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Background & Objective: In this paper, environmental monitoring system is implemented using a wireless sensor networking (WSN) via a local internet protocol (IP) utilizing Wi-Fi media. For enchanting data, DHT-11 (Temperature and Humidity sensor) and MQ-6 (LPG gas sensor) are being used. Methods: The basic objective of this research is to monitor and to develop a real-time monitoring of humidity and temperature, as well as the availability of gas using the very available DHT-11 sensor, MQ-6 sensor, and ESP-8266 NodeMCU module and then observe the data from a local IP based webpage. Conclusion: This paper also makes a compact distinction between conventional and the local IP based observing system of an environment. The sensor's data are saved in an IP based webpage by which we can monitor the sensor’s data without any access to the internet.

A wind tunnel system for a spinning body was developed for the measurement of the hydrodynamic forces acting on the body. In that system a ferromagnetic sphere (body) was suspended and rotated by electromagnets. The forces acting on the body were measured from the control signal for suspension. However this existing arrangement is not still appropriate to observe accurate hydrodynamic phenomena around the floating object because the size of the wind tunnel is only 60×60mm. It is required to enlarge the size to reduce the interferences with the walls. In this work, a wind-tunnel system of 100×100mm is proposed to be fabricated. Before the development of the system, the electromagnetic analysis for the system has been carried out. A 3D model of the arrangement is taken in consideration for the analysis. The magnetic flux distributions as well as magnetic force acting on the suspended object are obtained. The magnetic flux densities are analyzed for the variation of current in electromagnets. Actual force acting on the body is also measured. It is observed that the experimental results support the results obtained by numerical analysis. Stable suspension and three-dimensional positioning of the body is achieved in the developed system. Spinning of the body is realized by superimposing two-phase AC signals on the control signal.

An electromagnet and a float are needed to be designed for a magnetic suspension system. In this paper an optimized design of an electromagnet is being carried out based on minimum flux leakage and maximum amount of force that can be imparted on the float. This paper also compares different designs to find out advantages and disadvantages of these designs. Design starts from a simple and naïve design of electromagnet and then gradually improved until a satisfactory design is obtained. Different shapes of floats were also considered for an optimum design of float. Electromagnetic analysis is carried with commercial FEM (Finite Element Method) software to calculate different parameters of design. Later the result from the FEM software is verified by analytical calculation.

These days, noise pollution is a major issue that affects the environment. The high amount of noise present in the industries has adverse impact on the workers, operators and people associated in those fields. The consequences could be as hazardous as heart attack or even lifelong hearing loss. Sound absorption through barriers, mufflers are some popular fields of study. Some natural extracted materials show impressive SAC at lower and mid frequencies. Moreover, natural materials usage in this field is being popular as they emit almost zero amount of greenhouse gases and their manufacturing process requires a little amount of energy to process for ready to usage. A galvanized steel pipe as the impedance tube was chosen because it is cheaper than the impedance tube available in the market. We have tried to measure sound absorption coefficient of some combinations of different materials as an acoustic barrier material.