The T-joints of Ti?6Al?4V alloy were manufactured by double-sided synchronized laser beam welding with the homologous filler wire. The formation, microstructure and mechanical properties of welded joints as well as th...The T-joints of Ti?6Al?4V alloy were manufactured by double-sided synchronized laser beam welding with the homologous filler wire. The formation, microstructure and mechanical properties of welded joints as well as the correlations of each other were investigated. The results indicate that the quality of weld seams is good without defects such as discontinuity, beading, visible cracks or porosity, which is linked to the steady molten pool behavior and droplet transition. The morphologies of the heat affected zone (HAZ) located on the skin and stringer are disparate. The microstructure of the HAZ and fusion zone (FZ) is mainly comprised of acicular martensiticα′ phases. The microhardness of the HAZ and FZ is higher than that of the base metal (BM) and reaches a maximum value at the HAZ near FZ on the stringer. The tensile specimens along the skin and stringer fractured at the BM with ductile fracture surfaces.展开更多
Fatigue behavior of AZ31B magnesium alloy electron beam welded joint undergoing cyclic loading was investigated by infrared thermography. Temperature evolution throughout a fatigue process was presented and the mechan...Fatigue behavior of AZ31B magnesium alloy electron beam welded joint undergoing cyclic loading was investigated by infrared thermography. Temperature evolution throughout a fatigue process was presented and the mechanism of heat generationwas discussed. Fatigue limit of the welded joint was predicted and the fatigue damage was also assessed based ontheevolution of the temperatureand hotspot zone on the specimen surfaceduring fatigue tests. The presented results show that infrared thermography can not onlyquicklypredict the fatigue behavior of the welded joint, but also qualitatively identify the evolution of fatigue damage in real time. It is found that the predicted fatigue limit agrees well with the conventionalS-Nexperimental results. The evolution of the temperatureand hotspot zone on the specimen surface can be an effectivefatigue damage indicatorfor effectiveevaluationof magnesium alloy electron beam welded joint.展开更多
AIM:To explore the feasibility of dual camera capsule (DCC)small-bowel(SB)imaging and to examine if two cameras complement each other to detect more SB lesions.METHODS:Forty-one eligible,consecutive patients underwent...AIM:To explore the feasibility of dual camera capsule (DCC)small-bowel(SB)imaging and to examine if two cameras complement each other to detect more SB lesions.METHODS:Forty-one eligible,consecutive patients underwent DCC SB imaging.Two experienced investigators examined the videos and compared the total number of detected lesions to the number of lesions detected by each camera separately.Examination tolerability was assessed using a questionnaire.RESULTS:One patient was excluded.DCC cameras detected 68 positive findings(POS)in 20(50%)cases.Fifty of them were detected by the"yellow"camera,48 by the"green"and 28 by both cameras;44%(n=22)of the"yellow"camera’s POS were not detected by the"green"camera and 42%(n=20)of the"green" camera’s POS were not detected by the"yellow"camera.In two cases,only one camera detected significant findings.All participants had 216 findings of unknown significance(FUS).The"yellow","green"and both cameras detected 171,161,and 116 FUS,respectively;32%(n=55)of the"yellow"camera’s FUS were not detected by the"green"camera and 28%(n=45)of the"green"camera’s FUS were not detected by the "yellow"camera.There were no complications related to the examination,and 97.6%of the patients would repeat the examination,if necessary.CONCLUSION:DCC SB examination is feasible and well tolerated.The two cameras complement each other to detect more SB lesions.展开更多
Objective: To investigate the diagnostic potential value of ^99Tc-MIBI imaging in head and neck tumors. Methods: Ninety-one patients with malignant and benign head and neck lesions were subjected to ^99mTc-MIBI tomo...Objective: To investigate the diagnostic potential value of ^99Tc-MIBI imaging in head and neck tumors. Methods: Ninety-one patients with malignant and benign head and neck lesions were subjected to ^99mTc-MIBI tomography, and 20 healthy volunteers served as control group. Results: The overall sensitivity,specificity, accuracy and positive predictive accuracy of early/delay ^99mTc-MIBI imaging in diagnosis of head and neck malignant tumors were 78.7%/72.3%, 72.1%/88.4%, 75.6%/80.0% and 75.5%/87.2% respectively. The results of ^99mTc-MIBI Imaging in diagnosis of nasopharyngeal cancer and sinonasal non-Hodgkin's lymphoma were more satisfactory than those in maxillary sinus cancer. In distinguishing recurrent/residual nasopharyngeal carcinoma and sinonasal non-Hodgkin's lymphoma, ^99mTc-MIBI scintigraphy was superior to CT/MRI. Conclusion: ^99mTc-MIBI imaging is a promising useful tool in identifying head and neck tumor, and it has a special value to evaluate the local invasion and metastasis involved.展开更多
