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NON-INVASIVE PPG-BASED ESTIMATION OF BLOOD GLUCOSE LEVEL
Get PDFThis paper focuses on non-invasive blood glucose determination using photoplethysmographic (PPG) signals, which is crucial for managing diabetes. Diabetes stands as one of the world’s major chronic diseases. Untreated diabetes frequently leads to fatalities. Current self-monitoring techniques for measuring diabetes require invasive procedures such as blood or bodily fluid sampling, which may be very uncomfortable. Hence, there is an opportunity for non-invasive blood glucose monitoring through smart devices capable of measuring PPG signals. The primary goal of this research was to propose methods for glycemic classification into two groups (low and high glycemia) and to predict specific glycemia values using machine learning techniques. Two datasets were created by measuring PPG signals from 16 individuals using two different smart devices – a smart wristband and a smartphone. Simultaneously, the reference blood glucose levels were invasively measured using a glucometer. The PPG signals were preprocessed, and 27 different features were extracted. With the use of feature selection, only 10 relevant features were chosen. Numerous machine learning models were developed. Random Forest (RF) and Support Vector Machine (SVM) with the radial basis function (RBF) kernel performed best in classifying PPG signals into two groups. These models achieved an accuracy of 76% (SVM) and 75% (RF) on the smart wristband test dataset. The functionality of the proposed models was then verified on the smartphone test dataset, where both models achieved similar accuracy: 74% (SVM) and 75% (RF). For predicting specific glycemia values, RF performed best. Mean Absolute Error (MAE) was 1.25 mmol/l on the smart wristband test dataset and 1.37 mmol/l on the smartphone test dataset
Case study: Dosimetric comparison of VMAT, IMRT and 3DCRT techniques for left-sided breast cancer treated in deep inspiration breath-hold
Get PDFThe aim of this case study was to compare 3D conformal radiotherapy (3DCRT) plans for patients treated for left-sided breast cancer (whole breast without positive lymph nodes in deep inspiration breath-hold (DIBH)) to volumetric modulated arc therapy (VMAT) and intensity modulated radiation therapy (IMRT) plans. The original clinical plans used tangential field-in-field 3DCRT technique with a combination of 6 MV and 18 MV photon beams. VMAT and IMRT plans were based on several previously published techniques and used 6 MV beams. Two patients were included in this case study and 4 plans were created and compared for each one. All plans were compared in terms of tumour coverage, gradient measure and conformity index, doses to organs at risk (OARs), the volume of body receiving 5 Gy and also the number of Monitor Units (MUs). While better tumour coverage and conformity was achieved with IMRT and VMAT plans, OARs were better spared with the 3DCRT technique, which also resulted in the lowest dose bath and number of MUs
DETERMINATION OF DESIGN PARAMETERS OF ASPHALT PAVEMENT BASED ON PG TECHNOLOGY
Get PDFThe design parameters are one of the important factors to ensure the quality of asphalt pavement design. In “Highway Asphalt Pavement Design Specification” (JTGD50-2017), the stander of China, used the asphalt mixture anti-pressure resilience modulus at a single temperature of 20 ℃ as the design metrics. However, asphalt mixture, as a sticky-bullet plastic material, shows different mechanical properties at different temperatures. China is a vast territory, and there are great differences between the high and low temperature value (m and n) of each region. Therefore, it is unreasonable to design asphalt pavement only with the asphalt mixture anti-pressure resilience modulus value at 20 ℃. Studies show that the design parameters using PG technology can improve the high temperature anti-rutting and low temperature cracking performance of asphalt pavement
Induction motor mechanical defect diagnosis using DWT under different loading levels
Get PDFThe information extraction capability of the widely used signal processing tool, FFT for diagnosing induction machines, is commonly used at a constant load or at different levels. The loading level is a major influencing factor in the diagnostic process when the coupled load and the machine come with natural mechanical imperfections, and at a low load, the mechanical faults harmonics are strongly influenced. In this context, the main objective of this work is the detection of the mechanical faults and the study of the effect of the loading level on the induction motor diagnostic process. We have employed a diagnosis method based on discrete wavelet transform (DWT) for the multi-level decomposition of stator current and extracting the fault’s energy stored over a wide frequency range. The proposed approach has been experimentally tested on a faulty machine with dynamic eccentricity and a shaft misalignment for three loading levels. The proposed method is experimentally tested and the results are provided to verify the effectiveness of the fault detection and to point out the importance of the coupled load
Improving QoS in mobile multimedia streaming with SCTP-PQ
Get PDFThe Stream Control Transmission Protocol (SCTP) is often the preferred transport layer protocol in streaming applications. This protocol combines the best aspects of Transmission Control Protocol (TCP) and User Datagram Protocol (UDP), but also offers additional features. SCTP supports multihoming and multi-streaming applications and has a congestion mechanism like TCP. Media streaming consists of different types of frames with different levels of importance. For example, I-frames carry more information than B-frames in Moving Picture Experts Group (MPEG). Usually, MPEG frames are processed using the First-In-First-Out (FIFO) algorithm. In this paper, a four-level priority queue integrated protocol named SCTP Priority Queue (SCTP-PQ) has been developed to reduce jitter and delay in real-time multimedia streaming for mobile devices. As part of the development, priority and retransmitted packets are determined on the sending side and these packets are processed faster by using the priority queue on the receiving side. In this way, the average queue delay of priority packets on the receiving side is reduced by 90 % and the throughput values are increased by an average of 10 times. The developed protocol has been extensively tested and compared with SCTP. The results show that the SCTP-PQ outperforms the standard SCTP in terms of jitter and delay
