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A Cognitive Psychological Study on the Acquisition of Chinese Word’s Coloring Meaning--Chinese as a Second Language
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作者 LIU Yan 《Sino-US English Teaching》 2024年第5期217-221,共5页
Lexical meaning mainly includes rational meaning,grammatical meaning,and coloring meaning.Mastering the coloring meaning of vocabulary is of great significance for foreign students to use Chinese vocabulary correctly.... Lexical meaning mainly includes rational meaning,grammatical meaning,and coloring meaning.Mastering the coloring meaning of vocabulary is of great significance for foreign students to use Chinese vocabulary correctly.This study mainly examines the psychological mechanism of Chinese second language learners mastering the coloring meaning of words,examines the psychological characteristics of students mastering the color meaning of words from the perspectives of second language learning theory and cognitive theory,establishes a cognitive schema for coloring meaning learning,and proposes corresponding learning models and teaching strategies. 展开更多
关键词 Chinese vocabulary acquisition coloring meaning COGNITION
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Exploring the meaning of care among lived experiences of patients with blindness:an interpretive phenomenological study
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作者 Mohammad Ali Mohammadi Mehdi Heidarzadeh +1 位作者 Saeed Mehri Mahmood Shamshiri 《Frontiers of Nursing》 2024年第3期319-326,共8页
Objective:To explore the meaning of care experienced by people with blindness in hospitals.Methods:Interpretive phenomenology along with the 6-step method of van Manen was used to conduct the study.Using purposeful sa... Objective:To explore the meaning of care experienced by people with blindness in hospitals.Methods:Interpretive phenomenology along with the 6-step method of van Manen was used to conduct the study.Using purposeful sampling,15 people with legal blindness were interviewed.Thematic analysis was used to isolate the meaning of care.Results:Five themes emerged:(a)nurses in the eyes of patients with blindness;(b)negligence in the caring moments;(c)being cared for in ambiguity;(d)Uncoordinated care;and(e)Psychological discomfor t.These sub-themes were condensed into an overarching theme titled as“marginalized patients inside the stereotypical healthcare system.”Conclusions:Lived experiences of patients with blindness revealed that hospitals provide stereotypic or inappropriate care for this minority group in society.Health professionals par ticularly nurses should be skilled to provide person-centered and coordinated care for patients with blindness. 展开更多
关键词 HOSPITALIZATION lived experience meaning of care people with blindness PHENOMENOLOGY
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Lossless embedding: A visually meaningful image encryption algorithm based on hyperchaos and compressive sensing 被引量:1
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作者 王兴元 王哓丽 +2 位作者 滕琳 蒋东华 咸永锦 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期136-149,共14页
A novel visually meaningful image encryption algorithm is proposed based on a hyperchaotic system and compressive sensing(CS), which aims to improve the visual security of steganographic image and decrypted quality. F... A novel visually meaningful image encryption algorithm is proposed based on a hyperchaotic system and compressive sensing(CS), which aims to improve the visual security of steganographic image and decrypted quality. First, a dynamic spiral block scrambling is designed to encrypt the sparse matrix generated by performing discrete wavelet transform(DWT)on the plain image. Then, the encrypted image is compressed and quantified to obtain the noise-like cipher image. Then the cipher image is embedded into the alpha channel of the carrier image in portable network graphics(PNG) format to generate the visually meaningful steganographic image. In our scheme, the hyperchaotic Lorenz system controlled by the hash value of plain image is utilized to construct the scrambling matrix, the measurement matrix and the embedding matrix to achieve higher security. In addition, compared with other existing encryption algorithms, the proposed PNG-based embedding method can blindly extract the cipher image, thus effectively reducing the transmission cost and storage space. Finally, the experimental results indicate that the proposed encryption algorithm has very high visual security. 展开更多
