An application of the target field method to the design of shielded biplanar gradient coils for magnetic resonance imaging electromagnets is presented. Some specific cases are studied, and optimized geometries are proposed for the axial and transverse gradient coils that eliminate the third- and minimize the fifth-order terms in the magnetic field expansion.

it was important to study the shielded effectiveness to reduce the electromagnetic interference and to protect electronic components. in this paper, the boundary element equation of linear segment was derived from the two-dimension boundary integral equation and linear interpolating function, and the formulas of potential and electric field intensity were also given. To demonstrate the accuracy...

BACKGROUND Interstitial rotating shield brachytherapy (I-RSBT) is a recently developed method for treatment of prostate cancer. In the present study TG-43 dosimetric parameters of a 153Gd source were obtained for use in I-RSBT. MATERIALS AND METHODS A 153Gd source located inside a needle including a Pt shield and an aluminum window was simulated using MCNPX Monte Carlo code. Dosimetric parame...

By introducing extra shields on Shpilrain and Ushakov’s Ko-Lee-like protocol based on the decomposition problem of group elements we propose two new key exchange schemes and then a number of public key cryptographic protocols. We show that these protocols are free of known attacks. Particularly, if the entities taking part in our protocols create their private keys composed by the generators of...

Developing larvae of the Japanese newt, Cynops pyrrhogaster, were subjected for 5 days to a shielded environment in which the static magnetic field was about 10,000 times weaker (5 nT) than the geomagnetic norm, which ranges between 30 and 60 microT at the earth's surface. Larvae from non-cleavage to neurula stages were exposed under shielded or normal (control) conditions and then examined for...

This paper presents two methods for determining the complex antenna factor (CAF) of a shielded loop antenna for HF magnetic field measurements. A circuit model is introduced to apply the field-transferred 3-antenna method to double-loaded shielded loop antennas. In addition, a new 3-antenna method is proposed, where theoretical calculation and circuit measurement are combined. Experiments are m...

The health effects of radiation exposure from the atomic bomb fallout remain unclear. The objective of the present study is to elucidate the association between low-dose radiation exposure from the atomic bomb fallout and cancer mortality among Nagasaki atomic bomb survivors. Of 77 884 members in the Nagasaki University Atomic Bomb Survivors Cohort, 610 residents in the terrain-shielded area wi...

We examined the dose from mTc contained in syringes and shielded vials to assess in detail the dose burdens in a central pharmacy. Methods: Absorbed-dose rates at the end of the plunger of a shielded syringe, when mTc is contained either in the syringe or in a shielded vial from which the activity would be drawn, were measured with CaF2 dosimeters. The dose rates also were calculated with a Mon...