Geometric approach to solving inverse kinematics of six DOF robot with spherical joints
Get PDFInverse kinematics is a fundamental concept in robotics that plays a crucial role in a robot’s ability to perform tasks. In this contribution, we propose a novel geometric approach based on vector calculus to solve the inverse kinematics problem. The primary advantage of this approach originates from the solutions, which exhibit a linear form and uncoupled equations. To validate the effectiveness and correctness of our proposed method, we constructed a six-degrees-of-freedom robot. This robot is controlled by an Arduino Mega 2650 on which we have implemented the inverse kinematics algorithm. The validation process involved considering various desired trajectories of the end-effector, which were simulated in Matlab and then performed by the physical robot. Importantly, our findings confirm that the end-effector successfully tracks the predefined trajectories. Furthermore, we conducted a comparative analysis between Paul’s method and the results obtained from joint angles using our proposed approach. Interestingly, our study reveals a significant similarity between the two sets of results, reaffirming the accuracy and validity of the approach presented in this study
Deformation rule of bored pile & steel support for deep foundation pit in sandy pebble geology
Get PDFRegarding the whole excavation process of the support system of the Southwest Jiaotong University Station of Chengdu Metro Line 6 (the deep foundation pit bored pile + steel support and support system) as the engineering background, this paper studies the deformation rule of the deep foundation pit bored pile + steel support of the sandy pebble foundation. The deformation rule of this support system, the settlement rule of the ground surface outside the pit, and the rule of the uplift of the loose at the bottom of the pit are studied. A key analysis of the positive corner of the foundation pit is conducted, and the rationality of the optimization of the support scheme is evaluated. This paper provides effective guidance for the subsequent deep foundation pit construction and provides a reference for deep foundation pit construction
Young Transportation Engineers Conference 2022
No full textThe Young Transportation Engineers Conference 2022 was held in Prague, in November 24, 2022.
The conference is focused on the presentation of scientific work of PhD students and young researchers not only from the Czech Technical University in Prague, Faculty of Transportation Sciences. The main objectives of the conference include presenting the results of scientific and research and professional activities of PhD students, increasing awareness of ongoing or upcoming research projects within the Faculty of Transportation Sciences and the possibility of gaining experience with presenting in front of a professionally educated audience for newly starting PhD students. The conference is thus an opportunity to establish new or strengthen existing personal and professional contacts and a meeting place for doctoral students, experts from industry, as well as faculty staff.
The conference key topics were following:
transport infrastructure,
safety of transport and traffic means,
logistics,
economics and management in transport,
information and telecommunication technologies in transport,
air transport operations and management.
Scientific comittee:Tomáš TichýZuzana BělinováTomáš DoktorPavel HrubešPetr KumpoštStanislav NovotnýStanislav PleningerZuzana RadováAlena RybičkováZdeněk Svatý
Local organizing comittee:Luboš NouzovskýMartin JacuraOndřej DoležalMichal DrábekPatrik HoraždovskýMichaela KalivodováPetr RichterJosef MíkJiří RůžičkaMichaela Neuhäuserová
Guarantor of the peer review process:Jiří Růžička
Guarantor of the language editing:Michal Drábe
U SMART ZONE – Creating highly realistic virtual environment for vehicle-in-the-loop simulations
Get PDFDeveloping Advanced Driver Assistance Systems (ADAS) and Autonomous Vehicles (AV) based on machine learning is generally an extensive and costly process. Due to the increasing complexity of autonomous systems, the need for extensive testing and validation arises. In recent years, computer simulation has been used for these purposes. Performing realistic simulations, especially for the purpose of computer vision-based systems, requires a high-quality, almost photorealistic virtual environment. This paper introduces U SMART ZONE, a high-fidelity virtual model of the Severní Terasa district in Ústí nad Labem, Czech Republic comprising of more than 7.5 km of drivable roads with a total area of approximately 1.4 km2 for human-in-the-loop and hardware-in-the-loop (HiL) simulations
Desing of the algorithm, print and analysis of porous structures with modifiable parameters
Get PDFThe purpose of this paper was to create an algorithm able to creating a porous structure with variable properties, print and analyze them. The basic concepts related to it were introduced and the process of creating an algorithm in Rhinoceros software was described. Having a suitable test group of porous structures, it was shown that it is possible to modify their porosity. In the next step, the structures were presented for printing and its effect. The obtained physical models were examined by microtomography. The resulting cross-sections were processed in ImageJ software. Having cross-sections of the original bone and printed structures, it was possible to compare their porosity and the average diameter of the trabeculae in the structure. With this procedure, it is possible to deduce whether it is possible to print accurate structures that will serve as porous bone implants. The resulting differential porosity comparison was 2.0–7.5 %, while the thickness was about 18–35 %