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The environmental analysis and site selection of mussel and large yellow croaker aquaculture areas based on high resolution remote sensing
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作者 Lina Cai Jie Yin +3 位作者 Xiaojun Yan Yongdong Zhou Rong Tang Menghan Yu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期66-86,共21页
Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was propose... Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was proposed and applied to determine the basic environmental characteristics of the best mussel and large yellow croaker aquaculture areas.This methodology includes the first step of extraction of the location distribution and the second step of the extraction of internal environmental factors.The fishery ranching index(FRI1,FRI2)was established to extract the mussel and the large yellow croaker aquaculture area in Zhoushan,using Gaofen-1(GF-1)and Gaofen-6(GF-6)satellite data with a special resolution of 2 m.In the second step,the environmental factors such as sea surface temperature(SST),chlorophyll a(Chl-a)concentration,current and tide,suspended sediment concentration(SSC)in mussel aquaculture area and large yellow croaker aquaculture area were extracted and analyzed in detail.The results show the following three points.(1)For the extraction of the mussel aquaculture area,FRI1 and FRI2 are complementary,and the combination of FRI1 and FRI2 is suitable to extract the mussel aquaculture area.As for the large yellow croaker aquaculture area extraction,FRI2 is suitable.(2)Mussel aquaculture and the large yellow croaker aquaculture area in Zhoushan are mainly located on the side near the islands that are away from the eastern open waters.The water environment factor template suitable for mussel and large yellow croaker aquaculture was determined.(3)This two-step remote sensing method can be used for the preliminary screening of potential site selection for the mussels and large yellow croaker aquaculture area in the future.the fishery ranching index(FRI1,FRI2)in this paper can be applied to extract the mussel and large yellow croaker aquaculture areas in coastal waters around the world. 展开更多
关键词 mussel aquaculture area large yellow croaker aquaculture area high resolution satellite site selection environmental analysis
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Highly sensitive digital optical sensor with large measurement range based on the dual-microring resonator with waveguide-coupled feedback 被引量:3
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作者 向星烨 王葵如 +3 位作者 苑金辉 晋博源 桑新柱 余重秀 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期284-288,共5页
We propose a novel high-performance digital optical sensor based on the Mach-Zehnder interferential effect and the dual-microring resonators with the waveguide-coupled feedback. The simulation results show that the se... We propose a novel high-performance digital optical sensor based on the Mach-Zehnder interferential effect and the dual-microring resonators with the waveguide-coupled feedback. The simulation results show that the sensitivity of the sensor can be orders of magnitude higher than that of aconventional sensor, and high quality factor is not critical in it. Moreover, by optimizing the length of the feedback waveguide to be equal to the perimeter of the ring, the measurement range of the proposed sensor is twice as much as that of the conventional sensor in the weak coupling case. 展开更多
关键词 optical sensor microring resonator high sensitivity large measurement range
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Measures for controlling large deformations of underground caverns under high in-situ stress condition--A case study of JinpingⅠhydropower station 被引量:10
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作者 Shengwu Song Xuemin Feng +3 位作者 Chenggang Liao Dewen Cai Zhongxu Liu Yunhao Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2016年第5期605-618,共14页
The Jinping I hydropower station is a huge water conservancy project consisting of the highest concrete arch dam to date in the world and a highly complex and large underground powerhouse cavern. It is located on the ... The Jinping I hydropower station is a huge water conservancy project consisting of the highest concrete arch dam to date in the world and a highly complex and large underground powerhouse cavern. It is located on the right bank with extremely high in-situ stress and a few discontinuities observed in surrounding rock masses. The problems of rock mass deformation and failure result in considerable challenges related to project design and construction and have raised a wide range of concerns in the fields of rock mechanics and engineering. During the excavation of underground caverns, high in-situ stress and relatively low rock mass strength in combination with large excavation dimensions lead to large deformation of the surrounding rock mass and support. Existing experiences in