61 research outputs found
Dynamic Control for Batch Process Systems Using Stochastic Utility Evaluation
Most research studies in the batch process control problem are focused on optimizing system performance. The methods address the problem by minimizing single criterion such as cycle time and tardiness, or bi-criteria such as cycle time and tardiness, and earliness and tardiness. This research demonstrates the use of Stochastic Utility Evaluation (SUE) function approach to optimize system performance using multiple criteria.
In long production cycles, the earliness and tardiness weight (utility) of products vary depending on the time. As the time approaches the due-date, it affects contractual penalties, loss of customer goodwill and the storage period for the completed products. It is necessary to reflect the weight of products for earliness and tardiness at decision epochs to decide on the optimal strategy. This research explores how stochastic utility function using stochastic information can be derived and used to strategically improve existing approaches for the batch process control problem.
This research first explores how SUE function can be applied to existing model for bi-objective problem such as cycle time and tardiness. Benchmark strategies using SUE function (NACH-SUE, MBS-SUE, No idle and full batch) are compared to each other. The experimental results show that NACH-SUE effectively improves mean cycle time and tardiness performance respectively than other benchmark strategies.
Next, SUE function for earliness and tardiness is used in an existing model to develop a tri-objective problem. Typically, this problem is very complex to solve due to its trade-off relationship. However SUE function makes it relatively easy to solve the tri-objective problem since SUE function can be incorporated in an existing model. It is observed that SUE function can be effectively used for solving a tri-objective problem. Performance improvement for averaged value of cycle time, earliness and tardiness is observed under a comprehensive set of experimental conditions
StRDAN: Synthetic-to-Real Domain Adaptation Network for Vehicle Re-Identification
Vehicle re-identification aims to obtain the same vehicles from vehicle
images. This is challenging but essential for analyzing and predicting traffic
flow in the city. Although deep learning methods have achieved enormous
progress for this task, their large data requirement is a critical shortcoming.
Therefore, we propose a synthetic-to-real domain adaptation network (StRDAN)
framework, which can be trained with inexpensive large-scale synthetic and real
data to improve performance. The StRDAN training method combines domain
adaptation and semi-supervised learning methods and their associated losses.
StRDAN offers significant improvement over the baseline model, which can only
be trained using real data, for VeRi and CityFlow-ReID datasets, achieving 3.1%
and 12.9% improved mean average precision, respectively.Comment: 7 pages, 2 figures, CVPR Workshop Paper (Revised
Learning to Estimate Robust 3D Human Mesh from In-the-Wild Crowded Scenes
We consider the problem of recovering a single person's 3D human mesh from
in-the-wild crowded scenes. While much progress has been in 3D human mesh
estimation, existing methods struggle when test input has crowded scenes. The
first reason for the failure is a domain gap between training and testing data.
A motion capture dataset, which provides accurate 3D labels for training, lacks
crowd data and impedes a network from learning crowded scene-robust image
features of a target person. The second reason is a feature processing that
spatially averages the feature map of a localized bounding box containing
multiple people. Averaging the whole feature map makes a target person's
feature indistinguishable from others. We present 3DCrowdNet that firstly
explicitly targets in-the-wild crowded scenes and estimates a robust 3D human
mesh by addressing the above issues. First, we leverage 2D human pose
estimation that does not require a motion capture dataset with 3D labels for
training and does not suffer from the domain gap. Second, we propose a
joint-based regressor that distinguishes a target person's feature from others.
