The visual noise of each light intensity area is different when the image is drawn by Monte Carlo method.However,the existing denoising algorithms have limited denoising performance under complex lighting conditions a...The visual noise of each light intensity area is different when the image is drawn by Monte Carlo method.However,the existing denoising algorithms have limited denoising performance under complex lighting conditions and are easy to lose detailed information.So we propose a rendered image denoising method with filtering guided by lighting information.First,we design an image segmentation algorithm based on lighting information to segment the image into different illumination areas.Then,we establish the parameter prediction model guided by lighting information for filtering(PGLF)to predict the filtering parameters of different illumination areas.For different illumination areas,we use these filtering parameters to construct area filters,and the filters are guided by the lighting information to perform sub-area filtering.Finally,the filtering results are fused with auxiliary features to output denoised images for improving the overall denoising effect of the image.Under the physically based rendering tool(PBRT)scene and Tungsten dataset,the experimental results show that compared with other guided filtering denoising methods,our method improves the peak signal-to-noise ratio(PSNR)metrics by 4.2164 dB on average and the structural similarity index(SSIM)metrics by 7.8%on average.This shows that our method can better reduce the noise in complex lighting scenesand improvethe imagequality.展开更多
Lu Xun’s short stories play a prominent role in the history of modern Chinese literature,and a number of Sinologists have studied them and published their English translations.This paper selects“YīJiàn Xiǎo S...Lu Xun’s short stories play a prominent role in the history of modern Chinese literature,and a number of Sinologists have studied them and published their English translations.This paper selects“YīJiàn Xiǎo Shì”in Lu Xun’s collection“Call to Arms”as the object of study,taking hypotaxis and parataxis as the starting point,and compares the translation of Yang Hsien-yi and Gladys Yang with the original version,studying the differences between the them in the process of C-E translation.It is hoped that some flexible conversion strategies in English-Chinese translation can be learned from the translation research.展开更多
With technological advancements,virtual reality(VR),once limited to high-end professional applications,is rapidly expanding into entertainment and broader consumer domains.However,the inherent contradiction between mo...With technological advancements,virtual reality(VR),once limited to high-end professional applications,is rapidly expanding into entertainment and broader consumer domains.However,the inherent contradiction between mobile hardware computing power and the demand for high-resolution,high-refresh-rate rendering has intensified,leading to critical bottlenecks,including frame latency and power overload,which constrain large-scale applications of VR systems.This study systematically analyzes four key technologies for efficient VR rendering:(1)foveated rendering,which dynamically reduces rendering precision in peripheral regions based on the physiological characteristics of the human visual system(HVS),thereby significantly decreasing graphics computation load;(2)stereo rendering,optimized through consistent stereo rendering acceleration algorithms;(3)cloud rendering,utilizing object-based decomposition and illumination-based decomposition for distributed resource scheduling;and(4)low-power rendering,integrating parameter-optimized rendering,super-resolution technology,and frame-generation technology to enhance mobile energy efficiency.Through a systematic review of the core principles and optimization approaches of these technologies,this study establishes research benchmarks for developing efficient VR systems that achieve high fidelity and low latency while providing further theoretical support for the engineering implementation and industrial advancement of VR rendering technologies.展开更多
Currently,the main idea of iterative rendering methods is to allocate a fixed number of samples to pixels that have not been fully rendered by calculating the completion rate.It is obvious that this strategy ignores t...Currently,the main idea of iterative rendering methods is to allocate a fixed number of samples to pixels that have not been fully rendered by calculating the completion rate.It is obvious that this strategy ignores the changes in pixel values during the previous rendering process,which may result in additional iterative operations.展开更多
