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Petrology and geochemistry of clastic sedimentary rocks as evidences for provenance of the Late Palaeozoic Madzaringwe Formation, Tshipise-Pafuri Basin, South Africa

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Science China Earth Sciences 2016年第12期59卷 2411-2426页

作者： Ntokozo MALAZA LIU KuiWu ZHAO BaoJin Department of Geology University of Fort Hare Worley parsons South Africa

Petrography and geochemistry(major, trace and rare earth elements) of clastic rocks from the Late Palaeozoic Madzaringwe Formation, in the Tshipise-Pafuri Basin, Northern South Africa, have been investigated to understand their provenance. Sandstone petrography and detrital modes indicates that the Late Palaeozoic succession was derived from craton interior and recycled orogen provenance. Sandstones in the Madzaringwe Formation are sub-arkosic to sub-litharenite. The sediments may represent a recycled to craton interior provenance. The geochemical data of major elements show that sandstone and shales have the same source. The study of paleoweathering conditions based on modal composition, chemical index of alteration(CIA) and A-CN-K(Al2O3-Ca O+Na2O-K2O) relationships indicate that probably chemical weathering in the source area and recycling processes have been more important in shale and sandstone rocks. The relatively high CIA values(70–90%) indicates moderate to high weathering conditions of the samples and the paleoclimate of the source area was warm. K2O/Na2 O versus Si O2 and Na2O-Ca O-K2 O tectonic setting discrimination plots, suggest a passive continental margin. In the study of trace elements, triangular Th-Sc-Zr/10 and La-Th-Sc plots both suggest a passive margin setting of the basin. Petrographic and geochemical results of the samples suggest uplifted basement source areas dominated by sedimentary rocks and/or granite-gneiss rocks. The source rocks might have been the recycled pre-Soutpansberg Karoo Supergroup rocks and the metasedimentary rocks of the Soutpansberg Group. Other source rocks may have been the pre-Beit-Bridge basement rocks(granites and gneisses).

关键词： Tshipise-Pafuri Basin Karoo Supergroup Sediment petrography Geochemistry Provenance Tectonic setting

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

Subsidence Analysis and Burial History of the Late Carboniferous to Early Jurassic Soutpansberg Basin,Limpopo Province,South Africa

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Acta Geologica Sinica(English Edition) 2016年第6期90卷 2000-2007页

作者： Ntokozo MALAZA LIU Ken ZHAO Baojin Department of Geology University of Fort Hare Worley parsons 39 Melrose BoulevardMelrose Arch

The subsidence history of the Soutpansberg Basin was reconstructed by a tectonic subsidence analysis coupled with backstripping calculations based on data of newly interpreted sequence boundaries. Furthermore, burial and time plots were constructed in order to understand the burial and thermal history of the basin. Input data were based on facies, lithostratigraphic models and tectonic interpretations. The studied succession is up to 1000 m and is underlain by the Achaean Limpopo Mobile Belt. The subsidence within the basin supports the primary graben system which must have been centred within the present basins, and later became a region of faulting. The subsidence and burial history curves suggests two phases of rapid subsidence during the Early-Late Permian （300–230 Ma） and Middle Triassic （215–230 Ma）. The areas of greater extension subsided more rapidly during these intervals. Two slow subsidence phases are observed during the Late Triassic （215–198 Ma） and Early Jurassic （198–100 Ma）. These intervals represent the post-rift thermal subsidence and are interpreted as slow flexural subsidence. Based on these observations on the subsidence curves, it is possible to infer that the first stage of positive inflexion （300 Ma） is therefore recognised as the first stage of the Soutpansberg Basin formation.

关键词： Basin subsidence Karoo Supergroup Soutpansberg basin Permian-Jurassic

Intersecting disciplinary frameworks:the architecture and ecology of the city

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Ecosystem Health and Sustainability 2018年第6期4卷 2-13页

作者： Brian McGrath Department of Architecture Parsons School of DesignThe New SchoolNew YorkNYUSA.

Introduction:While many studies have explored the link between ecology and urban design,this paper examines two major conceptions that can promote deeper connections between architecture and ecological ***:Rather than providing a comprehensive review,the paper explores in detail two frameworks that have not yet been exploited as foundations for a bridge between these *** is the seminal work of Aldo Rossi on the architecture of the city,as opposed to a more traditional architectural focus on specific buildings,lots,or specific *** com-plementary fr amework for ecological science is the ecology of the city,developed to support and explain a new era of more integrated social-ecological study of urban systems than had existed ***:This paper draws heretofore unexamined parallels between architecture as represented by the work of Rossi and the ecology of the city as represented by the Baltimore School of Urban *** ecology of the city has become a widely used framing in the science of urban ecology,while the architecture of the city continues to influence a deeper understanding of the built environment as a *** parallels provided by the architecture of the city and the ecology of the city help to understand the historical interrelations between nature and ***:Intersecting the two conceptual frameworks of the architecture and ecology of the city can help satisfy the call for an actionable ecology for the *** call demands both disciplines integrate their conceptual frameworks with communities in the collective enter-prise of creating urban ecosystem health,justice,and sustainability.