The study on Traditional Chinese Medicine (TCM)by the technology and method of thermal science is a new cut in point in interdisciplinary science, and its purpose is to study the tongue inspection in TCM from the view...The study on Traditional Chinese Medicine (TCM)by the technology and method of thermal science is a new cut in point in interdisciplinary science, and its purpose is to study the tongue inspection in TCM from the view of the bio heat transfer theory. In this paper human tongues were studied with the infrared thermal imaging technology. And the characteristic relationship between temperature distribution and age, tongue color as well as infrared thermal tongue image concerning the characteristic of viscera was analyzed by the experimental data,which confirms that the change in temperature distribution in different positions of the tongue is related to the diseases of different internal organs of the body. From a series of invasive experiments in animals, the blood perfusion rate was measured with the equipment of CBI 8000 Doppler Blood Flow Meter and MP 100 Physiologic Research System for the first time and the characteristic relationship curve between the temperature on the surface of the tongue and the blood perfusion rate was obtained. From the experiments the temperature on the surface of the tongue reflects objectively the tongue color which is influenced by the blood perfusion rate. This will help to develop some new cognition in the theory of TCM.展开更多
Although information regarding the initiation processes of debris flows is important for the development of mitigation measures,field data regarding these processes are scarce.We conducted field observations of debris...Although information regarding the initiation processes of debris flows is important for the development of mitigation measures,field data regarding these processes are scarce.We conducted field observations of debris-flow initiation processes in the upper Ichinosawa catchment of the Ohya landslide,central Japan.On 19 June 2012,our videocamera monitoring systems recorded the moment of debris-flow initiation on channel deposits(nine surges) and talus slopes(eight surges).The initiation mechanisms of these surges were classified into three types by analyzing the video images: erosion by the surface flow,movement of deposits as a mass,and upward development of the fluid area.The first type was associated with the progress of surface flow from the upper stream on unsaturated channel deposits.The second type was likely caused by an increase in the pore water pressure associated with the rising in the groundwater level in channel deposits;a continuous water supply from the upper stream by the surface flow might have induced this saturation.The third type was associated with changes in the downstream topography caused by erosion.The flow velocity of most surges was less than 3 m s^(-1) and they usually stopped within 100 m from the initiation point.Surges with abundant pore fluid had a higher flow velocity(about 3- 5 m s^(-1)) and could travel for alonger duration.Our observations indicate that the surface flow plays an important role in the initiation of debris flows on channel deposits and talus slopes.展开更多
AIM: To retrospectively analyze the imaging features of solid-pseudopapillary tumors (SPTs) of the pancreas on multi-detector row computed tomography (MDCT) and define the imaging findings suggestive of malignant...AIM: To retrospectively analyze the imaging features of solid-pseudopapillary tumors (SPTs) of the pancreas on multi-detector row computed tomography (MDCT) and define the imaging findings suggestive of malignant potential. METHODS: A total of 24 consecutive cases with surgically and pathologically confirmed SPTs of the pancreas underwent preoperative abdominal MDCT studies in our hospital. All axial CT images, CT angiographic images, and coronally and sagittally reformed images were obtained. The images were retrospectively reviewed at interactive picture archiving and communication system workstations. RESULTS: Of the 24 cases of SPTs, 11 cases (45.8%) occurred in the pancreatic head and seven (29.1%) in the tail. Eighteen were pathologically diagnosed as benign and six as malignant. MDCT diagnosis of SPTs was well correlated with the surgical and pathological results (Kappa = 0.6, P 〈 0.05). The size of SPTs ranged from 3 to 15 cm (mean, 5.8 cm). When the size of the tumor was greater than 6 cm (including 6 cm), the possibilities of vascular (8 vs 1) and capsular invasion (9 vs 0) increased significantly (P 〈 0.05).Two pathologically benign cases with vascular invasion and disrupted capsule on MDCT presented with local recurrence and hepatic metastases during follow-up about 1 year after the resection of the primary tumors. CONCLUSION: Vascular and capsular invasion with superimposed spread into the adjacent pancreatic parenchyrna and nearby structures in SPTs of the pancreas can be accurately revealed by MDCT preoperatively. These imaging findings are predictive of the malignant potential associated with the aggressive behavior of the tumor, even in the pathologically benign cases.展开更多
In view of the images collection and processing problems of the smart car camera, the paper introduces a method which deals with field and line synchronization signal separation and binarization processing of the vide...In view of the images collection and processing problems of the smart car camera, the paper introduces a method which deals with field and line synchronization signal separation and binarization processing of the video signal collected from track fields, and which is capable to extract and position black border trajectory images effectively. According to the experiment results of the method, the camera images can be collected and processed effectively, and the accurate image information can be provided for the smart cars to travel along the track. The method has the advantages of being easy to use, strong adaptability, ideal performance and high practical value. On the basis of advantages the method is of high practical value in smart car races.展开更多
