Showing papers by "Nicholls State University published in 2017"

Simultaneous Wireless Information and Power Transfer: Technologies, Applications, and Research Challenges

Abstract: Energy efficiency will play a crucial role in future communication systems and has become a main design target for all 5G radio access networks. The high operational costs and impossibility of replacing or recharging wireless device batteries in multiple scenarios, such as wireless medical sensors inside the human body, call for a new technology by which wireless devices can harvest energy from the environment via capturing ambient RF signals. SWIPT has emerged as a powerful means to address this issue. In this article, we survey the current architectures and enabling technologies for SWIPT and identify technical challenges to implement SWIPT. Following an overview of enabling technologies for SWIPT and SWIPT-assisted wireless systems, we showcase a novel SWIPT-supported power allocation mechanism for D2D communications to illustrate the importance of the application of SWIPT. As an ending note, we point out some future research directions to encourage and motivate more research efforts on SWIPT.

Assessing coastal wetland vulnerability to sea-level rise along the northern Gulf of Mexico coast: Gaps and opportunities for developing a coordinated regional sampling network.

Abstract: Coastal wetland responses to sea-level rise are greatly influenced by biogeomorphic processes that affect wetland surface elevation. Small changes in elevation relative to sea level can lead to comparatively large changes in ecosystem structure, function, and stability. The surface elevation table-marker horizon (SET-MH) approach is being used globally to quantify the relative contributions of processes affecting wetland elevation change. Historically, SET-MH measurements have been obtained at local scales to address site-specific research questions. However, in the face of accelerated sea-level rise, there is an increasing need for elevation change network data that can be incorporated into regional ecological models and vulnerability assessments. In particular, there is a need for long-term, high-temporal resolution data that are strategically distributed across ecologically-relevant abiotic gradients. Here, we quantify the distribution of SET-MH stations along the northern Gulf of Mexico coast (USA) across political boundaries (states), wetland habitats, and ecologically-relevant abiotic gradients (i.e., gradients in temperature, precipitation, elevation, and relative sea-level rise). Our analyses identify areas with high SET-MH station densities as well as areas with notable gaps. Salt marshes, intermediate elevations, and colder areas with high rainfall have a high number of stations, while salt flat ecosystems, certain elevation zones, the mangrove-marsh ecotone, and hypersaline coastal areas with low rainfall have fewer stations. Due to rapid rates of wetland loss and relative sea-level rise, the state of Louisiana has the most extensive SET-MH station network in the region, and we provide several recent examples where data from Louisiana's network have been used to assess and compare wetland vulnerability to sea-level rise. Our findings represent the first attempt to examine spatial gaps in SET-MH coverage across abiotic gradients. Our analyses can be used to transform a broadly disseminated and unplanned collection of SET-MH stations into a coordinated and strategic regional network. This regional network would provide data for predicting and preparing for the responses of coastal wetlands to accelerated sea-level rise and other aspects of global change.

Topology Control for Building a Large-Scale and Energy-Efficient Internet of Things

Abstract: The IoT is one of the most significant recent innovations in information technologies, which has attracted extensive attention from both industry and academia due to its potential impact on various networking-related fields. The rapid development in IoT technologies has resulted in widespread application of this emerging networking paradigm in various disciplines. On the other hand, IoT faces some challenges that must be fully dealt with, among which scalability and energy efficiency are two critical issues. Topology control offers a promising approach to designing a large-scale and energy-efficient IoT. In this article, we first present a taxonomy of currently available topology control algorithms, and then propose a systematic approach to topology construction in IoT to achieve scalability and energy efficiency. We intend to provide researchers and practitioners with a big picture of the current research status in this area, and hope that this article may motivate more researchers to participate in largescale IoT design, development, and deployment.

DTD: A Novel Double-Track Approach to Clone Detection for RFID-Enabled Supply Chains

Abstract: Toward improving the traditional clone detection technique whose performance may be affected by dynamic changes of supply chains and misread, we present a novel and effective clone detection approach, termed double-track detection, for radio frequency identification-enabled supply chains. As part of a tag’s attributes, verification information is written into tags so that the set of all verification information in the collected tag events forms a time series sequence. Genuine tags can be differentiated from clone tags due to the discrepancy in their verification sequences which are constructed as products flow along the supply chain. The verification sequence together with the sequence formed by business actions performed during the supply chains yield two tracks which can be assessed to detect the presence of clone tags. Theoretical analysis and experimental results show that our proposed mechanism is effective, reasonable, and has a relatively high clone detection rate when compared with a leading method in this area.

