A knowledge-based semantic framework for query expansion     

Jamal Abdul Nasir  Iraklis Varlamis  Samreen Ishfaq 《Information processing & management》2019,56(5):1605-1617

Searching for relevant material that satisfies the information need of a user, within a large document collection is a critical activity for web search engines. Query Expansion techniques are widely used by search engines for the disambiguation of user’s information need and for improving the information retrieval (IR) performance. Knowledge-based, corpus-based and relevance feedback, are the main QE techniques, that employ different approaches for expanding the user query with synonyms of the search terms (word synonymy) in order to bring more relevant documents and for filtering documents that contain search terms but with a different meaning (also known as word polysemy problem) than the user intended. This work, surveys existing query expansion techniques, highlights their strengths and limitations and introduces a new method that combines the power of knowledge-based or corpus-based techniques with that of relevance feedback. Experimental evaluation on three information retrieval benchmark datasets shows that the application of knowledge or corpus-based query expansion techniques on the results of the relevance feedback step improves the information retrieval performance, with knowledge-based techniques providing significantly better results than their simple relevance feedback alternatives in all sets.  相似文献   

Assessing the response of indigenous loquat cultivar Mardan to phytohormones for in vitro shoot proliferation and rooting     

Nadeem Akhtar Abbasi  Tariq Pervaiz  Ishfaq Ahmed Hafiz  Mehwish Yaseen  Azhar Hussain 《Journal of Zhejiang University. Science. B》2013,14(9):774-784

In vitro cultures of loquat cultivar Mardan were established using shoot apices after treating with NaOCl (5%, 7%, 10%, 12%, 14% (v/v)) for 12 min and HgCl₂ (0.01%, 0.05%, 0.10%, 0.20%, 0.25% (w/v)) for 2 min. A maximum survival rate of 70% was recorded after surface sterilization with 10% NaOCl. Caulogenic response was assessed on Murashige and Skoog (MS) medium fortified with assorted combinations of the cytokinins, benzylaminopurine (BAP), kinetin, and N6-(2-isopentyl)adenine (2iP). Treatment of BAP 1.5 mg/L combined with 2iP 9.0 mg/L and kinetin 1.5 mg/L was found to be optimum for shoot morphogenesis in terms of the number and subsequent growth of shoots, while the highest shoot length was yielded by the combination of BAP 0.5 mg/L, kinetin 0.5 mg/L, and 2iP 3 mg/L. Higher levels of cytokinins induced callogenesis, vitrification and stunted growth to some extent. For rhizogenesis, uniform sized micro-shoots were excised and transferred to half-strength MS medium containing auxins. The best rooting expression was observed with naphthaleneacetic acid (NAA) 1 mg/L combined with indole-3-butyric acid (IBA) 2 mg/L and paclobutrazol (PBZ) 1 mg/L.  相似文献   

Analysis of Feasibility and Acceptability of an E-Learning Module in Anatomy     

Ghulam Mohammad Bhat  Ishfaq Hussain Bhat  Shaheen Shahdad  Saima Rashid  Mudasir Ahmad Khan  Ajaz Ahmad Patloo 《Anatomical sciences education》2022,15(2):376-391

Recent advance in medical education is in correlation with the advances in information technology and thus computer-based learning is being increasingly employed. The objective of the present study was to design and evaluate an e-learning module in anatomy and assess the perceptions of students and faculty about this e-learning module. The participating students were randomized into three groups by block stratified randomization and Google groups were created for each of the three groups. The e-learning module was implemented in three sessions by rotating the three groups. Validated questionnaires were sent to faculty and participating students via Google forms to obtain feedback. The results of ANOVA showed that there was a significant difference among the groups in terms of marks obtained with conventional (F = 2.403, P = 0.103), online (F = 6.050, P = 0.005), and blended (F = 5.801, P = 0.006). Post hoc comparisons using the Tukey HSD test, about the gain of knowledge, indicated that the results were insignificant when comparing the conventional group with the online group, but were significant when comparing the blended group with the conventional and online group. The qualitative data regarding the perception of students toward e-learning were analyzed using thematic analysis. The introduction of an interactive e-learning module in anatomy was effective and well received by the students and faculty. The study showed that blended learning has a positive impact on the students' learning by improving cognitive gain and receptive perception for e-learning.  相似文献