Production

It is widely acknowledged that collocations play a crucial role in second or foreign language learning by enabling learners to know more about language chunks and lexical strings. Although many studies have examined L2 learners’ collocational competence, comparatively less research has been carried out to probe into the effective instruction and exercises for enhancing the acquisition, retention, and production of lexical (e.g. make a mistake ) vs. grammatical ( on purpose ) collocations. Therefore, the present study attempted to explore the effect of L2 definitions, fill-in-the-blanks, and sentence writing exercises on the acquisition, retention, and production of lexical vs. grammatical collocations. The data were collected from 66 EFL participants who were studying English at a private language institute. First, an Oxford Placement Test (OPT) was given to homogenize the learners. Then, the participants were divided into three groups, each receiving one of the three different types of exercises including definitions, fill-in-the-blanks, and sentence writing exercises. Data analysis using multivariate ANOVA (MANOVA) indicated that learners who received the sentence writing treatment significantly outperformed those learners who received definition and fill-in-the-blank exercises in the acquisition, retention, and production of lexical vs. grammatical collocations. Moreover, fill-in-the-blanks could help the participants learn, retain, and remember both types of collocations significantly better than the L2 definitions. These findings have some pedagogical implications for learning and teaching lexical and grammatical collocations.

Volatility of exchange rate while changes from time to time, is expected to affect firm level operations as well as aggregate level outcomes i.e. macroeconomic performance. This paper, investigates the effects of exchange rate volatility on aggregate production in Iran using a Structural Vector Auto Regressive model with Exogenous Variables (SVARX). The model is estimated based on macroeconomic data during 1990q2-2015q1. Impulse response functions show that realization of a positive shock to the exchange rate volatility-measured by quarterly coefficient of variation derived from daily exchange rate data set rather than common GARCH-based measures- is associated with a significant production drop. These results are robust in reference to changing output measures. We also provide some necessary sensitivity analysis to check robustness of the results with respect to recursive restrictions which are imposed to identify the structural model. After all this robustness checks the model confirmed negative effect of exchange rate volatility on output in Iran's economy. Furthermore, the results show that CPI and exchange rate will significantly increase when exchange rate volatility rises while import declines.

The purpose of this paper is to investigate the system of oil revenues effects on the production performance of oil-rich countries in both short and long-run. To reveal new insight, a macroeconomic model is designed to hypothesize long-run structural relations in the economies of the oil-rich countries including three long-run relationships of real output, real money balance, and the adjusted purchasing power parity and short-run dynamics of variables within the framework of a Vector Error Correction Model. The model is estimated based on the annual data of 33 oil-rich countries during the period of 1992 to 2016. The existence of three long-run relationships in the economies of oil-rich countries is confirmed. Based on the estimated model, the net effect of oil revenues changes on production is directly related to the institutional quality index. In countries with the institutional quality lower than the threshold, the net effect of increasing oil revenues on production in the long-run is negative, and in contrast, in countries with higher institutional quality, this effect is positive and will be strengthened by increasing institutional quality. The institutional quality threshold is estimated to be 0.23.

The purpose of this research is to design a model for the development of optimization of gasoline production in the oil refinery. The research method is experimental, which uses nonlinear programming. The statistical population is the set of sections and pressures of steam, benzene, octane in four different time periods for the production of gasoline products in accordance with the standards of the National Petroleum Products Distribution Company. Version 24.1.2 resolved. The results of determining the amount of slices for mixing in two time periods, the amount of steam pressure, octane and benzene to produce the final gasoline product for each of the nine slices in each time period are shown.. An increase in the amount of benzene in the gasoline product than the standard level causes an increase in the amount of air pollution. On the other hand, reducing the octane number will increase the knocking of car engines and will lead to a decrease in engine efficiency. Exceeding the standard gasoline steam pressure reduces the volume of gasoline consumed by customers and as a result creates customer dissatisfaction.

This research has been done to investigate the relationship between verb comprehension and verb production of Persian learners in Persian language writing as a second language, based on the processes of ideational metafunction in Halliday’s systemic functional grammar. The statistical population was the Persian learners of the international center of teaching Persian to non-Persian speakers in Ferdowsi University of Mashhad. The data collection method was based on field study and random sampling method. The data were gathered through tests, interviews and essays which were divided into two parts: verb comprehension and verb production. The results of the tests were analyzed for verb comprehension, while the outputs of compositions were used in verb production. The collected data then were analyzed by SPSS. The results indicated that there was a positive correlation between comprehension and verb production of mental process at elementary levels. On the other hand, no correlation was found between Persian learners’ verb comprehension and verb production at intermediate level. Furthermore, there was a negative correlation between comprehension and production of the behavioral process at intermediate level and the comprehension and production of the material process at the advanced level. This showed the effect of three factors on creating a positive and negative correlation between processes in foreign Persian learners: 1) the objectivity and subjectivity of processes, 2) the versatility of processes, 3) Persian learners’ language level.

The present study investigates the effectiveness of a conceptual approach, grounded in cognitive linguistics, in enhancing the comprehension and production of phrasal verbs among Iranian EFL learners of English. To this end, 38 participants (16 males and 22 females) at intermediate levels of language proficiency were randomly assigned to an experimental and a control group, and underwent instruction through the conceptual approach or the traditional method, respectively. A pre-test was administered to assess baseline performance, followed by the intervention and two post-tests (i.e., a cloze test and a story-retelling task) to measure changes in comprehension and production of the phrasal verbs. The cloze test measured differences in phrasal verb comprehension, while the story-retelling task assessed production and accuracy. The mixed between-within-subjects ANOVA (SPANOVA) revealed significant improvement in the experimental group on the post-test. Independent sample t-tests confirmed superior performance in the production and accuracy of phrasal verbs for the experimental group. This suggests that the conceptual approach offers a systematic method for learners to approach phrasal verbs analytically, contrasting with the traditional perception of these elements as non-analyzable. As a practical implication, educators in EFL contexts, are strongly urged to adopt the presented conceptual approach. This innovative pedagogical strategy not only enriches the learning experience but also addresses linguistic challenges associated with phrasal verbs, fostering creativity in the instructional process through situational presentations and orientational metaphors.