Aiming at the slow convergence and low accuracy problems of the traditional non-negative tensor factorization, a local hierarchical non-negative tensor factorization method is proposed by applying the local objective ...Aiming at the slow convergence and low accuracy problems of the traditional non-negative tensor factorization, a local hierarchical non-negative tensor factorization method is proposed by applying the local objective function theory to non- negative tensor factorization and combining the three semi-non- negative matrix factorization（NMF） model. The effectiveness of the method is verified by the facial feature extraction experiment. Through the decomposition of a series of an air compressor＇s vibration signals composed in the form of a bispectrum by this new method, the basis images representing the fault features and corresponding weight matrices are obtained. Then the relationships between characteristics and faults are analyzed and the fault types are classified by importing the weight matrices into the BP neural network. Experimental results show that the accuracy of fault diagnosis is improved by this new method compared with other feature extraction methods.展开更多
Aiming at the problems of bispectral analysis when applied to machinery fault diagnosis, a machinery fault feature extraction method based on sparseness-controlled non-negative tensor factorization （SNTF） is propose...Aiming at the problems of bispectral analysis when applied to machinery fault diagnosis, a machinery fault feature extraction method based on sparseness-controlled non-negative tensor factorization （SNTF） is proposed. First, a non-negative tensor factorization（NTF） algorithm is improved by imposing sparseness constraints on it. Secondly, the bispectral images of mechanical signals are obtained and stacked to form a third-order tensor. Thirdly, the improved algorithm is used to extract features, which are represented by a series of basis images from this tensor. Finally, coefficients indicating these basis images＇ weights in constituting original bispectral images are calculated for fault classification. Experiments on fault diagnosis of gearboxes show that the extracted features can not only reveal some nonlinear characteristics of the system, but also have intuitive meanings with regard to fault characteristic frequencies. These features provide great convenience for the interpretation of the relationships between machinery faults and corresponding bispectra.展开更多
[Objective] In order to better meet the requirement of crops on a more and more accurate water content under various planting environment of modern agri-culture, an automatic test system of soil water characteristic c...[Objective] In order to better meet the requirement of crops on a more and more accurate water content under various planting environment of modern agri-culture, an automatic test system of soil water characteristic curve was designed by combining the conceptions of soil moisture content and soil water potential. [Method] Electronic soil moisture tension meter was used to determine the real-time tension value of soil moisture in the tested container, and the electronic Weigh sensor was used to determine soil Weigh. Minusing method was used to calculate soil moisture content, based on which the soil water characteristic curve was plotted. [Result] Through the filed survey of 2 different kinds of soil in Jiangsu Province, the results were as fol ows： soil of different composition showed different trend in soil water characteristic curve that the soil water characteristic relation of the sandy soil in the old course of the Yel ow River in Xuzhou was Y=-0.000 2X3＋0.027 7X2-1.644 5X＋38.161, R2=0.991 9; while the soil water characteristic relation of the saline-alkali soil in Jinhai Farm of Dafeng was Y=-0.00 2X2-0.426X＋39.905, R2=0.991 3. [Con-clusion] The automatic test system of soil water characteristic curve soil water char-acteristics curve could reflect soil moisture content and soil water potential, as wel as reflect the effectiveness of soil water to plant growth, providing basis for the sci-entific irrigation.展开更多
Caroli's disease is a rare congenital condition chara- cterized by non-obstructive saccular or fusiform dilatation of larger intrahepatic bile ducts. Cholangitis, liver cirrhosis, and cholangiocarcinoma are its po...Caroli's disease is a rare congenital condition chara- cterized by non-obstructive saccular or fusiform dilatation of larger intrahepatic bile ducts. Cholangitis, liver cirrhosis, and cholangiocarcinoma are its potential complications. The diagnosis of Caroli's disease depends on demonstrating that the cystic lesions are in continuity with the biliary tree which can be showed by ultrasonography, computerized tomography, endoscopic retrograde cholangiopancreatography, percutaneous transhepatic cholangiography or magnetic resonance cholangiopancreatography. Treatment of Caroli's disease relies on the location of the biliary abnormalities. While localized forms confined to one lobe can be treated with surgery, liver transplantation is the only effective modality for diffuse forms. Although a rare disorder; Caroli's disease should always be considered in the differential diagnosis of chronic cholestasis of unknown cause.展开更多
