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Basic Parameters (basic + parameter)
Selected AbstractsSensitive In0.53Ga0.47As/InP (SI) magnetic field sensorsPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 2 2004T. Przes, awski Abstract The usefulness of InGaAs/InP heterostructures for magnetic field sensor applications has been studied. Basic parameters of the Hall and magnetoresistive devices have been determined. Magnetic field sensitivities in a wide temperature range from 3.5 K to 300 K for layers with different carrier concentration from 2 , 1020 m,3 to 8 , 1023 m,3 have been measured. It is concluded that optimized lattice-matched InGaAs/InP heterostructures can be used as very sensitive magnetic field sensors. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The young open cluster Trumpler 3ASTRONOMISCHE NACHRICHTEN, Issue 3 2010G. Maciejewski Abstract We present a photometric and spectroscopic study of the poorly investigated open cluster Trumpler 3. Basic parameters such as the age of 70 ± 10 Myr, the color excess E (B , V) = 0.30 ± 0.02 mag, the distance of 0.69 ± 0.03 kpc and the limiting radius of 12, were redetermined and compared with previous preliminary studies. The distance of 0.65 ± 0.09 kpc was determined independently by spectral parallaxes. Simultaneously, our analysis allowed us to estimate a total number of members to be Ntot = 570 ± 90 and a total mass of the cluster to be Mtot = 270 ± 40 M,. We also determined a state of cluster's dynamical evolution. We conclude that Trumpler 3 is a young low-massive stellar ensemble with a typical mass function slope, located near to the outer edge of the Galaxy's Orion Spur. As a result of a wide-field search for short period variable stars, 24 variables were discovered in the cluster's area. Only one of them , a variable of the , -Dor type , was found to be a likely cluster member (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Recognition of resonance in long radial transmission lines with static VAR compensation using travelling wavesEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 1 2005Ljubivoje M. Popovi Abstract This paper presents an analytical procedure for estimation of resonance frequencies in long-distance radial transmission lines with static VAR compensation. The development of the procedure is based on a new approach in solving this problem. It employs the fact that the phenomenon is characterized by an algebraic sum of travelling current waves at the beginning of the line. Relatively simple analytical expressions are obtained by considering the phase angles of only one direct and only one corresponding reflected wave. Besides enabling a simpler and faster solution of the problem under various realistic conditions, the obtained analytical expressions also offer more direct analytical insight into the interplay of basic parameters. Copyright © 2005 John Wiley & Sons, Ltd. [source] Determining elastic constants of transversely isotropic rocks using Brazilian test and iterative procedureINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 3 2008Yen-Chin Chou Abstract The elastic constants of rocks are the basic parameters for rock mechanics, and play a very important role in engineering design. There are many laboratory methods to determine the elastic constants of transversely isotropic rocks, and the Brazilian test is a popular method. This paper presented a method combination of the Brazilian test, back calculation, and iterative procedure to evaluate the five independent elastic constants of transversely isotropic rocks in laboratory. The strain data at the centre of discs were obtained using Brazilian test. The stresses at the centre of discs were computed using numerical programs. By using back calculation, the temporary elastic constants were computed after the stresses and stains were substituted into elastic mechanics equations. After iterative procedure, the convergent values of the elastic constants can be obtained. One numerical example and three experimental cases were proposed to show the applicability of this method. The convergent values of the five independent elastic constants can be obtained in no more than 10 iterative cycles. The results coming from numerical analysis method exhibited satisfactory outcome in accordance with those of generalized reduced gradient method. The merits of this method include convenient specimen preparation of the Brazilian test, simple iterative procedure, and readily available commercially numerical programs, so that this method can be easily popularized in research and engineering analysis. Copyright © 2007 John Wiley & Sons, Ltd. [source] Treatment of textile dye wastewater by using an electrochemical bipolar disc stack reactorJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 10 2004Karuppan Muthukumar Abstract Textile dye house wastewater from a reactive dye