Analysis Apparatus Research Articles

B-spline wavelet discrete-continual finite element method for the local solution to the two-dimensional problem of the theory of elasticity

Introduction. The distinctive article presents a local semi-analytical solution to the problem of the two-dimensional theory of elasticity. The corresponding structures, featuring the regularity (constancy) of physical and geometric parameters (the modulus of elasticity of the material of the structure, the Poisson’s ratio of the material of the structure, dimensions of the cross section of the structure) along one direction (dimension) are under consideration. This direction is conventionally called the basic direction.
 Materials and methods. The B-spline wavelet discrete-continual finite element method (DCFEM) is used. The initial ope­rational formulation of the problem was constructed using the theory of distribution and the so-called method of extended domain, proposed by Prof. Alexander B. Zolotov.
 Results. Some topical issues of construction of normalized basis functions of a B-spline are considered, the approximation technique for corresponding vector functions and operators within DCFEM is described. Along the basic direction, the problem remains continual and an exact analytical solution can be obtained, while along the non-basic direction the finite element approximation is used in combination with a wavelet analysis apparatus. As a result, we can obtain a discrete-continual formulation of the problem. Thus, we have a multi-point (in particular, a two-point) boundary problem for the first-order system of ordinary differential equations with constant coefficients. A special correct analytical method for the solution of such problems was developed, described and verified in numerous papers written by the authors. In particular, we consider the simplest sample analysis of a deep beam, fixed along the side faces and subjected to the load concentrated in the centre of the structure.
 Conclusions. The solution to the verification problem obtained using the proposed version of the wavelet-based DCFEM was in good agreement with the solution obtained using a conventional finite element method (corresponding solutions were constructed with localization and without localization; these solutions coincide almost completely, while the advantages of the numerical-analytical approach are quite obvious). It is shown that the use of B-splines of various degrees within the wavelet-based DCFEM leads to a significant reduction in the number of unknowns.

Logistics approach to organizing ethno-economic industrial clusters (сase of the Tuva Republic)

One of the main branches of economy in Tuva republic is cattle breeding which has developed historically on the basis of Tuva’s geographical position, climate and environmental conditions and centuries-old experience of Tuvinian population. Ethno-economic custom of Tuvinian people together with the governmental support lay the groundwork for the development of regional industrial clusters such as the DUK project (processing of sheep wool and goat hair) and the KESH project (currying of animal skins). In order to raise marketability and promote industrial development on the whole, it seems reasonable to organize groups of manufacturing clusters in the region, which would unite factories dealing with processing of raw materials supplied by traditional ethnic households. The aim of this work is to define optimal geographical coordinates for manufacturing facilities taking into account the location of raw material suppliers, to the effect of minimizing transportation costs. The authors suggest a mathematic model of optimal economic space layout on the basis of the development of traditional industrial system. Cluster analysis apparatus was used as well as logistic approach to formation of production and distribution network taking into account the existing transport infrastructure. Calculations were made using the example of organization and development of Tuvinian light industry cluster based on traditional for this region branch of economy, sheep breeding

Detection and Delineation of Potential Areas for Tourism Activities in Coastal Zone of Ratnagiri District, Maharashtra (India)

Tourism is a device of economic development in developed, developing, and even in underdeveloped countries. The AHP based MCDA techniques used for detection and delineation of the tourism potential zones in the coastal area of Ratnagiri district in Maharashtra (India). The conventional and satellite data viz. ASTER data has been used for spatial analysis in GIS software. Seacoast, elevation, slope, river, LULC, available amenities, accessibility and connectivity, cultural and historical places, and density of settlements used as the criterions for detection of potential zones for tourism activities. The experts’ opinions, literature survey and fieldwork used as the source of information for the selection of criterions and determination of ranks. The weighted overlay technique used to find the comparative levels of tourism potentials: very high, high, moderate and less potentials for tourism. About 13% of TGA shows comparatively very high tourism potential, 25.80% shows high, 54.62 % shows moderate, and 6.57 % shows less tourism potential. The overall accuracy of the categorized map estimated about 89.60%. The thematic maps viz. amenities and settlement were processed using inverse distance weighted (IWD) interpolation technique. Therefore, some areas from the category, ‘high potential’ merged in the category, ‘moderate potential’ and reduced the producer’s accuracy of the classified map. The sandy beaches, lowland area with a gentle slope, river landscape features, road network, cultural and historical places, ideal size of settlements and number of amenities are attractions of tourists in the region. The technique used in this study can be an effective apparatus for precise analysis of site suitability for tourism activities.

