Mazdak Rad Malek SHahi

  Abstract Biosensors have attracted special attention in recent years as key tools in biomedical, environmental, and pharmaceutical fields. The increasing demand for rapid, accurate, and low-cost diagnostic methods has led researchers to use Field-Effect Transistors, specifically Tunnel Field-Effect Transistors (TFETs). Due to their low power consumption, subthreshold swing of less than 60 mV/decade, and compatibility with nano-scale technologies, these devices are ideal candidates for developing the next generation of biosensors. In this thesis, three different architectures of short-gate TFET-based biosensors, including Continuous-Gate Structure , Multi-Segment Gate Structure , and Fractional-Gate Structure, were designed, simulated, and analyzed. To investigate the effect of dielectric materials on sensor sensitivity, four different dielectric constants (1, 7, 9, and 11) were considered for filling the biosensor cavities. Simulations were performed using the Atlas environment in SILVACO software based on advanced physical models, including Band-to-Band Tunneling (BTBT), SRH and AUGER recombination, and field-dependent mobility models (CONMOB and FLDMOB). Simulation results showed that the choice of architecture and dielectric constant plays a decisive role in the sensitivity and efficiency of biosensors. In the continuous-gate structure, drain current sensitivity decreased from approximately2500 for k=11 to 400 at higher voltages. In the multi-segment gate structure, the initial sensitivity for k=11 was reported at about 600, which decreased to 70 at higher voltages. In the fractional-gate structure, sensitivity for k=11 was over 70 at low voltages and reached about 2 as the drain voltage increased. This comparison indicates that the continuous-gate structure with high dielectric constants offers optimal sensitivity performance, while the fractional-gate structure provides greater stability. The results of this research show that through optimizing gate architecture and selecting high-k dielectric materials, biosensors with higher accuracy and lower power consumption can be developed for real-world environments. These achievements can play a significant role in rapid disease diagnosis, environmental monitoring, and the development of portable medical devices. Keywords: Biosensor, Tunnel Field-Effect Transistor (TFET), Short Gate, Sensitivity, Dielectric Constant, SILVACO Simulation.

كلمات كليدي: تثبيت خاك‌هاي رسي، سيمان پرتلند، الياف تركيبي، الياف پلي‌استر، الياف پلي‌پروپيلن، واكنش‌هاي هيدراتاسيون، دوام در محيط نمكي، ساختار اليافي تركيبي.

   Stabilization of clayey soils has long been one of the main challenges in geotechnical engineering, especially in areas where soils with expansive behavior or low resistance to repeated loading are observed. Kaolinite soil, as one of the important types of clayey soils, requires modification and improvement in order to be used in infrastructure projects due to its plate-like structure, high surface area to volume ratio, and limited reactivity. In recent years, in order to increase the durability, stability, and mechanical strength of soils, the use of mineral and chemical additives with pozzolanic properties and alkaline activators has been considered as a sustainable and effective approach. In this study, a combination of Portland cement, microsilica, sodium hydroxide (NaOH) solution, and sodium silicate (Na?SiO?) were used as the main stabilizers to improve the engineering behavior of kaolinite soil. The simultaneous combination of pozzolanic and alkaline materials leads to the formation of secondary reactive gels such as C-S-H, C-A-S-H and N-A-S-H in the soil structure, which play an important role in increasing the compressive strength, tensile strength and long-term stability. On the other hand, the use of alkaline solutions with different concentrations allows the investigation of the effect of geopolymer reactions and the kinetics of the formation of hydration products. Next, in order to evaluate the performance of the stabilizers, tests including unconfined compressive strength, Brazilian tensile strength, wet and dry cycle tests, and SEM and XRD microscopic analyses were carried out. The main goal is to achieve an optimal combination of stabilizing materials for effective improvement of kaolinite and provide a sustainable solution in stabilizing problematic soils for geotechnical applications, especially under variable environmental loading conditions. The results showed that using up to 12% stabilizer and replacing 50-65% of cement with microsilica and solutions of sodium hydroxide with a concentration of 8 M and sodium silicate with a concentration of 1% provide the highest resistance.

In this study, a simultaneous combination of three stabilizers—lime, silica fume (micro-silica) and a biopolymer—was employed to improve the geotechnical behaviour of swell-prone clay soils of bentonitic origin. This innovative combination was designed to achieve desirable mechanical properties, chemical stability in aggressive environments, swelling reduction and enhanced long-term durability of the specimens. Specimens were prepared with different stabilizer contents (2.5–15%), various lime–silica fume ratios, and incremental biopolymer dosages, and were evaluated after 7-day and 28-day curing periods.Laboratory tests comprised determination of Atterberg limits, modified compaction, unconfined compressive strength (UCS), free-swelling evaluation, durability tests in acidic, alkaline, saline and sulphate environments under wet–dry cycles, and microstructural analyses using XRD and SEM. The results indicated that lime addition initiated pozzolanic reactions, promoted release of Si and Al from the clay structure, and ultimately led to formation of cementitious phases such as C–S–H and C–A–H. The combination of lime and silica fume accelerated reactivity and produced additional C–S–H gels that played a key role in strengthening interparticle bonds. The biopolymer acted as a complementary agent by forming surface coatings on soil particles, thereby contributing to increased structural cohesion and volumetric stability.UCS results showed that mixtures containing 7.5% and 10% total stabilizer with a 60% lime : 40% silica fume ratio, or 50% : 50% (lime : silica fume), combined with 0.5% and 1% biopolymer, delivered the largest improvements in mechanical parameters and durability. Specimens stabilized with these 10% lime-based mixtures also exhibited acceptable durability in aggressive environments, whereas untreated soils experienced severe loss of strength and structural degradation. Replacing the biopolymer with zeolite in durability tests provided effective protection against ingress of deleterious ions.In conclusion, development of gel-like products from pozzolanic reactions, texture refinement, reduction of particle dispersion, and enhancement of structural integrity were the principal factors of improvement identified in this research. The proposed combined-stabilizer approach not only increased soil strength and durability but also enabled reduction in lime consumption and improvement of environmental sustainability.  

   In this thesis, a Wilkinson power divider is designed using a hybrid structure composed of three resonators—rectangular, square, and U-shaped—instead of the conventional quarter-wavelength transmission lines used in standard Wilkinson power dividers. The main objective of this thesis is to design a compact power divider with a wide bandwidth and improved S-parameters. This thesis consists of five chapters. Chapter one provides the fundamental concepts necessary for understanding the operation of power dividers. Chapter two reviews the concept of power division and examines common types of power divider structures along with their analysis. Chapter three presents a review of several designs that have been proposed in recent years. In chapter four, the proposed power divider is introduced and thoroughly analyzed from initial design to the final structure, including equivalent LC circuit modeling, even- and odd-mode analysis, and current density distribution. Finally, chapter five summarizes the key findings and conclusions of the research. Furthermore, this thesis introduces an innovative method to achieve multiple different center frequencies without altering the main structure. In this method, by placing three rectangular-shaped structures between the input and output ports and only changing their widths, different center frequencies can be obtained. After the design process, the characteristics and parameters of the power divider are as follows: The divider operates at a center frequency of 2.14 GHz and is capable of suppressing the second to eleventh harmonics with a suppression level of -21 dB. The physical dimensions of the divider are 10.743 mm × 10.243 mm, equivalent to 0.0095?g2 , representing an 81% size reduction compared to the conventional structure at the center frequency. The return loss is better than -51 dB, insertion loss is -3.087 dB, return loss at the output ports is better than -46 dB, and isolation between the output ports is better than -45 dB.

