Search results for: laboratory and field conditions

Authors: Chia-Jung Chang, Sheng-Che Chen, Ming-Long Yeh, Chih-Wei Wang, Chih-Han Chang

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Introduction and Motivation: In recent years, magnesium alloy is used to be a kind of medical biodegradable materials. Magnesium is an essential element in the body and is efficiently excreted by the kidneys. Furthermore, the mechanical properties of magnesium alloy is closest to human bone. However, in some cases magnesium alloy corrodes so quickly that it would release hydrogen on surface of implant. The other product is hydroxide ion, it can significantly increase the local pH value. The above situations may have adverse effects on local cell functions. On the other hand, nowadays magnesium alloy corrode too fast to maintain the function of implant until the healing of tissue. Therefore, much recent research about magnesium alloy has focused on controlling the corrosion rate. The in vitro corrosion behavior of magnesium alloys is affected by many factors, and pH value is one of factors. In this study, we will study on the influence of pH value on the corrosion behavior of magnesium alloy by the Micro-CT (micro computed tomography) and other instruments.Material and methods: In the first step, we make some guiding plates for specimens of magnesium alloy AZ91 by Rapid Prototyping. The guiding plates are able to be a standard for the degradation of specimen, so that we can use it to make sure the position of specimens in the CT image. We can also simplify the conditions of degradation by the guiding plates.In the next step, we prepare the solution with different pH value. And then we put the specimens into the solution to start the corrosion test. The CT image, surface photographs and weigh are measured on every twelve hours. Results: In the primary results of the test, we make sure that CT image can be a way to quantify the corrosion behavior of magnesium alloy. Moreover we can observe the phenomenon that corrosion always start from some erosion point. It’s possibly based on some defect like dislocations and the voids with high strain energy in the materials. We will deal with the raw data into Mass Loss (ML) and corrosion rate by CT image, surface photographs and weigh in the near future. Having a simple prediction, the pH value and degradation rate will be negatively correlated. And we want to find out the equation of the pH value and corrosion rate. We also have a simple test to simulate the change of the pH value in the local region. In this test the pH value will rise to 10 in a short time. Conclusion: As a biodegradable implant for the area with stagnating body fluid flow in the human body, magnesium alloy can cause the increase of local pH values and release the hydrogen. Those may damage the human cell. The purpose of this study is finding out the equation of the pH value and corrosion rate. After that we will try to find the ways to overcome the limitations of medical magnesium alloy.

Keywords: magnesium alloy, biodegradable materials, corrosion, micro-CT

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Authors: Douglas N. Simoes, Michele Pittol, Vanda F. Ribeiro, Daiane Tomacheski, Ruth M. C. Santana

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Thermoplastic elastomers (TPE) compounds are used in a wide range of applications, like home appliances, automotive components, medical devices, footwear, and others. These materials are susceptible to microbial attack, causing a crack in polymer chains compounds based on SEBS copolymers, poly (styrene-b-(ethylene-co-butylene)-b-styrene, are a class of TPE, largely used in domestic appliances like refrigerator seals (gaskets), bath mats and sink squeegee. Moisture present in some areas (such as shower area and sink) in addition to organic matter provides favorable conditions for microbial survival and proliferation, contributing to the spread of diseases besides the reduction of product life cycle due the biodegradation process. Zinc oxide (ZnO) has been studied as an alternative antibacterial additive due its biocidal effect. It is important to know the influence of these additives in the properties of the compounds, both at the beginning and during the life cycle. In that sense, the aim of this study was to evaluate the effect of accelerated aging in oven on antibacterial and mechanical properties of ZnO loaded SEBS based TPE compounds. Two different comercial zinc oxide, named as WR and Pe were used in proportion of 1%. A compound with no antimicrobial additive (standard) was also tested. The compounds were prepared using a co-rotating double screw extruder (L/D ratio of 40/1 and 16 mm screw diameter). The extrusion parameters were kept constant for all materials, screw rotation rate was set at 226 rpm, with a temperature profile from 150 to 190 ºC. Test specimens were prepared using the injection molding machine at 190 ºC. The Standard Test Method for Rubber Property—Effect of Liquids was applied in order to simulate the exposition of TPE samples to detergent ingredients during service. For this purpose, ZnO loaded TPE samples were immersed in a 3.0% w/v detergent (neutral) and accelerated aging in oven at 70°C for 7 days. Compounds were characterized by changes in mechanical (hardness and tension properties) and mass. The Japan Industrial Standard (JIS) Z 2801:2010 was applied to evaluate antibacterial properties against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The microbiological tests showed a reduction up to 42% in E. coli and up to 49% in S. aureus population in non-aged samples. There were observed variations in elongation and hardness values with the addition of zinc The changes in tensile at rupture and mass were not significant between non-aged and aged samples.

Keywords: antimicrobial, domestic appliance, sebs, zinc oxide

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Authors: Nadeem Yousuf Khan

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This paper proposes the formation of a digital emergency response system (dERS) in the aged, long-term care, and chronic disease setups in the post-COVID healthcare ecosystem, focusing on the Asia Pacific market where the aging population is increasing significantly. It focuses on the use of digital technologies such as wearables, a global positioning system (GPS), and mobile applications to build an integrated care system for old folks with co-morbidities and other chronic diseases. The paper presents a conceptual framework of a connected digital health ecosystem that not only provides proactive care to registered patients but also prevents the damages due to sudden conditions such as strokes by alerting and treating the patients in a digitally connected and coordinated manner. A detailed review of existing digital health technologies such as wearables, GPS, and mobile apps was conducted in context with the new post-COVID healthcare paradigm, along with a detailed literature review on the digital health policies and usability. A good amount of research papers is available in the application of digital health, but very few of them discuss the formation of a new framework for a connected digital ecosystem for the aged care population, which is increasing around the globe. A connected digital emergency response system has been proposed by the author whereby all registered patients (chronic disease and aged/long term care) will be connected to the proposed digital emergency response system (dERS). In the proposed ecosystem, patients will be provided with a tracking wrist band and a mobile app through which the control room will be monitoring the mobility and vitals such as atrial fibrillation (AF), blood sugar, blood pressure, and other vital signs. In addition to that, an alert in case if the patient falls down will add value to this system. In case of any variation in the vitals, an alert is sent to the dERS 24/7, and dERS clinical staff immediately trigger that alert which goes to the connected hospital and the adulatory service providers, and the patient is escorted to the nearest connected tertiary care hospital. By the time, the patient reaches the hospital, dERS team is ready to take appropriate clinical action to save the life of the patient. Strokes or myocardial infarction patients can be prevented from disaster if they are accessible to engagement healthcare. This dERS will play an effective role in saving the lives of aged patients or patients with chronic co-morbidities.

Keywords: aged care, atrial fibrillation, digital health, digital emergency response system, digital technology

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Authors: Anda-veronica Gherman, Dimitrios Varthalitis

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Neurosurgery, like many surgical specialties, undoubtedly exhibits a significant gender gap, particularly in leadership positions. While increasing women representation in neurosurgery is important, it is crucial to increase their presence in leadership positions. Across the globe and Europe there are concerning trends of only 4% of all neurosurgical departments being chaired by women. This study aims to explore the situation regarding gender disparities in leadership in the United Kingdom and to identify possible contributing factors as well as discussing future strategies to bridge this gap. Methods: A literature review was conducted utilising PubMed as main database with search keywords including ‘female neurosurgeon’, ‘women neurosurgeon’, ‘gender disparity’, ‘leadership’ and ‘UK’. Additionally, a manual search of all neurosurgical departments in the UK was performed to identify the current female department leads and training director leads. Results: The literature search identified a paucity of literature addressing specifically leadership in female neurosurgeons within the UK, with very few published papers specifically on this topic. Despite more than half of medical students in the UK being female, only a small proportion pursue a surgical career, with neurosurgery being one of the least represented specialties. Only 27% of trainee neurosurgeons are female, and numbers are even lower at a consultant level, where women represent just 8%.Findings from published studies indicated that only 6.6% of leadership positions in neurosurgery are occupied by women in the UK. Furthermore, our manual searches across UK neurosurgical departments revealed that around 5% of department lead positions are currently held by women. While this figure is slightly higher than the European average of 4%, it remains lower compared to figures of 10% in other North-West European countries. The situation is slightly more positive looking at the training directors, with 15% being female. Discussion: The findings of this study highlight a significant gender disparity in leadership positions within neurosurgery in the UK, which may have important implications, perpetuating the lack of diversity on the decision-making process, limiting the career advancement opportunities of women and depriving the neurosurgical field from the voices, opinions and talents of women. With women representing half of the population, there is an undeniable need for more female leaders at the policy-making level. There are many barriers that can contribute to these numbers, including bias, stereotypes, lack of mentorship and work-like balance. A few solutions to overcome these barriers can be training programs addressing bias and impostor syndrome, leadership workshops tailored for female needs, better workplace policies, increased in formal mentorship and increasing the visibility of women in neurosurgery leadership positions through media, speaking opportunities, conferences, awards etc. And lastly, more research efforts should focus on the leadership and mentorship of women in neurosurgery, with an increased number of published papers discussing these issues.

