Several degree-based topological indices have a vital role in the inspection of the chemical properties of various chemical networks. Hex-derived networks, made up of hexagonal mesh networks, have wide applications in the fields of technology, pharmacy and physical sciences. In this research work, we focus on different hex-derived networks of the third type of dimension n and their subdivisions. The Nirmala indices (such as the Nirmala index, the first inverse Nirmala index and the second inverse Nirmala index) are newly introduced degree-based topological indices. Here, we compute the values of these Nirmala indices for the above networks under consideration by operating their standard mathematical formulas and the M-polynomial based method. In addition, we plot the Nirmala indices of the networks and their subdivisions in different dimensions for the purpose of comparative studies among them. The results acquired are helpful in demonstrating the structural properties of considered hex-derived networks and their subdivisions. Also, it may influence the researchers for comparative based studies of the structure and their subdivisions in the sense of the Nirmala indices.
一些基于度数的拓扑指数在检测各种化学网络的化学特性方面发挥着重要作用。由六边形网状网络组成的六边形衍生网络在技术、制药和物理科学领域有着广泛的应用。在这项研究工作中,我们重点研究第三类维数为 n 的不同六边形衍生网络及其细分。尼玛拉指数(如尼玛拉指数、第一逆尼玛拉指数和第二逆尼玛拉指数)是新引入的基于度数的拓扑指数。在此,我们通过标准数学公式和基于 M 多项式的方法计算出上述网络的这些尼玛拉指数值。此外,我们还绘制了这些网络及其细分网络在不同维度上的尼玛拉指数,以便对它们进行比较研究。所获得的结果有助于展示所考虑的六边形衍生网络及其细分网络的结构特性。此外,它还可能影响研究人员在尼玛拉指数的意义上对结构及其细分进行基于比较的研究。
{"title":"On Nirmala Indices of Some Hex-derived Networks of Type Three and Their Subdivision Networks","authors":"S. Rai, Shibsankar Das","doi":"10.7561/SACS.2023.2.193","DOIUrl":"https://doi.org/10.7561/SACS.2023.2.193","url":null,"abstract":"Several degree-based topological indices have a vital role in the inspection of the chemical properties of various chemical networks. Hex-derived networks, made up of hexagonal mesh networks, have wide applications in the fields of technology, pharmacy and physical sciences. In this research work, we focus on different hex-derived networks of the third type of dimension n and their subdivisions. The Nirmala indices (such as the Nirmala index, the first inverse Nirmala index and the second inverse Nirmala index) are newly introduced degree-based topological indices. Here, we compute the values of these Nirmala indices for the above networks under consideration by operating their standard mathematical formulas and the M-polynomial based method. In addition, we plot the Nirmala indices of the networks and their subdivisions in different dimensions for the purpose of comparative studies among them. The results acquired are helpful in demonstrating the structural properties of considered hex-derived networks and their subdivisions. Also, it may influence the researchers for comparative based studies of the structure and their subdivisions in the sense of the Nirmala indices.","PeriodicalId":394919,"journal":{"name":"Sci. Ann. Comput. Sci.","volume":"82 1","pages":"193-242"},"PeriodicalIF":0.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139170529","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}
We define the notion of k-safe infinitary series over idempotent ordered totally generalized product omega-valuation monoids that satisfy specific properties. For each element k of the underlying structure (different from the neutral elements of the additive, and the multiplicative operation) we determine two syntactic fragments of the weighted LTL with the property that the semantics of the formulas in these fragments are k-safe infinitary series. For specific idempotent ordered totally generalized product omega-valuation monoids we provide algorithms that given a weighted Buchi automaton and a weighted LTL formula in these fragments, decide whether the behavior of the automaton coincides with the semantics of the formula.
