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The “Colour Family Drawing Test”: Assessing Children’s Perception of Family Relationships. Studies on Mental Health and Cross-Cultural Comparisons
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作者 Valeria Biasi Paolo Bonaiuto James M. Levin 《Health》 2015年第3期300-307,共8页
We apply the Colour Family Drawing Test, as a development of the traditional black and white test, for cross-cultural comparison. The participants, aged 7 - 10 years, both genders, were examined individually. Each sub... We apply the Colour Family Drawing Test, as a development of the traditional black and white test, for cross-cultural comparison. The participants, aged 7 - 10 years, both genders, were examined individually. Each subject sat at a single table with a white rectangular card of standard size, 24 well-sharpened colour pencils, a black pencil, an eraser and other appropriate tools. S/he received this verbal instruction: “Draw your family”. The procedure was firstly applied to 120 participants attending primary schools of Rome (Biasi, Bonaiuto and Levin, 2014). The families were evaluated through a semi-structural interview conducted with the children’s teachers and divided into: Harmonious versus Very Conflictual Families. The drawings made by children of Harmonious Families consistently used “Reassuring and Playful Colours” (Pink, Orange, Sky Blue, Light Green, Light Yellow, other pastel colours);and were larger, tidier and more proportioned to respect the opposite group. Children belonging to Conflictual Families used mostly “Alarming and Serious Colours” (Grey, Black, Dark Bleu, Violet, Olive Green) and their drawings were less extended, more often disordered and had typical deformations such as figures too thin. A second investigation examined 120 participants belonging to Asian immigrant families residing in Italy. A third investigation examined 120 participants belonging to Russian families of Moscow. Both last two investigations obtained very similar results on the use of colours, and gave a confirmation of the relevance of the Colour Family Drawing Test. 展开更多
关键词 COLOUR Conflictual FAMILY Cross-Cultural Comparison COLOUR drawing FAMILY test EXPRESSIVENESS
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Determination of the Friction Coefficient in the Flat Strip Drawing Test
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作者 Anvar Makhkamov 《Engineering(科研)》 2021年第11期595-604,共10页
Current work is focused on the influence of friction in deep drawing process. Friction measurements were also conducted using a modified tribotester based on strip sliding between tools. Four different tool surfaces w... Current work is focused on the influence of friction in deep drawing process. Friction measurements were also conducted using a modified tribotester based on strip sliding between tools. Four different tool surfaces were tested under similar contact conditions regarding contact area, normal pressure, sliding speed, lubricant and surface characteristics to calculate the friction coefficient between the tool surface and a high strength low alloy steel sheet HSLA 380. The results showed that friction coefficient varies over a wide range with different lubricating conditions and different sliding velocities. For some sliding velocities, the coefficient of friction is stable and low, while for others it is unstable and higher. Results of the experiments reveal that this novel tribotester is a very useful tool to evaluate and compare the friction between steel sheet and tool surfaces in alloyed steel for cold working applications. The outcomes have only small dispersion within the different test series, which indicates a stable process with good repeatability. The test method enables comparison of different surface finishes and treatments, lubricants and coatings in terms of friction and galling under conditions similar to those found in sheet metal forming processes. The four different types of surfaces considered for this study were grinded, polished, nitrided and quenched/tempered. The main difference among the tested tools in this work was the surface roughness, which was found to have a strong influence on friction. 展开更多
