bluuebunny/crossref_metadata_2025 huggingface dataset:
Reducing WCET Overestimations in Multi-Thread Loops with Critical Section Usage
Authors: Ramanauskaite Simona , Slotkiene Asta , Tunaityte Kornelija , Suzdalev Ivan , Stankevicius Andrius , Valentinavicius Saulius
Published: March 2021

Worst-case execution time (WCET) is an important metric in real-time systems that helps in energy usage modeling and predefined execution time requirement evaluation. While basic timing analysis relies on execution path identification and its length evaluation, multi-thread code with critical section usage brings additional complications and requires analysis of resource-waiting time estimation. In this paper, we solve a problem of worst-case execution time overestimation reduction in situations when multiple threads are executing loops with the same critical section usage in each iteration. The experiment showed the worst-case execution time does not take into account the proportion between computational and critical sections; therefore, we proposed a new worst-case execution time calculation model to reduce the overestimation. The proposed model results prove to reduce the overestimation on average by half in comparison to the theoretical model. Therefore, this leads to more accurate execution time and energy consumption estimation.
Collective Losses of Low Power Cage Induction Motors—A New Approach
Authors: Szychta Elzbieta , Szychta Leszek
Published: March 2021

Energy efficiency of systems of water pumping is a complex problem since efficiency of two distinct interacting systems needs to be combined: water and power supply. This paper introduces a non-intrusive method of calculating the so-called “collective losses” of a cage induction motor. The term “collective losses”, which the authors define, allows for accurate estimation of motor efficiency. Control system of a pump determines operating point of a pumping station, and thus its efficiency. General estimated performance characteristics of a motor, components of a control system, are assumed to serve selection of a range of pumping speed variations. Rotational speed has a direct effect on motor load torque, pump power and head, and thus on motor performance. Hellwig’s statistical method was used to specify characteristics of estimated collective losses on the basis of experimental studies of 21 motors rated at up to 2.2 kW. The results of simulations and experiments are used to verify validity and efficiency of the suggested method. The method is non-intrusive, simple to use, and requires minimum data.
Gate Drive Controller for Low Voltage DC Hybrid Circuit Breaker
Authors: Kim Hyosung
Published: March 2021

With the advent of direct current (DC) loads such as LED lighting, IT equipment, electric vehicles, and DC powers generated from renewable energy sources, low voltage DC (LVDC) distribution system is becoming a hot issue. One of the hurdles in the LVDC distribution system is arc flash at the contact points that occurs during the circuit is opening. Unlike alternating current, direct current has no zero points and sustains constantly. Therefore, there is a risk of electric fire due to continuous generating arcs when the load current is interrupted with an existing electrical contact type circuit breaker. Recently, the concept of a hybrid circuit breaker that takes advantage of traditional electrical contact type switch and the arcless semiconductor switch has been proposed, but how to cooperatively operate the two switches has become an issue. This paper analyzes the principle of a hybrid circuit breaker for blocking LVDC current and proposes a gate drive controller for it. Through 400V class LVDC cutoff test, the operation of the proposed hybrid circuit breaker is verified and the characteristics are analyzed.
Pressure Exchanger for Energy Recovery in a Trans-Critical CO2 Refrigeration System
Authors: Elatar Ahmed , Fricke Brian , Sharma Vishaldeep , Nawaz Kashif
Published: March 2021

Trans-critical CO2 vapor compression (VC) refrigeration cycles require a high compression ratio, which is associated with high expansion losses. To recover these expansion losses, a pressure exchange process between the low- and high-pressure sides of the VC cycle is proposed and examined in this study. The proposed pressure exchange system is an open type constant volume process where the high- and low-pressure flows mix inside the system. This prototype is inspired by the pressure exchangers used in reverse-osmosis (RO) desalination systems. In this system, a 2D model was generated and modeled using the computational fluid dynamics (CFD) technique. The numerical model ignored any losses due to leakage or hydraulic friction and the process is considered adiabatic. For the modeling, it was assumed that the inlet conditions for the two pressure exchanger flows are similar to the flow conditions at the evaporator and gas cooler outlets in a VC cycle. Two parameters are examined to test the validity of the system and understand their effect on the performance, including the inlet flow rate represented by the inlet velocity and the process time represented by the speed of rotation. A total of nine cases were simulated and analyzed in this study.
Tribo-Electrostatic Separation Analysis of a Beneficial Solution in the Recycling of Mixed Poly(Ethylene Terephthalate) and High-Density Polyethylene
Authors: Lyskawinski Wieslaw , Baranski Mariusz , Jedryczka Cezary , Mikolajewicz Jacek , Regulski Roman , Sedziak Dariusz , Netter Krzysztof , Rybarczyk Dominik , Czarnecka-Komorowska Dorota , Barczewski Mateusz
Published: March 2021