Given the increasing need for compact, high-performance passive devices with harmonic suppression capability in modern telecommunication systems, this thesis addresses the design of a compact Wilkinson power divider using modified resonator structures. The main objective is to reduce size, improve bandwidth, and effectively eliminate harmonics. The proposed design is implemented on a Rogers RT/duroid 5880 substrate with a thickness of 25 mil and operates at a center frequency of 2 GHz. Results demonstrate a significant size reduction of 86% compared to the conventional design, a wide fractional bandwidth of 65%, and effective suppression of 6 harmonics (2nd to 7th order). Electrical performance at 2 GHz includes return loss better than 26 dB, insertion loss approximately 3.031 dB, and isolation better than 20 dB. The total physical dimensions are only 0.078?g?×0.11?g?. This power divider, offering compact dimensions, wide bandwidth, and harmonic suppression capability, is considered an ideal option for modern high-density RF/microwave systems.

   Abstract In this thesis, an innovative compact dual-band branch-line coupler is designed, simulated, and analyzed to operate efficiently at 2.24 GHz and 5 GHz. The primary objective of the thesis is to develop a miniaturized and low-loss microwave coupler capable of effectively suppressing higher-order harmonics, tailored for modern wireless communication systems such as 5G and advanced Wi-Fi networks. To achieve this, modern design techniques have been employed, including the use of a modified interdigital capacitor, a rectangular-shaped resonator for dual-band performance, and a custom-designed harmonic suppression cell. The proposed structure was simulated using ADS 2023, and results show outstanding performance. In the first band (2.24 GHz), the coupler achieves a coupling level of S21?=?0.13 dB and a return loss of S11?=?24.02 dB. In the second band (5 GHz), these values are -0.21 dB and below -20 dB, respectively. The fractional bandwidth (FBW) is measured to be 46% in the first band and 20% in the second. One of the most significant achievements of this work is the suppression of harmonics up to the seventh order, alongside a remarkable reduction in physical size to just 0.0154?g2 . The circuit was fabricated on a Rogers 5880 substrate and tested at the Computational Intelligence Laboratory of Razi University, Kermanshah. The experimental measurements closely match the simulation results, confirming the stability and reliability of the design. Given its unique features, the proposed coupler is a strong candidate for integration into compact, multi-band, and next-generation RF systems. Keywords: Branch-line coupler, dual-band structure, modified interdigital capacitor, fractional bandwidth, microstrip lines, 5G systems

   The Wilkinson power divider is a key component in the design of RF and microwave circuits, used to split the input power into multiple outputs while maintaining impedance matching and high efficiency. The importance of designing a Wilkinson power divider lies in its ability to not only effectively divide power but also address the need for isolation between output ports and reduce return losses. These features make the Wilkinson power divider widely used in many communication, radar, and other RF applications that require precise and reliable performance. Proper design of this divider can lead to improved system efficiency and reduced signal interference across different frequencies.

  Diabetes mellitus is a chronic metabolic disease characterized by the body's inability to effectively use blood sugar or produce sufficient insulin to regulate it. If not properly diagnosed and treated, this disease can lead to serious complications such as heart disease, kidney damage, nerve disorders, and blindness. Given the increasing global prevalence of diabetes, early identification and prediction of this disease is of paramount importance. This research focuses on predicting the onset of diabetes using machine learning algorithms. For this purpose, the Pima Indian Diabetes dataset is employed, which includes features such as age, weight, blood pressure, fasting blood glucose levels, Body Mass Index (BMI), number of pregnancies, family history of diabetes, and other biological parameters. These data, extracted from a population of Native American women, are used to train and test various machine-learning models. In this study, different algorithms including Logistic Regression, XGBoost, AdaBoost, LightGBM, Decision Tree, CatBoost, and Gradient Boosting, were employed to predict the onset of diabetes. The results of this research, which compares different algorithms, particularly boosting algorithms, indicate that some of these algorithms demonstrate higher accuracy in predicting diabetes and can be used as effective tools for early detection and optimal management of the disease. The models achieved the following accuracy: Logistic Regression (0.92), XGBoost (0.96), AdaBoost (0.94), LightGBM (0.96), Gradient Boosting (0.91), and Decision Tree (0.91), with the best performance achieved by CatBoost with an accuracy of 0.98. Finally, suggestions for future research are offered.

   Cardiovascular diseases, particularly arrhythmias, have been among the leading causes of mortality in recent years. Consequently, the medical community has been actively seeking efficient and rapid methods for diagnosing these conditions. To enhance diagnostic speed and minimize potential human errors, the use of automated methods for detecting arrhythmias has gained significant attention. This study aims to achieve accurate and timely detection of various arrhythmias with minimal computational complexity and a reduced number of features. in this thesis, three types of arrhythmias—atrial, sinus, and ventricular—are analyzed, with each category comprising 100 ECG signal samples sourced from the SHEDB database. Two models, the Multilayer Perceptron (MLP) neural network and the Radial Basis Function (RBF) neural network, were employed for arrhythmia classification. Results indicate that the MLP model, achieving a test accuracy of 97.8%, significantly outperformed the RBF model, which achieved a test accuracy of 76.7%. These models were selected to reduce computational overhead compared to more complex models like Convolutional Neural Networks (C  ). furthermore, various temporal, statistical, and frequency domain features were examined during the feature extraction process. The best performance was achieved using eight selected features: Root Mean Square (RMS), Waveform Length (WL), Absolute Sum of Squares( ASS), Mean (MEAN), Skewness (SKW), Kurtosis (KUR), Dominant Frequency (DF), and Amplitude of Dominant Frequency (AFDF).

 Brain tumors are caused by abnormal cell growth in the brain. Magnetic resonance imaging (MRI) is the most widely used method for diagnosing brain tumors. Through these MRIs, doctors analyze and identify abnormal tissue growth and can confirm whether the brain is affected by a tumor or not. Today, with the advent of artificial intelligence techniques, the diagnosis of brain tumors is performed using machine learning techniques and algorithms and artificial neural networks. The advantages of using these algorithms include rapid prediction of brain tumors, fewer errors, and greater accuracy, which helps in decision-making and choosing the most appropriate treatment for patients. In this study, an artificial neural network will be used to detect the presence of a brain tumor and its performance will be analyzed. The main goal of this research is to design an artificial neural network-based system for automatic detection of brain tumors from MRI images and classify MRI images into two categories: "brain tumor" and "normal" and ultimately achieve high diagnostic accuracy in MRI images. Keywords: Brain tumor detection, Artificial neural networks (ANN), MRI images, Convolutional neural network (CNN).

   A novel design for realizing optical 2-bit analog to digital converter based on two-dimensional photonic crystals will be proposed in this thesis. The proposed structure consists of two main parts; a nonlinear 3-channel demultiplexer, followed by an optical coder. The nonlinear demultiplexer quantizes the input analogue signal based on its optical intensity at the central wavelength of ?=1550 nm and  consists of two ring resonators using nonlinear rods inside. For appropriate values of the input optical intensity, one of the ring resonators can drop the optical signal at its corresponding output port using Kerr effect. The optical coder also contains two similar ring resonators which can converts the quantized levels to 2-bit binary code. The base structure is a square lattice of silicon dielectric rods with refractive index of 3.46 implemented in an air background. The nonlinear rods used in the ring resonators are made of doped glass with refractive index and nonlinear Kerr coefficient of 1.4 and 10-14 m2W   respectively, and the total footprint of the structure is about 555 ?m2.   Maximum sampling rate is up to 240 GS/s .

