BACKGROUND The level of Ki-67 expression has served as a prognostic factor in gastric cancer.The quantitative parameters based on the novel dual-layer spectral detector computed tomography(DLSDCT)in discriminating the...BACKGROUND The level of Ki-67 expression has served as a prognostic factor in gastric cancer.The quantitative parameters based on the novel dual-layer spectral detector computed tomography(DLSDCT)in discriminating the Ki-67 expression status are unclear.AIM To investigate the diagnostic ability of DLSDCT-derived parameters for Ki-67 expression status in gastric carcinoma(GC).METHODS Dual-phase enhanced abdominal DLSDCT was performed preoperatively in 108 patients with gastric adenocarcinoma.Primary tumor monoenergetic CT attenuation value at 40-100 kilo electron volt(kev),the slope of the spectral curve(λ_(HU)),iodine concentration(IC),normalized IC(nIC),effective atomic number(Z^(eff))and normalized Z^(eff)(nZ^(eff))in the arterial phase(AP)and venous phase(VP)were retrospectively compared between patients with low and high Ki-67 expression in gastric adenocarcinoma.Spearman’s correlation coefficient was used to analyze the association between the above parameters and Ki-67 expression status.Receiver operating characteristic(ROC)curve analysis was performed to compare the diagnostic efficacy of the statistically significant parameters between two groups.RESULTS Thirty-seven and 71 patients were classified as having low and high Ki-67 expression,respectively.CT_(40 kev-VP),CT_(70 kev-VP),CT_(100 kev-VP),and Z^(eff)-related parameters were significantly higher,but IC-related parameters were lower in the group with low Ki-67 expression status than the group with high Ki-67 expression status,and other analyzed parameters showed no statistical difference between the two groups.Spearman’s correlation analysis showed that CT_(40 kev-VP),CT_(70 kev-VP),CT_(100 kev-VP),Z^(eff),and n Z^(eff) exhibited a negative correlation with Ki-67 status,whereas IC and nIC had positive correlation with Ki-67 status.The ROC analysis demonstrated that the multi-variable model of spectral parameters performed well in identifying the Ki-67 status[area under the curve(AUC)=0.967;sensitivity 95.77%;specificity 91.89%)].Nevertheless,the differentiating capabilities of singlevariable model were moderate(AUC value 0.630-0.835).In addition,the nZ_(VP)^(eff) and nIC_(VP)(AUC 0.835 and 0.805)showed better performance than CT_(40 kev-VP),CT_(70 kev-VP) and CT_(100 kev-VP)(AUC 0.630,0.631 and 0.662)in discriminating the Ki-67 status.CONCLUSION Quantitative spectral parameters are feasible to distinguish low and high Ki-67 expression in gastric adenocarcinoma.Z^(eff) and IC may be useful parameters for evaluating the Ki-67 expression.展开更多
The statistical probability and their variation regularity of the measurable characteristic parameters in the CO 2 arc welding droplet short circuiting transfer process have been studied. The statistical analysis sh...The statistical probability and their variation regularity of the measurable characteristic parameters in the CO 2 arc welding droplet short circuiting transfer process have been studied. The statistical analysis shows that the sensitivity of each characteristic parameter with regard to the variation of the short circuiting transfer process is different. The sensitivity of 4 kinds among these characteristic parameters is more intense than that of the short circuiting transfer frequency. In order to take account of the synthetic influence of these characteristic parameters, by means of the characteristic parameters synthetic value, a quantitative evaluation function is built up to describe and evaluate the short circuiting transfer process of CO 2 arc welding in real time. The testing shows that the evaluation function can give a suitable synthetic valuation for the short circuiting transfer process with a variety of welding variables.展开更多
