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Randomly coupled trench-assisted multicore fibers with different arrangements for high tolerance of manufacturing errors

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Science China(Information Sciences) 2023年第11期66卷 260-272页

作者： Yongneng JIANG Jiajing TU Shecheng GAO weiping LIU Zhaohui LI Department of Electronic Engineering College of Information Science and Technology Jinan University School of Electronics and Information Technology Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems Sun Yat-sen University Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)

Randomly coupled multicore fibers(RC-MCFs) are promising candidates for long-haul transmission. However, the degree of coupling between the homogeneous cores of an RC-MCF is weakened if manufacturing errors appear. Therefore, a low-index trench layer is introduced into the coupled cores to investigate the effects of its position and thickness on the group index to enhance the tolerance of manufacturing errors. A depressed region is designed in the center of the core to solve the problem of the effective area decreasing because of the confinement of the low-index trench. Additionally, it is important to study the effective arrangement of the coupled cores to obtain a smaller group delay spread(GDS) within the limited 125-μm cladding; we discuss the single-layer and double-layer arrangements. A moderate range is found for both the bending radius and core pitch to minimize the GDS. For the single-layer arrangement, the degree of mixing is weak, and the degeneracy state does not easily change the bending conditions; thus, it may be a good candidate for designing systemically coupled multicore fibers. For the double-layer arrangement, the bending and twisting factors can induce sufficient mixing among the different modes to reduce GDS; thus,this arrangement is more suitable for the design of RC-MCFs.

关键词： manufacturing errors randomly coupled multicore fibers trench-assisted core single-layer arrangement double-layer arrangement

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Quantifying the short-term dynamics of soil organic carbon decomposition using a power function model

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Ecological Processes 2017年第1期6卷 100-108页

作者： weiping Zhou Jinhong He Dafeng Hui Weijun Shen Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory for Agro-Environment Ministry of AgricultureBeijing 100081China Key laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China university of Chinese Academy of Sciences Beijing 100049China Department of Biological Sciences Tennessee State UniversityNashvilleTN 37209USA.

Introduction:Soil heterotrophic respiration(Rh,an indicator of soil organic carbon decomposition)is an important carbon efflux of terrestrial ***,the dynamics of soil Rh and its empirical relations with climatic factors have not been well ***:We incubated soils of three subtropical forests at five temperatures(10,17,24,31,and 38°C)and five moistures(20,40,60,80,and 100%water holding capacity(WHC))over 90 *** was measured throughout the course of the *** types of models(log-linear,exponential,and power model)were fitted to the measurements and evaluated based on the coefficient of determination(r2)and Akaike Information Criterion(AIC)of the *** regression analysis was used to derive the empirical relations between model parameters and the two climatic ***:Among the three models,the power function model(Rh=R1 t−k)performed the best in fitting the descending trend of soil Rh with incubation time(r2>0.69 for 26 of 30 models).Both R1 and k generally increased linearly with soil temperature but varied quadratically with soil moisture in the three forest ***:This study demonstrated that the power function model was much more accurate than the exponential decay model in describing the decomposition dynamics of soil organic carbon(SOC)in mineral soils of subtropical *** empirical relations and parameter values derived from this incubation study may be incorporated into process-based ecosystem models to simulate Rh responses to climate changes.

关键词： Soil respiration Subtropical forest Moisture Temperature Power function Climate change

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免疫细胞及相关细胞因子在骨关节炎发病及治疗中的作用

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中国组织工程研究 2024年第2期28卷 280-287页

作者：孟志成乔卫平赵阳刘洪飞李凯杰马博河南中医药大学河南省郑州市450000 河南中医药大学第一附属医院骨伤科河南省郑州市450000

背景:骨关节炎的发生发展与免疫异常密切相关,各种免疫细胞、免疫介质在骨关节炎发病过程中的重要性不断被阐明。目的:综述免疫细胞及相关细胞因子在骨关节炎发病及治疗中的作用,为今后骨关节炎的研究和防治提供新的思路。方法:以“骨... 详细信息

