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How much can we trust high-resolution spectroscopic stellar chemical abundances?
To study stellar populations, it is common to combine chemical abundances from different spectroscopic surveys/studies where different setups were used. These inhomogeneities can lead us to inaccurate scientific conclusions. In this work, we studied one aspect of the problem: When deriving chemical abundances from high-resolution stellar spectra, what differences originate from the use of different radiative transfer codes? 2016 Proceedings of the 12th Scientific Meeting of the Spanish Astronomical Society - Highlights of Spanish Astrophysics IX, SEA 2016. All rights reserved. -
Demand response for residential loads using artificial bee colony algorithm to minimize energy cost
Power performance expectations are increasing, impacting designs and requiring advanced technology to improve system reliability. Demand Response (DR) is a highly flexible customer driven program in which customer voluntarily changes his energy usage patterns during the peak demand to maintain the system stability and reliability and thereby improves the performance of the gird. This paper proposes a novel algorithm for optimization of the DR schedule of the residential loads for various hours of the day using Artificial Bee Colony (ABC) algorithm. Here, the objective function is subjected to the constraints like cost constraints, time constraints and load demand. The results show that the proposed approach enhances potential in solving problems with good reliability compared with existing approaches. 2015 IEEE. -
Microhardness studies of vapour grown tin (II) sulfide single crystals
Earth abundant tin sulfide (SnS) has attracted considerable attention as a possible absorber material for low-cost solar cells due to its favourable optoelectronic properties. Single crystals of SnS were grown by physical vapour deposition (PVD) technique. Microindentation studies were carried out on the cleaved surfaces of the crystals to understand their mechanical behaviour. Microhardness increased initially with the load, giving sharp maximum at 15 g. Quenching effect has increased the microhardness, while annealing reduced the microhardness of grown crystals. The hardness values of as-grown, annealed and quenched samples at 15 g load are computed to be 99.69, 44.52 and 106.29 kg/mm 2 respectively. The microhardness of PVD grown crystals are high compared to CdTe, a leading low-cost PV material. The as-grown faces are found to be fracture resistant. 2015 AIP Publishing LLC. -
A mobile based remote user authentication scheme without verifier table for cloud based services
The emerging Cloud computing technology, offering computing resources as a service is gaining increasing attention of both the public and private sector. For the whole hearted adoption of Cloud, the service providers need to ensure that only valid users gain access to the services and data residing within the provider's premises. Ensuring secure access to sensitive resources within the Cloud requires a strong user authentication mechanism using multiple authentication factors. The mechanisms should also consider the increasing needs of Internet access through smart phones and other mobile devices and facilitate access through a variety of devices. Traditionally, a user needs to maintain separate user accounts for each Service Provider whose service he/she desires to use and this may cause inconvenience to users. Single Sign on (SSO) addresses this issue by permitting users to create one login credential and access multiple services hosted in different domains. In this scenario, a compromise of the single credential can result in account take over at many other sites. This points out to the requirement of strengthening the authentication mechanism by using more than one factor. This paper proposes a SSO based remote user authentication scheme for a Cloud environment. The proposed protocol uses password and mobile token and does not require the server to maintain a verifier table. The protocol is verified using automated security Protocol verification tool, Scyther and the results prove that the protocol provides protection against man-in-the-middle attack, replay attack and secrecy of the user's credentials. 2015 ACM. -
Comparing keyframe extraction for video summarization in CPU and GPU
Most of the information is captured through multimedia techniques. Videos contain many frames which might be redundant. Since processing of many frames is involved, these redundant frames must be removed for better and efficient results. Summarizing these frames by removing similar frames can speed up processing. In this paper video summarization is achieved by generating key frames. Key frames are generated using discrete wavelet transforms (DWT) technique and we subtract background from the keyframes to get region of interest. A video of 920&Times;720 resolution and length 120 second was used as test video and the run-time was 111 second in CPU and 60 second in GPU. The speed up is nearly 100%. A HD video which took 23 minutes in serial implementation to extract foreground object from key frames generated was reduced to 7 minutes using GPU acceleration. 2015 IEEE. -
