Stigmergy, Self-Organization, and Sorting in Collective Robotics

Many structures built by social insects are the outcome of a process of self-organization, in which the repeated actions of the insects interact over time with the changing physical environment to produce a characteristic end state. A major mediating factor is stigmergy, the elicitation of specific environment-changing behaviors by the sensory effects of local environmental changes produced by previous behavior. A typical task involving stigmergic self-organization is brood sorting: Many ant species sort their brood so that items at similar stages of development are grouped together and separated from items at different stages of development. This article examines the operation of stigmergy and self-organization in a homogeneous group of physical robots, in the context of the task of clustering and sorting Frisbees of two different types. Using a behavioral rule set simpler than any yet proposed for ant sorting, and having no capacity for spatial orientation or memory, the robots are able to achieve effective clustering and sorting showing all the signs of self-organization. It is argued that the success of this demonstration is crucially dependent on the exploitation of real-world physics, and that the use of simulation alone to investigate stigmergy may fail to reveal its power as an evolutionary option for collective life forms.

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Southern Ocean environmental changes: effects on seabird, seal and whale populations

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1992.0152 ◽

1992 ◽

Vol 338 (1285) ◽

pp. 319-328 ◽

Cited By ~ 78

Keyword(s):

Physical Environment ◽

Environmental Changes ◽

Southern Oscillation ◽

Biological Processes ◽

Sea Ice Extent ◽

Top Predators ◽

Different Types ◽

Antarctic Continent ◽

Over Exploitation ◽

The Antarctic

The main changes in the distribution and abundance of marine top predators in the Antarctic in the last two centuries were caused by hum an over-exploitation. Hypotheses that increases in populations of krill-eating penguins and seals represent recovery from exploitation, accelerated by removal of krill-eating whales, are being re-evaluated in the light of correlations between population size and reproductive success of seabirds and seals and various features of the biological and physical environment. These correlations involve phocid and otariid seals, penguins and flying birds and sites ranging from the Antarctic continent to sub-Antarctic islands. Although the nature of, and balance between, physical and biological influences differ between sites, regions and different types of predator, processes (including potentially important links with the Southern Oscillation) involving sea-ice extent and distribution play a key role. Major uncertainties over the nature of the links between physical and biological processes and the responses of marine populations preclude any confident prediction of the potential effects of future environmental change. However, certain taxa, especially those of specialist ecology, extreme demography and restricted distribution (especially in high latitudes) are especially vulnerable to at least some of the likely environmental changes.

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Physical environment and daily life in the Sanctuary of Poseidon at Kalaureia, Poros. The bioarchaeological remains

Opuscula Annual of the Swedish Institutes at Athens and Rome ◽

10.30549/opathrom-12-03 ◽

2019 ◽

pp. 159-172 ◽

Cited By ~ 7

Author(s):

Arto Penttinen ◽

Dimitra Mylona

Keyword(s):

Everyday Life ◽

Physical Environment ◽

Daily Life ◽

Soil Samples ◽

Crucial Importance ◽

Archaeological Excavation ◽

Research Project ◽

The Everyday ◽

Over Time

The section below contains reports on bioarchaeological remains recovered in the excavations in Areas D and C in the Sanctuary of Poseidon at Kalaureia, Poros, between 2003 and 2005. The excavations were directed by the late Berit Wells within a research project named Physical Environment and Daily Life in the Sanctuary of Poseidon at Kalaureia (Poros). The main objective of the project was to study what changed and what remained constant over time in the everyday life and in both the built and physical environment in an important sanctuary of the ancient Greeks. The bioarchaeological remains, of a crucial importance for this type of study, were collected both by means of traditional archaeological excavation and by processing extensively collected soil samples. This text aims to providing the theoretical and archaeological background for the analyses that follow.

