Showing 11 results for Zhou
Volume 5, Issue 3 (9-2017)
Abstract
Background: In this study for the first time terrestrial laser scanning survey was implemented on upland Hyrcanian forest, through which a and new method was applied to automatically extract DBH and tree position as a necessary step for height calculation and fitting the clustering as a circle.
Materials and Methods: Tree height extracted by fixing a cylinder around the trees center. The accuracies of these methods were investigated by field measurement. Among 4 shapes fitting algorithm, Monte Carlo had more suitable result to fitting circle in each height above the ground.
Results: Tree detection rates were 85% for Carpinus betulus and 87% for Diyospyrus lotus with respect to field measurement. R2 and RMSE for DBH measurement were 0.98, 2.06 cm for Carpinus betulus and 0.98, 1.26 cm for Diyospyrus lotus. Value of R2 and RMSE for height measurement were 0.96, 3.37 meters and 0.93, 3.02 meters for Carpinus betulus and Diyospyrus lotus, respectively.
Conclusions: The accuracy of DBH by TLS is very suitable, and about the height of trees we extracted underestimated value in comparison to field measurement and that we need to develop more effective algorithms in order to reach more accurate measurement of trees’ height in Hyrcanian forest.
Volume 6, Issue 1 (No.1 (Tome 22), (Articles in Persian) 2015)
Abstract
The purpose of this paper is to examine the role of semantic and syntactic rā morpheme in Sorani Kudish based on Van Valin’s (1996, 1997, 2007) Role and Reference Grammar. In this paper, it is shown that attaching –rā to the verb causes to absent all specific roles related to actor, e.g. agent, force, instrument and other specific roles such as experiencer, performer, consumer, etc. in the syntax level. These specific roles directly affect the undergoer. Since in all of the mentioned cases, the manifestation of -rā causes to the absence of actor in the syntax level, the crucial role of this morpheme is an anti-actor. In terms of semantic properties of NP, the more agency of NP, the more attaching –rā to the verb. Although the manifestation of -rā often occurs in the sentences containing two-argument verbs. It also occurs in intransitive sentences containing actor, and causes to the absence of the actor. Moreover, based on the presence of –rā morpheme in a structure, it further plays the role of a non-active morpheme, and it is shown that all non-active structures have semantically actor.
Volume 7, Issue 2 (No.2 (Tome 30), (Articles in Persian) 2016)
Abstract
The purpose of this study is to examine the passive in Sŏranī and Kurmanji Kurdish based on Role and Reference Grammar. The strategy of the research is analytic-comparative. Sŏranī and Kurmanji, respectively, manifest morphological and periphrastic passive voice. In Sŏranī (Mahǎbǎdi) passive is marked by suffix rǎ/rě attached to a verb and in Kurmanji by the auxiliary verb hǎtin "to come" along with infinitive. In this study, it is shown that despite the past transitive constructions in Kurmanji and Sŏranī, respectively, display ergative morphology and non-accusative (neither ergative nor accusative), the passive is insensitive to the tense, namely, passive in the past and present tenses follows the same pattern of accusative languages and it shows that passive construction canonically involve two phenomena of the universal formulation of basic voice oppositions in Van Valin (2007): privileged syntactic argument (PSA) modulation and argument modulation. Furthermore, this study shows that the Role and Reference Grammar approach cannot make a clear account about those non-active structures that form from intransitive complex verbs.
Volume 12, Issue 5 (November & December, (Articles in English & French) 2021)
Abstract
Empirical studies examining the effects of language learning have largely focused on linguistic changes in learners. Regrettably, this has left the non-linguistic changes under-researched. To address this, the current study examined what self-identity changes Chinese university EFL learners experienced and how individual characteristics (i.e., gender, starting age of study, and university major) may have affected these changes. To do so, a self-identity change questionnaire was administered online to 416 Chinese university students using a convenience sampling strategy. Seven identity change variables were measured by the survey: changes in (1) positive self-confidence, (2) negative self-confidence, (3) productive identity change, (4) additive identity change, (5) zero change, (6) subtractive change, and (7) split change. Confirmatory factor analysis confirmed that the items on the questionnaire measured their intended identity change variable. Descriptive statistics showed that participants experienced changes in self-confidence, additive identity, and productive identity, but did not experience subtractive or split change. The results also showed that the participants were unaware that they had experienced any changes. Multiple analysis of variance results showed that the individual characteristics contributed to some variation in the identity changes. The findings support theories suggesting that language learning contributes to non-linguistic changes within learners.
