scholarly journals Comparison of shortest sailing distance through random and regular sampling points

2004 ◽  
Vol 61 (1) ◽  
pp. 140-147 ◽  
Author(s):  
Alf Harbitz ◽  
Michael Pennington
Keyword(s):  
Random Sampling ◽  
Minimum Distance ◽  
Barents Sea ◽  
Pandalus Borealis ◽  
The Barents Sea ◽  
Theoretical Sampling ◽  
Sampling Points ◽  
Regular Sampling ◽  
The Mean ◽  
The Difference

Abstract The shortest sailing distance through n sampling points is calculated for simple theoretical sampling domains (square and circle) as well as for a rather irregular and concavely shaped real sampling domain in the Barents Sea. The sampling sites are either located at the nodes of a square grid (regular sampling) or they are randomly distributed. For n less than ten, the exact shortest sailing distance is derived. For larger n, a traveling salesman algorithm (simulated annealing) was applied, and its bias (distance from true minimum) was estimated based on a case where the true minimum distance was known. In general, the average minimum sailing distance based on random sampling was considerably shorter than for regular sampling, and the difference increased with sample size until an asymptotic value was reached at about n=60 for a square domain. For the sampling domain in the Barents Sea used for shrimp (Pandalus borealis) abundance surveys (n=118 stations), the cruise-track lengths based on random sampling were approximately normally distributed. The mean sailing distance was 18% shorter than the cruise track for regular sampling and the standard deviation equalled 2.6%.

scholarly journals The genetic structure of Pandalus borealis in the Northeast Atlantic determined by RAPD analysis

2006 ◽  
Vol 63 (5) ◽  
pp. 840-850 ◽  
Author(s):  
Iciar Martinez ◽  
Michaela Aschan ◽  
Taran Skjerdal ◽  
Salah M. Aljanabi
Keyword(s):  
Genetic Structure ◽  
Barents Sea ◽  
Rapd Analysis ◽  
Rapd Marker ◽  
Arbitrary Primers ◽  
Pandalus Borealis ◽  
Northeast Atlantic ◽  
The Barents Sea ◽  
Local Selection ◽  
Significant Difference

Abstract The genetic structure of shrimp (Pandalus borealis) in the Northeast Atlantic was examined by RAPD analysis on specimens caught at eight stations in the Barents Sea, three off Svalbard, two off Jan Mayen, and in two northern Norwegian fjords (19 < n > 31 per station). A total of 34 polymorphic markers generated by seven 10-mer arbitrary primers was used to assess the genetic population structure using analysis of molecular variance (AMOVA). There was considerable RAPD diversity (>90%) among shrimp at all stations. The two Norwegian fjords and the Jan Mayen stations were different from all the others, and the Jan Mayen stations also differed from each other. More than 98% of the genetic variation between Barents Sea and Svalbard was ascribed to individual diversity, and there was no significant difference between the two areas, although there seemed to be a subpopulation structure in the Barents Sea. Principal component analysis on the frequency of each RAPD marker on each sampled station confirmed the presence of three populations: Barents Sea and Svalbard, northern Norwegian fjords, and Jan Mayen. We postulate that the large genetic variability found at an individual level may provide the total population with a diverse genetic pool from which traits can be selected to respond to variations in local environmental conditions, and that this local selection may be the cause of the subpopulation structure observed.

scholarly journals PENGARUH MODEL PROBLEM BASED LEARNING BERBASIS LINGKUNGAN TERHADAP HASIL BELAJAR SISWA KELAS X AP PADA MATA AJAR SANITASI, HYGIENE DAN KESELAMATAN KERJA DI SMK PARIWISATA TRIATMA JAYA SINGARAJA TAHUN AJARAN 2018/2019

2019 ◽  
Vol 10 (2) ◽  
pp. 74
Author(s):  
Yulianitias Yulianitias ◽  
Cokorda Istri Raka Marsiti ◽  
Luh Masdarini
Keyword(s):  
Random Sampling ◽  
Model Problem ◽  
Problem Based Learning ◽  
Workplace Safety ◽  
Control Group ◽  
Control Group Design ◽  
The Mean ◽  
The Difference ◽  
Level Of Significance ◽  
Academic Year