The aim of this study was to investigate and analyze the impact of selected parameters during the tribocharging process of shredded poly(ethylene terephthalate) (PET) and high-density polyethylene (PE-HD) plastics on accumulated electric charge and electrostatic separation effectiveness. The accumulation of electric charge on surfaces of polymer particles as a result of their circular motion forced by the airflow cyclone container was investigated. The impact of the container material, time of tribocharging and the airflow intensity were experimentally examined. A container in which the particles of the considered polymers are electrified with opposite charges was selected. A high ability to accumulate surface charge on small particles of both polymers was demonstrated. The electrified mixed PET/PE-HD was subjected to a separation process. An electrostatic separator designed and constructed by the authors was used for to the separation. In turn, to assess the effectiveness of this separation, a dedicated vision system was used. Based on the result of the carried out tests, it has been assumed that the proposed approach’s effectiveness has been demonstrated by means of empirical validation.
Analysis and Pareto Frontier Based Tradeoff Design of an Integrated Magnetic Structure for a CLLC Resonant Converter
Authors: Wang Gang , Hu Qiyu , Xu Chunyu , Zhao Bin , Su Xiaobao
Published: March 2021

This paper proposes an integrated magnetic structure for a CLLC resonant converter. With the proposed integrated magnetic structure, two resonant inductances and the transformer are integrated into one magnetic core, which improves the power density of the CLLC resonant converter. In the proposed integrated magnetic structure, two resonant inductances are decoupled with the transformer and can be adjusted by the number of turns in each inductance. Furthermore, two resonant inductances are coupled to reduce the number of turns in each inductance. As a result, the conduction loss can be reduced. The trade-off design of the integrated magnetic structure is carried out based on the Pareto optimization procedure. With the Pareto optimization procedure, both high efficiency and high-power density can be achieved. The proposed integrated magnetic structure is validated by theoretical analysis, simulations, and experiments.
Microscale Processes and Dynamics during CH4–CO2 Guest-Molecule Exchange in Gas Hydrates
Authors: Kossel Elke , Bigalke Nikolaus K. , Deusner Christian , Haeckel Matthias
Published: March 2021

The exchange of CH4 by CO2 in gas hydrates is of interest for the production of natural gas from methane hydrate with net zero climate gas balance, and for managing risks that are related to sediment destabilization and mobilization after gas-hydrate dissociation. Several experimental studies on the dynamics and efficiency of the process exist, but the results seem to be partly inconsistent. We used confocal Raman spectroscopy to map an area of several tens to hundreds µm of a CH4 hydrate sample during its exposure to liquid and gaseous CO2. On this scale, we could identify and follow different processes in the sample that occur in parallel. Next to guest-molecule exchange, gas-hydrate dissociation also contributes to the release of CH4. During our examination period, about 50% of the CO2 was bound by exchange for CH4 molecules, while the other half was bound by new formation of CO2 hydrates. We evaluated single gas-hydrate grains with confirmed gas exchange and applied a diffusion equation to quantify the process. Obtained diffusion coefficients are in the range of 10−13–10−18 m2/s. We propose to use this analytical diffusion equation for a simple and robust modeling of CH4 production by guest-molecule exchange and to combine it with an additional term for gas-hydrate dissociation.
Two-Step Predict and Correct Non-Intrusive Parametric Model Order Reduction for Changing Well Locations Using a Machine Learning Framework
Authors: Zalavadia Hardikkumar , Gildin Eduardo
Published: March 2021

The objective of this paper is to develop a two-step predict and correct non-intrusive Parametric Model Order Reduction (PMOR) methodology for the problem of changing well locations in an oil field that can eventually be used for well placement optimization to gain significant computational savings. In this work, we propose a two-step PMOR procedure, where, in the first step, a Proper Orthogonal Decomposition (POD)-based strategy that is non-intrusive to the simulator source code is introduced, as opposed to the convention of using POD as a simulator intrusive procedure. The non-intrusiveness of the proposed technique stems from formulating a novel Machine Learning (ML)-based framework used with POD. The features of the ML model (Random Forest was used here) are designed such that they take into consideration the temporal evolution of the state solutions and thereby avoid simulator access for the time dependency of the solutions. The proposed PMOR method is global, since a single reduced-order model can be used for all the well locations of interest in the reservoir. We address the major challenge of the explicit representation of the well location change as a parameter by introducing geometry-based features and flow diagnostics-inspired physics-based features. In the second step, an error correction model based on reduced model solutions is formulated to correct for discrepancies in the state solutions at well grid blocks expected from POD basis for new well locations. The error correction model proposed uses Artificial Neural Networks (ANNs) that consider the physics-based reduced model solutions as features, and is proved to reduce the error in QoI (Quantities of Interest), such as oil production rates and water cut, significantly. This workflow is applied to a simple homogeneous reservoir and a heterogeneous channelized reservoir using a section of SPE10 model that showed promising results in terms of model accuracy. Speed-ups of about 50×–100× were observed for different cases considered when running the test scenarios. The proposed workflow for Reduced-Order Modeling is “non-intrusive” and hence can increase its applicability to any simulator used. Additionally, the method is formulated such that all the simulation time steps are independent and hence can make use of parallel resources very efficiently and also avoid stability issues that can result from error accumulation over time steps.
Conversion of Slaughterhouse Wastes to Solid Fuel Using Hydrothermal Carbonization
Authors: Lee Jongkeun , Cho Sungwan , Kim Daegi , Ryu JunHee , Lee Kwanyong , Chung Haegeun , Park Ki Young
Published: March 2021

