873 resultados para Requirements engineering process


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Työn tarkoituksena on selvittää, miten käyttötietämystä hyödynnetään prosessisuunnittelussa. Tavoitteena on löytää keinoja parantaa käyttötietämyksen hallintaa suunnitteluprosessin aikana ja selvittää, vaikuttaako tämä prosessisuunnittelun laatuun.Prosessisuunnittelun laatua arvioidaan seitsemällä kriteerillä, jotka ovat investointikustannukset, käyttökustannukset, turvallisuus, ympäristövaikutukset, käytettävyys, innovatiivisuus ja aikataulu. Suunnitteluprosessi jaetaan kolmeen vaiheeseen: esisuunnitteluun, perussuunnitteluun ja detaljisuunnitteluun. Prosessisuunnittelua, investointiprojektia, prosessisuunnittelun laatukriteerejä, suunnitteluprosessin eri vaiheita ja käyttötietämyksen luokittelua tarkastellaan yleisesti. Työssä selvitettiin käyttötietämyksen hyödyntämistä Kemiralla. Aluksi muotoiltiin yleisiä väittämiä käyttötietämyksen hyödyntämisestä Kemiran ulkopuolisten eri alojen asiantuntijoiden haastattelujen perusteella. Tämän jälkeen Kemiran prosessisuunnittelijat arvioivat väittämiä. Arvioiden perusteella tehtiin johtopäätöksiä yleisesti käyttötietämyksen hyödyntämisestä prosessisuunnittelussa. Seuraavaksi haastateltiin kahdessa erityyppisessä case-projektissa mukana olleita henkilöitä ja muotoiltiin yleiset väittämät näihin projekteihin sopiviksi. Projekteissa mukana olleet henkilöt arvioivat väittämiä, ja näiden arvioiden perusteella projekteja vertailtiin keskenään. Lopussa esitetään johtopäätökset kaikkien väittämien arvioiden perusteella. Johtopäätöksenä voidaan todeta, että käyttötietämystä voidaan hyödyntää kaikissa suunnittelun vaiheissa, mutta paras hyöty saadaan perus- ja detaljisuunnittelussa. Käyttötietämyksellä voidaan vaikuttaa joihinkin prosessisuunnittelun laatukriteereihin, kuten esimerkiksi käytettävyyteen ja turvallisuuteen enemmän kuin muihin. Kemiralle suositellaan nykyisten tiedonhallintamenetelmien kehittämistä, jotta käyttötietämyksen saatavuus ja sen siirtäminen paranisi. Pr

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The principal aim of this study is to clarify the requirements of segment reporting and compare the requirements with the actual! implementation on different business lines. The empirical part was concluded by interviewing randomly selected companies that are publicly listed on the Helsinki Exchanges. The theoretical part of the study (chapters 2 and 3) will give basic information about shifting to IAS -standards and the requirements of IAS -standards. In order to meet the principal aim, a pre-empiric research was conducted by studying the annual accounts (year 2002) of randomly selected companies that already follow the IAS -standards of reporting. The companies in the pre-empiric research consist of both domestic and foreign companies. The aim of the pre-empiric study was to give a basis for the interview process on the empiric part of the study. The study indicates that implementing segment reporting has not brought any major concerns or problems. This is due to the fact that most companies that were examined - being publicly listed companies - have traditionally had a clear division between their geographical and commercial segments, and also been obliged to give reports according to these segments. In case of changes in corporate structure, shifting on new lines of businesses or downsizing of operations, the problems in reporting according to IAS -standards, may arise. Such changes will also require changes on information systems, providing the essential information for segment reporting. According to this study, most companies choose the commercial segment as their primary segment for reporting. The pre-empiric study indicates, that most of the companies already following the IAS -standards, still have a lot of improvement to do, in order to meet all the IAS requirements.

