The thrust and the torque of various carbide drills are studied for the high-speed drilling of fiber reinforced epoxy composites. The orthogonal experiment is carried out with different feed speeds at high rotation sp...The thrust and the torque of various carbide drills are studied for the high-speed drilling of fiber reinforced epoxy composites. The orthogonal experiment is carried out with different feed speeds at high rotation speed. Experimental results show that the spindle rotation speed is the most influential factor. The thrust andthe torque decrease under the condition of high rotation rate. With the decrease of the feed speed, the thrust and the torque decrease. But the effect of the feed speed is less than that of the spindle rotation rate. Moreover, the effect of drill materials on the thrust and the torque is more notable than that of the drill geometries and the feed speed. The thrust is greatly affected by the feed speed while the torque is obviously affected by drill geometries.展开更多
Orthomorphism on F2^n is a kind of elementary pemmtation with good cryptographic properties. This paper proposes a hybrid strategy of Particle Swarm Optimization （PSO） and Sirrmlated Annealing （SA） for finding ort...Orthomorphism on F2^n is a kind of elementary pemmtation with good cryptographic properties. This paper proposes a hybrid strategy of Particle Swarm Optimization （PSO） and Sirrmlated Annealing （SA） for finding orthomorphisrm with good cryptographic properties. By experiment based on this strategy, we get some orthorrorphisrm on F2^n = 5, 6, 7, 9, 10） with good cryptographic properties in the open document for the first time, and the optirml orthorrrphism on F found in this paper also does better than the one proposed by Feng Dengguo et al. in stream cipher Loiss in difference uniformity, algebraic degree, algebraic irrarnity and corresponding pernmtation polynomial degree. The PSOSA hybrid strategy for optimizing orthomerphism in this paper makes design of orthorrorphisrm with good cryptographic properties automated, efficient and convenient, which proposes a new approach to design orthornorphisrm.展开更多
Some problems connect ed with production of new light-weight filler type are considered for sandwich layers. Constructively, the filler is the folded structure that can be developed on a plane. This feature makes it...Some problems connect ed with production of new light-weight filler type are considered for sandwich layers. Constructively, the filler is the folded structure that can be developed on a plane. This feature makes it possible to produce the filler by isometric t ransformation of thin sheet through local bending without material stretching.Th e main difficulty is that the bending must be carried out along all lines of com plex-shaped marking-out at a time. The problem of shaping can be solved by use of the original shaping device that can be transformed in operation. The herein -presented technology of production makes it possible to fabricate parts with d eep relief using a wide gamut of different materials even as the thin-sheet met al alloys and paper.展开更多
In this paper, let T be a bounded linear operator on a complex Hilbert H. We give and prove that every p-w-hyponormal operator has Bishop's property(β) and spectral properties; Quasi-similar p-w-hyponormal operat...In this paper, let T be a bounded linear operator on a complex Hilbert H. We give and prove that every p-w-hyponormal operator has Bishop's property(β) and spectral properties; Quasi-similar p-w-hyponormal operators have equal spectra and equal essential spectra. Finally, for p-w-hyponormal operators, we give a kind of proof of its normality by use of properties of partial isometry.展开更多
Objective:To investigate the effect and mechanism of nordihydroguaiaretic acid (NDGA) on apoptosis in human malignant glioma cell line SHG-44. Methods: Cell growth inhibition was measured with MTT assay. Cell apoptosi...Objective:To investigate the effect and mechanism of nordihydroguaiaretic acid (NDGA) on apoptosis in human malignant glioma cell line SHG-44. Methods: Cell growth inhibition was measured with MTT assay. Cell apoptosis was observed with light and electron microscopy and TUNEL. Expression of bcl-2 gene was measured with immunohistochemistry, in situ hybridization and image analyses. Results: NDGA at the concentration of 100 μmol/L inhibited the proliferation of SHG-44 cells and induced apoptosis in a time-dependent manner. The expression of Bcl-2 protein in SHG-44 cells was decreased in the present of 100 μmol/L NDGA along with the duration of treatment in a negative correlation with the degree of cell apoptosis. The bcl-2 mRNA expressed in SHG-44 cells was reduced after treatment with 100 μmol/L NDGA, apparently consistent with the immunohistochemical results. Conclusion: NDGA can induce apoptosis of human malignant glioma cells probably by down-regulating expression of bcl-2 gene, though the exact mechanism needs further study.展开更多