In this study, cattle and pig slaughterhouse wastes (SHWs) were hydrothermally carbonized at 150–300 °C, and the properties of SHW-derived hydrochar were evaluated for its use as a solid fuel. The results demonstrated that increasing the hydrothermal carbonization (HTC) treatment temperature improved the energy-related properties (i.e., fuel ratio, higher heating value, and coalification degree) of both the cattle and pig SHW-derived hydrochars. However, the improvements of cattle SHW-derived hydrochars were not as dramatic as that of pig SHW-derived hydrochars, due to the lipid-rich components that do not participate in the HTC reaction. In this regard, there was no merit of using HTC treatment on cattle SHW for the production of hydrochar or using the hydrochar as a solid fuel in terms of energy retention efficiency. On the other hand, a mild HTC treatment at approximately 200 °C was deemed suitable for converting pig SHW to value-added solid fuel. The findings of this study suggest that the conversion of SHWs to hydrochar using HTC can provide an environmentally benign method for waste treatment and energy recovery from abandoned biomass. However, the efficiency of energy recovery varies depending on the chemical composition of the raw feedstock.
In Situ Tests of the Monitoring and Diagnostic System for Individual Photovoltaic Panels
Authors: Woszczyński Mariusz , Rogala-Rojek Joanna , Bartoszek Sławomir , Gaiceanu Marian , Filipowicz Krzysztof , Kotwica Krzysztof
Published: March 2021

The dynamic development of photovoltaic systems in the world and in Poland is mainly related to the drop in prices of installation components. Currently, electricity from photovoltaics is one of the cheapest renewable energy sources. The basis for effective energy generation is, first of all, failure-free operation of the photovoltaic system over a long period of operation, up to 30 years. The paper presents the results of a study of a low-cost distributed system for monitoring and diagnosis of photovoltaic installations (SmartPV), capable of assessing the operating parameters of individual photovoltaic panels. The devices were tested by connecting them to an existing photovoltaic installation, allowing the measurement of operational parameters of individual photovoltaic panels as well as operating conditions such as illuminance and panel surface temperature. The data were recorded on a server using wireless Wi-Fi transmission. Interesting data were collected during the tests, confirming the usefulness of the suggested device for monitoring the photovoltaic installations. Differences in performance of the photovoltaic panel depending on solar radiation and surface temperature were recorded. The temperature coefficient of power was determined, allowing for increased accuracy in the prediction of generated power. The correct recording in different situation, i.e., shading, sensor damage or weather anomalies, was verified. Based on the collected data, rules will be defined for an expert application which, in combination with SmartPV devices, will ensure a quick response to any malfunctions of the photovoltaic system, both related to failures and those resulting from natural degradation during operation.
Prenatal Exposure to Persistent Organic Pollutants and Maternal Folic Acid Supplementation: Their Impact on Glucose Homeostasis in Male Rat Descendants
Authors: Navarro Pauline , Dalvai Mathieu , L. Charest Phanie , Herst Pauline M. , Lessard Maryse , Marcotte Bruno , Leblanc Nadine , Kimmins Sarah , Trasler Jacquetta , MacFarlane Amanda J. , Marette André , L. Bailey Janice , Jacques Hélène
Published: March 2021

Exposure to persistent organic pollutants (POPs) is associated with insulin resistance while folic acid (FA) may offer a protective effect. However, the paternal contribution to metabolic phenotypes in offspring is not well known yet. Hence, we investigated whether maternal exposure to POPs affects glucose homeostasis and whether maternal FA supplementation counteracts POP effects transmitted via male descendants. Sprague–Dawley founder dams (F0) were fed a diet containing 2 or 6 mg/kg of FA and were force-fed with either a POP mixture or corn oil for 9 weeks. Subsequent male descendants did not receive any treatment. Blood glucose, plasma insulin and C-peptide were measured during an oral glucose tolerance test in males aged 90 and 180 days from generation 1 (F1), 2 (F2) and 3 (F3). Prenatal POP exposure increased fasting glucose in 90-day-old F1 males and C-peptide in 90-day-old F2 males. Prenatal FA supplementation decreased C-peptide in 90 and 180-day-old F1 males. In 180-day-old F3 males, FA supplementation counteracted POPs on fasting and postglucose C-peptide, indicating reduced insulin secretion. Prenatal exposure to an environmentally relevant POP mixture caused abnormalities in glucose homeostasis that are transmitted from one generation to the next through the paternal lineage. Prenatal FA supplementation counteracted some of the deleterious effects of POPs on glucose homeostasis.
Hybridisation of Malus sylvestris (L.) Mill. with Malus × domestica Borkh. and Implications for the Production of Forest Reproductive Material
Authors: Kišek Mateja , Jarni Kristjan , Brus Robert
Published: March 2021

