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11th International Fluid Power Conference, 11. IFK, Aachen, Germany, 19 Mar 2018 - 21 Mar 2018; Aachen : [Mainz], 14-27 (2018). Published by [Mainz], Aachen

Se obtuvieron correlaciones matemáticas de rendimiento de producción, remoción de cenizas y partición de agua para describir el comportamiento de un hidrociclon "solo agua" (usa solamente agua como medio denso) desde el punto de vista hidráulico y geométrico. Se utilizó un hidrociclón de 254mm de diámetro y un carbón de la mina la Yolanda (Valle del Cauca). La concentración másica de carbón usada fue entre 3.0 y 10.0% (p/p), la longitud del "vortex finder" entre 152.4 y 228.6mm y el diámetro del "apex" entre 19.1 y 44.5mm. A partir de las diferentes pruebas se obtuvieron rendimientos de producción entre 11.9 y 83.2% (p/p) y remociones de cenizas entre 41.8 y 95.2% (p/p). Las ecuaciones matemáticas obtenidas presentaron factores de correlación superiores al 98.7% lo cual predice buena confiabilidad entre los resultados experimentales y los teóricos.

Quantum well solar cells (QWSC) are novel devices with the potential to achieve high efficiency in an alternative approach to tandem or cascade cells. Spectrally tuned quantum well solar cells were designed and fabricated to deliver enhanced performance under the specific spectral resource of Cyprus. Non-destructive techniques such as external quantum efficiency (EQE) and electroluminescence (EL) have been used to characterize the innovative devices and indicate differences in performance between quantum wells with different Indium content and number of wells. For the investigation of carrier injection mechanisms in the cells, examination of the current and temperature dependence of the EL characteristics has been performed. Preliminary results from EL tests displayed multiple peaks in the region of quantum wells whereas reduced radiative recombination was observed at higher temperatures due to thermal escape of carriers via tunnelling. Additionally EQE measurements displayed the effect of quantum wells in the short-circuit current of the cells by indicating redshift of the cut-off wavelength. Finally our initial studies have shown that there is an excellent agreement between the resulting EQE and EL curves. 27th European Photovoltaic Solar Energy Conference and Exhibition; 397-402

The requirements for the contact metal deposited on solar cells are rising as the size of solar cells grows. Particularly, the improvement of the electric properties – especially the conductivity – is attracting interest. Light-induced plating is deemed to be a sophisticated approach to deposit a highly conductive metal layer on an arbitrarily generated seed layer. Although already in industrial operation to some extent, the mechanism is not understood in detail. In addition, the aim of avoidance of cyanide containing electrolytes for silver deposition is high. We will show voltammetric techniques are an appropriate approach investigating these topics. 23rd European Photovoltaic Solar Energy Conference and Exhibition, 1-5 September 2008, Valencia, Spain; 1785-1788

Increasing population growth requires more sustainable development of energy. This non-contaminated energy has an inexhaustible energy source. One of the vital parameters in such structures is the choice of foundation type. Suction caissons are now used extensively worldwide for offshore wind turbine. Considering the presence of a number of offshore wind farms in earthquake areas, the study of the seismic behavior of suction caisson is necessary for better design. In this paper, the results obtained from three suction caisson models with different diameter (D) and skirt length (L) in saturated sand were compared with centrifuge test results. All models are analyzed using 3D finite element (FE) method taking account of elasto-plastic Mohr–Coulomb constitutive model for soil which is available in the ABAQUS library. The earthquake load applied to the base of models with a maximum acceleration of 0.65g. The results showed that numerical method is in relative good agreement with centrifuge results. The settlement and rotation of foundation decrease by increasing the skirt length and foundation diameter. The sand soil outside the caisson is prone to liquefaction due to its low confinement.

This paper describes the application of an Artificial Intelligence (AI) technique to assist in the selection of an Enhanced Oil Recovery method (EOR). The structure of an expert systems selection based on a new formulated screening criteria, Artificial Intelligence selection developed by a computer software called (EKORA), with an easily and friendly user interface by using visual Basic-6 environment tools is presented. An additional capability provided by this software is the ability of changing and editing the parameters of EOR methods which emerged or tested in current implementation projects. Other commercial expert systems either offer limited or no capabilities for changing and editing the EOR parameters of screening rule.

the aim of optimization comes in to play in each and every field of engineering application. Thus such approach to make out to select correct method to adopt optimization would be great. The simulated annealing approach for simulation is taken to be basic to take out the and optimization can be done to genetic algorithm approach with convenient way https://journalnx.com/journal-article/20150605

Cryptographic primitives with low-latency performance have gained momentum lately due to an increased demand for real-time applications. Block ciphers such as PRINCE enable data encryption (resp. decryption) within a single clock cycle at a moderately high operating frequency when implemented in a fully-unrolled fashion. Unsurprisingly, many typical environments for unrolled ciphers require protection against physical adversaries as well. Yet, recent works suggest that most common SCA countermeasures are hard to apply to low-latency circuits. Hardware masking, for example, requires register stages to offer resistance, thus adding delay and defeating the purpose of unrolling. On another note, it has been indicated that unrolled primitives without any additional means of protection offer an intrinsic resistance to SCA attacks due to their parallelism, asynchronicity and speed of execution. In this work, we take a closer look at the physical security properties provided by unrolled cryptographic IC implementations. We are able to confirm that the nature of unrolling indeed bears the potential to decrease the susceptibility of cipher implementations significantly when reset methods are applied. With respect to certain adversarial models, e.g., ciphertext-only access, an amazingly high level of protection can be achieved. While this seems to be a great result for cryptographic hardware engineers, there is an attack vector hidden in plain sight which still threatens the security of unrolled implementations remarkably – namely the static power consumption of CMOS-based circuits. We point out that essentially all reasons which make it hard to extract meaningful information from the dynamic behavior of unrolled primitives are not an issue when exploiting the static currents for key recovery. Our evaluation is based on real-silicon measurements of an unrolled PRINCE core in a custom 40nm ASIC. The presented results serve as a neat educational case study to demonstrate the broad differences between dynamic and static power information leakage in the light of technological advancement. IACR Transactions on Cryptographic Hardware and Embedded Systems, Volume 2020, Issue 4