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Permeable concrete is an innovative type of concrete that provides a sustainable solution for stormwater management by allowing water to seep through and be filtered naturally. This study focuses on the preparation and performance investigation of an epoxy resin-based permeable concrete containing ceramsite. In this study, ceramsite, a lightweight aggregate, is used as a substitute for conventional aggregates in the concrete mixture. The epoxy resin is then added to improve the strength and durability of the concrete. A series of tests, including compressive strength, water permeability, and freeze-thaw resistance tests, are conducted to evaluate the performance of the epoxy resin-based permeable concrete. The results show that with an increasing epoxy resin binder–aggregate ratio, the compressive strength of the epoxy resin-based permeable concrete significantly increases while the permeability coefficient decreases. Different types of aggregates have varying effects on the compressive strength and permeability coefficient of epoxy resin-based permeable concrete, with high-strength clay ceramsite providing the highest compressive strength and lightweight ceramsite having the highest permeability coefficient. In addition, the discrete element simulation method effectively and feasibly determines the ultimate load and accurately simulates the compressive strength of the permeable cement-based mixture, consistent with the measured compressive strength. A quadratic polynomial regression analysis yielded an R2 value of around 0.93, showing a strong relationship between durability and freeze-thaw cycles. The findings contribute to the development of sustainable construction materials for stormwater management and offer potential applications in various infrastructure projects. [ABSTRACT FROM AUTHOR]

Aims: The primary objective of this study was to determine the prevalence of workplace violence among nurses in China and its association with demographic characteristics, quality of work life and coping styles. The secondary objective was to explore how nurses deal with workplace violence and the emotional/psychological impact of workplace violence on nurses. Background: Workplace violence is a common occupational hazard that causes physical and psychological harm to nurses. Methods: A cross‐sectional study was conducted with 2769 nurses from China. A demographic information questionnaire, hospital workplace violence questionnaire, Chinese version of the work‐related quality of life scale and coping style scale were used in this study. The Chi‐squared test, Mann–Whitney U test and binary logistic regression analysis were used to investigate the effects of demographic characteristics, quality of work life and coping styles on nurses' workplace violence. Results: A total of 49.12% of the nurses (n = 1360) had experienced at least one type of workplace violence in the past 6 months. Night shifts, work department, chronic diseases (odds ratio [OR] = 1.53, p <.001), sleep disorders (OR = 1.54, p <.001), frequent overtime (OR = 1.78, p <.001), adverse nursing events (OR = 2.01, p <.001) and passive coping (OR = 1.47, p <.001) were risk factors for workplace violence. Working conditions (OR = 0.61, p <.001), general well‐being (OR = 0.65, p <.001) and positive coping (OR = 0.76, p <.001) were identified as protective factors for workplace violence. Nurses exposed to workplace violence experience various negative emotional and psychological consequences. Conclusions: Workplace violence is common among nurses in China. Good working conditions, general well‐being and positive coping may help prevent workplace violence injuries. Implications for nursing management: Efforts should be made to improve and optimize existing workplace violence prevention measures, create and maintain a good working environment for health care workers and develop various coping styles or strategies to manage stress to reduce workplace violence. The cross‐sectional study has been approved by the Ethics Committee of the First Affiliated Hospital of China Medical University, with the registration number 2019‐221‐2. Written informed consent was obtained prior to the survey. [ABSTRACT FROM AUTHOR]

