For regional ecological management,it is important to evaluate the quality of ecosystems and analyze the underlying causes of ecological changes.Using the Google Earth Engine(GEE)platform,the remote sensing ecological...For regional ecological management,it is important to evaluate the quality of ecosystems and analyze the underlying causes of ecological changes.Using the Google Earth Engine(GEE)platform,the remote sensing ecological index(RSEI)was calculated for the Lijiang River Basin in Guangxi Zhuang Autonomous Region for 1991,2001,2011,and 2021.Spatial autocorrelation analysis was employed to investigate spatiotemporal variations in the ecological environmental quality of the Lijiang River Basin.Furthermore,geographic detectors were used to quantitatively analyze influencing factors and their interaction effects on ecological environmental quality.The results verified that:1)From 1991 to 2021,the ecological environmental quality of the Lijiang River Basin demonstrated significant improvement.The area with good and excellent ecological environmental quality in proportion increased by 19.69%(3406.57 km^(2)),while the area with fair and poor ecological environmental quality in proportion decreased by 10.76%(1860.36 km^(2)).2)Spatially,the ecological environmental quality of the Lijiang River Basin exhibited a pattern of low quality in the central region and high quality in the periphery.Specifically,poor ecological environmental quality characterized the Guilin urban area,Pingle County,and Lingchuan County.3)From 1991 to 2021,a significant positive spatial correlation was observed in ecological environmental quality of the Lijiang River Basin.Areas with high-high agglomeration were predominantly forests and grasslands,indicating good ecological environmental quality,whereas areas with low-low agglomeration were dominated by cultivated land and construction land,indicating poor ecological environmental quality.4)Annual average precipitation and temperature exerted the most significant influence on the ecological environmental quality of the basin,and their interactions with other factors had the great influence.This study aimed to enhance understanding of the evolution of the ecological environment in the Lijiang River Basin of Guangxi Zhuang Autonomous Region and provide scientific guidance for decision-making and management related to ecology in the region.展开更多
The most prospective method for certain structural failures and damages that cannot employ redundancy is self-repairing techniques, to ensure especially the maximum flight safety. Based on the characters of self-repai...The most prospective method for certain structural failures and damages that cannot employ redundancy is self-repairing techniques, to ensure especially the maximum flight safety. Based on the characters of self-repairing aircraft, this paper states some basic assumptions of the self-repairing aircraft, and puts forward some special new conceptions concerning the self-repairing aircraft: control input, operating input, command input, repair input and operating and control factor as well as their relationships. Thus it provides a simple and reliable mathematical model structure for the research on the self-repairing control of the aircraft.展开更多
Aim To build an adaptive fuzzy neural controller and simulate it. Methods\ Fuzzy logic and back propagation(BP) algorithm are combined to utilize their advantages while avoiding the disadvantages. Results and Conclus...Aim To build an adaptive fuzzy neural controller and simulate it. Methods\ Fuzzy logic and back propagation(BP) algorithm are combined to utilize their advantages while avoiding the disadvantages. Results and Conclusion\ Simulation results of the third order plant with disturbances and dead times show the validity of the presented controller. The presented controller can control cases that preceding controllers were unable to control.展开更多
For any given positive integer n ≥ 1, the Euler function φ（n） is defined to be the number of positive integers not exceeding n which are relatively prime to n. w（n） is defined to be the number of different prime...For any given positive integer n ≥ 1, the Euler function φ（n） is defined to be the number of positive integers not exceeding n which are relatively prime to n. w（n） is defined to be the number of different prime divisors of n. Some kind of equations involving Euler＇s function is studied in the paper.展开更多
Let G be a graph, and g and f be integer valued functions defined on V(G) which satisfy g(x)≤f(x) and g(x)≡f(x)(mod 2) for all x∈V(G). Then a spanning subgraph F of G is called a {g,g+2,…,f} -factor if deg_F(x)∈{...Let G be a graph, and g and f be integer valued functions defined on V(G) which satisfy g(x)≤f(x) and g(x)≡f(x)(mod 2) for all x∈V(G). Then a spanning subgraph F of G is called a {g,g+2,…,f} -factor if deg_F(x)∈{g(x),g(x)+2,…,f(x)} for all x∈V(G), when g(x)=1 for all x∈V(G), such a factor is called (1,f) -odd-factor. We give necessary and sufficient conditions for a graph G to have a {g,g+2,…,f} -factor and a (1,f) -odd-factor which contains an arbitrarily given edge of G, from that we derive some interesting results.展开更多
