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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第12期15卷 1087-1097页

作者： Yang GUO Xiang-hua WANG Jun hu Centre for Optical and Electromagnetic Research State Key Lab of MOI Zhejiang University

A new efficient parallel finite-difference time-domain(FDTD) meshing algorithm, based on the ray tracing technique, is proposed in this paper. This algorithm can be applied to construct various FDTD meshes, such as regular and conformal ones. The Microsoft F# language is used for the algorithm coding, where all variables are unchangeable with its parallelization advantage being fully exploited. An improved conformal FDTD algorithm, also integrated with an improved surface current algorithm, is presented to simulate some complex 3D models, such as a sphere ball made of eight different materials, a tank, a J-10 aircraft, and an aircraft carrier with 20 aircrafts. Both efficiency and capability of the developed parallel FDTD algorithm are validated. The algorithm is applied to characterize the induced surface current distribution on an aircraft or a warship.

关键词： Finite-difference time-domain(FDTD) Meshing Parallel Function language Surface current distribution

A Wideband High-Gain Sawtooth Slot Array Antenna with Frequency-Scanning at Lower Frequency and Fixed-Beam at Higher Frequency

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Chinese Journal of Electronics 2024年第2期33卷 463-471页

作者： Qiang SUN Yongling BAN Jun hu School of Electronic Science and Engineering University of Electronic Science and Technology of China

Exploring the multifunctional array antenna suitable for complex communication environment has very important research value. In this paper, a millimeter wave(mm-wave) double longitudinal sawtooth slot array antenna(DLSA) based on substrate integrated waveguide(SIW) technology is proposed, which has wideband, highgain and novel beam characteristics. Two irregular longitudinal slots are etched on the SIW conductor surface as the radiation structure. To improve the bandwidth of the DLSA, the metallized vias are added at the transition point of the slots to construct multiple resonant frequency points. By adjusting the size of the slots and the position of the metallized vias, the phase constant can be regulated, and the unusual beam characteristics can be obtained. That is to say, in the lower frequency band, the beam pointing angle increases with frequency. In the higher frequency band,the beam pointing angle is maintained at a fixed angle. Finally, to improve the antenna gain, a 16 × 8 DLSA is fabricated, measured and discussed. The proposed antenna has an impedance matching bandwidth close to 9.7 *** 27 to 33 GHz, the beam pointing angle changes from 8° to 29°. From 33 to 37 GHz, the beam pointing angle is fixed at 29°, and the pointing angle error range is ±1°. In addition, the measured maximum gain is 22.9 d Bi at32 GHz.

关键词： Antenna measurements Slot antennas Surface waves Resonant frequency Gain measurement Conductors Frequency measurement

A Hybrid Coupled Ocean–Atmosphere Model and Its Simulation of ENSO and Atmospheric Responses

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Advances in Atmospheric Sciences 2019年第6期36卷 643-657页

作者： Junya hu Rong-hua ZHANG Chuan GAO Chinese Academy of Sciences Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences Pilot National Laboratory for Marine Science and Technology Center for Ocean Mega-Science Chinese Academy of Sciences University of Chinese Academy of Sciences

A new hybrid coupled model(HCM) is presented in this study, which consists of an intermediate tropical Pacific Ocean model and a global atmospheric general circulation model. The ocean component is the intermediate ocean model(IOM)of the intermediate coupled model(ICM) used at the Institute of Oceanology, Chinese Academy of Sciences(IOCAS). The atmospheric component is ECHAM5, the fifth version of the Max Planck Institute for Meteorology atmospheric general circulation model. The HCM integrates its atmospheric and oceanic components by using an anomaly coupling strategy. A100-year simulation has been made with the HCM and its simulation skills are evaluated, including the interannual variability of SST over the tropical Pacific and the ENSO-related responses of the global atmosphere. The model shows irregular occurrence of ENSO events with a spectral range between two and five years. The amplitude and lifetime of ENSO events and the annual phase-locking of SST anomalies are also reproduced realistically. Despite the slightly stronger variance of SST anomalies over the central Pacific than observed in the HCM, the patterns of atmospheric anomalies related to ENSO,such as sea level pressure, temperature and precipitation, are in broad agreement with observations. Therefore, this model can not only simulate the ENSO variability, but also reproduce the global atmospheric variability associated with ENSO, thereby providing a useful modeling tool for ENSO studies. Further model applications of ENSO modulations by ocean–atmosphere processes, and of ENSO-related climate prediction, are also discussed.

