Pub Date : 2021-08-13DOI: 10.1080/01611194.2021.1905734
Elonka Dunin, Magnus Ekhall, Konstantin Hamidullin, Nils Kopal, G. Lasry, Klaus Schmeh
Abstract The Playfair cipher is a well-known manual encryption method developed in the 19th century. Until 2018, known cryptanalysis techniques, with computer assistance, could solve non-keyword-based Playfair ciphertexts if they had at least 60 letters to work with. Shorter ciphertexts were effectively impossible to solve in the absence of a crib. In this article, we show how we introduced several improvements in these cryptanalysis methods, which made it possible to do much better. This resulted in the (unofficial) world record for the shortest Playfair message broken going down from 60 via 50, 40, 32, and 28 to 26 letters. The cryptanalysis techniques used include hill climbing, simulated annealing, tabu search, and plaintext-based dictionary attacks. For readers interested in improving the current record, we also provide unsolved Playfair challenges consisting of 24 and 22 letters.
{"title":"How we set new world records in breaking Playfair ciphertexts","authors":"Elonka Dunin, Magnus Ekhall, Konstantin Hamidullin, Nils Kopal, G. Lasry, Klaus Schmeh","doi":"10.1080/01611194.2021.1905734","DOIUrl":"https://doi.org/10.1080/01611194.2021.1905734","url":null,"abstract":"Abstract The Playfair cipher is a well-known manual encryption method developed in the 19th century. Until 2018, known cryptanalysis techniques, with computer assistance, could solve non-keyword-based Playfair ciphertexts if they had at least 60 letters to work with. Shorter ciphertexts were effectively impossible to solve in the absence of a crib. In this article, we show how we introduced several improvements in these cryptanalysis methods, which made it possible to do much better. This resulted in the (unofficial) world record for the shortest Playfair message broken going down from 60 via 50, 40, 32, and 28 to 26 letters. The cryptanalysis techniques used include hill climbing, simulated annealing, tabu search, and plaintext-based dictionary attacks. For readers interested in improving the current record, we also provide unsolved Playfair challenges consisting of 24 and 22 letters.","PeriodicalId":55202,"journal":{"name":"Cryptologia","volume":"46 1","pages":"302 - 322"},"PeriodicalIF":0.6,"publicationDate":"2021-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44733319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The security of block ciphers solely depends on the S-boxes used in their design. Hence, for a secure block cipher, S-boxes should be chosen very thoughtfully. n-ary quasigroups of different orders and for different values of n are being used to design various cryptographic primitives. In the literature, many algorithms based on the quasigroups have been proposed for the generation of S-boxes of order 4. However, in this article, we propose a general method for the construction of symmetric S-boxes of even order using ternary quasigroups of order 4 with certain properties. These S-boxes give strong resistance against linear, differential, algebraic, and DPA attacks and hence provide good cryptographic properties.
{"title":"Construction of cryptographically strong S-boxes from ternary quasigroups of order 4","authors":"Dimpy Chauhan, Indivar Gupta, Pooja Mishra, Rashmi Verma","doi":"10.1080/01611194.2021.1934915","DOIUrl":"https://doi.org/10.1080/01611194.2021.1934915","url":null,"abstract":"Abstract The security of block ciphers solely depends on the S-boxes used in their design. Hence, for a secure block cipher, S-boxes should be chosen very thoughtfully. n-ary quasigroups of different orders and for different values of n are being used to design various cryptographic primitives. In the literature, many algorithms based on the quasigroups have been proposed for the generation of S-boxes of order 4. However, in this article, we propose a general method for the construction of symmetric S-boxes of even order using ternary quasigroups of order 4 with certain properties. These S-boxes give strong resistance against linear, differential, algebraic, and DPA attacks and hence provide good cryptographic properties.","PeriodicalId":55202,"journal":{"name":"Cryptologia","volume":"46 1","pages":"525 - 551"},"PeriodicalIF":0.6,"publicationDate":"2021-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/01611194.2021.1934915","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46704637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-20DOI: 10.1080/01611194.2021.1914775
P. Mishra, S. Ramola
Abstract The period of a binary sequence generated by feedback with carry shift register (FCSR) depends on the connection integer (q) of the register. We define FCSR primes as primes generating maximum possible period sequences when used as connection integer of an FCSR. Hence, to design good FCSR pseudorandom generators, one needs suitable feedback primes. The authors of this article study some properties about these primes and give algorithms to generate some of them. The first algorithm is somewhat straightforward and is based on the criterion given in Arnault and Berger. We propose two new algorithms for the efficient generation of FCSR primes. Comparison between these algorithms, supported by experimental and analytical results is presented. Further, we address the question of quantification of such primes and derive some explicit bounds.
