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Estimation of radio Luminosity of Pulsars and Study of Their Evolution~*

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Science China Mathematics 1993年第4期36卷 468-476页

作者：吴鑫基 r.n.manchester Department of Geophysics Peking University Beijing 100871 PRC Division of radiophysics CSIRO P.O. Box 76 Epping N.S. W. 2121 Australia

The intensity distribution of emission beam and the new radio luminosity formula of pulsars are presented on the basis of the geometrical relations of polar-cap model. There are 102 pulsars with the new radio luminosity values. It is shown that the radio luminosity can be described only by one relation L∞(B/p^2)^(1.1) or L∞Q'^(-1.4) over the whole range of period and period derivatives, which is contrary to other recently suggested luminosity laws.

关键词： pulsars luminosity evolution

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脉冲星射电光度的估计及其演化规律的研究

中国科学（A辑） 1992年第8期23卷 859-866页

作者：吴鑫基 r.n.manchester 天文和天体物理中心CCAST(World 澳大利亚CSIrO射电物理研究所

本文从极冠模型出发导出辐射束的强度分布和新的光度公式.新的光度公式无需对磁倾角和视线扫过辐射束的部位作出假定,采用新的射电光度值来研究光度的演化规律,发现在周期和周期变率的整个取值范围内射电光度可以用关系式L∝(B/P^2)^(1... 详细信息

本文从极冠模型出发导出辐射束的强度分布和新的光度公式.新的光度公式无需对磁倾角和视线扫过辐射束的部位作出假定,采用新的射电光度值来研究光度的演化规律,发现在周期和周期变率的整个取值范围内射电光度可以用关系式L∝(B/P^2)^(1.1)和L∝Q’^(-1.4)来描写.这和近几年流行的光度规律不同.

关键词：脉冲星射电光度演化

四颗南天脉冲星在1560 MHz上的偏振观测

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天体物理学报 1991年第3期11卷 227-233页

作者：吴鑫基 r.n.manchester A.G.Lyne 天文和天体物理中心CCAST(World Laboratory) Division of radiophysics. CSIrO. Australia nrAL.University of manchester. Jodrell Bank. U. K.

本文给出88年6月和7月期间在澳大利亚Parkes进行的一次南天脉冲星偏振观测的部分有意义的结果。频率为1560MHz。采用了Jodrell Bank天文台新研制成的2×16×5MHz滤波系统,使这次观测具有很强的消色散能力和较高的灵敏度。这4颗南天脉冲... 详细信息

本文给出88年6月和7月期间在澳大利亚Parkes进行的一次南天脉冲星偏振观测的部分有意义的结果。频率为1560MHz。采用了Jodrell Bank天文台新研制成的2×16×5MHz滤波系统,使这次观测具有很强的消色散能力和较高的灵敏度。这4颗南天脉冲星具有较强的线偏振,为首次获得的高频偏振资料。

关键词：脉冲星偏振观测

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Parkes脉冲星数据库使用方法(英文)

天文研究与技术 2012年第3期9卷 229-236页

作者： J.Khoo G.Hobbs r.n.manchester D.Miller J.Dempsey CSIrO Astronomy and Space Science Australia Telescope National FacilityP.O.Box 76EppingNSW 1710Australia CSIrO Information Management & Technology(IM&T) PO Box 225Dickson ACT 2602Australia

Parkes脉冲星数据库目前已经收集了从1991年至今由Parkes望远镜观测的165755个数据文件。数据文件及其存取方法遵循虚拟天文台协议。介绍了脉冲星数据库的使用方法,以及使用在线界面进行数据获取的例子。

关键词：脉冲星天文数据库多样性

A machine learning driven 3D+1D model for efficient characterization of proton exchange membrane fuel cells

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Energy and AI 2024年第3期17卷 281-294页

作者： Yuwei Pan Haijun ruan Billy Wu Yagya n.regmi Huizhi Wang nigel P.Brandon Department of Earth Science and Engineering Imperial College LondonLondon SW72AZUK Dyson School of Design Engineering Imperial College LondonLondon SW72AZUK Centre for E-Mobility and Clean Growth Coventry UniversityCoventry CV15FBUK manchester Fuel Cell Innovation Centre Department of Natural SciencesManchester Metropolitan UniversityManchester M15GDUK Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK

The computational demands of 3D continuum models for proton exchange membrane fuel cells remain substantial. One prevalent approach is the hierarchical model combining a 2D/3D flow field with a 1D sub-model for the catalyst layers and membrane. However, existing studies often simplify the 1D domain to a linearized 0D lumped model, potentially resulting in significant errors at high loads. In this study, we present a computationally efficient neural network driven 3D+1D model for proton exchange membrane fuel cells. The 3D sub-model captures transport in the gas channels and gas diffusion layers and is coupled with a 1D electrochemical sub-model for microporous layers, membrane, and catalyst layers. To reduce computational intensity of the full 1D description, a neural network surrogates the 1D electrochemical sub-model for coupling with the 3D domain. Trained by model-generated large synthetic datasets, the neural network achieves root mean square errors of less than 0.2%. The model is validated against experimental results under various relative humidities. It is then employed to investigate the nonlinear distribution of internal states under different operating conditions. With the neural network operating at 0.5% of the computing cost of the 1D sub-model, the hybrid model preserves a detailed and nonlinear representation of the internal fuel cell states while maintaining computational costs comparable to conventional 3D+0D models. The presented hybrid data-driven and physical modeling framework offers high accuracy and computing speed across a broad spectrum of operating conditions, potentially aiding the rapid optimization of both the membrane electrode assembly and the gas channel geometry.

关键词： Proton exchange membrane fuel cell Hierarchical model neural network Hybrid model

The role of FAST in pulsar timing arrays

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research in Astronomy and Astrophysics 2019年第2期19卷 39-54页

作者： George Hobbs Shi Dai richard n.manchester ryan M.Shannon Matthew Kerr Ke-Jia Lee ren-Xin Xu CSIrO Astronomy and Space Science Department of Astronomy School of Physics Peking University Kavli Institute for Astronomy and Astrophysics Peking University Max-Planck-Institut für radioastronomie

The Five-hundred-meter Aperture Spherical radio Telescope(FAST) will become one of the world-leading telescopes for pulsar timing array(PTA) research. The primary goals for PTAs are to detect(and subsequently study) ultra-low-frequency gravitational waves, to develop a pulsar-based time standard and to improve solar system planetary ephemerides. FAST will have the sensitivity to observe known pulsars with significantly improved signal-to-noise ratios and will discover a large number of currently unknown pulsars. We describe how FAST will contribute to PTA research and show that jitter-and timing-noise will be the limiting noise processes for FAST data sets. Jitter noise will limit the timing precision achievable over data spans of a few years while timing noise will limit the precision achievable over many years.

关键词： stars:pulsars gravitational waves

Hydrogen reduction and Microstructural Changes of ISF Hot Briquette

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昆明理工大学学报(自然科学版) 1996年第6期 104-113页

作者： Hua Yixin (Department of Metallurgy,Kunming University of Science and Technology,Kunming, Yunna 650093)Sale F.r(manchester Materials Science Centre,University of manchester and UMIST, manchester Ml 7HS,UK)

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关键词： reduction Microstructure ISF hot briquette

The Impact of Black Sea Sand Treatment Effectively reducing Different Type of Pain

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Open Journal of Therapy and rehabilitation 2024年第1期12卷 18-27页

作者： Mahmut Tokaç Abdulbari Bener Fatma nur Kesiktaş Bahar Dernek Semra Alkal Akkaya Zeynep Esra Akgün Department of Medicine and Education Unit School of Medicine Istanbul Medipol University Istanbul Türkiye Department of Biostatistics & Medical Informatics School of Medicine Istanbul Medipol University Istanbul Türkiye Department of Evidence for Population Health Unit School of Epidemiology and Health Sciences The University of Manchester Manchester UK Faculty of Medicine Health Sciences University Istanbul Physiotherapy Rehabilitation Training and Research Hospital Istanbul Türkiye Faculty of Medicine Health Sciences University Department of Physical Medicine and Rehabilitation Umraniye Training and Research Hospital Istanbul Türkiye Physical Medicine and rehabilitation Vatan Clinics School of Medicine Istanbul Medipol University Istanbul Türkiye

