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The simulated temperature profile of the printed circuit board assembly (PCBA) during reflow soldering process deviates from the actual profile. To reduce this relative deviation, a new strategy based on the Kriging response surface and the Multi-Objective Genetic Algorithm (MOGA) optimizing method is proposed.

The simulated temperature profile of the PCBA during reflow soldering process deviates from the actual profile. To reduce this relative deviation, a new strategy based on the Kriging response surface and the MOGA optimizing method is proposed.

Several critical influencing parameters such as temperature and the convective heat transfer coefficient of the specific temperature zones are selected as the correction parameters. The hyper Latins sampling method is implemented to distribute the design points, and the Kriging response surface model of the soldering process is constructed. The updated model is achieved and validated by the test. The relative derivation is reduced from the initial value of 43.4%–11.8% in terms of the time above the liquidus line.

A new strategy based on the Kriging response surface and the MOGA optimizing method is proposed.

This paper aims to the perspective of stakeholders, from external variables of the Building Information Modeling (BIM) system, users, task flow, the nature of the development of the execution process, organizational structure and policy impacts, that established a relationship among the internal concepts and intentions for the BIM application, individual or organizational differences, controlling interference factors and environmental constraints, discussed the combination of the values and barriers of BIM implementation.

Through the co-occurrence statistics and genre analysis based on co-citation context analysis and constructs the common information that impacts the combination of values and barriers of BIM implementation. Then, the paper chose the expert database of the green construction and intelligent building branch of the China construction association, and obtained 104 sample data through modified snowball sampling, using exploratory factor analysis with factor load linear functions, combined factor variance contribution rate weights.actor variance contribution rate weights.

The results show that eight aspects can be defined as the values of BIM implementation (VI), and the barriers of BIM implementation (BI) mainly come from five aspects caused by insufficient cognition and two aspects of an uncertain value in China.

This research reflects a combined evaluation of the values of BIM implementation and barriers of BIM and highlights the significance of the sustainable development of BIM technology and the value of building future informatization applications.

The purpose of this paper is to investigate and explain thermal oxide effect on electrochemical corrosion resistance anodized stainless steel (SS).

Electrochemical corrosion resistance of thermal oxides produced on anodized 304 SS in air at 350°C, 550°C, 750°C and 950°C in 3.5 wt.% NaCl solution have been investigated by dynamic potential polarization, EIS and double-loop dynamic polarization. Anodized 304 SS were obtained by anodization at the constant density of 1.4 mA.cm^-2 in the solution containing 28.0 g.L^-1H₃PO₄, 20.0 g.L-1C₆H₈O₇, 200.0 g.L^-1H₂O₂ at 70°C for 50 min. SEM and EDS had been also used to characterize the thermal oxides and passive oxide.

Interestingly, anodized 304SS with thermal oxide produced at 350°C displayed more electrochemical corrosion and pitting resistance than anodized 304 SS only with passive oxide, as related to the formation of oxide film with higher chromium to iron ratio. Whereas, anodized 304SS with thermal oxide formed at 950°C shows the worse electrochemical corrosion and pitting resistance among those formed at the high temperatures due to thermal oxide with least compact.

When thermally oxidized in the range of 350°C–950°C, electrochemical corrosion and pitting corrosion resistance of anodized 304 SS decrease with the increase of temperature due to less compactness, more defects of thermal oxide.

The purpose of this investigation was to research the corrosion behavior of welded joints of bimetallic composite tube (X65/316L) welded with Inconel 625 in simulated sea water and in simulated production water, respectively.

The different electrochemical corrosion and galvanic corrosion behaviors of different welded zones were identified using the dynamic potential scan method and galvanic corrosion technique.

The heat-affected zone (HAZ) of welded joints was the most critical zone for corrosion. The closer to the welding line, more severe was the corrosion that was evident in the HAZ at room temperature. In welded joints of X65 tested in simulated seawater, tremendous corrosion occurred in the HAZ, followed by the base metal, and finally the welding line. However, there were few differences in corrosion of the different zones of welded joints in 316L in simulated production water. In such joints of 316L, corrosion comparatively attacked more easily to the HAZ. In galvanic corrosion tests, tremendous galvanic corrosion was evident on welded joints on X65, but comparatively slight gavanic corrosion appeared at welded joints in 316L. With the increased temperature, galvanic corrosion of welded joints was enhanced.

The results can provide reference for reducing the gavalic corrosion of welded bimetallic composite tube metal in the actual operation.