BACKGROUND Anesthetic drugs used in labor analgesia also paralyze the bladder muscle by blocking the sacral plexus,thereby affecting maternal postpartum spontaneous urination and increasing the risk of postpartum urin...BACKGROUND Anesthetic drugs used in labor analgesia also paralyze the bladder muscle by blocking the sacral plexus,thereby affecting maternal postpartum spontaneous urination and increasing the risk of postpartum urinary retention(PUR).AIM To analyze the effect of percutaneous electrical stimulation at the Baliao point combined with biofeedback therapy for PUR prevention.METHODS We selected 182 pregnant women who received labor analgesia in obstetrics between June 2022 and December 2023.They were divided into the combined therapy group(transcutaneous electrical stimulation of the Baliao point combined with biofeedback therapy)and the control group(biofeedback therapy alone).The first spontaneous urination time,first postpartum urine volume,bladder residual urine volume,postpartum hemorrhage volume,pre-urination waiting time,PUR incidence,adverse reactions,and the intervention’s clinical efficacy were compared between the two groups.RESULTS The first spontaneous urination time after delivery was more delayed(2.92±1.04 h vs 3.61±1.13 h,P<0.001),with fewer initial postpartum urine(163.54±24.67 mL vs 143.72±23.95 mL,P<0.001),more residual bladder urine(54.81±10.78 mL vs 65.25±13.52 mL,P<0.001),more postpartum bleeding(323.15±46.95 mL vs 348.12±45.03 mL,P=0.001),and longer waiting time for urination(0.94±0.31 min vs 1.29±0.42 min,P<0.001),in the control group than in the combined therapy group.The control group also had higher PUR incidence(4.65%vs 15.85%,P=0.016).Both groups had no adverse reactions,but the clinical total efficacy rate of the intervention was significantly higher in the combined therapy group than in the control group(95.35%vs 84.15%,P=0.016).CONCLUSION Percutaneous electrical stimulation of the Baliao point combined with biofeedback can significantly promote postpartum micturition of parturients with labor analgesia,thereby effectively preventing PUR occurrence.展开更多
Objective: To explore the effect of catgut implantation at Baliao and Xingfu One Acupuncture point for patients with urinary incontinence secondary to spinal cord injury (SCI). Methods: Three SCI patients received cat...Objective: To explore the effect of catgut implantation at Baliao and Xingfu One Acupuncture point for patients with urinary incontinence secondary to spinal cord injury (SCI). Methods: Three SCI patients received catgut embedding at Baliao and Xingfu One Acupuncture point. The data of intermittent catheterization (IC) volume, intermittent catheterization frequency and the amount of using urine pad (urethral condom) were corrected. Results: Compared to the baseline data, IC volume increased and the leakage volume decreased. Conclusions: Catgut Implantation at Baliao and Xingfu One Acupuncture point is effective for patients with urinary incontinence secondary to incomplete SCI.展开更多
<strong>Objective:</strong> To probe into the effect of catgut implantation at Baliao and Xingfu One Acupuncture Point on dysdefecation in patients with incomplete spinal cord injury (SCI). <strong>M...<strong>Objective:</strong> To probe into the effect of catgut implantation at Baliao and Xingfu One Acupuncture Point on dysdefecation in patients with incomplete spinal cord injury (SCI). <strong>Methods:</strong> Three SCI patients voluntarily accepted catgut embedding at Baliao and Xingfu One Acupuncture point. Before and after treatment, they were filled out the self-rating scale of defecation, including the data of defecation frequency, total defecation time, defecation effort, fecal texture, fecal characteristics and fecal incontinence, etc. <strong>Results:</strong> Compared with the baseline data, constipation was improved and fecal incontinence was disappeared. <strong>Conclusions:</strong> Catgut implantation at Baliao and Xingfu One Acupuncture Point is effectual for patients with neurogenic dysporia secondary to incomplete SCI.展开更多
Urinary retention after surgery is caused by inadvertent damage to the muscles and nerves around the bladder during the operation,which results in the suppression of the urination reflex,or the postoperative pain that...Urinary retention after surgery is caused by inadvertent damage to the muscles and nerves around the bladder during the operation,which results in the suppression of the urination reflex,or the postoperative pain that causes sphincter spasm and dysuria.It is a common complication after anorectal disease,with an incidence rate of up to 52%,which seriously affects the daily life of patients.It has been clinically discovered that acupuncture at Xinbaliao point can effectively improve urinary retention,relieve swelling in the lower abdomen,and improve the quality of life of patients.In this report,we present a case of postoperative urinary retention that had been treated with acupuncture at the Xinbaliao point.展开更多
