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| 1 | Temporal and spatial variations of the active layer along the Qinghai-Tibet Highway in a permafrost region显示文摘Using monitored active layer thickness(ALT) and environmental variables of 10 observation fields along the Qinghai-Tibet Highway in permafrost region of the Qinghai-Tibetan Plateau(QTP),a model for ALT estimation was developed.The temporal and spatial characteristics of the ALT were also analyzed.The results showed that in the past 30 years ALT in the study region increased at a rate of 1.33 cm a-1.Temperatures at the upper limit of permafrost and at 50 cm depth,along with soil cumulative temperature at 5 cm depth also exhibited a rising trend.Soil heat flux increased at a rate of 0.1 Wm-2 a-1.All the above changes demonstrated that the degradation of permafrost happened in the study region on the QTP.The initial thawing date of active layer was advanced,while the initial freezing date was delayed.The number of thawing days increased to a rate of 1.18 da-1.The variations of active layer were closely related to the permafrost type,altitude,underlying surface type and soil composition.The variations were more evident in cold permafrost region than in warm permafrost region,in high-altitude region than in low-altitude region,in alpine meadow region than in alpine steppe region;and in fine-grained soil region than in coarse-grained soil region. | LI Ren ZHAO Lin DING YongJian WU TongHua XIAO Yao DU ErJi LIU GuangYue QIAO YongPing | 2012 | Chinese Science Bulletin2012，57，35： | 51 |
| 2 | Cryospheric Science: research framework and disciplinary system显示文摘Cryospheric changes and their impacts have received increasing concern, extending the research to include the interactions between earth spheres and the impacts of and social adaptation to cryospheric changes. As a result, Cryospheric Science is rapidly developing. However, the research framework of Cryospheric Science has not completely been set up, and the intension and extension of Cryospheric Science are unclear.Following a literature review, the research framework for Cryospheric Science and the discipline components are analysed in this paper. We consider that Cryospheric Science is an inevitable product of international research on the earth and environmental changes as well as on human sustainable development. It will not only strengthen the linkage between the cryosphere and other earth spheres by deepening traditional research areas, but will also bring more focus on the critical roles of the cryosphere in interactions between earth spheres, and will enhance the relationship between cryospheric change and climate, ecology, hydrology, surface environment and sustainable development. The disciplinary tree of Cryospheric Science is developed following the mainstream of change-impacts adaptation. The disciplines of Cryospheric Science were teased out against characteristics of traditional branches and the developing interdisciplinary branches of cryosphere elements, which will provide reference to Cryospheric Science as it systematically grows to maturity. | Dahe Qin Yongjian Ding Cunde Xiao Shichang Kang Jianwen Ren Jianping Yang Shiqiang Zhang | 2018 | National Science Review2018，5，2： | 42 |
| 3 | Initial estimate of the contribution of cryospheric change in China to sea level rise显示文摘Recent studies have shown that cryospheric melting is becoming the dominant factor responsible for sea level rise,and that the melt-water from mountain glaciers and ice caps has comprised the majority of the cryospheric contribution since 2003.Analysis of the estimations of cryospheric melt-water and precipitation in glacier regions indicated that the potential contribution of the cryosphere in China is 0.14 to 0.16 mm a–1,of which approximately 0.12 mm a–1 is from glaciers.The contribution of glaciers in the outflow river basins is about 0.07 mm a–1,accounting for 6.4%of the total from global glaciers and ice caps. | REN JiaWen YE BaiSheng DING YongJian LIU ShiYin | 2011 | Chinese Science Bulletin2011，56，16： | 9 |
| 4 | Monthly ratios of PAR to global solar radiation measured at northern Tibetan Plateau, China显示文摘 | Li Ren Zhao Lin Ding Yongjian | 2010 | Solar Energy2010，84，6： | 1 |
| 5 | Flexibility-based finite element analysis for structures with random material properties 显示文摘 | Ren Yongjian I Elishakoff | 1998 | Journal of Applied Mechanics1998，65，4： | 1 |
