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| 1 | Metallogenic Epoch and Ore-forming Environment of the Lamasu Skarn-porphyritic Cu-Zn deposit,western Tianshan,Xinjiang,NW China显示文摘花岗石的岩石,广泛地在 Lamasu 铜矿石区域发展了,西方的 Tianshan 在 390.5 | ZHANG Zuoheng WANG Zhiliang WANG Longsheng ZUO Guochao | 2008 | Acta Geologica Sinica(English Edition)2008，82，4： | 21 |
| 2 | Kiwifruit recognition at nighttime using artificial lighting based on machine vision显示文摘Most researches involved so far in kiwifruit harvesting robot suggest the scenario of harvesting in daytime for taking advantage of sunlight.A robot operating at nighttime can overcome the problem of low work efficiency and would help to minimize fruit damage.In addition,artificial lights can be used to ensure constant illumination instead of the variable natural sunlight for image capturing.This paper aims to study the kiwifruit recognition at nighttime using artificial lighting based on machine vision.Firstly,an RGB camera was placed underneath the canopy so that clusters of kiwifruits could be included in the images.Next,the images were segmented using an R-G color model.Finally,a group of image processing conventional methods,such as Canny operator were applied to detect the fruits.The image processing results showed that this capturing method could reduce the background noise and overcome any target overlapping.The experimental results showed that the optimal artificial lighting ranged approximately between 30-50 lx.The developed algorithm detected 88.3%of the fruits successfully. | Fu Longsheng Wang Bin Cui Yongjie Su Shuai Yoshinori Gejima Taiichi Kobayashi | 2015 | International Journal of Agricultural and Biological Engineering2015，8，4： | 14 |
| 3 | Thermal decomposition and oxidation of bastnaesite concentrate in inert and oxidative atmosphere显示文摘To clearly elucidate the oxidative roasting behaviors of the bastnaesite, the thermal decomposition and oxidation of the bastnaesite concentrate in inert and oxidative atmosphere have been investigated in detail. Experimental data indicated that the initial decomposition temperature of the concentrate under N_2 atmosphere is 150 ℃ higher than that under O_2 atmosphere,most likely because the oxidation of the cerium induces the decomposition of the concentrate. For the roasted samples under N_2 atmosphere at500 ℃ and above,the oxidation efficiency of the cerium is 19.8%-26.8% because of the fact that rareearth fluorocarbonate is first decomposed to form rare-earth oxyfluoride and CO_2, and the cerium oxyfluoride is then partially oxidized by the CO_2 gas. The rest cerium in these samples can be further oxidized in air at room temperature, with the oxidation efficiency of the cerium gradually increasing to above 80% in 7 d. This can be attributed to the obvious changes in the inner morphology of the roasted samples under N_2 atmosphere at high temperatures, which largely induce the diffusion of the air and improves the oxidation activity of CeOF, and further induces the oxidation of CeOF by the air. XRD and XPS techniques were used to further verify the significant differences in the thermal decomposition behaviors of the bastnaesite concentrate under N_2 and O_2 atmosphere. Moreover, no oxidation of Pr^(3+) to Pr^(4+) in the roasted samples under both N_2 and O_2 atmosphere is observed. This gives an overall understanding of the oxidative roasting of the bastnaesite concentrate without additives. | Longsheng Zhao Liangshi Wang Genghong Shuai Zhiqi Long Dali Cui Xiaowei Huang | 2018 | Journal of Rare Earths2018，36，7： | 10 |
| 4 | Adaptive Robust Control for a Class of Uncertain MIMO Non-affine Nonlinear Systems显示文摘In this paper, the adaptive robust tracking control scheme is proposed for a class of multi-input and multioutput(MIMO) non-affine systems with uncertain structure and parameters, unknown control direction and unknown external disturbance based on backstepping technique. The MIMO nonaffine system is first transformed into a time-varying system with strict feedback structure using the mean value theorem,and then the bounded time-varying parameters are estimated by adaptive algorithms with projection. To handle the possible'controller singularity' problem caused by unknown control direction, a Nussbaum function is employed, and the dynamic surface control(DSC) method is applied to solve the problem of'explosion of complexity' in backstepping control. It is proved that the proposed control scheme can guarantee that all signals of the closed-loop system are bounded through Lyapunov stability theorem and decoupled backstepping method. Simulation results are presented to illustrate the effectiveness of the proposed control scheme. | Longsheng Chen Qi Wang | 2016 | IEEE/CAA Journal of Automatica Sinica2016，3，1： | 9 |
