Smartphone picture organization: a hierarchical approach

We live in a society where the large majority of the population has a camera-equipped smartphone. In addition, hard drives and cloud storage are getting cheaper and cheaper, leading to a tremendous growth in stored personal photos. Unlike photo collections captured by a digital camera, which typically are pre-processed by the user who organizes them into event-related folders, smartphone pictures are automatically stored in the cloud. As a consequence, photo collections captured by a smartphone are highly unstructured and because smartphones are ubiquitous, they present a larger variability compared to pictures captured by a digital camera. To solve the need of organizing large smartphone photo collections automatically, we propose here a new methodology for hierarchical photo organization into topics and topic-related categories. Our approach successfully estimates latent topics in the pictures by applying probabilistic Latent Semantic Analysis, and automatically assigns a name to each topic by relying on a lexical database. Topic-related categories are then estimated by using a set of topic-specific Convolutional Neuronal Networks. To validate our approach, we ensemble and make public a large dataset of more than 8,000 smartphone pictures from 40 persons. Experimental results demonstrate major user satisfaction with respect to state of the art solutions in terms of organization.Peer ReviewedPreprin

Using Learning Management Systems to Support Students' Collaborative Learning in Higher Education

Learning Management Systems (LMS) are web-based systems for the distribution, management and retrieval of course materials, and to support communication between students and instructors. A LMS can also support peer collaboration by providing students with the capacity to create their own project sites. In this paper we present data from system logs, surveys, and interviews to investigate how one such system, CTools, is used by students at a large public university to facilitate peer learning.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108483/1/CSCL_2007_Project_Sites.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/108483/2/CSCL_2007_Project_Sites_Poster.pdfDescription of CSCL_2007_Project_Sites.pdf : Main articleDescription of CSCL_2007_Project_Sites_Poster.pdf : Poster Fil

What Happens to the Scores? The Effects of Learning Management Systems Use on Students' Course Evaluations

Learning Management Systems (LMS) are web-based systems that allow instructors and/or students to share materials, submit and return assignments, and communicate online. In this study, we explored the possible effects of LMS use on students' assessments of courses, instructor effectiveness, and their own learning. We examined the relationship between instructors' LMS use over two academic terms and three items from students’ course evaluations, and used the results from a user survey to inform our understanding of the relationship between course ratings and LMS use. Findings suggest that students do not rate courses more highly when instructors use LMSs. However, survey data shows that students value LMSs but perhaps for reasons different from instructors’. As instructors gain experience with tools within LMSs that foster interaction outside the classroom, their use of these systems may lead to improvements in course evaluation scores.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108482/1/AERA_2007_Eval_Paper.pd

Scaffolds: Experimenting with student­-driven digital badging in an iSchool context

Digital badge systems can be contentious to start and challenging to implement. In this project, we examine the development of an open, student-­led, peer-­to-­peer badging framework within an iSchool context. Scaffolds is a dynamic set of digital badges created to give students more concrete guidance in their exploration of the field of information science. The badges provide a way for students to customize their exploration of co­-curricular materials and activities to augment their educational experience. Using motivation and perception surveys, as well as in­-depth interviews with participants, the goal of this research is to understand what motivates students to participate in digital badges programs and how an open badging platform can be used to encourage student engagement in co-­curricular educational activities.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110790/2/walker_lee_lonn_scaffolds_iConference2015Submission.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/110790/3/walker_lee_lonn_scaffolds_iConference2015Poster.pdfDescription of walker_lee_lonn_scaffolds_iConference2015Submission.pdf : Conference Paper SubmissionDescription of walker_lee_lonn_scaffolds_iConference2015Poster.pdf : Conference Poste

Customized course advising: investigating engineering student success with incoming profiles and patterns of concurrent course enrollment