It is important to calibrate micro-parameters for applying partied flow code(PFC)to study mechanical characteristics and failure mechanism of rock materials.Uniform design method is firstly adopted to determine the mi...It is important to calibrate micro-parameters for applying partied flow code(PFC)to study mechanical characteristics and failure mechanism of rock materials.Uniform design method is firstly adopted to determine the microscopic parameters of parallel-bonded particle model for three-dimensional discrete element particle flow code(PFC3D).Variation ranges of microscopic of the microscopic parameters are created by analyzing the effects of microscopic parameters on macroscopic parameters(elastic modulus E,Poisson ratio v,uniaxial compressive strengthσc,and ratio of crack initial stress to uniaxial compressive strengthσci/σc)in order to obtain the actual uniform design talbe.The calculation equations of the microscopic and macroscopic parameters of rock materials can be established by the actual uniform design table and the regression analysis and thus the PFC3D microscopic parameters can be quantitatively determined.The PFC3D simulated results of the intact and pre-cracked rock specimens under uniaxial and triaxial compressions(including the macroscopic mechanical parameters,stress−strain curves and failure process)are in good agreement with experimental results,which can prove the validity of the calculation equations of microscopic and macroscopic parameters.展开更多
Our expedition have identified location in the central part of Kosovo where were collected a samples （accessions） at coordinates; Sub-Locality SL-1 （N42°34′36″, E21°07′45″）, altitude 574 m, SL-2 （N4...Our expedition have identified location in the central part of Kosovo where were collected a samples （accessions） at coordinates; Sub-Locality SL-1 （N42°34′36″, E21°07′45″）, altitude 574 m, SL-2 （N42°34′29″, E 21°07′45″altitude 591 m and SL-3 （N42°34′30″, E21°07′46″） on altitude 565 m. The aim of present investigation was carried out to study genetic variability of quantitative and qualitative parameters. The populations from SL-2 were characterized of higher significance on seed oil （23.74%） and protein content （16.74%）. The estimation average value of seed protein and oil content was 15.52% and 23.48% respectively. The variability of plant height ranged from 182.33 cm to as much as 200.89 cm, while distinction＇s between them were ＋ 18.56 cm which was a significant higher at P〈0.05 probability level. The SL-3 showed the higher value of HWK （34.6 g）, head per plant （39.33） and head diameter （9.5 cm） but, was characterized significantly lowest on seed protein content （13.99%）. The all traits included in our investigations showed a higher genetic variability with majority of extreme values. The sunflower populations differed significantly in several parameters measured, they have a different genetic and morphological backgrounds. Results from wild sunflower form indicated notable differences in dispersion of important genes for different traits and showed the potential for using in future for breeding program.展开更多
Based on the principle of the electric-magnetic check-measure, this paper puts forward a new technology and method that use the magnetic marks to check and measure the dynamic physical parameters such as angle speed, ...Based on the principle of the electric-magnetic check-measure, this paper puts forward a new technology and method that use the magnetic marks to check and measure the dynamic physical parameters such as angle speed, bending strain,stress and bending moment. The principles of the check-measure and the dealing and exchanging technology about signals have been demonstrated and the rotating components have been made up. The timely and quantitative check-measure of the dynamic physical parameters during the component in working has been realized by using computer control.展开更多
The rapid changing near source, multi-stream depositional environment of conglomerate reservoirs leads to severe heterogeneity, complex lithology and physical properties, and large changes of oil layer resistivity. Qu...The rapid changing near source, multi-stream depositional environment of conglomerate reservoirs leads to severe heterogeneity, complex lithology and physical properties, and large changes of oil layer resistivity. Quantitative evaluation of water-flooded layers has become an important but difficult focus for secondary development of oilfields. In this paper, based on the analysis of current problems in quantitative evaluation of water-flooded layers, the Kexia Group conglomerate reservoir of the Sixth District in the Karamay Oilfield was studied. Eight types of conglomerate reservoir lithology were identified effectively by a data mining method combined with the data from sealed coring wells, and then