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能量均衡的围捕任务分配方法 预览
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作者 张子迎 吕骏 +3 位作者 徐东 孟宇龙 冯光升 张朦朦 《国防科技大学学报》 EI CAS CSCD 北大核心 2019年第2期107-114,184共9页
随着水下机器人反围捕策略研究的不断深入,水下机器人围捕变得越来越困难。为此构建一种多层环状伏击围捕模型并设计了基于围捕任务的任务分配方法,使得水下机器人能够充分利用自身的特点更好地完成任务。同时,考虑在围捕过程中随时间推... 随着水下机器人反围捕策略研究的不断深入,水下机器人围捕变得越来越困难。为此构建一种多层环状伏击围捕模型并设计了基于围捕任务的任务分配方法,使得水下机器人能够充分利用自身的特点更好地完成任务。同时,考虑在围捕过程中随时间推移,系统内能量会出现消耗不均的现象,据此提出一种能量均衡方法平衡系统能量的消耗。实验证明所提出的基于多层环状围捕模型的能量均衡策略任务分配方法能有效提高围捕成功率,延长系统寿命。 展开更多
关键词 水下机器人 围捕 多层环状伏击围捕模型 任务分配 能量均衡
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Study of neutron production and moderation for sulfur neutron capture therapy 预览
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作者 Meng Peng Guo-Zhu He +3 位作者 Qi-Wei Zhang Bin Shi Hong-Qing Tang Zu-Ying Zhou 《核技术:英文版》 SCIE CAS CSCD 2019年第1期59-66,共8页
Neutron capture therapy with Sulfur-33, similar to boron neutron capture therapy with Boron-10, is effective in treating some types of tumors including ocular melanoma. The key point in sulfur neutron capture therapy ... Neutron capture therapy with Sulfur-33, similar to boron neutron capture therapy with Boron-10, is effective in treating some types of tumors including ocular melanoma. The key point in sulfur neutron capture therapy is whether the neutron beam flux and the resonance capture cross section of 33S(n;α)30 Si reaction at 13.5 keV can achieve the requirements of radiotherapy. In this research,the authors investigated the production of 13.5 keV neutron production and moderation based on an accelerator neutron source. A lithium glass detector was used to measure the neutron flux produced via near threshold7 Li(p,n)7 Be reaction using the time-of-flight method. Furthermore, the moderation effects of different kinds of materials were investigated using Monte Carlo simulation. 展开更多
关键词 SULFUR NEUTRON CAPTURE THERAPY BORON NEUTRON CAPTURE THERAPY 33S(n α)3 Si resonance reaction 7Li(p n)^7 Be NEUTRON source
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Fe-substituted Ba-hexaaluminate with enhanced oxygen mobility for CO2 capture by chemical looping combustion of methane 预览
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作者 Fei Huang Ming Tian +5 位作者 Yanyan Zhu Xiaodong Wang Aiqin Wang Lin Li Jian Lin Junhu Wang 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第2期50-57,共8页
While Fe-based oxygen carriers(OC) are regarded to be promising for chemical looping combustion(CLC),the decrease of CO2 selectivity during deep reduction process and the severe agglomeration of Fe2O3 often occur afte... While Fe-based oxygen carriers(OC) are regarded to be promising for chemical looping combustion(CLC),the decrease of CO2 selectivity during deep reduction process and the severe agglomeration of Fe2O3 often occur after multiple redox cycles due to the low oxygen mobility.Herein,Fe-substituted Bahexaaluminates(Ba FexAl12– xO19,denoted as BFxA-H,x = 1 and 2) prepared by a modified two-step method exhibited not only higher amount of converted oxygen(Ot) and CH4 conversion(77% and 81% vs.17%and 75%) than those prepared by the traditional co-precipitation method(BFxA-C,x = 1 and 2) but also high CO2 selectivity above 92% during the nearly whole reduction from Fe3+ to Fe2+.Furthermore,the BFxA-H exhibited the excellent recyclability during 50 cycles.The better performance was ascribed to the markedly enhanced oxygen mobility which resulted from dominant occupancy of Fe cations in Al(5) sites(Fe5: 71% and 70% vs.49% and 41%) in mirror planes of hexaaluminate leading to larger amount of lattice oxygen coordinated with Fe5(O–Fe5)(0.45 and 0.85 mmol/g vs.0.31 and 0.50 mmol/g).The improvement of oxygen mobility also favored the preservation of chemical state of Fe cations in hexaaluminate structure in the re-oxidation step,resulting in the excellent recyclability of BFxA-H. 展开更多
