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Understanding Governance Structures in Shaping Greenway Implementation in City-Regions: A Case Study in Central Zhejiang Province, China
Greenway implementation in city-regions is a collective action involving a complex range of relations between regional and local agencies, between government departments at the same administrative level, and between adjacent jurisdictions. This paper explores how greenway implementation governance is structured, and why different governance structures result in different greenway implementation processes and outcomes in a city-region. We use a case study approach to a greenway project in central Zhejiang Province (CCCZ), where data are collected through field reconnaissance, in-depth interviews, and document analysis. Preliminary findings reveal that the central Zhejiang Greenway Project has experienced a development from ‘territorially-specialized governance’ to ‘cross-scale governance’. ‘Double-hatted’ agencies comprising government leaders and professional representatives from different agencies can create cross-scale institutional linkages both vertically (across levels of governments) and horizontally (across jurisdictions an
The contributions of components to the axial charges of proton and its resonances
We calculate the axial charges of the proton and its resonances in the
framework of the constituent quark model, which is extended to include the
components. If 20% admixtures of the components in
the proton are assumed, the theoretical value for the axial charge in our model
is in good agreement with the empirical value, which can not be well reproduced
in the traditional constituent quark model even though the symmetry breaking or relativistic effect is taken into account. We also
predict an unity axial charge for with 30%
components constrained by the strong and electromagnetic decays.Comment: 4 pages, 4 table
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Sedimentation of the Lower Cretaceous Xiagou formation and Its Response to Regional Tectonics in the Qingxi Sag, Jiuquan Basin, NW China
Under the constraint of an isochronous sequence stratigraphic framework, sediment infill of the Xiagou Formation reflects the overall control of dynamic tectonic movements and episodic sedimentations in the Qingxi Sag. Structure reactivity during post-depositional processes could cause stratigraphic variations in longitudinal time and lateral space. This study documents sediment infill features and their response to the tectonic evolutions of the Qingxi Sag. The data sets include comparison of cores, well drilling, 3D seismic, inter-well correlation, wave impedance inversion profiles, original strata recovery data, sedimentary fades spatial evolution and their superimposition with paleogeomorphology. The Jiuquan Basin is a Mesozoic-Cenozoic superposition basin comprising an early rifting graben phase and a later compression phase. Since the Early Cretaceous, the basin has undergone four major tectonic episodes: 1) extension during the Early Cretaceous, 2) tectonic inversion caused by northwest-southeast contraction from the Late Cretaceous to the Paleocene, 3) weak extension from the Eocene to the Miocene and 4) contraction from the Miocene to the present. Therefore, the Jiuquan Basin is the product of taphrogenic, collisional and shearing movements. Seismic interpretations of sequence and maximum flooding surface divide the Xiagou Formation into three third order sequences: SQK1g(0), SQK1g(1) and SQK1g(2+3). Five sedimentary facies associations are identified: the shoreland plain, fan delta dominated sedimentary systems, turbidite deposits, shallow lakes and half-deep lake systems. From K1g(0) to K1g(2+3), decreased sandstone percentages in three fan delta areas indicate a continuously transgressive process, which shows the transition from proximal to distal sites in most statistic wells and an obvious decrease of fan delta scales. The northeast-southwest faults control the lakeward distributions of delta fronts and turbidite fans. The correspondence of sedimentary infill and its response to tectonic movements have been demonstrated in the Qingxi Sag. The more active eastern part of the northeastern boundary fault has an important influence on the northeastward migration of depocenters in the Xiagou Formation. The topography developed continuously from K1g(0) to K1g(2+3), but the diminished subsidence indicates the dominant geological process varying from intense fault rifting in an early period to relatively gentle and overall subsidence in a later period during the Early Cretaceous. (C) 2013 Elsevier Ltd. All rights reserved.Key Laboratory of Tectonics and Petroleum Resources, Ministry of Education TPR-2011-09Project of "Double strong effect, driving mechanism and hydrocarbon significance of tectonic activity during depositional period of Dongying Formation in Qikou and Nanpu Sag, Eastern China" 41272122Geological Science
Improved mechanical and electrical properties in electrospun polyimide/multiwalled carbon nanotubes nanofibrous composites
Highly aligned polyimide (PI) and PI/multi-walled carbon nanotubes (PI/MWCNTs) nanofibrous composites by incorporating poly(ethylene oxide) as the dispersing medium were fabricated using electrospinning technique. The morphology, mechanical, and electrical properties of the electrospun nanofibrous composites were investigated. Scanning electron microscope showed that the functionalized MWCNTs (f-MWCNTs) were well dispersed and oriented along the nanofiber axis. Analysis of electrical properties indicated a remarkable improvement on the alternating current conductivity by introduction of the aligned f-MWCNTs. Besides, with addition of 3 vol.% f-MWCNTs, the obvious enhancement of tensile modulus and strength was achieved. Thus, the electrospun PI/MWCNTs nanofibrous composites have great potential applications in multifunctional engineering materials
Quantum Control in Open and Periodically Driven Systems
Quantum technology resorts to efficient utilization of quantum resources to
realize technique innovation. The systems are controlled such that their states
follow the desired manners to realize different quantum protocols. However, the
decoherence caused by the system-environment interactions causes the states
deviating from the desired manners. How to protect quantum resources under the
coexistence of active control and passive decoherence is of significance.
Recent studies have revealed that the decoherence is determined by the feature
of the system-environment energy spectrum: Accompanying the formation of bound
states in the energy spectrum, the decoherence can be suppressed. It supplies a
guideline to control decoherence. Such idea can be generalized to systems under
periodic driving. By virtue of manipulating Floquet bound states in the
quasienergy spectrum, coherent control via periodic driving dubbed as Floquet
engineering has become a versatile tool not only in controlling decoherence,
but also in artificially synthesizing exotic topological phases. We will review
the progress on quantum control in open and periodically driven systems.
Special attention will be paid to the distinguished role played by the bound
states and their controllability via periodic driving in suppressing
decoherence and generating novel topological phases.Comment: A review articl
Improved PSO algorithm based on chaos theory and its application to design flood hydrograph
AbstractThe deficiencies of basic particle swarm optimization (bPSO) are its ubiquitous prematurity and its inability to seek the global optimal solution when optimizing complex high-dimensional functions. To overcome such deficiencies, the chaos-PSO (COSPSO) algorithm was established by introducing the chaos optimization mechanism and a global particle stagnation-disturbance strategy into bPSO. In the improved algorithm, chaotic movement was adopted for the particles' initial movement trajectories to replace the former stochastic movement, and the chaos factor was used to guide the particles' path. When the global particles were stagnant, the disturbance strategy was used to keep the particles in motion. Five benchmark optimizations were introduced to test COSPSO, and they proved that COSPSO can remarkably improve efficiency in optimizing complex functions. Finally, a case study of COSPSO in calculating design flood hydrographs demonstrated the applicability of the improved algorithm
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