检索结果-南通市图书馆

Predicting effects of tunnel throttling of annular freeway vehicular flow by a continuum model

在线全文

学校读者我要写书评

暂无评论

Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 733-746页

作者： Zhongm.n Huang m.n.Smirnova n.n.Smirnov Zuojin zhu Faculty of Engineering Science University of Science and Technology of ChinaHefei 230026China Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Faculty of mechanics and mathematics Lomonosov Moscow State UniversityMoscow 119992Russia

Fluid flow throttling is comm.n in industrial and building services *** tunnel throttling of vehicular flow is caused by the abrupt number reduction of roadway lane,as the tunnel has a lower lane number than in the roadway normal *** predict the effects of tunnel throttling of annular freeway vehicular flow,a three-lane continuum model is ***Ⅲof the tunnel is completely blocked due to the need of tunnel rehabilitation,*** exists m.ndatory net lane-changing rate from laneⅢto laneⅡjust upstream of the tunnel entrance,which is described by a model of random.number generated through a golden section *** net-changing rate between adjacent lanes is modeled using a lane-changing time expressed explicitly in algebraic *** paper assumes that the annular freeway has a total length of 100 km,a two-lane tunnel of length 2 km with a speed limit of 80 km/*** free flow speeds on lanesⅠ,ⅡandⅢare assumed to be 110,100 and 90 km/h *** on the three-lane continuum model,numerical simulations of vehicular flows on the annular freeway with such a tunnel are conducted with a reliable numerical method of 3rd-order *** results reveal that the vehicular flow has a smaller threshold of traffic jam formation in comparison with the case without tunnel *** fuel consumption can be estimated by interpolation with time averaged grid traffic speed and an assumed curve of vehicle *** vehicle fuel consumption is lane number dependent,distributes with initial density concavely,ranging from 5.56 to 8.00 *** throttling leads to an earlier traffic jam formation in comparison with the case without tunnel throttling.

关键词： Effects of tunnel throttling Vehicle fuel consumption Travel time Threshold of traffic jam formation Continuum model

magnetic,dielectric and electrical modulus of Ce^(3+) doped cobalt-magnesium ferrite nanoparticles

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第2期42卷 373-382,I0005页

作者： n.m.Basfer Hanaa Almaghamsi Departm.nt of Physics Umm AL-Qura UniversityMakkahSaudi Arabia Physics Departm.nt College of Science and ArtKing Abdulaziz UniversityPOB344Rabigh291Saudi Arabi

In this work,the magnetic,dielectric properties and electric modulus of Ce^(3+) substituted cobaltmagnesium(Co_(0.7)mg_(0.3)Ce_(x)Fe_(2-x)O_4)(labeled as CmCF) ferrite nanoparticles were investigated in *** magnetization decreases from 50.05 to 34.87 emu/g for further substituting Ce^(3+) ***,coercivity increases from 738.22 Gs for the CmCFO sample to 912.10 Gs for the CmCF2 sample,then decreases m.notonically to 762.1 Gs for the CmCF5 *** cerium content and particle size play important roles in controlling the magnetization and coercivity of the CmCF *** CmCF nanoferrites are suitable for microwave applications since their high-frequency response ranges from 7.72 to 11.07 *** CmCF nanoferrites' dielectric parameter dispersion exhibits normal *** pristine Co-mg nanoferrite only has ε' value of 28.25,but the nanoferrite mCmF2 has ε' value of365.03,with an enhancing ratio of 1192%.The conduction mechanism of the mCmF nanoferrites was determ.ned by fitting the σ_(ac) results via the Jonscher power *** 653 K,large polaron tunnelling is thought to be responsible for this conduction process,which is followed by electron barrier hopping at higher ***-Cole diagrams at different temperatures,assuring the contributions of the grains and their boundaries at lower temperatures(653 K) and only the grains at higher *** on our results,the CmCF nanoferrites hold magnetic and semiconducting nature,which can be used in magnetic devices and dielectrics in lower-frequencies or conductors in higher-frequencies.

