The development of group-III nitride semiconductor technology continues to expand rapidly over the last two decades. The indium nitride (InN), gallium nitride (GaN) and aluminum nitride (AlN) compounds and their alloys are direct bandgap semiconductors with a wide bandgap range, spanning from infrared (IR) to deep-ultraviolet (UV), enabling their utilization in optoelectronic industry. The GaN-based light-emitting diode (LED) is already the commercial solution for efficient and energy saving lighting. Additionally, the physical properties of these materials such as the high critical electric field, the high saturation carrier velocity and the high thermal conductivity, make them promising candidates for replacing silicon (Si), and other wide-bandgap semiconductors such as silicon carbide (SiC) in power devices. More importantly, the polarization-induced twodimensional electron gas (2DEG), forming at the interfaces of these semiconductors, led to the fabrication of the GaN-based high electron mobility transistor (HEMT). This device is suitable for high power (HP) switching, power amplifiers and high frequency (HF) applications in the millimeter-wave range up to THz frequencies. As such, HEMTs are suitable for 5G communication systems, radars, satellites and a plethora of other related applications. Achieving the efficient GaN blue LED (Nobel Prize in Physics 2014), came as a result of (partially) solving several material issues of which, p-type GaN was of crucial importance. Since 1992, a lot of efforts have been dedicated on the understanding and overcoming of the limitations hindering efficient p-type conductivity and low hole mobility in metal-organic chemical vapor deposition (MOCVD) grown p-GaN. The limitations arise from the fact that magnesium (Mg) is the only efficient p-type dopant for GaN so far and only a very small percentage ∼ 2% of the incorporated Mg is active at room temperature. More limitations come from its solubility in GaN and the crystal quality deterioration and formation of inversion domains (IDs) at high doping levels. Free-hole concentrations in the low 1018 cm−3 range with mobilities at ∼ 10 cm2V−1s−1 demonstrate the state-of-art in MOCVD grown p-GaN, still leaving a wide window for improvement. Another intensively investigated topic is related to the aluminum gallium nitride (AlGaN)/ GaN HEMTs. High electron density and mobility of the 2DEG in the range of 1013 cm−2 and ∼ 2400 cm2V−1s−1 respectively, are reported. Interface engineering, addition of interlayers and backbarriers are only a few of the modifications introduced in the basic AlGaN/GaN HEMT structure in order to achieve the aforementioned values. Nevertheless, fundamental phenomena can still be revealed by special characterization techniques and provide a deeper understanding on the causal factors of the HEMT’s macroscopic properties. The main research results presented in this licentiate thesis are organized in three
{"title":"P-type and polarization doping of GaN in hot-wall MOCVD","authors":"A. Papamichail","doi":"10.3384/9789179292522","DOIUrl":"https://doi.org/10.3384/9789179292522","url":null,"abstract":"The development of group-III nitride semiconductor technology continues to expand rapidly over the last two decades. The indium nitride (InN), gallium nitride (GaN) and aluminum nitride (AlN) compounds and their alloys are direct bandgap semiconductors with a wide bandgap range, spanning from infrared (IR) to deep-ultraviolet (UV), enabling their utilization in optoelectronic industry. The GaN-based light-emitting diode (LED) is already the commercial solution for efficient and energy saving lighting. Additionally, the physical properties of these materials such as the high critical electric field, the high saturation carrier velocity and the high thermal conductivity, make them promising candidates for replacing silicon (Si), and other wide-bandgap semiconductors such as silicon carbide (SiC) in power devices. More importantly, the polarization-induced twodimensional electron gas (2DEG), forming at the interfaces of these semiconductors, led to the fabrication of the GaN-based high electron mobility transistor (HEMT). This device is suitable for high power (HP) switching, power amplifiers and high frequency (HF) applications in the millimeter-wave range up to THz frequencies. As such, HEMTs are suitable for 5G communication systems, radars, satellites and a plethora of other related applications. Achieving the efficient GaN blue LED (Nobel Prize in Physics 2014), came as a result of (partially) solving several material issues of which, p-type GaN was of crucial importance. Since 1992, a lot of efforts have been dedicated on the understanding and overcoming of the limitations hindering efficient p-type conductivity and low hole mobility