bluuebunny/crossref_metadata_2025 huggingface dataset:
"READING IN A FOREIGN LANGUAGE AND THE DEVELOPMENT OF COMMUNICATIVE COMPETENCES AT THE LEVEL OF SECONDARY SCHOOL PUPILS "
Authors:   Centre for Multicultural and Interlinguistic Studies, Spiru Haret University, Chirimbu Sebastian , Barbu-Chirimbu Adina ,   Centre for Multicultural and Interlinguistic Studies, Spiru Haret University
Published: May 2023

We all agree that reading has a decisive role in enriching and developing students' knowledge for the activation of vocabulary, for the growing taste for reading, for beauty, developing imagination, the power of comparison. Through reading the children get to know more characters, go through many stories, identify themselves with the characters and learn to support their point of view. The issue of educating the taste for reading is extremely delicate, the demarcation between tools offered by the school and the pleasure of reading, which is much more difficult to obtain through standard methods in the classroom. Teachers in general and teachers of a foreign language in particular can only contribute to the formation of this passion, they can help children become autonomous readers. Didactic games remain active methods that contribute to the full development of the child's personality.
"SPORTS VOCABULARY IN ENGLISH AND SERBIAN IN THE LIGHT OF TRANSLATION CHALLENGES "
Authors:   Sinergija University, Budinčić Valentina , Dabić Tijana ,   Sinergija University
Published: May 2023

Due to the powerful influence of English on Serbian in the sports field, which has been present since the nineteenth century and which is nowadays particularly striking, numerous translation concerns in this field are emerging. In order to point out some possible translation difficulties which can appear as a consequence of the lack of sufficient terminology knowledge in this field in English and Serbian and due to the complex socio-linguistic and cross-cultural influences, the authors focus on several lexical issues which can cause these difficulties: false friends, collocations and lexical gaps. The sports terms analyzed in this paper are extracted from the detailed contrastive analysis of English and Serbian sports terminology, which included terms from over 100 sports which are popular all around the world. The results of the research can be useful for linguists who are interested in contrastive analysis and translation studies, as well as for ESP teachers.
Reflections on the Socioecomic Role of Waqf in an Islamic Economic System
Authors: Shehu U.R. Aliyu
Published: May 2023

Promotion of socioeconomic security peaks as a major public policy drive especially in developing and emerging economies. Waqf as a socioeconomic tool emphatically forms part of the ethical values of Islam and is seen as a primary vehicle for financing Islam and the society. This paper aims to provide reflections over the socioeconomic roles of waqf institution in tackling social security challenges for upliftment of the Muslim Ummah. The paper employs a non-experimental qualitative research methodology based on deductive method of analysis of jurisprudential and literature based-evidences. A socioeconomic framework was intuitively developed by the paper for logical analysis. The paper establishes that socioeconomically, waqf institutions across the Islamic world played immeasurable roles in the areas of provision of social and economic infrastructures, lessening the burden of tax and budget deficits, closing the short fall in tax revenues, tackling poverty and income inequality, boosting economic growth, promoting independent provision of public goods and development of active civil society bonded by spirit of compassion and communalism as against that of apathy and individualism. The paper strongly urges the Muslim Ummah to reestablish and reassert the roles of waqf institutions to free itself from socioeconomic misadventures.
Terrorism as a Threat for Economic Development in Nigeria
Authors: Adamu Abubakar Muhammad
Published: May 2023

Islam condemn terrorism and rejects all its kinds, it legalized trade and investment as a way of earning halal. The activities of Boko Haram sect become a major challenge to the Nigerian government in recent times; it had led to loss of lives and properties in the country especially in Northern Nigeria.  Some of these activities include bombings, suicide, random shooting, burning of police stations, government offices and places of worship, kidnapping of school girls and innocent people, raping, armed robbery, political crises, murder, destruction of communication facilities alongside the attacks carried out by Herdsmen on some communities in the northern part of the country. Many lives and properties have been lost and a large number of citizens rendered homeless, many women are now widows, children become orphans with no hope of the future. Government had made uptight efforts to tackle these challenges posed by terrorism in the region and put an end to it but the rate of insurgency and insecurity is still disquieting. This work is therefore investigated the challenges of terrorism as a major threat on economic development in Nigeria. The scope of this study is limited on impact of terrorism on economic development in Northern Nigeria between 2000-2017. Data used was sourced from interview with related people, newspapers and related journal articles by using historical and analytical methods, the results showed that terrorism impacts negatively on economic development in Northern Nigeria, it has made government to divert resources meant for economic development purposes to security votes, expenditure made by government on security matters had positively impacted on region’s economic development. It is therefore recommended that government must be pre-emptive in dealing with security threats in view of managing security challenges. The government should accelerate the rapidity of economic growth by creating an economy with a relevant economic and physical infrastructure to support business and industrial growth, the government should remain committed and declare war on terrorism and seek assistance/advice from international communities who have in the past faced this kind of challenge and were able to tackle it, grazing grounds and ranches should be built in the region for herdsmen who rear cattle, relevant security agencies should be well train and liaised with international security experts for gaining modern tactics on fighting terrorism, religious leaders, governments, business associations and NGOs should increase their efforts on enlightment, awareness, education and sensitization campaign on the effects of terrorism on social and economic development in the region.
تَعْظِيمُ البَلَدِ الحَرامِ في أدبيَّاتِ المُفاخَرَةِ بين الحَرَمَيْنِ الشَّرِيفَيْنِ
Authors: الأستاذ الدكتور مصطفى محمد رزق السواحلي
Published: May 2023

