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多端交通视频分析任务卸载决策

控制与决策 2024年第8期39卷 2773-2782页

作者：温震宇胡慧峰钱滨洪榛俞立浙江工业大学网络空间安全研究院杭州310023 浙江工业大学信息工程学院杭州310023 纽卡斯尔大学计算机学院纽卡斯尔NE45TG

针对智慧交通中多点位监控视频分析时出现的计算任务繁重、设备之间资源利用不均衡的问题,提出一种基于云控制的视频分析卸载方案.首先,针对客户端算力不足而无法完成视频分析任务的问题,使用一种视频卸载框架,将部分视频分析任务切块... 详细信息

针对智慧交通中多点位监控视频分析时出现的计算任务繁重、设备之间资源利用不均衡的问题,提出一种基于云控制的视频分析卸载方案.首先,针对客户端算力不足而无法完成视频分析任务的问题,使用一种视频卸载框架,将部分视频分析任务切块卸载至云服务器处理;其次,针对服务器与多客户端之间的算力资源竞争问题,提出一种阶段优化卸载算法,平衡设备之间负荷,提高资源利用率;最后,针对不同点位的客户端需求不同的问题,在算法中加入精度和能耗偏好,满足不同客户端的需求.与其他卸载方案对比的实验表明,所提出方案能够更好地对视频分析任务进行合理分配,提高系统收益,并通过扩展实验验证所提出系统的扩展能力.

关键词：多端视频分析任务卸载资源竞争卸载决策智慧交通

RXTE /ASM and Swift /BAT observations of spectral transitions in bright X-ray binaries in 2005-2010

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Research in Astronomy and Astrophysics 2011年第4期11卷 434-444页

作者： Jing Tang wen-Fei yu zhen Yan Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Shanghai 200030 China

We have studied X-ray spectral state transitions that can be seen in the long- term monitoring light curves of bright X-ray binaries from the All-Sky Monitor （ASM） onboard the Rossi X-ray Timing Explorer （RXTE） and the Burst Alert Telescope （BAT） onboard Swift during a period of five years from 2005 to 2010. We have applied a program to automatically identify the hard-to-soft （H-S） spectral state transitions in the bright X-ray binaries monitored by the ASM and the BAT. In total, we identified 128 hard-to-soft transitions, of which 59 occurred after 2008. We also determined the transition fluxes and the peak fluxes of the following soft states, updated the measurements of the luminosity corresponding to the H-S transition and the peak luminosity of the following soft state in about 30 bright persistent and transient black hole and neutron star binaries following yu ＆Yan, and found the luminosity correlation and the luminosity range of spectral transitions in data between 2008-2010 are about the same as those derived from data before 2008. This further strengthens the idea that the luminosity at which the H-S spectral transition occurs in the Galactic X-ray binaries is determined by non-stationary accretion parameters such as the rate-of-change of the mass accretion rate rather than the mass accretion rate itself. The correlation is also found to hold in data of individual sources 4U 1608-52 and 4U 1636-53.

关键词： X-rays binaries -- stars neutron -- black hole physics

Recurrence after spontaneous separation of epiretinal membrane in a young woman:a case report

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International Journal of Ophthalmology(English edition) 2023年第3期16卷 476-478页

作者： Qiao-Zhu Zeng wen-zhen yu Department of Ophthalmology Eye Diseases and Optometry InstitutePeking University People’s HospitalBeijing100044China Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases College of OptometryPeking University Health Science CenterBeijing 100044China

Dear Editor,We report a case of recurrence after spontaneous separation of epiretinal membrane (ERM) in a young woman with suspected retinal *** is defined as the fibrocellular membrane that proliferates on the inner surface of neurosensory retina at the macular *** ERM(iERM) usually occurs without a clearly identifiable cause in patients of more than 50 years of age and a great discrepancy in its prevalence from 1.02%to 28.9%among different ethnic groups were noted in previous epidemiologic studies^([1-3]).