processing unit was treated by using an electrochemical oxidation technique. The experiments were carried out in an electrochemical bipolar disc reactor using RuO2 coated on titanium as anode and titanium as cathode. The sodium chloride present in the effluent was used as supporting electrolyte. Operating parameters such as current density, reservoir hold-up and electrolysis time were studied for maximum Chemical Oxygen Demand (COD) reduction and other relevant parameters such as current efficiency and power consumption per kg of COD removal were calculated. The higher flow rate and lower reservoir hold-up resulted in improved COD removal. The applied current density was also found to significantly influence the reduction of COD. A suitable mathematical model is also proposed to illustrate the relationship between the basic parameters. Pseudo mass transfer coefficients were also evaluated for different experimental conditions. Copyright © 2004 Society of Chemical Industry [source] A Comparative Study of Intraplacental Villous Arteries by Latex Cast Model in vitro and Color Doppler Flow Imaging in vivo,JOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 5 2001Junwu Mu Abstract Objective: The purpose of this study was to determine whether color Doppler sonogram can accurately depict the placental vascular structures using a latex cast model of the placental vessels, and to make a nomogram of several blood flow parameters according to the vascular structures. Methods: First, we made 9 latex cast models of placental arteries and performed morphologic observation and measurement. Second, the comparative anatomical observation of placental vessels by color flow mapping was performed for all 9 patients from whom the latex models were made. Third, a total of 102 uncomplicated pregnant women between 18 and 40 weeks gestation were examined by color Doppler imaging. The resistance indices (RI) and peak systolic velocity (PSV) were measured. Results: In the latex cast model of placentas, cotyledons could be differentiated by the presence of independent vascular structure units. First, second, third and fourth branches were noted in one cotyledon. Cotyledons were easily identified and counted by color Doppler imaging. Each cotyledon contained only one first branch of the intraplacental villous artery (IPVA). The number of IPVA-1 on color Doppler imaging was equal to the number of the cotyledon calculated from the latex model. RI exhibited a negative, and PSV a positive correlation with gestational age (p < 0.05 in both cases). At any given gestational age, both RI and PSV in the peripheral arteries were significantly lower (p < 0.01) than those in the upstream arteries. Conclusions: Color Doppler flow sonography is a valuable tool for detecting the blood flow of intraplacental villous arteries in vivo and the images agree with the vascular anatomy of placenta in vitro. These results may also provide the basic parameters for future studies of some complicated pregnancies. [source] Evaluation of hepatotropic targeting properties of allogenic and xenogenic erythrocyte ghosts in normal and liver-injured ratsLIVER INTERNATIONAL, Issue 2 2008Olav A. Gressner Abstract Background/Aims: Haemoglobin-depleted erythrocyte ghosts have been recommended as vesicle carriers of drugs with hepatotropic properties. However, the influence of liver injury on ghost elimination and targeting has not been reported so far. Methods: Human and rat ghosts were prepared and loaded with model substances, and the basic parameters were characterized. Ghosts were injected intravenously into rats with acute, subacute and chronic liver injuries. Elimination from circulation, organ distribution and cellular targeting was measured. The uptake of ghosts by liver macrophages/Kupffer cells was determined in cell culture. Results: Ghosts are strong hepatotropic carriers with a recovery of 90% in normal liver. Kupffer cells are the almost exclusive target cell type. Hepatotropic properties remain in rats with chronic liver diseases, but are reduced by 60,70% in acute liver damage as a result of decline of phagocytosis of macrophages/Kupffer cells. Although the uptake of ghosts per gram liver tissue in chronic liver injury was also reduced by about 40%, the increase of liver mass and of macrophages/Kupffer cells compensated for the reduced phagocytotic activity. In subacute injury, the uptake per gram liver tissue was only moderately reduced. Conclusion: Drug targeting with ghosts might be feasible in chronic and subacute liver injuries, e.g. fibrogenesis and tumours, because the content of ingested ghosts is released by Kupffer cells into the micro-environment, providing the uptake by and pharmacological effects on adjacent cells. [source] The constitution and the politics of national identity in SpainNATIONS AND NATIONALISM, Issue 1 2010ENRIC MARTÍNEZ-HERRERA ABSTRACT. The 