Abstract SOI (Silicon-on-Insulator) field effect transistor is a transistor with many advantages over conventional silicon transistors, which is an advanced technology used in semiconductor transistors, here it is SOI-MESF transistor. The effect of the metal-semiconductor field is discussed. Using two metals (platinum) in SIO2 and one piece of oxide in the SI transistor improves DC WRF characteristics, increases breakdown voltage, increases cutoff frequency, improves potential, and improves current. . In particular, the changes made in the SOI-MESFET structure significantly improve the performance of these transistors. SOI-MESFET is very suitable for high-frequency and high-power applications, SOI-MESFET transistors are used in applications due to their special characteristics. Some of these applications include:    • High-frequency circuits: due to the reduction of interference capacitance, these transistors are suitable for high-frequency and microwave circuits. • RF amplifiers: due to thermal stability and optimal performance at high temperatures, they are used in radio frequency (RF) amplifiers. • High power circuits: due to high breakdown voltage and reduction of self-heating forces, they are used in high power circuits. • Applications: Due to the mentioned military features, they are also used in military and aerospace equipment. • Integrated circuits: due to low power consumption and high stability, it is used in integrated circuits and systems on a chip.

   This thesis presents the investigation, design, simulation, and fabrication of a compact Gysel power divider with a hybrid structure and wide pa  and. The primary objective of this research is to enhance the performance and reduce the size of the Gysel power divider by employing novel resonators and lumped elements. Rectangular and hairpin resonators were designed to create transmission zeros and improve impedance matching. These resonators are capable of generating six transmission zeros in their stopband, significantly improving filtering performance and unwanted frequency suppression. The circuit implementation utilized a substrate with the specifications of Rogers RT/Duroid 5880. The initial simulations of this circuit were conducted using the Advanced Design System (ADS) software. Simulation results indicated that the designed circuit exhibits very low return loss (S11) and adequate power transmission (S21) at the frequencies of 8.74 GHz and 9.23 GHz. Specifically, at these frequencies, S21 was measured to be -3.08 dB and -3.1 dB, respectively, while the return loss (S11) was -22.3 dB and -20.8 dB, respectively. Furthermore, the isolation (S32) was found to be less than -25 dB, demonstrating good signal separation between ports. These simulation and measurement results show good agreement and confirm the optimal performance of the circuit. Following the simulation phase, the designed Gysel power divider was practically fabricated and tested. The fabrication process included preparing the printed circuit board (PCB) mask, exposing and etching the board, and soldering the lumped elements. The practical measurement results closely matched the simulation results, validating the circuit's optimal performance in real-world conditions. One significant achievement of this research is the reduction of the circuit's size by 86% compared to the initial structure, highlighting a considerable advancement in circuit design and optimization. This dual-band power divider, with its optimized design and compact size, is suitable for various telecommunications, radar, and electronic systems that require precise and efficient power division. Recommendations for future work include further optimization of the pa  and width, the use of new materials with better dielectric properties, and examining the environmental and thermal effects on the circuit's performance. These advancements can further develop and enhance the technology of power dividers, improving the efficiency of telecommunications and radar systems. Given the results obtained, it is anticipated that these optimization and design methods will continue to be of interest and lead to further improvements in telecommunications and electronic equipment. This research offers an innovative and efficient solution, marking a significant step forward in developing advanced technologies in the field of telecommunications and electronics.

  سيستم هاي ميكروالكترومكانيكي يا به اختصار ممز[1]) (MEMS، كارايي قابل توجهي در فركانس هاي مايكروويوو راديويي (RF) دارند . اين تكنولوژي كاربردهاي MEMS (سيستم هاي ميكرو الكترومكانيكي) را به خصوص در سيستم هاي مخابراتي بيسيم و ماهواره نشان مي دهد. در واقع سوييچ هاي ممز   RF، ميكروماشين هاي سطحي هستندكه از حركت مكانيكي براي ايجاد يك"اتصال كوتاه" يا " مدار باز " در خط انتقال RF استفاده مي كنند .اين سوييچ ها با استفاده از روش هاي ميكروالكترومكانيكي و با اتصال الكتريكي–فلزي و با استفاده از فواصل هوايي ساخته مي شو ند . در طراحي و ساخت سوييچ هاي ممز، دو نوع اتصال مختلف وجود دارد. اين اتصال شامل پيكربندي خازني (يا شنت) و نوع فلز به فلز (يا سري) مي باشد .در سوييچ هاي خازني به دليل وجود لايه دي الكتريك بين خط انتقال و پل ، چه در حالت بالا(مدار باز) و چه در حالت پايين(مدار بسته) بين پل و خط انتقال هيچ اتصالي وجود نخواهد داشت . به دليل وجود اين فاصله سوييچ در حالت بالا و در حالت پايين مانند يك خازن عمل مي كند كه با افزايش نسبت خازني ، سوييچ عملكرد فركانس بالاي بهتري خواهد داشت. در روش پيشنهادي يك سوييچ خازني با يك لايه پلي سيليكان و يك دي الكتريك از جنس هوا و مواد ديگر كه بر بستري از سيليكان و يا خطوط CPW قرار ميگيرند ، بررسي مي شود و سعي ميشود ولتاژ تحريك سوييچ را كاهش داد چرا كه يكي از مهم ترين پارامتر ها در طراحي و ساخت سوييچ هاي ممز، ولتاژ تحريك مي باشد كه در واقع پايين ترين ولتاژي است كه با اعمال آن به مدار، سوييچ در حالت روشن قرار ميگيرد و اساسا كوچك بودن اين مقدار ولتاژ براي ما مطلوب است اما از آنجاكه اين پارامتر با پارامتر زمان سوييچينگ نسبت عكس دارد، نميتوان آن را به ميزان زياد كاهش داد. لذا با روش هاي ديگري مانند كاهش يا افزايش فواصل هوايي و تغيير جنس ماده ي دي الكتريك ، به بهبود پارامترهاي مهم سوييچ ، مانند زمان سوييچينگ و عملكرد فركانس بالا مي پردازيم

  Vibrationenergy harvesting is an ideal source of renewable energy, in this thesis a newmicro-electromagnetic harvesting mechanism for low-power applications isintroduced that can be used at a vibration frequency of less than 11 Hz, whichis used for motion harvesting. Fits humans, moving vehicles, and structuressuch as buildings, bridges, and streets. The energy harvesting mechanismresulting from the moving electromagnetic field (magnet) in the vicinity of afixed coil made of material (copper) induces a current in the coil, examples ofdifferent energy harvesting geometries to achieve the best and lowest frequencyand harvesting performance The energy generator is specified in terms ofdimensions, output power, stable sinusoidal voltage. As far as the builtprototypes showed the ability to harvest energy at low frequencies in the rangeof 2 to 10 Hz, with a voltage between 330 and 800 mV, and an output power of upto 2800 µW.

