909 resultados para transfer suction box
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In this article, a methodology is used for the simultaneous determination of the effective diffusivity and the convective mass transfer coefficient in porous solids, which can be considered as an infinite cylinder during drying. Two models are used for optimization and drying simulation: model 1 (constant volume and diffusivity, with equilibrium boundary condition), and model 2 (constant volume and diffusivity with convective boundary condition). Optimization algorithms based on the inverse method were coupled to the analytical solutions, and these solutions can be adjusted to experimental data of the drying kinetics. An application of optimization methodology was made to describe the drying kinetics of whole bananas, using experimental data available in the literature. The statistical indicators enable to affirm that the solution of diffusion equation with convective boundary condition generates results superior than those with the equilibrium boundary condition.
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The transposition of the São Francisco River is considered one of the greatest engineering works in Brazil of all time since it will cross an extensive agricultural region of continental dimensions, involving environmental impacts, water, soil, irrigation, water payment and other multidisciplinary themes. Taking into account its importance, this subject was incorporated into a discipline of UFSCar (Federal University of São Carlos - Brazil) named "Pollution and Environmental Impacts". It was noted strong reaction against the project, even before the presentation. To allow a critical analysis, the first objective was to compile the main technical data and environmental impacts. The second objective was to detect the three most important aspects that cause reaction, concluding for the following reasons: assumption that the volume of water to be transferred was much greater than it actually is proposed in the project; lack of knowledge about similar project already done in Brazil; the idea that the artificial canal to be built was much broader than that proposed by the project. The participants' opinion about "volume to be transferred" was raised quantitatively four times: 2-undergraduate students; 1-graduate; 1-outside community. The average resulted 14 times larger than that proposed in the project, significant according to t-test. It was concluded that the reaction to water transfer project is due in part to the ignorance combined with a preconceived idea that tend to overestimate the magnitude of environmental impacts.
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The focus of the present work was on 10- to 12-year-old elementary school students’ conceptual learning outcomes in science in two specific inquiry-learning environments, laboratory and simulation. The main aim was to examine if it would be more beneficial to combine than contrast simulation and laboratory activities in science teaching. It was argued that the status quo where laboratories and simulations are seen as alternative or competing methods in science teaching is hardly an optimal solution to promote students’ learning and understanding in various science domains. It was hypothesized that it would make more sense and be more productive to combine laboratories and simulations. Several explanations and examples were provided to back up the hypothesis. In order to test whether learning with the combination of laboratory and simulation activities can result in better conceptual understanding in science than learning with laboratory or simulation activities alone, two experiments were conducted in the domain of electricity. In these experiments students constructed and studied electrical circuits in three different learning environments: laboratory (real circuits), simulation (virtual circuits), and simulation-laboratory combination (real and virtual circuits were used simultaneously). In order to measure and compare how these environments affected students’ conceptual understanding of circuits, a subject knowledge assessment questionnaire was administered before and after the experimentation. The results of the experiments were presented in four empirical studies. Three of the studies focused on learning outcomes between the conditions and one on learning processes. Study I analyzed learning outcomes from experiment I. The aim of the study was to investigate if it would be more beneficial to combine simulation and laboratory activities than to use them separately in teaching the concepts of simple electricity. Matched-trios were created based on the pre-test results of 66 elementary school students and divided randomly into a laboratory (real circuits), simulation (virtual circuits) and simulation-laboratory combination (real and virtual circuits simultaneously) conditions. In each condition students had 90 minutes to construct and study various circuits. The results showed that studying electrical circuits in the simulation–laboratory combination environment improved students’ conceptual understanding more than studying circuits in simulation and laboratory environments alone. Although there were no statistical differences between simulation and laboratory environments, the learning effect was more pronounced in the simulation condition where the students made clear progress during the intervention, whereas in the laboratory condition students’ conceptual understanding remained at