2010 IEEE/OES Baltic International Symposium (BALTIC)最新文献

{"title":"SAR imagery and Seatrack Web as decision making tools for illegal oil spill combating — a case study","authors":"S. Anderson, R. Uiboupin, Svetlana Verjovkina, U. Raudsepp","doi":"10.1109/BALTIC.2010.5621629","DOIUrl":"https://doi.org/10.1109/BALTIC.2010.5621629","url":null,"abstract":"The number of marine pollution arising from illegal oil discharges from ship tank or bilge pumping is much greater than those spectacular ship accidents. Illegal spills are mainly detected on essential navigation routes. In every country, marine surveillance agencies are responsible for oil spill combating and on identification of illegal polluters. They rely on information that has been provided on potential oil spills by responsible institution. The first information is usually provided by satellite remote sensing. The decisions about oil combating action is taken based not only on SAR imagery, but checking confirmation from aerial surveillance and using oil spill modeling, also. SAR imagery and aerial surveillance does not provide information about the type of spilled oil, which is important input information for oil spill modeling. Different types of oil have different behavior in water and may affect the decisions about which oil combating activities should be taken. The aim of this study was to show how different type of oil behaves in water according to the Seatrack Web oil drift model, which is the main modeling tool of Estonian Border Guard who is responsible in oil combating. Current study is based on illegal oil spill accident that happened in the eastern Baltic Proper on 10 April 2010. Potential oil pollution was detected on SAR image at 9:08 UTC. Consecutive SAR image was obtained at 9:40 UTC showing no significant change of the slicks area and shape in such a short time. Oil pollution was also confirmed by aerial surveillance at 11:10 UTC. Report that was based on visual observations said that it was probably a bilge water, which started to vanish due to ship traffic. The pollution was also recorded by Side Looking Aperture Radar (SLAR). Seatrack Web model (STW) was used for the forecast of oil slick drift. The input of light and medium oil was chosen. The results showed rather different results about oil drift as well as about oil fate. In case of medium oil 20% of oil was expected to evaporate within a couple of hours and the rest stayed in water surface. In the case of light oil 20% was evaporated, but the rest of the oil was expected to disperse in to the water column and emerge on the surface in time to time. The light oil was simulated to drift to the NWW, while medium oil to the SW. Laboratory analyses of the sample that was taken at 14:30 UTC showed that heavy fraction of the oil (hydrocarbons C16-C36) was maintained in the water until then. In conclusion, this study shows that the information about the type of spilled oil is needed as soon as possible after the oil detection to make appropriate decision on oil combating activities.","PeriodicalId":287473,"journal":{"name":"2010 IEEE/OES Baltic International Symposium (BALTIC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130467522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dominant zoobenthic species in the northwestern coastal sea of Estonia — potential role of abiotic stresses","authors":"N. Kolesova, U. Raudsepp, V. Alari","doi":"10.1109/BALTIC.2010.5621647","DOIUrl":"https://doi.org/10.1109/BALTIC.2010.5621647","url":null,"abstract":"Most of the Estonian coastal sea in the western part of the Gulf of Finland is characterized by numerous small bays. Some of them are open to the waves and water exchange with the open sea area, while others are exposed to waves from only one direction and have therefore limited water exchange. The coastal sea in the northeastern Baltic Proper is more open to wave and current activity. The bottom material of the coastal sea varies widely from mud and sand to gravel and rocks. Besides, salinity decreases if to move from the northeastern region towards the central Gulf of Finland. These abiotic factors could affect the large-scale spatial distribution of zoobenthic species. The zoobenthos samples were collected during August-November 2007–2009 in 13 locations in the Estonian coastal sea in the area extending from Muuga Bay (the central Gulf of Finland) to Sõrve Peninsula (the northeastern Baltic Proper). Up to 18 triplicate samples were taken within one area. All samples were taken using Van Veen grab with the opening area of 0.025 m2 then sieved through 1.00 mm mesh sieve and preserved in a freezer. Bottom macrofauna was identified to the