Vector Control of Asynchronous Motor of Drive Train Using Speed Controller H∞

This study proposes the speed control of an asynchronous motor (AM) using the Antiwindup design. First, the conventional vector control based on proportional-integral (PI) controllers is developed for a constant speed set point. Then, a driving cycle is based on measurements on the Safi/Rabat motorway in Morocco using a microcontroller equipped with a GPS device. The collected practical speed is used as a speed reference for conventional vector control. The /Antiwindup controller of the direct rotor flow-oriented control is used to improve the performance of conventional vector control and optimize the energy consumption of the drive train. The effectiveness of the proposed control scheme is verified by numerical simulation. The results of the numerical validation of the proposed scheme showed good performance compared to conventional vector control. The speed control systems are analyzed for different operating conditions. These control strategies are simulated in the MATLAB/SIMULINK environment. The simulation results of the improved vector control of the Asynchronous Machine (AM) are used to validate this optimization approach in the dynamic regime, followed by a comparative analysis to evaluate the performance and effectiveness of the proposed approach. A practical model based on a TMS320F28379D embedded board and its reduced voltage inverter (24V) is used to implement the proposed method and verify the simulation results. Doi: 10.28991/ESJ-2022-06-04-012 Full Text: PD

Embryonic paratesticular rhabdomyosarcoma: a case report

INTRODUCTION: An embryonic paratesticular rhabdomyosarcoma is a very rare mesenchymal tumor. It is an intrascrotal tumor that is localized in paratesticular structures such as the epididymis or spermatic cord. Rhabdomyosarcoma is most often observed in children and adolescents, presenting as a painless scrotal mass. CASE PRESENTATION: Our patient was an 18-year-old Moroccan man who presented with a painless left scrotal mass that had evolved over four months. An inguinal orchiectomy was performed. A histological examination of the excised tissue revealed an embryonic rhabdomyosarcoma. Our patient had three sessions of chemotherapy with vincristine, actinomycin C and cyclophosphamide. Each chemotherapy session was conducted over five days, with a cycle of 21 days. Our patient was assessed two months after the last chemotherapy session and demonstrated good clinical improvement. CONCLUSION: Paratesticular rhabdomyosarcoma is a rare aggressive tumor manifesting in children and very young adults. Localized forms have a good prognosis whereas metastatic tumors show very poor results. A well-defined treatment based on surgery and chemotherapy yields good results

The OpenModelica integrated environment for modeling, simulation, and model-based development

OpenModelica is a unique large-scale integrated open-source Modelica- and FMI-based modeling, simulation, optimization, model-based analysis and development environment. Moreover, the OpenModelica environment provides a number of facilities such as debugging; optimization; visualization and 3D animation; web-based model editing and simulation; scripting from Modelica, Python, Julia, and Matlab; efficient simulation and co-simulation of FMI-based models; compilation for embedded systems; Modelica- UML integration; requirement verification; and generation of parallel code for multi-core architectures. The environment is based on the equation-based object-oriented Modelica language and currently uses the MetaModelica extended version of Modelica for its model compiler implementation. This overview paper gives an up-to-date description of the capabilities of the system, short overviews of used open source symbolic and numeric algorithms with pointers to published literature, tool integration aspects, some lessons learned, and the main vision behind its development.Fil: Fritzson, Peter. Linköping University; SueciaFil: Pop, Adrian. Linköping University; SueciaFil: Abdelhak, Karim. Fachhochschule Bielefeld; AlemaniaFil: Asghar, Adeel. Linköping University; SueciaFil: Bachmann, Bernhard. Fachhochschule Bielefeld; AlemaniaFil: Braun, Willi. Fachhochschule Bielefeld; AlemaniaFil: Bouskela, Daniel. Electricité de France; FranciaFil: Braun, Robert. Linköping University; SueciaFil: Buffoni, Lena. Linköping University; SueciaFil: Casella, Francesco. Politecnico di Milano; ItaliaFil: Castro, Rodrigo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; ArgentinaFil: Franke, Rüdiger. Abb Group; AlemaniaFil: Fritzson, Dag. Linköping University; SueciaFil: Gebremedhin, Mahder. Linköping University; SueciaFil: Heuermann, Andreas. Linköping University; SueciaFil: Lie, Bernt. University of South-Eastern Norway; NoruegaFil: Mengist, Alachew. Linköping University; SueciaFil: Mikelsons, Lars. Linköping University; SueciaFil: Moudgalya, Kannan. Indian Institute Of Technology Bombay; IndiaFil: Ochel, Lennart. Linköping University; SueciaFil: Palanisamy, Arunkumar. Linköping University; SueciaFil: Ruge, Vitalij. Fachhochschule Bielefeld; AlemaniaFil: Schamai, Wladimir. Danfoss Power Solutions GmbH & Co; AlemaniaFil: Sjolund, Martin. Linköping University; SueciaFil: Thiele, Bernhard. Linköping University; SueciaFil: Tinnerholm, John. Linköping University; SueciaFil: Ostlund, Per. Linköping University; Sueci