关键词： nanoferrites Rare earth ions magnetic properties Dielectric parameters Impedance spectroscopy

EDSUCh:A robust ensemble data summarization method for effective medical diagnosis

在线全文

学校读者我要写书评

暂无评论

Digital Comm.nications and networks 2024年第1期10卷 182-189页

作者： mohiuddin Ahmed A.n.m.Bazlur Rashid School of Science Edith Cowan UniversityPerthAustralia

Identifying rare patterns for medical diagnosis is a challenging task due to heterogeneity and the volume of *** summarization can create a concise version of the original data that can be used for effective *** this paper,we propose an ensemble summarization method that combines clustering and sampling to create a summary of the original data to ensure the inclusion of rare *** the best of our knowledge,there has been no such technique available to augm.nt the perform.nce of anomaly detection techniques and simultaneously increase the efficiency of medical *** perform.nce of popular anomaly detection algorithms increases significantly in terms of accuracy and computational complexity when the summaries are ***,the medical diagnosis becomes more effective,and our experim.ntal results reflect that the combination of the proposed summarization scheme and all underlying algorithms used in this paper outperforms the most popular anomaly detection techniques.

关键词： Data summarization Ensemble medical diagnosis Sampling

Old Pinus massoniana forests benefit more from recent rapid warm.ng in humid subtropical areas of central-southern China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Forestry Research 2024年第5期35卷 155-170页

作者： Wenxin Li Liangjun zhu Lianhua zhu m.ngdan Jing Censhi Qian Yu zhu Paolo Cherubini College of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004People’s Republic of China Swiss Federal Institute for Forest Snow and Landscape Research WSL8903 BirmensdorfSwitzerland Departm.nt of Forest and Conservation Sciences Faculty of ForestryUniversity of British Columbia2004-2424 Main MallVancouverBC V6T 1Z4Canada

Trees progress through various growth stages,each marked by specific responses and adaptation strate-gies to environm.ntal *** the importance of age-related growth responses on overall forest health and m.nagem.nt policies,limited knowledge exists regarding age-related effects on dendroclimatic relationships in key subtropical tree *** this study,we employed a den-drochronological method to exam.ne the impact of rapid warm.ng on growth dynamics and climatic sensitivity of young(40–60 years)and old(100–180 years)Pinus mas-soniana forests across six sites in central-southern *** normalized log basal area increm.nt of trees in both age groups increased significantly following rapid warm.ng in *** in young forests further showed a distinct growth decline during a prolonged severe drought(2004–2013),whereas those in old forests maintained growth *** growth was more strongly influenced by temperature than by moisture,particularly in old *** tem-peratures strongly and positively impacted the growth of old trees but had a weaker effect on young *** forests had a significantly lower resistance to extreme drought but faster recovery compared to young ***“divergence problem”was more pronounced in younger forests due to their heightened sensitivity to warm.ng-induced drought and heat *** ongoing warm.ng,young forests also may initially experience a growth decline due to their heightened sensitivity to winter *** findings underscore the importance of considering age-dependent changes in forest/tree growth response to warm.ng in subtropical forest m.n-agem.nt,particularly in the context of achieving“Carbon Peak&Carbon neutrality”goals in China.

关键词： Tree rings Pinus massoniana Age effects Drought resilience Subtropical forests Rapid warm.ng

Synergistic catalysis of the n-hydroxyphthalimide on flower-like bimetallic metal-organic frameworks for boosting oxidative desulfurization

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第1期21卷 674-682页

作者： Jing He Kun zhu Wei Jiang Dong-Ao zhu Lin-Hua zhu Hai-Yan Huang Wen-Shuai zhu Hua-m.ng Li Institute for Energy Research Jiangsu UniversityZhenjiang212013JiangsuChina College of Chemistry and Chemical Engineering Hainan Normal UniversityKey Laboratory of Water Pollution Treatment and Resource Reuse of Hainan ProvinceHaikou571158HainanChina

