18 research outputs found
Interaction of ocean wave energy converters
No full textIt is expected that several identical Point Absorber Wave Energy Converters (PAWECs) will be arranged in arrays to form a Wave Energy Farm. One of the key challenges in designing such a WEC array is their spatial configuration, as the WECs in the farm interact hydrodynamically with each other. This study focuses on different potential PAWEC deployments to identify the best relative position in order to maximise energy output. This is done by resolving the hydrodynamic interactions between a modelled WEC point absorber, with use of open-source Boundary Element Methods (BEM) and time domain WEC simulator. The results from the numerical model are also compared with wave tank testing, to verifythe accuracy of the analysis. The simulations show that the relative position can significantly increase a WEC’s individual power output. A spatial pattern of relative positions that result in higher potential power extraction was shown, with increases up to 20% compared to a single WEC on its own. However, the computational results showed realistic results for only a select number of configurations. As for the experiment, unexpected variations in test conditions occurred, inhibiting the possibility to isolate certain events. Therefore, when cross checking results from both simulations and experiments, the identified simulated trends only partially showed adherence with the experimental data. Henceforth, the knowledge gathered from the simulations can’t conclusively be validated by the experiments conducted in this study. This study shows that the spatial configuration of two WECs influences their individual power outputs.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Transport Engineering and Logistic
Zeta Omega, 1967-1968 Members
No full textZeta Omega was a club at Jacksonville State University. Shown are the 1967-1968 members standing outside in front of the Jacksonville State University stone sign. Bottom row are Dupree, Dant, Davis, Martin, Carrol, Caswell, Pate, Bodden, Crandel, Allen, Marcus, and Glover Jr. In the second row are Willis, Adams, White, Murphy, Bain, Downing, Bruis, Chiarella, and Daily. In the third row are Rogers, McCargo, Reed, Burch, Reaves, Mills, Rhine, Harbin, and Howell.https://digitalcommons.jsu.edu/lib-ac-histimg/15692/thumbnail.jp
Enfermedad trombótica venosa del aparato digestivo. Trombofilia y otros factores de riesgo asociados.
No full textLas enfermedades vasculares digestivas, como son el síndrome de Budd-Chiari, la trombosis portal y del eje esplenoportal, presentan una baja prevalencia pero con una alta morbimortalidad. Es importante investigar el factor de protrombótico por sus implicaciones terapéuticas y porque se pueden encontrar hasta 30% de casos en los que no se idenfiquen factores. Objetivos: Determinar la importancia y la prevalencia de la trombofilia y de otros factores de riesgo implicados en el desarrollo de trombosis esplácnica. Material y método: Estudio observacional, retrospectivo de una serie de casos obtenidos del registro del HCU Lozano Blesa con pacientes bajo tratamiento anticoagulante oral debido a trombosis venosa esplácnica en el período 01/01/2000- 30/06/2016. Resultados: La mayoría de las trombosis esplácnicas se presentaron en hombres con una edad media de 58 años, siendo la localización más frecuente la vena porta y el eje esplenoportal. Se encontraron factores de riesgo de trombosis en el 86,3% de los pacientes, siendo el más frecuente la cirrosis (44,4%), seguido de cirugía intraabdominal (23,3%) destacando el trasplante hepático y por cáncer (16.4%), sobre todo hepatocarcinoma. Se detecta trombofilia plasmática positiva en el 11,3% y trombofilia genética en el 56,5%, siendo la mutación más frecuente la MTHFR C677T (34,7%). Analizando también la mutación de JAK2, en los SMPC fue positiva en el 85,7% de los casos, con mayor prevalencia en la Trombocitemia esencial. Conclusiones: Aunque no se ha encontrado relación estadísticamente significativa entre las trombosis y los distintos factores de riesgo tanto trombofílicos como no trombofílicos, hemos detectado Trombofilia hereditaria en un 59.4 % y como factor único un 17% de los casos; la prevalencia de un solo factor no trombofilico fue del 50.7%. Encontramos un porcentaje bajo de trombosis esplácnica (13.7%) de origen idiopático. Se considera necesario continuar investigando en Trombofilia y otros estudios genéticos como mutación JAK2 con un mayor número de pacientes. Bibliografía: Osaki T, Ichinose A. Current views of activating and regulatory mechanisms of blood coagulation. Nippon Rinsho. 2014;72(7):1206-1211. European Association for the Study of the Liver. Guía de práctica clínica de la EASL: Enfermedades vasculares hepáticas. Journal of Hepatology. 2016; 64:179–202. Zeeshan A. Wani, Riyaz A. Bhat, Ajeet S. Bhadoria, Rakhi Maiwall. Extrahepatic Portal Vein Obstruction and Portal Vein Thrombosis in Special Situations: Need for a New Classification Saudi J Gastroenterol. 