  In recent decades, the discussion regarding human activities in protecting or destroying the environment and preventing the phenomenon of global warming has caused the attention of scientists to be drawn towards technologies that are in this direction. Semi-warm asphalt is a technology that reduces the use of fossil fuels and the production of greenhouse gases by reducing the mixing temperature. It is also possible to protect the environment and reduce its pollution by reusing the wastes of other industries and recycled materials, while saving costs, by reducing industrial waste. Many studies have been conducted in the world to prevent the premature failure of the pavement system caused by moisture. In these studies, different materials were used to improve the functional properties of asphalt, and these materials can be used as bitumen additives or aggregate additives. Sometimes even some of these materials are added directly to the mixture being produced.In this research, it is focused on improving asphalt properties. Nowadays, due to the increase in the amount of traffic and the number of axles, the use of additives in asphalt concrete has become common. An effective additive in increasing the bearing capacity and improving the tensile strength of asphalt mixtures is the use of fibers. Fibers mainly contribute to the reinforcement of asphalt mixtures.Asphalt mixtures use fibers. Fibers mainly contribute to the reinforcement of asphalt mixtures.The results obtained from the Marshall resistance test showed that the addition of 0.3% of carpet fibers and 0.9% of 5-component fibers has the best results among the research samples. Also, the Marshall resistance value obtained for 5-component fibers is much higher than carpet fibers. According to the results of humidity sensitivity test and TSR parameter, it can be said that carpet fibers improve humidity sensitivity up to 0.6%. 5-component fibers also increase humidity sensitivity up to 0.9. According to the tensile modulus test, the use of 5-component fibers significantly increases the tensile modulus. The carpet fiber also increases up to 0.6% and after that it takes a steady and uniform trend. The results of the dynamic creep test showed that the use of more than 0.3% of carpet fibers reduces the dynamic creep and mental number. For 5-component fibers, due to the dissolution of the    part in the mixture, we have seen the growth of the mental number up to 0.9% of the fibers. The results of the indirect tensile test in wet and dry states showed that the addition of 5-component fibers increases the tensile strength in wet and dry conditions. Also, the addition of carpet fibers in the dry state increases tensile strength in all investigated percentages, but the indirect tensile strength increases up to 0.6 percent of carpet fibers and decreases from 0.6 to 0.9.

  In

   Due to the growth of the use of electronic devices such as electronic amplifiers, wireless devices, etc., power dividers have gained special importance, and the most important of these dividers are Wilkinson and Gysel, which are widely used. take The main task of dividers in the electronic circuit is power division, which is evaluated in symmetrical and asymmetrical divider models today.    The problem discussed in this thesis is to pay attention to the reduction of the physical size that affects the size of the electric circuit, that the reduction of the designed dividers reduces the dimensions of the circuit. It increases the quality of the output wave and also increases the conduction bandwidth, which plays a significant role in the selection of dividers in devices, which is investigated using microstrip technology today. In this thesis, ADS software has been used to simulate a Gysel divider, which has been obtained by reducing the dimensions, removing additional harmonics, and providing proper isolation, and good results have been obtained.

  Abstract:Today, due to the reduction in the size of electronic and telecommunicationcircuits and boards and the increasing use of circuits with high speed andaccuracy, the frequency spectrum known as microwave is widely used. Amongthese, one of the most widely used elements In high frequency and radiocircuits, they are power dividers and combiners (couplers). Among theapplications of power dividers, it can be mentioned that they are used insatellite receivers, antennas, power amplifiers, communication and radiosystems, etc., during which these inactive circuits, they divide or combine thepower of signals in radio frequencies.There are various types of power divider circuits, among the mostreliable ones, we can mention the Wilkinson, Gysel, T-shaped power dividers,etc., which are used in different equipment depending on the efficiency. In themeantime, Gysel power divider is more popular than other dividers due to itsmany applications and having advantages such as suitable thermal conductivitycompared to Wilkinson, high bandwidth, optimal matching and high isolation betweenoutput ports. Gysel power amplifiers can be referred to isolation of outputports, input and output impedance matching and their flat structure. Nowadays,many Gysel power dividers have been designed. In this thesis, a new structureof Gysel power divider has been proposed using microstrip lines, and also inthis thesis, in order to remove unwanted harmonics, by placing modifiedresonators with a new structure of quarter-wavelength lines is presented. Thedimensions of the resonators were determined using the PSO optimizationalgorithm, and the results show that the designed power divider has a returnloss of less than -20 dB, an appropriate insertion loss of 3.09 dB, a compactsize of 0.14 ?g × 0.42 ?g , and a high bandwidth of FBW=125%.  

  In recent years, the electrothermal effect has beenwidely investigated in microfluidics and has been proposed and used as a promising technique for use in laboratory devices on a chip. In this research, firstly, a variety of electrokinetic phenomena   briefly introduced , which includes electroosmotic, electrothermal and electrophoresis. At first, we simulated electroosmotic micropumps in two symmetric and asymmetric geometries and showed that in fluids with High conductivity   electroosmotic EO phenomenon is inefficient, and in the following, we have investigated and compared the electrothermal micropump, which is suitable for such fluids, in two symmetric and asymmetric geometries, without external thermal bias and also under the external thermal bias. To strengthen the pumping flow, a micropump with a new geometry has been designed and simulated with rectangular holes where the electrodes are located on the inner surface of the holes, and the result of the design was that the output velocity in the presented design has increased significantly compared to the previous conventional designs. Finally, the effect of the electrical conductivity of the fluid, applied frequency, electrical potential, length of the microchannel, length of the wide electrode, the depth of the holes and the gap between the two electrodes were investigated on the fluid velocity and the maximum temperature created in the microchannel

The current research is to present a new model for low noise amplifier design in wireless local area networks. For this purpose, we consider a low noise amplifier with cascode technique and then modify the cascade. The results of this study show that the modified cascade stage has high gain and optimal noise figure. The LNA will be designed to be stable in the 3.1 to 10.6 GHz range. The results of this study can be widely used in medical devices. The results of this research showed that the amount of noise in the designed circuit has been reduced by 45.57%. Also, the amount of gain in the circuit designed by the author has also increased by 20.5%. Therefore, it can be said that in the current research, satisfactory results have been obtained regarding reducing noise and increasing gain.   

A microelectromechanical switch is an electronic device that disconnects or connects electric current by changing the position or shape of its microscopic structure. These switches consist of micro and even nanometer structures and are used as an alternative to conventional electromagnetic switches in electronic devices. With the change the dimensions, the characteristics of the switch change. For example, by reducing, the response time is improved, as well as an increase in sensitivity to electric current occurs. Also, with the change, the application frequency was higher. Microelectromechanical switches are used in many electronic applications, including memories, sensors, electronic chips, and communication devices. It is also used in the automotive, medical and industry. In this thesis, the basic structure of switches based on micro-electromechanical systems for use in radio frequency has been investigated and analyzed, and the design challenges of different analyzes have been investigated in the analysis. Then, by evaluating the previous switches and previous examples, their results and the weak and strong points of each have been analyzed. Finally, a new microelectromechanical switch for high frequency applications has been designed and simulated using polysilicon material. The presented structure is operated with 5V voltage and its switching time is less than 38 microseconds. COMSOL version 6.1 software is used to simulate the proposed structure. One of the most prominent features of the provided switches is its size, which is only 60?m × 220?m, and this value is much smaller compared to other articles and designed switches. Also, one of the other terms in the design of high frequency switches is the value of capacitor at the time of the switch, or in other words, high capacitor and low capacitor, which is referred to as the capacitor ratio. This parameter for the presented switch is 65, which is very ideal and provides various applications for the switch. At the end, the presented switch structure has been modified and with the help of twisted anchors and different structures, different switches have been presented under the title of the first and second modified structure. Each of these structures moves with the same voltage of 5 volts, and for each of these structures, the structures of switching time, capacitance ratio, displacement, and the effect of contact force have been simulated and analyzed at the level of the switch. Also, the type of material in the function of the switch has been investigated and by changing the material to gallium arsenide, it is found that the contact forces on the surface of the switch are much less and the switching time increases.   