excavation and support cannot deal with the large deformation of rock mass effectively, and further studies are needed. In this paper, the geological conditions, layout of caverns, and design of excavation and support are first introduced, and then detailed analyses of deformation and failure characteristics of rocks are presented. Based on this, the mechanisms of deformation and failure are discussed, and the support adjustments for controlling rock large deformation and subsequent excavation procedures are proposed. Finally, the effectiveness of support and excavation adjustments to maintain the stability of the rock mass is verified. The measures for controlling the large deformation of surrounding rocks enrich the practical experiences related to the design and construction of large underground openings, and the construction of caverns in the Jinping I hydropower station provides a good case study of large-scale excavation in highly stressed ground with complex geological structures, as well as a reference case for research on rock mechanics. 展开更多
关键词 large-scale underground caverns high in-situ stress large deformationDeformation controlling technologies Jinping I hydropower station
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Dataset of Large Gathering Images for Person Identification and Tracking
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作者 Adnan Nadeem Amir Mehmood +7 位作者 Kashif Rizwan Muhammad Ashraf Nauman Qadeer Ali Alzahrani Qammer H.Abbasi Fazal Noor Majed Alhaisoni Nadeem Mahmood 《Computers, Materials & Continua》 SCIE EI 2023年第3期6065-6080,共16页
This paper presents a large gathering dataset of images extracted from publicly filmed videos by 24 cameras installed on the premises of Masjid Al-Nabvi,Madinah,Saudi Arabia.This dataset consists of raw and processed ... This paper presents a large gathering dataset of images extracted from publicly filmed videos by 24 cameras installed on the premises of Masjid Al-Nabvi,Madinah,Saudi Arabia.This dataset consists of raw and processed images reflecting a highly challenging and unconstraint environment.The methodology for building the dataset consists of four core phases;that include acquisition of videos,extraction of frames,localization of face regions,and cropping and resizing of detected face regions.The raw images in the dataset consist of a total of 4613 frames obtained fromvideo sequences.The processed images in the dataset consist of the face regions of 250 persons extracted from raw data images to ensure the authenticity of the presented data.The dataset further consists of 8 images corresponding to each of the 250 subjects(persons)for a total of 2000 images.It portrays a highly unconstrained and challenging environment with human faces of varying sizes and pixel quality(resolution).Since the face regions in video sequences are severely degraded due to various unavoidable factors,it can be used as a benchmark to test and evaluate face detection and recognition algorithms for research purposes.We have also gathered and displayed records of the presence of subjects who appear in presented frames;in a temporal context.This can also be used as a temporal benchmark for tracking,finding persons,activity monitoring,and crowd counting in large crowd scenarios. 展开更多
关键词 large crowd gatherings a dataset of large crowd images highly uncontrolled environment tracking missing persons face recognition activity monitoring
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Two highly efficient accumulation models of large gas fields in China 被引量:2
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作者 Wang Hongjun Bian Congsheng +2 位作者 Liu Guangdi Sun Mingliang Li Yongxin 《Petroleum Science》 SCIE CAS CSCD 2014年第1期28-38,共11页
Based on reserve abundance,large gas fields in China can be divided into two types:type one of high abundance large gas fields,dominated by structural gas reservoirs; type two of low abundance large gas fields,domina... Based on reserve abundance,large gas fields in China can be divided into two types:type one of high abundance large gas fields,dominated by structural gas reservoirs; type two of low abundance large gas fields,dominated by stratigraphic and lithologic gas reservoirs.The formation of these two types of large gas fields is related to the highly efficient accumulation of natural gas.The accumulation of high abundance gas fields is dependent on the rapid maturation of the source kitchen and huge residual pressure difference between the gas source kitchen and reservoir,which is the strong driving force for natural gas migration to traps.Whereas the accumulation of low abundance gas fields is more complicated,involving both volume flow charge during the burial stage and diffusion flow charge during the uplift stage,which results in large area accumulation and preservation of natural gas in low porosity and low permeability reservoirs.This conclusion should assist gas exploration in different geological settings. 展开更多