我们定义了在满足特定属性的幂级数上的 k 安全无穷级数概念。对于底层结构的每个元素 k(不同于加法运算和乘法运算的中性元素),我们确定了加权 LTL 的两个语法片段,这些片段中公式的语义具有 k 安全无穷级数的特性。对于特定的幂等有序完全广义积ω-估值单体,我们提供了给定加权布基自动机和这些片段中的加权 LTL 公式的算法,以判定自动机的行为是否与公式的语义相吻合。
{"title":"Describing weighted safety with weighted LTL over product omega-valuation monoids","authors":"Eleni Mandrali","doi":"10.7561/SACS.2023.2.93","DOIUrl":"https://doi.org/10.7561/SACS.2023.2.93","url":null,"abstract":"We define the notion of k-safe infinitary series over idempotent ordered totally generalized product omega-valuation monoids that satisfy specific properties. For each element k of the underlying structure (different from the neutral elements of the additive, and the multiplicative operation) we determine two syntactic fragments of the weighted LTL with the property that the semantics of the formulas in these fragments are k-safe infinitary series. For specific idempotent ordered totally generalized product omega-valuation monoids we provide algorithms that given a weighted Buchi automaton and a weighted LTL formula in these fragments, decide whether the behavior of the automaton coincides with the semantics of the formula.","PeriodicalId":394919,"journal":{"name":"Sci. Ann. Comput. Sci.","volume":"100 11","pages":"93-157"},"PeriodicalIF":0.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138954224","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 research on formal languages and their algebraic relationships were among the topics that brought visibility to Romania in the field of computer science in the 1970’s. Alexandru Ioan Cuza University of Iași was known by its researchers and teachers in these topics.
形式语言及其代数关系的研究是20世纪70年代罗马尼亚在计算机科学领域引人注目的主题之一。Iași的Alexandru Ioan Cuza大学以其研究人员和教师在这些主题方面而闻名。
{"title":"A Teacher of Great Strengths","authors":"Gabriel Ciobanu","doi":"10.7561/sacs.2023.1.1","DOIUrl":"https://doi.org/10.7561/sacs.2023.1.1","url":null,"abstract":"The research on formal languages and their algebraic relationships were among the topics that brought visibility to Romania in the field of computer science in the 1970’s. Alexandru Ioan Cuza University of Iași was known by its researchers and teachers in these topics.","PeriodicalId":394919,"journal":{"name":"Sci. Ann. Comput. Sci.","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124165650","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}
Shrinkage estimators modify classical statistical estimators by scaling them towards zero in order to decrease their prediction error. We propose shrinkage estimators for linear regression models which explicitly take into account the presence of the intercept term, shrinking it independently from other coefficients. This is different from current shrinkage estimators, which treat the intercept just as an ordinary regression coefficient. We demonstrate that the proposed approach brings systematic improvements in prediction accuracy if the true intercept term differs in magnitude from other coefficients, which is often the case in practice. We then generalize the approach to uplift regression which aims to predict the causal effect of a specific action on an individual with given characteristics. In this case the proposed estimators improve prediction accuracy over previously proposed shrinkage estimators and achieve impressive performance gains over original models.
{"title":"Shrinkage Estimators for the Intercept in Linear and Uplift Regression","authors":"S. Jaroszewicz, Krzysztof Rudas","doi":"10.7561/sacs.2023.1.35","DOIUrl":"https://doi.org/10.7561/sacs.2023.1.35","url":null,"abstract":"Shrinkage estimators modify classical statistical estimators by scaling them towards zero in order to decrease their prediction error. We propose shrinkage estimators for linear regression models which explicitly take into account the presence of the intercept term, shrinking it independently from other coefficients. This is different from current shrinkage estimators, which treat the intercept just as an ordinary regression coefficient. We demonstrate that the proposed approach brings systematic improvements in prediction accuracy if the true intercept term differs in magnitude from other coefficients, which is often the case in practice. We then generalize the approach to uplift regression which aims to predict the causal effect of a specific action on an individual with given characteristics. In this case the proposed estimators improve prediction accuracy over previously proposed shrinkage estimators and achieve impressive performance gains over original models.","PeriodicalId":394919,"journal":{"name":"Sci. Ann. Comput. Sci.","volume":"365 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115471839","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 tree width of an alternating finite automaton (AFA) measures the parallelism in all computations of the AFA on a given input. The maximal existential (respectively, universal) width of an AFA A on string w measures the maximal number of existential choices (respectively, of parallel universal branches) in one computation of A on w. We give polynomial time algorithms deciding finiteness of an AFA’s tree width and maximal universal width. Also we give a polynomial time algorithm that for an AFA A with finite maximal universal width decides whether or not the maximal existential width of A is finite. Finiteness of maximal existential width is decidable in the general case but the algorithm uses exponential time. Additionally, we establish necessary and sufficient conditions for an AFA to have exponential tree width growth rate, as well as sufficient conditions for an AFA to have exponential maximal existential width or exponential maximal universal width.