关键词 chaotic image encryption compressive sensing meaningful cipher image portable network graphics image encryption algorithm
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Meaning in Life and Mental Health Issues in Older Adults:A Meta-Analysis
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作者 Shu Nie Jiyoon Lim +2 位作者 Xintian Xu Lei Zheng Yiqun Gan 《International Journal of Mental Health Promotion》 2023年第9期971-984,共14页
This study aims to be the first to use meta-analysis to explore the relationship between meaning in life(MIL)and mental health issues among older adults.A meta-analysis was conducted using six databases,resulting in 1... This study aims to be the first to use meta-analysis to explore the relationship between meaning in life(MIL)and mental health issues among older adults.A meta-analysis was conducted using six databases,resulting in 16 studies with 5,074 participants in total.The“metacor”and“forestplot”packages in R-Studio were used for data analysis.The total effect was calculated using a random-effects model,with I2=86%in the heterogeneity test.The results showed a moderate negative correlation between MIL and mental health issues among older adults,with an average effect of−0.37.Five potential moderating variables were examined:the conceptualization of MIL(value vs.purpose),region(Asian vs.Western countries),residence status(community vs.nursing home vs.hospital),types of mental health issues,and evaluation methods(clinical vs.non-clinical).The first four had no significant moderating effect.The mean correlation coefficients between mental health issues and value/purpose were−0.49/−0.33;the mean correlation coefficients in Asian countries and Western countries were−0.48 and−0.34;the mean correlation coefficients among participants living in community/nursing home/mixed status were−0.33/−0.40/−0.40;the mean correlation coefficients between MIL and depression/others were−0.37/−0.35;however,the negative relationship between MIL and mental health issues was stronger when non-clinical evaluations(self-report only)were used.Specifically,the mean correlation coefficient for non-clinical evaluations was−0.42 and for clinical evaluations was−0.29.This study is the first meta-analysis to identify the negative correlation between older adults’MIL and mental health issues.Significant moderating effects of evaluation methods were found. 展开更多
关键词 meaning in life mental health issues DEPRESSION ANXIETY META-ANALYSIS older adults
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Visually meaningful image encryption algorithm based on digital signature
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作者 Xiaoling Huang Youxia Dong +2 位作者 Guodong Ye Wun-She Yap Bok-Min Goi 《Digital Communications and Networks》 SCIE CSCD 2023年第1期159-165,共7页
Traditional image encryption algorithms transform a plain image into a noise-like image.To lower the chances for the encrypted image being detected by the attacker during the image transmission,a visually meaningful i... Traditional image encryption algorithms transform a plain image into a noise-like image.To lower the chances for the encrypted image being detected by the attacker during the image transmission,a visually meaningful image encryption scheme is suggested to hide the encrypted image using another carrier image.This paper proposes a visually meaningful encrypted image algorithm that hides a secret image and a digital signature which provides authenticity and confidentiality.The