Background Physics-based differentiable rendering(PBDR)aims to propagate gradients from scene parameters to image pixels or vice versa.The physically correct gradients obtained can be used in various applications,incl...Background Physics-based differentiable rendering(PBDR)aims to propagate gradients from scene parameters to image pixels or vice versa.The physically correct gradients obtained can be used in various applications,including inverse rendering and machine learning.Currently,two categories of methods are prevalent in the PBDR community:reparameterization and boundary sampling methods.The state-of-the-art boundary sampling methods rely on a guiding structure to calculate the gradients efficiently.They utilize the rays generated in traditional path-tracing methods and project them onto the object silhouette boundary to initialize the guiding structure.Methods In this study,we propose an augmentation of previous projective-sampling-based boundary-sampling methods in a bidirectional manner.Specifically,we utilize the rays spawned from the sensors and also employ the rays emitted by the emitters to initialize the guiding structure.Results To demonstrate the benefits of our technique,we perform a comparative analysis of differentiable rendering and inverse rendering performance.We utilize a range of synthetic scene examples and evaluate our method against state-of-the-art projective-sampling-based differentiable rendering methods.Conclusions The experiments show that our method achieves lower variance gradients in the forward differentiable rendering process and better geometry reconstruction quality in the inverse-rendering results.展开更多
Haptic teleoperation in nuclear and aerospace applications faces challenges such as a limited workspace,high payload demands,and the need for both coarse positioning and fine manipulation.Existing commercial systems o...Haptic teleoperation in nuclear and aerospace applications faces challenges such as a limited workspace,high payload demands,and the need for both coarse positioning and fine manipulation.Existing commercial systems often lack structural consistency between master and slave devices,which leads to complex motion mapping and limited adaptability.This paper presents a modular isomorphic haptic master device and dual-mode control strategy tailored for these environments.Two reconfigurable versions(5-DOF and 6-DOF)were developed to match the task-specific slave arms.The system supports autonomous-to-manual switching,joint and end-effector mapping,and real-time haptic rendering.Simulations and experiments verified their performance in representative scenarios.The proposed solution addresses structural mismatches and control inflexibility through a scalable task-driven design for high-risk remote operations.展开更多
The rice variety,Co 51,was specifically selected for the development of white polished rice,brown rice(BR),and germinated brown rice(GBR).GBR rendered significant increases in nutrients,including dietary fiber,resista...The rice variety,Co 51,was specifically selected for the development of white polished rice,brown rice(BR),and germinated brown rice(GBR).GBR rendered significant increases in nutrients,including dietary fiber,resistant starch,total antioxidant activity,γ-amino butyric acid(GABA),γ-oryzanol,and ferulic acid content compared with BR.The cooked GBR and white polished rice(120 g)were served with a known quantity of pulses and vegetables without affecting the physical activities of selected groups and the total experimentation period spanned 120 d.At the end of the study period,the experimental group consuming GBR showed a significant decrease in fasting blood glucose(FBG),average glycated hemoglobin(HbA1c),total cholesterol(TC),triglycerides(TG),and low-density lipoprotein cholesterol(LDL-C),compared with the group taking white polished rice.These findings suggest that owing to GBR’s better nutrient composition and bioactive functional ingredients,the long-term consumption of GBR would effectively lower the risk of prediabetes related to FBG,HbA1c,and TG.展开更多
This paper studies polygon simplification algorithms for 3D models,focuses on the optimization algorithm of quadratic error metric(QEM),explores the impacts of different methods on the simplification of different mode...This paper studies polygon simplification algorithms for 3D models,focuses on the optimization algorithm of quadratic error metric(QEM),explores the impacts of different methods on the simplification of different models,and develops a web-based visualization application.Metrics such as the Hausdorff distance are used to evaluate the balance between the degree of simplification and the retention of model details.展开更多
