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Epigenetic marks are modulated by gender and time of the day in the hippocampi of adolescent rats:a preliminary study
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作者 Viviane Rostirola Elsner Laura Reck Cechinel +2 位作者 Louisiana Carolina Ferreira de Meireles Karine Bertoldi Ionara Rodrigues Siqueira 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第12期2160-2163,共4页
Although the involvement of gender in epigenetic machinery in peripheral tissues during the neonatal period has been suggested, the gender-related epigenetic profile of brain areas during the adolescent period is rare... Although the involvement of gender in epigenetic machinery in peripheral tissues during the neonatal period has been suggested, the gender-related epigenetic profile of brain areas during the adolescent period is rarely exploited. Furthermore, the influence of time of day on hippocampal acetylation marks has been demonstrated in young adult and aged rats; however, there are no studies reporting epigenetic changes in the adolescent period. Therefore, this study aimed to investigate the effects of gender on hippocampal DNA methyltransferase 1 content and histone deacetylase(HDAC) activity of adolescent rats at different time points, specifically early morning and afternoon. Both epigenetic markers increased significantly in the hippocampi of female rats compared to the male group, an indicator of reduced transcriptional activity. In addition, HDAC activity during the early morning was higher compared to afternoon groups in both male and female rats, while DNA methyltransferase 1 content was not altered by the time of day. Our findings demonstrate that hippocampal DNA methylation and histone acetylation status can be influenced by gender during the adolescent period, while the time of the day impacts HDAC activity. 展开更多
关键词 adolescent rats DNA methyltransferase 1 histone deacetylase HIPPOCAMPUS time of the day GENDER epigenetic marks
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Incubation strategies of the Black-necked Crane(Grus nigricollis) in relation to ambient temperature and time of day
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作者 Lixun Zhang Bei An +5 位作者 Meilin Shu Changming Zhao Xiaojun Yang Yila Suo Yongjun Se Xilite Dabu 《Avian Research》 CSCD 2017年第3期147-155,共9页
Background: The behavior of cranes reflects many of their survival strategies, but little has been known of the incubation strategies of cranes, in which both parents share incubation duties, in response to cold tempe... Background: The behavior of cranes reflects many of their survival strategies, but little has been known of the incubation strategies of cranes, in which both parents share incubation duties, in response to cold temperatures in alpine environments. The lack of information may restrict the effective conservation of the threatened Black-necked Crane(Grus nigricollis), a biparental bird nesting in high elevation wetlands.Methods: We directly observed and used infrared video cameras from 2014 to 2015 to study the incubation behavior and quantitatively measured the frequency and details of egg turning behavior in the Black-necked Crane at the Yanchiwan National Nature Reserve in western Gansu Province, China.Results: At lower ambient temperatures in the