976 resultados para Rocket engine
Resumo:
Tämä diplomityö kuvaa viestintä sovelluksen ytimen kehitystyön Symbian-alustalle. Koko sovelluksen vaatimuksena oli vastaamattomiin puheluihin vastaaminen ennalta määritellyillä tekstiviesteillä käyttäjän määrittelemien sääntöjen mukaisesti. Ei-toiminnallisia vaatimuksia olivat resurssien käytön vähentäminen ja uudelleenkäytön mahdollistaminen. Täten tämän työn tavoitteena oli kehittää ydin, joka kapseloi sovelluksen sellaisen toiminnallisuuden, joka on käyttöliittymästä riippumatonta ja uudelleenkäytettävää. Kehitystyössä ohjasi Unified Process, joka on iteroiva, käyttötapauksien ohjaama ja arkkitehtuurikeskeinen ohjelmistoprosessi. Se kannusti käyttämään myös muita teollisuudenalan vakiintuneita menetelmiä, kuten suunnittelumalleja ja visuaalista mallintamista käyttäen Unified Modelling Languagea. Suunnittelumalleja käytettiin kehitystyön aikana ja ohjelmisto mallinnettiin visuaalisesti suunnittelun edistämiseksi ja selkiyttämiseksi. Alustan palveluita käytettiin hyväksi kehitysajan ja resurssien käytön minimoimiseksi. Ytimen päätehtäviksi määrättiin viestien lähettäminen sekä sääntöjen talletus ja tarkistaminen. Sovelluksen eri alueet, eli sovelluspalvelin ja käyttöliittymää, pystyivät käyttämään ydintä ja sillä ei ollut riippuvuuksia käyttöliittymätasolle. Täten resurssien käyttö väheni ja uudelleenkäytettävyys lisääntyi. Viestien lähettäminen toteutettiin Symbian-alustan menetelmin. Sääntöjen tallettamiseen tehtiin tallennuskehys, joka eristää sääntöjen sisäisen ja ulkoisen muodon. Tässä tapauksessa ulkoiseksi tallennustavaksi valittiin relaatiotietokanta. Sääntöjen tarkastaminen toteutettiin tavanomaisella olioiden yhteistoiminnalla. Päätavoite saavutettiin. tämä ja muut hyviksi arvioidut lopputulokset, kuten uudelleenkäytettävyys ja vähentynyt resurssien käyttö, arveltiin juontuvan suunnittelumallien ja Unified Processin käytöstä. Kyseiset menetelmät osoittivat mukautuvansa pieniinkin projekteihin. Menetelmien todettiin myös tukevan ja kannustavan kehitystyön aikaista oppimista, mikä oli välttämätöntä tässä tapauksessa.
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The accretion of matter onto a massive black hole is believed to feed the relativistic plasma jets found in many active galactic nuclei (AGN). Although some AGN accelerate particles to energies exceeding 1012 electron volts and are bright sources of very-high-energy (VHE) γ-ray emission, it is not yet known where the VHE emission originates. Here we report on radio and VHE observations of the radio galaxy Messier 87, revealing a period of extremely strong VHE γ-ray flares accompanied by a strong increase of the radio flux from its nucleus. These results imply that charged particles are accelerated to very high energies in the immediate vicinity of the black hole.
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The vast majority of users don’t seek results beyond the second page offered by the search engine, so if a site fails to be among the top 20 (second page), it says that this page does not have good SEO and, therefore, is not visible to the user. The overall objective of this project is to conduct a study to discover the factors that determine (or not) the positioning of websites in a search engine.
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A rapid, expedient and enantioselective method for the synthesis of beta-hydroxy amines and monosubstituted aziridines in up to 99% e.e., via asymmetric transfer hydrogenation of a-amino ketones and cyclisation through treatment with tosyl chloride and base, is described. (1R,2R)-N-(para-toluenesulfonyl)-1,2-ethylenediamine with formic acid has been utilised as a ligand for the Ruthenium (II) catalysed enantioselective transfer hydrogenation of the ketones.The chiral 2-methyl aziridine, which is a potentially more efficient bonding agent for Rocket Solid Propellant has been successfully achieved.
Resumo:
App Engine on lyhenne englanninkielisistä termeistä application, sovellus ja engine, moottori. Kyseessä on Google, Inc. -konsernin toteuttama kaupallinen palvelu, joka noudattaa pilvimallin tietojenkäsittelyn periaatteita ja mahdollistaa asiakkaan oman sovelluskehityksen. Järjestelmään on mahdollista ohjelmoida itse ideoitu palvelu Internet - verkon välityksellä käytettäväksi, joko yksityisesti tai julkisesti. Kyse on siis hajautetusta palvelinjärjestelmästä, jonka tarjoaa dynaamisesti kuormitukseen sopeutuvan sovellusalustan, jossa asiakas ei vuokraa virtuaalikoneita. Myös järjestelmän tarjoama tallennuskapasiteetti on saatavilla joustavasti. Itse kandidaatintyössä syvennytään yksityiskohtaisemmin sovelluksen toteuttamiseen palvelussa, rajoitteisiin ja soveltuvuuteen. Alussa käydään läpi pilvikäsite, joista monilla tietokoneiden käyttäjillä on epäselvä käsitys. Erilaisia kokonaisuuksia voidaan luoda erittäin monella tavalla, joista rajaamme käsittelyn kohteeksi toteuttamiskelpoiset yleiset ratkaisut.
