Narrow Gap flux-cored arc welding of high strength shipbuilding steels

This thesis is part of the Arctic Materials Technologies Development –project. The research of the thesis was done in cooperation with Arctech Helsinki Shipyard, Lappeenranta University of Technology and Kemppi Oy. Focus of the thesis was to study narrow gap flux-cored arc welding of two high strength steels with three different groove angles of 20°, 10° and 5°. Welding of the 25 mm thick E500 TMCP and 10 mm thick EH36 steels was mechanized and Kemppi WisePenetration and WiseFusion processes were tested with E500 TMCP steel. EH36 steel test pieces were welded without Wise processes. Shielding gases chosen were carbon dioxide and a mixture of argon and carbon dioxide. Welds were tested with non-destructive and destructive testing methods. Radiographic, visual, magnetic particle and liquid penetrant testing proved that welds were free from imperfections. After non-destructive testing, welds were tested with various destructive testing methods. Impact strength, bending, tensile strength and hardess tests proved that mechanized welding and Wise processes produced quality welds with narrower gap. More inconsistent results were achieved with test pieces welded without Wise processes. Impact test results of E500 TMCP exceeded the 50 J limit on weld, set by Russian Maritime Register of Shipping. EH36 impact test results were much closer to the limiting values of 34 J on weld and 47 on HAZ. Hardness values of all test specimens were below the limiting values. Bend testing and tensile testing results fulfilled the the Register requirements. No cracking or failing occurred on bend test specimens and tensile test results exceeded the Register limits of 610 MPa for E500 TMCP and 490 MPa for EH36.

Adsorption of heavy metal ions and epoxidation catalysis using a new polyhedral oligomeric silsesquioxane

The objective of this research was the preparation of a silsesquioxane functionalized with eight chloropropyl chains (T8-PrCl) and of a new derivative functionalized with a pendant linear chain (2-amino-1,3,4-thiadiazole - ATD; T8-Pr-ATD). The two nanostructured materials were characterized by 13C and 29Si NMR, FTIR and elemental analysis. The new nanostructured material, octakis[3-(2-amino-1,3,4-thiadiazole)propyl] octasilsesquioxane (T8-Pr-ATD), was tested as a ligand for transition-metal ions with a special attention to adsorption isotherms. The adsorption was performed using a batchwise process and the organofunctionalized surface showed the ability to adsorb the metal ions Cu (II), Co (II), and Ni (II) from water and ethanol. The adsorption isotherms were fitted by Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (D-R) model. The kinetics of adsorption of metals were performed using three models such as pseudo-first order, pseudo-second order and Elovich. The Langmuir and Elovich models were the most appropriate to describe the adsorption and kinetic data, respectively. Furthermore, the T8-Pr-ATD was successfully applied to the analysis of environmental samples (river and sea water). Subsequently, a new nanomaterial was prepared by functionalization of the T8-Pr-ATD with a Mo (II) organometallic complex (T8-Pr-ATD-Mo). Only a few works in the literature have reported this type of substitution, and none dealt with ATD and Mo (II) complexes. The new Mo-silsesquioxane organometallic nanomaterial was tested as precursor in the epoxidation of cyclooctene and styrene. © 2012 Elsevier B.V.

Advanced liquid-liquid extraction : studies in a laboratory mixer-settler

A ten stage laboratory mixer-settler has been designed, constructed and operated with efficiencies up to 90%. The phase equilibrium data of the system acetic acid-toluene-water at different temperatures has been determined and correlated. Trials for prediction of these data have been investigated and a good agreement between the experimental data and the predictions obtained by the NRTL equation have been found. Extraction processes have been analysed. A model for determination of the time needed for a countercurrent stage-wise process to come to steady state has been derived. The experimental data was in reasonable agreement with this model. The discrete maximum principle has been applied to optimize the countercurrent extraction process and proved to be highly successful in predicting the optimum operating conditions which were confirmed by the experimental results. The temperature has proved to be a prosolvent for mass transfer in both directions but the temperature profile functioned as an anti solvent.

Hydrogen embrittlement contributions to fatigue crack growth in a structural steel

The detrimental effects of a hydrogen atmosphere on the fatigue resistance of BS 4360 steel have been assessed by a comparison of crack growth rates in air and hydrogen at a low cycling frequency (0.1Hz), and at a number of temperature (25, 50 and 80 °C). The crack propagation rates in air are almost independent of temperature over this range, but those measured in hydrogen differ by more than an order of magnitude between 25 and 80 °C. The greatest enhancement is seen at 25 °C and at high values of ΔK, the maximum occurring between 40–45 MPa √m at each temperature. There is little hydrogen contribution to crack growth at values of ΔK below 20 MPa √m for R = 0.1. The enhancement of crack growth rates is reflected by the presence of ‘quasi-cleavage’ facets on the fatigue fracture surfaces of specimens tested in hydrogen. These are most apparent where the greatest increases in growth rate are recorded. The facets show linear markings, which run both parallel and perpendicular to the direction of crack growth. The former are analogous to the ‘river’ lines noted on brittle cleavage facets, and reflect the propagation direction. The latter are more unusual, and indicate that facet formation by hydrogen embrittlement during fatigue is a step-wise process.