Background: The rate of S68G mutation in human immunodeficiency virus type 1 (HIV-1) reverse transcriptase has increased and is closely related to the K65R mutation among CRF01_AE-infected patients who failed treatment. We aimed to explore the temporal association of S68G and K65R mutations and disclose the role of the former on susceptibility to nucleotide/nucleoside reverse transcriptase inhibitor (NRTI) and viral replication with the K65R double mutations among CRF01_AE-infected patients who failed treatment.Methods: The occurrence of S68G and K65R mutations was evaluated among HIV-1 of various subtypes in the global HIV Drug Resistance Database. The temporal association of S68G and K65R mutations was analyzed through next-generation sequencing in four CRF01_AE-infected patients who failed treatment with tenofovir/lamivudine/efavirenz. The impact of the S68G mutation on susceptibility to NRTI and replication fitness was analyzed using pseudovirus phenotypic resistance assays and growth competition assays, respectively.Results: The frequency of the S68G mutation increased by 1.4-9.7% in almost all HIV subtypes and circulating recombinant forms in treatment-experienced patients, except subtype F. The S68G mutation often occurred in conjunction with the K65R mutation among RTI-treated patients, with frequencies ranging 21.1-61.7% in various subtypes. Next-generation sequencing revealed that the S68G mutation occurred following the K65R mutation in three of the four CRF01_AE-infected patients. In these three patients, there was no significant change detected in the half maximal inhibitory concentration for zidovudine, tenofovir, or lamivudine between the K65R and K65R/S68G mutations, as demonstrated by the phenotypic resistance assays. Virus stocks of the K65R and K65R/S68G mutations were mixed with 4:6, 1:1, and 9:1 and cultured for 13 days, the K65R/S68G mutants outgrew those of the K65R mutants irrespective of the input ratio.Conclusions: S68G may be a natural polymorphism and compensatory mutation of K65R selected by NRTIs in the CRF01_AE strain of HIV-1. This mutation does not affect susceptibility to NRTI; however, it improves the replication fitness of K65R mutants. This study deciphers the role of the S68G mutation in the HIV reverse transcriptase of the CRF01_AE strain and provides new evidence for the interpretation of drug-resistant mutations in non-B subtypes of HIV-1. [ABSTRACT FROM AUTHOR]

Abstract In (Aigner, 1988) Aigner conjectured that: 1. K n (n ≥ 3) is 3-optimal only for n = 5 and 8. 2. There are only finitely many 3-optimal graphs K m , n for fixed m. In this paper, the precise result for the complete bipartite graphs K 5 , n is given and the conjecture 2 is proved. [ABSTRACT FROM AUTHOR]

Highlights • A novel approach to search person with free-form natural language is proposed. • The proposed DSFA-Net is an end-to-end Network. • DSFA-Net has a fusion sub-network and an attention sub-network. • Fusion sub-network provides strong initial matching relations. • Attention sub-network enables discriminative words more visually sensitive. Abstract In the task of searching persons from surveillance videos or large scale image dataset, it is more challenging to utilize free-form natural language to retrieve persons than using images and attributes. Thus, to deal with the challenges brought from the complexity of free-from natural language and visual-description mapping, we propose to strengthen the role of textual descriptions by means of fusion and attention mechanisms to make the discriminative words visually sensitive. Specifically, we develop an end-to-end fusion-attention structure, called Description-Strengthened Fusion-Attention Network (DSFA-Net) to tackle the challenging task. Specifically, DSFA-Net has a fusion sub-network and an attention sub-network, where three attention mechanisms are applied. Extensive experiments are performed on the large-scale CUHK-PEDES, which demonstrate the superiority of DSFA-Net. [ABSTRACT FROM AUTHOR]

We study the energy decay for a variable-coefficient wave equation with memory type acoustic boundary conditions. Boundary memory is described by an integral term. Applying the Riemannian geometry method, we obtain the uniform energy decay under some conditions on the memory function and the coefficient matrix. [ABSTRACT FROM AUTHOR]

The study of stabilization and control for PDEs with variable coefficients involves higher level of complexity than the corresponding case of constant coefficients. Further compounding the complexity are the concern and effects of dynamic boundary motion. The problem in its general form is extremely challenging to treat, but under certain specific physical and geometric conditions, such as the time-likeness of the boundary and a limited speed of domain expansion, energy decay estimates can be established and the exact controllability can also be obtained by control-theoretic and Riemannian-geometric methods. Our approach here is based on the Bochner technique of differential geometry in terms of Riemannian metric and geometric multipliers, by generalizing an energy identity method used earlier in Bardos and Chen (1981). Concrete examples are also given to illustrate the geometric conditions and the theorems. [ABSTRACT FROM AUTHOR]

