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Childhood malaria in the Niger delta area of Nigeria:mothers/care givers'perception,definition and treatment practices

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Asian Pacific Journal of Tropical Medicine 2009年第3期2卷 52-58页

作者： Idogun E.Sylvester Airauhi l.u Department of Chemical Pathology University of Benin Teaching HospitalBenin City Department of Medical Microbiology Biology University of Benin Teaching HospitalBenin City

Objective:The objective of the study was to evaluate mothers/care givers perception of malaria,their treatment practices and the effects on the outcome of ***:Four hundred and sixty children were enrolled and their mothers/care givers *** children were screened for malaria parasitaemia and there after,blood specimens were obtained for biochemical and haematological evaluation from those children who met the criteria and tested positive to *** *** cell volume,electrolytes,urea, creatinine,plasma glucose,and serum bilirubin were ***:A total of 460 children were studied, 233(50.7%) males and 227(49.3%) *** malaria cases were 112(24.3%) and severe malaria 348(75.7%).Those who presented early 106(23.0%) and those who presented late 354(77.0%).Perception and definition of malaria as well as the treatment seeking behaviors vary significantly with the level of education of the mothers and care *** without formal education 68(51.9%) wrongly perceived that the etiology of malaria can only be diagnosed by native doctors compared to those with primary six education 61 (26.5%) and junior secondary education 10(10.1%).Only 43(9.3%) gave the correct dose of chloroquine syrup to their sick children,while 32(7.0%) gave at sub optimal ***:Wrong perception of malaria especially the complicated malaria and wrong treatment practices are major contributory factors to the high mortality and morbidity of malaria in *** is therefore a need for health education to correct the wrong ideas about the cause and treatment practices of malaria as part of malaria control programme.

关键词： Childhood malaria Mothers/Caregivers Perception and treatment practices Nigeria

Quantum public-key crypto via EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 58-63页

作者： Xiang-Qun Fu Hong-Wei li Jian-Hong Shi Tan li Wan-Su bao Henan Key laboratory of Quantum Information and Cryptography Information Engineering University Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

With the development of quantum computing technology, quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key cryptography. This paper designs a quantum trapdoor one-way function via EPR pairs and quantum measurements. Based on this, a new quantum public-key cryptosystem is presented, which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext attack. Compared with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition, which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2014年第3期57卷 418-423页

作者： l Yan bao JingDong School of Applied Science Taiyuan University of Science and Technology Department of Physics Beijing Normal University

The correlated levy flight is studied analytically in terms of the fractional Fokker-Planck equation and simulated numerically by using the langevin equation, where the usual white ltvy noise is generalized to an Ornstein-uhlenbeck levy process （OAlP） with a correlation time τc. We analyze firstly the stable behavior of OulP. The probability density function of ltvy flight particle driven by the OulP in a harmonic potential is exactly obtained, which is also a ltvy-type one with Tc-dependence width; when the particle is bounded by a quartic potential, its stationary distribution has a bimodality shape and becomes noticeable with the increase of τc.

关键词： l3vy flight OulP fractional Fokker-Planck equation

Exploring Soil layers and Water Tables with Ground-Penetrating Radar

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Pedosphere 2004年第3期14卷 273-282页

作者： K.ROTH u.WOllSCHlAGER CHENGZhu-Hua ZHANGJia-bao InstituteofEnvironmentalPhysics UniversityofHeidelbergHeidelberg（Germany） InstituteofSoilScience ChineseAcademyofSciencesNanjing210008（China）

Ground-penetrating radar (GPR) has been used predominantly for environments with low electrical conductivity like freshwater aquifers, glaciers, or dry sandy soils. The objective of the present study was to explore its application for mapping in subsurface agricul.ural soils to a depth of several meters. For a loamy sand and a clayey site on the North China Plain, clay inclusions in the sand were detected; the thickness, inclination, and continuity of the confining clay and silt layers was assessed; and a local water table was mapped. Direct sampling (soil coring and profiling) in the top meter and independent measurement of the water table were utilized to confirm the findings. Also, effective estimates of the dielectric number for the site with the dielectric number of moist clayey soils depending strongly on frequency were obtained. Thus, important properties of soils, like the arrangement and type of layers and in particular their continuity and inclination, could be explored with moderate efforts for rather large areas to help find optimal locations for the time-consuming and expensive measurements which would be necessary to detail a model of the subsurface.

关键词： ground-penetrating radar soil layers water table

Probabilistic assessment of overcooling risk for a novel extra-low temperature dedicated outdoor air system for Hong Kong office buildings

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Building Simulation 2021年第3期14卷 633-648页

作者： Yani bao W.l.lee Jie Jia Department of Building Services Engineering The Hong Kong Polytechnic UniversityHong KongChina Department of Built Environment and Energy utilization Engineering Taiyuan University of TechnologyTaiyuan 030024China

Overcooling causes thermal discomfort and wastes *** of a novel dedicated outdoor air system(DOAS)consisting of a multi-stage direct expansion coil to generate extra-low temperature(XT)outdoor air to handle the entire space cooling demand for better energy and humidity control has been confirmed in previous *** these studies,the terminal system was assumed using variable air volume(VAV)without *** conventional VAV system without reheating has overcooling *** is associated with uncertain fluctuations of operating ***,virtually no study has been done to investigate its overcooling risk,and how it is compared with *** this study,a rigorous probabilistic approach is proposed to account for the uncertain fluctuations of operating characteristics to assess their overcooling *** Carlo simulations with 10,000 interactions was used for risk analysis.A morphing method was employed to develop 10,000 weather files that could give an accurate prediction of future variations in yearly weather *** datasets were used to develop the probability distribution functions to account for the daily variations in use *** most probable operating characteristics were input to EnergyPlus for hour-by-hour *** annual cooling load profile formulated by the probabilistic approach was successfully validated by in-situ *** probabilistic assessment results show that XT-DOAS has far less overcooling hours and lower long-term percentage of dissatisfied than the conventional VAV *** results also indicate that the proposed probabilistic approach is useful for a robust system performance evaluation.