Keywords: female neurosurgeons, female leadership, female mentorship, gender disparities

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Authors: Andreas Hirseland, Lukas Kerschbaumer

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In Germany, during the past years there constantly are about one million long term unemployed who did not benefit from the prospering labor market while most short term unemployed did. Instead, they are continuously dependent on welfare and sometimes precarious short-term employment, experiencing work poverty. Long term unemployment thus turns into a main obstacle to regular employment, especially if accompanied by other impediments such as low level education (school/vocational), poor health (especially chronical illness), advanced age (older than fifty), immigrant status, motherhood or engagement in care for other relatives. Almost two thirds of all welfare recipients have multiple impediments which hinder a successful transition from welfare back to sustainable and sufficient employment. Hiring them is often considered as an investment too risky for employers. Therefore formal application schemes based on formal qualification certificates and vocational biographies might reduce employers’ risks but at the same time are not helpful for long-term unemployed and welfare recipients. The panel survey ‘Labor market and social security’ (PASS; ~15,000 respondents in ~10,000 households), carried out by the Institute of Employment Research (the research institute of the German Federal Labor Agency), shows that their chance to get back to work tends to fall to nil. Only 66 cases of such unlikely transitions could be observed. In a sequential explanatory mixed-method study, the very scarce ‘success stories’ of unlikely transitions from long term unemployment to work were explored by qualitative inquiry – in-depth interviews with a focus on biography accompanied by qualitative network techniques in order to get a more detailed insight of relevant actors involved in the processes which promote the transition from being a welfare recipient to work. There is strong evidence that sustainable transitions are influenced by biographical resources like habits of network use, a set of informal skills and particularly a resilient way of dealing with obstacles, combined with contextual factors rather than by job-placement procedures promoted by Job-Centers according to activation rules or by following formal paths of application. On the employer’s side small and medium-sized enterprises are often found to give job opportunities to a wider variety of applicants, often based on a slow but steadily increasing relationship leading to employment. According to these results it is possible to show and discuss some limitations of (German) activation policies targeting welfare dependency and long-term unemployment. Based on these findings, indications for more supportive small scale measures in the field of labor-market policies are suggested to help long-term unemployed with multiple impediments to overcome their situation.

Keywords: against-all-odds, economic sociology, long-term unemployment, mixed-methods

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Authors: Xiaoqian Zhang, Ping Zou, Pengcheng Li

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Salt stress is one of the most serious abiotic stresses, and it can lead to the reduction of agricultural productivity. High salt concentration makes it more difficult for roots to absorb water and disturbs the homeostasis of cellular ions resulting in osmotic stress, ion toxicity and generation of reactive oxygen species (ROS). Compared with the normal physiological conditions, salt stress could inhibit the photosynthesis, break metabolic balance and damage cellular structures, and ultimately results in the reduction of crop yield. Therefore it is vital to develop practical methods for improving the salt tolerance of plants. Chitooligomers (COS) is partially depolymerized products of chitosan, which is consisted of D-glucosamine and N-acetyl-D-glucosamine. In agriculture, COS has the ability to promote plant growth and induce plant innate immunity. The bioactivity of COS closely related to its degree of polymerization (DP) and acetylation (DA). However, most of the previous reports fail to mention the function of COS with different DP and DAs in improving the capacity of plants against salt stress. Accordingly, in this study, chitooligomers (COS) with different degrees of DAs were used to test wheat seedlings response to salt stress. In addition, the determined degrees of polymerization (DPs) COS(DP 4-12) and a heterogeneous COS mixture were applied to explore the relationship between the DP of COSs and its effect on the growth of wheat seedlings in response to salt stress. It showed that COSs, the exogenous elicitor, could promote the growth of wheat seedling, reduce the malondialdehyde (MDA) concentration, and increase the activities of antioxidant enzymes. The results of mRNA expression level test for salt stress-responsive genes indicated that COS keep plants away from being hurt by the salt stress via the regulation of the concentration and the increased antioxidant enzymes activities. Moreover, it was found that the activities of COS was closely related to its Das and COS (DA: 50%) displayed the best salt resistance activity to wheat seedlings. The results also showed that COS with different DP could promote the growth of wheat seedlings under salt stress. COS with a DP (6-8) showed better activities than the other tested samples, implied its activity had a close relationship with its DP. After treatment with chitohexaose, chitoheptaose, and chitooctaose, the photosynthetic parameters were improved obviously. The soluble sugar and proline contents were improved by 26.7%-53.3% and 43.6.0%-70.2%, respectively, while the concentration of malondialdehyde (MDA) was reduced by 36.8% - 49.6%. In addition, the antioxidant enzymes activities were clearly activated. At the molecular level, the results revealed that they could obviously induce the expression of Na+/H+ antiporter genes. In general, these results were fundamental to the study of action mechanism of COS on promoting plant growth under salt stress and the preparation of plant growth regulator.

Keywords: chitooligomers (COS), degree of polymerization (DP), degree of acetylation (DA), salt stress

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Authors: Sarah Alamolhoda, Kevin J. Smith, Xiaotao Bi, Naoko Ellis

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For millennials, biomass has been the most important source of fuel used to produce energy. Energy derived from biomass is renewable by re-growth of biomass. Various technologies are used to convert biomass to potential renewable products including combustion, gasification, pyrolysis and fermentation. Gasification is the incomplete combustion of biomass in a controlled environment that results in valuable products such as syngas, biooil and biochar. Syngas is a combustible gas consisting of hydrogen (H₂), carbon monoxide (CO), carbon dioxide (CO₂), and traces of methane (CH₄) and nitrogen (N₂). Cleaned syngas can be used as a turbine fuel to generate electricity, raw material for hydrogen and synthetic natural gas production, or as the anode gas of solid oxide fuel cells. In this work, syngas as a product of woody biomass gasification in British Columbia, Canada, was introduced to two consecutive fixed bed reactors to perform a catalytic water gas shift reaction followed by a catalytic methanation reaction. The water gas shift reaction is a well-established industrial process and used to increase the hydrogen content of the syngas before the methanation process. Catalysts were used in the process since both reactions are reversible exothermic, and thermodynamically preferred at lower temperatures while kinetically favored at elevated temperatures. The water gas shift reactor and the methanation reactor were packed with Cu-based catalyst and Ni-based catalyst, respectively. Simulated syngas with different percentages of CO, H₂, CH₄, and CO₂ were fed to the reactors to investigate the effect of operating conditions in the unit. The water gas shift reaction experiments were done in the temperature of 150 ˚C to 200 ˚C, and the pressure of 550 kPa to 830 kPa. Similarly, methanation experiments were run in the temperature of 300 ˚C to 400 ˚C, and the pressure of 2340 kPa to 3450 kPa. The Methanation reaction reached 98% of CO conversion at 340 ˚C and 3450 kPa, in which more than half of CO was converted to CH₄. Increasing the reaction temperature caused reduction in the CO conversion and increase in the CH₄ selectivity. The process was designed to be renewable and release low greenhouse gas emissions. Syngas is a clean burning fuel, however by going through water gas shift reaction, toxic CO was removed, and hydrogen as a green fuel was produced. Moreover, in the methanation process, the syngas energy was transformed to a fuel with higher energy density (per volume) leading to reduction in the amount of required fuel that flows through the equipment and improvement in the process efficiency. Natural gas is about 3.5 times more efficient (energy/ volume) than hydrogen and easier to store and transport. When modification of existing infrastructure is not practical, the partial conversion of renewable hydrogen to natural gas (with up to 15% hydrogen content), the efficiency would be preserved while greenhouse gas emission footprint is eliminated.

