AIM: To investigate our clinical experience with combined laparo-endoscopic Rendezvous (RV) for the treatment of patients affected by gallstones and common bile duct (CBD) stones and especially to study the never eval...AIM: To investigate our clinical experience with combined laparo-endoscopic Rendezvous (RV) for the treatment of patients affected by gallstones and common bile duct (CBD) stones and especially to study the never evaluated opinion of the endoscopist concerning the difficulty of the intraoperative endoscopic procedure during the RV in comparison with standard endoscopic retrograde cholangio-pancreatography (ERCP). METHODS: Eighty consecutive patients affected by cholecystolithiasis and diagnosed or suspected CBD stones were treated with a standardized "tailored" RV. The relevant technical features, the feasibility, the effectiveness in stone clearance, the safety but also the simple evaluation of difficulty and agreement of the endoscopist were analyzed with a questionnaire. RESULTS: The feasibility was 97.5% and the effectiveness 100% concerning CBD clearance and solution of coexisting problems at the papilla. Minor morbidity was 3.3%, the operating time was prolonged by a mean of 14 min, the mean hospital stay was 3.8 d and only one stone’s recurrence occurred. The endoscopist evaluated the procedure to be simpler than standard ERCP-ES in 81.2% of the cases.CONCLUSION: Simultaneous RV carries higheffectiveness and safety at least comparable to those reported for other options. The endoscopist is very often satisfied with this approach because of the minimization of some steps of the endoscopic procedure and avoidance of relevant iatrogenic risk factors. If the mandatory collaboration between surgeons and endoscopists is guaranteed, this approach can often be preferable for the patient, the surgeon, the endoscopist and the hospital.展开更多
We construct a class of integrable generalization of Toda mechanics withlong-range interactions. These systems are associated with the loop algebras L(C_r) and L(D_r) inthe sense that their Lax matrices can he realize...We construct a class of integrable generalization of Toda mechanics withlong-range interactions. These systems are associated with the loop algebras L(C_r) and L(D_r) inthe sense that their Lax matrices can he realized in terms of the c = 0 representations of theaffine Lie algebras C_r~((1)) and D_r~((1)) and the interactions pattern involved bears the typicalcharacters of the corresponding root systems. We present the equations of motion and the Hamiltoninnstructure. These generalized systems can be identified unambiguously by specifying the underlyingloop algebra together with an ordered pair of integers (n, m). It turns out that different systemsassociated with the same underlying loop algebra but with different pairs of integers (n_1, m_1) and(n_2, m_2) with n_2 【 n_1 and m_2 【 m_2 can be related by a nested Hamiltonian reduction procedure.For all nontrivial generalizations, the extra coordinates besides the standard Toda variables arePoisson non-commute, and when either n or m ≥ 3, the Poisson structure for the extra coordinatevariables becomes some Lie algebra (i.e. the extra variables appear linearly on the right-hand sideof the Poisson brackets). In the quantum case, such generalizations will become systems withnoncommutative variables without spoiling the integrability.展开更多
In this paper, we study the nonlinear discrete systems and obtain several lyapunov inequalities for them. Then we give the application for lyapunov inequality.
