2,126 research outputs found

    Effect Of Emulsification And Blending On The Oxygenation And Substitution Of Diesel Fuel For Compression Ignition Engine

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    Global emission standards are getting more stringent in which the existing diesel engine technologies are on the brink of losing their permit to operate. While there are successful engine side researches that can target the current emission norms, their implementation in existing engines will not be possible due to their higher price tag. With this respect, fuel side improvement with no or minimal modification to engine hardware is the best way to address the issue in the existing engines. The commonly used fuel oxygenators in diesel engines are water, alcohol, biodiesel and the combinations of these. The method of oxygenation and their corresponding results on the combustion, performance and emissions that have been reported in the literatures are widely varied. The current review article targets the blending and emulsification techniques used in the oxygenation and fuel substitution of diesel. Based on the misconceptions about the stability of emulsions, many researchers are found to use the term blending even though the technique they have used is emulsification. While blending of fuels is convenient for fuels which have relatively similar boiling temperature, emulsification technique should be followed for fuel mixtures of varied boiling temperature so that the benefit of micro-explosion can be reflected in the fuel atomization. Secondary atomization resulting from the micro-explosion phenomenon of emulsified fuels and fuel oxygenation are responsible for the improvement of combustion, performance and CO and PM emissions. Latent heat of vaporization is found to be responsible for the reduction of NOx emissions

    Production and characterization of cellulases by Bacillus pumilus EB3

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    Cellulase production from bacteria can be an advantage as the enzyme production rate is normally higher due to bacterial high growth rate. Screening of bacteria, optimisation of fermentation conditions and selection of substrates are important for the successful production of cellulase. This study is conducted to produce cellulase from our local isolate Bacillus pumilus EB3, using carboxymethyl cellulose (CMC) as substrate. Following that, cellulase produced from Bacillus pumilus EB3 was purified using ion exchange chromatography with anion exchanger (HiTrap QXL) for characterisation of the cellulase. Cellulase was successfully produced in 2L stirred tank reactor (STR) with the productivity of 0.53, 3.08 and 1.78 U/L.h and the maximum enzyme activity of 0.011, 0.079 and 0.038 U/mL for FPase, CMCase and β-glucosidase respectively. Purification of cellulase from Bacillus pumilus EB3 using ion exchange chromatography showed that 98.7% of total CMCase was recovered. Protein separation was however based on subtractive separation where the contaminants were bound to the column instead of CMCase. Characterisation of the enzyme found that CMCase from Bacillus pumilus EB3 has a molecular weight range from 30-65 kDa and was optimally active at pH 6.0 and temperature 60℃. The CMCase also retained its activity over a wide pH range (pH 5.0–9.0) and temperature range (30-70℃).Seminar on Engineering and Technology (SET2006), September 4-5, 2006, Putrajaya, Malaysi

    Isolation, Screening and Antibiotic Sensitivity of Pseudomonas species from Kelana Jaya Lake Soil in Selangor Malaysia

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    الكائنات الحية الدقيقة المسببة للأمراض من المستشفى والمجتمعات والبيئة تشكل تهديدات كبيرة لصحة الإنسان أصبح تطوير مقاومة المضادات الحيوية مصدر قلق كبير أيضًا. تهدف هذه الدراسة ، بالتالي ، إلى عزل وفحص وتقييم مدى حساسية المضادات الحيوية لأنواع السودوموناس المعزولة ضد أربعة مضادات حيوية (الجنتاميسين والتتر سيكلين والأمبيسيليلين والبنسلين) على لوحة وسائط مولر-هينتون أغار. عدة. تم استخدام نشر القرص وكذلك اختبار الأكسدة  من نتيجة الأكسدة الإيجابية ، تم التعرف على البكتيريا المعزولة مثلBurkholderia cepacia (97.6% ID),  ، Pseudomonas aeruginosa (99.5 – 99.9% ID),  ، و Pseudomonas fluorescent (75.9% ID).  وقد تبين أن السودوموناس كان عرضة لثلاثة مضادات حيوية فقط (الجنتاميسين ، التتراسيكلين ، والبنسلين) والتي تظهر منطقة تثبيط واضحة بينما كانت الزائفة? مقاومة للأمبيسيلين فقط مع عدم وجود منطقة تثبيط. البكتيريا المعزولة هي مصادر محتملة لتطوير المضادات الحيوية الفعالة ضد البكتيريا المقاومة.   الكلمات المفتاحية: المضادات الحيوية؛ المقاومة البكتيرية. الحساسية ، الزائفةPathogenic microorganisms from hospitals, communities, and the environment remain great threats to human health. The increasing concern about antibiotic resistance has also necessitated the search for robust alternatives. Therefore, this study aims to isolate, screen and evaluate the antibiotic susceptibility of Pseudomonas aeruginosa isolated from a soil sample taken from northern, western and eastern parts of Kelana Jaya Lake against four antibiotics (gentamycin, tetracycline, ampicillin, and penicillin) on a Mueller-Hinton Agar media plate. Pseudomonas identification was done by using API 20 kit. Disc diffusion was employed as well as the oxidase test. From the positive oxidase result, the isolated bacteria were identified as Burkholderia cepacia (97.6% ID), Pseudomonas aeruginosa (99.5-99.9% ID), and Pseudomonas fluorescent (75.9% ID). Only Pseudomonas aeruginosa isolates were further evaluated for antibiotic susceptibility tests. The result showed that P. aeruginosa was susceptible to only three antibiotics (gentamycin, tetracycline, and penicillin) showing a clear zone of inhibition while it was resistant to only ampicillin with no zone of inhibition. Soil isolates are potential sources for the development of effective antibiotics against resistant bacteria.  Keywords: Antibiotics; Bacterial resistance; Sensitivity, Pseudomona

    Effect of soft story on structural response of high rise buildings.