   In recent decades, due to the growth and development of mobile telecommunication equipment and portable systems, RF researchers and designers have focused more on designing circuits with low voltage and power consumption. Most systems are now wireless, and reducing power consumption is important, which can lead to increased battery life. One of the important parts in receiver systems is the low-noise amplifier, which should be designed with low power. In this thesis, a narrowband low noise amplifier with low energy consumption and high voltage gain is presented using 0.18 ?m RF CMOS technology, so that in the proposed amplifier, the threshold voltage of the transistor can be reduced from the bias technique. body and to reduce the supply voltage and current, current reuse technique has been used. Due to the use of noise removal technique in the proposed circuit, it has resulted in acceptable noise reduction, and with the appropriate selection of circuit elements, a compromise between circuit parameters has been created. The results of the investigations show that the gain of the proposed low-noise amplifier is 13.8 dB, S11 is less than -14.37 dB, and the noise figure is 2 dB at the central frequency of 2.4 GHz. Also, the linearity is -2.5 dBm and the power consumption at the power supply voltage of 1 V is 3.79 milliwatts. The use of such a circuit can greatly contribute to the design of low-power, high-performance wireless communication systems. With further modifications, it can also be used in IoT applications where low power consumption is critical. Overall, this work shows a promising trend for the development of compact, low-power and efficient amplifiers using advanced RF CMOS technologies.

Today, SOI-MESFET transistors have many applications in the electronic world and due to their advantages such as high switching speed and working at high voltage and frequencies and reducing power consumption compared to BULK silicon body technology, but with this advantage There are also some limitations, such as the effect of self-heating and the effect of body buoyancy. In this research, we introduce a new silicon-on-insulator structure, which compared to the conventional structure, has advantages such as higher breakdown voltage, higher drain current, and improvement in RF parameters. In this structure, we have used an oxide region in the channel region. The oxide region is located between the gate and the drain, which causes an increase in the breakdown voltage, and the reason for this is that the breakdown tolerance of the oxide is higher than that of the semiconductor. A metal region is buried inside the oxide region. The metal region improves RF parameters and prevents electric field congestion. In this structure, the breakdown voltage is around 22 volts, compared to the basic structure, which is about 19 volts, we can see an increase of 3 volts, and also the drain current has increased compared to the basic structure, and the RF parameters have all improved, and as a result This structure is ordered to work in high power applications. This research is about a completely new structure that has excellent efficiency for working at very high powers. In this structure, by using an oxide region in the channel, it improves the breakdown voltage from 19 volts in the basic structure to 22 volts. We are new in the structure, and on the other hand, by using nickel and SI3N4 areas, we have improved the ac parameters and increased the maximum transmission power from 0.9 W/mm in the basic structure to 0.998 W/mm in the new structure, so we can safely say that It is an excellent structure for working at high powers  

Microstrip lines are good candidates for designing microwave filters, power amplifiers, inventors. With other elements of microwave circuits on a circuit board, he pointed out. Other applications of microstrip lines include waveguides, oscillators, and microwave power dividers.  

  In this dissertation, the designs of antennas with two bands and two polarizations have been studied. In this study, three different and new designs in the field of multiple antennas are presented. The simulations for all three antennas were examined in ansys hfss software and the antennas were evaluated and compared with each other.The structure of the designed antennas consists of an FR4 substrate and two or four 50 ohm power lines and an improved DGS (incomplete ground plate). The first proposed structure is a square antenna with dual patch. In Figure 4-10, this antenna is made using FR4 substrate with a thickness of less than 1 mm and a dielectric constant of 4.4 and a loss tangent of 0.022, and the overall dimensions of the substrate are 32 × 32 mm2. This structure is powered by a 50 ohm microstrip power line. According to the theory, patch antennas are located at the bottom of the substrate, the defective ground plate or DGS, and at the top of the substrate, the radiation patch and the microstrip power line. Where the measured bandwidth was 4.2 GHz equal to 2.86 GHz (3.59-6.53 GHz). And the measured bandwidth is 9 GHz equal to 3.08 GHz (7.05 - 10.13 GHz).For the second simulation, by creating a circular patch with a thickness of 10 mm, a suitable and practical bandwidth can be obtained from the antenna. At 3.5 GHz, the impedance bandwidth is approximately equal to 2.7 GHz, and at 10 GHz, the impedance bandwidth is equal to 4 GHz, which is It is considered a desirable band.To design the third design in the final antenna structure shown in Figure (32-4), the structure has an impedance bandwidth of 5.076 (3.5030 - 8.5790) GHz and 4.935 (11.587 - 16.522) GHz. The proposed antenna configuration creates a circular polarization with a phase difference of 90 degrees, which has many applications in the industry.

Nowadays, people all around the world are suffering from many problems and diseases, one of the most important of that in recent years is covid-19, which causes many social, economy and other harms to human society. Therefore, treatment of this disease is one of the priorities of human beings today to return to normal living condition. One of the most significant steps and backgrounds for treatment of this disease and other similar diseases is nothing but diagnose this disease in accurate and fast methods that are useful for providing the ground for treatment, increasing knowledge about of that and preventing from spreading new strains. There are many different kinds of ways to diagnose this disease, which one of the most accurate and best is imaging and scan the lung and analyze it. On the other hand, artificial neural networks have many applications such as, processing and analyzing various data based on existing data sets from numbers to images, etc. one of these types of networks, is called convolutional neural networks, which are specifically used for analyzing, classification and processing various images. In this research, our goal is processing lung scan images by convolutional neural networks and receive the results in the output. Our results appear in the output according to predefined classifications based on the primary data sets, which include conid-19, normal and pneumonia. We can benefit from these results to diagnose and combat this disease. Because of the attractiveness and practicality of this field, before the present research, various researches have been done in this field. One of most important goals of this research is improve and optimize the convolutional networks by utilizing meta- heuristic algorithms in order to reduce the layers and network connections for easier and more cost-effective implementation while maintaining network speed and accuracy.

چكيده مقدمه: يكي از شاخههاي مهندسي برق، الكترونيك، و يكي از شاخههاي الكترونيك، مدار مجتمع فركانس راديويي است، كه سوئيچ يكي از المانهاي آن محسوب ميشود. چنين سوئيچي اغلب با استفاده از ترانزيستور ياديود ساخته ميشود،[2],[3 [اما در دهههاي اخير تكنولوژي سيستمهاي ميكروالكترومكانيكي توجه محققين اينحوزه را به خود جلب نموده است،[3]–[7 [اما با توجه به آن كه طراحي آن بسيار چالشبرانگيز است، تاكنونبصورت گستردهوارد صنعت نشده است. هدف: چالش فوق الذكر به اين صورت است كه هرگاه طراح يكي از پاسخ هاي سوئيچ را به مقدار مطلوبي مي رساند، مطلوبيت دست كم يك پاسخ ديگررا ازدست مي دهد، بنابراين نگارنده كوشيده است روشي را ارائه كندكه بطور بهينه طراحي مورد نظر را به انجامرساند. روششناسي پژوهش:درابتدا سهقانون مهم حاكم بررفتار سوئيچ موردنظربا استفاده ازرياضيات وبطوردقيقتعيين گرديده است. اين قوانين به خصوصيات سوئيچ بستگي دارند. سپس با استفاده از يك برنامة كامپيوتري درمحيط نرمافزار متلب، اين خصوصيات بگونهاي تعيين گرديده اند كه بازاي آنها قوانين مذكورمنجربهپاسخهاييگردند كه مطلوب ما باشند. سپس نگارنده به منظور اطمينان بيشتر، دو عدد از سه پاسخ بهدستآمدة سوئيچ را اينبار با استفاده از نرمافزار كامسول به دست آورده است. در نهايت پاسخها با پاسخهاي تعدادي از سوئيچهاي ديگركه در مقالات اين حوزه آمده مقايسه شده اند. يافتهها و نتيجهگيري: محققين اين حوزه اغلب با استفاده از آزمون و خطاي انساني تلاش مي كنند تا بر چالشفوق الذكر غلبه نمايند، درحاليكه ميتوان با استفاده از روشهايي مبتني بر رياضيات يا محاسبات، طراحي موردنظر را بطور بهينه به انجام رساند. پيشنهاد نگارنده استفاده ازتركيب الگوريتم ژنتيك با يكي ازتكنيك هاي تحليلتصميم چندمعياره بوده است. استفاده از چنين روش هايي چه به لحاظ كمي و چه كيفي سبب بهبود طراحي مي- گردد.  

