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An Improved Data-Driven Topology Optimization Method Using Feature Pyramid networks with Physical Constraints

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Computer Modeling in Engineering & Sciences 2021年第9期128卷 823-848页

作者： Jiaxiang Luo Yu Li Weien Zhou ZhiqiangGong Zeyu Zhang Wen Yao College of Aerospace Science and Engineering National University of Defense TechnologyChangsha410073China National Innovation Institute of Defense Technology Chinese Academy of Military ScienceBeijing100000China

Deep learning for topology optimization has been extensively studied to reduce the cost of calculation in recent ***,the loss function of the above method is mainly based on pixel-wise errors from the image perspective,which cannot embed the physical knowledge of topology ***,this paper presents an improved deep learning model to alleviate the above difficulty *** feature pyramid network(FPN),a kind of deep learning model,is trained to learn the inherent physical law of topology optimization itself,of which the loss function is composed of pixel-wise errors and physical *** the calculation of physical constraints requires finite element analysis(FEA)with high calculating costs,the strategy of adjusting the time when physical constraints are added is proposed to achieve the balance between the training cost and the training ***,two classical topology optimization problems are investigated to verify the effectiveness of the proposed *** results show that the developed model using a small number of samples can quickly obtain the optimization structure without any iteration,which has not only high pixel-wise accuracy but also good physical performance.

关键词： Topology optimization deep learning feature pyramid networks finite element analysis physical constraints

Rapid earthquake focal mechanism inversion using high-rate GPS velometers in sparse network

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Science China Earth Sciences 2015年第11期58卷 1970-1981,1页

作者： GUO AiZhi NI SiDao CHEN WeiWen Jeffrey T.FREYMUELLER SHEN ZhiChao State Key Laboratory of Geodesy and Earth's Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences School of Earth and Space Sciences University of Science and Technology of China Geophysical Institute University of Alaska Fairbanks

In this study, we demonstrate an approach for inverting earthquake source parameters based on high-rate global positioning system （GPS） velocity seismograms. The velocity records obtained from single-station GPS velocity solutions with broadcast ephemeris are used directly for earthquake source parameter inversion using the Cut and Paste method, without requiring conversion of the velocity records into displacement records. Taking the E1 Mayor-Cucapah earthquake as an example, GPS velocity records from 10 stations with reasonable azimuthal coverage provide earthquake source parameters very close to those from the Global centroid moment tensor （Global CMT） solution. In sparse network tests, robust source parameters with acceptable bias can be achieved with as few as three stations. When the number of stations is reduced to two, the bias in rake angle becomes appreciable, but the magnitude and strike estimations are still robust. The results of this study demonstrate that rapid and reliable estimation of earthquake source parameters can be obtained from GPS velocity data. These parameters could be used for early earthquake warning and shake map construction, because such GPS velocity records can be obtained in real time.

关键词： high-rate GPS velometer GPS velocity determination CAP method earthquake source parameters sparse network

Comprehensive Evaluation of the Suitability of Agricultural Land in Myanmar

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Journal of Resources and Ecology 2018年第6期9卷 609-621页

作者： GU Changjun ZHANG Yili LIU Linshan LI Lanhui ZHANG Binghua Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of chinese Academy of Sciences Beijing 100049China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China

Myanmar is a country with an economy based on *** has rich agricultural resources and great potential for *** development of agriculture in Myanmar is becoming increasingly important to international food *** of agricultural land resources in Myanmar are the basis for the country's agricultural development and for food security *** this paper we used the MaxEnt model to analyze the relationship between the suitability of land for agricultural reclamation and the main environmental variables in Myanmar,and then constructed a model to comprehensively evaluate the suitability of land for agriculture in *** results show that:1)the overall accuracy of the MaxEnt model is high (AUC>0.8),which means there is a high correlation between the database of selected environmental indicators and the true distribution of cultivated land in Myanmar.2)Soil depth is the most important factor affecting the suitability of land for agriculture in Myanmar When the thickness of soil layer is less than 100 cm,the suitability of land for agriculture is *** respect to topographic conditions,slope is the main factor affecting *** the slope is greater than 20 degrees,the suitability of land for agriculture is *** respect to climate conditions,precipitation is the main influencing factor. There is a positive correlation between river network density and land suitability.3)Currently,400000 km^2 of the land resources in Myanmar are suitable for agriculture,and of this amount 290000km^2 are highly suitable,accounting for nearly 40% of the country's land *** highly suitable land is distributed mainly in Magway,Sagaing,Ayeyarwady and Yangon *** provinces are also important grain production areas in Myanmar,and this serves to validate the effectiveness of the method used in this paper.

