Renormalizability of the nuclear many-body problem with the Skyrme interaction beyond mean field

Phenomenological effective interactions like Skyrme forces are currently used in mean--field calculations in nuclear physics. Mean--field models have strong analogies with the first order of the perturbative many--body problem and the currently used effective interactions are adjusted at the mean--field level. In this work, we analyze the renormalizability of the nuclear many--body problem in the case where the effective Skyrme interaction is employed in its standard form and the perturbative problem is solved up to second order. We focus on symmetric nuclear matter and its equation of state, which can be calculated analytically at this order. It is shown that only by applying specific density dependence and constraints to the interaction parameters could renormalizability be guaranteed in principle. This indicates that the standard Skyrme interaction does not in general lead to a renormalizable theory. For achieving renormalizability, other terms should be added to the interaction and employed perturbatively only at first order.Comment: Revised versio

Modification and Analysis of a Two-Axis Solar Tracking System

Solar tracking is related to moving the solar panels in such a way that its solar panel always points toward the sun which results in maximum output. The goal of this research was to modify and improve a two-axis solar tracking system. The rotation of the module is controlled by a rotational motor and the tilt is controlled by a linear actuator. The motion and direction of these two motors is controlled by an Arduino code which compares the electrical current going through four mini solar collectors (used as sensors) mounted in orthogonal pairs at the top of the PV panel. If a solar collector has a higher current reading, then it is exposed to more sunlight, so the panel is adjusted until all of the mini solar collectors have nearly the same current output, and thus are receiving the same amount of sunlight. Testing of the designed system was performed alongside an identical, stationary solar panel, which allows for a direct comparison between the electrical outputs of the two solar panels.https://digitalworks.union.edu/steinmetz_posters/1011/thumbnail.jp

Data Preprocessing for Machine Learning Modules

Data preprocessing is an essential step when building machine learning solutions. It significantly impacts the success of machine learning modules and the output of these algorithms. Typically, data preprocessing is made-up of data sanitization, feature engineering, normalization, and transformation. This paper outlines the data preprocessing methodology implemented for a data-driven predictive maintenance solution. The above-mentioned project entails acquiring historical electrical data from industrial assets and creating a health index indicating each asset\u27s remaining useful life. This solution is built using machine learning algorithms and requires several data processing steps to increase the solution\u27s accuracy and efficiency. In this project, the preprocessing measures implemented are data sanitization, daylight savings transformation, feature encoding, and data normalization. The purpose and results of each of the above steps are explained to highlight the importance of data preprocessing in machine learning projects

Effects of High Temperature on Fruit Set in Tomatoes Lycopersicon Esculentum

Flower and fruit drop is a great problem to growers in many tomato producing areas. Workers have observed this phenomenon of the loss of flowers or undeveloped fruit and have associated it with heat, moisture, and physiological condition of the plant. In view of the association of carbohydrate level with yield, one phase of this experiment was designed to determine the separate and combined effects of temperature and light on fruit setting. Both normal and abnormal (high) temperatures were used following a dark treatment. This phase of the work was planned for two main purposes. One was the effect of holding transplants in the dark before planting in the field. This might be of significance in areas where abnormally high temperatures follow transplanting. Another reason for this phase of the work was to obtain an indication of the role of light intensity in fruit setting. The feasibility of future work along this ling might be indicate by the results. Seventeen varieties of tomatoes in phase 3 were used in part of the experiment in order to detect varietal differences in regard to ability to set fruit under adverse conditions. Another phase of the work concerned stages of flower development at which abscission is most likely to occur. The author felt that there was a need for further work in determining at which of various stages, before or after fertilization, abscission is most likely to occur. Applications for commercial growing, for the production of commercial hybrids, and for making crosses in the course of tomato breeding could conceivably be made from these findings. That time of pollination in relation to high temperature might have some bearing on fruit set is to be considered

Second--order equation of state with the Skyrme interaction. Cutoff and dimensional regularization with the inclusion of rearrangement terms

We evaluate the second--order (beyond--mean--field) contribution to the equation of state of nuclear matter with the effective Skyrme force and use cutoff and dimensional regularizations to treat the ultraviolet divergence produced by the zero--range character of this interaction. An adjustment of the force parameters is then performed in both cases to remove any double counting generated by the explicit computation of beyond--mean--field corrections with the Skyrme force. In addition, we include at second order the rearrangement terms associated to the density--dependent part of the Skyrme force and discuss their effect. Sets of parameters are proposed to define new effective forces which are specially designed for second--order calculations in nuclear matter.Comment: 29 figures, 9 table

Second-order equation of state with the full Skyrme interaction: toward new effective interactions for beyond mean-field models

In a quantum Fermi system the energy per particle calculated at the second order beyond the mean-field approximation diverges if a zero-range interaction is employed. We have previously analyzed this problem in symmetric nuclear matter by using a simplified nuclear Skyrme interaction, and proposed a strategy to treat such a divergence. In the present work, we extend the same strategy to the case of the full nuclear Skyrme interaction. Moreover we show that, in spite of the strong divergence ($\sim$ $\Lambda^5$, where $\Lambda$ is the momentum cutoff) related to the velocity-dependent terms of the interaction, the adopted cutoff regularization can be always simultaneously performed for both symmetric and nuclear matter with different neutron-to-proton ratio. This paves the way to applications to finite nuclei.Comment: 15 figure

The hidden-observer and memory creation

The present study sought to investigate the relation between hidden-observer reports and pseudomemory. The study also investigated the rates of hidden-observer responses in age regression. During the screening session subjects were tested on (a) the Tellegen absorption scale (Tellegen, 1980, 1982), (b) The imagery scale of Paivo and Harshman's (1983), Individual Differences Questionnaire, (c) the Autobiographical Memory Questionnaire (Conway, 1994), (d) The Harvard Group Scale of Hypnotic Susceptibility, Form A of Shor and E. Orne (1962). Two experimental groups with different instructions about memory and a control group, participated in a further session to measure their responses to a memory creation item, and to assess the rates of hidden-observer responding. Consistent with previous literature both the phenomenon of memory creation and an increase in confidence in these memories were demonstrated. Memory strength was found not relevant to memory creation. The factors that predicted memory creation were hypnotizability, duality, and cognitive effort. A schema-model was presented to explain the results of this study. Rates of hidden-observer reports by low and medium hypnotizables emphasized the importance of both individual and contextual variables for producing a hidden-observer response. These results were explained as supporting a synergistic model of hypnosis