Vulnerability Analysis against Natural and Technological Threats: A Comparative Assessment in Tehran Metropolis Gas Supply Network

Resilience as a counterpoint to vulnerability can reduce the vulnerability of various natural, man-made, and technological threats in complex technical systems. The present study was designed and conducted with the aim of comparative assessment of the vulnerability of a gas supply network to natural and technological threats. This descriptive-analytical and cross-sectional study was carried out in Tehran metropolis gas supply network including town board stations, gas supply, and distribution networks in 2019-2020. The study was based on the vulnerability analysis method including three factors of likelihood, severity of consequences, and the degree of preparedness for threats. Comparative vulnerability assessment in these three sections of the gas supply network was performed using IBM SPSS software v. 23.0. Out of eleven identified hazardous elements, the vulnerability index for three hazardous elements was estimated as a weak level threat; four hazardous elements as a medium level threat and the vulnerability index for four hazards were evaluated as a severe threat. The results of comparative vulnerability assessment based on three parts of gas supply network showed that the highest vulnerabilities related to the gas distribution network (133.66±24.63), gas supply network (115.0±35.35), and town board stations (79.49±68.51. In addition, the results of Kruskal-Wallis test showed that the vulnerability difference in these three sections was not significant (p>0.05). The findings of the comparative assessment of vulnerability between different parts of the gas supply network including town board stations (TBS), gas supply and distribution network indicated that the resilience of these parts is relatively low and requires special attention in order to reduce vulnerability in Tehran metropolis gas supply network.

An Accurate Leakage Localization Method for Water Supply Network Based on Deep Learning Network

In the water supply network, leakage of pipes will cause water loss and increase the risk of environmental pollution. For water supply systems, identifying the leak point can improve the efficiency of pipeline leak repair. Most existing leak location methods can only locate the leak point approximately to the node or pipe section of the pipe network, but cannot locate the specific location of the pipe section. This paper presents a framework for accurate location of water supply network leakage based on ResNet. The framework is to pinpoint leaks to specific locations along the pipeline. The leakage of two kinds of pipe networks is simulated. For a pipe network containing 40 pipes, the positioning accuracy of the pipe section is 0.94, and the MSE of the specific location of the leakage point is 0.000435. For the pipe network containing 117 pipes, the positioning accuracy of the pipe section is 0.91, and the MSE of the specific location of the leakage point is 0.0009177, and the leak location ability under different sensor arrangements is analyzed. Experiments verify the robustness and applicability of the framework.

Linking supply network flexibility with mass customization capability

Purpose The importance of supply network flexibility (SNF) in the development of mass customization capability (MCC) has been implied in the literature but seldom subjected to empirical investigation. To fill the gap and contribute to MC literature, this paper aims to examine the role of SNF in facilitating the development of MCC of organizations. Furthermore, it has been investigated whether the use of information and communication technologies (ICTs) strengthens the above relationship. Design/methodology/approach Drawing on the supply chain literature and dynamic capability theory, the study proposes a research framework depicting the interconnectedness among the variables of interest. The proposed framework has been tested using structural equation modelling based on partial least squares by using the data collected from a questionnaire-based survey of a sample of Indian manufacturing organizations. Findings The findings indicate that the dimensions of SNF, namely, sourcing flexibility and supplier flexibility, positively affect the MCC of the organizations and the strength of these relationships is further amplified by the implementation of ICTs. Practical implications The study shows the managerial opportunities for the development of a flexible and competent supply network to facilitate the development or enhancement of MCC. Originality/value This study contributes to scant literature by providing empirical evidence for the relationship between SNF and MCC. Further, this study enriches the understanding of the crucial role of ICT by exploring its moderating effect on the relationship between the variables of interest.

