嵌入式电源控制器设计

为实现对现场设备的远程监测,采用内嵌RTOS(Nut/OS)和TCP/lP协议的嵌入式电源控制器。自行设计部分软、硬件,通过以太网编程实现系统的远程控制。

应用于HIRFL-CSR中的RS485通讯路由器

本文介绍了为适应HIRFL-CSR(兰州重离子加速器冷却储存环)工程自动化控制现场的通信要求而自主研发的一种通信设备,以及系统硬件电路设计、控制软件设计、工作方式和特点。此设备可快速组建RS485通信网络并且接入以太网,兼容Ethernet、RS232和RS485通信标准协议,特别是增加了光纤接口方便地接入工业光纤通信网络,进一步扩展了其使用范围。此设备在HIRFL-CSR加速器和储存环控制系统中被广泛使用,在使用中表明可满足系统自动控制通信要求。此设备具有实现简单、易于维护、可扩展性好及成本低廉等特点,在其它自动化工业控制领域也有一定的推广空间。

重离子加速器注入器电源控制器的设计；Design of digital power control system applied in sector focusing cyclotron

设计了一种应用于兰州重离子加速器注入器的电源控制器,该控制器基于微处理器AT-mega128,结合MAX7000系列的复杂可编程器件和RTL8019AS网关芯片来实现对电源系统的控制,并通过RS-232总线实现与上位机的串口通信。应用结果表明,该控制器具有良好的通用性、灵活性、可远程控制及性能稳定等特点,实现了注入器磁铁电源10-4量级的幅度稳定性,使注入器引出的束流强度、束流品质、束流稳定性和供束效率等得到很大的提高。

Uniform AMoO(4):Ln (A = Sr2+, Ba2+; Ln = Eu3+, Tb3+) submicron particles: Solvothermal synthesis and luminescent properties

Rare-earth ions (Eu3+, Tb3+) doped AMoO(4) (A = Sr, Ba) particles with uniform morphologies were successfully prepared through a facile solvothermal process using ethylene glycol (EG) as protecting agent. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS), Fourier transform infrared spectroscopy (FT-IR), photoluminescence (PL) spectra and the kinetic decays were performed to characterize these samples. The XRD results reveal that all the doped samples are of high purity and crystallinity and assigned to the tetragonal scheelite-type structure of the AMoO(4) phase. It has been shown that the as-synthesized SrMoO4:Ln and BaMoO4:Ln samples show respective uniform pea nut-like and oval morphologies with narrowsize distribution. The possible growth process of the AMoO(4):Ln has been investigated in detail. The EG/H2O volume ratio, reaction temperature and time have obvious effect on themorphologies and sizes of the as-synthesized products.

多波多分量地震资料走时近似方法的研究与应用

Compared with the conventional P wave, multi-component seismic data can markedly provide more information, thus improve the quality of reservoir evaluation like formation evaluation etc. With PS wave, better imaging result can be obtained especially in areas involved with gas chimney and high velocity formation. However, the signal-to-noise of multi-component seismic data is normally lower than that of the conventional P wave seismic data, while the frequency range of converted wave is always close to that of the surface wave which adds to the difficulty of removing surface wave. To realize common reflection point data stacking from extracted common conversion point data is a hard nut to crack. The s wave static correction of common receiver point PS wave data is not easy neither. In a word, the processing of multi-component seismic data is more complicated than P wave data. This paper shows some work that has been done, addressing those problems mentioned above. (1) Based on the AVO feature of converted wave, this paper has realized the velocity spectrum of converted waves by using Sarkar’s generalized semblance method taking into account of AVO factor in velocity analysis. (2)We achieve a method of smoothly offset division normal method.Firstly we scan the stacking velocities in different offset divisions for a t0, secondly obtain some hyperbolas using these stacking velocities, then get the travel time for every trace using these hyperbolas; in the end we interpolate the normal move out between two t0 for every trace. (3) Here realize a method of stepwise offset division normal moveout.It is similar to the method of smoothly offset division normal moveout.The main difference is using quadratic curve, sixth order curve or fraction curve to fit these hyperbolas. (4)In this paper, 4 types of travel time versus distance functions in inhomogeneous media whose velocity or slowness varies with depth and vertical travel time have been discussed and used to approximate reflection travel time. The errors of ray path and travel time based on those functions in four layered models were analyzed, and it has shown that effective results of NMO in synthetic or real data can be obtained. (5) The velocity model of converted PS-wave can be considered as that of P -wave based on the ghost source theory, thus the converted wave travel time can be approximated by calculation from 4 equivalent velocity functions: velocity or slowness vary linearly with depth or vertical travel time. Then combining with P wave velocity analysis, the converted wave data can be corrected directly to the P-wave vertical travel time. The improvements were shown in Normal Move out of converted waves with numerical examples and real data. (6) This paper introduces the methods to compute conversion point location in vertical inhomogeneous media based on linear functions of velocity or slowness versus depth or vertical travel time, and introduce three ways to choose appropriate equivalent velocity methods, which are velocity fitting, travel time approximation and semblance coefficient methods.

Mesoporous spinel MgAl2O4 prepared by in situ modification of boehmite sol particle surface: I Synthesis and characterization of the unsupported membranes

Mesoporous spinel membranes as ultrafiltration membranes were prepared through a novel sol-gel technique. By in situ modification of the sol particle surface during the sol-gel process, control of the material structure on a nanometer scale from the earliest stages of processing was realized. Nano-particles with a chocolate-nut-like morphology, i.e. spinel MgAl2O4 as a shell and gamma -Al2O3 as a core, were first revealed by HRTEM results. The formation of the spinel phase was confirmed by X-ray diffraction (XRD). N-2 adsorption-desorption results showed that the mesoporous membranes had a narrow pore size distribution. (C) 2001 Elsevier Science B.V. All rights reserved.