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Measuring Agency Change Across the Domain of Hypnosis

10.31234/osf.io/apceh ◽

2019 ◽

Author(s):

Vince Polito ◽

Amanda Barnier ◽

Erik Woody

Keyword(s):

Rating Scale ◽

Sense Of Agency ◽

Pass Rates ◽

Current Experiment ◽

Multidimensional Construct ◽

Time Points ◽

Hypnotic Induction ◽

Different Types ◽

Over Time ◽

Postexperimental Inquiry

Building on Hilgard’s (1965) classic work, the domain of hypnosis has been conceptualised by Barnier, Dienes, and Mitchell (2008) as comprising three levels: (1) classic hypnotic items, (2) responding between and within items, and (3) state and trait. The current experiment investigates sense of agency across each of these three levels. Forty-six high hypnotisable participants completed an ideomotor (arm levitation), a challenge (arm rigidity) and a cognitive (anosmia) item either following a hypnotic induction (hypnosis condition) or without a hypnotic induction (wake condition). In a postexperimental inquiry, participants rated their feelings of control at three time points for each item: during the suggestion, test and cancellation phases. They also completed the Sense of Agency Rating Scale (Polito, Barnier, & Woody, 2013) for each item. Pass rates, control ratings, and agency scores fluctuated across the different types of items and for the three phases of each item; also, control ratings and agency scores often differed across participants who passed versus failed each item. Interestingly, whereas a hypnotic induction influenced the likelihood of passing items, it had no direct effect on agentive experiences. These results suggest that altered sense of agency is not a unidimensional or static quality “switched on” by hypnotic induction, but a dynamic multidimensional construct that varies across items, over time and according to whether individuals pass or fail suggestions.

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Enzyme Immobilization on Nanomaterials for Biosensor and Biocatalyst in Food and Biomedical Industry

Current Pharmaceutical Design ◽

10.2174/1381612825666190712181403 ◽

2019 ◽

Vol 25 (24) ◽

pp. 2661-2676 ◽

Cited By ~ 1

Author(s):

Sundaresan Bhavaniramya ◽

Ramar Vanajothi ◽

Selvaraju Vishnupriya ◽

Kumpati Premkumar ◽

Mohammad S. Al-Aboody ◽

...

Keyword(s):

Enzyme Activity ◽

Enzyme Immobilization ◽

Food Industry ◽

Environmental Changes ◽

Immobilized Enzymes ◽

Food Industries ◽

Physiological Processes ◽

Different Types ◽

Simple Processing ◽

Biomedical Industry

Enzymes exhibit a great catalytic activity for several physiological processes. Utilization of immobilized enzymes has a great potential in several food industries due to their excellent functional properties, simple processing and cost effectiveness during the past decades. Though they have several applications, they still exhibit some challenges. To overcome the challenges, nanoparticles with their unique physicochemical properties act as very attractive carriers for enzyme immobilization. The enzyme immobilization method is not only widely used in the food industry but is also a component methodology in the pharmaceutical industry. Compared to the free enzymes, immobilized forms are more robust and resistant to environmental changes. In this method, the mobility of enzymes is artificially restricted to changing their structure and properties. Due to their sensitive nature, the classical immobilization methods are still limited as a result of the reduction of enzyme activity. In order to improve the enzyme activity and their properties, nanomaterials are used as a carrier for enzyme immobilization. Recently, much attention has been directed towards the research on the potentiality of the immobilized enzymes in the food industry. Hence, the present review emphasizes the different types of immobilization methods that is presently used in the food industry and other applications. Various types of nanomaterials such as nanofibers, nanoflowers and magnetic nanoparticles are significantly used as a support material in the immobilization methods. However, several numbers of immobilized enzymes are used in the food industries to improve the processing methods which not only reduce the production cost but also the effluents from the industry.

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Imagery in the Book of Revelation

The Oxford Handbook of the Book of Revelation ◽

10.1093/oxfordhb/9780190655433.013.3 ◽

2020 ◽

pp. 52-67

Author(s):

Konrad Huber

Keyword(s):

Reception History ◽

Book Of Revelation ◽

Imperial Cult ◽

Emotional Effect ◽

Greco Roman ◽

Different Types ◽

Figurative Speech ◽

Theological Message ◽

Over Time ◽

The Way

The chapter first surveys different types of figurative speech in Revelation, including simile, metaphor, symbol, and narrative image. Second, it considers the way images are interrelated in the narrative world of the book. Third, it notes how the images draw associations from various backgrounds, including biblical and later Jewish sources, Greco-Roman myths, and the imperial cult, and how this enriches the understanding of the text. Fourth, the chapter looks at the rhetorical impact of the imagery on readers and stresses in particular its evocative, persuasive, and parenetic function together with its emotional effect. And fifth, it looks briefly at the way reception history shows how the imagery has engaged readers over time. Thus, illustrated by numerous examples, it becomes clear how essentially the imagery of the book of Revelation constitutes and determines its theological message.

