Volume 17 – Issue 1

In this paper we shall consider the various types of linear and non-linear fuzzy integro-differential equations of second kind like fuzzy Volterra integro-differential equation, fuzzy Fredholm integro-differential equation and mixed fuzzy Volterra-Fredholm integro-differential equation and suggested the algorithm of advanced numerical technique like Laplace homotopy perturbation method to find out their solutions. The application of this method on various types of fuzzy integro-differential equations shows the efficiency and reliability of the proposed method.

The objective of this article is to describe numerical method for the solution of two-point boundary value problems with an internal boundary condition. We present the derivation of the propose Numerov type method. The order of the propose method is four. In numerical section of the article we shall consider some linear and non linear model problem and solve those problems by the propose method to illustrate the efficiency and the accuracy

In this article we study the new proof of very fundamental property of Nagel Point

Let α(s) be an arc on a connected oriented surface S in E^3 , parameterized by arc length s , with curvature k and length l . The total square curvature K of α is defined by l^1_0k^2 ds. The arc α is called a relaxed elastic line if it is an extremal for the variational problem of minimizing the value of K within the family of all arcs of length l on S having the same initial point and initial direction as α . In this study, we show that a geodesic is a relaxed elastic line if and only if it is planar and an asymptotic curve cannot be a relaxed elastic line. Also, we obtain a criterion for a line of curvature to be a relaxed elastic line

The aim of this article is to show how asymptotic series theory can be used to establish bounds for some expressions. For sake of explicitness, we discuss two problems posed by N. Schaumberger and M. S. Klamkin.

Let G be a simple connected graph. We redefined adjacency for any two vertices if there is connected two edges between any two vertices i and j. In this case, this vertices are called 2-adjacency and denoted by i~_2j . In this study, we redefined the energy of Adjacency matrix A(G) and Laplacian matrix L(G) by using 2-adjacency definition. Also, we found some bounds for the energy of A(G) and L(G) of a graph , respectively by using 2- adjacency.

In the present work, the authors aim to present a model analyzing the propagation of the effect of the governmental acquisitions modification in the economy using a “lag” equation. The authors approached several aspects: a) determining the effects of the governmental acquisitions modification on the revenue at balance; b) calculating the dynamic multipliers; c) calculating the static efficiency; d) determining the number of economic cycles needed for the dynamic efficiency to represent a certain percentage of the static efficiency; e) determining the number of economic cycles needed for the governmental acquisitions modification to no longer generate effects in the economy.

In this paper, we apply the binomial transform to the Quadrapell sequence. We investigate some interesting properties the so-obtained new sequence. Moreover we define the matrix sequence of the Quadrapell numbers. Then, we give properties of these new matrix sequences. Finally, we apply binomial transform to Quadrapell matrix sequence and give some algebraic properties of the new sequence.

Any organization makes assessments to achieve improvements in employee activity or in those processes that do not bring the desired performance. If, through various methods used to determine the degree of fulfillment of performance by employees, these performances are met, then the employees should be rewarded financial or nonfinancial, and if they are not fulfilled, employees must be sent to various training programs, learning or development processes in order to improve their performance. In this article we analyze some methods and models to assess performance and we are also present the advantages and disadvantages of their use in organizations. We have also realized a case study in an organization that uses as evaluation method, the Gauss method, showing its importance by using simulation process, and showing its benefits and disadvantages of using such a method of performance evaluation.

The analysis aims to identify the underlying reasons for the redesign of behavioural patterns of the tourists, shifting to new forms of tourism (such as adventure tourism) and creating innovative ways of recreation and personal development through means designed to stimulate creativity and to develop skills. Taking into account the constraints imposed by the global economic crisis, which had a strong negative impact on the tourism in general, and the adventure tourism, in particular, the study offers a multitude of possibilities that could lead to alternative scenarios, which adds new values of this form of tourism, giving thus the opportunity to overcome the obstacles imposed by the current contradictory economic context.