يتناولُ هذا البحثُ تجلياتِ تعظيم البلد الحرام في أدبيَّات المفاخرة بين الحرمَيْن الشريفَيْن، ومن المعلوم أنَّ فنَّ المفاخرة يقتضي عادةً ذِكْرَ مثالب الخَصْم، ومع ذلك فقد اتَّفَق الطرفانِ المتخاصمانِ أدبيًّا على حُرْمةِ البلد الحرام، ووجوبِ تعظيمه. وقد أثمر هذا الفنُّ أربعةَ نصوصٍ في المفاخرة بين الحرمَيْن، هي: المرورُ بين العـَلَمَيْن في مفاخرة الحرمَيْن؛ لأبي الحسن الزَّرَنْدِيِّ، ومفاخرة بين مكَّة المكرَّمة والمدينة المنورة، لمحمد بن سليمان، والحُجَجُ الـمُبِينة في التفضيل بين مكَّة والمدينة، لجلال الدين السُّيوطيِّ، ومقامة ساجـعة الحرم في المفاخـرة بين المدينة والحرم، للسُّيوطيِّ أيضًا. وقد رصد البحثُ مظاهرَ التعظيم التي أوردها المؤلِّفون الأربعة، وصنَّفَها حسب أبعادها: الدينيّة المبنيّة على الآيات والأحاديث والآثار الواردة في فضائل مكَّة المكرَّمة. والتاريخيّة القائمة على مسائلَ تاريخيَّة؛ كأوليَّتها وتحريمها وتعظيمها منذ الجاهليَّة. والإنسانيّة المتعلِّقة بمن عاشوا فيها من الأنبياء والخلفاء والعلماء. والجغرافيّة المبنيّة على وجود كثير من المشاعر المقدَّسة فيها. والرمزيّة المؤسَّسة على دَلالاتِ الألفاظ التي وظَّفها الأدباء توظيفًا مُوحيًا. والنفسيَّة الصادرة عن الإحساس بالسَّكِينةِ والطُّمَأنينة في رحابها. والأسْطوريّة التي تورَّط فيه بعض المؤلِّفِين، فأوردوا حكاياتٍ مُخْتَلَقَةٍ، وبعضَ الأحاديث الضعيفة أو الموضوعةِ. وقد انتهى البحث إلى جملةٍ من النتائج أهمُّها: الحضورُ الحيُّ للحرمَيْن في الأدب العربيِّ وبخاصَّة في أدب الرحلات وأدب المفاخرات. وتميُّزُ نصوص أدب المفاخرات عن كتب الفضائل بما فيها من حِوارٍ حيٍّ يُغْرِي بالمتابعة. وامتناعُ طرف المعارضة عن ذكر ما يشينُ الحرمَيْن الشريفَيْن. والحريَّةُ الفكريَّة التي تمتَّع بها المفكِّرون في تناول هذه المسائل. ولجوء بعض المتفاخرين إلى أحاديثَ ضعيفةٍ وآثارٍ لا وَزْنَ لها؛ لنصرة مذهبهم. وإقحام بعضِ المؤلِّفين أنفسَهم في قضايا خلافيَّةٍ شائكةٍ، مثل المفاضلة بين الرَّوْضَةِ النبويَّةِ والكَعْبةِ الـمُشَرَّفةِ..
Frequency Stability Enhancement Using ANFIS Based Inverter Power Control in Low Inertia Power System
Authors:   Electrical engineering, The Kavery Engineering College, Mecheri, Salem, Tamil Nadu, India., N Selvakumar , V Gokulraj , M Guruprasanth , K Santhoshkumar , G Sundharrajan
Published: May 2023

Electricity generation is the process of generating electrical power from sources of primary energy. There are various methods of electricity generation on different types of energies. Among the source such as thermal power, nuclear power, or the renewable energies the cost of Generator electricity is relatively low. world wide ,about 20% of all electricity is generated by Generator power. Modern Generator turbines can convert as much as 90% of the available energy into electricity. In Tamil Nadu, there are 29 Generator power schemes having individual station capacity over 25MW aggregating to an installed capacity of 2,212.2 MW . At present there are 16 small /mini / micro Generator electric schemes with an installed capacity of 71.35 MW in operation in Tamil Nadu. In 2021, global installed Generator power electrical capacity reached almost 1400GW, the highest among all the renewable energy technologies. Generator electric power plant is usually built on a mountainous area and is isolated from the main power distribution system. It requires very efficient control strategy to control the speed of the Turbine in sudden variation and disturbance in the system. The main objective of this project is to develop mathematical model and design a ANFIS Logic Control (FLC) for Generator power plant during different fault schemes. In this project the ANFIS Logic Control (FLC) is used to control the frequency of the non- linear Generator power plant. The different types of fault models such as single phase ground fault and phase to phase fault are applied to the ANFIS Logic Control (FLC) Key Word: Solar panel, Wind Mill, Inverter, Frequency stability
Automated Driver Drowsiness Detection
Authors:   B. Tech, Department of CSE, SRM Institute of Science & Technology, Delhi-NCR, India., Dhiman Shivam
Published: May 2023

