A semantic vector map-based approach for aircraft positioning in GNSS/GPS denied large-scale environment

Accurate positioning is one of the essential requirements for numerous applications of remote sensing data,especially in the event of a noisy or unreliable satellite signal.Toward this end,we present a novel framework for aircraft geo-localization in a large range that only requires a downward-facing monocular camera,an altimeter,a compass,and an open-source Vector Map(VMAP).The algorithm combines the matching and particle filter methods.Shape vector and correlation between two building contour vectors are defined,and a coarse-to-fine building vector matching(CFBVM)method is proposed in the matching stage,for which the original matching results are described by the Gaussian mixture model(GMM).Subsequently,an improved resampling strategy is designed to reduce computing expenses with a huge number of initial particles,and a credibility indicator is designed to avoid location mistakes in the particle filter stage.An experimental evaluation of the approach based on flight data is provided.On a flight at a height of 0.2 km over a flight distance of 2 km,the aircraft is geo-localized in a reference map of 11,025 km~2using 0.09 km~2aerial images without any prior information.The absolute localization error is less than 10 m.

Application of water loop variable refrigerant flow air-conditioning system in large-scale buildings in northern China

A water loop variable refrigerant flow（WLVRF）air-conditioning system is designed to be applied in large-scale buildings in northern China.The system is energy saving and it is an integrated system consisting of a variable refrigerant flow（VRF）air-conditioning unit,a water loop and an air source heat pump.The water loop transports energy among different regions in the buildings instead of refrigerant pipes,decreasing the scale of the VRF air-conditioning unit and improving the performance.Previous models for refrigerants and building loads are cited in this investigation.Mathematical models of major equipment and other elements of the system are established using the lumped parameter method based on the DATAFIT software and the MATLAB software.The performance of the WLVRF system is simulated.The initial investments and the running costs are calculated based on the results of market research.Finally,a contrast is carried out between the WLVRF system and the traditional VRF system.The results show that the WLVRF system has a better working condition and lower running costs than the traditional VRF system.

Digital Application Objectives and Benefit Analysis of BIM Technology in Large-Scale Comprehensive Development Projects

This paper discusses the digital application and benefit analysis of building information model(BIM)technology in the large-scale comprehensive development project of the Guangxi headquarters base.The project covers a total area of 92,100 square meters,with a total construction area of 379,700 square meters,including a variety of architectural forms.Through three-dimensional modeling and simulation analysis,BIM technology significantly enhances the design quality and efficiency,shortens the design cycle by about 20%,and promotes the collaboration and integration of project management,improving the management efficiency by about 25%.During the construction phase,the collision detection and four-dimensional visual management functions of BIM technology have improved construction efficiency by about 15%and saved the cost by about 10%.In addition,BIM technology has promoted green building and sustainable development,achieved the dual improvement of technical and economic indicators and social and economic benefits,set an example for enterprises in digital transformation,and opened up new market businesses.

Experimental Mode and Vibration Comfort Analysis of High-Rise Glulam Building Floor Structure

In order to better meet the objective requirements of the use safety of the high-rise glulam building floor structure and the living comfort of the residents,the transient excitation,environmental excitation and frequency spectrum identification methods were used to carry out experimental modal test in-site on the three rooms numbered A,B and C of the same glulam structural building.The three rooms have different functions,different floor sizes and different floor supporting structures.The research results have shown that the first-order bending frequency of the floor structure of Room A is 27.50 Hz,the transverse second-order bending frequency is 34.75 Hz,the longitudinal second-order bending frequency is 53.25 Hz,and the first-order torsional frequency is 56.25 Hz.The reinforced wooden beam at the bottom of the floor of Room A increases the transverse stiffness of the floor structure,but does not offset the anisotropy caused by the longitudinally installed glulam floors.The fundamental frequency values of the floor structures of the three rooms numbered A,B,and C are 27.5,13 and 18 Hz,respectively.This has a relatively high innovation and reference significance for integrating the theory of structural dynamic characteristics with the dynamic testing technology,improving the design level of high-rise glulam structure buildings,and improving the living comfort of residents.

Wooden Wall Construction of Traditional Miao Stilted Buildings: A Case Study of Xijiang Miao Village in Guizhou

Wooden walls of traditional stilted buildings of Miao Nationality show outstanding regional characteristics. Taking the well-preserved traditional stilted buildings in Xijiang Miao Village for example, this paper focused on the construction units of the wooden wall, and the hierarchy of wooden wall construction, concluded spatial forms of the wooden wall, in order to explore the indigenous construction culture in the wooden wall system, protect and inherit the culture; seek for the ways of expressing national and regional characteristics in the modern architectural designs of relevant cultural regions.

