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ANALYSIS ON GRAY NODES AND GRAYNESS DEGREE IN COMPLEX NETWORK 被引量:1
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作者 崔博 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期125-130,共6页
Based on the theory of complex network and gray system, the sugesstion that there exist two types of gray nodes in complex networks, Gray Node I and Gray Node II, is concluded. The first one refers to the existent unk... Based on the theory of complex network and gray system, the sugesstion that there exist two types of gray nodes in complex networks, Gray Node I and Gray Node II, is concluded. The first one refers to the existent unknown gray nodes, and the second the evolution gray nodes. The relevant definitions are also given. Further- more, grayness degree in complex networks is described and divided into two forms--the relative grayness degree (RGD) and the absolute grayness degree (AGD), which are proved respectively. 展开更多
关键词 gray system complex network gray nodes grayness degree
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基于广义Gray码变换和广义Arnold映射的彩色图像加密算法
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作者 郭蓉蓉 陈星 +1 位作者 赵红旗 叶瑞松 《交叉科学快报》 2025年第3期380-393,共14页
本文通过结合混沌系统与数据编码,提出了一种新型彩色图像加密算法。该算法通过离散型广义Arnold映射对明文像素位置进行非线性置乱,破坏相邻像素相关性;引入广义Gray码变换对置乱后图像颜色分量值实施编码,初步隐藏视觉信息;利用连续... 本文通过结合混沌系统与数据编码,提出了一种新型彩色图像加密算法。该算法通过离散型广义Arnold映射对明文像素位置进行非线性置乱,破坏相邻像素相关性;引入广义Gray码变换对置乱后图像颜色分量值实施编码,初步隐藏视觉信息;利用连续型广义Arnold映射生成伪随机密钥流,对编码图像完成扩散运算,进一步破坏明文统计特征。加密算法融合了广义Gray码变换的局部混淆能力和广义Arnold映射的全局扩散特性,构建双重安全机制。一方面,离散型广义Arnold映射和广义Gray编码协同增强像素位置与灰度值的动态扰乱效果;另一方面,连续型广义Arnold映射扩展了加密算法的密钥空间。数值实验表明,该图像加密算法具有优良的加密性能,可以抵御蛮力攻击、统计分析攻击以及差分攻击等。The paper proposes a novel image encryption algorithm by integrating chaotic system with data coding. The algorithm employs a discrete generalized Arnold map to nonlinearly scramble plain image’s pixel positions, effectively disrupting adjacent pixel correlations. A generalized gray code transformation is introduced to perform encoding on color component values of the scrambled image, achieving preliminary visual information concealment. Subsequently, a continuous generalized Arnold map generates pseudo-random keystreams to execute diffusion operations on the encoded image, further eliminating statistical features of the plain image. Combining the local confusion capability of generalized gray code transformation with the global diffusion nature of generalized Arnold map, the encryption algorithm establishes a dual security mechanism. On the one hand, the collaborative effect of discrete generalized Arnold map and generalized gray coding enhances dynamic disruption of pixel positions and grayscale values;on the other hand, the continuous generalized Arnold map significantly expands the key space of the proposed encryption. Numerical experiments demonstrate that the proposed image encryption algorithm exhibits excellent performance and security, showing strong resistance against differential analysis attack, statistical attacks and brute-force attack, etc. 展开更多
关键词 图像加密 广义Gray码 广义Arnold映射 混沌映射
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基于广义Gray码和DCT-SVD的数字水印算法研究
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作者 易建隆 陈星月 +2 位作者 黄昱霖 胡橼丹 高仕龙 《图像与信号处理》 2025年第4期486-495,共10页
本文提出一种基于广义Gray码、离散余弦变换与奇异值分解的数字水印算法,有效提升了水印的鲁棒性。该算法先对水印信息实施广义Gray码变换,后通过分块离散余弦变换和奇异值分解,将水印嵌入到载体图像中频段的奇异值里。实验结果表明,相... 本文提出一种基于广义Gray码、离散余弦变换与奇异值分解的数字水印算法,有效提升了水印的鲁棒性。该算法先对水印信息实施广义Gray码变换,后通过分块离散余弦变换和奇异值分解,将水印嵌入到载体图像中频段的奇异值里。实验结果表明,相较于已有算法,该算法在JPEG压缩、噪声干扰、裁剪、旋转等多种攻击下,归一化相关系数表现更优,具备更强的鲁棒性。 展开更多
关键词 数字水印 离散余弦变换 奇异值分解 广义Gray码 鲁棒性
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Fetal Gray Matter Heterotopia 被引量:1
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作者 Jiaojiao Liu Lianxiang Xiao 《iRADIOLOGY》 2025年第3期231-233,共3页
A pregnant woman underwent fetal brain magnetic resonance imaging(MRI)following ultrasound detection of a posterior fossa cyst at 29 weeks'gestation.She presented with no relevant medical history and underwent a r... A pregnant woman underwent fetal brain magnetic resonance imaging(MRI)following ultrasound detection of a posterior fossa cyst at 29 weeks'gestation.She presented with no relevant medical history and underwent a routine obstetric examination during pregnancy.The fetal head position,fetal cranial development,and limb development remained normal until 29 weeks. 展开更多
关键词 fetal magnetic resonance imaging FETUS gray matter heterotopia
