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Noting that damage occurrence of offshore jacket platforms is concentrated in two structural regions that are in the vicinity of still water surface and close to the seabed, a damage detection method by using only partial measurement of vibration in a suspect region was presented in this paper, which can not only locate damaged members but also evaluate damage severities. Then employing an experiment platform model under white-noise ground excitation by shaking table and using modal parameters of the first three modes identified by a scalar-type ARMA method on undamaged and damaged structures, the feasibility of the damage detection method was discussed. Modal parameters from eigenvalue analysis on the structural FEM model were also used to help the discussions. It is demonstrated that the damage detection algorithm is feasible on damage location and severity evaluation for broken slanted braces and it is robust against the errors of baseline FEM model to real structure when the principal errors is formed by difference of modal frequencies. It is also found that Z-value changes of modal shapes also play a role in the precise detection of damage.

Seven new C14-polyacetylene glucosides codonopilodiynosides A–G (1–7) were isolated from an aqueous extract of the Codonopsis pilosula roots. Their structures were determined by spectroscopic and chemical methods as (–)-(5S,6E,12E)-tetradeca-6,12-dien-8,10-diyn-1,5,14-triol 5-O-β-d-glucopyranoside (1), (–)-(5S,6E,12E)-tetradeca-6,12-dien-8,10-diyn-1,5,14-triol 5-O-β-d-glucopyranosyl-(1″ → 2′)-β-d-glucopyranoside (2), (–)-(5S,6E,12E)-tetradeca-6,12-dien-8,10-diyn-1,5,14-triol 5,14-di-O-β-d-glucopyranoside (3), (–)-(5S,6E)-tetradeca-6-en-8,10-diyn-1,5,14-triol 5-O-β-d-glucopyranoside (4), (–)-(5S,6E,12E)-tetradeca-6,12-dien-8,10-diyn-1,5-diol 5-O-β-d-glucopyranosyl-(1″ → 2′)-β-d-glucopyranoside (5), (–)-(6S,4E,12E)-tetradeca-4,12-dien-8,10-diyn-1,6-diol 6-O-β-d-glucopyranosyl-(1″ → 2′)-β-d-glucopyranoside (6), and (–)-(5S,6E)-tetradeca-6-en-1,5-epoxy-8,10-diyn-14-ol 14-O-β-d-glucopyranosyl-(1″ → 2′)-β-d-glucopyranoside (7), respectively. The absolute configurations of 1–7 were assigned by enzymatic hydrolysis followed by isolation of glucose and aglycones (1a and 4a–7a), and subsequent comparison of specific rotation, TLC, and 1H NMR data of the glucose with an authentic sugar sample and application of modified Mosher's method based on the MPA determination rule of ΔδRS values for 1a and 4a, and ΔδS values for 6a. The configuration of 7 was assigned by electronic circular dichroism calculations based on the quantum-mechanical time-dependent density functional theory.

This paper presents a new algorithm to predict locations and severities of damage in structures by changing modal parameters. An existing algorithm of damage detection is reviewed and the new algorithm is formulated to improve the accuracy of damage locating and severity estimation by eliminating the erratic assumptions and limits in the existing algorithm. The damage prediction accuracy is numerically assessed for each algorithm when applied to a two-dimensional frame structure for which pre-damage and post-damage modal parameters are available for only a few modes of vibration. The analysis results illustrate the improved accuracy of the new algorithm when compared to the existing algorithm.

Currently domestic researches on urban imago space concentrate in a few cities that lie in the advanced region, such as Beijing, Guangzhou, Wuhan, etc., but in so far as those cities that lie in the northwest inland region, the research of this aspect is still few. In order to supplement a special example to the urban imago space theory and to validate former theory, this article studied the Lanzhou urban imago space. During the course of researching, authors adopted some investigating methods, such as visiting on the spot, photograph identification method and sketch map identification method etc. Using investigated data, this paper made an elementary research on urban imago space of Lanzhou, which is a typical valley city in the western China. The result of study indicated that the urban imago space of Lanzhou takes Xiguan Cross as its center (Lanzhou involves four districts of Chengguan, Qilihe, Anning and Xigu). In the process of recognition of urban imago space, the Huanghe (Yellow) River and mountains beside the city are the dominant factors and the main nodes of cognition. So the urban imago space of Lanzhou is quite different from that of plain cities. Interviewee did well in the spatial structure map, which was made up of mountainous land, river and main trunk roads, the group structure took profound impression on people.

Based on the definition of the concept of city growth, the paper mainly discussed the factors which impact the growth of Chinese cities in the transitional period by selecting the proportion of city construction land area to the area of the city X1（%）, green coverage ratio of the built up area X2（%）, the ratio of personnel involved in the secondary industryX3（%）, the GDP per capita X4（×104）and other 43 indicators, by relying on the relevant data from China Urban Statistical Yearbook（2008）, by applying SPSS statistical software and by applying the Factor Analysis and Regression Analysis. The results show that the factors which affect the city growth have four major groups, namely economic and institutional factors, location factors, environmental factors and social cultural services and functions. Among the factors which affect Chinese city growth, the general budgetary expenditures and the general budgetary revenues of local public finance are the most important factors. The general budgetary expenditures of local finance, the general budgetary revenues, the lands of urban construction and other 12 factors obtained by gradually excluding method can be used to present the coefficient of city growth.

Well located at the geometric center of China, Lanzhou is one of the typical valley-basin cities in the western China. There are mountains alongside and Yellow River wandering through the city. Here we choose Lanzhou built-up area as research object, which ranges from 36deg 00' N to 36deg 10' N and 103deg 31' E to 104deg 00' E. The study area includes four districts (Chengguan, Qilihe, Anning, and Xigu) of Lanzhou city with total area and population is 227.98 km2 and 1,800,000 respectively. Under the planned economic system, housing is welfare system inside the units, so the residents barely have choices for houses. Therefore, urban residential spatial differentiations mainly lie on units' ownership, location, economic efficiency, scale, housing system etc. With the establishment of market economic system, the previous welfare system residential model was partly impacted by the durative differentiation and conformity of the urban residential district spatial structure in Lanzhou. The valley-basin shaped city is a kind of special city; we take the Lanzhou city as a case to investigate the urban residential district differentiations, spatial evolvement and mechanism. Furthermore, the article suggests the trend and direction of the urban residential spatial differentiations in Lanzhou in the future.

The fast Fourier transform (FFT) and digital filter design are two basic parts of digital signal processing (DSP). Combining FFT and filter design, this paper proposes a mode shape testing method based on data acquisition, analysis and processing. In addition to these, the paper takes a simple-supported beam as an example to validate the method and achieves a satisfactory result.