| 5 | Experimental characteristics of oblique shock train upstream propagation显示文摘The structure and dynamics of an oblique shock train in a duct model are investigated experimentally in a hypersonic wind tunnel.Measurements of the pressure distribution in front of and across the oblique shock train have been taken and the dynamics of upstream propagation of the oblique shock train have been analyzed from the synchronized schlieren imaging with the dynamic pressure measurements.The formation and propagation of the oblique shock train are initiated by the throttling device at the downstream end of the duct model.Multiple reflected shocks,expansion fans and separated flow bubbles exist in the unthrottled flow,causing three adversepressure-gradient phases and three favorable-pressure-gradient phases upstream the oblique shock train.The leading edge of the oblique shock train propagates upstream,and translates to be asymmetric with the increase of backpressure.The upstream propagation rate of the oblique shock train increases rapidly when the leading edge of the oblique shock train encounters the separation bubble near the shock reflection point and the adverse-pressure-gradient phase,while the oblique shock train slow movement when the leading edge of the oblique shock train is in the favorablepressure-gradient phase for unthrottled flow.The asymmetric flow pattern and oscillatory nature of the oblique shock train are observed throughout the whole upstream propagation process. | Wang Chengpeng Xue Longsheng Tian Xuang | 2017 | Chinese Journal of Aeronautics2017，30，2： | 7 |
| 6 | 0.75 Gbit/s high-speed classical key distribution with mode-shift keying chaos synchronization of Fabry–Perot lasers显示文摘High-speed physical key distribution is diligently pursued for secure communication.In this paper,we propose and experimentally demonstrate a scheme of high-speed key distribution using mode-shift keying chaos synchronization between two multi-longitudinal-mode Fabry–Perot lasers commonly driven by a super-luminescent diode.Legitimate users dynamically select one of the longitudinal modes according to private control codes to achieve mode-shift keying chaos synchronization.The two remote chaotic light waveforms are quantized to generate two raw random bit streams,and then those bits corresponding to chaos synchronization are sifted as shared keys by comparing the control codes.In this method,the transition time,i.e.,the chaos synchronization recovery time is determined by the rising time of the control codes rather than the laser transition response time,so the key distribution rate is improved greatly.Our experiment achieved a 0.75-Gbit/s key distribution rate with a bit error rate of 3.8×10^(−3)over 160-km fiber transmission with dispersion compensation.The entropy rate of the laser chaos is evaluated as 16 Gbit/s,which determines the ultimate final key rate together with the key generation ratio.It is therefore believed that the method pays a way for Gbit/s physical key distribution. | Hua Gao Anbang Wang Longsheng Wang Zhiwei Jia Yuanyuan Guo Zhensen Gao Lianshan Yan Yuwen Qin Yuncai Wang | 2021 | Light(Science & Applications)2021，10，9： | 7 |
