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Phase behavior of rotationally asymmetric Brownian kites containing 90°internal angles

Chinese Physics B 2021年第12期30卷 467-472页

作者： Huaqing liu Yiwu Zong Zhanglin Hou Thomas G.mason Kun Zhao Key laboratory of Systems Bioengineering(Ministry of Education) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Wenzhou Institute University of Chinese Academy of SciencesWenzhou 325001China Department of Physics and Astronomy University of California-Los AngelesLos AngelesCA 90095USA Department of Chemistry and Biochemistry University of California-Los AngelesLos AngelesCA 90095USA Physics Department Tianjin UniversityTianjin 300072China

Previous Monte Carlo simulations have shown that ordered tetratic phases can emerge in a dense two-dimensional Brownian system of rotationally asymmetric hard kites having 90°internal ***,there have been no experimental investigations yet to compare with these simulation ***,we have fabricated two types of micron-sized kites having internal angles of 72°-90°-108°-90°and 72°-99°-90°-99°,respectively,and we have experimentally studied their phase behavior in two-dimensional *** and in contrast to the Monte Carlo simulations,the experimental results show a phase sequence of isotropic fluid-hexagonal rotator crystal-square crystal as the area fractionφA increases for both types of *** observed square crystal displays not only a quasi-long-range translational order but also(quasi-)long-range 4-fold bond-and molecular-orientational order;these characteristics confirm that tetratic order can emerge even in dense Brownian systems of rotationally asymmetric particles.A model based on local polymorphic configurations(lPCs)is proposed to understand the origin of the square lattice order in these dense kite *** results in this study provide a new route to realize custom-designed self-assembly of colloids by controlling lPCs.

关键词： tetratic order colloidal kites two-dimentional system phase behavior

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A New Method of Multi-Scale Geologic Modeling and Display

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Journal of Earth Science 2014年第3期25卷 537-543页

作者： Yongliang Bai Zhan liu lanfa liu Roger mason Binghu Huang School of Geosciences China University of Petroleum Earth Sciences Faculty China University of Geosciences Wuhan

A new method of multi-scale modeling and display of geologic data is introduced to provide information with appropriate detail levels for different types of research. The multi-scale display mode employs a model extending existing 2D methods into 3D space. Geologic models with different scales are organized by segmenting data into orthogonal blocks. A flow diagram illustrates an octree method for upscaling between blocks with different scales. Upscaling data from the smallest unit cells takes into account their average size and the Burgers vector when there are mismatches. A geocellular model of the Chengdao Reservoir of the Shengli Oilfield, China is taken as an illustrative case, showing that the methods proposed can construct a multi-scale geologic model correctly and display data from the multi-scale model effectively in 3D.

关键词： multi-scale geologic model block data organization topological relationship upscale geologic structure multi-scale display.

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Subterranean Origin of Accreted lapilli in Cone-Sheets of the Houshihushan Sub-Volcanic Ring Complex, Shanhaiguan, China

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Journal of Earth Science 2015年第5期26卷 661-668页

作者： Xia Wen Changqian Ma Roger mason longkang Sang Junming Zhao School of Nuclear Resources Engineering University of South China State Key laboratory of Geological Processes and Mineral Resources China University of Geosciences School of Earth Sciences China University of Geosciences

In addition to syenite ring dykes and multiple alkaline granite stocks, the sub-volcanic Houshihushan alkaline ring complex near Shanhaiguan, Qinhuangdao City, contains cone-sheets of two types： a majority filled with granite porphyry and a minority filled with quartz syenite porphyry. Many cone sheets show evidence of multiple magma intrusion events. Some granite porphyry sheets＇ multiple chilled margins display magmatic roll structures indicating that turbulent magma flowed up the fractures. In one upward-closing cone-sheet K-feldspar phenocrysts floated up through fluid granite porphyry magma and became concentrated at the top providing direct evidence of shallow-level crystal fractionation, confirmed by published rock analyses. Accreted lapilli with K-feldspar crystal cores occur only in the inner parts of a minority of cone-sheets and field relationships indicate that they must have formed beneath the ground surface. Similar lapilli occur in erupted ignimbrites preserved in the collapsed caldera. Voids between lapilli in cone-sheets indicate the presence of volumes of gas below the surface that could have flowed upwards as fast-moving hot gas streams. We propose a mechanism of formation that began with subterranean magmatic rolls with K-feldspar crystal cores that formed on dyke walls, and became detached. Then they were caught up in rising gas streams and erupted at the surface. Thus accreted lapilli formed underground, were erupted along with blobs of fluid glass in escaping gases, and transported over the surface in nuées ardentes, to settle and cool as ignimbrite flows.

