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61.
C. A. Isler G. M. Righetto R. Morabito 《The International Journal of Advanced Manufacturing Technology》2016,87(5-8):2327-2336
The warehouse operation planning in the scholar and office supplies industry encompasses the activities of receiving, storing, order picking, and shipping products. The order picking operation is a laborious and capital intensive procedure. Despite the extensive literature to solve practical problems of warehouse routing as a step of the order picking process, the application of general approaches to deal with the routing of the warehouse pickers is not straightforward given the specific conditions and configurations and the singular design and operational policies commonly found in practice. In this paper, we present an optimization approach to the stacker routing problem found in the order picking of a Brazilian scholar and office supplies company. The approach is based on a routing algorithm that solves different integer linear problems to define the optimal routes of the stacker inside the facility. The solutions of several numerical experiments show the potential and effectiveness of the approach, for instance, that only one fifth of the routes actually performed by the company are optimal and that the algorithm application to a real set of batches reduced by more than one fourth the total distance monthly traveled by the stacker. 相似文献
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Daytime sleep tendency was assessed in 10 drug-free patients with narcolepsy-cataplexy and 10 normals matched for age and gender. Following nocturnal polysomnography, the alpha attenuation test (AAT) and the multiple sleep latency test (MSLT) were administered during five sessions occurring at 2-hour intervals beginning at 0900 and 1000 hours, respectively. For the AAT, participants were polysomnographically recorded for 8 minutes while seated in an illuminated room with their eyes alternately opened and closed. Power spectral analyses of electroencephalograph (EEG) activity at 02-A1 (10 second epochs) were calculated using fast Fourier transformations (FFT) within the alpha frequency range (8-12 Hz) to obtain ratios of mean eyes-closed to mean eyes-open alpha power (i.e. the alpha attenuation coefficient, AAC). The narcoleptics were sleepier than the normals as indicated by a significantly smaller mean AAC and a significantly shorter mean latency to stage 1 on the MSLT. These findings suggest that the AAT may provide a quick and practical objective assessment of the excessive daytime sleepiness (EDS) associated with narcolepsy. 相似文献
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RD Barr T Simpson CE Webber GJ Gill J Hay M Eves AC Whitton 《Canadian Metallurgical Quarterly》1998,34(6):873-877
Mature and post-translational precursor gastrin forms are growth factors for colorectal tumours. The immunogen Gastrimmune is composed of the amino terminus of gastrin-17 linked to diphtheria toxoid and raises antibodies in situ which neutralise amidated and glycine-extended gastrin-17. The aim of the study was to determine the effect of treatment with 5-fluorouracil(5-FU)/leucovorin on the antibody titres induced by Gastrimmune and the effect of combination therapy on the growth of the rat colon tumour DHDK12. Gastrimmune was administered to rats s.c. at 3 weekly intervals. The rat colon tumour line DHDK12 was injected into the abdominal wall of BDIX rats. Combinations of 5-FU/leucovorin were injected i.v. on days 1, 3 and 5, with the cycle repeated every 4 weeks. Antibody titres were measured by an ELISA technique. Antibody titres were followed for 40 weeks after Gastrimmune (500 microg.ml(-1)) immunization, with titres peaking between 10 and 20 weeks after a single immunisation and falling by week 30. At termination, no effect was observed on either the histological appearance of the gastro-intestinal tract or the proliferation of the colonic mucosa. Pre- and post-treatment with 5-FU/leucovorin (30 mg.kg(-1)) had no effect on the kinetics and level of antibody response to Gastrimmune. Gastrimmune (200 microg.ml(-1)) and 5-FU/leucovorin combinations (12.5 and 20 mg.kg(-1)) increased the therapeutic effects on the in vivo growth of DHDK12 tumors when compared to the agents given singly. Gastrimmune immunisation may be a therapeutic option for the treatment of colorectal cancer in combination with 5-FU/leucovorin. 相似文献
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