250 research outputs found
Effects of chromium powder mixed in electrical discharge machining of AISI D2 hardened steels
Nowadays, electrical discharge machining (EDM) is the non-conventional
method that has been used extensively in machining hard material that is commonly
used in mold and die industry but the limitations of EDM will cause lower productivity
and poor surface quality. EDM becomes most apparent by using powder metallurgy
electrode together with chromium (Cr) powder suspension into the dielectric fluid which
has led to the increasing of productivity and good quality performance and
characteristics. Therefore, by combining of both EDM parameters and machining
conditions by incorporating with specific magnetic system plus integrated with existing
filter system, it is highly expected that the machining speed can be enhanced. However,
there are difficulties to determine the best combination of these machining parameters in
order to increase the material removal rate (MRR) and at the same time to reduce the
electrode wear rate (EWR) with the acceptable surface integrity. This research
emphasizes the studies of Cr powder mixed in EDM machining of AISI D2 hardened
steel using copper tungsten electrode which has been done successfully. Data were
analysed using design of three factors at a time consisted of peak current (Ip), pulse-on
(Pon) and powder concentration(C). Discussions were made on the responses such as
MRR, EWR, Surface Roughness (Ra), surface morphology, recast layer (RL) and
microhardness (MH) on the selected samples from the same machining conditions.
Results have proved that Ip was the most significant parameter which has influenced the
machining responses on Cr powder mixed EDM of AISI D2. It is also found that proper
powder concentration of 2gram/litre enhanced the machining efficiency particularly in
MRR. Furthermore, introduction of proper addition of Cr powder in the dielectric also
decreased Ra and RL thickness. The EWR increased as the peak current increased, but
inversely with pulse-on. In general, the possibility of EDM process for machining AISI
D2 tool steel by incorporating Cr powder mixed in the dielectric is acceptable and the
entire objectives were successfully proven
Proposed new interior design scheme for Pit Stop Camera Sdn Bhd of Canon at S1, Level 2 USJ 19 Subang Jaya Selangor Darul Ehsan / Muhammad Nafis Ridzuan
The final project for the student of Diploma in Interior Architecture is a manifestation towards the student’s knowledge about the whole aspect on interior design that had been learnt from basic to the final presentation on the proposed design. The project that had been chosen for the final project is to propose New Scheme Design Of Pit Stop Centre Camera for Canon Sdn Bhd. This proposed Pit Stop Centre Camera is to attract users, especially all the Canopn users from any race to try for all the latest new products.. The target customer are mostly from government staff, VIP person, family.Concept and image that had been chosen not only must be suitable with the clients as both of it would reflect the client itself, but at the same time it would give a positive impact and to increase the business.Besides, the concept and images itself should be also related with the theme of the Pit Stop Centre Camera. Some of the gained information of the study is through interviews, printed media, internet, observation, and through the result from the case study either locally or internationally
CO2 Capture Using Amino Acid Salt Solution
The concern of climate change and global warming has consecutively risen to progress research fields pledging to find the possible solutions. Increasing use of fossil fuels leads to an increase in CO2 emission and has become a major task to be deal with. For industrial applications, aqueous solutions of amines are extensively used as chemical absorbent or solvent. However, amine reaction with CO2 results in stable carbamate formation, which in turn leads to high energy usage for regeneration and promote additional corrosion problems. To overcome these restrictions, this study proposes a methodology to analyze the performance of new solvent namely amino acid salt solution. Evaluation of solvent performance in terms of CO2 loading and designing of acid gas removal system, requires pressure solubility data and design properties like density, pH value and refractive index
A comparison study of deep CNN models for brain tumor MRI image classification
Throughout the life journey, brain health conditions may emerge and are identified by
disruptions in normal brain growth and brain functioning. One of the disruption that
may manifest as a neurological condition is brain tumor, which incidence is increasing
in recent years. Since manual method of classifying brain tumor images is tedious and
can only be done at certain diagnostic centers, an alternative way of using deep
learning technique to detect abnormal tissues in the brain is undertaken in this work.