Objective To investigate the mutations of mitochondrial genome in a pedigree with suspected maternally inherited diabetes and deafness and to explore the correlations between the mutations and clinical features. Meth...Objective To investigate the mutations of mitochondrial genome in a pedigree with suspected maternally inherited diabetes and deafness and to explore the correlations between the mutations and clinical features. Methods Genomic DNA was isolated from blood leucocytes of each member of the pedigree. The mitochondrial genome was amplified with 24-pair primers that could cover the entire mitochondrial DNA. Direct sequencing of PCR products was used to identify any mitochondrial DNA mutations. Results Family members on the maternal side all harbored the tRNA^Lcu（UUR） A3243G mutation. The paternal side family members did not have the mutation. The age-of-onset of diabetes of the 4 maternal side family members was 15, 41, 44, and 65 years old, and their corresponding heteroplasmy level of the mutation was 34.5%, 14.9%, 14.6%, and 5.9%, respectively. The age-of-onset of diabetes and heteroplasmy level of A3243G mutation were negatively correlated with a correlation coefficient of -0.980（P=0.02）. Meanwhile, patient with high heteroplasmy level of A3243G mutation had relatively low severity of disease. Moreover, 6 reported polymorphisms and 2 new variants were found. Conclusions The main cause of diabetes in this pedigree is the tRNA^Lcu（UUR） A3243G mutation. However, other gene variants may contribute to its pathogenicity. The heteroplasmy level of the tRNA^Lcu（UUR） A3243G mutation is positively associated with earlier age-of-onset and increasing severity of diabetes.展开更多
In this paper two sequences of generalized Landau linear positive operators are introduced. They can be applied in approximating continuous functions with arbitrary growth order, defined on a finite interval or the wh...In this paper two sequences of generalized Landau linear positive operators are introduced. They can be applied in approximating continuous functions with arbitrary growth order, defined on a finite interval or the whole real axis. The properties of approximation are studied and their asymptotic formulae are presented. These results show that their degrees of approximation are the best among existing operator sequences of Landau type, for example, their degrees of approximation for C 2[0, 1] are O(1/n 2) but corresponding degree of ordinary Landau operators are only O(1/n).展开更多
In the process of accurate interpretation of multi-wave seismic data,we wanted to solve the problem of multi-wave information recognition.Based on techniques of elastic wave forwarding,targeting the geological model o...In the process of accurate interpretation of multi-wave seismic data,we wanted to solve the problem of multi-wave information recognition.Based on techniques of elastic wave forwarding,targeting the geological model of a reservoir of an oil field exploration area,we used a high-order staggered-grid difference technology to simulate many shots of seismic records of nonzero offset shots,implemented multi-wave seismic data processing to acquire the CMP of P waves and converted waves,NMO traces of CCP pre stacks,including AVA information and superposition profiles.Based on the AVA calculation of the model,the layer parameters of the model and the forwarding wave field relations of the P-S wave,we also compared and studied the correspondence between P waves and converted waves.The results of our analysis show that the results from simulation and from the AVO analysis are consistent.Significant wave field differences between P waves and converted waves in the same reservoir were found,which are helpful in recognizing and interpreting the multi-wave information in this area.We made use of the multi-wave data to provide the important guidelines for reservoir prediction.展开更多
文摘The thrust and the torque of various carbide drills are studied for the high-speed drilling of fiber reinforced epoxy composites. The orthogonal experiment is carried out with different feed speeds at high rotation speed. Experimental results show that the spindle rotation speed is the most influential factor. The thrust andthe torque decrease under the condition of high rotation rate. With the decrease of the feed speed, the thrust and the torque decrease. But the effect of the feed speed is less than that of the spindle rotation rate. Moreover, the effect of drill materials on the thrust and the torque is more notable than that of the drill geometries and the feed speed. The thrust is greatly affected by the feed speed while the torque is obviously affected by drill geometries.
基金supported by the National Natural Science Foundation of China under Grants No.60673071,No.60970115,No.60970116,No.61003267partially supported by the National Hi-Tech Research and Department Program of China under Grants No.2006AA01Z442,No.2007AA01Z411
文摘Orthomorphism on F2^n is a kind of elementary pemmtation with good cryptographic properties. This paper proposes a hybrid strategy of Particle Swarm Optimization （PSO） and Sirrmlated Annealing （SA） for finding orthomorphisrm with good cryptographic properties. By experiment based on this strategy, we get some orthorrorphisrm on F2^n = 5, 6, 7, 9, 10） with good cryptographic properties in the open document for the first time, and the optirml orthorrrphism on F found in this paper also does better than the one proposed by Feng Dengguo et al. in stream cipher Loiss in difference uniformity, algebraic degree, algebraic irrarnity and corresponding pernmtation polynomial degree. The PSOSA hybrid strategy for optimizing orthomerphism in this paper makes design of orthorrorphisrm with good cryptographic properties automated, efficient and convenient, which proposes a new approach to design orthornorphisrm.
