Suitable Computer Research Articles

State-Space Control Systems: The MATLAB®/Simulink® Approach

Abstract These days, nearly all the engineering problem are solved with the aid of suitable computer packages. This book shows how MATLAB/Simulink could be used to solve state-space control problem...

Perturbed Collocation Method For Solving Singular Multi-order Fractional Differential Equations of Lane-Emden Type

In this work, a general class of multi-order fractional differential equations of Lane-Emden type is considered. Here, an assumed approximate solution is substituted into a slightly perturbed form of the general class and the resulting equation is collocated at equally spaced interior points to give a system of linear algebraic equations which are then solved by suitable computer software; Maple 18.

The Valued Life Activities Scale (VLAs): linguistic validation, cultural adaptation and psychometric testing in people with rheumatic and musculoskeletal diseases in the UK

BackgroundThe Valued Life Activities Scale (VLAs) measures difficulty in daily activities and social participation. With various versions involving a different number of items, we have linguistically and culturally adopted the full VLAs (33-items) and psychometrically tested it in adults with rheumatic and musculoskeletal diseases in the United Kingdom.MethodsParticipants with Rheumatoid Arthritis, Ankylosing Spondylitis, Chronic Pain/ Fibromyalgia, Chronic Hand/ Upper Limb Conditions, Osteoarthritis, Systemic Lupus, Systemic Sclerosis and Primary Sjogren’s Syndrome were recruited from out-patient clinics in National Health Service Hospitals, General Practice and patient organisations in the UK. Phase1 involved linguistic and cultural adaptation: forward translation to British English; synthesis; expert panel review and cognitive debriefing interviews. In Phase2 participants completed postal questionnaires to assess internal construct validity using (i) Confirmatory Factor Analysis (CFA) (ii) Mokken scaling and (iii) Rasch model.ResultsResponders (n = 1544) had mean age of 59 years (SD13.3) and 77.2% women. A CFA failed to support a total score from the 33-items (Chi Square 3552:df 464: p < 0.0001). Mokken scaling indicated a strong non-parametric association between items. Fit to the Rasch model indicated that the VLAs was characterised by multidimensionality and item misfit, which may have been influenced by clusters of residual item correlations. An item banking approach resolved a 25-item calibrated set whose application could accommodate the ‘does not apply to me’ response option.ConclusionsThe UK version of the VLAs failed to satisfy classical and modern psychometric standards for complete item sets. However, as the scale is not usually applied in complete format, an item bank approach calibrated 25 items with fit to the Rasch model. Suitable Computer Adaptive Testing (CAT) software could implement the item set, giving patients the choice of whether an item applies to them, or not.

A novel dynamic simulation model for the thermo-economic analysis and optimisation of district heating systems

This paper presents a novel dynamic simulation tool able to assess and optimize the energy, environmental and economic performance of standard and innovative district heating/cooling systems. To this aim, several design and operating parameters (e.g.: weather conditions, heat selling price for users, national unitary price of electricity, etc.) are dynamically taken into account. The heating and cooling demands and loads of the buildings to be fed by the network working fluid are dynamically calculated. The system pipeline network is modelled through a suitable plug-flow approach. Fluid temperatures are calculated in each network node. The optimization of several system design and operating parameters is achieved for different objective functions. A suitable analysis is considered for selecting the most convenient urban zones for system application. The whole simulation model is implemented in a suitable computer code written in MatLab. By such tool useful design criteria and feasibility analyses can be obtained. To show the capabilities of the presented simulation tool, a novel case study, referred to a district heating system supplied by an existing thermoelectric power plant, was developed. The conducted analysis is based on system optimizations focused on the number of users, the selling heat/electricity prices and system geometric features. As for example, for minimizing the system payback to about 14.0 year, the optimal number of users and network length are 5 × 103 and 2.7 km, respectively. In this case the primary energy savings and the avoided carbon dioxide emissions are about 11.0 GWh/y and 16.1 ktCO2/y, respectively.

