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111.
实施开放式实验教学已成为当前高校实验教学改革的突破口。实施开放式实验教学,必须构建科学的运行体系,主要包括教学目标体系、内容体系、保障体系和效能考评体系四个方面。  相似文献   
112.
工业锅炉热效率测试方法与实践   总被引:1,自引:1,他引:0  
本从测试原理、测试仪器及测试计算等方面系统介绍了利用ENERAC942-XP型燃烧效率计算机测试工业锅炉效率的一种方法。  相似文献   
113.
通过对河口探区内370口已经核销的老探井进行重新评价,认为受地质认识和采油工艺局限性的影响有21口已经核销的老探井初次试油不彻底。随着地质认识的不断完善和采油工艺的不断改进,对其中的17口井进行了重新试油均获得成功,产油量由8.94t/d增加到73.9t/d,新增探明石油地质储量6063×104t。实施核销探井再评价,不仅深化了地质认识,盘活了闲置资产,缩短了增储周期,降低了勘探成本,而且通过出油井点的突破,找到了一条高勘探成熟地区油气勘探的路子。  相似文献   
114.
B. Zhao  G.S. Mittal 《LWT》2007,40(4):655-660
Ultrasound backscattered signals for object detection could be too weak to be perceived when superposed to strong reflection signals, and could also be complicated either in time or frequency domain. These peculiarities raise a challenge for signal processing methods. In this paper four signal processing methods were studied to detect objects in containers. Root mean squares (RMS) method was better in object detection but needed to combine other methods to increase detection success rate. Variance, center frequency pressure ratio (CFPR) and backscattered amplitude integral (BAI) methods have similar overall detection ratings. The optimal signal size, to increase the detection ability, corresponded approximately to the length of reverberation signals before it was dissipated.  相似文献   
115.
When modern saloon cars are re-engineered as convertibles (or roadsters) it is typical for them to lose 50% or more of the body’s torsional rigidity. Consequently the vehicles rarely handle quite as crisply, nor do they ride as well as the coupes from which they derived. This paper highlights the fundamental contributions of advanced composites in achieving the desired value of handling of the Murcièlago Roadster without penalizing the overall weight of the vehicle. To compensate for the absence of the roof structure, the vehicle was strongly redesigned by introducing new structural members and reinforcing existing critical components. A new all-carbon/epoxy composite sub-frame, which spans the entire engine bay, is comprised of elliptical tubular members, and it is the first of its kind in a production vehicle. Engineering of the sub-frame, from preliminary design to manufacturing decisions, is the focus of this paper, and is achieved through a Building Block approach that sets the program within the Integrated Product Development (IPD) strategy that the Advanced Composites Division of Automobili Lamborghini S.p.A. employs for its technology demonstrators. The strategy consists in a concurrent analytical and experimental development of the product, from the initial conceptual design and coupon testing, through the stages of element and subcomponent engineering, to final component manufacturing.  相似文献   
116.
超声-回弹-钻芯综合法测强初探   总被引:3,自引:0,他引:3  
基于超声-回弹综合法和钻芯法检测结构混凝土强度的原理及优缺点分析,对采用超声-回弹综合法和钻芯取样法联合测强的方法:超声-回弹-钻芯综合法进行了理论研究,并结合统计理论给出了其中相关参数的确定方法。工程实例证明,该测试方法费用合理、损伤较小,且结果可靠、精度高、可在桥梁、基础等工程中推广应用。  相似文献   
117.
许家新 《油气井测试》2003,12(4):20-22,35
经对冷43块深层块状普通稠油水驱注水5个试验井组开展的稳定同位素示踪测试,利用中子活化技术分析样品,采用先进的示踪剂定量分析与流动模拟相互结合的方法,以示踪数值模拟为手段,评价了油井连通、油层平面及纵向上的非均质性、隔层的封隔性等因素对水驱控制程度及动用状况的影响,通过优化注水推进方向及速度,强化动态调整措施,提高了稳产基础。  相似文献   
118.
I. Aidos    N. Kreb    M. Boonman    J.B. Luten    R.M. Boom    A. Van  Der Padt 《Journal of food science》2003,68(2):581-586
ABSTRACT: A pilot plant used for upgrading herring byproducts into fish oil was analyzed on its operational efficiency and product quality. The temperature of the heat exchanger and the speeds of the pump and the 3-phase decanter were varied according to a 23 fractional factorial design. The initial amount of oxidation products present in the crude oil, its storage stability, and the yields from the different obtained products were determined. Multivariate data analysis of the advanced screening stage showed that T had neither influence on the quality nor on the yield in contrast to D and MP (P < 0.05). Process optimization results showed that the quality of the oil was influenced by an interaction effect between the speed of the MP and the D. Oils processed with the highest MP speed were the most stable during storage.  相似文献   
119.
简要介绍了漏磁探伤的基本原理及工艺流程与设备仪器,并对油管的常见损伤缺陷进行了分析。  相似文献   
120.
The primary aim of this paper is to present results describing in detail the behaviour of ±45° E-glass/MY750 (GRP) tubes, of various wall thicknesses, subjected to equal biaxial tension–compression loading, generated under combined internal pressure and axial compression. The role played by the non-linear lamina shear has also been assessed by comparing various shear stress–strain curves for embedded laminae (extracted from tests on ±45° tubes subjected to circumferential: axial stress ratios SR=1:0, 1:−1 and 2.3:−1) with that of an ‘isolated’ lamina (measured from torsion of 90° tubes). Extracted shear failure strains, for embedded laminae, were more than four fold larger than those measured at ultimate failure for an ‘isolated’ lamina. Soft characteristics were observed in the embedded lamina and these were believed to be due to interaction between early matrix damage initiation (and propagation) and shear. Factors affecting the behaviour of the tubes, such as bulging, scissoring, thermal stresses and stress variation through the thickness are discussed.  相似文献   
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