文摘Some problems connect ed with production of new light-weight filler type are considered for sandwich layers. Constructively, the filler is the folded structure that can be developed on a plane. This feature makes it possible to produce the filler by isometric t ransformation of thin sheet through local bending without material stretching.Th e main difficulty is that the bending must be carried out along all lines of com plex-shaped marking-out at a time. The problem of shaping can be solved by use of the original shaping device that can be transformed in operation. The herein -presented technology of production makes it possible to fabricate parts with d eep relief using a wide gamut of different materials even as the thin-sheet met al alloys and paper.
基金Natural Science and Education Foundation of Henan Province(2007110016)
文摘In this paper, let T be a bounded linear operator on a complex Hilbert H. We give and prove that every p-w-hyponormal operator has Bishop's property(β) and spectral properties; Quasi-similar p-w-hyponormal operators have equal spectra and equal essential spectra. Finally, for p-w-hyponormal operators, we give a kind of proof of its normality by use of properties of partial isometry.
基金National Natural Science Foundation of China (No. 39670296)
文摘Objective:To investigate the effect and mechanism of nordihydroguaiaretic acid (NDGA) on apoptosis in human malignant glioma cell line SHG-44. Methods: Cell growth inhibition was measured with MTT assay. Cell apoptosis was observed with light and electron microscopy and TUNEL. Expression of bcl-2 gene was measured with immunohistochemistry, in situ hybridization and image analyses. Results: NDGA at the concentration of 100 μmol/L inhibited the proliferation of SHG-44 cells and induced apoptosis in a time-dependent manner. The expression of Bcl-2 protein in SHG-44 cells was decreased in the present of 100 μmol/L NDGA along with the duration of treatment in a negative correlation with the degree of cell apoptosis. The bcl-2 mRNA expressed in SHG-44 cells was reduced after treatment with 100 μmol/L NDGA, apparently consistent with the immunohistochemical results. Conclusion: NDGA can induce apoptosis of human malignant glioma cells probably by down-regulating expression of bcl-2 gene, though the exact mechanism needs further study.
文摘Objective To investigate the mutations of mitochondrial genome in a pedigree with suspected maternally inherited diabetes and deafness and to explore the correlations between the mutations and clinical features. Methods Genomic DNA was isolated from blood leucocytes of each member of the pedigree. The mitochondrial genome was amplified with 24-pair primers that could cover the entire mitochondrial DNA. Direct sequencing of PCR products was used to identify any mitochondrial DNA mutations. Results Family members on the maternal side all harbored the tRNA^Lcu（UUR） A3243G mutation. The paternal side family members did not have the mutation. The age-of-onset of diabetes of the 4 maternal side family members was 15, 41, 44, and 65 years old, and their corresponding heteroplasmy level of the mutation was 34.5%, 14.9%, 14.6%, and 5.9%, respectively. The age-of-onset of diabetes and heteroplasmy level of A3243G mutation were negatively correlated with a correlation coefficient of -0.980（P=0.02）. Meanwhile, patient with high heteroplasmy level of A3243G mutation had relatively low severity of disease. Moreover, 6 reported polymorphisms and 2 new variants were found. Conclusions The main cause of diabetes in this pedigree is the tRNA^Lcu（UUR） A3243G mutation. However, other gene variants may contribute to its pathogenicity. The heteroplasmy level of the tRNA^Lcu（UUR） A3243G mutation is positively associated with earlier age-of-onset and increasing severity of diabetes.
文摘In this paper two sequences of generalized Landau linear positive operators are introduced. They can be applied in approximating continuous functions with arbitrary growth order, defined on a finite interval or the whole real axis. The properties of approximation are studied and their asymptotic formulae are presented. These results show that their degrees of approximation are the best among existing operator sequences of Landau type, for example, their degrees of approximation for C 2[0, 1] are O(1/n 2) but corresponding degree of ordinary Landau operators are only O(1/n).
基金the Doctor Research Fund for Universities of China (No.20070616004)the National High Technology Research and Development Program of China (No.2007AA060505)
文摘In the process of accurate interpretation of multi-wave seismic data,we wanted to solve the problem of multi-wave information recognition.Based on techniques of elastic wave forwarding,targeting the geological model of a reservoir of an oil field exploration area,we used a high-order staggered-grid difference technology to simulate many shots of seismic records of nonzero offset shots,implemented multi-wave seismic data processing to acquire the CMP of P waves and converted waves,NMO traces of CCP pre stacks,including AVA information and superposition profiles.Based on the AVA calculation of the model,the layer parameters of the model and the forwarding wave field relations of the P-S wave,we also compared and studied the correspondence between P waves and converted waves.The results of our analysis show that the results from simulation and from the AVO analysis are consistent.Significant wave field differences between P waves and converted waves in the same reservoir were found,which are helpful in recognizing and interpreting the multi-wave information in this area.We made use of the multi-wave data to provide the important guidelines for reservoir prediction.