Application of Solar Organic Rankine System for Energy Generation in Buildings: the Case of Athens

This paper describes the performance of an ORC system driven by solar energy and R134a as working fluid. The system is predicted along the twelve months of the year. The operation of the system and the related thermodynamics are simulated by suitable computer codes and the required local climate data are determined by statistical processing over a considerable number of years. It’s found that the solar to electricity efficiency of this SORC system varies from 0.049 to 0.058 while the ambient temperature varies from 11.3oC to 29.2oC and the total solar irradiance varies from 443 W/m2 to 679 W/m2. The system’s arrangement comprises a solar thermal array which is coupled with an organic Rankine engine. The mean annual overall efficiency of the SORC system is estimated at 0.055 while the thermodynamic efficiency of Rankine is calculated at 0.107. The obvious advantage of this arrangement is that electricity can be produced in buildings by using the existing common solar thermals installed. Easy–to–find machinery is employed in order to attain a simple and practical small–scale organic Rankine cycle arrangement coupled with common solar thermals used widely in Greek buildings for DHW production and space heating assistance.

Exploration of Equivalent Design Approaches for Tanks Transporting Flammable Liquids

Tank vehicles are widely used for the road transportation of dangerous goods and especially flammable liquid fuels. Existing gross weight limitations, in such transportations, render the self-weight of the tank structure a crucial parameter of the design. For the design and the construction of metallic tank vehicles carrying dangerous goods, the European Standard EN13094:2015 is applied. This Standard poses a minimum thickness for the shell thickness for the tank construction according to the mechanical properties of the construction material. In the present paper, primarily, the proposed design was investigated and a weight minimization of such a tank vehicle with respect to its structural integrity was performed. As test case, a tank vehicle with a box-shaped cross-section and low gross weight was considered. For the evaluation of the structural integrity of the tank construction, the mechanical analysis software ANSYS ® 2019R1 was used. The boundary values and the suitable computation for structural integrity were applied, as they are defined in the corresponding Standards. The thickness of the construction material was decreased to a minimum, lower than that posed by the standards, indicating that the limit posed by them was by no means boundary in terms of structural integrity.

Aeromagnetic modelling of Precambrian subsurface structures of the Tasiast area, NW Mauritania

Abstract The NW sector of Mauritania represents the Archaean province of the Reguibat Shield. It is mainly composed of the typical Archaean cratonic association of granitoid gneisses, greenstone belts and granites. The greenstone belts contain high mineral potential, mainly gold. This is particularly the case of the Chami Greenstone Belt, which hosts the large Tasiast gold mine. The gold deposits are hosted along a NS oriented shear zone with a surface of 70 × 15 km 2 . In this study, a subsurface structural model is proposed based on the application of suitable computations on a high-resolution reduced-to-the-pole aeromagnetic anomaly map of the northern Chami area. Upward continuations, apparent magnetic susceptibility, directional derivatives, analytical signal, 3D Euler deconvolution and spectral analyses were performed to build this model. They were used to decipher the main evidenced structural features with the main NNE–SSW, NW–SE and ∼120° N directions, identified on most all computed maps combined with in situ measurements. They probably correspond to mafic dykes, faults and shears rooted up to 5 km in depth, particularly to the north, SW and NE, and southwards and westwards by spectral analyses and 3D Euler deconvolution, respectively. The basement is deeper towards the west and south and crops out towards the NE in agreement with the geological observations. In addition, the high values of magnetic susceptibility ( χ m ) measured in situ on banded iron formations (25.7–35 × 10 −3 SI) SW of Akjoujt could be the origin of metallotect sources associated with magnetic minerals for exploration of gold-bearing and base metals.