FORMATION OF ANALYTICAL TOOLS FOR RESEARCH OF PREREQUISITES FOR EFFECTIVE MANAGEMENT OF RESOURCE POTENTIAL

Introduction., The organization of the resource management system of an agricultural enterprise is subject to both requirements for ensuring the competitiveness of the adopted resource use regime in market conditions and requirements for ensuring the ecological balance of man-made load on agricultural land in today's economic conditions. That is why, it is necessary to ensure the interdisciplinary nature of the formation of the enterprise's management system. This approach makes it necessary to consider analytical support for management decisions in finding a compromise between the environmental and economic interests of sustainable development of the enterprise. Purpose. Development of a system for assessing the current state of the organization of resource potential management to ensure a scientifically based classification of management approaches of agricultural enterprises to resource use. Methods. Studies were conducted on the basis of the use of abstract and logical, statistical, economic and mathematical methods. The methodological basis in preparing the material made dialectical method of knowledge of social and economic phenomena. Results. In the course of scientific research, it was established that the classification functions of discriminant analysis are an effective basis for scientific substantiation of the system of assessment and differentiation of approaches to managing the resource potential of an agricultural enterprise. The main advantage of the discriminant analysis apparatus in this particular situation is the possibility of statistical and mathematical modelling of the principle of classification of the studied objects by an expert group. The obtained models can be used to identify the effectiveness of resource potential management by business entities to diagnose problems and identify sources of resource use efficiency. The quality of the obtained models depends on the correct choice of a set of indicators for evaluating and taking into account business conditions in the parameters. Discussion. The results of testing the proposed approach using statistical data of the Lugansk region allowed us to identify the main prerequisites for improving the efficiency of resource potential management, the main of which is to ensure a balance of the crop production system through regulating the intensity of resource use. Management of mainly market principles has unbalanced the mechanisms of self-recovery of land resources, which, accordingly, requires replacement agrotechnical measures. This requires appropriate investment resources, and resource potential management projects are treated as promising investments. Keywords: management, resource potential, resource use, discriminant analysis, classification functions.

АНАЛІЗ МЕТОДІВ ОЦІНЮВАННЯ ФІНАНСОВОГО ПОТЕНЦІАЛУ ПІДПРИЄМСТВА

In today's turbulent economy, the basis for sustainable development of the enterprise is the effective use of its financial potential, which can ensure the continuity of the production process, timely fulfillment of financial obligations and dynamic development of the business entity by financing investment activities. Therefore, the problem of the enterprise financial potential estimation is relevant. The purpose of the article is to generalize and systematize the concept of "financial potential", analysis of existing methods of its estimation, the advantages and disadvantages identification, the possibility of application in practice. The object of research is the industrial enterprises financial potential and methods of its estimation. Methods used in the study: methods of scientific knowledge, namely analysis and synthesis, induction, measurement, observation, formalization, logical-analytical techniques, as well as the methodological apparatus of financial analysis and mathematical statistics. The main hypothesis of the study is the assumption that the diagnosis of the enterprises financial potential should be based on methods whose use will allow to correctly and unambiguously interpret their results, avoid bias and other shortcomings that reduce the quality of the enterprises financial potential estimation. Presenting main material. The study found that the enterprise financial potential is one of the most important characteristics of its financial condition, associated with the level of attractiveness to creditors and investors and is characterized by available financial opportunities. The concept of "enterprise financial potential" has systematized. The analysis of existing estimation methods of the industrial enterprise financial potential had carried out. The prerequisites for their practical implementation has identified, namely: taking into account the specifics of the industry, the level of financial potential, taking into account trends and dynamics of economic development. Has proved that the analysis of the enterprise financial potential is a key tool in determining the directions of expansion of industrial production. The originality and practical significance of the study lies in the fact that the results of the methodological basis analysis has classified methods for assessing the industrial enterprises financial capabilities, has identified their main advantages and disadvantages, the possibility of use. Conclusions and prospects for further research: the necessity of formation an individual complex vector of the enterprise financial potential research in the context of global socio-economic challenges in accordance with the methodological tools, the determinants of which should be economic and mathematical methods, has substantiated

