In order to improve the performance of the traditional hybrid time-of-arrival(TOA)/angle-of-arrival(AOA)location algorithm in non-line-of-sight(NLOS)environments,a new hybrid TOA/AOA location estimation algorith...In order to improve the performance of the traditional hybrid time-of-arrival(TOA)/angle-of-arrival(AOA)location algorithm in non-line-of-sight(NLOS)environments,a new hybrid TOA/AOA location estimation algorithm by utilizing scatterer information is proposed.The linearized region of the mobile station(MS)is obtained according to the base station(BS)coordinates and the TOA measurements.The candidate points(CPs)of the MS are generated from this region.Then,using the measured TOA and AOA measurements,the radius of each scatterer is computed.Compared with the prior scatterer information,true CPs are obtained among all the CPs.The adaptive fuzzy clustering(AFC)technology is adopted to estimate the position of the MS with true CPs.Finally,simulations are conducted to evaluate the performance of the algorithm.The results demonstrate that the proposed location algorithm can significantly mitigate the NLOS effect and efficiently estimate the MS position.展开更多
In this study, the water budget in the treatment of high salinity landfill-leachate was estimated and the influence of evapotranspiration (ET) on treatment performance was investigated. The salinity of the inside of...In this study, the water budget in the treatment of high salinity landfill-leachate was estimated and the influence of evapotranspiration (ET) on treatment performance was investigated. The salinity of the inside of horizontal subsurface flow constructed wetland (HSF) of the raw leachate inflow was 15.0± 3.4 g.Cl/L which was in the level of the salinity of the survival limit of reed, and that of the double diluted leachate inflow was 9.3 ± 1.9 g.CI7L. There were large differences in the vegetation between HSF of the raw leachate inflow and that of the double diluted leachate inflow. The dense vegetation bed of double diluted leachate inflow during the growing season (April-October) provided a high ET and a large water loss, which made great contributions to the reduction of the outflow load of COD and T-N. The HSF with die-back reeds in the non-growing season (November-March) provided a slight ET and a small water loss and made less of a contribution to pollutant removal compared to the HSF with dense vegetation bed during the growing season. However, the HSF with die-back reeds during the non-growing season exhibited higher removal performance than the unplanted HSF.展开更多
The diagnosis of cystadenoma is rare, even more so when located in the extrahepatic bile duct. Unspecific clinical signs may lead this pathology to be misdiagnosed. The need for pathological anatomy in order to distin...The diagnosis of cystadenoma is rare, even more so when located in the extrahepatic bile duct. Unspecific clinical signs may lead this pathology to be misdiagnosed. The need for pathological anatomy in order to distinguish cystadenomas from simple biliary cysts is crucial. The most usual treatment nowadays is resection of the bile duct, together with cholecystectomy and Roux-en-Y reconstruction.展开更多
AIM To investigate the diagnostic performance of liver stiffness measurement(LSM) by elastography point quantification(Elast PQ) in animal models and determine the longitudinal changes in liver stiffness by Elast PQ a...AIM To investigate the diagnostic performance of liver stiffness measurement(LSM) by elastography point quantification(Elast PQ) in animal models and determine the longitudinal changes in liver stiffness by Elast PQ after splenectomy at different stages of fibrosis.METHODS Liver stiffness was measured in sixty-eight rabbits with CCl4-induced liver fibrosis at different stages and eight healthy control rabbits by Elast PQ. Liver biopsies and blood samples were obtained at scheduled time points to assess liver function and degree of fibrosis. Thirty-one rabbits with complete data that underwent splenectomy at different stages of liver fibrosis were then included for dynamic monitoring of changes in liver stiffness by Elast PQ and liver function according to blood tests.RESULTS LSM by Elast PQ was significantly correlated with histologic fibrosis stage(r = 0.85, P < 0.001). The optimal cutoff values by Elast PQ were 11.27, 14.89, and 18.21 k Pa for predicting minimal fibrosis, moderate fibrosis, and cirrhosis, respectively. Longitudinalmonitoring of the changes in liver stiffness by Elast PQ showed that early splenectomy(especially F1) may delay liver fibrosis progression.CONCLUSION Elast PQ is an available, convenient, objective and non-invasive technique for assessing liver stiffness in rabbits with CCl4-induced liver fibrosis. In addition, liver stiffness measurements using Elast PQ can dynamically monitor the changes in liver stiffness in rabbit models, and in patients, after splenectomy.展开更多
