83 research outputs found
Winkler model for dynamic response of composite caisson-piles foundations: Lateral response
As the first part of a sequence focusing on the dynamic response of composite caisson-piles foundations (CCPFs1), this paper develops a simplified method for the lateral response of these foundations. A Winkler model for the lateral vibration of the CCPF is created by joining the two components, the caisson and the pile group, where the four-spring Winkler model is utilized for the caisson and axial-lateral coupled vibration equations are derived for the pile group. For determining the coefficients of the four-spring Winkler model for the caissons, embedded footing impedance is used and a modification on the rotational embedment factor is made for the sake of the geometrical difference between shallow footings and caissons. Comparisons against results from finite element simulations demonstrate the reliability of this modified four-spring Winkler model for caissons in both homogenous and layered soils. The proposed simplified method for the lateral vibration of CCPFs is verified also by 3D finite element modeling. Finally, through an example, the idea of adding piles beneath the caisson is proved to be of great significance to enhance the resistance of the foundation against lateral dynamic loads
CPET: Effective Parameter-Efficient Tuning for Compressed Large Language Models
Parameter-efficient tuning (PET) has been widely explored in recent years
because it tunes much fewer parameters (PET modules) than full-parameter
fine-tuning (FT) while still stimulating sufficient knowledge from large
language models (LLMs) for downstream tasks. Moreover, when PET is employed to
serve multiple tasks, different task-specific PET modules can be built on a
frozen LLM, avoiding redundant LLM deployments. Although PET significantly
reduces the cost of tuning and deploying LLMs, its inference still suffers from
the computational bottleneck of LLMs. To address the above issue, we propose an
effective PET framework based on compressed LLMs, named "CPET". In CPET, we
evaluate the impact of mainstream LLM compression techniques on PET performance
and then introduce knowledge inheritance and recovery strategies to restore the
knowledge loss caused by these compression techniques. Our experimental results
demonstrate that, owing to the restoring strategies of CPET, collaborating
task-specific PET modules with a compressed LLM can achieve comparable
performance to collaborating PET modules with the original version of the
compressed LLM and outperform directly applying vanilla PET methods to the
compressed LLM
An Extensible Plug-and-Play Method for Multi-Aspect Controllable Text Generation
Recently, multi-aspect controllable text generation that controls the
generated text in multiple aspects (e.g., sentiment, topic, and keywords) has
attracted increasing attention. Although methods based on parameter efficient
tuning like prefix-tuning could achieve multi-aspect controlling in a
plug-and-play way, the mutual interference of multiple prefixes leads to
significant degeneration of constraints and limits their extensibility to
training-time unseen aspect combinations. In this work, we provide a
theoretical lower bound for the interference and empirically found that the
interference grows with the number of layers where prefixes are inserted. Based
on these analyses, we propose using trainable gates to normalize the
intervention of prefixes to restrain the growing interference. As a result,
controlling training-time unseen combinations of aspects can be realized by
simply concatenating corresponding plugins such that new constraints can be
extended at a lower cost. In addition, we propose a unified way to process both
categorical and free-form constraints. Experiments on text generation and
machine translation demonstrate the superiority of our approach over baselines
on constraint accuracy, text quality, and extensibility.Comment: long paper, accepted by ACL 2023 (main conference
Soil cover improves soil quality in a young walnut forest in the Sichuan Basin, China
The soil quality index (SQI) is based on several key indicators and is used to assess soil quality. More than 250,000 ha of walnut saplings (Juglans regia L.) were planted in previous cropland areas in the Sichuan Basin, China, using a range of soil cover types that may affect soil quality with effects that are unclear. We investigated the effects of white film (WF), black film (BF), shade netting (SN), and maize straw (MS) soil cover types and an uncovered control type (CK) on soil chemical and biological indicators and the SQI in the 0-15 cm soil layer in a young walnut forest in the Sichuan Basin over a 27-month study period. The results showed that all soil cover types increased the soil organic matter (SOM), total potassium (TK), and available potassium (AK) concentrations (p < 0.05), whereas the total nitrogen (TN) and available nitrogen (AN) concentrations were greater only in soils covered by MS than in CK (p < 0.05). The available phosphorus concentrations were 64.1 and 193.2% greater in soils covered by BF and MS treatments, respectively, than in the CK (p < 0.05). The numbers of soil faunal groups (N) were 45.7, 36.4, 37.2, and 101.5% higher in WF, BF, SN, and MS, respectively, than in CK (p < 0.05); the individual numbers (S) were 92.3, 36.2, 100.8, and 154.5% greater in WF, BF, SN, and MS, respectively, than in CK (p < 0.05). The microbial biomass carbon (MBC) was 15.5, 32.3, 45.0, and 77.1% greater in WF, BF, SN, and MS than in CK, respectively (p < 0.05). Redundancy discriminant analysis revealed strong positive interactions between biological indicators (MBC, N, and S) and SOM, AN, and AK concentrations. SOM, TN, AK, S, and MBC were the minimum required variables for the effective assessment of the SQI. All four soil cover types led to an improved SQI (p < 0.05), and MS had the greatest effect on SOM, TN, AN, AP, N, S, MBC, and SQI (p < 0.05). In conclusion, all four soil cover types increased the SOM levels, TK, AK, and MBC concentrations, soil faunal diversity, and SQI. The MS treatment was the most cost-effective and efficient measure to improve soil fertility, ecological function, and overall soil quality in the studied walnut forest
- …