Keywords: renewable natural gas, methane, hydrogen, gasification, syngas, catalysis, fuel

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Authors: Federica Marangio

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This study looks at the triangle of knowledge: research-education-innovation as growth engine of an inclusive and sustainable society, where the research is the strategic process which allows the acquisition of knowledge, innovation appraises the knowledge acquired and the education is the enabling factor of the human capital to create entrepreneurial capital. Where does Italy and China stand in the global geography of innovation? Europe is calling on a smart, inclusive and sustainable growth through a specializing process that looks at the social and economic challenges, able to understand the characteristics of specific geographic areas. It is easily questionable why it is not as simple as it looks to come up with entrepreneurial ideas in all the geographic areas. Seen that the technology plus the human capital should be the means through which is possible to innovate and contribute to the boost of innovation culture, then the young educated people can be seen as the society changing agents and it becomes clear the importance of investigating the skills and competencies that lead to innovation. By starting innovation-based activities, other countries on an international level, are able now to be part of an healthy innovative ecosystem which is the result of a strong growth policy which enables innovation. Analyzing the geography of the innovation on a global scale, comes to light that the innovative entrepreneurship is the process which portrays the competitiveness of the regions in the knowledge-based economy as strategic process able to match intellectual capital and market opportunities. The level of innovative entrepreneurship is not only the result of the endogenous growth ability of the enterprises, but also by significant relations with other enterprises, universities, other centers of education and institutions. To obtain more innovative entrepreneurship is necessary to stimulate more synergy between all these territory actors in order to create, access and value existing and new knowledge ready to be disseminate. This study focuses on individual’s lived experience and the researcher believed that she can’t understand the human actions without understanding the meaning that they attribute to their thoughts, feelings, beliefs and so given she needed to understand the deeper perspectives captured through face-to face interaction. A case study approach will contribute to the betterment of knowledge in this field. This case study will represent a picture of the innovative ecosystem and the entrepreneurial mindset as a key ingredient of endogenous growth and a must for sustainable local and regional development and social cohesion. The case study will be realized analyzing two Chinese companies. A structured set of questions will be asked in order to gain details on what generated success or failure in the different situations with the past and at the moment of the research. Everything will be recorded not to lose important information during the transcription phase. While this work is not geared toward testing a priori hypotheses, it is nevertheless useful to examine whether the projects undertaken by the companies, were stimulated by enabling factors that, as result, enhanced or hampered the local innovation culture.

Keywords: Entrepreneurship, education, geography of innovation, education.

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Authors: Mohammad Lemar Zalmai, Osman Hurol Turkakin, Cemil Akcay, Ekrem Manisali

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In public construction projects, determining the contract period in the award phase is one of the most important factors. The contract period establishes the baseline for creating the cash flow curve and progress payment planning in the post-award phase. If overestimated, project duration causes losses for both the owner and the contractor. Therefore, it is essential to base construction project duration on reliable forecasting. In Turkey, schedules are usually built using the bar chart (Gantt) schedule, especially for governmental construction agencies. The usage of these schedules is limited for bidding purposes. Although the bar-chart schedule is useful in some cases, it lacks logical connections between activities; it would be harder to obtain the activities that have more effects than others on the project's total duration, especially in large complex projects. In this study, a construction schedule is prepared with Critical Path Method (CPM) that addresses the above-mentioned discrepancies. CPM is a simple and effective method that displays project time and critical paths, showing results of forward and backward calculations with considering the logic relationships between activities; it is a powerful tool for planning and managing all kinds of construction projects and is a very convenient method for the construction industry. CPM provides a much more useful and precise approach than traditional bar-chart diagrams that form the basis of construction planning and control. CPM has two main application utilities in the construction field; the first one is obtaining project duration, which is called an as-planned schedule that includes as-planned activity durations with relationships between subsequent activities. Another utility is during the project execution; each activity is tracked, and their durations are recorded in order to obtain as-built schedule, which is named as a black box of the project. The latter is more useful for delay analysis, and conflict resolutions. These features of CPM have been popular around the world. However, it has not been yet extensively used in Turkey. In this study, a real construction project is investigated as a case study; CPM-based scheduling is used for establishing both of as-built and as-planned schedules. Problems that emerged during the construction phase are identified and categorized. Subsequently, solutions are suggested. Two scenarios were considered. In the first scenario, project progress was monitored based as CPM was used to track and manage progress; this was carried out based on real-time data. In the second scenario, project progress was supposedly tracked based on the assumption that the Gantt chart was used. The S-curves of the two scenarios are plotted and interpreted. Comparing the results, possible faults of the latter scenario are highlighted, and solutions are suggested. The importance of CPM implementation has been emphasized and it has been proposed to make it mandatory for preparation of construction schedule based on CPM for public construction projects contracts.

Keywords: as-built, case-study, critical path method, Turkish government sector projects

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Authors: Johannes Günther

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Time Sensitive Networking (TSN), standardized in the IEEE 802.1 standard, has been lent increasing attention in the context of mission critical systems. Such mission critical systems, e.g., in the automotive domain, aviation, industrial, and smart factory domain, are responsible for coordinating complex functionalities in real time. In many of these contexts, a reliable data exchange fulfilling hard time constraints and quality of service (QoS) conditions is of critical importance. TSN standards are able to provide guarantees for deterministic communication behaviour, which is in contrast to common best-effort approaches. Therefore, the superior QoS guarantees of TSN may aid in the development of new technologies, which rely on low latencies and specific bandwidth demands being fulfilled. TSN extends existing Ethernet protocols with numerous standards, providing means for synchronization, management, and overall real-time focussed capabilities. These additional QoS guarantees, as well as management mechanisms, lead to an increased attack surface for potential malicious attackers. As TSN guarantees certain deadlines for priority traffic, an attacker may degrade the QoS by delaying a packet beyond its deadline or even execute a denial of service (DoS) attack if the delays lead to packets being dropped. However, thus far, security concerns have not played a major role in the design of such standards. Thus, while TSN does provide valuable additional characteristics to existing common Ethernet protocols, it leads to new attack vectors on networks and allows for a range of potential attacks. One answer to these security risks is to deploy defense mechanisms according to a moving target defense (MTD) strategy. The core idea relies on the reduction of the attackers' knowledge about the network. Typically, mission-critical systems suffer from an asymmetric disadvantage. DoS or QoS-degradation attacks may be preceded by long periods of reconnaissance, during which the attacker may learn about the network topology, its characteristics, traffic patterns, priorities, bandwidth demands, periodic characteristics on links and switches, and so on. Here, we implemented and tested several MTD-like defense strategies against different attacker models of varying capabilities and budgets, as well as collaborative attacks of multiple attackers within a network, all within the context of TSN networks. We modelled the networks and tested our defense strategies on an OMNET++ testbench, with networks of different sizes and topologies, ranging from a couple dozen hosts and switches to significantly larger set-ups.

Keywords: network security, time sensitive networking, moving target defense, cyber security

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Authors: Alak Kumar Patra, Nilanjan Mitra

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Higher strength to weight ratio is the main advantage of sandwich composite structures. Interfacial delamination between the face sheet and core is a major problem in these structures. Many research works are devoted to improve the interfacial fracture toughness of composites majorities of which are on nano and laminated composites. Work on influence of multiwalled carbon nano-tubes (MWCNT) dispersed resin system on interface fracture of glass-epoxy PVC core sandwich composite is extremely limited. Finite element study is followed by experimental investigation on interface fracture toughness of glass-epoxy (G/E) PVC core sandwich composite with and without MWCNT. Results demonstrate an improvement in interface fracture toughness values (Gc) of samples with a certain percentages of MWCNT. In addition, dispersion of MWCNT in epoxy resin through sonication followed by mixing of hardener and vacuum resin infusion (VRI) technology used in this study is an easy and cost effective methodology in comparison to previously adopted other methods limited to laminated composites. The study also identifies the optimum weight percentage of MWCNT addition in the resin system for maximum performance gain in interfacial fracture toughness. The results agree with finite element study, high-resolution transmission electron microscope (HRTEM) analysis and fracture micrograph of field emission scanning electron microscope (FESEM) investigation. Interface fracture toughness (GC) of the DCB sandwich samples is calculated using the compliance calibration (CC) method considering the modification due to shear. Compliance (C) vs. crack length (a) data of modified sandwich DCB specimen is fitted to a power function of crack length. The calculated mean value of the exponent n from the plots of experimental results is 2.22 and is different from the value (n=3) prescribed in ASTM D5528-01for mode 1 fracture toughness of laminate composites (which is the basis for modified compliance calibration method). Differentiating C with respect to crack length (a) and substituting it in the expression GC provides its value. The research demonstrates improvement of 14.4% in peak load carrying capacity and 34.34% in interface fracture toughness GC for samples with 1.5 wt% MWCNT (weight % being taken with respect to weight of resin) in comparison to samples without MWCNT. The paper focuses on significant improvement in experimentally determined interface fracture toughness of sandwich samples with MWCNT over the samples without MWCNT using much simpler method of sonication. Good dispersion of MWCNT was observed in HRTEM with 1.5 wt% MWCNT addition in comparison to other percentages of MWCNT. FESEM studies have also demonstrated good dispersion and fiber bridging of MWCNT in resin system. Ductility is also observed to be higher for samples with MWCNT in comparison to samples without.