STREE: A Secured Tree based Routing with Energy Efficiency in Wireless Sensor Network
The Wireless Sensor Network (WSN) applications are today not only limited to the research stage rather it has been adopted practically in many defense as well as general civilians applications. It has been witness that extensive research have been conducted towards energy efficient routing and communication protocols and it has been reached to an acceptable stages, but without having a secure communications wide acceptance of the application is not likely. Due to unique characteristics of WSN, the security schemes suggested for other wireless networks are not applicable to WSN. This paper introduces an novel tree based technique called as Secure Tree based Routing with Energy Efficiency or STREE using clustering approximation along with lightweight key broadcasting mechanism in hierarchical routing protocol. The outcome of the study was compared with standard SecLEACH to find that proposed system ensure better energy efficiency and security. 2015 IEEE. -
A comprehensive survey on features and methods for speech emotion detection
Human computer interaction will be natural and effective when the interfaces are sensitive to human emotion or stress. Previous studies were mainly focused on facial emotion recognition but speech emotion detection is gaining importance due its wide range of applications. Speech emotion recognition still remains a challenging task in the field of affective computing as no defined standards exist for emotion classification. Speech signal carries large information related to the emotions conveyed by a person. Speech recognition system fails miserably if robust techniques are not implemented to address the variations in speech due to emotion. Emotion detection from speech has two main steps. They are feature extraction and classification. The goal of this paper is to give an overview on the types of corpus, features and classification techniques that are associated with speech emotion recognition. 2015 IEEE. -
A secure image-based authentication scheme employing DNA crypto and steganography
Authentication is considered as one of the critical aspects of Information security to ensure identity. Authentication is generally carried out using conventional authentication methods such as text based passwords, but considering the increased usage of electronic services a user has to remember many id-password pairs which often leads to memorability issues. This inspire users to reuse passwords across e-services, but this practice is vulnerable to security attacks. To improve security strength, various authentication techniques have been proposed including two factor schemes based on smart card, tokens etc. and advanced biometric techniques. Graphical Image based authentication systems has received relevant diligence as it provides better usability by way of memorable image passwords. But the tradeoff between usability and security is a major concern while strengthening authentication. This paper proposes a novel twoway secure authentication scheme using DNA cryptography and steganography considering both security and usability. The protocol uses text and image password of which text password is converted into cipher text using DNA cryptography and embedded into image password by applying steganography. Hash value of the generated stego image is calculated using SHA-256 and the same will be used for verification to authenticate legitimate user. 2015 ACM. -
Ceria doped titania nano particles: Synthesis and photocatalytic activity
Ceria (0.5, 1 and 2 mol%) doped titania nano catalysts were prepared by combustion synthesis method, using titanium isopropoxide as the starting material. The prepared catalysts were characterized by X-ray diffraction (XRD), Energy dispersive X-ray analysis (EDX), Scanning electron microscopy (SEM) and Infra red spectroscopy (FTIR). Total acidity of the prepared catalysts were determined by temperature programmed desorption of ammonia (TPD - NH3). XRD pattern of 1% ceria doped titania obtained by calcinations at 873 K indicated that the samples were crystalline with a mixture of anatase and rutile phase. No peaks corresponding to cerium oxide were observed XRD patterns indicating that the amount of cerium is negligible on the surface of titania catalyst. The photo catalytic activity was evaluated for the degradation of methylene blue (MB) under visible light irradiation. The degradation rates of MB on cerium doped TiO2 samples were higher than that of pure TiO2. The introduction of structural defects (cationic ceria dopant) into the titania crystal lattice leads to the change of band gap energy. As a result, the excitation energy is expanded from UV light of anatase TiO2 to visible light for ceria doped titania. 2016 Elsevier Ltd. -
Performance analysis of training algorithms of multilayer perceptrons in diabetes prediction
