Using a Generalisation Critic to find Bisimulations for Coinductive Proofs

Coinduction is a method of growing importance in reasoning about functional languages, due to the increasing prominence of lazy data structures. Through the use of bisimulations and proofs that bisimilarity is a congruence in various domains it can be used to prove the congruence of two processes. A coinductive proof requires a relation to be chosen which can be proved to be a bisimulation. We use proof planning to develop a heuristic method which automatically constucts a candidate relation. If this relation doesn't allow the proof to go through a proof critic analyses the reasons why it failed and modifies the relation accordingly. Several proof tools have been developed to aid coinductive proofs but all require user interaction. Crucially they require the user to supply an appropriate relation which the system can then prove to be a bisimulation.

Aplicação da metodologia numérica “fast bounds crack” para uma estimativa eficiente da evolução do tamanho de trinca

A significant part of the life of a mechanical component occurs, the crack propagation stage in fatigue. Currently, it is had several mathematical models to describe the crack growth behavior. These models are classified into two categories in terms of stress range amplitude: constant and variable. In general, these propagation models are formulated as an initial value problem, and from this, the evolution curve of the crack is obtained by applying a numerical method. This dissertation presented the application of the methodology "Fast Bounds Crack" for the establishment of upper and lower bounds functions for model evolution of crack size. The performance of this methodology was evaluated by the relative deviation and computational times, in relation to approximate numerical solutions obtained by the Runge-Kutta method of 4th explicit order (RK4). Has been reached a maximum relative deviation of 5.92% and the computational time was, for examples solved, 130,000 times more higher than achieved by the method RK4. Was performed yet an Engineering application in order to obtain an approximate numerical solution, from the arithmetic mean of the upper and lower bounds obtained in the methodology applied in this work, when you don’t know the law of evolution. The maximum relative error found in this application was 2.08% which proves the efficiency of the methodology "Fast Bounds Crack".

Analysis of N-nitrosames in water using micellar electrokinetic chromatography (MEKC) and development of online and offline methods of extraction and enrichment of neutral polar analytes

Evaluation of the quality of the environment is essential for human wellness as pollutants in trace amounts can cause serious health problem. Nitrosamines are a group of compounds that are considered potential carcinogens and can be found in drinking water (as disinfection byproducts), foods, beverages and cosmetics. To monitor the level of these compounds to minimize daily intakes, fast and reliable analytical techniques are required. As these compounds are relatively highly polar, extraction and enrichment from environmental samples (aqueous) are challenging. Also, the trend of analytical techniques toward the reduction of sample size and minimization of organic solvent use demands new methods of analysis. In light of fulfilling these requirements, a new method of online preconcentration tailored to an electrokinetic chromatography is introduced. In this method, electroosmotic flow (EOF) was suppressed to increase the interaction time between analyte and micellar phase, therefore the only force to mobilize the neutral analytes is the interaction of analyte with moving micelles. In absence of EOF, polarity of applied potential was switched (negative or positive) to force (anionic or cationic) micelles to move toward the detector. To avoid the excessive band broadening due to longer analysis time caused by slow moving micelles, auxiliary pressure was introduced to boost the micelle movement toward the detector using an in house designed and built apparatus. Applying the external auxiliary pressure significantly reduced the analysis times without compromising separation efficiency. Parameters, such as type of surfactants, composition of background electrolyte (BGE), type of capillary, matrix effect, organic modifiers, etc., were evaluated in optimization of the method. The enrichment factors for targeted analytes were impressive, particularly; cationic surfactants were shown to be suitable for analysis of nitrosamines due to their ability to act as hydrogen bond donors. Ammonium perfluorooctanoate (APFO) also showed remarkable results in term of peak shapes and number of theoretical plates. It was shown that the separation results were best when a high conductivity sample was paired with a BGE of lower conductivity. Using higher surfactant concentrations (up to 200 mM SDS) than usual (50 mM SDS) for micellar electrokinetic chromatography (MEKC) improved the sweeping. A new method for micro-extraction and enrichment of highly polar neutral analytes (N-Nitrosamines in particular) based on three-phase drop micro-extraction was introduced and its performance studied. In this method, a new device using some easy-to-find components was fabricated and its operation and application demonstrated. Compared to conventional extraction methods (liquid-liquid extraction), consumption of organic solvents and operation times were significantly lower.

