Dynamics of the vortex-particle complexes bound to the free surface of superfluid helium

We present an experimental and theoretical study of the 2D dynamics of electrically charged nanoparticles trapped under a free surface of superfluid helium in a static vertical electric field. We focus on the dynamics of particles driven by the interaction with quantized vortices terminating at the free surface. We identify two types of particle trajectories and the associated vortex structures: vertical linear vortices pinned at the bottom of the container and half-ring vortices travelling along the free surface of the liquid

Dynamics of fine particles due to quantized vortices on the surface of superfluid 4^4He

Peculiar dynamics of a free surface of the superfluid 4He has been observed experimentally with a newly established technique utilizing a number of electrically charged fine metal particles trapped electrically at the surface by Moroshkin et al. They have reported that some portion of the particles exhibit some irregular motions and suggested the existence of quantized vortices interacting with the metal particles. We have conducted calculations with the vortex filament model, which turns out to support the idea of the vortex-particle interactions. The observed anomalous metal particle motions are roughly categorized into two types; (1) circular motions with specific frequencies, and (2) quasi-linear oscillations. The former ones seem to be explained once we consider a vertical vortex filament whose edges are terminated at the bottom and at a particle trapped at the surface. Although it is not yet clear whether all the anomalous motions are due to the quantum vortices, the vortices seem to play important roles for the motions.Comment: 7 pages, 10 figure

Buried double CuO chains in YBa2_2Cu4_4O8_8 uncovered by nano-ARPES

The electron dynamics in the CuO chains has been elusive in Y-Ba-Cu-O cuprate systems by means of standard angle-resolved photoemission spectroscopy (ARPES); cleaved sample exhibits areas terminated by both CuO-chain or BaO layers, and the size of a typical beam results in ARPES signals that are superposed from both terminations. Here, we employ spatially-resolved ARPES with submicrometric beam (nano-ARPES) to reveal the surface-termination-dependent electronic structures of the double CuO chains in YBa$_2$Cu$_4$O$_8$. We present the first observation of sharp metallic dispersions and Fermi surfaces of the double CuO chains buried underneath the CuO$_2$-plane block on the BaO terminated surface. While the observed Fermi surfaces of the CuO chains are highly one-dimensional, the electrons in the CuO-chains do not undergo significant electron correlations and no signature of a Tomonaga-Luttinger liquid nor a marginal Fermi liquid is found. Our works represent an important experimental step toward understanding of the charge dynamics and provides a starting basis for modelling the high-$T_c$ superconductivity in YBCO cuprate systems.Comment: 10 pages, 5 figures including supplementary material (4 pages, 2 figures

Continuous deformations of the Grover walk preserving localization

The three-state Grover walk on a line exhibits the localization effect characterized by a non-vanishing probability of the particle to stay at the origin. We present two continuous deformations of the Grover walk which preserve its localization nature. The resulting quantum walks differ in the rate at which they spread through the lattice. The velocities of the left and right-traveling probability peaks are given by the maximum of the group velocity. We find the explicit form of peak velocities in dependence on the coin parameter. Our results show that localization of the quantum walk is not a singular property of an isolated coin operator but can be found for entire families of coins

Соотношение путей углеводного синтеза при введении свободных и фосфорилированных сахаров в листья картофеля

Показано, что регуляция путей биосинтеза углеводов может осуществляться через изменение концентрации промежуточных и конечных метаболитов. При этом одним из факторов, регулирующих направленность синтеза углеводов, является активность АДФГ- и УДФГ-пирофосфорилаз. По-видимому, регуляция работы этих ферментов может осуществляться низкомолекулярными метаболитами по принципу обратной связи

Neural architectures for fine-grained entity type classification

In this work, we investigate several neural network architectures for fine-grained entity type classification and make three key contributions. Despite being a natural comparison and addition, previous work on attentive neural architectures have not considered hand-crafted features and we combine these with learnt features and establish that they complement each other. Additionally, through quantitative analysis we establish that the attention mechanism learns to attend over syntactic heads and the phrase containing the mention, both of which are known to be strong hand-crafted features for our task. We introduce parameter sharing between labels through a hierarchical encoding method, that in lowdimensional projections show clear clusters for each type hierarchy. Lastly, despite using the same evaluation dataset, the literature frequently compare models trained using different data. We demonstrate that the choice of training data has a drastic impact on performance, which decreases by as much as 9.85% loose micro F1 score for a previously proposed method. Despite this discrepancy, our best model achieves state-of-the-art results with 75.36% loose micro F1 score on the well-established FIGER (GOLD) dataset and we report the best results for models trained using publicly available data for the OntoNotes dataset with 64.93% loose micro F1 score

