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| 1 | 348-YEAR PRECIPITATION RECONSTRUCTION FROM TREE-RINGS FOR THE NORTH SLOPE OF THE MIDDLE TIANSHAN MOUNTAINS显示文摘Correlation census shows that the correlation between the tree-ring chronologies in the Urumqi River Basin and precipitation during July in the last year to February in the concurrent year is significant, and the best single correlation coefficient is 0.74, with significance level of 0. 0001.Using two residual chronologies collected from west Baiyanggou and Boerqingou, precipitation for 348 years can be reconstructed in the North Slope of middle Tianshan Mountains, its explained variance is 62%. According to much verification from independent precipitation data, historical climate records, glacier and other data, it shows that the reconstructed precipitation series of 348 years is reliable. Analysis of precipitation features indicates that there were three wet periods occurring during 1671 (?) -1692, 1716-1794 and 1825-1866 and three dry periods during 1693 - 1715, 1795- 1824 and 1867- 1969. Two wet periods, during 1716- 1794 and 1825 - 1866,correspond to the times of the second and the third glacial terminal moraine formation, which is in front of No. 1 glacier in Urumqi River source. According to computation, corresponding annual precipitation amounts are 59 mm and 30 mm more than now. The reconstructed precipitation series has a significant drying trend from 1716 to 1969, and has better representativeness to the precipitation of Urumqi and Changji Prefecture on the North Slope of Tianshan Mountains. | 袁玉江 李江风 张家宝 | 2001 | Acta meteorologica Sinica2001，15，1： | 27 |
| 2 | Measure theory of statistical convergence显示文摘The question of establishing measure theory for statistical convergence has been moving closer to center stage, since a kind of reasonable theory is not only fundamental for unifying various kinds of statistical convergence, but also a bridge linking the studies of statistical convergence across measure theory, integration theory, probability and statistics. For this reason, this paper, in terms of subdifferential, first shows a representation theorem for all finitely additive probability measures defined on the σ-algebra A of all subsets of N, and proves that every such measure can be uniquely decomposed into a convex combination of a countably additive probability measure and a statistical measure (i.e. a finitely additive probability measure μ with μ(k) = 0 for all singletons {k}). This paper also shows that classical statistical measures have many nice properties, such as: The set S of all such measures endowed with the topology of point-wise convergence on A forms a compact convex Hausdorff space; every classical statistical measure is of continuity type (hence, atomless), and every specific class of statistical measures fits a complementation minimax rule for every subset in N. Finally, this paper shows that every kind of statistical convergence can be unified in convergence of statistical measures. | CHENG LiXin LIN GuoChen LAN YongYi LIU Hui | 2008 | Science China Mathematics2008，51，12： | 26 |
| 3 | VIC distributed hydrological model to predict climate change impact in the Hanjiang Basin显示文摘The climate impact studies in hydrology often rely on climate change information at fine spatial resolution. However, the general circulation model (GCM), which is widely used to simulate future climate scenario, operates on a coarse scale and does not provide reliable data on local or regional scale for hydrological modeling. Therefore the outputs from GCM have to be downscaled to obtain the information fit for hydrologic studies. The variable infiltration capacity (VIC) distributed hydrological model with 9×9 km2 grid resolution was applied and calibrated in the Hanjiang Basin. Validation results show that SSVM can approximate observed precipitation and temperature data reasonably well, and that the VIC model can simulate runoff hydrograph with high model efficiency and low relative error. By applying the SSVM model, the trends of precipitation and temperature (including daily mean temperature, daily maximum temperature and daily minimum temperature) projected from CGCM2 under A2 and B2 scenarios will decrease in the 2020s (2011―2040), and increase in the 2080s (2071―2100). However, in the 2050s (2041―2070), the precipitation will be decreased under A2 scenario and no significant changes under B2 scenario, but the temperature will be not obviously changed under both climate change scenarios. Under both climate change scenarios, the impact analysis of runoff, made with the downscaled precipitation and temperature time series as input of the VIC distributed model, has resulted in a decreasing trend for the 2020s and 2050s, and an overall increasing trend for the 2080s. | GUO ShengLian GUO Jing ZHANG Jun CHEN Hua | 2009 | Science China(Technological Sciences)2009，52，11： | 23 |
