检索结果-南通市图书馆

Searching for γ-ray emission from LOTAAS pulsars

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2021年第3期21卷 61-68页

作者： Qi-Wei Lu Zhong-Xiang Wang yi xing Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of the Chinese Academy of Sciences Beijing 100049China Department of Astronomy Yunnan UniversityKunming 650091China

The LOw-Frequency ARray(LOFAR)has recently conducted a survey(LOFAR Tied-Array Allsky Survey;LOTAAS)for pulsars in the Northern hemisphere that resulted in discoveries of 73 new *** the purpose of studying the properties of these pulsars,we search for theirγ-ray counterparts using the all-sky survey data obtained with the Large Area Telescope(LAT)onboard the Fermi Gamma-Ray Space Telescope(Fermi).We analyze the LAT data for 70 LOTAAS pulsars(excluding two millisecond pulsars and one with the longest known spin period of 23.5 s).We find one candidate counterpart to PSR J1017+30,which should be searched for theγ-ray pulsation signal once its timing solution is *** other LOTAAS pulsars,we derive their 0.3-500 GeV flux upper *** order to compare the LOTAAS pulsars with the knownγ-ray pulsars,we also derive the 0.3-500 GeVγ-ray fluxes for 112 of the latter contained in the Fermi LAT fourth source *** on the properties of theγ-ray pulsars,we derive upper limits on the spin-down luminosities of the LOTAAS *** upper limits are not very constraining but help suggest that most of the LOTAAS pulsars probably have<10^(33) erg s^(-1) spin-down luminosities and are not expected to be detectable with Fermi LAT.

关键词： stars:pulsars stars:neutron gamma rays:stars

The Compensation of Speed Ripple Caused by the Angle-Measuring Error of Inductosyn Using Neural Network

在线全文

学校读者我要写书评

暂无评论

The Compensation of Speed Ripple Caused by the Angle-Measuri...

Hybrid deep neural network based prediction method for unsteady flows with moving boundary

2001 International Conferences on Info-tech and Info-net

作者： yi Guo-xing Ma Guang-Cheng Wang Chang-Hong Inertial Testing Technology and Equipment Research Center Harbin Institute of Technology

ISBN: (纸本)0780370104;9780780370104

＜正＞This paper tackles the problem of the compensation of speed ripple of brushless DC motor by neural *** speed ripple is caused by the error of inductosyn angle-measurement. This error is equal to add a disturbance to the input of the speed control system.A parallel three-layer feedforward artificial neural network（FANN） has been proposed to compensation this error in order to improve the speed performance of the DC *** compensation is based on the separating technique of the angle-measuring error of *** online learning algorithm for the FANN has also been *** practical result illustrate that the speed performance of the motor will be greatly improved by the proposed compensation.

关键词： Feedforward Artificial Neural Network(FANN) Iductosyn Angle Measurement Ripple of speed

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2021年第10期37卷 1557-1566,I0003页

作者： Ren-Kun Han Zhong Zhang yi-xing Wang Zi-Yang Liu Yang Zhang Gang Chen State Key Laboratory for Strength and Vibration of Mechanical Structures Shannxi Key Laboratory for Environment and Control of Flight VehicleSchool of Aerospace EngineeringXi’an Jiaotong UniversityXi’an710049China Science and Technology on Reliability and Environment Engineering Laboratory Beijing Institute of Structure and Environment EngineeringBeijing100076China

Any motion, forced or free, of boundary affects the flow field around this boundary. A new kind of reduced order model (ROM) based on hybrid deep neural network is proposed to model flow field evolution process of unsteady flow around moving boundary. This hybrid deep neural network can map the relationship between the flow field at the next time step and the flow field and boundary positions at the previous time steps. Based on the learned information, the hybrid deep neural network can quickly and accurately predict the flow field. Unsteady flows around forced oscillation cylinder with various amplitudes, frequencies, and Reynolds numbers are simulated to establish the training and testing datasets. The prediction results of the hybrid deep neural network and the computational fluid dynamics (CFD) simulation results are consistent with high accuracy. The forces on the moving boundary can be integrated through the predicted flow field data. Good performance makes this new ROM method can be used in many fluid dynamics research fields, which needs fast and accurate simulation.

