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排序方式: 共有396条查询结果,搜索用时 15 毫秒
31.
介绍了某重卡调整线运用IE手法,引入工业工程中的作业分析、程序分析、作业分析、动作分析等方法和思想,对生产线进行改善。 相似文献
32.
Yu Sik Kong Jiyoung Yu Young Whan Park 《International Journal of Automotive Technology》2018,19(6):1055-1059
This study was carried out to investigate the creep life at the high temperature of the Alloy 718 for automotive engine components using the initial strain parameter method (ISPM). Creep tests have performed at elevated temperatures in the range of 550 oC to 700 oC in this work. We also carried out constant stress creep tests. The initial strains were measured during 1 minute after loading. Both the creep stress and rupture time depend on the initial strain. We calculated the creep life of Alloy 718 by using the creep life prediction equations obtained from the ISPM. Then, we compared the creep life predicted by the ISPM to the Larson-Miller parameter (LMP). The experimental rupture time and the calculated rupture time by using the ISPM agreed with a confidence level of 95 %. The creep life predicted by using the ISPM was in very good agreement with the creep life predicted using the LMP method. 相似文献
33.
To evaluate the clinical outcome, effectiveness and safety of the surgical management of traumatic lumbar spondylolisthesis
with transforaminal lumbar interbody fusion (TLIF) with short segmental instrumentation fixation. A retrospective review of
a consecutive series of 24 patients with traumatic lumbar spondylolisthesis treated with TLIF procedure was carried out. Intraoperative
spinal cord monitoring was used to confirm the peripheral neural function intact during the reduction of the spondylolisthesis.
Preoperative clinical and radiographic evaluation of all cases were originally collected prospectively. Data regarding blood
loss, operative time, duration of hospital stay, radiographic fusion, instrumentation failure and clinical result were collected
and observed at regular follow-up periods. All patients were engaged in high-energy accidents in the lower back and 16 patients
had concomitant injuries. The mean operative time was 124 min, mean blood loss was 350 mL, and mean hospital stay was 6.5
days. There were no complications such as incision infection, cerebrospinal fluide (CSF) leakage and nerve root injury and
so on. All patients demonstrated a solid lumbar interbody fusion within 4 months, and no evidence of spondylolisthesis correction
loss, instrumentation failure and loosing. They all were completely asymptomatic, with normal neurologic findings, and had
resumed their previous level of physical activities on the final follow-up. Meticulous clinical examination and careful imaging
assessment could assist an early diagonosis in cases of traumatic lumbar spondylolisthesis. Performing open reduction and
the TLIF procedure as soon as possible could restore segmental stability and painless function. The TLIF procedure was a safe,
effective technique to treat traumatic lumbar spondylolisthesis. 相似文献
34.
结合施桥三线船闸工程实例,从质量目标的确立,质量保证体系的建立等方面分析构建质量目标的实现路径,探讨工程质量的过程监控,创优载体的设立以及环境的营造等,以促进船闸工程的全面创优。 相似文献
35.
根据城市公交车的工作特点,对串联式混合动力公交车动力系统主要部件发动机、电动机、电池组等,提出了选择和设计原则,实现优化匹配,提高动力性、燃油经济性以及降低排放性能. 相似文献
36.
概述了重点码头防护体系构建原则,提出了信息化战争重点码头防护体系建设构想,以组织指挥体制、防护力量建设体系、技术储备体系、物质储备体系、一体化防护体系为内容构建重点码头防护体系,对于有效应对敌打击破坏、提高战时码头的生存能力有重要意义. 相似文献
37.
This paper presents a full-scale solution to the detection of the traffic data using laser device. Range images, gathered
by a particular laser camera, are used in the multi-threshold segmentation. The multi-threshold segmentation is based on the
height of the moving objects. In order to get the precise height of the moving objects, mapping of the original terrain is
performed on the first step. On each layer, the clustering algorithm called iteration-self organizing data analysis techniques
algorithm (ISODATA) is conducted afterwards. Kalman filtering technique is applied to recognize and track the moving objects.
Extensive experiments show that these algorithms are effective in object recognition and tracking, as well as robust in the
applications. 相似文献
38.
For the task of visual-based automatic product image classification for e-commerce, this paper constructs a set of support
vector machine (SVM) classifiers with different model representations. Each base SVM classifier is trained with either different
types of features or different spatial levels. The probability outputs of these SVM classifiers are concatenated into feature
vectors for training another SVM classifier with a Gaussian radial basis function (RBF) kernel. This scheme achieves state-of-the-art
average accuracy of 86.9% for product image classification on the public product dataset PI 100. 相似文献
39.
自振特性是反映桥梁动力特性的主要模态参数,包括自振频率和振型,反映出桥梁的刚度指标,是评价桥梁动力性能的主要依据。文中采用MIDAS有限元程序,建立跨径为132m的钢管混凝土系杆拱桥三维空间模型,对全桥开展动力特性分析,并通过脉动试验对理论分析进行校核,结果表明实测值与理论计算值吻合良好。 相似文献
40.
Phase change analysis of an underwater glider propelled by the ocean's thermal energy 总被引:1,自引:0,他引:1
KONG Qiao-ling MA Jie 《船舶与海洋工程学报》2007,6(4):37-43
The phase change characteristic of the power source of an underwater glider propelled by the ocean's thermal energy is the key factor in glider attitude control. A numerical model has been established based on the enthalpy method to analyze the phase change heat transfer process under convective boundary conditions. Phase change is not an isothermal process, but one that occurs at a range of temperature. The total melting time of the material is very sensitive to the surrounding temperature. When the temperature of the surroundings decreases 8 degrees, the total melting time increases 1.8 times. But variations in surrounding temperature have little effect on the initial temperature of phase change, and the slope of the temperature time history curve remains the same. However, the temperature at which phase change is completed decreases significantly. Our research shows that the phase change process is also affected by container size, boundary conditions, and the power source's cross sectional area. Materials stored in 3 cylindrical containers with a diameter of 38ram needed the shortest phase change time. Our conclusions should be helpful in effective design of underwater glider power systems. 相似文献