AIM: TO re-evaluate the recent clinicopathological fea- tures of remnant gastric cancer (RGC) and to develop desirable surveillance programs.METHODS: Between 1997 and 2008, 1149 patients underwent gastrectomy for ...AIM: TO re-evaluate the recent clinicopathological fea- tures of remnant gastric cancer (RGC) and to develop desirable surveillance programs.METHODS: Between 1997 and 2008, 1149 patients underwent gastrectomy for gastric cancer at the Department of Digestive Surgery, Kyoto Prefectural Uni- versity of Medicine, Japan. Of these, 33 patients un- derwent gastrectomy with lymphadenectomy for RGC. Regarding the initial gastric disease, there were 19 patients with benign disease and 14 patients with gas- tric cancer. The hospital records of these patients were reviewed retrospectively. RESULTS: Concerning the initial gastric disease, the RGC group following gastric cancer had a shorter in- terval [P 〈 0.05; gastric cancer vs benign disease: 12 (2-22) vs 30 (4-51) years] and were more frequently reconstructed by Billroth- I procedure than those fol- lowing benign lesions (P 〈 0.001). Regarding recon- struction, RGC following Billroth-]_l reconstruction showed a longer interval between surgical procedures [P 〈 0.001; Billroth-11 vs Billroth- I : 32 (5-51) vs 12 (2-36) years] and tumors were more frequently associated with benign disease (P 〈 0.001) than those following Billroth- I reconstruction. In tumor location of RGC, after Billroth- I reconstruction, RGC occurred more fre- quently near the suture line and remnant gastric wall. After Billroth- 1I reconstruction, RGC occurred more fre- quently at the anastomotic site. The duration of follow- up was significantly associated with the stage of RGC (P 〈 0.05). Patients diagnosed with early stage RGC such as stage Ⅰ-Ⅱ tended to have been followed up almost every second year. CONCLUSION: Meticulous follow-up examination and early detection of RGC might lead to a better prognosis. Based on the initial gastric disease and the procedure of reconstruction, an appropriate follow-up interval and programs might enable early detection of RGC.展开更多
AIM: To investigate the effect of lithium on proliferation of esophageal cancer (EC) cells and its preliminary mechanisms. METHODS: Eca-109 cells were treated with lithium chloride, a highly selective inhibitor of...AIM: To investigate the effect of lithium on proliferation of esophageal cancer (EC) cells and its preliminary mechanisms. METHODS: Eca-109 cells were treated with lithium chloride, a highly selective inhibitor of glycogen synthase kinase 31) (GSK-31)), at different concentrations (2-30 mmol/L) and time points (0, 2, 4, 6 and 24 h). Cell proliferative ability was evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, and Cell cycle distribution was examined by flow cytometry. Expressions of p-GSK-3β, β-catenin, cyclin B1, cdc2 and cyclin D1 protein were detected by Western blotting, and the subcellular localization of β-catenin was determined by immunofluorescence. The mRNA level of of cyclin B1 was detected by reverse transcription polymerase chain reaction (RT-PCR). RESULTS: Lithium could inhibit the proliferation of Eca-109 cells. Lithium at a concentration of 20 mmol/L lithium for 24 h produced obvious changes in the distribution of cell cycle, and increased the number of cells in G2/M phase (P 〈 0.05 vs control group). Western blotting showed that lithium inhibited GSK-β) by Ser-9 phosphorylation and stabilized free β-catenin in the cytoplasm. Immunofluorescence further confirmed that free β-catenin actively translocated to the nucleus. Horeover, lithium slightly elevated cyclin D1 protein expression, whereas lowered the cyclin B1 expression after 24 h lithium exposure and no obvious change was observed for cdc2 protein. CONCLUSION: Lithium can inhibit the proliferation of human esophageal cancer cell line Eca-109 by inducing a G2/H cell cycle arrest, which is mainly mediated through the inhibition of lithium-sensitive molecule, GSK-3β, and reduction of cyclin B1 expression.展开更多
The previous methods of figuring the numbers of chemical elements is summed up in this paper. Based on that, another two creative calculative methods are introduced as well.
