可编辑三维场景的动态3D Tiles构建方法

可编辑的大型三维WebGIS具有一定的应用场景需求,常见的3DTiles数据格式局限于静态场景渲染,在编辑的三维场景中,需要构建动态的3D Tile文件格式和多细节层次(level of detail,Lo D)渲染方法。本文从动态空间索引和多细节层次技术两方面研究Web在线编辑大型三维场景的构建方法,将动态松散八叉树和半边折叠LoD构建算法应用于3D Tiles构建流程中,实现支持可编辑场景的3D Tiles构建与更新。结果表明:(1)松散八叉树索引在计算量上能够实现动态更新的目标,且在视锥体剔除上有着良好的精度;(2)基于半边折叠法进行准实时LoD的构建,能够满足动态场景下实时计算LoD的需求;(3)所构建的3D Tiles场景,配合Three.js等成熟框架并应用WebWorker等技术,能够顺利完成3DTiles的高效调度和渲染。研究成果对城市三维模型在线编辑、动态地理三维场景的加载渲染等相关研究和应用具有一定的参考价值。

Improved Flexible Triboelectric Nanogenerator Based on Tile-Nanostructure for Wireless Human Health Monitor

Triboelectric nanogenerators(TENGs)have emerged as promising candidates for integrating with flexible electronics as self-powered systems owing to their intrinsic flexibility,biocompatibility,and miniaturization.In this study,an improved flexible TENG with a tile-nanostructured MXene/polymethyl methacrylate(PMMA)composite electrode(MP-TENG)is proposed for use in wireless human health monitor.The multifunctional tile-nanostructured MXene/PMMA film,which is self-assembled through vacuum filtration,exhibits good conductivity,excellent charge capacity,and high flexibility.Thus,the MXene/PMMA composite electrode can simultaneously function as a charge-generating,charge-trapping,and charge-collecting layer.Furthermore,the charge-trapping capacity of a tile nanostructure can be optimized on the basis of the PMMA concentration.At a mass fraction of 4%PMMA,the MP-TENG achieves the optimal output performance,with an output voltage of 37.8 V,an output current of 1.8μA,and transferred charge of 14.1 nC.The output power is enhanced over twofold compared with the pure MXene-based TENG.Moreover,the MP-TENG has sufficient power capacity and durability to power small electronic devices.Finally,a wireless human motion monitor based on the MP-TENG is utilized to detect physiological signals in various kinematic motions.Consequently,the proposed performance-enhanced MP-TENG proves a considerable potential for use in health monitoring,telemedicine,and self-powered systems.

基于3D Tiles的大规模三维地质模型共享技术研究

针对三维地质模型的网络共享与发布研究较少,基于3D Tiles提出了一种大规模三维地质模型共享发布方案:首先采用基于二次误差测度(QEM)的半边折叠算法,对模型进行简化,建立分层LOD模型;再利用平面四叉树+纵向固定距离切分的方法对各级模型进行分块,建立瓦片分层结构树;最后计算出所需的几何误差、变换矩阵等参数,并生成3D Tiles瓦片内容及瓦片集描述文件。基于此方案选取了某区域约1000 km^(2)的三维地质体模型进行了实验,实验表明该方案在保障模型的几何特征和细节表现的同时,可对大规模三维地质模型进行高效、流畅的加载与显示。

经皮骶髂置钉内固定联合前环外固定架手术治疗Tile B、C型骨盆骨折患者的疗效观察

目的观察经皮骶髂置钉内固定联合前环外固定架手术治疗Tile B、C型骨盆骨折患者疗效及并发症。方法以2020年1月至2022年12月山东省聊城市中医医院收治的Tile B、C型骨盆骨折患者为研究对象,选择其中接受前路切开复位骨板内固定传统手术的87例患者为传统组,另选择接受经皮骶髂置钉内固定联合前环外固定架手术的89例患者为联合组。比较两组患者手术相关指标,术后3 d、7 d、14 d疼痛视觉模拟评分法(VAS)评分,术后3个月与6个月Majeed功能评分、Matta评分及并发症发生率。结果联合组患者手术时间短于传统组,出血量少于传统组,差异均有统计学意义(P<0.05);两组住院时间、负重行走时间、骨折愈合时间比较,差异均无统计学意义(P>0.05)。两组患者术后3 d、7 d、14 d时VAS评分差异均无统计学意义(P>0.05)。联合组患者术后3个月Majeed功能评分、Matta评分优良率高于传统组,差异具有统计学意义(P<0.05)。两组患者术后6个月Majeed功能评分、优良率差异无统计学意义(P>0.05)。联合组患者并发症发生率低于传统组,差异具有统计学意义(P<0.05)。结论与传统手术治疗Tile B、C型骨盆骨折相比,经皮骶髂置钉内固定联合前环外固定架手术可缩短手术时间,减少术中出血量,降低术后并发症风险。