a multi-parameter model for quantitative evaluation of the water-flooded layers of the main oil-bearing lithology was developed. Water production rate, oil saturation and oil productivity index were selected as the characteristic parameters for quantitative evaluation of water-flooded layers of conglomerate reservoirs. Finally, quantitative evaluation criteria and identification rules for water-flooded layers of main oil-bearing lithology formed by integration of the three characteristic parameters of water-flooded layer and undisturbed formation resistivity. This method has been used in evaluation of the water-flooded layers of a conglomerate reservoir in the Karamay Oilfield and achieved good results, improving the interpretation accuracy and compliance rate. It will provide technical support for avoiding perforation of high water-bearing layers and for adjustment of developmental programs.展开更多
Laser Induced Breakdown Spectroscopic(LIBS)technique was used to detect calcium and silicon in an unknown sample.In this method plasma was generated by Nd∶YAG laser of wavelength 1 064 nm with energy 400 mJ and pulse...Laser Induced Breakdown Spectroscopic(LIBS)technique was used to detect calcium and silicon in an unknown sample.In this method plasma was generated by Nd∶YAG laser of wavelength 1 064 nm with energy 400 mJ and pulse duration between 5~10ns.The method was applied for the qualitative as well as quantitative analysis.In the qualitative analysis,the electron number density(Ne)of plasma containing calcium and silicon is determined showing that Neof neutral particles is equivalent to 1016(cm-3)whereas for ionized particles it is 1017(cm-3).Plasma temperature is measured using Boltzmann plot method which must be greater than 10 000 k.Intensity ratio method is used for the quantitative analysis shows various elements in abundance with calcium and silicon in majority.展开更多
Maize(Zea mays L.) stands prominently as one of the major cereal crops in China as well as in the rest of the world.Therefore,predicting the growth and yield of maize for large areas through yield components under hig...Maize(Zea mays L.) stands prominently as one of the major cereal crops in China as well as in the rest of the world.Therefore,predicting the growth and yield of maize for large areas through yield components under high-yielding environments will help in understanding the process of yield formation and yield potential under different environmental conditions.This accurate early assessment of yield requires accuracy in the formation process of yield components as well.In order to formulate the quantitative design for high yields of maize in China,yield performance parameters of quantitative design for high grain yields were evaluated in this study,by utilizing the yield performance equation with normalization of planting density.Planting density was evaluated by parameters including the maximum leaf area index and the maximum leaf area per plant.Results showed that the variation of the maximum leaf area per plant with varying plant density conformed to the Reciprocal Model,which proved to have excellent prediction with root mean square error(RMSE) value of 5.95%.Yield model estimation depicted that the best optimal maximum leaf area per plant was 0.63 times the potential maximum leaf area per plant of hybrids.Yield performance parameters for different yield levels were quantitatively designed based on the yield performance equation.Through validation of the yield performance model by simulating high yields of spring maize in the Inner Mongolia Autonomous Region and Jilin Province,China,and summer maize in Shandong Province,the yield performance equation showed excellent prediction with the satisfactory mean RMSE value(7.72%) of all the parameters.The present study provides theoretical support for the formulation of quantitative design for sustainable high yield of maize in China,through consideration of planting density normalization in the yield prediction process,providing there is no water and nutrient limitation.展开更多