This study focuses on the morphological and genetic characteristics of European crab apple (Malus sylvestris (L.) Mill.) and the occurrence of hybrids in its populations. We analyzed a total of 107 putative European crab apple trees in Slovenia: 92 from nine natural populations, five from a seed stand and 10 from a stand of unnatural origin. We also included 18 domesticated apple trees (Malus × domestica Borkh.) and two Japanese flowering crab apple trees (Malusfloribunda van Houtte) as outliers. The trees were classified into groups of European crab apples, hybrids and domesticated apples according to their morphological and genetic characteristics. Classification based on morphological traits produced different results (58.75% European crab apple, 37.11% hybrids and 4.14% domesticated apple) compared to those based on genetic analysis (70.10% European crab apple, 21.64% hybrids and 8.26% domesticated apple). When genetic and morphological characteristics were combined, only 40.20% of the trees were classified as European crab apple, and an additional group of feral cultivars of domesticated apples (6.18%) was identified. The analysis revealed that hybridization with domesticated apple is taking place in all studied natural European crab apple populations; however, hybrids and feral cultivars only occur to a limited extent. When introducing European crab apple into forests in the future, only genetically verified forest reproductive material obtained exclusively from suitable seed stands should be used.
Modelling Maritime Pine (Pinus pinaster Aiton) Spatial Distribution and Productivity in Portugal: Tools for Forest Management
Authors: Alegria Cristina , Roque Natália , Albuquerque Teresa , Fernandez Paulo , Ribeiro Maria Margarida
Published: March 2021

Research Highlights: Modelling species’ distribution and productivity is key to support integrated landscape planning, species’ afforestation, and sustainable forest management. Background and Objectives: Maritime pine (Pinus pinaster Aiton) forests in Portugal were lately affected by wildfires and measures to overcome this situation are needed. The aims of this study were: (1) to model species’ spatial distribution and productivity using a machine learning (ML) regression approach to produce current species’ distribution and productivity maps; (2) to model the species’ spatial productivity using a stochastic sequential simulation approach to produce the species’ current productivity map; (3) to produce the species’ potential distribution map, by using a ML classification approach to define species’ ecological envelope thresholds; and (4) to identify present and future key factors for the species’ afforestation and management. Materials and Methods: Spatial land cover/land use data, inventory, and environmental data (climate, topography, and soil) were used in a coupled ML regression and stochastic sequential simulation approaches to model species’ current and potential distributions and productivity. Results: Maritime pine spatial distribution modelling by the ML approach provided 69% fitting efficiency, while species productivity modelling achieved only 43%. The species’ potential area covered 60% of the country’s area, where 78% of the species’ forest inventory plots (1995) were found. The change in the Maritime pine stands’ age structure observed in the last decades is causing the species’ recovery by natural regeneration to be at risk. Conclusions: The maps produced allow for best site identification for species afforestation, wood production regulation support, landscape planning considering species’ diversity, and fire hazard mitigation. These maps were obtained by modelling using environmental covariates, such as climate attributes, so their projection in future climate change scenarios can be performed.
Trade-Offs among Release Treatments in Jack Pine Plantations: Twenty-Five Year Responses
Authors: Deighton Holly D. , Bell Frederick Wayne , Thiffault Nelson , Searle Eric B. , Leitch Mathew , Sharma Mahadev , Dacosta Jennifer
Published: March 2021

We assessed 27 indicators of plant diversity, stand yield and individual crop tree responses 25 years post-treatment to determine long-term trade-offs among conifer release treatments in boreal and sub-boreal forests. This research addresses the lack of longer-term data needed by forest managers to implement more integrated vegetation management programs, supporting more informed decisions about release treatment choice. Four treatments (untreated control, motor-manual brushsaw, single aerial spray, and complete competition removal) were established at two jack pine (Pinus banksiana Lamb.) sites in Ontario, Canada. Our results suggest that plant diversity and productivity in boreal jack pine forests are significantly influenced by vegetation management treatments. Overall, release treatments did not cause a loss of diversity but benefitted stand-scale yield and individual crop tree growth, with maximum benefits occurring in more intensive release treatments. However, none of the treatments maximized all 27 indicators studied; thus, forest managers are faced with trade-offs when choosing treatments. Research on longer term effects, ideally through at least one rotation, is essential to fully understand outcomes of different vegetation management on forest diversity, stand yield, and individual crop tree responses.
Wood Modification as a Tool to Understand Moisture in Wood
Authors: Thybring Emil Engelund , Fredriksson Maria
Published: March 2021

Moisture plays a central role in the performance of wood products because it affects important material properties such as the resistance to decomposition, the mechanical properties, and the dimensions. To improve wood performance, a wide range of wood modification techniques that alter the wood chemistry in various ways have been described in the literature. Typically, these modifications aim to improve resistance to decomposition, dimensional stability, or, to introduce novel functionalities in the wood. However, wood modification techniques can also be an important tool to improve our understanding of the interactions between wood and moisture. In this review, we describe current knowledge gaps in our understanding of moisture in wood and how modification has been and could be used to clarify some of these gaps. This review shows that introducing specific chemical changes, and even controlling the distribution of these, in combination with the variety of experimental methods available for characterization of moisture in wood, could give novel insights into the interaction between moisture and wood. Such insights could further contribute to applications in several related fields of research such as how to enhance the resistance to decomposition, how to improve the performance of moisture-induced wooden actuators, or how to improve the utilization of wood biomass with challenging swelling anisotropy.
Growth Rates of Poplar Cultivars across Central Asia
Authors: Thevs Niels , Fehrenz Steffen , Aliev Kumar , Emileva Begaiym , Fazylbekov Rinat , Kentbaev Yerzhan , Qonunov Yodgor , Qurbonbekova Yosumin , Raissova Nurgul , Razhapbaev Muslim , Zikirov Sovietbek
Published: March 2021