Keywords: carbon nanotube, epoxy resin, foam, glass fibers, interfacial fracture, sandwich composite

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Authors: Kitty Kioskli, Theofanis Fotis, Nineta Polemi

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The European Union (EU) directive Artificial Intelligence (AI) Act in Article 9 requires that risk management of AI systems includes both technical and human oversight, while according to NIST_AI_RFM (Appendix C) and ENISA AI Framework recommendations, claim that further research is needed to understand the current limitations of social threats and human-AI interaction. AI threats within social contexts significantly affect the security and trustworthiness of the AI systems; they are interrelated and trigger technical threats as well. For example, lack of explainability (e.g. the complexity of models can be challenging for stakeholders to grasp) leads to misunderstandings, biases, and erroneous decisions. Which in turn impact the privacy, security, accountability of the AI systems. Based on the NIST four fundamental criteria for explainability it can also classify the explainability threats into four (4) sub-categories: a) Lack of supporting evidence: AI systems must provide supporting evidence or reasons for all their outputs. b) Lack of Understandability: Explanations offered by systems should be comprehensible to individual users. c) Lack of Accuracy: The provided explanation should accurately represent the system's process of generating outputs. d) Out of scope: The system should only function within its designated conditions or when it possesses sufficient confidence in its outputs. Biases may also stem from historical data reflecting undesired behaviors. When present in the data, biases can permeate the models trained on them, thereby influencing the security and trustworthiness of the of AI systems. Social related AI threats are recognized by various initiatives (e.g., EU Ethics Guidelines for Trustworthy AI), standards (e.g. ISO/IEC TR 24368:2022 on AI ethical concerns, ISO/IEC AWI 42105 on guidance for human oversight of AI systems) and EU legislation (e.g. the General Data Protection Regulation 2016/679, the NIS 2 Directive 2022/2555, the Directive on the Resilience of Critical Entities 2022/2557, the EU AI Act, the Cyber Resilience Act). Measuring social threats, estimating the risks to AI systems associated to these threats and mitigating them is a research challenge. In this paper it will present the efforts of two European Commission Projects (FAITH and THEMIS) from the HorizonEurope programme that analyse the social threats by building cyber-social exercises in order to study human behaviour, traits, cognitive ability, personality, attitudes, interests, and other socio-technical profile characteristics. The research in these projects also include the development of measurements and scales (psychometrics) for human-related vulnerabilities that can be used in estimating more realistically the vulnerability severity, enhancing the CVSS4.0 measurement.

Keywords: social threats, artificial Intelligence, mitigation, social experiment

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Authors: Pamela Del Rosario, Elisabetta Palumbo, Marzia Traverso

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The building sector plays an important role in addressing pressing environmental issues such as climate change and resource scarcity. The energy performance of buildings is considerably affected by the external envelope. In fact, a considerable proportion of the building energy demand is due to energy losses through the windows. Nevertheless, according to literature, to pay attention only to the contribution of windows to the building energy performance, i.e., their influence on energy use during building operation, could result in a partial evaluation. Hence, it is important to consider not only the building energy performance but also the environmental performance of windows, and this not only during the operational stage but along its complete life cycle. Life Cycle Assessment (LCA) according to ISO 14040:2006 and ISO 14044:2006+A1:2018 is one of the most adopted and robust methods to evaluate the environmental performance of products throughout their complete life cycle. This life-cycle based approach avoids the shift of environmental impacts of a life cycle stage to another, allowing to allocate them to the stage in which they originated and to adopt measures that optimize the environmental performance of the product. Moreover, the LCA method is widely implemented in the construction sector to assess whole buildings as well as construction products and materials. LCA is regulated by the European Standards EN 15978:2011, at the building level, and EN 15804:2012+A2:2019, at the level of construction products and materials. In this work, the environmental performance of wooden windows was assessed by implementing the LCA method and adopting primary data. More specifically, the emphasis is given to embedded and operational impacts. Furthermore, correlations are made between these environmental impacts and aspects such as type of wood and window transmittance. In the particular case of the operational impacts, special attention is set on the definition of suitable maintenance scenarios that consider the potential climate influence on the environmental impacts. For this purpose, a literature review was conducted, and expert consultation was carried out. The study underlined the variability of the embedded environmental impacts of wooden windows by considering different wood types and transmittance values. The results also highlighted the need to define appropriate maintenance scenarios for precise assessment results. It was found that both the service life and the window maintenance requirements in terms of treatment and its frequency are highly dependent not only on the wood type and its treatment during the manufacturing process but also on the weather conditions of the place where the window is installed. In particular, it became evident that maintenance-related environmental impacts were the highest for climate regions with the lowest temperatures and the greatest amount of precipitation.

Keywords: embedded impacts, environmental performance, life cycle assessment, LCA, maintenance stage, operational impacts, wooden windows

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Authors: Sanjeev Gupta, Ankit Prabhakar, K. Rajkumar Singh

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Sunni Dam Hydroelectric Project (382 MW) is a run of river type development with an underground powerhouse, proposed to harness the hydel potential of river Satluj in Himachal Pradesh, India. The project is located in the inner lesser Himalaya between Dhauladhar Range in the south and the higher Himalaya in the north. The project comprises two large underground caverns, a Powerhouse cavern (171m long, 22.5m wide and 51.2m high) and another transformer hall cavern (175m long, 18.7m wide and 27m high) and the rock pillar between the two caverns is 50m. The highly jointed, fractured, anisotropic rock mass is a key challenge in Himalayan geology for an underground structure. The concern for the stability of rock mass increases when weak/shear zones are encountered in the underground structure. In the Sunni Dam project, 1.7m to 2m thick weak/shear zone comprising of deformed, weak material with gauge has been encountered in powerhouse cavern at 70m having dip direction 325 degree and dip amount 38 degree which also intersects transformer hall at initial reach. The rock encountered in the powerhouse area is moderate to highly jointed, pink quartz arenite belonging to the Khaira Formation, a transition zone comprising of alternate grey, pink & white quartz arenite and shale sequence and dolomite at higher reaches. The rock mass is intersected by mainly 3 joint sets excluding bedding joints and a few random joints. The rock class in powerhouse mainly varies from poor class (class IV) to lower order fair class (class III) and in some reaches, very poor rock mass has also been encountered. To study the stability of the underground structure in weak/shear rock mass, a 3D numerical model analysis has been carried out using RS3 software. Field studies have been interpreted and analysed to derive Bieniawski’s RMR, Barton’s “Q” class and Geological Strength Index (GSI). The various material parameters, in-situ characteristics have been determined based on tests conducted by Central Soil and Materials Research Station, New Delhi. The behaviour of the cavern has been studied by assessing the displacement contours, major and minor principal stresses and plastic zones for different stage excavation sequences. For optimisation of the support system, the stability of the powerhouse cavern with different powerhouse orientations has also been studied. The numerical modeling results indicate that cavern will not likely face stress governed by structural instability with the support system to be applied to the crown and side walls.

Keywords: 3D analysis, Himalayan geology, shear zone, underground power house

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Authors: Ujene Ikem Godspower

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Acts of terror perpetrated either by state or non-state actors are considered a social ill and impugn on the collective well-being of the society. As such, there is the need for social reparations, which is meant to ensure the healing of the social wounds resulting from the atrocities committed by errant individuals under different guises. In order to ensure social closure and effectively repair the damages done by anomic behaviors, society must ensure that justice is served and those whose rights and privileges have been denied and battered are given the necessary succour they deserve. With regards to the ongoing terrorism in the Northeast, the moves to rehabilitate and reintegrate Boko Haram members have commenced with the establishment of Operation Safe Corridor,1 and a proposed bill for the establishment of “National Agency for the Education, Rehabilitation, De-radicalisation and Integration of Repentant Insurgents in Nigeria”2. All of which Nigerians have expressed mixed feelings about. Some argue that the endeavor is lacking in ethical decency and justice and totally insults human reasoning. Terrorism and counterterrorism in Nigeria have been enmeshed in gross human rights violations both by the military and the terrorists, and this raises the concern of Nigeria’s ability to fairly and justiciably implement the deradicalization and reintegration efforts. On the other hand, there is the challenge of the community dwellers that are victims of terrorism and counterterrorism and their ability to forgive and welcome back their immediate-past tormentors even with the slightest sense of injustice in the process of terrorists reintegration and rehabilitation. With such efforts implemented in other climes, the Nigeria’s case poses a unique challenge and commands keen interests by stakeholders and the international community due to the aforementioned reasons. It is therefore pertinent to assess the communities’ level of involvement in the cycle of reintegration- hence, the objective of this paper. Methodologically as a part of my larger PhD thesis, this study intends to explore the three different local governments (Michika in Adamawa, Chibok in Borno, and Yunusari in Yobe), all based on the intensity of terrorists attacks. Twenty five in-depth interview will be conducted in the study locations above featuring religious leaders, Community (traditional) leaders, Internally displaced persons, CSOs management officials, and ex-Boko Haram insurgents who have been reintegrated. The data that will be generated from field work will be analyzed using the Nvivo-12 software package, which will help to code and create themes based on the study objectives. Furthermore, the data will be content-analyzed, employing verbatim quotations where necessary. Ethically, the study will take into consideration the basic ethical principles for research of this nature. It will strictly adhere to the principle of voluntary participation, anonymity, and confidentiality.

