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| 1 | Artificially triggered lightning and its characteristic discharge parameters in two severe thunderstorms显示文摘The lightning-induced-damages in the mid-latitude regions are usually caused during severe thunder-storms. But the discharge parameters of natural lightning are difficult to be measured. Five lightning flashes have been artificially triggered with the rocket-wire technique during the passage of two severe thunderstorms. The discharge current and close electric field of return stroke in artificially triggered lightning have been obtained in microsecond time resolution by using current measuring systems and electric field change sensors. The results show that the five triggered lightning flashes include 1 to 10 return strokes, and the average return stroke current is 11.9 kA with a maximum of 21.0 kA and a mini-mum of 6.6 kA, similar to the subsequent return strokes in natural lightning. The half peak width of the current waveform is 39 μs, which is much larger than the usual result. The peak current of stroke Ip (kA) and the neutralized charge Q(C) has a relationship of Ip = 18.5Q0.65. The radiation field of return stroke is 5.9 kV·m-1 and 0.39 kV·m-1 at 60 m and 550 m, respectively. The radiation field decreases as r -1.119 with increase of horizontal distance r from the discharge channel. Based on the well-accepted transmission line model, the speed of return stroke is estimated to be about 1.4×108 m·s-1, with a variation range of (1.1―1.6)×108 m·s-1. Because of the similarities of the triggered lightning and natural lightning, the results in this article can be used in the protection design of natural lightning. | QIE XiuShu ZHANG QiLin ZHOU YunJun FENG GuiLi ZHANG TingLong YANG Jing KONG XiangZhen XIAO QingFu WU ShuJun | 2007 | Science China Earth Sciences2007，50，8： | 16 |
| 2 | Electric field soundings and the charge structure within an isolated thunderstorm显示文摘A strong electric (E) field sounding system was designed to measure the vertical component of the E-fields, temperature, relative humidity and GPS data along the sounding path. In the summer of 2008, in situ measurements of E-field inside the thunderstorms were conducted in Pingliang, Gansu Provience, with the cooperation of an X-band weather radar. One E-field profile inside a thunderstorm was successfully acquired. The sounding data indicated four charge layers along the sounding trajectory, three in-side the thuderstorm and one at its lower boundary. The lower cloud boundary charge layer was negative, acting as a screening layer, and laid between 4.3 to 4.5 km a.s.l. The lower positive charge center (LPCC) existed between 4.5–5.3 km a.s.l. (from 3°C to -2°C); the main negative charge area was present between 5.4–6.6 km a.s.l. (-3°C to -10°C); the upper positive charge layer was between 6.7–7.2 km a.s.l. (-11°C to -14°C). The results support the tripole charge structure inside thunderstorms (above 0°C isotherm altitude), but the LPCC is much larger-than-usual in Chinese inland plateau. | Zhao ZhongKuo Qie XiuShu Zhang TingLong Zhang Tong Zhang HongFa Wang Yong She Yong Sun BaoLai Wang HuaiBin | 2010 | Chinese Science Bulletin2010，55，9： | 8 |
| 3 | A Review of Atmospheric Electricity Research in China显示文摘The importance of atmospheric electricity research has been increasingly recognized in recent decades. Research on atmospheric electricity has been actively conducted since the 1980 s in China. Lightning physics and its effects, as important branches of atmospheric electricity, have received more attention because of their significance both in scientific research and lightning protection applications. This paper reviews atmospheric electricity research based primarily on ground-based field experiments at different regions in China in the last decade. The results described in this review include physics and effects of lightning, rocket-triggered lightning and its physical processes of discharge, thunderstorm electricity on the Tibetan Plateau and its surrounding areas, lightning activity associated with severe convective storms, the effect and response of lightning to climate change, numerical simulation of thunderstorm electrification and lightning discharge, lightning detection and location techniques, and transient luminous events above thunderstorms. | QIE Xiushu ZHANG Yijun YUAN Tie ZHANG Qilin ZHANG Tinglong ZHU Baoyou LU Weitao MA Ming YANG Jing ZHOU Yunjun FENG Guili | 2015 | Advances in Atmospheric Sciences2015，32，2： | 5 |