背景:骨关节炎的发生发展与免疫异常密切相关,各种免疫细胞、免疫介质在骨关节炎发病过程中的重要性不断被阐明。目的:综述免疫细胞及相关细胞因子在骨关节炎发病及治疗中的作用,为今后骨关节炎的研究和防治提供新的思路。方法:以“骨关节炎,膝,巨噬细胞,T细胞,B细胞,自然杀伤细胞,树突状细胞,细胞因子,炎症因子,免疫细胞”“osteoarthritis,knee,macrophages,T cells,B cells,natural killer cells,dendritic cells,cytokines, inflammatory factors,immune cells”为检索词在中国知网、万方、维普和PubMed和Web of Science数据库中检索已发表的相关文献,阅读标题和摘要进行初筛,在阅读全文后,最后选取98篇文献进行综述。结果与结论:(1)既往研究认为骨关节炎发病与软骨磨损相关,近年来研究认为骨关节炎是免疫细胞广泛参与的一种慢性炎性状态,随着对骨关节炎发病机制的深入研究,学者们认为骨关节炎的发病机制是由早期先天免疫反应驱动的,这种免疫反应会逐步催化退行性变,最终导致关节微环境的改变。(2)各种免疫细胞和细胞因子是影响骨关节炎修复的关键因素,其中巨噬细胞、自然杀伤细胞参与滑膜炎症反应,T细胞免疫反应参与骨关节炎软骨的降解,并加重骨关节炎的病情。(3)免疫细胞分泌的白细胞介素1β、白细胞介素6、肿瘤坏死因子α、白细胞介素17和白细胞介素37等炎性细胞因子在骨关节炎的病理生理中发挥重要作用,其中白细胞介素1β是造成关节软骨破坏最重要的炎性因子。(4)在骨关节炎病早期阶段对免疫学危险因素进行评估,能够早期有效地进行治疗,可显著降低与骨关节炎相关的残疾、发病率和成本。(5)目前干细胞及其来源外泌体、生物材料进行免疫调节治疗骨关节炎的效果已在不同的实验模型中得到证实,但将其用于临床实践之前仍有大量的实验工作要做,随着新治疗靶点的发现,针对靶点进行相关治疗将为临床骨关节炎修复带来新的希望。

关键词：骨关节炎巨噬细胞 T细胞 B细胞自然杀伤细胞树突状细胞免疫细胞综述

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Transmission scheme and performance analysis for decode-and-forward MIMO two-way relay systems

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Science in China(Series F) 2009年第12期52卷 2308-2316页

作者： ZHAO Rui YANG LuXi ZHU weiping School of Information Science and Engineering Southeast University Nanjing 210096 China Department of Electrical and Computer Engineering Concordia University Montreal QC H3G 1M8 Canada

In rd （DF） MIMO two-way relay systems, the transmission schemes are designed and the closed-form expressions for the outage probability and average symbol error rate （ASER） of the twoway relay system are derived based on two different scenarios of channel state information （CSI）. For perfect CSI, the maximum-ratio-transmission and combining （MRT-MRC） technique is applied to design the beamforming and combining vectors. Without perfect CSI, the transmission scheme with limited feedback is designed, and the analytical results are verified through two kinds of codebooks, i.e., random vector quantization and Grassmann. The simulation results show that, the proposed transmission schemes for the two-way relay system can outperform other transmission schemes in the performance of outage probability and ASER, and the accuracy of the derived closed-form expressions is also verified by the numerical simulations.

关键词： decode-and-forward two-way relay outage probability average symbol error rate MRT-MRC limited feedback

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Photothermal materials for efficient solar powered steam generation

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Frontiers of Chemical Science and Engineering 2019年第4期13卷 636-653页

作者： Fenghua Liu Yijian Lai Binyuan Zhao Robert Bradley weiping Wu state Key Laboratory of Metal Matrix Composites School o f Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Materials University of OxfordOxfordOX13PHUK MatSurf Technology Ltd. CumbriaCA101NWUK Department of Electrical and Electronic Engineering School of MathematicsComputer Science and EngineeringCityUniversity of LondonNorthampton SquareLondonEC 1V OHBUK

Solar powered steam generation is an emerging area in the field o f energy harvest and sustainable *** nano-structured photothermal materials are able to harvest energy from the full solar spectrum and convert it to heat with high ***,the materials and structures for heat management as well as the mass transportation are also brought to the *** groups have reported their materials and structures as solutions for high performance devices,a few creatively coupled other physical fields with solar energy to achieve even better *** paper provides a systematic review on the recent developments in photothermal nanomaterial discovery,material selection,structural design and mass/heat management,as well as their applications in seawater desalination and fresh water production from waste water with free solar *** also discusses current technical challenges and likely future *** article will help to stimulate novel ideas and new designs for the photothermal materials,towards efficient,low cost practical solar-driven clean water production.

