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In this paper, a new approach to robust optimal design is proposed. The idea is to consider the sensitivity by means of two auxiliary criteria A and D, related to the magnitude and isotropy of the sensitivity, respectively. The optimal design of a switched-reluctance motor is considered as a case study: since the case study exhibits two design criteria, the relevant Pareto front is approximated by means of evolutionary computing.

Electrospinning is an experimental method of the polymer super thin fibres formation using the electrostatic field. The distribution of electrostatic field affects the effectiveness of the electrospinning. In order to analyse the electrostatic field for given technological parameters the 3-D computer model of an electrospinning device must be applied.

Since their discovery by Iijima in 1991 [1], carbon nanotubes have sparked unwavering interest among researchers all over the world. This is due to the unique properties of carbon nanotubes (CNTs). Carbon nanotubes have excellent mechanical and electrical properties with high chemical and thermal stability. In addition, carbon nanotubes have a very large surface area and are hollow inside. This gives a very broad spectrum of nanotube applications, such as in combination with polymers as polymer composites in the automotive, aerospace or textile industries. At present, many methods of nanotube synthesis are known [2, 3, 4, 5, 6]. It is also possible to use carbon nanotubes in biomedical applications [7, 8, 9, 10, 11, 12, 13, 14], including the destruction of cancer cells using iron-filled carbon nanotubes in the hyperthermia process. Computer modelling results of Fe-CNTs induction heating process are presented in the paper. As an object used for computer model creation, Fe-CNTs were synthesized by the authors using CCVD technique.

The aim of the paper is to assess the applicability of a multi-objective biogeography-based optimisation algorithm in MEMS synthesis. In order to test the performances of the proposed method in this research field, the optimal shape design of an electrostatic micromotor, and two different electro-thermo-elastic microactuators are considered as the case studies.

Introduction: Knee Osteoarthritis (KO) is a progressive, chronic disease that damage the joint cartilage of a knee and leads to a changes in a anatomy of the joint. Both surgical and non-surgical methods are used to treat the disease. In this study, we will compare the invasive vs non-invasive methods of KO treatment. Objectives: The review and presentation of the current state of knowledge on Treating Knee Osteoarthritis, comparing surgery vs non-surgery methods. Material and Methods: Review of the studies available on open access sources at PubMed, Google Scholar and National Library of Medicine. Conclusions: Surgery approach for the Knee Osteoarthritis treatment are more durable, have better pain relief and treat casually the OA. Similar effects cannot be reached by non-surgery methods yet. However, there is a big promise in future studies about non-surgery methods, which can also raise a Quality of Life significantly and even avoid or postpone an operation in some groups of patients.

Introduction Trigger finger, also referred to as trigger finger syndrome, is a condition caused by inflammation of the flexor tendons of the fingers and digital pulleys, resulting in pain and restricted movement. This issue affects numerous individuals, particularly the elderly and those who perform repetitive hand motions. Aim The aim of this study is to explore and compare the available treatment options for trigger finger, including rest, splinting, anti-inflammatory medications, physical therapy, steroid injections, and surgical interventions. Both conservative and surgical approaches have their advantages and limitations, and their effectiveness varies depending on the individual patient’s response. State of Knowledge Medical literature describes a variety of treatment methods, ranging from pharmacological approaches and physical therapy to steroid injections and, in more complex cases, surgical interventions. Conservative treatment, often the initial approach, aims to alleviate symptoms and can be effective in the early stages of the condition. Surgery, on the other hand, is considered when conservative treatment fails or in more advanced cases. Summary The choice of treatment for trigger finger should be tailored to the individual needs of the patient and the severity of the condition. Conservative therapy is effective in the early stages but does not always provide long-lasting relief. Surgery, although more invasive, is typically effective in advanced cases and often leads to a quicker restoration of full finger function.