1978 Spanish Constitution enshrined the recognition of linguistic, cultural, and some degree of ,national' pluralism in the country and outlined procedural mechanisms for the creation of regional ,autonomies', which has given rise to a de facto asymmetrical federal state. This article begins by analyzing the compromise over issues of national identity embedded in the Constitution and the process by which this was forged. It highlights the articulation among political forces of contending conceptions of national identity and different projects for reorganising the territorial structure within and/or against the Spanish state. It also describes the social bases of support for the respective projects. Next, the article examines recent challenges to the parameters of the constitutional compromise. It shows that citizens' support for the basic parameters of the 1978 compromise remains high and has even become stronger. It emphasises that the preferences of the general public stand in sharp contrast with the preferences of influential sections of the Basque and Catalan regional political establishment, and it concludes that current challenges to the constitutional compromise are driven by political elites. [source] Quantitative research for nonprofit managementNONPROFIT MANAGEMENT & LEADERSHIP, Issue 4 2006Wolfgang Bielefeld Although the literature on organizational management has burgeoned recently, it has focused primarily on for-profit organizations. Moreover, widely published management prescriptions are often faddish in nature. It is risky for nonprofit managers to uncritically adopt these prescriptions. Not only may they be inappropriate for the Nonprofit setting, they may also be based on inadequate research. The nonprofit sector needs to develop its own research agenda and distribute usable findings to nonprofit managers. This process is in its infancy. While research on the nonprofit sector has been vigorous over the last few decades, most of it has focused on philanthropy or the delineation of the sector's dimensions. It is vitally important that management practices in the Nonprofit sector be based on sound, useful research. Given the nature of social science research, much of this will be quantitative research. In this article, I lay out some basic parameters of quantitative research and discuss its relevance to and utility for nonprofit management. [source] Structure of small II-VI semiconductor nanoparticles: A new approach based on powder diffractionPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 9 2007Franziska Niederdraenk Abstract In many cases of nanostructures a better understanding of the optical, electronic, and catalytic properties is hindered by a lack of detailed structural knowledge of sufficient quality. This is in particular true for very small nanoparticles (<5 nm) where quantum confinement effects play a dominant role. We introduce a novel method for the detailed structural analysis of such small nanoparticles, which includes not only the modeling of basic parameters like size, shape, and structure, but also allows to determine impurities and defects (like, e.g., stacking faults), stress and relaxation effects, etc. Distributions of basic parameters as the size distribution are also implemented by enabling ensemble averaging. Different examples obtained from CdS, ZnS and ZnO particles are presented and demonstrate the superiority of the new approach compared to simpler methods. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] A General Empirical Law of Public Budgets: A Comparative AnalysisAMERICAN JOURNAL OF POLITICAL SCIENCE, Issue 4 2009Bryan D. Jones We examine regularities and differences in public budgeting in comparative perspective. Budgets quantify collective political decisions made in response to incoming information, the preferences of decision makers, and the institutions that structure how decisions are made. We first establish that the distribution of budget changes in many Western democracies follows a non-Gaussian distribution, the power function. This implies that budgets are highly incremental, yet occasionally are punctuated by large changes. This pattern holds regardless of the type of political system,parliamentary or presidential,and for level of government. By studying the power function's exponents we find systematic differences for budgetary increases versus decreases (the former are more punctuated) in most systems, and for levels of government (local governments are less punctuated). Finally, we show that differences among countries in the coefficients of the general budget law correspond to differences in formal institutional structures. While the general form of the law is probably dictated by the fundamental operations of human and organizational information processing, differences in the magnitudes of the law's basic parameters are country- and