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Interventional endoscopic ultrasound for a symptomatic pseudocyst secondary to gastric heterotopic pancreas

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World Journal of Gastroenterology 2017年第34期23卷 6365-6370页

作者： hang-bin jin lei lu jian-feng yang qi-feng lou jing yang hong-zhang shen xiao-wei tang xiao-feng zhang Department of Gastroenterology Hangzhou First People’s HospitalNanjing Medical University

Heterotopic pancreas(HP) is a relatively uncommon entity that is defined as pancreatic tissue without a true anatomical or vascular connection to the pancreas. HP does not cause symptoms in most cases but can occasionally produce various manifestations, including nausea, vomiting, abdominal pain, and even heterotopic pancreatitis. Here, we report an unusual case in which heterotopic pancreatitis complicated by the formation of a pseudocyst that caused gastric outlet obstruction was diagnosed based on serum hyperamylasemia and findings from endoscopic ultrasonography(EUS)-guided fine needle aspiration(EUS-FNA) cytology. EUS-guided single pigtail stent insertion was successfully performed for recurrent gastric outlet obstruction. The patient has remained healthy and symptom-free during 4 years of surveillance. In the context of the relevant literature, the described case is a rare case of HP complicated by a pseudocyst treated via EUS-FNA and stent insertion.

关键词： Heterotopic pancreas Pseudocyst gastric outlet obstruction Endoscopic ultrasound-guided fine needle aspiration

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浙江省小水电流域规划与实践

水利水电技术 2000年第7期31卷 44-46页

作者：楼琦浙江省水电开发管理中心杭州市310009

通过对浙江省小水电建设历程的回顾 ,总结出该省小水电流域规划成功的主要经验在于 :(1 )注重小流域的梯级开发 ;(2 )重视龙头水库在流域规划中的运用 ;(3 )采用“集水网道”引水入库 ;(4 )优先开发有径流调节的电站 ,并适当加大装机容量 .

关键词：流域规划小水电实践浙江

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浙江省农村水电建设实践与发展研究

水利水电技术 2007年第4期38卷 58-60页

作者：楼琦浙江省水利厅浙江杭州310009

分析、研究了浙江省农村水电“九五”、“十五”股份制投资开发建设农村水电,“资源、生态、经济”三大补偿制度的建立和发展,以及各时期水电建设的工程技术特点;论述了“十一五”浙江水电的发展思路及建设方向。阐述了制度建设与水电... 详细信息

分析、研究了浙江省农村水电“九五”、“十五”股份制投资开发建设农村水电,“资源、生态、经济”三大补偿制度的建立和发展,以及各时期水电建设的工程技术特点;论述了“十一五”浙江水电的发展思路及建设方向。阐述了制度建设与水电技术发展相互制约、相互促进的辩证关系,认为制度建设是农村水电建设发展的基础和助推器。

关键词：农村水电建设发展研究浙江省

The Improved Power of the Central Lobe in the Beam Combination and High Power Output

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Chinese Physics Letters 2012年第4期29卷 82-85页

作者： LIU Hou-Kang XUE Yu-Hao LI Zhen HE Bing ZHOU Jun DING Ya-qian JIAO Meng-Li LIU Chi qi Yun-Feng WEI Yun-Rong DONG Jing-Xing lou qi-Hong Shanghai Key Laboratory of All Solid-State Laser and Applied Techniques Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800 Graduate University of Chinese Academy of Sciences Beijing 100049

In order to increase the power fraction of the central lobe in the coherent beam combination of lasers in an array,the effects of the distance factor of near-field distribution on far-field interference patterns are calculated and demonstrated *** improved beam array of interwoven distribution is demonstrated to enable the power in the central lobe to reach 41%.An optimized mirror array is carefully designed to obtain a high duty ratio,which is up to 53.3% at a high power *** using these optimized methods and designs,the passive phase locking of eight Yb-doped fiber amplifiers with ring cavities are obtained,and a pleasing interference pattern with 87% visibility is *** maximum coherent output power of the system is up to 1066 W.

