Search results for: stochastic demand

Authors: Sami M. Alshareef

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The rapid growth of smart grid technology has brought significant advancements to the power industry. However, with the increasing interconnectivity and reliance on information and communication technologies, smart grids have become vulnerable to cyber-attacks, posing significant threats to the reliable operation of power systems. Among the critical components of smart grids, the Automatic Generation Control (AGC) system plays a vital role in maintaining the balance between generation and load demand. Therefore, protecting the AGC system from cyber threats is of paramount importance to maintain grid stability and prevent disruptions. Traditional security measures often fall short in addressing sophisticated and evolving cyber threats, necessitating the exploration of innovative approaches. Machine learning, with its ability to analyze vast amounts of data and learn patterns, has emerged as a promising solution to enhance AGC system security. Therefore, this research proposal aims to address the challenges associated with detecting and mitigating cyber-attacks on AGC in smart grids by leveraging machine learning techniques on automatic generation control of two-area power systems. By utilizing historical data, the proposed system will learn the normal behavior patterns of AGC and identify deviations caused by cyber-attacks. Once an attack is detected, appropriate mitigation strategies will be employed to safeguard the AGC system. The outcomes of this research will provide power system operators and administrators with valuable insights into the vulnerabilities of AGC systems in smart grids and offer practical solutions to enhance their cyber resilience.

Keywords: machine learning, cyber-attacks, automatic generation control, smart grid

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Authors: Tukur Daiyabu Abdulkadir, Wan Ishak Wan Ismail, Muhammad Saufi Mohd Kassim

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Seed singulation and accuracy in seed spacing are the major challenges associated with the adoption of mechanical seeder for system of rice intensification. In this research the metering system of a pneumatic planter was modified and automated for increase precision to meet the demand of system of rice intensification SRI. The chain and sprocket mechanism of a conventional vacuum planter were now replaced with an electro mechanical system made up of a set of servo motors, limit switch, micro controller and a wheel divided into 10 equal angles. The circumference of the planter wheel was determined based on which seed spacing was computed and mapped to the angles of the metering wheel. A program was then written and uploaded to arduino micro controller and it automatically turns the seed plates for seeding upon covering the required distance. The servo motor was calibrated with the aid of labVIEW. The machine was then calibrated using a grease belt and varying the servo rpm through voltage variation between 37 rpm to 47 rpm until an optimum value of 40 rpm was obtained with a forward speed of 5 kilometers per hour. A pressure of 1.5 kpa was found to be optimum under which no skip or double was recorded. Precision in spacing (coefficient of variation), miss index, multiple index, doubles and skips were investigated. No skip or double was recorded both at laboratory and field levels. The operational parameters under consideration were both evaluated at laboratory and field. Even though there was little variation between the laboratory and field values of precision in spacing, multiple index and miss index, the different is not significant as both laboratory and field values fall within the acceptable range.

Keywords: automation, calibration, pneumatic seed planter, system of rice intensification

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Authors: Rubens Duarte Coelho, Timóteo Herculino da Silva Barros, Jefferson de Olveira Costa

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Brazil has an electrical matrix of predominantly renewable origin, with emphasis on water sources, which account for 65.2%, biomass energy for 8.2%, wind for 6.8% and solar for 0.13% of the domestic supply. Among these sources, sugarcane cultivation stands out, aiming both at the production of bioethanol and biomass to supply “clean energy”. However, like all other crops, sugar cane demands a large volume of a natural resource that is increasingly “scarce” in quantity and quality: water. Adequate and strategic water management throughout the entire sugarcane cycle is of fundamental importance, and water productivity can be used to adjust irrigation planning and decision-making, increasing the productivity of stalks, bioethanol, biomass, and sugar. In this way, water productivity is a good indicator for analysis and decision-making considering the sustainability of cultivation, as it allows evaluation of the variation in the ratio between production and the amount of water used, suggesting values that maximize the use of this natural resource. In this context, studies that relate water demand, in this case, expressed by water productivity, with the energy production of this crop, in this case, expressed by the production of bioethanol, biomass and sugar, are fundamental to obtaining an efficient production of renewable energy, which aims at the rational use of natural resources, especially water. The objective of the present work was to evaluate the response of sugarcane varieties subjected to different water availability to obtain better sustainability in bioenergy production, presenting water productivity indices for Bioethanol, Sugar and Biomass. The variety that responded best was RB966928, with a bioethanol yield of 68.7 L Mg-1. Future research should focus on the water response under each of the sugarcane fractions in terms of their elemental composition so that the influence of water on the energy supply of this crop can be better understood.

Keywords: energy matrix, water use, water use efficiency, sustainability

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Authors: Omar Bouledroua, Djamel Zelmati, Zahreddine Hafsi, Milos B. Djukic

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Transporting hydrogen gas through the existing natural gas pipeline network offers an efficient solution for energy storage and conveyance. Hydrogen generated from excess renewable electricity can be conveyed through the API 5L steel-made pipelines that already exist. In recent years, there has been a growing demand for the transportation of hydrogen through existing gas pipelines. Therefore, numerical and experimental tests are required to verify and ensure the mechanical integrity of the API 5L steel pipelines that will be used for pressurized hydrogen transportation. Internal pressure loading is likely to accelerate hydrogen diffusion through the internal pipe wall and consequently accentuate the hydrogen embrittlement of steel pipelines. Furthermore, pre-cracked pipelines are susceptible to quick failure, mainly under a time-dependent cyclic pressure loading that drives fatigue crack propagation. Meanwhile, after several loading cycles, the initial cracks will propagate to a critical size. At this point, the remaining service life of the pipeline can be estimated, and inspection intervals can be determined. This paper focuses on the hydrogen embrittlement of API 5L steel-made pipeline under cyclic pressure loading. Pressurized hydrogen gas is transported through a network of pipelines where demands at consumption nodes vary periodically. The resulting pressure profile over time is considered a cyclic loading on the internal wall of a pre-cracked pipeline made of API 5L steel-grade material. Numerical modeling has allowed the prediction of fatigue crack evolution and estimation of the remaining service life of the pipeline. The developed methodology in this paper is based on the ASME B31.12 standard, which outlines the guidelines for hydrogen pipelines.

