bluuebunny/crossref_metadata_2025 huggingface dataset:
Vehicle Accident Databases: Correctness Checks for Accident Kinematic Data
Authors: Vangi Dario , Cialdai Carlo , Gulino Michelangelo-Santo , Robbersmyr Kjell Gunnar
Published: January 2018

(1) Background: Data collection procedures allow to obtain harmonization of in-depth road accident databases. Plausibility of calculable accident-related kinematic parameters depends on the constraints imposed on calculation, making their uncertainty degree higher than the one for measurable parameters (i.e., traces, airbag activation, etc.). Uncertainty translates in information loss, making the statistics based on databases analysis less consistent. Since kinematic parameters describe the global accident dynamics, their correctness assessment has a fundamental importance; (2) Methods: the paper takes as reference data collected in the Initiative for the GLobal harmonisation of Accident Data (IGLAD) database for vehicle-to-vehicle crashes. The procedure, however, has general nature and applies identically for other databases and multiple impacts between vehicles. To highlight issues which can arise in accident-related data collection, 3 different checks are proposed for parameters correctness assessment; (3) Results: by 4 examples, 1 with correct and 3 with incorrect parameters reported, the paper demonstrates that errors can go beyond simple calculation uncertainty, implying that a deeper analysis is desirable in data collection; (4) Conclusions: the step-by-step guidelines described in this paper will help in increasing goodness of collected data, providing for a methodology which can be used by each individual involved in accident data collection, both for collection itself and subsequent verification analysis.
Is Natural Language a Perigraphic Process? The Theorem about Facts and Words Revisited
Authors: Dębowski Łukasz
Published: January 2018

As we discuss, a stationary stochastic process is nonergodic when a random persistent topic can be detected in the infinite random text sampled from the process, whereas we call the process strongly nonergodic when an infinite sequence of independent random bits, called probabilistic facts, is needed to describe this topic completely. Replacing probabilistic facts with an algorithmically random sequence of bits, called algorithmic facts, we adapt this property back to ergodic processes. Subsequently, we call a process perigraphic if the number of algorithmic facts which can be inferred from a finite text sampled from the process grows like a power of the text length. We present a simple example of such a process. Moreover, we demonstrate an assertion which we call the theorem about facts and words. This proposition states that the number of probabilistic or algorithmic facts which can be inferred from a text drawn from a process must be roughly smaller than the number of distinct word-like strings detected in this text by means of the Prediction by Partial Matching (PPM) compression algorithm. We also observe that the number of the word-like strings for a sample of plays by Shakespeare follows an empirical stepwise power law, in a stark contrast to Markov processes. Hence, we suppose that natural language considered as a process is not only non-Markov but also perigraphic.
A New Chaotic System with a Self-Excited Attractor: Entropy Measurement, Signal Encryption, and Parameter Estimation
Authors: Xu Guanghui , Shekofteh Yasser , Akgül Akif , Li Chunbiao , Panahi Shirin
Published: January 2018

In this paper, we introduce a new chaotic system that is used for an engineering application of the signal encryption. It has some interesting features, and its successful implementation and manufacturing were performed via a real circuit as a random number generator. In addition, we provide a parameter estimation method to extract chaotic model parameters from the real data of the chaotic circuit. The parameter estimation method is based on the attractor distribution modeling in the state space, which is compatible with the chaotic system characteristics. Here, a Gaussian mixture model (GMM) is used as a main part of cost function computations in the parameter estimation method. To optimize the cost function, we also apply two recent efficient optimization methods: WOA (Whale Optimization Algorithm), and MVO (Multi-Verse Optimizer) algorithms. The results show the success of the parameter estimation procedure.
Calculation of the Connected Dominating Set Considering Vertex Importance Metrics
Authors: Vazquez-Araujo Francisco , Dapena Adriana , Souto-Salorio María , Castro Paula
Published: January 2018

The computation of a set constituted by few vertices to define a virtual backbone supporting information interchange is a problem that arises in many areas when analysing networks of different natures, like wireless, brain, or social networks. Recent papers propose obtaining such a set of vertices by computing the connected dominating set (CDS) of a graph. In recent works, the CDS has been obtained by considering that all vertices exhibit similar characteristics. However, that assumption is not valid for complex networks in which their vertices can play different roles. Therefore, we propose finding the CDS by taking into account several metrics which measure the importance of each network vertex e.g., error probability, entropy, or entropy variation (EV).
Traffic Offloading in Unlicensed Spectrum for 5G Cellular Network: A Two-Layer Game Approach
Authors: Li Yan , Xu Shaoyi
Published: January 2018

