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1Inkjet printing for flexible electronics:Materials,processes and equipments显示文摘Inkjet printing, known as digital writing technique, can directly deposit functional materials to form pattern onto substrate. This paper provides an overview of inkjet printing technologies for flexible electronics. Firstly, we highlight materials challenges in implementing flexible devices into practical application, especially for inkjet printing process. Then the micro/nano-patterning technologies of inkjet printing are discussed, including conventional inkjet printing techniques and electrohydrodynamic printing techniques. Thirdly, the related equipments on inkjet printing are shown. Finally, challenges for its future development are also discussed. The main purpose of the work is to condense the basic knowledge and highlight the challenges associated with the burgeoning and exciting field of inkjet printing for flexible electronics.YIN ZhouPing HUANG YongAn BU NingBin WANG XiaoMei XIONG YouLun 2010Chinese Science Bulletin2010,55,30:25
2A blow-up criterion for classical solutions to the compressible Navier-Stokes equations显示文摘In this paper, we obtain a blow-up criterion for classical solutions to the 3-D compressible Navier-Stokes equations just in terms of the gradient of the velocity, analogous to the Beal-Kato-Majda criterion for the ideal incompressible flow. In addition, the initial vacuum is allowed in our case.HUANG XiangDi 1 & XIN ZhouPing 2, 1 Department of Mathematics, University of Science and Technology of China, Hefei 230026, China 2 Department of Mathematics, The Chinese University of Hong Kong, Hong Kong, China 2010Science China Mathematics2010,53,3:13
3Individual idea about the micro-invasive aspiration and drainage of intracranial hematoma显示文摘AIM: This study aimed to expound the individual idea of micro-invasive surgery from pre-operative preparation, intra-operative processing and post-operative management. METHODS: Pre-operative preparation was improved by analyzing pathological factors and hematoma property, and considering patients' age, basic disease, blood pressure control, with persistent haemorrhagia/rehaemorrhagia or not, operative occasion choice, positioning and other procedures. In the surgery, positioner was used. Initial aspiration volume was cautiously controlled. After operation, vital signs of patients were kept stable by cautiously using hematoma liquefacient and combining with free radical scavenger. RESULTS: The core content of individual micro-invasive surgery was mainly to relieve intracranial pressure. Under the condition of sufficient pre-operative preparation known by patients' family members, precise positioning was determined and individual therapeutic regimen was made. Meanwhile, caution should be taken in hematoma aspiration. Liquefaction and drainage should be paid more attention, and complications were processed actively. CONCLUSION: During the process of micro-invasive evacuation of intracranial hematoma for treating cerebral hemorrhage, attention should be paid to analyzing cerebral hematoma etiology and pathophysiological mechanism, and individual idea should be considered in surgical treatment aiming at patients' concrete disease condition.Zhouping Tang Feng Xu Xingyong Chen Xiangwu Meng Wei Hu Suiqiang Zhu Wei Wang 2007Neural Regeneration Research2007,2,12:12
4Robust adaptive control for a nonholonomic mobile robot with unknown parameters显示文摘A robust adaptive controller for a nonholonomic mobile robot with unknown kinematic and dynamic parameters is proposed.A kinematic controller whose output is the input of the relevant dynamic controller is provided by using the concept of backstepping.An adaptive algorithm is developed in the kinematic controller to approximate the unknown kinematic parameters,and a simple single-layer neural network is used to express the highly nonlinear robot dynamics in terms of the known and unknown parameters.In order to attenuate the effects of the uncertainties and disturbances on tracking performance,a sliding mode control term is added to the dynamic controller.In the deterministic design of feedback controllers for the uncertain dynamic systems,upper bounds on the norm of the uncertainties are an important clue to guarantee the stability of the closed-loop system.However,sometimes these upper bounds may not be easily obtained because of the complexity of the structure of the uncertainties.Thereby,simple adaptation laws are proposed to approximate upper bounds on the norm of the uncertainties to address this problem.The stability of the proposed control system is shown through the Lyapunov method.Lastly,a design example for a mobile robot with two actuated wheels is provided and the feasibility of the controller is demonstrated by numerical simulations.Jinbo WU Guohua XU Zhouping YIN 2009控制理论与应用(英文版)2009,7,2:9
