bluuebunny/crossref_metadata_2025 huggingface dataset:
Resource Availability May Not Be a Useful Predictor of Migratory Bat Fatalities or Activity at Wind Turbines
Authors: Bennett Victoria J. , Hale Amanda M.
Published: June 2018

A better understanding of the ultimate mechanisms driving bat fatalities at wind turbines (i.e., the reason why bats are coming in close proximity to wind turbines) could inform more effective impact reduction strategies. One hypothesis is that bats come into close proximity to turbines due to existing resources (e.g., roosting sites) in the immediate area. Thus, if resource hotspots for bats could be identified in areas proposed for wind energy development, then fatalities could be reduced by siting turbines away from such hotspots. To explore this, we conducted a resource mapping exercise at a 48 km2 wind energy facility in north-central Texas. We mapped known resources (such as water sources, roosting sites, foraging sites, and commuting routes) for the 6 bat species present and compared resource availability with observed fatalities and acoustic activity. Although resource mapping identified concentrations of known resources for all species, it did not predict bat activity or fatalities. For example, Lasiurus cinereus and Lasiurus borealis comprised >90% of the fatalities, yet we found no positive relationship between resource availability and fatalities or acoustic activity for either species. Furthermore, up to 33% of these fatalities occurred at turbines without known resources within 200 m of the turbines, demonstrating that the fine-scale distribution of resources may not effectively inform turbine siting for these two migratory species. The challenge, therefore, remains to determine why bats during the migratory season are coming in close proximity with wind turbines.
Nonlinear Kinetics on Lattices Based on the Kinetic Interaction Principle
Authors: Kaniadakis Giorgio , Hristopulos Dionissios T.
Published: June 2018

Master equations define the dynamics that govern the time evolution of various physical processes on lattices. In the continuum limit, master equations lead to Fokker–Planck partial differential equations that represent the dynamics of physical systems in continuous spaces. Over the last few decades, nonlinear Fokker–Planck equations have become very popular in condensed matter physics and in statistical physics. Numerical solutions of these equations require the use of discretization schemes. However, the discrete evolution equation obtained by the discretization of a Fokker–Planck partial differential equation depends on the specific discretization scheme. In general, the discretized form is different from the master equation that has generated the respective Fokker–Planck equation in the continuum limit. Therefore, the knowledge of the master equation associated with a given Fokker–Planck equation is extremely important for the correct numerical integration of the latter, since it provides a unique, physically motivated discretization scheme. This paper shows that the Kinetic Interaction Principle (KIP) that governs the particle kinetics of many body systems, introduced in G. Kaniadakis, Physica A 296, 405 (2001), univocally defines a very simple master equation that in the continuum limit yields the nonlinear Fokker–Planck equation in its most general form.
Eco-Cognitive Computationalism: From Mimetic Minds to Morphology-Based Enhancement of Mimetic Bodies
Authors: Magnani Lorenzo
Published: June 2018

Eco-cognitive computationalism sees computation in context, exploiting the ideas developed in those projects that have originated the recent views on embodied, situated, and distributed cognition. Turing’s original intellectual perspective has already clearly depicted the evolutionary emergence in humans of information, meaning, and of the first rudimentary forms of cognition, as the result of a complex interplay and simultaneous coevolution, in time, of the states of brain/mind, body, and external environment. This cognitive process played a fundamental heuristic role in Turing’s invention of the universal logical computing machine. It is by extending this eco-cognitive perspective that we can see that the recent emphasis on the simplification of cognitive and motor tasks generated in organic agents by morphological aspects implies the construction of appropriate “mimetic bodies”, able to render the accompanied computation simpler, according to a general appeal to the “simplexity” of animal embodied cognition. I hope it will become clear that eco-cognitive computationalism does not aim at furnishing a final and stable definition of the concept of computation, such as a textbook or a different epistemological approach could provide: I intend to take into account the historical and dynamical character of the concept, to propose an intellectual framework that depicts how we can understand not only the change of its meaning, but also the “emergence” of new forms of computations.
Export-Led Growth, Global Integration, and the External Balance of Small Island Developing States
Authors: Kemp-Benedict Eric , Drakes Crystal , Laing Timothy J.
Published: June 2018

Small, open developing economies in general, and small island developing states (SIDS) in particular, have specific macroeconomic characteristics due both to their openness and their small size. Small size means they can never have fully independent capital-intensive domestic economies, so to raise incomes they must become thoroughly integrated into the global economy. The export sector thus becomes the engine of growth; it provides domestic income, which is spent on domestic goods and imports, driving overall economic output through a multiplier effect. Building on work within the Caribbean structuralist tradition, this paper presents a demand-driven model that includes capital accumulation and external debt. Given the limited data available for many small island states, the model explicitly represents the external macroeconomic balance. An aggregate representation of the national economy is derived formally from a two-sector model, following models of a petroleum exporting country developed Seers and Bruce and Girvan. The model’s performance was evaluated against the historical performance of the Caribbean countries of Barbados, Jamaica and Trinidad and Tobago.
Teaching Pre-Service Teachers How to Utilize Web 2.0 Platforms to Support the Educational Needs of Students with Disabilities in General Education Classrooms
Authors: Peterson-Ahmad Maria B. , Stepp Jennifer B. , Somerville Kyla
Published: June 2018

