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Comparison of Low Stress Mechanical Properties of Light Weight Wool and Wool Blend Fabrics using the KES-F and FAST Instruments 被引量:1
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作者 王革辉 张渭源 +1 位作者 Postle Ron Phillips David 《Journal of China Textile University(English Edition)》 EI CAS 2000年第4期99-102,共4页
This study compares the test results of the FAST (Fabric Assurance by Simple Testing) with those of the KES - F (Kawabata Evaluation Systems for Fabrics) for a range of nineteen light weight wool and wool blend fabric... This study compares the test results of the FAST (Fabric Assurance by Simple Testing) with those of the KES - F (Kawabata Evaluation Systems for Fabrics) for a range of nineteen light weight wool and wool blend fabrics in terms of the low - stress mechanical properties of bending, shear, and tensile deformation. It is found that there are very significant correlations between the corresponding parameters for extensibility and shear rigidity obtained from the test results of the two systems. The correlation between the values of bending rigidity obtained from the two systems is only moderate. Furthermore, for the fabrics tested in this study, the values of bending rigidity, shear rigidity, and extensibility measured using the KES - F instruments are higher than those of the corresponding parameters measured using the FAST instruments. The linear regression equation is given for each pair of corresponding parameter. 展开更多
关键词 low stress MECHANICAL properties the KES - F SYSTEM the FAST SYSTEM light weight WOOL FABRICS
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Preparation of Light-weight Spinel Refractories by Foaming-gel Process 被引量:2
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作者 FENG Zhiyuan SHI Gan +1 位作者 ZHANG Wei KUANG Yunhui 《China's Refractories》 CAS 2013年第4期28-32,共5页
Light-weight magnesium -aluminate spinel materi- als were prepared by foaming-gel process with polyalumi- nium chloride (PAC) as gel. Effect of solid loading in initial slurry on microstructure, porosity, pore size ... Light-weight magnesium -aluminate spinel materi- als were prepared by foaming-gel process with polyalumi- nium chloride (PAC) as gel. Effect of solid loading in initial slurry on microstructure, porosity, pore size distri- bution, thermal conductivity and mechanical properties was investigated. The results show that the bulk density of the light-weight magnesium -aluminate spinel mate- rials is in the range of O. 7 1.2 g cm-3 ; pore size distribution curves show single-peak characteristics and the mean pore size is in the range of 30. 83 - 61.37 μm ; with the increase of solid loading, the linear shrinkage of the green body during firing and the permanent change in dimensions on heating at l 600 ℃ for 3 h de- crease, but the bulk density increases, the mechanical properties increase obviously; the maximum compressive strength and bending strength reach 35. 25 MPa and 9. 92 MPa, respectively, while the bulk density is 1. 16 g · cm ; and the thermal conductivity at 1 000 ℃ tea- ches 0. 371 W · m-1 . K-1 while the bulk density is O. 7 -3 g · cm 展开更多
关键词 magnesium - aluminate spinel light-weight materials foaming-gel pore size distribution thermal conductivity
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Light-Weight Design Method for Force-Performance-Structure of Complex Structural Part Based Co-operative Optimization 被引量:3
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作者 Ya-Li Ma Jian-Rong Tan +1 位作者 De-Lun Wang Zi-Zhe Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第2期115-123,共9页
