Nosing process of circular metal tubes in empty and polyurethane foam-filled conditions on a semispherical rigid die was analyzed by theoretical and experimental methods.A new theoretical model of plastic deformation ...Nosing process of circular metal tubes in empty and polyurethane foam-filled conditions on a semispherical rigid die was analyzed by theoretical and experimental methods.A new theoretical model of plastic deformation of circular metal tubes was demonstrated during the nosing process on a rigid semispherical die.Based on the analytical model,some theoretical relations were calculated to estimate instantaneous forming load and dissipated energy of empty and foam-filled circular metal tubes versus axial displacement.Some circular brazen and aluminum tubes were prepared and shaped into semispherical nosed nozzles to verify the present theory.Comparison of theoretical predictions and the corresponding experimental measurements reveals that predicted load?displacement and dissipated energy?displacement diagrams by theoretical formulas have a good correlation with the corresponding experimental curves and it proves verity of the theory.Also,the present theory shows that dissipated energy and axial load of empty tubes depend on material type,wall thickness and diameter of the tubes and they are independent of tube initial length.Furthermore,the experimental results show that the presence of polyethylene Teflon-constraints increases ultimate axial displacement of the forming process.展开更多
Volatile organic compounds(VOCs) emitted from stool are the components of the smell of stool representing the end products of microbial activity and metabolism that can be used to diagnose disease. Despite the abundan...Volatile organic compounds(VOCs) emitted from stool are the components of the smell of stool representing the end products of microbial activity and metabolism that can be used to diagnose disease. Despite the abundance of hydrogen, carbon dioxide, and methane that have already been identified in human flatus, the small portion of trace gases making up the VOCs emitted from stool include organic acids, alcohols, esters, heterocyclic compounds, aldehydes, ketones, and alkanes, among others. These are the gases that vary among individuals in sickness and in health, in dietary changes, and in gut microbial activity. Electronic nose devices are analytical and pattern recognition platforms that can utilize mass spectrometry or electrochemical sensors to detect these VOCs in gas samples. When paired with machine-learning and pattern recognition algorithms, this can identify patterns of VOCs, and thus patterns of smell, that can be used to identify disease states. In this review, we provide a clinical background of VOC identification, electronic nose development, and review gastroenterology applications toward diagnosing disease by the volatile headspace analysis of stool.展开更多
Lung diseases pose a significant threat to public health worldwide,resulting in a substantial number of fatalities.Diseases such as chronic obstructive pulmonary disease and lung cancer constitute two of the three dea...Lung diseases pose a significant threat to public health worldwide,resulting in a substantial number of fatalities.Diseases such as chronic obstructive pulmonary disease and lung cancer constitute two of the three deadliest diseases worldwide,contributing to over 3 million deaths annually.This study offered a comparative analysis of different diagnostic techniques used for lung pathologies from an engineering standpoint.The review concentrated on intelligent detection methods,including electronic nose,computer vision(CV),or image processing,and biosensors such as graphene-field effect transistor(FET).The E-nose-based detection technique uses electronic sensors to recognize volatile organic compounds(VOCs)in the exhaled breath.These VOCs can aid in the diagnosis of lung pathologies such as pneumonia.The CV processing method involves the application of advanced imaging techniques and machine learning algorithms to scrutinize and diagnose lung pathologies and ventilatorassociated pneumonia(VAP).Lastly,biosensors employ the exceptional properties of these materials to identify specific biomarkers in biological samples.This information can be used to diagnose lung pathologies and VAP.This study examined the current state-of-the-art methods and offers a comprehensive analysis of their advantages and disadvantages from an engineering perspective.The study underscored the potential of these techniques to enhance the diagnosis of lung pathologies and VAP and presents the advances in the field of smart biomedical applications.Additionally,it emphasized the necessity for further research to optimize their performance and clinical usefulness.展开更多
Kong Weili is my classmate and she is my good friend,either①•She is thirteen years old this year.She isn’t very tall,and her eyes,nose and mouth are very small,but I think she looks very beautiful.