关键词： separation epi young

Artificial Neural Network Modeling of Microstructure During C-Mn and HSLA Plate Rolling

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Journal of Iron and Steel Research International 2009年第2期16卷 80-83页

作者： TAN wen LIU zhen-yu WU Di WANG Guo-dong The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

An artificial neural network （ANN） model for predicting transformed mierostrueture in conventional rolling process and therrnomechanical controlled process （TMCP） is proposed. The model uses austenite grain size and retained strain, which can be calculated by using microstructure evolution models, together with a measured cooling rate and chemical compositions as inputs and the ferrite grain size and ferrite fraction as outputs. The predicted re- suits show that the model can predict the transformed microstructure which is in good agreement with the measured one, and it is better than the empirical equations. Also, the effect of the alloying elements on transformed products has been analyzed by using the model. The tendency is the same as that in the reported articles. The model can be used further for the optimization of processing parameters, mierostructure and properties in TMCP.

关键词： artificial neural network TMCP microstructure ferrite grain size

The Effect of Vineyard Cover Crop on Main Monomeric Phenols of Grape Berry and Wine in Vitis viniferal L. cv. Cabernet Sauvignon

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Agricultural Sciences in China 2010年第3期9卷 440-448页

作者： XI Zhu-mei ZHANG zhen-wen CHENG yu-feng LI Hua College of Enology Northwest A＆F University/Shaanxi Engineering Research Center for Viti-Viniculture Yangling 712100 P.R.China

This study was conducted to determine the effect of cover crop inter-row in vineyard on main mono-phenol content of grape berry and wine. Three such cover crops, two perennial legumes （white clover and alfalfa） and a perennial gramineous grass （tall fescue） were sown in vineyard. The main phenolic compounds of mature grape berry and wines vinified under the same conditions were extracted with ethyl acetate and diethyl ether and analyzed by high- performance liquid chromatography （HPLC） by comparing to soil tillage. A total of ten phenolic compounds were identified and quantified in the different grape berry and wines, including nonflavonoids （hydroxybenzoic and hydroxycinnamic acids） and flavonoids （flavanols and flavonols）. The concentration of flavonoid compounds （409.43 to 538.63 mg kg^-1 and 56.16 to 81.30 mg L^-1） was higher than nonflavonoids （76.91 to 98.85 mg kg^-1 and 30.65 to 41.22 mg L^-1） for Cabernet Sauvignon grape and wine under different treatments, respectively. In the flavonoid phenolics, Catechin was the most abundant in the different grapes and wines, accounting for 74.94 to 79.70% and 48.60 to 50.62% of total nonanthocyanin phenolics quantified, respectively. Compared to soil tillage, the sward treatments showed a higher content of main mono-phenol and total nonanthocyanin phenolics in grapes and wines. There were significant differences between two cover crop treatments （tall fescue and white clover） and soil tillage for the content of benzoic acid, salicylic acid, caffeic acid, catechin, and total phenolics in the grape berry （P 〈 0.05 or P〈0.01）. The wine from tall fescue cover crop had the highest gallic acid, caffeic acid and catechin. Cover crop system increased the total nonanthocyanin phenolics of grapes and wines in order of the four treatments： tall fescue, white clover, alfalfa, and soil tillage （control）. Cover crop in vineyard increased total phenols of grape berry and wine, and thus improved the quality of wine evidently.

关键词： vineyard cover crops inter-row Cabernet Sauvignon grape berry wine monomeric phenols

Placental growth factor expression is reversed by anti-vascular endothelial growth factor therapy under hypoxic conditions

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World Journal of Pediatrics 2014年第3期10卷 262-270页

作者： Ai-Yi Zhou yu-Jing Bai Min Zhao wen-zhen yu Lv-zhen Huang Xiao-Xin Li Department of Ophthalmology the Second Affi liated Hospital of Medical College of Xi'an Jiaotong UniversityXi'an 710004Shaanxi ProvinceChina Key Laboratory of Vision Loss and Restoration Ministry of EducationDepartment of OphthalmologyPeople's HospitalPeking UniversityBeijingChina

