scholarly journals Validasi Sebaran Kapal Penangkap Ikan Tradisional Menggunakan Data Penginderaan Jauh Dan GPS Tracker

2017 ◽  
Vol 4 (1) ◽  
pp. 14
Author(s):  
Komang Iwan Suniada
Keyword(s):  
Satellite Data ◽  
Radar Data ◽  
Fishing Vessel ◽  
Ground Station ◽  
Iuu Fishing ◽  
Accuracy Test ◽  
Fishing Vessels ◽  
Position Data ◽  
Radar Satellite ◽  
Traditional Fishing

Utilization of radar satellite data to monitoring vessels distribution in regard to combating IUU fishing is a newly developed in Indonesia. Ship detection using radar satellite data performed with high accuracy which is about 79% to the size of the boats between 24-81 meters (averaging 45 meters).  However, information about accuracy of the radar satellites to detect small traditional fishing vessel are not yet widely available, and making this study is very important to conducted.    The research was conducted at the west part of Belitung Island waters using RADARSAT-2 satellite data to detect vessels distribution which was acquired by radar ground station Perancak at October 25, 2016 and also using vessel position data which is acquired by using GPS tracker.  There are 10 traditional fishing vessel was used as a sample, in accordance with the availability of GPS tracker.  All vessels are made from wood with the size between 11 to 15 meter and using ‘bubu’ as a primary fishing gear to catch fish.  Accuracy test was done using overlay analysis between vessel distribution information resulted from radar image analysis with the vessel position data coming from the GPS Tracker.  Result showed that the accuracy of radar data on extended high incidence beam mode to detect the distribution of traditional fishing vessels with small size (11-15 meters) is about 30% and over estimate measuring between 7.5 to 8 meters.

scholarly journals Level of Compliance of Traditional Fishing Vessels to Fisheries Department Regulations in Pangkor Island

2019 ◽  
Vol 9 (2) ◽  
pp. 4585-4589
Keyword(s):  
Content Analysis ◽  
Qualitative Content Analysis ◽  
Likert Scale ◽  
Fishing Vessel ◽  
Statistical Tools ◽  
Fishing Vessels ◽  
Traditional Fishing ◽  
Frequent Reason

This study aims to determine the level of compliance of fishing vessels operations to Malaysian Fisheries Department rules and regulations as well as to identify the reasons of non-compliance among fishermen in Pangkor Island, Perak. The data was collected through the distribution of questionnaire and analysed using descriptive statistical tools. The level of compliance of fishing vessel operations was determined by a five point Likert scale, whilst qualitative statements were grouped into several topics using qualitative content analysis. The reasons for the fishermen’s non-compliance were also identified by using closed-ended and open-ended questions. The outcome of this study can be categorised into several levels of compliance. As for the reasons for non-compliance, the most frequent reason chosen by respondents was lack of trust towards the authorities.

River morphological changes detection from drone and radar satellite data

2020 ◽  
Author(s):  
Giulia Marchetti ◽  
Francesco Asaro ◽  
Simone Bizzi ◽  
Stefano Mariani ◽  
Barbara Lastoria ◽  
...  
Keyword(s):  
Satellite Data ◽  
Large Scale ◽  
Morphological Changes ◽  
Atmospheric Condition ◽  
Radar Data ◽  
Radar Signal ◽  
Catchment Scale ◽  
Natural Risk ◽  
Sediment Size ◽  
Radar Satellite

<p>The identification and quantification of morphological changes occurring in the river channel over time are essential to understand rivers behaviour, assess sediment budgets, evaluate effectiveness of river management strategies and support the production of natural risk map. Recently, river science has made a breakthrough thanks to emerging remote sensing technologies and today we can rely on an unparalleled amount of data, at spatial and temporal resolution not available in the past. This has opened new perspectives for river monitoring and fluvial survey practices, allowing to cover areas up to the catchment scale and get information almost in continuum. This research aims to investigate the potential of radar satellite data collected from Sentinel 1 mission to infer information about rivers morphodynamics processes (such as erosion and deposition), that may occur on medium-large river (e.g., active channel width > 50 m) after a flood that caused significant morphological adjustments. Drone and satellite data were collected in September 2017 and September 2018 on a selected site along the Po river, in northern Italy, characterized by a large exposed sediment bar. In March 2018 a flood caused an avulsion and a new secondary channel was opened. We used the sequential drone acquisitions to generate a Dem of Difference, that revealed geomorphic changes of the monitored sediment bar up to 2 m erosion and 1.5 m deposition. We then exploited the radar data of Sentinel 1 and conducted a seasonal analysis using both the coherence data between image pairs and the backscattered radar signal, by investigating the variability of the radar signals through the year and the correspondent condition of the bar. Results show that there is a significant correlation between morphological changes occurred in the site and the associated values of both the amplitude and the coherence of the radar data pre and post the event that caused the morphological changes measured. Further studies are needed to better discriminate the different contributions to changes in amplitude and coherence driven by soil water content, vegetation, sediment size, atmospheric condition for the various time windows analysed. Despite that, these initial evidences are encouraging and new applications to other sites and flood events are planned because these results prove the sensitiveness of the radar signal to geomorphic events. Even simply the ability to detect where channel morphological processes are occurring and their expected intensity through Sentinel 1 data would allow to prioritize more detailed field campaigns by, for instance, UAV technology providing a notable advance compared to the current ability to monitor river morphological changes on large scale.</p>