Abstract: Under appropriate assumptions the higher order energy decay rates for the damped wave equations with variable coefficients in are established. The results concern weighted (in time) and pointwise (in time) energy decay estimates. We also obtain weighted estimates for spatial derivatives. [Copyright &y& Elsevier]

An arc in a tournament T with n ≥ 3 vertices is called pancyclic, if it belongs to a cycle of length l for all 3 ≤ l ≤ n. We call a vertex u of T an out-pancyclic vertex of T, if each out-arc of u is pancyclic in T. Yao et al. (Discrete Appl. Math. 99, 245-249, ) proved that every strong tournament contains an out-pancyclic vertex. For strong tournaments with minimum out-degree 1, Yao et al. found an infinite class of strong tournaments, each of which contains exactly one out-pancyclic vertex. In this paper, we prove that every strong tournament with minimum out-degree at least 2 contains three out-pancyclic vertices. Our result is best possible since there is an infinite family of strong tournaments with minimum degree at least 2 and no more than 3 out-pancyclic vertices. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we are concerned with the boundary stabilization of a one-dimensional anti-stable wave equation corrupted by a boundary disturbance. We firstly propose, by weighed moving average technique, a state observer to make an estimation of the disturbance. Secondly, we design a control by the active disturbance rejection strategy to stabilize the system. [Copyright &y& Elsevier]

Abstract: A -hypertournament on vertices, where , is a pair , where is the vertex set of and is a set of -tuples of vertices, called arcs, such that, for all subsets with , contains exactly one permutation of as an arc. Gutin and Yeo (1997) showed in [2] that any strong -hypertournament on vertices, where , is Hamiltonian, and posed the question as to whether the result could be extended to vertex-pancyclicity. As a response, Petrovic and Thomassen (2006) in [4] and Yang (2009) in [6] gave some sufficient conditions for a strong hypertournament to be vertex-pancyclic. In this paper, we prove that, if is a strong -hypertournament on vertices, where , then is vertex-pancyclic. This extends the aforementioned results and Moon’s theorem for tournaments. Furthermore, our result is best possible in the sense that the bound is tight. [Copyright &y& Elsevier]

Abstract: In this work, we are concerned with the boundary stabilization of a one-dimensional wave equation subject to boundary nonlinear uncertainty. The nonlinear uncertainty is first estimated in terms of the output, and then canceled by its estimates. We show that this strategy works well when the derivative of the uncertainty is bounded. [Copyright &y& Elsevier]

Abstract: In this work, two special high-gain tracking differentiators are proposed. By using an ingenious technique which is based on the Taylor expansion, the time lagging phenomenon of the traditional high-gain differentiator is reduced effectively. Therefore, the differentiation exactness of the proposed differentiator is much higher than that of the traditional high-gain tracking differentiator. [Copyright &y& Elsevier]

Yao et al. (Discrete Appl Math 99 (2000), 245-249) proved that every strong tournament contains a vertex u such that every out-arc of u is pancyclic and conjectured that every k-strong tournament contains k such vertices. At present, it is known that this conjecture is true for k = 1, 2, 3 and not true for k⩾4. In this article, we obtain a sufficient and necessary condition for a 4-strong tournament to contain exactly three out-arc pancyclic vertices, which shows that a 4-strong tournament contains at least four out-arc pancyclic vertices except for a given class of tournaments. Furthermore, our proof yields a polynomial algorithm to decide if a 4-strong tournament has exactly three out-arc pancyclic vertices. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we study a nonlinear wave equation with anisotropy and a source term. Under some appropriate assumptions on the parameters, and with certain initial data, we obtain several results on the existence of local solutions and the blow up of solutions in finite time. [Copyright &y& Elsevier]

