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3242. Composite control of the n-link chained mechanical systems
- Creator:
- Zikmund, Jiří
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- nonlinear systems, exact linearization, and underactuated mechanical systems
- Language:
- English
- Description:
- In this paper, a new control concept for a class of underactuated mechanical system is introduced. Namely, the class of n-link chains, composed of rigid links, non actuated at the pivot point is considered. Underactuated mechanical systems are those having less actuators than degrees of freedom and thereby requiring more sophisticated nonlinear control methods. This class of systems includes among others frequently used for the modeling of walking planar structures. This paper presents the stabilization of the underactuated n-link chain systems with a wide basin of attraction. The equilibrium point to be stabilized is the upright inverted and unstable position. The basic methodology of the proposed approach consists of various types of partial exact linearization of the model. Based on a suitable exact linearization combined with the so-called "composite principle", the asymptotic stabilization of several underactuated systems is achieved, including a general n-link. The composite principle used herein is a novel idea combining certain fast and slow feedbacks in different coordinate systems to compensate the above mentioned lack of actuation. Numerous experimental simulation results have been achieved confirming the success of the above design strategy. A proof of stability supports the presented approach.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3243. Composition operators on Musielak-Orlicz spaces of Bochner type
- Creator:
- Raj, Kuldip and Sharma, Sunil K.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Orlicz space, Musielak-Orlicz space, Musielak-Orlicz space of Bochner type, composition operator, invertible operator, compact operator, closed range, and isometry and Fredholm operator
- Language:
- English
- Description:
- The invertible, closed range, compact, Fredholm and isometric composition operators on Musielak-Orlicz spaces of Bochner type are characterized in the paper.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3244. Composition technique in Dhūmil´s poetry
- Creator:
- Offredi, Mariola
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- poetry
- Language:
- English
- Description:
- This paper deals with composition technique in the poetry of Dhūmil (Sudāmā Pāṇḍey “Dhūmil”, 1936-1975). While the poet is capable of producing “attractive” images, as may be seen in some unpublished fragments of his earliest work, in the poems in the collection Sansad se saṛak tak (From Parliament to the Street, 1972, 2nd edn. 1975), he uses a “visionary” or hallucinatory method to create provocative images. This provocative vein runs through the entire collection, as one image does not slide seamlessly to the next as it does in Muktibodh’s poetry
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3245. Composition-diamond lemma for modules
- Creator:
- Chen, Yuqun, Chen, Yongshan, and Zhong, Chanyan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Gröbner-Shirshov basis, module, Lie algebra, Kac-Moody algebra, conformal algebra, and Sabinin algebra
- Language:
- English
- Description:
- We investigate the relationship between the Gröbner-Shirshov bases in free associative algebras, free left modules and "double-free" left modules (that is, free modules over a free algebra). We first give Chibrikov's Composition-Diamond lemma for modules and then we show that Kang-Lee's Composition-Diamond lemma follows from it. We give the Gröbner-Shirshov bases for the following modules: the highest weight module over a Lie algebra $sl_2$, the Verma module over a Kac-Moody algebra, the Verma module over the Lie algebra of coefficients of a free conformal algebra, and a universal enveloping module for a Sabinin algebra. As applications, we also obtain linear bases for the above modules.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3246. Compound geometric and Poisson models
- Creator:
- Hakamipour, Nooshin, Rezaei, Sadegh, and Nadarajah, Saralees
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- exponential distribution, exponentiated exponential distribution, and maximum likehood estimation
- Language:
- English
- Description:
- Many lifetime distributions are motivated only by mathematical interest. Here, eight new families of distributions are introduced. These distributions are motivated as models for the stress of a system consisting of components working in parallel/series and each component has a fixed number of sub-components working in parallel/series. Mathematical properties and estimation procedures are derived for one of the families of distributions. A real data application shows superior performance of a three-parameter distribution (performance assessed with respect to Kolmogorov-Smirnov statistics, AIC values, BIC values, CAIC values, AICc values, HQC values, probability-probability plots, quantile-quantile plots and density plots) versus thirty one other distributions, each having at least three parameters.\\
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3247. Comprehensive analysis of PTEN in primary cutaneous melanoma
- Creator:
- Němejcová, K., Dundr, P., Jakša, R. , Bártů, M. , Stružinská, I., Hojný, J. , Hájková, N., and Kodet, O.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- melanoma, mutation, deletion, loss of expression, and PTEN
- Language:
- English
- Description:
- Phosphatase and tensin homologue (PTEN) is a tumour suppressor gene implicated in tumorigenesis of melanoma, with distinct cytoplasmic and nuclear functions. Cytoplasmic PTEN negatively regulates the PI3K/AKT/mTOR signalling pathway, while nuclear PTEN works as a tumour suppressor. Clinical data suggest that the loss of PTEN function in melanoma is associated with aggressive tumour behaviour. We performed a comprehensive analysis of PTEN in 112 primary cutaneous melanomas including immunohistochemical (IHC), fluorescent in situ hybridization (FISH), next-generation sequencing (NGS), and epigenetic analysis. The goal of our study was to: (a) correlate PTEN expression with selected clinico-pathological variables, and assess its prognostic significance; (b) correlate molecular aberrations with PTEN expression to consider the utility of immunohistochemical analysis of PTEN protein expression for screening PTEN genetic alterations; (c) review the literature and evaluate the PTEN expression level in melanoma with respect to possible therapeutic targeting. Our results showed that PTEN molecular alterations were present in 4/20 (20 %) cases with a loss of expression, 3/11 (27 %) cases with clonal-like expression, and 1/81 (1 %) cases with positive PTEN expression. No PTEN promoter methylation was found in any of the cases. Even though the value of our observation is limited by the low number of cases fully evaluated by IHC (112 cases), FISH (19 cases) and NGS (30 cases), our data suggest that IHC is not an appropriate method for the screening of PTEN genetic alterations. Our survival analysis suggests that patients with positive cytoplasmic PTEN expression show better disease-free survival (P < 0.05).