Several reports have described an apparently uncommon clinicopathological disorder that is characterized by multifocal stenosing small-intestinal ulceration.Compared to Crohn's disease,the ulcers are not transmura...Several reports have described an apparently uncommon clinicopathological disorder that is characterized by multifocal stenosing small-intestinal ulceration.Compared to Crohn's disease,the ulcers are not transmural and typically remain shallow,and involve only the mucosa and submucosa.The disorder seems to be localized in the jejunum and proximal ileum only,and not the distal ileum or colon.Only nonspecif ic inflammatory changes are present without giant cells or other typical features of granulomatous inflammation.Most patients present clinically with recurrent obstructive events that usually respond to steroids,surgical resection,or both.With the development of newer imaging modalities to visualize the small-intestinal mucosa,such as double-balloon enteroscopy,improved understanding of the long-term natural history of this apparently distinctive disorder should emerge.展开更多
The carbon dioxide removal system is the most critical system for controlling CO2 mass concentration in long-term manned spacecraft.In order to ensure the controlling CO2 mass concentration in the cabin within the all...The carbon dioxide removal system is the most critical system for controlling CO2 mass concentration in long-term manned spacecraft.In order to ensure the controlling CO2 mass concentration in the cabin within the allowable range,the state of CO2 removal system needs to be estimated in real time.In this paper,the mathematical model is firstly established that describes the actual system conditions and then the Galerkin-based extended Kalman filter algorithm is proposed for the estimation of the state of CO2.This method transforms partial differential equation to ordinary differential equation by using Galerkin approaching method,and then carries out the state estimation by using extended Kalman filter.Simulation experiments were performed with the qualification of the actual manned space mission.The simulation results show that the proposed method can effectively estimate the system state while avoiding the problem of dimensional explosion,and has strong robustness regarding measurement noise.Thus,this method can establish a basis for system fault diagnosis and fault positioning.展开更多
Objective: To evaluate the short-term outcomes of video-assisted thoracic surgery (VATS) for thoracic tumors. Methods: The data of 1,790 consecutive patients were retrospectively reviewed. These patients underwent...Objective: To evaluate the short-term outcomes of video-assisted thoracic surgery (VATS) for thoracic tumors. Methods: The data of 1,790 consecutive patients were retrospectively reviewed. These patients underwent VATS pulmonary resections, VATS esophagectomies, and VATS resections of mediastinal tumors or biopsies at the Cancer Institute & Hospital, Chinese Academy of Medical Sciences between January 2009 and January 2012. Results: There were 33 patients converted to open thoracotomy (OT, 1.84%). The overall morbidity and mortality rate was 2.79% (50/1790) and 0.28% (5/1790), respectively. The overall hospitalization and chest tube duration were shorter in the VATS lobectomy group (n=949) than in the open thoracotomy (OT) lobectomy group (n=753). There were no significant differences in morbidity rate, mortality rate and operation time between the two groups. In the esophageal cancer patients, no significant difference was found in the number of nodal dissection, chest tube duration, morbidity rate, mortality rate, and hospital length of stay between the VATS esophagectomy group (n=8 1) and open esophagectomy group (n=81). However, the operation time was longer in the VATS esophagectomy group. In the thymoma patients, there was no significant difference in the chest tube duration, morbidity rate, mortality rate, and hospital length of stay between the VATS thymectomy group (n=41) and open thymectomy group (n=41). However, the operation time was longer in the VATS group. The median tumor size in the VATS thymectomy group was comparable with that in the OT group. Conclusions: In early-stage (Ⅰ/Ⅱ) non-small cell lung cancer patients who underwent lobectomies, VATS is comparable with the OT approach with similar short-term outcomes. In patients with resectable esophageal cancer, VATS esophagectomy is comparable with OT esophagectomy with similar morbidity and mortality. VATS thymectomy for Masaoka stage I and II thymoma is feasible and safe, and tumor size is not contraindicated. Longer follow-ups are needed to determine the oncologic equivalency of VATS lobectomy, esophagectomy, and thymectomy for thymoma vs. OT.展开更多
