Techno‐economic analysis of FiWi access networks based on optimized source packet traffic

Fiber wireless access networks (FiWi) are capable of providing broadband 100 Mbit/s services with acceptable costs and can be considered as a competitive alternative to fiber to the home (FTTH). Techno‐economic analysis of viable FiWi architectures is needed in order to obtain the most suitable solution taking into account both technical and economical viewpoints. In this paper, a new approach to techno‐economic analysis of the FiWi networks is proposed. The proposed approach is based on the net present value calculation with the source packet traffic generation rate and traffic intensity as input parameters. As a precondition to net present value calculation, a traffic optimization procedure that assures the quality of experience is performed. Case study results indicate the usability of the proposed method.     

Vector control system of a self-excited induction generator including iron losses and magnetic saturation

We propose a novel indirect rotor-flux-oriented control system of a self-excited induction generator with online calculated iron losses and magnetic saturation. Within the control system, the iron loss resistance is represented as a function of both the synchronous frequency and magnetizing flux, and the magnetizing inductance is represented as a function of the magnetizing current. Both iron losses and saturation characteristics were determined from no-load tests. The effectiveness of the proposed approach is verified through both simulations and experiments. Through a comparison with the conventional approach, insight is provided into the efficiency estimation error and detuning due to iron losses.     

Scale matters: A Spatiotemporal Analysis of Freshwater Conflicts from 1900-2019

Water Resources Management - The threat of conflicts over water resources has become a serious issue in both academic and policy circles. While recent scholarship points to an increasing incidence...     

Hypoproteinemia as a prognostic risk factor for arteriovenous fistula failure

Introduction: Any vascular access is of limited duration with many factors which influence survival in patients on chronic hemodialysis (HD). Hypoproteinemia as a marker of chronic illness is common among chronic HD patients. Our aim was to analyze the survival of the primary arteriovenous fistula (AVFs) and the risk factors which influence their patency and to test the hypothesis that patients with normal values of serum proteins have lower risk of AVF failure compared to patients with hypoproteinemia. Methods: Seven hundred thirty‐four consecutive patients were included who underwent creation of an AVF. The patients were prospectively followed‐up for 2 years. Only patients with AVF function after a month from its creation were analyzed. The patients were divided into two subgroups, with normal and low serum protein levels (<65 g/L). Findings: At follow‐up 497 (67.7%) AVFs were still functional while 237 (32.3%) AVFs failed due to thrombosis or stenosis. Serum proteins and AVFs created on the forearm were positive predictors while diabetes was a negative predictor of longer AVF survival (P < 0.001; P = 0.003; P = 0.043). When comparing patients with normal and low serum protein levels (<65 g/L), mean survival time was significantly longer in patients with normal serum levels (P < 0.001). Discussion: In this study, hypoproteinemia was an independent prognostic marker for AVF failure at 2 years. Hypoproteinemia, based on our results, is an independent, more sensitive and prognostic marker of possible vascular access failure than the presence of other common factors which influence shorter AVF survival.     

The Charité Grid Portal: User-friendly and Secure Access to Grid-based Resources and Services

The Charité Grid Portal combines portal components from different groups and projects to provide domain researchers a gateway to Grid-based biomedical applications. Trusted users can securely access and employ Grid resources and services. In this paper, five portal components are presented: (1) The credential management administrates the user-credentials and authenticates them to the Grid. (2) The brain imaging data analysis (FSL) submits workflows to the Grid as part of Medical Image processing. (3) The integrated web services of Generic Workflow Execution Service (GWES) manage workflows executed by users in the Grid. (4) The data management component provides secure and efficient data management in a Grid environment, and enables high-speed data transports between user and Grid. (5) The lung sound analysis application provides twofold-pseudonymization before data-transferred to the Grid. The implementation as standardized portlets allows easy integration of specific components into different Grid portals such as the VO specific MediGRID and PneumoGrid portals.     

Evaluation of atrazine degradation in UV/FeZSM-5/H2O2 system using factorial experimental design

Degradation of atrazine in model wastewater by UV/FeZSM-5/H₂O₂ system chosen as optimal for application of advanced oxidation process (AOP) has been studied in a batch photo reactor. The statistical study of the process was performed using two-level full factorial experimental design with the three process parameters. Individual parameters and their interaction effects on atrazine degradation were determined and statistical model of process was developed. The optimal operating conditions were established. This approach has also given a broader insight of the processes that were occurring in the reaction system, and it has finally led to simplification in terms of kinetics. Atrazine degradation was described by pseudo-first-order kinetics with observed rate constant k′ = 2 × 10⁻³ s⁻¹.     