A light?weight design method of integrated structural topology and size co?optimization for the force?performance?structure of complex structural parts is presented in this paper. Firstly, the supporting function of a... A light?weight design method of integrated structural topology and size co?optimization for the force?performance?structure of complex structural parts is presented in this paper. Firstly, the supporting function of a complex structural part is built to map the force transmission, where the force exerted areas and constraints are considered as connecting structure and the structural configuration, to determine the part performance as well as the force routines. Then the connecting structure design model, aiming to optimize the static and dynamic performances on connection configuration, is developed, and the optimum design of the characteristic parameters is carried out by means of the collaborative optimization method, namely, the integrated structural topology optimization and size optimization. In this design model, the objective is to maximize the connecting stiffness. Based on the relationship between the force and the structural configuration of a part, the optimal force transmission routine that can meet the performance requirements is obtained using the structural topology optimization technology. Accordingly, the light?weight design of conceptual configuration for complex parts under multi?objective and multi?condition can be realized. Finally, based on the proposed collaborative optimization design method, the optimal performance and optimal structure of the complex parts with light weight are realized, and the reasonable structural unit configuration and size charac?teristic parameters are obtained. A bed structure of gantry?type machining center is designed by using the proposed light?weight structure design method in this paper, as an illustrative example. The bed after the design optimization is lighter 8% than original one, and the rail deformation is reduced by 5%. Moreover, the lightweight design of the bed is achieved with enhanced performance to show the effectiveness of the proposed method. 展开更多
关键词 light?weight design Part structure Topology optimization Size optimization FORCE PERFORMANCE
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Long-Term Continuous Light Exposure Affects Body Weight and Blood Glucose Associated with Inflammation in Female Rats 被引量:1
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作者 Xuezhi Kang Lina Jia +4 位作者 Xu Zhang Yaming Li Yi Chen Xueyong Shen Yaochi Wu 《Journal of Biosciences and Medicines》 2016年第9期11-24,共14页
Studies have indicated that night lights interfere with the circadian rhythm in the human body and threaten human health. Our previous studies indicated that continuous light exposure severely damages the reproductive... Studies have indicated that night lights interfere with the circadian rhythm in the human body and threaten human health. Our previous studies indicated that continuous light exposure severely damages the reproductive endocrine system of female rats resembles polycystic ovary syndrome in women. In this study, we used the continuous measurement method to observe changes in the basal physiological indicators of female rats in an abnormal light exposure environment. Our study results indicated that in female rats: 1) the body temperature first continuously and gradually increased followed by a gradually decrease;2) the increase in body weight slowed down at the late stage of the experimental process;3) the random blood glucose level increased, and the fasting serum insulin level decreased;and 4) the serum C-reactive protein level increased. Our study investigated for the first time the correlation between the duration of continuous light exposure in female rats and the continuously measured basal physiological indicators and preliminarily discussed the effect of continuous light exposure on female basal metabolism and the possible inflammation mechanism. We propose that long-term continuous exposure to night lights in females severely damages their immune and metabolic systems. 展开更多