In this project, different architectures of Convolutional Neural Network (CNN) models
namely AlexNet, Residual Network-18 (ResNet-18) and GoogLeNet were adopted
and compared for their performance in classification of brain tumor Magnetic
Resonance Imaging (MRI) images via two different approaches namely transfer
learning method and modified method. The performance of the CNN models were
evaluated and the most reliable model for the classification of brain tumor MRI images
was determined. From the comparison done between the transfer learning method and
modified method, transfer learning AlexNet showed the highest accuracy of 87.11%
while modified ResNet-18 demonstrated the lowest accuracy of 76.09%. Based on
observation of this project results and findings from other sources, for both approaches
taken for brain tumor image classification, the tuning of hyperparameters used in
training options (for transfer learning method only), the variation of image data
augmentation to avoid overfitting and the depth of CNN topology influences the
accuracy of the CNN models. The best CNN model for the classification of brain tumor
MRI images with great accuracy was proven to be transfer learning AlexNet model
Optimization of Ethanol Production from Mango Peels using Response Surface Methodology
Environmental concern as well as escalating of fossil fuel price and demanding for renewable energy is the main reasons why bioethanol technology being developed. Bioethanol can act as alternatives energy and reduce dependencies on fossil fuel alone. Recently, research has been done to produce bioethanol by utilization of agricultural waste. Production of bioethanol from mango peels is examples of utilization of agricultural waste. Mango fruit is grown naturally in over 90 countries
worldwide and is known to be the second largest produced tropical fruit crop in the world. This shows that the amount of waste that will produce will be significant. The focal point of this project is to optimize production of bioethanol from mango peels using Response Surface Methodology (RSM) and to studies the effects of temperature, yeast concentration and fermentation time towards production of bioethanol. Mango peels will undergo hydrolysis and fermentation in order to
produce bioethanol. To achieve these objectives, experiment was conducted which consist of four stages; preparation of mango peels, hydrolysis of mango peels,
preparation of yeast and optimization using RSM. The first part of experiment, mango peels is manually peeling off using knife and the underlying pulp was removed. Then, the mango peels is treated with sulphuric acid with concentration of 0.25 % to 1 % (w/v). At acid concentration of 0.25 % (w/v) was the highest amount
of glucose yield. Fermentation is conduct according to experimental design layout that is generated by Design Expert software and the range for temperature, yeast
concentration and fermentation time is 25-40°C, 6-14 g/ml and 48-96 hours respectively. RSM using three factors and two level central composite designs was employed to optimize production of ethanol from mango peels. Based on the results obtained, the concentration of ethanol yield ranged from 5.28-7.34 g/ml. The
optimize condition to produce 7.34 g/ml is 38 °C, 6 g/ml yeast and 48 hours fermentation time. Therefore, this finding portray that the production of ethanol from
mango peels can be scale up for large production industry
ANTECEDENTS TO BUY GREEN PRODUCTS: A CASE OF DEVELOPING COUNTRY
Abstract. The purpose of this paper is to examine the relationship between green perceived value/greenknowledge and intentions to buy green products through green attitude. The research object of this study focuses on Pakistanis consumer. The study undertakes the empirical study and therefore, data are collected through a self-administered questionnaire form 252 respondents. Structural equation modelling technique is used for the analysis of the data with the help of AMOS 22. The empirical results show that green perceived value, green knowledge and green attitude are drivers of intentions to buy green products. Although previous studies have investigated the pertinent issues about green consumer behavior, however, very few studies have been conducted in developing counties like Pakistan. Compared to other developing countries, research on environmental issues in Pakistan is still in the very early stages. This study proposes a research framework which could be helpful for green marketing companies to enhance consumes intentions to buy green products via green perceived value, green knowledge and the green attitude. The empirical results of this study address a serious gap in the existing literature especially in the perspective of an emerging country in the context of green products perception knowledge, attitude and purchase intention. The findings from this study offer significant implications for marketers, academicians as well as policymakers who may concern in promoting extensive promotion and/or adoption of green products.Keywords: green products, green perceived value, green attitude, green knowledge and customer
Understanding the geological basis of the Iowa Pore Index
The Iowa Pore Index test is a method employed by several Midwestern State Departments of Transportation to determine the volume ratio of macropores-to-micropores in a rock aggregate by means of water intrusion. This method, when combined with x-ray diffraction (to measure the dolomite mineral structure using the peak shift) and x-ray fluorescence (to measure the calcite-to-dolomite ratio and the clay content using alumina), has been shown to be effective in predicting the performance of aggregates in Portland cement concrete.