morning, crane parents spent more time on the nest with less recess frequency and prolonged on-bout duration, while at higher temperatures around noon, the parents had more frequent recesses from incubation and shorter periods between nest exchanges. They adjusted the amount of time incubating by varying the recess frequency and the length of on-bout duration. Mean nest attendance and egg turning frequency of females were significantly higher than those of the males. The nest attendance and on-bout duration of females showed a significantly negative relationship with those of males. The two parents responded differently to the change of temperature. Females spent more time on the nest at lower morning temperatures, while males increased their time on the nest at higher temperatures after noon. Higher incubation recess frequency and egg turning frequency were observed at noon, probably because parents spent more time foraging, taking advantage of the lower egg cooling rate.Conclusion: Both Black-necked Crane parents in the alpine environment adjusted their behavior in response to the thermal requirements of eggs and the weather conditions experienced. Our findings demonstrate that parents of this species incubated in different but complementary ways and efficiently enhanced egg care in a dynamic environment, so as to maximize benefits from the warm portion of the day and the intense solar radiation while minimizing the cost of rewarming eggs and the risks of cooling eggs. 展开更多
关键词 time of day Ambient temperature Egg-turning frequency On-bout duration Nest attendance Recess frequency Biparental bird
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三个“时代”—age、times、days
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作者 郭燕萍 《语言教育》 1996年第2期57-57,共1页
《大学英语》精读第一册第九单元引言的开头即是“Throughout the ages…,”(“各个时代……”);课文的第三行又出现这样的短语:“In ancient times…,”(“在古代……,”);第二单元课文最末一句:“Moreover,in the modernage…,”(“此... 《大学英语》精读第一册第九单元引言的开头即是“Throughout the ages…,”(“各个时代……”);课文的第三行又出现这样的短语:“In ancient times…,”(“在古代……,”);第二单元课文最末一句:“Moreover,in the modernage…,”(“此外,在现代……,”),这三句中的 age 和 times 都表示“时代”,除此以外,days 也表示“时代”,这里将三个“时代”联系起来看,便于记忆、掌握、运用。这三个名词作“时代”解释时,皆为可数名词,age 通常用单数,time和 day 通常用复数。 展开更多
关键词 《大学英语》 ancient age dayS timeS 维多利亚女王 史前时期 艰难时世 斯图亚特 经济危机时期
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Wedding Ceremony EncounteredThree Times a Day
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作者 SuShan PhotosbyZhangYan 《China & The World Cultural Exchange》 2002年第5期36-40,共5页
Having taken a night’s rest after our arrival at Likeng Village in Wuyuan County of Jiangxi Province, we were attracted to the riverside at the village entrance by bursts of firecrackers and the sound of gongs and dr... Having taken a night’s rest after our arrival at Likeng Village in Wuyuan County of Jiangxi Province, we were attracted to the riverside at the village entrance by bursts of firecrackers and the sound of gongs and drums. Both banks of the river were crowded with locals and tourists. Many women who had been washing clothes were crowded under a small bridge. They were wielding wooden clubs while talking and laughing loudly. It turned out that this was the day parents 展开更多
关键词 Wedding Ceremony EncounteredThree times a day
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Day Time Sleepiness and Quality of Life Predicts Perceived Stress among Youth