Licensed Assisted Access (LAA) is considered one of the latest groundbreaking innovations to provide high performance in future 5G. Coexistence schemes such as Listen Before Talk (LBT) and Carrier Sensing and Adaptive Transmission (CSAT) have been proven to be good methods to share spectrums, and they are WiFi friendly. In this paper, a modified LBT-based CSAT scheme is proposed which can effectively reduce the collision at the moment when Long Term Evolution (LTE) starts to transmit data in CSAT mode. To make full use of the valuable spectrum resources, the throughput of both LAA and WiFi systems should be improved. Thus, a two-layer Coalition-Auction Game-based Transaction (CAGT) mechanism is proposed in this paper to optimize the performance of the two systems. In the first layer, a coalition among Access Points (APs) is built to balance the WiFi stations and maximize the WiFi throughput. The main idea of the devised coalition forming is to merge the light-loaded APs with heavy-loaded APs into a coalition; consequently, the data of the overloaded APs can be offloaded to the light-loaded APs. Next, an auction game between the LAA and WiFi systems is used to gain a win–win strategy, in which, LAA Base Station (BS) is the auctioneer and AP coalitions are bidders. Thus, the throughput of both systems are improved. Simulation results demonstrate that the proposed scheme in this paper can improve the performance of both two systems effectively.
Comparative Evaluation of Integrated Waste Heat Utilization Systems for Coal-Fired Power Plants Based on In-Depth Boiler-Turbine Integration and Organic Rankine Cycle
Authors: Huang Shengwei , Li Chengzhou , Tan Tianyu , Fu Peng , Wang Ligang , Yang Yongping
Published: January 2018

To maximize the system-level heat integration, three retrofit concepts of waste heat recovery via organic Rankine cycle (ORC), in-depth boiler-turbine integration, and coupling of both are proposed, analyzed and comprehensively compared in terms of thermodynamic and economic performances. For thermodynamic analysis, exergy analysis is employed with grand composite curves illustrated to identify how the systems are fundamentally and quantitatively improved, and to highlight key processes for system improvement. For economic analysis, annual revenue and investment payback period are calculated based on the estimation of capital investment of each component to identify the economic feasibility and competitiveness of each retrofit concept proposed. The results show that the in-depth boiler-turbine integration achieves a better temperature match of heat flows involved for different fluids and multi-stage air preheating, thus a significant improvement of power output (23.99 MW), which is much larger than that of the system with only ORC (6.49 MW). This is mainly due to the limitation of the ultra-low temperature (from 135 to 75 °C) heat available from the flue gas for ORC. The thermodynamic improvement is mostly contributed by the reduction of exergy destruction within the boiler subsystem, which is eventually converted to mechanical power; while the exergy destruction within the turbine system is almost not changed for the three concepts. The selection of ORC working fluids is performed to maximize the power output. Due to the low-grade heat source, the cycle with R11 offers the largest additional net power generation but is not significantly better than the other preselected working fluids. Economically, the in-depth boiler-turbine integration is the most economic completive solution with a payback period of only 0.78 year. The ORC concept is less attractive for a sole application due to a long payback time (2.26 years). However, by coupling both concepts, a net power output of 26.51 MW and a payback time of almost one year are achieved, which may promote the large-scale production and deployment of ORC with a cost reduction and competitiveness enhancement.
Strong- and Weak-Universal Critical Behaviour of a Mixed-Spin Ising Model with Triplet Interactions on the Union Jack (Centered Square) Lattice
Authors: Strečka Jozef
Published: January 2018

The mixed spin-1/2 and spin-S Ising model on the Union Jack (centered square) lattice with four different three-spin (triplet) interactions and the uniaxial single-ion anisotropy is exactly solved by establishing a rigorous mapping equivalence with the corresponding zero-field (symmetric) eight-vertex model on a dual square lattice. A rigorous proof of the aforementioned exact mapping equivalence is provided by two independent approaches exploiting either a graph-theoretical or spin representation of the zero-field eight-vertex model. An influence of the interaction anisotropy as well as the uniaxial single-ion anisotropy on phase transitions and critical phenomena is examined in particular. It is shown that the considered model exhibits a strong-universal critical behaviour with constant critical exponents when considering the isotropic model with four equal triplet interactions or the anisotropic model with one triplet interaction differing from the other three. The anisotropic models with two different triplet interactions, which are pairwise equal to each other, contrarily exhibit a weak-universal critical behaviour with critical exponents continuously varying with a relative strength of the triplet interactions as well as the uniaxial single-ion anisotropy. It is evidenced that the variations of critical exponents of the mixed-spin Ising models with the integer-valued spins S differ basically from their counterparts with the half-odd-integer spins S.
Distance Learning and Assistance Using Smart Glasses
Authors: Spitzer Michael , Nanic Ibrahim , Ebner Martin
Published: January 2018

With the everyday growth of technology, new possibilities arise to support activities of everyday life. In education and training, more and more digital learning materials are emerging, but there is still room for improvement. This research study describes the implementation of a smart glasses app and infrastructure to support distance learning with WebRTC. The instructor is connected to the learner by a video streaming session and gets the live video stream from the learner’s smart glasses from the learner’s point of view. Additionally, the instructor can draw on the video to add context-aware information. The drawings are immediately sent to the learner to support him to solve a task. The prototype has been qualitatively evaluated by a test user who performed a fine-motor-skills task and a maintenance task under assistance of the remote instructor.
Extended Kalman Filter Based Sliding Mode Control of Parallel-Connected Two Five-Phase PMSM Drive System
Authors: Kamel Tounsi , Abdelkader Djahbar , Said Barkat , Padmanaban Sanjeevikumar , Iqbal Atif
Published: January 2018