recovered digital signature is used for the purpose of identity authentication while the secret image is encrypted to protect its confidentiality.Least Significant Bit(LSB)method to embed signature on the encrypted image and Lifting Wavelet Transform(LWT)to generate a visually meaningful encrypted image are designed.The proposed algorithm has a keyspace of 139.5-bit,a Normalized Correlation(NC)value of 0.9998 which is closer to 1 and a Peak Signal to Noise Ratio(PSNR)with a value greater than 50 dB.Different analyses are also performed on the proposed algorithm using different images.The experimental results show that the proposed scheme is with high key sensitivity and strong robustness against pepper and salt attack and cropping attack.Moreover,the histogram analysis shows that the original carrier image and the final visual image are very similar. 展开更多
关键词 Visually meaningful image encryption Lifting wavelet transform Lorenz system SIGNATURE SECURITY
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Analysis of the Symbolic Meaning of James Joyce’s Araby
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作者 SUN Qiu-yue 《Journal of Literature and Art Studies》 2023年第3期160-164,共5页
Araby is a short story by the famous Irish stream-of-consciousness writer James Joyce.Through a series of images,the novel expresses the theme of the story:the“mental paralysis”of Dubliners and the“spiritual Epiph... Araby is a short story by the famous Irish stream-of-consciousness writer James Joyce.Through a series of images,the novel expresses the theme of the story:the“mental paralysis”of Dubliners and the“spiritual Epiphany”of the little boy,which reflects the spiritual barren of Dubliners at that time.Through the analysis of the symbolic meaning of many images in the work,this paper reveals the social background and religious significance hidden behind the images. 展开更多
关键词 symbolic meaning James Joyce ARABY
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The Comparative Study of Chuangtse’s English Translations Under the Theory of Spirit Transmission and Meaning Conveyance
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作者 QIN Xiaowan PENG Keming 《Cultural and Religious Studies》 2023年第4期183-186,共4页
Cultural-loaded word is one of the most popular topics in translation studies.The theory of spirit transmission and meaning conveyance provides a new way for the translation of cultural-loaded word.Based on the A Happ... Cultural-loaded word is one of the most popular topics in translation studies.The theory of spirit transmission and meaning conveyance provides a new way for the translation of cultural-loaded word.Based on the A Happy Excursion,this paper makes a comparative analysis of the translation strategies of seven English versions.This study will reveal the similarities and differences between Chinese and foreign translators’translation strategies. 展开更多
关键词 Chuangtse spirit transmission and meaning conveyance comparative study
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An Exploratory Study of the Interpersonal Meanings of President Xi’s New Year Speech Based on Appraisal Theory
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作者 LIN Hanzhao 《Cultural and Religious Studies》 2023年第2期84-90,共7页
The research examines President Xi’s 2021 New Year speech with research questions centering around its abundant interpersonal meanings.Through qualitative content analysis,the research finds that it is typical for Ch... The research examines President Xi’s 2021 New Year speech with research questions centering around its abundant interpersonal meanings.Through qualitative content analysis,the research finds that it is typical for Chinese president to frequently use judgment and appreciation resources in reviewing the past year.Even in the face of the pandemic and natural disasters,the overall emotions of the speech remain positive,which corresponds to the forward-looking feature of New Year speech.Significance of the study abounds and future research can investigate how COVID-19 impacts the ideologies conveyed through political leaders’speeches through a comparative lens and how to produce more understandings that can help dismantle stereotypes and discrimination hidden in reports about COVID-19 by using Appraisal Theory critically,systematically,and comprehensively. 展开更多