  Electromyography (EMG) is a widely used diagnostic tool in clinical physiology which is used by physicians to accurately diagnose neuromuscular disorders in patients, particularly myopathy. In this research, continuous wavelet transform method and convolutional neural network were used to diagnose myopathy from EMG signals. The data analyzed in this study included two groups of healthy (20 signals) and myopathy (44 signals). The continuous wavelet transform was performed to decompose each signal after preprocessing operations on them. Then the scalogram was extracted and used as an input image to the convolutional neural network. The neural network structure used in this research composed seven layers which were taught by 70% of the total data. The final accuracy of this model in detecting myopathy from EMG signal was 89.06%.

Design and fabrication of Wilkinson power divider with harmonics suppression using symmetrical rectangular resonator  

   Abstract: this paper presents a technique for low noise figure reduction of low-noise-amplifier. The proposed LNA is designed in a current reuse technique that offers lower noise figure. Also, using inductor as a gate inductor reduces the effect of the input parasitic capacitance on the noise figure and provides a good matching at the input and output of the LNA. It shows that the proposed technique reduces significantly the noise figure and improves the matching. The proposed LNA is designed in 0.18 ?m process with 1.5 V supply voltage and simulated cadence software. The simulation results show that The LNA achieves voltage gain of 13.3 dB, noise figure of 2.3 dB, and S11 less than ?10 dB, while consuming only 8.1   mW. The layout schematic occupies 0.812 of chip area.

در اين پايان نامه، يك تقسيم كننده توان ويلكينسون ارائه شده است. كه در ان علاوه بر دارا بودن دو باند كاري داراي حذف هارمونيك نيز مي باشد. اين تقسيم كننده با كمك رزناتتورهاي متقارن و استاب هاي بلند و كوتاه طراحي شده است.اولين فركانس كاري اين (WPD) در فركانس 2GHz مي باشد و دومين فركانس كاري 14/1GHz مي باشد و اندازه اين كار   مي باشد لازم به ذكر است كه حذف هارمونيك و تقسيم كننده بسيار مهم است كه در اين تقسيم كننده 5 هارمونيك حذف شده است.اين تقسيم كننده بر روي برد RT-5880 ساخته و اندازه گيري شده است جواب ساخت و شبيه سازي تطبيق مناسبي دارند.

Abstract In recent years, microfluidic technology has been considered by many researchers in various fields of biology, chemistry and medical engineering due to its many advantages such as reducing the sample size, producing less waste, saving time and money. One of the main parts of laboratory processes is cell isolation. In laboratories, different methods are used to isolate or count cells; One of the main disadvantages of these methods is the high volume of the prototype, and the process of testing by these methods requires a lot of time and money. The use of dielectric force has become one of the most popular manipulation methods in microsystems due to its favorable effects such as laboratory scale, simplicity of instrument, ability to induce positive and negative forces and, most importantly, ineffective particle structure. Today, with technologies such as on-chip laboratories and dimensional shrinkage (nano and micro), all of these experiments can be performed in less time, with greater accuracy, and with smaller sample sizes. With the development of on-chip laboratory technology, the tendency to use this technology for cell isolation for cell counting or diagnostic applications in micro-dimensions has increased. Since the electrophoresis force allows us to use laboratory technologies on the chip to count or separate, and has the ability to shrink in micro and nano dimensions, more attention has been paid. What is discussed in this dissertation is the effect of different electrode shapes, different frequencies, fluid properties, channel dimensions, electrode dimensions and electrode spacing in applying dielectric force in cell separation. Since the main purpose is to isolate biological cells and these cells are strongly dependent on temperature, after comparing electric fields, field gradient, fluid conductivity and dielectric force, the effect of changes in these elements on temperature should be investigated. The sensitivity of biological cells to temperature is such that if the temperature rises above a certain value, these cells will die. Then the effect of changes in voltage and fluid conductivity is investigated and finally its effect on the process of separation of living cells from non-living cells.

چكيده مغز انسان پيچيده ترين سيستم هستي است كه از ويژگي هاي منحصر به فردي برخوردار است. طي چند دهه اخير ، پژوهشگران سعي داشته اند تا با الهام گرفتن از مغز و نحوه عملكرد آن در پردازش اطلاعات ، سيستم هايي مشابه آن ايجاد كنند . يكي از ويژگي هاي مهم مغز توانايي خود تعميري و قابليت تحمل خطاست ؛ به طوري كه در صورت‌ آسيب ديدن چند سيناپس ، به دليل وجود سلول هايي به نام آستروسيت و از طريق سيناپس هاي سالم باقي مانده ،   سيستم عملكرد خود را در حد قابل قبولي حفظ مي كند . از آن جا كه سلول هاي عصبي در محيطي تصادفي فعاليت مي كنند ، وجود نويز يك مسئله غير قابل اجتناب است . به همين دليل در اين پروژه براي اولين بار به بررسي تاثير نويز در شبكه آستروسيت – نورون خود تعمير پرداخته شده است . با وجود اعمال نويز به جريان نورون ها ، سيستم هم چنان از توانايي خود تعميري برخوردار است و از طريق فيدبك غير مستقيم از سلول آستروسيت اثرات مخرب سيناپس هاي آسيب ديده را تا حدودي جبران مي كند . نتايج نشان مي دهند كه با وجود حضور نويز در جريان نورون ها و اعمال 80 درصد خطا به شبكه ، سلول آستروسيت هم چنان سعي در جبران خطا دارد و تا حد امكان فركانس هدف را حفظ مي نمايد .   

Abstract: The study of neural systems has been of great interest to scientists around the world in recent years, as scientists in various sciences, including biology, neurophysiology and engineering, have tried to study, understand and characterize neural networks. In this regard, neuromorphic scientists and engineers, along with neurobiologists, have simulated and implemented different parts of the nervous system, such as neurons, through analog and digital circuits. Understanding and imitating the natural state of neuronal communication can lead to further advances in the treatment of neurological diseases and injuries. A neuromorphic circuit that implements neurons electronically can reproduce the behaviors observed in real neurons using electronic circuits. The more the operation of these circuits is similar to the operation of a real neuron, the more efficient the circuit. In most of these designs, the effect of noise, which has always existed in electronic circuits, is ignored. Noise is one of the sources of changes in the function of the nervous system that affects all aspects of the functioning of the nervous system. Therefore, it is very important to know the types of noise and its sources in the nervous system and to study its effect on the structure and function of the brain and neurons. In this dissertation, our aim is to investigate the effects of noise on the output of the analog circuit of the Izhikovich neuron model. Using MATLAB software, the mathematical equations of the used neural model are implemented and the output of the model is simulated in this software. We will also simulate the orbital part of this research using Hspice software and examine the effects of noise on the circuit output. Finally, the output of MATLAB software and the output of the simulated analog circuit in Hspice software are compared. Keywords: Neuromorphic, Neuron, Spike, Noise, Izhikevich neuron model.

