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Mutual coupling of closely spaced microstrip antennas is an undesirable phenomenon which degrades the antenna performance like gain, radiation pattern, return loss characterizes etc. This paper presents two identical circular microstrip antennas integrated with a microstrip resonator. This resonator acts as an electrical wall between two circular patches and reduces the mutual coupling up to 25 dB. Centre to centre spacing between the circular microstrip antennas is 0.028 ?. The resonating frequency of these antennas is 8.8GHz which is useful for the X band application. This multiple-input-multiple-output (MIMO) antenna structure is specifically applicable to satellite communication and radar system.

Minority carrier life time and diffusion length of solar photovoltaic devices were measured. Minority carrier diffusion length is one of the essential characteristics of semiconductor materials, and there is a great deal of interest in it as a quality and process parameter in the fabrication of solar cells. Diffusion length can be used as an indicator of the efficiency of a solar cell. Bulk resistivity of the samples were measured which is in the range 0.8 – 1.2 ?-cm, diffusion length of in the range 250 – 390 ?m and minority carrier life time is in the range 1.83?10-5 to 4.47?10-5 sec. The spectral response of the deposited sample also measured and plotted.

Over the past few decades the mounting demand for wireless and broadcast communication has stimulated a striking increase in steel telecommunication tower construction and maintenance. Failure of such structures due to the most destructive and unpredictable catastrophe, earthquake, is a foremost concern. The Indian Standard (IS) provides the static analysis provisions for stack-like structures including transmission towers but excluding telecommunication towers. The code suggests following Equivalent Static Load (ESL) method for the seismic analysis of such structures. In this paper, the IS provisions for transmission towers are being considered to analyze the telecommunication tower with some modifications and the same design of the tower is exposed to real-time earthquake ground motions to examine its adequacy in real-life disasters. A specific model of self-supporting tower is taken into account for performing the ESL method to check whether the structure is adequate for all critical conditions mentioned in the codal provisions of the transmission tower. Furthermore, that particular model is exposed to the real-time ground motions using Time History Method (THM) to check the compatibility between the analytical designs using codal provision and real-time disasters.

The present study analyses the nasal airflow signal obtained from the nasal thermistor to diagnose obstructive sleep apnea syndrome (OSA). Using signal processing techniques, a wide set of features were extracted from the airflow signals of 41 subjects who were undergone polysomnography study. The subjects were divided into two groups: OSA (36) and non-OSA (5). The feature set included time and frequency domain features. Feature selection was performed using Recursive Feature Elimination (RFE) technique followed by Linear Support vector Machine (SVM) based classification to classify between the groups. The proposed system collects respiration signal from a thermal sensor into a smartphone with the help of Bluetooth communication port. The event detection accuracy of the proposed system was found to be 96.53% during the online testing process at the laboratory. The proposed smartphone-based system can also communicate to some remote computer in real-time through GPRS/UMTS wireless Network available worldwide and can also, be used to initiate an alarm when the event prolonged more than 10 sec In the smartphone, a Support Vector Machine (SVM) based binary classifier was implemented, which classifies a typical eight sec buffered/windowed respiration signal into Normal (N) and Disordered (D) breathing state.

In this era of high-end electronic gadgets dominated by the semiconductor industry, all researches are mainly focused on discovering new semiconducting materials for developing low cost, high performance, and maximum durability devices. In this process, Chalcogenide glasses are one the vital candidates as they meet around all the above criteria and because of its fascinating thermal, electrical, optical and structural properties they have already found many end applications. Here, a review on few recent discoveries of Chalcogenide glasses has been reported.

In this paper microstrip antennas with different regular shaped patches with a novel saw tooth defective ground structure are proposed and a comparative study between the structures is presented. In the absence of the defective ground structure (DGS) the structures are found to be resonant at 5.2 GHz. When the DGS are introduced multiple resonances are observed. The main essence of this paper is the miniaturization of the antennas and a comparative analysis is drawn in this context.

In this paper microstrip antennas with different regular shaped patches with a novel saw tooth defective ground structure are proposed and a comparative study between the structures is presented. In the absence of the defective ground structure (DGS) the structures are found to be resonant at 5.2 GHz. When the DGS are introduced multiple resonances are observed. The main essence of this paper is the miniaturization of the antennas and a comparative analysis is drawn in this context.

Digital mine is an imitated form of realistic underground mining circumstance presented on a computer display. With the help of the Internet of Things (IoT), the sensors ensure to create the conditions of virtual reality aiming to get some vivid idea of the operable mining situations for monitoring several mining parameters. Thus, it plays an essential role during various mining activities such as decision-making and proper management, mining operations, mine safety aspects, maintaining an amiable mine environment, etc. The IoT can be used as a preventive measure for the rescue of the trapped miners and restoring the mining status after post mine accidents. Electronics devices like sensors, actuators, RFID devices, gateway, and 3D display unit passes the information to the IoT to build a foundation for recognizing, accumulating, and processing the gained knowledge. Thus, IoT has enhanced mining productivity by reducing mine accidents and creating a safe environment for mine workers. A 3D virtual mine system has been developed to monitor and predict underground mining hazards for increasing safety and productivity.The integrated system includes different modules covering miners tracking and voice communication, environment and gas monitoring, strata monitoring, store inventory management, online production and dispatch monitoring, personnel management, fire and explosivity status monitoring, etc. The paper enumerates the concept of digital mine and details of different modules developed to monitor, analyze, and visualize various mining activities, predict impending hazards, and give warning.

A theoretical analysis following an analytical and CFD approaches is performed on an indigenously designed device by CSIR-CMERI which can be used to save a person from drowning. The device is ultra-light in weight and very simple to use having a double fastener arrangement to secure it tightly with the human body. A detailed hydrodynamic analysis is performed in this article to understand the effectiveness of the device. The analysis includes the calculation of the buoyant forces acting on the device under a static condition to understand its floatation characteristics. A dynamic analysis is also carried out in order to delineate the role of various forces acting on the device and the expected behavior of it under the dynamic condition. An experimental study conducted subsequently has confirmed the low water absorptivity of the material used in the manufacturing of the device. Finally, three different shapes are identified to analyze the fluid dynamic aspects using a computational fluid dynamics (CFD) technique and based on the numerical study the final shape of the device is selected.

SAP is at the core of enterprise IT strategy. The new age applications running on SAP S/4 HANA claim huge server space and require advanced monitoring processes for optimal outcomes. Given the server bandwidth required, running it on premise is not as productive. The cost, resource and time intensive complex deployment processes add further barrier to scalability. Cloud deployment, with cost optimized easy scalability, security and accessibility is thus the only viable option. However, the journey to cloud is not linear and weighs on the minds of the CIO/ CTOs. The cloud deployment is one part of the story; the more critical aspect is to manage the workloads on a daily basis.