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5DGWO-GAN:A Novel Five-Dimensional Gray Wolf Optimizer for Generative Adversarial Network-Enabled Intrusion Detection in IoT Systems
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作者 Sarvenaz Sadat Khatami Mehrdad Shoeibi +2 位作者 Anita Ershadi Oskouei Diego Martín Maral Keramat Dashliboroun 《Computers, Materials & Continua》 SCIE EI 2025年第1期881-911,共31页
The Internet of Things(IoT)is integral to modern infrastructure,enabling connectivity among a wide range of devices from home automation to industrial control systems.With the exponential increase in data generated by... The Internet of Things(IoT)is integral to modern infrastructure,enabling connectivity among a wide range of devices from home automation to industrial control systems.With the exponential increase in data generated by these interconnected devices,robust anomaly detection mechanisms are essential.Anomaly detection in this dynamic environment necessitates methods that can accurately distinguish between normal and anomalous behavior by learning intricate patterns.This paper presents a novel approach utilizing generative adversarial networks(GANs)for anomaly detection in IoT systems.However,optimizing GANs involves tuning hyper-parameters such as learning rate,batch size,and optimization algorithms,which can be challenging due to the non-convex nature of GAN loss functions.To address this,we propose a five-dimensional Gray wolf optimizer(5DGWO)to optimize GAN hyper-parameters.The 5DGWO introduces two new types of wolves:gamma(γ)for improved exploitation and convergence,and theta(θ)for enhanced exploration and escaping local minima.The proposed system framework comprises four key stages:1)preprocessing,2)generative model training,3)autoencoder(AE)training,and 4)predictive model training.The generative models are utilized to assist the AE training,and the final predictive models(including convolutional neural network(CNN),deep belief network(DBN),recurrent neural network(RNN),random forest(RF),and extreme gradient boosting(XGBoost))are trained using the generated data and AE-encoded features.We evaluated the system on three benchmark datasets:NSL-KDD,UNSW-NB15,and IoT-23.Experiments conducted on diverse IoT datasets show that our method outperforms existing anomaly detection strategies and significantly reduces false positives.The 5DGWO-GAN-CNNAE exhibits superior performance in various metrics,including accuracy,recall,precision,root mean square error(RMSE),and convergence trend.The proposed 5DGWO-GAN-CNNAE achieved the lowest RMSE values across the NSL-KDD,UNSW-NB15,and IoT-23 datasets,with values of 0.24,1.10,and 0.09,respectively.Additionally,it attained the highest accuracy,ranging from 94%to 100%.These results suggest a promising direction for future IoT security frameworks,offering a scalable and efficient solution to safeguard against evolving cyber threats. 展开更多
关键词 Internet of things intrusion detection generative adversarial networks five-dimensional binary gray wolf optimizer deep learning
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Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study
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作者 Kaixuan Zhou Gaoxiong Duan +19 位作者 Ying Liu Bei Peng Xiaoyan Zhou Lixia Qin Lingyan Liang Yichen Wei Qingping Zhang Xiaocheng Li Haixia Qin Yinqi Lai Yian Lu Yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming Zhao Jun Liu Jianrong Yang Demao Deng 《Neural Regeneration Research》 SCIE CAS 2025年第10期3013-3024,共12页
Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 infections.Previous studies have demonstrated abnormal b... Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 infections.Previous studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase data.As a result,little is known about the pathophysiology of sleep disturbances in the acute phase of COVID-19.To address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this study.Eleven COVID-19 patients with sleep disturbances were included in a longitudinal analysis.We found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain lobes.The cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index scores.Additionally,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy controls.The 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep disturbances.Our findings indicate that the sleep disturbances patients had altered morphology in the cortical and hippocampal structures during the acute phase of infection and persistent changes in cortical regions at 3 months post-infection.These data improve our understanding of the pathophysiology of sleep disturbances caused by COVID-19. 展开更多
