Improved registration of DCE-MR images of the liver using a prior segmentation of the region of interest

In Dynamic Contrast-Enhanced MRI (DCE-MRI) of the liver, a series of images is acquired over a period of 20 minutes. Due to the patient's breathing, the liver is subject to a substantial displacement between acquisitions. Furthermore, due to its location in the abdomen, the liver also undergoes marked deformation. The large deformations...

A hybrid segmentation method for partitioning the liver based on 4D DCE-MR images

The Couinaud classification of hepatic anatomy partitions the liver into eight functionally independent segments. Detection and segmentation of the hepatic vein (HV), portal vein (PV) and inferior vena cava (IVC) plays an important role in the subsequent delineation of the liver segments. To facilitate pharmacokinetic modeling of the liver...

Perception and cognition of depth of field

A common way to present 3D materials to human observers nowadays is by stereoscopic displaying on 3D TVs or head-mounted displays such as the Oculus Rift. However, not everyone can see three-dimensional solid shape from stereoscopic viewing and the three-dimensional images remain two-dimensional pictures to them rather than solid shapes....

On Fine-grained Temporal Emotion Recognition in Video: How to Trade off Recognition Accuracy with Annotation Complexity?

Fine-grained emotion recognition is the process of automatically identifying the emotions of users at a fine granularity level, typically in the time intervals of 0.5s to 4s according to the expected duration of emotions. Previous work mainly focused on developing algorithms to recognize only one emotion for a video based on the user feedback...

Image analysis methods for dynamic hepatocyte-specific contrast enhanced MRI

Patients with colorectal cancer are frequently presented with liver metastases for which (partial) resection is often the best therapy. However, the future remnant liver, the remaining part of the liver after resection, should allow adequate liver function to avoid liver failure. This thesis presents novel methods for the accurate voxel-wise...

Visual discomfort and depth-of-field

Visual discomfort has been reported for certain visual stimuli and under particular viewing conditions, such as stereoscopic viewing. In stereoscopic viewing, visual discomfort can be caused by a conflict between accommodation and convergence cues that may specify different distances in depth. Earlier research has shown that depth-of-field,...

Human discrimination of depth of field in stereoscopic and nonstereoscopic photographs

Depth of field (DOF) is defined as the distance range within which objects are perceived as sharp. Previous research has focused on blur discrimination in artificial stimuli and natural photographs. The discrimination of DOF, however, has received less attention. Since DOF introduces blur which is related to distance in depth, many levels of...

Adaptation to climate change in coastal towns of between 10,000 and 50,000 inhabitants

This chapter focuses on mainland coastal towns that have populations of between 10,000 and 50,000 inhabitants. Through six case studies, the chapter develops an understanding of the characteristics that shape each of the communities. By exploring the climate change hazards each of the case studies are experiencing now and forecast into the...

Few-shot Learning for Fine-grained Emotion Recognition using Physiological Signals

Fine-grained emotion recognition can model the temporal dynamics of emotions, which is more precise than predicting one emotion retrospectively for an activity (e.g., video clip watching). Previous works require large amounts of continuously annotated data to train an accurate recognition model, however experiments to collect such large...

Corrnet: Fine-grained emotion recognition for video watching using wearable physiological sensors

Recognizing user emotions while they watch short-form videos anytime and anywhere is essential for facilitating video content customization and personalization. However, most works either classify a single emotion per video stimuli, or are restricted to static, desktop environments. To address this, we propose a correlation-based emotion...

Weakly-supervised Learning for Fine-grained Emotion Recognition using Physiological Signals

Instead of predicting just one emotion for one activity (e.g., video watching), fine-grained emotion recognition enables more temporally precise recognition. Previous works on fine-grained emotion recognition require segment-by-segment, fine-grained emotion labels to train the recognition algorithm. However, experiments to collect these...

CEAP-360VR: A Continuous Physiological and Behavioral Emotion Annotation Dataset for 360 VR Videos

Watching 360 videos using Virtual Reality (VR) head-mounted displays (HMDs) provides interactive and immersive experiences, where videos can evoke different emotions. Existing emotion self-report techniques within VR however are either retrospective or interrupt the immersive experience. To address this, we introduce the Continuous...

Comparison between dynamic gadoxetate-enhanced MRI and ^99m Tc-mebrofenin hepatobiliary scintigraphy with SPECT for quantitative assessment of liver function

Objectives: To compare Gd-EOB-DTPA dynamic hepatocyte-specific contrast-enhanced MRI (DHCE-MRI) with ^99m Tc-mebrofenin hepatobiliary scintigraphy (HBS) as quantitative liver function tests for the preoperative assessment of patients undergoing liver resection. Methods: Patients undergoing liver surgery and preoperative assessment...

A pharmacokinetic model including arrival time for two inputs and compensating for varying applied flip-angle in dynamic gadoxetic acid-enhanced MR imaging

Purpose Pharmacokinetic models facilitate assessment of properties of the micro-vascularization based on DCE-MRI data. However, accurate pharmacokinetic modeling in the liver is challenging since it has two vascular inputs and it is subject to large deformation and displacement due to respiration. Methods We propose an improved...

Change detection in pictorial and solid scenes: The role of depth of field

This paper investigates the influence of depth of field on change detection in both pictorial and solid scenes. In this work, a within-subjects experiment is conducted using a flicker paradigm, with which the hit rate and response time for change detection are obtained. The results show that depth of field has effects on change detection: the...

Wideband Hybrid-Class Power Amplifier for Base Station Applications Using LDMOS with Envelope Tracking System

Conventional RF power amplifiers are normally designed for peak efficiency at maximum output power. However, for WCDMA application, the power amplifier often operates at 6-8 dB power back-off. Consequently, when the power is backed-off from its peak point, the efficiency of conventional power amplifier drops sharply. The envelope elimination and...

Control of magnetic bearings in wind turbines

Direct drive generators applied to large wind turbines present some problems, such as very heavy and expensive price. The use of magnetic bearings has a possibility to reduce the weight of the direct drive generator. The control system for such magnetic bearings is considered. In the beginning, the thesis discusses the problems of direct drive...