44 research outputs found
Repeated games with asymmetric information and random price fluctuations at finance markets : the case of countable state space
No full textThis paper is concerned with multistage bidding models introduced by De Meyer and Moussa Saley (2002) to analyze the evolution of the price system at finance markets with asymmetric information. The zero-sum repeated games with incomplete information are considered modeling the bidding with countable sets of possible prices and admissible bids. It is shown that, if the liquidation price of a share has a finite variance, then the sequence of values of n-step games is bounded and converges to the value of the game with infinite number of steps. We construct explicitly the optimal strategies for this game. The optimal strategy of Player 1 (the insider) generates a symmetric random walk of posterior mathematical expectations of liquidation price with absorption. The expected duration of this random walk is equal to the initial variance of liquidation price. The guaranteed total gain of Player 1 (the value of the game) is equal to this expected duration multiplied with the fixed gain per step.Multistage bidding, asymmetric information, repeated games, optimal strategy.
Repeated games with asymmetric information modeling financial markets with two risky assets
No full textWe consider multistage bidding models where two types of risky assets (shares) are traded
between two agents that have different information on the liquidation prices of traded
assets. These prices are random integer variables that are determined by the initial
chance move according to a probability distribution p over the
two-dimensional integer lattice that is known to both players. Player 1 is informed on the
prices of both types of shares, but Player 2 is not. The bids may take any integer values.
The model of n-stage bidding is reduced to a zero-sum repeated game with
lack of information on one side. We show that, if liquidation prices of shares have finite
variances, then the sequence of values of n-step games is bounded. This makes it
reasonable to consider the bidding of unlimited duration that is reduced to the infinite
game G∞(p). We give the solutions for these
games. Optimal strategies of Player 1 generate random walks of transaction prices. But
unlike the case of one-type assets, the symmetry of these random walks is broken at the
final stages of the game
TREATMENT RESULTS OF PATIENTS WITH FRACTURE-DISLOCATION OF THE FOREARM BONES
No full textPurpose of the study: to analyze the treatment results of fracture dislocations of the forearm bones.
Materials and research methods. In the traumatology department of the KP “Dnepropetrovsk Regional Clinical Hospital named after I.I. Mechnikov "DOR" 63 patients with fracture dislocations of the proximal forearm bones has been trested from 2016 to 2020. Taking into account the peculiarities of damage to the stability components of the elbow joint, all patients were divided into 3 groups depending on the type of damage to various anatomical stabilizers of the elbow joint: dislocation fractures of the Monteggi type, fractures of Malgene dislocation (through-olecranial fractures), “terrible triad”.
Results. In the Monteggi fracture dislocation group (n = 24), excellent and good long-term functional results in 16.7% and 45.8% of patients, respectively, satisfactory - in 20.8% and unsatisfactory - in 16.7%. In the Malgeny fracture dislocation group, the majority of patients had excellent and good results - 14 (87.5%), satisfactory - in 2 (12.5%), there were no unsatisfactory results. In the group "terrible triad of the elbow joint" excellent results were obtained in 3 cases (15.8%), good - in 7 (36.8%), satisfactory - in 4 (21.1%), and unsatisfactory - in 5 (26 , 3%).
Conclusions. Stable-functional osteosynthesis with the restoration of bone and soft tissue stabilizers of the elbow joint, with the possibility of active early restoration of the function of the elbow joint, help to reduce the period of disability and give positive results in 84.7% of patients
The results of use of myoplasty for closure of the pelvic floor defect after extralevator abdominoperineal excision of the rectum
No full textBackground. Extralevator abdominoperineal excision is associated with a high incidence of perineal wound complications. There is no uniform standard for choosing the method for pelvic floor reconstruction after extralevator abdominoperineal excision.The purpose of the study was to compare the results of extralevator abdominoperineal excisions of the rectum using various methods of perineal wound closure.Materials and Methods. Between 2014 and 2018, 120 patients underwent extralevator abdominoperineal excisions of the rectum using various options for closure of the pelvic floor. The patients were divided into 3 groups. Group I patients (n=64) underwent simple plasty of the peritoneal wound. Group II patients (n=43) underwent myoplasty using the gluteus maximus muscle. Group III patients (n=13) underwent myoplasty using the rectus abdominis muscle. The incidence of perineal wound complications in the early postoperative period was assessed.Results. The total number of perineal wound complications in Group I, II and III was 33 (51.5 %), 13 (30.2 %), and 6 (46.1 %), respectively. Grade IIIA-IIIB complications according to the Clavien-Dindo classification were observed in 25 % of Group I patients, in 18.6 % of Group II patients and in 7.7 % of Group II patients. Postoperative perineal wound complications occurred more often in Group I patients after simple plasty than in Group II and III patients after myoplasty (51.5 % versus 30.2 %). However, perineal wound complications were observed more often in Group III than in Group II (46.1 % versus 30.2 %, respectively). No significant differences in the frequency of complications between 3 groups were found.Conclusion. Using various options for closure of the pelvic floor after extralevator abdominoperineal excisions of the rectum, there was a tendency to reduction in the incidence of grade IIIA-IIIB perineal wound complications