| 6 | A Client Selection Method Based on Loss Function Optimization for Federated Learning显示文摘Federated learning is a distributedmachine learningmethod that can solve the increasingly serious problemof data islands and user data privacy,as it allows training data to be kept locally and not shared with other users.It trains a globalmodel by aggregating locally-computedmodels of clients rather than their rawdata.However,the divergence of local models caused by data heterogeneity of different clients may lead to slow convergence of the global model.For this problem,we focus on the client selection with federated learning,which can affect the convergence performance of the global model with the selected local models.We propose FedChoice,a client selection method based on loss function optimization,to select appropriate local models to improve the convergence of the global model.It firstly sets selected probability for clients with the value of loss function,and the client with high loss will be set higher selected probability,which can make them more likely to participate in training.Then,it introduces a local control vector and a global control vector to predict the local gradient direction and global gradient direction,respectively,and calculates the gradient correction vector to correct the gradient direction to reduce the cumulative deviationof the local gradient causedby theNon-IIDdata.Wemake experiments to verify the validity of FedChoice on CIFAR-10,CINIC-10,MNIST,EMNITS,and FEMNIST datasets,and the results show that the convergence of FedChoice is significantly improved,compared with FedAvg,FedProx,and FedNova. | Yan Zeng Siyuan Teng Tian Xiang Jilin Zhang Yuankai Mu Yongjian Ren Jian Wan | 2023 | Computer Modeling in Engineering & Sciences2023，，10： | 0 |
| 7 | APPLICATION OF STOCHASTIC FINITE ELEMENT METHOD TO STRENGTH AND STABILITY ANALYSIS OF EARTH DAMS显示文摘This paper applies the stochastic finite element method to analyse thestatistics of stresses in earth dams and assess the safety and reliability of the dams.Formulations of the stochastic finite element method are briefly reviewed and theprocedure for assessing dam’s strength and stability is described.As an example,adetailed analysis for an actual dam-Nululin dam is performed.A practical method forstudying built-dams based on the prototype observation data is described. | Yongjian, Ren Guoqing, Wang Derong, Wei Jizhong, Shi | 1994 | Acta Mechanica Solida Sinica1994，7，1： | 0 |
| 8 | Performance Prediction Based Workload Scheduling in Co-Located Cluster显示文摘Cloud service providers generally co-locate online services and batch jobs onto the same computer cluster,where the resources can be pooled in order to maximize data center resource utilization.Due to resource competition between batch jobs and online services,co-location frequently impairs the performance of online services.This study presents a quality of service(QoS)prediction-based schedulingmodel(QPSM)for co-locatedworkloads.The performance prediction of QPSM consists of two parts:the prediction of an online service’s QoS anomaly based on XGBoost and the prediction of the completion time of an offline batch job based on randomforest.On-line service QoS anomaly prediction is used to evaluate the influence of batch jobmix on on-line service performance,and batch job completion time prediction is utilized to reduce the total waiting time of batch jobs.When the same number of batch jobs are scheduled in experiments using typical test sets such as CloudSuite,the scheduling time required by QPSM is reduced by about 6 h on average compared with the first-come,first-served strategy and by about 11 h compared with the random scheduling strategy.Compared with the non-co-located situation,QPSM can improve CPU resource utilization by 12.15% and memory resource utilization by 5.7% on average.Experiments show that the QPSM scheduling strategy proposed in this study can effectively guarantee the quality of online services and further improve cluster resource utilization. | Dongyang Ou Yongjian Ren Congfeng Jiang | 2024 | Computer Modeling in Engineering & Sciences2024，139，5： | 0 |
| 9 | Grand canonical Monte Carlo simulation for hydrogen uptakes based on nanoporous NaBH_4显示文摘A new hydrogen storage route of 3D nanoporous sodium borohydride (NPSB) generated by removing special atoms is proposed in this work. Three different size pores of NPSB-1 (7), NPSB-2 (10) and NPSB-3 (14) are presented, and the hydrogen storage capacities of these NPSBs are simulated by employing a grand canonical Monte Carlo (GCMC) procedure for a temperature range of 77-298 K and a pressure range of 0.1-100 bar. The effects of pore diameter, temperature and pressure on the hydrogen adsorption have been examined. The results show that the adsorption of hydrogen decreases and increases with increasing temperature and hydrogen pressure, respectively. It also reflects that the hydrogen adsorption capacities at higher pressures are dependent on pore diameter, while independent of pore diameter at lower pressures. | REN Juan ZHANG Hong TANG YongJian WU WeiDong WANG ChaoYang | 2013 | Science China(Physics,Mechanics & Astronomy)2013，56，8： | 0 |