Objective:To observe the clinical efficacy of Tuina(Chinese therapeutic massage),basically Yi Zhi Chan pushing at Baliao points in the treatment of functional constipation in infants and children aged 1-3 years old.Me...Objective:To observe the clinical efficacy of Tuina(Chinese therapeutic massage),basically Yi Zhi Chan pushing at Baliao points in the treatment of functional constipation in infants and children aged 1-3 years old.Methods:Seventy kids were randomly divided into an observation group and a control group,with 35 cases in each group.The control group was treated with conventional Tuina manipulation,while the observation group was treated with Tuina manipulation based on Yi Zhi Chan pushing at Baliao points.Both groups were treated once every other day,with 10 times as 1 course of treatment.The score on the self-developed constipation rating scale and clinical efficacy were compared after 1 course of treatment.Results:The total effective rate was 90.6%in the observation group and 76.7%in the control group,and the difference between the two groups was statistically significant(P<0.05).The degree of defecation difficulty in the children in the observation group was milder than that in the control group(P<0.01).Conclusion:Tuina manipulation based on Yi Zhi Chan pushing at Baliao points can significantly improve the degree of defecation difficulty in children,and the total effective rate is better than that of conventional Tuina manipulation.展开更多
Using angle-resolved photoemission spectroscopy and density functional theory calculations methods,we investigate the electronic structures and topological properties of ternary tellurides NbIrTe_(4),a candidate for t...Using angle-resolved photoemission spectroscopy and density functional theory calculations methods,we investigate the electronic structures and topological properties of ternary tellurides NbIrTe_(4),a candidate for type-II Weyl semimetal.We demonstrate the presence of several Fermi arcs connecting their corresponding Weyl points on both termination surfaces of the topological material.Our analysis reveals the existence of Dirac points,in addition to Weyl points,giving both theoretical and experimental evidences of the coexistence of Dirac and Weyl points in a single material.These findings not only confirm NbIrTe_(4) as a unique topological semimetal but also open avenues for exploring novel electronic devices based on its coexisting Dirac and Weyl fermions.展开更多
Internet Exchange Point(IXP)is a system that increases network bandwidth performance.Internet exchange points facilitate interconnection among network providers,including Internet Service Providers(ISPs)andContent Del...Internet Exchange Point(IXP)is a system that increases network bandwidth performance.Internet exchange points facilitate interconnection among network providers,including Internet Service Providers(ISPs)andContent Delivery Providers(CDNs).To improve service management,Internet exchange point providers have adopted the Software Defined Network(SDN)paradigm.This implementation is known as a Software-Defined Exchange Point(SDX).It improves network providers’operations and management.However,performance issues still exist,particularly with multi-hop topologies.These issues include switch memory costs,packet processing latency,and link failure recovery delays.The paper proposes Enhanced Link Failure Rerouting(ELFR),an improved mechanism for rerouting link failures in software-defined exchange point networks.The proposed mechanism aims to minimize packet processing time for fast link failure recovery and enhance path calculation efficiency while reducing switch storage overhead by exploiting the Programming Protocol-independent Packet Processors(P4)features.The paper presents the proposed mechanisms’efficiency by utilizing advanced algorithms and demonstrating improved performance in packet processing speed,path calculation effectiveness,and switch storage management compared to current mechanisms.The proposed mechanism shows significant improvements,leading to a 37.5%decrease in Recovery Time(RT)and a 33.33%decrease in both Calculation Time(CT)and Computational Overhead(CO)when compared to current mechanisms.The study highlights the effectiveness and resource efficiency of the proposed mechanism in effectively resolving crucial issues inmulti-hop software-defined exchange point networks.展开更多
