87,532 research outputs found
New Fusarium wilt resistant melon (Cucumis melo var. cantalupensis) varieties developed by dihaploidization: Sari F1, Yetisir F 1, Solmaz F1, Emin F1 and Yucel F1
No full textResearches on Galia type melon breeding was started in 1995 at Cukurova University, Turkey. The aim of this study was to develop new melon cultivars which belong to Cucumis melo var. cantalupensis group having high yield and quality, suitable for both greenhouse and open field cultivation and also resistant to race 0 and 1 of Fusarium oxysporum f. sp. melonis wilt which are common in Turkey. For this purpose 9 female parental lines were crossed with the donor male parents which are resistant to 0 and 1 races of Fusarium wilt. By this way F1 hybrids were produced, and after the first backcrosses were done, BC1 genotypes were developed. Haploid embryo inductions and haploid plant productions were obtained by pollination with irradiated pollen. These haploid plants were duplicated by colchisine treatment and dihaploid pure lines were produced. General combination ability and special combination ability tests were conducted and more than 200 F1 hybrids were developed. These hybrids were tested in open field and greenhouse conditions for many years and Sari F1 was registered in 2008, Yetisir F1, Solmaz F 1, Emin F1 and Yucel F1 were registered in 2009 by Central Certification and Registration Management of Turkish Ministry of Agriculture. These 5 varieties have some differences concerning their total and early yields, fruit size and TSSC
A new, complex hyaline larger benthic foraminifer, Bigaella orbitoidiformis n. gen. n. sp., from the upper Bartonian-Priabonian of NW Turkey
No full textThe upper Bartonian-Priabonian shallow-marine deposits in the Biga Peninsula (NW Turkey) contain some hyaline larger benthic foraminifers (LBF) with a test architecture similar to 'orbitoidiform' foraminifers, but displaying some distinctive and complex morphological features that are recorded here for the first time. These coarsely porous specimens are characterized by a flat, disc-shaped, fragile, and smooth test with a layer of equatorial chambers/chamberlets, surrounded by poorly developed lateral chamberlets, never forming a discrete layer on either side of the equatorial layer. The nepionic stage is very distinctive because the bilocular embryonic apparatus is followed by a semi-rounded, notably large auxiliary chamber with a characteristic wavy outline, and consecutive cyclical chambers. The cyclical chamber arrangement is later transformed into annular cycles with numerous, complex arcuate- to cup-shaped chamberlets, as observed in equatorial sections. Bigaella orbitoidiformis Ozcan, Mitchell, Pignatti, Simmons, and Yucel, n. gen. n. sp., is established for these specimens, and placed within the family Eoannulariidae Ferràndez-Cañadell and Serra-Kiel, emended herein. The new genus occurs together with Caudriella Haman and Huddleston and Epiannularia Caudri (both originally established from the American bioprovince) and the genus Linderina Schlumberger (found both in the Tethys and the American bioprovinces), together with other typical Western Tethyan LBFs. A comparison of the new genus with the aforementioned taxa is given. UUID: http://zoobank.org/ab917e30-86d3-4bc2-8115-d17cf75f5d79
Modeling the impact of interaction on pedestrian group motion
No full textMobile social robots aimed at interacting with and assisting humans in pedestrian areas need to understand the dynamics of pedestrian social interaction. In this work, we investigate the effect of interaction on pedestrian group motion by defining three motion models to represent (1) interpersonal-distance, (2) relative orientation and (3) absolute difference of velocities; and model them using a dataset of 12000+ pedestrian trajectories recorded in uncontrolled settings. Our contributions include: (i) Demonstrating that interaction has a prominent effect on the empirical distributions of the proposed joint motion attributes, where increasing levels of interaction lead to more regular behavior (ii) Developing analytic motion models of such distributions and reflect the effect of interaction on model parameters (iii) Detecting the social groups in a crowd with almost perfect accuracy utilizing the proposed models, despite the constant flow direction in the environment which causes unrelated pedestrians to move in a correlated way, and thus makes group recognition more difficult (iv) Estimating the level of intensity with considerable rates utilizing the proposed models
Intrinsic group behaviour II: On the dependence of triad spatial dynamics on social and personal features; and on the effect of social interaction on small group dynamics
