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China Communications 2023年第11期20卷 131-141页

作者： Ran Liu daniel N.Aloi School of Engineering and Computer Science Oakland UniversityRochester HillsMI-48309USA

Vehicle-to-Everything(V2X) communications will be an essential part of the technology in future autonomous drive decision systems.A fundamental procedure is to establish a robust communication channel between end-to-end *** to the antenna placed at different positions on vehicles,the existing cellular electro-magnetic(EM) wave propagation modelling does not fit properly for V2X direct communication *** order to figure out a feasible understanding of this problem,this paper focuses on the propagation channel analysis in a rural Vehicle-to-Vehicle(V2V) scenario for vehicular communication with antenna position experiments at different *** adopting the ray-tracing algorithm,a rural scenario simulation model is built up via the use of a commercial-off-the-shelf(COTS) EM modelling software package,that computes the path loss received power and delay spread for a given propagation ***,a real-world vehicle measurement campaign was performed to verify the simulation *** simulated and measured receiver power was in good agreement with each other,and the results of this study considered two antenna types located at three different relative heights between the two *** research provides constructive guidance for the V2V antenna characteristics,antenna placement and vehicle communication channel analysis.

关键词： antenna simulation and measurement propagation channel modeling ray-tracing simula-tion V2V scenario propagation

Understanding Hydrogen Redistribution During Steel Casting,and Its Effective Extraction by Thermally Induced Up-Hill Diffusion

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Journal of Iron and Steel Research International 2011年第S1期18卷 159-163页

作者： Gaude-fugarolas daniel Independent Research and Consultancy in Physical Metallurgy and Engineering c/.Alcalde Joan Batalla 408340 Vilassar de MarSpain

The severe loss of ductility caused by hydrogen in high strength steels has been the object of intense research during *** of the high mobility of hydrogen once has entered the metal,even in comparison with other interstitial atoms like carbon and nitrogen,a rigorous description of hydrogen fluxes during manufacturing of steel components is considered to be essential.A physical model of interstitial element diffusion is used to study the fluxes of hydrogen during solidification and cooling of cast *** particular,the present model contemplates diffusion in its most comprehensive description,i.e.,atom diffusion is driven by a reduction of the Gibbs energy of the ***,it is only considered the case in which diffusion occurs to reduce the concentration gradient of an element at constant matrix composition and ***,in a more general view,and as was proven by Darken (1949),diffusion may occur even up-hill the composition gradient as long it still leads to a reduction of Gibbs energy in the *** diffusion occurs due to a temperature gradient,it has been referred to as thermal diffusion or Ludwig-Soret *** model presented incorporates physical description of thermal agitation and atom mobility of interstitial elements,the influence of temperature gradients,solubility and saturation of the interstitial elements as function of temperature and matrix phases,as well as the kinetics of degassing at high *** application of this model shows how hydrogen localizes in some regions of the component to a degree that depends on manufacturing conditions and where it may reach concentrations well beyond the initial average concentration in the *** model describes as well how the FCC to BCC phase transformation may drive hydrogen concentration beyond supersaturation,due to the disparate capability of these phases to dissolve *** the other hand,this study has also enabled the development of a method for the

关键词： hydrogen diffusion embrittlement extraction

A Principal Component Analysis(PCA)-based framework for automated variable selection in geodemographic classification

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Geo-Spatial Information Science 2019年第4期22卷 251-264,I0003页

作者： Yunzhe Liu Alex Singleton daniel Arribas-Bel Geographic Data Science Lab Department of Geography and PlanningUniversity of LiverpoolLiverpoolUK

A geodemographic classification aims to describe the most salient characteristics of a small area zonal ***,such representations are influenced by the methodological choices made during their *** particular debate are the choice and specification of input variables,with the objective of identifying inputs that add value but also aim for model *** this context,our paper introduces a principal component analysis(PCA)-based automated variable selection methodology that has the objective of identifying candidate inputs to a geodemographic classification from a collection of *** proposed methodology is exemplified in the context of variables from the UK 2011 Census,and its output compared to the Office for National Statistics 2011 Output Area Classification(2011 OAC).Through the implementation of the proposed methodology,the quality of the cluster assignment was improved relative to 2011 OAC,manifested by a lower total withincluster sum of square *** the UK,more than 70.2%of the Output Areas(OAs)occupied by the newly created classification(***-OAC)outperform the 2011 OAC,with particularly strong performance within Scotland and Wales.