2015 May-Jun; 21(3): 129–138. Pasta L,Pasta F,D’Amico M. PAI-1 4G-4G, MTHFR 677TT, V Leiden 506Q, and Prothrombin 20210A in Splanchnic Vein Thrombosis: Analysis of Individual Patient Data From Three Prospective Studies. J CLIN EXP HEPATOL. 2016;6:10–14.Fernández Capitán MC. Trombosis esplácnica. A propósito de RIETE. HEMATOLOGÍA XXIII Congreso Argentino de Hematología.2017;21:117-119. Manzano MC, Barranco B, Uribe M, Mendez N. Portal vein thrombosis: What is new?. Annals of Hepatology. 2015;14(1):20-27. Sigler L, Gutiérrez R, Mendieta M, Sánchez C, Lizola RI, Uribe G. Isquemia mesentérica. Estrategia actual. Rev Mex Angiol. 2015 Jan; 43(1): 14-23. Nery F, Chevret S, Condat B, De RE, Boudaoud L, Rautou PE, et al. Causes and consequences of portal vein thrombosis in 1,243 patients with cirrhosis: results of a longitudinal study. Hepatology 2015;61:660-667. Ageno W. Managing unusual presentations of venous thromboembolism. J Thromb Thrombolysis.2015;39(3):304-310. Ageno W, Riva N, Schulman S et al. Long-term Clinical Outcomes of Splanchnic Vein Thrombosis Results of an International Registry. JAMA Intern Med. 2015;175(9):1474-1480. 70.Yogesh K. Chawla, Vijay Bodh. Portal vein thrombosis. J CLIN EXP HEPATOL 2015;5:22–40. Pérez S, Nofuentes C, García A, Luri P, Morales M, García S. Pileflebitis: una extraña pero posible complicación de las infecciones intraabdominales. Cirugía y Cirujanos. 2015; 83(6):501-505. Gallego Plazas J.Cáncer de hígado. 2015. Saugel B, Lee M, Feichtinger S, Hapfelmeier A, Schmid RM, Siveke JT. Thrombophilic factor analysis in cirrhotic patients with portal vein thrombosis. J Thromb Thrombolysis. 2015;40:54–60. Sawant P, Vashishtha C, Nasa M, Parikh P, Patel J, Agasti A.Thrombophilia Profile in Budd-Chiari Syndrome and Splanchnic Vein Thrombosis: A Study from Western India. J Assoc Physicians India. 2015 Sep;63(9):32-5. Ventura P, Venturelli G, Marcacci M, Fiorini M, Marchini S, Cuoghi C, Pietrangelo A.Hyperhomocysteinemia and MTHFR C677T polymorphism in patients with portal vein thrombosis complicating liver cirrosis. Thromb Res. 2016 May;141:189-95.<br /
Built-In Self-Test Methodology for A/D Converters
No full textA (partial) Built-in Self-Test (BIST) methodology is proposed for analog to digital (A/D) converters. In this methodology the number of bits of the A/D converter that needs to be monitored externally in a test is reduced. This reduction depends, among other things, on the frequency of the applied test signal. At low test signal frequencies only the least significant bit (LSB) needs to be monitored and a "full" BIST becomes feasible. An analysis is made of the trade-off between the size of the on-chip test circuitry and the accuracy of this BIST techniqu
The Twente LINX backplane
No full text. The design of a control system is not finished with the derivation of the necessary control algorithms. When the controller is implemented in a digital computer the system designer has to schedule all control and calculation tasks within the sampling interval of the system. Higher sampling frequencies often improve the system performance. On the other hand, more sophisticated control algorithms require more computing time thus reducing the obtainable sampling frequencies. Therefore, it is important to minimise the overhead of sampling and communication. This paper describes a transputer--based I/O system fulfilling this requirement and shows how the sampling with this system is done. Keywords. Link Based Backplane, Transputer Based I/O, Sampling, Parallel processing, Real-time Computer Systems, Control Engineering, Applications of Computers, Robot control, Transputers, Occam. 1. Introduction At the Control Laboratory of the Electrical Engineering Department of the University of Twe..
Real-time stepper motor control, a hands-on experience in parallel design and implementation of real-time control system
No full textImplementation of KRoC on Analog Devices' "SHARC" DSP
No full textThis paper summarises the experiences gained at the Control Laboratory of the University of Twente in porting the Kent Retargetable occam Compiler -KroC -to the Analog Devices' ADSP21060 SHARC Digital Signal Processor. The choice of porting the KRoC to the DSP processor was in our view both a challenge and an absolute necessity because DSP processors are an important ingredient in modern day control systems. Currently, our implementation contains the most important occam primitives such as channel communication, PAR, ALT, and most of the integer arithmatic. Furthermore, a basic kernel was realised, providing channel-communication based scheduling only. This porting process, using quite straight-forward modifications of the SPARC KRoC-translator, was done within six weeks. A representative benchmark was constructed, showing that the 33Mhz SHARC-KRoC implementation is 40% faster than the the 25Mhz T800 using the INMOS D7205 Toolset