I love dogs because they are so friendly and lovely.With bright eyes,dogs can see things in the dark.Their noses are very sensitive,and this helps them find things easily.My pet dog is named Dahu.He is white with long...I love dogs because they are so friendly and lovely.With bright eyes,dogs can see things in the dark.Their noses are very sensitive,and this helps them find things easily.My pet dog is named Dahu.He is white with long ears.Every day when I come back home from school,he runs to me happily and wags his tail.We often play games together.He likes to chase a ball,and I throw the ball far,then he runs quickly to bring it back.展开更多
Climate change has prompted the aviation industry to reduce greenhouse gas emissions.Variable-camber leading edges,with their adaptable aerodynamic shapes,hold significant potential for laminar flow wings and contribu...Climate change has prompted the aviation industry to reduce greenhouse gas emissions.Variable-camber leading edges,with their adaptable aerodynamic shapes,hold significant potential for laminar flow wings and contribute to greener aviation.In response to this need,this paper proposes a design optimization method for a variable-camber leading edge featuring an outer variablethickness composite compliant skin and an inner open-kinematic-chain mechanism.The optimization methodology employs a fiber continuity model based on a ply-drop sequence,a guiding sequence and a thickness sequence to describe the variable-thickness composite compliant skin structure,enabling direct generation of a composite layup sequence that meets fiber continuity criteria.Additionally,the design methodology for the inner open kinematic chain considers the rigidflexible coupling effect and analyzes the number of driving ribs along the span-wise direction.Finally,a full-scale physical prototype for a large-scale civil aircraft is developed and experimented in the FL-10 wind tunnel,demonstrating that the variable-camber leading edge can smoothly and precisely achieve its target shape and hold its final profile under the corresponding aerodynamic loads,thereby validating the proposed design methodology.展开更多
The non-scaling effect on the penetration depth of rigid projectiles is an important issue that must be considered when extending the results of scaled experiments to prototype scenes.In this study,the evolution of th...The non-scaling effect on the penetration depth of rigid projectiles is an important issue that must be considered when extending the results of scaled experiments to prototype scenes.In this study,the evolution of the stress and strain of the target under penetration was analyzed.Expressions for the penetration resistance and penetration depth were obtained based on the conservation equation and continuity condition of the target.The penetration coefficients that characterize the nose shape,target resistance,and non-scaling effect were defined.Simplified calculation methods for the coefficients within the range of rigid projectile penetration were developed.Two methods for estimating the target parameters are proposed.The results show that the non-scaling effect is related to the failure process of the target and depends on the ratio of cavity radius to comminuted region radius.The nose shape coefficient can be approximated as a linear function of the length-to-diameter ratio of the nose.The noseshape coefficient of a flat-nosed projectile is 0.57.The caliber coefficient is related to the projectile diameter and reflects the non-scaling effect,which increases with the projectile diameter.A practical formula for calculating the penetration depth of rigid projectiles considering the non-scaling effect is also proposed.This formula is in good agreement with penetration experiments on rock and concrete.展开更多
