Search results for: System Model
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13563

Search results for: System Model

3813 A Comparison of First and Second Order Training Algorithms for Artificial Neural Networks

Authors: Syed Muhammad Aqil Burney, Tahseen Ahmed Jilani, C. Ardil

Abstract:

Minimization methods for training feed-forward networks with Backpropagation are compared. Feedforward network training is a special case of functional minimization, where no explicit model of the data is assumed. Therefore due to the high dimensionality of the data, linearization of the training problem through use of orthogonal basis functions is not desirable. The focus is functional minimization on any basis. A number of methods based on local gradient and Hessian matrices are discussed. Modifications of many methods of first and second order training methods are considered. Using share rates data, experimentally it is proved that Conjugate gradient and Quasi Newton?s methods outperformed the Gradient Descent methods. In case of the Levenberg-Marquardt algorithm is of special interest in financial forecasting.

Keywords: Backpropagation algorithm, conjugacy condition, line search, matrix perturbation

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3812 MJPEG Real-Time Transmission in Industrial Environments Using a CBR Channel

Authors: J. Silvestre, L. Almeida, R. Marau, P. Pedreiras

Abstract:

Currently, there are many local area industrial networks that can give guaranteed bandwidth to synchronous traffic, particularly providing CBR channels (Constant Bit Rate), which allow improved bandwidth management. Some of such networks operate over Ethernet, delivering channels with enough capacity, specially with compressors, to integrate multimedia traffic in industrial monitoring and image processing applications with many sources. In these industrial environments where a low latency is an essential requirement, JPEG is an adequate compressing technique but it generates VBR traffic (Variable Bit Rate). Transmitting VBR traffic in CBR channels is inefficient and current solutions to this problem significantly increase the latency or further degrade the quality. In this paper an R(q) model is used which allows on-line calculation of the JPEG quantification factor. We obtained increased quality, a lower requirement for the CBR channel with reduced number of discarded frames along with better use of the channel bandwidth.

Keywords: Industrial Networks, Multimedia.

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3811 The Effect of Nonnormality on CB-SEM and PLS-SEM Path Estimates

Authors: Z. Jannoo, B. W. Yap, N. Auchoybur, M. A. Lazim

Abstract:

The two common approaches to Structural Equation Modeling (SEM) are the Covariance-Based SEM (CB-SEM) and Partial Least Squares SEM (PLS-SEM). There is much debate on the performance of CB-SEM and PLS-SEM for small sample size and when distributions are nonnormal. This study evaluates the performance of CB-SEM and PLS-SEM under normality and nonnormality conditions via a simulation. Monte Carlo Simulation in R programming language was employed to generate data based on the theoretical model with one endogenous and four exogenous variables. Each latent variable has three indicators. For normal distributions, CB-SEM estimates were found to be inaccurate for small sample size while PLS-SEM could produce the path estimates. Meanwhile, for a larger sample size, CB-SEM estimates have lower variability compared to PLS-SEM. Under nonnormality, CB-SEM path estimates were inaccurate for small sample size. However, CB-SEM estimates are more accurate than those of PLS-SEM for sample size of 50 and above. The PLS-SEM estimates are not accurate unless sample size is very large.  

Keywords: CB-SEM, Monte Carlo simulation, Normality conditions, Nonnormality, PLS-SEM.

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3810 Adaptive Algorithm to Predict the QoS of Web Processes and Workflows

Authors: Jorge Cardoso

Abstract:

Workflow Management Systems (WfMS) alloworganizations to streamline and automate business processes and reengineer their structure. One important requirement for this type of system is the management and computation of the Quality of Service(QoS) of processes and workflows. Currently, a range of Web processes and workflow languages exist. Each language can be characterized by the set of patterns they support. Developing andimplementing a suitable and generic algorithm to compute the QoSof processes that have been designed using different languages is a difficult task. This is because some patterns are specific to particular process languages and new patterns may be introduced in future versions of a language. In this paper, we describe an adaptive algorithm implemented to cope with these two problems. The algorithm is called adaptive since it can be dynamically changed as the patterns of a process language also change.

