Dynaamisen kyydinjakosovelluksen reitinhakualgoritmin kehitt äminen

Vedia Taxi is a mobile application that makes it possible to share taxi rides with people going to the same direction. It uses an algorithm to combine the routes of different people to achieve this. However the algorithm can only handle cases where people leave from the same location and people cannot join from the route. The purpose of this work is to extend the algorithm to handle these cases. For the extended algorithm four routing services were compared. These routing services provide the raw route data and time estimates for the routes. Google Maps was chosen among these providers, because it had the most accurate time estimates for the routes. The raw routes from different providers had some differences, but all of them were adequate. While the Google Maps did not have the best route calculation time, it was crucial for the algorithm that the time estimates are as correct as they can be. The extended algorithm was tested using test searches that mimicked real life taxi rides, as there was not enough test data from real life rides made with the application. The performance of the algorithm was tested by using the same test searches. The test searches showcased that with the extended algorithm routes can be formed also when start locations are different. This also makes it possible to join along the route. The performance of the algorithm was highly dependant on the amount of time it took to calculate the raw routes. The calculation of routes took 92% and 98% of the running time of the algorithm. The average time to calculate raw route was 275ms and the evaluation of a single ride took 275-300ms.Vedia Taxi on mobiilisovellus, joka mahdollistaa taksikyytien jakamisen samaan suuntaan matkustavien ihmisten kesken. Jakamisen mahdollistaa algoritmi, joka yhdistelee eri ihmisten reittejä. Algoritmi pystyy kuitenkin yhdistämään vain reittejä, joissa kaikki ihmiset lähtevät samasta lähtöpisteestä. Ihmiset eivät myöskään voi liittyä kyytiin matkan varrelta. Työn tarkoituksena on jatkokehittää algoritmia niin, että kyytiin olisi mahdollista liittyä mistä tahansa. Uutta algoritmia varten vertailtiin neljää reitityspalvelua keskenään. Nämä reitityspalvelut tuottavat reittiohjeet ja aika-arviot reiteille. Google Maps valittiin parhaaksi reitityspalveluksi, koska sen aika-arviot reiteille olivat tarkimmat. Reittiohjeissa oli joitakin eroja eri reitityspalveluiden välillä, mutta kaikki niistä olivat tarpeeksi hyviä. Google Maps ei muodostanut reittejä kaikista nopeimmin, mutta algoritmin kannalta oli välttämätöntä, että aika-arviot olisivat mahdollisimman tarkkoja. Algoritmia testattiin käyttämällä kyytejä ja hakuja, jotka vastasivat todellisia taksikyytejä. Tämä lähestymistapa otettiin sen takia, että Vedia Taxi ei ollut tuottanut tarpeeksi oikeaa testimateriaalia. Algoritmin tehokkuutta mitattiin samoilla testikyydeillä ja -hauilla. Testihaut näyttivät, että uusi algoritmi pystyy yhdistämään reittejä niin, että ihmiset lähtevät eri aloituspisteistä. Uusi algoritmi mahdollisti myös sen, että ihmiset pystyvät liittymään kyytiin matkan varrelta. Algoritmin tehokkuus oli suuresti riippuvainen siitä, kuinka pitkä aika kului reittiohjeiden laskemiseen. Reittiohjeiden laskeminen kulutti 92%-98% algoritmin kokonaissuoritusajasta. Reittiohjeiden haku kesti keskimäärin 275ms ja yhden kyydin arviointi hakua vastaan kesti 275-300ms

Ant-associated beetles of Fennoscandia and Denmark

Ants have a negative impact on populations of many arthropod species. On the other hand, numerous arthropod species live in association with ants. In this paper we list ant-associated beetles (including myrmecophiles) of Fennoscandia and Denmark. Data is based on a literature survey and new field observations. We list 369 ant-associated beetle species of which 73 are categorized as myrmecophilous. Our data suggests that there might be numerous beetle species associated with ants, which are not generally known to do so. This indicates that ant colonies may be important habitats for a large variety of beetle species

Framework for assessing and reversing ecosystem degradation – Report of the Finnish restoration prioritization working group on the options and costs of meeting the Aichi biodiversity target of restoring at least 15 percent of degraded ecosystems in Finland

