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"Zhu, Zheng-wei"
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Model Experimental Study on Stress Transfer and Redistribution in a Clay Landslide under Surcharge Load
Stress transfer and redistribution always accompany with the evolution of landslides. However, previous literature studies have mainly focused on stages of stress variation, and far too little attention has been paid to detailed transfer and redistribution process analysis on stress variation. In this paper, a large-scale clay model slope with masonry slide bed and prefabricated cambered slip surface was constructed. Earth pressure cells were embedded into slip mass to monitor vertical and horizontal stresses in different parts of the test soils under the set load sequence. Stress transfer efficiency (STE) indicators based on qualified stress monitoring datasets (tested by Shapiro-Wilk method) were established to quantify the stress transfer process. Staged development of stress inside the clay slope was analyzed through extracting slopes of stress curves and limit loads. The stress redistribution process was analyzed using STE and deflection of stress isolines derived from numerical simulation. Moreover, to study the influence of loading position on stress variation, geometry partitioning has also been discussed. Results showed that vertical and horizontal stresses had different growth trends on both sides of 80 kN and 60 kN, respectively. Horizontal stress growth has two stages; vertical stress growth has two stages in soils close to slope surface and shear outlet, while there are three stages in other soils. Vertical stress transfer efficiency (VSTE) and horizontal stress transfer efficiency (HSTE) are recommended to quantify stress transfer and redistribution process. Based on VSTEs and HSTEs, the slip mass could be partitioned into three parts: loading zone, transfer zone, and free zone. Deflecting amplitudes of stress isolines were in consistency with the results revealed by STEs.
Journal Article
A physics-informed machine learning solution for landslide susceptibility mapping based on three-dimensional slope stability evaluation
Landslide susceptibility mapping is a crucial tool for disaster prevention and management. The performance of conventional data-driven model is greatly influenced by the quality of the samples data. The random selection of negative samples results in the lack of interpretability throughout the assessment process. To address this limitation and construct a high-quality negative samples database, this study introduces a physics-informed machine learning approach, combining the random forest model with Scoops 3D, to optimize the negative samples selection strategy and assess the landslide susceptibility of the study area. The Scoops 3D is employed to determine the factor of safety value leveraging Bishop’s simplified method. Instead of conventional random selection, negative samples are extracted from the areas with a high factor of safety value. Subsequently, the results of conventional random forest model and physics-informed data-driven model are analyzed and discussed, focusing on model performance and prediction uncertainty. In comparison to conventional methods, the physics-informed model, set with a safety area threshold of 3, demonstrates a noteworthy improvement in the mean AUC value by 36.7%, coupled with a reduced prediction uncertainty. It is evident that the determination of the safety area threshold exerts an impact on both prediction uncertainty and model performance.
Journal Article
Experimental Study on Slope Deformation Monitoring Based on a Combined Optical Fiber Transducer
Landslide monitoring is very important in predicting the behavior of landslides, thereby ensuring environment, life, and property safety. On the basis of our previous studies, a novel combined optic fiber transducer (COFT) for landslides monitoring and the related analysis methods are presented. Based on the principles of optical fiber microbending loss, the empirical formula of the shearing displacement of sliding body versus optical loss was established through a stretching test of optical fiber bowknot. Then the COFT grouting direct shearing tests, a large-scale landslide model test, and numerical modeling verification with FLAC3D are carried out. According to the results, the initial measurement precision of the designed COFT in sandy clay is 1 mm; its monitoring sliding distance is larger than 26.5 mm. The calculated values based on empirical formula are in good agreement with the laboratory tests and numerical simulation results. When the ratio of cement and sand in mortar is 1 : 5, the error between the calculated displacement and the measured displacement of sliding surface is the smallest. The COFT with expandable polystyrene (EPS) as its base material performs better in monitoring sandy clay slopes because both the error and the mean square deviation of the empirical formula are smaller.
Journal Article
A Type-Based Blocking Technique for Efficient Entity Resolution over Large-Scale Data
In data integration, entity resolution is an important technique to improve data quality. Existing researches typically assume that the target dataset only contain string-type data and use single similarity metric. For larger high-dimensional dataset, redundant information needs to be verified using traditional blocking or windowing techniques. In this work, we propose a novel ER-resolving method using a hybrid approach, including type-based multiblocks, varying window size, and more flexible similarity metrics. In our new ER workflow, we reduce the searching space for entity pairs by the constraint of redundant attributes and matching likelihood. We develop a reference implementation of our proposed approach and validate its performance using real-life dataset from one Internet of Things project. We evaluate the data processing system using five standard metrics including effectiveness, efficiency, accuracy, recall, and precision. Experimental results indicate that the proposed approach could be a promising alternative for entity resolution and could be feasibly applied in real-world data cleaning for large datasets.
Journal Article
Shipborne radar maneuvering target tracking based on the variable structure adaptive grid interacting multiple model
The trajectory of a shipborne radar target has a certain complexity, randomness, and diversity. Tracking a strong maneuvering target timely, accurately, and effectively is a key technology for a shipborne radar tracking system. Combining a variable structure interacting multiple model with an adaptive grid algorithm, we present a variable structure adaptive grid interacting multiple model maneuvering target tracking method. Tracking experiments are performed using the proposed method for five maneuvering targets, including a uniform motion — uniform acceleration motion target, a uniform acceleration motion — uniform motion target, a serpentine locomotion target, and two variable acceleration motion targets. Experimental results show that the target position, velocity, and acceleration tracking errors for the five typical target trajectories are small. The method has high tracking precision, good stability, and flexible adaptability.