Otimização de uma linha de aglomeração de materiais reciclados

Dado a globalização dos negócios e o aumento da competitividade dos produtos, é cada vez mais difícil para as grandes empresas manter a sua posição no mercado. Este processo quer-se rápido, eficaz e com o menor custo possível. Para este efeito, a metodologia Lean tem oferecido respostas bastante interessantes às empresas, com a aplicação de ferramentas da metodologia muito simples mas muito eficientes. Garantir características no produto final que façam á empresa manter ou ganhar cota no mercado é fundamental. Como tal, as empresas tentam ao máximo garantir a qualidade e o aspecto visual do produto. Posto isto, foram efetuados vários trabalhos para fazer frente às situações acima apresentadas e fazer com que o produto continue competitivo, para que possa aumentar a sua margem de lucro, mantendo o seu valor no mercado. Os trabalhos efetuados foram: plano de manutenção autónoma, um estudo do efeito da velocidade do misturador no produto final e um balanceamento à linha de aglomeração. Com a aplicação do Plano de Manutenção Autónoma, foi possível eliminar desperdícios, tornar a linha mais organizada e limpa e instruir os operadores a serem mais responsáveis, organizados e críticos ao seu trabalho. Quanto ao estudo do efeito da velocidade do misturador no produto final, os resultados não foram os esperados, dado que com o ensaio industrial efetuado não foi possível melhorar significativamente o aspeto visual do produto. Apesar de não ter sido possível a sua implementação, com o estudo do Balanceamento da linha, junto com os dados recolhidos foi possível obter um conhecimento mais pormenorizado da linha, foi criada uma possibilidade de proteger a linha de possíveis flutuações do mercado e eliminação de desperdício e uma possibilidade de listagem de tarefas estandartizadas e equilibradas, promovendo um menor esforço aos operadores. Em síntese, com a elaboração destes trabalhos, foi possível provocar um impacto positivo na linha, tornando-a mais organizada, reduzindo desperdício, protegendo de flutuações do mercado e aumentando o conhecimento da mesma.

Ceramic Materials Development for Intermediate Temperature Solid Oxide Fuel Cell (IT-SOFC)

Solid oxide fuel cell (SOFC) is an electrochemical device that converts chemical energy into electric power with high efficiency. Traditional SOFC has its disadvantages, such as redox cycling instability and carbon deposition while using hydrocarbon fuels. It is because traditional SOFC uses Ni-cermet as anode. In order to solve these problems, ceramic anode is a good candidate to replace Ni. However, the conductivity of most ceramic anode materials are much lower than Ni metal, and it introduces high ohmic resistance. How to increase the conductivity is a hot topic in this research field. Based on our proposed mechanism, several types of ceramic materials have been developed. Vanadium doped perovskite, Sr1-x/2VxTi1-xO3 (SVT) and Sr0.2Na0.8Nb1-xVxO3 (SNNV), achieved the conductivity as high as 300 S*cm-1 in hydrogen, without any high temperature reduction. GDC electrolyte supported cell was fabricated with Sr0.2Na0.8Nb0.9V0.1O3 and the performance was measured in hydrogen and methane respectively. Due to vanadium’s intrinsic problems, the anode supported cell is not easy. Fe doped double perovskite Sr2CoMoO6 (SFCM) was also developed. By carefully doping Fe, the conductivity was improved over one magnitude, without any vigorous reducing conditions. SFCM anode supported cell was successfully fabricated with GDC as the electrolyte. By impregnating Ni-GDC nano particles into the anode, the cell can be operated at lower temperatures while having higher performance than the traditional Ni-cermet cells. Meanwhile, this SFCM anode supported SOFC has long term stability in the reformate containing methane. During the anode development, cathode improvement caused by a thin Co-GDC layer was observed. By adding this Co-GDC layer between the electrolyte and the cathode, the interfacial resistance decreases due to fast oxygen ion transport. This mechanism was confirmed via isotope exchange. This Co-GDC layer works with multiple kinds of cathodes and the modified cell’s performance is 3 times as the traditional Ni-GDC cell. With this new method, lowering the SOFC operation temperature is feasible.

A essência da gastronomia na valorização cultural : a aplicação do conceito "Slow Food" nos Açores

Dissertação de Mestrado, Gestão do Turismo Internacional, 19 de Julho de 2016, Universidade dos Açores.

