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Water Usage Patterns and Water Saving Devices in Households: A Case of Eastleigh, Nairobi 认领
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作者 Muhammad Ali Geryyshom Munala +3 位作者 Teckla Muhoro James Shikuku Victor Nyakundi Andrew Gremley 《水资源与保护(英文)》 2020年第4期303-315,共13页
Water conservation measures are rapidly becoming a necessity in urban environments all over Africa and the world. There is little innovation and available information for homeowners, building professionals and practit... Water conservation measures are rapidly becoming a necessity in urban environments all over Africa and the world. There is little innovation and available information for homeowners, building professionals and practitioners to guide towards water conservation. Water scarcity has progressively increased over periods of time in Eastleigh due to increased population density from increased high-rise apartments. The study tries to establish how water usage patterns and water conservation devices can potentially reduce water consumption levels. In the study area, 96% of the families are faced with problems related to water supply and hence are forced to come up with water conservation and adaptation strategies due to the scarcity of water. The study used survey and descriptive research design, and collected data on water usage patterns and water conservation devices from a total of 230 households in Biafra and Sewage estates in the Eastleigh neighbourhood. The results indicated that 76% of the households did not have water saving devices while the other 24% had water saving devices such as the dual flush toilets, low flow high-efficiency faucet aerators, low flow plumbing fixtures and automatic shut-off nozzles. A unit increase in water saving devices will lead to a 0.512 decrease in water consumption level. The study recommends that low-income households use water saving devices and develop water management strategies such as water-saving plumbing fixtures, rainwater harvesting, and grey water reuse. 展开更多
关键词 WATER SAVING DEVICES WATER USAGE PATTERNS NAIROBI
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Experimental Investigation of Laser Surface Hardening of AISI 4340 Steel Using Different Laser Scanning Patterns 认领
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作者 Baha Tarchoun Abderrazak El Ouafi Ahmed Chebak 《矿物质和材料特性和工程(英文)》 2020年第2期9-26,共18页
Laser surface transformation hardening becomes one of the most modern processes used to improve fatigue and wear properties of steel surfaces. In this process, the material properties and the heating parameters are th... Laser surface transformation hardening becomes one of the most modern processes used to improve fatigue and wear properties of steel surfaces. In this process, the material properties and the heating parameters are the factors that present the most significant effects on the hardened surface attributes. The control of these factors using predictive modeling approaches to achieve desired surface properties leads to conclusive results. However, when the dimensions of the surface to be treated are larger than the cross-section of the laser beam, various laser-scanning patterns are involved. This paper presents an experimental investigation of laser surface hardening of AISI 4340 steel using different laser scanning patterns. This investigation is based on a structured experimental design using the Taguchi method and improved statistical analysis tools. Experiments are carried out using a 3 kW Nd: YAG laser source in order to evaluate the effects of the heating parameters and patterns design parameters on the physical and geometrical characteristics of the hardened surface. Laser power, scanning speed and scanning patterns (linear, sinusoidal, triangular and trochoid) are the factors used to evaluate the hardened depth and the hardened width variations and to identify the possible relationship between these factors and the hardened zone attributes. Various statistical tools such as ANOVA, correlations analysis and response surfaces are applied in order to examine the effects of the experimental factors on the hardened surface characteristics. The results reveal that the scanning patterns do not modify the nature of the laser parameters’ effects on the hardened depth and the hardened width. But they can accentuate or reduce these effects depending on the type of the considered pattern. The results show also that the sinusoidal and the triangular patterns are relevant when a maximum hardened width with an acceptable hardened depth is desired. 展开更多
