bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of power system for UAV ground control station in Natuna Island
Authors: Putri Utami Dannya Maharani , Setiawan Eko Adhi 
Published: December 2022

Abstract
The Unmanned Aerial Vehicle (UAV) is controlled remotely by the operator at the Ground Control Station (GCS) during the mission. Reliable electrical energy is needed to supply energy needs in GCS, such as radio communications, workstations, weather stations, HVAC systems, and lamps when the UAV is operating. GCS is located in Ranai City, Natuna Islands. The UAV mission in Ranai can assist the military in monitoring border surveillance, disaster management, and mapping the area. GCS power source in the initial design, using a diesel generator as the main power source with a power of 12 kW for 192.3 kWh per day energy consumption and 10.8 kW load peak. This paper has shown the study on a hybrid system with 3 scenarios, consisting of a PV system, wind turbine, generator, and battery. The system is simulated by using HOMER for accounting the technical and economic aspects. The results showed that the NPC and LCOE of the third scenario, which consisted of PV/wind/battery, were $181,157.38 and $0.15 per kWh, respectively. It has the lowest cost compared to the first scenario with the usage of diesel generator only. The average fuel consumption is 7.97 litre per day, down 87% compared to the existing condition. Thus, this configuration can overcome the costs of delivering fuel supplies for GCS operations and complement the government’s efforts to achieve emission reduction targets.
Numerical Analysis on Hydrodynamical Performance of Twin Half-rotating Impeller Tidal Turbine
Authors: Sun C K , Wang X Y , Zhang X C , Xu X R , Zhang Y H 
Published: December 2022

Abstract
To improve the utilization rate of tidal current energy, Twin Half-rotating Impeller Tidal Turbine(THITT), a new type of tidal turbine was proposed based on the half-rotating impeller(HRI) which was a new type lift-resistance compound impeller, and its virtual prototype was established. By changing the way the impeller rotated, two kinds of CFD models were established and taken into Xflow to calculate. The differences in their velocity fields and hydrodynamical performance were compared. The results demonstrated that THITT of different rotating directions both own good start-up performance and there were no dead points. Compared with the output power of the two independent impellers, the output power was increased by 20% when rotating in the spin.
Investigation of the Impact Bioethanol Blends into Biodiesel on Combustion Characteristics, Engine Performance, and Emissions of Diesel Engine
Authors: Kanokkhanarat Phobkrit , Depaiwa Nattawoot , Karin Preechar , Wongpattharaworakul Veerayut , Srisurangkul Chadchai , Yamakita Masaki 
Published: December 2022

Abstract
Emissions from a diesel engine are dangerous to the environment and human health. Substitutable fuels from a renewable source are one of the alternatives to reduce emissions. Neat biodiesel from based palm oil (B100) can reduce emissions from higher oxygen content to be more complete combustion. The disadvantage of neat biodiesel is lower thermal efficiency from an advancement ignition. To improve this problem, adding bioethanol produced from agriculture products into neat biodiesel by weight ratio as B100E5 (95% B100 with 5% bioethanol) and B100E10 (90% B100 with 10% bioethanol). Hence, the focus of this research is to examine the combustion and emission characteristics, including engine performance, of bioethanol blends into neat biodiesel fuels (B100E5 and B100E10) compared with neat biodiesel (B100). All samples were tested at an engine load of 140 NM with constant engine speeds of 1000, 1500, and 2000 RPM on a diesel engine. The results of bioethanol blends into biodiesel fuels indicate that the pressure in the combustion cylinder and rate of heat release increase with increasing percentages of bioethanol. B100E10 shows the highest brake thermal efficiency. The smoke intensity of bioethanol blends into biodiesel fuels is reduced by more than 50% when compared to neat biodiesel fuel, and higher NOx emission from higher oxygen content in the fuels.
Reduction of Diesel Engine’s Particulate Matters using Retrofit CeO2 Diesel Oxidative Catalyst and Partial Flow Diesel Particulate Filter System
Authors: Liu Hai , Charoenphonphanich Chinda , Karin Preechar , Srilomsak Mek , Srimanosaowapak Sompong , Hanamura Katsunori 
Published: December 2022