institution-specific. [source] Application of artificial neural networks for the estimation of tumour characteristics in biological tissuesTHE INTERNATIONAL JOURNAL OF MEDICAL ROBOTICS AND COMPUTER ASSISTED SURGERY, Issue 3 2007Seyed Mohsen Hosseini Abstract Background Artificial tactile sensing is a method in which the existence of tumours in biological tissues can be detected and computerized inverse analyses used to produce ,forward results'. Methods Three feed-forward neural networks (FFNN) have been developed for the estimation of tumour characteristics. Each network provides one of the three parameters of the tumour, i.e. diameter, depth and tumour:tissue stiffness ratio. A resilient back-propagation (RP) algorithm with a leave-one-out (LOO) cross-validation approach is used for training purposes. Results The proposed inverse approach based on neural networks is a reliable and efficient tool for diagnostic tests in order to accurately estimate the basic parameters of the tumour in the tissue. Conclusion There is a non-linear correlation between the tumour characteristics and their effects on the extracted features. In general, reliable estimation of tumour stiffness is obtained when the depth of tumour is small. Copyright © 2007 John Wiley & Sons, Ltd. [source] NEW FRAMES OF ARCHAEOMETRICAL DESCRIPTION OF SPINDLE WHORLS: A CASE STUDY OF THE LATE ENEOLITHIC SPINDLE WHORLS FROM THE 1C SITE IN GRÓDEK, DISTRICT OF HRUBIESZÓW, POLANDARCHAEOMETRY, Issue 5 2010T. CHMIELEWSKI The essential role of yarn spinning in textile production is indisputable. In this context, spindle whorls, the basic spinning accessories that can be found in the archaeological record, are commonly discussed. Even though the importance of the technical specification of spindle whorls has been already recognized by some authors, their functional characteristics are usually limited to the basic parameters affecting their usage range (i.e., weight, diameter and height). And since the mass moment of inertia of spindle whorls is considered to be a salient index when discussing their technical variability, the descriptions are deficient. With this short study, we intend to implement further research with more complete and flexible frames for the description of spindle whorls, based on a simple and fast-paced method of the angular mass measurement as well as relevant typology based on clear morphometrical criteria. On the basis of the examination of a small sample of Eneolithic artefacts (the South-Eastern Group of the Funnel Beaker Culture, c. 3650 to 2800 bc), a case study of the functioning of spindle whorls is also conducted. [source] Night-time science with large solar telescopes: The magnetic Sun through timeASTRONOMISCHE NACHRICHTEN, Issue 6 20102Article first published online: 18 JUN 2010, S.C. Marsden Abstract Today the Sun has a regular magnetic cycle driven by a dynamo action. But how did this regular cycle develop? How do basic parameters such as rotation rate, age, and differential rotation affect the generation of magnetic fields? Zeeman Doppler imaging (ZDI) is a technique that uses high-resolution observations in circularly polarised light to map the surface magnetic topology on stars. Utilising the spectropolarimetric capabilities of future large solar telescopes it will be possible to study the evolution and morphology of the magnetic fields on a range of Sun-like stars from solar twins through to rapidly-rotating active young Suns and thus study the solar magnetic dynamo through time. In this article I discuss recent results from ZDI of Sun-like stars and how we can use night-time observations from future solar telescopes to solve unanswered questions about the origin and evolution of the Sun's magnetic dynamo (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] A New Method for Clay Mineral Analysis and Its Application in GeologyACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 4 2002WANG Hejing Abstract, X-ray diffraction (XRD) peaks in a low-angle diffraction section of clay minerals, especially those of authigenic origin, have broadening and tailing features in shape. Using the five basic parameters, peak position, peak height, width, shape coefficient and asymmetry, to describe an XRD peak is more accurate, comprehensive and integrated than using only 3 of them, position, height and width. Following the concept of the five basic parameters of an XRD peak, the program Decoform proposed in this study provides more information in mineralogical analyses by fitting actual XRD profiles. In combination with the HW-IR plot, Decoform can be systematically and accurately used in the comprehensive analyses of crystallinity, domain size, lattice strain and quantitative phase. It is also of value for the geological investigations of diagenesis, metamorphism, basin maturity, structural stress field and so on. [source] | |||||||||||||||||||