In this paper, MIL-53(Al) was synthesized by solvothermal method and its application as an adsorbent to remove rhodamine B from aqueous solution. The material was characterized using X-ray diffraction, Fourier-transform infrared spectroscopy, nitrogen adsorption-desorption isotherms, and scanning electron microscopy. The results show that the material has a large specific surface area (1028.3 m2/g). The rhodamine B adsorption on MIL-53(Al) occurs very quickly in the first minutes of contact. Two pseudo-first order and pseudo-second order adsorption kinetic models, and two adsorption isotherm models, including Langmuir and Freundlich, were used to analyze the adsorption data.
Abstract: Urban agriculture is a highly concerned issue during the period of rapid urbanization in Vietnam. Research aims to propose a cultivation process for cultivating oyster mushrooms, utilizing coffee grounds from coffee businesses as a resource. This approach promotes circular economy principles, generating economic benefits for households while protecting the environment and being suitable for urban areas. The study conducted experiments on grey oyster mushrooms using different mixtures of coffee grounds and rubber wood sawdust at the following ratios: 0%, 25%, 50%, 75%, and 100% coffee grounds/rubber wood sawdust, filled into bags with a weight of 1.2kg. The research results showed that disease infection rates were mild in the 0% and 25% mixture ratios, while the remaining ratios exhibited moderate to severe infection levels. The highest mushroom yield was observed in the mixture ratio of 25% coffee grounds, with an average number of mushroom ears per bag reaching 29.7grams/bag, the dry weight is 63.8 grams/bag, with an average size ranging from 3 to 14 cm and a moisture content of 79.5%. The fastest colonization speed on the substrate is achieved by 25%, 50% coffee grounds blend, which fully colonizes the bag in a period of 25 to 35 days, the shortest time compared to the 75% and 100% coffee grounds blends, which take 40 to 45 days. The experimental results show that the 25% coffee grounds: 75% rubber sawdust blend is suitable for urban mushroom cultivation models and can be expanded on a large-scale farm, contributing to minimizing environmental pollution, utilizing limited urban land area, and providing high economic efficiency.
In recent times, there has been a rapid surge in the advancement of technologies associated with Unmanned Aerial Vehicles (UAVs), particularly in the domains of sensors, networking, and processing. Consequently, substantial investments from both governments and industries have been directed towards the exploration of UAVs, aiming to enhance their performance for secure and dependable deployments. The evolution of design methodologies and the exploration of UAV systems have transitioned from single UAV applications to encompass multi-UAVs and cooperative UAV systems. These systems necessitate a heightened level of coordination and collaboration to execute tasks, demanding innovative networking models, approaches, and mechanisms tailored for highly mobile nodes, encompassing numerous intricate parameters and constraints.
The present paper provides comprehensive insights and conducts a meticulous examination of UAV communication protocols, networking systems, architectures, and applications. Furthermore, it delves into UAV solutions while underscoring critical technical challenges and unresolved research issues that warrant further investigation and dedicated research and development endeavors. In this paper, we study some problems and solutions for The Command and Control (C2) aspect of UAV communication systems. We also give some directions for research in near future.
This work presents a benchmarking study between Lagamine, an in-house developed finite element (FE) code, and COMSOL Multiphysics® (Comsol) commercial software in thermal analyses to investigate their capability in modeling complex manufacturing processes. For this purpose, two case studies, including a NAFEMS benchmark for heat transfer with convection and a Directed Energy Deposition (DED) of a bulk sample, were used as test cases. The simulation models using Lagamine and Comsol solvers for each case were described. The underlying algorithms and theories, as well as the soft-ware development, are investigated. The computational results indicate slight differ-ences between Lagamine and Comsol solutions in both case studies. For the NAFEMS test case, the results obtained with Comsol solver appear to be less dependent on the mesh size than those obtained with Lagamine. For the DED test case, within the chosen configurations of Lagamine and Comsol codes, the maximum difference in the highest peak temperatures obtained from the two codes is about 20%. From an engineering point of view, it is suggested to determine parameters of the FE model consistently with the selected FE code to provide the best match with experimental observations.
