11 research outputs found
Observations and Problems in Researching the Contemporary Glass-Bead Industry of Northern China
The status of glass-bead manufacturing in northern China is undergoing rapid change due to the development of the plastic-bead industry. Several manufacturing plants, including the large Beijing Glass Ware Factory, are no longer making beads and several other plants are contemplating changes. The variety of domestic glass beads available for purchase today would indicate a greater number of manufacturing sites than are mentioned in the popular literature
Crossâclass pest and disease vegetation detection based on small sample registration
Abstract This paper introduces fewâshot anomaly detection (FSAD), a practical and less anomaly detection (AD) method, which can provide a limited number of normal images for each class during training. So far, studies on FSAD have been carried out according to each model, and there is no discussion of commonalities between different types. Depending on how people detect unusual lies, the problematic images are compared to the normal ones. The image alignment method based on different classifications is used to train the target detection model independent of classification, and performed ablation experiments on the pest and disease datasets in different environments for verification. This is the first time the FSAD method has been used to train a single scalable model without the need to train new classifications or adjust parameters. The experimental results show that the application of AUC based on vegetation disease data set and vegetation pest data set in FSAD algorithm is improved by 19.5% compared with the existing algorithm
In Situ Filler Addition for Homogeneous Dispersion of Carbon Nanotubes in Multi Jet FusionâPrinted Elastomer Composites
Abstract The dispersibility of fillers determines their effect on the mechanical properties and anisotropy of the 3Dâprinted polymeric composites. Nanoscale fillers have the tendency to aggregate, resulting in the deterioration of part performance. An in situ filler addition method using the newly developed dualâfunctional toughness agents (TAs) is proposed in this work for the homogeneous dispersion of carbon nanotubes (CNTs) in elastomer composites printed via multi jet fusion. The CNTs added in the TAs serve as an infrared absorbing colorant for selective powder fusion, as well as the strengthening and toughening fillers. The printability of the TA is theoretically deduced based on the measured physical properties, which are subsequently verified experimentally. The printing parameters and agent formulation are optimized to maximize the mechanical performance of the printed parts. The printed elastomer parts show significant improvement in strength and toughness for all printing orientations and alleviation of the mechanical anisotropy originating from the layerâwise fabrication manner. This in situ filler addition method using tailorable TAs is applicable for fabricating parts with siteâspecific mechanical properties and is promising in assisting the scalable manufacturing of 3Dâprinted elastomers
Surface modification of oriented glass fibers for improving the mechanical properties and flame retardancy of polyamide 12 composites printed by powder bed fusion
The orientation of glass fibers (GF) introduced by powder bed fusion (PBF) imparts enhanced mechanical properties to polyamide 12 (PA12). However, there is still much room for reinforcement of PBF-printed GF/PA12 composites. In addition, no studies have addressed the flame retardancy of PBF-printed GF/PA12 composites impaired by the candlewick-like effect of GF. This work presents a feasible and practical approach for addressing these two issues, by surface modification of GF with layered double hydroxide (LDH) to synthesize LDH@GF hybrids. Compared with the ultimate tensile strength, Young's modulus, flexural strength, and flexural modulus of the GF/PA12 composites, those of the LDH@GF/PA12 composites increased by 21.3%, 54.3%, 31.8%, and 36.7%, respectively. Meanwhile, LDH weakened the candlewick-like effect of GF and thus improved the flame retardancy of the PA12 composites. Compared with the peak heat release rate and total heat release of the GF/PA12 composites, those of LDH@GF/PA12 composites were reduced by 17.7% and 12.7%, respectively. The mechanisms for mechanical reinforcement and flame retardancy of LDH@GF hybrids were investigated and proposed. This work paves the way for PBF to prepare flame-retardant high-strength PA12 composites and provides a new solution to boost the performance of additively manufactured products.This study was supported by the RIE2020 Industry Alignment Fund â Industry Collaboration Projects (IAF-ICP) Funding Initiative, Singapore and the cash and in-kind contributions from our industry partner, HP Inc
Investigation of the mechanical properties of polyimide fiber/polyamide 12 composites printed by Multi Jet Fusion
Multi Jet Fusion (MJF) has attracted extensive attention because of its ability to print support-free complex structures. However, the mechanical properties of MJF-printed polymer parts are still unsatisfactory for certain industrial requirements. Herein, by leveraging the fibre reinforcement effect and high specific strength of polyimide (PI) fibres, this work developed PI/polyamide 12 (PA12) composites with largely enhanced mechanical performance via MJF. Specifically, the tensile strength and modulus were increased by 43% and 42%, and the flexural strength and modulus were improved by 39% and 46%, respectively, compared to those of the neat PA12 parts. Furthermore, the incorporation of lightweight PI fibres endowed the composites with high specific tensile strength (67.60 kN·m/kg) and specific flexural strength (93.70 kN·m/kg), which are superior to those of MJF-printed PA12 composites reinforced with other fibres. This work provides new insights into enhancing the mechanical performance of lightweight parts printed by MJF and other powder-based techniques
DataSheet_1_Chinese famine exposure in early life and metabolic obesity phenotype in middle age: Results from the China health and retirement longitudinal study.docx
