978 resultados para Exxon Valdez (Ship)
Resumo:
A technique to measure the concentration of Penicillium allii conidia in damp chamber experiments by spectrophotometry was developed. A negative linear correlation (R²=0.56) was observed between transmittance at 340 nm and the concentration of P. allii conidia in water agar 0.05%. The equation that relates transmittance (T) with concentration (conidia mL-1) (y) is: y = 9.3 10(6) - 86497 T. The method was assayed by inoculating 43 P. allii strains in two garlic cultivars. The method proved to be more rapid than the traditional use of a hemocytometer with an improved accuracy. The CV of the number of conidia per hemocytometer reticule was of 35.04%, while the transmittance CV was of 2.73%. The extreme values chosen for T were 40 and 80 because the sensitivity of the method decreased when concentrations of conidia were out of this range.
Resumo:
Tämän työn tarkoituksena oli tutkia miten rahtialuksen kansiluukut voitaisiin valmistaa mahdollisimman kevyiksi. Katettavan ruuman pinta-ala on n. 10 m x 40 m. Luukkujen suuresta jännevälistä johtuen, rakenteelta vaaditaan suurta jäykkyyttä. Erilaisina vaihtoehtoina tutkittiin vaahtomaista alumiinia, alumiinisia kennorakenteita ja polyuretaanisia sandwich-rakenteita. Työssä vertailtiin myös erilaisia geometrisia ratkaisuja, joilla kansiluukkujen jäykkyyttä pyrittiin lisäämään ja sitä kautta pääsemään pienempään materiaalin tarpeeseen. Geometriaa suunniteltaessa huomioitiin myös vaikutukset ruuman tilavuuteen ja lainsäädännön asettamat reunaehdot. Lainsäädännöstä saatiin esimerkiksi turvakaiteiden minimikorkeus, joka vaikuttaa suoraan ruuman tilavuuteen, kun aluksen korkeimmaksi kohdaksi on valittu laivan keskilinja ja tämä korkeus on annettu suunnittelun lähtötietona. Tietokoneavusteisen lujuuslaskennan avulla eri vaihtoehdoista muodostettiin elementtimallit. Malleja varioimalla ja tuloksia vertailemalla saatiin selville kevyin mahdollinen rakenne ja geometria. Malleista saatiin selville myös luukkujen tukireaktiovoimat, eli voimat, jotka luukut kohdistavat aluksen muihin rakenteisiin. Lisäksi työssä mietittiin erilaisia tapoja ruuman avaamiseen ja avaamistavan vaikutusta kansiluukkujen painoon, geometriaan ja ruuman tilavuuteen.
Resumo:
Electrical motors on a ship attackable to different factors which decrease these lifetimes. One of the main external factors on a ship which usually is a reason of the motor failure is a moisture condensation which decreases the motor winding insulation and increase a probability of the short circuit. Therefore, the protection against moisture is necessary for ship electrical motors. The motor should be protected against moisture all time when it does not operate. The necessity of such protection requires a lot of energy consumption. This master’s thesis is focused on the creation of the electrical motor thermal model and on the different methods of the motor protection against moisture analysis with energy consumption point of view.
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Marine traffic is expected to increase rapidly in the future, both in the Baltic Sea and in the Gulf of Finland. As the number of vessels in the area increases, so does the risk of serious marine accidents. To help prevent such accidents in the future, the International Maritime Organization (IMO) has put forth the International Safety Management Code (the ISM Code), which aims to improve the safety of the vessels. The second work package of the Development of maritime safety culture (METKU) project investigates the effects of the ISM Code and potential areas of improvement in maritime safety. The first phase in the work package used a literature review to determine how maritime safety culture could be improved. Continuous improvement, management commitment and personnel empowerment and motivation were found to be essential. In the second phase, shipping companies and administrators were interviewed. It was discovered that especially incident reporting based on continuous improvement was felt to be lacking. This third phase aims to take a closer look at incident reporting and suggest improvements based on the findings. Both the IMO and national legislation encourage shipping companies in incident reporting, and on the national level a shared incident reporting system (ForeSea) is being pushed forward. The objective of this research project was to find out the IMO’s attitude towards incident reporting, to establish a theoretical framework of reference in incident reporting, and to observe how reporting is actually being employed on the seas. Existing incident reporting systems were also researched. The study was carried out using a literature review and the results previously gathered in interviews. The results of phase