951 resultados para Garment cutting


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One of the most difficult procedures in digestive-tract surgery is esophago-jejunal anastomosis following total gastrectomy. Cost/benefit analysis of this procedure justifies the use of mechanical staplers, in spite of their high cost. A technical variant of the side-to-side esophago-jejunal anastomosis is presented, which incorporates the use of a cutting linear stapler. Technical maneuvers are easy to perform, the cost of the cutting linear stapler is smaller than the circular ones, the amplitude of the anastomosis is wider and the likelihood of fistulae is smaller when compared to other techniques. The side-to-side esophago-jejunal anastomosis with the cutting linear stapler is always complemented by a manual suture.

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Diplomityössä tavoitteena oli suunnitella kantava modulaarinen kehikkorakenne, joka soveltuu käytettäväksi erilaisissa tasoratkaisuissa. Suunnittelumetodina käytettiin järjestelmällistä tuotesuunnittelua. Rakenteen tuli olla modulaarinen, valmistettavissa laserleikkaamalla ja toteutettu ruuviliitoksilla. Lisäksi kehikkorakenteen suunnittelussa pyrittiin optimaalisimpaan ratkaisuun niin teknisen kuin taloudellisenkin toteutuksen kannalta. Premekon Oy investoi vuonna 2009 laserleikkuukeskukseen, jossa pystytään leikkaamaan levyjä ja palkkeja. Yhdessä oikeanlaisen tuotesuunnittelun kanssa laserleikkuukeskuksella pystytään valmistamaan tuotteita suurella tuotantotehokkuudella. Kantavan modulaarisen kehikkorakenteen kehittäminen mahdollisti laserleikkuun aiempaa tehokkaamman hyödyntämisen. Työssä tarkasteltiin yksityiskohtaisemmin erilaisten profiilien soveltuvuutta laserleikattavaksi, osien muotoilua, liitosten yhteensopivuutta ja lujuutta.

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Human trafficking is not a new phenomenon. It has existed in various forms for ages around the world. Some researchers have even compared it to slavery, calling it the modern form of slavery in the 21st century. This study is particularly interested in the role of work-related human trafficking in Finnish business. In order for something to be called work-related human trafficking, the concepts of forced labour and human trafficking have to overlap. From the economic point of view, human trafficking is governed by the laws of supply and demand. In many countries the global pressure on cutting costs has created two trends: the increased supply of migrant workers and the deregulation of labour markets. These competitive pressures can have an adverse impact on the conditions of employment and, in the worst cases, can lead to forced labour and trafficking. In fact, trafficking has become one of the most profitable illicit industries worldwide, generating tremendous profits due to its low costs and huge profits. Therefore, it is important to investigate the phenomenon from the business point of view. This study is a qualitative research conducted by using theme interviews as a research approach. Altogether 13 interviews have been conducted and some secondary data has been used in order to find out what the role of human trafficking is in Finnish business. The special sectors investigated are the Finnish construction and service sectors. The theory framework used in this study follows the stakeholder approach. The relevant stakeholder groups for this study are: ‘institutions and authorities’, ‘law enforcement’, ‘management’ and ‘employees – potential victims’ of trafficking. With the help of these stakeholder groups, a holistic picture of the phenomenon is formed. It can be concluded that the role of human trafficking is complicated but it does exist in Finnish business. It appears in low-cost business sectors where the demand for cheap labour is high. Thus, often the victims are foreigners who do not know the culture or the Finnish conditions of employment. Especially smaller Finnish companies are at risk of getting involved in human trafficking or related exploitation cases since monitoring is much more scarce in these firms than in larger companies. The risk of human trafficking and exploitation is also higher at the bottom of the complicated subcontracting chains or when using foreign recruitment agencies. Thus, the study believes that active and intensive collaboration between the company’s different stakeholder groups is needed in order to prevent work-related human trafficking from flourishing in Finland.

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Työssä suunniteltiin uittonippujen sidonnan koneellistamiseksi tarvittavan sidontalangan käsittelylaitteisto. Sen toiminnalliset pääkomponentit ovat langan ohjauskouru, syöttölaite sekä solminta- ja katkaisulaitteet. Lisäksi työssä tehtiin koneelliseen sidontaan sopivan sidontalangan määrityksiä.

