Numerical Solution of Linear Volterra Integral Equation Systems of Second Kind by Radial Basis Functions

In this paper we propose an approximation method for solving second kind Volterra integral equation systems by radial basis functions. It is based on the minimization of a suitable functional in a discrete space generated by compactly supported radial basis functions of Wendland type. We prove two convergence results, and we highlight this because most recent published papers in the literature do not include any. We present some numerical examples in order to show and justify the validity of the proposed method. Our proposed technique gives an acceptable accuracy with small use of the data, resulting also in a low computational cost.

Digital Health and Care Study on Elderly Monitoring

Sustainable technologies are being increasingly used in various areas of human life. While they have a multitude of benefits, they are especially useful in health monitoring, especially for certain groups of people, such as the elderly. However, there are still several issues that need to be addressed before its use becomes widespread. This work aims to clarify the aspects that are of great importance for increasing the acceptance of the use of this type of technology in the elderly. In addition, we aim to clarify whether the technologies that are already available are able to ensure acceptable accuracy and whether they could replace some of the manual approaches that are currently being used. A two-week study with people 65 years of age and over was conducted to address the questions posed here, and the results were evaluated. It was demonstrated that simplicity of use and automatic functioning play a crucial role. It was also concluded that technology cannot yet completely replace traditional methods such as questionnaires in some areas. Although the technologies that were tested were classified as being “easy to use”, the elderly population in the current study indicated that they were not sure that they would use these technologies regularly in the long term because the added value is not always clear, among other issues. Therefore, awareness-raising must take place in parallel with the development of technologies and services.

Modeling of the Scattering Field of an FGM-148 Javelin Anti-Tank Missile in Altair Feko

Introduction. Computer-aided design systems for microwave devices are an effective tool for assessing the backscattering characteristics of complex-shaped objects. However, these calculations are often associated with significant computational costs, especially at large values of the ratio of the characteristic dimensions of the object to the wavelength. The use of asymptotic methods in combination with the mesh coarsening of object partition can significantly reduce these costs. However, in each practical case, this leads to a deterioration in the accuracy of the estimates obtained, which is hard to predict.Aim. Comparative assessment of the results of modeling the scattering field in the CAD of microwave devices using various methods for calculating and detailing the object model in the decimeter and centimeter wavelength ranges.Materials and methods. The research object was an anti-tank guided missile FGM-148 Javelin. The scattering field of Altair FEKO microwave devices was modeled in CAD using the methods of moments and physical optics in the frequency range from 1 to 10 GHz and angles from 0 to 180°. A comparison of one-dimensional backscatter diagrams and radar images obtained using these methods was carried out.Results. For the class of objects under consideration, the method of physical optics provides acceptable accuracy at frequencies of 5 GHz and higher with a step of partitioning the model surface of the order of one centimeter and a total calculation duration of the order of several minutes (Intel Core i5-4460 PC / 3.2 GHz / 8 MB RAM). At lower frequencies, acceptable accuracy and a similar calculation duration are achieved when calculating by the method of moments and a partitioning step of about 20 cm. The possibility of using the Altair FEKO CAD system for modeling radar images of objects with a resolution of at least 20 cm is demonstrated.Conclusion. The results obtained complement the well-known studies in the field of comparative assessment of the time and accuracy characteristics of various methods for calculating the scattering field of objects in the CAD of microwave devices.

AS-Solar, a Tool for Predictive Maintenance of Solar Groundwater Pumping Systems

Energy for water abstraction limits the viability of some irrigable areas. Increasing efficiency and introducing renewable energy can reduce energy cost. Solar pumping is a widely recognized renewable energy solution. These pumping systems suffer special wear out due to sudden changes and for having working conditions far from the nominal points. Thus, monitoring systems are becoming more frequent for maintenance issues. A new decision support system, named AS-Solar, was developed to perform predictive maintenance. This model permits detecting if the source of the anomaly in the pump performance is the pump, the electrical components (motor, variable frequency drive (VFD) or cables) or the pumping pipe. It demands real-time data from the monitoring system and an accurate simulation model, together with an optimization process that helps in the decision making in predictive maintenance. To validate the developed model, it was applied to a complex case study of a solar pumping system of 40 kWp that abstracts groundwater from nearly 200 m deep. This pumping system has a VFD, two lines of cables up to the pump and aggressive water with slimes, which causes different problems in the pumping system. In this case study, the AS-Solar model shows an acceptable accuracy, with a relative error (RE) of the 2.9% in simulated power and 7.9% in simulated discharge.

RAPID TESTING: ANALYSIS OF GNSS RAPID STATIC OBSERVATIONS SUITABILITY FOR ENGINEERING SURVEYS IN URBAN ENVIRONMENTS IN THE TIME OF COVID-19

