1,585 research outputs found
Методический аппарат когнитивного моделирования социально-экономической системы (университета)
Purpose of the study. The aim of the study is to improve the methodological apparatus of cognitive modeling of socio-economic systems (SES) and predicting the indicators of their functioning and development, which ensures an increase in the accuracy and reliability of the results obtained. Existing models and methods do not fully provide the necessary accuracy and reliability of models that requires the development of the mathematical apparatus of cognitive modeling in terms of improving the quality of the developed cognitive models.Materials and methods. To achieve this goal, methods of an integrated approach to solving the problem, decomposing it into interrelated stages, describing the content of each stage in their relationship and presenting a generalized version of the methodology, taking into account the characteristics of the object of study, were used. The developed approach provides creating a more accurate and reliable cognitive model. The effectiveness of the developed methodological apparatus is shown.Results. A detailed analysis of the existing criteria and approaches to solving the problem of verification of cognitive models was carried out, which showed the absence of a unified methodology and an integrated approach in solving problems of cognitive modeling of SES based on cognitive maps. A set of techniques that implement the stages of cognitive modeling has been developed. The results of a comparative analysis of the developed approach with the existing ones are presented.Conclusion. A comprehensive solution to the problem of creating a cognitive model for analyzing and predicting the activities of a university is proposed, which includes a set of stages: the stage of creating the problem field of the situation; identification of factors and relationships between them; the stage of making a cognitive map and its verification, as well as the stage of analyzing the system characteristics of the cognitive model, validating the cognitive model. The developed methodological apparatus includes a set of techniques aimed at obtaining an adequate model that provides more accurate and reliable results of modeling the object of study.Цель исследования. Целью исследования является совершенствование методического аппарата когнитивного моделирования социально-экономических систем (СЭС) и прогнозирования показателей их функционирования и развития, обеспечивающего повышение точности и достоверности получаемых результатов. Существующие модели и методики не в полной мере обеспечивают необходимую точность и достоверность моделей, что требует развития математического аппарата когнитивного моделирования в части повышения качества разрабатываемых когнитивных моделей.Материалы и методы. Для достижения поставленной цели использованы методы комплексного подхода к решению поставленной задачи, декомпозиции ее на взаимосвязанные этапы, описание содержания каждого этапа в их взаимосвязи и представление обобщенного варианта методики с учетом особенностей объекта исследования. Разработанный подход обеспечивает построение более точной и достоверной когнитивной модели. Показана эффективность разработанного методического аппарата.Результаты. Проведен детальный анализ существующих критериев и подходов к решению задачи верификации когнитивных моделей, который показал отсутствие единой методики и комплексного подхода в решении задач когнитивного моделирования СЭС на основе когнитивных карт. Разработана совокупность методик, реализующих этапы когнитивного моделирования: методика построения проблемного поля ситуации; методика синтеза когнитивной карты, ее структурно-целевого анализа и анализа системных характеристик, а также методика верификации когнитивной модели.Заключение. Предложено комплексное решение задачи построения когнитивной модели анализа и прогнозирования деятельности университета, включающее совокупность этапов: этап построения проблемного поля ситуации; идентификации факторов и связей между ними; этапе построения когнитивной карты и ее верификации, а также этап анализа системных характеристик когнитивной модели, валидации когнитивной модели. Разработанный методический аппарат предназначен для получения адекватной модели, обеспечивающей более точные и достоверные результаты моделирования объекта исследования
Bose-Einstein correlations of same-sign charged pions in the forward region in pp collisions at √s=7 TeV
Bose-Einstein correlations of same-sign charged pions, produced in protonproton collisions at a 7 TeV centre-of-mass energy, are studied using a data sample collected
by the LHCb experiment. The signature for Bose-Einstein correlations is observed in the
form of an enhancement of pairs of like-sign charged pions with small four-momentum
difference squared. The charged-particle multiplicity dependence of the Bose-Einstein correlation parameters describing the correlation strength and the size of the emitting source
is investigated, determining both the correlation radius and the chaoticity parameter. The
measured correlation radius is found to increase as a function of increasing charged-particle
multiplicity, while the chaoticity parameter is seen to decreas
Evaluation of myocardial damage in different types of rheumatoid arthritisduring disease-modifying antirheumatic drug or biological therapy (with infliximab)
Objective. To estimate the extent and pattern of myocardial damage in different types of rheumatoid arthritis (RA) during disease-modifying antirheumatic drug (DMARD) or biological therapy. Subjects and methods. Seventy-one patients with RA were examined; some of them received biological therapy with infliximab, while the others took DMARDs. A group of patients with incipient RA was also identified. B-type brain natriuretic peptide levels were estimated and electrocardiography, echocardiography (EchoCG), and cardiac magnetic resonance imaging (MRT) using the contrast medium Dotarem were conducted in all the patients. The follow-up totaled 6 months. A control examination was made at the moment of randomization and 6 months posttreatment. Results. Tn the bulk of patients, the level of B-type brain natriuretic peptide did not differ from the reference values, however, its lower level was observed in the incipient RA group, which was associated with the absence of cardiovascular diseases and with a younger age group. There were no negative EchoCG changes in myocardial viability values. Cardiac MRT demonstrated that the majority of patients had the similar changes that failed to affect myocardial kinetics and ejection fraction. These changes were not found in incipient RA patients without cardiovascular diseases. No improvement in myocardial viability was recorded in the patients receiving the biological therapy. Conclusion. Thus, cardiac MRT showed the similar changes that failed to affect myocardial kinetics and ejection fraction in patients with RA during both methotrexate and infliximab therapy
Measurement of the lifetime
Using a data set corresponding to an integrated luminosity of ,
collected by the LHCb experiment in collisions at centre-of-mass energies
of 7 and 8 TeV, the effective lifetime in the
decay mode, , is measured to be ps. Assuming
conservation, corresponds to the lifetime of the light
mass eigenstate. This is the first measurement of the effective
lifetime in this decay mode.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-017.htm
Observation of two new baryon resonances
Two structures are observed close to the kinematic threshold in the mass spectrum in a sample of proton-proton collision data, corresponding
to an integrated luminosity of 3.0 fb recorded by the LHCb experiment.
