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The neutron star zoo

Frontiers of physics 2013年第6期8卷 679-692页

作者： Alice k. Harding Astrophysics Science Division NASA Goddard Space Flight Center Greenbelt MD 20771 USA

Neutron stars are a very diverse population, both in their observational and their physical properties. They prefer to radiate most of their energy at X-ray and gamma-ray wavelengths. But whether their emission is powered by rotation, accretion, heat, magnetic fields or nuclear reactions, they are all different species of the same animal whose magnetic field evolution and interior composition remain a mystery. This article will broadly review the properties of inhabitants of the neutron star zoo, with emphasis on their high-energy emission.

关键词： stars neutron stars pulsars binary stars

Elimination of boundary effect for laminated overburden model in pillar stability analysis

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Journal of Central South University 2016年第6期23卷 1468-1473页

作者：张鹏 k. A. Heasley Carlson Software Watertown MA 02472 USA Department of Mining Engineering West Virginia University WV 26505 USA

The laminated overburden model(La Model)has been widely used for pillar design and stability *** a boundary element program,the La Model program is sensitive to the boundary condition,which should be considered before creating the *** eliminate the boundary effect in a La Model pillar stability analysis,a suitable boundary buffer zone is needed around the model *** radius of influence(R)and the abutment load extent(D)are two major factors that affect the stresses and displacements calculated in LaM *** determine the optimum buffer zone extent,a database of case histories was analyzed using the La Model *** for R and D were varied until a buffer zone having negligible influence on the pillar stability factor(SF)of the active mining zone(AMZ)was determined.

关键词： pillar stability boundary effect LaModel numerical simulation room-and-pillar

Unveiling the impact:COVID-19's influence on bacterial resistance in the k.ngdom of Bahrain

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World Journal of Virology 2025年第1期14卷 83-98页

作者： Nermin k.Saeed Safiya k.Almusawi Noor A Albalooshi Mohammed Al-Beltagi Medical Microbiology Section Department of PathologySalmaniya Medical ComplexGovernmental HospitalsManama 12Bahrain Medical Microbiology Section Department of PathologyRoyal College of Surgeons in Ireland-Medical University of BahrainBusaiteen 15503MuharraqBahrain Department of Paediatrics Faculty of MedicineTanta UniversityTanta 31511AlghrabiaEgypt Department of Pediatric University Medical CenterKing Abdulla Medical CityArabian Gulf UniversityManama 26671AlgharbiaBahrain

BACk.ROUND Antibiotic resistance is a growing global health threat,and understanding local trends in bacterial isolates and their susceptibility patterns is crucial for effective infection control and antimicrobial *** coronavirus disease 2019(COVID-19)pandemic has introduced additional complexities,potentially influencing these *** To analyze trends in bacterial isolates and their antibiotic susceptibility patterns at Salmaniya Medical Complex from 2018 to 2023,with a specific focus on the impact of the COVID-19 pandemic on these *** A retrospective analysis of microbiological data was conducted,covering the period from 2018 to *** study included k.y bacterial pathogens such as Escherichia coli(***),k.ebsiella pneumoniae,Acinetobacter baumannii,Pseudomonas aeruginosa,and Staphylococcus aureus,among *** antibiotic susceptibility profiles of these isolates were assessed using standard laboratory *** contextualize the findings,the findings were compared with similar studies from other regions,including China,India,Romania,Saudi Arabia,the United Arab Emirates,Malaysia,and United *** The study revealed fluctuating trends in the prevalence of bacterial isolates,with notable changes during the COVID-19 *** example,a significant increase in the prevalence of Staphylococcus aureus was observed during the pandemic years,while the prevalence of *** showed a more variable *** resistance rates varied among the different pathogens,with a concerning rise in resistance to commonly used antibiotics,particularly among k.ebsiella pneumoniae and ***,the study identified an alarming increase in the prevalence of multidrug-resistant(MDR)strains,especially within k.ebsiella pneumoniae and *** *** impact of the COVID-19 pandemic on these trends was evident,with shifts in the frequency,resistance patterns,and the emergence of MDR bacteria among several k.y ***

关键词： Multidrug-resistant organisms Antibiotic susceptibility COVID-19 pandemic Antimicrobial stewardship Bacterial isolates Salmaniya Medical Complex Bahrain

Solvent effects on hydrogen bonding between primary alcohols and esters

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1928-1931页

作者： DHARMALINGAM k. RAMACHANDRAN k. SIVAGURUNATHAN P. Department of Physics Annamalai University Annamalai Nagar 608002 Tamilnadu India

The interaction by hydrogen bond formation of some primary alcohols （ l-heptanol, l-octanol and l-decanol） with esters （methyl methacrylate, ethyl methacrylate and butyl methacrylate） was investigated in non-polar solvents viz., n-heptane, CC14 and benzene by means of FTIR spectroscopy. Formation constants and free energy changes of complex formation were determined. The dependence of the equilibrium constants and free energy changes of complex formation on the alk.l chain length of both the alcohols and esters are discussed. The solvent interaction between the solute and solvent. effect on the hydrogen bond formation is discussed in terms of specific

关键词： FTIR spectroscopy Primary alcohols Esters Hydrogen bonding Solvent effect

A cellular automata traffic flow modeling of desired speed variability

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Chinese Physics B 2013年第1期22卷 574-577页

作者： k. Bentaleb k. Jetto H. Ez-Zahraouy A. Benyoussef Laboratoire de Magnétisme et de Physique des Hautes Energies associéau CNRST (URAC 12) Département de physique B.P. 1014 Facultédes sciences Université Mohammed V Agdal Rabat Morocco Ecole Hassania des Travaux Publics k. 7 Route d'El Jadida BP8108 Oasis Casablanca Morocco Institute of Nanomaterials and Nanotechnologies INANOTECH MACsIR Rabat Morocco Hassan II Academy of Science and Technology Rabat Morocco