关键词 CO2 CAPTURE Chemical LOOPING CH4 conversion Oxygen MOBILITY FE-BASED HEXAALUMINATE
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Eutectic mixture promoted CO2 sorption on MgO-TiO2 composite at elevated temperature
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作者 Vishwanath Hiremath Monica Louise T.Trivino Jeong Gil Seo 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第2期80-88,共9页
The development of carbon dioxide (CO2) sorbents that can operate at elevated temperatures is significant for the advancement of pre-combustion capture technologies. Recently, promoter-based systems composed of alkali... The development of carbon dioxide (CO2) sorbents that can operate at elevated temperatures is significant for the advancement of pre-combustion capture technologies. Recently, promoter-based systems composed of alkali/alkaline earth metal nitrates and/or carbonates have been considered as next-generation solid sorbents due to their improved CO2 uptake and kinetics. However, obtaining stable MgO sorbents against temperature swing regeneration still remained challenging. Herein, we report MgO-TiO2 solid sorbents promoted by eutectic mixture (KNO3 and LiNO3) for elevated temperature CO2 sorption. The developed sorbents show improved CO2 sorption capacity, which may be attributed to the alternative CO2 sorption pathway provided by the ionization of highly dispersed MgO in the eutectic mixture. The MgO-TiO2 framework was also shown to assist in retaining the MgO configuration by constraining its interaction with CO2. Furthermore, it is demonstrated that constructing composite structures is essential to improve the CO2 sorption characteristics, mainly recyclability, at elevated temperatures. The developed promoter integrated sorbents showed exceptionally high CO2 sorption capacity of > 30 wt.% at an elevated temperature (300°C) with pronounced stability under temperature swing operation. 展开更多
关键词 MgO-TiO2 COMPOSITE Elevated temperature CO2 capture EUTECTIC mixture promoter MGO stability
iCatch:a new strategy for capturing large DNA fragments using homing endonucleases
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作者 Jingman Wang Anrui Lu +4 位作者 Jiakun Liu Weiren Huang Jin Wang Zhiming Cai Guoping Zhao 《生物化学与生物物理学报:英文版》 SCIE CAS CSCD 2019年第1期97-103,共7页
Natural genetic materials contain many biosynthetic gene clusters encoding potentially valuable natural products,many of which can be used directly without codon optimization or other manipulations.With the developmen... Natural genetic materials contain many biosynthetic gene clusters encoding potentially valuable natural products,many of which can be used directly without codon optimization or other manipulations.With the development of synthetic biology,several DNA assembly standards have been proposed,conveniently facilitating the reuse of natural materials.Among these standards,the iBrick assembly standard was developed by our laboratory to manipulate large DNA fragments,employing two homing endonucleases.Considering the difficulty of cloning large iBrick parts using conventional endonuclease-mediated restriction and ligation methods,we herein present a new method,known as iCatch,which readily captures biosynthetic gene clusters.As the clusters cloned by iCatch have the prefix and suffix of the iBrick standard,they serve as new iBrick parts and are therefore conducive to further editing and assembly with the