Zobrazeno 1 - 10
of 39
pro vyhledávání: '"M D, Harpen"'
Publikováno v:
AJR. American journal of roentgenology. 173(5)
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cb7a1de6a5dd0e753a543c818d8be1e8
https://pubmed.ncbi.nlm.nih.gov/10541132
https://pubmed.ncbi.nlm.nih.gov/10541132
Autor:
M D, Harpen
Publikováno v:
Medical physics. 20(1)
The theory and operation of a resonator which produces a uniform oscillating magnetic field gradient is described. When the resonator is operated at audio frequency, it will produce the oscillating magnetic field gradient required for use in spatial
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=pmid________::5208fb9e790b05ca410f43ad17a819a8
https://pubmed.ncbi.nlm.nih.gov/8455488
https://pubmed.ncbi.nlm.nih.gov/8455488
Autor:
M D, Harpen
Publikováno v:
Medical physics. 19(3)
Presented is a theoretical description of the self-capacitance of a low-pass birdcage coil. The problem considered is that the modification of the distributed self-capacitance produced by the electric interaction between the coil and a cylindrical Fa
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=pmid________::21451e6b10c57fd36f4427769e65430e
https://pubmed.ncbi.nlm.nih.gov/1508099
https://pubmed.ncbi.nlm.nih.gov/1508099
Autor:
M D, Harpen
Publikováno v:
Magnetic resonance in medicine. 24(2)
Using a novel application of the method of images we show how a plane array of resonant elements can be substituted for the conducting plane in a semicylindrical or split resonator. In an experimental low-pass split resonator-plane array system used
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=pmid________::8edb9359f5ee8d4c16665fbc344563c3
https://pubmed.ncbi.nlm.nih.gov/1569874
https://pubmed.ncbi.nlm.nih.gov/1569874
Autor:
M D, Harpen
Publikováno v:
Medical physics. 18(5)
An analysis is presented of the interaction between a long cylindrical imaging coil, commonly called a low-pass birdcage coil, and a cylindrical sample. Predicted and measured values of coil Q are shown to compare well throughout the resonance spectr
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=pmid________::f60e494be830ff15a58ce07a35da7269
https://pubmed.ncbi.nlm.nih.gov/1961146
https://pubmed.ncbi.nlm.nih.gov/1961146
Autor:
M D, Harpen
Publikováno v:
Medical physics. 18(2)
A derivation of the power dissipation in a conducting spherical sample in a time-dependent gradient magnetic field is presented and the predicted values are compared with those observed in an experimental apparatus consisting of a four-element saddle
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=pmid________::1a4c124a1c64a9c22337a5f75f068b87
https://pubmed.ncbi.nlm.nih.gov/2046621
https://pubmed.ncbi.nlm.nih.gov/2046621
Autor:
M D, Harpen
Publikováno v:
Medical physics. 17(4)
Presented is a derivation of an exact closed-form expression for the spectra of resonant frequencies for magnetic resonance imaging birdcage coils in the limit of long coils with many elements. Results of the analysis are compared with observation in
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=pmid________::b19a781fe51a0e8683ecc7b8ebacc06d
https://pubmed.ncbi.nlm.nih.gov/2215415
https://pubmed.ncbi.nlm.nih.gov/2215415
Autor:
M D, Harpen
Publikováno v:
Medical physics. 17(3)
We present a solution to Maxwell's equations which describe the inductive interaction between an irregularly shaped sample in a magnetic resonance imaging rf coil. It is demonstrated that the inductive interaction between the coil and sample can indu
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=pmid________::0248e3db4865bc00482574fcf06f4f99
https://pubmed.ncbi.nlm.nih.gov/2385193
https://pubmed.ncbi.nlm.nih.gov/2385193
Autor:
V N, Mankad, J P, Williams, M D, Harpen, E, Manci, G, Longenecker, R B, Moore, A, Shah, Y M, Yang, B G, Brogdon
Publikováno v:
Blood. 75(1)
A longitudinal, prospective, controlled evaluation of magnetic resonance images (MRI) of long bones in sickle cell patients was undertaken simultaneously with assessment of clinical status and hematologic parameters, including dense erythrocytes. MRI
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=pmid________::0d6f2d47197b4305e7e8ab1b351f4ee3
https://pubmed.ncbi.nlm.nih.gov/2294992
https://pubmed.ncbi.nlm.nih.gov/2294992
Autor:
M D Harpen
Publikováno v:
Physics in Medicine and Biology. 34:1229-1238
Presents a general technique for the determination of eddy current distributions within an irregularly shaped conducting sample in the uniform field of an NMR RF coil. Also presented is a general expression for the sample-induced coil resistance. The
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::52ea337ab731cb1fb1acc3685962b11b
https://doi.org/10.1088/0031-9155/34/9/008
https://doi.org/10.1088/0031-9155/34/9/008