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    Severe structural damage suffered by several modern buildings during recent earthquakes illustrates the importance of avoiding sudden changes in lateral stiffness and strength. Recent earthquakes that occurred have shown that a large number of existing reinforced concrete buildings are vulnerable to damage or even collapse during a strong earthquake. While damage and collapse due to soft story are most often observed in buildings, they can also be developed in other types of structures. The lower level containing the concrete columns behaved as a soft story in that the columns were unable to provide adequate shear resistance during the earthquake. Usually the most economical way of retrofitting such as a building is by adding proper bracing to soft stories. So, in this paper occurring of soft at the lower level of high rise buildings subjected to earthquake has been studied. Also has been tired to investigate on adding of bracing in various arrangements to structure in order to reduce soft story effect on seismic response of building. It is lead to assess the vulnerability level of existing multi-storied buildings so that they can be retrofitted to possess the minimum requirements. This will help in minimizing the impending damages and catastrophes

    Heuristic task scheduling algorithms for optimal resource utilisation in grid computing

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    The demand for high computational power has developed more rapidly in the past few years. The ever-increasing lack of computational resources are less able to satisfy these needs, leading to the development of grid computing. This technology was able to fulfill the increasing demand for computational power, storage capacity, bandwidth availability and resources. Grid computing is considered as a distributed system that utilises resources from multiple geographically distributed computers. This system usually handles workloads that are not interactive and include huge amount of data. The current challenge facing researchers is to determine the optimal task scheduling method that provides optimal resource utilisation in this extremely heterogeneous environment. The main goal of this work is to present an evaluation of resources utilisation for certain heuristic scheduling algorithms in Grid Computing Environment. The results of the two experimental scenarios showed that suf rage algorithm produced the best resource utilisation among the three investigated heuristic scheduling algorithms

    Comparative study for load management of HBase and Cassandra distributed databases in big data

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    The advancement in cloud computing, the increasing size of databases and the emergence of big data have made traditional data management system to be insufficient solution to store and manage such large-scale data. Therefore, there has been an emergence of new mechanisms for data storage that can handle large-scale data. NoSQL databases are used to store and manage large amount of data. They are intended to be open source, distributed and horizontally scalable in order to provide high performance. Scalability is one of the important features of such systems, it means that by increasing the number of nodes, more requests can be served per unit of time. Distribution and scalability are always companied with load management, which provides load balancing of work among multiple nodes. Load management efficiency varies from system to another according to the used load balancing technique. In this study, HBase and Cassandra load management with scalability will be evaluated as they are the most popular NoSQL databases modeled based on Big Table. In particular,this paper will compare and analyze the load management for the distributed performance of HBase and Cassandra using standard benchmark tool named Yahoo! Cloud Serving Benchmark (YCSB). The experiments will measure the performance of database operations with a different number of connections using different numbers of operations, database size, and processing nodes. The experimental results showed that HBase can provide better performance as the number of connections increase in the presence of horizontal scalabilit

    Diagnostic Imaging and Radiation Therapy in the Arab World: A New Model of Advanced Practice

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    This study aimed at suggesting a new model for advanced practice in the diagnostic imaging and radiation therapy in the Arab World by presenting a comparative study between the different medical imaging techniques, the concepts, benefits, risks and medical applications of these techniques has been presented with details. Attempting For building a new model of advanced practice for the diagnostic role of  imaging and radiation therapy in the Arab World; by analyzing the current status of the imaging and radiation therapy in the Arab World, and then surveying the different medical imaging techniques. Then  to suggest a model of best practices upon the outcomes of the study

    Deep Pipeline Architecture for Fast Fractal Color Image Compression Utilizing Inter-Color Correlation

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    Fractal compression technique is a well-known technique that encodes an image by mapping the image into itself and this requires performing a massive and repetitive search. Thus, the encoding time is too long, which is the main problem of the fractal algorithm. To reduce the encoding time, several hardware implementations have been developed. However, they are generally developed for grayscale images, and using them to encode colour images leads to doubling the encoding time 3× at least. Therefore, in this paper, new high-speed hardware architecture is proposed for encoding RGB images in a short time. Unlike the conventional approach of encoding the colour components similarly and individually as a grayscale image, the proposed method encodes two of the colour components by mapping them directly to the most correlated component with a searchless encoding scheme, while the third component is encoded with a search-based scheme. This results in reducing the encoding time and also in increasing the compression rate. The parallel and deep-pipelining approaches have been utilized to improve the processing time significantly. Furthermore, to reduce the memory access to the half, the image is partitioned in such a way that half of the matching operations utilize the same data fetched for processing the other half of the matching operations. Consequently, the proposed architecture can encode a 1024×1024 RGB image within a minimal time of 12.2 ms, and a compression ratio of 46.5. Accordingly, the proposed architecture is further superior to the state-of-the-art architectures.©2022 The Authors. Published by IEEE. This work is licensed under a Creative Commons Attribution 4.0 License. For more information, see https://creativecommons.org/licenses/by/4.0/fi=vertaisarvioitu|en=peerReviewed
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