The satisfaction rate of desired velocity in the case of a mixture of fast and slow vehicles is studied by using a cellular automaton method. It is found that at low density the satisfaction rate depends on the maximal velocity. However, the behavior of the satisfaction rate as a function of the coefficient of variance is independent of the maximal velocity. This is in good agreement with empirical results obtained by Lipshtat [Phys. Rev. E 79 066110 （2009）]. Furthermore, our numerical result demonstrates that at low density the satisfaction rate tak.s higher values, whereas the coefficient of variance is close to zero. The coefficient of variance increases with increasing density, while the satisfaction rate decreases to zero. Moreover, we have also shown that, at low density the coefficient variance depends strongly on the probability of overtak.ng.

关键词： traffic celluar automata satisfaction coefficient desired speed

On the invariance of time-dependent Hamilton's functions

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Acta Mechanica Sinica 2005年第5期21卷 511-513页

作者： Q. k. Ghori Department of Mathematics COMSATS Institute of Information TechnologyIslamabad Pakistan

The general framework.of Poincarè＇s formalism is used to establish the connection between conservation laws and invariance properties of Hamilton＇s function under infinitesimal transformations when these laws and t... 详细信息

关键词： Conservation law . Poincarè's formalism .Infinitesimal transformation

INVERTING GENERATING FUNCTIONS WITH INCREASED NUMERICAL PRECISION-A COMPUTATIONAL EXPERIENCE

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Journal of Systems Science and Systems Engineering 2011年第4期20卷 475-494页

作者： Nam k. k.M Mohan L. CHAUDHRY Bong k. YOON k.lhwan k.M Department of Industrial Engineering Chonnam National University Department of Mathematics and Computer Science Royal Military College of Canada Defense Management College Korea National Defense University Internet Research Lab. Electronics and Telecommunications Research Institute

In this paper, we consider the numerical inversion of a variety of generating functions （GFs） that arise in the area of engineering and non-engineering fields. Three classes of GFs are tak.n into account in a comprehensive manner： classes of probability generating functions （PGFs） that are given in rational and non-rational forms, and a class of GFs that are not PGFs. Among others, those PGFs that are not explicitly given but contain a number of unk.owns are largely considered as they are often encountered in many interesting applied problems. For the numerical inversion of GFs, we use the methods of the discrete （fast） Fourier transform and the Taylor series expansion. Through these methods, we show that it is remark.bly easy to obtain the desired sequence to any given accuracy, so long as enough numerical precision is used in computations. Since high precision is readily available in current software pack.ges and programming languages, one can now lift, with little effort, the so-called Laplacian curtain that veils the sequence of interest. To demonstrate, we tak. a series of representative examples： the PGF of the number of customers in the discrete-time Geo^X/Geo/c queue, the same in the continuous-time M^X/D/c queue, and the GFs arising in the discrete-time renewal process.

关键词： Queuing applied probability numerical inversion generating function

Experimental investigation on strip inserts in a circular tube heat transfer effect of conical under laminar flow

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Frontiers in Energy 2016年第2期10卷 136-142页

作者： M. ARULPRAk.SAJOTHI k. ELANGOVAN k. HEMA CHANDRA REDDY S. SURESH Department of Mechanical Engineering Jawaharlal Nehru Technologi-cal University Anantapur Anantapur 515002 India Department of Mechanical Engineering Cambridge Institute ofTechnology Bangalore 560036 India Department of Mechanical Engineering National Institute of Technology Trichy 620015 India

The aim of this paper is to observe the Nusselt number and friction factor behavior of the circular tube with conical strip inserts as turbulators in a laminar flow condition, using staggered and non-staggered conical strips with three different twist ratios （Y = 2, 3 and 5）. The conical strip is inserted in the forward and back.ard direction individually compared to the flow of water which is the work.ng fluid. The results indicate that the conical strip inserts increases the Nusselt number when compared to the plain surface tube. It is observed that the strip geometry has a major effect on the thermal performance of the circular tube. On examination of different strips for determining the enhancement of Nusselt number, the staggered conical strip with the twist ratio of Y = 3 has given a better result compared to the other two strips. Finally, correlations have been derived using regression analysis for predicting the Nusselt number and friction factor.

关键词： Nusselt number friction factor conical strip

Demonstration of essentiality of entanglement in a Deutsch-lik. quantum algorithm

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Science China(Physics,Mechanics & Astronomy) 2018年第6期61卷 1-7页

作者： He-Liang Huang Ashutosh k. Goswami Wan-Su Bao Prasanta k. Panigrahi Chinese Academy Sciences Centre for Excellence and Synergetic Innovation Centre in Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 China Hefei National Laboratory for Physical Sciences at Microscale Department of modern Physics University of Science and Technology of China Hefei 230026 China Indian Institute of Science Education and Research k.lk.ta Mohanpur 741 246 India

Quantum algorithms can be used to efficiently solve certain classically intractable problems by exploiting quantum ***, the effectiveness of quantum entanglement in quantum computing remains a question of debate. This study presents a new quantum algorithm that shows entanglement could provide advantages over both classical algorithms and quantum algorithms without entanglement. Experiments are implemented to demonstrate the proposed algorithm using superconducting *** show the viability of the algorithm and suggest that entanglement is essential in obtaining quantum speedup for certain problems in quantum computing. The study provides reliable and clear guidance for developing useful quantum algorithms.

关键词： quantum computing quantum entanglement quantum algorithm Deutsch's problem