Repeated games with asymmetric information and random price fluctuations at finance markets : the case of countable state space
No full textURL des Documents de travail : http://ces.univ-paris1.fr/cesdp/CESFramDP2009.htmClassification JEL : C73, D82, D44.Documents de travail du Centre d'Economie de la Sorbonne 2009.40 - ISSN : 1955-611XThis paper is concerned with multistage bidding models introduced by De Meyer and Moussa Saley (2002) to analyze the evolution of the price system at finance markets with asymmetric information. The zero-sum repeated games with incomplete information are considered modeling the bidding with countable sets of possible prices and admissible bids. It is shown that, if the liquidation price of a share has a finite variance, then the sequence of values of n-step games is bounded and converges to the value of the game with infinite number of steps. We construct explicitly the optimal strategies for this game. The optimal strategy of Player 1 (the insider) generates a symmetric random walk of posterior mathematical expectations of liquidation price with absorption. The expected duration of this random walk is equal to the initial variance of liquidation price. The guaranteed total gain of Player 1 (the value of the game) is equal to this expected duration multiplied with the fixed gain per step.Cet article s'intéresse aux modèles d'enchères multipériodes introduit par De Meyer et Moussa Saley (2002) pour analyser l'évolution du système des prix sur les marchés financiers avec information asymmetrique. Des jeux répétés à somme nulle et information incomplète sont utiliser pour modéliser les offres avec des ensembles dénombrables de prix possibles et d'offres admissibles. Cet article montre que si la valeur de liquidation d'un actif a une variance finie, alors la suite des valeurs du jeux en n étapes est bornée et converge vers la valeur du jeu infiniment répété. Les stratégies optimales sont construites explicitement pour ce dernier jeu. La stratégie optimale du joueur informé génère une marche aléatoire symétrique absorbée représentant les espérances conditionnelles successives de la valeur de liquidation. Le temps moyen avant absorption de cette marche aléatoire est égal à la variance initiale de cette valeur de liquidation. La valeur de ce jeu est égal à cette durée moyenne multipliée par un gain fixe par étape
Repeated games with asymmetric information and random price fluctuations at finance markets : the case of countable state space.
No full textThis paper is concerned with multistage bidding models introduced by De Meyer and Moussa Saley (2002) to analyze the evolution of the price system at finance markets with asymmetric information. The zero-sum repeated games with incomplete information are considered modeling the bidding with countable sets of possible prices and admissible bids. It is shown that, if the liquidation price of a share has a finite variance, then the sequence of values of n-step games is bounded and converges to the value of the game with infinite number of steps. We construct explicitly the optimal strategies for this game. The optimal strategy of Player 1 (the insider) generates a symmetric random walk of posterior mathematical expectations of liquidation price with absorption. The expected duration of this random walk is equal to the initial variance of liquidation price. The guaranteed total gain of Player 1 (the value of the game) is equal to this expected duration multiplied with the fixed gain per step.Multistage bidding, asymmetric information, repeated games, optimal strategy.
Результаты использования миопластики для закрытия дефекта тазового дна после экстралеваторной брюшно-промежностной экстирпации прямой кишки
No full textBackground. Extralevator abdominoperineal excision is associated with a high incidence of perineal wound complications. There is no uniform standard for choosing the method for pelvic floor reconstruction after extralevator abdominoperineal excision.The purpose of the study was to compare the results of extralevator abdominoperineal excisions of the rectum using various methods of perineal wound closure.Materials and Methods. Between 2014 and 2018, 120 patients underwent extralevator abdominoperineal excisions of the rectum using various options for closure of the pelvic floor. The patients were divided into 3 groups. Group I patients (n=64) underwent simple plasty of the peritoneal wound. Group II patients (n=43) underwent myoplasty using the gluteus maximus muscle. Group III patients (n=13) underwent myoplasty using the rectus abdominis muscle. The incidence of perineal wound complications in the early postoperative period was assessed.Results. The total number of perineal wound complications in Group I, II and III was 33 (51.5 %), 13 (30.2 %), and 6 (46.1 %), respectively. Grade IIIA-IIIB complications according to the Clavien-Dindo classification were observed in 25 % of Group I patients, in 18.6 % of Group II patients and in 7.7 % of Group II patients. Postoperative perineal wound complications occurred more often in Group I patients after simple plasty than in Group II and III patients after myoplasty (51.5 % versus 30.2 %). However, perineal wound complications were observed more often in Group III than in Group II (46.1 % versus 30.2 %, respectively). No significant differences in the frequency of complications between 3 groups were found.Conclusion. Using various options for closure of the pelvic floor after extralevator abdominoperineal excisions of the rectum, there was a tendency to reduction in the incidence of grade IIIA-IIIB perineal wound complications.Введение. Экстралеваторная брюшно-промежностная экстирпация связана с большой частотой послеоперационных осложнений со стороны промежностной раны. В литературе нет единых стандартных рекомендаций по выбору метода пластики дефекта тазового дна.