A survey of adaptive control technology in robotics

Previous work on the adaptive control of robotic systems is reviewed. Although the field is relatively new and does not yet represent a mature discipline, considerable attention has been given to the design of sophisticated robot controllers. Here, adaptive control methods are divided into model reference adaptive systems and self-tuning regulators with further definition of various approaches given in each class. The similarity and distinct features of the designed controllers are delineated and tabulated to enhance comparative review

The evolution of the Aristolochia pallida complex (Aristolochiaceae) challenges traditional taxonomy and reflects large-scale glacial refugia in the Mediterranean

The taxonomy of the Mediterranean Aristolochia pallida complex has been under debate since several decades with the following species currently recognized: A. pallida, A. lutea, A. nardiana, A. microstoma, A. merxmuelleri, A. croatica, and A. castellana. These taxa are distributed from Iberia to Turkey. To reconstruct phylogenetic and biogeographic patterns, we employed cpDNA sequence variation using both noncoding (intron and spacer) and protein-coding regions (i.e., trnK intron, matK gene, and trnK-psbA spacer). Our results show that the morphology-based traditional taxonomy was not corroborated by our phylogenetic analyses. Aristolochia pallida, A. lutea, A. nardiana, and A. microstoma were not monophyletic. Instead, strong geographic signals were detected. Two major clades, one exclusively occurring in Greece and a second one of pan-Mediterranean distribution, were found. Several subclades distributed in Greece, NW Turkey, Italy, as well as amphi-Adriatic subclades, and a subgroup of southern France and Spain, were revealed. The distribution areas of these groups are in close vicinity to hypothesized glacial refugia areas in the Mediterranean. According to molecular clock analyses the diversification of this complex started around 3–3.3 my, before the onset of glaciation cycles, and the further evolution of and within major lineages falls into the Pleistocene. Based on these data, we conclude that the Aristolochia pallida alliance survived in different Mediterranean refugia rarely with low, but often with a high potential for range extension, and a high degree of morphological diversity.Turkish Science Foundatio

Copula-based probabilistic assessment of intensity and duration of cold episodes: A case study of Malayer vineyard region

Frost, particularly during the spring, is one of the most damaging weather phenomena for vineyards, causing significant economic losses to vineyards around the world each year. The risk of tardive frost damage in vine-yards due to changing climate is considered as an important threat to the sustainable production of grapes. Therefore, the cold monitoring strategies is one of the criteria with significant impacts on the yields and prosperity of horticulture and raisin factories. Frost events can be characterized by duration and severity. This paper investigates the risk and impacts of frost phenomenon in the vineyards by modeling the joint distribution of duration and severity factors and analyzing the influential parameter’s dependency structure using capabilities of copula functions. A novel mathematical framework is developed within this study to understand the risk and uncertainties associate with frost events and the impacts on yields of vineyards by analyzing the non-linear dependency structure using copula functions as an efficient tool. The developed model was successfully vali-dated for the case study of vineyard in Malayer city of Iran. The copula model developed in this study was shown to be a robust tool for predicting the return period of the frost events

International collaborative follow - up investigation of graduating high school students’ understandings of the nature of scientific inquiry: is progress Being made?

Understandings of the nature of scientific inquiry (NOSI), as opposed to engaging students in inquiry learning experiences, are included in science education reform documents around the world. However, little is known about what students have learned about NOSI during their pre-college school years. The purpose of this large-scale follow-up international project (i.e. 32 countries and regions, spanning six continents and including 3917 students for the high school sample) was to collect data on what exiting high school students have learned about NOSI. Additionally, the study investigated changes in 12th grade students’ NOSI understandings compared to seventh grade (i.e. 20 countries and regions) students’ understandings from a prior investigation [Lederman et al. (2019). An international collaborative investigation of beginning seventh grade students’ understandings of scientific inquiry: Establishing a baseline. Journal of Research in Science Teaching, 56(4), 486–515. https://doi.org/10.1002/tea.21512]. This study documents and discusses graduating high school students’ understandings and compares their understandings to seventh grade students’ understandings of the same aspects of scientific inquiry for each country. It is important to note that collecting data from each of the 130+ countries globally was not feasible. Similarly, it was not possible to collect data from every region of each country. A concerted effort was made, however, to provide a relatively representative picture of each country and the world

DETERMINATION OF BACLOFEN IN HUMAN PLASMA AND URINE BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH FLUORESCENCE DETECTION