| 4 | Comparative Analysis of Fractional Vegetation Cover Estimation Based on Multi-sensor Data in a Semi-arid Sandy Area显示文摘The estimation of fractional vegetation cover(FVC) is important for identifying and monitoring desertification, especially in arid and semiarid regions. By using regression and pixel dichotomy models, we present the comparison of Sentinel-2A(S2) multispectral instrument(MSI) and Landsat 8(L8) operational land imager(OLI) data regarding the retrieval of FVC in a semi-arid sandy area(Mu Us Sandland, China, in August 2016). A combination of unmanned aerial vehicle(UAV) high-spatial-resolution images and field plots were used to produce verified data. Based on a normalized difference vegetation index(NDVI) regression model, the results showed that, compared with that of L8, the coefficient of determination(R2) of S2 increased by 26.0%, and the root mean square error(RMSE) and the sum of absolute error(SAE) decreased by 3.0% and 11.4%, respectively. For the ratio vegetation index(RVI) regression model, compared with that of L8, the R2 of S2 increased by 26.0%, and the RMSE and SAE decreased by 8.0% and 20.0%, respectively. When the pixel dichotomy model was used, compared with that of L8, the RMSE of S2 decreased by 21.3%, and the SAE decreased by 26.9%. Overall, S2 performed better than L8 in terms of FVC inversion. Additionally, in this paper, we develop a verified scheme based on UAV data in combination with the object-based classification method. This scheme is feasible and sufficiently robust for building relationships between field data and inversion results from satellite data. Further, the synergy of multi-source sensors(especially UAVs and satellites) is a potential effective way to estimate and evaluate regional ecological environmental parameters(FVC). | LIU Qiuyu ZHANG Tinglong LI Yizhe LI Ying BU Chongfeng ZHANG Qingfeng | 2019 | Chinese Geographical Science2019，29，1： | 4 |
| 5 | Numerical investigation on flow nonuniformity-induced hysteresis in scramjet isolator显示文摘Numerical simulation and theoretical analysis were conducted to study the hysteresis inside scramjet isolator during the reciprocating process of back pressure variation.It is revealed that only a regular reflection is theoretically possible for two leading shocks when the inflow Mach number is greater than 2.0,and no hysteresis can occur in the transition between shock reflection types.Nevertheless,wall suction,gas injection,and background waves cause non-uniformity of the incoming flow and would make hysteresis possible.Besides the classical hysteresis in the transition between shock reflection,new kinds of hysteresis were found in both the deflection angle of separated boundary layer and the location of the shock train.Moreover,the occurrence of hysteresis in the deflection angle of the separated boundary layer is accompanied with the shock reflection hysteresis.In the case with background waves or gas injection,hysteresis in the starting position of leading shock was observed too.As back pressure decreases,the leading shock does not follow the same path as that as the back pressure increases,and it is anchored at the location where the background shock or the injection interacts with the leading shock.It is inferred that,if two strong adverse pressure gradient regions move towards and interact with each other,hysteresis will take place when they start to separate. | Tinglong HUANG Lianjie YUE Shenghu MA Qifan ZHANG Peng ZHANG Xinyu CHANG | 2020 | Chinese Journal of Aeronautics2020，33，12： | 3 |
| 6 | Integrating a model with remote sensing observations by a data assimilation approach to improve the model simulation accuracy of carbon flux and evapotranspiration at two flux sites显示文摘Model simulation and in situ observations are often used to research water and carbon cycles in terrestrial ecosystems, but each of these methods has its own advantages and limitations. Combining these two methods could improve the accuracy of quantifying the dynamics of the water and carbon fluxes of an ecosystem. Data assimilation is an effective means of integrating modeling with in situ observation. In this study, the ensemble Kalman filter(En KF) and the unscented Kalman filter(UKF) algorithms were used to assimilate remotely sensed leaf area index(LAI) data with the Biome-BGC model to simulate water and carbon fluxes at the Harvard Forest Environmental Monitoring Site(EMS) and the Dinghushan site. After MODIS LAI data from 2000–2004 were assimilated into the improved Biome-BGC model using the En KF algorithm at the Harvard Forest