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991.
Organizations are increasingly turning to information technology (IT) to help them respond to unanticipated environmental threats and opportunities. In this paper, we introduce a systematic review of the literature on IT-enabled agility, helping to establish the boundary between what we know and what we don’t know. We base our review on a wide body of literature drawn from the AIS Basket of Eight IT journals, a cross-section of non-Basket journals, IT practitioner outlets, and premier international IS conferences. We review the use of different theoretical lenses used to investigate the relationship between IT and organizational agility and how the literature has conceptualized agility, its antecedents, and consequences. We also map the evolution of the literature through a series of stages that highlight how researchers have built on previous work. Lastly, we discuss opportunities for future research in an effort to close important gaps in our understanding.  相似文献   
992.
We report on an in‐depth corpus linguistic study on ‘multiple views’ terminology and word collocation. We take a broad interpretation of these terms, and explore the meaning and diversity of their use in visualisation literature. First we explore senses of the term ‘multiple views’ (e.g., ‘multiple views’ can mean juxtaposition, many viewport projections or several alternative opinions). Second, we investigate term popularity and frequency of occurrences, investigating usage of ‘multiple’ and ‘view’ (e.g., multiple views, multiple visualisations, multiple sets). Third, we investigate word collocations and terms that have a similar sense (e.g., multiple views, side‐by‐side, small multiples). We built and used several corpora, including a 6‐million‐word corpus of all IEEE Visualisation conference articles published in IEEE Transactions on Visualisation and Computer Graphics 2012 to 2017. We draw on our substantial experience from early work in coordinated and multiple views, and with collocation analysis develop several lists of terms. This research provides insight into term use, a reference for novice and expert authors in visualisation, and contributes a taxonomy of ‘multiple view’ terms.  相似文献   
993.

Unit commitment problem (UCP) aims at optimizing generation cost for meeting a given load demand under several operational constraints. We propose to use fuzzy reinforcement learning (RL) approach for efficient and reliable solution to the unit commitment problem. In particular, we cast UCP as a multiagent fuzzy reinforcement learning task wherein individual generators act as players for optimizing the cost to meet a given load over a twenty-four-hour period. Unit commitment task has been fuzzified, and the most optimal unit commitment solution is generated by employing RL on this fuzzy multigenerator setup. Our proposed multiagent RL framework does not assume any a priori task or system knowledge, and the generators gradually learn to produce most optimal output solely based on their collective generation. We look at the UCP as a sequential decision-making task with reward/penalty to reduce the collective generation cost of generators. To the best of our knowledge, ours is a first attempt at solving UCP by employing fuzzy reinforcement learning. We test our approach on a ten-generating-unit system with several equality and inequality constraints. Simulation results and comparisons against several recent UCP solution methods prove superiority and viability of our proposed multiagent fuzzy reinforcement learning technique.

  相似文献   
994.
Nehra  Vibha  Sharma  Ajay K.  Tripathi  Rajiv K. 《Wireless Networks》2019,25(6):3689-3700
Wireless Networks - This paper presents a naked mole rat (NMR) inspired energy efficient protocol for heterogeneous wireless sensor network. NMR uses strategic deployment among three types of nodes...  相似文献   
995.
Due to the widespread popularity and usage of Internet of things (IoT)‐enabled devices, there is an exponential increase in the data traffic generated from these IoT devices. Most of these devices communicate with each other using heterogeneous links having constraints such as latency, throughput, and interference from concurrent transmissions. This results in an extra burden on the underlying communication infrastructure to manage the traffic within these constraints between source and destination. However, most of the existing applications use different Transmission Control Protocol (TCP) variants for traffic management between these devices and are dependent on the stage of the sender, irrespective of the application types and link characteristics. Each operating system (OS) has different TCP variant for all applications, irrespective of path characteristics. Hence, a single TCP variant cannot select the best suitable link, which results in degradation in throughput compared to the existing default. Moreover, it cannot use the full capacity of the available link for different applications and network links, especially in heterogeneous network such as IoT. To cope up with these challenges, in this paper, we propose an Adaptive and Dynamic TCP Interface Architecture (ADYTIA). ADYTIA allows the usage of different TCP variants based on application and link characteristics, irrespective of the physical links of the entire path. It allows the usage of different TCP variants based on their design principle across heterogeneous technologies, platforms, and applications. ADYTIA is implemented on NS‐2 and Linux kernel for real testbed experiments. Its ability to select the best suitable TCP variant results in 20% to 80% improvement in throughput compared with the existing default and single TCP variant on Linux and Windows.  相似文献   
996.