5Dynamics of ecosystem carbon stocks during vegetation restoration on the Loess Plateau of China显示文摘In the last few decades, the Loess Plateau had experienced an extensive vegetation restoration to reduce soil erosion and to improve the degraded ecosystems. However, the dynamics of ecosystem carbon stocks with vegetation restoration in this region are poorly understood. This study examined the changes of carbon stocks in mineral soil(0–100 cm), plant biomass and the ecosystem(plant and soil) following vegetation restoration with different models and ages. Our results indicated that cultivated land returned to native vegetation(natural restoration) or artificial forest increased ecosystem carbon sequestration. Tree plantation sequestered more carbon than natural vegetation succession over decades scale due to the rapid increase in biomass carbon pool. Restoration ages had different effects on the dynamics of biomass and soil carbon stocks. Biomass carbon stocks increased with vegetation restoration age, while the dynamics of soil carbon stocks were affected by sampling depth. Ecosystem carbon stocks consistently increased after tree plantation regardless of the soil depth; but an initial decrease and then increase trend was observed in natural restoration chronosequences with the soil sampling depth of 0–100 cm. Moreover, there was a time lag of about 15–30 years between biomass production and soil carbon sequestration in 0–100 cm, which indicated a long-term effect of vegetation restoration on deeper soil carbon sequestration.WANG Kaibo DENG Lei REN Zongping SHI Weiyu CHEN Yiping SHANG-GUAN Zhouping 2016Journal of Arid Land2016,8,2:7
6HIGH QUALITY DEVELOPMENTAL APPROACH FOR SOIL AND WATER CONSERVATION AND ECOLOGICAL PROTECTION ON THE LOESS PLATEAU显示文摘The Loess Plateau is the core area in the Yellow River basin for implementing environmental protection and high-quality development strategies. A series of ecological projects has implemented aimed at soil and water conservation and ecological management on the Loess Plateau over the past 70 years. The effects of the ecological projects are apparent mainly through a marked increase in vegetation cover, controlled soil erosion and reduced flow of sediment into the Yellow River, continual optimization of the industrial structure and increased production from arable land, poverty alleviation and greater prosperity, and optimal allocation of space for biological organisms.Major problems have also been analyzed in ecological management including the fragile ecosystem of the region, maintaining the stability of vegetation,lower agricultural productivity and continued risk from natural disasters. Some suitable schemes and models have been developed for the coordinated development of the region through research and demonstration, striking the optimum balance between rural industry and ecology, and increased regionalcapacity to supply high-quality ecological products. Countermeasures to address the problems are suggested to guide ecological management and high-quality development in the future.Lei DENG Zhouping SHANGGUAN 2021Frontiers of Agricultural Science and Engineering2021,8,4:7
7Driving force planning in shield tunneling based on Markov decision processes显示文摘In shield tunneling, the control system needs very reliable capability of deviation rectifying in order to ensure that the tunnel trajectory meets the permissible criterion. To this goal, we present an approach that adopts Markov decision process (MDP) theory to plan the driving force with explicit representation of the uncertainty during excavation. The shield attitudes of possi- ble world and driving forces during excavation are scattered as a state set and an action set, respectively. In particular, an evaluation function is proposed with consideration of the stability of driving force and the deviation of shield attitude. Unlike the deterministic approach, the driving forces based on MDP model lead to an uncertain effect and the attitude is known only with an imprecise probability. We consider the case that the transition probability varies in a given domain estimated by field data, and discuss the optimal policy based on the interval arithmetic. The validity of the approach is discussed by comparing the driving force planning with the actual operating data from the field records of Line 9 in Tianjin. It is proved that the MDP model is reasonable enough to predict the driving force for automatic deviation rectifying.HU XiangTao HUANG YongAn YIN ZhouPing XIONG YouLun 2012Science China(Technological Sciences)2012,55,4:6