in metal-organic chemical vapor deposition (MOCVD) grown p-GaN. The limitations arise from the fact that magnesium (Mg) is the only efficient p-type dopant for GaN so far and only a very small percentage ∼ 2% of the incorporated Mg is active at room temperature. More limitations come from its solubility in GaN and the crystal quality deterioration and formation of inversion domains (IDs) at high doping levels. Free-hole concentrations in the low 1018 cm−3 range with mobilities at ∼ 10 cm2V−1s−1 demonstrate the state-of-art in MOCVD grown p-GaN, still leaving a wide window for improvement. Another intensively investigated topic is related to the aluminum gallium nitride (AlGaN)/ GaN HEMTs. High electron density and mobility of the 2DEG in the range of 1013 cm−2 and ∼ 2400 cm2V−1s−1 respectively, are reported. Interface engineering, addition of interlayers and backbarriers are only a few of the modifications introduced in the basic AlGaN/GaN HEMT structure in order to achieve the aforementioned values. Nevertheless, fundamental phenomena can still be revealed by special characterization techniques and provide a deeper understanding on the causal factors of the HEMT’s macroscopic properties. The main research results presented in this licentiate thesis are organized in three","PeriodicalId":303036,"journal":{"name":"Linköping Studies in Science and Technology. Licentiate Thesis","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114584219","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}
{"title":"Epitaxial strategies for defect reduction in GaN for vertical power devices","authors":"Rosalia Delgado Carrascon","doi":"10.3384/9789179292478","DOIUrl":"https://doi.org/10.3384/9789179292478","url":null,"abstract":"","PeriodicalId":303036,"journal":{"name":"Linköping Studies in Science and Technology. Licentiate Thesis","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125481899","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}
In this era of rapid wireless technological advancements, wireless connectivity between humans, humans with machines, and machines with machines is gradually becoming an absolute necessity. The initial motivation for wireless connectivity was to enable voice communication between humans over a geographical area. Thanks to cellular communications advancements in the past decade, cellular wireless connectivity has become a global success, starting from 1G to the present generation 5G. However, the needs of humans often evolve with time, and now the world is witnessing an ever-growing demand for the internet with high data rates besides reliable voice communication. Current cellular networks suffer from non-uniform data rates across a cell, i.e., users at the cell center and the cell edges experience significant variations in signal-to-noise ratio, making the cellular technology less reliable to meet the future data demands. Moreover, cellular networks operating as cells, i.e., an access point (AP, the term we would use instead of base station) serving the users within its geographical location, cannot leverage the network’s total capacity without cooperation among APs of the neighboring cells. One potential solution is moving away from the cell to cell-free networks wherein all the APs will serve all the users within the geographical coverage area. Thus, there is a need for a paradigm shift in how cellular networks operate. Towards the goal mentioned above to fully leverage the network capacity, the Cell-Free Massive multiple-input-multiple-output (MIMO) technology is expected to be the next potential technology beyond 5G combining the benefits of Massive MIMO and cell-free distributed architectures. Distributed architectures require distributed signal processing algorithms, and also energy consumption of the network is crucial. Keeping in view the practical ease in deployment, we consider a sequentially connected CellFree Massive MIMO network called a “radio stripe”. In the first part of the thesis, we focus on developing an optimal sequential algorithm in the sense of mean-square-error (MSE) which has the same performance as that of centralized Cell-Free Massive MIMO implementation with the