Objective To investigate the expression levels of serum hypoxia inducible factor 1 alpha(HIF-1α) and vascular endothelial growth factor(VEGF) pre-and post-transcatheter arterial chemoembolization(TACE) in patients wi...Objective To investigate the expression levels of serum hypoxia inducible factor 1 alpha(HIF-1α) and vascular endothelial growth factor(VEGF) pre-and post-transcatheter arterial chemoembolization(TACE) in patients with primary liver cancer(PLC),and correlations between prognosis factors and serum HIF-1α as well as VEGF levels.Methods Forty consecutive patients fulfilling diagnostic criteria for PLC undergoing TACE from March 2008 to May 2009 were enrolled into the study.The serum HIF-1α and VEGF levels of PLC patients pre-and 1 day,1 week,1 month post-TACE were analyzed using ELISA,and compared with that of 20 healthy volunteers.Patients were divided into complete response(CR) and partial response(PR),stable disease(SD),progressive disease(PD) groups according to the therapeutic efficacy.Pearson correlation was used to analyze the correlation between different clinical variables and serum HIF-1α and VEGF levels before TACE,and correlation between serum HIF-1α and VEGF levels was also evaluated.Results The expression levels of serum HIF-1α and VEGF in PLC patients were 154.94±83.29 and 264.00±148.10 pg/mL pre-TACE,and both of them were significantly higher than those in control group(23.84±8.15 and 69.78±21.42 pg/mL,all P<0.01).One day after TACE,both serum HIF-1α(570.64± 230.87 pg/mL) and VEGF levels(362.07±102.25 pg/mL) reached the peak values(all P<0.01).One week post-TACE,expression levels of them were decreased(198.62±92.11 and 283.52±145.46 pg/mL respectively),but still significantly higher than those before TACE(all P<0.01).The levels of both HIF-1α(133.96±57.02 vs.255.74±123.44 pg/mL) and VEGF(150.96±84.89 vs.368.95±161.90 pg/mL) in CR group 1 month post-TACE were significantly lower than those in PR+SD+PD group(all P<0.01).The level of serum HIF-1α was positively correlated with serum VEGF level(r=0.42,P<0.001).Both serum HIF-1α and VEGF levels were observed to be correlated with portal vein tumor thrombi(P<0.05) and metastasis(P<0.05).展开更多
By using the simplified method of factorization given by Valli, and the correspondence between the harmonic map φ∶S 2→U(N) and U(N) uniton bundle ν(φ) with energy corresponding to the bundles’ seco...By using the simplified method of factorization given by Valli, and the correspondence between the harmonic map φ∶S 2→U(N) and U(N) uniton bundle ν(φ) with energy corresponding to the bundles’ second Chern class, which is established by Anand, the energy in a case φ∶S 2→U(N) is investigated in order to estimate the energy of a uniton using the uniton number. It is proved that Uhlenbeck’s factorization is energy decreasing. And a method of estimating the energy of a uniton by the uniton number is given.展开更多
Objectives Inflammation has been shown to be related with acute aortic dissection （AAD）. The present study aimed to evaluate the association of white blood cell counts （WI3Cc） on admission with both in-hospital an...Objectives Inflammation has been shown to be related with acute aortic dissection （AAD）. The present study aimed to evaluate the association of white blood cell counts （WI3Cc） on admission with both in-hospital and long-term all-cause mortality in patients with uncom- plicated Stanford type B AAD. Methods From 2008 to 2010, a total of 377 consecutive patients with uncomplicated type B AAD were enrolled and then followed up. Clinical data and WBCc on admission were collected. The primary end points were in-hospital death and long-term all-cause death. Results The in-hospital death rate was 4.2%, and the long-term all-cause mortality rate was 6.9% during a median follow-up of 18.9 months. WBCc on admission was identified as a risk factor for in-hospital death by univariate Cox regression analysis as both a continuous variable and a categorical variable using a cut off of 11.0 × 109 cell/L （all P 〈 0.05）. After adjusting for age, sex and other risk factors, elevated admission WBCc was still a significant predictor for in-hospital death as both a continuous variable [hazard ratio （HR）： 1.052, 95% CI： 1.024-1.336, P = 0.002] and a categorical variable using a cut off of 11.0 × 109 cell/L （HR： 2.056, 95% CI： 1.673-5.253, P = 0.034）. No relationship was observed between WBCc on admission and long-term all-cause death. Conclusions Our results indicate that elevated WBCc upon admission might be used as a predictor for increased risk of in-hospital death in uncomplicated type B AAD. There might be no predictive value of WBCc for the long-term survival of type B AAD.展开更多
