The propeller state of unmanned aerial vehicles (UAV) is difficult to detect in real time due to trouble with laying out the sensor and multiple signal sources. To solve this problem, a fault detection method for multi-rotor UAV propellers was proposed based on a signal analysis of the built-in inertial measurement unit (IMU). Firstly, the multi-source coupled signals of the UAV flight were obtained through the ground station. Then, the picked-up signals were optimally separated according to the multi-rotor UAV propeller fault dynamics model, and signals rich in fault information were obtained. Finally, the separated signals were calculated using the symmetrized dot pattern (SDP), and then the similarity index was used to quantify the distribution of the signal in the feature plot to realize propeller fault detection. The OTSU algorithm was used to quantify the detection results, yielding a similarity of 76.2% in the z-axis direction, which is better than the values in the other two directions. The simulation and experimental analysis of the propeller failure dynamics model showed that the proposed method can effectively identify the propeller faults of multi-rotor UAVs.
Lahoucine Ech-Chatir, Salah Er-Raki, Julio Cesar Rodriguez
et al.
World food systems are subject to many challenges related to land degradation, rapid population growth, climate change, and limited resources. Crop growth models are being recognized as efficient tools for agricultural research to investigate trends in crop yield production and address these challenges under various pedoclimatic, genotypic, and management conditions. Crop growth models have come a long way in terms of development and use in recent decades but are still bound to be improved, especially for various perennial crops and the incorporation of beneficial soil microorganisms. Based on research papers published since 1965 across all continents, this review gives a brief history of crop models, explores 44 selected process-based crop growth models, their origin, usefulness, and applicability, and discusses some of their characteristics and their application in water management in arid and semi-arid areas. For the first time, this review highlights the modeling approaches in simulating the effects of beneficial soil microorganisms on crop growth, including plant growth-promoting rhizobacteria and mycorrhizal fungi, and discusses the advances in modeling perennial crops by exploring 35 studies found for fruit trees, perennial legumes, and vegetables, as well as 45 studies on perennial forage and bioenergy grasses. In addition, the review discusses crop modeling applications in the context of precision agriculture when combined with machine learning and remote sensing. The review concludes by emphasizing key limitations and challenges facing the use of crop growth models. Accordingly, this review can be a valuable resource for researchers, providing insights into existing crop models with a view to what needs to be improved.
Jackline W. Muturi, Christopher E. Ndehedehe, Mark J. Kennard
Accurate monitoring of irrigation water use (IWU) is essential for improving irrigation efficiency and countering global water stress. A key technique for monitoring IWU is satellite remote sensing, which observes the Earth ex-situ. This review synthesizes recent studies (2005–2024) to clarify the progress made and challenges in remote sensing of IWU, with a focus on global developments and specific emphasis on Australia, where vast geographic extent, regulatory complexity, and intensive irrigation pose unique challenges. Our objectives were to examine the relationships among methods, sensor types and measured variables, evaluate validation practices and identify study gaps in Australia. We found that studies have predominantly used optical sensors (82 %) to assess IWU while most other sensor types remain underutilized, particularly at regional scales, such as in Australia. Of the studies reviewed, 61 % validated their IWU estimates against field data, 24 % against reference data, 9 % against both reference and field data while 6 % did not perform validation. We highlight the need for strategic integration of remote sensing methods and sensor types to estimate IWU, supported by rigorous validation processes. Australia’s diverse agro-climatic landscape provides a valuable ground for evaluating and comparing different sensor types when used within various methods to estimate IWU. Furthermore, recent technological advances in optical, radar and microwave sensors, and future satellite missions present new opportunities in IWU monitoring. Overall, a coordinated approach within which policy makers are actively involved is essential for strengthening practical applicability of IWU estimates.