Keywords: hydrogen embrittlement, pipelines, transient flow, cyclic pressure, fatigue crack growth

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Authors: P. F. Msomi, P. T. Nonjola, P. G. Ndungu, J. Ramontja

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In view of the projected global energy demand and increasing levels of greenhouse gases and pollutants issues have inspired an intense search for alternative new energy technologies, which will provide clean, low cost and environmentally friendly solutions to meet the end user requirements. Alkaline anion exchange membrane fuel cells (AAEMFC) have been recognized as ideal candidates for the generation of such clean energy for future stationary and mobile applications due to their many advantages. The key component of the AAEMFC is the anion exchange membrane (AEM). In this report, a series of quaternized poly (2.6 dimethyl – 1.4 phenylene oxide)/ polysulfone (QPPO/PSF) blend anionic exchange membranes (AEM) were successfully fabricated and characterized for alkaline fuel cell application. Zinc Oxide (ZnO) nanoparticles were introduced in the polymer matrix to enhance the intrinsic properties of the AEM. The characteristic properties of the QPPO/PSF and QPPO/PSF-ZnO blend membrane were investigated with X-ray diffraction (XRD), thermogravimetric analysis (TGA) scanning electron microscope (SEM) and contact angle (CA). To confirm successful quaternisation, FT-IR spectroscopy and proton nuclear magnetic resonance (1H NMR) were used. Other properties such as ion exchange capacity (IEC), water uptake, contact angle and ion conductivity (IC) were also undertaken to check if the prepared nanocomposite materials are suitable for fuel cell application. The membrane intrinsic properties were found to be enhanced by the addition of ZnO nanoparticles. The addition of ZnO nanoparticles resulted to a highest IEC of 3.72 mmol/g and a 30-fold IC increase of the nanocomposite due to its lower methanol permeability. The above results indicate that QPPO/PSF-ZnO is a good candidate for AAEMFC application.

Keywords: anion exchange membrane, fuel cell, zinc oxide nanoparticle, nanocomposite

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Authors: Umme Habiba Jasmine, Mzikazi Nduna

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Due to the dearth of exploratory research in Bangladesh on parenting practices and transmission thereof, there is a lack of information on culture-sensitive methodology in studying this topic. This paper aims to share some methodological reflections from the research field, which will address this knowledge gap. Eleven dyads of biological mothers and maternal grandmothers of school-going children constituted the sample, and a female fieldworker conducted one-to-one, semi-structured, in-depth interviews with them. The participants were recruited through purposive sampling through a representative of a cooperative society in Mirpur area in Bangladesh. Four dyads of the sample outside that eleven dyads were discarded because of the unavailability of the other participant of the dyads or unsuitability for an in-depth interview. The sample recruitment strategy of approaching mothers without their known reference body had to be discarded because of existing social insecurity in Dhaka city. To meet the cultural demand of the research field the researcher had to change in the research plan and comply with the cultural tradition of mutual entertainment with food while conducting interviews which helped in engaging in positive interaction. Also, the researcher had to compromise the strict confidentiality to a collectivistic sense of confidentiality of the in-depth interview sessions. This study suggests future researchers to investigate Bangladeshi traditional practices and accommodate the applicable ones in their research plan for qualitative studies, especially the Bengali tradition of hospitality and shared confidentiality for building rapport and for proper access to the targeted information and research participants. Sample recruitment should always accompany a well-accepted reference person in the targeted research field.

Keywords: confidentiality, culture-sensitive, ethics, parenting practices, sampling

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Authors: W. Swiderski

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Composite materials are one answer to the growing demand for materials with better parameters of construction and exploitation. Composite materials also permit conscious shaping of desirable properties to increase the extent of reach in the case of metals, ceramics or polymers. In recent years, composite materials have been used widely in aerospace, energy, transportation, medicine, etc. Fiber-reinforced composites including carbon fiber, glass fiber and aramid fiber have become a major structural material. The typical defect during manufacture and operation is delamination damage of layered composites. When delamination damage of the composites spreads, it may lead to a composite fracture. One of the many methods used in non-destructive testing of composites is active infrared thermography. In active thermography, it is necessary to deliver energy to the examined sample in order to obtain significant temperature differences indicating the presence of subsurface anomalies. To detect possible defects in composite materials, different methods of thermal stimulation can be applied to the tested material, these include heating lamps, lasers, eddy currents, microwaves or ultrasounds. The use of a suitable source of thermal stimulation on the test material can have a decisive influence on the detection or failure to detect defects. Samples of multilayer structure carbon composites were prepared with deliberately introduced defects for comparative purposes. Very thin defects of different sizes and shapes made of Teflon or copper having a thickness of 0.1 mm were screened. Non-destructive testing was carried out using the following sources of thermal stimulation, heating lamp, flash lamp, ultrasound and eddy currents. The results are reported in the paper.