site, the R2 between the simulated and observed results for NEE and evapotranspiration increased by 7.8% and 4.7%, respectively. In addition, the sum of the absolute error(SAE) and the root mean square error(RMSE) of NEE decreased by an average of 21.9% and 26.3%, and the SAE and RMSE of evapotranspiration decreased by 24.5% and 25.5%, respectively. MODIS LAI data of 2003 were assimilated into the Biome-BGC model for the Dinghushan site, and the R2 values between the simulated and observed results for NEE and evapotranspiration were increased by 6.7% and 17.3%, respectively. In addition, the SAE values of NEE and ET were decreased by 11.3% and 30.7%, respectively, and the RMSE values of NEE and ET decreased by 10.1% and 30.9%, respectively. These results demonstrate that the accuracy of carbon and water flux simulations can be effectively improved when remotely sensed LAI data are properly integrated with ecosystem models through a data assimilation approach. | ZHANG TingLong SUN Rui PENG ChangHui ZHOU GuoYi WANG ChunLing ZHU QiuAn YANG YanZheng | 2016 | Science China Earth Sciences2016，59，2： | 3 |
| 7 | Electrical characteristics of thunderstorms in different plateau regions of China显示文摘 | Xiushu Qie Tinglong Zhang Guangshu Zhang Tong Zhang Xiangzhen Kong | 2008 | Atmospheric Research2008，，2： | 2 |
| 8 | An Acquisition Policy for a Multi-Supplier System with a Finite-Time Horizon显示文摘 | Dai Tinglong Qi Xiangtong | 2007 | Computers & Operations Research2007，34，： | 1 |
| 9 | A better carbon-water flux simulation in multiple vegetation types by data assimilation显示文摘Background:The accurate estimation of carbon-water flux is critical for understanding the carbon and water cycles of terrestrial ecosystems and further mitigating climate change.Model simulations and observations have been widely used to research water and carbon cycles of terrestrial ecosystems.Given the advantages and limitations of each method,combining simulations and observations through a data assimilation technique has been proven to be highly promising for improving carbon-water flux simulation.However,to the best of our knowledge,few studies have accomplished both parameter optimization and the updating of model state variables through data assimilation for carbon-water flux simulation in multiple vegetation types.And little is known about the variation of the performance of data assimilation for carbon-water flux simulation in different vegetation types.Methods:In this study,we assimilated leaf area index(LAI)time-series observations into a biogeochemical model(Biome-BGC)using different assimilation algorithms(ensemble Kalman filter algorithm(EnKF)and unscented Kalman filter(UKF))in different vegetation types(deciduous broad-leaved forest(DBF),evergreen broad-leaved forest(EBF)and grassland(GL))to simulate carbon-water flux.Results:The validation of the results against the eddy covariance measurements indicated that,overall,compared with the original simulation,assimilating the LAI into the Biome-BGC model improved the carbon-water flux simulations(R^(2)increased by 35%,root mean square error decreased by 10%;the sum of the absolute error decreased by 8%)but more significantly,improved the water flux simulations(R^(2)increased by 31%,root mean square error decreased by 18%;the sum of the absolute error decreased by 16%).Among the different forest types,the data assimilation techniques(both EnKF and UKF)achieved the best performance towards carbon-water flux in EBF(R^(2)increased by 44%,root mean square error decreased by 24%;the sum of the absolute error decreased by 28%),and the performances of EnKF and UKF showed slightly different when simulating carbon fluxes.Conclusion:We suggest that to reduce the uncertainty in global carbon-water flux quantification,forthcoming data assimilation treatment should consider the vegetation types where the data assimilation experiments are carried out,the simulated objectives and the assimilation algorithms. | Qiuyu Liu Tinglong Zhang Mingxi Du Huanlin Gao Qingfeng Zhang Rui Sun | 2022 | Forest Ecosystems2022，9，1： | 1 |