关键词： Geodemographics variable selection UK census spatial data mining principal component analysis

ADDRESSING EQUITY ISSUE IN MULTI-ACTOR POLICYMAKING VIA A SYSTEM-OF-SYSTEMS APPROACH:AVIATION EMISSIONS REDUCTION CASE STUDY

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Journal of Systems Science and Systems Engineering 2011年第1期20卷 1-24页

作者： D.Buyung AGUSDINATA daniel A.DELAURENTIS System-of-Systems Laboratory(SoSL) College of EngineeringPurdue University School of Aeronautics and Astronautics Purdue University

Finding equitable policy solutions is critical for developing sustainable energy *** paper presents a system-of-systems(SoS) formalism for addressing the equity issue in multi-actor *** a SoS,the control of the overall system performance is shared among a network of *** contrast to a single optimal solution that aggregates objectives of actors,the solution concept of iso-performance is formulated and employed to illuminate multiple solutions and hence the ’space’ for actors to *** specifically accounting for the equity issue,the level of sacrifice each actor makes for each iso-performance solution is *** demonstrate the approach,a case study is presented about policymaking to reduce fuel life cycle aviation emissions in the United States based on the year 2020 reduction target,involving government,airlines,jet fuel refinery companies,and aircraft and engine manufacturers.A resource allocation mixed integer programming model is employed to calculate carbon emissions resulting from airlines’ deployment of aircraft fleet to meet changing air transport *** paper discusses three iso-performance solutions;each of them requires a different level of sacrifice from each *** an insight can inform policymaking in determining the magnitude of compensation required when a particular solution is pursued.

关键词： System-of-systems equity multi-actor policymaking iso-performance solutions aviation emissions.

Electronic Absorption Spectroscopy of H2X （X=O, Te, Po）： Theoretical Treatment of Spin-Orbit Effects

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Chinese Journal of Chemical Physics 2009年第2期22卷 171-177页

作者： Chérif A. A. Ndoye Chantal daniel Laboratoire de Chimie Quantique Institut de Chimie UMR 7177 CNRS-Université de Strasbourg 4 Rue Blaise Pascal 67000 Strasbourg France

The electronic spectroscopy of H2X （X=O, Te, Po） was investigated by means of spinorbit configuration interaction （EPCISO） and restricted active space state interaction （SORASSI）. The transition energies to the low-lying singlet and triplet states of H2O, in which the SO interaction is zero, compare rather well with the experimental data as well as to other theoretical values. The theoretical electronic absorption spectrum is characterized by three allowed transitions A^1B1 （2px（O）→σ^＊g/3s（O））, B^1A1（σg→σ^＊g/3s（O）） and A^1S2（σg→σ^＊u） calculated at 7.68, 9.94, and 11.72 eV, respectively. The theoretical absorption spectra of H2X （X=Te, Po） are shifted to the red with the A^1B1 （npx（X）→σ^＊g） states calculated at 5.06 eV （H2Te） and 4.40 eV （H2Po） and the A^1B2 （σg→σ^＊u） states calculated at 7.89 eV （H2Te） and 7.77 eV （H2Po）. The largest SO splitting amounts to 0.34 eV and is found for the lowest a^3A1 of H2Po. In H2Te the SO effects are still negligible with a maximum splitting of 0.04 eV for the lowest a^3B2. The two methods lead to comparable results but the EPCISO approach depends strongly on the reference wavefunction.