关键词 LASER Surface HARDENING Process Experimental Investigation LASER Scanning PATTERNS AISI 4340 STEEL Hardness Profile Hardened Depth Hardened WIDTH Design of Experiment Analysis of Variance
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从对地观测到对人观测——浅析社会地理计算 认领
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作者 李德仁 呙维 +1 位作者 常晓猛 李熙 《地理学报:英文版》 SCIE CSCD 2020年第2期233-250,共18页
It is possible to obtain vast amounts of spatiotemporal data related to human activities to support the study of human behavior and social evolution.In this context,geography,with the human-nature relationship as its ... It is possible to obtain vast amounts of spatiotemporal data related to human activities to support the study of human behavior and social evolution.In this context,geography,with the human-nature relationship as its core,is undergoing a transition from strictly earth observations to the observation of human activities.Geocomputation for social science is one manifestation thereof.Geocomputation for social science is an interdisciplinary approach combining remote sensing techniques,social science,and big data computation.Driven by the availability of spatially and temporally expansive big data,geocomputation for social science uses spatiotemporal statistical analyses to detect and analyze the interactions between human behavior,the natural environment,and social activities;Remote sensing(RS)observations are used as primary data.Geocomputation for social science can be used to investigate major social issues and to assess the impact of major natural and societal events,and will surely be an area of focused development in geography in the near future.We briefly review the background of geocomputation in the social sciences,discuss its definition and disciplinary characteristics,and highlight the main research foci.Several key technologies and applications are also illustrated with relevant case studies of the Syrian Civil War,typhoon transits,and traffic patterns. 展开更多
关键词 GEOCOMPUTATION for SOCIAL science NIGHTTIME light remote sensing SOCIAL network TRAFFIC patterns
Thermal Diagnosis of Heat Conduction and Combustion Time of Fruits of the Brazil Nut Tree (<i>Bertholletia excelsa</i>Bonpl.) 认领
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作者 Adenes Teixeira Alves Lucieta Guerreiro Martorano +4 位作者 Gelson Dias Florentino Dimas José Lasmar íres Paula de Andrade Miranda Leila Sheila Lisboa Jamal da Silva Chaar 《生命科学与技术进展(英文)》 2020年第2期60-71,共12页
The objective of this work was to evaluate the spatial and temporal dynamics of the process of combustion of fruits of the Brazil nut tree (Bertholletia excelsa Bonpl.) using thermographic images in order to character... The objective of this work was to evaluate the spatial and temporal dynamics of the process of combustion of fruits of the Brazil nut tree (Bertholletia excelsa Bonpl.) using thermographic images in order to characterize the potential of this biomass as an energy source for use in ceramic kilns. Infrared thermography was used as a diagnostic tool, and the trial was conducted in November 2018, in two blocks with two repetitions in each, with the fruits organized so that the cavity was oriented upward and also downward. The thermograms were analyzed using Flir Tools (6.3 v). The temperatures were the highest in the center of the fruits (>160&deg;C), attaining incandescence in 6 min 30 s. Heat was propagated from the center to the edge, and this process was quicker for fruits with their cavities pointed upward. A second order polynomial model explained combustion time with a maximum duration of 7.2 minutes. The thermographic diagnostic has the potential to be used in management strategies for this biomass as an energy source, thus aggregating value to the residuals that are normally left in the forest during harvest by extractivists. 展开更多
关键词 RESIDUAL Biomass Thermographic Patterns NON-WOOD FOREST Products
