Background Image matching is crucial in numerous computer vision tasks such as 3D reconstruction and simultaneous visual localization and mapping.The accuracy of the matching significantly impacted subsequent studies....Background Image matching is crucial in numerous computer vision tasks such as 3D reconstruction and simultaneous visual localization and mapping.The accuracy of the matching significantly impacted subsequent studies.Because of their local similarity,when image pairs contain comparable patterns but feature pairs are positioned differently,incorrect recognition can occur as global motion consistency is disregarded.Methods This study proposes an image-matching filtering algorithm based on global motion consistency.It can be used as a subsequent matching filter for the initial matching results generated by other matching algorithms based on the principle of motion smoothness.A particular matching algorithm can first be used to perform the initial matching;then,the rotation and movement information of the global feature vectors are combined to effectively identify outlier matches.The principle is that if the matching result is accurate,the feature vectors formed by any matched point should have similar rotation angles and moving distances.Thus,global motion direction and global motion distance consistencies were used to reject outliers caused by similar patterns in different locations.Results Four datasets were used to test the effectiveness of the proposed method.Three datasets with similar patterns in different locations were used to test the results for similar images that could easily be incorrectly matched by other algorithms,and one commonly used dataset was used to test the results for the general image-matching problem.The experimental results suggest that the proposed method is more accurate than other state-of-the-art algorithms in identifying mismatches in the initial matching set.Conclusions The proposed outlier rejection matching method can significantly improve the matching accuracy for similar images with locally similar feature pairs in different locations and can provide more accurate matching results for subsequent computer vision tasks.展开更多
Objective. To explore an effective method of surgical management of craniopharyngioma. Subjects and methods. Fifty patients with craniopharyngioma had total andsubtotal tumor ectomy. There were 29 males and 21 females...Objective. To explore an effective method of surgical management of craniopharyngioma. Subjects and methods. Fifty patients with craniopharyngioma had total andsubtotal tumor ectomy. There were 29 males and 21 females, ranging in age from 15 to 56 years (mean 34.1 years). MR imaging showed that the tumors were locatedin the superior sellar region in 24 cases, in superior sella region and extended into the third ventricular floor in 19 cases, into parasella in 3 cases and down to intrasella in 4 cases. Complete cystic tumors were found in 5 cases, whilethe partial cystic tumor in 24 cases and complete solid tumors in 21 cases. Pterional approach was used in 48 patients and subfrontal approach in 2 patients. Great attention was paid to the preservation of the perforating arteries from thecarotid, posterior and anterior communicating and anterior choroidal arteries to the hypothalamic structures. The clinical outcome was evaluated according to the GOS scale.Results. Of the 50 patients surgically treated, 47 patients obtained total ectomy of the tumor and 3 patients with the secondary surgery had subtotal ectomy of the tumor. The pituitary stalk was preserved in 29(58%) patients, severed in 14 patients and unidentified in 7 patients. Forty-six patients regained a normal life; one patient needed assist in life. Of the 3 deaths, one patient died of diabetes insipidus, one of inhalation asphyxia, and another one of water and sodium disorders. Conclusion. Avoidance of the injury to the neural structures in the thirdventricular floor and preservation of the perforating arteries to hypothalamus are the key to achieve good surgical results in treating craniopharyngioma.展开更多
