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AN ALABASTER SCULPTED HEADOFPTOLEMY V FROM THE PUSHKIN MUSEUMOFFINEARTS,MOSCOW,ANDHORUSASPECTS OF LATE PERIOD EGYPTIAN AND PTOLEMAIC KINGSHIP

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Journal of Ancient Civilizations 2023年第1期38卷 1-20,125页

作者： ivan A.Ladynin M.V.Lomonosov Moscow State University MoscowRussia

The typology of Ptolemaic royal sculpture has served as a theme of research for a number of scholars who have managed to achieve impressive results:two fundamental works must be *** earlier is Bildnisse der Ptolemaer by ***,which established a convincing correspondence between the well-attributed images of the Ptolemaic kings on their coins and their mostly uninscribed sculpted images.'The history of the research reveals that although the corpus of Ptolemaic sculpture gradually expanded,due to new finds and new publications,challenges to specific attributions proposed by Kyrieleis often proved to be a failure?A later work deserving a special mention is Portraits of the Ptolemies by ***,which proposed a well-founded scheme for the evolution of the Ptolemaic royal sculpture dividing it into nine groups(Groups A-E,G making a chronological sequence,Groups F,H-J uncertain and miscellaneous)'Quite expectedly,a problematic issue is the ultimate motive and final result of shifting from one such group to another:a grouping of objects is largely a formal task,and a scholar performing it is unlikely to concentrate simultaneously on the variety of political,ideological,and religious factors that could lie behind the emergence of the groups *** present article aims to offer a tentative explanation for the shift in the style of Ptolemaic sculpture that took place at the cusp of the 3rd and 2nd centuries BC,i.e.,the transition between Stanwick's "Group A"and "Group B."

关键词： dividing religious shifting

Electrofishing method improves evaluation of amphibian larvae abundance:a case of“beaver rivers”

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Integrative Zoology 2017年第4期12卷 345-350页

作者： Yury Y.DGEBUADZE ivan V.BASHINSKIY Severtsov Institute of Ecology&Evolution Leninsky ProspectMoscowRussia

There are many locations in Russia where Eurasian beaver(Castor fiber)populations have been *** a keystone species,beavers provide wide-ranging direct and indirect impacts on aquatic *** particular,beaver-created ponds are sites for spawning and nursery places for tadpoles of the brown frogs(genus Rana).Because of such impacts,study techniques for assessing aquatic organism abundance are being *** compared two methods for estimating tadpole abundance:traditional catches by dipnet and *** results show that the dipnet catch data for the shallower ponds with larger water surface area were five times lower than that obtained by ***,we conclude that dipnet catches are not suitable for comparing the relative abundance of tadpoles in the two beaver ponds that were studied.

关键词： abundance of tadpoles beaver ponds Rana

Market Power of Coordinated Hydro-wind Joint Bidding:Croatian Power System Case Study

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Journal of Modern Power Systems and Clean Energy 2022年第2期10卷 531-541页

作者： Perica Ilak Igor Kuzle Lin Herencic Josip Dakovic ivan Rajsl the University of Zagreb Faculty of Electrical Engineering and ComputingZagrebCroatia

The paper analyses the coordinated hydro-wind power generation considering joint bidding in the electricity *** impact of mutual bidding strategies on market prices,traded volumes,and revenues has been *** coordination assumes that hydro power generation is scheduled mainly to compensate the differences between actual and planned wind power *** potential of this coordination in achieving and utilizing of market power is *** market equilibrium of asymmetric generation companies is analyzed using a game theory *** assumed market situation is imperfect competition and non-cooperative game.A nu-merical approximation of the asymmetric supply function equilibrium is used to model this *** introduced novelty is the application of an asymmetric supply function equilibrium approximation for coordinated hydro-wind power *** model is tested using real input data from the Croatian power system.