关键词： Spin-orbit Excited state Group Ⅵ dihydride

A methodology for simulating 2D shock-induced dynamic stall at flight test-based fluctuating freestream

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Chinese Journal of Aeronautics 2019年第10期32卷 2223-2238页

作者： Khider AL-JABURI daniel FESZTY Fred NITZSCHE Department of Mechanical and Aerospace Engineering Carleton University

A comprehensive methodology for simulating 2 D dynamic stall at fluctuating freestream is proposed in this paper.2 D CFD simulation of a SC1095 airfoil exposed to a fluctuating freestream of Mach number 0.537±0.205 and Reynolds number 6.1×10~6(based on the mean Mach number)and undergoing a 10°±10°pitch oscillation with a frequency of 4.25 Hz was *** conditions were selected to be representative of the flow experienced by a helicopter rotor airfoil section in a real-life fast forward *** constant freestream dynamic stall as well as fluctuating freestream dynamic stall simulations were conducted and *** methodology was carefully validated with experimental data for both transonic flow and dynamic stall under fluctuating ***,the results suggest that the fluctuating freestream alters the dynamic stall mechanism documented for constant freestream in a major way,emphasizing that inclusion of this effect in the prediction of dynamic stall related rotor loads is imperative for rotor performance analysis and blades design.

关键词： Mach fluctuation Pitching airfoil Shock-induced dynamic stall Transonic flow Unsteady freestream velocity

Nanomechanical hydrodynamic force sensing using suspended microfluidic channels

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Microsystems & Nanoengineering 2023年第3期9卷 95-102页

作者： Alberto Martín-Pérez daniel Ramos Optomechanics Lab Instituto de Ciencia de Materiales de Madrid(ICMMCSIC)3 Sor Juana Inés de la Cruz(Madrid)E-28049 MadridSpain

Microfluidics has demonstrated high versatility in the analysis of in-flow particles and can even achieve mechanical properties measurements of biological cells by applying hydrodynamic ***,there is currently no available technique that enables the direct measurement and tracking of these hydrodynamic forces acting on a flowing *** this work,we introduce a novel method for the direct measurement of the hydrodynamic force actuating on an in-flow particle based on the analysis of the induced resonance changes of suspended microchannel resonators(SMRs).This hydrodynamic force sensitivity depends on the device used;therefore,we considered the geometry and materials to advance this dependency on the SMR resonance frequency.

关键词： hydrodynamic applying flow

Efects of solution chemistry on arsenic(V) removal by low-cost adsorbents

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Journal of Environmental Sciences 2013年第11期25卷 2291-2298页

作者： Yuru Wang daniel C.W.Tsang Department of Civil and Environmental Engineering Hong Kong Polytechnic University Department of Civil and Natural Resources Engineering University of Canterbury

Natural and anthropogenic arsenic （As） contamination of water sources pose serious health concerns, especially for small communities in rural areas. This study assessed the applicability of three industrial byproducts （coal fly ash, lignite, and green waste compost） as the low-cost adsorbents for As（V） removal under various field-relevant conditions （dissolved oxygen, As（V）/Fe ratio, solution pH, and presence of competing species）. The physico-chemical properties of the adsorbents were characterized by XRD, XRF, FT-IR, and NMR analysis. Batch experiments demonstrated that coal fly ash could provide effective As（V） removal （82.1%-95%） because it contained high content of amorphous iron/aluminium hydroxides for As（V） adsorption and dissolvable calcium minerals for calcium arsenate precipitation. However, the addition of lignite and green waste compost was found unfavourable since they hindered the As（V） removal by 10%-42% possibly due to dissolution of organic matter and ternary arsenate-iron-organic matter complexes. On the other hand, higher concentrations of dissolved iron （comparing As（V）/Fe ratios of 1：1 and 1：10） and dissolved oxygen （comparing 0.2 and 6 mg/L） only marginally enhanced the As（V） removal at pH 6 and 8. Thus, addition of dissolved iron, water aeration, or pH adjustment became unnecessary because coal fly ash was able to provide effective As（V） removal under the natural range of geochemical conditions. Moreover, the presence of low levels of background competing （0.8 or 8 mg/L of humic acid, phosphate, and silicate） imposed little influence on As（V） removal, possibly because the high adsorption capacity of coal fly ash was far from exhaustion. These results suggested that coal fly ash was a potentially promising adsorbent that warranted further investigation.