| 7 | A nontrivial factor in determining current distribution in an ac HTS cable-proximity effect显示文摘A superconductor has zero resistance at the superconducting state. This unique property creates many exceptional phenomena, of which some are known and the others are not. Our experiments with multilayer high temperature superconductor (HTS) cable samples revealed a new phenomenon that alternating current had a tendency to flow in the inner and outer layers of the cables. We attribute the cause of this phenomenon to the electromagnetic interaction in an infinite electrical conductivity medium and term it 'super-proximity-effect'. This effect will greatly affect the performance of a multilayer superconducting cable and other superconducting devices which are involved with alternating current transportation. | XIN Ying,GONG WeiZhi & ZHANG JingYin Innopower Superconductor Cable Co.,Ltd.,7 E.Rongchang Rd.,Longsheng Industrial Park,Beijing Economic & Technological Development Area,Beijing 100176,China | 2010 | Science China(Technological Sciences)2010，53，4： | 6 |
| 8 | Design and simulation of an integrated end-effector for picking kiwifruit by robot显示文摘The harvesting of fresh kiwifruit is a labor-intensive operation that accounts for more than 25%of annual production costs.Mechanized harvesting technologies are thus being developed to reduce labor requirements for harvesting kiwifruit.To improve the efficiency of a harvesting robot for picking kiwifruit,we designed an end-effector,which we report herein along with the results of tests to verify its operation.By using the established method of automated picking discussed in the literature and which is based on the characteristics of kiwifruit,we propose an automated method to pick kiwifruit that consists of separating the fruit from its stem on the tree.This method is experimentally verified by using it to pick clustered kiwifruit in a scaffolding canopy cultivation.In the experiment,the end-effector approaches a fruit from below and then envelops and grabs it with two bionic fingers.The fingers are then bent to separate the fruit from its stem.The grabbing,picking,and unloading processes are integrated,with automated picking and unloading performed using a connecting rod linkage following a trajectory model.The trajectory was analyzed and validated by using a simulation implemented in the software Automatic Dynamic Analysis of Mechanical Systems(ADAMS).In addition,a prototype of an end-effector was constructed,and its bionic fingers were equipped with fiber sensors to detect the best position for grabbing the kiwifruit and pressure sensors to ensure that the damage threshold was respected while picking.Tolerances for size and shape were incorporated by following a trajectory groove from grabbing and picking to unloading.The end-effector separates clustered kiwifruit and automatically grabs individual fruits.It takes on average 4–5 s to pick a single fruit,with a successful picking rate of 94.2%in an orchard test featuring 240 samples.This study shows the grabbing–picking–unloading robotic end-effector has significant potential to facilitate the harvesting of kiwifruit. | Longtao Mu Gongpei Cui Yadong Liu Yongjie Cui Longsheng Fu Yoshinori Gejima | 2020 | Information Processing in Agriculture2020，7，1： | 6 |
| 9 | Track of Grain in Forced Vortex with Horizontal Axis显示文摘TrackofGraininForcedVortexwithHorizontalAxisPengLongsheng(Dept.ofHyd.Eng.)AbstractAmathematicalmethodtofindtrackofgraininthe... | Peng Longsheng (Dept.of Hyd.Eng.) | 1997 | 太原理工大学学报1997，28，S1： | 5 |
| 10 | 日本高灌蓝莓采收最适线锯振动速度(摘选) | Longsheng Fu Hiroshi Okamoto Yoichiro Hoshino Takashi Kataoka Youichi Shibata | 2012 | 农业工程2012，2，2： | 5 |
| 11 | Mechanized technologies for scaffolding cultivation in the kiwifruit industry:A review显示文摘The success of organic and green agricultural fruit production depends on quality and cost.As the kiwifruit industry becomes ever more commercialized,it is in the interests of the industry to mechanize production,which can promote industrialization and improve industrial value and market prospects.Currently,New Zealand,Italy,Chile,and China carry out research into the mechanism of kiwifruit production.This review describes in detail the current state of the art of pollination,harvesting and grading equipment,including detection and identification,non-destructive end effector,harvesting robots and grading devices.Process technologies that include artificial pollination,harvest mechanization,grading and standardization of production problems are analysed and compared.These problems directly affect the quality of kiwifruit products.Finally,to solve the various problems that the kiwifruit industry experiences,it is necessary to accelerate the development of mechanized kiwifruit production,realize the mechanization of information acquisition and standardization in order to advance precision agriculture and agricultural wisdom for the future.Mechanization of the kiwifruit industry must adapt to adjustments in how China’s economic structure develops. | Longtao Mu Haozhou Liu Yongjie Cui Longsheng Fu Yoshinori Gejima | 2018 | Information Processing in Agriculture2018，5，4： | 5 |
