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数字创新能力、技术创新效率与企业效益——数字创新环境的调节作用

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昆明理工大学学报（自然科学版） 2024年第1期49卷 165-179页

作者：郑季良石金慧昆明理工大学管理经济学院云南昆明650500

数字经济时代企业通过数字创新提高竞争力是必由路径.为深化对这一路径的理解,构建了企业数字创新能力的评价体系、数字创新能力—技术创新效率—企业效益的驱动机制模型,并考量数字创新环境的调节作用.收集了2014—2020年中国991家制... 详细信息

数字经济时代企业通过数字创新提高竞争力是必由路径.为深化对这一路径的理解,构建了企业数字创新能力的评价体系、数字创新能力—技术创新效率—企业效益的驱动机制模型,并考量数字创新环境的调节作用.收集了2014—2020年中国991家制造业上市公司的有关资料数据,对公司的数字创新能力进行了评价分析,对驱动机制模型进行了实证研究.结果显示:上市制造企业的数字创新能力呈现总体上升的趋势,但处于较低水平;数字创新能力对企业效益具有正向影响,技术创新效率在其中起到了部分中介的作用;数字创新环境(创新平台、创新文化)对数字创新能力—技术创新效率—企业效益的前后环节都具有正向调节作用,并加强了技术创新效率的中介效应.

关键词：数字创新能力技术创新效率企业效益数字经济

基于简易实频技术的宽带高效率功率放大器设计

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电子器件 2024年第3期47卷 610-616页

作者：石金辉王斌重庆邮电大学光电工程学院重庆400065

为了满足5G通信系统对功率放大器带宽和效率的要求,基于CGH40010F晶体管,采用简易实频技术,设计了一款工作在n77频段(3.3 GHz~4.2 GHz)的宽带高效率功率放大器。首先采用负载牵引的方法对各频点的基波最佳阻抗值以及二次谐波阻抗空间进... 详细信息

为了满足5G通信系统对功率放大器带宽和效率的要求,基于CGH40010F晶体管,采用简易实频技术,设计了一款工作在n77频段(3.3 GHz~4.2 GHz)的宽带高效率功率放大器。首先采用负载牵引的方法对各频点的基波最佳阻抗值以及二次谐波阻抗空间进行提取,选择简易实频技术设计宽带匹配网络,在其仿真性能良好的前提下,进行了加工测试。测试结果表明,该功率放大器在3.3 GHz~4.2 GHz频段内,漏极效率为58.1%~64.5%,增益为11.1 dB~12.9 dB,饱和输出功率为39.6 dBm~41.3 dBm。该功率放大器的性能良好,且带宽和效率具有一定的优势,可为后续宽带高效率功率放大器的设计提供参考。

关键词：功率放大器简易实频技术宽带高效率

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无人机电子设备舱热环境仿真分析

航天器环境工程 2024年第2期41卷 144-150页

作者：周忆梦梁世哲赵创新史金辉成都飞机工业(集团)有限责任公司成都610031

为满足无人机电子设备舱对舱内热环境的严苛要求,文章采用了有限体积法求解温度场的控制方程。根据无人机电子设备舱的材料结构特点和边界条件,应用FLUENT软件进行了设备舱的数值仿真分析;在此基础上提出了搭建支架的散热方案并对舱内... 详细信息

为满足无人机电子设备舱对舱内热环境的严苛要求,文章采用了有限体积法求解温度场的控制方程。根据无人机电子设备舱的材料结构特点和边界条件,应用FLUENT软件进行了设备舱的数值仿真分析;在此基础上提出了搭建支架的散热方案并对舱内热环境进行了模拟。结果显示,采用搭建支架的措施可使电子设备的表面温度降低5℃,较好地改善了电子设备舱的散热情况。该研究可为航空航天领域电子设备舱的热设计提供参考。

关键词：无人机电子设备舱数值模拟热仿真计算流体力学

维普期刊数据库博看期刊

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双层协同结构改进的高光谱异常检测算法

航空兵器 2024年第4期31卷 121-127页

作者：李欢赵嘉豪刘广涵石锦辉宋江鲁奇周慧鑫西安电子科技大学物理学院西安710071 西安邮电大学西安710071 中国空空导弹研究院河南洛阳471009

在高光谱目标检测领域,基于协同表示的算法展现出优异的性能,但其一直存在异常点对背景字典的污染问题,这一定程度上影响了算法的检测性能。本文提出了一种改进的协同表示高光谱异常检测算法,设计了双层协同表示结构,首先利用第一层协... 详细信息