关键词 Natural gas gas source kitchen highly efficient accumulation large gas field reserve abundance resource potential
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Development of a large nanocrystalline soft magnetic alloy core with highμ'_(p)Qf products for CSNS-Ⅱ 被引量:2
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作者 Bin Wu Xiao Li +5 位作者 Zhun Li Chun-Lin Zhang Yang Liu Wei Long Xiang Li Jian Wu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第8期45-54,共10页
A waterproof nanocrystalline soft magnetic alloy core with a size of O.D.850 mm×I.D.316 mm×H.25 mm for radio frequency acceleration was successfully developed by winding 18μm 1k107b MA ribbons.Theμ'_(p... A waterproof nanocrystalline soft magnetic alloy core with a size of O.D.850 mm×I.D.316 mm×H.25 mm for radio frequency acceleration was successfully developed by winding 18μm 1k107b MA ribbons.Theμ'_(p)Qf products reached 7.5,10,and 12 GHz at 1,3,and 5 MHz,respectively.Theμ'_(p)Qf products of the MA core(O.D.250 mm×I.D.100 mm×H.25 mm)manufactured using a 13μm MA ribbon further increased by 30%.Detailed improvements on the MA core manufacture process are discussed herein.Continuous high-power tests on the new MA cores demonstrated its good performance of waterproofness,particularly its stability of highμ'_(p)Qf products.The MA core with highμ'pQf product and large size can operate under a high average RF power,high electric field,and in deionized water,which will be used in the China Spallation Neutron Source PhaseⅡ(CSNS-Ⅱ). 展开更多
关键词 large size magnetic alloy core high insulation and low stress coating Waterproof structure Transverse magnetic field annealing high power MA-loaded cavity
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High-dose Chemotherapy Combined with Autologous Hematopoietic Stem Cell Transplantation as Frontline Therapy for Intermediate/High-risk Diffuse Large B Cell Lymphoma 被引量:2
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作者 Qin WEN Li GAO +11 位作者 Jing-kang XIONG Qiong LI San-bin WANG Ji-shi WANG Fang LIU Cheng ZHANG Yao LIU Pei-yan KONG Xian-gui PENG Jun RAO Lei GAO Xi ZHANG 《Current Medical Science》 SCIE CAS 2021年第3期465-473,共9页
The role of autologous hematopoietic stem cell transplantation(auto-HSCT)following high-dose chemotherapy has been validated and accepted as a standard treatment for patients with relapsed diffuse large B-cell lymphom... The role of autologous hematopoietic stem cell transplantation(auto-HSCT)following high-dose chemotherapy has been validated and accepted as a standard treatment for patients with relapsed diffuse large B-cell lymphoma(DLBCL).However,its clinical efficacy as frontline therapy remains to be elucidated.This study aimed to examine the feasibility of frontline auto-HSCT for newly diagnosed intermediate/high-risk DLBCL patients.We retrospectively reviewed the data of 223 patients treated with frontline auto-HSCT or chemotherapy alone(year 2008-2014)from four hospitals.The median follow-up time was 29.4 months.Between the two treatment arms among the intermediate/high-risk DLBCL patients,the 3-year overall survival(OS)and progression-free survival(PFS)rates of patients given frontline auto-HSCT were 87.6%and 81.9%,respectively,and the chemotherapy-alone group showed 3-year OS and PFS rates of 64.9%and 59.59%,respectively.Compared with the chemotherapy-alone group,the frontline auto-HSCT could eliminate the adverse impact of non-germinal center B-cell(GCB)type.In addition,in the frontline auto-HSCT group,patients who achieved complete response(CR)at auto-HSCT had a longer survival time than those who did not achieve CR.Our results suggested that frontline auto-HSCT could improve the prognosis of intennediate/high-risk DLBCL patients. 展开更多
关键词 diffuse large B-cell lymphoma intermediate/high risk autologous hematopoietic stem cell transplantation frontline therapy
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A Highly Compact Third-Order Silicon Elliptical Micro-Ring Add-Drop Filter with a Large Free Spectral Range 被引量:1
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作者 关欢 李智勇 +2 位作者 沈海华 王睿 俞育德 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第3期61-63,共3页
We demonstrate a highly compact third-order elliptical micro-ring add-drop filter based on a silicon-on-insulator wafer. The elliptical micro-ring resonator has a major radius of 6μm (minor radius of 4.112μm) and ... We demonstrate a highly compact third-order elliptical micro-ring add-drop filter based on a silicon-on-insulator wafer. The elliptical micro-ring resonator has a major radius of 6μm (minor radius of 4.112μm) and a large free spectral range of 18 nm. Experimental results show a box-like channel dropping response, which has a 3 dB bandwidth of -2.7nm, high out-of-band signal rejection of around 40dB and a very low drop loss (〈0.5dB). Simulation agrees well with the experiments. The footprint of the whole chip is only 0.0003mm2. 展开更多
关键词 FSR A highly Compact Third-Order Silicon Elliptical Micro-Ring Add-Drop Filter with a large Free Spectral Range