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Dietary Patterns and Empirical Dietary Inflammatory Index in Southern Brazil and Risk of Colorectal Cancer: A Case-Control Study 认领
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作者 Raquel Goreti Eckert-Dreher Daniela Coelho dos Santos +3 位作者 André Wust Zibetti Karina Bettega Felipe Danilo Wilhelm-Filho Rozangela Curi Pedrosa 《食品与营养科学(英文)》 2020年第4期281-300,共20页
Background and Aims: To evaluate the dietary habits of individuals with colorectal cancer (CRC) and healthy adults living in southern Brazil. Methods: The anthropometric assessment was carried out according to the WHO... Background and Aims: To evaluate the dietary habits of individuals with colorectal cancer (CRC) and healthy adults living in southern Brazil. Methods: The anthropometric assessment was carried out according to the WHO standard and eating habits were assessed using a questionnaire food frequency. The dietary inflammatory index (eDII) was calculated based on the frequency of consumption of anti- and pro-inflammatory foods. Results: 178 colorectal cancer cases and 178 controls were included, age over 50 years (81.7%). 38.2% of CRC individuals were smokers or former smokers and 69.1% were overweight, 15.7% had type II diabetes and 41% had hypertension. The consumption of bread and white rice (OR 1365.8;p < 0.001), meat processed up to twice a week (OR 227.35;p = 0.001) and low fruit intake (OR 40.569;p = 0.039) increased the risk for CRC development. The eDII greater than 0 and 3 increases the risk of CRC for women (OR 55.83;95% CI 6.53 - 477.16;p < 0.001) and men (OR 66.75;95% CI 19.05 - 233;p Conclusions: In the south of Brazil, the Western diet pattern was related to the diagnosis of CRC, in addition to the male gender, smoking and overweight. In an unprecedented way for the Brazilian population, we associate eDII with the risk of CRC. 展开更多
关键词 Colorectal Cancer DIETARY INFLAMMATORY INDEX DIETARY Patterns SMOKERS OVERWEIGHT
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文章速递稳定性冠心病合并脂代谢异常的中医证候分布特征 认领
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作者 方格 任琦 +2 位作者 王彬 周小文 李先涛 《北京中医药大学学报》 CAS CSCD 北大核心 2020年第5期427-431,共5页
目的探讨稳定性冠心病合并脂代谢异常的中医证候分布特征。方法通过临床流行病学调查,采用多元统计方法,分析稳定性冠心病合并脂代谢异常的症状频次,对中医证候分布特征进行主成分分析、因子分析、聚类分析。结果稳定性冠心病合并脂代... 目的探讨稳定性冠心病合并脂代谢异常的中医证候分布特征。方法通过临床流行病学调查,采用多元统计方法,分析稳定性冠心病合并脂代谢异常的症状频次,对中医证候分布特征进行主成分分析、因子分析、聚类分析。结果稳定性冠心病合并脂代谢异常患者的证候主成分分析,取特征值大于1的主成分,其累计贡献率为61.81%;因子分析共提取了10个公因子,对10个公因子进行聚类分析,聚为4类特征群。结论稳定性冠心病合并脂代谢异常的中医证候分布归为4类证候群,多为本虚标实、虚实夹杂之证,本虚有阴虚及气阴两虚,标实有血瘀、痰湿,主要涉及心、脾、肾3脏,研究为提高中医辨证论治水平和临床疗效提供了参考依据。 展开更多
关键词 冠心病 脂代谢异常 证候 分布
文章速递高职院校与园区企业的合作模式探讨 认领
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作者 王慧华 《科技广场》 2020年第2期40-47,共8页
职业教育具有跨界性,这就决定了其在办学过程中要走校企合作的模式。当前高职院校方虽然意识到校企合作的重要性,也在积极探索合作方式,但是由于各种原因,在合作模式与合作深度上有明显不足。园区企业由于掌握了用人的主动权,而且短期... 职业教育具有跨界性,这就决定了其在办学过程中要走校企合作的模式。当前高职院校方虽然意识到校企合作的重要性,也在积极探索合作方式,但是由于各种原因,在合作模式与合作深度上有明显不足。园区企业由于掌握了用人的主动权,而且短期内看不到合作产生的经济效益,所以在合作上也不是很积极。双方存在的各种问题自然也就导致合作效果欠佳。本文通过对双方合作方式进行探讨,分析了当前几种比较典型的合作模式,最后得出结论。建议当地政府能够出面成立相关职能部门专门管理校企合作,使合作能取得实际意义,实现真正的资源优化配置。 展开更多
关键词 校企合作 人才培养 模式
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Identifying spatiotemporal traffic patterns in large-scale urban road networks using a modified nonnegative matrix factorization algorithm 认领
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作者 Xiaolei Ma Yi Li Peng Chen 《交通运输工程学报:英文版》 CSCD 2020年第4期529-539,共11页
The identification and analysis of spatiotemporal traffic patterns in road networks constitute a crucial process for sophisticated traffic management and control.Traditional methods based on mathematical equations and... The identification and analysis of spatiotemporal traffic patterns in road networks constitute a crucial process for sophisticated traffic management and control.Traditional methods based on mathematical equations and statistical models can hardly be applicable to large-scale urban road networks,where traffic states exhibit high degrees of dynamics and complexity.Recently,advances in data collection and processing have provided new opportunities to effectively understand spatiotemporal traffic patterns in large-scale road networks using data-driven methods.However,limited efforts have been exerted to explore the essential structure of the networks when conducting a spatiotemporal analysis of traffic