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A copula-based approach to accommodate intra-household interaction in workers' daily maintenance activity stop generation modeling

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第1期9卷 59-68页

作者： you-lian chu Parsons Transportation Group New YorkNY 10005USA

A new stop frequency model was developed to predict the daily number of maintenance activity stops made by individual household heads during a typical weekday. This new model was based on the modification of a conventional multivariate ordered probit(MOP) model by maintaining the probit assumption for the marginal distributions while introducing nonnormal dependence among the error terms using copula functions. Therefore, the copulabased MOP model would relieve the restriction of imposing joint normality on the error terms in the conventional MOP model. The new MOP model would not only account for the intrahousehold interactions in stop-making decisions, but also allow the best functional form to be determined for representing dependencies among household heads. Using the New York Metropolitan Transportation Council’s 2010/2011 regional household travel survey data, the copula-based MOP model was employed to examine stop-making behavior for individual household heads residing in New York City and its adjacent counties in Mid-Hudson Valley and New Jersey. Empirical results provided useful insights into the observed effects of sociodemographics, land use density, transportation service, and work schedule together with potential unobserved common effects on the inter-relatedness of spousal stop-making decisions at the household level. The results show that the MOP model with a Clayton copula structure provides the best data fits and there is a very strong positive dependence among error terms of stop-making equations. Furthermore, the dependence among the maintenance activity propensities of household heads is asymmetric, with a stronger tendency of household heads to simultaneously have low maintenance activity levels than to simultaneously have high maintenance activity levels.

关键词： Stop-making propensity Maintenance activity episodes Multivariate ordered probit model Copula-based approach Intra-household interaction

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Implementation of a new network equilibrium model of travel choices

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Journal of Traffic and Transportation Engineering(English Edition) 2018年第2期5卷 105-115页

作者： you-lian chu Parsons Transportation Group Inc. New York NY 20005 USA

This paper develops a new combined network equilibrium model by using more behaviorally sound mathematical forms to represent the four travel choices（i.e., trip frequency,destination, mode, and route） in a conventional travel demand forecasting process. Trip frequency choice relates to the traveler decision on “making a trip” or “not making a trip”so it is given by a binary logit model. Destination choice is formulated as a parameterized dogit model of which the captivity parameters（expressed as functions of independent variables） allow individual travelers to be captive to specific destinations. Mode choice is given by a two-level nested logit model to avoid IIA restriction. Trip assignment is based on Wardrop＇s “user-optimized” principle. All model forms describing travel choices are in response to the level of services incurred by the transportation system. Through the introduction of inclusive values, the traveler decisions concerning trip frequency, destination, mode, and route choices are inherently interrelated and jointly *** obtain solutions of the new combined model, it was reformulated as an equivalent convex programming problem with linear constraints, a great advantage from the computational aspects. The model was applied empirically to a transportation network in New Jersey. The application results show that the new model is consistently better than the commonly used logit combined model in reproducing the observed trip flows from origin zones, origin to destination（O-D） trip flows, O-D trip flows by mode, and trip flows on the network links.

关键词： Combined model Parameterized dogit model Nested loot model Wardrop's user equilibrium Equivalent minimization problem

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Validation of an improved two-fluid model with particle rotation for gas-solid fluidized bed

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Particuology 2023年第10期81卷 149-161页

作者： lian Wang Xihua chu School of Civil Engineering Wuhan UniversityWuhan430072HubeiChina

Gas-solid fluidized beds are widely applied in chemical and process *** is of significance to establish a reasonable and effective mathematical model to explore the hydrodynamics of gas-particle system for industrial *** a less computationally demanding alternative to the discrete descriptions,two-fluid model considering kinetic theory of granular flow is often adopted to describe the fluidized behaviors of particles,but it cannot characterize the rotation of particles and its influence on the fluidized *** this study,to address the rotation effect of the fluidized particles,a two-fluid model combining the classical fluid and micropolar fluid is established,namely *** the CMTFM,classical fluid is used to describe the motion of gas phase,while micropolar fluid is adopted to describe the motion of particle phase,and the rotation of particles and its influence on the hydrodynamics of the gas-particle system are characterized by the degree of freedom of microrotation and the improved drag force based on micropolar *** the calculation of the gas-solid bubbling fluidized bed,we investigated the influence of the microstructure parameters,particle-particle collision restitution coefficient and inlet velocity,and the results are compared to those from TFM model and *** the analysis,it manifests that pressure drop and expansion height of the fluidized bed under the consideration of the microrotation effect are closer to the experiments,which demonstrates the feasibility and advantage of the classical-micropolar two-fluid model.