Keywords: boko haram, reintegration, rehabilitation, terrorism, victimology

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Authors: Anna Krukowska, Tomasz Klimczuk, Adriana Zaleska-Medynska

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Photoactive materials have attracted attention due to their potential application in the degradation of environmental pollutants to non-hazardous compounds in an eco-friendly route. Among semiconductor photocatalysts, tantalates such as potassium tantalate (KTaO3) is one of the excellent functional photomaterial. However, tantalates-based materials are less active under visible-light irradiation, the enhancement in photoactivity could be improved with the modification of opto-eletronic properties of KTaO3 by doping rare earth metal (Er) and further photodeposition of noble metal nanoparticles (Pt). Inclusion of rare earth element in orthorhombic structure of tantalate can generate one high-energy photon by absorbing two or more incident low-energy photons, which convert visible-light and infrared-light into the ultraviolet-light to satisfy the requirement of KTaO3 photocatalysts. On the other hand, depositions of noble metal nanoparticles on the surface of semiconductor strongly absorb visible-light due to their surface plasmon resonance, in which their conducting electrons undergo a collective oscillation induced by electric field of visible-light. Furthermore, the high dispersion of Pt nanoparticles, which will be obtained by photodeposition process is additional important factor to improve the photocatalytic activity. The present work is aimed to study the effect of photocatalytic process of the prepared Er-doped KTaO3 and further incorporation of Pt nanoparticles by photodeposition. Moreover, the research is also studied correlations between photocatalytic activity and physico-chemical properties of obtained Pt/Er-KTaO3 samples. The Er-doped KTaO3 microcomposites were synthesized by a hydrothermal method. Then photodeposition method was used for Pt loading over Er-KTaO3. The structural and optical properties of Pt/Er-KTaO3 photocatalytic were characterized using scanning electron microscope (SEM), X-ray diffraction (XRD), volumetric adsorption method (BET), UV-Vis absorption measurement, Raman spectroscopy and luminescence spectroscopy. The photocatalytic properties of Pt/Er-KTaO3 microcomposites were investigated by degradation of phenol in aqueous phase as model pollutant under visible and ultraviolet-light irradiation. Results of this work show that all the prepared photocatalysis exhibit low BET surface area, although doping of the bare KTaO3 with rare earth element (Er) presents a slight increase in this value. The crystalline structure of Pt/Er-KTaO3 powders exhibited nearly identical positions for the main peak at about 22,8o and the XRD pattern could be assigned to an orthorhombic distorted perovskite structure. The Raman spectra of obtained semiconductors confirmed demonstrating perovskite-like structure. The optical absorption spectra of Pt nanoparticles exhibited plasmon absorption band for main peaks at about 216 and 264 nm. The addition of Pt nanoparticles increased photoactivity compared to Er-KTaO3 and pure KTaO3. Summary optical properties of KTaO3 change with its doping Er-element and further photodeposition of Pt nanoparticles.

Keywords: heterogeneous photocatalytic, KTaO3 photocatalysts, Er3+ ion doping, Pt photodeposition

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Authors: Michael Amankwaa Adu

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Effective communication in the classroom plays a vital role in ensuring successful teaching and learning. In particular, the types of language and speech acts teachers use shape classroom interactions and influence student engagement. This study aims to analyze the speech acts employed by a Career Technology teacher in a junior high school. While much research has focused on speech acts in language classrooms, less attention has been given to how these acts operate in non-language subject areas like technical education. The study explores how different types of speech acts—directives, assertives, expressives, and commissives—are used during three classroom encounters: lesson introduction, content delivery, and classroom management. This research seeks to fill the gap in understanding how teachers of non-language subjects use speech acts to manage classroom dynamics and facilitate learning. The study employs a mixed-methods design, combining qualitative and quantitative approaches. Data was collected through direct classroom observation and audio recordings of a one-hour Career Technology lesson. The transcriptions of the lesson were analyzed using John Searle’s taxonomy of speech acts, classifying the teacher’s utterances into directives, assertives, expressives, and commissives. Results show that directives were the most frequently used speech act, accounting for 59.3% of the teacher's utterances. These speech acts were essential in guiding student behavior, giving instructions, and maintaining classroom control. Assertives made up 20.4% of the speech acts, primarily used for stating facts and reinforcing content. Expressives, at 14.2%, expressed emotions such as approval or frustration, helping to manage the emotional atmosphere of the classroom. Commissives were the least used, representing 6.2% of the speech acts, often used to set expectations or outline future actions. No declarations were observed during the lesson. The findings of this study reveal the critical role that speech acts play in managing classroom behavior and delivering content in technical subjects. Directives were crucial for ensuring students followed instructions and completed tasks, while assertives helped in reinforcing lesson objectives. Expressives contributed to motivating or disciplining students, and commissives, though less frequent, helped set clear expectations for students’ future actions. The absence of declarations suggests that the teacher prioritized guiding students over making formal pronouncements. These insights can inform teaching strategies across various subject areas, demonstrating that a diverse use of speech acts can create a balanced and interactive learning environment. This study contributes to the growing field of pragmatics in education and offers practical recommendations for educators, particularly in non-language classrooms, on how to utilize speech acts to enhance both classroom management and student engagement.

Keywords: classroom interaction, pragmatics, speech acts, teacher communication, career technology

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Authors: Shirley S. Ho

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The advancement and development of social media have inadvertently brought about a new form of bullying – cyberbullying – that transcends across physical boundaries of space. Although extensive research has been conducted in the field of cyberbullying, most of these studies have taken an overwhelmingly empirical angle. Theories guiding cyberbullying research are few. Furthermore, very few studies have explored the association between parental mediation and cyberbullying, with majority of existing studies focusing on cyberbullying victimization rather than perpetration. Therefore, this present study investigates cyberbullying perpetration from a theoretical angle, with a focus on the Theory of Reasoned Action and the Parental Mediation Theory. More specifically, this study examines the direct effects of attitude, subjective norms, descriptive norms, injunctive norms and active mediation and restrictive mediation on cyberbullying perpetration on social media among children and adolescents in Singapore. Furthermore, the moderating role of age on the relationship between parental mediation and cyberbullying perpetration on social media are examined. A self-administered paper-and-pencil nationally-representative survey was conducted. Multi-stage cluster random sampling was used to ensure that schools from all the four (North, South, East, and West) regions of Singapore were equally represented in the sample used for the survey. In all 607 upper primary school children (i.e., Primary 4 to 6 students) and 782 secondary school adolescents participated in our survey. The total average response rates were 69.6% for student participation. An ordinary least squares hierarchical regression analysis was conducted to test the hypotheses and research questions. The results revealed that attitude and subjective norms were positively associated with cyberbullying perpetration on social media. Descriptive norms and injunctive norms were not found to be significantly associated with cyberbullying perpetration. The results also showed that both parental mediation strategies were negatively associated with cyberbullying perpetration on social media. Age was a significant moderator of both parental mediation strategies and cyberbullying perpetration. The negative relationship between active mediation and cyberbullying perpetration was found to be greater in the case of children than adolescents. Children who received high restrictive parental mediation were less likely to perform cyberbullying behaviors, while adolescents who received high restrictive parental mediation were more likely to be engaged in cyberbullying perpetration. The study reveals that parents should apply active mediation and restrictive mediation in different ways for children and adolescents when trying to prevent cyberbullying perpetration. The effectiveness of active parental mediation for reducing cyberbullying perpetration was more in the case of children than for adolescents. Younger children were found to be more likely to respond more positively toward restrictive parental mediation strategies, but in the case of adolescents, overly restrictive control was found to increase cyberbullying perpetration. Adolescents exhibited less cyberbullying behaviors when under low restrictive strategies. Findings highlight that the Theory of Reasoned Action and Parental Mediation Theory are promising frameworks to apply in the examination of cyberbullying perpetration. The findings that different parental mediation strategies had differing effectiveness, based on the children’s age, bring about several practical implications that may benefit educators and parents when addressing their children’s online risk.

