Accurate and timely mapping of flood extent plays a crucial role in disaster management such as damage assessment and relief activities. In recent years, high-resolution optical imagery becomes increasingly available with the wide deployment of satellites and drones. However, analyzing such imagery data to extract flood extent poses unique challenges due to noises such as obstacles (e.g., tree canopies, clouds). In this paper, we propose an elevation-guided annotation tool for flood extent mapping, which allows annotators to provide the flooded/dry labels for just a few pixels to cover a large area where the labels of most other pixels are automatically inferred. The physical rule we use here to guide the automatic label inference is that if a location is flooded (resp. dry), then its adjacent locations with a lower (resp. higher) elevation must also be flooded (resp. dry). In this way, annotators just need to label the pixels that they are confident with, and the true labels of many ambiguous pixels such as tree-canopy ones can be automatically inferred. We demonstrate the usage of our annotation tool using high-resolution aerial imagery from National Oceanic and Atmospheric Administration (NOAA) National Geodetic Survey (NGS) together with the corresponding Digital Elevation Model (DEM) data. The annotated data can be used to train machine learning models for flood extent mapping, and we train U-Net models to infer the flood map for an unseen region and achieve a high accuracy. Our annotation tool is open-sourced at https://github.com/SaugatAdhikari/Flood-Annotation-Tool.

iPSCs are pluripotent stem cells generated from adult tissue through a process called cellular reprogramming. However, cellular reprogramming is a lengthy and inefficient process since only a small fraction of cells can reliably become iPSCs. The reprogramming efficiency is generally measured by counting the number of reprogrammed colonies that emerge and grow as rounded clusters of compact cells around 20 days after adding the reprogramming vectors. However, counting colonies manually is labor-intensive, time-consuming, and error-prone.This work develops a semi-automated tool for colony counting from iPSC culture plate images, where colonies are automatically annotated with their centers. Our model uses multi-task learning to jointly predict the colony centers and conduct colony segmentation, in hope that the latter will improve the performance of the former. An annotation tool is developed to facilitate the collection of ground-truth masks by crowdsourcing. Two center-based loss functions are investigated and compared, one based on oriented Gaussian kernel and the other based on average Hausdorff distance. Extensive experiments verify that (i) the former loss outperforms the latter, (ii) the segmentation head is effective in improving center predictions. Our code has been released at https://github.com/MTSami/iPSC-Colony-Counting.

Fast diagnostic prediction of brain dysfunctions such as autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD) and Alzheimer’s disease is important due to their prevalence in the population. A typical workflow for brain dysfunction prediction is to preprocess a brain image into a network of connected brain regions, where indicative features are extracted using simple linear or convolutional models to be used for prediction. However, due to restrictions on patient data sharing such as HIPAA rules, the number of training samples is often very limited. Even with efforts like the ABIDE initiative that aggregated brain imaging data from laboratories around the world, the subject number merely reaches around 1,000, limiting the effectiveness of data-driven models such as deep learning models.To overcome this data scarcity problem, we propose a GAN-based data augmentation technique to generate realistic brain region networks, which are used to increase the size of an existing training set so that a brain dysfunction classifier can be better trained to achieve a higher prediction accuracy. In the brain region network setting, we propose a generator that considers each brain region as an embedding, so that the connectivity between two regions can be computed using the inner product of their embeddings. This generator is trained along with a phenotype-enhanced BrainNetCNN, a domain-specific discriminator (i.e., classifier), to improve its prediction accuracy. Our embedding-based generator generates samples following the original data feature distribution (i.e., age, gender, and health condition), which improves generator quality and avoids mode collapse.Our design is generally applicable to various neuroimaging data, and experimental results obtained on two real datasets ABIDE-I and ADHD200 confirmed the effectiveness of the proposed method. Our model has been open-sourced on GitHub at https://github.com/binwsh/GAN-for-Neural-Graph.

Micromobility refers to small, lightweight vehicles such as shared bicycles and electric scooters (e-scooters). Recently, shared micromobility services see increasing deployment in urban areas to solve the "last mile´ problem, where the travel distance is considered long when walking on foot, but not worth driving a car (e.g., to avoid parking). A key question to ask when deciding whether to deploy a shared micromobility service in an area is: how much car traffic can be reduced during peak hours if this service is deployed? This work answers this question by agent-based transportation simulation. The key challenge here is to generate a realistic synthetic population of the target area along with their travel day-plans. We propose to use an area-specific travel survey plus openly available data sources for this purpose, and demonstrate our approach through a case study that studied the traffic impacts of deploying dockless e-scooters in Birmingham, AL. A demo of our simulation is available at https://youtu.be/zh_mHQ6ck4U.

Micromobility refers to small, lightweight vehicles such as shared bicycles and electric scooters (e-scooters). Recently, shared micromobility services see increasing deployment in urban areas, especially for trips where the travel distance is considered long for walking, but not worth driving a car (e.g., to avoid parking). A key question to ask when deciding whether to deploy a shared micromobility service in an area is: how much car traffic can be reduced during peak hours if this service is deployed? This work answers this question by agent-based transportation simulation. The key contribution is to generate a realistic synthetic population of transportation users in the target area along with their travel day-plans, using an area-specific travel survey plus openly available data sources. We demonstrate our approach through a case study on the deployment of dockless e-scooters in Birmingham, AL, with a demo at https://youtu.be/zh_mHQ6ck4U.

Various industries use towers as part of their daily operations, such as transmission towers (aka. electricity pylons), telecommunications towers and water towers. These towers re- quire regular maintenance, and before the maintenance work can be done, a preliminary survey must be conducted to determine where to work. More and more, such surveys are being conducted via drones. This work develops a detection model to help locate tower issues from the video frames of drones. However, it does not provide satisfactory performance to directly train such an object detection model with the annotated problem locations from domain experts. Therefore, we propose to improve the quality of the extracted image features with the help of another separate task which detects the various parts that are involved in the tower issues, such as bolts, nuts, washers and pins, the annotations of which can be done without the need of domain expertise. Through this multi-task learning scheme, we improved the problem detection recall from 59.6% to 71.5%, providing much more effective recommendations of potential issues for inspectors to examine further. Also, the average number of problem detections in each image is merely 5.54 so inspectors are not overwhelmed by the recommended locations.