利用LIDAR技术获取大比例尺DEM应用实践

以秦皇岛市航测1∶2000数字正射影像图（DOM）、数字高程模型（DEM）、数字线划图（DLG）项目为例,阐述了利用机载激光雷达（LIDAR）技术获取大比例尺数字高程模型（DEM）的方法,分析了应用实践中的一些问题,展望了今后的应用前景。     

数字高程模型(DEM)的构建及其应用

数字高程模型(DEM)是一定区域范围内规则格网点的平面坐标及其高程的数据集或者是经、纬度和海拔高度的数据集。DEM用途广泛,数字地球、数字城市、数字区调等工作以及虚拟现实三维可视化都需要高精度的DEM支撑。本文分析了DEM的构建方法及利用地形图生成的DEM的技术路线和数据转换的问题,论述了DEM在数字区调中的应用,实践证明,该技术在一定程度上解决了高原区调面临的难题,为地质工作提供了一种新途径。     

A design supporting simulation system for predicting and evaluating the cool microclimate creating effect of passive evaporative cooling walls

As a passive cooling strategy to control increased surface temperatures and create cooler urban environments, we have developed a passive evaporative cooling wall (PECW) constructed of pipe-shaped ceramics that possess a capillary force to absorb water up to a level higher than 130 cm. The current paper presents a simulation system to predict and evaluate microclimatic modifying effects of PECWs in urban locations where PECW installation is under consideration at the design stage. This simulation system is composed of a CFD simulation tool and a 3D-CAD-based thermal simulation tool. Simulation methodology of coupling the two simulation tools was developed and described in this paper. Numerical models for simulating surface temperatures and evaporation of PECWs were proposed based on analysis results of experimental data. Validation of the proposed numerical models was confirmed by comparing simulated results with measured data. In order to demonstrate the applicability of the proposed simulation system, a case study was then performed to predict and evaluate the microclimate in a rest station where PECWs were assumed to be installed. Spatial distributions of air temperature, airflow, moisture and surface temperature in the rest station were simulated under a sunny weather condition in the summer of Tokyo. Furthermore, thermal comfort indexes (mean radiant temperature and new standard effective temperature) were used to evaluate thermal comfort in the human activity spaces of the rest station. Simulation results show that this simulation system can provide quantitative predictions and evaluations of microclimatic modifying effects resulting from the application of PECWs.     

Exergetic performance assessment of a solar photovoltaic thermal (PV/T) air collector

In this paper, an attempt is made to evaluate the exergetic performance of a solar photovoltaic thermal (PV/T) air collector. A detailed energy and exergy analysis is carried out to calculate the thermal and electrical parameters, exergy components and exergy efficiency of a typical PV/T air collector. Some corrections are done on related heat loss coefficients. An improved electrical model is used to estimate the electrical parameters of a PV/T air collector. Further, a modified equation for the exergy efficiency of a PV/T air collector is derived in terms of design and climatic parameters. A computer simulation program is also developed to calculate the thermal and electrical parameters of a PV/T air collector. The results of numerical simulation are in good agreement with the experimental measurements noted in the previous literature. Finally, parametric studies have been carried out. It is observed that the modified exergy efficiency obtained in this paper is in good agreement with the one given by the previous literature. It is also found that the thermal efficiency, electrical efficiency, overall energy efficiency and exergy efficiency of PV/T air collector is about 17.18%, 10.01%, 45% and 10.75% respectively for a sample climatic, operating and design parameters.     

Determination of the optimum tilt angle of solar collectors for building applications

Solar energy technologies offer a clean, renewable and domestic energy source, and are essential components of a sustainable energy future. This paper deals with the determination of the optimum tilt angle of solar collectors for building applications. The optimum angle is calculated by searching for the values for which the total radiation on the collector surface is a maximum for a particular day or a specific period. An application of the model is done using the experimental data measured for Izmir in Turkey. The best orientation for solar collectors in Izmir is due south. For increasing the utilization efficiency of solar collectors, it is recommended that, if it is possible, the solar collector should be mounted at the monthly average tilt angle and the slope adjusted once a month.     