species level where practicable; such groups as crustaceans and oligochaets were identified to an appropriate higher taxonomic layer. Biomass was determined as wet weight (gww/m2). The average density and biomass of species was determined in each area separately to ascertain dominants. Species abundance and biomass varied considerably within one sampling area. Still we were able to determine dominant species in these areas. Both biomass and abundance showed that two major species Macoma balthica and Mytilus trossulus prevailed. Mytilus trossulus dominated in the open bays at the northeastern Baltic Proper and western Gulf of Finland. Macoma balthica was abundant and showed high biomass in the large bays of the central Gulf of Finland. The analyses confirmed that Mytilus trossulus preferred hard bottoms. Considering natural and anthropogenic stresses to dominant species, this study shows that the presence of harbors and frequent harbor development favors the dominance of Macoma balthica. Mytilus trossulus prevails in the areas that are more exposed to waves as shown by numerical experiments with the wave model SWAN.","PeriodicalId":287473,"journal":{"name":"2010 IEEE/OES Baltic International Symposium (BALTIC)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131298467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of operational ice charts with satellite based ice concentration products in the Baltic Sea","authors":"R. Uiboupin, L. Axell, U. Raudsepp, L. Sipelgas","doi":"10.1109/BALTIC.2010.5621649","DOIUrl":"https://doi.org/10.1109/BALTIC.2010.5621649","url":null,"abstract":"Satellite remote sensing data is used for operational monitoring of sea ice parameters in many countries locating on high latitude. The routinely monitored regions are interesting from the economical as well as from safe navigation point of view and include Baltic Sea, coastal waters of Canada (Hudson Bay, Canadian Arctic region, Great Lakes), Barents Sea, Kara Sea etc. The operational ice services in Sweden and Finland have been using a system called IceMap for many years. In this paper we will assess the possibility of using automatically processed satellite data for ice concentration estimation. The investigated satellite products include SIC from (1) Ocean & Sea Ice Satellite Application Facility (OSI SAF), (2) Advanced Microwave Scanning Radiometer for EOS (AMSR-E), and (3) Moderate Resolution Imaging Spectroradiometer (MODIS). The work aims at investigating whether one of these, or perhaps a combination of several, may be used operationally as an alternative or as a complimentary data to the IceMap system. This will be accomplished by objectively comparing the ice charts from the satellite products with the IceMap ice charts produced operationally by the Swedish Ice Service at the Swedish Meteorological and Hydrological Institute (SMHI). Visual comparison and correlation analysis will be carried out between the different products and the advantages and disadvantages of each product are discussed in the paper.","PeriodicalId":287473,"journal":{"name":"2010 IEEE/OES Baltic International Symposium (BALTIC)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123064142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-resolution monitoring of environmental state variables in the surface layer of the Gulf of Finland (during a dynamic spring bloom in March-May 2010)","authors":"V. Kikas, Nelli Norit, Aet Meerits, N. Kuvaldina, I. Lips, U. Lips","doi":"10.1109/BALTIC.2010.5621627","DOIUrl":"https://doi.org/10.1109/BALTIC.2010.5621627","url":null,"abstract":"The flow-through system (Ferrybox) installed onboard a ferry cruising between Tallinn and Helsinki in the Gulf of Finland (Baltic Sea) measures temperature, salinity, chlorophyll a fluorescence, turbidity and since January 2010 also pCO2. In March-May 2010, the water sampling was conducted on a weekly basis at 17 locations along the ferry route to measure nutrient concentrations (NO2+NO3 and PO4), chlorophyll a content and phytoplankton species composition and biomass. Our aim was to show that the Ferrybox technology can be successfully applied to follow the rapid changes of state variables during a very dynamic season of the year — phytoplankton spring bloom. High variability of environmental parameters has been observed both in space and time in the Gulf of Finland in spring 2010. It is suggested that both the general circulation in the surface layer and mesoscale hydrodynamic processes are influencing the bloom evolution and spatio-temporal variability. The observed coincidence of Chl a peaks with the periods of relatively fast temperature increase indirectly shows the importance