Objective: To evaluate the safety, efficacy, feasibility of single-direction thoracoscopic lobectomy for peripheral lung cancer. Methods: From December 2009 to March 2011, 20 patients with peripheral lung cancer were ...Objective: To evaluate the safety, efficacy, feasibility of single-direction thoracoscopic lobectomy for peripheral lung cancer. Methods: From December 2009 to March 2011, 20 patients with peripheral lung cancer were treated with single-direction thoracoscopic lobectomy and systemic lymph nodes dissection. Results: Surgeries were successfully performed. No significant complications occurred perioperatively. The average operation time was 193 min, the average blood loss was 234 ml, the average duration of drainage was 6 d, the postoperative hospital stay was 12 d, and the average number of lymph nodes dissected was 16. Conclusion: Single-direction thoracoscopic lobectomy is feasible and safe in the treatment of peripheral lung cancer and can simplify the surgical procedures.展开更多
An excess of reactive oxygen species(ROS)leads to a variety of chronic health problems.As potent antioxidants,marine bioactive extracts containing oligosaccharides and peptides have been extensively studied.Recently...An excess of reactive oxygen species(ROS)leads to a variety of chronic health problems.As potent antioxidants,marine bioactive extracts containing oligosaccharides and peptides have been extensively studied.Recently,there is a growing interest in protein-polysaccharide complexes because of their potential uses in pharmaceutical and food industries.However,only few studies are available on the antioxidant activities of such complexes,in terms of their ROS scavenging capability.In this study,we combined and superoxide radicals,and to evaluate the influences on the activities of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px)and the level of malondialdehyde(MDA)in UV-induced photoaging models.The results indicated that the antioxidant activities of all the complexes were stronger than those of their individual components.Among the 11 complexes tested,two complexes,namely MA1000+CP and κ-ca3000+CP,turned out to be highly effective antioxidants.Although the detailed mechanisms of this improved scavenging ability are not fully understood,this work provides insights into the design of highly efficient peptide-oligosaccharide complexes for potential applications in pharmaceutical,cosmetics and food industries.展开更多
Glufosinate-ammonium is a highly efficient, non-selective herbicide. The former synthesis schemes of glufosinate-ammonium were introduced and analyzed, the main of which are Arbuzov synthesis method, method under cata...Glufosinate-ammonium is a highly efficient, non-selective herbicide. The former synthesis schemes of glufosinate-ammonium were introduced and analyzed, the main of which are Arbuzov synthesis method, method under catalyzer and high pressure, targeted method under low temperature, Gabriel synthesis method, Zelinsky-Strecher synthetic method, synthetic method with chiral-synthon, and several special methods such as with enzyme or stereochemistry. Based on the structure and synthesis characteristic of glufosinate-ammonium as well as Arbuzov reaction and Michael reaction, a novel and reasonable scheme, which was named Arbuzov-Michael method, was put forward as the more economical one with simpler raw reagents and less waste.展开更多
In MIMO full duplex system,power amplifier(PA) nonlinearity limits the self-interference(SI) cancellation seriously. Most existing methods need to model and estimate the PA nonlinearity in order to reconstruct the SI,...In MIMO full duplex system,power amplifier(PA) nonlinearity limits the self-interference(SI) cancellation seriously. Most existing methods need to model and estimate the PA nonlinearity in order to reconstruct the SI,however the estimation error caused by the mismatch between the estimated PA model and the actual PA property still impacts the cancellation ability,especially when the transmit power is high. In this paper we propose a polarization oblique projection based self-interference cancellation method which does not need to estimate the PA nonlinearity coefficients. It exploits the polarization state information of the signals which is immune to the PA nonlinearity,and establishes an oblique projection operator to cancel the SI. Numerical results and analysis demonstrate that it can cancel the nonlinear SI effectively. Moreover the signal to interfere plus noise ratio(SINR) and the achievable sum rate do not deteriorate when the transmit power is high. Further,the upper bound of the achievable sum rate can be more than twice that of the half duplex.展开更多