Abstract
In this research, CeO2 was chosen for the DOC catalyst. Moreover, a partial-flow DPF was installed after DOC. The exhaust gas experiment was conducted at 20% - 50% engine load varying 1000,1500, and 2000 rpm of engine speed. The research results show that NOx reduced around 25% with CeO2 DOC and DPF systems at higher engine load. On the other hand, particulate matters decrease around 65% after CeO2 DOC and DPF systems. Furthermore, CO and HC amount were substantially reduced after applying after-treatment systems. According to fuel consumption, BSFC, and BTE results, the after-treatment system has no significant impact on engine performance.
20 years (2001-2020) of GIS-based forest cover loss in the Natura 2000 sites of Dobruja Region, Romania
Authors: Albulescu Andra-Cosmina , Larion Daniela 
Published: December 2022

Abstract
Forests are among the most valued, yet the most threatened biomes in the world; their management being a key issue of sustainability, as illustrated by the 15th Sustainable Development Goal (Life on Earth) set for 2030. In order to sustainably manage the forest ecosystems located in areas that were designated for nature protection and restoration – like the Natura 2000 (N2k) sites, knowledge related to forest cover loss is of interest, as it offers valuable clues regarding the intensity of forest management. This paper aims to explore the dynamics of forest cover loss in the N2k sites of Dobruja Region, Romania prior to their designation (2001-2007) and afterwards (2008-2014, 2015-2020), based on spatial data and GIS techniques. The forest cover loss registered during the aforementioned three time intervals was computed using the dataset provided by GLAD and Global Forest Watch. The relative forest cover loss, which represents the loss percentage in the total forest cover, was calculated by integrating the Forest Type data provided by Copernicus for 2018. In over a third (36.36%) of the considered sites, the forest cover loss steadily increased, regardless of the designation as a protected area. Also, 27.27% of the sites registered an increase of the parameter after the designation of the area as a N2k network component (2008-2014), followed by a decrease of the forest cover loss in 2015-2020. The same percentage is also applicable for the reversed pattern – initial decrease, followed by an increase of the forest cover loss. However, the relative cover loss was of low value, oscillating between 0.01% and 4.29%. Such findings may be used for formulating inferences on the efficiency of the N2k network, which is particularly important in the study area, as it includes the second largest and the best-preserved delta in Europe, as well as other high-value N2k sites.
Pinus nigra extractives analysis for green growth
Authors: Chavenetidou M A , Kakavas K V , Birbilis D 
Published: December 2022

Abstract
This study aimed to determine all the extractives from Pinus nigra. Different samples were collected from heartwood, sapwood and bark. A Soxlet device and three different solvents (water, ethanol, dichloromethane) were used to collect the extracts. Chemical analyses were conducted with GC-MS (Agilent 5975C). The results revealed significant amounts of the chemical compounds, such as phthalic acid, squalene, linoleic acid, ethyl oleate, propenoic acid, isopropyl myristate and humulen, which have many applications in green chemistry, novel – functional food and pharmaceutical industries and can be used for green growth, circular economy and environmental integration at the aspect of more effective use of natural resources and forest recovery.
Biodiesel production from high free fatty acid byproduct of bioethanol production process
Authors: Kokkinos Nikolaos , Theochari Grigoria , Emmanouilidou Elissavet , Angelova Daniela , Toteva Vesislava , Lazaridou Anastasia , Mitkidou Sophia 
Published: December 2022