Keywords: Non-destructive testing, IR thermography, composite material, thermal stimulation

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Authors: Michael Wright, Tiago Costa

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The construction industry in SE Asia has been relying on S355 MPa “as rolled” H-beams for many years now. It is an easily sourced, metallurgically simple, reliable product that all designers, fabricators and constructors are familiar with. However, as the Global demand to better use our finite resources gets stronger, the need for an as-rolled S460 MPa H-Beam is becoming more apparent. The Financial benefits of an “as-rolled” S460 MPa H-beam are obvious. The S460 MPa beam which is currently available and used is fabricated from rolled strip. However, making H-beam from 3 x 460 MPa strips requires costly equipment, valuable welding skills & production time, all of which can be in short supply or better used for other purposes. The Metallurgical benefits of an “as-rolled” S460 MPa H-beam are consistency in the product. Fabricated H-beams have inhomogeneous areas where the strips have been welded together - parent metal, heat affected zone and weld metal all in the one body. They also rely heavily on the skill of the welder to guarantee a perfect, defect free weld. If this does not occur, the beam is intrinsically flawed and could lead to failure in service. An as-rolled beam is a relatively homogenous product, with the optimum strength and ductility produced by delivering steel with as fine as possible uniform cross sectional grain size. This is done by cost effective alloy design coupled with proper metallurgical process control implemented into an existing mill’s equipment capability and layout. This paper is designed to highlight the benefits of bring an “as-rolled” S460 MPa H-beam to the construction market place in SE Asia, and hopefully encourage the current “as-rolled” H-beam producers to rise to the challenge and produce an innovative high quality product for the local market.

Keywords: fine grained, As-rolled, long products, process control, metallurgy

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Authors: Tom Ryan

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This paper investigates the rural mobility and accessibility challenges of a specific target group - Seniors. The target group is those over 66 years of age who are entitled to use the Public Transport (PT) Free Travel Scheme in rural Ireland. The paper explores at a high level some of the projected rural PT challenges and requirements over the next 10-15 years, noting that statistical predictions show that there will be a significant population demographic shift within the Senior's age profile. Using the PESTEL framework, the literature review explored existing research concerning mobility, accessibility challenges, and the opportunities Seniors face. Twenty-seven qualitative in-depth interviews with stakeholders within the ecosystem were undertaken. The stakeholders included: rural PT customers, Local-Link managers, NTA senior management, a Minister of State, and a European parliament policymaker. Tier 1 interviewee feedback spotlights that the PT network system does not exist for rural patients to access hospital facilities. There was no evidence from the Tier 2 research findings to show that health policymakers and transport planners are working to deliver a national solution to support patients getting access to hospital appointments. Several research interviewees discussed the theme of isolation and the perceived stigma of senior males utilising PT. The findings indicated that MaaS is potentially revolutionary in the PT arena. Finally, this paper suggests several short-, medium- and long-term recommendations based on the research findings. These recommendations are a potential springboard to ensure that rural PT is suitable for future Irish generations.

Keywords: accessibility, active ageing, car dependence, isolation, seniors health issues, behavioural changes, environmental challenges, internet of things, demand responsive, mobility as a service

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Authors: Tamar Lazariashvili

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Introduction: The agro-insurance has great importance for agricultural development in the country. In the article, the insurance market of the Georgian agricultural sector has been studied, the level of interest of farmers with insurance products and the trend of demand for those products are revealed; also, the importance of insurance is substantiated. Methodology: The following research methods are applied in the presented paper: statistical (selection, grouping, observation, trend) and qualitative research (in-depth interview with farmers). They claim that the main reason for aggravation is the low level of trust, less awareness about the conditions of the insurance contract. In order to eradicate distrust towards agro-insurance, it is recommended to increase awareness of insured farmers in terms of an insurance agreement. In the case of disputable issues between insurance companies and the customers (farmers), it is advisable to enact the Mediation Service, which will be able to protect the rights of insured farmers. Main Findings: Insurance companies prefer to deal with large farmers, the number of them is very small in Georgia as the credit market. The government interference in this sector is also a very cautious topic. However, the government can strengthen the awareness of farmers about the characteristics and advantages of the insurance system in order to increase the number of insured and reduce insurance premiums for farmers. Conclusion: Enactment of agro-insurance will increase the interest and confidence of financial institutions in the farming sector, financial resources will be accessible to the farmers that will facilitate the stable development of the sector in the country. The size of the agro-insurance market in the country should be increased, and the new territories should be covered. The State must have an obligation to ensure the risk of farmers and subsidize insurance companies. Based on the analysis of the insurance market, the conclusions on agro-insurance issues and the relevant recommendations are proposed.

Keywords: Agro-insurance, agricultural product, Agro-market, farming

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Authors: Mahmoud Almasri, Xavier Marjou, Fanny Parzysz

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The demand for services provided by Unmanned Aerial Vehicles (UAVs) is increasing pervasively across several sectors including potential public safety, economic, and delivery services. As the number of applications using UAVs grows rapidly, more and more powerful, quality of service, and power efficient computing units are necessary. Recently, cellular technology draws more attention to connectivity that can ensure reliable and flexible communications services for UAVs. In cellular technology, flying with a high speed and altitude is subject to several key challenges, such as frequent handovers (HOs), high interference levels, connectivity coverage holes, etc. Additional HOs may lead to “ping-pong” between the UAVs and the serving cells resulting in a decrease of the quality of service and energy consumption. In order to optimize the number of HOs, we develop in this paper a Q-learning-based algorithm. While existing works focus on adjusting the number of HOs in a static network topology, we take into account the impact of cells deployment for three different simulation scenarios (Rural, Semi-rural and Urban areas). We also consider the impact of the decision distance, where the drone has the choice to make a switching decision on the number of HOs. Our results show that a Q-learning-based algorithm allows to significantly reduce the average number of HOs compared to a baseline case where the drone always selects the cell with the highest received signal. Moreover, we also propose which hyper-parameters have the largest impact on the number of HOs in the three tested environments, i.e. Rural, Semi-rural, or Urban.

