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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Conception et réalisation d'un microsystème pour la mesure d'encrassement organique, minéral et biologique dans les procédés - : intégration des régimes thermiques périodiques. / Microsystem conception and realisation to monitor organic, mineral and biologic fouling in processes : integration of periodic thermal regime

Crattelet, Jonathan 17 December 2010 (has links)
Dans les industries de procédés, les opérations de pompage et de transformation sont fondamentales et omniprésentes. Durant ces opérations unitaires (incluant des transferts de chaleur, de matière et de quantités de mouvement), les produits évoluent (réactions chimiques et biochimiques, croissances microbiennes, traitements thermiques, etc.) induisant dans de nombreux cas des phénomènes d'encrassement avec des cinétiques et des intensités variables. Les recherches issues de l’INRA ont conduit à la mise au point d’un capteur d’encrassement basé sur une analyse thermique différentielle et locale. Ce dernier permet le contrôle en continu et en ligne du niveau d’encrassement d’un équipement et a été protégé par brevet. L’entreprise Neosens a acquis une licence d’exploitation exclusive sur ce brevet afin de développer et commercialiser le produit dont les limites sont maintenant connues.Dans ce travail, nous visons à atteindre deux objectifs majeurs en vue de répondre aux nouvelles problématiques posées. Le premier doit permettre la mise au jour d’un capteur d’encrassement en utilisant les technologies microsystèmes. Le second vise la validation d’un nouveau mode de fonctionnement et d’une méthode pour le contrôle de l’encrassement. Ce travail s'appuie naturellement sur les travaux antérieurs et les principales phases de recherche ont porté sur la conception, la réalisation et l'intégration d'éléments sensibles sur les bases technologiques des microsystèmes, l'intégration des régimes thermiques permanent et périodique associés au traitement en ligne du signal et à la validation expérimentale aux échelles laboratoire, pilote et industrielles des géométries et configurations nouvelles.Les travaux de recherche ont permis de fiabiliser et d’améliorer considérablement les performances métrologiques. Le microsystème réalisé apparaît comme complémentaire du capteur existant en termes de limites de détection et de quantification. / In industrial processes including agro and bioprocess, fouling is considered to be a complex and misunderstood phenomenon. Unit operations (including heat, mass and momentum transfers) are carried out in continuous, batch or fed-batch processes. During these operations, the products may evolve (chemical and biochemical reactions, microorganisms growth and activity, etc.) and fouling may occur with a wide range of kinetics from minutes up to years and dimensions from micrometers up to centimeters. Research issued from INRA led to develop a fouling sensor based on local differential thermal analysis and to patent this system. The device enables on-line and continuous monitoring of fouling propensity. Neosens company acquired an exclusive licence and develop and commercialize the sensor whose operating limits are known. In this work, our scientific and technological objectives are to break new locks through: (i) the realization of a fouling sensor based on microsystems technologies, (ii) the investigation and validation of an alternative thermal working mode and a method for fouling monitoring. Based on the previous work, our research deals with conception, realisation and integration of components based on microsystems technologies, integration of permanent and periodic thermal regimes with on-line data treatment and experimental validation at laboratory, pilot-plant and industrial scales for new geometries and configurations.This work led to metrology improvement and reliability. The resulting microsensor seems to be a complement of previous sensor regarding detection and quantification limits
42

Single and multi-antenna MC-DS-CDMA with joint detection for broadband block-fading channels

Basilio, Daniel Jorge 23 August 2010 (has links)
