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KOOPHEZI-L: Pertsona kooperatiboaren profila langileetan neurtzeko eskala
Get PDF2017-2018. Ikasturtean Gipuzkoako Foru Aldundiaren “Gipuzkoan
pertsona eta enpresa partehartzaileak sustatzeko programa”-ren
laguntzaren bitartez, KOOPHEZI-i: Pertsona Kooperatiboaren Profila Gazteetan (16-22 urte bitartekoak) neurtzeko Eskala eraiki genuen. Proiektu honen iparra pertsona kooperatiboa identifikatzea eta garatzea izanik, eta 2018-2019 ikasturtean ipar berberari jarraituz, Erakundeek eta enpresek dituzten erronkei eta gizarte erronkei erantzuteko, Langilerian konpetentzia espezifikoak neurtzeko tresna psikometriko bat eraiki dugu
Partial Power Processing Based Charging Unit for Electric Vehicle Extreme Fast Charging Stations
Get PDFThis paper presents an analysis and design of a charging unit inside an electric vehicle extreme fast charging station. Due to the benefits that partial power processing achieves in terms of size reduction and efficiency improvement, it is decided to implement a partial power converter architecture. This type of architectures reduce the power to process by the converter but, they require an isolated topology. Therefore, a dual active bridge is selected for the study. Then, design wise, four different turns ratio values are selected and their performance results are compared in terms of processed power by the converter, semiconductors stress factor and energy loss. Finally, it is concluded that the turns ratio value is a key factor that must be correctly selected for optimizing the concerned comparison parameters
Experimental uncertainty decompositions of aerodynamic coefficients affected by operative condition variations
Get PDFA twofold analysis is performed on an experimental set-up comprising a low-Reynolds wind tunnel, with the aim of quantifying the effect of measurand uncertainties and operative condition variations in the lift and drag curves of a NACA0021 airfoil. The first part of the study focuses on an uncertainty analysis of basic measurands used for calculating standard aerodynamic magnitudes, showing the individual contributions of each of the factors affecting the overall uncertainty ranges. The second part intends to show how those uncertainties are propagated to lift and drag coefficients, and to calculate the effect of varying operative conditions on those curves. It is found that, when changes in operative conditions are left unattended, their influence on derived magnitudes may grow as large as to cause the resultant data to lie outside the estimated uncertainty intervals. Additionally, those variations are shown to depend non-linearly on the operative condition changes that produce them
Review of Architectures Based on Partial Power Processing for DC-DC Applications
Get PDFThis paper presents a review of advanced architectures based on the partial power processing concept, whose main objective is to achieve a reduction of the power processed by the converter. If the power processed by the converter is decreased, the power losses generated by the power converter are reduced, obtaining lower sized converters and higher system efficiencies. Through the review 3 different partial power processing strategies are distinguished: Differential Power Converters, Partial Power Converters and Mixed strategies. Each strategy is subdivided into smaller groups that entail different architectures with their own advantages and disadvantages. Also, due to the lack of agreement that exists in the sources around the naming of the different architectures, this paper seeks to stablish a nomenclature that avoids confusion when indexing this type of architectures. Regarding Partial Power Converters an extensive application oriented description is also developed. Finally, the main conclusions obtained through the review are presented
Recycling in Babel: The Impact of Foreign Languages in Rule Learning
Get PDFEnvironmental decisions and prosocial behaviors have been shown to be emotionally mediated, and language is at the core of emotions. The language context can alter the way decisions are made, and using a foreign language tends to favor an analytic approach to the decision and reduce its emotional resonance. In the present work, we explored whether or not the strategic use of a native vs. a non-native language could alter the learning of rules that are at the basis of our environmental behavior. To test this, elementary school students carried out a series of tasks that required recycling the employed materials at the end of the session. Children had to put each kind of material used in the corresponding container following basic association rules, resembling the process that they would do at home when recycling. Some students received the whole set of instructions and rules in their native language, while others received them in their foreign language. When the recycling behaviors were compared, results showed that participants who were instructed in their non-native language followed the rules better than their natively instructed peers. These results are discussed in the light of different perspectives, and future directions in the strategic use of language contexts are considered
Modelling of an Additive 3D-Printing Process Based on Design of Experiments Methodology
Get PDFPurpose: The implementation of additive manufacturing (AM) or 3D-printer manufacturing for technical prototyping, preproduction series and short production series can bring benefits in terms of reducing cost and time to market in product development. These technologies are beginning to be applied in different industrial sectors and have a great possibility of development. As these technologies are still in development, there is a need to define the capacity of the 3D machines to establish minimum standards for producing high-quality parts.