Photovoltaic-powered drip irrigation is a vital approach to address the irrigation requirements in regions with limited water resources and energy deficiencies, thereby ensuring the provision of sustenance and horticultural produce for local inhabitants. However, the susceptibility of the drip irrigation system to clogging as well as the fluctuations in photovoltaic output can significantly impact irrigation quality. Moreover, conventional storage methods commonly employed in photovoltaic-powered drip irrigation systems, such as elevated water tanks and batteries, exhibit notable technological, economic, and environmental limitations. The present study introduces a novel photovoltaic drip irrigation technology (CAES-PVDI) that utilizes solar energy as the exclusive source of power, enabling stable and cost-effective high-quality drip irrigation. This technology actively regulates solar energy through compressed air energy storage, employing a cyclic pulse discharge method to ensure uniformity in irrigation outflow and significantly enhance the anti-clogging performance of the drip irrigation system. The proposed technology was implemented in a solar greenhouse for drip irrigation, and subsequent tests were conducted to assess its hydraulic performance and anti-clogging properties The results demonstrated that the system achieved a discharge uniformity of no less than 91.76 %. Furthermore, there was no blocked emitter in CAES-PVDI system, and the sedimentation inside the capillary tube decreased by 78.95 %-93.36 % compared to traditional drip irrigation system. In comparison to existing photovoltaic-powered drip irrigation technology, the CAES-PVDI system exhibited exceptional technical indicators and offered significant economic and environmental benefits, thereby presenting a novel approach to promote environmentally friendly and efficient operation of drip irrigation systems.
Seok Jin Kwon, Jung Won Seo, Seong Kwang Hong
et al.
The surface of railway wheels running on rails is subject to damage due to rail and frictional wear, damage from wheel tread and flange wear caused by curved track operations, and damage from flats and concave wear due to braking friction heat from brake shoes. Although the surface of wheels is regularly reprofiled through periodic grinding cycles, damage occurring to the wheel surface during operation can lead to deteriorated ride quality and potential failure due to crack propagation. In domestic railway components technical standards, wheel integrity is mandated to be demonstrated through non-destructive testing. To prevent and detect failures caused by damage occurring on railway wheels, it is necessary to develop methods that could detect and evaluate surface damage. The present study investigated a method for detecting and evaluating surface damage on railway wheels using electromagnetic imaging. Results demonstrated that defects with a length of 10 mm, a width of 0.8 to 1.0 mm, and a depth of 0.2 to 1.0 mm could be adequately detected using electromagnetic scan images.
Usled potrebe za smanjenjem zagađenja životne sredine, usporavanja globalnog zagrevanja i sve manje količine raspoloživih fosilnih goriva, poslednjih godina svedočimo intenzivnom razvoju proizvodnje električne energije iz obnovljivih izvora, kao i razvoju tržišta električne energije. U okviru ovog rada biće izvršena uporedna analiza učesnika na tržištu električne energije u Crnoj Gori i Republici Srbiji, kao i njihovog uticaja na distributivni elektroenergetski sistem. Posebna pažnja biće posvećena kupcima-proizvođačima. Biće prikazani modeli obračuna električne energije kupaca-proizvođača i mogućnosti za njihove dodatne uštede kako energetske, tako i finansijske. Na kraju rada biće date preporuke za buduću lakšu integraciju kupaca-proizvođača i proizvođača električne energije iz obnovljivih izvora energije u distributivni elektroenergetski sistem kroz modele agregiranja, skladištenja i upravljanja proizvodnjom i potrošnjom
Energy industries. Energy policy. Fuel trade, Economics as a science
Elvis Dze Achuo, Honore Oumbe Tekam, Nembo Leslie Ndam
et al.
As regards the question whether natural resource affluence is a benediction or curse to sustainable development, the jury's verdict is still awaited. While we impatiently await the jury's verdict, this study provides empirical evidence that Mother Nature is responsible for Africa's predicaments with regard to economic development and environmental sustainability. Specifically, the system GMM estimates from 37 African economies reveal that: (i) natural resource affluence inhibits economic development, (ii) resource rents exacerbates carbon emissions thereby impeding environmental sustainability (iii) natural resource rents interacts with governance to produce negative synergy effects on economic growth and environmental pollution, (iv) resource rents interacts with ICT to produce respective positive net effects and negative synergy effects on economic growth and pollution emissions, (v) while non-renewable energy consumption inhibits economic growth and exacerbates pollution emissions, renewable energy consumption promotes environmental protection, (vi) we provide evidence of the U-shaped and inverted N-shaped EKC for natural resources, while also validating the inverted U-shaped EKC hypothesis relating to the nexus between per capita GDP and pollution emissions. Contingent on these findings, African countries can break the chains of the resource curse by designing sound and complementary policies upon attainment of the established thresholds by the policy modulating variables. Equally, various governments should strengthen governance quality and encourage digitalisation of the resource sector. Furthermore, African governments should propel the energy transition process by increasing investments in alternative clean energy sources in order to catalyse the attainment of the continent's Agenda 2063.
Oveis Hassanijalilian, C. Igathinathane, Stephanie Day
et al.
