AIM： To evaluate the agreement between transrectal ultrasound （TRUS） and magnetic resonance imaging （MRI） in classification of ≥ T3 rectal tumors. METHODS： From January 2010 to January 2012, 86 consecutive pati...AIM： To evaluate the agreement between transrectal ultrasound （TRUS） and magnetic resonance imaging （MRI） in classification of ≥ T3 rectal tumors. METHODS： From January 2010 to January 2012, 86 consecutive patients with ≥ T3 tumors were included in this study. The mean age of the patients was 66.4 years （range： 26-91 years）. The tumors were all ≥ T3 on TRUS. The sub-classification was defined by the penetration of the rectal wall： a： 0 to 1 mm; b： 1-5 mm, c： 6-15; d： 〉 15 mm. Early tumors as ab （≤ 5 ram） and advanced tumors as cd （〉 5 mm）. All patients underwent TRUS using a 6.5 MHz transrectal transducer. The MRI was performed with a 1.5 T Phil- ips unit. The TRUS findings were blinded to the radiol- ogist performing the interpretation of the MRI images and measuring the depth of extramural tumor spread RESULTS： TRUS found 51 patients to have an early ≥ T3 tumors and 35 to have an advanced tumor, where- as MRI categorized 48 as early ≥ T3 tumors and 38 as advanced tumors. No patients with tumors classified as advanced by TRUS were found to be early on MRI. The kappa value in classifying early versus advanced T3 rectal tumors was 0.93 （95% CI： 0.85-1.00）. We found a kappa value of 0.74 （95% CI： 0.63-0.86） for the total sub-classification between the two methods. The mean maximal tumor outgrowth measured by TRUS, 5.5 mm ± 5.63 mm and on MRI, 6.3 mm ±6.18 mm, P = 0.004. In 19 of the 86 patients the following CT scan or surgery revealed distant metastases; of the 51 patients in the ultrasound ab group three （5.9%） had metastases, whereas 16 （45.7%） of 35 in the cd group harbored distant metastases, P = 0.00002. The odds ratio of having distant metastases in the ultra- sound cd group compared to the ab group was 13.5 （95% CI： 3.5-51.6）, P = 0.00002. The mean maximal ultrasound measured outgrowth was 4.3 mm （95% CI： 3.2-5.5 mm） in patients without distant metastases, while the mean maximal outgrowth was 9.5 mm （95% CI： 6.2-12.8 ram） in the patients with metastases, P = 0.00004. Using the MRI classification three （6.3%） of 48 in the MRI ab group had distant metastases, while 16 （42.1%） of the 38 in the MRI cd group, P = 0.00004. The MRI odds ratio was 10.9 （95% CI： 2.9-41.4）, P = 0.00008. The mean maximal MRI measured out- growth was 4.9 mm （95% CI： 3.7-6.1 turn） in patients without distant metastases, while the mean maximal outgrowth was 11.5 mm （95% CI： 7.8-15.2 mm） in the patients with metastases, P = 0.000006. CONCLUSION： There is good agreement between TRUS and MRI in the pretreatment sub-classification of ≥ T3 tumors. Distant metastases are more frequent in the advanced group.展开更多
Since there is lack of methodology to assess the performance of defogging algorithm and the existing assessment methods have some limitations,three new methods for assessing the defogging algorithm were proposed.One w...Since there is lack of methodology to assess the performance of defogging algorithm and the existing assessment methods have some limitations,three new methods for assessing the defogging algorithm were proposed.One was using synthetic foggy image simulated by image degradation model to assess the defogging algorithm in full-reference way.In this method,the absolute difference was computed between the synthetic image with and without fog.The other two were computing the fog density of gray level image or constructing assessment system of color image from human visual perception to assess the defogging algorithm in no-reference way.For these methods,an assessment function was defined to evaluate algorithm performance from the function value.Using the defogging algorithm comparison,the experimental results demonstrate the effectiveness and reliability of the proposed methods.展开更多