| 10 | Characteristics of thunderstorms and lightning flashes in the Chinese inland plateau显示文摘The electrical characteristics of thunderstorms in three different altitude regions of the Chinese inland plateau have been analyzed in this paper. The results show, according to the polarity of the surface electric (E) field, that the thunderstorms can be divided into two categories in the study regions: one showing the normal tripole electrical charge structure (normal-type), and the other showing the special tripole charge structure with a larger-than-usual lower positive charge center (LPCC) at the base of thunderstorm (special-type), where the induced surface E field is controlled by the LPCC when a thunderstorm is overhead. We find that the two types of thunderstorms have different occurrences in different regions, and the percentage of special-type thunderstorms increases with the altitude. On the whole, the flash rate of thunderstorms is quite low, and the mean value is about 1-3 fl/min, while the flash rate of special-type is slightly greater than that of the normal-type thunderstorm. The statistical results of cloud-to-ground flash (CG) numbers indicate that the ratio of +CG flash increases with the altitude, with the value about 14.7 percent through 25.4 percent. | TingLong Zhang Tong Zhang Yang Zhao XiangZhen Kong YanHui Wang | 2010 | Research in Cold and Arid Regions2010，2，3： | 1 |
| 11 | An integrated vendor-managed inventory model for a two-echelon system with order cost reduction 显示文摘 | Zhang Tinglong Liang Liang Yu Yugang | 2007 | International Journal of Production Economics2007，109，12： | 1 |
| 12 | An acquisition policy for a multi-supplier system with a finite-time horizon 显示文摘 | Dai Tinglong Qi Xiangton | 2007 | Computers and Operations Research2007，34，： | 1 |
| 13 | Pure Detail Feature Extraction Network for Visible-Infrared Re-Identification显示文摘Cross-modality pedestrian re-identification has important appli-cations in the field of surveillance.Due to variations in posture,camera per-spective,and camera modality,some salient pedestrian features are difficult to provide effective retrieval cues.Therefore,it becomes a challenge to design an effective strategy to extract more discriminative pedestrian detail.Although many effective methods for detailed feature extraction are proposed,there are still some shortcomings in filtering background and modality noise.To further purify the features,a pure detail feature extraction network(PDFENet)is proposed for VI-ReID.PDFENet includes three modules,adaptive detail mask generation module(ADMG),inter-detail interaction module(IDI)and cross-modality cross-entropy(CMCE).ADMG and IDI use human joints and their semantic associations to suppress background noise in features.CMCE guides the model to ignore modality noise by generating modality-shared feature labels.Specifically,ADMG generates masks for pedestrian details based on pose estimation.Masks are used to suppress background information and enhance pedestrian detail information.Besides,IDI mines the semantic relations among details to further refine the features.Finally,CMCE cross-combines classifiers and features to generate modality-shared feature labels to guide model training.Extensive ablation experiments as well as visualization results have demonstrated the effectiveness of PDFENet in eliminating background and modality noise.In addition,comparison experi-ments in two publicly available datasets also show the competitiveness of our approach. | Jiaao Cui Sixian Chan Pan Mu Tinglong Tang Xiaolong Zhou | 2023 | Intelligent Automation & Soft Computing2023，37，8： | 0 |
| 14 | Association Strategy Graph Convolutional Neural Network for Human Skeletal Behavior Recognition显示文摘Aiming at the problem that the joint point partition strategy expresses the important information of the human body in the human body behavior recognition of bones cannot fully express the behavior,anRCTR-GCNhuman bone behavior recognition model of the correlation strategy is proposed.First,by adding an association strategy of a refined graph convolutional network model(CTR-GCN)of the smart channel topology,it can dynamically learn different topological structures and efficiently amplify the characteristics of the connection points in different channels while improving the key joint points of associated characteristics.Then,the network model redefines each channel by learning a shared topology and uses a specific channel relationship to unify the model through theoretical analysis;finally,redefining the model structure effectively reflects the associated information of local nodeswithin the channel.Action recognition has stronger aggregation capabilities.The results show that the recognition accuracy in the commonly used NTU RGB+D and NW-UCLA datasets reaches 93.6%(X-View),97.6%(XSub),and 97.2%,respectively.The experimental results show that the accuracy rate is improved. | Tinglong Liu | 2022 | 国际计算机前沿大会会议论文集2022，，1： | 0 |
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