Three dimensional digitization of human head is desired in many applications. In this paper, an information fusion based scheme is presented to obtain 3-D information of human head. Structured light technology is empl...Three dimensional digitization of human head is desired in many applications. In this paper, an information fusion based scheme is presented to obtain 3-D information of human head. Structured light technology is employed to measure depth. For the special reflection areas,in which the structured light stripe can not be detected directly, the shape of the structured light stripe can be calculated from the corresponding contour. By fusing the information of structured light and the contours, the problem of reflectance influence is solved, and the whole shape of head,including hair area, can be obtained. Some good results are obtained.展开更多
Autofocus method based on the analysis of image content information is investigated to reduce the alignment error resulting from mark positioning uncertainty due to defocus in microstructure layered fabrication proces...Autofocus method based on the analysis of image content information is investigated to reduce the alignment error resulting from mark positioning uncertainty due to defocus in microstructure layered fabrication process based on multilevel imprint lithography. The applicability of several autofocus functions to the alignment mark images is evaluated concerning their uniformity, sharpness near peak, reliability and measure computation efficiency and the most suitable one based on power spectrum in frequency domain (PSFD) is adopted. To solve the problem of too much computation amount needed in PSFD algorithm, the strategy of interested region detection and effective image reconstruction is proposed and the algorithm efficiency is improved. The test results show that the computation time is reduced from 0.316 s to 0.023 s under the same conditions while the other merits of the function are preserved, which indicates that the modified algorithm can meet the mark image autofocusing requirements in response time, accuracy and robustness. The alignment error due to defocus which is about 0.5 μm indicated by experimental results can be reduced or eliminated by the autofocusing implementation.展开更多
Multi-sensor coordinate unification in dimensional metrology is used in order to get holistic, more accurate and reliable information about a workpiece based on several or multiple measurement values from ...Multi-sensor coordinate unification in dimensional metrology is used in order to get holistic, more accurate and reliable information about a workpiece based on several or multiple measurement values from one or more sensors. Because of the problem that standard ball is deficient as a standard artifact in the coordinate unification of high-precision composite measurement in two dimensions (2D) , a new method is proposed in this paper which uses angle gauge blocks as standard artifacts to achieve coordinate unification between the image sensor and the tactile probe. By comparing the standard ball with the angle gauge block as a standard artifact, theoretical analysis and experimental results are given to prove that it is more precise and more convenient to use angle gauge blocks as standard artifacts to achieve coordinate unification of high-precision composite measurement in two dimensions.展开更多
A noncontact user interface using image processing for people with neuromuscular diseases is presented in this paper. The user interface is composed of a Web camera and a PC, and allows users to manipulate the PC usin...A noncontact user interface using image processing for people with neuromuscular diseases is presented in this paper. The user interface is composed of a Web camera and a PC, and allows users to manipulate the PC using small movements of single finger. By using image processing techniques with the Web camera, the finger is appropriately detected from the images captured by it. Control boxes for pointing and text input functions are also made. To verify performances of the interface, some tasks are experimentally performed by three able-bodied subjects and a person suffering from spinal muscular atrophy. It was clear from the experimental results that all the subjects could smoothly nerforrn the t,~k~展开更多
This paper proposes a self-position estimate algorithm for the multiple mobile robots; each robot uses two omnidirectional cameras and an accelerometer. In recent years, the Great East Japan Earthquake and large-scale...This paper proposes a self-position estimate algorithm for the multiple mobile robots; each robot uses two omnidirectional cameras and an accelerometer. In recent years, the Great East Japan Earthquake and large-scale disasters have occurred frequently in Japan. From this, development of the searching robot which supports the rescue team to perform a relief activity at a large-scale disaster is indispensable. Then, this research has developed the searching robot group system with two or more mobile robots. In this research, the searching robot equips with two omnidirectional cameras and an accelerometer. In order to perform distance measurement using two omnidirectional cameras, each parameter of an omnidirectional camera and the position and posture between two omnidirectional cameras have to be calibrated in advance. If there are few mobile robots, the calibration time of each omnidirectional camera does not pose a problem. However, if the calibration is separately performed when using two or more robots in a disaster site, etc., it will take huge calibration time. Then, this paper proposed the algorithm which estimates a mobile robot's position and the parameter of the position and posture between two omnidirectional cameras simultaneously. The algorithm proposed in this paper extended Nonlinear Transformation (NLT) Method. This paper conducted the simulation experiment to check the validity of the proposed algorithm. In some simulation experiments, one mobile robot moves and observes the circumference of another mobile robot which has stopped at a certain place. This paper verified whether the mobile robot can estimate position using the measurement value when the number of observation times becomes 10 times in n/18 of observation intervals. The result of the simulation shows the effectiveness of the algorithm.