The hierarchical reconstruction （HR） [Liu, Shu, Tadmor and Zhang, SINUM ＇07] has been successfully applied to prevent oscillations in solutions computed by finite volume, Runge-Kutta discontinuous Galerkin, spectra...The hierarchical reconstruction （HR） [Liu, Shu, Tadmor and Zhang, SINUM ＇07] has been successfully applied to prevent oscillations in solutions computed by finite volume, Runge-Kutta discontinuous Galerkin, spectral volume schemes for solving hyperbolic conservation laws. In this paper, we demonstrate that HR can also be combined with spectral/hp element method for solving hyperbolic conservation laws. An orthogonal spectral basis written in terms of Jacobi polynomials is applied. High computational efficiency is obtained due to such matrix-free algorithm. The formulation is conservative, and essential nomoscillation is enforced by the HR limiter. We show that HR preserves the order of accuracy of the spectral/hp element method for smooth solution problems and generate essentially non-oscillatory solutions profiles for capturing discontinuous solutions without local characteristic decomposition. In addition, we introduce a postprocessing technique to improve HR for limiting high degree numerical solutions.展开更多
AIM:To evaluate whether anterior cruciate ligament(ACL) allograft irradiation is effective for sterility without compromising graft integrity and increasing failure rate.METHODS:A literature search was conducted using...AIM:To evaluate whether anterior cruciate ligament(ACL) allograft irradiation is effective for sterility without compromising graft integrity and increasing failure rate.METHODS:A literature search was conducted using Pub Med,Cochrane,and Google.The following search terms were used:"Gamma irradiation AND anterior cruciate ligament AND allograft" with a return of 30 items.Filters used included:English language,years 1990-2015.There were 6 hits that were not reviewed,as there were only abstracts available.Another 5 hits were discarded,as they did not pertain to the topic of interest.There were 9 more articles that were excluded:Three studies were performed on animals and 6 studies were meta-analyses.Therefore,a total of 10 articles were applicable to review.RESULTS:There is a delicate dosing crossover where gamma irradiation is both effective for sterility without catastrophically compromising the structural integrity of the graft.Of note,low dose irradiation is considered less than 2.0 Mrad,moderate dose is between 2.1-2.4 Mrad,and high dose is greater than or equal to 2.5 Mrad.Based upon the results of the literature search,the optimal threshold for sterilization was found to be sterilization at less than 2.2 Mrad of gamma irradiation with the important caveat of being performed at low temperatures.The graft selection process also must include thorough donor screening and testing as well as harvesting the tissue in a sterile fashion.Utilization of higher dose(≥ 2.5 Mrad) of irradiation causes greater allograft tissue laxity that results in greater graft failure rate clinically in patients after ACL reconstruction.CONCLUSION:Allograft ACL graft gamma irradiatedwith less than 2.2 Mrad appears to be a reasonable alternative to autograft for patients above 25 years of age.展开更多
Since its very release in March 2006, the opinion-soliciting draft of the Labor Contract Law has sparked considerable controversy. Indeed, the whole process of its consideration, promulgation, implementation and amend...Since its very release in March 2006, the opinion-soliciting draft of the Labor Contract Law has sparked considerable controversy. Indeed, the whole process of its consideration, promulgation, implementation and amendment has been accompanied by complex questioning and a diversity of views. This has to some extent reduced appreciation of the value of the Labor Contract Law itself. In the economy and society, rational legal construction can minimize the damage done by the failure of private negotiations. The Labor Contract Law is dedicated to changing the action space of workers and enterprises in order to promote efficiency in production and equity in distribution. With the aim of constructing and developing harmonious and stable labor relations, the law seeks to encourage workers and enterprises to forge communities of shared interests, shared undertakings, a common destiny and a joint mission; it is here that the true value of the law lies. In terms of institutional design, in building a system that categorizes workplace employment, the Labor Contract Law makes a breakthrough in workplace labor relations management and sets up an innovative labor relations management system with Chinese characteristics. Faced with the new normal in labor relations, we should make further progress in strengthening democraticenterprise management, optimizing the developmental environment of business, etc.展开更多
