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Analysis on the Degradation Causes of Bashang Inland Lake Wetland in Hebei Province 被引量:2
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作者 阳小兰 陈辉 +3 位作者 张茹春 王瑞君 高士平 蒋红军 《Agricultural Science & Technology》 CAS 2010年第7期87-90,共4页
The degeneration of Bashang inland lake wetland in Hebei Province is caused by both some natural reasons,such as temperature rises and violent pathogenic wind,and some human factors like the large increase of populati... The degeneration of Bashang inland lake wetland in Hebei Province is caused by both some natural reasons,such as temperature rises and violent pathogenic wind,and some human factors like the large increase of population and arable area,the production of season-staggered vegetable,which have increased the water utilization and made many lakes dry up completely or partly.Based on the degeneration reasons,the related measures for restoring the function of Bashang wetland ecosystem were proposed in this paper. 展开更多
关键词 Bashang wetland Wetland degeneration REASONS
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Research on Ecological Regionalization of Inland Lake Wetland of Bashang in Hebei Province 被引量:1
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作者 张茹春 阳小兰 +3 位作者 高士平 陈辉 王瑞君 蒋红军 《Agricultural Science & Technology》 CAS 2010年第8期125-128,144,共5页
An ecological regionalization index system was established for Bashang inland lake wetland based on ecological and environmental factors,with landform,geomorphy,vegetation types and climate as primary indices,micro-la... An ecological regionalization index system was established for Bashang inland lake wetland based on ecological and environmental factors,with landform,geomorphy,vegetation types and climate as primary indices,micro-landform,vegetation type,soil type,climate,ecosystem types,wetland features and human activities as secondary indices. Based on these index systems,the area was divided into three eco-environment regions and nine sub eco-environment regions. An eco-regional map of Bashang inland lake wetland was drawn by using GIS. The ecological characteristics,existing problems and control measures of each region were described. This study will supply guidance for the construction of local ecological environment and regulation of industrial structure,promoting sustainable development of Bashang inland lake wetland. 展开更多
关键词 Ecological regionalization ECO-ENVIRONMENT Bashang wetland
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Study on Pollen Morphology of Nine Major Crops in Bashang Plateau of Hebei Province
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作者 张茹春 阳小兰 +1 位作者 蒋红军 王瑞君 《Agricultural Science & Technology》 CAS 2013年第6期838-841,885,共5页
[Objective] This study aimed to investigate the pollen morphology of nine major crops in Bashang Plateau of Hebei Province. [Method] By using an optical microscope, pollen morphology of nine major crops in Bashang Pla... [Objective] This study aimed to investigate the pollen morphology of nine major crops in Bashang Plateau of Hebei Province. [Method] By using an optical microscope, pollen morphology of nine major crops in Bashang Plateau of Hebei Province was observed and compared. [Result] Pollen grains were spherical, nearly spherical or prolate; pollen grains of Cucurbita pepo were the largest, and those of Brassica campestris were the smallest; P/E value of Vicia faba was the maximum of 1.77, and that of Avena chinsis was the minimum of 1.00; there were six types of germinal apertures, including single-aperture, scattered-aperture, 3-aperture, 3-groove, 3-colporate and 3-4-colporate; there were four types of exine ornamentation, including reticulate ornamentation, warty ornamentation, spinulose ornamentation and granular ornamentation. [Conclusion] This study not only provided standard maps and related information for the identification of crop pollens in different strata, but also provided modern palynological evidence for extracting information of synarthropic plants (cultivated crops mostly) in different strata, deducing the natural environment ancient human lived in, and understanding the relationship between human and environmental changes. 展开更多