Abstract: In this paper, we study the following problem with the initial–boundary conditions where is a bounded open interval in , and . We get three sufficient conditions for obtaining the blow-up solutions of the problem. Under some restriction on the parameters in the problem, we conclude that, whether the initial energy is positive or negative, the solution blows up whenever is large enough. [Copyright &y& Elsevier]

Abstract: In this paper, we consider the following problem where is a bounded open interval in , and . We are interested in the interaction between the boundary damping and the interior source . Under some appropriate assumptions on the initial data, two blow-up results with positive initial energy are established. Furthermore, we obtain that the solutions blow up if p or is sufficiently large. [Copyright &y& Elsevier]

Abstract: In this paper, we solve the following combinatorial problem. Let be given sets and be -sets. We lower bound the number of sets such that and, for each , the set does not contain two distinct elements and with , and . Our result directly implies the theorems proved by Bessy et al. [S. Bessy, N. Lichiardopol, J.-S. Sereni, Two proofs of the Bermond–Thomassen conjecture for tournaments with bounded minimum in-degree, Discrete Math. 310 (3) (2010) 557–560]. [Copyright &y& Elsevier]

Abstract: In this paper we consider the wave equation with nonlinear damping and source terms. We are interested in the interaction between the boundary damping and the interior source . We find a sufficient condition for obtaining the blow-up solution of the problem. Furthermore, we also obtain that the solution may blow up even if . [Copyright &y& Elsevier]

Abstract: Volkmann and Winzen [L. Volkmann, S. Winzen, Strong subtournaments containing a given vertex in regular multipartite tournaments, Discrete Math. 308 (2008) 5516–5521] showed that each vertex of a regular -partite tournament with partite sets is contained in a strong subtournament of order for every , and conjectured that each vertex of a regular -partite tournament with partite sets is contained in a strong subtournament of order for every . In this paper we confirm the conjecture when . [Copyright &y& Elsevier]

Abstract: In this paper, we consider a strongly damped wave equation with fractional damping on part of its boundary and also with an internal source. Under some appropriate assumptions on the parameters, and with certain initial data, a blow-up result with positive initial energy is established. [Copyright &y& Elsevier]

Abstract: In this paper, we consider a Cauchy problem for a nonlinear viscoelastic equation with nonlinear damping and source terms. Under suitable assumptions on the initial data and the relaxation function, we establish a finite-time blow-up result and a global existence result. [Copyright &y& Elsevier]

Abstract: We consider the system of nonlinear wave equations with initial and Dirichlet boundary conditions. Under some suitable assumptions on the functions, , , , parameters and the initial data, the result on blow-up of solutions and upper bound of blow-up time are given. [Copyright &y& Elsevier]

Abstract: Volkmann [L. Volkmann, A remark on cycles through an arc in strongly connected multipartite tournaments, Appl. Math. Lett. 20 (2007) 1148–1150] conjectured that a strong -partite tournament with contains three arcs that belong to a cycle of length for each . In this work, we prove that Volkmann’s conjecture is true. [Copyright &y& Elsevier]

Abstract: In this paper, we consider a nonlinear viscoelastic wave equation with nonlinear boundary damping and source terms. Under some appropriate assumptions on the relaxation function and with certain initial data, the global existence of solutions and a general decay for the energy have been established. [Copyright &y& Elsevier]

Abstract: A wave equation with variable coefficients in principal part and memory conditions on the boundary is considered. The Riemannian geometry method is applied to prove the exponential decay of the energy provided the relaxation function also decays exponentially. [Copyright &y& Elsevier]

Abstract: We consider the system of nonlinear wave equations with initial and Dirichlet boundary conditions. Under some suitable assumptions on the functions and , the initial data and the parameters in the equations, the theorems of global existence and nonexistence are proved. [Copyright &y& Elsevier]

