مطالب

Total Perceptible Water (TPW) is an important parameter in climatology and weather forecasting and is directly related to any climate process. There are three approaches to estimate this parameter i.e. using radiosonde, using GPS and calculating from satellite images where the first two are localized and the last one can give an instant view of TPW in a vast region. The algorithm used for the TPW calculation from MODIS images is related to the ratio of the reflectance in a water vapor absorbing channel and the reflectance in a non-absorbing channel. Due to strong horizontal variation in the surface reflectance in non-absorbing channels, the retrieved TPW varies strongly from one pixel to its neighboring pixels while it is believed that the horizontal gradient of TPW is very weak. To solve this problem, a damping coefficient was added to the non-absorbing channel reflectance. It is found that this coefficient differs for different surface covers. The current work presents a procedure for calculating these coefficients. The results of a comparison between modified TPW and those extracted from GPS data showed a R 2 of 0.81 whilst this was about 0.67 for non-modified MODIS TPW.

One of the most important necessities that victimology requires at least within criminal sciences is to create a general theory describing and explaining all concepts, theories and hypotheses which may be used in this scientific sphere. The present article seeks to introduce such a theory, using key terminologies formed the literature and content of victimology from beginning of its emergence since mid of the twentieth century. The new discipline of criminal sciences that I argue in this article has emerged in the light of two criminological and legal approaches. The work of the victimology theory is to incorporating these approaches into a unified field of study which is based upon three key concepts: active personality of victim, nature of victimhood/victimization and passivity of victim. In my final considerations, I conclude that the victimology theory can have virtues and advantages including in criminal etiology, preventing victimization and offending and overall formulating a better criminal policy and criminal justice system in practice.

The present study was conducted to evaluate data driven learning (DDL) combined with Computer Assisted Language Learning (CALL) as an approach to improving vocabulary knowledge of Iranian postgraduates majoring in teaching English, English literature and translation. The purpose was to help language learners get familiar with DDL as a student-centered method taking advantage of a computer program for enhancing the knowledge of vocabulary. This research paper analyzed the efficiency of DDL from different angles including the participants' ability to remember the word meanings and make meaningful and grammatical sentences after doing DDL exercises using the Microsoft Power Point program. The results of the study showed that this technique could significantly enhance the participants' vocabulary knowledge in all the above mentioned aspects. The analysis of the questionnaire given to the participants to elicit their attitudes towards DDL showed that most of them were interested in this technique. The results of this article can be helpful for the language teachers who teach the learners at advanced levels of language proficiency and advanced students who would like to learn new items of vocabulary on their own.

Based on the controversial beliefs among L2 teachers about effective corrective feedback (CF) strategies, recast and prompts as 2 kinds of CF have drawn the attention of L2 researchers(e.g., Braidi, 2002; Iwashita, 2003; Loewen & Philp, 2006; Panova & Lyster, 2002; Sheen, 2004). Despite these numbers of studies, debate continues to exist about their usefulness as a CF technique. Whereas recasts provide a correct reformulation of L2 learners’ nontarget utterance, the other alternative type of feedback in L2 classroom settings is referred to as prompts (Lyster, 2004) because they provide signals that prompt L2 learners to self-repair rather than provide them with a correct reformulation of their nontarget utterance. Hence, the focus of this study was to examine the effect of recasts in comparison to prompts on the learning of English third person singular marker “s” by Iranian preintermediate L2 learners. Two CF techniques of recasts and prompts were utilized in 2 experimental groups in response to their errors in using the correct form of the verb for third person singular subject. In the third group as the control group, No-CF was provided by the L2 teacher. The results revealed that the Prompts Group had outperformed the Recast Group and No-CF Group. Thus, it could be concluded that prompts as a CF strategy led to more gains than CF that provided the L2 learners with the correct form (recast) than No-CF.  

Audiovisual devices such as satellite and conventional televisions can offer easy access to authentic programs which are considered to be a rich source of language input for SLA (Second Language Acquisition). The immediacy of various audiovisual programs ensures that language learners’ exposure is up-to-date and embedded in the real world of native speakers. In the same line, in the present paper, some anecdotal as well as experimental studies conducted to highlight the pedagogical values of various audiovisual programs such as news broadcasts, movies, cartoons, series and documentary films are reviewed. The related literature indicates that most of the studies are anecdotal which highlight the pedagogical values of various audiovisual programs as sources of authentic language input particularly in an EFL context where access to social interaction in English as a potential source of language input is limited. As a result, teachers are encouraged to expose the language learners to various audiovisual programs to enhance second language acquisition.