关键词： Architecture ecology urban design urban artifacts patch dynamics

Benefits for the bunker industry in adopting blockchain technology for dispute resolution

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Blockchain(Research and Applications) 2023年第2期4卷 101-112页

作者： Daniel Adam Dante Benjamin Matellini Anna Kaparaki Liverpool John Moores University James Parsons BuildingByrom StreetLiverpool L33AFUK

he bunker industry has faced negative perception to their trust and credibility in recent *** is further compounded by the need for the industry to answer new challenges to meet the requirement of the International Maritime Organization *** aim of this work is to illustrate how blockchain technology may be adopted for aiding in bunker dispute *** demonstrate how blockchain may aid in disputes within the bunker industry,this paper first examines the existing bunker supply process,which involves the formation of contracts under English law,the Bunker Delivery Notes,the different types of disputes that may arise during a bunker transaction and the methods of dispute resolution utilised by the ***,the current literature in relation to blockchain technology and blockchain smart contracts is ***,interviews and surveys within the industry have been conducted to identify the benefits and challenges in adopting blockchain *** research found that blockchains may benefit the bunker supply chain offering the effective resolution of bunker quality ***,blockchains may also serve as a verification tool for electronic bunker delivery notes,which may aid quality and quantity bunker disputes as well as compliance with the new International Maritime Organisation 2020 *** a result,despite the research having shown blockchain to be situationally dependent and having an element of legal uncertainty,blockchain does offer a solution to aid in bunker disputes and for improving the trust and credibility within the bunker industry.

关键词： Bunker industry Bunker supply contracts Dispute resolution Blockchain smart contracts Electronic bunker delivery notes

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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浅埋软土隧道稳定性极限分析

土木工程学报 1998年第5期31卷 62-72页

作者：姜功良 parsons Brinckerhoff

稳定性分析在浅埋软土隧道工程设计中占有重要位置.本文应用极限分析理论的上限原理及有限元法求解隧道的稳定系数,明显改善了既有的上限分析结果,并且同下限分析结果很接近,因此可以更好地界定准确解的范围.此外,有限元优化的机动可容... 详细信息

稳定性分析在浅埋软土隧道工程设计中占有重要位置.本文应用极限分析理论的上限原理及有限元法求解隧道的稳定系数,明显改善了既有的上限分析结果,并且同下限分析结果很接近,因此可以更好地界定准确解的范围.此外,有限元优化的机动可容许破坏速度场有助于理解浅埋软土隧道的破坏机制.本文所用的有限元极限分析方法也适用于研究其他土体结构的总体稳定性.

关键词：软土隧道稳定系数上限原理有限元极限分析

Strengthening behavior of AlCoCrFeNi(TiN)_(x) high-entropy alloy coatings fabricated by plasma spraying and laser remelting

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Journal of Materials Science & Technology 2022年第26期121卷 163-173页

作者： Bingqian Jin Nannan Zhang Shuo Yin Department of Material Science and Engineering Shenyang University of TechnologyShenyang 110870China Department of Mechanical Manufacturing and Biomedical EngineeringTrinity College DublinThe University of DublinParsons BuildingDublin 2Ireland

High-entropy alloy(HEA)coatings are of great importance in the fabrication of wear resistance *** coatings containing ceramic particles as reinforcement phase usually have better wear *** this study,AlCoCrFe Ni(TiN)_(x)(x:molar ratio;x=0,0.2,0.4,0.6,0.8,1.0)HEA coatings were fabricated on Q235 steel by plasma spray first and then subjected to laser *** experimental results confirm that plasma spray together with post laser remelting could result in the in-situ formation of TiN-Al_(2)O_(3) ceramic particles and cuboidal B2 phase in the AlCoCrFeNi(TiN)_(x) HEA *** in-situ TiN-Al_(2)O_(3) and nano-cuboidal B2 precipitation phase strengthened the coatings and improved their wearresistance *** to the dispersion of hard phase and nano-particles resulting from second heating,the microhardness of the Al Co Cr Fe Ni(Ti N)coatings significantly increased from 493 to 851 HV after laser *** the same reasons,the wear-resistance performance was also significantly promoted after laser remelting.

关键词： High-entropy alloy Coatings Ceramics Laser remelting Microstructure Wear resistance

Traffic control devices for deterring wrong-way driving： Historical evolution and current practice

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Journal of Traffic and Transportation Engineering(English Edition) 2017年第3期4卷 280-289页

作者： Fatemeh Baratian-Ghorghi Huaguo Zhou parsons Corporation Atlanta CA 30092 USA Department of Civil Engineering Auburn University Auburn AL 36849 USA

Each year, hundreds of fatal wrong-way driving （WWD） crashes occur across the United States. Thousands of injuries are reported in crashes caused by wrong-way drivers. Traffic control devices （TCDs）, i.e., signs, pavement markings, and signals, have been introduced since 1935 to combat this problem. The aim of the paper is to provide a complete history of TCDs for deterring WWD on freeways and divided highways in previous versions of the Manual on Uniform Traffic Control Devices （MUTCD）（1935-2009）. A fully referenced overview of definitions, text passages, and figures of the TCDs, employed to deter WWD in all MUTCD versions, will be given to characterize the changes over time. In addition, the efforts that have been made by state department of transportation （DOT） especially over the past few years to aggressively attack WWD by deploying standard TCDs are reviewed. Finally, the paper makes conclusions and recommendations with regard to the necessity of a revision in the next edition of MUTCD for WWD TCDs. The investigation of changes and the current practice leave a trail to enable traffic engineers and policy makers to consider past decisions and their effectiveness in combating WWD, as well as providing a reference to determine whether or not their jurisdiction meets the MUTCD standards.

关键词： Wrong-way driving Traffic control devices Sign Pavement marking Green arrow signal