The behaviour of saturated, porous media under dynamic or quasi-static loads was first formulated by Biot (1941, 1960). For dynamic problems a simplification was recently proposed by one of the Authors. As the two formulations must coincide over a range of problems and as for slow transients both must be adequately represented by pure consolidation theory, this Paper examines the respective ranges of validity by an analytical study of a soil layer subject to a periodic surface force. The analysis also indicates under what conditions such extremes as undrained or quasi-static assumptions can be safely used. Results of the analysis are given in a non-dimensional, generally valid, form and should find practical application in assessing the the type of approximation that is applicable in new problems. Le comportement des milieux poreux saturés soumis à des charges dynamiques ou quasi statiques a été analysé pour la première fois par Boit (1941, 1960). Pour les problèmes dynamiques, une simplification a été récemment proposée par l'un des Auteurs. Comme les deux formulations doivent coincider pour une certaine gamme de problèmes et que, dans le cas de phénomènes transitoires lents, elles doivent toutes deux être représentées d'une manière correct par une théorie de consolidation pure, cet Article examine les zones respectives de validité en étudiant analytiquement une couche de sol soumise à une force supercielle péiodique. L'analyse indique également dans quelles conditions les hypothèses extrêmes de charges non drainées ou quasi statiques, peuvent être utilisés sans risque d'erreur. Les résultats de l'analyse sont donnés sous une forme non dimensionnelle, généralement valable, et devraient trouver leur application pratique dans l'évaluation du type d'approximation applicable à de nouveaux problèmes.

A novel approach to modulate the nucleation and growth of perovskite crystals by intermixing precursor-capped nanoparticles has been reported.

Purpose - The purpose of this paper is to explore and analyse the risks in container shipping operations from a logistics perspective. In the paper, risks associated with the three flows in logistics − information, physical, and payment flow are identified and analysed. Design/methodology/approach - The use of case study method was first explained and justified. Second, risk identification was started with supporting references, several interviews were then conducted to identify and validate the potential risks in container shipping operations. A questionnaire was deployed to collect related data; and the impacts of the risks were then assessed and ranked using the method of risk mapping. Findings - The paper has identified a total of 35 risk factors and classified them into different categories. The paper has also revealed that the risks associated with physical flows have more serious risk impacts than the other types of risks; however, one of the risk factors associated with information flow (shippers hiding cargo information) is the most significant one among all the factors. Originality/value - Although many studies have been conducted on container shipping operational risks, no studies so far have approached this issue from a perspective that inclusively examines all the possible risks and comprehensively evaluates the relative importance of each of them. This study has identified the risks in container shipping operations, and analysed and ranked the level of these risks. The research further “refines” the findings of some previous studies by placing the risk factors addressed therein in a full “risk picture” which was developed systematically

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