Research Highlights: Despite a long tradition of using poplars as wood source across Central Asia, recent international breeding developments have not penetrated that region yet. This study therefore explored growth performance of 30 local and international poplar cultivars. Background and Objectives: The Central Asian countries are forest poor countries, which need to cover the domestic wood demand through costly imports. Therefore, fast growing trees, such as poplars, are gaining increasing attention as option to grow wood domestically. The most common cultivars date back to Soviet Union times. As recent breeding developments have not reached the region, this study aims at investigate the growth performance of a number of newly developed poplar cultivars. Materials and Methods: The investigated cultivars were planted as cuttings across nine sites in Kyrgyzstan, Kazakhstan, and Tajikistan between 2018 and 2020. Results: Under warm climate conditions, i.e., low elevations, P. deltoides x nigra hybrids attained highest stem volumes and biomass yields, up to 16.9 t/ha*a after two years, followed by P. nigra xmaximoviczii hybrids. One of the P. deltoides xnigra hybrids reached a tree height of 10.5 m after three years. On higher elevations, e.g., in the Pamirs and in Naryn, P. maximoviczi x trichocarpa hybrids and P. trichocarpa cultivars grew faster than the former hybrids. Conclusions: The cultivars explored in this study should be included into plantations or agroforestry systems that are being established, provided that land users are able to thoroughly control weeds and ensure nutrient and water supply. If sufficient weed control, nutrient supply, or water supply cannot be ensured, then land users should opt for local cultivars (e.g., Mirza Terek) or the P. nigra xmaximoviczii hybrids or P. trichocarpa, in order to avoid failure.
Can a Remote Sensing Approach with Hyperspectral Data Provide Early Detection and Mapping of Spatial Patterns of Black Bear Bark Stripping in Coast Redwoods?
Authors: Magstadt Shayne , Gwenzi David , Madurapperuma Buddhika
Published: March 2021

The prevalence of black bear (Ursus americanus) bark stripping in commercial redwood (Sequoia sempervirens (D. Don) Endl.) timber stands has been increasing in recent years. This stripping is a threat to commercial timber production because of the deleterious effects on redwood tree fitness. This study sought to unveil a remote sensing method to detect these damaged trees early and map their spatial patterns. By developing a timely monitoring method, forest timber companies can manipulate their timber harvesting routines to adapt to the consequences of the problem. We explored the utility of high spatial resolution UAV-collected hyperspectral imagery as a means for early detection of individual trees stripped by black bears. A hyperspectral sensor was used to capture ultra-high spatial and spectral information pertaining to redwood trees with no damage, those that have been recently attacked by bears, and those with old bear damage. This spectral information was assessed using the Jeffries-Matusita (JM) distance to determine regions along the electromagnetic spectrum that are useful for discerning these three-health classes. While we were able to distinguish healthy trees from trees with old damage, we were unable to distinguish healthy trees from recently damaged trees due to the inherent characteristics of redwood tree growth and the subtle spectral changes within individual tree crowns for the time period assessed. The results, however, showed that with further assessment, a time window may be identified that informs damage before trees completely lose value.
A Review of Dynamic Tree Behaviors: Measurement Methods on Tree Sway, Tree Tilt, and Root–Plate Movement
Authors: Yang Zi , Hui Ka Wai , Abbas Sawaid , Zhu Rui , Kwok Coco Yin Tung , Heo Joon , Ju Sungha , Wong Man Sing
Published: March 2021

Urban forest ecosystems are being developed to provide various environmental services (e.g., the preservation of urban trees) to urban inhabitants. However, some trees are deteriorated asymptomatically without exhibiting an early sign of tree displacement, which results in a higher vulnerability under dynamic wind loads, especially during typhoon seasons, in the subtropical and tropical regions. As such, it is important to understand the tilt and sway behaviors of trees to cope up with the probability of tree failure and to improve the efficacy of tree management. Tree behaviors under wind loads have been broadly reviewed in the past literature, yet thorough discussions on the measurement methods for tree displacement and its analysis of broadleaf specimens are lacking. To understand the behavioral pattern of both broadleaf and conifer species, this paper presents a detailed review of sway behavior analysis from the perspectives of the aerial parts of the individual tree, including tree stem, canopy, and trunk, alongside a highlighted focus on the root–plate movement amid the soil-root system. The analytical approaches associated with the time-space domain and the time-frequency domain are being introduced. In addition to the review of dynamic tree behaviors, an integrated tree monitoring framework based on geographic information systems (GIS) to detect and visualize the extent of tree displacement using smart sensing technology (SST) is introduced. The monitoring system aims to establish an early warning indicator system for monitoring the displacement angles of trees over the territory of Hong Kong’s urban landscape. This pilot study highlights the importance of the monitoring system at an operational scale to be applicable in the urban areas showcasing the practical use of the Internet of Things (IoT) with an in-depth understanding of the wind-load effect toward the urban trees in the tropical and subtropical cities.
An Adaptive Throughput-First Packet Scheduling Algorithm for DPDK-Based Packet Processing Systems
Authors: Li Chuanhong , Song Lei , Zeng Xuewen
Published: March 2021

