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Due to the COVID-19 pandemic, many in-person classes shifted to emergency remote learning, with Zoom being the adopted software choice of communication for many schools. Despite its accessibility, students have expressed fatigue and challenges with conversations using Zoom. Additionally, emergency remote learning has led to decreased interpersonal interactions. Thus, we wondered whether Gather.town, a teleconferencing software with proximity-chat features, might lead to a more positive learning environment than Zoom. We utilized both software in an inquiry and problem-based course, Science of Fictional Characters, at McMaster University during the Fall 2021 semester. We surveyed students’ preference between Gather.town and Zoom across five different domains: engagement, enjoyment, social connectedness, ease of use, and willingness to communicate using each software. Twelve out of 30 enrolled students responded to the survey. Participants reported more engagement (58%), higher enjoyment (58%), and greater social connectedness (92%) to their peers using Gather.town compared to Zoom, despite participants also reporting Zoom being easier to use (92%). The results further revealed no preference towards either software in terms of willingness to communicate. Although our sample size is small, our results nonetheless suggest a software with proximity chat features such as Gather.town could be a potential alternative to Zoom for fostering positive learning environments.

An exhaustive investigation of the effect that urban pollution and heat have on the efficiency of Photovoltaic Thermal (PVT) systems was carried out by means of a comparative field study that included empirical data analysis. Pollutant accumulation on PVT systems in urban environments showed a significant increase over the course of a five-day period. These rates increased from an initial value of 0.03 g/m² to 0.07 g/m², representing a significant increase of 133.33%. As a direct result, the performance of PVT systems saw a considerable decline, with electricity generation falling from an average of 18% to 14% after exposure to urban conditions, a 22.22% loss in efficiency. Concurrently, the examination of urban climate factors revealed correlations between increased pollutant accumulation and higher temperatures (25-30°C), reduced air quality, decreased humidity (50-62%), higher wind speeds (2-4 meters per second), and varying solar irradiation (780-900 watts/m²). The environmental impacts on PVT system performance were further elucidated via correlation analysis, which highlighted probable connections between urban climate and system inefficiency. The research also emphasized the varying effectiveness of cooling interventions and airflow enhancements in reducing the performance losses of PVT systems in urban areas. Our findings underscore the importance of specific cooling tactics and maintenance procedures in maintaining optimal solar energy harvesting performance in urban environments. These results also provide valuable insights into the development of effective mitigation measures for PVT systems in challenging urban conditions. Keywords: Urban pollution, solar panel efficiency, Dust deposition, Environmental factors, Cleaning interventions

Maintaining favorable microclimatic conditions in cultivation facilities is directly linked to the stable operation of the heating system. An emergency shutdown of the heating system in a cultivation facility, especially during the winter, can lead to the death of the plants being grown. Thus, the issue of predicting the thermal regime of the cultivation facility following a cessation of heat supply is practically significant. Research object: cultivation facilities intended for year-round plant growth. Research subject: the patterns of temperature changes in the internal air (both in dimensional and dimensionless forms), the rate of temperature decline, and the loss of thermal energy during an emergency heating system shutdown. Research objective: to predict the thermal regime of the cultivation facility after an emergency shutdown of the heating system. Research methods: classical theory of thermal stability of building envelope structures; the theory of regular thermal regime, according to which the temperature field in all points of the cooling body (in this case, the heating system) changes uniformly, following an exponential law; computational software simulations. Research results: in an industrial greenhouse, the internal air temperature will reach the critical mark of 8 ℃ within 36 minutes after an emergency shutdown of the heating system and will reach zero degrees after 1 hour and 9 minutes. Based on the conducted scientific research, it can be concluded that the cooling of the heating system in an industrial greenhouse occurs quite rapidly, as the heating elements have a high cooling rate. The structural design of the enclosure does not allow for the accumulation of thermal energy. Therefore, heating systems in cultivation facilities intended for year-round plant growth must meet stringent reliability requirements.

The development of products in a variety of industries is now being increasingly influenced by material advancements. Many experts are looking for basic materials that are strong, light, and inexpensive. Solids are often rather thick, whereas light materials are weaker. To attain significant strength while lowering weight, we use composite materials. This work deals with the mixed effects of composites made by hand using an epoxy tar and a hardener along with different fiberes of chopped mate (KC), Kenaf (KA), and Kevlar (KB). Mechanical studies such as tensile (UTS), flexural (FL), impact (IM), and hardness (BHN) were conducted after creating specimens according to standard measurements.