展开更多
Recently the improved robot working in very various fields, many researchers are trying to develop the robot to help people in the service field. However people who meet a robot in the first time gen- erally get heter...Recently the improved robot working in very various fields, many researchers are trying to develop the robot to help people in the service field. However people who meet a robot in the first time gen- erally get heterogeneous feeling. To resolve this, we suggest an inter- active game with robots to increase the friendliness. The game, called "Divi-Divi-Dip" with 3 different body poses, is first introduced in a Korean TV prgrmn. The robot is using the visionary technology to recognize the pose with camera for the interactive game.展开更多
In order to precisely measure the diameters for obtaining the fineness of rolling raw silk, the physical features of raw silk are analyzed. By means of Fresnel principle, diffractions caused by different transparent r...In order to precisely measure the diameters for obtaining the fineness of rolling raw silk, the physical features of raw silk are analyzed. By means of Fresnel principle, diffractions caused by different transparent raw silk filaments are analyzed and simulated. Image data of raw silk filament measured by digital CMOS camera are analyzed and processed for obtaining the precise diameters of the filamerit with the relative error of less than 1%. On the assumption of appropriate elliptic cross-section of the filament, the cross-section area is calculated as the fineness of the filament. Measurement experiments are carded out. Finally, some suggestions are proposed for photoelectric measuring the fineness of raw silk.展开更多
The infrared camera is a curious object for the animals of Changtang.Often covered in camouflage or army green,it looks very"professional".But once I saw the photos they took,I knew the camouflage did not wo...The infrared camera is a curious object for the animals of Changtang.Often covered in camouflage or army green,it looks very"professional".But once I saw the photos they took,I knew the camouflage did not work at all.Most animals could see the cameras without any problem.Some of them showed various degrees of interest in the cameras,while others acted indifferently.To tell the truth,it is not easy to hide something in Changtang.展开更多
Objective To analyze the clinical and ultrasonographic imaging features of intraductal papillary mutinous neoplasm (1PMN) of the pancreas. Methods Twelve patients with IPMN underwent surgery between May 2005 and De...Objective To analyze the clinical and ultrasonographic imaging features of intraductal papillary mutinous neoplasm (1PMN) of the pancreas. Methods Twelve patients with IPMN underwent surgery between May 2005 and December 2008, including 4 (33.3%) with adenoma and 8 (66.7%) with adenocarcinoma. IPMN was classified preoperatively into 3 types based on sonographic findings of different sites: main duct, branch duct, and combined type. All clinical presentations and ultrasonographic findings of those paticnts were reviewed and the correlation be- tween ultrasonographic hndings and histopathological results was analyzed. Results There were 9 men and 3 women with a mean age of 60.1±9.6 years (range, 32-73). OF all the 12 patients with IPMN, 9 (75.0%) had experienced some symptoms of epigastric discomfort and/or pain as cell as backache; 7 cases were with medical history of acute pancreatitis, 5 cases with diabetes, 4 cases with elevated CA19-9, and 2 cases with steatorrhea. All lesions of IPMN have been revealed by transabdominal ul- trasonography. The mean diameters of the lesions were 1.4±0.8 cm (range, 0.5-2.0) and 6.3±6.0 cm (range, 2.0-20.0) in adenomas and adenocarcinomas, respectively. And the mean diameters of the main duct in adelnomas and adenocarcinomas were 1.0±0.8 cm and 1.6±1.0 cm, respectively. Among the 4 adnomas, 3 (75.0%) cases were classified as branch type based on sonographic findings, and 2 were demonstrated as mural nodules in which no color signals was detected. Among the 8 adenocarcinomas, 5 (62.5%) cases were classifled as main duct type, and 3 (37.5%) as combined type. In 7 of the 8 adcnocarcinomas, mural nodules were detected within the dilated ducts or cysts of the lesions in which color flow signals were detected. Conclusions Transabdominal ultrasonography can reveal the pancreatic cystic lesions of IPMN as well as dilated pancreatic: ducts. Some characteristics should be noticed as suggesting the possibility of malignancy: clinical symptoms of pancreatic insufficiency, large tumor size, and mural nodules with color Doppler flow signals. Transabdominal ultrasonography could be a useful tool to help diagnose and make appropriate management of IPMN.展开更多