关键词 brain structure cortical gray matter volume cortical surface area cortical thickness HIPPOCAMPUS magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume
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Study on Color Difference of Color Reproduction of 3D Objects
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作者 GU Chong DENG Yi-qiang 《印刷与数字媒体技术研究》 北大核心 2025年第4期33-38,69,共7页
To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,a... To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,and TL84)on 3D color difference evaluations,50 glossy spheres with a diameter of 2cm based on the Sailner J4003D color printing device were created.These spheres were centered around the five recommended colors(gray,red,yellow,green,and blue)by CIE.Color difference was calculated according to the four formulas,and 111 pairs of experimental samples meeting the CIELAB gray scale color difference requirements(1.0-14.0)were selected.Ten observers,aged between 22 and 27 with normal color vision,were participated in this study,using the gray scale method from psychophysical experiments to conduct color difference evaluations under the four light sources,with repeated experiments for each observer.The results indicated that the overall effect of the D65 light source on 3D objects color difference was minimal.In contrast,D50 and A light sources had a significant impact within the small color difference range,while the TL84 light source influenced both large and small color difference considerably.Among the four color difference formulas,CIEDE2000 demonstrated the best predictive performance for color difference in 3D objects,followed by CMC(1:1),CIE94,and CIELAB. 展开更多
关键词 Color difference formula 3D objects Light source Gray scale Normalized residual sum of squares
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Intra-annual variation in oak masting affects wildlife feeding behavior
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作者 Kelsey M.Demeny E.Hance Ellington +1 位作者 Kellie M.Kuhn Marcus A.Lashley 《Current Zoology》 2025年第1期79-88,共10页
Oaks(Quercus spp.)provide an important food source for many wildlife species throughout the fall and winter.Most research evaluating oak masting patterns and the subsequent behavioral responses of wildlife focuses on ... Oaks(Quercus spp.)provide an important food source for many wildlife species throughout the fall and winter.Most research evaluating oak masting patterns and the subsequent behavioral responses of wildlife focuses on the annual temporal scale.However,patterns in masting at the seasonal temporal scale may be important for wildlife behavior.We designed a study quantifying seasonal oak masting patterns of 3 oak species(water oak,Q.nigra;laurel oak,Q.laurifolia;and swamp chestnut oak,Q.michauxii)and linking those patterns to visitation and feeding behavior of 3 primary consumers(white-tailed deer,Odocoileus virginianus;gray squirrel,Sciurus carolinensis;and raccoon,Procyon lotor).We used seed traps to monitor the seasonal masting pattern of 205 trees in the fall of 2021 and 2022 and used camera traps concurrently to monitor wildlife behavior associated with a subset of 30 trees.Seasonal masting patterns differed between oak species both within a season and across years,and the timing of mast varied within oak species across years.White-tailed deer tended to visit swamp chestnut oak as the number of acorns increased and consumed their acorns.Gray squirrels and raccoons tended to visit laurel oak and consume water oak acorns with gray squirrels being more likely to consume as the number of acorns increased.Our results indicate that evaluating acorn production at multiple temporal scales may be necessary to fully understand oak masting relationships with wildlife.Furthermore,differences in wildlife behavior based on oak species may have important implications for oak regeneration. 展开更多
关键词 ACORNS anthropogenic subsidies gray squirrel QUERCUS RACCOON white-tailed deer
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Application of Gray Scale Method of Melanin Production in Zebrafish
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作者 Zheng Muchuang Xu Qitian +1 位作者 Ma Manhua Lei Cuiting 《China Detergent & Cosmetics》 2025年第3期47-52,共6页