A Case Study of VäxjöMunicipality’s Actions to Increase the Construction of Wooden Multi-family Buildings

Sweden has a housing shortage,which the Swedish authorities expect to continue until 2025.Producers of wooden multi-family houses have a relatively small market share in comparison to traditional building materials.The limited capability to fulfil the increased building demand also restricts the possibilities for development towards innovation,bio-economy and sustainability.The municipalities in Sweden have responsible for planning of the building development in their region based on their projected requirements and strategies.Combining this with a desire to develop sustainable building solutions based on wood increases the complexity.Currently,public building developments are achieved through the public procurement act or the land allocation activity,dependent on their development strategy.This normally involves the development of local strategies regarding,e.g.design,material choice and geographical development.By identifying market drivers enables improved market entry activities related to public building initiatives using wood-based solutions.Hence,by improving transparency in the land allocation activity generate enhanced possibilities for the companies to respond successfully to the requests submitted by the municipalities.This knowledge is used to better understand the required strategic development for the companies,the government and the municipalities to increase the use of sustainable building materials in Swedish multi-family housing projects.

Generating hourly electricity demand data for large-scale single-family buildings by a decomposition-recombination method

Household electricity demand has substantial impacts on local grid operation,energy storage and the energy per-formance of buildings.Hourly demand data at district or urban level helps stakeholders understand the demand patterns from a granular time scale and provides robust evidence in energy management.However,such type of data is often expensive and time-consuming to collect,process and integrate.Decisions built upon smart meter data have to deal with challenges of privacy and security in the whole process.Incomplete data due to confiden-tiality concerns or system failure can further increase the difficulty of modeling and optimization.In addition,methods using historical data to make predictions can largely vary depending on data quality,local building envi-ronment,and dynamic factors.Considering these challenges,this paper proposes a statistical method to generate hourly electricity demand data for large-scale single-family buildings by decomposing time series data and recom-bining them into synthetics.The proposed method used public data to capture seasonality and the distribution of residuals that fulfill statistical characteristics.A reference building was used to provide empirical parameter settings and validations for the studied buildings.An illustrative case in a city of Sweden using only annual total demand was presented for deploying the proposed method.The results showed that the proposed method can mimic reality well and represent a high level of similarity to the real data.The average monthly error for the best month reached 15.9%and the best one was below 10%among 11 tested months.Less than 0.6%improper synthetic values were found in the studied region.

结构健康监测系统在木结构古建筑中的应用

文物木结构古建筑是一个国家文化的重要组成部分,代表着民族文化的自信与传承。然而由于长时间受到环境和人为侵蚀,木结构古建筑易遭到损坏。为更好地保存好木结构古建筑以及其代表的文化内涵,对其结构安全监测提出了迫切的需求,近年来对木结构古建筑的安全监测方法也得到了快速的发展。分别介绍了虚拟重建、红外热成像、地面激光雷达、超声波监测、光纤传感等技术的原理及在木结构古建筑监测中的应用,并总结了其各自的优势与劣势。针对木结构古建筑采光不足问题,总结了光导系统,尤其是光纤光导照明系统对自然光的引入,该类照明系统具有清洁、安全的特点,避免了烛火、电类照明系统为木结构古建筑带来的火灾风险。

木材老化对古建筑木梁抗弯性能的影响分析

为研究木材老化对古建筑木梁抗弯性能的影响,分析了木材的老化机理,采用等效截面法并结合国内木梁老化深度经验公式,提出了老化木梁抗弯承载力退化模型,并对某古建筑的木梁进行了承载力退化评估。对未老化与老化木梁进行了单调加载数值模拟,并通过试验验证了模型的合理性;在此基础上,进一步分析了老化均匀度与老化深度对木梁抗弯性能的影响。结合《木结构设计标准》(GB 50005—2017)中受弯构件的承载力计算公式,提出了考虑老化影响的木梁抗弯承载力折减系数计算公式。结果表明:老化对木梁抗弯承载力的影响与老化均匀度呈线性相关,与老化深度呈一元二次多项式关系。老化深度越深且老化均匀度越大,木梁承载力越低。

藏式传统木结构民居解构与营造研究

文章采用ICP算法结合最优最小二乘法原理针对高度变形的藏式传统木结构民居展开定量化测绘,并利用逆向技术重构原生模型。结果表明:ICP算法结合最优最小二乘法原理可以有效提升多源点云数据融合精度,能够为藏式传统木结构民居研究提供可靠、真实的本底数据,实现了对藏式传统木结构民居的结构解析、实景复原、建筑形态与形制模式及要素特征等肌理阐释。该方法可为其他地区传统建筑的研究与全要素保护提供方法借鉴。