Concrete is a material that is often used in construction in Indonesia. Concrete has the disadvantage that it tends to form cracks. The cracks that form start from small cracks and then enlarge, causing a decrease in quality. Self-healing concrete is a type of concrete that could repair itself with the help of healing agents in the form of bacteria. There are several methods of mixing bacteria into concrete, one of which is by mixing bacteria directly or using a shell which is often called encapsulation. The purpose of this study was to analyze the behavior of the addition of Bacillus Megaterium bacterial encapsulation in terms of compressive strength of concrete with encapsulation proportions of 0%, 2% and 4% by volume weight and using alginate-based shells. The samples used were 15 x 30 cm cylindrical specimens. These specimens were then tested after 7 days and 28 days. Based on test result, it was found that the highest compressive strength was obtained when 2% alginate capsules were added on day 7 and day 28, namely 25.6 MPa and 32.2 MPa. Concrete begun to heal after 2 weeks of curing based on visual observation.

Cracks in concrete beams can significantly affect the performance of reinforced structures. To repair cracks in concrete, Traditional crack repair methods typically involve epoxy injection, but studies have suggested that epoxy may not fully restore the original strength. Therefore, concrete structure repair requires the development of new and more efficient materials. This study focuses on investigating the potential of Bacillus megaterium, a bacterium known for its self-healing properties in concrete. This bacterium has the capability to precipitate minerals like calcium carbonate, which can fill the cracks and increase the strength of concrete. Testing is carried out on reinforced concrete beams with existing cracks, sized at 100 mm x 100 mm x 500 mm. The specimens are divided into two groups, one repaired with epoxy injection and the other with bacterial injection, with varying additions of 10% and 15%. The research results show that the injection process with the addition of 15% bacteria is able to restore approximately 99.72% of the initial strength of the concrete beams. The results of this research contribute to the development of improved repair techniques that can restore the flexural strength of cracked concrete beams and extend the service life of concrete structures.

La utilización de los estudios de montaña requiere de narrativas integradoras para la geoalfabetización sobre paisajes socioecológicos productivos y motiva más investigaciones transdisciplinares en el campo de la montología. Concebimos este artículo como la confluencia de la experiencia individual y el razonamiento colectivo hacia la formación de grupos de investigación sinérgicos que se ocupan de la ciencia de montaña convergente, para hacer avanzar la montología a un nuevo nivel, mediante el cual el pensamiento innovador sobre la ciencia de la sustentabilidad y el desarrollo regenerativo incorpora propuestas alternativas para el mantenimiento, la mejora, o regeneración de las condiciones de vida de los paisajes de montaña. Buscamos utilizar este marco contemporáneo de sustentabilidad y restauración ecológica como el ímpetu para comprender mejor las relaciones de la naturaleza y la cultura, desde una perspectiva transdisciplinar, en montañas habitadas que operan en cuatro dimensiones (largo, ancho, alto y tiempo). El artículo está orientado a potenciar la transversalidad de temáticas en torno a las montañas como sistemas socioecológicos productivos, en una nueva disciplina académica institucionalizada y convergente. Concluimos con un llamado a un desarrollo regenerativo, sustentable y consiliente en las montañas del mundo.

Indonesia is the world’s largest palm oil producer. The Central Statistics Agency (BPS) noted that Indonesia will produce 45.58 million tons of palm oil in 2022. This number has increased by 1.02% compared to the previous year, which reached 45.12 million tons. The palm oil industry comprises on-farms producing fresh fruit bunches (FFB) and processing industries. The processing industry can be divided into two main divisions: factories that crush FFB into crude palm oil (CPO) and factories that process CPO into various refined palm oil products. There are three actors in Indonesia’s palm oil processing business: the private sector, the government (BUMN), and small farmers. This study aims to find organizational and supply chain differences between state-owned palm oil mill companies (BUMN) and private palm oil mills. Data were obtained from documents, publications, agency research reports, or other supporting sources. This study uses a qualitative descriptive analysis method. The results showed differences in production capacity, organizational structure, and supply chain between state-owned and private palm oil mills. However, the two palm oil mills same produce CPO and palm kernels.