Condensed state physics demonstrates that the Curie temperature is the point at which spontaneous magnetization drops to zero, marking the critical transition where ferromagnetic or ferrimagnetic materials transform i...Condensed state physics demonstrates that the Curie temperature is the point at which spontaneous magnetization drops to zero, marking the critical transition where ferromagnetic or ferrimagnetic materials transform into paramagnetic substances. Below the Curie temperature, a material remains ferromagnetic;above it, the material becomes paramagnetic, with its magnetic field easily influenced by external magnetic fileds. For example, the Curie temperature of iron (Fe) is 1043 K, while that of neodymium magnets ranges from 583 to 673 K. From both physics and mathematics perspectives, examining the temperature properties of materials is essential, as it provides valuable insights into their electromagnetic and thermodynamic behaviors. This paper makes a bold assumption and, for the first time, carefully verifies the existence of a Casimir temperature at 0.00206 K under conditions of one-atomic spacing.展开更多
In this paper, the dynamic properties of a discrete predator-prey model are discussed. The properties of non-hyperbolic fixed points and hyperbolic fixed points of the model are analyzed. First, by using the classic S...In this paper, the dynamic properties of a discrete predator-prey model are discussed. The properties of non-hyperbolic fixed points and hyperbolic fixed points of the model are analyzed. First, by using the classic Shengjin formula, we find the existence conditions for fixed points of the model. Then, by using the qualitative theory of ordinary differential equations and matrix theory we indicate which points are hyperbolic and which are non-hyperbolic and the associated conditions.展开更多
BACKGROUND Non-proliferative diabetic retinopathy(NPDR)poses a significant challenge in diabetes management due to its microvascular changes in the retina.Laser photocoagulation,a conventional therapy,aims to mitigate...BACKGROUND Non-proliferative diabetic retinopathy(NPDR)poses a significant challenge in diabetes management due to its microvascular changes in the retina.Laser photocoagulation,a conventional therapy,aims to mitigate the risk of progressing to proliferative diabetic retinopathy(PDR).AIM To compare the efficacy and safety of multi-spot vs single-spot scanning panretinal laser photocoagulation in NPDR patients.METHODS Forty-nine NPDR patients(86 eyes)treated between September 2020 and July 2022 were included.They were randomly allocated into single-spot(n=23,40 eyes)and multi-spot(n=26,46 eyes)groups.Treatment outcomes,including bestcorrected visual acuity(BCVA),central macular thickness(CMT),and mean threshold sensitivity,were assessed at predetermined intervals over 12 months.Adverse reactions were also recorded.RESULTS Energy levels did not significantly differ between groups(P>0.05),but the multi-spot group exhibited lower energy density(P<0.05).BCVA and CMT improvements were noted in the multi-spot group at one-month posttreatment(P<0.05).Adverse reaction incidence was similar between groups(P>0.05).CONCLUSION While energy intensity and safety were comparable between modalities,multi-spot scanning demonstrated lower energy density and showed superior short-term improvements in BCVA and CMT for NPDR patients,with reduced laser-induced damage.展开更多
To address the current issues of inaccurate segmentation and the limited applicability of segmentation methods for building facades in point clouds, we propose a facade segmentation algorithm based on optimal dual-sca...To address the current issues of inaccurate segmentation and the limited applicability of segmentation methods for building facades in point clouds, we propose a facade segmentation algorithm based on optimal dual-scale feature descriptors. First, we select the optimal dual-scale descriptors from a range of feature descriptors. Next, we segment the facade according to the threshold value of the chosen optimal dual-scale descriptors. Finally, we use RANSAC (Random Sample Consensus) to fit the segmented surface and optimize the fitting result. Experimental results show that, compared to commonly used facade segmentation algorithms, the proposed method yields more accurate segmentation results, providing a robust data foundation for subsequent 3D model reconstruction of buildings.展开更多
This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones a...This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique.展开更多
