Pub Date : 2012-07-26DOI: 10.1109/ICOE.2012.6409572
D. Dinakar, P. V. Rao, P. Kishore, K. Srimannarayana, M. S. Shankar, S. Rao
An inexpensive intensity modulated force sensor that used plastic optical fiber and a cantilever beam is demonstrated. The plastic optical fiber is bonded on the surface of metal beam made of spring-steel and subjected to force at the end of the cantilever. The performance of the sensor is evaluated during macro-bending of the beam for applied forces. The sensor is tested for both the upward and downward forces and negligible hysteresis is observed in the experimental results. The proposed sensor can replace stain gauges in structural bending applications.
{"title":"A simple plastic optical fiber force sensor","authors":"D. Dinakar, P. V. Rao, P. Kishore, K. Srimannarayana, M. S. Shankar, S. Rao","doi":"10.1109/ICOE.2012.6409572","DOIUrl":"https://doi.org/10.1109/ICOE.2012.6409572","url":null,"abstract":"An inexpensive intensity modulated force sensor that used plastic optical fiber and a cantilever beam is demonstrated. The plastic optical fiber is bonded on the surface of metal beam made of spring-steel and subjected to force at the end of the cantilever. The performance of the sensor is evaluated during macro-bending of the beam for applied forces. The sensor is tested for both the upward and downward forces and negligible hysteresis is observed in the experimental results. The proposed sensor can replace stain gauges in structural bending applications.","PeriodicalId":142915,"journal":{"name":"2012 International Conference on Optical Engineering (ICOE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130049470","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 : 2012-07-26DOI: 10.1109/ICOE.2012.6409597
S. Kumar, S. Raghuwanshi
There are many numerical approaches have been developed to analyze general dielectric waveguides. Compared with other numerical techniques, the beam propagation method (BPM) is the most popular and powerful numerical technique for modeling of guided wave photonic devices and most commercial software for such modeling are based on it. To date numerous algorithms for BPM have been proposed and successfully applied to a very wide class of dielectric optical waveguide structures. In this paper, we have analyzed the Multimode interference (MMI) coupler by Beam Propagation Method (BPM) having a step discontinuity between thin planar slab waveguide with wide thick planar slab waveguide. The effect of the waveguide width on the performance of MMI coupler has been analyzed. It has been found that power transmission is asymmetric with waveguide width variation. The relation between the amount of allowed modes with power transmission has been predicted along with pulse propagation through MMI coupler.
{"title":"Analysis of step discontinuities in rectangular MMI coupler by beam propagation method","authors":"S. Kumar, S. Raghuwanshi","doi":"10.1109/ICOE.2012.6409597","DOIUrl":"https://doi.org/10.1109/ICOE.2012.6409597","url":null,"abstract":"There are many numerical approaches have been developed to analyze general dielectric waveguides. Compared with other numerical techniques, the beam propagation method (BPM) is the most popular and powerful numerical technique for modeling of guided wave photonic devices and most commercial software for such modeling are based on it. To date numerous algorithms for BPM have been proposed and successfully applied to a very wide class of dielectric optical waveguide structures. In this paper, we have analyzed the Multimode interference (MMI) coupler by Beam Propagation Method (BPM) having a step discontinuity between thin planar slab waveguide with wide thick planar slab waveguide. The effect of the waveguide width on the performance of MMI coupler has been analyzed. It has been found that power transmission is asymmetric with waveguide width variation. The relation between the amount of allowed modes with power transmission has been predicted along with pulse propagation through MMI coupler.","PeriodicalId":142915,"journal":{"name":"2012 International Conference on Optical Engineering (ICOE)","volume":"20 S28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127035808","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 : 2012-07-26DOI: 10.1109/ICOE.2012.6409588
S. Kulkarni, R. Sharma, Preeta Sharan, R. R. Gowd
Bandwidth and Delay are quality parameters that can be guaranteed for new connections that are offered to the network by finding a suitable path in the network. Finding such a suitable path is the task of QoS routing techniques developed for IP Optical networks based on Multiprotocol Label Switching (MPLS). In this paper we focus on dynamic routing of Bandwidth (1Mbps/link) and delay (1ms/link) guaranteed flows in optical networks based on label forwarding techniques. We are presenting simulation results to compare the performances of Optical Networks with Wired networks under wide range of topologies and system parameters. The simulation results show that considering an optical fibre as link, the call blocking ratio is reduced by 2.4% as compared to a non optical link in same topological environment.
