A Prospect-Refuge Approach to Seat Preference: Environmental psychology and spatial layout

The interplay between mind, behaviour and world has been extensively examined by the field of environmental psychology. This approach investigates the ways in which environment furnishes human spatial behaviour as well as individual’s responses to information retrieved by his or her immediate stimuli. Despite the fact that scholarly work in this field has provided valuable conclusions about social functioning in various spatial settings, the spatial context is usually conceptualised as if unstructured and without distinctive physical or organisational properties as a spatial whole. For these reasons several approaches from the built environment tried to address this gap by combining space syntax theoretical and methodological tools with key concepts from the field of environmental psychology and examined spatial cognition, movement, wayfinding, navigation and visual perception. This paper aims at contributing to this existing body of literature by drawing on Appleton’s (1975) prospect-refuge theory and examining stationary activities such as seat preference. The coffee shop like settings of three customer lounges in the UK serve as empirical case studies to investigate customers’ seat preferences. The methodology implemented for this study combines a consistent analysis of spatial structures captured by space syntax analytical tools with behavioural data retrieved by detailed onsite observations of space usage. Furniture settings were mapped and classified according to orientation of seats (‘directness’), presence or absence of attractors (such as windows, TV, coffee bar) and furniture types (armchairs, sofas, booths, etc.). This study found that there is no linear relationship of occupancy with spatial variables and that various contributing factors determine seat selection. In essence, seat preference is rendered as a rather complex phenomenon which depends on the degree of control that is given to the occupant, furniture type as well as furniture directness. At the same time, the paper develops joint metrics that aim at tackling Appleton’s concept of prospect-refuge. In summary, this research by adopting a more empirical and behavioural approach centred on seating preferences presents an innovative way of jointly analysing spatial variables alongside space usage preferences for the examination of stationary activities

Macroscopic limit cycle via pure noise-induced phase transition

Bistability generated via a pure noise-induced phase transition is reexamined from the view of bifurcations in macroscopic cumulant dynamics. It allows an analytical study of the phase diagram in more general cases than previous methods. In addition using this approach we investigate patially-extended systems with two degrees of freedom per site. For this system, the analytic solution of the stationary Fokker-Planck equation is not available and a standard mean field approach cannot be used to find noise induced phase transitions. A new approach based on cumulant dynamics predicts a noise-induced phase transition through a Hopf bifurcation leading to a macroscopic limit cycle motion, which is confirmed by numerical simulation.Comment: 8 pages, 8 figure

Noise Induced Complexity: From Subthreshold Oscillations to Spiking in Coupled Excitable Systems

We study stochastic dynamics of an ensemble of N globally coupled excitable elements. Each element is modeled by a FitzHugh-Nagumo oscillator and is disturbed by independent Gaussian noise. In simulations of the Langevin dynamics we characterize the collective behavior of the ensemble in terms of its mean field and show that with the increase of noise the mean field displays a transition from a steady equilibrium to global oscillations and then, for sufficiently large noise, back to another equilibrium. Diverse regimes of collective dynamics ranging from periodic subthreshold oscillations to large-amplitude oscillations and chaos are observed in the course of this transition. In order to understand details and mechanisms of noise-induced dynamics we consider a thermodynamic limit $N\to\infty$ of the ensemble, and derive the cumulant expansion describing temporal evolution of the mean field fluctuations. In the Gaussian approximation this allows us to perform the bifurcation analysis; its results are in good agreement with dynamical scenarios observed in the stochastic simulations of large ensembles

Impact of system parameter selection on radar sensor performance in automotive applications

The paper deals with the investigation of relevant boundary conditions to be considered in order to operate 77/79 GHz narrow and ultra wide band automotive radar sensors in the automotive platform and the automotive environment

Human versus machine - testing validity and insights of manual and automated data gathering methods in complex buildings

With the advancement of information technologies, automated methods of gathering data on space usage patterns in complex buildings using sensors are gaining popularity. At the same time, typical Space Syntax studies still rely on traditional social science methods and manual data gathering, for instance through direct observations and user surveys. How insights generated by each approach compare to each other is still poorly understood. Therefore this paper reports findings from an in-depth two week long study of space usage in a university building, where both manual methods (direct observations, user surveys) and automated data gathering methods (RFID sensors recording locations and interactions of users) were employed in parallel. The main hypotheses to be tested are that automated data captured by RFID sensors delivers comparable findings (1), complementary findings (2) or contradictory findings (3) to direct observations and self-reported surveys. The user behaviour under investigation includes movement flows, patterns of occupancy, interactivity and interaction networks. Results suggest that variable degrees of overlap can be established between the two approaches with rather few comparable findings. For certain space usage behaviours high levels of variance between the automated and manual datasets are found, pointing towards predominantly complementary and contradictory findings. It is shown that the goodness of the fit between automated and manual data depends on the way data is aggregated. This allows systematic reflections on the strengths and weaknesses of each of the approaches. In summary, evidence suggests that both human and machine based data gathering reveal crucial insights into behaviours of building users. Substituting manual methods with automated ones cannot be supported by the data of this study. Further suggestions for future studies of social life in complex buildings are made, thus contributing to the development of research methods in the field

Collapse of Flux Tubes

The dynamics of an idealized, infinite, MIT-type flux tube is followed in time as the interior evolves from a pure gluon field to a $\overline q \ q$ plasma. We work in color U(1). $\overline q\ q$ pair formation is evaluated according to the Schwinger mechanism using the results of Brink and Pavel. The motion of the quarks toward the tube endcaps is calculated by a Boltzmann equation including collisions. The tube undergoes damped radial oscillations until the electric field settles down to zero. The electric field stabilizes the tube against pinch instabilities; when the field vanishes, the tube disintegrates into mesons. There is only one free parameter in the problem, namely the initial flux tube radius, to which the results are very sensitive. Among various quantities calculated is the mean energy of the emitted pions.Comment: 16 pages plus 12 figures. RevTex3. DOE/ER/40427-160N9

On-site Cytology for Development of Patient-Derived Three-dimensional Organoid Cultures - A Pilot Study

BACKGROUND/AIM Development of patient-derived three-dimensional (3D) organoid cultures is an emerging technique in the field of precision oncology. We aimed to integrate on-site adequacy evaluation using cytology into the tumor organoid development workflow to ensure precise characterization and growth of these cultures. PATIENTS AND METHODS Cancer patients were consented to a Precision Medicine trial. Fresh tissue was procured for genomic analyses as well as organoid development. Fresh tissue destined for organoid development was evaluated by preparing on-site cytology smears to ensure that only lesional tissue would be submitted for further cell culture work. RESULTS Cytology preparations were made from 64 different tumor samples and evaluated prior to tissue submission for organoid development. In 53 (82.2%) of those tumor samples, the cytology preparation was diagnostic, thus providing adequate material for organoid development. CONCLUSION Characterizing the tissue prior to submission for organoid development ensures submission of lesional tissue only. Furthermore, it is a cost-effective method that can help document patient diagnosis. This can be of importance in biopsies, since the tissue submitted for organoid development cannot be retrieved for clinical diagnosis afterwards. Our findings in this pilot study led to the implementation of on-site cytological evaluation in the tumor organoid development workflow at the Englander Institute for Precision Medicine, NY, USA