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Two outbreaks of zigomycosis with rhinofacial and two other with rhinopharyngeal lesions involving fungi with filamentous coaenocytic hyphae characteristic of entomoph-thoramycetous fungi are reported in the state of Paraíba, northeastern Brazil. One outbreak of rhinofacial zygomycosis occurred during the rainy season affecting 5 sheep. Another outbreak of the clinical form affected one out of 40 sheep during the dry season. Common clinical signs of the rhinofacial infection were bilateral serosanguineous nasal discharge with swelling of nostrils, upper lip, and the skin of the face. At necropsy the nasal mucosa showed dark brownish ulcerated areas which extended from the mucocutaneous region to 10cm inside the nasal vestibule. The mucosa of the hard palate was also ulcerated. The cutting surface of nostrils and palate showed a brownish or red spongeous tissue of friable consistency. One outbreak of rhinopharyngitis took place on an irrigated coconut farm; 7 out of 60 adult sheep were affected. Another outbreak affected a sheep in a flock of 80 during the dry season. Clinical signs as noisy respiration and dyspnoea due to mechanical blockage of the nasal cavities, swelling of the nostrils, and serosanguineous nasal discharge were observed. Six out of 8 sheep in this group showed exophthalmia, keratitis and unilateral corneal ulceration of the eye. The sheep either died of their infection or were euthanized after a clinical course of 7-30 days. At necropsy there was a dense yellow exudate in the nasopharyngeal area affecting the ethmoidal region, turbinate bones, paranasal sinuses, hard and soft palates, orbital cavity, pharynges, regional muscles and lymph nodes. Histopathologically both forms of the disease showed multifocal granulomas with an eosinophilic necrotic reaction (Splendore-Hoeppli phenomenon) containing ribbon-type coenocytic hyphae with 7-30mum in diameter similar to hyphae of zygomycetous fungi, possibly Conidiobolus spp. Outbreaks of both forms of mycotic rhinitis are common in northeastern Brazil and in other regions of the country.

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The aim of the thesis was to find the effects of World Trade Organization and economic integration on the wood sourcing process from Russia to Finland and to the European Union. Also, the fo reign direct investments to Russian forest industry are studied within the WTO and Economic integration framework. Qualitative interviews were carried out as primary data (total of 5 interviews). Research studies and articles regarding the same subject were used as secondary data. Results show that companies may increase their volumes of imported timber from Russia due to the reduction of custom tariffs. Russian companies are becoming more productive, but there are still several problems with legislation, infrastructure, availability and harvesting profitability in some areas. These suggest that sourcing process may not be profitable in the future. The Russian forest industry sector will not gain significant foreign direct investments in the recent years because of the infrastructure and overall atmosphere of investments. Forest industry is not seen as profitable enough. The demand for cellulose and paper in Russia is not increasing fast enough and the cost inflation is cutting the profits made from producing in Russia.