iBrick standard.iCatch employs the natural homologous recombination system to flank the region of interest with I-Scel and PI-Pspl recognition sites,after which the genome is digested with I-Scel or PI-Pspl and the fragments are then self-ligated to clone the target DNA fragments.We used this method to successfully capture the actinorhodin biosynthetic cluster from Streptomyces coelicolor and then heterologously expressed this cluster in a thermophilic Streptomyces strain.We propose that iCatch can be used for the cloning of DNA sequences that are dozens of kilobases in length,facilitating the heterologous expression of microbial natural products.Moreover,this cloning methodology can be a complementary tool for the iBrick standard,especially in applications requiring the manipulation of large DNA fragments. 展开更多
关键词 GENOMIC CAPTURE HOMING ENDONUCLEASE BIOLOGICAL part HETEROLOGOUS expression
戏曲艺术的360°全景视频采集与呈现初探 预览
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作者 刘浩洋 《演艺科技》 2019年第5期50-53,共4页
通过全景视频技术对戏曲艺术采集的实验过程,介绍戏曲全景视频化的制作手段,并分析探讨戏曲全景视频化的特点。
关键词 戏曲艺术 全景视频 采集 呈现 视阈范围 视觉语言
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Design of a Non-cooperative Target Capture Mechanism 预览
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作者 WANG Chen NIE Hong +1 位作者 CHEN Jinbao PAN Zhengwei 《南京航空航天大学学报:英文版》 EI CSCD 2019年第1期146-153,共8页
A passive compliant non-cooperative target capture mechanism is designed to maintain the non-cooperative target on-orbit. When the relative position between capture mechanism and satellite is confirmed,a pair of four-... A passive compliant non-cooperative target capture mechanism is designed to maintain the non-cooperative target on-orbit. When the relative position between capture mechanism and satellite is confirmed,a pair of four-bar linkages lock the docking ring,which is used for connecting the satellite and the rocket. The mathematical model of capture mechanism and capture space is built by the Denavit-Hartenberg(D-H)method,and the torque of each joint is analyzed by the Lagrange dynamic equation. Besides,the capture condition and the torque of every joint under different capture conditions are analyzed by simulation in MSC. Adams. The results indicate that the mechanism can capture the non-cooperative target satellite in a wide range. During the process of capture,the passive compliant mechanism at the bottom can increase capture space,thereby reducing the difficulty and enhance stability of the capture. 展开更多
关键词 NON-COOPERATIVE target passive COMPLIANCE CAPTURE MECHANISM KINEMATICS ANALYSIS dynamics ANALYSIS
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pH-Responsive and Buffering Macromolecule Aqueous Absorbent and Mathematic Model-Based Feasibility Evaluation for SO2 Capture 预览
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作者 Wei Feng Wenhao Gu +4 位作者 Lühong Zhang Xiaowei Tantai Bin Jiang Huawei Yang Hongjie Zhang 《天津大学学报:英文版》 EI CAS 2019年第3期226-236,共11页
An organic macromolecule,poly(1-vinylimidazole),with an appropriate polymerization degree was proposed and mixed with water to form a novel aqueous absorbent for SO2 capture.This aqueous solution absorbent has the adv... An organic macromolecule,poly(1-vinylimidazole),with an appropriate polymerization degree was proposed and mixed with water to form a novel aqueous absorbent for SO2 capture.This aqueous solution absorbent has the advantages of simple preparation,good physicochemical properties,environment-friendliness,high ability in deep removal of SO2,and excellent reusability.Moreover,pH-responsive behavior,pH buffering absorption mechanism,and their synergistic effect on absorption performance