We formulate the subcarrier and power allocation problem in cognitive radio networks employing orthogonal frequency division multiplexing （OFDM） as a non-linear optimization problem with the objective of maximizing ...We formulate the subcarrier and power allocation problem in cognitive radio networks employing orthogonal frequency division multiplexing （OFDM） as a non-linear optimization problem with the objective of maximizing sum capacity under constraints of available subcarriers, interference temperature, power budget, etc. A close-to-optimal solution with much reduced complexity is proposed to separate the problem into two steps, which also considers fairness among secondary users. A fair al- gorithm for subcarrier allocation （FA_SA） is firstly presented. Secondly, a fast iterative water-filling algorithm for power allocation （FIWFA_PA） is also proposed to maximize the sum capacity. Exten- sive simulation results show that sum capacity performance of our low-complexity solution is very close to the optimal one, while significantly improving fairness and reducing computation complexity compared with the existing solutions.展开更多
Under the assumption that in the generalized linear model (GLM) the expectation of the response variable has a correct specification and some other smooth conditions, it is shown that with probability one the quasi-li...Under the assumption that in the generalized linear model (GLM) the expectation of the response variable has a correct specification and some other smooth conditions, it is shown that with probability one the quasi-likelihood equation for the GLM has a solution when the sample size n is sufficiently large. The rate of this solution tending to the true value is determined. In an important special case, this rate is the same as specified in the LIL for iid partial sums and thus cannot be improved anymore.展开更多
Based on the test data of frictional materials and previous research achievements in this field, a generalized non-linear strength theory (GNST) is proposed. It describes non-linear strength properties on the π-plane...Based on the test data of frictional materials and previous research achievements in this field, a generalized non-linear strength theory (GNST) is proposed. It describes non-linear strength properties on the π-plane and the meridian plane using a unified formula, and it includes almost all the present non-linear strength theories, which can be used in just one material. The shape of failure function of the GNST is a smooth curve between the SMP criterion and the Mises criterion on the π-plane, and an exponential curve on the meridian plane. Through the transformed stress space based on the GNST, the combination of the GNST and various constitutive models using p and q as stress parameters can be realized simply and rationally in three-dimensional stress state. Keywords generalized non-linear strength theory (GNST) - transformed stress - constitutive model - application展开更多
This paper proposes a test procedure for testing the regression coefficients in high dimensional partially linear models based on the F-statistic. In the partially linear model, the authors first estimate the unknown ...This paper proposes a test procedure for testing the regression coefficients in high dimensional partially linear models based on the F-statistic. In the partially linear model, the authors first estimate the unknown nonlinear component by some nonparametric methods and then generalize the F-statistic to test the regression coefficients under some regular conditions. During this procedure, the estimation of the nonlinear component brings much challenge to explore the properties of generalized F-test. The authors obtain some asymptotic properties of the generalized F-test in more general cases,including the asymptotic normality and the power of this test with p/n ∈(0, 1) without normality assumption. The asymptotic result is general and by adding some constraint conditions we can obtain the similar conclusions in high dimensional linear models. Through simulation studies, the authors demonstrate good finite-sample performance of the proposed test in comparison with the theoretical results. The practical utility of our method is illustrated by a real data example.展开更多
文摘AIM: To investigate our clinical experience with combined laparo-endoscopic Rendezvous (RV) for the treatment of patients affected by gallstones and common bile duct (CBD) stones and especially to study the never evaluated opinion of the endoscopist concerning the difficulty of the intraoperative endoscopic procedure during the RV in comparison with standard endoscopic retrograde cholangio-pancreatography (ERCP). METHODS: Eighty consecutive patients affected by cholecystolithiasis and diagnosed or suspected CBD stones were treated with a standardized "tailored" RV. The relevant technical features, the feasibility, the effectiveness in stone clearance, the safety but also the simple evaluation of difficulty and agreement of the endoscopist were analyzed with a questionnaire. RESULTS: The feasibility was 97.5% and the effectiveness 100% concerning CBD clearance and solution of coexisting problems at the papilla. Minor morbidity was 3.3%, the operating time was prolonged by a mean of 14 min, the mean hospital stay was 3.8 d and only one stone’s recurrence occurred. The endoscopist evaluated the procedure to be simpler than standard ERCP-ES in 81.2% of the cases.CONCLUSION: Simultaneous RV carries higheffectiveness and safety at least comparable to those reported for other options. The endoscopist is very often satisfied with this approach because of the minimization of some steps of the endoscopic procedure and avoidance of relevant iatrogenic risk factors. If the mandatory collaboration between surgeons and endoscopists is guaranteed, this approach can often be preferable for the patient, the surgeon, the endoscopist and the hospital.