This paper focuses on the economic development and urban morphology as well as its impact on the transportation system during the urban expansion of Shanghai in the last more than 20 years(1986-2008).Based on data fro...This paper focuses on the economic development and urban morphology as well as its impact on the transportation system during the urban expansion of Shanghai in the last more than 20 years(1986-2008).Based on data from 3 comprehensive transport surveys of Shanghai since 1986,the changes in residential trip demand,vehicle use,and the spatial distribution of trips were studied to understand the demands on the transportation system.The factors contributing to those changes in transportation demand were discussed,by which the conclusions were arrived:1) economic development promotes population growth and stimulates residential trip demand greatly;2) unsynchronized migration of population and job from central district to periphery district of Shanghai make trips and congestion diffuse in the same way;and 3) urban sprawl from a city center encourages the single-occupant vehicle mode,which imposes greater pressure on the roadway system.It is concluded that urban development should coordinate with the transportation system planning and expansion.展开更多
Heat transfer characteristics between the immersed heater and the bed content were studied in the riser of a liquid-solid circulating fluidized bed, whose diameter and height were 0.102 m (ID) and 2.5 m, respectively....Heat transfer characteristics between the immersed heater and the bed content were studied in the riser of a liquid-solid circulating fluidized bed, whose diameter and height were 0.102 m (ID) and 2.5 m, respectively. Effects of liquid velocity, particle size, surface tension of liquid phase and solid circulation rate on the overall heat transfer coefficient were examined. The heat transfer coefficient increased with increasing particle size or solid circulation rate due to the higher potential of particles to contact with the heater surface and promote turbulence near the heater surface. The value of heat transfer coefficient increased gradually with increase in the surface tension of liquid phase, due to the slight increase of solid holdup. The heat transfer coefficient increased with the liquid velocity even in the higher range, due to the solid circulation prevented the decrease in solid holdup, in contrast to that in the conventional liquid-solid fluidized beds. The values of heat transfer coefficient were well correlated in terms of dimensionless groups as well as operating variables.展开更多
Caroli's syndrome is characterized by multiple segmental cystic or saccular dilatations of intrahepatic bile ducts associated with congenital hepatic fibrosis. The clinical features of this syndrome reflect both t...Caroli's syndrome is characterized by multiple segmental cystic or saccular dilatations of intrahepatic bile ducts associated with congenital hepatic fibrosis. The clinical features of this syndrome reflect both the characteristics of congenital hepatic fibrosis such as portal hypertension and that of Caroli's disease named as recurrent cholangitis and cholelithiasis. The diagnosis depends on both histology and imaging methods which can show the communication between the sacculi and the bile ducts. Treatment consists of symptomatic treatment of cholangitis attacks by antibiotics, some endoscopic, radiological and surgical drainage procedures and surgery. Liver transplantation seems the ultimate treatment for this disease. Prognosis is fairly good unless recurrent cholangitis and renal failure develops.展开更多
Orthogonal-test-design method has been used to determine the optimal formula by phase behavior and interfacial tension studies, respectively. The effect of each component of two alkaline/surfactant/polymer flooding sy...Orthogonal-test-design method has been used to determine the optimal formula by phase behavior and interfacial tension studies, respectively. The effect of each component of two alkaline/surfactant/polymer flooding systems on interfacial tension is discussed, in which a low-price natural mixed carboxylate (SDC) is used as the major surfactant. The results indicate that the optimal composition is SDC (0.5%), alkaline NaHCO3/Na2CO3 with mass ratio of 1 (1.0%), and hydrolyzed polyacrylamide(0.1%). In the coreflood experiment, their oil recovery is increased by about 25.2% and 26.8% original oil in place, respectively.展开更多