In the quark model, two baryonic resonances with quark content are
expected in this mass region: the spin-parity and
states, denoted and .
Interpreting the structures as these resonances, we measure the mass
differences and the width of the heavier state to be
MeV,
MeV,
MeV, where the first and second
uncertainties are statistical and systematic, respectively. The width of the
lighter state is consistent with zero, and we place an upper limit of
MeV at 95% confidence level. Relative
production rates of these states are also reported.Comment: 17 pages, 2 figure
Differential branching fraction and angular analysis of the decay B0→K∗0μ+μ−
The angular distribution and differential branching fraction of the decay B 0→ K ∗0 μ + μ − are studied using a data sample, collected by the LHCb experiment in pp collisions at s√=7 TeV, corresponding to an integrated luminosity of 1.0 fb−1. Several angular observables are measured in bins of the dimuon invariant mass squared, q 2. A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be q20=4.9±0.9GeV2/c4 , where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions
Study of charmonium production in b -hadron decays and first evidence for the decay Bs0
Using decays to φ-meson pairs, the inclusive production of charmonium states in b-hadron decays is studied with pp collision data corresponding to an integrated luminosity of 3.0 fb−1, collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. Denoting byBC ≡ B(b → C X) × B(C → φφ) the inclusive branching fraction of a b hadron to a charmonium state C that decays into a pair of φ mesons, ratios RC1C2 ≡ BC1 /BC2 are determined as Rχc0ηc(1S) = 0.147 ± 0.023 ± 0.011, Rχc1ηc(1S) =0.073 ± 0.016 ± 0.006, Rχc2ηc(1S) = 0.081 ± 0.013 ± 0.005,Rχc1 χc0 = 0.50 ± 0.11 ± 0.01, Rχc2 χc0 = 0.56 ± 0.10 ± 0.01and Rηc(2S)ηc(1S) = 0.040 ± 0.011 ± 0.004. Here and below the first uncertainties are statistical and the second systematic.Upper limits at 90% confidence level for the inclusive production of X(3872), X(3915) and χc2(2P) states are obtained as RX(3872)χc1 < 0.34, RX(3915)χc0 < 0.12 andRχc2(2P)χc2 < 0.16. Differential cross-sections as a function of transverse momentum are measured for the ηc(1S) andχc states. The branching fraction of the decay B0s → φφφ is measured for the first time, B(B0s → φφφ) = (2.15±0.54±0.28±0.21B)×10−6. Here the third uncertainty is due to the branching fraction of the decay B0s → φφ, which is used for normalization. No evidence for intermediate resonances is seen. A preferentially transverse φ polarization is observed.The measurements allow the determination of the ratio of the branching fractions for the ηc(1S) decays to φφ and p p asB(ηc(1S)→ φφ)/B(ηc(1S)→ p p) = 1.79 ± 0.14 ± 0.32
Study of J /ψ production in Jets
The production of J/ψ mesons in jets is studied in the forward region of proton-proton collisions using data collected with the LHCb detector at a center-of-mass energy of 13 TeV. The fraction of the jet transverse momentum carried by the J/ψ meson, z(J/ψ)≡pT(J/ψ)/pT(jet), is measured using jets with pT(jet)>20 GeV in the pseudorapidity range 2.5<η(jet)<4.0. The observed z(J/ψ)distribution for J/ψ mesons produced in b-hadron decays is consistent with expectations. However, the results for prompt J/ψ production do not agree with predictions based on fixed-order nonrelativistic QCD. This is the first measurement of the pT fraction carried by prompt J/ψ mesons in jets at any experiment
Search for CP violation in D+→ϕπ+ and D+s→K0Sπ+ decays
A search for CP violation in D + → ϕπ + decays is performed using data collected in 2011 by the LHCb experiment corresponding to an integrated luminosity of 1.0 fb−1 at a centre of mass energy of 7 TeV. The CP -violating asymmetry is measured to be (−0.04 ± 0.14 ± 0.14)% for candidates with K − K + mass within 20 MeV/c 2 of the ϕ meson mass. A search for a CP -violating asymmetry that varies across the ϕ mass region of the D + → K − K + π + Dalitz plot is also performed, and no evidence for CP violation is found. In addition, the CP asymmetry in the D+s→K0Sπ+ decay is measured to be (0.61 ± 0.83 ± 0.14)%
Search for hidden-sector bosons in decays
A search is presented for hidden-sector bosons, , produced in the decay
, with and
. The search is performed using -collision data
corresponding to 3.0 fb collected with the LHCb detector. No significant
signal is observed in the accessible mass range
MeV, and upper limits are placed on the branching fraction product
as
a function of the mass and lifetime of the boson. These limits are of
the order of for lifetimes less than 100 ps over most of the
range, and place the most stringent constraints to date on many
theories that predict the existence of additional low-mass bosons.Comment: All figures and tables, along with supplementary material, are
available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-036.htm
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