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It is known already from 1970´s that laser beam is suitable for processing paper materials. In this thesis, term paper materials mean all wood-fibre based materials, like dried pulp, copy paper, newspaper, cardboard, corrugated board, tissue paper etc. Accordingly, laser processing in this thesis means all laser treatments resulting material removal, like cutting, partial cutting, marking, creasing, perforation etc. that can be used to process paper materials. Laser technology provides many advantages for processing of paper materials: non-contact method, freedom of processing geometry, reliable technology for non-stop production etc. Especially packaging industry is very promising area for laser processing applications. However, there are only few industrial laser processing applications worldwide even in beginning of 2010´s. One reason for small-scale use of lasers in paper material manufacturing is that there is a shortage of published research and scientific articles. Another problem, restraining the use of laser for processing of paper materials, is colouration of paper material i.e. the yellowish and/or greyish colour of cut edge appearing during cutting or after cutting. These are the main reasons for selecting the topic of this thesis to concern characterization of interaction of laser beam and paper materials. This study was carried out in Laboratory of Laser Processing at Lappeenranta University of Technology (Finland). Laser equipment used in this study was TRUMPF TLF 2700 carbon dioxide laser that produces a beam with wavelength of 10.6 μm with power range of 190-2500 W (laser power on work piece). Study of laser beam and paper material interaction was carried out by treating dried kraft pulp (grammage of 67 g m-2) with different laser power levels, focal plane postion settings and interaction times. Interaction between laser beam and dried kraft pulp was detected with different monitoring devices, i.e. spectrometer, pyrometer and active illumination imaging system. This way it was possible to create an input and output parameter diagram and to study the effects of input and output parameters in this thesis. When interaction phenomena are understood also process development can be carried out and even new innovations developed. Fulfilling the lack of information on interaction phenomena can assist in the way of lasers for wider use of technology in paper making and converting industry. It was concluded in this thesis that interaction of laser beam and paper material has two mechanisms that are dependent on focal plane position range. Assumed interaction mechanism B appears in range of average focal plane position of 3.4 mm and 2.4 mm and assumed interaction mechanism A in range of average focal plane position of 0.4 mm and -0.6 mm both in used experimental set up. Focal plane position 1.4 mm represents midzone of these two mechanisms. Holes during laser beam and paper material interaction are formed gradually: first small hole is formed to interaction area in the centre of laser beam cross-section and after that, as function of interaction time, hole expands, until interaction between laser beam and dried kraft pulp is ended. By the image analysis it can be seen that in beginning of laser beam and dried kraft pulp material interaction small holes off very good quality are formed. It is obvious that black colour and heat affected zone appear as function of interaction time. This reveals that there still are different interaction phases within interaction mechanisms A and B. These interaction phases appear as function of time and also as function of peak intensity of laser beam. Limit peak intensity is the value that divides interaction mechanism A and B from one-phase interaction into dual-phase interaction. So all peak intensity values under limit peak intensity belong to MAOM (interaction mechanism A one-phase mode) or to MBOM (interaction mechanism B onephase mode) and values over that belong to MADM (interaction mechanism A dual-phase mode) or to MBDM (interaction mechanism B dual-phase mode). Decomposition process of cellulose is evolution of hydrocarbons when temperature is between 380- 500°C. This means that long cellulose molecule is split into smaller volatile hydrocarbons in this temperature range. As temperature increases, decomposition process of cellulose molecule changes. In range of 700-900°C, cellulose molecule is mainly decomposed into H2 gas; this is why this range is called evolution of hydrogen. Interaction in this range starts (as in range of MAOM and MBOM), when a small good quality hole is formed. This is due to “direct evaporation” of pulp via decomposition process of evolution of hydrogen. And this can be seen can be seen in spectrometer as high intensity peak of yellow light (in range of 588-589 nm) which refers to temperature of ~1750ºC. Pyrometer does not detect this high intensity peak since it is not able to detect physical phase change from solid kraft pulp to gaseous compounds. As interaction time between laser beam and dried kraft pulp continues, hypothesis is that three auto ignition processes occurs. Auto ignition of substance is the lowest temperature in which it will spontaneously ignite in a normal atmosphere without an external source of ignition, such as a flame or spark. Three auto ignition processes appears in range of MADM and MBDM, namely: 1. temperature of auto ignition of hydrogen atom (H2) is 500ºC, 2. temperature of auto ignition of carbon monoxide molecule (CO) is 609ºC and 3. temperature of auto ignition of carbon atom (C) is 700ºC. These three auto ignition processes leads to formation of plasma plume which has strong emission of radiation in range of visible light. Formation of this plasma plume can be seen as increase of intensity in wavelength range of ~475-652 nm. Pyrometer shows maximum temperature just after this ignition. This plasma plume is assumed to scatter laser beam so that it interacts with larger area of dried kraft pulp than what is actual area of beam cross-section. This assumed scattering reduces also peak intensity. So result shows that assumably scattered light with low peak intensity is interacting with large area of hole edges and due to low peak intensity this interaction happens in low temperature. So interaction between laser beam and dried kraft pulp turns from evolution of hydrogen to evolution of hydrocarbons. This leads to black colour of hole edges.