The continuous increase in network traffic has sharply increased the demand for high-performance packet processing systems. For a high-performance packet processing system based on multi-core processors, the packet scheduling algorithm is critical because of the significant role it plays in load distribution, which is related to system throughput, attracting intensive research attention. However, it is not an easy task since the canonical flow-level packet scheduling algorithm is vulnerable to traffic locality, while the packet-level packet scheduling algorithm fails to maintain cache affinity. In this paper, we propose an adaptive throughput-first packet scheduling algorithm for DPDK-based packet processing systems. Combined with the feature of DPDK burst-oriented packet receiving and transmitting, we propose using Subflow as the scheduling unit and the adjustment unit making the proposed algorithm not only maintain the advantages of flow-level packet scheduling algorithms when the adjustment does not happen but also avoid packet loss as much as possible when the target core may be overloaded Experimental results show that the proposed method outperforms Round-Robin, HRW (High Random Weight), and CRC32 on system throughput and packet loss rate.
Emulsions Incorporated in Polysaccharide-Based Active Coatings for Fresh and Minimally Processed Vegetables
Authors: Ramos Marina , Mellinas Cristina , Solaberrieta Ignacio , Garrigós María Carmen , Jiménez Alfonso
Published: March 2021

The consumption of minimally processed fresh vegetables has increased by the consumer’s demand of natural products without synthetic preservatives and colorants. These new consumption behaviors have prompted research on the combination of emulsion techniques and coatings that have traditionally been used by the food industries. This combination brings great potential for improving the quality of fresh-cut fruits and vegetables by allowing the incorporation of natural and multifunctional additives directly into food formulations. These antioxidant, antibacterial, and/or antifungal additives are usually encapsulated at the nano- or micro-scale for their stabilization and protection to make them available by food through the coating. These nano- or micro-emulsions are responsible for the release of the active agents to bring them into direct contact with food to protect it from possible organoleptic degradation. Keeping in mind the widespread applications of micro and nanoemulsions for preserving the quality and safety of fresh vegetables, this review reports the latest works based on emulsion techniques and polysaccharide-based coatings as carriers of active compounds. The technical challenges of micro and nanoemulsion techniques, the potential benefits and drawbacks of their use, the development of polysaccharide-based coatings with natural active additives are considered, since these systems can be used as alternatives to conventional coatings in food formulations.
Effect of NaCl Partial Replacement by Chloride Salts on Physicochemical Characteristics, Volatile Compounds and Sensorial Properties of Dry-Cured Deer Cecina
Authors: Vargas-Ramella Marcio , Lorenzo José M. , Domínguez Rubén , Pateiro Mirian , Munekata Paulo E. S. , Campagnol Paulo C. B. , Franco Daniel
Published: March 2021

The present study aimed to evaluate the effect of NaCl replacement in the physicochemical quality and volatile and sensorial profile of dry-cured deer cecina. Two salt mixtures were used as NaCl substitute: mixture I (30% NaCl-70% KCl) and mixture II (30% NaCl-50% KCl-15% CaCl2-5% MgCl2). Regarding the physicochemical parameters, only ash content, pH and L* values were affected by NaCl replacement. However, lipid oxidation was affected by NaCl replacement. The greatest thiobarbituric acid reactive substances (TBARS) values were observed in the control batch (3.28 mg MDA/kg). The partial replacement of NaCl by salt mixtures affected (p < 0.001) Ca, K, Mg, and Na content. The total amounts of free fatty acids and free amino acids were not affected (p > 0.05) by NaCl replacement. Concerning the volatile compounds, control samples presented the highest concentrations of furans (p < 0.01), while samples produced with mixture II had the lowest (p < 0.001) amounts of esters and acids. Our results indicated that all sensory attributes of the attribute map were affected (generalized procrustes analysis (GPA) explained 100% of the total variability among treatments). Considering the results obtained from the sensorial analysis, only mixture II reduced the overall acceptance and preference of consumers. Control attained significantly (p < 0.05) greater scores of acceptance and preference than mixture II despite the higher TBARS content.
Primary Processing and Storage Affect the Dominant Microbiota of Fresh and Chill-Stored Sea Bass Products
Authors: Syropoulou Faidra , Parlapani Foteini F. , Kakasis Stefanos , Nychas George-John E. , Boziaris Ioannis S.
Published: March 2021

The cultivable microbiota isolated from three sea bass products (whole, gutted, and filleted fish from the same batch) during chilled storage and the effect of primary processing on microbial communities in gutted and filleted fish were studied. Microbiological and sensory changes were also monitored. A total of 200 colonies were collected from TSA plates at the beginning and the end of fish shelf-life, differentiated by High Resolution Sequencing (HRM) and identified by sequencing analysis of the V3–V4 region of the 16S rRNA gene. Pseudomonas spp. followed by potential pathogenic bacteria were initially found, while Pseudomonasgessardii followed by other Pseudomonas or Shewanella species dominated at the end of fish shelf-life. P. gessardii was the most dominant phylotype in the whole sea bass, P. gessardii and S. baltica in gutted fish, while P. gessardii and P. fluorescens were the most dominant bacteria in sea bass fillets. To conclude, primary processing and storage affect microbial communities of gutted and filleted fish compared to the whole fish. HRM analysis can easily differentiate bacteria isolated from fish products and reveal the contamination due to handling and/or processing, and so help stakeholders to immediately tackle problems related with microbial quality or safety of fish.
Grapes and Their Derivatives in Functional Foods
Authors: Kandylis Panagiotis
Published: March 2021

