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| 1 | Control-oriented Modeling for Air-breathing Hypersonic Vehicle Using Parameterized Configuration Approach显示文摘This article presents a parameterized configuration modeling approach to develop a 6 degrees of freedom (DOF) rigid-body model for air-breathing hypersonic vehicle (AHV). The modeling process involves the parameterized configuration design, inviscous hypersonic aerodynamic force calculation and scramjet engine modeling. The parameters are designed for airframe-propulsion integration configuration, the aerodynamic force calculation is based on engineering experimental methods, and the engine model is acquired from gas dynamics and quasi-one dimensional combustor calculations. Multivariate fitting is used to obtain analytical equations for aerodynamic force and thrust. Furthermore, the fitting accuracy is evaluated by relative error (RE). Trim results show that the model can be applied to the investigation of control method for AHV during the cruise phase. The modeling process integrates several disciplines such as configuration design, aerodynamic calculation, scramjet modeling and control method. Therefore the modeling method makes it possible to conduct AHV aerodynamics/propulsion/control integration design. | LI Huifeng LIN Ping XU Dajun | 2011 | Chinese Journal of Aeronautics2011，24，1： | 29 |
| 2 | INITIAL VALUE PROBLEMS FOR SECOND ORDER IMPULSIVE INTEGRO-DIFFERENTIAL EQUATIONS IN BANACH SPACES显示文摘INITIALVALUEPROBLEMSFORSECONDORDERIMPULSIVEINTEGRO┐DIFFERENTIALEQUATIONSINBANACHSPACES**GUODAJUN*AbstractManuscriptreceivedJu... | GUO DAJUN *Department of Mathematics,Shandong Universty,Jinan 250100,Shandong,China. **Project supported by the National Natural Science Foundation of China and the Doctoral Program Foundation of the State Education Commission of China. | 1997 | Chinese Annals of Mathematics,Series B1997，18，4： | 28 |
| 3 | INTEGRO-DIFFERENTIAL EQUATIONS ONUNBOUNDED DOMAINS IN BANACH SPACES显示文摘This paper investigates the maximal and minimal solutions of initial value problem for n-th order nonlinear integro-differential equations of Volterra type on an infinite interval in a Banach space by establishing a comparison result and using the monotone iterative technique. | GUO DAJUN(Department of Mathematics, Shandong University Jinan 250100, China) | 1999 | Chinese Annals of Mathematics,Series B1999，20，4： | 19 |
| 4 | An epidemiological analysis of the Beijing 2008 Hand-Foot-Mouth epidemic显示文摘This paper presents an empirical analysis of the epidemiological data concerning the 18445 HFMD-infected cases in Beijing in 2008.The main findings are as follows.(i) Seasonal variations in incidence were observed,with a peak observed during the summer season,especially in May.Male patients outnumber female patients by 1.57:1.(ii) Most cases occurred in children 4 years old or younger.Outperforming Weibull distribution and Gamma distribution as to model fitness when analyzing patient ages,log-normal distribution indicates that the estimated mean age is 3.4 years.(iii) The age distribution seems to indicate cyclic peaks with roughly one-year intervals.(iv) Correlation analyses (ρ=0.9864) show that time of birth in different months has an impact on the chance of being infected by HFMD.Birth month seems to present a high risk factor on infants and young children.(v) The morbidity rate is 132.7/100000 during the HFMD epidemic in Beijing in 2008.The morbidity map shows that the risks of HFMD infection in areas close to the city center and suburbans are much lower than those in the urban-rural transition zones.Spatial risks inferred from the morbidity map demonstrate a clear circular pattern.(vi) The prevention and control measures taken by the public health departments seem to be effective during the summer season,resulting in the early ending of the epidemic (one month earlier than the natural season) and reduced outbreak size. | CAO ZhiDong ZENG DaJun WANG QuanYi ZHENG XiaoLong WANG FeiYue | 2010 | Chinese Science Bulletin2010，55，12： | 12 |
| 5 | A high precision calibration method for long baseline acoustic positioning systems显示文摘To solve the problem that traditional long baseline(LBL) positioning system is easily affected by severe sound speed varying results in low calibration precision, low efficiency and inconsistent position using different references, we propose a high precision array calibration method. We use distances between beacons to build error adjustment model. This model improves the calibration performance of traditional calibration method. The theory shows this method can achieve equal calibration precision with distance measurement precision in horizon. This method can improve the calibration efficiency, solve position ambiguity and achieve high precision especially in deep ocean. The shallow water experiment shows this method has millimeter calibration precision which is equal to distance measurement error. The calibration precision improves from centimeter to millimeter compared to traditional calibration method.The method also decreases the operation complexity. The localized positions are more close to GPS compared to traditional method, which has great application values. | HAN Yunfeng ZHENG Cuie SUN Dajun | 2017 | Chinese Journal of Acoustics2017，36，4： | 11 |
