore sediment transportation. In the present study, the experiments on cross-shore sediment transport are carried out in a laboratory wave channel with initial beach slopes of 1/8, 1/10 and 1/15. By using the regular waves with different deep-water wave steepnesses generated by a pedal-type wave generator, the geometrical characteristics of beach profiles under storm conditions and the parameters affecting on-off shore sediment transport are investigated for the beach materials with medium diameters of d50=0.25, 0.32, 0.45, 0.62 and 0.80 mm. The offshore bar geometric characteristics are the horizontal distances from the shoreline to the bar beginning （Xb）, crest （Xt）, and ending （Xs） points, the depth from the bar crest to the still water level （ht）, and the bar volume （Vbar）. The experimental results have indicated that when the deep-water steepness （Ha/L0） increased, the net movement to seaside increased. With the increasing wave steepness, the bars moved to widen herewith the vertical distances from still water level to the bar beginning （Xb）, crest （Xt） and ending （Xs） points and the horizontal distances from the coast line to the bar beginning, crest and ending points increased. It was also shown from experimental results that the horizontal distances from the bar beginning and ending points to the coast line increased with the decrease of the beach slope. The experimental results obtained from this study are compared with previous experimental work and found to be of the same magnitude as the experimental measurements and followed the expected basic trend.

关键词： cross-shore sediment transport beach profiles bar parameters experimental study

NUmERICAL STUDY OF THE NOTCH EFFECT ON THE CREEP BEHAVIOR AND LIFE OF NICKEL-BASE SINGLE CRYSTAL SUPERALLOYS

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Acta metallurgica Sinica(English Letters) 2004年第4期17卷 487-492页

作者： Q.m.Yu z.F.Yue Department of Engineering mechanics Northwestern Polytechnical University Xi'an 710072 ChinaDepartment of Engineering Mechanics Northwestern Polytechnical University Xi'an 710072 China

Numerical calculations of creep damage development and life behavior of circular notched specimens of nickel-base single crystal had been performed. The creep stress distributions depend on the specimen geometry. For a small notch radius, von mises stress has an especial distribution. The damage distribution is greatly influenced by the notch depth, notch radius as well as notch type. The creep crack initiation place is different for each notched specimen. The characteristics of notch strengthening and notch weakening depend on the notch radius and notch type. For the same notch type, the creep rupture lives decrease with the decreasing of notch radius. A creep life model has been presented for the multiaxial stress states based on the crystallographic slip system theory.

关键词： creep damage life model notched specimen nickel-base single crystal superalloys

An update on the diagnosis of gastroenteropancreatic neuroendocrine neoplasms

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World Journal of Gastroenterology 2022年第10期28卷 1009-1023页

作者： Jiayun m Fang Jay Li Jiaqi shi Department of Pathology&Clinical Labs University of MichiganAnn ArborMI 48109United States medical Scientist Training Program University of MichiganAnn ArborMI 48109United States

Gastroenteropancreatic neuroendocrine neoplasms(GEP-NENs)arise from neuroendocrine cells found throughout the gastrointestinal tract and islet cells of the *** incidence and prevalence of GEP-NENs have been increasing each year due to higher awareness,improved diagnostic modalities,and increased incidental detection on cross-sectional imaging and endoscopy for cancer screening and other conditions and ***-NENs are a heterogeneous group of tumors and have a wide range in clinical presentation,histopathologic features,and molecular *** presentation most commonly depends on whether the GEP-NEN secretes an active *** World Health Organization recently updated the classification of GEP-NENs to introduce a distinction between high-grade neuroendocrine tumors and neuroendocrine carcinomas,which can be identified using histology and molecular studies and are more aggressive with a worse prognosis compared to high-grade neuroendocrine *** our understanding of the biology of GEP-NENs has grown,new and improved diagnostic modalities can be developed and ***,we discuss clinical features and updates in diagnosis,including histopathological analysis,biomarkers,molecular techniques,and radiology of *** review established diagnostic tests and discuss promising novel diagnostic tests that are currently in development or require further investigation and validation prior to broad utilization in patient care.

关键词： Neuroendocrine tumor Neuroendocrine carcinoma Gastrointestinal Pancreas Pathology Diagnosis

Collaborative Supply Chain management: A Critical Redesigning Factor

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厦门大学学报（自然科学版） 2002年第S1期41卷 257-258页