{"title":"FCSR connection integers: efficient generation, testing and counting","authors":"P. Mishra, S. Ramola","doi":"10.1080/01611194.2021.1914775","DOIUrl":"https://doi.org/10.1080/01611194.2021.1914775","url":null,"abstract":"Abstract The period of a binary sequence generated by feedback with carry shift register (FCSR) depends on the connection integer (q) of the register. We define FCSR primes as primes generating maximum possible period sequences when used as connection integer of an FCSR. Hence, to design good FCSR pseudorandom generators, one needs suitable feedback primes. The authors of this article study some properties about these primes and give algorithms to generate some of them. The first algorithm is somewhat straightforward and is based on the criterion given in Arnault and Berger. We propose two new algorithms for the efficient generation of FCSR primes. Comparison between these algorithms, supported by experimental and analytical results is presented. Further, we address the question of quantification of such primes and derive some explicit bounds.","PeriodicalId":55202,"journal":{"name":"Cryptologia","volume":"46 1","pages":"439 - 460"},"PeriodicalIF":0.6,"publicationDate":"2021-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/01611194.2021.1914775","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43367190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-20DOI: 10.1080/01611194.2021.1919944
François Parmentier
The Voynich Manuscript is a medieval book, whose text has continuously resisted decoding efforts for more than a century. First, propositions are made to insure a good overall quality of research about this manuscript. Next, two common assumptions, correspondingly about the manuscript writing system and the presence of labels, are questioned. As a result, a certain number of irregular forms of letters are pointed out and tentatively explained; and labels are found to be sometimes widespread words or refer to different objects (plants, stars…). Theoretical implications of such empirical findings are discussed, and call into question the validity of natural language hypothesis.
{"title":"Deciphering the Voynich manuscript: propositions to unlock research","authors":"François Parmentier","doi":"10.1080/01611194.2021.1919944","DOIUrl":"https://doi.org/10.1080/01611194.2021.1919944","url":null,"abstract":"The Voynich Manuscript is a medieval book, whose text has continuously resisted decoding efforts for more than a century. First, propositions are made to insure a good overall quality of research about this manuscript. Next, two common assumptions, correspondingly about the manuscript writing system and the presence of labels, are questioned. As a result, a certain number of irregular forms of letters are pointed out and tentatively explained; and labels are found to be sometimes widespread words or refer to different objects (plants, stars…). Theoretical implications of such empirical findings are discussed, and call into question the validity of natural language hypothesis.","PeriodicalId":55202,"journal":{"name":"Cryptologia","volume":"46 1","pages":"461 - 484"},"PeriodicalIF":0.6,"publicationDate":"2021-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/01611194.2021.1919944","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49601108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-04DOI: 10.1080/01611194.2021.1921072
Robert J. Hanyok
Abstract At the end of World War II, the Allied Cryptologic agencies in the U.S.A. and U.K. realized that valuable intelligence about Axis codebreaking and other analytic methods, as well as knowledge about Axis cryptography, could be lost, either through destruction or capture by the Soviet Union. A special organization, known as the Target Intelligence Committee (TICOM), was organized to retrieve this information. Special teams followed Allied forces into former Axis territory, gathered captured records and equipment and interrogated Axis cryptographers about their methods, successes, and failures. In the United States, this material was retained by the National Security Agency until major releases of WWII records to the National Archives, beginning in the mid-1990s and continuing for approximately another 20 years. TICOM records constitute a critical resource to understanding the dynamics of the struggle between those charged with protecting communications, the secrets they hold, and those with the mandate to discover those secrets.