This study aims to determine which rapid static observation durations would have acceptable accuracy for engineering surveys in urban environments (i.e. Metro Manila) in the time of COVID-19. Due to health concerns caused by the COVID-19 pandemic, Metro Manila has experienced various restrictions in mobility and time spent in public spaces in recent months. This has affected not only the lives and ways of work of the so-called front liners like nurses, doctors, and primary health care workers, but also the public at large which includes Land Surveyors. It is for this reason that this study was conducted, since a balance must be struck between the aim to get accurate engineering survey results and the health and safety of those who are conducting the measurements. Hence, the shortest possible time to conduct rapid static GNSS observation durations with acceptable results must be determined while ensuring that the conduct of the field survey would still be in compliance to the minimum health protocols (i.e. no mass gathering, maintenance of physical distancing, short time of interaction, etc.) set by the national government.For this study, rapid static observations were made at varying time intervals (i.e. 2 minutes, 5 minutes, 10 minutes, 15 minutes, 30 minuntes, 1 hour, and 2 hours) at locations (i.e. open, with minimal obstructions, with significant obstructions) that would simulate archetypal situations when conducting engineering surveys in urban environments. Results were computed using fully constrained least square adjustment and results show that if all GNSS satellites are used in the computations, all time intervals would yield acceptable RMSE values, both for the horizontal (5 mm to 2 cm) and vertical (1 cm to 4 cm), for engineering surveys. However, if not all GNSS signals are available, it is best to use at least two GNSS satellite constellations (i.e. GPS-BeiDou, GPS-Glonass, Glonass-BeiDou) so that rapid static observations with acceptable accuracy can be made for as short as 5 minutes. For the “classical” accuracy standards, all rapid static observation durations yielded Order B relative precisions for the horizontal while most, except for the 30-minute duration, which yielded Third Order level results for the vertical.

Geolocation and diagnostics of trunk pipelines using an active acoustic sensor

The article discusses the issue of determining the location of the main pipeline to identify the deviation of its position from the design due to climatic factors. The possibility of using active sensors capable of operating both as diagnostic devices installed on the main pipeline and as a beacon is investigated, according to the signal of which it is possible to determine the location of this sensor with acceptable accuracy. The optimal operating frequencies are determined by mathematical modeling to ensure the maximum data transfer rate and the required signal-to-noise ratio. The simulation results show the possibility of assessing the attenuation of signals in the ground, as well as determining the limiting range of the method.

Senior Citizens' Health and Social Services in Cebu City

Senior citizens are an important sector in society. Some began their new career during the middle age and many continued a long legacy of productivity and passionate social service living a life of commitment. The aims of the study is to assess the senior citizen’s health and social services in Cebu City. The study uses quantitative and qualitative methods. A statistical computation was used to achieve an acceptable accuracy of findings and the qualitative research double-checks the quantitative research. Furthermore, the qualitative method was used to measure the data since it allowed the participants to give in-depth, detailed answers by personal interview. The Researchers explored the participant’s answers, thus clearing any ambiguity before analyzing and publishing the collected data. The study revealed that the level of implementation of social services for senior citizens was well implemented; The level of perception of health services for senior citizens were provided; The management of senior citizens office has the biggest financial appropriation; that there was no correlation between social services and the perception level since both were labeled not significant. To address the gap a substantial budget shall be allocated to the sixty (60) barangays of Cebu City to be incorporated in OSCA budget. A development plan was proposed as the output of the study.

Wind speed modeling over complex terrain with the artificial neural network in the measure-correlate-predict technique: A case study of Malaysia

This study aimed to create a Malaysian wind map of greater accuracy. Compared to a previous wind map, spatial modeling input was increased. The Genetic Algorithm-optimized Artificial Neural Network Measure–Correlate–Predict method was used to impute missing data, and managed to control over- or under-prediction issues. The established wind map was made more reliable by including surface roughness to simulate wind flow over complex terrain. Validation revealed that the current wind map is 33.833% more accurate than the previous wind map. Furthermore, the correlation coefficient between wind map-simulated data and observed data was high as 0.835. In conclusion, the new and improved wind map for Malaysia simulates data with acceptable accuracy.

Utredning av autismespekterforstyrrelser i BUP – hvor godt samsvar er det mellom instrumenter og endelig klinisk diagnose?

Background: The Developmental, Dimensional and Diagnostic Interview (3Di) and the Autism Diagnostic Observation Schedule (ADOS-2) may be useful when assessing autism spectrum disorder (ASD), but the accuracy of the Norwegian 3Di is not known. Method: We investigated the classification accuracy of the 3Di and the ADOS-2 in identifying clinically diagnosed ASD in 130 participants (mean age 11 years). Results: We found acceptable accuracy in identifying ASD with both the 3Di and ADOS-2 (sensitivities/specificities > 70 %), and highest accuracy (positive likelihood ratio = 17.12) when combining the two instruments, but this gave lower sensitivity (54 %). Conclusions: The 3Di is useful when assessing ASD, and most accurate when combined with information from the ADOS-2. Clinicians should be aware that some children with ASD may be missed by requiring endorsement from both instruments. Keywords: Autism Diagnostic Observation Schedule, inter-rater reliability, sensitivity, specificity, Developmental, Dimensional and Diagnostic Interview

Improving fake news classification using dependency grammar

Fake news is a complex problem that leads to different approaches used to identify them. In our paper, we focus on identifying fake news using its content. The used dataset containing fake and real news was pre-processed using syntactic analysis. Dependency grammar methods were used for the sentences of the dataset and based on them the importance of each word within the sentence was determined. This information about the importance of words in sentences was utilized to create the input vectors for classifications. The paper aims to find out whether it is possible to use the dependency grammar to improve the classification of fake news. We compared these methods with the TfIdf method. The results show that it is possible to use the dependency grammar information with acceptable accuracy for the classification of fake news. An important finding is that the dependency grammar can improve existing techniques. We have improved the traditional TfIdf technique in our experiment.