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Alfalfa is critical to global food security, and its data is abundant in the U.S. nationally, but often scarce locally, limiting the potential performance of machine learning (ML) models in predicting alfalfa biomass yields. Training ML models on local-only data results in very low estimation accuracy when the datasets are very small. Therefore, we explore synthesizing non-local data to estimate biomass yields labeled as high, medium, or low. One option to remedy scarce local data is to train models using non-local data; however, this only works about as well as using local data. Therefore, we propose a novel pipeline that trains models using data synthesized from non-local data to estimate local crop yields. Our pipeline, synthesized non-local training (SNLT pronounced like sunlight), achieves a gain of 42.9% accuracy over the best results from regular non-local and local training on our very small target dataset. This pipeline produced the highest accuracy of 85.7% with a decision tree classifier. From these results, we conclude that SNLT can be a useful tool in helping to estimate crop yields with ML. Furthermore, we propose a software application called Predict Your CropS (PYCS pronounced like Pisces) designed to help farmers and researchers estimate and predict crop yields based on pretrained models. [ABSTRACT FROM AUTHOR]

The commemoration of war is almost as old as war itself – and as war has changed so too has its commemoration. This article explores some of the changes, from the emergence of vernacular forms of memorialization to the process by which objects or practices take on commemorative meaning or, alternately, lose that commemorative meaning. Commercialization has had a significant impact on memorialization and so too has the advent of virtual commemoration, especially through social media. It concludes by surveying some of the challenges that historians of war commemoration may face in the Internet age, even in the face of some striking similarities in the nature of war memorialization. [ABSTRACT FROM AUTHOR]

Focuses on the Canadian government's response to Great Britain's shackling of prisoners of war (POW) during the Second World War. Perception of Commonwealth relations in wartime; Incidence of reprisals against POW; Ambivalent attitude towards retaliation against prisoners.

Summary: We report the serendipitous discovery of a map drawn by an army surgeon during the First World War. The map, entitled “Loos 36° NW3,’”was drawn by 24-year-old Captain Alexander Edward MacDonald in fall 1917 and was found in his old surgery textbook. MacDonald’s map depicts the positions of Canadian frontlines and medical units after the Battle of Hill 70. During the battle, Dr. MacDonald tended to the wounded in an aid post that he constructed in a ruined coal mine near the Front. MacDonald would go on to serve with distinction in the Battle of Passchendaele and Canada’s Hundred Days, and he received the Military Cross for gallantry. He maintained a passionate interest in cartography throughout his life and eventually became an authority among map collectors. Artifacts such as MacDonald’s map remind us of the realities of war and the sacrifices of our surgeon predecessors. [ABSTRACT FROM AUTHOR]

A nonaffine discrete-time system represented by the nonlinear autoregressive moving average with eXogenous input (NARMAX) representation with unknown nonlinear system dynamics is considered. An equivalent affinelike representation in terms of the tracking error dynamics is first obtained from the original nonaffine nonlinear discrete-time system so that reinforcement-learning-based near-optimal neural network (NN) controller can be developed. The control scheme consists of two linearly parameterized NNs. One NN is designated as the critic NN, which approximates a predefined long-term cost function, and an action NN is employed to derive a near-optimal control signal for the system to track a desired trajectory while minimizing the cost function simultaneously. The NN weights are tuned online. By using the standard Lyapunov approach, the stability of the closed-loop system is shown. The net result is a supervised actor-critic NN controller scheme which can be applied to a general nonaffine nonlinear discrete-time system without needing the affinelike representation. Simulation results demonstrate satisfactory performance of the controller. [ABSTRACT FROM AUTHOR]

Past research has shown substantial reductions in the oxides of nitrogen (NOx) concentrations by using 10%–25% exhaust gas recirculation (EGR) in spark ignition (SI) engines (see Dudek and Sam, 1989). However, under high EGR levels, the engine exhibits strong cyclic dispersion in heat release which may lead to instability and unsatisfactory performance preventing commercial engines to operate with high EGR levels. A neural net- work (NN)-based output feedback controller is developed to reduce cyclic variation in the heat release under high levels of EGR even when the engine dynamics are unknown by using fuel as the control input. A separate control loop was designed for controlling EGR levels. The stability analysis of the closed-loop system is given and the boundedness of the control input is demonstrated by relaxing separation principle, persistency of excitation condition, certainty equivalence principle, and linear in the unknown parameter assumptions. Online training is used for the adaptive NN and no offline training phase is needed. This online learning feature and model-free approach is used to demonstrate the applicability of the controller on a different engine with minimal effort. Simulation results demonstrate that the cyclic dispersion is reduced significantly using the proposed controller when implemented on an engine model that has been validated experimentally. For a single cylinder research engine fitted with a modem four-valve head (Ricardo engine), experimental results at 15% EGR indicate that cyclic dispersion was reduced 33% by the controller, an improvement of fuel efficiency by 2%, and a 90% drop in NOx from stoichiometric operation without EGR was observed. Moreover, unburned hydrocarbons (uHC) drop by 6% due to NN control as compared to the uncontrolled scenario due to the drop in cyclic dispersion. Similar performance was observed with the controller on a different engine. [ABSTRACT FROM AUTHOR]

Focuses on soldier-novelists and their works. Significance of publishing of war books in 1928 to the emergence of soldier-novelists; Criticism of the falsifications of history in anti-war literature by Canadian veterans; Examination of the claims of the novel "Generals Die in Bed," by Charles Yale Harrison.

Presents several books on history in the Americas. `New World Economies: The World of the Thirteenth Colonies and Early Canada,' by M. Egnal; `The Lord Cornbury Scandal: The Politics of Reputation in British America,' by P. Bonomi; `Merchants and Empire: Trading in Colonial New York,' by C. Matson; `Border Life: Experience and Memory in the Revolutionary Ohio Valley,' E.A. Perkins.

Discusses publications on the history of several countries in the Americas. French Settlements; Canada; United States; Latin America; Caribbean Area.

Discusses the role of Canadian relief agencies in alleviating the plight of prisoners of war during World War II. Results of government attempts to coordinate the efforts of the Canadian Red Cross Society, the War Prisoners' Aid to the YMCA and the Canadian POW Relatives Association; Praise for the provision of Red Cross food parcels.

Presents several books on history about the Americas. `Pierre-Esprit Radisson: coureur de bois et homme du monde,' by M. Fournier; `Americans: A Collision of Histories,' by E. Countryman; `The Cambridge Economic History of the United States: The Colonial Era,' edited by S. L. Engerman and R.E. Gallman; `The Devil's Disciples: Makers of the Salem Witchcraft Trials,' by P.C. Hoffer; `Benjamin Franklin and His Enemies,' by R. Middlekauff.

Discusses the escape tactics employed by prisoners of war in the prison camp, Stalag Luft 3 at Sagan in Silesia, Poland in March 1944. German management and inspection; Security measures in Stalag Luft 3; Digging of tunnels; Securing optimum conditions and the necessary equipment for escape; Success rates of escape attempts.

In this article, the author discusses papers published within the issue including one on the benefits of relationship between military, technology and society, one on using wartime military technology as a springboard to sales in the peacetime civilian economy and one on the commodification of military technology and expertise.