Effect of rapid solidification and alloying addition on lattice distortion and atomic ordering in L10 tial alloys and their ternary alloys

Binary and ternary L1₀ type titanium alloys were rapidly quenched into thin foils by the hammer-anvil quenching technique. The nominal alloy compositions include Ti_1-xAl_x and (Ti_1-xAl_x)_{100-@#@ y}M_y, wherex = 0.5 to 0.6; y= 1 to 4; and M is V, Cr, Mn, Fe, Co, Ni, and Ge. Lattice parameters of Ll₀ phases in these alloys were studied by X-ray diffractometer using the foils and their powders. Simultaneously, long-range order parameters of these Ll₀ phases in the as-quenched foils and the annealed powders were determined from the superlattice intensity measured by X-ray diffractometer. Rapid quenching suppresses long-range ordering (S) during solidification and, thereby, reduces lattice distortion (c/a) in Ll₀ titanium alloys. A small amount of alloying element has a large effect on thec/a ratio. The atomic size effect and probably substitutional site preference play an important role in such ac/a reduction. From the density measurement, it is found that antisite defects are a predominant mode in Al-rich off-stoichiometric TiAl compound alloys. Determined long-range order value is significantly low in as-quenched binary TiAl due to rapid quenching, and the highest ordering occurs at as-quenched Ti₄₅Al₅₅ alloy. The relationship betweenc/a andS in Ll₀ Ti₄₅Al₅₅ may be written asc/a = 1 + 0.025 ·S.     

Protein Adsorption on Hydroxyapatite Nanosensors with Different Crystal Sizes Studied In Situ by a Quartz Crystal Microbalance with the Dissipation Method

Hydroxyapatite (HAp) nanocrystals with different crystal sizes were deposited by the electrophoretic deposition method on the gold surface of a quartz crystal microbalance with a dissipation probe. The nanosensors formed this way were used to elucidate the adsorption mechanism of proteins with a similar pI value. The crystal sizes and the area of the a -plane affected only the adsorption amount of human serum albumin, but not that of bovine plasma fibrinogen. The viscoelastic property, Δ D/ Δ f , of each absorbed layer on the nanosensors was almost constant. The protein adsorption mechanism can be explained as follows: the dissociated carboxyl groups (negative charge) of albumin were interacted with calcium ions and the hydrated amine groups (positive charge) at the αC domain of fibrinogen were with phosphate ions on the HAp surface.     

Decolourization and mineralization of commercial reactive dyes by using homogeneous and heterogeneous Fenton and UV/Fenton processes

The oxidative decolourization and mineralization of three reactive dyes in separately prepared aqueous solutions C.I. Reactive Yellow 3 (RY3), C.I. Reactive Blue 2 (RB2) and C.I. Reactive Violet 2 (RV2) by using homogeneous and heterogeneous Fenton and UV/Fenton processes have been investigated. The effects of H(2)O(2), Fe(2+) and Fe(0) concentrations, Fe(2+)/H(2)O(2) and Fe(0)/H(2)O(2) molar ratios at pH 3 and T=23+/-1 degrees C have been studied. Optimal operational conditions for the efficient degradation of all three dye solutions (100 mg L(-1)) were found to be Fe(2+)/H(2)O(2)=0.5mM/20mM and Fe(0)/H(2)O(2)=2mM/1mM. The experimental results showed that the homogeneous Fenton process employing UV irradiation was the most effective. By using this process, the high levels of mineralization (78-84%) and decolourization (95-100%) were achieved. Pseudo-first-order degradation rate constants were obtained from the batch experimental data.     

Predictive model for municipal waste generation using artificial neural networks—Case study City of Zagreb,Croatia

The European Union's environmental legislation related to environmental protection, already implemented in the national legislation of the Republic of Croatia, aims to introduce a system of integrated and sustainable waste management. Within such a system, it is of utmost importance to have a better estimate of the amount of municipal waste generated, which directly influences future planning in the waste management sector. The aim of this research was to develop and optimize models for the estimation of generated municipal waste by application of methodology using neural network models, and taking into account the socio‐economic impact as well as the inputs regarding the actual waste management trends. In this paper, an artificial neural network models were used to predict the municipal waste generation in Zagreb, Croatia. The standardized socio‐economic and waste management variables were chosen to encompass 2013 to 2016 period. Moreover, the test prediction of the observed data was performed for 2017. Developed models sufficiently predicted the quantities of different municipal waste fractions and in that sense can contribute to better planning of upcoming waste management systems that will be sustainable and in order to meet the European Union commitments.