2,032 research outputs found
An agent-based negotiation model to support partner selection in a virtual enterprise
Session - MP-Fd Supply Chain Management & Logistics 4: cie182hk-1Conference Theme: Soft Computing Techniques for Advanced Manufacturing and Service SystemsIn response to the global business competitive environment, it is common for several companies to participate in a virtual enterprise (VE) to cooperate and collaborate dynamically to complete a common business opportunity. This paper proposes an agent-based negotiation model to support the partner selection process in a VE. To begin with, the VE partner selection problem is abstracted as a buyer-seller relationship such that the VE initiator is the buyer and the VE partners are sellers or vice verse. In the multi-agent system (MAS) that supports the proposed negotiation model, autonomous agents are established to represent various parties and functions of the VE. For instance, a buyer agent represents the VE initiator and the potential partners are represented by seller agents. Thus, the VE partner evaluation and selection problem is the process of finding the partners that are able to provide the buyer with the right quality products and services at the right price and at the right time. Evaluation and selection of partners is a typical multiattribute decision making (MADM) problem involving various issues that can both be qualitative and quantitative.published_or_final_versionThe 40th International Conference on Computers & Industrial Engineering (CIE40), Awaji City, Japan, 25-28 July 2010. In Proceedings of the International Conference on Computers and Industrial Engineering, 2010, p. 1-
Elastic modulus of ASR-affected concrete: An evaluation using Artificial Neural Network
Copyright © 2019 Techno-Press, Ltd. Alkali-silica reaction (ASR) in concrete can induce degradation in its mechanical properties, leading to compromised serviceability and even loss in load capacity of concrete structures. Compared to other properties, ASR often affects the modulus of elasticity more significantly. Several empirical models have thus been established to estimate elastic modulus reduction based on the ASR expansion only for condition assessment and capacity evaluation of the distressed structures. However, it has been observed from experimental studies in the literature that for any given level of ASR expansion, there are significant variations on the measured modulus of elasticity. In fact, many other factors, such as cement content, reactive aggregate type, exposure condition, additional alkali and concrete strength, have been commonly known in contribution to changes of concrete elastic modulus due to ASR. In this study, an artificial intelligent model using artificial neural network (ANN) is proposed for the first time to provide an innovative approach for evaluation of the elastic modulus of ASR-affected concrete, which is able to take into account contribution of several influence factors. By intelligently fusing multiple information, the proposed ANN model can provide an accurate estimation of the modulus of elasticity, which shows a significant improvement from empirical based models used in current practice. The results also indicate that expansion due to ASR is not the only factor contributing to the stiffness change, and various factors have to be included during the evaluation
On the supranational spell of PISA in policy
BACKGROUND: PISA results appear to have a large impact upon government policy. The phenomenon is growing, with more countries taking part in PISA testing and politicians pointing to PISA results as reasons for their reforms.
PURPOSE: The aims of this research were to depict the policy reactions to PISA across a number of jurisdictions, to see whether they exhibited similar patterns and whether the same reforms were evident.
SOURCES OF EVIDENCE: We investigated policy and media reactions to the 2009 and 2012 PISA results in six cases: Canada, China (Shanghai), England, France, Norway and Switzerland. Cases were selected to contrast high-performing jurisdictions (Canada, China) with average performers (England, France, Norway and Switzerland). Countries that had already been well reported on in the literature were excluded (Finland, Germany).
DESIGN AND METHODS: Policy documents, media reports and academic articles in English, French, Mandarin and Norwegian relating to each of the cases were critically evaluated.
RESULTS: A policy reaction of ‘scandalisation’ was evident in four of the six cases; a technique used to motivate change. Five of the six cases showed ‘standards-based reforms’ and two had reforms in line with the ‘ideal-governance’ model. However, these are categorisations: the actual reforms had significant differences across countries. There are chronological problems with the notion that PISA results were causal with regard to policy in some instances. Countries with similar PISA results responded with different policies, reflecting their differing cultural and historical education system trajectories.