| 6 | Seafloor geodetic network establishment and key technologies显示文摘Seafloor geodetic network construction involves the development of geodetic station shelter, network configuration design, location selection and layout, surveying strategy, observation model establishment and optimization, data processing strategy and so on. This paper tries to present main technological problems involved in the seafloor geodetic network construction, and seek the technically feasible solutions. Basic conceptions of developing seafloor geodetic station shelters for shallow sea and deep-sea are described respectively. The overall criteria of seafloor geodetic network construction for submarine navigation and those of network design for crustal motion monitoring are both proposed. In order to enhance application performances of the seafloor geodetic network, the seafloor network configuration should prefer a symmetrical network structure. The sea surface tracking line measurements for determining the seafloor geodetic station position should also adopt an approximately symmetrical configuration, and we recommend circle tracking line observations combined with cross-shaped line(or double cross-shape line) observations for the seafloor positioning mode. As to the offset correction between the Global Navigation Satellite System antenna phase center and the acoustic transducer, it is recommended to combine the calibration through external measurements and model parameter estimation. Besides, it is suggested to correct the sound speed error with a combination of observation value correction and parameterized model correction, and to mainly use the model correction to reduce the influence of acoustic ray error on the seafloor positioning. Following the proposed basic designs, experiments are performed in shallow sea area and deep-sea area respectively. Based on the developed seafloor geodetic shelter and sufficient verification in the shallow sea experiment, a long-term seafloor geodetic station in the deep-sea area of 3000 m depth was established for the first time, and the preliminary positioning result shows that the internal precision of this station is better than 5 cm. | Yuanxi YANG Yanxiong LIU Dajun SUN Tianhe XU Shuqiang XUE Yunfeng HAN Anmin ZENG | 2020 | Science China Earth Sciences2020，63，8： | 11 |
| 7 | New double Wronskian solutions of the AKNS equation显示文摘Soliton solutions, rational solutions, Matveev solutions, complexitons and interaction solutions of the AKNS equation are derived through a matrix method for constructing double Wronskian entries. The latter three solutions are novel. Moreover, rational solutions of the nonlinear Schrodinger equation are obtained by reduction. | CHEN DenYuan ZHANG DaJun BI JinBo | 2008 | Science China Mathematics2008，51，1： | 8 |
| 8 | Alternative splicing and expression of the insulin-like growth factor (IGF-1) gene in osteoblasts under mechanical stretch显示文摘(IGF-1 ) 像胰岛素的生长因素 1 支持造骨细胞区别和骨头形成,和它的表示被机械段导致,因此, IGF-1 被认为连接机械刺激和本地织物回答的一个受动器分子。在这研究,一台机械拉长设备被设计把生理的水平静电干扰或周期的拉长刺激用于造骨细胞。IGF-1 mRNA 的不同 isoforms 被 RT-PCR 用各自的教材从房间放大,这些放大产品被定序。产品被发现被造骨细胞有选择地在拉长刺激下面生产的拼接的 IGF-1 的 iso 形式。ThisIGF-1 isoform 与原来在肌肉细胞被识别的 mechano 生长因素(MGF ) 有相同顺序。肝类型 IGF (L.IGF-1 ) 和在在段刺激下面的造骨细胞的 MGF 的表示的规定进一步用半量的 RT-PCR 被学习。Stretchstimulation 被发现 IGF-1 (L.IGF-1 和 MGF ) 的表示到职业人员警句,并且为两 isoformsexpression,更多被周期的段有效地比静态的段刺激。MGF 仅仅在受到机械段的造骨细胞被检测,建议 MGF 是段敏感生长因素。MGF 的表示比 L.IGF-1 的早达到顶点,它类似于他们在肌肉的规定并且作为在肌肉房间在骨头建议了 MGF 和 L.IGF-1 的类似的角色。在造骨细胞的 MGF 和 L.IGF-1 的功能将被进一步试验性的研究建立。 | XIAN Chengyu WANG Yuanliang ZHANG Bingbing TANG Liling PAN Jun LUO Yanfeng JIANG Peng LI Dajun | 2006 | Chinese Science Bulletin2006，51，22： | 7 |
| 9 | Oroclinal bending and block rotations in South China since the Mesozoic——Geological and paleomagnetic evidence显示文摘THE South China Block exhibits a complex structural pattern in its Neoproterozoic-Mesozoic sedimentary cover. The lack of knowledge about the formation of this pattern hinders our understanding of the regional tectonic evolution and paleogeography, and the reconstruction of Phanerozoic apparent polar wander path(s). In this note we present a synthesis based on a paleomagnetic and tectonic analysis, which suggests that (i) the structural pattern over | LI Zhengxiang, FANG Dajun, Christopher McA. Powell and LOU Gang1. Department of Geology and Geophysics, The University of Western Australia, Nedlands WA 6907, Australia 2. Department of Earth Sciences, Zhejiang University, Hangzhou 310027, China | 1997 | Chinese Science Bulletin1997，42，2： | 7 |
