The Scientific Journal of Riga Technical University
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Enterprise Integration as a Driving Factor for Guiding Digitalization in a Manufacturing Small and Medium Enterprise
No full textIn the face of rapid technological advancements and evolving consumer demands, businesses increasingly turn to digitalization to remain competitive and redefine industry standards. This article delves into the crucial role of enterprise integration within the context of digital transformation, with a specific focus on manufacturing Small and Medium Enterprises (SMEs). Based on fieldwork within the Innovation Factory North project in Denmark, the study presents a three-dimensional framework – architecture, capabilities, and governance – that is instrumental in guiding manufacturing SMEs through the complexities of digitalization. The architecture dimension explores the dichotomy between monolithic and fog (edge) architectures, highlighting their respective merits and challenges. The capabilities dimension introduces the concept of operational capability stacking, demonstrating how specific information systems, when integrated, yield new capabilities. A list of common capabilities in manufacturing enterprises is provided, offering inspiration for manufacturing SMEs to enhance their operational efficiency. The governance dimension injects a strategic dimension into the digitalization process, emphasizing the need for a balanced approach between technology-driven and process-driven optimization methodologies. The research underscores the strategic nature of digitalization in manufacturing SMEs, recognizing the interconnectedness of architecture, capabilities, and governance in achieving sustained success in the digital landscape. The proposed three-dimensional framework is substantiated through real-world applications within Denmark’s Innovation Factory North project, providing tangible insights and scenarios to navigate the intricacies of the digital landscape effectively
Stepless Transmission Optimization for Green Micromobility
No full textSmall, electrified vehicles are becoming possible for urban environmental mobility due to their environmental performance, including zero-emission driving. Vehicles of this type use electric motors as sources of mechanical energy. Today, two types of transmission are most used in electrical micromobility vehicles (skateboards, scooters, tricycles, quadricycles, mopeds, motorcycles, go-karts, etc.): chain transmission and belt transmission. This transmission types provides a constant gear ratio that can only compromise between the maximum speed and the starting torque values, thus reducing the usage efficiency of the engine. This reduces vehicle manufacturers’ choice of less powerful drive and control elements, as well as balancing performance and efficiency at low and high speeds as well as on terrain.A novel design of a continuously variable transmission (CVT) for an electric go-kart is presented in this paper. The CVT consists of an inertial driving pulley mounted on an electric motor shaft, a timing V-belt, a gear wheel on the drive axle and 2 pressure rolls, which are moved by a servo motor for tensioning the V-belt. Gear ratio of a transmission can change seamlessly in the range of 1.5 - 2.2. The CVT has been tested under real conditions. The top speed of the electric go-kart with the given CVT and motor power 24.7 kW is 133km/h; time to accelerate to the top speed is 25 s. Total efficiency of the transmission (motor shaft, CVT, drive axle and wheels) is 65-72 % now, but there exist a lot of possibilities to improve it in the future. The conditions under which the novel CVT has an advantage over belt and chain transmissions with constant gear ratios have been studied. The developed mathematical model, the method for determination its constants, the algorithm for numerical calculations and the optimization criterion makes it possible to determine the optimal gear ratio for a vehicle with various CVT (not only belt) at any point in time in different racing modes. The model has been proved experimentally during acceleration and deceleration tests of the go-kart; it describes precisely the motion of the go-kart within the speed measurement error.The developed solution is applicable in urban micromobility. An optimized and stable transmission system focused on energy efficiency, resource saving, using less powerful drive and zero-emission
Robust Design of 5th Generation District Heating and Cooling (5GDHC) Systems with Seasonal Thermal Energy Storage via GIS Assessment
No full textThis research addresses the need for a method to compare waste heat potential and recovery in 5th Generation District Heating and Cooling (5GDHC) systems. Prosumer buildings, known for enhancing flexibility, are analyzed using Geographic Information Systems (GIS) and image vectorization to evaluate 5GDHC systems. The study predicts the amount of waste heat available with an R2 of 0.96, utilizing Chaikin's algorithm to refine thermal images for automatic recognition of the sources of waste heat. Emphasis is placed on the absence of a method for asset design in 5GDHC, with considerations for annual energy calculations, radial network connections, and energy shares among building types. Recommendations for building connecting in Belgium are proposed, favoring 'B'/'C'-labeled buildings. The research explores the impact of building design on heating and suggests energy savings through regulation strategy changes. Dynamic models for heat pumps aim to reduce errors and emissions. The study connects energy indicators and GIS software, contributing to a top-down design approach in 5GDHC systems. The overall goal is to contribute to decarbonization and reduce CO2 emissions in the energy sector
Unveiling Future Offshore Wind Potential: A Multi-Criteria Framework for Sustainable Development
