61 research outputs found
On Investigation an Assessment of Social Life of Dehdasht City Quarters using ELECTRE Model
Capabilities and facilities in urban areas have developed through the past of several years The appearance of these capabilities and facilities has come out through the cost of financial human and environmental Mere attention to physical skeletal and population and ignorance social factors in many of the previous studies has caused the failure of them The purpose of the present study is assessment of the social capacity of Dehdasht city quarters The method of the study is analytical-scale and has been conducted according to documentary and library research The data and information include related features and criteria according to assessment of the capability and capacity of social life in Dehdasht city quarters like identity and place belonging cooperation security dynamicity and vitality variety and social diversity and increasing the density through the model of ELECTRE According to the purpose of the research winch is the assessment and selection of the best quarter four quarters were chosen from different parts of the city The results showed that the old quarters were superior than the other ones and this fact refers to vitality and dynamicity of life as the results of relationship among different neighbors and place belonging residents cooperation in the quarter affairs and social variety in the construction of the old quarters The other places were given to the approximate new middle and new quarters which results from the lack of identity and lack of belonging in relation to the other quarter
Grammar Consciousness-Raising Activities and Iranian EFL Learners' Attitudes Toward English Language
The first purpose of this study was to investigate the effect of consciousness-raising (C-R) activities on learning grammatical structures by Iranian EFL learners. The second one was to investigate the effect of gender through C-R activities and tasks. Finally, this study wanted to investigate the Iranian students' attitudes toward learning English prior to and after applying the C-R activities. An attitude questionnaire was use to investigate the participants' attitudes toward learning English before and after applying C-R activities. Data analysis indicated that using C-R activities in is significantly more effective than the traditional approaches. Regarding gender, male outperformed females. Therefore, it is recommended that other teachers consider C-R activities as useful options in teaching other aspects of language. Based on the statistics and findings, Iranian students' attitudes toward learning English language were not much different prior to and after applying C-R activities
On the Relationship between Iranian EFL Learners' Multiple Intelligences and Their Learning Styles
The current work reports investigation of the relationship between Iranian EFL learners' multiple intelligence (MI) profiles and their learning styles (LSs). The study also attempts to find out the most and the least dominant learning styles among the participants. The study further examines whether there is any significant difference between genders in using the different types of learning styles. To this end, two questionnaires, a 90-item multiple intelligences questionnaire and a 24-item learning styles questionnaire adapted from Willing (1988), were distributed among 120 Iranian EFL learners (60 males and 60 females) during their class time at the universities of Sistan and Baluchestan, Iranshahr, and Yasuj. In order to find answer to the first research question, the Pearson Correlation analysis showed that there is a significant positive relationship between the different types of multiple intelligences and learning styles in particular and the multiple intelligences and learning styles as general factors. Descriptive statistics was also run and considered communicative type of learning styles as the most dominant type and Authority-oriented learning style as the least dominant learning style type. Finally, the results of an independent-samples t-test analysis revealed that there is only a significant difference between male and female students in using communicative type of learning styles. That is, female students use this type of learning style more than male ones. The data analyses further indicated that there is no significant difference between genders in employing learning styles as a general factor
Postmethod Pedagogy and Iranian EFL Teachers’ Understandings: Is a Promising Trend on the Way?
The profession of second language teaching has experienced fundamental fluctuations in both theory and practice. With its own proponents and opponents, the postmethod was considered as the practical and reasonable solution to the limitations of the confining concept of the method. The purpose of this qualitative study was to elicit nonnative EFL teachers’ viewpoints and perceptions regarding postmethod pedagogy. In fact, the researchers were interested to know about nonnative EFL teachers’ perceptions of postmethod condition regarding their own context and needs. Selected based on purposive sampling procedure, the participants of this study were 10 nonnative EFL teachers categorized into three groups based on their teaching experience. The participants took part in semi-structured interviews and they were asked a series of questions to elicit their perceptions and interpretations of postmethod. The results of the study revealed some rays of hope in some cases, though not promising in a full manner. In other words, although nonnative EFL teachers could not mention the postmethod principles explicitly, they showed a logical understanding of postmethod pedagogy tenets and its applications in their teaching practices and procedures. The results of this study can help teacher educators design more effective teacher education courses and in-service programs to enhance nonnative EFL teachers’ viewpoints and perceptions regarding postmethod pedagogy and its implications in language teaching and learning processes
Temperature-Dependent THz Properties and Emission of Organic Crystal BNA
As high-average power ultrafast lasers become increasingly available for
nonlinear conversion, the temperature dependence of the material properties of
nonlinear crystals becomes increasingly relevant. Here, we present
temperature-dependent THz complex refractive index measurements of the organic
crystal BNA over a wide range of temperatures from 300 K down to 80 K for THz
frequencies up to 4 THz for the first time. Our measurements show that whereas
the temperature-dependent refractive index has only minor deviation from room
temperature values, the temperature-dependent absorption coefficient decreases
at low temperature. We additionally compare these measurements with conversion
efficiency and spectra observed during THz generation experiments in the same
temperature range and using the same crystal, using an ultrafast Yb-laser for
excitation. Surprisingly, the damage threshold of the material does not improve
significantly upon cooling, pointing to a nonlinear absorption mechanism being
responsible for damage. However, we observe a significant increase in THz yield
at lower temperatures, which is most likely due to the reduced THz absorption.