Effects of Fuzziness on an MHD Fluid Flow over an Exponentially Accelerated Inclined Plate

In most of the time, the real life phenomena are uncertain. Due to the uncertain nature, consideration of some exact values or definite conditions may cause errors in the solution process. The fluid flow problems are also uncertain due to the presence of various imprecise parameters, variables and conditions. Here, an MHD fluid flow over an exponentially accelerated inclined plate is considered in fuzzy environment. Fuzzy set theory (FST) may help to overcome the uncertain nature of the fluid flow problems. The governing equations and the boundary conditions of the considered problem are fuzzified using the extension principle. The fuzzified governing equations along with the fuzzified boundary conditions are solved using the finite difference method (FDM) by developing suitable computer programming code in Python. The values of the different parameters and variables (initial values) are taken as triangular fuzzy number (TFN). −cut technique is used to find the results. The effects of the various involved parameters and on the velocity, temperature and concentration profile are presented graphically and discussed.

On the interaction between turbulence and ethanol spray combustion using a dynamic wrinkling model coupled with tabulated chemistry

Investigations of the turbulence-flame interaction are conducted for ethanol spray combustion with dynamic flame surface wrinkling (DFSW) models in the context of the Artificially Thickened Flame (ATF) approach. DFSW modeling strategies derived for single-phase flows are extended to improve the characterization of the mixture stratification encountered in dilute spray flames. The two-phase flow is described following an Eulerian–Lagrangian approach within the Large Eddy Simulation (LES) framework under consideration of two-way coupling between both gaseous and liquid phases. In particular, combustion reactions are captured by means of the Flamelet Generated Manifold (FGM) method. An evaporation model accounting for the inter-phase non-equilibrium is applied to address droplet’s heat and mass transfer. Main aspects of the suggested DFSW modeling strategy are systematically analyzed. The obtained results demonstrate fair improvements not only in the estimation of the flame structure, but also in the prediction of the spray properties in comparison to a reference model and the available experimental data. This outcome reveals the strong link between turbulence, flame and dispersed phase, as well as the necessity of a suitable computation of each one of these phenomena.

Two-Stage Method Applied for Approximate Calculations of Selected Types of Statically Indeterminate Trusses

The paper presents examples of approximate calculations of force values in members of selected types of trusses, which are at the same time an internal and external statically indeterminate systems. The two-stage method makes possible the approximate calculation of such trusses by help of, for example, the Cremona’s method. In each stage, a statically determinate truss is considered, pattern of which is defined by removing from the basic truss a suitable number of members. There are also presented results of calculations of the same trusses done by means of suitable computer software together with analyses and comparison of outcomes.

Comparative analysis of weighted arithmetic and CCME Water Quality Index estimation methods, accuracy and representation

This paper aims to investigate and evaluate the difference in the computed WQI using the weighted arithmetic method (WAM) and Canadian Council of Ministers of the Environment (CCME) and the reasons of the exaggeration and permissive of these WQIs. In addition, it also aims to specify the suitable WQI computation method in Iraq. Al-Shula City, Baghdad, Iraq was considered as the case study. The results of estimating the WQI in the Al-Shula City using WA and (CCME) methods for each month fluctuated between 0.103 to 8645 and 8.53 to 58.56, respectively. Hence the WQ fluctuated between excellent to unsuitable for drinking (excellent to poor). However, the range of the computed accumulated WA and CCME WQI was between 8 to 3886 and 9 to 59. Consequently, for the two methods, the class of WQ is fluctuated between excellent to unsuitable and excellent to poor. In addition, the calculated CCME WQIs were always lower than the computed WA WQIs. Therefore, the CCME method is permissive or somewhat lenient in contrast to the WA method. Consequently, the WA WQI is more sensitive to presence of toxic contaminants than the CCME WQI. Therefore, the WA WQI is more suitable to use in Iraq because of the high fluctuation in the level and types of pollution sources.

K X-ray fluorescence parameters of some fourth period elements in a magnetic field

The K X-ray fluorescence (XRF) parameters, which are fluorescence cross-section, vacancy transfer probabilities and fluorescence yield, of some fourth-period elements were investigated in an external magnetic field (8000 Gauss). In order to determine the fluorescence parameters, the samples were irritated with 59.54 keV gamma rays from a 241-Americium radioactive source and the rays emitted from the samples were counted in a system consisting of a silicon – lithium drifted detector, multichannel analyzer, magnetic field implementer, and a suitable computer program. The results were studied theoretically and experimentally using the data that were obtained. It was determined that the experimental results were compatible with the theoretical results for measurements without a magnetic field and K XRF parameters changed with the magnetic field.