an elementary level after the intervention. Study II analyzed learning outcomes from experiment II. The aim of the study was to investigate if and how learning outcomes in simulation and simulation-laboratory combination environments are mediated by implicit (only procedural guidance) and explicit (more structure and guidance for the discovery process) instruction in the context of simple DC circuits. Matched-quartets were created based on the pre-test results of 50 elementary school students and divided randomly into a simulation implicit (SI), simulation explicit (SE), combination implicit (CI) and combination explicit (CE) conditions. The results showed that when the students were working with the simulation alone, they were able to gain significantly greater amount of subject knowledge when they received metacognitive support (explicit instruction; SE) for the discovery process than when they received only procedural guidance (implicit instruction: SI). However, this additional scaffolding was not enough to reach the level of the students in the combination environment (CI and CE). A surprising finding in Study II was that instructional support had a different effect in the combination environment than in the simulation environment. In the combination environment explicit instruction (CE) did not seem to elicit much additional gain for students’ understanding of electric circuits compared to implicit instruction (CI). Instead, explicit instruction slowed down the inquiry process substantially in the combination environment. Study III analyzed from video data learning processes of those 50 students that participated in experiment II (cf. Study II above). The focus was on three specific learning processes: cognitive conflicts, self-explanations, and analogical encodings. The aim of the study was to find out possible explanations for the success of the combination condition in Experiments I and II. The video data provided clear evidence about the benefits of studying with the real and virtual circuits simultaneously (the combination conditions). Mostly the representations complemented each other, that is, one representation helped students to interpret and understand the outcomes they received from the other representation. However, there were also instances in which analogical encoding took place, that is, situations in which the slightly discrepant results between the representations ‘forced’ students to focus on those features that could be generalised across the two representations. No statistical differences were found in the amount of experienced cognitive conflicts and self-explanations between simulation and combination conditions, though in self-explanations there was a nascent trend in favour of the combination. There was also a clear tendency suggesting that explicit guidance increased the amount of self-explanations. Overall, the amount of cognitive conflicts and self-explanations was very low. The aim of the Study IV was twofold: the main aim was to provide an aggregated overview of the learning outcomes of experiments I and II; the secondary aim was to explore the relationship between the learning environments and students’ prior domain knowledge (low and high) in the experiments. Aggregated results of experiments I & II showed that on average, 91% of the students in the combination environment scored above the average of the laboratory environment, and 76% of them scored also above the average of the simulation environment. Seventy percent of the students in the simulation environment scored above the average of the laboratory environment. The results further showed that overall students seemed to benefit from combining simulations and laboratories regardless of their level of prior knowledge, that is, students with either low or high prior knowledge who studied circuits in the combination environment outperformed their counterparts who studied in the laboratory or simulation environment alone. The effect seemed to be slightly bigger among the students with low prior knowledge. However, more detailed inspection of the results showed that there were considerable differences between the experiments regarding how students with low and high prior knowledge benefitted from the combination: in Experiment I, especially students with low prior knowledge benefitted from the combination as compared to those students that used only the simulation, whereas in Experiment II, only students with high prior knowledge seemed to benefit from the combination relative to the simulation group. Regarding the differences between simulation and laboratory groups, the benefits of using a simulation seemed to be slightly higher among students with high prior knowledge. The results of the four empirical studies support the hypothesis concerning the benefits of using simulation along with laboratory activities to promote students’ conceptual understanding of electricity. It can be concluded that when teaching students about electricity, the students can gain better understanding when they have an opportunity to use the simulation and the real circuits in parallel than if they have only the real circuits or only a computer simulation available, even when the use of the simulation is supported with the explicit instruction. The outcomes of the empirical studies can be considered as the first unambiguous evidence on the (additional) benefits of combining laboratory and simulation activities in science education as compared to learning with laboratories and simulations alone.