关键词： accreted lapilli cone-sheets alkaline ring complex K-feldspar fractionation ignimbrite Houshihushan alkaline ring complex

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Effectiveness of quality physical education in improving students' manipulative skill competency

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Journal of Sport and Health Science 2016年第2期5卷 231-238页

作者： Weiyun Chen Weimo Zhu Steve mason Austin Hammond-Bennett andrew Colombo-Dougovito School of Kinesiology University of Michigan Kinesiology and Community Health University of Illinois Department of Kinesiology University of Virginia

Purpose： This study aimed to examine the extent to which the quality physical education teaching （QPET） practices contributed to improving 4th- and 5th-grade students＇ manipulative skill competency. Methods： Participants were 9 elementary physical education （PE） teachers and their 4th- and 5th-grade students （n = 2709 3420）. The students＇ skill competency was assessed with 3 manipulative skills using PE metrics assessment rubrics. The PE teachers＇ levels of QPET were assessed by coding 63 videotaped lessons using the assessing quality teaching rubrics （AQTR）, which consisted of 4 essential dimensions including task design, task presentation, class management, and instructional guidance. Codes were confirmed through inter-rater reliability （82.4%, 84.5%, and 94%）. Data were analyzed through descriptive statistics, multiple R2 regression models, and independent sample t tests. Results： This study indicated that the 4 essential dimensions of QPET were all significant contributors to students＇ manipulative skill competency. These predictors were significantly higher for boys than for girls in soccer and striking skills, while they were significantly higher for girls than for boys in throwing skill competency. Of the 4 essential dimensions of QPET, task presentation played the most significant role in contributing to all 3 skill competencies for both boys and girls. Further, students who experienced high QPET were significantly more skillfully competent than those students who did not have this experience. Conclusion： It was concluded that the QPET practices played a significantly critical role in contributing to students＇ manipulative skill competency.

关键词： Assessment of quality teaching Essential dimensions of teaching Manipulative skill competency Skill assessment

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Ediacaran Macrofossils in Shunyang Valley,Sixi,Three Gorges District,Hubei Province,China

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Journal of Earth Science 2017年第4期28卷 614-621页

作者： Roger mason Yuejie li Kenan Cao Yu long Zhen-Bing She School of Earth Sciences China University of GeosciencesWuhan 430074China State Key laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China

Previously undescribed Ediacaran macrofossils are documented in and close to a quarry southwest of Zigui in Shunyang Valley, near Sixi Village, Yangtze Three Gorges region, Hubei Prov- ince, China. Discoidal impressions, vendotaenids, and a new branching form occur in bedded carbon- ates through the entire 235 m thickness of the Dengying Formation. The quarry and nearby outcrops in the stream valley have significant potential for further discoveries of Ediacaran macrofossils.

关键词： Ediacaran macrofossil Dengying Formation Sixi.

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The evolution of coupling of Asian winter monsoon and high latitude climate of Northern Hemisphere——Grain evidence from 8.1 Ma loess-red clay sequence on the Chinese central loess Plateau

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Science China Earth Sciences 2001年第S1期44卷 185-191页

作者：吕连清方小敏 JosephA.mason 李吉均安芷生 MOE National laboratory of Western China’s Environmental Systems & Department of Geography Lanzhou University Lanzhou China State Key laboratory of loess and Quaternary Geology Institute of Earth Environment CAS Xi’an China Conservation and Survey Division and Department of Geosciences University of Nebraska-Lincoln Lincoln USA