scholarly journals Fisheries: A Missing Link in Greenhouse Gas Emission Policies in South Korea

2021 ◽  
Vol 13 (11) ◽  
pp. 5858
Author(s):  
Kyumin Kim ◽  
Do-Hoon Kim ◽  
Yeonghye Kim
Keyword(s):  
Greenhouse Gas ◽  
Greenhouse Gas Emission ◽  
Ghg Emissions ◽  
Bioeconomic Model ◽  
Negative Externalities ◽  
Fishing Vessel ◽  
Gas Emission ◽  
Fishing Vessels ◽  
The Government ◽  
Different Levels

Recent studies demonstrate that fisheries are massive contributors to global greenhouse gas (GHG) emissions. The average Korean fishing vessel is old, fuel-inefficient, and creates a large volume of emissions. Yet, there is little research on how to address the GHG emissions in Korean fisheries. This study estimated the change in GHG emissions and emission costs at different levels of fishing operations using a steady-state bioeconomic model based on the case of the Anchovy Tow Net Fishery (ATNF) and the Large Purse Seine Fishery (LPSF). We conclude that reducing the fishing efforts of the ATNF and LPSF by 37% and 8% respectively would not only eliminate negative externalities on the anchovy and mackerel stock respectively, but also mitigate emissions and emission costs in the fishing industry. To limit emissions, we propose that the Korean government reduce fishing efforts through a vessel-buyback program and set an annual catch limit. Alternatively, the government should provide loans for modernizing old fishing vessels or a subsidy for installing emission abatement equipment to reduce the excessive emissions from Korean fisheries.

scholarly journals KERUGIAN SUMBER DAYA IKAN AKIBAT PRAKTIK MARK DOWN KAPAL PENANGKAP IKAN DI INDONESIA

2018 ◽  
Vol 12 (2) ◽  
pp. 133
Author(s):  
Maulana Firdaus ◽  
Yesi Dewitasari ◽  
Radityo Pramoda ◽  
Sonny Koeshendrajana
Keyword(s):  
Good Governance ◽  
Secondary Data ◽  
Resource Depletion ◽  
Economic Loss ◽  
Study Data ◽  
Production Model ◽  
Fishing Vessel ◽  
Sustainable Fisheries ◽  
Fish Resources ◽  
Iuu Fishing

Dampak praktik Illegal Unreported and Unregulated Fishing (IUUF) telah mengakibatkan terganggunya pengelolaan pemanfaatan perikanan yang berkelanjutan dan menimbulkan kerugian ekonomi. Praktik mark down ukuran kapal penangkapan ikan merupakan salah satu penyalahgunaan perizinan dalam konteks praktik IUUF. Penelitian ini bertujuan untuk mengkaji nilai kerugian sumber daya ikan (deplesi sumber daya) akibat praktik “mark down” ukuran kapal penangkap ikan yang dilakukan di Indonesia. Penelitian dilaksanakan pada bulan Maret – April 2017 bersifat ‘desk study’ dan dilengkapi dengan kajian literature terkait. Data sekunder dan primer digunakan dalam penelitian ini. Analisis data dilakukan melalui Pendekatan Surplus Produksi Model Schaefer digunakan dalam penelitian ini. Nilai kerugian sumber daya ikan diketahui berdasarkan nilai deplesinya. Nilai deplesi sumber daya menggunakan pendekatan The Net Price Method. Hasil penelitian menunjukkan bahwa adanya praktik “mark down” telah menyebabkan deplesi sumber daya ikan atau pengurangan aset sumber daya ikan di perairan Indonesia. Besarnya nilai deplesi sumber daya pada tahun 2015 mencapai 9,83 trilyun rupiah dan diprediksi pada tahun 2020 meningkat menjadi 14,55 trilyun rupiah. Kajian merekomendasikan perlunya percepatan pengukuran ulang kapal perikanan dan penerapan sangsi yang tegas terhadap pelanggar sehingga tata kelola pemanfaatan sumber daya perikanan tangkap yang baik yang mampu mewujudkan pengelolaan perikanan yang berkelanjutan di Indonesia. Tittle: Fish Resources Losses Due to Mark Down Fishing Vessel Practiced in IndonesiaThe impact of IUU fishing has resulted in management disorder of sustainable fisheries and it caused economic loss. Markdown in vessels size is one type of manipulation practices of license in IUU fishing. This study aims to analyze the loss value of fish resources (resource depletion) due to the “markdown” practices in Indonesia. The study was basically a desk study completmenting with relevant literatures review during March – April 2015. Primary and secondary data were used in this study. Data were analyzed using the Schaefer surplus production model approached. Loss value of fish resources was estimated in terms of depletion resource value using the Net Price Method. The research found that “mark down” has led to depletion or reduction of fish resources in Indonesian waters. The estimated value of resource depletion in 2015 reached 9.83 trillion rupiahs and it is predicted to rise into 14.55 trillion rupiahs in 2020. The research suggests the need to accelerate the process of re-measuring the size of fishing vessel as well as to impose sanctions for the disobedience of the rules, so that Indonesia could have a good governance in fisheries resource management with sustainable fisheries resources.