Particulate emission is a major problem in industrial processes, mainly power plants that make use of coal as a primary source of energy. Stringent emissions limits, set by government organisations requires industries...Particulate emission is a major problem in industrial processes, mainly power plants that make use of coal as a primary source of energy. Stringent emissions limits, set by government organisations requires industries to conform to these limits to ensure that air quality is sustained and with minimum pollutant present. Electrostatic precipitators are typically used to filter and collect these particulate emissions. Fly ash resistivity is a primary parameter in the collection of particulate emissions, and there is a resistivity range at which electrostatic precipitator collection is most efficient and anything outside this range limits, their operation. High resistivity ash results in back-corona discharge, whilst low resistivity results in particle re-entrainment into the flue gas stream. The purpose of this paper is to investigate and obtain a fly ash resistivity profile for existing power plants in South Africa. Ash samples obtained from power plants are, tested making use of an ash-resistivity test oven, in accordance with IEEE Standard 548-1984. This paper discusses obtained experimental results, to determine the resistivity profile at which South African power plant electrostatic precipitators operate. The electrical efficiency of the electrostatic precipitator system is evaluated based on the obtained resistivity profiles.展开更多
A non invasive ultrasonic method is used to detect whether or not the frozen fish has suffered a partial or total accidental thawing. The time of flight and the peak to peak amplitude of the ultrasonic signals backsca...A non invasive ultrasonic method is used to detect whether or not the frozen fish has suffered a partial or total accidental thawing. The time of flight and the peak to peak amplitude of the ultrasonic signals backscattered by fish are recorded during thawing. The comparison of the evolution curves and images corresponding to first and second thawing shows indicators of accidental thawing. The monitoring of thawing process showed that its assessment can be reduced to the measurement of the water content lost by fish. The attempt to replace the original water lost by fish in first thawing is analyzed. The influence of the transducer frequency on fish thawing evaluation is tested.展开更多
Objective: The aim of the study was to identify prognostic factors in non-small-cell lung cancer (NSCLC) with N2 nodal involvement.Methods: A retrospective analysis of disease free survival and 5-year survival for NSC...Objective: The aim of the study was to identify prognostic factors in non-small-cell lung cancer (NSCLC) with N2 nodal involvement.Methods: A retrospective analysis of disease free survival and 5-year survival for NSCLC patients who underwent primary surgical resection without neoadjuvant chemotherapy were performed.Between January 1998 and May 2004,133 patients were enrolled.Several factors such as age,sex,skip metastasis,number of N2 lymph node stations,type of resection,histology,adjuvant therapy etc.,were recorded and analyzed.SPSS 16.0 software was used.Results: Overall 5-year survival for 133 patients was 32.33%,5-year survival for single N2 station and multiple N2 stations sub-groups were 39.62% and 27.50% respectively,and 5-year survival for cN0–1 and cN2 sub-groups were 37.78% and 20.93% respectively.COX regression analysis revealed that number of N2 station (P = 0.013,OR: 0.490,95% CI: 0.427–0.781) and cN status (P = 0.009,OR: 0.607,95% CI: 0.372–0.992) were two favorable prognostic factors of survival.Conclusion: Number of N2 station and cN status were two favorable prognostic factors of survival.In restrict enrolled circumstances,after combined therapy made up of surgery and postoperative adjuvant therapy have been performed,satisfied survival could be achieved.展开更多
基金The National High Technology Research and Development Program of China(863Program)(No.2008AA01Z227)the National Natural Science Foundation of China(No.60872075)
文摘In order to improve the performance of the traditional hybrid time-of-arrival(TOA)/angle-of-arrival(AOA)location algorithm in non-line-of-sight(NLOS)environments,a new hybrid TOA/AOA location estimation algorithm by utilizing scatterer information is proposed.The linearized region of the mobile station(MS)is obtained according to the base station(BS)coordinates and the TOA measurements.The candidate points(CPs)of the MS are generated from this region.Then,using the measured TOA and AOA measurements,the radius of each scatterer is computed.Compared with the prior scatterer information,true CPs are obtained among all the CPs.The adaptive fuzzy clustering(AFC)technology is adopted to estimate the position of the MS with true CPs.Finally,simulations are conducted to evaluate the performance of the algorithm.The results demonstrate that the proposed location algorithm can significantly mitigate the NLOS effect and efficiently estimate the MS position.
