Search Results (1,747)

This article presents a database focused on measuring the experimental performance of a pilot parabolic trough collector (PTC) combined with the meteorological conditions corresponding to the installation site. Water was chosen as the fluid to recirculate through the PTC circuit. The data were recorded between August and September, assuming that global radiation was adequate for use in the concentration process. The database comprises seven experimental tests, which contain variables such as time, inlet temperature, outlet temperature, ambient temperature, global radiation, diffuse radiation, wind direction, wind speed, and volumetric flow rate. Based on the data obtained from this pilot PTC system, it is possible to provide relevant information for the installation and construction of large-scale solar collectors. Furthermore, the climatic conditions considered allow key factors in the design of multiple collectors to be determined, such as the type of arrangement (series or parallel) and manufacturing materials. In addition, the data collected in this study are key to validating future theoretical models of the PTC. Finally, considering the real operating conditions of a PTC in conjunction with meteorological variables could also be useful for predicting the system’s thermal performance using artificial intelligence-based models. Full article

Roadwork zones are high-risk environments where sudden geometric changes, narrowed lanes, and driver unfamiliarity frequently lead to inappropriate speeds. Ensuring safe vehicle speeds in roadwork zones remains a priority due to drivers’ limited perception of risk and frequent non-compliance with temporary limits. This study evaluates the effectiveness of a speed monitoring display (SMD) installed in a nighttime, four-day motorway roadwork site involving a temporary median crossing, where traffic was diverted through a single lane and a chicane-type re-entry. Speed data were collected at two points, 100 and 50 m before the median crossing, labelled as P1 and P2, respectively, during two phases: with standard work zone signage only (Phase 1) and with an SMD added (Phase 2). Results show statistically significant reductions in mean speed after SMD installation at both measurement points, including decreases of 7.09 km/h at P1 and 4.69 km/h at P2, with a greater reduction among heavy vehicles. The percentage of speeding vehicles fell from 95.4% to 81.9% upstream and from 63.4% to 35.7% near the chicane, indicating improved compliance in the most critical section (P2). These findings demonstrate that SMDs can effectively reduce speeds and variability even in very short-term work zones, supporting their integration as low-cost safety measures. Full article

Ladder sleepers were originally developed to reduce maintenance requirements in ballasted tracks by improving load distribution along the rail direction. In Japan, their design generally follows the method used for prestressed concrete sleepers, where dynamic and impact effects induced by train passage are accounted for using an impact factor. However, the impact factor and the length of the unsupported section—which compensates for ballast settlement over time—have not been sufficiently verified for ladder sleeper applications at rail joints, where the load environment is more severe. In this study, ladder sleepers designed following the criteria for general track sections were installed at rail joints in an operating ballasted track. Field measurements of bending moments under train passage were collected over 13 months, and numerical analyses were performed to evaluate the applicability of key design parameters. The impact factor at rail joints remained within a range comparable to that of general sections, confirming that a value of 2 is appropriate. In contrast, the unsupported section tended to extend over time and should be set to ~1.5 times the conventional design length. Accordingly, new ladder sleeper structures suitable for the load environment at rail joints were designed. Full article

Pseudomonas aeruginosa is a key indicator of hygienic and operational deficiencies in swimming pools, particularly in tourist facilities with high and variable user loads. This study reports the results of a four-year regulatory surveillance program (2016–2019) assessing P. aeruginosa contamination in tourist swimming pools in Andalusia, Spain. The program involved 14 hotels and 58 unique installations. A total of 2053 water samples collected from different installation types (outdoor and indoor pools, whirlpools, and cold-plunge pools) were analyzed using standardized ISO methods within the framework of Spanish legislation, and prevalence comparisons were based on proportion tests. The overall prevalence of P. aeruginosa was 5.1%, with marked differences among installation types, reflecting both variation in contamination rates and unequal sampling intensity. Whirlpools consistently showed the highest contamination rates, whereas indoor pools and cold-plunge pools exhibited lower prevalence. No significant differences were observed between chlorine- and bromine-treated pools, and contaminated samples were detected across the full range of disinfectant concentrations, including values within regulatory limits. Temporal analysis revealed that apparent seasonal peaks were installation-dependent rather than reflecting a uniform seasonal trend. Winter detections were confined to indoor pools and whirlpools, which remain operational year-round, while outdoor pools and cold-plunge pools were underrepresented during the low season due to reduced sampling. A marked increase in prevalence was observed in 2019, driven mainly by summer months and high-risk installations; however, this rise was not directly associated with tourist volume and does not support causal inference. These findings highlight the importance of installation-specific and operational factors in shaping P. aeruginosa contamination patterns. The study underscores the need for targeted surveillance strategies focusing on high-risk installations and for cautious interpretation of seasonal patterns in datasets derived from routine regulatory monitoring. Full article