Tobacco is produced extensively in Indonesia, with the most excellent yields discovered in Temanggung Regency, located in Central Java. Climate change and increasing tobacco excise affect farmers' income. The study aims to determine the cost, profit, and feasibility of chopped tobacco farming after climate change and rising excise tax. This study involved 74 respondents, selected using simple random sampling, and utilized both primary and secondary data. The feasibility analysis employed the Revenue Cost Ratio (R/C) and Break Even Point (BEP) criteria. The results unveiled that chopped tobacco production was 773 kg/5,625 m2 or 1,374 kg/hectare and climate change had no effect on production. Chopped tobacco farming per growing season for five months required a total cost of IDR 37,013,965. a revenue of IDR 38,551,056, and a profit of IDR 1,537,091. Climate change and rising excise tax on chopped tobacco farming could reduce profits. However, following the R/C and BEP criteria, chopped tobacco farming was feasible.

Central Kalimantan Province is one of the largest provinces in Indonesia with quite a large diversity of genetic resources. This region has various land typologies which consequently have the potential for different biodiversity such as orchids. The research uses a methodology consisting of exploration, collection and collection of data in the field and measurement results, which was carried out in three districts, namely East Kotawaringin, Katingan and Seruyan, from October 2022 to December 2022. The objectives of this research are as follows: (1). Exploration process, (2). Ex-situ and in-situ conservation, (3). Characterization process, (4). Documentation process. From several exploration results, there are five local orchids that can be developed commercially, namely Coelogyne speciosa, Coelogyne foestermanii, Arundina gramminifolia, Bromheadya finlaysoniana, Dendrobium secundum. Selected local orchids have the potential to be developed and can be used in cross-breeding to produce superior new orchid types with attractive colors.

This work defines the concepts of strong efficient dominating set and intuitionistic fuzzy graph. We also introduce an intuitionistic fuzzy graph and a strong efficient dominating number of fuzzy graphs. The strong efficient dominant number in fuzzy graphs has some limitations that are studied, and intuitionistic fuzzy graphs are derived..

The globe has adopted the cloud computing environment, which organizes data and manages space for data storage, processing, and access. This technical development has brought up questions regarding data security and privacy in cloud computing environments, though. The purpose of this abstract is to offer a thorough review of the issues, solutions, and future developments related to data privacy and security in cloud computing. Keeping data private and secure while it is being processed and stored in outside data centres is the main difficulty in cloud computing systems. The abstract discusses the dangers of insider threats, data breaches, and illegal access to sensitive information. It digs further into the legal and compliance criteria that businesses must follow in order to protect user data in the cloud. In result, data privacy and security in cloud computing environments remain critical concerns for organizations and individuals alike. In the survey the overview of how to use cloud storage globally and its challenges, solution and future innovation is well explained. It underscores the importance of robust encryption, access controls, user awareness, and emerging technologies in safeguarding data in the cloud. By addressing these concerns, organizations can leverage the power of cloud computing while maintaining the confidentiality, integrity, and availability of their data.

Stainless steel is a popular material used in various industries due to its excellent corrosion resistance, high strength, and durability. Gas nitriding has been found significantly to improve wear resistance. Chosen for this research work AISI 304 were examined and the impact of gas nitriding to 12 hrs, 24 hrs and 36 hrs were analyzed for better wear behavior. To evaluate the tribological behavior, wear tests were carried out using pin on disc tribometer. The samples were undergone with hardness tests and the microstructures were examined through scanning electron microscope The difference between the compound layer and the diffusion layer were analyzed on the microstructure. The results of untreated samples and nitride samples were compared.

AISI 304 stainless steel categorized under austenitic, has good resistance to corrosion and applicable for high resistance to pitting and stresses. But it has poor hardness, sterngth and resistance to wear. In order to overcome the above problem, various hardening techniques like nitriding, carburizing, carbonitriding, Cyaniding etc are preferred. In this work, aqueous soluted nitriding process is carried out to improve the surface hardness and wear resistance on AISI 304 specimens. Three specimens in cylindrical shape with a diameter of 10mm and length 35mm are treated with salt bath nitriding process for a time period of 45 minutes, 90 minutes, 120 minutes and named as SBN 1, SBN 2, SBN 3 respectively. One specimen is kept untreated to compare the results with treated specimens. After the heat treatment procedure is completed, pin on disc wear testing instrument was used to conduct a wear test at a constant speed and load. All the specimens were subjected to Scanning Electron Microscope test and the results were compared.