This paper presents sliding mode control of sensor-less parallel-connected two five-phase permanent magnet synchronous machines (PMSMs) fed by a single five-leg inverter. For both machines, the rotor speeds and rotor positions as well as load torques are estimated by using Extended Kalman Filter (EKF) scheme. Fully decoupled control of both machines is possible via an appropriate phase transposition while connecting the stator windings parallel and employing proposed speed sensor-less method. In the resulting parallel-connected two-machine drive, the independent control of each machine in the group is achieved by controlling the stator currents and speed of each machine under vector control consideration. The effectiveness of the proposed Extended Kalman Filter in conjunction with the sliding mode control is confirmed through application of different load torques for wide speed range operation. Comparison between sliding mode control and PI control of the proposed two-motor drive is provided. The speed response shows a short rise time, an overshoot during reverse operation and settling times is 0.075 s when PI control is used. The speed response obtained by SMC is without overshoot and follows its reference and settling time is 0.028 s. Simulation results confirm that, in transient periods, sliding mode controller remarkably outperforms its counterpart PI controller.
Analysis of the Effect of Vehicle, Driving and Road Parameters on the Transient Performance and Emissions of a Turbocharged Truck
Authors: Giakoumis Evangelos , Triantafillou George
Published: January 2018

In this paper, a fundamental analysis of the effects of various influential parameters on the performance and emissions of a turbocharged truck operating under transient conditions is presented. The results derive from a detailed vehicle model that comprises two parts. The first is an engine performance and emissions module that follows a mapping approach, with experimentally derived correction coefficients employed to account for transient discrepancies; this is then coupled to a comprehensive vehicle model that takes into account various vehicle operation attributes such as gearbox, tires, tire slip, etc. Soot, as well as nitrogen monoxide, are the examined engine-out pollutants, together with fuel consumption and carbon dioxide. The parameters examined are vehicular (mass and gearbox), driving (driver ‘aggressiveness’ and gear-shift profile) and road (type and grade). From the range of values investigated, the most critical parameters for the emission of NO and soot are vehicle mass, driving ‘aggressiveness’ and the exact gear-change profile. Vehicle mass, driving ‘aggressiveness’ and road-grade were identified as the most influential parameters for the emission of CO2. A notable statistical correlation was established between pollutant emissions (NO, soot) and vehicle mass or road-tire friction, as well as between fueling/CO2 and vehicle mass, road-tire friction and road grade. It is believed that the results obtained shed light into the effect of critical operating parameters on the engine-out emissions of a truck/bus, underlining at the same time the peculiarities of transient operating conditions.
Generalized Dynamical Modeling of Multiple Photovoltaic Units in a Grid-Connected System for Analyzing Dynamic Interactions
Authors: Orchi Tahsin , Mahmud Md , Oo Amanullah
Published: January 2018

This paper aims to develop the generalized dynamical model of multiple photovoltaic (PV) units connected to the grid along with the dynamic interaction analysis among different PV units. The dynamical models of multiple PV units are developed by considering three different configurations through which these PV units are connected to the grid. These configurations include: (a) the direct connection of multiple PV units to the grid; (b) the connection of multiple PV units to the grid through a point of common coupling (PCC); and (c) the connection of PV units without a PCC. The proposed modeling framework provides meaningful insights for analyzing dynamic interaction analysis where these interactions from other PV units are expressed in terms of voltages and line impedances rather than the dynamics of currents. The dynamic interactions among different PV units for all these configurations are analyzed using both analytical and simulation studies. Simulations are carried out on an IEEE 15-bus test system and dynamic interactions are analyzed from the total harmonic distortions (THDs) in the current responses of different PV units. Both analytical and simulation studies clearly indicate that the effects of dynamic interactions are prominent with the increase in PV units.
Numerical Study of the Effect of Winglets on the Performance of a Straight Blade Darrieus Water Turbine
Authors: Laín Santiago , Taborda Manuel , López Omar
Published: January 2018

This study deals with the three-dimensional unsteady numerical simulation of the flow around a cross-flow vertical-axis water turbine (CFWT) of the Darrieus type. The influence of turbine design on its hydrodynamic characteristics and performance is investigated by means of a time-accurate Reynolds Averaged Navier Stokes (RANS) commercial solver. The flow unsteadiness is described using a transient rotor-stator model in connection with a sliding interface. A classical Darrieus straight blade turbine, based on the NACA0025 airfoil, has been modified adding winglets (symmetric and asymmetric designs) to the blades’ tips with the objective of reducing the strength of the detached trailing vortices. The turbulent features of the flow have been modelled by using different turbulence models (k-ε Renormalization Group, standard Shear Stress Transport, transition Shear Stress Transport and Reynolds Stress Model). As a result, the predicted hydrodynamic performance of the turbine including winglets increases, independently of the employed turbulence model, being the improvement higher when a symmetric winglet design is considered. Moreover, visualization of skin friction lines pattern and their connection with vorticity isosurfaces, illustrating the flow detachment in the three blade configurations, has been carried out. Finally, a short discussion about the intermittency behavior along a turbine revolution is presented.
Investigation into Window Insulation Retrofitting of Existing Buildings Using Thin and Translucent Frame-Structure Vacuum Insulation Panels
Authors: Yang Zhang , Katsura Takao , Aihara Masahiro , Nakamura Makoto , Nagano Katsunori
Published: January 2018