In the context of broadband wireless communications using code division multiple access (CDMA), the main multiple access (MA) options include single-carrier direct sequence CDMA (SC-DS-CDMA) using time-domain direct sequence spreading [1, p. 728], multicarrier CDMA (MC-CDMA) using frequency-domain spreading [2, 3] and multicarrier DS-CDMA (MC-DS-CDMA) using time-domain direct sequence spreading of the individual sub-carrier signals [4, 5]. It was shown in [6] that MC-DS-CDMA has the highest degrees of freedom in the family of CDMA schemes that can be beneficially exploited during the system design and reconfiguration procedures. An amalgam of MC-CDMA and MC-DS-CDMA known as time and frequency domain spreading (TF-domain spreading) MC-DS-CDMA was proposed in [6]. TF-domain spreading MC-DS-CDMA has several benefits over conventional MC-DS-CDMA with regard to both capacity and performance [7]. However, in contrast to conventional MC-DS-CDMA, TF-domain spreading MC-DS-CDMA introduces MUI, which necessitates the use of joint detection at the receiver. Recently, multiple input multiple output (MIMO) or multi-antenna TF-domain spreading MC-DS-CDMA schemes have been proposed in the literature that e ciently exploit both the spatial and frequency diversity available in MIMO frequency-selective channels [8, 9]. Although an extensive amount of research has been done on single and multi-antenna TF-domain spreading MC-DS-CDMA schemes that achieve both spatial and frequency diversity in frequency-selective slow fading channels [6–9], very little research considers the time-selectivity of the wireless channels encountered. Thus, the above-mentioned schemes may not be su ciently e cient, when communicating over wireless channels exhibiting both frequency-selective and time-selective fading. There are very few MC-DS-CDMA schemes in the literature that consider the time-selectivity of the wireless channels encountered. This study considers the design of single and multi-antenna TF-domain spreading MC-DS-CDMA, for frequency-selective block-fading channels, which are capable of exploiting the full diversity available in the channel (i.e. spatial, frequency and temporal diversity), using various methods of joint detection at the receiver. It has been shown that the diversity gain in block-fading channels can be improved by coding across multiple fading blocks [10–12]. Single-antenna TF-domain spreading MC-DS-CDMA is considered for the quasi-synchronous uplink channel, and multi-antenna TF-domain spreading MC-DS-CDMA is considered for the synchronous downlink channel. Numerous simulated bit error rate (BER) performance curves, obtained using a triply selective MIMO channel platform, are presented in this study using optimal and sub-optimal joint detection algorithms at the receiver. In addition, this study investigates the impact of spatial correlation on the BER performance of the MC-DS-CDMA schemes considered. From these simulated results, one is able to conclude that TF-domain spreading MC-DS-CDMA designed for frequency-selective block-fading channels performs better than previously proposed schemes designed for frequency-selective slow fading channels, owing to the additional temporal diversity exploited under the block-fading assumption. AFRIKAANS : In die konteks van bre¨eband- draadlose kommunikasie deur die gebruik van kodeverdelingveelvuldige toegang (KVVT) behels die belangrikste veelvuldigetoegang- (VT) opsies enkel-draer direkte-sekwensie KVVT (ED-DS-KVVT), deur die gebruik van tyd-domein direkte sekwensie-verspreiding [1, p. 728], veelvuldigedraer-KVVT (VD-KVVT) deur die gebruik van frekwensiedomein-verspreiding [2, 3] en VD-DS- KVVT deur die gebruik van tyd-domein direkte sekwensie-verspreiding van die individuele sub-draerseine [4, 5]. Daar is in [6] aangetoon dat VD-DS-KVVT die hoogste vlakke van vryheid in die familie KVVT-skemas het wat voordelig benut kan word gedurende sisteemontwerp en rekonfigurasieprosedures. ’n Amalgaam van VD-KVVT en VD-DS-KVVT bekend as tyd-en-frekwensiedomeinverspreiding (TF-domeinverspreiding) VD-DS-KVVT is voorgestel in [6]. TF-domeinverspreiding VD-DS-KVVT het verskeie voordele bo konvensionele VD-DS-KVVT wat sowel kapasiteit as werkverrigting betref [7]. In teenstelling met konvensionele VD-DS-KVVT benut TF-domeinverspreiding VD-DS-KVVT multi-gebruiker-interferensie, wat die gebruik van gesamentlike opsporing by die ontvanger noodsaak. In die onlangse verlede is in die literatuur veelvuldige-inset-veelvuldige-uitset- (VIVU) of veelvuldige-antenna TF-omeinverspreiding VD-DS-KVVT-skemas voorgestel wat sowel die ruimtelike as frekwensiediversiteit wat in VIVU frekwensie-selektiewe kanale beskikbaar is, e ektief gebruik [8, 9]. Hoewel uitgebreide navorsing onderneem is oor enkel- en multi-antenna TF-domeinverspreiding VD-DS-KVVT-skemas wat sowel ruimtelike as frekwensie diversiteit in frekwensie-selektiewe stadig deinende kanale bereik [6–9], oorweeg baie min navorsing die tyd-selektiwiteit van die draadlose kanale wat betrokke is. Bogenoemde skemas mag dus nie e ektief genoeg wees nie wanneer kommunikasie