Background In recent years,the demand for interactive photorealistic three-dimensional(3D)environments has increased in various fields,including architecture,engineering,and entertainment.However,achieving a balance b...Background In recent years,the demand for interactive photorealistic three-dimensional(3D)environments has increased in various fields,including architecture,engineering,and entertainment.However,achieving a balance between the quality and efficiency of high-performance 3D applications and virtual reality(VR)remains challenging.Methods This study addresses this issue by revisiting and extending view interpolation for image-based rendering(IBR),which enables the exploration of spacious open environments in 3D and VR.Therefore,we introduce multimorphing,a novel rendering method based on the spatial data structure of 2D image patches,called the image graph.Using this approach,novel views can be rendered with up to six degrees of freedom using only a sparse set of views.The rendering process does not require 3D reconstruction of the geometry or per-pixel depth information,and all relevant data for the output are extracted from the local morphing cells of the image graph.The detection of parallax image regions during preprocessing reduces rendering artifacts by extrapolating image patches from adjacent cells in real-time.In addition,a GPU-based solution was presented to resolve exposure inconsistencies within a dataset,enabling seamless transitions of brightness when moving between areas with varying light intensities.Results Experiments on multiple real-world and synthetic scenes demonstrate that the presented method achieves high"VR-compatible"frame rates,even on mid-range and legacy hardware,respectively.While achieving adequate visual quality even for sparse datasets,it outperforms other IBR and current neural rendering approaches.Conclusions Using the correspondence-based decomposition of input images into morphing cells of 2D image patches,multidimensional image morphing provides high-performance novel view generation,supporting open 3D and VR environments.Nevertheless,the handling of morphing artifacts in the parallax image regions remains a topic for future research.展开更多
High-fidelity tactile rendering offers significant potential for improving the richness and immersion of touchscreen interactions.This study focuses on a quantitative description of tactile rendering fidelity using a ...High-fidelity tactile rendering offers significant potential for improving the richness and immersion of touchscreen interactions.This study focuses on a quantitative description of tactile rendering fidelity using a custom-designed hybrid electrovibration and mechanical vibration(HEM)device.An electrovibration and mechanical vibration(EMV)algorithm that renders 3D gratings with different physical heights was proposed and shown to achieve 81%accuracy in shape recognition.Models of tactile rendering fidelity were established based on the evaluation of the height discrimination threshold,and the psychophysical-physical relationships between the discrimination and reference heights were well described by a modification of Weber’s law,with correlation coefficients higher than 0.9.The physiological-physical relationship between the pulse firing rate and the physical stimulation voltage was modeled using the Izhikevich spiking model with a logarithmic relationship.展开更多
The utilization of phosphors that achieve full-spectrum lighting has emerged as a prevailing trend in the advancement of white light-emitting diode(WLED)lighting.In this study,we successfully prepared a novel green ph...The utilization of phosphors that achieve full-spectrum lighting has emerged as a prevailing trend in the advancement of white light-emitting diode(WLED)lighting.In this study,we successfully prepared a novel green phosphor Ba_(2)Sc_(2)((BO_(3))_(2)B_(2)O_(5)):Ce^(3+)(BSBO:Ce^(3+))that can be utilized for full-spectrum lighting and low-temperature sensors.BSBO:Ce^(3+)exhibits a broad-band excitation spectrum centered at 410 nm,and a broad-band emission spectrum centered at 525 nm.The internal and external quantum efficiencies of BSBO:Ce^(3+)are 99%and 49%,respectively.The thermal stability of BSBO:Ce^(3+)can be improved by substituting partial Sc atoms with smaller cations.The thermal quenching mechanism of BSBO:Ce^(3+)and the lattice occupancy of Ce ions in BSBO are discussed in detail.Furthermore,by combining the green phosphor BSBO:Ce^(3+),the commercial blue phosphor and the red phosphor on a 405 nm chip,a white light source was obtained with a high average color rendering index(CRI)of 96.6,a low correlated color temperature(CCT)of 3988 K,and a high luminous efficacy of 88.0 Im/W.The lu-minous efficacy of the WLED exhibits negligible degradation during the 1000 h light aging experiment.What's more,an emission peak at 468 nm appears when excited at 352 nm and 80 K,however,the relative intensity of the peaks at 468 and 525 nm gradually weakens with increasing temperature,indicating the potential of this material as a low-temperature sensor.展开更多