Wireless communication systems have gained huge attraction from research community, industrial, and academic field due to their significant impact on improving the communication efficiency, ease of deployment, and cost‐effective solution for real‐time communication. In this field of wireless communication, cellular communications have grown rapidly due to their daily usages and advantages. This increased demand of cellular communication systems has led to the evolution of 3G, 4G, and 5G communication systems, which in turn demands for higher efficiency and better bandwidth utilization. Due to heavy usage of network communication, multiple users may cause interference which subsequently may lead to the performance degradation which could be addressed using multiuser detection scheme. However, several schemes have been introduced for improving the system performance, but multiple access (MA) still remains a challenging task. Hence, in this work, we present a novel approach called Spatial Log‐Likelihood Multiuser Detection and Interference Cancelation (SLLR‐MDIC) that uses interleaving division multiple access (IDMA) to improve the communication and developed a multiuser detection approach using spatial log‐likelihood ratios. Further, we have developed orthogonal frequency‐division multiple access (OFDM)–IDMA‐based interference cancelation scheme in multiple access to improve the performance using rake receiver based approach. The performance of SLLR‐MDIC scheme is compared with existing techniques of multiuser detection in terms of bit‐error rate (BER) and symbol error rate (SER). The experimental analysis shows that proposed approach achieves improved performance when compared with existing techniques.  相似文献   
997.
Numerous research articles exist for backbone formation in wireless networks; however, they cannot be applied straightforward in cognitive radio network (CRN) due to its peculiar characteristics. Since virtual backbone has many advantages such as reduced routing overhead, dynamic maintenance, and fast convergence speed, we intend to propose a backbone formation protocol in CRN. In this paper, we propose a tree‐based backbone formation protocol along with its maintenance. Our protocol is based on non‐iterative approach, thus leading towards limited message overhead and faster convergence speed. The proposed algorithm first forms the tree by maintaining the parent‐child relationship, and second, the parent nodes are connected together to form the virtual backbone. In the end, we evaluate the performance our protocol through extensive simulations.  相似文献   
998.
Photonic Network Communications - This paper depicts the design of 0.55 Tb/s heterogeneous Flexi-rate Nyquist-wavelength division multiplexed (Nyquist-WDM) Superchannel. Here, for the...  相似文献   
999.
In this article, a small‐printed Bluetooth/LTE/UWB/X‐band/Ku‐band monopole antenna with high rejection triple band‐notch is presented. Notched bands include WiMAX (IEEE802.16 3.30‐3.80 GHz), WLAN IEEE802.11a/h/j/n (5.15‐5.35 GHz, 5.25‐5.35 GHz, 5.47‐5.725 GHz, and 5.725‐5.825 GHz), and downlink satellite system (7.1‐7.9 GHz). By including inverted T‐shaped stub and etching two C‐shaped slots on the radiating patch, triple band‐notch function is obtained with measured high band rejection (VSWR = 14.59 at 3.69 GHz, VSWR = 39.40 at 5.42 GHz, and VSWR = 6.43 at 7.57 GHz) and covers a UWB useable fractional bandwidth of 157.75% (2.285‐19.35 GHz = 17.065 GHz). Reconfigurable characteristics are obtained using PIN diodes, which control the individual notched bands. Proposed antenna is printed on Rogers RT/duroid5880 substrate with compact dimensions of 20 × 22 mm2. Proposed antenna finds its applications for Bluetooth, LTE, UWB, other multiple wireless applications for close range radar (8‐12 GHz) in X‐band, and satellite communication in Ku‐Band with omnidirectional pattern in H‐plane.  相似文献   
1000.
Resurgence of nuisance benthic algae in the Great Lakes, despite substantial efforts to reduce phosphorus loading, has stimulated renewed interest in exploring the diverse drivers of near-shore water quality. Interestingly, broad similarity in the underlying causes of shore fouling by benthic algae in Lakes Ontario, Erie, and Michigan appear to contrast with Lake Huron where system productivity and dreissenid abundance are lower. While total phosphorus was the primary predictor of chlorophyll concentrations (70–90% of variation) in the water column, we identified a series of spatial patterns that underpin this relationship (up to 28% of variation) and which integrate catchment processes, tributary influences, shoreline complexity, and distance from shore. Dreissenid mussels were the most important predictors of benthic algae cover and biomass in our models, explaining between 20 and 52% of variation. Spatial patterns explained an additional 21–48% of the variation in benthic algae cover and biomass and highlight the importance of site-specific spatial heterogeneity in benthic algae growth. Our results are consistent with the nearshore shunt hypothesis, wherein higher algal cover and biomass coincided with higher mussel density and biomass, although correlative effects with lake depth and loss of algal and mussel biomass due to physical disturbance must also be considered. These results underscore the difficulty associated with identifying the potential drivers of nearshore water quality as the diverse processes of nutrient loading, changes in catchment land use, and ecosystem change associated with invasion by dreissenids all vary in relative influence over a range of spatial scales.  相似文献   
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