关键词： passive fiber coherent

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板柱结构矩形弹性板弯曲精确解法

工程力学 2006年第3期23卷 76-81页

作者：许琪楼王海郑州大学土木工程学院郑州450002 河南省水利科学研究所郑州450003

板柱结构是工程中经常采用的受力体系,但至今尚无一种精确解法分析板中内力分布。将板柱结构矩形板的弯曲划分为广义静定和广义超静定二类。对于前者利用静力平衡条件确定柱支反力后撤去柱支座,柱支条件下板的弯曲即转换为四边自由矩形... 详细信息

板柱结构是工程中经常采用的受力体系,但至今尚无一种精确解法分析板中内力分布。将板柱结构矩形板的弯曲划分为广义静定和广义超静定二类。对于前者利用静力平衡条件确定柱支反力后撤去柱支座,柱支条件下板的弯曲即转换为四边自由矩形板在原荷载和柱支反力共同作用下的弯曲。挠度表达式采用了新的通解形式,其变形曲线符合四边自由边界所限定的变形特征,并采用组合特解,即特解同时满足平衡微分方程,自由边界上剪力分布条件及自由角点上作用力条件,从而可以利用四边边界条件和柱支座处的位移条件直接求解。对于广义超静定弯曲需要利用叠加法求解。这种解法可以分析板柱结构在任意柱支条件下和任意荷载作用下板的弯曲。通过逆向分析验证法真实地说明了本解法具有很高的计算精度。

关键词：板柱结构弹性板弯曲矩形板精确解法逆向分析验证

Highly efficient room temperature phosphorescent liquid crystalline polymer optical waveguides for advanced optoelectronics

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Science China Chemistry 2024年第10期67卷 3450-3457页

作者： Jie Li Yan Guan Wei Xia Jin-Kang Chen Jiang Huang Yi Chen qi Lin Er-qiang Chen He-lou Xie Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education and Key Laboratory of Advanced Functional Polymer Materials of CollegesUniversities of Hunan Province and College of ChemistryXiangtan UniversityXiangtan 411105China School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Active organic optical waveguide materials(OOWMs)incorporating room temperature phosphorescence(RTP)hold significant promise for diverse applications in photonic and optoelectronic *** this potential,realizing active RTP optical waveguides with large-sized ordered structures and minimal light loss remains a formidable *** address this issue,we present a groundbreaking thermoplastic active OOWM with low light loss,leveraging room temperature phosphorescent liquid crystalline polymer(LCP).This innovative material can be easily synthesized through the copolymerization of phosphorescent and liquid crystalline *** resulting RTP copolymer exhibits a nematic liquid crystal phase with a phosphorescence lifetime of approximately 0.15 ms and an afterglow duration of around 1 *** the excellent processability of LCP,we successfully produce meter-scale fibers via melt *** RTP LCP fibers,characterized by a high orientation of mesogens along the fiber axis,demonstrate superior light confinement and efficient light conduction compared to unoriented samples,resulting in a low optical loss coefficient of 0.13 dB/***,the thermal responsiveness of the RTP LCP optical waveguide enables its use as a photo *** pioneering work paves the way for the design of new OOWMs tailored for advanced photonics and optoelectronics devices.

关键词： room temperature phosphorescence liquid crystalline polymer active optical waveguide

Autonomously Tuning Multilayer Thermal Cloak with Variable Thermal Conductivity Based on Thermal Triggered Dual Phase-Transition Metamaterial

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Chinese Physics Letters 2023年第9期40卷 54-60页

作者：娄琦夏明岗 Department of Applied Physics School of PhysicsXi’an Jiaotong UniversityXi’an 710049China MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter School of PhysicsXi’an Jiaotong UniversityXi’an 710049China Shaanxi Province Key Laboratory of Quantum Information and Optoelectronic Quantum Devices School of PhysicsXi’an Jiaotong UniversityXi’an 710049China

