Exact solutions of an extended Bose-Hubbard model with E2 symmetry

An extended Bose-Hubbard (BH) model with number-dependent multi-site and infinite-range hopping is proposed, which, similar to the original BH model, describes a phase transition between the delocalized super-fluid (SF) phase and localized Mott insulator (MI) phase. It is shown that this extended model with local Euclidean E2 symmetry is exactly solvable when on-site local potential or disorder is included, while the model without local potential or disorder is quasi-exactly solvable, which means only a part of the excited states including the ground state being exactly solvable. As applications of the exact solution for the ground state, phase diagram of the model in 1D without local potential and on-site disorder for filling factor rho = 1 with M = 6 sites and that with M = 10 are obtained. The probabilities to detect n particles on a single site, Pn, for n = 0, 1, 2 as functions of the control parameter U/t in these two cases are also calculated. It is shown that the critical point in Pn and in the entanglement measure is away from that of the SF-MI transition determined in the phase analysis. It is also shown that the the model-independent entanglement measure is related with Pn, which, therefore, may be practically useful because Pn is measurable experimentally.Comment: 5 pages, 3 figures, LaTe

Antenna Design with Characteristic Mode Analysis for Internet of Things Applications

PhDThe TV white space (TVWS) is one of the promising technologies to provide wide coverage, energy effcient and cost effective Internet of Things (IoT) services. However, its low operating frequency and wide bandwidth poses significant challenges to antenna designs. In this thesis, three antennas are developed using the characteristic mode analysis (CMA) for IoT devices operating over the TVWS. First, a very-low profile circular small antenna is transformed from a vertical monopole antenna. The CMA is used to determine the mode to be excited and to design a specific feeding structure. After being printed on Rogers 5880 substrate, the final antenna structure operates at 474 MHz with a V SWR < 2 bandwidth of 2.2 MHz. Its lateral radius is just 5.2% of the wavelength of its resonant frequency. Second, a compact U-shaped printed UWB monopole antenna is proposed to operate over the entire UHF TV spectrum. This antenna measures 0:36 0 0:06 0 0:01 0 where 0 is the wavelength of its lowest operating frequency. Its V SWR < 2 bandwidth is 87.5%, and the UWB behaviour is discussed by the CMA. Third, a novel antenna design method is established on annular ring-shaped structures with modal characteristics revealed by the CMA. Following the proposed method, another UWB antenna is achieved by creating and exciting multiple modes with resonant frequencies distributed across the UHF TV spectrum. All antenna designs are verified thorough simulations and measurements. Furthermore, antennas are also integrated into IoT devices and their system performance is measured under different communication scenarios. The system measurements also verify the good propagation property and the abundant spectrum resource of the TVWS

The Impact of Liquid Droplets on Granular Media

This research was supported by the Undergraduate Research Opportunities Program (UROP)

Blind spheres of paramagnetic dopants in solid state NMR

Solid-state NMR on paramagnetically doped crystal structures gives information about the spatial distribution of dopants in the host. Paramagnetic dopants may render NMR active nuclei virtually invisible by relaxation, paramagnetic broadening or shielding. In this contribution blind sphere radii r(0) have been reported, which could be extracted through fitting the NMR signal visibility function f (x) = exp(-ar(0)(3)x) to experimental data obtained on several model compound series: La(1-x)Ln(x)PO(4) (Ln = Nd, Sm, Gd, Dy, Ho, Er, Tm, Yb), Sr1-xEuxGa2S4 and (Zn1-xMnx)(3)(PO4)(2)center dot 4H(2)O. Radii were extracted for H-1, P-31 and Ga-71, and dopants like Nd3+, Gd3+, Dy3+, Ho3+, Er3+, Tm3+, Yb3+ and Mn2+. The observed radii determined differed in all cases and covered a range from 5.5 to 13.5 angstrom. While these radii were obtained from the amount of invisible NMR signal, we also show how to link the visibility function to lineshape parameters. We show under which conditions empirical correlations of linewidth and doping concentration can be used to extract blind sphere radii from second moment or linewidth parameter data. From the second moment analysis of La1-xSmxPO4 P-31 MAS NMR spectra for example, a blind sphere size of Sm3+ can be determined, even though the visibility function remains close to 100% over the entire doping range. Dependence of the blind sphere radius r(0) on the NMR isotope and on the paramagnetic dopant could be suggested and verified: for different nuclei, r(0) shows a 3 root gamma-dependence, gamma being the gyromagnetic ratio. The blind sphere radii r(0) for different paramagnetic dopants in a lanthanide series could be predicted from the pseudo-contact term

Radiation Energy and Mutual Coupling Evaluation for Multimode MIMO Antenna Based on the Theory of Characteristic Mode

