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Despite all the efforts of professors and students, learning the four language skills of French in academic institutions has always been accompqnied by challenges. One of these skills is written production, in which students make numerous mistakes. We believe that identifying and analyzing areas of error can be effective in improving their writing skills. In the present study, using an analytical-descriptive method, the written productions of a group of students on a B1 level topic were examined. The data collection tool is the DELF B1 evaluation grid with ten criteria for writing correction. The participants in this study show that 42 percent of students had very good and good averages, and 58 percent had average and weak scores. The target population of this study performed acceptably in only three skills-coherence and logical structure, the ability to present events, and adherence to the topic-out of the ten criteria in the evaluation grid. However, they have not yet achieved the necessary skills in the other seven criteria. The areas of errors revealed in this research could serve as topics for further studies to extract and analyze errors in each domain.
 

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The present article has studied the syntactic errors made by Lak students in Farsi learning/using. At first, types of errors and their occurrence positions were recognized based on Corder (1975) classification. Then, strong and moderate versions of Contrastive Analysis Hypothesis were considered in data analysis. The results indicated that the moderate version had  the dominant role in second language learning. Although this article shows that language learners are affected by some interlingual transfers, the context of learning is the main factor in language learning. Grammatical errors such as overgeneralization, false analogy, approximation  and circumlocution were not highly occurred. So interlingual errors and communicative strategies were not the main sources of errors. The findings also indicated that the more the proficiency the target language, the less will be occurrence of errors. This illustrates that errors are rule-governed and this fact is very important in error analysis researches.    

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Spelling is one of important skills of the second language learning, which deserves to be considered due to its importance and its impact on reading and writing skills. However, this language aspect has been less considered by educational planners and teachers. Learning spelling is a completely systematic process that is influenced by learners’ knowledge on different aspects of language (including phonological, morphological and orthographic knowledge). Through investigating the spelling errors of Persian learners, it is possible to achieve their real understanding from the second language structure at each stage of their linguistic development. Thus findings of such research are useful for teachers, curriculum and textbook designers who are eager to identify problematic areas for Persian spelling learners. The data of present research help them find in which linguistic aspect of spelling, their learners need more training.
The significance of this issue and the lack of literature in this field have led the authors of the present paper to analyze the spelling errors of Arab learners of Persian language by using  contrastive and error analysis approaches. The data collected from 105 of learners’ intermediate and final spelling tests in three levels of beginner, intermediate, and advanced. The population of the present research has been selected by simple random sampling among Farsi-learners at Jam’at-al-Mostafa-al-Alameyyeh , Ghom branch. Regarding errors’ sources, the data obtained divided into three groups of intralingual, interlingual and ambiguous and based on their category, they are classified as consonantal, vowel and form errors. The results indicate that categorically, the errors related to vowel system have the highest frequency (47%) and there aren’t much differences between consonantal (26/8%) and form (26/4%) errors. Also according to the source of errors, the inter lingual errors with the source of mother tongue with 56% have the maximum frequency and ambiguous and intra lingual errors are in the second and third places (26% and 18% respectively) (table 1). Therefore, it can be said that the most important source of spelling errors of Arab learners of Persian is the interference of learners’ mother language on Persian spelling learning. These kinds of errors are resulted from trivial differences between Arabic and Persian phonemic systems. This matter confirms with the moderate version of contrastive analysis.

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Error is a common and yet predictable phenomenon in the process of learning a second language. Traditionally, errors were seen as obstacles in learning a second language. So they should be avoided, but today errors are regarded as important factors in learning a second language. Language interferences are a category of errors that are the result of transferring a native’s language knowledge to the target language. Language transfer may occur in two ways: positive and negative transfer. Positive transfer occurs when there are similarities between source language and target languages. This transfer will help learning a second language. Negative transfer occurs in cases where there are differences between first and second languages and they cause language interferences.

The present research, within the framework of "error analysis" based on Brown (2007) classification of errors, is intended to analyze the syntactic errors that result from the interference between Kalhori Kurdish and Persian in the speech of Kalhori natives. So, among speech errors, syntactic errors, and among them the errors caused by the interference between first language and second language were analyzed. The approach of this study is integrated (quantitative/qualitative). The sample included 170 bilingual Kalhori males and females living in Kermanshah. They were selected via voluntary sampling method. Interviews were held in the presence of interviewees to collect data, during which participants were asked to speak about a memory in Persian.  The results of the study showed that errors from the most frequent to the least frequent were of components of compound verbs, prepositions, order of components in a sentence, “ra”, incorrect verb, using redundant “je”, conjunction and incorrect pronoun. The reason for the occurrence of language interference in the speech of Kalhori natives is that in the mind of language learners, Kurdish language system is completely formed as the first language. According to the transfer theory, the reason for the existence of interlingual errors is the existence of this mental system. At the beginning of learning Persian as a second language, the language learner relies in many cases on his first language. Thus, using first language structure leads to the interference of structures.

The results of the present study can help to present some pedagogical guidelines for teachers, syllabus designers, test constructors and language learners to decrease problems of learning Persian. So if a teacher becomes aware of linguistic findings, such as error analysis, he can figure out why learning is not happening. In addition to that identifying errors helps teachers to evaluate the progress of their students and they become aware of the points they should put more emphasis. Also, the results of this study can help syllabus designers to design books for bilingual students. Since the purpose of the tests is to evaluate students' knowledge, test constructors, with knowledge of the errors recognize where students have difficulty with. In this way, the reason for the problems of bilingual students is not just their lack of attention to the lessons.  Learners themselves can make their assumptions about language through their errors and identify and resolve their linguistic problem.