关键词 Political discourse New Year speech Appraisal Theory Interpersonal meanings COVID-19 pandemic
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融合IMR-WGAN的时序数据修复方法 被引量:1
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作者 孟祥福 马荣国 《小型微型计算机系统》 CSCD 北大核心 2024年第3期641-650,共10页
工业数据由于技术故障和人为因素通常导致数据异常,现有基于约束的方法因约束阈值设置的过于宽松或严格会导致修复错误,基于统计的方法因平滑修复机制导致对时间步长较远的异常值修复准确度较低.针对上述问题,提出了基于奖励机制的最小... 工业数据由于技术故障和人为因素通常导致数据异常,现有基于约束的方法因约束阈值设置的过于宽松或严格会导致修复错误,基于统计的方法因平滑修复机制导致对时间步长较远的异常值修复准确度较低.针对上述问题,提出了基于奖励机制的最小迭代修复和改进WGAN混合模型的时序数据修复方法.首先,在预处理阶段,保留异常数据,进行信息标注等处理,从而充分挖掘异常值与真实值之间的特征约束.其次,在噪声模块提出了近邻参数裁剪规则,用于修正最小迭代修复公式生成的噪声向量.将其传递至模拟分布模块的生成器中,同时设计了一个动态时间注意力网络层,用于提取时序特征权重并与门控循环单元串联组合捕捉不同步长的特征依赖,并引入递归多步预测原理共同提升模型的表达能力;在判别器中设计了Abnormal and Truth奖励机制和Weighted Mean Square Error损失函数共同反向优化生成器修复数据的细节和质量.最后,在公开数据集和真实数据集上的实验结果表明,该方法的修复准确度与模型稳定性显著优于现有方法. 展开更多
关键词 数据修复 改进Wasserstein生成对抗网络 Abnormal and Truth奖励机制 动态时间注意力机制 Weighted Mean Square Error损失函数
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转录组和代谢组联合分析阐释木薯叶片花青素合成机制
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作者 罗秀芹 韦卓文 +3 位作者 蔡杰 安飞飞 陈松笔 薛晶晶 《中国农学通报》 2024年第24期100-106,共7页
木薯是世界上第六大粮食作物,其块根富含淀粉但缺乏蛋白质、花青素、胡萝卜素等营养物质。为了探索木薯花青素生物合成机制,本研究选取了两种不同颜色木薯种质资源叶片(FL与PL)为材料,进行转录组和花青素靶向代谢组及其联合分析。转录... 木薯是世界上第六大粮食作物,其块根富含淀粉但缺乏蛋白质、花青素、胡萝卜素等营养物质。为了探索木薯花青素生物合成机制,本研究选取了两种不同颜色木薯种质资源叶片(FL与PL)为材料,进行转录组和花青素靶向代谢组及其联合分析。转录组分析结果显示在FL和PL中6864个差异表达基因,其中包含4112个上调表达和2752个下调表达。代谢组分析结果显示26种显著差异代谢物在PL中显著高于FL,其中21种属于花青素类。联合分析结果显示,其中7个差异表达的基因与花青素生物合成相关,且花青素含量与差异基因的表达呈正相关,尤其是MeANS1的表达差异最大。本研究结果为阐明木薯花青素的生物合成机制提供了候选基因,同时也为提高木薯花青素含量奠定科学基础。 展开更多
关键词 木薯 类黄酮 花青素 转录组 代谢组 生物合成 差异表达基因 MeANS
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Mean Shift跟踪算法创新实验项目设计
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作者 王辉 王雪莹 于立君 《实验室科学》 2024年第1期12-16,共5页
视频跟踪算法是计算机视觉实践课程中比较受关注的实验项目。针对突变情况下传统Mean Shift跟踪算法无法实时准确跟踪的问题,设计了基于模板更新和线性预估的Mean Shift跟踪算法创新实验项目。在模板更新策略下,引入背景模板,通过将原... 视频跟踪算法是计算机视觉实践课程中比较受关注的实验项目。针对突变情况下传统Mean Shift跟踪算法无法实时准确跟踪的问题,设计了基于模板更新和线性预估的Mean Shift跟踪算法创新实验项目。在模板更新策略下,引入背景模板,通过将原目标模板和背景模板与设定的阈值进行比较来对干扰因素进行判定,当干扰因素判定目标受到遮挡时,引入线性预估方程进行目标位置预测,有效解决目标在遮挡情况下跟踪丢失的问题。通过对测试视频的跟踪效果和性能进行对比分析,验证了算法在突变情况下相较于传统算法具有更好的抗干扰能力。以算法创新设计为核心,通过开放性创新实验项目的选题、设计、答辩、反馈的闭环实验过程,有效提高了学生算法创新设计能力。 展开更多
关键词 Mean Shift跟踪算法 模板更新 线性预估 抗干扰
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基于深度对比学习的文本聚类
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作者 胥桂仙 李晓荣 《中央民族大学学报(自然科学版)》 2024年第3期62-72,共11页
无监督聚类的目的是根据表示空间中的距离将数据划分为有意义或有用的簇,但往往不同类别在表示空间中是相互重叠的,为了实现不同类别的良好分离,使用实例对比学习模型,修改模型的激活函数为Tanh,并将单层感知机修改为多层感知机,提出了... 无监督聚类的目的是根据表示空间中的距离将数据划分为有意义或有用的簇,但往往不同类别在表示空间中是相互重叠的,为了实现不同类别的良好分离,使用实例对比学习模型,修改模型的激活函数为Tanh,并将单层感知机修改为多层感知机,提出了深度对比学习聚类模型。模型首先将原始中文长文本数据集输入神经网络特征提取层BERT中,然后将提取到的全部特征输入实例对比学习层中,对特征进行优化,最终使用K⁃means进行聚类。深度对比学习聚类模型在中文长文本聚类方面的性能相比于无监督聚类,在THUCNews数据集上的准确度提高了10%~25%。能够更好地促进不同类别相互重叠的数据的有效分离,实验效果显著优于现有的其他相关模型。 展开更多
关键词 实例对比学习模型 深度对比学习聚类模型 长文本聚类 K⁃means 实例对比学习层
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京津冀地区碳排放时空格局变化及其驱动因子 被引量:2
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作者 陈靖松 张建军 +1 位作者 李金龙 李山 《生态学报》 CAS CSCD 北大核心 2024年第6期2270-2283,共14页
人类对陆地生态系统的改变是碳排放增加的主要原因。在“双碳”目标背景下探索土地利用变化与碳排放的动态关系,有助于区域土地低碳可持续利用。研究基于土地利用转移视角,采用重心-标准差椭圆方法揭示了京津冀地区土地利用碳排放时空... 人类对陆地生态系统的改变是碳排放增加的主要原因。在“双碳”目标背景下探索土地利用变化与碳排放的动态关系,有助于区域土地低碳可持续利用。研究基于土地利用转移视角,采用重心-标准差椭圆方法揭示了京津冀地区土地利用碳排放时空格局演化特征,评估了碳排放与生态环境、社会经济发展的协调程度,并借助改进的Kaya模型和LMDI分解模型定量分析了土地利用变化对碳排放的影响程度。结果表明:(1)建设用地的转入是土地利用碳排放增加的主要来源,引起碳排放量增加15844.36万t;耕地、草地向林地、水域的转变促进了地区固碳能力的提升。(2)土地利用碳排放空间分布格局呈现出东北-西南方向向中心进一步聚集的趋势,并且东-西向聚集趋势大于南-北向。(3)京津冀地区整体碳排放与生态环境的协调性呈向好趋势发展,但大部分地区碳排放与社会经济发展出现失衡现象,地区间碳生产力差异逐渐增大。(4)经济水平是促进碳排放增加的最显著因素,单位GDP用地强度是抑制碳排放增加的最主要因素。分析结果表明,严格控制建设用地的无序扩张是促进低碳土地利用的基础,低碳经济发展是促进地区减碳的重要途径。 展开更多
关键词 城市群 土地利用 碳排放 Logarithmic Mean Divisia Index