plaasvind oor draadlose kanale wat sowel frekwensie-selektiewe as tyd-selektiewe wegsterwing toon. Baie min VD-DS-KVVT-skemas in die literatuur skenk aandag aan die tyd-selektiwiteit van die betrokke draadlose kanale. Die studie ondersoek die ontwerp van enkel- en multi-antenna TF-domeinverspreiding VD-DS-KVVT vir frekwensie-selektiewe blokwegsterwingkanale, wat in staat is om die volle diversiteit wat in die kanaal beskikbaar is, te benut (i.e. ruimtelike, frekwensie- en tyddiversiteit), deur die gebruik van verskeie metodes van gesamentlike opsporing by die ontvanger. Daar is aangetoon dat die diversiteitwins in blokwegsterwingkanale verbeter kan word deur kodering oor veelvuldige deinende blokke [10–12]. Enkel-antenna TF-domeinverspreiding VD-DS-KVVT word oorweeg vir die kwasi-sinchroniese opverbinding-kanaal, en multi-antenna TF-domeinverspreiding VD-DS-KVVT vir die sinchroniese afverbinding-kanaal. Talryke gesimuleerde bisfouttempo (BFT) werkverrigtingkurwes wat verkry is deur die gebruik van ’n drie-voudige selektiewe VIVU-kanaalplatform, word in hierdie studie aangebied, deur die gebruik van optimale en sub-optimale gesamentlike opsporingsalgoritmes by die ontvanger. Daarbenewens ondersoek hierdie studie die impak van ruimtelike korrelasie op die BFT-werkverrigring van die VD-DS-KVVT-skemas wat oorweeg word. Uit hierdie gesimuleerde resultate is dit moontlik om tot die gevolgtrekking te kom dat TF-domeinverspreiding VD-DS-KVVT wat ontwerp is vir frekwensie-selektiese blokwegsterwingkanale beter werkverrigting toon as vroe¨er voorgestelde skemas wat ontwerp is vir frekwensie-selektiewe stadig deinende kanale, te danke aan die ekstra tyddiversiteit wat deur die blokwegsterwing-aanname benut word. Copyright / Dissertation (MEng)--University of Pretoria, 2010. / Electrical, Electronic and Computer Engineering / unrestricted
43

Mikromechanischer Prozess zur Herstellung mehrlagiger 3D-MEMS (EPyC-Prozess)

Louriki, Latifa 05 May 2021 (has links)
In der vorliegenden Dissertation wird die Entwicklung eines MEMS Herstellungsverfahrens beschrieben. Der Bosch patentierte EPyC-Prozess bietet die Möglichkeit komplexe MEMS-Strukturen mit hoher Effektivität auf engem Raum herzustellen. Zielsetzung dieser Arbeit ist die Untersuchung und Optimierung der EPyC-Einzelprozesse, sowie der Aufbau eines Mikrospiegelantriebs mit 40 μm hohen Elektrodenfingern für hohe z-Auslenkungen. Die Herstellung von MEMS-Strukturen mit dem EPyC-Prozess erfordert eine gute elektrische und mechanische Funktionalität der dicken epitaktischen Siliziumschichten. Durch Wiederholung der EPyC-Zyklen entsteht eine 3D-Opferstruktur. Die Herausforderung besteht darin, hohe Volumina an Polysilizium am Ende des Prozesses vollständig zu entfernen. Durch das Wiederholen von fünf EPyC Zyklen wurde der Mikrospiegelantrieb mit 40 μm hohen vertikalen Kammelektroden erfolgreich hergestellt. Anschließend wurde der Mikrospiegelantrieb mit dem optimierten Silizium-Ätzprozess in zwei Schritten freigestellt. Damit der Mikrospiegelantrieb mechanisch beweglich und elektrisch funktional wird, wurde die SiO2-Passivierung auf den Funktionsstrukturen mittels HF-Gasphasenätzen erfolgreich entfernt. Die elektrischen und mechanischen Funktionalitäten des Mikrospiegelantriebes wurden mittels Laservibrometer geprüft und bestätigt.:1 Einleitung 1 1.1 Stand der Technik 3 1.2 Zielsetzung 6 1.3 EPyC-Prozess 7 2 Methoden 16 2.1 Abscheideverfahren 16 2.1.1 Chemische Depositionsverfahren 16 2.1.2 LPCVD-Verfahren 17 2.1.3 Thermische Oxidation 22 2.1.4 Kathodenstrahlzerstäubung (Sputtern) 23 2.2 Silizium Dotieren 24 2.3 Strukturieren von Silizium mit dem DRIE-Prozess (Deep Reactive Ion Etching) 24 2.4 Strukturieren von dielektrischen Schichten: Reaktiven Ionenätzen (RIE) 27 2.5 Gasphasenätzen von Oxid mit HF-Dampf 28 2.6 Isotopes Silizium-Opferschicht Trockenätzen 28 2.6.1 Plasmaloses isotropes Siliziumätzen mit Xenondifluorid 28 2.6.2 Plasmaunterstütztes isotropes Siliziumätzen mit Schwefelhexafluorid 31 2.7 Charakterisierung der abgeschiedenen Schichten 31 2.7.1 Kristallstruktur 31 2.7.2 Mechanische Charakterisierung 33 2.7.3 Elektrische Charakterisierung 37 2.8 Elektrische und mechanische Charakterisierung der hergestellten 3D-MEMS Struktur 38 3 Ergebnisse 41 3.1 Ablauf des Herstellungsprozesses eines einzelnen EPyC-Zyklus mit unterschiedlich dicken Epi und ihre Charakterisierung 41 3.1.1 Ablauf der Abscheidung eines einzelnen EPyC-Zyklus 44 3.1.2 Charakterisierung der abgeschiedenen Schichten 50 3.1.2.3.1 Epi-Schicht (𝒅 = 𝟐𝟎 μ𝒎) 61 3.1.3 DRIE-Prozess für dicke Epi-Schichten 64 3.1.4 Trench-Verfüllung 69 3.1.5 Siliziumopferschichttechnik 86 3.2 Herstellung eines Mikrospiegelantriebs mittels fünf EPyC Zyklen 105 3.2.1 Ablauf der Mikrospiegelantriebsherstellung mittels EPyC-Prozesses 106 3.2.2 Charakterisierung des hergestellten Mikrospiegelantriebs 115 4 Zusammenfassung Abbildungsverzeichnis Tabellenverzeichnis Eigene Veröffentlichungen Thesen