{"title":"Maximal Existential and Universal Width","authors":"Casey Keeler, K. Salomaa","doi":"10.7561/sacs.2023.1.53","DOIUrl":"https://doi.org/10.7561/sacs.2023.1.53","url":null,"abstract":"The tree width of an alternating finite automaton (AFA) measures the parallelism in all computations of the AFA on a given input. The maximal existential (respectively, universal) width of an AFA A on string w measures the maximal number of existential choices (respectively, of parallel universal branches) in one computation of A on w. We give polynomial time algorithms deciding finiteness of an AFA’s tree width and maximal universal width. Also we give a polynomial time algorithm that for an AFA A with finite maximal universal width decides whether or not the maximal existential width of A is finite. Finiteness of maximal existential width is decidable in the general case but the algorithm uses exponential time. Additionally, we establish necessary and sufficient conditions for an AFA to have exponential tree width growth rate, as well as sufficient conditions for an AFA to have exponential maximal existential width or exponential maximal universal width.","PeriodicalId":394919,"journal":{"name":"Sci. Ann. Comput. Sci.","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129018619","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}
A centralizing monoid M is a set of unary operations which commute with some set F of operations. Here, F is called a witness of M . On a 3-element set, a centralizing monoid is maximal if and only if it has a constant operation or a majority minimal operation as its witness. In this paper, we take one such majority operation, which corresponds to a maximal centralizing monoid, on a 3-element set and obtain its generalization, called mb , on a k-element set for any k >= 3. We explicitly describe the centralizing monoid M(mb ) with mb as its witness and then prove that it is not maximal if k > 3, contrary to the case for k = 3.
{"title":"A Study on Centralizing Monoids with Majority Operation Witnesses","authors":"Hajime Machida","doi":"10.7561/sacs.2023.1.79","DOIUrl":"https://doi.org/10.7561/sacs.2023.1.79","url":null,"abstract":"A centralizing monoid M is a set of unary operations which commute with some set F of operations. Here, F is called a witness of M . On a 3-element set, a centralizing monoid is maximal if and only if it has a constant operation or a majority minimal operation as its witness. In this paper, we take one such majority operation, which corresponds to a maximal centralizing monoid, on a 3-element set and obtain its generalization, called mb , on a k-element set for any k >= 3. We explicitly describe the centralizing monoid M(mb ) with mb as its witness and then prove that it is not maximal if k > 3, contrary to the case for k = 3.","PeriodicalId":394919,"journal":{"name":"Sci. Ann. Comput. Sci.","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132528079","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 reticulation L(R) of a commutative ring R was introduced by Joyal in 1975, then the theory was developed by Simmons in a remarkable paper published in 1980. L(R) is a bounded distributive algebra whose main property is that the Zariski prime spectrum Spec(R) of R and the Stone prime spectrum SpecId (L(R)) of L(R) are homeomorphic. The construction of the lattice L(R) was generalized by Belluce for each unital ring R and the reticulation was defined by axioms. In a recent paper we generalized the Belluce construction for algebras in a semidegenerate congruence-modular variety V. For any algebra A ∈ V we defined a bounded distributive lattice L(A), but in general the prime spectrum Spec(A) of A is not homeomorphic with the prime spectrum SpecId (L(A)). We introduced the quasi-commutative algebras in the variety V (as a generalization of Belluce’s quasi-commutative rings) and proved that for any algebra A ∈ V, the spectra Spec(A) and SpecId (L(A)) are homeomorphic. In this paper we define the reticulation A ∈ V by four axioms and prove that any two reticulations of A are isomorphic lattices. By using the uniqueness of reticulation and other results from the mentioned paper, we obtain a characterization theorem for the algebras A ∈ V that admit a reticulation: A is quasi-commutative if and only if A admits a reticulation. This result is a universal algebra generalization of the following Belluce theorem: a ring R is quasi-commutative if and only if R admits a reticulation. Another subject treated in this paper is the spectral closure of the prime spectrum Spec(A) of an algebra A ∈ V, a notion that generalizes the Belluce spectral closure of the prime spectrum of a ring.