木结构斗拱出挑层数对建筑抗震性能的影响

木结构古建筑是世界建筑史的重要组成部分,目前的研究大部分集中在结构整体的抗震性能上,或者单独对构件的受力机理进行分析,主要的研究构件包括斗拱、柱、梁架等,但是在构件对整个结构抗震性能的影响方面研究较少。以殿堂型结构中的斗拱为研究目标,利用ANSYS和ABAQUS软件对其展开模态与动力时程分析。通过对不同层数的斗拱进行分析比对,总结出斗拱层数变化对其抗震性能的影响。结果显示,在地震波作用下两模型柱脚和柱顶位移相差不大,但屋脊位置的位移量五踩斗拱模型比三踩斗拱模型多40%,五踩斗拱的柱顶加速度比三踩斗拱的柱顶加速度小23.02%,五踩斗拱的屋脊加速度比三踩斗拱屋脊小24.27%,证明在一定范围内斗拱层数的增加有利于结构的耗能减震。

“丈八八”形制影响下的大木构架尺度表达——以木格倒苗寨及土家大寨传统民居为例

川渝地区苗族、土家族木构技术中传承因袭的“丈八八”形制,是将“八”为尾数的数字运用于传统建筑尺寸设计的地方营造习俗。这种以简明易记的尺寸数字把握建筑空间尺度的营造习俗,是地方传统建筑营造技术的经验积累和智慧总结,也是传统建筑模数制度的发展延续和重要呈现。本文以叙永木格倒苗寨及秀山土家大寨传统民居为例,通过详实的实地调研和匠师访谈,探究“丈八八”形制在传统大木技术中的具体表达机制,分析不同地域间“丈八八”形制的关联和差异,并借此阐释川渝苗族、土家族传统建筑营造的一些重要规律和特征。

木结构榫卯节点力学性能分析与加固方法综述

古木建筑中广泛采用的榫卯连接具有出色的耐久性和抗震性能。然而各种因素对榫卯造成的劣化和损伤会威胁到整体结构的安全。因此,探究榫卯的力学特性、损坏类型、修复方式对保护木结构建筑具有重要意义。首先,介绍了榫卯的历史渊源,根据朝代划分简要梳理了各类榫卯的发展历程,应用情况。其次,详细分析了榫卯节点的力学性能和耗能减震机理,概述了其破坏原因和形式。接着,根据榫卯的破坏形式,重点从传统材料、新型材料两个方面对加固方法进行归纳,从实用性及美观性等方面比较各种加固方法及其适用范围,并对近年来工程案例分类总结。最后,本文对未来榫卯节点破坏的预防,修复和监测提出了相关展望,以期为未来研究和实践提供有益的参考。

面向木结构建筑的绿色性能评价指标体系研究

木结构建筑因其卓越的绿色性能备受关注,然而我国现有的评价标准对这种特殊建筑的评价方面不够系统完善。在综合分析木结构建筑研究概况及现有评价体系的基础上,采取扎根理论建立评价指标体系,通过运用德尔菲法对指标进行优化;采用主客观组合赋权法对各个指标在整体模型中的权重赋权,确保指标权重的科学性、合理性。通过运用扎根理论和德尔菲法的深入分析和专家反馈,细化和优化评价指标,形成木结构建筑绿色性能评价指标体系,包括6个一级指标、31个二级指标,并根据权重分析得到了指标体系对木结构建筑发展的启示,提出了针对性的发展建议,为未来木结构建筑评价提供了一套可靠的评价指标体系。

我国木构建筑研究现状、热点及前沿——基于CiteSpace文献计量分析

基于CNKI和WOS数据库的(2003-2023年)中国木构建筑专题文献,采用文献计量软件CiteSpace进行数据可视化分析,旨在揭示我国木构建筑研究的现状、热点及前沿趋势。结果表明:我国木构建筑研究呈现出增长的态势。研究领域热点涵盖抗震性能、榫卯结构、仿木构、侗族建筑、梁思成及营造学社等议题;我国木构建筑研究历程可划分为三个阶段:宏观阶段、具体深化阶段、传承应用与多学科交叉阶段。未来的研究中,少数民族及传统民居的多学科交叉木构建筑研究是发展趋势和前沿。