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作者 Sandeep Panchal Monika Yadav 《Journal of Psychological Research》 2021年第2期29-34,共6页
The study examined the predictor of perceived stress among youth.The variables used in the current study were day time sleepiness,quality of life and perceived stress.The sample consists of 150 youth(81Male&69 Fem... The study examined the predictor of perceived stress among youth.The variables used in the current study were day time sleepiness,quality of life and perceived stress.The sample consists of 150 youth(81Male&69 Female)with in the age range of 18-24 years.The Epworth Sleepiness Scale(ESS),World Health Organization Quality of Life(WHO-BRIEF),and Perceived Stress Scale(PSS)were used.The data were interpreted after obtaining the descriptive statistics i.e.Mean and SD,Pearson’s Product Moment correlation and step wise multiple regression analysis.The findings indicated that day time sleepiness and quality of life have a significant positive relation with perceived stress among youth.The step wise regression analysis found day time sleepiness and psychological health related quality of life are the predictors of perceived stress.Both the variable accounts for 39%of total variance in perceived stress among youth. 展开更多
关键词 day time sleepiness Quality of life Perceived stress
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计数式TOD跳频码发生器算法的构造 被引量:14
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作者 张申如 梅文华 王庭昌 《电子与信息学报》 EI CSCD 北大核心 2002年第8期1096-1101,共6页
为同步长周期的跳频码序列,必须使用实时时间TOD。一种新的眼光是将跳频码发生算法看作是对TOD这一特殊“信息”序列的“分组加密“变换。单调递增的计数式TOD是目前常用的TOD序列形式,然而,现有的跳频码发生算法并不适应长周期、单调... 为同步长周期的跳频码序列,必须使用实时时间TOD。一种新的眼光是将跳频码发生算法看作是对TOD这一特殊“信息”序列的“分组加密“变换。单调递增的计数式TOD是目前常用的TOD序列形式,然而,现有的跳频码发生算法并不适应长周期、单调递增计数式TOD的使用,该文讨论了分析、改造跳频码序列发生算法使之适合长周期单调递增计数式TOD的需求、又保持良好跳频特性这一重要任务。 展开更多
关键词 跳频通信 码发生器 实时时间 tod 跳频序列 发生算法
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星火TOD交通枢纽结构设计 被引量:2
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作者 石异 李华峰 +5 位作者 李伟强 束伟农 周钢 王媛 周忠发 崔建华 《建筑结构》 CSCD 北大核心 2021年第19期13-17,71,共6页
星火TOD交通枢纽地下5层、地上2层,包括站厅层、站台层、枢纽大厅等。考虑了地下结构与地上结构与岩土的非线性动力特征,采用了反应位移法对地铁站部位进行抗震设计,并采用了岩土与结构三维动力时程法进行地下结构整体抗震校核设计,更... 星火TOD交通枢纽地下5层、地上2层,包括站厅层、站台层、枢纽大厅等。考虑了地下结构与地上结构与岩土的非线性动力特征,采用了反应位移法对地铁站部位进行抗震设计,并采用了岩土与结构三维动力时程法进行地下结构整体抗震校核设计,更加真实地反映了岩土的动力特性和结构的空间效应。枢纽大厅钢结构采用网格巨柱、斜支撑及周边钢柱支承的单层菱形网格钢网壳体系,采用有限元分析方法、考虑双非线性的极限承载力分析等方法进行设计。结果表明:通过上述设计方法可以保证结构的刚度、承载力、稳定性均满足规范要求。 展开更多
关键词 tod交通枢纽 地下抗震 网格巨柱 岩土与结构三维动力时程法
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Temporal and spatial differences in human activities performed in Urban Green Spaces of Vilnius(Lithuania)
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作者 Luís Valença Pinto Carla Sofia Santos Ferreira Paulo Pereira 《Geography and Sustainability》 CSCD 2024年第2期302-317,共16页
Urban green spaces(UGS)are relevant to city well-being,as recognized by the United Nations’Sustainable Development Goals(SDGs).However,few studies have studied the temporal use of UGS.This work assessed the seasonal,... Urban green spaces(UGS)are relevant to city well-being,as recognized by the United Nations’Sustainable Development Goals(SDGs).However,few studies have studied the temporal use of UGS.This work assessed the seasonal,weekly,and daily use of three urban green spaces(Vingis Park,Bernardino Garden,and Jomantas