scholarly journals PERBANDINGAN KAPAL MONOHULL, CATAMARAN, TRIMARAN BERDASARKAN TINJAUAN OPERASIONAL PENGGUNAAN BAHAN BAKAR

2021 ◽  
Vol 4 ◽  
pp. 30-36
Author(s):  
Jacobus Tupan ◽  
Richard Benny Luhulima
Keyword(s):  
Data Analysis ◽  
Energy Requirements ◽  
Energy Usage ◽  
Fishing Vessel ◽  
Fishing Vessels ◽  
Initial Stage ◽  
Transverse Stability ◽  
Fishing Fleets

In general, fishing fleets operating in Maluku waters and managed by local entrepreneurs consist of monohull and trimaran fishing vessels with outriggers. Monohull fishing vessels have limited deck space and poor transverse stability, while trimaran-type vessels have better deck space and transverse stability than monohull vessels, but because they are still in the form of outriggers, the space is limited. This study aims to examine the development of the trimaran fishing vessel in terms of energy requirements, safety, and comfort of the crew during fishing operations. The initial stage of this research begins with data analysis and the basic size of monohull fishing vessels operating in Maluku waters, from this data the shape of the trimaran hull is designed. Calculation of resistance using CFD, then analyzed the calculation of resistance and stability, safety, and comfort of the ship using Maxsurf. The drag Trimaran is 8.86% smaller than a monohull and 3.25% smaller than a catamaran. Energy Usage (EHP) is proven by trimaran ships more than other ship modes. The average trimaran period is 10.5 seconds which meets IMO standards and is declared operationally good.

scholarly journals ANALISA TITIK KRITIS GERAKAN ROLL KAPAL TRIMARAN UNTUK DIAPLIKASI PADA KAPAL IKAN PURSE SEINE

2021 ◽  
Vol 4 ◽  
pp. 44-50
Author(s):  
Fella Gaspersz ◽  
Richard B. Luhulima
Keyword(s):  
Critical Point ◽  
Wave Height ◽  
Inclination Angle ◽  
Weather Conditions ◽  
Extreme Weather ◽  
Roll Motion ◽  
Fishing Vessel ◽  
Fishing Vessels ◽  
Wave Heights ◽  
Wave Angle

The marine fisheries catching and processing industry are considered vulnerable to the effects of extreme weather at sea. Global warming effects and El Nino and La Nina have a significant impact on the upwelling process, which impacts the lifestyle and environment of marine biota, including pelagic fish, which is one of the most important contributors to the shipping industry. Extreme weather conditions, with wave heights ranging from 1 to 5 meters, dominate the waters of Maluku. In extreme sea conditions, most fishers choose not to go fishing, not because there are no fish at the fishing grounds, but to avoid mishaps at sea. This research aimed to analyze the critical point of ship roll motion and ship stability. The hull shape employed in this study was a monohull fishing vessel and a trimaran fishing vessel with the same displacement of 21,1 tons. In extreme weather conditions, the Maxsurf software was used to analyze the ship's response, especially the critical point of the ship's roll motion. The I.M.O. Standard was utilized to calculate the ship's stability. The operational speed of the ship was v = 3 knots, with fluctuations in wave angle of incidence between 00 - 1800. Wave heights of 1,0; 2,0; 3,0, and 0,4 meters represent extreme weather conditions in Maluku waters' fishing grounds. The findings revealed that the trimaran hull type had better stability where the inclination angle of trimaran vessel stability was 480 while the monohull was 410. The trimaran fishing vessel was able to withstand a wave height of 3 meters with an inclination angle of 32,560. In comparison, the monohull fishing vessel was able to survive at a wave height of 2 meters with an inclination angle of 24,690. Monohull fishing vessel had a maximum limit of roll motion at wave directions 82 and 99 with a wave height of 3 m, and it reached at the critical point at angles of 43 and 138, at the height of 4 m. Meanwhile, the trimaran fishing vessel had a critical point at a wave angle of 760 and 1000 with a wave height of 4 meters. In the area between those two angles, monohull and trimaran fishing vessels will lose the balance (stability) of the roll motion, resulting in capsize.