44

Emotion structure, emotion meaning and emotion episodes of white Afrikaans–speaking working adults / van der Merwe, A.S.

Van der Merwe, Aletta Sophia January 2011 (has links)
Emotion research is an important research topic, thus making the measurement of emotion in the workplace crucial. In attempting to study, understand and measure the role of emotions in the human condition, various researchers have identified different theoretical models to manage the information they have gathered and the observations they have made. In order to study or scientifically investigate any human behaviour, it is essential that such behaviour can be measured, if not quantitatively, then at least qualitatively. However, what one finds with regard to emotion research and measurement are two–dimensional models. The existing affect has been described with a choice of two dimensions and structures, i.e. circumplex, positive and negative affect, tense and energetic arousal, and eight combinations of pleasantness and activation. These two dimensions and structures measure a person’s experiences and, thereafter, report them. The question is if these two–dimensional emotion models are sufficient to cover the broad and often complex dynamics of emotions. The start of multiple–emotion dimension models were reported by researchers, who identified a three–dimensional structure in the emotion domain that is suggestive of the Evaluation–Potency– Activation (EPA) dimensions in the connotative or affective meaning of words. However, in recent studies the sufficiency of two–dimension models to comprehensively investigate emotions was questioned. The three–dimensional emotion model was replicated in cross–cultural similarity sorting studies by other researchers. The similarity sorting studies also indicate the importance of studying emotions in specific cultural contexts. Studying emotion in different cultures is especially relevant in a country such as South Africa that has a variety of cultures and eleven official languages. Researchers followed an approach that studied the meaning of emotion in different cultural groups in the context of 144 emotion features using a componential emotion theory approach. Researchers argue in the groundbreaking research that was published in Psychological Science that emotion meaning has more than only two dimensions. The approach postulated by researchers was tested in a student population of three language groups, namely Dutch–, Englishand French–speaking students. According to researchers this is an empirical and theoretical method to study the meaning of emotions across cultures. However, apart from studying the meaning of emotions in specific cultural groups, research also attempts to determine the meaning of emotion in the natural contexts in which they occur. The relevant natural contexts for the field of Industrial Psychology are the work contexts. It is therefore also important to investigate the categories of emotion episodes in the work environment. The general goal of this study was therefore a) to investigate the emotion lexicon in the white Afrikaans–speaking working adult language group, b) to determine the cognitive emotion structure of this cultural group, c) to investigate the meaning of emotion as comprehensively as possible (multidimensional models of the meaning of emotion), and d) to determine the meaning and content of emotion episodes in the workplace. Research Article 1 The research was subsequently presented in two independent phases. Firstly, a free listing of emotion terms was compiled, and secondly the emotion terms were prototypically rated by Afrikaans–speaking people in South Africa. Both of these were then used as measuring instruments. A survey was designed to explore the research objectives utilising availability samples in two studies. The participants in the free–listing (N=70) and in the prototypicality (N=70) study consisted of native Afrikaans–speaking employees. The sample consisted of participants from the white ethnic group speaking Afrikaans within the Eastern Cape, Gauteng, Free State, Mpumalanga, North–West and KZN provinces and use was made of an availability sample. After conducting the research, the emotion terms with the highest frequency, as identified during the first study, the free listing task, were to be happy (gelukkig wees), be