关键词： Deep neural network Flow fields prediction Moving boundary

Genetic diversity and temporal dynamics of phytoplankton viruses in East Lake, China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Virologica Sinica 2015年第4期30卷 290-300页

作者： Mei-Niang Wang xing-yi Ge Yong-Quan Wu xing-Lou Yang Bing Tan Yu-Ji Zhang Zheng-Li Shi Key Laboratory of Special Pathogens and Biosafety Wuhan Institute of Virology Chinese Academy of Sciences

Phytoplankton viruses are important components of aquatic ecosystems. However, their prevalence and genetic diversity in marine and freshwater systems are largely under estimated owing to the immense size of water bodies and limitations in virus discovery techniques. In this study, we conducted a 1-year survey of phytoplankton virus communities by collecting surface water monthly from an inland lake(East Lake) in China between May 2012 and April 2013. We examined four phytoplankton viruses, i.e., myoviruses, podoviruses, siphoviruses, and phycodnaviruses, and seven sets of primers were used to target conserved genes within these four species. In this year-long investigation, a total of 358 different virus-related sequences from four virus families were obtained. All virus families were detected in all months, except for cyanopodoviruses, which were only identified during eight of the 12 months surveyed. Moreover, virus abundance and diversity changed dynamically over time. Phylogenetic analysis revealed that the majority of viral sequences from East Lake, China displayed distinct clustering patterns compared with published sequences. These results supported the existence of a highly diverse and unique phytoplankton virus community in East Lake, China.

关键词： cyanophage phycodnavirus genetic diversity dynamic

Total laparoscopic segmental gastrectomy for gastrointestinal stromal tumors: A case report

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2020年第15期8卷 3365-3371页

作者： yi-xing Ren Ming He Peng-Cheng Ye Shou-Jiang Wei Department of General Surgery and Institute of Hepato-Biliary-Pancreas and Intestinal Disease Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina

BACKGROUND Gastrointestinal stromal tumors are lesions that originate from digestive tract *** laparoscopic techniques,including local resections,wedge resections and partial gastrectomies,have been used ***,there are no reports on laparoscopic segmental gastrectomy for gastrointestinal stromal *** SUMMARY We present our analysis of 17 patients who were admitted to our hospital from January 2014 to December *** tumors were located in the corpus and antrum of the stomach,close to the lesser curvature of the *** tumors originated from the anterior wall in nine cases and from the posterior wall of the stomach in eight *** segmental gastrectomy and end-to-end anastomosis between the proximal and the distal residual stomach were used in all *** mean operative time was 112.4 *** mean length of hospital stay was 4.6 *** operative blood loss was 73.5 *** were no leaks,no postoperative bleeding nor need for *** postoperative follow-up was 35.4 *** Visick grading index showed fewer gastrointestinal symptoms 3 mo after *** patients(11.8%)had reflux esophagitis and *** Laparoscopic segmental gastrectomy may be a new function-preserving gastrectomy that is feasible for treatment of gastrointestinal stromal tumors that grow in the middle third of the stomach and on the lesser stomach curvature.

关键词： Gastrointestinal stromal tumors Laparoscopy Segmental gastrectomy Digestive tract Case report

RF front-end for digital beam position monitor signal processor

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2011年第2期22卷 65-69页

作者： yi xing LENG Yongbin LAI Longwei ZHANG Ning YANG Guisen Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China Graduate School of the Chinese Academy of Sciences Beijng 100049 China

RF circuit board has a significant impact on performance of the Digital Beam Position Monitor (DBPM) in storage ring of a synchrotron radiation *** this paper,a front-end RF board is designed for DBPM,and schematics of the RF board and the test results are *** view of the inevitable inconsistency in the multi-channel circuit,a calibration circuit is designed to reduce such an *** test results show that the calibration method is useful for beam current dependence which is sensitive to channels inconsistency.

关键词：位置检测数字波束信号处理器射频前端电路板设计 DBPM 同步辐射

Touschek lifetime study based on the precise bunch-by-bunch BCM system at SSRF

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2019年第9期30卷 126-133页

作者： Fang-Zhou Chen Zhi-Chu Chen yi-Mei Zhou Ning Zhang Bo Gao xing-yi Xu Yong-Bin Leng Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049 China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201200 China

Continuous tracking of bunch charges is the key to maintain stable operations in a storage ring in top-up mode. Recently, a precise bunch-by-bunch beam-current measurement (BCM) system has been developed at the Shanghai Synchrotron Radiation Facility. To avoid the influence of longitudinal oscillation on the amplitudes of the sampling points, a method called two-point equilibrium sampling is introduced. The results, obtained during routine operation time, show that the relative resolution of the measurement of the bunch charges is better than 0.02%. With this high resolution, the new BCM system is able to monitor the bunch-by-bunch beam lifetime. By using the filling pattern information, the Touschek lifetime and the vacuum lifetime can also be calculated. In this paper, the principle of the new method and the experiments is presented in detail.