{"title":"New dynamic QoS routing algorithm for optical networks based on MPLS with delay and Bandwidth as constraints","authors":"S. Kulkarni, R. Sharma, Preeta Sharan, R. R. Gowd","doi":"10.1109/ICOE.2012.6409588","DOIUrl":"https://doi.org/10.1109/ICOE.2012.6409588","url":null,"abstract":"Bandwidth and Delay are quality parameters that can be guaranteed for new connections that are offered to the network by finding a suitable path in the network. Finding such a suitable path is the task of QoS routing techniques developed for IP Optical networks based on Multiprotocol Label Switching (MPLS). In this paper we focus on dynamic routing of Bandwidth (1Mbps/link) and delay (1ms/link) guaranteed flows in optical networks based on label forwarding techniques. We are presenting simulation results to compare the performances of Optical Networks with Wired networks under wide range of topologies and system parameters. The simulation results show that considering an optical fibre as link, the call blocking ratio is reduced by 2.4% as compared to a non optical link in same topological environment.","PeriodicalId":142915,"journal":{"name":"2012 International Conference on Optical Engineering (ICOE)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127993721","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 : 2012-07-26DOI: 10.1109/ICOE.2012.6409595
P. Sharan, G. Thakur, S. Sanjay, Chitranjan
This paper presents modelling of Fiber Bragg Grating (FBG), in order to provide the optimized parameters for designing sensor. FBG sensor applications require narrow spectral response for achieving good performance. Spectral characteristics parameters like FBG length, grating pitch, cladding index, apodization and (Full Width Half Maximum) FWHM are varied for achieving good response. Simulation results from R-Soft show that at L=2500μm, 99.89% reflectivity has been obtained. Suppression of side lobes in the spectrum with cosine apodization results in efficiency of 97.97% and sharp spectral response having FWHM =1.01μm has been achieved and hence makes FBG suitable for sensor application.
{"title":"Modelling of Fiber Bragg Grating for sensor application","authors":"P. Sharan, G. Thakur, S. Sanjay, Chitranjan","doi":"10.1109/ICOE.2012.6409595","DOIUrl":"https://doi.org/10.1109/ICOE.2012.6409595","url":null,"abstract":"This paper presents modelling of Fiber Bragg Grating (FBG), in order to provide the optimized parameters for designing sensor. FBG sensor applications require narrow spectral response for achieving good performance. Spectral characteristics parameters like FBG length, grating pitch, cladding index, apodization and (Full Width Half Maximum) FWHM are varied for achieving good response. Simulation results from R-Soft show that at L=2500μm, 99.89% reflectivity has been obtained. Suppression of side lobes in the spectrum with cosine apodization results in efficiency of 97.97% and sharp spectral response having FWHM =1.01μm has been achieved and hence makes FBG suitable for sensor application.","PeriodicalId":142915,"journal":{"name":"2012 International Conference on Optical Engineering (ICOE)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128767902","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 : 2012-07-26DOI: 10.1109/ICOE.2012.6409569
J. V. Thombare, V. Fulari, M. Rath, S. Han
We report electrochemically synthesized polypyrrole (Ppy) thin films. The polypyrrole thin films were deposited by galvanostatic as well as potentiostatic deposition mode. The polypyrrole thin film was characterized by Scanning Electron Microscopy (SEM) and UV-VIS spectroscopy. The optical absorption study gives the absorption peaks nearly at the wavelength of 430 nm to 438 nm and an absorption shoulder beyond the wavelength of 800 nm. The optical absorption measurements were carried out for the Ppy thin films which are prepared with different deposition times for a fixed concentration of electrolyte and monomer solution.
