350 research outputs found

    Sub-structural Niching in Estimation of Distribution Algorithms

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    We propose a sub-structural niching method that fully exploits the problem decomposition capability of linkage-learning methods such as the estimation of distribution algorithms and concentrate on maintaining diversity at the sub-structural level. The proposed method consists of three key components: (1) Problem decomposition and sub-structure identification, (2) sub-structure fitness estimation, and (3) sub-structural niche preservation. The sub-structural niching method is compared to restricted tournament selection (RTS)--a niching method used in hierarchical Bayesian optimization algorithm--with special emphasis on sustained preservation of multiple global solutions of a class of boundedly-difficult, additively-separable multimodal problems. The results show that sub-structural niching successfully maintains multiple global optima over large number of generations and does so with significantly less population than RTS. Additionally, the market share of each of the niche is much closer to the expected level in sub-structural niching when compared to RTS

    Synthesis and Characterization of New Oxazolidin-4-one Derivatives via the Reaction of Various Some Imines with Glycolic Acid

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    New derivatives of 2,3-disubstituted- oxazolidine-4-one were synthesized by cycloaddition reaction of glycolic acid to various imines in anhydrous 1,4-dioxane under dry and reflux conditions. Imines were synthesized by acid–catalyzed thermal condensation of the amino group of aromatic amine and phenylhydrazines with the carbonyl group of aromatic aldehydes and ketones in absolute ethanol. The products were identified by C.H.N content FT-IR and 1HNMR spectr

    Path Planning for Shepherding a Swarm in a Cluttered Environment using Differential Evolution

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    Shepherding involves herding a swarm of agents (sheep) by another a control agent (sheepdog) towards a goal. Multiple approaches have been documented in the literature to model this behaviour. In this paper, we present a modification to a well-known shepherding approach, and show, via simulation, that this modification improves shepherding efficacy. We then argue that given complexity arising from obstacles laden environments, path planning approaches could further enhance this model. To validate this hypothesis, we present a 2-stage evolutionary-based path planning algorithm for shepherding a swarm of agents in 2D environments. In the first stage, the algorithm attempts to find the best path for the sheepdog to move from its initial location to a strategic driving location behind the sheep. In the second stage, it calculates and optimises a path for the sheep. It does so by using way points on that path as the sequential sub-goals for the sheepdog to aim towards. The proposed algorithm is evaluated in obstacle laden environments via simulation with further improvements achieved

    Flammability action of tires material after adding flame inhibitor

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    Magnesium hydroxide was used as flame inhibitor to increased flame resistance for tires .Magnesium hydroxide was adding with (5%,10%) weight percents to rubber master batch of tire and then exposed the resulting material to a flame generated from gas torch with (10 mm) exposure distance . Method of measuring the surface temperature opposite to the flame was used to determine the heat transferred through tire material. The results were obtained shows enhanced flame resistance for tire by added magnesium hydroxide and this resistance increased by increasing hydroxide Percentage

    Characterization of Indicators for Adaptive Human-Swarm Teaming

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    Swarm systems consist of large numbers of agents that collaborate autonomously. With an appropriate level of human control, swarm systems could be applied in a variety of contexts ranging from urban search and rescue situations to cyber defence. However, the successful deployment of the swarm in such applications is conditioned by the effective coupling between human and swarm. While adaptive autonomy promises to provide enhanced performance in human-machine interaction, distinct factors must be considered for its implementation within human-swarm interaction. This paper reviews the multidisciplinary literature on different aspects contributing to the facilitation of adaptive autonomy in human-swarm interaction. Specifically, five aspects that are necessary for an adaptive agent to operate properly are considered and discussed, including mission objectives, interaction, mission complexity, automation levels, and human states. We distill the corresponding indicators in each of the five aspects, and propose a framework, named MICAH (i.e., Mission-Interaction-Complexity-Automation-Human), which maps the primitive state indicators needed for adaptive human-swarm teaming

    The Beneficial Role of Some Bone Markers in Evaluating Women with Osteoporosis under Different Therapeutic Regimens