Keywords: drones connectivity, reinforcement learning, handovers optimization, decision distance

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Authors: Rian O. Miranda, Lidia V. de Sa, Julio C. Suita

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The Brazilian Nuclear Energy Commission (CNEN) is the main manufacturer of radiopharmaceuticals in Brazil. The Nuclear Engineering Institute (IEN), located at Rio de Janeiro, is one of its main centers of research and production, attending public and private hospitals in the state. This radiopharmaceutical production is used in diagnostic and therapy procedures and allows one and a half million nuclear medicine procedures annually. Despite this, the country is not self-sufficient to meet national demand, creating the need for importation and consequent dependence on other countries. However, IEN facilities were designed in the 60's, and today its structure is inadequate in relation to the good manufacturing practices established by sanitary regulator (ANVISA) and radiological protection leading to the need for a new project. In order to adapt and increase production in the country, a new plant will be built and integrated to the existing facilities with a new 30 MeV Cyclotron that is actually in project detailing process. Thus, it is proposed to survey current CNEN and ANVISA standards for radiopharmaceutical production facilities, as well as the radiological protection analysis of each area of the plant, following good manufacturing practices recommendations adopted nationally besides licensing exigencies for radioactive facilities. In this way, the main requirements for proper operation, equipment location, building materials, area classification, and maintenance program have been implemented. The access controls, interlocks, segregation zones and pass-through boxes integrated into the project were also analyzed. As a result, IEN will in future have the flexibility to produce all necessary radioisotopes for nuclear medicine application, more efficiently by simultaneously bombarding two targets, allowing the simultaneous production of two different radioisotopes, minimizing radiation exposure and saving operating costs.

Keywords: cyclotron, legislation, norms, production, radiopharmaceuticals

Procedia PDF Downloads 135

Authors: P. Valsalal, S. Thangalakshmi

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There is a widespread changeover in the electrical power industry universally from old-style monopolistic outline towards a horizontally distributed competitive structure to come across the demand of rising consumption. When the transmission lines of derestricted system are incapable to oblige the entire service needs, the lines are overloaded or congested. The governor between customer and power producer is nominated as Independent System Operator (ISO) to lessen the congestion without obstructing transmission line restrictions. Among the existing approaches for congestion management, the frequently used approaches are reorganizing the generation and load curbing. There is a boundary for reorganizing the generators, and further loads may not be supplemented with the prevailing resources unless more private power producers are added in the system by considerably raising the cost. Hence, congestion is relaxed by appropriate Flexible AC Transmission Systems (FACTS) devices which boost the existing transfer capacity of transmission lines. The FACTs device, namely, Unified Power Flow Controller (UPFC) is preferred, and the correct placement of UPFC is more vital and should be positioned in the highly congested line. Hence, the weak line is identified by using power flow performance index with the new objective function with proposed hybrid Fish – Bee algorithm. Further, the location of UPFC at appropriate line reduces the branch loading and minimizes the voltage deviation. The power transfer capacity of lines is determined with and without UPFC in the identified congested line of IEEE 30 bus structure and the simulated results are compared with prevailing algorithms. It is observed that the transfer capacity of existing line is increased with the presented algorithm and thus alleviating the congestion.

Keywords: available line transfer capability, congestion management, FACTS device, Hybrid Fish-Bee Algorithm, ISO, UPFC

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Authors: Girts Bumanis, Diana Bajare

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With demand for primary energy continuously growing, search for renewable and efficient energy sources has been high on agenda of our society. One of the most promising energy sources is biogas technology. Residues coming from dairy industry and milk processing could be used in biogas production; however, low efficiency and high cost impede wide application of such technology. One of the main problems is management and conversion of organic residues through the anaerobic digestion process which is characterized by acidic environment due to the low whey pH (<6) whereas additional pH control system is required. Low buffering capacity of whey is responsible for the rapid acidification in biological treatments; therefore alkali activated material is a promising solution of this problem. Alkali activated material is formed using SiO2 and Al2O3 rich materials under highly alkaline solution. After material structure forming process is completed, free alkalis remain in the structure of materials which are available for leaching and could provide buffer capacity potential. In this research porous alkali activated material was investigated. Highly porous material structure ensures gradual leaching of alkalis during time which is important in biogas digestion process. Research of mixture composition and SiO2/Na2O and SiO2/Al2O ratio was studied to test the buffer capacity potential of alkali activated material. This research has proved that by changing molar ratio of components it is possible to obtain a material with different buffer capacity, and this novel material was seen to have considerable potential for using it in processes where buffer capacity and pH control is vitally important.

Keywords: alkaline material, buffer capacity, biogas production, bioreactors

Procedia PDF Downloads 242

Authors: Javkhlan Nyamjav, Simona Fischer, Lauren Garner, Veronica McCracken

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Current whole building life cycle assessments (LCA) primarily focus on structural and major architectural elements to measure building embodied carbon. Most of the interior finishes and fixtures are available on digital tools (such as Tally); however, furniture is still left unaccounted for. Due to its repeated refreshments and its complexity, furniture embodied carbon can accumulate over time, becoming comparable to structure and envelope numbers. This paper presents a method to calculate the Global Warming Potential (GWP) of furniture elements in commercial buildings. The calculator uses the quantity takeoff method with GWP averages gathered from environmental product declarations (EPD). The data was collected from EPD databases and furniture manufacturers from North America to Europe. A total of 48 GWP numbers were collected, with 16 GWP coming from alternative EPD. The finalized calculator shows the average GWP of typical commercial furniture and helps the decision-making process to reduce embodied carbon. The calculator was tested on MSR Design projects and showed furniture can account for more than half of the interior embodied carbon. The calculator highlights the importance of adding furniture to the overall conversation. However, the data collection process showed a) acquiring furniture EPD is not straightforward as other building materials; b) there are very limited furniture EPD, which can be explained from many perspectives, including the EPD price; c) the EPD themselves vary in terms of units, LCA scopes, and timeframes, which makes it hard to compare the products. Even though there are current limitations, the emerging focus on interior embodied carbon will create more demand for furniture EPD. It will allow manufacturers to represent all their efforts on reducing embodied carbon. In addition, the study concludes with recommendations on how designers can reduce furniture-embodied carbon through reuse and closed-loop systems.

