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PurposeThe aim of this paper is to examine the effect of organizational environment on engineering project cost management.Design/methodology/approachTaking China Railway Engineering Corporation 2nd Bureau (CREC 2nd Bureau for short) as an example, the authors conduct lots of semi‐structured interviews in its group corporation, company limited, two subsidiaries and two project departments, and finally collect textual data which include 30 paragraphs and more than 120,000 words. The authors then encode those interview data step by step for further analysis under the research paradigm of grounded theory.FindingsBased on these encoded data, the paper builds concept, basic categories, main categories, which could be the factors affecting the engineering project cost management, the evidence chain and the complete story clue among these categories. Then finally constructs a theoretical framework called “3S” for short, which is comprised of the organizational structure supporting system, the control procedure supporting system and the social relation supporting system.Research limitations/implicationsBecause of the insufficient importance placed on engineering project cost management by academics and few theoretical papers, this paper provides a new method for exploring the engineering project cost management and a theoretical reference for further research.Practical implicationsIn this paper, the authors discuss the action mechanism of organizational environment in the engineering project cost management and provide for Chinese construction enterprises more explicit guidance on their cost management practice.Originality/valueThere is little research on determinants of engineering project cost by Chinese scholars, which is mainly shown as normative research. There is no perfect theoretical framework on the determinants of engineering project cost management, which is not beneficial to the knowledge of engineering project cost management and is not comprehensive and in depth enough for academics and practitioners. This paper conducts a field study in CREC 2nd Bureau based on grounded theory. At last, “3S” theoretical framework is established. This paper is embodied in using reality as the accordance, scientifically carding and spreading the theory and translating the practical experience into theory, so that it is beneficial for the engineering project cost management.

In order to further improve the teaching effect of college classrooms, this paper analyzes the main performance of college teachers' classroom teaching leadership under the background of multimedia technology. Using the quadrant model to analyze the performance of classroom teaching leadership in colleges and universities, the final conclusion is that classroom teaching leadership in colleges and universities under the background of multimedia technology is actually a kind of teacher personality influence. This influence is mainly reflected in the love for students, but also includes normative requirements from the teaching profession. This provides a feasible idea for effective classroom teaching in colleges and universities under the background of multimedia technology.

It is inevitable that renewable energy consumption will increase as installed capacity continues to increase, primarily wind and photovoltaic power generation. Power to Gas (P2G) technology can store electrical energy in the form of chemical energy on a large scale. Reversible solid oxide cell (RSOC) has a very high conversion efficiency in both electrolytic gas production and fuel cell power generation compared with traditional electricity-to-gas devices. For the future integrated energy system, Reversible solid oxide cells are expected to play a significant role in integrating power generation and energy storage. This work proposes a new integrated energy system based on Reversible solid oxide cell for photovoltaic (PV) consumption. The Integrated Electricity-Gas System (IEGS) considers the two modes of electrolysis and power generation of Reversible solid oxide cell in the model. The model takes the minimum running cost as the objective function to linearize part of the model to generate a mixed integer linearization problem and solve it in GAMS. The case study shows that wind power is maximized, and the gas mixture can be transported in natural gas pipelines, improving the economics and stability of Integrated Electricity-Gas System. This work not only can reduce the operating cost of the system but also increase the high penetration of photovoltaic power generation. A quantitative assessment of the impact of hydrogen injection ratio and renewable energy penetration was also carried out.

The connection of subway stations to surrounding underground spaces inevitably involves opening construction in the existing underground structure. The opening construction can strongly impact the existing underground structure when there is no reserved condition. In this study, three-dimensional numerical simulation, model test, and theoretical analysis are used to analyze the mechanical behaviors of side wall opening construction in a mined excavation subway station-Xuanwumen Station of Beijing Subway Line 4. Based on the deformation and stress characteristics of the existing side wall structure, two different reinforcement measures are compared. It is found that the vertical and horizontal deformations of the existing structure caused by opening construction is −1.58 and −1.79 mm, respectively, which are lower than the subway deformation control requirements (3 mm). However, the first and third principal stress increments are 2.14 and −4.62 MPa, respectively, which are markedly higher than the control requirement (10%). A “two-step opening” method is proposed for side wall opening construction in underground structures based on the solution of complex function to the orifice problem. This theoretical method is validated by numerical simulations and model tests, achieving highly consistent results. The allowable ultimate span of side wall opening is 5.75 m without reinforcement. Findings of the present study provide a reference for the design and construction of side wall openings in similar underground spaces.