Synthesis of Biodiesel from a Crude Blend of Palm Oil and Rubber Seed Oil

Biodiesel industry is expanding as new challenges arise from environmental impacts caused by hydrocarbon based fuels. However, the industry has shown some downfall recently due to the increasing demand of vegetable oils for human nutrition's need. Crude rubber seed and palm oils were used in this study to synthesize biodiesel since both can be extracted and produced here in Malaysia from their abundant plantations. The respective oils and the blends were characterized. An equi-volume blend of crude palm oil and rubber seed oil was chosen for biodiesel synthesis and exhibited the following properties: density of0.91754 g/cm3, viscosity of39.35cP, heating value of 38.1 MJ/Kg, acid value 31.4, FFA 11.9%, refractive index of 1.465, mono-,di- and triglycerides were 2.5, 7.3 and 70 wt%. Sulfur content was acceptable at 0.03 lwt%. Fstty acid composition for the oil blend was established and the calculated iodine value was 106.3. Two stage transesterification is performed in this study to remedy the high acid value of the oil blend. Design of experiments using taguchi technique was used to study the interaction of parameters involved in the production. Temperature, alcohol and catalyst amount were studied independently for both acid and base reactions to find their relevant effects. The optimum operating conditions for acid esterification which could reduce the FFA% to lower than 0.6% were 65°C, 15/1 methanol to oil ratio and 0.5wt% catalyst. The optimum operating conditions for base transesterification were 55°C, 8/1 methanol to oil ratio and 2wt% potassium hydroxide which could achieve the highest possible conversion to methyl esters exceeding 98 %. The quality of biodiesel produced matched that of international standards. The kinetics of free fatty acids alcoholysis in acid esterification was investigated and the rate equation had a reaction order of (2.24). Rate constant was (6.769xl03 lit/gmol.min) while the activation energy and Arrhenius constant were 60.289 and 14.06 x 109 KJ/g respectively. A nonlinear model was developed and with experimental data to predict FFA concentration change throughout the reaction. Kinetics of methyl ester formation in base transesterification was studied using differential method. Three techniques were applied, namely, graphical method, finite difference and linear regression. None of which could predict a rate law to represent the reaction. Consequently, a model was developed to represent the rate of reaction and the system using nonlinear regression of the experimental data

GSU Event Portal

This sophisticated web application, GSU Event Portal, would allow visitors to search for events happening around the city with the ability of paying for interested up-coming event using a debit/credit card. As the name implies, this web application would display tangible information of such event to event goers. The technology behind this application is to make visitors more informative and feature in dynamic events which might be live music, live festivals and many more. On the user interface, visitors should be able to search for up-coming events by city, time and event type. The result of the search would provide all events that will be happening at the specified time based on a visitor’s search criteria. Event organizers would as well be able to advertise their events ahead of time. The web application will be available on any device that could browse with internet connected and will be designed in three consoles: The Organizer console, Admin console and user interface. Organizer console will be able to create and edit events, view registration for an event and verify payments. The Admin console will be able to give permissions to Organizers and visitors, edit user’s profile and delete user account. The User interface console will be available to visitors and users who would like to register for an up-coming event. In addition to that, it will include map functionality that will show the event location on map. Visitors can only view event listings but to participate in an event, registration would be required for allocation of space

Multilayer nanoparticle arrays for broad spectrum absorption enhancement in thin film solar cells

In this paper, we present a theoretical study on the absorption efficiency enhancement of a thin film amorphous Silicon (a-Si) photovoltaic cell over a broad spectrum of wavelengths using multiple nanoparticle arrays. The light absorption efficiency is enhanced in the lower wavelengths by a nanoparticle array on the surface and in the higher wavelengths by another nanoparticle array embedded in the active region. The efficiency at intermediate wavelengths is enhanced by the simultaneous resonance from both nanoparticle layers. We optimize this design by tuning the radius of particles in both arrays, the period of the array and the distance between the two arrays. The optimization results in a total quantum efficiency of 62.35% for a 300nm thick a-Si substrate.Comment: - Article Published in Optics Express on 7 Apr 2014. Link: http://www.opticsinfobase.org/oe/abstract.cfm?uri=oe-22-103-A80

Reduced Complexity Optimal Hard Decision Fusion under Neyman-Pearson Criterion

Distributed detection is an important part of many of the applications like wireless sensor networks, cooperative spectrum sensing in the cognitive radio network. Traditionally optimal non-randomized hard decision fusion rule under Neyman Pearson(NP) criterion is exponential in complexity. But recently [4] this was solved using dynamic programming. As mentioned in [4] that decision fusion problem exhibits semi-monotonic property in a special case. We use this property in our simulations and eventually apply dynamic programming to solve the problem with further reduced complexity. Further, we study the e�ect of using multiple antennas at FC with reduced complexity rule

A Hierarchical Approach for Investigating Social Features of a City from Mobile Phone Call Detail Records

Cellphone service-providers continuously collect Call Detail Records (CDR) as a usage log containing spatio-temporal traces of phone users. We proposed a multi-layered hierarchical analytical model for large spatio-temporal datasets and applied that for the progressive exploration of social features of a city, e.g., social activities, relationships, and groups, from CDR. This approach utilizes CDR as the preliminary input for the initial layer, and analytical results from consecutive layers are added to the knowledge-base to be used in the subsequent layers to explore more detailed social features. Each subsequent layer uses the results from previous layers, facilitating the discovery of more in-depth social features not predictable in a single-layered approach using only raw CDR. This model starts with exploring aggregated overviews of the social features and gradually focuses on comprehensive details of social relationships and groups, which facilitates a novel approach for investigating CDR datasets for the progressive exploration of social features in a densely-populated city

Development of Powder Metallurgy (PM) compacted Cu-TaC electrodes for EDM

The main aim of this paper is to investigate the properties of Cu-TaC electrodes produced by Powder Metallurgy (PM) method. The design of Experiment (DOE) method was used to plan the investigation. Two different compositions of the powders (Cu-TaC with 30 and 55 % wt TaC) were used. The major properties which determine suitability of electrodes for Electro Discharge Machining (EDM) are electrical conductivity, thermal conductivity and to some extent density. These properties were measured for the green compacted electrodes, analyzed and compared with their sintered counterparts. This is the initial stage to determine the suitability or otherwise of the compacted electrodes. The results showed that the compacted electrodes in green form can be suitable for EDM, since the electrical conductivities are very high (94.96-189.92�-1m-1). The thermal conductivity is good (29.70-33.20W/ m K). The density ranges between 6.13 and 9.80 g/cm3. The sintered electrodes were found to be unsuitable at the specified conditions, because they became non-conductive electrically after sintering. Current efforts are geared towards improving these properties for the sintered ones and also determining their optimum levels