This study addresses the challenge of directly determining the elastic modulus of complex shaped ceramic products—such as gas turbine combustor tiles—using conventional standardized methods,which are limited by spec...This study addresses the challenge of directly determining the elastic modulus of complex shaped ceramic products—such as gas turbine combustor tiles—using conventional standardized methods,which are limited by specimen geometry.A rapid,non-destructive testing method based on the impulse excitation technique(IET)and a shape factor coefficient was proposed.Three types of shaped ceramic tiles were selected.The elastic modulus of standard rectangular specimens obtained by destructive sampling was used as the reference value,and the shape factor coefficient for each tile type was calibrated by combining the mass and fundamental frequency of the whole tile.Using this coefficient,the elastic modulus of whole tiles was calculated solely from non-destructively measured mass and frequency.The results show that the deviation between the elastic modulus derived from the proposed method and that from destructive testing is less than 5%,confirming the accuracy and reliability of the approach.The method overcomes the shape restrictions inherent in traditional testing,offering a fast,non-destructive solution suitable for onsite quality assessment and process control during the production of shaped ceramic components.展开更多
AIM: To report the surgical technique and efficacy of the tiled transplantation internal limiting membrane(ILM) pedicle flap technique after vitrectomy for 33 patients with large macular hole(MH). METHODS: This study...AIM: To report the surgical technique and efficacy of the tiled transplantation internal limiting membrane(ILM) pedicle flap technique after vitrectomy for 33 patients with large macular hole(MH). METHODS: This study was a prospective noncontrolled interventional study. All patients were treated by vitrectomy, the tiled transplantation ILM pedicle flap and gas tamponade. All patients underwent visual acuity measurements and optical coherence tomography(OCT), during preoperative and the follow-up visits postoperative. RESULTS: Two high-myopic patient had flap dislocation during surgery. The thorough closure of MH following the tiled transplantation ILM pedicle flap technique was ultimately achieved in 31 patients observed by OCT imaging(93.94%) 1 wk after surgery. Visual acuity improved from 1.51±0.31(logMAR) preoperative to 0.92±0.30 6 mo after surgery(P=0.000). There were no significant changes in OCT finding during the follow-up period from 1 mo to 6 mo after surgery. CONCLUSION: The tiled transplantation ILM pedicle flap technique provides bridge for retinal gliosis to achieve successful closures of the large MHs, and the microenvironment of this technique is more similar to the normal physiological conditions.展开更多
SimWall is a user-friendly, stereo tiled display wall system composed of 18 commodity projectors operated by a Linux graphics cluster. Collaborating together, these projectors work as a single logical display capable ...SimWall is a user-friendly, stereo tiled display wall system composed of 18 commodity projectors operated by a Linux graphics cluster. Collaborating together, these projectors work as a single logical display capable of giving a high-resolution show, large-scale, and passive stereo scene. In order to avoid tedious system setup and maintenance, software-based automatic geometry and photometric calibration are used. The software calibration is integrated to the system seamlessly by an on-card transform method and is transparent to users. To end-users, SimWall works just as a common PC, but provides super computing, rendering and displaying ability. In addition, SimWall has stereoscopic function that gives users a semi-immersive experience in polarized passive way. This paper presents system architecture, implementation, and other technical issues such as hardware constraints, projectors alignment, geometry and photometric calibration, implementation of passive stereo, and development of overall soft- ware environment.展开更多