In this thesis, a new structure WPD with a combination of trapezoidal, circular and rectangular resonators is presented, which has small dimensions of about 11.66 mm× 13.9 mm (0.1 ?g × 0.08 ?g). It also rejects unwanted harmonics from 3.2 to 17 GHz, which means up to 10fo. The operation frequency is located at 1.67 GHz. Other benefits of proposed PD include good FBW (138%) and return losses (-28 dB). Also, the even and odd-mode analysis with LC equivalent circuit and ABCD matrix has been employed to assess the behaviour of the proposed WPD. There is a good agreement between measurements and simulation results. Thus, the proposed Wilkinson power divider can be utilized in various microwave circuits and systems.  

  Design, simulation and fabrication of Wilkinson Power Divider with compact size and improvement parameters Thesis Title:

 B

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طراحي مدارات ديجيتالي ممريستوري براي محاسبات درون حافظه اي

  SRM motors have attracted considerable attention due to its low cost and robust structure, high efficiency, and the ability to track at variable and high speed and high ambient temperature. SRM engines are one of the oldest types of electric motors that were left out of the lack because of proper control systems, but today with modern semiconductor technology, SRM engines can be made cheap and even easier than induction motors, and will Compete with all other electric motors soon. One of the problems with this machine is the speed control complexity that is influenced by the effect of the voltage thresholds of each phase and the detection pulses which applied on phases but nowadays engineers are working to overcome the obstacles that cause these problems over time.

SRM motors have attracted considerable attention due to its low cost and robust structure, high efficiency, and the ability to track at variable and high speed and high ambient temperature. SRM engines are one of the oldest types of electric motors that were left out of the lack because of proper control systems, but today with modern semiconductor technology, SRM engines can be made cheap and even easier than induction motors, and will Compete with all other electric motors soon. using the sensor to detect the position of the rotor increases the price and complexity of the engine structure, and in addition, in the event of burning or dusting and the mass of each sensor and also noise on sensor cables which given the fact that it is used in industrial environments or electrical appliances, It is likely that this engine will not be welcomed, but in a sensorless method that uses feedback from different parts of the engine and using a microprocessor and writing complex codes to detect the position of the rotor and start the engine and take a long time It takes itself and needs much more science, but all of these happen just one time, and the engine's surroundings make it easier to control other engine parameters.

Today, the use of wireless technology has become very popular It has become an indelible part of everyday life and even the industry And an example of its applications can be cell phones, WiFi networks, Radio digital information exchange and more Cited.   To achieve these technologies, various engineering knowledge and achievements, especially in the field of electronic, have been used. Providing these features on a small chip in the advancement of the science of minimizing components VLSI , CMOS technology And the construction of RF components and circuits It's possible; RF design includes parts such as antennas, low noise amplifiers,mixers, oscillators, phase lock loops, frequency instruments and power amplifiers.An important part of the network after the antenna is the low noise amplifier, which has various parameters that interact with each other. Including noise, bandwidth, linearity, input matching and extra ; We have tried to get a more linear response from the circuit using the Linearity enhancement techniques and we have achieved 3.1-10.6 GHz bandwidth. The proposed circuit structure in the fourth chapter of this thesis is examined.key words:Low noise amplifier, bandwidth, linearity, gain, linearization technique

In this thesis design and fabrication of real time powersystem emulator for power transformer study was presented. Real time powersystem emulator historical studying and review on this emulator advantages inpower system analysis and scenario of hardware in the loop examining clearlyshow the subject importance. Many efforts have been devoted in this field andtodays trends in Field Programmable Gate Array(FPGA) utilization for itsendless advantages was increasingly reported in IEEE literatures and industrialapplications. A. Benigni and A. Monti in a paper named A Parallel Approach to Real Time Simulation of PowerElectronics System (2015)

Design Of Ultra Wideband Low Noise Amplifier (LNA) With Current Reuse And Noise Cancelling Technique

طراحي تقويت كننده كم نويز در باند فركانسي فوق وسيع با استفاده از تكنيك استفاده مجدد جريان مكمل اصلاح شده

  Over the past several years, different control methods have been presented to avoid hyper synchronization of neurons in various papers, Because this abnormal synchrony disturbs the function of the brain and causes the diseases Like epilepsy and Parkinson. The primary treatment of disease   is drug therapy. if drug   treatment is unsuccessful, other therapies are there such as surgery and stimulation of the damaged area. in the surgical procedure, the damaged area of the brain is destroyed , which will have many side effects. In the direct stimulation technique, due to permanent stimulation of the damaged area, surgical problems can be reversed. Since stimulating methods of feedback and non- feedback are mathematical equations and have no biological background,   tried to use astrocytic stimulant as a biological stimulant. Several studies have shown that the effect of astrocytes on the absorption or release of glutamate in the synaptic space, the storage of potassium ion, and the regulation of extracellular pH is necessary to maintain the correct level of irritability in the CNS. The impairment of this function can lead to an increase in the stimulation of the neurons and their synchronization with each other. The disorder of this function can lead to an increase in the stimulation of the neurons and their synchronization with another. Therefore, astrocytes can apply appropriate control feedback to regulate neuronal activity. In this study, we tried to investigate the biological stimulus ability   induced by the behavioral dynamics of astrocytes using analog circuit design. Because astrocytes play a major role in neurological interactions in the neurons synchronization and desynchronization , the above stimulant advantage can be considered as the biological basis based on the interaction between neurons and astrocytes. To simulate the behavior of neurons in diseases caused by super-synchronization of neurons, the biological network of the neuronal population is considered, and the suggested stimulatory ability is investigate in their desynchronization. Considering the many applications that digital systems have, the design of analog circuits continues to apply where digital equivalents can not perform their tasks well. For example, in applications that require very low power, such as medicine, implantable elements, and portable and lightweight devices, digital circuits may not be appropriate. Also, all the signals in the real world are analog, and these analog signals will never be substitutable. For this reasons, the proposed system   is designed with analog circuits and simulated in the HSpice software.Key words: synchronization, stimulation, astrocyte, neuronal population, analog circuit design.  

Self-repairing is among the principal foundations of biological neural networks, upon which, adjacent synapses undertake functions of defected synapses to avoid disturbances in the network function, ending up compensating the incurred error. In the present research, a self-repairing analogue circuit is designed using an astrocyte-neuron relationship. The designed circuit is based on a software model of an astrocyte-neuron network with proven ability to detect errors and undertake self-repairing. The results obtained of the proposed circuit show that, when an error occurs in the synapses associated with a neuron, the currents of healthy synapses of the same neuron increases. This increase is made by receiving a feedback from adjacent astrocytes. This process maintains the network function and compensating the incurred error in the network. To the best of our knowledge, this is the first report to present a neural network-based analogue circuit with self-repairing capability considering the effect of astrocytes. In this research, the proposed circuit was designed and simulated in HSPICE software using standard 0.35 ?m CMOS technology.