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3248. Comprehensive assessment of positioning and zenith total delay retrieval using GPS+GLONASS precise point positioning
- Creator:
- Zhou, Feng, Gu, Shengfeng, Chen, Wen, and Dong, Danan
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, GPS sítě, GPS netwoks, GLONASS, precise point positioning (PPP), zenith total delay (ZTD), antenna/radome-dependent biases, 7, and 551
- Language:
- English
- Description:
- Since October 2011, the Russian GLObal NAvigation Satellite System (GLONASS) has been revitalized and is now fully operational with 24 satellites in orbit. It is critical to assess the benefits and problems of using GLONASS observations (i.e. GLONASS-only or combined Global Positioning System (GPS) and GLONASS) for precise positioning and zenith total delay (ZTD) retrieval on a global scale using precise point positioning (PPP) technique. In this contribution, extensive evaluations are conducted with Global Navigation Satellite System (GNSS) data sets collected from 251 globally distributed stations of the International GNSS Service (IGS) network in July 2016. The stations are divided into 30 groups by antenna/radome types to investigate whether there are ante nna/radome-dependent biases in position and ZTD derived from GLONASS-only PPP. The positioning results do not show obvious antenna/radome-dependent biases except the stations with JAV_RINGANT_G3T/NONE. For these stations, the averaged biases in horizontal component, especially in the north component, can achieve as high as -9.0 mm. The standard de viation (STD) and root mean square (RMS) are used as indicators of positioning repeatability and accuracy, respectively. The averaged horizontal STD and RMS of GLONASS-only PPP are comparable to GPS-only PPP, while in vertical component, those for GLONASS-only P PP are larger. Furthermore, the STD and RMS of GPS+GLONASS combined PPP solutions are the smallest in horizontal and vertical components, indicating that adding GLONASS observations can achieve better positioning performance than GPS-only PPP. With the IGS final ZTD as reference, we find that ZTD biases and accuracy of GLONASS-only are latitude - and antenna/radome-independent. The ZTD accuracy of GLONASS-only PPP is slightly worse than that of GPS-only PPP. Compared with GPS-only PPP, the ZTD accuracy is only improved by 1.3% from 7.8 to 7.7 mm by adding GLONASS observations., Feng Zhou, Shengfeng Gu, Wen Chen and Danan Dong., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3249. Comprehensive treatment for brain meningiomas and their recurrences using proton therapy
- Creator:
- Alimov, Jamshidjon and Alimov, Rustamjon
- Format:
- braille, electronic resource, remote, and elektronický zdroj
- Type:
- model:article, article, Text, statistics, kazuistiky, and TEXT
- Subject:
- protony--terapeutické užití, meningeom--radioterapie, nádory mozku--radioterapie, výsledek terapie, dávkování radioterapie, ženské pohlaví, lidé, and lidé středního věku
- Language:
- English
- Description:
- This article presents results of using proton therapy after operation of patient with brain meningioma. After operation brain meningiomas is known to not rarely recur due to certain localization and growth of tumor into main cerebral vessels, nerves and other main brain structures. This creates certain difficulties in operative access and surgical intervention, i.e. tumor resection. Proton therapy sharply reduces complications and improves the quality of life of patients., Jamshidjon Alimov, Rustamjon Alimov, and Literatura
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3250. Comptes rendus publiés par le comité national d'organisation: VIII. conférence internationale de psychotechnique, tenue á Prague du 11 au 15 septembre 1934 sous la présidence du F. Šeracký
- Creator:
- František Šeracký
- Publisher:
- Orbis
- Format:
- print and 863 s. : il., tab.
- Type:
- text, volume, výzkumné zprávy, sborníky konferencí, model:monograph, and TEXT
- Subject:
- Výchova a vzdělávání, Psychologie, pedagogický výzkum, žáci, duševní schopnosti, výchova a vzdělávání, mezinárodní konference, Evropa, 37.012, 159.928, (4), (063), 22, 17, 37, and 159.9
- Language:
- French, English, and German
- Description:
- F. Šeracký., KČSN, and Část. anglický a německý text
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public