Symbolic images stand for more than simply what appears before the eyes. They represent a deeper meaning behind the image – something. The symbolic images in public communications, and techniques of their application as an instrument of forming desired ideological models within social consciousness, as well as consider principles of social psychology that enable successful application of communication technologies to a target audience by appealing to their image thinking. Applied methods of the research are: sociocultural, historical, and content analysis, this article focuses on analyzing the significance of symbol image in public communication strategies and its impacts on brand building, trust establishment, and fostering a positive interactive environment with the public. Based on lessons drawn from practical public communication activities of Thu Dau Mot University, the article proposes additional measures to enhance the effectiveness of the unit's communication and their potential application to specific cases, contributing to the development of the field of public communication.
Satisfaction has been the central research area in consumer behavior. Particularly in tourism, satisfying tourists promises the success of destinations. Tourists are now seeking for premier experiences at destinations which requires more distinctive tourism products and excellent service quality. Monitoring tourist satisfaction has become more crucial than ever so as for destination managers and stakeholders to plan appropriate strategic development. The study clarifies the concept of visitor satisfaction and how satisfaction is measured in academic practice. This article review, synthesis, and analysis secondary data from previous academic studies. The article begins by providing satisfaction definition, followed by the benefits of achieving customer satisfaction, and finally, the commonly adopted approaches to measure tourist satisfaction is provided. The study focuses on those approaches proposed before the development of internet which data collection process is mainly based on survey. Both merits and demerits of each approach are also discussed.
Through analysis of the DPSIR model, combined with research methods such as field surveys, and survey questionnaires, the author has given the following results: The amount of waste is increasing; Not paying attention to the classification at source, Solid waste collection is still limited; Environmental quality is degraded due to the stench caused by domestic waste in some neighborhoods; The soil environment is polluted due to solid waste treatment that is difficult to decompose; Surface water and groundwater are also leaked due to leachate, wastewater from landfills; The polluted environment has, directly and indirectly, affected the health and production and business activities of the people in the ward, degraded the ecosystem, and lost the urban beauty. The author has proposed solutions to reduce environmental pollution caused by domestic waste such as population policy, establishing collection groups, craft village planning, and applying the circular green model in economic development.
In recent years, society has been evolving rapidly, and contemporary education is being adapted to satisfy people's requirements in accordance with 4.0 trends and the industrial revolution.This gives birth to the definition of Smart University, the study of which seeks to identify the required components for constructing a smart learning environment. The research group analysed nationally and internationally advanced models, proposing a smart university model for Thu Dau Mot University (T-SMARTHS) with smart levels matching the phases established and developed at Thu Dau Mot University.
Activity recognition is one of the preliminary steps in designing and implementing assistive services in smart homes. Such services help identify abnormality or automate events generated while occupants do as well as intend to do their desired Activities of Daily Living (ADLs) inside a smart home environment. However, most existing systems are applied for single-resident homes. Multiple people living together create additional complexity in modeling numbers of overlapping and concurrent activities. In this paper, we introduce a hybrid mechanism between ontology-based and unsupervised machine learning strategies in creating activity models used for activity recognition in the context of multi-resident homes. Comparing to related data-driven approaches, the proposed technique is technically and practically scalable to real-world scenarios due to fast training time and easy implementation. An average activity recognition rate of 95.83% on CASAS Spring dataset was achieved and the average recognition run time per operation was measured as 12.86 mili-seconds.
The paper presents general theory about making small models for studying large machines. Here, the author refers to the design of pile driving and pressing machines. To express ideas, the author presents design drawings presented in three-dimensional perspective. Currently, pile drivers and pile presses are two separate machines, in which their base machine is the same, their working parts are slightly different. The author takes advantage of the slight differences to combine them into one machine, so as to ensure that this machine is able to pile or pile. In addition, the structure of pile making and pressing machines is created by the author, which is somewhat simpler than the current construction and driving machine. This successful study will form the basis for manufacturing a pile driving machine and pile machine into a single machine, greatly reducing the costs of procurement and construction machine use.