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The ability of a multinational company to effectively transfer knowledge from one unit to another can create a great source of competitive advantage and is crucial for long-term success. However, in their attempts to disseminate existent knowledge across national boundaries, organizations encounter several obstacles. Especially challenging is the transfer of tacit knowledge, the most valuable kind, as it is embedded in the minds and the behavior of people. The purpose of this study is to identify the main factors and challenges to be considered in intra-organizational knowledge transfer and consequently develop a framework that could be utilized to improve the process. The research is of qualitative nature and it adopts an exploratory approach. The study was further conducted as an intensive single-case study through studying a Finnish multinational company, and the researcher adopted a role as a participant observant in the research setting. Other data collection methods include semi-structured interviews and an online survey. The research findings show that knowledge transfer is currently challenging within the international sales organization of the case company. The majority of knowledge is currently concentrated in the company headquarters, and it is not always systematically distributed to the regional offices abroad. The main factor affecting knowledge transfer seems to be the organizational culture, which does not support or encourage knowledge sharing. The company is struggling in having a common place for information and employees that lack proper social networks have difficulties accessing relevant knowledge. Some recommended improvement suggestions include the institutionalization of knowledge transfer by turning it into an articulated organizational goal, and the implementation of a reward system that includes soft factors, such as teamwork and knowledge sharing behavior. Furthermore, the organizational culture should be more open and supportive in order to reinforce trust. Individuals in regional offices should be given better support by offering them dedicated mentors and increasing the amount of expatriation. Finally, knowledge should actively be codified and stored in commonly shared platforms where it is easily accessible by all employees.
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Liiketoimintaa tukevien palvelujen etätuotanto edustaa uutta kansainvälistymisen muotoa. Kehittyvien markkinoiden nousu yhdistettynä yritysten arvoketjutoimintojen kansainvälistymiseen on luonut yrityksille kasvavan paineen etsiä parasta sijaintia toiminnoilleen. Monikansalliset yritykset ovat yhä useammin korvanneet paikallisia henkilöstöpalvelujaan siirtymällä globaaliin malliin jaettujen palvelujen tuotannossa. Tämä diplomityö on toteutettu tukeakseen UPM:n henkilöstöhallintoa globaalin palvelukeskuksen perustamisessa Puolaan. Tutkimuksen tavoitteena on laajentaa käsitystä henkilöstöpalvelujen tarjontamallin uudistamiseen johtaneista tekijöistä ja motiiveista. Empiirisen tutkimuksen tärkein tavoite on tukea rekrytoinnin hallinnollisten töiden siirtoa globaaliin palvelukeskukseen palvelun laadun säilyessä vähintään aikaisemmalla tasolla. Tutkimuksen tulokset painottavat strategista näkökulmaa muutokseen. Strategiset syyt UPM:n henkilöstöhallinnon globaalin palvelukeskuksen perustamiselle sisältävät ylikapasiteetin ja päällekkäisten toimintojen vähentämisen eri maissa. Muutos lisää palvelun joustavuutta sekä edesauttaa toiminnan läpinäkyvyyttä, ennustettavuutta ja kustannusten valvontaa. Onnistuneesti toteutetut jaetut palvelut voivat toimia hyvänä lähtökohtana tehokkaiden henkilöstöpalvelujen tuottamiselle.