Background Large-scale clinical research on the relationship between red blood cell distribution width (RDW) and intermediate-term prognosis in elderly patients with coronary artery disease (CAD) is lacking. Thus,...Background Large-scale clinical research on the relationship between red blood cell distribution width (RDW) and intermediate-term prognosis in elderly patients with coronary artery disease (CAD) is lacking. Thus, this study investigated the effects of RDW on the intermediate-term mortality of elderly patients who underwent elective percutaneous coronary intervention (PCI). Methods Data from 1891 patients 〉 65 years old underwent elective PCI from July 2009 to September 2011 were collected. Based on preoperative median RDW (12.3%), the patients were divided into two groups. The low RDW group (RDW 〈 12.3%) had 899 cases; the high RDW group (RDW 〉 12.3%) had 992 cases. The all-cause mortality rates of the two groups were compared. Results Patients in the high RDW group were more likely to be female and accompanied with diabetes, had lower hemoglobin level. The mean follow-up period was 527 days. During follow-up, 61 patients died (3.2%). The postoperative mortality of the high RDW group was significantly higher than that of the low RDW group (4.3% vs. 2.0%, P = 0.004). After adjusting other factors, multivariate Cox regression analysis revealed that preoperative high RDW was significantly associated with postoperative all-cause mortality (hazard ratio: 2.301, 95% confidence interval: 1.106-4.785, P = 0.026). Conclusions Increased RDW was an independent predictor of the increased intermediate-term all-cause mortality in elderly CAD patients after elective PCI.展开更多
Petrological,chronological and geotectonic geological analysis of Precambrian metamorphic rock in Korean Peninsula shows that the remnants(>3.4 Ga) of continental nuclei crust were formed in the Paleoarchean in the...Petrological,chronological and geotectonic geological analysis of Precambrian metamorphic rock in Korean Peninsula shows that the remnants(>3.4 Ga) of continental nuclei crust were formed in the Paleoarchean in the Rangrim Massif.In the massif,the main formation ages of continental crust range from 3.2 Ga to 2.5 Ga,its important growing period was 2.8-2.5 Ga.The subsequent expansion period of the Rangrim Massif was 2.4-2.2 Ga.The division events occurred in 1.85 Ga and in the Late Paleoproterozoic--Early Mesopro-terozoic,respectively.Since then the massif was relatively stable.However,the last division of the Rangrim Massif occurred at 793 Ma.展开更多
Odd-Even Periodic Table of Chemical Elements designed by the authors settles the position of Hydrogen and Helium, Additionally, it yields no exceptional arrangements for neither the Lanthanides, Actinide and Super Act...Odd-Even Periodic Table of Chemical Elements designed by the authors settles the position of Hydrogen and Helium, Additionally, it yields no exceptional arrangements for neither the Lanthanides, Actinide and Super Actinides nor the six empty spots and the controversy on the positions of hydrogen and helium has been settled. It plays an important role in comparing the stability of nucleons and predicting the ordinal of the terminal element.展开更多
One of most challenging problems from applying the Black-Scholes model to financial derivatives, is reconciling the deviation between the expected and observed values. This study derives an extension of the Black-Scho...One of most challenging problems from applying the Black-Scholes model to financial derivatives, is reconciling the deviation between the expected and observed values. This study derives an extension of the Black-Scholes model and recovers the real drift of binary call options from their market prices. For space-dependent real drift, we obtain stable linearization and an integral equation. We also find that using market prices of options with different strike prices enables us to identify the term structure of the real drift. Results demonstrate that our new approach can confirm the existence of arbitrage opportunities in a binary option transaction.展开更多
The authors have studied the effect of a magnetic field on Baldwin's rules. The authors have proposed a new mechanism that takes into account the effect of the angle and energy endo- or exo-cyclization. The authors p...The authors have studied the effect of a magnetic field on Baldwin's rules. The authors have proposed a new mechanism that takes into account the effect of the angle and energy endo- or exo-cyclization. The authors propose to extend the rule Bouldwin not only for sp^3-, sp^2- and sp- orbits, but and for d^1 - d^10 and f^1 - f^14 elements of I-VIII of the Periodic table.展开更多
