Papers by Keyword: Monitoring

Abstract: The condition of a dynamic machine (equipment) can be estimated at the current level, by measuring the vibration levels. Each component of a machine produces a vibration with one or more specific frequencies. Knowing the components of the spectrum of frequencies of the global vibration, it is possible to determine which of the components of the moving assembly the problem occurred. Thus, by measuring the vibration, a multitude of defects can be detected, for a wide variety of dynamic machines. Unlike other diagnostic devices, spectrum analyzers have the widest use in the evaluation of vibrations and specific stresses on fixed structures or on rotor blades. Other experiments evaluate the natural frequencies of the rotors, the influence of the cavity of the rotor-stator interaction. Model or prototype studies establish the influence of pressure pulsations at partial load for radial axial turbines [5]. In the work, the vibrational behavior of a Kaplan hydraulic turbine with 6 rotor blades of high power (P=200MW, Dn=9.5m), was analyzed when mechanical failures (wear) appeared after several years of operation, the graphs being taken from the diagnostic system of the studied hydrogen generator.

Abstract: Massive structures are exposed to the risk of high temperatures due to cement hydration. With the requirement for sustainable development, the clinker content of conventionally manufactured cements is being reduced, resulting in the development of blended cements, which are gradually being introduced into production. Therefore, the development of temperatures in massive concrete structures containing modern blended cement is the subject of an experimental program. Its results are evaluated not only in terms of the properties of the resulting concrete, but also in terms of the possibility of concrete production and the technology of mixing. Finally, recommendations are given for the design of concrete mixtures for massive structures. Furthermore, the article deals with the comparison of the measured values with the thermal analysis of the structures.

Abstract: Faced with today's critical issues in the management and maintenance of infrastructures - due to factors such as age, structural complexity and the limitations of traditional inspections - this study systematically addresses the entire set of maintenance issues, proposing the integrated use of innovative digital technologies as an answer. The research presents an advanced methodology based on the synergy between Building Information Modeling (BIM), Internet of Things (IoT) and Machine Learning (ML), with the aim of supporting the predictive and dynamic management of infrastructures through the creation of Digital Twins. In this paper, this methodology is applied to two case studies of bridges in Italy, which are currently being monitored. The application focuses on the initial stages of the process: digital modelling of the works (with the creation of BIM models containing static data), installation of sensors for the collection of dynamic data in real time, and subsequent integration of this information for the generation of a functional Digital Twin. This unified model allows not only the management of warning systems based on predefined thresholds, but also the elaboration of in-depth structural diagnoses to support the planning of maintenance interventions. The proposed methodology also represents a strategic step towards the evolution of advanced predictive models, favouring a more proactive, efficient and sustainable approach to maintenance.

Abstract: Continuous water quality monitoring remains a potential concern because of its connection to human wellbeing and aquatic ecosystem. This study examines seasonal variation of TSS concentration in Lagos Lagoon surface water. The Lagoon is located in South-west coastal region in Nigeria known to be extremely contaminated because of its vulnerable location, increasing human activities and infestation from nearby creeks. The investigation utilized Landsat 8-9 multispectral spatial bands (OLI & TIR) while band combination indices, such as WRI (Water Ratio Index) and NSMI, (Normalized Sediment Material Index) that used blue, red, green, NIR and SWIR Band was utilized respectively. Automated Water Extraction Index (AWEI) was employed for further confirmation of sediment concentration. Linear and nonlinear regression testing was used to analyse the correlation between the remotely sensed data and the in-suit data. Result revealed modest undesirable correlation between the employed indices and the real time in suit data reflecting non alignment relationship. Nonlinear equation testing reported highest = (0.42) which is slightly stronger than the linear case with highest (0.27). The dry season equally reports considerably more total suspended solids and turbid particles than the wet season. The final outcome effectively proved the capability of Landsat improved sensor bands in retrieving TSS in Lagoon surface water.

Abstract: The paper explores the problem of optimizing groundwater sampling in areas affected by multiple rocket launcher systems (MRLS). Taking into account modern challenges to the safety of the population and the environment in the conditions of hostilities, an express method of preliminary zoning of groundwater pollution based on the measurement of electrical conductivity has been proposed. The method is based on modeling the spread of contaminants in combination with cluster analysis of these measurements. The results of the study can be used for operational monitoring of territories affected by hostilities and in management decision-making systems in the field of civil protection.