Keywords: quality of service, web processes, workflows, web services

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3809 Relaxation Dynamics of Quantum Emitters Resonantly Coupled to a Localized Surface Plasmon

Authors: Khachatur V. Nerkararyan, Sergey I. Bozhevolnyi

Abstract:

We investigate relaxation dynamics of a quantum dipole emitter (QDE), e.g., a molecule or quantum dot, located near a metal nanoparticle (MNP) exhibiting a dipolar localized surface plasmon (LSP) resonance at the frequency of the QDE radiative transition. It is shown that under the condition of the QDE-MNP characteristic relaxation time being much shorter than that of the QDE in free-space but much longer than the LSP lifetime. It is also shown that energy dissipation in the QDE-MNP system is relatively weak with the probability of the photon emission being about 0.75, a number which, rather surprisingly, does not explicitly depend on the metal absorption characteristics. The degree of entanglement measured by the concurrency takes the maximum value, while the distances between the QDEs and metal ball approximately are equal.

Keywords: Metal nanoparticle, Localized surface plasmon, Quantum dipole emitter, Relaxation dynamics.

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3808 Comparison of BER Performances for Conventional and Non-Conventional Mapping Schemes Used in OFDM

Authors: Riddhi Parmar, Shilpi Gupta, Upena Dalal

Abstract:

Orthogonal Frequency Division Multiplexing (OFDM) is one of the techniques for high speed data rate communication with main consideration for 4G and 5G systems. In OFDM, there are several mapping schemes which provide a way of parallel transmission. In this paper, comparisons of mapping schemes used by some standards have been made and also has been discussed about the performance of the non-conventional modulation technique. The Comparisons of Bit Error Rate (BER) performances for conventional and non-conventional modulation schemes have been done using MATLAB software. Mentioned schemes used in OFDM system can be selected on the basis of the requirement of power or spectrum efficiency and BER analysis.

Keywords: BER, π/4 differential quadrature phase shift keying (Pi/4 DQPSK), OFDM, phase shift keying, quadrature phase shift keying.

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3807 Loan Guarantee Schemes: Private and Public Examples

Authors: Simeon Karafolas, Maciej Woźniak

Abstract:

Guarantee schemes have been introduced in the economic and financial system as response to difficulties of SMEs for the access to the banking credit. Guarantee companies first appeared at the 19e century. Last wave of the development of those schemes appeared at the decade of 1990’s in particular to the new countries members of the EU. Guarantee schemes are presented as public owned guarantee companies, private ones mainly through a mutual form, but also under a mixed form. The paper based on guarantee schemes of five countries tries to investigate the differences that can exist within different guarantee companies. This investigation is based on some indicators that are time of response to the demand of guarantee, threshold of guarantee, acceptance of applications for guarantee, jobs created or saved and bureaucratic issues. It appears that guarantee companies have not the same reaction to the demand of SMEs and some of them are much more active.

Keywords: DIFASS, Guarantees, Loans.

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3806 Packaging Improvement for Unit Cell Vanadium Redox Flow Battery (V-RFB)

Authors: A. C. Khor, M. R. Mohamed, M. H. Sulaiman, M. R. Daud

Abstract:

Packaging for vanadium redox flow battery is one of the key elements for successful implementation of flow battery in the electrical energy storage system. Usually the bulky battery size and low energy densities make this technology not available for mobility application. ThereforeRFB with improved packaging size and energy capacity are highly desirable. This paper focuses on the study of packaging improvement for unit cell V-RFB to the application on Series Hybrid Electric Vehicle. Two different designs of 25cm2 and 100cm2 unit cell V-RFB at same current density are used for the sample in this investigation. Further suggestions on packaging improvement are highlighted.

Keywords: Electric vehicle, Redox flow battery, Packaging, Vanadium.

