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1.
Street trees provide shade and increase human thermal comfort during hot summer. In this study, we investigated the spatial distribution of shade provision of street trees in Boston, Massachusetts. The sky view factor (SVF), which influences the solar radiation to the ground and affects human thermal comfort, was used to indicate the contribution of street trees on shade provision. Google Street View (GSV) panoramas were used to calculate the photographic method based SVF (SVFP), with the consideration of all kinds of obstructions within street canyons. A building height model was used to calculate the simulation based SVF (SVFs), with consideration of obstruction of building blocks only. Considering the fact that street trees and building blocks are the two major obstructions of radiation within street canyons, therefore, the difference between the two SVF estimation results can be considered as the shade provision of street trees. The results show that street trees help to decrease the SVF by 24.61% in Boston, Massachusetts. The shading level varies spatially in the study area. Generally, the southwestern area has much higher shading level than the north and the east. We further explored the shading variation among different socioeconomic groups in the study area. Result shows that Hispanics tend to live in neighborhoods with lower shading level. This study can help to provide a reference for future urban greening projects for global climate change adaption.  相似文献   
2.
韦雨涓 《广东园林》2020,42(5):92-96
欧阳修自幼与园林结缘,仕宦四十年,所到之处植花造园,笔耕不辍,留下数座园林景观、二十多篇园亭记及百余首园林诗词,撰写了现存最早的牡丹专著《洛阳牡丹记》,为后人研究园林提供了珍贵的史料。欧阳修的园林活 动和园林书写与其宦海沉浮、文学创作紧密相关。欧阳修热爱但不耽溺于园林,其崇尚自然、开放自适,不拘于形,不役于物的园林观,拓宽了园林审美的视域,启发了后人对“物”的审美思考,为园林理论注入了新鲜血液。欧阳修进一步打开了园林的大门,推动了园林的开放,为园林的繁荣与普及做出贡献。  相似文献   
3.
农业机器人移动平台的研究现状与发展趋势   总被引:1,自引:0,他引:1  
简要介绍了农业机器人在农业信息化智能化中的重要地位以及机器人移动机构的类型,综述了当今农业机器人移动平台的研究现状,展望了今后这一领域的发展趋势。  相似文献   
4.
通过对水特性及水的景观效应的分析和对现代园林中各类水景工程的景观效应及各自的特色,综合阐述了现代园林中水景工程的作用和特点。  相似文献   
5.
根据天津市各区县森防站的生产管理需求,研发了天津市林业有害生物管理信息系统。主要介绍了相关功能的实现方法与实现过程,并重点阐述了该系统在功能设计、开发和实现方法上的创新点——标本管理模块和预测预报模块。目前,该系统已经在天津市各区县森防站得到了实际应用,并取得了良好的效果。  相似文献   
6.
本文基于景观生态学原理提出大学校园生态景观的规划设计理念。以沈阳建筑大学为例,阐述校园生态景观的形成基础及过程,强调大学校园规划中功能、景观、生态的和谐统一对校园内自然生态环境的保护,乃至周边整体环境质量的提高有着至关重要的作用,以指导我国新形势下的新一轮校园规划的展开。  相似文献   
7.
ArcView GIS在林业制图方面的应用   总被引:1,自引:0,他引:1  
应用地理信息软件ArcView GIS在林业制图方面的二次开发,编制出适用的应用程序,操作简单易行,提高了生产效率,为形成规模生产、实现林业制图自动化程度奠定基础。  相似文献   
8.
Frozen bread dough: Effects of freezing storage and dough improvers   总被引:1,自引:0,他引:1  
This review focuses on the effects of freezing storage on the microstructure and baking performance of frozen doughs, and provides an overview of the activities of dough improvers, including emulsifiers, hydrocolloids and other improvers used in frozen dough applications. The overall quality of bread baked from frozen dough deteriorates as the storage of the dough at sub-zero temperatures increases due to several factors which are discussed. Lipid-related emulsifiers such as diacetyl tartaric acid esters of mono and diglycerides and sucrose esters employed as anti-staling agents, dough modifiers, shortening sparing agents, and as improvers for the production of high-protein bread have also been employed in frozen doughs. Hydrocolloids are gaining importance in the baking industry as dough improvers due to their ability to induce structural changes in the main components of wheat flour systems during breadmaking steps and bread storage Their effects in frozen doughs is discussed. Other dough improvers, such as ascorbic acid, honey and green tea extract, are also reviewed in the context of frozen doughs.  相似文献   
9.
种子包衣是防治病虫害、提高作物产量的重要途径之一。综述了近年我国作物种衣技术的发展、种衣剂的种类及种衣剂应用效果等方面的最新研究与应用,提出了种衣剂在苎麻种子上应用的研究方向。  相似文献   
10.
《Plant Production Science》2013,16(4):498-506
Abstract:

The previous work revealed that the polarization of light reflected from heading wheat canopies allowed the detection of changes in the canopy structure, i.e., the leaf inclination angle. Accordingly, in order to improve measurement accuracy in this study we examined the effects of the solar zenith angle (= 90º–solar elevation) and weather conditions at the time of polarization measurements for the light reflected from wheat canopies that were fertilized by different means. We measured polarization in the 660 nm spectral band from the heading canopies of wheat, which were grown in plots fertilized with a basal dressing and then top-dressed at the jointing and booting stages. The radiometric measurements were carried out at various solar zenith angles: 22º–41º on two proximal days, one overcast and the other clear. An empirical method for the adjustment of view zenith angle, based on the solar position at the time of measurement, was effective for the measurement of the degree of polarization (i.e., ratio of the polarized part of reflected light to the total reflected light energy) to eliminate interference due to the change in solar zenith angle. Although the mean values of polarization degree measured in overcast conditions were significantly lower than those measured under clear conditions, the plots top-dressed at the jointing stage could be detected via the polarized reflected light measured under both conditions of illumination.  相似文献   
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