До історії підготовки інженерів сільськогосподарського машинобудування та тракторобудування в київському політехнічному інституті

У статті висвітлено історію підготовки інженерів сільськогосподарського машинобудування і тракторобудування в КПІ у 1921-1934 рр.In this article the history of preparing of engineers of the agricultural machine building industry and the tractor building industry in the Kyiv polytechnic institute in period from 1921 till 1934 had been considered.В статье освещается история подготовки инженеров сельскохозяйственного машиностроения и тракторостроения в КПИ в период 1921-1934 гг

Labour frictions in interwar Britain: industrial reshuffling and the origin of mass unemployment

This article estimates the matching function of the British labour market for the period of 1921-1934. Changes in matching efficiency can explain both employment resilience during the Great Depression and the high structural unemployment throughout the interwar period. Early in the 1920s, matching efficiency improved due to the development of the retail industry. However, the econometric results show a structural break in March 1927, related to a major industrial reshuffling that reduced the demand for workers in staple industries. Since these industries were geographically concentrated, there was an increase in the average distance between the unemployed and vacancies, and matching efficiency declined

Workers and militant labour activists from Punjab in Bengal (1921-1934)

Sikh migrants joined post-war strike-waves, formed unions and turned left in the 1920s and early 1930s in and around Calcutta, in the South Bengal region under British rule. To them, an unofficial commemoration of Komagata Maru’s voyage and the militancy associated with the Ghadar movement during First World War, became inseparable from contemporary resistance to the domination of colonial capital and British colonial state in India. They engaged with, worked upon and simultaneously moved beyond the boundaries of ethno-linguistic and religious identities as well as the social content of anti-colonial nationalism by focusing on a self-aware identity based on organised class action. This understanding was linked with the lived experiences of migration and imperial exploitation, the components of identity that had come to the forefront during the war. The diasporic identity of the Sikh migrant workers converged with the wider labour movement and was politically reshaped in the post-war context as livelihood issues took on the form of systematic protests in the city and beyond

Some new efficient multipoint iterative methods for solving nonlinear systems of equations

It is attempted to put forward a new multipoint iterative method of sixth-order convergence for approximating solutions of nonlinear systems of equations. It requires the evaluation of two vector-function and two Jacobian matrices per iteration. Furthermore, we use it as a predictor to derive a general multipoint method. Convergence error analysis, estimating computational complexity, numerical implementation and comparisons are given to verify applicability and validity for the proposed methods.This research was supported by Islamic Azad University - Hamedan Branch, Ministerio de Ciencia y Tecnologia MTM2011-28636-C02-02 and Universitat Politecnica de Valencia SP20120474.Lotfi, T.; Bakhtiari, P.; Cordero Barbero, A.; Mahdiani, K.; Torregrosa Sánchez, JR. (2015). Some new efficient multipoint iterative methods for solving nonlinear systems of equations. International Journal of Computer Mathematics. 92(9):1921-1934. https://doi.org/10.1080/00207160.2014.946412S1921193492

Health policy under self-government 1921-1934

'Owing perhaps to Malta's role as a fortress in the Mediterranean very little attention seems to have been given to its Medical and Health History’. By the First World War, Malta was again to play the role of nurse in the Mediterranean. This was certainly not the first time. At the time of the Hospitallers, Malta was not only used to fight the infidel but, with the Knights' Sacra Infermeria also to provide comfort and shelter for the sick and wounded. As a result of the Crimean war when Turkey joined the Central-Powers and it became necessary for the Allies to attack the Gallipoli Peninsula and the Dardanelles, Malta was also called upon to house the sick and the wounded. The Maltese rose to the occasion and housed and gave assistance to hundreds of men. Even schools were turned into hospitals.peer-reviewe

To Adjust or Not to Adjust? Sensitivity Analysis of M-Bias and Butterfly-Bias

"M-Bias," as it is called in the epidemiologic literature, is the bias introduced by conditioning on a pretreatment covariate due to a particular "M-Structure" between two latent factors, an observed treatment, an outcome, and a "collider." This potential source of bias, which can occur even when the treatment and the outcome are not confounded, has been a source of considerable controversy. We here present formulae for identifying under which circumstances biases are inflated or reduced. In particular, we show that the magnitude of M-Bias in linear structural equation models tends to be relatively small compared to confounding bias, suggesting that it is generally not a serious concern in many applied settings. These theoretical results are consistent with recent empirical findings from simulation studies. We also generalize the M-Bias setting (1) to allow for the correlation between the latent factors to be nonzero, and (2) to allow for the collider to be a confounder between the treatment and the outcome. These results demonstrate that mild deviations from the M-Structure tend to increase confounding bias more rapidly than M-Bias, suggesting that choosing to condition on any given covariate is generally the superior choice. As an application, we re-examine a controversial example between Professors Donald Rubin and Judea Pearl.Comment: Journal of Causal Inference 201