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Tässä väitöskirjassa tarkastellaan suurnopeustekniikan eri sovelluksissa ilmeneviä roottoreihin liittyviä rakenteellisia vaatimuksia ja haasteita. Tässä yhteydessä suurnopeustekniikalla tarkoitetaan järjestelyä, jossa sähkökone (moottori, generaattori) ja toimilaite (turbiini, kompressori, puhallin) on kytketty ilman vaihdetta suoraan mekaanisesti yhteen ja jossa yhteisen roottorin pyörimisnopeus on selvästi suurempi kuin 50/60 hertsin verkosta syötetyn kaksinapaisen vaihtovirtasähkökoneen tahtinopeus. Tyypillistä suurnopeuskoneen roottorille on suuri tehotiheys ja suuri mekaaninen kuormitus. Siksi esimerkiksi sähkökoneen jäähdytys on entistä haasteellisempaa kasvavien rautahäviöiden ja pienempien lämmönsiirtopinta-alojen vuoksi. Tämän työn tavoitteet voidaan jakaa kolmeen osaan: Yhdistetyn sähkö- ja turbokoneen roottorin mekaanisen rakenteen tarkastelu, jonka tavoitteena on pienentää lämmönkehitystä ja tehostaa kriittisten kohtien jäähdytystä. Tähän liittyy sähkömagneettisten häviöiden keskittäminen jäähdytyksen kannalta edullisiin kohtiin Yhdistetyn sähkö- ja turbokoneen roottorin mekaanisen rakenteen tarkastelu kriittisten ominaistaajuuksien kannalta Yhdistetyn sähkö- ja turbokoneen roottorin mekaanisen rakenteen analysointi lujuustekniseltä kannalta. Tähän liittyvät mm. erilaiset ahdistussovitteet ja niiden säilyminen korkeilla pyörimisnopeuksilla sekä niiden roottoria jäykistävä vaikutus ja lämmön johtuminen kyseisissä liitospinnoissa. Tämän työn tieteellinen uutuusarvo on nimenomaan yhdistetyn sähkö- ja turbokoneen roottorin rakenteen analysointi ottamalla samanaikaisesti huomioon kaikki edellä mainitut näkökohdat: jäähtyminen erityisen kuumissa kohdissa, sähköisten häviöiden alentaminen ja niiden jakautuman huomioon ottaminen, roottorin jäykkyyden maksimointi, lujuusrasitusten hallinta ja rakenteen mekaaninen stabiliteetti sekä lämpöteknisten ylimenovastusten tarkastelu.
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Following over 170+ pages and additional appendixes are formed based on content of Course: Fundamentals of Heat Transfer. Mainly this summarizes relevant parts on Book of Fundamentals of Heat and Mass Transfer (Incropera), but also other references introducing the same concepts are included. Student’s point of view has been consideredwith following highlights: (1) Relevant topics are presented in a nutshell to provide fast digestion of principles of heat transfer. (2) Appendixes include terminology dictionary. (3) Totally 22 illustrating examples are connecting theory to practical applications and quantifying heat transfer to understandable forms as: temperatures, heat transfer rates, heat fluxes, resistances and etc. (4) Most important Learning outcomes are presented for each topic separately. The Book, Fundamentals of Heat and Mass Transfer (Incropera), is certainly recommended for those going beyond basic knowledge of heat transfer. Lecture Notes consists of four primary content-wise objectives: (1) Give understanding to physical mechanisms of heat transfer, (2)Present basic concepts and terminology relevant for conduction, convection and radiation (3) Introduce thermal performance analysis methods for steady state and transient conduction systems. (4) Provide fast-to-digest phenomenological understanding required for basic design of thermal models
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The ability to share knowledge efficiently is vital in day-to-day operations of multinational companies. Therefore, the tools for the effective knowledge sharing along with the transfer knowledge models are of a primary interest for the companies. Knowledge transfer often involves participants of different cultural background. The purpose of this research is to investigate how the cross-cultural knowledge transfer in a multinational corporation takes place and how the successful knowledge transfer is ensured. The four sub-questions will help to answer the research question. Firstly, the author will try to identify what difficulties might occur while transferring knowledge in a multicultural environment. Secondly, the cultural differences’ impact on cross-cultural communication will be explored. Thirdly, the tools and models for effective tacit knowledge transfer will be covered by the author. Lastly, the methods of assessing if a knowledge transfer was successful or not will be discussed. The focus of this thesis is on knowledge transfer within a multinational setting. A multinational corporation is used as a practical example for this study; namely the Training Centre of the multinational corporation. The study was carried out by using a qualitative research approach. The four employees of the Training Centre were interviewed in order to obtain the answers to the research questions. The complete idea of the data gathering process can be obtained by reading through the first part of the methodology section Furthermore, the matters of transferability, confirmability, trustworthiness and objectivity were discussed in the methodological section. The study indicates that in order to carry out the successful and efficient knowledge transfer several requests have to be met. Mutual motivation, e.g. the motivation of both knowledge sender and knowledge receiver is one of the most important determinants of knowledge transfer. Sufficient and bearable workload for the knowledge senders is important to ensure the quality and involvement of the knowledge sender into knowledge transfer process. Course contents, infrastructure and other matters will be discussed further on in relation of successful knowledge transfer. Influences of cultural differences on knowledge sharing were studied in this thesis. At the end of the empirical study- a model used to transfer knowledge in Training Centre will be presented. The model created proves to be functional and appropriate for transferring knowledge to representatives of different cultures.