Keywords: furniture, embodied carbon, calculator, tenant improvement, interior design

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Authors: Nousheen Hashmi, Shoab Ahmad Khan

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Active collaboration among the green energy sources and the load demand leads to serious issues related to power quality and stability. The growing number of green energy resources and Distributed-Generators need newer strategies to be incorporated for their operations to keep the power energy stability among green energy resources and micro-grid/Utility Grid. This paper presents a novel technique for energy power management in Grid-Connected Photovoltaic with energy storage system under set of constraints including weather conditions, Load Shedding Hours, Peak pricing Hours by using rule-based fuzzy smart grid controller to schedule power coming from multiple Power sources (photovoltaic, grid, battery) under the above set of constraints. The technique fuzzifies all the inputs and establishes fuzzify rule set from fuzzy outputs before defuzzification. Simulations are run for 24 hours period and rule base power scheduler is developed. The proposed fuzzy controller control strategy is able to sense the continuous fluctuations in Photovoltaic power generation, Load Demands, Grid (load Shedding patterns) and Battery State of Charge in order to make correct and quick decisions.The suggested Fuzzy Rule-based scheduler can operate well with vague inputs thus doesn’t not require any exact numerical model and can handle nonlinearity. This technique provides a framework for the extension to handle multiple special cases for optimized working of the system.

Keywords: photovoltaic, power, fuzzy logic, distributed generators, state of charge, load shedding, membership functions

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Authors: Daniel Llanes, Alfredo Reyes, Sonia E. Ruiz, Federico Valenzuela Beltran

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Steel frames have been used in building construction for more than one hundred years. Beam-column may be connected to columns using either stiffened or unstiffened angles at the top and bottom beam flanges. Designers often assume that these assemblies acted as “pinned” connections for gravity loads and that the stiffened connections would act as “fixed” connections for lateral loads. Observation of damages sustained by buildings during the 1994 Northridge earthquake indicated that, contrary to the intended behavior, in many cases, brittle fractures initiated within the connections at very low levels of plastic demand, and in some cases, while the structures remained essentially elastic. Due to the damage presented in these buildings other type of alternative connections have been proposed. According to a research funded by the Federal Emergency Management Agency (FEMA), the screwed connections have better performance when they are subjected to cyclic loads, but at the same time, these connections have some degree of flexibility. Due to this situation, some researchers ventured into the study of semi-rigid connections. In the present study three steel buildings, constituted by regular frames are analyzed. Two types of connections are considered: pinned and semi-rigid connections. With the aim to estimate their structural capacity, a number of incremental dynamic analyzes are performed. 3D structural models are used for the analyses. The seismic ground motions were recorded on sites near Los Angeles, California, where the structures are supposed to be located. The vulnerability curves of the building are obtained in terms of maximum inter-story drifts. The vulnerability curves (which correspond to the models with two different types of connections) are compared, and its implications on its structural design and performance is discussed.

Keywords: steel frame Buildings, vulnerability curves, semi-rigid connections, pinned connections

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Authors: Yue Huang, Hongcheng Gan

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The new urbanization pattern has led to a rapid growth in demand for short-distance intercity travel, and the emergence of new travel modes has also increased the variety of intercity travel options. In previous studies on intercity travel mode choice behavior, the impact of functional amenities of travel mode and travelers’ long-term personality characteristics has rarely been considered, and empirical results have typically been calibrated using revealed preference (RP) or stated preference (SP) data. This study designed a questionnaire that combines the RP and SP experiment from the perspective of a trip chain combining inner-city and intercity mobility, with consideration for the actual condition of the Huainan-Hefei traffic corridor. On the basis of RP/SP fusion data, a hybrid choice model considering both random taste heterogeneity and psychological characteristics was established to investigate travelers’ mode choice behavior for traditional train, high-speed rail, intercity bus, private car, and intercity online car-hailing. The findings show that intercity time and cost exert the greatest influence on mode choice, with significant heterogeneity across the population. Although inner-city cost does not demonstrate a significant influence, inner-city time plays an important role. Service attributes of travel mode, such as catering and hygiene services, as well as free wireless network supply, only play a minor role in mode selection. Finally, our study demonstrates that safety-seeking tendency, hedonism, and introversion all have differential and significant effects on intercity travel mode choice.

Keywords: intercity travel mode choice, stated preference survey, hybrid choice model, RP/SP fusion data, psychological latent variable, heterogeneity

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Authors: Innocent Uzougbo Onwuegbuzie

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Wireless Sensor Networks (WSNs) are crucial for numerous applications, yet they face significant challenges due to resource constraints such as limited power and memory. Traditional routing algorithms like Dijkstra, Ad hoc On-Demand Distance Vector (AODV), and Bellman-Ford, while effective in path establishment and discovery, are not optimized for the unique demands of WSNs due to their large memory footprint and power consumption. This paper introduces the Adaptive Energy-Aware Routing (AEAR) model, a solution designed to address these limitations. AEAR integrates reactive route discovery, localized decision-making using geographic information, energy-aware metrics, and dynamic adaptation to provide a robust and efficient routing strategy. We present a detailed comparative analysis using a dataset of 50 sensor nodes, evaluating power consumption, memory footprint, and path cost across AEAR, Dijkstra, AODV, and Bellman-Ford algorithms. Our results demonstrate that AEAR significantly reduces power consumption and memory usage while optimizing path weight. This improvement is achieved through adaptive mechanisms that balance energy efficiency and link quality, ensuring prolonged network lifespan and reliable communication. The AEAR model's superior performance underlines its potential as a viable routing solution for energy-constrained WSN environments, paving the way for more sustainable and resilient sensor network deployments.