关键词 TRIBOLOGY Friction ROUGHNESS Sheet Metal Forming LUBRICANT Steel Sheet Tool Surface Coefficient of Friction Normal Force Sliding Speed Contact Pressure Strip drawing test
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RESEARCH ON THE EVALUATION METHOD OF FRICTION AND LUBRICATION IN DEEP DRAWING 被引量:13
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作者 D.N.He X.F.Yin +4 位作者 H.Z.Thao D.Lv X.Y.Ruan J.L.Cheng J.Y.Jiang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第2期439-445,共7页
The deformation characteristic of bland in deep drawing is discussed. It is pointed out that the friction and lubrication conditions in for drawing are different from that in mechanical motion or machine work or other... The deformation characteristic of bland in deep drawing is discussed. It is pointed out that the friction and lubrication conditions in for drawing are different from that in mechanical motion or machine work or other plastic process. The common test methods in laboratories are analyzed. It shows that though all those test methods can test the friction coefficient, the probe test method is most suitable for the research of friction and lubrication and the process in deep drawing, for this method is identical with the actual work condition either from the test principle or deformation status of the blank. Last the successful application in the deep drawing simulator newly developed the the probe method are intro- duced in detail. 展开更多
关键词 deep drawing probe test method friction and lubrication evaluation method
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Effect of Friction Coefficient on Deep Drawing of 6A16 Aluminum Alloy for Automobile Body 被引量:3
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作者 刘钊扬 熊柏青 +4 位作者 LI Xiwu YAN Lizhen LI Zhihui ZHANG Yongan LIU Hongwei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第1期208-214,共7页
Based on the ABAQUS/Explicit finite element method,the forming force changing trend of deep drawing test for 6A16 aluminum alloy plate after pre-aging and storage at room temperature for one month was simulated under ... Based on the ABAQUS/Explicit finite element method,the forming force changing trend of deep drawing test for 6A16 aluminum alloy plate after pre-aging and storage at room temperature for one month was simulated under friction coefficient ranging from 0 to 0.22.The lubricants selected for the tests were mechanical oil,butter and dry film lubricant,and the friction coefficient of these lubricants were 0.05,0.10 and 0.15,respectively.Microstructural evolution of 6 A16 aluminum alloy plate during drawing forming was investigated by OM,SEM and EBSD.The results showed that,with the increase of friction coefficient,the stress,strain and deformation degree in deformation zone increased,while the grain size in deformation zone decreased.Thus,the hardness of the cup-typed component increased with the increase of friction coefficient.Butter-lubricated cups had the highest tensile strength and yield strength after paint-bake cycle.The combination of simulation results and microstructure analysis of 6A16 aluminum alloy plate after drawing forming indicates that the appropriate lubricant is butter. 展开更多