Insulation performance in older buildings is usually poor, so retrofitting the insulation in these buildings would reduce the energy required for heating, resulting in cost and energy savings. Windows account for a significant amount of the heat loss, therefore, we have developed vacuum layer type vacuum insulation panels (VIPs) with a frame structure that is also slim and lightweight. The developed VIPs are inexpensive and easy to install, as well as being slim and translucent, so retrofitting the window insulation of existing buildings can be easily performed. In this paper, we propose a frame covering with a low emissivity film and a gas barrier envelope coating, with a focus on a reasonable design method. Firstly, a structural model was created to evaluate the safety and specifications of the frame using element mechanical analysis. Next, a finite element model (FEM) was created to predict the insulation performance. Subsequently, experimental validation was completed and the insulation performance was evaluated with the measured thermal conductivity by a guarded hot plate (GHP) apparatus. Finally, case studies were used to evaluate the insulation performance under different conditions. The optimum design included a reasonable frame-structure to hold the vacuum layer with a high insulation thermal conductivity performance of approximately 0.0049 W/(m·K).
Bayesian Based Diagnostic Model for Condition Based Maintenance of Offshore Wind Farms
Authors: Asgarpour Masoud , Sørensen John
Published: January 2018

Operation and maintenance costs are a major contributor to the Levelized Cost of Energy for electricity produced by offshore wind and can be significantly reduced if existing corrective actions are performed as efficiently as possible and if future corrective actions are avoided by performing sufficient preventive actions. This paper presents an applied and generic diagnostic model for fault detection and condition based maintenance of offshore wind components. The diagnostic model is based on two probabilistic matrices; first, a confidence matrix, representing the probability of detection using each fault detection method, and second, a diagnosis matrix, representing the individual outcome of each fault detection method. Once the confidence and diagnosis matrices of a component are defined, the individual diagnoses of each fault detection method are combined into a final verdict on the fault state of that component. Furthermore, this paper introduces a Bayesian updating model based on observations collected by inspections to decrease the uncertainty of initial confidence matrix. The framework and implementation of the presented diagnostic model are further explained within a case study for a wind turbine component based on vibration, temperature, and oil particle fault detection methods. The last part of the paper will have a discussion of the case study results and present conclusions.
Selection of the Best Alternative of Heating System by Environmental Impact Assessment—Case Study
Authors: Ondrejka Harbulakova Vlasta , Zelenakova Martina , Purcz Pavol , Olejnik Adrian
Published: January 2018

The Framework Directive 2009/28/EC on the promotion of the use of energy from renewable sources aims at developing the local and regional electricity market in order to reduce greenhouse gas emissions. A comparison study of the proposed activities of construction of a new biomass-fired power plant or reconstruction of an old one-gas power plant in town located in eastern Slovakia is presented in this paper. The method of the index coefficient was used for choosing the best alternatives. Multicriteria analysis proved that the construction of biomass-fired power plant is the most suitable solution chosen from three assessed variants (no activity is implemented, biomass power plant and modernized gas boiler).
Analysis of Basic Physical-Chemical Parameters, Nutrients and Heavy Metals Content in Surface Water of Small Catchment Area of Karašica and Vučica Rivers in Croatia
Authors: Amić Ana , Tadić Lidija
Published: January 2018

This paper deals with the surface water quality of a small catchment area of the Karašica and Vučica rivers based on the analysis of water physical and chemical parameters according to the national Decree on Water Quality Standards (2013). Water samples were collected and analysed monthly at five sampling stations situated along the watercourses in the period between 1998 and 2015. Analysed parameters were pH, chemical oxygen demand (COD-Mn), five-day biochemical oxygen demand (BOD5), nutrients: nitrate compounds (nitrates and total nitrogen), phosphorus compounds (orthophosphates and total phosphorus), and the content of heavy metals. The obtained results indicate a water quality status between moderate and good, depending on the parameter and sampling station.
Acknowledgement to Reviewers of Epigenomes in 2017
Authors:   Epigenomes Editorial Office
Published: January 2018

Peer review is an essential part in the publication process, ensuring that Epigenomes maintains high quality standards for its published papers. [...]
Biotic Factors Affecting Ecosystem Services in Urban and Peri-Urban Forests in Italy: The Role of Introduced and Impending Pathogens and Pests
Authors: Moricca Salvatore , Bracalini Matteo , Croci Francesco , Corsinovi Sara , Tiberi Riziero , Ragazzi Alessandro , Panzavolta Tiziana
Published: January 2018

