In this paper, we provide some new necessary and sufficient conditions for generalized diagonally dominant matrices and also obtain some criteria for nongeneralized dominant matrices.
The parameters that influence slope stability and their criteria of failure are fairly understood but over-conservative design approaches are often preferred,which can result in excessive overburden removal that may j...The parameters that influence slope stability and their criteria of failure are fairly understood but over-conservative design approaches are often preferred,which can result in excessive overburden removal that may jeopardize profitability in the context of open pit mining.Numerical methods such as finite element and discrete element modelling are instrumental to identify specific zones of stability,but they remain approximate and do not pinpoint the critical factors that influence stability without extensive parametric studies.A large number of degrees of freedom and input parameters may make the outcome of numerical modelling insufficient compared to analytical solutions.Existing analytical approaches have not tackled the stability of slopes using non-linear plasticity criteria and threedimensional failure mechanisms.This paper bridges this gap by using the yield design theory and the Hoek-Brown criterion.Moreover,the proposed model includes the effect of seismic forces,which are not always taken into account in slope stability analyses.The results are presented in the form of rigorous mathematical expressions and stability charts involving the loading conditions and the rock mass properties emanating from the plasticity criterion.展开更多
Generalized strictly diagonally dominant matrices play a wide and important role in computational mathematics, mathematical physics, theory of dynamical systems, etc.But it is difficult to judge a matrix is or not gen...Generalized strictly diagonally dominant matrices play a wide and important role in computational mathematics, mathematical physics, theory of dynamical systems, etc.But it is difficult to judge a matrix is or not generalized strictly diagonally dominant matrix.In this paper, by using the properties of α-chain diagonally dominant matrix, we obtain new criteria for judging generalized strictly diagonally dominant matrix, which enlarge the identification range.展开更多
In this paper, we provide some new criteria conditions for generalized strictly diagonally dominant matrices, such that the corresponding results in [1] are generalized and improved.
Background: Patients with generalized anxiety disorder (GAD) are among the highest users of healthcare resources. The broadening of the DSM-IV criteria for GAD has been a subject of controversy in the literature, but ...Background: Patients with generalized anxiety disorder (GAD) are among the highest users of healthcare resources. The broadening of the DSM-IV criteria for GAD has been a subject of controversy in the literature, but its consequences have not been analyzed to date. Objective: The purpose of this study was to analyze how the broadening of the DSM-IV criteria affects healthcare resource utilization and related costs. Methods: A multicentre, prospective, observational study was conducted in randomly selected outpatient psychiatric clinics between October 2007 and April 2008. Patients diagnosed according to DSM-IV or broader criteria (1 month of excessive or non-excessive worry and only 2 associated DSM-IV symptoms) for the first time were consecutively enrolled. Socio-demographic data, healthcare resources and corresponding costs were collected over a 6-month period. Results: A total of 3549 patients were systematically recruited, 1815 in the DSM-IV criteria group (DG) and1264 inthe broad criteria group (BG). Treatments prescribed were similar for antidepressants in both groups (77.0% in the DG vs. 75.3% in the BG, p = 0.284), and slightly higher in the DG for benzodiazepines (71.5% vs. 67.2% respectively, p = 0.011) and anticonvulsants (72.1% vs. 67.0% respectively, p = 0.002). Healthcare resource utilization was statistically reduced to a similar extent in both groups as a consequence of treatment, yielding a reduction in the cost of illness of €1196 (SD = 1158) and €1112 (SD = 874) respectively;p = 0.304, over a 6-month period. Conclusion: The broadening of the GAD criteria could lead to earlier diagnosis not necessarily associated with an increase in healthcare resource utilization or costs to the National Health System in the six-month follow-up.展开更多
Currently, second generation intact stability criteria are being developed and evaluated by the International Maritime Organization(IMO). In this paper, we briefly present levels 1 and 2 assessment methods for the cri...Currently, second generation intact stability criteria are being developed and evaluated by the International Maritime Organization(IMO). In this paper, we briefly present levels 1 and 2 assessment methods for the criteria of pure loss of stability and parametric roll failure modes. Subsequently, we show the KG_(max) curves associated with these criteria. We compute these curves for five different types of ships and compare them with the curves embodied in the current regulations. The results show that the safety margin ensured by the first level-1 method of calculation for both pure loss of stability and parametric roll seems to be excessive in many cases. They also show that the KG_(max) given by the second level-1 method and by the level-2 method may be very similar. In some cases, the level-2 method can be more conservative than the second level-1 method, which is unanticipated by the future regulation. The KG_(max) curves associated with parametric roll confirm that the C11 container ship is vulnerable to this failure mode. The computation of the second check coefficient of parametric roll level 2(C2) for all possible values of KG reveals the existence of both authorized and restricted areas on the surface formed by both the draft and KG, which may replace the classical KG_(max) curves. In consequence, it is not sufficient to check that C2 is lower than the maximum authorized value(R_(PR0)) for a fixed ship's loading condition.展开更多
By employing a generalized Riccati technique and an integral averaging tech-nique, new interval oscillation criteria are established for the forced second-order half-lineardifferential equation [r(t)|x′ (t)|α-1x′ (...By employing a generalized Riccati technique and an integral averaging tech-nique, new interval oscillation criteria are established for the forced second-order half-lineardifferential equation [r(t)|x′ (t)|α-1x′ (t)]′ + q(t)|x(t)|α-1x(t) = e(t).展开更多
In the article, the methods of investigating the instability that were formulated earlier by the authors are systematized in the form of a set of criteria for the instability and chaos. The latest ones are used to stu...In the article, the methods of investigating the instability that were formulated earlier by the authors are systematized in the form of a set of criteria for the instability and chaos. The latest ones are used to study chaotic dynamics in the problems of Sprott and the nonlinear electronic generator of the CRC.展开更多
This paper discusses a class of forced second-order half-linear differential equations. By using the generalized Riccati technique and the averaging technique, some new interval oscillation criteria are obtained.