设计企业数字化转型研究与实践

近年来,数字化转型随着我国数字经济的不断深化以及因疫情所带来数字化应用的发展,已经上升为企业生存与发展的重中之重。但很少有企业尤其是处在信息化水平相对薄弱的工程设计企业,能真正想清楚这几个问题:数字化转型是什么？该如何转？数字化转型与信息化、数字化的关系是什么？基于此,本文希望能帮助读者回归事物本质,厘清思路,真正弄明白数字化转型的底层逻辑与价值诉求,以“长期主义、价值共生”的理念探究工程设计企业数字化转型之路。       

Life cycle cost assessment of building integrated photovoltaic thermal (BIPVT) systems

The present paper deals with an analysis of the building integrated photovoltaic thermal (BIPVT) system fitted as rooftop of a building to generate electrical energy higher than that generated by a similar building integrated photovoltaic (BIPV) system and also to produce thermal energy for space heating. A thermodynamic model has been developed to determine energy, exergy and life cycle cost of the BIPVT system. The results indicate that although the mono-crystalline BIPVT system is more suitable for residential consumers from the viewpoint of the energy and exergy efficiencies, the amorphous silicon BIPVT system is found to be more economical. The energy and exergy efficiencies of the amorphous silicon BIPVT system are found to be 33.54% and 7.13% respectively under the composite climatic conditions prevailing at New Delhi. The cost of power generation is found to be US $ 0.1009 per kWh which is much closer to that of the conventional grid power.     

基于历史游径视角的京西古道保护与发展研究

京西古道是在永定河河谷、西山山隘、沟谷等地形的基础上自发形成的古代交通系统。从历史游径视角分析其特征具有功能主导聚落性、地形地貌的可控性和文人历史的游观性等。基于数字高程模型分析京西古道的地形空间特性,其游径功能、空间与地貌特征密切相关,且随高程呈现出一定分布规律。进而提出京西古道保护与发展的方法。     

The predictions of infection risk of indoor airborne transmission of diseases in high-rise hospitals: Tracer gas simulation

The spread of diseases from infected patients within hospitals is resulting in many human casualties. If a virus were to be transmitted through uncontrolled air movement within a hospital and were then to infect other patients or healthy visitors, it would be impossible to contain the spread of the disease. The purpose of this paper is to apply reliable boundary conditions based on previous studies in order to analyze the airflow pattern caused by the stack effect in high-rise hospitals. An analysis was carried out on the vertical airborne transmission of viruses according to the location of the infected patients. The horizontal airborne transmission based on the characteristics of the supply air diffuser and return air grille was also analyzed by using the multi-zone airflow simulation and tracer gas (CFD) simulation. In addition, this paper explored solutions to prevent the spread of airborne pathogenic bacteria by analyzing various alternatives of HVAC systems and basic data on ventilation system planning for high-rise hospitals.     

通往风景园林行业的BIM之路——数字化竖向设计教育

随着全球建造业向数字化全面转型,建筑信息模型(BIM)的教学将是未来几年风景园林设计与实施的重要主题。介绍了风景园林专业BIM的教学方法和数字化竖向设计及其应用在BIM场地设计项目中的重要性。数字化竖向设计是实现BIM的途径。风景园林教育必须在其教学中讲解BIM建模方法和过程。     

基于BIM的光伏建筑集成化设计与分析平台

由于缺乏集成建筑设计与光伏设计于一体的光伏建筑一体化设计分析平台,光伏建筑的设计通常被分为建筑设计与光伏设计两个割裂过程。在建筑设计过程中,光伏仅仅被认为是图形元素,而在光伏设计过程中,常常忽略了建筑对于光伏系统阴影辐照影响。这样的模型割裂使得设计人员很难做到真正的光伏建筑一体化设计。提出构建基于建筑信息模型(BIM)的光伏建筑集成化设计与分析平台,通过在建筑设计软件中扩展光伏组件的BIM模型,融入电气特性,实现光伏建筑集成化设计;提供光伏系统的集成分析优化功能,直接利用光伏建筑BIM模型,实现了包括阴影辐射分析和光伏电气分析在内的多种分析功能。由于基于BIM模型,这些分析过程无需任何手动建模过程,实现了设计与分析的无缝融合。通过某具体变电站案例应用,实现光伏系统投入减少11.7%,电能损耗降低5%,证明本平台可以有效改进光伏建筑的设计。     

