6,491 research outputs found
USp(2k) Matrix Model: Schwinger-Dyson Equations and Closed-Open String Interactions
We derive the Schwinger-Dyson/loop equations for the USp(2k) matrix model
which close among the closed and open Wilson loop variables. These loop
equations exhibit a complete set of the joining and splitting interactions
required for the nonorientable Type I superstrings. The open loops realize the
SO(2n_f) Chan-Paton factor and their linearized loop equations derive the mixed
Dirichlet/Neumann boundary conditions.Comment: 22 pages, 13 figure
USp(2k) Matrix Model
We review the construction and theoretical implications of the USp(2k) matrix
model in zero dimension introduced in ref. \cite{IT1,IT2}. It is argued that
the model provides a constructive approach to Type I superstrings and is at the
same time dynamical theory of spacetime points. Three subjects are discussed :
semiclassical pictures and series of degenerate perturbative vacua associated
with the worldvolume representation of the model, the formation of extended
(D-)objects from the fermionic integrations via the (non-)abelian Berry phase,
and the Schwinger-Dyson/loop equations which exhibit the joining-splitting
interactions required. Lectures presented at the 13th Nishinomiya-Yukawa
Memorial Symposium ``Dynamics of Fields and Strings'' (November 12-13,1998) and
at the YITP workshop (November 16-18, 1998).Comment: 32 pages, Latex with PTPTex.sty, 16 epsf figure
Determinant formula for the six-vertex model with reflecting end
Using the Quantum Inverse Scattering Method for the XXZ model with open
boundary conditions, we obtained the determinant formula for the six vertex
model with reflecting end.Comment: 10 page
Environmental change pattern in central Japan as revealed by LANDSAT data
The author has identified the following significant results. A patched cirrus reported by weather stations was hardly recognizable by the eye in LANDSAT MSS data of a three year time lapse. The cloud cover affected radiance values significantly in band 4, while its effect was minimal in bands 6 and 7 (near infrared spectra). The cross correlation coefficient analysis between the two images indicated that the highest value obtained in central Japan was 0.963 for the area where little change occurred in land use over the three period. An analysis of land use in Nagoya showed little change in the metropolitan area while a fairly large change occurred in the northern periphery of the city where large scale housing projects are located
String Field Theory from IIB Matrix Model
We derive Schwinger-Dyson equations for the Wilson loops of a type IIB matrix
model. Superstring coordinates are introduced through the construction of the
loop space. We show that the continuum limit of the loop equation reproduces
the light-cone superstring field theory of type IIB superstring in the large-N
limit. We find that the interacting string theory can be obtained in the double
scaling limit as it is expected.Comment: 21 pages, Latex, 1 figur
Combining Rasch and cluster analysis: a novel method for developing rheumatoid arthritis states for use in valuation studies
Purpose: Health states that describe an investigated condition are a crucial component of valuation studies. The health states need to be distinct, comprehensible, and data-driven. The objective of this study was to describe a novel application of Rasch and cluster analyses in the development of three rheumatoid arthritis health states.
Methods: The Stanford Health Assessment Questionnaire (HAQ) was subjected to Rasch analysis to select the items that best represent disability. K-means cluster analysis produced health states with the levels of the selected items. The pain and discomfort domain from the EuroQol-5D was incorporated at the final stage.
Results: The results demonstrate a methodology for reducing a dataset containing individual disease-specific scores to generate health states. The four selected HAQ items were bending down, climbing steps, lifting a cup to your mouth, and standing up from a chair.
Conclusions: Overall, the combined use of Rasch and cluster analysis has proved to be an effective technique for identifying the most important items and levels for the construction of health states
Combining Rasch and cluster analysis: a novel method for developing rheumatoid arthritis states for use in valuation studies
Purpose: Health states that describe an investigated condition are a crucial component of valuation studies. The health states need to be distinct, comprehensible, and data-driven. The objective of this study was to describe a novel application of Rasch and cluster analyses in the development of three rheumatoid arthritis health states. Methods: The Stanford Health Assessment Questionnaire (HAQ) was subjected to Rasch analysis to select the items that best represent disability. K-means cluster analysis produced health states with the levels of the selected items. The pain and discomfort domain from the EuroQol-5D was incorporated at the final stage. Results: The results demonstrate a methodology for reducing a dataset containing individual disease-specific scores to generate health states. The four selected HAQ items were bending down, climbing steps, lifting a cup to your mouth, and standing up from a chair. Conclusions: Overall, the combined use of Rasch and cluster analysis has proved to be an effective technique for identifying the most important items and levels for the construction of health states.health state; Rasch analysis; cluster analysis; quality of life; rheumatoid arthritis
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