Aim: To assess the quality of high-resolution CT section planes(HRCT), multi-planar reformation(MPR) and 3-dimensional volume rendered computer tomography(3D-CTVR) were here used in the fine differential diagnosis of ...Aim: To assess the quality of high-resolution CT section planes(HRCT), multi-planar reformation(MPR) and 3-dimensional volume rendered computer tomography(3D-CTVR) were here used in the fine differential diagnosis of ossicular chain in the case of conductive hearing loss with intact tympanic membrane.Methods: Here, 17 cases of otosclerosis and 22 cases of ossicular chain deformity were selected. All patients had normal external ear canals,intact tympanic membranes, conductive hearing loss, type A tympanograms, and negative Gelle's tests. The respective radiological reports of the status of the ossicles via 3 protocols were compared to surgical findings. The quantitative assessments of the representation of different segments of the ossicular chain were based on a 3-point scoring system.Results: MPR and CTVR imaging both showed the integrity of whole ossicular chain well. MPR and CTVR imaging were found to be superior to section planes with respect to showing the superstructure of the stapes and malformations(P > 0.05).Conclusion: CTVR and MPR imaging were found to be better able to show the whole ossicular chain in the conductive hearing loss with normal tympanic membranes. Furthermore, the use of these techniques can have profound contributive value in the differential diagnosis of otosclerosis and ossicular chain absence or malformation.展开更多
In order to resolve the conflict between the limited resources of embedded devices and the growing amount of massive image data to be shown, a solution for fast images rendering in embedded devices is proposed and imp...In order to resolve the conflict between the limited resources of embedded devices and the growing amount of massive image data to be shown, a solution for fast images rendering in embedded devices is proposed and implemented. First, an improved algorithm of a multi-resolution file-pyramid construction which is used for the organization of massive image data is presented. Then, a strategy, adopting technologies such as view-dependent levels of detail, target-tiles quick search and tiles seamless connection, is presented for fast scheduling and viewing of images. The results show that compared with the solution of multi-scale image representations based on wavelet, the proposed solution can improve the rendering speed, and the rendering speed does not depend on the image size, though it increases some data storage space. And the proposed solution is suitable for embedded devices and friendly experience.展开更多
渲染是一种计算机图形图像生成技术,它以存储在计算机中的几何场景模型为基础,经过附加色彩、纹理及材质,并根据设定的光照条件及场景光照关系,计算生成具有高真实度的视景图像。实现3D动画渲染十分消耗计算机的性能,为了减少3D动画渲...渲染是一种计算机图形图像生成技术,它以存储在计算机中的几何场景模型为基础,经过附加色彩、纹理及材质,并根据设定的光照条件及场景光照关系,计算生成具有高真实度的视景图像。实现3D动画渲染十分消耗计算机的性能,为了减少3D动画渲染所花费的时间,利用德国maxon公司Cinema 4D软件的Cinema 4D Team Render对3D动画进行分布式渲染测试。结果表明,此种方法确实可以成倍地减少3D动画渲染所花费的时间。展开更多
基金supported by the National Natural Science(No.U19A2063)the Jilin Provincial Development Program of Science and Technology (No.20230201080GX)the Jilin Province Education Department Scientific Research Project (No.JJKH20230851KJ)。
文摘The visual noise of each light intensity area is different when the image is drawn by Monte Carlo method.However,the existing denoising algorithms have limited denoising performance under complex lighting conditions and are easy to lose detailed information.So we propose a rendered image denoising method with filtering guided by lighting information.First,we design an image segmentation algorithm based on lighting information to segment the image into different illumination areas.Then,we establish the parameter prediction model guided by lighting information for filtering(PGLF)to predict the filtering parameters of different illumination areas.For different illumination areas,we use these filtering parameters to construct area filters,and the filters are guided by the lighting information to perform sub-area filtering.Finally,the filtering results are fused with auxiliary features to output denoised images for improving the overall denoising effect of the image.Under the physically based rendering tool(PBRT)scene and Tungsten dataset,the experimental results show that compared with other guided filtering denoising methods,our method improves the peak signal-to-noise ratio(PSNR)metrics by 4.2164 dB on average and the structural similarity index(SSIM)metrics by 7.8%on average.This shows that our method can better reduce the noise in complex lighting scenesand improvethe imagequality.
基金The paper is part of the achievements of“Research of the English Translation of Lu Xun’s Short Stories and Their Dissemination”(鲁迅小说英译及传播研究),a Shanghai City College Students’project in 2023.Its serial number is SH2023141.