The present-day phytosanitary disasters caused by biological invasions are afflicting urban and peri-urban forest stands worldwide, as well as the varied services they normally provide. In Europe, we are witnessing an alarming situation due to an increasing introduction of infectious diseases and pests. The authors present an up-to-date list of alien microbial pathogens and insect pests affecting urban greening that have been accidentally imported in Italy or that are likely to be introduced. Information about the biology, epidemiology, ethology, and control of these invasive organisms is provided. For each species, the current geographical distribution, including newly-colonized areas, is also given, as well as the chronological progression of its occurrence. Particular detail is used for describing symptoms—the key diagnostic elements for appropriate and timely phytosanitary management. This paper will benefit urban forest management, which is a crucial factor in maintaining the social and ecological viability of urban green spaces, as well as ecosystem services. The importance of engaging citizens in community-based monitoring of urban greenspaces for tracking the location, abundance, and pathways of invasive pathogens and pests will also be touched upon.
Effects of Mineral Soil and Forest Floor on the Regeneration of Pedunculate Oak, Beech and Red Oak
Authors: De Groote Stefanie , Vanhellemont Margot , Baeten Lander , Carón María , Martel An , Bonte Dries , Lens Luc , Verheyen Kris
Published: January 2018

Early regeneration is a critical life stage that affects the future species composition of forests. Knowledge about regeneration success under different environmental conditions allows better understanding of forest dynamics. We studied the effects of seedbed conditions on the establishment and performance of seedlings of pedunculate oak, beech and red oak. In 50 plots of a tree-diversity oriented research platform in mature forests in northern Belgium (TREEWEB), we installed a field experiment with three treatments (potting soil, mineral soil, mineral soil + forest floor), in which we sowed seeds of each species. We monitored early establishment and survival, height, root and shoot biomass of the seedlings after two growing seasons. Mineral soil negatively affected seedling establishment and performance relative to the potting soil. The negative soil effects did not vary with measured abiotic soil properties. In general, the forest floor did not deteriorate or mitigate the soil effects, and only for root biomass did the forest floor partly compensate the negative soil effects. Forest floor effects did not vary with the measured forest floor properties. In the studied forests, creating bare soil was not enough to promote regeneration; improving soil properties might be important for the success of natural regeneration.
Biometric and Eddy Covariance Methods for Examining the Carbon Balance of a Larix principis-rupprechtii Forest in the Qinling Mountains, China
Authors: Yuan Jie , Jose Shibu , Hu Zhaoyong , Pang Junzhu , Hou Lin , Zhang Shuoxin
Published: January 2018

The carbon balance of forests is controlled by many component processes of carbon acquisition and carbon loss and depends on the age of vegetation, soils, species composition, and the local climate. Thus, examining the carbon balance of different forests around the world is necessary to understand the global carbon balance. Nevertheless, the available information on the carbon balance of Larix principis-rupprechtii forests in the Qinling Mountains remains considerably limited. We provide the first set of results (2010–2013) from a long-term project measuring forest-atmosphere exchanges of CO2 at the Qinling National Forest Ecosystem Research Station (QNFERS), and compare the net ecosystem exchange (NEE) based on biometric measurements with those observed via the eddy covariance method. We also compare the total ecosystem respiration via scaled-up chamber and eddy covariance measurements. The net primary productivity (NPP) was 817.16 ± 81.48 g·C·m−2·y−1, of which ΔBliving and Dtotal accounted for 77.7%, and 22.3%, respectively. Total ecosystem respiration was 814.47 ± 64.22 g·C·m−2·y−1, and cumulative annual soil respiration, coarse woody debris respiration, stem respiration, and leaf respiration were 715.47 ± 28.48, 15.41 ± 1.72, 35.28 ± 4.78, and 48.31 ± 5.24 g·C·m−2·y−1, respectively, accounting for 87.85%, 1.89%, 4.33%, and 5.93% of the total ecosystem respiration. A comparison between ecosystem respiration from chamber measurements and that from eddy covariance measurements showed a strong linear correlation between the two methods (R2 = 0.93). The NEE of CO2 between forests and the atmosphere measured by eddy covariance was −288.33 ± 25.26 g·C·m−2·y−1, which revealed a carbon sink in the L. principis-rupprechtii forest. This number was 14% higher than the result from the biometric measurements (−336.71 ± 25.15 g·C·m−2·y−1). The study findings provided a cross-validation of the CO2 exchange measured via biometric and eddy covariance, which are beneficial for obtaining the true ecosystem fluxes, and more accurately evaluating carbon budgets.
Spatial Pattern and Temporal Stability of Root-Zone Soil Moisture during Growing Season on a Larch Plantation Hillslope in Northwest China
Authors: Liu Zebin , Wang Yanhui , Yu Pengtao , Tian Ao , Wang Yarui , Xiong Wei , Xu Lihong
Published: January 2018