Modeling of the intercivilization fault effect on the conflict intensity throughout the world

Using the mathematical apparatus of the multifactor regression analysis, the concept of faults between civilizations is verified, formalized and refined. The ethnocultural civilizational distribution of the countries is specified on the basis of the fuzzy cluster method. The mathematical model of fault lines between civilizations is elaborated, which affords the opportunity to estimate and analyze the quantitative values of these faults. Formally, the developed model offers the way to determine evolutionary regularities, systematize and econometrically verify the defining characteristics of actual civilizational clashes. The results of an analysis and comparison of modeling data of intercivilizational faults in 2008 and 2018 revealed the tendencies of individual civilizations to unite and clash, and the effect of these faults on the global conflict as well. The dependence of global threats on the proliferation of weapons and their individual components is assessed. The conflict effect on the socio-economic indicators of clashing civilizations is determined. The correspondence of the modeling outcomes to the real state of intercivilizational faults is verified by comparison with actual historical data. The results of the study encourage to form a comprehensive vision of the nature of modern clashes, whose emergence is caused by the faults between civilizations, and to determine their formal characteristics and regularities of their course.

The Structural Changing Phases of Ifẹ̀ Festivals and Tradition Towards Economic Boost and Cultural Tourism

Festivals provide information on the origin of beliefs, historical antecedents, socio-cultural and socio-political desires, meant for bonding. The resultant effect of participation in festivals enables the participants to protect and sustain the festivals. However, our research informs that a number of the official festival activities with the tones of its referred sacredness in Ilé-Ifè, which ̣ is the domain of data collection and subject of our analysis, are being restructured in outlook and content to boost the economic survival of the people; and for cultural tourism. Tis essay seeks to interrogate these structural reforms, with the mind of identifying improved areas of the age-long tradition, the philosophy of the festival, and the economic value added. The apparatus of analysis shall premise on cultural semiotics and sociology of literature.

The development of real-time digital PCR technology using an improved data classification method

For digital polymerase chain reaction (PCR), data classification is always a crucial task. The dynamic real-time amplification process information of each partition is always ignored in typical digital PCR analysis, which can easily lead to inaccurate outcomes. In this work, an integrated device that offers real-time chip-based digital PCR analysis was established. In addition, an enhanced process-based classification model (PAM) was built and trained. And then the device and the analytical model were employed in classification tasks for different concentrations of Epstein-Barr Virus (EBV) plasmid quantification assays. The results indicated that the real-time analysis device achieved a linearity of 0.97, the classification method was able to distinguish the false-positive curves, and the recognition error of positive wells was decreased by 64.4% compared with typical static analysis techniques when low concentrations of samples were tested. With these advantages, it is supposed that the real-time digital PCR analysis apparatus and the improved classification method can be employed to enhance the performance of digital PCR technology.