sad (hartseer wees), love (liefde), anger (kwaad) and hateful (haatlik). The emotion terms with the lowest scores as identified during the free listing were uncomfortable (ongemaklik), painful (seer), be hurt (seergemaak wees), sympathetic (simpatiek) and shout/yell (skreeu). Correspondingly, the five (5) prototypical terms with the highest scores in Afrikaans were nice (lekker), fed–up/had enough (gatvol/“genoeg gehad”), loveable (liefdevol), anger (kwaad) and to be scared (om bang te wees). The five (5) least prototypical terms from the list generated in the free listing task were: unstable (onvas), bashfulness (skugterheid), captivation (geboeidheid), envy (naywer) and delight (opgetoënheid). From the information obtained in this research it was revealed that the emotion terms nice (lekker), fed up/had enough (gatvol/“genoeg gehad”) and loveable (liefdevol) are at this stage unique to the white Afrikaans language group. These terms had not been reported in any previously conducted prototypical studies. The results of this study contribute to a cross–cultural understanding of the emotion concepts within the Afrikaans–speaking language groups in South Africa. Research Article 2 A survey design was used to achieve the research objectives utilising availability samples in a series of one study. The participants of the Similarity study (N=131) consisted of native Afrikaans–speaking employees. The sample consisted of participants from the white ethnicity group speaking Afrikaans within the Eastern Cape, Gauteng, Free State, Mpumalanga, North– West, KZN and Northern Cape provinces and use was made of an availability sample. Results of Multidimensional Scaling revealed a three–dimensional cognitive emotion structure. The first dimension was the evaluation–pleasantness dimension. This dimension evaluates the pleasantness versus the unpleasantness of an emotion. This dimension is characterised by intrinsic appraisals of pleasantness and goal conduciveness and action tendencies of approach versus avoidance. The second dimension that emerged was a power–control dimension. This dimension is characterised by appraisals of control, how powerful or weak a person feels when a particular emotion is experienced. This includes feelings of dominance or submission, the impulse to act or withdraw and changes in speech and parasymphatic symptoms. The third dimension which emerged was an activation–arousal dimension. According to other researchers this arousal dimension is characterised by sympathetic arousal, e.g. rapid heartbeat and readiness for action. This study produced a cognitive emotion structure in a white Afrikaans–speaking working adult population in South Africa. To add value to the field of Industrial Psychology, the threedimension structure (evaluation–pleasantness, power–control and activation–arousal dimension) that was found, is very important and valuable when studying the meaning of emotion and can consequently be used as a reference for other emotion research constructs. If it is accurate as stated in literature, there are three and not only two emotion dimension structures, and researchers are missing out on a bigger picture for not drawing on the experience of emotion sufficiently. Research Article 3 A survey design and an availability sample (N=120) in the Eastern Cape, Free State and Gauteng provinces in South Africa was utilised for this study. The Meaning Grid was translated and backtranslated and adapted for use in Afrikaans. The Cronbach's alpha coefficients were obtained for the emotion terms. According to the results of the Meaning Grid instrument, the following emotion terms were the highest: disgust (afkeur) 0,95; pleasure (plesier) 0,94; stress (stres) 0,92; happiness (blydskap) 0,91; joy (vreugde) 0,91; fear (bang) 0,91; anger (angstig) 0,91 and hate (haat) 0,90. The emotion terms that scored the lowest with the Meaning Grid instrument were compassion (medelye) 0,79; pride (trots) 0,79 and contempt (minagting) 0,74. Out of the 24 emotion terms of the Meaning Grid instrument, 8 terms were above 0,90 and 13 were between 0,80 and 0,89. Only 3 terms were between 0,74 and 0,79 [compassion (medelye), pride (trots) and contempt (minagting)]. A three–factor solution was found which represented four emotion dimensions (evaluation, arousal/unpredictability and power) that were universal to the emotion structures found in European samples. Factor scores of the 24 Meaning Grid emotions indicate a three–factor solution that explained 62,2 % of the total variance. The first factor was labelled evaluation and explained 43,0% of the variance, the second factor was labelled