Soil moisture plays a decisive role for tree growth and forest ecosystems services supply in dryland regions. Hence, it is necessary to clarify the spatio-temporal variation of soil moisture under field conditions. This study selected a hillslope in the Liupan Mountains covered by the plantation of Larix principis-rupprechtii Mayr (larch), a main afforestation tree species in north and northwest China. The volumetric soil moisture (VSM) in root zone layers was monitored with a time interval of about 15 days during the growing season (from May to October) in 2016 at 48 points on this hillslope. The aim was to evaluate the spatial pattern and temporal stability of soil moisture at slope scale. The results showed a moderate spatial variability of VSM in each soil layer, with the variation coefficients range of 17.12–22.63%. The spatial variability of VSM showed a dependence on the soil wetness and a threshold effect, it increased with rising VSM until the VSM reached a threshold of about 15%, but thereafter decreased. The mean relative difference (MRD) among the 48 points ranged from −30.56% to 27.20%, −29.89% to 39.58%, and −28.13% to 33.71% for the soil layers of 0–20, 20–40, and 40–60 cm, respectively. The associated standard deviation (SDRD) (and range) was 11.38% (5.20–26.06%), 8.28% (4.64–15.63%), and 6.51% (2.00–14.16%) for the soil layers of 0–20, 20–40, and 40–60 cm, respectively. The high Spearman’s rank coefficients (p < 0.05) among the measuring dates at each soil layer indicated that the spatial distribution of VSM in the root zone had strong temporal stability. The decrease of Spearman’ rank correlation coefficient and mean SDRD with rising soil depth indicated an increasing temporal stability of VSM with rising soil depth. The mean VSM of the three soil layers on the entire hillslope can be estimated by the direct method (using representative points determined by the index of temporal stability (ITS)) successfully, and these representative points determined by ITS were mainly located at the points with a ratio of field capacity to leaf area index (LAI) close to the slope mean. Moreover, the mean VSM of the three soil layers on the entire hillslope can also be estimated by indirect method (using the time-stable points determined by mean absolute bias error (MABE) and considering the offset between slope mean VSM and observed VSM at time-stable points), and the prediction accuracy of the indirect method was better than the direct method. Significant correlation between MRD and soil bulk density, field capacity, capillary porosity, and LAI were observed for all soil layers, indicating that both the water-retention ability in root zone soil (expressed mainly by field capacity) and water-consumption ability of trees (expressed mainly by canopy LAI) are the main factors controlling the spatial pattern of root-zone VSM on the larch plantation hillslope studied.
Molecular and Phenotypic Characterization of Metschnikowia pulcherrima Strains from Douro Wine Region
Authors: Barbosa Catarina , Lage Patrícia , Esteves Marcos , Chambel Lélia , Mendes-Faia Arlete , Mendes-Ferreira Ana
Published: January 2018

Some non-Saccharomyces yeasts, including Metschnikowia pulcherrima, have been proposed as selected starters due to their contribution for the overall aroma and chemical profiles of wines. In this work, we aimed to evaluate the genetic and phenotypic diversity of Metschnikowia pulcherrima strains isolated from different locations of Douro Wine Region, and to explore their potential as co-adjuncts of S. cerevisiae in alcoholic fermentation. For that purpose, a set of 64 M. pulcherrima isolates were used. Polymerase chain reaction (PCR) fingerprinting with M13 primers demonstrated to be an efficient tool in intraspecific discrimination of M. pulcherrima strains. No significant associations were found between genotypic profiles and either geographical origin or winery. The isolates were screened for their stress resistance ability (ethanol, SO2, chitosan, copper, H2O2, and Grape Juice Medium), aroma-related activities (resistance to 5, 5′, 5′′-trifluor-d, l-leucine and cerulenin and β-glycosidase, β-lyase and sulfite-reductase activities) as well as other relevant technological proprieties (protease activity and biogenic amines production). M. pulcherrima response to the different enological traits evaluated was greatly strain-dependent. The most discriminant features were the ability of the strains to grow in Grape-Juice Medium (GJM) and sulfite-reductase, and their β-lyase and protease activities. The enological potential of a selected M. pulcherrima strain in mixed-culture with S. cerevisiae was also assessed in natural grape-juice of a local variety, under two nitrogen regimes. M. pulcherrima proved to be promising for future industrial application as a co-starter, lowering ethanol, acetic acid and, reported here for the first time, lowering hydrogen sulfide levels in the wines.
The Improved Adaptive Silence Period Algorithm over Time-Variant Channels in the Cognitive Radio System
Authors: Zhang Jingbo , Sun Zhenyang , Zhang Shufang
Published: January 2018

In the field of cognitive radio spectrum sensing, the adaptive silence period management mechanism (ASPM) has improved the problem of the low time-resource utilization rate of the traditional silence period management mechanism (TSPM). However, in the case of the low signal-to-noise ratio (SNR), the ASPM algorithm will increase the probability of missed detection for the primary user (PU). Focusing on this problem, this paper proposes an improved adaptive silence period management (IA-SPM) algorithm which can adaptively adjust the sensing parameters of the current period in combination with the feedback information from the data communication with the sensing results of the previous period. The feedback information in the channel is achieved with frequency resources rather than time resources in order to adapt to the parameter change in the time-varying channel. The Monte Carlo simulation results show that the detection probability of the IA-SPM is 10–15% higher than that of the ASPM under low SNR conditions.
Design of a Novel μ-Mixer
Authors: Kanaris Athanasios , Mouza Aikaterini
Published: January 2018