| 10 | KINETIC STUDY ON THE REMOVAL OF LEAD AND SILVERFROMCRUDEBISMUTHBYANODEREFINING显示文摘KINETICSTUDYONTHEREMOVALOFLEADANDSILVERFROMCRUDEBISMUTHBYANODEREFININGKINETICSTUDYONTHEREMOVALOFLEADANDSILVERFROMCRUDEBISMUTH... | Zhang Yongjian Ren Hongyan Xie Zhong(Department of Non-Ferrous Metallurgy, Central South University of Technology, Changsha, 410083, China) | 1994 | Journal of Central South University1994，6，1： | 0 |
| 11 | A theoretical study of electronic excited states of photosynthetic reaction center in Rhodopseudomonas viridis显示文摘The electronic singlet vertical excited states of photosynthetic reaction center (PSRC) in Rhodopseudomonas (Rps.) viridis were investigated by ZINDO and INDO/S methods. The effects of the interactions of pigment-pigment and pigment-protein on the electronic excitations were examined. The calculation results showed that the interactions of pigment-pigment and pigment-protein play an important role in reasonably assigning the experimental absorption and circular dichroism (CD) spec-tra of PSRC in Rps. virids. By comparing the theoretically computed excited states with the experi-mental absorption and CD spectra, satisfactory assignments of the experimental spectroscopic peaks were achieved. | REN Yanliang CHENG Lin WAN Jian LI Yongjian LIU Junjun YANG Guangfu ZHANG Lihua YANG Song | 2006 | Science China Chemistry2006，49，1： | 0 |
| 12 | π~±Elastic Scattering and Excitation Function of Pion SCX Reaction on ^(13)C | Ren Yongjian~(1,2) Gu Jianzhong~1) Lei Yian~1) Zeng Guomo~(1,3)1)Institute of Theoretical Physics,the Chinese Academy of Sciences,P.O.Box 2735,Beijing 1000802)Teaching and Research Section of Physics,Agriculture University of China,Beijing 1000833)Department of Physics,Jiliu University,Changchun 130023 | 1997 | Chinese journal of nuclear physics1997，，3： | 0 |
| 13 | Regulation of 2-acetyl-1-pyrroline and grain quality in early-season indica fragrant rice by nitrogen and silicon fertilization under different plantation methods显示文摘Fragrant rice has a high market value,and it is a popular rice type among consumers owing to its pleasant flavor.Plantation methods,nitrogen(N)fertilizers,and silicon(Si)fertilizers can affect the grain yield and fragrance of fragrant rice.However,the core commercial rice production attributes,namely the head rice yield(HRY)and 2-acetyl-1-pyrroline(2-AP)content of fragrant rice,under various nitrogen and silicon(N-Si)fertilization levels and different plantation methods remain unknown.The field experiment in this study was performed in the early seasons of 2018 and 2019 with two popular indica fragrant rice cultivars(Yuxiangyouzhan and Xiangyaxiangzhan).They were grown under six N-Si fertilization treatments(combinations of two levels of Si fertilizer,0 kg Si ha^(−1)(Si0)and 150 kg Si ha^(−1)(Si1),and three levels of N fertilizer,0 kg N ha^(−1)(N0),150 kg N ha^(−1)(N1),and 220 kg N ha^(−1)(N2))and three plantation methods(artificial transplanting(AT),mechanical transplanting(MT),and mechanical direct-seeding(MD)).The results showed that the N-Si fertilization treatments and all the plantation methods significantly affected the HRY and 2-AP content and related parameters of the two different fragrant rice cultivars.Compared with the Si0N0 treatment,the N-Si fertilization treatments resulted in higher HRY and 2-AP contents.The rates of brown rice,milled rice,head rice,and chalky rice of the fragrant rice also improved with the N-Si fertilization treatments.The N-Si fertilization treatments increased the activities of N metabolism enzymes and the accumulation of N and Si in various parts of the fragrant rice,and affected their antioxidant response parameters.The key parameters for the HRY and 2-AP content were assessed by redundancy analysis.Furthermore,the structural equation model revealed that the Si and N accumulation levels indirectly affected the HRY by affecting the N metabolism enzyme activity,N use efficiency,and grain quality of fragrant rice.Moreover,high N and Si accumulation directly promoted the 2-AP content or affected the antioxidant response parameters and indirectly regulated 2-AP synthesis.The interactions of the MT method with the N-Si fertilization treatments varied in the fragrant rice cultivars in terms of the HRY and 2-AP content,whereas the MD method was beneficial to the 2-AP content in both fragrant rice cultivars under the N-Si fertilization treatments. | Yongjian Chen Lan Dai Siren Cheng Yong Ren Huizi Deng Xinyi Wang Yuzhan Li Xiangru Tang Zaiman Wang Zhaowen Mo | 2024 | Journal of Integrative Agriculture2024，23，2： | 0 |