Wagner’s Law can describe the relationship between government expenditures and economic growth.However,its applicability in China remains controversial.In this paper,we first reconstruct two government expenditure in...Wagner’s Law can describe the relationship between government expenditures and economic growth.However,its applicability in China remains controversial.In this paper,we first reconstruct two government expenditure indicators based on the disadvantages of current fiscal expenditure indicators to explain the government scale and then use these indicators to test the applicability of Wagner’s Law in China.Results showed that data from the indicators could support Wagner’s Law well when considering numerical increases in expenditures from 1989 to 2012.However,in terms of relative size of government expenditures proportional increases with the model,the test results of current expenditure indicator do not support the applicability of Wagner’s Law in China.At the same time test results with the two kinds of reconstruction of indicators both can support it well.Overall,the empirical results indicate that new expenditure indicators are more appropriate in testing the applicability of Wagner’s Law in China.展开更多
A natural generalization of random choice finite difference scheme of Harten and Lax for Courant number larger than 1 is obtained. We handle interactions between neighboring Riemann solvers by linear superposition of ...A natural generalization of random choice finite difference scheme of Harten and Lax for Courant number larger than 1 is obtained. We handle interactions between neighboring Riemann solvers by linear superposition of their conserved quantities. We show consistency of the scheme for arbitrarily large Courant numbers. For scalar problems the scheme is total variation diminishing.A brief discussion is given for entropy condition.展开更多
A fourth-order relaxation scheme is derived and applied to hyperbolic systems of conservation laws in one and two space dimensions. The scheme is based on a fourthorder central weighted essentially nonoscillatory （CW...A fourth-order relaxation scheme is derived and applied to hyperbolic systems of conservation laws in one and two space dimensions. The scheme is based on a fourthorder central weighted essentially nonoscillatory （CWENO） reconstruction for one-dimensional cases, which is generalized to two-dimensional cases by the dimension-by-dimension approach. The large stability domain Runge-Kutta-type solver ROCK4 is used for time integration. The resulting method requires neither the use of Riemann solvers nor the computation of Jacobians and therefore it enjoys the main advantage of the relaxation schemes. The high accuracy and high-resolution properties of the present method are demonstrated in one- and two-dimensional numerical experiments.展开更多
For improving global stability of mining environment reconstructing structure,the stress field evolution law of the structure with the filling height change of low-grade backfill was studied by ADINA finite element an...For improving global stability of mining environment reconstructing structure,the stress field evolution law of the structure with the filling height change of low-grade backfill was studied by ADINA finite element analysis code.Three kinds of filling schemes were designed and calculated,in which the filling heights were 2,4,and 7 m,separately.The results show that there are some rules in the stress field with the increase of the filling height as follows:(1) the maximum value of tension stress of the roof decreases gradually,and stress conditions are improved gradually;(2) the tension stress status in the vertical pillar is transformed into the compressive stress status,and the carrying capacity is improved gradually;however,when the filling height is beyond 2.8 m,the carrying capacity of the vertical pillar grows very slowly,so,there is little significance to continue to fill the low-grade backfill;(3) the bottom pillar suffers the squeezing action from the vertical pillars at first and then the gravity action of the low-grade backfill,and the maximum value of tension stress of the bottom pillar firstly increases and then decreases.Considering the economic factor,security and other factors,the low-grade backfill has the most reasonable height(2.8 m) in the scope of all filling height.展开更多
A new class of second order accuracy semidiscrete difference schemes is presented for the two-dimensional nonlinear scalar hyperbolic conservation laws. It is based on flux splitting, piecewise linear cell-averaged re...A new class of second order accuracy semidiscrete difference schemes is presented for the two-dimensional nonlinear scalar hyperbolic conservation laws. It is based on flux splitting, piecewise linear cell-averaged reconstruction and upwind property in the spatial discretization. By using TVD Runge-Kutta time discretization method, the full discrete scheme is obtained and its MmB property is proved. The extension to the two-dimensionalnonlinear hyperbolic conservation law systems is straightforward by using component-wise manner. The main advantage is simple: no Riemann problem is solved, and so field-by-field decomposition is avoided and the complicated computation is reduced. Numerical results of two-dimensional Euler equations of compressible gas dynamics verify the accuracy and robustness of the method.展开更多