| 10 | Real-time compensation of phase drift for phase-encoded quantum key distribution systems显示文摘Phase drift is an inherent problem in phase-encoded quantum key distribution(QKD) systems.The current active phase trackingand compensation solutions cannot satisfy the requirements of a system with nonlinearity in phase modulation.This paper presents a four-phase scanning method,which is based on the quantitative analysis of the quantum bit error rate(QBER) from phasedrift and the performance requirements of phase compensation.By obtaining the four interference fringes and adjusting the codingmatrix of the system,this method automatically calculates the accurate driving voltages for the phase modulator.The implementation and experimental tests show that the proposed method can compensate phase drift caused by environmental changes and thesystem's nonlinearity,and is applicable to large-scale QKD networks. | ZHANG LiJun WANG YongGang YIN ZhenQiang CHEN Wei YANG Yang ZHANG Tao HUANG DaJun WANG Shuang LI FangYi HAN ZhengFu | 2011 | Chinese Science Bulletin2011，56，22： | 6 |
| 11 | Decentralized Event-Triggered Average Consensus for Multi-Agent Systems in CPSs with Communication Constraints显示文摘The paper investigates decentralized event-triggered average consensus problem for multi-agent systems in cyberphysical systems(CPSs) with communication constraints.To reduce communication burden and improve the communication efficiency of multi-agent systems in CPSs,event-trigger is distributed at subsystem/agent level.A multi-agent system is then modeled as a reduced dimension hybrid system by taking into account decentralized event-triggered mechanism,communication delays and data dropouts within one framework.Some sufflcient conditions for average consensus of each agent and an upper bound of communication delay and maximal allowable number of successive data dropouts(MANSD) are obtained,which can conveniently provide the relationship between the triggering parameters,communication constraints and the system stability.Specially,the quantitative relationship between the triggering parameters,MANSD and the system stability is derived.Finally,simulation results are given to illustrate the effectiveness of the proposed method. | Zhaoxia Wang Minrui Fei Dajun Du Min Zheng | 2015 | IEEE/CAA Journal of Automatica Sinica2015，2，3： | 6 |
| 12 | IL-17 sustains the plasma cell response via p38-mediated Bcl-xL RNA stability in lupus pathogenesis显示文摘Recent studies have demonstrated a central role for plasma cells in the development of autoimmune diseases,such as systemic lupus erythematosus(SLE).Currently,both the phenotypic features and functional regulation of autoreactive plasma cells during SLE pathogenesis remain largely unclear.In this study,we first found that a major subset of IL-17 receptor-expressing plasma cells potently produced anti-dsDNA IgG upon IL-17A(IL-17)stimulation in SLE patients and lupus mice.Using a humanized lupus mouse model,we showed that the transfer of Th17 cell-depleted PBMCs from lupus patients resulted in a significantly reduced plasma cell response and attenuated renal damage in recipient mice compared to the transfer of total SLE PBMCs.Moreover,long-term BrdU incorporation in lupus mice detected highly enriched long-lived BrdU+subsets among IL-17 receptor-expressing plasma cells.Lupus mice deficient in IL-17 or IL-17 receptor C(IL-17RC)exhibited a diminished plasma cell response and reduced autoantibody production with attenuated renal damage,while the adoptive transfer of Th17 cells triggered the plasma cell response and renal damage in IL-17-deficient lupus mice.In reconstituted chimeric mice,IL-17RC deficiency resulted in severely impaired plasma cell generation but showed no obvious effect on germinal center B cells.Further mechanistic studies revealed that IL-17 significantly promoted plasma cell survival via p38-mediated Bcl-xL transcript stabilization.Together,our findings identified a novel function of IL-17 in enhancing plasma cell survival for autoantibody production in lupus pathogenesis,which may provide new therapeutic strategies for the treatment of SLE. | Kongyang Ma Wenhan Du Fan Xiao Man Han Enyu Huang Na Peng Yuan Tang Chong Deng Lixiong Liu Yulan Chen Jingjing Li Shiwen Yuan Qin Huang Xiaoping Hong Dajun Hu Xiaoyan Cai Quan Jiang Dongzhou Liu Liwei Lu | 2021 | Cellular & Molecular Immunology2021，18，7： | 6 |
