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1.
J Xray Sci Technol ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38669513

RESUMO

BACKGROUND: Recently, X-rays have been widely used to detect complex structural workpieces. Due to the uneven thickness of the workpiece and the high dynamic range of the X-ray image itself, the detailed internal structure of the workpiece cannot be clearly displayed. OBJECTIVE: To solve this problem, we propose an image enhancement algorithm based on a multi-scale local edge-preserving filter. METHODS: Firstly, the global brightness of the image is enhanced through logarithmic transformation. Then, to enhance the local contrast, we propose utilizing the gradient decay function based on fuzzy entropy to process the gradient and then incorporate the gradient into the energy function of the local edge-preserving filter (LEP) as a constraint term. Finally, multiple base layers and detail layers are obtained through filtering multi-scale decomposition. All detail layers are enhanced and fused using S-curve mapping to improve contrast further. RESULTS: This method is competitive in both quantitative indices and visual perception quality. CONCLUSIONS: The experimental results demonstrate that the proposed method significantly enhances various complex workpieces and is highly efficient.

3.
Appl Opt ; 62(20): 5526-5537, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37706871

RESUMO

X-ray images frequently have low contrast and lost edge features because of the complexity of objects, attenuation of reflected light, and scattering superposition of rays. Image features are frequently lost in traditional enhancement methods. In this paper, we use a ray scattering model to estimate coarsely clear images and an encoder-decoder network and multi-scale feature extraction module to add multi-scale and detail information to the images. To selectively emphasize useful features, a dual attention module and UnsharpMasking with learnable correction factors are used. The results of the experiments demonstrate that the method may significantly enhance the quality of x-ray images.

5.
J Sci Food Agric ; 103(7): 3306-3314, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36737411

RESUMO

BACKGROUND: Numerous positive effects have been attributed to lutein, a lipophilic nutrient, including resisting ultraviolet radiation and protecting retinal pigment epithelial (RPE) cells against blue light damage. It also has preventive effects against cardiovascular disease and cancer. However, its use could be limited by its poor stability and low bioaccessibility in the human digestive system. An encapsulation delivery system was therefore developed to resolve these limitations. In this study, chitosan-modified lutein nanoliposomes (CS-LNLs), chitosan-EGCG covalently modified lutein nanoliposomes (C-CS-EGCG-LNLs), and chitosan-EGCG noncovalently modified lutein nanoliposomes (non-C-CS-EGCG-LNLs) were designed. The average particle size, ζ-potential, and retention of lutein during storage were measured to indicate the physicochemical stability of the modified lutein nanoliposomes. The bioaccessibility of modified lutein nanoliposomes was also investigated to demonstrate the availability of lutein in the human digestive system. RESULTS: First, Fourier-transform infrared spectroscopy (FTIR) verified that covalent bonds between chitosan and EGCG were formed. Subsequently, ζ-potential results revealed that C-CS-EGCG-LNLs had a relatively stable structure in comparison with lutein nanoliposomes (LNLs). The retention rate of lutein in CS-LNLs, C-CS-EGCG-LNLs, and non-C-CS-EGCG-LNLs was improved, especially in C-CS-EGCG-LNLs (at around 70% of lutein in initial system). An in vitro digestion experiment illustrated that CS-LNLs, C-CS-EGCG-LNLs, and non-C-CS-EGCG-LNLs presented relatively higher bioaccessibility, especially in C-CS-EGCG-LNLs (at around 33% of luein in initial system), which increased 2.5 and 1.65 times in comparison with free lutein and LNLs, respectively. CONCLUSION: Overall, the results showed that C-CS-EGCG-LNLs presented greater physicochemical stability and bioaccessibility than LNLs, CS-LNLs, and non-C-CS-EGCG-LNLs. © 2023 Society of Chemical Industry.


Assuntos
Catequina , Quitosana , Nanopartículas , Humanos , Antioxidantes/química , Catequina/química , Quitosana/química , Luteína , Nanopartículas/química , Tamanho da Partícula , Raios Ultravioleta
6.
Technol Health Care ; 31(2): 607-620, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36155538

RESUMO

BACKGROUND: The Ling sound test cannot provide the test of Chinese tone for preschool children with hearing aid and cochlear implants. OBJECTIVE: The paper tries to design a new tone test method composed of the Ling sound test and four Chinese tones to evaluate the hearing level of Chinese hearing-impaired children. METHODS: The tone identification rates of 20 cochlear implant children were statistically analyzed to verify the validity of the Ling sound test in the Chinese tone version. In addition, this paper analyzed the pronunciation characteristics of the Ling sound test in the Chongqing-accented Mandarin version of 20 subjects. RESULTS: The identification rate of Ling six sounds was more than 97.0%, the identification rate of tone was more than 81.0%, and the identification rate of vowels was 83.1%, which was higher than that of consonants 79.0%. The Ling sound test n the Chongqing-accented Mandarin version has a narrower frequency range. CONCLUSION: The results verify the effectiveness and feasibility of the Ling sound test in the Chinese tone version in the assessment of frequency range and tone identification for cochlear implant users.


Assuntos
Implantes Cocleares , Surdez , Auxiliares de Audição , Percepção da Fala , Pré-Escolar , Humanos , Surdez/reabilitação , Idioma
7.
Polymers (Basel) ; 14(22)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36433066

RESUMO

In this study, hot stamping tests on continuous glass fiber (GF)-reinforced thermoplastic (PP) composites were conducted under different process parameters using a self-designed hemispherical hot stamping die with a heating system. The effects of parameters such as preheating temperature, stamping depth, and stamping speed on the formability of the fabricated parts were analyzed using optical microscopy and scanning electron microscopy (SEM). The test results show that the suitable stamping depth should be less than 15 mm, the stamping speed should be less than 150 mm/min, and the preheating temperature should be about 200 °C. From the edge of the formed parts to their pole area, a thin-thick-thin characteristic in thickness was observed. Under the same preheating temperature, the influence of stamping depth on the thickness variation of the formed parts was more significant than the stamping speed. The primary defects of the formed parts were cracking, wrinkling, delamination, and fiber exposure. Resin poverty often occurred in the defect area of the formed parts and increased with stamping depth and stamping speed.

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