Due to changing weather conditions, productivity needs to be enhanced and resources must be used more efficiently in agriculture. Precision agriculture relies on systems that can gather real-time environmental data to address these issues. However, the high cost of commercial weather stations often limits their adoption in rural areas. This study introduces a low-cost weather station designed for precision agriculture applications. The system consists of three main modules. The first module is the weather station, which gathers data on temperature, relative humidity, barometric pressure, solar radiation, wind speed and direction, and precipitation. It then transmits this data via LoRa communication to the local console module. This console receives the data, displays it on a screen, and sends it through Wi-Fi to the cloud server module. The cloud server presents the information via an interactive interface and is responsible for storing, processing, and analyzing the data records collected. The system was installed in the municipality of Ojocaliente, Zacatecas, Mexico, where performance and validation tests were conducted over a one-month period using sensors and reference measurements to evaluate the accuracy and stability of the data. The results showed high operational reliability and a strong correlation between the recorded values and the reference data. This confirms that the proposed solution provides a scalable, low-cost, and reliable alternative for environmental monitoring in precision agriculture. Full article

The internal temperature of a vehicle is influenced by various factors such as the external environment (temperature, solar radiation, and humidity) and the air conditioning habits of the driver. Even when the air conditioning system is set to a specific temperature, the internal temperature can vary depending on the time, weather, and driver’s manipulation of the system. In this study, we developed and evaluated a deep learning-based vehicle cabin temperature prediction system using CAN (Controller Area Network) data collected from the vehicle and temperature data from thermometers installed on the roof and seats of an electric vehicle (EV). The models used in the temperature prediction system were evaluated by applying various deep learning architectures that consider the characteristics of time series data, and their accuracy was measured using the mean absolute percentage error (MAPE) metric. Additionally, a low-pass filter was applied to the prediction results, which reduced the MAPE from 4.2798% to 4.1433%, indicating an improvement in prediction accuracy. Among the deep learning models, the model with the highest performance achieved an MAPE of 3.5287%, corresponding to an approximate error of 0.88 °C at an actual temperature of 25 °C. The results of this study contribute significantly to enhancing the accuracy and reliability of EV interior temperature predictions, enabling more precise simulations, and improving the thermal comfort and energy efficiency of EVs. The proposed temperature-prediction system is expected to contribute to the comfort of EV users and overall performance of vehicles, thereby strengthening the role of EVs as a sustainable means of transportation. Full article

Short dry spells during the rainy season have become increasingly common in Brazil, reinforcing the need for soil water conservation practices. Plastic mulching can enhance plant water use and mitigate abiotic stress. This study evaluates water use efficiency in terms of soil physical quality, root systems, and photosynthetic performance of citrus plants grown in different Inceptisols. The field experiment, in a randomized block design with a split-plot arrangement, was conducted in Lavras, Brazil, and involved citrus (orange) plants from 2012 to 2014. Undisturbed soil samples were collected at depths of 0.00–0.05, 0.20–0.25, and 0.90–0.95 m, two years after the installation of white plastic (WP), black plastic (BP), and no plastic (NP) mulching treatments in two Inceptisol types, totaling 54 samples. The soil water-retention curve, pore size distribution, and soil physical quality indicators were determined, and root system distribution maps were generated using B-splines. Leaf gas exchange was measured under contrasting precipitation conditions. Inceptisol I showed minimal impact from mulching, except for the bulk density and total porosity, which positively correlated with transpiration under BP. In contrast, in Inceptisol II, WP increased photosynthetic rates under low- and high-precipitation conditions but reduced water use efficiency, correlating positively with macropores and negatively with micropores. Plastic mulching reduces physiological stress in citrus and improves soil physical quality, with WP being the most effective across precipitation levels, particularly in less stable soils. Full article