Abstract: Sterilization is a crucial process in healthcare. The environment in which it is performed plays a critical role and any change in temperature and humidity of the environment can compromise the process. In addition, the water quality is also fundamental since its contamination and hardness can cause high impact damage to surgical material and medical equipment. It is difficult for public hospitals in Honduras to control these processes, environments, and water, possibly due to factors such as limited budgets or lack of knowledge of international guidelines. It is proposed to develop a monitoring system capable of measuring environmental and water quality parameters through the implementation of IoT for sterilization units. A vast literature review and the support provided by experts in the field allowed to establish the success criteria for the development of the prototype. The V methodology was used for the mechatronic design to obtain a complete product. By means of experimentation and finally field tests were carried out to determine the components that would integrate the system and the validation of their measurements. A monitoring system was developed to measure relative humidity, temperature, dust particles and total dissolved solids in the water. These measurements were displayed on a web based Ubidots dashboard for data visualization, storage, and export. Once the measurements were obtained, a comparison with international standards was carried out to demonstrate the importance of environmental monitoring in this area.

Abstract: Water-soluble cutting fluids are routinely used as coolants and lubricants in the metalworking process. The properties of these water-soluble cutting fluids change during operation. In the management of the properties of water-soluble cutting fluids, it is crucial to maintain the concentration within an appropriate range. In typical manufacturing facilities, the concentration of water-soluble cutting fluids is measured using Brix. The commonly used Brix meters are of the sampling type. However, measuring the concentration of cutting fluids in numerous machine tools can be time-consuming. In addition, there has been a recent demand for automated measurement and management of concentration and data accumulation. In recent years, relatively inexpensive automatic Brix meters have become available in Japan. In this study, we tried to continuously measure the concentration of water-soluble cutting fluids using an automatic Brix meter. We installed an automatic Brix meter in a tank that continuously circulates 40L of water-soluble cutting fluid and measured it for several tens of days, confirming that it can measure stably. However, depending on the type of water-soluble cutting fluid, the measurement results may become unstable immediately after starting the measurement. Therefore, it was found that the choice of the water-soluble cutting fluid to be used is also important for the concentration measurement by the automatic Brix meter.

Abstract: Many of the previous studies on cutting properties have compared various steels with a same heat treatment, and there are almost no studies that focus on the differences in heat treatments of a same material. In this report, the influence of different heat treatments on tool wear of high-carbon steel (C55) is experimentally investigated in turning process. This study focused on three heat treatments: quenching and tempering, normalizing, and spheroidization annealing. We divided flank wear into 3 areas (corner, middle area and groove wear) for observation and analyzed each characteristic. It is found that for C55, regardless of heat treatment types, wear at the corner of the insert tip is highly dependent on cutting speed, whereas the dependence is lower where it is far away from the corner. This result is considered to be due to the adhesion that occurs while cutting. Therefore, selecting the cutting speed that minimizes flank wear at the corner can control tool wear and extend tool life. In terms of real-time monitoring for tool replacement, the correlation coefficient between the flank wear and the sensing data (spindle current, feed-axis servo motor current, and cutting sound) is also considered to depend on the adhesion condition at the insert tip. If adhesion occurs, the correlation coefficient is not stable and it’s likely to be difficult to predict wear trend to check the end of a tool life. Adhesion makes tool wear prediction using the sensing data difficult.

Abstract: This prototype of a CO2 sensor with Internet of Things (IoT) offers an affordable solution for measuring carbon dioxide (CO2) concentrations in parts per million (ppm). It utilizes specialized sensors to detect CO2 concentrations in the environment. The prototype combines multiple CO2 measurement sensors with an Arduino microcontroller to process the collected data and provide comprehensible ppm CO2 readings. Additionally, an ESP-32 has been incorporated to enable IoT connectivity, allowing for the transmission of CO2 readings to a cloud platform. This platform displays the most recent readings and maintains a brief history of previous measurements, providing real-time insights into CO2 conditions and a record for analysis. A noteworthy feature of this prototype is its buoy system, which enables operation in aquatic environments while minimizing the risk of submersion, ensuring that the sensor remains on the water’s surface without direct contact with the liquid.

Abstract: An algorithm for predicting the intensity of sorption of gaseous materials released into the atmosphere as a result of an accident is proposed. The algorithm consists of three hierarchical levels: monitoring the parameters of gaseous material emission, predicting the consequences of gaseous material emission before and after sorption, and making a management decision. The first hierarchical level includes 4 blocks: obtaining information from the chemical reconnaissance group and the facility representative on the type, amount of hazardous gaseous materials, release intensity and scale of the accident; obtaining information from the hydrometeorological service on temperature, atmospheric pressure, wind direction and speed in the accident area; processing the information received; information on the availability of forces and means for sorption of hazardous gaseous materials. The second hierarchical level also includes 4 blocks: readiness of forces and means for sorption of hazardous gaseous materials; calculation with sorption; calculation without sorption; determination of the boundaries of the chemical damage zone according to the established criteria. At the third hierarchical level, there is 1 block: making a management decision. The software implementation of the proposed algorithm was carried out. The use of the developed algorithm and its software implementation will increase the speed and accuracy of predicting the consequences of the release of hazardous gaseous materials in an accident.