| 12 | Aqueous stability of rare earth and thorium elements during hydrochloric acid leaching of roasted bastnaesite显示文摘In order to study the aqueous stability of rare earth and thorium elements and the reaction mechanism of hydrochloric acid leaching of roasted bastnaesite,E_h-pH diagrams for La-,Nd-,Ce-,Th-(Cl)-(F)-H_2 O systems at 20 ℃ were depicted using HSC Chemistry 6.0 software. E_h-pH diagrams of La-, Ce-,Nd-and Th-Cl-H_2 O systems show that trivalent rare earth would be leached into solution by adjusting the acidity of the leaching solution, while tetravalent cerium and thorium would be remained in the leaching residue. And in the case that the pH value of the leaching solution is lower than 2, tetravalent cerium would be partially reduced by chlorine ions(Cl^-), which is well agreed with the industrial production. It can be inferred from E_h-pH diagrams for the systems La-, Nd-,Ce-, Th-F-H_2 O that the leached trivalent rare earth ions(RE^(3+)) and tetravalent thorium ions(Th^(4+)) are preferentially combined with fluorine ions(F) to form sediment during non-reductive acid leaching of roasted bastnaesite. However,when controlling the pH value of the leaching solution below 0, fluorine and tetravalent cerium in the roasted bastnaesite would be leached out in the form of soluble [CeF_3]^+ complex. That means the precipitation of REF_3 and ThF_4·2.5 H_2 O can be avoided in the leaching step. According to E_h-pH diagrams for the system Ce-F-Cl-H_2 O, [CeF_3]^+ in the leaching solution would be reduced to CeF3 precipitate in the presence of Cl^-, that is to say, tetravalent cerium and fluorine would be firstly leached out to form[CeF_3]^+,which would then be reduced to CeF3 precipitate by Cl^-in the hydrochloric acid leaching process of roasted bastnaesite. | Genghong Shuai Longsheng Zhao Liangshi Wang Zhiqi Long Dali Cui | 2017 | Journal of Rare Earths2017，35，12： | 4 |
| 13 | Partial functional linear quantile regression显示文摘This paper studies estimation in partial functional linear quantile regression in which the dependent variable is related to both a vector of finite length and a function-valued random variable as predictor variables.The slope function is estimated by the functional principal component basis. The asymptotic distribution of the estimator of the vector of slope parameters is derived and the global convergence rate of the quantile estimator of unknown slope function is established under suitable norm. It is showed that this rate is optimal in a minimax sense under some smoothness assumptions on the covariance kernel of the covariate and the slope function. The convergence rate of the mean squared prediction error for the proposed estimators is also established. Finite sample properties of our procedures are studied through Monte Carlo simulations. A real data example about Berkeley growth data is used to illustrate our proposed methodology. | TANG QingGuo CHENG LongSheng | 2014 | Science China Mathematics2014，57，12： | 3 |
| 14 | Extraction mechanism and separation behaviors of low-concentration Nd^(3+) and Al^(3+) in P507-H_(2)SO_(4) system显示文摘In order to clarify the solvent extraction and separation behaviors of rare earths and impurity of Al during the extraction and enrichment of low-concentration leach solution of ion-adsorption rare earth ore,the extraction mechanism and separation behaviors of Nd^(3+)and Al^(3+)in the Nd_(2)(SO_(4))_(3)-AI_(2)(SO_(4))_(3) mixed solution using P507 were studied in this work.The extraction of Nd^(3+)and Al^(3+)follows the cation exchange mechanism.With the increase of the equilibrium pH,β_(Nd/Al) in the extraction of the Nd_(2)(SO_(4))_(3)-Al_(2)(SO_(4))_(3) mixed solution using P507 is always higher than that in the extraction of single Nd_(2)(SO_(4))_(3) and Al_(2)(SO_(4))_(3) solutions.It can be attributed to the fact that the extraction of Nd^(3+)using P507 is much faster than that of Al^(3+),and Al^(3+)is more prone to be hydrolyzed at lower pH.