文摘In this study, the water budget in the treatment of high salinity landfill-leachate was estimated and the influence of evapotranspiration (ET) on treatment performance was investigated. The salinity of the inside of horizontal subsurface flow constructed wetland (HSF) of the raw leachate inflow was 15.0± 3.4 g.Cl/L which was in the level of the salinity of the survival limit of reed, and that of the double diluted leachate inflow was 9.3 ± 1.9 g.CI7L. There were large differences in the vegetation between HSF of the raw leachate inflow and that of the double diluted leachate inflow. The dense vegetation bed of double diluted leachate inflow during the growing season (April-October) provided a high ET and a large water loss, which made great contributions to the reduction of the outflow load of COD and T-N. The HSF with die-back reeds in the non-growing season (November-March) provided a slight ET and a small water loss and made less of a contribution to pollutant removal compared to the HSF with dense vegetation bed during the growing season. However, the HSF with die-back reeds during the non-growing season exhibited higher removal performance than the unplanted HSF.
文摘The diagnosis of cystadenoma is rare, even more so when located in the extrahepatic bile duct. Unspecific clinical signs may lead this pathology to be misdiagnosed. The need for pathological anatomy in order to distinguish cystadenomas from simple biliary cysts is crucial. The most usual treatment nowadays is resection of the bile duct, together with cholecystectomy and Roux-en-Y reconstruction.
文摘AIM To investigate the diagnostic performance of liver stiffness measurement(LSM) by elastography point quantification(Elast PQ) in animal models and determine the longitudinal changes in liver stiffness by Elast PQ after splenectomy at different stages of fibrosis.METHODS Liver stiffness was measured in sixty-eight rabbits with CCl4-induced liver fibrosis at different stages and eight healthy control rabbits by Elast PQ. Liver biopsies and blood samples were obtained at scheduled time points to assess liver function and degree of fibrosis. Thirty-one rabbits with complete data that underwent splenectomy at different stages of liver fibrosis were then included for dynamic monitoring of changes in liver stiffness by Elast PQ and liver function according to blood tests.RESULTS LSM by Elast PQ was significantly correlated with histologic fibrosis stage(r = 0.85, P < 0.001). The optimal cutoff values by Elast PQ were 11.27, 14.89, and 18.21 k Pa for predicting minimal fibrosis, moderate fibrosis, and cirrhosis, respectively. Longitudinalmonitoring of the changes in liver stiffness by Elast PQ showed that early splenectomy(especially F1) may delay liver fibrosis progression.CONCLUSION Elast PQ is an available, convenient, objective and non-invasive technique for assessing liver stiffness in rabbits with CCl4-induced liver fibrosis. In addition, liver stiffness measurements using Elast PQ can dynamically monitor the changes in liver stiffness in rabbit models, and in patients, after splenectomy.
文摘Several reports have described an apparently uncommon clinicopathological disorder that is characterized by multifocal stenosing small-intestinal ulceration.Compared to Crohn's disease,the ulcers are not transmural and typically remain shallow,and involve only the mucosa and submucosa.The disorder seems to be localized in the jejunum and proximal ileum only,and not the distal ileum or colon.Only nonspecif ic inflammatory changes are present without giant cells or other typical features of granulomatous inflammation.Most patients present clinically with recurrent obstructive events that usually respond to steroids,surgical resection,or both.With the development of newer imaging modalities to visualize the small-intestinal mucosa,such as double-balloon enteroscopy,improved understanding of the long-term natural history of this apparently distinctive disorder should emerge.
基金Project(050403)supported by Pre-research Project in the Manned Space Filed of China。
文摘The carbon dioxide removal system is the most critical system for controlling CO2 mass concentration in long-term manned spacecraft.In order to ensure the controlling CO2 mass concentration in the cabin within the allowable range,the state of CO2 removal system needs to be estimated in real time.In this paper,the mathematical model is firstly established that describes the actual system conditions and then the Galerkin-based extended Kalman filter algorithm is proposed for the estimation of the state of CO2.This method transforms partial differential equation to ordinary differential equation by using Galerkin approaching method,and then carries out the state estimation by using extended Kalman filter.Simulation experiments were performed with the qualification of the actual manned space mission.The simulation results show that the proposed method can effectively estimate the system state while avoiding the problem of dimensional explosion,and has strong robustness regarding measurement noise.Thus,this method can establish a basis for system fault diagnosis and fault positioning.