This report is an abridged and revised English language edition of the original proposition of the Finnish restoration prioritization working group on the options and costs of restoring 15 percent of degraded ecosystems in Finland. We start with the key findings and the original propositions of the working group. Based on the experiences from Finland, we also provide a few new propositions for the international readership to help to plan and implement work towards meeting the global target of restoring 15 percent of the degraded ecosystems. In the beginning of the report, we describe the conceptual background of the work, i.e. that ecosystem degradation or improvement has a minimum of two components: the extent of area that has become degraded or restored and the magnitude of the degradation, or its counterpart improvement, at any given location. We then describe the procedure that we developed to systematically measure the magnitude of degradation from which the 15 percent can be calculated and the magnitude of improvement that different restoration measures can offer. The guiding principle adopted for the development of the procedure was to treat all ecosystems that are not in their natural state as degraded. However, it is worth emphasizing that the objective is not to reach the natural state of the ecosystems, but to reduce the degree of ecosystem degradation by restoration. With an example from herb-rich forests, we show how we prioritized restoration measures within an ecosystem. The prioritization was based on the effects of restoration measures on biodiversity and on the costs of the measures. We also considered the effect of restoration measures on some key ecosystem services. In addition to the restoration measures within each ecosystem, we also conducted prioritization among ecosystems. The prioritization among ecosystems is based on an analysis identifying the ecosystems where reasonable investments bring the greatest reduction in the degree of ecosystem degradation. The procedure thus enabled us to find the balanced and cost-effective restoration measure portfolios within each ecosystem type and to allocate resources effectively to those ecosystem types that provided highest benefits in terms of biodiversity and reduction of the degree of ecosystem degradation. To our knowledge, this report is the first to estimate the cost of meeting the 15 percent restoration target across all relevant terrestrial ecosystems in one country. Our work exemplifies that simultaneous prioritization among all major terrestrial ecosystems greatly reduces the overall cost of meeting the 15 percent restoration target. Indeed, if we focus on restoring 15 per cent of one ecosystem type at a time, which is the modus operandi in many parts of the world, the overall cost of meeting the 15 percent restoration target is more than twice compared to the prioritization approach we have adopted here. Rather than getting fixed on the 15 percent target, we also decided to provide additional options for decision makers. Thus, the report gives alternative answers to the question of which ecosystem restoration measures to take, at which scale and in which ecosystem types, in order to meet the overall target for ecosystem restoration in Finland

Distribution, abundance and species richness of butterflies and myrmecophilous beetles

Suppealla alueella esiintyvät päiväperhoslajit ovat usein paikallisesti suhteellisen runsaslukuisia. Tämän yllättävän seikan havaitsi filosofian maisteri Jussi Päivinen tutkiessaan väitöskirjaansa varten päiväperhosia. Havainto on maailmanlaajuisesti erittäin harvinainen. Yhtenä syynä voi olla Suomen pohjoinen sijainti, jonka seurauksena monien päiväperhoslajien levinneisyysalue rajoittuu Etelä-Suomeen. - Levinneisyysalueensa reunalla elävät perhoslajit pystyvät asuttamaan ainoastaan suurimmat ja laadultaan parhaimmat elinympäristölaikut, mutta koska laikut ovat korkealaatuisia, niihin voi muodostua erittäin runsaslukuiset päiväperhoskannat. Reuna-alueella elävien päiväperhosten ns. elinympäristölaikut ovat todennäköisesti eristyneempiä kuin niiden lajien, joiden levinneisyysalue kattaa suuren osan tutkittavasta alueesta, Päivinen selvittää.Several mechanisms have been proposed to explain the patterns of species richness, distribution and abundance. Also several mechanisms have been put forward in explaining the generally observed positive relationship between regional distribution and local abundance of species. In this thesis factors affecting distribution, abundance and species richness were studied using butterflies and myrmecophilous beetles as study objects. The data of myrmecophilous beetles are based on the literature and a field survey and data of butterflies is based on the literature. This thesis suggests that ant colonies maintain species rich beetle fauna, and that widespread host ant species and the species with large colony size are able to maintain higher species richness of myrmecophilous beetles. Surprisingly, a strong negative relationship between local abundance and regional distribution was found for the Finnish butterflies. The study suggested that sedentary butterfly species, species at the edge of their distribution range and the most specialized species were locally abundant with restricted distribution. Mobile species, species furthest from the edge of their distribution and generalist butterfly species were locally few in number and widespread, thus, generating the negative relationship. Larval specificity, habitat breadth and resource availability were observed to be in a key role when explaining the mobility of the butterflies. Range position had strong effect both on the mobility and on the length of the flight period of the butterflies. The surprising results emphasize the importance of the study of basic ecology of species. More studies are needed to find out, whether observed negative relationship between distribution and abundance is a more general phenomenon than previously thought

Ennallistettujen soiden päiväperhosseurantaverkosto

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Varying definitions of abundance and incomplete assemblages challenge the generality of the interspecific abundance-distribution relationships

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