关键词： Gas-solid fluidized bed Two-fluid model Micropolar fluid Microstructure parameter Fluidized behaviors

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Identification and characterization of adult alpha-and beta-globin genes and their genomic arrangement in Pseudosciaena crocea

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Acta Oceanologica Sinica 2006年第4期25卷 65-76页

作者： chu Wuying QIAN Ronghua WANG lianshen YU Xiameng you Zhenqiang YU lian Department of Biomedical Engineering Zhejiang University Hangzhou 310027 China Institute of Preventive Veterinary Medicine Zhejiang University Hangzhou 310029 China

The α- and β-globin genes from Pseudosciaena crocea were cloned by rapid amplification of cDNA 3 ＇-end （ 3 ＇-RACE）. The cDNA of the α-globin is 595 bp with the ATG start codon located at Position 37, the TAA stop codon at Position 469 and the AATAAA polyadenylation signal at Position 560, which codifies 145 amino acids. The entire open reading frame of the β-globin gene is 447 bp long, which encodes 148 amino acids. Amino acid identity of the α- globin or β-globin gene compared with those reported in other fish species, ranged from 31.9% to 76.4%. When comparing with human α- and β-globins, three important alterations in the structural regions can be noted： ct39 Thr→Gln, α113 His→Tyr and β117 His→Lys. The α-globin has a unique inserted amino acid residue in the 47th position. To understand the process of globin gene duplication and identify the regulatory elements present in the intergenic and intragenic regions of globin genes, the genomic arrangement of α- and β-globin genes was investigated. The results showed that the orientation of the two genes was head-to-head relative to each other. The intergenic region between the translation initiation codons of the linked α- and β-globin genes contains classical promoter elements and the length of it is much shorter than that reported in other fish.

关键词： Pseudosciaena crocea globin gene cloning structural region head-to-head regulatory elements

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Transformation of astragalosides from Radix Astragali under acidic,neutral,and alkaline extraction conditions monitored by LC-ESI-TOF/MS

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Chinese Journal of Natural Medicines 2014年第4期12卷 314-320页

作者： chu chu LIU E-Hu QI lian-Wen LI Ping State Key Laboratory of Natural Medicines China Pharmaceutical University

AIM: To reveal the profile of astragalosides for better quality evaluation of Radix Astragali, this study was aimed to investigate the transformation of astragalosides under different conditions. METHOD: Seven major astragalosides were selected for evaluation under acidic, neutral and alkaline conditions. The transformation in real plant samples was also examined and the products were characterized by LC-ESI-TOF/MS. RESULTS: In weak acidic solution, all of the astragalosides are stable. In addition, the transformation ratios of the astragalosides under neutral and alkaline conditions were also obtained. CONCLUSION: In neutral solution, malonylastragaloside I was transformed to astragaloside I; and in alkaline solution, substituent group(s) in the xylose moiety of all the astragalosides were eliminated. Since astragalosdie IV is the basic skeleton structure of the astrgalosides, it is a common transformation product of other astragalosides.

关键词： Transformation Radix Astragali LC-TOF/MS Astragalosides

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Paleoproterozoic granitic gneisses of the Dinggye and LhagoiKangri areas from the higher and northern Himalaya,Tibet:Geochronology and implications

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Science China Earth Sciences 2008年第2期51卷 240-248页

作者： LIAO QunAn LI DeWei LU lian YUAN YieMing chu LingLin Faculty of Earth Sciences China University of GeosciencesWuhan 430074China