This project uses image processing and Python programming language to create an automatic sleepiness detection system for drivers. The system's objective is to develop an algorithm that can reliably gauge a driver's sleepiness under various circumstances by using real-time grayscale photographs. The driver will be observed by the system as it scans their face and eyelids for hypo vigilance, which is a precursor to tiredness. To properly determine the driver's level of sleepiness, the system entails three steps: feature selection, eye-pair state detection, and decision-making. The algorithm will differentiate between the two states on a collection of captured photos of both tired and awake drivers. To identify sleepiness in drivers, facial feature recognition algorithms has been employed, with an emphasis on the eye pair. Images will be taken with a mounted camera. For the system to successfully be integrated into current driver assistance systems, it will be measured on how well it is able to identify tiredness. The project's importance stem from its ability is to increase road safety by identifying driver sleepiness, a major contributing factor to accidents on the road. In conclusion, this research will significantly impact road safety by tackling the problem of accidents caused by drowsiness.
Enfoque diagnóstico del paciente con sospecha de infección por VIH
Authors:   Universidad de Antioquia, Zuluaga Gómez Valentina , Galeano Toro José Alejandro ,   Universidad de Antioquia
Published: May 2023

Comprender el comportamiento temporal de los marcadores serológicos/virológicos y el rendimiento diagnóstico de las pruebas disponibles para el diagnóstico de infección por VIH.
An Improved Emergency Blow Theoretical Model for Naval Submarine Blowing System and Experimental Verification
Authors: Yi Qi , Zhang Kang , Lin Boqun , Zhang Wanliang
Published: May 2023

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An improved emergency blow model is proposed, which is based on the traditional emergency blow model and takes into account the influence of compressed air overflows from flood holes in the later stage of blowing. In order to verify the prediction accuracy of the improved emergency blow model for tank blowing, the full-scale model experiment of tank blowing was conducted to investigate the effects of air source volume, air source initial pressure, and flood holes diameters on blowing. The process of air release from bottle and main ballast tank drainage can be accurately simulated by the improved emergency blow model, and the prediction error of tank air peak pressure is shown to be <10%. Additionally, it is found that the air source volume has no effect on the tank’s air peak pressure or tank drainage rate. By analyzing the dynamic characteristics of tank air pressure, it is found that the dynamic change trend of air pressure differs between flood holes with small and large diameters. In the small diameter conditions, the air pressure reaches the maximum when the compressed air just enters the tank; however, under large diameter conditions, the peak pressure comes before the accumulated air pressure is released. The experiment and simulation demonstrate that increasing the area of the flood holes has a decreasing effect on the amount of air accumulated in the tank, and that the decreasing effect becomes more pronounced as the air source initial pressure increases.

Introduction

To carry out military operations, submarines are deployed both underwater and close to the open surface. About 170 submarines have sunk since they were originally created as a result of an accident, such as a fire, explosion, malfunction, grounding, or collision (Park & Kim 2017). Submarines run the risk of losing safety control in these critical situations. The best method of self-rescue is emergency floating to the surface to prevent bottoming or going deeper than allowed (Liu et al. 2009). A key factor in emergency rising to the water’s surface is the compressed air blowing mechanism. In such an operation, supplying air to the main ballast tank and blowing out ballast water should be used to achieve positive buoyancy or recover a positive pitching moment, which can be used to restore the safe depth of the submarine. Emergency blow is the term used to describe the process of directly supplying air to the main ballast tank without using a high-pressure valve column. The emergency blow is explored in this work because its influence is significantly greater than that of usual blowing, or traditional blowing.
El desafío que representan las obras creadas por inteligencia artificial al derecho de autor en Colombia
Authors: Benítez Vargas Marlon Antonio , Rico Duarte Laura , Niño Hernández Fanny Patricia
Published: May 2023

La Cuarta Revolución Industrial ha dejado a su paso grandes retos en el ámbito del derecho. El presente documento analiza la protección jurídica que se le puede brindar a las obras creadas con inteligencia artificial, frente al ordenamiento colombiano en materia de derecho de autor; teniendo en cuenta que este es uno de los principales debates que actualmente se encuentra vigente en el mundo. En tal sentido, con miras a resolver de qué manera se pueden amparar dichos productos, se hace necesario identificar el nivel de incidencia de esta tecnología emergente en los procesos creativos y su eventual garantía, bajo las figuras jurídicas que ofrece el sistema de propiedad intelectual.
Optimizing Beekeeping Production through System Dynamics Modeling: A Case Study on Forecasting Bee Queen Rearing Capacity
Authors: Smilga-Spalviņa Agnese , Spalvins Kriss , Veidenbergs Ivars
Published: May 2023