Glykolivesien ohjausjärjestelmän järjestelmäkuvaus

Tämä insinöörityö toteutettiin Helsinki-Vantaan lentoasemaa hallinnoivalle Finavia Oyj:lle. Työn tavoitteena oli selvittää lentokentän hulevesien ohjausjärjestelmän toimintaa ja luoda siitä Finavian käyttöön selkeät dokumentit toimintaselostuksineen. Luotua materiaalia voidaan käyttää järjestelmää tuntemattomien henkilöiden perehdyttämiseen sekä pohjamateriaalina mahdollisille järjestelmän muutostöille tulevaisuudessa. Lentokoneiden jäänestoaineena käytetään propyleeniglykolia, jonka ympäristöä kuormittavien ominaisuuksien takia sitä ei ole suotavaa johtaa luontoon lentoaseman hulevesien mukana. Lentoaseman suuren pinta-alan vuoksi hulevesien muodostuminen on ajoittain hyvin runsasta. Huleveden ohjaus prosessissa ja sen loppusijoittaminen riippuvat sen laadusta ja glykolipitoisuudesta. Työn aluksi selvitettiin ja listattiin kaikki hulevesien hallintaan liittyvät prosessit ja kiinteistönumerot. Jokaiseen saavutettavissa olevaan kohteeseen käytiin tutustumassa prosessiin ja sen laitteistoon luoden muistiinpanoja. Myös asiantuntijoita haastateltiin. Kohteista laadittiin säätökaaviot sekä toimintaselostukset muistiinpanojen ja jo olemassa olleiden dokumenttien perusteella. Tämän insinöörityön tuloksena saatiin Finavian käyttöön kirjallinen yhteenveto jäänpoisto- ja -estokäsittelyiden vaikutuksesta hulevesien hallintaan Helsinki-Vantaan lentoasemalla sekä prosessikohtaiset säätökaaviot lyhyine toimintaselostuksineen.This thesis was made for Finavia plc., which maintains and manages the Helsinki Airport. The goal of this thesis was to research the control systems of runoff waters at Helsinki airport and create documents with diagrams and descriptions. The created documents can be used for briefing new people and for base information when the system is developed further. The used chemical for airplane de-icing and anti-icing procedures is propylene glycol which burdens the environment. This is why the runoff waters of Helsinki airport are controlled. The large area of Helsinki airport creates a lot of urban runoff waters. The controlling and destination of runoff waters depends on its quality. The first step in this study was to investigate all the processes and properties related to control system of runoff waters. All the process-related properties were visited and equipment reviewed, based on which notes were made. Specialists were also interviewed. Every part of the processes was documented with diagrams and descriptions. As a result of this thesis a compact research of the effects of de-icing and anti-icing procedures for controlling the runoff waters was created. The thesis contains diagrams and descriptions of every part of the processes

X-Ray Observations of the Galactic Center with Suzaku

We report on the diffuse X-ray emissions from the Galactic center (GCDX) observed with the X-ray Imaging Spectrometer (XIS) on board the Suzaku satellite. The highly accurate energy calibrations and extremely low background of the XIS provide many new facts on the GCDX. These are (1) the origin of the 6.7/7.0keV lines is collisional excitation in hot plasma, (2) new SNR and super-bubble candidates are found, (3) most of the 6.4keV line is fluorescence by X-rays, and (4) time variability of the 6.4keV line is found from the SgrB2 complex.Comment: 4 pages, 6 figure, proceedings of the XMM-Newton workshop, June 2007, accepted for publication in A

Estimation of the order parameter exponent of critical cellular automata using the enhanced coherent anomaly method.

The stochastic cellular automaton of Rule 18 defined by Wolfram [Rev. Mod. Phys. 55 601 (1983)] has been investigated by the enhanced coherent anomaly method. Reliable estimate was found for the $\beta$ critical exponent, based on moderate sized ($n \le 7$) clusters.Comment: 6 pages, RevTeX file, figure available from [email protected]