566 research outputs found
Lie algebra cohomology and group structure of gauge theories
We explicitly construct the adjoint operator of coboundary operator and
obtain the Hodge decomposition theorem and the Poincar\'e duality for the Lie
algebra cohomology of the infinite-dimensional gauge transformation group. We
show that the adjoint of the coboundary operator can be identified with the
BRST adjoint generator for the Lie algebra cohomology induced by
BRST generator . We also point out an interesting duality relation -
Poincar\'e duality - with respect to gauge anomalies and Wess-Zumino-Witten
topological terms. We consider the consistent embedding of the BRST adjoint
generator into the relativistic phase space and identify the
noncovariant symmetry recently discovered in QED with the BRST adjoint N\"other
charge .Comment: 24 pages, RevTex, Revised version submitted to J. Math. Phy
Strategies For Manufacturing Servitization Of Korean SMEs: By Using Data Envelopment Analysis
This study examines the efficiency of Korean manufacturing SMEs through data envelopment analysis. We divide business processes into support activities (e.g., business management and product planning) and primary activities (e.g., production and sales and after-sales services) to measure the efficiency of each process by product module. Moreover, we verify the effect of manufacturing servitization by comparing between the efficiency of servitized and non-servitized firms. The result shows that support activities are generally more efficient than primary activities and that standardized mass production with option (module 2) and totally customized production (module 4) is more efficient than either standardized mass production without option (module 1) or customized assembly after standardized production (module 3). The results suggest that, as SMEs are small, they have an advantage in support activities but also lack production and sales channel infrastructure. Moreover, modules 2 and 4 are relatively efficient because they can increase their product values via product differentiation. In addition, servitized firms are more efficient than non-servitized firms in almost every process and module, implying that servitization in manufacturing is an effective way to improve product value. Finally, module 1 and the production process are relatively inefficient, while servitized firms have higher efficiency scores than do non servitized firms. Likewise, module 3 and sales and after-sales services are relatively inefficient, while servitized firms have higher efficiency scores than do non servitized firms. There results imply that servitization can be used by Korean manufacturing SMEs to develop efficiently and effectively
Analysis of Initial Baseline Clinical Parameters and Treatment Strategy Associated with Medication Failure in the Treatment of Benign Prostatic Hyperplasia in Korea
Purpose To analyze the baseline clinical factors and medication treatment strategy used in cases with medication treatment failure of benign prostatic hyperplasia (BPH). Methods From January 2006 to December 2009, 677 BPH patients with at least 3 months of treatment with medication were enrolled. We analyzed clinical factors by medication failure (n=161) versus maintenance (n=516), by prostate size (less than 30 g, n=231; 30 to 50 g, n=244; greater than 50 g, n=202), and by prostate-specific antigen (PSA) levels (less than 1.4 ng/mL, n=324; more than 1.4 ng/mL, n=353). Results Age, combination medication rate, PSA, and prostate volume were statistically different between the medication treatment failure and maintenance groups. By prostate size, the PSA and medication failure rates were relatively higher and the medication period was shorter in patients with a prostate size of more than 30 g. The combination medication rate was higher in patients with a prostate size of more than 50 g. The medication failure rate and prostate volume were higher in patients with a PSA level of more than 1.4 ng/mL. However, the combination treatment rate was not significantly different in patients with a PSA level lower than 1.4 ng/mL. Suggestive cutoffs for combination medication are a prostate volume of 34 g and PSA level of 1.9 ng/mL. Conclusions The clinical factors associated with medication failure were age, treatment type, and prostate volume. Combination therapy should be considered more in Korea in patients with a PSA level higher than 1.4 ng/mL and a prostate volume of between 30 and 50 g to prevent medication failure
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