were revealed.The solubilities of SO2 in the absorbent were measured in detail,and the results demonstrated excellent absorption capacity and recyclability.Then,mathematic models that describe SO2 absorption equilibrium were established,and the corresponding parameters were estimated.More importantly,on the basis of model and experimental data,the absorption and desorption could maintain high efficiency within a wide operating region.In summary,this work provided a low-cost,efficient,and unique absorbent for SO2 capture and verified its technical feasibility in industrial application. 展开更多
关键词 Poly(1-vinylimidazole) PH buffer PH responsibility SO2 CAPTURE Flue gas desulfurization
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Prediction of cost and emission from Indian coal-fired power plants with C02 capture and storage using artificial intelligence techniques
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作者 Naushita SHARMA Udayan SINGH Siba Sankar MAHAPATRA 《能源前沿:英文版》 CSCD 2019年第1期149-162,共14页
Coal-fired power plants are one of the most important targets with respect to reduction of CO2 emissions.The reasons for this are that coal-fired power plants offer localized large point sources(LPS)of CO2 and that th... Coal-fired power plants are one of the most important targets with respect to reduction of CO2 emissions.The reasons for this are that coal-fired power plants offer localized large point sources(LPS)of CO2 and that the Indian power sector con tributes to roughly half of all-India CO2emissions.CO2capture and storage(CCS)can be implemented in these power plants for long-temi decarbonisation of the Indian economy.In this paper,two artificial intelligence(Al)techniques—adaptive network based fuzzy inference system(ANFIS)and multi gene genetic programming(MGGP)are used to model Indian coal-fired power plants with CO2 capture.The data set of 75 power plants take the plant size,the capture type,the load and the CO2 emission as the input and the COE and annual CO2 emissions as the output.It is found that MGGP is more suited to these applications with an R2 value of more than 99%between the predicted and actual values,as against the~96%correlation for the ANFIS approach.MGGP also gives the traditionally expected results in sensitivity analysis,which ANFIS fails to give.Several other parameters in the base plant and CO2 capture unit may be included in similar studies to give a more accurate result.This is because MGGP gives a better perspective toward qualitative data,such as capture type,as compared to ANFIS. 展开更多
关键词 carbon CAPTURE and storage power plants artificial INTELLIGENCE genetic PROGRAMMING NEURO fuzzy
Heat of absorption of CO2 in aqueous N,N-diethylethanolamine+N-methyl-1,3-propanediamine solutions at 313K
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作者 Katarzyna Sobala Hanna Kierzkowska-Pawlak 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第3期628-633,共6页
Differential heat of absorption of CO2 in aqueous solutions of N,N-diethylethanolamine(DEEA)and activated DEEA solutions up to a total concentration of 2 mol·L^-1 was measured as a function of CO2 loading at 313.... Differential heat of absorption of CO2 in aqueous solutions of N,N-diethylethanolamine(DEEA)and activated DEEA solutions up to a total concentration of 2 mol·L^-1 was measured as a function of CO2 loading at 313.15 K using a reaction calorimeter.In order to analyze the performance of N-methyl-1,3-propanediamine(MAPA)as an activator,DEEA blended solutions containing 0.05,0.1 and 0.2 mol·L^-1 MAPA were studied.The heat of CO2 absorption in single DEEA solutions was unaffected by changing the DEEA concentration in the range of(0.5–2)mol·L^-1.On the other hand,increasing the concentration of MAPA in aqueous amine mixtures of(DEEA+MAPA)raised the heat of absorption. 展开更多