| 4 | A statistical model for porous structure of rocks显示文摘The geometric features and the distribution properties of pores in rocks were in- vestigated by means of CT scanning tests of sandstones. The centroidal coordi- nates of pores, the statistic characterristics of pore distance, quantity, size and their probability density functions were formulated in this paper. The Monte Carlo method and the random number generating algorithm were employed to generate two series of random numbers with the desired statistic characteristics and prob- ability density functions upon which the random distribution of pore position, dis- tance and quantity were determined. A three-dimensional porous structural model of sandstone was constructed based on the FLAC3D program and the information of the pore position and distribution that the series of random numbers defined. On the basis of modelling, the Brazil split tests of rock discs were carried out to ex- amine the stress distribution, the pattern of element failure and the inosculation of failed elements. The simulation indicated that the proposed model was consistent with the realistic porous structure of rock in terms of their statistic properties of pores and geometric similarity. The built-up model disclosed the influence of pores on the stress distribution, failure mode of material elements and the inosculation of failed elements. | JU Yang1,2, YANG YongMing1, SONG ZhenDuo3 & XU WenJing4 1 State Key Laboratory of Coal Resources and Safe Mining, China University of Mining & Technology, Beijing 100083, China 2 Department of Mechanical and Manufacturing Engineering, The University of Calgary, 2500 University Drive NW Calgary, AB T2N 1N4, Canada 3 China National Coal Mining Equipment Co. Ltd, Beijing 100011, China 4 Department of Materials and Metallurgy, The University of Utah, Salt Lake City, Utah 84112, USA | 2008 | Science China(Technological Sciences)2008，51，11： | 21 |
| 5 | A Novel 3D Non-Stationary UAV-MIMO Channel Model and Its Statistical Properties显示文摘The wireless communication systems based on Unmanned Aerial Vehicles(UAVs) have found a wide range of applications recently. In this paper, we propose a new three-dimensional(3 D) non-stationary multiple-input multiple-output(MIMO) channel model for the communication links between the UAV and mobile terminal(MT). The new model originates the traditional geometry-based stochastic models(GBSMs) but considers the non-stationary propagation environment due to the rapid movements of the UAV, MT, and clusters. Meanwhile, the upgrade time evolving algorithms of time-variant channel parameters, i.e., the path number based on birth-death processes of clusters, path delays, path powers, and angles of arrival and departure, are developed and optimized. In addition, the statistical properties of proposed GBSM including autocorrelation function(ACF), cross-correlation function(CCF), and Doppler power spectrum density(DPSD) are investigated and analyzed. Simulation results demonstrate that our proposed model provides a good agreement on the statistical properties with the corresponding derived theoretical ones, which indicates its usefulness for the performance evaluation and validation of the UAV based communication systems. | Qiuming Zhu Kaili Jiang Xiaomin Chen Weizhi Zhong Ying Yang | 2018 | China Communications2018，15，12： | 18 |
| 6 | Probabilistic stability analyses of undrained slopes by 3D random fields and finite element methods显示文摘A long slope consisting of spatially random soils is a common geographical feature. This paper examined the necessity of three-dimensional(3 D) analysis when dealing with slope with full randomness in soil properties. Although 3 D random finite element analysis can well reflect the spatial variability of soil properties, it is often time-consuming for probabilistic stability analysis. For this reason, we also examined the least advantageous(or most pessimistic) cross-section of the studied slope. The concept of'most pessimistic' refers to the minimal cross-sectional average of undrained shear strength. The selection of the most pessimistic section is achievable by simulating the undrained shear strength as a 3 D random field. Random finite element analysis results suggest that two-dimensional(2 D) plane strain analysis based the most pessimistic cross-section generally provides a more conservative result than the corresponding full 3 D analysis. The level of conservativeness is around 15% on average. This result may have engineering implications for slope design where computationally tractable 2 D analyses based on the procedure proposed in this study could ensure conservative results. | Yong Liu Wengang Zhang Lei Zhang Zhiren Zhu Jun Hu Hong Wei | 2018 | Geoscience Frontiers2018，9，6： | 17 |