Granitic gneisses have been widely found in crystalline rocks in the Dinggye area of the Higher Himalaya (HHM) and the LhagoiKangri area of the North Himalaya (NHM), Tibet. In the HHM, the gneisses intruded in the granulite-amphibolite facies metamorphosed sedimentary rocks, known as Nyalam group. In the NHM, the gneisses intruded in the amphibolite facies metamorphosed ones, known as LhagoiKangri group. These granitic gneisses are peraluminous monzonitic granites in terms of their mineral assemblage, and are considered as being derived from metamorphosed sedimentary rocks by anatexis based on the transitional relationship of the gneisses with their migmatitized wall rocks. Zircons are similar in crystal shape and interior structure from both gneisses. Most of them are euhedral or subhedral elongated prism-shaped transparent crystals, with fine oscillatory zoning, showing the magmatic genesis. Some of them are short prism-shaped and with relict core inherited from magma source and oscillatory zoning mantle crystallized from magma. SHRIMP U-Pb dating of zicons shows that both the granitic gneisses in the HHM and NHM are Paleoproterozoic (1811.6±2.9 Ma and 1811.7±7.2 Ma, respectively). These ages are similar to those (1815 to 2120 Ma) from granitic gneiss which is widely distributed in the Lesser Himalaya (LHM). The ages of inherited zircons (>2493.9±7.0 Ma, 2095.8± 8.8 Ma, 1874±29 Ma) exhibit the possible presence of several thermal events in Paleoproterozoic. All of the ages suggest the same India basement beneath the different units in Himalaya area, and do not support the idea that the HHM and NHM are accretionary terranes in Pan-Africa orogenic event. The fact that the basement in HHM is as old as or even younger than LHM is inconsistent with the presently prevalent orogenic models such as either extrusion of low-viscosity mid-crust or orogenic channel.

关键词： Higher Himalaya Paleoproterozoic granitic gneiss Indian basement geochronology

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Cooling and Crack Suppression of Bone Material Drilling Based on Microtextured Bit Modeled on Dung Beetle

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Chinese Journal of Mechanical Engineering 2023年第2期36卷 116-128页

作者： Yunsong lian Xiande Chen Chaoping Xie Yangyang Long Fengtian Lin Wei Zhou Xuyang chu Department of Mechanical and Electrical Engineering Xiamen UniversityXiamen 361102China Institute of Dynamics and Vibration Research Leibniz Universitat Hannover30167 HannoverGermany Xiamen Golden Egret Special Alloy Co. LtdXiamen 361100China

In recent years,the number of patients with orthopedic diseases such as cervical spondylosis has increased,resulting in an increase in the demand for orthopedic ***,thermal necrosis and bone cracks caused by surgery severely restrict the development and progression of orthopedic *** the material of cutting tool processing bone in bone surgery of drilling high temperature lead to cell death,easy to produce the problem such as crack cause secondary damage effects to restore,in this paper,a bionic drill was designed based on the micro-structure of the dung beetle's head and *** microstructure configuration parameters were optimized by numerical analysis,and making use of the optical fiber laser marking machine preparation of bionic bit;through drilling test,the mathematical model of drilling temperature and crack generation based on micro-structure characteristic parameters was established by infrared thermal imaging technology and acoustic emission signal technology,and the cooling mechanism and crack suppression strategy were *** experimental results show that when the speed is 60 m/min,the cooling effects of the bionic bit T1 and T2 are 15.31%and 19.78%,respectively,and both kinds of bits show obvious crack suppression *** research in this paper provides a new idea for precision and efficient machining of bone materials,and the research results will help to improve the design and manufacturing technology and theoretical research level in the field of bone drilling tools.

关键词： Bionic drill Bone material cutting Laser processing Thermal imaging camera Acoustic emission

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A 2-D FINITE ELEMENT MODEL SIMULATION OF THE MELTING PROCESS OF Al-Ti ALLOY IN VACUUM INDUCTION FURNACE WITH COLD CRUCIBLE(VIFCC)

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Acta Metallurgica Sinica(English Letters) 2004年第3期17卷 229-237页

作者： S.C.chu S.S.lian F.K.Chen Institute of Materials Science and Engineering National Taiwan UniversityTaibei(Taipei)Institute of Materials Science and EngineeringNational Taiwan UniversityTaibei(Taipei)Institute of Mechanical EngineeringNational Taiwan UniversityTaibei(Taipei)