The effects of tourmaline on nitrogen removal performance and biofilm structures were comparatively investigated in two identical laboratory-scale sequencing batch biofilm reactors（SBBRs）（denoted SBBR1 and SBBR2） ...The effects of tourmaline on nitrogen removal performance and biofilm structures were comparatively investigated in two identical laboratory-scale sequencing batch biofilm reactors（SBBRs）（denoted SBBR1 and SBBR2） at different nitrogen loading rates（NLRs） varying from（0.24 ± 0.01） to（1.26 ± 0.02） g N/（L·day）. SBBR1 was operated in parallel with SBBR2, but SBBR1 was filled with polyurethane foam loaded tourmaline（TPU） carriers and another（SBBR2） filled with polyurethane foam（PU） carriers. Results obtained from this study showed that the excellent and stable performance of SBBR1 was obtained. Ammonia nitrogen removal and total nitrogen removal were higher in SBBR1 than that in SBBR2 with increase of NLR. At an NLR of（0.24 ± 0.01） g N/（L·day）, the majority of the spherical and elliptical bacteria were surrounded by the extracellular polymeric substance（EPS） and bacillus or filamentous bacteria in two SBBRs biofilms. When NLR increased to（1.26 ± 0.02） g N/（L·day）, the clusters were more obvious in the SBBR1 biofilm than that in the SBBR2 biofilm. Bacteria in SBBR1 were inclined to synthesis more EPS, and the formed EPS could protect the bacteria from free ammonia（FA） under extreme condition NLR（1.26 ± 0.02） g N/（L·day）. The results of polymerase chain reaction-denaturing gradient gel electrophoresis analysis showed that the microbial community similarity in SBBR2 decreased more obviously than that in SBBR1 with the increase of NLR, which the microbial community in SBBR1 was relatively stable.展开更多
A case study on the transport process of agricultural diffuse P-pollutants was conducted in an experimental watershed locating in the north bank of Yuqiao Reservoir during 2001 and 2002. It was found that diversified ...A case study on the transport process of agricultural diffuse P-pollutants was conducted in an experimental watershed locating in the north bank of Yuqiao Reservoir during 2001 and 2002. It was found that diversified artificial and natural buffer/detention landscape structures distributing along the ephemeral stream channel in this watershed played an important role of pollutants removal on downstream water quality, especially they have control effect on the diffuse P-pollutants transport process. Surface flow velocity was reduced sharply after passing through these structures. During continuous runoff events, the removal rate of TSS, TP, TDP, DRP by the whole system were 66.7%, 60.7%, 48.4%, and 43.3%, respectively. During discontinuous runoff events, removal rate of pollutants by the whole system was higher due to there was no or little surface water and pollutants exported from the watershed, of which removal rate of pollutants all exceeded 99%. The statistical analysis results of runoff events(n=8) indicated that dry pond was the steadiest structure for controlling diffuse P-pollutants export.展开更多
基金Supported by the Natural Science Foundation of China(62072388,62276146)the Industry Guidance Project Foundation of Science technology Bureau of Fujian province(2020H0047)+2 种基金the Natural Science Foundation of Science Technology Bureau of Fujian province(2019J01601)the Creation Fund project of Science Technology Bureau of Fujian province(JAT190596)Putian University Research Project(2022034)。
文摘Background Image matching is crucial in numerous computer vision tasks such as 3D reconstruction and simultaneous visual localization and mapping.The accuracy of the matching significantly impacted subsequent studies.Because of their local similarity,when image pairs contain comparable patterns but feature pairs are positioned differently,incorrect recognition can occur as global motion consistency is disregarded.Methods This study proposes an image-matching filtering algorithm based on global motion consistency.It can be used as a subsequent matching filter for the initial matching results generated by other matching algorithms based on the principle of motion smoothness.A particular matching algorithm can first be used to perform the initial matching;then,the rotation and movement information of the global feature vectors are combined to effectively identify outlier matches.The principle is that if the matching result is accurate,the feature vectors formed by any matched point should have similar rotation angles and moving distances.Thus,global motion direction and global motion distance consistencies were used to reject outliers caused by similar patterns in different locations.Results Four datasets were used to test the effectiveness of the proposed method.Three datasets with similar patterns in different locations were used to test the results for similar images that could easily be incorrectly matched by other algorithms,and one commonly used dataset was used to test the results for the general image-matching problem.The experimental results suggest that the proposed method is more accurate than other state-of-the-art algorithms in identifying mismatches in the initial matching set.Conclusions The proposed outlier rejection matching method can significantly improve the matching accuracy for similar images with locally similar feature pairs in different locations and can provide more accurate matching results for subsequent computer vision tasks.