关键词 Continuous light Exposure Body weight Blood Glucose INFLAMMATION Comparative Study
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Light weight analysis of a skeleton vehicle frame using BS960 super-high-strength steel 被引量:1
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作者 HAO Xin WANG Yong CAI Zheng 《Baosteel Technical Research》 CAS 2016年第2期40-44,共5页
Static strength finite element analysis was conducted to decrease the weight of a skeleton vehicle's frame. Results indicated that the maximum stress occurs on the front beam 's variable section area. Dynamic sensit... Static strength finite element analysis was conducted to decrease the weight of a skeleton vehicle's frame. Results indicated that the maximum stress occurs on the front beam 's variable section area. Dynamic sensitivity analysis elucidated the relationship between the maximum stress and the thickness of a particular beam,e. g.,top,middle,and bottom beam. Displacement was analyzed by the key part that influenced the maximum stress. Finally,the new plan using BS960 super-high-strength beam steel and the preferred beam thickness was compared with the original plan. New combinations of beam thickness were introduced on the basis of different purposes; the maximum responding light w eight ratio was 21%. 展开更多
关键词 skeleton vehicle frame finite element analysis dynamic sensitivity analysis BS960 super-high-strength beam steel light weight
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Ultra-thin and light-weight spoof surface plasmon polariton coupler achieved by broadside coupled split ring resonators
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作者 Ya Fan Jia-Fu Wang +3 位作者 Hua Ma Yong-Feng Li Ming-De Feng Shao-Bo Qu 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第10期175-180,共6页
Low profile and light weight are very important for practical applications of a spoof surface plasmon polariton(SSPP)coupler, especially at low frequencies. In this paper, we propose and design an ultra-thin, light-... Low profile and light weight are very important for practical applications of a spoof surface plasmon polariton(SSPP)coupler, especially at low frequencies. In this paper, we propose and design an ultra-thin, light-weight SSPP coupler based on broadside coupled split ring resonators(BC-SRRs). The size of BC-SRR can be far less than λ/100 and can extremely well control the reflective phases within a subwavelength thickness. Due to the broadside capacitive coupling, the electrical size of BC-SRR is dramatically reduced to guarantee the ultra-thin thickness of the SSPP coupler. The weight of the SSPP coupler is reduced by a low occupation ratio of BC-SRR in the unit cell volume. As an example, a C-band SSPP coupler composed of phase gradient BC-SRRs is designed, fabricated, and measured. Due to the ultra-small size and low occupation ratio of BC-SRRs, the thickness of the coupler is λ/12 and the surface density is only 0.98 kg/m^2. Both simulation and experiment results verify that the coupler can achieve high-efficiency SPP coupling at 5.27 GHz under normal incidence. 展开更多
