334 research outputs found
Symmetry consideration and eg bands in NdNiO3 and YNiO3
Group theoretical analyses are applied to the magnetic and electronic
structures of NdNiO3 and YNiO3, whose electronic structures have been studied
very recently by the LSDA+U method. The Jahn-Teller distortion cannot satisfy
the experimentally observed magnetic diffraction. The resultant ground state
magnetic stuructures are monoclinic P_ba in NdNiO3 case and P_b2_1/a in YNiO3
case, respectively.Comment: 6 pages, 3 figures, Proc. Int. Symp. ISSP-Kashiwa 200
Charge and spin stripe in LaSrNiO (x=1/3,1/2)
Electronic structure of stripe ordered LaSrNiO is
investigated. The system with x=1/3 is insulator, in LSDA+U calculations, and
shows charge and spin stripe, consistent with the experimental results. Highly
correlated system of x=1/2 is studied by using exact diagonalization of
multi-orbital many body Hamiltonian derived from LDA calculations and including
on-site and inter-site Coulomb interactions. The fluctuation of the residual
spin on Ni (hole) site couples with the charge fluctuation between
Ni and Ni states and this correlation lowers the total energy.
The resultant ground state is insulator with charge and spin stripe of the
energy gap 0.9eV, consistent with observed one. The on-site Coulomb interaction
stabilizes integral valency of each Ni ion (Ni and Ni), but does
not induce the charge order. Two quantities, inter-site Coulomb interaction and
anisotropy of hopping integrals, play an important role to form the charge and
spin stripe order in a system of x=1/2.Comment: 12 pages, 10 figures, fully revise
The Computer Programs of Layout Methods Based on Decision Making Theory
We tried to look at the allocation techniques in plant layout from the point of view of decision making theory. And it was made clear that Laplace, Minimax and Hurwicz princilpe can be applied to the allocation techniques. The techniques based on these principles were called Laplace method, Minimax method and Hurwicz method. In this paper algorithms and computer programs of these methods were described in order to solve the layout problems effectively
Allocation Technique Using Relative Distance and Relative Volume Estimated by Statistical Procedure
This paper deals with the allocation technique of the layout whose solution it takes as a little computation time as possible to obtain and which becomes as near to the optimal method as possible. In this method, the relative transport distance of each location and the relative transport volume of each department are calculated from the distance matrix and the volume matriX by the statistical procedures. And allocating departments to locations is determined by one to one correspondence between the arranged relative transport distances and the arranged relative transport volumes. This method was called the allocation technique by the statistical procedure ( ATSP in short ).
This method doesn't use the heuristic algorithm.
Therefore the calculation time can be reduced much in
comparison with any other methods. As the algorithm
of ATSP method is very simple, the sub-optimal layout
can be determined easily by using the desk-calculator
in cases of any layout problems
Symmetry-adapted HAM/3 method and its application to some symmetric molecules
The semiempirical HAM/3 method developed by Lindholm and coworkers about two decades ago has been known to have a deficiency that splits energies for the degenerate energy states. We have recently proposed a group-theoretical approach to remedy the internally broken symmetry of the HAM/3 Hamiltonians. In this paper, we present some results of its application to various small molecules with symmetry Td, C3v, and D3h. The proposed scheme gives correct degeneracy for these molecules.O método semi-empírico HAM/3, desenvolvido por Lindholm e colaboradores há mais de duas décadas, tem uma deficiência. As energias de excitação calculadas por HAM/3 para estados degenerados são desdobradas. Recentemente foi proposto um método para corrigir esta deficiência. Apresentamos aqui resultados de aplicações deste novo método para algumas moléculas com simetria Td, C3v e D3h. O esquema proposto apresenta a degenerescência correta para as moléculas estudadas.445449Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Hepatic infarction following abdominal interventional procedures.
To clarify the incidence, background, and progress of hepatic infarction following interventional procedures, cases of hepatic infarction following interventional procedures at our department during the last decade were identified by reviewing the clinical records of 1982 abdominal angiography and interventional procedures and records of abdominal CT. Nine episodes (0.5%) in 8 patients were identified as hepatic infarction following an interventional procedure. Five episodes were preceded by embolization of the hepatic or celiac artery at emergency angiography for postoperative bleeding with hemorrhagic shock. Three episodes followed the elected interventional procedure for hepatocellular carcinoma, and the remaining episode occurred after 12 months of chemoinfusion through an indwelling catheter in the hepatic artery and portal vein. Hepatic arterial occlusion in all episodes and portal venous flow abnormality in 5 episodes were observed on angiography. Four patients whose liver function was initially impaired died of hepatic infarction, although the extent of the disease on CT did not appear to be related to the mortality. Multiple risk factors, including arterial insufficiency, were observed in each patient. The incidence of hepatic infarction following interventional procedures in this series was low but sometimes fatal, and occurred most frequently in emergency embolization in hemorrhagic shock.</p
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