作者： z m Udin Department of mechanical and medical Engineering

In improving the competitiveness of business organi sa tion in the 21st century, minimising cost and increasing productivity are no lon ger factors that could promise the success. The changes in customer trends whic h focusing more on product or service customising, high quality and short delive ry times are additional crucial factors that organisation should be aware of. T hese factors have direct relations on how the management could utilise the capab ility of its supply chain management (SCm). The importance of SCm in organisati on specifically to manufacturer is to play a vital role in managing the flow of material and information along the chain from suppliers to customers. In a trad itional way, SCm is mainly manage by the production department in organisation b ut with the advancement in information technology, resulted the changes in worki ng environment. One of the ways that could be implemented in decision making p rocess in order to improve the effectiveness and efficiency of the decision is t hrough collaborative environment. Due to this situation, there is a need to rede sign the existing SCm in order to optimise its capability and functionality in t he way to ensure the organisation competitiveness is sustainable. A minor or ma jor alignment to SCm business processes should be done in order to streamline th e flow of information, which could also affect the flow of materials. Factors s uch as SCm operational, structural and even its managerial are among the issues that are critical in redesigning its business process. Each of these factors has its own attributes such as lead-times, complexity, frequency and organisationa l setting that could lead in improving organisational competitiveness. In additi on, by identifying these factors, it would help the management to plan and desig n the collaborative SCm that would effectively correspond to the changes in busi ness and customer trends. The intention of the paper is to promote a list of fa ctors and attr

关键词： SCm A Critical Redesigning Factor Collaborative Supply Chain management

REAL-TImE FLOOD FORECASTING mODELING OF 1D UNSTEADY CHANNEL FLOW AND KALmAN FILTER

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Journal of Hydrodynamics 2001年第1期13卷 64-69页

作者： Li, z.J. Weng, m.H. Coll. of Water Res. and Environ. Hohai Univ. Nanjing 210024 China

The model of 1D unsteady channel flow combined with the Kalman filter for real-time channel flood forecasting was attempted. The suitable upstream and downstream boundary conditions were suggested. The system equation was given by the linearization of the finite difference equations of the mass conservation and momentum equations as well as the boundary conditions. In the Kalman filter updating model, because the number of measurement variable is less than that of state-space variables, the measurement error covariance matrix could be estimated in real time through the innovation sequence, and the system error covariance matrix needs to be estimated preliminarily. A real example of flood forecasting in the Huaihe River was given to explain how the method works. The results show that the model is reasonable and effective.

关键词： Channel flow Computer simulation Kalman filtering Unsteady flow

Axisymmetric Stagnation-Point Flow with a General Slip Boundary Condition over a Lubricated Surface

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Chinese Physics Letters 2012年第2期29卷 126-129页

作者： m.Sajid K.mahmood z.Abbas The Abdus Salam International Centre for Theoretical Physics Strada Costiera 1134014TriesteItaly Department of mathematics Riphah International UniversityIslamabad 44000Pakistan Department of mathematics The Islamia University of BahawalpurBahawalpurPakistan

We investigate the axisymmetric stagnation-point flow of a viscous fluid over a lubricated surface by imposing a generalized slip condition at the fluid-fluid *** power law non-Newtonian fluid is considered as a *** lubrication layer is thin and assumed to have a variable *** transformed nonlinear ordinary differential equation governing the flow is linearized using *** method of superposi-tion is adopted to convert the boundary value problem into an initial value problem and the solution is obtained numerically by using the fourth-order Runge-Kutta *** results are discussed to see the influence of pertinent *** limiting cases of Navier and no-slip boundary conditions are obtained as the special cases and found to be in excellent agreement with the existing results in the literature.

关键词： boundary ordinary assumed

mechanisms behind the environmental sensitivity of carbon fiber reinforced polytetrafluoroethylene(PTFE)

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Friction 2024年第5期12卷 997-1015页

作者： Pontus JOHANSSON P.mARKLUND m.BJORLING Y.shi Division of machine Element LuleåUniversity of TechnologyLuleåSE-97187Sweden

Carbon fiber reinforced polytetrafluoroethylene (CF/PTFE) composites are known for their exceptional tribological performance when sliding against steel or cast iron in inert gas environments. Compared to experiments in humid air, about an order of magnitude lower wear rate and several times lower coefficient of friction have been reported for tests conducted in dry nitrogen and hydrogen. moreover, trace moisture has been shown to affect the friction and wear significantly of this tribosystem, although a possible effect of oxygen cannot be ruled out due to uncertainties regarding the oxygen concentrations. While several studies have pointed out the environmental sensitivity of CF/PTFE, the understanding of the underlying mechanisms are very limited. The objective of this research is to investigate the individual and combined effect of oxygen and moisture on the tribological behavior of CF/PTFE sliding against steel. Additionally, this study aims to elucidate the underlying mechanisms that govern the environmental sensitivity of the system. Climate-controlled three-pin-on-disc experiments were conducted in nitrogen atmospheres at various concentrations of oxygen and moisture. The tribological results clearly demonstrate that both moisture and oxygen contribute to increased friction and wear. However, the adverse effect was much more pronounced for oxygen than moisture. A qualitative method was developed to estimate the tribofilm coverage on the CF/PTFE surface. Results showed strong correlation between high coverage of strongly adhered tribofilm and low wear rate. moreover, a loosely adhered tribofilm was observed on top of the CF/PTFE surface in presence of moisture. FTIR analysis indicated that the loosely adhered tribofilm found in the moisture-enriched environment contained a significant amount of adsorbed water, which may explain the lower coefficient of friction in presence of moisture compared to oxygen. The adsorbed water in the loosely adhered tribofilm coul

关键词： polymer composite tribofilm tribochemistry atmosphere