Introduction Disc herniation is a displacement of an intervertebral disc, most often caused by degeneration of its outer layer, the annulus fibrosus. This condition can cause various symptoms such as numbness, pain, muscle weakness or lose of sensation. While many patients can be successfully treated with non-surgical methods, some of them some require surgical intervention. Aim of study The objective of this study is to evaluate both surgical and non-surgical treatment methods for herniated disc and seeks to introduce doctors and patients to the advantages and disadvantages associated with them. State of Knowledge Disk herniation occurs when disk material prolapses beyond intervertebral disk’s space. The symptoms may arise when displaced material start to compress major structures located nearby, such as spinal nerves. The most common causes include age-related degeneration, repetitive movements, obesity, trauma or genetic predisposition. Summary (Conclusion) Disk herniation can be managed with various non-surgical and surgical methods. Conservative treatment should be considered as first line treatment showing high success rate for mild to moderate cases in long term relief and preventing recurrence of symptoms. Surgical options offer better short-term relief for sever and more advanced cases but carry greater risks of side effects and involve longer recovery time. Best approach should be carefully selected based on the severity of symptoms and patient needs.

Introduction: The term "tendinopathy" refers to pathological changes in tendons. The previously used term "tendonitis" does not fully capture the nature of the condition, as inflammatory changes, when present, are secondary to degenerative damage. Tendinopathies are quite common in the general population. Aim: The aim of this review is to characterize various types of tendinopathies, with a focus on both conservative and surgical treatment methods, in order to organize available information that may be helpful for clinicians in their practice. State of Knowledge: Chronic tendinopathies develop as a result of multiple factors. The most significant include improper exercise techniques, excessive strain, and musculoskeletal system abnormalities. Summary (Conclusions): The approach to tendinopathy treatment should vary depending on the patient's clinical condition and provoking factors. Physiotherapy plays the most important role, along with supportive methods such as analgesic pharmacotherapy and cryotherapy. Surgical intervention may be necessary in cases where conservative treatment fails.

Introduction: Developmental Dysplasia of the Hip (DDH) is an anatomical deformation resulting from abnormal formation of the structures that make up the hip joint. Due to abnormal biomechanics patients with hip dysplasia usually develop radiographic osteoarthritis. Aim of the study: Despite the introduction of screening tests in children, DDH remains an issue among adults. For this group of patients, it is essential to begin treatment as early as possible to prevent early-onset osteoarthritis of the hip joint. In adults it is often too late to implement non-invasive methods such as braces or orthoses. Therefore, in this study, we aim to describe other treatment options for adults with DDH, considering both surgical and non-surgical methods. In the following work, we present both the advantages and complications associated with these surgical methods. Additionally, we describe the non-surgical alternative method of progressive resistance training (PRT) and consider the possibilities of combining it with surgical techniques. We also discuss the potential for pharmacological treatment. Material and Methods: Review of studies available through open-access sources on PubMed, Google Scholar, and the National Library of Medicine. Conclusions: The decision to quickly implement an appropriate treatment plan is crucial for improving the patient's quality of life. The choice of treatment method should consider the patient's age and the severity of the disease. Adults with DDH are most often qualified for surgical procedures, which include periacetabular osteotomy (PAO) and total hip replacement (THR). However, for some patients, surgical procedures may be contraindicated or impossible, and in such cases, other non-invasive methods, such as resistance training or appropriate pharmacotherapy, should be considered. Keywords: hip joint, osteoarthritis, surgery, conservative therapy, hip, Surgical Correction