关键词 FINITE element method 6A16 aluminum alloys deep drawing test FRICTION COEFFICIENT
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Three-dimensional experimental study of loose top-coal drawing law for longwall top-coal caving mining technology 被引量:13
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作者 Jiachen Wang Jinwang Zhang +1 位作者 Zhengyang Song Zhaolong Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第3期318-326,共9页
Based on the loose medium flow field theory, the loose top-coal drawing law of longwall top-coal caving(LTCC) mining technology is studied by using self-developed three-dimensional(3D) test device. The loose top-c... Based on the loose medium flow field theory, the loose top-coal drawing law of longwall top-coal caving(LTCC) mining technology is studied by using self-developed three-dimensional(3D) test device. The loose top-coal drawing test with shields and the controlled test without shields are performed in the condition without any boundary effect. Test results show that shields will cause reduction in drawing volume of coal in the LTCC mining. The deflection phenomenon of drawing body is also observed in the controlled test, which is verified that the deflection of drawing body is caused by shield. It is found that the deflection angle decreases with increasing caving height, with the maximum value of atailand the minimum value of 0. In addition, the formula to calculate the drawing volume is proposed subsequently.The deflection of drawing body is numerically simulated using particle flow code PFC3 Dand the proposed formula to calculate drawing volume in LTCC is also verified. 展开更多
关键词 Longwall top-coal caving(LTCC) Caving shield Three-dimensional(3D) physical model test Deflection of drawing body PFC3D
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Effect of Friction on the Drawing Process of Hot-Galvanized Sheet Steel 被引量:1
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作者 Hongying GONG Wei ZHU +1 位作者 Zhiliang ZHANG Zhenliang LOU 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第4期531-535,共5页
A probe test method was employed to detect the friction condition of the interfaces between tools and blank. At the same time a self-developed measurement apparatus to realize the probe test method was also presented.... A probe test method was employed to detect the friction condition of the interfaces between tools and blank. At the same time a self-developed measurement apparatus to realize the probe test method was also presented. Based on the analysis of force, a correlative friction model was also given. With the self-developed measurement apparatus,the effects of three kinds of lubricating oils which were in common use during the process of sheet steel drawing were studied. By probing the friction coefficient values of different lubricating oils during the drawing process of the hot-galvanized sheet steel (steel brand: ST07Zn), we can see that the friction caused by PK oil was the lowest, so the effect of PK oil was the best. Then PK oil was used as the base lubricating oil and some solid additive powers was added into it to make a new type lubrication (named as L oil).The result of test proved that the new lubricating oil had remarkable effect on the drawing process of hot-galvanized sheet steel. 展开更多
关键词 drawing process FRICTION Probe test method Hot-galvanlzed sheet steel
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The Effectiveness of Clinical Colloquium Established by the “Drawing Recall” Technique in University Counselling Services for Student Mental Health
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作者 Valeria Biasi Paolo Bonaiuto +1 位作者 Nazarena Patrizi James M. Levin 《Health》 2015年第5期521-532,共12页