Background:Clinical trials have revealed that the antivascular endothelial growth factor(VEGF)therapies are effective in retinopathy of prematurity(ROP).But the low level of VEGF was necessary as a survival signal in healthy conditions,and endogenous placental growth factor(PIGF)is redundant for *** purpose of this study was to elucidate the PIGF expression under hypoxia as well as the infl uence of anti-VEGF therapy on ***:CoCl2-induced hypoxic human umbilical vein endothelial cells(HUVECs)were used for an in vitro study,and oxygen-induced retinopathy(OIR)mice models were used for an in vivo *** expression patterns of PIGF under hypoxic conditions and the infl uence of anti-VEGF therapy on PIGF were evaluated by quantitative reverse transcription-polymerase chain reaction(RTPCR).The retinal avascular areas and neovascularization(NV)areas of anti-VEGF,anti-PIGF and combination treatments were *** PIGF concentration was evaluated by ELISA after *** vasoactive effects of exogenous PIGF on HUVECs were investigated by proliferation and migration ***:PIGF mRNA expression was reduced by hypoxia in OIR mice,in HUVECs under hypoxia and anti-VEGF ***,PIGF expression was reversed by anti-VEGF therapy in the OIR model and in HUVECs under *** PIGF significantly inhibited HUVECs proliferation and migration under normal conditions,but it stimulated cell proliferation and migration under ***-PIGF treatment was effective for neovascular tufts in OIR mice(P<0.05).Conclusion:The finding that PIGF expression is iatrogenically up-regulated by anti-VEGF therapy provides a consideration to combine it with anti-PIGF therapy.

关键词： human umbilical vein endothelial cells oxygen-induced retinopathy placental growth factor vascular endothelial growth factor

Inhibition of corneal neovascularization by topical application of nintedanib in rabbit models

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International Journal of Ophthalmology(English edition) 2021年第11期14卷 1666-1673页

作者： Juan Chen Xue Ding Wei Du Xin Tang wen-zhen yu Department of Ophthalmology Peking University People's HospitalEye Diseases and Optometry InstituteBeijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid DiseasesCollege of OptometryPeking University Health Science CenterBeijing 100044China Department of Ophthalmology Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 402218China

AIM:To evaluate the potential efficacy and mechanisms of nintedanib in corneal neovascularization(NV)in rabbit ***:Corneal NV was induced using 1 mol/L Na ***(n=21)were randomized to 3 groups:Group 1 were treated with 0.9%NaCl,Group 2 with Avastin(5 mg/mL),and Group 3 with nintedanib(1 mg/mL).All treatments star ted 1 d af ter alkaline burns and were topically performed 3 times a day for 2 *** were taken on a slit lamp microscope on day 7 and *** NV area,the length of the vascularization and angiogenesis index(AI)were used to evaluate the corneal *** day 14,the immunohistochemical(IHC)studies of the cornea were *** blot was performed to test the expression levels of vascular endothelial growth factor(VEGF),Akt,p-Akt,P38,p-P38,MMP-2 and ***:The corneal NV area,vessel length and AI in Group 3 were significantly lower than Group 2,with both being lower than Group *** staining showed that VEGF was significantly overexpressed in the epithelium and stroma of cornea following alkaline *** contrast,the level of VEGF was significantly suppressed in both Group 2 and Group *** blot results further confirmed that,compared with Group 1,Group 3 had significantly reduced expressions of VEGF,Akt,p-Akt,p-P38,MMP-2,and MMP-9 in corneal *** of lower levels of MMP-2,AKT,and p-AKT in Group 3 than Group 2 were ***:Nintedanib and Avastin can effectively inhibit corneal NV,with P38 MAPK and AKT signaling pathways being possibly *** seems more effective than Avastin and has the potential to be a novel therapy for preventing corneal NV.