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Record-breaking High-temperature Outlook for 2023: An Assessment Based on the China Global Merged Temperature(CMST) Dataset 被引量:3
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作者 Zichen LI Qingxiang LI Tianyi CHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期369-376,共8页
According to the latest version(version 2.0) of the China global Merged Surface Temperature(CMST2.0) dataset, the global mean surface temperature(GMST) in the first half of 2023 reached its third warmest value since t... According to the latest version(version 2.0) of the China global Merged Surface Temperature(CMST2.0) dataset, the global mean surface temperature(GMST) in the first half of 2023 reached its third warmest value since the period of instrumental observation began, being only slightly lower than the values recorded in 2016 and 2020, and historically record-breaking GMST emerged from May to July 2023. Further analysis also indicates that if the surface temperature in the last five months of 2023 approaches the average level of the past five years, the annual average surface temperature anomaly in 2023 of approximately 1.26°C will break the previous highest surface temperature, which was recorded in 2016of approximately 1.25°C(both values relative to the global pre-industrialization period, i.e., the average value from 1850 to1900). With El Ni?o triggering a record-breaking hottest July, record-breaking average annual temperatures will most likely become a reality in 2023. 展开更多
关键词 CMST2.0 global mean surface temperature record-breaking temperature El Ni?o
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El Niño and the AMO Sparked the Astonishingly Large Margin of Warming in the Global Mean Surface Temperature in 2023 被引量:2
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作者 Kexin LI Fei ZHENG +1 位作者 Jiang ZHU Qing-Cun ZENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1017-1022,共6页
In 2023,the majority of the Earth witnessed its warmest boreal summer and autumn since 1850.Whether 2023 will indeed turn out to be the warmest year on record and what caused the astonishingly large margin of warming ... In 2023,the majority of the Earth witnessed its warmest boreal summer and autumn since 1850.Whether 2023 will indeed turn out to be the warmest year on record and what caused the astonishingly large margin of warming has become one of the hottest topics in the scientific community and is closely connected to the future development of human society.We analyzed the monthly varying global mean surface temperature(GMST)in 2023 and found that the globe,the land,and the oceans in 2023 all exhibit extraordinary warming,which is distinct from any previous year in recorded history.Based on the GMST statistical ensemble prediction model developed at the Institute of Atmospheric Physics,the GMST in 2023 is predicted to be 1.41℃±0.07℃,which will certainly surpass that in 2016 as the warmest year since 1850,and is approaching the 1.5℃ global warming threshold.Compared to 2022,the GMST in 2023 will increase by 0.24℃,with 88%of the increment contributed by the annual variability as mostly affected by El Niño.Moreover,the multidecadal variability related to the Atlantic Multidecadal Oscillation(AMO)in 2023 also provided an important warming background for sparking the GMST rise.As a result,the GMST in 2023 is projected to be 1.15℃±0.07℃,with only a 0.02℃ increment,if the effects of natural variability—including El Niño and the AMO—are eliminated and only the global warming trend is considered. 展开更多
关键词 record-breaking temperature global mean surface temperature El Niño AMO global warming
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Genetics of biochemical attributes regulating morpho-physiology of upland cotton under high temperature conditions 被引量:1
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作者 MAJEED Sajid CHAUDHARY Muhammad Tanees +7 位作者 MUBARIK Muhammad Salman RANA Iqrar Ahmad SHABAN Muhammad TAN Daniel KY JIA Yinhua DU Xiongming HINZE Lori AZHAR Muhammad Tehseen 《Journal of Cotton Research》 CAS 2024年第1期29-44,共16页