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Maintenance is a part of system development and it is possible to develop operation models for accomplishing maintenance tasks. These models can be applied to individual maintenance tasks, maintenance projects and version management. Beneficial operation models makes maintenance more effective and they assist in managing various changes. The purpose of this thesis was to develop a maintenance process which can be used to remote administer network servers. This consisted of defining those operation models and technical specifications which enable to set up, manage changes, maintain and monitor resources of information systems that are located in several different sites. At first in this thesis the needs of the process were determined and requirements were defined based on those needs. The meaning of processes in maintenance of information systems, maintenance workflows and challenges were studied. Then current practical problems and disadvantages of maintenance work were analyzed in order to focus the development to proper issues. Because available operation models did not cover all the recent needs, new maintenance process which fulfilled the requirements was developed.

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Ultrafiltration (UF) is widely applied in different separation processes in the pulp and paper industry. The growing need to protect the environment, a lack of pure water and an interest in producing high-value chemicals from compounds present in process waters will probably lead to an increase in the use of UF in the pulp and paper industry. The efficiency and cost-effectiveness of a UF process depends on the applied membrane. The membrane should have a high and stable filtration capacity, a particular selectivity and a long operational lifetime. To meet these requirements a membrane should have a low fouling tendency. In addition, it should withstand the prevailing operational and chemical conditions. This thesis evaluates the performance and applicability of the regenerated cellulose (RC) membranes 00030T and C2 in the treatment of pulp and paper mill process waters based on the requirements above. The results demonstrated that both the tested RC membranes fulfilled well the requirement of high filtration capacity. In addition, in the filtration of a paper mill clear filtrate (CF) the RC membranes were not as greatly affected by variations in the CF quality as a polysulphone membrane. Furthermore, due to their extreme hydrophilicity and weak charge the fouling tendency of the membranes can be expected to be low in pulp and paper mill filtration applications. It is, however, known that fouling cannot be totally avoided even when the membrane is chosen very carefully. This study indicated that carbohydrates influenced negatively on permeability and caused fouling in the filtration of groundwood mill circulation water. Thus, a pre-treatment effectively reducing the amount of carbohydrates might help to maintain a stable capacity. However, the results of the thesis also showed that the removal of some of the possible foulants might just increase the harmful effect of others. Multivariate examination was useful in the understanding of the complicated factors causing the unstable capacity. The thesis also revealed that the 00030T and C2 membranes can be used at high pressure (max. tested pressure 12 bar). The C2 membrane, having a sponge-like substructure, was more pressure resistant, and its performance was more stable at high pressure compared to the UCO30T membrane containing macrovoids in its substructure. Both tested membranes can, according to the results, also be used at temperatures as high as 70°C in acidic, neutral and alkaline conditions. However, the use at extreme conditions might cause faster ageing of the membranes compared to ageing in neutral conditions. The thesis proved that both the tested RC membranes are very suitable for pulp and paper mill applications and that the membranes can be utilised in processes operating in challenging conditions. Thus, they could be used in more demanding applications than supposed earlier.

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Rapid manufacturing is an advanced manufacturing technology based on layer-by-layer manufacturing to produce a part. This paper presents experimental work carried out to investigate the effects of scan speed, layer thickness, and building direction on the following part features: dimensional error, surface roughness, and mechanical properties for DMLS with DS H20 powder and SLM with CL 20 powder (1.4404/AISI 316L). Findings were evaluated using ANOVA analysis. According to the experimental results, build direction has a significant effect on part quality, in terms of dimensional error and surface roughness. For the SLM process, the build direction has no influence on mechanical properties. Results of this research support industry estimating part quality and mechanical properties before the production of parts with additive manufacturing, using iron-based powders

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Inspections of pleasure boats in Spain can be carried out by collaborating entities of inspection, entities that must be authorized by the Maritime Administration. This authorization allows to perform effective inspections and technical controls of recreational crafts. Recreational crafts are subjected to surveys that are based on the registration list and on the material used in the hull. In addition, required safety equipment of the recreational boat depends on the distance that the recreational boat is authorized to navigate. Following data obtained from inspections of recreational craft, this paper aims to analyze information about hulls within dry and afloat conditions, about the equipment for rescue and safety, and about other nautical equipment; as well as to perform and improve different verifications during the inspections. All this information points to several aspects relevant for the optimization of the inspection process, the ultimate target being increasing efficiency and effectiveness, and ensuring more safety in recreational craft.