Avaliação de hábitos de consumo e adequação nutricional de refeições rápidas cuja base é o pão

As rápidas alterações sociais, económicas, culturais e ambientais determinaram mudanças significativas nos estilos de vida e contribuíram para o crescimento e generalização do consumo de alimentos e refeições fora de casa. Portugal acompanha a tendência de aumento do consumo alimentar fora de casa, assim, as refeições fora de casa, que há uns anos eram um acontecimento fortuito, são hoje uma prática habitual das famílias portuguesas, não só durante a semana de trabalho, mas também nos fins-de-semana. As, visitas aos centros comerciais que se tornaram um hábito no nosso país incluem uma paragem nas Praças de Alimentação, espaços de excelência pela diversidade alimentar onde predominam as refeições de fast-food. Porém é fundamental a escolha adequada/equilibrada dos alimentos que se vão consumir. O presente trabalho procurou avaliar os hábitos e percepção dos consumidores de refeições rápidas com base numa ementa específica cujo alimento principal é o pão. Posteriormente e de acordo com as preferências de consumo procedeu-se à avaliação nutricional das escolhas. Neste estudo participaram 150 indivíduos que frequentaram as instalações de um restaurante de comida rápida situada na praça de alimentação de um centro comercial situado em Viseu. Foi aplicado um questionário de autopreenchimento, por nós elaborado dividido em 4 partes: caracterização sociodemográfica; hábitos de consumo dos inquiridos; produtos escolhidos pelos inquiridos; grau de satisfação face aos produtos escolhidos. As análises estatísticas foram efectuadas com recurso ao Programa informático Statistical Package for the Social Sciences - SPSS® for Windows, versão 22. Realizam-se testes de Qui-quadrado com simulação de Monte Carlo, considerando o nível de significância de 0,05. Com base nas escolhas mais frequentes feitas pelos inquiridos procedeu-se à avaliação nutricional dos menus recorrendo ao programa DIAL 1.19 versão 1 e quando não se encontrou informação neste utilizou-se a tabela de composição de alimentos portugueses on line (INSA, 2010). Compararam-se os valores obtidos para o Valor Calórico Total, os macronutrientes, a fibra, o colesterol e o sódio com as Doses Diárias Recomendadas. A amostra era composta por 68,7% mulheres e 31,3% homens, com uma média de idades de 29,9 ± 3 anos e, maioritariamente empregados (64,7%). O grau de instrução da maioria dos inquiridos (54,7%) era o ensino superior. Grande parte da amostra não se considera consumidora habitual de fast-food,referindo ainda efectuar frequentemente uma alimentação equilibrada. Sendo que apenas 5 % frequenta as instalações mais de uma vez por semana. De entre os produtos disponíveis, a preferência fez-se pela sandes e batata-frita, sendo o momento de maior consumo o almoçoA avaliação nutricional das escolhas preferenciais dos inquiridos mostrou que o VCT do menu que inclui água como bebida está dentro dos limites calóricos preconizados para o almoço excepção feita ao menu que inclui sandes quente de frango em pão de orégãos e sandes fria de queijo fresco que se destacam por apresentar um valor inferior ao limite mínimo recomendado. Pelo contrário, a inclusão no menu do refrigerante faz com que haja um aumento do VCT, independentemente da sandes considerada, em 18%. Uma análise detalhada mostra que estas ementas são desequilibradas, apresentando 33,3% delas valores de proteínas superiores à DDR enquanto que os valores de HC e lípidos se encontram maioritariamente dentro dos limites havendo apenas 13,3% das ementas fora desses valores. Relativamente ao aporte de fibra e de sódio 86,7% das ementas aparecem desenquadradas com valores excessivos de sódio e valores de fibra 33% abaixo do limite mínimo recomendado. Tratando-se de um estudo de caso em que apenas se inclui um único restaurante de uma praça de alimentação, que fornece ementas à base de pão (sandes) os resultados são interpretados de forma cautelosa e sem generalização. Podemos no entanto concluir, face aos resultados obtidos a necessidade de redução do teor de sal das ementas. Para além disso parece-nos fundamental, para que o consumidor possa comparar opções alimentares e tomar decisões informadas, a disponibilização da informação nutricional das ementas propostas.

