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Fighter pilots must study models of aircraft dynamics before learning complex maneuvers and tactics. Similarly, autonomous fighter aircraft applications may benefit from a model-based learning approach. Instead of using a preexisting physics model of a given aircraft, a machine learning system can learn a predictive model of the aircraft physics from training data. Furthermore, it can model interactions between multiple friendly aircraft, enemy aircraft, and the environment. Such a system can also learn to represent state variables that are not directly observable, as well as dynamics that are not hard coded. Existing model-based methods use a deep neural network that takes observable state information and agent actions as input and provides predictions of future observations as output. The proposed method builds upon this approach by adding a residual feedforward skip connection from some of the inputs to all of the outputs of the deep neural network. Further innovations address numerical conditioning issues as well as periodic discontinuities of angular quantities such as bearing or heading. The methods in this article also extend techniques from model-based reinforcement learning control to the domain of adversarial multi-agent environments. In previous literature, these model-based methods have only been used for controlling individual agents. Instead of using a traditional Recurrent Neural Network (RNN) to learn a representation of the world state, the novel method also uses a compressive encoding scheme. This is based on an augmented version of the same neural network that is used for predictive modeling.

There appears a linear relationship between small increases in running speed and cardiovascular health benefits. Encouraging or coaching recreational runners to increase their running speed to derive these health benefits might be more effective if their joint level kinematic and kinetic strategy was understood. The aim of this investigation was to compare the peak sagittal plane motions, moments, and powers of the hip, knee and ankle at 85%, 100%, 115% and 130% of self-selected running speed. Overground running data were collected in 12 recreational runners (6 women, 6 men) with a full body marker set using a 12-camera Vicon MX system with an AMTI force plate. Kinematics and kinetics were analyzed with Vicon Nexus software. Participants chose to run at 2.6 ± 0.5 m/s (85%); 3.0 ± 0.5 m/s (100%); 3.3 ± 0.5 m/s (115%); and 3.7 ± 0.5 m/s (130%); these four speeds approximately correspond to 6:24-, 5:33-, 5:03-, and 4:30-min kilometer running paces. Running speed had a significant effect (P < 0.05) on peak kinematic and kinetic variables of the hips, knees and ankles, with peak sagittal hip moments invariant (P > 0.54) and the peak sagittal ankle power generation (P < 0.0001) the most highly responsive variable. The timing of the peak sagittal extensor moments and powers at the hip, knee and ankle were distributed across stance in a sequential manner. This study shows that running speed affects lower limb joint kinematics and kinetics and suggests that specific intersegmental kinetic strategies might exist across the narrow range of running speeds.

In a panel discussion, professors discussed economic integration and the future of the nation-state. Ken Arrow of Stanford University stated that the definition of a state in great part has to do with its relations with other states. Similarly, nations get their differentiation by cultural identity. Nations are created in part by state action. Charles Wolf of RAND Corp. said that forces impacting the nation-state relate essentially to the reduced and decreasing costs of information, communication, and transportation. Contacts and transactions increasingly will involve the international arena and players other than the nation-state. Michael D. Intriligator of the University of California stated that since 1989, Central and Eastern Europe have experienced a sequence of revolutions. After some 40 years of a dynamic economic integration process, particularly in Europe, this process may be coming to an end, due to the emergence of a new process - disintegration.

The annual election for officers and members of the Council of the American Political Science Association took place between November 2 and 23, 1970, with results reported in the Winter, 1971, issue of this journal. Voting was for one President-elect, three Vice Presidents, one Secretary, one Treasurer and eight members of the Council. There were two candidates each for President-elect, Secretary and Treasurer, five for Vice President and sixteen for Council. These candidates were nominated and supported by a variety of groups and three of these groups—The American Political Science Association nominating committee, the Ad Hoc Committee and the Caucus for a New Political Science—fielded complete or virtually complete slates. This report is an analysis of some of the patterns in the voting. We have worked with constraints, however. Since we received only ballots for the candidates, we were unable to analyze voting on constitutional amendments and resolutions or to look at candidate voting patterns in conjunction with voting patterns on issues. Secondly, there was the limitation inherent in any secret ballot; it was not possible directly to relate voting patterns to attributes of the voters. Thirdly, we did not receive the ballots until early April, 1971. Carding and analyzing them took so much time that we were not able to do all that we had planned. Thus this article is a great deal less comprehensive than we would have liked.

The annual election for officers and members of the Council of the American Political Science Association took place between November 2 and 23, 1970, with results reported in the Winter, 1971, issue of this journal. Voting was for one President-elect, three Vice Presidents, one Secretary, one Treasurer and eight members of the Council. There were two candidates each for President-elect, Secretary and Treasurer, five for Vice President and sixteen for Council. These candidates were nominated and supported by a variety of groups and three of these groups—The American Political Science Association nominating committee, the Ad Hoc Committee and the Caucus for a New Political Science—fielded complete or virtually complete slates. This report is an analysis of some of the patterns in the voting. We have worked with constraints, however. Since we received only ballots for the candidates, we were unable to analyze voting on constitutional amendments and resolutions or to look at candidate voting patterns in conjunction with voting patterns on issues. Secondly, there was the limitation inherent in any secret ballot; it was not possible directly to relate voting patterns to attributes of the voters. Thirdly, we did not receive the ballots until early April, 1971. Carding and analyzing them took so much time that we were not able to do all that we had planned. Thus this article is a great deal less comprehensive than we would have liked.