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In the earlier stage of 1500 BC’S composites were invented. The initial stage of composites was created with the help of mixing the mud and straw for construction purpose, in order to build strong and durable component in the view, to ensure the longer life on the products. After some years, the usage of composite materials is become more, depends on different applications such as appliances, construction, electrical distribution, energy and marine usages and so on. Since the past few decades’ natural fibres plays a vital role in structural applications such as ease of fabrication, low cost, high durability, and for low thermal properties. In the present experimental investigation work, jute fiber has been chosen as the reinforcement agent along with the epoxy matrix material. With help of the hand layup technique the composites have been fabricated along with the standard ratio of (3% & 6%) calcium carbonate as the filler material. The fabricated jute fiber reinforced epoxy matrix (standard ratio of calcium carbonate filler) laminate were cut as per the ASTM standards to do the tests like tensile, flexural & impact, in order to completely analyse the physical strengths of the laminate, and the same data’s were compared with filler materials and without filler material. At last the fractured surfaces were thoroughly investigated with help of scanning electron microscope to understand the morphological behaviour of the fabricated composite.

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In recent years, concrete-filled steel tube (CFST) has gained attention in the construction sectors due to its unique static and earthquake resistant properties. The steel-concrete composite member is formed by filling the concrete inside the hollow steel tube of various shapes. The experimental and numerical investigations were carried out for CFST members filled with different types of concrete of the same grade. The types of concrete used for this study are conventional concrete, steel fiber-reinforced concrete, geopolymer concrete, and expansive concrete, respectively. The concretes were cast in the form of cubes followed by curing underwater and self-curing conditions. The specimens cured for 7 and 28 days of age were subjected to axial compressive strength testing. The effect of curing conditions on the strength of concrete was evaluated by comparing the obtained results. Self-curing, the only possible way of curing infilled concrete in the case of CFST columns, was found to have no influence on the strength of concrete, and the same curing method was adopted for the CFST columns tested in this study. A total of 24 CFST specimens were cast by different types of concrete infill, and their load carrying capacity under axial compression and their bond strength were determined through experimental investigations. The characteristic strengths measured for the CFST columns with different types of concrete infill were compared, and the results are presented. The analytical investigations were carried out by using Eurocode-4 to predict the load-bearing capacity of CFST columns under axial compression. Finally, the load carrying capacities of CFST columns under axial compression obtained through experimental and simulation studies were compared and the results are presented.

Software Defined Radio aims at using the same hardware for different applications by the change in software parameters. The reconfigurable part in a Software Defined Radio is the Digital Front-end and the parameters which can be modified for different standards and technologies include bandwidth, Sampling Frequency, down converted IF, up converted IF and filter cut-off frequencies. The major goal for an ideal Software Defined Radio is to place the ADC as close to the antenna as possible. This can be achieved by Band-pass Sampling. Automatic Modulation Identification (AMI) can be used in conjunction with the design principles of Software Defined Radio to make the transceiver more flexible. The main objective of this paper is to address the concepts involved in the design of RF front end of a Software Defined Base Transceiver Station (BTS) which can be configured to support different technologies (here GSM/IS-95) depending on the software modifications. Index Terms-Automatic Modulation Identification (AMI), Base Transceiver Station (BTS), Band-pass Sampling and Software Defined Radio (SDR).978-1-4244-4067-2/09/$25.00