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Parking choice behaviour analysis of rural residents based on the latent variable random forest model

Transportation Safety and Environment 2024年第3期6卷 167-180页

作者： Minqing zhu bo Zhao Hongjun Cui Sheng Yao feng Xu School of Architecture and Art Design Hebei University of TechnologyTianjin 300130China School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China

The imbalance of rural parking supply and demand has a great impact on traffic congestion and environmental pollution,which has attracted the attention of many scholars as well as ***,most of the current research on parking choice focuses on urban business and residential areas rather than on rural parking choice behaviour,and focuses on the analysis of observable factors,ignoring the internal relationship with potential *** study considers the heterogeneity of individuals and uses the random forest(RF)algorithm to construct a model of rural residents’willingness to choose parking with both latent and explicit variables,to explore how much and in what ways individual characteristics and parking characteristics affect rural residents’parking choices,and to explore parking planning programmes and strategies that are truly applicable to rural *** results of the study suggest that the safety and convenience of the parking environment are key factors influencing the parking choice behaviour of rural residents,and can greatly improve the predictive accuracy of the parking willingness *** comparison,it is found that the application of the RF algorithm is also significantly better than the logit model in terms of prediction effect,indicating that there is a nonlinear effect among the factors influencing the parking choice behaviour of rural residents and that the RF model with the addition of latent variables provides a better explanatory ability for the study of the parking choice behaviour of rural residents.

关键词： rural residents parking choice random forest(RF) latent variable SEM-RF model

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Radio jets and galaxies as cosmic string probes

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Frontiers of physics 2012年第4期7卷 461-470页

作者： Fa-bo feng Department of Astronomy Nanjing UniversityNanjing 210093China

The lensing effect of a cosmic string is studied, and some new methods are proposed to detect the cosmic string. The technique for using jets as extended gravitational lensing probes was first explored by Kronberg. We use the ＂alignment-breaking parameter＂ nc as a sensitive indicator of gravitational distortion by a wiggly cosmic string. Then, we applied the non-constant deflection angle to jets, and na of a specific jet is just related to the projected slope of the jet. At least three jets in the sample of Square Kilometer Array （SKA） would have significant signals （na 〉 10°） if the wiggly infinite cosmic string existed. The distortion of elliptical object is also studied and used to do a statistical research on the directions of axes and ellipticities of galaxies. In the direction of the string, we find that galaxies appear to be more elliptical for an observer and the distribution of apparent ellipticity changes correspondingly. The ellipticity distribution of current SDSS spiral sample has the signal- to-noise ratio up to 8.48 which is large enough for astronomical observations. The future survey, such as Large Synoptic Survey Telescope （LSST） and Dark Energy Survey （DES） would weaken the requirement of special geometry in the data processing. As a result, all kinds of distributions, including ellipticity axis distribution, would serve as probes to detect wiggly strings in the near future. In brief, if a wiggly cosmic string existed, these signals would be convenient to be observed with the future weak lensing survey or other surveys in the deep space. If there was no lensing signal in these distributions, it would give the upper limit of the abundance of infinite strings.

关键词： gravitational lensing jets and outflows cosmic string galaxy

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Flight Schedule Recovery under Uncertain Airport Capacity

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第4期33卷 479-490页

作者： zhu bo zhu Jinfu College of Civil Aviation Nanjing University of Aeronautics and Astronautics

Airlines adjust their flight schedules to satisfy more stringent airport capacity constraints caused by inclement weather or other unexpected *** problem will be more important and complicated if uncertain disruptions occur in hub airports.A two-stage stochastic programming model was established to deal with the realtime flight schedule recovery and passenger re-accommodation *** first-stage model represents the flight re-timing and re-fleeting decision in current time period when capacity information is deterministic,while the second-stage recourse model evaluates the passenger delay given the first-stage solutions when one future scenario is *** at the large size of the problem and requirement for quick response,an algorithmic framework combining the sample average approximation and heuristic method was *** computational results indicated of that the proposed method could obtain solutions with around 5% optimal gaps,and the computing time was linearly positive to the sample size.

关键词： flight recovery passenger re-accommodation two-stage stochastic model sample average approximation heuristic method

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Analysis of the anti-T2DM components in dichloromethane fraction of Schisandra sphenanthera and its mechanism

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Traditional Medicine Research 2025年第1期10卷 27-43页

作者： Shi-bo feng Hai-Hui Jiang Hui-Li Kang Yi Jiang Hua-Wei Zhang Xiao-Mei Song Yu-Ze Li Wen-Li Huang Dong-Dong Zhang Chong Deng School of Pharmacy Shaanxi University of Chinese MedicineXianyang 712046China School of Pharmacy and Shaanxi Qinling Application Development and Engineering Center of Chinese Herbal Medicine Shaanxi University of Chinese MedicineXianyang 712046China Key Laboratory for Research and Development of“Qin Medicine”of Shaanxi Administration of Traditional Chinese Medicine Xianyang 712046China Shaanxi Key Laboratory of Research and Application of“Taibai Qi Yao” Xianyang 712046China