characteristics.To this end,this study proposes a modified nonnegative matrix factorization algorithm that processes high-dimensional traffic data and provides an improved representation of the global traffic state.After matrix factorization,cluster analysis is conducted based on the obtained low-dimensional representative matrices,which contain different traffic patterns and serve as the basis for exploring the temporal dynamics and spatial structure of network congestion.The applicability and effectiveness of the proposed approach are examined in a road network of Beijing,China.Results show that the methods exhibit considerable potential for identifying and interpreting the spatiotemporal traffic patterns over the entire network and provide a systematic and efficient approach for analyzing the network-level traffic state. 展开更多
关键词 Large-scale network Traffic state Spatiotemporal patterns Nonnegative matrix factorization
馆藏清代官服的科学分析及其服饰工艺 认领
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作者 赵作勇 《服装学报》 CAS 2020年第2期126-133,共8页
以中国国家博物馆一件清代织锦缠枝牡丹吉祥纹土司官服为研究对象,采用显微观察、便携式能谱、红外光谱等方法对文物的保存状况进行分析检测,科学评估文物存在的各种病害,同时研究文物的形制结构、裁剪方法、所用布料的组织结构、缝合... 以中国国家博物馆一件清代织锦缠枝牡丹吉祥纹土司官服为研究对象,采用显微观察、便携式能谱、红外光谱等方法对文物的保存状况进行分析检测,科学评估文物存在的各种病害,同时研究文物的形制结构、裁剪方法、所用布料的组织结构、缝合方式和纹样等。研究结果为该文物的储存、展示和进一步保护修复工作提供准确的基础信息,也为研究清代纺织品原料品种、生产工艺、服饰制度等提供一定的参考。 展开更多
关键词 清代官服 材质 工艺 纹样 科学分析
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Collapse Patterns and Their Discrimination of Reinforced Concrete Shear Wall Under Combined Stresses of Compression and Shear due to Strong Earthquake 认领
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作者 查支祥 刘西拉 许波 《上海交通大学学报:英文版》 EI 2020年第4期495-508,共14页
The collapse patterns of reinforced concrete(RC)shear walls under seismic load are proposed.The crack distribution and propagation of shear walls are specifically based on the failure criterions of Mohr-Coulomb with t... The collapse patterns of reinforced concrete(RC)shear walls under seismic load are proposed.The crack distribution and propagation of shear walls are specifically based on the failure criterions of Mohr-Coulomb with tension cutoff.Three zones and five different corresponding failure modes of RC shear walls are determined according to the transfer path of shear stress in shear wall.These failure modes of shear walls under seismic load are verified by many experimental results and can be utilized in collapsing analysis for frame-shear wall structure. 展开更多
关键词 reinforced concrete(RC) shear walls collapsing patterns seismic load
Compressed ghost imaging based on differential speckle patterns 认领
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作者 王乐 赵生妹 《中国物理B:英文版》 SCIE EI CAS CSCD 2020年第2期294-300,共7页
We propose a compressed ghost imaging scheme based on differential speckle patterns,named CGI-DSP.In the scheme,a series of bucket detector signals are acquired when a series of random speckle patterns are employed to... We propose a compressed ghost imaging scheme based on differential speckle patterns,named CGI-DSP.In the scheme,a series of bucket detector signals are acquired when a series of random speckle patterns are employed to illuminate an unknown object.Then the differential speckle patterns(differential bucket detector signals)are obtained by taking the difference between present random speckle patterns(present bucket detector signals)and previous random speckle patterns(previous bucket detector signals).Finally,the image of object can be obtained directly by performing the compressed sensing algorithm on the differential speckle patterns and differential bucket detector signals.The experimental and simulated results reveal that CGI-DSP can improve the imaging quality and reduce the number of measurements comparing with the traditional compressed ghost imaging schemes because our scheme can remove the environmental illuminations efficiently. 展开更多
关键词 GHOST imaging compressed sensing DIFFERENTIAL SPECKLE patterns DIFFERENTIAL BUCKET DETECTOR SIGNALS
Analysis of Design Rainstorm Hydrograph Based on Asymmetrical Extreme Value Copula 认领
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作者 Zishen CHEN Lingling ZHAO Xing YANG 《气象与环境研究:英文版》 CAS 2020年第3期38-43,共6页