关键词： adsorption arsenic coal fly ash green waste compost lignite

Does reproductive mode affect sexually-selected coloration?Evaluating UV-blue spots in parthenogenetic and bisexual lizards of the genus Darevskia

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Current Zoology 2021年第2期67卷 201-213页

作者： Andran ABRAMJAN Marine ARAKELYAN daniel FRYNTA Department of Zoology Faculty of ScienceCharles UniversityVinicná7Prague12843Czech Republic Depatment of Zoology Faculty of BiologyYerevan State UniversityAlek Manoogian 1Yerevan0025Armenia

Sexual selection often leads to evolution of conspicuous signals,raising the chances of attracting not only potential mates,but also *** lacertid lizards,ultraviolet(UV)-blue spots on flanks and shoulders represent such a *** level of correlation between male and female ornamen-tation is also known to ***,the phenotype of females may change in the absence of sexual *** tested this hypothesis on a complex of parthenogenetic and bisexual lizards of the genus *** evaluated area,counts,and chromatic properties(UV opponency,sat-uration)of UV-blue spots and compared the values between the clones and their bisexual progeni-tor *** found a fair heterogeneity between the parthenogenetic species,but no general tendency toward higher crypsis or *** of the parthenogens were not signifi-cantly different from the values of sexual females.A possible explanation is that the changes in se-lective forces associated with parthenogenetic reproduction are too small to affect the resulting pattern of selective pressures on the studied traits,or that the phenotypes of the parthenogens re-sult from the unique combination of parental genomes and are conserved by clonal reproduction.

关键词： clonal reproduction coloration reptiles sexual selection visual modeling

Hypoxia inducible factor in hepatocellular carcinoma:A therapeutic target

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World Journal of Gastroenterology 2015年第42期21卷 12171-12178页

作者： daniel Lin Jennifer Wu Fellow Hematology and Medical Oncology Program NYU School of Medicine Perlmutter Cancer Center NYU Langone Medical Center Division of Hematology and Oncology NYU School of Medicine Subdivision of GI Oncology Perlmutter Cancer Center NYU Langone Medical Center Division of Hematology and Oncology

Hepatocellular carcinoma(HCC) is one of the most commonly diagnosed and deadly cancers worldwide; its incidence has been rising in the United States due to the increase in hepatitis C associated cirrhosis and the growing epidemic of obesity. There have been no effective therapeutic options in the advanced disease setting beyond sorafenib, a multi-targeted tyrosine kinase inhibitor that showed significant survival benefit. Because of this, there is an urgent need to search for novel pathways in sorafenib experienced patients. This review will focus on the role of hypoxia and hypoxiainducible factor alpha(HIF-1α) in cancer development, specifically in HCC. We will discuss the biology of HIF-1α, the pathways with which it interacts, and the function of HIF-1α in HCC. Furthermore, we will review studies highlighting the relevance of HIF-1α in the clinical setting, as well as the pre-clinical data supporting its further investigation. Finally, we will conclude with a discussion of the potential role of a HIF-1α m RNA antagonist for the treatment of HCC, and hypothesize the ways in which such an inhibitor may be best utilized in the management of advanced HCC. Hypoxia plays a significant role in the development of HCC. HIF-1α is a key transcription factor involved in the hypoxic response of cancer cells. It activates transcription of genes responsible for angiogenesis, glucose metabolism, proliferation, invasion and metastasis in HCC. Its involvement in multiple, essential tumor pathways makes it an attractive potential therapeutic target in HCC.

关键词： Hypoxia Hypoxia-inducible factor alpha Hepatocellu