Methodology/Approach: The proposed methodology is based on a design of experiments (DOE) approach, which serves as a guide for engineers when it comes to executing any experimental study. The following steps were followed (Unzueta et al., 2019): Phase 1: define; Phase 2: measure; Phase 3: plan; Phase 4: execute experimentation; Phase 5: analyse the results; Phase 6: improve via confirmation experiments; Phases 7-8: control and standardise.
Findings: The proposed methodology is based on a design of experiments (DOE) approach, which serves as a guide for engineers when it comes to executing any experimental study. The following steps were followed (Unzueta et al., 2019): Phase 1: define; Phase 2: measure; Phase 3: plan; Phase 4: execute experimentation; Phase 5: analyse the results; Phase 6: improve via confirmation experiments; Phases 7-8: control and standardise.
Originality/Value of paper: This study uses a methodological approach to demonstrate how the 3D printing technology can be enriched with statistical testing techniques (DOE). It defines numerical prediction models to obtain high-quality parts with a new AM technology, using a planning process with a minimum amount of experimentation
Lanki kuadernoak = Cuadernos Lanki ; 14
No full textLANKI-k, Mondragon Unibertsitateko kooperatibismoaren ikertegiak, Kataluniako proiektu sozioenpresarial bati buruzko kasu azterketa aurkezten du; zehazki, Fagedari buruzkoa.
Oso proiektu berezia da, desgaitasun psikikoak eta buruko gaixotasunak dituzten pertsonek
osatzen baitute. Proiektuaren helburua pertsona horien bizi-baldintzak eraldatzea da, eta, horretarako, kooperatiba bat sortu dute. Fagedak ezinezkoa zirudiena errealitate bihurtu du; hau da, Garrotxa eskualdean urritasun psikikoak dituzten pertsona guztiek lana izatea eta arreta terapeutikoa
jasotzea; gainera, gaur egun Kataluniako jogurt-marka salduena da (langileen ezaugarriei buruzko
publizitatea egin gabe lortu dute hori, beren lehiakortasuna produktuen kalitatean oinarrituz).
Fageda utopia bat ari da egikaritzen praktikan (bere ekarpen, zailtasun eta kontraesanekin). Proiektuaren ezaugarri interesgarriena da helburu sozial eta humanoari ematen dion zentraltasuna; gako
horrek azaltzen du zergatik garatu duten enpresa egiteko modu berezia. Esperientzia inspiratzailea
da, eta berau aztertzea baliagarria izan zaigu kooperatibismoaren balioak gogora ekartzeko, gaur
egungo eredu kooperatiboa nola hobetu hausnartzeko eta norantz joan nahi genukeen irudikatzeko. Mondragoneko kooperatibismoak etorkizunera begiratu behar du, logika kooperatiboak
etengabe sakondu eta berrasmatu. Funtsean, bidai hori egiteko bidelaguna aurkitu dugu
Analysis and Design Guidelines for Current Control Loops of Grid-Connected Converters Based on Mathematical Models
Get PDFHaving a method for analyzing and designing regulators of controls that contain many current loops such as active filters is not a trivial task. There can be many parameters of regulators and filters that must be carefully selected in order to fulfill certain desired requirements. For instance, these can be stability, dynamic response, robustness under uncertainty of parameters, and rejection capability to switching harmonics. Hence, this paper provides general analysis guidelines for designing current control loops by using mathematical models in an αβ reference frame. Then, by using the proposed modeling tool, a multi-objective tuning algorithm is proposed that helps obtain all the control loops’ regulator and filter parameters, meeting all the desired requirements. Thus, the proposed analysis and design methodology is illustrated by applying it to three different controls conceived in a dq rotating reference frame with PI (Proportional Integral) regulators. The first control presents two current loops (simple dq current control), the second control uses four current loops (dual vector control, for unbalanced loads), while the third control presents eight current loops (active filter controlling current harmonics). Several experimental and simulation results show the effectiveness and usefulness of the proposed method. Since the mathematical model employed is in the αβ reference frame, it can also be easily applied to controls conceived in a αβ reference frame using resonant regulators, providing also a common comparative framework
Preliminary Study on the Capability of the Novel Near Solidus Forming (NSF) Technology to Manufacture Complex Steel Components
Get PDFThe benefits of the novel Near Solidus Forming (NSF) process has shown previously in its ability to produce steel components with comparable as-forged mechanical properties but with a cost reduction of 10–15%. This study further pushes the NSF technology to produce parts that are conventionally diffcult to produce via conventional methods. A 2.7 kg 42CrMo4 steel grade component was manufactured into a complex geometry using only a 400t press.
Different manufacturing parameters were evaluated to show their influence on the process and final component. A combination of X-ray fluorescence (XRF), optical microscopy and SEM analysis of the microstructure was also conducted revealing the deformation pattern of the material and shedding some light on how the material evolves during the process. The successful forging of these components shows the capability to produce previously deemed diffcult geometries, with much a
lower specification forging press, in a single deformation