Keywords: cyberbullying perpetration, theory of reasoned action, parental mediation, social media, Singapore

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Authors: Hugo Lefeuvre, Jerôme Donnard, Michael Descostes, Sophie Billon, Samuel Duval, Tugdual Oger, Herve Toubon, Paul Sardini

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Spectroscopic autoradiography is a method of interest for geological sample analysis. Indeed, researchers may face different issues such as radioelement identification and quantification in the field of environmental studies. Imaging gaseous ionization detectors find their place in geosciences for conducting specific measurements of radioactivity to improve the monitoring of natural processes using naturally-occurring radioactive tracers, but also for the nuclear industry linked to the mining sector. In geological samples, the location and identification of the radioactive-bearing minerals at the thin-section scale remains a major challenge as the detection limit of the usual elementary microprobe techniques is far higher than the concentration of most of the natural radioactive decay products. The spatial distribution of each decay product in the case of uranium in a geomaterial is interesting for relating radionuclides concentration to the mineralogy. The present study aims to provide spectroscopic autoradiography analysis method for measuring the initial energy of alpha particles with a parallel ionization multiplier gaseous detector. The analysis method has been developed thanks to Geant4 modelling of the detector. The track of alpha particles recorded in the gas detector allow the simultaneous measurement of the initial point of emission and the reconstruction of the initial particle energy by a selection based on the linear energy distribution. This spectroscopic autoradiography method was successfully used to reproduce the alpha spectra from a 238U decay chain on a geological sample at the thin-section scale. The characteristics of this measurement are an energy spectrum resolution of 17.2% (FWHM) at 4647 keV and a spatial resolution of at least 50 µm. Even if the efficiency of energy spectrum reconstruction is low (4.4%) compared to the efficiency of a simple autoradiograph (50%), this novel measurement approach offers the opportunity to select areas on an autoradiograph to perform an energy spectrum analysis within that area. This opens up possibilities for the detailed analysis of heterogeneous geological samples containing natural alpha emitters such as uranium-238 and radium-226. This measurement will allow the study of the spatial distribution of uranium and its descendants in geo-materials by coupling scanning electron microscope characterizations. The direct application of this dual modality (energy-position) of analysis will be the subject of future developments. The measurement of the radioactive equilibrium state of heterogeneous geological structures, and the quantitative mapping of 226Ra radioactivity are now being actively studied.

Keywords: alpha spectroscopy, digital autoradiography, mining activities, natural decay products

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Authors: Yunhan Zhang, Xiaopeng Li, Zhongxiao Peng

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Additive manufacturing (AM) possesses several key characteristics, including high design freedom, energy-efficient manufacturing process, reduced material waste, high resolution of finished products, and excellent performance of finished products. These advantages have garnered widespread attention and fueled rapid development in recent decades. AM has significantly broadened the spectrum of available materials in the manufacturing industry and is gradually replacing some traditionally manufactured parts. Similar to components produced via traditional methods, products manufactured through AM are susceptible to degradation caused by wear during their service life. Given the prevalence of 316L stainless steel (SS) parts and the limited research on the tribological behavior of 316L SS samples or products fabricated using AM technology, this study aims to investigate the degradation process and wear mechanisms of 316L SS disks fabricated using AM technology. The wear mechanisms and tribological performance of these AM-manufactured samples are compared with commercial 316L SS samples made using conventional methods. Additionally, methods to enhance the tribological performance of additive-manufactured SS samples are explored. Four disk samples with a diameter of 75 mm and a thickness of 10 mm are prepared. Two of them (Group A) are prepared from a purchased SS bar using a milling method. The other two disks (Group B), with the same dimensions, are made of Gas Atomized 316L Stainless Steel (size range: 15-45 µm) purchased from Carpenter Additive and produced using Laser Powder Bed Fusion (LPBF). Pin-on-disk tests are conducted on these disks, which have similar surface roughness and hardness levels. Multiple tests are carried out under various operating conditions, including varying loads and/or speeds, and the friction coefficients are measured during these tests. In addition, the evolution of the surface degradation processes is monitored by creating moulds of the wear tracks and quantitatively analyzing the surface morphologies of the mould images. This analysis involves quantifying the depth and width of the wear tracks and analyzing the wear debris generated during the wear processes. The wear mechanisms and wear performance of these two groups of SS samples are compared. The effects of load and speed on the friction coefficient and wear rate are investigated. The ultimate goal is to gain a better understanding of the surface degradation of additive-manufactured SS samples. This knowledge is crucial for enhancing their anti-wear performance and extending their service life.

Keywords: degradation process, additive manufacturing, stainless steel, surface features

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Authors: Prabu Duplex

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Due to stringent emission regulation targets, large-scale transition to renewable energy sources is a global challenge, and wind power plays a significant role in the solution vector. This scenario has led to the construction of offshore wind farms, and several wind farms are planned in the shallow waters where the marine habitat exists. It raises concerns over impacts of underwater noise on marine species, for example bridge constructions in the ocean straits. Dangerous to aquatic life, the environmental organisations say, the bridge would be devastating, since ocean straits are important place of transit for marine mammals. One of the highest concentrations of biodiversity in the world is concentrated these areas. The investigation of ship noise and piling noise that may happen during bridge construction and in operation is therefore vital. Once the source levels are known the receiver levels can be modelled. With this objective this work investigates the key requirement of the software that can model transmission loss in high frequencies that may occur during construction or operation phases. Most propagation models are 2D solutions, calculating the propagation loss along a transect, which does not include horizontal refraction, reflection or diffraction. In many cases, such models provide sufficient accuracy and can provide three-dimensional maps by combining, through interpolation, several two-dimensional (distance and depth) transects. However, in some instances the use of 2D models may not be sufficient to accurately model the sound propagation. A possible example includes a scenario where an island or land mass is situated between the source and receiver. The 2D model will result in a shadow behind the land mass where the modelled transects intersect the land mass. Diffraction will occur causing bending of the sound around the land mass. In such cases, it may be necessary to use a 3D model, which accounts for horizontal diffraction to accurately represent the sound field. Other scenarios where 2D models may not provide sufficient accuracy may be environments characterised by a strong up-sloping or down sloping seabed, such as propagation around continental shelves. In line with these objectives by means of a case study, this work addresses the importance of 3D interactions in underwater acoustics. The methodology used in this study can also be used for other 3D underwater sound propagation studies. This work assumes special significance given the increasing interest in using underwater acoustic modeling for environmental impacts assessments. Future work also includes inter-model comparison in shallow water environments considering more physical processes known to influence sound propagation, such as scattering from the sea surface. Passive acoustic monitoring of the underwater soundscape with distributed hydrophone arrays is also suggested to investigate the 3D propagation effects as discussed in this article.

Keywords: underwater acoustics, naval, maritime, cetaceans

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Authors: Nadia Arikat, Katharine Blain

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During the worst of the COVID pandemic, only essential treatment was provided for patients needing urgent care. With the prolonged extent of the pandemic, there has been a return to more routine referrals for paediatric dentistry advice and treatment for specialist conditions. However, some of these patients and/or their carers may have significant medical issues meaning that attending in-person appointments carries additional risks. This poses an ethical dilemma for clinicians. This project looks at how a secure video conferencing platform (“Near Me”) has been used to assess the need and urgency for in-person new patient visits, particularly for patients and families with additional risks. “Near Me” is a secure online video consulting service used by NHS Scotland. In deciding whether to bring a new patient to the hospital for an appointment, the clinical condition of the teeth together with the urgency for treatment need to be assessed. This is not always apparent from the referral letter. In addition, it is important to judge the risks to the patients and carers of such visits, particularly if they have medical issues. The use and effectiveness of “Near Me” consultations to help decide whether vulnerable paediatric patients should have in-person appointments will be illustrated and discussed using two families: one where the child is medically compromised (Alagille syndrome with previous liver transplant), and the other where there is a medically compromised parent (undergoing chemotherapy and a bone marrow transplant). In both cases, it was necessary to take into consideration the risks and moral implications of requesting that they attend the dental hospital during a pandemic. The option of remote consultation allowed further clinical information to be evaluated and the families take part in the decision-making process about whether and when such visits should be scheduled. These cases will demonstrate how medically compromised patients (or patients with vulnerable carers), could have their dental needs assessed in a socially distanced manner by video consultation. Together, the clinician and the patient’s family can weigh up the risks, with regards to COVID-19, of attending for in-person appointments against the benefit of having treatment. This is particularly important for new paediatric patients who have not yet had a formal assessment. The limitations of this technology will also be discussed. It is limited by internet availability, the strength of the connection, the video quality and families owning a device which allows video calls. For those from a lower socio-economic background or living in some rural areas, this may not be possible or limit its usefulness. For the two patients discussed in this project, where the urgency of their dental condition was unclear, video consultation proved beneficial in deciding an appropriate outcome and preventing unnecessary exposure of vulnerable people to a hospital environment during a pandemic, demonstrating the usefulness of such technology when it is used appropriately.