A self-developed laser image measurement system was established to study the behavior of bubble for- mation at a single orifice in non-Newtonian polyacrylamide(PAAm)solutions.Images of bubbles were captured by a CCD c...A self-developed laser image measurement system was established to study the behavior of bubble for- mation at a single orifice in non-Newtonian polyacrylamide(PAAm)solutions.Images of bubbles were captured by a CCD camera and volumes of bubbles were digitally analyzed online.The effects of rheological property of PAAm solution,orifice,reservoir,and gas flowrate on bubble formation were studied experimentally.It is found that the volume of bubble increases with the concentration of PAAm solution,the diameter of the orifice,and the gas flowrate,respectively,whereas little effect of reservoir is observed in experiments.展开更多
Laser triangulation theory was used to develop a novel contact-free method for measuring the coal level in a silo under harsh environmental conditions found in coal mines, such as the presence of dense dust, high humi...Laser triangulation theory was used to develop a novel contact-free method for measuring the coal level in a silo under harsh environmental conditions found in coal mines, such as the presence of dense dust, high humidity, and low illumination. A laser source and a camera were mounted at the top of the silo. The laser spot projected into the silo was imaged by the camera. The pinhole imaging principle allows the level to be found from the lateral shift of the spot image on the sensor. A pre-calibrated look-up table of the coal depth versus spot position was used to obtain the depth. The measurement accuracy depends on the step size used during pre-calibration. The actual application of a device designed according to these principles shows that it is easy to implement. The detection of the coal level in a silo at the low illumination level found in coal mines is demonstrated.展开更多
To provide a realistic simulation environment for users,intelligent models have become key components in military simulations. After the analysis of modeling nature of intelligent models,the validation criteria for de...To provide a realistic simulation environment for users,intelligent models have become key components in military simulations. After the analysis of modeling nature of intelligent models,the validation criteria for defining the validation points and validation metrics for measuring the agreements between human experts and intelligent models were presented. Further,such methods as graphical comparison,feature analysis and face validation were discussed according to the characteristics of intelligent models. Based on the validation criteria,validation metrics and validation methods,the intelligent models can be effectively validated,which has been proved in current developed intelligent models.展开更多
为了更好地实施土地整治项目,为土地整治项目规划、设计、施工等环节高效成图、高精度制图提供新思路,客观探讨无人机内置RTK(Real Time Kinematic, RTK)航拍技术在土地整治项目区测绘成图及辅助规划设计中的应用价值,以江西省某县土地...为了更好地实施土地整治项目,为土地整治项目规划、设计、施工等环节高效成图、高精度制图提供新思路,客观探讨无人机内置RTK(Real Time Kinematic, RTK)航拍技术在土地整治项目区测绘成图及辅助规划设计中的应用价值,以江西省某县土地整治项目片区为研究区,通过作业过程中机身RTK实时接收基站的差分GPS修正数据实现定位坐标优化,选取航片上20个点平面坐标及其高程,与RTK地面实测检查点的平面坐标和高程进行中误差分析完成精度验证.研究结果发现:内置RTK无人机航拍的正射影像分辨率为0.033 m,其平面坐标中误差为0.051 m,数字高程模型高程中误差为0.070 m,精度结果满足土地整治项目测量成图相关精度要求.此外,文章进一步探讨该技术及相关数字产品在土方量计算、辅助规划设计等领域的应用情况.研究表明:该技术在土地整治项目应用中精度优势明显、可视化效果好,尤其对土方计算、规划设计、核查验收等环节具有较高的应用价值.展开更多