Experimental and Numerical Seismic Evaluation of RC Walls Under Axial Compression

Recent studies show that code-based equations usually do not provide an accurate estimate for the shear strength of short reinforced concrete (RC) walls due to the negligence of many important factors including the beneficial effect of axial compression. In the current study, quasi-static reversed cyclic testing is conducted for two RC wall specimens, one under axial load and one without axial load to assess the effect of the axial compression on the shear strength of RC walls in high-rise buildings. The results of the experimental study show that the axial compression load significantly improves the shear strength of RC walls. Results are also compared with the performance-based seismic evaluation code practices. Based on the experimental findings, recommendations are made for improvements in the existing codes. The experimental results are further compared with different numerical models to explore the suitable computer modeling options for non-linear response prediction of RC walls.

Retrieving Land Surface Temperature from Satellite Imagery with a Novel Combined Strategy

Land surface temperature (LST) is a key parameter for land cover analysis and for many fields of study, for example, in agriculture, due to its relationship with the state of the crop in the evaluation of natural phenomena such as volcanic eruptions and geothermal areas, in desertification studies, or in the estimation of several variables of environmental interest such as evapotranspiration. The computation of LST from satellite imagery is possible due to the advances in thermal infrared technology and its implementation in artificial satellites. For example, Landsat 8 incorporates Operational Land Imager(OLI) and Thermal InfraRed Sensor(TIRS)sensors the images from which, in combination with data from other satellite platforms (such as Terra and Aqua) provide all the information needed for the computation of LST. Different methodologies have been developed for the computation of LST from satellite images, such as single-channel and split-window methodologies. In this paper, two existing single-channel methodologies are evaluated through their application to images from Landsat 8, with the aim at determining the optimal atmospheric conditions for their application, instead of searching for the best methodology for all cases. This evaluation results in the development of a new adaptive strategy for the computation of LST consisting of a conditional process that uses the environmental conditions to determine the most suitable computation method.

Lattice constant prediction of A2XY6 cubic crystals (A = K, Cs, Rb, TI; X = tetravalent cation; Y = F, Cl, Br, I) using computational intelligence approach

Lattice constant mismatch between materials affects the quality of thin film fabrication. For this reason, lattice constants information is vital in the design of materials for technological applications. The determination of lattice constants via experimental analysis is relatively expensive and laborious. As a result, several linear empirical models have been proposed to predict the lattice constant of crystal structures. However, the accuracies of these models are limited partly due to their failure to account for nonlinearity in the atomic parameters-lattice constant relationship. Machine learning techniques have shown excellent ability to deal with nonlinear problems in many areas of materials science; hence, they are considered suitable computation tools to study the crystal structure of materials. In this contribution, we developed a support vector regression (SVR) model to predict the lattice constant of cubic crystals of the form A2XY6 (A = K, Cs, Rb, TI; X = tetravalent cation; and Y = F, Cl, Br, I). The SVR algorithm uses the ionic radii and electronegativities data of the constituent elements of A2XY6 cubic crystals as model inputs. The robustness of the proposed model was demonstrated by comparing our result with an existing linear model based on 26 cubic crystal samples. The result revealed a total relative deviation of 1.757 and 2.704 for the SVR model and the existing linear equation, respectively. This result proves that the SVR model has a huge potential in the search for new materials for different applications.