基金Research was supported in part by NSF grant DMS-0800612Research was supported by Applied Mathematics program of the US DOE Office of Advanced Scientific Computing ResearchThe Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy under Contract DE-AC05-76RL01830
文摘The hierarchical reconstruction （HR） [Liu, Shu, Tadmor and Zhang, SINUM ＇07] has been successfully applied to prevent oscillations in solutions computed by finite volume, Runge-Kutta discontinuous Galerkin, spectral volume schemes for solving hyperbolic conservation laws. In this paper, we demonstrate that HR can also be combined with spectral/hp element method for solving hyperbolic conservation laws. An orthogonal spectral basis written in terms of Jacobi polynomials is applied. High computational efficiency is obtained due to such matrix-free algorithm. The formulation is conservative, and essential nomoscillation is enforced by the HR limiter. We show that HR preserves the order of accuracy of the spectral/hp element method for smooth solution problems and generate essentially non-oscillatory solutions profiles for capturing discontinuous solutions without local characteristic decomposition. In addition, we introduce a postprocessing technique to improve HR for limiting high degree numerical solutions.
文摘AIM:To evaluate whether anterior cruciate ligament(ACL) allograft irradiation is effective for sterility without compromising graft integrity and increasing failure rate.METHODS:A literature search was conducted using Pub Med,Cochrane,and Google.The following search terms were used:"Gamma irradiation AND anterior cruciate ligament AND allograft" with a return of 30 items.Filters used included:English language,years 1990-2015.There were 6 hits that were not reviewed,as there were only abstracts available.Another 5 hits were discarded,as they did not pertain to the topic of interest.There were 9 more articles that were excluded:Three studies were performed on animals and 6 studies were meta-analyses.Therefore,a total of 10 articles were applicable to review.RESULTS:There is a delicate dosing crossover where gamma irradiation is both effective for sterility without catastrophically compromising the structural integrity of the graft.Of note,low dose irradiation is considered less than 2.0 Mrad,moderate dose is between 2.1-2.4 Mrad,and high dose is greater than or equal to 2.5 Mrad.Based upon the results of the literature search,the optimal threshold for sterilization was found to be sterilization at less than 2.2 Mrad of gamma irradiation with the important caveat of being performed at low temperatures.The graft selection process also must include thorough donor screening and testing as well as harvesting the tissue in a sterile fashion.Utilization of higher dose(≥ 2.5 Mrad) of irradiation causes greater allograft tissue laxity that results in greater graft failure rate clinically in patients after ACL reconstruction.CONCLUSION:Allograft ACL graft gamma irradiatedwith less than 2.2 Mrad appears to be a reasonable alternative to autograft for patients above 25 years of age.
文摘Since its very release in March 2006, the opinion-soliciting draft of the Labor Contract Law has sparked considerable controversy. Indeed, the whole process of its consideration, promulgation, implementation and amendment has been accompanied by complex questioning and a diversity of views. This has to some extent reduced appreciation of the value of the Labor Contract Law itself. In the economy and society, rational legal construction can minimize the damage done by the failure of private negotiations. The Labor Contract Law is dedicated to changing the action space of workers and enterprises in order to promote efficiency in production and equity in distribution. With the aim of constructing and developing harmonious and stable labor relations, the law seeks to encourage workers and enterprises to forge communities of shared interests, shared undertakings, a common destiny and a joint mission; it is here that the true value of the law lies. In terms of institutional design, in building a system that categorizes workplace employment, the Labor Contract Law makes a breakthrough in workplace labor relations management and sets up an innovative labor relations management system with Chinese characteristics. Faced with the new normal in labor relations, we should make further progress in strengthening democraticenterprise management, optimizing the developmental environment of business, etc.
