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Wyświetlanie 1-15 z 118
Tytuł:
On the inverse problems of Lyapunov theorem and Riccati equation
Autorzy:
Sun, Y.
Powiązania:
https://bibliotekanauki.pl/articles/205963.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
teoria systemu liniowego
zagadnienie odwrotne
inverse problems
linear systems theory
Opis:
In this note, the inverse problem of Lyapunov theorem is reconsidered and the inverse problem of Riccati equation is introduced. Simple proofs are provided to guarantee the solution of such problems.
Źródło:
Control and Cybernetics; 2001, 30, 2; 227-230
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rugose corals and brachiopods across the Frasnian-Famennian boundary in Central Hunan, South China
Autorzy:
Ma, X
Sun, Y.
Hao, W.
Liao, W.
Powiązania:
https://bibliotekanauki.pl/articles/21047.pdf
Data publikacji:
2002
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
fossil distribution
brachiopod fauna
brahiopod
Rugosa
China
rugose coral
Ostracoda
Brachiopoda
Famennian
Frasnian
Devonian
extinction
coral
paleontology
Hunan
Opis:
We present taxonomic revision of rugose corals and brachiopods from several Frasnian–Fammenian (F–F) boundary sections in central Hunan Province, China. Diversity of shallow−water rugose corals gradually increased during the Frasnian, but ended with sudden extinction near the end of Frasnian. Ostracods were abundant during the Frasnian; their extinction coincided with anoxic deposition of the end−Frasnian black shale deposits. The early Famennian ostracod fauna is of low diversity. The brachiopod fauna of the late Frasnian (Palmatolepis rhenana and Pa. linguiformis zones) is dominated by atrypids, small−sized cyrtospiriferids, and the rhynchonellid Hunanotoechia. All atrypids disappeared before the F–F boundary with highest rates of extinction below the boundary (probably low in the Pa. linguiformis Zone). The Frasnian cyrtospiriferid fauna is also of low diversity and dominated by small taxa. All but one of the cyrtospiriferid taxa crossed the F–F boundary. The early Famennian post−extinction recovery brachiopod fauna was the result of rapid radiation of new forms shortly after the terminal Frasnian event. The early Famennian fauna is characterized by diverse cyrtospiriferids, abundant Yunnanellina and productoids. Above the early recovery fauna another fauna was recovered, with brachiopods Hunanospirifer and Yunnanella and is correlated with the late or latest Pa. crepida Zone. Sinalosia rugosa gen. et sp. nov. (Productida) is erected.
Źródło:
Acta Palaeontologica Polonica; 2002, 47, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Relationship between the impedance of a multi-pin probe and soil water content
Autorzy:
Sun, Y.
Kromer, K.H.
Powiązania:
https://bibliotekanauki.pl/articles/24149.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
soil water
relationship
dielectrical constant
impedance
multi-pin probe
water content
Źródło:
International Agrophysics; 2003, 17, 1
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The eigenvalue derivatives of linear damped systems
Autorzy:
Sun, Y.-J.
Powiązania:
https://bibliotekanauki.pl/articles/970588.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
pochodna wartości własnej
derivatives of eigenvalues
linear damped systems
Opis:
In this note, the derivatives of eigenvalues with respect to the model parameters for linear damped systems is proposed by means of kronecker algebra and matrix calculus. A numerical example is also provided to illustrate the use of the main result.
Źródło:
Control and Cybernetics; 2003, 32, 4; 735-741
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The kinetics of 1,1-dichloroethene (CCl2=CH2) and trichloroethene (HClC=CCl2) decomposition in dry and humid air under the influence of electron beam
Autorzy:
Nichipor, H.
Dashouk, E.
Yacko, S.
Chmielewski, A.
Zimek, Z.
Sun, Y.
Vitale, S.
