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Chinese Journal of Aeronautics 2024年第5期37卷 349-362页

作者： Zhengjie LI Yujie WEI Junwei XIE haowei zhang Yu TIAN Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China Air Force Xi’an Flying College Xi’an 710300China Air and Missile Defense Institute Air Force Research InstituteBeijing 100085China School of Economics and Management Beihang UniversityBeijing 100191China

This paper investigates the problem of Joint Radar Node Selection and Power Allocation(JRNSPA)in the Multiple Radar System(MRS)in the blanket jamming *** radar node independently tracks moving target and subsequently transmits the raw observation data to the fusion center,which formulates a centralized tracking network *** order to establish a practical blanket jamming environment,we suppose that each target carries the self-defense jammer which automatically implements blanket jamming to the radar nodes that exceed the preset interception ***,the Predicted Conditional Cramer-Rao Lower Bound(PC-CRLB)is derived and utilized as the tracking accuracy *** at ensuring both the tracking performance and the Low Probability of Intercept(LPI)performance,the resource-saving scheduling model is formulated to minimize the transmit power consumption while meeting the requirements of tracking ***,the Modified Zoutendijk Method Of Feasible Directions(MZMFD)-based two-stage solution technique is adopted to solve the formulated non-convex optimization *** results show the effectiveness of the proposed JRNSPA scheme.

关键词： Multiple Radar System(MRS) Centralized target tracking Resource scheduling Blanket jamming Low Probability of Intercept(LPI)

Against all odds:The road to success in the development of human immune reconstitution mice

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Animal Models and Experimental Medicine 2024年第4期7卷 460-470页

作者： Yixiao Bin Jing Ren haowei zhang Tianjiao zhang Peijuan Liu Zhiqian Xin Haijiao Yang Zhuan Feng Zhinan Chen Hai zhang School of Basic Medical Sciences Shaanxi University of Chinese MedicineXianyangChina Department of Cell Biology National Translational Science Center for Molecular MedicineFourth Military Medical UniversityXi'anChina State Key Laboratory of New Targets Discovery and Drug Development for Major Diseases Fourth Military Medical UniversityXi'anChina Department of Occupational&Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment School of Public HealthFourth Military Medical UniversityXi'anChina

The mouse genome has a high degree of homology with the human genome,and its physiological,biochemical,and developmental regulation mechanisms are similar to those of humans;therefore,mice are widely used as experimental ***,it is undeniable that interspecies differences between humans and mice can lead to experimental *** differences in the immune system have become an impor-tant factor limiting current immunological *** application of immunodefi-cient mice provides a possible solution to these *** transplanting human immune cells or tissues,such as peripheral blood mononuclear cells or hematopoietic stem cells,into immunodeficient mice,a human immune system can be reconstituted in the mouse body,and the engrafted immune cells can elicit human-specific immune *** have been actively exploring the development and differen-tiation conditions of host recipient animals and grafts in order to achieve better im-mune *** genetic engineering methods,immunodeficient mice can be further modified to provide a favorable developmental and differentiation microenvironment for the *** initially only being able to reconstruct single T lymphocyte lineages,it is now possible to reconstruct lymphoid and myeloid cells,providing important research tools for immunology-related *** this review,we compare the differences in immune systems of humans and mice,describe the devel-opment history of human immune reconstitution from the perspectives of immuno-deficient mice and grafts,and discuss the latest advances in enhancing the efficiency of human immune cell reconstitution,aiming to provide important references for im-munological related researches.