文摘Lu Xun’s short stories play a prominent role in the history of modern Chinese literature,and a number of Sinologists have studied them and published their English translations.This paper selects“YīJiàn Xiǎo Shì”in Lu Xun’s collection“Call to Arms”as the object of study,taking hypotaxis and parataxis as the starting point,and compares the translation of Yang Hsien-yi and Gladys Yang with the original version,studying the differences between the them in the process of C-E translation.It is hoped that some flexible conversion strategies in English-Chinese translation can be learned from the translation research.
基金Supported by the National Key R&D Program of China under grant No.2022YFB3303203the National Natural Science Foundation of China under grant No.62272275.
文摘With technological advancements,virtual reality(VR),once limited to high-end professional applications,is rapidly expanding into entertainment and broader consumer domains.However,the inherent contradiction between mobile hardware computing power and the demand for high-resolution,high-refresh-rate rendering has intensified,leading to critical bottlenecks,including frame latency and power overload,which constrain large-scale applications of VR systems.This study systematically analyzes four key technologies for efficient VR rendering:(1)foveated rendering,which dynamically reduces rendering precision in peripheral regions based on the physiological characteristics of the human visual system(HVS),thereby significantly decreasing graphics computation load;(2)stereo rendering,optimized through consistent stereo rendering acceleration algorithms;(3)cloud rendering,utilizing object-based decomposition and illumination-based decomposition for distributed resource scheduling;and(4)low-power rendering,integrating parameter-optimized rendering,super-resolution technology,and frame-generation technology to enhance mobile energy efficiency.Through a systematic review of the core principles and optimization approaches of these technologies,this study establishes research benchmarks for developing efficient VR systems that achieve high fidelity and low latency while providing further theoretical support for the engineering implementation and industrial advancement of VR rendering technologies.
基金supported partially by the National Natural Science Foundation of China(No.U19A2063)the Jilin Provincial Science&Technology Development Program of China(No.20230201080GX)。
文摘Currently,the main idea of iterative rendering methods is to allocate a fixed number of samples to pixels that have not been fully rendered by calculating the completion rate.It is obvious that this strategy ignores the changes in pixel values during the previous rendering process,which may result in additional iterative operations.
基金Supported by National Natural Science Foundation of China(No.62072020)the Leading Talents in Innovation and Entrepreneurship of Qingdao,China(19-3-2-21-zhc).
文摘Background Physics-based differentiable rendering(PBDR)aims to propagate gradients from scene parameters to image pixels or vice versa.The physically correct gradients obtained can be used in various applications,including inverse rendering and machine learning.Currently,two categories of methods are prevalent in the PBDR community:reparameterization and boundary sampling methods.The state-of-the-art boundary sampling methods rely on a guiding structure to calculate the gradients efficiently.They utilize the rays generated in traditional path-tracing methods and project them onto the object silhouette boundary to initialize the guiding structure.Methods In this study,we propose an augmentation of previous projective-sampling-based boundary-sampling methods in a bidirectional manner.Specifically,we utilize the rays spawned from the sensors and also employ the rays emitted by the emitters to initialize the guiding structure.Results To demonstrate the benefits of our technique,we perform a comparative analysis of differentiable rendering and inverse rendering performance.We utilize a range of synthetic scene examples and evaluate our method against state-of-the-art projective-sampling-based differentiable rendering methods.Conclusions The experiments show that our method achieves lower variance gradients in the forward differentiable rendering process and better geometry reconstruction quality in the inverse-rendering results.
基金Supported by National Key Research and Development Program of China(Grant No.2022YFE0112500).
文摘Haptic teleoperation in nuclear and aerospace applications faces challenges such as a limited workspace,high payload demands,and the need for both coarse positioning and fine manipulation.Existing commercial systems often lack structural consistency between master and slave devices,which leads to complex motion mapping and limited adaptability.This paper presents a modular isomorphic haptic master device and dual-mode control strategy tailored for these environments.Two reconfigurable versions(5-DOF and 6-DOF)were developed to match the task-specific slave arms.The system supports autonomous-to-manual switching,joint and end-effector mapping,and real-time haptic rendering.Simulations and experiments verified their performance in representative scenarios.The proposed solution addresses structural mismatches and control inflexibility through a scalable task-driven design for high-risk remote operations.