Consumer interest in the consumption of health promoting foods is growing worldwide due to the realization of the link between diet and human health [...]
Chemical Profile and Bioactivities of Extracts from Edible Plants Readily Available in Portugal
Authors: Silva Beatriz , Cadavez Vasco , Ferreira-Santos Pedro , Alves Maria , Ferreira Isabel , Barros Lillian , Teixeira José , Gonzales-Barron Ursula
Published: March 2021

Plant extracts have been proposed as alternative biocides and antioxidants to be included in a variety of food products. In this work, to assess the potential of French lavender, lemon balm, basil, tarragon, sage, and spearmint to be used as food additives, the chemical profiles and bioactivities of such plant extracts were studied. Furthermore, to evaluate the influence of extraction methods and solvents on the chemical characteristics and bioactivities of the plant extracts, two extraction methods (solid-liquid and Soxhlet extraction) and two solvents (water and ethanol 70% (v/v)) were tested for each plant. Groupwise summary statistics were calculated by plant, extraction method, and solvent, and linear models were built to assess the main effects of those terms and their interactions on the chemical characteristics and bioactivities of the extracts. The results revealed that all factors—type of plant, extraction method and solvent—have influence on the chemical profile and antioxidant activity of the resultant extracts. Interactions between factors were also observed. Hydroethanolic Soxhlet extracts presented the least potential as biopreservatives due to their low phenolic content and reduced antioxidant capacity. Oppositely, aqueous Soxhlet extracts and hydroethanolic solid-liquid extracts showed high contents in phenolic compounds and high antioxidant activities. In particular, the hydroethanolic solid-liquid extracts of lemon balm, spearmint, and sage presented the highest phenolic and flavonoid contents, accompanied by a high antioxidant activity, and they revealed antimicrobial activity against four pathogens (S. enterica ser. Typhimurium, E. coli, L. monocytogenes and S. aureus). These results demonstrate the potential of these natural resources to be incorporated as bioactive preservatives in foods or their packaging.
Promising Preserving Agents from Sage and Basil: A Case Study with Yogurts
Authors: Ueda Jonata M. , Pedrosa Mariana C. , Fernandes Filipa A. , Rodrigues Paula , Melgar Bruno , Dias Maria Inês , Pinela José , Calhelha Ricardo C. , Ivanov Marija , Soković Marina , Heleno Sandrina A. , Carocho Márcio , Ineu Rafael P. , Ferreira Isabel C. F. R. , Barros Lillian
Published: March 2021

In the present work, sage (Salvia officinalis L.) and basil (Ocimum basilicum L.) were exploited for their preservative purposes, as viable alternatives to artificial ones. The ultrasound-assisted extraction (UAE) of bioactive compounds was pre-optimized using factorial screening analysis, prior to applying response surface methodology (RSM). The obtained extracts were characterized in terms of phenolic compounds by high-performance liquid chromatography coupled to photodiode array detector and mass spectrometer HPLC-DAD-ESI/MS and bioactivities, namely the antioxidant, antimicrobial and cytotoxic potential. In addition, the most promising extracts were incorporated into yogurts, that were further screened for nutritional and physico-chemical properties and microbial load, over a shelf life of 14 days. According to the obtained results, the solvent percentage is the most relevant factor for obtaining rosmarinic acid-rich extract, followed by the extraction time and ultrasonic power. For the antioxidant and antimicrobial activity, sage showed the best result for both analysis and none of the two plant extracts were hepatotoxic. Finally, both extracts did not show changes in the physicochemical and nutritional characteristics of the yogurts and did not interfere with the growth of lactic acid bacteria, an important microorganism during yogurt fermentation. These results highlight the high potential of sage and basil as natural preservatives.
Optimal Control Theory: Introduction to the Special Issue
Authors: Grigorieva Ellina
Published: March 2021

Optimal control theory is a modern extension of the classical calculus of variations [...]
The PARP Way to Epigenetic Changes
Authors: Ummarino Simone , Hausman Clinton , Di Ruscio Annalisa
Published: March 2021

ADP-ribosylation, is a reversible post-translational modification implicated in major biological functions. Poly ADP-ribose polymerases (PARP) are specialized enzymes that catalyze the addition of ADP ribose units from “nicotinamide adenine dinucleotide-donor molecules” to their target substrates. This reaction known as PARylation modulates essential cellular processes including DNA damage response, chromatin remodeling, DNA methylation and gene expression. Herein, we discuss emerging roles of PARP1 in chromatin remodeling and epigenetic regulation, focusing on its therapeutic implications for cancer treatment and beyond.
Introducing Uncertainty in Risk Calculation along Roads Using a Simple Stochastic Approach
Authors: Jaboyedoff Michel , Choanji Tiggi , Derron Marc-Henri , Fei Li , Gutierrez Amalia , Loiotine Lidia , Noel François , Sun Chunwei , Wyser Emmanuel , Wolff Charlotte
Published: March 2021

