901 resultados para Test-taking skills


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Conformance testing focuses on checking whether an implementation. under test (IUT) behaves according to its specification. Typically, testers are interested it? performing targeted tests that exercise certain features of the IUT This intention is formalized as a test purpose. The tester needs a "strategy" to reach the goal specified by the test purpose. Also, for a particular test case, the strategy should tell the tester whether the IUT has passed, failed. or deviated front the test purpose. In [8] Jeron and Morel show how to compute, for a given finite state machine specification and a test purpose automaton, a complete test graph (CTG) which represents all test strategies. In this paper; we consider the case when the specification is a hierarchical state machine and show how to compute a hierarchical CTG which preserves the hierarchical structure of the specification. We also propose an algorithm for an online test oracle which avoids a space overhead associated with the CTG.

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This paper is concerned with using the bootstrap to obtain improved critical values for the error correction model (ECM) cointegration test in dynamic models. In the paper we investigate the effects of dynamic specification on the size and power of the ECM cointegration test with bootstrap critical values. The results from a Monte Carlo study show that the size of the bootstrap ECM cointegration test is close to the nominal significance level. We find that overspecification of the lag length results in a loss of power. Underspecification of the lag length results in size distortion. The performance of the bootstrap ECM cointegration test deteriorates if the correct lag length is not used in the ECM. The bootstrap ECM cointegration test is therefore not robust to model misspecification.

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The triangular space between memory, narrative and pictorial representation is the terrain on which this article is developed. Taking the art of memory developed by Giordano Bruno (1548 – 1600) and the art of painting subtly revolutionised by Adam Elsheimer (1578 – 1610) as test-cases, it is shown how both subvert the norms of mimesis and narration prevalent throughout the Renaissance, how disrupted memory creates “incoherent” narratives, and how perspective and the notion of “place” are questioned in a corollary way. Two paintings by Elsheimer are analysed and shown to include, in spite of their supposed “realism”, numerous incoherencies, aporias and strange elements – often overlooked. Thus, they do not conform to two of the basic rules governing both the classical art of memory and the humanist art of painting: well-defined places and the exhaustive translatability of words into images (and vice-versa). In the work of Bruno, both his philosophical claims and the literary devices he uses are analysed as hints for a similar (and contemporaneous) undermining of conventions about the transparency and immediacy of representation.

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High-precision measurement of the electrical resistance of nickel along its critical line, a first attempt of this kind, as a function of pressure to 47.5 kbar is reported. Our analysis yields the values of the critical exponents α=α’=-0.115±0.005 and the amplitude ratios ‖A/A’‖=1.17±0.07 and ‖D/D’‖=1.2±0.1. These values are in close agreement with those predicted by renormalization-group (RG) theory. Moreover, this investigation provides an unambiguous experimental verification to one of the key consequences of RG theory that the critical exponents and amplitudes ratios are insensitive to pressure variation in nickel, a Heisenberg ferromagnet.

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The displacement between the ridges situated outside the filleted test section of an axially loaded unnotched specimen is computed from the axial load and shape of the specimen and compared with extensometer deflection data obtained from experiments. The effect of prestrain on the extensometer deflection versus specimen strain curve has been studied experimentally and analytically. An analytical study shows that an increase in the slope of the stress-strain curve in the inelastic region increases the slope of the corresponding computed extensometer deflection versus specimen strain curve. A mathematical model has been developed which uses a modified length ¯ℓef in place of the actual length of the uniform diameter test section of the specimen. This model predicts the extensometer deflection within 5% of the corresponding experimental value. This method has been successfully used by the authors to evolve an iterative procedure for predicting the cyclic specimen strain in axial fatigue tests on unnotched specimens.

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The designing of effective intervention tools to improve immigrants’ labor market integration remains an important topic in contemporary Western societies. This study examines whether and how a new intervention tool, Working Life Certificate (WLC), helps unemployed immigrants to find employment and strengthen their belief of their vocational skills. The study is based on quantitative longitudinal survey data from 174 unemployed immigrants of various origins who participated in the pilot phase of WLC examinations in 2009. Surveys were administered in three waves: before the test, right after it, and three months later. Although it is often argued that the unemployment among immigrants is due either to their lack of skills and cultural differences or to discrimination in recruitment, scholars within social psychology of behavior change argue that the best way of helping people to achieve their goals (e.g. finding employment) is to build up their sense of self-efficacy, alter their outcome expectances in a more positive direction or to help them to construct more detailed action and coping plans. This study aims to shed light on the role of these concepts in immigrants’ labor market integration. The results support the theories of behavior change moderately. Having positive expectances regarding the outcomes of various job search behaviors was found to predict employment in the future. Together with action and coping planning it also predicted increase in job search behavior. The intervention, WLC, was able to affect participants’ self-efficacy, but contrary to expectations, self-efficacy was found not to be related to either job search behavior or future labor market status. Also, perceived discrimination did not explain problems in finding employment, but hints of subtle or structural discrimination were found. Adoption of Finnish work culture together with strong family culture was found to predict future employment. Hence, in this thesis I argue that awarding people diplomas should be preferred in immigrant integration training as it strengthens people’s sense of self-efficacy. Instead of teaching new information, more attention should be directed at changing people’s outcome expectances in a more positive direction and helping them to construct detailed plans on how to achieve their goals.