在高光谱目标检测领域,基于协同表示的算法展现出优异的性能,但其一直存在异常点对背景字典的污染问题,这一定程度上影响了算法的检测性能。本文提出了一种改进的协同表示高光谱异常检测算法,设计了双层协同表示结构,首先利用第一层协同表示算法将大部分异常点检出,并用其邻域进行背景纯化,剔除已检出的异常点对背景字典的污染,然后用纯化的背景字典来预测背景,进而在第二层采用协同表示进行异常检测。仿真试验表明,通过简单的双层协同表示结构可以有效地减轻异常点对背景污染的问题。该算法的检测性能相对基础的协同表示算法有显著的提升,与现有的算法对比,具有相对较好的检测效果。

关键词：高光谱异常检测目标检测背景污染协同表示双层结构

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频率可调谐的双偏振非对称传输器件

哈尔滨工程大学学报 2024年第2期45卷 415-422页

作者：吕婷婷刘东明付天舒史金辉东北石油大学物理与电子工程学院黑龙江大庆163318 哈尔滨工程大学纤维集成光学教育部重点实验室黑龙江哈尔滨150001 哈尔滨工程大学物理与光电工程学院黑龙江哈尔滨150001

为了研究太赫兹超构材料的可调谐非对称传输特性,本文基于相变原理提出一种类S型的双层结构,采用有限积分算法求解其偏振传输特性。利用温度调控二氧化钒的相变特性,实现了频率可调谐的双偏振非对称传输效应。在宽角度入射范围内,45°... 详细信息

为了研究太赫兹超构材料的可调谐非对称传输特性,本文基于相变原理提出一种类S型的双层结构,采用有限积分算法求解其偏振传输特性。利用温度调控二氧化钒的相变特性,实现了频率可调谐的双偏振非对称传输效应。在宽角度入射范围内,45°线偏振光的非对称传输特性保持着较高的工作效率,倾斜入射角为60°时,效率优于0.4,且绝缘态和金属态下的谐振频率几乎保持不变,谐振频率的可调谐度为16.3%。本文所提出的频率可调谐双偏振非对称传输器件在偏振调控、太赫兹通信和太赫兹芯片领域具有潜在的应用前景。

关键词：超构材料非对称传输相变原理二氧化钒偏振调控宽角度频率可调谐太赫兹

Size and elemental composition of dry-deposited particles during a severe dust storm at a coastal site of Eastern China

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Journal of Environmental Sciences 2016年第2期28卷 161-168页

作者： Hongya Niu Daizhou Zhang Wei Hu jinhui shi Ruipeng Li Huiwang Gao Wei Pian Min Hu State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University Hebei Collaborative Innovation Center of Coal Exploitation Hebei University of Engineering Faculty of Environmental and Symbiotic Sciences Prefectural University of Kumamoto Key Laboratory of Marine Environmental Science and Ecology Ocean University of ChinaMinistry of Education

Dry-deposited particles were collected during the passage of an extremely strong dust storm in March, 2010 at a coastal site in Qingdao（36.15°N, 120.49°E）, a city located in Eastern China. The size, morphology, and elemental composition of the particles were quantified with a scanning electron microscope equipped with an energy dispersive X-ray instrument（SEM–EDX）. The particles appeared in various shapes, and their size mainly varied from 0.4to 10 μm, with the mean diameters of 0.5, 1.5, and 1.0 μm before, during, and after the dust storm, respectively. The critical size of the mineral particles settling on the surface in the current case was about 0.3–0.4 μm before the dust storm and about 0.5–0.7 μm during the dust storm. Particles that appeared in high concentration but were smaller than the critical size deposited onto the surface at a small number flux. The elements Al, Si and Mg were frequently detected in all samples, indicating the dominance of mineral particles. The frequency of Al in particles collected before the dust storm was significantly lower than for those collected during and after the dust storm. The frequencies of Cl and Fe did not show obvious changes, while those of S, K and Ca decreased after the dust arrival. These results indicate that the dust particles deposited onto the surface were less influenced by anthropogenic pollutants in terms of particle number.