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Spheroidization process in large-deformed high-carbon steel 被引量:2
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作者 LIAN Fuliang LIU Yongning 《Baosteel Technical Research》 CAS 2014年第1期24-28,共5页
In this study,the spheroidization process of large-deformed steel under various conditions was researched.Steel with a high carbon content (1.0% C) was first treated thermomechanically using multipass rolling.Then ... In this study,the spheroidization process of large-deformed steel under various conditions was researched.Steel with a high carbon content (1.0% C) was first treated thermomechanically using multipass rolling.Then it underwent spheroidization treatments at different heating temperatures,using various heating times and cooling rates.Spheroidization processes with a lower heating temperature,shorter heating time,or faster cooling rate than those of the traditional process all showed good results,indicating that the spheroidization process was promoted significantly by the large deformation process.Grain refinement and fragmentation of cementite,along with the large deformation process,promoted this spheroidization process. 展开更多
关键词 large-deformed SPHEROIDIZATION high-carbon steel
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Large deformation and failure mechanism analyses of Tangba high slope with a high-intensity and complex excavation process 被引量:2
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作者 HOU Qi-dong WU Gao-jian +2 位作者 LI Hai-bo FAN Gang ZHOU Jia-wen 《Journal of Mountain Science》 SCIE CSCD 2019年第2期453-469,共17页
The Tangba high slope is mainly composed of coarse soils and supplies core wall materials for the construction of the Changheba dam. Since the filling intensity of the Changheba dam is high, the Tangba high slope suff... The Tangba high slope is mainly composed of coarse soils and supplies core wall materials for the construction of the Changheba dam. Since the filling intensity of the Changheba dam is high, the Tangba high slope suffers from a high-intensity excavation process, and reinforcement measures are usually not implemented immediately. Moreover, the distribution of useful materials is uneven and insufficient, and the mixing of different soil materials is necessary; thus, multiple simultaneous excavations and secondary excavation are inevitable. In the construction period from 2012 to 2016, large deformations occurred in this area, and one of the largest monitored horizontal deformations whose direction points to the opposite side of the valley even reached more than 8000 mm. According to field investigation, site monitoring and theoretical analysis, the large deformation in the Tangba high slope can be divided into two phases. In the first phase, the excavation construction breaks the original stress equilibrium state; in the second phase, the precipitation infiltration accelerates the deformation. Thus, the excavation construction and precipitation infiltration are the two major factors promoting the deformation, and the high-intensity and complex excavation process is the fundamental cause. Notably, rate of slope deformation significantly accelerated in rainy seasons due to precipitation infiltration; the rate also accelerated in early 2016 due to the high-intensity, complex excavation process. Comprehensively considering the above factors, timely and effective reinforcement measures are essential. 展开更多
关键词 Coarse soil SLOPE large deformation high-intensity and COMPLEX EXCAVATION Failure mechanism Reinforcement measures
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Large aperture phase-coded diffractive lens for achromatic and 16°field-of-view imaging with high efficiency
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作者 马顾 郑鹏磊 +4 位作者 胡正文 马锁冬 许峰 浦东林 王钦华 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第7期349-360,共12页
Diffractive lenses(DLs)can realize high-resolution imaging with light weight and compact size.Conventional DLs suffer large chromatic and off-axis aberrations,which significantly limits their practical applications.Al... Diffractive lenses(DLs)can realize high-resolution imaging with light weight and compact size.Conventional DLs suffer large chromatic and off-axis aberrations,which significantly limits their practical applications.Although many achromatic methods have been proposed,most of them are used for designing small aperture DLs,which have low diffraction efficiencies.In the designing of diffractive achromatic lenses,increasing the aperture and improving the diffraction efficiency have become two of the most important design issues.Here,a novel phase-coded diffractive lens(PCDL)for achromatic imaging with a large aperture and high efficiency is proposed and demonstrated experimentally,and it also possesses wide field-of-view(FOV)imaging at the same time.The phase distribution of the conventional phase-type diffractive lens(DL)is coded with a cubic function to expand both the working bandwidth and the FOV of conventional DL.The proposed phase-type DL is fabricated by using the laser direct writing of grey-scale patterns for a PCDL of a diameter of 10 mm,a focal length of 100 mm,and a cubic phase coding parameter of 30π.Experimental results show that the working bandwidth and the FOV of the PCDL respectively reach 50 nm and 16°with over 8%focusing efficiency,which are in significant contrast to the counterparts of conventional DL and in good agreement with the theoretical predictions.This work provides a novel way for implementing the achromatic,wide FOV,and high-efficiency imaging with large aperture DL. 展开更多