{"title":"Sources and methods: Searching for cryptologic records in the findings of post-World War II allied technical surveys and commissions","authors":"Robert J. Hanyok","doi":"10.1080/01611194.2021.1921072","DOIUrl":"https://doi.org/10.1080/01611194.2021.1921072","url":null,"abstract":"Abstract At the end of World War II, the Allied Cryptologic agencies in the U.S.A. and U.K. realized that valuable intelligence about Axis codebreaking and other analytic methods, as well as knowledge about Axis cryptography, could be lost, either through destruction or capture by the Soviet Union. A special organization, known as the Target Intelligence Committee (TICOM), was organized to retrieve this information. Special teams followed Allied forces into former Axis territory, gathered captured records and equipment and interrogated Axis cryptographers about their methods, successes, and failures. In the United States, this material was retained by the National Security Agency until major releases of WWII records to the National Archives, beginning in the mid-1990s and continuing for approximately another 20 years. TICOM records constitute a critical resource to understanding the dynamics of the struggle between those charged with protecting communications, the secrets they hold, and those with the mandate to discover those secrets.","PeriodicalId":55202,"journal":{"name":"Cryptologia","volume":"45 1","pages":"371 - 378"},"PeriodicalIF":0.6,"publicationDate":"2021-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/01611194.2021.1921072","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47137828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-04DOI: 10.1080/01611194.2021.1935363
Frode Weierud
Ralph passed away in his sleep on Friday 9 April 2021 at the age of 87. Only days before he was in contact with his friends, busy writing up some of his research for yet another publication and reviewing articles of his colleagues. The news of his untimely death therefore came as a great shock to us all. Ralph was born in Belfast in Northern Ireland on 14 October 1933. His parents were Robert Todd Erskine, a Belfast businessman, and Mary Edith Erskine, n ee Motherwell. He was one of four children: Robert Alan, who died in early childhood, Ann, who passed away in 2020, and Ruth. In 1941, at the age of eight, he started at Portora Royal School, a boarding school in Enniskillen 130 km west of Belfast, which has educated many well-known Irishmen among them Samuel Becket and Oscar Wilde. Boarding school must have been a challenging experience for a boy of that age, especially when being rather shy. In September 1947 he left for Campbell College in Belfast, a grammar school for boys now open to both day and boarding students. In 1947 it was primarily a boarding school and Ralph was lodged in Yate’s house. In his teens he contracted tuberculosis a disease not so uncommon in those days. This resulted in Ralph spending a year and a half in the hospital, something that must have been a harrowing experience at such a young age. He later expressed that he considered himself lucky because many in his hospital ward did not survive. However, the illness had its impact on his life. Many things, such as running to catch the bus, he was not able to do; it was not until his late twenties that such physical exercise again became possible. Ralph had a keen intellect, and he did well in school. In July 1949 he left Campbell College to enter Queen’s University in Belfast to study law. He graduated in 1955 with a very good law degree, LLB. On 1 July 1957 Ralph
{"title":"In memoriam: Thomas Ralph Erskine CB (1933 – 2021)","authors":"Frode Weierud","doi":"10.1080/01611194.2021.1935363","DOIUrl":"https://doi.org/10.1080/01611194.2021.1935363","url":null,"abstract":"Ralph passed away in his sleep on Friday 9 April 2021 at the age of 87. Only days before he was in contact with his friends, busy writing up some of his research for yet another publication and reviewing articles of his colleagues. The news of his untimely death therefore came as a great shock to us all. Ralph was born in Belfast in Northern Ireland on 14 October 1933. His parents were Robert Todd Erskine, a Belfast businessman, and Mary Edith Erskine, n ee Motherwell. He was one of four children: Robert Alan, who died in early childhood, Ann, who passed away in 2020, and Ruth. In 1941, at