MO-VLN: A Multi-Task Benchmark for Open-set Zero-Shot Vision-and-Language Navigation

Given a natural language, a general robot has to comprehend the instruction and find the target object or location based on visual observations even in unexplored environments. Most agents rely on massive diverse training data to achieve better generalization, which requires expensive labor. These agents often focus on common objects and fewer tasks, thus are not intelligent enough to handle different types of instructions. To facilitate research in open-set vision-and-language navigation, we propose a benchmark named MO-VLN, aiming at testing the effectiveness and generalization of the agent in the multi-task setting. First, we develop a 3D simulator rendered by realistic scenarios using Unreal Engine 5, containing more realistic lights and details. The simulator contains three scenes, i.e., cafe, restaurant, and nursing house, of high value in the industry. Besides, our simulator involves multiple uncommon objects, such as takeaway cup and medical adhesive tape, which are more complicated compared with existing environments. Inspired by the recent success of large language models (e.g., ChatGPT, Vicuna), we construct diverse high-quality data of instruction type without human annotation. Our benchmark MO-VLN provides four tasks: 1) goal-conditioned navigation given a specific object category (e.g., "fork"); 2) goal-conditioned navigation given simple instructions (e.g., "Search for and move towards a tennis ball"); 3) step-by-step instruction following; 4) finding abstract object based on high-level instruction (e.g., "I am thirsty").Comment: 18 page

NavCoT: Boosting LLM-Based Vision-and-Language Navigation via Learning Disentangled Reasoning

Vision-and-Language Navigation (VLN), as a crucial research problem of Embodied AI, requires an embodied agent to navigate through complex 3D environments following natural language instructions. Recent research has highlighted the promising capacity of large language models (LLMs) in VLN by improving navigational reasoning accuracy and interpretability. However, their predominant use in an offline manner usually suffers from substantial domain gap between the VLN task and the LLM training corpus. This paper introduces a novel strategy called Navigational Chain-of-Thought (NavCoT), where we fulfill parameter-efficient in-domain training to enable self-guided navigational decision, leading to a significant mitigation of the domain gap in a cost-effective manner. Specifically, at each timestep, the LLM is prompted to forecast the navigational chain-of-thought by: 1) acting as a world model to imagine the next observation according to the instruction, 2) selecting the candidate observation that best aligns with the imagination, and 3) determining the action based on the reasoning from the prior steps. Through constructing formalized labels for training, the LLM can learn to generate desired and reasonable chain-of-thought outputs for improving the action decision. Experimental results across various training settings and popular VLN benchmarks (e.g., Room-to-Room (R2R), Room-across-Room (RxR), Room-for-Room (R4R)) show the significant superiority of NavCoT over the direct action prediction variants. Through simple parameter-efficient finetuning, our NavCoT outperforms a recent GPT4-based approach with ~7% relative improvement on the R2R dataset. We believe that NavCoT will help unlock more task-adaptive and scalable LLM-based embodied agents, which are helpful for developing real-world robotics applications. Code is available at https://github.com/expectorlin/NavCoT

Response of species dominance and niche of plant community to wetland degradation along alpine lake riparian

Alpine wetland degradation threatens riparian biodiversity and ecological balance. Our study, conducted in July 2020 along the northern and eastern shores of Qinghai Lake, seeks to unravel the impacts of such degradation on plant species dominance and ecological niches, using advanced network analysis methods to explore the dynamics and survival strategies of plant species. We applied a space-to-time method to delineate three wetland degradation stage: a healthy swamp wetland, a slightly degraded wet meadow, and a degraded dry meadow. Six representative sampling points were chosen. At each point, three sample lines were randomly established, radiating outward from the center of the lake wetland, with each stage of degradation meticulously examined through three replicates to assess the plant communities in terms of species composition, plant height, coverage, and abundance. The results indicated: Species such as Kobresia tibetica and Leymus secalinus exhibit remarkable abundance across various stages of wetland degradation, indicating a robust tolerance to these conditions. This observation, coupled with the complexity of plant community structures in degrading wetlands, suggests that such intricacy cannot be solely attributed to the dominance of particular species. Instead, it is the result of a diverse array of species adapting to fluctuating water levels, which promotes increased species richness. Despite the prominence of species that exhibit rapid growth and reproduction, the ecological significance of less abundant species in contributing to the community’s complexity is also notable. Changes in habitat conditions due to wetland degradation facilitate both competitive and cooperative interactions among species, highlighting the dynamic nature of these ecosystems. Our analysis shows no significant linear relationship between the ecological niche overlap values and niche widths of plant species. However, the strategies employed by dominant species for competition and resource acquisition, as observed in the ecological niche overlap networks, underscore the adaptive capacity of plant communities. These insights underscore the need for tailored restoration strategies to conserve the biodiversity of alpine lake riparian ecosystems. This research not only sheds light on the resilience and adaptability of ecosystems in the Qinghai-Tibetan Plateau but also offers valuable lessons for the conservation of similar habitats worldwide. Our findings underscore the need for tailored restoration strategies to conserve the biodiversity of alpine lake riparian ecosystems. This research not only sheds light on the resilience and adaptability of ecosystems in the Qinghai-Tibetan Plateau but also offers valuable lessons for the conservation of similar habitats worldwide