Analysis of Suitable Natural Feature Computer Vision Algorithms for Augmented Reality Services

Analysis of Suitable Natural Feature Computer Vision Algorithms for Augmented Reality Services

MFSPV: A Multi-Factor Secured and Lightweight Privacy-Preserving Authentication Scheme for VANETs

Vehicles authentication, the integrity of messages exchanged, and privacy-preserving are essential features in vehicular ad hoc network (VANETs) security. Most of the previously proposed VANETs security solutions do not sufficiently satisfy the security and efficiency requirements. Besides, most of those solutions are heavily dependent on the system key and long-term sensitive data stored in an ideal tamper-proof device, which may not be practical or ideal for resource-constrained onboard units (OBUs), especially in the case of an unexpected cloning or physical attack. Therefore, a robust authentication solution should consider those security issues and the nature of resource-constrained nodes. To satisfy all these requirements, we propose a lightweight multi-factor authentication and privacy-preserving security solution for VANETs. It employs a combination of physically unclonable functions (PUF) and one-time dynamic pseudo-identities as authentication factors. Furthermore, it eliminates the heavy dependency on the system key by decentralising the wide precinct of the certificate authority (CA) into regional domains and achieves robust control of domains keys. A detailed analysis demonstrates that our scheme efficiently meets the VANETs security requirements, and offers more suitable communication and computation costs and features than existing schemes.

Systematic Development of Drug Nanocargos Using Formulation by Design (FbD): An Updated Overview.

Nanostructured drug delivery formulations have lately gained enormous attention, contributing to their systematic development. Issuance of quality by design (QbD) guidelines by ICH, FDA, and other federal agencies, in this regard, has notably influenced the overall development of drug products, enabling holistic product and process understanding. Owing to the applicability of QbD paradigms, a science lately christened as formulation by design (FbD) has been dedicated exclusively to QbD-enabled drug product development. Consisting of the principal elements of design of experiments (DoE), quality risk management (QRM), and QbD-enabled product comprehension as the fundamental tools in the implementation of FbD, a variety of drug nanocargos have been successfully developed with FbD paradigms and reported in the literature. FbD aims to produce novel and advanced systems utilizing nominal resources of development time, work effort, and money. A systematic FbD approach envisions the entire developmental path through pivotal milestones of risk assessment, factor screening and optimization (both using appropriate experimental designs), multivariate statistical and optimum search tools, along with response surface modeling, usually employing suitable computer software. The design space is one of the fundamental elements of FbD providing the most sought-after regulatory flexibility to pharma companies, postapproval. The present paper provides a bird's eye view of the fundamental aspects of FbD terminology, methodology, and applications in the development of a wide range of nanocargos, as well as a discussion of trends from both technological and regulatory perspectives.

Bayesian Nonparametric Monotone Regression of Dynamic Latent Traits in Item Response Theory Models

Parametric methods, such as autoregressive models or latent growth modeling, are usually inflexible to model the dependence and nonlinear effects among the changes of latent traits whenever the time gap is irregular and the recorded time points are individually varying. Often in practice, the growth trend of latent traits is subject to certain monotone and smooth conditions. To incorporate such conditions and to alleviate the strong parametric assumption on regressing latent trajectories, a flexible nonparametric prior has been introduced to model the dynamic changes of latent traits for item response theory models over the study period. Suitable Bayesian computation schemes are developed for such analysis of the longitudinal and dichotomous item responses. Simulation studies and a real data example from educational testing have been used to illustrate our proposed methods.

LabVIEW Based Determination of Oxygen Saturation from ECG Signals

This research paper demonstrates the measurement of oxygen saturation (SAO2) from the ECG signal using LabVIEW 11.0 .SAO2 is the percentage of hemoglobin molecules that contain oxygen. The optimum level of SAO2 in a human being should be 92%.When it goes below 90% it causes hypoxemia (anemia). When SAO2 reduces below 65%, it will cause damage in the functioning of mental activity .When it reduces below 55% it causes unconsciousness. Hence sustaining the optimum value of SAO2 is crucial. Hence maintaining optimum level of SAO2 is important. The latest technology which utilizes pulse oximeter has its own drawbacks. To overcome these disadvantages, a new methodology by which SAO2 can be measured from ECG signals is proposed. The ECG signal from the patient is acquired by NI USB 6211 DAQ module. By determining the pulse numbers from the ECG waveform, the SAO2 level can be determined by suitable mathematical computations. Diagnostics and implementing control action can be done with the support of LabVIEW software.