Iron deficiency chlorosis (IDC), a symptom of reduction in chlorophyll and stunted growth, causes a great yield loss in soybean every year in the Midwest, USA and the most efficient method to manage IDC is to plant tolerant cultivars. The assessment of cultivars' tolerance is traditionally performed by visually rating the IDC symptoms based on leaves discoloration twice during the growing season. However, the visual rating method is time-consuming, subjective, not suitable at large scales, labor-intensive, and unaffordable for frequent observation. Therefore, in this study, we used an unmanned aerial vehicle (UAV) as a tool to monitor the soybean cultivars more frequently and more efficiently through image processing approach of the whole field. Images were taken with a DJI Phantom 4 and orthomosaicked in Agisoft Photoscan. A 40-cultivar soybean experimental plots (3000 m2; Image 1) at 5 locations in North Dakota, USA (Amenia, Colfax, Leonard (2), and Hunter) for 2 years (2016 and 2017) were used in the study. The orthomosaicked images were processed in MATLAB to calculate the dark green color index (DGCI), which is a good indicator of chlorophyll in soybean leaves. The grayscale DGCI images were then processed in ArcGIS to extract the average DGCI and canopy size (CS) for each plot for each flight. The area under the curve (AUC) was calculated for DGCI, CS, and CS × DGCI product (CDP) to aggregate the values of all flights within each year. The correlation of AUC of CDP and the yield was more consistent among both years and was the better predictor of yield (R2=0.74 and R2=0.79). The latest growth stage (more representative of yield) values of both years were combined to build models for yield prediction and the CDP produced the lowest error (11.72%). Future studies should look into IDC progress measurement involving more cultivars, geographical locations, frequent imaging, as well as methods applied to regular soybean production sites to evaluate various image-based parameters and their interaction for yield predictions.
Substrate-grown crops represent approximately 10% of the cropping area of intensive greenhouse horticulture in southern Spain. The vast majority are free draining, in that they do not collect and recirculate drainage. The substantial nutrient loss in drainage contributes to contamination of water bodies. This study examined the effectiveness of dynamic management approaches to appreciably reduce the large nutrient loss associated with free-draining substrate-grown crops. For three tomato crops, grown in substrate, this study (i) compared management of N, P and K based on the ratio of the concentration in drainage to that in the nutrient solution, to conventional management, (ii) derived uptake concentration values for N, P and K throughout the crop cycle, and (iii) evaluated uptake concentration as a nutrition management tool. Ratio-based management reduced the amounts of N, P and K in drainage, in relation to conventional management by 58–61%, 65–80% and 55–77% respectively. The amounts of applied N, P and K were reduced by 22–28%, 37–43%, and 28–34% compared to conventional management. N, P and K concentrations in the applied nutrient solution slightly below the uptake concentration were associated with much lower concentrations in the drainage solution. In contrast, when the applied nutrient concentration exceeded the uptake concentration this was associated with much higher drainage nutrient concentrations. In conclusion, the two nutritional management strategies examined, ratio-based management, and use of uptake concentrations were both associated with reduced nutrient application and a considerable reduction of nutrient loss in drainage. Fruit production was maintained with the improved nutrient management practices. These strategies offer approaches that can considerably reduce the substantial nutrient loss in drainage associated with free-draining substrate cropping in greenhouse production in southern Europe.
Abstract Data integration in the energy sector, which refers to the process of combining and harmonizing data from multiple heterogeneous sources, is becoming increasingly difficult due to the growing volume of heterogeneous data. Schema matching plays a crucial role in this process by giving each representation a unique identity by matching raw energy data to a generic data model. This study uses an energy domain language model to automate schema matching, reducing manual effort in integrating heterogeneous data. We developed two energy domain language models, Energy BERT and Energy Sentence Bert, and trained them using an open-source scientific corpus. The comparison of the developed models with the baseline model using real-life energy domain data shows that Energy BERT and Energy Sentence Bert models significantly improve the accuracy of schema matching.
Amanda dos Santos Teles Cardoso, Marcelo Tavares Pereira, Cinara Vasconcelos da Silva
et al.