| 7 | Hepatocellular carcinoma: Clinical study of long-term survival and choice of treatment modalities显示文摘AIM: To analyze the prognostic factors of 5-year survival and 10-year survival in hepatocellular carcinoma (HCC) patients, and to explore the reasons for longterm survival and provide choice of treatment modalities for HCC patients. METHODS: From January 1990 to October 2012, 8450 HCC patients were included in a prospective database compiled by the Information Center after hospital admission. Long-term surviving patients were included in a 10-year survival group (520 patients) and a 5-year survival group (1516 patients) for analysis. The long-term survival of HCC patients was defined as the survival of 5 years or longer. Clinical and biologic variables were assessed using univariate and multivariate analyses. The survival of patients was evaluated by follow-up data. RESULTS: The long-term survival of HCC patients was associated with the number of lesions, liver cirrhosis and Child-Pugh classification. It was not found to be associated with tumor diameter, histological stage, and pretreatment level of serum α-fetoprotein. The differences in clinical factors between the 5-year survival and the 10-year survival were found to be the number of lesions, liver cirrhosis, Child-Pugh classification, and time elapsed until first recurrence or metastasis. The survival period of different treatment modalities in the patients who survived for 5 years and 10 years showed significant differences: (in order of significance) surgery alone > surgery-transcatheter arterial chemoembolization (TACE) > TACE-radiofrequency ablation (RFA) > TACE alone > surgery-TACE-RFA. The 10-year survival of HCC patients was not associated with the choice of treatment modality.CONCLUSION: This retrospective study elucidated survival outcomes, prognostic factors affecting survival and treatment modalities in HCC patients. | Ke-Tong Wu Cun-Chuan Wang Li-Gong Lu Wei-Dong Zhang Fu-Jun Zhang Feng Shi Chuan-Xing Li | 2013 | World Journal of Gastroenterology2013，19，23： | 15 |
| 8 | Statistical values of valence electron structure parameters applied to research on phase transition temperature and eutectoid reaction of titanium alloy显示文摘Based on the empirical electron theory of solids and molecules (EET), the statisti- cal values of valence electron structure parameters SnA and SEA which can char- acterize the properties of alloy phases are calculated, and influences of alloying elements (e.g., V, Nb, Mo, Hf, Zr, Fe, Mn, Co, Cr, Si, and so on) on the phase transi- tion temperature and eutectoid reaction of titanium alloy are discussed with the statistical values of valence electron structure parameters. The research results agree well with real situations. | Cheng Lin ZhiLin Liu | 2008 | Science China(Technological Sciences)2008，51，11： | 14 |
| 9 | Metabolomics analysis and rapid identification of changes in chemical ingredients in crude and processed Astragali Radix by UPLC-QTOF-MS combined with novel informatics UNIFI platform显示文摘Astragali Radix, the root of Astragalus membranaceus(Fisch.) Bge. var. mongholicus(Bge.) Hsiao or Astragalus membranaceus(Fisch.) Bge., is widely used as a tonic decoction pieces in the clinic of traditional Chinese medicine(TCM). Astragali Radix has various processed products with varying pharmacological actions. There is no modern scientific evidence to explain the differences in pharmacological activities and related mechanisms. In the present study, we explore the changes in chemical components in Astragali Radix after processing, by ultra-high performance liquid chromatography quadrupole time-of-flight mass spectrometry(UPLC-QTOF-MS) combined with novel informatics UNIFI platform and multivariate statistical analysis. Our results showed that the crude and various processed products could be clearly separated in PCA scores plot and 15 significant markers could be used to distinguish crude and various processed products by OPLS-DA in UNIFI platform. In conclusion, the present study provided a basis of chemical components for revealing connotation of different processing techniques on Astragali Radix. | LIU Peng-Peng SHAN Guo-Shun ZHANG Fan CHEN Jiang-Ning JIA Tian-Zhu | 2018 | Chinese Journal of Natural Medicines2018，16，9： | 12 |
| 10 | A Statistical Analysis of China's Traffic Tunnel Development Data显示文摘 | Yong Zhao Pengfei Li | 2018 | Engineering2018，4，1： | 11 |