关键词 achromatic imaging diffractive lens phase coding large aperture high efficiency
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Synthesis of Macro-Mesostructured γ-Al_2O_3 with Large Pore Volume and High Surface Area by a Facile Secondary Reforming Method 被引量:2
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作者 Meng Xiuhong Duan Linhai +2 位作者 Xie Xiaohua Wang Qiang Wang Haiyan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2014年第2期20-28,共9页
Through improving the aging process during synthesis of the support, γ-Al2O3 with large pore volume and high surface area was synthesized by a facile secondary reforming method. The synthesis parameters, such as the ... Through improving the aging process during synthesis of the support, γ-Al2O3 with large pore volume and high surface area was synthesized by a facile secondary reforming method. The synthesis parameters, such as the reaction temperature, the first aging temperature and the second aging temperature, were investigated. The textural properties of γ-Al2O3 were characterized by means of N2 adsorption-desorption isotherms, X-ray powder diffractometry(XRD), scanning electron microscopy(SEM), Fourier transform infrared(FTIR) spectroscopy and thermogravimetry(TG). The experimental results indicated that AACH and amorphous AlOOH were the precursors of alumina, which were formed via precipitation from solutions after reaction of aluminum sulphate with ammonium hydrogen carbonate. The precursor nanocrystallites grew and re-assembled during the secondary reforming process, which resulted in an increased pore size and pore volume and a decreased bulk density. The as-synthesized γ-Al2O3 materials featured meso/macroporosity, large pore volume(2.175 cm3/g), high surface area(237.8 m2/g), and low bulk density(0.284 g/mL). 展开更多
关键词 高表面积 氧化铝 合成 转化方法 介观结构 傅里叶变换红外光谱 X射线粉末衍射 扫描电子显微镜
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Adaptive Antenna-Activation Based Beamforming for Large-Scale MIMO Communication Systems of High Speed Railway 被引量:3
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作者 Meng Cheng Shaoshi Yang Xuming Fang 《China Communications》 SCIE CSCD 2016年第9期12-23,共12页
Large-scale array aided beamforming improves the spectral efficiency(SE) as a benefit of high angular resolution.When dual-beam downlink beamforming is applied to the train moving towards cell edge,the inter-beam ambi... Large-scale array aided beamforming improves the spectral efficiency(SE) as a benefit of high angular resolution.When dual-beam downlink beamforming is applied to the train moving towards cell edge,the inter-beam ambiguity(IBA) increases as the directional difference between beams becomes smaller.An adaptive antenna activation based beamforming scheme was proposed to mitigate IBA.In the district near the base station(BS),all antenna elements(AEs) were activated to generate two beams.As the distance from the train to the BS increased,only the minimum number of AEs satisfying the resolution criterion would be activated.At the cell edge,one beam was switched off due to intolerable IBA.The proposed scheme can achieve SE gain to the non-adaptive scheme and show more robustness against the direction-of-arrival(DOA) estimation error. 展开更多
关键词 自适应天线 波束形成 激活 高速铁路 通信系统 MIMO 角分辨率 高频谱效率
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Key Techniques of High-voltage and Large-capacity Series Hybrid Active Power Filters 被引量:10
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作者 LIU Jianben CHEN Qiaofu +1 位作者 DAI Shaojun HE Guanjin 《中国电机工程学报》 EI CSCD 北大核心 2013年第12期I0001-I0022,179,共22页
基于基波磁通补偿的串联混合型有源电力滤波器(active power filter,APF)应用于高电压、大容量的谐波抑制场合时,受变压器励磁支路谐波电压的影响,逆变器不能等效为基波电流源,其输出电流将含有大量的谐波,从而影响滤波效果。以逆变... 基于基波磁通补偿的串联混合型有源电力滤波器(active power filter,APF)应用于高电压、大容量的谐波抑制场合时,受变压器励磁支路谐波电压的影响,逆变器不能等效为基波电流源,其输出电流将含有大量的谐波,从而影响滤波效果。以逆变器为核心,推导出在励磁支路谐波压降影响下的串联变压器的谐波等效阻抗。并以此为基础,从理论上分析励磁电感和变比对串联变压器谐波等效阻抗和APF滤波效果的影响。仿真结果验证了理论分析的正确性。最后,针对广东某厂10kV、1MVA电力负荷,研制一套基于基波磁通补偿的串联混合型有源滤波器工程样机,取得非常好的滤波效果。 展开更多
关键词 混合型有源电力滤波器 高电压 大容量 技术 脉冲宽度调制 等效阻抗 过滤效果 磁通补偿
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Cold Atom Cloud with High Optical Depth Measured with Large Duty Cycle
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作者 张骏 顾振杰 +2 位作者 钱鹏 韩枝光 陈洁菲 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期96-99,共4页