two were elaborated further for themes relating to incident reporting. According to the findings of this research, the theoretical background of incident reporting dates back to the early 20th century. Although some theories are widely accepted, some have also received criticism. The lack of a concise, shared terminology poses major difficulties in maritime incident reporting and in determining its efficiency. A central finding is the fact that existing incident reporting focuses mostly on information flow away from the ship, whereas the backward information flow is much less planned and monitored. In incident reporting, both nationally and internationally, stakeholders are plenty. The information produced by these parties is scattered, however, and thus not very usable. Based on this research, the centralizing of this information should be made a priority. Traditionally, the success of incident reporting has been determined statistically, from the number of reported incidents. Yet existing reporting systems have not been designed with such statistical analysis in mind, so different methodologies might yield a more comprehensive view. The previous findings of seafarers and management (including shipping companies and administration) having differing views on safety work and safety management were backed up by the results of this study. Seafarers find seamanship and storytelling important, while management wants a more systematic and broad approach on safety matters. The research project was carried out by the Centre for Maritime Studies of the University of Turku, in the Kotka unit (Maritime Logistics Research), with coordination by the Kotka Maritime Research Centre. The major financiers of the project were the European Union and the city of Kotka. The financing authority was the Regional Council of Päijät-Häme. Partners in the project were the shipping companies Finnlines Oyj, Kristina Cruises Oy, Meriaura Oy and VG-Shipping Oy, and the ports of Helsinki, Kotka and Hamina. The partners provided both funding for the project and information for the research.
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A quantitative analysis is made on the correlation ship of thermodynamic property, i.e., standard enthalpy of formation (ΔH fº) with Kier's molecular connectivity index(¹Xv),vander waal's volume (Vw) electrotopological state index (E) and refractotopological state index (R) in gaseous state of alkanes. The regression analysis reveals a significant linear correlation of standard enthalpy of formation (ΔH fº) with ¹Xv, Vw, E and R. The equations obtained by regression analysis may be used to estimate standard enthalpy of formation (ΔH fº) of alkanes in gaseous state.
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B lymphocytes constitute a key branch of adaptive immunity by providing specificity to recognize a vast variety of antigens by B cell antigen receptors (BCR) and secreted antibodies. Antigen recognition activates the cells and can produce antibody secreting plasma cells via germinal center reaction that leads to the maturation of antigen recognition affinity and switching of antibody effector class. The specificity of antigen recognition is achieved through a multistep developmental pathway that is organized by interplay of transcription factors and signals through BCR. Lymphoid malignancies arise from different stages of development in abnormal function of transcriptional regulation. To understand the B cell development and the function of B cells, a thorough understanding of the regulation of gene expression is important. The transcription factors of the Ikaros family and Bcl6 are frequently associated with lymphoma generation. The aim of this study was to reveal the targets of Ikaros, Helios and Bcl6 mediated gene regulation and to find out the function of Ikaros and Helios in B cells. This study uses gene targeted DT40 B cell lines and establishes a role for Ikaros family factors Ikaros and Helios in the regulation of BCR signaling that is important at developmental checkpoints, for cell survival and in activation. Ikaros and Helios had opposing roles in the regulation of BCR signals. Ikaros was found to directly repress the SHIP gene that encodes a signaling lipid-metabolizing enzyme, whereas Helios had activating effect on SHIP expression. The findings demonstrate a balancing function for these two Ikaros family transcription factors in the regulation of BCR signaling as well as in the regulation of gene expression. Bcl6 was found to repress plasma cell gene expression program while maintaining gene expression profile of B cells. Analysis of direct Bcl6 target genes suggested novel mechanisms for Bcl6-mediated suppression of plasma cell differentiation and promoting germinal center phenotype.