古建用落叶松木材物理力学性能预测及其影响因素

为实现对木结构古建筑的预防性保护,有必要对木构件的材质性能进行及时有效的预测和评价。采取小试样-缩尺-足尺递进的方式,将微钻阻抗仪和应力波检测等无损检测方法与实验室物理力学性能测试相结合,构建并检验了落叶松木材物理力学性能与微钻阻抗值和波阻模量关系预测模型,进而提出了古建用落叶松木材物理力学性能的现场无损检测分析方法。研究结果表明:落叶松小试件密度与微钻阻抗值呈现明显的线性正相关关系,木材密度与微钻阻抗值线性方程相关系数为0.91;落叶松小试样顺纹抗压强度、抗弯强度及抗弯弹性模量与波阻模量呈现较明显的线性正相关关系,木材顺纹抗压强度、抗弯强度、抗弯弹性模量与波阻模量线性方程相关系数分别为0.86,0.74,0.74;通过微钻阻抗仪和应力波检测可推算落叶松木材物理力学性能。利用小试件测试数据所建立的预测方程进行落叶松大试件物理力学性能推算存在一定的误差,其缩尺试件密度和顺纹抗压强度预测值与实际值平均偏差分别为12%和16%,足尺试件密度和顺纹抗压强度预测值与实际值平均偏差分别为16%和17%。现场预测应同时考虑测试路径因素,自心材至边材区域,落叶松木材密度、顺纹抗压强度、微钻阻抗值沿径向表现为增大趋势,外层微钻阻抗值比整体平均微钻阻抗值大4%~16%。在古建筑木构件强度检测评估中,应进行木构件的整体微钻检测;若条件所限无法进行整体检测时,应针对不同树种的径向变化规律进行微钻阻抗值的修正。

辽宁奉国寺彩绘泥塑木骨架生物病害研究

辽宁义县奉国寺的彩绘泥塑群中多尊泥塑发生倾斜,初步勘察为木骨架糟朽导致。为确认木骨架糟朽原因,经过现场勘察,采集糟朽木骨架木材、进行树种鉴定、微生物分离和甲虫尸体鉴定。结果显示:两彩绘泥塑木骨架样品分别为硬木松(Pinus sp.)和杨木(Populus sp.);真菌多样性测序结果表明子囊菌门霉菌为优势真菌,从糟朽木材中分离到一株曲霉(Aspergillus sp.),未见其他腐朽菌;虫体经鉴定为鞘翅目象甲科、窃蠹科、皮蠹科和拟步甲科昆虫。辽宁位于木材腐朽危害中等风险区域(D2),分析认为木骨架糟朽的原因主要为窃蠹和象甲科害虫危害导致,根据甲虫的侵染途径和生长特性,推断木骨架木材在应用之初或者维修替换的新木材未进行预处理,没有杀灭虫卵导致虫卵孵化为幼虫,底部被蠹虫幼虫蛀空导致倾斜。经进一步对奉国寺建筑木构件勘察发现部分柱、梁等构件也出现直径3 mm左右蠹虫羽化孔,说明彩绘泥塑所处的古建筑木构也存在类似的虫害。本研究揭示了窃蠹和象科甲虫对彩绘泥塑的破坏影响,说明了彩绘泥塑木骨架与古建筑木构件在加工使用前进行预防性保护的重要性,为彩绘泥塑的生物病害预防和维修工程中木材防虫害预处理提出了建议。

控制、设计、统筹、中介--基于社会网络的《工程做法》大木作要素研究

清工部《工程做法》作为清代官式建筑范式源本,是解读木大作设计原法的根本。但由于传统分析方法难以理清其记载的各构件尺寸之间的庞杂关系,故本文首次利用社会网络分析方法,确定其卷一大木范式的节点与关系并以此构建出大木作尺寸关系网络,科学量化分析网络整体特征,以中心度指标分析各尺寸于关系网络中的联系与作用,探究出籍本暗含的尺寸灵活特性,总结并阐释其中具备控制、设计、统筹、中介属性的四类要素,并提出清代官式建筑大木作尺寸“变化”及尺寸间“权衡”的思考。以期挖掘清代官式建筑大木作设计原法,科学修正长期以来程式化与标准化的清代官式建筑认知,并为同类古代文献的进一步研究提供创新思路,为中国文化基因的传承表达贡献力量。

基于BIM技术的渝东南木构建筑数字化保护

渝东南木构建筑保护在现代化发展和多元文化的冲击之下面临诸多挑战,随着数字化中国建设的推进和科学技术的发展,为木构建筑保护提供了新的机遇。建筑信息模型(BIM)技术是以建筑工程相关信息数据为基础,进而衍生为建筑信息模型的集成管理技术,贯穿建筑的全生命周期。文章通过将BIM技术特性与渝东南木构建筑保护相结合,以期为渝东南木构建筑保护探寻数字化应用的保护策略。

防火涂料对木结构模型的火灾防护效果研究

为研究防火涂料对木结构建筑的防护效果,提升古建筑在火灾中的安全性,本文通过搭建缩尺寸模型进行对比试验。研究不同火源工况下,有无防火涂料在火蔓延、温升特性及灼烧痕迹方面的差异。与油盘火源相比,木垛火源引燃周围木板所需的时间更长。防火涂料在延缓火势蔓延、降低复燃概率及减小火焰灼烧面积方面均有显著效果。试验为改进和完善古建筑消防安全中被动防火技术的应用提供了基础数据及参考。