We present a cold atom system with a dark-line two-dimensional magneto-optical trap, to increase the atomic density by suppressing the atomic radiation pressure. Optical depth (OD) and duty cycle are used to evaluat... We present a cold atom system with a dark-line two-dimensional magneto-optical trap, to increase the atomic density by suppressing the atomic radiation pressure. Optical depth (OD) and duty cycle are used to evaluate the system performance. We demonstrate a 100% increase in OD with the dark line, and obtain an ultrahigh OD of 264 with 10% for the duty cycle. Also, with an efficient dark line region, the OD could maintain above i00 with duty cycle as high as 30%. The cold atomic ensemble with an ultrahigh OD with a 10%-30% duty cycle is particularly advantageous in quantum i^formation processing and communication. 展开更多
关键词 Cold Atom Cloud with high Optical Depth Measured with large Duty Cycle MOT OD
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Highly Integrated Multiplexing and Buffering Electronics for Large Aperture Ultrasonic Arrays
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作者 Robert Wodnicki Haochen Kang +9 位作者 Di Li Douglas N.Stephens Hayong Jung Yizhe Sun Ruimin Chen Lai-Ming Jiang Nestor E.Cabrera-Munoz Josquin Foiret Qifa Zhou Katherine W.Ferrara 《Biomedical Engineering Frontiers》 2022年第1期262-283,共22页
Large aperture ultrasonic arrays can be implemented by tiling together multiple pretested modules of high-density acoustic arrays with closely integrated multiplexing and buffering electronics to form a larger apertur... Large aperture ultrasonic arrays can be implemented by tiling together multiple pretested modules of high-density acoustic arrays with closely integrated multiplexing and buffering electronics to form a larger aperture with high yield.These modular arrays can be used to implement large 1.75D array apertures capable of focusing in elevation for uniform slice thickness along the axial direction which can improve image contrast.An important goal for large array tiling is obtaining high yield and sensitivity while reducing extraneous image artifacts.We have been developing tileable acoustic-electric modules for the implementation of large array apertures utilizing Application Specific Integrated Circuits(ASICs)implemented using 0.35μm high voltage(50 V)CMOS.Multiple generations of ASICs have been designed and tested.The ASICs were integrated with high-density transducer arrays for acoustic testing and imaging.The modules were further interfaced to a Verasonics Vantage imaging system and were used to image industry standard ultrasound phantoms.The first-generation modules comprise ASICs with both multiplexing and buffering electronics on-chip and have demonstrated a switching artifact which was visible in the images.A second-generation ASIC design incorporates low switching injection circuits which effectively mitigate the artifacts observed with the first-generation devices.Here,we present the architecture of the two ASIC designs and module types as well imaging results that demonstrate reduction in switching artifacts for the second-generation devices. 展开更多
关键词 highLY large utilizing
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A Novel Soft Start Method of Super Large Capacity High Voltage Motor
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作者 Jiaxin Yuan Chuansheng Wang +1 位作者 Yong Zhu Baichao Chen 《CES Transactions on Electrical Machines and Systems》 CSCD 2019年第3期302-308,共7页
The large current generated by starting directly of super large capacity and high voltage induction motor would have a huge impact on the grid as well as the motor itself.The variation of the power factor and electrom... The large current generated by starting directly of super large capacity and high voltage induction motor would have a huge impact on the grid as well as the motor itself.The variation of the power factor and electromagnetic torque during direct start of motors with different capacity and voltage levels are obtained.Aiming at the problem that the secondary impact of auto-transformer starter is too large and the cost of magnetic control starter is too high,the auto-transformer and magnetic control soft start method of super large capacity and high voltage motor is proposed and the basic working principle is analyzed.The calculation formula of cost for magnetic control soft starter and auto-transformer and magnetic control soft starter is deduced,and specific examples are analyzed and compared.It is concluded that the choice of auto-transformer with appropriate tapping ratio can greatly reduce the cost of auto-transformer and magnetic control soft starter compared with the other one.Finally,the simulation and experiment results show that the start method can effectively avoid secondary current impact and constrain the motor starting current to less than 2.5 times the rated current. 展开更多
关键词 Auto-transformer buck magnetic controllable reactor super large capacity high voltage induction motor soft start.
