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Design and Cryogenic Performance of a Hexapod Platform for a Large Ground-based Wide Field Survey Telescope

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Research in Astronomy and Astrophysics 2024年第1期24卷 178-187页

作者： Yang Yu xue-Wen Wang Yu Zhang Jia-Lin Sun Zhen-bang xu Jian-Li Wang Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Chinese Academy of Sciences Key Laboratory of On-orbit Manufacturing and Integration for Space Optics System Changchun 130033China University of Chinese Academy of Sciences Beijing 100049China

The thermal gradient is an important factor that causes degradation to the image quality of telescopes. In order to ensure the accurate alignment of the primary focus unit and the primary mirror, the hexapod platform(as a corrector) is investigated in this paper. First, a ground-based telescope with 2.5 m aperture and 3.5 deg field of view is described. The telescope is under construction, and it is expected to be finished in 2023. Second, the hexapod platform with flexure hinges utilized to adjust the primary focus unit is proposed, which is applied as a ***, the inverse kinematics of the platform is established and an open-loop control system is built based on ***, the cryogenic performance test for the hexapod platform is performed. The experimental results show that the resolution and repeatability of the translation for the hexapod platform can be achieved at the micrometer *** resolution and repeatability of the rotation can be achieved at the arc-second level. Therefore, the cryogenic performance of the hexapod platform can meet the optical imaging requirements of the wide-field ground-based telescope. The kinematic analysis and cryogenic performance tests in the paper provide a technical reference for the precise alignment of the primary focus unit and the primary mirror, which can improve the imaging quality of the telescope.

关键词： methods:miscellaneous space vehicles:instruments telescopes miscellaneous

SARS-CoV-2 envelope protein impairs airway epithelial barrier function and exacerbates airway inflammation via increased intracellular Cl^(-)concentration

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1745-1759页

作者： Jian-bang xu Wei-Jie Guan Yi-Lin Zhang Zhuo-Er Qiu Lei Chen Xiao-Chun Hou Junqing Yue Yu-Yun Zhou Jie Sheng Lei Zhao Yun-Xin Zhu Jing Sun Jincun Zhao Wen-Liang Zhou Nan-Shan Zhong State Key Laboratory of Respiratory Disease National Clinical Research Center for Respiratory DiseaseNational Center for Respiratory MedicineDepartment of Respiratory and Critical Care MedicineGuangzhou Institute of Respiratory HealthThe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouP.R.China Department of Thoracic Surgery Guangzhou Institute for Respiratory HealthThe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouP.R.China Guangzhou National Laboratory GuangzhouP.R.China School of Life Sciences Sun Yat-sen UniversityGuangzhouP.R.China Guangdong Provincial Key Laboratory of Pharmaceutical Functional Genes School of Life SciencesSun Yat-sen UniversityGuangzhouP.R.China Department of Physiology School of Basic Medical SciencesGuangzhou Medical UniversityGuangzhouP.R.China

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection disrupts the epithelial barrier and triggers airway *** envelope(E)protein,a core virulence structural component of coronaviruses,may play a role in this *** could interfere with transepithelial Cl^(-)transport via impairment of the cystic fibrosis transmembrane conductance regulator(CFTR),which modulates nuclear factor kB(NF-kB)***,the pathological effects of SARS-CoV-2 E protein on airway epithelial barrier function,Cl^(-)transport and the robust inflammatory response remain to be ***,we have demonstrated that E protein down-regulated the expression of tight junctional proteins,leading to the disruption of the airway epithelial *** addition,E protein triggered the activation of Toll-like receptor(TLR)2/4 and downstream c-Jun N-terminal kinase(JNK)signaling,resulting in an increased intracellular Cl^(-)concentration([Cl^(-)]_(i))via up-regulating phosphodiesterase 4D(PDE4D)expression in airway epithelial *** elevated[Cl^(-)]_(i);contributed to the heightened airway inflammation through promoting the phosphorylation of serum/glucocorticoid regulated kinase 1(SGK1).Moreover,blockade of SGK1 or PDE4 alleviated the robust inflammatory response induced by E ***,these findings provide novel insights into the pathogenic role of SARS-CoV-2 E protein in airway epithelial damage and the ongoing airway inflammation during SARS-CoV-2 infection.

关键词： airway inflammation elevated

基于DRNN-LSTM-IPSO的锅炉经济运行优化目标值

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科学技术与工程 2024年第7期24卷 2749-2758页

作者：钱虹王海心徐邦智上海电力大学自动化工程学院上海200090 上海市电站自动化技术重点实验室上海200072

锅炉作为火电厂的重要设备,提高其运行经济性直接影响电厂的生产效益,而锅炉运行参数优化目标值的合理确定是保障锅炉经济运行的关键。首先提出改进的高斯混合模型算法应用于工况划分,即通过划分数据的分散度作为依据并基于马氏距离来... 详细信息