Our joint-based regressor preserves the spatial activation of a target by
sampling features from the target's joint locations and regresses human model
parameters. As a result, 3DCrowdNet learns target-focused features and
effectively excludes the irrelevant features of nearby persons. We conduct
experiments on various benchmarks and prove the robustness of 3DCrowdNet to the
in-the-wild crowded scenes both quantitatively and qualitatively. The code is
available at https://github.com/hongsukchoi/3DCrowdNet_RELEASE.Comment: Accepted to CVPR 2022, 16 pages including the supplementary materia
HandNeRF: Learning to Reconstruct Hand-Object Interaction Scene from a Single RGB Image
This paper presents a method to learn hand-object interaction prior for
reconstructing a 3D hand-object scene from a single RGB image. The inference as
well as training-data generation for 3D hand-object scene reconstruction is
challenging due to the depth ambiguity of a single image and occlusions by the
hand and object. We turn this challenge into an opportunity by utilizing the
hand shape to constrain the possible relative configuration of the hand and
object geometry. We design a generalizable implicit function, HandNeRF, that
explicitly encodes the correlation of the 3D hand shape features and 2D object
features to predict the hand and object scene geometry. With experiments on
real-world datasets, we show that HandNeRF is able to reconstruct hand-object
scenes of novel grasp configurations more accurately than comparable methods.
Moreover, we demonstrate that object reconstruction from HandNeRF ensures more
accurate execution of a downstream task, such as grasping for robotic
hand-over.Comment: 9 pages, 4 tables, 7 figure
PexRAP inhibits PRDM16-mediated thermogenic gene expression
How the nuclear receptor PPARĪ³ regulates the development of two functionally distinct types of adipose tissue, brown and white fat, as well as the browning of white fat, remains unclear. Our previous studies suggest that PexRAP, a peroxisomal lipid synthetic enzyme, regulates PPARĪ³ signaling and white adipogenesis. Here, we show that PexRAP is an inhibitor of brown adipocyte gene expression. PexRAP inactivation promoted adipocyte browning,Ā increased energy expenditure, and decreased adiposity. Identification of PexRAP-interacting proteins suggests that PexRAP function extends beyond its role as a lipid synthetic enzyme. Notably, PexRAP interacts with importin-Ī²1, a nuclear import factor, and knockdown of PexRAP in adipocytes reduced the levels of nuclear phospholipids. PexRAP also interacts with PPARĪ³, as well as PRDM16, a critical transcriptional regulator of thermogenesis, and disrupts the PRDM16-PPARĪ³ complex, providing a potential mechanism for PexRAP-mediated inhibition of adipocyte browning. These results identify PexRAP as an important regulator of adipose tissue remodeling
Electroluminescence in polymer-fullerene photovoltaic cells
We report electroluminescence (EL) in photovoltaic (PV) cells based on semiconducting polymer-fullerene composites. By applying a forward bias to the PV cells, the devices exhibited a clear EL action with a peak around 1.5 eV. We ascribe this peak to an "electric field-assisted exciplex" formed between the electrons in the fullerenes and the holes in the polymers, thereby resulting in radiative recombination in the composites. This finding is totally unexpected because of a strong photoluminescence quenching in the same materials. Since the same devices also showed typical photovoltaic effects under illumination, our results demonstrate a dual functionality in one device; polymer photovoltaic cells and polymer light-emitting diodes.open464
New solvation free energy function comprising intermolecular solvation and intramolecular self-solvation terms
Abstract Solvation free energy is a fundamental thermodynamic quantity that should be determined to estimate various physicochemical properties of a molecule and the desolvation cost for its binding to macromolecular receptors. Here, we propose a new solvation free energy function through the improvement of the solvent-contact model, and test its applicability in estimating the solvation free energies of organic molecules with varying sizes and shapes. This new solvation free energy function is constructed by combining the existing solute-solvent interaction term with the self-solvation term that reflects the effects of intramolecular interactions on solvation. Four kinds of atomic parameters should be determined in this solvation model: atomic fragmental volume, maximum atomic occupancy, atomic solvation, and atomic self-solvation parameters. All of these parameters for total 37 atom types are optimized by the operation of a standard genetic algorithm in such a way to minimize the difference between the experimental solvation free energies and those calculated by the solvation free energy function for 362 organic molecules. The solvation free energies estimated from the new solvation model compare well with the experimental results with the associated squared correlation coefficients of 0.88 and 0.85 for training and test sets, respectively. The present solvation model is thus expected to be useful for estimating the solvation free energies of organic molecules.</p
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