{"title":"Semidegenerate Congruence-modular Algebras Admitting a Reticulation","authors":"G. Georgescu","doi":"10.7561/sacs.2023.1.5","DOIUrl":"https://doi.org/10.7561/sacs.2023.1.5","url":null,"abstract":"The reticulation L(R) of a commutative ring R was introduced by Joyal in 1975, then the theory was developed by Simmons in a remarkable paper published in 1980. L(R) is a bounded distributive algebra whose main property is that the Zariski prime spectrum Spec(R) of R and the Stone prime spectrum SpecId (L(R)) of L(R) are homeomorphic. The construction of the lattice L(R) was generalized by Belluce for each unital ring R and the reticulation was defined by axioms. In a recent paper we generalized the Belluce construction for algebras in a semidegenerate congruence-modular variety V. For any algebra A ∈ V we defined a bounded distributive lattice L(A), but in general the prime spectrum Spec(A) of A is not homeomorphic with the prime spectrum SpecId (L(A)). We introduced the quasi-commutative algebras in the variety V (as a generalization of Belluce’s quasi-commutative rings) and proved that for any algebra A ∈ V, the spectra Spec(A) and SpecId (L(A)) are homeomorphic. In this paper we define the reticulation A ∈ V by four axioms and prove that any two reticulations of A are isomorphic lattices. By using the uniqueness of reticulation and other results from the mentioned paper, we obtain a characterization theorem for the algebras A ∈ V that admit a reticulation: A is quasi-commutative if and only if A admits a reticulation. This result is a universal algebra generalization of the following Belluce theorem: a ring R is quasi-commutative if and only if R admits a reticulation. Another subject treated in this paper is the spectral closure of the prime spectrum Spec(A) of an algebra A ∈ V, a notion that generalizes the Belluce spectral closure of the prime spectrum of a ring.","PeriodicalId":394919,"journal":{"name":"Sci. Ann. Comput. Sci.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131165500","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 main idea of multi-frame super resolution (SR) algorithms is to recover a single high-resolution image from a sequence of low resolution ones of the same object. The success of the SR approaches is often related to a well registration and restoration steps. Therefore, we propose a new approach based on fluid image registration and we use a second order partial differential equation (PDE) to treat both the registration and restoration steps that guarantees the success of SR algorithms. Since the registration step is usually a variational ill-posed model, a mathematical study is needed to check the existence of the solution to the regularized problem. Thus, we prove the existence and uniqueness of the well posed fluid image registration and assure also the existence of the used second order PDE in the restoration step. The results show that the proposed method is competitive with the existing methods.
{"title":"An Enhanced Fluid Registration for Image Multi-Frame Super Resolution","authors":"A. Laghrib, A. Hadri, M. Hakim","doi":"10.7561/SACS.2022.2.255","DOIUrl":"https://doi.org/10.7561/SACS.2022.2.255","url":null,"abstract":"The main idea of multi-frame super resolution (SR) algorithms is to recover a single high-resolution image from a sequence of low resolution ones of the same object. The success of the SR approaches is often related to a well registration and restoration steps. Therefore, we propose a new approach based on fluid image registration and we use a second order partial differential equation (PDE) to treat both the registration and restoration steps that guarantees the success of SR algorithms. Since the registration step is usually a variational ill-posed model, a mathematical study is needed to check the existence of the solution to the regularized problem. Thus, we prove the existence and uniqueness of the well posed fluid image registration and assure also the existence of the used second order PDE in the restoration step. The results show that the proposed method is competitive with the existing methods.","PeriodicalId":394919,"journal":{"name":"Sci. Ann. Comput. Sci.","volume":"424 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123048822","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}
It is our great pleasure to inform you that SACS has from July 2022 a new editorial team.
我们非常高兴地通知您,从2022年7月起,SACS将有一个新的编辑团队。
{"title":"New Editorial Team for SACS after 16 Years","authors":"Bogdan Aman, Gabriel Ciobanu","doi":"10.7561/SACS.2022.2.181","DOIUrl":"https://doi.org/10.7561/SACS.2022.2.181","url":null,"abstract":"It is our great pleasure to inform you that SACS has from July 2022 a new editorial team.","PeriodicalId":394919,"journal":{"name":"Sci. Ann. Comput. Sci.","volume":"159 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123289743","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}
Four notions of fault are proposed for program specifications each inspired by notions of fault for programs: symptomatic failure resolution fault, Laski fault, MFJ fault and regression test justification of change fault (RTJoC fault). Examples are provided in terms of the PGA style theory of instruction sequences. Each of the notions of fault is based on the contrast between technical specification and requirements specification. The latter contrast is discussed in detail.
{"title":"Four Notions of Fault for Program Specifications","authors":"J. Bergstra","doi":"10.7561/SACS.2022.2.183","DOIUrl":"https://doi.org/10.7561/SACS.2022.2.183","url":null,"abstract":"Four notions of fault are proposed for program specifications each inspired by notions of fault for programs: symptomatic failure resolution fault, Laski fault, MFJ fault and regression test justification of change fault (RTJoC fault). Examples are provided in terms of the PGA style theory of instruction sequences. Each of the notions of fault is based on the contrast between technical specification and requirements specification. The latter contrast is discussed in detail.","PeriodicalId":394919,"journal":{"name":"Sci. Ann. Comput. Sci.","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133509575","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}