It is without question that technology in schools is here to stay. Educators have always been interested in the extent to which technology can be used to transform education and enhance student learning; however, the degree to which it is utilized in teacher preparation programs for pre-service teachers in terms of Web 2.0 use with future students is under debate. Web 2.0 use can be a particularly interesting tool for teachers to use in differentiating instructional strategies for students with disabilities in inclusive settings. Therefore, it is worthwhile for teacher preparation programs to look at how Web 2.0 platforms can further support students in special education in such settings. The following study delineates data from a study of N = 82 pre-service teachers. Throughout the course of this study, all students were administered a pre- and post-survey that asked questions specific to current knowledge of Web 2.0 and the extent to which they thought it could be used in their future teaching practices. In addition, all students completed an assignment within their respective courses that embedded a specific Web 2.0 component. This assignment required pre-service teacher candidates to utilize the Pinterest platform to find and ‘pin’ educational materials specific to students with whom they will work with in future inclusive classrooms, relative to the various categories of special education.
Phase Difference Measurement Method Based on Progressive Phase Shift
Authors: Zhang Min , Wang Hai , Qin Hongbo , Zhao Wei , Liu Yan
Published: June 2018

This paper proposes a method for phase difference measurement based on the principle of progressive phase shift (PPS). A phase difference measurement system based on PPS and implemented in the FPGA chip is proposed and tested. In the realized system, a fully programmable delay line (PDL) is constructed, which provides accurate and stable delay, benefitting from the feed-back structure of the control module. The control module calibrates the delay according to process, voltage and temperature (PVT) variations. Furthermore, a modified method based on double PPS is incorporated to improve the resolution. The obtained resolution is 25 ps. Moreover, to improve the resolution, the proposed method is implemented on the 20 nm Xilinx Kintex Ultrascale platform, and test results indicate that the obtained measurement error and clock synchronization error is within the range of ±5 ps.
Detectors on Edge Nodes against False Data Injection on Transmission Lines of Smart Grid
Authors: Xun Peng , Zhu Peidong , Zhang Zhenyu , Cui Pengshuai , Xiong Yinqiao
Published: June 2018

False data injection (FDI) attack is a hot topic in large-scale Cyber-Physical Systems (CPSs), which can cause bad state estimation of controllers. In this paper, we focus on FDI detection on transmission lines of the smart grid. We propose a novel and effective detection framework to identify FDI attacks. Different from the previous methods, there are multi-tier detectors which utilize edge nodes such as the programmable logic controllers (PLCs) instead of the central controller to detect attacks. The proposed framework can decrease the transmission time of data to reduce the latency of decisions because many sensory data need not be transmitted to the central controller for detection. We also develop a detection algorithm which utilizes classifiers based on machine learning to identify FDI. The training process is split from every edge node and is placed on the central node. The detectors are lightweight and are properly adopted in our detection framework. Our simulation experiments show that the proposed detection framework can provide better detection results than the existing detection approaches.
Lithium-Ion Battery Prognostics with Hybrid Gaussian Process Function Regression
Authors: Peng Yu , Hou Yandong , Song Yuchen , Pang Jingyue , Liu Datong
Published: June 2018

The accurate prognostics of lithium-ion battery state of health (SOH) and remaining useful life (RUL) have great significance for reducing the costs of maintenance. The methods based on the physical models cannot perform satisfactorily as the systems become more and more complex. With the development of digital acquisition and storage technology, the data of battery cells can be obtained. This makes the data-driven methods get more and more attention. In this paper, to overcome the problem that the trend fitting deteriorates rapidly when test data are far from the training data for multiple-step-ahead estimation, a prognostic method fusing the wavelet de-noising (WD) method and the hybrid Gaussian process function regression (HGPFR) model for predicting the RUL of the lithium-ion battery is proposed. Gaussian process regression (GPR) is a typical representative for the Bayesian structure with non-parameter expression and uncertainty presentation. In this case, the effects on predictive results are compared and analyzed using the proposed method and the HGPFR model with different lengths of training data. Besides, in consideration of the degradation characteristics for the lithium-ion battery data set, the selections of the wavelet de-noising method are performed with corresponding experimental analyses. Furthermore, we set the hype-parameter for the mean function and co-variance function, and then develop a method for parameter optimization to make the proposed model suitable for the data. Moreover, a numerical simulation based on the data repository of Department of Engineering Science (DES) university of Oxford and Center for Advanced Life Cycle Engineering (CALCE) of University of Maryland is carried out, and the results are analyzed. For the data repository, an accuracy of 2.2% is obtained compared with the same value of 6.7% for the HGPFR model. What is more, the applicability and stability are verified with the prognostic results by the proposed method.
Capacitive Emulation Using Predictive Current Control in LCL-Filtered Grid-Connected Converters to Mitigate Grid Current Distortion
Authors: Espi Jose Miguel , Castello Jaime
Published: June 2018