In this paper,we consider a class of third-order nonlinear delay dynamic equations.First,we establish a Kiguradze-type lemma and some useful estimates.Second,we give a sufficient and necessary condition for the existe...In this paper,we consider a class of third-order nonlinear delay dynamic equations.First,we establish a Kiguradze-type lemma and some useful estimates.Second,we give a sufficient and necessary condition for the existence of eventually positive solutions having upper bounds and tending to zero.Third,we obtain new oscillation criteria by employing the Potzsche chain rule.Then,using the generalized Riccati transformation technique and averaging method,we establish the Philos-type oscillation criteria.Surprisingly,the integral value of the Philos-type oscillation criteria,which guarantees that all unbounded solutions oscillate,is greater than θ_(4)(t_(1),T).The results of Theorem 3.5 and Remark 3.6 are novel.Finally,we offer four examples to illustrate our results.展开更多
Let X, Y be Banach spaces and M be a linear subspace in X x Y = {{x,y}lx E X,y C Y}. We may view M as a multi-valued linear operator from X to Y by taking M（x） = {yl（x,y} C M}. In this paper, we give several criter...Let X, Y be Banach spaces and M be a linear subspace in X x Y = {{x,y}lx E X,y C Y}. We may view M as a multi-valued linear operator from X to Y by taking M（x） = {yl（x,y} C M}. In this paper, we give several criteria for a single-valued operator from Y to X to be the metric generalized inverse of the multi-valued linear operator M. The principal tool in this paper is also the generalized orthogonal decomposition theorem in Banach spaces.展开更多
文摘In this paper, we provide some new necessary and sufficient conditions for generalized diagonally dominant matrices and also obtain some criteria for nongeneralized dominant matrices.
文摘The parameters that influence slope stability and their criteria of failure are fairly understood but over-conservative design approaches are often preferred,which can result in excessive overburden removal that may jeopardize profitability in the context of open pit mining.Numerical methods such as finite element and discrete element modelling are instrumental to identify specific zones of stability,but they remain approximate and do not pinpoint the critical factors that influence stability without extensive parametric studies.A large number of degrees of freedom and input parameters may make the outcome of numerical modelling insufficient compared to analytical solutions.Existing analytical approaches have not tackled the stability of slopes using non-linear plasticity criteria and threedimensional failure mechanisms.This paper bridges this gap by using the yield design theory and the Hoek-Brown criterion.Moreover,the proposed model includes the effect of seismic forces,which are not always taken into account in slope stability analyses.The results are presented in the form of rigorous mathematical expressions and stability charts involving the loading conditions and the rock mass properties emanating from the plasticity criterion.
基金Supported by the National Natural Science Foundation of China（71261010）
文摘Generalized strictly diagonally dominant matrices play a wide and important role in computational mathematics, mathematical physics, theory of dynamical systems, etc.But it is difficult to judge a matrix is or not generalized strictly diagonally dominant matrix.In this paper, by using the properties of α-chain diagonally dominant matrix, we obtain new criteria for judging generalized strictly diagonally dominant matrix, which enlarge the identification range.
基金Supported by the Nature Science Foundation of Henan Province（2003110010）
文摘In this paper, we provide some new criteria conditions for generalized strictly diagonally dominant matrices, such that the corresponding results in [1] are generalized and improved.
