Pub Date : 2010-12-01DOI: 10.1109/INDCON.2010.5712659
K. Ramakrishnan, G. Ray
In this paper, we consider the problem of delay-dependent robust stability of a class of linear neutral systems with mixed time-delays and nonlinear perturbations using Lyapunov-Krasovskii functional approach. By constructing a candidate Lyapunov-Krasovskii (LK) functional, a less conservative robust delay-dependent stability criterion is proposed in terms of matrix inequalities. Reduction in conservatism of the proposed stability criterion over recently reported results is attributed to the candidate LK functional, and to tighter bounding of the time-derivative of the functional without neglecting any useful terms in the delay-dependent stability analysis. The analysis, eventually, culminates into a stability condition in convex LMI framework, and is solved non-conservatively at boundary conditions. The effectiveness of the proposed stability criterion is demonstrated through standard numerical examples.
{"title":"An improved delay-dependent stability criterion for neutral systems with mixed time-delays and nonlinear perturbations","authors":"K. Ramakrishnan, G. Ray","doi":"10.1109/INDCON.2010.5712659","DOIUrl":"https://doi.org/10.1109/INDCON.2010.5712659","url":null,"abstract":"In this paper, we consider the problem of delay-dependent robust stability of a class of linear neutral systems with mixed time-delays and nonlinear perturbations using Lyapunov-Krasovskii functional approach. By constructing a candidate Lyapunov-Krasovskii (LK) functional, a less conservative robust delay-dependent stability criterion is proposed in terms of matrix inequalities. Reduction in conservatism of the proposed stability criterion over recently reported results is attributed to the candidate LK functional, and to tighter bounding of the time-derivative of the functional without neglecting any useful terms in the delay-dependent stability analysis. The analysis, eventually, culminates into a stability condition in convex LMI framework, and is solved non-conservatively at boundary conditions. The effectiveness of the proposed stability criterion is demonstrated through standard numerical examples.","PeriodicalId":109071,"journal":{"name":"2010 Annual IEEE India Conference (INDICON)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123984588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/INDCON.2010.5712608
A. Chandra, A. Patra, C. Bose
This paper provides a framework for error rate performance analysis of M-ary phase-shift keying (MPSK) systems with improper phase estimation over some common fading channels obeying Rayleigh, Rician, or Nakagami-m distribution. In addition, the channel is also perturbed by additive white Gaussian noise (AWGN). The phase distortions considered in the paper are random, unbiased, i.e. having zero-mean, and follows Tikhonov distribution. Analytical average symbol error probability (SEP) is calculated through a new efficient method and plotted as a function of signal to noise ratio (SNR) for different values of the modulation order, M. Our approach relies upon knowledge of the moment generating function (MGF) of the received SNR. The resulting expression is an integral over a finite range of integrands containing only elementary functions. Extensive Monte Carlo simulations were performed to validate the theoretical results. Although the SEP can be computed via direct numerical integration, the MGF method performs far better because direct integration suffers from numerical instability and inaccuracy due to the presence of infinite integration limits or may contain complex mathematical functions.
{"title":"Effect of imperfect phase synchronization on the error rate performance of MPSK in Rayleigh, Rician and Nakagami fading channels","authors":"A. Chandra, A. Patra, C. Bose","doi":"10.1109/INDCON.2010.5712608","DOIUrl":"https://doi.org/10.1109/INDCON.2010.5712608","url":null,"abstract":"This paper provides a framework for error rate performance analysis of M-ary phase-shift keying (MPSK) systems with improper phase estimation over some common fading channels obeying Rayleigh, Rician, or Nakagami-m distribution. In addition, the channel is also perturbed by additive white Gaussian noise (AWGN). The phase distortions considered in the paper are random, unbiased, i.e. having zero-mean, and follows Tikhonov distribution. Analytical average symbol error probability (SEP) is calculated through a new efficient method and plotted as a function of signal to noise ratio (SNR) for different values of the modulation order, M. Our approach relies upon knowledge of the moment generating function (MGF) of the received SNR. The resulting expression is an integral over a finite range of integrands containing only elementary functions. Extensive Monte Carlo simulations were performed to validate the theoretical results. Although the SEP can be computed via direct numerical integration, the MGF method performs far better because direct integration suffers from numerical instability and inaccuracy due to the presence of infinite integration limits or may contain complex mathematical functions.","PeriodicalId":109071,"journal":{"name":"2010 Annual IEEE India Conference (INDICON)","volume":"365 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115978219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/INDCON.2010.5712589
A. Sutradhar, A. Sengupta, V. Challa
In the present work, artificial neural network (ANN) has been used to identify a servo-driven inverted pendulum system. The inverted pendulum is a benchmark problem of nonlinear multivariable system with inherent instability. The multi variable system has been considered with servomotor supply voltage as the input and four states of the system being the outputs. An LSVF controller has been used to stabilize the system for identification in closed loop. Here the non linear model of the inverted pendulum has been simulated. The Levenberg-Marquardt back-propagation method has been used for the non linear system identification via Feed-forward Neural Network (FNN). The neural network is trained using the error between the model's outputs and the plant's actual outputs. The results show good match between predicted and actual outputs.