Supply Chain Adaptation of Finnish Companies in Chinese Institutional Environment

Within the last few decades of operations and supply chain management, the field has seen the rise of so called best practices, methods that will help supply chains obtain their business goals and gain a competitive edge. These methods were thought to be universal. This however is not always the case, as the surrounding business environment could have a significant impact on what will be effective in gaining competitive edge. Contingency theory states that the success of a supply chain is determined by both internal capabilities, as well as external context aligning. This creates a strategic fit, which is a major determinant of success. In order for supply chains to reach this strategic fit, they must adapt. As China has seen rapid growth and over the last few decades become one of the major economies of the world, Western companies have tried to establish themselves there, only to find that the Chinese market is extremely difficult to operate in. The aim of this thesis was to investigate from contingency theory perspective, what are the institutional factors that affect supply chain management of Finnish companies operating in China, and how do Finnish companies adapt their supply chains to better fit the Chinese institutional environment. A theoretical model was created for this thesis, in which supply chains possess resources, which can be combined in a meaningful manner to create capabilities. Both resources and capabilities are affected by the surrounding institutional environment, which forces supply chains to adapt in order to find a better strategic fit. A total of six Finnish managers from three large and three small companies operating in China were interviewed. The results indicated that the Chinese business environment is significantly different, than that of Finland or Western countries in general. Three institutional factors were identified: Confucian though, fast-paced business environment, and managing labor force. These three institutional factors made the relationship and delivery capabilities particularly important, as well as human resources, reputation, physical resources and technological resources. In conclusion, it was discovered that the Chinese institutional environment is heavily affected by Confucian thought, as well as the rapid market growth. These are the two most important institutional factors that shape the Chinese market. If supply chains wish to be successful in China, adaptation regarding these two institutional factors should yield good results.

Yhteistä turvallisuutta rakentaen : poliisi- ja upseeriprofessioiden yhteiskehittelyn mahdollisuuksista

