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On the time development of dispersion in electroosmotic flow througha rectangular channel

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Acta Mechanica Sinica 2012年第3期28卷 631-643页

作者： Suvadip paul Chiu-On Ng Department of Mechanical Engineering The University of Hong Kong

This is an analytical study on the time develop- ment of hydrodynamic dispersion of an inert species in elec- troosmotic flow through a rectangular channel. The objec- tive is to determine how the channel side walls may affect the dispersion coefficient at different instants of time. To this end, the generalized dispersion model, which is valid for short and long times, is employed in the present study. An- alytical expressions are derived for the convection and dis- persion coefficients as functions of time, the aspect ratio of the channel, and the Debye-Htickel parameter representing the thickness of the electric double layer. For transport in a channel of large aspect ratio, the dispersion may undergo several stages of transience. The initial, fast time develop- ment is controlled by molecular diffusion across the narrow channel height, while the later, slower time development is governed by diffusion across the wider channel breadth. For a sufficiently large aspect ratio, there can be an interlude between these two periods during which the coefficient is nearly steady, signifying the resemblance of the transport to that in a parallel-plate channel. Given a sufficiently long time, the dispersion coefficient will reach a fully-developed steady value that may be several times higher than that with- out the side wall effects. The time scales for these periods of transience are identified in this paper.

关键词： Taylor dispersion. Electroosmotic flow. Gener-alized dispersion model

DEM prediction of industrial and geophysical particle flows

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Particuology 2010年第2期8卷 106-118页

作者： paul W. Cleary CSIRO Mathematical and Information Sciences Private Bag 33 Clayton South 3169 Australia

Simulation of industrial particle flows using DEM （Discrete Element Method） offers the opportunity for better understanding of the flow dynamics by the inclusion of particle scale physics that often determine the nature of these flows. Increased understanding from the models can lead to improvements in equip- ment design and operation, potentially leading to large increases in equipment and process efficiency, throughput and]or product quality. Industrial applications are typically large and involve complex par- ticulate behaviour in complex geometries. This paper explores the critical influence of particle shape on granular system behaviour and then discusses examples of DEM applied to several large industrial problems. 2009 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. All rights reserved.

关键词： DEMGranular flowLandslideMillScreenMixing

Collaborative Assessments in Computer Science Education: A Survey

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Tsinghua Science and Technology 2019年第4期24卷 435-445页

作者： Hans Yuan paul Cao the Computer Science & Engineering Department University of CaliforniaSan Diego

As computer science enrollments continue to surge, assessments that involve student collaboration may play a more critical role in improving student learning. We provide a review on some of the most commonly adopted collaborative assessments in computer science, including pair programming, collaborative exams, and group projects. Existing research on these assessment formats is categorized and compared. We also discuss potential future research topics on the aforementioned collaborative assessment formats.

关键词： assessment collaboration pair programming collaborative exam group project

Unleashing the Power of Moiré Materials in Neuromorphic Computing

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Chinese Physics Letters 2023年第12期40卷 131-132页

作者： John paul Strachan Peter Grünberg Institute(PGI-14) Neuromorphic Compute NodesForschungszentrum JülichJülichGermany and RWTH Aachen UniversityAachenGermany

Reservoir computing has been an intriguing paradigm in the field of artificial intelligence and machine learning that draws inspiration from the complex dynamics of recurrent neural networks found in biological systems. Unlike traditional neural networks, reservoir computing separates the training of a fixed, randomly connected ‘reservoir’layer from a simpler ‘readout’ layer. This distinctive architecture allows the reservoir to process information in a highly dynamic and nonlinear manner.

关键词： networks neural computing

Impact of Land-use Patterns on Distributed Groundwater Recharge and Discharge——A Case Study of Western Jilin,China

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Chinese Geographical Science 2006年第3期16卷 229-235页

作者： Moiwo Juana paul College of Environment and Resources Jilin University

The impact of land-use on distributed groundwater recharge and discharge in the western Jilin (WJ) was analyzed in this study. WJ is a transitional, semi-arid zone with a fragile, hydrological closed ecosystem in the Songhua River Basin (SRB). The research tool includes a seamlessly linked MODFLOW, WetSpass, the Seepage packages, and ArcGIS. The model calibration showed good agreement between simulated water table elevation and measured water table depths, while predicted groundwater discharge zones showed strong correlations with field occurrences of drainage systems and wetlands. Simulated averages for distributed recharge, water table elevation and groundwater drawdown were 377.42mm/yr, 194.43m, and 0.18m respectively. Forest vegetation showed the highest recharge, followed by ag- ricultural farmlands, while open-water and other drainage systems constituted groundwater exit zones. When present land-use conditions were compared with the hypothetical natural pre-development scenario, an overall loss of ground- water recharge (24.09mm/yr) was observed, which for the project area is 18.05×108m3. Groundwater abstraction seemed to be the cause of water table drawdown, especially in the immediate vicinities of the supply wells. An important issue of the findings was the ability of the hypothetical forest vegetation to protect, and hence sustain aquifer reserves and dependent ecosystems. The profound data capture capability of ArcGIS makes it particularly useful in spa- tio-temporal hydroecological modeling.

关键词： land-use ecosystem groundwater recharge discharge Western Jilin

Distinct expression profiles of transcriptional coactivators for thyroid hormone receptors during Xenopus laevis metamorphosis

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Cell Research 2003年第6期13卷 459-464页

作者： BINDU D paul National Institutes of Health Laboratory of Gene Regulation and Development National Institute of Child Health and Human Development Bldg. USA.