of positive buoyancy fluxes (vertical stratification) for phytoplankton growth in spring. Spatio-temporal distribution of pCO2 was in a good accordance with the Chl a dynamics confirming that the pCO2 measurements can be used for the estimates of phytoplankton productivity. Our data confirm that the regular late evening fluorescence measurements can be successfully applied to determine the Chl a content in the surface waters in spring. It is concluded that autonomous high-resolution in-situ monitoring in combination with adaptive water sampling and remote sensing could give a full enough data set to assess the environmental state of the Gulf of Finland during this highly dynamic season of the year.","PeriodicalId":287473,"journal":{"name":"2010 IEEE/OES Baltic International Symposium (BALTIC)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115879322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advancing coastal upwelling observations with use of SAR data: Case study from SE Baltic","authors":"I. Kozlov, I. Dailidienė, V. Kudryavtsev","doi":"10.1109/BALTIC.2010.5621631","DOIUrl":"https://doi.org/10.1109/BALTIC.2010.5621631","url":null,"abstract":"Nowadays exploitation of satellite data, mostly infrared and visible, became a regular practice for upwelling detection and analysis. At the same time these types of satellite data strongly depend on sun illumination conditions and cloud cover, with the latter being very limiting factor specifically for the Baltic Sea. In this case SAR (Synthetic Aperture Radar) imagery not affected by clouds and with high spatial resolution can significantly contribute to upwelling observations. The aims of this study are to show how SAR complements both in situ and satellite optical data, and to examine general SAR limitations to observe sea surface temperature (SST) fronts associated with coastal upwelling.","PeriodicalId":287473,"journal":{"name":"2010 IEEE/OES Baltic International Symposium (BALTIC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131571060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Smart management of the Baltic Sea fishery system: Myth or reality?","authors":"R. Aps, M. Fetissov, H. Lassen","doi":"10.1109/BALTIC.2010.5621645","DOIUrl":"https://doi.org/10.1109/BALTIC.2010.5621645","url":null,"abstract":"System is smart if its negative feedback loop is constantly working to reduce the difference between the actual and desired states (goals) of the system. Goals itself should be SMART — specific, measurable, agreed upon, realistic and time-based. A precondition for smart management is the availability of a negative feedback loop based regulatory measure that can move the system towards desired state. Fishing fleet overcapacity and the associated low economic resilience impose a high political pressure to increase short-term fishing opportunities at the expense of the future sustainability of the industry. This pressure is leading to overfishing and it is hampering the efficiency of the system's negative feedback process. However, it is believed that introducing the Individual Transferable Quotas (ITQ) system as a basis for the Baltic Sea fisheries management would contribute into achieving both the Maximum Sustainable Yield (MSY) and the Maximum Economic Yield (MEY) objectives through the actual removal of excess fishing capacity. It is believed also that the ITQ system would create and enforce the missing negative feedback loop that will be constantly pushing the fishery system towards higher economic efficiency and ecological sustainability. In addition, wider implementation of the Marine Stewardship Council's (MSC) environmental standard for sustainable fishing could be seen as an important step towards smart fishery management system. MSC certification could enforce the market/consumer pressure for matching the fishing capacity and available fishery resources. Move towards smarter fishery management would contribute also to the success of emerging Marine Spatial Planning activities and to development of the climate change related special adaptation strategies.","PeriodicalId":287473,"journal":{"name":"2010 IEEE/OES Baltic International Symposium (BALTIC)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130900473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of lightweight on-line GPS drifters for surface current and ice drift observations","authors":"T. Kõuts, Svetlana Verjovkina, P. Lagemaa, U. Raudsepp","doi":"10.1109/BALTIC.2010.5621635","DOIUrl":"https://doi.org/10.1109/BALTIC.2010.5621635","url":null,"abstract":"A family of lightweight (less than 15 kg), long-life (up to 3–4 months) and low-cost drifters are developed in