GSTF Digital Library (GSTF-DL): Open Journal Systems (Global Science and Technology Forum)
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Evaluation of Rice Husks Stabilized Burnt and Unburnt Blocks: Affordable Housing
No full textLow-income families in developing countriesincluding Tanzania experience challenges on owning betterhouses appropriately constructed from locally availablematerials. Houses are either of low standard or low-qualitymaterials. This project examined the use of rice husks, asagricultural wastes substance, in burnt and unburnt blockscommonly used for house construction in Mbeya, Tanzania.Blocks were cast by mixing the natural soil with water and 0, 1, 2,3 or 4 percent rice husks. The cast blocks were air/sun-dried thenhalf of them burnt. Tests performed on the blocks includecompressive strength, flexural strength, relative density andwater absorption. Although it constitutes further study, theefflorescence test were not available when writing this paper.Findings indicated that much as burnt blocks without rice huskshave higher compressive strength compared to unburnt blocks,their water absorption is almost three times of the unburntblocks. Therefore, unburnt blocks could have more potential toresist efflorescence than burnt blocks due to its low waterabsorption. Results also indicates that rice husks slightly increasethe compressive strength of unburnt blocks but are not beneficialon burnt blocks
Groundwater Flow and Its Isotopic Evolution in Deep Aquifer of Jakarta Groundwater Basin
Get PDFJakarta Groundwater Basin is the Quaternary basin and has three zones of the aquifer, where the deepest aquifer is confined aquifer (Aquifer III). Stable isotope 18O and 2H (Deuterium/D) in this research studied to see its evolution, particularly in this deep groundwater. Isotopic evolution is studied to determine the distribution patterns of distribution and factors that may control in the evolution process. The research method was sampling of groundwater from bore wells that tap water from the Aquifer III, and then tested for the content of stable isotope and its TDS. Analyses have been done by using primary data and some secondary data of stable isotope and TDS data. The results showed that the isotopic evolution occurs in the deep aquifer, influenced by the action of water on rock minerals along groundwater flow. In general, isotopic enrichment occurs in line with groundwater flow, where the content of the stable isotope is heavier toward the north. This isotope enrichment related to the isotopic fractionation processes, which may be occur because of the limestone that consists of the aquifer III and Tertiary limestone of Klapanunggal and Bojongmanik Formations. Increasing of TDS in deep groundwater is followed by increasing of the isotope δ18O content, but it is unclear followed by an increasing of δD. Increasing of isotope content of groundwater in the aquifer is influenced by the groundwater flow velocity, where the rapid flow may occurred in the central part of the research area indicated by contours that curve northward, especially on the δ18O distribution contour pattern
Analysis of Linguistic and Discourse Features of the Essays Written for the York English Language Test
No full textThis study builds on the Explanation inference of the Interpretative Argument (Chapelle et al., 2009) and on the work of Cumming et. al (2006) to address the question of whether and how the linguistic and discourse features of essays written in response to the reading-to-write tasks of the York English Language Test (YELT) vary across proficiency levels. For this investigation, a sample of 50 YELT essays, with YELT score between 2 and 7, were analyzed for the features of essay length, lexical sophistication, syntactic complexity, grammatical accuracy, density of interactive and interactional metadiscourse markers, and quality of argument structure. The results showed marked differences across proficiency levels in terms of lexical, syntactic, pragmatic and rhetorical features. In sum, it can be concluded that with the increase in proficiency levels, as depicted by YELT scores, the essays were longer and improved in terms of syntactic complexity, density of interactive and interactional metadiscourse markers, and quality of argument structure
E-Learning through Cloud Computing ServicesProvided by Academic Libraries for PromotingResearch and Development