Thermal cloaks offer the potential to conceal internal objects from detection or to prevent thermal shock by controlling external heat flow. However, most conventional natural materials lack the desired flexibility and versatility required for on-demand thermal manipulation. We propose a solution in the form of homogeneous multilayer thermodynamic cloaks. Through an ingenious design, these cloaks achieve exceptional and extreme parameters, enabling the distribution of multiple materials in space. We first investigate the effects of important design parameters on the thermal shielding effectiveness of conventional thermal cloaks. Subsequently, we introduce an autonomous tuning function for the thermodynamic cloak, accomplished by leveraging two phase transition materials as thermal conductive layers. Remarkably, this tuning function does not require any energy input. Finite element analysis results demonstrate a significant reduction in the temperature gradient inside the thermal cloak compared to the surrounding background. This reduction indicates the cloak’s remarkable ability to manipulate the spatial thermal field. Furthermore, the utilization of materials undergoing phase transition leads to an increase in thermal conductivity, enabling the cloak to achieve the opposite variation of the temperature field between the object region and the background. This means that, while the temperature gradient within the cloak decreases, the temperature gradient in the background increases. This work addresses a compelling and crucial challenge in the realm of thermal metamaterials, i.e., autonomous tuning of the thermal field without energy input. Such an achievement is currently unattainable with existing natural materials. This study establishes the groundwork for the application of thermal metamaterials in thermodynamic cloaks, with potential extensions into thermal energy harvesting, thermal camouflage, and thermoelectric conversion *** harnessing phonons, our fi

关键词： thermodynamic autonomous Transition

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城市轨道交通联锁系统发展趋势分析

城市轨道交通研究 2021年第11期24卷 18-22页

作者：娄琦上海申通地铁集团有限公司上海201103

城市轨道交通信号的联锁系统是保障列车运行安全的核心设备,根据安全防护条件和时序实现进路、信号和道岔之间联锁控制,满足列车安全运行的需求。分析了在大客流、高密度及超大网络的形势下,联锁系统作为信号系统安全最后一道防线所面... 详细信息

城市轨道交通信号的联锁系统是保障列车运行安全的核心设备,根据安全防护条件和时序实现进路、信号和道岔之间联锁控制,满足列车安全运行的需求。分析了在大客流、高密度及超大网络的形势下,联锁系统作为信号系统安全最后一道防线所面临的发展需求。基于安全防护机理,结合当前信号系统故障-安全-持续运行的发展方向,从联锁系统的安全-效率平衡、全自动化运行适配及互联互通等方面分析了联锁系统的未来发展趋势。从联锁系统的安全理念、功能、形式和控制方式等方面阐述其演变要求,即:从“小联锁”向“大联锁”转变,从“硬联锁”向“软联锁”转变。

关键词：城市轨道交通联锁系统发展趋势

旅客自动运输系统(APM)全自动驾驶应用解析

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城市轨道交通研究 2016年第B8期19卷 16-20页

作者：娄琦上海申通地铁集团有限公司上海工程师201103

全自动无人驾驶系统使完全自动化计算机代替了驾驶员所有的工作,再配合综合监控系统和通信系统,可以使OCC(运营控制中心)调度员轻易地了解列车内所有的信息及列车状态。结合北京地铁APM(旅客自动运输)线、广州珠江APM线等无人驾驶线路,... 详细信息

全自动无人驾驶系统使完全自动化计算机代替了驾驶员所有的工作,再配合综合监控系统和通信系统,可以使OCC(运营控制中心)调度员轻易地了解列车内所有的信息及列车状态。结合北京地铁APM(旅客自动运输)线、广州珠江APM线等无人驾驶线路,介绍了APM的功能、特点、发展趋势,并从系统设计、运营模式、开关门时间等几个方面与地铁、轻轨等城市轨道交通系统进行了对比分析,提出现阶段APM系统适合中等运量、高密度运营需求的线路使用。

关键词：旅客自动运输系统全自动无人驾驶