Poliisin rakenneuudistus Pora III ja Puolustusvoimauudistus 2011–2015 ovat olleet viime vuosien esimerkkejä julkisen sektorin työn tehostamisen vaatimuksista. Sekä Puolustusvoimilla että poliisilla, kahdella turvallisuusalan viranomaistaholla, on lakisääteiset tehtävänsä, jotka tulee työn tehostamisen vaatimuksista huolimatta suorittaa. Turvallisuusala yksityistyy vauhdilla, ja keskustelua käydään siitä, mitä tehtäviä viranomainen hoitaa itse, mitä annetaan kaupallisen toimijan tai järjestöjen hoidettavaksi ja mistä kansalainen vastaa itse jatkossa. Resurssi- ja tehostamisvaatimuksia mietittäessä nousee esille upseereiden kohdalla koko maan puolustus ja turvaaminen. Kyetäänkö tämän tehtävän täyttämiseen mahdollisessa sotatilanteessa enää nykyisellä tai mahdollisesti vähenevällä resursoinnilla? Poliisitoimen osalta vasteajat eri puolilla Suomea puhuttavat, samoin se, miten tehtäviä priorisoidaan hoidettavaksi. Saavatko kansalaiset enää perusoikeuksiinsa kuuluvaa arjen turvallisuutta, jonka vielä tänä päivänä katsotaan kuuluvan valtion perustehtäviin? Viranomaisten pitäisi tutkimukseen valittujen aineistojen sekä lakien perusteella hoitaa tehtävänsä laadukkaasti ja tasa-arvoisesti kaikkialla Suomessa. Nykyiset sisäistä ja ulkoista turvallisuutta käsittelevät asiakirjat, esimerkiksi strategiat, puhuvat laajasta turvallisuuskäsityksestä, sisäisen ja ulkoisen turvallisuuden rajojen hämärtymisestä globalisoitumisen seurauksena ja lisääntyvästä poikkihallinnollisesta yhteistyöstä toimintaa ohjaavana ajattelumallina. Viranomaisyhteisyötä tulisi lisätä osana normaalia toimintaa, samoin yhteistyötä järjestöjen, elinkeinoelämän ja jokaisen kansalaisen kanssa. Valtioneuvoston tulevaisuusselonteossa (2013) peräänkuulutetaan uusia, innovatiivisia tapoja hoitaa sekä valtion että kuntien tehtäviä. Yhteisen toiminnan kohteen eli laajan turvallisuuskäsityksen viitekehyksessä on mahdollisuus pohtia uudenlaista turvallisuusalan viranomaisyhteistyötä, eli etsiä perusteluja upseeri- ja poliisiprofession syvemmälle yhteistyölle – yhteiskehittelylle. Tutkimukseni tavoitteena on herätellä keskustelua siitä, onko yhteisen toiminnan kohteen löytymiselle edellytyksiä. Nähtävissä on, että valtiolle kuuluvia toimintoja tehostetaan jatkossakin. Yksi järkevä tapa tehostamisessa on löytää töiden rajapintoja ja yhdistää resurssit näiden osalta. Jotta toiminta olisi tehokasta, sen pitää olla osa jokapäiväistä toimintaa eikä perustua vain muutamiin yhteistoimintaharjoituksiin tai jo tapahtuneiden poikkeustilanteiden hoitoon. Suurin osa kriisiajan toiminnasta perustuu normaaliolojen toimintaan, jolloin sen lähtökohdat voisivat olla yhteisessä työssä ja alkaa jo koulutuksesta, mikä nostetaan tässä työssä yhtenä mahdollisuutena esille. Koulutuksellinen yhteistyö ja liikkuvuus ovat eurooppalaisen tutkintojen viitekehyksen perusteella mahdollista myös kahden eri hallinnonalan koulutuksessa. Tällaista koulutuksen tehostamista haetaan tällä hetkellä muualla yhteiskunnassa. Mutta halutaanko omasta toiminnasta ja tehtävistä luopua edes osittain ja tehdä yhteistyötä mahdollisesti oman työn hallinnan, vallan tai resurssien menettämisen pelossa? Vai onko kyse vain siitä, että yhteistyön syventämiselle ei ole nähty kovinkaan suurta tarvetta tai hyötyä eikä yhteistyö näytä tuovan mitään uutta ammattikuntien osaamiseen? Tutkimuksen aineisto koostuu valtionhallinnon aineistoista, kuten strategioista, mietinnöistä ja raporteista niin sisäisen kuin ulkoisen turvallisuuden alalta. Aineistona käytetään myös upseeri- (n=71) ja poliisipäällystöopiskelijoille (n=65) suunnattua kyselyä ja kirjoitelmaa tulevaisuuden turvallisuusasiantuntijuudesta vuonna 2030. Lisäksi opiskelijavastauksista tehtyä analyysia syvennetään molempien korkeakoulujen (Maanpuolustuskorkeakoulu ja Poliisiammattikorkeakoulu) rehtoreiden sekä molempien hallinnonalojen (puolustusministeriö sekä sisäministeriö) kansliapäälliköiden haastatteluilla. Aineistojen avulla pyritään herättelemään ajatuksia siitä, voisiko yhteisiä töitä löytyä yhteistyön pohjaksi. Tarkoituksena on perustella, miksi yhteistyötä kannattaa tehdä ja ikään kuin vastata etukäteen vastaväitteisiin, miksi sitä ei voitaisi tehdä. Strategioiden yhteistyön tahtotilaa verrataan muihin strategioiden toimenpide ehdotuksiin ja sitä kautta vielä kyselyaineistoon. Opiskelijakyselyllä haetaan näkemyksiä tulevaisuuden turvallisuusasiantuntijuudesta ja mahdollisesta yhteistyöstä sekä sen painopisteistä. Muilla asiantuntijahaastatteluilla haetaan korkeakoulujen sekä ministeriön tason näkemyksiä opiskelijoiden mielipiteisiin. Opiskelijakyselyn avulla on haluttu selvittää sitä, mitä jo työelämässä olleet mutta vaihteeksi opiskelevat sotatieteiden maisteriopiskelijat Maanpuolustuskorkeakoulussa ja poliisin päällystötutkinnon opiskelijat Poliisiammattikorkeakoulussa ajattelevat turvallisuusalan ja -asiantuntijuuden muutoksesta. Minkälaisena he näkevät oman tulevan työnsä ja yhteistyökentän muiden viranomaisten kanssa? Selvää opiskelijavastausten mukaan on se, että turvallisuus halutaan pitää jatkossakin viranomaisen vastuulla ja välttää viimeiseen asti yksityisen sektorin liiallista vastuuta enempää kuin on pakko. Yhteistyötä halutaan edelleen lisätä, ja erityisesti tämä koskee viranomaisten välistä yhteistyötä. Tutkimus on tietoisesti rajattu koskemaan kahta turvallisuusalan viranomaistoimijaa, ammattikorkeakoulutuksen käyneitä poliiseja ja Puolustusvoimien Maanpuolustuskorkeakoulussa opiskelevia upseereita, joiden tehtävistä ja koulutuksesta on löydettävissä yhteisiä rajapintoja ja yhteistyön alueita. Kiinnostus syventyä valittuun kahteen ammattialaan johtuu myös siitä, että usein esimerkiksi sisäasianhallinnon strategioissa Puolustusvoimat jätetään ulkopuolelle varsinkin normaaliolojen yhteistyötä tarkasteltaessa tai vain yksittäisen maininnan asteelle. Sama huomio on havaittavissa puolustushallinnon strategioista. Tämä nousee esille erityisesti alueellista yhteistyötä tai viranomaisyhteistyötä pohdittaessa. Silti sekä sisäministeriön että puolustusministeriön hallinnonalan strategiat ym. perustuvat laajaan turvallisuuskäsitykseen, ja usein eri ammattikuntia analysoitaessa puhutaan tehtävistä, joita tekevät useat ammattikunnat ja professiot. Puhutaan niin sanotuista harmaista alueista. Ministeriöiden tahtotilassa ja toiminnassa on tutkimukseni mukaan nähtävissä ristiriita. Koulutuksen osalta yhteistyön lisääminen on mahdollista etenkin nyt, kun Poliisiammattikorkeakoulussa peruskoulutus on muuttunut ammattikorkeakoulutasoiseksi ja näin tämän ammattikunnan professioasema koulutuksen näkökulmasta on vahvistunut entisestään. Käsittelenkin tutkimuksessani kahta professiota professiotutkimuksen perinteisiä kriteereitä käyttäen, eli rinnastaessani näitä kahta ammattia. Rinnastettavuus koulujen kesken on tullut mahdolliseksi sekä tutkintojen että osaamisen tarkastelun näkökulmasta. Tämän myötä myös molempia korkeakouluja hyödyttävää yhteistyötä olisi mahdollista miettiä osana muutakin hallinnon tehostamista ja rauhan ajan viranomaistoimintaa.