This paper presents an improvement of the capacitive emulation (CE) method to reduce the line current distortion caused by grid-tied LCL-filtered converters. In these cases, the grid voltage is applied to the LCL’s capacitor, which generates a distorted capacitor current that pollutes the line. The CE method consists in controlling the converter currents instead of the grid currents, while the converter generates a copy of the distorted capacitor current, so that both the copy and the distorted currents cancel each other in the grid. Therefore, we can say that the converter emulates a negative capacitance connected to the grid, while at the same time delivers its active and reactive powers at the fundamental frequency. The CE method is achieved by adding an estimation of the distorted capacitor current to the converter current reference. However, an effective capacitive emulation requires a current control capable of accurately tracking all harmonics added to the current reference. In this sense, this paper proposes the use of a new integral predictive current control (IPCC), a dead-beat type of control that ensures a constant closed-loop group delay in a wide bandwidth. Unlike a PI control where the closed-loop delay varies with the frequency of the tracked harmonic, the constant control delay of the IPCC can be effectively compensated with a buffer-based advanced current reference. The effectiveness of the proposed CE method with IPCC control to reduce the total harmonic distortion (THD) of the line currents has been proved experimentally on a 10 kVA transformerless grid-connected three-phase inverter.
Area-Saving and High-Efficiency RGB LED Driver with Adaptive Driving Voltage and Energy-Saving Technique
Authors: Hsu Yi-Chieh , Lin Jing-Yuan , Chen Charlie Chung-Ping
Published: June 2018

The red-green-blue light-emitting diode (RGBLED) driver with adaptive driving voltage and energy-saving (ADVE) technique is presented in this paper. To obtain the proper driving voltage, a dynamic output voltage selector is proposed. This approach tracks the reference voltage of a boost converter to achieve the appropriate output voltage of the boost converter. Hence, the power loss of the linear current regulator is reduced to improve the efficiency of whole system. Moreover, the chip area is saved by the proposed switching linear current regulator. This chip was fabricated using TSMC 0.35 μm 2P4M complementary metal-oxide-semiconductor (CMOS) technology. The active chip area is 0.3 mm2. The maximum driving current and operating frequency are 100 mA and 100 kHz, respectively. Compared with a conventional LED driver with fixed output voltage, the experimental results demonstrate that the power loss of the proposed LED driver with ADVE technique is reduced by over 58%.
Quantitative Resilience Assessment under a Tri-Stage Framework for Power Systems
Authors: Zhang Han , Yuan Hanjie , Li Gengfeng , Lin Yanling
Published: June 2018

The frequent occurrence of natural disasters and malicious attacks has exerted unprecedented disturbances on power systems, accounting for the extensive attention paid to power system resilience. Combined with the evolving nature of general disasters, this paper proposes resilience assessment approaches for power systems under a tri-stage framework. The pre-disaster toughness is proposed to quantify the robustness of power systems against potential disasters, where the thinking of area division and partitioned multi-objective risk method (PMRM) is introduced. In the case of information deficiency caused by disasters, the during-disaster resistance to disturbance is calculated to reflect the real-time system running state by state estimation (SE). The post-disaster restoration ability consists of response ability, restoration efficiency and restoration economy, which is evaluated by Sequential Monte-Carlo Simulation to simulate the system restoration process. Further, a synthetic metric system is presented to quantify the resilience performance of power systems from the above three aspects. The proposed approaches and framework are validated on the IEEE RTS 79 system, and helpful conclusions are drawn from extensive case studies.
Dual Enhancement of Power System Monitoring: Improved Probabilistic Multi-Stage PMU Placement with an Increased Search Space & Mathematical Linear Expansion to Consider Zero-Injection Bus
Authors: Ali Ziad M. , Razavi Seyed-Ehsan , Javadi Mohammad Sadegh , Gandoman Foad H. , Abdel Aleem Shady H.E.
Published: June 2018

This paper presents a mathematical linear expansion model for the probabilistic Multistage Phasor Measurement Unit (PMU) Placement (MPP) in which zero-injection buses (ZIBs), as well as communication channel limitations, are taken into consideration. From the linearization perspective, presenting a model formulizing the probabilistic concept of observability while modelling the ZIB is of great significance, and has been done in this paper for the first time. More importantly, the proposed probabilistic MPP utilizes a technique disregarding the prevalent subsidiary optimizations for each planning stage. Although this technique, in turn, increases the problem complexity with manifold variables, it guarantees the global optimal solution in a wider and thorough search space; while in the prevalent methods, some parts of the search space might be missed. Furthermore, the proposed model indicates more realistic aspects of the MPP where system operators are allowed to follow their intention about the importance of buses such as strategic ones based on monitoring the priority principles. In addition, the model is capable of considering the network topology changes due to long-term expansions over the planning horizon. Finally, in order to demonstrate the effectiveness of the proposed formulation, the model is conducted on the IEEE 57-bus standard test system and the large scale 2383-bus Polish power system.
Sealing Failure Analysis on V-Shaped Sealing Rings of an Inserted Sealing Tool Used for Multistage Fracturing Processes
Authors: Hu Gang , Wang Guorong , Dai Liming , Zhang Peng , Li Ming , Fu Yukun
Published: June 2018