Resumo:
Jäänmurtajien ja jäänmurtopalveluiden kehittymisen myötä Suomen teollisuus ja ulkomaankauppa on voinut tukeutua ympärivuotisiin merikuljetuksiin. Vuodesta 1889 lähtien, yli sadan vuoden ajan, jäänmurto oli valtion virkamiesten hoitamaa palvelua. Viimeisen seitsemän vuoden aikana jäänmurtajat ja palveluntuotanto on siirtynyt liikelaitoksen kautta valtion omistamalle osakeyhtiölle. Tarkoituksena on ollut monien muiden palveluiden tapaan saada myös jäänmurto kilpailutuksen piiriin. Tämän diplomityön tarkoituksena oli selvittää jäänmurto -liiketoiminnan kannattavuutta kilpailuun mahdollisesti osallistuvien yritysten näkökulmasta. Kannattavuutta selvitettiin kolmen tutkimuskokonaisuuden avulla. Tutkittavat osa-alueet olivat jäänmurron sopimukset, kustannusrakenne sekä muu mahdollinen jäänmurtajalla avovesikaudella suoritettava liiketoiminta. Tutkimus toteutettiin haastattelututkimuksena. Haastateltavina oli sekä jäänmurrossa mukana olevia ja siitä kiinnostuneita varustamoita että muita merenkulun sidosryhmiä, joiden toiminta vaikuttaa liiketoiminnan kannattavuuteen. Lisäksi tehtiin laskelmia kilpailutekijöiden selventämiseksi. Työn tuloksena ei pyritty saamaan ehdotonta tulosta kannattavuudesta, vaan tuloksina esiteltiin yritysten ja sidosryhmien näkemyksiä siitä, miten jäänmurron kilpailutusta voisi kehittää. Erityisesti haluttiin tuoda esille ne seikat, mitkä varustamot näkivät tärkeänä ja mitkä tukisivat heidän osallistumistaan mahdolliseen kilpailuun.
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This study compares different electric propulsion systems. Results of the analysis of all the advantages and disadvantages of the different propulsion systems are given. This thesis estimates possibilities to apply different diesel-electric propulsion concepts for different vessel types. Small and medium size vessel’s power ranges are studied. The optimal delivery system is chosen. This choice is made on the base of detailed study of the concepts, electrical equipment market and comparison of mass, volume and efficiency parameters. In this thesis three marine generators are designed. They are: salient pole synchronous generator and two permanent magnet synchronous generators. Their electrical, dimensional, cost and efficiency parameters are compared. To understand all the benefits diagrams with these parameters are prepared. Possible benefits and money savings are estimated. As the result the advantages, disadvantages and boundary conditions for the permanent magnet synchronous generator application in marine electric-power systems are found out.
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The objective of the pilotage effectiveness study was to come up with a process descrip-tion of the pilotage procedure, to design performance indicators based on this process description, to be used by Finnpilot, and to work out a preliminary plan for the imple-mentation of the indicators within the Finnpilot organisation. The theoretical aspects of pilotage as well as the guidelines and standards used were determined through a literature review. Based on the literature review, a process flow model with the following phases was created: the planning of pilotage, the start of pilo-tage, the act of pilotage, the end of pilotage and the closing of pilotage. The model based on the literature review was tested through interviews and observation of pilotage. At the same time an e-mail survey directed at foreign pilotage organisations, which included a questionnaire concerning their standards and management systems, operations procedures, measurement tools and their attitude to the passage planning, was conducted. The main issues in the observations and interviews were the passage plan and the bridge team co-operation. The phases of the pilotage process model emerged in both the pilotage activities and the interviews whereas bridge team co-operation was relatively marginal. Most of the pilotage organisations, who responded to the query, also use some standard-based management system. All organisations who answered the survey use some sort of a pilotage process model. According to the query, the main measuring tools for pilotage are statistical information concerning pilotage and the organisations, the customer feedback surveys, and financial results. Attitudes to-wards passage planning were mostly positive among the organisations. A workshop with pilotage experts was arranged where the process model constructed on the basis of the literature review was tuned to match practical pilotage. In the workshop it was determined that certain phases and the corresponding tasks, through which pilo-tage can be described as a process, were identifiable in all pilotage. The result of the workshop was a complemented process model, which separates incoming and outgoing traffic, as well as the fairway pilotage and harbour pilotage from each other. Addition-ally indicators divided according to the data gathering method were defined. Data con-cerning safety and traffic flow is gathered in the form of customer feedback. The pilot's own perceptions of the pilotage process are gathered through self-assessment. The measurement data which is connected to the phases of the pilotage process is generated e.g. by gathering statistics of the success of the pilot dispatches, the accuracy of the pi-lotage and the incidents that occurred during the pilotage, near misses, deviations and accidents. The measurement data is collected via the PilotWeb at the closing of the pilo-tage. A separate project and a project group with pilots also participating will be established for the deployment of the performance indicators. The phases of the project are: the definition phase, the implementation phase and the deployment phase. The purpose of the definition phase is to prepare questions for ship commanders concerning the cus-tomer feedback questionnaire and also to work out the self-assessment queries and the queries concerning the process indicators.