In this paper, a scalable hardware and software architecture for tiled display systems (a.k.a. videowalls), which can be implemented by using low-cost devices, together with a dynamic web-based management and configur...In this paper, a scalable hardware and software architecture for tiled display systems (a.k.a. videowalls), which can be implemented by using low-cost devices, together with a dynamic web-based management and configuration service are proposed. It has been designed to support both stored and live broadcast/broadband content, in mosaic or warp distributions. The displays and devices can be dynamically configured via web in different ways: the displays can create a single display of a larger size;or they can be configured in a customized way in order to playout different media contents in different display combinations. As display renderers, low-cost devices are proposed as the main hardware element to obtain affordable videowall systems. As a proof of concept, two prototypes have been implemented, including an accurate synchronization mechanism based on a Master/Slave control scheme and aggressive and smooth playout adjustment techniques. To evidence the good performance of the prototypes and configuration service, both objective and subjective evaluations have been conducted regarding synchronization accuracy and usability. On the one hand, the mean values of the asynchronies between the video playout processes in each display are kept below 25ms (i.e., frame accuracy). On the other hand, the obtained usability score in the System Usability Scale (SUS) test has been 88.65, which is considered as excellent.展开更多
We demonstrate coherent beam combining of two tiled-aperture single-frequency fibre amplifiers with a total output power of 29.65 W by using the multi-dithering technique. The two laser beams are packaged closely by u...We demonstrate coherent beam combining of two tiled-aperture single-frequency fibre amplifiers with a total output power of 29.65 W by using the multi-dithering technique. The two laser beams are packaged closely by using free-space mirrors side by side into a tiled-aperture with a near-field fill factor of 62%. Active phase control of the amplifier is performed on commercially available digital lock-in amplifiers. Experimental results show that the power contained in the main-lobe in closed-loop is 1.72 times greater than that in open-loop, which is 86% for the ideal case. The fringe contrast of the far-field fringe pattern is as high as 80% when the system is in closed-loop. The beam quality of the combined beam is computed to he BQ = 1.48. The whole system in closed-loop performs well in a long-time observation.展开更多
In the highest-power chirped-pulse amplification lasers, the pulse must be stretched in time, amplified, compressed in a grating compressor and subsequently focused by off-axis parabola to obtain a high peak power. In...In the highest-power chirped-pulse amplification lasers, the pulse must be stretched in time, amplified, compressed in a grating compressor and subsequently focused by off-axis parabola to obtain a high peak power. In the optical terminal, the temporal and spatial effects of mismatched multigrating tiled compressor on the far-field pulse are critical factors to be analysed. In this paper, a k-space raytracing model is proposed for the temporal and spatial analyses of possible errors in a four-grating single-pass tiled compressor. The results show that the last grating affects mainly the partial focal spot, while the middle two gratings affect the temporal waveform, and the partial focal spot needs much higher error control than that in the temporal domain in a picosecond pulse compression.展开更多