基于Vector 3D Tiles格式的三维矢量数据可视化研究

为了探究Vector 3D Tiles格式在三维矢量地物表达方面的效果和性能,研究了一套Vector 3D Tiles格式生产和表达工具,用于在Cesium平台上对矢量数据进行可视化展示。主要工作包括两部分:一是将数据从传统的矢量格式转换为Vector 3D Tiles格式,二是在Cesium平台上展示转换后的Vector 3D Tiles数据。为了验证方法可行性,采用广州市地下管线数据开展了实验,对Shapefile、GeoJSON二维矢量格式进行处理,生成Vector 3D Tiles格式后,在Cesium平台上进行三维可视化展示。通过不同格式数据的加载效率和呈现效果比较,证明了矢量切片数据比原始矢量格式加载更快、渲染更平滑。在此基础上,对矢量切片数据基于自定义三维样式的渲染能力进行了验证。

AndEngine引擎结合Tiled编辑器实现游戏中的瓦片地图

在游戏开发过程中,大部分设计者都需要足够大且可以扩展的游戏地图,例如即时战略游戏,使得玩家可以在地图中滚动游戏画面。这类游戏通常会有丰富的背景元素,如果直接使用背景图切换的方式,需要为每个不同的场景准备一张背景图,而且每个背景图都不小,这样会造成资源浪费。相对于创建一张巨大的位图来说,瓦片可以被多次使用,拼接成大图,从而可以在游戏运行时根据需要即刻生成大小不限的地图。瓦片地图既节省了内存,又节省了时间。AndEngine是一款基于Open GL ES技术的Android游戏引擎,为开发者提供了免费且易用的游戏框架,Tiled Map Editor是瓦片地图编辑器。该文着重介绍AndEngine如何解析Tiled编辑器创建的地图文件。

3D打印技术下空心螺钉微创固定对Tile B型骨盆骨折的近期疗效及并发症的影响

目的 探究3D打印技术下空心螺钉微创固定对Tile B型骨盆骨折的近期疗效及并发症的影响。方法 选取四川省广元市中心医院2019年6月至2022年10月收治的80例Tile B型骨盆骨折患者作为研究对象,按照Excel软件随机分组方法分为对照组(40例)与观察组(40例),对照组采用空心螺钉微创固定治疗方法,观察组采用3D打印技术下空心螺钉微创固定治疗方法。比较两组患者治疗指标(手术时间、术中透视次数、伤口愈合时间、功能恢复时间)、治疗效果、并发症发生率及治疗满意度。结果 观察组患者手术时间、伤口愈合时间、功能恢复时间均短于对照组,术中透视次数少于对照组(均P<0.001);观察组治疗有效率高于对照组(90.0%vs. 67.5%,P=0.014);观察组并发症发生率较对照组低(7.5%vs. 27.5%,P=0.019);观察组治疗满意度高于对照组(95.0%vs. 75.0%,P=0.012)。结论 3D打印技术下空心螺钉微创固定治疗Tile B型骨盆骨折可取得良好的治疗效果,能缩短手术时间,促进患者伤口愈合,加快骨盆功能恢复,减少术中透视次数,并能降低患者并发症发生率,使患者获得较高的治疗满意度。