Journal Article
Association analyses confirm five susceptibility loci for systemic lupus erythematosus in the Han Chinese population
Introduction
Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease. Currently, numerous genetic loci of SLE have been confirmed. Here we try to further explore additional genes contributing to SLE susceptibility in this study.
Methods
Forty nine single nucleotide polymorphisms (SNPs) with moderate-risk for SLE in previous study were genotyped in a large-scale replication study with a total of 3,522 cases and 8,252 controls using the Sequenom Massarray system. Association analyses were performed using logistic regression with gender or sample cohorts as a covariate through PLINK 1.07 software.
Results
This replication effort confirmed five reported SLE susceptibility loci reaching genome-wide levels of significance (
P
meta
<5.00 × 10
−08
):
TNFSF4
(rs1418190, odds ratio (OR) = 0.81,
P
meta
= 1.08 × 10
−08
; rs4916219, OR = 0.80,
P
meta
= 7.77 × 10
−09
),
IRF8
(rs2934498, OR = 1.25,
P
meta
= 4.97 × 10
−09
),
miR-146a
(rs2431697, OR = 0.69,
P
meta
= 1.15 × 10
−22
),
CD44
(rs2732547, OR = 0.82,
P
meta
= 1.55 × 10
−11
), and
TMEM39A
(rs12494314, OR = 0.84,
P
meta
= 1.01 × 10
−09
). Further logistic regression analysis indicated that the genetic effects within
TNFSF4
detected in this study are independent from our previously reported signals.
Conclusions
This study increases the number of established susceptibility loci for SLE in Han Chinese population and highlights the contribution of multiple variants of modest effect. Although further studies will be required to identify the causal alleles within these loci, the findings make a significant step forward in our understanding of the genetic contribution to SLE in Chinese population.
Journal Article
A novel method of augmenting gene expression and angiogenesis in the normal and ischemic canine myocardium
This study presents a novel method that direct intramyocardial injection of low-dose plasmid DNA and microbubbles combined with insonation could further augment gene expression in normal and ischemic canine myocardium. Plasmids encoding enhanced green fluorescent protein (pEGFP) and hepatocyte growth factor (pHGF) (500 μg) were individually mixed with 0.5 ml of microbubble solution (MB) and injected into the normal or acute ischemic canine myocardium. The dogs in the plasmid + MB/US group underwent insonation (US). Other dogs were randomly divided into three treatment groups: plasmid and insonation, plasmid and MB injection, and plasmid injection only. The EGFP and HGF mRNA expressions were assessed in the myocardium at the injection site and at sites 0.5 and 1 cm remote from the injection site. Compared to plasmid transfer alone, a mean 13.4-fold enhancement of gene expression was achieved in the EGFP + MB/US group at 48 h (p < 0.01). HGF mRNA expression in ischemic zones was markedly elevated after 28 days, with a mean 9.0-fold enhancement in the HGF + MB/US group (p < 0.01). EGFP protein expression was detected in the normal myocardium at 1 cm remote from the injection site in the EGFP + MB/US group. Similarly, HGF protein expression was detected in the ischemic myocardium at 0.5 cm remote from the injection site in the HGF + MB/US group. These findings indicate that the radius of gene expression was partly extended in the two plasmid + MB/US groups. The capillary density increased from 20.9 ± 5.3/mm(2) in control myocardial infarction dogs without treatment to 126.7 ± 38.2/mm(2) in the HGF + MB/US group (p < 0.01). Taken together, the present data demonstrate that direct intramyocardial injection of an angiogenic gene and microbubbles combined with insonation can augment gene expression and angiogenesis. Consequently, this strategy may be a useful tool for gene therapy of ischemic heart disease.
Journal Article
Increased expression of IL-28RA mRNA in peripheral blood mononuclear cells from patients with systemic lupus erythematosus
Systemic lupus erythematosus (SLE) is a systemic autoimmune and inflammatory disease with a strong genetic contribution and characterized by kinds of immune reactions. Our previous genome-wide association studies have identified
IL
-
28RA
as a susceptibility gene for SLE. In this study, we performed a quantitative reverse transcription polymerase chain reaction (RT-PCR) in 62 patients with SLE and 69 controls to investigate the different expression levels of
IL
-
28RA
in peripheral blood mononuclear cells (PBMCs) from SLE patients and healthy controls and the association between
IL
-
28RA
expression and systemic lupus erythematosus disease activity index (SLEDAI) or the variant of the single-nucleotide polymorphism (SNP) rs4649203. The expression levels of
IL
-
28RA
messenger RNA (mRNA) in SLE patients were significantly increased compared with those of healthy controls. In addition, there were also significant differences in the expression levels of
IL
-
28RA
between active (SLEDAI ≥ 6) or inactive (SLEDAI < 6) SLE groups and healthy controls. However, no correlation was observed between
IL
-
28RA
mRNA expression level and SLEDAI. There was no association between the variant of the SNP rs4649203 and
IL
-
28RA
mRNA expression levels neither. These results indicated that expression of
IL
-
28RA
mRNA may be correlated with the pathogenesis of SLE.
Journal Article