关键词： overcooling risk Monte Carlo simulation uncertainty analysis extra-low temperature system VAV system

Inertial lévy Flight with Nonlinear Friction

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Chinese Physics letters 2011年第11期28卷 1-3页

作者： lÜYan bao Jing-Dong Department of Physics Beijing Normal UniversityBeijing 100875

lévy flight with nonlinear friction is *** to the occurrence of extremely long jumps lévy flights often possess infinite variance and are physically problematic if describing the dynamics of a particle of finite ***,by introducing nonlinear friction,we show that the stochastic process subject to lévy noise exhibits finite variance,leading to a well-defined kinetic *** the force-free field,normal diffusion behavior is observed and the diffusion coefficient decreases with lévy index𝜇.Furthermore,we find a kinetic resonance of the particle in the harmonic potential to the external oscillating field in the generally underdamped region and the value of the linear friction𝛾0 determines whether resonance occurs or not.

关键词： variance diffusion finite

Wear of semi-solid rheocast SiC_p/Al metal matrix composites

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中国有色金属学会会刊：英文版 2010年第S3期20卷 852-856页

作者： u.A.CuRlE l.IVANCHEV Materials Science and Manufacturing Council for Scientific and Industrial Research(South Africa)

Rheocasting of plates in Al alloy 359 reinforced with SiC at 11%,27% and 50%(volume fractions) exhibits the capability of the council for scientific and industrial research-rheocasting system(CSIR-RCS) in rheo-processing and high pressure die casting of SiC metal matrix *** metal matrix consisting of nearly spherical proeutectic α(Al) globules was *** of fibrous eutectic silicon took place upon heat treatment of the as-cast metal matrix composites(MMCs).Hardness increases as the volume fractions of SiC *** rates of the MMCs in the F and T6 heat treatment conditions were assessed with a metallographic preparation *** is found that the 11% SiC MMC wear rate is higher on SiC abrasives compared with the 50% SiC MMC wear rate due to wear of the aluminum *** trend is reversed on diamond abrasives due to pull-out of the irregular shaped composite *** 50% SiC MMC suffers from composite particle fracture porosity after high pressure die casting(HPDC).

关键词： CSIR-RCS HPDC SiC F condition T6 condition wear rate hardness porosity

On the detection of closed orbits in time-dependent systems by using double-pulse lasers

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Communications in Theoretical Physics 2020年第9期72卷 111-117页

作者： S u Khan M l Du Institute of Theoretical Physics Chinese Academy of Sciences.Beijing 100190China university of Chinese Academy of Sciences Beijing100049China

In the photodetachment of atoms or negative ions by a double-pulse laser, the first pulse of the double-pulse laser generates waves and the delayed second pulse may detect them. The phenomenon of the excitation and detection of waves by a double-pulse laser can be used to identify the closed orbits in the system. We demonstrate this phenomenon with a negative hydrogen ion(H^-) by analyzing the total population excited by a double-pulse laser in a timedependent field for different physical parameters. By analyzing the total excited population using a double-pulse laser, we can uncover all the closed orbits existing in the system. We demonstrate that this can be realized by scanning the first pulse position and the time delay between the two pulses.

关键词： double-pulse laser detection of closed orbits photodetachment spectra time-dependent systems

Flow instability of nanofuilds in jet

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Applied Mathematics and Mechanics(English Edition) 2015年第2期36卷 141-152页

作者： Yi XIA Jianzhong lIN Fubing bao T.l.CHAN Department of Mechanics State Key Laboratory of Fluid Power Transmission and ControlZhejiang University Institute of Fluid Mechanics China Jiliang University Department of Mechanical Engineering The Hong Kong Polytechnic University

The flow instability of nanofluids in a jet is studied numerically under various shape factors of the velocity profile, Reynolds numbers, nanoparticle mass loadings,Knudsen numbers, and Stokes numbers. The numerical results are compared with the available theoretical results for validation. The results show that the presence of nanoparticles enhances the flow stability, and there exists a critical particle mass loading beyond which the flow is stable. As the shape factor of the velocity profile and the Reynolds number increase, the flow becomes more unstable. However, the flow becomes more stable with the increase of the particle mass loading. The wavenumber corresponding to the maximum of wave amplification becomes large with the increase of the shape factor of the velocity profile, and with the decrease of the particle mass loading and the Reynolds number. The variations of wave amplification with the Stokes number and the Knudsen number are not monotonic increasing or decreasing, and there exists a critical Stokes number and a Knudsen number with which the flow is relatively stable and most unstable,respectively, when other parameters remain unchanged. The perturbation with the first azimuthal mode makes the flow unstable more easily than that with the axisymmetric azimuthal mode. The wavenumbers corresponding to the maximum of wave amplification are more concentrated for the perturbation with the axisymmetric azimuthal mode.

关键词： nanoparticle-laden jet flow hydrodynamic instability Stokes number Knudsen number particle mass loading