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Knowledge transfer is a complex process. Knowledge transfer in the form of exporting education products from one system of education to another is particularly complicated, because each system has been developed in a particular context to meet the requirements seen as relevant at each time. National innovation systems are often seen to form an essential framework within which the development of a country, its economy and level of knowledge are considered and promoted. These systems are orientated towards the future, and as such they also provide a framework for the knowledge transfer related to the development of education. In the best of circumstances they are able to facilitate and boost this transfer both from the viewpoint of the provider and the recipient. The leading thought and the idea of the study is that education export is a form of knowledge transfer, which is illustrated by the existing models included. The purpose of this study is to explore, analyze and describe the factors and phenomena related to education export, and more specifically, those related to the experiences and potential of Finnish education export to Chile. For better understanding, of the multiplicity of the issue involved, the current status of education export between Finland and Chile and he existing efforts within the Finnish innovation network will be outlined as well as new forms of co-operation between Finland and Chile in educational matters explored. Several countries have started to commercialize their education system in order to establish themselves as emerging education exporters. Moreover, the demand for education reform is accurate in many developing countries. This offers a good match between Finland and Chile to be the example countries of the research. The main research findings suggest that there are several business areas in education export. These include degrees in education, training services and education technologies for example The factors that influence education export can be divided into four groups, including academic, cultural, political and economic aspects. Challenges to overcome include the lack of product or services to be sold, lack of market and cultural knowledge of the buyer country, financing and lack of suitable pricing model. National innovation systems could be seen as enabling entities for successful education export. The extensive networks that national innovation systems aim to form, could operate as a basis for joining the forces in selling knowledge as well as receiving knowledge in a constructive way.
Biophysical modeling of photosynthetic electron transfer and practical applications to cyanobacteria
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In this thesis, the DFMA is presented and used for the purpose of having a design for a vertical transfer line that can be easily manufactured and assembled. The design of the transfer line, the major components and drawings are presented. The ease of assembly, the costs of manufacturing and differences between the use of steel structure and aluminum are compared. The ALARA principle is followed to minimize the risk of radiation exposure by the means of locating the test ion sources outside the radioactive area.