'Sur le front...des missions': French-Canadian missionaries in the Japanese empire, 1921-1934

The late 1920s and early 1930s was a period of violent political and military upheaval in Japan and Northern China, a simmering powederkeg which finally exploded in the Manchurian Crisis of 1931-32. In the early 1930s, there were around 80 French-Canadians Catholic missionaries living in Japan and Japanese-held territory. In Manchuria, French-Canadian missionaries were in the middle of a war-zone, while in Japan, an increasingly militaristic government kept missionaries under closer supervision. Despite some recent publications on the work of French-Canadian missionaries in Japan and China, there is still a rather incomplete picture of their experience in this turbulent period. Through recently discovered first-hand accounts of French-Canadian missionaries published in the Montreal newspaper, Le Devoir, this paper reveals their representation of the Japanese and Chinese in the Japanese Empire in times of war and peace.Not peer reviewe

Time-optimal Control Strategies for Electric Race Cars with Different Transmission Technologies

This paper presents models and optimization methods to rapidly compute the achievable lap time of a race car equipped with a battery electric powertrain. Specifically, we first derive a quasi-convex model of the electric powertrain, including the battery, the electric machine, and two transmission technologies: a single-speed fixed gear and a continuously variable transmission (CVT). Second, assuming an expert driver, we formulate the time-optimal control problem for a given driving path and solve it using an iterative convex optimization algorithm. Finally, we showcase our framework by comparing the performance achievable with a single-speed transmission and a CVT on the Le Mans track. Our results show that a CVT can balance its lower efficiency and higher weight with a higher-efficiency and more aggressive motor operation, and significantly outperform a fixed single-gear transmission.Comment: 5 pages, 4 figures, submitted to the 2020 IEEE Vehicle Power and Propulsion Conferenc

Minimum Race-Time Planning-Strategy for an Autonomous Electric Racecar

Increasing attention to autonomous passenger vehicles has also attracted interest in an autonomous racing series. Because of this, platforms such as Roborace and the Indy Autonomous Challenge are currently evolving. Electric racecars face the challenge of a limited amount of stored energy within their batteries. Furthermore, the thermodynamical influence of an all-electric powertrain on the race performance is crucial. Severe damage can occur to the powertrain components when thermally overstressed. In this work we present a race-time minimal control strategy deduced from an Optimal Control Problem (OCP) that is transcribed into a Nonlinear Problem (NLP). Its optimization variables stem from the driving dynamics as well as from a thermodynamical description of the electric powertrain. We deduce the necessary first-order Ordinary Differential Equations (ODE)s and form simplified loss models for the implementation within the numerical optimization. The significant influence of the powertrain behavior on the race strategy is shown.Comment: Accepted at The 23rd IEEE International Conference on Intelligent Transportation Systems, September 20 - 23, 202

Half-trek criterion for generic identifiability of linear structural equation models

A linear structural equation model relates random variables of interest and corresponding Gaussian noise terms via a linear equation system. Each such model can be represented by a mixed graph in which directed edges encode the linear equations and bidirected edges indicate possible correlations among noise terms. We study parameter identifiability in these models, that is, we ask for conditions that ensure that the edge coefficients and correlations appearing in a linear structural equation model can be uniquely recovered from the covariance matrix of the associated distribution. We treat the case of generic identifiability, where unique recovery is possible for almost every choice of parameters. We give a new graphical condition that is sufficient for generic identifiability and can be verified in time that is polynomial in the size of the graph. It improves criteria from prior work and does not require the directed part of the graph to be acyclic. We also develop a related necessary condition and examine the "gap" between sufficient and necessary conditions through simulations on graphs with 25 or 50 nodes, as well as exhaustive algebraic computations for graphs with up to five nodes.Comment: Published in at http://dx.doi.org/10.1214/12-AOS1012 the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org