Bilateral testicular self-castration due to cannabis abuse: a case report

<p>Abstract</p> <p>Introduction</p> <p>The self-mutilating patient is an unusual psychiatric presentation in the emergency room. Nonetheless, serious underlying psychiatric pathology and drug abuse are important background risk factors. A careful stepwise approach in the emergency room is essential, although the prognosis, follow-up, and eventual rehabilitation can be problematic.</p> <p>We present a unique and original case of bilateral self-castration caused by cannabis abuse.</p> <p>Case Presentation</p> <p>We report a case of a 40-year-old Berber man, who was presented to our emergency room with externalization of both testes using his long fingernails, associated with hemodynamic shock. After stabilization of his state, our patient was admitted to the operating room where hemostasis was achieved.</p> <p>Conclusion</p> <p>The clinical characteristics of self-mutilation are manifold and there is a lack of agreement about its etiology. The complex behavior associated with drug abuse may be one cause of self-mutilation. Dysfunction of the inhibitory brain circuitry caused by substance abuse could explain why this cannabis-addicted patient lost control and self-mutilated. To the best of our knowledge, this is the first case report which presents an association between self-castration and cannabis abuse.</p

Theory of the photothermally generated Seebeck voltage in harmonic regime

In this paper, a general theory of the photothermally induced Seebeck voltage in the harmonic regime is presented. Conditions highlighting coupling effects between temperature and electric fields are reported. In the frequency domain, thermoelectric materials are governed by two regimes separated by a cut-off frequency. Below this point, there is no manifestation of coupling on the voltage response. In its vicinity and beyond, coupling appears through an effective Seebeck coefficient and an effective thermal conductivity. From this last quantity, the figure of merit can be, in principle, theoretically determined from the ratio of thermal conductivities obtained respectively at high and low frequencies or from the maximum value of the complex thermal conductivity argument at the cut-off frequency

Towards an Open-Source Modelica Compiler in Julia

Recently the Julia language has become an option for scientific computing. As of 2020, efforts exist to provide libraries that emulate the equation-based modeling features provided by Modelica or otherwise provide such functionality in Julia. The issue with these approaches is that investment in standardization and libraries would be lost unless standard-complacency is guaranteed. We believe that it is possible to combine features from both by implementing such a compiler in Julia. We argue that this approach would open additional opportunities. One such being the handling of variable structure systems (VSS) within the framework of a Modelica standard-compliant compiler. The other being a proposed compiler architecture reminiscent of LLVM for equation-based object-oriented languages. Using the OpenModelica Compiler as a baseline, we verified the fidelity of our implementation by simulating a selected set of models. While there are performance penalties, we argue that improvements to the frontend would mitigate these issues

Adsorption Studies on the Removal of Textile Effluent over Two Natural Eco-Friendly Adsorbents

This study investigates the possibility of applying an adsorption process using two abundant natural minerals M1 and M2. Without pretreatment or activation, the adsorbents were used to treat real textile wastewater samples (collected from Fez city, Morocco). As a cost-effective alternative, these materials were characterized by different analyses, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray fluorescence (XRF). Chemical oxygen demand (COD) and biological oxygen demand (BOD) were used to characterize the textile wastewater. Additionally, the influence of operating conditions (contact time, adsorbent dosages, and pH) was evaluated. Results show that the adsorption process takes place quickly, reaching the equilibrium at 90 and 160 min for M1 (88% COD) and M2 (79% COD). Both materials show a higher affinity to Cr (39%) and lower affinity to Cu (28%). A pseudo-second-order kinetic model provides the best fit to the experimental adsorption data. Germination tests indicate a low toxicity after the adsorption process. Performance of both materials was compared with that of other literature studies

The Design and Processor-In-The-Loop Implementation of a Super-Twisting Control Algorithm Based on a Luenberger Observer for a Seamless Transition between Grid-Connected and Stand-Alone Modes in Microgrids

The abrupt transfer from grid-connected (GC) to stand-alone (SA) operation modes is one of the major issues that may threaten the stability of a distributed generation (DG) system. Furthermore, if the islanding mode happens, it is vital to take into consideration the load voltages or load current waveforms as soon as feasible. This paper develops an advanced control technique based on a super-twisting sliding mode controller (ST-SMC) for a three-phase inverter operating in both the GC and SA modes. This control scheme is proposed to ensure a smooth transition from the GC to SA mode and enhance the load voltage waveforms under the islanding mode. In addition, to minimize the operational costs of the system and the complexity of the studied model, a digital Luenberger observer (DLO) with a proper design is adopted for estimating the inverter-side current. The control scheme of the whole system switches between a current control mode during the GC mode and a voltage control mode during the SA mode. The super-twisting control algorithm is applied to the outer voltage control loop involved in the cascaded voltage/current control scheme in the SA mode. Simulation tests of a three-phase inverter are performed for the purpose of assessing the suggested control performance by using the PowerSim (PSIM) software and comparing it with a classical PI controller. Furthermore, a processor-in-the-loop (PIL) implementation in a DSP board TMS32F28335 while debugging is conducted using code composer studio 6.2.0. The obtained results show efficient control properties, such as a smooth transition among the microgrid (MG) operating modes, as well as effectiveness and robustness during both the GC and SA operation modes