Monopoles for gravitation and for higher spin fields

We consider massless higher spin gauge theories with both electric and magnetic sources, with a special emphasis on the spin two case. We write the equations of motion at the linear level (with conserved external sources) and introduce Dirac strings so as to derive the equations from a variational principle. We then derive a quantization condition that generalizes the familiar Dirac quantization condition, and which involves the conserved charges associated with the asymptotic symmetries for higher spins. Next we discuss briefly how the result extends to the nonlinear theory. This is done in the context of gravitation, where the Taub-NUT solution provides the exact solution of the field equations with both types of sources. We rederive, in analogy with electromagnetism, the quantization condition from the quantization of the angular momentum. We also observe that the Taub-NUT metric is asymptotically flat at spatial infinity in the sense of Regge and Teitelboim (including their parity conditions). It follows, in particular, that one can consistently consider in the variational principle configurations with different electric and magnetic masses. © 2006 The American Physical Society.

Un nuevo perfil de productores de nogal pecán (Carya illinoensis) : los Productores Hobby

p.203-212

Glutamine as a modulator of the immune system of critical care patients:effect on Toll-like receptor expression. A preliminary study

We evaluated the expression of Toll-like receptors 2 and 4 (TLR-2 and TLR-4) in circulating monocytes from peripheral blood of critical care patients treated with and without glutamine. Because no research has been published to date on the effect of glutamine on TLR receptors in critical patients, it was determined in an initial sample of 30 patients.

Green tea minimally affects biomarkers of inflammation in obese subjects with metabolic syndrome

Green tea (Camellia sinensis) has shown to exert cardioprotective benefits in observational studies. The objective of this clinical trial was to assess the effects of green tea on features of metabolic syndrome and inflammation in obese subjects.

Numerical Simulation of Tanpura String Vibrations

A numerical model of a tanpura string is presented, based on a recently developed, stability-preserving way of incorporating the non-smooth forces involved in the impactive distributed contact between the string and the bridge. By defining and modelling the string-bridge contact over the full length of the bridge, the simulated vibrations can be monitored through the force signals at both the bridge and the nut. As such it offers a reference model for both measurements and sound synthesis. Simulations starting from different types of initial conditions demonstrate that the model reproduces the main characteristic feature of the tanpura, namely the sustained appearance of a precursor in the force waveforms, carrying a band of overtones which decrease in frequency as the string vibrations decay. Results obtained with the numerical model are used to examine, through comparison, the effect of the bridge and of the thread on the vibrations.

Reconstructing ethical conduct within financial firms

This chapter explores whether ethical cultures can be created within a financial market context. Ongoing regulatory and legal actions, and press coverage of these, suggest that a definition of ethical problems in terms of ‘rogue traders’ and ‘bad apples’ would be inadequate, since entire business areas have been resorting to collusive illegal behaviour. The concept of ‘bad barrels’ seems to capture the situation rather better: the culture of firms fails to discourage transgression and indeed supports it. Unpacking the links between regulatory objectives and the cultural settings of firms and their employees, this chapter questions the chances of success of measures such as enhanced controls on individuals and restructured reward mechanisms. Financial firms typically have very flat, nodal structures, within which traders conceptualise themselves as an elite, in contrast to back office staff and also in contrast to managers. Traders’ functions and their occupational mobility mean that their linkages and attachments may be much stronger with others outside ‘their’ firm than their firm and those within it. Performance, camaraderie and their linkages are important in all work situations, yet all the more so for traders in financial markets. Thus, whether regulators and senior management combine to send a clear and consistent message to traders – or whether the logic of the financial marketplace leads some firms to continue send conflicting or ambivalent messages to them – misconduct is likely to continue to be a tough nut to crack.

Nutritional modulation of innate immune parameters in the epidermal mucus of Senegalese sole (Solea senegalensis)=Influência da dieta nos parâmetros da resposta imunitária inata do muco de linguado (Solea senegalensis)

Dissertação mest., Biologia Marinha, Universidade do Algarve, 2008

A autenticidade como determinante da fidelização: o caso do litoral alentejano

Este estudo analisa a relevância do conceito de autenticidade, do ponto de vista da gestão, num destino turístico de tipo “sol e praia”, onde a autenticidade constitui a sua principal vantagem comparativa. Para o efeito, propomos um modelo em que a autenticidade constitui o mediador chave entre as motivações culturais e a satisfação, as intenções comportamentais e a fidelização. O modelo foi empiricamente testado através da aplicação de uma amostra de 245 questionários recolhidos na área geográfica correspondente à NUT III – Alentejo Litoral. O Alentejo é a região mais tradicional de Portugal, onde o oceano contrasta com a calma e a beleza da paisagem rural que dita a forma como as pessoas vivem e recebem os visitantes. Para a realização do estudo foi aplicado um modelo de equações estruturais (MEE) utilizando o SmartPLS 2.0 M3. Os resultados indicam que as motivações culturais constituem um importante antecedente da autenticidade baseada nos atributos e da autenticidade existencial, as quais exercem, por sua vez, uma significativa influência na satisfação. Este último constructo revela também uma grande influência directa e indirecta (via intenções comportamentais) na fidelização. As implicações teóricas e de gestão foram discutidas mostrando que a preservação e valorização dos traços de autenticidade da região podem contribuir para reforçar a satisfação dos turistas e a competitividade do destino.

Betel Use in Pregnancy

Thesis (Master's)--University of Washington, 2015