Edge detection of potential field interpretation is an important task. The traditional edge detection methods have poor ability in outlining weak amplitude anomalies clearly. The resolved edges position is blurred.We ...Edge detection of potential field interpretation is an important task. The traditional edge detection methods have poor ability in outlining weak amplitude anomalies clearly. The resolved edges position is blurred.We purposed new edge detection methods based on directional eigenvalues of potential field gradient tensor for the causative sources. In order to balance strong and weak amplitude anomalies simultaneously,we present one normalization method using different orders of vertical derivatives to improve the new filters. The presented filters were tested on synthetic and real potential field data to verify its feasibility. All of the results have shown that the new edge detection methods can not only display the sources edges precisely and clearly,but also bring out more geological subtle details.展开更多
Esophageal duplication cysts are rare inherited lesions usually diagnosed in early childhood. Most of them are found in the mediastinum and manifest themselves as separate masses along or in continuity with the native...Esophageal duplication cysts are rare inherited lesions usually diagnosed in early childhood. Most of them are found in the mediastinum and manifest themselves as separate masses along or in continuity with the native esophagus. Their prevalence remains unknown and they are treated either surgically or endoscopically. In this report we describe a series of four adult patients in whom esophageal duplication cysts were Iocalised intramurally as masses pressing on the esophageal lumen and who were diagnosed with endoscopic ultrasonography. All patients were initially referred to other centres for upper gastroduodenoscopy due to nonspecific dyspeptic symptoms. After finding suspicious lesions in the esophagus their endoscopists referred them for endoscopic ultrasound examination at our centre. In two of the cases lesions mimicked esophageal varices and the other two submucosal tumours. In all four patients endoscopic ultrasonography has shown esophageal duplication cysts. Patients had no symptoms suggesting disease of the esophagusand required no treatment. As the true prevalence of esophageal cysts is unknown, it is very likely that in many patients, like in these four described by us, they may cause no symptoms, remain undetected and require no intervention. Increasing availability of new diagnostic modalities such as endoscopic ultrasonography may change the current view regarding the prevalence of esophageal duplication cysts and prove that they may1 in fact, not be such rare findings.展开更多
The structural features of fiber suspensions are dependent on the fiber alignment in the flows. In this work the orientation distribution function and orientation tensors for semi-concentrated fiber suspensions in ...The structural features of fiber suspensions are dependent on the fiber alignment in the flows. In this work the orientation distribution function and orientation tensors for semi-concentrated fiber suspensions in converging channel flow were calculated, and the evolutions of the fiber alignment and the bulk effective vis-cosity were analyzed. The results showed that the bulk stress and the effective viscosity were functions of therate-of-strain tensor and the fiber orientation state ; and that the fiber suspensions evolved to steady alignment and tended to concentrate to some preferred directions close to but not same as the directions of local stream-lines. The bulk effective viscosity depended on the product of Reynolds number and time. The decrease of ef-fective viscosity near the boundary benefited the increase of the rate of flow. Finally when the fiber alignment went into steady state, the structural features of fiber suspensions were not dependent on the Reynolds numberbut on the converging channel angle.展开更多
By the resultant theory, the E-characteristic polynomial of a real rectangular tensor is defined. It is proved that an E-singular value of a real rectangular tensor is always a root of the E-characteristic polynomial....By the resultant theory, the E-characteristic polynomial of a real rectangular tensor is defined. It is proved that an E-singular value of a real rectangular tensor is always a root of the E-characteristic polynomial. The definition of the regularity of square tensors is generalized to the rectangular tensors, and in the regular case, a root of the Echaracteristic polynomial of a special rectangular tensor is an E-singular value of the rectangular tensor. Moreover, the best rank-one approximation of a real partially symmetric rectangular tensor is investigated.展开更多