关键词 Pollen morphology CROPS Bashang Plateau
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Development of land desertification in Bashang area in the past 20 years 被引量:5
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作者 Chen Zhi-qing Zhu Zhen-da 《Journal of Geographical Sciences》 SCIE CSCD 2001年第4期53-57,共5页
Natural conditions in Bashang area are characterized by zonal transitions which are liable to be impacted by natural disasters and intensified human activities. The extremely fragile eco-environment is also liable to ... Natural conditions in Bashang area are characterized by zonal transitions which are liable to be impacted by natural disasters and intensified human activities. The extremely fragile eco-environment is also liable to have desertification formed and developed. In the 18 years from 1978 to 1996, the desertified land area of Bashang within the scope of the map nearly doubled, a total increase of 2199.11 km2, averaging an increase of 122.17 km2 per year. Moreover, the seriously desertified area increases rapidly. Land desertification in Bashang is the combined result of natural factors and irrational human economic activities. Cultivated land expansion, population growth, and overgrazing aggrevate desertification development. 展开更多
关键词 Bashang area DESERTIFICATION impact of human activities
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Effect of land-use and land-cover change on nutrients in soil in Bashang area,China 被引量:1
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作者 SHENG Xue-bin SUN Jian-zhong LIU Yun-xia 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第4期548-553,共6页
The Bashang area is a water source area and ecological barrier zone for Beijing and Tianjin. The area is located at 200 km from Beijing and Tianjin and is a typical agriculture pasture interlacing zone, in which th... The Bashang area is a water source area and ecological barrier zone for Beijing and Tianjin. The area is located at 200 km from Beijing and Tianjin and is a typical agriculture pasture interlacing zone, in which the eco environment is vulnerable and hence it is sensitive to environmental change. The area is relatively lagged in social and economic development, where the traditional cultivation mode is predominated in agriculture and animal husbandry, but the disturbance by human activity is relatively small. Therefore, in order to reveal the interrelation between eco environmental change in the area and environmental change in Beijing and Tianjin area, it is fairly necessary to study the effect of land use and land cover change on nutrients in soil in this area. According to the actual situation of changed land use for the limited time period, five series of changed land plots were selected and 4 samples were collected from each series for the study. The samples were collected from different soil forming levels at the same site in different time. Analysis of the collected samples indicates that in the process of change of land use and land cover, the nutrients in soil, such as organic matter, total N, total P, total K, and available N, P, K, and B, Mo, Mn, Zn, Cu, and Fe, have regularly changed. When the land had changed from grassland and non irrigated farmland into woodland, and from non irrigated farmland into irrigated field, the nutrients in soil totally increased. But there exists some exception, i.e. quick acting N, P, K, and some microelements have appeared to be inconsistent with the mentioned above regularity in some cases. 展开更多
关键词 Bashang area land use change variation of nutrients
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Diurnal brooding behavior of long-tailed tits (Aegithalos caudatus glaucogularis) 被引量:2