In this paper,the maximum 1-hour rainfall( rain peak),the maximum 6-hour rainfall and the maximum 24-hour rainfall in the Caojiang River basin from 1967 to 2013 were taken as samples. The typical typhoon rainstorm hyd... In this paper,the maximum 1-hour rainfall( rain peak),the maximum 6-hour rainfall and the maximum 24-hour rainfall in the Caojiang River basin from 1967 to 2013 were taken as samples. The typical typhoon rainstorm hydrograph of joint distribution of rainfall in three periods was constructed based on the asymmetric Archimedean Gumbel-Hougaard extreme value Copula. The main conclusions were as follows:( 1) the design rainstorm value in the Caojiang River basin calculated by using the joint distribution of rainfall in three periods was larger than the design rainstorm value of the joint distribution in two periods and that of a single period. The design rainstorm process hydrograph amplified at the same frequency had the optimal overall effect,which provided a new idea and method for studying the design rainfall patterns.( 2) According to the maximum 24-hour rainfall,the risk rate of the multi-peak rainstorm process that the main peak was in the back was the highest,and the constructed typical design rainstorm process hydrograph was the most representative.( 3) " OR" joint return period of rainfall combination in three periods as the design criteria of a watershed was applicable to responding to the risk of rainfall and flood in this watershed. 展开更多
关键词 Asymmetrical extreme value Copula Design rainstorm hydrograph "OR"return period Rainfall patterns
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浅析海报设计中图与底的创意表现 认领
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作者 金彩月 曹智聪 +2 位作者 苗昊天 吴爽 齐飞 《科教文汇》 2020年第4期86-88,共3页
海报的构成要素主要是以点、线、面、色、形和纹理等基本元素组成,这些元素在我们的物理形式中都是可以感知的。依据设计者的意图,运用点、线、面、色、形和纹理在二维平面中建立空间关系,形成了让读者直观感受到的海报形式。在构成形... 海报的构成要素主要是以点、线、面、色、形和纹理等基本元素组成,这些元素在我们的物理形式中都是可以感知的。依据设计者的意图,运用点、线、面、色、形和纹理在二维平面中建立空间关系,形成了让读者直观感受到的海报形式。在构成形式的转换中,当正负形被提升时,作品的设计意象会变得更具吸引力,使幻象与现实之间转换产生为视觉的心理反应,使海报主题的视觉感受更加直观且具有冲击力。通过正负形构成和意象形式的应用,在海报设计领域具有广泛的应用价值。 展开更多
关键词 海报设计 图形 色彩 创意
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Impacts of ontogenetic and altitudinal changes on morphological traits and biomass allocation patterns of Fritillaria unibracteata 认领
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作者 XU Bo WANG Jin-niu SHI Fu-sun 《山地科学学报:英文版》 SCIE CSCD 2020年第1期83-94,共12页
Environmental variations and ontogeny may affect plant morphological traits and biomass allocation patterns that are related to the adjustments of plant ecological strategies. We selected 2-, 3-and 4-year-old Fritilla... Environmental variations and ontogeny may affect plant morphological traits and biomass allocation patterns that are related to the adjustments of plant ecological strategies. We selected 2-, 3-and 4-year-old Fritillaria unibracteata plants to explore the ontogenetic and altitudinal changes that impact their morphological traits(i.e., plant height, single leaf area,and specific leaf area) and biomass allocations [i.e.,biomass allocations of roots, bulbs, leaves, stems, and flowers] at relatively low altitudinal ranges(3400 m to 3600 m asl) and high altitudinal ranges(3600 m to4000 m asl). Our results indicated that plant height,root biomass allocation, and stem biomass allocation significantly increased during the process of individual growth and development, but single leaf area, specific leaf area, bulb biomass allocation, and leaf biomass allocation showed opposite trends.Furthermore, the impacts of altitudinal changes on morphological traits and biomass allocations had no significant differences at low altitude, except for single leaf area of 2-year-old plants. At high altitude,significantly reduced plant height, single leaf area and leaf biomass allocation for the 2-year-old plants,specific leaf area for the 2-and 4-year-old plants, and stem biomass allocation were found along altitudinal gradients. Significantly increased sexual reproductive allocation and relatively stable single leaf area and leaf biomass allocation were also observed for the 3-and 4-year-old plants. In addition, stable specific leaf area for the 3-year-old plants and root biomass allocation were recorded. These results suggested that the adaptive adjustments of alpine plants, in particular F. unibracteata were simultaneously influenced by altitudinal gradients and ontogeny. 展开更多