| 13 | Parthenolide increases the sensitivity of gastric cancer cells to chemotherapy显示文摘OBJECTIVE:To investigate the effect of parthenolide(PTL),a sesquiterpene lactone medicinal compound,on the sensitivity of the gastric cancer cell line SGC7901 and the DPP-and ADR-resistant sublines SGC7901/DDP and SGC7901/ADR to cisplatin[diamminedichloroplatinum(Ⅱ),DDP]and adriamycin(ADR)in vitro.METHODS:SGC7901,SGC7901/DDP,and SGC7901/ADR were treated with various concentrations of PTL alone or in combination with DDP or ADR.The effects on cell proliferation,apoptosis,and expression/activity of several proliferation/apoptosis-related proteins[B-cell lymphoma-2(Bcl-2),cyclin D1,nuclear factor-kappa B(NF-κB),and Caspase-8]and drug transporters(P-glycoprotein and multidrug resistance protein-1)were measured using flow cytometry,Western blotting,and in vitro activity assays.RESULTS:Treatment of SGC7901 cells with PTL inhibited cell growth,increased apoptosis,and sensitized the cells to DPP.Mechanistically,PTL treatment resulted in downregulation of NF-κB activity and Bcl-2 expression,and upregulation of Caspase-8 activity.Similarly,PTL co-treatment of SGC7901/DDP and SGC7901/ADR overcame their resistance to DDP and ADR,respectively,with concomitant inhibition of NF-κB,Bcl-2,Cyclin D1,P-glycoprotein,and multidrug resistance protein-1 expression and/or activity.CONCLUSION:PTL treatment decreases drug resistance in SGC7901,SGC7901/DDP,and SGC7901/ADR cells,as reflected by induction of apoptosis,inhibition of proliferation,downregulation of pro-survival and drug resistance pathways,and upregulation of pro-apoptotic pathways.Our results suggest that co-treatment with PTL may thus complement existing therapies for gastric cancer. | Liu Minghua Yang Ying Liu Dajun Cao Ye Li Yan | 2020 | Journal of Traditional Chinese Medicine2020，40，6： | 5 |
| 14 | Spatio-temporal evolution of Beijing 2003 SARS epidemic显示文摘Studying spatio-temporal evolution of epidemics can uncover important aspects of interaction among people, infectious diseases, and the environment, providing useful insights and modeling support to facilitate public health response and possibly prevention measures. This paper presents an empirical spatio-temporal analysis of epidemiological data concerning 2321 SARS-infected patients in Beijing in 2003. We mapped the SARS morbidity data with the spatial data resolution at the level of street and township. Two smoothing methods, Bayesian adjustment and spatial smoothing, were applied to identify the spatial risks and spatial transmission trends. Furthermore, we explored various spatial patterns and spatio-temporal evolution of Beijing 2003 SARS epidemic using spatial statistics such as Moran’s I and LISA. Part of this study is targeted at evaluating the effectiveness of public health control measures implemented during the SARS epidemic. The main findings are as follows. (1) The diffusion speed of SARS in the northwest-southeast direction is weaker than that in northeast-southwest direction. (2) SARS’s spread risk is positively spatially associated and the strength of this spatial association has experienced changes from weak to strong and then back to weak during the lifetime of the Beijing SARS epidemic. (3) Two spatial clusters of disease cases are identified: one in the city center and the other in the eastern suburban area. These two clusters followed different evolutionary paths but interacted with each other as well. (4) Although the government missed the opportunity to contain the early outbreak of SARS in March 2003, the response strategies implemented after the mid of April were effective. These response measures not only controlled the growth of the disease cases, but also mitigated the spatial diffusion. | CAO ZhiDong ZENG DaJun ZHENG XiaoLong WANG QuanYi WANG FeiYue WANG JinFeng WANG XiaoLi | 2010 | Science China Earth Sciences2010，53，7： | 5 |
| 15 | Synthetic aperture sonar movement compensation algorithm based on time-delay and phase estimation显示文摘The effects of movement errors on imaging results of synthetic aperture sonar andt he necessity of movement compensation are discussed. Based on analyzing so-called displaced phase center algorithm, an improved algorithm is proposed. In this method, the time delay is estimated firstly, then the phase is estimated for the residual error, so that the range of movement error suited to the algorithm is extended to some extent. Some simulation results on computer and experimental results in the test tank using the proposed algorithm are given as well. | JIANG Nan SUN Dajun TIAN Tan(Harbin Engineering University Harbin 150001) | 2003 | Chinese Journal of Acoustics2003，22，3： | 4 |