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作者 Jin YU Peng-Cheng WANG +7 位作者 Lei LU Zheng-Wang ZHANG Yong WANG Ji-Liang XU Jian-Qiang LI Bo XI Jia-Gui ZHU Zhi-Yong DU 《Zoological Research》 CAS CSCD 2016年第2期84-89,共6页
Brooding is a major breeding investment of parental birds during the early nestling stage, and has important effects on the development and survival of nestlings. Investigating brooding behavior can help to understand... Brooding is a major breeding investment of parental birds during the early nestling stage, and has important effects on the development and survival of nestlings. Investigating brooding behavior can help to understand avian breeding investment strategies. From January to June in 2013 and 2014, we studied the brooding behaviors of long-tailed tits (Aegithalos caudatus glaucogularis) in Dongzhai National Nature Reserve, Henan Province, China. We analyzed the relationships between parental diurnal brooding duration and nestling age, brood size, temperature, relative breeding season, time of day and nestling frequencies during brooding duration. Results showed that female and male long-tailed tit parents had different breeding investment strategies during the early nestling stage. Female parents bore most of the brooding investment, while male parents performed most of the nestling feedings. In addition, helpers were not found to brood nestlings at the two cooperative breeding nests. Parental brooding duration was significantly associated with the food delivered to nestlings (F=86.10, dr=l, 193.94, P〈0.001), and was longer when the nestlings received more food. We found that parental brooding duration declined significantly as nestlings aged (F=5.99, dr=-1, 50.13, P=0.018). When nestlings were six days old, daytime parental brooding almost ceased, implying that long- tailed tit nestlings might be able to maintain their own body temperature by this age. In addition, brooding duration was affected by both brood size (F=12.74, dr=-1,32.08, P=0.001) and temperature (F=5.83, df=-l, 39.59, P=-0.021), with it being shorter in larger broods and when ambient temperature was higher. 展开更多
关键词 Long-tailed tit Aegithalos caudatusglaucogularis BROODING DAYTIME Early nestling stage
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Jinfengopteryx Compared to Archaeopteryx,with Comments on the Mosaic Evolution of Long-tailed Avialan Birds 被引量:1
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作者 JI Shu'an JI Qiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第3期337-343,共7页
Jinfengopteryx is a newly uncovered Archaeopteryx-like avialan bird outside Germany, which was found from the Jehol Biota of northern Hebei in northeastern China. It shares many characters only with Archaeopteryx by t... Jinfengopteryx is a newly uncovered Archaeopteryx-like avialan bird outside Germany, which was found from the Jehol Biota of northern Hebei in northeastern China. It shares many characters only with Archaeopteryx by the possession of three fenestrae in the antorbital cavity, 23 caudal vertebrae and long tail feathers attached to all the caudal vertebrae. But the former differs from the latter in the relatively short and high preorbital region of skull, more and closely packed teeth, much shorter forelimb compared to hindlimb. Such differences indicate Jinfengopteryx is even slightly more primitive than Archaeopteryx, although both birds can be placed at the root position of the avialan tree based on cladistic analysis. Shenzhouraptor is suggested to be slightly more advanced than Jinfengopteryx + Archaeopteryx, supported by some derived features in teeth, shoulder girdles and forelimbs such as the reduction of tooth number, dorsolaterally directed glenoid facet, very long forelimb and comparatively short manus. Meanwhile, the tail of Shenzhouraptor shows more primitive characters than those of Jinfengopteryx and Archaeopteryx, e.g., the strikingly longer tail composed of more caudal vertebrae and the long tail feathers attached only to distal caudal segments. The mixed primitive and advanced characters reveal the evident mosaic evolution among long-tailed avialan birds. 展开更多
