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Simultaneity of Synchronization and Antisynchronization in a Class of Chaotic Systems
Get PDFIn this paper, a new synchronization phenomenon, that is, the simultaneity of synchronization and antisynchronization, is investigated for a class of chaotic systems. First, for a given chaotic system, necessary and sufficient conditions for the simultaneity of synchronization and antisynchronization are proved. Then, based on these conditions, all solutions of such synchronization phenomenon for a given chaotic system are derived. After that, physical controllers that are not only simple but also implementable are designed to realize the simultaneity of synchronization and antisynchronization in the above system. Finally, illustrative examples based on numerical simulations are used to verify the validity and effectiveness of the above theoretical results
Stabilization of chaotic systems with both uncertainty and disturbance by the UDE-based control method
No full textThis paper investigates the stabilization of a class of chaotic systems with both model uncertainty and external disturbance. By combining the dynamic feedback control method, and the uncertainty and disturbance estimator (UDE)-based control method, a new UDE-based control method is developed. By using this method, the system stabilization can be achieved by three steps. Illustrative examples using numerical simulations verify the soundness and effectiveness of the proposed method
Current trends in the pharmacotherapy of cataracts
Get PDFCataracts, one of the leading causes of preventable blindness worldwide, refers to lens degradation that is characterized by clouding, with consequent blurry vision. As life expectancies improve, the number of people affected with cataracts is predicted to increase worldwide, especially in low-income nations with limited access to surgery. Although cataract surgery is considered safe, it is associated with some complications such as retinal detachment, warranting a search for cheap, pharmacological alternatives to the management of this ocular disease. The lens is richly endowed with a complex system of non-enzymatic and enzymatic antioxidants which scavenge reactive oxygen species to preserve lens proteins. Depletion and/or failure in this primary antioxidant defense system contributes to the damage observed in lenticular molecules and their repair mechanisms, ultimately causing cataracts. Several attempts have been made to counteract experimentally induced cataract using in vitro, ex vivo, and in vivo techniques. The majority of the anti-cataract compounds tested, including plant extracts and naturally-occurring compounds, lies in their antioxidant and/or free radical scavenging and/or anti-inflammatory propensity. In addition to providing an overview of the pathophysiology of cataracts, this review focuses on the role of various categories of natural and synthetic compounds on experimentally-induced cataracts
Analysis of Bacterial Loads in Houston Indoor Air.
Get PDFHouse dust is a complex matrix containing organic and inorganic content with a good percentage of microorganisms. Microorganism’s growth and survival in dust depends on available moisture level. Microbial origin in dust depends on sources other than dust. On average people spend approximately 90% of their time in indoor environment. Therefore, they are continuously exposed to microbes in dust. Based on the size and volume of dust particles the microbes get access to human lungs via airways. Based on previous research; culture dependent studies indicate that Penicillium, Aspergillus, Cladosporium are in abundance is house dust along with 20 other fungal genera. While bacterial flora in house dust is dominated by gram positive bacteria such as Staphylococcus, Corynebacterium, and Lactococcus etc. Culture-independent studies demonstrate that higher diversity of fungal and bacterial species, approximately 500-1000 species is prevalent in house dust. Microbial abundance in house dust can exceed up to 109 cells/g dust, depending on techniques employed, different environmental conditions and type of indoor environment, among other factors. In current study filter dust samples were collected from ten households from Houston by volunteers by following the devised protocol and assessed for diversity and bacterial abundance in indoor air. Samples were transported and stored in labs before processing. Samples were processed by following two techniques i.e. Cut sample technique and Serial dilution. The bacterial colonies were grown on three different media i.e. Luria-Bertani , Eosin Methylene blue and MacConkey agar. The pure colonies were counted with serial dilution technique . The next step was bacterial identification. Microbes were identified using Morphological characteristics, Gram staining, Oxidase, Catalase test and Biolog technique. Ten bacterial strains were identified by using Biolog technique on the basis of their metabolic potential. All bacteria isolated and identified were found to be Gram positive in nature. Bacillus cereus was selected as an organism of interest because of its pathogenicity against humans. Therefore, ATTC strain of B. cereus was obtained and growth kinetics and biofilm production was compared to investigate the survival potential of surrogate bacteria when exposed to lead challenge (0.5ppm,10ppm, 25ppm and 100ppm). The statistical analysis indicated higher growth rate and biofilm production of B.cereus isolated from indoor filter dust sample when exposed to different concentrations of lead (Pb) in comparison to an ATTC strain of B.cereus
People Analytics and Disruptive Technologies are Transforming Human Resources Roles