Volume 14, Issue 2 (May & June 2023 2023)
Abstract
Flipped classroom is one of the relatively new teaching methods in which teaching takes place outside the classroom and class time is devoted to practice, and learning is established under the supervision of the teacher. Various studies in the world and in Iran have examined the effectiveness of flipped learning in teaching English, but these studies have been done either in the context of schools and institutes or with English language college students. This study examines students’ attitudes towards the flipped classroom, and the effectiveness of flipped learning in General English courses at Farhangian University. Findings show that students are satisfied with the flipped classroom and prefer it to traditional classes. Based on the results of paired and independent t-tests, flipped learning improves students' learning in General English courses. In addition, gender can affect the effectiveness of flipped learning, but students' field of study does not have such a role. Based on the findings of this study, flipped learning can used to increase the effectiveness of General English courses in face-to-face and virtual classes.
1. Introduction
Successful teaching and the improvement of learners’ achievement is undoubtedly the goal of all educational systems, and the advent and availability of technology to the public, has made this goal more attainable in recent years. Flipped classroom model is one of the innovations in teaching made possible through technology, which is an attempt to respond to challenges in traditional teaching by devoting more time to active learning in the classroom using a blended learning approach. In flipped classroom model, the direct teaching presented to the whole class changes into interactive personalized teaching which occurs outside the classroom, and hence the classroom becomes a dynamic and interactive learning environment to consolidate learning (Kaviani et al., 2018).
Although many studies have studied the effectiveness of flipped learning in schools and language institutes in Iran, and in college contexts overseas, no rigorous study has been devoted to this issue in university contexts in Iran till the date of conducting this study. Therefore, this study aimed to investiage the effectiveness of flipped learning in a general English course in Farhangian University, and also to review students reactions to this experience.
2. Methodology
In this study, which was conducted in the second semester of the academic year 2017-2018 at Farhangian University of Mashhad, eight general English Language classes of the undergraduate course in Shahid Beheshti Campus (males) and Shahid Hasheminejad Campus (females) were randomly selected to participate in the research. These classes included 300 students (103 females and 197 males) from different fields of study in humanities and science.
The teaching in the classes was done following flipped format until the mid-term exam, and then, classes were taught through traditional methods. In this way, each of the students had two scores, one of which was obtained after the reverse training and the other after the traditional training.
A mid-term and a final exam were used in the research, each of which consisted of 50 multiple-choice, short-answer, and essay-type items. The tests measured knowledge of vocabulary, grammar, and reading and comprehension of the learners. At the end of the semester, the attitude questionnaire about the flipped classroom, which was adapted and translated from the study of Hsieh, et al. (2017) was administered to the students.
3. Results
These results showed that the students were satisfied with their experience in the flipped classroom. According to Hsieh, et al. (2017), the items in the questionnaire measure four aspects of motivation, effectiveness, participation and overall satisfaction of learners. They did not provide items that measured each construct, but since all items had means above the midpoint of the scale, the findings suggest that students believed that the flipped classroom motivated them, and it has been more effective and attractive for them.
Moreover, the results of the paired t test to compare the performance of the flipped and tranditiona classrooms (t = 8.08, df = 299, p<0.05), showd a significant difference between the students' grades obtained after reverse education and the grades obtained from traditional education.
To study the effectiveness of flipped classroom for the two genders , an independent samples t-test was run. According to the results (t=-2.14, p<.05), there was a significant difference between the scores of women and men as a result of flipped learning, and women had a higher mean. This indicates that flipped classroom has been more effective for women.
4. Discussion
The results of this study about students' satisfaction with the flipped classroom are in line with the findings of other survey studies about the flipped classroom using other questionnaires (Baker, 2000; Lage et al., 2000; Mehring, 2015).
