Showing papers in "Indian journal of science and technology in 2013"
TL;DR: This paper compares the two different classification algorithms namely, Naive Bayesian and Decision Tree for predicting 'Crime Category' for different states in USA and showed that, Decision Tree algorithm out performed Naïve Bayesian algorithm and achieved 83.9519% accuracy.
Abstract: Classification is a well-known supervised learning technique in data mining. It is used to extract meaningful information from large datasets and can be effectively used for predicting unknown classes. In this research, classification is applied to a crime dataset to predict 'Crime Category' for different states of the United States of America. The crime dataset used in this research is real in nature, it was collected from socio-economic data from 1990 US Census, law enforcement data from the 1990 US LEMAS survey, and crime data from the 1995 FBI UCR. This paper compares the two different classification algorithms namely, Naive Bayesian and Decision Tree for predicting 'Crime Category' for different states in USA. The results from the experiment showed that, Decision Tree algorithm out performed Naive Bayesian algorithm and achieved 83.9519% Accuracy in predicting 'Crime Category' for different states of USA.
79 citations
TL;DR: In this paper, the authors used the Reynolds equation and boundary conditions were changed for various parameters such as temperature distribution, viscosity variation and radial load to design a bearing with high stiffness, damping characteristic and lubrication inertia.
Abstract: Hydrostatic bearing finds wide application in machine tools with various technologies because of their high stiffness and damping characteristic. The environmental conditions, such as low and/or high temperatures, dust and dirt, moisture and unusual mounting conditions, can also affect a bearing's performance adversely. Therefore, both mechanical and environmental factors may affect the choice of a bearing and its performance. For high speed applications it is necessary to have design data including the effect of rotational lubricant inertia.The objective of the study is to design a hydrostatic bearing with following properties such as high stiffness, damping characteristic and lubrication inertia. In the present study Reynolds equation is used and boundary conditions are changed for various parameters such as temperature distribution, viscosity variation and radial load. The simulated results were analyzed in detail and found that increasing the viscosity of hydrostatic thrust bearing under specific conditions when both surfaces are rotated, the wear and tear are minimized and life time has been increased. This will be of great use in high speed applications.
60 citations
TL;DR: This study reviews the latest released version of the IEEE WAVE standard, reflects the state of art in WAVE technology, and presents the status of each standard in the IEEE 1609 series of standards.
Abstract: Institute of Electrical and Electronics Engineers (IEEE) series of standards for Wireless Access in Vehicular Environment (WAVE) is currently considered as the most promising technology for vehicular networks. It aims to support interoperability and robust safety communications in a vehicular environment. The first trial version of WAVE standard was released in 2006, Most of the published review studies were done on the old trail versions. This study reviews the latest released version of the IEEE WAVE standard, reflects the state of art in WAVE technology, and presents the status of each standard in the IEEE 1609 series of standards. IEEE 1609 series contains four standards that are under development, three are published and one is already withdrawn. Then the study discusses the technical details of IEEE 1609.4 for multi-channel operation and highlights the new features of WAVE Media Access Control (MAC) layer. The study also describes the services and protocols that are provided by IEEE 1609.3 as a network service standard. Frame format that is used in standards are also exposed.
55 citations
TL;DR: In this article, a review of the research trends in WEDM on relation between different process parameters, including pulse on time, pulse off time, servo voltage, peak current, dielectric flow rate, wire speed, wire tension on different process responses include material removal rate (MRR), surface roughness (Ra), sparking gap (Kerf width), wire lag (LAG) and wire wear ration (WWR), and surface integrity factors.