An experimental assessment of the effectiveness of university counselling was conducted through the “Stress Drawing Recall” Technique applied before and after a clinical colloquium with 70 university students of bot... An experimental assessment of the effectiveness of university counselling was conducted through the “Stress Drawing Recall” Technique applied before and after a clinical colloquium with 70 university students of both genders, aged 18 - 35 years, who had requested this service. Another 70 students waiting to undergo the colloquium were interviewed as a control group. Two parallel series of drawings depicting personal stress situations were collected and, after evaluation by three expert judges in “double-blind” conditions, led to establishing five forms of development of the graphic language from the first to second drawing, defined as follows: a) distension, with a reduction in stress indicators and increase in comfort indicators;b) explicit representation of conflict resolution;c) appearance of new elements, with persisting conflict;d) increase in stress indicators;e) invariant or equivalent repetition of the stress drawing. Results showed that students who underwent the clinical colloquium (experimental group) changed their stress drawings mainly in the direction of distension and conflict resolution, while the control group had more invariant or equivalent repetition of the stress situation (?= 62.77;p < 0.001). The events depicted in the stress drawings were divided into three categories: a) limited short-term stressful situations due to mainly external agents;b) externally induced stressful situations with intense emotional resonance;c) wide-ranging long-lasting stressful situations with great involvement of the self. The participants were divided into: a) very anxious subjects;b) averagely anxious subjects;c) not very anxious subjects, on the basis of their scores on two questionnaires: the MPI (1959) and the STAI (1970). There is a correspondence between the subjects’ level of conflict and extension of the depicted stress. This confirms the usefulness of the Stress Drawing Recall Technique in psychological counselling. 展开更多
关键词 Assessment CLINICAL COLLOQUIUM COUNSELLING Service drawing RECALL TECHNIQUE Personality test
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Mouse-Sensitive Following Path Suggestion for Drawing Travel Routes in Web Map Systems
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作者 Pablo Martinez Lerin Daisuke Yamamoto Naohisa Takahashi 《Journal of Geographic Information System》 2012年第5期393-402,共10页
This paper proposes a web map system for drawing an arbitrary travel route using a mouse-sensitive following path suggestion. The interaction model of the system allows users to intuitively understand the sequence of ... This paper proposes a web map system for drawing an arbitrary travel route using a mouse-sensitive following path suggestion. The interaction model of the system allows users to intuitively understand the sequence of user actions needed to draw a conceived route and reduces the number of user actions required. Moreover, the system allows users to understand at a glance several drawing alternatives (static suggestion) and also consider a particular drawing alternative (dynamic suggestion) without making any commitment. The proposed architecture of the system reduces the influence caused by communication delay between a map server and a web client by delivering in advance road network data from a map server to a web client. Experimental evaluations on a prototype we developed demonstrated that the proposed system enables users to draw arbitrary routes within noticeably less clicks, in less time, and with less stress than previous systems. 展开更多