ABSTRAK Tujuan dari penelitian ini adalah untuk mengetahui perbedaan dari penggunaan model Problem Based Learning berbasis lingkungan terhadap hasil belajar siswa kelas X-AP mata ajar Sanitasi, Hygiene dan Keselamatan kerja di SMK Pariwisata Triatma Jaya Singaraja Tahun Ajaran 2018/2019. Desain penelitian yang digunakan adalah Non equivalent Only Control Group Design. Objek dalam penelitian ini terdiri dari dua kelas sampel, yaitu kelas eksperimen dan kelas kontrol. Metode pemilihan sampel penelitian adalah dengan teknik random sampling. Proses pengumpulan data menggunakan instrumen tes untuk mengetahui hasil belajar siswa, kemudian melakukan pengujian hipotesis dengan menggunakan teknik uji-t. Berdasarkan hasil analisis data, diperoleh thitung 7,641 dan ttabel (pada taraf signifikansi 5%) = 3,460. Hal ini berarti bahwa thitung> ttabel, sehingga dapat diinterpretasikan bahwa terdapat pengaruh yang signifikan terhadap hasil belajar siswa X AP Di SMK Pariwisata Triatma Jaya Singaraja antara kelompok siswa yang dibelajarkan dengan Problem Based Learning berbasis lingkungan lebih tinggi dibandingkan kelompok siswa yang dibelajarkan dengan metode konvensional. Dilihat dari hasil perhitungan rata-rata hasil belajar Sanitasi, Hygiene dan Keselamatan kerja kelompok eksperimen adalah 81 lebih besar dari rata-rata hasil belajar Sanitasi, Hygiene dan Keselamatan kerja kelompok kontrol yaitu 76 Kata kunci: Hasil belajar Sanitasi, Hygiene dan Keselamatan Kerja, Model Problem Based Learning (PBL) Berbasis Lingkungan ABSTRACT The study aimed at finding out the difference of implementation of problem based learning model with environmental basis towards the achievement of class XAP students on the subjects of sanitation, hygiene, and workplace safety at SMK Pariwisata Triatma Jaya Singaraja on the academic year 2018/2019. The research was designed with non equivalent only group control. The objects were two classes of samples, namely controlled and sample classes. Random sampling method was apllied to determine the sample of the research. The data were gathered by using test to find out the achievement of the students , then examining the hypothesis was done by implementing t-examiner technique. The results show that tvalue is 7,641 and ttable (at level of significance 5%) = 3,460. It means that tvalue> ttable. It can be interpreted that there is a significant effect towards the students’ahievement of class X AP at SMK Pariwisata Triatma Jaya Singaraja. The group of students that were treated with Problem Based Learning with the environmental basis got the mean score 81 for sanitation, hygiene, and workplace safety, it is higher than those who were treated with conventional method (controlled group).Key words : achievement, sanitation, hygiene, and workplace safety Model

Do abiotic mechanisms determine interannual variability in length-at-age of juvenile Arcto-Norwegian cod?

2002 ◽  
Vol 59 (1) ◽  
pp. 57-65 ◽  
Author(s):  
Geir Ottersen ◽  
Kristin Helle ◽  
Bjarte Bogstad
Keyword(s):  
Growth Rates ◽  
Gadus Morhua ◽  
Barents Sea ◽  
Water Masses ◽  
Inverse Relation ◽  
Lower Growth ◽  
Density Dependent ◽  
The Barents Sea ◽  
The Mean ◽  
Dependent Growth

For the large Arcto-Norwegian stock of cod (Gadus morhua L.) in the Barents Sea, year-to-year variability in growth is well documented. Here three hypotheses for the observed inverse relation between abundance and the mean length-at-age of juveniles (ages 1–4) are suggested and evaluated. Based on comprehensive data, we conclude that year-to-year differences in length-at-age are mainly determined by density-independent mechanisms during the pelagic first half year of the fishes' life. Enhanced inflow from the southwest leads to an abundant cohort at the 0-group stage being distributed farther east into colder water masses, causing lower postsettlement growth rates. We can not reject density-dependent growth effects related to variability in food rations, but our data do not suggest this to be the main mechanism. Another hypothesis suggests that lower growth rates during periods of high abundance are a result of density-dependent mechanisms causing the geographic range of juveniles to extend eastwards into colder water masses. This is rejected mainly because year-to-year differences in mean length are established by age 2, which is too early for movements over large distances.

