A Neuro-computational Account of Arbitration between Choice Imitation and Goal Emulation during Human Observational Learning

When individuals learn from observing the behavior of others, they deploy at least two distinct strategies. Choice imitation involves repeating other agents’ previous actions, whereas emulation proceeds from inferring their goals and intentions. Despite the prevalence of observational learning in humans and other social animals, a fundamental question remains unaddressed: how does the brain decide which strategy to use in a given situation? In two fMRI studies (the second a pre-registered replication of the first), we identify a neuro-computational mechanism underlying arbitration between choice imitation and goal emulation. Computational modeling, combined with a behavioral task that dissociated the two strategies, revealed that control over behavior was adaptively and dynamically weighted toward the most reliable strategy. Emulation reliability, the model’s arbitration signal, was represented in the ventrolateral prefrontal cortex, temporoparietal junction, and rostral cingulate cortex. Our replicated findings illuminate the computations by which the brain decides to imitate or emulate others

F-35 and military spending

How does the F-35 Lightning II multirole fighter compare to current military airplanes in terms of costs and capabilities? This is a comparison study based around the F-35 and five other planes. The F-35 is chosen because of its status as an ongoing project and due to its controversy as a plane. This study looks at all values. It is completely numeric based allowing for objective analysis. These planes chosen for study are the F-16 C/D, F/A-18 E/F, F-22A, AV-8B Harrier II, and A-10C. These planes are chosen because the F-35 is meant to replace them in the case of all the planes except the F-22A.In the case of the F-22A, it is the same generation as the F-35 and developed a bit earlier. In conducting the research on the F-35 it is found that while comparing cost data to capabilities the F-35 is not worth the money spent when compared to modern platforms

Faculty and Administrators Working Together in a Community College: A Retrospective Case Study

Community colleges are facing many large-scale problems, such as increased accountability, in a time of shrinking budgets and students who are often unprepared for college level work. The implications of these problems to institutions that are striving to maintain access to higher education for vulnerable populations are grave. These problems, and others, require creative solutions that involve numerous individuals and groups across the institution. The purpose of this retrospective case study was to learn how faculty and administrators experienced collaboration in the context of a community college. The study was carried out at Southern Maine Community College (SMCC) in South Portland, Maine by studying a two-year long attempt at collaboration between faculty and administrators. Data were collected through a combination of interviews with six participants, followed by a focus group of five of these participants, document collection, and participant observation. Through an iterative process (Miles & Huberman, 1994), data were subjected to open coding and then focused coding with codes drawn from the literature using the program HyperResearch. Analysis was undertaken utilizing matrices and concept maps to uncover patterns and significant instances. Collaboration and its relationship to cooperation played an important role in the study. Clearly defining collaboration and cooperation lead to identification of two distinct groups within the participants. The implications for future practice in this study were found in three specific areas: (1) collaborative capacity in a community college setting; (2) topics appropriate for collaborative methods; and (3) viewing collaboration as a dance between collaborators and cooperators. To build collaborative capacity requires a foundation of trust that is, in part, built and maintained through successive collaborative endeavors. Every attempt at collaboration is an opportunity to build trust and create connections between groups and individuals that can be used to aid future collaborations. The topic of the attempted collaboration should be one that promotes interaction among participants -- preferably a topic with which many in the community are already concerned. Envisioning intra-organizational collaboration as a dance between collaborators and cooperators helps to make the needs of both groups explicit

A Review of Energy Models. No. 3 (Special Issue on Soviet Models)

The experience of the USSR in the field of energy systems development modeling reveals certain patterns and principles that influence the structure and use of energy models, principally: -- The need to use mainly optimization models since, for planning purposes, optimal solutions must be found; -- The need to coordinate individual models in order to obtain the country's objectives; -- The existing organizational structure of planning which must be taken into account; -- The dependence of models on time aspects of planning (annual, 5-year, 15-year); -- The elaboration of corresponding methods for providing necessary input data. This has required the development of a special concept for optimizing energy systems development with the use of mathematical models. It is based on consideration of the energy industries of the country as complex with a hierarchical structure of energy systems of various territorial and branch levels. At the same time, the differentiation of aims at different times during the planning period have been taken into account. This concept is given here in its existing state (it is continuously developed and perfected) for better understanding of the energy models described. In particular, we show the role of the system of models for optimization of the energy supply system as a whole, and that of more detailed branch models (oil, gas, coal, electricity production systems). For optimal energy strategy evaluation, the most important models are those used on the highest levels of the energy systems hierarchy, i.e. the general (aggregate) energy systems of the country and of economic regions, and branch energy systems. Only these models are described here; models used on lower levels for solving some technical problems are far more diverse and numerous, and it is impossible to consider them all in a single review

A Review of Energy Models No.4 - July 1978

This review is the fourth in the IIASA series A REVIEW OF ENERGY MODELS (RR-74-10, No. 1 of May 1974 as revised in September 1976; RR-75-30, No. 2 of July 1975; and RR-77-13, No. 3, Special Issue of Soviet Models), which aims at wider diffusion of energy modeling work in progress at other institutions. Fourteen models are described in this issue and again classified in terms of substance and geographical applicability with further subdivision into groups corresponding to model user requirements: the majority of the models focus on the energy problem; they are mostly national ones involving either one or several kinds of fuel; six other models, both international and national, combine energy and overall economic aspects; they may be of particular interest for a more global consideration of energy problems