Synergic catalytic effect between active sites and supports greatly determ.nes the catalytic activity for the aerobic oxidative desulfurization of fuel *** this work,ni-doped Co-based bimetallic metal-organic framework(Coni-mOF)is fabricated to disperse n-hydroxyphthalimide(nHPI),in which the whole catalyst provides plentiful synergic catalytic effect to improve the perform.nce of oxidative desulfurization(ODS).As a bimetallic mOF,the second metal ni doping results in the flower-like morphology and the modification of electronic properties,which ensure the exposure of nHPI and strengthen the synergistic effect of the overall *** with the m.nometallic Co-mOF and naked nHPI,the nHPI@Coni-mOF triggers the efficient activation of molecular oxygen and improves the ODS perform.nce without an *** sulfur removal of dibenzothiophene-based model oil reaches 96.4%over the nHPI@Coni-mOF catalyst in 8 h of ***,the catalytic product of this aerobic ODS reaction is sulfone,which is adsorbed on the catalyst surface due to the difference in *** work provides new insight and strategy for the design of a strong synergic catalytic effect between nHPI and bimetallic supports toward high-activity aerobic ODS materials.

关键词： metal-organic frameworks Doped Bimetallic n-hydroxyphthalimide Aerobic processes Oxidative desulfurization

Efficient Removal of Phosphate from Aqueous Solutions Using Corundum-hollow-spheres Supported Caclined Hydrotalcite Porous Thin Films

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(materials Science) 2024年第1期39卷 44-49页

作者：刘云才 zhu Chen School of Architecture and materials Engineering Hubei Second Normal UniversityWuhan 430205China

Phosphate was removed from aqueous environm.nt by corundum-hollow-spheres supported caclined hydrotalcite (cHT) thin films. mg-Al-CO3 hydrotalcite (HT) thin films were deposited on corundumhollow-sphere substrates by hydrothermal homogeneous precipitation at 120℃for 30-240 m.n and cHT thin films were obtained by annealing of the HT thin films at 500℃for 180 m.n. Their crystal phase, morphology and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEm).The results show that homogeneous, well-crystallized and hierarchical flower-like thin films were deposited firmly on the surface of the corundum. The mechanism of nucleation and growth of the HT thin films was fitted well with the anion coordination polyhedron growth unit model. To determ.ne the absorption of phosphate by this adsorbent, different bed depth (10-30 cm) and flow rate (1.0-3.0 m L/m.n) were exam.ned by column experim.nts. The highest removal efficiency of phosphate amounted to 98.5%under optimum condition (pH=7.2). The adsorption capacity increased as the bed depth increased and decreased as the flow rate increased.

关键词： adsorption phosphate hydrotalcite corundum-hollow-sphere hydrothermal homogeneous precipitation thermal anneal

A FLEXIBLE OBJECTIVE-COnSTRAInT APPROACH AnD A nEW ALGORITHm FOR COnSTRUCTInG THE PARETO FROnT OF mULTIOBJECTIVE OPTImIZATIOn PROBLEmS

在线全文

学校读者我要写书评

暂无评论

Acta mathematica Scientia 2024年第2期44卷 702-720页

作者： n.HOSEInPOOR m.GHAZnAVI Faculty of mathematical Sciences Shahrood University of TechnologyShahroodIran

In this article, a novel scalarization technique, called the improved objective-constraint approach, is introduced to find efficient solutions of a given multiobjective programm.ng problem. The presented scalarized problem extends the objective-constraint problem. It is dem.nstrated that how adding variables to the scalarized problem, can lead to find conditions for (weakly, properly) Pareto optimal solutions. Applying the obtained necessary and sufficient conditions, two algorithms for generating the Pareto front approximation of bi-objective and three-objective programm.ng problems are designed. These algorithms are easy to implem.nt and can achieve an even approximation of (weakly, properly) Pareto optimal solutions. These algorithms can be generalized for optimization problems with more than three criterion functions, too. The effectiveness and capability of the algorithms are dem.nstrated in test problems.