This paper presents a novel method to evaluate radiation energy and mutual coupling in multimode antennas. Based on the theory of characteristics mode, how much each mode occupies the radiation and the mutual coupling from each feeding port is calculated with the modal energy occupied coefficients. Furthermore, the linear transformation of feeding network in multimode antenna system has been adopted to complete the modal-based method. Then, this method is utilized to analyze and decrease the mutual coupling between feeding ports. Hence, a hexagonal wideband antenna is proposed with its evolution process and measured to validate the proposed method. The presented hexagonal antenna is a four-port multimode antenna consisting a planar hexagonal plate, vertical tapered baluns, and feeding network at the ground plane. The whole antenna works in 3-6 GHz and all its four ports are well matched with high port-to-port isolation

Effects of Oral Administration of Encapsulated-Leucine on Amino (uji plagiasi)

Background And Objective: An abundantstud showthat leucine (Leu) acts as an anabolic agent that stimulates skeletal musce growth in human as well as in animals. Haver, the effect of encapsulated leucine (CL) supplementation on growth performance of broiler chickens has not been evaluated. Therefore, the aim of this study was to determine intlal metags responses to CL supplementation on food intake plan metabolites and branched chain amino acid concentration in 7-day-old broiler chicks. Materials and Methods: A total of 24 chicks were randomly assigned to the following treatments (1) Control 4 ) (2) Free leucine 4h iDand (3) Encapsulated leucine th (CL). After 6 Fasting, chicks were given a bolus of oral injection of distilled water, freel ne (6 mmol/10 ml.kg - BWor encapsulated-leucine (6 mmol/10 mt kg BW). Immediately after the injection, chicks were allowed free access to a commercialstarter diet for lh Blood collections were obtained after the oral injection Food intake total glucose total cholesterol, triacylglycerol, plasma leucine levels and the activity of glutamic oxaloacetic transaminase(GOT) were marred. Results: Food intake, glucose total cholesterol and triacylglycerol levels were not affected by Supplementation At 4 h, GOT levels were gre p .05)in the group than that were similar in all groups. Valine levels were lower (p<0.005) inthend Cl Groups of the groups At 4 h, although plasma leu os than that of thel.eu group and isoleucine levels were lower (p<0.001) in the group than that of the candle groups. Conclusion: The results of this study suggest that an oral administration of a caused prolonged leucine induced anabolics that may be beneficial for growth Our observations above the way for studying the long temeffects of supplementation performance of broiler chicks

TCN-GAT multivariate load forecasting model based on SHAP value selection strategy in integrated energy system

Load forecasting is an important prerequisite and foundation for ensuring the rational planning and safe operation of integrated energy systems. In view of the interactive coupling problem among multivariate loads, this paper constructs a TCN-GAT multivariate load forecasting model based on SHAP (Shapley Additive Explanation) value selection strategy. The model uses temporal convolutional networks (TCN) to model the multivariate load time series of the integrated energy system, and applies the global attention mechanism (GAT) to process the output of the network hidden layer state, thereby increasing the weight of key features that affect load changes. The input variables are filtered by calculating the SHAP values of each feature, and then returned to the TCN-GAT model for training to obtain multivariate load forecasting results. This can remove the interference of features with low correlation to the model and improve the forecasting effect. The analysis results of practical examples show that compared with other models, the TCN-GAT multivariate load forecasting model based on SHAP value selection strategy proposed in this paper can further reduce the forecasting error and has better forecasting accuracy and application value

A long-term cohort study: the immune evasion and decreasing neutralization dominated the SARS-CoV-2 breakthrough infection

Most of vaccinees and COVID-19 convalescents can build effective anti-SARS-CoV-2 humoral immunity, which helps preventing infection and alleviating symptoms. However, breakthrough viral infections caused by emerging SARS-CoV-2 variants, especially Omicron subvariants, still pose a serious threat to global health. By monitoring the viral infections and the sera neutralization ability of a long-tracked cohort, we found out that the immune evasion of emerging Omicron subvariants and the decreasing neutralization led to the mini-wave of SARS-CoV-2 breakthrough infections. Meanwhile, no significant difference had been found in the infectivity of tested SARS-CoV-2 variants, even though the affinity between human angiotensin-converting enzyme 2 (hACE2) and receptor-binding domain (RBDs) of tested variants showed an increasing trend. Notably, the immune imprinting of inactivated COVID-19 vaccine can be relieved by infections of BA.5.2 and XBB.1.5 variants sequentially. Our data reveal the rising reinfection risk of immune evasion variants like Omicron JN.1 in China, suggesting the importance of booster with updated vaccines

Market investigation of basic parameters for exposure assessment of contact materials for nut-seed food in China

Objective To establish the basic parameters for exposure assessment of contact materials for nut-seed food in China. Methods The contact area method was used to study the contact materials of nut-seed food in this study. Based on the contact area values, ratio of contact areas and unit mass were obtained. Results Through investigation and analysis, 114 kinds of nut-seed food were sampled, and 3 648 related data were obtained. Food contact materials of nut-seed food on the market mainly included aluminum, polyethylene, polyethylene terephthalate, polypropylene, polystyrene and coating. The average contact area per unit mass or volume (S/V) was 21.29 dm2/kg, the median was 13.40 dm2/kg, P5 was 1.11 dm2/kg, and P95 was 67.46 dm2/kg. Conclusion The basic parameters of nut-seed food contact materials could provide data support for the safety assessment in China