关键词 CO2 CAPTURE Differential heat of absorption N N-diethylethanolamine N-methyl-1 3-propanediamine AMINE blends
智能无人水下航行器水下回收对接技术综述 预览
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作者 孙叶义 武皓微 +2 位作者 李晔 姜言清 周子烨 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2019年第1期1-11,共11页
针对目前水面母船回收智能无人水下航行器存在的受环境影响大、隐蔽性差、成本高、自动化程度低等不足,AUV水下自主回收对接日益成为研究热点。水下对接可以完成AUV能源补给、数据下载/上传、设备检修等操作,实现AUV水下不间断隐蔽作业... 针对目前水面母船回收智能无人水下航行器存在的受环境影响大、隐蔽性差、成本高、自动化程度低等不足,AUV水下自主回收对接日益成为研究热点。水下对接可以完成AUV能源补给、数据下载/上传、设备检修等操作,实现AUV水下不间断隐蔽作业,具有重要的应用价值。本文结合AUV水下回收对接的特点,归纳了水下对接的优势和困难,分类总结了水下对接的关键技术,包括导引技术、搭载方式、对接装置形式、安全性分析等。综述了近年来各国在AUV水下对接领域的研究成果,并对未来发展方向进行了展望。 展开更多
关键词 智能无人水下航行器 回收 水下对接 搭载方式 安全性 导引 捕捉 几何约束 协调控制
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System Analysis on Supercritical CO2 Power Cycle with Circulating Fluidized Bed Oxy-Coal Combustion
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作者 SHI Yan ZHONG Wenqi +1 位作者 SHAO Yingjuan XIANG Jun 《热科学学报:英文版》 SCIE EI CAS CSCD 2019年第3期505-518,共14页
Supercritical carbon dioxide(S-CO2) Brayton power cycle is a competitive technology to achieve high efficiency in a variety of applications. However, in coal power applications, the CO2 generated from coal combustion ... Supercritical carbon dioxide(S-CO2) Brayton power cycle is a competitive technology to achieve high efficiency in a variety of applications. However, in coal power applications, the CO2 generated from coal combustion still discharges into the atmosphere causing a series of environment problems. In this work, an 300 MWe S-CO2 power cycle with circulating fluidized bed(CFB) oxy-coal combustion was established including air separation unit(ASU), CFB boiler, recuperator system and carbon dioxide compression and purification unit(CPU). Based on the material and energy conservation, the cycle efficiency of S-CO2(620°C, 25 MPa) Brayton power cycle with CFB oxy-coal combustion is evaluated compared to the oxy-coal combustion steam Rankine cycle and S-CO2 Brayton power cycle with the 31.65 kg/s coal supply. After that, the influence of several factors, e.g., exhaust flue gas temperature, split ratio in recuperator system and the oxygen supply on the cycle efficiency was investigated and analyzed. The results show that the net efficiency of S-CO2 power cycle with CFB oxy-coal combustion(32.67%) is much higher than the steam Rankine cycle utilizing CFB with 17.5 Mpa, 540°C steam(27.3%), and 25 Mpa, 620°C steam(30.15%) under the same exhaust flue gas temperature. In addition, lower exhaust flue gas temperature and higher split ratio are preferred to achieve higher cycle efficiency. Lower oxygen supply can reduce the energy consumption of ASU and CPU, further increasing the system net efficiency. However, the energy losses of ASU and CPU are still very large in oxy-coal combustion and need to be improved in further work. 展开更多
关键词 S-CO2 oxy-coal COMBUSTION CO2 CAPTURE CFB BOILER PROCESS simulation
Luminescent BODIPY-based Porous Organic Polymer for CO2 Adsorption
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作者 LIN Yijun YIN Jiafu +2 位作者 LI Xuechao PAN Chunyue KUANG Guichao 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2019年第2期440-445,共6页