Recently, there have been some attempts of Transformer in 3D point cloud classification. In order to reduce computations, most existing methods focus on local spatial attention,but ignore their content and fail to est...Recently, there have been some attempts of Transformer in 3D point cloud classification. In order to reduce computations, most existing methods focus on local spatial attention,but ignore their content and fail to establish relationships between distant but relevant points. To overcome the limitation of local spatial attention, we propose a point content-based Transformer architecture, called PointConT for short. It exploits the locality of points in the feature space(content-based), which clusters the sampled points with similar features into the same class and computes the self-attention within each class, thus enabling an effective trade-off between capturing long-range dependencies and computational complexity. We further introduce an inception feature aggregator for point cloud classification, which uses parallel structures to aggregate high-frequency and low-frequency information in each branch separately. Extensive experiments show that our PointConT model achieves a remarkable performance on point cloud shape classification. Especially, our method exhibits 90.3% Top-1 accuracy on the hardest setting of ScanObjectN N. Source code of this paper is available at https://github.com/yahuiliu99/PointC onT.展开更多
The material point method(MPM)has been gaining increasing popularity as an appropriate approach to the solution of coupled hydro-mechanical problems involving large deformation.In this paper,we survey the current stat...The material point method(MPM)has been gaining increasing popularity as an appropriate approach to the solution of coupled hydro-mechanical problems involving large deformation.In this paper,we survey the current state-of-the-art in the MPM simulation of hydro-mechanical behaviour in two-phase porous geomaterials.The review covers the recent advances and developments in the MPM and their extensions to capture the coupled hydro-mechanical problems involving large deformations.The focus of this review is aiming at providing a clear picture of what has or has not been developed or implemented for simulating two-phase coupled large deformation problems,which will provide some direct reference for both practitioners and researchers.展开更多
Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ...Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ice class often navigate in channels opened up by icebreakers.Navigation in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large extent.The ship may get stuck if steered into ice fields off the channel.Under this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable method.In this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point regression.The first stage employs the image segmentation method to extract channel regions.In the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression network.The training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel dataset.The evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.展开更多
Cultural relics line graphic serves as a crucial form of traditional artifact information documentation,which is a simple and intuitive product with low cost of displaying compared with 3D models.Dimensionality reduct...Cultural relics line graphic serves as a crucial form of traditional artifact information documentation,which is a simple and intuitive product with low cost of displaying compared with 3D models.Dimensionality reduction is undoubtedly necessary for line drawings.However,most existing methods for artifact drawing rely on the principles of orthographic projection that always cannot avoid angle occlusion and data overlapping while the surface of cultural relics is complex.Therefore,conformal mapping was introduced as a dimensionality reduction way to compensate for the limitation of orthographic projection.Based on the given criteria for assessing surface complexity,this paper proposed a three-dimensional feature guideline extraction method for complex cultural relic surfaces.A 2D and 3D combined factor that measured the importance of points on describing surface features,vertex weight,was designed.Then the selection threshold for feature guideline extraction was determined based on the differences between vertex weight and shape index distributions.The feasibility and stability were verified through experiments conducted on real cultural relic surface data.Results demonstrated the ability of the method to address the challenges associated with the automatic generation of line drawings for complex surfaces.The extraction method and the obtained results will be useful for line graphic drawing,displaying and propaganda of cultural relics.展开更多