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The general task of clamping devise is to connect the parts to the machining centers so that the work piece could be fixed on its position during the whole machining process. Additionally, the work piece should be clamped easily and rapidly by the machine users. The purpose of this Master’s thesis project was to develop a product design and find out the dimensioning of a hydraulic vise system for Astex Engineering OY, which was taking care of the general principles of product design and development during the design process. Throughout the process, the needs of manufacturing and assembling were taken into consideration for the machinability and minimization of the cost of manufacturing. The most critical component of the clamping devise was modeled by FEM for the issue of strength requirements. This 3D model was created with Solidworks and FEM-analysis was done with Cosmos software. As the result of this design work, a prototype of the hydraulic vise was manufactured for Astex Engineering OY and the practical test.

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Tämän diplomityön tavoitteena on tutkia kattilalaitosten järjestelmällistä suunnittelua, huomioiden laitoksen elinkaariprosessit ja modulaarinen tuoterakenne. Kattilalaitokset investointituotteina toteutetaan tyypillisesti projektitoimintamallilla, jolloin jokainen toimitus suunnitellaan alusta kyseisen kohteen vaatimusten perusteella. Päätöksenteon peruste on laitosasiakkaiden osalta tyypillisesti hinta, jonkavuoksi laitoksen perusratkaisut tulee olla ennalta määriteltyjä ja toimitusprosessi huolellisesti suunniteltu, jotta kustannukset ja aikataulu ovat ennustettavissa. Projektitoimituksissa projektipäälliköllä on merkittävä vastuu myös suunnittelun onnistumisesta ja käytössä olevat projektinhallintamallit ovat hyvin tuotekeskeisiä, jolloin vaatimuksia ei riittävästi huomioida ja siten toteutettu laitosratkaisu ei täytä usein sidosryhmien asettamia vaatimuksia. Monimutkaisten järjestelmien kehittämiseen ja suunnitteluun on olemassa Systems Engineering - suunnittelumalli, jonka hyödyntäminen energiatekniikan alalla on ollut vielä vähäistä. Malli tarjoaa yhdessä ISO/ICE 15288 standardin kanssa valmiit prosessit tuotteen järjestelmälliselle suunnittelulle. Modulaariset tuoterakenteet ovat olleet perusvaatimus komponenttien toimitusten osalta, mutta laitosjärjestelmien tuotteistaminen on koettu vaikeaksi runsaan räätälöintitarpeen takia. Prosessimaisella toimintamallilla voidaan tuottaa modulaarisia tuoterakenteita ja tehostaa kattilalaitosten muutosten hallintaa. Tutkimuksessa tunnistettiin tyypilliset kattilalaitoksen suunnittelun prosessit kattilalaitosten kokonaistoimituksiin erikoistuneelle KPA Unicon Oy:lle.

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This thesis is focused on process intensification. Several significant problems and applications of this theme are covered. Process intensification is nowadays one of the most popular trends in chemical engineering and attempts have been made to develop a general, systematic methodology for intensification. This seems, however, to be very difficult, because intensified processes are often based on creativity and novel ideas. Monolith reactors and microreactors are successful examples of process intensification. They are usually multichannel devices in which a proper feed technique is important for creating even fluid distribution into the channels. Two different feed techniques were tested for monoliths. In the first technique a shower method was implemented by means of perforated plates. The second technique was a dispersion method using static mixers. Both techniques offered stable operation and uniform fluid distribution. The dispersion method enabled a wider operational range in terms of liquid superficial velocity. Using dispersion method, a volumetric gas-liquid mass transfer coefficient of 2 s-1 was reached. Flow patterns play a significant role in terms of the mixing performance of micromixers. Although the geometry of a T-mixer is simple, channel configurations and dimensions had a clear effect on mixing efficiency. The flow in the microchannel was laminar, but the formation of vortices promoted mixing in micro T-mixers. The generation of vortices was dependent on the channel dimensions, configurations and flow rate. Microreactors offer a high ratio of surface area to volume. Surface forces and interactions between fluids and surfaces are, therefore, often dominant factors. In certain cases, the interactions can be effectively utilised. Different wetting properties of solid materials (PTFE and stainless steel) were applied in the separation of immiscible liquid phases. A micro-scale plate coalescer with hydrophilic and hydrophobic surfaces was used for the continuous separation of organic and aqueous phases. Complete phase separation occurred in less than 20 seconds, whereas the separation time by settling exceeded 30 min. Fluid flows can be also intensified in suitable conditions. By adding certain additives into turbulent fluid flow, it was possible to reduce friction (drag) by 40 %. Drag reduction decreases frictional pressure drop in pipelines which leads to remarkable energy savings and decreases the size or number of pumping facilities required, e.g., in oil transport pipes. Process intensification enables operation often under more optimal conditions. The consequent cost savings from reduced use of raw materials and reduced waste lead to greater economic benefits in processing.