文摘Background: Patients with generalized anxiety disorder (GAD) are among the highest users of healthcare resources. The broadening of the DSM-IV criteria for GAD has been a subject of controversy in the literature, but its consequences have not been analyzed to date. Objective: The purpose of this study was to analyze how the broadening of the DSM-IV criteria affects healthcare resource utilization and related costs. Methods: A multicentre, prospective, observational study was conducted in randomly selected outpatient psychiatric clinics between October 2007 and April 2008. Patients diagnosed according to DSM-IV or broader criteria (1 month of excessive or non-excessive worry and only 2 associated DSM-IV symptoms) for the first time were consecutively enrolled. Socio-demographic data, healthcare resources and corresponding costs were collected over a 6-month period. Results: A total of 3549 patients were systematically recruited, 1815 in the DSM-IV criteria group (DG) and1264 inthe broad criteria group (BG). Treatments prescribed were similar for antidepressants in both groups (77.0% in the DG vs. 75.3% in the BG, p = 0.284), and slightly higher in the DG for benzodiazepines (71.5% vs. 67.2% respectively, p = 0.011) and anticonvulsants (72.1% vs. 67.0% respectively, p = 0.002). Healthcare resource utilization was statistically reduced to a similar extent in both groups as a consequence of treatment, yielding a reduction in the cost of illness of €1196 (SD = 1158) and €1112 (SD = 874) respectively;p = 0.304, over a 6-month period. Conclusion: The broadening of the GAD criteria could lead to earlier diagnosis not necessarily associated with an increase in healthcare resource utilization or costs to the National Health System in the six-month follow-up.
文摘Currently, second generation intact stability criteria are being developed and evaluated by the International Maritime Organization(IMO). In this paper, we briefly present levels 1 and 2 assessment methods for the criteria of pure loss of stability and parametric roll failure modes. Subsequently, we show the KG_(max) curves associated with these criteria. We compute these curves for five different types of ships and compare them with the curves embodied in the current regulations. The results show that the safety margin ensured by the first level-1 method of calculation for both pure loss of stability and parametric roll seems to be excessive in many cases. They also show that the KG_(max) given by the second level-1 method and by the level-2 method may be very similar. In some cases, the level-2 method can be more conservative than the second level-1 method, which is unanticipated by the future regulation. The KG_(max) curves associated with parametric roll confirm that the C11 container ship is vulnerable to this failure mode. The computation of the second check coefficient of parametric roll level 2(C2) for all possible values of KG reveals the existence of both authorized and restricted areas on the surface formed by both the draft and KG, which may replace the classical KG_(max) curves. In consequence, it is not sufficient to check that C2 is lower than the maximum authorized value(R_(PR0)) for a fixed ship's loading condition.
文摘By employing a generalized Riccati technique and an integral averaging tech-nique, new interval oscillation criteria are established for the forced second-order half-lineardifferential equation [r(t)|x′ (t)|α-1x′ (t)]′ + q(t)|x(t)|α-1x(t) = e(t).
文摘In the article, the methods of investigating the instability that were formulated earlier by the authors are systematized in the form of a set of criteria for the instability and chaos. The latest ones are used to study chaotic dynamics in the problems of Sprott and the nonlinear electronic generator of the CRC.
文摘This paper discusses a class of forced second-order half-linear differential equations. By using the generalized Riccati technique and the averaging technique, some new interval oscillation criteria are obtained.
基金supported by the National Natural Science Foundation of China(12071491,12001113)。
文摘In this paper,we consider a class of third-order nonlinear delay dynamic equations.First,we establish a Kiguradze-type lemma and some useful estimates.Second,we give a sufficient and necessary condition for the existence of eventually positive solutions having upper bounds and tending to zero.Third,we obtain new oscillation criteria by employing the Potzsche chain rule.Then,using the generalized Riccati transformation technique and averaging method,we establish the Philos-type oscillation criteria.Surprisingly,the integral value of the Philos-type oscillation criteria,which guarantees that all unbounded solutions oscillate,is greater than θ_(4)(t_(1),T).The results of Theorem 3.5 and Remark 3.6 are novel.Finally,we offer four examples to illustrate our results.
基金Supported by National Natural Science Foundation of China (Grant No. 11071051)
文摘Let X, Y be Banach spaces and M be a linear subspace in X x Y = {{x,y}lx E X,y C Y}. We may view M as a multi-valued linear operator from X to Y by taking M（x） = {yl（x,y} C M}. In this paper, we give several criteria for a single-valued operator from Y to X to be the metric generalized inverse of the multi-valued linear operator M. The principal tool in this paper is also the generalized orthogonal decomposition theorem in Banach spaces.