Keywords: wireless sensor networks (WSNs), adaptive energy-aware routing (AEAR), routing algorithms, energy, efficiency, network lifespan

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Authors: Xvelian Qin

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Urban "organic renewal" based on the development of existing resources in high-density urban areas has become the mainstream of urban development in the new era. As an important stock resource of public space in high-density urban areas, promoting its value remodeling is an effective way to alleviate the shortage of public space resources. However, due to the lack of evaluation links in the process of underpass space renewal, a large number of underpass space resources have been left idle, facing the problems of low space conversion efficiency, lack of accuracy in development decision-making, and low adaptability of functional positioning to citizens' needs. Therefore, it is of great practical significance to construct the evaluation system of under-bridge space renewal potential and explore the renewal mode. In this paper, some of the under-bridge spaces in the main urban area of Chongqing are selected as the research object. Through the questionnaire interviews with the users of the built excellent space under the bridge, three types of six levels and twenty-two potential evaluation indexes of "objective demand factor, construction feasibility factor and construction suitability factor" are selected, including six levels of land resources, infrastructure, accessibility, safety, space quality and ecological environment. The analytical hierarchy process and expert scoring method are used to determine the index weight, construct the potential evaluation system of the space under the bridge in high-density urban areas of Chongqing, and explore the direction of renewal and utilization of its suitability. To provide feasible theoretical basis and scientific decision support for the use of under bridge space in the future.

Keywords: high density urban area, potential evaluation, space under bridge, updated using

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Authors: Sylvain Caillol, Maxence Fache, Bernard Boutevin

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Recent years have witnessed an increasing demand on renewable resource-derived polymers owing to increasing environmental concern and restricted availability of petrochemical resources. Thus, a great deal of attention was paid to renewable resources-derived polymers and to thermosetting materials especially, since they are crosslinked polymers and thus cannot be recycled. Also, most of thermosetting materials contain aromatic monomers, able to confer high mechanical and thermal properties to the network. Therefore, the access to biobased, non-harmful, and available aromatic monomers is one of the main challenges of the years to come. Starting from phenols available in large volumes from renewable resources, our team designed platforms of chemicals usable for the synthesis of various polymers. One of these phenols, vanillin, which is readily available from lignin, was more specifically studied. Various aromatic building blocks bearing polymerizable functions were synthesized: epoxy, amine, acid, carbonate, alcohol etc. These vanillin-based monomers can potentially lead to numerous polymers. The example of epoxy thermosets was taken, as there is also the problematic of bisphenol A substitution for these polymers. Materials were prepared from the biobased epoxy monomers obtained from vanillin. Their thermo-mechanical properties were investigated and the effect of the monomer structure was discussed. The properties of the materials prepared were found to be comparable to the current industrial reference, indicating a potential replacement of petrosourced, bisphenol A-based epoxy thermosets by biosourced, vanillin-based ones. The tunability of the final properties was achieved through the choice of monomer and through a well-controlled oligomerization reaction of these monomers. This follows the same strategy than the one currently used in industry, which supports the potential of these vanillin-derived epoxy thermosets as substitutes of their petro-based counterparts.

Keywords: lignin, vanillin, epoxy, amine, carbonate

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Authors: Pia Moschall, Kathrin Sackmann

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Considering a purchasing volume of around two trillion Euros per year, which equals about 14% of the European Union’s gross domestic product, European public authorities have significant market power. Making use of this market power by prioritizing the procurement of green products and services offers a great potential to contribute to the Green New Deal. The market demand that is created by Green Public Procurement (GPP) sets incentives for European producers to design and develop Green Products and Eco-Innovations. However, most procurement still does not consider environmental criteria. The goal of the work is to encourage the adaptation of GPP in the European Union. To this end, the drivers for the adaptation were investigated over different case studies. The paper analyzes good-practice cases from European authorities from 2010 to 2020 that were provided by the European Commission. This analysis was guided by Philipp Mayring’s method of qualitative content analysis, whereby the inductively formed categories led to the identification of nine major drivers. The most important ones are ‘use of official guidelines and standards, ‘political support and requirements as well as ‘market research and involvement.’ Further, the paper discusses mutual dependencies between several drivers and how to exploit them. A supporting infrastructure was identified as a crucial factor for the successful adaption of green public procurement. In the next step, the work aims to examine on which administrative level the single drivers can be implemented most effectively. Practical implications of this research are recommendations on how to create a supporting structure on a municipal, federal and national level, including training for the responsible staff, support tools, as well as guidelines and standards for involved stakeholders.

Keywords: content analysis, green public procurement, public authorities, sustainable procurement

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Authors: Armand Okende, Joëlle De Weerdt, Esther Fichtler, Maaike De Ridder, Hans Beeckman

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The rainforest plays a crucial role in regulating the climate balance. The biodiversity of tropical rainforests is undeniable, but many aspects remain poorly known, which directly influences its management. Despite the efforts of sustainable forest management, human pressure in terms of exploitation and smuggling of timber forms a problem compared to exploited species whose status is considered "vulnerable" on the IUCN red list compiled by. Commercial species in Class III of the Democratic Republic of Congo are the least known in the market operating, and their biology is unknown or non-existent. Identification of wood in terms of descriptions and anatomical measurements of the wood is in great demand for various stakeholders such as scientists, customs, IUCN, etc. The objective of this study is the qualitative and quantitative description of the anatomical characteristics of commercial species in Class III of DR Congo. The site of the Luki Biosphere Reserve was chosen because of its high tree species richness. This study focuses on the wood anatomy of 14 commercial species of Class III of DR Congo. Thirty-four wooden discs were collected for these species. The following parameters were measured in the field: Diameter at breast height (DBH), total height and geographic coordinates. Microtomy, identification of vessel parameters (diameter, density and grouping) and photograph of the microscopic sections and determining age were performed in this study. The results obtained are detailed anatomical descriptions of species in Class III of the Democratic Republic of Congo.