| 14 | Mechanical properties of flax fibres treated by alkaline,enzyme and steam-heat显示文摘In recent years there has been interest in using flax fibres to produce composites because of a number of attributes, including low density, biodegradability and high mechanical properties. It was found that treatment of flax fibres may be required to improve the bond quality with a resin. These treatments also have an impact on the properties of the fibres themselves. The objective of this project was to evaluate the impact of three treatment methods on the mechanical properties of flax fibres. The three treatment methods were alkaline, enzyme and steam-heat. After treatment, flax fibres were tested in tension using a universal test machine. Results showed that tensile strength and Young's modulus of flax fibre can be enhanced significantly by the three treatment methods, compared with untreated flax fibres. Enzyme treatment was shown to be the best approach to improve mechanical properties of flax fibre than alkaline and steam-heat treatment. | Cao Yongjian Chui YingHei Chan Felisa Gong Meng Ren Haiqing Wang Ge | 2018 | 林业与环境科学2018，34，3： | 0 |
| 15 | A Possible Abrupt Change in Summer Precipitation over Eastern China around 2009显示文摘Historical studies have shown that summer rainfall in eastern China undergoes decadal variations,with three apparent changes in the late 1970s,1992,and the late 1990s.The present observational study indicates that summer precipitation over eastern China likely underwent a change in the late 2000s,during which the main spatial pattern changed from negative–positive–negative to positive–negative in the meridional direction.This change in summer precipitation over eastern China may have been associated with circulation anomalies in the middle/upper troposphere.A strong trough over Lake Baikal created a southward flow of cold air during 2009–15,compared with 1999–2008,while the westward recession of the western Pacific subtropical high strengthened the moisture transport to the north,creating conditions that were conducive for more rainfall in the north during this period.The phase shift of the Pacific Decadal Oscillation in the late 2000s led to the Pacific–Japan-type teleconnection wave train shifting from negative to positive phases,resulting in varied summer precipitation over eastern China. | Yongjian REN Lianchun SONG Zunya WANG Ying XIAO Bing ZHOU | 2017 | Journal of Meteorological Research2017，31，2： | 0 |
| 16 | Anatomical morphology of the aortic valve in Chinese aortic stenosis patients and clinical results after downsize strategy of transcatheter aortic valve replacement显示文摘Background:The study aimed to describe the aortic valve morphology in Chinese patients underwent transcatheter aortic valve replacement(TAVR)for symptomatic severe aortic stenosis(AS),and the impact of sizing strategies and related procedural outcomes.Methods:Patients with severe AS who underwent TAVR were consecutively enrolled from 2012 to 2019.The anatomy and morphology of the aortic root were assessed.'Downsize'strategy was preformed when patients had complex morphology.The clinical outcomes of patients who performed downsize strategy were compared with those received annular sizing strategy.The primary outcome was device success rate,and secondary outcomes included Valve Academic Research Consortium-3 clinical outcomes variables based on 1-year follow-up.Results:A total of 293 patients were enrolled.Among them,95 patients(32.4%)had bicuspid aortic valve.The calcium volume(Hounsfield Unit-850)of aortic root was 449.90(243.15-782.15)mm3.Calcium is distributed mostly on the leaflet level.Downsize strategy was performed in 204 patients(69.6%).Compared with the patients who performed annular sizing strategy,those received downsize strategy achieved a similar device success rate(82.0%[73]vs.83.3%[170],P=0.79).Aortic valve gradients(downsize strategy group vs.annular sizing group,11.28 mmHg vs.11.88 mmHg,P=0.64)and percentages of patients with moderate or severe paravalvular regurgitation 2.0%(4/204)vs.4.5%(4/89),P=0.21were similar in the two groups at 30 days after TAVR.These echocardiographic results were sustainable for one year.Conclusions:Chinese TAVR patients have more prevalent bicuspid morphology and large calcium volume of aortic root.Calcium is distributed mostly on the leaflet level.Compare with annular sizing strategy,downsize strategy provided a non-inferior device success rate and transcatheter heart valve hemodynamic performance in self-expanding TAVR procedure. | Guannan Niu Walid Ben Ali Moyang Wang Hasan Jilaihawi Haitong Zhang Qian Zhang Yunqing Ye Xinmin Liu Jing Yao Qinghao Zhao Yubin Wang Zheng Zhou Lizhi Zhang Xinshuang Ren Yunqiang An Bin Lu Thomas Modine Yongjian Wu Guangyuan Song | 2022 | Chinese Medical Journal2022，135，24： | 0 |
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