scholarly journals The Problem of Removing Seaweed from the Beaches: Review of Methods and Machines

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 736
Author(s):  
Łukasz Warguła ◽  
Bartosz Wieczorek ◽  
Mateusz Kukla ◽  
Piotr Krawiec ◽  
Jakub Wojciech Szewczyk

Beach cleaning and algae collection in the shoreline area are important for the tourism industry, mainly for aesthetic reasons, but also to protect human health. In addition, the collected material can be used in many industries such as energy, medicine, cosmetics or catering. The problem of cleaning the shoreline area concerns the need to clear land, water and the strip of shore and land onto which water is thrown from falling waves. The vast majority of available cleaning methods are adapted to cleaning beaches or waters. There is a lack of solutions and machine designs suitable for cleaning the coastal strip, which includes: land, the area of land on which the wave is thrown, shoal and deep water. This area is particularly important for tourism as it is mainly used for water bathing. Pictures from tourist areas that are exposed to intensive water contamination show that measures taken to clear the shoreline area are not very effective, as seaweed in shallow water is thrown ashore with the waves. The paper presents a review of methods for cleaning coastal waters and beaches from contamination. It also shows the author’s conceptual design adapted to clear the shoreline area and sandy beaches.

Author(s):  
Joanes E Koagouw ◽  
Gybert E Mamuaya ◽  
Adrie A Tarumingkeng ◽  
P A Angmalisang

Coastal area of Bitung Municipality is one of the economical activities centers in North Sulawesi Province such as for land-uses and the exploitation of natural resources. Those activities are exaggerating day bay day and tended to be uncontrollable. The excess of those conditions, it has been recorded the change of waves in Bitung waters that has impacts to coastal areas and can affect the utilization of coastal and marine resources. This research was aimed to observe waves altitude variations in Bitung waters with Svedrup Munk and Bretchsneider (SMB) method that had been used to predict waves altitudes. The results showed that the wind speed during West Season was 0.33 m and were dominant to the East, while during East season was 0.91m from South-East to North-West, and then on transition period (March to May) was 1.08m from South-East to East. The results of those wind speed to the waves altitudes in Bitung waters is discussed in this paper© Pesisir pantai Kota Bitung merupakan salah satu pusat aktivitas ekonomi (misalnya pemanfaatan lahan dan eksploitasi sumberdaya) di Provinsi Sulawesi Utara. Aktivitas tersebut semakin hari semakin meningkat dan memiliki kecenderungan tidak terkontrol. Akibat dari keadaan tersebut, telah terjadi perubahan fenomena gelombang di perairan Bitung yang berdampak pada keberadaan daerah pesisir pantai di mana hal ini dapat mengganggu aktivitas pemanfaatan sumberdaya pesisir dan laut tersebut. Penelitian ini bertujuan untuk mengetahui variasi tinggi gelombang di perairan Bitung dengan menggunakan metode Svedrup Munk and Bretchsneider (SMB) yang biasa digunakan untuk peramalan tinggi gelombang signifikan. Hasil penelitian menunjukkan bahwa kecepatan angin pada Musim Barat sebesar 0,33 meter dan dominan ke arah Timur, sementara pada Musim Timur sebesar 0,91 meter dari arah Tenggara ke Barat Laut, serta pada Musim Peralihan (antara bulan Maret-Mei) adalah sebesar 1,08 meter dari arah Tenggara dan Timur. Pengaruh kecepatan angin tersebut terhadap gelombang laut di perairan Bitung dibahas dalam tulisan ini©


Author(s):  
Svetlana Rubtsova ◽  
Svetlana Rubtsova ◽  
Natalya Lyamina ◽  
Natalya Lyamina ◽  
Aleksey Lyamin ◽  
...  

The concept of a new approach to environmental assessment is offered in the system of integrated management of the resource and environmental safety of the coastal area of the Black Sea. The studies of the season and daily changeability in the bioluminescence field in the Sevastopol coastal waters has been conducted. For the first time considerable differences in the bioluminescence field seasonal changes in the surface and deep water layers and the reasons conditioning this phenomenon have been shown, using a method of multidimensional statistical analysis. The bioluminescence field vertical profile change in the Black sea coastal waters in the autumn period at night has been studied. It has been shown that according to the character of bioluminescence parameters dynamics a water column can be divided into layers: upper (0 – 35 m) and deep water (36 – 60 m). It has been revealed that life rhythms of the plankton community are the main reason for the bioluminescence field intensity variability. It has been revealed that 14-hour periodicity of the bioluminescence field is related to the changes in light and its variations with 2,5…4,5 hours are conditioned by planktonts endogenous daily rhythms. And here biotic factors effect mostly periodicity of the bioluminescence field intensity increase and fall down at the dark time of the day. Abiotic factors are of less importance in circadian rhythmic of the bioluminescence field in the neritic zone.


1971 ◽  
Vol 50 (2) ◽  
pp. 321-334 ◽  
Author(s):  
James Witting

The average changes in the structure of thermal boundary layers at the surface of bodies of water produced by various types of surface waves are computed. the waves are two-dimensional plane progressive irrotational waves of unchanging shape. they include deep-water linear waves, deep-water capillary waves of arbitrary amplitude, stokes waves, and the deep-water gravity wave of maximum amplitude.The results indicate that capillary waves can decrease mean temperature gradients by factors of as much as 9·0, if the average heat flux at the air-water interface is independent of the presence of the waves. Irrotational gravity waves can decrease the mean temperature gradients by factors no more than 1·381.Of possible pedagogical interest is the simplicity of the heat conduction equation for two-dimensional steady irrotational flows in an inviscid incompressible fluid if the velocity potential and the stream function are taken to be the independent variables.