Assessing and reducing vulnerability to climate change: Moving from theory to practical decision-support

As climate change continues to impact socio-ecological systems, tools that assist conservation managers to understand vulnerability and target adaptations are essential. Quantitative assessments of vulnerability are rare because available frameworks are complex and lack guidance for dealing with data limitations and integrating across scales and disciplines. This paper describes a semi-quantitative method for assessing vulnerability to climate change that integrates socio-ecological factors to address management objectives and support decision-making. The method applies a framework first adopted by the Intergovernmental Panel on Climate Change and uses a structured 10-step process. The scores for each framework element are normalized and multiplied to produce a vulnerability score and then the assessed components are ranked from high to low vulnerability. Sensitivity analyses determine which indicators most influence the analysis and the resultant decision-making process so data quality for these indicators can be reviewed to increase robustness. Prioritisation of components for conservation considers other economic, social and cultural values with vulnerability rankings to target actions that reduce vulnerability to climate change by decreasing exposure or sensitivity and/or increasing adaptive capacity. This framework provides practical decision-support and has been applied to marine ecosystems and fisheries, with two case applications provided as examples: (1) food security in Pacific Island nations under climate-driven fish declines, and (2) fisheries in the Gulf of Carpentaria, northern Australia. The step-wise process outlined here is broadly applicable and can be undertaken with minimal resources using existing data, thereby having great potential to inform adaptive natural resource management in diverse locations.

An account of a method of preserving water, at sea, from putrefaction, and of restoring to the water ... : : to which is added a mode of impregnating water in lagre quatities with fixed air, for medicinal uses ... and like wise a process for the preparation of artificial yeast /

Mode of access: Internet.

Minimal information about T cell assays: the process of reaching the community of T cell immunologists in cancer and beyond.

Many assays to evaluate the nature, breadth, and quality of antigen-specific T cell responses are currently applied in human medicine. In most cases, assay-related protocols are developed on an individual laboratory basis, resulting in a large number of different protocols being applied worldwide. Together with the inherent complexity of cellular assays, this leads to unnecessary limitations in the ability to compare results generated across institutions. Over the past few years a number of critical assay parameters have been identified which influence test performance irrespective of protocol, material, and reagents used. Describing these critical factors as an integral part of any published report will both facilitate the comparison of data generated across institutions and lead to improvements in the assays themselves. To this end, the Minimal Information About T Cell Assays (MIATA) project was initiated. The objective of MIATA is to achieve a broad consensus on which T cell assay parameters should be reported in scientific publications and to propose a mechanism for reporting these in a systematic manner. To add maximum value for the scientific community, a step-wise, open, and field-spanning approach has been taken to achieve technical precision, user-friendliness, adequate incorporation of concerns, and high acceptance among peers. Here, we describe the past, present, and future perspectives of the MIATA project. We suggest that the approach taken can be generically applied to projects in which a broad consensus has to be reached among scientists working in fragmented fields, such as immunology. An additional objective of this undertaking is to engage the broader scientific community to comment on MIATA and to become an active participant in the project.

Deregulation of Railroads and Future Development Scenarios in Europe - Literature Analysis of Privatization Process Taken Place in US, UK and Sweden