Целью исследования является сравнение результатов использования простой пластики, пластики лоскутом ягодичной мышцы и лоскутом прямой мышцы живота при закрытии промежностной раны после экстралеваторной брюшнопромежностной экстирпации прямой кишки.Материал и методы. Проведен анализ результатов лечения 120 больных, которым в период с 2014 по 2018 г. выполнена экстралеваторная брюшнопромежностная экстирпация с использованием различных методов закрытия дефекта тазового дна. В зависимости от способа промежностной пластики больные были разделены на три группы. В I группе (n=64) пациентам выполнена простая пластика промежностной раны, во II группе (n=43) - миопластика с использованием большой ягодичной мышцы, в III группе (n=13) - миопластика с использованием прямой мышцы живота. Оценивались частота и характер осложнений со стороны промежностной раны в раннем послеоперационном периоде.Результаты. Общее количество осложнений со стороны промежности в первой группе составило 33 (51,5 %), во второй - 13 (30,2 %), в третьей группе - 6 (46,1 %) случаев. «Большие» осложнения (NIA-ШВ степени по классификации Clavien-Dindo) в I группе возникли у 25 %, во II группе - у 18,6 %, в III группе - у 7,7 % больных. Независимо от методики миопластики (II и III группы) при этих операциях послеоперационные осложнения промежностной раны наблюдались реже - 30,2 %, чем после простой пластики (I группа), - 51,5 % случаев. Однако в третьей группе осложнения встречались чаще, чем во второй, - 46,1 и 30,2 % соответственно. Значимых различий в частоте осложнений во всех трех группах не выявлено.Заключение. При использовании различных вариантов миопластики после экстралеваторной брюшно-промежностной экстирпации прямой кишки наблюдается тенденция к уменьшению частоты «больших» осложнений со стороны промежностной раны
An integrated study of parallel valveless micropumps
No full textThis paper was presented at the 2nd Micro and Nano Flows Conference (MNF2009), which was held at Brunel University, West London, UK. The conference was organised by Brunel University and supported by the Institution of Mechanical Engineers, IPEM, the Italian Union of Thermofluid dynamics, the Process Intensification Network, HEXAG - the Heat Exchange Action Group and the Institute of Mathematics and its Applications.We describe an analytical, computational and experimental study of parallel valveless micropumps. A one dimensional model of a parallel micropump is presented and compared with available experimental data. The model confirms the linear decrease of the volume flux with pressure rise which is consistent with the experiments. The computational study showed a similar linear decrease but highlighted the effect of turbulence closures on the rectified mean flow, with the experimental data sitting between the turbulent and laminar closure regimes. The experimental study confirmed the importance of the displacement distance of fluid through the nozzle compared to nozzle length in the setting whether the flow regime is streaming or rectified. General conclusions are made about how to improve the pumping efficiency of micropumps.This study is supported by the Dorothy Hodgkin Postgraduate Award (DHPA) of the Engineering and Physical Sciences Research Council (EPSRC) of United Kingdom and Ebara Research Co. Ltd of Japan
Mapping of mobile charges on insulator surfaces with the electrostatic force microscope
No full textjournal articleMigration of surface ions in lateral fields on insulator surfaces may modify the electrical characteristics of underlying semiconductor structures causing device instabilities. A high sensitivity electrostatic force microscope is used to image the movement and spatial distribution of surface ions on Si3N4. Mobile surface ions are distributed by the fringing fields of a p-n junction and an open-gate field-effect transistor. The surface charge distribution and topography are imaged simultaneously on a micrometer scale
Dialogue as a Literary Concept
No full textThis article is devoted to the consideration of the concept of “dialogue” as a literary phenomenon. It provides different options for using the concept of “dialogue” in different contexts, such as dialogue of cultures, timeless dialogue between authors and their texts (intertextuality), as well as the dialogue between the author and the reader through the text of a work of art and the dialogue between the reader and the text. The various meanings of the above term are revealed, for example, interaction and interpenetration of different cultures, a reflection of socio-cultural changes in society and the country by the authors of works, dialogues of characters as an element of artistic speech, and composition of a work. At the same time, it is noted that dialogue as a form of artistic speech performs its functions in each literary genus, and each has its own characteristics. This article is based on the study of opinions on the essence of the dialogue of such famous literary scholars of the past as M. Bakhtin, R. Barth, G. Bloom, as well as the works of modern scientists A. Valipur, V. Domansky, M. Krongauz, and A. Smolina. When writing the article, the cultural-historical, historical-theoretical method, the method of comparative studies, and the method of hermeneutics were used. As a result of the research carried out, a conclusion was made about the versatility and scale of the concept of “dialogue” in literary criticism, as well as the importance and necessity of analyzing dialogue from various angles. This article can be used by students-philologists in preparation for practical classes within the discipline “Theory of Literature”, as well as when writing term papers, final qualification works, and master's theses in literature; language teachers can rely on the material of the article when preparing for literature lessons at school
