Three-body effects, which are effects of three-body force and three-hotly correlation, are introduced into the two-body nuclear force in a semi-phenomenological way to reproduce the nuclear saturation over all nuclei by the lowest order Brueckner theory. On the hasis of the reaction matrix calculation of nuclear matter with this two-body force including the three· body effects, a new effective potential is proposed which includes two independent parameters, namely, nuclear density and starting-energy. Because of the effect of three-body force, this effective potential is more attractive in the 'E state, compared with the usual one, and assures overall saturation without any artificial modification. The starting-energy dependence of the effective potential is also strengthened by the three-body force. The starting-energy dependence is found to work well for nuclear saturation together with the density dependence. Present density dependence is weaker than that of the usual clensity dependent effective potentials. The effective potential is decomposed into central, spin-orbit and tensor components. § I. IntroductionOn the basis of the realistic nuclear force, properties of nuclear matter and finite nuclei have been investigated and fruitful successes are accumulated. 1 l In particular, the Density-Dependent Hartree-Fock method (DDHF) has yielded remarkably good results for binding energies, density distributions, single particle energies and compressibilities of some finite nuclei.'J However, it should be noted that effective potentials used in DDHF are artificially adjusted by arbitrary factors to reproduce the nuclear saturation. This would be a weak point of DDHF to be investigated.In the reaction matrix theory, 3 l realistic two-body forces ensure about 10"'"' 12MeV I A for the binding energy of nuclear matter, while the empirical value is 16 MeV I A. It is also known from many calculations that with only the two-body force we could not reproduce the empirical binding energy and saturation density simultaneously.") Tamagaki 5 l pointed out this fact and Coester et al. 6 l showed that sufficient binding energy would be obtained only at too high equilibrium density as far as we use two-body forces. Thus it is necessary to seek for some origins which give an additional binding and shift the equilibrium density to the empirical one. Two of the present authors (T.K. and Y.A.) and co-vvorkersn.sJ have pointed at University of British Columbia on June 18, 2015 http://ptp.oxfordjournals.org/ Downloaded from

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Unmanned aerial vehicles (UAVs or drones) are a very promising branch of technology, and they have been utilized in agriculture—in cooperation with image processing technologies—for phenotyping and vigor diagnosis. One of the problems in the utilization of UAVs for agricultural purposes is the limitation in flight time. It is necessary to fly at a high altitude to capture the maximum number of plants in the limited time available, but this reduces the spatial resolution of the captured images. In this study, we applied a super-resolution method to the low-resolution images of tomato diseases to recover detailed appearances, such as lesions on plant organs. We also conducted disease classification using high-resolution, low-resolution, and super-resolution images to evaluate the effectiveness of super-resolution methods in disease classification. Our results indicated that the super-resolution method outperformed conventional image scaling methods in spatial resolution enhancement of tomato disease images. The results of disease classification showed that the accuracy attained was also better by a large margin with super-resolution images than with low-resolution images. These results indicated that our approach not only recovered the information lost in low-resolution images, but also exerted a beneficial influence on further image analysis. The proposed approach will accelerate image-based phenotyping and vigor diagnosis in the field, because it not only saves time to capture images of a crop in a cultivation field but also secures the accuracy of these images for further analysis.

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The measurement of air temperature is strongly influenced by environmental factors such as solar radiation, humidity, wind speed and rainfall. This is problematic in low-cost air temperature sensors, which lack a radiation shield or a forced aspiration system, exposing them to direct sunlight and condensation. In this study, we developed a machine learning-based calibration method for air temperature measurement by a low-cost sensor. An artificial neural network (ANN) was used to balance the effect of multiple environmental factors on the measurements. Data were collected over 305 days, at three different locations in Japan, and used to evaluate the performance of the approach. Data collected at the same location and at different locations were used for training and testing, and the former was also used for k-fold cross-validation, demonstrating an average improvement in mean absolute error (MAE) from 1.62 to 0.67 by applying our method. Some calibration failures were noted, due to abrupt changes in environmental conditions such as solar radiation or rainfall. The MAE was shown to decrease even when the data collected in different nearby locations were used for training and testing. However, the results also showed that negative effects arose when data obtained from widely-separated locations were used, because of the significant environmental differences between them.

Metallic powders with various thermodynamic stability oxide films (Ag, Cu, and Al powders) were sintered using a pulse electric-current sintering (PECS) process. Behavior of oxide films at powder surfaces and their effect on the sintering properties were investigated. The results showed that the sintering properties of metallic powders in the PECS process were subject to the thermodynamic stability of oxide films at particles surfaces. The oxide films at Ag powder surfaces are decomposed during sintering with the contact region between the particles being metal/metal bond. The oxide films at Cu powder surfaces are mainly broken via loading pressure at a low sintering temperature. At a high sintering temperature, they are mainly dissolved in the parent metal, and the contact regions turn into the direct metal/metal bonding. Excellent sintering properties can be received. The oxide films at Al powder surfaces are very stable, and cannot be decomposed and dissolved, but broken by plastic deformation of particles under loading pressure at experimental temperatures. The interface between particles is partially bonded via the direct metal/metal bonding making it difficult to achieve good sintered properties.