Modes of subjectivation, ethos and the “Pathway of passions”: a theoretical-methodological apparatus for rhetorical analysis

The text argues for the possibility of multimodal argumentative analyses. The main objective of this essay was to speculate on how an orator's modes of subjectivation, discursively materialized by ethos, provide evidence for the persuasion of audiences. In order to do that, we use the “Pathway of passions” theory as a theoretical-methodological analysis apparatus. The object of study was the official campaign video of the current state deputy for the State of São Paulo, Arthur Moledo do Val, published on the YouTube website, in 2018. The results of the work indicate that the analysis of multimodal texts is essential at the present time, since the most varied social practices, such as politics, have been using these materialities to persuade. It is also clear that ethos gains more argumentative relevance within a virtual communicative context. Furthermore, the rhetorical perspective of argumentation, transdisciplinary since its genesis, can provide the necessary means to carry out such an undertaking

Features of derivation of formulas for calculation of nodal reactions and coefficients of matrix of rigidity of a finite element with averaged mechanical and geometrical parameters

Currently, the most widely used finite element method for the calculation of spatial structures, significant progress in the development of which is associated with the work of domestic and foreign scientists. In Ukrainian publications the problems of theoretical substantiation of the finite element method and its connection with other methods are considered, concrete types of finite elements and their application to various problems of mechanics of a continuous environment are studied. Much attention is paid to the choice of the appropriate shape of the finite element, the type and degree of approximating functions, as well as the development of methods for deriving stiffness matrices.
 The study of prismatic bodies with constants along one of the coordinates of mechanical and geometric parameters is most appropriate to carry out on the basis of the semi-analytical method of finite elements. Its essence is a combination of finite element sampling and decomposition of displacements in the characteristic direction by a system of trigonometric coordinate functions.
 The analysis of the literature shows that the issues related to the application of the semi-analytical finite element method to the calculation of thin-walled prismatic bodies in elastic-plastic, and massive even in elastic formulations, have not been properly reflected. In addition, there are no publications in this area devoted to the development of universal prismatic finite elements that allow you to explore massive, thin-walled and combined structures.
 The direction of this study is to create on the basis of the semi-analytical method of finite elements of an effective apparatus for numerical analysis of the stress-strain state of massive and thin-walled arbitrarily loaded properties of the material and solve a number of new practically important problems. Therefore, in this work, based on the moment diagram of finite elements, formulas for calculating nodal reactions and stiffness matrix coefficients of a finite element with averaged mechanical and geometric parameters for the study of massive, thin-walled and combined structures are derived.

Flat Disc-Shaped Sampling Probe and Online Re-extraction Apparatus for Mass Spectrometric Analysis of Skin Metabolites: A Proof of Concept.

Sweat analysis provides an alternative and noninvasive way of clinical diagnostics. However, sampling and transferring sweat-derived samples to analytical instruments is challenging. In this report, we demonstrate a method utilizing a flat disc-shaped sampling probe, and a compatible re-extraction apparatus coupled online with extractive electrospray ionization (EESI) mass spectrometry (MS). The probe enables sampling of metabolites from a skin area of ∼2.2 cm2. The subsequent online re-extraction and analysis by EESI-MS further mitigates matrix effects caused by sweat components, thus eliminating sample preparation steps. The total analysis time is only 6 min. We have optimized the key parameters of the system, including flow rate of the nebulizing gas in ESI, pressure of the nebulizing gas in pneumatic sample nebulizer, flow rate of the solvent in ESI, and composition of extractant. The standard solutions (0.1 mL) were supplemented with 0.04 M sodium chloride to mimic the matrix effect normally observed in sweat samples. The method has been characterized with four chemical standards (positive-ion mode of histidine, leucine, urocanic acid; negative-ion mode of lactic acid). The limits of detection range from 1.09 to 95.9 nmol. We have further demonstrated the suitability of the method for analysis of sweat. An attempt was made to identify some of the recorded signals by product-ion scan and accurate/exact mass matching.