Luminescent porous materials have shown various applications such as electronic devices, gas adsorption, energy materials and photocatalysis. Consequently, we designed and prepared a new type borondipyrromethene(BODIP... Luminescent porous materials have shown various applications such as electronic devices, gas adsorption, energy materials and photocatalysis. Consequently, we designed and prepared a new type borondipyrromethene(BODIPY) based porous organic polymer(POP) by using Sonogashira coupling reaction. This POP-1 exhibits high thermal stability with moderate surface area. In addition, POP-1 is highly emissive in a solid state. Due to enrichment of different kinds of heteroatoms in the skeleton of the porous polymer, POP-1 selectively captures carbon dioxide(CO2) with relative high adsorption selectivity of CO2/N2. 展开更多
关键词 POROUS organic polymer LUMINESCENT boron-dipyrromethene(BODIPY) CO2 ADSORPTION selectively CAPTURE
Neurological functional evaluation based on accurate motions in big animals with traumatic brain injury 预览
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作者 Ji-Peng Jiang Xue-Gang Niu +9 位作者 Chen Dai Ke Ma Hui-You Xu Shi-Xiang Cheng Zhi-Wen Zhang Feng Duan Xu Zhu Yu-Ting Wang Xu-Yi Chen Sai Zhang 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第6期991-996,共6页
An accurate and effective neurological evaluation is indispensable in the treatment and rehabilitation of traumatic brain injury.However,most of the existing evaluation methods in basic research and clinical practice ... An accurate and effective neurological evaluation is indispensable in the treatment and rehabilitation of traumatic brain injury.However,most of the existing evaluation methods in basic research and clinical practice are not objective or intuitive for assessing the neurological function of big animals,and are also difficult to use to qualify the extent of damage and recovery.In the present study,we established a big animal model of traumatic brain injury by impacting the cortical motor region of beagles.At 2 weeks after successful modeling,we detected neurological deficiencies in the animal model using a series of techniques,including three-dimensional motion capture,electromyogram and ground reaction force.These novel technologies may play an increasingly important role in the field of traumatic brain injury diagnosis and rehabilitation in the future.The experimental protocol was approved by the Animal Care and Use Committee of Logistics University of People’s Armed Police Force(approval No.2017-0006.2). 展开更多
关键词 nerve REGENERATION evaluation method NEUROLOGICAL deficiency TRAUMATIC brain injury motion capture ELECTROMYOGRAM ground reaction force neural REGENERATION
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高效捕获阪崎肠杆菌免疫磁珠的制备研究 预览
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作者 姚骅珊 朱志强 《安徽化工》 CAS 2019年第1期55-59,共5页
制备以链霉亲和素———生物素介导偶联的免疫磁珠,通过偶联条件和捕获条件的优化,建立高效、特异富集阪崎肠杆菌的方法。结果表明,按照100μgSA/mg磁珠制备链霉亲和素磁珠,以抗体与磁珠表面链霉亲和素物质的量比为3∶1,37℃偶联30min,... 制备以链霉亲和素———生物素介导偶联的免疫磁珠,通过偶联条件和捕获条件的优化,建立高效、特异富集阪崎肠杆菌的方法。结果表明,按照100μgSA/mg磁珠制备链霉亲和素磁珠,以抗体与磁珠表面链霉亲和素物质的量比为3∶1,37℃偶联30min,可获得抗体结合量为386.6μg/mg免疫磁珠。在1mL体系中添加粒径为80nm的链霉亲和素免疫磁珠0.3mg室温孵育30min,纯培养条件下对阪崎肠杆菌捕获效率在80.5%以上,人工污染样品条件下捕获效率可达61.1%以上,非特异性低于5.0%。该免疫磁珠为富集阪崎肠杆菌提供了一种操作简单、捕获效率高、特异性好的方法,可广泛应用于食品中阪崎肠杆菌的检测。 展开更多
关键词 阪崎肠杆菌 免疫磁珠 捕获 偶联
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说“吸睛”
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作者 王逢鑫 《英语世界》 2019年第1期96-97,共2页
“吸睛”的意思是“吸引眼球”“博人眼球”或“吸引注意力”。“吸睛”或“博人眼球”,常常是通过视觉实现的。英语可以用与eye(眼睛)和gaze(凝视)相关的动词词组to catch the eye、to capture the eye、to grab the eye、to attract t... “吸睛”的意思是“吸引眼球”“博人眼球”或“吸引注意力”。“吸睛”或“博人眼球”,常常是通过视觉实现的。英语可以用与eye(眼睛)和gaze(凝视)相关的动词词组to catch the eye、to capture the eye、to grab the eye、to attract the eye、to attract the gaze及相应的形容词词组eye—catching、eye—capturing、eye—grabbing、eye—attracting、gaze—attracting等表示。 展开更多
关键词 CAPTURE 注意力 眼球 形容词 词组
BOC信号自相关函数边峰消除方法改进和性能分析 预览
