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91.
Yin Bao Lie Tang Matthew W. Breitzman Maria G. Salas Fernandez Patrick S. Schnable 《野外机器人技术杂志》2019,36(2):397-415
Sorghum (Sorghum bicolor) is known as a major feedstock for biofuel production. To improve its biomass yield through genetic research, manually measuring yield component traits (e.g. plant height, stem diameter, leaf angle, leaf area, leaf number, and panicle size) in the field is the current best practice. However, such laborious and time‐consuming tasks have become a bottleneck limiting experiment scale and data acquisition frequency. This paper presents a high‐throughput field‐based robotic phenotyping system which performed side‐view stereo imaging for dense sorghum plants with a wide range of plant heights throughout the growing season. Our study demonstrated the suitability of stereo vision for field‐based three‐dimensional plant phenotyping when recent advances in stereo matching algorithms were incorporated. A robust data processing pipeline was developed to quantify the variations or morphological traits in plant architecture, which included plot‐based plant height, plot‐based plant width, convex hull volume, plant surface area, and stem diameter (semiautomated). These image‐derived measurements were highly repeatable and showed high correlations with the in‐field manual measurements. Meanwhile, manually collecting the same traits required a large amount of manpower and time compared to the robotic system. The results demonstrated that the proposed system could be a promising tool for large‐scale field‐based high‐throughput plant phenotyping of bioenergy crops. 相似文献
92.
A. Dal Bosco Zs. Gerencsér Zs. Szendrő C. Mugnai M. Cullere M. Kovàcs S. Ruggeri S. Mattioli C. Castellini A. Dalle Zotte 《Meat science》2014
The objective of this study was to evaluate the effect of Spirulina and Thyme supplementation on rabbit meat during retail display. At weaning 294 rabbits were allocated to 7 different treatments (42 rabbits/treatment). Rabbits of the control group (C) received a diet without any supplementation throughout the experiment (5–11 weeks of age). The other groups were fed diets containing 5% Spirulina (S), 3% Thyme (T) or both supplements (ST) for the whole trial (5–11 weeks; treatments S, T and ST), or for a part of the growing period (8–11 weeks; treatments C–S, C–T and C–ST). Colour parameters, pH, water holding capacity and drip loss were determined on fresh and stored Longissimus dorsi muscle of 5 rabbits/treatment. Spirulina- and Thyme-supplemented diets had a significant effect on redness and yellowness of Longissimus dorsi. Drip loss was significantly reduced in C–T and T groups that also showed the highest content of α-tocopherol and n − 3 fatty acids content and the lower lipid oxidation. 相似文献
93.
Viswanath Venkatesh Tracy Ann Sykes Srinivasan Venkatraman 《Information Systems Journal》2014,24(3):249-269
Electronic government (e‐Government) is one of the most important ways to bridge the digital divide in developing countries. We develop a model of e‐Government portal use. We use various individual characteristics, namely demographics and personality, as predictors of e‐Government portal use. Specifically, our predictors were (1) gender, age, income and education; (2) the Big Five personality characteristics, i.e. extraversion, neuroticism, conscientiousness, agreeableness and openness to experience; and (3) personal innovativeness with information technology. We conducted a field study in a village in India. We collected data from over 300 heads of household. We found support for our model, with most variables being significant and explaining 40% of the variance in e‐Government portal use. 相似文献
94.
This study focuses on an emerging media multitasking phenomenon called second screening or dual screening. Employing two-wave panel-data from 19 countries, we test whether the Big Five personality traits help explain the use of an additional screen or device while watching political content on TV to discuss the program with others or to look up for additional information. Results show that extraversion positively predicts political second screening. In contrast, agreeableness and openness to new experience are negatively related to political second screening. Moreover, multilevel analysis is performed to test whether the between-country variation is related to economic, political and cultural indicators. 相似文献
95.
96.