Austenitic stainless is having corrosion resistance property, but certain mechanical applications require improved resistance to wear, inferior cavitation, susceptibility to sensitization. These steels have numerous favourable circumstances for great cryogenic - properties, anti-corrosion, and bio-compatibility. So these steels have a broad application in low temperature innovation, saltwater applications, nourishment industry, bio-medicine, petro-chemical handling, and so forth when alloyed with nitrogen, austenitic treated steels has a progressively steady austenite structure, better mechanical properties and better wear opposition, which has animated extraordinary enthusiasm for this exploration work. Many surface hardening techniques are available, the best surface modification technique is chosen for improved service performance. Surface engineering is a technique to alter the surface of a material by mechanical or microchemical method without affecting the material properties. The alterations are done on the surfaces subjected to the liquid nitriding process to produce a hardened surface. Chosen for this research workbased on their wide application, the wear behaviour of AISI 316LN stainless steels was investigated. Of the various surface hardening techniques available, nitriding is chosen, so that these nitrogen gets penetrated into the material, in which hard iron chromium nitrides are formed at the surface level. AISI 316LN specimens were subjected to salt bath nitriding process. The specimens were nitrided to 60 minutes, 120 minutes and 180 minutes respectively. The specimens were undergone with wear tests by standardized tribiological wear machine and finally the metallographic studies were made.

Crosstalk artefacts appear as dark signal lines on MR images that occur due to imperfect multi-slice settings. There is still a good deal of emergence of crosstalk artefacts on T1 of SE and FSE sequence with interleaved slice acquisition methods. This study aims to determine the differences and the optimal value of reduction of crosstalk artefacts against changes in TR on T1 between SE and FSE sequences in interleaved slice acquisition methods. The experiment was carried out by scanning the water phantom with a variation of TR 500ms, 600ms, and 700ms in SE and FSE sequences. An assessment of the reduction of crosstalk artefacts was carried out using SNR values. There is a significant difference in the reduction of crosstalk artefacts between SE sequences and FSE on T1 (p-value = < 0.001). The reduction of crosstalk artefacts in SE sequences with TR values of 600ms and 700ms respectively, were 22.2% and 37.7%. Whereas the FSE sequences were 28.3% and 56%. Optimal crosstalk artefact reduction occurs in FSE sequences of T1 (56%). It is intended to use FSE sequences with TR 700ms on T1 if there are overlapping slices so that the crosstalk artefacts that occur will be reduced optimally.

Present research papers focuses to strength low plastic soil using deep cement mixing technique through model study. Soil column length of 10cm, 20 cm and 30cm was used with varying degree of saturation as 60%, 80% and 100% of OMC to determine settlement characteristics, unconfined compressive strength, modulus of subgrade reaction and modulus of elasticity of raw and treated soil. Cement dosage for UCS test and model plate load test was decided as per guidelines provided in FHWA 13-046 design manual and CDM-LODIC method respectively. Method of deep mixing the soil with cement was adopted from theory given by Filz et.al. (2005). The results depicted the cement deep mixing methodology based on soil particle-cement particle interaction with varying degree of saturation proved the efficacy for low plastic soils and maximum reduction in settlement was observed for 60% degree of saturation for column length of 20 cm. Modulus of elasticity was validated with provisions of FHWA whereas load carrying capacity of soil-cement column was validated with Broms empirical equation.

This study deals with the evaluation of traffic performance at the road network around the old city of Karbala from the southern side, at Al-Tarbia Street and Fatima Al-Zahraa Street, through the evaluation of intersections performance. This is followed by suggestions of some improvement proposals, which vary from changing timing plan, geometric improvement, to change intersection type completely. The study area composed of seven intersections, three intersections are four legs signalized, and the other four are roundabouts. The video recording technique is used to collect the traffic data for 27 approaches. These data are abstracted from video films using EVENT program, and processed by prepared EXCEL sheets. While, the spot speed data for each entire link in the network are collected using pavement marking method. SYNCHRO software was used for evaluation and analysis of signalized intersections, suggestion of best timing plan, and coordination. SIDRA INTERSECTION software was used for evaluation and analysis of both signalized intersections and roundabouts. The best proposal was also evaluated for the target year.