Commercial bee queen rearing is an intensive process in which the main commercial product, bee queens, are produced in a short period of time. The intensity is even more severe in regions where the beekeeping season is shorter, as preparation, rearing initiation and capacity increase during the season consume a lot of time. Bee queens can be divided into different product categories: virgin, mated, mated in isolated station, and instrumentally inseminated queens, and they can be further divided by race, pedigree, and colony characteristics. Each category is with varying time and resource consumption. To optimize bee queen rearing and choose the appropriate rearing strategy, product categories, production capacity dynamics, and other aspects, the authors of this case study developed a system dynamics model with the aim of finding the optimal number of production units, the most appropriate product groups and their volumes, according to changes in income and time consumption. The model clearly shows the system’s sensitivity to having too many production units – nuclei and queen rearing colonies. Too many production units led to ineffective use of nuclei, increased bee queen mortality, high bee queen surplus, high human and time resource costs and unnecessary batching of orders. The developed model demonstrated how to predict the optimal production capacity and how inefficiency leads to the inevitable collapse of the bee queen rearing system, from which the bee queen breeder cannot recover during the season. The model allowed to conclude that balancing material and human resources in bee queen rearing is very important for efficient production.
Analysis of the Influence of Power System Diversion on the Optimal Supply Strategy of Renewable Power Plants
Authors: Endemaño Ventura Lazaro , Serrano González Javier , Riquelme Santos Jesús Manuel , Roldan-Fernandez Juan Manuel
Published: May 2023

This paper presents an analysis of the influence of power system deviation prediction on the bidding strategy of renewable generation units in spot markets. The optimal bid that a renewable generator makes is subject to the best possible forecast at the time it submits the energy bid to the spot market, which is usually between 12–36 hours in advance of the time of delivery. With these lead times, renewable generators have to assume a significant volume risk in relation to the difference that may occur between the energy finally delivered and the energy previously committed for their participation in the market, since deviations from the committed energy will be valued at the deviations price. In this sense, the analysis carried out in this work shows that the prices of deviations are highly influenced by the energy needs to be raised or lowered by the system at the time of delivery. In other words, in the event that the deviation of the renewable generator goes against the system, the generator will generally have a higher penalty, having to assume the cost of the energy deviation at a price higher than the spot market price. On the other hand, if the plant’s deviation benefits the system, the penalty will be significantly lower (and sometimes even zero). The proposed analysis methodology develops the formulation of the expected benefit of the plant obtained through its participation in the spot market and subsequent settlement of the deviations. This formulation includes the modeling of the effect of the system deviation on the plant’s profits, which allows to satisfactorily identify the influence of the prediction of this variable on the optimal offer strategy. This methodology has been tested for the case of a wind farm operating in the Spanish market. For this purpose, real data of forecasts and final production of the wind farm have been used, as well as real data of the spot market, prices of the balancing service and real deviation of the system, which has allowed to verify in totally realistic conditions the importance of the prediction of the direction of deviation of the system in the optimal bidding. In this way, it will be possible to establish new optimal bidding strategies that focus efforts on advanced prediction techniques for this variable, which will result in greater benefits for wind power plants for their participation in the energy markets.
Carbon Sequestration Potential of Biomass-Based Products: A System Dynamics Modeling Approach for Grassland Management
Authors: Kasakovska Aleksandra , Vamža Ilze
Published: May 2023

It is known that forests are significant carbon storage, as well as harvested wood products. Both sectors are included in the national greenhouse gas inventories. When wood or other types of biomass grow, it absorbs carbon dioxide through photosynthesis. If biomass is used in the production of new products, the carbon stored in them is effectively removed from the atmosphere and held in the product. Carbon stored in products is considered temporary because the products eventually will burn or decompose and release carbon dioxide back into the atmosphere. However, when products are used for long-lasting applications, the carbon stored in them can remain sequestered for many decades, which can significantly contribute to climate change mitigation. If it is possible to store carbon in wood products, the question arises as to whether it is also possible to promote carbon sequestration in products with other types of biomass. In this work perennial biomass was analyzed. It is a product of semi-natural grasslands, where grass cutting is necessary, which produces grass biomass that is often not fully used. A literature analysis was performed to select suitable products with different carbon storage periods and minimal production emissions, such as those made from biorefining, boards for packaging or building materials, and biochar for soil carbon sequestration. A system dynamics model was developed to estimate carbon stocks and flows between atmosphere, living biomass and products. The base scenario is modeled according to carbon flows in grasslands according to IPCC guidelines – grasslands are net carbon sources and the carbon concentration in the atmosphere only increases. The addition of a product-manufacturing scenario decreases the carbon concentration in the atmosphere.
Impact of Electric Vehicle Charging Infrastructure on the Electric Load Profile of Power System: The Case of Latvia
Authors: Valdmanis Gunārs , Vītols Rūdolfs , Bažbauers Gatis
Published: May 2023