scholarly journals Comparison of the cloud top heights retrieved from MODIS and AHI satellite data with ground-based Ka-band radar

2019 ◽  
Author(s):  
Juan Huo ◽  
Daren Lu ◽  
Shu Duan ◽  
Yongheng Bi ◽  
Bo Liu
Keyword(s):  
Satellite Data ◽  
Radar Data ◽  
Retrieval Algorithm ◽  
Ka Band ◽  
Retrieval Accuracy ◽  
Retrieval Algorithms ◽  
Moderate Resolution ◽  
Resolution Imaging ◽  
Radar Measurements ◽  
Moderate Resolution Imaging Spectroradiometer

Abstract. To better understand the accuracy of cloud top heights (CTHs) derived from passive satellite data, ground-based Ka-band radar measurements from 2016 and 2017 in Beijing were compared with CTH data inferred from the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Advanced Himawari Imager (AHI). Relative to the radar CTHs, the MODIS CTHs were found to be underestimated by −1.10 ± 2.53 km and 49 % of CTH differences were within 1.0 km. Like the MODIS results, the AHI CTHs were underestimated by −1.10 ± 2.27 km and 42 % were within 1.0 km. Both the MODIS and AHI retrieval accuracy depended strongly on the cloud depth (CD). Large differences were mainly occurring for the retrieval of thin clouds of CD  1 km, the CTH difference decreased to −0.48 ± 1.70 km for MODIS and to −0.76 ± 1.63 km for AHI. MODIS CTHs greater than 6 km showed better agreement with the radar data than those less than 4 km. Statistical analysis showed that the average AHI CTHs were lower than the average MODIS CTHs by −0.64 ± 2.36 km. The monthly accuracy of both retrieval algorithms was studied and it was found that the AHI retrieval algorithm had the largest bias in winter while the MODIS retrieval algorithm had the lowest accuracy in spring.

scholarly journals Use of satellite data for detecting icebergs and evaluating the iceberg threats

2018 ◽  
Vol 58 (4) ◽  
pp. 537-551 ◽  
Author(s):  
I. A. Bychkova ◽  
V. G. Smirnov
Keyword(s):  
Satellite Data ◽  
Radar Data ◽  
Arctic Shelf ◽  
The Arctic ◽  
Satellite Monitoring ◽  
Landsat 8 ◽  
Space Resolution ◽  
Detection Techniques ◽  
Satellite Radar ◽  
High Space

Te methods of satellite monitoring of dangerous ice formations, namely icebergs in the Arctic seas, representing a threat to the safety of navigation and economic activity on the Arctic shelf are considered. Te main objective of the research is to develop methods for detecting icebergs using satellite radar data and high space resolution images in the visible spectral range. Te developed method of iceberg detection is based on statistical criteria for fnding gradient zones in the analysis of two-dimensional felds of satellite images. Te algorithms of the iceberg detection, the procedure of the false target identifcation, and determination the horizontal dimensions of the icebergs and their location are described. Examples of iceberg detection using satellite information with high space resolution obtained from Sentinel-1 and Landsat-8 satellites are given. To assess the iceberg threat, we propose to use a model of their drif, one of the input parameters of which is the size of the detected objects. Tree possible situations of observation of icebergs are identifed, namely, the «status» state of objects: icebergs on open water; icebergs in drifing ice; and icebergs in the fast ice. At the same time, in each of these situations, the iceberg can be grounded, that prevents its moving. Specifc features of the iceberg monitoring at various «status» states of them are considered. Te «status» state of the iceberg is also taken into account when assessing the degree of danger of the detected object. Te use of iceberg detection techniques based on satellite radar data and visible range images is illustrated by results of monitoring the coastal areas of the Severnaya Zemlya archipelago. Te approaches proposed to detect icebergs from satellite data allow improving the quality and efciency of service for a wide number of users with ensuring the efciency and safety of Arctic navigation and activities on the Arctic shelf.

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