The inserted sealing tool is a critical downhole implement that is used to balance the downhole pressure in multistage fracturing operations and prevent fracturing fluid from overflow and/or backward flow. The sealing ring of an inserted sealing tool plays an important role in downhole sealing since a sealing failure would ail the fracturing operation. In order to improve the sealing performance and reduce the potential fracturing failures, this research aims to investigate the influence of V-shaped sealing ring geometries on sealing performance. Constitutive experiments of rubber materials were carried out and the parameters of the constitutive relationship of rubber materials were obtained. A two-dimensional axisymmetric model considering the sealing ring has been established and influences are investigated with considerations of various system parameters and operating conditions. It is found that the stresses concentrated at the shoulder and inner vertex of the sealing ring have direct impact on the damage of the sealing rings under operational conditions. Moreover, the sealing interference, among several other factors, greatly affects the life of the sealing ring. A new design of the sealing ring is suggested with optimized geometric parameters. Its geometric parameters are the edge height of 5 mm, the vertex angle of 90°–100°, and the interference of 0.1 mm, which show a better performance and prolonged operation life of the sealing ring.
Numerical Study on the Transient Thermal Performance of a Two-Phase Closed Thermosyphon
Authors: Zhao Zhongchao , Zhang Yong , Zhang Yanrui , Zhou Yimeng , Hu Hao
Published: June 2018

The transient thermal performance of phase change and heat and mass transfer in a two-phase closed thermosyphon are studied with computational fluid dynamics (CFD). A CFD model based on the volume of fluid technique is built. Deionized water is specified as the working fluid of this thermosyphon. The CFD model reproduces evaporation and condensation in the thermosyphon at different heating inputs. The average wall temperatures are also analyzed. Variations of average wall temperatures indicate that this thermosyphon reaches a steady state after 19 s, and starts to work in advance when the heating input increases. Moreover, thermal resistance is decreased until a minimum (0.552 K/W) by increasing the heating input, and the effective thermal conductivity is elevated to a maximum (2.07 × 106 W/m∙K).
Thermodynamic, Economic and Environmental Evaluation of an Improved Ventilation Air Methane-Based Hot Air Power Cycle Integrated with a De-Carbonization Oxy-Coal Combustion Power Plant
Authors: Xu Cheng , Gao Yachi , Zhang Qiang , Zhang Guoqiang , Xu Gang
Published: June 2018

Efficient utilization of ventilation air methane (VAM) as well as improving the energy efficiency of de-carbonization oxy-coal combustion power plants are intensively studied for achieving energy savings and greenhouse gas (GHG) emission control. Here, an improved VAM-coal hybrid power generation system, which integrates a VAM-based hot air power cycle with a de-carbonization oxy-coal combustion circulating fluid bed (CFB) power plant was proposed. In the proposed system, part of the boiler flue gas was bypassed to feed the VAM auto-oxidation, and the whole VAM oxidation heat was efficiently utilized to drive a hot air power cycle. Meanwhile, the turbine exhaust air was utilized to heat the feed/condensed water within the regenerative heating trains in a cascade way, which was in turn beneficial to de-carbonization oxy-coal combustion plant. The mass and energy balance of the proposed system were determined using the simulation process. The thermodynamic benefits, economic viability and the environmental impacts were discussed. Results showed that energy efficiency of the proposed system reached 27.1% with the energy saving ratio at 0.9%. The cost of electricity (COE) was $118.15/MWh with the specific CO2 emission as low as 17.46 kg CO2/MWh.
Optimization of Inventory Routing Problem in Refined Oil Logistics with the Perspective of Carbon Tax
Authors: Wang Songyi , Tao Fengming , Shi Yuhe
Published: June 2018

In order to solve the optimization problem of the refined oil distribution system from the perspectives of low-carbon and environmental protection, this paper focuses on the characteristics of the secondary distribution of refined oil and combines it with the integrated optimization concept of refined oil distribution network, where a low-carbon inventory routing problem (LCIRP) model is constructed with the minimum total costs as the objective function on the basis of considering carbon emissions. An adaptive genetic algorithm combined with greedy algorithm is designed to solve the model, and an example is given to verify the effectiveness of the algorithm. Then, this paper solves the model with two parts by introducing a practical numerical example: in the first part, the LCIRP models with different carbon tax values are solved, which verifies the effectiveness of the model and proves that carbon tax policies can effectively reduce the carbon emissions in the secondary distribution network of refined oil; in the second part, the LCIRP models with the different maximum load capacity of oil tank trucks are solved, which provides the economic and environmentally friendly distribution schemes for refined oil distribution enterprises under the premise of carbon tax policies and load limitation. Finally, the emission reduction proposals that take into account both economic and environmental benefits are given respectively from the aspect of government environmental protection agencies and from the aspect of refined oil distribution enterprises.
Power and Capacity Consensus Tracking of Distributed Battery Storage Systems in Modular Microgrids
Authors: Zhang Xianyong , Huang Yaohong , Li Li , Yeh Wei-Chang
Published: June 2018