{"title":"Identification of servo-driven inverted pendulum system using neural network","authors":"A. Sutradhar, A. Sengupta, V. Challa","doi":"10.1109/INDCON.2010.5712589","DOIUrl":"https://doi.org/10.1109/INDCON.2010.5712589","url":null,"abstract":"In the present work, artificial neural network (ANN) has been used to identify a servo-driven inverted pendulum system. The inverted pendulum is a benchmark problem of nonlinear multivariable system with inherent instability. The multi variable system has been considered with servomotor supply voltage as the input and four states of the system being the outputs. An LSVF controller has been used to stabilize the system for identification in closed loop. Here the non linear model of the inverted pendulum has been simulated. The Levenberg-Marquardt back-propagation method has been used for the non linear system identification via Feed-forward Neural Network (FNN). The neural network is trained using the error between the model's outputs and the plant's actual outputs. The results show good match between predicted and actual outputs.","PeriodicalId":109071,"journal":{"name":"2010 Annual IEEE India Conference (INDICON)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116230515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/INDCON.2010.5712729
S. Saha, R. Suryavanshi
Offshore oil rigs use large dc drives, usually fed from a.c. utility services through ac/dc converters, thus distorting current and voltage waveforms. Passive filters have been very effective solution for the harmonic mitigation as well as reactive VAR compensation. However, improper choice of filter components may lead to severe voltage and current stress to power system components or even sometimes may further deteriorate the power quality. This paper describes an effective design procedure of passive filter to mitigate power system harmonics of a typical offshore oil rig.
{"title":"Power system harmonic mitigation of an offshore oil rig using passive shunt filter","authors":"S. Saha, R. Suryavanshi","doi":"10.1109/INDCON.2010.5712729","DOIUrl":"https://doi.org/10.1109/INDCON.2010.5712729","url":null,"abstract":"Offshore oil rigs use large dc drives, usually fed from a.c. utility services through ac/dc converters, thus distorting current and voltage waveforms. Passive filters have been very effective solution for the harmonic mitigation as well as reactive VAR compensation. However, improper choice of filter components may lead to severe voltage and current stress to power system components or even sometimes may further deteriorate the power quality. This paper describes an effective design procedure of passive filter to mitigate power system harmonics of a typical offshore oil rig.","PeriodicalId":109071,"journal":{"name":"2010 Annual IEEE India Conference (INDICON)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121115143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/INDCON.2010.5712691
N. Saxena, Ashwani Kumar
This paper considers the importance of the load voltage dynamics in autonomous hybrid power system. In steady state the reactive powers of the system components are balanced but small perturbations at supply or load end change the dynamics of the system. The system attains its steady state in some time with the flow of additional reactive power in the system through either synchronous generator or induction generator or FACTS controller STATCOM. In this paper, the interaction between the load and the power system is explored in terms of load and system transfer function. A comparison is given with and without the interaction of load with system. It is found that the system reactive power demand by the STATCOM and voltage variation will be reduced if the load interaction with system is also considered.
{"title":"Load modeling interaction on hybrid power system using STATCOM","authors":"N. Saxena, Ashwani Kumar","doi":"10.1109/INDCON.2010.5712691","DOIUrl":"https://doi.org/10.1109/INDCON.2010.5712691","url":null,"abstract":"This paper considers the importance of the load voltage dynamics in autonomous hybrid power system. In steady state the reactive powers of the system components are balanced but small perturbations at supply or load end change the dynamics of the system. The system attains its steady state in some time with the flow of additional reactive power in the system through either synchronous generator or induction generator or FACTS controller STATCOM. In this paper, the interaction between the load and the power system is explored in terms of load and system transfer function. A comparison is given with and without the interaction of load with system. It is found that the system reactive power demand by the STATCOM and voltage variation will be reduced if the load interaction with system is also considered.","PeriodicalId":109071,"journal":{"name":"2010 Annual IEEE India Conference (INDICON)","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126024960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/INDCON.2010.5712754
V. Srivastava, K. S. Yadav, G. Singh
In this paper, we have explored the design features of a Double-Pole Four-Throw (DP4T) RF CMOS switch with use of a novel Vertical Slit Field Effect Transistor (VSFET). This proposed switch circuit uses the double-gate which minimizes the number of transistors and increases the logic density of the transistor per unit area as compare to simple switch. These double gates are independently controlled. This will provide a switch with a drive circuit that free from signal propagation delay and additional voltage power supply. Further, main objective is to provide a plurality of such switches arranged in a densely configured switch array, where the power and circuit area is reduced as compared to a tied gate configuration.