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3805 Three-Dimensional Positioning Method of Indoor Personnel Based on Millimeter Wave Radar Sensor

Authors: Chao Wang, Zuxue Xia, Wenhai Xia, Rui Wang, Jiayuan Hu, Rui Cheng

Abstract:

Aiming at the application of indoor personnel positioning under smog conditions, this paper proposes a 3D positioning method based on the IWR1443 millimeter wave radar sensor. The problem that millimeter-wave radar cannot effectively form contours in 3D point cloud imaging is solved. The results show that the method can effectively achieve indoor positioning and scene construction, and the maximum positioning error of the system is 0.130 m.

Keywords: indoor positioning, millimeter wave radar, IWR1443 sensor, point cloud imaging

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3804 A Study on Reducing Malicious Replies on the Internet: An Approach by Game Theory

Authors: Sanghun Lee

Abstract:

Since the advent of the information era, the Internet has brought various positive effects in everyday life. Nevertheless, recently, problems and side-effects have been noted. Internet witch-trials and spread of pornography are only a few of these problems.In this study, problems and causes of malicious replies on internet boards were analyzed, using the key ideas of game theory. The study provides a mathematical model for the internet reply game to devise three possible plans that could efficiently counteract malicious replies. Furthermore, seven specific measures that comply with one of the three plans were proposed and evaluated according to the importance and utility of each measure using the orthogonal array survey and SPSS conjoint analysis.The conclusion was that the most effective measure would be forbidding unsigned user access to malicious replies. Also notable was that some analytically proposed measures, when implemented, could backfire and encourage malicious replies.

Keywords: Conjoint Analysis, Game Theory, Internet, MaliciousReplies, Prisoner's Dilemma

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3803 Demographic and Socio-Economic Study of the Elderly Population in Kolkata, India

Authors: Ambika Roy Bardhan

Abstract:

Kolkata, the City of Joy, is a greying metropolis not only in respect of its concrete jungle but also because of the largest population of 60-plus residents that it shelters among all other cities in India. Declining birth and death rates and a negative growth of population indicate that the city has reached the last stage of demographic transition. Thus, the obvious consequence has been the ageing of its population. With this background, the present paper attempts to study the demographic and socio-economic status of the elderly population in Kolkata. Analysis and findings have been based on secondary data obtained from Census of India of various years, Sample Registration System Reports and reports by HelpAge India. Findings show that the elderly population is increasing continuously. With respect to gender, the male elderly outnumbers the female elderly population. The percentage of households having one elderly member is more in the city due to the emergence of the nuclear families and erosion of joint family system. With respect to socio-economic status, those elderly who are the heads of the family are lower in percentages than those in the other age groups. Also, male elderly as head of the family are greater in percentage than female elderly. Elderly in the category of currently married records the highest percentage followed by widowed, never married and lastly, separated or divorced. Male elderly outnumber the female elderly as currently married, while female elderly outnumbers the male elderly in the category of widowed. In terms of living status, the percentage of elderly who are living alone is highest in Kolkata and the reason for staying alone as no support from children also happens to be highest in this city. The literacy rate and higher level of education is higher among the male than female elderly. Higher percentages of female elderly have been found to be with disability. Disability in movement and multiple disabilities have been found to be more common among the elderly population in Kolkata. Percentages of male literate pensioners are highest than other categories. Also, in terms of levels of education male elderly who are graduate and above other than technical degree are the highest receivers of pension. Also, in terms of working status, elderly as non-workers are higher in percentages with the population of elderly females outnumbering the males. The old age dependency ratio in the city is increasing continuously and the ratio is higher among females than male. Thus, it can be stated that Kolkata is witnessing continuous and rapid ageing of its population. Increasing dependency ratio is likely to create pressure on the working population, available civic, social and health amenities. This requires intervention in the form of planning, formulation and implementation of laws, policies, programs and measures to safeguard and improve the conditions of the elderly in Kolkata.

Keywords: Demographic, Elderly, Population, Socio-economic.