Keywords: COVID-19, paediatrics, triage, video consultations

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Authors: Nawal Alawad, Passent Ibrahim Tantawi, Mohamed Abdel Salam Ragheb

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Providing customers with quality experiences has been confirmed to be a sustainable, competitive advantage with a distinct financial impact for companies. The success of service providers now relies on their ability to provide customer-centric services. The importance of perceived service quality and customer experience is widely recognized. The focus of this research is in the area of mobile and fixed broadband services. This study is of dual importance both academically and practically. Academically, this research applies a new model investigating the impact of customer experience quality on loyalty based on modifying the multiple-item scale for measuring customers’ service experience in a new area and did not depend on the traditional models. The integrated scale embraces four dimensions: service experience, outcome focus, moments of truth and peace of mind. In addition, it gives a scientific explanation for this relationship so this research fill the gap in such relations in which no one correlate or give explanations for these relations before using such integrated model and this is the first time to apply such modified and integrated new model in telecom field. Practically, this research gives insights to marketers and practitioners to improve customer loyalty through evolving the experience quality of broadband customers which is interpreted to suggested outcomes: purchase, commitment, repeat purchase and word-of-mouth, this approach is one of the emerging topics in service marketing. Data were collected through 412 questionnaires and analyzed by using structural equation modeling.Findings revealed that both outcome focus and moments of truth have a significant impact on loyalty while both service experience and peace of mind have insignificant impact on loyalty.In addition, it was found that 72% of the variation occurring in loyalty is explained by the model. The researcher also measured the net prompters score and gave explanation for the results. Furthermore, assessed customer’s priorities of broadband services. The researcher recommends that the findings of this research will extend to be considered in the future plans of Telecom Egypt Group. In addition, to be applied in the same industry especially in the developing countries that have the same circumstances with similar service settings. This research is a positive contribution in service marketing, particularly in telecom industry for making marketing more reliable as managers can relate investments in service experience directly with the performance closest to income for instance, repurchasing behavior, positive word of mouth and, commitment. Finally, the researcher recommends that future studies should consider this model to explain significant marketing outcomes such as share of wallet and ultimately profitability.

Keywords: broadband services, customer experience quality, loyalty, net promoters score

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Authors: Neelam Kadyan, Pratima Ranga, Yogender

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Indigenous people are the One who are affected by the climate change the most, although there have contributed little to its causes. This is largely a result of their historic dependence on local biological diversity, ecosystem services and cultural landscapes as a source of their sustenance and well-being. Comprising only four percent of the world’s population they utilize 22 percent of the world’s land surface. Despite their high exposure-sensitivity indigenous peoples and local communities are actively responding to changing climatic conditions and have demonstrated their resourcefulness and resilience in the face of climate change. Traditional Indigenous territories encompass up to 22 percent of the world’s land surface and they coincide with areas that hold 80 percent of the planet’s biodiversity. Also, the greatest diversity of indigenous groups coincides with the world’s largest tropical forest wilderness areas in the Americas (including Amazon), Africa, and Asia, and 11 percent of world forest lands are legally owned by Indigenous Peoples and communities. This convergence of biodiversity-significant areas and indigenous territories presents an enormous opportunity to expand efforts to conserve biodiversity beyond parks, which tend to benefit from most of the funding for biodiversity conservation. Tapping on Ancestral Knowledge Indigenous Peoples are carriers of ancestral knowledge and wisdom about this biodiversity. Their effective participation in biodiversity conservation programs as experts in protecting and managing biodiversity and natural resources would result in more comprehensive and cost effective conservation and management of biodiversity worldwide. Addressing the Climate Change Agenda Indigenous Peoples has played a key role in climate change mitigation and adaptation. The territories of indigenous groups who have been given the rights to their lands have been better conserved than the adjacent lands (i.e., Brazil, Colombia, Nicaragua, etc.). Preserving large extensions of forests would not only support the climate change objectives, but it would respect the rights of Indigenous Peoples and conserve biodiversity as well. A climate change agenda fully involving Indigenous Peoples has many more benefits than if only government and/or the private sector are involved. Indigenous peoples are some of the most vulnerable groups to the negative effects of climate change. Also, they are a source of knowledge to the many solutions that will be needed to avoid or ameliorate those effects. For example, ancestral territories often provide excellent examples of a landscape design that can resist the negatives effects of climate change. Over the millennia, Indigenous Peoples have developed adaptation models to climate change. They have also developed genetic varieties of medicinal and useful plants and animal breeds with a wider natural range of resistance to climatic and ecological variability.

Keywords: ancestral knowledge, cost effective conservation, management, indigenous peoples, climate change

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Authors: Tanya Kaur Bedi, Shankha Pratim Bhattacharya

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The US Environmental Protection Agency defines indoor air pollution as “The air quality within and around buildings, especially as it relates to the health and comfort of building occupants”. According to the 2021 report by the Energy Policy Institute at Chicago, Indian residents, a country which is home to the highest levels of air pollution in the world, lose about 5.9 years from life expectancy due to poor air quality and yet has numerous dwellings dependent on natural ventilation. Currently the urban population spends 90% of the time indoors, this scenario raises a concern for occupant health and well-being. This study attempts to demonstrate the causal relationship between the indoor air pollution and its determining aspects. Detailed indoor air pollution audits were conducted in residential buildings located in Kolkata, India in the months of December and January 2021. According to the air pollution knowledge assessment city program in India, Kolkata is also the second most polluted mega-city after Delhi. Although the air pollution levels are alarming year-long, the winter months are most crucial due to the unfavourable environmental conditions. While emissions remain typically constant throughout the year, cold air is denser and moves slower than warm air, trapping the pollution in place for much longer and consequently is breathed in at a higher rate than the summers. The air pollution monitoring period was selected considering environmental factors and major pollution contributors like traffic and road dust. This study focuses on the relationship between the built environment and the spatial-temporal distribution of air pollutants in and around it. The measured parameters include, temperature, relative humidity, air velocity, particulate matter, volatile organic compounds, formaldehyde, and benzene. A total of 56 rooms were audited, selectively targeting the most dominant middle-income group in the urban area of the metropolitan. The data-collection was conducted using a set of instruments positioned in the human breathing-zone. The study assesses the relationship between indoor air pollution levels and factors determining natural ventilation and air pollution dispersion such as surrounding environment, dominant wind, openable window to floor area ratio, windward or leeward side openings, and natural ventilation type in the room: single side or cross-ventilation, floor height, residents cleaning habits, etc.

Keywords: indoor air quality, occupant health, air pollution, architecture, urban environment

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Authors: Amelia Frickey, Timothy (TJ) Sheridan, Angelica Rossi, Bahar Aliakbarian

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The growth of large food supply chains demanded improved end-to-end traceability of food products, which has led to companies being increasingly interested in using smart technologies such as Radio Frequency Identification (RFID)-enabled packaging to track items. As technology is being widely used, there are several technological or economic issues that should be overcome to facilitate the adoption of this track-and-trace technology. One of the technological challenges of RFID technology is its sensitivity to different environmental form factors, including packaging materials and the content of the packaging. Although researchers have assessed the performance loss due to the proximity of water and aqueous solutions, there is still the need to further investigate the impacts of food products on the reading range of RFID tags. However, to the best of our knowledge, there are not enough studies to determine the correlation between RFID tag performance and food beverages properties. The goal of this project was to investigate the effect of the solution properties (pH and conductivity) and different packaging materials filled with food-like water-based solutions on the performance of an RFID tag. Three commercially available ultra high-frequency RFID tags were placed on three different bottles and filled with different concentrations of water-based solutions, including sodium chloride, citric acid, sucrose, and ethanol. Transparent glass, Polyethylneterephtalate (PET), and Tetrapak® were used as the packaging materials commonly used in the beverage industries. Tag readability (Theoretical Read Range, TRR) and sensitivity (Power on Tag Forward, PoF) were determined using an anechoic chamber. First, the best place to attach the tag for each packaging material was investigated using empty and water-filled bottles. Then, the bottles were filled with the food-like solutions and tested with the three different tags and the PoF and TRR at the fixed frequency of 915MHz. In parallel, the pH and conductivity of solutions were measured. The best-performing tag was then selected to test the bottles filled with wine, orange, and apple juice. Despite various solutions altering the performance of each tag, the change in tag performance had no correlation with the pH or conductivity of the solution. Additionally, packaging material played a significant role in tag performance. Each tag tested performed optimally under different conditions. This study is the first part of comprehensive research to determine the regression model for the prediction of tag performance behavior based on the packaging material and the content. More investigations, including more tags and food products, are needed to be able to develop a robust regression model. The results of this study can be used by RFID tag manufacturers to design suitable tags for specific products with similar properties.