We present an application of short-pulse laser-generated hard x rays for the diagnosis of indirectly driven double shell targets. Coneinserted double shell targets were imploded through an indirect drive approach on t...We present an application of short-pulse laser-generated hard x rays for the diagnosis of indirectly driven double shell targets. Coneinserted double shell targets were imploded through an indirect drive approach on the upgraded SG-II laser facility. Then, based on thepoint-projection hard x-ray radiography technique, time-resolved radiography of the double shell targets, including that of their near-peakcompression, were obtained. The backlighter source was created by the interactions of a high-intensity short pulsed laser with a metalmicrowire target. Images of the target near peak compression were obtained with an Au microwire. In addition, radiation hydrodynamicsimulations were performed, and the target evolution obtained agrees well with the experimental results. Using the radiographic images, arealdensities of the targets were evaluated.展开更多
文摘BACKGROUND Anesthetic drugs used in labor analgesia also paralyze the bladder muscle by blocking the sacral plexus,thereby affecting maternal postpartum spontaneous urination and increasing the risk of postpartum urinary retention(PUR).AIM To analyze the effect of percutaneous electrical stimulation at the Baliao point combined with biofeedback therapy for PUR prevention.METHODS We selected 182 pregnant women who received labor analgesia in obstetrics between June 2022 and December 2023.They were divided into the combined therapy group(transcutaneous electrical stimulation of the Baliao point combined with biofeedback therapy)and the control group(biofeedback therapy alone).The first spontaneous urination time,first postpartum urine volume,bladder residual urine volume,postpartum hemorrhage volume,pre-urination waiting time,PUR incidence,adverse reactions,and the intervention’s clinical efficacy were compared between the two groups.RESULTS The first spontaneous urination time after delivery was more delayed(2.92±1.04 h vs 3.61±1.13 h,P<0.001),with fewer initial postpartum urine(163.54±24.67 mL vs 143.72±23.95 mL,P<0.001),more residual bladder urine(54.81±10.78 mL vs 65.25±13.52 mL,P<0.001),more postpartum bleeding(323.15±46.95 mL vs 348.12±45.03 mL,P=0.001),and longer waiting time for urination(0.94±0.31 min vs 1.29±0.42 min,P<0.001),in the control group than in the combined therapy group.The control group also had higher PUR incidence(4.65%vs 15.85%,P=0.016).Both groups had no adverse reactions,but the clinical total efficacy rate of the intervention was significantly higher in the combined therapy group than in the control group(95.35%vs 84.15%,P=0.016).CONCLUSION Percutaneous electrical stimulation of the Baliao point combined with biofeedback can significantly promote postpartum micturition of parturients with labor analgesia,thereby effectively preventing PUR occurrence.
文摘Objective: To explore the effect of catgut implantation at Baliao and Xingfu One Acupuncture point for patients with urinary incontinence secondary to spinal cord injury (SCI). Methods: Three SCI patients received catgut embedding at Baliao and Xingfu One Acupuncture point. The data of intermittent catheterization (IC) volume, intermittent catheterization frequency and the amount of using urine pad (urethral condom) were corrected. Results: Compared to the baseline data, IC volume increased and the leakage volume decreased. Conclusions: Catgut Implantation at Baliao and Xingfu One Acupuncture point is effective for patients with urinary incontinence secondary to incomplete SCI.
文摘<strong>Objective:</strong> To probe into the effect of catgut implantation at Baliao and Xingfu One Acupuncture Point on dysdefecation in patients with incomplete spinal cord injury (SCI). <strong>Methods:</strong> Three SCI patients voluntarily accepted catgut embedding at Baliao and Xingfu One Acupuncture point. Before and after treatment, they were filled out the self-rating scale of defecation, including the data of defecation frequency, total defecation time, defecation effort, fecal texture, fecal characteristics and fecal incontinence, etc. <strong>Results:</strong> Compared with the baseline data, constipation was improved and fecal incontinence was disappeared. <strong>Conclusions:</strong> Catgut implantation at Baliao and Xingfu One Acupuncture Point is effectual for patients with neurogenic dysporia secondary to incomplete SCI.