Get PDFHuman Resources Information Systems that collect, store, and analyze people data are beginning to view the role of people analytics and other related technologies favorably as they provide new, timely and objective insights which aid in bringing about a transformational change in the roles of HR. People analytics is thus an excellent platform for HR to achieve its long awaited ‘Strategic Partner’ role. Organizations of all sizes and types are adopting and adapting to people analytics. Several well-known companies have recently demonstrated the benefits of using people analytics for HR functions. However, people analytics is not without roadblocks of unethical or illegal use of people data. Additionally, shortages of qualified staff able to adapt to the increasingly technology driven workplace will slow down HR\u27s transformation. This paper studies the role of people analytics in transforming HR. It examines some real-life organizational examples in people analytics, and challenges for its widespread adoption. It also discusses the future of this burgeoning trend in HR, as well as potential applications of the other disruptive technologies
Business Intelligence Illustrated Using Crime Data as an Instructional Tool
Get PDFIn the Management Information Systems classroom, faculty are encouraged to provide a student focused learning environment that focuses on utilizing business and industry practices as tools. Examples should incorporate concepts which students can readily comprehend. With this in mind, the City of Houston Uniform Crime Report Statistics spreadsheet and database data is being utilized in a College of Business MIS program. In this paper, examples will be described which provide illustrations showing how this ever changing Crime Report data provides an instructional landscape that students can readily recognize and which can also be used as a tool that reinforces learning. Varying examples, utilizing business and industry practices, will be shown. As examples, crime data will be shown to demonstrate concepts in an assortment of courses taught in the MIS discipline such as the Management of Information Systems course, Microcomputer Applications course, Introduction to Database course, and the Business Intelligence course
Simulation and analysis of the carrying capacity for road networks using a grid-based approach
Get PDFThe number of vehicles that a road network can carry is limited. When the limit is exceeded, the network system is not able to function effectively. In this paper, an updated cellular automaton model for grid networks with all-way stop-controlled intersections is proposed to simulate the network level critical density and carrying capacity under different conditions, which essentially indicates the limit number of vehicles that the network can handle before going into gridlock. In the proposed model, two update rules, including lane-changing and the longitudinal location update, are adopted to describe the vehicle\u27s movements on road segments according to the driving condition on the road and the vehicle\u27s direction in the downstream intersection. The vehicle\u27s movements in intersection areas are prioritized based on vehicle\u27s position, so as to prevent collisions within the intersection area. The simulation results show that an increase in network size is able to expand the carrying capacity of a road network, whereas the expansion rate is lower than the change rate in the network size. The carrying capacity is also associated with the structure of road network. The carrying capacity is inversely proportional to the number of intersections, and proportional to the length of the road in the network. Also, optimizing the origin-destination (O-D) distribution can increase the carrying capacity of an urban road network
Analysis of factors contributing to the severity of large truck crashes
Get PDFCrashes that involved large trucks often result in immense human, economic, and social losses. To prevent and mitigate severe large truck crashes, factors contributing to the severity of these crashes need to be identified before appropriate countermeasures can be explored. In this research, we applied three tree‐based machine learning (ML) techniques, i.e., random forest (RF), gradient boost decision tree (GBDT), and adaptive boosting (AdaBoost), to analyze the factors contributing to the severity of large truck crashes. Besides, a mixed logit model was developed as a baseline model to compare with the factors identified by the ML models. The analysis was performed based on the crash data collected from the Texas Crash Records Information System (CRIS) from 2011 to 2015. The results of this research demonstrated that the GBDT model outperforms other ML methods in terms of its prediction accuracy and its capability in identifying more contributing factors that were also identified by the mixed logit model as significant factors. Besides, the GBDT method can effectively identify both categorical and numerical factors, and the directions and magnitudes of the impacts of the factors identified by the GBDT model are all reasonable and explainable. Among the identified factors, driving under the influence of drugs, alcohol, and fatigue are the most important factors contributing to the severity of large truck crashes. In addition, the exists of curbs and medians and lanes and shoulders with sufficient width can prevent severe large truck crashes
Symbolically Annihilating Female Police Officer Capabilities: Cultivating Gendered Police Use of Force Expectations?
No full textThis first step cultivation analysis examines the quantity, temporal dynamics, and stance of municipal police officer use of force depictions based on the gender of the officer. The 112 theatrically released films that comprise the core cop film genre were systematically identified. Subsequently, a population of 468 police use of force scenes was identified to serve as the units of analysis for this study. Findings revealed male officer use of force scenes appeared across all 40 years of films. Female officer use of force scenes, however, were highly restricted to specific films, years, and often dwarfed by male scenes within films. Lone female officer use of force scenes saw their highest representation in the 1980s but declined in the 1990s and 2000s, becoming increasingly dependent on a male officer’s presence. Implications of such patterns are discussed as well as potential second step cultivation studies