After reaching a world record of 10 PW,the peak power development of the titanium-sapphire(Ti:sapphire)PW ultraintense lasers has hit a bottleneck,and it seems to be difficult to continue increasing due to the difficu...After reaching a world record of 10 PW,the peak power development of the titanium-sapphire(Ti:sapphire)PW ultraintense lasers has hit a bottleneck,and it seems to be difficult to continue increasing due to the difficulty of manufacturing larger Ti:sapphire crystals and the limitation of parasitic lasing that can consume stored pump energy.Unlike coherent beam combining,coherent Ti:sapphire tiling is a viable solution for expanding Ti:sapphire crystal sizes,truncating transverse amplified spontaneous emission,suppressing parasitic lasing,and,importantly,not requiring complex space-time tiling control.A theoretical analysis of the above features and an experimental demonstration of high-quality laser amplification are reported.The results show that the addition of a 2×2 tiled Ti:sapphire amplifier to today’s 10 PW ultraintense laser is a viable technique to break the 10 PW limit and directly increase the highest peak power recorded by a factor of 4,further approaching the exawatt class.展开更多
针对瓷砖色差检测中传统方法依赖主观目测导致的结果不稳定问题,提出一种融合纹理与颜色特征的瓷砖色差量化与分级方法。构建包含纹理与颜色双标签的大规模瓷砖数据集TILE-TCR(TILE Texture and Color Recognition),以提升模型对纹理与...针对瓷砖色差检测中传统方法依赖主观目测导致的结果不稳定问题,提出一种融合纹理与颜色特征的瓷砖色差量化与分级方法。构建包含纹理与颜色双标签的大规模瓷砖数据集TILE-TCR(TILE Texture and Color Recognition),以提升模型对纹理与颜色特征的表征能力;同时,构建色差分级数据集TILE-CAG(TILE Chromatic Aberration Grade),用于支持色差分类任务。在此基础上,改进分形编码网络(FENet)的网络结构,即引入空间金字塔池化(SPP)与SE(Squeeze-and-Excitation)模块,从而实现多任务特征提取与关键区域聚焦。然后,通过聚类算法自适应确定色差分级阈值,从而实现色差分级的客观量化。实验结果表明,所提改进方法在瓷砖纹理分类任务中的准确率达到92.82%,较FENet提升了1.84个百分点;在色差分级任务中所提方法的准确率、精确率、召回率和F1分数均超过90%。此外,还搭建了模拟生产流水线,以完成模型的工业部署与实时性测试。而所提方法在常见规格瓷砖上的平均检测时间低于3 s,满足工业传送带在线检测的实时性要求。展开更多
目的：回顾性分析 Tile C 型骨盆骨折患者死亡相关的危险因素。方法2010年1月至2014年12月我院收治的 Tile C 型骨盆骨折患者139例,收集资料包括术前一般情况、伤后就诊时间、休克指数、各类创伤评分、最低氧合指数、伤后6 h 乳酸清除率...目的：回顾性分析 Tile C 型骨盆骨折患者死亡相关的危险因素。方法2010年1月至2014年12月我院收治的 Tile C 型骨盆骨折患者139例,收集资料包括术前一般情况、伤后就诊时间、休克指数、各类创伤评分、最低氧合指数、伤后6 h 乳酸清除率等,采用多因素 Logistic 回归分析死亡相关危险因素。结果入院后死亡41例（29.5%）,其中入院后48 h 内死亡36例（25.9%）。多因素回归分析显示,休克指数＆gt;2（OR=2.591,95%CI 1.041~4.216）、损伤严重程度评分（ISS）≥25分（OR=47.96,95%CI 15.89~147.23）、改良创伤评分（RTS）≤8分（OR=6.917,95%CI 1.147-13.862）、格拉斯哥昏迷评分（GCS）〈9分（OR=4.172,95%CI 2.962~6.268）、最低氧合指数〈200（OR=117.016,95%CI 51.011~176.032）、伤后6 h 乳酸清除率〈10%（OR=2.785,95%CI 1.191~4.892）,以及合并头部损伤（OR=6.302,95%CI 2.270~13.175）或胸部损伤（OR=12.233,95%CI 5.193~33.985）是骨盆骨折患者死亡相关危险因素（P 〈0.01）。早期行血管栓塞治疗有助于降低死亡风险（OR=0.887,95%CI 0.875~0.899）。结论创伤评分高,出现严重休克、昏迷、氧合指数下降和6 h 乳酸清除率降低,合并头部和胸部损伤是导致 Tile C 型骨盆骨折患者死亡的危险因素。展开更多
基金National Key Research and Development Program of China(2023YFB3711200)Key Research and Development Project of Henan Province(231111230700).
文摘This study addresses the challenge of directly determining the elastic modulus of complex shaped ceramic products—such as gas turbine combustor tiles—using conventional standardized methods,which are limited by specimen geometry.A rapid,non-destructive testing method based on the impulse excitation technique(IET)and a shape factor coefficient was proposed.Three types of shaped ceramic tiles were selected.The elastic modulus of standard rectangular specimens obtained by destructive sampling was used as the reference value,and the shape factor coefficient for each tile type was calibrated by combining the mass and fundamental frequency of the whole tile.Using this coefficient,the elastic modulus of whole tiles was calculated solely from non-destructively measured mass and frequency.The results show that the deviation between the elastic modulus derived from the proposed method and that from destructive testing is less than 5%,confirming the accuracy and reliability of the approach.The method overcomes the shape restrictions inherent in traditional testing,offering a fast,non-destructive solution suitable for onsite quality assessment and process control during the production of shaped ceramic components.