8Flexible smart sensing skin for“Fly-by-Feel”morphing aircraft显示文摘Flexible smart sensing skin is a key enabling technology for the future'Fly-by-Feel'control of morphing aircraft.It represents the next-generation skin of aircraft that can exhibit a more powerful sensing function than a conventional one and could be mounted on arbitrary curvilinear surfaces,especially for advanced autonomic,morphing aircraft.Recent significant technical advances in flexible electronics have overcome many historic drawbacks of conventional smart skin,e.g.,only a limited number of discrete block sensors can be integrated due to the inevitable structural damage and heavy guidelines.Herein,we review the key developments in flexible sensors technology and highlight both the state-of-the-art devices and the potential applications for the measurement of aircraft.We begin with the importance of flexible smart skin for morphing aircraft and then expand to the latest progress in various types of flexible sensors.Then we highlight flexible sensors as smart skin to measure aerodynamic parameters and monitor the structural health,and further to achieve the Fly-by-Feel control.Finally,the challenges and opportunities on flexible smart sensing skin are discussed,from the functional design to practical applications.HUANG YongAn ZHU Chen XIONG WenNan WANG Yu JIANG YongGang QIU Lei GUO DongLiang HOU Chao JIANG Shan YANG ZhaoXi WANG Bo WANG Lu YIN ZhouPing 2022Science China(Technological Sciences)2022,65,1:6
9Dynamic full-color digital holographic 3D display on single DMD显示文摘Digital holography has high potentials for future 3D imaging and display technology.We present a method for a dynamic full-color digital holographic 3D display on single digital micro-mirror device(DMD)with full-color,high-speed and high-fidelity characteristics.We combine the square regions of adjacent micro-mirrors into super-pixels that can modulate amplitude and phase independently.Gray images are achieved by amplitude modulation and precise positioning of each color is achieved by phase modulation.The proposed method realizes a full-color imaging based on the three primary colors and achieves measured structural similarity of more than 88%and color similarity of more than 98%,while retaining the high switch speed of 9 kHz,thus achieving dynamic full-color 3D display on charge-coupled device(CCD).Chonglei Zhang Dongfang Zhang Zhouping Bian 2021Opto-Electronic Advances2021,4,3:6
10Dynamics of forest biomass carbon stocks from 1949 to 2008 in Henan Province,east-central China显示文摘We estimated forest biomass carbon storage and carbon density from 1949 to 2008 based on nine consecutive forest inventories in Henan Province,China.According to the definitions of the forest inventory,Henan forests were categorized into five groups: forest stands,economic forests,bamboo forests,open forests,and shrub forests.We estimated biomass carbon in forest stands for each inventory period by using the continuous biomass expansion factor method.We used the mean biomass density method to estimate carbon stocks in economic,bamboo,open and shrub forests.Over the 60-year period,total forest vegetation carbon storage increased from34.6 Tg(1 Tg = 1×10^(12)g) in 1949 to 80.4 Tg in 2008,a net vegetation carbon increase of 45.8 Tg.By stand type,increases were 39.8 Tg in forest stands,5.5 Tg in economic forests,0.6 Tg in bamboo forests,and-0.1 Tg in open forests combine shrub forests.Carbon storageincreased at an average annual rate of 0.8 Tg carbon over the study period.Carbon was mainly stored in young and middle-aged forests,which together accounted for 70–88%of the total forest carbon storage in different inventory periods.Broad-leaved forest was the main contributor to forest carbon sequestration.From 1998 to 2008,during implementation of national afforestation and reforestation programs,the carbon storage of planted forest increased sharply from 3.9 to 37.9 Tg.Our results show that with the growth of young planted forest,Henan Province forests realized large gains in carbon sequestration over a 60-year period that was characterized in part by a nation-wide tree planting program.Yanfang Wang Ling Liu Zhouping Shangguan 2018Journal of Forestry Research2018,29,2:5