ObjectiveTo assess the association between early life exposure to famine and the risk of metabolic obesity phenotypes among adults in middle age.MethodsThe study selected two comparison groups. Comparison A consisted of a non-exposed group born between 1963-1965 from the China Health and Retirement Longitudinal Study (CHARLS) 2015 wave (N=862) and a fetal-exposed group born between 1959-1961 from the 2011 wave (N=507). Comparison B consisted of an early childhood-exposed group born between 1955-1957 from the 2011 wave (N=830) and a fetal-exposed group born between 1959-1961 from the 2015 wave (N=552). Multivariable logistic regressions were conducted to explore the associations between different periods of famine exposure and obesity, metabolic health status, and metabolic obesity phenotypes, with stratification by sex.ResultsCompared with the non-exposed group, participants exposed to famine in the fetal period had a significantly lower risk of overweight/obesity (OR: 0.78, 95%CI: 0.63-0.97) and a higher risk of metabolically unhealthy status (OR: 1.73, 95%CI: 1.34-2.23) and metabolically unhealthy non-obesity (MUNO) (OR: 2.12, 95%CI: 1.46-3.08) at the age of 50-52 years. In the sex-stratified analysis, males exposed to famine in the fetal period had a significantly lower risk of overweight/obesity (OR: 0.59, 95%CI: 0.43-0.80) and metabolically healthy obesity (MHO) (OR: 0.56, 95%CI: 0.37-0.85), while such associations were not found in females. Compared with the early childhood exposure group, participants in the fetal exposure group had a significantly lower risk of metabolic unhealthy status (OR: 0.65, 95%CI: 0.51-0.85) and MUNO (OR: 0.50, 95%CI: 0.35-0.72). Those associations were observed in both males and females.ConclusionExposure to famine in early life increased the risk of metabolically unhealthy status in adulthood. Different metabolic subtypes should be identified at an early stage and followed by classification, intervention, and treatment.</p
DataSheet_3_Chinese famine exposure in early life and metabolic obesity phenotype in middle age: Results from the China health and retirement longitudinal study.pdf
ObjectiveTo assess the association between early life exposure to famine and the risk of metabolic obesity phenotypes among adults in middle age.MethodsThe study selected two comparison groups. Comparison A consisted of a non-exposed group born between 1963-1965 from the China Health and Retirement Longitudinal Study (CHARLS) 2015 wave (N=862) and a fetal-exposed group born between 1959-1961 from the 2011 wave (N=507). Comparison B consisted of an early childhood-exposed group born between 1955-1957 from the 2011 wave (N=830) and a fetal-exposed group born between 1959-1961 from the 2015 wave (N=552). Multivariable logistic regressions were conducted to explore the associations between different periods of famine exposure and obesity, metabolic health status, and metabolic obesity phenotypes, with stratification by sex.ResultsCompared with the non-exposed group, participants exposed to famine in the fetal period had a significantly lower risk of overweight/obesity (OR: 0.78, 95%CI: 0.63-0.97) and a higher risk of metabolically unhealthy status (OR: 1.73, 95%CI: 1.34-2.23) and metabolically unhealthy non-obesity (MUNO) (OR: 2.12, 95%CI: 1.46-3.08) at the age of 50-52 years. In the sex-stratified analysis, males exposed to famine in the fetal period had a significantly lower risk of overweight/obesity (OR: 0.59, 95%CI: 0.43-0.80) and metabolically healthy obesity (MHO) (OR: 0.56, 95%CI: 0.37-0.85), while such associations were not found in females. Compared with the early childhood exposure group, participants in the fetal exposure group had a significantly lower risk of metabolic unhealthy status (OR: 0.65, 95%CI: 0.51-0.85) and MUNO (OR: 0.50, 95%CI: 0.35-0.72). Those associations were observed in both males and females.ConclusionExposure to famine in early life increased the risk of metabolically unhealthy status in adulthood. Different metabolic subtypes should be identified at an early stage and followed by classification, intervention, and treatment.</p
DataSheet_2_Chinese famine exposure in early life and metabolic obesity phenotype in middle age: Results from the China health and retirement longitudinal study.docx
ObjectiveTo assess the association between early life exposure to famine and the risk of metabolic obesity phenotypes among adults in middle age.MethodsThe study selected two comparison groups. Comparison A consisted of a non-exposed group born between 1963-1965 from the China Health and Retirement Longitudinal Study (CHARLS) 2015 wave (N=862) and a fetal-exposed group born between 1959-1961 from the 2011 wave (N=507). Comparison B consisted of an early childhood-exposed group born between 1955-1957 from the 2011 wave (N=830) and a fetal-exposed group born between 1959-1961 from the 2015 wave (N=552). Multivariable logistic regressions were conducted to explore the associations between different periods of famine exposure and obesity, metabolic health status, and metabolic obesity phenotypes, with stratification by sex.ResultsCompared with the non-exposed group, participants exposed to famine in the fetal period had a significantly lower risk of overweight/obesity (OR: 0.78, 95%CI: 0.63-0.97) and a higher risk of metabolically unhealthy status (OR: 1.73, 95%CI: 1.34-2.23) and metabolically unhealthy non-obesity (MUNO) (OR: 2.12, 95%CI: 1.46-3.08) at the age of 50-52 years. In the sex-stratified analysis, males exposed to famine in the fetal period had a significantly lower risk of overweight/obesity (OR: 0.59, 95%CI: 0.43-0.80) and metabolically healthy obesity (MHO) (OR: 0.56, 95%CI: 0.37-0.85), while such associations were not found in females. Compared with the early childhood exposure group, participants in the fetal exposure group had a significantly lower risk of metabolic unhealthy status (OR: 0.65, 95%CI: 0.51-0.85) and MUNO (OR: 0.50, 95%CI: 0.35-0.72). Those associations were observed in both males and females.ConclusionExposure to famine in early life increased the risk of metabolically unhealthy status in adulthood. Different metabolic subtypes should be identified at an early stage and followed by classification, intervention, and treatment.</p