基金Supported by the Shaanxi Provincial Social Development Scientific and Technological Project(No.2016SF-133)
文摘AIM: To report the surgical technique and efficacy of the tiled transplantation internal limiting membrane(ILM) pedicle flap technique after vitrectomy for 33 patients with large macular hole(MH). METHODS: This study was a prospective noncontrolled interventional study. All patients were treated by vitrectomy, the tiled transplantation ILM pedicle flap and gas tamponade. All patients underwent visual acuity measurements and optical coherence tomography(OCT), during preoperative and the follow-up visits postoperative. RESULTS: Two high-myopic patient had flap dislocation during surgery. The thorough closure of MH following the tiled transplantation ILM pedicle flap technique was ultimately achieved in 31 patients observed by OCT imaging(93.94%) 1 wk after surgery. Visual acuity improved from 1.51±0.31(logMAR) preoperative to 0.92±0.30 6 mo after surgery(P=0.000). There were no significant changes in OCT finding during the follow-up period from 1 mo to 6 mo after surgery. CONCLUSION: The tiled transplantation ILM pedicle flap technique provides bridge for retinal gliosis to achieve successful closures of the large MHs, and the microenvironment of this technique is more similar to the normal physiological conditions.
基金Project supported by the National Natural Science Foundation of China for Distinguished Young Scholars (No. 60225009)the Major Research Plan of China (No. 90405003)
文摘SimWall is a user-friendly, stereo tiled display wall system composed of 18 commodity projectors operated by a Linux graphics cluster. Collaborating together, these projectors work as a single logical display capable of giving a high-resolution show, large-scale, and passive stereo scene. In order to avoid tedious system setup and maintenance, software-based automatic geometry and photometric calibration are used. The software calibration is integrated to the system seamlessly by an on-card transform method and is transparent to users. To end-users, SimWall works just as a common PC, but provides super computing, rendering and displaying ability. In addition, SimWall has stereoscopic function that gives users a semi-immersive experience in polarized passive way. This paper presents system architecture, implementation, and other technical issues such as hardware constraints, projectors alignment, geometry and photometric calibration, implementation of passive stereo, and development of overall soft- ware environment.
基金partially funded by "Vicerrectorado de Investigación de la Universitat Politècnica de València" under projects with references PAID-1121 and PAID-12-21
文摘In this paper, a scalable hardware and software architecture for tiled display systems (a.k.a. videowalls), which can be implemented by using low-cost devices, together with a dynamic web-based management and configuration service are proposed. It has been designed to support both stored and live broadcast/broadband content, in mosaic or warp distributions. The displays and devices can be dynamically configured via web in different ways: the displays can create a single display of a larger size;or they can be configured in a customized way in order to playout different media contents in different display combinations. As display renderers, low-cost devices are proposed as the main hardware element to obtain affordable videowall systems. As a proof of concept, two prototypes have been implemented, including an accurate synchronization mechanism based on a Master/Slave control scheme and aggressive and smooth playout adjustment techniques. To evidence the good performance of the prototypes and configuration service, both objective and subjective evaluations have been conducted regarding synchronization accuracy and usability. On the one hand, the mean values of the asynchronies between the video playout processes in each display are kept below 25ms (i.e., frame accuracy). On the other hand, the obtained usability score in the System Usability Scale (SUS) test has been 88.65, which is considered as excellent.
文摘We demonstrate coherent beam combining of two tiled-aperture single-frequency fibre amplifiers with a total output power of 29.65 W by using the multi-dithering technique. The two laser beams are packaged closely by using free-space mirrors side by side into a tiled-aperture with a near-field fill factor of 62%. Active phase control of the amplifier is performed on commercially available digital lock-in amplifiers. Experimental results show that the power contained in the main-lobe in closed-loop is 1.72 times greater than that in open-loop, which is 86% for the ideal case. The fringe contrast of the far-field fringe pattern is as high as 80% when the system is in closed-loop. The beam quality of the combined beam is computed to he BQ = 1.48. The whole system in closed-loop performs well in a long-time observation.
基金Project supported by the National High Technology Research and Development Program of China(Grant No.2009AA8044005)
文摘In the highest-power chirped-pulse amplification lasers, the pulse must be stretched in time, amplified, compressed in a grating compressor and subsequently focused by off-axis parabola to obtain a high peak power. In the optical terminal, the temporal and spatial effects of mismatched multigrating tiled compressor on the far-field pulse are critical factors to be analysed. In this paper, a k-space raytracing model is proposed for the temporal and spatial analyses of possible errors in a four-grating single-pass tiled compressor. The results show that the last grating affects mainly the partial focal spot, while the middle two gratings affect the temporal waveform, and the partial focal spot needs much higher error control than that in the temporal domain in a picosecond pulse compression.