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More than ever, education organisations are experiencing the need to develop new services and processes to satisfy expanding and changing customer needs and to adapt to the environmental changes and continually tightening economic situation. Innovation has been found in many studies to have a crucial role in the success of an organisation, both in the private and public sectors, in formal education and in manufacturing and services alike. However, studies concerning innovation in non-formal adult education organisations, such as adult education centres (AECs) in Finland, are still lacking. This study investigates innovation in the non-formal adult education organisation context from the perspective of organisational culture types and social networks. The objective is to determine the significant characteristics of an innovative non-formal adult education organisation. The analysis is based on data from interviews with the principals and fulltime staff of four case AECs. Before the case study, a pre-study phase is accomplished in order to obtain a preliminary understanding of innovation at AECs. The research found strong support for the need of innovation in AECs. Innovation is basically needed to accomplish the AEC system’s primary mission mentioned in the ACT on Liberal Adult Education. In addition, innovation is regarded vital to institutes and may prevent their decline. It helps the institutes to be more attractive, to enter new market, to increase customer satisfaction and to be on the cutting edge. Innovation is also seen as a solution to the shortage of resources. Innovative AECs search actively for additional resources for development work through project funding and subsidies, cooperation networks and creating a conversational and joyful atmosphere in the institute. The findings also suggest that the culture type that supports innovation at AECs is multidimensional, with an emphasis on the clan and adhocratic culture types and such values as: dynamism, future orientation, acquiring new resources, mistake tolerance, openness, flexibility, customer orientation, a risk-taking attitude, and community spirit. Active and creative internal and external cooperation also promote innovation at AECs. This study also suggests that the behaviour of a principal is crucial. The way he or she shows appreciation the staff, encouragement and support to the staff and his or her approachability and concrete participation in innovation activities have a strong effect on innovation attitudes and activities in AECs.

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Permanent magnet generators (PMG) represent the cutting edge technology in modern wind mills. The efficiency remains high (over 90%) at partial loads. To improve the machine efficiency even further, every aspect of machine losses has to be analyzed. Additional losses are often given as a certain percentage without providing any detailed information about the actual calculation process; meanwhile, there are many design-dependent losses that have an effect on the total amount of additional losses and that have to be taken into consideration. Additional losses are most often eddy current losses in different parts of the machine. These losses are usually difficult to calculate in the design process. In this doctoral thesis, some additional losses are identified and modeled. Further, suggestions on how to minimize the losses are given. Iron losses can differ significantly between the measured no-load values and the loss values under load. In addition, with embedded magnet rotors, the quadrature-axis armature reaction adds losses to the stator iron by manipulating the harmonic content of the flux. It was, therefore, re-evaluated that in salient pole machines, to minimize the losses and the loss difference between the no-load and load operation, the flux density has to be kept below 1.5 T in the stator yoke, which is the traditional guideline for machine designers. Eddy current losses may occur in the end-winding area and in the support structure of the machine, that is, in the finger plate and the clamping ring. With construction steel, these losses account for 0.08% of the input power of the machine. These losses can be reduced almost to zero by using nonmagnetic stainless steel. In addition, the machine housing may be subjected to eddy current losses if the flux density exceeds 1.5 T in the stator yoke. Winding losses can rise rapidly when high frequencies and 10–15 mm high conductors are used. In general, minimizing the winding losses is simple. For example, it can be done by dividing the conductor into transposed subconductors. However, this comes with the expense of an increase in the DC resistance. In the doctoral thesis, a new method is presented to minimize the winding losses by applying a litz wire with noninsulated strands. The construction is the same as in a normal litz wire but the insulation between the subconductors has been left out. The idea is that the connection is kept weak to prevent harmful eddy currents from flowing. Moreover, the analytical solution for calculating the AC resistance factor of the litz-wire is supplemented by including an end-winding resistance in the analytical solution. A simple measurement device is developed to measure the AC resistance in the windings. In the case of a litz-wire with originally noninsulated strands, vacuum pressure impregnation (VPI) is used to insulate the subconductors. In one of the two cases studied, the VPI affected the AC resistance factor, but in the other case, it did not have any effect. However, more research is needed to determine the effect of the VPI on litz-wire with noninsulated strands. An empirical model is developed to calculate the AC resistance factor of a single-layer formwound winding. The model includes the end-winding length and the number of strands and turns. The end winding includes the circulating current (eddy currents that are traveling through the whole winding between parallel strands) and the main current. The end-winding length also affects the total AC resistance factor.

