In this paper, recommended spiral passive micromixer was designed and simulated. spiral design has the potential to create and strengthen the centrifugal force and the secondary flow. A series of simulations were carried out to evaluate the effects of channel width, channel depth, the gap between loops, and flowrate on the micromixer performance. These features impact the contact area of the two fluids and ultimately lead to an increment in the quality of the mixture. In this study, for the flow rate of 25 μl/min and molecular diffusion coefficient of 1×10-10 m2/s, mixing efficiency of more than 90% is achieved after 30 (approximately one-third of the total channel length). Finally, the optimized design fabricated using proposed 3D printing method.

Application of the network equivalent concept for external system representation for power system transient analysis is well known. However, the challenge to utilize an equivalent network, approximated by a rational function, is to guarantee the passivity of the corresponding model. In this regard, special techniques are required to enforce the passivity of the equivalent model through a post processing approach that minimizes its impact on the original model characteristics. In this paper, the passivity is enforced by expressing the problem in terms of a convex Optimization problem that guarantees the global optimal solution. The convex Optimization problem is efficiently solved by recently developed numerical interior–point methods. This passivity enforcement is also global which indicates that the passivity enforcement in one region does not lead to passivity violation in other regions.

Background and aim: Various scientometric indicators have been developed for quantitative and qualitative evaluation of scientific output. Each of these indicators has its own weaknesses and strengths. The study aimed at using the Keywords as a qualitative evaluation instrument in research of many scholars of Medical Sciences University.Material and methods: This study was conducted as a cross-sectional study within a 6-year period (2005-2010). The research population included all papers published by faculty members of Medical Science University of Babol who were as the first/corresponding authors with at least 2 papers and these indexed articles in periodicals published in WOS during this period. The data were collected by means of a tailor-made data collection sheet. The repeated or synonym Keywords were collected from different papers of an author and were analyzed in terms of repetition for qualitative evaluation of the research of every scholar. The data were analyzed by using descriptive statistical indexes and statistical software spss version16.Findings: During this period, 127 articles have been indexed in WoS database from researchers of this University. in 11 articles of 300 words, 21 repeated words or synonyms were used by 25 researchers who had two or more than two papers. By considering these findings, the overall ratio of articles with repetitive Keywords was 16% and the proportion of repeated Keywords to whole words was 7%.Statistical processing of the data using linear regression indicates an inverse relationship between the number of articles of each author and repeated Keywords or synonyms in his/her articles. So, by increasing the number of articles for every author from 2 to 5, the repeated words in per article were decreased to 0.83, 0.77, 0.25 and finally zero, respectively.Conclusion: low rate of the same Keywords and synonyms in the articles of one researcher may be a sign of dispersion and lack of coordination in research activities. Therefore, regarding the coordination and concentration of the subject in scientific activities is very important in assessing the quality of research and researchers.

Grammatical texts like any other text need to scientific methods for get the concepts and meanings found in text phrases and sentences. Words, phrases and compounds, methods, structures, assumptions and thought of the author as well as basic principles are the key elements of the discovery of meaning in grammatical texts. Al-Kitab is the first consistence book on Arabic syntax, and is by no means an exception to these linguistic and extralinguistic principles. The present research is analytic descriptive using methodological terminology to study a few Keywords of al-Kitab frequently used in the structure of the book. Principles such as synonymy, antonymy, homonymy, the lexical and customary truth are applied to these Keywords. The authors’ attempts were mainly concerned with the comparative discussion of some parts of the book to show the direct impact of words on text and to remind readers about the misunderstanding the Keywords.

An abstract is a self-contained, short, powerful statement that describes a larger body of work. It may be incorporated as part of a published paper, book, grant proposal, thesis, research report, or a conference paper. An abstract of a scientific paper will be published online independently, so it should make sense when it is read alone. An abstract of a hypothesis-testing paper consists of at least four key elements, as follows: (1) study question/hypothesis/aim, (2) experiments/material and methods, (3) results, and (4) response to the question/conclusion(s). The abstract usually begins with a background and may end in applications, recommendations, implications, or speculations. The abstract is one of the many features of a manuscript that competes for the readers’ attention; therefore, it should be informative, accurate, attractive, and concise. Since a huge amount of work must be compressed into a few sentences, writing an abstract may be a difficult task that needs professional skills. Here, we provide a practical guide to writing an abstract and selecting Keywords for a hypothesis-testing medical paper.

Quranic linguistics is one of the new issues in the Quranic sciences, being considered as one of the most important branches among the methods of understanding Quran. Semantics, one of the branches of Linguistics, is concerned with the study of the key words of Quran. By key words, we mean those words which can play an important part in making evident the different meanings of the Quranic verses, if their meaning is studied in a survey. In this article, focusing on polysemy in Semantics, we have pondered over Mulla Sadra's view on this issue and examined his commentary on some of the Quranic verses, as an example. Analyzing Quranic key words in a polysemous method will open new scopes to the scholars of Quranic sciences and commentary and in considered a new method for the subject-concerning interpretation of Quran in order to reveal its miraculous aspects, literally and semantically.

Background and aim: Due to the importance of Keywords in the field of research and scientometrics, the Keywords used in scientific outputs of mathematics education specialists were investigated in this study to determine the scope of their research. Material and methods: This cross-sectional study was conducted on the Persian scientific papers published by mathematics education specialists who were the first author and published at least three papers for a 25-year period from 1993 to 2017. Under these conditions, 48 papers presented by eight mathematics education specialists were identified. Descriptive and inferential statistics were used to process the number and repetition of Keywords. Findings: Out of 204 Keywords, 10 Keywords were applied 44 times repeatedly (or synonymously). The ratio of total articles to duplicate Keywords was 66% and the ratio of duplicate Keywords to total Keywords was 22%. Linear regression test indicated a direct relationship between the number of articles and ratio of duplicate Keywords. Conclusion: The high proportion of duplicate Keywords suggests the subject similarity and focus of articles of mathematics education specialists in Iran.