scholarly journals Bycatch reduction in the deep-water shrimp (Pandalus borealis) trawl fishery by increasing codend mesh openness

2021 ◽  
Author(s):  
Nadine Jacques ◽  
Hermann Pettersen ◽  
Kristine Cerbule ◽  
Bent Herrmann ◽  
Ólafur A. Ingólfsson ◽  
...  
Keyword(s):  
Deep Water ◽  
Barents Sea ◽  
Juvenile Fish ◽  
Size Selectivity ◽  
Pandalus Borealis ◽  
Trawl Fishery ◽  
Bycatch Reduction ◽  
Drag Forces ◽  
The Barents Sea ◽  
Trawl Fisheries

In most trawl fisheries, drag forces tend to close the meshes in large areas of diamond mesh codends, negatively affecting their selective potential. In the Barents Sea deep-water shrimp (Pandalus borealis) trawl fishery, selectivity is based on a sorting grid followed by a diamond mesh codend. However, the retention of juvenile fish as well as undersized shrimp is still a problem. In this study, we estimated the effect of applying different codend modifications, each aimed at affecting codend mesh openness and thereby selectivity. Changing from a 4-panel to a 2-panel construction of the codend did not affect size selectivity. Shortening the lastridge ropes of a 4-panel codend by 20% resulted in minor reductions for juvenile fish bycatch, but a 45% reduction of undersized shrimp was observed. Target-size catches of shrimp were nearly unaffected. When the codend mesh circumference was reduced while simultaneously shortening the lastridge ropes, the effect on catch efficiency for shrimp or juvenile fish bycatch was marginal compared to a 4-panel codend design with shortened lastridge ropes.

Distinguishing between Different Populations of Harp Seal (Phoca groenlandica) by Chemometry of the Fatty Acid Profiles in the Jaw Bone

1993 ◽  
Vol 50 (7) ◽  
pp. 1400-1404 ◽  
Author(s):  
Otto Grahl-Nielsen ◽  
Olav Mjaavatten ◽  
Einar Tvedt
Keyword(s):  
Fatty Acid ◽  
Barents Sea ◽  
Principal Component ◽  
Eye Lens ◽  
Fatty Acid Profiles ◽  
Phoca Groenlandica ◽  
The Barents Sea ◽  
Different Populations ◽  
The Difference ◽  
Two Populations

The relative amounts of various fatty acids of jawbone and eye lens were determined in harp seals (Phoca groenlandica) caught in the Greenland Sea and in the Barents Sea. The two tissues had distinctly different profiles. The fatty acid profile in the lens tissue changed with age. Principal component analysis of the data showed that the profiles in the jawbone were different in seals from the two populations, while the difference was much less prominent in the case of the eye lens. Using the jawbone profiles from the western and eastern seals as reference, it was shown that seven seals, caught in west coast seine nets during the large invasion of harp seals along the Norwegian coast in the winter of 1986–87, had come from the eastern population.

scholarly journals The Barents Sea euphausiids: methodological aspects of monitoring and estimation of abundance and biomass

2016 ◽  
Vol 73 (6) ◽  
pp. 1533-1544 ◽  
Author(s):  
Elena Eriksen ◽  
Hein Rune Skjoldal ◽  
Andrey V. Dolgov ◽  
Padmini Dalpadado ◽  
Emma L. Orlova ◽  
...  
Keyword(s):  
Barents Sea ◽  
Warming Trend ◽  
Atlantic Water ◽  
Great Promise ◽  
The Barents Sea ◽  
Intermediate Size ◽  
Wet Weight ◽  
The Mean ◽  
Marine Areas ◽  
Methodological Aspects