Get PDFE-learning is a means of becoming literate, involving newmechanisms for communication, such as: computernetworks,multimedia,content portals, search engines, electronic libraries, distancelearning, and web-enabled classrooms. Different web basedapplications such as email, real-time conference, cloud computing,WebCam etc. are being used as important tools in the process of elearning.Cloud Computing is a completely new VirtualInformation and Communication Technology and it is known asthe third revolution after PC and Internet in IT. To be morespecific, Cloud Computing is the improvement of DistributedComputing, Parallel Computing, Grid Computing and DistributedDatabases. The basic principle of Cloud Computing is makingtasks distributed in large numbers of distributed computers. Bycollecting large quantities of information and resources stored inpersonal computers, mobile phones and other equipment, CloudComputing is capable of integrating them and putting them on thepublic cloud for providing required information to the users.LIBRARY is not only a Knowledge Ocean, its main aim is toprovide quality and satisfactory information services for all theusers. In this Digital era, to provide timely updated digitalinformation services and to promote Research and Developments,the Library should improve itself by adopting new technologies.Cloud computing is one of the fastest emerging Digital Informationand Communication Technologies, being applied and used byvarious Libraries and Companies at present. Cloud Computing isthe use of outsourced Digital Information resources which can beaccessed through networking or Internet. Dissemination ofrequired and relevant information to the users of the Library canbe provided easily and regularly through the cloud computingservices. Since Cloud computing offers flexibility in usage andreduces cost, it is very much suitable and accessible for promotingresearch and development. This research paper explains aboutwhat are Cloud Computing, its History, benefits, advantages, andservices. How Cloud computing services can be adopted, variousbest companies of Cloud computing, kinds of services which can beprovided through Cloud computing also have been discussed in thispaper
Experience-based Personalized Diversification of Recommendations
Get PDFAccuracy of the recommendations has long been regarded as the primary quality aspect of Recommender Systems (RS), but there's an increasing cognizance that there are other factors such as diversity that users also value. Despite the increased interest of researchers to improve diversification of recommendations, we find that personalization of diversification has been overlooked. As the preference for diversity changes from person-to-person, we propose a personalized diversification technique which is capable of controlling the trade-off between accuracy and diversity, where personalization is achieved by diversifying the recommendation list with more novel items if the user has shown diverse preferences in the past, and diversifying the recommendation list with more relevant items if the user has shown homogeneous preferences in the past. Moreover, we also introduce a novel recommendation technique which uses the past preferences of a user and the ratings of experienced item category experts in recommendation generation process. As post-filtering approaches generate the final diversified recommendation list by selecting items from a list generated from some RS, we use the recommendation technique we propose in order to generate an initial recommendation list with both novel and relevant items to improve the personalized diversification process. Our experiments and evaluation provides evidence to illustrate the properties of proposed techniques and indicate the proposed approach has comparable results to state-of-art techniques. Moreover, unlike other techniques, our approach can promote both novel and relevant items and also make the diversification process personalized
Human Activity Recognition System Based-on Sequential Logic Circuits and Statistical Models
Get PDFthis research proposed the human activityrecognition system that described complete flow of processes fromlowest process (dealing with images) to highest process (recognizehuman activity). We proposed human action recognition thatmanage image sequence then recognize human action with simplehuman model by model-based recognition technique. Theexperimental result shows good accuracy which up to 93%correctly recognized. We proposed the human activity processwith 3 methods that consecutive improved. All of those methodscan use the result of action recognition as inputs. First method isFSM recognizer. The human model in Finite State Machine (FSM)recognizer can be modeled by rational condition that make it easyto understand and consume low computation cost but it hard todefine complex activity condition so it is unsuitable method forcomplex activity. The second recognizer applied Hidden MarkovModel (HMM) for activity modeling. The HMM recognizer candealing with much more complex activity and give fair recognitionrate. However, HMM recognizer is not involve feature prioritythat should has effect to accuracy so we proposed the thirdrecognizer that used graph similarity measurement for activitymodeling and activity classification. The third one, GraphSimilarity Measurement (GSM) recognizer involved featurepriority for recognition method then show better result thanHMM in most measurement. GSM recognizer has ~84% accuracyin average. FSM recognizer is suitable for simple activity with lowcomputation cost while HMM is suitable for much more complexactivity and use single feature for recognition process. However,HMM method may not give best result for the activity that usemultiple features. GSM is also suitable for complex activity and,furthermore, give better result than HMM for the activity thattrained from multiple features