INFIX技术与外固定支架分别联合骶髂关节螺钉治疗Tile B型骨折的效果观察

目的:探讨前环皮下内置外固定架(INFIX)技术与外固定支架分别联合骶髂关节螺钉治疗Tile B型骨折的效果。方法:回顾性分析2019年3月至2022年3月就诊于本院骨科的88例Tile B型骨折患者,其中47例给予INFIX技术+骶髂关节螺钉治疗(INFIX组),41例给予外固定支架+骶髂关节螺钉治疗(外固定支架组),比较两组手术时间、术中出血量、住院时间、术后负重时间、愈合时间、并发症发生率、Matta评分、Majeed评分以及术后1、3、6个月EQ-5D评分及VAS评分。结果:INFIX组住院时间及愈合时间均短于外固定支架组,并发症发生率低于外固定支架组(P<0.05);术后6个月,INFIX组Matta评分优良率(95.74%)高于外固定支架组(80.49%)(P<0.05);INFIX组性生活评分高于外固定支架组(P<0.05);EQ-5D评分及VAS评分组间、时间点及交互差异均有统计学意义(P<0.0001),术后1个月及术后3个月INFIX组EQ-5D评分均大于外固定支架组,术后1个月及术后3个月INFIX组VAS评分均小于外固定支架组(P<0.05)。结论:INFIX技术联合骶髂关节螺钉治疗Tile B型骨折临床疗效更好,恢复期短,更有利于患者进行早期功能性锻炼,且并发症发生率较低。

Clinical outcomes with large macular holes using the tiled transplantation internal limiting membrane pedicle flap technique

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.

SimWall:a practical user-friendly stereo tiled display wall system

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.

Low-Cost Tiled Display System Architecture with Dynamic Web-Based Management

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.

Tiled-aperture coherent beam combining of two high-power fibre amplifiers

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.

Optical terminal analysis of a multigrating tiled compressor in a PW-class CPA-laser

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.

开放性Tile C型骨盆骨折接受早期前后联合入路切开复位内固定治疗的疗效分析

对开放性Tile C型骨盆骨折患者接受早期前后联合入路切开复位内固定治疗的具体效果做出分析和评价。方法:将我院2020年5月—2021年5月收治的18例开放性Tile C型骨盆骨折患者纳入本研究,所有患者在接受基本的前期处理后均接受骨盆外固定架固定术治疗,经过7—10天后均接受前后联合入路切开复位内固定术治疗。术后常规进行治疗,针对发生污染或是创面感染的情况需要行封闭式负压引流治疗,确保创面愈合。观察并评价本次治疗的临床效果。结果:切开复位内固定手术平均时间为(99.35±8.42)分钟;术中出血量平均为(674.82±152.34)mL;封闭式负压引流治疗次数平均为(4.2±1.2)次,治疗的周期平均为(5.2±1.3)周;培养结果手术后患者均发生了病菌感染,但是感染程度不一,这种情况使患者术后康复时间延长;经过3—12个月的随访,发现患者骨折经过2—4个月后均愈合,愈合时间为(3.2±0.8)个月;骨折复位恢复优良率为100%(18/18),Majeed评分显示功能恢复优良率为83.33%(15/18)。结论:早期前后联合入路切开复位内固定治疗开放性Tile C型骨盆骨折可促进骨折良好愈合,促进功能恢复,是值得在临床中应用的治疗技术。

Implementation of a 3D WebGIS for Dynamic Geo-Referencing of 3D Tiles on the Virtual Globe

Needs for real-time interactive visualization of 3D Tiles for massive 3D content on the web-based virtual globe is rapidly increasing, and to achieve this goal, 3D Tiles needs to be correctly geo-referenced to other geospatial data on a web-based virtual globe. It is possible to generate 3D Tiles from different kinds of spatial data through various software tools. However, due to various factors the 3D Tile datasets are often poorly or not at all geo-referenced. To tackle this issue, we propose a new 3D WebGIS framework that facilitates dynamic geo-referencing 3D Tiles on the CesiumJS virtual globe.

A Sketch-Based Generation Model for Diverse Ceramic Tile Images Using Generative Adversarial Network

Ceramic tiles are one of the most indispensable materials for interior decoration.The ceramic patterns can’t match the design requirements in terms of diversity and interactivity due to their natural textures.In this paper,we propose a sketch-based generation method for generating diverse ceramic tile images based on a hand-drawn sketches using Generative Adversarial Network(GAN).The generated tile images can be tailored to meet the specific needs of the user for the tile textures.The proposed method consists of four steps.Firstly,a dataset of ceramic tile images with diverse distributions is created and then pre-trained based on GAN.Secondly,for each ceramic tile image in the dataset,the corresponding sketch image is generated and then the mapping relationship between the images is trained based on a sketch extraction network using ResNet Block and jump connection to improve the quality of the generated sketches.Thirdly,the sketch style is redefined according to the characteristics of the ceramic tile images and then double cross-domain adversarial loss functions are employed to guide the ceramic tile generation network for fitting in the direction of the sketch style and to improve the training speed.Finally,we apply hidden space perturbation and interpolation for further enriching the output textures style and satisfying the concept of“one style with multiple faces”.We conduct the training process of the proposed generation network on 2583 ceramic tile images dataset.To measure the generative diversity and quality,we use Frechet Inception Distance(FID)and Blind/Referenceless Image Spatial Quality Evaluator(BRISQUE)metrics.The experimental results prove that the proposed model greatly enhances the generation results of the ceramic tile images,with FID of 32.47 and BRISQUE of 28.44.