Keywords: smart food packaging, supply chain management, food waste, radio frequency identification

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Authors: Vibha Devi, Shabina Khanam

Abstract:

Hemp (Cannabis sativa) possesses a rich content of ω-6 linoleic and ω-3 linolenic essential fatty acid in the ratio of 3:1, which is a rare and most desired ratio that enhances the quality of hemp oil. These components are beneficial for the development of cell and body growth, strengthen the immune system, possess anti-inflammatory action, lowering the risk of heart problem owing to its anti-clotting property and a remedy for arthritis and various disorders. The present study employs supercritical fluid extraction (SFE) approach on hemp seed at various conditions of parameters; temperature (40 - 80) °C, pressure (200 - 350) bar, flow rate (5 - 15) g/min, particle size (0.430 - 1.015) mm and amount of co-solvent (0 - 10) % of solvent flow rate through central composite design (CCD). CCD suggested 32 sets of experiments, which was carried out. As SFE process includes large number of variables, the present study recommends the application of resampling techniques for cross-validation of the obtained data. Cross-validation refits the model on each data to achieve the information regarding the error, variability, deviation etc. Bootstrap and jackknife are the most popular resampling techniques, which create a large number of data through resampling from the original dataset and analyze these data to check the validity of the obtained data. Jackknife resampling is based on the eliminating one observation from the original sample of size N without replacement. For jackknife resampling, the sample size is 31 (eliminating one observation), which is repeated by 32 times. Bootstrap is the frequently used statistical approach for estimating the sampling distribution of an estimator by resampling with replacement from the original sample. For bootstrap resampling, the sample size is 32, which was repeated by 100 times. Estimands for these resampling techniques are considered as mean, standard deviation, variation coefficient and standard error of the mean. For ω-6 linoleic acid concentration, mean value was approx. 58.5 for both resampling methods, which is the average (central value) of the sample mean of all data points. Similarly, for ω-3 linoleic acid concentration, mean was observed as 22.5 through both resampling. Variance exhibits the spread out of the data from its mean. Greater value of variance exhibits the large range of output data, which is 18 for ω-6 linoleic acid (ranging from 48.85 to 63.66 %) and 6 for ω-3 linoleic acid (ranging from 16.71 to 26.2 %). Further, low value of standard deviation (approx. 1 %), low standard error of the mean (< 0.8) and low variance coefficient (< 0.2) reflect the accuracy of the sample for prediction. All the estimator value of variance coefficients, standard deviation and standard error of the mean are found within the 95 % of confidence interval.

Keywords: resampling, supercritical fluid extraction, hemp oil, cross-validation

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Authors: Praniil Nagaraj

Abstract:

This paper proposes a method to collect homeless data using crowdsourcing and presents an approach to analyze the data, demonstrating its potential to strengthen existing and future policies aimed at promoting socio-economic equilibrium. This paper's contributions can be categorized into three main areas. Firstly, a unique method for collecting homeless data is introduced, utilizing a user-friendly smartphone app (currently available for Android). The app enables the general public to quickly record information about homeless individuals, including the number of people and details about their living conditions. The collected data, including date, time, and location, is anonymized and securely transmitted to the cloud. It is anticipated that an increasing number of users motivated to contribute to society will adopt the app, thus expanding the data collection efforts. Duplicate data is addressed through simple classification methods, and historical data is utilized to fill in missing information. The second contribution of this paper is the description of data analysis techniques applied to the collected data. By combining this new data with existing information, statistical regression analysis is employed to gain insights into various aspects, such as distinguishing between unsheltered and sheltered homeless populations, as well as examining their correlation with factors like unemployment rates, housing affordability, and labor demand. Initial data is collected in San Francisco, while pre-existing information is drawn from three cities: San Francisco, New York City, and Washington D.C., facilitating the conduction of simulations. The third contribution focuses on demonstrating the practical implications of the data processing results. The challenges faced by key stakeholders, including charitable organizations and local city governments, are taken into consideration. Two case studies are presented as examples. The first case study explores improving the efficiency of food and necessities distribution, as well as medical assistance, driven by charitable organizations. The second case study examines the correlation between micro-geographic budget expenditure by local city governments and homeless information to justify budget allocation and expenditures. The ultimate objective of this endeavor is to enable the continuous enhancement of the quality of life for the underprivileged. It is hoped that through increased crowdsourcing of data from the public, the Generosity Curve and the Need Curve will intersect, leading to a better world for all.

Keywords: crowdsourcing, homelessness, socio-economic policies, statistical analysis

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Authors: Margarida Porfírio Tomás, Paula Pereira, José Manuel Palma Oliveira

Abstract:

The decline in employment rates across sectors like industry and construction is exacerbated by an aging workforce. This has far-reaching implications for the economy, including skills gaps, labour shortages, productivity challenges due to physical limitations, and workplace safety concerns. To sustain the workforce and pension systems, technology plays a pivotal role. Robots provide valuable support to human workers, and effective human-robot interaction is essential. FORTIS, a Horizon project, aims to address these challenges by creating a comprehensive Human-Robot Interaction (HRI) solution. This solution focuses on multi-modal communication and multi-aspect interaction, with a primary goal of maintaining a human-centric approach. By meeting the needs of both human workers and robots, FORTIS aims to facilitate efficient and safe collaboration. The project encompasses three key activities: 1) A Human-Centric Approach involving data collection, annotation, understanding human behavioural cognition, and contextual human-robot information exchange. 2) A Robotic-Centric Focus addressing the unique requirements of robots during the perception and evaluation of human behaviour. 3) Ensuring Human-Robot Trustworthiness through measures such as human-robot digital twins, safety protocols, and resource allocation. Factor Social, a project partner, will analyse psycho-physiological signals that influence human factors, particularly in hazardous working conditions. The analysis will be conducted using a combination of case studies, structured interviews, questionnaires, and a comprehensive literature review. However, the adoption of novel technologies, particularly those involving human-robot interaction, often faces hurdles related to acceptance. To address this challenge, FORTIS will draw upon insights from Social Sciences and Humanities (SSH), including risk perception and technology acceptance models. Throughout its lifecycle, FORTIS will uphold a human-centric approach, leveraging SSH methodologies to inform the design and development of solutions. This project received funding from European Union’s Horizon 2020/Horizon Europe research and innovation program under grant agreement No 101135707 (FORTIS).

Keywords: skills gaps, productivity challenges, workplace safety, human-robot interaction, human-centric approach, social sciences and humanities, risk perception

Procedia PDF Downloads 51

Authors: Austin Vander Wel, Katherin Vargas Henao

Abstract:

Washington, DC, is a city in which Spanish, along with several other minority languages, is prevalent not only among tourists but also those living within city limits. In response to this linguistic diversity and DC’s adoption of the Language Access Act in 2004, the Washington Metropolitan Area Transit Authority (WMATA) committed to addressing the need for equal linguistic representation and established a five-step plan to provide the best multilingual information possible for public transportation users. The current study, however, strongly suggests that this de jure policy does not align with the reality of Spanish’s representation on DC public transportation–although perhaps doing so in an unexpected way. In order to investigate Spanish’s de facto representation and how it contrasts with de jure policy, this study implements a linguistic landscapes methodology that takes critical language-policy as its theoretical framework (Tollefson, 2005). Specifically concerning de facto representation, it focuses on the discrepancies between digital spaces and the actual physical spaces through which users travel. These digital vs. in situ conditions are further analyzed by separately addressing aural and visual modalities. In digital spaces, data was collected from WMATA’s website (visual) and their bilingual hotline (aural). For in situ spaces, both bus and metro areas of DC public transportation were explored, with signs comprising the visual modality and recordings, driver announcements, and interactions with metro kiosk workers comprising the aural modality. While digital spaces were considered to successfully fulfill WMATA’s commitment to representing Spanish as outlined in the de jure policy, physical spaces show a large discrepancy between what is said and what is done, particularly regarding the bus system, in addition to the aural modality overall. These discrepancies in situ spaces place Spanish speakers at a clear disadvantage, demanding additional resources and knowledge on the part of residents with limited or no English proficiency in order to have equal access to this public good. Based on our critical language-policy analysis, while Spanish is represented as a right in the de jure policy, its implementation in situ clearly portrays Spanish as a problem since those seeking bilingual information can not expect it to be present when and where they need it most (Ruíz, 1984; Tollefson, 2005). This study concludes with practical, data-based steps to improve the current situation facing DC’s public transportation context and serves as a model for responding to inadequate enactment of de jure policy in other language policy settings.

Keywords: Urban landscape, language access, critical-language policy, spanish, public transportation

Procedia PDF Downloads 72