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3802 Surviving Abiotic Stress: The Relationship between High Light and High Salt Tolerance

Authors: Rutanachai Thaipratum

Abstract:

The mechanism of abiotic stress tolerance is crucial for plants to survive in harsh condition and the knowledge of this mechanism can be use to solve the problem of declining productivity of plants or crops around the world. However in-depth description is still unclear and it is argued, in particular that there is a relationship between high salinity tolerance and the ability to tolerate high light condition. In this study, Dunaliella salina, which can withstand high salt was used as a model. Chlorophyll fluorometer for nonphotochemical quenching (NPQ) measurement and high-performance liquid chromatography for pigment determination was used. The results show that NPQ value and the amount of pigment were increased along with the levels of salinity. However, it establish a clear relationship between high salt and high light but the further study to optimized the solutions mentioned above is still required.

Keywords: Abiotic stress tolerance, Dunaliella salina, Nonphotochemical quenching, Zeaxanthin.

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3801 Understanding Narrative Transformations of Ebola in Negotiations of Epidemic Risk

Authors: N. W. Paul, M. Banerjee

Abstract:

Discussing the nexus between global health policy and local practices, this article addresses the recent Ebola outbreak as a role model for narrative co-constructions of epidemic risk. We will demonstrate in how far a theory-driven and methodologically rooted analysis of narrativity can help to improve mechanisms of prevention and intervention whenever epidemic risk needs to be addressed locally in order to contribute to global health. Analyzing the narrative transformation of Ebola, we will also address issues of transcultural problem-solving and of normative questions at stake. In this regard, we seek to contribute to a better understanding of a key question of global health and justice as well as to the underlying ethical questions. By highlighting and analyzing the functions of narratives, this paper provides a translational approach to refine our practices by which we address epidemic risk, be it on the national, the transnational or the global scale.

Keywords: Ebola, Epidemic Risk, Medical Ethics, Medical Humanities.

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3800 Evaluation of the Energy Consumption per Bit inBENES Optical Packet Switch

Authors: V. Eramo, E. Miucci, A. Cianfrani, A. Germoni, M. Listanti

Abstract:

We evaluate the average energy consumption per bit in Optical Packet Switches equipped with BENES switching fabric realized in Semiconductor Optical Amplifier (SOA) technology. We also study the impact that the Amplifier Spontaneous Emission (ASE) noise generated by a transmission system has on the power consumption of the BENES switches due to the gain saturation of the SOAs used to realize the switching fabric. As a matter of example for 32×32 switches supporting 64 wavelengths and offered traffic equal to 0,8, the average energy consumption per bit is 2, 34 · 10-1 nJ/bit and increases if ASE noise introduced by the transmission systems is increased.

Keywords: Benes, Amplifier Spontaneous Emission Noise, EnergyConsumption, Optical Packet Switch.

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3799 Plants as Alternative Covers at Contaminated Sites

Authors: M. Grifoni, G. Petruzzelli, M. Barbafieri, I. Rosellini, B. Pezzarossa, F. Pedron

Abstract:

Evapotranspiration (ET) covers are an alternative cover system that utilizes water balance approach to maximize the ET process to reduce the contaminants leaching through the soil profile. Microcosm tests allow to identify in a short time the most suitable plant species to be used as alternative covers, their survival capacity, and simultaneously the transpiration and evaporation rate of the cover in a specific contaminated soil. This work shows the soil characterization and ET results of microcosm tests carried out on two contaminated soils by using Triticum durum and Helianthus annuus species. The data indicated that transpiration was higher than evaporation, supporting the use of plants as alternative cover at this contaminated site.

Keywords: Contaminated sites, ET cover, evapotranspiration, microcosm experiments.

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3798 A Comparison of Shunt Active Power Filter Control Methods under Non-Sinusoidal and Unbalanced Voltage Conditions

Authors: H. Abaali, M. T. Lamchich, M. Raoufi

Abstract:

There are a variety of reference current identification methods, for the shunt active power filter (SAPF), such as the instantaneous active and reactive power, the instantaneous active and reactive current and the synchronous detection method are evaluated and compared under ideal, non sinusoidal and unbalanced voltage conditions. The SAPF performances, for the investigated identification methods, are tested for a non linear load. The simulation results, using Matlab Power System Blockset Toolbox from a complete structure, are presented and discussed.