Abstract: Wire-electro discharge machining (WEDM) has become an important non-traditional machining process, as it provides an effective solution for producing components made of difficult-to-machine materials like titanium, zirconium, etc., and intricate shapes, which are not possible by conventional machining methods. Due to large number of process parameters and responses lots of researchers have attempted to model this process. This paper reviews the research trends in WEDM on relation between different process parameters, include pulse on time, pulse off time, servo voltage, peak current, dielectric flow rate, wire speed, wire tension on different process responses include material removal rate (MRR), surface roughness (Ra), sparking gap (Kerf width), wire lag (LAG) and wire wear ration (WWR) and surface integrity factors. Furthermore, different types of WEDM methods introduced and discussed. In addition the paper highlights different modelling and optimization methods and discussed their advantage and disadvantage. The final part of the paper includes some recommendations about the trends for future WEDM researches.
47 citations
TL;DR: The three different and architectures included in this project the bulk of raw data in the optic domain while the implementation of the complex network formation is in the electronic domain, and all the three ringO architectures perform λ monitoring.
Abstract: Wavelength division multiplexing is an accepted technique to exploit the fiber bandwidth in metro network. Designing innovative architectures for metro network often means finding cost effective combinations of electronic and optic technologies and new network paradigms suited for constraints caused by available photonic components and subsystems. The three different and architectures included in this project the bulk of raw data in the optic domain while the implementation of the complex network formation is in the electronic domain. All the three ringO architectures perform λ monitoring. The basic ringO architecture is based on WDM fiber ring. The three ring architectures are designed and simulated using OptSim 5.3 software.
45 citations
TL;DR: The results showed that the days taken to attain maturity was less under elevated temperature of 4°C and 2°C when compared to the ambient temperature, and the accumulated growing degree days were higher under elevated temperatures.
Abstract: At present in the context of climate change, temperature is one of the most important environmental factors influencing the rice crop growth, development, and yield. The duration of each phenological stage is influenced by temperature which has direct impact on yield. The objective of this study is to provide an overview of the influence of elevated temperature on rice phenology and accumulated growing degree days. The experiment was conducted during Kharif 2012 under temperature control chamber, in which temperature is elevated from the ambient level (2°C and 4°C) for the entire crop growth period. The results showed that the days taken to attain maturity was less under elevated temperature of 4°C (96 days) and 2°C (102 days) when compared to the ambient temperature (108 days). The accumulated growing degree days were higher under elevated temperature of 4°C and nearer value for 2°C viz., 1641 and 1583 respectively from that of ambient. Under elevated temperature of 4°C and 2°C, the grain yield was 23 and 13.3 percent less from the ambient. The highest grain yield is from the treatment under ambient temperature with 6.2 t/ha followed by 5.3t/ha under 2oC level and 4.7 t/ha at 4oC level. The yield loss under elevated temperature is due to the sterile florets and lesser crop duration.
41 citations
TL;DR: In this paper, the effect of PMD in optical fiber in one hindered km link fiber was analyzed and an optical compensation technique was proposed to reduce PMD effect in single mode fiber.
Abstract: The maximum channel density for digital transmission can be achieved by increase the bit rate. When the bit rate cross the 2.5Gbps , the PMD degrade the transmission characteristics. PMD occurs in single mode fiber and because of PMD it impossible to transmit data reliability at high speed. This effects results the widening the pulses and reduce the capacity of transmission of the fiber. This work analyzes the effect of PMD in optical fiber in one hindered km link fiber. The eye diagram, Q value and bit rate for analyzing the PMD. Also an optical compensation technique by which the effect of PMD can be reduced is also analyzed. bit error rate can be achieved by simulating with OptSim 5.3, which includes the algorithms to guarantee the maximum possible accuracy and correct results.
41 citations
TL;DR: In this article, the authors proposed a novel framework called phishing dynamic evolving neural fuzzy framework (PDENF), which adapts the evolving connectionist system (ECoS) based on a hybrid (supervised/unsupervised) learning approach.