文摘Urinary retention after surgery is caused by inadvertent damage to the muscles and nerves around the bladder during the operation,which results in the suppression of the urination reflex,or the postoperative pain that causes sphincter spasm and dysuria.It is a common complication after anorectal disease,with an incidence rate of up to 52%,which seriously affects the daily life of patients.It has been clinically discovered that acupuncture at Xinbaliao point can effectively improve urinary retention,relieve swelling in the lower abdomen,and improve the quality of life of patients.In this report,we present a case of postoperative urinary retention that had been treated with acupuncture at the Xinbaliao point.
文摘Objective:To observe the clinical efficacy of Tuina(Chinese therapeutic massage),basically Yi Zhi Chan pushing at Baliao points in the treatment of functional constipation in infants and children aged 1-3 years old.Methods:Seventy kids were randomly divided into an observation group and a control group,with 35 cases in each group.The control group was treated with conventional Tuina manipulation,while the observation group was treated with Tuina manipulation based on Yi Zhi Chan pushing at Baliao points.Both groups were treated once every other day,with 10 times as 1 course of treatment.The score on the self-developed constipation rating scale and clinical efficacy were compared after 1 course of treatment.Results:The total effective rate was 90.6%in the observation group and 76.7%in the control group,and the difference between the two groups was statistically significant(P<0.05).The degree of defecation difficulty in the children in the observation group was milder than that in the control group(P<0.01).Conclusion:Tuina manipulation based on Yi Zhi Chan pushing at Baliao points can significantly improve the degree of defecation difficulty in children,and the total effective rate is better than that of conventional Tuina manipulation.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.12274455,12274459,and 12204533)the National Key R&D Program of China (Grant No.2022YFA1403800)the Beijing Natural Science Foundation (Grant No.Z200005)。
文摘Using angle-resolved photoemission spectroscopy and density functional theory calculations methods,we investigate the electronic structures and topological properties of ternary tellurides NbIrTe_(4),a candidate for type-II Weyl semimetal.We demonstrate the presence of several Fermi arcs connecting their corresponding Weyl points on both termination surfaces of the topological material.Our analysis reveals the existence of Dirac points,in addition to Weyl points,giving both theoretical and experimental evidences of the coexistence of Dirac and Weyl points in a single material.These findings not only confirm NbIrTe_(4) as a unique topological semimetal but also open avenues for exploring novel electronic devices based on its coexisting Dirac and Weyl fermions.
文摘Internet Exchange Point(IXP)is a system that increases network bandwidth performance.Internet exchange points facilitate interconnection among network providers,including Internet Service Providers(ISPs)andContent Delivery Providers(CDNs).To improve service management,Internet exchange point providers have adopted the Software Defined Network(SDN)paradigm.This implementation is known as a Software-Defined Exchange Point(SDX).It improves network providers’operations and management.However,performance issues still exist,particularly with multi-hop topologies.These issues include switch memory costs,packet processing latency,and link failure recovery delays.The paper proposes Enhanced Link Failure Rerouting(ELFR),an improved mechanism for rerouting link failures in software-defined exchange point networks.The proposed mechanism aims to minimize packet processing time for fast link failure recovery and enhance path calculation efficiency while reducing switch storage overhead by exploiting the Programming Protocol-independent Packet Processors(P4)features.The paper presents the proposed mechanisms’efficiency by utilizing advanced algorithms and demonstrating improved performance in packet processing speed,path calculation effectiveness,and switch storage management compared to current mechanisms.The proposed mechanism shows significant improvements,leading to a 37.5%decrease in Recovery Time(RT)and a 33.33%decrease in both Calculation Time(CT)and Computational Overhead(CO)when compared to current mechanisms.The study highlights the effectiveness and resource efficiency of the proposed mechanism in effectively resolving crucial issues inmulti-hop software-defined exchange point networks.
