Size Reduction and Gain Enhancement of a Microstrip Antenna using Partially Defected Ground Structure and Circular/Cross Slots

Microwave engineers have been known to designedly created defects in the shape of carved out patterns on the ground plane of microstrip circuits and transmission lines for a long time, although their implementations to the antennas are comparatively new. The term Defected Ground Structure (DGS), precisely means a single or finite number of defects. At the beginning, DGS was employed underneath printed feed lines to suppress higher harmonics. Then DGS was directly integrated with antennas to improve the radiation characteristics, gain and to suppress mutual coupling between adjacent elements. Since then, the DGS techniques have been explored extensively and have led to many possible applications in the communication industry. The objective of this paper is to design and investigate microstrip patch antenna that operates at 2.4 GHz for Wireless Local Area Network WLAN IEEE 802.11b/g/n, ,Zigbee, Wireless HART, Bluetooth and several proprietary technologies that operate in the 2.4 GHz band. The design of the proposed antenna involves using partially Defected Ground Structure and circular/cross slots and compare it to the traditional microstrip patch antenna.  The results show improvement in both the gain of 3.45 dB and the S11 response of -22.3 dB along with reduction in the overall dimensions of the antenna. As a conclusion, the performance of the antenna has been improved through the incorporation with the DGS and slots structures regarding the S11 response and the gain. The proposed antenna become more compact. Finally, the radiation pattern of proposed antenna has remained directional in spite of adding slots on the ground plane

Communication system improvement with control performance based on link quality in wireless sensor actuator networks

New communication and networking paradigms started with wireless sensor actuator networks (WSANs) to introduce new applications. One of these is the automatic gain control system (AGC). It will enable a high degree of the decentralized and mobile control. In this study, neural networks (NN) with fuzzy logic (one of the techniques of artificial intelligence (AI)) is used to enhance the control performance depending on the link quality. The NN and fuzzy inference system (FIS) with Mamdani’s method used to build a model reference, adaptive controller, for recompensing for delay time packets losses, and improving the reliability of WSAN. Between 88.62% and 99.99%, validation data is obtained for the medium and high conditions of operation with the proposed algorithm. Experimental and simulation results show a promising approach

Comparison of Clinico-Pathological Presentations of Triple-Negative versus Triple-Positive and HER2 Iraqi Breast Cancer Patients

BACKGROUND: Breast cancer remains the most common malignancy among the Iraqi population. Affected patients exhibit different clinical behaviours according to the molecular subtypes of the tumour. AIM: To identify the clinical and pathological presentations of the Iraqi breast cancer subtypes identified by Estrogen receptors (ER), Progesterone receptors (PR) and HER2 expressions. PATIENTS AND METHODS: The present study comprised 486 Iraqi female patients diagnosed with breast cancer. ER, PR and HER2 contents of the primary tumours were assessed through immunohistochemical staining; classifying the patients into five different groups: Triple Negative (ER/PR negative/HER2 negative), Triple Positive (ER/PR positive/HER2 positive), Luminal A (ER/PR positive/HER2 negative), HER2 enriched ((ER/PR negative/HER2 positive) and all other subtypes. RESULTS: The major registered subtype was the Luminal A which was encountered in 230 patients (47.3%), followed by the Triple Negative (14.6%), Triple Positive (13.6%) and HER2 Enriched (11.5%). Patients exhibiting the Triple Negative subtype were significantly younger than the rest of the groups and presented with larger size tumours. A significant difference in the distribution of the breast cancer stages was displayed (p < 0.05); the most advanced were noted among those with HER2 enriched tumours who exhibited the highest frequency of poorly differentiated carcinomas and lymph node involvement. CONCLUSION: The most significant variations in the clinicopathological presentations were observed in the age and clinical stage of the patients at diagnosis. Adoption of breast cancer molecular subtype classification in countries with limited resources could serve as a valuable prognostic marker in the management of aggressive forms of the disease

Computer Simulation of PMSM Motor with Five Phase Inverter Control using Signal Processing Techniques

The signal processing techniques and computer simulation play an important role in the fault diagnosis and tolerance of all types of machines in the first step of design. Permanent magnet synchronous motor (PMSM) and five phase inverter with sine wave pulse width modulation (SPWM) strategy is developed. The PMSM speed is controlled by vector control. In this work, a fault tolerant control (FTC) system in the PMSM using wavelet switching is introduced. The feature extraction property of wavelet analysis used the error as obtained by the wavelet de-noised signal as input to the mechanism unit to decide the healthy system. The diagnosis algorithm, which depends on both wavelet and vector control to generate PWM as current based manage any parameter variation. An open-end phase PMSM has a larger range of speed regulation than normal PMSM. Simulation results confirm the validity and effectiveness of the switching strategy