The number of electric vehicles (EVs) is increasing rapidly, and charging infrastructure must keep up with that pace. With increasing charging load, a power system must adapt to the increasing power demand. The research question of this study is: what impact of EV charging on electric load profile is depending on the number of EVs and the mix of charging units (slow, medium, fast)? How much of the total power demand of EVs can be supplied from renewables, i.e., wind and solar power, considering the installed capacities of these technologies, and the match between power production and consumption. Energy system modeling on an hourly basis for different scenarios of the mix of charging units, number of EVs, and installed capacities of wind power plants and solar PVs was used as the method. EnergyPLAN software was used as the modeling tool. The results show the total power demand, peak load, and share of EV charging power demand that can be covered by renewable power technologies for Latvia’s power system in the year 2050. The results are obtained for scenarios of different combinations of EV charging units.
LCA Sensitivity Analysis of an Energy-Biochar Chain from an Italian Gasification Plant: Environmental Trade-offs Assessment
Authors: Marzeddu Simone , Cappelli Andrea , Paoli Riccardo , Ambrosio Andrea , Decima María Alejandra , Boni Rosaria , Romagnoli Francesco
Published: May 2023

Due to its potential applications in bioenergy production, coproducts (bio-oil and syngas), mitigation of global warming, sustainable agriculture, pollutant removal, and other uses, biochar has drawn interest from all over the world. Producing and using soil-based biochar as a method of carbon sequestration could help reduce emissions while benefiting the soil and opening up possibilities for bioenergy production. However, to characterize the production cycle’s environmental and energy loads and confirm all of the advantages of biochar, Life Cycle Assessment (LCA) represents a reliable tool for evaluation. This work is based on continuing the study of Marzeddu and Cappelli (Marzeddu, Cappelli, et al., 2021) to understand the environmental impact of an energy-biochar chain involving a gasification plant in Italy. In the LCA carried out in the previous paper for the characterization of biochar, which is used as a soil conditioner, soil carbon sequestration, nitrous oxide emissions, fertilizer use, and water use for irrigation were considered. The results showed that the use of gasification for energy and biochar is an attractive strategy for mitigating the environmental impact analysis, especially climate change, with a net decrease of about ‒8.3·103 kg CO2, eq. The previous study was lacking a sensitivity analysis. For this reason, a sensitivity analysis is proposed in this study to consistently assess the environmental trade-offs of the biochar and the amended soil. In specific for the upstream processes the sensitivity is addressed to the selection of a different type of woodchips, for the core process in terms of selection of different packing material, and to the entire cradle-to-grave perspective by improving the logistics of the transportation, the distances within the supply chain and the choice of BAT technology for the transportation vehicles. This study highlights strategic research developments that combine to find potential environmental trade-offs and thresholds towards using biochar and its final use as a soil conditioner.
Life Cycle Assessment of an Industrial Laundry: a Case Study in the Italian Context
Authors: Mezzanotte Valeria , Venturelli Sara , Paoli Riccardo , Collina Elena , Romagnoli Francesco
Published: May 2023

The high volumes of wastewater from industrial laundry with known toxicological concerns represent a relevant source of pollution for water bodies. Moreover, the unavailability of a detailed and specific Life Cycle Inventory (LCI) referring to the use of detergent within the laundry system could undermine the overall quality of the environmental assessment. This is related to the use of a substitutional product or proxy dataset for specific processes like the use of detergents. Laundry services are also known as highly energy consuming sites. This paper thus aims to make a Life Cycle Inventory (LCI) and Assessment (LCA) for an industrial laundry to provide the environmental profile for an Italian case study. The primary data input to finalize the LCI came from data collected directly from an Italian industrial laundry, integrated with literature, data provided from supporting databases (i.e. Ecoinvent 3.8), and data specifically obtained from the technical datasheets of detergents. The industrial laundry system considers the product’s overall supply chain: extraction and manufacturing of raw materials, including the detergent, transportation and logistics, the industrial process associated with the laundry activity, wastewater treatment, recirculation packaging, and final disposal stages. The calculated environmental profiles refer to the functional unit of 1 kg of linen washed by a standard washing cycle. The system boundaries of this study include the production stages of the process. The analysed activities are the transportation for the delivery and collection of linen, the purchase of raw materials, and the sanitization and washing processes. SimaPro 9.2 software and the ReCiPe 2016 H method are used for the LCA study. The baseline scenario has been compared with an alternative scenario introducing renewable energy technology (i.e. solar PV panel). The result shows a total impact of 12.77 mPt. The most impacting activities are the washing phase (4.62 mPt), the ironing phase (4.29 mPt), and the drying phase (1.56 mPt). The greatest impact in the washing phase is caused by the use of detergents and washing products. It is observed that most of the impacts fall into the categories of ‘Global Warming, Human Health’, ‘Fine Particulate Formation’, ‘Carcinogenic Human Toxicity’, ‘Non- Carcinogenic Human Toxicity’, ‘Fossil Resource Scarcity’. The midpoint category with the highest impact is ‘Fine Particulate Formation’ with a value of 5.18 mPt. The alternative scenario introducing renewable energy technology (i.e. solar PV panel) reduces the impact by 19.7 %. Sensitivity analyses have been performed to evaluate the LCA model’s uncertainty, with specific reference to the washing agents, the transportation of raw materials, and the energy consumption.
Off-shore and On-shore Macroalgae Cultivation and Wild Harvesting: an LCA-based Evaluation from Baltic Case Studies
Authors: Paoli Riccardo , Bjarnason Bjarni , Ilmjärv Tanel , Romagnoli Francesco
Published: May 2023