the Tallinn University of Technology and local engineering companies. Such buoys have a rugged and simple housing construction with the diameter of 11 cm and length of 1 m. The buoys are equipped with GPRS based two-way communication and they are programmable during the mission. The data are transferred in real time into one or several FTPs for the operational use in circulation and ice models for data assimilation and/or model validations. The buoys are used also for the estimation of oil drift and ice dynamics properties, e.g. ice drift, compacting, ridging, etc. Real-time (on-line) data transfer is performed via the GPRS protocol with a typical time interval of 15 minutes, but it can be programmed otherwise. The data received in FTP are ready to be used for model assimilation and in different operational applications and services like the drift of surface objects, ice and oil drift. It is possible to view the buoy data in real time via a special web solution. Two major measurement campaigns have been performed using light drifters. Firstly, the validation of High Resolution Operational Model for the Baltic Sea (HIROMB) surface currents in Estonian coastal waters in 2007 and secondly, the study of dynamic ice drift. In both cases the light on-line drifters showed good performance and stability for long-life operation. The percentage of fault positioning was higher in water, reaching up to 20%, and was mainly caused by the reflections of GPS signal from the waves, since a very small part of the buoy remains above the sea surface. In ice the fault positioning was lower, less than 10%. In the case of an ice covered sea, the buoys were from time to time pushed under ice for some period during which the positioning systems failed to transfer the signal. In 2007 during the period from August till November 17 experiments were carried out with surface drifters released in small coastal bays and the open sea of the Gulf of Finland. The longest period when a buoy was drifting lasted for 8 days. It moved across the Gulf of Finland covering a little less than 50 miles. In accordance with the drifter experiments the drifter trajectories that imitate oil spill drift were calculated from HIROMB currents and wind. The calculations were carried out with a different wind factor between 0–3%. The results of modeling showed close agreement with drifter data in some cases, but no unique wind factor suitable for the Gulf of Finland could be identified. In March-April 2010, an extensive ice drifter experiment was conducted in the eastern part of the Gulf of Finland. The development of light on-line GPS drifters continues. The platform of data logging and transfer allows adding a number of parameters to be measured by the drifter and transmitted on-line. To begin with, water temperature and salinity sensors will be added.","PeriodicalId":287473,"journal":{"name":"2010 IEEE/OES Baltic International Symposium (BALTIC)","volume":"106 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132708041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation of Seatrack Web using surface drifters in the Gulf of Finland and Baltic proper","authors":"Svetlana Verjovkina, U. Raudsepp, T. Kõuts, K. Vahter","doi":"10.1109/BALTIC.2010.5621634","DOIUrl":"https://doi.org/10.1109/BALTIC.2010.5621634","url":null,"abstract":"Seatrack Web (STW) is a numerical model for oil spill drift forecasting widely used by oil spill combating authorities around the Baltic Sea. Seatrack Web gives an opportunity to simulate oil slick trajectory 5 days ahead and 30 days back in time with 1 hour interval. It is possible to choose different substances, such as oil, chemicals or floating object. An option to use satellite detected oil spills is implemented in the model. For modeling of oil slick trajectory with STW forcing fields are needed. Wind and current are taken from High Resolution Operation Model for the Baltic (HIROMB). Currents and wind are used with 3 hour interval. The horizontal resolution of current velocities is 3 nautical miles. Vertical resolution of HIROMB model is 50 different depth layers. Seatrack Web uses the wind forecasts from 10 meters height. Lightweight, long-life and low-cost drifters are developed by Tallinn University of Technology and local engineering companies in Estonia. The drifters have rugged and simple housing construction and are equipped with GPRS based two-way communication. Drifters are constructed so that about 95% of it's cylinder like body is below waterline and during drifting the buoy shows that way well surface current. In operation, data are transferred and visualized in real time through special web based software. In this