Based on a previous risk calculation study conducted along a road corridor, risk is recalculated using a stochastic simulation by introducing variability into most of the parameters in the risk equation. This leads to an exceedance curve comparable to those of catastrophe models. This approach introduces uncertainty into the risk calculation in a simple way, and it can be used for poorly documented cases to compensate for a lack of data. This approach tends to minimize risk or question risk calculations.
Hydrogen Emanations in Intracratonic Areas: New Guide Lines for Early Exploration Basin Screening
Authors: Moretti Isabelle , Brouilly Emyrose , Loiseau Keanu , Prinzhofer Alain , Deville Eric
Published: March 2021

Offshore the emissions of dihydrogen are highlighted by the smokers along the oceanic ridges. Onshore in situ measurements in ophiolitic contexts and in old cratons have also proven the existence of numerous H2 emissive areas. When H2 emanations affect the soils, small depressions and vegetation gaps are observed. These depressions, called fairy circles, have similarities with the pockmark and vent structures recognized for long time in the sea floor when natural gas escapes but also differences. In this paper we present a statistic approach of the density, size, and shape of the fairy circles in various basins. New data from Brazil and Australia are compared to the existing database already gathered in Russia, USA, and again Brazil. The comparison suggests that Australia could be one of the most promising areas for H2 exploration, de facto a couple of wells already found H2, whereas they were drilled to look for hydrocarbons. The sum of areas from where H2 is seeping overpasses 45 km2 in Kangaroo Island as in the Yorke Peninsula. The size of the emitting structures, expressed in average diameter, varies from few meters to kilometers and the footprint expressed in % of the ground within the structures varies from 1 to 17%. However, globally the sets of fairy circles in the various basins are rather similar and one may consider that their characteristics are homogeneous and may help to characterize these H2 emitting zones. Two kinds of size repartitions are observed, one with two maxima (25 m and between 220 m ± 25%) one with a simple Gaussian shape with a single maximum around 175 m ± 20%. Various geomorphological characteristics allow us to differentiate depressions of the ground due to gas emissions from karstic dolines. The more relevant ones are their slope and the ratio diameter vs. depth. At the opposite of the pockmark structures observed on the seafloor for which exclusion zones have been described, the H2 emitting structures may intersect and they often growth by coalescence. These H2 emitting structures are always observed, up to now, above Archean or Neoproterozoic cratons; it suggests that anoxia at the time the sedimentation and iron content play a key role in the H2 sourcing.
Promoting Emotional and Social Well-Being and a Sense of Belonging in Adolescents through Participation in Volunteering
Authors: Luque-Suárez Mónica , Olmos-Gómez María del Carmen , Castán-García María , Portillo-Sánchez Raquel
Published: March 2021

The aim of this study was to analyze the differences within education-related degrees with respect to participation in volunteering. Volunteering motivation promotes and encourages emotional and social well-being and a sense of belonging in university students. This study was based on a total sample of 985 students undertaking Degrees in Early Childhood Education, Primary Education, and Social Education who attended higher education institutions in Northern Africa (Spain) and Eastern Spain. Once the quality parameters of the instrument were determined, the reliability was confirmed, and data collection was initiated. In order to analyze the results, a multilevel study (ANOVA) was conducted by interacting the variables for degrees with three levels (PE = Primary Education; EC = Early Childhood Education; SE = Social Education) and the variable “volunteering is my motivation to feel better”, with five levels (strongly disagree, disagree, unsure, agree, and strongly agree). From the data obtained, it was concluded that there were significant differences between the different degree paths, the assessment covering sociodemographic variables and areas of interest showing that volunteering benefits university students both socially and in their decision-making processes.
Towards a Better Understanding of PTSD/Hypertension Associations: Examining Sociodemographic Aspects
Authors: Kibler Jeffrey L. , Ma Mindy
Published: March 2021

The present study is an examination of sociodemographic and environmental correlates of hypertension and post-traumatic stress disorder (PTSD), with the goal of better understanding previously identified PTSD and hypertension associations. Data from 5877 adults up to age 54 were analyzed to examine racial and ethnic differences in hypertension, and relationships of socioeconomic status (SES; total family income), employment status, and marital status, and urbanicity (urban, suburban, or rural habitation) with hypertension and PTSD. Next, a total model was tested to determine which sociodemographic and environmental variables, and/or PTSD were significant independent correlates of hypertension. Higher rates of hypertension were evident among African Americans (13.8%), relative to Caucasian (7.7%) or Hispanic (6.7%) participants (p < 0.001). Low SES (family income under USD 19,000) and unemployment were associated with significantly greater likelihood (p < 0.001) of hypertension (9.8% vs. 7.6% for low SES; 14.3% vs. 8.3% for unemployment) and PTSD (16.6% vs. 8.7% for low SES; 21.3% vs. 9.6% for unemployment). Participants who were married versus those separated or divorced were significantly less likely (p < 0.001) to have hypertension (9.0% vs. 11.9%) or PTSD (10.8% vs. 18.3%). Urbanicity was not significantly associated with hypertension or PTSD. Unemployment and PTSD were the only significant independent factors associated with hypertension.