Introdução: O medicamento tem natureza híbrida, ou seja, promove benefícios à saúde, mas também portam riscos. O acompanhamento farmacoterapêutico, atividade ofertada aos pacientes em tratamento da Hepatite C, beneficiários de um plano de saúde para servidores públicos conveniado com a Farmácia da Universidade, tem se revelado uma ferramenta importante para o uso racional de medicamentos e o alcance de bons resultados com a farmacoterapia, principalmente em pacientes com condições crônicas. Objetivo: Descrever o perfil do paciente e os problemas relacionados com medicamento, identificando as intervenções propostas pela equipe de farmacêuticos os resultados alcançados. Métodos: As informações foram obtidas dos formulários de acompanhamento farmacoterapêutico utilizados no atendimento ao paciente no ano de 2017. Todo registro clínico foi feito nos moldes da metodologia SOAP, com adaptações. Resultados: Paciente do sexo feminino, 54 anos, diagnosticada com Hepatite C (F1), câncer de crânio com metástase óssea e câncer de pulmão primário, em uso de 10 (dez) medicamentos prescritos, incluindo medicamentos paliativos, anticonvulsivante, quimioterapia e chá por automedicação, com indicação tratamento da Hepative C com daclatasvir e sofosbovir. A partir da análise dos medicamentos utilizados foi identificado 1 (um) problema relacionado ao medicamento, 1 (uma) interação medicamentosa importante, 1 (um) problema de adesão aos medicamentos e reações adversas medicamentosas decorrentes do uso do anticonvulsivante e da quimioterapia. O aprazamento dos medicamentos em uso pela paciente foi readequado, sendo também sugeridas ao prescritor e acatadas duas substituições do medicamento anticonvulsivante (uma por interação medicamentosa e outra por reação adversa). DISCUSSÃO: O conhecimento sobre interação das drogas antivirais de ação direta com as utilizadas no tratamento paliativo do câncer metastático são pouco robustos. A revisão do aprazamento facilitou da administração dos medicamentos, a substituição do anticonvulsivante e suspensão do uso de chá preveniu a ocorrência de interação medicamentosa e contribuiu no aumento da adesão. Conclusão: o acompanhamento farmacoterapêutico dispensado à paciente demonstrou-se relevante, pois possibilitou prevenir a ocorrência de problemas relacionados aos medicamentos como eventos adversos e interações medicamentosas, evidenciando a importância da relação farmacêutico/paciente.
Pharmacy and materia medica, Pharmaceutical industry
Abstract Background Naval traffic is highly dependent on depleting fossil resources and causes significant greenhouse gas emissions. At the same time, marine transportation is a major backbone of world trade. Thus, alternative fuel concepts are highly needed. Different fuels such as ammonia, methanol, liquefied natural gas and hydrogen have been proposed. For some of them, first prototype vessels have been in operation. However, practical experience is still limited. Most studies so far focus on aspects such as efficiency and economics. However, particularly in marine applications, reliability of propulsion systems is of utmost importance, because failures on essential ship components at sea pose a huge safety risk. If the respective components lose their functionality, repair can be much more challenging due to large distances to dockyards and the complicated transport of spare parts to the ship. Consequently, evaluation of reliability should be a core element of system analysis for new marine fuels. Results In this study, reliability was studied for four potential fuels. The analysis involved several steps: estimation of overall failure rates, identification of most vulnerable components and assessment of criticality by including severity of fault events. On the level of overall failure rate, ammonia is shown to be very promising. Extending the view over a pure failure rate-based evaluation shows that other approaches, such as LOHC or methanol, can be competitive in terms of reliability and risk. As different scenarios require different weightings of the different reliability criteria, the conclusion on the best technology can differ. Relevant aspects for this decision can be the availability of technical staff, high-sea or coastal operation, the presence of non-naval personnel onboard and other factors. Conclusions The analysis allowed to compare different alternative marine fuel concepts regarding reliability. However, the analysis is not limited to assessment of overall failure rates, but can also help to identify critical elements that deserve attention to avoid fault events. As a last step, severity of the individual failure modes was included. For the example of ammonia, it is shown that the decomposition unit and the fuel cell should be subject to measures for increasing safety and reducing failure rates.
Renewable energy sources, Energy industries. Energy policy. Fuel trade
Abstract With the advent of the smart grid era, the electrical grid is becoming a complex network in which different technologies coexist to bring benefits to both customers and operators. This paper presents a methodology for analyzing Key Performance Indicators (KPIs), providing knowledge about the performance and efficiency of energy systems, focusing on the demand side. In the first stage of the methodology, the baseline KPIs are calculated. In the second stage, all KPIs are updated to be compared with the baseline ones. In fact, due to the dynamic nature of players in a smart grid, this methodology plays a crucial role in the performance assessment. Moreover, the proper definition and selection of KPIs is usually a challenging task since KPIs can be applied to evaluate diverse areas within a smart grid. Such areas include building energy efficiency, home communications, and smart metering deployment, just to mention a few. In the proposed methodology, the information obtained from a KPI can be driven to distinct aspects such as efficiency, environment, reliability, power quality, safety, security, or cost reduction. Through a case study from a real implementation of an energy system, we show how to assess energy consumption efficiency, thus improving energy management.