Rotator cuff injuries are a common cause of shoulder pain and dysfunction, resulting from acute trauma or degenerative changes. These injuries, including partial and full-thickness tears, can significantly impair daily activities and reduce quality of life. Treatment options range from conservative measures, such as physical therapy and NSAIDs, to surgical interventions like arthroscopic repair. The choice of treatment depends on factors such as tear size, patient age, and activity level. This review compares the effectiveness of conservative treatment and surgical repair for rotator cuff injuries, focusing on pain relief, functional recovery, and complication rates. Conservative treatment is typically the first-line approach for partial-thickness tears or patients with lower physical demands. Physical therapy and nonsteroidal anti-inflammatory drugs are common modalities that can improve symptoms, particularly for smaller tears. Corticosteroid injections are also used to provide short-term relief, although their long-term benefits are less clear. For larger or full-thickness tears, surgery is often necessary due to the risk of progressive degeneration and persistent symptoms. Arthroscopic repair is particularly beneficial for younger or more active patients, offering superior long-term outcomes in terms of strength and function. Studies indicate that while conservative treatment and surgery may offer similar short-term outcomes for smaller tears, surgery provides better long-term recovery for more extensive injuries. Ultimately, the decision between conservative and surgical treatment should be individualized, considering tear size, patient age, activity level, and overall health. Surgery is recommended for full-thickness tears or when conservative treatment fails to yield sufficient improvement, while conservative management remains effective for many smaller tears.

Introduction Plantar fasciitis is one of the most common reasons for visits to orthopedic clinics. This tendinopathy can cause medial heel pain, stiffness, and tenderness on the plantar surface of the foot. Both conservative and surgical methods are employed in its treatment. Aim The aim of this study is to evaluate selected conservative treatment methods, such as stretching, the use of orthotic insoles, splints, injections, extracorporeal shockwave therapy, and taping, as well as surgical treatment options. The study presents a comparison of these methods in terms of their effectiveness, advantages, and disadvantages. State of Knowledge The plantar fascia is a stiff, connective tissue structure extending along the plantar surface of the foot. Biomechanical load on the fascia, which supports the medial longitudinal arch, can lead to degenerative changes that underlie plantar fasciitis. Symptoms include pain, particularly in the mornings and late evenings, which intensifies with palpation of the heel area. Summary (Conclusions) Conservative treatments for plantar fasciitis are effective in 90% of patients. There are no studies that conclusively demonstrate the superiority of one treatment method over another. Thus, the choice of therapy should be tailored to the patient's lifestyle, activity level, and financial capability. Surgical intervention is necessary in cases of chronic plantar fasciitis which remains resistant to conservative treatments.

The aim of this paper is to determine the conversion accuracy of the Danisense DC200IF (Danisense A/S, Taastrup, Denmark) wideband current transducer for its possible application to test electromagnetic compatibility requirements of the standards IEC 61000-3-2 and IEC 61000-3-12 with the digital power meter Yokogawa WT5000 (Yokogawa Electric Corporation, Tokyo, Japan). To obtain this goal for distorted current of main frequency equal to 50 Hz and in the frequencies range of higher harmonics from 100 Hz to 2500 Hz its amplitude error and phase shift are evaluated. Moreover, the measurable level of higher harmonics with the rated accuracy of the used precision power analyzer is also investigated. Finally, the measuring system is applied to determine the RMS values of current harmonics produced by the audio power amplifier in order to assess its compliance with the standard IEC 61000-3-12.

This paper introduces, explains and illustrates real-life application of virtual training tool for electrical engineering education. The tool gives users the opportunity to interact with and manipulate 3D models of authentic devices. The users have a possibility to compare structural differences between devices, assemble and disassemble the machines and test them under extreme conditions, all of which would not be possible while working with a real device. The 3D devices are fully operational allowing the users to interact with them on every level, including analysis of impact of supply conditions i.e. modify voltage and frequency of a particular motor and monitor changes in performance while still operating. The main goal of this research was to evaluate effectiveness and educational values of the proposed tool. Early studies and feedback from educators and students prove this tool to be a great assistance to process of education, facilitating knowledge acquisition and providing an innovative way to put theory into practice.