{"title":"Double-Pole Four-Throw RF CMOS switch design with double-gate transistors","authors":"V. Srivastava, K. S. Yadav, G. Singh","doi":"10.1109/INDCON.2010.5712754","DOIUrl":"https://doi.org/10.1109/INDCON.2010.5712754","url":null,"abstract":"In this paper, we have explored the design features of a Double-Pole Four-Throw (DP4T) RF CMOS switch with use of a novel Vertical Slit Field Effect Transistor (VSFET). This proposed switch circuit uses the double-gate which minimizes the number of transistors and increases the logic density of the transistor per unit area as compare to simple switch. These double gates are independently controlled. This will provide a switch with a drive circuit that free from signal propagation delay and additional voltage power supply. Further, main objective is to provide a plurality of such switches arranged in a densely configured switch array, where the power and circuit area is reduced as compared to a tied gate configuration.","PeriodicalId":109071,"journal":{"name":"2010 Annual IEEE India Conference (INDICON)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114546729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/INDCON.2010.5712636
P. Babu, M. Vanamali, M. Kumar, V. Hemachandra
This paper proposes a novel heuristic method known as Loop-Eliminating (L-E) method for Distribution System Network Reconfiguration. Network reconfiguration is the process of altering the topological structure of the electrical distribution system by changing the status of sectionalizing switches/tie switches. Network Reconfiguration can be used as a multi objective tool to solve various problems such as loss minimization, service restoration and load balancing in distribution systems. This paper presents an efficient algorithm based upon L-E method to solve the loss minimization problem for a given distribution system. The L-E method is a computationally attractive heuristic method, used to find out optimal configuration of a given radial distribution system. The proposed algorithm is coded in MATLAB 2009b version on a PC with 1GB RAM and Intel Core 2 Duo 1.8 GHz processor. To check the validity of the algorithm, the proposed algorithm has been tested on standard IEEE 33 and 69 bus distribution systems and the simulated results are used to confirm the capability of the proposed algorithm being applied to the systems.
{"title":"Network reconfiguration in distribution systems using L-E method","authors":"P. Babu, M. Vanamali, M. Kumar, V. Hemachandra","doi":"10.1109/INDCON.2010.5712636","DOIUrl":"https://doi.org/10.1109/INDCON.2010.5712636","url":null,"abstract":"This paper proposes a novel heuristic method known as Loop-Eliminating (L-E) method for Distribution System Network Reconfiguration. Network reconfiguration is the process of altering the topological structure of the electrical distribution system by changing the status of sectionalizing switches/tie switches. Network Reconfiguration can be used as a multi objective tool to solve various problems such as loss minimization, service restoration and load balancing in distribution systems. This paper presents an efficient algorithm based upon L-E method to solve the loss minimization problem for a given distribution system. The L-E method is a computationally attractive heuristic method, used to find out optimal configuration of a given radial distribution system. The proposed algorithm is coded in MATLAB 2009b version on a PC with 1GB RAM and Intel Core 2 Duo 1.8 GHz processor. To check the validity of the algorithm, the proposed algorithm has been tested on standard IEEE 33 and 69 bus distribution systems and the simulated results are used to confirm the capability of the proposed algorithm being applied to the systems.","PeriodicalId":109071,"journal":{"name":"2010 Annual IEEE India Conference (INDICON)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114797528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/INDCON.2010.5712694
P. Bera, D. Das, T. Basu
In this paper, the coordinated operation of conventional power system stabilizer (CPSS) and thyristor controlled series capacitor (TCSC) is studied. The analysis of mode controllability is used to select the effective location for TCSC. The performance of TCSC equipped with a phase lead-lag controller is investigated. The controllers design problem is formulated as an optimization problem. The genetic algorithm (GA) is used to search for optimal settings of controller parameters. A coordinated control scheme is applied to a three machine nine bus power system. The proposed control scheme is tested under different loading conditions and analysis reveals that the coordinated control of CPSS and TCSC equipped with lead-lag controller gives better dynamic performances as compared to with only CPSSs.