arousal/unpredictability as it was a combination of arousal and unpredictability and explained 11,0% of the variance, and the third factor was labelled power and explained 8,2% of the variance. This study followed an approach that investigated the meaning structure of emotion in the sample group in the context of 144 emotion features using a componential emotion theory approach. Different researchers argued that emotion meaning has more than only two dimensions. A three–dimensional emotion structure was found that was universal to the emotion structures of three language groups in a European sample. Therefore, the meaning of emotions for this sample group is far more complex than the two–dimensional emotion models that are found in literature. According to the componential emotion theory approach, the 144 emotion features are very important building blocks for Industrial Psychology when studying the meaning of emotion. Research Article 4 A survey design was used in this research study. The Episode Meaning Grid was administered and participants reported on the two intense emotion experiences at work (in total 358 episodes). Employees rated their emotion experiences on features based on the componential emotion theory and also described the emotion events in their own words. The participants in the emotion episodes (N=179) study consisted of native white Afrikaans–speaking working adults. The sample consisted of participants from the white ethnicity group speaking Afrikaans within the Eastern Cape, Free State and North–West provinces and use was made of an availability sample. The results indicated a three–dimensional structure (evaluation–pleasantness, activation–arousal and power–control dimension) was identified within a white Afrikaans–speaking working adult language group. The first dimension was an evaluation–pleasantness dimension. The second dimension was an activation–arousal dimension. The third dimension was a power–control dimension. Regarding the reporting of emotion episodes one hundred and ninety seven respondents reported 84 satisfying emotion episodes and 267 less satisfying emotion episodes that took place at work. Nine different categories of episodes for satisfying emotions experienced were mentioned. It consists of behaviour of work colleagues, acts of boss/superior/management, goal achievement, receiving recognition, workplace policy, task recognition, personal incidents, emotion involvement and subordinate behaviour. The three highest categories of satisfying emotions episodes were “Goal Achievement” (N=31), “Receiving Recognition” (N=20) and “Personal Incidents” (N=10). Goal achievement describes situations where job related targets or goals were met, and receiving recognition refers to positive feedback from managers, supervisors and work colleagues on meeting targets. Nineteen different categories of episodes for less satisfying emotion episodes were mentioned. It consists of behaviour of work colleagues, acts of boss/superior/management, lack of goal achievement, lack of receiving recognition, workplace policy, task requirement, personal incidents, emotional involvement, subordinate behaviour, workload, work mistakes, customer behaviour, external environment, lack of control, physical well–being, involvement in disciplinary action, workplace strikes, wellness of colleagues and unfairness in the workplace. In the categories of less satisfying emotions episodes, the three highest were “Behaviour of Work Colleagues” (N=58), “Acts of Boss/Superior/Management” (N=47) and “Task Requirement” (N=33). The first two categories are appraised less satisfying behaviour towards oneself or others by work colleagues, managers, supervisors and customers. In terms of the categories of satisfying and less satisfying emotions episodes, less satisfying emotion episodes outnumbered satisfying emotions episodes by three to one. By making use of a multi–componential emotion model, the results confirm that the four factors of pleasantness, power, arousal, and unpredictability, in that order of importance, are essential to satisfactorily determine the emotion experience and meaning of emotion terms. A threedimensional emotion structure (evaluation, arousal and power) was found after determining the meaning of emotion in the natural contexts in which they occur. The answer to the question if these two–dimensional emotion models, as stated in literature, are sufficient to cover the broad and often complex dynamics of emotion, is certainly no. Recommendations for the organisation and future research were made. / Thesis (Ph.D. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2012.