No full textClimate change poses a critical threat to the environment and human societies, prompting a shift towards clean energy sources. Among these sources, offshore wind energy emerged as a promising alternative, due to its consistent and strong wind resource availability, coupled with matured technology. However, offshore wind energy being susceptible to the climate change, the efficiency, reliability, and financial viability of the offshore wind farms is location specific. Therefore, the present study introduces a novel framework for identifying suitable regions for offshore wind farm development by considering future projections under the various Shared Socioeconomic Pathway (SSP) scenarios. A weighted multi-model ensemble (MMEwt) created using nine Coupled Model Intercomparison Project Phase 6 (CMIP6) climate models was considered for the analysis. The suitability of a location is evaluated considering richness, stability of the resource, risk, and economic factors. CRiteria Importance Through Intercriteria Correlation (CRITIC) multi-criteria technique is used to evaluate the prominence of each factor Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) technique is used to determine the suitability of each grid within the study area and their hierarchy. Findings of this study showed that the north-western and southern regions within the study area are relatively plausible compared to other regions. The proposed methodology built on the theoretical framework of multi-criteria techniques can be extended to other regions and determine the suitability map of plausible wind regions over the specified area for future time periods
Justification of the Use of Container Technology in Dumping
No full textThe increase in the depth of the quarry is associated with an increase in the work of quarry transport in limited areas, requires a constant increase in the number of transport units, which increases the environmental burden on the environment. The rock mass extracted from the quarry is stored in external dumps, which occupy large areas and significantly worsen the ecology of the region. The operation of mining equipment on dumps with existing technologies causes a number of problems, the main of which is the movement of equipment near the prism of a possible rock collapse. It is proposed to use container technology for transporting the laying rocks in the dump, where the main element of the technology is a mobile lifting machine, which eliminates the need to build roads or railways on board and on the surface of the dump. Self-unloading of container equipment allows you to pour the rock mass directly to the place of laying on the dump. Containers with rock are installed in front of the front of the dump, and the lifting machine is placed on a special platform of the dump. The rock mass is delivered from the faces by dump trucks of any load capacity and unloaded into the hopper of a plate feeder, which fills the containers as they are fed by a quarry lifting machine. the rock is laid in horizontal layers within the step of moving the lifting machine. The weighted average height of the rock rise is equal to half the height of the dump tier. With the new technology, the entire amount of work will be performed by one lifting machine. Increasing the height of the dump to 80 meters with a new method of dumping, reduce the area occupied by dumps by 175 thousand m2 per year. The use of container technology in the formation of the dump allows, when unloading rock from containers into the dump, to reduce energy consumption during the formation of the dump, and increase the economically advantageous height of the dump. This reduces the area occupied by dumps and reduces the harmful effects of mining on the environment. The article discusses the technology of dumping during the formation of dumps using bulldozers in the conditions of Northern Kazakhstan. Traditional technology involves the involvement of a complex of equipment consisting of 8 dump trucks and 1 bulldozer. According to the new technology, the same amount of work can be done thanks to 1 lifting machine. Based on the calculations carried out, it was found that the intensity of dust emissions from internal sources decreases by 1,576 tons per year. A decrease in dust emissions is also observed with an increase in the height of the dump due to a decrease in area, while the difference was 75.57 tons per year. The total decrease from container technology is 1,651.57 tons per year
What Have we Learnt so Far About The Extended Producer Responsibility – Results of Bibliographic Review
No full textNowadays, the environmental impact of the manufacturing sector, particularly in terms of waste management, is receiving increased attention. In this context, extended producer responsibility (EPR) has become an essential environmental policy instrument for all European Union (EU) Member States. This policy principle has also garnered interest from other countries around the world, which recognize its importance. The EU has acknowledged the effectiveness of this instrument and seeks to enhance the sustainability and waste management practices within its manufacturing sector. The operational principles of EPR are regulated at the EU level collectively, while also allowing for individual definition by each Member State. It's important to note that these principles encompass measures primarily aimed at promoting waste prevention, reuse, recycling and other forms of recovery.The aim of this paper is to provide an in-depth insight into the operational principles of the EPR in the EU Member States, its application to different product groups and identify the existing challenges related to assessing the effectiveness of the EPR system via bibliographic review of scientific papers published in “Web of Science” indexed journals
Assessing the Applicability of Solar Thermal Technologies for Industrial Tea Drying