Karolina W. Cynk 《Civil Engineering and Environmental Systems》2017,34(2):104-126
The aim of this article was to characterise and compare the level of environmental intelligence among university students from selected countries of Central and Eastern Europe. This was done using empirical data collected by the author in 2015. In the introduction and theoretical part of this text, the term ‘environmental intelligence’ is defined, and issues raised by modern sociologists such as M. Maffesoli and M. Archer are presented. Two hypotheses stating that respondents from Poland, Slovakia and Czech Republic have higher levels of environmental intelligence than university students from the Ukraine, and those studying natural sciences have higher levels of environmental intelligence than students of the humanities or social sciences were verified. The statistical analysis conducted in the second part of the text revealed a higher level of environmental intelligence among students from the European Union countries compared to respondents from the Ukraine. However, there were no significant differences between the level of environmental intelligence and respondents’ faculty of studies. This indicates that studying natural sciences did not contribute to a more dynamic development of environmental intelligence in students. This revelation may be disturbing, as the state of the environment cannot improve if young people cannot use and care for it responsibly. 相似文献
97.
Despite the crucial role of color appearance in forming first impressions, it is still not clear how color evokes personality associations—that is, a color‐personality association (CPA). This study aims to propose a method for quantifying the relationships between color attributes and CPAs for single colors. Specifically, we first collected the CPAs of five traits evoked by single colors (i.e., extraverted–introverted, moody–unemotional, agreeable–disagreeable, organized–disorganized, and wide interests–narrow interests) in a carefully controlled experiment. Then, multiple linear regression (MLR) analyses were adopted to predict these CPAs based on three color attributes (lightness, chroma, and hue). Our results showed that (1) the personality associations could be evoked by colors and perceived consistently by observers; (2) the relationships between the color attributes and the CPAs could be well quantified by separately conducting MLR analyses in different regions of hue (i.e., red, green, blue, and yellow regions); and (3) both lightness and chroma were significant predictors in almost all predictive models and they might have different relative importance or directions of effect when predicting the CPAs in different regions of hue, even for the same trait. This study improves the understanding of how color evokes personality associations and takes the first step toward developing the method for predicting the CPAs for multicolor combinations. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 388–396, 2017 相似文献
98.
Status updates represent a new form of one-to-many communication which is widely used among members of social networking sites (SNS). The present study investigated the question of who in particular uses the self-presentational opportunities of this feature and which users engage in riskier self-disclosures than others. Combining questionnaire and content analysis, we related self-reports on users’ personality traits (extraversion, narcissism, self-efficacy, need to belong, need for popularity) to the actual use of Facebook status updates. Results showed that higher degrees of narcissism led to deeper self-disclosures and more self-promotional content within these messages. Users with higher need to belong disclosed more intimate information in status updates, while perceived efficacy of self-presentation was negatively related to the mass suitability of postings. Findings extend prior research on personality and SNS usage with regard to dynamic features and content differences in online self-presentation. 相似文献
99.
The current study identified and examined perceived self-traits and behavioral traits as antecedents of online empathic experiences and prosocial behavior. Our findings suggest that perceived self-traits (i.e., self-efficacy in online relationship and self-disclosure) are strongly associated with both empathic experiences and prosocial behavior. Findings for the behavioral trait, interaction pattern of an individual, indicate that patterns of an individual's networking produce mixed results in regard to association with prosocial behavior. Bonding networking was found to positively predict prosocial behavior, while bridging networking showed a negative association with the same dependent measure. Identity discrepancy and writing activities were also found to positively affect prosocial behavior. Overall, the finding of this study indicates that perceived self-traits tend to display stronger explanatory power over both empathy and prosocial behavior than do behavioral traits. 相似文献
100.
砚滴,历史悠远,居文房用具第七位。其材质繁多,形制各异。其中,陶瓷砚滴极其工巧,它既诠释着中国陶瓷业的发展历史,也传承了几千年的中华文明。本文首先把陶瓷砚滴的发展大致划分为四个阶段,然后分别探讨其历史背景、形制与特征。 相似文献