β_(Nd/Al) in the extraction of the Nd_(2)(SO_(4))_(3)-Al_(2)(SO_(4))_(3) mixed solution decreases gradually with the increase of mixing time within the equilibrium pH range of 1.5-1.9.The extraction of Nd^(3+)using P507 is much faster than that of Al^(3+),but the stability of Al^(3+)-Ioaded organic phase is better than that of Nd^(3+)-loaded organic phase,thus Nd^(3+)in the Nd^(3+)-loaded organic phase is gradually replaced by Al^(3+)in the aqueous phase with the increase of mixing time. | Hongyuan Zhang Longsheng Zhao Xudong Zheng Depeng Liu Zongyu Feng Yongqi Zhang Xiaowei Huang | 2022 | Journal of Rare Earths2022，40，6： | 3 |
| 15 | Numerical Research on Inlet Total Pressure Distortion in a Transonic Compressor with Non-Axisymmetric Stator Clearance显示文摘Inlet total pressure distortion has great adverse effects on the aero-engine performance. The distorted flow passes through the compressor and becomes non-uniform in the downstream blade rows. Different from previous studies based on the assumption of circumferential uniformity, this study aims to improve circumferential non-uniform flow with the non-axisymmetric structure. Non-axisymmetric stator clearance was adopted to resolve the effects of non-uniform flow caused by inlet total pressure distortion in this paper. The 9 stators with tip clearance were installed in the distorted region and the flow field structure and performance under different operating conditions was studied. The study finds that the non-axisymmetric compressor with 9 tip clearance stators can ensure compressor efficiency while improving compressor stability margin. What’s more, the separation range and strength in the distorted region can be reduced significantly and the anti-distortion capability of compressor can be enhanced. | XU Wenfeng SUN Peng YANG Guogang HUANG Longsheng FU Wenguang | 2020 | Journal of Thermal Science2020，29，4： | 3 |
| 16 | Optical frequency divider with division uncertainty at the 10^(-21) level显示文摘Optical clocks with unprecedented accuracy of 10^(-18) promise innovations in many research areas.heir applications rely to a large extent on the ability of precisely converting the frequency from one optical clock to another,or particularly to the frequencies in the iber telecom band for long-distance transmission.his report demonstrates a low-noise,high-precision optical frequency divider,which realizes accurate optical frequency conversion and enables precise measurement of optical frequency ratios.By measuring against the frequency ratio between the fundamental and the second harmonic of a 1064-nm laser instead of a second copy of the same system,we demonstrate that the optical frequency divider has a fractional frequency division instability of 6×10^(-19) at 1 s and a fractional frequency division uncertainty of 1.4×10^(-21).he remarkable numbers can support frequency division of the best optical clocks in the world without frequency-conversion-caused degradation of their performance. | Yuan Yao Yanyi Jiang Hongfu Yu Zhiyi Bi Longsheng Ma | 2016 | National Science Review2016，3，4： | 3 |
| 17 | B-spline estimation for varying coefficient regression with spatial data显示文摘This paper considers a nonparametric varying coefficient regression with spatial data. A global smoothing procedure is developed by using B-spline function approximations for estimating the coefficient functions. Under mild regularity assumptions,the global convergence rates of the B-spline estimators of the unknown coefficient functions are established. Asymptotic results show that our B-spline estimators achieve the optimal convergence rate. The asymptotic distributions of the B-spline estimators of the unknown coefficient functions are also derived. A procedure for selecting smoothing parameters is given. Finite sample properties of our procedures are studied through Monte Carlo simulations. Application of the proposed method is demonstrated by examining voting behaviors across US counties in the 1980 presidential election. | TANG QingGuo CHENG LongSheng | 2009 | Science China Mathematics2009，52，11： | 3 |