In this paper, many new explicit and exact travelling wave solutions for Burgers-Kolmogorov-Petrovskii-Piscounov(Burgers-KPP) equations are obtained by using hyperbola function method and Wu-elimination method, which ...In this paper, many new explicit and exact travelling wave solutions for Burgers-Kolmogorov-Petrovskii-Piscounov(Burgers-KPP) equations are obtained by using hyperbola function method and Wu-elimination method, which include new singular solitary wave solutions and periodic solutions. Particular important cases of the equation, such as the generalized Burgers-Fisher equation, Burgers-Chaffee infante equation and KPP equation, the corresponding solutions can be obtained also. The method can also solve other nonlinear partial differential equations.展开更多
Due to the influence of terrain structure,meteorological conditions and various factors,there are anomalous data in automatic dependent surveillance-broadcast(ADS-B)message.The ADS-B equipment can be used for position...Due to the influence of terrain structure,meteorological conditions and various factors,there are anomalous data in automatic dependent surveillance-broadcast(ADS-B)message.The ADS-B equipment can be used for positioning of general aviation aircraft.Aim to acquire the accurate position information of aircraft and detect anomaly data,the ADS-B anomaly data detection model based on deep learning and difference of Gaussian(DoG)approach is proposed.First,according to the characteristic of ADS-B data,the ADS-B position data are transformed into the coordinate system.And the origin of the coordinate system is set up as the take-off point.Then,based on the kinematic principle,the ADS-B anomaly data can be removed.Moreover,the details of the ADS-B position data can be got by the DoG approach.Finally,the long short-term memory(LSTM)neural network is used to optimize the recurrent neural network(RNN)with severe gradient reduction for processing ADS-B data.The position data of ADS-B are reconstructed by the sequence to sequence(seq2seq)model which is composed of LSTM neural network,and the reconstruction error is used to detect the anomalous data.Based on the real flight data of general aviation aircraft,the simulation results show that the anomaly data can be detected effectively by the proposed method of reconstructing ADS-B data with the seq2seq model,and its running time is reduced.Compared with the RNN,the accuracy of anomaly detection is increased by 2.7%.The performance of the proposed model is better than that of the traditional anomaly detection models.展开更多
The binding of nuclear proteins prepared from mouse erythroid tissue in different developmental stages to the 5'-flanking regulatory elements of human β-globin gene, two negative control regions(NCR1,-610 to -490...The binding of nuclear proteins prepared from mouse erythroid tissue in different developmental stages to the 5'-flanking regulatory elements of human β-globin gene, two negative control regions(NCR1,-610 to -490 bp;NCR2, -338 to-233bp), was identified.Two stage specific protein factors corresponding to embryonic and fetal stages were found to be capable of binding to NCR2.These data provided evidence that the cis acting elements of the 5'-flanking region might be involved in the developmental control of β-globin gene and NCR2 might be responsible in part for the silence of β-globin gene in the embryonic and fetal stages.展开更多
An improved linear-time retiming algorithm is proposed to incrementally optimize the clock period, espe cially considering the influence of the in-out degree of the critical combinational elements. Firslly, the critic...An improved linear-time retiming algorithm is proposed to incrementally optimize the clock period, espe cially considering the influence of the in-out degree of the critical combinational elements. Firslly, the critical elements are selected from all the critical combinational elements to retime. Secondly, for the nodes that cannot be performed with such retiming, register sharing is implemented while the path delay is kept unchanged. The incremental algorithm can be applied with the technology mapping to minimize the critical path delay and obtain fewer registers in the re- timed circuit with the near-optimal clock period. Compared with Singh's incremental algorithm, experiments show that the proposed algorithm can reduce the flip-flop count by 11% and look-up table (LUT) count by 5% while improv- ing the minimum clock period by 6%. The runtime is also reduced by 9% of the design flow.展开更多