关键词 ULTRA-THIN light-weight poof surface plasmon polariton broadside coupling
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Principles and Chief Technologies in Developing Light-weighted Worsted Fabrics
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作者 Zhou Qicheng(周启澄) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第3期120-122,共3页
More and more light-weighted fabrics are being required by the market, especially for the worsted manufacture.In the past, such fabrics are produced mainly through changing the structure of woven goods or by using fin... More and more light-weighted fabrics are being required by the market, especially for the worsted manufacture.In the past, such fabrics are produced mainly through changing the structure of woven goods or by using finer yarns. But these possibilities are very limited. In this paper, new devices are discussed: (1) on the yarn level- to use single yarns instead of conventional doubled ones, to decrease number of fibers in yarn cross sections beth during spinning and after finishing; (2) on the fiber level - to use finer fibers in blends with wool and modification of the wool fibers; (3) on the macromolecule level - to stretch the macromolecules in alpha keratin, to get super fine wool fibers. 展开更多
关键词 worsted fabric light-weighted develop.
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Effect of Commercial Synthappret BAP Treatment on the Tailorability of Light-Weight Worsted Wool Fabrics
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作者 王革辉 张渭源 +3 位作者 Postle R. Phillips D. 《Journal of Donghua University(English Edition)》 EI CAS 2001年第2期101-104,共4页
By means of measurement with the FAST instruments, the effect of commercial Synthappret BAP treatment on the tailorability of light-weight wool worsted fabrics has been investigated. It was found that the commercial S... By means of measurement with the FAST instruments, the effect of commercial Synthappret BAP treatment on the tailorability of light-weight wool worsted fabrics has been investigated. It was found that the commercial Synthappret BAP treatment unproved the tailorability of the light-weight wool fabrics mainly by increasing the bending stiffness of the light-weight wool fabrics. 展开更多
关键词 light-weight wool fabric tailonibility commercial Synthappret BAP treatment FORMABILITY
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Effects of Spherical Light-weight Aggregates Additions on Workability and Mechanical Properties of Al_2O_3-SiO_2 System Castables
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作者 YU Renhong LIU Pengcheng +1 位作者 DONG Gaofeng DONG Hongqin 《China's Refractories》 CAS 2017年第4期1-6,共6页
In order to clarify the effect of spherical light-weight aggregates addition on properties of A12 07 - Si02 system castables, adopting ATO mullite traditional light-weight aggregates and ATO mullite spherical light-we... In order to clarify the effect of spherical light-weight aggregates addition on properties of A12 07 - Si02 system castables, adopting ATO mullite traditional light-weight aggregates and ATO mullite spherical light-weight aggre- gates, bauxite homogenization powder, microsilica , cal- cium aluminate cement as main raw materials, light- weight Al2 03 - SiO2 system castables were prepared by replacing conventional light-weight aggregate with spherical light-weight aggregates. The effects of spheri- cal light-weight aggregates addition on workability, me- chanical properties of castables after heated at different temperatures were researched; the microstructure of the aggregates was analyzed by SEM. The result shows that the introduction of spherical light-weight aggregates