关键词： solar stream generation plasmonics porous carbon photothermal materials solar energy conversion efficiency water vapor generation rate

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Wastewater reclamation and reuse in China:Opportunities and challenges

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Journal of Environmental Sciences 2016年第1期28卷 86-96页

作者： Sidan Lyu weiping Chen Weiling Zhang Yupeng Fan Wentao Jiao state Key Laboratory for Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China university of Chinese Academy of Sciences Beijing 100049China

The growing water stress both in terms of water scarcity and quality deterioration promotes the development of reclaimed water as a new water resource use. This paper reviewed wastewater reuse practices in China, and the opportunities and challenges of expanding reclaimed water use were analyzed. Rapid urbanization with the increasing of water demand and wastewater discharge provides an opportunity for wastewater reuse. The vast amount of wastewater discharge and low reclaimed water production mean that wastewater reuse still has a great potential in China. Many environmental and economic benefits and successful reclamation technologies also provide opportunities for wastewater reuse. In addition, the overall strategy in China is also encouraging for wastewater reuse. In the beginning stage of wastewater reclamation and reuse, there are many significant challenges to expand wastewater reuse in China including slow pace in adopting urban wastewater reuse programs, the establishment of integrated water resources management framework and guidelines for wastewater reuse programs, incoherent water quality requirements, the limited commercial development of reclaimed water and the strengthening of public awareness and cooperation among stakeholders.

关键词： Wastewater reuse Urbanization Policy Integrated water resource management Public acceptance

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Late Triassic(Norian)Conodont Apparatuses Revealed by Conodont Clusters from Yunnan Province,Southwestern China

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Journal of Earth Science 2021年第3期32卷 709-724页

作者： weiping Zeng Mark A.Purnell Haishui Jiang Muhui Zhang state Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430078China School of Earth Sciences China University of GeosciencesWuhan 430074China Department of Geology University of LeicesterLeicester LEI 7RHUK

Almost all aspects of conodont research rely on a sound taxonomy based on comparative *** is founded on hypotheses of homology which ultimately rest on knowledge of the location of elements in the *** assemblages—fossils that preserve the articulated remains of the conodont skeletal apparatus—provide our only direct evidence for element location,but very few are known from the Late *** we describe fused clusters(natural assemblages)from the late Norian limestone beds of the Nanshuba Formation in Baoshan,Yunnan Province,southwestern *** arrangements and juxtaposition of S and M elements in multiple clusters reveal the composition of the apparatus of Mockina and,probably,*** indicate that these taxa had a standard 15 elements ozarkodinid apparatus,and provide new insights into the morphology of the elements occupying the P2,M and S locations of the *** apparatus comprised a single alate(hibbardelliform)S0 element,paired breviform digyrate(grodelliform)S1 and(enantiognathiform)S2 elements,paired bipennate(hindeodelliform)S3 and S4 elements,paired breviform digyrate(cypridodellifrom)M elements,paired,modified-angulate P2 elements(with reduced or lacking‘posterior’process)and segminiplanate(mockiniform and parvigondolelliform)P1 *** results will allow testing of the hypothesis that Mockina,Parvigondolella and Misikella—critical taxa in Late Triassic biostratigraphy—are closely related and possessed morphologically similar elements in homologous locations.