Establishment of Elymus natans improves soil quality of a heavily degraded alpine meadow in Qinghai-Tibetan Plateau,

Abstract Elymus natans is a dominant native species widely planted to restore the heavily degraded alpine meadows in Qinghai-Tibetan plateau. The objective of this study was to determine how E. natans establishment affected the quality and fertility of a heavily degraded soil. Soil samples (at depths of 0-10, 10-20 and 20-30 cm) were collected from the 3-and 7-year-old E. natans re-vegetated grasslands, and in the heavily degraded alpine meadow (control). The establishment of E. natans promoted plant cover and aboveground biomass. Compared to the non-reseeded meadow, the concentration of total organic C increased by 13% in the soil under 3-year-old reseeded E. natans grassland at 0-10 cm, and by 7-33% in the soil under 7-year-old reseeded E. natans grassland at 0-10, 10-20 and 20-30 cm depths. Rapid increases in total and available N were also observed in two E. natans re-vegetated grasslands, especially in the 0-10 cm soil layer. Across three sampling depths, total P concentration was increased by 17-35% and 18-54% in 3-and 7-year-old reseeded soil respectively, compared to the soil of control. After 3 years of E. natans growth, microbial biomass C increased by 13-58% at 0-10 and 10-20 cm layers; while it increased by 43-87% in 7-year-old reseeded treatment at 0-10, 10-20 and 20-30 cm depths relative to control. A similar increasing trend was observed for microbial biomass N and P generally. Significant increase in neutral phosphatase, urease, catalase and dehydrogenase was also found in 3-and 7-year-old re-vegetated grasslands compared with heavily degraded meadow. Our results suggest a significant positive impact of E. natans establishment on soil quality. Thus, E. natans establishment could be an effective and applicable measure in restoring heavily degraded alpine meadow in the region of Qinghai-Tibetan Plateau

Establishment of Elymus natans improves soil quality of a heavily degraded alpine meadow in Qinghai-Tibetan Plateau,

Abstract Elymus natans is a dominant native species widely planted to restore the heavily degraded alpine meadows in Qinghai-Tibetan plateau. The objective of this study was to determine how E. natans establishment affected the quality and fertility of a heavily degraded soil. Soil samples (at depths of 0-10, 10-20 and 20-30 cm) were collected from the 3-and 7-year-old E. natans re-vegetated grasslands, and in the heavily degraded alpine meadow (control). The establishment of E. natans promoted plant cover and aboveground biomass. Compared to the non-reseeded meadow, the concentration of total organic C increased by 13% in the soil under 3-year-old reseeded E. natans grassland at 0-10 cm, and by 7-33% in the soil under 7-year-old reseeded E. natans grassland at 0-10, 10-20 and 20-30 cm depths. Rapid increases in total and available N were also observed in two E. natans re-vegetated grasslands, especially in the 0-10 cm soil layer. Across three sampling depths, total P concentration was increased by 17-35% and 18-54% in 3-and 7-year-old reseeded soil respectively, compared to the soil of control. After 3 years of E. natans growth, microbial biomass C increased by 13-58% at 0-10 and 10-20 cm layers; while it increased by 43-87% in 7-year-old reseeded treatment at 0-10, 10-20 and 20-30 cm depths relative to control. A similar increasing trend was observed for microbial biomass N and P generally. Significant increase in neutral phosphatase, urease, catalase and dehydrogenase was also found in 3-and 7-year-old re-vegetated grasslands compared with heavily degraded meadow. Our results suggest a significant positive impact of E. natans establishment on soil quality. Thus, E. natans establishment could be an effective and applicable measure in restoring heavily degraded alpine meadow in the region of Qinghai-Tibetan Plateau

Agents of May Fourth. Jing Yinyu, Xu Zhongnian, and the Early Introduction of Modern Chinese Literature in France

Jing Yinyu (1901-1931?) and Xu Zhongnian (1904-1981) played a pivotal role in the dissemination of modern Chinese literature in France at the turn of the 1930s. Best known as Lu Xun’s first translator into a Western language and a friend of Romain Rolland’s, Jing compiled the Anthologie des conteurs chinois modernes in 1929. In his Anthologie de la littérature chinoise. Des origines à nos jours, published in 1932, Xu also devoted a section to recent literary developments. By analyzing the nature of the two projects, the translated corpora, and their paratexts, I will describe the features of Jing’s and Xu’s dissemination of May Fourth literature in France and scrutinize their artistic and ideological stance vis-à-vis the new literary scene. Ultimately, I will attempt to pinpoint in what terms the two scholars-cum-translators’ agency contributed to foreign readers’ awareness of the cultural, social and political experience of the May Fourth Movement