关键词： hematopoietic stem cell human immune reconstitution immune response immunodeficient mice peripheral blood mononuclear cell transplantation

MGMT activated by Wnt pathway promotes cisplatin tolerance through inducing slow-cycling cells and nonhomologous end joining in colorectal cancer

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Journal of Pharmaceutical Analysis 2024年第6期14卷 863-877页

作者： haowei zhang Qixin Li Xiaolong Guo Hong Wu Chenhao Hu Gaixia Liu Tianyu Yu Xiake Hu Quanpeng Qiu Gang Guo Junjun She Yinnan Chen Department of General Surgery The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an710061China Center for Gut Microbiome Research Med-X InstituteThe First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an710061China Department of High Talent The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an710061China

Chemotherapy resistance plays a pivotal role in the prognosis and therapeutic failure of patients with colorectal cancer(CRC).Cisplatin(DDP)-resistant cells exhibit an inherent ability to evade the toxic chemotherapeutic drug effects which are characterized by the activation of slow-cycle programs and DNA *** the elements that lead to DDP resistance,O^(6)-methylguanine(O^(6)-MG)-DNA-methyltransferase(MGMT),a DNA-repair enzyme,performs a quintessential *** this study,we clarify the significant involvement of MGMT in conferring DDP resistance in CRC,elucidating the underlying mechanism of the regulatory actions of MGMT.A notable upregulation of MGMT in DDP-resistant cancer cells was found in our study,and MGMT repression amplifies the sensitivity of these cells to DDP treatment in vitro and in ***,in cancer cells,MGMT overexpression abolishes their sensitivity to DDP ***,the interaction between MGMT and cyclin dependent kinase 1(CDK1)inducing slow-cycling cells is attainted via the promotion of ubiquitination degradation of ***,to achieve nonhomologous end joining,MGMT interacts with XRCC6 to resist chemotherapy *** transcriptome data from samples of 88 patients with CRC suggest that MGMT expression is co-related with the Wnt signaling pathway activation,and several Wnt inhibitors can repress drug-resistant *** summary,our results point out that MGMT is a potential therapeutic target and predictive marker of chemoresistance in CRC.

关键词： Colorectal cancer MGMT Chemotherapy resistance Slow-cycling cells Nonhomologous end joining Wnt pathway

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论羌塘含油气盆地关键地层划分对比问题

海相油气地质 2024年第1期29卷 17-29页

作者：王剑张豪薇张健沈利军张建勇付修根油气藏地质及开发工程国家重点实验室(西南石油大学) 西南石油大学羌塘盆地研究院西南石油大学地球科学与技术学院中国石油杭州地质研究院

羌塘含油气盆地勘探程度相对较低,一些关键地层的时代归属与划分对比尚存较大的争议,这制约了盆地石油地质条件评价与含油气系统分析。基于近年来在羌塘盆地获得的生物地层、年代地层、沉积层序、盆地演化等方面的最新资料,结合前人的... 详细信息

羌塘含油气盆地勘探程度相对较低,一些关键地层的时代归属与划分对比尚存较大的争议,这制约了盆地石油地质条件评价与含油气系统分析。基于近年来在羌塘盆地获得的生物地层、年代地层、沉积层序、盆地演化等方面的最新资料,结合前人的研究基础,重点对制约含油气盆地分析的关键地层时代归属问题开展了综合分析与客观评述。取得的主要认识包括:(1)新的同位素年代学资料证实,羌塘盆地存在前寒武系变质岩结晶基底,古生界基底埋深可达7~15 km,中生界沉积超覆在古生界褶皱系之上;(2)那底岗日组时代归属为晚三叠世,而不是早—中侏罗世;(3)南羌塘古油藏白云岩属于上三叠统,古油藏白云岩很可能“异地无根”,与布曲组为构造断裂接触;(4)南羌塘毕洛错油页岩时代归属为早侏罗世;(5)雀莫错组原定义为中侏罗统,研究证实其时代归属为早—中侏罗世;(6)胜利河—长蛇山油页岩Re-Os同位素定年及生物化石资料证明其为下白垩统海相地层;(7)同位素年代学及野外露头剖面资料证实,康托组与唢呐湖组为同期异相地层。羌塘盆地地层学研究新进展为完善盆地地层划分对比方案,乃至盆地含油气系统分析与盆地资源潜力评价提供了新的依据。

关键词：地层对比年代地层生物地层中—新生界羌塘盆地

基于十字中心定位算法的MEMS真空封装光学检漏方法

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传感器与微系统 2024年第10期43卷 146-149页