Sub-band detection of small-sized objects during airspace sensing with ultra-short radio pulses

The possibility of ensuring the safety of flights of aircraft, such as helicopters, at low altitudes, where there is a high probability of unauthorized appearance of small-sized objects such as unmanned aerial vehicles, is being considered. The possibility of solving the problem of detecting such objects on the basis of radar soundings in the resonant frequency range of the UHF radio wave range is considered. Sub-band processing of the received signals is proposed, based on the division of the spectral definition area into sub-bands, for adaptation to the frequency response band and noise filtering. The mathematical apparatus of sub-band signal analysis using sub-band matrices has been developed. An optimal solution to the problem of filtering responses in given sub-bands is obtained. A procedure for processing the received signals is given when making decisions about the presence of a response in a given sub-band. Estimates of the probabilities of erroneous decisions are given for a given probability of errors of the first kind.

USING OF THE MATHEMATICAL APPARATUS REGRESSION ANALYSIS TO UNIFY THE CALCULATING METHODOLOGY FOR THE T-64B TANK'S OVERHAUL LIFE

The subject matter of the article is the life cycle of a T-64B tank sample during the period from normal operation in a combat training group to resource consumption and carrying out average and capital repairs. The goal of the study is to develop a model of dependence of inter-repair service life of the T-64B tank sample on the machine operating conditions and, on its basis, a methodology for controlling the parameters of individual assemblies and systems of the tank sample during its life cycle. The tasks to be solved are: to analyze the results of statistical records of tank system failures and damages number and identify the predicates set affect the inter-repair service life of the machine depending on conditions of its tasks for the intended purposes; to create the regression equation for getting the unified analytical dependence of inter-repair service life of the T-64B tank sample in the period from normal operation in training and combat group to service life and overhaul; to investigate specific influence of reliability indices on the machine's service life. General scientific and special methods of scientific knowledge are used. The method of hierarchy analysis, mathematical apparatus of probability theory and multidimensional statistical analysis were used. The following results are obtained. A set of predicates influence the inter-repair service life of the machine depending on conditions of its tasks for the intended purposes fulfillment has been determined. A regression equation has been drawn up to obtain a unified analytical dependence of the overhaul life of a T-64B tank sample during the period from normal operation in a combat training group to the development of a resource and carrying out of intermediate and complete overhauls were drawn up. Engineering solutions have been proposed to implement a methodology for monitoring the parameters of individual units and systems of the tank sample during its life cycle, namely integrated real-time monitoring of oil condition and recording of engine operating hours under various load conditions. Conclusions. The space of features characterizes the conditions of the tank sample tasks for its intended purposes, includes service life, crew training, operation, seasonality of the unit’s performed tasks nature, machine operating time since the last service and range of the vehicle before the next overhaul. The analytical relationship between the individual factors determining the conditions under which the T-64B tank sample performs its tasks for the intended purposes and the machine's service life consumption as a dependent variable can be determined in the form of a regression equation. Differentiated control of the parameters of individual assembly units and systems of the tank sample plays a leading role in ensuring the combat readiness and efficiency of the use of aging samples of weapons, insures personnel against possible accidents and catastrophes, sudden failures.

Effective Management of Crisis Communications

In a view of the fact that in modern realities of post-industrial information society, the share of intangible assets in the companies' value has significantly increased. The monetized value of an organization's reputation is a part of such assets which is mainly determined by external communications had arised an issue of ensuring reputation security that has become especially relevant. One of justifications for need to apply crisis communication management is also changed direction of modern business. The reason for the change in modern concepts of effective business management was the new criteria for the service sector efficiency, which is a consequence of intense competition inherent in this highly profitable field of activity, which increases the importance of reputation issues. In turn, the abstract concept of a company's reputation is formed by specific parameters that are important for target audiences and are expressed in the numerical characteristics of the value of intangible assets. Considering the fact that intangible assets often make up a significant part of the companies' value and determine their financial performance, the issues of managing the value of these assets represent one of the most responsible tasks of modern management. There is a definition of the concepts of crisis, crisis communication and communication management as an integral component of crisis management of an organization is given in the terminology of leading Russian and foreign academics. The paper shows the successful result which is critically dependent on communication management effectiveness. Thus, the subject of the study is crisis communication management; the goal is to build a model for analyzing the effectiveness of managing crisis communications. The achieving method of that is to use a mathematical apparatus similar to the apparatus of multi-discriminant analysis (MDA) of Professor Edward Altman. The scientific novelty consists in the application of numerical methods for analyzing the effectiveness of crisis communications, and the result is in describing a model for analyzing the effectiveness of managing crisis communications. The use of the model for analyzing effectiveness of crisis communication management would provide an organization with the opportunity not to lose the achieved level of capitalization, provided that the reputation/communication component is effectively used in its crisis management.

