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We theoretically study dipole-dipole interactions on 3P0-3D1 with ultracold Sr atoms in a deep optical lattice. To prepare such a dense atomic sample, Bose-Einstein condensates (BEC) will be performed and subsequently are loaded into a Mott insulator by increasing the optical potential. Here, we calculate the important properties of Sr dipole-dipole interactions based on the coupled dipole model and also show the setup for the preparation of the Sr sample. Both simulation results and the feasibility of experiments indicate that lattice-based Sr atoms is an excellent candidate for studying dipoledipole interactions.

Localization of unexploded ordnance (UXO) with transient electromagnetic (TEM) system is a principle and necessary problem in detection procedures, especially beset by low data diversity and high positioning uncertainty. In this paper, procedures for targets location are presented in detail with cued data collected by potable TEM sensor JPMD, which is designed to provide diverse time-domain data of high quality with one transmitter coil and five 3-component receiving coils. Based on the single dipole model, the target is located with the data collected at a single spatial point by the differential evolution (DE) optimization algorithm which can be subdivided into three steps. With the structure and parameters of JPMD sensors and data inversion process described briefly, a field test site of 5 m × 5 m measurement grid was conducted to present the specific UXO localization procedures at Jilin University. Results indicate that all the UXO-like targets can be detected distinctly with JPMD. The location of single object can be inversed rapid in tolerable error at one single point. For two objects with overlapping signals as one, the inverted horizontal position is basically in the middle of them and depth is a bit smaller than theory.

In this paper, the transient electromagnetic (TEM) response of an 82mm mortar shell is calculated and measured based on the orthogonal dipole model. The influence of dip angle on target response is analyzed in detail. The theoretical results for time domain response indicate that both the amplitudes and decay rates of the responses change significantly with the dip angle, which means that the time domain response at a certain point is inadequate to identify a target. The z-component of the survey line response is axisymmetric while the x-component is center symmetric. The symmetry of both responses gets worse with the increase of the dip angle. Besides, the symmetric center of x-component and symmetrical axis of z-component will also shift to the right. The measured response agrees well with the calculated one for the low dip angle. If the dip angle reaches 900, the amplitude difference between the calculated and the measured response will be up to 50%, which means the dipole model is no longer suitable.

Noninvasive localization of the foci of premature ventricular contractions (PVCs) was performed in a simulation study using ECGSim software. Single dipole model was used to represent the heart generator and to solve the inverse problem of electrocardiography. Integral body surface potential maps computed from 64 chest leads and inhomogeneous torso model were used as input data for the inverse solution. The accuracy of the PVC localization was evaluated for forty PVC positions located in eight segments in both, right and left ventricle. The mean localization errors of PVC foci in segments of the left ventricle were smaller than for segments in the right ventricle. The best result was achieved for anterior segment of the left ventricle, while the worst one was obtained for the anterior segment in the right ventricle.

Scatter-embedded substrate is a powerful platform for improving light extraction efficiency in OLED lighting. In this work, we propose trans-scale optical simulation for OLEDs involving scattering substrates. This simulation combines rigorous dipole model analyzing thin-film stacks with Monte-Carlo simulation based on Henyey-Greenstein phase function for tracing rays encountered with specific size of scatter. The simulation provides a useful tool to analyze and design OLEDs with bulk scatter.

Magnetic localization systems based on passive permanent magnets (PM) are of great interest due to their ability to provide non-contact sensing and lack of a power requirement of the PM. One sub-problem of particular interest is accurately localizing, in real-time, a single magnetometer with unknown position and orientation, using a passive PM with controllable position and orientation. This is a challenging problem, mainly due to difficulty of designing a magnetic field model that allows high precision localization of a single sensor, but also has other qualities such as low computational complexity and robustness. In this work, we propose a stochastic magnetic field model, based on the dipole model, for the application of mapping a sensor network attached to an object with unknown position and shape. We validate the robustness of the model by testing it with different sensor network mapping configurations.

Acupuncture is a useful irritation therapy clinically. Acupuncture at acupoints is proved to have specific function on human body. Magnetic stimulation is a new kind of stimulating technique of non-invasive, painless and effective. The effect of magnetic stimulation on acupoint is a new subject in recent years. In this paper, the electroencephalogram (EEG) evoked potentials (EPs) of magnetic stimulation by stimulating the acupoint of Shenmen(HT7) are studied. The experiments are divided into four groups: quiet, acupoint stimulation, mock stimulation and mock point stimulation. The EEG EPs are collected and an obvious P150 component is obtained. The amplitudes of P150s are analyzed and compared. The P150s are localized in brain by dipole model and the coronal, sagittal and axial plans are painted and observed. The results show that acupoint stimulation on acupoint of Shenmen(HT7) can evoke stronger nerve activity of somatosensory than stimulation on common surface. The dipole source of acupoint stimulation and common surface stimulation are both focused on the cingulated gyrus which related to somatosensory.

An equivalent dipole model is proposed in this paper to represent the source of radiated electromagnetic emissions from an integrated circuit (IC). The height of an IC is usually much smaller than its length and width, so only three dipole moments are sufficient to characterize an IC in terms of its electromagnetic emissions. The dipole moments can be extracted from three TEM cell measurements. The radiated fields from the IC can then be calculated based on the extracted dipole sources. This IC emission model with three dipole moments is validated using the far-field measurements in a semi anechoic chamber for a test IC. For complex structures, it is desirable that the extracted dipole moments can be incorporated into a commercial full-wave tool as equivalent sources to simulate the radiations from an IC. This is demonstrated using an approach developed in this paper.