作者：张浩威侯虎旺赵旸张鹏中国科学院材料力学行为和设计重点实验室安徽合肥230026 中国科学技术大学精密科学仪器安徽普通高校重点实验室安徽合肥230026 中国科学技术大学精密机械与精密仪器系安徽合肥230026

典型的光学检漏方法需要对整幅干涉图甚至多幅干涉图进行图像处理,过程相对复杂。本文结合MEMS器件封装结构的对称特性以及变形分布特征,提出了一种简单、快捷的十字中心定位算法。通过确定干涉图案中心点坐标,获取中心线光强分布,进而... 详细信息

典型的光学检漏方法需要对整幅干涉图甚至多幅干涉图进行图像处理,过程相对复杂。本文结合MEMS器件封装结构的对称特性以及变形分布特征,提出了一种简单、快捷的十字中心定位算法。通过确定干涉图案中心点坐标,获取中心线光强分布,进而拟合得到样品中心线形貌。进一步利用封装结构中心点随真空度变化的相对位移,计算得到漏气率。本文以圆形封装结构为例,证明了该方法的可行性。

关键词：真空封装激光干涉光学检漏十字中心定位法

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一种防空服务质量模型下的集中式多输入多输出雷达三维机动跟踪功率分配方法

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兵工学报 2024年第4期45卷 1321-1331页

作者：李正杰陈红印谢军伟张浩为刘斌中国空气动力研究与发展中心高速空气动力研究所四川绵阳621000 空军研究院北京100085 空军工程大学防空反导学院陕西西安710051 国防大学联合作战学院北京100091

针对防空作战中现有多功能雷达功率资源利用率低的问题,提出一种基于服务质量(Quanlity of Service,QoS)模型的三维机动跟踪功率分配方法以差异化标准提升多目标跟踪性能。将目标三维机动模型建立为自适应当前统计模型,通过将加速度协... 详细信息

针对防空作战中现有多功能雷达功率资源利用率低的问题,提出一种基于服务质量(Quanlity of Service,QoS)模型的三维机动跟踪功率分配方法以差异化标准提升多目标跟踪性能。将目标三维机动模型建立为自适应当前统计模型,通过将加速度协方差与估计误差协方差矩阵相关联以实现自适应调整。在此基础上,对三维跟踪下的贝叶斯克拉美罗下界进行推导,并将其作为跟踪误差衡量指标。通过构建关于目标威胁度与期望跟踪精度的函数关系,建立防空QoS模型下的闭环功率优化分配机制。证明所构建功率优化分配模型是凸优化问题,并进一步转化为半正定规划问题进行求解。仿真结果表明,相对于传统功率分配方法,所提方法能显著提高全局跟踪效能。

关键词：集中式多输入多输出雷达功率分配三维机动跟踪防空作战凸优化

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Resource saving based dwell time allocation and detection threshold optimization in an asynchronous distributed phased array radar network

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Chinese Journal of Aeronautics 2023年第11期36卷 311-327页

作者： haowei zhang Weijian LIU Xiao YANG Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China Air Force Early Warning Academy Wuhan 410039China Chinese People’s Liberation Army 93557 Troops Shijiazhuang 050000China

The resource optimization plays an important role in an asynchronous Phased Array Radar Network(PARN)tracking multiple targets with Measurement Origin Uncertainty(MOU),i.e.,considering the false alarms and missed detections.A Joint Dwell Time Allocation and Detection Threshold Optimization(JDTADTO)strategy is proposed for resource saving in this *** Predicted Conditional Cramér-Rao Lower Bound(PC-CRLB)with Bayesian Detector and Amplitude Information(BD-AI)is derived and adopted as the tracking performance *** optimization model is formulated as minimizing the difference between the PC-CRLBs and the tracking precision thresholds under the constraints of upper and lower bounds of dwell time and false alarm *** is shown that the objective function is nonconvex due to the Information Reduction Factor(IRF)brought by the MOU.A cyclic minimizer-based solution is proposed for problem *** results confirm the flexibility and robustness of the JDTADTO strategy in both sufficient and insufficient resource *** results also reveal the effectiveness of the proposed strategy compared with the strategies adopting the BD without detection threshold optimization and amplitude information.