关键词： Myanmar agriculture land suitability MaxEnt AHP

Effects of global change and human disturbance on soil carbon cycling in boreal forest: A review

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Pedosphere 2023年第1期33卷 194-211页

作者： Pengshuai SHAO Hongyan HAN Jingkuan SUN Hongtu XIE Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Binzhou UniversityBinzhou 256603China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China

Increasing human demands for Earth’s resources are hastening many environmental changes and creating a need to incorporate the routine monitoring of ecosystem functions into forest *** global change and anthropogenic disturbances,soil carbon(C)cycling in terrestrial ecosystems is undergoing substantial changes that result in the transformation between soil C sources and ***,the forest C budget requires an understanding of the underlying soil C dynamic under environmental *** present review focuses on the response and feedback of soil C cycling to global change(climate warming and nitrogen(N)deposition)and human disturbances(fire and logging)and detects the association of soil C cycling with soil C and N efflux and inflow in boreal *** effects of climate warming and N deposition on soil C cycling are complex,especially at short-term temporal *** warming can decay soil organic matter(SOM)to emit substantial amounts of CO2,and differing warming durations result in different effects on soil C loss,ranging from ca.1 to 15 Mg C ha−***-term soil warming mainly reduces the labile soil C pool and increases the decomposition of recalcitrant soil C compounds(e.g.,lignin),whereas longer-term warming may limit soil C loss due to impoverished soil C substrate and microbial *** N addition is conducive to enhancing soil C storage(ca.2–22 Mg C ha−1),by increasing plant productivity including above-and belowground biomass;however,chronic N deposition or excess N addition can result in soil acidity,reducing N use efficiency and plant growth and further resulting in no changes or declines in soil C *** and logging lead to a large quantity of soil C loss via impaired plant productivity and increased organic matter degradation,exacerbating global *** particular,severe fire can cause a large amount of soil C loss,ca.16–34 Mg C ha−1 in the data we ***,the black C input induced by fire

关键词： climate warming forest C budget forest management N deposition soil microorganism terrestrial ecosystem

Optical frequency transfer link with remote site compensation

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chinese Optics Letters 2024年第9期22卷 68-73页

作者： Qi Zang Xiang Zhang Xue Deng Qian Zhou Dan Wang Yucan Zhang Jing Gao Dongdong Jiao Guanjun Xu Tao Liu Ruifang Dong Shougang Zhang National Time Service Centre Chinese Academy of SciencesXi’an 710600China Key Laboratory of Time Reference and Applications Chinese Academy of SciencesXi’an 710600China School of Communications and Information Engineering and School of Artificial Intelligence Xi’an University of Posts and TelecommunicationsXi’an 710121China University of chinese Academy of Sciences Beijing 100049China

In this paper,we present a remote time-base-free technique for a coherent optical frequency transfer system via *** the remote site,the thermal noise of the optical components is corrected along with the link phase noise caused by environmental *** this system,a 1×2 acousto-optic modulator(AOM)is applied at the remote site,with the first light being used to eliminate the noise of the remote time base and interface with remote users while the zeroth light is used to establish an active noise canceling *** this technique,a 10 MHz commercial oscillator,used as a time base at the remote site,does not contribute to the noise of the transferred *** experimental system is constructed using a 150 km fiber spool to validate the proposed *** compensation,the overlapping Allan deviation of the transfer link is 7.42×10^(-15)at 1 s integration time and scales down to 1.07×10^(-18)at 10,000 s integration *** uncertainty of the transmitted optical frequency is on the order of a few *** significantly reduces the time-base requirements and costs for multi-user applications without compromising transfer ***,these results show great potential for transferring ultra-stable optical frequency signals to remote sites,especially for point-to-multi-users.

关键词： optical frequency measurement remote site compensation ultra-stable laser fiber network

Robust H_∞ cluster synchronization analysis of Lurie dynamical networks

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chinese Physics B 2014年第4期23卷 162-170页

作者：郭凌年晓红潘欢邴志桐 College of Electrical Engineering Northwest University for Nationalities College of Information Science and Engineering Central South University College of Physics Electrical Information Engineering Ningxia University Institute of Modern Physics Chinese Academy of Sciences

The cluster synchronization problem of complex dynamical networks with each node being a Lurie system with exter- nal disturbances and time-varying delay is investigated in this paper. Some criteria for cluster synchronization with desired H∞ performance are presented by using a local linear control scheme. Firstly, sufficient conditions are established to realize cluster synchronization of the Lurie dynamical networks without time delay. Then, the notion of the cluster synchronized region is introduced, and some conditions guaranteeing the cluster synchronized region and unbounded cluster synchro- nized region are derived. Furthermore, the cluster synchronization and cluster synchronized region in the Lurie dynamical networks with time-varying delay are considered. Numerical examples are finally provided to verify and illustrate the theoretical results.

