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Selected AbstractsNumerical and analytical calculations of the temperature and flow field in the upwind power plantINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 6 2004Henry Pastohr Abstract The upwind power plant is an interesting system to generate electrical power from free solar energy. The authors have carried out an analysis to improve the description of the operation mode and efficiency. The pressure drop at the turbine and the mass flow rate have a decisive influence on the efficiency. This can be determined only by coupling of all parts of an upwind power plant. In this study the parts ground, collector, chimney and turbine are modelled together numerically. The basis for all sections is the numerical CFD programme FLUENT. This programme solves the basic equations of the thermal fluid dynamics. Model development and parameter studies particularly arise with this tool. Additional to the calculations using FLUENT a simple model is developed for comparison purposes and parameter studies. The numerical results with FLUENT compare well with the results given by the simple model, therefore, we can use the simple model for parameter studies. The basis for the geometry is the prototype Manzanares. Copyright © 2004 John Wiley & Sons, Ltd. [source] Several basic and practical aspects related to electrochemical deionization of waterAICHE JOURNAL, Issue 3 2010Yaniv Bouhadana Abstract We examine water desalination processes based on the electrosorption of ions onto activated carbon electrodes (capacitive deionization, CDI). A flow-by operation mode was used (solutions flows within channels in the separator, parallel to the electrodes) in both continuous and stopped flow experiments. The different response of solutions containing more than 5000 ppm NaCl and dilute solutions (e.g., 1000 ppm NaCl) to the applied potential is discussed. The electrical current transients on potential steps were faster by two orders of magnitude than the resulting concentration transients due to the dynamics of these deionization processes and the properties of the cells used herein. Guidelines for the practical development of capacitive water deionization processes are discussed herein. It is assumed that for brackish water containing several thousands ppms of NaCl, CDI may be advantageous over competitive methods (e.g., reverse osmosis). © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Ion motion in the rectangular wave quadrupole field and digital operation mode of a quadrupole ion trap mass spectrometer,RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 1 2006L. Ding A quadrupolar electric field driven by a rectangular wave voltage can be used for mass-selective storage and analysis. The ion motion in such an electric field is derived, and the stability of ions is presented in the a-q diagram that is commonly used for sinusoidal wave quadrupole mass spectrometry in association with the solution of the Mathieu equation. The pseudo-potential well is discussed in an approximation that leads to the relation of secular frequency to operating parameters. A scheme for a digital ion trap mass spectrometer is described, based on this theory. An ion optics simulation was performed to check the theory of resonant ejection, and to prove the feasibility of the mass scan method for a practical ion trap of such geometry. Copyright © 2005 John Wiley & Sons, Ltd. [source] Quality of Life Correlates After Surgery for Laryngeal Carcinoma,,THE LARYNGOSCOPE, Issue 10 2007Julian Bindewald Abstract Objectives: To assess the correlation of operation mode, postoperative radiotherapy, and disease stage factors with the health-related quality of life (HRQL) measures after surgery for laryngeal carcinoma. Study Design: Reanalysis of data of two multi-institutional cross-sectional studies. Patients and Methods: We interviewed 218 laryngectomees and 153 partial laryngectomy patients in and near Leipzig, Germany, in two cross-sectional studies, using the general and the head- and neck-specific quality of life questionnaires of the European Organization for the Research and Treatment of Cancer (EORTC QLQ-C30 and EORTC QLQ-H&N35). Multifactorial univariate and multivariate models were calculated, with laryngectomy vs. partial laryngectomy, radiotherapy (irradiated or not), and disease stage (International Union Against Cancer [UICC] stages I/II vs. III/IV) as influencing factors and the HRQL scales and items as dependent variables. Analyses were adjusted for the patient's age and the time elapsed since the operation. Results: Laryngectomees were more affected in their sense of smell (P , .000). Among irradiated patients, functioning levels and many symptom scales showed worse results (P , .05). Both operation mode and postoperative radiotherapy were independently