No full textMost process heat being used for various industrial applications is supplied from fossil fuels. Coal, gas, and wood fuel are the most used heat resources which usually power steam boilers for production of heat used in a wide range of industrial processes. Since economic growth is largely linked to industrial production, it implies that, a shift towards use of clean energy technologies in industries is crucial to meet the rising demand of process heat while, cutting down carbon emissions to mitigate climate change. Solar thermal systems have over the past years shown potential as a practical alternative to fossil fuels for production of heat for several applications including, water and space heating, industrial process heating and electricity generation in thermal power plants. This study seeks to assess the feasibility of employing solar thermal technologies for drying purposes at Tingamira-Tanganda Tea estate in Zimbabwe. Systems advisor model (SAM) was applied to simulate performance of linear Fresnel (LF) and parabolic trough (PT) solar thermal technologies for industrial tea drying. Information on daily heat demand, required process temperatures and current heat sources was obtained to inform the design process of the proposed solar thermal systems. LF system exhibited better techno-economic performance. It requires a smaller collector area (360 m2) with a lower initial capital cost which is about 8% cheaper. Moreover, it produces higher annual energy at lower levelized cost of heat for solar multiples higher than 1. Carbon footprint of the factory would be reduced by about 114 tonnes CO2 annually. Sensible thermal energy storage technology can be considered for back up heat and heat recovery
Nature-Inspired Wind Farm Layout Optimization: Harnessing Smart Patterns for Sustainable Energy
No full textThis research investigates the transformative realm of wind farm layout optimization, with a specific focus on harnessing the efficiency of bio-inspired patterns. The positioning of wind turbine is play a vital role in the maximizing the energy output of a wind farm. If a wind turbine is placed in the wake region of the upstream turbine, the energy produced by the downstream turbine is reduced. Hence, it is imperative to place turbines in such a way that effect of the wake is minimum on a performance of turbines. The conventional grid-based approaches, commonly employed in wind farm layouts, face limitations in capturing the inherent complexity of wind flow dynamics, especially in varied terrains. In contrast, bio-inspired layouts, inspired by patterns observed in natural ecosystem, offer the promising results over the conventional Grid based approach. Our investigation involves the development and implementation of a novel bio-inspired wind farm layout positioning pattern. In the proposed approach, various nature inspired pattern like honeycomb and sunflower seeds pattern is explored for the turbine positioning. Further, the modeling of wind behavior includes both uniform wind speeds and variable wind speeds originating from all directions. The modified passing vehicle search (mPVS) optimization algorithm is used for optimizing the wind turbine placement. The results are obtained for the different wind scenario and compare it with the available results in the literature. The anticipated outcomes of this research include a deeper understanding of the potential benefits and challenges associated with bio-inspired wind farm layouts. The findings aim to contribute valuable insights into optimizing wind turbine placements, maximizing energy capture, and fostering sustainable practices in the wind energy sector. Results shows that the turbine positioning in the proposed bio-inspired pattern produce the higher power output (6%) compared to the conventional grid based approach. Hence, it can be concluded that the approach present in this study can assist wind farm designers and developers in optimally placing turbines for better performance
Impact of EU Funding on Latvian Aquaculture: Productivity, Competitiveness and Perspectives
No full textThe eligibility period for the 2014-2020 Operational Programme of the EU's European Maritime and Fisheries Fund (EMFF) closed at the end of 2023. The allocation under the EMFF to the Latvian fisheries and aquaculture sector was more than €130 million, distributed in accordance with Latvia's Fisheries Development Action Programme 2014-2020. The primary objective of this research is to analyse the outcomes attained through the allocation of funding and ascertain the extent to which Latvian aquaculture productivity has augmented, alongside its competitive standing and sustainability across both domestic and global markets. This includes integrating technological advances and innovative practices into existing aquaculture companies, as well as providing funding for projects that stimulate the creation of new aquaculture companies, such as the promotion of community-led local development strategies and the collection and availability of sector-specific data that could indirectly contribute to the development of the sector. A cost-effectiveness analysis was conducted to ascertain the anticipated return on the EU funding provided and evaluate the amplified growth prospects within the aquaculture sector. The results show that the performance indicators and targets set for the aquaculture sector as part of the funding allocation are vague and consequently do not lead to a recognisable increase in aquaculture productivity or added value
Editorial Introduction to Issue 40 of CSIMQ: Managing Different Forms of Complexity
No full textThe systems considered in the presented research can be characterized as dynamically complex open systems, which means that “the system’s coherence lies not only within the system itself but also in its relationship with the environment”. We can observe four forms of complexity: dynamic, architectural, relational, and generative. There is no doubt that modern complex systems combine these forms. By analyzing different datasets, the researchers deal with relational and dynamic complexity. If analysis is focused on organizing architectural principles, then we may talk about architectural and relational complexity. Trying to solve problems of uncertainty in processes, we face dynamic, architectural, and relational complexity. The adaptivity of systems tells us about their generative complexity. This journal issue is devoted to managing the architectural, dynamic, and relational complexity of the considered systems