can significantly improve the flowability and reduce the water addition of the castables. Water demand of the castable is reduced from 18% with the conventional light-weight aggregates to 14% with spherical light-weight aggre- gates. In addition, light-weight castables prepared by spherical aggregates can keep the same workability with- in a wider range of water addition. Therefore, spherical aggregates are user-friendly. The introduction of spheri- cal light-weight aggregates is favorable to packing densi- ty and mechanical properties of castables, such as cold crushing strength, cold modulus of rupture, hot modulus of rupture at 1 200℃. 展开更多
关键词 spherical light-weight aggregates ability mechanical properties alumina - silica castables work- system
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A Study of Thermal Response and Flow Field Coupling Simulation around Hayabusa Capsule Loaded with Light-Weight Ablator
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作者 Hisashi Kihara Naoya Hirata Ken-ichi Abe 《Open Journal of Fluid Dynamics》 2013年第2期100-107,共8页
The numerical simulation of flow field around Hayabusa capsule loaded with light-weight ablator thermal response coupled with pyrolysis gas flow inside the ablator was carried out. In addition, the radiation from high... The numerical simulation of flow field around Hayabusa capsule loaded with light-weight ablator thermal response coupled with pyrolysis gas flow inside the ablator was carried out. In addition, the radiation from high temperature gas around the capsule was coupled with flow field. Hayabusa capsule reentered the atmosphere about 12 km/sec in velocity and Mach number about 30. During such an atmospheric entry, space vehicle is exposed to very savior aerodynamic heating due to convection and radiation. In this study, Hayabusa capsule was treated as a typical model of the atmospheric entry spacecraft. The light-weight ablator had porous structure, and permeability was an important parameter to analyze flow inside ablator. In this study, permeability was a variable parameter dependent on density of ablator. It is found that the effect of permeability of light-weight ablator was important with this analysis. 展开更多
关键词 light-weight Ablator COUPLING CALCULATION PYROLYSIS Gas Flow Hayabusa CAPSULE
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Neuro-fuzzy systems in determining light weight concrete strength
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作者 Seyed Vahid RAZAVI TOSEE Mehdi NIKOO 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第10期2906-2914,共9页
The adaptive neuro-fuzzy inference systems(ANFIS)are widely used in the concrete technology.In this research,the compressive strength of light weight concrete was determined.To this end,the scoria percentage and curin... The adaptive neuro-fuzzy inference systems(ANFIS)are widely used in the concrete technology.In this research,the compressive strength of light weight concrete was determined.To this end,the scoria percentage and curing day variables were used as the input parameters,and compressive strength and tensile strength were used as the output parameters.In addition,100 patterns were used,70%of which were used for training and 30%were used for testing.To assess the precision of the neuro-fuzzy system,it was compared using two linear regression models.The comparisons were carried out in the training and testing phases.Research results revealed that the neuro-fuzzy systems model offers more potential,flexibility,and precision than the statistical models. 展开更多
关键词 neuro-fuzzy systems compressive strength light weight concrete linear regression model