基金supported by the National Key R&D Program of China(Grant No.2022YFA1604401)the Shanghai Science and Technology Committee Program(Grant Nos.22560780100 and 23560750200)the National Natural Science Foundation of China(Grant No.61925507).
文摘After reaching a world record of 10 PW,the peak power development of the titanium-sapphire(Ti:sapphire)PW ultraintense lasers has hit a bottleneck,and it seems to be difficult to continue increasing due to the difficulty of manufacturing larger Ti:sapphire crystals and the limitation of parasitic lasing that can consume stored pump energy.Unlike coherent beam combining,coherent Ti:sapphire tiling is a viable solution for expanding Ti:sapphire crystal sizes,truncating transverse amplified spontaneous emission,suppressing parasitic lasing,and,importantly,not requiring complex space-time tiling control.A theoretical analysis of the above features and an experimental demonstration of high-quality laser amplification are reported.The results show that the addition of a 2×2 tiled Ti:sapphire amplifier to today’s 10 PW ultraintense laser is a viable technique to break the 10 PW limit and directly increase the highest peak power recorded by a factor of 4,further approaching the exawatt class.
文摘针对瓷砖色差检测中传统方法依赖主观目测导致的结果不稳定问题,提出一种融合纹理与颜色特征的瓷砖色差量化与分级方法。构建包含纹理与颜色双标签的大规模瓷砖数据集TILE-TCR(TILE Texture and Color Recognition),以提升模型对纹理与颜色特征的表征能力;同时,构建色差分级数据集TILE-CAG(TILE Chromatic Aberration Grade),用于支持色差分类任务。在此基础上,改进分形编码网络(FENet)的网络结构,即引入空间金字塔池化(SPP)与SE(Squeeze-and-Excitation)模块,从而实现多任务特征提取与关键区域聚焦。然后,通过聚类算法自适应确定色差分级阈值,从而实现色差分级的客观量化。实验结果表明,所提改进方法在瓷砖纹理分类任务中的准确率达到92.82%,较FENet提升了1.84个百分点;在色差分级任务中所提方法的准确率、精确率、召回率和F1分数均超过90%。此外,还搭建了模拟生产流水线,以完成模型的工业部署与实时性测试。而所提方法在常见规格瓷砖上的平均检测时间低于3 s,满足工业传送带在线检测的实时性要求。
文摘目的：回顾性分析 Tile C 型骨盆骨折患者死亡相关的危险因素。方法2010年1月至2014年12月我院收治的 Tile C 型骨盆骨折患者139例,收集资料包括术前一般情况、伤后就诊时间、休克指数、各类创伤评分、最低氧合指数、伤后6 h 乳酸清除率等,采用多因素 Logistic 回归分析死亡相关危险因素。结果入院后死亡41例（29.5%）,其中入院后48 h 内死亡36例（25.9%）。多因素回归分析显示,休克指数＆gt;2（OR=2.591,95%CI 1.041~4.216）、损伤严重程度评分（ISS）≥25分（OR=47.96,95%CI 15.89~147.23）、改良创伤评分（RTS）≤8分（OR=6.917,95%CI 1.147-13.862）、格拉斯哥昏迷评分（GCS）〈9分（OR=4.172,95%CI 2.962~6.268）、最低氧合指数〈200（OR=117.016,95%CI 51.011~176.032）、伤后6 h 乳酸清除率〈10%（OR=2.785,95%CI 1.191~4.892）,以及合并头部损伤（OR=6.302,95%CI 2.270~13.175）或胸部损伤（OR=12.233,95%CI 5.193~33.985）是骨盆骨折患者死亡相关危险因素（P 〈0.01）。早期行血管栓塞治疗有助于降低死亡风险（OR=0.887,95%CI 0.875~0.899）。结论创伤评分高,出现严重休克、昏迷、氧合指数下降和6 h 乳酸清除率降低,合并头部和胸部损伤是导致 Tile C 型骨盆骨折患者死亡的危险因素。