No full textIn a follow-up to our work on the dependence of walking dyad dynamics on intrinsic properties of the group, we now analyse how these properties affect groups of three people (triads), taking also in consideration the effect of social interaction on the dynamical properties of the group. We show that there is a strong parallel between triads and dyads. Work-oriented groups are faster and walk at a larger distance between them than leisure-oriented ones, while the latter move in a less ordered way. Such differences are present also when colleagues are contrasted with friends and families; nevertheless the similarity between friend and colleague behaviour is greater than the one between family and colleague behaviour. Male triads walk faster than triads including females, males keep a larger distance than females, and same gender groups are more ordered than mixed ones. Groups including tall people walk faster, while those with elderly or children walk at a slower pace. Groups including children move in a less ordered fashion. Results concerning relation and gender are particularly strong, and we investigated whether they hold also when other properties are kept fixed. While this is clearly true for relation, patterns relating gender often resulted to be diminished. For instance, the velocity difference due to gender is reduced if we compare only triads in the colleague relation. The effects on group dynamics due to intrinsic properties are present regardless of social interaction, but socially interacting groups are found to walk in a more ordered way. This has an opposite effect on the space occupied by non-interacting dyads and triads, since loss of structure makes dyads larger, but causes triads to lose their characteristic V formation and walk in a line (i.e., occupying more space in the direction of movement but less space in the orthogonal one)
Social group behaviour of triads. Dependence on purpose and gender
No full textWe analysed a set of uninstructed pedestrian trajectories automatically tracked in a public area, and we asked a human coder to assess their group relationships. For those pedestrians who belong to the groups, we asked the coder to identify their apparent purpose of visit to the tracking area and apparent gender. We studied the quantitative dependence of the group dynamics on such properties in the case of triads (three people groups) and compared them to the two pedestrian group case (dyads), studied in a previous work. We found that the group velocity strongly depends on relation and gender for both triads and dyads, while the influence of these properties on spatial structure of groups is less clear in the triadic case. We discussed the relevance of these results to the modelling of pedestrian and crowd dynamics, and examined the possibility of the future works on this subject
Gender profiling of pedestrian dyads
No full textIn traffic safety community, behavioral differences between genders
have been attracting considerable attention in recent decades. Various empirical
studies have proven that gender has a significant relation to drivers’, cyclists’ or
pedestrians’ decision making, route choice, rule compliance, as well as risk tak-
ing/perception. However, most studies examine behavior of individuals, and only
very few consider (pedestrian) groups with different gender profiles. Therefore,
this study investigates effect of gender composition of pedestrian dyads on the
tangible dynamics, which may potentially help in automatically understanding
and interpreting higher level behaviors such as decision making. We first propose
a set of variables to represent dyads’s physical/dynamical state. Observing em-
pirical distributions, we comment on the effect of gender interplay on locomotion
preferences. In order to verify our inferences quantitatively, we propose a gender
profile recognition algorithm. Removing one variable at a time, contribution of
each variable to recognition is evaluated. Our findings indicate that height related
variables have a more strict relation to gender, followed by group velocity and
inter-personal distance. Moreover, the “male” effect on dyad motion is found to
somehow diminish when the male is paired with a female
Walk the Talk: Gestures in Mobile Interaction
No full textThis study aims at describing navigation guidelines and concerning analytic motion models for a mobile interaction robot, which moves together with a human partner. We address particularly the impact of gestures on the coupled motion of this human-robot pair. We pose that the robot needs to adjust its navigation in accordance to its gestures in a natural manner (mimicking human-human locomotion). In order to justify this suggestion, we first examine the motion patterns of real-world pedestrian dyads in accordance to 4 affective components of interaction (i.e. gestures). Three benchmark variables are derived from pedestrian trajectories and their behavior is investigated with respect to three conditions: (i) presence/absence of isolated gestures, (ii) varying number of simultaneously performed (i.e. concurring) gestures, (iii) varying size of the environment. It is observed empirically and proven quantitatively that there is a significant difference in the benchmark variables between presence and absence of the gestures, whereas no prominent variation exists in regard to the type of gesture or the number of concurring gestures. Moreover, size of the environment is shown to be a crucial factor in sustainability of the group structure. Subsequently, we propose analytic models to represent these behavioral variations and prove that our models attain significant accuracy in reflecting the distinctions. Finally, we propose an implementation scheme for integrating the analytic models to practical applications. Our results bear the potential of serving as navigation guidelines for the robot so as to provide a more natural interaction experience for the human counterpart of a robot-pedestrian group on-the-move