数字地价模型建立过程中的插值方法研究——以上海内环线地区为例

对反距离加权平均(IDW)插值法和克立格(Kriging)插值法两种空间插值方法在数字地价模型(DLPM)建立过程中的插值效果进行比较研究,采用上海内环线地区内的实际样本点数据进行有关实证分析。利用空间插值软件Surfer8.0对上海内环线地区内地价样本点使用上述两种不同的插值方法插值生成不同的插值结果文件,再利用GIS软件MapInfo7.5把插值结果文件生成数字地价栅格专题图,最后用随机选取的验证点对不同的插值结果进行比较分析。研究结果表明:反距离加权平均(IDW)插值法比克立格(Kriging)插值法插值效果更佳,其插值结果更加接近实际地价分布,而且,反距离加权平均(IDW)插值法属于确定性插值法,也简单、易操作,样本点处的插值结果也可以更好的接近样本点的实际地价值,使得数字地价模型(DLPM)的建立更加可靠、可行。     

基于任意曲线的地面属性区模型建模方法

介绍了地表属性区建模和综合数字地面模型的基本概念,提出了一种具有高度灵活性的基于自由曲线定义的地面属性模型的实测同步建模方法及其算法实现原理,还介绍了这种方法在实测建立高等级公路带状数字地面模型中的应用。     

Model-based evaluation of competition between polyphosphate- and glycogen-accumulating organisms

Many studies show that glycogen-accumulating non-polyphosphate organisms (GAOs) can compete with polyphosphate-accumulating organisms (PAOs) for organic substrate under anaerobic conditions and may indeed cause the deterioration of enhanced biological phosphorus removal (EBPR) systems. Understanding their behaviors in an anaerobic/aerobic (A/O) system at different operational conditions is essential in developing control strategies that ensure EBPR. A model-based evaluation of competition between PAOs and GAOs under different operational conditions was presented in this study. At 30 degrees C and a 10-day sludge age, the dominance of GAOs in the A/O sequencing batch reactor (SBR) was strongly dependent upon their considerable kinetic advantage in anaerobic acetate uptake. At 20 degrees C and a 10-day sludge age, the kinetic advantage of GAOs in anaerobic acetate uptake could be less, compared to that at 30 degrees C and a 10-day sludge age, leading to the relative dominance of PAOs and a stable phosphorus removal in the A/O system. At 30 degrees C and a 3-day sludge age, the parameters responsible for determining the aerobic distribution of anaerobically stored X(PHA) for both PAOs and GAOs, other than kinetic parameters of anaerobic acetate uptake, are important for them being dominant in the A/O SBR. In a situation when the q(PHA,P) value is lower than q(PHA,G) but comparable, PAOs may still be dominant in the A/O SBR, presumably because their aerobic conversion fraction of biomass production from PHA was higher than that of the GAOs.     

Calculation of optimal thermal load of intermittently heated buildings

A building is permanently in thermodynamic non-equilibrium due to changing weather, free gains and indoor temperature set-point. Load calculation in dynamic conditions is an essential goal of building energy simulation. This paper demonstrates that the load calculation is a control problem. Supposing that the thermal model of the building is linear and that the model of the building, the weather conditions and occupational program are known in the design stage, the paper proposes an unconstrained optimal control algorithm which uses feed-forward to compensate the weather conditions and model predictive programming (MPP) for set-point tracking. MPP is obtained by modifying the dynamic matrix control (DMC), a variant of model predictive control (MPC).The peak load depends on the set-back time of the indoor temperature: smaller the set-back time, larger the peak load, but smaller energy consumption. Then, the choice of the weighting coefficients in the model predictive programming may be done on economical considerations.