{"title":"Optical absorption study of electrochemically synthesized polypyrrole(Ppy) thin films","authors":"J. V. Thombare, V. Fulari, M. Rath, S. Han","doi":"10.1109/ICOE.2012.6409569","DOIUrl":"https://doi.org/10.1109/ICOE.2012.6409569","url":null,"abstract":"We report electrochemically synthesized polypyrrole (Ppy) thin films. The polypyrrole thin films were deposited by galvanostatic as well as potentiostatic deposition mode. The polypyrrole thin film was characterized by Scanning Electron Microscopy (SEM) and UV-VIS spectroscopy. The optical absorption study gives the absorption peaks nearly at the wavelength of 430 nm to 438 nm and an absorption shoulder beyond the wavelength of 800 nm. The optical absorption measurements were carried out for the Ppy thin films which are prepared with different deposition times for a fixed concentration of electrolyte and monomer solution.","PeriodicalId":142915,"journal":{"name":"2012 International Conference on Optical Engineering (ICOE)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133347127","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 : 2012-07-26DOI: 10.1109/ICOE.2012.6409590
K. Ramanujam, S. Talbatulla
In this paper, we evaluate the performance of a burst retransmission method for an optical burst switched network with intermediate-node-initiation (INI) signaling technique. The proposed method tries to reduce the burst contention probability at the intermediate core nodes. We develop an analytical model to get the burst contention probability and burst loss probability for an optical burst switched network with intermediate-node-initiation signaling technique. The proposed method uses the optical burst retransmission method. We simulate the performance of the optical burst retransmission. Simulation results show that at low traffic loads the loss probability is low compared to the conventional burst retransmission in the OBS network. Result also show that the retransmission method for OBS network with intermediate-node-initiation signaling technique significantly reduces the burst loss probability.
{"title":"Performance evaluation of OBS networks with INI signaling technique","authors":"K. Ramanujam, S. Talbatulla","doi":"10.1109/ICOE.2012.6409590","DOIUrl":"https://doi.org/10.1109/ICOE.2012.6409590","url":null,"abstract":"In this paper, we evaluate the performance of a burst retransmission method for an optical burst switched network with intermediate-node-initiation (INI) signaling technique. The proposed method tries to reduce the burst contention probability at the intermediate core nodes. We develop an analytical model to get the burst contention probability and burst loss probability for an optical burst switched network with intermediate-node-initiation signaling technique. The proposed method uses the optical burst retransmission method. We simulate the performance of the optical burst retransmission. Simulation results show that at low traffic loads the loss probability is low compared to the conventional burst retransmission in the OBS network. Result also show that the retransmission method for OBS network with intermediate-node-initiation signaling technique significantly reduces the burst loss probability.","PeriodicalId":142915,"journal":{"name":"2012 International Conference on Optical Engineering (ICOE)","volume":"91 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120882805","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 : 2012-07-26DOI: 10.1109/ICOE.2012.6409599
Sourabh Tiwari, V. Jain, S. Kar
The atmosphere affects the ground-to-satellite optical link characteristics. In Free Space Optical (FSO) communication it is important to minimize these atmospheric effects, so that efficient communication can take place. In this research paper different modulation schemes as such Pulse Position Modulation (PPM), Differential Pulse Position Modulation (DPPM) and Differential Amplitude Pulse Position Modulation (DAPPM) have been evaluated for atmospheric turbulence channel. It has been observed that DPPM and DAPPM are better bandwidth and power efficient in comparison to conventional modulation schemes OOK and PPM. So they can perform better in atmospheric turbulence channel. In our research paper these modulation schemes have been discussed and then the comparison of bit error rate performance of these modulation schemes has been made for ideal channel without any turbulence and for a practical channel with varying levels of turbulence. Two models log-normal and negative exponential channel model have been used to create weak and strong turbulence conditions. The BER performance with respect to SNR has been compared for PPM, DPPM and DAPPM for ground-to-satellite link.