Abstract
Biodiesel is a reliable and promising replacement of fossil diesel. It is stable, less toxic and can be produced from sustainable resources, including a variety of raw materials. Currently, the most widely used are vegetable oils (edible and nonedible), due to their availability. The present paper considers the potential of obtaining fatty acid ethyl esters (FAEE) from corn oil, which is a byproduct of bioethanol production process. The ultimate outcome would definitely increase the profitability of the initial bioethanol production process. The biodiesel production process was implemented in two steps, due to the high content of free fatty acids of the obtained corn oil. The first step includes an acid-catalyzed esterification process and the second step comprises an alkali-catalyzed transesterification process to receive FAEE. Two different catalysts (sulfuric acid and p-toluene sulfonic acid) were utilized and compared each other in the esterification process, in order to cope with high acid number of the raw material. A comprehensive qualitative and quantitative analysis of both feedstock and biodiesel was performed using gas chromatography-mass spectrometry method. The obtained biodiesel was characterized by a significantly lower cloud point compared to the feedstock and high acid number.
The infrastructure contribution to the regional development and the environmental protection: Typologies of regional units based on forest operations engineering
Authors: Louka Vereniki , Arabatzis Garyfallos , Kantartzis Apostolos 
Published: December 2022

Abstract
The purpose of this article is to investigate the contribution of mountainous infrastructure and in particular forest operations engineering in its development, environmental protection, adaptation to climate change and policy making, in order to achieve more rational use of natural and financial resources.
The research focuses on forest operations engineering funded by the Rural Development Program of Greece and were executed or will be executed by the Forest Services and Municipalities of the country during the Programming Periods 2007-2013 and 2014-2020 respectively. Data related to reforestation, fire protection, mountain waterworks and forest road projects constructed in the forest area are being analysed, followed by a description of their role in protecting the adjacent areas from fires, floods and in general effects of climate change, or contribute to regional and local development through assisting accessibility, upgrading the landscape aesthetically, creating jobs, etc. Finally, comparisons are made between the regional units and the clusters - clusters of regional units between the two program periods.
The identification of clusters of regional units will contribute to the creation of a clearer understanding of the problems of the mountainous area and to the evaluation of the possibilities for a more rational development, creating the conditions for the choice of alternatives, depending on the general economic or social objectives.
The data are taken from the Rural Development Program and relate to the funding that has been given or projected to be given for the execution of forest technical projects over two programming periods (2007-2013 and 2014-2020) at the level of regional unit. The data are processed by methods of descriptive statistics and multivariate analysis and in particular the cluster analysis of the executed and to be executed forest technical projects (especially projects related to reforestation, fire protection, mountain waterworks and forest road projects). This typology is particularly relevant, in the context of the effort for more rational mobilization and planned utilization of financial resources, based on the comparative advantages of each cluster-cluster of regional units.
Magnetic declination and climate change
Authors: Dimitrios Kampolis 
Published: December 2022

Abstract
Earth’s Magnetic Field is the magnetic field extended from inner Earth till out to space, meeting the solar wind. Its importance is crucial due to the deflection in most of solar wind having as a result the existence of ozone layer and the protection of Earth from UV radiation - a basic mechanism for preservation of life on Earth.
Although the magnetic field is deeply studied for its contribution to life preservation, an important question is still unanswered - the possible relationship between Earth’s magnetic field and climate. Plenty of studies are focused on correlations involving time series and ionospheric variations but the physical mechanism remains unknown.
Here, we propose an explanation based on time series (Historical Magnetic Declination) and the ionospheric variation over Europe as well as in other parts of the world, with a focus on zonal winds. We’ll examine a time series from Middle Ages till modern times in correlation with solar activity and weather history data, to support the hypothesis that there is a link between Earth’s climate changes and geomagnetic field variations. Finally, we’ll try to predict the climate characteristics of major parts of the globe for the following years.
Global warming, thermal engines’ efficiency and GHG emissions: The vicious circle of Climate Change
Authors: Yfantis Elias , Paradeisiotis Andreas , Ioannou Constantina , Nikolaou Ioannis 
Published: December 2022

