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A new H-section steel support system is introduced based on a foundation pit project in Shanghai. In-situ monitoring was carried out to measure the displacement of supporting piles. The monitoring results showed that the displacement of pile-top was closely related to the excavation depth and time. It is basically no longer developing after the foundation slab concreted finished. Horizontal displacement of the pile body increased gradually with the increase of excavation depth. The maximum horizontal displacement was about 25 mm and the position was about 1 m below the bottom of the foundation pit. Finally, the horizontal displacement of the pile body was presented as a "bow" with a small displacement at two ends and a large displacement in the middle. Compared with those at reinforced concrete support area, it showed that the deformation law and final displacement value of pile-top and pile body in the new H-section steel support area was basically the same as that of reinforced concrete support area. And all of the monitoring data were within the security range, meeting the design and code requirements. Moreover, new H-section steel support system construction period was short and the cost was low. It could effectively improve the green construction level. The conclusions obtained in this paper could be referred for other familiar projects.

High-density genetic linkage maps are necessary for precisely mapping quantitative trait loci (QTLs) controlling grain shape and size in wheat. By applying the Infinium iSelect 9K SNP assay, we have constructed a high-density genetic linkage map with 269 F 8 recombinant inbred lines (RILs) developed between a Chinese cornerstone wheat breeding parental line Yanda1817 and a high-yielding line Beinong6. The map contains 2431 SNPs and 128 SSR & EST-SSR markers in a total coverage of 3213.2 cM with an average interval of 1.26 cM per marker. Eighty-eight QTLs for thousand-grain weight (TGW), grain length (GL), grain width (GW) and grain thickness (GT) were detected in nine ecological environments (Beijing, Shijiazhuang and Kaifeng) during five years between 2010-2014 by inclusive composite interval mapping (ICIM) (LOD ≥ 2.5). Among which, 17 QTLs for TGW were mapped on chromosomes 1A, 1B, 2A, 2B, 3A, 3B, 3D, 4A, 4D, 5A, 5B and 6B with phenotypic variations ranging from 2.62% to 12.08%. Four stable QTLs for TGW could be detected in five and seven environments, respectively. Thirty-two QTLs for GL were mapped on chromosomes 1B, 1D, 2A, 2B, 2D, 3B, 3D, 4A, 4B, 4D, 5A, 5B, 6B, 7A and 7B, with phenotypic variations ranging from 2.62% to 44.39%. QGl.cau-2A.2 can be detected in all the environments with the largest phenotypic variations, indicating that it is a major and stable QTL. For GW, 12 QTLs were identified with phenotypic variations range from 3.69% to 12.30%. We found 27 QTLs for GT with phenotypic variations ranged from 2.55% to 36.42%. In particular, QTL QGt.cau-5A.1 with phenotypic variations of 6.82-23.59% was detected in all the nine environments. Moreover, pleiotropic effects were detected for several QTL loci responsible for grain shape and size that could serve as target regions for fine mapping and marker assisted selection in wheat breeding programs.

Pipeline leakage and pipeline internal corrosion are two serious threats to pipeline safety operation. In this study, based on the measurement theory of pipeline internal diameter variation and a numerical simulation analysis of existing sensor shortcomings, a novel FBG pipe-fixture sensor is designed and developed to detect pipeline leakage and monitor pipeline internal corrosion simultaneously. A calibration test is conducted, and the test results indicate that the FBG pipe-fixture sensor solves the problem of a large difference between the test values and the theoretical values and eliminates the limitation of measurement range. To validate the actual performance of the sensor, a pipeline leak detection test and a pipeline internal corrosion monitoring test are, respectively, conducted on a steel pipe leak test platform and a steel pipe with different simulated corrosion levels. The test results demonstrate that the FBG pipe-fixture sensor can effectively detect pipe leakage and decrease the localization error of the leakage point to within 1 m. The sensor can also effectively monitor pipe internal corrosion and evaluate the internal corrosion degree with a measurement accuracy of 0.1 mm. The novel FBG pipe-fixture sensor may be a potential sensor for pipeline leak detection and pipeline internal corrosion monitoring. [ABSTRACT FROM AUTHOR]

In order to solve the problem of fuzzy design constraints and incompleteness of key information in conceptual design stage, a conceptual design method based on product genes was proposed, overcoming some blindness in design process and improving the feasibility of designed schemes. Firstly, a conceptual design process model was established. Based on this, a new definition and composition of product genes was put forward. Then, a product gene coding method based on functional elements was proposed. Finally, a genetics-based conceptual design method was described with an unmanned probe car as an example. The results show that this method can clarify the key information of products in the conceptual design process, and reduce the blindness of design so as to improve the feasibility of design schemes and the design efficiency. [ABSTRACT FROM AUTHOR]