Abstract Sampling of euphausiids is difficult because of their intermediate size between macrozooplankton and micronekton. The Barents Sea is one of the few marine areas where there have been long-term studies of euphausiids. We have examined three monitoring datasets on euphausiids and consider likely sources of errors associated with the sampling. Results indicated a high degree of patchiness in the distribution of euphausiids, even at the largest scale of sampling with a pelagic trawl. This indicates that euphausiids may occur in large, but infrequent, swarms that have a low probability of being sampled by small nets. The mean biomass of euphausiids sampled with MOCNESS was 2 g wet weight m−2 integrated over the water column, which is an underestimate due to avoidance of large individuals. The mean biomass obtained with pelagic trawl in the upper 60 m of water at night during an autumn survey was 10 g wet weight m−2. The plankton net on bottom trawl collected mean and median density of euphausiids (0.1–0.2 g wet weight m−3) near bottom during a winter survey similar to the values found with pelagic trawl in the upper layer during autumn. The mean density for the autumn survey showed an increase from 2000 to 2011, while the winter survey showed generally a decrease from 2000–2007 to 2011. The increase in the autumn series coincided with a general warming trend presumably with a larger influx of euphausiids with Atlantic water, notably of Meganyctiphanes norvegica. In contrast, the decline during winter may reflect a decrease, particularly of Thysanoessa raschii in the southeastern Barents Sea in the most recent years. Improvements in sampling gears combined with more and better use of acoustical and optical technologies offer great promise for improved monitoring and quantification of the roles of euphausiids in the Barents Sea ecosystem.

scholarly journals Ice Properties in the Greenland and Barents Seas During Summer

1983 ◽  
Vol 29 (101) ◽  
pp. 142-164 ◽  
Author(s):  
Søren Overgaard ◽  
Peter Wadhams ◽  
Matti Leppäranta
Keyword(s):  
Barents Sea ◽  
Ionic Composition ◽  
Ice Cores ◽  
The Arctic ◽  
Ice Thickness ◽  
First Year ◽  
The Barents Sea ◽  
Brine Volume ◽  
European Arctic ◽  
The Difference

Abstract The analysis of sea-ice cores from three summer field operations to the European Arctic is reported, and the ice properties are related to general conditions of ice distribution, thickness, and ridging in the experimental areas. The operations were in 1978 and 1979 to the Kong Oscars Fjord area of East Greenland (about lat. 72° N.) and in 1980 to the Barents Sea, Fram Strait, and the Arctic Ocean north of Svalbard and Zemlya Frantsa Iosifa on the Swedish Ymer-80 expedition. Salinity profiles show the effect on multi-year floes of a year’s additional confinement in a fjord, the effect of a month’s desalination (July to August) on first-year and multi-year ice, and the difference between first-year and multi-year ice at the end of the melt season. The average salinity as a function of ice thickness agrees reasonably well with the results of Cox and Weeks (1974). Temperature, density, pH, and ionic composition results are also reported, and the effect of brine volume on dielectric constant discussed.

scholarly journals The Role of Barents Sea Ice in the Wintertime Cyclone Track and Emergence of a Warm-Arctic Cold-Siberian Anomaly

2012 ◽  
Vol 25 (7) ◽  
pp. 2561-2568 ◽  
Author(s):  
Jun Inoue ◽  
Masatake E. Hori ◽  
Koutarou Takaya
Keyword(s):  
Sea Ice ◽  
Barents Sea ◽  
The Arctic ◽  
Cyclone Track ◽  
Anticyclonic Anomaly ◽  
The Barents Sea ◽  
Cold Events ◽  
The Difference ◽  
Siberian Coast

Abstract Sea ice variability over the Barents Sea with its resultant atmospheric response has been considered one of the triggers of unexpected downstream climate change. For example, East Asia has experienced several major cold events while the underlying temperature over the Arctic has risen steadily. To understand the influence of sea ice in the Barents Sea on atmospheric circulation during winter from a synoptic perspective, this study evaluated the downstream response in cyclone activities with respect to the underlying sea ice variability. The composite analysis, including all cyclone events over the Nordic seas, revealed that an anticyclonic anomaly prevailed along the Siberian coast during light ice years over the Barents Sea. This likely caused anomalous warm advection over the Barents Sea and cold advection over eastern Siberia. The difference in cyclone paths between heavy and light ice years was expressed as a warm-Arctic cold-Siberian (WACS) anomaly. The lower baroclinicity over the Barents Sea during the light ice years, which resulted from a weak gradient in sea surface temperature, prevented cyclones from traveling eastward. This could lead to fewer cyclones and hence to an anticyclonic anomaly over the Siberian coast.

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