文摘Objective: To evaluate the short-term outcomes of video-assisted thoracic surgery (VATS) for thoracic tumors. Methods: The data of 1,790 consecutive patients were retrospectively reviewed. These patients underwent VATS pulmonary resections, VATS esophagectomies, and VATS resections of mediastinal tumors or biopsies at the Cancer Institute & Hospital, Chinese Academy of Medical Sciences between January 2009 and January 2012. Results: There were 33 patients converted to open thoracotomy (OT, 1.84%). The overall morbidity and mortality rate was 2.79% (50/1790) and 0.28% (5/1790), respectively. The overall hospitalization and chest tube duration were shorter in the VATS lobectomy group (n=949) than in the open thoracotomy (OT) lobectomy group (n=753). There were no significant differences in morbidity rate, mortality rate and operation time between the two groups. In the esophageal cancer patients, no significant difference was found in the number of nodal dissection, chest tube duration, morbidity rate, mortality rate, and hospital length of stay between the VATS esophagectomy group (n=8 1) and open esophagectomy group (n=81). However, the operation time was longer in the VATS esophagectomy group. In the thymoma patients, there was no significant difference in the chest tube duration, morbidity rate, mortality rate, and hospital length of stay between the VATS thymectomy group (n=41) and open thymectomy group (n=41). However, the operation time was longer in the VATS group. The median tumor size in the VATS thymectomy group was comparable with that in the OT group. Conclusions: In early-stage (Ⅰ/Ⅱ) non-small cell lung cancer patients who underwent lobectomies, VATS is comparable with the OT approach with similar short-term outcomes. In patients with resectable esophageal cancer, VATS esophagectomy is comparable with OT esophagectomy with similar morbidity and mortality. VATS thymectomy for Masaoka stage I and II thymoma is feasible and safe, and tumor size is not contraindicated. Longer follow-ups are needed to determine the oncologic equivalency of VATS lobectomy, esophagectomy, and thymectomy for thymoma vs. OT.
文摘Objective: To evaluate the safety, efficacy, feasibility of single-direction thoracoscopic lobectomy for peripheral lung cancer. Methods: From December 2009 to March 2011, 20 patients with peripheral lung cancer were treated with single-direction thoracoscopic lobectomy and systemic lymph nodes dissection. Results: Surgeries were successfully performed. No significant complications occurred perioperatively. The average operation time was 193 min, the average blood loss was 234 ml, the average duration of drainage was 6 d, the postoperative hospital stay was 12 d, and the average number of lymph nodes dissected was 16. Conclusion: Single-direction thoracoscopic lobectomy is feasible and safe in the treatment of peripheral lung cancer and can simplify the surgical procedures.
基金funded by the National High Technology Research and Development Program of China 863 Program Grant (2001AA620405)
文摘An excess of reactive oxygen species(ROS)leads to a variety of chronic health problems.As potent antioxidants,marine bioactive extracts containing oligosaccharides and peptides have been extensively studied.Recently,there is a growing interest in protein-polysaccharide complexes because of their potential uses in pharmaceutical and food industries.However,only few studies are available on the antioxidant activities of such complexes,in terms of their ROS scavenging capability.In this study,we combined and superoxide radicals,and to evaluate the influences on the activities of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px)and the level of malondialdehyde(MDA)in UV-induced photoaging models.The results indicated that the antioxidant activities of all the complexes were stronger than those of their individual components.Among the 11 complexes tested,two complexes,namely MA1000+CP and κ-ca3000+CP,turned out to be highly effective antioxidants.Although the detailed mechanisms of this improved scavenging ability are not fully understood,this work provides insights into the design of highly efficient peptide-oligosaccharide complexes for potential applications in pharmaceutical,cosmetics and food industries.