In this paper,an ADM mass formula for asymptotically de Sitter(dS) space-time is derived from theenergy-momentum tensor.We take the vacuum dS space as the background and investigate the ADM mass of the(d + 3)-dimensio...In this paper,an ADM mass formula for asymptotically de Sitter(dS) space-time is derived from theenergy-momentum tensor.We take the vacuum dS space as the background and investigate the ADM mass of the(d + 3)-dimensional sphere-symmetric space with a positive cosmological constant,and find that the ADM mass ofasymptotically dS space is based on the ADM mass of Schwarzschild field and the cosmological background brings somesmall mass contribution as well.展开更多
基金The National Natural Science Foundation of China(No.50875078)the Natural Science Foundation of Jiangsu Province(No.BK2007115)the National High Technology Research and Development Program of China(863 Program)(No.2007AA04Z421)
文摘Aiming at the slow convergence and low accuracy problems of the traditional non-negative tensor factorization, a local hierarchical non-negative tensor factorization method is proposed by applying the local objective function theory to non- negative tensor factorization and combining the three semi-non- negative matrix factorization（NMF） model. The effectiveness of the method is verified by the facial feature extraction experiment. Through the decomposition of a series of an air compressor＇s vibration signals composed in the form of a bispectrum by this new method, the basis images representing the fault features and corresponding weight matrices are obtained. Then the relationships between characteristics and faults are analyzed and the fault types are classified by importing the weight matrices into the BP neural network. Experimental results show that the accuracy of fault diagnosis is improved by this new method compared with other feature extraction methods.
基金The National Natural Science Foundation of China (No.50875048)the Natural Science Foundation of Jiangsu Province (No.BK2007115)the National High Technology Research and Development Program of China (863 Program)(No.2007AA04Z421)
文摘Aiming at the problems of bispectral analysis when applied to machinery fault diagnosis, a machinery fault feature extraction method based on sparseness-controlled non-negative tensor factorization （SNTF） is proposed. First, a non-negative tensor factorization（NTF） algorithm is improved by imposing sparseness constraints on it. Secondly, the bispectral images of mechanical signals are obtained and stacked to form a third-order tensor. Thirdly, the improved algorithm is used to extract features, which are represented by a series of basis images from this tensor. Finally, coefficients indicating these basis images＇ weights in constituting original bispectral images are calculated for fault classification. Experiments on fault diagnosis of gearboxes show that the extracted features can not only reveal some nonlinear characteristics of the system, but also have intuitive meanings with regard to fault characteristic frequencies. These features provide great convenience for the interpretation of the relationships between machinery faults and corresponding bispectra.
基金Supported by the Fund for Independent Innovation of Agricultural Sciences in Jiangsu Province(CX(13)3031)~~
文摘[Objective] In order to better meet the requirement of crops on a more and more accurate water content under various planting environment of modern agri-culture, an automatic test system of soil water characteristic curve was designed by combining the conceptions of soil moisture content and soil water potential. [Method] Electronic soil moisture tension meter was used to determine the real-time tension value of soil moisture in the tested container, and the electronic Weigh sensor was used to determine soil Weigh. Minusing method was used to calculate soil moisture content, based on which the soil water characteristic curve was plotted. [Result] Through the filed survey of 2 different kinds of soil in Jiangsu Province, the results were as fol ows： soil of different composition showed different trend in soil water characteristic curve that the soil water characteristic relation of the sandy soil in the old course of the Yel ow River in Xuzhou was Y=-0.000 2X3＋0.027 7X2-1.644 5X＋38.161, R2=0.991 9; while the soil water characteristic relation of the saline-alkali soil in Jinhai Farm of Dafeng was Y=-0.00 2X2-0.426X＋39.905, R2=0.991 3. [Con-clusion] The automatic test system of soil water characteristic curve soil water char-acteristics curve could reflect soil moisture content and soil water potential, as wel as reflect the effectiveness of soil water to plant growth, providing basis for the sci-entific irrigation.
