Curvature-controlled defect dynamics in active systems

We have studied the collective motion of polar active particles confined to ellipsoidal surfaces. The geometric constraints lead to the formation of vortices that encircle surface points of constant curvature (umbilics). We have found that collective motion patterns are particularly rich on ellipsoids, with four umbilics where vortices tend to be located near pairs of umbilical points to minimize their interaction energy. Our results provide a new perspective on the migration of living cells, which most likely use the information provided from the curved substrate geometry to guide their collective motion.Comment: Accepted manuscript. 8 pages, 7 Figures. Movies of the motion patterns can be found at https://www.youtube.com/playlist?list=PLEsE7_tnqXZ_U258VwxES8KAJTV_eO43

Complementarity effects through dietary mixing enhance the performance of a generalist insect herbivore

The ontogenetic niche concept predicts that resource use depends on an organism’s developmental stage. This concept has been investigated primarily in animals that show differing resource use strategies as juveniles and as adults, such as amphibians. We studied resource use and performance in the grasshopper Chorthippus parallelus (Orthoptera, Acrididae) provided with food plant mixtures of either one, three or eight plant species throughout their development. C. parallelus survival and fecundity was highest in the food plant mixture with eight plant species and lowest in the treatments where only one single plant species was offered as food. C. parallelus’ consumption throughout its ontogeny depended on sex, and feeding on different plant species was dependent on a grasshopper’s developmental stage. To depict grasshopper foraging in food plant mixtures compared to foraging on single plant species, we introduce the term “relative forage total” (RFT) based on an approach used in biodiversity research by Loreau and Hector (Nature 413:548–274, 2001). RFT of grasshoppers in food plant mixtures was always higher than what would have been expected from foraging in monocultures. The increase in food consumption was due to an overall increase in feeding on plant species in mixtures compared to consumption of the same species offered as a single diet. Thus we argue that grasshopper foraging exhibits complementarity effects. Our results reinforce the necessity to consider development-related changes in insect herbivore feeding. Thorough information on the feeding ontogeny of insect herbivores could not only elucidate their nutritional ecology but also help to shed light on their functional role in plant communities

Applying Spatial Computing to Everyday Interactive Designs

In this position paper, we address the applicability of spatial computing in the field of interactive architecture. The process of designing large-scale interactive systems is cumbersome, due in fact to single design cycles (transforming ideas into prototypes) taking a period of time usually measured in months, most of it dedicated to writing the software controlling the system. As most interactive architecture projects pass through several design cycles interleaved with user studies, speeding up the generation of the needed software becomes of crucial importance. The global-to-local programming approach is in fact a perfect tool for this task. Describing complex behaviors with simple rules is rarely seen in the existing installations, the large majority employing a central computer for the control of the system. Building up on our previous experience in this area, we created HiveKit, a proof of concept allowing bridging between the two fields, giving non-specialists easy access to distributed algorithms. HiveKit is a software package which allows designers to specify the desired behavior and automatically generate and deploy the needed code on networks of embedded devices. We introduce several projects where HiveKit is employed and create an argument, based on user studies, favoring the need for large-scale adoption of such tools

Alternate Means of Digital Design Communication

This thesis reconceptualises communication in digital design as an integrated social and technical process. The friction in the communicative processes pertaining to digital design can be traced to the fact that current research and practice emphasise technical concerns at the expense of social aspects of design communication. With the advent of BIM (Building Information Modelling), a code model of communication (machine-to-machine) is inadequately applied to design communication. This imbalance is addressed in this thesis by using inferential models of communication to capture and frame the psychological and social aspects behind the communicative contracts between people. Three critical aspects of the communicative act have been analysed, namely (1) data representation, (2) data classification and (3) data transaction, with the help of a new digital design communication platform, Speckle, which was developed during this research project for this purpose. By virtue of an applied living laboratory context, Speckle facilitated both qualitative and quantitative comparisons against existing methodologies with data from real-world settings. Regarding data representation (1), this research finds that the communicative performance of a low-level composable object model is better than that of a complete and universal one as it enables a more dynamic process of ontological revision. This implies that current practice and research operates at an inappropriate level of abstraction. On data classification (2), this thesis shows that a curatorial object-based data sharing methodology, as opposed to the current file-based approaches, leads to increased relevancy and a reduction in noise (information without intent, or meaning). Finally, on data transaction (3), the analysis shows that an object-based data sharing methodology is technically better suited to enable communicative contracts between stakeholders. It allows for faster and more meaningful change-dependent transactions, as well as allow for the emergence of traceable communicative networks outside of the predefined exchanges of current practices

Support for energy-oriented design in the Australian context

There is a need for decision support tools that integrate energy simulation into early design in the context of Australian practice. Despite the proliferation of simulation programs in the last decade, there are no ready-to-use applications that cater specifically for the Australian climate and regulations. Furthermore, the majority of existing tools focus on achieving interaction with the design domain through model-based interoperability, and largely overlook the issue of process integration. This paper proposes an energy-oriented design environment that both accommodates the Australian context and provides interactive and iterative information exchanges that facilitate feedback between domains. It then presents the structure for DEEPA, an openly customisable system that couples parametric modelling and energy simulation software as a means of developing a decision support tool to allow designers to rapidly and flexibly assess the performance of early design alternatives. Finally, it discusses the benefits of developing a dynamic and concurrent performance evaluation process that parallels the characteristics and relationships of the design process

