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231.
Mohammad M. N. Esfahani Mark D. Tarn Tahmina A. Choudhury Laura C. Hewitt Ashley J. Mayo Theodore A. Rubin Mathew R. Waller Martin G. Christensen Amy Dawson Nicole Pamme 《Biomicrofluidics》2016,10(1)
The ability to engage and inspire younger generations in novel areas of science is important for bringing new researchers into a burgeoning field, such as lab-on-a-chip. We recently held a lab-on-a-chip workshop for secondary school students, for which we developed a number of hands-on activities that explained various aspects of microfluidic technology, including fabrication (milling and moulding of microfluidic devices, and wax printing of microfluidic paper-based analytical devices, so-called μPADs), flow regimes (gradient formation via diffusive mixing), and applications (tissue analysis and μPADs). Questionnaires completed by the students indicated that they found the workshop both interesting and informative, with all activities proving successful, while providing feedback that could be incorporated into later iterations of the event. 相似文献
232.
Mohammad Tubishat Norisma Idris Mohammad A.M. Abushariah 《Information processing & management》2018,54(4):545-563
Sentiment analysis is a text classification branch, which is defined as the process of extracting sentiment terms (i.e. feature/aspect, or opinion) and determining their opinion semantic orientation. At aspect level, aspect extraction is the core task for sentiment analysis which can either be implicit or explicit aspects. The growth of sentiment analysis has resulted in the emergence of various techniques for both explicit and implicit aspect extraction. However, majority of the research attempts targeted explicit aspect extraction, which indicates that there is a lack of research on implicit aspect extraction. This research provides a review of implicit aspect/features extraction techniques from different perspectives. The first perspective is making a comparison analysis for the techniques available for implicit term extraction with a brief summary of each technique. The second perspective is classifying and comparing the performance, datasets, language used, and shortcomings of the available techniques. In this study, over 50 articles have been reviewed, however, only 45 articles on implicit aspect extraction that span from 2005 to 2016 were analyzed and discussed. Majority of the researchers on implicit aspects extraction rely heavily on unsupervised methods in their research, which makes about 64% of the 45 articles, followed by supervised methods of about 27%, and lastly semi-supervised of 9%. In addition, 25 articles conducted the research work solely on product reviews, and 5 articles conducted their research work using product reviews jointly with other types of data, which makes product review datasets the most frequently used data type compared to other types. Furthermore, research on implicit aspect features extraction has focused on English and Chinese languages compared to other languages. Finally, this review also provides recommendations for future research directions and open problems. 相似文献
233.
The present study investigates English language teaching (ELT) curriculum planning in Iran's Ministry of Education and its implementation by teachers. We studied programme evaluation; needs analysis; the ELT-specific documents; communication channels between planning and practice levels; teacher evaluation and student assessment; interpretation and re-examination of national policies within the Ministry; and the criteria set for ELT material development. Instrumentation included: curriculum documents; interviews with Ministry officials, material developers and headteachers; and teacher questionnaires. Results attested to the lack of any ELT-specific document for material development and absence of research-based needs assessment as the foundation of the programmes. Also, there are no pre-defined linguistic and professional criteria for evaluating teachers, and planning for students' assessment is limited to a set of general guidelines. Moreover, there is neither a programme evaluation nor an ELT evaluation model and national-level policies are not re-examined at planning level. Results also indicate that politico-ideological beliefs of material developers are as important as their expertise and communication channels between planning and practice levels are of a top-down nature. It is argued that the gap between planning and practice results from a highly centralised policymaking process in which local policymakers (i.e. teachers) are not involved. 相似文献
234.
European Journal of Psychology of Education - Theoretical developments in second or foreign language motivation research have led to a better understanding of the convoluted nature of motivation in... 相似文献
235.
Reza Gharibi Amir Hossein Rasekh Mohammad Hadi Sadreddini Seyed Mostafa Fakhrahmad 《Information processing & management》2018,54(6):1058-1076
Bug reports are an essential part of a software project's life cycle since resolving them improves the project's quality. When a new bug report is received, developers usually need to reproduce the bug and perform code review to locate the bug and assign it to be fixed. However, the huge number of bug reports and the increasing size of software projects make this process tedious and time-consuming. To solve this issue, bug localization techniques try to rank all the source files of a project with respect to how likely they are to contain a bug. This process reduces the search space of source files and helps developers to find relevant source files quicker. In this paper, we propose a multi-component bug localization approach that leverages different textual properties of bug reports and source files as well as the relations between previously fixed bug reports and a newly received one. Our approach uses information retrieval, textual matching, stack trace analysis, and multi-label classification to improve the performance of bug localization. We evaluate the performance of the proposed approach on three open source software projects (i.e., AspectJ, SWT, and ZXing) and the results show that it can rank appropriate source files for more than 52% of bugs by recommending only one source file and 78% by recommending ten files. It also improves the MRR and MAP values compared to several existing state-of-the-art bug localization approaches. 相似文献
236.
