274 research outputs found
Energy saving potential of a counter-flow regenerative evaporative cooler for various climates of China: Experiment-based evaluation
© 2017 Recently there has been growing interest in regenerative evaporative coolers (REC), which can reduce the temperature of the supply air to below the wet-bulb of intake air and approach its dew-point. In this paper, we designed, fabricated and experimentally tested a counter-flow REC in laboratory. The REC's core heat and mass exchanger was fabricated using stacked sheets composed of high wicking evaporation (wickability of available materials was measured) and waterproof aluminium materials. The developed REC system has a much higher cooling performance compared to conventional indirect evaporative cooler. However, the decision to use the REC for China buildings depends on a dedicated evaluation of the net energy saved against the capital expended. Such an evaluation requires the hourly-based data on the availability of cooling capacity provided by the REC for various climates. The paper used an experiment-based method to estimate the cooling capacity and energy savings provided by the proposed REC for China's various climates. By using the experimental results and regional hourly-based weather data, the energy saving potential of the REC against an equivalent-sized mechanical air conditioner alone was analysed. The results indicate that, for all selected regions, the REC could reduce 53–100% of cooling load and 13–58% of electrical energy consumption annually
Patch-based 3D Natural Scene Generation from a Single Example
We target a 3D generative model for general natural scenes that are typically
unique and intricate. Lacking the necessary volumes of training data, along
with the difficulties of having ad hoc designs in presence of varying scene
characteristics, renders existing setups intractable. Inspired by classical
patch-based image models, we advocate for synthesizing 3D scenes at the patch
level, given a single example. At the core of this work lies important
algorithmic designs w.r.t the scene representation and generative patch
nearest-neighbor module, that address unique challenges arising from lifting
classical 2D patch-based framework to 3D generation. These design choices, on a
collective level, contribute to a robust, effective, and efficient model that
can generate high-quality general natural scenes with both realistic geometric
structure and visual appearance, in large quantities and varieties, as
demonstrated upon a variety of exemplar scenes.Comment: 23 pages, 26 figures, accepted by CVPR 2023. Project page:
http://weiyuli.xyz/Sin3DGen
Adaptive and Sequential Methods for Clinical Trials
This special issue describes state-of-the-art statistical research in adaptive and sequential methods and the application of such methods in clinical trials. It provides 1 review article and 5 research articles contributed by some of the leading experts in this field. The review article gives a comprehensive overview of the outstanding methodology in the current literature that is related to adaptive and sequential clinical trials, while each of the 5 research articles addresses specific critical issues in contemporary clinical trials, as summarized below
Towards a Neural Graphics Pipeline for Controllable Image Generation
In this paper, we leverage advances in neural networks towards forming a
neural rendering for controllable image generation, and thereby bypassing the
need for detailed modeling in conventional graphics pipeline. To this end, we
present Neural Graphics Pipeline (NGP), a hybrid generative model that brings
together neural and traditional image formation models. NGP decomposes the
image into a set of interpretable appearance feature maps, uncovering direct
control handles for controllable image generation. To form an image, NGP
generates coarse 3D models that are fed into neural rendering modules to
produce view-specific interpretable 2D maps, which are then composited into the
final output image using a traditional image formation model. Our approach
offers control over image generation by providing direct handles controlling
illumination and camera parameters, in addition to control over shape and
appearance variations. The key challenge is to learn these controls through
unsupervised training that links generated coarse 3D models with unpaired real
images via neural and traditional (e.g., Blinn- Phong) rendering functions,
without establishing an explicit correspondence between them. We demonstrate
the effectiveness of our approach on controllable image generation of
single-object scenes. We evaluate our hybrid modeling framework, compare with
neural-only generation methods (namely, DCGAN, LSGAN, WGAN-GP, VON, and SRNs),
report improvement in FID scores against real images, and demonstrate that NGP
supports direct controls common in traditional forward rendering. Code is
available at http://geometry.cs.ucl.ac.uk/projects/2021/ngp.Comment: Eurographics 202
Example-based Motion Synthesis via Generative Motion Matching
We present GenMM, a generative model that "mines" as many diverse motions as
possible from a single or few example sequences. In stark contrast to existing
data-driven methods, which typically require long offline training time, are
prone to visual artifacts, and tend to fail on large and complex skeletons,
GenMM inherits the training-free nature and the superior quality of the
well-known Motion Matching method. GenMM can synthesize a high-quality motion
within a fraction of a second, even with highly complex and large skeletal
structures. At the heart of our generative framework lies the generative motion
matching module, which utilizes the bidirectional visual similarity as a
generative cost function to motion matching, and operates in a multi-stage
framework to progressively refine a random guess using exemplar motion matches.
In addition to diverse motion generation, we show the versatility of our
generative framework by extending it to a number of scenarios that are not
possible with motion matching alone, including motion completion, key
frame-guided generation, infinite looping, and motion reassembly. Code and data
for this paper are at https://wyysf-98.github.io/GenMM/Comment: SIGGRAPH 2023. Project page: https://wyysf-98.github.io/GenMM/,
Video: https://www.youtube.com/watch?v=lehnxcade4
MoCo-Flow: Neural Motion Consensus Flow for Dynamic Humans in Stationary Monocular Cameras
Synthesizing novel views of dynamic humans from stationary monocular cameras
is a popular scenario. This is particularly attractive as it does not require
static scenes, controlled environments, or specialized hardware. In contrast to
techniques that exploit multi-view observations to constrain the modeling,
given a single fixed viewpoint only, the problem of modeling the dynamic scene
is significantly more under-constrained and ill-posed. In this paper, we
introduce Neural Motion Consensus Flow (MoCo-Flow), a representation that
models the dynamic scene using a 4D continuous time-variant function. The
proposed representation is learned by an optimization which models a dynamic
scene that minimizes the error of rendering all observation images. At the
heart of our work lies a novel optimization formulation, which is constrained
by a motion consensus regularization on the motion flow. We extensively
evaluate MoCo-Flow on several datasets that contain human motions of varying
complexity, and compare, both qualitatively and quantitatively, to several
baseline methods and variants of our methods. Pretrained model, code, and data
will be released for research purposes upon paper acceptance
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