Synthesis of Ceramic Tiles Reinforced with Addition of Aluminum Particulate Waste

Research conducted on ceramic materials has been investigating the incorporation of solid waste into their formulations,driven by the proper disposal of such waste and the reduction of negative environmental impacts.This study analyzed the effects of adding aluminum powder residue to the physical properties of ceramic masses with the aim of obtaining new formulations for ceramic tiles.The aluminum residue and the standard mass for ceramic tile production were chemically characterized and homogenized to obtain new formulations with the incorporation of 4%,6%,8%,and 10%aluminum powder in the ceramic mass.The specimens were uniaxially pressed and sintered at a temperature of 1,200°C for 2 h,undergoing three different temperatures(100°C,400°C,and 650°C)for 30 min each.They were evaluated for WA(water absorption),RLq(linear shrinkage),SEM(scanning electron microscopy),and TRF(flexural strength)modulus.The results demonstrate that the addition of aluminum powder residue is feasible in the proposed formulations(4%,6%,8%,and 10%),as they enhance the mechanical properties of the ceramics compared to the formulation with 0%residue,at a sintering temperature of 1,200°C.

修复缺陷嫌疑区域的无监督磁瓦表面缺陷检测

磁瓦表面缺陷样本数量少,异常视觉特征分布发散,现有依赖目标特征的有监督检测方法不能有效检测未定义缺陷;磁瓦表面正常纹理呈非均匀且非周期性分布,使得经典重构网络难以准确地重构磁瓦表面正常特征,导致相关无监督检测方法性能低下.为此,采用多头注意力增强的掩码图像修复网络(MIINet),长距离提取图像特征,捕捉全局信息,增强图像修复的能力;引入视觉显著性算法抑制磁瓦表面纹理信息和突显缺陷区域,以便二值化算法精准分割缺陷嫌疑区域;利用MIINet修复待检测图像缺陷嫌疑区域,选用修复前后图像的残差图像和结构相似性实现缺陷检测与缺陷判定.与经典无监督方法相比,修复缺陷嫌疑区域的表面缺陷检测方法的准确率提升了2.36%,F1值提升了1.62%.

基于要素稠度的电子海图矢量瓦片组合构建方法

为进一步提升基于WebGIS技术的电子海图在前端的加载效率,对海图矢量瓦片的划分方法进行深入研究。在考虑要素空间分布稠度的基础上,提出一种海图瓦片的组合格网划分方法。在四叉树划分过程中引入矢量瓦片数据阈值将其改造成非平衡四叉树,作为瓦片划分的第1阶段,在瓦片划分至单瓦片最大数据量小于数据阈值后,通过融合变异系数的二叉树对瓦片进行第2阶段的划分。将组合格网法、原始均匀格网法和改进均匀格网法生成的矢量瓦片数据与试验结果进行对比。研究结果表明,在瓦片第3~第9层级范围内,相对于2种均匀格网法,基于要素稠度的组合格网法生成的矢量瓦片在同一层级的标准差更小,矢量要素在瓦片上的分布更加均衡,在同一视窗范围内,组合格网法生成的瓦片加载时间更短。

莆田地震台铟瓦棒伸缩仪故障分析及维修技术研究

该文论述莆田地震台形变观测仪器SS-Y型铟瓦棒伸缩仪近几年来的故障,从电源、主机、传感器、线路故障等几个方面对故障进行整理、分类、统计。通过故障的表现形式分析故障原因,整理出不同故障曲线形态产生的原因。总结莆田地震台维修经验,结合其他台站经验,针对不同故障给出维修方案,可为其他相关地震台站提供借鉴。