Abstract: Phishing is a kind of attack in which criminals use spoofed emails and fraudulent web sites to trick financial organization and customers. Criminals try to lure online users by convincing them to reveal the username, passwords, credit card number and updating account information or fill billing information. One of the main problems of phishing email detection is the unknown “zero-day” phishing attack, (we define zero-day attacks as attacks that phisher mount using hosts that do not appear in blacklists and not trained on the old data sample and it is a noise data), which increases the level of difficulty to detect phishing email. Nowadays, phishers are creating different representation techniques to create unknown “zero-day” phishing email to breach the defenses of those detectors. Our proposed is a novel framework called phishing dynamic evolving neural fuzzy framework (PDENF), which adapts the evolving connectionist system (ECoS) based on a hybrid (supervised/unsupervised) learning approach. PDENF adaptive online is enhanced by offline learning to detect dynamically the phishing email included unknown zero-day phishing e-mails before it get to user account. PDENF is suggested to work for high-speed “life-long” learning with low memory footprint and minimizes the complexity of the rule base and configuration with few number of rules creation for email classification. We expect to achieves high performance, including high level of true positive, true negative, sensitivity, precision, F-measure and overall accuracy compared with other approaches.
38 citations
TL;DR: In this paper, the effect of addition of magnetic water on workability, strength and mechanical properties of concrete tested show-encouraging results, and one can easily replace normal water with magnetic water by which quantity of cement used in any concrete mix reduces and can be made as new Eco-friendly construction material for future decades.
Abstract: It is expected that in the near future, the civil engineering community will have to produce structures in harmony with the concept of sustainable development through the use of high-performance materials with low environmental impact that are produced at a reasonable cost. Magnetic water concrete, synthesized from the normal materials used for manufacturing of concrete, provides one route towards this objective. This paper presents the effect of addition of magnetic water on workability, strength and mechanical properties of concrete tested show-encouraging results, and one can easily replace normal water with magnetic water by which quantity of cement used in any concrete mix reduces and can be made as new Eco-friendly construction material for future decades.
38 citations
TL;DR: The hybrid WDM/TDM PON based Ladder network is simulated and the transmission characteristics evaluated and the reuse of existing optical fiber cable networks allows the introduction of duplicate routes for the shared portions of PONs by using a few optical fiber cables with simple structures.
Abstract: Fiber-To-The-Home [FTTH] is an alternate technology for broadband access networks. Passive optical network (PON) is considered the most promising solution due to the relatively low deployment cost. Current time division multiplexing [TDM] PON architectures are economically feasible, are band limited. The WDM PONs currently available offers enough bandwidth for the present and also for future multimedia broadband services. The purpose of this paper is to simulate resilient access network architecture with a cable route protection function based on hybrid wavelength division multiplexing and time division multiplexing passive optical network (WDM/TDM-PON) systems. Hybrid WDM-TDM PON combines the advanced features of both TDM PON and WDM PON. The reuse of existing optical fiber cable networks allows the introduction of duplicate routes for the shared portions of PONs by using a few optical fiber cables with simple structures. In this work, the hybrid WDM/TDM PON based Ladder network is simulated and the transmission characteristics evaluated. Simulation is done by using Optsim ver.5.3.
38 citations
TL;DR: The design and development of a DC-DC Converter using a two stage buck-boost operation is discussed and by a suitable controller and galvanic isolation, the ripple magnitude in the output is reduced considerably.
Abstract: In this work, the design and development of a DC-DC Converter using a two stage buck-boost operation is discussed. This converter is suitable for low power application such as a matrix LED lighting system. The advantage of this converter is that instead of using two controlled switches as in case of a conventional converter, this circuit uses one MOSFET as a switch. The circuit uses two inductors and two capacitors as energy transferring elements that are able to provide a good quality, high efficiency power supply to the load. The design of TSBB converter is analyzed with closed loop control using a PI controller circuit. Even with smaller values of inductor and capacitor a highly efficient power supply can be made. The main feature of this circuit compared to the other circuits proposed previously is that have a galvanic isolation between the load and the source is provided. Thus, by a suitable controller and galvanic isolation, the ripple magnitude in the output is reduced considerably. A simulation model of the TSBB converter with results is presented.
