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We report a multiple-loop guided atom interferometer in which the atoms make 200 small-amplitude roundtrips, instead of one large single orbit. The approach is enabled by using ultracold 39K gas and a magnetic Feshbach resonance that can tune the s-wave scattering length across zero to significantly reduce the atom loss from cold collisions. This scheme is resilient against noisy environments, achieving 0.9 s interrogation time without any vibration noise isolation or cancellation. A form of quantum lock-in amplification can be used with the device to measure localized potentials with high sensitivity. We used this technique to measure the dynamic polarizability of the 39K ground state at 1064 nm. The interferometer may also be a useful approach to building a compact multiple-loop Sagnac atom interferometer for rotation sensing., Comment: 13 pages, 11 figures

Background: Chinese cabbage of the typical crop in Asia is crucial source of supply containing abundant fibroid materials, minerals. It is required to forecast and diagnose growth by remote sensing (RS), GPS and GIS for precision production management of Chinese cabbage. The objective of this study was to develop model for estimating the growth (Fresh weight, leaf area) with spectral information of Chinese cabbage in multispectral image acquired by using unmanned aerial system depending on vegetation stages. Methods: Chinese cabbage in test field was planted on normal planting period (NP) and two delayed planting periods (DP). Multispectral images of test field were acquired at intervals of 2 weeks in midday by using NIR and red edge camera mounted on UAV. Vegetation index and band ratio was calculated by spectral information of sample extracted by image processing. Simple linear regression analysis was employed to develop model of relationship between the growth and index, ratio. Results: It was developed to two models for accurately estimating the growth because models between NP and DP show different linearity in all vegetation stage. The model using NDVI calculated by NIR and Red bands exhibited lower performance (R2=0.690 and RMSE=868.4g in NP, R2=0.851 and RMSE=285.1g in DP) by saturation of light-sensitivity NIR. The model using ratio between less light-sensitivity Red edge and blue bands in NP exhibited the best performance (R2=0.798, RMSE=700.9g). Also, the models using ratio between Red edge and green bands in DP exhibited the best performance (R2=0.951, RMSE=162.4). Discussions: It is regarded that red edge band has to be used to solve the problem because it was revealed that light-sensitive NIR band is easy to be saturated at intermediate to high weight. Conclusion: It was possible to accurately estimate the growth of Chinese cabbage with ratio of red edge and visible bands depending on vegetation stages.

Background: This research was performed to develop moisture content model for solanaceae seedlings, such as chili pepper and tomato, based on hyperspectral imagery. Methods: After exposing to high temperature, the reflectance of chili (n=45) and tomato (n=45) seedlings were calculated using the hyperspectral imagery, and the moisture content of all seedlings was measured. Then the predicting models for estimating moisture content were developed with PLS­ Regression analysis by using the two factors Results: As a result, the chilli model showed 0.68 of R2, 1.43% of RMSE and 1.61% of RE, which indicate accuracy and precision respectively. The tomato model showed 0.74 of R2 2.77% of RMSE and 3.09% of RE. Combining all samples (n=90), the solanaceae model showed 0.67 of R2 2.53% of RMSE and 1.61% of RE. Finally the full-cross validation showed 0.59 of R2, 2.83% RMSE and 3.17% of RE. Discussions: Accuracy and precision of the tomato model was slightly better than those of the chilli model. This might be affected by widely distributed variation in tomato seedlings. The solanaceae model, which is combined with chilli and tomato, showed lower accuracy than each single model, however, the precision was higher than the tomato model. This is because that tomato samples distribution was located in chilli distribution and this affected the performance better. Finally, it is considered that both models can be significantly used to estimate moisture content, as gradients of trend line are almost same and intersected. Conclusion: It is considered that the accuracy and precision of the estimated models possibly can be improved, if samples are under a lot of stress. The improved models will be utilized as the basis for developing low-priced sensors.