关键词： IOCAS ICM hybrid coupled model ENSO simulation atmospheric response

Holography,UV/IR Relation,Causal Entropy Bound,and Dark Energy

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Communications in Theoretical Physics 2009年第5期51卷 954-960页

作者： CAI Rong-Gen hu Bin ZHANG Yi Institute of Theoretical Physics Chinese Academy of Sciences P.O. Box 2735 Beijing 100190 China

The constraint on the total energy in a given spatial region is given from holography by the mass of a black hole that just fits in that region, which leads to an UV/IR relation： the maximal energy density in that region is proportional to Mp^2/L^2, where Mp is the Planck mass and L is the spatial scale of that region under consideration. Assuming the maximal black hole in the universe is formed through gravitational collapse of perturbations in the universe, then the ＂Jeans＂ scale of the perturbations gives a causal connection scale RCC. For gravitational perturbations, RCC^-2= Max （H＋ 2H^2, -H） for a fiat universe. We study the cosmological dynamics of the corresponding vacuum energy density by choosing the causal connection scale as the IR cutoff in the UV/IR relation, in the cases of the vacuum energy density as an independently conserved energy component and an effective dynamical cosmological constant, respectively. It turns out that only the case with the choice RCC^-2 = H＋ 2H^2, could be consistent with the current cosmological observations when the vacuum density appears as an independently conserved energy component. In this case, the model is called holographic Ricci scalar dark energy model in the literature.

关键词： holography of gravity dark energy and cosmology

Systematic differences in position and proper-motion between the PPMX and UCAC3 catalogs

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Research in Astronomy and Astrophysics 2011年第9期11卷 1074-1084页

作者： Jia-Cheng Liu Zi Zhu Bo hu Department of Astronomy Nanjing University Nanjing 210093 China Key Laboratory of Modern Astronomy and Astrophysics （Nanjing University） Ministry of Education Nanjing 210093 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Considered to be extensions of the Hipparcos reference system, PPMX and UCAC3 are two of the most important astrometric catalogs released in current years. Extensive analyses of these two large catalogs have been made in order to determine the local and overall systematic biases. The regional and magnitude dependent differences in stellar position and proper motion are comparable to random errors and are even larger in the northern hemisphere. The global orientation bias vector ε between the two systems is also significant （up to 17 mas）, which shows the overall differences of the PPMX and UCAC3 catalogs and their reference systems. On the other hand, the term for the global rotation vector a; is small （tenths of mas per year）： it is reasonable to believe that the PPMX and UCAC3 reference frames do not rotate with respect to each other. Because of plate dependent and field-to-field errors in the UCAC3 catalog, we suggest that positions and proper motions of UCAC3 stars in the northern hemisphere （δ 〉 -20°） should be used with caution.

关键词： astrometry -- catalogs -- reference systems

Multi-arm covariate-adaptive randomization

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Science China Mathematics 2023年第1期66卷 163-190页

作者： Feifang hu Xiaoqing Ye Li-Xin Zhang Department of Statistics The George Washington UniversityWashingtonDC 20052USA Institute of Statistics and Big Data Renmin University of ChinaBeijing 100872China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China

Simultaneously investigating multiple treatments in a single study achieves considerable efficiency in contrast to the traditional two-arm *** treatment allocation for influential covariates has become increasingly important in today’s clinical *** multi-arm covariate-adaptive randomized clinical trial is one of the most powerful tools to incorporate covariate information and multiple treatments in a single *** and Simon’s procedure has been extended to the multi-arm ***,the theoretical properties of multi-arm covariate-adaptive randomization have remained largely elusive for *** this paper,we propose a general framework for multi-arm covariate-adaptive designs which also includes the two-arm case,and establish the corresponding theory under widely satisfied *** theoretical results provide new insights into the balance properties of covariate-adaptive randomization procedures and make foundations for most existing statistical inferences under two-arm covariate-adaptive ***,these open a door to study the theoretical properties of statistical inferences for clinical trials based on multi-arm covariateadaptive randomization procedures.

关键词： multiple treatment balancing covariate clinical trial marginal balance Markov chain hu and hu’s general procedure Pocock and Simon’s procedure stratified permuted block design

局部麻醉下机器人辅助经皮椎体后凸成形伤椎注入骨水泥的患者体验分析

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中国组织工程研究 2025年第22期29卷 4647-4652页

作者：李佳鸿林书唐六一胡豇俞阳张伟四川省医学科学院·四川省人民医院(电子科技大学附属医院)骨科四川省成都市610072

背景:局部麻醉下传统C臂辅助经皮椎体后凸成形手术需多次透视以调整穿刺方向,工作通道建立时间较长,患者术中疼痛刺激较大;而机器人辅助经皮椎体后凸成形手术可一次性精准穿刺成功,明显改善患者术中体验,同时减少骨水泥渗漏风险。目的:... 详细信息