associated with head- and neck-specific HRQL in multivariate analysis. Differences between disease stage groups, however, were not significant. Patient's age was an influencing factor on HRQL, but time since operation was not. Conclusions: Postoperative radiotherapy seems to have the greatest impact on patients' HRQL independent of other clinical factors following surgery for laryngeal carcinoma. Aftercare of irradiated laryngeal carcinoma patients should focus more on the patient's quality of life. [source] Embryonic systems implementation with FPGA-based artificial cell network hardware architecturesASIAN JOURNAL OF CONTROL, Issue 2 2010Csaba Szász Abstract The cell-based structure, which makes up the majority of biological organisms, offers the ability to grow with fault-tolerance abilities and self-repair. By adapting these mechanisms and capabilities to nature, scientific approaches have promoted research for understanding related phenomena and associated principles to engine complex novel digital systems and improve their capability. Founded by these observations, the paper is focused on computer-aided modeling, simulation and experimental research of embryonic systems, with the purpose to implement very large scale integrated hardware structures which are able to imitate cells or artificial organism operation mode, with similar robustness and fault-tolerance properties like their biological equivalents from nature. Field Programmable Gate Array (FPGA)-based artificial cell model configuration provided with strongly network communication capabilities is proposed and developed. The presented theoretical and simulation approaches were tested on a laboratory prototype embryonic system (embryonic machine), for study and implementation of basic abilities of living organisms. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society [source] Potential of different techniques of preferential crystallization for enantioseparation of racemic compound forming systemsCHIRALITY, Issue 8 2009Daniel Polenske Abstract Recently the feasibility of preferential crystallization for enantioseparation of racemic compound forming systems has been demonstrated (Lorenz et al., Application of preferential crystallization to resolve racemic compounds in a hybrid process. Chirality 2006;18:828,840; Polenske et al., Separation of the propranolol hydrochloride enantiomers by preferential crystallization: thermodynamic basis and experimental verification. Cryst Growth Des 2007;7:1628,1634). Here, the development and the potential of an efficient separation process operated via two different techniques of preferential crystallization are studied: (1) seeded isothermal preferential crystallization and (2) auto-seeded polythermal preferential crystallization. Both techniques were investigated in the batch and in the cyclic operation mode. On the example of mandelic acid as a typical racemic compound forming system, it is demonstrated that a cyclic auto-seeded polythermal process is feasible and significantly more efficient than the seeded isothermal one. Chirality, 2009. © 2008 Wiley-Liss, Inc. [source] Inventory of shipping emissions in Izmit Gulf, TurkeyENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 2 2010Alper Kiliç Abstract Ships are significant emissions sources in transportation sector. The environmental effects of shipping emissions become more serious because of insufficient international rules and inspections. Especially in inland waters, canals, straits, gulfs, and port areas emissions effects on environment and health are more important. Izmit Gulf is the major industrial, transport, and inland water region which is affected from shipping emissions with 37 ports and industrial plants. In this study, NOx, SO2, CO2, HC, and PM emission amounts from 11,645 ships called to Izmit Gulf in 2005. These emissions are classified according to ships operation modes and ship types. Annual shipping emissions are estimated as 5,356 t yr,1 for NOx, 4,305 t yr,1 for SO2, 254,261 t yr,1 for CO2, 232 t yr,1 for HC and 487 t yr,1 for PM. To determine the most probably effected regions in the gulf, the spatial distribution of NOx emissions within the Gulf region has been prepared in 1 × 1 Nm2 (Nautical miles) grid cells based on ship movement data along the various routes. Ships in Izmit Gulf contribute to urban pollution with sulfur dioxide significantly. © 2009 American Institute of Chemical Engineers Environ Prog, 2010 [source] Measurements and numerical simulations for optimization of the combustion process in a utility boilerINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 5 2004A. Vikhansky Abstract A three-dimensional computational fluid dynamics code was used to analyse the performance of 550MW pulverized coal combustion opposite a wall-fired boiler (of IEC) at different operation