Abstract
Global warming affects human beings and nature’s ecosystems. Apart from the observed, monitored and measured negative effects on human health and biodiversity, the application of the Laws of Thermodynamics proves that thermal engines can also be affected by having their thermal efficiency reduced due to the decreased value of ΔT (temperature difference between the two heat reservoirs). Considering that the global outcome is kept constant (same power demand and supply), a continuously decreased efficiency results in increased fuel consumption and thus higher CO2 emissions. Since CO2 as GHG favours global warming, a vicious circle is generated. Even though a slight decrease in thermal efficiency seems to be marginal and, thus, ignorable, the vast use of thermal engines in industrial power production and in transportation and the corresponding fossil fuels consumption results in a significant increase in CO2 emissions. The current study examines thermal engines (both for transportation and power generation on board the vessels) and estimates their GHG emissions. The present work, being part of an ongoing vast study on decarbonization, deals with the Carnot and Diesel thermal cycles. Examination of Otto, Dual Combustion, Joule/Brayton, and Rankine cycles will follow. The scenarios are examined to support decisions regarding actions that must be taken to start considering available complementary solutions which provide different levels of technological maturity, cost-effectiveness, and applicability.
Climate Change and SMEs: Green Transition, European Institutional Framework & Necessary Adaptations to Increase the Competitiveness of SMEs in the Region of Western Greece
Authors: Margosi Maria 
Published: December 2022

Abstract
Over the last decade, the climate crisis has been recognized as a great threat to humanity on a global and institutional scale. In this context, every country, with the European Union (EU) paving the way, is planning the ways and means of transitioning to a more sustainable future. Inevitably, the transition will affect citizens’ daily life and countries’ economic activity. In this framework, small and medium enterprises (SMEs) have a central role; especially in countries such as Greece, where most of the enterprises are SMEs. Thus, both the EU and the UN are promoting policies and incentives for SMEs so that they will be actively involved in promoting sustainable development goals. With the Multiannual Financial Framework 2021-2027, the EU decided to use € 401 billion to assist innovations in the fields of green transition and renewables, including SMEs to these actions. At the same time, the National Plan for Recovery and Sustainability “Greece 2.0” is moving in the same direction. Thus, the present study is an attempt to record the actions, reforms, and financial tools that “Greece 2.0” offers to SMEs, focusing on the region of Western Greece. At the same time, we will try to capture the impacts of natural gas introduction in the region. The study aims to outline the future of SMEs in Western Greece based on the current situation and the possibilities that the green transition will bring.
Accuracy of topographical instruments and Unmanned Aerial Systems for mapping and surveying environmental projects.
Authors: Kolkos G. , Stergiadou A. , Kantartzis A. , Tselepis A. 
Published: December 2022

Abstract
For the implementation of environmental technical projects, such as the urban forest management, a key element is the topographical and cartographic mapping of the area. Topographical instruments are based on digital, aerial or satellite information’s that can be used for producing topographical maps. This research aims to highlight that UAVs in combination with low-cost survey methods, produce topographical mapping with accepted accuracy for the implementation of environmental projects, how we can survey a road network in order to produce digital topographic maps and also how the implementation of four different ways of measuring can help us to accomplish it. The methods for executing topographic projects differ in quality, accuracy, time and cost. The results of surveying with a total station, a binary satellite positioning system, a handheld satellite positioning system and an unmanned aerial system were compared based on the accuracy of the results. Estimation of measurement error combined by the time required and the cost of each instrument and associated software for data processing were estimated. The results obtained prove that low-cost methods give sufficient and acceptable accuracy; especially the Unmanned Aerial Systems, are capable of being used for the design and implementation of forest urbanization studies.
Energy valorisation of the residual biomass from greenhouses in the framework of a circular economy
Authors: Gioulounta Kleio , Kosmadakis Ioannis , Elmasides Costas , Diamantis Vasileios , Piskilopoulos Arsenis , Amiridis Iosif , Stamatelatou Katerina 
Published: December 2022