Background:The type 2 diabetes mellitus(T2DM)pharmacodynamic study of various parts of Schisandra sphenanthera was conducted in the previous stage,and it was found that dichloromethane extracted part(SDP)had a significant hypoglycemic ***,the components of SDP were analyzed,and the specific mechanism of its anti-T2DM was ***:We used a high-fat,high-sugar diet in combination with streptozotocin to induce a T2DM rat model,and the model rats were divided into two groups according to body weight and blood ***,oral glucose tolerance test,fasting blood glucose,low density lipoprotein cholesterol,superoxide dismutase,insulin,glycated hemoglobin,total cholesterol,nonesterified free fatty acids,alanine aminotransferase,high-density lipoprotein cholesterol,aspartate aminotransferase,malondialdehyde,and glutathione peroxidase were measured,organ indices were calculated,and pathological sections of pancreas and liver were *** 16S rRNA V3–V4 region of intestinal flora was sequenced to explore the effect of SDP on biochemical indicators and intestinal *** on the above indicators,the anti-T2DM mechanism of SDP in Schisandra sphenanthera was ***:After six weeks of administration,the biochemical indices of diabetic rats were diminished compared to the control *** SDP could significantly increase the gut microbialα-diversity index,resulting in significant changes in the flora of T2DM rats,with increased richness and diversity,reduced harmful flora,and significantly back-regulated the levels of acetic acid,propionic acid,and butyric ***:SDP can improve the symptoms associated with elevated blood glucose,dyslipidemia,elevated fasting insulin levels,and damaged glucose tolerance in *** against T2DM may be through the control of intestinal flora to normalize and exert anti-diabetic effect;its main active components may be lignans and terpenoids.

关键词： Schisandra sphenanthera T2DM intestinal flora HPLC

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The influence of grounded electrode positions on the evolution and characteristics of an atmospheric pressure argon plasma jet

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Plasma Science and Technology 2017年第6期19卷 3-9页

作者： bo ZHANG Ying zhu feng LIU Zhi FANG College of Electrical Engineering and Control Science Nanjing Tech University Nanjing 211816 People's Republic of China

An atmospheric pressure plasma jet（APPJ） in Ar with various grounded electrode arrangements is employed to investigate the effects of electrode arrangement on the characteristics of the *** and optical methods are used to characterize the plasma *** discharge modes of the APPJ with respect to applied voltage are studied for grounded electrode positions of 10 mm,40 mm and 80 mm,respectively,and the main discharge and plasma parameters are *** is shown that an increase in the distance between the grounded electrode and high-voltage electrode results in a change in the discharge modes and discharge *** discharges transit from having two discharge modes,dielectric barrier discharge（DBD） and jet,to having three,corona,DBD and jet,with increase in the distance from the grounded to the high-voltage *** maximum length of the APPJ reaches 3.8 cm at an applied voltage of 8 *** discharge power and transferred charges and spectral line intensities for species in the APPJ are influenced by the positions of the grounded electrode,while there is no obvious difference in the values of the electron excited temperature（EET） for the three grounded electrode positions.

关键词： grounded electrode discharge evolution discharge parameters electric field,plasma jet

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Structures and macrosegregation of a 2024 aluminum alloy fabricated by direct chill casting with double cooling field

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China Foundry 2022年第1期19卷 1-8页

作者： Cheng zhu Zhi-hao Zhao Qing-feng zhu Gao-song Wang Yu-bo Zuo Gao-wu Qin Research Center for Metallic Wires School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Key Laboratory of Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819China

Central region coarse grains and centerline segregation are common defects in aluminum ingots fabricated by direct chill(DC)casting.A double cooling field was introduced into the DC casting process to reduce these defects,whereby the external cooling was supplied by the mold and water jets,and intercooling was achieved by inserting a rod of the same alloy into the molten pool along the central axis of the *** than forming a good metallurgical interface during solid-liquid compound casting,in the present work,the purpose of inserting the rod is to enforce internal cooling and consequently decrease the sump ***,the insertion provides more nucleation sites with the unmoltenα-Al *** structure and the macrosegregation of 2024 Al alloy ingots prepared by DC casting with and without the inserts were *** show that when the inserting position is 50 mm above the upper edge of the graphite ring,significant grain refinement in the central region of the ingot and a reduced centerline segregation are achieved.