Fast-Track Authority and International Trade Negotiations

Fast Track Authority (FTA) is the institutional procedure in the Unites States whereby Congress grants to the President the power to negotiate international trade agreements. Under FTA, Congress can only approve or reject negotiated trade deals, with no possibility of amending them. In this paper, we examine the determinants of FTA voting decisions and the implications of this institutional procedure for trade negotiations. We describe a simple two-country trade model, in which industries are unevenly distributed across con- stituencies. In the foreign country, trade negotiating authority is delegated to the executive, while in the home country Congress can retain the power to amend trade agreements. We show that legislators’ FTA voting behavior depends on the trade policy interests of their own constituencies as well as those of the majority of Congress. Empirical analysis of the determinants of all FTA votes between 1974 (when fast track was first introduced) and 2002 (when it was last granted) provides strong support for the predictions of our model.

Improving drug discovery using hybrid softcomputing methods

Virtual screening (VS) methods can considerably aid clinical research, predicting how ligands interact with drug targets. Most VS methods suppose a unique binding site for the target, but it has been demonstrated that diverse ligands interact with unrelated parts of the target and many VS methods do not take into account this relevant fact. This problem is circumvented by a novel VS methodology named BINDSURF that scans the whole protein surface in order to find new hotspots, where ligands might potentially interact with, and which is implemented in last generation massively parallel GPU hardware, allowing fast processing of large ligand databases. BINDSURF can thus be used in drug discovery, drug design, drug repurposing and therefore helps considerably in clinical research. However, the accuracy of most VS methods and concretely BINDSURF is constrained by limitations in the scoring function that describes biomolecular interactions, and even nowadays these uncertainties are not completely understood. In order to improve accuracy of the scoring functions used in BINDSURF we propose a hybrid novel approach where neural networks (NNET) and support vector machines (SVM) methods are trained with databases of known active (drugs) and inactive compounds, being this information exploited afterwards to improve BINDSURF VS predictions.