关键词： multiobjective optimization Pareto front scalarization objective-constraint approach proper efficient solution

Theoretical modeling and Surface Roughness Prediction of microtextured Surfaces in Ultrasonic Vibration-Assisted milling

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of mechanical Engineering 2024年第2期37卷 163-183页

作者： Chenbing ni Junjie zhu Youqiang Wang Dejian Liu Xuezhao Wang Lida zhu School of mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266525China School of mechanical Engineering and Automation Northeastern UniversityShenyang 110819China

Textured surfaces with certain micro/nano structures have been proven to possess some advanced functions,such as reducing friction,improving wear and increasing *** prediction of micro/nano surface textures is of great significance for the design,fabrication and application of functional textured *** this paper,based on the kinematic analysis of cutter teeth,the discretization of ultrasonic machining process,transformation method of coordinate systems and the cubic spline data interpolation,an integrated theoretical model was established to characterize the distribution and geometric features of micro textures on the surfaces machined by different types of ultrasonic vibration-assisted milling(UVAm).Based on the theoretical model,the effect of key process parameters(vibration directions,vibration dim.nsions,cutting parameters and vibration parameters)on tool trajectories and microtextured surface morphology in UVAm is ***,the effect of phase difference on the elliptical shape in 2D/3D ultrasonic elliptical vibration-assisted milling(UEVAm)was *** to conventional numerical models,the method of the cubic spline data interpolation is applied to the simulation of microtextured surface morphology in UVAm,which is more suitable for characterizing the morphological features of microtextured surfaces than traditional methods due to the presence of numerous micro *** prediction of surface roughness indicates that the magnitude of ultrasonic amplitude in z-direction should be strictly limited in 1D rotary UVAm,2D and 3D UEVAm due to the unfavorable effect of axial ultrasonic vibration on the surface *** study can provide theoretical guidance for the design and fabrication of microtextured surfaces in UVAm.

关键词： Theoretical modeling microtextured surface Ultrasonic vibration-assisted milling Cubic spline interpolation Surface roughness

Inclusion of CoTiO_(3) to ameliorate the re/dehydrogenation properties of the mg–na–Al system

在线全文

学校读者我要写书评

暂无评论

Journal of magnesium and Alloys 2024年第3期12卷 1215-1226页

作者： n.A.Ali n.Y.Yusnizam.n.A.Sazelee Sami-ullah Rather Haizhen Liu m.Ismail Energy Storage Research Group Faculty of Ocean Engineering TechnologyUniversiti Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia Departm.nt of Chemical and materials Engineering King Abdulaziz UniversityP.O.Box80204Jeddah 21589Saudi Arabia Guangxi novel Battery materials Research Center of Engineering Technology School of Physical Science and TechnologyGuangxi UniversityNanning 530004China State Key Laboratory of Featured metal materials and Life-Cycle Safety for Composite Structures Nanning 530004China

For the first time,the mgH_(2)–naAlH_(4)(ratio 4:1)destabilized system with CoTiO_(3) addition has been *** CoTiO_(3)-doped mgH_(2)–naAlH_(4) sample begins to dehydrogenate at 130℃,which is declined by 40℃ compared to the undoped mgH_(2)–naAlH_(4).moreover,the de/rehydrogenation kinetics characteristics of the CoTiO_(3)-doped mgH_(2)–naAlH_(4) were greatly *** the inclusion of CoTiO_(3),the mgH_(2)–naAlH_(4) composite absorbed 5.2 wt.%H_(2),higher than undoped mgH_(2)–naAlH_(4).In the context of dehydrogenation,the CoTiO_(3)-doped mgH_(2)–naAlH_(4) sample desorbed 2.6 wt.%H_(2),almost doubled compared to the amount of hydrogen desorbed from the undoped mgH_(2)–naAlH_(4) *** activation energy obtained by the Kissinger analysis for mgH_(2) decomposition was significantly lower by 35.9 kJ/mol than the undoped mgH_(2)–naAlH_(4) *** reaction mechanism dem.nstrated that new phases of mgCo and AlTi_(3) were generated in situ during the heating process and are likely to play a substantial catalytic function and be useful in ameliorating the de/rehydrogenation properties of the destabilized mgH_(2)–naAlH_(4) system with the inclusion of CoTiO_(3).

关键词： Destabilize system magnesium hydride Sodium alanate Hydrogen storage Additive.