TL;DR: In this article, two types of organic montmorillonite nanoclay (N3 and N4) were chosen to blend with 80/100 base asphalt in various concentrations (3, 7% and 9%) by weight of the asphalt and subjected to aging using the Rolling Thin Film Oven in order to simulate short term aging.
Abstract: In order to increase the life of bituminous pavement, quality of bitumen needs to be enhanced and modified. The objective of this study was to evaluate the conventional and rheological properties of binders containing various percentages of organic montmorillonite nanoclay particles before and after a short-term aging process. Two types of organic montmorillonite nanoclay (N3 and N4) were chosen to blend with 80/100 base asphalt in various concentrations (3%, 7% and 9%) by weight of the asphalt and subjected to aging using the Rolling Thin Film Oven in order to simulate short term aging. The conventional properties of organic montmorillonite nanoclay modified bituminous binders before and after aging were characterized using retained penetration, increment in softening point, and viscosity aging index concepts while the rheological properties were characterized in terms of their complex shear modulus, phase angle, overall resistance to deformation, and their viscoelastic behavior were measured at higher temperatures ranging from 40 to 82°C using Dynamic Shear Rheometer. The test results showed that the introducing of organic montmorillonite nanoclay to the asphalt binder improves the aging effect on the conventional and fundamental properties as compared to unaged modified asphalt. This improvement can recognized through the higher retained penetration and lower increment in softening point as well as viscosity aging index. Also, the result showed remarkable improvement in rutting resistance of the aged modified binder which results in better resistance to permanent deformation at intermediate and high temperature. Compared between the two types of nanoclay, N3 showed better enhancement to the conventional and rheological properties of asphalt binders and exhibited greater resistance to rutting before and after aging process, which can be contributed to the better dispersion of clay layers of N3 inside asphalt binder that refer to the types of surface treatment of the montmorillonite nanoclay.
TL;DR: In this article, the effect of chromatic dispersion in an optical fiber link was analyzed using simulation using fiber Bragg grating by varying its grating period and linear chirp coefficient.
Abstract: Chromatic dispersion is a critical factor that limits the quality of transmitted optical signal in high speed fiber optic communication systems Chromatic dispersion occurs due to the propagation delay spread of different spectral components of the transmitted signal This leads to the pulse broadening of transmitted signal In order to operate the fiber optic communication system with a sufficiently low bit error rate and to minimize the performance degradation caused by pulse distortion and broadening, dispersion compensation is needed The purpose of this project is to compensate the chromatic dispersion using fiber Bragg grating and optical phase conjugation techniques Simulation results will be obtained using OPTSIM software version 53 Effect of chromatic dispersion in an optical fiber link was analyzed Simulation using Fiber Bragg grating by varying its grating period and linear chirp coefficient was obtained
TL;DR: The objective is to propose appropriate programming paradigms for loosely coupled distributed and object-oriented systems with a specific focus on parallel programming and client-server object computing.
Abstract: Implementing a distributed process using object oriented programming is challenging especially for clusters of nodes ensuring the availability. Java happens to be well suited for writing object oriented programs for applications which needs modularity and high degree of cohesion [2]. In this paper our objective is to propose appropriate programming paradigms for loosely coupled distributed and object-oriented systems with a specific focus on parallel programming and client-server object computing. We select a prototype tool made based on the research outcome as found in [1] for this purpose. This research prototype tool 'Vishwa' provides a very good starting point for graduate students, engineers and scientists in academia, industry and government to present their tasks using the aspects of parallel and distributed computing. The learning curve is shorter in the domain of grid due to the simplicity in deploying and processing with this tool. We also demonstrate with a case study for bringing out the easiness in splitting the given job into subtasks and executed in this type of grid environment.
TL;DR: This work surveyed on several existing cloud storage frameworks, techniques and their advantages, drawbacks and also discusses the challenges that are required to implement secure cloud data storage.