Network Coding in Relay-Based Device-to-Device Communications

Abstract: Device-to-device (D2D) communications has been realized as an effective means to improve network throughput, reduce transmission latency, and extend cellular coverage in 5G systems. Network coding is a well established technique known for its capability to reduce the number of retransmissions. In this article, we review stateof- the-art network coding in relay-based D2D communications, in terms of application scenarios and network coding techniques. We then apply two representative network coding techniques to dual-hop D2D communications and present an efficient relay node selecting mechanism as a case study. We also outline potential future research directions, according to the current research challenges. Our intention is to provide researchers and practitioners with a comprehensive overview of the current research status in this area and hope that this article may motivate more researchers to participate in developing network coding techniques for different relay-based D2D communications scenarios.

Modeling of microfluidic bio-solar cell using microalgae through multiphysics platform: A greener approach en route for energy production

Abstract: Due to the growing energy demands and increased concern over environmental deterioration and energy climate catastrophe, bio-energy based mechanisms had gained interest over recent years and had attained acknowledgment as the “greener” energy self-sustainable technologies of the future. A new micro-fluidic bio-solar cell modeling and their integration using COMSOL multi-physics have been proposed in order to convert solar energy into bioelectricity. Synechocystis PCC6803 is used as the microbial source due to its electrical property for generating electrons through an anodic chamber. Using COMSOL multi-physics platform, the microfluidic bio-solar cell was designed with five functioning layers. Each layer is been assigned with the suitable electrical/electrode properties of the polymer and the anodic chamber layer been assigned with the properties of the microalgae. Finally, the microfluidic bio-solar cell was modeled to create interfaces between optical and electrical physics in order to determine their material transport, heat transfer, electrochemical behavior, current density and voltage distribution behavior of the microfluidic bio-solar cell. The open circuit voltage of about 0.42 V is been obtained with 80% of absorption capacity. This modeling can be further developed into an extensible bio-solar panel by fabricating it using a microfluidic chamber for further application enhancement, which can replace inorganic solar cells with bio-solar cells for an eco-friendly environment with less production cost.

Semantic Web Service Composition in Big Data Environment

Abstract: The widespread deployment of web services and rapid development of big data applications bring in new challenges to web service compositions in the context of big data. The large number of web services processing a huge amount of diverse data together with the complex and dynamic relationships among the services require automatic composition of semantic web services to be performed quickly, thereby demanding more efficient service composition algorithms. In this paper, we investigate the issue of web service composition in big data environments by proposing novel composition algorithms with low time-complexity. Specifically, we decompose the service composition into three stages - construction of parameter expansion graphs, transformation of service dependence graphs, and backtracking search for service compositions. Based on the parameter expansion strategies, we then propose two efficient semantic web service composition algorithms and analyze their time complexity. We also conduct comparison experimentally to evaluate the efficiency of the algorithms and validate their effectiveness using a big data (service composition) set.

Anaerobic Degradation of Petroleum Hydrocarbons in Sediments

Abstract: The conventional approach to bioremediation of petroleum hydrocarbons is based on aerobic processes. Anaerobic bioremediation has been tested in only a very few cases and is still considered experimental. The currently practiced conventional in situ biorestoration of petroleum-contaminated soils and groundwater relies on the supply of oxygen to the subsurface to enhance natural aerobic processes to remediate the contaminants. However, anaerobic microbial processes can be significant in oxygen-depleted subsurface environments that are contaminated with petroleum-based compounds. The theme of this chapter is the bioremediation of petroleum hydrocarbons present in contaminated sites under anaerobic conditions. This chapter discusses various indigenous anaerobic microorganisms present in contaminated sites that can degrade many individual organic compounds present in petroleum hydrocarbons. An experimental system to evaluate the ability of microorganisms to degrade petroleum hydrocarbons under a variety of electron acceptor conditions is discussed.

Genetic variation and biogeography of the spotted gar Lepisosteus oculatus from core and peripheral populations.