关键词 computer-aided ROUTE drawing FOLLOWING PATH Web Map System GIS
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Computer-Aided Design of X-Ray Microtomographic Scanners
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作者 V. I. Syryamkin E. N. Bogomolov +3 位作者 V. V. Brazovsky A. Sh. Bureev G. S. Glushkov A. V. Vasiliev 《Advances in Computed Tomography》 2013年第3期83-90,共8页
The article is to study the development of computer-aided design of X-ray microtomography—the device for investigating the structure and construction of three-dimensional images of organic and inorganic objects on th... The article is to study the development of computer-aided design of X-ray microtomography—the device for investigating the structure and construction of three-dimensional images of organic and inorganic objects on the basis of shadow projections. This article provides basic information regarding CAD of X-ray microtomography and a scheme consisting of three levels. The article also shows basic relations of X-ray computed tomography, the generalized scheme of an X-ray microtomographic scanner. The methods of X-ray imaging of the spatial microstructure and morphometry of materials are described. The main characteristics of an X-ray microtomographic scanner, the X-ray source, X-ray optical elements and mechanical components of the positioning system are shown. The block scheme and software functional scheme for intelligent neural network system of analysis of the internal microstructure of objects are presented. The method of choice of design parameters of CAD of X-ray microtomography aims at improving the quality of design and reducing costs of it. It is supposed to reduce the design time and eliminate the growing number of engineers involved in development and construction of X-ray microtomographic scanners. 展开更多
关键词 TOMOGRAPHY Microtomography NON-DESTRUCTIVE testing DIAGNOSIS X-RAY Microtomographic SCANNER X-RAY Optical Systems Mechatronic System computer-aided Design
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Critical Analysis of Children’s Drawings as a Diagnostic Tool for Body Schema and Body Image Disorder in Cerebral Palsy
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作者 Renée Lampe Ines Lützow +2 位作者 Tobias Blumenstein Varvara Turova Ana Alves-Pinto 《Neuroscience & Medicine》 2016年第4期133-148,共16页
Cerebral palsy is a multiple disability manifested by motor deficits and impairments of cognition, language, and body perception. To assess if body schema and body image distortion in children and youth with cerebral ... Cerebral palsy is a multiple disability manifested by motor deficits and impairments of cognition, language, and body perception. To assess if body schema and body image distortion in children and youth with cerebral palsy can be represented through draw-a-person-test, outcome measure of conscious and subconscious body awareness, visual perception and cognition in two age-matched groups, one with cerebral palsy and other with developmental disability, were collected. The outcome was compared within the two groups and with reference data (healthy population) and correlated with the outcome of draw-a-person test. Decreased scores in the draw-a-person test in subjects with cerebral palsy compared both to subjects with developmental disorders and to healthy population had strongly correlated with decreased scores in visual perception. This suggests that draw-a-person test may provide a preliminary guidance for the assessment of visual perception. No statistically significant effect of cognitive abilities on performance in the draw-a-person test was found. The influence of both conscious and subconscious body awareness on the scores in the draw-a-person test was not significant, which confirms that this test alone is not fully reliable to detect the body schema and body image disorder in cerebral palsy. 展开更多