Keywords: sustainable management of forest, rainforest, commercial species of class iii, vessel diameter, vessel density, grouping vessel

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Authors: Patel Parul, Harsh Ganvit

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The construction industry is the second highest industry after agriculture provides employment in India. In developing countries like India, many construction projects are coming up to meet the demand. On the one hand, construction projects are increasing; on the other hand still, construction companies are struggling with many problems. One of the major problems is to ensure safe working conditions at the construction site. Due to a lack of safety awareness and ignorance of safety aspects, many fatal accidents are very common at the construction site in India. One of the key success factors for construction projects is “Accident-Free Construction Projects”. The construction projects can be divided into various categories like Infrastructure projects, industrial construction and real estate construction. Real estate projects are mainly comprised of commercial and residential projects. In the construction industry, private sectors play a huge role in urban and rural development and also contribute significantly to the growth of the nation. Infrastructure and Industrial projects are mainly executed by well-qualified construction contractors. For such projects, ensuring safety at construction projects is inevitable and probably one of the major clauses of contract documents as well. These projects are monitored from time to time by national agencies and researchers, too. However, Real estate projects are rarely monitored for safety aspects. No systematic contract system is followed for these projects. Safety is the most neglected aspect of these projects. In the current research projects, an attempt is made to carry out safety auditing for about 75 real estate projects. The objective of this work is to collect the activity-based safety survey of real estate projects in western India. The analysis of activity-based safety implementation for real estate projects is discussed in the present work. The activities are divided into three categories based on the data collected. The findings of this work will help local monitoring authorities to implement a safety management plan for real estate projects.

Keywords: construction safety, safety assessment, activity-based safety, real estate projects

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Authors: Suprehatin Suprehatin

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Improving the participation of smallholder farmers in horticultural value chains to benefit from the rapidly growing demand for high-value agricultural products is one strategy for raising farm income. However, smallholder farmer participation in Indonesian horticultural value chains is under-researched. To address this knowledge gap, this study aims to describe the current status of horticultural crop adoption in Indonesia and analyze the motivations and dynamics of smallholder farmer participation in horticultural value chains: why some small farmers join these new and potentially profitable chains and continue their participation. This study also examines the characteristics of farmers who adopted and those who did not adopt a new horticultural crop with respect to the household (farmer), farm and institutional characteristics. The analysis was conducted using unique data from a 2013 survey of 960 Indonesian farmers on Java Island that produce a variety of agricultural products. Basic statistical analysis showed relatively low adoption rates (10%) of new horticultural crops amongst 960 selected Indonesian farmers with different decisions made in terms of number and timing of new horticultural crop adoption. Adopters were motivated mainly by higher profit, higher yield, and more cash opportunities. The result also showed that current low rates of horticultural crop adoption are associated with a variety of factors, such as lower levels of education among farmers, resource constraints, lack of information on horticultural crop production and low participation in farmer groups. These findings will be helpful for policymakers when designing policies and programs to promote greater participation of Indonesian smallholder farmers in horticultural value chains. In other words, a revitalisation of agricultural policy beyond staple food is important to seize potential benefits from the ongoing agricultural food market transformation.

Keywords: farmer adoption, high value, horticultural crops, Indonesia

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Authors: Joseph Mary Ssembatya, Blessing Michael Taremwa

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Background: Multiple schwannomas are typically associated with neurofibromatosis type 1 (NF1), but rare cases occur independently of neurofibromatosis. Schwannomas are benign, slow-growing tumors, primarily affecting the cervical and lumbar spine. When large, they may extend over multiple vertebral levels, posing surgical challenges. Case Presentation: A 13-year-old Ugandan Munyankore female patient, presented with a 6-year history of progressive quadriparesis, particularly in the lower limbs. Clinical examination showed hypertonia and hyperreflexia, with no indicators of neurofibromatosis or prior trauma. MRI revealed two “kissing” schwannomas extending from C2 to T2 in the cervical spine. Decompressive surgery was performed through laminoplasty and partial lesion resection, and histology confirmed schwannoma. Two weeks postoperatively, the patient experienced cerebrospinal fluid (CSF) leakage, neck pain, and headache, which required re-operation and duraplasty. Following these interventions, the patient’s neurological status stabilized, with noted improvement in lower limb strength. Discussion: “Kissing” schwannomas are most frequently documented in the cerebellopontine angle, rarely in the spine, and even more rarely in children. While multiple schwannomas are often associated with NF2, this case had no family history or clinical signs of the disorder. Giant invasive spinal schwannomas (GISS) that span multiple vertebrae demand intricate surgical approaches due to their proximity to neurovascular structures. Conclusion: This is the first reported case of kissing cervical schwannomas in a young patient from a low- to middle-income country. Surgical decompression, though challenging, is critical for neurological recovery in such advanced cases.

