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The shield tunnels closely constructed near the foundations have an inevitable influence on the structures, even results in the large settlement or uplift of the structures.

The comparison of structural deformation of three different foundations is presented based on the field monitoring data.

Shield tunnelling parameters vary for the different types of foundations. For the long pile foundations, the recommended speed is 3 to 4 cm/min, the grouting pressure is about 0.3 MPa and the grouting rate ranges from 150 to 180.

The study based on the field monitoring data is rarely reported, especially the topic about the structural deformation of different types of the foundations.

This paper aims to analyse the effect of soft soil grouting on the deformation of the closed shield tunnel with the measured data.

Combining the measured data of vertical, horizontal and convergence deformation of the adjacent tunnel during the grouting construction in foundation pit engineering, the influence of grouting on metro tunnel in soft soil area is analyzed.

The researches indicate that early grouting has the main effect on the horizontal displacement of the tunnel; Due to the disturbing effect of the uninterrupted grouting construction on the soil and the transfer pressure of the rheological soil to the bottom of the tunnel, the tunnel is obviously lifted; And the convergence deformation of the tunnel increases caused by the overburden pressure in the vertical direction, so that the tunnel appears the phenomenon of staggered seam, large opening of bolted joint, damaged segment even leakage of water.

The study based on the field monitoring data is rarely reported, especially the topic about inadvertent grouting in soft soil area is likely to cause severe deformation of adjacent metro tunnel.

The forest products processing industry is a key component of the forestry economy, and the level of companies’ operating efficiency directly affects its profitability and market competitiveness.

In order to deeply study the operation status of forest product processing industry, this paper takes the panel data of 70 listed forest product processing companies from 2015 to 2022 as the basis, and adopts BBC, CCR and DEA-Malmquist models to measure the operating efficiency of these companies. Meanwhile, the Tobit model is applied to deeply explore the impact of innovation input on operating efficiency.

The results of the paper show that: (1) the overall operating efficiency of listed forest product processing companies performs well, and the improvement of technology level promotes the growth of total factor productivity; (2) innovation input plays a significant positive role in listed forest product processing companies, which positively affects the operating efficiency.

A scientific and reasonable evaluation of the operating efficiency of listed forest product companies is of great practical significance to the development of the forestry industry The study of forest product processing industry is of key significance to the social economy.

This paper explores the improvement of production and operation efficiency of forest products processing enterprises for the purpose of in-depth analysis of the current situation of China's forest products processing enterprises, which is conducive to improving the innovation and operation efficiency of China's forest products processing enterprises, and realizing the high-quality development of China's forest products processing industry.

Product variant design can only be achieved after all its constituent parts have been implemented by variant design. It is necessary to plan the sequence of part variant design reasonably. The product variant design process involves a large amount of information transfer events at the dimensional level. A reasonable product variant design process needs to make full use of the information transfer characters of parts to decrease the uncertainty of product variant design process. The existing methods of researching the product variant design process mainly focus on resource constraint and activity logic. They are deficient, however, in information transfer resolution and uncertainty management. This paper aims to address these issues.

This paper identifies the number of dimension transfer paths and the position of dimension locating within a transfer path as being the key factors affecting the information transfer role of dimension. Information transfer utility is proposed to measure the information transfer capability of dimensions and parts. Based on these, a two-stage approach of generating the sequence of part variant design based on information transfer utility is proposed.

The uncertainty of dimension constraint network is minimal during the product variant design process when parts are implemented by variant design under the sequence generated through a two-stage method based on the information transfer utilities of parts, as does the times of parameter transferring and iteration in dimension constraint network.

Part variant design under the sequence of descending information transferring utilities can decrease the difficulty of implementing product variant design validly and also increase the efficiency. This suggests an innovative method to planning the product variant design process reasonably from the perspective of informatics.

The aim of this paper is to examine how the co‐evolution of two order systems‐guanxi networks and legal system, i.e. a dual order system‐has shaped the growth of China's SMEs. From an institutional perspective, one proposition suggested has been that building guanxi networks can facilitate the growth of China's SMEs when institutions change in unpredictable ways. Another proposition claims legal institutions become guarantors of the growth of China's SMEs as a result of competition in increasingly market‐oriented environment.