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Vegetation maps and bioclimatic zone classifications communicate the vegetation of an area and are used to explain how the environment regulates the occurrence of plants on large scales. Many practises and methods for dividing the world’s vegetation into smaller entities have been presented. Climatic parameters, floristic characteristics, or edaphic features have been relied upon as decisive factors, and plant species have been used as indicators for vegetation types or zones. Systems depicting vegetation patterns that mainly reflect climatic variation are termed ‘bioclimatic’ vegetation maps. Based on these it has been judged logical to deduce that plants moved between corresponding bioclimatic areas should thrive in the target location, whereas plants moved from a different zone should languish. This principle is routinely applied in forestry and horticulture but actual tests of the validity of bioclimatic maps in this sense seem scanty. In this study I tested the Finnish bioclimatic vegetation zone system (BZS). Relying on the plant collection of Helsinki University Botanic Garden’s Kumpula collection, which according to the BZS is situated at the northern limit of the hemiboreal zone, I aimed to test how the plants’ survival depends on their provenance. My expectation was that plants from the hemiboreal or southern boreal zones should do best in Kumpula, whereas plants from more southern and more northern zones should show progressively lower survival probabilities. I estimated probability of survival using collection database information of plant accessions of known wild origin grown in Kumpula since the mid 1990s, and logistic regression models. The total number of accessions I included in the analyses was 494. Because of problems with some accessions I chose to separately analyse a subset of the complete data, which included 379 accessions. I also analysed different growth forms separately in order to identify differences in probability of survival due to different life strategies. In most analyses accessions of temperate and hemiarctic origin showed lower survival probability than those originating from any of the boreal subzones, which among them exhibited rather evenly high probabilities. Exceptionally mild and wet winters during the study period may have killed off hemiarctic plants. Some winters may have been too harsh for temperate accessions. Trees behaved differently: they showed an almost steadily increasing survival probability from temperate to northern boreal origins. Various factors that could not be controlled for may have affected the results, some of which were difficult to interpret. This was the case in particular with herbs, for which the reliability of the analysis suffered because of difficulties in managing their curatorial data. In all, the results gave some support to the BZS, and especially its hierarchical zonation. However, I question the validity of the formulation of the hypothesis I tested since it may not be entirely justified by the BZS, which was designed for intercontinental comparison of vegetation zones, but not specifically for transcontinental provenance trials. I conclude that botanic gardens should pay due attention to information management and curational practices to ensure the widest possible applicability of their plant collections.

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Nowadays any analysis of Russian economy is incomplete without taking into account the phenomenon of oligarchy. Russian oligarchs appeared after the fall of the Soviet Union and are represented by wealthy businessmen who control a huge part of natural resources enterprises and have a big political influence. Oligarchs’ shares in some natural resources industries reach even 70-80%. Their role in Russian economy is big without any doubts, however there has been very little economic analysis done. The aim of this work is to examine Russian oligarchy on micro and macro levels, its role in Russia’s transition and the possible positive and negative outcomes from this phenomenon. For this purpose the work presents two theoretical models. The first part of this thesis work examines the role of oligarchs on micro level, concentrating on the question whether the oligarchs can be more productive owners than other types of owners. To answer the question this part presents a model based on the article “Are oligarchs productive? Theory and evidence” by Y. Gorodnichenko and Y. Grygorenko. It is followed by empirical test based on the works of S. Guriev and A. Rachinsky. The model predicts oligarchs to invest more in the productivity of their enterprises and have higher returns on capital, therefore be more productive owners. According to the empirical test, oligarchs were found to outperform other types of owners, however it is not defined whether the productivity gains offset losses in tax revenue. The second part of the work concentrates on the role of oligarchy on macro level. More precisely, it examines the assumption that the depression after 1998 crises in Russia was caused by the oligarchs’ behavior. This part presents a theoretical model based on the article “A macroeconomic model of Russian transition: The role of oligarchic property rights” by S. Braguinsky and R. Myerson, where the special type of property rights is introduced. After the 1998 crises oligarchs started to invest all their resources abroad to protect themselves from political risks, which resulted in the long depression phase. The macroeconomic model shows, that better protection of property rights (smaller political risk) or/and higher outside investing could reduce the depression. Taking into account this result, the government policy can change the oligarchs’ behavior to be more beneficial for the Russian economy and make the transition faster.