11Remarks on Vanishing Viscosity Limits for the 3D Navier-Stokes Equations with a Slip Boundary Condition显示文摘The authors study vanishing viscosity limits of solutions to the 3-dimensional incompressible Navier-Stokes system in general smooth domains with curved boundaries for a class of slip boundary conditions.In contrast to the case of flat boundaries,where the uniform convergence in super-norm can be obtained,the asymptotic behavior of viscous solutions for small viscosity depends on the curvature of the boundary in general.It is shown,in particular,that the viscous solution converges to that of the ideal Euler equations in C([0,T];H1(Ω)) provided that the initial vorticity vanishes on the boundary of the domain.Yuelong XIAO1 Zhouping XIN2 1Institute for Computational and Applied Mathematics,Xiangtan University,Xiangtan 411105,Hunan,China The Institute of Mathematical Sciences,The Chinese University of Hong Kong,Hong Kong,China.2The Institute of Mathematical Sciences,The Chinese University of Hong Kong,Hong Kong,China. 2011Chinese Annals of Mathematics,Series B2011,32,3:4
12A Design of Observers for a Discrete Chaotic System显示文摘It is very easy to design an observer for a discrete chaotic system which possesses one non linear scalar quantity, and one can realize the synchronization between the investigated chaotic system and its observer easily. This method is applied to two chaotic systems.CHENXi-ming ZHOUPing 2001The Journal of China Universities of Posts and Telecommunications2001,8,4:4
13Theoretical and experimental study of 2D conformability of stretchable electronics laminated onto skin显示文摘Smoothly attaching the stretchable epidermal electronic devices(EEDs) onto the skin surface is highly desired to improve the measurement accuracy of electrophysiological signal.The paper presents an analytical approach to study interfacial mechanics of the 2D planar EEDs on the checkerboard buckling patterns of human skin.Energy variation method is proposed to determine a criterion whether EEDs laminate conformally onto the skin surface under undeformed and stretched cases.EEDs with low bending stiffness(thin,soft devices/backing layer),smooth and soft skin,and strong adhesion promote conformal contact.Furthermore,the adhesion energy at the EED/skin interface is measured by the homemade peeling experiment platform with different substrate thicknesses and areal coverages.The upper limit of the areal coverage for EED conformal contact with the skin is proposed with given EED/skin properties.Conformability of EEDs are validated by experiments with different substrate thickness,areal coverage and external loadings.It provides a design guideline for EED to conformally contact with the skin surface for more accurate biological signal monitoring.DONG WenTao XIAO Lin ZHU Chen YE Dong WANG ShuoDao HUANG YongAn YIN ZhouPing 2017Science China(Technological Sciences)2017,60,9:4
14Hematoma enlargement-related factors in hypertensive cerebral hemorrhage显示文摘BACKGROUND:Continuous hemorrhage or hematoma enlargement often occurs following cerebral hemorrhage attacks. OBJECTIVE: To retrospectively analyze the influential factors for hematoma enlargement in patients with hypertensive cerebral hemorrhage prior to minimally invasive surgery. DESIGN, TIME AND SETTING: A comparative analysis of 90 patients with cerebral hemorrhage undergoing minimally invasive surgery at the Department of Neurology, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology between April 2005 and February 2007. PARTICIPANTS: Fifty-eight males and thirty-one females aged (52.7 ± 5.23) years (range, 28-73 years). METHODS: Cranial CT was performed twice to objectively identify hematoma enlargement. Patients with hematoma enlargement prior to surgery were selected as the observation group (n = 30), and those with no obvious hematoma changes served as the control group (n = 60). Following cranial CT localization, the two groups underwent minimally invasive hematoma aspiration and drainage, according to Standardized Treatment Guidelines for Micro-invasive Aspiration and Drainage of Intracranial Hematoma. MAIN OUTCOME MEASURES: Hemorrhage site, coagulation function, diabetes history, and clinical symptoms. RESULTS: There were no significant differences in hemorrhage sites between the two groups (χ2 = 2.262, P > 0.05). The percent of intemperance patients in the observation group was significantly larger than the control group (χ2 = 6.923, P < 0.01). No significant differences in terms of percent of coagulation dysfunction or diabetes were determined between the two groups (χ2 = 0.03, 0.08, P > 0.05). The percent of patients with clinical deterioration was significantly higher in the observation group, compared to the control group (χ2 = 25.57, P < 0.01). CONCLUSION: Intemperance and preoperative clinical deterioration may increase incidence of hematoma enlargement prior to minimally invasive surgery in patients with hypertensive cerebral hemorrhage.Dengji Pan Zhouping Tang Feng Xu Di Chen Xingyong Chen Xiangwu Meng Suiqiang Zhu Wei Wang 2008Neural Regeneration Research2008,3,8:4