Polyphenolic compounds were determined from an extractive solution of grape seeds (Black Magic variety). Separation of the phenolic compounds was done by an adapted USP30 HPLC method. The following phenolic compounds were founded: ellagic acid, gallic acid, E-resveratrol, chlorogenic acid, felluric acid, vanillin and caffeic acid. The highest amount of phenolic compounds in grape seeds reaches the value of 2312.737 mg ellagic acid/100g dry seeds of Black Magic grape variety

Organic cosmetics represent one of the best approaches in skin care since millions of people rediscover the power of nature by using them. In order to bring awareness on this products free of chemicals, less invasive and rich in bio-active compounds, capable of healing skin disorders such as acne and dermatitis, marketing is the key to pinpoint this information. Good marketing has become increasingly vital for success. The first decade of the 21st century challenged firms to prosper financially and even survive in the face of an unforgiving economic environment [1]. To gain consumers’ attention, people need a better understading of this product category. They need to understand the benefits of plant materials used in the manufacturing process, how the products are or can be naturally preserved, what effects produce on the skin, if they are dermatologically tested and approved by the Health Ministry etc. The aim of this paper was to develop unique marketing and PR tools for one roumanian manufacturer of organic cosmetics to icrease awareness of their unique cosmetic recipes, ingredients used, product and services benefits. During the year of 2016 the company used our tools and the results were impressive

Alkyd resin coatings are applied, mostly, due to their versatility, proper stability, and good compatibility with other modifying agents like curing agents, antioxidants, and nanoparticles that allow manufacturing resins with improved properties. The proportions between mixture components as well as the control of curing process parameters influence the final features of the final product. In this study, three types of alkyd resins consisting of phthalic anhydride, pentaerythritol, benzoic acid, propylene glycol as well as three different type of vegetable oil, were investigated. The content of vegetable oil was the same. In all alkyd formulations, for the curing process, melamine resin was used and the resulted mixture was tested for thermal and radiation stability. Epoxy resin, acrylamide, and SiO2 and Al2O3 nanoparticles were used for the improvement of the material. The structural change of obtained polymers was investigated by IR spectroscopy with attenuated total reflection (ATR) and conclusions about their stability were drawn. The thermal stability of irradiated and non-irradiated samples was investigated by chemiluminescence in stationary air atmosphere, as well.

This work is aimed at investigating the microstructure and mechanical properties of as-cast Al-Cd alloys system were prepared by casting technique. The Al-Cd binary aluminium alloy was analyzed by employing Rockwell hardness HRF, metallograph, XRD, SEM and EDS methods. Evolution of hardness confirmed that the studied alloys are age-hardenable alloys. The as-cast Al-2%Cd alloy is the one who present the mechanical properties (48,75HRF) improved compared to other studied alloy. The results of XRD and optical microscope revealed the presence of the one main phase α-Al of a crystalline structure CFC and there is no new phase formed.

Pyrethrins content was determined for two chrysanthemum species namely: Chrysanthemum cinerariifolium and Chrysanthemum leucantheum. In order to determine the most efficient solvent for pyrethrins extraction three solvents were used: petroleum ether (I), a mixture of petroleum ether, ethanol and acetone (1:1:1) (II) and methanol (III). Spectrophotometric method used for determination of pyrethrins is based on pyrethrins colour reaction with 2,4-dinitrophenylhydrazine followed by measurements of resulting compound at 377 nm wavelength. Pyrethrin content was determined comparing to α-cypermethrin calibration curve. According to the obtained results for the analysed chrysanthemum extracts the most efficient solvent for pyrethrins extraction was methanol and the highest pyrethrins content was found in Chrysanthemum cinerariifolium petals

From the psychological point of view, an important step in human development is the moment when you discover who you are and what you should do with your life. The success in career depends heavily on the goals and the effort you deposit, but also depends on better knowledge about capabilities, needs and personal interests. The psychological interests refer to a person’s preferences for certain things, knowledge areas of activity and have particular relevance for the future careers. At the level of the Romanian society there are a series of changes that create fluctuations in the motivational structure and also in the axiological profile of the individual, and that has influence on the sphere of interest and on the personally vision of career. Considering the area of Science, in Romania, the Physics, Chemistry and Biology teachers have an important role to stimulate the students’ interest in Science, and consequently, they can advise or guide the students towards choosing a scientific career. In this respect, the present paper aims to discover to what extent students are interested in the scientific activities, particularly on the cognitive interests measured in relation to their options for a possible scientific career. The study was performed in the FP7 European project called IRRESISTIBLE which has the major objective to promote the dimensions of Responsible Research and Innovation in educational activities.