关键词 Jinfengopteryx Archaeopteryx long-tailed avialans mosaic evolution MESOZOIC
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大豆异黄酮对坝上长尾鸡生长性能、免疫功能、睾丸发育及血浆生殖激素的影响 被引量:4
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作者 马利芹 官丽辉 利凯 《饲料研究》 CAS 北大核心 2024年第1期34-39,共6页
试验旨在研究大豆异黄酮对坝上长尾鸡生长性能、免疫功能、睾丸发育及生殖激素的影响。选取750只40周龄坝上长尾鸡,随机分为5组,每组3个重复,每个重复50只鸡。Ⅰ组、Ⅱ组、Ⅲ组、Ⅳ组和Ⅴ组饲粮中分别添加5、10、15、20、25 mg/kg大豆... 试验旨在研究大豆异黄酮对坝上长尾鸡生长性能、免疫功能、睾丸发育及生殖激素的影响。选取750只40周龄坝上长尾鸡,随机分为5组,每组3个重复,每个重复50只鸡。Ⅰ组、Ⅱ组、Ⅲ组、Ⅳ组和Ⅴ组饲粮中分别添加5、10、15、20、25 mg/kg大豆异黄酮。预试期7 d,正式试验期63 d。结果显示,Ⅱ组、Ⅲ组、Ⅳ组和Ⅴ组坝上长尾鸡增重显著高于Ⅰ组(P<0.05)。Ⅲ组坝上长尾鸡的胸腺指数显著高于其他组(P<0.05);Ⅲ组坝上长尾鸡的法氏囊指数分别比Ⅰ组、Ⅱ组和Ⅴ组显著提高16.09%、14.70%和22.67%(P<0.05);Ⅲ组坝上长尾鸡的脾脏指数比Ⅰ组显著提高17.98%(P<0.05)。Ⅲ组坝上长尾鸡的睾丸指数最高,显著高于Ⅰ组(P<0.05),提高了11.74%。Ⅲ组坝上长尾鸡的采精量、精子密度和有效精子数显著高于Ⅰ组(P<0.05),分别提高了9.52%、4.79%和8.97%。Ⅲ组坝上长尾鸡的睾酮(TESTO)含量分别比Ⅰ组、Ⅱ组和Ⅴ组显著提高10.42%、4.72%和6.42%(P<0.05);Ⅲ组坝上长尾鸡的黄体生成素(LH)含量分别比Ⅰ组、Ⅱ组和Ⅴ组显著提高7.63%、5.83%和10.12%(P<0.05)。研究表明,大豆异黄酮能够改善坝上长尾鸡的生长性能、免疫功能、睾丸发育、精液品质及血浆生殖激素的分泌水平,且最适添加量为15 mg/kg。 展开更多
关键词 大豆异黄酮 坝上长尾鸡 免疫功能 睾丸发育 血浆生殖激素
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Environmental change in Bashang Region historical periods
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作者 SHENG Xue-bin SUN Jian-zhong +1 位作者 LIU Yun-xia FENG Jiang-bin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第2期224-227,共4页
The Bashang region is a typical vulnerable eco-environmental zone. Our analysis of paleodunes, paleosol profiles, and lake changes taking place during last ten thousands years indicated that: (1) 10 - 6.9 ka B. P. was... The Bashang region is a typical vulnerable eco-environmental zone. Our analysis of paleodunes, paleosol profiles, and lake changes taking place during last ten thousands years indicated that: (1) 10 - 6.9 ka B. P. was a post-glacial temperature-increasing stage, in which lakes had their high water level; (2) 6.9 - 3.0 ka B. P. was a large warm stage, during which four paleosol layers were developed and climate fluctuation has assumed 4 - 5 small cold-humid and cold-dry alternations. Since 5.4 ka B. P, the lakes tended to gradually shrink; and by 2.1 ka B. P., water level has fallen by 2.7 m; (3) since 3.0 ka B. P. a general trend of the region was to change into a dry, warm-dry and cold-dry environment. 展开更多
关键词 Bashang region environmental change
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Effects of grassland degradation on chestnut soil properties in Bashang Plateau, China
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作者 SHENG Xue bin\+1, LIU Yun\|xia\+1, ZHAO Yu\|ping\+2 (1. Research Center for Eco\|Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China 2. China University of Agriculture, Beijing 100094, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第1期105-109,共5页
The repeated effects of vulnerable habitat and unreasonable human activities on the Bashang Plateau of China led the chestnut soil to degrade. It expresses in reducing soil CEC, decreasing nutrient content, decomposi... The repeated effects of vulnerable habitat and unreasonable human activities on the Bashang Plateau of China led the chestnut soil to degrade. It expresses in reducing soil CEC, decreasing nutrient content, decomposing organic complexes, and reducing humus in loose, steady and tight bond forms, respectively. The percentage of three forms are 21%—34%, 44%—55% and 5%—6.2%, respectively. 展开更多
关键词 Bashang Plateau chestnut soil organic and inorganic complexes humus bond form CLC number: S152.4 Document code: A
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Temporal and Spatial Evolution of Lakes in the Bashang Plateau for Nearly Recent 30 Years