In this work, the efficiency of a new μ-mixer design is investigated. As in this type of devices the Reynolds number is low, mixing is diffusion dominated and it can be enhanced by creating secondary flows. In this study, we propose the introduction of helical inserts into a straight tube to create swirling flow. The influence of the insert’s geometrical parameters (pitch and length of the propeller blades) and of the Reynolds number on the mixing efficiency and on the pressure drop are numerically investigated. The mixing efficiency of the device is assessed by calculating a number—i.e., the index of mixing efficiency—that quantifies the uniformity of concentration at the outlet of the device. The influence of the design parameters on the mixing efficiency is assessed by performing a series of ‘computational’ experiments, in which the values of the parameter are selected using design of experiments (DOE) methodology. Finally using the numerical data, appropriate design equations are formulated, which, for given values of the design parameters, can estimate with reasonable accuracy both the mixing efficiency and the pressure drop of the proposed mixing device.
Extraction and Optimization of Potato Starch and Its Application as a Stabilizer in Yogurt Manufacturing
Authors: Altemimi Ammar
Published: January 2018

Starch is increasingly used as a functional group in many industrial applications and foods due to its ability to work as a thickener. The experimental values of extracting starch from yellow skin potato indicate the processing conditions at 3000 rpm and 15 min as optimum for the highest yield of extracted starch. The effect of adding different concentrations of extracted starch under the optimized conditions was studied to determine the acidity, pH, syneresis, microbial counts, and sensory evaluation in stored yogurt manufactured at 5 °C for 15 days. The results showed that adding sufficient concentrations of starch (0.75%, 1%) could provide better results in terms of the minimum change in the total acidity, decrease in pH, reduction in syneresis, and preferable results for all sensory parameters. The results revealed that the total bacteria count of all yogurt samples increased throughout the storage time. However, adding different concentrations of optimized extracted starch had a significant effect, decreasing the microbial content compared with the control sample (YC). In addition, the results indicated that coliform bacteria were not found during the storage time.
Constraints on Particles and Fields from Full Stokes Observations of AGN
Authors: Homan Daniel , Hovatta Talvikki , Kovalev Yuri , Lister Matthew , Pushkarev Alexander , Savolainen Tuomas
Published: January 2018

Combined polarization imaging of radio jets from Active Galactic Nuclei (AGN) in circular and linear polarization, also known as full Stokes imaging, has the potential to constrain both the magnetic field structure and particle properties of jets. Although only a small fraction of the emission when detected, typically less than a few tenths of a percent but up to as much as a couple of percent in the strongest resolved sources, circular polarization directly probes the magnetic field and particles within the jet itself and is not expected to be modified by external screens. A key to using full Stokes observations to constrain jet properties is obtaining a better understanding of the emission of circular polarization, including its variability and spectrum. We discuss what we have learned so far from parsec scale monitoring observations in the MOJAVE program and from multi-frequency observations of selected AGN.
The Impact of Climate Change on Water Resource Availability in a Trans-Boundary Basin in West Africa: The Case of Sassandra
Authors: Coulibaly Naga , Coulibaly Talnan , Mpakama Ziyanda , Savané Issiaka
Published: January 2018

In the context of climate change in West Africa characterized by a reduction of precipitation, this study was conducted to evaluate the impact of climate change on water resources from now to the end of the 21st century in the transboundary watershed of the Sassandra River shared by Guinea and Côte d’Ivoire. Historical and future climate data of Representative Concentration Pathways (RCPs) 4.5 and 8.5 were projected with the Abdus Salam International Centre for Theoretical Physics (ICTP) Regional Climate Model (RegCM4). The hydrological modeling of the river basin was carried out with the conceptual hydrological model, GR2M, a monthly time steps model that allows for the assessment of the discharge of the Sassandra River for each climate scenario according to the time periods 2021–2040 (Horizon 2030), 2041–2060 (Horizon 2050), 2061–2080 (Horizon 2050), and 2061–2080 (Horizon 2090). The results show a reduction in annual discharge when compared to the baseline (1961–1980). For RCP 4.5, the observed values go from −1.2% in 2030 to −2.3% in 2070 and rise to −2.1% in 2090. Concerning RCP 8.5, we saw a variation from −4.2 to −7.9% in Horizons 2030 and 2090, respectively. With the general decrease in rainfall in West Africa, it is appropriate to assess the impact on water resources of the largest rivers (Niger, Gambia, and Senegal) that irrigate the Sahelo–Saharian zone.
Long-Term Weight Loss Effects of a Behavioral Weight Management Program: Does the Community Food Environment Matter?
Authors: Zenk Shannon N. , Tarlov Elizabeth , Wing Coady , Matthews Stephen A. , Tong Hao , Jones Kelly K. , Powell Lisa M.
Published: January 2018

This study examined whether community food environments altered the longer-term effects of a nationwide behavioral weight management program on body mass index (BMI). The sample was comprised of 98,871 male weight management program participants and 15,385 female participants, as well as 461,302 and 37,192 inverse propensity-score weighted matched male and female controls. We measured the community food environment by counting the number of supermarkets, convenience stores, and fast food restaurants within a 1-mile radius around each person’s home address. We used difference-in-difference regression models with person and calendar time fixed effects to estimate MOVE! effects over time in sub-populations defined by community food environment attributes. Among men, after an initial decrease in BMI at 6 months, the effect of the program decreased over time, with BMI increasing incrementally at 12 months (0.098 kg/m2, p < 0.001), 18 months (0.069 kg/m2, p < 0.001), and 24 months (0.067 kg/m2, p < 0.001). Among women, the initial effects of the program decreased over time as well. Women had an incremental BMI change of 0.099 kg/m2 at 12 months (p < 0.05) with non-significant incremental changes at 18 months and 24 months. We found little evidence that these longer-term effects of the weight management program differed depending on the community food environment. Physiological adaptations may overwhelm environmental influences on adherence to behavioral regimens in affecting longer-term weight loss outcomes.
The Effect of Childhood Health Status on Adult Health in China
Authors: Wang Qing , Zhang Huyang , Rizzo John , Fang Hai
Published: January 2018