Abstract
Thrace Greenhouses S.A. cultivates 5000 t y−1 cucumbers and 3500 t y−1 tomatoes hydroponically on 170,000 m2 of land. During cultivation (from February to November), suckers and leaves are removed regularly, producing 7,000 – 8,000 t y−1 residual green biomass. The anaerobic digestion technology was applied at laboratory scale, to explore the potential of valorising the generated residues for biogas production. The latter ranged between 18 and 30 NL methane per kg of fresh biomass (suckers or leaves, respectively). Considering a typical mixture of suckers and leaves produced during the cultivating season, the methane produced annually was estimated at 140,000 m3. The biogas can be used as a fuel in a combined heat and power (CHP) system (cogeneration). CHP was considered the central unit in a hybrid energy system (HES) integrated with batteries, aiming to provide energy autonomy to the greenhouses. Moreover, the flue gas from the CHP containing 10% CO2 and 9% O2 could be used as a source of CO2 in the greenhouses. In this case, trace gases (NOx: 401±37 ppm, NO:168±15 ppm, NO2: 150±18ppm, CO: 401±60, SO2: 1.4±2.2) present in the flue gas should be removed and/or diluted with air before entering the greenhouses.
Use of new indices for the quantification of climate change based on air temperature variability
Authors: Zacharaki K , Tseliou A , Rapsomanikis N , Zervas E 
Published: December 2022

AbstractThe current study attempted to investigate the temperature’s variability through the selection of indicators that refer mostly to the increases and decreases of three typical values of daily temperature (mean, maximum, minimum). The primary meteorological data that has been used come from the station of the Hellenic National Meteorological Service in Tatoi, the time period 1955-2001. The time series of the maximum and the mean number of days with a continuous increase or decrease in the daily temperature was investigated seasonally and annually. In addition, the number of switches (increases/decreases) on annual and seasonal scales was analyzed. The results of the time series analysis led to the indication that as time passes temperature’s variability grows with more switches (ups and downs), while its variations become a bit milder.
Sustainable Stormwater Management at Urban Expansion Areas of Potential Significant Flood Risk
Authors: Markou D 
Published: December 2022

Abstract
The Preliminary Flood Risk Assessment (PFRA) for the Greek territory, according to European Directive 2007/60/EC, was completed in 2012 and was revised in 2019. Areas of Potential Significant Flood Risk (APSFR) were defined (and revised) for each River Basin District (RBD). Meanwhile, in 2018, the Flood Risk Management Plans (FRMPs) were approved - by Greek Authorities - for each RBD. In the FRMPs specific measures are proposed for the funding of Stormwater Management (SM) projects that will be designed according to the principles of Sustainable Development (SD), i.e., Best Management Practices (BMPs), Green Infrastructure (GI), Low Impact Development (LID), Urban Natural Water Retention Measures (NWRM) and Sustainable Drainage Systems (SuDS). Within this framework, a preliminary study is drawn up in order to specify some innovative proposals for Sustainable Stormwater Management (SSM) in three areas located into the APSFR of RBD ‘EL11’ (Eastern Macedonia), located in Northern Greece. Two of these areas, Perigiali and Nea Peramos are coastal, while the third one, Doxato, is a continental, plain area. Urban expansion plans are approved for all three cases. The study proposes the implementation of an Innovative Stormwater Management Plan (ISMP) for each area.
The image of the urban space. Social semiotics readings, data, and assumptions
Authors: Pamporis V , Micheli A 
Published: December 2022

Abstract
Contemporary urban space and contemporary urban life is rife with signs and markers with either collective or individual meaning, as the main symbolic regulator/leader in the socio-cultural presence and management of urban space. Urban city centres present a high degree of sign density that on the one hand express established conventional signs (in the strict sense of the term), which are accepted in a fairly, general way, and on the other hand define semantic symbolisms according to which the regulating modes and attitudes in our urban behavior are respectively indicated. This paper focuses on the ambiguity aspect of conceptual collective urban signs by examining important research variables such as: the degree of distinctiveness of the signs, the representation of the idea they ‘convey’, especially both as technical standards and as socio-environmental images of form.