| 11 | Statistical Characteristics of Suction Pressure Signals for a Centrifugal Pumpunder Cavitating Conditions显示文摘Centrifugal pumps are often used in operating conditions where they can be susceptible to premature failure. The cavitation phenomenon is a common fault in centrifugal pumps and is associated with undesired effects. Among the numerous cavitation detection methods, the measurement of suction pressure fluctuation is one of the most used methods to detect or diagnose the degree of cavitation in a centrifugal pump. In this paper, a closed loop was established to investigate the pump cavitation phenomenon, the statistical parameters for PDF(Probability Density Function), Variance and RMS(Root Mean Square) were used to analyze the relationship between the cavitation performance and the suction pressure signals during the development of cavitation. It is found that the statistical parameters used in this research are able to capture critical cavitation condition and cavitation breakdown condition, whereas difficult for the detection of incipient cavitation in the pump. At part-load conditions, the pressure fluctuations at the impeller inlet show more complexity than the best efficiency point(BEP). Amplitude of PDF values of suction pressure increased steeply when the flow rate dropped to 40 m^3/h(the design flow rate was 60 m^3/h). One possible reason is that the flow structure in the impeller channel promotes an increase of the cavitation intensity when the flow rate is reduced to a certain degree. This shows that it is necessary to find the relationship between the cavitation instabilities and flow instabilities when centrifugal pumps operate under part-load flow rates. | LI Xiaojun YU Benxu JI Yucheng LU Jiaxin YUAN Shouqi | 2017 | Journal of Thermal Science2017，26，1： | 11 |
| 12 | Integrated metabolomic profiling for analysis of antilipidemic effects of Polygonatum kingianum extract on dyslipidemia in rats显示文摘AIM To identify the effects and mechanism of action of Polygonatum kingianum(P. kingianum) on dyslipidemia in rats using an integrated untargeted metabolomic method.METHODS A rat model of dyslipidemia was induced with a high-fat diet(HFD) and rats were given P. kingianum [4 g/(kg·d)] intragastrically for 14 wk. Changes in serum and hepatic lipid parameters were evaluated. Metabolites in serum, urine and liver samples were profiled using ultra-highperformance liquid chromatography/mass spectrometry followed by multivariate statistical analysis to identify potential biomarkers and metabolic pathways.RESULTS P. kingianum significantly inhibited the HFD-induced increase in total cholesterol and triglyceride in the liver and serum. P. kingianum also significantly regulated metabolites in the analyzed samples toward normal status. Nineteen, twenty-four and thirty-eight potential biomarkers were identified in serum, urine and liver samples, respectively. These biomarkers involved biosynthesis of phenylalanine, tyrosine, tryptophan, valine, leucine and isoleucine, along with metabolism of tryptophan, tyrosine, phenylalanine, starch, sucrose, glycerophospholipid, arachidonic acid, linoleic acid, nicotinate, nicotinamide and sphingolipid.CONCLUSION P. kingianum alleviates HFD-induced dyslipidemia by regulating many endogenous metabolites in serum, urine and liver samples. Collectively, our findings suggest that P. kingianum may be a promising lipid regulator to treat dyslipidemia and associated diseases. | Xing-Xin Yang Jia-Di Wei Jian-Kang Mu Xin Liu Jin-Cai Dong Lin-Xi Zeng Wen Gu Jing-Ping Li Jie Yu | 2018 | World Journal of Gastroenterology2018，24，48： | 8 |
| 13 | Spatial prediction of landslide susceptibility using GIS-based statistical and machine learning models in Wanzhou County,Three Gorges Reservoir, China显示文摘Landslide susceptibility mapping is vital for landslide risk management and urban planning.In this study,we used three statistical models[frequency ratio,certainty factor and index of entropy(IOE)]and a machine learning model[random forest(RF)]for landslide susceptibility mapping in Wanzhou County,China.First,a landslide inventory map was prepared using earlier geotechnical investigation reports,aerial images,and field surveys.Then,the redundant factors were excluded from the initial fourteen landslide causal factors via factor correlation analysis.To determine the most effective causal factors,landslide susceptibility evaluations were performed based on four cases with different combinations of factors('cases').In the analysis,465(70%)landslide locations were randomly selected for model training,and 200(30%)landslide locations were selected for verification.The results showed that case 3 produced the best performance for the statistical models and that case 2 produced the best performance for the RF model.Finally,the receiver operating characteristic(ROC)curve was used to verify the accuracy of each model's results for its respective optimal case.The ROC curve analysis showed that the machine learning model performed better than the other three models,and among the three statistical models,the IOE model with weight coefficients was superior. | Ting Xiao Kunlong Yin Tianlu Yao Shuhao Liu | 2019 | Acta Geochimica2019，38，5： | 8 |