 
 

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The present study aimed to analyze the frequent errors in the narrations and hadiths translation of Arabic translation students works to categorize their errors, identify the causes of each type of error and explain their correctness method. To this aim, was used descriptive-analytical method based on the Christian Nord's model for categorizing the translation errors. He divided their errors to four groups of semantic, cultural, linguistic, and specific to the text type. Based on this model, the errors of translators in this study were mean occurrence frequency: semantic (98.3%), specific to the text type (94.3%), linguistic (72.5%) and cultural (55%). Similarly, the reason for their errors in any kind is weakness in these themes: "Reconstruction of logical relationships between sentences in translation," "Transferring the meaning of elements specific to the discourse of hadiths and narratives," "Understanding the linguistic construction of sentences and conveying their exact meaning," and "Conveying the implications of cultural interpretations and cultural elements." Correction of these errors in teaching depends on the use of a systematic set of narratives and hadiths that are categorized based on a variety of errors to improve the translation skills of students in solving the challenges of translating these texts regularly by practicing various samples.

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Ttriangulation technique is one of the most commonly techniques used in three dimensional measurements. The depth reconstruction accuracy is a direct impact of the quantization process, and so it is related to the pixel size of the sensor. By decreasing the pixel size, the accuracy can be improved however it will affect the quality of the image as it reduces the SNR. Dithering technique may be used to reduce the errors during quantization. The current study introduces a novel technique in which a relative fine movement between object and sensor is generated during picture capture. The calibration of laser and camera is another important factor affecting the accuracy of the scanner. In this study, the laser is calibrated in high precision with the camera simultaneously without any extra mechanical device. The paper firstly describes the theory of the noise introduction technique followed by modeling and simulation of the process. The results obtained from simulation show great improvement in measurement accuracy. To evaluate the result in a real world, a control rig was designed and built following which experiment were performed. The results showed considerable improvement in measurement accuracy. The result of both simulation and experiments are reported.

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Ttriangulation technique is one of the most commonly techniques used in three dimensional measurements. Hardware and software used in 3D scanning systems are main error sources affected the accuracy of scanners. Depth reconstruction accuracy is a direct impact of the quantization process, and so it is related to the pixel size of the sensor. Dithering technique may be used to reduce the errors during quantization. The current study introduces a technique in which a relative fine movement between object and sensor is generated during picture capture. Although, using this technique will improve the accuracy of scanning but changing the hardware set up during the process is also time consuming. So to deal with this problem the dithering technique is simulated using the linear regression to reduce the scanning time. The paper firstly describes the theory of the noise introduction technique followed by modeling and simulation of the process by regression function. The results obtained from simulation show great improvement in measurement accuracy. To evaluate the result in a real world, a control rig was designed and built following which experiment was performed. The results showed considerable improvement in measurement accuracy. The result of both simulation and experiments are reported.

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In this study, a Lattice Boltzmann Method (LBM) has been developed to calculate the distribution of a scalar quantity, like temperature, in a natural convection flow field under the condition of varying fluid thermal conductivity. The standard form of an LBM usually considers the fluid properties to be constant without any source term in conservation equations. The model developed is to account for variation of thermal conductivity with temperature in the presence of an external heat source. The proposed model has been examined against various case studies. It is shown that it is capable of modeling the extremely nonlinear problems. To magnify the nonlinear term in the natural convection case of under study, the radiation and other thermal sources have been used. The multiple relaxation time scheme has been applied to assure the solution stability. Using Chapman-Enskog analysis, the error associated with the proposed model has been estimated. The part of error which was not due to variations in the fluid properties, may be eliminated by introducing a correction term in higher order terms in Chapman-Enskog analysis. In addition, it has been shown that the correction term associated with the fluid conductivity variations, create an error of second order in terms of Knudsen number and is negligible. The present LBM model has an error of the second order of magnitude with respect to time.

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  The present study has formed in order to determine the current errors source of Persian leaners at beginner, intermediate and advanced levels. this survey tries to give answer to this question: From what source do current errors and mistakes of Persian leaners originate at beginner, intermediate and advanced levels? To this end, some compositions were prepared from Saadi Foundation Corpus in this address: http://sfcorpus.ir. These data were recorded by foundation instructors regarding years (2015-16) on website and
they belong to Persian learning courses held for Arab, Chinese, Pakistani, Indian and Turkish language learners at six levels (Basic, pre-intermediate, intermediate, upper-intermediate, advanced and upper- advanced). Given research subject, 210 compositions, belonged to 5 Persian-learners from Saudi Arabia, China, Pakistan, India and Turkey were elected in several subjects where each Persian learner gave 14 sheets with totally 70 sheets at any learning- level (Beginner, intermediate and advanced). Then, data were analyzed by descriptive method based on Error Analysis Scale (Keshavarz, 1994) and the acquired results were presented both qualitatively and quantitatively. The given findings derived from this analysis showed that the current errors of Persian learners originate from extra lingual source at beginner level and learning strategy is the factor for current error for Persian learner at intermediate level. Finally, the current errors of Persian learners are related to learning texture at advanced level. The analytical results can be addressed by instructors, authors and educational planners for non-Persian speakers so that to recognize better weak points of Persian learners to select appropriate teaching technique and provide educational textbooks.