To address the challenges of high cost, complex deployment, and difficulties in real-time early warning for small landslides near residential areas, a portable and low-cost high-frequency monitoring device based on Micro-Electro-Mechanical Systems (MEMSs) was developed, and an advanced warning algorithm based on anomaly intensity factors was constructed. The device is easy to install and can collect and transmit data to the cloud in real time. Equipped with edge computing capabilities, it can independently analyze data in the absence of network connectivity and transmit real-time early warning information to terminals within a range of 5 km. To verify the performance of the system, a large-scale outdoor landslide simulation test site was constructed, where slope failure was induced through artificial rainfall to obtain the complete process data from deformation to failure. The experimental results demonstrate that the proposed early warning algorithm effectively identified different stability levels, providing warnings up to 13 s prior to catastrophic failure, confirming the high sensitivity and reliability of the device. This study offers a cost-effective and efficient approach to landslide monitoring and early warning, with notable prospects for broader implementation in practice. Full article

This study investigates the influence of array height, irradiance, and wind speed on temperature difference and thermal gradients in photovoltaic (PV) arrays operating in hot, arid conditions. A field experiment was conducted in Mesa, Arizona (latitude 33° N), using two fixed-tilt PV module arrays installed at different elevations—one at 1 m and the other at 2 m above ground level. Each array comprised seven monocrystalline PV modules arranged in a single row with an 18° tilt angle optimized for summer performance. Data were collected between June and September 2025, and the analysis was restricted to 10:00–13:00 h to avoid shading and ensure uniform irradiance exposure on both arrays. Measurements included module backsheet temperatures at the center and edge modules, ambient temperature, plane-of-array (POA) irradiance, and wind speed. By maintaining identical orientation, tilt, and exposure conditions across all PV configurations, the influence of array height was isolated by comparing module operating temperatures between the 1-m and 2-m installations (inter-array comparison). Under the same controlled conditions, the setup also enabled an examination of how the intra-array comparison affects temperature gradients along the PV modules themselves, thereby revealing edge-center thermal non-uniformities. Results indicate that the 2 m array consistently operated 1–3 °C cooler than the 1 m array, confirming the positive impact of elevation on convective cooling. This reduction corresponds to a 0.4–0.9% improvement in module efficiency or power based on standard temperature coefficients of crystalline silicon modules. The 1 m array exhibited a mean edge–center intra-array temperature gradient of −1.54 °C, while the 2 m array showed −2.47 °C, indicating stronger edge cooling in the elevated configuration. The 1 m array displayed a broader temperature range (−7 °C to +3 °C) compared to the 2 m array (−5 °C to +2 °C), reflecting greater variability and weaker convective uniformity near ground level. The intra-array temperature gradient became more negative as irradiance increased, signifying intensified edge cooling under higher solar loading. Conversely, wind speed inversely affected ΔT, mitigating thermal gradients at higher airflow velocities. These findings highlight the importance of array height (inter-array), string length (intra-array), irradiance, and wind conditions in optimizing PV system thermal and electrical performance. Full article