Objective:A high rate of unnecessary thymectomies has been reported.This study aimed to distinguish primary mediastinal lymphomas(PMLs)from thymic epithelial tumors(TETs)by evaluating volumetric and metabolic paramete...Objective:A high rate of unnecessary thymectomies has been reported.This study aimed to distinguish primary mediastinal lymphomas(PMLs)from thymic epithelial tumors(TETs)by evaluating volumetric and metabolic parameters with l8F-FDG PET/CT.Methods:A total of 136 patients who were pathologically diagnosed with TETs or PMLs were enrolled,and 18F-FDG PET/CT was performed before therapy.Volumetric parameters,including the mean SUV(SUVmean),metabolic tumor volume(MTV),total lesion glycolysis(TLG),and SUVmax,were determined and compared between the 2 subtypes.The diagnostic performance of these parameters was evaluated with receiver operating characteristic(ROC)curve analysis.Results:All parameters significantly differed between patients with PMLs and TETs.Patients with lymphomas were younger and had higher SUVmean,SUVmax,TLG,and MTV values than patients with TETs.The MTV and TLG values had similar diagnostic performance.ROC analysis indicated that the areas under the curves of the SUVmean and SUVmax values performed similarly(approximately 0.76)in differentiating patients with PMLs from TETs,and both values were better than the MTV and TLG values.When age was included with the SUVmax in differentiating TETs from PMLs,the AUC was 0.91,and the sensitivity and specificity increased to 80%and 93%,respectively.Conclusions:The SUVmax and volumetric parameters of 18F-FDG PET/CT can be used to distinguish patients with PMLs versus TETs,and thus may aid in preventing unnecessary thymectomies or other invasive operations.展开更多
Radar leveling system is the key equipment for improving the radar mobility and survival capability. A combined quantitative feedback theory (QFT) controller is designed for the radar truck leveling simulator in this ...Radar leveling system is the key equipment for improving the radar mobility and survival capability. A combined quantitative feedback theory (QFT) controller is designed for the radar truck leveling simulator in this paper, which suffers from strong nonlinearities and system parameter uncertainties. QFT can reduce the plant uncertainties and stabilize the system, but it fails to obtain high-precision tracking. This drawback can be solved by a robust QFT control scheme based on zero phase error tracking control (ZPETC) compensation. The combined controller not only possesses high robustness, but greatly improves the system performance. To verify the effiectiveness and the potential of the proposed controller, a series of experiments have been carried out. Experimental results have demonstrated its robustness against a large range of parameters variation and high tracking precision performance, as well as its capability of restraining the load coupling among channels. The combined QFT controller can drive the radar truck leveling platform accurately, quickly and stably.展开更多
By using computer imaging analysis system combined with light microscopy, the glomeruli lesions on biopsy specimens sections were quantitatively analysed. The patholoical changes of mesangial proliferative glomerulone...By using computer imaging analysis system combined with light microscopy, the glomeruli lesions on biopsy specimens sections were quantitatively analysed. The patholoical changes of mesangial proliferative glomerulonephritis (MsPGN) in children were quantitatively evaluated and the correlation between the mesangial matrix area (MA) and some clinical data were also analysed. The results indicated that the levels of various glomerular parameters in MsPGN group were higher than those of normal controls. No correlation was found between MA and 24 h urinary protein excretion, but a negative correlation was revealed between MA and estimated GFR. MA was also correlated with the duration of MsPGN recovery. It was suggested that the quantitative analysis of glomerular parameters by computer is a reproducible methods. The parameter of MA may be used for evaluation of the renal function, determination of the duration of therapy and evaluation of prognosis of MsPGN in children.展开更多
