In the past 10 years, the collaborative maps of OpenStreetMap (OSM) have been used to support humanitarian efforts around the world as well as to fill important data gaps for implementing major ...development frameworks such as the Sustainable Development Goals. This paper provides a comprehensive assessment of the evolution of humanitarian mapping within the OSM community, seeking to understand the spatial and temporal footprint of these large-scale mapping efforts. The spatio-temporal statistical analysis of OSM's full history since 2008 showed that humanitarian mapping efforts added 60.5 million buildings and 4.5 million roads to the map. Overall, mapping in OSM was strongly biased towards regions with very high Human Development Index. However, humanitarian mapping efforts had a different footprint, predominantly focused on regions with medium and low human development. Despite these efforts, regions with low and medium human development only accounted for 28% of the buildings and 16% of the roads mapped in OSM although they were home to 46% of the global population. Our results highlight the formidable impact of humanitarian mapping efforts such as post-disaster mapping campaigns to improve the spatial coverage of existing open geographic data and maps, but they also reveal the need to address the remaining stark data inequalities, which vary significantly across countries. We conclude with three recommendations directed at the humanitarian mapping community: (1) Improve methods to monitor mapping activity and identify where mapping is needed. (2) Rethink the design of projects which include humanitarian data generation to avoid non-sustainable outcomes. (3) Remove structural barriers to empower local communities and develop capacity.
Lakes are sensitive indicators of anthropogenic climate change and also respond to direct human activities. Yet, long-term lake inventories and quantitative evaluation of the factors driving observed ...lake changes across China remain elusive. Here, for the first time, we examined multi-decadal lake area changes in China during 1960s–2015, using historical topographic maps and >3831 Landsat satellite images, including lakes as fine as ≥1 km2 in size. In addition, we quantified the causes of lake changes from climatic and anthropogenic factors. The total area of lakes in China has increased by 5858.06 km2 (9%) between 1960s and 2015, and with heterogeneous spatial variations. Lake area changes in the Tibetan Plateau, Xinjiang, and Northeast Plain and Mountain regions reveal significant increases of 5676.75, 1417.15, 1134.87 km2 (≥15%), respectively, but the Inner-Mongolian Plateau shows an obvious decrease of 1223.76 km2 (22%). We find that 141 new lakes have appeared predominantly in the arid western China; but 333 lakes, mainly located in the humid eastern China, have disappeared over the past five decades. We conclude that climate factors have played a dominant role in lake changes across China, coupled with noticeable anthropogenic contribution of ~35% in the Eastern Plain and Yunnan-Guizhou Plateau. This study has substantial implications to improve decision support regarding water-resource management strategies and land-use planning throughout China.
•Produced a comprehensive China lake dataset from the 1960s to 2015•Total lake area increased by 9% over five decades with evident regional differences•New lakes and lake area expansion in the arid western China due to climate change•Disappeared and shrinking lakes in the humid eastern China due to human activity
•Clustering of passenger cards using continuous temporal activities.•The replicability of the approach proposed by Briand et al. (2016) is demonstrated.•Offering a simple interpretation of cluster ...patterns.•A longitudinal analysis is performed to study the evolution of passenger behaviour.•Spatial characterization is performed on the clusters using Shannon entropy.
In recent years, there has been increased interest in using completely anonymized data from smart card collection systems to better understand the behavioural habits of public transport passengers. Such an understanding can benefit urban transport planners as well as urban modelling by providing simulation models with realistic mobility patterns of transit networks. In particular, the study of temporal activities has elicited substantial interest. In this regard, a number of methods have been developed in the literature for this type of analysis, most using clustering approaches. This paper presents a two-level generative model that applies the Gaussian mixture model to regroup passengers based on their temporal habits in their public transportation usage. The strength of the proposed methodology is that it can model a continuous representation of time instead of having to employ discrete time bins. For each cluster, the approach provides typical temporal patterns that enable easy interpretation. The experiments are performed on five years of data collected by the Société de transport de l’Outaouais. The results demonstrate the efficiency of the proposed approach in identifying a reduced set of passenger clusters linked to their fare types. A five-year longitudinal analysis also shows the relative stability of public transport usage.