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Effect of scent on comfort of aircraft passengers

Work ◽

10.3233/wor-208025 ◽

2021 ◽

Vol 68 (s1) ◽

pp. S273-S280

Author(s):

Xinhe Yao ◽

Yu Song ◽

Peter Vink

Keyword(s):

Completion Time ◽

Aircraft Cabin ◽

Different Types ◽

The Relationship ◽

Over Time

BACKGROUND: Scents may influence the perceived comfort of an environment. There are only a few studies conducted on the relationship between scent and comfort in aircraft cabin. OBJECTIVES: The goal of this research is to explore whether relationships between scents and perceived comfort can be found for passengers in an aircraft cabin. METHODS: 276 participants joined an experiment in a Boeing 737 fuselage. The participants were divided into nine groups and each joined a session for 60 minutes with the exposure to different scents. The effect of the odor was measured by a set of questionnaires at the beginning and at the end of the session. Results of questionnaires were analyzed regarding the effects on the completion time, of the type of scents, of the intensity of the scent and on gender. RESULTS: Significant differences were found at the beginning and at the end of the experiment regarding comfort and emotion, but sometimes no relations could be established. The influence of different scents on comfort/discomfort varied and changed over time. However, in all scenarios, participant’ scores on emotion decreased. Additionally, the added scents influenced the linearity between the changes in comfort and discomfort. CONCLUSIONS: Smell could influence the perceived comfort/discomfort of aircraft passengers over time, and different types of smells have different effects on passengers. The preferences on scents are diverse, which highlights the need for personalization in aircraft cabin design.

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When physical activity meets the physical environment: precision health insights from the intersection

Environmental Health and Preventive Medicine ◽

10.1186/s12199-021-00990-w ◽

2021 ◽

Vol 26 (1) ◽

Author(s):

Luisa V. Giles ◽

Michael S. Koehle ◽

Brian E. Saelens ◽

Hind Sbihi ◽

Chris Carlsten

Keyword(s):

Physical Activity ◽

Physical Environment ◽

Environmental Changes ◽

Main Body ◽

Or Groups ◽

Optimizing Design ◽

Physical Activity Recommendations ◽

The Individual ◽

Precision Health ◽

Activity Recommendations

Abstract Background The physical environment can facilitate or hinder physical activity. A challenge in promoting physical activity is ensuring that the physical environment is supportive and that these supports are appropriately tailored to the individual or group in question. Ideally, aspects of the environment that impact physical activity would be enhanced, but environmental changes take time, and identifying ways to provide more precision to physical activity recommendations might be helpful for specific individuals or groups. Therefore, moving beyond a “one size fits all” to a precision-based approach is critical. Main body To this end, we considered 4 critical aspects of the physical environment that influence physical activity (walkability, green space, traffic-related air pollution, and heat) and how these aspects could enhance our ability to precisely guide physical activity. Strategies to increase physical activity could include optimizing design of the built environment or mitigating of some of the environmental impediments to activity through personalized or population-wide interventions. Conclusions Although at present non-personalized approaches may be more widespread than those tailored to one person’s physical environment, targeting intrinsic personal elements (e.g., medical conditions, sex, age, socioeconomic status) has interesting potential to enhance the likelihood and ability of individuals to participate in physical activity.

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Canadian Exceptionalism: Explaining Differences over Time in Provincial and Federal Voter Turnout

Canadian Journal of Political Science ◽

10.1017/s0008423901777918 ◽

2001 ◽

Vol 34 (2) ◽

pp. 299-319 ◽

Cited By ~ 4

Author(s):

Donley T. Studlar

Keyword(s):

Regression Analysis ◽

Population Density ◽

Multiple Regression Analysis ◽

Voter Turnout ◽

The Political ◽

Federal Level ◽

Industrial Democracies ◽

Different Types ◽

Over Time ◽

Cross National

Canada is unusual among advanced industrial democracies in having some provinces which regularly have greater voter turnouts for provincial than for federal elections. Provincial and federal turnouts by province in Canada are analyzed for the 1945-1998 period using multiple regression analysis, both for each set of elections and by comparing differences between the two. Federal turnout has declined over the years but provincial turnout appears to have increased slightly. Although the effects found here largely confirm previous findings about the relative effects of different types of variables found for the Canadian federal level only, several of the political explanations previously supported in cross-national research find less support. Instead, region, population density, months since the last federal or provincial election, and season of the year generally have greater and sometimes more consistent effects. This suggests the need for more studies of turnout in democracies at sub-central levels.

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