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In early 2000,large domestic shipyards introduced shipbuilding 3D computer-aided design (CAD) to the hull production design process to define manufacturing and assembly information.The production design process accounts for most of the man-hours (M/H) of the entire design process and is closely connected to yard production because designs must take into account the production schedule of the shipyard,the current state of the dock needed to mount the ship’s block,and supply information.Therefore,many shipyards are investigating the complete automation of the production design process to reduce the M/H for designers.However,these problems are still currently unresolved,and a clear direction is needed for research on the automatic design base of manufacturing rules,batches reflecting changed building specifications,batch updates of boundary information for hull members,and management of the hull model change history to automate the production design process.In this study,a process was developed to aid production design engineers in designing a new ship’s hull block model from that of a similar ship previously built,based on AVEVA Marine.An automation system that uses the similar ship’s hull block model is proposed to reduce M/H and human errors by the production design engineer.First,scheme files holding important information were constructed in a database to automatically update hull block model modifications.Second,for batch updates,the database’s table,including building specifications and the referential integrity of a relational database were compared.In particular,this study focused on reflecting the frequent modification of building specifications and regeneration of boundary information of the adjacent panel due to changes in a specific panel.Third,the rollback function is proposed in which the database (DB) is used to return to the previously designed panels.  相似文献   
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OH  GA 王刚 《轧钢》1991,(Z2):1-5
由于板带材对尺寸公差、表面和组织结构要求很严,因而对锻钢轧辊的质量要求越来越高。锻钢轧辊的质量还直接影响着轧机的生产率和成材率。高速、高轧制力更对锻钢轧辊提出了新的要求。此外,许多轧材用  相似文献   
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Diabetic nephropathy (DN) is a serious kidney complication of diabetes, and constitutes the leading cause of end-stage renal disease. The earliest clinical evidence of DN is microalbuminuria, a term which refers to the appearance of small but abnormal amounts of albumin in the urine. However, screening methods for DN, such as biomarker assays, are yet to be developed for type 2 DN. In the present study, in an attempt to identify the biomarkers for initial diagnoses of type 2 DN, the protein profiles of human sera collected from 30 microalbuminuric type 2 diabetic patients were compared with those collected from 30 normoalbuminuric type 2 diabetic patients, via 2-DE. As a result, a total of 18 spots were determined to have different protein levels in the microalbuminuric patients. Twelve spots had lower protein levels of approximately 50%, and the other six had higher levels of approximately 100-300% as compared to the spots of normoalbuminuric patients. These spots were identified with ESI-Q-TOF (ESI-quadrupole-TOF) MS. Among the identified proteins, vitamin D-binding protein (DBP) and pigment epithelium-derived factor (PEDF) were verified by Western blotting. The results of this study indicate that the DBP may be employed as diagnostic and monitoring biomarkers of type 2 DN, contingent on further study into the matter.  相似文献   
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An electrodeless conductivity probe has been designed and tested at temperatures up to 250 degrees C and pressures of 4.13 MPa (600 psi). A unique pressure seal permits temperature cycling. Design of the electronics permits accurate measurement of conductivities at various elevated temperatures in spite of the change of magnetic properties of the toroids with temperature. The design of the probe can be adapted for insertion, in-line, or bypass operation.  相似文献   
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本文介绍了原苏联暨今俄罗斯自1968年开始研制和使用聚能药包的简单沿革,批量产品的技术性能,使用情况和存在问题,论证了现代化聚能药包的基本方向,并据此进行了改进,对改进型聚以药包的结构原理、规格性能和加工技术条件作了说明;改进型聚能药包已在斯托伊连采选公司和“沃兹涅先卡”露天矿进行了验收工业试验;建议批量生产ЗКП-M和ЗДП型聚能药包。  相似文献   
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在砷化镓(GaAs)集成无源器件(Integrated Passive Device, IPD)的制作工艺中,通孔刻蚀是一道重要环节。蚀刻孔边缘的GaAs会被蚀刻,由此引发崩边并对器件性能及可靠性造成不利影响。本文中,用于通孔蚀刻的GaAs厚度不小于200 μm,通孔边缘没有被蚀刻的痕迹,以实现金属导线的平滑连接。采用光阻和金属来充当掩膜,有效解决了单一光阻因厚度过高而变形或者厚度薄导致GaAs衬底被蚀刻的问题。通过优化工艺,在光阻厚度为32 μm、金属掩膜厚度为0.5 μm、金属蚀刻时间为60 s以及感应耦合等离子体(Inductively Couple Plasma, ICP)蚀刻4000 s的条件下,得到了孔深为200 μm且通孔边缘平整的形貌。分析了 GaAs 崩边形成的主要原因与机理,并通过优化工艺解决了200 μm通孔的崩边问题,从而提高了器件性能及可靠性。  相似文献   
9.
A simplified sample pretreatment method for industrially PAH-contaminated soils applying automated Soxhlet (Soxtherm) with ethyl acetate as extraction solvent is presented. Laborious pretreatment steps such as drying of samples, cleanup of crude extracts, and solvent exchange were allowed to be bypassed without notable performance impact. Moisture of the soil samples did not significantly influence recoveries of PAHs at a wide range of water content for the newly developed method. However, the opposite was true for the standard procedure using the more apolar 1:1 (v/v) n-hexane/acetone solvent mixture including postextraction treatments recommended by the U.S. EPA. Moreover, ethyl acetate crude extracts did not appreciably effect the chromatographic performance (HPLC-(3D)FLD), which was confirmed by a comparison of the purity of PAH spectra from both pretreatment methods. Up to 20% (v/v) in acetonitrile, ethyl acetate proved to be fully compatible with the mobile phase of the HPLC whereas the same concentration of n-hexane/acetone in acetonitrile resulted in significant retention time shifts. The newly developed pretreatment method was applied to three historically contaminated soils from different sources with extraction efficiencies not being significantly different compared to the standard procedure. Finally, the certified reference soil CRM 524 was subjected to the simplified procedure resulting in quantitative recoveries (>92%) for all PAHs analyzed.  相似文献   
10.
Capillary electrochromatography using a specialty monolithic matrix was utilized in developing a rapid and highly efficient separation of isoflavones in biological materials. Without a preconcentration technique, it is relatively easy to reach ppm-ppb concentrations of these compounds in soy-based foods and verify them structurally using a photodiode array detector. With on-column preconcentration, we were able to measure low-ppb levels in human serum. Using blood samples from human volunteers, whose diet was supplemented by a soy-based product, the method has been validated for high-throughput screening of isoflavones in clinical studies.  相似文献   
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