关键词： Asymmetric firm bidding strategy coordination hydro power wind power imperfect competition market power non-cooperative game optimal bidding strategy supply function equilibrium

Mechanochemical Synthesis and Characterization of Nanocrystalline Copper-Cobalt Ferrites

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Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 367-372页

作者： Nikolay Velinov Dimitar Dimitrov Kremena Koleva Krassimir ivanov ivan Mitov Institute of Catalysis Bulgarian Academy of Sciences Department of Chemistry Agricultural University

Nanocrystalline copper-cobalt ferrites with composition Cu_（1-x）Co_xFe_2O_4,where x = 0.2 and 0.8,were synthesized by mechanochemical treatment of co-precipitated *** ferrite powders were characterized by XRD and Mossbauer *** proved obtaining of spinel ferrites with crystallite size smaller than 10 *** of crystallite size of samples with increasing of mechanochemical treatment duration was established,*** properties of obtained ferrites were tested in reactions of oxidation of CO,methanol and dimethyl *** catalytic activity of nanocrystalline copper-cobalt ferrites toward CO and CH_3OH（about 100% conversions of CO and CH_3OH at 160 ℃）and moderate activity toward（CH_3）_2O oxidation were *** results obtained revealed that the Co/Cu atomic ratio is an important factor determinant the behavior of catalysts toward methanol and DME oxidation.

关键词： Mechanochemical synthesis Nanocrystalline Ferrites Mossbauer spectroscopy Catalysis

Predator-induced physiological responses in tadpoles challenged with herbicide pollution

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Current Zoology 2013年第4期59卷 475-484页

作者： Pablo BURRACO Lidia Jimenez DUARTE ivan GOMEZ-MESTRE Ecology Evolution and Development Group Estaci6n Biol6gica de Dofiana (EBD-CSIC) E-41092 Seville Spain Av. Las Ciencias 4 2℃ 41020 Sevilla Spain

Predators induce plastic responses in multiple prey taxa, ranging from morphological to behavioral or physiological changes. In amphibians, tadpoles activate plastic responses to reduce predation risk by reducing their activity rate and altering their morphology, specifically tail depth and pigmentation. Furthermore, there is now evidence that tadpoles＇ defenses are modi- fied when predators combine with other stressful factors such as pollutants or competitors, but our knowledge on the physiologi- cal responses underlying these responses is still scarce. Here we study physiological responses in Pelobates cultripes tadpoles exposed to a natural predator （larvae of the aquatic beetle Dytiscus circumflexus）, non-lethal concentrations of herbicide （gly- phosate, 0.5 mg/L and 1.0 mg/L） or both factors combined. We measured corticosterone levels, standard metabolic rate, oxidative damage （TBARS） and activity of antioxidant enzymes, and immune response （via leukocyte count）. Tadpoles reduced their corti- costerone concentration by ca. 24% in the presence of predator cues, whereas corticosterone did not change in the presence of glyphosate. Two enzymes involved in antioxidant response also decreased in the presence of predators （14.7% and 13.2% respec- tively） but not to glyphosate. Herbicide, however, increased the number of neutrophils and reduced that of lymphocytes, and had an interaction effect with predator presence. Standard metabolic rate did not vary across treatments in our experiment. Thus we show a marked physiological response to the presence of predators but little evidence for interaction between predators and low levels of herbicide. Multiple assessment of the physiological state of animals is important to understand the basis and conse- quences ofphenotypic plasticity

关键词： Inducible defenses Physiological responses Corticosterone Glyphosate Spadefoot toads Oxidative stress

Abundance and spatial dynamics of bacterioplankton in the Seven Rila Lakes,Bulgaria

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Chinese Journal of Oceanology and Limnology 2010年第3期28卷 451-458页

作者： Silvena BOTEVA ivan TRAYKOV Anelia KENAROVA Valentin BOGOEV Biology Faculty Sofia University"St. Kliment Ohridski"8 Dragan Tzankov Blvd. 1611 Sofia Bulgaria

In the high mountain oligotrophic Seven Rila Lakes (2 095–2 535 m a.s.l.) bacterial abundance was recorded in July and September 2006. In July, bacterial abundance (average (3.32±2.5)×105 cell/ml) in the lakes correlated negatively with elevation, while in September (average (26.39±7.1)×105 cell/ml) this pattern was altered and the greatest abundance of bacteria occurred at the highest ((39.05±1.5)×105 cell/ml) and the lowest ((30.63±6.0)×105 cell/ml) elevated lakes. Regression analyses suggested that the principal factor controlling bacterial abundance, in both July and September, was inorganic nitrogen (NO3-N and NH4-N; R2=0.70, P<0.05). Other major regulating factors were temperature (R2=0.66, P<0.03) in July and filter-feeding zooplankton (R2=0.95, P<0.01) in September. All factors, except NO3-N, had a positive effect on bacterial abundance.