Product Flexibility Strategy Under Supply and Demand Risk

Problem definition: With heightened global uncertainty, supply chain managers are under increasing pressure to craft strategies that accommodate both supply and demand risks. Although product flexibility is a well-understood strategy to accommodate risk, there is no clear guidance on the optimal flexibility configuration of a supply network that comprises both unreliable primary suppliers and reliable backup suppliers. Academic/practical relevance: Existing literature examines the value of flexibility with primary and backup suppliers independently. For a risk-neutral firm, research shows that (a) incorporating flexibility in a primary supplier by replacing two dedicated ones (in absence of backup supply) is always beneficial and that (b) adding flexibility to a reliable backup supplier (in absence of product flexibility in primary suppliers) is always valuable. It is unclear, however, how flexibility should be incorporated into a supply network with both unreliable primary suppliers and reliable backup suppliers. This research studies whether flexibility should be incorporated in a primary supplier, a backup supplier, or both. Methodology: We develop a normative model to analyze when flexibility benefits and when it hurts. Results: Compared with a base case of no flexibility, we prove that incorporating flexibility in either primary or backup suppliers is always beneficial. However, incorporating flexibility in both primary and backup suppliers can be counterproductive because the supply chain performance can decline with saturated flexibility, even if flexibility is costless. A key reason is that the risk-aggregation effect of consolidating flexibility in an unreliable supplier becomes more salient when flexibility is already embedded in a backup supplier. Managerial implications: This research refines the existing understanding of flexibility by illustrating that flexibility is not always beneficial. When there is a choice, a firm should prioritize incorporating flexibility in a reliable backup supplier.

Developing a resilient, robust and efficient supply network in Africa

PurposeSupply chains need to balance competing objectives; in addition to efficiency, supply chains need to be resilient to adversarial and environmental interference and robust to uncertainties in long-term demand. Significant research has been conducted designing efficient supply chains and recent research has focused on resilient supply chain design. However, the integration of resilient and robust supply chain design is less well studied. The purpose of the paper is to include resilience and robustness into supply chain design.Design/methodology/approachThe paper develops a method to include resilience and robustness into supply chain design. Using the region of West Africa, which is plagued with persisting logistical issues, the authors develop a regional risk assessment framework and then apply categorical risk to the countries of West Africa using publicly available data. A scenario reduction technique is used to focus on the highest risk scenarios for the model to be tractable. Next, the authors develop a mathematical model leveraging this framework to design a resilient supply network that minimizes cost while ensuring the network functions following a disruption. Finally, the authors examine the network's robustness to demand uncertainty via several plausible emergency scenarios.FindingsThe authors provide optimal sets of transshipment hubs with varying counts from 5 through 15 hubs. The authors determine there is no feasible solution that uses only five transshipment hubs. The authors' findings reinforce those seven transshipment hubs – the solution currently employed in West Africa – is the cheapest architecture to achieve resilience and robustness. Additionally, for each set of feasibility transshipment hubs, the authors provide connections between hubs and demand spokes.Originality/valueWhile, at the time of this research, three other manuscripts incorporated both resilience and robustness of the authors' research unique solved the problem as a network flow instead of as a set covering problem. Additionally, the authors establish a novel risk framework to guide the required amount of redundancy, and finally the out research proposes a scenario reduction heuristic to allow tractable exploration of 512 possible demand scenarios.

International Procurement and Supply Network Management in the Post COVID 19 Era in Nigeria: A Literature Review

Introduction: The global economy has been greatly affected by the outbreak of the COVID-19 pandemic and its impact on the oil and gas industry is also being felt immensely as the industry relies heavily on the importation of the goods and services that they require to run their operations effectively and efficiently and the only way to get to the final destination of these company is through a well-managed supply network. Purpose: The purpose of this study was to examine international procurement and supply network management in the post COVID 19 Era in Nigeria. Being a literature review, the paper adopted a desk research methodology. Findings: The findings of the review of literature reveal that international procurement significantly influence and predicts supply network management performance. It also shows that COVID-19 has negatively affected both international procurement and supply network management, and that the phrase supply network management, instead of supply chain management, is most appropriate to describe the activities and relationships between and amongst individuals, enterprises, facilities and information, materials and services systems that connects supplier’s suppliers to customer’s customers capturing the multiple and complex relationships that exists amongst them.