Reducing the fuel consumption of tractors has consistently been a critical challenge that the agricultural machinery industry must address. To investigate the energy consumption during the plowing process of tractors and enhance their economic efficiency, this study conducted comparative experiments under varying plowing speeds and depths. In this experiment, the CAN bus protocol was utilized for the collection of engine operational data, such as rotational speed and fuel flow. A GPS positioning system was adopted to measure the plowing speed of the tractor and combined with the data from the tractor coasting test, and then the energy consumption for operating the plow was determined. In addition, a tension sensor was installed on the three-point hitch to measure the horizontal pull force exerted by the five-share plow during plowing, thereby facilitating the calculation of the energy consumption of agricultural machinery. The findings indicate that when the tractor’s plowing speed is maintained at 5.7 km/h, both the average fuel consumption and the fuel consumption per unit area increase as the plowing depth increases. If the plowing depth is fixed at 23 cm, the average fuel consumption rises with an increase in plowing speed, whereas the fuel consumption per unit area decreases. The experimental data show that during the actual tillage operation of the tractor, the brake thermal efficiency of diesel engines ranges from 21.76% to 28.57%. The energy consumed by agricultural implements accounts for only 11.79% to 17.04% of the total fuel energy. The energy consumed in operating the tractor-drawn plow accounts for merely 7.87% to 13.66% of the diesel engine output energy. Approximately 23.24% to 38.69% of the effective power of the diesel engine is lost during the transmission process. This study provides valuable insights for optimizing the performance of tractors during operation. Full article

Directional frequency analysis and recording (DIFAR) is a widely used sonobuoy in modern underwater acoustic monitoring and surveillance. The sonobuoy is installed in the area of interest, collects underwater data, and transmits the data to nearby aircraft for data analysis. In this process, transmission of a large volume of raw data poses significant challenges due to limited communication bandwidth. To address this problem, existing studies on autoencoder-based methods have drastically reduced amounts of information to be transmitted with moderate data reconstruction errors. However, the information bottleneck inherent in these autoencoder-based methods often leads to significant fidelity degradation. To overcome these limitations, this paper proposes a novel autoencoder method focused on the reconstruction fidelity. The proposed method operates with two key components: Gated Fusion (GF), proven critical for effectively fusing multi-scale features, and Squeeze and Excitation (SE), an adaptive Channel Attention for feature refinement. Quantitative evaluations on a realistic simulated sonobuoy dataset demonstrate that the proposed model achieves up to a 90.36% reduction in spectral mean squared error for linear frequency modulation signals compared to the baseline. Full article

Background: Preventing postoperative infections in hand surgery is an important factor for achieving sustainable results of surgical procedures. To prevent infections, especially when implants are used, preoperative prophylactic antibiotics are applied in adherence to predominantly national guidelines, which are not specifically tailored to hand surgery. However, several studies related to elective soft tissue hand surgery indicate that the preoperative use of antibiotics does not reduce the incidence of postoperative infections. Evidence regarding their efficacy in osteosynthesis of the hand and wrist remains limited. Methods: In this retrospective study, we analyzed 542 adult patients who underwent hand or wrist osteosynthesis between 2016 and 2019 at our university center. They were enrolled in an antibiotic treatment group and a control group without antibiotic treatment. The prophylaxis group (P) underwent surgery in the main operating theater under intravenous anesthesia, whereas the non-prophylaxis group (NP) was treated under WALANT (Wide Awake Local Anesthetic No Tourniquet) in an outpatient operating theater without receiving preoperative antibiotics. Theater construction and installation were otherwise similar, and both were classified as grade 1 theaters. We applied propensity modeling and inverse probability of treatment weighting (IPTW) to achieve balanced treatment groups with respect to risk factors for infection, and we calculated the odds ratio of prophylaxis and infection. Inclusion factors for risk of infection were age, female sex, smoking, diabetes, metabolic disease, inflammatory disease, substance abuse, cardiovascular disease, hepatopathy, renal disease, polytrauma, open fracture, being a manual worker, and occupational accidents. To assess the severity of the cases, we considered whether the fractures were intraarticular, multi-fragmentary, or open, and we collected data on the types of surgical implants that were used. Results: No significant association was found between antibiotic prophylaxis and postoperative infection rate (infection rate P: 3.86%; NP: 3.27%; unadjusted OR: 1.19; adjusted OR after IPTW: 1.09). In terms of risk factors, there was an insignificant trend of higher infection rates in the subgroups smoking, cardiovascular disease, open fracture, occupational accident, and open fixations. Conclusions: In this cohort, routine use of preoperative antibiotics in hand osteosynthesis did not reduce infection rates. The effectiveness of the widespread standardized application of prophylactic antibiotics to reduce the risk of postoperative infections in osteosynthesis of the hand and wrist remains debatable. Our findings set the basis for further prospective studies aiming at clearer guidelines for evidence-based perioperative patient care. Full article