The evolution and driving mechanism of the Asian winter monsoon system are of great importance to understanding the present-day climate. Through high-resolution particle size analysis of the oldest loess-red clay sequence known so far (with a basal age of about 8 Ma) and comparison of the results with oxygen isotope curves from North Atlantic marine sediments, 4 stages of the evolution of the Asian winter monsoon were clearly demonstrated. During the first stage, between about 8.1 and 4.3 Ma, there was no relation between Asian winter monsoon and Northern Hemisphere ice volume and high latitude climate inferred from marine sediments. A weak relation developed during the second stage, about 4.3 to 3.5 Ma. During the third stage (3.5 to 2.6 Ma) an Asian winter monsoon system similar to the present formed, initiating a stronger relation between the winter mcnsoon and Northern Hemisphere ice volume and high latitude climate. In the final stage (2.6 to 0 Ma) the present Asian winter monsoon system was fortified and stabilized and changes in the winter monsoon system were almost in phase with Northern Hemisphere ice volume and climate. The staggered uplift of Tibetan Plateau at ~8, 3.6, 2.6 Ma and later might be the driving force for the evolution of the Asian winter monsoon.

关键词： loess-red clay loess Plateau winter monsoon Tibetan Plateau.

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OPTIMIZATION OF A WAVE CANCEllATION MUlTIHUll SHIP USING CFD TOOlS

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Journal of Hydrodynamics 2002年第1期14卷 1-7页

作者： C. Yang, R. l■hner, O. Soto (School of Computational Sciences, George mason University Fairfax VA 22030-4444, USA) Sch. of Comp. Sci. George Mason Univ. Fairfax VA 22030-4444 United States

A simple CFD tool, coupled to a discrete surface representation and a gradient based optimization procedure, is applied to the design of optimal hull forms and optimal arrangement of hulls for a wave cancellation multihull ship. The CFD tool, which is used to estimate the wave drag, is based on the zeroth order slender ship approximation. The hu ll surface is represented by a triangulation, and almost every grid point on the surface can be used as a design variable. A smooth surface is obtained via a si mplified pseudo shell problem. The optimal design process consists of two steps . The optimal center and outer hull forms are determined independently in the fi rst step, where each hull forms are determined independently in the first step, where each hull keeps the same displacement as the original design while the wav e drag is minimized. The optimal outer hull arrangement is determined in the se cond step for the optimal center and outer hull forms obtained in the first step . Results indicate that the new design can achieve a large wave drag reduction i n comparison to the original design configuration.

关键词： hull form design hull form optimiza tion wave cancellation multihull ship trimaran wave resistance CFD tools sl ender ship approximation surface parameterization.

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Vertical stratification of ichneumonid wasp communities： the effects of forest structure and life-history traits

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Insect Science 2015年第5期22卷 688-699页

作者： Filippo Di Giovanni Pierfilippo Cerretti Franco mason Emma Minari lorenzo Marini Dipartimento di Biologia e Biotecnologie 'Charles Darwin' Universita di Roma 'La Sapienza' Piazzale A. Moro 5 00185 Rome Italy Centro Nazionale per lo Studio e la Conservazione della Biodiversita Forestale Corpo Forestale dello Stato via Carlo Ederle 161A 37100 Verona Italy and DAFNAE Universit& di Padova viale dell'Universita 16 35020 Legnaro Padua Italy

Parasitoid wasp communities of the canopy of temperate forests are still largely unexplored. Very little is known about the community composition ofparasitoids between canopy and understory and how much of this difference is related to forest structure or parasitoid biological strategies. In this study we investigated upon the difference in the community composition of the parasitic wasps Ichneumonidae between canopy and understory in a lowland temperate forest in northern Italy. We used general linear models to test whether parasitic strategy modifies species vertical stratification and the effect of forest structure. We also tested differences in β-diversity between canopy and understory traps and over time within single forest layers. We found that stand basal area was positively related to species richness, suggesting that the presence of mature trees can influence local wasp diversity, providing a higher number of microhabitats and hosts. The ichneumonid community of the canopy was different from that of the understory, and theβ-diversity analysis showed higher values for the canopy, due to a higher degree of species turnover between traps. In our analyses, the vertical stratification was different between groups of ichneumonids sharing different parasitic strategies. Idiobiont parasitoids of weakly or deeply concealed hosts were more diverse in the understory than in the canopy while parasitoids of spiders were equally distributed between the two layers. Even though the ichneumonid community was not particularly species-rich in the canopy of the temperate forests, the extension of sampling to that habitat significantly increased the number of species recorded.