文摘Objective. To explore an effective method of surgical management of craniopharyngioma. Subjects and methods. Fifty patients with craniopharyngioma had total andsubtotal tumor ectomy. There were 29 males and 21 females, ranging in age from 15 to 56 years (mean 34.1 years). MR imaging showed that the tumors were locatedin the superior sellar region in 24 cases, in superior sella region and extended into the third ventricular floor in 19 cases, into parasella in 3 cases and down to intrasella in 4 cases. Complete cystic tumors were found in 5 cases, whilethe partial cystic tumor in 24 cases and complete solid tumors in 21 cases. Pterional approach was used in 48 patients and subfrontal approach in 2 patients. Great attention was paid to the preservation of the perforating arteries from thecarotid, posterior and anterior communicating and anterior choroidal arteries to the hypothalamic structures. The clinical outcome was evaluated according to the GOS scale.Results. Of the 50 patients surgically treated, 47 patients obtained total ectomy of the tumor and 3 patients with the secondary surgery had subtotal ectomy of the tumor. The pituitary stalk was preserved in 29(58%) patients, severed in 14 patients and unidentified in 7 patients. Forty-six patients regained a normal life; one patient needed assist in life. Of the 3 deaths, one patient died of diabetes insipidus, one of inhalation asphyxia, and another one of water and sodium disorders. Conclusion. Avoidance of the injury to the neural structures in the thirdventricular floor and preservation of the perforating arteries to hypothalamus are the key to achieve good surgical results in treating craniopharyngioma.
基金supported by the Project of Nature Scientific Foundation of Heilongjiang Province (No. C2017037)the National Natural Science Foundation of China (No. 31501839)
文摘The effects of tourmaline on nitrogen removal performance and biofilm structures were comparatively investigated in two identical laboratory-scale sequencing batch biofilm reactors（SBBRs）（denoted SBBR1 and SBBR2） at different nitrogen loading rates（NLRs） varying from（0.24 ± 0.01） to（1.26 ± 0.02） g N/（L·day）. SBBR1 was operated in parallel with SBBR2, but SBBR1 was filled with polyurethane foam loaded tourmaline（TPU） carriers and another（SBBR2） filled with polyurethane foam（PU） carriers. Results obtained from this study showed that the excellent and stable performance of SBBR1 was obtained. Ammonia nitrogen removal and total nitrogen removal were higher in SBBR1 than that in SBBR2 with increase of NLR. At an NLR of（0.24 ± 0.01） g N/（L·day）, the majority of the spherical and elliptical bacteria were surrounded by the extracellular polymeric substance（EPS） and bacillus or filamentous bacteria in two SBBRs biofilms. When NLR increased to（1.26 ± 0.02） g N/（L·day）, the clusters were more obvious in the SBBR1 biofilm than that in the SBBR2 biofilm. Bacteria in SBBR1 were inclined to synthesis more EPS, and the formed EPS could protect the bacteria from free ammonia（FA） under extreme condition NLR（1.26 ± 0.02） g N/（L·day）. The results of polymerase chain reaction-denaturing gradient gel electrophoresis analysis showed that the microbial community similarity in SBBR2 decreased more obviously than that in SBBR1 with the increase of NLR, which the microbial community in SBBR1 was relatively stable.
文摘A case study on the transport process of agricultural diffuse P-pollutants was conducted in an experimental watershed locating in the north bank of Yuqiao Reservoir during 2001 and 2002. It was found that diversified artificial and natural buffer/detention landscape structures distributing along the ephemeral stream channel in this watershed played an important role of pollutants removal on downstream water quality, especially they have control effect on the diffuse P-pollutants transport process. Surface flow velocity was reduced sharply after passing through these structures. During continuous runoff events, the removal rate of TSS, TP, TDP, DRP by the whole system were 66.7%, 60.7%, 48.4%, and 43.3%, respectively. During discontinuous runoff events, removal rate of pollutants by the whole system was higher due to there was no or little surface water and pollutants exported from the watershed, of which removal rate of pollutants all exceeded 99%. The statistical analysis results of runoff events(n=8) indicated that dry pond was the steadiest structure for controlling diffuse P-pollutants export.