Abstract: Cloud Computing is an environment for providing information and resources that are delivered as a service to end-users over the Internet on demand. Thus cloud enables users to access their data from any geographical locations at any time and also has brought benefits in the form of online storage services. Cloud storage service avoids the cost expensive on software, personnel maintenance and provides better performance, less storage cost and scalability. But the maintenance of stored data in a secure manner is not an easy task in cloud environment and especially that stored data may not be completely trustworthy. Cloud delivers services through internet which increases their exposure to storage security vulnerabilities. However security is one of the major drawbacks that preventing several large organizations to enter into cloud computing environment. This work surveyed on several existing cloud storage frameworks, techniques and their advantages, drawbacks and also discusses the challenges that are required to implement secure cloud data storage. This survey results help to identify the future research areas and methods for improving the existing drawbacks.
TL;DR: In this article, the thermal properties of doped Azopolyester were obtained by solution casting technique and the thermal stability theories proposed by O'Dwyer, TGA analysis, and measurements were discussed.
Abstract: The thermal properties of doped Azopolyester were obtained by solution casting technique. Many theories have been suggested by various thermal stability mechanisms in organic solids. Since the polymers of the present study behave like semiconductors, these theories may be extended to explain thermal stability. In this section, the thermal stability theories proposed by O'Dwyer, TGA analysis, and measurements were discussed. The thermal stability properties reveal that the conductivity is appreciable in the temperature ranging from 30°C to 70°C (303 to 343K) and when it is more than 70°C (343 K) the conductivity is drastically reduced and polymeric blends undergo a gradual weight loss in the temperature ranging from 400-800°C due to attributed loss of volatile solvents trapped in the polymer. These studies are done with the help of O'Dwyer basic theory of thermal stability.
TL;DR: The aim of this research is the development and analysis of digital signal processing techniques for enhancing performance in coherent optical communication systems by tailoring modulation and DSP post-processing algorithms to the optical.
Abstract: The aim of this research is the development and analysis of digital signal processing techniques for enhancing performance in coherent optical communication systems. While much of the current digital techniques are identical to those found in the digital wireless literature, we will investigate improvements in performance to be obtained by tailoring modulation and DSP post-processing algorithms to the optical. The combination of polarization-multiplexing and quadrature phase shift-keying (PM-QPSK or DP-QPSK) is emerging as one the most promising solutions to reach bit rates of 100 Gbps and higher. At the receiver end, the use of digital signal processing (DSP) [1, 2] results in significant deployment improvement over the traditional implementation. This application note shows a practical design of a 100 Gbps DP-QPSK transmission system using coherent detection with digital signal processing for distortion compensation.
TL;DR: In this article, the authors investigated the simultaneous use of nano-SiO 2 and silica fume in concrete and found that using both materials improves the qualities of concrete and achieved a 42.2% increase in compressive strength in comparison to control sample.
Abstract: The use of silica fume has been considered as a pozzolan for several years. Besides, doing research about nano and its application in concrete is increasing. The present study investigates the simultaneous use of nano-SiO 2 and silica fume in concrete. In order to such a purpose, silica fume in measures of 5 and 10 percent and nano-SiO 2 in measures of 0.5 and 1 percent were replaced with cement and totally eight mixture plans for doing the compressive strength and water absorption experiments. Finally, the results showed that using such materials improves the qualities of concrete. Using both 10% silica fume and 1% nano SiO 2 , as a cement replacement, resulted in 42.2% increase in compressive strength in comparison to control sample. Furthermore, it was understood that the simultaneous use of these materials is more influential than their single use.
TL;DR: In this article, the authors identify and analyse the urban sprawl of Tripoli as a pattern and as process, also to understand and assess the interchangeable relationship of urban growth and population growth of study area.