Park)in Vilnius(Lithuania).The study is based on an on-site observation-based survey,which recorded users’characteristics,activities,and weather conditions during summer and winter.The results showed that UGS’s seasonal,weekly,and daily use differed according to park and users’characteristics.Parks with a higher diversity of facilities had a high seasonal difference in the number of observed activities.User numbers were higher in the summer for activities with children,social activities,sports,and water activities than in the winter.Jomantas Park had the lowest variability in user characteristics.Weather variables were linked to changes in users’activities.Higher precipitation and lower temperature were associated with reducing the number of users and the diversity of registered activities.Most of the stationary activities were observed during summer.The diversity of the observed activities was associated with the available facilities rather than the park size.The distribution of stationary activities was spatially correlated with facility/equipment(benches,playgrounds,sports,and fitness equipment)and proximity to water features.The results of this study are relevant for UGS design,planning,and management. 展开更多
关键词 Urban parks Seasonal differences Temporal use time of day Spatial distribution of UGS users
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基于北斗的高精度时钟设备检测系统
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作者 张丽萍 贺星 +1 位作者 王晓晨 李晨航 《现代导航》 2024年第1期39-44,共6页
描述了一种基于北斗的高精度时钟设备检测系统。该系统利用北斗接收机对内置铷钟进行实时驯服和校正,作为系统时频基准,通过直接数字式频率合成器技术产生各模块所需的时频源,再分别经过信号调制和调理输出所需的最终信号(各种频率信号... 描述了一种基于北斗的高精度时钟设备检测系统。该系统利用北斗接收机对内置铷钟进行实时驯服和校正,作为系统时频基准,通过直接数字式频率合成器技术产生各模块所需的时频源,再分别经过信号调制和调理输出所需的最终信号(各种频率信号和E1信号)。同时,系统对正弦波、方波和三角波波形调理,采用多周期多相位同步方法实现各种频率信号的测量;并通过FPGA实现多种时频信号的测试,包括B码信号、精密时间协议(PTP)信号、网络时间协议(NTP)信号和秒脉冲+对天时间(1PPS+TOD)信号。 展开更多
关键词 北斗 B码 PTP NTP 1PPS+tod 时频信号
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基于时间信息(TOD)的跳频通信系统仿真 被引量:2
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作者 王壮 余国文 《舰船电子工程》 2012年第9期95-97,共3页
介绍了一种基于时间信息TOD的跳频通信系统,重点分析了时间信息TOD的格式设计和作用,描述了TOD的产生原理,建立了包含TOD同步系统的跳频通信模型,设定仿真条件,在Simulink工具中,得到了预期的仿真结果。仿真结果验证了该系统的可行性,... 介绍了一种基于时间信息TOD的跳频通信系统,重点分析了时间信息TOD的格式设计和作用,描述了TOD的产生原理,建立了包含TOD同步系统的跳频通信模型,设定仿真条件,在Simulink工具中,得到了预期的仿真结果。仿真结果验证了该系统的可行性,为下一步研究对跳频通信系统的干扰提供依据。 展开更多
关键词 时间信息 跳频系统 同步字头 时频分析 SIMULINK
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基于熵值法的高速铁路TOD项目开发时机成熟度评价研究 被引量:2
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作者 徐艳琴 《铁道运输与经济》 北大核心 2022年第12期104-111,共8页
高速铁路TOD项目开发未达预期,在项目投资机会筛选阶段,开发时机成熟度评价至关重要。针对高速铁路站点周边土地价值影响因素,确定TOD项目开发时机成熟度评价指标体系,基于熵值法构建评价模型,并通过实例验证模型适用性。实证结果表明:... 高速铁路TOD项目开发未达预期,在项目投资机会筛选阶段,开发时机成熟度评价至关重要。针对高速铁路站点周边土地价值影响因素,确定TOD项目开发时机成熟度评价指标体系,基于熵值法构建评价模型,并通过实例验证模型适用性。实证结果表明:城市发展因素、个别因素及交通因素是影响高速铁路TOD项目开发时机成熟度的三大关键因素;交通因素对不同级别城市高速铁路TOD项目影响路径不同,对外交通便利度是影响中小城市TOD项目开发时机成熟度的重要因子,对内交通便利度对大城市影响更显著;基于熵值法构建的评价模型适用于高速铁路、城际轨道交通、快速轨道交通站点TOD项目比选,在应用条件及应用范围上存在优势。 展开更多
关键词 高速铁路 tod 熵值法 指标体系 开发时机成熟度
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轨道交通TOD地区的步行尺度 被引量:34
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作者 刘泉 《城市规划》 CSSCI CSCD 北大核心 2019年第3期88-95,共8页
轨道交通TOD站点地区确定规划圈层边界的重要依据之一是步行尺度,即步行距离形成的半径,但不同城市的TOD地区步行尺度并不相同。步行距离虽然能指导划定圈层边界和影响范围,但对步行决策起主导作用的则是步行时间,二者按照"时间-距... 轨道交通TOD站点地区确定规划圈层边界的重要依据之一是步行尺度,即步行距离形成的半径,但不同城市的TOD地区步行尺度并不相同。步行距离虽然能指导划定圈层边界和影响范围,但对步行决策起主导作用的则是步行时间,二者按照"时间-距离"换算关系相互关联,并受到地形条件、空间布局、交通环境等步行环境要素的制约。TOD地区步行尺度的差异是由于步行时间、步行距离和步行环境差异所造成的。对TOD地区步行尺度的差异及原因进行总结,可以为我国TOD地区规划确定合理的步行尺度及TOD模型提供有益的借鉴思路。 展开更多