Alexander Vladimirovich Litvinov, Vadim Valerianovich Donchenko
In order to plan and predict the development of urban transport systems, it is necessary to understand the relationships between car ownership and car usage indicators for various options of urban transport policy.
The purpose of the study was to examine the relationship between car ownership and share of trips on passenger cars within the framework of the conventional approach to transport systems development and the approach based on the concept of sustainable development.
Materials and methods. The methods of regression analysis were used to build the dependencies between car ownership and share of trips on passenger cars in cities. The dependencies were built on the basis of synthesis the urban mobility studies results in some cities of Russia, Eastern and Western Europe over the past fifty years.
Results. The share of trips on passenger cars increases with the increase of car ownership. The dependence is well described by the logistic curve. The approach based on the concept of sustainable development is associated with a targeted reduction in the share of trips on passenger cars. The analysis shows that car ownership decreases with a decrease in the share of trips on passenger cars, but such decrease occurs with a delay. There is a hysteresis phenomenon.
Practical implications. The results of the study help to better understand the changes in the travel behavior associated with car ownership and using a car, depending on the transport policy being pursued.
The aim of the paper is to identify elements of seasonality in supply and demand in the liquid biofuels sector in Poland and Germany. An additional purpose is to present forecasts for selected aggregates until 2020. Two research questions have been formulated for their implementation: (1) is biofuel production in Poland higher in spring or summer (due to the seasonality of agricultural raw material production) than e.g. in winter?; (2) Is the consumption of biofuels seasonal in both countries? The research applies quarterly data for the following aggregates from the biofuels sector: for Poland – production and sale of biofuels in the quarters of 2006-2018, for Germany – biofuel consumption in the quarters of 2007-2017, import and export of bioethanol in the quarters of 2007-2015, import and export of esters in the quarters of 2007-2017. The work focuses on identifying seasonal fluctuations in order to identify purified seasonality indicators, so that it is possible to present forecasts for the biofuels sector. The research conducted in the article leads to the conclusions that, in the liquid biofuels sector, in Poland and Germany, there are elements of seasonality, especially in the field of sales / consumption of biofuels, which in turn is the effect of the changing demand for traditional fuels in which liquid biocomponents are admixed or (less often) used separately as fuel. Differences in the values of variables in Poland and Germany in quarters, in the analysed periods, can be significant – they usually reach several dozen (up to even over 100%), although in nominal terms these differences are usually several or several percentage points. The consumption of biofuels in both countries was higher in the second and third quarters, i.e. in the spring-summer period than others.
The problem of the analytical synthesis of the synergetic control system of chemical reactor for the realization of a complex series-parallel exothermal reaction has been solved. The synthesis of control principles is performed using the analytical design method of aggregated regulators. Synthesized nonlinear control system solves the problem of stabilization of the concentration of target component at the exit of reactor and also enables one to automatically transfer to new production using the equipment.
The paper discusses the characteristics of scattering of electromagnetic waves on the angular diffraction structures. The solution of the problem is based on the method of integral equations. A comparative analysis of the scattering characteristics of structures with different shape is carried out.
Marcio Marconato, Marcos Aurélio Brambilla, Sidnei Pereira do Nascimento
et al.
O objetivo do presente artigo é verificar a existência da relação espacial entre o beneficio médio concedido pelo Programa Bolsa Família e a taxa de pobreza nos municípios do estado de Santa Catarina. A metodologia utilizada foi a Análise Exploratória dos Dados Espaciais (AEDE). Os resultados revelam a existência da autocorrelação espacial positiva entre as variáveis estudadas, pois os municípios que apresentaram elevado (Baixo) repasse médio do programa Bolsa Família estão rodeados por municípios com grande (Baixo) valor do repasse médio do Programa Bolsa Família. O coeficiente I de Moran positivo indica a existência de autocorrelação positiva entre o valor médio repassado do Programa Social Bolsa Família e a taxa de pobreza, ou seja, onde a pobreza é maior o benéfico médio também é maior. Foi observado um cluster alto-alto na região Oeste e Norte e um baixo-baixo na região Leste e Central.