Abstract: Yao, Guo and Zhang [T. Yao, Y. Guo, K. Zhang, Pancyclic out-arcs of a vertex in a tournament, Discrete Appl. Math. 99 (2000) 245–249.] proved that every strong tournament contains a vertex such that every out-arc of is pancyclic. In this paper, we prove that every strong tournament with minimum out-degree at least two contains two such vertices. Yeo [A. Yeo, The number of pancyclic arcs in a -strong tournament, J. Graph Theory 50 (2005) 212–219.] conjectured that every 2-strong tournament has three distinct vertices , such that every arc out of and is pancyclic. In this paper, we also prove that Yeo’s conjecture is true. [Copyright &y& Elsevier]

Abstract: An -partite tournament is an orientation of a complete -partite graph. In this paper, we give three supplements to Reid’s theorem [K.B. Reid, Two complementary circuits in two-connected tournaments, Ann. Discrete Math. 27 (1985) 321–334] in multipartite tournaments. The first one is concerned with the lengths of cycles and states as follows: let be an ()-strong -partite tournament with , where is the independence number of , then contains two disjoint cycles of lengths 3 and , respectively, unless is isomorphic to the 7-tournament containing no transitive 4-subtournament (denoted by ). The second one is obtained by considering the number of partite sets that cycles pass through: every ()-strong -partite tournament with contains two disjoint cycles which contain vertices from exactly 3 and partite sets, respectively, unless it is isomorphic to . The last one is about two disjoint cycles passing through all partite sets. [Copyright &y& Elsevier]

Abstract: For a positive integer , a graph is -ordered if for every ordered set of vertices, there is a cycle that encounters the vertices of the set in the given order. If the cycle is also a Hamiltonian cycle, then is said to be -ordered Hamiltonian. We first show that if is a -connected, -ordered graph of order and for every pair of vertices and of with , then is -ordered Hamiltonian unless belongs to an exceptional class of graphs. The latter class is described in this paper. By this result, we prove that is -ordered Hamiltonian if has the order and for every pair of vertices and of with . [Copyright &y& Elsevier]

Abstract: The type of problem under consideration is where is a bounded domain with smooth boundary , . It is proved that if , the positive solution blows up globally in , whereas if , the positive solution is global solution. Furthermore, an upper bound of the “blow-up time”, an upper estimate of the “blow-up rate”, and an upper estimate of the global solutions are given. [Copyright &y& Elsevier]

Abstract: An arc going out from a vertex x in a digraph is called an out-arc of x. Yao et al. [Discrete Appl. Math. 99 (2000) 245–249] proved that every strong tournament contains a vertex x such that all out-arcs of x are pancyclic. Recently, Yeo [J. Graph Theory 50 (2005) 212–219] proved that each 3-strong tournament contains two such vertices. In this paper, we confirm that Yeo''s result is also true for 2-strong tournaments. Our proof implies a polynomial algorithm to find two such vertices. [Copyright &y& Elsevier]

Abstract: Let be a 2-connected simple graph and let denote the distance between two vertices in G. In this paper, it is proved: if the inequality holds for each pair of vertices u and with , then G is Hamiltonian, unless G belongs to an exceptional class of graphs. The latter class is described in this paper. Our result implies the theorem of Ore [Note on Hamilton circuits, Amer. Math. Monthly 67 (1960) 55]. However, it is not included in the theorem of Fan [New sufficient conditions for cycles in graph, J. Combin. Theory Ser. B 37 (1984) 221–227]. [Copyright &y& Elsevier]

Abstract: In this paper, we consider an initial–boundary value problem to a riser vibrating with dissipative term in the equation. It is proved that under suitable conditions that the solution with a negative initial energy blows up in finite time. And we show that the solution with a nonnegative initial energy is global. [Copyright &y& Elsevier]

Abstract: In this paper, we investigate the global solutions and blow-up solutions for a nonlinear string with boundary input and output, and prove that under some conditions, the system has global solutions and blow-up solutions, respectively. [Copyright &y& Elsevier]