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Tämä Diplomityö keskittyy tutkimaan pilvisovelluskehitystä Google App Engine – pilvisovellusalustalle perustuen kuusi –vaiheiseen vesiputousmalliin sekä tutkimaan Google App Engine -pilvisovellusalustan tarjoamia mahdollisuuksia ja rajoituksia sovelluskehityksen muodossa. Tutkimuksen perusteella kuusi –vaiheinen vesiputousmalli soveltuu pilvisovelluskehitykseen,mikäli vaatimusmäärittely on tarkka jo sovelluskehityksen alkuvaiheessa. Tutkimuksen tuloksena syntyi vaatimusmäärittely MikkoMail –pilvisovellukselle. Vaatimusmäärittelyn pohjalta luotiin MikkoMail –pilvisovellus Google App Engine –pilvisovellusalustalle. Google App Engine –pilvisovellusalusta tukee vain Python- ja Java –ohjelmointikieliä eikä sisällä lainkaan ulkoista tietokantapalveluiden tukea. Tästä syystä Google App Engine -pilvisovellusalusta soveltuu pieniin, keskisuuriin ja pilottiprojektinomaisiin sovelluskehitysprojekteihin.
Resumo:
Search engine optimization & marketing is a set of processes widely used on websites to improve search engine rankings which generate quality web traffic and increase ROI. Content is the most important part of any website. CMS web development is now become very essential for most of organizations and online businesses to develop their online system and websites. Every online business using a CMS wants to get users (customers) to make profit and ROI. This thesis comprises a brief study of existing SEO methods, tools and techniques and how they can be implemented to optimize a content base website. In results, the study provides recommendations about how to use SEO methods; tools and techniques to optimize CMS based websites on major search engines. This study compares popular CMS systems like Drupal, WordPress and Joomla SEO features and how implementing SEO can be improved on these CMS systems. Having knowledge of search engine indexing and search engine working is essential for a successful SEO campaign. This work is a complete guideline for web developers or SEO experts who want to optimize a CMS based website on all major search engines.
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Diesel fuel is used widely in Brazil and worldwide. On the other hand, the growing environmental awareness leads to a greater demand for renewable energy resources. Thus, this study aimed to evaluate the use of different blends of soybean (Glycine max) methyl biodiesel and diesel in an ignition compression engine with direct injection fuel. The tests were performed on an electric eddy current dynamometer, using the blends B10, B50 and B100, with 10; 50 e 100% of biodiesel, respectively, in comparison to the commercial diesel B5, with 5% of biodiesel added to the fossil diesel. The engine performance was analyzed trough the tractor power take off (PTO) for each fuel, and the best results obtained for the power and the specific fuel consumption, respectively, were: B5 (44.62 kW; 234.87 g kW-1 h-1); B10 (44.73 kW; 233.78 g kW-1 h-1); B50 (44.11 kW; 250.40 g kW-1 h-1) e B100 (43.40 kW; 263.63 g kW-1 h-1). The best performance occurred with the use of B5 and B10 fuel, without significant differences between these blends. The B100 fuel showed significant differences compared to the other fuels.
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Brazil is doing a major effort to find alternatives to diesel oil as combustible. Some study lines are oriented to the development of vegetable oils used as fuel, as a source of getting cheaper and have higher energy density than the converted vegetable oils, and less risk of environmental contamination. The aim of this study was to evaluate the performance, the useful life of the lubricant and some components of a Diesel Cycle engine, with an electronic injection system, in a long-term test operating with a preheated blend (65°C) of 50% (v v-1) of soybean oil in petrodiesel. There was a reduction of the useful life of the injectors which presented failure because of high wear with 264 hours of operation and showed an increase in emissions of particulate matter (opacity) which may be assigned to the failures occurred in the injection system. An increase in the useful life of the lubricant, when compared with the literature was also observed. The electronic injection system may favor the burning of the tested fuel. The test was interrupted with 264 hours because of failures in the injection system.