Seaweeds are organisms with unique characteristics. They contain a broad spectrum of micro and macro elements (i.e., minerals, carbohydrates, proteins, lipids, pigments, and vitamins). Furthermore, they have a very high growth rate and are present in large quantities and species in nature. Therefore, they represent an ideal feedstock for a biorefinery concept. Historically, macroalgae used in biorefineries have been harvested directly from the sea or the shores (off-shore technique). However, recent studies are analysing the possibility of creating on-shore cultivation facilities. This research aims to perform a Life Cycle Assessment (LCA) study that analyses and compares the environmental impact of two seaweed cultivation and wild harvesting techniques in the Baltic conditions based on existing pre-commercial and commercial projects. Inventory data are collected directly from two macroalgae producers in the Baltic Sea region (one wild harvester and one on-shore), integrated with literature, and then normalized to the selected functional unit, i.e., 1 ton of harvested fresh macroalgae. The results, implemented with SimaPro 9.4 software, determine which of the two techniques has the highest environmental impact and which are the most sensitive environmental indicators. Furthermore, the results underline the critical parameters for the two cultivations (i.e., fuel consumption and electricity), contributing to identifying environmental benchmarks for further optimization strategies. The alternative scenarios analysis included in the study aims to explore and highlight the effect of the variation of selected input parameters or assumptions to provide a consistent assessment of the uncertainty of the model outputs and the main findings in terms of environmental impacts.
The Impact of a Permeation Grouting Technique Quantitatively Assessed through a Process-Focused Life Cycle Assessment
Authors: Castellanza Riccardo , Collina Elena Maria , Pierani Matteo , Romagnoli Francesco , Paoli Riccardo
Published: May 2023

Permeation grouting technique can be considered nowadays a well-established ground improvement strategy in urban built environments, where an accurate fine-tuning of its component can lead to tailored and efficient interventions. But how environmentally impacting is it? Using life cycle assessment analyses (LCA) and focusing on the construction phase, this research highlights the leverages that can improve the environmental performance of this geotechnical construction process. The alternative approaches in terms of materials and processes are identified, quantified and compared using the standard output of the LCA analysis and represent the ideal input for the three-step sustainability assessment method for geotechnical infrastructure developed by the authors
To Burn or not to Burn. Literature Review
Authors: Terjanika Viktorija , Keleja Daika , Pubule Jeļena
Published: May 2023

The amount of potentially recyclable municipal solid waste in the world is growing every year. At the same time, the demand for energy is increasing globally. Waste-to-energy (WTE) technology has been proposed as a potential solution to this problem, whereby waste is burned to produce electricity. Although promoted as an environmentally sustainable solution, doubts persist regarding its actual eco-friendliness. This article analyses the literature and discusses the advantages and disadvantages of WTE technology in Latvia and at the general level. The focus of this article is the potential advantages of WTE technology, which encompass a decrease in landfill waste, retrieval of valuable resources, production of energy, and improving financial feasibility. Disadvantages, such as a potential increase of emissions, loss of valuable materials, breaking development of recovery technologies and practices, and neglection of circular economy plans, are also discussed.
Optimizing Honey Bee Drone Rearing: An Examination of Colony Management Techniques and Their Impact on Sperm Quality
Authors: Smilga-Spalviņa Agnese , Spalvins Kriss , Veidenbergs Ivars
Published: May 2023

The vitality, ejaculation success, sperm quantity, sperm viability and motility directly depends on the breeding conditions of the honey bee drones because since the egg stage, both the larva and the adult drones are fully taken care of by the worker bees. Worker bees choose to care for and feed drone brood only during the season when mating of virgin queen bees takes place in nature. If there is a lack of food resources in the bee colony, the worker bees can decide not to feed both the drone larvae and adult drones and throw them out of the nest. In this field study, the various methods of preparation of drone rearing colonies are reviewed and tested: in the presence of a queen and without one, with an additional feed base (sugar syrup, honey, pollen), various sizes of colonies, etc. Drones were reared in these colonies, then their sperm were collected and sperm motility, viability, cell concentration and sperm quantity per drone were determined. In addition to that, authors also evaluated the parameters characterizing the quality of sperm in different races of honey bee drones.
Biobutanol Production from Agro-industrial by-products using ABE Fermentation: Analysis of Feedstock Effect on Biobutanol Yield and Titer
Authors: Spalvins Kriss , Kusnere Zane , Raita Svetlana , Berzina Indra
Published: May 2023

