Multi-agent collaborative search : an agent-based memetic multi-objective optimization algorithm applied to space trajectory design

This article presents an algorithm for multi-objective optimization that blends together a number of heuristics. A population of agents combines heuristics that aim at exploring the search space both globally and in a neighbourhood of each agent. These heuristics are complemented with a combination of a local and global archive. The novel agent-based algorithm is tested at first on a set of standard problems and then on three specific problems in space trajectory design. Its performance is compared against a number of state-of-the-art multi-objective optimization algorithms that use the Pareto dominance as selection criterion: non-dominated sorting genetic algorithm (NSGA-II), Pareto archived evolution strategy (PAES), multiple objective particle swarm optimization (MOPSO), and multiple trajectory search (MTS). The results demonstrate that the agent-based search can identify parts of the Pareto set that the other algorithms were not able to capture. Furthermore, convergence is statistically better although the variance of the results is in some cases higher

Varieties and Pre Harvesting Treatment for Growing Polish Canola (Brassica rapa L.) in Interior Alaska

Abstract Barley has been a mono cereal crop grown in the Delta Junction area of Alaska since 1970s. A rotational crop is needed for weed control and conservation tillage for sustainable crop production. Due to short growing season constrains, canola when used as a rotational crop currently resulted low marketability because of high green seed content (>2%). The objective of this research is to determine if glyphosate when used as a desiccating chemical could promote early maturity and reduce green seed content of canola. Four Polish canola cultivars were treated with direct combine (as a control), pushing (to stop growth) and desiccating in two locations in Alaska USA in a randomized complete block design with four replicates from 2007 to 2009. Glyphosate was sprayed, and pushing was conducted around August 15 each year. Results showed that 'Hysin 110' treated by glyphosate consistently had ≤ 2% green seed content in three years in contrast with 'Reward' despite a wide variation of weather conditions. The growing degree days were dramatically different among the three years, with 2009 close to the 29-year norm, 2008 was lower and 2007 was higher than the norm. No residual glyphosate was found in the seeds from the desiccating treatment. In conclusion, desiccating treatment together with a good short growing season Polish canola cultivar can make canola grown as a rotational crop in Alaska's short growing season conditions

Sex pheromone signal and stability covary with fitness

If sexual signals are costly, covariance between signal expression and fitness is expected. Signal–fitness covariance is important, because it can contribute to the maintenance of genetic variation in signals that are under natural or sexual selection. Chemical signals, such as female sex pheromones in moths, have traditionally been assumed to be species-recognition signals, but their relationship with fitness is unclear. Here, we test whether chemical, conspecific mate finding signals covary with fitness in the moth Heliothis subflexa. Additionally, as moth signals are synthesized de novo every night, the maintenance of the signal can be costly. Therefore, we also hypothesized that fitness covaries with signal stability (i.e. lack of temporal intra-individual variation). We measured among- and within-individual variation in pheromone characteristics as well as fecundity, fertility and lifespan in two independent groups that differed in the time in between two pheromone samples. In both groups, we found fitness to be correlated with pheromone amount, composition and stability, supporting both our hypotheses. This study is, to our knowledge, the first to report a correlation between fitness and sex pheromone composition in moths, supporting evidence of condition-dependence and highlighting how signal–fitness covariance may contribute to heritable variation in chemical signals both among and within individuals

Report Mid-term Review SLEEI Project

Effective Protection of Fundamental Rights in a pluralist worl

Establishing Origin: Analysing the Questions Asked in Asylum Interviews

In the absence of evidence, asylum seekers are interviewed to assess the credibility of their stories. Few studies have examined whether or not the questions asked in such interviews stimulate the applicant to give lengthy, detailed, and accurate answers. The style, type, and content of the questions asked in order to assess a claim about origin were analysed in 40 case files from the Dutch Immigration Service. A large proportion of the questions were closed and fact-checking questions. Less than one fifth of questions were open or cued recall questions. The results show that to assess credibility of origin, knowledge questions were posed about the immediate living environment, flight to Europe, identity documents, country of origin, and personal background of applicants. Possibilities for increasing the quantity and quality of information obtained in asylum interviews are discussed. Future research should validate the assumption that truthful claimants have substantial knowledge about their country and town of origin.FdR – Publicaties zonder aanstelling Universiteit Leide

Amorphous carbon film deposition on inner surface of tubes using atmospheric pressure pulsed filamentary plasma source

Uniform amorphous carbon film is deposited on the inner surface of quartz tube having the inner diameter of 6 mm and the outer diameter of 8 mm. A pulsed filamentary plasma source is used for the deposition. Long plasma filaments (~ 140 mm) as a positive discharge are generated inside the tube in argon with methane admixture. FTIR-ATR, XRD, SEM, LSM and XPS analyses give the conclusion that deposited film is amorphous composed of non-hydrogenated sp2 carbon and hydrogenated sp3 carbon. Plasma is characterized using optical emission spectroscopy, voltage-current measurement, microphotography and numerical simulation. On the basis of observed plasma parameters, the kinetics of the film deposition process is discussed