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Lipider är viktiga biomolekyler, eftersom de bygger upp alla cellulära membran. Glykolipider, dvs. lipider som innehåller socker, är dessutom betydelsefulla som signaleringsmolekyler vid olika processer. Det är essentiellt att regleringen av syntesen, nedbrytningen samt transporten av lipider i cellen är noggrant koordinerade, och faktorer som kan påverka lipidmetabolismen är därför viktiga att undersöka. Denna avhandling har undersökt två olika lipidbindande proteiner, glykolipidtransportprotein (GLTP) och ceramidtransportprotein (CERT). GLTPs biologiska funktion är ännu oklar, dock vet man att GLTP har förmåga att binda olika glykolipider samt överföra dessa lipider mellan olika lipidmembraner. CERT har däremot visats kunna transportera ceramid från det endoplastiska retiklet (ER) till Golgi-apparaten, för produktion av sfingomyelin. I detta avhandlingsarbete undersöktes lokaliseringen av GLTP i celler med olika metoder, bl.a. konfokalmikroskopi, samt olika centrifugeringsmetoder. Genom att överuttrycka GLTP i celler och därefter analysera halten nysyntetiserade glykolipider, kunde även sambandet mellan GLTP-uttrycket och dessa lipider undersökas. I avhandlingen identifierades ytterligare en specifik aminosyrasekvens hos GLTP. Denna sekvens visades kunna binda till VAP-A, ett integralt ER protein, med en tidigare fastställd viktig funktion vid regleringen av lipidtransporten. I avhandlingen analyserades även hur ceramidtransporten mellan två olika membraner, medierad av CERT, påverkas av egenskaper i ceramidens omgivning. För att undersöka detta användes artificiella modellmembraner samt fluorimetriska metoder. Sammansättningen och packningen hos lipidmembranerna visades ha en stor betydelse för den CERT-katalyserade ceramidtransporten. Sammanfattningsvis antyder resultaten från avhandlingen att det existerar flera faktorer som kan påverka aktiviteten av GLTP och CERT, vilka i sin tur har förmåga att reglera lipidmetabolismen.
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Passive immunity transfer (PIT) evaluation is an essential tool for the maintenance of healthy calves during the first months of life. Since lactation number and breed have been proven to influence immunoglobulin levels in colostrum, the aim of this study was to evaluate PIT from primiparous and multiparous Canchim cows to their calves. Blood samples were collected from the calves before colostrum intake and 1, 2, 7, 15 and 30 days thereafter, while colostrum samples from the cows were taken immediately after parturition. Activities of gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), and concentrations of total protein, albumin, globulins, immunoglobulin A (IgA), immunoglobulin G (IgG), total and ionized calcium, inorganic phosphorus, magnesium, sodium and potassium were evaluated in calves' serum and activities of GGT and ALP and concentrations of total protein, IgA and IgG were assessed in cow's colostrum whey. Immunoglobulins concentrations were evaluated by electrophoresis in polyacrylamide gels. Serum biochemistry evaluations revealed an increase in gamma-glutamyl transferase and alkaline phosphatase activities and in total protein, globulins, immunoglobulin A and immunoglobulin G levels in calves' serum after colostrum intake. Only total protein and light chain immunoglobulin G levels in colostrum whey were affected by the cows' lactation number. Phosphorus and magnesium levels in blood serum increased after colostrum intake, while sodium and potassium levels oscillated in the experimental period. PIT was influenced by the cows' lactation number but was efficient in both groups.
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The objective of this study was to evaluate and compare the transfer of passive immunity and the proteinogram in Criollo Lageano (CL) and Black and White Holstein (BWH) calves. Two groups were utilized with 13 Criollo Lageano and 10 BWH calves. Blood samples were collected for the measurement of total serum protein, electrophoresis of serum proteins, activity of the gamma glutamyl transferase, and concentration of IgG by the method of the zinc sulfate turbidity in periods between 24 and 36 hours of life, 15, 30, 60, 90, 120, 150 and 180 days. Statistical analysis was performed by ANOVA and Tukey test at 5% significance level, and correlations between variables were calculated. Variations of serum proteins followed a pattern of physiological behavior over the first six months of life and production of immunoglobulins was active earlier in BWH calves and slower in the Criollo Lageano, without causing any impact on their health. Gamma globulin in the first days of life (24-36h) was correlated with IgG (r=0.87 for CL and r=0.89 for BWH), PTS (r=0.91 for CL and r=0.92 for BWH), Glob (r=0.99 for CL and r=0.98 for BWH) and GGT (r=0.14 for CL and r=0.83 for BWH). It was concluded that there was no failure in the transfer of passive immunity in Criollo Lageano calves but this failure occurred in the BWH calves. IgG values estimated by the zinc sulfate turbidity and serum proteins were considered good indicators of the transfer of passive immunity in calves between 24 and 36 hours of life.