关键词 T0D 步行尺度 步行距离 步行时间 步行环境
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Trend and Periodicity of Temperature Time Series in Ontario 被引量:1
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作者 Syed Imran Ahmed Ramesh Rudra +1 位作者 Trevor Dickinson Motahir Ahmed 《American Journal of Climate Change》 2014年第3期272-288,共17页
The trends and periodicities in the annual and seasonal temperature time series at fifteen weather stations within Ontario Great Lakes Basins have been analyzed, for the period 1941-2005, using the statistical analyse... The trends and periodicities in the annual and seasonal temperature time series at fifteen weather stations within Ontario Great Lakes Basins have been analyzed, for the period 1941-2005, using the statistical analyses (Fourier series analysis, t-test, and Mann-Kendall test). The stations were spatially divided into three regions: northwest (NW), southwest (SW), and southeast (SE) to evaluate spatial variability in temperature. The results of the study reveal that the annual maximum mean temperature showed increasing trend for NW, and mixed trends for SW and SE regions. The variability was found to be more for northern stations as compared to southern stations for annual extreme minimum temperature. In addition, the trend slope per 100 years for the average annual extreme minimum temperature increased within the range of -0.8°C (Stratford) to 15°C (Porcupine). The seasonal analysis demonstrated that extreme maximum temperature has an increasing trend and maximum mean temperature has a decreasing trend during summer and winter. The extreme minimum temperature for winter illustrated an increasing trend (90%) with 22% statistically significant for NW region. For the SW region, the trend is also increasing (80%) for most of the temperature variables and 25% of temperature data were significantly increased in the SW region. The SE region stations showed overall very clear increasing trends (95%) for all the temperature variables. The data also showed that 47% of data were statistically significant in the SE region. The analysis of variance accounted for by trend, significant periodicities, and random component show that the pattern is similar for the percent of variance accounted for periodicities, and random component contribute dominantly for the four temperature variables and frost free days (FFD) for all three regions. Overall, the study reveals that the extreme minimum temperature is increasing annually and seasonally, with statistically significant at many stations. 展开更多
关键词 time Series TREND PERIODICITY MANN-KENDALL Test T-TEST FROST Free days
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TOD-伪码同步辅助快跳频同步方法 被引量:2
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作者 欧春湘 吴智杰 《现代防御技术》 2018年第2期93-98,共6页
在FH扩频系统中,只有收发双方的跳频频率在时间上同步才能够解调出准确的数据信息。针对直跳扩(DS/FH)体制的通信系统存在跳频同步困难的问题,提出了一种基于TOD同步法的TOD-伪码同步辅助快跳频同步方法。本方法利用伪码同步结果对跳频... 在FH扩频系统中,只有收发双方的跳频频率在时间上同步才能够解调出准确的数据信息。针对直跳扩(DS/FH)体制的通信系统存在跳频同步困难的问题,提出了一种基于TOD同步法的TOD-伪码同步辅助快跳频同步方法。本方法利用伪码同步结果对跳频时间差进行补偿,进一步消除TOD时间带来的误差以实现精确跳频同步,提高跳频时间误差估计精度。通过仿真结果可知,伪码同步辅助跳频同步后进一步降低了跳频时间误差,且随着信噪比的增加残留的跳频时间误差越小。本方法不仅解决了长码带来的存储问题还实现了快速同步,且能够达到很高的同步精度,因此具有很强的抗干扰性。 展开更多