Application of remote sensing and GIS has great potential in crop monitoring and retrospectively can set the strategies and management practices as to maximize yield and grain quality. In this study, UAV remote sensing data were utilized to predict grain protein content. Total images were differentiated into two groups as cloud free and cloud shadowed. On one hand for the cloud free samples, the vegetation index, NDVI derived from the canopy spectral reflectance was significantly correlated to the final grain protein content (R2=0.553, RMSE=0.210%, n=14). On the other hand, for cloud shadowed samples, the result demonstrated that vegetation index, NDVI was significantly correlated to the final grain protein content (R2=0.479, RMSE=0.225%, n=35). Different layers and files were created to manage, store and mapping grain protein using ArcGIS. All test fields at first and then, the NDVI image of each test field was also converted to shape file. Henceforth, the information of each field was displayed using overlap function. Therefore, protein content of rice in each field can be mapping by GIS and possibly forecasted using canopy or images spectral reflectance at grain filling stage.

Background: This research was conducted to develop moisture content model and estimate its performance in cucurbitaceae seedlings, such as cucumber and water melon, using hyperspectral imagery. Methods: Using a hyperspectral image acquisition system, reflectance of leaf area of cucumber (n=45) and watermelon (n=45) seedlings was calculated after providing water stress. Then, moisture content in each seedling was measured by using a dry oven. Finally, the moisture content estimation models were developed by PLS-Regression analysis with reflectance data and moisture content data. Results: After developing the estimation models, the cucumber model predicts that performance is significant as 0.73 of R2, 1.45% of RMSE, and 1.58% of RE. The watermelon model predicts that performance is acceptable as 0.66 of R2, 1.06% of RMSE, and 1.14% of RE. The model performed slightly better after removing one sample from cucumber seedlings as outlier and unnecessary. Hence, the performance of new model for cucumber seedlings (n=44) showed 0.79 of R2, 1.10% of RMSE, and 1.20% of RE. The model performance combined with all samples (n=89) showed 0.67 of R2, 1.26% of RMSE, and 1.36% of RE. Discussion: The model of cucumber showed better performance than the model of water melon. This is because variables of cucumber are consisted of widely distributed variation, and it affected the performance. Further, accuracy and precision of the cucumber model were increased when an insignificant sample was eliminated from the dataset. Finally, it is considered that both models can be significantly used to estimate moisture content, as gradients of trend line are almost same and intersected. Conclusion: It is considered that the accuracy and precision of the estimating models possibly can be improved, if the models are constructed by using variables with widely distributed variation. The improved models will be utilized as the basis for developing low-priced sensors.

Background: Hyperspectral camera is useful for finding a wavelength range that can estimate growth by using wide spectrum (400-1000nm) ranges. It is possible to apply precision agriculture through determination of accurate harvest season, amount of applied fertilizer and so on according to estimation of growth. The objective of this study was to estimate the growth for radish by using hyperspectral image depending on vegetation stages. Methods: Hyperspectral images of Radish and Chinese cabbage were acquired at intervals of 2 weeks in midday. It was divided into the crop and background area in image by using NDVI and the reflectance values of crop area were calibrated by the values of reference board in same image. PLSR analysis was employed to develop model for estimating growth of the crops with the all spectral band of all vegetation stages. The models for estimating the weight of the crops were evaluated through R 2 and root mean square error (RMSE), which were verified as validation model by full-cross validation. Results: The model for estimating the fresh weight for Radish exhibited high performance (R2=0.950, RMSE=236.3g), but validation model exhibited high error value (R2=0.806, RMSE=492.3g). Likewise, the model for estimating the dry weight exhibited high performance (R2=0.975, RMSE=3.413g), but validation model exhibited high RMSE (R2=0.843, RMSE=8.993g). The model for estimating the fresh weight for Chinese cabbage exhibited high R2 (R2=0.897, RMSE=571.1g), but estimation and validation model exhibited high error value (R2=0.859, RMSE=685.0g). Discussions: The estimation and validation model of the fresh and dry weight for the crops are required to improve RMSE by using different statistics analysis and various vegetation indices. Also, comparative analysis between spectral attributes of this experiment and repeated experiment are required. Conclusion: It is possible to mostly estimate growth of the crops, but estimation and validation models of weight are needed to improve RMSE.