Conventional microgrids have a specific system configuration and a complex hierarchical control structure, which has resulted in difficulties in their economic development. A modular microgrid based on distributed battery storage has been proposed to realize the rapid economic development of small-to-medium microgrids. Control of modular microgrids is simplified to voltage control within modules and exchange power control among modules. Battery power has great influence on battery performance. Space-time complementary power characteristics among modules help to alleviate power fluctuations, prolong the service life and realize the unified maintenance of distributed batteries. Leader-following consensus theory of multi-agent systems is adopted to realize the power and capacity consensus tracking of distributed battery storage in a modular microgrid. Sufficient and necessary conditions for continuous-time and sampled-data bounded power and capacity consensus tracking of distributed battery storages are deduced by a matrix analytical method. Steady regions of sampling period and sampling delay for sampled-data bounded power and capacity consensus tracking are determined by analytical or numerical solutions. Simulations and experiments on a modular microgrid demonstration project located on DongAo Island (China) show the effectiveness and robustness of the proposed power and capacity consensus tracking strategy for distributed storage systems. The power and capacity consensus tracking strategy determines the exchange power among modules and improves the control technology of modular microgrids.
Interaction of Wind Turbine Wakes under Various Atmospheric Conditions
Authors: Lee Sang , Vorobieff Peter , Poroseva Svetlana
Published: June 2018

We present a numerical study of two utility-scale 5-MW turbines separated by seven rotor diameters. The effects of the atmospheric boundary layer flow on the turbine performance were assessed using large-eddy simulations. We found that the surface roughness and the atmospheric stability states had a profound effect on the wake diffusion and the Reynolds stresses. In the upstream turbine case, high surface roughness increased the wind shear, accelerating the decay of the wake deficit and increasing the Reynolds stresses. Similarly, atmospheric instabilities significantly expedited the wake decay and the Reynolds stress increase due to updrafts of the thermal plumes. The turbulence from the upstream boundary layer flow combined with the turbine wake yielded higher Reynolds stresses for the downwind turbine, especially in the streamwise component. For the downstream turbine, diffusion of the wake deficits and the sharp peaks in the Reynolds stresses showed faster decay than the upwind case due to higher levels of turbulence. This provides a physical explanation for how turbine arrays or wind farms can operate more efficiently under unstable atmospheric conditions, as it is based on measurements collected in the field.
Feedback-Oriented Intelligent Monitoring of a Storage-Based Solar Photovoltaic (PV)-Powered Microgrid with Mesh Networks
Authors: Almadhor Ahmad
Published: June 2018

This paper proposes a mesh network-based communication architecture that can be used to monitor and control different elements in a microgrid. A solar Photovoltaic (PV) and storage-based, off-grid, microgrid model is designed using MATLAB Simulink. The communication mechanism between every element of the microgrid is also represented and simulated in the model developed. Basic features of monitoring and regulating the generation, and demand-side of the grid are discussed along with feedback-based measures for effective performance monitoring in the microgrid. Finally, the paper also points out a unique cloud infrastructure that can be used to store data, perform data analysis and assist in decision making in case of extreme situations. Overall, this paper proposes a simple feedback based mechanism for proactive monitoring of PV generation in a microgrid using a communication architecture powered by mesh networks.
Impact of Demand Response Programs on Optimal Operation of Multi-Microgrid System
Authors: Nguyen Anh-Duc , Bui Van-Hai , Hussain Akhtar , Nguyen Duc-Huy , Kim Hak-Man
Published: June 2018

The increased penetration of renewables is beneficial for power systems but it poses several challenges, i.e., uncertainty in power supply, power quality issues, and other technical problems. Backup generators or storage system have been proposed to solve this problem but there are limitations remaining due to high installation and maintenance cost. Furthermore, peak load is also an issue in the power distribution system. Due to the adjustable characteristics of loads, strategies on demand side such as demand response (DR) are more appropriate in order to deal with these challenges. Therefore, this paper studies how DR programs influence the operation of the multi-microgrid (MMG). The implementation is executed based on a hierarchical energy management system (HiEMS) including microgrid EMSs (MG-EMSs) responsible for local optimization in each MG and community EMS (C-EMS) responsible for community optimization in the MMG. Mixed integer linear programming (MILP)-based mathematical models are built for MMG optimal operation. Five scenarios consisting of single DR programs and DR groups are tested in an MMG test system to evaluate their impact on MMG operation. Among the five scenarios, some DR programs apply curtailing strategies, resulting in a study about the influence of base load value and curtailable load percentage on the amount of curtailed load and shifted load as well as the operation cost of the MMG. Furthermore, the impact of DR programs on the amount of external and internal trading power in the MMG is also examined. In summary, each individual DR program or group could be handy in certain situations depending on the interest of the MMG such as external trading, self-sufficiency or operation cost minimization.
Comments to Paper Entitled: Development of a Data-Driven Predictive Model of Supply Air Temperature in an Air-Handling Unit for Conserving Energy. Energies 2018, 11, 407
Authors: Lin Yaolin , Yang Wei
Published: June 2018