GANGLIONEUROMA is considered as the most mature and noninvasive form of neuroblastic tumors. It derives from neural crest cells, and can arise from wherever sympathetic tissue exists, including neck, posterior medias...GANGLIONEUROMA is considered as the most mature and noninvasive form of neuroblastic tumors. It derives from neural crest cells, and can arise from wherever sympathetic tissue exists, including neck, posterior mediastinum, adrenal gland, retroperitoneum and pelvis. The two most common locations for this tumor are retroperitoneum and posterior mediastinum; infrequently it occurs in the intracranial re-gion,2-8 with only three cases has been reported arising from trigeminal nerve.2-4 The current paper presents a 49-year-old male patient with a ganglioneuroma arising from right trigeminal ganglion and extending to the mid-dle-posterior cranial fossa. We summarized the clinical and diagnostic characteristics of this extremely rare tumor, in comparison with the three reported cases in literatures.展开更多
基金Project supported by Science and Technology on Power Beam Processes Laboratory at Beijing Aeronautical Manufacturing Technology Research Institute,China
文摘The T-joints of Ti?6Al?4V alloy were manufactured by double-sided synchronized laser beam welding with the homologous filler wire. The formation, microstructure and mechanical properties of welded joints as well as the correlations of each other were investigated. The results indicate that the quality of weld seams is good without defects such as discontinuity, beading, visible cracks or porosity, which is linked to the steady molten pool behavior and droplet transition. The morphologies of the heat affected zone (HAZ) located on the skin and stringer are disparate. The microstructure of the HAZ and fusion zone (FZ) is mainly comprised of acicular martensiticα′ phases. The microhardness of the HAZ and FZ is higher than that of the base metal (BM) and reaches a maximum value at the HAZ near FZ on the stringer. The tensile specimens along the skin and stringer fractured at the BM with ductile fracture surfaces.
基金Project(51305292)supported by the National Natural Science Foundation of ChinaProject(20105429001)supported by the National Aeronautical Science Foundation of China
文摘Fatigue behavior of AZ31B magnesium alloy electron beam welded joint undergoing cyclic loading was investigated by infrared thermography. Temperature evolution throughout a fatigue process was presented and the mechanism of heat generationwas discussed. Fatigue limit of the welded joint was predicted and the fatigue damage was also assessed based ontheevolution of the temperatureand hotspot zone on the specimen surfaceduring fatigue tests. The presented results show that infrared thermography can not onlyquicklypredict the fatigue behavior of the welded joint, but also qualitatively identify the evolution of fatigue damage in real time. It is found that the predicted fatigue limit agrees well with the conventionalS-Nexperimental results. The evolution of the temperatureand hotspot zone on the specimen surface can be an effectivefatigue damage indicatorfor effectiveevaluationof magnesium alloy electron beam welded joint.
文摘AIM:To explore the feasibility of dual camera capsule (DCC)small-bowel(SB)imaging and to examine if two cameras complement each other to detect more SB lesions.METHODS:Forty-one eligible,consecutive patients underwent DCC SB imaging.Two experienced investigators examined the videos and compared the total number of detected lesions to the number of lesions detected by each camera separately.Examination tolerability was assessed using a questionnaire.RESULTS:One patient was excluded.DCC cameras detected 68 positive findings(POS)in 20(50%)cases.Fifty of them were detected by the"yellow"camera,48 by the"green"and 28 by both cameras;44%(n=22)of the"yellow"camera’s POS were not detected by the"green"camera and 42%(n=20)of the"green" camera’s POS were not detected by the"yellow"camera.In two cases,only one camera detected significant findings.All participants had 216 findings of unknown significance(FUS).The"yellow","green"and both cameras detected 171,161,and 116 FUS,respectively;32%(n=55)of the"yellow"camera’s FUS were not detected by the"green"camera and 28%(n=45)of the"green"camera’s FUS were not detected by the "yellow"camera.There were no complications related to the examination,and 97.6%of the patients would repeat the examination,if necessary.CONCLUSION:DCC SB examination is feasible and well tolerated.The two cameras complement each other to detect more SB lesions.
文摘Objective: To investigate the diagnostic potential value of ^99Tc-MIBI imaging in head and neck tumors. Methods: Ninety-one patients with malignant and benign head and neck lesions were subjected to ^99mTc-MIBI tomography, and 20 healthy volunteers served as control group. Results: The overall sensitivity,specificity, accuracy and positive predictive accuracy of early/delay ^99mTc-MIBI imaging in diagnosis of head and neck malignant tumors were 78.7%/72.3%, 72.1%/88.4%, 75.6%/80.0% and 75.5%/87.2% respectively. The results of ^99mTc-MIBI Imaging in diagnosis of nasopharyngeal cancer and sinonasal non-Hodgkin's lymphoma were more satisfactory than those in maxillary sinus cancer. In distinguishing recurrent/residual nasopharyngeal carcinoma and sinonasal non-Hodgkin's lymphoma, ^99mTc-MIBI scintigraphy was superior to CT/MRI. Conclusion: ^99mTc-MIBI imaging is a promising useful tool in identifying head and neck tumor, and it has a special value to evaluate the local invasion and metastasis involved.