Anesthetic Activity of Acetylated MS-222 in Tilapia (Oreochromis Niloticus)
Get PDFA group of 8 tilapia (Oreochromis niloticus) were anesthetized once per week for six consecutive weeks, using tricaine methanesulfonate (MS-222) in the water. Time for the fish to reach anesthesia decreased significantly over the first four weeks, and then plateaued at about 27% below the first anesthetic exposure. These results suggest induction of the liver enzymes that convert MS-222 into metabolites, one or more of which have higher anesthetic activity than the parent compound. Major metabolites of MS-222 have been identified as part of regulatory studies evaluating residue persistence in food fishes. One of these metabolites, N-acetyl-3-aminobenzoic acid ethyl ester, which is acetylated MS-222, was selected for testing of anesthetic activity in tilapia. This report shows results of the testing, and speculates as to the potential utility of the acetylated metabolite of MS-222 as an alternate anesthetic agent in fish
Properties of High-Energy Ball-Milled and Hot Pressed Nanocrystalline Tantalum
No full textThe paper describes the process of high-energy ballmilling of tantalum microcrystalline particles aiming at achievinga nanocrystalline material. During intense milling, a reduction ofthe crystallite size occurs, which is the consequence of strongplastic deformation, the introduction of dislocations and theformation of subgrains. Due to the plastic nature of the powders,the particle size increases at the initial stage of milling, wherecold welding and plastic deformation of the particles takes place.Due to the strain hardening, however, the particles crush intosmaller ones. The nanocrystalline powders were hot pressed. Thebulk hot pressed nanocrystalline tantalum have hardness as highas 1067 HV and useful corrosion resistance in chlorideelectrolyte
Effect of Anodizing Medium on The Morphology and Photoluminescent Property of Porous Alumina Film
No full textAnodic alumina films with uniformly distributedself assembled pores of diameters in the nanometric length scalewere prepared by dual step anodization technique inoxalic, phosphoric and sulphuric acid medium. The variationsof pore morphology and photoluminescent properties werestudied with respect to the change in electrolyticmedium. The photoluminescence (PL) spectra of the filmsprepared in different electrolytic medium have been recordedand compared. The PL spectra of the porous anodic alumina(PAA) film prepared in oxalic acid was found to be muchstronger than the PAA prepared in phosphoric and sulphuricacid. However, pore size of the PAA films prepared in oxalicand sulphuric acid were significantly smaller than the PAAfilms prepared in phosphoric acid medium. Presence of oxygendeficient defect centre exerts a strong influence on the PLproperties of the films
A Very Short-Term Energy Forecasting Technique for Small Scale Photovoltaic Systems using k-Nearest Neighbour Algorithm
No full textThe field of photovoltaic (PV) forecasting has beenevolving rapidly in the recent years. This paper provides a veryshort-term forecasting technique on energy harvested from smallscale PV systems. It makes use of a supervised machine learningtechnique, k-nearest neighbours (kNN), to provide PV owners 5easily-comprehensible output levels of Very Low, Low, Medium,High and Very High. This proposed technique uses readilyavailable data from inverters, namely time of the day andinstantaneous power, and data from commonly used additionalweather measurement equipment namely outdoor temperature,panel temperature and on-site irradiance. The proposed techniquetargets very short-term forecasting period of 15 minutes ahead,which is sufficient for building owners to activate alternatives suchas powering up backup generator or switching off non-criticalloads to reduce load demand. The short-term forecasting resultsare useful in small localized areas where the weather changes veryquickly. Its results can be passed to smart energy managementsystem to aid in their decision makings. Historical data of anexisting 30kWp PV system located in Singapore is used to evaluatethe accuracy of the kNN short term forecasting technique. Despitethe lack of expensive and complicated resources such as numericalweather prediction models and satellite and sky imageryobservations of clouds, the proposed technique achieved anacceptable accuracy of over 68%. The paper compares anddiscusses the parameters and the number of neighbours to be usedin the technique