Author(s):  
Rodrigo A. Barreira ◽  
Vinicius L. Vileti ◽  
Joel S. Sales ◽  
Sergio H. Sphaier ◽  
Paulo de Tarso T. Esperança

A new conceptual design of a deepwater MONOBUOY, named DeepWater MultiColumn Buoy (DWMCB), patent PCT/BR2011/000133, was developed by PETROBRAS/CENPES. The DWMCB was designed to be part of an offloading system for a Spread Moored Floating Production Offloading Unit (FPSO). The offloading system principle consists of Oil being exported from the FPSO to a Shutle tanker passing through Offloading Oil Lines (OOLs) that are supported by the DWMCB. The system is designed to operate at a water depth of 2,200 meters, with expected in site life duration of 25 years. The geometry of DWMCB was defined after an optimization process in order to minimize its motions. This paper describes the development of this concept and discusses the results from some design verifications done with the help of a model tests campaign. An equivalent traditional shaped monobuoy was also tested for comparison purposes.


Author(s):  
Shelley Wachsmann

Coastal waters represent the greatest danger to ships and seafarers, as ships are most commonly lost at the intersection of water and shore. Ships sinking in deep water undergo a gradual transition. Deep-submergence archaeology refers to the archaeological study of cultural resources beyond the limits of traditional diving. The totality of archaeological exploration at great depths—discovering, recording, excavating, and recovering—requires function-specific tools. Deep Submergence Archaeological Excavations (DSAE) takes advantage of a remarkable existent toolkit, designed for a variety of oceanographic purposes other than the study of ancient shipwrecks. What is lacking at present is a comprehensive methodology for deepwater excavation. The ultimate goal of DSAE is to develop the technologies and the skills that permit expeditions to excavate and safely raise the contents and hull of an entire ship for conservation, study, and display.


2016 ◽  
Vol 51 (4) ◽  
pp. 613-625
Author(s):  
Jung-Im Park ◽  
Jong-Hyeob Kim ◽  
Su Hyun Park

2008 ◽  
Vol 35 (6) ◽  
pp. 662-667 ◽  
Author(s):  
N. A. Bakunov ◽  
D. Yu. Bol’shiyanov ◽  
A. S. Makarov

Author(s):  
Anne Katrine Bratland ◽  
Ragnvald Bo̸rresen ◽  
Per Ivar Barth Berntsen

Wave-current interaction refers to the interaction between surface gravity waves and ocean current flow. This interaction implies an exchange of energy, i.e. both the waves and the current are affected. The present paper describes the calculation of wave elevations in higher order unidirectional, irregular waves with a uniform current in deep water. Results for regular waves are compared with those obtained for Stokes second and third order waves with uniform current according to the method described by Fenton [1]. The results for higher order wave elevations in irregular waves have been compared with waves and current generated in a model test basin and reasonable agreement has been found.


1968 ◽  
Vol 21 (1) ◽  
pp. 91-91
Author(s):  
J. A. Ewing

I would like to comment on the change in underkeel clearance due to the motion of a ship in a seaway (A. F. Dickson, this Journal, 20, 363).Captain Dickson, in his conclusions, states that known techniques do not allow underkeel clearance to be calculated when ship motion is present. In fact there are a number of reliable ways of calculating the motions of a ship in waves (for example References (1) and (2), which treat the case of pitch and heave) which may help in this problem. These methods usually assume the ship is in deep water and is heading directly into the waves which are further assumed to be long-crested; but I believe it may also be possible to make reliable calculations for shallow-water effects and for waves which are, in reality, short-crested.


1996 ◽  
Vol 74 (8) ◽  
pp. 1313-1321 ◽  
Author(s):  
Mary Yanful ◽  
M. A. Maun

Field studies were conducted to determine the survival, seed-mass variability, and reproductive strategies of wild bean, Strophostyles helvola (L.) Ell., plants on the foredunes at Port Burwell Provincial Park along Lake Erie. In spring, a large number of seedlings were found on the drift-line (area of beach where detritis deposits are cast on shore by the waves) and a small number both on the lakeward (mid-beach) and landward (high-beach) ends of the drift-line. Plants growing on the mid-beach were larger and produced a significantly greater number of heavier seeds than those on the drift-line. However, during late fall and winter months, a large proportion of these seeds were moved by wind and wave action to the drift-line. Intraspecific competition was not a limiting factor on the mid-beach; however, on the drift-line, the number of seeds per plant decreased significantly with an increase in density of plants from about 1 to 140/m2, suggesting that intraspecific competition may be an important limiting factor in seed production per plant. The mean mass per seed significantly declined over the growing season of S. helvola. There was a significant increase in mean seed mass with increasing pod size. Seeds in the centre of a pod were significantly heavier than those at the proximal and distal ends of a pod. Strophostyles helvola is able to flourish in the constantly shifting shoreline beach habitats along Lake Erie owing to two main factors. First, it is able to fully utilize the highly variable beach microhabitats and maintain high total reproductive output per square metre. Second, since burial in sand is a major recurrent event on sandy beaches, the high variability in seed mass will be of adaptive significance because seedlings from large seeds will not only be able to emerge from greater depths of burial in sand but also will have greater probability of survival under burial conditions. Keywords: seed mass, plant location, Strophostyles helvola, seed position, spatial distribution.


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