This study examined a range of agro-industrial by-products that could be used as potential carbon and nitrogen sources for ABE fermentation. In general, the study examined more than a dozen different by-products from dairy, biodiesel, sugar, agriculture, beverage, food, etc. production industries. The by-products were tested to determine which of them would result in higher biobutanol yield and concentration in the fermentation medium. All by-products were used in the cultivation of three bacteria of the genus Clostridium to observe differences also between the strains’ ability to utilize the respective substrates. The test results demonstrated that the most suitable by-products for ABE fermentation, which served as carbon sources, are biodiesel and sugar production by-products and hydrolysates of agricultural residues. These by-products are available in large quantities. The tests show that they serve as a good energy source for the production of butanol fuel. By-products of dairy processing and specific beverage production residues (yeast residues) showed the best results as the most suitable nitrogen sources; however, these by-products are either limited in availability at scale or their transportation is uncompetitive due to the high water content. This study shows that ABE fermentation can be provided with a range of different agroindustrial by-products. The wider use of these by-products in the future can reduce the negative impact on the environment, reduce the production costs of ABE fermentation products and allow obtaining an efficient biofuel – biobutanol, which can compete with bioethanol and biodiesel.
Fungal Hydrolysis of Food Waste: Review of used Substrates, Conditions, and Microorganisms
Authors: Bērziņa Indra , Spalvins Kriss
Published: May 2023

Food production generates significant amounts of organic waste that can have negative effects on the environment, such as water, soil and air pollution, due to lack of efficient utilisation solutions and insufficient disposal practices. Fungi have great enzymeproducing abilities that can be used for hydrolysing various types of food waste. Carried out in optimal conditions, fungal hydrolysis of generated food waste can be fast and efficient. Currently, fungal hydrolysis capacity for waste treatment has only been briefly demonstrated in previous studies. This review focuses on and summarizes different practises showing the potential of fungal hydrolysis for the use inefficient resource management. The main accent was put on what organisms and waste have been used in previously conducted studies. In addition, temperature, pH level and glucose recovery yields were reviewed. It was concluded that food waste can be efficiently hydrolysed and used as substrates for downstream production of value-added products. The optimal temperature for fungal hydrolysis is above 45 °C, and optimal pH level can differ depending on the process. The possibility of fungal strain optimization and creation of the enzymeproducing mutant, as well as the use of other GRAS fungi should be investigated. To explore a wider range of waste residues, researchers must collaborate with manufacturers to conduct tests and valorise new residues for fungal hydrolysis.
Predicting the Fertility of Long-term Honey Bee Drone Sperm Storage through Correlation of In vitro and In vivo Data
Authors: Smilga-Spalviņa Agnese , Spalvins Kriss , Veidenbergs Ivars
Published: May 2023

The article describes a study on the long-term storage of honey bee drone sperm and the evaluation of its quality. The current method of evaluating sperm quality, which involves inseminating queens and waiting for progeny. It is time-consuming and limited by the seasonal nature of beekeeping. The study aims to find correlations between queen fertility rates and sperm quality indicators in the queen spermatheca versus sperm quality indicators after storage in a thawed sperm sample. The study also examines the correlation between number of sperm cells, sperm motility, sperm viability, proportion of worker bee broods, sperm quality indicators in the spermatheca of queen bees, and duration of queen laying. The goal of this study is to validate in vitro-in vivo data and to facilitate future research on sperm storage issues.
Review on Sustainable Cryopreservation and Nonfreezing Storage Solutions of European Honeybee Apis Mellifera Drone Semen
Authors: Smilga-Spalviņa Agnese , Spalvins Kriss , Veidenbergs Ivars
Published: May 2023

The European honeybee Apis mellifera is the main pollinator for most crops used for human consumption. However, a number of diseases, parasites, pesticides and other factors that generally result in the widely described colony collapse disorder weakens honeybee colonies. In order to maintain the existing honeybee germ lines and facilitate the creation of new disease-resistant lines, it is necessary to ensure consistent breeding work, which would also allow the long-term preservation of the unique germplasm lines. One of the most promising solutions for the preservation of honeybee germplasm is the storage of honeybee drone semen. In recent decades, there has been a renewed interest in the preservation of honeybee drone semen using both cryopreservation and non-freezing storage methods. This review looks at the latest developments in novel sperm storage technologies and compares them to well-known preservation solutions. Additionally, the most accessible and widely used solutions will be reviewed, taking into account the cost of the necessary equipment, the complexity of the methods, time consumption and resulting sperm quality.
Use of Single-cell Oils in the Production of Bio-based Epoxy: An Overview of the Most Suitable Microorganisms and Oil Properties
Authors: Spalvins Kriss , Feofilovs Maksims , Valters Karlis , Mika Taras
Published: May 2023