文摘BACKGROUND The level of Ki-67 expression has served as a prognostic factor in gastric cancer.The quantitative parameters based on the novel dual-layer spectral detector computed tomography(DLSDCT)in discriminating the Ki-67 expression status are unclear.AIM To investigate the diagnostic ability of DLSDCT-derived parameters for Ki-67 expression status in gastric carcinoma(GC).METHODS Dual-phase enhanced abdominal DLSDCT was performed preoperatively in 108 patients with gastric adenocarcinoma.Primary tumor monoenergetic CT attenuation value at 40-100 kilo electron volt(kev),the slope of the spectral curve(λ_(HU)),iodine concentration(IC),normalized IC(nIC),effective atomic number(Z^(eff))and normalized Z^(eff)(nZ^(eff))in the arterial phase(AP)and venous phase(VP)were retrospectively compared between patients with low and high Ki-67 expression in gastric adenocarcinoma.Spearman’s correlation coefficient was used to analyze the association between the above parameters and Ki-67 expression status.Receiver operating characteristic(ROC)curve analysis was performed to compare the diagnostic efficacy of the statistically significant parameters between two groups.RESULTS Thirty-seven and 71 patients were classified as having low and high Ki-67 expression,respectively.CT_(40 kev-VP),CT_(70 kev-VP),CT_(100 kev-VP),and Z^(eff)-related parameters were significantly higher,but IC-related parameters were lower in the group with low Ki-67 expression status than the group with high Ki-67 expression status,and other analyzed parameters showed no statistical difference between the two groups.Spearman’s correlation analysis showed that CT_(40 kev-VP),CT_(70 kev-VP),CT_(100 kev-VP),Z^(eff),and n Z^(eff) exhibited a negative correlation with Ki-67 status,whereas IC and nIC had positive correlation with Ki-67 status.The ROC analysis demonstrated that the multi-variable model of spectral parameters performed well in identifying the Ki-67 status[area under the curve(AUC)=0.967;sensitivity 95.77%;specificity 91.89%)].Nevertheless,the differentiating capabilities of singlevariable model were moderate(AUC value 0.630-0.835).In addition,the nZ_(VP)^(eff) and nIC_(VP)(AUC 0.835 and 0.805)showed better performance than CT_(40 kev-VP),CT_(70 kev-VP) and CT_(100 kev-VP)(AUC 0.630,0.631 and 0.662)in discriminating the Ki-67 status.CONCLUSION Quantitative spectral parameters are feasible to distinguish low and high Ki-67 expression in gastric adenocarcinoma.Z^(eff) and IC may be useful parameters for evaluating the Ki-67 expression.
文摘The statistical probability and their variation regularity of the measurable characteristic parameters in the CO 2 arc welding droplet short circuiting transfer process have been studied. The statistical analysis shows that the sensitivity of each characteristic parameter with regard to the variation of the short circuiting transfer process is different. The sensitivity of 4 kinds among these characteristic parameters is more intense than that of the short circuiting transfer frequency. In order to take account of the synthetic influence of these characteristic parameters, by means of the characteristic parameters synthetic value, a quantitative evaluation function is built up to describe and evaluate the short circuiting transfer process of CO 2 arc welding in real time. The testing shows that the evaluation function can give a suitable synthetic valuation for the short circuiting transfer process with a variety of welding variables.
基金Projects(51474251,51874351)supported by the National Natural Science Foundation,China。
文摘It is important to calibrate micro-parameters for applying partied flow code(PFC)to study mechanical characteristics and failure mechanism of rock materials.Uniform design method is firstly adopted to determine the microscopic parameters of parallel-bonded particle model for three-dimensional discrete element particle flow code(PFC3D).Variation ranges of microscopic of the microscopic parameters are created by analyzing the effects of microscopic parameters on macroscopic parameters(elastic modulus E,Poisson ratio v,uniaxial compressive strengthσc,and ratio of crack initial stress to uniaxial compressive strengthσci/σc)in order to obtain the actual uniform design talbe.The calculation equations of the microscopic and macroscopic parameters of rock materials can be established by the actual uniform design table and the regression analysis and thus the PFC3D microscopic parameters can be quantitatively determined.The PFC3D simulated results of the intact and pre-cracked rock specimens under uniaxial and triaxial compressions(including the macroscopic mechanical parameters,stress−strain curves and failure process)are in good agreement with experimental results,which can prove the validity of the calculation equations of microscopic and macroscopic parameters.