15Highly efficient visible photocatalytic disinfection and degradation performances of microtubular nanoporous g-C3N4 via hierarchical construction and defects engineering显示文摘Herein,microtubular nanoporous g-C3N4(TPCN)with hierarchical structure and nitrogen defects was prepared via a facile self-templating approach.On one hand,the hexagonal tubular structure can facilitate the light reflection/scattering,provide internal/external active sites,and endow the electron with oriented transfer channels.The well-developed nanoporosity can result in large specific surface area and abundant accessible channels for charge migration.On the other hand,the existence of nitrogen vacancies can improve the light harvesting(>450 nm)and prompt charge separation by acting as the shallow charge traps.More NHxgroups in g-C3N4 framework can promote the interlayer charge transport by generating hydrogen-bonding interaction between C3N4 layers.Therefore,TPCN possessed highly efficient visible photocatalytic performances to effectively inactivate Escherichia coli(E.coli)cells and thoroughly mineralize organic pollutants.TPCN with the optimum bactericidal efficiency can completely inactivated5×10^6 cfu mL^-1 of E.coli cells after 4 h of irradiation treatment,while about 74.4%of E.coli cells were killed by bulk g-C3N4(BCN).Meanwhile,the photodegradation rate of TPCN towards methylene blue,amaranth,and bisphenol A were almost 3.1,2.5 and 1.6 times as fast as those of BCN.Furthermore,h^+and·O2^- were the reactive species in the photocatalytic process of TPCN system.Jing Xu Zhouping Wang Yongfa Zhu 2020Journal of Materials Science & Technology2020,47,14:3
16Geology,Geochemistry and Minerogenesis of the Shijuligou Zinc-Copper Deposit in Gansu,China显示文摘The Shijuligou deposit was separated by an arcuate ductile shear zone cross the center of the deposit region, resulting in the difference between the southern and northern ore bodies. The lead (Pb) isotopic data of ores of the Shijuligou copper deposit have averages of 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb in 17.634, 15.444, and 37.312, respectively. It has been shown that ore-forming metals originated from intrusive and extrusive rocks in the upper part of ophiolites. The sulfur isotopic data of pyrite and chalcopyrite in the northern part change from +7.61‰ to +8.09‰ and +4.95‰ to +8.88‰ in the southern part. Isotopes of δ18O in the Shijuligou copper deposit are between +11.1‰ and +18.6‰, with the calculated δ18OH2O at +0.65‰. It is suggested that the mineralized fluid is a mixture of magma fluid, meteorological water, and seawater through circulating and leaching metals from the volcanic rocks. The zircon uranium-lead (U-Pb) dating of gabbro is 457.9±1.2 Ma, and the lower crossing age of the discordant and concordia curves of pyroxene spilite of zircon is 454±15 Ma. It is indicated that the Shijuligou deposit formed in a new ocean crust (ophiolite) of the back-arc basin in the late Ordovician. Mineralization should occur in the intermittence period after strong volcanic activity, and the age should be the late Ordovician. Moreover, the mineralization of ophiolite-hosted massive sulfide deposits in the ancient orogenic belt of the late Ordovician in the northern Qilian Mountains was controlled by the primary fault/fracture, with the forming of a metallogenic hydrothermal system by a mixture of volcanic magma fluid and seawater, which circularly leached the metallogenic metals from the volcanic rocks, resulting in their accumulation. The ore bodies were transformed with morphology and metallogenic elements. Jasperoid is an important sign for prospecting such deposits. There were many island arcs in the continent of China. This study provides evidence for understanding and exploration of ophiolite-hosted massive sulfide deposits in western China, especially in the area of northern Qilian Mountains.LI Wenyuan DENG Jun GAO Yongbao GUO Zhouping ZHANG Zhaowei SONG Zhongbao 2009Acta Geologica Sinica(English Edition)2009,83,6:3