Background Cotton is a strategically important fibre crop for global textile industry.It profoundly impacts several countries’industrial and agricultural sectors.Sustainable cotton production is continuously threaten... Background Cotton is a strategically important fibre crop for global textile industry.It profoundly impacts several countries’industrial and agricultural sectors.Sustainable cotton production is continuously threatened by the unpre-dictable changes in climate,specifically high temperatures.Breeding heat-tolerant,high-yielding cotton cultivars with wide adaptability to be grown in the regions with rising temperatures is one of the primary objectives of modern cotton breeding programmes.Therefore,the main objective of the current study is to figure out the effective breed-ing approach to imparting heat tolerance as well as the judicious utilization of commercially significant and stress-tolerant attributes in cotton breeding.Initially,the two most notable heat-susceptible(FH-115 and NIAB Kiran)and tolerant(IUB-13 and GH-Mubarak)cotton cultivars were spotted to develop filial and backcross populations to accom-plish the preceding study objectives.The heat tolerant cultivars were screened on the basis of various morphological(seed cotton yield per plant,ginning turnout percentage),physiological(pollen viability,cell membrane thermostabil-ity)and biochemical(peroxidase activity,proline content,hydrogen peroxide content)parameters.Results The results clearly exhibited that heat stress consequently had a detrimental impact on every studied plant trait,as revealed by the ability of crossing and their backcross populations to tolerate high temperatures.However,when considering overall yield,biochemical,and physiological traits,the IUB-13×FH-115 cross went over particularly well at both normal and high temperature conditions.Moreover,overall seed cotton yield per plant exhibited a posi-tive correlation with both pollen viability and antioxidant levels(POD activity and proline content).Conclusions Selection from segregation population and criteria involving pollen viability and antioxidant levels concluded to be an effective strategy for the screening of heat-tolerant cotton germplasms.Therefore,understanding acquired from this study can assist breeders identifying traits that should be prioritized in order to develop climate resilient cotton cultivars. 展开更多
关键词 ACCESSIONS BIOCHEMICAL BREEDING Cotton Generation mean analysis Heat stress
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Three-Dimensional Sound Source Location Algorithm for Subsea Leakage Using Hydrophone 被引量:1
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作者 LI Hao-jie CAI Bao-ping +6 位作者 YUAN Xiao-bing KONG Xiang-di LIU Yong-hong Javed Akbar KHAN CHU Zheng-de YANG Chao TANG An-bang 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期326-337,共12页
Leakages from subsea oil and gas equipment cause substantial economic losses and damage to marine ecosystem,so it is essential to locate the source of the leak.However,due to the complexity and variability of the mari... Leakages from subsea oil and gas equipment cause substantial economic losses and damage to marine ecosystem,so it is essential to locate the source of the leak.However,due to the complexity and variability of the marine environment,the signals collected by hydrophone contain a variety of noises,which makes it challenging to extract useful signals for localization.To solve this problem,a hydrophone denoising algorithm is proposed based on variational modal decomposition(VMD)with grey wolf optimization.First,the average envelope entropy is used as the fitness function of the grey wolf optimizer to find the optimal solution for the parameters K andα.Afterward,the VMD algorithm decomposes the original signal parameters to obtain the intrinsic mode functions(IMFs).Subsequently,the number of interrelationships between each IMF and the original signal was calculated,the threshold value was set,and the noise signal was removed to calculate the time difference using the valid signal obtained by reconstruction.Finally,the arrival time difference is used to locate the origin of the leak.The localization accuracy of the method in finding leaks is investigated experimentally by constructing a simulated leak test rig,and the effectiveness and feasibility of the method are verified. 展开更多