文摘Our expedition have identified location in the central part of Kosovo where were collected a samples （accessions） at coordinates; Sub-Locality SL-1 （N42°34′36″, E21°07′45″）, altitude 574 m, SL-2 （N42°34′29″, E 21°07′45″altitude 591 m and SL-3 （N42°34′30″, E21°07′46″） on altitude 565 m. The aim of present investigation was carried out to study genetic variability of quantitative and qualitative parameters. The populations from SL-2 were characterized of higher significance on seed oil （23.74%） and protein content （16.74%）. The estimation average value of seed protein and oil content was 15.52% and 23.48% respectively. The variability of plant height ranged from 182.33 cm to as much as 200.89 cm, while distinction＇s between them were ＋ 18.56 cm which was a significant higher at P〈0.05 probability level. The SL-3 showed the higher value of HWK （34.6 g）, head per plant （39.33） and head diameter （9.5 cm） but, was characterized significantly lowest on seed protein content （13.99%）. The all traits included in our investigations showed a higher genetic variability with majority of extreme values. The sunflower populations differed significantly in several parameters measured, they have a different genetic and morphological backgrounds. Results from wild sunflower form indicated notable differences in dispersion of important genes for different traits and showed the potential for using in future for breeding program.
文摘Based on the principle of the electric-magnetic check-measure, this paper puts forward a new technology and method that use the magnetic marks to check and measure the dynamic physical parameters such as angle speed, bending strain,stress and bending moment. The principles of the check-measure and the dealing and exchanging technology about signals have been demonstrated and the rotating components have been made up. The timely and quantitative check-measure of the dynamic physical parameters during the component in working has been realized by using computer control.
文摘The rapid changing near source, multi-stream depositional environment of conglomerate reservoirs leads to severe heterogeneity, complex lithology and physical properties, and large changes of oil layer resistivity. Quantitative evaluation of water-flooded layers has become an important but difficult focus for secondary development of oilfields. In this paper, based on the analysis of current problems in quantitative evaluation of water-flooded layers, the Kexia Group conglomerate reservoir of the Sixth District in the Karamay Oilfield was studied. Eight types of conglomerate reservoir lithology were identified effectively by a data mining method combined with the data from sealed coring wells, and then a multi-parameter model for quantitative evaluation of the water-flooded layers of the main oil-bearing lithology was developed. Water production rate, oil saturation and oil productivity index were selected as the characteristic parameters for quantitative evaluation of water-flooded layers of conglomerate reservoirs. Finally, quantitative evaluation criteria and identification rules for water-flooded layers of main oil-bearing lithology formed by integration of the three characteristic parameters of water-flooded layer and undisturbed formation resistivity. This method has been used in evaluation of the water-flooded layers of a conglomerate reservoir in the Karamay Oilfield and achieved good results, improving the interpretation accuracy and compliance rate. It will provide technical support for avoiding perforation of high water-bearing layers and for adjustment of developmental programs.
文摘Laser Induced Breakdown Spectroscopic(LIBS)technique was used to detect calcium and silicon in an unknown sample.In this method plasma was generated by Nd∶YAG laser of wavelength 1 064 nm with energy 400 mJ and pulse duration between 5~10ns.The method was applied for the qualitative as well as quantitative analysis.In the qualitative analysis,the electron number density(Ne)of plasma containing calcium and silicon is determined showing that Neof neutral particles is equivalent to 1016(cm-3)whereas for ionized particles it is 1017(cm-3).Plasma temperature is measured using Boltzmann plot method which must be greater than 10 000 k.Intensity ratio method is used for the quantitative analysis shows various elements in abundance with calcium and silicon in majority.
基金supported by the National Key Research and Development Program of China(2018YFD020060 and 2017YFD0301307)the National Natural Science Foundation of China(31971851)the earmarked fund for China Agriculture Research System(CARS-02-12)
文摘Maize(Zea mays L.) stands prominently as one of the major cereal crops in China as well as in the rest of the world.Therefore,predicting the growth and yield of maize for large areas through yield components under high-yielding environments will help in understanding the process of yield formation and yield potential under different environmental conditions.This accurate early assessment of yield requires accuracy in the formation process of yield components as well.In order to formulate the quantitative design for high yields of maize in China,yield performance parameters of quantitative design for high grain yields were evaluated in this study,by utilizing the yield performance equation with normalization of planting density.Planting density was evaluated by parameters including the maximum leaf area index and the maximum leaf area per plant.Results showed that the variation of the maximum leaf area per plant with varying plant density conformed to the Reciprocal Model,which proved to have excellent prediction with root mean square error(RMSE) value of 5.95%.Yield model estimation depicted that the best optimal maximum leaf area per plant was 0.63 times the potential maximum leaf area per plant of hybrids.Yield performance parameters for different yield levels were quantitatively designed based on the yield performance equation.Through validation of the yield performance model by simulating high yields of spring maize in the Inner Mongolia Autonomous Region and Jilin Province,China,and summer maize in Shandong Province,the yield performance equation showed excellent prediction with the satisfactory mean RMSE value(7.72%) of all the parameters.The present study provides theoretical support for the formulation of quantitative design for sustainable high yield of maize in China,through consideration of planting density normalization in the yield prediction process,providing there is no water and nutrient limitation.