基金SupportedbyNationalNaturalScienceFoundationofChina(No.59976026ndTianjinNaturalScienceFoundation (No .0 0 36 0 771 1 )
文摘The study on Traditional Chinese Medicine (TCM)by the technology and method of thermal science is a new cut in point in interdisciplinary science, and its purpose is to study the tongue inspection in TCM from the view of the bio heat transfer theory. In this paper human tongues were studied with the infrared thermal imaging technology. And the characteristic relationship between temperature distribution and age, tongue color as well as infrared thermal tongue image concerning the characteristic of viscera was analyzed by the experimental data,which confirms that the change in temperature distribution in different positions of the tongue is related to the diseases of different internal organs of the body. From a series of invasive experiments in animals, the blood perfusion rate was measured with the equipment of CBI 8000 Doppler Blood Flow Meter and MP 100 Physiologic Research System for the first time and the characteristic relationship curve between the temperature on the surface of the tongue and the blood perfusion rate was obtained. From the experiments the temperature on the surface of the tongue reflects objectively the tongue color which is influenced by the blood perfusion rate. This will help to develop some new cognition in the theory of TCM.
基金supported by the Grant-in-Aid for Scientific Research of Japan Society for the Promotion of Science (JSPS KAKENHI) (Grant Nos.80378918,26292077)
文摘Although information regarding the initiation processes of debris flows is important for the development of mitigation measures,field data regarding these processes are scarce.We conducted field observations of debris-flow initiation processes in the upper Ichinosawa catchment of the Ohya landslide,central Japan.On 19 June 2012,our videocamera monitoring systems recorded the moment of debris-flow initiation on channel deposits(nine surges) and talus slopes(eight surges).The initiation mechanisms of these surges were classified into three types by analyzing the video images: erosion by the surface flow,movement of deposits as a mass,and upward development of the fluid area.The first type was associated with the progress of surface flow from the upper stream on unsaturated channel deposits.The second type was likely caused by an increase in the pore water pressure associated with the rising in the groundwater level in channel deposits;a continuous water supply from the upper stream by the surface flow might have induced this saturation.The third type was associated with changes in the downstream topography caused by erosion.The flow velocity of most surges was less than 3 m s^(-1) and they usually stopped within 100 m from the initiation point.Surges with abundant pore fluid had a higher flow velocity(about 3- 5 m s^(-1)) and could travel for alonger duration.Our observations indicate that the surface flow plays an important role in the initiation of debris flows on channel deposits and talus slopes.
基金Supported by Shanghai Leading Academic Discipline Project (S30203)
文摘AIM: To retrospectively analyze the imaging features of solid-pseudopapillary tumors (SPTs) of the pancreas on multi-detector row computed tomography (MDCT) and define the imaging findings suggestive of malignant potential. METHODS: A total of 24 consecutive cases with surgically and pathologically confirmed SPTs of the pancreas underwent preoperative abdominal MDCT studies in our hospital. All axial CT images, CT angiographic images, and coronally and sagittally reformed images were obtained. The images were retrospectively reviewed at interactive picture archiving and communication system workstations. RESULTS: Of the 24 cases of SPTs, 11 cases (45.8%) occurred in the pancreatic head and seven (29.1%) in the tail. Eighteen were pathologically diagnosed as benign and six as malignant. MDCT diagnosis of SPTs was well correlated with the surgical and pathological results (Kappa = 0.6, P 〈 0.05). The size of SPTs ranged from 3 to 15 cm (mean, 5.8 cm). When the size of the tumor was greater than 6 cm (including 6 cm), the possibilities of vascular (8 vs 1) and capsular invasion (9 vs 0) increased significantly (P 〈 0.05).Two pathologically benign cases with vascular invasion and disrupted capsule on MDCT presented with local recurrence and hepatic metastases during follow-up about 1 year after the resection of the primary tumors. CONCLUSION: Vascular and capsular invasion with superimposed spread into the adjacent pancreatic parenchyrna and nearby structures in SPTs of the pancreas can be accurately revealed by MDCT preoperatively. These imaging findings are predictive of the malignant potential associated with the aggressive behavior of the tumor, even in the pathologically benign cases.