•Create a simple, easy of implement and accurate VMPP estimator.•Stability analysis of the proposed system based on the Lyapunov’s theory.•A comparative study versus P&O, highlight SMC good ...performances.•Construct a new PS-SMC algorithm to include the partial shadow case.•Experimental validation of the SMC MPP tracker.
This paper presents a photovoltaic (PV) system with a maximum power point tracking (MPPT) facility. The goal of this work is to maximize power extraction from the photovoltaic generator (PVG). This goal is achieved using a sliding mode controller (SMC) that drives a boost converter connected between the PVG and the load. The system is modeled and tested under MATLAB/SIMULINK environment. In simulation, the sliding mode controller offers fast and accurate convergence to the maximum power operating point that outperforms the well-known perturbation and observation method (P&O). The sliding mode controller performance is evaluated during steady-state, against load varying and panel partial shadow (PS) disturbances. To confirm the above conclusion, a practical implementation of the maximum power point tracker based sliding mode controller on a hardware setup is performed on a dSPACE real time digital control platform. The data acquisition and the control system are conducted all around dSPACE 1104 controller board and its RTI environment. The experimental results demonstrate the validity of the proposed control scheme over a stand-alone real photovoltaic system.
Cilj. Cilj je rada široj AKM zajednici predstaviti javno dostupne alate geokodiranja koji mogu biti korisni za predstavljanje raznolikih zbirki vezanih za pojedino područje. Rad će predstaviti neke ...od javno dostupnih alata te iznijeti njihove prednosti i nedostatke, mogućnosti primjene i pristupačnost. Pristup/metodologija/dizajn. Teorijski su razgraničeni osnovni pojmovi s kojima se autori virtualnih izložbi i interaktivnih karata susreću (GIS, mapiranje, geokodiranje, geolociranje). Uz pomoć analize koja razmatra prednosti, nedostatke, ustanove kojima je namijenjen te cijenu, napravljena je usporedba sedamnaest javno dostupnih alata za geokodiranje. Rezultati. Analizirano je 17 alata za geokodiranje. Od 17 promatranih alata, njih 10 ima širok spektar primjene koji, po mišljenju autora, uključuje i AKM zajednicu. Rezultati donose prednosti, nedostatke, cijenu i namjenu (odnosno korisnike) promatranih alata, a proučene su mogućnosti primjene, jednostavnost korisničkog sučelja, otvorenost koda, preglednost, trajnost pristupa i cjenovni rangovi. Ograničenja. Velik broj javno dostupnih alata za geokodiranje kao i njihov kontinuirani razvoj onemogućuju nam analizu svih. Također, usprkos podrobnom upoznavanju, svi analizirani alati za geokodiranje nisu korišteni od strane autora, samo pojedini, što ostavlja mogućnost da su se pojedine prednosti ili nedostaci previdjeli. Praktična primjena. U radu su predstavljeni javno dostupni alati za geokodiranja koji mogu biti korisni za promociju digitalnih zbirki na interaktivan i popularan način. Originalnost/vrijednost. Vrijednost ovoga rada ogleda se u činjenici da su na jednom mjestu obuhvaćeni i analizirani javno dostupni alati za geokodiranje koji mogu poslužiti ustanovama AKM zajednice za njihovu usporedbu prije odlučivanja o odabiru alata za izradu interaktivne karte na temelju vlastitih digitalnih zbirki.
This volume argues that the mapping of stories, movement and change should not be understood as an innovation of contemporary cartography, but rather as an important aspect of human cartography with ...a longer history than might be assumed. The authors in this collection reflect upon the main characteristics and evolutions of story and motion mapping, from the figurative news and history maps that were mass-produced in early modern Europe, through the nineteenth- and twentieth-century flow maps that appeared in various atlases, up to the digital and interactive motion and personalised maps that are created today. Rather than presenting a clear and homogeneous history from the past up until the present, this book offers a toolbox for understanding and interpreting the complex interplays and links between narrative, motion and maps.
•Passenger waiting times are modelled as a uniform and beta mixture distribution.•Validated framework that can improve waiting time estimations in transport models.•Results show that many passengers ...arrive in a timely manner to stations even at short headways.•Results highlight the importance of published timetables.
