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On the convergence of two-dimensional fuzzy Volterra-Fredholm integral equations by using Picard method
Get PDFIn this paper we prove convergence of the method of successive approximations used to approximate the solution of nonlinear two-dimensional Volterra-Fredholm integral equations and define the notion of numerical stability of the algorithm with respect to the choice of the first iteration. Also we present an iterative procedure to solve such equations. Finally, the method is illustrated by solving some examples
Heat and Mass Transfer in MHD Micropolar Fluid in The Presence of Diffusion Thermo and Chemical Reaction
Get PDFThis work is devoted to investigating the influence of diffusion thermo effect on hydromagnetic heat and mass transfer oscillatory flow of a micropolar fluid over an infinite moving vertical permeable plate in a saturated porous medium in the presence of transverse magnetic field and chemical reaction. The dimensionless equations are solved analytically using perturbation technique. The effects of the various fluid flow parameters entering into the problem on the velocity, microrotation, temperature and concentration fields within the boundary layer are discussed with the help of graphs. Also the local skin-friction coefficient, the wall couple stress coefficient, and the rates of heat and mass transfer coefficients are derived and shown in graphs. Comparison of the obtained numerical results is made with existing literature and is found to be in good agreement
An Advanced Collusion Attack against User Friendship Privacy in OSNs
No full textOnline Social Networks (OSNs) are providing a variety of applications for human users to interact with families, friends and even strangers. One of such applications, friend search engine, which allows the general public to query individual users\u27 friend list, is gaining popularity recently. However, without proper design, this application may disclose users\u27 private relationship information. In this paper, we propose an advanced collusion attack, where a victim user\u27s friendship privacy setting can be compromised through a carefully designed query sequence coordinately launched by multiple malicious requstors. The effect of the proposed collusion attack is validated through synthetic social network data sets. In addition, the analysis of such advanced collusion attacks will also benefit the future design of more robust privacy preserving friend search engine in OSNs
Objective-driven and Pareto Front analysis: Optimizing time, cost, and job-site movements
No full textFinding the optimized trade-off relationship between cost and time, two important objectives of construction projects, helps project managers and their teams select a more suitable schedule for a given project. This trade-off relationship can roughly be estimated using past and cumulative knowledge, but since the early 1970s, researchers have been working on a systematic and mathematical solution to define this relationship more accurately. These researchers have used different optimization techniques such as the genetic algorithm (GA), ant colony, and fuzzy logic to further explore the relationship. In the present paper, the authors have used their previously introduced construction schedule generator algorithm to present graphical relationships between pre-defined objectives of schedule optimizations. The process starts with developing construction schedules from the project\u27s Building Information Model (BIM) as part of the input along with resource data. Then the process continues with optimization of all developed construction schedules according to the two mentioned objectives along with the introduced job-site movement objective, which mathematically helps the sequence of installation be more logical and practical. Finally generation of a 3D space for all the created and calculated construction schedules in the form of a 3D solution cloud point. These 3D construction schedules show solution cloud points and three Pareto Fronts for the given project
Square or not Square--That’s the Question!
Get PDFBackground: Most heavy metals from industrial catalysts are harmful to human body; however, to function normally, the human body does need traces of essential metal cofactors. Histidine is one of the nine essential amino acids to the human body, and cobalt(II) ion is cost effective and is known to be less toxic to the body. Methods: This project investigates the binding reactions between the cobalt(II) ion and histidine amino acids. Due to unsuccessful attempts to crystalize Cobalt(II)-Histidine complex in the lab, the quantum mechanics modeling package, G09, was employed to provide the binding mode and interaction between the metal and histidine complex. Geometric parameters were attained in order to predict the crystal structure the complex. Results: The data confirms that complexes between cobalt ions and deprotonated histidine will only settle into a square planar geometry, regardless of the initial geometry. However, with neutral histidine, the complex is not in square planar formation at all. Instead, the five-member ring formed among cobalt and histidine’s N- and C-terminus forms an angle, where N-Co-N is almost linear (167.5°). Conclusion: Different reaction conditions will yield either tetrahedral and square planar geometry at the metal center, which will influence the band gap. Such influence can then be used to create a tunable and broadspectrum solar panel materials
Moisture stress indicators in giant sequoia groves in the southern Sierra Nevada of California, USA