Keywords: Shunt active power filter, Current perturbation, Non sinusoidal and unbalanced voltage conditions.

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3797 Microgrid: Low Power Network Topology and Control

Authors: Amit Sachan

Abstract:

The network designing and data modeling developments which are the two significant research tasks in direction to tolerate power control of Microgrid concluded using IEC 61850 data models and facilities. The current casing areas of IEC 61580 include infrastructures in substation automation systems, among substations and to DERs. So, for LV microgrid power control, previously using the IEC 61850 amenities to control the smart electrical devices, we have to model those devices as IEC 61850 data models and design a network topology to maintenance all-in-one communiqué amid those devices. In adding, though IEC 61850 assists modeling a portion by open-handed several object models for common functions similar measurement, metering, monitoring…etc., there are motionless certain missing smithereens for building a multiplicity of functions for household appliances like tuning the temperature of an electric heater or refrigerator.

Keywords: IEC 61850, RCMC, HCMC, DER Unit Controller.

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3796 Network Analysis in a Natural Perturbed Ecosystem

Authors: Nelson F.F. Ebecken, Gilberto C. Pereira

Abstract:

The objective of this work is to explicit knowledge on the interactions between the chlorophyll-a and nine meroplankton larvae of epibenthonic fauna. The studied case is the Arraial do Cabo upwelling system, Southeastern of Brazil, which provides different environmental conditions. To assess this information a network approach based in probability estimative was used. Comparisons among the generated graphs are made in the light of different water masses, application of Shannon biodiversity index, and the closeness and betweenness centralities measurements. Our results show the main pattern among different water masses and how the core organisms belonging to the network skeleton are correlated to the main environmental variable. We conclude that the approach of complex networks is a promising tool for environmental diagnostic.

Keywords: Coastal upwelling, Ecological networks, Plankton - interactions, Environmental analysis.

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3795 Assessing the Problems of Pumping Stations: A Case Study of Boneh Basht Pumping Station

Authors: Emad Hazbkhah, Abdolreza Zahiri, Hossein Ghorbanizade Kharazi, Afshin Kiani

Abstract:

Establishing pumping stations is one of the most common ways of providing water from rivers. There are many issues involved in the design and operation of pumping stations most important of which is the problem of sedimentation. One of the significant issues which must be taken into consideration in designing pumping stations is the operation method and technical matters related to it. Safety and convenience of operation is one of the issues that must be always considered by the designer. Some of the major issues in making decisions regarding the type of design for the station are geographical condition, the location of the station and availability of experts in maintenance and operation of the station. Dimensions of the station must allow free movement for checking and operating pumps after installation of pumps and plumbing system.

Keywords: Boneh Basht, Iran, pumping station.

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3794 Parallel-Distributed Software Implementation of Buchberger Algorithm

Authors: Praloy Kumar Biswas, Prof. Dipanwita Roy Chowdhury

Abstract:

Grobner basis calculation forms a key part of computational commutative algebra and many other areas. One important ramification of the theory of Grobner basis provides a means to solve a system of non-linear equations. This is why it has become very important in the areas where the solution of non-linear equations is needed, for instance in algebraic cryptanalysis and coding theory. This paper explores on a parallel-distributed implementation for Grobner basis calculation over GF(2). For doing so Buchberger algorithm is used. OpenMP and MPI-C language constructs have been used to implement the scheme. Some relevant results have been furnished to compare the performances between the standalone and hybrid (parallel-distributed) implementation.

Keywords: Grobner basis, Buchberger Algorithm, Distributed- Parallel Computation, OpenMP, MPI.

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3793 Image Enhancement Algorithm of Photoacoustic Tomography Using Active Contour Filtering

Authors: Prasannakumar Palaniappan, Dong Ho Shin, Chul Gyu Song

Abstract:

The photoacoustic images are obtained from a custom developed linear array photoacoustic tomography system. The biological specimens are imitated by conducting phantom tests in order to retrieve a fully functional photoacoustic image. The acquired image undergoes the active region based contour filtering to remove the noise and accurately segment the object area for further processing. The universal back projection method is used as the image reconstruction algorithm. The active contour filtering is analyzed by evaluating the signal to noise ratio and comparing it with the other filtering methods.