Magnetorheological elastomer (MRE) consists of an elastomer matrix and a Ferro-magnetic ingredient. The mechanical properties of MR elastomers can be reversibly controlled by applying a magnetic field of suitable intensity. The current work focusses on the enhancement of tensile property of RTV (Room Temperature Vulcanization) silicone based elastomer. The influence of Carbonyl iron powder (CIP) content and magnetic field were experimentally investigated. Addition of CIP increases the tensile modulus but it reduces the percentage elongation and tensile strength making it brittle. Under the influence of magnetic field, the enhancement of tensile properties up to 20% content was linear. The behavior above 20% is observed to be non-linear. The onset of non-linear stress-strain behavior is investigated. Regression equation is developed from the experimental data relating percentage content with the mechanical properties of MRE. The developed equation predicted the behavior of 27% MRE with an error of less than 8%. Hyperelastic model developed by Yeoh was fitted to the stress-strain behavior of MRE with minimal error.

An investigation was made to determine the effects of ethanol at ultra-lean effective systems utilizing an experimental study. The present study is planned to develop and evaluate the performance, emission and combustion characteristics of the ultra-lean burn Internal Combustion engine was modified to operate on ethanol blends fuels. The study looked at part throttle, constant speed operation of 0%, 10%, and 15% ethanol blends with gasoline mixtures operating in ultra-lean operating systems. In experiment practice the use of homogeneous lean mixtures in engine has been handicapped by several difficulties. The most serious one is that the flame propagation through mixtures becomes gradually slower as the mixture becomes leaner. The mixture distribution in a multi-cylinder engine is a problem because even small variation in mixture ratio on the linear side will strongly effect power output. Enhancement of lean combustion of homogeneous mixtures can be achieved by (i) using ethanol blends with gasoline (ii) using high-ignition energy (iii) providing high compression ratios (iv) creating high swirl in the combustion chamber.

This paper implements Teaching-Learning based optimization (TLBO) to obtain optimized value of spring stiffness for better ride comfort. Further, this optimized value is then used in a semi-active quarter car setup to remove any discrepancies due to non-optimized spring. This paper also introduces a novel approach to control the Semi-active suspension parameter (damping coefficient) for a better performance. For controlling semi-active parameters, PID controller has been used. PID controller output is fed to the quarter car setup as a damping coefficient. Thus changing the damping coefficient dynamically as the disturbance occurs, and thus improving the ride comfort. The sprung mass acceleration and rattle space of semi-active quarter car has been compared with sprung mass acceleration and rattle space of passive quarter car model to show the difference in results and thereby, results and conclusions are drawn.

Background: In March 2013 Facebook announced it had around 1.1 billion monthly active users, this number has been growing exponentially from 40% in 2011 and it is estimated to pass 70% mark in 2013. Most of these users being young, the impact of Facebook addiction can clearly be expected to alter their lifestyle. Objectives: •To examine the impact Facebook addiction (IV) on the recreational activities (DV). •To identify the effects of Facebook addiction on the well-being of the Indian youth. Methods: Empirical research using descriptive analysis was conducted on more than 100 college students. Findings: Greater percentage of the population is at threat to get addicted or is already addicted to Facebook. Activities affected due to Facebook usage were identified and categorized. Anger, frustration, boredom and sadness were the possible variables reported by respondent incase of forceful reduction of Facebook usage.

Competing Interests: Intérêts concurrents:: Nikki Bozinoff déclare avoir reçu des bourses de recherche de l’Academic Health Sciences Alternate Funding Program (Programme de financement alternatif de l’Académie des sciences de la santé), des Instituts de recherche en santé du Canada et de la communauté philanthropique womenmind (indépendamment du manuscrit soumis). La Dre Bozinoff a reçu une subvention du National Institute on Drug Abuse (Institut national sur la toxicomanie) (R25-DA037756), en appui du présent manuscrit, ainsi que des honoraires du Collège des médecins de famille de l’Ontario pour des activités éducatives et un paiement du Centre de toxicomanie et de santé mentale pour l’élaboration de matériel de perfectionnement professionnel continu indépendamment du présent manuscrit. Aucun autre intérêt concurrent n’a été déclaré.