Epoxy resins are widely used polymers that are mainly synthesized from fossil feedstocks. In order to reduce the use of fossil-derived epoxies, various solutions are widely studied, such as replacing conventional raw materials with more environmentally friendly, non-toxic solutions, such as vegetable oil. One of the less studied but potentially highly competitive feedstock for the synthesis of bio-based epoxies is single-cell oils (SCO). Single-cell oils have a number of advantages over vegetable oils, such as the fatty acid profiles of SCO are more suitable for the polymerization of epoxides, the production of SCOs is faster and more environmentally friendly. Thanks to the wide range of SCO-producing microorganisms, it is possible to find the exact SCO that is suitable for the specific application of the produced epoxy. Despite the potential advantages, SCO derived from microorganisms such as yeasts, fungi and bacteria, have received very limited coverage in the scientific literature. Therefore, this review summarizes the available information on single-cell oils and evaluates their suitability for use as feedstock in epoxide synthesis. The following aspects are reviewed in this paper: microorganism strains that can be used in the production of SCO; fermentation rates and SCO yields; applicable low-cost raw materials used for the cultivation of microorganisms; the fatty acid profile of the relevant SCO and other factors that are significant for suitability evaluation of the relevant SCO. To the best of authors knowledge this is the first review paper to summarize potential SCOs for their application in synthesis of bio-based epoxides and first paper to give an overview of fungal and bacterial oils for such application.
Biodiesel with Fuel Additive: An Analysis of Engine Performance, Combustion and Emission Characteristics
Authors: Yormesor Simon Kwashie , Samuel Olusegun David , Enweremadu Christopher Chintua
Published: May 2023

Threats to the environment from exhaust emissions and global warming continue to generate more calls by most governments to end the use of fossil fuels and switch to green fuels. This study aims to examine one of the green fuels that is seeing rapid expansion, namely the biofuel known as biodiesel. Biodiesel is non-toxic, biodegradable, made from renewable sources and can reduce diesel engine exhaust emissions. Even though one of the technical benefits of biodiesel is its ability to be oxygenated in diesel engines without much hardware modifications; however, it has been unable to reduce exhaust tail emissions from diesel engines on its own. In this research, the impact of biodiesel mixed with oxygenated additive, diethyl ether, when subjected to performance, combustion, and emission tests in unmodified diesel engine at different speeds has been studied. Waste cooking oil was transesterified using methanol as a reagent and NaOH as catalyst. The biodiesel was blended manually at room temperature with diesel fuel and diethyl ether in different proportions while keeping the volume of diethyl ether constant at 10 %. The fuel blends (B10D90, B20D80, B30D70, B10A10D80, B20A10D70, and B30A10D60) were subjected to performance, combustion, and emission tests in a single-cylinder, four-stroke diesel engine coupled to a water-cooled Eddy current dynamometer and results obtained compared with diesel fuel. The results showed that all performance characteristics (brake power (BP), brake torque (BT), brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC)) improved with B10A10, which was found to closely resemble diesel. The peak cylinder pressures were higher for the blends, while the cylinder temperatures were comparable to those of diesel. The carbon monoxide (CO), carbon dioxide (CO2), hydrocarbon (HC) and oxides of nitrogen (NOx) emissions decreased more for all tested blends than for those of diesel at all engine speeds. Adding diethyl ether additives improved the physicochemical properties of biodiesel, making it a viable method for using biodiesel efficiently in diesel engines without modifying the engine. The study found that using green diesel fuel with a diethyl ether additive is a potential step toward improving air quality by lowering emissions from stationary, and transportation engines while maintaining optimal engine performance. As a result, using biodiesel-diesel fuels with the appropriate proportions of diethyl either additive has the potential to reduce greenhouse gas (GHG) emissions and ensure benign environment.
Business as Usual for the Biomass Energy Sector? State of the Art and Future Avenues
Authors: Barth Henrik , Ulvenblad Pia , Ulvenblad Per-Ola
Published: May 2023

Many companies are increasingly confronting the challenge of changing their business models as they face a future in which energy solutions are needed that are environmentally, socially, and economically sustainable. Too often, the development process is sequential and stepwise rather than parallel, especially as far as dealing with technological, sustainability, and economic issues. This paper identifies trends as well as challenges and complications in the use of biomass from a business model perspective and address future avenues. We conduct a systematic literature review to identify state of art in the field of business model development in the biomass energy sector. We use several databases to identify international, peer-reviewed research articles published between 2002 and 2022.Our review presents data from more than 200 articles including author affiliation by country, article publication date, article title, journal of publication, journal impact factor, country of empirical data, unit of analysis, research methodology, and research area addressed. The research areas identified include: (i) biomass as an energy source with multiple applications from small-scale household use to large-scale industry use, (ii) biomass as a renewable resource developed based on industrial and political initiatives, (iii) the feasibility of conventional bioenergy, (iv) the industrial ecosystem, stakeholders, and the business environment in the biomass industry, and (v) biomass as a potential energy source that can mitigate the harmful effects of climate change. Although much of this research on the use of biomass takes a technological, logistical, or incentives perspective, our literature review reveals that an increasing body of research takes a business model perspective. This is a promising development, since the future use and growth of biomass as a sustainable resource depends on the successful development of biomass business models that are sustainable in every aspect – social, environmental, and financial.Conclusions drawn from the literature review indicate that the business model researched has mainly focused on three of the building blocks: value proposition, value creation and delivery, and value capture. The building block, value intention, merits more extensive study. This is especially relevant when developing sustainable business models that can meet many of the societal/environmental challenges as defined by the United Nations in its Agenda for Sustainable Development.