关键词： Asynchronous data fusion Bayesian detector Phased Array Radar Network(PARN) Predicted Conditional CramE´R-Rao Lower Bound(PC-CRLB) Resource management

Dot-shaped beamforming analysis based on OSB log-FDA

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Journal of Systems Engineering and Electronics 2020年第2期31卷 312-320页

作者： WANG Bo XIE Junwei zhang Jing zhang haowei Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China Highway Railway College Shaanxi Vocational and Technical College of TransportXi’an 710018China

The range and angle information of the frequency diverse array(FDA) cannot be exclusively determined at the output of the array because of the range-angle coupled transmit beampattern. The best decoupling approach is to form a dot-shaped beampattern rather than the S-shaped beampattern of the basic *** the degradation of the output signal-to-interferenceplus-noise ratio(SINR) caused by the coupled beampattern, we propose a dot-shaped beamforming method based on the analyzed overlapping subarray-based using a logarithmic offset and a subarray-based planar FDA using a logarithmically increasing frequency offset, with elements transmitting at multiple frequencies. Several simulation results demonstrate the effectiveness of the proposed method in transmit energy focusing, sidelobe suppression and array resolution.

关键词： subarray-based frequency diverse array(SB FDA) planar frequency diverse array(PFDA) decoupling dot-shaped beamforming

Beam resource scheduling for a VHF-MIMO radar network in low-angle tracking

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Chinese Journal of Aeronautics 2023年第4期36卷 423-441页

作者： haowei zhang Weijian LIU Taiyong FEI Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China Air Force Early Warning Academy Wuhan 410039China

The low-angle tracking in multipath interference is a challenging problem for the Very High Frequency(VHF)*** colocated Multi-Input Multi-Output(MIMO)technique can remedy such a *** this paper,a Joint Beam-Target Assignment and Power Allocation(JBTAPA)strategy is proposed for the VHF-MIMO radar network tracking low-angle *** core of the JBTAPA strategy is to improve the worst tracking accuracy among multiple targets by assigning appropriate beams to targets and allocating the power resource in each beam using the feedback information in the tracking *** into account the transmit multipath and receive multipath,we derive the Cramer-Rao Lower Bound(CRLB)on angle estimate,which is then incor-porated in the Predicted Conditional CRLB(PC-CRLB).A more accurate and consistent lower bound is provided as the optimization metric since the PC-CRLB is based on the most recently real-ized measurements.A two-stage-based technique is proposed to solve the JBTAPA problem,which is originally *** results verify the effectiveness and efficiency of the proposed *** results also imply that the target reflectivity plays one of the important roles in resource allocation.

关键词： Convex optimization Low-angle tracking MIMO radar PC-CRLB Resource allocation

Beamforming analysis based on CSB sin-FDA

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Journal of Systems Engineering and Electronics 2020年第1期31卷 73-84页

This paper studies the adaptive beamforming algorithm based on the frequency diverse array(FDA)array where the interference is located at the same angle(but different range)with the *** take the cross subarray-based FDA with sinusoidal frequency offset(CSB sin-FDA)as the receiving array instead of the basic *** sampling covariance matrix under insufficient snapshot can be corrected by the automatic diagonal loading *** the basis of decomposing the mismatched steering vector error into a vertical component and a parallel one,this paper searches the vertical component of the error by the quadratic constraint *** numerical simulation verifies that the beamformer based on the CSB sin-FDA can effectively hold the mainlobe at the target position when the snapshot is insufficient or the steering vector is mismatched.

关键词： receiving processing architectures minimum variance distortionless response(MVDR)beamformer cross subarraybased frequency diverse array with sinusoidal frequency offset(CSB sin-FDA) steering vector snapshots