A new method for the retrieval of ocean wave parameters from SAR imagery is developed,based on the shape-from-shading(SFS)technique.Previously,the SFS technique has been used in the reconstruction of 3D landform infor...A new method for the retrieval of ocean wave parameters from SAR imagery is developed,based on the shape-from-shading(SFS)technique.Previously,the SFS technique has been used in the reconstruction of 3D landform information from SAR images,in order to generate elevation maps of topography for land surfaces.Here,in order to retrieve ocean wave characteristics,we apply the SFS methodology,together with a method to orient the angular measurements of the azimuth slope and range slope,in the measurement of ocean surface waves.This method is applied to high resolution fine-quad polarization mode(HH,VV,VH and HV)C-band RADARSAT-2 SAR imagery,in order to retrieve ocean wave spectra and extract wave parameters.Collocated in situ buoy measurements are used to validate the reliability of this method.Results show that the method can reliably estimate wave height,dominant wave period,dominant wave length and dominant wave direction from C-band SAR images.The advantage of this method is that it does not depend on modulation transfer functions(MTFs),in order to measure ocean surface waves.This method can be used in monitoring ocean surface wave propagation through open water areas into ice-covered areas,especially the marginal ice zone(MIZ)in polar oceans.展开更多
文摘AIM： To evaluate the agreement between transrectal ultrasound （TRUS） and magnetic resonance imaging （MRI） in classification of ≥ T3 rectal tumors. METHODS： From January 2010 to January 2012, 86 consecutive patients with ≥ T3 tumors were included in this study. The mean age of the patients was 66.4 years （range： 26-91 years）. The tumors were all ≥ T3 on TRUS. The sub-classification was defined by the penetration of the rectal wall： a： 0 to 1 mm; b： 1-5 mm, c： 6-15; d： 〉 15 mm. Early tumors as ab （≤ 5 ram） and advanced tumors as cd （〉 5 mm）. All patients underwent TRUS using a 6.5 MHz transrectal transducer. The MRI was performed with a 1.5 T Phil- ips unit. The TRUS findings were blinded to the radiol- ogist performing the interpretation of the MRI images and measuring the depth of extramural tumor spread RESULTS： TRUS found 51 patients to have an early ≥ T3 tumors and 35 to have an advanced tumor, where- as MRI categorized 48 as early ≥ T3 tumors and 38 as advanced tumors. No patients with tumors classified as advanced by TRUS were found to be early on MRI. The kappa value in classifying early versus advanced T3 rectal tumors was 0.93 （95% CI： 0.85-1.00）. We found a kappa value of 0.74 （95% CI： 0.63-0.86） for the total sub-classification between the two methods. The mean maximal tumor outgrowth measured by TRUS, 5.5 mm ± 5.63 mm and on MRI, 6.3 mm ±6.18 mm, P = 0.004. In 19 of the 86 patients the following CT scan or surgery revealed distant metastases; of the 51 patients in the ultrasound ab group three （5.9%） had metastases, whereas 16 （45.7%） of 35 in the cd group harbored distant metastases, P = 0.00002. The odds ratio of having distant metastases in the ultra- sound cd group compared to the ab group was 13.5 （95% CI： 3.5-51.6）, P = 0.00002. The mean maximal ultrasound measured outgrowth was 4.3 mm （95% CI： 3.2-5.5 mm） in patients without distant metastases, while the mean maximal outgrowth was 9.5 mm （95% CI： 6.2-12.8 ram） in the patients with metastases, P = 0.00004. Using the MRI classification three （6.3%） of 48 in the MRI ab group had distant metastases, while 16 （42.1%） of the 38 in the MRI cd group, P = 0.00004. The MRI odds ratio was 10.9 （95% CI： 2.9-41.4）, P = 0.00008. The mean maximal MRI measured out- growth was 4.9 mm （95% CI： 3.7-6.1 turn） in patients without distant metastases, while the mean maximal outgrowth was 11.5 mm （95% CI： 7.8-15.2 mm） in the patients with metastases, P = 0.000006. CONCLUSION： There is good agreement between TRUS and MRI in the pretreatment sub-classification of ≥ T3 tumors. Distant metastases are more frequent in the advanced group.