I have read, with interest, the article authorized by Hong and Kim, which was published in Energies 2018, 11, 407; doi:10.3390/en11020407: entitled “Development of a Data-Driven Predictive Model of Supply Air Temperature in an Air-Handling Unit for Conserving Energy”[...]
Characterization of Landfill Leachates and Sediments in Major Cities of Indochina Peninsular Countries—Heavy Metal Partitioning in Municipal Solid Waste Leachate
Authors: Xaypanya Phetyasone , Takemura Jiro , Chiemchaisri Chart , Seingheng Hul , Tanchuling Maria
Published: June 2018

In this study, leachate and sediment samples were collected from the leachate drains, ponds and waste pits of three landfills in the Indochina peninsula to investigate the level of contamination of biochemical parameters, especially heavy metals. In-situ and laboratory measurements were conducted, together with site surveys to discuss the effects of site characteristics on leachate qualities. It was confirmed from the investigation that the changes in leachate qualities are mainly caused by the landfill site conditions, e.g., soil cover, the waste compaction level, waste thickness, dumping method, and leachate storage, and that these conditions lead to different levels of dilution and biochemical reaction of the leachate. Most of the biochemical parameters of the fresh leachates were greater than the effluent standards, and showed higher concentrations than those measured for the leachate in large storage ponds. The concentrations of the parameters were higher in the dry season than the wet season for all fresh leachate samples, but no significant seasonal difference was observed in the large leachate storage ponds. The majority of heavy metals were partitioned in the suspended solids, and no clear seasonal change of heavy metal contents was contained in the suspended solids and sediment samples.
Linking Marine Ecosystem Services to the North Sea’s Energy Fields in Transnational Marine Spatial Planning
Authors: Vogel Christina , Ripken Malena , Klenke Thomas
Published: June 2018

Marine spatial planning temporally and spatially allocates marine resources to different users. The ecosystem approach aims at optimising the social and economic benefits people derive from marine resources while preserving the ecosystem’s health. Marine ecosystem services are defined as the benefits people obtain from marine ecosystems. The aim of this study is to determine which interrelations between marine ecosystem services and the marine energy industry can be identified for use in transnational marine spatial planning exemplified in the North Sea region. As the North Sea is one of the busiest seas worldwide, the risk of impairing the ecosystems through anthropogenic pressures is high. Drawing on a literature-based review, 23 marine ecosystem services provided by the North Sea region were defined and linked to seven offshore energy fields comprising oil and natural gas, wind, tides and currents, waves, salinity gradients, algal biomass, and geothermal heat. The interactions were divided into four categories: dependence, impact, bidirectional, or no interaction. Oil and natural gas, as well as algae biomass, are the fields with the most relations with marine ecosystem services while waves and salinity gradients exhibit the least. Some marine ecosystem services (Conditions for Infrastructure, Regulation of Water Flows, and Cognitive Development) are needed for all fields; Recreation and Tourism, Aesthetic and Cultural Perceptions and Traditions, Cognitive Development, and Sea Scape are impacted by all fields. The results of this research provide an improved basis for an ecosystem approach in transnational marine spatial planning.
Permafrost Regime Affects the Nutritional Status and Productivity of Larches in Central Siberia
Authors: Prokushkin Anatoly S. , Hagedorn Frank , Pokrovsky Oleg S. , Viers Jerome , Kirdyanov Alexander V. , Masyagina Oxana V. , Prokushkina Marina P. , McDowell William H.
Published: June 2018

Permafrost exerts strong controls on forest development through nutrient availability. The key question of this study was to assess the effect of site conditions on macroelement concentration and stable isotope (δ13C and δ15N) dynamics during the growing season, and nutrient stoichiometry and resorption efficiency in the foliage of two common larch species in Siberia. Foliar nutrient (N, P and K) concentrations of larches grown on permafrost soils were exceptionally high in juvenile needles compared to those from a permafrost-free region (+50% and 130% for P and K), but were two-fold lower at needle maturation. Within permafrost terrain trees, sites with a warmer and deeper soil active layer had 15–60% greater nutrient concentrations and higher δ15N in their needles compared to shallower, colder soils. Larch of permafrost-free sites demonstrated an enrichment of foliage in 15N (+1.4% to +2.4‰) in comparison to permafrost terrain (−2.0% to −6.9‰). At all sites, foliar δ13C decreased from June to August, which very likely results from an increasing contribution of current photoassimilates to build foliar biomass. With senescence, nutrient concentrations in larch needles decreased significantly by 60–90%. This strong ability of larch to retain nutrients through resorption is the essential mechanism that maintains tree growth early in the growing season when soil remains frozen. The high resorptive efficiency found for K and P for larches established on permafrost suggests nutrient limitation of tree growth within the Central Siberian Plateau not only by N, as previously reported, but also by P and K. The increasing nutrient concentrations and a 15N enrichment of foliage towards warmer sites was paralleled by an up to 50-fold increase in biomass production, strongly suggesting that accelerated nutrient cycling with permafrost degradation contributes to an increased productivity of Siberian larch forests.
Comparative Transcriptomics Analysis of Phytohormone-Related Genes and Alternative Splicing Events Related to Witches’ Broom in Paulownia
Authors: Dong Yanpeng , Zhang Huiyuan , Fan Guoqiang , Zhai Xiaoqiao , Wang Zhe , Cao Yabing
Published: June 2018