Artificial Intelligence plays a vital role in developing machines or software that can create intelligence. Artificial Neural Networks is a field of neuroscience which contributes tremendous developments in Artificial Intelligence. This paper focuses on the study of performance of various training algorithms of Multilayer Perceptrons in Diabetes Prediction. In this study, we have used Pima Indian Diabetes data set from UCI Machine Learning Repository as input dataset. The system is implemented in MatlabR2013. The Pima Indian Diabetes dataset consists of about 768 instances. The input data is the patient history and the target output is the prediction result as tested positive or tested negative. From the performance analysis, it was observed that out of all the training algorithms, Levenberg-Marquardt Algorithm has given optimal training results. 2015 IEEE. -
Partial load shedding using ant colony algorithm in smart grid environment
Effective power distribution methodology is one of the basic necessities to meet the increasing power demand in any power system. Load shedding is done when power demand is more than power generation, to sustain the power system stability. Load shedding methods followed today shed a particular load completely, neglecting the critical consumers within the system. Controlling the loads at individual utility level in smart grid system enables us to put a maximum power limit on utility. Hence by partially shedding the load, demand can be reduced. The technique used here utilizes ant colony algorithm to choose a maximum power limit for each load dynamically based on the importance and priority of load. This method forces the consumer to manage his load internally based on criticality. It also effectively makes use of availability based tariff schemes. 2015 IEEE. -
Friction stir welding of aluminum alloy 1100 and titanium-al alloy
A intercalating joint between Al and Ti alloy is friction stir welded using a high speed steel tool. The material mixing occurs mainly in the shoulder region while the pin region shows nominal mixing. Microscopy and hardness experiments indicate sporadic formation of intermetallic compounds. The joint region near the shoulder and to some extent below it shows increase in hardness compared to the base Ti alloy. Copyright 2016 by ASME. -
An approach to improvise recognition rate from occluded and pose variant faces
Face recognition is increasingly gaining popularity in today's field mainly because one of the major applications of face recognition, surveillance cameras are being used in real world applications. At the same time, researchers are trying to increase the accuracy of recognition as recognizing face from an unconstrained faces is naturally difficult. In the case of real world application, during image capture there are high chances of faces appearing with different poses, face subjected to illumination and occlusion. In this paper we propose a model that can increase the recognition rate with faces of different pose and faces subjected to occlusion. We introduce the technique of in-painting to restore the occluded face in a frame of video. A dictionary set is created with restored occluded face and faces with varying inclination. In our proposed model, Discrete Curvelet Transform is used to extract features. Comparison with traditional method shows a better recognition rate. 2015 IEEE. -
Encryption of motion vector based compressed video data
Enormous size of video data for natural scene and objects is a burden, threat for practical applications and thus there is a strong requirement of compression and encryption of video data. The proposed encryption technique considers motion vector components of the compressed video data and conceals them for their protection. Since the motion vectors exhibit redundancies, further reduction of these redundancies are removed through run-length coding prior to the application of encryption operation. For this, the motion vectors are represented in terms of ordered pair (val, run) corresponding to the motion components along the row and column dimensions, where val represents value of the motion vector while run represents the length of repetition of val. However, an adjustment for having maximal run is made by merging the smaller run value. Eventually we encrypted the val components using knapsack algorithm before sending them to the receiver. The method has been formulated, implemented and executed on real video data. The proposed method has also been evaluated on the basis of some performance measures namely PSNR, MSE, SSIM and the results are found to be satisfactory. Springer International Publishing Switzerland 2016. -
Micromachining process-current situation and challenges
The rapid progress in the scientific innovations and the hunt for the renewable energy increases the urge for producing the bio electronic products, solar cells, bio batteries, nano robots, MEMS, blood less surgical tools which can be possible with the aid of the micromachining. This article helps us to understand the evolution and the challenges faced by the micromachining process. Micro machining is an enabling technology that facilitates component miniaturization and improved performance characteristics. Growing demand for less weight, high accuracy, high precision, meagre lead time, reduced batch size, less human interference are the key drivers for the micromachining than the conventional machining process. Owned by the authors, published by EDP Sciences, 2015. -