17Simulating the vegetation-producing process in small watersheds in the Loess Plateau of China显示文摘Small watersheds are the basic composition unit of the Loess Plateau in China. An accurate estimation of vegetation net primary productivity (NPP) is of great significance for eco-benefit evaluation in small watershed management in this region. Here we describe the development and testing of a vegetation-producing process model (VPP) of a small watershed in the Loess Plateau. The model couples three modules: radiation adjustment; soil hydrological processes; and vegetation carbon assimilation. Model validation indicates that the VPP model can be used to estimate the NPP of small watersheds in the region. With the VPP model, we estimated the spatial NPP distributions in the Yangou watershed for 2007. The results show that in the Yangou watershed the NPP is relatively low, averaging 168 g C/(m 2 ·a). Trees and shrubs have a higher NPP than crops and grasses. The NPP is larger on the partly shaded and shaded slopes than on the partly sunny and sunny slopes. The NPP on the slopes increases gradually on 0-20° slopes and decreases slightly on slopes steeper than 20°. Our simulation indicates that the vegetation type is the most important factor in determining the NPP distribution in small watersheds in the Loess Plateau.KaiBo WANG ZhouPing SHANGGUAN 2012Journal of Arid Land2012,4,3:3
18Carbon inputs regulate the temperature sensitivity of soil respiration in temperate forests显示文摘Litter and root activities may alter the temperature sensitivity(Q_(10))of soil respiration.However,existing studies have not provided a comprehensive understanding of the effects of litter and root carbon inputs on the Q_(10)of soil respiration in different seasons.In this study,we used the trench method under in situ conditions to measure the total soil respiration(R_(total)),litter-removed soil respiration(R_(no-litter)),root-removed soil respiration(R_(no-root)),and the decomposition of soil organic matter(i.e.,both litter and root removal;R_(SOM))in different seasons of pioneer(Populus davidiana Dode)and climax(Quercus liaotungensis Mary)forests on the Loess Plateau,China.Soil temperature,soil moisture,litter biomass,fine root biomass,litter carbon,and root carbon were analyzed to obtain the drive mechanism of the Q_(10)of soil respiration in the two forests.The results showed that the Q_(10)of soil respiration exhibited seasonality,and the Q_(10)of soil respiration was higher in summer.The litter enhanced the Q_(10)of soil respiration considerably more than the root did.Soil temperature,soil moisture,fine root biomass,and litter carbon were the main factors used to predict the Q_(10)of different soil respiration components.These findings indicated that factors affecting the Q_(10)of soil respiration highly depended on soil temperature and soil moisture as well as related litter and root traits in the two forests,which can improve our understanding of soil carbon–climate feedback in global warming.The results of this study can provide reference for exploring soil respiration under temperate forest restoration.LIU Yulin LI Jiwei HAI Xuying WU Jianzhao DONG Lingbo PAN Yingjie SHANGGUAN Zhouping WANG Kaibo DENG Lei 2022Journal of Arid Land2022,14,9:3
19On the Inviscid Limit of the 3D Navier–Stokes Equations with Generalized Navier-Slip Boundary Conditions显示文摘In this paper,we investigate the vanishing viscosity limit problem for the 3-dimensional(3D)incompressible Navier-Stokes equations in a general bounded smooth domain of R^3 with the generalized Navier-slip boundary conditions u^ε·n=0,n×(ω^ε)=[Bu^ε]τon∂Ω.Some uniform estimates on rates of convergence in C([0,T],L2(Ω))and C([0,T],H^1(Ω))of the solutions to the corresponding solutions of the ideal Euler equations with the standard slip boundary condition are obtained.Yuelong Xiao Zhouping Xin 2013Communications in Mathematics and Statistics2013,1,3:3
20Existence of Solutions for Three Dimensional Stationary Incompressible Euler Equations with Nonvanishing Vorticity显示文摘In this paper,solutions with nonvanishing vorticity are established for the three dimensional stationary incompressible Euler equations on simply connected bounded three dimensional domains with smooth boundary.A class of additional boundary conditions for the vorticities are identified so that the solution is unique and stable.Chunlei TANG Zhouping XIN Department of Mathematics,Southwest University,Chongqing 400715,China The Institute of Mathematical Sciences,The Chinese University of Hong Kong,Hong Kong,China The Institute of Mathematical Sciences,The Chinese University of Hong Kong,Hong Kong,China 2009Chinese Annals of Mathematics,Series B2009,30,6:3
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