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作者 张鹏 张胜男 +3 位作者 王存宝 李孟委 张晓峰 李维刚 《中北大学学报:自然科学版》 CAS 2019年第3期265-268,275共5页
BOC调制信号自相关函数的多峰性会给信号捕获带来模糊影响,而传统自相关边峰消除技术需要计算BOC(n,n)的互相关函数和自相关函数,存在计算量大,软硬件实现复杂的缺点.本文对自相关边峰消除技术加以改进,只需进行自相关函数计算就可以实... BOC调制信号自相关函数的多峰性会给信号捕获带来模糊影响,而传统自相关边峰消除技术需要计算BOC(n,n)的互相关函数和自相关函数,存在计算量大,软硬件实现复杂的缺点.本文对自相关边峰消除技术加以改进,只需进行自相关函数计算就可以实现正余弦BOC北斗信号的捕获.分析和实验结果表明,改进后的算法运算量低,采用所构造的函数捕获伪码相位的主峰和边峰的比值明显高于采用直接捕获伪码相位的主峰和边峰的比值,由1dB提升至12dB更容易准确捕获北斗微弱信号,验证了所构造的函数的有效性. 展开更多
关键词 北斗 自相关函数 ASPECT 捕获
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基于矩阵分解的空间系绳系统不完全反馈控制
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作者 王长青 付立春 +1 位作者 扎波罗特诺夫·尤里 李爱军 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2019年第5期902-911,共10页
针对利用空间系绳系统(STS)进行面内捕获过程中系绳展开后状态保持阶段及捕获完成后系统面内运动抑制等问题,在面内角和面内角速率信号丢失情况下,基于矩阵分解采用不完全状态反馈控制方法,设计出能够抑制系绳展开完成后所出现的非标称... 针对利用空间系绳系统(STS)进行面内捕获过程中系绳展开后状态保持阶段及捕获完成后系统面内运动抑制等问题,在面内角和面内角速率信号丢失情况下,基于矩阵分解采用不完全状态反馈控制方法,设计出能够抑制系绳展开完成后所出现的非标称行为、捕获后面内摆动的张力控制律,进而使系统回稳。将所设计的控制律与线性二次调节器(LQR)+降维观测器方法对比,在参数不确定的条件下检验该控制律的控制效果。仿真结果表明,所设计的控制律在超调量和调节时间上优于LQR+降维观测器方法,能够有效控制系绳的展开误差及捕获过程所带来的面内扰动。所设计的控制律结构简单,控制效果良好,且设计过程无需参数调整。 展开更多
关键词 空间系绳系统(STS) 捕获 矩阵分解 不完全反馈 稳定
基于云平台的教学活动视频数据采集传输系统 预览
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作者 成也 李乐桐 范玥 《仪器仪表用户》 2019年第3期6-8,共3页
本文基于阿里云OSS存储的SDK,研究基于云平台的视频文件自动传输软件,可以通过配置传输时间、传输参数、传输文件切分规则,实现本地录制视频自动传输至云平台,让用户可以不受时间和地点限制,随时随地获取历史课堂视频,方便进行课堂状态... 本文基于阿里云OSS存储的SDK,研究基于云平台的视频文件自动传输软件,可以通过配置传输时间、传输参数、传输文件切分规则,实现本地录制视频自动传输至云平台,让用户可以不受时间和地点限制,随时随地获取历史课堂视频,方便进行课堂状态分析。 展开更多
关键词 云平台 教学视频数据 采集 传输
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双浮体波浪能装置的振荡和能量转换特性研究 预览
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作者 张亮 金鹏 +2 位作者 周斌珍 政雄波 刘恒序 《船舶与海洋工程学报:英文版》 CSCD 2019年第1期54-63,共10页
In this study, we investigated the hydrodynamic and energy conversion performance of a double-float wave energy converter(WEC) based on the linear theory of water waves. The generator power take-off(PTO) system is mod... In this study, we investigated the hydrodynamic and energy conversion performance of a double-float wave energy converter(WEC) based on the linear theory of water waves. The generator power take-off(PTO) system is modeled as a combination of a linear viscous damping and a linear spring. Using the frequency domain method, the optimal damping coefficient of the generator PTO system is derived to achieve the optimal conversion efficiency(capture width ratio).Based on the potential flow theory and the higher-order boundary element method(HOBEM), we constructed a threedimensional model of double-float WEC to study its hydrodynamic performance and response in the time domain. Only the heave motion of the two-body system is considered and a virtual function is introduced to decouple the motions of the floats. The energy conversion character of the double-float WEC is also evaluated. The investigation is carried out over a wide range of incident wave frequency. By analyzing the effects of the incident wave frequency, we derive the PTO’s damping coefficient for the double-float WEC’s capture width ratio and the relationships between the capture width ratio and the natural frequencies of the lower and upper floats. In addition, it is capable to modify the natural frequencies of the two floats by changing the stiffness coefficients of the PTO and mooring systems. We found that the natural frequencies of the device can directly influence the peak frequency of the capture width, which may provide an important reference for the design of WECs. 展开更多
关键词 Double-float WEC Energy CONVERSION CAPTURE WIDTH ratio Optimal DAMPING RESONANCE
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