In this test, 4.5 kilograms of oven-dried crushed carbonate is intruded with water progressively at 240 kilopascals. Readings of intruded volume are taken at 1 and 14 minutes corresponding to macropore and micropore volumes, respectively. The Iowa Pore Index test is interesting more broadly because it is fast, non-destructive, inexpensive, and environmentally friendly, hence it has the potential to replace mercury porosimetry and be integrated in any petrophysical lab.
This research aims to understand the geological factors (depositional environment; facies; grain and pore types; texture; and paragenesis) responsible for the results of the Iowa Pore Index test. End-member samples of various geologic ages are collected around Iowa to represent different combinations of accepted and rejected porosity and clay contents. The pore index of each sample is calibrated quantitatively via helium and mercury porosimetry and qualitatively via thin section petrography.
Findings of this research show that even the most homogeneous sources have at least three different rock types, or groups of pebbles characterized by distinctive physical and textural attributes observable at hand-specimen scale. Petrographic analysis shows that limestones with a sparite matrix, peloidal grains, and low matrix-to-allochem ratio (i.e., grainy) are better for road constructions than limestones with a micrite matrix, skeletal grains, and high matrix-to-allochem ratio (i.e., muddy). Dolostones with fine-to-coarse grains, crystal-supported euhedral-to-subhedral rhombs and porous intercrystalline areas are more desirable than dolostones with very fine grains, a tightly interlocking crystal mosaic in anhedral form.
Each rock type occurs in different abundance and has different porosity. Several linear models have been developed to relate IPI to helium porosity. Limestones with a helium porosity less than ~7% and dolostones with a helium porosity greater than ~3% were found to be desirable for use in road construction. The critical range of pore-throat size was found to be between 0.02 to 0.1 õm
Microfluidic Device for Single Cell Impedance Characterization
Detection of single particle has emerged as a noninvasive technique for diagnostic and prognostic patients with cancer suspected. Microfluidic impedance cytometry has been utilized to detect and measure the electrical impedance of single biological particles at high speed. The detailed information of single cells such as cell size, membrane capacitance, and cytoplasm conductivity also can be obtained by impedance measurement over a wide frequency range. In this work, we developed an integrated microneedle microfluidic device to detect and discriminate 9- and 16-μm microbeads. Two microneedles were utilized as measuring electrodes at the half height of the microfluidic device to perform measurement of electrical impedance under a presence of cells at the sensing area. Furthermore, this device was able to distinguish the cell concentration in the suspension fluid. The reusable microneedles were easy to be inserted and withdrawn from the disposable microfluidic. The ultrasonic cleaning machine has been used to clean the reusable microneedle with a simple cleaning process. Despite of the low-cost device, its capability to detect single particles at the sensing area was preserved. Therefore, this device is suitable for cost-efficient medical and food safety screening and testing process in developing countries
Evaluation of Traffic Noise Level in Residential Areas Along Jalan Kluang - Case Study in Sri Gading, Batu Pahat, Johor
Noise, recognized as an adverse factor affecting human health and overall well-being, poses a significant public health concern. This study focuses on evaluating the traffic noise levels in residential areas along Jalan Kluang. Measurements were conducted in four selected residential areas, namely Taman Sri Saga, Taman Cempaka Putih, Kampung Kluang, and Taman Bahagia Baru, during morning (7.30 am - 9.30 am) and evening (4.00 pm - 6.00 pm) peak hours on weekdays. The results indicated that certain locations exceeded the noise limit that set by the Department of Environment (DOE). Kampung Kluang exhibited LAeq values of 71.10 dBA and 71.48 dBA during the morning and evening peak hours, respectively, surpassing the DOE noise limit. Taman Cempaka Putih also recorded noise levels, with LAeq values of 69.40 dBA and 66.46 dBA during the morning and evening peak hours, respectively. In contrast, Taman Sri Saga and Taman Bahagia Baru demonstrated LAeq values still below the DOE limit during both peak hours. Taman Sri Saga recorded LAeq values of 55.63 dBA and 57.78 dBA, while Taman Bahagia Baru recorded LAeq values of 57.58 dBA and 59.65 dBA during the morning and evening peak hours, respectively. Therefore, it is crucial to address the excessive noise levels in the affected residential areas to mitigate the detrimental effects and ensure a healthier living environment for the affected residents in those areas
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