Abstract: The remote sensing data and GIS have been used widely to analyse and study the patterns of urban expansions. The capital of Libya, Tripoli was selected to perform this study and to examine its urban growth. Four satellite imageries and population censuses of the study area for the time period 1984 to 2010 were used in this work. The objectives of this paper are identifying and analysing the urban sprawl of Tripoli as a pattern and as process. Also to understand and assess the interchangeable relationship of urban growth and population growth of study area. Urban area extents in different time periods were extracted by supervised classification method of the satellite imageries. Then, the population data and urban extents data were coupled to perform the analysis. Additionally, Shannon's entropy technique was used for further assessment of urban growth. The study findings demonstrate that Tripoli had sprawled urban growth during the period 1984 to 2010. Moreover, during the above mentioned period, the urban expansion dispersion rate has shown in an ascending mode. Consequently, this uncontrolled dispersed urban development had resulted in high consumption land rate per capita despite of decrement in population growth rate.
TL;DR: The notion of intuitionistic fuzzy soft groups is introduced and ( λ, θ )-level set, union and intersection of them are studied and definition of direct product of intuitionism fuzzy soft group under soft function is defined.
Abstract: This article concerns the relationship between intuitionistic fuzzy soft sets and groups. In this paper, the notion of intuitionistic fuzzy soft groups is introduced and ( λ, θ )-level set, union and intersection of them are studied. Furthermore, definition of direct product of intuitionistic fuzzy soft group under soft function is defined.
TL;DR: From the result of testing the system, it successfully recognizes the specific user’s voice and rejected other users’ voice, which is a medium range of the security level system.
Abstract: A voice recognition system is designed to identify an administrator voice. By using MATLAB software for coding the voice recognition, the administrator voice can be authenticated. The key is to convert the speech waveform to a type of parametric representation for further analysis and processing. A wide range of possibilities exist for parametrically representing the speech signal for the voice recognition system such as Mel-Frequency Cepstrum Coefficients (MFCC). The input voice signal is recorded and computer will compare the signal with the signal that is stored in the database by using MFCC method. The voice based biometric system is based on single word recognition. An administrator utters the password once in the training session so as to train and stored. In testing session the users can utter the password again in order to achieve recognition if there is a match. By using MATLAB simulation, the output can obtain either the user is being recognized or rejected. From the result of testing the system, it successfully recognizes the specific user’s voice and rejected other users’ voice. In conclusion, the accuracy of the whole system is successfully recognizing the user’s voice. It is a medium range of the security level system.
TL;DR: At present, the researchers are trying to develop mathematical and computer models, which not only provide a more exact simulation but enable studies to be carried out on stability or response, comfort and optimization of the design characteristics of various components of the vehicle system.
Abstract: In India Automobiles provide a vital infrastructure for the growth of industry and agriculture. Human civilization has inevitably relied on substantial movement of passengers and goods in a speedy manner and the volume of this has gone up enormously with massive rise in population and economic activity. The demand of higher operating speeds, greater axle loads, better riding comfort and more running safety has attracted the attention of professional talents to give a serious thought to the problem of vehicle system dynamics and to devise ways and means to achieve the above requirements through effective methods. At present, the researchers are trying to develop mathematical and computer models, which not only provide a more exact simulation but enable studies to be carried out on stability or response, comfort and optimization of the design characteristics of various components of the vehicle system. Vehicle dynamics, stability deals with the study of vehicle in motion under the action of various forces. Any vehicle comprises of linear as well as angular movements along and about the three mutually perpendicular coordinate directions x, y, z. The linear movements are longitudinal, lateral and vertical displacements and the angular movements are rolling, pitching and yawing respectively for x, y, z directions.
TL;DR: This work considers the dataset with multi classes and proposes the classification for each location of protein subcellular in a separate layer to achieve high efficiency and improve the prediction and classification accuracy.
Abstract: Subcellular localization is a well-designed representation of proteins. We need a fully automatic and reliable prediction system for protein subcellular localization, especially for the analysis of large-scale of yeast microarray data. In this paper we consider the dataset with multi classes and propose the classification for each location of protein subcellular in a separate layer. In this work, a multi-classification approach for subcellular localization is designed and developed to achieve high efficiency and improve the prediction and classification accuracy. The rule based Ripper method has been found to predict the subcellular localization of proteins from their protein microarray data, compared to other classifiers.