关键词 grey wolf optimizer variational modal decomposition mean envelope entropy correlation coefficient time difference of arrival
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Underwater four-quadrant dual-beam circumferential scanning laser fuze using nonlinear adaptive backscatter filter based on pauseable SAF-LMS algorithm 被引量:1
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作者 Guangbo Xu Bingting Zha +2 位作者 Hailu Yuan Zhen Zheng He Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第7期1-13,共13页
The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser fuzes.To overcome this issue,we propose a four-quadrant ... The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser fuzes.To overcome this issue,we propose a four-quadrant dual-beam circumferential scanning laser fuze to distinguish various interference signals and provide more real-time data for the backscatter filtering algorithm.This enhances the algorithm loading capability of the fuze.In order to address the problem of insufficient filtering capacity in existing linear backscatter filtering algorithms,we develop a nonlinear backscattering adaptive filter based on the spline adaptive filter least mean square(SAF-LMS)algorithm.We also designed an algorithm pause module to retain the original trend of the target echo peak,improving the time discrimination accuracy and anti-interference capability of the fuze.Finally,experiments are conducted with varying signal-to-noise ratios of the original underwater target echo signals.The experimental results show that the average signal-to-noise ratio before and after filtering can be improved by more than31 d B,with an increase of up to 76%in extreme detection distance. 展开更多
关键词 Laser fuze Underwater laser detection Backscatter adaptive filter Spline least mean square algorithm Nonlinear filtering algorithm
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基于信令数据的中型城市通勤公交站点优化方法
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作者 葛浩菁 吕远 焦朋朋 《交通信息与安全》 CSCD 北大核心 2024年第1期142-149,共8页
大中型城市之间的手机通信基站密度和通勤出行结构不同,公交站点布设呈现出显著差异。在此背景下,研究了基于改进Mean Shift聚类算法的中型城市通勤公交站点优化方法。该方法采用荆州市中心城区信令数据中的通勤记录,以系统总成本(包括... 大中型城市之间的手机通信基站密度和通勤出行结构不同,公交站点布设呈现出显著差异。在此背景下,研究了基于改进Mean Shift聚类算法的中型城市通勤公交站点优化方法。该方法采用荆州市中心城区信令数据中的通勤记录,以系统总成本(包括运营成本和乘客步行时间成本)作为主要评价指标。根据中心城区早高峰的通勤出行需求,制定通勤公交站点优化方案。通过对比优化结果和现有公交站点布局,验证了优化方法的有效性;比较不同聚类算法,证明改进的Mean Shift聚类算法的性能优越性;考虑基站和等时圈的影响,对比不同场景,证明了考虑二者影响的必要性。结果表明:①针对荆州市研究区域的早高峰出行需求,优化方法共设置28个公交站,乘客步行时间成本下降51.98%,系统总成本下降17.82%,表明本方法能够得到系统总成本更优的站点布设方案,有效减少研究区域内乘客步行时间成本;②与不同聚类算法的比较中,改进Mean Shift算法得到的方案有明显提升,系统总成本比K-means聚类算法下降8.73%,比近邻传播聚类算法(affinity propagation,AP)下降2.48%;③与未考虑基站和等时圈影响的情况相比,本算法步行时间成本有所下降。上述指标表明改进Mean Shift聚类方法在聚类质量上优于其他方法,可以获得更优的公交站点布设方案,为中型城市的公交线路规划提供基础。 展开更多
关键词 交通规划 中型城市 公交站点布设 改进Mean Shift算法 信令数据
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基于关联规则的粗纱工序断头影响因素分析
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作者 郑通 薛风洋 张立杰 《棉纺织技术》 CAS 2024年第6期22-26,共5页
为了降低粗纱在生产过程中的断头率,提高纱线生产质量和效率,通过生产实践收集纺制C 14.6 tex和JC 24.3 tex两个品种的粗纱工序断头影响因素。使用K⁃means聚类算法对影响因素指标分别进行聚类,然后使用Apriori算法将聚类后的断头影响因... 为了降低粗纱在生产过程中的断头率,提高纱线生产质量和效率,通过生产实践收集纺制C 14.6 tex和JC 24.3 tex两个品种的粗纱工序断头影响因素。使用K⁃means聚类算法对影响因素指标分别进行聚类,然后使用Apriori算法将聚类后的断头影响因素指标数据集进行关联规则挖掘。结果表明:纺制C 14.6 tex品种的粗纱工序断头影响因素关联规则有粗纱回潮率和末并定量湿重,粗纱条干CV和末并定量湿重,末并定量湿重和粗纱条干CV;纺制JC 24.3 tex品种的粗纱工序断头影响因素关联规则有粗纱捻系数和粗纱定量湿重,粗纱捻系数、粗纱条干CV和粗纱定量湿重,粗纱定量湿重和粗纱捻系数;当关联规则中的影响因素同时升高时,粗纱工序断头率增加。通过关联规则中挖掘出的信息,可为纺纱企业减少粗纱工序断头、提高纱线质量提供帮助。 展开更多
关键词 粗纱工序 断头影响因素 数据挖掘 K⁃means聚类 关联规则 APRIORI算法
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