文摘Caroli's disease is a rare congenital condition chara- cterized by non-obstructive saccular or fusiform dilatation of larger intrahepatic bile ducts. Cholangitis, liver cirrhosis, and cholangiocarcinoma are its potential complications. The diagnosis of Caroli's disease depends on demonstrating that the cystic lesions are in continuity with the biliary tree which can be showed by ultrasonography, computerized tomography, endoscopic retrograde cholangiopancreatography, percutaneous transhepatic cholangiography or magnetic resonance cholangiopancreatography. Treatment of Caroli's disease relies on the location of the biliary abnormalities. While localized forms confined to one lobe can be treated with surgery, liver transplantation is the only effective modality for diffuse forms. Although a rare disorder; Caroli's disease should always be considered in the differential diagnosis of chronic cholestasis of unknown cause.
基金Under the auspices of National Natural Science Foundation of China (No 70803034)
文摘This paper focuses on the economic development and urban morphology as well as its impact on the transportation system during the urban expansion of Shanghai in the last more than 20 years(1986-2008).Based on data from 3 comprehensive transport surveys of Shanghai since 1986,the changes in residential trip demand,vehicle use,and the spatial distribution of trips were studied to understand the demands on the transportation system.The factors contributing to those changes in transportation demand were discussed,by which the conclusions were arrived:1) economic development promotes population growth and stimulates residential trip demand greatly;2) unsynchronized migration of population and job from central district to periphery district of Shanghai make trips and congestion diffuse in the same way;and 3) urban sprawl from a city center encourages the single-occupant vehicle mode,which imposes greater pressure on the roadway system.It is concluded that urban development should coordinate with the transportation system planning and expansion.
基金Supported by Korea Institute of Energy Technology Evaluation and Planning (KETEP)GTL Technology Development Consortium (Korean National Oil Corp., Korea Gas Corp., Daelim Industrial Co. and Hyundai Engineering Co.) under "Energy Efficiency & Resources Programs" of the Ministry of Knowledge Economy, Republic of Korea
文摘Heat transfer characteristics between the immersed heater and the bed content were studied in the riser of a liquid-solid circulating fluidized bed, whose diameter and height were 0.102 m (ID) and 2.5 m, respectively. Effects of liquid velocity, particle size, surface tension of liquid phase and solid circulation rate on the overall heat transfer coefficient were examined. The heat transfer coefficient increased with increasing particle size or solid circulation rate due to the higher potential of particles to contact with the heater surface and promote turbulence near the heater surface. The value of heat transfer coefficient increased gradually with increase in the surface tension of liquid phase, due to the slight increase of solid holdup. The heat transfer coefficient increased with the liquid velocity even in the higher range, due to the solid circulation prevented the decrease in solid holdup, in contrast to that in the conventional liquid-solid fluidized beds. The values of heat transfer coefficient were well correlated in terms of dimensionless groups as well as operating variables.
文摘Caroli's syndrome is characterized by multiple segmental cystic or saccular dilatations of intrahepatic bile ducts associated with congenital hepatic fibrosis. The clinical features of this syndrome reflect both the characteristics of congenital hepatic fibrosis such as portal hypertension and that of Caroli's disease named as recurrent cholangitis and cholelithiasis. The diagnosis depends on both histology and imaging methods which can show the communication between the sacculi and the bile ducts. Treatment consists of symptomatic treatment of cholangitis attacks by antibiotics, some endoscopic, radiological and surgical drainage procedures and surgery. Liver transplantation seems the ultimate treatment for this disease. Prognosis is fairly good unless recurrent cholangitis and renal failure develops.
文摘Orthogonal-test-design method has been used to determine the optimal formula by phase behavior and interfacial tension studies, respectively. The effect of each component of two alkaline/surfactant/polymer flooding systems on interfacial tension is discussed, in which a low-price natural mixed carboxylate (SDC) is used as the major surfactant. The results indicate that the optimal composition is SDC (0.5%), alkaline NaHCO3/Na2CO3 with mass ratio of 1 (1.0%), and hydrolyzed polyacrylamide(0.1%). In the coreflood experiment, their oil recovery is increased by about 25.2% and 26.8% original oil in place, respectively.