锅炉作为火电厂的重要设备,提高其运行经济性直接影响电厂的生产效益,而锅炉运行参数优化目标值的合理确定是保障锅炉经济运行的关键。首先提出改进的高斯混合模型算法应用于工况划分,即通过划分数据的分散度作为依据并基于马氏距离来构建评价准则函数,以确定聚类数;其次通过构建具备长短时记忆功能的深度循环神经网络(deep recurrent neural network with long-short term memory, DRNN-LSTM)建立各工况区间下的经济模型;最后在经济模型构建的基础上,针对传统粒子群算法容易陷入局部极值问题,通过对惯性权重和加速因子进行调整得到改进的粒子群算法(improved particle swarm optimization, IPSO),可更加精准地在不同工况下进行区间范围内寻优,确定运行参数的优化目标值。实验结果表明,采用本文方法确定的优化目标值对应供电煤耗优于历史最优运行值,说明了该方法在挖掘锅炉优化运行潜力上具有一定的优势,按此方案调整锅炉运行可有效降低能耗水平,以达到锅炉经济运行的目的。

关键词：工况划分改进的高斯混合模型 DRNN-LSTM IPSO 优化目标值

Non-interactive automatic video segmentation of moving targets

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第10期13卷 736-749页

作者： Yu ZHOU An-wen SHEN Jin-bang xu Department of Control Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Extracting moving targets from video accurately is of great significance in the field of intelligent *** some extent,it is related to video segmentation or *** this paper,we propose a non-interactive automatic segmentation method for extracting moving ***,the motion knowledge in video is detected with orthogonal Gaussian-Hermite moments and the Otsu algorithm,and the knowledge is treated as foreground ***,the background seeds are generated with distance transformation based on foreground ***,the foreground and background seeds are treated as extra constraints,and then a mask is generated using graph cuts methods or closed-form *** showed that the closed-form solution based on soft segmentation has a better performance and that the extra constraint has a larger impact on the result than other *** demonstrated that the proposed method can effectively extract moving targets from video in real time.

关键词： Video segmentation Auto-generated seeds Cost function Alpha matte

瓦尼桑黄固体发酵产物的化学成分及其生物活性研究

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天然产物研究与开发 2024年第4期36卷 607-615页

作者：吴椰高鹤萍毛燕妍黄明慧徐帮邹坤刘呈雄汪蕾三峡大学生物与制药学院天然产物研究与利用湖北省重点实验室(中国轻工业功能酵母重点实验室) 三峡大学第一临床医学院宜昌443002

对瓦尼桑黄(Sanghuangporus vaninii)固体发酵产物的化学成分及生物活性进行研究。采用超声提取、柱层析以及半制备高效液相色谱等方法分离纯化,通过波谱数据鉴定了化合物的结构,并对所得单体化合物进行体外抗氧化活性、α-葡萄糖苷酶... 详细信息

对瓦尼桑黄(Sanghuangporus vaninii)固体发酵产物的化学成分及生物活性进行研究。采用超声提取、柱层析以及半制备高效液相色谱等方法分离纯化,通过波谱数据鉴定了化合物的结构,并对所得单体化合物进行体外抗氧化活性、α-葡萄糖苷酶和黄嘌呤氧化酶抑制活性筛选。从瓦尼桑黄固体发酵产物中分离得到17个化合物,分别为(2Z,4E)-γ-ionylideneacetic acid(1)、phellinulin E(2)、phellinulin F(3)、phellinulin G(4)、phellinulin J(5)、phellinulin L(6)、phellinulin M(7)、phellinulin N(8)、elgonenes D(9)、咖啡酸(10)、hispidin(11)、3-hydroxyhispidin(12)、原儿茶酸(13)、4-(3-ethoxy-4-hydroxyphenyl)but-3-en-2-one(14)、丁子香酚(15)、亚油酸甲酯(16)、硬脂酸(17),其中化合物1~9为首次从瓦尼桑黄中分离得到。活性测试结果显示化合物10~13表现出良好的抗氧化活性,对DPPH自由基的半数抑制浓度(IC_(50))分别为16.45、37.52、82.71、50.46μg/mL,对ABTS自由基的IC_(50)值分别为1.43、2.26、34.55、21.60μg/mL,对羟基自由基的IC_(50)值分别为38.43、49.46、86.74、69.16μg/mL。化合物10、11还对黄嘌呤氧化酶表现出良好的抑制作用,IC_(50)值分别为28.73和44.80μg/mL。化合物17具有一定的α-葡萄糖苷酶抑制活性,其IC_(50)值2.31μg/mL。

关键词：瓦尼桑黄化学成分体外抗氧化活性 α-葡萄糖苷酶黄嘌呤氧化酶

Virtual channel load-balanced routing algorithm for Torus networks

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The Journal of China Universities of Posts and Telecommunications 2011年第1期18卷 70-76页

作者： WANG Ya-gang DU Hui-min SHEN xu-bang School of Computer Xidian University Xi'an 710071 China School of Computer Xi'an University of Posts and Telecommunications Xi'an 710121 China School of Electronic Engineering Xi'an University of Posts and Telecommunications Xi'an 710121 China

In order to improve the network performance furthermore, a routing algorithm for 2D-Torus is investigated from the standpoint of load balance for virtual channels. The 2D-Torus network is divided into two virtual networks and each physical channel is split into three virtual channels. A novel virtual channel allocation policy and a routing algorithm are proposed, in which traffic load is distributed to those three virtual channels in a more load-balanced manner by introducing a random parameter. Simulations of the proposed algorithm are developed with a SystemC-based test bench. The results show that compared with the negative first for Torus networks （NF-T） algorithm, the proposed algorithm can achieve better performance in terms of network latency and throughput under different traffic patterns. It also shows that a routing algorithm with load balance for virtual channels can significantly improve the network performance furthermore.