Abstract: The spotted gar (Lepisosteus oculatus) shows a disjunct natural distribution, with a core population extending from the central Mississippi River Basin to the U.S. gulf coast and a peripheral population in the southern Great Lakes Basin. Despite significant conservation concerns for this species in the Great Lakes watersheds where it occurs, few genetic examinations and comparisons of these populations have been performed. We investigated inter- and intrapopulational variation in several mitochondrial genetic markers (cytochrome oxidase subunit I, COI; cytochrome oxidase subunit II, COII; and 16S rRNA, 16S) from spotted gars taken from core and peripheral populations. Genetic diversity was highest in the Mississippi River Basin and lowest in the Great Lakes Basin, while the Nueces River Basin (Texas) population showed the greatest level of divergence from other populations. Average genetic distance among core and peripheral populations was over an order of magnitude less than that seen between L. oculatus and its sister species, the Florida gar (L. platyrhincus), although a significant correlation was found between genetic and geographical distance in L. oculatus. Genetic divergence in spotted gars is likely to be related to a combination of geographic isolation and founder effects associated with recent colonization following glacial retreat. Despite its apparent lack of significant genetic differentiation or haplotype diversity, the Great Lakes population of spotted gars has previously been shown to be a unique component of the species, and additional studies are needed to determine the genetic mechanisms underlying regional adaptations as well as potential morphological differentiation among spotted gar populations.

IP Flow Mobility in the Industry: From An Economic Perspective

Abstract: The popularity of social media together with the advancement of mobile Internet applications enabling the uploading of data plays a dominant role in the entire Internet traffic. IP flow mobility (IFOM) is proposed as an effective means to enhance the system capacity by offloading data from the cellular network to WiFi or Femtocells or other complementary networks. Although IFOM has been extensively investigated during the past few years, most of these studies, however, are concerned with IFOM technical issues only; little work regarding the IFOM application has been done from the service providers’ perspective. Unlike previous research, in this paper, we address the economic issue involved with the IFOM technology. Specifically, competition among multiple service providers supporting or not supporting IFOM are explored, and a game model for the competition is developed. The Nash equilibrium for the game model is then analyzed. Based on the analysis, an algorithm for Nash equilibrium computation is proposed. Also, numerical experiments are conducted to determine the factors that affect the market share and profit of the service providers. We believe that this research paper will shed light on service providers for the promotion and application of IFOM technology.

Observations of Raccoon (Procyon lotor) Predation on the Invasive Maculata Apple Snail (Pomacea maculata) in Southern Louisiana

Abstract: We used camera traps to determine which predators were responsible for depredated Pomacea maculata (Maculata Apple Snail) shells at 2 different study sites. Evidence of predation at these sites included operculums near the shells with a small amount of flesh attached and shells accumulating a meter or more from the water's edge with no evidence of recent flooding. In both locations, the most frequently observed potential predators were Procyon lotor (Raccoon), which was the only species directly observed capturing and eating Apple Snails.

When D2D Meets Network Coding: A Tutorial Case Study

Abstract: As one of the core technologies for the future 5G communications, device-to-device (D2D) communication is known to be effective in enhancing spectrum efficiency and improving network throughput. While substantial progress has been made regarding D2D communications in various applications, most of the studies, however, focus on the single-hop D2D communication scenario, leaving the multi-hop D2D communication scenario inadequately investigated. Considering the multi-hop D2D communications are extremely useful in extending the communication range between two devices, and when D2D meets network coding, the potentials of both technologies can be fully unlocked, in this article, we present a tutorial case study on the long-distance D2D communication protocol in which multi-hop data transmissions are enhanced by network coding. We investigate four representative scenarios experimentally to demonstrate the performance gain of applying network coding to D2D communications. Our intention is to provide an in-depth study showing how network coding can be essentially beneficial to multi-hop D2D communications, and to encourage additional research in this area forthcoming.