Over a nine‐year period (1998‐2006), this study conducts in‐depth interviews with 18 top managers of three Chinese SMEs in Wenzhou, a city located in south of China. To identify potential research subjects, SMEs that had been operating for a period of at least five years and privately‐owned were chosen. Since institution evolution is characterized with a longitudinal nature, the authors gathered data from three different time periods in order to capture the richness of the phenomenon.

Dual order mechanisms consisting of guanxi networks (informal institutions) and codified laws (formal institutions) are both relevant in the growth of SMEs: guanxi networks are more significant at earlier stages of growth whereas legal systems are more influential in later stages. This argument is supported with data collected from three longitudinal case studies of SMEs in China.

Data were obtained from three companies in Wenzhou of China, thus findings might not be generalizable across the country.

Three longitudinal case studies are unique. According to Pettigrew, longitudinal methods may be the only way to uncover processes of institutional change. The paper investigates the role of dual order system consisting of guanxi and legal systems in the growth of China's SMEs. The research not only contributes to the guanxi literature but also enables managers and investors to better understand the guanxi practice and role of legal systems in the growth of SMEs.

The purpose of this study is to explore the mechanism of branch pits and tunnels formation and increase the specific surface area and capacitance of anode Al foil for high voltage electrolytic capacitor by D.C. etching in acidic solution and neutral.

Al foil was first D.C. etched in HCl-H₂SO₄ mixed acidic solution to form main tunnels perpendicular to the Al surface, and then D.C. etched in neutral NaCl solution including 0.5 per cent C₆H₈O₇ and Cu(NO₃)₂ with different concentration to form branch tunnels normal to Al surface. Between two etching, Cu nuclei were electroless deposited on the interior surface of main tunnels by natural occluded corrosion cell effect to form micro Cu-Al galvanic local cells. The effects of electroless deposited Cu nuclei on cross-section etching morphologies and electrochemical behavior of Al foil was investigated with SEM, polarization curve and electrochemical impedance spectroscopy (EIS).

The results show that sub branch tunnels can form along the main tunnels owing to the formation of Cu-Al micro-batteries, in which Cu is cathode and Al is anode. With increase in Cu(NO₃)₂ concentration, more Cu nuclei can be electroless deposited and serve as the favorable sites for branch tunnel initiation along the whole length of main tunnels, leading to enhancement in specific capacitance of anode Al foil.

Cu nuclei were electroless deposited on the interior surface of main tunnels by natural occluded corrosion cell effect to form micro Cu-Al galvanic local cells, which can serve as the favorable sites for branch tunnel initiation along the main tunnels to enhance specific capacitance of anode Al foil.

Product variant design process consists of a series of asynchronous activities. These activities and the logic relations among them are important in constructing general logic workflow structure, which is the foundation of deriving an activity path for variant design business. Traditional process modeling approaches have not defined activities for product variant design and cannot describe the complex relations among these activities because of the lack of logic express elements. Thus, logic workflow structure modeling method is anticipated to meet the requirements of logic description and path generation in product variant design application. This paper aims to address these issues.

The paper identifies the variant design modes of different types of parts and defines their variant design activities. The procedure of constructing general logic workflow structure of product variant design is proposed. Simultaneously, the principles of inferring logic relations among activities are put forward based on their adjacency information and connectivity probability. A general logic workflow structure of product variant design is constructed. Based on this, activity path corresponding to a variant design business can be generated. The algorithm of generating activity path is designed as well. In addition, Boolean vectors of activity path, based on the functional contour matrix of polychromatic set theory, can be inferred, which denotes the functional character of activity path.

A general logic workflow structure for product variant design has been established, which comprises variant design activities and basic process logic nodes. The logic relations among activities can be inferred based on their in-degree/out-degree and connectivity probability. The function character of activity path can also be expressed based on the polychromatic set theory.

The combination of variant design activity and basic process logic node makes diverse variant design business descriptions possible in a general workflow structure. The proposed approach provides evidences for designer to plan and develop product variant design system effectively.