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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ejor.2005.06.038 Byline: Mozart B.C. Menezes (a), Seokjin Kim (b), Rongbing Huang (c) Keywords: Retailing; Queueing; Workforce; Service Management Abstract: An area supervisor managing an area chain of local urban retail stores faces the problem of determining the number of employees and allocating them to retail stores (workforce size and its allocation). We propose a model to maximize the overall expected profit rate of a coordinated area chain where employee absenteeism is uncertain. Retail stores operate as a Markovian loss queueing system. An efficient algorithm is proposed to optimize both workforce size and its allocation. We also provide insights for retail chain managers by comparing the optimal overall expected profit rates and the optimal workforce sizes of a coordinated area chain with those of its uncoordinated counterpart. Author Affiliation: (a) Department of Logistics and Operations Management, HEC School of Management - Paris, 1 Rue de la Liberation, F-78351 Jouy en Josas Cedex, France (b) Department of Business Administration, Millersville University, P.O. Box 1002, Millersville, PA 17551-0302, USA (c) School of Administrative Studies, Atkinson Faculty of Liberal & Professional Studies, York University, 4700 Keele Street, Toronto, Ont., Canada M3J 1P3 Article History: Received 5 August 2003; Accepted 28 June 2005

Graphical abstract Highlights • We isolated and characterized two EPS-producing bacterial strains from kimchi. • Both EPS were composed of glucose, fucose, mannose, galactose, and arabinose. • EPS yield was highest at an initial medium pH of 7.0. • Both EPS exhibited anti-inflammatory effects in LPS-stimulated RAW264.7 cells. Abstract The immunomodulatory properties of exopolysaccharides (EPS), major components of bacterial biofilm, are not fully understood. Here, we examined the immunomodulatory potential of EPS derived from Bacillus licheniformis BioE-BL11 and Leuconostoc mesenteroides BioE-LMD18, isolated from Korean fermented kimchi. EPS from BioE-BL11 was composed of mannose (12.4%), galactose (1.82%), glucose (48.5%), fucose (37.1%), and arabinose (0.17%), and that from BioE-LMD18 was composed of mannose (8.71%), arabinose (0.07%), galactose (1.22%), glucose (79.8%), and fucose (10.21%). The highest EPS yield were obtained by incubation at 37 °C for 3 days with an initial pH of 7.0, without optimizing other conditions. The EPS from BioE-BL11 and BioE-LMD18 significantly inhibited secretion of the pro-inflammatory cytokine IL-6 in lipopolysaccharide-stimulated RAW264.7 mouse macrophage by 40.7% and 32.1%, respectively, enhanced secretion of the anti-inflammatory cytokine IL-10 in a dose-dependent manner, suggesting that EPS produced by these strains may be useful functional ingredients for the cosmetics, food, and pharmaceuticals industries. [ABSTRACT FROM AUTHOR]

We demonstrated an all-fiber phase noise measurement technique to detect transient phase variation of polarization maintaining Yb-doped fiber amplifier based on active phase locking of an optical heterodyne detection system. The root mean square, power spectral density, and drift velocity in the phase noise were analyzed for both core-pumped single clad fiber amplifier and clad-pumped double-clad fiber amplifier. The phase noise was further analyzed in terms of the seed laser power, amplifier output power, and fiber optic component configurations. The phase drift velocity measurements at various amplifier output powers indicated the optical phase were closely related to the temperature variations. [ABSTRACT FROM AUTHOR]

Developing lithium-ion batteries with high power and fast charging features has been highlighted as an essential research area to address growing energy demands for portable electronics and long-range electric vehicles. The commercial graphite anode has been recognized as a competent material owing to its benefits, including a long cycle life, high columbic efficiency, and low volume expansion. However, the intrinsic features of their intercalation kinetics render them highly susceptible to lithium deposition, resulting in poor cycle stability at fast charging conditions. In this study, we propose a simple thermal fluorine treatment of flake-type graphite to produce fluorine-doped-flake graphite. We observed the fluorine treatment improves the Li+ ion intercalation kinetics and reduces the lithium deposition and dendrite growth upon fast charging conditions. As a result, enhanced lithiation behavior was observed, with a high specific capacity of 348.3 mAh g−1 and a good rate capability of 66 % at 2C-rate in half-cell conditions. Furthermore, a full cell demonstrated outstanding cycle stability with 83.5 % capacity retention at 2C even after 950 cycles. Our findings emphasize that fluorine doping in graphite could be a straightforward and practical approach to mitigate Li deposition issues and enhance the fast charge kinetics of graphite-based commercial Li-ion batteries. [Display omitted] [ABSTRACT FROM AUTHOR]

We experimentally demonstrated a tunable microsecond passively Q-switched fiber laser using deionized water (DIW) as a saturable absorber (SA). The DIW-SA was integrated into an all-fiber device by filling the gap between two cleaved fiber facets with DIW, which were enclosed in a glass ferrule. We observed a high nonlinear transmission through DIW-SA and implemented it in an erbium-doped fiber ring laser cavity. Microsecond Q-switched pulse trains were produced tunable from 1564.3 to 1603.4 nm using a fiber-optic Fabry-Perot interference filter within the cavity, avoiding peak water absorption while maintaining stable operation. Tunable and robust Q-switching of a fiber laser using water would open a new avenue of nonlinear aqua-photonics. • The proposed deionized water (DIW) saturable absorber (SA) contains DIW between SMFs to significantly relieve absorption to mitigate the overall cavity loss. In contrast to prior methods, the gap distance between SMFs was reduced by more than 1000 times to obtain a very low insertion loss, enabling wide spectral tunability of a filter. • An all-fiber Fabry-Perot interferometer (FPI) tunable filter was formed by using two cleaved single-mode fibers with a variable air gap. The FPI filter made the Q-switched laser's center wavelength tunable from 1564.3 to 1603.4 nm, covering both C-and L-bands • By integrating the proposed DIW-SA and FPI filter in an Er-doped fiber ring laser cavity, tunable microsecond Q-switched laser pulse trains were successfully generatedachieving the longest lasing wavelength at λ = 1603.4 nm. [ABSTRACT FROM AUTHOR]

Abstract: A microelectromechanical shock sensor, which uses a latching mechanism to record a shock event above a specified threshold level, is discussed in this article. The fabrication process for the shock sensor, which includes wafer-level vacuum packaging, is detailed along with the design features. These features include a reset actuator for reuse of the sensor, a no-power operation scheme when the reset actuator is not activated, and a control circuit to minimize power used to unlatch the sensor. In order to describe the shock-sensor dynamics and interaction with the latch mechanism, a preliminary non-linear model has been developed. Experimental results are presented and compared with model predictions. [Copyright &y& Elsevier]