Euroopan unionissa päätettiin jo yli vuosikymmen sitten, että rautatieliiketoiminta vapautetaan kilpailulle. Iso-Britanniasta olimäärä tulla esimerkkivaltio tämän prosessin käyttöönotossa. Pääideana oli säännöstelyn keventäminen, jolloin omistuspohja toimialalla laajenee ja rautateiden infrastruktuuri sekä toiminta parantuvat. Infrastruktuuri on määrä olla yhden organisaation hallinnassa ja raiteiden käyttöoikeus on kaikilla lupaehdot täyttävillä operaattoreilla, jotka kilpailevat keskenään matkustajista ja tavararahdeista. Kuitenkin Yhdysvalloissa ja eräissä Latinalaisen Amerikan maissa kilpailu on vapautettu siten, että rautatieyritys omistaa raideinfrastruktuurin, junat, tavarankuljetus- sekä matkustajavaunut. Iso-Britannian yksityistämistä pidettiin aluksi isonaepäonnistumisena: nopealla aikataululla sovellettiin jäykkiä transaktioperusteisia ulkoistamisstrategioita infrastruktuurin kunnossapitoon, jotka lopulta johtivat junien jatkuviin myöhästymisiin ja muutamaan tuhoisaan onnettomuuteen. Liiketoiminnallisessa mielessäkään ei oikein onnistuttu: infrastruktuurista vastaava yritys jouduttiin listaamaan pois Lontoon pörssistä, ja hallituksen oli pakko luoda tukipaketti pahasti velkaantuneen, vain marginaalisien investointien kohteena olleen yrityksen toimintaa varten (vaikka kapasiteettitarvetta oli markkinoilla). Myös rautatieoperaattorit olivat taloudellisessa ahdingossa ja vain määrätietoisten hallituksen laatimien pelastuspakettien avulla ala nousi syvimmästä kriisistään. Tästä huolimatta näiden negatiivisten sivuvaikutusten ohella koko ala pystyi kasvattamaan kysyntää, niin matkustaja- kuin rahtiliikenteenkin osalta. Vähenevän kysynnän trendi, joka alkoi 1970-luvulla, otti käännöksen parempaan. Toinen eurooppalaismaa, jolla on pitkät kokemukset yksityistämisestä, on Ruotsi. Tämä maatapaus on melko konservatiivinen verrattuna tilanteeseen edellisessä; vain rajattu määrä reittejä on avattu kilpailulle ja sopimukset tehdään kerralla pitkäksi aikaa eteenpäin. Ruotsin säännöstelyn purku osoittautui menestykseksi, koska tuottavuus onollut vakaassa kasvussa ja rautateiden markkinaosuus erityisesti matkustajapuolella on noussut merkittävästi, verrattuna muihin kuljetusmuotoihin. Kuitenkin kilpailua on käytännössä vähän tässä maassa ja parempiatuloksia on lupa odottaa, kun vain säännöstelyn purkaminen jatkuu. Viimeinen tutkimuksemme kohteena oleva maa on Yhdysvallat, joka alistutti rautatiet kilpailulle jo 1980-luvun alussa, käyttäen jo edellä mainittua vertikaalista integraatiota; tämä valinta on taas johtanut hyvin erilaisiin tuloksiin. Vaihtoehtoinen rakenteellinen uudistustapa on suosinut rahtivirtoja matkustajiin nähden, ja lopputuloksena tämä tapaus synnytti yrityksiä huolehtimaan toista näistä kahdesta pääasiakasryhmästä. Viimeaikaiset tulokset tästä yksityistämisprosessista ovat olleet hyviä: jäljellejääneiden yritysten voitot ovat kasvaneet, osinkoja ollaan kyetty jakamaan ja osakkeiden arvostus on noussut. Tässä tutkimusraportissa yritämme kolmen maatapauksen kautta esittää, miten yksityistämisprosessi tulee vaikuttamaan Euroopassa, kun kilpailu rautateillä vapautuu. Me käymmeläpi, mikä näistä kolmesta maaesimerkistä on kaikkein todennäköisin jaesitämme ehdotuksia siihen, miten valtiot voisivat välttää ei-haluttuja sivuvaikutuksia. Kolme maaesimerkkiä, ja lopuksi esitetty lyhyt tilastollinen analyysi osoittavat, että rautateillä on tulevaisuuden potentiaalia Euroopassa, ja kilpailun vapauttaminen on avain tämän potentiaalin realisointiin.

Forecasting the maximum compensation offer in the automobile BI claims negotiation process

Most motor bodily injury (BI) claims are settled by negotiation, with fewer than 5% of cases going to court. A well-defined negotiation strategy is thus very useful for insurance companies. In this paper we assume that the monetary compensation awarded in court is the upper amount to be offered by the insurer in the negotiation process. Using a real database, a log-linear model is implemented to estimate the maximal offer. Non-spherical disturbances are detected. Correlation occurs when various claims are settled in the same judicial verdict. Group wise heteroscedasticity is due to the influence of the forensic valuation on the final compensation amount. An alternative approximation based on generalized inference theory is applied to estimate confidence intervals on variance components, since classical interval estimates may be unreliable for datasets with unbalanced structures.