Swing nose crossings(SNXs)have been widely used in heavy haul railways to create a smoother load transfer and hence reduced impact load.However,the current design of SNXs hasn’t been fully examined under heavy haul o...Swing nose crossings(SNXs)have been widely used in heavy haul railways to create a smoother load transfer and hence reduced impact load.However,the current design of SNXs hasn’t been fully examined under heavy haul operating conditions.Additionally,maintenance guidelines for SNX wear-related issues in Australian heavy haul railways are relatively lacking.As such,this study aims to investigate the dynamic response of the wheel-rail contact and analyse the wear performance of an SNX currently used in Australian heavy haul railways.Dynamic implicit-explicit finite element analysis was conducted to simulate the wheel-rail contact along the SNX.The distribution of the wear intensity over the SNX was identified by using a local contact-based wear model.The influence of various scenarios on wear was also explored.The results verify the improved dynamic performance of the SNX,as the increased contact force after load transfer remains below 1.2 times the static load.The findings also indicate that the decrease in relative height and increase in nose rail inclination result in greater wear on the nose rail.Notably,the SNX considered in the current study exhibits better wear performance when used with moderately worn wheels.展开更多
This paper presents a novel method for reconstructing a highly accurate 3D nose model of the human from 2D images and pre-marked landmarks based on algorithmic methods.The study focuses on the reconstruction of a 3D n...This paper presents a novel method for reconstructing a highly accurate 3D nose model of the human from 2D images and pre-marked landmarks based on algorithmic methods.The study focuses on the reconstruction of a 3D nose model tailored for applications in healthcare and cosmetic surgery.The approach leverages advanced image processing techniques,3D Morphable Models(3DMM),and deformation techniques to overcome the limita-tions of deep learning models,particularly addressing the interpretability issues commonly encountered in medical applications.The proposed method estimates the 3D coordinates of landmark points using a 3D structure estimation algorithm.Sub-landmarks are extracted through image processing techniques and interpolation.The initial surface is generated using a 3DMM,though its accuracy remains limited.To enhance precision,deformation techniques are applied,utilizing the coordinates of 76 identified landmarks and sub-landmarks.The resulting 3D nose model is constructed based on algorithmic methods and pre-marked landmarks.Evaluation of the 3D model is conducted by comparing landmark distances and shape similarity with expert-determined ground truth on 30 Vietnamese volunteers aged 18 to 47,all of whom were either preparing for or required nasal surgery.Experimental results demonstrate a strong agreement between the reconstructed 3D model and the ground truth.The method achieved a mean landmark distance error of 0.631 mm and a shape error of 1.738 mm,demonstrating its potential for medical applications.展开更多
经自然腔道取标本手术(Natural Orifice Specimen Extraction Surgery, NOSES)避免了腹壁的辅助切口,有极佳的微创效果。与传统腹腔镜手术相比,NOSES在确保彻底切除肿瘤的同时也最大限度地保留了腹壁原有的功能,规避了与腹壁切口相关的...经自然腔道取标本手术(Natural Orifice Specimen Extraction Surgery, NOSES)避免了腹壁的辅助切口,有极佳的微创效果。与传统腹腔镜手术相比,NOSES在确保彻底切除肿瘤的同时也最大限度地保留了腹壁原有的功能,规避了与腹壁切口相关的并发症,具有术后恢复快、疼痛轻、美容效果好以及术后并发症少等优点。文章综合分析了近年来有关文献的研究成果与报道,深入探讨了经自然腔道取标本手术(NOSES)在结直肠癌领域的发展历程、主要分类、适应症与禁忌症、优点与争议等方面,旨在为临床应用提供参考。Natural Orifice Specimen Extraction Surgery (NOSES) eliminates the need for auxiliary abdominal wall incisions, offering exceptional minimally invasive outcomes. Compared to traditional laparoscopic surgery, NOSES ensures complete tumor removal while preserving the abdominal wall’s natural function to the greatest extent, thus sidestepping complications linked to abdominal wall incisions. It boasts advantages such as swift postoperative recovery, minimal pain, excellent cosmetic results, and fewer postoperative complications. This article thoroughly analyzes recent research findings and relevant literature reports, delving into the evolution, primary classifications, indications, contraindications, strengths, and controversies of NOSES in colorectal cancer. The aim is to offer a reference for clinical application.展开更多
目的:探讨在(疾病)诊断相关分类(diagnosis related groups,DRGs)形势下,腹腔镜结直肠癌经自然腔道取标本(NOSES)手术方式改进及其可行性。方法:回顾性分析安阳市肿瘤医院2019年2月至2021年2月实施DRGs的42例改进后的腹腔镜结直肠癌NOSE...目的:探讨在(疾病)诊断相关分类(diagnosis related groups,DRGs)形势下,腹腔镜结直肠癌经自然腔道取标本(NOSES)手术方式改进及其可行性。方法:回顾性分析安阳市肿瘤医院2019年2月至2021年2月实施DRGs的42例改进后的腹腔镜结直肠癌NOSES术,并与同期进行常规腹腔镜结直肠癌手术的238例患者在费用、治疗结果、并发症等方面相比较。结果:NOSES改进组42例患者DRGs控费成功率为95.2%(40/42),与常规腹腔镜组在DRGs费用及近期并发症发生率方面无显著性差异(P>0.05)。结论:腹腔镜结直肠癌NOSES改进手术可以达到DRGs费用标准,手术安全可靠,应用双7号丝线代替部分直线切割闭合器是可行的。展开更多