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Paremmin lastuttavia M-käsiteltyjä teräksiä on käytetty yrityksissä jo yli 20 vuoden ajan. Ominaisuuksiensa ansiosta M-teräksillä on pystytty pienentämään koneistuskustannuksia ja parantamaan kilpailukykyä. Viime vuosien aikana lastuavat terät ja työstökoneet ovat kuitenkin kehittyneet ja ero M-terästen ja tavanomaisten terästen välillä on voinut kaventua. Tämän diplomityön tavoitteena oli tutkia, saavutetaanko M-teräksen käytöllä taloudellisia etuja nykyaikaisissa konepajaolosuhteissa. Tutkimuksessa vertailtiin M-käsitellyn ja tavanomaisen 42CrMo4 – teräksen koneistusta. Valmistuskokeissa tarkasteltiin terien kulumista, lastun muotoa ja pinnanlaatua. Koekappaleena toimi olakkeellinen kuusiomutteri M64 kierteellä. Tuotteita valmistettiin yli 500 kappaletta ja materiaalia poistettiin noin 2000 kg. Koetulosten perusteella tuotteille laskettiin koneistuskustannukset kuvitteellisessa yrityksessä. Ero materiaalien välillä oli suurin työvaiheissa, joissa lastuaminen oli jatkuvaa. Sisä- ja ulkosorvauksessa M-käsiteltyä terästä lastunneiden terien kestoikä oli noin kaksinkertainen ja kierteen sorvauksessa noin nelinkertainen tavalliseen teräkseen verrattuna. Hakkaavassa työstössä terien kestoikä oli molemmilla materiaaleilla sama. Työssä suoritettujen kokeiden ja kustannuslaskelmien perusteella, käyttämällä M-käsiteltyä terästä voidaan pienentää valmistuskustannuksia. Materiaalien välinen ero korostuu, kun hakkaavaa työstöä on vähän, sarjat ovat suuria ja tuotanto on miehittämätöntä.

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Some material aspects such as grain size, purity and anisotropy exert an important influence on surface quality, especially in single point diamond turning. The aim of this paper is to present and discuss some critical factors that can limit the accuracy of ultraprecision machining of non-ferrous metals and to identify the effects of them on the cutting mechanism with single point diamond tools. This will be carried out through observations of machined surfaces and chips produced using optical and scanning electron microscopy. Solutions to reduce the influence of some of these limiting factors related with the mechanism of generation of mirror-like surfaces will be discussed.

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Numerical simulation of machining processes can be traced back to the early seventies when finite element models for continuous chip formation were proposed. The advent of fast computers and development of new techniques to model large plastic deformations have favoured machining simulation. Relevant aspects of finite element simulation of machining processes are discussed in this paper, such as solution methods, material models, thermo-mechanical coupling, friction models, chip separation and breakage strategies and meshing/re-meshing strategies.

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The aim of this work is to evaluate the mechanism of stock removal and the ground surface quality of advanced ceramics machined by a surface grinding process using diamond grinding wheels. The analysis of the grinding performance was done regarding the cutting surface wear behavior of the grinding wheel for ceramic workpieces. The ground surface was evaluated using Scanning Electron Microscopy (SEM). As a result it can be said that the mechanism of material removal in the grinding of ceramic is largely one of brittle fracture. The increase of the h max can reduce the tangential force required by the process. Although, it results in an increase in the surface damage, reducing the mechanical properties of the ground component.

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This paper discusses the effect of tool wear on surface finish in single-point diamond turning of single crystal silicon. The morphology and topography of the machined surface clearly show the type of cutting edge wear reproduced onto the cutting grooves. Scanning electron microscopy is used in order to correlate the cutting edge damage and microtopography features observed through atomic force microscopy. The possible wear mechanisms affecting tool performance and surface generation during cutting are also discussed. The zero degree rake angle single point diamond tool presented small nicks on the cutting edge. The negative rake angle tools presented more a type of crater wear on the rake face. No wear was detected on flank face of the diamond tools.