Abstract: An arc in a tournament with vertices is called -pancyclic, if it belongs to a cycle of length for all . In this paper, we show that each -strong tournament with contains at least vertices whose out-arcs are 4-pancyclic. [Copyright &y& Elsevier]

Abstract: The type of problem under consideration is where D is a smooth bounded domain of RN . By constructing an auxiliary function and using Hopf''s maximum principles on it, existence theorems of blow-up solutions, upper bound of ‘blow-up time”, upper estimates of “blow-up rate”, existence theorems of global solutions and upper estimates of global solutions are given under suitable assumptions on a, b, f, g, σ, and initial data u 0(x). The obtained results are applied to some examples in which a, b, f, g, and σ are power functions or exponential functions. [Copyright &y& Elsevier]

In this paper, we study the fault-tolerant capability of hypercubes with respect to the hamiltonian property based on the concept of forbidden faulty sets. We show, with the assumption that each vertex is incident with at least three fault-free edges, that an n -dimensional hypercube contains a fault-free hamiltonian cycle, even if there are up to (4 n − 1 3) edge faults. Moreover, we give an example to show that the result is optimal with respect to the number of edge faults tolerated. [ABSTRACT FROM AUTHOR]

The tree connectivity, as a generalization of the traditional connectivity, can serve to measure the capability of connection for vertices in a network. The (n , k) -star graph S n , k can be used to model the topological structure of a large-scale parallel processing system. We show in this article that the 4-set tree connectivity of S n , k is n − 2 , that is, there exist (n − 2) internally disjoint trees connecting x , y , z and w in S n , k for four arbitrary vertices x , y , z and w of S n , k. Two known results about the 3-set tree connectivity of star graphs and (n , k) -star graphs are immediate consequences of our result. [ABSTRACT FROM AUTHOR]

The connectivity is an important measurement for the fault-tolerance of networks. The structure connectivity and substructure connectivity are two generalizations of the classical connectivity. For a fixed graph H , a set F of subgraphs of G is called an H -structure cut (resp., H -substructure cut) of G , if G − ∪ F ∈ F V (F) is disconnected and every element of F is isomorphic to H (resp., a connected subgraph of H). The H -structure connectivity (resp., H -substructure connectivity) of G , denoted by κ (G ; H) (resp., κ s (G ; H)), is the cardinality of a minimal H -structure cut (resp., H -substructure cut) of G. In this paper, we will establish both κ (S n ; H) and κ s (S n , H) for every H ∈ { K 1 , K 1 , 1 , K 1 , 2 , ... , K 1 , n − 2 , P 4 , P 5 , C 6 } , where S n is the n -dimensional star graph. These results will show that star networks are highly tolerant of structure faults. [ABSTRACT FROM AUTHOR]

Compositional data are known as a sort of complex multidimensional data with the feature that reflect the relative information rather than absolute information. There are a variety of models for regression analysis with compositional variables. Similar to the traditional regression analysis, the heteroskedasticity still exists in these models. However, the existing heteroskedastic regression analysis methods cannot apply in these models with compositional error term. In this paper, we mainly study the heteroskedastic linear regression model with compositional response and covariates. The parameter estimator is obtained through weighted least squares method. For the hypothesis test of parameter, the test statistic is based on the original least squares estimator and corresponding heteroskedasticity-consistent covariance matrix estimator. When the proposed method is applied to both simulation and real example, we use the original least squares method as a comparison during the whole process. The results implicate the model's practicality and effectiveness in regression analysis with heteroskedasticity. [ABSTRACT FROM AUTHOR]