study, the drifters are used for the validation of Seatrack Web. The drifters were used in 13 cases being deployed in variety of locations. The experiments have different duration ranging from 8 hours up to 8 days. The longest distance covered during single experiment was 52 nautical miles. The simulations with Seatrack Web were performed using fresh oil and floating objects with different extra wind factors, as it was not clear how well the drifters respond to the direct wind drift. Besides, two drifters were released at the same location to study the spatial spreading. There was insignificant difference when fresh oil or floating object with 0 extra wind factors has been used in STW. In certain cases adding of extra wind factor improved the comparison between STW and drifter's trajectory. The best coincidence between STW and surface drifters gave average departure about 40 m/h. In general the departure was slightly in excess of 100 m/h. Thus, the analyses show that drifters of suggested construction can be used for monitoring of the pollution drift on the sea surface.","PeriodicalId":287473,"journal":{"name":"2010 IEEE/OES Baltic International Symposium (BALTIC)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114407356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Leads as natural fairways in the Gulf of Finland","authors":"O. Parn, J. Haapala, L. Sipelgas","doi":"10.1109/BALTIC.2010.5621638","DOIUrl":"https://doi.org/10.1109/BALTIC.2010.5621638","url":null,"abstract":"The monitoring and prediction of sea ice conditions are vital for safe and economical winter navigation in the Gulf of Finland (GoF), where ice conditions are very variable and dynamic. Flaw leads and ice ridges are common features in the GoF. In this study the occurrence frequency of the leads and ridges during 1971–2009 is analyzed. For the historical period, the ice charts of the Estonian Meteorological and Hydrological Institute (EMHI) were used for determining their occurrence and location in the Gulf of Finland. A case study was performed for a severe winter in 2002/2003. MODIS satellite imagery was used in addition to ice charts for determining the location of the leads in the Gulf of Finland. Also, the HELMI ice model was used to examine ice characteristics during the winter of 2002/2003 and the relationship between deformed ice growth rates and the speed and direction of wind. The results of the analysis of historical data show that on the average the leads are most common in the Estonian coastal region where their occurrence is typically 10–30%. During severe winters, leads occur quite often also in the Finnish coastal region, but the ridges are more common in the Estonian coast.","PeriodicalId":287473,"journal":{"name":"2010 IEEE/OES Baltic International Symposium (BALTIC)","volume":"12 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121180799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of microstructure measurements meeting the Baltic Sea conditions","authors":"A. Ostrovskii, V. Paka, S. Shchuka, A. Zatsepin, V. Zhmur, V. Baranov, A. Korzh, A. Kondrashov, A. P. Podufalov, D. Shvoev, V. Soloviev","doi":"10.1109/BALTIC.2010.5621642","DOIUrl":"https://doi.org/10.1109/BALTIC.2010.5621642","url":null,"abstract":"The principal physical research tasks addressing environmental problems of the Baltic Sea are the study of ventilation of the deep water and of vertical mixing. To achieve a progress, direct measurements of fine- and microstructure of water are necessary. Instrumentation to do this has been developed successfully; nevertheless the water structure in the Baltic Sea is so tricky that existing techniques need special adaptation and improvement. This paper presents several types of profilers: cycling profilers both towed and moored, and freely sinking or floating probes. Some of them perform direct microstructure measurements while others are necessary to obtain a properly resolved background measurement of thermohaline and current structure. We consider freely-moving CTDs as an alternative for direct dissipation measuring meters if the probe's motion is stable enough and its spatial resolution is high enough. Having in mind the Baltic conditions, special attention is paid to fine measurements close to the sea surface and within the bottom boundary layer. We try to adjust such instruments for use from small inexpensive boats, so we hope fine- and microstructure measurements will be more accessible.","PeriodicalId":287473,"journal":{"name":"2010 IEEE/OES Baltic International Symposium (BALTIC)","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124226136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}