Waiting time at public transport stops is perceived by passengers to be more onerous than in-vehicle time, hence it strongly influences the attractiveness and use of public transport. Transport models traditionally assume that average waiting times are half the service headway by assuming random passenger arrivals. However, research agree that two distinct passenger behaviour types exist: one group arrives randomly, whereas another group actively tries to minimise their waiting time by arriving in a timely manner at the scheduled departure time. This study proposes a general framework for estimating passenger waiting times which incorporates the arrival patterns of these two groups explicitly, namely by using a mixture distribution consisting of a uniform and a beta distribution. The framework is empirically validated using a large-scale automatic fare collection system from the Greater Copenhagen Area covering metro, suburban, and regional rail stations thereby giving a range of service headways from 2 to 60 min. It was shown that the proposed mixture distribution is superior to other distributions proposed in the literature. This can improve waiting time estimations in public transport models. The results show that even at 5-min headways 43% of passengers arrive in a timely manner to stations when timetables are available. The results bear important policy implications in terms of providing actual timetables, even at high service frequencies, in order for passengers to be able to minimise their waiting times.
Rad se bavi slikom Europe zagrebačkih srednjoškolaca. Rezultati se temelje na anketnom istraživanju provedenom 2016. – 2017., koje je ponovilo istraživanje provedeno 2000. – 2001. (Šakaja, 2001; ...Šakaja i Mesarić, 2001; Šakaja, 2002). Ponavljanje istraživanja po istoj metodologiji i na sličnome uzorku omogućilo je longitudinalnu analizu predodžbe mladih Zagrepčana o Europi, odnosno europskim zemljama. U obradi podataka primijenjena je metodologija koju su predložili Peter Gould i Rodney White (1986). Rezultati su pokazali da je Europa na imaginativnoj karti obiju generacija mladih Zagrepčana jasno podijeljena na razvijeni Zapad i zaostali Istok. Obje su generacije percipirale Europu unutar binarnih opozicija. No znatan porast statusa Rusije upućuje na pomake unutar te binarnosti. Kvalitativna obrada odgovora na otvorena anketna pitanja pokazala je da nova generacija svoj izbor najpoželjnijih zemalja u najvećoj mjeri temelji na ekonomskim značajkama zemalja destinacije, za razliku od prijašnje generacije, koja je pri svojoj visokoj evaluaciji poželjnih zemalja nešto češće navodila kulturne razloge od ekonomskih. Sukladno tome u razmišljanju o migracijskim odredištima unutar Europe kriterij pripadnosti tradicionalnim, povijesno uspostavljenim europskim kulturnim krugovima manje je relevantan nego prije, što je vidljivo iz relativnoga pada statusa mediteranskih zemalja, posebno Italije, kao poželjnoga odredišta za migraciju. Nasuprot tome porastao je stupanj poželjnosti sjevernih, osobito skandinavskih, zemalja. Jedna od najvećih sličnosti u rezultatima iz 2000./2001. i 2016./2017. jest pozicioniranje balkanskih zemalja, osobito Albanije, Srbije i Kosova, na samo dno liste prostornih preferencija – kako zbog percipiranih slabih ekonomskih značajki tih zemalja tako i zbog izrazitih, očito stabilnih, negativnih stereotipa.
U radu se razmatraju mogućnosti prikaza pokreta primjenom statičnih tematskih karata na primjeru migracija – procesa koji čini dio svakodnevice, a koji može biti i prostorno i vremenski izrazito ...varijabilan. Migracije se u demografskoj literaturi, ali i šire, primjerice u dnevnome tisku, grafički najčešće prikazuju kartama toka. Karte toka zorno predočavaju „temu“ pokreta u prostoru, no migracije, odnosno odabrane sastavnice migracija, moguće je prikazati i uz pomoć drugih vrsta tematskih karata. Ono što pritom svakako predstavlja najveću poteškoću je prikaz vremena, odnosno istodobni prikaz više godina ili razdoblja na jednoj statičnoj tematskoj karti. U radu su prikazane mogućnosti prikaza sastavnica migracija primjenom više različitih vrsta statičnih tematskih karata, prednosti i nedostaci svake od njih, s posebnim osvrtom na mogućnosti i poteškoće zajedničkog prikaza prostorne i vremenske varijable migracija na karti.
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