Hydrological Responses to Channelization and The Formation of Valley Plugs and Shoals

Abstract: Rehabilitation of floodplain systems focuses on restoring interactions between the fluvial system and floodplain, however, there is a paucity of information on the effects of valley plugs and shoals on floodplain hydrological processes. We investigated hydrologic regimes in floodplains at three valley plug sites, two shoal sites, and three unchannelized sites. Valley plug sites had altered surface and sub-surface hydrology relative to unchannelized sites, while only sub-surface hydrology was affected at shoal sites. Some of the changes were unexpected, such as reduced flood duration and flood depth in floodplains associated with valley plugs. Our results emphasize the variability associated with hydrologic processes around valley plugs and our rudimentary understanding of the effects associated with these geomorphic features. Water table levels were lower at valley plug sites compared to unchannelized sites, however, valley plug sites had a greater proportion of days when water table inundation was above mean root collar depth than both shoal and unchannelized sites as a result of lower root collar depths and higher deposition rates. This study has provided evidence that valley plugs can affect both surface and sub-surface hydrology in different ways than previously thought and illustrates the variability in hydrological responses to valley plug formation.

Variability in Gull-Billed Tern (Gelochelidon nilotica) Breeding Parameters at the Isles Dernieres Barrier Islands Refuge, Louisiana, USA

Abstract: . Gull-billed Terns (Gelochelidon nilotica) have historically demonstrated variability in nest-site selection and reproductive success throughout their breeding range. However, few studies have investigated the breeding parameters of Gull-billed Tern populations on barrier islands in the northern Gulf of Mexico, USA. The main objective of this study was to investigate annual variability of breeding population size, hatching success, and causes of nest failure during eight breeding seasons (2009–2016). Annual variation was observed in colony sizes (Range = 1–68 nests), colony locations (among five islands), and hatching success (0–93%). Mean hatching success was 56% and flooding was the main cause of failure, accounting for 64% of all failed nests. Additionally, nest site habitat characteristics were compared between successful and unsuccessful Gull-billed Tern nests. Nest substrate composition differed between successful and failed nests, and successful nests were also associated with higher eleva...

Modeling and analysis for admission control of M2M communications using network calculus

Abstract: Machine-to-machine (M2M) communications and applications are expected to be a significant part of the next generation 5G networks. While there have been a large amount of research studies with respect to radio resource management, load balancing, and devices grouping for M2M communications, few of them has addressed the issue of admission control. In this paper, we propose a new admission control model for M2M communications, which classifies all M2M requests into delay-sensitive and delay-tolerant first, and then aggregates all delay-tolerant requests, aiming to reduce the number of requests from devices to base stations. An admission control algorithm based on this model is devised to prevent congestion and to improve the quality of services, and a network calculus based performance-analyzing technique is developed for this model. Both theoretical analyses and simulation results show that the proposed model is feasible and valid.

Ballots, Bribes, and Brand-Name Political Capital

Abstract: Campaign effort is allocated towards resources that increase voter support the most for the marginal effort. A model is developed for the derived demand for investment in brand name and voter persuasion and for votes bought outright. We see that a secret ballot increases the cost of monitoring paid voters and changes the relative prices for obtaining voter support through bribery and investment in brand name capital, increasing the demand for campaign or brand-name-induced capital. Alternately, restrictions on new spending on brand-name political capital increase the demand for votes gained through direct bribery, treating and conveyance of voters to the polls, while at the same time increase the relative value of incumbency, of existing brand-name political capital. The model we develop is used to examine restrictions on spending and on brand-name investment in candidates and the effects of such spending limits (and limits on campaign contributions) on the demand for additional votes gained by vote buying, treating and conveyance of voters to the polls.

Basqueing on the bayou: conflicting visions of authenticity in Julio Medem’s Vacas and Benh Zeitlin’s Beasts of the Southern Wild

Abstract: This article examines a similar use of bovine vision as an act of looking at a seemingly authentic Basque and bayou identity in, respectively, Julio Medem’s Vacas and Benh Zeitlin’s Beasts of the Southern Wild. Central to both these films is a similar dichotomy between masculinity and femininity as the feminine, particularly the mother figure, is simultaneously mythologized and threatened by a masculinity tied to essential identity. Both films also attempt to suture historical debates regarding racial purity (or lack thereof) and class struggle within their own self-mythologizations. Additionally, both films centralize those discussions around a binary between rural/natural and urban/social as means of addressing the dichotomy of myth versus historical authenticity. However, where Beasts asserts that a wild authenticity can be achieved by returning to a pre-social state, Vacas deconstructs any idea of a real Basque identity. What this article shows are the high stakes that come with representing a...