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作者 Xiujuan Li Sugai Gao +2 位作者 Wenli Li Guifu Qiu Zhiyuan Tian 《Journal of Water Resource and Protection》 CAS 2022年第10期698-708,共11页
Lakes are important ecological water sources in the Bashang Plateau. Its expansion or shrinkage directly affects the ecological security of the plateau and its surrounding areas. In this study, Landsat images from 198... Lakes are important ecological water sources in the Bashang Plateau. Its expansion or shrinkage directly affects the ecological security of the plateau and its surrounding areas. In this study, Landsat images from 1984 to 2015 were selected to monitor the area of lakes in the Bashang Plateau and to analyze the spatiotemporal evolution and driving forces of lakes in the Bashang Plateau. The results showed that there were 47 lakes in the Bashang Plateau in 2015, with a total area of 37.63 km2, mainly distributed in the central and western regions of the region. From 1984 to 2015, the lakes in Bashang Plateau showed a shrinking trend. At the same time, there are obvious stage differences in lake changes. During 1984-1996, the number of lakes increased by 99 and the total area increased by 124.43 km2. From 1996 to 2015, the number of lakes decreased by 142, and the total area decreased by 183.96 km2. Before 1996, climate change was the dominant factor. However, the shrinkage of lakes after 1996 is the result of climate change and human activities. Among them, the large-scale planting of water consuming crops such as vegetables is the main human activity mode leading to lake shrinkage. This study will help to understand the expansion and contraction factors of the Bashang Plateau lakes in Hebei province and provide a reference for the future protection and management of the lakes. 展开更多
关键词 Bashang Plateau Lake Area Spatial and Temporal Patterns Evolution Driving Force
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M^(2)LC-Net: A Multi-Modal Multi-Disease Long-Tailed Classification Network for Real Clinical Scenes
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作者 Zhonghong Ou Wenjun Chai +9 位作者 Lifei Wang Ruru Zhang Jiawen He Meina Song Lifei Yuan Shengjuan Zhang Yanhui Wang Huan Li Xin Jia Rujian Huang 《China Communications》 SCIE CSCD 2021年第9期210-220,共11页
Leveraging deep learning-based techniques to classify diseases has attracted extensive research interest in recent years.Nevertheless,most of the current studies only consider single-modal medical images,and the numbe... Leveraging deep learning-based techniques to classify diseases has attracted extensive research interest in recent years.Nevertheless,most of the current studies only consider single-modal medical images,and the number of ophthalmic diseases that can be classified is relatively small.Moreover,imbalanced data distribution of different ophthalmic diseases is not taken into consideration,which limits the application of deep learning techniques in realistic clinical scenes.In this paper,we propose a Multimodal Multi-disease Long-tailed Classification Network(M^(2)LC-Net)in response to the challenges mentioned above.M^(2)LC-Net leverages ResNet18-CBAM to extract features from fundus images and Optical Coherence Tomography(OCT)images,respectively,and conduct feature fusion to classify 11 common ophthalmic diseases.Moreover,Class Activation Mapping(CAM)is employed to visualize each mode to improve interpretability of M^(2)LC-Net.We conduct comprehensive experiments on realistic dataset collected from a Grade III Level A ophthalmology hospital in China,including 34,396 images of 11 disease labels.Experimental results demonstrate effectiveness of our proposed model M^(2)LC-Net.Compared with the stateof-the-art,various performance metrics have been improved significantly.Specifically,Cohen’s kappa coefficient κ has been improved by 3.21%,which is a remarkable improvement. 展开更多
关键词 deep learning multi modal long-tail ophthalmic disease classification