These findings will be useful for future designs of high average power pumped
organic-crystal based THz-TDS systems
Broadband THz-TDS with 5.6 mW average power at 540 kHz using organic crystal BNA
We demonstrate efficient optical rectification in the organic crystal BNA
(N-benzyl-2-methyl-4-nitroaniline), driven by a temporally compressed,
commercially available industrial Yb-laser system operating at 540 kHz
repetition rate. Our THz source reaches 5.6 mW of THz average power driven by
4.7 W, 45 fs pulses and the resulting THz-TDS combines a very broad bandwidth
of 7.5 THz and a high dynamic range of 75 dB (in a measurement time of 70 s).
The conversion efficiency at maximum THz power is 0.12%. To the best of our
knowledge, this is the highest THz power so far demonstrated with BNA, achieved
at a high repetition rate, and enabling to demonstrate a unique combination of
bandwidth and dynamic range for THz-spectroscopy applications.Comment: 5 pages, 5 figures. Submitted to APL Photonic
High-power intracavity few-cycle THz pulse generation using thin lithium niobate
Resonant enhancement both in passive and active resonators is a well-known
technique for boosting the efficiency of nonlinear frequency conversion at high
repetition rates. However, this route has remained poorly explored for the
generation of few-cycle broadband THz transients due to the inadequacy of
typically employed nonlinear crystals. Here, we demonstrate that thin lithium
niobate crystals are a promising platform to circumvent current difficulties.
Using a 50-um thin lithium niobate plate intracavity of a compact high-power
mode-locked thin-disk laser, we generate broadband THz pulses with a spectrum
extending up to 3 THz at 44.8 MHz repetition rate, driven by 264 W of
intracavity average power. This approach opens the door to efficient high-power
single-cycle THz generation at high repetition rates, scalable to
kilowatt-level driving power with low cost and complexity
A social work study on measuring the effects of social cognitive consultation on welfare receivers' entrepreneurship attitudes and behavior
One of the most important responsibilities of welfare receivers in all communities is to find a job. In many cases, people are encouraged to act as entrepreneurs and create jobs and opportunities. In this study, we perform an empirical study among 280 welfare receivers to measure the effects of social cognitive consultation on changing receivers' entrepreneurship attitudes. The study uses Bandura's social cognitive questionnaire and select 30 volunteers who receive the lowest marks in this survey and they are divided into two groups. The study provides a consultation among them for eight consecutive sessions of two hour-period and the results indicate that the consultation can change both welfare receivers' perception and their attitude, significantly
Towards Intense Ultra-Broadband High Repetition Rate Terahertz Sources Based on Organic Crystals [Invited]
Increasing the average power of broadband, few-cycle terahertz (THz) sources
is currently a topic of intense investigation, fueled by recent immense
progress in high average power femtosecond laser driving sources at 1030 nm.
However, many crucial applications would benefit not only from an increase in
average power, but also from ultra-broad bandwidth, while maintaining high
dynamic range at these frequencies. This calls for the challenging combination
of high repetition rates and high average power simultaneously. Here, we
discuss the recent progress in the promising approach enabled by organic
crystals for THz-generation. Specifically, this review article discusses
advances with the most commonly used organic crystals BNA, DAST, DSTMS, OH1 and
HMQ-TMS. We place special emphasis on nonlinear and thermal properties and
discuss future directions for this field
Bibliometric Analysis and Topic Modeling of Information Systems in Maternal Health Publications
Due to the importance of maternal health for the development of society and the role of information systems in improving healthcare, this study aims to investigate and analyze the characteristics and topics of articles published in the field of information systems in maternal health. The articles were retrieved from the Web of Science (WoS) on October 23, 2021. The bibliometric indicators included the number of documents and citations, top journals, institutes, and countries. The co-authorship collaboration network of the countries was examined using Bibliometrix 3.1 package and VOSviewer software (ver. 1.6.17). In addition to bibliometric analysis, the related topic modelling was calculated with Non-Matrix Factorization (NMF) algorithm in Python programming language. Overall, 1140 original articles were published in the selected field in the WoS database within the years 1991-2021. The results demonstrated an ascending growth in the number of publications. The "The University of London", the "London School of Hygiene Tropical Medicine", and the "World Health Organization"Â (WHO) contributed the most to this field orderly. Researchers from the USA with 372 (32.63%), Brazil with 267 (23.42%), and England with 150 (13.2%) documents had the most scientific collaboration on publishing in this regard. The USA and England had the most collaboration in 38 articles in the co-authorship network of countries. Based on topic modelling analysis, five topic clusters, including "maternal mortality", "child and infant mortality", "risk factors related to pregnancy and maternal health", "Geographic Information Systems (GISs)", and "data quality in Health Information Systems (HISs)" were considered for this research. According to the research results, it can be concluded that there is a rising trend in the number of articles published in the field of information systems in maternal health. The USA, Brazil, and England have played a prominent role in scientific production in this regard. Given that this study gives a snapshot of the current status of the research topic and visualizes the collaboration between countries, the obtained results can guide future collaboration and encourage scientific institutes to expand their interactions
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