Paulownia is a native fast-growing tree in China that has been introduced into many countries. However, it is often infected by Paulownia witches’ broom (PaWB) disease, which can lead to large declines in yield. PaWB is caused by a phytoplasma that is an obligate biotrophic plant pathogen. Until now, the molecular mechanisms of interactions between the host plants and the phytoplasma have not been clear. In previous studies, it was reported that PaWB-infected Paulownia exhibited healthy morphology after being treated with methyl methane sulfonate (MMS) at the concentration of 20 mg·L−1 (for Paulownia tomentosa (PT) and Paulownia fortunei (PF) or 15 mg·L−1 (for P. tomentosa × P. fortunei) MMS. In this study, the whole transcriptome expression profile of PaWB-infected Paulownia was studied using high-throughput sequencing technology. In total, 74 significantly differentially expressed genes were detected among three species of healthy, PaWB-infected Paulownia, and the Paulownia treated with MMS. We identified and analyzed genes related to the roles of phytohormones and alternative splicing events involved in regulating plant growth. In response to phytoplasma infection, the concentrations of the plants’ phytohormones were altered, leading to morphology transformation. This research will provide valuable information to detect the molecular mechanisms involved in the Paulownia response to phytoplasma infection.
Effects of Drought and Salinity on European Larch (Larix decidua Mill.) Seedlings
Authors: Plesa Ioana M. , González-Orenga Sara , Al Hassan Mohamad , Sestras Adriana F. , Vicente Oscar , Prohens Jaime , Sestras Radu E. , Boscaiu Monica
Published: June 2018

Larix decidua, the European larch, is not normally affected by drought or salinity in its natural habitats, but it may be when grown as an ornamental tree, by the widespread practice of winter de-icing of mountain roads with NaCl, and because of global warming-induced environmental changes. The responses of two-month-old larch seedlings to 30 days water deficit (withholding irrigation) or salt stress (150 mM NaCl) treatments were studied by determining stress-induced changes in several growth parameters and biochemical markers (ion and osmolyte contents, level of oxidative stress, activation of enzymatic and non-enzymatic antioxidant systems). Both treatments caused the inhibition of growth, degradation of photosynthetic pigments, a small increase in malondialdehyde (MDA, an oxidative stress biomarker), and the activation of antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR). In all cases, salinity appeared to have stronger effects on the seedlings than water deficit. The presence of relatively high concentrations of glycine betaine, both in control and stressed plants, may represent a constitutive mechanism of defence against stress in European larch. Additionally, other responses were specific for salt stress and included the activation of K+ transport from roots to shoots and the accumulation of Pro as an osmoprotectant.
Response of Black Ash Wetland Gaseous Soil Carbon Fluxes to a Simulated Emerald Ash Borer Infestation
Authors: Van Grinsven Matthew , Shannon Joseph , Bolton Nicholas , Davis Joshua , Noh Nam Jin , Wagenbrenner Joseph , Kolka Randall , Pypker Thomas
Published: June 2018

The rapid and extensive expansion of emerald ash borer (EAB) in North America since 2002 may eliminate most existing ash stands, likely affecting critical ecosystem services associated with water and carbon cycling. To our knowledge, no studies have evaluated the coupled response of black ash (Fraxinus nigra Marsh.) wetland water tables, soil temperatures, and soil gas fluxes to an EAB infestation. Water table position, soil temperature, and soil CO2 and CH4 fluxes were monitored in nine depressional headwater black ash wetlands in northern Michigan. An EAB disturbance was simulated by girdling (girdle) or felling (ash-cut) all black ash trees with diameters greater than 2.5 cm within treated wetlands (n = 3 per treatment). Soil gas fluxes were sensitive to water table position, temperature, and disturbance. Soil CO2 fluxes were significantly higher, and high soil CH4 fluxes occurred more frequently in disturbed sites. Soil CH4 fluxes in ash-cut were marginally significantly higher than girdle during post-treatment, yet both were similar to control sites. The strong connection between depressional black ash wetland study sites and groundwater likely buffered the magnitude of disturbance-related impact on water tables and carbon cycling.
Development of Somatic Embryo Maturation and Growing Techniques of Norway Spruce Emblings towards Large-Scale Field Testing
Authors: Tikkinen Mikko , Varis Saila , Aronen Tuija
Published: June 2018