文摘Nosing process of circular metal tubes in empty and polyurethane foam-filled conditions on a semispherical rigid die was analyzed by theoretical and experimental methods.A new theoretical model of plastic deformation of circular metal tubes was demonstrated during the nosing process on a rigid semispherical die.Based on the analytical model,some theoretical relations were calculated to estimate instantaneous forming load and dissipated energy of empty and foam-filled circular metal tubes versus axial displacement.Some circular brazen and aluminum tubes were prepared and shaped into semispherical nosed nozzles to verify the present theory.Comparison of theoretical predictions and the corresponding experimental measurements reveals that predicted load?displacement and dissipated energy?displacement diagrams by theoretical formulas have a good correlation with the corresponding experimental curves and it proves verity of the theory.Also,the present theory shows that dissipated energy and axial load of empty tubes depend on material type,wall thickness and diameter of the tubes and they are independent of tube initial length.Furthermore,the experimental results show that the presence of polyethylene Teflon-constraints increases ultimate axial displacement of the forming process.
基金Supported by National Institute of Health GrantsNo.P30 CA015083+2 种基金No.U01 CA182940No.U54 CA163004Kathy and Russ Van Cleve Endowment for Gastroenterology Research(all to Wang KK)
文摘Volatile organic compounds(VOCs) emitted from stool are the components of the smell of stool representing the end products of microbial activity and metabolism that can be used to diagnose disease. Despite the abundance of hydrogen, carbon dioxide, and methane that have already been identified in human flatus, the small portion of trace gases making up the VOCs emitted from stool include organic acids, alcohols, esters, heterocyclic compounds, aldehydes, ketones, and alkanes, among others. These are the gases that vary among individuals in sickness and in health, in dietary changes, and in gut microbial activity. Electronic nose devices are analytical and pattern recognition platforms that can utilize mass spectrometry or electrochemical sensors to detect these VOCs in gas samples. When paired with machine-learning and pattern recognition algorithms, this can identify patterns of VOCs, and thus patterns of smell, that can be used to identify disease states. In this review, we provide a clinical background of VOC identification, electronic nose development, and review gastroenterology applications toward diagnosing disease by the volatile headspace analysis of stool.
基金supported by the International Research Collaboration Co-Fund of Qatar University(Grant No.IRCC-2022-569).
文摘Lung diseases pose a significant threat to public health worldwide,resulting in a substantial number of fatalities.Diseases such as chronic obstructive pulmonary disease and lung cancer constitute two of the three deadliest diseases worldwide,contributing to over 3 million deaths annually.This study offered a comparative analysis of different diagnostic techniques used for lung pathologies from an engineering standpoint.The review concentrated on intelligent detection methods,including electronic nose,computer vision(CV),or image processing,and biosensors such as graphene-field effect transistor(FET).The E-nose-based detection technique uses electronic sensors to recognize volatile organic compounds(VOCs)in the exhaled breath.These VOCs can aid in the diagnosis of lung pathologies such as pneumonia.The CV processing method involves the application of advanced imaging techniques and machine learning algorithms to scrutinize and diagnose lung pathologies and ventilatorassociated pneumonia(VAP).Lastly,biosensors employ the exceptional properties of these materials to identify specific biomarkers in biological samples.This information can be used to diagnose lung pathologies and VAP.This study examined the current state-of-the-art methods and offers a comprehensive analysis of their advantages and disadvantages from an engineering perspective.The study underscored the potential of these techniques to enhance the diagnosis of lung pathologies and VAP and presents the advances in the field of smart biomedical applications.Additionally,it emphasized the necessity for further research to optimize their performance and clinical usefulness.