45

Emotion structure, emotion meaning and emotion episodes of white Afrikaans–speaking working adults / van der Merwe, A.S.

Van der Merwe, Aletta Sophia January 2011 (has links)
Emotion research is an important research topic, thus making the measurement of emotion in the workplace crucial. In attempting to study, understand and measure the role of emotions in the human condition, various researchers have identified different theoretical models to manage the information they have gathered and the observations they have made. In order to study or scientifically investigate any human behaviour, it is essential that such behaviour can be measured, if not quantitatively, then at least qualitatively. However, what one finds with regard to emotion research and measurement are two–dimensional models. The existing affect has been described with a choice of two dimensions and structures, i.e. circumplex, positive and negative affect, tense and energetic arousal, and eight combinations of pleasantness and activation. These two dimensions and structures measure a person’s experiences and, thereafter, report them. The question is if these two–dimensional emotion models are sufficient to cover the broad and often complex dynamics of emotions. The start of multiple–emotion dimension models were reported by researchers, who identified a three–dimensional structure in the emotion domain that is suggestive of the Evaluation–Potency– Activation (EPA) dimensions in the connotative or affective meaning of words. However, in recent studies the sufficiency of two–dimension models to comprehensively investigate emotions was questioned. The three–dimensional emotion model was replicated in cross–cultural similarity sorting studies by other researchers. The similarity sorting studies also indicate the importance of studying emotions in specific cultural contexts. Studying emotion in different cultures is especially relevant in a country such as South Africa that has a variety of cultures and eleven official languages. Researchers followed an approach that studied the meaning of emotion in different cultural groups in the context of 144 emotion features using a componential emotion theory approach. Researchers argue in the groundbreaking research that was published in Psychological Science that emotion meaning has more than only two dimensions. The approach postulated by researchers was tested in a student population of three language groups, namely Dutch–, Englishand French–speaking students. According to researchers this is an empirical and theoretical method to study the meaning of emotions across cultures. However, apart from studying the meaning of emotions in specific cultural groups, research also attempts to determine the meaning of emotion in the natural contexts in which they occur. The relevant natural contexts for the field of Industrial Psychology are the work contexts. It is therefore also important to investigate the categories of emotion episodes in the work environment. The general goal of this study was therefore a) to investigate the emotion lexicon in the white Afrikaans–speaking working adult language group, b) to determine the cognitive emotion structure of this cultural group, c) to investigate the meaning of emotion as comprehensively as possible (multidimensional models of the meaning of emotion), and d) to determine the meaning and content of emotion episodes in the workplace. Research Article 1 The research was subsequently presented in two independent phases. Firstly, a free listing of emotion terms was compiled, and secondly the emotion terms were prototypically rated by Afrikaans–speaking people in South Africa. Both of these were then used as measuring instruments. A survey was designed to explore the research objectives utilising availability samples in two studies. The participants in the free–listing (N=70) and in the prototypicality (N=70) study consisted of native Afrikaans–speaking employees. The sample consisted of participants from the white ethnic group speaking Afrikaans within the Eastern Cape, Gauteng, Free State, Mpumalanga, North–West and KZN provinces and use was made of an availability sample. After conducting the research, the emotion terms with the highest frequency, as identified during the first study, the free listing task, were to be happy (gelukkig wees), be sad (hartseer wees), love (liefde), anger (kwaad) and hateful (haatlik). The emotion terms with the lowest scores as identified during the free listing were uncomfortable (ongemaklik), painful (seer), be hurt (seergemaak wees), sympathetic (simpatiek) and shout/yell (skreeu). Correspondingly, the five (5) prototypical terms with the highest scores in Afrikaans were nice (lekker), fed–up/had enough (gatvol/“genoeg gehad”), loveable (liefdevol), anger (kwaad) and to be scared (om bang te wees). The five (5) least prototypical terms from the list generated in the free listing task were: unstable (onvas), bashfulness (skugterheid), captivation (geboeidheid), envy (naywer) and delight (opgetoënheid). From the information obtained in this research it was revealed that the emotion terms nice (lekker), fed up/had enough (gatvol/“genoeg gehad”) and loveable (liefdevol) are at this stage unique to the white Afrikaans language group. These terms had not been reported in any previously conducted prototypical studies. The results of this study contribute to a cross–cultural understanding of the emotion concepts within the Afrikaans–speaking