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    Osteoporosis is a systemic disease of the skeleton, characterized by low bone mass and alteration in the micro-architecture of the bone tissue that lead to an increase in brittleness with the ensuing predisposition to bone fracture. Global statistics shows that women are more exposed to this disease than men and in particular at menopause. This study was designed to evaluate the use of some bone markers: serum osteocalcin (Ost), alkaline phosphatase (ALP), as bone formation markers, also parathyroid hormone (PTH), calcium and inorganic phosphate level, for the assessment of patients with osteoporosis and to evaluate their role in monitoring of several types of therapeutic interventions (such as bisphosphonates, hormonal replacement therapy, and Ca and vit.D) in postmenopausal women.This study comprised of 36 women (age 51.67±5.14 years) those diagnosed to have osteoporosis, to be allocated randomly into three groups according to the type of therapy to be given as; group A: received bisphosphonates (sodium alendronate 10mg/day) for twelve weeks (N=12). group B: treated with hormonal replacement therapy (conjugated estrogen 0.625mg/day) for twelve weeks (N=12). group C: received Ca and vit. D (Ca1500mg/day and cholecalciferol 1000IU/day) for twelve weeks(N=12). In addition to 15 perimenopausal healthy women to serve as a control group (age 51.13±7.62 years).The studied parameters were measured in serum obtained before starting treatment and after 12 weeks of therapy. Result indicated that the baseline values of both serum Ost and ALP were significantly higher in postmenopausal patients as compared to controls and serum Ost showed a significant reduction after treatment with alendronate compared to those treated with either HRT or Ca and vit. D.From this study we recommend estimating the baseline bone markers (Ost and ALP) status for newly diagnosed osteoporotic patients to be used as a guide for deciding the initial therapeutic intervention, and detection of non responder instead of waiting until patients develop further fracture while they are on therapy. Key words: Osteoporosis, Postmenopause, Osteocalcin, Alendronat

    Multi-objective improvement of software using co-evolution and smart seeding

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    Optimising non-functional properties of software is an important part of the implementation process. One such property is execution time, and compilers target a reduction in execution time using a variety of optimisation techniques. Compiler optimisation is not always able to produce semantically equivalent alternatives that improve execution times, even if such alternatives are known to exist. Often, this is due to the local nature of such optimisations. In this paper we present a novel framework for optimising existing software using a hybrid of evolutionary optimisation techniques. Given as input the implementation of a program or function, we use Genetic Programming to evolve a new semantically equivalent version, optimised to reduce execution time subject to a given probability distribution of inputs. We employ a co-evolved population of test cases to encourage the preservation of the program’s semantics, and exploit the original program through seeding of the population in order to focus the search. We carry out experiments to identify the important factors in maximising efficiency gains. Although in this work we have optimised execution time, other non-functional criteria could be optimised in a similar manner

    Short-term psychodynamic psychotherapy for functional somatic disorders: a systematic review and meta-analysis of within-treatment effects

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    OBJECTIVE: A recent meta-analysis of 17 randomized, controlled trials (RCTs) showed that Short-term Psychodynamic Psychotherapy (STPP) for functional somatic disorders (FSD) reduced somatic symptoms compared to wait list, minimal treatment, and treatment-as-usual controls. A clinically important yet unanswered question is how much improvement patients experience within STPP treatment. METHODS: Following a systematic search, we identified STPP trials presenting data at baseline and post-treatment/follow-up. Meta-analyses determined the magnitude of changes in somatic symptoms and other outcomes from before to after STPP, and analyses examined effect sizes as a function of study, therapy, and patient variables. RESULTS: We identified 37 trials (22 pre-post studies and 15 RCTs) totaling 2094 patients treated an average of 13.34 sessions for a range of FSD. Across all studies, somatic symptoms improved significantly from pre-treatment to short-term follow-up with a large effect size (SMD = −1.07), which was maintained at long-term follow-up (SMD = −0.90). After excluding two outlier studies, effects at short- and medium-term follow-up remained significant but were somewhat reduced in magnitude (e.g., short-term SMD = −0.73). Secondary outcomes including anxiety, depression, disability, and interpersonal problems had medium to large effects. Effects were larger for studies of STPP that were longer than 12 sessions or used an emotion-focused type of STPP, and for chronic pain or gastrointestinal conditions than for functional neurological disorders. CONCLUSIONS: STPP results in moderate to large improvements in multiple outcome domains that are sustained in long-term follow-up. STPP is an effective treatment option for FSD and should be included in treatment guidelines
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