the age of eight, he started at Portora Royal School, a boarding school in Enniskillen 130 km west of Belfast, which has educated many well-known Irishmen among them Samuel Becket and Oscar Wilde. Boarding school must have been a challenging experience for a boy of that age, especially when being rather shy. In September 1947 he left for Campbell College in Belfast, a grammar school for boys now open to both day and boarding students. In 1947 it was primarily a boarding school and Ralph was lodged in Yate’s house. In his teens he contracted tuberculosis a disease not so uncommon in those days. This resulted in Ralph spending a year and a half in the hospital, something that must have been a harrowing experience at such a young age. He later expressed that he considered himself lucky because many in his hospital ward did not survive. However, the illness had its impact on his life. Many things, such as running to catch the bus, he was not able to do; it was not until his late twenties that such physical exercise again became possible. Ralph had a keen intellect, and he did well in school. In July 1949 he left Campbell College to enter Queen’s University in Belfast to study law. He graduated in 1955 with a very good law degree, LLB. On 1 July 1957 Ralph","PeriodicalId":55202,"journal":{"name":"Cryptologia","volume":"45 1","pages":"289 - 308"},"PeriodicalIF":0.6,"publicationDate":"2021-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/01611194.2021.1935363","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45892986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-28DOI: 10.1080/01611194.2021.1938297
R. J. Morgan
Abstract Rudyard Kipling asserted that he had included a ‘cryptogram’ in his book ‘Rewards and Fairies’ (1910). This has so far gone unsolved, and indeed undetected. I present the known information.
{"title":"Rudyard Kipling’s unsolved cryptogram","authors":"R. J. Morgan","doi":"10.1080/01611194.2021.1938297","DOIUrl":"https://doi.org/10.1080/01611194.2021.1938297","url":null,"abstract":"Abstract Rudyard Kipling asserted that he had included a ‘cryptogram’ in his book ‘Rewards and Fairies’ (1910). This has so far gone unsolved, and indeed undetected. I present the known information.","PeriodicalId":55202,"journal":{"name":"Cryptologia","volume":"46 1","pages":"485 - 497"},"PeriodicalIF":0.6,"publicationDate":"2021-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/01611194.2021.1938297","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46422454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-21DOI: 10.1080/01611194.2021.1911876
D. Chaum, Mario Yaksetig, A. Sherman, Joeri de Ruiter
Abstract We present and analyze User Discovery with Minimal information disclosure (UDM), a new protocol for user discovery in anonymous communication systems that minimizes the information disclosed to the system and users. UDM solves the following user-discovery problem. User Alice wishes to communicate with Bob over an anonymous communication system, such as cMix or Tor. Initially, each party knows each other’s public contact identifier (e.g., email address or phone number), but neither knows the other’s private platform identifier in the communication system. If both parties wish to communicate with each other, UDM enables them to establish a shared secret and learn each other’s private platform identifier. Unlike existing systems, including those based on private set intersection, UDM learns nothing about the social contacts of the users, is not vulnerable to off-line dictionary attacks that expose contact lists, does not reveal platform identifiers to users without the owner’s explicit permission, and enjoys low computation and communication complexity. Using the anonymous communication system, each pair of users who wish to communicate with each other uploads to the user-discovery system their private platform identifier, encrypted with a key derived from their shared secret. Indexing their request by a cryptographic tag derived from their shared secret, each user can then download each other’s encrypted private platform identifier. In doing so, UDM uses an untrusted user-discovery system, which processes and stores only public information or values encrypted with keys it does not know. Therefore, from the data values it processes, UDM cannot learn any information about the social contacts of its users.