关键词： corneal neovascularization nintedanib vascular endothelial growth factor animal model

Conceptual design of a 714-MHz RFQ for compact proton injectors and development of a new tuning algorithm on its aluminium prototype

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Nuclear Science and Techniques 2024年第1期35卷 45-58页

作者： Yi-Xing Lu wen-Cheng Fang yu-Sen Guo zhen-Tang Zhao Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800China University of Chinese Academy of Sciences Beijing 101408China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201204China Shanghai Key Laboratory of Cryogenics&Superconducting RF Technology Shanghai 201800China ShanghaiTech University Shanghai 201210China

Radio frequency quadrupoles(RFQs),which are crucial components of proton injectors,significantly affect the performance of proton accelerator *** RFQ with a high frequency of 714 MHz dedicated to compact proton injectors for medi-cal applications is designed in this *** RFQ is designed to accelerate proton beams from 50 keV to 4 MeV within a short length of 2 m and can be matched closely with the downstream drift tube linac to capture more particles through a preliminary *** develop an advanced RFQ,challenging techniques,including fabrication and tuning method,must be evaluated and verified using a *** aluminium prototype is derived from the conceptual design of the RFQ and then redesigned to confirm the radio frequency performance,fabrication procedure,and feasibility of the tuning ***,a new tuning algorithm based on the response matrix and least-squares method is developed,which yields favorable results based on the prototype,i.e.,the errors of the dipole and quadrupole components reduced to a low level after several tuning *** from the conceptual design and techniques obtained from the prototype,the formal mechanical design of the 2-m RFQ is ready for the next manufacturing step.

关键词： Compact proton injector RFQ IH-DTL High gradient Tuning

Enhanced red luminescence of Ca_(3)Si_(2−x)M_(x)O_(7):Eu^(3+)(M=Al,P)phosphors via partial substitution of Si^(4+) for applications in white light-emitting diodes

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Rare Metals 2024年第2期43卷 736-748页

作者： yu-Hao Ma Xi Gao wen-Tao Zhang zhen-Rui Yang Zhou Zhao Chen Qu College of Materials and Chemistry and Chemical Engineering Chengdu University of TechnologyChengdu610059China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China International Advanced Energy Science Research and Education Center Graduate School of Energy ScienceKyoto UniversityYoshida-HonmachiKyoto606-8501Japan

A red-emitting phosphor Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) with partial Al^(3+)/P^(5+) substitution on Si^(4+) was synthesized via a simple solid-state method,and the effects of the introduction of the M^(3+/5+)(M=Al,P)ions on the crystal structure and photoluminescence performance of Ca_(2.91)Si_(2−x)M_(x)O_(7):0.09Eu^(3+) phosphors were *** X-ray diffraction(XRD),energy-dispersive X-ray spectroscopy(EDS),and X-ray photoelectron spectroscopy(XPS)results revealed that the structure of Ca_(3)Si_(2)O_(7) remained the same after the introduction of Al^(3+) and P^(5+) *** characteristic emission of Eu^(3+)-doped Ca_(3)Si_(2−x)M_(x)O_(7) phosphors exhibited two main peaks at 617 nm(red)and 593 nm(orange)under excitation at 394 nm,which originated from the^(5)D_(0)→^(7)F_(2)and^(5)D_(0)→^(7)F_(1) electron transitions of Eu^(3+) *** the partial substitution of Al^(3+) and P^(5+),the red emission intensities of the Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) phosphors were significantly enhanced by 1.88-and 1.42-fold,respectively,which is attributed to the crystal-field effect around Eu^(3+).Meanwhile,the luminescence intensities of the Ca_(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+) and Ca_(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) phosphors at 210℃ were 79.36%and 77.53%of those at 30°C,respectively,indicating their excellent thermal ***,the as-prepared Ca_(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+)and Ca_(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) red-emitting phosphors were combined with a near-ultraviolet chip of 395 nm to fabricate red-light-emitting diode(LED)and white(w)-LED devices with excellent chromaticity *** summary,Al^(3+)/P^(5+)-substituted Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) can serve as red-emitting phosphors for applications in w-LEDs.

关键词： Ca_(3)Si_(2)O_(7) Red-emitting phosphor Structure substitution Luminescence enhancement Crystal-field effect White light-emitting diode