Concept hierarchy across languages in text-based image retrieval: a user evaluation

The University of Sheffield participated in Interactive ImageCLEF 2005 with a comparative user evaluation of two interfaces: one displaying search results as a list, the other organizing retrieved images into a hierarchy of concepts displayed on the interface as an interactive menu. Data was analysed with respect to effectiveness (number of images retrieved), efficiency (time needed) and user satisfaction (opinions from questionnaires). Effectiveness and efficiency were calculated at both 5 minutes (CLEF condition) and at final time. The list was marginally more effective than the menu at 5 minutes (no statistical significance) but the two were equal at final time showing the menu needs more time to be effectively used. The list was more efficient at both 5 minutes and final time, although the difference was not statistically significant. Users preferred the menu (75% vs. 25% for the list) indicating it to be an interesting and engaging feature. An inspection of the logs showed that 11% of effective terms (i.e. no stop-words, single terms) were not translated and that another 5% were ill translations. Some of those terms were used by all participants and were fundamental for some of the tasks. Non translated and ill translated terms negatively affected the search, hierarchy generation and, results display. More work has to be carried out to test the system under different setting, e.g. using a dictionary instead of MT that appears to be ineffective in translating users’ queries that rarely are grammatically correct. The evaluation also indicated directions for a new interface design that allows the user to check query translation (in both input and output) and that incorporates visual content image retrieval to improve result organization

P-n junctions formed in gallium antimonide

Vapor phase deposition process forms a heavily doped n-region on a melt-grown p-type gallium antimonide substrate. HCl transports gallium to the reaction zone, where it combines with antimony hydride and the dopant carrier, hydrogen telluride. Temperatures as low as 400 degrees C are required

Controlled substrate cooling improves reproducibility of vapor deposited semiconductor composites

Improved substrate holder preferentially provides more uniform substrate cooling and increases the proportion of vapor flowing over the substrate during growth. Nitrogen gas is constricted in the substrate holder to cool the substrate

Growth of single-crystal gallium nitride

Use of ultrahigh purity ammonia prevents oxygen contamination of GaN during growth, making it possible to grow the GaN at temperatures as high as 825 degrees C, at which point single crystal wafers are deposited on /0001/-oriented sapphire surfaces

Vapor Phase Growth Technique and System for Several III-V Compound Semiconductors Interim Scientific Report

Vapor phase crystal growth and preparation of gallium, indium, arsenic, phosphorous, and antimony alloy semiconductor material

Vapor phase growth technique and system for several 3-5 compound semiconductors Quarterly technical report

Single vapor phase growth system for preparing semiconductor material

Investigating cluster stability when analyzing transaction logs

© 2016 ACM.Data-driven approaches have become increasingly popular as a means for analyzing transaction logs from web search engines and digital libraries, for example using cluster analysis to identify common patterns of search and navigation behavior. However, steps must be taken to ensure that results are reliable and repeatable. Although clustering patterns of user interaction behavior has been previously explored, one aspect that has received less attention is cluster stability that can be used to aid cluster validation. In this paper we compute stability based on the Jaccard coefficient to investigate the cluster stability when using different subsets of transaction log data from WorldCat.org. Results provide insights into different types of search behaviors and highlight that clusters of varying degrees of stability will result from the clustering process. However, we show that additional investigation beyond the results of cluster stability is required to fully validate the resulting clusters

Researching creatively with pupils in Assessment for Learning (AfL) classrooms on experiences of participation and consultation

This paper reports on an ESRC TLRP project, Consulting Pupils on the Assessment of their Learning (CPAL). The CPAL project provides an additional theoretical perspective to the ‘educational benefits’ perspective of engaging pupil voice in learning and teaching (Rudduck et al., 2003) through its exploration of pupil rights specifically in relation to assessment issues presently on the policy agenda in the Northern Ireland context – notably Assessment for Learning (AfL). An emergent framework for assessing pupil rights, based on Article 12 of the United Nations Convention on the Rights of the Child (Lundy, 2007), is being used to explore the ways in which AfL classroom practice creates the conditions for increased pupil participation and consultation. Pupil views on their AfL classroom experiences and participation are explored by means of a variety of pupil-centred, creative research methods that engage and stimulate pupils to observe, communicate and analyse their learning and assessment experiences and give meaning to them. This presentation highlights preliminary data based on a sample of 11-14 years pupils' experiences of participation and consultation in classrooms adopting AfL pedagogical principles, and identifies characteristics that support or inhibit pupil participation in their learning and the expression of their views about such matters