关键词 ALPINE plants MORPHOLOGICAL TRAITS Biomass allocation PATTERNS ONTOGENETIC DRIFTS Altitudinal gradients
Meteorological mechanism for a large-scale persistent severe ozone pollution event over eastern China in 2017 认领
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作者 Jia Mao Lili Wang +6 位作者 Chuhan Lu Jingda Liu Mingge Li Guiqian Tang Dongsheng Ji Nan Zhang Yuesi Wang 《环境科学学报:英文版》 SCIE EI CAS CSCD 2020年第6期187-199,共13页
An intensive and persistent regional ozone pollution event occurred over eastern China from 25 June to 5 July 2017.73 out of 96 selected cities,most located in the Beijing-TianjinHebei and the surrounding area(BTHS),s... An intensive and persistent regional ozone pollution event occurred over eastern China from 25 June to 5 July 2017.73 out of 96 selected cities,most located in the Beijing-TianjinHebei and the surrounding area(BTHS),suffered severe ozone pollution.A north-south contrast ozone distribution,with higher ozone(199±33μg/m3)in the BTHS and lower ozone(118±25μg/m^3)in the Yangtze River Delta(YRD),was found to be dominated by the position of the West Pacific Subtropical High(WPSH)and mid-high latitude wave activities.In the BTHS,the positive anomalies of geopotential height at 500 hPa and temperature at the surface indicated favorable meteorological conditions for local ozone formation.Prevailing northwesterly winds in the mid-high troposphere and warm advection induced by weak southerly winds in the low troposphere resulted in low-moderate relative humidity(RH),less total cloud cover(TGC),strong solar radiation and high temperatures.Moreover,southerly winds prevailing over the BTHS aggravated the pollution due to regional transportation of O3 and its precursors.On one hand,the deep sinking motion and inversion layer suppressed the dispersion of pollutants.On the other hand,O3-rich air in the upper layer was maintained at night due to temperature inversion,which facilitated O3 vertical transport to the surface in the next-day morning due to elevated convection.Generally,temperature,UV radiation,and RH showed good correlations with O3 in the BTHS,with rates of 8.51(μg/m^3)/℃(within the temperature range of 20-38℃),59.54(μg/m^3)/(MJ/m^2)and-1.93(μg/m^3)/%,respectively. 展开更多
关键词 Surface ozone Beijing-Tianjin-Hebei and surrounding area Synoptic patterns Western Pacific subtropical high Meteorological conditions Inversion layer
Information theory of metasurfaces 认领
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作者 Haotian Wu Guo Dong Bai +4 位作者 Shuo Liu Lianlin Li Xiang Wan Qiang Cheng Tie Jun Cui 《国家科学评论:英文版》 SCIE EI CSCD 2020年第3期561-571,共11页
We propose a theory to characterize the information and information processing abilities of metasurfaces,and demonstrate the relation between the information of the metasurface and its radiation pattern in the far-fie... We propose a theory to characterize the information and information processing abilities of metasurfaces,and demonstrate the relation between the information of the metasurface and its radiation pattern in the far-field region.By incorporating a general aperturemodel with uncertainty relation in L2-space,we propose a theory to predict the upper bound of information contained in the radiation pattern of a metasurface,and reveal the theoretical upper limit of orthogonal radiation states.Theproposed theory also provides guidance for inverse design of the metasurface with respect to given functionalities.Through investigation of the information of disordered-phase modulated metasurfaces,we find the information invariance(1?γ,whereγis Euler’s constant)of chaotic radiation patterns.That is to say,the information of the disordered-phase modulated radiation patterns is always equal to 1?γ,regardless of variations in size,the number of elements and the phase pattern of metasurface.This value might be the lower bound of radiation-pattern information of the metasurface,which can provide a theoretical limit for information modulation applications,including computational imaging,stealth technologies and wireless communications. 展开更多
关键词 metasurfaces differential ENTROPY RADIATION INFORMATION BOUNDS maximum ORTHOGONAL RADIATION patterns INFORMATION INVARIANCE
Risk assessment in poplar plantations:a case study from northern Iran 认领