关键词： interconnection network Torus networks routing algorithm virtual channel load balance

Topological properties and routing algorithm for semi-diagonal torus networks

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The Journal of China Universities of Posts and Telecommunications 2011年第5期18卷 64-70页

作者： WANG Ya-gang DU Hui-min SHEN xu-bang School of Computer Xidian University Xi＇an 710071 China School of Electronic Engineering Xi＇an University of Posts and Telecommunications Xi＇an 710121 China

To improve the scalability and reduce the implementation complexity of Mesh and Mesh-like networks, the semi-diagonal Torus （SD-Torus） network, a regular and symmetrical intercormection network is proposed. The SD-Torus network is a combination of a typical 2D-Torus network with two extra diagonal links from northwest to southeast direction for each node. The topological properties of SD-Torus networks are discussed, and a load balanced routing algorithm for SD-Torus is presented. System-C based simulation result shows that, compared with diagonal Mesh （DMesh）, diagonal Torus （DTorus） and XMesh networks, the SD-Torus network can achieve high performance with a lower network cost. It makes the SD-Torus network a powerful candidate for the high performance interconnection networks.

关键词： interconnection networks routing algorithm load balance SD-Toms networks direct networks

华泽兰内生真菌Aspergillus puniceus次级代谢产物及其抗三阴性乳腺癌活性和作用机制

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华中师范大学学报（自然科学版） 2024年第2期58卷 206-213页

作者：魏敏陈莲陈剑锋金桂兰徐帮王倩邹坤程凡刘呈雄三峡大学生物与制药学院天然产物研究与利用湖北省重点实验室湖北宜昌443002 宜昌市第一人民医院三峡大学附属人民医院湖北宜昌443002 宜昌人福药业有限责任公司湖北宜昌443002

从华泽兰根部分离得到一株内生真菌Aspergillus puniceus.采用正相硅胶柱色谱、Sephadex LH-20凝胶柱色谱及半制备高效液相色谱等方法,从该菌株的发酵液中分离得到8个结构类似的口山酮类化合物,通过现代波谱技术分别鉴定为3′,4′-hydro... 详细信息

从华泽兰根部分离得到一株内生真菌Aspergillus puniceus.采用正相硅胶柱色谱、Sephadex LH-20凝胶柱色谱及半制备高效液相色谱等方法,从该菌株的发酵液中分离得到8个结构类似的口山酮类化合物,通过现代波谱技术分别鉴定为3′,4′-hydrogenated austocystins A(1)、austocystin M(2)、austocystin F(3)、austocystin D(4)、austocystin B(5)、austocystin K(6)、austocystin A(7)、austocystin H(8).MTT结果显示化合物5对三阴性乳腺癌MDA-MB-231细胞具有较好的选择性细胞毒活性(IC_(50)为1.28μmol·L^(-1)).另外,流式细胞术检测化合物5作用于MDA-MB-231细胞后凋亡率的变化,相比于对照组,最高总凋亡率为69.7%.同时,AO/EB双荧光染色也证明化合物5能够诱导MDA-MB-231的细胞凋亡.JC-1线粒体膜电位检测进一步显示化合物5能够通过线粒体途径诱导三阴性乳腺癌MDA-MB-231的细胞凋亡.

关键词：华泽兰 Aspergillus puniceus 次级代谢产物口山酮三阴性乳腺癌凋亡

Design and optimization for multiprocessor interactive GPU

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The Journal of China Universities of Posts and Telecommunications 2014年第3期21卷 85-97页

作者： DENG Jun-yong LI Tao JIANG Lin HAN Jun-gang SHEN xu-bang School of Micro-electronics Xidian University School of Electronic Engineering Xi’an University of Posts and Telecommunications

In order to achieve maximization of parallelism, effective distribution of rendering tasks, balance between performance and flexibility in graphics processing pipeline, this article presents design, performance analysis and optimization for multi-core interactive graphics processing unit （MIGPU）. This processor integrates twelve processing cores with specific instruction set architecture and many sophisticated application-specific accelerators into a 3D graphics engine. It is implemented on XC6VLX550T field programmable gate array （FPGA）. MIGPU supports OpenGL2.0 with programmable front-end processor, vertex shader, plane clipper, geometry transformer, three-D clippers and pixel shaders. For boosting the performance of MIGPU, the relationship model is established between primitive types, vertices, pixels, and the effect of culling, clipping, and memory access, and shows a way to improve the speed up of the graphics pipeline. It is capable of assigning graphics rendering tasks to different processors for efficiency and flexibility. The pixel filling rate can reach to 40 Mpixel/s at its peak performance.

关键词： multiprocessor graphics processing unit (GPU) performance optimization parallelism