An isocratic reversed-phase column liquid chromatographic assay for baclofen was developed. Prior to analysis, derivatization of urine or deproteinized plasma with 4-chloro-7-nitrobenzofurazan (NBD-CI) reagent was employed. After solid-phase extraction on a small silica gel column, the mixture was chromatographed on a 10 mu m Bondapak C-18 column using methanol-water (45 + 55 v/v) as the mobile phase, The NBD-baclofen derivative was detected spectrofluorimetrically by monitoring the emission at 524 nm with excitation at 463 nm. The method was tested for suitability in routine analysis. After a single oral dose of 20 mg of baclofen, the plasma concentration and the cumulative urinary excretion of the drug were determined. The average recoveries were 99.5 and 98.5% for plasma and urine, respectively

Spectrophotometric determination of mexiletine hydrochloride in capsules using bromothymol blue

A new spectrophotometric method based on the formation of an ion-pair using bromothymol blue as ion-pair complexing reagent was developed for the determination of mexiletine hydrochloride in capsules. The ion-pair formed was highly coloured and easily extracted with dichloromethane. The calibration curve was linear over the concentration range 1.08-10.8 mug.ml(-1) at lambda(max) = 408 nm (r = 0.9999). The results obtained from the developed method were compared statistically with those obtained by the British Pharmacopeia, method

Learning with computers: experiences of evaluation

At the Open University (OU), the perception of computer assisted learning (CAL) is shifting from its current position as an optional extra in a battery of course components to that of a key teaching medium. This paper presents the authors' experiences of the evaluation of a range of current OU produced computer assisted learning materials, mainly but not exclusively in science and technology reported in terms of evaluation framework. These materials include interactive tutorial packages, simulations used largely in a support role to the main teaching and multimedia packages which are expected to carry more of the initial presentation of key ideas in the courses. The overall purpose of the evaluations was to gain insight into how computers can have an impact on learning, particularly of science and technology subjects, and to explore a portfolio of evaluation techniques to be used in the development and assessment of computer based learning materials. In this paper the techniques are discussed and illustrated with reference to a number of case studies of a range of programs used by students. Some conclusions are drawn about how the use of programs leads to the support of students' science and technology learning

Feeding biology in Bufo viridis (Anura: Bufonidae) populations of the vicinity of İzmir [İzmir çevresi Bufo viridis (Anura: Bufonidae) populasyonlarinda beslenme biyolojisi]

In this study, the feeding biology is being examined on 80 Bufo viridis specimens (30 > > , 50 + +) which were all collected from 6 localities of the vicinity of İzmir. In accordance with the stomach content analysis it was fully determined that the species is predominantly nourished in a insectivorous way (92, 20%) and also Oligochaeta, Crustacea, Arachnida, Gastropoda, Diplopoda, Chilopoda and Amphibia take place in its nutrition types. Throught out the insects, Hymenoptera, Coleoptera, Diptera, Hemiptera, Dermaptera, Homoptera, Plecoptera, Blattaria and Embioptera; from Oligochaeta Lumbriculida; from Crustacea lsopoda; from Arachnida Araneae and Opiliones; from Gastropoda Stylommatophora; from Diplopoda Julida; from Chilopoda Lithobiida and Scolopendrida and also from Amphibia only Anur genus were being determined

Growth characteristics and reproduction of comber, Serranus cabrilla (Actinopterygii, Perciformes, Serranidae), in the Aegean Sea

Background. Even thoughSerranus cabrilla has been aby-catch species in trawling operations, it is now becoming an economically important fish species on the Turkish Coast of Aegean Sea, because of its low market price. For an efficient fisheries management of the stocks it is important to know important biological parameters of the commercially exploited species. Therefore the aim of this study was to obtain necessary growth- and reproductive characteristics of comber representing the local population of this fish in the study area. Materials and methods. Biological aspects of comber were examined based on a total of 1452 specimens collected from the Aegean Sea, during the period January 2005–December 2005.Age of fish was determined by otolith reading. Length–weight relation and the von Bertalanffy equationwere used to evaluate the fish growth. Results. Annuli on otoliths indicated the presence of 6 age classes. The computed growth parameters were: L∞ = 23.88 cm; k = 0.298 year–1 and to = –1.577 year. The length–weight relations were calculated as: W= 0.0111· L2.998 for sex combined. The growth performance index (Φ′) was 2.230. The fish mature sexually for the first time at a total length of 13.20 cm (L50). The spawning season of comber was from March to May, with a peak in April. Conclusion. The comber grows rapidly attaining almost 75% of its linear growth during the first two years of life and then the growth slows down. The growth coefficient, (k), indicates slow attainment of maximum size because of significantly correlated to temperature of sea water, leading to a considerable variability in the life span between areas