Resumo:
Kiristyvät päästörajoitukset ja muuttuvat säädökset ovat muokanneet laivanrakennusalaa energiatehokkaampaan ja ympäristöystävällisempään suuntaan. Energiatehokkuutta tutkitaan yksittäisistä laiteratkaisuista laivan operointitasolle asti. Tämä työ on tehty osana STX Finland Oy:n laivojen energiatehokkuuden tutkimusta. Työn tarkoituksena oli uudistaa laivojen sähkötaseen laskennassa käytettyjä kuormitustaulukoita ja kehittää operointialueen vaikutuksia huomioiva laskentamenetelmä. Uudistuksen taustalla oli tieto operointialueiden ympäristöolosuhteiden vaikutuksista sähkönkulutukseen ja työn tarkoituksena oli mahdollistaa suunnittelun myöhäisemmässä vaiheessa tehtävä operointialuekohtainen sähkönkulutustarkastelu. Sähkötaseen laskenta haluttiin vastaamaan enemmän todellista sähkönkulutusta. Aikaisemmin käytetystä mitoitusperusteisesta laskennasta haluttiin siirtyä todellisempien kuormien arviointiin laitteiden ja muuntajien turhan ylimitoituksen poistamiseksi. Kuormitustaulukoiden toimintaa yksinkertaistettiin ja taulukoista tehtiin helpommin mukautuvia, jotta erilaisten operointitilanteiden vertailu olisi mahdollista. Perinteisen taselaskennan rinnalle kehitettiin operointialueiden vaikutuksia huomioivat laskentataulukot. Uudet taulukot huomioivat komponenttien sähkönkulutuksen prosentuaalisen muutoksen operointialueittain sekä yksilöllisesti että kulutusryhmittäin. Laskentataulukoiden yhteyteen tehtiin kuvaajat havainnollistamaan alueittaisia kulutuseroja.
Resumo:
Työn tavoitteena on tutkia projektisuunnittelun ja projektijohtamisen perusteiden toteutu-mista projektityöskentelyssä julkishallinnon organisaatiossa. Tutkimuksen ydin on tunnistaa projektisuunnitelman, muutoshallinnan ja projektipäällikön osaamisen sekä johtamis-käyttäytymisen merkitys projektin onnistumisen näkökulmasta. Tutkimus käsittää projektihallinnan kokonaisuutena, jota toteutetaan suunnittelun, toimin-nan ja johtamisen vuoropuhelussa. Tutkimuksessa verrataan kirjallisuudesta esitettyä pro-jektisuunnittelun ja johtamisen teoriaa Liikenneviraston projektihallinnan ohjeistukseen, mallipohjiin ja kokemukseen projektipäällikön johtamiskäyttäytymisestä. Johtopäätöksinä esitetään Liikenneviraston projektiohjeistuksen kehittämiskohteet sekä Liikenneviraston projektijohtamisen kulttuurissa hyviksi johtajaominaisuuksiksi koetut projektipäällikön ominaisuudet. Keskeisenä havaintona tunnistetaan projektityöskentelyn kehämäinen luonne ja siitä aiheutuva jatkuvan suunnittelun, arvioinnin ja johtamisen tarve.
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With an increasingly growing demand for natural resources, the Arctic region has become an attractive area, holding about 15% of world oil. Ice shrinkage caused by global warming encourages the development of offshore and ship-building sectors. Russia, as one of the leading oil and gas production countries is participating actively in cold resistant materials research, since half of its territory belongs to the Arctic environment, which held considerable stores of oil. Nowadays most Russian offshore platforms are located in the Sakhalin Island area, which geographically does not belong to the Arctic, but has com-parable environmental conditions. Russia recently has manufactured several offshore platforms. It became clear that further development of the Arctic off-shore structures with necessary reliability is highly depending on the materials employed. This work pursues the following objectives: to provide a comprehensive review on Russian metals used for Arctic offshore structures on the base of standards, books, journal articles and companies reports to overview various Arctic offshore structures and its structural characteristics briefly discuss materials testing methods for low temperatures Master`s thesis focuses on specifications and description of Russian metals which are already in use and can be used for Arctic offshore structures. Work overviews several groups of steel, such as low carbon, low alloy, chromium containing steels, stainless steels, aluminium and nanostructured steels. Materials under discussion are grouped based on the standards, for instance the work covers shipbuilding and structural steels at the different sections. This paper provides an overview of important Russian Arctic offshore projects built for use in Russia and ordered by foreign countries. Future trends in development of the Arctic materials are discussed. Based on the information provided in this Master`s thesis it is possible to learn about Russian metals used for ships and offshore platforms operated in the Arctic region. Paper can be used as the comprehensive review of current materials, such as various steels, aluminium and nanomaterials.