Every college student registers for courses from a catalog of numerous offerings each term. Selecting the courses in which to enroll, and in what combinations, can dramatically impact each student's chances for academic success. Taking inspiration from the STEM Academy, we wanted to identify the characteristics of engineering students who graduate with 3.0 or above grade point average. The overall goal of the Customized Course Advising project is to determine the optimal term-by-term course selections for all engineering students based on their incoming characteristics and previous course history and performance, paying particular attention to concurrent enrollment. We found that ACT Math, SAT Math, and Advanced Placement exam can be effective measures to measure the students' academic preparation level. Also, we found that some concurrent course-enrollment patterns are highly predictive of first-term and overall academic success.http://deepblue.lib.umich.edu/bitstream/2027.42/110782/1/Customized Course Advising Investigating Engineering Student Success with Incoming Profiles and Patterns of Concurrent Course Enrollment.pdfDescription of Customized Course Advising Investigating Engineering Student Success with Incoming Profiles and Patterns of Concurrent Course Enrollment.pdf : Proceeding pd

The political ecology of Chinese large dams in Cambodia: implications, challenges and lessons learnt from the Kamchay Dam

Given the opportunities offered by foreign investment in energy infrastructure mostly by Chinese firms, the Government of Cambodia is giving high priority to developing hydropower resources for reducing energy poverty and powering economic growth. Using a "Political ecology of the Asian drivers" framework, this paper assesses China's involvement in the development of large dams' in Cambodia and its impacts on the access of natural resources such as water and energy by dam builders, local communities and the government. This analysis is based on 61 interviews and 10 focus group discussions with affected communities, institutional actors, Chinese dam builders and financiers in relation to the first large Chinese dam built in Cambodia: the Kamchay dam. Based on the results of the analysis this paper makes recommendations on how to improve the planning, implementation and governance of future large dams in Cambodia

PET attenuation coefficients from CT images: experimental evaluation of the transformation of CT into PET 511-keV attenuation coefficients

The CT data acquired in combined PET/CT studies provide a fast and essentially noiseless source for the correction of photon attenuation in PET emission data. To this end, the CT values relating to attenuation of photons in the range of 40-140keV must be transformed into linear attenuation coefficients at the PET energy of 511keV. As attenuation depends on photon energy and the absorbing material, an accurate theoretical relation cannot be devised. The transformation implemented in the Discovery LS PET/CT scanner (GE Medical Systems, Milwaukee, Wis.) uses a bilinear function based on the attenuation of water and cortical bone at the CT and PET energies. The purpose of this study was to compare this transformation with experimental CT values and corresponding PET attenuation coefficients. In 14 patients, quantitative PET attenuation maps were calculated from germanium-68 transmission scans, and resolution-matched CT images were generated. A total of 114 volumes of interest were defined and the average PET attenuation coefficients and CT values measured. From the CT values the predicted PET attenuation coefficients were calculated using the bilinear transformation. When the transformation was based on the narrow-beam attenuation coefficient of water at 511keV (0.096cm-1), the predicted attenuation coefficients were higher in soft tissue than the measured values. This bias was reduced by replacing 0.096cm-1 in the transformation by the linear attenuation coefficient of 0.093cm-1 obtained from germanium-68 transmission scans. An analysis of the corrected emission activities shows that the resulting transformation is essentially equivalent to the transmission-based attenuation correction for human tissue. For non-human material, however, it may assign inaccurate attenuation coefficients which will also affect the correction in neighbouring tissu

Metformin for non-diabetic patients with coronary heart disease (the CAMERA study): a randomised controlled trial