modes. The main objective of this study was to prove that connecting plant measurements with three-dimensional furnace modelling is a cost-effective method for design, optimization and problem solving in power plant operation. Heat flux results from calculations were compared with measurements in the boiler and showed good agreement. Consequently, the code was used to study hydrodynamic aspects of air,flue gases mixing in the upper part of the boiler. It was demonstrated that effective mixing between flue gases and overfire air is of essential importance for CO reburning. From our complementary experimental-numerical effort, IEC considers a possibility to improve the boiler performance by replacing the existing OFA nozzles by those with higher penetration depth of the air jets, with the aim to ensure proper mixing to achieve better CO reburning. Copyright © 2004 John Wiley & Sons, Ltd. [source] Advances and challenges in super-resolutionINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 2 2004Sina Farsiu Abstract Super-Resolution reconstruction produces one or a set of high-resolution images from a sequence of low-resolution frames. This article reviews a variety of Super-Resolution methods proposed in the last 20 years, and provides some insight into, and a summary of, our recent contributions to the general Super-Resolution problem. In the process, a detailed study of several very important aspects of Super-Resolution, often ignored in the literature, is presented. Specifically, we discuss robustness, treatment of color, and dynamic operation modes. Novel methods for addressing these issues are accompanied by experimental results on simulated and real data. Finally, some future challenges in Super-Resolution are outlined and discussed. © 2004 Wiley Periodicals, Inc. Int J Imaging Syst Technol 14, 47,57, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.20007 [source] A dual continuous- and burst-mode clock recovery module utilizing fiber dispersionMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 8 2010Minhui Yan Abstract A clock recovery module suitable for both burst- and continuous-mode optical receiver utilizing fiber dispersion is experimentally demonstrated for the first time. The module utilizes the nonlinear characteristics of the received nonreturn-to-zero (NRZ) optical signals experiencing the fiber dispersion and the photo-detection to extract the clock information. Experiments demonstrated its functionality in both operation modes up to 9 Gbps. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1747,1750, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25347 [source] The Multi-frequency Robotic facility REM: first resultsASTRONOMISCHE NACHRICHTEN, Issue 6-8 2004S. Covino Abstract The REM Observatory, recently installed and commissioned at la Silla Observatory Chile, is the first moderate aperture robotic telescope able to cover simultaneously the visible-NIR (0.45-2.3 microns) wavelength range. Due to its very fast pointing and its full robotization REM is conceived for fast transients observation. The high throughput Infrared Camera (REMIR) and the Visible imaging spectrograph (ROSS), simultaneously fed by a dichroic, allow to collect high S/N data in an unprecedented large spectral range on a telescope of this size. The REMobservatory is an example of a versatile and agile facility necessary complement to large telescopes in fields in which rapid response and/or target pre-screening are necessary. This paper describes the principal Characteristics and operation modes of the REM observatory and gives on overview of the preliminary results obtained during the commissioning phase. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] A multiparallel bioreactor for the cultivation of mammalian cells in a 3D-ceramic matrixBIOTECHNOLOGY PROGRESS, Issue 2 2010Vicky Goralczyk Abstract For adherently growing cells, cultivation is limited by the provided growth surface. Excellent surface-to-volume ratios are found in highly porous matrices, which have to face the challenge of nutrient supply inside the matrices' caverns. Therefore, perfusion strategies are recommended which often have to deal with the need of developing an encompassing bioreactor periphery. We present a modular bioreactor system based on a porous ceramic matrix that enables the supply of cells with oxygen and nutrients by perfusion. The present version of the reactor system focuses on simple testing of various inoculation and operation modes. Moreover, it can be used to efficiently test different foam structures. Protocols are given to set-up the system together with handling procedures for long-time cultivation of a CHO cell line. Experimental results confirm vital growth of cells inside the matrices' caverns. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] | ||||||||||||||||