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In ship and offshore terminal construction, welded cross sections are thick and the number of welds very high. Consequently, there are two aspects of great importance; cost and heat input. Reduction in the welding operation time decreases the costs of the work force and avoids excessive heat, preventing distortion and other weld defects. The need to increase productivity while using a single wire in the GMAW process has led to the use of a high current and voltage to improve the melting rate. Unfortunately, this also increases the heat input. Innovative GMAW processes, mostly implemented for sheet plate sections, have shown significant reduction in heat input (Q), low distortion and increase in welding speed. The aim of this study is to investigate adaptive pulsed GMAW processes and assess relevant applications in the high power range, considering possible benefits when welding thicker sections and high yield strength steel. The study experimentally tests the usability of adaptive welding processes and evaluates their effects on weld properties, penetration and shapes of the weld bead.The study first briefly reviews adaptive GMAW to evaluate different approaches and their applications and to identify benefits in adaptive pulsed. Experiments are then performed using Synergic Pulsed GMAW, WiseFusionTM and Synergic GMAW processes to weld a T-joint in a horizontal position (PB). The air gap between the parts ranges from 0 to 2.5 mm. The base materials are structural steel grade S355MC and filler material G3Si1. The experiment investigates heat input, mechanical properties and microstructure of the welded joint. Analysis of the literature reveals that different approaches have been suggested using advanced digital power sources with accurate waveform, current, voltage, and feedback control. In addition, studies have clearly indicated the efficiency of lower energy welding processes. Interest in the high power range is growing and a number of different approaches have been suggested. The welding experiments in this study reveal a significant reduction of heat input and a weld microstructure with the presence of acicular ferrite (AF) beneficial for resistance to crack propagation. The WiseFusion bead had higher dilution, due to the weld bead shape, and low defects. Adaptive pulse GMAW processes can be a favoured choice when welding structures with many welded joints. The total heat reduction mitigates residual stresses and the bead shape allows a higher amperage limit. The stability of the arc during the process is virtually spatter free and allows an increase in welding speed.
Resumo:
It is presented a test bed applied to studies on dynamics, control, and navigation of mobile robots. A cargo ship scale model was chosen, which can be radio-controlled or operated autonomously through an embedded control system. A control program, which manages on board mission execution, is implemented on a microcontroller. Navigation is based on an electronic compass, which includes automatic compensation for pitch and roll motions. Heading control loop is based on this sensor, and on a rudder positioning system. A propulsion control system is also implemented. Typical manoeuvres as the turning test and "zig-zag", were implemented and tested. They are included on a manoeuvre library, and can be accessed independently or in combined modes. The embedded system is also in charge of signal acquisition and storing during the missions. It is possible to analyse experiments on identification of ship dynamics, control, and navigation, through the data transferred to a PC by serial communication. Navigation is going to be improved by including inertial sensors on board, and a DGPS. Preliminary tests are aimed to ship identification, and manoeuvrability, using free model tests. Future steps include extending this system for developing other mobile robots as, ROVs, AUVs, and aerial vehicles.
Resumo:
Tämä tutkimus osallistuu tuottaja-osuuskuntiin liittyviin kestävän kehityksen keskusteluihin ja tarjoaa esimerkin pohjoismaisesta ruoantuotannon toimialasta. Tämä tutkimus seuraa kvalitatiivisen tutkimuksen suuntaviivoja ja Fairclough’n kriittinen diskurssianalyysi tarjoaa metodin yritystekstien analyysille. Kieli ymmärretään poststrukturalistisesta näkökulmasta, joka luo kielellisiä identiteettejä ja rakentaa vastuullisuuskeskustelua. Tutkimuksen tavoitteena on kuvata diskurssit, jotka rakentavat vastuullisuuskeskustelua kontekstissaan. Lisäksi tavoitteena on kuvata ja ymmärtää kuinka nämä diskurssit rakentavat rooleja ja identiteettejä ympärilleen sekä kuinka yritystekstit institutionalisoituvat ja vaikuttavat kontekstiinsa. Analyysi määrittää kolme vastuullisuusdiskurssia, jotka kuvaavat yrityskansalaisuutta, liiketoimintalähtöisyyttä ja integriteettiä. Diskurssien tavoitteiden, roolien, ja identiteettien ymmärrys ja vaikutus ympäristöön auttaa laajentamaan tietämystä kestävän kehityksen moniulotteisesta luonteesta. Lisäksi tutkimus muodostaa itsessään äänen osuuskuntatutkimukselle ja kestävän kehityksen ymmärryksen laajentamiselle.