{"title":"Cell-Free Massive MIMO: Distributed Signal Processing and Energy Efficiency","authors":"Z. H. Shaik","doi":"10.3384/9789179292232","DOIUrl":"https://doi.org/10.3384/9789179292232","url":null,"abstract":"In this era of rapid wireless technological advancements, wireless connectivity between humans, humans with machines, and machines with machines is gradually becoming an absolute necessity. The initial motivation for wireless connectivity was to enable voice communication between humans over a geographical area. Thanks to cellular communications advancements in the past decade, cellular wireless connectivity has become a global success, starting from 1G to the present generation 5G. However, the needs of humans often evolve with time, and now the world is witnessing an ever-growing demand for the internet with high data rates besides reliable voice communication. Current cellular networks suffer from non-uniform data rates across a cell, i.e., users at the cell center and the cell edges experience significant variations in signal-to-noise ratio, making the cellular technology less reliable to meet the future data demands. Moreover, cellular networks operating as cells, i.e., an access point (AP, the term we would use instead of base station) serving the users within its geographical location, cannot leverage the network’s total capacity without cooperation among APs of the neighboring cells. One potential solution is moving away from the cell to cell-free networks wherein all the APs will serve all the users within the geographical coverage area. Thus, there is a need for a paradigm shift in how cellular networks operate. Towards the goal mentioned above to fully leverage the network capacity, the Cell-Free Massive multiple-input-multiple-output (MIMO) technology is expected to be the next potential technology beyond 5G combining the benefits of Massive MIMO and cell-free distributed architectures. Distributed architectures require distributed signal processing algorithms, and also energy consumption of the network is crucial. Keeping in view the practical ease in deployment, we consider a sequentially connected CellFree Massive MIMO network called a “radio stripe”. In the first part of the thesis, we focus on developing an optimal sequential algorithm in the sense of mean-square-error (MSE) which has the same performance as that of centralized Cell-Free Massive MIMO implementation with the","PeriodicalId":303036,"journal":{"name":"Linköping Studies in Science and Technology. Licentiate Thesis","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117154688","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}
Daily life in modern society is highly dependent on many different materials and techniques for manipulating them, and the technological forefront is constantly pushed further by new discoveries. Hence, materials science is a very important field of research. The field of 2D materials is a rather young subfield within materials science, sprung from the realisation of the first 2D material graphene. 2D materials have, due to their 2D morphology, a very high surface-to-weight ratio, which makes them clearly attractive for applications where the material surface is an important characteristic, such as for energy storage and catalysis. The family of 2D materials called MXenes contrast to other 2D materials through the methods used to synthesise them. Traditionally, 2D materials are mechanically exfoliated from a 3D bulk structure in which the 2D sheets are only kept together by weak van der Waals forces, while MXenes are instead chemically exfoliated by selectively etching the A element from a member of the MAX phase family. A MAX phase is a hexagonal nanolaminated crystal structure on the formula Mn+1AXn, with n = 1 − 4, where the M indicates one or several transition metals, A stands for an “A element”, commonly a metalloid, and X stands for C or N. After etching away the A element from the MAX phase the Mn+1Xn-layers are left, making up the MXene. MXenes thus show an unusual structural and chemical diversity, and the composition spectra is even further expanded by atoms and small molecules, called surface terminations, attaching to the MXene surface upon etching. These terminations in turn also influence the properties of the MXene. Hence, the MXene family shows great potential for property tailoring towards many different applications. Besides MAX phases there are many other nanolaminated materials which can not be mechanically exfoliated like graphene, and the natural question arises: can other nanolaminated materials be etched into completely new 2D materials? This thesis is concerned with the so called MAB phases – a family of laminated materials similar to MAX phases, but with B instead of C or N – and their 2D derivatives from a compu-
现代社会的日常生活高度依赖于许多不同的材料和技术来操纵它们，新的发现不断推动着技术的前沿。因此，材料科学是一个非常重要的研究领域。二维材料领域是材料科学中一个相当年轻的分支领域，起源于第一个二维材料石墨烯的实现。二维材料由于其二维形态，具有非常高的表面重量比，这使得它们对于材料表面是重要特征的应用(例如能量存储和催化)具有明显的吸引力。被称为MXenes的二维材料家族通过合成它们的方法与其他二维材料形成对比。传统上，2D材料是通过机械方式从3D体结构中剥离出来的，其中2D薄片只能通过弱范德华力保持在一起，而MXenes是通过选择性地蚀刻MAX相族成员中的a元素来化学剥离的。MAX相是一种六角形纳米层状晶体结构，分子式为Mn+1AXn, n = 1−4，其中M表示一种或几种过渡金属，A表示“A元素”，通常为类金属，X表示C或n。在从MAX相中蚀刻掉A元素后，剩下Mn+ 1xn层，构成MXene。因此，MXene显示出不同寻常的结构和化学多样性，并且在蚀刻时附着在MXene表面的原子和小分子(称为表面末端)进一步扩展了组成光谱。这些终止反过来也会影响MXene的性质。因此，MXene系列显示了针对许多不同应用程序进行属性定制的巨大潜力。除了MAX相之外，还有许多其他的纳米层化材料不能像石墨烯那样机械剥离，自然就产生了一个问题:其他纳米层化材料能否蚀刻成全新的二维材料?本论文关注所谓的MAB相-一种类似MAX相的层压材料家族，但用B代替C或N -以及它们的二维衍生物