文摘Kong Weili is my classmate and she is my good friend,either①•She is thirteen years old this year.She isn’t very tall,and her eyes,nose and mouth are very small,but I think she looks very beautiful.
文摘I love dogs because they are so friendly and lovely.With bright eyes,dogs can see things in the dark.Their noses are very sensitive,and this helps them find things easily.My pet dog is named Dahu.He is white with long ears.Every day when I come back home from school,he runs to me happily and wags his tail.We often play games together.He likes to chase a ball,and I throw the ball far,then he runs quickly to bring it back.
基金supported by the National Research Project“Variable CAmber wing TechNology(VCAN)”,China。
文摘Climate change has prompted the aviation industry to reduce greenhouse gas emissions.Variable-camber leading edges,with their adaptable aerodynamic shapes,hold significant potential for laminar flow wings and contribute to greener aviation.In response to this need,this paper proposes a design optimization method for a variable-camber leading edge featuring an outer variablethickness composite compliant skin and an inner open-kinematic-chain mechanism.The optimization methodology employs a fiber continuity model based on a ply-drop sequence,a guiding sequence and a thickness sequence to describe the variable-thickness composite compliant skin structure,enabling direct generation of a composite layup sequence that meets fiber continuity criteria.Additionally,the design methodology for the inner open kinematic chain considers the rigidflexible coupling effect and analyzes the number of driving ribs along the span-wise direction.Finally,a full-scale physical prototype for a large-scale civil aircraft is developed and experimented in the FL-10 wind tunnel,demonstrating that the variable-camber leading edge can smoothly and precisely achieve its target shape and hold its final profile under the corresponding aerodynamic loads,thereby validating the proposed design methodology.
基金the National Natural Science Foundation of China(Grant Nos.52422808,52378401)to provide funds for this research。
文摘The non-scaling effect on the penetration depth of rigid projectiles is an important issue that must be considered when extending the results of scaled experiments to prototype scenes.In this study,the evolution of the stress and strain of the target under penetration was analyzed.Expressions for the penetration resistance and penetration depth were obtained based on the conservation equation and continuity condition of the target.The penetration coefficients that characterize the nose shape,target resistance,and non-scaling effect were defined.Simplified calculation methods for the coefficients within the range of rigid projectile penetration were developed.Two methods for estimating the target parameters are proposed.The results show that the non-scaling effect is related to the failure process of the target and depends on the ratio of cavity radius to comminuted region radius.The nose shape coefficient can be approximated as a linear function of the length-to-diameter ratio of the nose.The noseshape coefficient of a flat-nosed projectile is 0.57.The caliber coefficient is related to the projectile diameter and reflects the non-scaling effect,which increases with the projectile diameter.A practical formula for calculating the penetration depth of rigid projectiles considering the non-scaling effect is also proposed.This formula is in good agreement with penetration experiments on rock and concrete.
基金supported by Australia Research Council through the Linkage Project(Grant No.LP200100110).
文摘Swing nose crossings(SNXs)have been widely used in heavy haul railways to create a smoother load transfer and hence reduced impact load.However,the current design of SNXs hasn’t been fully examined under heavy haul operating conditions.Additionally,maintenance guidelines for SNX wear-related issues in Australian heavy haul railways are relatively lacking.As such,this study aims to investigate the dynamic response of the wheel-rail contact and analyse the wear performance of an SNX currently used in Australian heavy haul railways.Dynamic implicit-explicit finite element analysis was conducted to simulate the wheel-rail contact along the SNX.The distribution of the wear intensity over the SNX was identified by using a local contact-based wear model.The influence of various scenarios on wear was also explored.The results verify the improved dynamic performance of the SNX,as the increased contact force after load transfer remains below 1.2 times the static load.The findings also indicate that the decrease in relative height and increase in nose rail inclination result in greater wear on the nose rail.Notably,the SNX considered in the current study exhibits better wear performance when used with moderately worn wheels.
