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771.
中国古典园林设计教学模式是中国园林课程体系中的重点内容,而古典园林“形”的塑造”与“意”的升华,及两者之间的有机契合,一直以来都是教学中的核心内容,也是设计中学生较难把控的内容。本文以一份以书法为主题的宋式园林设计为例,将探究式教学模式贯穿设计全过程,复现了设计过程的关键环节。从立意构思为始,在分析宋式园林的空间格局基础上为本课题提供充分的设计依据;以宋代四位书法家的承续关系和艺术风格为线索,探讨其在园林空间形态上的转译方式和意境表达。  相似文献   
772.
    
This paper documents and discusses an investigation into the improved performance grading of asphalt binders that were used in the Canadian Strategic Highway Research Program (C-SHRP) pavement trial in Lamont, Alberta. Binders were assessed for their tendency to reversibly age at low-temperatures. While the correlation between cracking severity and regular AASHTO M320 and MP1a grades was weak (r 2=0.73 and 0.49, respectively), the predictive ability of the BBR method increased significantly when binders were tested after 1, 3 and 8 days of conditioning (r 2=0.94–0.97). Brittle and ductile fracture energies were measured in single-edge-notched bending (SENB) and double-edge-notched tension (DENT), respectively. In the brittle state, the SENB test revealed little difference between the binders. However, in the ductile state, the DENT test revealed significant differences between materials, with binders that showed the least amount of cracking having the highest works of fracture at 0°C.  相似文献   
773.
从设计史的视野来观察,中国园林绘画在中国园林的设计、建造、推广、恢复等过程中,是多种学科与园林艺术设计史相链接的必要桥梁。它不仅是一幅幅静态的图像,而且是蕴含丰富设计理念和文化内涵的动态过程。通过对园林绘画的深入分析,能够考察到园林设计历史的演进、观念的革新及美学思想的变迁。中国园林绘画连接着过去与现在,传统与现代,它在记录设计发展的同时,也启发着当代的设计实践与理论创新。  相似文献   
774.
提出一种简便高效的二元离散粒子群算法.其每个粒子的各元素在新位置取二元值0或1的概率正比于其当前位置、历史最优位置和邻域内历史最优位置的取值,而负比于其前一个位置的取值.它不涉及在离散粒子群算法中难以解释的速度的概念.在算法中引入一个领袖粒子,有效地加快了算法的收敛速度,且没有增加函数的评估计算量.  相似文献   
775.
基于场景几何约束未标定两视图的三维模型重建   总被引:8,自引:1,他引:7       下载免费PDF全文
提出了一种从两幅未标定图象重建场景三维模型的方法 .这种方法充分利用了人造结构场景中大量存在的平行性和正交性几何约束 ,即利用每幅视图中三组互相垂直的平行线 ,计算出 3个影灭点 ,从而对每幅视图进行标定 .对两幅未标定图象 ,从基本矩阵只能得到射影重构 ,如果每幅图象都已标定 ,则可将基本矩阵转化为本质矩阵 .三维重构过程有两个步骤 :先是恢复相机的位置和运动 ;后是用三角测量法计算出点的三维坐标 .对多平面组成的场景进行三维重构实验 ,所得三维模型产生新的视点图象 ,与所观察的场景一致 ,重构的两个平面夹角与实际值相近 ,实验结果表明 ,该算法是行之有效的  相似文献   
776.
    
The essential oil of Syzygium aromaticum (clove EO) and its major ingredients, eugenol, possess many biological activities such as antibacterial, antifungal, and antioxidant properties. Therefore, they have been widely used in traditional and contemporary medicine. In this study, the ingredients of clove EO were identified using GC-MS analysis. The antibacterial and leishmanicidal activities of the total essential oil and eugenol were also investigated. Eugenol (65.41%), trans-caryophyllene (12.6%), eugenol acetate (9.85%), caryophyllene oxide (3.00%), and α-humulene (1.73%) were identified as five major components of clove EO. Additionally, the obtained IC50s of clove EO, 177.66, 300.53, 362.94, and 248.08 μg/mL, against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae, respectively, were lower than those of eugenol with IC50s of 320.80, 692.91, 591.82, and 445.87 μg/mL. However, this difference was not significant, except against E coli. Also, clove EO and eugenol showed proper leishmanicidal effects on promastigotes of Leishmania tropica (180.24 and 233.52 μg/mL) and Leishmania major (654.76 and 517.14 μg/mL). Furthermore, there was no significant statistical difference between the anti-Leishmania effect of EO and eugenol. Clove EO and eugenol showed proper antibacterial and leishmanicidal activities. However, the use of clove EO is preferable than eugenol because of the lower cost and straightforward preparation process.  相似文献   
777.
The Aerosol Robotic Network - Ocean Color (AERONET-OC) instrument located at the Pålgrunden site in Lake Vänern provides values of remote sensing spectral reflectance RRS(λ) since 2008. These in situ RRS(λ) indicated a temporal increase from 2015 at center-wavelengths in the green and red spectral regions. To investigate the environmental and climate processes responsible for this increase, water color trends in Lake Vänern were analyzed considering in situ limnological measurements, meteo-climatic quantities and additionally satellite-derived data products from the Moderate Resolution Imaging Spectroradiometer on board the Aqua platform (MODIS-A). Satellite ocean color RRS(λ) data assessed against in situ RRS(λ) from the Pålgrunden site showed satisfactory agreement at a number of spectral bands. Relying on these validation results, comprehensive statistical analysis were performed using MODIS-A RRS(λ). These indicated periodical changes between 2002 and 2021 with clear minima occurring between 2010 and 2013. The complementary analyses of temporal changes characterizing limological and meteo-climatic quantities, and also relationships between these quantities and RRS(λ), indicated the existence of complex and concurrent bio-geochemical processes influencing water color in Lake Vänern. In particular, significant correlations were observed between RRS(λ) and turbidity, and also between RRS(λ) and total biovolume. Additionally, an early warming of Lake Vänern surface waters was identified since spring 2014. This occurrence could potentially affect the vertical mixing and water exchange between turbid coastal and pelagic waters with implications for phytoplankton phenology.  相似文献   
778.
目的 为增加鸡肉在贮藏期的保鲜效果和保留鸡肉的品质。方法 本文设置未涂膜组、明胶涂膜组和精油-明胶涂膜组的鸡肉样品, 通过测定失重率、色泽、质构等指标评价鸡肉随着贮藏时间的变化; 结合扫描电镜、电子鼻和电子舌观察在相同贮藏条件下鸡肉肌肉组织结构、品质的变化。结果 实验表明, 在25 ℃环境下,随着贮藏时间的延长, 鸡肉的各种指标均发生明显变化, 组织结构亦受到不同程度地破坏, 表明鸡肉的品质逐渐下降。与未涂膜组相比, 精油-明胶涂膜组和明胶涂膜组鸡肉的失重率较低, 有较好的持水力; 色泽保护程度更好; 质地变化较为缓慢; 组织结构保持较完整, 且精油-明胶涂膜组的保鲜效果优于明胶涂膜组。电子鼻、电子舌的数据显示, 与明胶涂膜相比,加入生姜精油的复合明胶涂膜在气味和滋味上更接近新鲜鸡肉,表明精油-明胶涂膜更有利于保持鸡肉的气味和口感。结论 该文可得出明胶涂膜可延长鸡肉的保鲜效果期, 添加精油之后形成的精油-明胶涂膜更有利于保持鸡肉的品质, 为生鲜鸡肉的贮藏提供一种新方法。  相似文献   
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