文摘We construct a class of integrable generalization of Toda mechanics withlong-range interactions. These systems are associated with the loop algebras L(C_r) and L(D_r) inthe sense that their Lax matrices can he realized in terms of the c = 0 representations of theaffine Lie algebras C_r~((1)) and D_r~((1)) and the interactions pattern involved bears the typicalcharacters of the corresponding root systems. We present the equations of motion and the Hamiltoninnstructure. These generalized systems can be identified unambiguously by specifying the underlyingloop algebra together with an ordered pair of integers (n, m). It turns out that different systemsassociated with the same underlying loop algebra but with different pairs of integers (n_1, m_1) and(n_2, m_2) with n_2 【 n_1 and m_2 【 m_2 can be related by a nested Hamiltonian reduction procedure.For all nontrivial generalizations, the extra coordinates besides the standard Toda variables arePoisson non-commute, and when either n or m ≥ 3, the Poisson structure for the extra coordinatevariables becomes some Lie algebra (i.e. the extra variables appear linearly on the right-hand sideof the Poisson brackets). In the quantum case, such generalizations will become systems withnoncommutative variables without spoiling the integrability.
基金Supported by NSF of Zhejiang Province(2006A05192)
文摘In this paper, we study the nonlinear discrete systems and obtain several lyapunov inequalities for them. Then we give the application for lyapunov inequality.
基金Supported by the National High Technology Research and Development Programme of China（ No. 2007AA01Z221, No. 2009AA01Z246） , and the National Natural Science Foundation of China（ No. 60672124, 60832009）.
文摘We formulate the subcarrier and power allocation problem in cognitive radio networks employing orthogonal frequency division multiplexing （OFDM） as a non-linear optimization problem with the objective of maximizing sum capacity under constraints of available subcarriers, interference temperature, power budget, etc. A close-to-optimal solution with much reduced complexity is proposed to separate the problem into two steps, which also considers fairness among secondary users. A fair al- gorithm for subcarrier allocation （FA_SA） is firstly presented. Secondly, a fast iterative water-filling algorithm for power allocation （FIWFA_PA） is also proposed to maximize the sum capacity. Exten- sive simulation results show that sum capacity performance of our low-complexity solution is very close to the optimal one, while significantly improving fairness and reducing computation complexity compared with the existing solutions.
基金This work was supported by the National Natural Science Foundation of China.
文摘Under the assumption that in the generalized linear model (GLM) the expectation of the response variable has a correct specification and some other smooth conditions, it is shown that with probability one the quasi-likelihood equation for the GLM has a solution when the sample size n is sufficiently large. The rate of this solution tending to the true value is determined. In an important special case, this rate is the same as specified in the LIL for iid partial sums and thus cannot be improved anymore.
基金the National Natural Science Foundation of China ( Grant No. 10272010) the Ministry of Science and Technology of China (Grant No. 2002CCC00200).
文摘Based on the test data of frictional materials and previous research achievements in this field, a generalized non-linear strength theory (GNST) is proposed. It describes non-linear strength properties on the π-plane and the meridian plane using a unified formula, and it includes almost all the present non-linear strength theories, which can be used in just one material. The shape of failure function of the GNST is a smooth curve between the SMP criterion and the Mises criterion on the π-plane, and an exponential curve on the meridian plane. Through the transformed stress space based on the GNST, the combination of the GNST and various constitutive models using p and q as stress parameters can be realized simply and rationally in three-dimensional stress state. Keywords generalized non-linear strength theory (GNST) - transformed stress - constitutive model - application
基金supported by the Natural Science Foundation of China under Grant Nos.11231010,11471223,11501586BCMIIS and Key Project of Beijing Municipal Educational Commission under Grant No.KZ201410028030
文摘This paper proposes a test procedure for testing the regression coefficients in high dimensional partially linear models based on the F-statistic. In the partially linear model, the authors first estimate the unknown nonlinear component by some nonparametric methods and then generalize the F-statistic to test the regression coefficients under some regular conditions. During this procedure, the estimation of the nonlinear component brings much challenge to explore the properties of generalized F-test. The authors obtain some asymptotic properties of the generalized F-test in more general cases,including the asymptotic normality and the power of this test with p/n ∈(0, 1) without normality assumption. The asymptotic result is general and by adding some constraint conditions we can obtain the similar conclusions in high dimensional linear models. Through simulation studies, the authors demonstrate good finite-sample performance of the proposed test in comparison with the theoretical results. The practical utility of our method is illustrated by a real data example.
