10,652 research outputs found
On the Determinations of Class-Based Storage Assignments in AS/RS having two I/O Locations
This paper presents the use and extension of a geometrical-based algorithmic approach for determining the expected S/R machine cycle times, and therefore warehouse throughput, for class-based storage assignment layouts in an AS/RS.The approach was designed for the purpose of solving a practical storage assignment design problem for a major European manufacturer.The algorithm may be used to layout racks that are either "square-in-time (SIT)" or "non-square in time (NSIT)" with single or multiple I/O points.It is believed that use of this approach can result in the expedient evaluation of warehouse throughput resulting from new layouts, or re-layouts, of AS/R system racks, thus making these systems more appealing for use in integrated supply chain systems in general.production management;manufacturing;supply chain mangement;warehousing;storage
From spin-Peierls to superconductivity: (TMTTF)_2PF_6 under high pressure
The nature of the attractive electron-electron interaction, leading to the
formation of Cooper-pairs in unconventional superconductors has still to be
fully understood and is subject to intensive research. Here we show that the
sequence spin-Peierls, antiferromagnetism, superconductivity observed in
(TMTTF)_2PF_6 under pressure makes the (TM)_2X phase diagram universal. We
argue that the suppression of the spin-Peierls transition under pressure, the
close vicinity of antiferromagnetic and superconducting phases at high pressure
as well as the existence of critical antiferromagnetic fluctuations above T_c
strongly support the intriguing possibility that the interchain exchange of
antiferromagnetic fluctuations provides the pairing mechanism required for
bound charge carriers.Comment: 4 pages, revtex, 4 figures (jpeg,eps,png
Computer-assisted ex vivo, normothermic small bowel perfusion
Background: In the present study, a technique for computer-assisted, normothermic, oxygenated, ex vivo, recirculating small bowel perfusion was established as a tool to investigate organ pretreatment protocols and ischemia/reperfusion phenomena. A prerequisite for the desired setup was an organ chamber for ex vivo perfusion and the use of syngeneic whole blood as perfusate. Methods: The entire small bowel was harvested from Lewis rats and perfused in an organ chamber ex vivo for at least 2 h. The temperature was kept at 37 degrees C in a water bath. Three experimental groups were explored, characterized by different perfusion solutions. The basic perfusate consisted of syngeneic whole blood diluted with either NaCl, Krebs' solution or Krebs' solution and norepinephrine to a hematocrit of 30%. In addition, in each group l-glutamine was administered intraluminally. The desired perfusion pressure was 100 mm Hg which was kept constant with a computer-assisted data acquisition software, which measured an-line pressure, oxygenation, flow, temperature and pH and adjusted the pressure by changing the flow via a peristaltic pump. The viability of the preparation was tested by measuring oxygen consumption and maltose absorption, which requires intact enzymes of the mucosal brush border to break down maltose into glucose. Results: Organ perfusion in group 1 (dilution with NaCl) revealed problems such as hypersecretion into the bowel lumen, low vascular resistance and no maltose uptake. In contrast a viable organ could be demonstrated using Krebs' solution as dilution solution. The addition of norepinephrine led to an improved perfusion over the entire perfusion period. Maltose absorption was comparable to tests conducted with native small bower. Oxygen consumption was stable during the 2-hour perfusion period. Conclusions: The ex vivo perfusion system established enables small bowel perfusion for at least 2 h. The viability of the graft could be demonstrated. The perfusion time achieved is sufficient to study leukocyte/lymphocyte interaction with the endothelium of the graft vessels. In addition, a viable small bowel, after 2 h of ex vivo perfusion, facilitates testing of pretreatment protocols for the reduction of the immunogenicity of small bowel allografts. Copyright (C) 2000 S. Karger AG, Basel
Space station integrated wall design and penetration damage control. Task 3: Theoretical analysis of penetration mechanics
The efforts to provide a penetration code called PEN4 version 10 is documented for calculation of projectile and target states for the impact of 2024-T3 aluminum, R sub B 90 1018 steel projectiles and icy meteoroids onto 2024-T3 aluminum plates at impact velocities from 0 to 16 km/s. PEN4 determines whether a plate is perforated by calculating the state of fragmentation of projectile and first plate. Depth of penetration into the second to n sup th plate by fragments resulting from first plate perforation is determined by multiple cratering. The results from applications are given
European surveillance of infections in cancer patients - ESIC
Major advances in cancer therapy result from development of multidrug chemotherapy regimens. Besides death from tumor progression, infections are currently one of the major causes of mortality and morbidity. Because of the risk of complications and mortality, the treatment for febrile neutropenia is admission to hospital and administration of broad-spectrum antibiotics. Response rates of initial antimicrobial treatment vary considerably (40-92%). Due to the heterogeneity of populations in randomized studies, comparison of efficacy and identification of risk factors is limited. This is the main reason why the European Society of Biomodulation and Chemotherapy (ESBiC) is conducting a surveillance study that concentrates more on the evaluation of risk factors than on the therapeutic outcome of prospective randomized antimicrobial regimens: European Surveillance of Infections in Cancer Patients (ESIC). The present contribution is to determine which cancer patients are at low risk for fever, and can benefit from first-line treatment with treatment options such as monotherapy as well as on an outpatient basis
Decoherence of Flux Qubits Coupled to Electronic Circuits
On the way to solid-state quantum computing, overcoming decoherence is the
central issue. In this contribution, we discuss the modeling of decoherence of
a superonducting flux qubit coupled to dissipative electronic circuitry. We
discuss its impact on single qubit decoherence rates and on the performance of
two-qubit gates. These results can be used for designing decoherence-optimal
setups.Comment: 16 pages, 5 figures, to appear in Advances in Solid State Physics,
Vol. 43 (2003
Assessment of the U and Co magnetic moments in UCoGe by X-ray magnetic circular dichroism
The ferromagnetic superconductor UCoGe has been investigated by high field
X-ray magnetic circular dichroism (XMCD) at the U-M and Co/Ge-K edges.
The analysis of the branching ratio and XMCD at the U-M edges reveals
that the U-5 electrons count is close to 3. The orbital ()
and spin () moments of U at 2.1K and 17T (H//c) have been
determined. Their ratio () suggests a significant delocalization of
the 5 electron states. The similar field dependences of the local U/Co and
the macroscopic magnetization indicate that the Co moment is induced by the U
moment. The XMCD at the Co/Ge-K edges reveal the presence of small Co-4 and
Ge-4 orbital moments parallel to the macroscopic magnetization. In addition,
the Co-3 moment is estimated to be at most of the order of 0.1 at
17T. Our results rule out the possibility of an unusual polarisability of the U
and Co moments as well as their antiparallel coupling. We conclude that the
magnetism which mediates the superconductivity in UCoGe is driven by U.Comment: 4 figures + supplementary materia
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