A micro-vibration apparatus for dynamic mechanical analysis of ultrathin polymer films.

We present the designand validation of an apparatus, which is developed based on micro-vibration in cyclic bulge and contraction, to determine dynamic mechanical properties of ultrathin polymer films. By controlling air pressure acting on a polymer membrane, the apparatus exerts simple harmonic or other type periodic stresses on the film, and the resultant real-time deformation of the freely standing film is recorded by using a high-speed CCD camera. From the image frame sequences and the gas pressure data, the real-time stress and strain of the polymer film are attained. Consequently, the dynamic mechanical properties, including biaxial storage and loss moduli, and loss factor can be determined for polymer films with thickness down to 20nm. This apparatus could also be used to determine other mechanical properties such as fatigue and yield for nanoconfined films of soft matter.

USE OF FACTOR ANALYSIS METHODS IN THE STUDY OF THE STRUCTURAL STATE OF THE WELDED JOINT AFTER LASER WELDING

Formulation of the problem. The use of the mathematical apparatus of factor analysis allows us to investigate the stability of correlations between individual variables. It is the correlations between the variables themselves, as well as between the variables and the selected factors that contain the basic information about the stage of development. The results of factor analysis will be informative if they can be interpreted from the point of view of the physical meaning of both the process under study and the factors that were obtained as a result of the application of factor analysis. Therefore, when identifying factors that will be used for further analysis, one should be guided not only by mathematical methods, but also by the physical meaning of identifying factors. Thus, the use of factor analysis in the study of material science problems (for example, the welding process) is reduced to the search and analysis of the most significant characteristics of the process (factors) among the data array that can be obtained during the process under study. Purpose. Investigation of the relationship between the structural state in the zones of the welded joint after laser welding of specimens from steel 10KhSND using the mathematical apparatus of factor analysis. Conclusion. In this work, the study of the relationship of the distribution of the structural state over the zones of the welded joint was carried out using the mathematical apparatus of factor analysis.

Characterisation of SiPM Photon Emission in the Dark.

In this paper, we report on the photon emission of Silicon Photomultipliers (SiPMs) from avalanche pulses generated in dark conditions, with the main objective of better understanding the associated systematics for next-generation, large area, SiPM-based physics experiments. A new apparatus for spectral and imaging analysis was developed at TRIUMF and used to measure the light emitted by the two SiPMs considered as photo-sensor candidates for the nEXO neutrinoless double-beta decay experiment: one Fondazione Bruno Kessler (FBK) VUV-HD Low Field (LF) Low After Pulse (Low AP) (VUV-HD3) SiPM and one Hamamatsu Photonics K.K. (HPK) VUV4 Multi-Pixel Photon Counter (MPPC). Spectral measurements of their light emissions were taken with varying over-voltage in the wavelength range of 450–1020 nm. For the FBK VUV-HD3, at an over-voltage of V, we measured a secondary photon yield (number of photons () emitted per charge carrier ()) of . The emission spectrum of the FBK VUV-HD3 contains an interference pattern consistent with thin-film interference. Additionally, emission microscopy images (EMMIs) of the FBK VUV-HD3 show a small number of highly localized regions with increased light intensity (hotspots) randomly distributed over the SiPM surface area. For the HPK VUV4 MPPC, at an over-voltage of V, we measured a secondary photon yield of . In contrast to the FBK VUV-HD3, the emission spectra of the HPK VUV4 did not show an interference pattern—likely due to a thinner surface coating. The EMMIs of the HPK VUV4 also revealed a larger number of hotspots compared to the FBK VUV-HD3, especially in one of the corners of the device. The photon yield reported in this paper may be limited if compared with the one reported in previous studies due to the measurement wavelength range, which is only up to 1020 nm.