关键词： conodont apparatus Mockina Parvigondolella Misikella Triassic

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Model architecture-oriented combat system effectiveness simulation based on MDE

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Journal of Systems Engineering and Electronics 2017年第5期28卷 900-922页

作者： Yonglin Lei Ning Zhu Jian Yao Hessam Sarjoughian weiping Wang School of Information Systems and Management National University of Defense Technology School of Computing Informatics and Decision Systems Engineering Arizona State University

Combat system effectiveness simulation (CSES) is a special type of complex system simulation. Three non-functional requirements (NFRs), i.e. model composability, domain specific modeling, and model evolvability, are gaining higher priority from CSES users when evaluating different modeling methodologies for CSES. Traditional CSES modeling methodologies are either domain-neutral (lack of domain characteristics consideration and limited support for model composability) or domain-oriented (lack of openness and evolvability) and fall short of the three NFRs. Inspired by the concept of architecture in systems engineering and software engineering fields, we extend it into a concept of model architecture for complex simulation systems, and propose a model architecture-oriented modeling methodology in which the model architecture plays a central role in achieving the three NFRs. Various model-driven engineering (MDE) approaches and technologies, including simulation modeling platform (SMP), unified modeling language (UML), domain specific modeling (DSM), eclipse modeling framework (EMF), graphical modeling framework (GMF), and so forth, are applied where possible in representing the CSES model architecture and its components' behaviors from physical and cognitive domain aspects. A prototype CSES system, called weapon effectiveness simulation system (WESS), and a non-trivial air-combat simulation example are presented to demonstrate the methodology.

关键词： combat system effectiveness simulation (CSES) model architecture model-driven engineering (MDE) simulation modeling platform (SMP) domain specific modeling (DSM) weapon effectiveness simulation system (WESS)

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Microstructure and Mechanical Properties of a Wear-Resistant As-Cast Alloyed Bainite Ductile Iron

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Acta Metallurgica Sinica(English Letters) 2014年第3期27卷 476-482页

作者： Junjun Cui Hongyun Zhang Liqing Chen Haizhi Li weiping Tong state Key Laboratory of Rolling and Automation Northeastern University College of Mechanical and Vehicle Engineering Shenyang Institute of Technology Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern University

An as-cast bainite ductile iron with excellent mechanical properties and wear resistance was fabricated by alloying and centrifugal casting method, and the alloyed chemical composition was optimized by using the thermodynamic software Thermo-Calc. By using optical microscopy, transmission electron microscopy, scanning electron microscopy, and X-ray diffraction, the microstructure of the as-fabricated bainite ductile cast iron was characterized pertinent to the elements distribution in matrix and features of ferrite and retained austenite. The results of mechanical properties test show that the hardness and compressive strength of this alloyed ductile iron are 52 HRC and 2,200 MPa, respectively. The as- cast bainite ductile iron possesses highly abrasive wear resistance and the reason can be ascribed to the solid solution of the elements Si, Ni, Cu, and Mn in the austenite and the formation of carbides of elements Cr and Mo. The strength of bainite ductile iron is increased by the acicular bainitic ferrite in the matrix.

关键词： Bainite ductile iron Alloying Microstructure Abrasive wear resistance

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Multi-factors influencing the spatial distribution of polycyclic aromatic hydrocarbons in soils surrounding drinking water protection zone

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Journal of Environmental Sciences 2013年第8期25卷 1643-1648页

作者： Wentao Jiao Tieyu Wang Yonglong Lu Andrew Chang weiping Chen state Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Department of Environmental Sciences University of California

We selected the Guanting Reservoir in Beijing, China as a case where an industrial area locates on the upwind corner to study the influence of human activities and natural processes on the distribution of polycyclic aromatic hydrocarbons （PAHs） in soils. Soil PAH concentrations in the study area follow a log-normal probability distribution function, suggesting that distribution of PAH in soils was affected by human activities. Distribution of PAHs in soils was significantly affected by the point source that high PAH concentrations were observed in near industrial area with an obvious declining trend from the northwest to the southeast which was the prevailing wind direction in this area. Away from the influence of point source, distribution of PAHs in soils was found to significantly correlate with total organic carbon content, while the influences of agricultural land uses and type of soil texture on the total soil PAHs contents and ring compositions were quite limited. The results can provide some evidences and data on the pollutant accumulation in drink water protection area influenced by natural processes and human activities.

关键词： soil PAH contamination Guanting Reservoir PAH distribution

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