关键词： bacterial abundance high mountain lake Rila Mountain environmental factor bottom-up control

Modular Timing Constraints for Delay-Insensitive Systems

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Journal of Computer Science & Technology 2016年第1期31卷 77-106页

作者： Hoon Park Anping He Marly Roncken Xiaoyu Song ivan Sutherland Asynchronous Research Center Portland State University Portland OR 97201 U.S.A. Department of Electrical and Computer Engineering Portland State University Portland OR 97201 U.S.A. School of Information Science and Engineering Lanzhou University Lanzhou 730000 China

This paper introduces ARCtimer, a framework for modeling, generating, verifying, and enforcing timing constraints for individual self-timed handshake components. The constraints guarantee that the component＇s gate-level circuit implementation obeys the component＇s handshake protocol specification. Because the handshake protocols are delayinsensitive, self-timed systems built using ARCtimer-verified components are also delay-insensitive. By carefully considering time locally, we can ignore time globally. ARCtimer comes early in the design process as part of building a library of verified components for later system use. The library also stores static timing analysis （STA） code to validate and enforce the component＇s constraints in any self-timed system built using the library. The library descriptions of a handshake component＇s circuit, protocol, timing constraints, and STA code are robust to circuit modifications applied later in the design process by technology mapping or layout tools. In addition to presenting new work and discussing related work, this paper identifies critical choices and explains what modular timing verification entails and how it works.

关键词： self-timed circuit delay-insensitive system model checking timing analysis design pattern

Winkler Support Model and Nonlinear Boundary Conditions Applied to 3D Elastic Contact Problem Using the Boundary Element Method

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Acta Mechanica Solida Sinica 2019年第2期32卷 230-248页

作者： J.Vallepuga-Espinosa Lidia Sanchez-Gonzalez ivan Ubero-Martinez Departamento de Tecnologia Minera Topografiay de EstructurasUniversidad de LeonCampus de Vegazana s/n24071 LeonSpain Departamento de Ingenierias Mecanica Informatica y AeroespacialUniversidad de LeonCampus de Vegazana s/n24071 LeonSpain

This work presents a numerical methodology for modeling the Winkler supports and nonlinear conditions by proposing new boundary conditions. For the boundary conditions of Winkler support model, the surface tractions and the displacements normal to the surface of the solid are unknown, but their relationship is known by means of the ballast coefficient, whereas for nonlinear boundary conditions, the displacements normal to the boundary of the solid are zero in the positive direction but are allowed in the negative direction. In those zones, detachments of nodes might appear, leading to a nonlinearity, because the number of nodes that remain fixed or of the detached ones (under tensile tractions) is unknown. The proposed methodology is applied to the 3D elastic receding contact problem using the boundary element method. The surface t r actions and the displacements of the common int erface bet ween the two solids in contac t under the influence of different supports are calculated as well as the boundary zone of the solid where the new boundary conditions are applied. The problem is solved by a double-iterative met hod, so in the final solut ion, t here are no t r act ions or pene trations between the two solids or at the boundary of the solid where the nonlinear boundary conditions are Simula ted. The effectiveness of the proposed method is verified by examples.

关键词： Boundary element method Elastic contact problem Winkler support model Nonlinear boundary conditions

Determination of Vertices and Edges in a Parametric Polytope to Analyze Root Indices of Robust Control Quality

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International Journal of Automation and computing 2019年第6期16卷 828-837页

作者： Sergey Gayvoronskiy Tatiana Ezangina ivan Khozhaev Viktor Kazmin School of Computer Science and Robotics National Research Tomsk Polytechnic University

The research deals with the methodology intended to root robust quality indices in the interval control system, the parameters of which are affinely included in the coefficients of a characteristic polynomial. To determine the root quality indices we propose to depict on the root plane not all edges of the interval parametric polytope(as the edge theorem says), but its particular vertex-edge route. In order to define this route we need to know the angle sequence at which the edge branches depart from any integrated pole on the allocation area. It is revealed that the edge branches can integrate into the route both fully or partially due to intersection with other branches. The conditions which determine the intersection of one-face edge images have been proven. It is shown that the root quality indices can be determined by its ends or by any other internal point depending on a type of edge branch. The conditions which allow determining the edge branch type have been identified. On the basis of these studies we developed the algorithm intended to construct a boundary vertex-edge route on the polytope with the interval parameters of the system. As an illustration of how the algorithm can be implemented, we determined and introduced the root indices reflecting the robust quality of the system used to stabilize the position of an underwater charging station for autonomous unmanned vehicles.

关键词： Robust control parametric uncertainty parametric polytope interval parameters system analysis