In this paper, we show that the invertible operator T, which is a bounded linear functional on a separable Hilbert space H, could factor as T = US, where U is unitary and S belongs to width-two CSL algebra algφ （φ ...In this paper, we show that the invertible operator T, which is a bounded linear functional on a separable Hilbert space H, could factor as T = US, where U is unitary and S belongs to width-two CSL algebra algφ （φ = M∨N） when nest M or N is a countable nest, or S belongs to algφ^-1 when nests M and N are countable nests. For the factorization of nest,we obtain that T factors as T = US where S ∈ DN^-1 and U is unitary as N be a countable nest.展开更多
基金supported by the Guangxi Natural Science Foundation(2020GXNSFAA297266)Doctoral Research Foundation of Guilin University of Technology(GUTQDJJ2007059)Guangxi Hidden Metallic Mineral Exploration Key Laboratory。
文摘For regional ecological management,it is important to evaluate the quality of ecosystems and analyze the underlying causes of ecological changes.Using the Google Earth Engine(GEE)platform,the remote sensing ecological index(RSEI)was calculated for the Lijiang River Basin in Guangxi Zhuang Autonomous Region for 1991,2001,2011,and 2021.Spatial autocorrelation analysis was employed to investigate spatiotemporal variations in the ecological environmental quality of the Lijiang River Basin.Furthermore,geographic detectors were used to quantitatively analyze influencing factors and their interaction effects on ecological environmental quality.The results verified that:1)From 1991 to 2021,the ecological environmental quality of the Lijiang River Basin demonstrated significant improvement.The area with good and excellent ecological environmental quality in proportion increased by 19.69%(3406.57 km^(2)),while the area with fair and poor ecological environmental quality in proportion decreased by 10.76%(1860.36 km^(2)).2)Spatially,the ecological environmental quality of the Lijiang River Basin exhibited a pattern of low quality in the central region and high quality in the periphery.Specifically,poor ecological environmental quality characterized the Guilin urban area,Pingle County,and Lingchuan County.3)From 1991 to 2021,a significant positive spatial correlation was observed in ecological environmental quality of the Lijiang River Basin.Areas with high-high agglomeration were predominantly forests and grasslands,indicating good ecological environmental quality,whereas areas with low-low agglomeration were dominated by cultivated land and construction land,indicating poor ecological environmental quality.4)Annual average precipitation and temperature exerted the most significant influence on the ecological environmental quality of the basin,and their interactions with other factors had the great influence.This study aimed to enhance understanding of the evolution of the ecological environment in the Lijiang River Basin of Guangxi Zhuang Autonomous Region and provide scientific guidance for decision-making and management related to ecology in the region.
文摘The most prospective method for certain structural failures and damages that cannot employ redundancy is self-repairing techniques, to ensure especially the maximum flight safety. Based on the characters of self-repairing aircraft, this paper states some basic assumptions of the self-repairing aircraft, and puts forward some special new conceptions concerning the self-repairing aircraft: control input, operating input, command input, repair input and operating and control factor as well as their relationships. Thus it provides a simple and reliable mathematical model structure for the research on the self-repairing control of the aircraft.
文摘Aim To build an adaptive fuzzy neural controller and simulate it. Methods\ Fuzzy logic and back propagation(BP) algorithm are combined to utilize their advantages while avoiding the disadvantages. Results and Conclusion\ Simulation results of the third order plant with disturbances and dead times show the validity of the presented controller. The presented controller can control cases that preceding controllers were unable to control.
基金Foundation item： Supported by the National Natural Science Foundation of China（10671056）
文摘For any given positive integer n ≥ 1, the Euler function φ（n） is defined to be the number of positive integers not exceeding n which are relatively prime to n. w（n） is defined to be the number of different prime divisors of n. Some kind of equations involving Euler＇s function is studied in the paper.
文摘Let G be a graph, and g and f be integer valued functions defined on V(G) which satisfy g(x)≤f(x) and g(x)≡f(x)(mod 2) for all x∈V(G). Then a spanning subgraph F of G is called a {g,g+2,…,f} -factor if deg_F(x)∈{g(x),g(x)+2,…,f(x)} for all x∈V(G), when g(x)=1 for all x∈V(G), such a factor is called (1,f) -odd-factor. We give necessary and sufficient conditions for a graph G to have a {g,g+2,…,f} -factor and a (1,f) -odd-factor which contains an arbitrarily given edge of G, from that we derive some interesting results.