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One of the main industries which form the basis of Russian Economical structure is oil and gas. This industry is also playing a significant role for CIS countries. Oil and gas industry is developing intensively attracting foreign investments. This situation is providing sustainable development of machinery production for hazardous areas. Operating in oil and gas areas is always related with occurrence of explosion gas atmospheres. Machines for hazardous areas must be furnished with additional protection of different types. Explosion protection is regulated with standards according to which equipment must be manufactured. In Russia and CIS countries explosion-proof equipment must be constructed in compliance with GOST standards. To confirm that equipment is manufactured according to standards’ requirements and is safe and reliable it must undergo the approval procedure. Certification in Russia is governed by Federal Laws and legislation. Each CIS country has its own approval certificates and permissions for operating in hazardous areas.

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This paper presents a methodology to determine the parameters used in the simulation of delamination in composite materials using decohesion finite elements. A closed-form expression is developed to define the stiffness of the cohesive layer. A novel procedure that allows the use of coarser meshes of decohesion elements in large-scale computations is proposed. The procedure ensures that the energy dissipated by the fracture process is correctly computed. It is shown that coarse-meshed models defined using the approach proposed here yield the same results as the models with finer meshes normally used in the simulation of fracture processes

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The purpose of this study was to investigate the nature of co-operation between a project owner and an outside engineering consultant in combined heat and power plant implementation projects. Moreover, as another focal subject of the study was to familiarize the purchasing behavior of the energy producer and how an outside engineering consultant participated into different stages of the purchasing process. The study was carried out as a multiple case study including altogether six Finnish power plant implementation projects that had been taken into commercial use during 1995 – 2015. By adjusting the findings of empirical interview data and comparing those to the theoretical framework concerning, among others, Finnish energy production, engineering consulting businesses, delivery methods of construction project and finally the purchasing process, it can be concluded that especially in the power plant implementation projects in the past have a great influence to decisions made during the project. The role of the main engineering consultant is to act as an assistant, who helps to achieve the project goals successfully rather than an advisor who only knows how the project should be conducted. At least in these five project cases this was the case, meaning that the final decision power always remaining with project owner.