CONCLUSIONS: The connection between PISA results and policy is not always obvious. The supranational spell of PISA in policy is in the way that PISA results are used as a magic wand in political rhetoric, as though they conjure particular policy choices. This serves as a distraction from the ideological basis for reforms. The same PISA results could motivate a range of different policy solutions
Expression of GD2 and GD3 gangliosides in human embryonic neural stem cells
NSCs (neural stem cells) are undifferentiated neural cells endowed with a high potential for proliferation and a capacity for self-renewal with retention of multipotency to differentiate into neurons and glial cells. It has been recently reported that GD3, a b-series ganglioside, is a marker molecule for identifying and isolating mouse NSCs. However, the expression of gangliosides in human NSCs is largely unknown. In the present study, we analysed the expression of gangliosides, GD2 and GD3, in human NSCs that were isolated from human brains at gestational week 17 in the form of neurospheres, which are floating clonal aggregates formed by NSCs in vitro. Employing immunocytochemistry, we found that human NSCs were strongly reactive to anti-GD2 antibody and relatively weakly reactive to anti-GD3 antibody. Treatment of these cells with an organic solvent such as 100% methanol, which selectively removes glycolipids from plasma membrane, abolished the immunoreactivity with those antibodies, indicating that the reactivity was due to GD2 and GD3, but not to GD2-/GD3-like glycoproteins or proteoglycans. The immunoreactivity of human NSCs to antibody against SSEA-1 (stage-specific embryonic antigen-1), a well-known carbohydrate antigen of NSCs, was not decreased by the treatment with 100% methanol, indicating that SSEA-1 is mainly carried by glycoproteins and/or proteoglycans in human NSCs. Our study suggests that GD2 and GD3 can be marker gangliosides for identifying human NSCs
Ganglioside composition and histology of a spontaneous metastatic brain tumour in the VM mouse
Glycosphingolipid abnormalities have long been implicated in tumour malignancy and metastasis. Gangliosides are a family of sialic acid-containing glycosphingolipids that modulate cell–cell and cell–matrix interactions. Histology and ganglioside composition were examined in a natural brain tumour of the VM mouse strain. The tumour is distinguished from other metastatic tumour models because it arose spontaneously and metastasizes to several organs including brain and spinal cord after subcutaneous inoculation of tumour tissue in the flank. By electron microscopy, the tumour consisted of cells (15 to 20 μm in diameter) that had slightly indented nuclei and scant cytoplasm. The presence of smooth membranes with an absence of junctional complexes was a characteristic ultrastructural feature. No positive immunostaining was found for glial or neuronal markers. The total ganglioside sialic acid content of the subcutaneously grown tumour was low (12.6 ± 0.9 μg per 100 mg dry wt, n= 6 separate tumours) and about 70% of this was in the form of N-glycolylneuraminic acid. In contrast, the ganglioside content of the cultured VM tumour cells was high (248.4 ± 4.4 μg, n= 3) and consisted almost exclusively of N-acetylneuraminic acid. The ganglioside pattern of the tumour grown subcutaneously was complex, while GM3, GM2, GM1, and GD1a were the major gangliosides in the cultured tumour cells. This tumour will be a useful natural model for evaluating the role of gangliosides and other glycolipids in tumour cell invasion and metastasis. © 2001 Cancer Research Campaign http://www.bjcancer.co
Ultrathin compound semiconductor on insulator layers for high performance nanoscale transistors
Over the past several years, the inherent scaling limitations of electron
devices have fueled the exploration of high carrier mobility semiconductors as
a Si replacement to further enhance the device performance. In particular,
compound semiconductors heterogeneously integrated on Si substrates have been
actively studied, combining the high mobility of III-V semiconductors and the
well-established, low cost processing of Si technology. This integration,
however, presents significant challenges. Conventionally, heteroepitaxial
growth of complex multilayers on Si has been explored. Besides complexity, high
defect densities and junction leakage currents present limitations in the
approach. Motivated by this challenge, here we utilize an epitaxial transfer
method for the integration of ultrathin layers of single-crystalline InAs on
Si/SiO2 substrates. As a parallel to silicon-on-insulator (SOI) technology14,we
use the abbreviation "XOI" to represent our compound semiconductor-on-insulator
platform. Through experiments and simulation, the electrical properties of InAs
XOI transistors are explored, elucidating the critical role of quantum
confinement in the transport properties of ultrathin XOI layers. Importantly, a
high quality InAs/dielectric interface is obtained by the use of a novel
thermally grown interfacial InAsOx layer (~1 nm thick). The fabricated FETs
exhibit an impressive peak transconductance of ~1.6 mS/{\mu}m at VDS=0.5V with
ON/OFF current ratio of greater than 10,000 and a subthreshold swing of 107-150
mV/decade for a channel length of ~0.5 {\mu}m
Parkinsonism caused by adverse drug reactions: a case series
<p>Abstract</p> <p>Introduction</p> <p>Parkinsonism puts a high direct cost burden on both patient and caregiver. Several reports of drug-induced parkinsonism have been published, but to the best of our knowledge, there has not been any report of quinine or halothane inducing parkinsonism.</p> <p>Case presentation</p> <p>We describe two cases of parkinsonism possibly caused by adverse drug reaction to quinine in a 29-year-old black Nigerian woman and to halothane in a 36-year-old black Hausa (Nigerian) man who received it as general anaesthesia for appendicectomy in our teaching hospital.</p> <p>Conclusion</p> <p>These are two unusual cases of parkinsonism caused by adverse drug reactions to high-dose quinine and to halothane as general anaesthesia. We consider that these two cases are important in bringing this potential side-effect to the attention of both pharmacologists and primary care physicians as these are two of the most commonly used medications in our clinics. We conclude that parkinsonism should be included among the adverse drug reactions to high-dose quinine and halothane general anaesthetic.</p
Optical and HI properties of isolated galaxies in the 2MIG catalog. I. General relationships
We analyze empirical relationships between the optical, near infrared, and HI
characteristics of isolated galaxies from the 2MIG Catalog covering the entire
sky. Data on morphological types, K_S-, and B-magnitudes, linear diameters, HI
masses, and rotational velocities are examined. The regression parameters,
dispersions, and correlation coefficients are calculated for pairs of these
characteristics. The resulting relationships can be used to test the
hierarchical theory of galaxy formation through numerous mergers of cold dark
matter.Comment: 18 pages, 11 figures, 5 table
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