{"title":"Performance evaluation of different Pulse Position Modulation schemes in atmospheric turbulence channel for ground-to-satellite optical communication","authors":"Sourabh Tiwari, V. Jain, S. Kar","doi":"10.1109/ICOE.2012.6409599","DOIUrl":"https://doi.org/10.1109/ICOE.2012.6409599","url":null,"abstract":"The atmosphere affects the ground-to-satellite optical link characteristics. In Free Space Optical (FSO) communication it is important to minimize these atmospheric effects, so that efficient communication can take place. In this research paper different modulation schemes as such Pulse Position Modulation (PPM), Differential Pulse Position Modulation (DPPM) and Differential Amplitude Pulse Position Modulation (DAPPM) have been evaluated for atmospheric turbulence channel. It has been observed that DPPM and DAPPM are better bandwidth and power efficient in comparison to conventional modulation schemes OOK and PPM. So they can perform better in atmospheric turbulence channel. In our research paper these modulation schemes have been discussed and then the comparison of bit error rate performance of these modulation schemes has been made for ideal channel without any turbulence and for a practical channel with varying levels of turbulence. Two models log-normal and negative exponential channel model have been used to create weak and strong turbulence conditions. The BER performance with respect to SNR has been compared for PPM, DPPM and DAPPM for ground-to-satellite link.","PeriodicalId":142915,"journal":{"name":"2012 International Conference on Optical Engineering (ICOE)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132165959","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 : 2012-07-26DOI: 10.1109/ICOE.2012.6409602
S. Divya, I. Sebastian, V. Nampoori, P. Radhakrishnan, A. Mujeeb
Linear as well as nonlinear absorption of TiO2-SiO2 nanocomposites prepared by sol gel process has been reported. To investigate the nonlinear properties, Z Scan technique was employed with 532 nm as the excitation wavelength followed by the calculation of the nonlinear optical constants. Z-scan experiments showed that when the excitation energy increased, the nonlinear absorption of the nanocomposites changed from reverse-saturable absorption to saturable absorption and then again back to reverse saturable absorption. Such a changeover in the sign of the nonlinearity is related to the interplay of exciton bleach and optical limiting mechanisms. The observed nonlinear absorption is found to be due to two photon absorption. The enhancement of the third-order nonlinearity in the composites can be due to the concentration of exciton oscillator strength.
{"title":"Power and composition dependent non linear optical switching of TiO2-SiO2 nano composites","authors":"S. Divya, I. Sebastian, V. Nampoori, P. Radhakrishnan, A. Mujeeb","doi":"10.1109/ICOE.2012.6409602","DOIUrl":"https://doi.org/10.1109/ICOE.2012.6409602","url":null,"abstract":"Linear as well as nonlinear absorption of TiO2-SiO2 nanocomposites prepared by sol gel process has been reported. To investigate the nonlinear properties, Z Scan technique was employed with 532 nm as the excitation wavelength followed by the calculation of the nonlinear optical constants. Z-scan experiments showed that when the excitation energy increased, the nonlinear absorption of the nanocomposites changed from reverse-saturable absorption to saturable absorption and then again back to reverse saturable absorption. Such a changeover in the sign of the nonlinearity is related to the interplay of exciton bleach and optical limiting mechanisms. The observed nonlinear absorption is found to be due to two photon absorption. The enhancement of the third-order nonlinearity in the composites can be due to the concentration of exciton oscillator strength.","PeriodicalId":142915,"journal":{"name":"2012 International Conference on Optical Engineering (ICOE)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129623548","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 : 2012-07-26DOI: 10.1109/ICOE.2012.6409575
S. Sebastian, S. Sooraj, A. Aaryan, J. Peter, V. P. N. Namboori, C. P. G. Vallaban, P. Radhakrishnan, M. Kailasnath
In the present work, we investigated the influence of laser ablated gold nanoparticles on the absorption and fluorescence spectra of Rhodamine 6G in Methyl Methacrylate. The absorption peak of Rhodamine 6G in Methyl Methacrylate has enhanced and the fluorescence peak has quenched in the presence of gold nanoparticles due to Fluorescence Resonance Energy Transfer. Also the wide absorption peak due to Surface Plasmon Resonance peak of gold nanoparticle in Methyl Methacrylate has split into two with a complete red shift in the presence of Rhodamine 6G.