The standard regression model designed for real space is not suitable for compositional variables; it should be considered, whether the response and/or covariates are of compositional nature. There are usually three types of multiple regression model with compositional variables: Type 1 refers to the case where all the covariates are compositional data and the response is real; Type 2 is the opposite of Type 1; Type 3 relates to the model with compositional response and covariates. There have been some models for the three types. In this paper, we focus on Type 3 and propose multiple linear regression models including model in the simplex and model in isometric log-ratio (ilr) coordinates. The model in the simplex is based on matrix product, which can project a-part composition to another-part composition, and can deal with different number of parts of compositional variables. Some theorems are given to point out the relationship of parameters between the proposed models. Moreover, the inference for parameters in proposed models is also given. Real example is studied to verify the validity and usefulness of proposed models. [ABSTRACT FROM AUTHOR]

This paper deals with a Cauchy problem for the elasticity system with a structural damping. The decay rates of the total energy of the system are presented by applying the Fourier transform and multiplier in the Fourier space. Furthermore, almost optimal decay estimates of the total energy are obtained based on the Haraux–Komornik inequality. [ABSTRACT FROM AUTHOR]

We study the exact controllability of q uncoupled damped string equations by means of the same control function. This property is called simultaneous controllability. An observability inequality is proved, which implies the simultaneous controllability of the system. Our results generalize the previous results on the linear wave without the dampings. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Let be a hamiltonian undirected graph. A nonempty vertex set is called a hamiltonian cycle enforcing set (in short, an -force set) of if every -cycle of (i.e., a cycle of containing all vertices of ) is hamiltonian. For the graph , is the smallest cardinality of an -force set of and call it the -force number of . In this paper, the definitions of the -force set and the -force number are extended on hypertournaments by using cycles of hypertournaments instead of the cycles of undirected graphs and, the smallest possible -force set of a -hypertournament with vertices is characterized and its -force number is given unless it belongs to the exceptional classes of -hypertournaments. [Copyright &y& Elsevier]

Abstract: Let be a hamiltonian digraph. A nonempty vertex set is called an H-force set of if every -cycle of (i.e. a cycle of containing all vertices of ) is hamiltonian. The H-force number of a digraph is defined to be the smallest cardinality of an -force set of . In this paper, the minimal -force sets of locally semicomplete digraphs are characterized and the -force number is given. [Copyright &y& Elsevier]

Abstract: In this paper, we study the solution to the initial boundary value problem for a class of nonlinear wave equations with damping and source term. By using the energy compensation method, we prove that under some conditions on the initial value, the growth orders of the nonlinear strain term, the damping term, and the source term, the solution to the problem exists globally and blows up respectively, and the estimate for the blow-up time is given. [Copyright &y& Elsevier]

Abstract: In this paper, we study the following reaction diffusion model, where D is a bounded domain in with smooth boundary ∂D, . This paper deals with interactions among three kinds of nonlinear mechanisms: nonlinear reaction, nonlinear convection and nonlinear boundary flux. The existence theorems of blow-up positive solutions, upper bound of “blow-up time,” upper estimates of “blow-up rate,” existence theorems of global positive solutions, and upper estimates of global positive solutions are given under suitable assumptions on and initial data . [Copyright &y& Elsevier]

Pervious concrete has been widely used in parking lots and other lightweight streets. This paper investigates the mechanical strength, porosity and permeability of pervious concrete modified with fly ash, silica fume and basalt fibre. Based on the orthogonal design method, a mixture proportion of pervious concrete was obtained with a compressive strength greater than 40 MPa. In addition, three types of failure mode were observed in 28 d compressive strength tests. The addition of basalt fibre can increase the flexural strength and toughness of pervious concrete. X-ray diffraction and scanning electron microscope tests were conducted to investigate the mineral composition, microstructural evolution and micro-mechanism of strength improvement. The test results indicate that the formation of cementitious compounds can lead to densification of the microstructure of the specimens, which primarily improves the mechanical strength of pervious concrete. This modified pervious concrete with high compressive strength (greater than 40 MPa) and flexural strength (up to 5 MPa) can be applied in most municipal projects. [ABSTRACT FROM AUTHOR]