基金financially supported by the Indian Council of Agricultural Research-Central Institute of Women in Agriculture, Government of India, and Tamil Nadu Agricultural University, India
文摘The rice variety,Co 51,was specifically selected for the development of white polished rice,brown rice(BR),and germinated brown rice(GBR).GBR rendered significant increases in nutrients,including dietary fiber,resistant starch,total antioxidant activity,γ-amino butyric acid(GABA),γ-oryzanol,and ferulic acid content compared with BR.The cooked GBR and white polished rice(120 g)were served with a known quantity of pulses and vegetables without affecting the physical activities of selected groups and the total experimentation period spanned 120 d.At the end of the study period,the experimental group consuming GBR showed a significant decrease in fasting blood glucose(FBG),average glycated hemoglobin(HbA1c),total cholesterol(TC),triglycerides(TG),and low-density lipoprotein cholesterol(LDL-C),compared with the group taking white polished rice.These findings suggest that owing to GBR’s better nutrient composition and bioactive functional ingredients,the long-term consumption of GBR would effectively lower the risk of prediabetes related to FBG,HbA1c,and TG.
文摘This paper studies polygon simplification algorithms for 3D models,focuses on the optimization algorithm of quadratic error metric(QEM),explores the impacts of different methods on the simplification of different models,and develops a web-based visualization application.Metrics such as the Hausdorff distance are used to evaluate the balance between the degree of simplification and the retention of model details.
基金Supported by the Bavarian Academic Forum(BayWISS),as a part of the joint academic partnership digitalization program.
文摘Background In recent years,the demand for interactive photorealistic three-dimensional(3D)environments has increased in various fields,including architecture,engineering,and entertainment.However,achieving a balance between the quality and efficiency of high-performance 3D applications and virtual reality(VR)remains challenging.Methods This study addresses this issue by revisiting and extending view interpolation for image-based rendering(IBR),which enables the exploration of spacious open environments in 3D and VR.Therefore,we introduce multimorphing,a novel rendering method based on the spatial data structure of 2D image patches,called the image graph.Using this approach,novel views can be rendered with up to six degrees of freedom using only a sparse set of views.The rendering process does not require 3D reconstruction of the geometry or per-pixel depth information,and all relevant data for the output are extracted from the local morphing cells of the image graph.The detection of parallax image regions during preprocessing reduces rendering artifacts by extrapolating image patches from adjacent cells in real-time.In addition,a GPU-based solution was presented to resolve exposure inconsistencies within a dataset,enabling seamless transitions of brightness when moving between areas with varying light intensities.Results Experiments on multiple real-world and synthetic scenes demonstrate that the presented method achieves high"VR-compatible"frame rates,even on mid-range and legacy hardware,respectively.While achieving adequate visual quality even for sparse datasets,it outperforms other IBR and current neural rendering approaches.Conclusions Using the correspondence-based decomposition of input images into morphing cells of 2D image patches,multidimensional image morphing provides high-performance novel view generation,supporting open 3D and VR environments.Nevertheless,the handling of morphing artifacts in the parallax image regions remains a topic for future research.
基金Supported by the National Natural Science Foundation of China under Grants 61631010 and 61806085.
文摘High-fidelity tactile rendering offers significant potential for improving the richness and immersion of touchscreen interactions.This study focuses on a quantitative description of tactile rendering fidelity using a custom-designed hybrid electrovibration and mechanical vibration(HEM)device.An electrovibration and mechanical vibration(EMV)algorithm that renders 3D gratings with different physical heights was proposed and shown to achieve 81%accuracy in shape recognition.Models of tactile rendering fidelity were established based on the evaluation of the height discrimination threshold,and the psychophysical-physical relationships between the discrimination and reference heights were well described by a modification of Weber’s law,with correlation coefficients higher than 0.9.The physiological-physical relationship between the pulse firing rate and the physical stimulation voltage was modeled using the Izhikevich spiking model with a logarithmic relationship.