关键词 跳频 同步 tod 伪码同步 抗干扰 长码
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Effects of Sowing Time on the Seed Yield of Quinoa (Chenopodium quinoa Willd) in South Kanto, Japan
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作者 Katsunori Isobe Hikaru Sugiyama +6 位作者 Daisuke Okuda Yudai Murase Hiroki Harada Misa Miyamoto Syunsuke Koide Masao Higo Yoichi Torigoe 《Agricultural Sciences》 2016年第3期146-153,共8页
The objective of the present study was to determine the optimum sowing time of three quinoa ecotypes (Altipllano, sea level, and valley) for high seed yields in south Kanto, Japan. Pot experiments were conducted in th... The objective of the present study was to determine the optimum sowing time of three quinoa ecotypes (Altipllano, sea level, and valley) for high seed yields in south Kanto, Japan. Pot experiments were conducted in the experimental field at Nihon University during 2011, 2012, 2013, and 2014. In this experiment, the following quinoa varieties were used NL-6, Baer Cajon and Cauquenes (sea-level type), Amarilla de Marangani, Blanca de Junin, CICA-127, ECU-420, ECU-525, Ingapirica, and Narino (valley type), 94R and Isluga (Altiplano type). The quinoa seeds were sown on March 29, June 17 and September 22, 2011;March 27, June 17 and August 28, 2012;March 26, June 15 and 5 September 5, 2013;and March 27, June 17 and August 28, 2014. When the sea-level type and Altiplano type seeds were sowed from March to September, the seeds could be gained in all sowing plots. However, the seed weights of all varieties were the highest in the sowing plots of March. And the seed weights in the sowing plot of March were significantly higher than that in the other sowing plots. The sea-level type and Altiplano type quinoa had almost the same seed growth reaction for day length and day temperature. Thus, to gain a high seed yield of the sea-level and Altiplano type quinoa, March was the optimum sowing time in south Kanto, Japan. When the valley-type seeds were sowed from March to June, the seeds could not be gained, except in 2012. In 2012, the seed weights and seed numbers in sowing plots of March and June were significantly lower than those in the sowing plot of September. Thus, to obtain a high seed yield of the valley type quinoa, the optimum sowing time in south Kanto, Japan was from August to September. 展开更多
关键词 day Length day Temperature ECOTYPE Sowing time QUINOA
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构建以人为本全民全面共享可持续发展的TOD全时综合体——苏州龙湖东吴天街规划设计实践
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作者 黄昕达 《城市建筑》 2022年第8期188-192,共5页
一个城市中心级别的综合体是多个建筑和多种功能有机高效的结合。构建以人为本、全民共享、全面共享的可持续发展的TOD全时综合体,符合人类对城市健康持久发展的要求。苏州龙湖东吴天街通过在中庭布局“飞天梯”分流乘地铁到达的顾客在... 一个城市中心级别的综合体是多个建筑和多种功能有机高效的结合。构建以人为本、全民共享、全面共享的可持续发展的TOD全时综合体,符合人类对城市健康持久发展的要求。苏州龙湖东吴天街通过在中庭布局“飞天梯”分流乘地铁到达的顾客在其中的分布情况,提高了顾客出行的时间效率。本文借鉴苏州园林设计手法构建具有历史的层积感中庭空间,传承了地域文化;通过对不同顾客需求空间的分类研究合理布局,为顾客提供分隔、分层、分时、分化共享的空间;立足于资源、文化、空间共享的原则,建设以人为本、全民共享、全面共享的东吴天街,使其成长为可持续发展的TOD全时综合体。 展开更多
关键词 tod全时综合体 可持续发展 全民共享 地铁上盖24 h+1模式 动态更新 历史的层积
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Thermal and photoperiodic requirements of the seedling stage of three tropical forest species
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作者 Fabrina Bolzan Martins Mábele de Cássia Ferreira +1 位作者 Flávia Fernanda Azevedo Fagundes Gabriel Wilson Lorena Florêncio 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第1期209-220,共12页