| 14 | CLOSED TRANS-SCALE STATISTICAL MICRODAMAGE MECHANICS显示文摘Damage and failure due to distributed microcracks or microvoidsare on the challenging frontiers of solid mechanics. This appeals strongly to toolsnot yet fully developed in continuum damage mechanics, in particular to irreversiblestatistical thermodynamics and a unified macroscopic equations of mechanics andkinetic equations of microstructural transformations. This review provides the stateof the art in statistical microdamage mechanics. (1) It clarifies on what level of approximation continuum damage mechanicsworks. Particularly, D-level approximation with dynamic function of damage appearsto be a proper closed trans-scale formulation of the problem. (2) It provides physical foundation of evolution law in damage mechanics. Es-sentially, the damage-dependent feature of the macroscopic evolution law is due tothe movement of microdamage front, resulting from microdamage growth. (3) It is found that intrinsic Deborah number D, a ratio of nucleation rateover growth rate of microdamage, is a proper indication of critical damage in damagemechanics, based on the idea of damage localization. (4) It clearly distinguishes the non-equilibrium damage evolution from equilib-rium phase transition, like percolation. Finally, some comments on its limitations are made. | 白以龙 夏蒙棼 柯孚久 李晖凌 | 2002 | Acta Mechanica Sinica2002，18，1： | 7 |
| 15 | Integral Recrystallization Modelling显示文摘We present models designed to represent the evolution of microstructure and crystallographic texture during recrystallization. For engineering applications the models are tied to a finite element approach. A connection to the deformed microstructure is established by dislocation theory of work hardening and Taylor type texture simulations. For temporal and spatial resolution a modified cellular automaton model was developed. A fast statistical approach for prediction of recrystallization kinetics and texture development discrete in time is presented. Predictions of the models are compared with experimental data. | G. Gottstein, V. Marx, R. Sebald Institut furr Metallkunde und Metallphysik, RWTH Aachen, 52056 Aachen, Germany | 2000 | Journal of Shanghai Jiaotong university(Science)2000，5，1： | 7 |
| 16 | Physical Layer Security with Its Applications in 5GNetworks: A Review显示文摘5G network is expected to support massive user connections and exponentially increasing wireless services,which makes network security unprecedentedly important.Unlike traditional security-guaranteeing techniques which rely heavily on cryptographic approaches at upper layers of the protocol stack,physical-layer security(PLS) solutions fully take advantages of the characteristics of wireless channels to degrade the received signal qualities at the malicious users,and realize keyless secure transmission via signal design and signal processing techniques.PLS avoids the difficulties in the distribution and management of secret keys,and provides flexible security levels through adaptive transmission protocol design.Moreover,PLS techniques match the features of 5G networks well.Therefore,the application of PLS to 5G networks is a promising solution to address the security threats.This article presents a comprehensive review of the state-of-the-art PLS techniques,and discusses their applications in 5G networks.We first summarize the principle and advantages of PLS techniques,and point out the reasons why PLS is suitable for 5G networks.Then,we review the existing PLS methods in literature,and highlight severalPLS solutions that are expected to be applied in 5G networks.Finally,we conclude this article and figure out some further research directions. | Li Sun Qinghe Du | 2017 | China Communications2017，14，12： | 7 |
| 17 | Rock-soil slope stability analysis by two-phase random media and finite elements显示文摘To investigate the strong random nature of the geometric interfaces between soil and rock, a rock-soil slope is considered as a two-phase random medium. A nonlinear translation of a Gaussian field is utilized to simulate the two-phase random media, such that the soil(or rock) volume fraction and the inclination of the soil layer can be examined. The finite element method with random media incorporated as the material properties is used to determine the factor of safety of the rock-soil slope. Monte-Carlo simulations are used to estimate the statistical characteristics of the factor of safety. The failure mode of the rock-soil slope is examined by observing the maximum principal plastic strain at incipient slope failure. It is found that the critical surface of a rock-soil slope is fairly irregular, and it significantly differs from that of a pure soil slope. The factor of safety is sensitive to the soil volume faction, but it is predictable. The average factor of safety could be well predicted by the weighted harmonic average between the strength of soil and rock; the prediction model is practical and simple. Parametric studies on the inclination of the soil layer demonstrate that the most instable scenario occurs when the slope angle is consistent with the inclination of the soil layer. | Yong Liu Huawen Xiao Kai Yao Jun Hu Hong Wei | 2018 | Geoscience Frontiers2018，9，6： | 7 |