| 16 | Improvement of Seafloor Positioning Through Correction of Sound Speed Profile Temporal Variation显示文摘Dear Editor,This letter proposes a high-precision seafloor transponder positioning method based on the correction of sound speed profile(SSP)temporal variation.In the proposed method,the ocean sound speed error is modeled as the temporal variation of a background SSP,and the linearized expression of the acoustic travel time with respect to the sound speed coefficient is derived based on the ray acoustic model.Moreover,the proposed method introduces the constraint of acoustic ranging observations between seafloor transponders and determines the weights of travel time and ranging observations using Akaike’s Bayesian information criterion(ABIC)to reduce the positioning error caused by the correlation between sound speed and position parameters.The experimental results in the South China Sea show that the proposed method performs better than the global navigation satellite system-acoustic ranging combined positioning solver(GARPOS)[1],in terms of rigid distance errors and long baseline positioning accuracy. | Miao Yu Kuijie Cai Cuie Zheng Dajun Sun | 2023 | IEEE/CAA Journal of Automatica Sinica2023，10，4： | 3 |
| 17 | MULTIPLE POSITIVE SOLUTIONS FOR FIRST ORDER IMPULSIVE SUPERLINEAR INTEGRO-DIFFERENTIAL EQUATIONS ON THE HALF LINE显示文摘In this paper, the author discusses the multiple positive solutions for an infinite boundary value problem of first order impulsive superlinear integro-differential equations on the half line by means of the fixed point theorem of cone expansion and compression with norm type. | Guo Dajun | 2011 | Acta Mathematica Scientia2011，31，3： | 3 |
| 18 | Generalized Cauchy Matrix Approach for Lattice Boussinesq-Type Equations显示文摘The authors generalize the Cauchy matrix approach to get exact solutions to the lattice Boussinesq-type equations:lattice Boussinesq equation,lattice modified Boussinesq equation and lattice Schwarzian Boussinesq equation.Some kinds of solutions including soliton solutions,Jordan block solutions and mixed solutions are obtained. | Songlin ZHAO Dajun ZHANG Ying SHI | 2012 | Chinese Annals of Mathematics,Series B2012，33，2： | 3 |
| 19 | Two-layer networked learning control using self-learning fuzzy control algorithms显示文摘Since the existing single-layer networked control systems have some inherent limitations and cannot effectively handle the problems associated with unreliable networks, a novel two-layer networked learning control system (NLCS) is proposed in this paper. Its lower layer has a number of local controllers that are operated independently, and its upper layer has a learning agent that communicates with the independent local controllers in the lower layer. To implement such a system, a packet-discard strategy is firstly developed to deal with network-induced delay and data packet loss. A cubic spline interpolator is then employed to compensate the lost data. Finally, the output of the learning agent based on a novel radial basis function neural network (RBFNN) is used to update the parameters of fuzzy controllers. A nonlinear heating, ventilation and air-conditioning (HVAC) system is used to demonstrate the feasibility and effectiveness of the proposed system. | Du Dajun Fei Minrui Hu Huosheng Li Lixiong | 2007 | 仪器仪表学报2007，28，12： | 3 |
| 20 | Numerical Simulation of 2D Supersonic Magnetohydrodynamic Channel and Study on Hall Effect显示文摘In this research effort,numerical simulation of two-dimensional magnetohydrodynamic(MHD) channel is performed and Hall effect is studied.The computational model consists of the Navier-Stokes(N-S) equations coupled with electrical-magnetic source terms,Maxwell equations and the generalized Ohm's law.Boundary conditions for the electrical potential equation considering Hall effect are derived.To start with,the MHD channel with single-pair electrodes is studied and flow of the electric current is in accordance with physical principle.Then the MHD channel with five-pair electrodes is numerically simulated.The results show that the electrical current concentrates on the downstream of the anode and the upstream of the cathode due to Hall effect,and the flow field becomes asymmetrical.At the current value of the magnetic interaction parameter,the electrical-magnetic force affects the flow remarkably,decreasing the outlet Mach number and increasing the outlet pressure;what's more,the flow structure in the channel becomes extremely complex.Performances of MHD channels with continual electrodes and segmented electrodes are compared.The results show that performance of the MHD channel with segmented electrodes is better than that with continual electrodes with the increase of Hall parameter. | ZHENG Xiaomei LU Haoyu XU Dajun CAI Guobiao | 2011 | Chinese Journal of Aeronautics2011，24，2： | 3 |
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