This work raises the hypothesis that it is possible to use ferromagnetic carbon nanotubes filled with iron to hyperthermally destroy cancer cells in a radiofrequency electromagnetic field. This paper describes the synthesis process of iron-filled multi-walled carbon nanotubes (Fe-MWCNTs) and presents a study of their magnetic properties. Fe-MWCNTs were synthesized by catalytic chemical vapor deposition (CCVD). Appropriate functionalization properties of the nanoparticles for biomedical applications were used, and their magnetic properties were studied to determine the heat generation efficiency induced by exposure of the particles to an external electromagnetic field. The response of the samples was measured for 45 min of exposure. The results showed an increase in sample temperature that was proportional to concentration. The results of laboratory work were compared to the simulation using COMSOL software. [ABSTRACT FROM AUTHOR]

The aim of this paper is to determine the conversion accuracy of the Danisense DC200IF (Danisense A/S, Taastrup, Denmark) wideband current transducer for its possible application to test electromagnetic compatibility requirements of the standards IEC 61000-3-2 and IEC 61000-3-12 with the digital power meter Yokogawa WT5000 (Yokogawa Electric Corporation, Tokyo, Japan). To obtain this goal for distorted current of main frequency equal to 50 Hz and in the frequencies range of higher harmonics from 100 Hz to 2500 Hz its amplitude error and phase shift are evaluated. Moreover, the measurable level of higher harmonics with the rated accuracy of the used precision power analyzer is also investigated. Finally, the measuring system is applied to determine the RMS values of current harmonics produced by the audio power amplifier in order to assess its compliance with the standard IEC 61000-3-12. [ABSTRACT FROM AUTHOR]

Permanent Magnet (PM) Brushless Direct Current (BLDC) actuators/motors have many advantages over conventional machines, including high efficiency, easy controllability over a wide range of operating speeds, etc. There are many prototypes for such motors; some of them have a very complicated construction, and this ensures their high efficiency. However, in the case of household appliances, the most important thing is simplicity, and, thus, the lowest price of the design and production. This article presents a comparison of computer models of different design solutions for a small PM BLDC motor that uses a rotor in the form of a single ferrite magnet. The analyses were performed by using the finite element method. This paper presents unique self-defined parts of basic PM BLDC actuators. With their help, various design solutions were compared with the PM BLDC motor used in household appliances. The authors proved that the reference device is the lightest one and has a lower cogging torque compared to other actuators, but also has a slightly lower driving torque.

Induction motors are a significant consumer of electricity. Therefore, their energy efficiency level plays a vital role in the world's energy balance. The world's markets strive to produce motors of efficiency class IE3 or IE4 while maximizing the use of wire and magnetic materials. However, high induction values in the motor core can also lead to significant losses in construction materials, especially in the magnetic motor housing. This article aimed to show how it is possible to determine the distribution of the magnetic field and additional losses in the yoke and the cast-iron motor frame using field-circuit methods to model the motor and to refine the analytical method for calculating these losses at the motor design stage. [ABSTRACT FROM AUTHOR]

Soft magnetic composite (SMC) materials made of iron powder are more frequently used in construction of electric actuators and motors because of their advantages with respect to Fe–Si electric steel sheets and because they have almost no powder loss. The study deals with measurements of temperature and torque of a low-power rotary switched reluctance actuator, with reference to a commercial actuator and a prototype actuator characterized by stator and rotor cores made of soft magnetic composite materials. Further power loss analysis was also conducted. To assess the actuators, magnetization characteristics and iron loss vs. magnetic flux density at a given frequency were measured according to IEC standards. Results show that the actuator made of soft magnetic composites exhibits higher efficiency and a lower temperature rise of stator and windings in comparison with the commercial actuator.

During the manufacturing process multi-strand conductors are subject to compressive force and rotation moments. The current distribution in the multi-strand conductors is not uniform and is controlled by the transverse resistivity. This is mainly determined by the contact resistance at the strand crossovers and inter-strand contact resistance. The surface layer properties, and in particular the crystalline structure and degree of oxidation, are key parameters in determining the transverse resistivity. The experimental set-ups made it possible to find the dependence of contact resistivity as a function of continuous working stresses and cable design. A study based on measurements and numerical simulation is made to identify the contact resistivity functions.