| 18 | Modification of energy balance equations in Statistical Energy Analysis显示文摘The energy balance equations in the Classical Statistical Energy Analysis (CSEA) are modified by the equations of power flow among the thtee serial coupled oscinators. The modified equations include not only the direct power flow, but also the indirect power flow. The parameters in the modified equations can be expressed by those in the classical equations when the accuracy of the predicted results is able to satisfy the needs for ellgineering. | SUN Jincai WANG Chong and SUN Zhaohui (Institute of Acoustic Engineering Northwestern Polytechnical University Xi’an, 710072) | 1996 | Chinese Journal of Acoustics1996，15，1： | 7 |
| 19 | Property and provenance study of fancy celadon samples excavated from the Noble Burials of the Yue State at Hongshan, China显示文摘The Noble Burials of the Yue State at Hongshan in Wuxi City with many fancy burial objects were excavated by Archaeology Institute of Jiangsu Province and Xishan District Committee for Administration of Cultural Relics of China. It was appraised as one of the ten major archaeological excavations in 2004. Some precious ceramic samples excavated from this site are very important for studying the development history of Chinese ceramics, especially for studying the origin of porcelain. With the cooperation of Archaeology Institute of Nanjing Museum, the ceramic samples excavated from the Noble Burials of the Yue State at Hongshan were collected and systematically analyzed. Compared with the celadon samples produced in Yue-kiln site during later Eastern Han Dynasty (25–220 A.D.), some important topics such as the provenance and properties of the ceramic samples excavated from the Noble Burials of the Yue State at Hongshan were deeply studied. | WU Juan1, WU JunMing1 , LI QiJiang1, ZHANG MaoLin1, LI JiaZhi2, LU XiaoKe2 & DENG ZeQun2 1 Jingdezhen Ceramics Institute, Jingdezhen 333001, China 2 Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China | 2010 | Science China(Technological Sciences)2010，53，2： | 7 |
| 20 | Characterizing Spatial Variability of Soil Textural Fractions and Fractal Parameters Derived from Particle Size Distributions显示文摘Soil particle size distribution(PSD) is a fundamental physical property affecting other soil properties. Characterizing spatial variability of soil texture is very important in environmental research. The objectives of this work were: 1) to partition PSD of 75 soil samples, collected from a flat field in the University of Guilan, Iran, into two scaling domains using a piecewise fractal model to evaluate the relationships between fractal dimensions of scaling domains and soil clay, silt, and sand fractions and 2) to assess the potential of fractal parameters as an index used in a geostatistical approach reflecting the spatial variability of soil texture. Features of PSD of soil samples were studied using fractal geometry, and geostatistical techniques were used to characterize the spatial variability of fractal and soil textural parameters. There were two scaling domains for the PSD of soil samples. The fractal dimensions of these two scaling domains(D_1 and D_2) were then used to characterize different ranges of soil particle sizes and their relationships to the soil textural parameters. There was a positive correlation between D_1 and clay content(R^2= 0.924), a negative correlation between D_1 and silt content(R^2= 0.801), and a negative correlation between D_2 and sand content(R^2= 0.913). The geometric mean diameter of soil particles had a negative correlation with D_1(R^2= 0.569) and D_2(R^2= 0.682). Semivariograms of fractal dimensions and soil textural parameters were calculated and the maps of spatial variation of D_1 and D_2 and soil PSD parameters were provided using ordinary kriging. The results showed that there were also spatial correlations between D_1 and D_2 and particle size fractions.According to the semivariogram models and validation parameters, the fractal parameters had powerful spatial structure and could better describe the spatial variability of soil texture. | Meysam MOHAMMADI Mahmoud SHABANPOUR Mohammad Hossein MOHAMMADI Nasser DAVATGAR | 2019 | Pedosphere2019，29，2： | 7 |
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