Because the physiological characteristics and melanin regulation mechanism of zebrafish are highly similar with those of humans,it is of high reference value to use zebrafish model in the evaluation of cosmetic whiten... Because the physiological characteristics and melanin regulation mechanism of zebrafish are highly similar with those of humans,it is of high reference value to use zebrafish model in the evaluation of cosmetic whitening efficacy.In this study,zebrafish embryos are used as biological models to evaluate the whitening efficacy of six kinds of cosmetics raw materials,such as antioxidant,preservative and essence,and the formula of facial cleanser and facial mask products,and the limitations of the zebrafish melanin production grayscale detection method in practical application are discussed.The results show that the selection of different types of components can also reduce the production of melanin and show whitening effect.It can be seen that the gray scale method of melanin production in zebrafish is suitable for the evaluation of the efficacy of raw materials.In practical application,due to the complexity of the formula,the toxic effects of different types of ingredients may interfere with the melanin generation of zebrafish,affecting the judgment and evaluation of whitening efficacy.For the detection of whitening efficacy of products,a comprehensive evaluation system should be built together with other methods to accurately evaluate the whitening efficacy. 展开更多
关键词 zebrafish model skin whitening gray scale method MELANIN
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Gray zone and the need for expansion in chronic hepatitis B:From theory to clinical practice
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作者 Thang Viet Luong Ngoc Phan Hong Nguyen +3 位作者 Tri Van Nguyen Duong Hung Tran Thien Dinh Nguyen Hai Nguyen Ngoc Dang 《World Journal of Hepatology》 2025年第10期154-164,共11页
Chronic hepatitis B(CHB)remains a significant global health challenge.The natural course of CHB is traditionally divided into four phases:(1)Immune tolerance;(2)Immune activation;(3)Immune control;and(4)Immune escape.... Chronic hepatitis B(CHB)remains a significant global health challenge.The natural course of CHB is traditionally divided into four phases:(1)Immune tolerance;(2)Immune activation;(3)Immune control;and(4)Immune escape.However,approximately 20%-30%of patients referred to as the"gray zone"(GZ)do not fit neatly into these categories.These patients often exhibit elevated hepatitis B virus DNA levels alongside normal or mildly elevated alanine aminotransferase levels,placing them at significant risk for liver fibrosis,cirrhosis,and hepatocellular carcinoma.However,current clinical guidelines generally do not recommend antiviral therapy for GZ patients,increasing their vulnerability to adverse outcomes.This mini-review explores the challenges and gaps in CHB management,focusing on GZ patients.It also highlights recent advancements in therapeutic strategies and updates in clinical guidelines,emphasizing the need for a more inclusive,risk-adapted approach to treatment.By leveraging novel biomarkers,noninvasive fibrosis assessment tools,and artificial intelligencedriven predictive models,this article advocates for early intervention to mitigate disease progression and improve clinical outcomes in this overlooked population. 展开更多
关键词 Chronic hepatitis B Gray zone Antiviral therapy Biomarkers Risk stratification Liver fibrosis
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Link of gray matter volume to cognitive and motor function in elderly patients with mild cognitive impairment
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作者 Yue-Bing Yue Man-Fei Xu +3 位作者 Zheng Xu Jian-Xia Xu Min Lin Yi Yang 《World Journal of Psychiatry》 2025年第4期51-59,共9页
BACKGROUND Mild cognitive impairment(MCI)is a transitional state between normal aging and Alzheimer's disease(AD),characterized by subtle cognitive decline.Amnestic MCI(aMCI),in particular,is a critical precursor ... BACKGROUND Mild cognitive impairment(MCI)is a transitional state between normal aging and Alzheimer's disease(AD),characterized by subtle cognitive decline.Amnestic MCI(aMCI),in particular,is a critical precursor often progressing to AD.There is growing interest in understanding the neuroanatomical correlates of aMCI,especially the role of gray matter volume(GMV)in cognitive and motor function decline.This study hypothesized that aMCI patients will exhibit reduced GMV,particularly in