Concrete footbridges, due to their mass, stiffness and damping, are perceived as strucaires more resistant to vibration caused by dynamic action of the users. In order to verify the dynamic behaviour of concrete footb...Concrete footbridges, due to their mass, stiffness and damping, are perceived as strucaires more resistant to vibration caused by dynamic action of the users. In order to verify the dynamic behaviour of concrete footbridges, a series of field tests and numerical analyses have been carried out. In the paper, the results of the dynamic field tests of three medium span concrete footbridges with different structural systems (frame, beam and arch footbridges) and their dynamic characteristics (mass, stiffness and damping) are presented. The field tests were carried out for different types of vibration excitation caused by walking, running and jumping persons. Furthermore, the vibrational comfort criteria for footbridges are shortly described and verified for examined structures. The study were supplemented by numerical calculation of natural mode shapes and frequencies of the structures using the 3D FEA (finite element analysis) models with elastic supports elements in order to ensure the compatibility of the calculated and measured mode shapes of the footbridges.展开更多
Based on the analysis of the basic characteristics for the gob site in Northern Shaanxi Province and the room and pillar mining way about coal mine, the variety rule of the coal beds below the site was studied by the ...Based on the analysis of the basic characteristics for the gob site in Northern Shaanxi Province and the room and pillar mining way about coal mine, the variety rule of the coal beds below the site was studied by the using of FEM during the process of coal mining. The statuses of the stresses and strains and the varieties of the plastic area were simulated in the whole rock and coal pillars. The characters of stresses and deformation of the gob area of the coalmine were analyzed and evaluated after the site built in weathering. Moreover, the long-term stability of the gob area was predicted. As a result, the deformation of the gob area under the site is not been finished, and there is the danger that the gob site will collapsing as a whole; therefore, relative measures must be taken.展开更多
By using the theory of coincidence degree, we study a kind of periodic solutions to second order differential equation with a deviating argument such as x″(t) + f(x′(t)) + h(x(t))x′(t) + g(x(t - τ...By using the theory of coincidence degree, we study a kind of periodic solutions to second order differential equation with a deviating argument such as x″(t) + f(x′(t)) + h(x(t))x′(t) + g(x(t - τ(t))) ≈ p(t), some sufficient conditions on the existence of periodic solutions are obtained.展开更多
文摘AIM: TO re-evaluate the recent clinicopathological fea- tures of remnant gastric cancer (RGC) and to develop desirable surveillance programs.METHODS: Between 1997 and 2008, 1149 patients underwent gastrectomy for gastric cancer at the Department of Digestive Surgery, Kyoto Prefectural Uni- versity of Medicine, Japan. Of these, 33 patients un- derwent gastrectomy with lymphadenectomy for RGC. Regarding the initial gastric disease, there were 19 patients with benign disease and 14 patients with gas- tric cancer. The hospital records of these patients were reviewed retrospectively. RESULTS: Concerning the initial gastric disease, the RGC group following gastric cancer had a shorter in- terval [P 〈 0.05; gastric cancer vs benign disease: 12 (2-22) vs 30 (4-51) years] and were more frequently reconstructed by Billroth- I procedure than those fol- lowing benign lesions (P 〈 0.001). Regarding recon- struction, RGC following Billroth-]_l reconstruction showed a longer interval between surgical procedures [P 〈 0.001; Billroth-11 vs Billroth- I : 32 (5-51) vs 12 (2-36) years] and tumors were more frequently associated with benign disease (P 〈 0.001) than those following Billroth- I reconstruction. In tumor location of RGC, after Billroth- I reconstruction, RGC occurred more fre- quently near the suture line and remnant gastric wall. After Billroth- 1I reconstruction, RGC occurred more fre- quently at the anastomotic site. The duration of follow- up was significantly associated with the stage of RGC (P 〈 0.05). Patients diagnosed with early stage RGC such as stage Ⅰ-Ⅱ tended to have been followed up almost every second year. CONCLUSION: Meticulous follow-up examination and early detection of RGC might lead to a better prognosis. Based on the initial gastric disease and the procedure of reconstruction, an appropriate follow-up interval and programs might enable early detection of RGC.