Purpose: Low back pain (LBP), Gonarthrosis, knee, and Carpal Tunnel Syndrome have been regarded as affecting more than three-quarters’ of individuals in their lifetime. The aim of this study was conducted to determine and compare the effects of topical patients with sand compared with control related to Gonarthrosis, LBP, knee, and Carpal Tunnel Syndrome pain. Methods: This is a prospective case and control designed study based on 101 pain case with Sand and 101 control subjects. The interventional groups in addition either topical sand or without sand 2 months after the intervention were assessed. We assessed tolerability of an established pain perception scale by the numeric rating Scale (nrS). Categorical variables were compared using the chi-square (χ2) test. The paired t-test was used to compare the two groups before and after the intervention. One-way analysis of variance (AnOVA) was employed for comparison of several group means. results: The study was based on 202 patients, 41 males (20.3%) and 161 females (79.7%). There were statistically significant differences between subjects with and without Sand in term of Gonarthrosis, rheumatoid Arthritis LBP, knee, and Carpal Tunnel Syndrome pain (p = 0.033). Majority of patients were over age 55 years old (55%) and females 78 (77.2%). The mean score of total pain experience before and after the intervention was 7.41 ± 1.1 for black sand, and 4.24 ± 2.38 for without sand as control group. The mean scores of these 5 groups were highly significant before and after the intervention (p There was statistically highly significant in regarding subjects with Sand as compared with those before Sand after treatment mean score specifically with gonarthrosis before pain 7.23 ± 1.86 vs after treatment 4.54 ± 2.18 p rheumatoid arthritis before 8.28 ± 1.48 vs after treatment 4.80 ± 3.71 p n before 8.42 ± 1.83 vs after treatment 4.37 ± 1.52 p nee pain before 8.93 ± 0.89 vs after treat

关键词： Therapies Sand LBP Musculoskeletal rheumatoid Arthritis Carpal Tunnel Syndrome

rescue from complications after pancreaticoduodenectomies at a low-volume Caribbean center:Value of tailored peri-pancreatectomy protocols

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 681-688页

作者： Shamir O Cawich Elijah Dixon Parul J Shukla Shailesh V Shrikhande rahul r Deshpande Fawwaz Mohammed neil W Pearce Wesley Francis Shaneeta Johnson Johann Bujhawan Department of Surgery University of the West IndiesSt Augustine 000000Trinidad and Tobago Department of Surgery Faculty of MedicineUniversity of CalgaryCalgaryAlberta T2N2T9Canada Department of Surgery Weill Cornell Medical CollegeNew YorkNY 10065United States Department of Surgical Oncology Tata Memorial CenterHomi Bhabha National UniversityMumbai 400012India Department of Surgery Manchester Royal InfirmaryManchester M139WLUnited Kingdom University Surgical Unit Southampton General HospitalSouthampton SO166YDUnited Kingdom Department of Surgery University of the West IndiesNassau N-1184Bahamas Department of Surgery Morehouse School of MedicineAtlantaGA 30310United States Department of Surgery General Hospital in Port of SpainPort of Spain 000000Trinidad and Tobago

BACKGrOUnD Pancreaticoduodenectomy(PD)is a technically complex operation,with a re-latively high risk for *** ability to rescue patients from post-PD complications is as a recognized quality *** protocols were instituted at our low volume facility in the year *** To document the rate of rescue from post-PD complications with tailored protocols in place as a measure of *** A retrospective audit was performed to collect data from patients who experienced major post-PD complications at a low volume pancreatic surgery unit in Trinidad and Tobago between January 1,2013 and June 30,***-dardized definitions from the International Study Group of Pancreatic Surgery were used to define post-PD complications,and the modified Clavien-Dindo classification was used to classify post-PD *** Over the study period,113 patients at a mean age of 57.5 years(standard deviation[SD]±9.23;range:30-90;median:56)underwent PDs at this *** complications were recorded in 33(29.2%)patients at a mean age of 53.8 years(SD:±7.9).Twenty-nine(87.9%)patients who experienced major morbidity were salvaged after aggre-ssive treatment of their ***(3.5%)died from bleeding pseudoaneurysm(1),septic shock secondary to a bile leak(1),anastomotic leak(1),and myocardial infarction(1).There was a significantly greater salvage rate in patients with American Society of Anesthesiologists scores≤2(93.3%vs 25%;P=0.0024).COnCLUSIOn This paper adds to the growing body of evidence that volume alone should not be used as a marker of quality for patients requiring *** low volumes at our facility,we demonstrated that 87.9%of patients were rescued from major *** attributed this to several factors including development of rescue protocols,the competence of the pancreatic surgery teams and continuous,and adaptive learning by the entire institution,cul-minating in the development of tailored peri-pancreatectomy protoc

关键词： Pancreas Complication rescue Failure Morbidity Mortality Pancreaticoduodenectomy