Improving drug discovery using a neural networks based parallel scoring function

Virtual Screening (VS) methods can considerably aid clinical research, predicting how ligands interact with drug targets. Most VS methods suppose a unique binding site for the target, but it has been demonstrated that diverse ligands interact with unrelated parts of the target and many VS methods do not take into account this relevant fact. This problem is circumvented by a novel VS methodology named BINDSURF that scans the whole protein surface to find new hotspots, where ligands might potentially interact with, and which is implemented in massively parallel Graphics Processing Units, allowing fast processing of large ligand databases. BINDSURF can thus be used in drug discovery, drug design, drug repurposing and therefore helps considerably in clinical research. However, the accuracy of most VS methods is constrained by limitations in the scoring function that describes biomolecular interactions, and even nowadays these uncertainties are not completely understood. In order to solve this problem, we propose a novel approach where neural networks are trained with databases of known active (drugs) and inactive compounds, and later used to improve VS predictions.

Not so fast: swimming behavior of sailfish during predator-prey interactions using high-speed video and accelerometry

Billfishes are considered among the fastest swimmers in the oceans. Despite early estimates of extremely high speeds, more recent work showed that these predators (e.g., blue marlin) spend most of their time swimming slowly, rarely exceeding 2 m s(-1). Predator-prey interactions provide a context within which one may expect maximal speeds both by predators and prey. Beyond speed, however, an important component determining the outcome of predator-prey encounters is unsteady swimming (i.e., turning and accelerating). Although large predators are faster than their small prey, the latter show higher performance in unsteady swimming. To contrast the evading behaviors of their highly maneuverable prey, sailfish and other large aquatic predators possess morphological adaptations, such as elongated bills, which can be moved more rapidly than the whole body itself, facilitating capture of the prey. Therefore, it is an open question whether such supposedly very fast swimmers do use high-speed bursts when feeding on evasive prey, in addition to using their bill for slashing prey. Here, we measured the swimming behavior of sailfish by using high-frequency accelerometry and high-speed video observations during predator-prey interactions. These measurements allowed analyses of tail beat frequencies to estimate swimming speeds. Our results suggest that sailfish burst at speeds of about 7 m s(-1) and do not exceed swimming speeds of 10 m s(-1) during predator-prey interactions. These speeds are much lower than previous estimates. In addition, the oscillations of the bill during swimming with, and without, extension of the dorsal fin (i.e., the sail) were measured. We suggest that extension of the dorsal fin may allow sailfish to improve the control of the bill and minimize its yaw, hence preventing disturbance of the prey. Therefore, sailfish, like other large predators, may rely mainly on accuracy of movement and the use of the extensions of their bodies, rather than resorting to top speeds when hunting evasive prey.

New artificial intelligence based tire size identification for fast and safe inflating cycle

Motor vehicle accidents are one of the main killers on the road. Modern vehicles have several safety features to improve the stability and controllability. The tire condition is critical to the proper function of the designed safety features. Under or over inflated tires adversely affects the stability of vehicles. It is generally the vehicle's user responsibility to ensure the tire inflation pressure is set and maintained to the required value using a tire inflator. In the tire inflator operation, the vehicle's user sets the desired value and the machine has to complete the task. During the inflation process, the pressure sensor does not read instantaneous static pressure to ensure the target value is reached. Hence, the inflator is designed to stop repetitively for pressure reading and avoid over inflation. This makes the inflation process slow, especially for large tires. This paper presents a novel approach using artificial neural network based technique to identify the tire size. Once the tire size is correctly identified, an optimized inflation cycle can be computed to improve performance, speed and accuracy of the inflation process. The developed neural network model was successfully simulated and tested for predicting tire size from the given sets of input parameters. The test results are analyzed and discussed in this paper.

On the fast Lanczos method for computation of eigenvalues of Hankel matrices using multiprecision arithmetics

The use of the fast Fourier transform (FFT) accelerates Lanczos tridiagonalisation method for Hankel and Toeplitz matrices by reducing the complexity of matrix-vector multiplication. In multiprecision arithmetics, the FFT has overheads that make it less competitive compared with alternative methods when the accuracy is over 10000 decimal places. We studied two alternative Hankel matrix-vector multiplication methods based on multiprecision number decomposition and recursive Karatsuba-like multiplication, respectively. The first method was uncompetitive because of huge precision losses, while the second turned out to be five to 14 times faster than FFT in the ranges of matrix sizes up to n = 8192 and working precision of b = 32768 bits we were interested in. We successfully applied our approach to eigenvalues calculations to studies of spectra of matrices that arise in research on Riemann zeta function. The recursive matrix-vector multiplication significantly outperformed both the FFT and the traditional multiplication in these studies.