文摘Glufosinate-ammonium is a highly efficient, non-selective herbicide. The former synthesis schemes of glufosinate-ammonium were introduced and analyzed, the main of which are Arbuzov synthesis method, method under catalyzer and high pressure, targeted method under low temperature, Gabriel synthesis method, Zelinsky-Strecher synthetic method, synthetic method with chiral-synthon, and several special methods such as with enzyme or stereochemistry. Based on the structure and synthesis characteristic of glufosinate-ammonium as well as Arbuzov reaction and Michael reaction, a novel and reasonable scheme, which was named Arbuzov-Michael method, was put forward as the more economical one with simpler raw reagents and less waste.
基金supported by the National Natural Science Foundations of China under Grant No.61501050 and No.61271177
文摘In MIMO full duplex system,power amplifier(PA) nonlinearity limits the self-interference(SI) cancellation seriously. Most existing methods need to model and estimate the PA nonlinearity in order to reconstruct the SI,however the estimation error caused by the mismatch between the estimated PA model and the actual PA property still impacts the cancellation ability,especially when the transmit power is high. In this paper we propose a polarization oblique projection based self-interference cancellation method which does not need to estimate the PA nonlinearity coefficients. It exploits the polarization state information of the signals which is immune to the PA nonlinearity,and establishes an oblique projection operator to cancel the SI. Numerical results and analysis demonstrate that it can cancel the nonlinear SI effectively. Moreover the signal to interfere plus noise ratio(SINR) and the achievable sum rate do not deteriorate when the transmit power is high. Further,the upper bound of the achievable sum rate can be more than twice that of the half duplex.
文摘Particulate emission is a major problem in industrial processes, mainly power plants that make use of coal as a primary source of energy. Stringent emissions limits, set by government organisations requires industries to conform to these limits to ensure that air quality is sustained and with minimum pollutant present. Electrostatic precipitators are typically used to filter and collect these particulate emissions. Fly ash resistivity is a primary parameter in the collection of particulate emissions, and there is a resistivity range at which electrostatic precipitator collection is most efficient and anything outside this range limits, their operation. High resistivity ash results in back-corona discharge, whilst low resistivity results in particle re-entrainment into the flue gas stream. The purpose of this paper is to investigate and obtain a fly ash resistivity profile for existing power plants in South Africa. Ash samples obtained from power plants are, tested making use of an ash-resistivity test oven, in accordance with IEEE Standard 548-1984. This paper discusses obtained experimental results, to determine the resistivity profile at which South African power plant electrostatic precipitators operate. The electrical efficiency of the electrostatic precipitator system is evaluated based on the obtained resistivity profiles.
文摘A non invasive ultrasonic method is used to detect whether or not the frozen fish has suffered a partial or total accidental thawing. The time of flight and the peak to peak amplitude of the ultrasonic signals backscattered by fish are recorded during thawing. The comparison of the evolution curves and images corresponding to first and second thawing shows indicators of accidental thawing. The monitoring of thawing process showed that its assessment can be reduced to the measurement of the water content lost by fish. The attempt to replace the original water lost by fish in first thawing is analyzed. The influence of the transducer frequency on fish thawing evaluation is tested.
文摘Objective: The aim of the study was to identify prognostic factors in non-small-cell lung cancer (NSCLC) with N2 nodal involvement.Methods: A retrospective analysis of disease free survival and 5-year survival for NSCLC patients who underwent primary surgical resection without neoadjuvant chemotherapy were performed.Between January 1998 and May 2004,133 patients were enrolled.Several factors such as age,sex,skip metastasis,number of N2 lymph node stations,type of resection,histology,adjuvant therapy etc.,were recorded and analyzed.SPSS 16.0 software was used.Results: Overall 5-year survival for 133 patients was 32.33%,5-year survival for single N2 station and multiple N2 stations sub-groups were 39.62% and 27.50% respectively,and 5-year survival for cN0–1 and cN2 sub-groups were 37.78% and 20.93% respectively.COX regression analysis revealed that number of N2 station (P = 0.013,OR: 0.490,95% CI: 0.427–0.781) and cN status (P = 0.009,OR: 0.607,95% CI: 0.372–0.992) were two favorable prognostic factors of survival.Conclusion: Number of N2 station and cN status were two favorable prognostic factors of survival.In restrict enrolled circumstances,after combined therapy made up of surgery and postoperative adjuvant therapy have been performed,satisfied survival could be achieved.