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Development of Light Weight Structures to Provide Blast-Resistant Designs
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作者 CRAWFORD John E 《Transactions of Tianjin University》 EI CAS 2006年第B09期16-21,共6页
In the past, blast-resistant designs for structures were often constructed with massive type structural systems, which relied more on brute strength than on finesse to achieve the required blast resistance. However, s... In the past, blast-resistant designs for structures were often constructed with massive type structural systems, which relied more on brute strength than on finesse to achieve the required blast resistance. However, structures composed of COLD-FORMED steel components, such as sheet metal and metal studs, have shown great promise in providing blast resistance with the added benefits of low cost and ease of construction. Some examples of using such structures to provide containment for package handling facilities (PHF) are described in the paper for situations where blast containment is needed, such as a potential package bomb being discovered during the package vetting process. Results from tests and analytic data are used to illustrate aspects of design peculiar to such types of applications. Designs for specific capacities of PHF are described. 展开更多
关键词 blast containment package handling facility hardened design light weight structures COLD-FORMED steel structures
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基于改进YOLOv7-tiny的高空作业人员安防装备检测算法 被引量:1
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作者 文家燕 周志文 +1 位作者 辛华健 谢广明 《现代电子技术》 北大核心 2024年第13期164-171,共8页
针对现有高空作业人员安防装备检测算法参数量较大且检测目标相对单一,难以适应复杂的高空作业场景等问题,提出一种基于改进YOLOv7-tiny的高空作业人员安防装备检测算法。首先,将主干网络重新设计为更轻量的YOLOv7-FasterNet,并调整空... 针对现有高空作业人员安防装备检测算法参数量较大且检测目标相对单一,难以适应复杂的高空作业场景等问题,提出一种基于改进YOLOv7-tiny的高空作业人员安防装备检测算法。首先,将主干网络重新设计为更轻量的YOLOv7-FasterNet,并调整空间金字塔池化结构,实现模型参数量的压缩;其次,在ELAN-L模块中扩展梯度传输路径的分支,解决了模型压缩造成的通道信息缺失问题,提升了特征信息的提取能力;最后,将网络中下采样部分替换为Involution模块,降低参数冗余,增强网络对全局的捕获能力。实验结果表明,改进的YOLOv7-tiny算法能够更好地适应复杂高空作业场景,在开源数据集上具备良好的性能。该算法的平均检测精度达到94.7%,较原模型提升1.5%,参数量较原模型下降11.6%,实验结果验证了算法改进措施的有效性。 展开更多
关键词 目标检测 安防装备 高空作业 YOLOv7-tiny 轻量化 INVOLUTION
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基于Multi-Light模型的奶牛个体识别研究 被引量:2
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作者 付丽丽 李士军 +2 位作者 孔朔琳 宫鹤 李思函 《黑龙江畜牧兽医》 CAS 北大核心 2023年第3期41-45,51,132,133,共8页
为了解决大规模智能化奶牛养殖场对奶牛个体识别存在模型大、识别速度慢的问题,试验构建了一种用于识别奶牛个体的多尺度轻量化卷积神经网络(Multi-Light)模型,将拍摄的奶牛图像经过标注后利用DeepLab V3模型从复杂背景中分割出单头奶... 为了解决大规模智能化奶牛养殖场对奶牛个体识别存在模型大、识别速度慢的问题,试验构建了一种用于识别奶牛个体的多尺度轻量化卷积神经网络(Multi-Light)模型,将拍摄的奶牛图像经过标注后利用DeepLab V3模型从复杂背景中分割出单头奶牛图像;在Multi-Light模型中引入空洞卷积,保证该模型参数量不变的同时增强提取图像全局信息的能力;加入多尺度卷积模块增强该模型对不同尺度特征点的检测能力,在该模型中使用短路连接以保证特征不丢失,提升模型的识别精度;此外,利用通道注意力机制提高了该模型识别精度,同时使该模型具有更多的非线性;最后将分割得到的奶牛图像数据集输入Multi-Light模型进行训练。结果表明:Multi-Light模型对奶牛个体识别的精度达98.51%,高于其他经典模型对奶牛个体的识别率;与轻量级模型对比,Multi-Light模型的大小为5.86 MB,在具备高识别精度的前提下参数量较少。说明试验所搭建的Multi-Light模型克服了传统方法中需要对特征进行人为提取、提取特征方法不够鲁棒、识别模型参数量大及识别速度慢的缺点,为奶牛个体轻量化识别提供了参考。 展开更多
关键词 空洞卷积 多尺度 轻量化 奶牛识别 跳跃连接
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基于ID-YOLO的数字仪表检测方法
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作者 翟永杰 徐蔚 +3 位作者 韩宇辰 杨珂 赵宽 白云山 《科学技术与工程》 北大核心 2024年第16期6775-6782,共8页
当前针对数字式仪表检测算法在边缘设备具有实时性差、泛化性差的问题,对此提出一种采用ID-YOLO(instrument detection-you only look once)模型的变电站数字仪表检测识别方法。所提算法以YOLOv5模型为基础,首先设计轻量骨干网络(light ... 当前针对数字式仪表检测算法在边缘设备具有实时性差、泛化性差的问题,对此提出一种采用ID-YOLO(instrument detection-you only look once)模型的变电站数字仪表检测识别方法。所提算法以YOLOv5模型为基础,首先设计轻量骨干网络(light weight-YOLO, LW-YOLO)提取图像特征,降低网络参数,提高检测实时性;然后设计了一种双级路由注意力模块(bi-level routing attention moudle, BRAM),提高网络对小数点的检测精度以及网络的鲁棒性和泛化性;最后,引入损失函数α-IoU,通过设定不同的可调节参数α数值得到更准确的真实框与预测框的交并比计算,可以提高模型的检测精度。结果表明:相比于其他基于深度学习的数字仪表检测识别方法,所提方法在不同显示方式的数字仪表识别任务上具有更好的准确性和泛化性,而且可以在检测准确率领先的情况下,将模型在边缘设备上的检测速度从6.87帧/s提升至8.77帧/s,其实时性和检测精度均能够满足实际变电站智能数据采集、检测识别的工程需要。 展开更多