The finding of he effectiveness of flipped learning is consistent with theoretical discussions about the effectiveness of the reverse method (Bergman & Sams, 2012; Kim et al., 2018). The better performance of students in flipped classroom is also in line with the results of other studies conducted in the field of English language teaching and flipped learning (Farsi et al., 2020; Hsieh, 2017; Hung, 2014; Sahragard et al., 2020).
5. Conclusion
According to the findings of this research, one of the effective ways to improve English learning in general language classes in the university, regardless of the field of study, is to use flipped learning so that students who have different backgrounds can wathc the teaching video as many times as they need before coming to the class, and use the opportunity to practice in the classroom to consolidate learning and solve possible problems.
Volume 17, Issue 1 (1-2015)
Abstract
Cadmium (Cd), known as a non-essential heavy metal, can cause oxidative stress in plants. In this study, an attempt was carried out to find out whether Cd-induced oxidative and microscopic changes could be observed in the early stage of seedling growth. Seeds of Brassica napus (cvs. Zheda 619 and ZS 758) were germinated in vitro at 0, 100, 200, 300, and 500 μM Cd concentrations in dark for 48 hours. Results showed that the higher concentration of Cd (500 μM) significantly reduced plant growth in both cultivars. However, Cd concentration in both cultivars increased linearly with the Cd concentration, but was more pronounced in ZS 758 than the other cultivar. Moreover, Cd caused oxidative stress in germinated seeds by increasing reactive oxygen species, however, no relationship was found between antioxidative defense capacity including catalase, peroxidase, superoxide dismutase and glutathione reductase activities and Cd tolerance in the two cultivars. Cd toxicity showed significant ultrastructural changes in germinated seed cells, but cell structure in Zheda 619 did not show any difference, while cell structure in ZS 758 was totally damaged under higher concentration of Cd (500 μM). Based on the present findings, it can be concluded that cultivar Zheda 619 showed comparatively higher tolerance and integrity of cell organelles under Cd stress.
Volume 17, Issue 3 (5-2015)
Abstract
The objective of this study was to explore the microbial community diversities and the relationships between microbial community compositions and hydrochemical factors in nitrate contaminated groundwater of Hun River alluvial plain. The method of polymerase chain reaction (PCR)-denaturing, gradient gel electrophoresis (DGGE) gene fingerprints combined with canonical correspondence analysis（CCA） were applied. The Operational Taxonomic Units (OTUs) of all the sampling sites had a certain degree of heteroplasmy and 75% OTUs presented in less than half of the sampling sites. The un-weighted pair group mean average (UPGMA) cluster analysis showed that the microbial community similarity of all the sampling sites were not relatively high (0.6-0.8). The distribution of microbial community positively correlated with nitrate. The dominant bacteria of the nitrate contaminated groundwater mainly included Hyphomicrobium denitrifican sp., Halanaerobium praevalens sp., Desulfotomaculum reducens sp., Nitrosospira multiformis sp., among which the Nitrosospira multiformis sp.and Sulfurovum sp. existed in all the sampling sites. CCA results indicated that Mn2+and NO3- were the most relevant hydrochemical factors to regulate the microbial composition in nitrate contaminated groundwater of this area, and next were Fe2+ and SO42- . The results could provide references for the bioremediation of the nitrate contaminated groundwater of Hun River alluvial plain
Volume 18, Issue 4 (7-2016)
Abstract
Lipases are known to have important functions in many physiological processes in plants. Here, we cloned a lipase gene via Rapid Amplification of cDNA Ends (RACE) technique from Brassica napus L., designated as BnDIL1 (B. napus Desiccation-Induced Lipase 1). The lipase enzyme activity was confirmed by estimating the lipase activity and reduced lipids content in Saccharomyces cerevisiae (pep4)transformant. Two B. napus lines with different oil contents were employed to examine the transcription profiles of BnDIL1 during the processes of seed morphogenesis, maturation, dormancy, pregermination and germination. The transcription level of lipid degradation pathway was enhanced during the processes of seed maturation, dormancy, pregermination and germination, and was higher in seeds of low oil-contents line than that of high oil-contents line. However, BnDIL1 was significantly activated when seed desiccation started. Both “slow desiccation” and “fast desiccation” treatments on seedlings dramatically activated the transcription of BnDIL1, while only “slow desiccation” stress, which would induce the cell apoptosis, significantly activated the transcription of lipid degradation gene. This result demonstrated that BnDIL1 in B. napus was desiccation stress dependent gene rather than fatty acids degradation gene.