| 18 | Progress and trend of narrow-linewidth lasers显示文摘High frequency stability, narrow-linewidth lasers have been long dreamed of since the invention of the laser. They have recently developed dramatically due to the advent of optical clocks. State-of-the-art narrow-linewidth lasers have been constructed by using the Pound-Drever-Hall (PDH) technique to lock the laser frequencies to the resonance of ultra-stable external optical cavities with high finesse. This paper introduces the developments of narrow-linewidth lasers, with a focus on the improvements of length stability of optical reference cavities, including optical cavity designs of vibration insensitivity and low thermal noise. Future trends and alternative methods for narrow-linewidth lasers are also discussed. | CHEN HaiQin JIANG YanYi BI ZhiYi MA LongSheng | 2013 | Science China(Technological Sciences)2013，56，7： | 3 |
| 19 | LOW-POWER LVDS I/O INTERFACE FOR ABOVE 2GB/S-PER-PIN OPERATION显示文摘Low Voltage Differential Signaling (LVDS) has become a popular choice for high-speed serial links to conquer the bandwidth bottleneck of intra-chip data transmission. This paper presents the design and the implementation of LVDS Input/Output (I/O) interface circuits in a standard 0.18 μm CMOS technology using thick gate oxide devices (3.3 V), fully compatible with LVDS standard. In the proposed transmitter, a novel Common-Mode FeedBack (CMFB)circuit is utilized to keep the common-mode output voltage stable over Process, supply Voltage and Temperature (PVT) variations. Because there are no area greedy resistors in the CMFB circuitry, the disadvantage of large die area in existing transmitter structures is avoided. To obtain sufficient gain, the receiver consists of three am- plifying stages: a voltage amplifying stage, a transconductance amplifying stage, and a transimpedance amplifying stage. And to exclude inner nodes with high RC time constant, shunt-shunt negative feedback is introduced in the receiver. A novel active inductor shunt peaking structure is used in the receiver to fulfill the stringent requirements of high speed and wide Common-Mode Input Region (CMIR) without voltage gain, power dissipation and silicon area penalty. Simulation results show that data rates of 2 Gbps and 2.5 Gbps are achieved for the transmitter and receiver with power con- sumption of 13.2 mW and 8.3 mW respectively. | Wang Xihu Wu Longsheng Liu Youbao | 2009 | Journal of Electronics(China)2009，26，4： | 3 |
| 20 | The Combined Effect of Plastic Particles Size and Concentration on Rotifers’ (Brachionus plicatilis) Performance显示文摘The presence of microplastics in aquatic ecosystems is of increasing global concern.Nano-sized plastics,in particular,can penetrate the cell membrane and cause biological death.Our study evaluated the combined impacts of several polystyrene mi-crospheres’sizes and nominal concentrations on the overall performance changes of Brachionus plicatilis.Experimental animals were exposed to three microplastic sizes(0.08,0.5 and 6μm)and five nominal concentrations(0,0.5,2,8,32μg mL−1)for 20 d.Our results showed that the toxicological effect of particle size on rotifers did not significantly depend on the nominal concentration.The interaction between the nominal concentration and size occurred only for body length and lorica width.Specifically,high nominal concentrations of microplastics that were close to nanometer size significantly impaired the overall vitality of rotifers,embodied in shortage of body type,delay in the arrival of maturity,reduction in the cumulative number of neonates,and the advance of the death process.In comparison,fair-sized size(0.5 and 6μm)displayed non-significant damage except for individual groups.Most notably,the net reproductive yield was only a third of what it was in the original environment,implying that there was not much fertility left.Besides,with the development of rotifers,the adverse effects of polystyrene microsphere drive had become more and more serious. | SUI Yanming WANG Senyang MOHSEN Mohamed ZHANG Longsheng SHEN Mengyan LIU Zhiquan NGUYEN Haidang ZHANG Shengmao LI Kaixing LV Linlan DONG Xuexing | 2022 | Journal of Ocean University of China2022，21，2： | 3 |
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