文摘Wagner’s Law can describe the relationship between government expenditures and economic growth.However,its applicability in China remains controversial.In this paper,we first reconstruct two government expenditure indicators based on the disadvantages of current fiscal expenditure indicators to explain the government scale and then use these indicators to test the applicability of Wagner’s Law in China.Results showed that data from the indicators could support Wagner’s Law well when considering numerical increases in expenditures from 1989 to 2012.However,in terms of relative size of government expenditures proportional increases with the model,the test results of current expenditure indicator do not support the applicability of Wagner’s Law in China.At the same time test results with the two kinds of reconstruction of indicators both can support it well.Overall,the empirical results indicate that new expenditure indicators are more appropriate in testing the applicability of Wagner’s Law in China.
基金The Project Supported by National Natural Science Foundation of China.
文摘A natural generalization of random choice finite difference scheme of Harten and Lax for Courant number larger than 1 is obtained. We handle interactions between neighboring Riemann solvers by linear superposition of their conserved quantities. We show consistency of the scheme for arbitrarily large Courant numbers. For scalar problems the scheme is total variation diminishing.A brief discussion is given for entropy condition.
基金the National Natural Science Foundation of China (60134010)The English text was polished by Yunming Chen.
文摘A fourth-order relaxation scheme is derived and applied to hyperbolic systems of conservation laws in one and two space dimensions. The scheme is based on a fourthorder central weighted essentially nonoscillatory （CWENO） reconstruction for one-dimensional cases, which is generalized to two-dimensional cases by the dimension-by-dimension approach. The large stability domain Runge-Kutta-type solver ROCK4 is used for time integration. The resulting method requires neither the use of Riemann solvers nor the computation of Jacobians and therefore it enjoys the main advantage of the relaxation schemes. The high accuracy and high-resolution properties of the present method are demonstrated in one- and two-dimensional numerical experiments.
基金Project(200911MS01) supported by the Scientific Research Fund of Guangxi Provincial Education Department, China Project (XBZ100126) supported by the Scientific Research Foundation of Guangxi University, China Project(2009B005) supported by the Teaching Reform Foundation in the New Century Higher Education of Guangxi Province,China
文摘For improving global stability of mining environment reconstructing structure,the stress field evolution law of the structure with the filling height change of low-grade backfill was studied by ADINA finite element analysis code.Three kinds of filling schemes were designed and calculated,in which the filling heights were 2,4,and 7 m,separately.The results show that there are some rules in the stress field with the increase of the filling height as follows:(1) the maximum value of tension stress of the roof decreases gradually,and stress conditions are improved gradually;(2) the tension stress status in the vertical pillar is transformed into the compressive stress status,and the carrying capacity is improved gradually;however,when the filling height is beyond 2.8 m,the carrying capacity of the vertical pillar grows very slowly,so,there is little significance to continue to fill the low-grade backfill;(3) the bottom pillar suffers the squeezing action from the vertical pillars at first and then the gravity action of the low-grade backfill,and the maximum value of tension stress of the bottom pillar firstly increases and then decreases.Considering the economic factor,security and other factors,the low-grade backfill has the most reasonable height(2.8 m) in the scope of all filling height.
文摘A new class of second order accuracy semidiscrete difference schemes is presented for the two-dimensional nonlinear scalar hyperbolic conservation laws. It is based on flux splitting, piecewise linear cell-averaged reconstruction and upwind property in the spatial discretization. By using TVD Runge-Kutta time discretization method, the full discrete scheme is obtained and its MmB property is proved. The extension to the two-dimensionalnonlinear hyperbolic conservation law systems is straightforward by using component-wise manner. The main advantage is simple: no Riemann problem is solved, and so field-by-field decomposition is avoided and the complicated computation is reduced. Numerical results of two-dimensional Euler equations of compressible gas dynamics verify the accuracy and robustness of the method.
基金the National Natural Science Foundation of China(12071112)and(11471102)the Basic Research Projects for Key Scientific Research Projects in Henan Province(20ZX001)the Research and Practice Project on Education and Teaching Reform in Henan Institute of Science and Technology(2021YB45)。