Volume 20, Issue 3 (5-2018)
Abstract
Using cotton cultivar that undergoes premature senescence in the late stage of growth, we studied the effects of removing two basal fruiting branches of two cotton varieties, namely, Quanyin-2 and Jiza-999, on the leaf area index, the SPAD value of leaf subtending cotton boll, and the development of cotton fiber in the late stage of cotton growth. We focused on the differences in cotton cellulose accumulation and fiber-related enzyme activities after removal of the basal fruiting branches and the development of cotton fiber during premature senescence. The results showed that removing the basal fruiting branches can maintain the green leaf area of the cotton canopy and the SPAD value of the subtending leaf during the late stage of reproductive growth. The period of rapid accumulation of fiber cellulose lasted longer in plants from which the basal fruiting branches had been removed, and the beginning and end of the rapid accumulation period was later than in the control group with premature senescence.
The activities of cellulose synthesis-related enzymes (sucrose phosphate synthase, sucrose synthase, β-1,3-glucanase, and invertase) were higher in plants in which the basal fruiting branches had been removed than in the control group after 10 days post-anthesis. Removing the basal fruiting branches can optimize the accumulation of cellulose in cotton boll during the late growth stage and mitigate the effects of premature senescence on cellulose synthesis.
We found that the peak values for cotton fiber development-related enzyme activities in the control group occurred earlier, which tended to bring cotton fiber development forward and negatively impacted fiber yield.
Volume 20, Issue 8 (August 2020)
Abstract
The composites derived from the bioactive glasses, such as BG/polysulfone, have better mechanical properties than pure materials and their characteristics are closer to human bone. In this study, the unknown fracture behavior of 58s BG/PSF composite has been investigated. The extended finite element method (XFEM) was used, in order to model the fracture behavior of 58s BG/PSF composite with greater accuracy. The XFEM doesn’t require remeshing at each step and achieves the precise approximation of singularities by incorporating discontinuity behavior into the elements using the enrichment functions. The aim of using the XFEM was to obtain stress intensity factors, displacements, stress and strain around the crack tip, fracture toughness as well as strain energy release rate. Moreover, the 58s BG/PSF composite with 30% bioactive glass particles was synthesized using solvent casting method and the bending failure test was performed according to the relevant standard. Also, to demonstrate the quality of the interface between the glass particles and polysulfone, SEM investigation was performed on the fracture surface. The obtained fracture toughness was in the range of 1.4 to 1.6
, and the strain energy release rate was in the range of 1600 to 1900 J.m
-2, which was comparable to the same properties of natural human bone. Besides, the stress intensity factors and strain energy release rates were calculated by coding in MATLAB and modeling in ABAQUS, and the numerical results were validated with the analytical and experimental data and it was revealed that the numerical results were in great coordinance with the analytical and experimental results.
Volume 21, Issue 3 (5-2019)
Abstract
Wild pepper (Capsicum frutescens L.) could be a source of variation to improve cultivated pepper due to its unique traits with adapting challenges caused by adversity. Interspecific hybridization has been used as an effective way of pepper introgression breeding, which transfers genes of interest from wild relatives to cultivated crops. Here, eight fertile hybrids F1 were produced from pepper (Capsicum annuum L.) and the wild relative (C. frutescens), as female and male, respectively, by interspecific hybridization. Interspecific hybrids were identified using conventional morphological descriptors and SSR molecular markers. The results showed that significant differences in agronomic traits existed among cultivated pepper, wild relatives, and interspecific hybrid F1. Interspecific hybrid F1 presented intermediate values, although they were closer to the wild species in most of the agronomic traits. Analysis of SSR markers clearly showed that interspecific hybrid F1 had bands from the paternal and maternal accessions, which indicated that F1 hybrid was heterozygous. Our results provide hybrid for breeder to transfer genes of interest from wild relative, C. frutescens, to cultivated pepper, which is an important step for introgression breeding.