文摘In view of the images collection and processing problems of the smart car camera, the paper introduces a method which deals with field and line synchronization signal separation and binarization processing of the video signal collected from track fields, and which is capable to extract and position black border trajectory images effectively. According to the experiment results of the method, the camera images can be collected and processed effectively, and the accurate image information can be provided for the smart cars to travel along the track. The method has the advantages of being easy to use, strong adaptability, ideal performance and high practical value. On the basis of advantages the method is of high practical value in smart car races.
基金Supported by the National Natural Science Foundation of China(69775022) and 863 Programme of China(863-306-ZT04-06-3)
文摘Three dimensional digitization of human head is desired in many applications. In this paper, an information fusion based scheme is presented to obtain 3-D information of human head. Structured light technology is employed to measure depth. For the special reflection areas,in which the structured light stripe can not be detected directly, the shape of the structured light stripe can be calculated from the corresponding contour. By fusing the information of structured light and the contours, the problem of reflectance influence is solved, and the whole shape of head,including hair area, can be obtained. Some good results are obtained.
基金Supported by National Natural Science Foundation of China (No50305026)Open Foundation of Guangxi Key Lab for Manufacturing Systems and Advanced Manufacturing Technology (No07109008-025-K)
文摘Autofocus method based on the analysis of image content information is investigated to reduce the alignment error resulting from mark positioning uncertainty due to defocus in microstructure layered fabrication process based on multilevel imprint lithography. The applicability of several autofocus functions to the alignment mark images is evaluated concerning their uniformity, sharpness near peak, reliability and measure computation efficiency and the most suitable one based on power spectrum in frequency domain (PSFD) is adopted. To solve the problem of too much computation amount needed in PSFD algorithm, the strategy of interested region detection and effective image reconstruction is proposed and the algorithm efficiency is improved. The test results show that the computation time is reduced from 0.316 s to 0.023 s under the same conditions while the other merits of the function are preserved, which indicates that the modified algorithm can meet the mark image autofocusing requirements in response time, accuracy and robustness. The alignment error due to defocus which is about 0.5 μm indicated by experimental results can be reduced or eliminated by the autofocusing implementation.
基金National Key Scientific Instrument and Equipment Development Project(No.2013YQ170539)
文摘Multi-sensor coordinate unification in dimensional metrology is used in order to get holistic, more accurate and reliable information about a workpiece based on several or multiple measurement values from one or more sensors. Because of the problem that standard ball is deficient as a standard artifact in the coordinate unification of high-precision composite measurement in two dimensions (2D) , a new method is proposed in this paper which uses angle gauge blocks as standard artifacts to achieve coordinate unification between the image sensor and the tactile probe. By comparing the standard ball with the angle gauge block as a standard artifact, theoretical analysis and experimental results are given to prove that it is more precise and more convenient to use angle gauge blocks as standard artifacts to achieve coordinate unification of high-precision composite measurement in two dimensions.
文摘A noncontact user interface using image processing for people with neuromuscular diseases is presented in this paper. The user interface is composed of a Web camera and a PC, and allows users to manipulate the PC using small movements of single finger. By using image processing techniques with the Web camera, the finger is appropriately detected from the images captured by it. Control boxes for pointing and text input functions are also made. To verify performances of the interface, some tasks are experimentally performed by three able-bodied subjects and a person suffering from spinal muscular atrophy. It was clear from the experimental results that all the subjects could smoothly nerforrn the t,~k~
文摘This paper proposes a self-position estimate algorithm for the multiple mobile robots; each robot uses two omnidirectional cameras and an accelerometer. In recent years, the Great East Japan Earthquake and large-scale disasters have occurred frequently in Japan. From this, development of the searching robot which supports the rescue team to perform a relief activity at a large-scale disaster is indispensable. Then, this research has developed the searching robot group system with two or more mobile robots. In this research, the searching robot equips with two omnidirectional cameras and an accelerometer. In order to perform distance measurement using two omnidirectional cameras, each parameter of an omnidirectional camera and the position and posture between two omnidirectional cameras have to be calibrated in advance. If there are few mobile robots, the calibration time of each omnidirectional camera does not pose a problem. However, if the calibration is separately performed when using two or more robots in a disaster site, etc., it will take huge calibration time. Then, this paper proposed the algorithm which estimates a mobile robot's position and the parameter of the position and posture between two omnidirectional cameras simultaneously. The algorithm proposed in this paper extended Nonlinear Transformation (NLT) Method. This paper conducted the simulation experiment to check the validity of the proposed algorithm. In some simulation experiments, one mobile robot moves and observes the circumference of another mobile robot which has stopped at a certain place. This paper verified whether the mobile robot can estimate position using the measurement value when the number of observation times becomes 10 times in n/18 of observation intervals. The result of the simulation shows the effectiveness of the algorithm.