Childhood health in China was poor in the 1950s and 1960s because of limited nutrition. In the last three decades, China has distinguished itself through its tremendous economic growth and improvements in health and nutrition. However, prior to such growth, access to good nutrition was more variable, with potentially important implications, not only for childhood health, but also for adult health, because of its long-term effects lasting into adulthood. To shed light on these issues, this study examined the long-run association between childhood health and adult health outcomes among a middle-aged Chinese population and addresses the endogeneity of childhood health. A nationwide database from the 2011 China Health and Retirement Longitudinal Study (CHARLS) was employed. Three adult health outcomes variables were used: self-reported health status, cognition, and physical function. The local variation in grain production in the subjects’ fetal period and the first 24 months following birth was employed as an instrument for childhood health in order to correct for its endogeneity. Childhood health recalled by the respondents was positively and significantly associated with their adult health outcomes in terms of self-reported health status, cognition, and physical function in single-equation estimates that did not correct for the endogeneity of childhood health. A good childhood health status increased the probabilities of good adult health, good adult cognitive function, and good adult physical function by 16% (95% CI: 13–18%), 13% (95% CI: 10–15%), and 14% (95% CI: 12–17%), respectively. After correcting for endogeneity, the estimated effects of good childhood health were consistent but stronger. We also studied the male and female populations separately, finding that the positive effects of childhood health on adult health were larger for males. In China, childhood health significantly affects adult health. This suggests that early interventions to promote childhood health will have long-term benefits in China and that health-care policies should consider their long-term impacts over the life cycle in addition to their effects on specific age groups.
Study of Stroke Incidence in the Aseer Region, Southwestern Saudi Arabia
Authors: Alhazzani Adel , Mahfouz Ahmed , Abolyazid Ahmed , Awadalla Nabil , Aftab Razia , Faraheen Aesha , Khalil Shamsun
Published: January 2018

Recent data regarding first-stroke incidence in Saudi Arabia in general and in the Aseer region in particular are scarce and even lacking. The aim of this work was to study the first-time stroke incidence in the Aseer region, southwestern Saudi Arabia. All first-stroke patients admitted to all hospitals in the Aseer region over a one-year period (January through December 2016) were included. Stroke patients outside the Aseer region were excluded from the study. The incidence per 100,000 patients and the concomitant 95% CI (Confidence Intervals) were computed. The present study included 1249 first-time stroke patients and calculated an overall minimal incidence rate of hospitalized first-time stroke of 57.64 per 100,000 persons per year (95% CI: 57.57–57.70). A steady increase was noticed depending on the patients' age, reaching a figure of 851.81 (95% CI: 849.2–854.5) for those patients aged 70 years and more. Overall, the incidence rate for females (48.14; 95% CI: 48.04–48.24) was lower compared to males (65.52; 95% CI: 65.1–66.0). Taking into consideration the expected rise of the elderly because of the prominent medical services provided by the Saudi government, leading to a subsequent change in the horizontal and vertical age distribution structure of the population, an increase in the number of stroke patients is expected. It is suggested to establish a nationwide stroke surveillance system in the Kingdom, with the objective to report, analyze, and maintain an updated overview of the stroke status in Saudi Arabia.
Intention for Car Use Reduction: Applying a Stage-Based Model
Authors: Olsson Lars E. , Huck Jana , Friman Margareta
Published: January 2018

This study investigates which variables drive intention to reduce car use by modelling a stage of change construct with mechanisms in the Theory of Planned Behavior (TPB) and Norm Activation Model (NAM). Web questionnaires (n = 794) were collected via 11 workplaces. The socio-demographics, work commute, stage of change, attitudes to sustainable travel modes, social norms, perceived behavioral control, and personal norm were assessed. An initial descriptive analysis revealed that 19% of the employees saw no reason to reduce their car use; 35% would like to reduce their car use but felt it was impossible; 12% were thinking about reducing their car use but were unsure of how or when to do this; 12% had an aim to reduce current car use, and knew which journeys to replace and which modes to use; and 23% try to use modes other than a car for most journeys, and will maintain or reduce their already low car use in the coming months. A series of Ordered Logit Models showed that socio-demographic variables did not explain the stage of change. Instead, personal norms, instrumental and affective attitudes, and perceived behavioral control toward sustainable travel modes were all significant and explained 43% of the variance in stage of change. Furthermore, it was found that the significant relationships were not linear in nature. The analysis also showed an indirect effect of social norms on the stage of change through personal norms. Implications are discussed regarding the design of interventions aimed at influencing a sustainable work commute.