TL;DR: In this article, the efficiency of various vegetable oil-based cutting fluids based on some process parameters such as thrust force, temperature developed at the tool chip interface and flank wear during machining of some non-ferrous metals using different tool materials were highlighted.
Abstract: In the beginning, cutting fluids consisted of simple oils applied with brushes to cool and lubricate the machine tool. However, cutting fluid formulation became more complex as cutting operations became more severe. There are several types of cutting fluids nowadays and the most common can be categorized into cutting oils or water-miscible fluids. In this paper, attention is focused on recent research work on the application of vegetable oil-based cutting fluids in machining non-ferrous metals. The efficiency of various vegetable oil-based cutting fluids based on some process parameters such as thrust force, temperature developed at the tool chip interface and flank wear during machining of some non-ferrous metals using different tool materials were highlighted. The results obtained established vegetable oil-based cutting fluids as a good metalworking fluid.
TL;DR: People who have citizenship of India and whose age is above 18 years and of any sex can give their vote through online without going to any physical polling station and this will increase the voting percentage in India.
Abstract: Internet voting systems have gained popularity and have been used for government elections and referendums in the United Kingdom, Estonia and Switzerland as well as municipal elections in Canada and party primary elections in the United States. Voting system can involve transmission of ballots and votes via private computer networks or the Internet. Electronic voting technology can speed the counting of ballots and can provide improved accessibility for disabled voters. The aim of this paper is to people who have citizenship of India and whose age is above 18 years and of any sex can give their vote through online without going to any physical polling station. Election Commission Officer (Election Commission Officer who will verify whether registered user and candidates are authentic or not) to participate in online voting. This online voting system is highly secured, and its design is very simple, ease of use and also reliable. The proposed software is developed and tested to work on Ethernet and allows online voting. It also creates and manages voting and an election detail as all the users must login by user name and password and click on his favorable candidates to register vote. This will increase the voting percentage in India. By applying high security it will reduce false votes.
TL;DR: In this article, the effectiveness of Van Hiele's phase-based learning on students' levels of geometric thinking was evaluated in a six-week study with 94 students and two teachers.
Abstract: The purpose of this study was to test the effectiveness of Van Hiele's phase-based learning on students' levels of geometric thinking. Quasi-experimental design was used in this study. The six-week study was conducted in a secondary school involving 94 students and two teachers. The students were divided into two groups, with 47 in a control group and the other 47 in a treatment group. Van Hiele's Geometry Test (VHGT) was given to both groups before and after the treatment. Ten students were randomly selected to further determine their initial and final levels of geometric thinking. Wilcoxon-t tests were conducted to test the developed hypotheses. The results showed that there was no significant difference between the initial levels of geometric thinking in both groups. However, the analysis showed significant difference between the final levels of geometric thinking in both groups. Furthermore, qualitative analysis revealed that, in initial levels of geometric thinking, the majority of students in both groups obtained the first Van Hiele levels with complete acquisition, a low acquisition of level two and no acquisition of level three. In the post interview, most of the students in the control group showed an increment of geometric thinking from level one to level two, but no one in this group achieved level three. In contrast, all the students in the treatment group showed a complete acquisition of Van Hiele level one and almost all of them indicated a complete acquisition of level two. As for level three, only one student did not achieve this level, whereas the rest showed a complete and high level of acquisition. This demonstrates that Van Hiele's phase-based learning can be applied in classrooms in order to help students achieve better level of geometric thinking.
TL;DR: In this paper, a laboratory study was undertaken to determine the N release pattern of Urea Intercalated Biochar derived from Prosopis juliflora, which is a potential substrate that can be exploited to develop slow release N fertilizer with higher use efficiency and less environmental harzard.