{"title":"Coordinated design of excitation and TCSC-based stabilizers for multimachine power system","authors":"P. Bera, D. Das, T. Basu","doi":"10.1109/INDCON.2010.5712694","DOIUrl":"https://doi.org/10.1109/INDCON.2010.5712694","url":null,"abstract":"In this paper, the coordinated operation of conventional power system stabilizer (CPSS) and thyristor controlled series capacitor (TCSC) is studied. The analysis of mode controllability is used to select the effective location for TCSC. The performance of TCSC equipped with a phase lead-lag controller is investigated. The controllers design problem is formulated as an optimization problem. The genetic algorithm (GA) is used to search for optimal settings of controller parameters. A coordinated control scheme is applied to a three machine nine bus power system. The proposed control scheme is tested under different loading conditions and analysis reveals that the coordinated control of CPSS and TCSC equipped with lead-lag controller gives better dynamic performances as compared to with only CPSSs.","PeriodicalId":109071,"journal":{"name":"2010 Annual IEEE India Conference (INDICON)","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114315230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/INDCON.2010.5712604
A. Vuppala, K. S. Sekhara Rao, S. Chakrabarti
The increasing use of wireless systems is creating great deal of interest in the development of robust speech systems in wireless environment. The major degradations involved in wireless environment are: effect of varying background conditions, degradation due to speech coders and errors due to wireless channels. In this paper, we presented the effect of speech coding on text independent speaker identification (SI). Speech coders considered in this work are GSM full rate (ETSI 06.10), CELP (FS-1016), and MELP (TI 2.4kbps). The amount of distortion introduced by coding is measured using log-likelihood ratio (LLR), weighted spectral slope (WSS) and log-spectral distance (LSD). The effect of coding on SI is analyzed by building SI system using both vocal track system and excitation source features. We observed that there is a significant reduction of performance in SI system due to coding, and effect is more prominent in case of SI system build with source features. We also observed that, speaker characteristics are well preserved in case of MELP compared to CELP even though MELP coder bit rate is less than CELP.
{"title":"Effect of speech coding on speaker identification","authors":"A. Vuppala, K. S. Sekhara Rao, S. Chakrabarti","doi":"10.1109/INDCON.2010.5712604","DOIUrl":"https://doi.org/10.1109/INDCON.2010.5712604","url":null,"abstract":"The increasing use of wireless systems is creating great deal of interest in the development of robust speech systems in wireless environment. The major degradations involved in wireless environment are: effect of varying background conditions, degradation due to speech coders and errors due to wireless channels. In this paper, we presented the effect of speech coding on text independent speaker identification (SI). Speech coders considered in this work are GSM full rate (ETSI 06.10), CELP (FS-1016), and MELP (TI 2.4kbps). The amount of distortion introduced by coding is measured using log-likelihood ratio (LLR), weighted spectral slope (WSS) and log-spectral distance (LSD). The effect of coding on SI is analyzed by building SI system using both vocal track system and excitation source features. We observed that there is a significant reduction of performance in SI system due to coding, and effect is more prominent in case of SI system build with source features. We also observed that, speaker characteristics are well preserved in case of MELP compared to CELP even though MELP coder bit rate is less than CELP.","PeriodicalId":109071,"journal":{"name":"2010 Annual IEEE India Conference (INDICON)","volume":"204 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128877375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/INDCON.2010.5712679
Md. Anwar Hussain
Biometric object based person identification is now gaining reliability and high acceptability. Iris as biometric object is used for such identification in many important applications. Almost all techniques, that use iris for recognition is not fully accurate. In this paper we present an accurate iris recognition system that is based on feature extraction in the eigen space and treating the iris in the lower dimensionality. Eigen irises are constructed from a set of iris images of a person, and a given iris image is recognized by passing it through different sets of eigen irises obtained from the sets of iris images of different persons in the database. We considered different numbers of eigenirises for each person, and compressed and compressed noisy iris images as well as only noisy iris images for recognition. Results show accurate person identification using this technique.
{"title":"Eigenspace based accurate iris recognition system","authors":"Md. Anwar Hussain","doi":"10.1109/INDCON.2010.5712679","DOIUrl":"https://doi.org/10.1109/INDCON.2010.5712679","url":null,"abstract":"Biometric object based person identification is now gaining reliability and high acceptability. Iris as biometric object is used for such identification in many important applications. Almost all techniques, that use iris for recognition is not fully accurate. In this paper we present an accurate iris recognition system that is based on feature extraction in the eigen space and treating the iris in the lower dimensionality. Eigen irises are constructed from a set of iris images of a person, and a given iris image is recognized by passing it through different sets of eigen irises obtained from the sets of iris images of different persons in the database. We considered different numbers of eigenirises for each person, and compressed and compressed noisy iris images as well as only noisy iris images for recognition. Results show accurate person identification using this technique.","PeriodicalId":109071,"journal":{"name":"2010 Annual IEEE India Conference (INDICON)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130562114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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