39 research outputs found
Design of Wideband Low Noise Amplifier using Negative Feedback Topology for Motorola Application
This paper describes the design of wideband low noise amplifier (LNA) for Motorola application which targeted to be applied in two-way communication mobile system architecture. The technical specification was deduced from the TIA-603C standard receiver system sensitivity and intermodulation. The proposed LNA exhibit low power consumption and adopts a negative feedback wideband amplifier topology, operated from 100 MHz to 1 GHz which covers the whole Land Mobile FM Communication Equipment (136 – 941 MHz) frequency band. The proposed topology solve the RF tracing problem inherited in the targeted frequency and also the problem of economically impractical PCB size rendered by other wideband amplifier methods. The Advanced Design System software is used to perform the simulations. The measured result show the proposed LNA using FR4 board has a stable gain of more than 15 dB, noise figure less than 1.5 dB, S11 and S22 less than -10 dB, with current consumption of 8mA from voltage supply at 1.8
Cleaner Production Implementation using Extended Value Stream Mapping for Enhancing the Sustainability of Lean Manufacturing
This paper investigated the measures by Cleaner Production (CP) embedded in the modified VSM technique, i.e., Cleaner Production VSM (CPVSM) to be an effective visualisation technique for Lean and promoted the sustainability at 2 local Small and Medium Enterprises (SME’s) for demonstrating the level to which the CPVSM process can be applied. Our findings showed that the implementation of the CP technique was improved through this CPVSM approach and thus promoted the Lean Manufacturing (LM) sustainability
Tensile Properties of Ternary Blends for HDPE/PP/Recycle HDPE in Blow Moulding Process
Increasing the environmental concern among peoples have increased the recycling activities, especially for high-density polyethylene (HDPE) bottles. Therefore, recycled HDPE needs to be mixed with other plastic materials to improve their mechanical properties. In this study, recycled HDPE was mixed with virgin HDPE and polypropylene (PP). The ratio of virgin HDPE and PP were set at 10/90, 30/70 and 50/50, meanwhile recycled HDPE was set at 20%, 35% and 50%. The blended materials were extruded into the parison and was blown using extruded blow-moulding machine to produce a 5-litre bottle. The tensile strength and elongation at break of the blended materials were measured using universal testing machine (UTM). Miscibility of the blended materials was also evaluated using differential scanning calorimetry (DSC). The result shows that decreasing the recycled HDPE in the blended materials increases the tensile strength. Meanwhile, increasing the recycled HDPE content in the blended materials increases the elongation at break of the blended materials. DSC curve shows that blended materials are immiscible
MULTI-RESPONSE OPTIMIZATION OF PLASTIC INJECTION MOULDING PROCESS USING GREY RELATIONAL ANALYSIS BASED IN TAGUCHI METHOD
This project investigates the multi-response optimization using grey relational analysis based in Taguchi method of plastic injection mould. Four input process parameters selected are mould temperature, melting temperature, injection time and cooling time. The responses investigated were part weight, shrinkage, warpage, ultimate tensile strength, tensile modulus and percentage of elongation. It is found that the optimum setting parameter generated from multi-response optimization is at run number 4 that are mould temperature at 56oC, melting temperature at 250oC, injection time at 0.7s and cooling time at 15.4s. Result of run number 4 for multi-response optimization for part weight, warpage, shrinkage, tensile ultimate strength, tensile modulus and percentage of elongation are 6.9807g, 0.087mm, 1.73%, 24.732MPa, 981.76MPa and 31.37%, respectively. Multi-response optimization results show that all response results are not higher or lower than experimental results. This is because multi-response optimization normalized all response value. Thus, by implemented multi-response optimization process, the materials characteristics value of plastic part can be predicted
Eletroconvulsotherapy: Criteria and recomendations from World Psychiatric Association [Eletroconvulsoterapia: Critérios e recomendações da Associação Mundial de Psiquiatria]
The ethical aspects of halal certification of medical devices in Malaysia
The medical devices industry is one of the fastest growing sectors of healthcare industry with a large market, a wide
variety of products and growing applications. In Malaysia, this industry is a major contributor to the economy and
government initiatives support its growth to position Malaysia as a medical device manufacturing hub in the Asia-
Pacific region. There are more than 180 manufacturers of medical devices in Malaysia involved in the production of
sophisticated devices such as orthopedic products, surgical instruments and dialysis machines. Local companies are
moving towards complying with internationally recognized quality standards such as ISO 13485 as an attempt to
penetrate the global market. However, there is a religious need to provide medical devices that are certified halal in
order to cater to the needs of Muslim consumers who make up 64.3% of the Malaysian population. It is an advantage
that Malaysia halal certification industry is well-developed and recognized as a model all around the world. Malaysia
shows a strong industrial manufacturing potential for a wide range of halal products. The availability of supporting
industries thus provides Malaysia with the ideal conditions to develop into a medical device hub in Asia as well as to