Bessel beams are plane waves with amplitude profiles described by Bessel functions. They are important because of their property of limited diffraction and their capacity to carry orbital angular momentum. Here we report the creation of a Bessel beam of de Broglie matter waves. The Bessel beam is produced by the free evolution of a thin toroidal atomic Bose-Einstein condensate (BEC) which has been set into rotational motion. By attempting to stir it at different rotation rates, we show that the toroidal BEC can only be made to rotate at discrete, equally-spaced frequencies, demonstrating that circulation is quantized in atomic BECs. The method used here to generate matter wave Bessel beams with a Painted Potential can be viewed as a form of wavefunction engineering which might be extended to implement arbitrary cold atom matter wave holography.

It has recently been demonstrated that quantum degenerate gases of very weakly bound molecules can be produced by atomic gases with Feshbach resonances. More strongly bound molecules can be produced with Raman photoassociation of a quantum gas, although this process has not yet been shown to produce a quantum degenerate molecular gas. In principle, Feshbach resonance and Raman photoassociation can be quantum-mechanically reversible, and lead to collective coherent phenomena such as Rabi cycling between an atomic and a molecular gas. However, such atom-molecular coherence has only partly been realized experimentally. Effects that may limit coherence include thermalizing elastic collisions, inelastic collisions, spontaneous Raman scattering, and pairing field formation. Here, we demonstrate a method that circumvents these limitations, based on Raman photoassociation of atoms in an optical lattice and driven into a Mott insulator state. We find that the Raman photoassociation transition is resolved into discrete lines corresponding to the quantized lattice site occupancies, and demonstrate that this provides a new method to accurately determine the distribution of site occupancies and the atom-molecule scattering length. Furthermore, we observe a Raman-induced oscillation of the central core of the gas, containing about 30% of the atoms, between an atomic and a molecular gas., Comment: 14 pages, 4 figures

The in-medium mass of a $\thetaplus$, $\mtheta^*$, in cold symmetric nuclear matter is calculated by using the quark-meson coupling model. The $��^+$ is treated as an MIT bag with the quark content $uudd\bar s$. Bag parameters for a free $\thetaplus$ are fixed to reproduce the observed mass of the $\thetaplus$. In doing so, we use three different values of the $s$-quark mass since the mass of the $s$-quark is not well known. As usual, the strengths of the $u$ and $d$ quark couplings to $��$- and $��$-meson fields are determined to fit the nuclear saturation properties. However, the coupling constant $g_��^s$ between the $s$-quark and the $��$-meson cannot be fixed from the saturation properties, and thus we treat $g_��^s$ as a free parameter and investigate how $\mtheta^*$ depends on $g_��^s$. %$\mtheta^*$ is calculated up to 2.5 times the nuclear saturation density, %and we find that We find that $\mtheta^*$ depends significantly on the value of $g_��^s$ but not on the mass of the $s$-quark. Chemical potentials of the $��^+$ and the $K+N$ system are calculated to discuss the decay of a $��^+$ in nuclear matter. We calculate the effective mass of a kaon in nuclear matter in two ways; using the optical potential of $K^-$ in matter and using quark model. By comparing the effective masses calculated from these two methods, we find the magnitude of the real part of the optical potential that is consistent with the usual quark model is about 100 MeV., 16 pages, 4 figures, 3 tables

We report on first evidence of wave activity during neutral beam heating in KSTAR plasmas: 40 kHz magnetic fluctuations with a toroidal mode number of n=1. Our analysis suggests this a beta-induced Alfven eigenmode resonant with the q=1 surface. A kinetic analysis, when coupled with electron temperature measurements from electron cyclotron emission and ion/electron temperature ratios from crystallography, enables calculation of the frequency evolution, which is in agreement with observations. Complementary detailed MHD modelling of the magnetic configuration and wave modes supports the BAE mode conclusion, by locating an n=1 mode separated from the continuum in the core region. Finally, we have computed the threshold to marginal stability for a range of ion temperature profiles. These suggest the BAE can be driven unstable by energetic ions when the ion temperature radial gradient is sufficiently large. Our findings suggest that mode existence could be used as a form of inference for temperature profile consistency in the radial interval of the mode, thereby extending the tools of MHD spectroscopy., 12 pages, 6 figures, submitted to Plasma Physics and Controlled Fusion