基金the National Natural Science Foundation of China(22003035,21963006,22073061)the Project of Shaanxi Province Youth Science and Technology New Star(2023KJXX-076)the National Training Program of Innovation and Entrepreneurship for Undergraduates(202314390018)。
文摘The utilization of phosphors that achieve full-spectrum lighting has emerged as a prevailing trend in the advancement of white light-emitting diode(WLED)lighting.In this study,we successfully prepared a novel green phosphor Ba_(2)Sc_(2)((BO_(3))_(2)B_(2)O_(5)):Ce^(3+)(BSBO:Ce^(3+))that can be utilized for full-spectrum lighting and low-temperature sensors.BSBO:Ce^(3+)exhibits a broad-band excitation spectrum centered at 410 nm,and a broad-band emission spectrum centered at 525 nm.The internal and external quantum efficiencies of BSBO:Ce^(3+)are 99%and 49%,respectively.The thermal stability of BSBO:Ce^(3+)can be improved by substituting partial Sc atoms with smaller cations.The thermal quenching mechanism of BSBO:Ce^(3+)and the lattice occupancy of Ce ions in BSBO are discussed in detail.Furthermore,by combining the green phosphor BSBO:Ce^(3+),the commercial blue phosphor and the red phosphor on a 405 nm chip,a white light source was obtained with a high average color rendering index(CRI)of 96.6,a low correlated color temperature(CCT)of 3988 K,and a high luminous efficacy of 88.0 Im/W.The lu-minous efficacy of the WLED exhibits negligible degradation during the 1000 h light aging experiment.What's more,an emission peak at 468 nm appears when excited at 352 nm and 80 K,however,the relative intensity of the peaks at 468 and 525 nm gradually weakens with increasing temperature,indicating the potential of this material as a low-temperature sensor.
文摘Aim: To assess the quality of high-resolution CT section planes(HRCT), multi-planar reformation(MPR) and 3-dimensional volume rendered computer tomography(3D-CTVR) were here used in the fine differential diagnosis of ossicular chain in the case of conductive hearing loss with intact tympanic membrane.Methods: Here, 17 cases of otosclerosis and 22 cases of ossicular chain deformity were selected. All patients had normal external ear canals,intact tympanic membranes, conductive hearing loss, type A tympanograms, and negative Gelle's tests. The respective radiological reports of the status of the ossicles via 3 protocols were compared to surgical findings. The quantitative assessments of the representation of different segments of the ossicular chain were based on a 3-point scoring system.Results: MPR and CTVR imaging both showed the integrity of whole ossicular chain well. MPR and CTVR imaging were found to be superior to section planes with respect to showing the superstructure of the stapes and malformations(P > 0.05).Conclusion: CTVR and MPR imaging were found to be better able to show the whole ossicular chain in the conductive hearing loss with normal tympanic membranes. Furthermore, the use of these techniques can have profound contributive value in the differential diagnosis of otosclerosis and ossicular chain absence or malformation.
基金The National Public Benefit Research Foundation of China (No. 201111013-02)
文摘In order to resolve the conflict between the limited resources of embedded devices and the growing amount of massive image data to be shown, a solution for fast images rendering in embedded devices is proposed and implemented. First, an improved algorithm of a multi-resolution file-pyramid construction which is used for the organization of massive image data is presented. Then, a strategy, adopting technologies such as view-dependent levels of detail, target-tiles quick search and tiles seamless connection, is presented for fast scheduling and viewing of images. The results show that compared with the solution of multi-scale image representations based on wavelet, the proposed solution can improve the rendering speed, and the rendering speed does not depend on the image size, though it increases some data storage space. And the proposed solution is suitable for embedded devices and friendly experience.
文摘渲染是一种计算机图形图像生成技术,它以存储在计算机中的几何场景模型为基础,经过附加色彩、纹理及材质,并根据设定的光照条件及场景光照关系,计算生成具有高真实度的视景图像。实现3D动画渲染十分消耗计算机的性能,为了减少3D动画渲染所花费的时间,利用德国maxon公司Cinema 4D软件的Cinema 4D Team Render对3D动画进行分布式渲染测试。结果表明,此种方法确实可以成倍地减少3D动画渲染所花费的时间。
