Assessment of static and dynamic stresses horse-shoe tunnel with connecting gallery using finite element method: (as a case study)

This paper illustrates the use of MIDAS GTS NX to investigate the tunnel’s simulation in order to highlight the effect of static and dynamic load on the behaviour of tunnel to compare this response expressed in terms of displacement and stresses acting on the tunnel and ground. Main tunnel is located in the ground having uniform property throughout its extent, connecting gallery is located perpendicular to the main tunnel, the shotcrete and rock bolts for each tunnel will be installed

A Novel Approach for Adsorption of Copper(II) Ions from Wastewater Using Cane Papyrus

Abstract:                 This study tested the suitability of  Cane Papyrus as a  biological sorbent  for the  removal of  copper ions (Cu2+) from  industrial  wastewater. Bath mode was  used and the effects  of the  following parameters  were investigated: adsorbent dosage (10 to 50 g/L), pH value (2 to 8.0). The Cane Papyrus were  characterized  by Fourier  transform infrared spectroscopy (FTIR)   Cu2+ions adsorption. The results revealed a higher efficiency of powdered adsorbents for Cu2+ removal. The highest adsorption efficiency was found to occur at pH 6 with 50 g/L Cane Papyrus for an experimental duration of 2 hours. These  derivatives  are  probably responsible  for  Cu2+  chemical  adsorption. The Freundlich isotherm model more suitably described the adsorption process than the langmuir model with linearized coefficients of 0.95 and 0.844 respectively. Pseudo-second order kinetic equation best described the kinetics of the reaction. Fourier transform infra-red analysis confirmed the presence of amino (–NH), carbonyl (–C=O) and hydroxyl (–OH) functional groups. Furthermore, 0.5M HCl was a better desorbing agent than 0.5 M NaOH and de-ionized water. The experimental data obtained demonstrated that Cane Papyrus  can be used as a suitable adsorbent for Copper(II) ion removal from wastewater.   Â

WLAN Integrated with GPRS Network Securely

In this paper a WLAN network that accesses the Internet through a GPRS network was implemented and tested. The proposed network is managed by the Linux based server. Because of the limited facilities of GPRS such as dynamic IP addressing besides to its limited bandwidth a number of techniques are implemented to overcome these limitations.Dynamic Host Configuration Protocol (DHCP) server was added to provide a single central control for all TCP/IP resources. Squid Proxy was added to provide caching of the redundant accessed Web content to reduce the Internet bandwidth usage and speeding up the clients download time. Network Address Translation (NAT) service was configured to share one IP address among several different systems. In order to accomplish a secure channel to exchange data between two network devices, the Secure Shell (SSH) protocol was added. The first test shows that the data transfer rate at different time intervals of the day found to be an average of 10.95 Kbps for uploading and 13.7 Kbps for downloading and the second test shows that the network performance improved when squid proxy cache was used. The data rate found to be 143.3 Kbps average for uploading rate and 376.6 Kbps average for downloading rate

Development of rapid charging system for EV battery

The adaption of electric vehicle in worldwide is increasing in acceleration fashion while in Malaysia has been a slow hike, especially with the lack of infrastructure development. There are few conventional charging stations of EV are set up in shopping malls and hotels are not enough to initiate the EVs in the country. However, the charging awaiting time is quite longer could be about 5 to 6 hours which makes Malaysia is slowly falling out from EV trend. The development of a quick charging system from this study might be considered as the development of electric mobility solutions. A prototype onboard charging system with three different charging modes: the slow charging mode is normally considered for residence, medium charging mode for office parking lots, and fast charging mode for charging station on road. The quick charging mode has been developed to charge the battery in 1.5 - 2.0 hours with a maximum charging current 50 A with auto-activated quick evaporative battery thermal management system. The performance of the quick charging system has shown that the battery to charge up to 85% of its rated capacity by constant current mode rather than a constant voltage, which has shortened the battery charging time by 16%. However, it might shorten the battery life by about 5% due to the fast redox reaction of the electrochemistry of battery

Design of Wireless Monitoring and Controlling System of Power Transmission Lines

In the traditional overhead power transmission lines systems, detection of the faults in electric lines is more difficulty, and leads to take more times to  repair it. The faults resulting from  loads or current leakage are difficult to detect. This paper offers a monitoring system for the weather conditions such as humidity, temperature, and rainfall, and also monitoring the current flow of the line to detect the faults and specified the fault region. The system disconnect the power when an over value exist. The design consist a group of nodes, each one contains a transmitter and receiver unit. The transmitter consists of group of sensors DHT11 sensor, Rain sensor and ACS755 which sends the measured information as frames via Xbee technology. All these nodes send their data to the main node. Virtual Serial Port Emulator VSPE used to access multiple nodes on the main pc. The results in this paper shows the performance of the system when all the parameters were within the allowed range. The design also was simulated in different out range values of over current, high humidity and high rainfall. The obtained results were accurate and prove that it works successfully

Simplified finite element approximations for coupled natural convection and radiation heat transfer

This article focuses on the effect of radiative heat on natural convection heat transfer in a square domain inclined with an angle. The left vertical wall of the enclosure is heated while maintaining the vertical right wall at room temperature with both adiabatic upper and lower horizontal walls. The governing equations are Navier–Stokes equations subjected to Boussinesq approximation to account the change in density. The natural convection–radiation equations are solved continuously to obtain the temperature, velocity and pressure. Taylor–Hood finite element approach has been adopted to solve the equations using triangular mesh. Effects of Rayleigh number, Planck constant and optical depth on the results are considered, presented and analyzed. Results show that the adiabatic walls, Planck constant as well as the inclined angle play an important role in the distribution of heat transfer inside the cavity

Respuesta de termoluminiscencia del sistema de vidrio anfitriónde sílice borato de zinc (ZBS) irradiado con electrones y fotones

Introduction: Glass phosphors are broadly used to determine patient doses in radiation diagnostic and radiotherapy because of their good features, the dose ranges of interest are approximately0.1 -100 mGy for clinical x-ray diagnostics, and 1-5Gy for radiotherapy. Materials and Methods: Borate silica glass samples were prepared using melt quenching technique, XRD analysis confirms that the glass system is amorphous (non- crystalline). TL properties of glass were investigated such as optimum concentration, heating rate, and annealing procedure. The optimum glass samples of 45ZnO-45B 2O3-10SiO2 are used as glass radiation dosimeter. The samples were irradiated using 6MeV and 6MV photon beams in adose range (0.5-4) Gy. Results and Discussion: There is single and wide thermoluminescence glow curve that offering with maximum intensity at about 165 oC. Linear dose-response behavior has been observed in this dose range for both irradiation electron and photon beam. Sensitivity and minimum detectable dose have been found. The sensitivity of 6MeV is 1.7 greater than the sensitivity of 6MV photon energy. Conclusions: The results point out that this glass has the potential to be used as an electron and photon radiation dosimeter