در اين پايان نامه به كمك رزوناتورهايTشكل ونيمدايره اي يك فيلتر پايين گذر طراحي، شبيه سازي و ساخته شده است. اين فيلتر داراي فركانس قطع GHz34/1است و همچنين تيزي آن از سطح dB3 تا dB40 برابر GHz41/0 است. همچنين باند قطع اين ساختار از فركانس GHz68/1 تا GHz20 مي­باشد كه نشان مي­دهد فيلتري با پهناي باند قطع عريض طراحي شده است و سطح حذف هارمونيك در باند قطع اين فيلتر برابر dB20 است. اندازه اين فيلتر برابر 9mm2/15 ×3/9مي­باشد كه با اين خصوصيات، اين فيلتر از ضريب شايستگي67954 بهره مي­برد. لازم به ذكر مي باشد كه در اين پايان نامه، فيلتر پايين گذر طراحي شده به چند رزوناتور   تقسيم شده و اين فيلتر ساخته شده است كه مشاهده مي شود پاسخ ساخت و شبيه سازي تطبيق خيلي مناسبي مي­باشند.  كلمات كليدي:رزوناتور،­فيلتر پايين گذر، اندازه كوچك، فركانس قطع.

  Recently, solving under determined systems is interested problem in the researchers of several science , especially that is too hard solving problem in general for reaching sparsete solution. In special term , a linear equation system can be converted to an equal convex optimization problem that has just one solution. This improvement is start for many searches and caused sparse solutions.In this thesis, we Propose a novel algorithm for sparse infiniti impulse response (IIR) filter designe. If a filter be sparse the addres and moltiplieres of zero coefficient will be deleted at last cost and complexity of implementation will redused.In recently years a lot of algorithms for sparsing signal introduced. This algorithms 0in 0in 10pt" >In this thesis we propose a novel algorithm for sparse infinitive impulse response (IIR) filter designs. The objective of the sparse digital filter design problem is to reduce the number of nonzero-valued filter coefficient.The proposed design method is i  ired by   particle swarm optimization(PSO) algorithm.This algorithm is included into two stages ,a preliminary optimization stage is introduced to determine the positions of filter coefficients to be zero then is reduced the error with determined the zero in first step. At last designed Butterworth IIR filter be sparse with six, zero coefficients with pass band edge .3791 , cut of frequency .531   and attenuation -45dB the   implemented on virtex6 Field Programmable Gate Array(FPGA).

  As the number of VLSI implementations of spike-based neural networks is steadily increasing, it is important to design spike-based learning algorithms and circuits which are compatible with these systems. The circuits must have adaptation and complex patterns classification capability. Spike-based learning circuits typically are used in conjunction with linear integrate and fire neurons. As a new class of current-mode conductance-based silicon neurons has beenrecently developed, it is important to evaluate how the spike-based learning circuits perform. In this research we propose VLSI implementation of a spike-based learning circuit which consists of a post-synaptic weight control module and a pre-synaptic weight update module. We propose a new circuit for the post-synaptic weight control module which consists of a generalized I&F neuron circuit, Diff-Pair integrator as synapse, voltage comparator, WTA circuit as current comparator and astrocyte circuit. Simulation results also show that the astrocyte performance as a part of current comparator is quiet acceptable.

desing of high gain LNA for bluetooth Application

فيلتر ميان نگذر جذبي و انواع آن

Design, Simulation and Fabrication of microstrip ultra- wide band (UWB) band pass filter (BPF) with triple notched using stepped impedance resonator.

  Design of Compact Quad-Band Bandpass Filter with Simple Structure and Controllable Frequencies Using Single Rectangular Ring Resonator

The human brain is composed of neurons with a Switching speed of about second. Studying spikey neural network(  )s, including modeling, simulation and implementation of a biological neuron model, helps to learn about brain and cure related diseases or to design more efficient processors and smarter robots. Such applications, made this part of neuromorphic researches so popular.   In this paper, Wilson neuron model has been simulated and implemented as an acceptable approximation of Hodgkin & Huxley (1952) biological model that is more adjusted for efficient implementation on digital platforms such as FPGA. According to results, proposed model can adequately describe neuron favorable behaviour. Hardware implementation on FPGA shows that the modified model imitates the biological behavior of different types of neurons, besides using feasibility, targeting a low-cost and high efficiency.   

Design and feasibility analysis a micro device for micro particle separation magnetophoresis

Compact ultra-wide stopband lowpassfilter using modified rectangular resonatorloaded by stub  

طراحي يك تقويت كننده كم نويز و بهينه سازي تابع نويز توسط الگوريتم هاي بهينه سازي در متلب

  Each part of the blood provides important information for diagnosis and treatment. Mineral-rich blood plasma biomarkers, including: proteins, metabolites and Etc. To access this information must first be separated from the blood plasma. Separate the plasma from the blood stages, which are the blood has different biological properties such as derivatives with platelet and white blood cells and red blood combined [27]. The classic method for separating plasma from blood, by sedimentation [28].The classic method for separating plasma from blood, is deposition method [28] based on the law of gravity and density differences in blood separation is performed, but due to the low speed centrifuges to speed up this method of precipitate action used be. This method is currently used in many laboratories. The use of centrifuges in addition to being expensive and require professional training, may cause degradation of the target (plasma proteins and metabolites) is also. With the advent and development of MEMS, plasma separation methods in the field of micro is considered. The benefits of micro-scale separation can be compared to the classic method: use a small amount of blood, portability and low price point make microdevice. In this thesis microdevice to separate the plasma from the whole blood-based MEMS technology is presented. The advantage of this method compared to other separation methods is that active and passive separation takes place, and this makes the advantages of both methods have together. The proposed method measures different from other methods of separating the samples were gathered and tried to optimize it. Among the advantages of this method to other methods this method is that continuity errors such as human error is significantly reduced.

  In this thesis two new compact size high selective microstrip bandpass filters for X- and Ku-band are proposed. The presented structure uses T-shaped resonators with direct connected orthogonal feed lines. The T-shaped resonator provides high selectivity for the proposed filter and reduces the overall size of the filter, compared with conventional uniform stub. Due to its symmetrical structures, it can be analysed with the odd and even mode. Two filters at X- and Ku-band, respectively with fractional bandwidth of 30.3 % and 37 % were realized on a Roger 5880 substrate with dielectric constant of 2.2 and 15mil thickness. Simulation and experimental results demonstrate good agreement.

 synapses are the essential part for neural network that transmit the information between neurons. The biological neuron transmits electrical or chemical signal between neurons. When the pre-synapse receives a spike, it releases the neurotransmitters and cause to active receptors in the post-synapse. After receive enough neurotransmitters from pre-synapses, the post-neuron reaches threshold voltage, the action potential is occurred in post-neuron. So, with this way the information transmit between neurons  The synapse electrical circuit is the most important parts in neuromorphic that transmit the information between neurons. In this paper we propose a modified Differential Pair Integrator (DPI) synapse circuit that can remove problems of previous synapse circuits by producing standard first-order differential equation. The proposed circuit works in sub-threshold region with low power consumption and has biological time constant   in low supply voltage (1Volt). This circuit can tune the gain and time constant with three separated controlling voltages and can play a crucial role for learning neural codes and encoding spatiotemporal spike patterns linearly in biological frequency range. This circuit has good performance and advantages in comparison with different synapse circuits, so it is suitable for applications in reconfigurable neuromorphic devices which implement biologically brain circuits. The proposed circuit is designed at 0.35µm standard CMOS technology and simulated by Hspice software.   Keywords: neuron; synapse;DPI synapse circuit; sub-threshold; low power;