Keywords: kissing schwannoma, cervical spine, low resource, young, uganda

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Authors: Alaa Alateeqi, Sara Aldhulaiee, Sara Alibraheem, Noura Alsaleh

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For the past few decades or so, Kuwait's local food industry has grown remarkably due to increase in demand for processed or semi processed food products in the market. It is important that the ever increasing food manufacturing/processing units maintain the required quality standards as per regional and to some extent international quality requirements. It has been realized that all Kuwait food manufacturing units should understand and follow the international standard practices, and moreover a set of guidelines must be set for quality assurance such that any new business in this area is aware of the minimum requirements. The current study has been undertaken to identify the gaps in Kuwait food industries in following the Good Manufacturing Practices (GMP) in terms of quality planning, control and quality assurance. GMP refers to Good Manufacturing Practices, which are a set of rules, laws or regulations that certify producing products within quality standards and ensuring that it is safe, pure and effective. The present study therefore reports about a ‘case study’ in a reputed food manufacturing unit in Kuwait; starting from assessment of the current practices followed by diagnosis, report of the diagnosis and road map and corrective measures for GMP implementation in the unit. The case study has also been able to identify the best practices and establish a benchmarking data for other companies to follow, through measuring the selected company's quality, policies, products and strategies and compare it with the established benchmarking data. A set of questionnaires and assessment mechanism has been established for companies to identify their ‘benchmarking score’ in relation to the number of non-conformities and conformities with the GMP standard requirements.

Keywords: good manufacturing practices, GMP, benchmarking, Kuwait Food Industries, food quality

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Authors: Luís Marques, João Rocha, Andreia Fernandes, Maria Moura, Cláudia Caseiro, Filipa Figueiredo, João Nunes

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The implementation of circularity strategies other than recycling, such as reducing the amount of raw material, as well as reusing or sharing existing products, remains marginal. The European Commission announced that the transition towards a more circular economy could lead to the net creation of about 700,000 jobs in Europe by 2030, through additional labour demand from recycling plants, repair services and other circular activities. Efforts to create new circular business models in accordance with completely circular processes, as opposed to linear ones, have increased considerably in recent years. In order to create a societal Circular Economy transition model, it is necessary to include innovative solutions, where startups play a key role. Early-stage startups based on new business models according to circular processes often face difficulties in creating enough impact. The StartUp Zero Program designs a model and approach to increase the flow of startups in the Circular Economy field, focusing on a systemic decision analysis and multi-generational approach, considering Multi-Criteria Decision Analysis to support a decision-making tool, which is also supported by the use of a combination of an Analytical Hierarchy Process and Multi-Attribute Value Theory methods. We define principles, criteria and indicators for evaluating startup prerogatives, quantifying the evaluation process in a unique result. Additionally, this entrepreneurship program spanning 16 months involved more than 2400 young people, from ages 14 to 23, in more than 200 interaction activities.

Keywords: circular economy, entrepreneurship, startups;, multi-criteria decision analysis

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Authors: Harsi Nastiti, Haidar Fikri

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Indonesia has been known for its diversity of cultures, ethnics, religions, and races. This diversity signs as the uniqueness of the country, so tolerance becomes vital point here. As a unitary state, tolerance value is established strongly as the foundation of democracy implementation but recently this tolerance condition facing up some problems after regional election. In this case, religion issue takes a main role for the Indonesian political system which is managed into tolerance breaker especially for local democracy. The election of Jakarta’s Governor 2017 can be said as the momentum for the people to rethink the democracy and tolerance meaning. It begins from one of the governor candidates who makes statement about the majority religion and unfortunately the candidate comes from the minority. The statement emerges into a new social movement based on religiosity. Basically, the social movement which is coordinated by Islamic Defender Front (Front Pembela Islam or FPI) and National Movement to Safeguard the Fatwa-Indonesian Ulama Council (GNPF-MUI) want to demand the justice in the name of blasphemy. The action continuously happens in different names (Action 411, 212, etc.). So, this article analyzes the new phenomenon and how does the impact for the tolerance and democracy life in Indonesia. The method is using qualitative method by review of literature and media content analysis. Results show this phenomenon potentially spreading new conflicts far beyond the goal of the action itself; justice. It makes the conflicts more complex after there are actions such as; Parade Kebhinekaan and Aksi Lilin which contrary reacts to the actions before. These actions and reactions rise up the sensitive issues for Indonesia like religions, Pancasila, unity in diversity, ethnics, and races. At the same time raising skepticism; will it be over after the candidate is getting sentenced or becomes the dangerous latent conflict that will threaten tolerance and democracy in Indonesia.

Keywords: conflict, democracy, religion, tolerance

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Authors: Lotha Valan, Åsa Hörnsten, Ulf Isaksson

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Introduction: Sweden has a national child health care program (CHCP) where all parents are offered support to raise their children and support them for lifelong health. A systematic review concludes that there is a request for guidance in using the internet effectively for the health purposes of their children. However, a study about internet use among young mothers means that the internet is not always easy to navigate for parents, and they may need support. To fill this gap and develop a digital channel to complement the child health care (CHC) for the support of parents of children within CHC, there is a demand to investigate parents' needs in relation to this purpose. Methods: The study had a qualitative approach using focus group interviews with parents. The interview data were analyzed using qualitative content analysis. Results: The main theme highlights that parents expected that a digital support channel would be something that might strengthen them toward independence concerning the care of their children in a positive way. However, they also felt that they needed personal support and that relationships with other parents and the child health care nurse were significant and meaningful. Another parental desire that emerged was that a future digital channel would facilitate and simplify access to care, and they suggested having both planned and urgent times available for parents to book. The digital channel was expected to make this possible and be a good complement to the physical contacts the traditional child healthcare currently offers. Discussion/conclusions: The parents in this study believed that digital solutions could increase their parental power in relation to the care of their children. Examples were given as nurse-led parent groups where parents with similar problems and experiences around their children could support each other and were expected to strengthen them over time. The parents stressed that a planned digital support channel also needs satisfactory solutions for both contact and response. It was suggested that there should be bookable times for both planned and urgent needs and also the possibility of rescheduling visits.

Keywords: child healthcare, parents, digital support, nursing

Procedia PDF Downloads 77