基金Projects(91220301,61175064,61273314)supported by the National Natural Science Foundation of ChinaProject(126648)supported by the Postdoctoral Science Foundation of Central South University,ChinaProject(2012170301)supported by the New Teacher Fund for School of Information Science and Engineering,Central South University,China
文摘Since there is lack of methodology to assess the performance of defogging algorithm and the existing assessment methods have some limitations,three new methods for assessing the defogging algorithm were proposed.One was using synthetic foggy image simulated by image degradation model to assess the defogging algorithm in full-reference way.In this method,the absolute difference was computed between the synthetic image with and without fog.The other two were computing the fog density of gray level image or constructing assessment system of color image from human visual perception to assess the defogging algorithm in no-reference way.For these methods,an assessment function was defined to evaluate algorithm performance from the function value.Using the defogging algorithm comparison,the experimental results demonstrate the effectiveness and reliability of the proposed methods.
基金Supported by the National Natural Science Foundation of China （No.20476073） and the Programs of Introducing Talents of Discipline to Universities （Grant No.B06006）.
文摘A self-developed laser image measurement system was established to study the behavior of bubble for- mation at a single orifice in non-Newtonian polyacrylamide(PAAm)solutions.Images of bubbles were captured by a CCD camera and volumes of bubbles were digitally analyzed online.The effects of rheological property of PAAm solution,orifice,reservoir,and gas flowrate on bubble formation were studied experimentally.It is found that the volume of bubble increases with the concentration of PAAm solution,the diameter of the orifice,and the gas flowrate,respectively,whereas little effect of reservoir is observed in experiments.
基金supported by the National Natural Science Foun-dation of China (No. 51074169)
文摘Laser triangulation theory was used to develop a novel contact-free method for measuring the coal level in a silo under harsh environmental conditions found in coal mines, such as the presence of dense dust, high humidity, and low illumination. A laser source and a camera were mounted at the top of the silo. The laser spot projected into the silo was imaged by the camera. The pinhole imaging principle allows the level to be found from the lateral shift of the spot image on the sensor. A pre-calibrated look-up table of the coal depth versus spot position was used to obtain the depth. The measurement accuracy depends on the step size used during pre-calibration. The actual application of a device designed according to these principles shows that it is easy to implement. The detection of the coal level in a silo at the low illumination level found in coal mines is demonstrated.
基金Sponsored by the National Natural Science Foundation of China(Grant No. 60434010)the Foundation of the Outstanding Youth of Heilongjiang Province ( Grant No. JC200606)
文摘To provide a realistic simulation environment for users,intelligent models have become key components in military simulations. After the analysis of modeling nature of intelligent models,the validation criteria for defining the validation points and validation metrics for measuring the agreements between human experts and intelligent models were presented. Further,such methods as graphical comparison,feature analysis and face validation were discussed according to the characteristics of intelligent models. Based on the validation criteria,validation metrics and validation methods,the intelligent models can be effectively validated,which has been proved in current developed intelligent models.
基金This work was supported by the National Natural Science Foundation of China(Grant NO.41276187)the Global Change Research Program of China(Grant No.2015CB953901)+3 种基金the Startup Foundation for Introducing Talent of NUIST(Grant No.20110310)Program for Innovation Research and Entrepreneurship Team in Jiangsu Provincethe CFOSAT project,the Canadian Program on Energy Research and Developmentthe Canadian Space Agency GRIP program funding for wave-ice interactions
文摘A new method for the retrieval of ocean wave parameters from SAR imagery is developed,based on the shape-from-shading(SFS)technique.Previously,the SFS technique has been used in the reconstruction of 3D landform information from SAR images,in order to generate elevation maps of topography for land surfaces.Here,in order to retrieve ocean wave characteristics,we apply the SFS methodology,together with a method to orient the angular measurements of the azimuth slope and range slope,in the measurement of ocean surface waves.This method is applied to high resolution fine-quad polarization mode(HH,VV,VH and HV)C-band RADARSAT-2 SAR imagery,in order to retrieve ocean wave spectra and extract wave parameters.Collocated in situ buoy measurements are used to validate the reliability of this method.Results show that the method can reliably estimate wave height,dominant wave period,dominant wave length and dominant wave direction from C-band SAR images.The advantage of this method is that it does not depend on modulation transfer functions(MTFs),in order to measure ocean surface waves.This method can be used in monitoring ocean surface wave propagation through open water areas into ice-covered areas,especially the marginal ice zone(MIZ)in polar oceans.
