Evaluation of grooving method to postpone debonding of FRP laminates in WPC-FRP beams

The use of lightweight construction material with high corrosion resistance and low cost plays an important role in the design and construction of marine structures such as waterfronts. One of the most common methods for strengthening the structures is composite fibre reinforced plastic (FRP) sheet that is used for member retrofitting including wood plastic composite (WPC). The WPC material is produced from wood and compressed resin, which has good mechanical properties as well as economic benefits. The main problem of WPC reinforced with FRP sheets is the debonding of the sheet from WPC surface, which leads to premature and non-economic failure in members. One of the existing methods to solve this problem is surface preparation. However, surface preparation of wood plastic composite has some additional problems, such as operational cost, environmental pollution, etc. Therefore, to avoid debonding, another method has been used, known as the grooving method at the lower parts of beams. The laboratory used 50 I-shaped specimens with the same geometrical and mechanical properties. Initially, some slots such as longitudinal, transverse and diagonal grooves were created on the surface of specimens and filled by an epoxy. All beams were armed using one or two layers of GFRP sheets embedded at the lower part and were tested under four-point flexural loading. Grooves of different shapes, various widths and depths as well as the number of reinforcement layers were determined for considering their effect on the beam's behaviour. The results expressed that the debonding of FRP sheets can be delayed by selecting the longitudinal grooves with certain width and depth, which also leads to resistance improvement

Research Paper: Development of the Semantic Aspect of Verbs in a Persian-Speaking Child: A Longitudinal Study

Objective Learning “verb” as one of the main components of sentence, has been always a debatable topics in the process of language learning. One of the important issues in “verb” learning is determining its meaning using syntactic clues and learning its semantic aspects. Therefore, the main objective of this study was to examine the development of the semantic aspect of “verb” in a Persian-speaking child. In addition, with regard to similar reports from different languages, the answers to the following question were sought: Does in the process of learning “verb” and the interpretation of its meaning by a Persian speaking child, syntactic clues play a fundamental role? Does the child get help from the syntactic frame of the sentence to decipher the meaning of the verb?  Materials & Methods This research was a case and longitudinal study conducted on a Persian-speaking child  from 21 to 45 months of his age and data were collected naturally in the context of his everyday conversations. After collecting the data (during 24 months), the created verbs were classified based on semantic classification of Lee and Naigles (2005) in 4 semantic classes of motion, internal-communication, bodily process, and creation-performance verbs. Theoretical framework of the research was syntactic bootstrapping of Naigles (1990, 2005), which was an interactive view (semantic-syntactic). Also, the data analysis method of the research was descriptive-analytic. Results The results of the research confirms the syntactic bootstrapping of the “verb” in the growth process of the “verb” learning in Persian-speaking children. So that the Persian-speaking child in his 21 to 45 months old uses the syntactic clues to interpret the meaning of the verb i.e., the syntactic frame of the sentence helps child to interpret the meaning of the verb. Another finding of this research was the order of emergence of verb semantic classes in the language learning process. Based on the study evidence in the process of verb learning of a Persian-speaking child, at first the motion verbs appear that have the highest frequency of occurrence in the process of learning verbs, then come the bodily process, creation-performance, and internal-communication verbs that are produced the least in this age period. The low frequency of internal-communication verbs and not understanding the implicit meaning of some verbs by the child, especially in the early phase of this age period, shows that at first the child’s mind is occupied more by the objective and tangible phenomenon. In other words, the child learns rapidly objective and concrete phenomenon and gradually the child’s mind by learning the tangible and objective words, automatically extract their common features and learns them. One of the significant finding of this research was that the more the child interacts with the social environment, and his cognitive abilities grows, the more will be his/her production of verbs, especially creation-performance verbs. Conclusion Based on the study evidence, the frequency of verb development with respect to semantic aspect in Persian-speaking child is similar to other children who speak other languages and syntactic frame of the sentence helps him/her to decipher the meaning of the verb. It seems that this feature would help to diagnose, evaluate, and rehabilitate the language and speech disorders in the process of verb learning

The Role of non-Linguistic Variables in Production of Complex Linguistic Structures by Hearing-Impaired Children

Objectives: Language development is often very slower in hearing impaired children compared with their normal peers. Hearing impairment during childhood affects all aspects of speech production and language acquisition. It seems that hearing impaired people suffer from language and speech impairments such as production of complex linguistic structures. The purpose of this study is to determine the role of nonlinguistic variables in production of the complex linguistic sentences in children with hearing impairment. Method: Twenty normal children, aged 6-7 years and twenty children with severe to profound hearing impairment, aged 8-12 years were selected in a simple random sampling from normal kindergartens and schools, and exceptional schools for hearing impaired people. This research was a case-control research. The confirmation of the audiologist in the exceptional schools for hearing impaired people and the information recorded in the history of these students were considered in order to determine the kind and degree of hearing loss, and other non-linguistic variables. The production of complex sentences was tested by Elicitation Test. The content validity of the production test was determined and then the reliability was confirmed with Cronbach Alpha Test. Data collected were analyzed by statistical tests such as Pearson's Correlation, Independent Samples T-Test and Mann-Whitney U Test and using SPSS software. Results: The results of this study showed that there was no correlation between the non-linguistic variables such as early detection and early intervention, and production of complex linguistic structures in hearing impaired children. Conclusion: In the first months of life, children have to deal with natural language to create the foundations for linguistic health and complete development of syntax. If language input is not rich and available during the critical period for learning a first language, the syntactic competence cannot grow naturally. Therefore, two non-linguistic variables, early identification and early intervention will be the main predictors for production of complex linguistic structures