基金supported by the The Ministry of Knowledge Economy,Koreaunder the ITRC(Information Technology Research Center)support program supervised by the NIPA(National IT Industry Promotion Agency)(NIPA-2009-(C1090-0902-0007))the Ministry of Culture,Sports,and Tourism,Korea,under the CTRC(CTRC)support program supervised by the KOCCA
文摘Recently the improved robot working in very various fields, many researchers are trying to develop the robot to help people in the service field. However people who meet a robot in the first time gen- erally get heterogeneous feeling. To resolve this, we suggest an inter- active game with robots to increase the friendliness. The game, called "Divi-Divi-Dip" with 3 different body poses, is first introduced in a Korean TV prgrmn. The robot is using the visionary technology to recognize the pose with camera for the interactive game.
文摘In order to precisely measure the diameters for obtaining the fineness of rolling raw silk, the physical features of raw silk are analyzed. By means of Fresnel principle, diffractions caused by different transparent raw silk filaments are analyzed and simulated. Image data of raw silk filament measured by digital CMOS camera are analyzed and processed for obtaining the precise diameters of the filamerit with the relative error of less than 1%. On the assumption of appropriate elliptic cross-section of the filament, the cross-section area is calculated as the fineness of the filament. Measurement experiments are carded out. Finally, some suggestions are proposed for photoelectric measuring the fineness of raw silk.
文摘The infrared camera is a curious object for the animals of Changtang.Often covered in camouflage or army green,it looks very"professional".But once I saw the photos they took,I knew the camouflage did not work at all.Most animals could see the cameras without any problem.Some of them showed various degrees of interest in the cameras,while others acted indifferently.To tell the truth,it is not easy to hide something in Changtang.
文摘Objective To analyze the clinical and ultrasonographic imaging features of intraductal papillary mutinous neoplasm (1PMN) of the pancreas. Methods Twelve patients with IPMN underwent surgery between May 2005 and December 2008, including 4 (33.3%) with adenoma and 8 (66.7%) with adenocarcinoma. IPMN was classified preoperatively into 3 types based on sonographic findings of different sites: main duct, branch duct, and combined type. All clinical presentations and ultrasonographic findings of those paticnts were reviewed and the correlation be- tween ultrasonographic hndings and histopathological results was analyzed. Results There were 9 men and 3 women with a mean age of 60.1±9.6 years (range, 32-73). OF all the 12 patients with IPMN, 9 (75.0%) had experienced some symptoms of epigastric discomfort and/or pain as cell as backache; 7 cases were with medical history of acute pancreatitis, 5 cases with diabetes, 4 cases with elevated CA19-9, and 2 cases with steatorrhea. All lesions of IPMN have been revealed by transabdominal ul- trasonography. The mean diameters of the lesions were 1.4±0.8 cm (range, 0.5-2.0) and 6.3±6.0 cm (range, 2.0-20.0) in adenomas and adenocarcinomas, respectively. And the mean diameters of the main duct in adelnomas and adenocarcinomas were 1.0±0.8 cm and 1.6±1.0 cm, respectively. Among the 4 adnomas, 3 (75.0%) cases were classified as branch type based on sonographic findings, and 2 were demonstrated as mural nodules in which no color signals was detected. Among the 8 adenocarcinomas, 5 (62.5%) cases were classifled as main duct type, and 3 (37.5%) as combined type. In 7 of the 8 adcnocarcinomas, mural nodules were detected within the dilated ducts or cysts of the lesions in which color flow signals were detected. Conclusions Transabdominal ultrasonography can reveal the pancreatic cystic lesions of IPMN as well as dilated pancreatic: ducts. Some characteristics should be noticed as suggesting the possibility of malignancy: clinical symptoms of pancreatic insufficiency, large tumor size, and mural nodules with color Doppler flow signals. Transabdominal ultrasonography could be a useful tool to help diagnose and make appropriate management of IPMN.
基金Supported by National Natural Science Foundation of China(81101034)
文摘GANGLIONEUROMA is considered as the most mature and noninvasive form of neuroblastic tumors. It derives from neural crest cells, and can arise from wherever sympathetic tissue exists, including neck, posterior mediastinum, adrenal gland, retroperitoneum and pelvis. The two most common locations for this tumor are retroperitoneum and posterior mediastinum; infrequently it occurs in the intracranial re-gion,2-8 with only three cases has been reported arising from trigeminal nerve.2-4 The current paper presents a 49-year-old male patient with a ganglioneuroma arising from right trigeminal ganglion and extending to the mid-dle-posterior cranial fossa. We summarized the clinical and diagnostic characteristics of this extremely rare tumor, in comparison with the three reported cases in literatures.