brain regions associated with cognition and motor control,impacting both cognitive performance and motor abilities.AIM To investigate the association of GMV with cognitive and motor functions in aMCI.METHODS In this cross-sectional study conducted from March 2022 to March 2024,45 aMCI patients and 45 normal controls from our Department of Geratology were enrolled.Voxel-based morphometry was used to compare GMV between groups.Correlation of differential GMV with cognitive scores and gait parameters was assessed via partial correlation analysis.Linear regression was used to assess associations between whole-brain GMV and gait measures.RESULTS GMV of aMCI region of interest(ROI)1 and ROI2 was negatively correlated with Activities of Daily Living(ADL)score.GMV of ROI6 was positively correlated with the total scores of Mini-Mental State Examination and Cambridge Cognitive Examination-Chinese Version(CAMCOG-C)and negatively correlated with ADL score.In the partial correlation analysis of cognitive and motor function parameters,age,gender,educational level,height,and weight were controlled,and the results showed that CAMCOG-C was negatively correlated with Dual Task of Time Up and Go Test(TUG)duration in the aMCI group.The volume of the left occipital gray matter in the aMCI group was negatively correlated with TUG.GMV of the bilateral frontal gyrus,right orbitofrontal gyrus,right occipital cleft,right supraoccipital gyrus,and left anterior central gyrus was positively correlated with walking speed.CONCLUSION GMV reduction in aMCI correlates with impaired cognition and motor function,emphasizing key roles for prefrontal,occipital,and central regions in gait disorders. 展开更多
关键词 Amnestic mild cognitive impairment Gray matter volume Voxel-based morphometry Alzheimer's disease Motor function
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Structural brain correlates of neuropsychomotor performance in older adults with early cognitive decline
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作者 Haewon Byeon 《World Journal of Psychiatry》 2025年第10期409-416,共8页
This letter critically evaluates the study by Yue et al investigating the association between gray matter volume(GMV)and cognitive/motor function in amnestic mild cognitive impairment(aMCI).Yue et al utilized voxel-ba... This letter critically evaluates the study by Yue et al investigating the association between gray matter volume(GMV)and cognitive/motor function in amnestic mild cognitive impairment(aMCI).Yue et al utilized voxel-based morphometry(VBM)and comprehensive functional assessments,finding significant GMV reductions in aMCI patients compared to controls,notably in temporal,parietal,occipital,and frontal regions.These structural changes correlated significantly with lower cognitive scores(mini-metal state examination,cambridge cognitive examination-Chinese version,activities of daily living)and impaired gait parameters(timed up and go test,dual task timed up and go test,speed).While strengths include the use of VBM and combined cognitive-motor assessment,the study's cross-sectional design precludes causal inferences.The reliance on laboratory-based gait analysis may also limit ecological validity.The findings support the potential role of GMV as an aMCI biomarker and highlight the concept of shared neural substrates for cognitive and motor control.Future longitudinal,multi-modal imaging,and mechanistic studies are crucial to confirm causality,understand underlying pathways,and guide the development of integrated interventions for aMCI. 展开更多
关键词 Gray matter volume Amnestic mild cognitive impairment Voxel-based morphometry Cognitive-motor function Gait analysis BIOMARKER
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有限非链环F_(q)[u,v]/上的斜常循环码
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作者 姚婷 《阜阳师范大学学报(自然科学版)》 2025年第1期1-7,共7页
定义了一个新的Gray映射,讨论了环R上的线性码及Gray像。基于剩余定理,文章研究了环R上斜常循环码的结构性质,确定了斜常循环码的生成多项式,并给出了其对偶码的生成多项式。此外,文章确定了环R上常循环码的幂等生成元。
关键词 斜常循环码 生成多项式 Gray像 对偶码
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Gray Fabric Defect Detection Based on Statistical Template Matching
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作者 LI Saisai YU Haiyan WANG Junhua 《Journal of Donghua University(English Edition)》 2025年第6期594-605,共12页