{"title":"UDM: Private user discovery with minimal information disclosure","authors":"D. Chaum, Mario Yaksetig, A. Sherman, Joeri de Ruiter","doi":"10.1080/01611194.2021.1911876","DOIUrl":"https://doi.org/10.1080/01611194.2021.1911876","url":null,"abstract":"Abstract We present and analyze User Discovery with Minimal information disclosure (UDM), a new protocol for user discovery in anonymous communication systems that minimizes the information disclosed to the system and users. UDM solves the following user-discovery problem. User Alice wishes to communicate with Bob over an anonymous communication system, such as cMix or Tor. Initially, each party knows each other’s public contact identifier (e.g., email address or phone number), but neither knows the other’s private platform identifier in the communication system. If both parties wish to communicate with each other, UDM enables them to establish a shared secret and learn each other’s private platform identifier. Unlike existing systems, including those based on private set intersection, UDM learns nothing about the social contacts of the users, is not vulnerable to off-line dictionary attacks that expose contact lists, does not reveal platform identifiers to users without the owner’s explicit permission, and enjoys low computation and communication complexity. Using the anonymous communication system, each pair of users who wish to communicate with each other uploads to the user-discovery system their private platform identifier, encrypted with a key derived from their shared secret. Indexing their request by a cryptographic tag derived from their shared secret, each user can then download each other’s encrypted private platform identifier. In doing so, UDM uses an untrusted user-discovery system, which processes and stores only public information or values encrypted with keys it does not know. Therefore, from the data values it processes, UDM cannot learn any information about the social contacts of its users.","PeriodicalId":55202,"journal":{"name":"Cryptologia","volume":"46 1","pages":"347 - 379"},"PeriodicalIF":0.6,"publicationDate":"2021-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/01611194.2021.1911876","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41649670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-07DOI: 10.1080/01611194.2021.1929567
B. R. Smoot
Abstract Recent years have seen a surge in interest in writing (and reading) biographies of renowned cryptologists. This article looks at the surge and provides suggestions for those wishing to research and write both short form and long form biographies and those who wish to know more about a cryptologist in their family.
{"title":"Sources and methods for cryptologic history: researching individuals (and the biography boom)","authors":"B. R. Smoot","doi":"10.1080/01611194.2021.1929567","DOIUrl":"https://doi.org/10.1080/01611194.2021.1929567","url":null,"abstract":"Abstract Recent years have seen a surge in interest in writing (and reading) biographies of renowned cryptologists. This article looks at the surge and provides suggestions for those wishing to research and write both short form and long form biographies and those who wish to know more about a cryptologist in their family.","PeriodicalId":55202,"journal":{"name":"Cryptologia","volume":"45 1","pages":"465 - 473"},"PeriodicalIF":0.6,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/01611194.2021.1929567","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45344871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-07DOI: 10.1080/01611194.2021.1918801
Anna Lehofer
Abstract This study examines whether hierarchical clustering can be used efficiently on homophonic substitution ciphers from the early modern age. The methodology was first tested on artificial homophonic ciphers based on historical corpora in 4 different languages. This investigation established that the decryptability of homophonic substitution letters does not depend on the plain text language, and it is effective if the text length goes beyond the unicity point. Finally the examination of original homophonic substitution cipher – cipher-key pairs followed in 4 languages. It determined that the method is applicable to original historical encrypted documents as well.
{"title":"Applying hierarchical clustering to homophonic substitution ciphers using historical corpora","authors":"Anna Lehofer","doi":"10.1080/01611194.2021.1918801","DOIUrl":"https://doi.org/10.1080/01611194.2021.1918801","url":null,"abstract":"Abstract This study examines whether hierarchical clustering can be used efficiently on homophonic substitution ciphers from the early modern age. The methodology was first tested on artificial homophonic ciphers based on historical corpora in 4 different languages. This investigation established that the decryptability of homophonic substitution letters does not depend on the plain text language, and it is effective if the text length goes beyond the unicity point. Finally the examination of original homophonic substitution cipher – cipher-key pairs followed in 4 languages. It determined that the method is applicable to original historical encrypted documents as well.","PeriodicalId":55202,"journal":{"name":"Cryptologia","volume":"46 1","pages":"422 - 438"},"PeriodicalIF":0.6,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/01611194.2021.1918801","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44067778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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