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G.A. de Leeuw

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Measuring Unloading Performance Using Open Data

Master thesis (2025) - G.A. de Leeuw, M.B. Duinkerken, D.L. Schott, Reinier Tans
This study demonstrates that unloading performance at dry bulk terminals can be effectively assessed using open data sources such as AIS and aerial imagery. By structuring terminal operations into measurable performance indicators and applying the Overall Equipment Effectiveness (OEE) framework, we show that productivity, utilization, and occupancy can be quantified and benchmarked across terminals. The method is validated using data from two dry bulk terminals, revealing consistent patterns and highlighting operational differences. This approach enables scalable, low-cost performance analysis without requiring direct access to proprietary terminal data. ...
Journal article (2018) - Emmanouil Proestakis, Vassilis Amiridis, Vasiliki Daskalopoulou, Konstantinos A. Kourtidis, Gerrit De Leeuw, Ronald Johannes Van Der A, Eleni Marinou, Aristeidis K. Georgoulias, Stavros Solomos, Stelios Kazadzis, Julien Chimot, Huizheng Che, Georgia Alexandri, Ioannis Binietoglou
We present a 3-D climatology of the desert dust distribution over South and East Asia derived using CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) data. To distinguish desert dust from total aerosol load we apply a methodology developed in the framework of EARLINET (European Aerosol Research Lidar Network). The method involves the use of the particle linear depolarization ratio and updated lidar ratio values suitable for Asian dust, applied to multiyear CALIPSO observations (January 2007-December 2015). The resulting dust product provides information on the horizontal and vertical distribution of dust aerosols over South and East Asia along with the seasonal transition of dust transport pathways. Persistent high D-AOD (dust aerosol optical depth) values at 532 nm, of the order of 0.6, are present over the arid and semi-arid desert regions. Dust aerosol transport (range, height and intensity) is subject to high seasonality, with the highest values observed during spring for northern China (Taklimakan and Gobi deserts) and during summer over the Indian subcontinent (Thar Desert). Additionally, we decompose the CALIPSO AOD (aerosol optical depth) into dust and non-dust aerosol components to reveal the nondust AOD over the highly industrialized and densely populated regions of South and East Asia, where the non-dust aerosols yield AOD values of the order of 0.5. Furthermore, the CALIPSO-based short-term AOD and D-AOD time series and trends between January 2007 and December 2015 are calculated over South and East Asia and over selected subregions. Positive trends are observed over northwest and east China and the Indian subcontinent, whereas over southeast China trends are mostly negative. The calculated AOD trends agree well with the trends derived from Aqua MODIS (Moderate Resolution Imaging Spectroradiometer), although significant differences are observed over specific regions. ...