关键词 Cerebral Palsy draw-a-Person-test Body Perception Body Representation Disorder
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基于图像分类的自动绘画心理分析方法
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作者 赵小明 潘婷 刘伟锋 《计算机与现代化》 2024年第8期92-97,共6页
绘画心理分析广泛应用于心理问题的发现和精神障碍的治疗中。房树人测试是最具代表性的绘画心理分析方法,通过画者绘制的房屋、树木和人物,投射个体的心理状态。相比于问卷式心理筛查,房树人测试具有非语言性、投射性、创造性等优势,能... 绘画心理分析广泛应用于心理问题的发现和精神障碍的治疗中。房树人测试是最具代表性的绘画心理分析方法,通过画者绘制的房屋、树木和人物,投射个体的心理状态。相比于问卷式心理筛查,房树人测试具有非语言性、投射性、创造性等优势,能有效地突破被测者的心理防御。目前,房树人测试是由咨询师实施并进行评定,在大规模的心理筛查中耗时较长,而且评定结果会受到咨询师的经验和主观性的影响。因此,建立一种自动化方法来提高房树人测试的客观性、可靠性和效率是必要的。本文基于心理状态和绘画特征之间的关系提出一种自动的房树人测试绘画筛查方法。本文提取画面的面积、位置、阴影等关键特征,并将这些特征组合构建绘画分类器。该方法可有效地筛查出负向绘画,以便进一步地诊断和治疗。同时本文收集来自高校心理咨询中心的房树人测试绘画并制作房树人数据集以进行实验,实验结果表明了该方法的优越性和应用价值。 展开更多
关键词 图像分类 特征提取 绘画心理分析 房树人测试
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钢-连续纤维复合筋珊瑚混凝土梁式拉拔粘结应力分布研究
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作者 王磊 余涵 +3 位作者 章明明 谷健 卢家慧 朱得祥 《硅酸盐通报》 CAS 北大核心 2024年第7期2461-2469,2489,共10页
为探究钢-连续纤维复合筋(SFCB)在珊瑚混凝土中的粘结应力分布,使用梁式拉拔试验方法,对碳纤维增强复合材料(CFRP)筋和不同直径SFCB珊瑚混凝土进行拉拔,并采用光纤Bragg光栅(FBG)传感技术对筋材应力分布变化动态监测。研究结果表明:SFC... 为探究钢-连续纤维复合筋(SFCB)在珊瑚混凝土中的粘结应力分布,使用梁式拉拔试验方法,对碳纤维增强复合材料(CFRP)筋和不同直径SFCB珊瑚混凝土进行拉拔,并采用光纤Bragg光栅(FBG)传感技术对筋材应力分布变化动态监测。研究结果表明:SFCB直径和钢芯直径均会影响荷载-滑移曲线形状;箍筋对筋材初始粘结刚度和SFCB纤维层加载端应变有明显提升;箍筋一定程度可以增强螺纹钢芯的粘结,对光圆钢芯粘结影响不大;SFCB屈服后的粘结应力分布与屈服前有明显差异,钢芯屈服后应力传递现象更明显;由于钢芯具有较高的弹性模量,在相同荷载下SFCB纤维层粘结段各处粘结应力均要大于CFRP筋。 展开更多
关键词 SFCB 珊瑚混凝土 梁式拉拔试验 粘结应力分布 SFCB应变 光纤光栅传感技术
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发泡水对泡沫沥青粘聚/粘附性的多尺度影响研究 被引量:1
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作者 周培研 刘圣洁 +1 位作者 李晓超 曾俐豪 《应用化工》 CAS CSCD 北大核心 2024年第2期257-261,共5页
综合采用分子动力学模拟、水煮法实验、表面自由能实验和拉拔实验等宏微观方法,研究发泡水对沥青粘聚和粘附性的影响机制。结果表明,分子尺度上水分子排斥沥青分子,从而削弱沥青间界面能量;宏观尺度发现泡沫沥青与集料的抗水煮剥落性有... 综合采用分子动力学模拟、水煮法实验、表面自由能实验和拉拔实验等宏微观方法,研究发泡水对沥青粘聚和粘附性的影响机制。结果表明,分子尺度上水分子排斥沥青分子,从而削弱沥青间界面能量;宏观尺度发现泡沫沥青与集料的抗水煮剥落性有所降低,发泡水对沥青的粘聚及粘附性不利,且发泡水越多对沥青的粘聚和粘附性损害越明显。泡沫沥青界面能与其粘聚和粘附性能具有高度相关性,可从宏观尺度和微观分子尺度解释发泡水对泡沫沥青粘聚/粘附性的多尺度影响。 展开更多
关键词 泡沫沥青 分子模拟 水煮法实验 表面自由能实验 拉拔实验
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U型框类零件双向拉深成形研究 被引量:1
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作者 雷青哲 王悉颖 +3 位作者 姜涛 周健 段崇 翟攀 《塑性工程学报》 CAS CSCD 北大核心 2024年第1期118-125,共8页
针对U型框类零件成形质量不稳定、修整手工量大等问题,通过对零件结构的分析研究,借助CATIA对其进行了工艺补充面设计,并借助数值模拟对成形过程进行了仿真,研究了双向拉深成形工艺,设计了一种特有传力方式的双向拉深模具结构;选取凸凹... 针对U型框类零件成形质量不稳定、修整手工量大等问题,通过对零件结构的分析研究,借助CATIA对其进行了工艺补充面设计,并借助数值模拟对成形过程进行了仿真,研究了双向拉深成形工艺,设计了一种特有传力方式的双向拉深模具结构;选取凸凹模间隙、摩擦因数、压边力及拉深速度4个因素为优化变量,通过正交试验得出最优工艺参数组合,即压边力大小为30 kN、摩擦因数为0.1、凸凹模间隙为1.6 mm、拉深速度为6000 mm·s^(-1);最后针对拉深后回弹现象,对校正模进行了分析和设计并修整。生产试验表明,此模具结构可以很好地改善零件成形质量,提高效率并满足生产及设计要求。 展开更多
关键词 U型框类零件 数值模拟 双向拉深成形 正交试验 拉深模
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启蒙视域下数字孪生技术在机械制图课程中的实践研究
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作者 徐丹凤 陈冰 《农机使用与维修》 2024年第3期132-134,共3页
数字孪生技术通过数学建模和仿真,将真实物理系统与数字技术相结合,以实现系统的监测、分析和优化。机械制图课程强调理论与实践的结合,是一门互动性和实验性较强的综合性课程。该文基于数字孪生技术对机械制图课程教学模式及教学方法... 数字孪生技术通过数学建模和仿真,将真实物理系统与数字技术相结合,以实现系统的监测、分析和优化。机械制图课程强调理论与实践的结合,是一门互动性和实验性较强的综合性课程。该文基于数字孪生技术对机械制图课程教学模式及教学方法进行优化,通过模拟和仿真,学生可以观察不同因素对系统行为的影响,从而更深入地了解机械工程的基本原理,这种教学模式可以激发学生的创造力,使其更加积极地参与课程。通过实践测试可知,优化后的教学模式可以有效提高学生的学习体验和教育效果。 展开更多
关键词 数字孪生技术 机械制图 机械工程教育 理论知识 测试
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全轻页岩陶粒混凝土与钢筋的极限粘接强度影响研究
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作者 贾虹 李绥波 《粘接》 CAS 2024年第2期42-45,共4页