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This study is dedicated to search engine marketing (SEM). It aims for developing a business model of SEM firms and to provide explicit research of trustworthy practices of virtual marketing companies. Optimization is a general term that represents a variety of techniques and methods of the web pages promotion. The research addresses optimization as a business activity, and it explains its role for the online marketing. Additionally, it highlights issues of unethical techniques utilization by marketers which created relatively negative attitude to them on the Internet environment. Literature insight combines in the one place both technical and economical scientific findings in order to highlight technological and business attributes incorporated in SEM activities. Empirical data regarding search marketers was collected via e-mail questionnaires. 4 representatives of SEM companies were engaged in this study to accomplish the business model design. Additionally, the fifth respondent was a representative of the search engine portal, who provided insight on relations between search engines and marketers. Obtained information of the respondents was processed qualitatively. Movement of commercial organizations to the online market increases demand on promotional programs. SEM is the largest part of online marketing, and it is a prerogative of search engines portals. However, skilled users, or marketers, are able to implement long-term marketing programs by utilizing web page optimization techniques, key word consultancy or content optimization to increase web site visibility to search engines and, therefore, user’s attention to the customer pages. SEM firms are related to small knowledge-intensive businesses. On the basis of data analysis the business model was constructed. The SEM model includes generalized constructs, although they represent a wider amount of operational aspects. Constructing blocks of the model includes fundamental parts of SEM commercial activity: value creation, customer, infrastructure and financial segments. Also, approaches were provided on company’s differentiation and competitive advantages evaluation. It is assumed that search marketers should apply further attempts to differentiate own business out of the large number of similar service providing companies. Findings indicate that SEM companies are interested in the increasing their trustworthiness and the reputation building. Future of the search marketing is directly depending on search engines development.
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The primary objective of this thesis is to assess how the backlink portfolio structure and off site Search Engine Optimisation (SEO) elements influence ranking of UK based online nursery shops. The growth of the internet use demanded significant effort from companies to optimize and increase their online presence in order to cope with the increasing online competition. The new e-Commerce technology - called Search Engine Optimisation - has been developed that helped increase website visibility of companies. The SEO process involves on site elements (i.e. changing the parameters of the company's website such as keywords, title tags and meta descriptions) and off site elements (link building and social media marketing activity). Link Building is based on several steps of marketing planning including keyword research and competitor analysis. The underlying goal of keyword research is to understand the targeted market through identifying relevant keyword queries that are used by targeted costumer group. In the analysis, three types (geographic, field and company’s strategy related) and seven sources of keywords has been identified and used as a base of analysis. Following the determination of the most popular keywords, allinanchor and allintitle search has been conducted and the first ten results of the searches have been collected to identify the companies with the most significant web presence among the nursery shops. Finally, Link Profiling has been performed where the essential goal was to understand to what extent other companies' link structure is different that the base company's backlinks. Significant difference has been found that distinguished the top three companies ranking in the allinanchor and allintitle search. The top three companies, „Mothercare”, „Mamas and Papas” and „Kiddicare” maintained significantly better metrics regarding domain and page authority on the main landing pages, the average number of outbound links for link portfolio metric and in number of backlinks. These companies also ranked among the highest in page authority distribution and followed external linking.
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The paper is devoted to study specific aspects of heat transfer in the combustion chamber of compression ignited reciprocating internal combustion engines and possibility to directly measure the heat flux by means of Gradient Heat Flux Sensors (GHFS). A one – dimensional single zone model proposed by Kyung Tae Yun et al. and implemented with the aid of Matlab, was used to obtain approximate picture of heat flux behavior in the combustion chamber with relation to the crank angle. The model’s numerical output was compared to the experimental results. The experiment was accomplished by A. Mityakov at four stroke diesel engine Indenor XL4D. Local heat fluxes on the surface of cylinder head were measured with fast – response, high – sensitive GHFS. The comparison of numerical data with experimental results has revealed a small deviation in obtained heat flux values throughout the cycle and different behavior of heat flux curve after Top Dead Center.
Resumo:
This master’s thesis is devoted to study different heat flux measurement techniques such as differential temperature sensors, semi-infinite surface temperature methods, calorimetric sensors and gradient heat flux sensors. The possibility to use Gradient Heat Flux Sensors (GHFS) to measure heat flux in the combustion chamber of compression ignited reciprocating internal combustion engines was considered in more detail. A. Mityakov conducted an experiment, where Gradient Heat Flux Sensor was placed in four stroke diesel engine Indenor XL4D to measure heat flux in the combustion chamber. The results which were obtained from the experiment were compared with model’s numerical output. This model (a one – dimensional single zone model) was implemented with help of MathCAD and the result of this implementation is graph of heat flux in combustion chamber in relation to the crank angle. The values of heat flux throughout the cycle obtained with aid of heat flux sensor and theoretically were sufficiently similar, but not identical. Such deviation is rather common for this type of experiment.
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A control law was designed for a satellite launcher ( rocket ) vehicle using eigenstructure assignment in order that the vehicle tracks a reference attitude and also to decouple the yaw response from roll and pitch manoeuvres and to decouple the pitch response from roll and yaw manoeuvres. The design was based on a complete linear coupled model obtained from the complete vehicle non linear model by linearization at each trajectory point. After all, the design was assessed with the vehicle time varying non-linear model showing a good performance and robustness. The used design method is explained and a case study for the Brazilian satellite launcher ( VLS Rocket ) is reported.
Resumo:
Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014