关键词： β-diversity biological traits canopy forest structure Ichneumonidae vertical stratification

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Sand dunes as potential sources of dust in northern China

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Science China Earth Sciences 2016年第4期59卷 760-769页

作者： Mark R SWEENEY lU HuaYu CUI MengChun Joseph A mason FENG Han XU ZhiWei Department of Earth Sciences University of South Dakota laboratory of Earth Surface Process and Environment School of Geographic and Oceanographic Sciences Nanjing University Department of Geography University of Wisconsin-Madison

While saltation bombardment of sand grains on a fine substrate can produce considerable dust, the well-sorted nature of sand dunes tends to preclude them from consideration as major dust sources. Recent research, however, has revealed that sand dunes can, in some cases, be large sources of dust. We used the PI-SWERl(Portable In-Situ Wind Erosion laboratory) to measure in the field the potential of sand dunes and other desert landforms to emit particulate matter lan Buh, and Mu Us deserts of northern China. Combined with high resolution particle size measurements of the dune sand, an assessment of sand dunes as a dust source can be made. large active transverse dunes tend to contain little to no stored PM-10, yet they produce a low dust flux. Coppice dunes stabilized by vegetation contain appreciable PM-10 and have very high dust emission potential. There is a positive correlation between the amount of PM-10 stored in a dune and its potential dust flux. Saltation liberates loose fines stored in dunes, making them very efficient dust emitters compared to landforms such as dry lake beds and washes where dust particles are unavailable for aeolian transport due to protective crusts or sediment cohesion. In cases where large dunes do not store PM-10 yet emit dust when active, two hypotheses can be considered:(1) iron-oxide grain coatings are removed during saltation, creating dust, and(2) sand grains collide during saltation, abrading grains to create dust. Observations reveal that iron oxide coatings are present on some dune sands. PI-SWERl data suggests that low dust fluxes from dunes containing no stored dust may represent an estimate for the amount of PM-10 dust produced by removal of iron oxide coatings. These results are similar to results from dunes in the United States. In addition, PI-SWERl results suggest that dust-bearing coppice dunes, which cover vast areas of China's sandy deserts, may become major sources of dust in the f

关键词： Coppice dunes Transverse dunes Dust PI-SWERl Desert

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Simulation of Automatically Annotated Visible and Multi-/Hyperspectral Images Using the Helios 3D Plant and Radiative Transfer Modeling Framework

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Plant Phenomics 2024年第3期6卷 579-594页

作者： Tong lei Jan Graefe Ismael K.Mayanja mason Earles Brian N.Bailey Department of Plant Sciences University of CaliforniaDavisCAUSA leibniz Institute of Vegetable and Ornamental Crops e.V.(IGZ) GroßbeerenGermany Department of Biological and Agricultural Engineering University of CaliforniaDavisCAUSA Department of Viticulture and Enology University of CaliforniaDavisCAUSA

Deep learning and multimodal remote and proximal sensing are widely used for analyzing plant and crop traits,but many of these deep learning models are supervised and necessitate reference datasets with image *** these datasets often demands experiments that are both labor-intensive and ***,extracting traits from remote sensing data beyond simple geometric features remains a *** address these challenges,we proposed a radiative transfer modeling framework based on the Helios 3-dimensional(3D)plant modeling software designed for plant remote and proximal sensing image *** framework has the capability to simulate RGB,multi-/hyperspectral,thermal,and depth cameras,and produce associated plant images with fully resolved reference labels such as plant physical traits,leaf chemical concentrations,and leaf physiological *** offers a simulated environment that enables generation of 3D geometric models of plants and soil with random variation,and specification or simulation of their properties and *** approach differs from traditional computer graphics rendering by explicitly modeling radiation transfer physics,which provides a critical link to underlying plant biophysical *** indicate that the framework is capable of generating high-quality,labeled synthetic plant images under given lighting scenarios,which can lessen or remove the need for manually collected and annotated *** example applications are presented that demonstrate the feasibility of using the model to enable unsupervised learning by training deep learning models exclusively with simulated images and performing prediction tasks using real images.

关键词： framework simulation helios modeling plant annotated automatically hyperspectral images

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