关键词： aluminum alloy direct chill casting double cooling field grain refinement macrosegregation

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Radio frequency interference mitigation using pseudoinverse learning autoencoders

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Research in Astronomy and Astrophysics 2020年第8期20卷 121-128页

作者： Hong-feng Wang Mao Yuan Qian Yin Ping Guo Wei-Wei zhu Di Li Si-bo feng Image Processing and Pattern Recognition Laboratory School of Artificial IntelligenceBeijing Normal UniversityBeijing 100875China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Information Management Dezhou UniversityDezhou 253023China Image Processing and Pattern Recognition Laboratory School of System ScienceBeijing Normal UniversityBeijing 100875China Institute for Astronomical Science Dezhou UniversityDezhou 253023China University of Chinese Academy of Sciences Beijing 100049China Hanvon Technology Co. LtdBeijing 100193China NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa

Radio frequency interference(RFI)is an important challenge in radio *** comes from various sources and increasingly impacts astronomical observation as telescopes become more *** this study,we propose a fast and effective method for removing RFI in pulsar *** use pseudo-inverse learning to train a single hidden layer auto-encoder(AE).We demonstrate that the AE can quickly learn the RFI signatures and then remove them from fast-sampled spectra,leaving real pulsar *** method has the advantage over traditional threshold-based filter method in that it does not completely remove contaminated channels,which could also contain useful astronomical information.

关键词： pulsars:general methods:numerical methods:data analysis

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Line profile studies of hydrodynamical models of cometary compact H II regions

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Research in Astronomy and Astrophysics 2015年第6期15卷 828-848页

作者： feng-Yao zhu Qing-feng zhu Department of Astronomy University of Science and Technology of China Key Laboratory for Research in Galaxies and Cosmology University of Science and Technology of China Chinese Academy of Sciences

We simulate the evolution of cometary H II regions based on several champagne flow models and bow shock models, and calculate the profiles of the [Ne II] fine-structure line at 12.81 μm, the H30α recombination line and the [Ne III] finestructure line at 15.55 μm for these models at different inclinations of 0°, 30° and 60°. We find that the profiles in the bow shock models are generally different from those in the champagne flow models, but the profiles in the bow shock models with lower stellar velocity （≤ 5 km s^-1） are similar to those in the champagne flow models. In champagne flow models, both the velocity of peak flux and the flux weighted central velocities of all three lines point outward from molecular clouds. In bow shock models, the directions of these velocities depend on the speed of stars. The central velocities of these lines are consistent with the stellar motion in the high stellar speed cases, but they are opposite directions from the stellar motion in the low speed cases. We notice that the line profiles from the slit along the symmetrical axis of the projected 2D image of these models are useful for distinguishing bow shock models from champagne flow models. It is also confirmed by the calculation that the flux weighted central velocity and the line luminosity of the [Ne III] line can be estimated from the [Ne II] line and the H30α line.

关键词： H II regions -- ISM kinematics and dynamics clusters -- line profiles

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Heating graphene to incandescence and the measurement of its work function by the thermionic emission method

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Nano Research 2014年第4期7卷 553-560页

作者： feng zhu State Key Laboratory of Low-Dimensional Quantum Physics Department of Physics and Tsinghua-Foxconn Nanotechnology Research Center Tsinghua University Beijing 100084 China Collaborative Innovation Center of Quanturn Matter Beijing 100084 China

The work function （WF） of graphene is an essential parameter in graphene electronics. We have derived the WF of graphene by the thermionic emission method. Chemical vapor deposition （CVD）-grown single-layered polycrystalline graphene on copper foil is transferred to a cross-stacked carbon nanotube （CNT） film drawn from a super-aligned multiwalled CNT array. By decreasing the pore size of the CNT film, the as-prepared CNT-graphene film （CGF） can be Joule heated to a temperature as high as 1,800 K in vacuum without obvious destruction in the graphene structure. By studying the thermionic emission, we derive the WF of graphene, ranging from 4.7 to 4.8 eV with the average value being 4.74 eV. Because the substrate influence can be minimized by virtue of the porous nature of the CNT film and the influence of adsorbents can be excluded due to the high temperature during the thermionic emission, the measured WF of graphene can be regarded as intrinsic.

关键词： graphene carbon nanotube thermionic emission work function

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Relation between microstructure and magnetic properties of shock wave-compressed Nd-Fe-B magnets

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Rare Metals 2022年第7期41卷 2353-2356页

作者： Ming-Gang zhu Yan-feng Li Wei Li Li-Yun Zheng Dong Zhou Hai-bo feng Lang Chen An Du Division of Functional Materials Central Iron and Steel Research InstituteBeijing 100081China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China College of Science Northeastern UniversityShenyang 110819China

The relationship between the microstructure and magnetic properties of Nd-Fe-B sintered magnet compressed by shock wave with 6.26 GPa≤p≤7.16 GPa was *** reveals that Nd-Fe-B magnets show a demagnetization behavior after compressed by shock *** intergranular fracture is the main occurring phe-nomenon in the shock wave-compressed *** coercivity of the shock wave-compressed Nd-Fe-B magnets could be recovered after repeating the annealing *** suggests that only the morphology change just like the intergranular fracture occurs,and there is no structural change in the grain boundary phase in the shock wave-compressed *** phase grain interconnection,microcracks and pores,and alterant orientation relationship between matrix phase and grain boundaries phase are con-sidered as induced factors of demagnetization.

关键词： Permanent magnets Coercivity Shock wave Demagnetization

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