Characteristics of FeCuAl Powder Compacts Sintered at Different Schedules

This paper presents the characteristics of FeCuAl powder compacts formed through uniaxial die compaction process and sintered at different schedules. Elemental iron, copper, and aluminum powders were blended mechanically and the blended powder mass was subsequently compacted at..

Fractal Yagi-Uda antenna for WLAN applications

This paper describes the development of a Fractal printed Yagi-Uda antenna for Wireless Local Area Network (WLAN) applications operating at 2.4 GHz frequency. In miniaturizing the dimensions of an antenna, fractal method is applied where the 1st iteration and 2nd iteration is implemented. The Computer Simulation Technology (CST) software is used as the platform to design and simulate the antenna. The substrate material used is the FR-4 board which has a dielectric constant of 5.4, the thickness of 1.6mm and tangent loss of 0.019. The antenna performance interm of the reflection coefficient, radiation pattern and gain are compared and analyzed. For the 1st iteration, 22.81% of reduction size has been achieved and 30.81% reduction of the antenna size for 2nd iteration has been achieved

Video monitoring application using wireless sensor node with various external antenna

Surveillance and monitoring has become very important for security reasons these days. The use of wireless sensor node device offers a variety of platform depends on the attached sensor. When an image sensor is attached, the wireless sensor node is capable of monitoring an area wirelessly. Since wireless environment uses antenna to transmit and receive data, antenna is an important component that affects the video monitoring performance. This paper describes a surveillance system using Raspberry Pi with various external antenna. The Raspberry Pi with Pi Camera module and various types of antennas was used for testing and experimentation in line-of-sight (LOS) and non-line-of-sight (NLOS) condition. The results revealed that the Yagi Uda antenna gives the best output in terms of its signal strength and average Receive (Rx) rate

Process involved in designing of an intelligent additional track mechanism tracked vehicle for swamp peat terrain

Different types of off road vehicles are widely used in agriculture, oil industry, mining and military operations but none of them can effectively operate over the swamp peat terrain because of its low bearing capacity of 7kN/m 2. Segmented rubber tracked vehicle and intelligent air-cushion system tracked vehicle were developed in Malaysia for swamp peat terrain.16kN/m2 of ground pressure was exerted by using the segmented rubber tracked vehicle during field operation therefore could not be operated efficiently. The air-cushion tracked vehicle increased the floatation capacity but at the same time increased the frictional effects therefore the tracks of the vehicle easily slipped out from the traction wheels during operation. Addressing these issues an intelligent additional track mechanism for tracked vehicle has been designed to improve the mobility over swamp peat terrain where the additional track would be increased the ground surface area and reduced the vehicle ground pressure. This paper presents the process involved in designing the intelligent additional track mechanism tracked vehicle for transportation of agricultural and industrial goods on the swamp peat terrain with bearing capacity of 7kN/m2. The mechanical design comprises of track vehicle frame with track mechanism. Additional track mechanism with Fuzzy expert system. The design parameters are optimized using developed mathematical model based on the dynamics and kinematics behavior of the vehicle. In order to increase the vehicle contact surface area and reduce the surface contact pressure the additional track mechanism is designed in such way that it can be folded and unfolded from its position by using the ball-screw scissor lift mechanism. While, Fuzzy expert system is used to control the movement of the lift mechanism based on 70mm critical sinkage of vehicle detected from a set of sensors. The completed to vehicle system would be used for off-road applications as required

International Forum for Rural Development

Somalia's first issue of complexity is found in its relentless political crises: constant conflict in the country has led to a political and normative void and has discouraged long-term supporters of community reconstruction. The second issue of complexity is found in development strategies promoted by International Agencies, much more focused on re-establishing the state's legal and institutional structures rather then sustaining a process of construction of community social purpose shared by all clans: this feature is at the basis of political and social identity funding principles of any functioning national state. The third issue of complexity is found in defining the best policy approach in International Cooperation, in regard to beneficiaries and donors. The objective of the present report is to design a development strategies for rural areas in the actual fragile context in order to help local communities in fostering their development capacity, based on the idea of bottom-up development approach

Fluorous Molecules for Dye-Sensitized Solar Cells: Synthesis and Photoelectrochemistry of Unsymmetrical Zinc Phthalocyanine Sensitizers with Bulky Fluorophilic Donor Groups

Two sterically hindered zinc phthalocyanines bearing fluorous alkoxy substituents and carboxylic acid groups acting respectively as electron donor and electron acceptor/anchoring units, were synthesized and their ability to photosensitize nanocrystalline TiO2 films was investigated. The electronic properties of these new dyes were characterized by combining UV-vis spectroscopy, electrochemical techniques and DFT computation. Nanocrystalline TiO2 electrodes treated with the fluorous dyes were assembled in dye-sensitized solar cells (DSCs) and further characterized by photocurrent action spectroscopy, photocurrent-photovoltage measurements and electrochemical impedance spectroscopy. The maximum photon-to-current conversion efficiencies (IPCE) in the near IR region compared favorably with those achieved with some of the best phthalocyanine dyes investigated so far, thus highlighting the potential of fluorous molecules as DSC components. A maximum power conversion efficiency (?) of 1.3% was attained in the absence of any additive such as antiaggregating chenodeoxycholic acid or conduction band edge modifier tert-butylpyridine. The basic information gathered in this study will serve as guidelines for the design of new fluorous dyes for highly efficient DSCs. © 2011 American Chemical Society