{"title":"A Computational Venture into the Realm of Laminated Borides and their 2D Derivatives","authors":"P. Helmer","doi":"10.3384/9789179292294","DOIUrl":"https://doi.org/10.3384/9789179292294","url":null,"abstract":"Daily life in modern society is highly dependent on many different materials and techniques for manipulating them, and the technological forefront is constantly pushed further by new discoveries. Hence, materials science is a very important field of research. The field of 2D materials is a rather young subfield within materials science, sprung from the realisation of the first 2D material graphene. 2D materials have, due to their 2D morphology, a very high surface-to-weight ratio, which makes them clearly attractive for applications where the material surface is an important characteristic, such as for energy storage and catalysis. The family of 2D materials called MXenes contrast to other 2D materials through the methods used to synthesise them. Traditionally, 2D materials are mechanically exfoliated from a 3D bulk structure in which the 2D sheets are only kept together by weak van der Waals forces, while MXenes are instead chemically exfoliated by selectively etching the A element from a member of the MAX phase family. A MAX phase is a hexagonal nanolaminated crystal structure on the formula Mn+1AXn, with n = 1 − 4, where the M indicates one or several transition metals, A stands for an “A element”, commonly a metalloid, and X stands for C or N. After etching away the A element from the MAX phase the Mn+1Xn-layers are left, making up the MXene. MXenes thus show an unusual structural and chemical diversity, and the composition spectra is even further expanded by atoms and small molecules, called surface terminations, attaching to the MXene surface upon etching. These terminations in turn also influence the properties of the MXene. Hence, the MXene family shows great potential for property tailoring towards many different applications. Besides MAX phases there are many other nanolaminated materials which can not be mechanically exfoliated like graphene, and the natural question arises: can other nanolaminated materials be etched into completely new 2D materials? This thesis is concerned with the so called MAB phases – a family of laminated materials similar to MAX phases, but with B instead of C or N – and their 2D derivatives from a compu-","PeriodicalId":303036,"journal":{"name":"Linköping Studies in Science and Technology. Licentiate Thesis","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117067718","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}
The data traffic in wireless networks has grown tremendously over the past few decades and is ever-increasing. Moreover, there is an enormous demand for speed as well. Future wireless networks need to support three generic heterogeneous services: enhanced mobile broadband(eMBB), ultrareliable low latency communication (URLLC) and massive machine type communication (mMTC). Massive MIMO has shown to be a promising technology to meet the demands and is now an integral part of 5G networks. To get high data rates, ultra densification of the network by deploying more base stations in the same geographical area is considered. This led to an increase in inter-cell interference which limits the capacity of the network. To mitigate the inter-cell interference, distributed MIMO is advocated. Cell-free massive MIMO is a promising technology to improve the capacity of the network. It leverages all the benefits from ultra densification, massive MIMO, and distributed MIMO technologies and operates without cell boundaries. In this thesis, we study random access, extreme multiplexing capabilities, and synchronization aspects of distributed massive MIMO. In Paper A studies the activity detection in grant-free random access for mMTC in cell-free massive MIMO network. An algorithm is proposed for activity detection based on maximum likelihood detection and the results show that the macrodiversity gain provided by the cell-free architecture improves the activity detection performance compared to co-located architecture when the coverage area is large. RadioWeaves technology is a new wireless infrastructure devised for indoor applications leveraging the benefits of massive MIMO and cell-free massive MIMO. In Paper B, we study the extreme multiplexing capabilities of RadioWeaves which can provide high data rates with very low power. We observe that the RadioWeaves deployment can spatially separate users much better than a conventional co-located deployment, which outweighs the losses caused by grating lobes and thus saves a lot on transmit power. Paper C studies the synchronization aspect of distributed massive MIMO.