Keywords: Contour filtering, linear array, photoacoustic tomography, universal back projection.

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3792 A Technique for Reachability Graph Generation for the Petri Net Models of Parallel Processes

Authors: Farooq Ahmad, Hejiao Huang, Xiaolong Wang

Abstract:

Reachability graph (RG) generation suffers from the problem of exponential space and time complexity. To alleviate the more critical problem of time complexity, this paper presents the new approach for RG generation for the Petri net (PN) models of parallel processes. Independent RGs for each parallel process in the PN structure are generated in parallel and cross-product of these RGs turns into the exhaustive state space from which the RG of given parallel system is determined. The complexity analysis of the presented algorithm illuminates significant decrease in the time complexity cost of RG generation. The proposed technique is applicable to parallel programs having multiple threads with the synchronization problem.

Keywords: Parallel processes, Petri net, reachability graph, time complexity.

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3791 Design of Bayesian MDS Sampling Plan Based on the Process Capability Index

Authors: Davood Shishebori, Mohammad Saber Fallah Nezhad, Sina Seifi

Abstract:

In this paper, a variable multiple dependent state (MDS) sampling plan is developed based on the process capability index using Bayesian approach. The optimal parameters of the developed sampling plan with respect to constraints related to the risk of consumer and producer are presented. Two comparison studies have been done. First, the methods of double sampling model, sampling plan for resubmitted lots and repetitive group sampling (RGS) plan are elaborated and average sample numbers of the developed MDS plan and other classical methods are compared. A comparison study between the developed MDS plan based on Bayesian approach and the exact probability distribution is carried out.

Keywords: MDS sampling plan, RGS plan, sampling plan for resubmitted lots, process capability index, average sample number, Bayesian approach.

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3790 Searching for an Effective Marketing in the Food Supplement Industry in Japan

Authors: Michiko Miyamoto

Abstract:

The market for "functional foods" and "foods with functional claims" that are effective in maintaining and improving health, has expanded year by year due to the entry of major food and beverage manufacturers following the introduction of the specified health food system in 1991 in Japan. To bring health claims related products or services to the market, it is necessary to let consumers to learn about these products or services; an effective marketing through advertising are important. This research proposes a framework for an effective advertisement medium for the food supplement industry by using survey data of 2,500 people.

Keywords: Functional foods, dietary supplements, marketing strategy, structural equation modeling.

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3789 The Relationship between the Energy of Gravitational Field and the Representative Pseudotensor

Authors: R. I. Khrapko

Abstract:

As is known, the role of the energy-momentum pseudotensors of the gravitational field is to extend the conservation law to the gravitational interaction by taking into account the energy and momentum of the gravitational field. We calculated the contribution of the Einstein pseudotensor to the total mass of a stationary material body and its gravitational field. It turned out that this contribution is positive, despite the fact that the mass-energy of a stationary gravitational field is negative. We concluded that the pseudotensor incorrectly describes the energy of the gravitational field. Nevertheless, this pseudotensor has been used in a large number of scientific works for 100 years. We explain this by the fact that the covariant component of the pseudotensor was regarded as the mass-energy. Besides, we prove the advantage of the covariant energy-momentum conservation law for matter in the Minkowski space-time.

Keywords: Conservation law, covariant integration, gravitation field, isolated system.

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3788 Misleading Node Detection and Response Mechanism in Mobile Ad-Hoc Network

Authors: Earleen Jane Fuentes, Regeene Melarese Lim, Franklin Benjamin Tapia, Alexis Pantola

Abstract:

Mobile Ad-hoc Network (MANET) is an infrastructure-less network of mobile devices, also known as nodes. These nodes heavily rely on each other’s resources such as memory, computing power, and energy. Thus, some nodes may become selective in forwarding packets so as to conserve their resources. These nodes are called misleading nodes. Several reputation-based techniques (e.g. CORE, CONFIDANT, LARS, SORI, OCEAN) and acknowledgment-based techniques (e.g. TWOACK, S-TWOACK, EAACK) have been proposed to detect such nodes. These techniques do not appropriately punish misleading nodes. Hence, this paper addresses the limitations of these techniques using a system called MINDRA.