<br>Background: Metformin reduces cardiovascular risk in patients with type 2 diabetes seemingly independent of lowering blood glucose concentration. We assessed the cardiovascular effects of metformin in individuals without type 2 diabetes.</br> <br>Methods: We did a single-centre, double-blind, placebo-controlled trial at the Glasgow Clinical Research Facility (Glasgow, UK). We enrolled patients taking statins who did not have type 2 diabetes but who did have coronary heart disease and large waist circumferences. Participants were randomly assigned (1:1) by computer to either metformin (850 mg twice daily) or matching placebo in block sizes of four. Patients, investigators, trial staff, and statisticians were masked to treatment allocation. The primary endpoint was progression of mean distal carotid intima-media thickness (cIMT) over 18 months in the modified intention-to-treat population. Secondary endpoints were changes in carotid plaque score (in six regions), measures of glycaemia (HbA1c, fasting glucose, and insulin concentrations, and Homeostasis Model Assessment of Insulin Resistance [HOMA-IR]), and concentrations of lipids, high sensitivity C-reactive protein, and tissue plasminogen activator. The trial was registered at ClinicalTrials.gov, number NCT00723307.</br> <br>Findings: We screened 356 patients, of whom we enrolled 173 (86 in the metformin group, 87 in the placebo group). Average age was 63 years. At baseline, mean cIMT was 0·717 mm (SD 0·129) and mean carotid plaque score was 2·43 (SD 1·55). cIMT progression did not differ significantly between groups (slope difference 0·007 mm per year, 95% CI −0·006 to 0·020; p=0·29). Change of carotid plaque score did not differ significantly between groups (0·01 per year, 95% CI −0·23 to 0·26; p=0·92). Patients taking metformin had lower HbA1c, insulin, HOMA-IR, and tissue plasminogen activator compared with those taking placebo, but there were no significant differences for total cholesterol, HDL-cholesterol, non-HDL-cholesterol, triglycerides, high sensitivity C-reactive protein, or fasting glucose. 138 adverse events occurred in 64 patients in the metformin group versus 120 in 60 patients in the placebo group. Diarrhoea and nausea or vomiting were more common in the metformin group than in the placebo group (28 vs 5).</br> <br>Interpretation: Metformin had no effect on cIMT and little or no effect on several surrogate markers of cardiovascular disease in non-diabetic patients with high cardiovascular risk, taking statins. Further evidence is needed before metformin can be recommended for cardiovascular benefit in this population.</br&gt

Duration of chronic heart failure affects outcomes with preserved effects of heart rate reduction with ivabradine: findings from SHIFT

Aims: In heart failure (HF) with reduced ejection fraction and sinus rhythm, heart rate reduction with ivabradine reduces the composite incidence of cardiovascular death and HF hospitalization. Methods and results: It is unclear whether the duration of HF prior to therapy independently affects outcomes and whether it modifies the effect of heart rate reduction. In SHIFT, 6505 patients with chronic HF (left ventricular ejection fraction of ≤35%), in sinus rhythm, heart rate of ≥70 b.p.m., treated with guideline-recommended therapies, were randomized to placebo or ivabradine. Outcomes and the treatment effect of ivabradine in patients with different durations of HF were examined. Prior to randomization, 1416 ivabradine and 1459 placebo patients had HF duration of ≥4 weeks and <1.5 years; 836 ivabradine and 806 placebo patients had HF duration of 1.5 years to <4 years, and 989 ivabradine and 999 placebo patients had HF duration of ≥4 years. Patients with longer duration of HF were older (62.5 years vs. 59.0 years; P < 0.0001), had more severe disease (New York Heart Association classes III/IV in 56% vs. 44.9%; P < 0.0001) and greater incidences of co-morbidities [myocardial infarction: 62.9% vs. 49.4% (P < 0.0001); renal dysfunction: 31.5% vs. 21.5% (P < 0.0001); peripheral artery disease: 7.0% vs. 4.8% (P < 0.0001)] compared with patients with a more recent diagnosis. After adjustments, longer HF duration was independently associated with poorer outcome. Effects of ivabradine were independent of HF duration. Conclusions: Duration of HF predicts outcome independently of risk indicators such as higher age, greater severity and more co-morbidities. Heart rate reduction with ivabradine improved outcomes independently of HF duration. Thus, HF treatments should be initiated early and it is important to characterize HF populations according to the chronicity of HF in future trials