The possibility to utilize non-additive genetic gain in planting stock has increased the interest towards vegetative propagation. In Finland, the increased planting of Norway spruce combined with fluctuant seed yields has resulted in shortages of improved regeneration material. Somatic embryogenesis is an attractive method to rapidly facilitate breeding results, not in the least, because juvenile propagation material can be cryostored for decades. Further development of technology for the somatic embryogenesis of Norway spruce is essential, as the high cost of somatic embryo plants (emblings) limits deployment. We examined the effects of maturation media varying in abscisic acid (20, 30 or 60 µM) and polyethylene glycol 4000 (PEG) concentrations, as well as the effect of cryopreservation cycles on embryo production, and the effects of two growing techniques on embling survival and growth. Embryo production and nursery performance of 712 genotypes from 12 full-sib families were evaluated. Most embryos per gram of fresh embryogenic mass (296 ± 31) were obtained by using 30 µM abscisic acid without PEG in the maturation media. Transplanting the emblings into nursery after one-week in vitro germination resulted in 77% survival and the tallest emblings after the first growing season. Genotypes with good production properties were found in all families.
The Transcriptomic Responses of Pinus massoniana to Drought Stress
Authors: Du Mingfeng , Ding Guijie , Cai Qiong
Published: June 2018

Masson pine (Pinus massoniana) is a major fast-growing timber species planted in southern China, a region of seasonal drought. Using a drought-tolerance genotype of Masson pine, we conducted large-scale transcriptome sequencing using Illumina technology. This work aimed to evaluate the transcriptomic responses of Masson pine to different levels of drought stress. First, 3397, 1695 and 1550 unigenes with differential expression were identified by comparing plants subjected to light, moderate or severe drought with control plants. Second, several gene ontology (GO) categories (oxidation-reduction and metabolism) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways (plant hormone signal transduction and metabolic pathways) were enriched, indicating that the expression levels of some genes in these enriched GO terms and pathways were altered under drought stress. Third, several transcription factors (TFs) associated with circadian rhythms (HY5 and LHY), signal transduction (ERF), and defense responses (WRKY) were identified, and these TFs may play key roles in adapting to drought stress. Drought also caused significant changes in the expression of certain functional genes linked to osmotic adjustment (P5CS), abscisic acid (ABA) responses (NCED, PYL, PP2C and SnRK), and reactive oxygen species (ROS) scavenging (GPX, GST and GSR). These transcriptomic results provide insight into the molecular mechanisms of drought stress adaptation in Masson pine.
Development and Validation of a Simulation Model for the Temperature Field during High-Frequency Heating of Wood
Authors: Chai Haojie , Zhao Jingyao , Cai Yingchun
Published: June 2018

In the process of applying high-frequency heating technology to wood drying, controlling the material temperature affects both drying speed and drying quality. Therefore, research on the heat transfer mechanism of high-frequency heating of wood is of great significance. To study the heat transfer mechanism of high-frequency heating, the finite element method was used to establish and solve the wood high-frequency heating model, and experimental verification was carried out. With a decrease in moisture content, the heating rate decreased, then increased, and then decreased again. There was no obvious linear relationship between the moisture content and heating rate; the simulation accuracy of the heating rate was higher in the early and later drying stages and slightly lower near the fiber saturation point. For the central section temperature distribution, the simulation and actual measurement results matched poorly in the early drying stage because the model did not fully consider the differences in the moisture content distribution of the actual test materials. In the later drying stage, the moisture content distribution of the test materials became uniform, which was consistent with the model assumptions. Considering the changes in heating rate and temperature distribution, the accuracy of the model is good under the fiber saturation point, and it can be used to predict the high-frequency heating process of wood.
Conventional and Non-Conventional Yeasts in Beer Production
Authors: Capece Angela , Romaniello Rossana , Siesto Gabriella , Romano Patrizia
Published: June 2018

The quality of beer relies on the activity of fermenting yeasts, not only for their good fermentation yield-efficiency, but also for their influence on beer aroma, since most of the aromatic compounds are intermediate metabolites and by-products of yeast metabolism. Beer production is a traditional process, in which Saccharomyces is the sole microbial component, and any deviation is considered a flaw. However, nowadays the brewing sector is faced with an increasing demand for innovative products, and it is diffusing the use of uncharacterized autochthonous starter cultures, spontaneous fermentation, or non-Saccharomyces starters, which leads to the production of distinctive and unusual products. Attempts to obtain products with more complex sensory characteristics have led one to prospect for non-conventional yeasts, i.e., non-Saccharomyces yeasts. These generally are characterized by low fermentation yields and are more sensitive to ethanol stress, but they provide a distinctive aroma and flavor. Furthermore, non-conventional yeasts can be used for the production of low-alcohol/non-alcoholic and light beers. This review aims to present the main findings about the role of traditional and non-conventional yeasts in brewing, demonstrating the wide choice of available yeasts, which represents a new biotechnological approach with which to target the characteristics of beer and to produce different or even totally new beer styles.