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THE ANALYSIS OF RESCURED HIGH TENSION PNEUMOTHORAX AND LARGE AREA CHEST WALL DEFECTS
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作者 Guoxian ZhaoSurgical Dept. Of Anshun City People’s Hospital, Guizhou Province, 561000 P.R. of China 《慢性病学杂志》 2005年第A07期626-628,共3页
After analyzing 15 clinical case, 2 of which is especially representative, about perforating injury at the areaintegrates thoracic and abdominal cavities in our hospital from Jan. 1988 to Aug. 2001, the writers have s... After analyzing 15 clinical case, 2 of which is especially representative, about perforating injury at the areaintegrates thoracic and abdominal cavities in our hospital from Jan. 1988 to Aug. 2001, the writers have summarized some therapyon it. First, to avoid delaying surgery operation , those who are injured at that area seriously should be treated with surgeryoperations immediately without X ray and supersonic checks. Second, the positive check results of suspect patients should behelpful for diagnosis, however the negative ones also could not be excluded of the diagnosis clues. The writers think that theconcomitant observation results with the development of illness are most significant. Third, the emphasis of treatments for thoseinjuries should be paid on abdomen. Explore the abdomen is necessary for the situations that abdominal substantial organs bleedand vacuum organs break, thoracic close drainage is sufficient for treating most thoracic trauma cases. It has been improved to beconvenient to check the thoracic cavities by cutting off the diaphragma temporarily if necessary. Fourth, as it was reported that asmany as 97 per cent of patients will have visceral injury dues to abdominal gunshot wound, all gunshot wounds be done with anexploratory laparotomy without hesitation. Fifth, resuscitating of patients as soon as possible is the key to decrease the mortalityand complications. Sixth, acute pancreas injury should be treated as acute pancreatitis. 展开更多
关键词 high TENSION PNEUMOTHORAX large AREA CHEST WALL DE
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Comparing High-resistance Grounding Method with Resonance Grounding Method for Large Generators
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作者 Yao Huannian Cao Meiyue(Xiamen Electric Power Administration) 《Electricity》 1997年第3期22-25,共4页
For large generators, the problem of high-resistance grounding method and the advantages of resonance, grounding method are discussed in detail, and an overall comparison is given in this paper. It is recommended that... For large generators, the problem of high-resistance grounding method and the advantages of resonance, grounding method are discussed in detail, and an overall comparison is given in this paper. It is recommended that the latter should be adopted so as to increase the operation reliability of large generators and power systems. 展开更多
关键词 high Comparing high-resistance Grounding Method with Resonance Grounding Method for large Generators
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Alterations and Its Mechanisms of Wnt Signal Pathway in Human High-matastatatic Large Cell Lung Cancer Cell Line L9981 by Transfecting with Nm23-H1 Gene 被引量:1
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作者 Junke FU Zhe WANG +7 位作者 Sen WEI Gang CHEN Zhigang LI Jun CHEN Hongyu LIU Zhihao WU Ke XU Qinghua ZHOU 《中国肺癌杂志》 CAS 2009年第6期477-479,共3页
Backgroud and Objective Tumor metastasis is not only the malignant marker and characteristics of lung cancer, but also the main cause of failure to cure and lose their life of the
关键词 肺癌 扩散 临床 化疗
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