Abstract: A laboratory study was undertaken to determine the N release pattern of Urea Intercalated Biochar derived from Prosopis juliflora. Biochar was produced by pyrolysing the wood cuttings excluding the bark at 350°C. The resultant biochar was characterized using XRD, FT-IR, Raman Spectroscopy and SEM. After characterization, different forms of nitrogen viz., NH 4 + , NO 3 − , NH 2 , Combined NH 4 + and NO 3 − were loaded at varying concentrations (20-200 mM) and sorption and desorption characteristics were examined. Among the forms tested, urea fortified with biochar showed lower desorption at levels of N loading concentration. A new biochar based formulation was evolved by intercalating biochar with urea at 1:1 ratio through hydrothermal method. The intercalated urea: biochar (1:1 ratio) fertilizer was characterised using the set of equipments and the total nitrogen was quantified as 30% as per the EDAX values which closely coincided with analytical values. The retention and release pattern of urea intercalated biochar depicts that the biochar derived PJ is a potential substrate that can be exploited to develop slow release N fertilizer with higher use efficiency and less environmental harzard.
TL;DR: An unequal clustering approach in the networks for even energy distribution is proposed which reduces the overall energy consumption which in turn improves the network lifetime.
Abstract: Energy efficient modeling is a major issue in the wireless sensor network. The main solution for energy efficient routing is by means of clustering. This paper proposes an unequal clustering approach in the networks for even energy distribution. It also reduces the overall energy consumption which in turn improves the network lifetime. The simulation is carried out in MATLABR2010a. The energy needed for entire operations for one round using the proposed method is lesser than that of LEACH, an equal clustering methodology.
TL;DR: This paper analyses and discusses various methods like adopting cryptographic methods, writing access rights and policies, anonymising data, segregating or fragmenting and then reconstructing the data, etc to preserve the privacy of user and data and while performing public auditing on the cloud data.
Abstract: Cloud Computing is continuously evolving and showing consistent growth in the field of computing. But, the security issues and threats associated with it still stay as a cumbersome. The focal point of this paper is Privacy preserving in cloud computing. This paper analyses and discusses various methods like adopting cryptographic methods, writing access rights and policies, anonymising data, segregating or fragmenting and then reconstructing the data, etc. All these approaches would preserve the privacy of user and data and while performing public auditing on the cloud data. The surveyed approaches are showcased and compared with one another, stating their pros and cons. Finally, the results are centralized and the issues to be concentrated in the future are drawn out. Enabling complete user control over his data, anonymising or encrypting the sensitive data before outsourcing, notifying the data owner upon data access, altogether with the tied up security mechanisms would nullify the privacy issue. This would serve as a helping note in the progress of strengthening the privacy preserving approaches in Cloud Computing.
TL;DR: A modified version PKM protocol for both unilateral and mutual authentication, which is termed as Self-organized Efficient Authentication and Key Management Scheme (SEAKS) authentication protocol is proposed to ensure secure end-to-end data transmission using distributed hop-by-hop authentication and localized key management schemes.
Abstract: Mobile Multihop Relay (MMR) network is one of the emerging technologies, especially LTE-Advanced, WiMAX and the Smart grid communications. Ensuring security is one of the most imperative and challenging issues in MMR networks. Privacy Key Management (PKM) protocol is proposed to ensure the security measures in MMR networks. However, the protocol still faces several security threats, specifically Denial of Service (DoS), replay attacks, Man in the Middle (MitM) attacks and the interleaving attacks, which is termed as Medium Access Control (MAC) layer attacks. This paper proposed a modified version PKM protocol for both unilateral and mutual authentication, which is termed as Self-organized Efficient Authentication and Key Management Scheme (SEAKS) authentication protocol. This protocol ensures secure end-to-end data transmission using distributed hop-by-hop authentication and localized key management schemes with a very simple and efficient way. The performance evaluation of the proposed schemes in terms of packet delivery ratio, packet overhead, processing time and the effect of increasing number of rogue relay stations is carried out and compared with the official draft of MMR WiMAX and the SEN XU. The result showed that our proposed scheme out-performed the base line protocols.