| 1. |
- Engelke, Ulrich, et al.
(författare)
-
Comparative Study of Fixation Density Maps
- 2013
-
Ingår i: IEEE Transactions on Image Processing. - : IEEE. - 1057-7149 .- 1941-0042. ; 22:3, s. 1121-1133
-
Tidskriftsartikel (refereegranskat)abstract
- Fixation density maps (FDM) created from eye tracking experiments are widely used in image processing applications. The FDM are assumed to be reliable ground truths of human visual attention and as such, one expects a high similarity between FDM created in different laboratories. So far, no studies have analyzed the degree of similarity between FDM from independent laboratories and the related impact on the applications. In this paper, we perform a thorough comparison of FDM from three independently conducted eye tracking experiments. We focus on the effect of presentation time and image content and evaluate the impact of the FDM differences on three applications: visual saliency modeling, image quality assessment, and image retargeting. It is shown that the FDM are very similar and that their impact on the applications is low. The individual experiment comparisons, however, are found to be significantly different, showing that inter-laboratory differences strongly depend on the experimental conditions of the laboratories. The FDM are publicly available to the research community.
|
|
| 2. |
- Ji, Chenlin, et al.
(författare)
-
Postnatal overfeeding promotes early onset and exaggeration of high-fat diet-induced nonalcoholic fatty liver disease through disordered hepatic lipid metabolism in rats
- 2014
-
Ingår i: Journal of Nutritional Biochemistry. - : Elsevier. - 0955-2863 .- 1873-4847. ; 25:11, s. 1108-1116
-
Tidskriftsartikel (refereegranskat)abstract
- Exposure to overnutrition in critical or sensitive developmental periods may increase the risk of developing obesity and metabolic syndrome in adults. Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome, but the relationship among postnatal nutrition, lipid metabolism, and NAFLD progression during development remains poorly understood. Here we investigated in a rat model whether postnatal overfeeding increases susceptibility to NAFLD in response to a high-fat diet. Litters from Sprague-Dawley dams were culled to three (small litters) or ten (normal litters) pups and then weaned onto a standard or high-fat diet at postnatal day 21 to generate normal-litter, small-litter, normal-litter/high-fat, and small-litter/high-fat groups. At age 16 weeks, the small-litter and both high-fat groups showed obesity, dyslipidemia, and insulin resistance. Hepatic disorders appeared earlier in the small-litter/high-fat rats with greater liver mass gain and higher hepatic triglycerides and steatosis score versus normal-litter/high-fat rats. Hepatic acetyl-CoA carboxylase activity and mRNA expression were increased in small-litter rats and aggravated in small-litter/high-fat rats but not in normal-litter/high-fat rats. The high expression in small-litter/high-fat rats coincided with high sterol regulatory element-binding protein-1c mRNA and protein expression. However, mRNA expression of enzymes involved in hepatic fatty acid oxidation (carnitine palmitoyltransferase 1) and output (microsomal triglyceride transfer protein) was decreased under a high-fat diet regardless of litter size. In conclusion, overfeeding related to small-litter rearing during lactation contributes to the NAFLD phenotype when combined with a high-fat diet, possibly through up-regulated hepatic lipogenesis. (C) 2014 Elsevier Inc. All rights reserved.
|
|
| 3. |
- Wang, Helin, et al.
(författare)
-
Efficient Naphthalene Imide-Based Interface Engineering Materials for Enhancing Perovskite Photovoltaic Performance and Stability
- 2020
-
Ingår i: ACS Applied Materials and Interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 12:37, s. 42348-42356
-
Tidskriftsartikel (refereegranskat)abstract
- The ways to overcome surface charge recombination and poor interface contact are still the central challenges for the development of inorganic-organic hybrid halide perovskite solar cells (PSCs). [6,6]-Phenyl C-61 butyric acid methyl ester (PCBM) is commonly employed in PSCs, but it has some disadvantages including high charge recombination and poor surface coverage. Therefore, the addition of an interfacial engineering layer showing efficient surface passivation, electron extraction, and excellent interface contact can solve the above problems. Furthermore, by employing interface engineering with a spike structure of the energy levels, the reduced energy losses are beneficial to elevating the open-circuit voltage (V-oc) in PSCs. Herein, the linear naphthalene imide dimer containing an indacenodithiophene unit (IDTT2NPI) has been developed as an excellent interface engineering material to strengthen the perovskite performance. The introduction of a spike interface on the top of a methylammonium lead triiodide (MAPbI(3)) film resulted in a high V-oc of 1.12 V with the optimal efficiency reaching 20.2%. The efficiency enhancement can be traced to the efficient surface passivation and enhanced interface contact. The mechanism of IDTT2NPI as the interface engineering layer was investigated by both experiments and theoretical calculations. This work provides a promising naphthalene imide-based interfacial material for high-efficiency and stable PSCs.
|
|
| 4. |
- Wang, Junle, et al.
(författare)
-
Quantifying depth bias in free viewing of still stereoscopic synthetic stimuli
- 2011
-
Ingår i: Abstracts of the 16th European Conference on Eye Movements. ; , s. 92-
-
Konferensbidrag (refereegranskat)abstract
- In studies of 2D visual attention, eye-tracking data show a so-called “center-bias”, which means that fixationsare biased towards the center of 2D still images. However, in stereoscopic visual attention, depth is anotherfeature having great influence on guiding eye movements. Relatively little is known about the impact of depth.Several studies mentioned that people tend to look at the objects at certain depth planes. Therefore, it isreasonable to suppose the existence of a “depth-bias”. But studies proving or quantifying this depth-bias arestill limited. We conducted a binocular eye-tracking experiment by showing synthetic stimuli on a stereoscopicdisplay. Observers were required to do a free-viewing task through active shutter glasses. Gaze positions ofboth eyes were recorded for obtaining the depth of fixation. Stimuli were well designed in order to let thecenter-bias and depth-bias affect eye movements individually. Results showed that the number of fixationsvaried as a function of depth planes. There was also a relationship between the duration of fixation and thedepth plane where the objects were located.
|
|
| 5. |
- Wang, Junle, et al.
(författare)
-
Study of depth bias of observers in free viewing of still stereoscopic synthetic stimuli
- 2012
-
Ingår i: JOURNAL OF EYE MOVEMENT RESEARCH. - : University of Bern. - 1995-8692. ; 5:5, s. Art. no. 1-
-
Tidskriftsartikel (refereegranskat)abstract
- Observers' fixations exhibit a marked bias towards certain areas on the screen when viewing scenes on computer monitors. For instance, there exists a well-known "center-bias" which means that fixations are biased towards the center of the screen during the viewing of 2D still images. In the viewing of 3D content, stereoscopic displays enhance depth perception by the mean of binocular parallax. This additional depth cue has a great influence on guiding eye movements. Relatively little is known about the impact of binocular parallax on visual attention of the 3D content displayed on stereoscopic screen. Several studies mentioned that people tend to look preferably at the objects located at certain positions in depth. But studies proving or quantifying this depth-bias are still limited. In this paper, we conducted a binocular eye-tracking experiment by showing synthetic stimuli on a stereoscopic display. Observers were required to do a free-viewing task through passive polarized glasses. Gaze positions of both eyes were recorded and the depth of eyes' fixation was determined. The stimuli used in the experiment were designed in such a way that the center-bias and the depth-bias affect eye movements individually. Results indicate the existence of a depth-bias: objects closer to the viewer attract attention earlier than distant objects, and the number of fixations located on objects varies as a function of objects' depth. The closest object in a scene always attracts most fixations. The fixation distribution along depth also shows a convergent behavior as the viewing time increases.
|
|
