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A natural gas pipeline accident could prove to be a dangerous fire source in city centers. Taking the explosive danger caused by natural gas leakage as an example, the purpose of this paper, based on the box model, is to examine how such an environmental hazard can be hindered by the variation of building heights in the context of urban safety design and land‐use decision making.

The box model measures the concentration of pollutants within a defined box in which a mixture of pollutants with air and their transport by wind take place. A street surrounded by tall buildings in the city center is a good example for the application of such a model, and the building heights shape the box size and the mixing height. Under the consideration of atmospheric conditions this study identifies how the constellation of physical factors shaping the city‐street box and its change affect the elapsed time to reach the lower explosive limit (LEL) and the upper explosive limit (UEL) of natural gas.

Ceteris paribus higher building heights expand the time span between initial gas leakage and reaching LEL, in which appropriate safety measures should be taken before ignition, but more rapidly increases the elapsed time to reach UEL, making the time scope for potential explosive danger in the city center even larger.

In the past, the aspect of preventing explosive dangers caused by natural gas leakage has been largely ignored in the building height regulations related to urban safety design and city center development.

This paper aims to investigate the reason for natural gas leakage from transmission pipelines between Linyi and Shouguang in China during sealing tests, explore the failure mechanism and provide a reference for taking reasonable measures to prevent such accidents.

Failure analysis for the steel pipe has been addressed with different methods, such as microstructure analysis, inclusion analysis, corrosion product analysis, macro- and micro-morphology analyses and bacterially catalyzed experiments.

Several bulges were observed, especially at the bottom of the steel pipe sample, with the distribution and positioning not related to the weld. The inner surface of the steel pipe was severely corroded, and the oxide scale was flaking in many places. The greatest corrosion area was identified at the bottom of the steel pipe near the gas leakage point. Severe pitting and perforation corrosion in the pipeline were observed, and the main corrosion reaction products were Fe3O4, FeO and FeS. The grain orientation distribution near the crack (coarse grains <101> and fine grains <111> at the microcrack tip) indicates that fine grains may be beneficial in hindering crack propagation.

The principal mechanism for the corrosion failure is supposed to be due to the interaction of chloride ions with the sulfate-reducing microorganisms present and the stress corrosion cracking by chloride and sulfide formed by the sulfate-reducing microorganisms.

Research on customer value in business markets is still at an early stage. More specifically, business marketing literature is largely silent on how customers' value expectations interact with suppliers' value propositions and how the interaction leads to development of new products and services. The purpose of this paper is to explore this interaction process and map the journey of the development of a new service and a new relationship.

Following a case study approach, data were collected from representatives of supplier firm – GASCO, and the buyers in CERACO, through in‐depth interviews. In total, 21 ceramic manufacturers (customers) were also visited who represent CERACO. Semi‐structured interviews were conducted with few key representatives of ceramic manufacturers, equipment supplier representatives, and GASCO representatives. Also interviewed were two vendors of GASCO and a representative of the gas pipeline (infrastructure) company close to GASCO. Themes were identified in the analysis of the semi‐structured interview transcripts, focus group discussions and the documented information.

The authors' case study highlights a nine‐step CVE‐SVP interaction process: reduce business discontinuities for customers; latent value co‐creation opportunity for a new supplier; collaborative partnership with high customer involvement; enhancing CVE of the new offering; keeping customer switching costs low; offering alternate customer solutions; reduce potential new business discontinuance for the customers; create value for customers' end customers; and co‐create value for customers in the long term.

The authors' case study, in an emerging market context of India, probably for the first time studies the interplay of regulatory forces, customer value expectations, and supplier‐driven markets in shaping the supplier value propositions. This context of the case study, which is so different from a customer‐driven market, makes this case study unique.

The purpose of this paper is to analyze stability of Jintan underground rock salt gas storage caverns during operation period. Some factors such as complex geological and operation conditions and high variability of physico‐mechanical parameters which will influence the safety of underground storage caverns are also considered.

In this paper, taking account of stability and sealability, numerical models of single cavern and two caverns for Jintan rock salt are established and calculated based on Mohr‐Coulomb criterion and damage‐dilatancy criterion. Response surface method combining with Monte Carlo method are adopted to calculate the failure probabilities of elements near the caverns. Various working conditions including different operation pressures and distances between caverns are also considered.

Shear failure is the main failure mode of Jintan underground rock salt gas storage caverns. The major failure area is located in the middle of the cavern. Reliability of the middle part of the cavern improves as storage pressure increases.

According to the simulation results on stability and sealability of caverns, the smallest internal operation pressure should be controlled strictly during the gas release process. Plastic area and failure probabilities of elements near the caverns increase obviously as the distance between caverns decreases. Damaged and dilatancy areas have the same trend. Twice the diameter of the cavern is recommended as the minimum distance between caverns.

The conclusions can be used as a guide during operation and design period of underground caverns.

The research activity presented in this paper has the objective of developing models for the evaluation of technological risk and loss of production due to failures, which are among the criterions that enable the choice of optimal scenarios for energy supply. This activity is based on the European Project “Risk of Energy Availability: Common Corridors for Europe Supply Security” (REACCESS), which aims to develop an analytical tool to analyse scenarios for future secure European Union (EU) energy supply.

The paper proposes an innovative approach, since nowadays a generalised analytic model for risk assessment in large‐scale energetic systems does not exist. In particular, the methodology adopted includes models to assess risk for people safety, risk for the environment and availability for corridors and the related infrastructures. As regards technological risk, accidents producing loss of lives in the population and environmental damage are taken into account; while for the loss of production primary attention is paid to technical failures and maintenance.

Since the analytic models developed perform a large‐scale assessment, they must be flexible and simplified to adapt to different situations and to be easily updated when different future scenarios are investigated. Details of the analysis depend on the precision of data collected and inserted in the models. The damage assessment is affected by deficiency and uncertainties related to territorial and statistical data. Nevertheless, the outcomes obtained for each energy commodity are reasonable and often comparable to literature data.

Based on this study output, technological risk can be considered, more systematically than in the past, in the selection of EU strategies for future energy supply. The corridors social cost is included in future strategies selection, in addition to purely economical and environmental evaluations.

This analysis develops and predicts a politically controversial idea, namely that nuclear fission power will be the dominant energy resource of the 21st century. Abundant energy enables higher and more efficient utilization of resources. Energy drives the engines of industrial and food production, transportation, building construction, space heating, transformation of landscapes, recreation, etc. This article compares other energy alternatives with the potential of nuclear fission power. It predicts that several hundred nuclear plants, each nominally of 10 gigawatts capacity, could supply the world’s energy requirements without creation of polluting greenhouse gases. Moreover, the superabundance of power this would represent could feed the world, supply its drinking water, and raise the per capita income and standard of living to levels where total human population would level off at an acceptable number. However, realization of such benefits requires unprecedented world cooperation, and these issues are also treated in this article.