Powiązania:
https://bibliotekanauki.pl/articles/148600.pdf
Data publikacji:
2003
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
1,1-dichloroethene
trichloroethene
electron beam decomposition
theoretical model
kinetics calculation
Opis:
New experimental data related to the removal of C2H2Cl2 and C2HCl3 in dry and humid (300 ppm of H2O) air at atmospheric pressure and a temperature of 25°C under the influence of electron beam in the dose range 1 < D < 100 kGy are published. Taking into account these experimental data, theoretical models of the decomposition of both compounds and computer simulations were performed by the present authors to find the kinetics of such processes. The influence of active atoms Cl, O and OH radicals on the VOC degradation process has been established. The theoretical model of C2H2Cl2 degradation under the influence of electron beam in dry and humid air describes the C2H2Cl2 decay and formation of the main products like Cl2, COCl2, CO, CO2, HCl, HCOCl and C2H2Cl2O. The results of calculation of the kinetics of C2H2Cl2 decomposition were compared with data obtained experimentally for the C2H2Cl2 concentration range 321-2213 ppm. It was established that the relation between the rate constants of intermediate product decomposition: C2H2Cl3O Ţ C2H2Cl2O + Cl; (k1) C2H2Cl3O Ţ COCl2 + CH2C2; (k2) should be k1/k2 = 40. The theoretical model of C2HCl3 degradation under the influence of electron beam in dry and humid air describes the C2HCl3 decay and formation of the main products like Cl2, COCl2, CO, CO2, HCl, HCOCl and C2HCl3O. A detailed comparison of experimental and theoretical data for the C2HCl3 concentration 108-3206 ppm shows that the relation between the rate constants of intermediate product decomposition: C2HCl4O Ţ C2HCl3O + Cl; (k3) C2HCl4O Ţ COCl2 + CHCl2; (k4) should be k3/k4 =10. It was also found that O2+ ions have been formed in a gas mixture as a result of charge transfer process from N2+ ions, partly in excited form, which may lead to charge transfer to C2HCl3 and degradation of those particles. According to performed calculation, it can be stated that in humid air (300 ppm of H2O) VOC degradation is occurring mainly due to a chain reaction stimulated by Cl atoms, but also OH radicals are playing an important role. In the described gas mixture, the OH radicals are formed in the following reactions: O2+) + H2O + M Ţ (O2+)H2O + M O2+ (H2O) + H2O Ţ O2 + (H3O+)OH (H3O+)OH + H2O Ţ H3O+ + OH + H2O VOC degradation process under the influence of electron beam is more effective in humid air than in dry air for the same initial VOC concentration level. This conclusion is also supported by experimental data. --------------------------------------------------------------------------------
Źródło:
Nukleonika; 2003, 48, 1; 45-50
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New bizarre micro-spiriferid brachiopod from the Early Carboniferous of China
Autorzy:
Sun, Y
Balinski, A.
Ma, X.
Zhang, Y.
Powiązania:
https://bibliotekanauki.pl/articles/22087.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Carboniferous
verneuiliid brachiopod
brachiopod
China
Muhua Formation
Verneuiliidae
Early Carboniferous
Brachiopoda
Changshunella yangi
paleontology
Opis:
The verneuiliid brachiopod Changshunella yangi gen. et sp. nov. is described from the Early Carboniferous Muhua Formation of Guizhou, China. This rather unusual form is characterized by having very small shell dimensions (2.6–4 mm in length), a very high flat procline ventral interarea, and by having three prominent plications on both valves that are arranged in opposed folding; the last feature is characteristic for the family Verneuiliidae. We suggest that the family has been derived from an offshoot of the stock that produced the superfamilies Spiriferoidea, Paeckelmanelloidea, and Brachythyridoidea by developing opposed folding and loss of dental plates or dental adminicula as exemplified by Verneuilia and Changshunella gen. nov.
Źródło:
Acta Palaeontologica Polonica; 2004, 49, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electron Transport and Microwave Noise in MBE- and MOCVD-Grown AlGaN/AlN/GaN
Autorzy:
Matulionis, A.
Liberis, J.
Eastman, L. F.
Schaff, W. J.
Shealy, J. R.
Chen, X.
Sun, Y. J.