关键词： luster synchronization Lurie dynamics network H∞ performance time-varying delay

Hierarchical-control-based output synchronization of coexisting attractor networks

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chinese Physics B 2010年第2期19卷 127-134页

作者：宋运忠唐贻发 Complex networks Laboratory College of Electrical Engineering&AutomationHenan Polytechnic University State Key Laboratory of Scientific&Engineering Computing Academy of Mathematics&Systems ScienceChinese Academy of Sciences

This paper introduces the concept of hierarchical-control-based output synchronization of coexisting attractor networks. Within the new framework, each dynamic node is made passive at first utilizing intra-control around its own arena. Then each dynamic node is viewed as one agent, and on account of that, the solution of output synchronization of coexisting attractor networks is transformed into a multi-agent consensus problem, which is made possible by virtue of local interaction between individual neighbours; this distributed working way of coordination is coined as inter-control, which is only specified by the topological structure of the network. Provided that the network is connected and balanced, the output synchronization would come true naturally via synergy between intra and inter-control actions, where the rightness is proved theoretically via convex composite Lyapunov functions. For completeness, several illustrative examples are presented to further elucidate the novelty and efficacy of the proposed scheme.

关键词： hierarchical control passive control composite Lyapunov function the Newton--Leipnik equation attractor

Kuanxiong Aerosol(宽胸气雾剂)in Treatment of Angina Pectoris:A Literature Review and network Pharmacology

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chinese Journal of Integrative Medicine 2021年第6期27卷 470-480页

作者： ZHANG Yu-zhuo ZENG Rui-xiang ZHOU Yuan-shen ZHANG Min-zhou The Second Clinical College of Guangzhou University of chinese Medicine Guangzhou(510120)China Department of Critical Care Medicine the Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou(510120)China Division of Chest Pain Center Guangdong Provincial Hospital of Chinese MedicineGuangzhou(510120)China

Angina pectoris(AP)is the most common symptom of cardiovascular diseases,which seriously affects the quality of life in cardiovascular ***(KX)Aerosol(宽胸气雾剂),a compound preparation that consists of 5 traditional chinese medicines:Herba Asari,Rhizoma Alpiniae Officinarum,Lignum Santali Albi,Fructus Piperis Longi,and Borneolum,has been used in the treatment of AP for many years,exhibiting a significant curative effect and less *** the convenience and comprehensive understanding of KX Aerosol,this review systematically summarizes evidence on KX Aerosol in the treatment of AP including the pharmacological effects of its composition,clinical research,animal experiments,and network pharmacology ***,we highlight the research limitation of KX Aerosol at *** review may guide the clinical application of KX Aerosol and further provide a reference for the research of AP.

关键词： Kuanxiong Aerosol angina pectoris pharmacology clinical application network pharmacology

The impact of venetoclax based regimens in the preemptive of measurable residual disease in acute myeloid leukemia

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Blood Science 2022年第1期4卷 44-46页

作者： Qiuyun Fang Xiaoyuan Gong Yan Li Benfa Gong Yuntao Liu Kaiqi Liu Guangji Zhang Shuning Wei Dong Lin Bingcheng Liu Ying Wang Hui Wei Yingchang Mi Jianxiang Wang State Key Laboratory of Experimental Hematology National Clinical Research Center for Blood DiseasesHaihe Laboratory of Cell EcosystemInstitute of Hematology&Blood Diseases HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeNo.288 Nanjing RoadTianjinChina

To The Editor:The role of measurable residual disease(MRD)in prognosis and treatment in acute myeloid leukemia(AML)is *** have demonstrated the correlation between MRD and risks of relapse in adult AML:persistently positive MRD after induction is associated with a high risk of relapse,1,2 and these patients should consider allogeneic transplantation(allo-Hematopoietic Stem Cell Transplantation(HSCT))and clinical trial,even in favorable-risk ***,because of the financial issue or lack of suitable transplant donors,many of the patients could not receive allo-HSCT,so how to prolong the relapse-free survival of these patients remains a *** et al treated MRD-positive patients with azacytidine(AZA),and found pre-emptive therapy with AZA can prevent or substantially delay hematological relapse in MRD-positive patients with MDS(myelodysplastic syndrome)or AML who are at a high risk of relapse.

关键词： myeloid acute regimen