基金The Innovation Project of Central South University, No. 2340-76208
文摘AIM: To investigate the effect of lithium on proliferation of esophageal cancer (EC) cells and its preliminary mechanisms. METHODS: Eca-109 cells were treated with lithium chloride, a highly selective inhibitor of glycogen synthase kinase 31) (GSK-31)), at different concentrations (2-30 mmol/L) and time points (0, 2, 4, 6 and 24 h). Cell proliferative ability was evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, and Cell cycle distribution was examined by flow cytometry. Expressions of p-GSK-3β, β-catenin, cyclin B1, cdc2 and cyclin D1 protein were detected by Western blotting, and the subcellular localization of β-catenin was determined by immunofluorescence. The mRNA level of of cyclin B1 was detected by reverse transcription polymerase chain reaction (RT-PCR). RESULTS: Lithium could inhibit the proliferation of Eca-109 cells. Lithium at a concentration of 20 mmol/L lithium for 24 h produced obvious changes in the distribution of cell cycle, and increased the number of cells in G2/M phase (P 〈 0.05 vs control group). Western blotting showed that lithium inhibited GSK-β) by Ser-9 phosphorylation and stabilized free β-catenin in the cytoplasm. Immunofluorescence further confirmed that free β-catenin actively translocated to the nucleus. Horeover, lithium slightly elevated cyclin D1 protein expression, whereas lowered the cyclin B1 expression after 24 h lithium exposure and no obvious change was observed for cdc2 protein. CONCLUSION: Lithium can inhibit the proliferation of human esophageal cancer cell line Eca-109 by inducing a G2/H cell cycle arrest, which is mainly mediated through the inhibition of lithium-sensitive molecule, GSK-3β, and reduction of cyclin B1 expression.
基金This work is supported by the National Science Foundation of China (No. 20471001 and 20671001), the Important Project of Anhui Provincial Education Department (No. ZD2007004-1), the Specific Project for Talents of Science and Technology of Universities of Anhui Province (No. 2005hbz03) and the Key Laboratory of Environment-friendly Polymer Materials of Anhui Province.
文摘The previous methods of figuring the numbers of chemical elements is summed up in this paper. Based on that, another two creative calculative methods are introduced as well.
文摘Background Large-scale clinical research on the relationship between red blood cell distribution width (RDW) and intermediate-term prognosis in elderly patients with coronary artery disease (CAD) is lacking. Thus, this study investigated the effects of RDW on the intermediate-term mortality of elderly patients who underwent elective percutaneous coronary intervention (PCI). Methods Data from 1891 patients 〉 65 years old underwent elective PCI from July 2009 to September 2011 were collected. Based on preoperative median RDW (12.3%), the patients were divided into two groups. The low RDW group (RDW 〈 12.3%) had 899 cases; the high RDW group (RDW 〉 12.3%) had 992 cases. The all-cause mortality rates of the two groups were compared. Results Patients in the high RDW group were more likely to be female and accompanied with diabetes, had lower hemoglobin level. The mean follow-up period was 527 days. During follow-up, 61 patients died (3.2%). The postoperative mortality of the high RDW group was significantly higher than that of the low RDW group (4.3% vs. 2.0%, P = 0.004). After adjusting other factors, multivariate Cox regression analysis revealed that preoperative high RDW was significantly associated with postoperative all-cause mortality (hazard ratio: 2.301, 95% confidence interval: 1.106-4.785, P = 0.026). Conclusions Increased RDW was an independent predictor of the increased intermediate-term all-cause mortality in elderly CAD patients after elective PCI.