Air temperature and photoperiod play an important role in the seedling development for tropical forest species.Both variables are sensitive to climate,and so evaluating thermal and photoperiodic effects on seedling de... Air temperature and photoperiod play an important role in the seedling development for tropical forest species.Both variables are sensitive to climate,and so evaluating thermal and photoperiodic effects on seedling development is fundamental,especially for climate change studies.Methods to quantify thermal time and the energy required for plants to reach a development stage include air temperature and cardinal temperatures.The photoperiod will also affect physiological reactions of a plant and thus its development.Here we evaluated the six thermal time methods widely used to compute thermal requirement,and identified the influence of the photoperiod from the 2015 and2016 growing seasons and 12 sowing dates in Itajubá,Minas Gerais state,Brazil,on seedling development of three native tropical forest species Psidium guajava L.(Myrtaceae),Citharexylum myrianthum Cham.(Verbenaceae),and Bixa orellana L.(Bixaceae).The method used to quantify thermal time influenced the analytical results of seedling development;the one that considered three cardinal temperatures and compared them with the mean air temperature(Method5)performed better in computing thermal requirements.The influence of photoperiod on seedling development was inconclusive for the three species,but all three developed better in mild temperatures(between 13.3℃and 26.9℃)with a photoperiod shorter than 13 h. 展开更多
关键词 PHYLLOCHRON Thermal time day length Seedling stage PHENOLOGY
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基于有序样本聚类的交叉口交通信号控制算法研究 被引量:9
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作者 宫晓燕 陈德望 刘小明 《公路交通科技》 CAS CSCD 北大核心 2003年第1期101-104,共4页
针对现有多时段TOD算法和感应控制算法存在的弊端 ,从实用角度出发 ,提出一种将基于有序样本聚类的多时段TOD算法和感应控制算法相结合的交叉口交通信号控制算法。它把路口流量与路口饱和流量的比值Y作为选择感应控制算法和多时段TOD算... 针对现有多时段TOD算法和感应控制算法存在的弊端 ,从实用角度出发 ,提出一种将基于有序样本聚类的多时段TOD算法和感应控制算法相结合的交叉口交通信号控制算法。它把路口流量与路口饱和流量的比值Y作为选择感应控制算法和多时段TOD算法的评价参数 ,当Y大于 80 %时 ,采用基于有序样本聚类的多时段TOD算法 ,当Y小于80 %时 ,采用感应控制算法。本文采用Corsim5 0分别对四相位、三相位、两相位的路口进行仿真 ,结果表明本文所提算法在充分利用现有资源的前提下 ,不仅改进了现有控制算法的控制效果 ,而且计算简单 。 展开更多
关键词 有序样本聚类 交叉口 交通信号控制算法 感应控制算法 时段划分 tod算法
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基于混合聚类的城市道路多时段控制研究 被引量:5
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作者 姚佼 徐洁琼 《计算机应用研究》 CSCD 北大核心 2016年第11期3274-3278,共5页
多方案控制具有简单实用、可靠性好、稳定性高、性价比高等优点,在城市交通控制中得到了广泛应用。在利用指数平滑异同移动平均法对缺失交通数据进行修补的基础上,运用快速聚类与系统聚类相结合的混合聚类方法对交通数据进行分析,并以... 多方案控制具有简单实用、可靠性好、稳定性高、性价比高等优点,在城市交通控制中得到了广泛应用。在利用指数平滑异同移动平均法对缺失交通数据进行修补的基础上,运用快速聚类与系统聚类相结合的混合聚类方法对交通数据进行分析,并以经典的Silhouttte评价指标作为聚类终止条件,同时兼顾/考虑了交通数据时序性,消除聚类结果中的三类奇异点,最后利用交通信号配时软件SYNCHRO制定了相应时段的控制方案。相关的案例分析显示,优化后的多时段控制方案可以更好地适应交通流的波动,车均延误减少9.79%,其中时序性考虑可以有效改善控制方案频繁切换对交通流的扰动,避免其负效应对混合聚类改善效果的影响。 展开更多
关键词 混合聚类 多时段 交通控制 Silhouttte指标 时序性
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轨道交通影响下的大都市空间尺度 被引量:10
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作者 张育南 《都市快轨交通》 2007年第3期12-16,共5页
基于一小时通勤时间控制,分析轨道交通与步行系统结合对城市规划的作用,探讨符合TOD(轨道交通引导城市发展)模式的混合开发和高密度土地利用;从绿色城市的角度,分析大都市尺度下的城市开发、土地利用与轨道建设之间的规律。
关键词 一小时通勤时间 步行尺度 城市轨道交通tod 混合开发
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