文摘Objective To investigate the expression levels of serum hypoxia inducible factor 1 alpha(HIF-1α) and vascular endothelial growth factor(VEGF) pre-and post-transcatheter arterial chemoembolization(TACE) in patients with primary liver cancer(PLC),and correlations between prognosis factors and serum HIF-1α as well as VEGF levels.Methods Forty consecutive patients fulfilling diagnostic criteria for PLC undergoing TACE from March 2008 to May 2009 were enrolled into the study.The serum HIF-1α and VEGF levels of PLC patients pre-and 1 day,1 week,1 month post-TACE were analyzed using ELISA,and compared with that of 20 healthy volunteers.Patients were divided into complete response(CR) and partial response(PR),stable disease(SD),progressive disease(PD) groups according to the therapeutic efficacy.Pearson correlation was used to analyze the correlation between different clinical variables and serum HIF-1α and VEGF levels before TACE,and correlation between serum HIF-1α and VEGF levels was also evaluated.Results The expression levels of serum HIF-1α and VEGF in PLC patients were 154.94±83.29 and 264.00±148.10 pg/mL pre-TACE,and both of them were significantly higher than those in control group(23.84±8.15 and 69.78±21.42 pg/mL,all P<0.01).One day after TACE,both serum HIF-1α(570.64± 230.87 pg/mL) and VEGF levels(362.07±102.25 pg/mL) reached the peak values(all P<0.01).One week post-TACE,expression levels of them were decreased(198.62±92.11 and 283.52±145.46 pg/mL respectively),but still significantly higher than those before TACE(all P<0.01).The levels of both HIF-1α(133.96±57.02 vs.255.74±123.44 pg/mL) and VEGF(150.96±84.89 vs.368.95±161.90 pg/mL) in CR group 1 month post-TACE were significantly lower than those in PR+SD+PD group(all P<0.01).The level of serum HIF-1α was positively correlated with serum VEGF level(r=0.42,P<0.001).Both serum HIF-1α and VEGF levels were observed to be correlated with portal vein tumor thrombi(P<0.05) and metastasis(P<0.05).
文摘By using the simplified method of factorization given by Valli, and the correspondence between the harmonic map φ∶S 2→U(N) and U(N) uniton bundle ν(φ) with energy corresponding to the bundles’ second Chern class, which is established by Anand, the energy in a case φ∶S 2→U(N) is investigated in order to estimate the energy of a uniton using the uniton number. It is proved that Uhlenbeck’s factorization is energy decreasing. And a method of estimating the energy of a uniton by the uniton number is given.
基金We are very grateful to the patients and doctors who participated in the study and for the help and co-operation of the clinic staff. This work was supported by a grant from the National Natural Science Foundation of China to Dr. FAN XH （No. 81570430）.
文摘Objectives Inflammation has been shown to be related with acute aortic dissection （AAD）. The present study aimed to evaluate the association of white blood cell counts （WI3Cc） on admission with both in-hospital and long-term all-cause mortality in patients with uncom- plicated Stanford type B AAD. Methods From 2008 to 2010, a total of 377 consecutive patients with uncomplicated type B AAD were enrolled and then followed up. Clinical data and WBCc on admission were collected. The primary end points were in-hospital death and long-term all-cause death. Results The in-hospital death rate was 4.2%, and the long-term all-cause mortality rate was 6.9% during a median follow-up of 18.9 months. WBCc on admission was identified as a risk factor for in-hospital death by univariate Cox regression analysis as both a continuous variable and a categorical variable using a cut off of 11.0 × 109 cell/L （all P 〈 0.05）. After adjusting for age, sex and other risk factors, elevated admission WBCc was still a significant predictor for in-hospital death as both a continuous variable [hazard ratio （HR）： 1.052, 95% CI： 1.024-1.336, P = 0.002] and a categorical variable using a cut off of 11.0 × 109 cell/L （HR： 2.056, 95% CI： 1.673-5.253, P = 0.034）. No relationship was observed between WBCc on admission and long-term all-cause death. Conclusions Our results indicate that elevated WBCc upon admission might be used as a predictor for increased risk of in-hospital death in uncomplicated type B AAD. There might be no predictive value of WBCc for the long-term survival of type B AAD.
基金Supported by the National Science Foundation of China(90205019)
文摘In this paper, we show that the invertible operator T, which is a bounded linear functional on a separable Hilbert space H, could factor as T = US, where U is unitary and S belongs to width-two CSL algebra algφ （φ = M∨N） when nest M or N is a countable nest, or S belongs to algφ^-1 when nests M and N are countable nests. For the factorization of nest,we obtain that T factors as T = US where S ∈ DN^-1 and U is unitary as N be a countable nest.