On the creation of databases to assess the impact of chemicals on the organoleptic and general sanitary limiting signs of the harmfulness in the water of water bodies

Introduction. Information on the MPC (TAC) value and the limiting hazard sign is important for the analysis of the hazard of chemicals in the water of water bodies for the health of the population, serves as the basis for the development of preventive measures to ensure safe conditions for water use by the population. For the purpose of specifying the possible adverse effects of the influence of chemicals on the hygienic conditions of water use of the population, information is needed on the entire spectrum of the effects of chemicals on water quality indicators. Materials and methods. The object of the study was indicators characterizing the effect of chemicals on the organoleptic properties of water and the general sanitary regime of water bodies, algorithms for analyzing primary data to determine threshold concentrations for the effect on odor, color, turbidity, foaming, pH, general sanitary regime of water bodies - biochemical oxygen consumption, concentration of nitrogenous connections. To organize the databases, the standard apparatus of the Excel subBD electronic tables was used. The mathematical apparatus of data analysis, grouping and selection of critical indicators of limiting signs is presented. Conclusion. It is concluded that the use of databases allows to study the relationship “concentration - effect”, increases the reliability and accuracy of substantiating the threshold concentration of pollutants in water by the influence of limiting signs of harmfulness.

Health-care preventive measures, logistics challenges and corporate social responsibility during the COVID-19 pandemic: break the ice

PurposeThe study aims to analyze the role of coronavirus testing capacity to possibly reduce the case fatality ratio (CFR) in a large cross-section of countries. The study controlled health-care expenditures, logistics performance index (LPI), carbon damages, and corporate social responsibility (CSR) to understand the nature of causation between the CFR and stated factors.Design/methodology/approachThe study used a cross-sectional regression apparatus for coefficient estimates and variance decomposition analysis (VDA) for forecasting relationships between the variables over time.FindingsThe results confirmed the W-shaped relationship between CFR and case-to-test ratio (CTR) in the presence of a LPI that exacerbates the CFR cases across countries. The VDA estimates suggest that carbon damages, logistics activities, and CSR are likely to influence CFR over time.Originality/valueTo the best of the authors’ knowledge, the study is believed to be the first study that assesses the W-shaped relationship between the CFR and CTR in the presence of dynamic variables, which helps to formulate long-term sustainable health-care policies worldwide.

Comparative between different Natural Sources of Activated Carbon for the Removal Reactive Green Dye from Aqueous Solution

Water pollution is one of the biggest problems facing us, so it requires the need to develop a very high-efficiency and inexpensive absorbent material from natural surfaces and compare it with expensive commercial sorbents. Where in this study an absorbent substance was prepared from the natural surfaces of Syzgium Aromaticum Flower Bud (SAFB), Nigella Sativa (NS) Converted to activated carbon to activated carbon Activated (SAFB), and Activated (NS), as these surfaces are characterized by high porosity, cheap price and very high efficiency in removing dye. The composite was illustrated via different analysis apparatus included FTIR, and FE-SEM, The adsorption result were fitted with Freundlich isotherms. The experimental kinetic result at different primary reactive green dye concentrations, were also analyzed through first model, second model and Elovich model. The obtained data appear that the model pseudo-first model fits the adsorption kinetic result through R2 0.96028, R2 0.9486, R2 0.9016 and R2 0.9620 of SAFB and ACTIVE-SAFB and Nigella Sativa (NS) and Activated (NS) in the same order.