In computational electromagnetism there are manyfold advantages when using machine learning methods, because no mathematical formulation is required to solve the direct problem for given input geometry. Moreover, thanks to the inherent bidirectionality of a convolutional neural network, it can be trained to identify the geometry giving rise to the prescribed output field. All this puts the ground for the neural meta-modeling of fields, in spite of different levels of cost and accuracy. In the paper it is shown how CNNs can be trained to solve problems of optimal shape synthesis, with training data sets based on finite-element analyses of electric and magnetic fields. In particular, a concept of multi-fidelity model makes it possible to control both prediction accuracy and computational cost. The shape design of a MEMS design and the TEAM workshop problem 35 are considered as the case studies. [ABSTRACT FROM AUTHOR]

The article presents the analysis of waste heat emission in a typical industrial installation. On the basis of the process monitoring system, periodic analyses of fumes composition, installation process manual and the conducted measurements of the heat fluxes from individual sources emitting heat on the way of natural convection from the devices’ coats and forced convection in the fumes flux were calculated. According to the authors the heat of temperature 140–155 °C and surface power density 860–970 W/m2 emitted by devices’ covers can be reclaimed in ORC techniques, Peltier’s modules and the systems realising Stirling cycle. Part of the waste heat included in fumes, which makes c.a. 76% of the total emission from the installation, should be returned to the process of fuel oxidation, what will reduce the emission by c.a. 18% and the volume of consumed fuel by c.a. 25 m3 CH4/h, according to the presented calculations.

INTRODUCTION:Adherence to treatment, including early treatment discontinuation, in patients with multiple sclerosis or clinically isolated syndrome can be affected by: treatment tolerability, route of drug administration, patient age, disease duration, comorbidities, medical care, and support from their caregivers. AIM:This study aimed to identify the risk factors for poor adherence to Betaferon® treatment, including early discontinuation and omitting doses. MATERIALS AND METHODS:852 adult patients treated with Betaferon participated in this 24-month study. All patients were interviewed using the Risk of Drop-out Questionnaire, the Center for Epidemiologic Studies Depression Scale and the Kurtzke Expanded Disability Status Scale. RESULTS:Patients who stopped therapy were younger (p = 0.003) had a higher mean EDSS score (p = 0.022), higher mean number of relapses (p = 0.017), and reported more often fear of injection (p = 0.027) and adverse events (p = 0.007) than those who did not stop treatment. Comparing patients who stopped therapy in the first and the second year, patients who stopped therapy in the first year of treatment more frequently reported flu-like symptoms and fever, and those who stopped therapy in the second year reported-ineffectiveness of treatment and disease progression. Multivariable logistic regression models confirmed that young age, short disease duration, advanced and progressing disease, and poor Betaferon tolerability were related to premature treatment discontinuation. The risk of omitting a dose during therapy was increased in patients who were working or studying, who had more advanced disease or more adverse events, and in patients who received less support from their caregivers. CONCLUSIONS:Several reasons may lead to problems with adherence to Betaferon treatment. Patients at higher risk of discontinuing treatment need to be identified early to make caregivers' support available to them.

In this paper we present the numerical and experimental results of a design optimization of electromagnetic cantilevers. In particular, a cost-effective technique of evolutionary computing enabling the simultaneous minimization of multiple criteria is applied. A set of optimal solutions are subsequently fabricated and measured. The designed cantilevers are fabricated in arrays, which makes the comparison and measurements of the sensor properties reliable. The microfabrication process, based on the silicon on insulator (SOI) technology, is proposed in order to minimize parasitic phenomena and enable efficient electromagnetic actuation. Measurements on the fabricated prototypes assessed the proposed methodological approach.

The use of a convolutional neural network to develop a surrogate model of the electric field in MEMS devices is proposed. An electrostatic micromotor is considered as the case study. In particular, different CNNs are trained for the prediction of the torque profile and the maximum torque value at a no-load condition and the radial force which could arise in case of the radial displacement of the rotor during motion. The proposed deep learning approach is able to predict the abovementioned quantities with a low error and, in particular, it allows for a decrease in the computational cost, especially in case of optimization problems based on FE models. [ABSTRACT FROM AUTHOR]