In this paper we define the Weyl algebra by two ways, and we study some theorems related to this algebra. We also study it widely as a ring of differential operators.

Abstract

Insect host preference by the larval pupal endoparasitoid Opius. pallipes was studied in Ojilate region in western Libya using broad bean (Vecia faba) as a host plant and the two leafmininig species, the American serpentine leaf miner Liriomyza trifolii (Burgess) and the tomato leaf miner Liriomyza bryonia (Kaltenbach). Three peaks of abundance were recorded by O. pallipes on both insect hosts L. bryonia and L. trifolii. On brad bean a peak was exhibited with (81 individuals/ 100 infested leaflets) with L. trifolii whereas a peak of (31 individuals/ 100 infested leaflets) was exhibited with L. bryonia. The lowest count was observed with (33 individuals/ 100 infested leaflets) on L. trifolii and with (27 individuals/ 100 infested leaflets) on L. bryonia. Under laboratory conditions, insect host preference of the parasitoid O. pallipes was tested. The Results indicated that number of eggs and parasitized larvae per parasitoid female were significantly higher on L. trifolii than L. bryonia in the choice test with (9.2±3.9 eggs/female and 7.0±2.9 host larvae/female, on L. trifolii than L. bryonia respectively). On the other hand number of parasitized larvae per female was significantly higher in no choice test with (9.2±2.3 parasitized larva/female and 7.1±3.0 parasitized larva/female, on L. trifolii than L. bryonia respectively)

in Higher education sector, assessment criteria are important in measuring students‟ learning and support teaching. The assessment of students EFL writing could help in identifying students‟ learning needs, progress and also teaching. This research examines university tutors and students understanding of assessment criteria used in EFL writing skills. The analysis shows important finding that most of the tutors did not inform students about assessment criteria or discuss them which affected the students‟ ability to gain higher grades and produce better work. This might be due to lack of knowledge about the importance of providing and involving students in the criteria. The finding prompts a re-thinking about the use of assessment criteria and could make significant contribution to improve and provide great insights into the education especially in the Libyan context and in an EFL context.

In higher education, assessment is a fundamental in measuring students’ 

learning and supporting teaching. The assessment of students’ English as a 

Foreign Language (EFL) writing can help in identifying students’ learning needs, 

progress and teaching. A number of studies have been conducted on 

assessment in the Libyan context; however, these studies have focussed on 

other aspects of EFL teaching and learning and not EFL writing assessment. 

The study, therefore, explores the assessment methods that EFL tutors use in 

assessing their students’ written work. It also aims to examine the factors that 

affect tutors’ choices of assessment methods and identify how students 

perceive the assessment methods concerning the process and product with 

relation to tutors’ thinking.  

To understand this topic from diverse perceptions, questionnaires were distributed to 12 tutors and 207 4th year students, and semi-structured 

interviews were conducted with the sample of 12 tutors and six students 

(purposive sampling). SPSS software was adopted as a means for 

questionnaire analysis, while grounded theory was selected to analyse the 

interview data.  

Both data collection instruments provide a range of interesting findings as tutors 

have experience in summative and formative assessment whereas self and 

peer assessment are not performed by all students. However, there are several 

factors that have a potential effect on the use of a variety of methods of 

assessment. Both tutors and student participants believe that summative 

assessment is a traditional method which has little effect on EFL writing skills. 

ii 

Concerning the process and product of assessment, students have a deficiency 

of receiving assessment criteria while tutors’ feedback is valued by all students 

and also grades are perceived as the main product of assessment by all 

participants. Further results indicate that all students agree that they have a lack 

of involvement in discussion group-assessment, feedback, criteria, standards, 

learning goals, self-grading and peer-grading. This is due to several factors that 

limited students being involved in such concepts in relation to assessment. For 

example, Libyan tutors still view assessment as being under their control, which 

restricted the opportunity for students to be involved in assessment. The key 

finding is the relationship between criteria, feedback and grades, as an 

example, without known criteria the students do not know what is being 

assessed, and the feedback is too broad because it covers every aspect of 

assessment.  

Therefore, a contribution to knowledge is made by adding and expanding the 

current body of knowledge about assessment methods used in the Libyan EFL 

context. This study is important because it offers critical interpretations of what 

methods are used to assess students’ written work in terms of the process and 

product, and the knowledge gained from this study could be used to improve 

the effectiveness and efficiency of assessment methods not only in the Libyan 

context but also other second language users (L2) learning context.