{"title":"Impact of laser ablated gold nanoparticles on absorption and fluorescence of Rhodamine 6G in Methyl Methacrylate","authors":"S. Sebastian, S. Sooraj, A. Aaryan, J. Peter, V. P. N. Namboori, C. P. G. Vallaban, P. Radhakrishnan, M. Kailasnath","doi":"10.1109/ICOE.2012.6409575","DOIUrl":"https://doi.org/10.1109/ICOE.2012.6409575","url":null,"abstract":"In the present work, we investigated the influence of laser ablated gold nanoparticles on the absorption and fluorescence spectra of Rhodamine 6G in Methyl Methacrylate. The absorption peak of Rhodamine 6G in Methyl Methacrylate has enhanced and the fluorescence peak has quenched in the presence of gold nanoparticles due to Fluorescence Resonance Energy Transfer. Also the wide absorption peak due to Surface Plasmon Resonance peak of gold nanoparticle in Methyl Methacrylate has split into two with a complete red shift in the presence of Rhodamine 6G.","PeriodicalId":142915,"journal":{"name":"2012 International Conference on Optical Engineering (ICOE)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128679360","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 : 2012-07-26DOI: 10.1109/ICOE.2012.6409584
A. Shahini, H. Maleki, P. Khodashenas, K. Abbasian
The paper on hand shows an organic solar cell that combines the Shockley Queisser (SQ) theory with the classical diode theory to describe the microscopic processes which exist inside a cell. The photon recycling term is used to connect these two existing theories of solar cells. So this model can describe the interactions of electrons, holes and excitons and also reproduces the maximum SQ quantum efficiency. We show that how conduction band offset affect the short circuit current density and the operation modes of solar cell. Also we determine a relation that links the photovoltaic quantum efficiency and electroluminescence emission. We use this relation to calculate the quantum efficiency from electroluminescence (EL) and to compare with the directly calculated quantum efficiency.
{"title":"An organic solar cell: Investigation of band offset effect on transport and the validity of reciprocity theorem between electroluminescence and quantum efficiency","authors":"A. Shahini, H. Maleki, P. Khodashenas, K. Abbasian","doi":"10.1109/ICOE.2012.6409584","DOIUrl":"https://doi.org/10.1109/ICOE.2012.6409584","url":null,"abstract":"The paper on hand shows an organic solar cell that combines the Shockley Queisser (SQ) theory with the classical diode theory to describe the microscopic processes which exist inside a cell. The photon recycling term is used to connect these two existing theories of solar cells. So this model can describe the interactions of electrons, holes and excitons and also reproduces the maximum SQ quantum efficiency. We show that how conduction band offset affect the short circuit current density and the operation modes of solar cell. Also we determine a relation that links the photovoltaic quantum efficiency and electroluminescence emission. We use this relation to calculate the quantum efficiency from electroluminescence (EL) and to compare with the directly calculated quantum efficiency.","PeriodicalId":142915,"journal":{"name":"2012 International Conference on Optical Engineering (ICOE)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128729525","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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