Low-level helicopter magnetometer data were collected over a site in Northern California that was contaminated with unexploded ordnance (UXO). Density estimates computed by selecting potential metallic anomalies from a derived total-gradient image identified a suspected bombing target but were distorted by large numbers of picks caused by geology. A dipole model was fit to each anomaly and used to estimate the apparent magnetic remanence. Restricting attention to items with low apparent remanence more clearly delineated the bombing target region and effectively eliminated the distortion of the density estimates caused by geology.

The standing-wave dipole and the traveling-wave monopole in time domain are proposed to model information technology equipment. The standing-wave dipole model can be easily got from some other references and the traveling-wave monopole model is built based on Rothwell's work with some revision made. The condition, on which selection can be made, is included. Features of the transient near zone and far zone fields are discussed of both models through examples. Good agreement is got between analysis and computed results plotted in the paper. Index Terms-standing-wave dipole, traveling-wave monopole, current pulse, transient fields.

An algorithm has been developed for detection of epileptiform activity in the EEG. The EEG is divided into overlapping epochs, which undergo two steps. The first is singular value decomposition (SVD) which identifies the number of uncorrelated active sources in an epoch. In the second step, EEG dipole source analysis, using a single dipole model, is applied to the EEG. This yields dipole parameters and a relative residual energy (RRE). The detection algorithm triggers an EEG epoch when SVD indicates a dominant source and the RRE is low. The algorithm is applied to simulated EEG generated by two sources which are synchronously and asynchronously active. For the synchronous case the critical measure is the RRE whereas for the asynchronous case both the SVD and RRE are critical. The algorithm has also been applied to real EEG containing two spikes and an eye-blink artifact. The SVD indicated a dominant active source and the RRE was low for all three events. These preliminary results demonstrate the potential of the method for detection of spikes and seizures with a focal origin.

We tested the validity of EEG and MEG source characterization of interictal spikes in epilepsy patients for which subdural grid registrations of the ECoG and accurate geometrical information from MRI and CT were available. A boundary element volume conduction model was used while for the inverse problem dipolar and distributed source models and epicortical potentials were tested. Results show that for a good qualitative correspondence between sources computed from EEG and ECoG signals distributed source models are to be preferred. For combined EEG-MEG the dipole model performs slightly better. For a good quantitative correspondence, proper modeling of the conductivity values and geometry is essential.

The complex fit normalized site attenuation (CFNSA) method was introduced in 2000 as an enhancement to the normalized site attenuation (NSA) model used in ANSI C63.4 and C63.5. The simple dipole NSA model is insufficient to predict the behavior of complex antennas like log periodic dipole arrays (LPDAs) and horns. Thus, NSA measurements made with these antennas using free-space antenna factors can have significant deviations from that predicted by the model. The CFNSA model is a modification to the simple dipole NSA model to account for the variations in antenna pattern and phase center that are possible in complex antennas. This paper evaluates the effectiveness of the phase center/pattern matching (PCPM) method previously proposed, as well as the use of directly measured pattern and phase center information, for a variety of antenna types.

A short dipole model with the 10-11 T nominal field based on the Nb/sub 3/Sn superconducting strand is being developed at Fermilab in collaboration with LBNL and KEK as part of the R&D effort for VLHC. This paper describes the magnet conceptual design and parameters as well as the results of magnetic field, mechanical and quench protection calculations. Parameters of the superconducting strand and cable are also reported.

From the single dipole model of the heart, there is a theoretical linear transformation that exists between the 12 lead and Frank lead ECGs. Using the CSE multilead database, the matrices to transform the 12 lead to the Frank lead ECGs were found for 125 recordings. An analysis of the matrices shows there is the wide variation of the individual matrix coefficients suggesting that the use of a universal matrix is inappropriate. >

Describes a method to find an appropriate neural network size for obtaining the inverse dipole solution for electrocardiography. A network size reduction algorithm has been proposed. Computer simulation under the single dipole model revealed that the algorithm can greatly reduce the number of hidden layer units while maintaining performance.

The design of a 700 MeV superconducting compact electron storage ring for applied X-ray lithography is in its final stage. This succeeds a 200 MeV warm dipole model constructed and now in operation at Brookhaven National Laboratory (BNL). RF cavities and systems in both machines are discussed. The authors present cavity design parameters, construction, and the kind of mode suppression as well as the type of tuner and input window to provide 300 kV of accelerating voltage at 211.54 MHz. A 65 kW, RF power source is described. >

Using magnetoencephalogram (MEG) and electroencephalogram (EEG) the source estimation is performed in recent research. We simulated the MEG source estimation (inverse problem) for the purpose of finding the spread and the amplitude of neural activities. We proposed the hexagonal spreading dipole (HSD) model to briefly describe the source's spread. Inverse simulation indicates that the source localization using the HSD model can be as accurate as the localization with a single dipole model. As the spread and the amplitude are associated with each other, it is effective to combine their information. However, it is significantly difficult to find the orientation of the HSD model, because the radial component of the neural source has few magnetic fields. The information of a cerebral cortex shape or EEG signal with a radial component should be applied to the source estimation algorithm.