Estimating offsets for avian displacement effects of anthropogenic impacts

Biodiversity offsetting, or compensatory mitigation, is increasingly being used in temperate grassland ecosystems to compensate for unavoidable environmental damage from anthropogenic developments such as transportation infrastructure, urbanization, and energy development. Pursuit of energy independence in the United States will expand domestic energy production. Concurrent with this increased growth is increased disruption to wildlife habitats, including avian displacement from suitable breeding habitat. Recent studies at energy-extraction and energy-generation facilities have provided evidence for behavioral avoidance and thus reduced use of habitat by breeding waterfowl and grassland birds in the vicinity of energy infrastructure. To quantify and compensate for this loss in value of avian breeding habitat, it is necessary to determine a biologically based currency so that the sufficiency of offsets in terms of biological equivalent value can be obtained. We describe a method for quantifying the amount of habitat needed to provide equivalent biological value for avifauna displaced by energy and transportation infrastructure, based on the ability to define five metrics: impact distance, impact area, pre-impact density, percent displacement, and offset density. We calculate percent displacement values for breeding waterfowl and grassland birds and demonstrate the applicability of our avian-impact offset method using examples for wind and oil infrastructure. We also apply our method to an example in which the biological value of the offset habitat is similar to the impacted habitat, based on similarity in habitat type (e.g., native prairie), geographical location, land use, and landscape composition, as well as to an example in which the biological value of the offset habitat is dissimilar to the impacted habitat. We provide a worksheet that informs potential users how to apply our method to their specific developments and a framework for developing decision-support tools aimed at achieving landscape-level conservation goals

Multi-Agents Implementation Frameworks - An Overview

Large scale deployment of Micro Grids besides the advanced metering, demand response, reliable communications infrastructure set up has been incorporated into the technological road map of the future smart power grid. To congregate the operation and control needs of distributed energy resources in Micro-Grids the Multi-Agent System (MAS) seem to have splendid features. MAS is an emerging sub-field of Distributed Artificial Intelligence that has the potential to manage the changing face of electric power grid by inculcating intelligent agents into Micro-Grids. To create agents and implement MAS a framework, a platform is obligatory where in the agents reside and operate from. There is a wide range of Multi-agent platforms available on the web like Aglet, Grasshopper, DESIRE, Jadex, ZEUS, JADE etc. Each agent platform has to be evaluated according to the some criteria that have been mentioned in this endeavor. A brief relative appraisal of an assortment of agent platforms has been provided. According to various noteworthy researches the most used platform in micro-grid applications is JADE. This paper presents an architectural and functional overview of the agent building toolkit JADE framework for Multi-Agent System implementation. DOI: 10.17762/ijritcc2321-8169.150210

The Biology, Ecology, and Management of the Migratory Grasshopper, \u3ci\u3eMelanoplus sanguinipes\u3c/i\u3e (Fab.)

Grasshoppers have caused significant damage to crops of farmers and rangeland forage of ranchers throughout history. Populations of grasshoppers can build and explode with exponential growth under the right climatic factors and habitat. Melanoplus sanguinipes is the most economic species of grasshopper in the United States. The migratory flight capabilities are very similar to true locusts. This species has been known to travel distances of over 500 miles. Millions of dollars in damage occurs to crops and rangeland annually in the United States due to this species and other economic grasshopper species. The life history of this species and timing of control measures are critical in the suppression of populations to safeguard crops and rangeland. Various techniques are employed to survey, detect, and treat grasshoppers. One of the most cost-effective methods of treatment is to use Reduced Agent-Area treatments versus blanket coverage treatments

The Biology, Ecology, and Management of the Migratory Grasshopper, \u3ci\u3eMelanoplus sanguinipes\u3c/i\u3e (Fab.)

Grasshoppers have caused significant damage to crops of farmers and rangeland forage of ranchers throughout history. Populations of grasshoppers can build and explode with exponential growth under the right climatic factors and habitat. Melanoplus sanguinipes is the most economic species of grasshopper in the United States. The migratory flight capabilities are very similar to true locusts. This species has been known to travel distances of over 500 miles. Millions of dollars in damage occurs to crops and rangeland annually in the United States due to this species and other economic grasshopper species. The life history of this species and timing of control measures are critical in the suppression of populations to safeguard crops and rangeland. Various techniques are employed to survey, detect, and treat grasshoppers. One of the most cost-effective methods of treatment is to use Reduced Agent-Area treatments versus blanket coverage treatments

The structure of feeding behavior in a phytophagous insect (Hylobius abietis)

Analysis of the feeding behavior of animals using such a high temporal resolution that meals can be defined may improve our understanding of the mechanisms regulating feeding. Meals can be distinguished in an ethologically meaningful manner by using the ‘meal criterion’, the shortest non-feeding interval between feeding bouts recognized as meals. However, such a criterion has only been determined for a few insect species. Applying a recent method developed for assessing meal criteria for vertebrates, we determined the meal criterion for Hylobius abietis (L.) (Coleoptera: Curculionidae) based on data from video recordings of single individuals feeding on seedlings of Norway spruce, Picea abies (L.) Karst. (Pinaceae). The pine weevil is an economically important pest insect because it feeds on the stem bark of planted conifer seedlings. Weevils had 4-5 meals per day. Each meal lasted about 24 min during which about 13 mm2 of bark per meal were removed. Females had longer total meal durations and longer non-feeding intervals within meals than males. Girdling seedlings did not affect the weevils’ feeding properties. The size of meals was significantly correlated to the duration of non-feeding intervals before and after them. This study is one of few describing the feeding behavior of an insect at a temporal resolution that allows individual meals to be distinguished. With more meal-related data from insects available, differences in meal properties may be interpreted based on phylogeny, ecology, and physiology. Our results may also assist in the setup and interpretation of studies of plant-insect interactions, and facilitate the evaluation and development of methods to protect plants against herbivores