{"title":"Distributed Massive MIMO : Random Access, Extreme Multiplexing and Synchronization","authors":"Unnikrishnan Kunnath Ganesan","doi":"10.3384/9789179292218","DOIUrl":"https://doi.org/10.3384/9789179292218","url":null,"abstract":"The data traffic in wireless networks has grown tremendously over the past few decades and is ever-increasing. Moreover, there is an enormous demand for speed as well. Future wireless networks need to support three generic heterogeneous services: enhanced mobile broadband(eMBB), ultrareliable low latency communication (URLLC) and massive machine type communication (mMTC). Massive MIMO has shown to be a promising technology to meet the demands and is now an integral part of 5G networks. To get high data rates, ultra densification of the network by deploying more base stations in the same geographical area is considered. This led to an increase in inter-cell interference which limits the capacity of the network. To mitigate the inter-cell interference, distributed MIMO is advocated. Cell-free massive MIMO is a promising technology to improve the capacity of the network. It leverages all the benefits from ultra densification, massive MIMO, and distributed MIMO technologies and operates without cell boundaries. In this thesis, we study random access, extreme multiplexing capabilities, and synchronization aspects of distributed massive MIMO. In Paper A studies the activity detection in grant-free random access for mMTC in cell-free massive MIMO network. An algorithm is proposed for activity detection based on maximum likelihood detection and the results show that the macrodiversity gain provided by the cell-free architecture improves the activity detection performance compared to co-located architecture when the coverage area is large. RadioWeaves technology is a new wireless infrastructure devised for indoor applications leveraging the benefits of massive MIMO and cell-free massive MIMO. In Paper B, we study the extreme multiplexing capabilities of RadioWeaves which can provide high data rates with very low power. We observe that the RadioWeaves deployment can spatially separate users much better than a conventional co-located deployment, which outweighs the losses caused by grating lobes and thus saves a lot on transmit power. Paper C studies the synchronization aspect of distributed massive MIMO.","PeriodicalId":303036,"journal":{"name":"Linköping Studies in Science and Technology. Licentiate Thesis","volume":"519 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123127251","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}
{"title":"Catalytically active and corrosion resistant cobalt-based thin films","authors":"Clara Linder","doi":"10.3384/9789179292171","DOIUrl":"https://doi.org/10.3384/9789179292171","url":null,"abstract":"","PeriodicalId":303036,"journal":{"name":"Linköping Studies in Science and Technology. Licentiate Thesis","volume":"449 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125847000","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}
{"title":"Hardening of Carbon Steel by Water Impinging Jet Quenching Technique : Differential Cooling of Steel Sheets and Quenching of Cylindrical Bars","authors":"P. Romanov","doi":"10.3384/9789179291839","DOIUrl":"https://doi.org/10.3384/9789179291839","url":null,"abstract":"","PeriodicalId":303036,"journal":{"name":"Linköping Studies in Science and Technology. Licentiate Thesis","volume":"158 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134520637","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}
{"title":"On Configuration Systems in Product Development for Mass Customisation","authors":"L. Poot","doi":"10.3384/9789179291631","DOIUrl":"https://doi.org/10.3384/9789179291631","url":null,"abstract":"","PeriodicalId":303036,"journal":{"name":"Linköping Studies in Science and Technology. Licentiate Thesis","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123952243","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}
{"title":"On Joint State Estimation and Model Learning using Gaussian Process Approximations","authors":"Anton Kullberg","doi":"10.3384/9789179291426","DOIUrl":"https://doi.org/10.3384/9789179291426","url":null,"abstract":"","PeriodicalId":303036,"journal":{"name":"Linköping Studies in Science and Technology. Licentiate Thesis","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132419031","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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