背景:局部麻醉下传统C臂辅助经皮椎体后凸成形手术需多次透视以调整穿刺方向,工作通道建立时间较长,患者术中疼痛刺激较大;而机器人辅助经皮椎体后凸成形手术可一次性精准穿刺成功,明显改善患者术中体验,同时减少骨水泥渗漏风险。目的:比较局部麻醉下机器人辅助和传统C臂辅助经皮椎体后凸成形手术的患者体验和其他疗效。方法:选择四川省医学科学院·四川省人民医院(电子科技大学附属医院)收治的单节段骨质疏松性椎体压缩骨折患者241例,其中132例在局部麻醉下进行机器人辅助经皮椎体后凸成形手术治疗(机器人辅助组),109例在局部麻醉下进行传统C臂辅助经皮椎体后凸成形手术治疗(传统透视组),记录患者术中体验评价、骨水泥注射量、手术时间、工作通道建立时间、住院费用及并发症,术后1 d通过影像学评估穿刺偏差与骨水泥渗漏。结果与结论:(1)机器人组59例患者术中体验评价为“非常好”,43例为“好”,16例为“一般”,10例为“差”,4例为“非常差”;传统透视组30例患者术中体验评价为“非常好”,44例为“好”,21例为“一般”,9例为“差”,5例为“非常差”,两组间术中体验评价比较差异有显著性意义(Z=-2.546,P=0.011);机器人组患者术中目测类比评分低于传统透视组(t=-9.513,P=0.000);机器人组、传统透视组愿意在必要时再次接受经皮椎体后凸成形手术的患者分别为84例和47例,组间比较差异有显著性意义(Z=-2.730,P=0.006);(2)机器人组患者手术时间、住院费用均多于传统透视组(t=2.860,P=0.003;t=36.522,P=0.000),工作通道建立时间短于传统透视组(t=-27.066,P=0.000),穿刺精度优于传统透视组(Z=-3.656,P=0.000),骨水泥渗漏率低于传统透视组(χ^(2)=7.284,P=0.007);(3)结果表明,局部麻醉后在机器人辅助行经皮椎体后凸成形手术患者的手术体验较好,具有穿刺精确、工作通道建立时间短、骨水泥渗漏率低的优势。

关键词：机器人骨质疏松性椎体压缩骨折经皮椎体后凸成形患者体验局部麻醉

Epigenetic control on cell fate choice in neural stem cells

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Protein & Cell 2012年第4期3卷 278-290页

作者： Xiao-Ling hu Yuping Wang Qin Shen Center for Stem Cell Biology and Regenerative Medicine School of MedicineTsinghua Center for Life SciencesTsinghua UniversityBeijing 100084China Department of Pharmacy Tianjin Children’s HospitalTianjin 300074China

Derived from neural stem cells(NSCs)and progenitor cells originated from the neuroectoderm,the nervous system presents an unprecedented degree of cellular diversity,interwoven to ensure correct connections for propagating information and responding to environ-mental *** and progenitor cells must integrate cell-intrinsic programs and environmental cues to achieve production of appropriate types of neurons and glia at appropriate times and places during *** developmental dynamics are reflected in changes in gene expression,which is regulated by transcription factors and at the epigenetic *** early commitment of neural lineage to functional plas-ticity in terminal differentiated neurons,epigenetic regulation is involved in every step of neural *** we focus on the recent advance in our un-derstanding of epigenetic regulation on orderly genera-tion of diverse neural cell types in the mammalian nervous system,an important aspect of neural devel-opment and regenerative medicine.

关键词： neural stem cells(NSCs) epigenetic regu-lation neurogenesis gliogenesis radial glial cell cerebral cortex subventricular zone(SVZ) DNA methylation histone modification

Is the Limit of Four Times the Primary Interest Rate of Loan Reasonable

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当代财经 2013年第S1期 57-68页

作者： hu Yuan-cheng Jiangxi University of Finance and Economics Research Center for Financial Development and Risk Prevention

On the basis of the observation of the real earnings rates and the debt repayment ability of China’s enterprises,considering the maintenance of the normal order of the borrowing and lending markets,this paper believes that a 20 percent level of interest rate or rate of return is a suitable cutoff point for the up limit,which is in line with China’s *** this reason,we recommend that the primary interest rate of three times of the loan should be adopted to determine the up limit of annual rate of private borrowing and lending allowed by policy,this is relatively consistent with China’s current reality.

关键词： private borrowing and lending primary interest rate return on assets debt repayment ability

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复合型小细胞肺癌研究进展

解放军医学杂志 2018年第9期43卷 799-805页

作者：李涛张娟胡毅北京解放军总医院肿瘤内科、全军肿瘤学重点实验室、肿瘤靶向治疗和抗体药物教育部重点实验室 100853 解放军总医院/解放军医学院研究生管理大队北京100853

随着对小细胞肺癌认识和研究的不断深入,人们逐渐发现和揭示了一种病理类型为小细胞肺癌混合非小细胞肺癌成分的疾病,即复合型小细胞肺癌(C-SCLC)。与单纯型小细胞肺癌相比,C-SCLC无论在发生机制与起源、临床生物学特性,还是在治疗和疾... 详细信息

随着对小细胞肺癌认识和研究的不断深入,人们逐渐发现和揭示了一种病理类型为小细胞肺癌混合非小细胞肺癌成分的疾病,即复合型小细胞肺癌(C-SCLC)。与单纯型小细胞肺癌相比,C-SCLC无论在发生机制与起源、临床生物学特性,还是在治疗和疾病预后等诸多方面都与之既有联系又有区别。基础研究的不断深入促进了C-SCLC来源、机制、起病等多方面的研究进展。随着医疗技术和诊疗手段的发展,临床上对于C-SCLC的发现和诊断率不断提高,治疗上也取得了一定效果。本文对目前C-SCLC的研究进展、诊断与分期、治疗现状和预后等进行归纳,以为今后进一步的基础科研探索和临床治疗提供经验。

关键词：小细胞肺癌,复合型治疗,预后