establish a global acceptance model for halal medical devices. This paper will discuss the ethical aspects of developing halal medical devices for the needs of Muslims in Malaysia and other Islamic nations
Chlorophyll fluorescence intensity, photosynthetic yield and flowering in fig fruit trees as affected by phloem stress
HOSSAIN, A. B. M. S., A. SALLEH, M. A. MEKHLED and A. M. Al-SAIF, 2010. Chlorophyll fluorescence intensity, photosynthetic yield and flowering in fig fruit trees as affected by phloem stress. Bulg. J. Agric. Sc., 16: 547-552 Chlorophyll fluorescence intensity, photosynthetic yield in leaves and flowering of fig trees (Ficus carica L.) as affected by phloemic stress (represented by partial bark ring) were studied. The treatments were un-ringed, I-shape partial ring (I-SPR), X-shape partial ring (X-SPR) and S-shape partial ring (S-SPR). The greater bark thickness (width) was found in I SPR treated branch than other treated branches. Branch circumference of all three types of treatment showed higher value in upper ring than in lower ring. The maximum SPAD value was observed in control branch earlier after treatment whereas the maximum value was found in S-SPR treated branch later. Besides, the percent flower bud and fruit set were greater in S-SPR treated trees than other treated branches. The flower bud and fruit set were higher in treated branches than in control. Chlorophyll fluorescence intensity was found similar upward trends with some fluctuations in case of all treatments. The intensity was higher in control and I-SPR treated branches than in other treatments. Fo (lower fluorescence), Fm (higher fluorescence), Fp (Intermediate fluorescence) were highest in leaves of control, I-SPR and X-SPR treated branches. However, X-SPR treatment represented the maximum optimum quantum yield [(Photosynthetic yield (Fv/Fm)]. Resulting, the study represents that phloemic stress (I-SPR, X-SPR & S-SPR), can be applied for the dwarfing physiological growth and early flowering of fig tree and the most effective one was S-SPR
Issues and Challenges in Implementing Outcome Based Education in Engineering Education
In recent years, the implementation of outcome based education (OBE) has been much emphasized in developed and developing nations which led to becoming the focal point for educational reforms. In outcome based education, students are responsible for their own learning and the assessment of learning are based on the outcomes instead of the contents being taught. However, much criticism against the OBE has also been presented in various papers regarding the actual implementation of OBE. In this paper, we discussed the issues and challenges of implementing an outcome based education in engineering education particularly in Faculty of Engineering, UNIMAS, Malaysia
Separation of aromatic and aliphatic hydrocarbons using deep eutectic solvents: A critical review
The reported experimental data for the separation of aromatic from aliphatic compounds using green solvents is growing exponentially. This paper surveys the existing data and presents a critical review that helps clarifying the major findings, identifies shortcomings and provides some recommendations. The comparison between deep eutectic solvents (DESs) and both ionic liquids (ILs) and classical organic solvents for this challenging separation is also presented based on experimental selectivity and distribution ratio data. This comparison confirms the capability of DESs to effectively extract aromatic compounds and shows that DESs can compete with ILs and even outclass them in some cases. Moreover, our comprehensive literature survey has revealed that in many cases the use of DESs yields to a minimum cross-contamination between the two phases. This will undeniably facilitate the separation procedure and thus reduce the cost of the separation process. On the other hand, the performance of COSMO-RS to predict ternary liquid-liquid equilibrium diagrams for systems including DESs is also evaluated in this work for all available data. COSMO-RS was able to reproduce the experimental tie-lines with a good accuracy in many cases. Therefore, it represents a cost-effective and time-saving screening tool to evaluate the extraction performance of the unlimited number of possible salt/complexing agents' combinations
Experimental validation of granular dynamics simulations of gas-fluidised beds with homogeneous inflow conditions using Positron Emission Particle Tracking
A hard-sphere granular dynamics model of a two-dimensional gas-fluidised bed was experimentally validated using Positron Emission Particle Tracking (PEPT). In the model the Newtonian equations of motion are solved for each solid particle while taking into account the particle¿particle and particle¿wall collisions. The gas phase hydrodynamics is described by the spatially averaged Navier¿Stokes equations for two-phase flow. A quasi two-dimensional (i.e. narrow) bed of 0.185-m width and 0.4-m height with homogenous inflow conditions at 1.5 umf was chosen as a test case. Glass particles (¿p=2435 kg/m3) with diameters ranging from 1.25 to 1.5 mm were used as the bed material. The collision parameters required in the simulation were obtained from separate, independent measurements. In the PEPT experiment, the motion of a single tracer particle in the bed was tracked for 1 h. In the simulation, the motion of 15,000 particles was tracked for 45 s. The simulation data were time-averaged over 45 s for each particle and subsequently ensemble-averaged over all the particles in the simulation. The comparison was made on the basis of averaged velocity maps, "occupancy" plots and speed histograms. The results showed good agreement between experiment and simulation when the measured values for the collision parameters were used. When collisions were assumed to be fully elastic and perfectly smooth the agreement was much worse