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Semi-supervised Long-tail Endoscopic Image Classification
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作者 Runnan Cao Mengjie Fang +2 位作者 Hailing Li Jie Tian Di Dong 《Chinese Medical Sciences Journal》 CAS CSCD 2022年第3期171-180,I0002,共11页
Objective To explore the semi-supervised learning(SSL) algorithm for long-tail endoscopic image classification with limited annotations.Method We explored semi-supervised long-tail endoscopic image classification in H... Objective To explore the semi-supervised learning(SSL) algorithm for long-tail endoscopic image classification with limited annotations.Method We explored semi-supervised long-tail endoscopic image classification in HyperKvasir,the largest gastrointestinal public dataset with 23 diverse classes.Semi-supervised learning algorithm FixMatch was applied based on consistency regularization and pseudo-labeling.After splitting the training dataset and the test dataset at a ratio of 4:1,we sampled 20%,50%,and 100% labeled training data to test the classification with limited annotations.Results The classification performance was evaluated by micro-average and macro-average evaluation metrics,with the Mathews correlation coefficient(MCC) as the overall evaluation.SSL algorithm improved the classification performance,with MCC increasing from 0.8761 to 0.8850,from 0.8983 to 0.8994,and from 0.9075 to 0.9095 with 20%,50%,and 100% ratio of labeled training data,respectively.With a 20% ratio of labeled training data,SSL improved both the micro-average and macro-average classification performance;while for the ratio of 50% and 100%,SSL improved the micro-average performance but hurt macro-average performance.Through analyzing the confusion matrix and labeling bias in each class,we found that the pseudo-based SSL algorithm exacerbated the classifier’ s preference for the head class,resulting in improved performance in the head class and degenerated performance in the tail class.Conclusion SSL can improve the classification performance for semi-supervised long-tail endoscopic image classification,especially when the labeled data is extremely limited,which may benefit the building of assisted diagnosis systems for low-volume hospitals.However,the pseudo-labeling strategy may amplify the effect of class imbalance,which hurts the classification performance for the tail class. 展开更多
关键词 endoscopic image artificial intelligence semi-supervised learning long-tail distribution image classification
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Study on multiple induced polarization parameters in groundwater exploration in Bashang poverty alleviation area of Heibei Province,China
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作者 LIU Zhi-yuan TAN Ding +3 位作者 CHEN Zhi-bin WEI Yun-fei CHAI Quan CHEN Xiao-hang 《Journal of Groundwater Science and Engineering》 2020年第3期274-280,共7页
The study examines a water exploration and poverty alleviation project in Guyuan county.The study analyzes correlations between aquifers and multiple induced polarization(IP)parameters,including resistivity,polarizabi... The study examines a water exploration and poverty alleviation project in Guyuan county.The study analyzes correlations between aquifers and multiple induced polarization(IP)parameters,including resistivity,polarizability,deviation,half decay time,water-bearing factors,and Kc,a new parameter refined in this study.Based on the study,the well was placed accurately,and its maximum water inflow reached 30 m3/h.Kc value highlights the rate of change at early stages of IP secondary field.Kc value served as a quick indicator in this groundwater prospecting and is validated in practice.Progress has been made in finding new parameters in exploring water with IP method.Thanks to the project,local people have access to water and poverty alleviation has scored some achievements. 展开更多
关键词 Bashang Induced polarization parameters Decay rate Secondary field