No full textGiant sequoia [Sequoiadendron giganteum (Lindl.) J. Buchholz] trees and their ecosystems are unique natural treasures in the Sierra Nevada, California, where most groves are federally managed for biodiversity, perpetuation of the species, and aesthetic, recreational, ecological, and scientific values. Increasing temperatures during the next several decades may create conditions unfavorable for these giant sequoias. Therefore, it is necessary to develop effective management systems to preserve the health of these giant sequoia groves. This study used a topographic wetness index (TWI) as the indicator of soil moisture conditions to evaluate the vulnerability of giant sequoia groves to soil moisture stress and focused on evaluating TWI distributions among all 70 sequoia groves to assess their vulnerability to soil moisture stress. The TWI values were derived using a 10-m digital elevation model and compared with soil, geology, slope, aspect, and elevation at the sequoia groves to understand the vulnerability of the groves to soil moisture stress. The TWI values were also compared with snow cover persistence derived from 12 yr of MODIS snow cover products. In addition, satellite soil moisture products were used to compare the dry and wet periods predicted by snow cover persistence. Results showed that the groves located at higher elevation are less vulnerable unless the TWI across the groves is low. For the large number of groves with elevations mainly in the 1800- to 2100-m range, the TWI distributions can serve as a first-order indicator of relative vulnerability. Further, this analysis showed that areas with milder slopes and more converging area (higher TWI), plus longer snow cover persistence, should be less susceptible to low summer soil moisture than areas having steeper slopes, more diverging topography (lower TWI), and earlier snowmelt. This analysis can be used to highlight groves that are potentially more vulnerable, particularly when considering TWI, snow cover persistence, and satellite soil moisture together
Color image encryption and decryption using Hill Cipher associated with Arnold transform
Get PDFImage security over open network transmission is a big concern nowadays. This paper proposes another methodology for color image encoding and decoding using two stage Hill Cipher method which is connected with Arnold Transformation. The forgoing created a strategy for encryption and decryption of color image information and touched on just the premise of keys. In this plan, keys and the agreement of Hill Cipher (HC) are basic. Moreover, keys multiplication (pre or post) over an RGB image information framework is inevitable to know to effectively decrypt the first image information. We have given a machine simulation with a standard example and the result is given to support the stalwartness of the plan. This paper gives a detailed comparison between prior proposed methods and this methodology. The system has potential utilization in computerized RGB image transforming and security of image information
On Local Asymptotic Stability of q-Fractional Nonlinear Dynamical Systems
Get PDFIn this paper, locally asymptotic stability of q-fractional order nonlinear dynamical systems is introduced and studied. The sufficient conditions for local stability of such dynamical systems are obtained. Also, useful definitions of fractional order q-integrals and q-derivatives are recalled. Finally, a q-fractional order nonlinear dynamical model is considered
Iterative Solution of Fractional Diffusion Equation Modelling Anomalous Diffusion
Get PDFIn this article, we study the fractional diffusion equation with spatial Riesz fractional derivative. The continuation of the solution of this fractional equation to the solution of the corresponding integer order equation is proved. The series solution is obtained based on properties of Riesz fractional derivative operator and utilizing the optimal homotopy analysis method (OHAM). Numerical simulations are presented to validate the method and to show the effect of changing the fractional derivative parameter on the solution behavior
Soil water content sensor response to organic matter content under laboratory conditions
No full textStudies show that the performance of soil water content monitoring (SWCM) sensors is affected by soil physical and chemical properties. However, the effect of organic matter on SWCM sensor responses remains less understood. Therefore, the objectives of this study are to (i) assess the effect of organic matter on the accuracy and precision of SWCM sensors using a commercially available soil water content monitoring sensor; and (ii) account for the organic matter effect on the sensor’s accuracy. Sand columns with seven rates of oven-dried sawdust (2%, 4%, 6%, 8%, 10%, 12% and 18% v/v, used as an organic matter amendment), thoroughly mixed with quartz sand, and a control without sawdust were prepared by packing quartz sand in two-liter glass containers. Sand was purposely chosen because of the absence of any organic matter or salinity, and also because sand has a relatively low cation exchange capacity that will not interfere with the treatment effect of the current work. Sensor readings (raw counts) were monitored at seven water content levels (0, 0.02, 0.04, 0.08, 0.12, 0.18, 0.24, and 0.30 cm3 cm-3) by uniformly adding the corresponding volumes of deionized water in addition to the oven-dry one. Sensor readings were significantly (p \u3c 0.05) affected by the organic matter level and water content. Sensor readings were strongly correlated with the organic matter level (R2 = 0.92). In addition, the default calibration equation underestimated the water content readings at the lower water content range (\u3c0.05 cm3 cm-3), while it overestimated the water content at the higher water content range (\u3e0.05 cm3 cm-3). A new polynomial calibration equation that uses raw count and organic matter content as covariates improved the accuracy of the sensor (RMSE = 0.01 cm3 cm-3). Overall, findings of this study highlight the need to account for the effect of soil organic matter content to improve the accuracy and precision of the tested sensor under different soils and environmental conditions