Previous studies identified large differences between countries in the extent to which childbearing intentions are realised. Failure to realise an intention to become a parent was found to be particularly common in the post-socialist countries. In this paper we examine whether similarly low rates of realisation of fertility intentions can be found in Poland. We use two waves of the Polish Generations and Gender Survey (GGS-PL), conducted in 2010/2011 and 2014/2015. We first describe fertility intentions of Polish women and men as declared at the survey’s first wave. Next, we examine whether the short-term childbearing intentions expressed at wave 1 were followed by an actual birth by the second round of the data collection. For the respondents who did not get a child between waves 1 and 2, we analyse the stability of their fertility plans. We find that approximately 35% of the respondents who at wave 1 intended to have a child in the next three years actually had one by wave 2. Both realisation and stability of fertility intentions varied markedly by gender and parity.
There is a growing interest in new transportation routes that combine benefits of shorter distances, cost-effective transits and routes not troubled by maritime security concerns. The Northwest Passage offers a package of routes through the Canadian maritime zone; it is 9,000 km shorter than the Panama Canal route and 17,000 km shorter than the Cape Horn route. The Northern Sea Route shortens a Hamburg-Yokohama voyage by 4,800 miles, in comparison with the Suez Canal route. The transpolar route, if it materializes with an ice-free Central Arctic Ocean route, would shorten distances even further. Given the increase in regional and international navigation and shipping in the region, it is therefore not surprising that in recent years Arctic States and international bodies focused on the needs of enhanced safety and environmental standards for polar shipping. In addition to the dedicated domestic polar shipping regulation, primarily in Canada and the Russian Federation, the Arctic Council and International Maritime Organization (IMO) have launched important initiatives. The most important is establishing of international rules for ships operating in polar waters – The Polar Code.
Deriving the formulas for strain components, we are assuming, that cross-section of a rod being rotated in space during deformation does not need to be perpendicular to deformed centroid line. This not a quite intuitive assumption allows for more compact and easier formulas for strain tensor or equilibrium equations. Derived transformations between actual and initial coordinate system, components of strain tensor and virtual works principle for investigated spatially curved beams of bisymmetric cross-section are shown in this paper. Conformity with other models from referenced literature is also shown.
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