文摘Condensed state physics demonstrates that the Curie temperature is the point at which spontaneous magnetization drops to zero, marking the critical transition where ferromagnetic or ferrimagnetic materials transform into paramagnetic substances. Below the Curie temperature, a material remains ferromagnetic;above it, the material becomes paramagnetic, with its magnetic field easily influenced by external magnetic fileds. For example, the Curie temperature of iron (Fe) is 1043 K, while that of neodymium magnets ranges from 583 to 673 K. From both physics and mathematics perspectives, examining the temperature properties of materials is essential, as it provides valuable insights into their electromagnetic and thermodynamic behaviors. This paper makes a bold assumption and, for the first time, carefully verifies the existence of a Casimir temperature at 0.00206 K under conditions of one-atomic spacing.
文摘In this paper, the dynamic properties of a discrete predator-prey model are discussed. The properties of non-hyperbolic fixed points and hyperbolic fixed points of the model are analyzed. First, by using the classic Shengjin formula, we find the existence conditions for fixed points of the model. Then, by using the qualitative theory of ordinary differential equations and matrix theory we indicate which points are hyperbolic and which are non-hyperbolic and the associated conditions.
文摘BACKGROUND Non-proliferative diabetic retinopathy(NPDR)poses a significant challenge in diabetes management due to its microvascular changes in the retina.Laser photocoagulation,a conventional therapy,aims to mitigate the risk of progressing to proliferative diabetic retinopathy(PDR).AIM To compare the efficacy and safety of multi-spot vs single-spot scanning panretinal laser photocoagulation in NPDR patients.METHODS Forty-nine NPDR patients(86 eyes)treated between September 2020 and July 2022 were included.They were randomly allocated into single-spot(n=23,40 eyes)and multi-spot(n=26,46 eyes)groups.Treatment outcomes,including bestcorrected visual acuity(BCVA),central macular thickness(CMT),and mean threshold sensitivity,were assessed at predetermined intervals over 12 months.Adverse reactions were also recorded.RESULTS Energy levels did not significantly differ between groups(P>0.05),but the multi-spot group exhibited lower energy density(P<0.05).BCVA and CMT improvements were noted in the multi-spot group at one-month posttreatment(P<0.05).Adverse reaction incidence was similar between groups(P>0.05).CONCLUSION While energy intensity and safety were comparable between modalities,multi-spot scanning demonstrated lower energy density and showed superior short-term improvements in BCVA and CMT for NPDR patients,with reduced laser-induced damage.
文摘To address the current issues of inaccurate segmentation and the limited applicability of segmentation methods for building facades in point clouds, we propose a facade segmentation algorithm based on optimal dual-scale feature descriptors. First, we select the optimal dual-scale descriptors from a range of feature descriptors. Next, we segment the facade according to the threshold value of the chosen optimal dual-scale descriptors. Finally, we use RANSAC (Random Sample Consensus) to fit the segmented surface and optimize the fitting result. Experimental results show that, compared to commonly used facade segmentation algorithms, the proposed method yields more accurate segmentation results, providing a robust data foundation for subsequent 3D model reconstruction of buildings.
文摘This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique.
基金supported in part by the Nationa Natural Science Foundation of China (61876011)the National Key Research and Development Program of China (2022YFB4703700)+1 种基金the Key Research and Development Program 2020 of Guangzhou (202007050002)the Key-Area Research and Development Program of Guangdong Province (2020B090921003)。
文摘Recently, there have been some attempts of Transformer in 3D point cloud classification. In order to reduce computations, most existing methods focus on local spatial attention,but ignore their content and fail to establish relationships between distant but relevant points. To overcome the limitation of local spatial attention, we propose a point content-based Transformer architecture, called PointConT for short. It exploits the locality of points in the feature space(content-based), which clusters the sampled points with similar features into the same class and computes the self-attention within each class, thus enabling an effective trade-off between capturing long-range dependencies and computational complexity. We further introduce an inception feature aggregator for point cloud classification, which uses parallel structures to aggregate high-frequency and low-frequency information in each branch separately. Extensive experiments show that our PointConT model achieves a remarkable performance on point cloud shape classification. Especially, our method exhibits 90.3% Top-1 accuracy on the hardest setting of ScanObjectN N. Source code of this paper is available at https://github.com/yahuiliu99/PointC onT.