An analysis of load balancing algorithms in the cloud environment
The emerging area in an IT environment is Cloud Computing. There are many advantages of the computing but unfortunately, allocation of the job request effectively is a trouble. It requires lots of infra structural commitments and the quality inputs of the resources. Also, in the cloud computing environment, Load Balancing is an important aspect. Efficient load balancing algorithm helps the resource to have optimized utilization with the proper dissemination of the resources to the cloud user in pay-as-you-say-manner. It also supports ranking the job request based on the priority with the help of scheduling technique. We present the various types of Load Balancing Techniques in the different platform of Cloud Environment specified in SLA (Service level Agreement). 2016 IEEE. -
Segmentation of ancient and historical gilgit manuscripts
The Gilgit manuscripts belong to fifth century A.D. and are oeuvre of texts which deal with Buddhist work. It is one of the oldest manuscripts in the world and is considered to be a milestone in the history of Buddhist works in India. It is a collection of both official and unofficial Buddhist works which are believed to have helped in the evolution of many literatures including Chinese, Japanese, and Sanskrit. Since this manuscript is almost seventeen centuries old it has not been able to fully decipher the text yet. It has been laminated by the National Archives of India which proves it is one of the most important literatures concerning India. In this paper, we perform character- based image segmentation on Gilgit manuscript in order to simplify and to better identify character in the image of the manuscript. The employed method gives an accuracy of nearly 87%. Springer India 2016. -
Rectangular microstrip antenna for WLAN application
This paper deals with the design of rectangular microstrip patch antenna for Wireless applications. In this paper a modified slotted microstrip antenna design for 2.5GHz operation is proposed. This provides improved performance in terms of lower return loss and higher gain. This is possible by inclusion of slots appropriately on the patch shape. The substrate material used in this design is Duroid5880 with permittivity 2.2 and size 47.43mm 39.65mm 1.6mm. ANSOFT HFSS EM simulator has been used for design and simulation of the microstrip antenna. The various antenna parameters such as frequency, VSWR, gain and directivity are analyzed to characterize the proposed antenna. 2015 IEEE. -
A modified approach for extraction and association of triplets
In this paper we present an enhanced algorithm with modified approach to extricate various Triplets i.e. subject-predicate-object from Natural language sentences. The Treebank Structure and the Typed Dependencies obtained from Stanford Parser are used to elicit multiple triplets from English Sentences. Typed Dependencies represents grammatical connections among the words of any sentence and represents how triplets are associated. The intended interpretation behind the extraction of Triplets is that the subject is acting on the object in a way described by the predicate. In graphical form it can be considered that subject and object will be acting as nodes i.e. entities and predicate as edges i.e. relationship. The resulting triplets and relations can be useful for building and analysis of a social network graph and for generating communication pattern and Information retrieval. 2015 IEEE. -
A proof of concept implementation of a mobile based authentication scheme without password table for cloud environment
Cloud computing is a fast growing technology offering a wide range of software and infrastructure services on a pay-per-use basis. Many small and medium businesses (SMB's) have adopted this utility based Computing Model as it contributes to reduced operational and capital expenditure. Though the resource sharing feature adopted by Cloud service providers (CSP's) enables the organizations to invest less on infrastructure, it also raises concerns about the security of data stored at CSP's premises. The fact that data is prone to get accessed by the insiders or by other customers sharing the storage space is a matter of concern. Regulating access to protected resources requires reliable and secure authentication mechanism, which assures that only authorized users are provided access to the services and resources offered by CSP. This paper proposes a strong two-factor authentication mechanism using password and mobile token. The proposed model provides Single Sign-on (SSO) functionality and does not require a password table. Besides introducing the authentication scheme, the proof of concept implementation is also provided. 2015 IEEE.