The biological effects of thyroid hormone (T3) are mediated by the thyroid hormone receptor (TR). Amphibian metamorphosis is one of the most dramatic processes that are dependent on T3. T3 regulates a series of orchestrated developmental changes, which ultimately result in the conversion of an aquatic herbivorous tadpole to a terrestrial carnivorous frog. T3 is presumed to bind to TRs, which in turn recruit coactivators, leading to gene activation. The best-studied coactivators belong to the p160 or SRC family. Members of this family include SRC1/ NCoA-1, SRC2/TIF2/GRIP1, and SRC3/pCIP/ACTR/AIB-l/RAC-3/TRAM-1. These SRCs interact directly with liganded TR and function as adapter molecules to recruit other coactivators such as p300/CBP. Here, we studied the expression patterns of these coactivators during various stages of development. Amongst the coactivators cloned in Xenopus laevis, SRC3 was found to be dramatically upregulated during natural and T3-induced metamorphosis, and SRC2 and p300 are express

关键词： transcription coactivators thyroid hormone receptor Xenopus laevis metamorphosis histone acetylation.

Climatic significance of δ^(18)O records from an 80.36 m ice core in the East Rongbuk Glacier, Mount Qomolangma (Everest)

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Science China Earth Sciences 2005年第2期48卷 266-272页

作者： paul A. Mayewski Climate Change Institute University of Maine OronoME 04469USA

The δ18O variations in an 80.36 m ice core retrieved in the accumulation zone of the East Rongbuk Glacier, Mount Qomolangma (Everest), is not consistent with changes of air temperature from both southern and northern slopes of Himalayas, as well as these of the temperature anomalies over the Northern Hemisphere. The negative relationship between the δ18O and the net accumulation records of the ice core suggests the "amount effect" of summer precipitation on the δ18O values in the region. Therefore, the δ18O records of the East Rongbuk ice core should be a proxy of Indian Summer Monsoon intensity, which shows lower δ18O values during strong monsoon phases and higher values during weak phases.

关键词： East Rongbuk ice core δ18O values air temperature Indian Summer Monsoon.

Deforestation and forest fragmentation in the highlands of Eastern Ghats,India

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Journal of Forestry Research 2021年第3期32卷 1127-1138页

作者： Rakesh paul Kakoli Banerjee Central University of Orissa KoraputOdishaIndia

Tropical forest cover change along with increasing fragmentation has detrimental effects on the global *** the current study change in both forest cover and fragmentation of Koraput district have been assessed in the past three decades(1987-2017)and future decade(2017-2027),which has been modelled using logistic regression showing a gradual decrease in the forest cover and increase in *** long term deforestation rates from 1987 to 2017(current period)and from 1987 to 2027(predicted period)were found to be-0.018 and-0.012,*** of the total geographical area,2027 number of grids(1 km^(2))out of 8856 grids were found to have shown extinction of forest in the study *** conversion of forested lands into other land uses has been one of the major causes of deforestation in Koraput,especially because of the increasing mining activities and establishment of three major industries namely National Aluminium Company(NALCO),Damanjodi,Hindustan Aeronautics Limited(HAL),Sunabeda and Ballarpur Industries Limited(BILT).The forest fragmentation reveals a negative trend,recording highest conversion from large core fragments to edge(191.33 km2)and the predicted period has also shown the same trend of negative change,which poses serious danger to the structure of the *** of all the landscape matrices calculated,number of patches will increase to 214 in 2027 from 93 in *** the test between geographically weighted regression(GWR)and ordinary least square regression(OLS),GWR was the better fit model for drawing a spatial relationship between forest cover and fragmentation *** study confirmed that the forest cover change has impacted the forest fragmentation in the study *** programmes like REDD+should be implemented along with the experiences of Community Forest Management and the joint forest management should be intensified at community level in order to develop better management practices to conserve habitats in biodi

关键词： Forest cover Forest ecosystem Predictive model Forest fragmentation Grid based change Geographically weighted regression

Enhanced Trust Based Access Control for Multi-Cloud Environment

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Computers, Materials & Continua 2021年第12期69卷 3079-3093页

作者： N.R.Rejin paul D.paul Raj Technology PuduvoyalGummidipoondi601206India R M D Engineering College KavaraipettaiGummidipoondi601206India

Security is an essential part of the cloud *** ensuring the security of the data being communicated to and from the cloud server,a significant parameter called trust was ***-based security played a vital role in ensuring that the communication between cloud users and service providers remained unadulterated and *** most cloud-based data distribution environments,emphasis is placed on accepting trusted client users’requests,but the cloud servers’integrity is seldom *** paper designs a trust-based access control model based on user and server characteristics in a multi-cloud environment to address this *** proposed methodology consists of data encryption using Cyclic Shift Transposition Algorithm and trust-based access control *** this trust-based access control mechanism framework,trust values are assigned to cloud users using direct trust *** direct trust degree is estimated based on the following metrics:success and failure rate of interactions,service satisfaction index,and dishonesty *** addition to this,trust values are assigned to cloud servers based on the metrics:server load,service rejection rate,and service access *** role-Based Access control policy of each user is modified based on his trust *** the server fails to meet the minimum trust level,then another suitable server will be *** proposed system is found to outperform other existing systems in a multi-cloud environment.

关键词： Cloud computing trust access control cloud service provider cloud data user CSTA