237.
ABSTRACTThis paper analyzes the process of crack saturation, which is fundamental to understanding why panel paintings have survived remarkably well in the uncontrolled environments of historic houses or places of worship for several centuries. The process of crack saturation was analyzed using finite element modeling. A double layer elastic model with fractured overlying paint layer was subjected to uniaxial tension. The critical separation between cracks was determined and compared with patterns observed in real paintings. In addition, the generation and propagation of delamination were studied to elucidate the effect of their propagation on the saturation distance of cracks, as well as the load carrying ability of the paint layer. Contributing modes of crack propagation and their significance are also discussed. The results demonstrate that shearing fracture mode dominates the process of delamination. The impact of crack saturation on the degree of relative humidity variation that is allowable is also discussed. 相似文献
238.
Seyed Ebrahim Alavi Maedeh Koohi Moftakhari Esfahani Soheil Ghassemi Azim Akbarzadeh Gholamhossein Hassanshahi 《Indian journal of clinical biochemistry : IJCB》2014,29(1):84-88
Breast cancer is one of the most frequent cancer types within women population. Hydroxyurea (HU) is a chemotherapy compound for treatment of patients with cancer diagnosis, including breast cancer associated with several adverse effects. In this study, we applied nanotechnology to decreased drug side effects along with improvement of therapeutic index. Liposomation is widely used in modern pharmacological developments in order to enhance the effects of the drugs. To achieve this, in this study a mixture of phosphatidylcholine and cholesterol was made up and HU was added to the resultant mixture, was then pegylated using Polyethylene Glycol 2000 to increase resistance, applicability and solubility. The mean diameters of nanoliposomal and pegylated nanoliposomal HU were measured by Zeta sizer device and obtained about 402.5 and 338.2 nm. The efficiency of non-pegylated and pegylated liposomal HU was 70.8 and 64.2, respectively. Releasing HU in both formulations was estimated about 25.8 and 21.7 %. Also, this study investigated the cytotoxicity effect of nanoliposomal and pegylated nanoliposomal HU using MTT assay. Results of this investigation showed that the cytotoxic properties of pegylated HU was 3.6 % more than those non-pegylated form, while was 38.93 % more than ordinary from of HU. This study showed that the stability, releasing pattern and cytotoxicity of the pegylated nanoliposomal HU is better than that of nanoliposomal HU. 相似文献
239.
Mahmood Hussain Shah Hamid Reza Peikari Norjaya M. Yasin 《International Journal of Information Management》2014
Despite the critical role of individuals’ perceived security in an online environment, previous research has not attempted to comprehensively study the influences and interrelations between the determinants of online individuals’ perceived security. This research employs five theories to examine the interrelations that might exist between the antecedents of individuals’ perceived security in online environment in Malaysia. It is the first attempt to empirically examine the interrelations of the confidentiality related factors identified in the literature which is a significant original contribution. A questionnaire was the primary research methodology and structural equation modeling was employed to test the hypotheses. The findings suggest that individuals’ perceptions about security are significantly influenced by their perceived technical protection while technical protection was found to be influenced by website design features. Moreover, it was found that individuals’ perceptions toward internally provided assurances are highly influenced by externally provided assurances. However, the results found no significant relations between internally and externally provided assurances about a website's security. The findings imply that e-retailers should launch well-designed websites and communicate the technical protection capabilities of their websites to address individuals’ security concerns. The results also suggest that e-traders should consider the factors influencing individuals’ security perceptions when designing/developing their websites. 相似文献
240.
Walaa Sayed Mohammad Osama Ragaa Abdelraouf Salam Mohamed Elhafez Nagui Sobhi Nassif 《Journal of sports sciences》2013,31(10):934-939
AbstractIn this study, we compared the isokinetic torques of hip flexors/extensors and abductors/adductors in soccer players suffering from osteitis pubis (OP), with normal soccer players. Twenty soccer male athletes with OP and 20 normal soccer athletes were included in this study. Peak torque/body weight (PT/BW) was recorded from hip flexor/extensor and abductor/adductor muscles during isokinetic concentric contraction modes at angular velocity of 2.1 rad · s?1, for both groups. The results showed a significant difference between the normal and OP groups for hip flexors (P < 0.05). The normal group had significant, lower PT/BW value than the OP group for their hip flexors (P < 0.05). The hip flexor/extensor PT ratio of OP affected and non-affected limbs was significantly different from that of normal dominant and non-dominant limbs. There were no significant differences between the normal and OP groups for hip extensor, adductor and abductor muscles (P > 0.05). Regarding the hip adductor/abductor PT ratio, there was no significant difference between the normal and OP groups of athletes (P > 0.05). The OP group displayed increase in hip flexor strength that disturbed the hip flexor/extensor torque ratio of OP. Therefore, increasing the hip extensor strength should be part of rehabilitation programmes of patients with OP. 相似文献