全轻页岩陶粒混凝土和钢筋之间的粘接作用较为复杂,粘接强度受钢筋类型、锚固长度、混凝土强度等因素影响,通常采用中心拉拔试验方法分析全轻页岩陶粒混凝土的粘接效果。对此,采用该方法进行了12组不同标准的全轻页岩陶粒钢筋混凝土试... 全轻页岩陶粒混凝土和钢筋之间的粘接作用较为复杂,粘接强度受钢筋类型、锚固长度、混凝土强度等因素影响,通常采用中心拉拔试验方法分析全轻页岩陶粒混凝土的粘接效果。对此,采用该方法进行了12组不同标准的全轻页岩陶粒钢筋混凝土试件粘接强度测试试验,分析了试件拉拔破坏和劈裂破坏二种破坏形态,对比了不同钢筋直径、钢筋类型和混凝土强度等级下试件的粘接强度变化,并提出了更加合理的极限粘接强度计算方式。以期促进全轻页岩陶粒混凝土的深入研究和在建筑行业的广泛应用。 展开更多
关键词 全轻页岩陶粒混凝土 钢筋 中心拉拔试验 粘接强度 计算方式
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基于改进YOLOv7⁃tiny的画钟测验识别
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作者 温远寒 曹娜 +2 位作者 刘怡欣 何小海 滕奇志 《现代计算机》 2024年第3期18-25,共8页
画钟测验是筛查认知障碍人群的一种重要医学手段。针对目前画钟测验中存在目标尺度不同和类别不平衡的问题,提出一种基于改进YOLOv7⁃tiny的画钟测验识别算法。为改善尺度变化和小尺度目标检测带来的错检漏检问题,引入BiFPN双向特征金字... 画钟测验是筛查认知障碍人群的一种重要医学手段。针对目前画钟测验中存在目标尺度不同和类别不平衡的问题,提出一种基于改进YOLOv7⁃tiny的画钟测验识别算法。为改善尺度变化和小尺度目标检测带来的错检漏检问题,引入BiFPN双向特征金字塔结构,双向信息传递机制可有效融合不同层级特征,捕捉不同尺度特征中更丰富的上下文和细节信息。为提升类别不平衡指标的识别准确度,采用WDLoss损失函数计算损失提高小目标识别敏感性。此外还创建了一个基于认知障碍群体的画钟测验数据集,在此数据集上实验表明,改进后YOLOv7⁃tiny算法对画钟测验数据集所有类别的mAP为94.28%,相比于原YOLOv7⁃tiny模型提高了1.13%,不均衡类别中指针的AP提高了12.2%。 展开更多
关键词 画钟测验 YOLOv7⁃tiny BiFPN WDLoss
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Automatic Control of Automobile Transmission Performance Test Stand
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作者 阎清东 项昌乐 冯永存 《Journal of Beijing Institute of Technology》 EI CAS 1998年第2期178-183,共6页
To realize automatic control of automobile transmission performance test stand Methods The automatic control technique of the lubricant temperature,the program- controll- edautomaticshifting of the transmission,the c... To realize automatic control of automobile transmission performance test stand Methods The automatic control technique of the lubricant temperature,the program- controll- edautomaticshifting of the transmission,the continuous adjusting of revolution speed and load, data-acquisition and data real-time processing were adopted.Results The lubricant temperature was controlled at the set temperature ±2℃.The automatic shifting of the trans- mission is simple,reliable and accurate.The automatic adjusting of load and rotation speed is rapidandaccurate,the torque divergence is ±1N·m,the rotation speed divergence is ±5r/min Conclusion The four kinds of techniques are applied into the automobile transmission perfor- mance test stand successfully. mancetest stand successfully. 展开更多
关键词 automobile transmission performance test computer-aided test automatic control
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汽车前车门加强板冲压工艺设计及成形优化
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作者 万志远 倪传东 《塑性工程学报》 CAS CSCD 北大核心 2024年第7期71-77,共7页
针对汽车前车门加强板变形复杂、材料流动不易控制、成形开裂等问题,首先分析了汽车前车门加强板结构特点,确定了“一模两件”的总体成形方案,并详细设计了拉延成形、修边-冲孔-整形、修边-侧冲和侧修边-侧冲孔-冲孔-切断的成形过程。... 针对汽车前车门加强板变形复杂、材料流动不易控制、成形开裂等问题,首先分析了汽车前车门加强板结构特点,确定了“一模两件”的总体成形方案,并详细设计了拉延成形、修边-冲孔-整形、修边-侧冲和侧修边-侧冲孔-冲孔-切断的成形过程。其次以材料减薄率为切入点,采用数值模拟探究了压边力、模具间隙和冲压速率对零件成形质量的影响规律,预测了零件开裂的位置和程度,得到了较为优异的工艺参数:压边力控制在400 kN以内,模具间隙不小于1.10 mm,冲压速率不高于3000 mm·s^(-1)。最后采用正交试验方法,得到了各因素各水平最大减薄率平均值,计算出压边力、模具间隙和冲压速率这三者的极差分别为3.223%、1.489%和0.763%。基于分析结果得到了压边力300 kN,模具间隙1.15 mm,冲压速率3000 mm·s^(-1)的最优工艺参数组合,并进行了生产试验验证,制出了合格成形零件实物。 展开更多
关键词 前车门加强板 工艺设计 最大减薄率 拉深模 正交试验
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影响POY动态热应力测试因素的探讨
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作者 周丹 《合成纤维》 CAS 2024年第6期16-18,共3页
采用YG367型全自动长丝热应力测试仪探究试验速度、牵伸比、加热箱温度等因素对预取向丝(POY)动态热应力的影响。试验结果表明:在50~150 m/min的试验速度范围内,试验速度对POY动态热应力并无太大影响;在150~250 m/min试验速度之间,POY... 采用YG367型全自动长丝热应力测试仪探究试验速度、牵伸比、加热箱温度等因素对预取向丝(POY)动态热应力的影响。试验结果表明:在50~150 m/min的试验速度范围内,试验速度对POY动态热应力并无太大影响;在150~250 m/min试验速度之间,POY动态热应力随着试验速度的增加而变大;牵伸比为1.60、1.65、1.70时,POY动态热应力随着牵伸比的增大而增大,成正比关系;加热箱温度对POY动态热应力也有一定的影响,但无明显规律,因此加热箱温度选定后不要轻易改变。 展开更多
关键词 POY 动态热应力 试验速度 牵伸比 加热箱温度
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