Simulation Application for the LHCb Experiment

We describe the LHCb detector simulation application (Gauss) based on the Geant4 toolkit. The application is built using the Gaudi software framework, which is used for all event-processing applications in the LHCb experiment. The existence of an underlying framework allows several common basic services such as persistency, interactivity, as well as detector geometry description or particle data to be shared between simulation, reconstruction and analysis applications. The main benefits of such common services are coherence between different event-processing stages as well as reduced development effort. The interfacing to Geant4 toolkit is realized through a facade (GiGa) which minimizes the coupling to the simulation engine and provides a set of abstract interfaces for configuration and event-by-event communication. The Gauss application is composed of three main blocks, i.e. event generation, detector response simulation and digitization which reflect the different stages performed during the simulation job. We describe the overall design as well as the details of Gauss application with a special emphasis on the configuration and control of the underlying simulation engine. We also briefly mention the validation strategy and the planing for the LHCb experiment simulation.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics (CHEP03), La Jolla, Ca, USA, March 2003, 6 pages, LaTeX, 9 eps figures. PSN TUMT00

Réduction et contrôle du foisonnement filamenteux des boues activées par application d'un régime turbulent

Le foisonnement filamenteux des boues activées est un problème important dans les stations d'épuration du type Boues Activées, car il peut entraîner des pertes de biomasse avec l'eau épurée. Les techniques de lutte utilisées actuellement sont, soit des techniques dites « biologiques » (sélecteurs), soit des techniques chimiques (floculants, biocides). L'objectif de notre travail a été la mise au point d'un procédé original basé sur la création d'une zone de turbulence pour casser les réseaux filamenteux. La réduction et le contrôle du bulking sont obtenus par passage (de durée limitée T1) de la biomasse dans un système venturi, équipée d'une prise d'air. L'efficacité du procédé dépend principalement de la turbulence due à l'auto-aspiration d'air au niveau du rétrécissement du venturi. Cette turbulence contribue d'une part au mécanisme de « cisaillement » des filaments, et d'autre part à la qualité de l'effluent sortant. Une gestion adaptée (aération séquentielle en procédé à faible charge) permet d'obtenir, outre une amélioration de la décantation, une amélioration de l'élimination de l'azote. De plus, le contrôle de la biomasse optimise l'élimination de la pollution carbonée.The loss of biomass in a waste water plant as a result of sludge bulking is an important problem. Biological (ex.: selector configuration) or chemical (ex. : floculating reagents, biocides...) methods habe been used in order to control bulking. A new process based on the generation of turbulence to break the filaments is described. To reduce and control sludge bulking, the biomass is pumped through a venturi equipped with an air inlet. Figure 1 represents the pilot scheme. Two processes can be used : the emulsor with air is introduced on recycling of sludge or is placed in an independent loop. Here, it is the latter that has been used.We tried to reduce bulking by mechanical treatment. The hydrodynamic efficiency of the process depends mostly on the degree of turbulence generated by the waters speed and by the suction of air in the constricted part of the venturi.During the first trials on the plant, we defined the maximum turbulence allowed in order not to break the floc. We could not use a big aeration to prevent defloculation.The main factors to reduce bulking are :- the sequences of usage of the emulsor venturi (the periodicity of the treatment is T),- the speed of the water in the nozzle of the venturi (we can refer to the Reynolds Number Re = Ud/ʋ; but this number can’t really represent the turbulence created),- the duration of the emulsor's application. The emulsor venturi is used during a period T1 with a periodicity T (T>T1), with T1 : n X (VR/qv) where VR/qv is the contact time in the venturi and n is the frequence of recycling.During the period T, it is possible to use continuous aeration or to work with sequential aeration.a) continuous aeration|_________________________| TTime between two applications of the venturi|_______________| T1Venturi durationThe process is the same as the aeration of activated sludge. COD is reduced but only with low load, significant nitrification occurs. Figure 5 shows the efficiency of the continuous aeration process especially versus the sludge index parameter.b) sequential aerationAs we try to remove nitrogen, the sequential aeration is more useful than continuous aeration. A cycle is divided in two periods (T2, T3 with T = T2 + T3), and of course, the duration of the venturi use equal to T1.|_________________________| TTime between two applications of the venturi|_____________| T1Venturi duration|_________________| T2Aeration duration          |_____| T3Anoxic periodFigures 6 and 7 show the efficiency of the emulsor if we consider lB (sludge index) as the main parameter for the sequential operation (T2, T3) and it's also possible to obtain a good removal of nitrogen pollution.Our operations parameters were for these experiments :T = 8 or 12 hoursT1 between 20 min. and 1 hourT2 between 4 and 5 hoursThis process is now patiented and the first industrial applications are now defined

Study of Ironless Permanent Magnet Devices Being Both a Coupling and an Axial Bearing for Naval Propulsion

This paper describes the study of an original permanent magnet device. This device works as both a coupling and as axial bearing. It can be particularly useful in naval propulsion application to transmit the torque without any contact between a motor axis and the propeller and to maintain the propeller in its axial position, compensating the axial force related to thrust. Two kinds of devices are studied for this type of specification. The first corresponds to the classical structure of cylindrical air-gap coupling. The second is an original structure where pairs of rings of axially magnetized magnets are stacked on each rotor. The computation of the behavior of the device (torque and axial force) is done using a semi-analytical method based on magnetic charge theory. This method allows a very fast calculation of the performances of the devices. This study shows the interest of the stacked structure this type of application