85 research outputs found
City-level water withdrawal in China:Accounting methodology and applications
In the context of the freshwater crisis, accounting for water withdrawal could help planners better regulate water use in different sectors to combat water scarcity. However, the water withdrawal statistics in China are patchy, and the water data across all sectors at the city level appear to be relatively insufficient. Hence, we develop a general framework to, for the first time, estimate the water withdrawal of 58 economicâsocialâenvironmental sectors in cities in China. This methodology was applied because only inconsistent water statistics collected from different data sources at the city level are available. We applied it to 18 representative Chinese cities. Different from conventional perceptions that agriculture is usually the largest water user, industrial and household water withdrawal may also occupy the largest percentages in the water-use structure of some cities. The discrepancy among annual household water use per capita in the urban areas of different cities is relatively small (as is the case for rural areas), but that between urban and rural areas is large. As a result, increased attention should be paid to controlling industrial and urban household water use in particular cities. China should specifically prepare annual water accounts at the city level and establish a timetable to tackle water scarcity, which is a basic step toward efficient and sustainable water crisis mitigation
Gentopia: A Collaborative Platform for Tool-Augmented LLMs
Augmented Language Models (ALMs) empower large language models with the
ability to use tools, transforming them into intelligent agents for real-world
interactions. However, most existing frameworks for ALMs, to varying degrees,
are deficient in the following critical features: flexible customization,
collaborative democratization, and holistic evaluation. We present gentopia, an
ALM framework enabling flexible customization of agents through simple
configurations, seamlessly integrating various language models, task formats,
prompting modules, and plugins into a unified paradigm. Furthermore, we
establish gentpool, a public platform enabling the registration and sharing of
user-customized agents. Agents registered in gentpool are composable such that
they can be assembled together for agent collaboration, advancing the
democratization of artificial intelligence. To ensure high-quality agents,
gentbench, an integral component of gentpool, is designed to thoroughly
evaluate user-customized agents across diverse aspects such as safety,
robustness, efficiency, etc. We release gentopia on Github and will
continuously move forward
Upper bound of a band complex
Band structure for a crystal generally consists of connected components in
energy-momentum space, known as band complexes. Here, we explore a fundamental
aspect regarding the maximal number of bands that can be accommodated in a
single band complex. We show that in principle a band complex can have no
finite upper bound for certain space groups. It means infinitely many bands can
entangle together, forming a connected pattern stable against
symmetry-preserving perturbations. This is demonstrated by our developed
inductive construction procedure, through which a given band complex can always
be grown into a larger one by gluing a basic building block to it. As a
by-product, we demonstrate the existence of arbitrarily large accordion type
band structures containing bands, with .Comment: 6 pages, 4 figure
A pre-protection method for a pipe-jacking channel over shield tunnels
With the improvement of the planning level of underground space, the location of the planned under-crossing tunnel can be known in advance when constructing the upper-span tunnel. Therefore, pre-protection measures can be taken in advance during the construction of the upper-span tunnel. A new pre-protection method of a pipe-jacking channel was proposed to reduce the adverse effects of under-crossing shield tunnels. Numerical simulations of different pre-protection schemes were carried out using the finite element method to analyze its deformation control effect. The simulation results show that the deformation control effect of the gantry reinforcement scheme is the most significant. It is shown that the displacement of the pipe-jacking channel is more significantly suppressed with pre-protection measures than without preventive protection measures. The vertical displacement curve of the pipe-jacking channel exhibits a âWâ shape after the construction of the double-lane shield underpass. By comparing the three different working conditions, it is found that the maximum vertical displacement and surface settlement of the pipe-jacking channel greatly reduced the gantry reinforcement pre-protection. Compared with Case 3, the effect of the pre-protection measures adopted in Case 2 was less obvious, which indicated that the form of the pre-protection had an important influence on controlling the deformation of the pipe-jacking channel
An objective comparison of methods for augmented reality in laparoscopic liver resection by preoperative-to-intraoperative image fusion
Augmented reality for laparoscopic liver resection is a visualisation mode
that allows a surgeon to localise tumours and vessels embedded within the liver
by projecting them on top of a laparoscopic image. Preoperative 3D models
extracted from CT or MRI data are registered to the intraoperative laparoscopic
images during this process. In terms of 3D-2D fusion, most of the algorithms
make use of anatomical landmarks to guide registration. These landmarks include
the liver's inferior ridge, the falciform ligament, and the occluding contours.
They are usually marked by hand in both the laparoscopic image and the 3D
model, which is time-consuming and may contain errors if done by a
non-experienced user. Therefore, there is a need to automate this process so
that augmented reality can be used effectively in the operating room. We
present the Preoperative-to-Intraoperative Laparoscopic Fusion Challenge
(P2ILF), held during the Medical Imaging and Computer Assisted Interventions
(MICCAI 2022) conference, which investigates the possibilities of detecting
these landmarks automatically and using them in registration. The challenge was
divided into two tasks: 1) A 2D and 3D landmark detection task and 2) a 3D-2D
registration task. The teams were provided with training data consisting of 167
laparoscopic images and 9 preoperative 3D models from 9 patients, with the
corresponding 2D and 3D landmark annotations. A total of 6 teams from 4
countries participated, whose proposed methods were evaluated on 16 images and
two preoperative 3D models from two patients. All the teams proposed deep
learning-based methods for the 2D and 3D landmark segmentation tasks and
differentiable rendering-based methods for the registration task. Based on the
experimental outcomes, we propose three key hypotheses that determine current
limitations and future directions for research in this domain.Comment: 24 page
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