关键词： Asian dust Dry deposition Morphology Size distribution Elemental composition

Tunable fiber-tip lens based on thermo-optic effect of amorphous silicon

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Chinese Optics Letters 2020年第3期18卷 17-20页

作者： Ping Li Jing Liu Peng Huang Xingyu Zhang jinhui shi Libo Yuan Chunying Guan Key Laboratory of In-Fiber Integrated Optics of Ministry of Education College of ScienceHarbin Engineering UniversityHarbin 150001China

We theoretically demonstrate a compact all-dielectric metasurface fiber-tip lens composed of sub-wavelength amorphous silicon on the end face of a multimode *** full 2πphase control was realized by varying the widths of resonant *** tunable focal length is achieved by using the thermal-optic effect of amorphous *** focal length increases from 309μm to 407μm when the temperature changes by 300 *** temperature controlled all-fiber integrated lens is compact and with high efficiency and provides an excellent platform of a fiber-tip ***,the proposed fiber lens does not have any structural changes during dynamic tuning,which improves the durability and repeatability of the devices.

关键词： fiber-tip lens tunable focus length all-dielectric metasurface thermal-optic effect

A novel integrated microfluidic chip for on-demand electrostatic droplet charging and sorting

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Bio-Design and Manufacturing 2024年第1期7卷 31-42页

作者： jinhui Yao Chunhua He Jianxin Wang Canfeng Yang Ye Jiang Zhiyong Liu Guanglan Liao Tielin shi State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

On-demand droplet sorting is extensively applied for the efficient manipulation and genome-wide analysis of individual ***,state-of-the-art microfluidic chips for droplet sorting still suffer from low sorting speeds,sample loss,and labor-intensive preparation ***,we demonstrate the development of a novel microfluidic chip that integrates droplet generation,on-demand electrostatic droplet charging,and high-throughput *** charging electrode is a copper wire buried above the nozzle of the microchannel,and the deflecting electrode is the phosphate buffered saline in the microchannel,which greatly simplifies the structure and fabrication process of the ***,this chip is capable of high-frequency droplet generation and sorting,with a frequency of 11.757 kHz in the drop *** chip completes the selective charging process via electrostatic induction during droplet ***-demand charged microdroplets can arbitrarilymove to specific exit channels in a three-dimensional(3D)-deflected electric field,which can be controlled according to user requirements,and the flux of droplet deflection is thereby significantly ***,a lossless modification strategy is presented to improve the accuracy of droplet deflection or harvest rate from 97.49% to 99.38% by monitoring the frequency of droplet generation in real time and feeding it back to the charging *** chip has great potential for quantitative processing and analysis of single cells for elucidating cell-to-cell variations.

关键词： Copper wire Droplet generation Droplet sorting Microfluidic chips On-demand charging

Phytochemistry,biological properties and quality control of Chuanxiong Rhizoma:a review

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Journal of Chinese Pharmaceutical Sciences 2020年第11期29卷 753-779页

作者： jinhui shi Ruiyue Li Siyu Yang Hongmei Zhang School of Pharmacy Shanghai University of Traditional Chinese MedicineShanghai 201203China

Chuanxiong Rhizoma is a widely used Chinese herbal medicine in the past 2000 *** Rhizoma is composed of volatile oils,phthalide lactones,phenolic acids,polysaccharides and other *** date,more than 149 compounds in Chuanxiong Rhizoma have been isolated and identified,and some of them have been reported to possess promising biological properties on cardiovascular and central nervous system disorders besides their anti-cancer and antioxidant *** of inflammatory mediators and apoptotic factors are believed to contribute to its *** methods,such as HPLC,GC and UPLC,are employed for qualitative evaluation of Chuanxiong *** this work,harvest period,growing habitat,processing method and storage,which can affect the quality of Chuanxiong Rhizoma,were also *** quality control methods should be developed to ensure the safety,quality and efficacy use of Chuanxiong ***,we collected and analyzed the literature of Chuanxiong Rhizoma published on CNKI,ScienceDirect,Springer link,Wiley and PubMed in past two decades,and up-to-date information of Chuanxiong Rhizoma was provided in this *** suggested ligustilide,butylidenephthalide and total senkyunolides as the chemical markers to evaluate the quality of Chuanxiong ***,the influences of soil conditions and processing methods on Chuanxiong Rhizoma as future research perspectives should also be further assessed.

关键词： Chuanxiong Rhizoma(CXR) Phytochemistry Biological property Quality control