Development of a Field Instrument to Quantify Frictional Drag of an In-Service Ship Hull

2015 ◽  
Author(s):  
J. Travis Hunsucker ◽  
Geoffrey Swain
Keyword(s):  
19Th Century ◽  
Detrimental Effect ◽  
Experimental Testing ◽  
Channel Length ◽  
Full Scale ◽  
Frictional Drag ◽  
Late 19Th Century ◽  
Marine Fouling ◽  
Accurate Quantification

It has been shown that the presence of marine fouling, even as a light slime, will cause a detrimental effect on the powering or speed of a full-scale ship. Studies from as early as the late 19th century have attempted to quantify the increase in power or decrease in speed imposed on a ship from the presence of hull roughness. The accurate quantification is limited and often difficult and expensive to obtain. The present study aims to develop an instrument that will remove some ambiguity by directly measuring the frictional drag of a ship in situ. Results from experimental testing of a prototype in the lab are presented and used to identify the channel length, height, and accuracy limitations of a field deployable prototype.

Is the European red fox a vector of the invasive basket asparagus (Asparagus aethiopicus) in eastern Australia?

2020 ◽  
Vol 42 (2) ◽  
pp. 204
Author(s):  
Julie M. O'Connor ◽  
David M. Burrows ◽  
Benjamin L. Allen ◽  
Scott E. Burnett
Keyword(s):  
Seed Dispersal ◽  
19Th Century ◽  
Vulpes Vulpes ◽  
Invasive Plant ◽  
Red Fox ◽  
Late 19Th Century ◽  
Eastern Australia ◽  
Primary Means ◽  
Avian Seed Dispersal

Basket asparagus (Asparagus aethiopicus) has become a naturalised invasive plant in some coastal areas of Australia since its introduction in the late 19th century. Its spread through garden waste dumping and avian seed dispersal has been well documented and both are considered to be the primary means of dispersal. While a small number of avian vectors have been identified, no Australian studies have investigated the potential of mammals to disperse basket asparagus seeds. We collected basket asparagus seeds from fox (Vulpes vulpes) scats collected in the field, confirmed the viability of these seeds in germination trials, and further documented the germination of basket asparagus seeds from an undisturbed fox scat in situ. These results demonstrate that foxes consume and disperse basket asparagus seeds, and that these seeds are viable and germinate under field conditions. Foxes not only use basket asparagus stands as harbour, but can also facilitate the plant’s dispersal in coastal ecosystems.

Битвазапрошлое:храмсвятогоГеоргия вИзраавэпицентре церковно-политическойборьбыконцаXIXв.

2019 ◽  
pp. 256-281
Author(s):  
E.M. Kopot`
Keyword(s):  
Middle East ◽  
Ottoman Empire ◽  
19Th Century ◽  
Russian Empire ◽  
Foreign Affairs ◽  
Late 19Th Century ◽  
History Of ◽  
The Russian Empire ◽  
First Time ◽  
The Church

The article brings up an obscure episode in the rivalry of the Orthodox and Melkite communities in Syria in the late 19th century. In order to strengthen their superiority over the Orthodox, the Uniates attempted to seize the church of St. George in Izraa, one of the oldest Christian temples in the region. To the Orthodox community it presented a threat coming from a wealthier enemy backed up by the See of Rome and the French embassy. The only ally the Antioch Patriarchate could lean on for support in the fight for its identity was the Russian Empire, a traditional protector of the Orthodox Arabs in the Middle East. The documents from the Foreign Affairs Archive of the Russian Empire, introduced to the scientific usage for the first time, present a unique opportunity to delve into the history of this conflict involving the higher officials of the Ottoman Empire as well as the Russian embassy in ConstantinopleВ статье рассматривается малоизвестный эпизод соперничества православной и Мелкитской общин в Сирии в конце XIX века. Чтобы укрепить свое превосходство над православными, униаты предприняли попытку захватить церковь Святого Георгия в Израа, один из старейших христианских храмов в регионе. Для православной общины он представлял угрозу, исходящую от более богатого врага, поддерживаемого Римским престолом и французским посольством. Единственным союзником, на которого Антиохийский патриархат мог опереться в борьбе за свою идентичность, была Российская Империя, традиционный защитник православных арабов на Ближнем Востоке. Документы из архива иностранных дел Российской Империи, введены в научный оборот впервые, уникальная возможность углубиться в историю этого конфликта с участием высших должностных лиц в Османской империи, а также российского посольства в Константинополе.

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