关键词 数字仪表 YOLO(you only look once) 边缘设备 目标检测 轻量化
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1990-2020年长三角地区生境质量与夜间灯光的空间关系
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作者 彭建 吕俭 杨灿灿 《环境科学与技术》 CAS CSCD 北大核心 2024年第1期155-165,共11页
基于1990-2020年长三角地区的土地利用数据和夜间灯光数据,运用InVEST生境质量评估模型、双变量空间自相关、相关系数对生境质量与夜间灯光的时空关系进行研究,并应用地理加权回归和归纳法分析两者的响应规律,结果表明:(1)浙江省总体上... 基于1990-2020年长三角地区的土地利用数据和夜间灯光数据,运用InVEST生境质量评估模型、双变量空间自相关、相关系数对生境质量与夜间灯光的时空关系进行研究,并应用地理加权回归和归纳法分析两者的响应规律,结果表明:(1)浙江省总体上生境最优且城镇发展最快,安徽省在城镇快速发展的同时生境相对下降最少,生境质量和夜间灯光空间分布格局呈现出与区位、地形等因素的空间耦合性。(2)长三角地区生境质量与夜间灯光指数随着时间的发展空间上的依赖性越来越强,聚类模式主要为高-低、低-高及低-低3种。高-低聚类区域主要分布在浙江省和安徽省的南部、西部的山地丘陵,研究期内呈现缩小的趋势;低-高聚类区域在长三角东部平原区呈集聚分布、北部平原丘陵区呈零散分布,呈现扩张趋势。(3)不同年份各省份生境质量与夜间灯光指数呈显著负相关,且经济越发达的省份,生境质量与夜间灯光指数的负相关关系越强;生境质量与夜间灯光指数呈高度负相关的区县主要分布在长江下游沿岸和浙江省东部,相关性不显著的区县主要分布在安徽省、江苏省的北部,变化类型以负相关关系持续增强型占比最高。(4)生境质量与夜间灯光指数的相关关系随着城市发展呈U型变化,即随着城市发展,生境质量与夜间灯光指数的负相关关系先增强后下降。研究结果可为长三角城市可持续发展、生境调控提供前期基础。 展开更多
关键词 生境质量 夜间灯光影像 空间关系 演变规律 地理加权回归 长三角地区
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基于YOLOv8改进的密集行人检测算法:MER-YOLO 被引量:1
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作者 王泽宇 徐慧英 +3 位作者 朱信忠 李琛 刘子洋 王子奕 《计算机工程与科学》 CSCD 北大核心 2024年第6期1050-1062,共13页
在大型人员密集的场所中,人群异常聚集情况时有发生,对自动驾驶和大型公共场所人流量监控系统等应用场景中涉及到的密集行人检测技术带来了一定挑战,新一代的密集行人检测技术要求精确度更高、计算开销更小、检测速度更快以及部署更加... 在大型人员密集的场所中,人群异常聚集情况时有发生,对自动驾驶和大型公共场所人流量监控系统等应用场景中涉及到的密集行人检测技术带来了一定挑战,新一代的密集行人检测技术要求精确度更高、计算开销更小、检测速度更快以及部署更加方便等。针对上述需求,提出了一种基于YOLOv8改进的轻量级密集行人检测算法MER-YOLO,首先采用MobileViT作为主干网络,提升模型在总体上对行人聚集区域的特征提取能力;引入EMA注意力机制模块,对全局信息进行编码,通过维度交互来进一步聚合像素级特征,并结合160×160尺度的检测头加强小目标检测能力;使用排斥损失(Repulsion Loss)作为边界框损失函数,减少了人群密集情况下小目标行人的漏检误检的情况。实验结果表明,相较于YOLOv8n,MER-YOLO行人检测算法在Crowd Human数据集上mAP@0.5提升了4.5%,在WiderPerson数据集上mAP@0.5提升了2.1%,同时只有3.1×10^(6)的参数量和9.8 GFLOPs,满足低算力兼顾高精度的部署需求。 展开更多
关键词 目标检测 行人检测 轻量化 注意力机制
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Influence of expanded polystyrene size on deformation characteristics of light weight soil 被引量:14
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作者 侯天顺 《Journal of Central South University》 SCIE EI CAS 2012年第11期3320-3328,共9页
Deformation characteristics of light weight soil with different EPS (expanded polystyrene) sizes were investigated by consolidation tests.The results show that the confined stress-strain relation curve is in S shape,w... Deformation characteristics of light weight soil with different EPS (expanded polystyrene) sizes were investigated by consolidation tests.The results show that the confined stress-strain relation curve is in S shape,which has a good homologous relation with e-p curve and e-lgp curve,and three types of curves reflect obvious structural characteristics of light weight soil.When cement mixed ratio and EPS volume ratio are the same for different specimens,structural strength decreases with the increase of EPS size,but compressibility indexes basically keep unchanged within the structural strength.The settlement of light weight soil can be divided into instantaneous settlement and primary consolidation settlement.It has no obvious rheology property,and 90% of total consolidation deformation can be finished in 1 min.Settlement-time relation of light weight soil can be predicted by the hyperbolic model.S-lgt curve of light weight soil is not in anti-S shape.It is proved that there is no secondary consolidation section,so consolidation coefficient cannot be obtained by time logarithm method.Structural strength and unit price decrease with the increase of EPS size,but the reducing rate of the structural strength is lower than that of the unit price,so the cost of mixed soil can be reduced by increasing the EPS size.The EPS beads with 3-5 mm in diameter are suggested to be used in the construction process,and the prescription of mixed soil can be optimized. 展开更多