In this so-called Age of Knowledge, we should help the students, learners and productive members of the society to be informed on the latest news that appear in various fields. The practical experience proved that giving to the students such examples of how to use the new technologies and advanced materials in their daily life, we can convince them to valorize the importance of Science lessons in their acquisition of knowledge, and to increase their motivation for learning Science [1, 2]. More than that, from the teaching perspective, the Science lesson, through its particular didactics, represents a powerful facilitator for counseling and vocational guidance. In fact, as a first step, counseling the students in the area of Science, could be a feasible demarche for them, in order to promote a future career in scientific areas. Starting from abovementioned aspects, the partnership of the LLP KA3-ICT project no. 511787-LLP-1-2010-1-TR-KA3-KA3MP: “NTSE – Nano-Tech Science Education” designed the NTSE Virtual Laboratory as a main result, containing facilities and educational valences in order to help the teachers in their attempt to provide to young learners the necessary knowledge for helping them to understand the new scientific discoveries and technologies [3]. The Virtual Laboratory resources have been implemented at different students’ level: from lower and upper secondary school to university students [4]. The paper includes the results of the case studies developed in several Romanian school settings, and emphasizes on the use of different facilities of NTSE Virtual Laboratory during the practical activities of students, university students (prospective Science teachers) and PhD students, who developed a variety of skills, some of them critical for their further formation/specialization.

The Hg (A=200) isotope belong to the dynamical symmetry O(6). The (IBM1.FOR) was used to study the energy levels and their transitions, where it was identified spin and parity for some energy levels is not exactly determined experimentally, as it predicted some of the energy levels and their transitions for some bands, it was assured that spin and parity for energy levels number (2) and it was predicted for energy levels number (6), the probability of electric transitions B (E2) values and reduced matrix elements ⟨L_f||T̂^(E_2)||L_i ⟩ for isotope under study was calculated by using the computer code (IBMT), In addition the calculate B(E2) ratio, As it has been found the intrinsic quadrupole moment (Q_0 ), deformation parameter , the potential energy surface (P.E.S), the square of rotational energy ħ^2ω^2 and the moment of inertia 2ʹϑ/ħ^2 to clarify the shape of the nucleus.

Hastelloy C2000 is a superalloy used in the chemical processing, pollution control and waste treatment industries. This alloy contains a nominal amount of 52-60% of Ni, 15-31% of Cr, 9-16% of Mo, and small additions of other elements such as iron, copper, tungsten, etc. Its matrix is austenitic and its structure is face-centered cubic. The objective of our work is to study the structure of the Hastelloy C2000 and this by a heat treatment at four temperatures: 700 °C, 800 °C, 900 °C and 1000 °C with a prolonged maintenance at each temperature during three hours. The monitoring of the structure is performed by using the X-ray diffraction (XRD). The X-ray diffraction spectra obtained after the heat treatments, show the presence of peaks of the precipitates and the peaks of the austenite phase. For the crystallographic parameters of the mesh before and after the four heats treatments, we remark an increase of the parameter a and the volume of the mesh as a function of treatment temperature

Fractional calculus is of vital importance and its significance is increased a lot since last many years. In this article, fractional derivatives in Caputo’s logic is used to construct exact solutions for three-dimensional Kudryashov–Sinelshchikov (KS) equation of fractional order, which describes the convey of nonlinear waves in a bubbly liquid. A comprehensive fractional complex transform is appropriately used to renovate this equation to ordinary differential equation which afterward resulted into number of exact solutions via Exp function method. The efficiency of under study method is checked by computational work and graphical representation. We develop the corresponding solutions containing the periodic, solitary wave solutions for   0 , and kink wave solutions for χ=0 . Effects of χ on the dilation factor, steepness and velocity of the kink wave solutions are discussed. With the increasing magnitude of  , the dilation factor and steepness of the kink wave solutions increase, while the velocity of the kink wave solutions first decreases and then increases

In the present paper, unsteady MHD flow past an impulsively started oscillating vertical plate with constant wall temperature and variable mass diffusion in the presence of Hall current is studied here. The fluid considered is an electrically conducting. The Laplace transform technique has been used to find the solutions for the velocity profile and skin friction. The velocity profile and skin friction have been studied for different parameters like Schmidt number, Hall parameter, magnetic parameter, mass Grashof number, thermal Grashof number, Prandtl number, and time. The effect of parameters is shown graphically and the value of the skin-friction for different parameters has been tabulated.