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Planting Experiment of Five Quinoa Varieties in Bashang Area of Hebei Province
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作者 Zhimin WEI Meng LIU +4 位作者 Yu ZHAO Chuan LU Jianjun LIU Shunguo LI Wei LV 《Meteorological and Environmental Research》 CAS 2022年第1期84-85,共2页
It is very suitable for planting quinoa in Bashang area of Hebei Province,but the local varieties of quinoa are disordered,which affects the development of quinoa industry.In this experiment,five quinoa varieties were... It is very suitable for planting quinoa in Bashang area of Hebei Province,but the local varieties of quinoa are disordered,which affects the development of quinoa industry.In this experiment,five quinoa varieties were selected and planted in Guyuan County.After two years of experiment,scientific conclusions were drawn on the yield,agronomic characters,economic characters,stress resistance and regional adaptability of these five varieties,and objective evaluation of variety characteristics and production and utilization value was conducted,which can provide scientific basis for variety identification,variety distribution and application of quinoa,and provide feedback information for promoting the development of quinoa industry. 展开更多
关键词 QUINOA Planting test Bashang area
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Effects of Different Modes of Returning Farmland to Forest on Physicochemical Properties of Soil in Bashang Area of Northern Hebei Province
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作者 Yue YANG Yitian YANG +2 位作者 Zhiyong WU Caiwu WU Yongjiao HAN 《Meteorological and Environmental Research》 CAS 2020年第4期98-102,共5页
[Objective]The research aimed to understand the change rules of physicochemical properties of soil in the different modes of returning farmland to forest.[Method]The physicochemical properties of soil in three differe... [Objective]The research aimed to understand the change rules of physicochemical properties of soil in the different modes of returning farmland to forest.[Method]The physicochemical properties of soil in three different types of returning farmland to forest(Hippophae rhamnoides Linn.forest,Caragana korshinskii forest and Ulmus pumila L.forest)were analyzed by taking the enclosed grassland as comparison in Bashang area of northern Hebei Province.[Result]The results showed that there were significant differences among different types.Order of the bulk density of soil:H.rhamnoides Linn.forest(1.17 g/cm^3)<U.pumila L.forest(1.24 g/cm^3)<C.korshinskii forest(1.26 g/cm^3)<enclosed grassland(1.61 g/cm^3);order of the total porosity of soil:H.rhamnoides Linn.forest(55.29%)>U.pumila L.forest(52.55%)>C.korshinskii forest(51.93%)<enclosed grassland(38.85%);order of the organic matter content of soil:H.rhamnoides Linn.forest(3.191%)>C.korshinskii forest(3.128%)>U.pumila L.forest(2.804%)>enclosed grassland(2.536%).[Conclusion]After returning farmland to forest,vegetation played a positive role in physicochemical properties of soil.There were significant differences in physicochemical properties of soil among different modes of returning farmland to forest,and the improvement effect of H.rhamnoides Linn.forest on physicochemical properties of soil was the best. 展开更多
关键词 Returning farmland to forest Physicochemical properties of soil Bashang area of northern Hebei Province
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Dual Channel with Involution for Long-Tailed Visual Recognition
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作者 Mengxue Li 《Open Journal of Applied Sciences》 2022年第4期421-433,共13页