关键词： Beam-current measurement Bunch-bybunch Touschek lifetime Vacuum lifetime SSRF

广东鹅源多杀性巴氏杆菌的分离鉴定、耐药表型和耐药基因的检测及相关性分析

在线全文

学校读者我要写书评

暂无评论

中国预防兽医学报 2024年第2期46卷 121-127页

作者：苏文楠杨智灿张美琳钟嘉诚陈亦杏陈济铛张溢珊张济培佛山科学技术学院广东佛山528225 佛山天牧生物科技有限公司广东佛山528225

为了解广东地区鹅源多杀性巴氏杆菌(Pm)的流行情况、药物敏感性、耐药基因的携带情况以及耐药表型与耐药基因的相关性,本实验对2019年~2022年从广东地区采集的193份疑似感染Pm病鹅的心脏血液和肝脏组织划线接种于不同的培养基分离细菌,... 详细信息

为了解广东地区鹅源多杀性巴氏杆菌(Pm)的流行情况、药物敏感性、耐药基因的携带情况以及耐药表型与耐药基因的相关性,本实验对2019年~2022年从广东地区采集的193份疑似感染Pm病鹅的心脏血液和肝脏组织划线接种于不同的培养基分离细菌,对分离菌纯化后采用PCR扩增分离菌的KMT1基因并测序,采用多重PCR扩增分离菌的5个荚膜基因及8个脂多糖基因,分析分离菌的荚膜分型与脂多糖(LPS)分型。结果显示分离到83株鹅源Pm,其中82株为荚膜A型,1株无法通过荚膜定型;LPS分型为L1型。采用K-B纸片扩散法检测分离菌的药物敏感性;通过PCR检测分离菌7类药物的15种耐药基因,包括β-内酰胺类(bla_(CTX-M)、bla_(TEM)、bla_(OXA))、氨基糖苷类(aadA1、aph(3’)Ila)、喹诺酮类(qnrA、qnrB、qnrS)、酰胺醇类(floR)、四环素类(tetM、tetX)、大环内酯类(ermF、ereD)、磺胺类(sul1、sul3)耐药基因。采用统计学软件SPSS22中的完全随机设计两样本率的卡方检验分析分离菌的耐药表型和相应耐药基因的相关性。药敏试验结果显示,83株鹅源Pm对多种药物敏感性较高,其中对喹诺酮类的环丙沙星和氧氟沙星、氨基糖苷类的丁胺卡那和大观霉素、β-内酰胺类的头孢曲松、磺胺类的复方新诺明、大环内酯类的阿奇霉素敏感的菌株占比均在63%以上;对氨基糖苷类的链霉素和卡那霉素耐药的菌株占比高于50%,对氨基糖苷类的新霉素和四环素类的四环素耐药的菌株分别占49.40%(41/83)和46.99%(39/83)。耐药基因的检测结果显示,分离菌检出耐药基因qnrB、sul3、blaTEM、aadA1、aph(3’)Ila、ereD、ermF、tetM、floR,检出率分别为9.63%(8/94)、27.71%(23/83)、28.92%(24/83)、48.19%(40/83)、14.46%(12/83)、49.40%(41/83)、3.61%(3/83)、1.20%(1/83)、32.53%(27/83),未检出耐药基因qnrA、qnrS、sul1、tetX、bla_(CTX-M)、bla_(OXA)。相关性分析结果显示,aadA1基因与Pm对新霉素、链霉素、卡那霉素、大观霉素的耐药性具有极显著的相关性(P<0.001);bla_(CTX-M)基因、floR基因分别与Pm对头孢拉定、氟苯尼考的耐药性具有显著相关性(P<0.05)。上述结果表明,广东地区鹅源Pm主要为A∶L1基因型,对多种药物敏感,耐药基因携带率不高,部分药物的耐药表型与耐药基因具有相关性。本研究为广东地区鹅源Pm病的监测和防治提供参考依据,为Pm耐药机制的研究奠定基础。

关键词：多杀性巴氏杆菌药物敏感性试验耐药基因

Gold-leaching performance and mechanism of sodium dicyanamide

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2021年第11期28卷 1759-1768页

作者： Gen-zhuang Li Jue Kou yi xing Yang Hu Wei Han Zi-yuan Liu Chun-bao Sun University of Science and Technology Beijing School of Civil and Resource EngineeringBeijing 100083China University of Science and Technology Beijing School of Energy and Environmental EngineeringBeijing 100083China

In this work,sodium dicyanamide(SD)was used as a leaching reagent for gold recovery,and the effects of the SD dosage and solution pH on the gold-leaching performance were investigated.A gold recovery of 34.8%was obtained when SD was used as the sole leaching reagent at a dosage of 15 kg/*** the presence of a certain amount of potassium ferrocyanide(PF)in the SD solution,the gold recovery was found to increase from 34.8%to 57.08%.Using the quartz crystal microbalance with dissipation(QCM-D)technique,the leaching kinetics of SD with and without PF were *** QCM-D results indicate that the gold-leaching rate increased from 4.03 to 39.99 ng·cm^(–2)·min^(–1) when the SD concentration was increased from 0 to 0.17 mol/L,and increased from 39.99 to 272.62 ng·cm^(–2)·min^(–1) when 0.1 mol/L of PF was used in combination with *** pregnant solution in the leaching tests was characterized by X-ray photoelectron spectroscopy and electrospray mass spectrometry,which indicated that Au and(N(CN)2)–in the SD solution formed a series of metal complex ions,[AuNax(N(CN)2)x+2]–(x=1,2,3,or 4).

关键词： gold leaching sodium dicyanamide QCM-D leaching kinetics potassium ferrocyanide