Step-Wise Changes in Glacier Flow Speed Coincide With Calving and Glacial Earthquakes at Helheim Glacier, Greenland

Geodetic observations show several large, sudden increases in flow speed at Helheim Glacier, one of Greenland's largest outlet glaciers, during summer, 2007. These step-like accelerations, detected along the length of the glacier, coincide with teleseismically detected glacial earthquakes and major iceberg calving events. No coseismic offset in the position of the glacier surface is observed; instead, modest tsunamis associated with the glacial earthquakes implicate glacier calving in the seismogenic process. Our results link changes in glacier velocity directly to calving-front behavior at Greenland's largest outlet glaciers, on timescales as short as minutes to hours, and clarify the mechanism by which glacial earthquakes occur. Citation: Nettles, M., et al. (2008), Step-wise changes in glacier flow speed coincide with calving and glacial earthquakes at Helheim Glacier, Greenland, Geophys. Res. Lett., 35, L24503, doi: 10.1029/2008GL036127.

Accessing chain length dependent termination rate coefficients of methyl methacrylate (MMA) via the reversible addition fragmentation chain transfer (RAFT) process

The RAFT-CLD-T methodology is demonstrated to be not only applicable to 1-substituted monomers such as styrene and acrylates, but also to 1,1-disubstituted monomers such as MMA. The chain length of the terminating macromolecules is controlled by CPDB in MMA bulk free radical polymerization at 80 degrees C. The evolution of the chain length dependent termination rate coefficient, k(t)(i,i), was constructed in a step-wise fashion, since the MMA/CPDB system displays hybrid behavior (between conventional and living free radical polymerization) resulting in initial high molecular weight polymers formed at low RAFT agent concentrations. The obtained CLD of k(t) in MMA polymerizations is compatible with the composite model for chain length dependent termination. For the initial chain-length regime, up to a degree of polymerization of 100, k(t) decreases with alpha (in the expression k(t)(i,i) = k(t)(0) . i(-alpha)) being close to 0.65 at 80 degrees C. At chain lengths exceeding 100, the decrease is less pronounced (affording an alpha of 0.15 at 80 degrees C). However, the data are best represented by a continuously decreasing nonlinear functionality implying a chain length dependent alpha.

Point-wise confidence interval estimation by neural networks: A comparative study based on automotive engine calibration.

In developing neural network techniques for real world applications it is still very rare to see estimates of confidence placed on the neural network predictions. This is a major deficiency, especially in safety-critical systems. In this paper we explore three distinct methods of producing point-wise confidence intervals using neural networks. We compare and contrast Bayesian, Gaussian Process and Predictive error bars evaluated on real data. The problem domain is concerned with the calibration of a real automotive engine management system for both air-fuel ratio determination and on-line ignition timing. This problem requires real-time control and is a good candidate for exploring the use of confidence predictions due to its safety-critical nature.

Analytic hierarchy process helps select site for limestone quarry expansion in Barbados

Site selection is a key activity for quarry expansion to support cement production, and is governed by factors such as resource availability, logistics, costs, and socio-economic-environmental factors. Adequate consideration of all the factors facilitates both industrial productivity and sustainable economic growth. This study illustrates the site selection process that was undertaken for the expansion of limestone quarry operations to support cement production in Barbados. First, alternate sites with adequate resources to support a 25-year development horizon were identified. Second, technical and socio-economic-environmental factors were then identified. Third, a database was developed for each site with respect to each factor. Fourth, a hierarchical model in analytic hierarchy process (AHP) framework was then developed. Fifth, the relative ranking of the alternate sites was then derived through pair wise comparison in all the levels and through subsequent synthesizing of the results across the hierarchy through computer software (Expert Choice). The study reveals that an integrated framework using the AHP can help select a site for the quarry expansion project in Barbados.

[meanings Of The Sickening Process For Patients With Systemic Lupus Erythematosus: A Review Of The Literature.]

Systemic lupus erythematosus is an autoimmune disease that causes many psychological repercussions that have been studied through qualitative research. These are considered relevant, since they reveal the amplitude experienced by patients. Given this importance, this study aims to map the qualitative production in this theme, derived from studies of experiences of adult patients of both genders and that had used as a tool a semi-structured interview and/or field observations, and had made use of a sampling by a saturation criterion to determine the number of participants in each study. The survey was conducted in Pubmed, Lilacs, Psycinfo e Cochrane databases, searching productions in English and Portuguese idioms published between January 2005 and June 2012. The 19 revised papers that have dealt with patients in the acute phase of the disease showed themes that were categorized into eight topics that contemplated the experienced process at various stages, from the onset of the disease, extending through the knowledge of the diagnosis and the understanding of the manifestations of the disease, drug treatment and general care, evolution and prognosis. The collected papers also point to the difficulty of understanding, of the patients, on what consists the remission phase, revealing also that this is a clinical stage underexplored by psychological studies.

[in Process Citation].

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