基金financially supported by Sino Probe-09-01 Grant No. 201311192Project 2014100 Supported by Graduate Innovation Fund of Jilin University
文摘Edge detection of potential field interpretation is an important task. The traditional edge detection methods have poor ability in outlining weak amplitude anomalies clearly. The resolved edges position is blurred.We purposed new edge detection methods based on directional eigenvalues of potential field gradient tensor for the causative sources. In order to balance strong and weak amplitude anomalies simultaneously,we present one normalization method using different orders of vertical derivatives to improve the new filters. The presented filters were tested on synthetic and real potential field data to verify its feasibility. All of the results have shown that the new edge detection methods can not only display the sources edges precisely and clearly,but also bring out more geological subtle details.
文摘Esophageal duplication cysts are rare inherited lesions usually diagnosed in early childhood. Most of them are found in the mediastinum and manifest themselves as separate masses along or in continuity with the native esophagus. Their prevalence remains unknown and they are treated either surgically or endoscopically. In this report we describe a series of four adult patients in whom esophageal duplication cysts were Iocalised intramurally as masses pressing on the esophageal lumen and who were diagnosed with endoscopic ultrasonography. All patients were initially referred to other centres for upper gastroduodenoscopy due to nonspecific dyspeptic symptoms. After finding suspicious lesions in the esophagus their endoscopists referred them for endoscopic ultrasound examination at our centre. In two of the cases lesions mimicked esophageal varices and the other two submucosal tumours. In all four patients endoscopic ultrasonography has shown esophageal duplication cysts. Patients had no symptoms suggesting disease of the esophagusand required no treatment. As the true prevalence of esophageal cysts is unknown, it is very likely that in many patients, like in these four described by us, they may cause no symptoms, remain undetected and require no intervention. Increasing availability of new diagnostic modalities such as endoscopic ultrasonography may change the current view regarding the prevalence of esophageal duplication cysts and prove that they may1 in fact, not be such rare findings.
文摘The structural features of fiber suspensions are dependent on the fiber alignment in the flows. In this work the orientation distribution function and orientation tensors for semi-concentrated fiber suspensions in converging channel flow were calculated, and the evolutions of the fiber alignment and the bulk effective vis-cosity were analyzed. The results showed that the bulk stress and the effective viscosity were functions of therate-of-strain tensor and the fiber orientation state ; and that the fiber suspensions evolved to steady alignment and tended to concentrate to some preferred directions close to but not same as the directions of local stream-lines. The bulk effective viscosity depended on the product of Reynolds number and time. The decrease of ef-fective viscosity near the boundary benefited the increase of the rate of flow. Finally when the fiber alignment went into steady state, the structural features of fiber suspensions were not dependent on the Reynolds numberbut on the converging channel angle.
文摘By the resultant theory, the E-characteristic polynomial of a real rectangular tensor is defined. It is proved that an E-singular value of a real rectangular tensor is always a root of the E-characteristic polynomial. The definition of the regularity of square tensors is generalized to the rectangular tensors, and in the regular case, a root of the Echaracteristic polynomial of a special rectangular tensor is an E-singular value of the rectangular tensor. Moreover, the best rank-one approximation of a real partially symmetric rectangular tensor is investigated.
基金Supported by the Natural Science Foundation of China under Grant No.10875060
文摘In this paper,an ADM mass formula for asymptotically de Sitter(dS) space-time is derived from theenergy-momentum tensor.We take the vacuum dS space as the background and investigate the ADM mass of the(d + 3)-dimensional sphere-symmetric space with a positive cosmological constant,and find that the ADM mass ofasymptotically dS space is based on the ADM mass of Schwarzschild field and the cosmological background brings somesmall mass contribution as well.