关键词 light weight soil expanded polystyrene (EPS) size effect one-dimensional consolidation theory compressibility index structural strength consolidation test
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LIGHT、IFN-γ基因转染人肝癌HepG2细胞凋亡及其Caspase-3和survivin表达
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作者 毕崇尧 吴力群 +3 位作者 韩冰 卢云 吕振华 刘相萍 《山东医药》 CAS 北大核心 2008年第18期25-26,共2页
目的观察LIGHT、IFN-γ基因转染人肝癌细胞HepG2的凋亡及其Caspase-3和survivin的表达变化。方法用LIGHT、IFN-γ真核细胞表达质粒pcDNA4C-LIGHT-cDNA、pcDNA4C-IFN-γ-cDNA及其转化的E.coliJM-109感受态大肠杆菌,经质粒提取后,转染人... 目的观察LIGHT、IFN-γ基因转染人肝癌细胞HepG2的凋亡及其Caspase-3和survivin的表达变化。方法用LIGHT、IFN-γ真核细胞表达质粒pcDNA4C-LIGHT-cDNA、pcDNA4C-IFN-γ-cDNA及其转化的E.coliJM-109感受态大肠杆菌,经质粒提取后,转染人肝癌细胞HepG2,同时设对照组(未转染)。分别于转染后12、24、48 h收集HepG2细胞。流式细胞仪检测细胞凋亡和Caspase-3、survivin。结果转染后细胞凋亡及Caspase-3表达量在对照组、LIGHT单转组、联合转染组呈逐渐递增趋势,survivin表达量呈递减趋势。结论LIGHT转染后能通过调节HepG2细胞Caspase-3及survivin的表达来发挥促细胞凋亡作用,INF-γ能增强LIGHT诱导的HepG2细胞凋亡,且显著上调其Caspase-3的表达。 展开更多
关键词 IFN-Γ基因 light基因 生存素 半胱氨酸蛋白酶-3 肝肿瘤 HEPG2细胞 细胞凋亡
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STRUCTURE,MOLECULAR WEIGHT AND BIOACTIVITIES OF(1→3)-β-D-GLUCANS AND ITS SULFATED DERIVATIVES FROM FOUR KINDS OF LENTINUS EDODES 被引量:5
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作者 UnursaikhanSurenjav 张俐娜 +3 位作者 Xiao-juanXu MeiZhang PeterChiKeungCheung Fan-boZeng 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2005年第3期327-336,共10页
Lentinan samples,(1→3)-β-D-glucans containing 4.6-15.2 wt% proteins,coded as L-I_1 L-I_2 L-I_3 and L-I_4(L-I)were isolated from four kinds of Lentinus edodes.These glucans were treated with acetone to remove the pro... Lentinan samples,(1→3)-β-D-glucans containing 4.6-15.2 wt% proteins,coded as L-I_1 L-I_2 L-I_3 and L-I_4(L-I)were isolated from four kinds of Lentinus edodes.These glucans were treated with acetone to remove the protein in orderto obtain free protein glucans coded as LNP-I_1,LNP-I_2.LNP-I_3 and LNP-I_4(LNP-I).The free-protein polysaccharideswere sulfated to give derivatives(S-LNP-I)with degree of substitution(DS)from 0.4-0.8.The structural features andweight-average molecular weight(M_w)of the samples were investigated by using infrared spectroscopy,elemental analysis,^(13)C-NMR,size exclusion chromatography combined with laser light scattering(SEC-LLS)and viscometry.The effects ofstructure and conformation of the polysaccharides on antitumor activities were assayed in vivo(Sarcoma 180 solid tumors)and in vitro(Sarcoma 180,HL-60,MCF-7 and Vero tumors).The results indicated that the predominant species of thesamples L-I and LNP-I in 0.2 mol/L NaCl aqueous solution existed as triple-helical chains with high rigidity and in dimethylsulfoxide(DMSO)as single-flexible chains.Interestingly,the antitumor activities of LNP-I are lower than those of the nativeglucans(L-I),whereas their sulfated derivatives have higher inhibition ratio against Sarcoma 180 than LNP-I.The resultsreveal that the binding of protein,sulfated modification and the triple helix conformation are important factors in theenhancement of the antitumor activities of polysaccharides on the whole. 展开更多
关键词 (1→3)-β-D-glucans Lentinus Edodes Molecular weight PROTEIN Sulfated derivative Antitumor activity.
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