Due to their proximity to track structures, over-track buildings in depot areas may experience adverse vibrations from train operations, which can negatively impact residential comfort and the performance of precision equipment. As the test line typically involves the highest train speeds within the depot and features distinct operating conditions such as constant-speed cruising, accelerating, and braking, this study aims to investigate the influence of different train operation modes on the vibration excitation of over-track high-rise buildings through field measurements at both the central and end sections of the test line. Three operational modes were examined, including cruising, accelerating, and braking. Vibration signals were systematically collected using sensors installed in the free field, on the ground above the building foundation, and at the bases of the shear walls. A time-varying frequency phenomenon was observed at measurement points on the ground above the foundation and at the shear wall bases during train acceleration and braking. Field data indicate that vertical vibrations in the free field at the end section of the test line were significantly greater than those at the middle section, whereas vertical vibrations at the shear wall bases were comparable between the two sections. Notable vibration transmission loss occurs as the vibration propagates into the building structure, with peak values reaching 20 dB at 80 Hz during cruising operations and 35 dB at 125 Hz during acceleration and braking. This study offers valuable insights for assessing train-induced vibration transmission into high-rise over-track buildings. Full article

Smart phones have become an integral part of our lives in modern society, as we carry and use them throughout a day. However, this “body part” may maliciously collect and leak our personal information without our knowledge. When we install mobile applications on our smart phones and grant their permission requests, these apps can use sensors embedded in the smart phones and the stored data to gather and infer our personal information, preferences, and habits. In this paper, we present our preliminary results on quantifying the privacy risk of mobile applications by assessing whether requested permissions are necessary based on app descriptions through textual entailment decided by language models (LMs). We observe that despite incorporating various improvements of LMs proposed in the literature for natural language processing (NLP) tasks, the performance of the trained model remains far from ideal. Full article

Aim: This study investigated the association between frailty levels as determined by the Edmonton Frail Scale and the prevalence of perception of the risk of adverse falls in the domestic and outdoor environment among those older adults who fell so hard that they required hospital treatment (H.) and those older adults who had never encountered such a problem related to falls (C.). Predisposing and triggering factors for falls can be controlled, which is of interest from a public health perspective and, therefore, studied here. Methods: A quantitative cross-sectional study was conducted on a sample of 400 pensioners over 65 years of age from Zagreb region (1.2 million inhabitants, and more than 20% are aged 65+), which involved dividing the population into two subgroups: those who had fallen so hard that they had required hospital treatment (here marked “from Hospital”, or H.) and those who had never encountered such a problem related to falls and are registered as a pensioners in the region (here marked “from Community” or C.). The Edmonton Frail Scale and an additional questionnaire were used to assess the impact of frailty on perceptions of the risk of adverse falls in specific areas of their living environment. Data were collected by nurses using a structured questionnaire face-to-face, and a Chi-square test was used to analyze the dependency, while the z + 4 test evaluated the differences in percentage of those who are aware of a fall risk in case of moderate frailty or severe frailty among these two subgroups. Results: A statistically significant dependency was found between the degree of frailty and the prevalence of the perception of fall risk at least in one of the subgroups H. or C., especially in their homes, moving around their home, climbing up and down stairs, and in the kitchen. Comparing the prevalence of perception of the risk between C. and H., the difference in recognition of risk hazard has been significant for climbing up and down stairs. Among the major problems of non-adapted buildings are slippery floors (for C.), poorly installed or no fence at all (for H.), and inadequate or poor lighting (for H.). The perception of external obstacles (sidewalks, distance from institutions, public lighting) also increases with the deterioration of the functional state. Conclusions: The results confirm the importance of individualized adaptation of residential and public spaces in accordance with the degree of frailty. It is necessary to warn older adults about the risks of falling, both those who have not yet had this experience, as well as those who have suffered the consequences that have led to hospitalization, to reduce the frequency and consequences of falls. Full article