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Tehdyssä kirjallisuus- ja teoriakatsauksessa vuosien 2006 - 2010 välisenä aikana, Keski-Suomessa toimivan konepajateollisuuden järjestelmätoimittajayrityksen toimeksiannosta, pyrittiin muodostamaan kokonaiskuva laajasta tuotannonsuunnittelun ja -ohjauksen aihealueesta. Perustutkimuskysymykset liittyivät ns. MPC-systeemiin, jolla tarkoitetaan sitä, että tuotannonsuunnittelu- ja ohjauskysymyksissä on huomioitava aina henkilöiden, organisaation, teknologioiden ja prosessien muodostama kokonaisuus. Operatiivisen johtamisen tehtävänä on yrityksen tuotteita koskevan kysynnän ja tarjonnan tasapainottaminen niin, että resursseja käytettäisiin ja tarvittaisiin mahdollisimman vähän vastattaessa kysyntään asiakasvaatimukset huomioiden. Tuotantostrategian pohjalta on voitava rakentaa MPC-systeemi, jonka avulla ja jota kehittäen tuotanto saavuttaisi sille asetetut suorituskykytavoitteet mm. kustannusten, laadun, nopeuden, luotettavuuden sekä tuottavuuskehityksen osalta. Työssä tarkasteltiin yleisen kolmitasoisen viitekehyksen kautta ”perinteisistä MPC-systeemien perusratkaisuista” hierarkkisia, suunnittelu- ja laskentaintensiiviä, MRP-pohjaisia sekä yksinkertaistamiseen ja nopeuteen perustuvia JIT/Lean -menetelmiä. Tämä viitekehys käsittää: 1) kysynnän- ja resurssien hallinnan, 2) yksityiskohtaisemman kapasiteetin ja materiaalien hallinnan sekä 3) tarkemman tuotannon ja hankintojen ohjauksen sekä tuotannon lattiatason osa-alueet. Johtamisen ja MPC-systeemien kehittämisen ”uusina aaltoina ja näkökulmina” raportissa käsiteltiin myös johtamisen eri koulukuntia sekä em. viitekehyksen pohjalta tarvittavia tietojärjestelmiä. Olennaisimpana johtopäätöksenä todettiin, että MRP-pohjaisten ratkaisujen lisäksi, etenkin monimutkaisia tuotteita tilausohjautuvasti valmistavien kappaletavarateollisuuden yritysten, on mahdollisesti hyödynnettävä myös kehittyneempiä suunnittelu- ja ohjausjärjestelmiä. Lisäksi huomattiin, että ”perinteisten strategioiden” rinnalle yritysten on nostettava myös tieto- ja viestintäteknologiastrategiat. On tärkeää ymmärtää, että täydellistä MPC-systeemiä ei ole vielä keksitty: jokaisen yrityksen tehtäväksi ja vastuulle jää ”oman totuutensa” muodostaminen ja systeeminsä rakentaminen sen pohjalta.

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Research focus of this thesis is to explore options for building systems for business critical web applications. Business criticality here includes requirements for data protection and system availability. The focus is on open source software. Goals are to identify robust technologies and engineering practices to implement such systems. Research methods include experiments made with sample systems built around chosen software packages that represent certain technologies. The main research focused on finding a good method for database data replication, a key functionality for high-availability, database-driven web applications. Research included also finding engineering best practices from books written by administrators of high traffic web applications. Experiment with database replication showed, that block level synchronous replication offered by DRBD replication software offered considerably more robust data protection and high-availability functionality compared to leading open source database product MySQL, and its built-in asynchronous replication. For master-master database setups, block level replication is more recommended way to build high-availability into the system. Based on thesis research, building high-availability web applications is possible using a combination of open source software and engineering best practices for data protection, availability planning and scaling.

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Diplomityön tavoitteena oli kuvata hitsauksen laadunhallintaa sekä hitsauksen laadunhallintajärjestelmän rakentamista offshore-teollisuuden konepajaan standardin ISO 3834-2 mukaisesti. Diplomityö koostuu teoriaosasta sekä käytännön osasta. Teoriaosa käsittelee laadunhallintaa yleisesti, minkä jälkeen se tarkentuu käsittelemään hitsauksen laadunhallintaa. Esimerkkinä on esitetty standardin NORSOK M-101 mukaisia laatuvaatimuksia. Laadunhallintaan liittyy oleellisesti myös hitsausliitoksen NDT-tarkastaminen, josta on käsitelty silmämääräinen tarkastus ja ultraäänitarkastus. Teoriaosan lopussa on käsitelty hitsauksen työturvallisuutta sekä hitsauksen laadunvalvontaa online-seurantajärjestelmällä. Käytännön osassa kerrotaan hitsauksen laatujärjestelmän rakentamisesta Meteco Oy:n Kuhmoisten tehtaalla. Yrityksen nykytilanne kartoitettiin, minkä jälkeen ryhdyttiin rakentamaan hitsauksen laadunhallintajärjestelmää. Tuloksena syntyi hitsauksen laatukäsikirja, joka pohjautuu standardiin ISO 3834-2. Käytännön osuudessa on kerrottu myös online-seurantajärjestelmän soveltuvuudesta alihankintakonepajan käyttöön. Hitsauksen laatujärjestelmän rakentamiseen kuului henkilöstön koulutustilaisuudet, joissa informoitiin edellä mainitun laatukäsikirjaan kuuluvista asioista. Tästä syntyi yritykseen myös koulutusohjelmasuunnitelma, joka antaa valmiudet yrityksen henkilökunnalle kehittyä työssään ja näin tehostaa toimintaa.