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Purpose - This paper aims to validate a comprehensive aeroelastic analysis for a helicopter rotor with the higher harmonic control aeroacoustic rotor test (HART-II) wind tunnel test data. Design/methodology/approach - Aeroelastic analysis of helicopter rotor with elastic blades based on finite element method in space and time and capable of considering higher harmonic control inputs is carried out. Moderate deflection and coriolis nonlinearities are included in the analysis. The rotor aerodynamics are represented using free wake and unsteady aerodynamic models. Findings - Good correlation between analysis and HART-II wind tunnel test data is obtained for blade natural frequencies across a range of rotating speeds. The basic physics of the blade mode shapes are also well captured. In particular, the fundamental flap, lag and torsion modes compare very well. The blade response compares well with HART-II result and other high-fidelity aeroelastic code predictions for flap and torsion mode. For the lead-lag response, the present analysis prediction is somewhat better than other aeroelastic analyses. Research limitations/implications - Predicted blade response trend with higher harmonic pitch control agreed well with the wind tunnel test data, but usually contained a constant offset in the mean values of lead-lag and elastic torsion response. Improvements in the modeling of the aerodynamic environment around the rotor can help reduce this gap between the experimental and numerical results. Practical implications - Correlation of predicted aeroelastic response with wind tunnel test data is a vital step towards validating any helicopter aeroelastic analysis. Such efforts lend confidence in using the numerical analysis to understand the actual physical behavior of the helicopter system. Also, validated numerical analyses can take the place of time-consuming and expensive wind tunnel tests during the initial stage of the design process. Originality/value - While the basic physics appears to be well captured by the aeroelastic analysis, there is need for improvement in the aerodynamic modeling which appears to be the source of the gap between numerical predictions and HART-II wind tunnel experiments.

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A method has been suggested to accurately determine the DBTT of diffusion aluminide bond coats. Micro-tensile testing of free-standing coating samples has been carried out. The DBTT was determined based on the variation of plastic strain-to-fracture with temperature. The positive features of this method over the previously reported techniques are highlighted. (C) 2010 Elsevier B.V. All rights reserved.

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Conventional Random access scan (RAS) for testing has lower test application time, low power dissipation, and low test data volume compared to standard serial scan chain based design In this paper, we present two cluster based techniques, namely, Serial Input Random Access Scan and Variable Word Length Random Access Scan to reduce test application time even further by exploiting the parallelism among the clusters and performing write operations on multiple bits Experimental results on benchmarks circuits show on an average 2-3 times speed up in test write time and average 60% reduction in write test data volume

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The purpose of the research was to determine how well Finnish children and youngsters in different ages recognize poisonous and eatable wild plant species and to which characteristics they pay attention to when identifying plants. The purpose was also to find out, how well the pupils and students can estimate if the wild plants are either poisonous or eatable. The goal was to gather knowledge about what factors explain these recognition and estimation skills. Also information was wanted about attitudes of children and youngsters towards recognizing and learning the poisonous and eatable wild plants. The research was made on subjects of 48 children and youngsters from grade 6 in primary school, grade 8 in lower- secondary school and vocational school. Both quantitative and qualitative methods were used. A plant recognition test, where 38 pictures on plants was presented, was made for the all subjects. The subjects were requested to name the plants and classify them to be either poisonous or eatable. In addition six students were interviewed from each class, altogether 18 subjects. The themes of the interviews were the attitudes towards eatable and poisonous wild plants and to learn to recognize species. During the interview pictures of plants were looked at and the subjects told which characteristics they pay attention to when trying to recognize it. The results showed that on average wild plants were recognized insufficiently. Standard variation in responses was large in all classes researched. The subjects got better results in classifying of the plants to be either poisonous or eatable than in naming the plants. This research shows that even when a subject cannot name a plant it is still possible for the subject to classify the plant to be either poisonous or eatable. Gender and being an immigrant explained the recognition skills of poisonous and eatable plants so that girls were somewhat better to recognize plant species and native Finns recognized poisonous and eatable plants better that immigrants. Age did not explain the skills to recognize species directly, since students in lower- secondary school recognized the poisonous and eatable plants better than primary school and vocational school students. In skills to estimate plants poisonous or eatability there was no difference according to gender, age, or immigrant background. The subjects considered the skills to recognize poisonous and eatable plants important. Learning to recognize plants at school was not considered interesting however. Since the recognition of plants in neighborhood belongs to tasks of general education it is important to think about how the teaching could be made interesting. According to findings of this study, especially the recognition of poisonous plants was considered important by the subjects. This knowledge as well as teaching about possibilities to utilize plants could be used as a way to motivate and teach the students. Avainsanat Nyckelord - Keywords Plant species recognition, recognition of poisonous plants, recognition of eatable plants, plant species education

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Vapor-liquid equilibrium data have been measured for the binary systems methyl ethyl ketone-p-xylene and chlorobenzene-p-xylene, at 685 mmHg pressure. The activity coefficients have been evaluated taking Into consideration the vapor-phase nonideallty. The f-x-y data have been subjected to a thermodynamic consistency test and the activity coefficients have been correlated by the Wilson equation.