The development of a numerical model for the melting process of Al--Ti alloy targetmaterial in vacuum induction furnace with cold crucible (VIFCC)was described. It isa two--dimensional computational methodology to calculate electromagnetic field, heattransfer field and fluid flow field. Based on the aid of the finite element method withthe commercial software--ANSYS, a superimposition method of a layer of copper anda slit to simulate the VIFCC melting process was used. The method was effectiveto save large quantity of memory and computing time. Meanwhile, a temperaturedistribution profile during the melting process was obtained. Validity of the model wasconfirmed by comparison between the result from calculation and those from directmeasurement by optical pyrometer and indirect investigation by ingot macrostructure.A relatively good agreement was found. Further, a nearly directional solidificationstrvcture was obtained under properly controlling the cooling rate and heating power.Therefore, such model developed in this article is feasible.

关键词： VIFCC ANSYS superimposition ingot macrostructure

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Synthesis, characterization, and anti-cancer activity of emodin-Mn(Ⅱ) metal complex

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Chinese Journal of Natural Medicines 2014年第12期12卷 937-942页

作者： YANG Li TAN Jun WANG Bo-chu ZHU lian-Cai Key Laboratory of Biorheological Science and Technology (Chongqing University) Ministry of Education College of Bioengineering Chongqing University School of Biological & Chemical Engineering Chongqing University of Education

To synthesize and characterize a novel metal complex of Mn(II) with emodin, and evaluate its anti-cancer activity. The elemental analyses, IR, UV-vis, atomic absorption spectroscopy, TG-DSC, 1H NMR, and 13 C NMR data were used to characterize the structure of the complex. The cytotoxicity of the complex against the human cancer cell lines HepG 2, HeL a, MCF-7, B16, and MDA-MB-231 was tested by the MTT assay and flow cytometry. Emodin was coordinated with Mn(II) through the 9-C=O and 1-OH, and the general formula of the complex was Mn(II)(emodin)2·2H2O. In studies of the cytotoxicity, the complex exhibited significant activity, and the IC50 values of the complex against five cancer cell lines improved approximately three-fold compared with those of emodin. The complex could induce cell morphological changes, decrease the percentage of viability, and induce G0/G1 phase arrest and apoptosis in cancer cells. The coordination of emodin with Mn(II) can improve its anticancer activity, and the complex Mn(II)(emodin)2·2H2O could be studied further as a promising anticancer drug.

关键词： Emodin Cytotoxicity Metal complex Cell cycle arrest Apoptosis

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Effects of retrorsine on mouse hepatocyte proliferation after liver injury

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World Journal of Gastroenterology 2006年第9期12卷 1439-1442页

作者： Xiao-Fei Zhou Qian wang Jian-xin chu Ai-lian Liu Centerfor Developmental Biology Xinhua Hospital Shanghai JiaotongUniversity School of Medicine Shanghai 200092 China

AIM： To study the effect of retrorsine on mouse hepatocyte proliferation. METHODS： Mice and rats were treated respectively with two injections of retrorsine （as retrosine-treated group） or saline （as non-treated group） at 2 wk intervals. They received a single injection of carbon tetrachloride （CCh） 4 wk later. On d 0, 1, 2, 3, 4, 6, 15 after CCh administration, the animals were killed and their livers were excised. Hematoxylin and eosin （HE） staining and Ki-67 antibody immunohistochemical analysis of liver samples were used to evaluate the pathological changes and hepatocyte proliferation. RESULTS： In rats treated with retrorsine and CCl4, the liver displayed obvious megalocytosis, proliferation of mild bile duct, small hepatocyte-forming nodule, which were not found in liver samples from non-treated group. However, in mice treated with retrorsine combined with CCh, the liver displayed hepatocyte degeneration and necrosis in perivenous areas. There was no obvious difference between retrorsine-treated group and nontreated group. Ki-67 immunohistochemical analysis showed that in rats treated with retrorsine, the positive hepatocytes mainly found in small hepatocyte nodules, were obviously less than those in non-treated group. The mice treated with retrorsine showed that the number of Ki-67 positive hepatocytes was very high and more than that in non-treated group. CONCLUSION： Retrorsine has no effect on mouse hepatocyte proliferation.

关键词： Retrorsine House Rat Hepatocyte proliferation

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