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作者 Samaneh Namdari Kamran Adeli +1 位作者 Soleiman Mohammadi Limaei Zahra Bahramabadi 《林业研究:英文版》 SCIE CAS CSCD 2020年第4期1225-1233,共9页
Linear risk programming was used to determine the optimum cultivation pattern to increase incomes of poplar farmers.Seven clones of Populus deltoides Bartr.ex Marsh.were examined in Guilan province,northern Iran.Growt... Linear risk programming was used to determine the optimum cultivation pattern to increase incomes of poplar farmers.Seven clones of Populus deltoides Bartr.ex Marsh.were examined in Guilan province,northern Iran.Growth and price data were taken from previous research at the Safrabaste Poplar Research Station and in interviews with farmers.The Lingo software was used to analyze the data in different forms of E.The results show that when risk was considered,the optimal solution included the clones Pd63/51-x1,-Pd72/51-x3,Pd73/51-x4 and Pd79/51-x6.There was a high growth fluctuations of the clones Pd69/55-x2,Pd77.51-x5,and Pd caroliniensis-x7 and were not included in cultivation plans.Furthermore,the existing farm plans executed by local farmers,is neither profitoriented nor efficient in terms of income risk management according to risk efficient frontier.These results could help farmers with different levels of risk-aversion to select proper planting plans. 展开更多
关键词 Populus deltoides FARMERS Linear risk programming Optimum cultivation patterns
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汉文化影响下的畲族服饰纹样研究 认领
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作者 李晶 信玉峰 张守用 《广西科技师范学院学报》 2020年第3期48-50,64,共4页
畲族服饰纹样作为本民族特殊含义的图腾元素,在一定程度上受到汉族文化的影响。通过收集部分福建畲族服饰纹样实例,在题材内容、构成方式、色彩搭配、审美趣味等方面与汉族传统纹样进行对比研究,结合畲族历史源流,梳理其内在变化原因,... 畲族服饰纹样作为本民族特殊含义的图腾元素,在一定程度上受到汉族文化的影响。通过收集部分福建畲族服饰纹样实例,在题材内容、构成方式、色彩搭配、审美趣味等方面与汉族传统纹样进行对比研究,结合畲族历史源流,梳理其内在变化原因,论证了畲族服饰纹样既保留了本民族文化,又与汉文化不断融合这一在审美上的特殊价值。 展开更多
关键词 畲族服饰 纹样 汉文化
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装饰艺术图案的产生和演变 认领
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作者 李明 梁列峰 《文化艺术研究》 CSSCI 2020年第1期155-164,共10页
20世纪20-40年代,装饰艺术(Art Deco)在西方引领风潮,影响了平面美术和设计、建筑、服饰与织物等艺术领域。本文考察了装饰艺术图案的产生和演变,考察这一时期的流行趋势、艺术风格、社会文化之间的相互关系,进一步解读了装饰艺术图案... 20世纪20-40年代,装饰艺术(Art Deco)在西方引领风潮,影响了平面美术和设计、建筑、服饰与织物等艺术领域。本文考察了装饰艺术图案的产生和演变,考察这一时期的流行趋势、艺术风格、社会文化之间的相互关系,进一步解读了装饰艺术图案的文化内涵。装饰艺术图案作为重要的文化符号,激励了20世纪的装饰艺术运动,"装饰"了那个短暂和平的年代,并且影响了现当代的设计艺术。 展开更多
关键词 装饰 图案 装饰艺术 衍生 演变
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Moirépatterns arising from bilayer graphone/graphene superlattice 认领
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作者 Hu Li Raffaello Papadakis +2 位作者 Tanveer Hussain Amir Karton Jiangwei Liu 《纳米研究:英文版》 SCIE EI CAS CSCD 2020年第4期1060-1064,共5页
Moirépatterns from two-dimensional(2D)graphene heterostructures assembled via van der Waals interactions have sparked considerable interests in physics with the purpose to tailor the electronic properties of grap... Moirépatterns from two-dimensional(2D)graphene heterostructures assembled via van der Waals interactions have sparked considerable interests in physics with the purpose to tailor the electronic properties of graphene.Here we report for the first time the observation of moire patterns arising from a bilayer graphone/graphene superlattice produced through direct single-sided hydrogenation of a bilayer graphene on substrate.Compared to pristine graphene,the bilayer superlattice exhibits a rippled surface and two types of moire patterns are observed:triangular and linear moire patterns with the periodicities of 11 nm and 8-9 nm,respectively.These moire patterns are revealed from atomic force microscopy and further confirmed by following fast Fourier transform(FFT)analysis.Density functional theory(DFT)calculations are also performed and the optimized lattice constants of bilayer superlattice heterostructure are in line with our experimental analysis.These findings show that well-defined triangular and linear periodic potentials can be introduced into the graphene system through the single-sided hydrogenation and also open a route towards the tailoring of electronic properties of graphene by various moirépotentials. 展开更多
关键词 Moire patterns graphone/graphene superlattice atomic force microscopy triangular pattern linear pattern
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