Powiązania:
https://bibliotekanauki.pl/articles/2041771.pdf
Data publikacji:
2005-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
63.20.Kr
72.20.Ht
73.40.Kp
Opis:
Microwave noise temperature, current, and dissipated power were investigated at room temperature in undoped AlGaN/AlN/GaN channels grown by molecular beam epitaxy and metal-organic compound vapour decomposition techniques. Samples with essentially the same electron density (1×10$\text{}^{13}$ cm$\text{}^{-2}$) and low-field mobility (1150 cm$\text{}^{2}$/(V s)) demonstrated considerably different behaviour at high electric fields. The effective hot-phonon lifetime, 300 fs and 1000 fs, respectively, was estimated for molecular beam epitaxy and metal-organic compound vapour decomposition samples. The expected anti-correlation of hot-phonon lifetime and hot-electron drift velocity was confirmed experimentally.
Źródło:
Acta Physica Polonica A; 2005, 107, 2; 361-364
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Less conservative results for the exponential stability of uncertain time-delay systems
Autorzy:
Sun, Y. J.
Powiązania:
https://bibliotekanauki.pl/articles/970980.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
delay-independent criterion
exponential stability
time-delay systems
Opis:
In this paper, global exponential stability of a class of uncertain systems with multiple time delays is investigated. Simple delay-independent criterion is derived to guarantee the global exponential stability of such systems. The main result is sharper than the recent result reported in the literature. Two numerical examples are also provided to illustrate the main result.
Źródło:
Control and Cybernetics; 2005, 34, 4; 1045-1055
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new aviculopectinid bivalve from the Early Carboniferous of Guizhou, China
Autorzy:
Fang, Z.-J.
Sun, Y.
Balinski, A.
Powiązania:
https://bibliotekanauki.pl/articles/22541.pdf
Data publikacji:
2006
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Aviculopectinidae
Bivalvia
Carboniferous
China
Early Carboniferous
Girtypecten
Guizhou Province
Muhua Formation
Sinopecten
aviculopectinid bivalve
bivalve
paleontology
Opis:
Six silicified left valves including one nearly complete were obtained from acid residues of two samples collected from the Early Carboniferous Muhua Formation in Guizhou Province, China. The Chinese specimens have reticulate ornament and a large asymmetrical aviculopectinid−type resilifer and are much like Girtypecten from Permian rocks in the United States. However, the Chinese material shows only unicostate radial ornament, whereas Girtypecten is multicostate. Thus, a new taxon Girtypecten (Sinopecten) newelli subgen. et sp. nov. is proposed. The conodont assemblage occurring with G. (Sinopecten) newelli dates the new scallop as Tournaisian (the conodont Lower Siphonodella crenulata Zone); this is the oldest known occurrence of Girtypecten.
Źródło:
Acta Palaeontologica Polonica; 2006, 51, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Early and Middle Frasnian brachiopod faunas and turnover on the South China shelf
Autorzy:
Ma, X -P
Becker, R.T.
Li, H.
Sun, Y.-Y.
Powiązania:
https://bibliotekanauki.pl/articles/21029.pdf
Data publikacji:
2006
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Early Frasnian
Middle Frasnian
Frasnian
paleontology
brachiopod fauna
South China shelf
Devonian
Brachiopoda
Cyrtospirifer
faunal turnover
Opis:
The first appearance of the brachiopod Cyrtospirifer and related forms in the Late Devonian of South China significantly postdates the beginning of the Frasnian and the entry of the group in other parts of the world. Scattered data from different sections suggest that its first entry, associated with the emergence of other plicate spiriferids, such as theodossid and conispiriferid brachiopods, was late in the Middle Frasnian. At the same time, many rhynchonellids disappeared or became extinct locally in South China. This brachiopod faunal overturn near the Palmatolepis punctata–Early Pa. hassi zonal boundary is the most significant event in the Early–Middle Frasnian of South China, characterized by about a 35% loss of existing species and the flourishing of the plicate spiriferids, which was coeval with the end of a major biogeochemical perturbation recently recognized in the Pa. punctata Zone. By contrast, atrypid brachiopods do not seem to show any significant diversity change. The brachiopod faunal change was probably related to a (local?) transgressive event in South China, which also brought new pelagic faunas northwards into some intra−shelf deeper water areas, such as the Shetianqiao area in central Hunan Province. Fifteen brachiopod species are described and illustrated, which include some taxa that are first recorded or recognized in South China, e.g., the spiriferid Pyramidaspirifer, which is now known from both North America and South China. One new species, Desquamatia qiziqiaoensis, is erected.