With the rapid increase of large-scale problems, the distribution of real-world datasets tends to be long-tailed. Existing solutions typically involve re-balancing strategies (i.e., re-sampling and re-weighting). Alth... With the rapid increase of large-scale problems, the distribution of real-world datasets tends to be long-tailed. Existing solutions typically involve re-balancing strategies (i.e., re-sampling and re-weighting). Although they can significantly promote the classifier learning of deep networks, they will unexpectedly impair the representative ability of the learned deep features to a certain extent. Therefore, this paper proposes a dual-channel learning algorithm with involution neural networks (DC-Invo) to take care of representation learning and classifier learning concurrently. In this work, the most important thing is to combine ResNet and involution to obtain higher classification accuracy because of involution’s wider coverage in the spatial dimension. The paper conducted extensive experiments on several benchmark vision tasks including Cifar-LT, Imagenet-LT, and Places-LT, showing that DC-Invo is able to achieve significant performance gained on long-tailed datasets. 展开更多
关键词 Long-Tailed Recognition Deep Neural Network Dual-Channel Structure INVOLUTION
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坝上地区莜麦秸秆热解特性研究
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作者 刘联胜 梁小虎 +2 位作者 王冬计 张晓宇 黄亚龙 《可再生能源》 CAS CSCD 北大核心 2024年第3期293-299,共7页
为实现高寒坝上地区农作物秸秆高效清洁燃烧,文章选取典型莜麦秸秆作为研究对象,通过混合气体模拟烟气燃烧过程中的热解气氛环境,采用热重分析仪研究空气和N_(2),CO_(2),O_(2)不同比例组成的混合气体氛围下热失重特性以及升温速率对其影... 为实现高寒坝上地区农作物秸秆高效清洁燃烧,文章选取典型莜麦秸秆作为研究对象,通过混合气体模拟烟气燃烧过程中的热解气氛环境,采用热重分析仪研究空气和N_(2),CO_(2),O_(2)不同比例组成的混合气体氛围下热失重特性以及升温速率对其影响,采用AKTS软件进行动力学分析。结果表明:莜麦秸秆热解过程可分为干燥(30~140℃)、挥发(140~370℃)、炭化(370~900℃)3个阶段;气体氛围主要影响热解的炭化阶段,对干燥和挥发阶段影响较小;升温速率影响挥发和炭化阶段,升温速率越快,反应速率越大;当热解气氛为15%O_(2)-5%CO_(2)-80%N_(2)混合气体(气体2)时,热解过程所需活化能最少,平均活化能为139.86 kJ/mol。研究结果可为高寒坝上地区生物质秸秆能源化利用提供一定理论依据。 展开更多
关键词 坝上地区 莜麦秸秆 热解特性 活化能
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中草药对产蛋后期坝上长尾鸡产蛋性能、蛋品质、血清抗氧化性、激素水平和免疫因子的影响 被引量:4
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作者 于禧凝 李琴 +5 位作者 张馨 闫婧较 赵志强 林向前 李杰峰 范春艳 《饲料研究》 CAS 北大核心 2024年第5期38-42,共5页
试验旨在研究中草药对产蛋后期坝上长尾鸡产蛋性能、蛋品质和血清指标的影响。试验选取240羽470日龄的坝上长尾鸡,随机分为4组,每组6个重复,每个重复10羽鸡。对照组饲喂基础饲粮,试验组分别在基础饲粮中添加1.0%、1.5%和2.0%的中草药添... 试验旨在研究中草药对产蛋后期坝上长尾鸡产蛋性能、蛋品质和血清指标的影响。试验选取240羽470日龄的坝上长尾鸡,随机分为4组,每组6个重复,每个重复10羽鸡。对照组饲喂基础饲粮,试验组分别在基础饲粮中添加1.0%、1.5%和2.0%的中草药添加剂。预试期7 d,正式试验期56 d。结果显示,与对照组相比,1.5%剂量组产蛋率显著升高(P<0.05),1.0%、2.0%剂量组鸡蛋的平均蛋重显著升高(P<0.05);1.0%、1.5%剂量组鸡蛋的哈夫单位有升高趋势(P>0.05),1.5%剂量组鸡蛋的蛋壳厚度显著升高(P<0.05);1.5%剂量组血清中谷胱甘肽过氧化物歧化酶(GSH-Px)活性显著升高(P<0.05);试验各组血清中促黄体激素(LH)、雌二醇(E2)和孕酮(Prog)水平极显著升高(P<0.01),1.5%、2.0%剂量组血清中促卵泡激素(FSH)水平极显著升高(P<0.01);1.5%、2.0%剂量组血清中γ干扰素(IFN-γ)水平极显著升高(P<0.01),2.0%剂量组血清中白细胞介素-2 (IL-2)水平极显著升高(P<0.01)。研究表明,饲粮中添加中草药添加剂可提高产蛋后期坝上长尾鸡的产蛋率,改善蛋品质,增强机体抗氧化能力,促进生殖激素的分泌,提高了免疫功能,中草药适宜添加量为1.5%。 展开更多
关键词 中草药添加剂 坝上长尾鸡 产蛋性能 蛋品质 抗氧化能力 生殖激素 免疫因子
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不同能量、粗蛋白水平对坝上长尾鸡产蛋性能、蛋品质及血清生化指标的影响
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作者 李文菊 和雁南 +4 位作者 章飞 樊萌 兰寅峰 刘海斌 张立永 《黑龙江畜牧兽医》 CAS 北大核心 2024年第22期63-67,共5页
为了研究不同能量、粗蛋白水平对坝上长尾鸡产蛋性能、蛋品质及血清生化指标的影响,试验将145日龄、体重相近、健康的雌性坝上长尾鸡300只分为6组,分别饲喂不同能量和蛋白水平的日粮[试验Ⅰ组代谢能(ME)11.00 MJ/kg、粗蛋白(CP)15.00%,... 为了研究不同能量、粗蛋白水平对坝上长尾鸡产蛋性能、蛋品质及血清生化指标的影响,试验将145日龄、体重相近、健康的雌性坝上长尾鸡300只分为6组,分别饲喂不同能量和蛋白水平的日粮[试验Ⅰ组代谢能(ME)11.00 MJ/kg、粗蛋白(CP)15.00%,试验Ⅱ组ME 11.00 MJ/kg、CP 16.00%,试验Ⅲ组ME 11.00 MJ/kg、CP 17.00%,试验Ⅳ组ME 11.57 MJ/kg、CP 15.00%,试验Ⅴ组ME 11.57 MJ/kg、CP 16.00%,试验Ⅵ组ME 11.57 MJ/kg、CP 17.00%],预试期7 d,正试期35 d,测定产蛋率、平均蛋重、料蛋比、平均日采食量及开产体重,蛋形指数、蛋壳强度、蛋壳厚度、蛋白高度、哈氏单位、蛋黄颜色,以及血清血糖、三酰甘油、总胆固醇、总蛋白、白蛋白、尿素氮、生长激素含量和天冬氨酸转氨酶、丙氨酸转氨酶活性。结果表明:试验Ⅲ组、Ⅴ组和Ⅵ组产蛋率显著高于试验Ⅰ组(P<0.05);试验Ⅰ组料蛋比极显著高于试验Ⅴ组(P<0.01),显著高于试验Ⅲ、Ⅵ组(P<0.05),试验Ⅲ组、Ⅴ组和Ⅵ组平均蛋重显著高于试验Ⅰ组、Ⅱ组和Ⅳ组(P<0.05);蛋形指数、蛋壳强度、哈氏单位各组均差异不显著(P>0.05);试验Ⅴ组蛋黄颜色、蛋白高度显著高于Ⅰ组(P<0.05),其余各组差异不显著(P>0.05);试验Ⅵ组血清总胆固醇含量显著高于Ⅰ组(P<0.05),其余各组间差异不显著(P>0.05);试验Ⅵ组血清总蛋白含量最高,试验Ⅰ组最低,但各组差异不显著(P>0.05);试验Ⅴ组血清尿素氮含量显著高于试验Ⅰ组、Ⅱ组和Ⅳ组(P<0.05);各组血清天冬氨酸转氨酶、丙氨酸转氨酶活性均差异不显著(P>0.05);试验Ⅲ组、Ⅴ组和Ⅵ组血清生长激素含量显著高于试验Ⅰ组(P<0.05),其余各组间差异不显著(P>0.05)。说明坝上长尾鸡母鸡适宜的日粮能量水平为11.57 MJ/kg、粗蛋白水平为16.00%。 展开更多
关键词 坝上长尾鸡 能量水平 蛋白水平 产蛋性能 蛋品质 血清生化指标
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