Open X-Embodiment:Robotic learning datasets and RT-X models

Large, high-capacity models trained on diverse datasets have shown remarkable successes on efficiently tackling downstream applications. In domains from NLP to Computer Vision, this has led to a consolidation of pretrained models, with general pretrained backbones serving as a starting point for many applications. Can such a consolidation happen in robotics? Conventionally, robotic learning methods train a separate model for every application, every robot, and even every environment. Can we instead train "generalist" X-robot policy that can be adapted efficiently to new robots, tasks, and environments? In this paper, we provide datasets in standardized data formats and models to make it possible to explore this possibility in the context of robotic manipulation, alongside experimental results that provide an example of effective X-robot policies. We assemble a dataset from 22 different robots collected through a collaboration between 21 institutions, demonstrating 527 skills (160266 tasks). We show that a high-capacity model trained on this data, which we call RT-X, exhibits positive transfer and improves the capabilities of multiple robots by leveraging experience from other platforms. The project website is robotics-transformer-x.github.io

Molecular Dynamics Simulations of the Mechanical Properties of Cellulose Nanocrystals—Graphene Layered Nanocomposites

Cellulose nanocrystals (CNCs) have received a significant amount of attention due to their excellent physiochemical properties. Herein, based on bioinspired layered materials with excellent mechanical properties, a CNCs-graphene layered structure with covalent linkages (C-C bond) is constructed. The mechanical properties are systematically studied by molecular dynamics (MD) simulations in terms of the effects of temperature, strain rate and the covalent bond content. Compared to pristine CNCs, the mechanical performance of the CNCs-graphene layered structure has significantly improved. The elastic modulus of the layered structure decreases with the increase of temperature and increases with the increase of strain rate and covalent bond coverage. The results show that the covalent bonding and van der Waals force interactions at the interfaces play an important role in the interfacial adhesion and load transfer capacity of composite materials. These findings can be useful in further modeling of other graphene-based polymers at the atomic scale, which will be critical for their potential applications as functional materials

The Stability of Water Ejector Using in Heating System

AbstractIn the heating system, the water ejector can use the “surplus pressure” to pump return water from return pipe instead of using mixing pumps, thus achieving the purpose of energy conservation. The water ejector is normally devised in the design condition, however, it usually does not operate at the design point because the pressure and flow rate of water in water ejector varies with the fluctuation of adjacent heat consumer, which causes the deviation of the indoor air temperature from the designed value. In the present study, the allowed pressure fluctuation of water ejector was investigated under the condition that the indoor air temperature was maintained in a certain range. The experimental results showed that when indoor air temperature was set at °C, the allowed pressure fluctuation range for the water ejector in Harbin was -10%∼20%, and it expanded as the outdoor design temperature increased and/or the supply water temperature of primary network reduced

Liquid and solids separation for target resource recovery from thermal hydrolyzed sludge

This study proposed an integrated process for biogas generation and biochar production from thermal hydrolysis pretreated sludge (THP sludge). In this study, the liquid and solids fractions of THP sludge were separately processed for the first time. The liquid fraction of THP sludge (THP-L) reached the biodegradability (262.6 ± 5.1 mL CH₄/g tCODfₑₑd) on the 15th day during anaerobic treatment, while the solids fraction of THP sludge (THP-S) only contributed 31.0% to the total methane production and required more than 30 days digestion time. We investigated the feasibility to convert THP-S into biochar to realize the higher value of the solids fraction. The results prove the produced biochar can be used as slow-release fertilizer. Preliminary energy analysis was performed to evaluate the energy efficiency of the integrated approach, namely, methane generation from THP-L coupled with biochar production from THP-S. The process realized energy surplus of 0.81 MWh/tonne dry sludge. In addition, THP-L digested sludge showed better dewaterability, lower yield stress and reduced viscosity during digestion. The proposed new sludge treatment process therefore has lower operating cost and higher value returns.Nanyang Technological UniversityThe authors were grateful to the support of Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University

Elevation Regulates the Response of Climate Heterogeneity to Climate Change

Abstract Climate change represents a profound threat to the diversity and stability of global climate zones. However, the complex interplay between climate change and elevation in shaping climate heterogeneity is not yet fully understood. Here, we combine Shannon's diversity index (SHDI) with the Köppen‐Geiger climate classification to explore the altitudinal distributions of global climate heterogeneity; and their responses to climate change. The study reveals a distinctive pattern: SHDI, a proxy for climate heterogeneity tends to slow down or decline at lower elevations with increasing temperatures, while at higher elevations, it continues to rise due to continuing cold conditions. Examination of climate simulations, both with and without anthropogenic forcing, confirms that observed changes in climate heterogeneity are primarily attributable to anthropogenic climate change within these high‐elevation regions. This study underscores the importance of high‐elevation regions as not only custodians of diverse climate types but also potential refuges for species fleeing warmer climates

Contributions of Gene Modules Regulated by Essential Noncoding RNA in Colon Adenocarcinoma Progression

Noncoding RNAs (ncRNAs), especially microRNA (miRNA) and long noncoding RNA (lncRNA), have an impact on a variety of important biological processes during colon adenocarcinoma (COAD) progression. This includes chromatin organization, transcriptional and posttranscriptional regulation, and cell-cell signaling. The aim of this study is to identify the ncRNA-regulated modules that accompany the progression of COAD and to analyze their mechanisms, in order to screen the potential prognostic biomarkers for COAD. An integrative molecular analysis was carried out to identify the crosstalks of gene modules between different COAD stages, as well as the essential ncRNAs in the posttranscriptional regulation of these modules. 31 ncRNA regulatory modules were found to be significantly associated with overall survival in COAD patients. 17 out of the 31 modules (in which ncRNAs played essential roles) had improved the predictive ability for COAD patient survival compared to only the mRNAs of those modules, which were enriched in the core cancer hallmark pathways with closer interactions. These suggest that the ncRNAs’ regulatory modules not only exhibit close relation to COAD progression but also reflect the dynamic significant crosstalk of genes in the modules to the different malignant extent of COAD