文摘Petrological,chronological and geotectonic geological analysis of Precambrian metamorphic rock in Korean Peninsula shows that the remnants(>3.4 Ga) of continental nuclei crust were formed in the Paleoarchean in the Rangrim Massif.In the massif,the main formation ages of continental crust range from 3.2 Ga to 2.5 Ga,its important growing period was 2.8-2.5 Ga.The subsequent expansion period of the Rangrim Massif was 2.4-2.2 Ga.The division events occurred in 1.85 Ga and in the Late Paleoproterozoic--Early Mesopro-terozoic,respectively.Since then the massif was relatively stable.However,the last division of the Rangrim Massif occurred at 793 Ma.
文摘Odd-Even Periodic Table of Chemical Elements designed by the authors settles the position of Hydrogen and Helium, Additionally, it yields no exceptional arrangements for neither the Lanthanides, Actinide and Super Actinides nor the six empty spots and the controversy on the positions of hydrogen and helium has been settled. It plays an important role in comparing the stability of nucleons and predicting the ordinal of the terminal element.
文摘One of most challenging problems from applying the Black-Scholes model to financial derivatives, is reconciling the deviation between the expected and observed values. This study derives an extension of the Black-Scholes model and recovers the real drift of binary call options from their market prices. For space-dependent real drift, we obtain stable linearization and an integral equation. We also find that using market prices of options with different strike prices enables us to identify the term structure of the real drift. Results demonstrate that our new approach can confirm the existence of arbitrage opportunities in a binary option transaction.
文摘The authors have studied the effect of a magnetic field on Baldwin's rules. The authors have proposed a new mechanism that takes into account the effect of the angle and energy endo- or exo-cyclization. The authors propose to extend the rule Bouldwin not only for sp^3-, sp^2- and sp- orbits, but and for d^1 - d^10 and f^1 - f^14 elements of I-VIII of the Periodic table.
基金Supported by the National Key Basic Research Development Project of China(1998030600)Supported by the National Natural Science Foudation of China(10072013)Supported by the Educational Commmittee of Liaoning Province(990421093)
文摘In this paper, many new explicit and exact travelling wave solutions for Burgers-Kolmogorov-Petrovskii-Piscounov(Burgers-KPP) equations are obtained by using hyperbola function method and Wu-elimination method, which include new singular solitary wave solutions and periodic solutions. Particular important cases of the equation, such as the generalized Burgers-Fisher equation, Burgers-Chaffee infante equation and KPP equation, the corresponding solutions can be obtained also. The method can also solve other nonlinear partial differential equations.
基金supported by the National Key R&D Program of China(No.2018AAA0100804)the Talent Project of Revitalization Liaoning(No.XLYC1907022)+5 种基金the Key R&D Projects of Liaoning Province(No.2020JH2/10100045)the Capacity Building of Civil Aviation Safety(No.TMSA1614)the Natural Science Foundation of Liaoning Province(No.2019-MS-251)the Scientific Research Project of Liaoning Provincial Department of Education(Nos.L201705,L201716)the High-Level Innovation Talent Project of Shenyang(No.RC190030)the Second Young and Middle-Aged Talents Support Program of Shenyang Aerospace University.
文摘Due to the influence of terrain structure,meteorological conditions and various factors,there are anomalous data in automatic dependent surveillance-broadcast(ADS-B)message.The ADS-B equipment can be used for positioning of general aviation aircraft.Aim to acquire the accurate position information of aircraft and detect anomaly data,the ADS-B anomaly data detection model based on deep learning and difference of Gaussian(DoG)approach is proposed.First,according to the characteristic of ADS-B data,the ADS-B position data are transformed into the coordinate system.And the origin of the coordinate system is set up as the take-off point.Then,based on the kinematic principle,the ADS-B anomaly data can be removed.Moreover,the details of the ADS-B position data can be got by the DoG approach.Finally,the long short-term memory(LSTM)neural network is used to optimize the recurrent neural network(RNN)with severe gradient reduction for processing ADS-B data.The position data of ADS-B are reconstructed by the sequence to sequence(seq2seq)model which is composed of LSTM neural network,and the reconstruction error is used to detect the anomalous data.Based on the real flight data of general aviation aircraft,the simulation results show that the anomaly data can be detected effectively by the proposed method of reconstructing ADS-B data with the seq2seq model,and its running time is reduced.Compared with the RNN,the accuracy of anomaly detection is increased by 2.7%.The performance of the proposed model is better than that of the traditional anomaly detection models.