文摘This paper presents a novel method for reconstructing a highly accurate 3D nose model of the human from 2D images and pre-marked landmarks based on algorithmic methods.The study focuses on the reconstruction of a 3D nose model tailored for applications in healthcare and cosmetic surgery.The approach leverages advanced image processing techniques,3D Morphable Models(3DMM),and deformation techniques to overcome the limita-tions of deep learning models,particularly addressing the interpretability issues commonly encountered in medical applications.The proposed method estimates the 3D coordinates of landmark points using a 3D structure estimation algorithm.Sub-landmarks are extracted through image processing techniques and interpolation.The initial surface is generated using a 3DMM,though its accuracy remains limited.To enhance precision,deformation techniques are applied,utilizing the coordinates of 76 identified landmarks and sub-landmarks.The resulting 3D nose model is constructed based on algorithmic methods and pre-marked landmarks.Evaluation of the 3D model is conducted by comparing landmark distances and shape similarity with expert-determined ground truth on 30 Vietnamese volunteers aged 18 to 47,all of whom were either preparing for or required nasal surgery.Experimental results demonstrate a strong agreement between the reconstructed 3D model and the ground truth.The method achieved a mean landmark distance error of 0.631 mm and a shape error of 1.738 mm,demonstrating its potential for medical applications.
文摘经自然腔道取标本手术(Natural Orifice Specimen Extraction Surgery, NOSES)避免了腹壁的辅助切口,有极佳的微创效果。与传统腹腔镜手术相比,NOSES在确保彻底切除肿瘤的同时也最大限度地保留了腹壁原有的功能,规避了与腹壁切口相关的并发症,具有术后恢复快、疼痛轻、美容效果好以及术后并发症少等优点。文章综合分析了近年来有关文献的研究成果与报道,深入探讨了经自然腔道取标本手术(NOSES)在结直肠癌领域的发展历程、主要分类、适应症与禁忌症、优点与争议等方面,旨在为临床应用提供参考。Natural Orifice Specimen Extraction Surgery (NOSES) eliminates the need for auxiliary abdominal wall incisions, offering exceptional minimally invasive outcomes. Compared to traditional laparoscopic surgery, NOSES ensures complete tumor removal while preserving the abdominal wall’s natural function to the greatest extent, thus sidestepping complications linked to abdominal wall incisions. It boasts advantages such as swift postoperative recovery, minimal pain, excellent cosmetic results, and fewer postoperative complications. This article thoroughly analyzes recent research findings and relevant literature reports, delving into the evolution, primary classifications, indications, contraindications, strengths, and controversies of NOSES in colorectal cancer. The aim is to offer a reference for clinical application.
文摘目的:探讨在(疾病)诊断相关分类(diagnosis related groups,DRGs)形势下,腹腔镜结直肠癌经自然腔道取标本(NOSES)手术方式改进及其可行性。方法:回顾性分析安阳市肿瘤医院2019年2月至2021年2月实施DRGs的42例改进后的腹腔镜结直肠癌NOSES术,并与同期进行常规腹腔镜结直肠癌手术的238例患者在费用、治疗结果、并发症等方面相比较。结果:NOSES改进组42例患者DRGs控费成功率为95.2%(40/42),与常规腹腔镜组在DRGs费用及近期并发症发生率方面无显著性差异(P>0.05)。结论:腹腔镜结直肠癌NOSES改进手术可以达到DRGs费用标准,手术安全可靠,应用双7号丝线代替部分直线切割闭合器是可行的。