基金The financial supports from National Outstanding Youth Science Fund Project of National Natural Science Foundation of China(Grant No.52022112)the International Postdoctoral Exchange Fellowship Program(Talent-Introduction Program,Grant No.YJ20220219)。
文摘The material point method(MPM)has been gaining increasing popularity as an appropriate approach to the solution of coupled hydro-mechanical problems involving large deformation.In this paper,we survey the current state-of-the-art in the MPM simulation of hydro-mechanical behaviour in two-phase porous geomaterials.The review covers the recent advances and developments in the MPM and their extensions to capture the coupled hydro-mechanical problems involving large deformations.The focus of this review is aiming at providing a clear picture of what has or has not been developed or implemented for simulating two-phase coupled large deformation problems,which will provide some direct reference for both practitioners and researchers.
基金financially supported by the National Key Research and Development Program(Grant No.2022YFE0107000)the General Projects of the National Natural Science Foundation of China(Grant No.52171259)the High-Tech Ship Research Project of the Ministry of Industry and Information Technology(Grant No.[2021]342)。
文摘Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ice class often navigate in channels opened up by icebreakers.Navigation in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large extent.The ship may get stuck if steered into ice fields off the channel.Under this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable method.In this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point regression.The first stage employs the image segmentation method to extract channel regions.In the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression network.The training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel dataset.The evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.
基金National Natural Science Foundation of China(Nos.42071444,42101444)。
文摘Cultural relics line graphic serves as a crucial form of traditional artifact information documentation,which is a simple and intuitive product with low cost of displaying compared with 3D models.Dimensionality reduction is undoubtedly necessary for line drawings.However,most existing methods for artifact drawing rely on the principles of orthographic projection that always cannot avoid angle occlusion and data overlapping while the surface of cultural relics is complex.Therefore,conformal mapping was introduced as a dimensionality reduction way to compensate for the limitation of orthographic projection.Based on the given criteria for assessing surface complexity,this paper proposed a three-dimensional feature guideline extraction method for complex cultural relic surfaces.A 2D and 3D combined factor that measured the importance of points on describing surface features,vertex weight,was designed.Then the selection threshold for feature guideline extraction was determined based on the differences between vertex weight and shape index distributions.The feasibility and stability were verified through experiments conducted on real cultural relic surface data.Results demonstrated the ability of the method to address the challenges associated with the automatic generation of line drawings for complex surfaces.The extraction method and the obtained results will be useful for line graphic drawing,displaying and propaganda of cultural relics.
基金supported by the National Key R&D Program of China(Grant Nos.2022YFA1603300 and 2022YFA1603200)the Science Challenge Project(Grant No.TZ2018005)in China+1 种基金the National Natural Science Foundation of China(Grant Nos.11805188 and 12175209)the Laser Fusion Research Center Funds for Young Talents(Grant No.RCFPD6-2022-1).
文摘We present an application of short-pulse laser-generated hard x rays for the diagnosis of indirectly driven double shell targets. Coneinserted double shell targets were imploded through an indirect drive approach on the upgraded SG-II laser facility. Then, based on thepoint-projection hard x-ray radiography technique, time-resolved radiography of the double shell targets, including that of their near-peakcompression, were obtained. The backlighter source was created by the interactions of a high-intensity short pulsed laser with a metalmicrowire target. Images of the target near peak compression were obtained with an Au microwire. In addition, radiation hydrodynamicsimulations were performed, and the target evolution obtained agrees well with the experimental results. Using the radiographic images, arealdensities of the targets were evaluated.