Źródło:
Acta Palaeontologica Polonica; 2006, 51, 4; 789-812
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multivariate statistical analysis of water quality and phytoplankton characteristics in Daya Bay, China, from 1999 to 2002
Autorzy:
Wang, Y.S.
Lou, Z.P.
Sun, C.C.
Wu, M.L.
Han, S.H.
Powiązania:
https://bibliotekanauki.pl/articles/48049.pdf
Data publikacji:
2006
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
South China Sea
water quality
China
phytoplankton
Daya Bay
multivariate statistical analysis
Opis:
This study analyzed seasonal physicochemical and phytoplankton data collected at 12 marine monitoring stations in Daya Bay from 1999 to 2002. Cluster analysis based on water quality and phytoplankton parameters measured at the 12 stations could be grouped into three clusters: cluster I – stations S1,S2 , S7 and S11 in the southern part and the north-eastern part of Daya Bay; cluster II – stations S5, S6,S9 ,S1 0 and S12 in the central and north-eastern parts of Daya Bay; cluster III – stations S3,S 4 and S8 in the cage culture areas in the south-western part of Daya Bay and in the north-western part of the Bay near Aotou harbor. Bivariate correlations between phytoplankton density and the major physical and nutrient factors were calculated for all stations. Factor analysis shows that there were high positive loadings of pH,T IN and the ratio of TIN to PO4-P in the three clusters, which indicates that all the stations in the three clusters were primarily grouped according to their respective nutrient conditions.
Źródło:
Oceanologia; 2006, 48, 2
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chondrichthyan remains from the Lower Carboniferous of Muhua, Southern China
Autorzy:
Ginter, M.
Sun, Y.
Powiązania:
https://bibliotekanauki.pl/articles/22216.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Carboniferous
China
Chondrichthyes
Elasmobranchii
Euchondrocephali
Lower Carboniferous
Muhua
chondrichthyan
remains
tooth
Tournaisian
paleontology
systematics
morphology
Opis:
The shallow water assemblage of chondrichthyan microremains, teeth, tooth plates and scales, from the middle Tournaisian (Mississippian) of the vicinity of Muhua village, Guizhou province, southern China, is thus far the richest and most diverse association of this age collected from a single locality and horizon, and represents a chondrichthyan community very restricted in time and space. It was recovered from a small bioclastic limestone lens, MH−1, occurring among basinal marls near the base of the Muhua Formation, and dated as to the Siphonodella crenulata conodont Zone. The majority of the fauna presented here consists of teeth with euselachian−type bases and crushing crowns belonging to bottom−dwelling durophagous chondrichthyans, most probably feeding on shelly invertebrates such as the abundant brachiopods. We assigned most of these teeth to Euselachii (six species, among them Cassisodus margaritae gen. et sp. nov.), Petalodontiformes (two species), Holocephali (five species), and Euchondrocephali incertae sedis (Cristatodens sigmoidalis gen. et sp. nov.). We also identified primitive polycuspid, clutching teeth representing Phoebodontiformes (Thrinacodus bicuspidatus sp. nov.), Symmoriiformes, and Ctenacanthiformes. The scales are typical growing, compound forms of the protacrodont, ctenacanth, and hybodont types. Two problematic denticulated plates were found, one of which resembles mandibular or palatal plates of Sibyrhynchus (Iniopterygii). Several of the identified chondrichthyan taxa have hitherto been known only from Laurussia, especially from the British Isles and central USA. In particular we found the first record of Chondrenchelyssp. and Diclitodus denshumani outside their type locality. Th. bicuspidatus sp. nov., also known from Nevada, Iran, and NW Australia, appears to be a cosmopolitan, middle Tournaisian index fossil.
Źródło:
Acta Palaeontologica Polonica; 2007, 52, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation of decomposition of dichloroethylenes (trans-DCE, cis-DCE, 1,1-DCE)/air under electron beam irradiation
Autorzy:
Sun, Y.
Chmielewski, G.
Bułka, S.
Zimek, Z.
Nichipor, H.