To address the high cost of online detection equipment and the low adaptability and accuracy of online detection models that are caused by uneven lighting,high noise,low contrast and so on,a block-based template match... To address the high cost of online detection equipment and the low adaptability and accuracy of online detection models that are caused by uneven lighting,high noise,low contrast and so on,a block-based template matching method incorporating fabric texture characteristics is proposed.Firstly,the template image set is evenly divided into N groups of sub-templates at the same positions to mitigate the effects of image illumination,reduce the model computation,and enhance the detection speed,with all image blocks being preprocessed.Then,the feature value information is extracted from the processed set of subtemplates at the same position,extracting two gray-level cooccurrence matrix(GLCM)feature values for each image block.These two feature values are then fused to construct a matching template.The mean feature value of all image blocks at the same position is calculated and used as the threshold for template detection,enabling automatic selection of template thresholds for different positions.Finally,the feature values of the image blocks in the experimental set are traversed and matched with subtemplates at the same positions to obtain fabric defect detection results.The detection experiments are conducted on a platform that simulates a fabric weaving environment,using defective gray fabrics from a weaving factory as the detected objects.The outcomes demonstrate the efficacy of the proposed method in detecting defects in gray fabrics,the mitigation of the impact of uneven external lighting on detection outcomes,and the enhancement of detection accuracy and adaptability. 展开更多
关键词 defect detection gray-level co-occurrence matrix(GLCM) template matching gray fabric feature extraction online detection
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基于Gray—FAHP数学模型的我国农村金融风险评价体系研究
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作者 李香彬 《现代营销(下)》 2025年第4期22-24,共3页
如今,乡村振兴战略正紧锣密鼓地实施,而农村金融在现代农村经济中扮演着越来越重要的角色。农村金融在高速发展的同时又存在着许多风险,合适的金融风险评价方法可以对金融起到很好的监督预警作用。本文运用Gray—FAHP数学模型,从定性、... 如今,乡村振兴战略正紧锣密鼓地实施,而农村金融在现代农村经济中扮演着越来越重要的角色。农村金融在高速发展的同时又存在着许多风险,合适的金融风险评价方法可以对金融起到很好的监督预警作用。本文运用Gray—FAHP数学模型,从定性、定量的角度进行综合研判分析,建立多维评估指标体系,分析指标间的权重关系,揭示指标对农村金融安全性的内在影响,以达到对农村金融风险更加准确更加深刻的认知。为政府以及政策的制定者提供合理科学的数据支持,弥补农村金融安全性方面的不足,助力农村经济的安全、快速发展。 展开更多
关键词 Gray—FAHP 农村金融 风险评价 定量分析
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Grey-box modelling for estimation of optimum cut point temperature of crude distillation column
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作者 Junaid Shahzad Iftikhar Ahmad +5 位作者 Muhammad Ahsan Farooq Ahmad Husnain Saghir Manabu Kano Hakan Caliskan Hiki Hong 《CAAI Transactions on Intelligence Technology》 2025年第1期160-174,共15页
A grey-box modelling framework was developed for the estimation of cut point temperature of a crude distillation unit(CDU)under uncertainty in crude composition and process conditions.First principle(FP)model of CDU w... A grey-box modelling framework was developed for the estimation of cut point temperature of a crude distillation unit(CDU)under uncertainty in crude composition and process conditions.First principle(FP)model of CDU was developed for Pakistani crudes from Zamzama and Kunnar fields.A hybrid methodology based on the integration of Taguchi method and genetic algorithm(GA)was employed to estimate the optimal cut point temperature for various sets of process variables.Optimised datasets were utilised to develop an artificial neural networks(ANN)model for the prediction of optimum values of cut points.The ANN model was then used to replace the hybrid framework of the Taguchi method and the GA.The integration of the ANN and FP model makes it a grey-box(GB)model.For the case of Zamama crude,the GB model helped in the decrease of up to 38.93%in energy required per kilo barrel of diesel and an 8.2%increase in diesel production compared to the stand-alone FP model under uncertainty.Similarly,for Kunnar crude,up to 18.87%decrease in energy required per kilo barrel of diesel and a 33.96%increase in diesel production was observed in comparison to the stand-alone FP model. 展开更多
关键词 artificial neural networks crude distillation unit cut point temperature optimization exergy analysis gray box model industry 4.0
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两类周期为pq的四元序列在F_(4)上的线性复杂度
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作者 颜霏霏 柯品惠 《数学杂志》 2025年第2期151-160,共10页
本文研究了两类周期为pq的四元序列在F_(4)上的线性复杂度和极小多项式.利用[10,12]中的方法,证明了这两类序列在F_(4)上具有高的线性复杂度,从而可以抵抗Berlekamp-Massey算法的攻击.
