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This paper analyses the relationship between productive efficiency and online-social-networks (OSN) in Spanish telecommunications firms. A data-envelopment-analysis (DEA) is used and several indicators of business “social Media” activities are incorporated. A super-efficiency analysis and bootstrapping techniques are performed to increase the model's robustness and accuracy. Then, a logistic regression model is applied to characterise factors and drivers of good performance in OSN. Results reveal the company's ability to absorb and utilise OSNs as a key factor in improving the productive efficiency. This paper presents a model for assessing the strategic performance of the presence and activity in OSN. 相似文献
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Riccardo AccorsiAuthor Vitae Riccardo ManziniFausto MaranesiAuthor Vitae 《Computers in Industry》2014
The issue of material handling involves the design and operative control of warehousing systems (i.e., distribution centres), which allow matching vendors and demands, smoothing with seasonality, consolidating products and arranging distribution activities. Warehousing systems play a crucial role in providing efficiency and customer satisfaction. The warehouse design entails a wide set of decisions, which involve layout constraints and operative issues that seriously affect the performances and the overall logistics costs. 相似文献
55.
Two new optical single side band (OSSB) configurations for radio frequency (RF) transmission of data are proposed based on the structures that have been designed for baseband digital data transmission. The performances of these schemes are evaluated based on the relevant eye diagrams and bit error rate (BER). The proposed configurations are studied and analyzed mathematically. Eye diagrams and BER’s indicate an acceptable performance for the suggested structures. Feasible settings for the RF electrical power of the links are considered and the link performance for each setting is evaluated. A 4-dense wavelength division multiplexing (4-DWDM) link is considered for transmitting different types of data over a single mode fiber (SMF). Baseband digital data in the format of OSSB and RF-OSSB signals are transmitted over a 4-DWDM link. Furthermore, the link performance is considered for different electrical power settings of OSSB signal in order to achieve efficient transmission for DWDM network. 相似文献
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The nature of home automation is introduced. It is argued that end users should be able to define how the home system reacts to changing circumstances. Policies are employed as user-defined rules for how this should happen. The architecture of the Homer home automation system is briefly overviewed. The Homer policy system and the Homeric policy language it supports are explained. A technique is described for offline conflict analysis among policies (the analogue of the feature interaction problem). A substantial worked example shows how conflict detection is performed on a range of sample home policies. 相似文献
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Faruk Ugranl?Author VitaeEngin KaratepeAuthor Vitae 《Renewable & Sustainable Energy Reviews》2012,16(1):582-590
This paper presents different approaches to find out and address some rules for distributed generation (DG) integrated mesh type networks, which can be used in the management of future power systems. There are so many influencing factors of efficiency in the integration of DG that we need to analyze these influencing factors obviously. Hence, carefully planning plays a key role in tackling these challenges in the future power systems. In contrast to the majority of existing observations, we focus on the case where the underlying states are multiple and single DG allocations with changing conditions. In several previous studies, the best single bus has been investigated under the specified conditions. However, it follows from the results of this study that all issues concerning DG strongly depend on power network structure and DG locations, and it is worth to note that the best location changes with penetration levels. Also, it is observed that the all buses show different characteristics in terms of DG integrations under the different cases, moreover their optimum size and power factor are different. It means that optimum bus in a network changes with the conditions. On the other hand, the problematic buses can be occurred in voltage profile after the DG integration. As a result, an investigation of rule of thumb approach is performed for evaluation of performance enhancement of DG integrated meshed networks. The results are also used to discuss the integration of DG management strategies under various operating conditions. 相似文献
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Lei ChenAuthor Vitae Guangnan XingAuthor Vitae Yingjie XuAuthor VitaeXiaoxiang LiuAuthor Vitae Tuanjie ZhaoAuthor Vitae Junyi GaiAuthor Vitae 《Computers & Electrical Engineering》2012,38(1):3-10
Proteomics has been utilized as an effective approach to link phenotype and genome sequence, but effective strategies need to be explored to find target gene(s) from a great number of differentially expressed proteins (DEPs). Here, we present an integrated approach employing a range of methods and software tools including phenomics, proteomics, genomics and metabolomics to identify key responding proteins of the abnormal leaf and flower (alf) gene. The results showed alf involved in an extensively regulatory network among different pathways according to the proteomic and metabolomic profile of the alf near-isogenic lines. GLUTAMATE-1-SEMIALDEHYDE2,1-AMINOMUTASE (GSA) and PEPTIDYL-PROLYL CIS-TRANS ISOMERASE (PIN) located on the same region of ALF/alf locus were identified as key responding factors. Their functions from annotation are consistent to the performance of leaf shape and chlorophyll content of the alf mutant. The present study has demonstrated the effectiveness of the integrative “omics” strategy in improving detection of target gene(s). 相似文献