基金gramts from shanghai Joint Laboratory of Life sciences,Academia Sinica,and the National National sciences Foundation,
文摘The binding of nuclear proteins prepared from mouse erythroid tissue in different developmental stages to the 5'-flanking regulatory elements of human β-globin gene, two negative control regions(NCR1,-610 to -490 bp;NCR2, -338 to-233bp), was identified.Two stage specific protein factors corresponding to embryonic and fetal stages were found to be capable of binding to NCR2.These data provided evidence that the cis acting elements of the 5'-flanking region might be involved in the developmental control of β-globin gene and NCR2 might be responsible in part for the silence of β-globin gene in the embryonic and fetal stages.
基金Supported by Major National Scientific Research Plan (No. 2011CB933202)
文摘An improved linear-time retiming algorithm is proposed to incrementally optimize the clock period, espe cially considering the influence of the in-out degree of the critical combinational elements. Firslly, the critical elements are selected from all the critical combinational elements to retime. Secondly, for the nodes that cannot be performed with such retiming, register sharing is implemented while the path delay is kept unchanged. The incremental algorithm can be applied with the technology mapping to minimize the critical path delay and obtain fewer registers in the re- timed circuit with the near-optimal clock period. Compared with Singh's incremental algorithm, experiments show that the proposed algorithm can reduce the flip-flop count by 11% and look-up table (LUT) count by 5% while improv- ing the minimum clock period by 6%. The runtime is also reduced by 9% of the design flow.
文摘Concrete footbridges, due to their mass, stiffness and damping, are perceived as strucaires more resistant to vibration caused by dynamic action of the users. In order to verify the dynamic behaviour of concrete footbridges, a series of field tests and numerical analyses have been carried out. In the paper, the results of the dynamic field tests of three medium span concrete footbridges with different structural systems (frame, beam and arch footbridges) and their dynamic characteristics (mass, stiffness and damping) are presented. The field tests were carried out for different types of vibration excitation caused by walking, running and jumping persons. Furthermore, the vibrational comfort criteria for footbridges are shortly described and verified for examined structures. The study were supplemented by numerical calculation of natural mode shapes and frequencies of the structures using the 3D FEA (finite element analysis) models with elastic supports elements in order to ensure the compatibility of the calculated and measured mode shapes of the footbridges.
文摘Based on the analysis of the basic characteristics for the gob site in Northern Shaanxi Province and the room and pillar mining way about coal mine, the variety rule of the coal beds below the site was studied by the using of FEM during the process of coal mining. The statuses of the stresses and strains and the varieties of the plastic area were simulated in the whole rock and coal pillars. The characters of stresses and deformation of the gob area of the coalmine were analyzed and evaluated after the site built in weathering. Moreover, the long-term stability of the gob area was predicted. As a result, the deformation of the gob area under the site is not been finished, and there is the danger that the gob site will collapsing as a whole; therefore, relative measures must be taken.
基金the Natural Science Foundation of Anhui Province(050460103)the Natural Science Foundation by the Bureau of Education of Anhui Province(2005kj031ZD)
文摘By using the theory of coincidence degree, we study a kind of periodic solutions to second order differential equation with a deviating argument such as x″(t) + f(x′(t)) + h(x(t))x′(t) + g(x(t - τ(t))) ≈ p(t), some sufficient conditions on the existence of periodic solutions are obtained.