关键词 逆Gray映射 广义分圆 四元序列 线性复杂度
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Gray relational analysis and SBOA-BP for predicting settlement intervals of high-speed railway subgrade
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作者 Quanpeng He Shaoyuan Li 《Railway Sciences》 2025年第2期199-212,共14页
Purpose–The deformation of the roadbed is easily influenced by the external environment to improve the accuracy of high-speed railway subgrade settlement prediction.Design/methodology/approach–A high-speed railway s... Purpose–The deformation of the roadbed is easily influenced by the external environment to improve the accuracy of high-speed railway subgrade settlement prediction.Design/methodology/approach–A high-speed railway subgrade settlement interval prediction method using the secretary bird optimization(SBOA)algorithm to optimize the BP neural network under the premise of gray relational analysis is proposed.Findings–Using the SBOA algorithm to optimize the BP neural network,the optimal weights and thresholds are obtained,and the best parameter prediction model is combined.The data were collected from the sensors deployed through the subgrade settlement monitoring system,and the gray relational analysis is used to verify that all four influencing factors had a great correlation to the subgrade settlement,and the collected data are verified using the model.Originality/value–The experimental results show that the SBOA-BP model has higher prediction accuracy than the BP model,and the SBOA-BP model has a wider range of prediction intervals for a given confidence level,which can provide higher guiding value for practical engineering applications. 展开更多
关键词 Gray relational analysis Secretary bird optimization algorithm Backpropagation neural network Subgrade settlement Interval prediction
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Fabrication and performance of embedded matrix indium thermal interface materials for advanced FCBGA packaging
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作者 WEN Jing SUN Guo-liao +5 位作者 WANG He-xin FAN Yi YI Ming-ming CHEN Zhuo WANG Lian-cheng ZHU Wen-hui 《Journal of Central South University》 2025年第10期3820-3833,共14页
Indium(In)has been used as a thermal interface material(TIM1)in high-performance central processing unit(CPU)for better heat dissipation.However,leakage or pump-out of liquid indium during the multiple reflow cycles l... Indium(In)has been used as a thermal interface material(TIM1)in high-performance central processing unit(CPU)for better heat dissipation.However,leakage or pump-out of liquid indium during the multiple reflow cycles limits its application in advanced flip chip ball gray array(FCBGA)packaging.Former researchers place a seal or dam structure to prevent In leakage,leading to the risk of In explosion,thermal degradation,or require additional keep-out zones.In this work,a copper foam(CF)matrix was embedded in In to absorb the liquid In and eliminate the leakage of In TIM1 during the multiple reflow cycles,as the CF capillary force.Au/Ni/Cu-Au/Ni/Cu joint was fabricated by soldering with the composite solder at 190℃for 2 min.After reflow cycles,good metallurgical bonding was formed at interfaces of joint.Rod-like Cu_(11)In_(9) formed at the CF and In interface,due to the re-dissolved of Cu_(11)In_(9) crystal.Small amount of Cu atoms from CF can reduce the activity of In,which inhibits the growth of Ni_(3)In_(7) intermetallic compound(IMC)at the interface of In and Au/Ni/Cu substrate.The CF matrix also improved the shear strength(22.9%)and thermal conductivity of the solder joints.Besides,the fracture behavior of solder joints without CF matrix was classified to be ductile type while that with CF matrix was changed to be ductile-brittle mixed type. 展开更多
关键词 INDIUM TIM1 LEAKAGE flip chip ball gray array copper foam matrix mechanical and thermal performance
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Physics-Guided Neural Network with Gini Impurity-Based Structural Optimizer for Prediction of Membrane-Type Acoustic Material Transmission Loss
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作者 PAN Xinrong LIU Xuewen +1 位作者 ZHU Bo WANG Yingyi 《Journal of Shanghai Jiaotong university(Science)》 2025年第3期612-624,共13页
With the rapid development of machine learning,the prediction of the performance of acoustic meta-materials using neural networks is replacing the traditional experiment-based testing methods.In this paper,a Gini impu... With the rapid development of machine learning,the prediction of the performance of acoustic meta-materials using neural networks is replacing the traditional experiment-based testing methods.In this paper,a Gini impurity-based artificial neural network structural optimizer(GIASO)is proposed to optimize the neural network structure,and the effects of five different initialization algorithms on the model performance and struc-ture optimization are investigated.Two physically guided models with additional resonant frequencies and sound transmission loss formula are achieved to further improve the prediction accuracy of the model.The results show that GIASO utilizing the gray wolf optimizer as the initialization method can significantly improve the prediction performance of the model.Simultaneously,the physical guidance model with additional resonant frequencies has the best performance and can better predict the edge data points.Eventually,the effect of each input parameter on the sound transmission loss is explained by combining sensitivity analysis and theoretical formulation. 展开更多
关键词 membrane-type acoustic metamaterial sound transmission loss eigenfrequency physics-guided neu-ral network architecture search Gini impurity gray wolf optimizer initial methods
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