Keywords: Mobile ad-hoc network, selfish nodes, reputation-based techniques, acknowledgment-based techniques.

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3787 Influence of Channel Depth on the Performance of Wavy Fin Absorber Solar Air Heater

Authors: Abhishek Priyam, Prabha Chand

Abstract:

Channel depth is an important design parameter to be fixed in designing a solar air heater. In this paper, a mathematical model has been developed to study the influence of channel duct on the thermal performance of solar air heaters. The channel depth has been varied from 1.5 cm to 3.5 cm for the mass flow range 0.01 to 0.11 kg/s. Based on first law of thermodynamics, the channel depth of 1.5 cm shows better thermal performance for all the mass flow range. Also, better thermohydraulic performance has been found up to 0.05 kg/s, and beyond this, thermohydraulic efficiency starts decreasing. It has been seen that, with the increase in the mass flow rate, the difference between thermal and thermohydraulic efficiency increases because of the increase in pressure drop. At lower mass flow rate, 0.01 kg/s, the thermal and thermohydraulic efficiencies for respective channel depth remain the same.

Keywords: Channel depth, thermal efficiency, wavy fin, thermohydraulic efficiency.

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3786 A New Maximum Power Point Tracking for Photovoltaic Systems

Authors: Mohamed Azab

Abstract:

In this paper a new maximum power point tracking algorithm for photovoltaic arrays is proposed. The algorithm detects the maximum power point of the PV. The computed maximum power is used as a reference value (set point) of the control system. ON/OFF power controller with hysteresis band is used to control the operation of a Buck chopper such that the PV module always operates at its maximum power computed from the MPPT algorithm. The major difference between the proposed algorithm and other techniques is that the proposed algorithm is used to control directly the power drawn from the PV. The proposed MPPT has several advantages: simplicity, high convergence speed, and independent on PV array characteristics. The algorithm is tested under various operating conditions. The obtained results have proven that the MPP is tracked even under sudden change of irradiation level.

Keywords: Photovoltaic, maximum power point tracking, MPPT.

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3785 Parallel Text Processing: Alignment of Indonesian to Javanese Language

Authors: Aji P. Wibawa, Andrew Nafalski, Neil Murray, Wayan F. Mahmudy

Abstract:

Parallel text alignment is proposed as a way of aligning bahasa Indonesia to words in Javanese. Since the one-to-one word translator does not have the facility to translate pragmatic aspects of Javanese, the parallel text alignment model described uses a phrase pair combination. The algorithm aligns the parallel text automatically from the beginning to the end of each sentence. Even though the results of the phrase pair combination outperform the previous algorithm, it is still inefficient. Recording all possible combinations consume more space in the database and time consuming. The original algorithm is modified by applying the edit distance coefficient to improve the data-storage efficiency. As a result, the data-storage consumption is 90% reduced as well as its learning period (42s).

Keywords: Parallel text alignment, phrase pair combination, edit distance coefficient, Javanese-Indonesian language.

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3784 Navigation and Self Alignment of Inertial Systems using Nonlinear H∞ Filters

Authors: Saman M. Siddiqui, Fang Jiancheng

Abstract:

Micro electromechanical sensors (MEMS) play a vital role along with global positioning devices in navigation of autonomous vehicles .These sensors are low cost ,easily available but depict colored noises and unpredictable discontinuities .Conventional filters like Kalman filters and Sigma point filters are not able to cope with nonwhite noises. This research has utilized H∞ filter in nonlinear frame work both with Kalman filter and Unscented filter for navigation and self alignment of an airborne vehicle. The system is simulated for colored noises and discontinuities and results are compared with not robust nonlinear filters. The results are found 40%-70% more robust against colored noises and discontinuities.

Keywords: filtering, integrated navigation, MEMS, nonlinearfiltering, self alignment

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