On the Influence of Group Social Interaction on Intrusive Behaviours
No full textHaving extensively investigated the influence of social bonding on the spatial dynamics of two-people groups (i.e. dyads), we more recently studied the impact of group social relation on the dynamics of individual pedestrians (i.e. non-groups) in their proximity, and, reciprocally, groups’ reaction to such encounters. In the present work, we extend this analysis to additionally study the effect of the groups’ intensity of social interaction (i.e. talking to each other, performing hand gestures, or maintaining eye contact) in similar situations. specifically, using trajectories of uninstructed pedestrians observed in an ecological setting, we analyse encounters between a dyad annotated with an intensity of interaction ranging from 0 (not interacting) to 3 (strongly interacting) and a non-group coming in the opposite direction. We compute the undisturbed minimum distance between them and compare it to the actual minimum distance. To account for the correlation between the intensity of interaction and the size of a group (i.e. the interpersonal distance between the group’s members), the two distances are normalized by the average size of groups with similar intensities of interaction. In line with our previous findings, we demonstrate that avoidance dynamics is more pronounced for groups with higher levels of interaction, while groups that interact less, or not at all, are more likely to be intruded into
Intrinsic group behaviour: Dependence of pedestrian dyad dynamics on principal social and personal features
No full textBeing determined by human social behaviour, pedestrian group dynamics may depend on “intrinsic properties” such as the purpose of the pedestrians, their personal relation, gender, age, and body size. In this work we investigate the dynamical properties of pedestrian dyads (distance, spatial formation and velocity) by analysing a large data set of automatically tracked pedestrian trajectories in an unconstrained “ecological” setting (a shopping mall), whose apparent physical and social group properties have been analysed by three different human coders. We observed that females walk slower and closer than males, that workers walk faster, at a larger distance and more abreast than leisure oriented people, and that inter-group relation has a strong effect on group structure, with couples walking very close and abreast, colleagues walking at a larger distance, and friends walking more abreast than family members. Pedestrian height (obtained automatically through our tracking system) influences velocity and abreast distance, both growing functions of the average group height. Results regarding pedestrian age show that elderly people walk slowly, while active age adults walk at the maximum velocity. Groups with children have a strong tendency to walk in a non-abreast formation, with a large distance (despite a low abreast distance). A cross-analysis of the interplay between these intrinsic features, taking in account also the effect of an “extrinsic property” such as crowd density, confirms these major results but reveals also a richer structure. An interesting and unexpected result, for example, is that the velocity of groups with children increases with density, at least in the low-medium density range found under normal conditions in shopping malls. Children also appear to behave differently according to the gender of the parent
Deciphering the crowd: Modeling and identification of pedestrian group motion
No full textAssociating attributes to pedestrians in a crowd is relevant for various areas like surveillance, customer profiling and service providing. The attributes of interest greatly depend on the application domain and might involve such social relations as friends or family as well as the hierarchy of the group including the leader or subordinates. Nevertheless, the complex social setting inherently complicates this task. We attack this problem by exploiting the small group structures in the crowd. The relations among individuals and their peers within a social group are reliable indicators of social attributes. To that end, this paper identifies social groups based on explicit motion models integrated through a hypothesis testing scheme. We develop two models relating positional and directional relations. A pair of pedestrians is identified as belonging to the same group or not by utilizing the two models in parallel, which defines a compound hypothesis testing scheme. By testing the proposed approach on three datasets with different environmental properties and group characteristics, it is demonstrated that we achieve an identification accuracy of 87% to 99%. The contribution of this study lies in its definition of positional and directional relation models, its description of compound evaluations, and the resolution of ambiguities with our proposed uncertainty measure based on the local and global indicators of group relation. © 2013 by the authors; licensee MDPI, Basel, Switzerland
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