基金the Tianjin Science and Technology Program Fund(grant No.18 PTZWHZ00100 and H2018206600).
文摘Objective:A high rate of unnecessary thymectomies has been reported.This study aimed to distinguish primary mediastinal lymphomas(PMLs)from thymic epithelial tumors(TETs)by evaluating volumetric and metabolic parameters with l8F-FDG PET/CT.Methods:A total of 136 patients who were pathologically diagnosed with TETs or PMLs were enrolled,and 18F-FDG PET/CT was performed before therapy.Volumetric parameters,including the mean SUV(SUVmean),metabolic tumor volume(MTV),total lesion glycolysis(TLG),and SUVmax,were determined and compared between the 2 subtypes.The diagnostic performance of these parameters was evaluated with receiver operating characteristic(ROC)curve analysis.Results:All parameters significantly differed between patients with PMLs and TETs.Patients with lymphomas were younger and had higher SUVmean,SUVmax,TLG,and MTV values than patients with TETs.The MTV and TLG values had similar diagnostic performance.ROC analysis indicated that the areas under the curves of the SUVmean and SUVmax values performed similarly(approximately 0.76)in differentiating patients with PMLs from TETs,and both values were better than the MTV and TLG values.When age was included with the SUVmax in differentiating TETs from PMLs,the AUC was 0.91,and the sensitivity and specificity increased to 80%and 93%,respectively.Conclusions:The SUVmax and volumetric parameters of 18F-FDG PET/CT can be used to distinguish patients with PMLs versus TETs,and thus may aid in preventing unnecessary thymectomies or other invasive operations.
文摘Radar leveling system is the key equipment for improving the radar mobility and survival capability. A combined quantitative feedback theory (QFT) controller is designed for the radar truck leveling simulator in this paper, which suffers from strong nonlinearities and system parameter uncertainties. QFT can reduce the plant uncertainties and stabilize the system, but it fails to obtain high-precision tracking. This drawback can be solved by a robust QFT control scheme based on zero phase error tracking control (ZPETC) compensation. The combined controller not only possesses high robustness, but greatly improves the system performance. To verify the effiectiveness and the potential of the proposed controller, a series of experiments have been carried out. Experimental results have demonstrated its robustness against a large range of parameters variation and high tracking precision performance, as well as its capability of restraining the load coupling among channels. The combined QFT controller can drive the radar truck leveling platform accurately, quickly and stably.
文摘By using computer imaging analysis system combined with light microscopy, the glomeruli lesions on biopsy specimens sections were quantitatively analysed. The patholoical changes of mesangial proliferative glomerulonephritis (MsPGN) in children were quantitatively evaluated and the correlation between the mesangial matrix area (MA) and some clinical data were also analysed. The results indicated that the levels of various glomerular parameters in MsPGN group were higher than those of normal controls. No correlation was found between MA and 24 h urinary protein excretion, but a negative correlation was revealed between MA and estimated GFR. MA was also correlated with the duration of MsPGN recovery. It was suggested that the quantitative analysis of glomerular parameters by computer is a reproducible methods. The parameter of MA may be used for evaluation of the renal function, determination of the duration of therapy and evaluation of prognosis of MsPGN in children.