Powiązania:
https://bibliotekanauki.pl/articles/146568.pdf
Data publikacji:
2007
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
trans-dichloroethylene
cis-dichloroethylene
1,1-dichloroethylene
electron beam
decomposition
mechanism
Opis:
On the basis of the experimental results, computer simulations of decomposition of dichloroethylenes for three isomers (trans-DCE, cis-DCE, 1,1-DCE) in air under electron beam were carried out. Computer code “Kinetic” and “Gear” method were used. Calculation results well agree with the experimental results. Decomposition efficiency of DCE is mainly determined by Cl- dissociated secondary electron attachment, followed by Cl radical addition reaction with DCE.
Źródło:
Nukleonika; 2007, 52, 2; 59-67
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Silicified Mississippian brachiopods from Muhua, Southern China: Lingulids, craniids, strophomenids, productids, orthotetids, and orthids
Autorzy:
Sun, Y
Balinski, A.
Powiązania:
https://bibliotekanauki.pl/articles/22016.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
paleontology
China
Orthida
Craniida
Brachiopoda
Mississippian brachiopod
Carboniferous
Productida
Strophomenida
Orthotetida
silicification
Lingulida
brachiopod
Muhua
Opis:
This paper describes 37 species (4 new) belonging to 27 genera (1 new), 14 families, and 6 orders (Lingulida, Craniida, Strophomenida, Productida, Orthotetida, and Orthida) of silicified brachiopods from the middle Tournaisian (Mississippian, lower Carboniferous) of the vicinity of Gedongguan and Muhua villages (southern China). All specimens come from acid etching of detrital and oolitic limestone lenses scattered within grey to black laminated basinal micrite and marl of the Muhua Formation. The formation, which attains about 1–10 meters in thickness, is dated to the Siphonodella crenulata Zone. More than 10,000 silicified brachiopod specimens belonging to about 70 species were recovered from over 900 kg of the sampled limestone lenses, the most diverse brachiopod fauna of that age. The characteristic feature of the studied material is the prevailing disarticulation and fragmentation of skeletal parts due to their down slope transportation into a deeper water environment. Within Lingulida, one linguloid and one discinoid species are described. Craniida are represented by five species including Nematocrania pilea sp. nov. Strophomenida are represented by fragmentarily preserved specimens belonging to one species. The most diverse are Productida, which are represented by 7 chonetidine and 12 productidine species; new are Subglobosochonetes gedongguanensis sp. nov. and Globosochonetes gracilis sp. nov. New data on morphology of larval stage of Argentiproductus margaritaceus and its mode of attachment are presented. Orthotetida is represented by 5 species including Lamellispina spinosa gen. et sp. nov. Orthida is represented by 3, mostly cosmopolitan species. This study of a middle Tournaisian brachiopod fauna from Muhua, together with published data on the Mississippian brachiopods from other regions of South China, allow to study the Devonian–Carboniferous biotic crisis and post−crisis recovery.
Źródło:
Acta Palaeontologica Polonica; 2008, 53, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Theoretical study of dose and dose rate effect on trichloroethylene (HClC=CCl2) decomposition in dry and humid air under electron beam irradiation
Autorzy:
Nichipor, H.
Yacko, S.
Sun, Y.
Chmielewski, A. G.
Zimek, Z.
Powiązania:
https://bibliotekanauki.pl/articles/146819.pdf
Data publikacji:
2008
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
trichloroethylene
electron beam decomposition
computer simulation
Opis:
Experimental data related to C2HCl3 (TCE) removal in dry and humid (200-1000 ppm of H2O) air, respectively, in ambient conditions under electron beam irradiation in the dose range of 1-40 kGy has been published in the literature. Based on the experimental results a theoretical model of C2HCl3 decomposition was proposed for the kinetic mechanism of such process. The active radicals of Cl, O and OH play an important role in the decomposition of TCE. According to the calculations performed, the Cl- dissociative electron attachment predominates in the initial stage of C2HCl3 decomposition. Cl radical accelerates this degradation by chain process in both humid and dry air, respectively. The OH radical produced in humid air also enhances the decomposition process of TCE.
Źródło:
Nukleonika; 2008, 53, 1; 11-16
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 118

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