language groups in South Africa. Research Article 2 A survey design was used to achieve the research objectives utilising availability samples in a series of one study. The participants of the Similarity study (N=131) consisted of native Afrikaans–speaking employees. The sample consisted of participants from the white ethnicity group speaking Afrikaans within the Eastern Cape, Gauteng, Free State, Mpumalanga, North– West, KZN and Northern Cape provinces and use was made of an availability sample. Results of Multidimensional Scaling revealed a three–dimensional cognitive emotion structure. The first dimension was the evaluation–pleasantness dimension. This dimension evaluates the pleasantness versus the unpleasantness of an emotion. This dimension is characterised by intrinsic appraisals of pleasantness and goal conduciveness and action tendencies of approach versus avoidance. The second dimension that emerged was a power–control dimension. This dimension is characterised by appraisals of control, how powerful or weak a person feels when a particular emotion is experienced. This includes feelings of dominance or submission, the impulse to act or withdraw and changes in speech and parasymphatic symptoms. The third dimension which emerged was an activation–arousal dimension. According to other researchers this arousal dimension is characterised by sympathetic arousal, e.g. rapid heartbeat and readiness for action. This study produced a cognitive emotion structure in a white Afrikaans–speaking working adult population in South Africa. To add value to the field of Industrial Psychology, the threedimension structure (evaluation–pleasantness, power–control and activation–arousal dimension) that was found, is very important and valuable when studying the meaning of emotion and can consequently be used as a reference for other emotion research constructs. If it is accurate as stated in literature, there are three and not only two emotion dimension structures, and researchers are missing out on a bigger picture for not drawing on the experience of emotion sufficiently. Research Article 3 A survey design and an availability sample (N=120) in the Eastern Cape, Free State and Gauteng provinces in South Africa was utilised for this study. The Meaning Grid was translated and backtranslated and adapted for use in Afrikaans. The Cronbach's alpha coefficients were obtained for the emotion terms. According to the results of the Meaning Grid instrument, the following emotion terms were the highest: disgust (afkeur) 0,95; pleasure (plesier) 0,94; stress (stres) 0,92; happiness (blydskap) 0,91; joy (vreugde) 0,91; fear (bang) 0,91; anger (angstig) 0,91 and hate (haat) 0,90. The emotion terms that scored the lowest with the Meaning Grid instrument were compassion (medelye) 0,79; pride (trots) 0,79 and contempt (minagting) 0,74. Out of the 24 emotion terms of the Meaning Grid instrument, 8 terms were above 0,90 and 13 were between 0,80 and 0,89. Only 3 terms were between 0,74 and 0,79 [compassion (medelye), pride (trots) and contempt (minagting)]. A three–factor solution was found which represented four emotion dimensions (evaluation, arousal/unpredictability and power) that were universal to the emotion structures found in European samples. Factor scores of the 24 Meaning Grid emotions indicate a three–factor solution that explained 62,2 % of the total variance. The first factor was labelled evaluation and explained 43,0% of the variance, the second factor was labelled arousal/unpredictability as it was a combination of arousal and unpredictability and explained 11,0% of the variance, and the third factor was labelled power and explained 8,2% of the variance. This study followed an approach that investigated the meaning structure of emotion in the sample group in the context of 144 emotion features using a componential emotion theory approach. Different researchers argued that emotion meaning has more than only two dimensions. A three–dimensional emotion structure was found that was universal to the emotion structures of three language groups in a European sample. Therefore, the meaning of emotions for this sample group is far more complex than the two–dimensional emotion models that are found in literature. According to the componential emotion theory approach, the 144 emotion features are very important building blocks for Industrial Psychology when studying the meaning of emotion. Research Article 4 A survey design was used in this research study. The Episode Meaning Grid was administered and participants reported on the two intense emotion experiences at work (in total 358 episodes). Employees rated their emotion experiences on features based on the componential emotion theory and also described the emotion events in their own words. The participants in the emotion episodes (N=179) study consisted of native white Afrikaans–speaking working adults. The sample consisted of participants from the white ethnicity group speaking Afrikaans within the Eastern Cape, Free State and North–West provinces and use was made of an availability sample. The results indicated a three–dimensional structure (evaluation–pleasantness, activation–arousal and power–control dimension) was identified within a white Afrikaans–speaking working adult language group. The first dimension was an evaluation–pleasantness dimension. The second dimension was an activation–arousal dimension. The third dimension was a power–control dimension. Regarding the reporting of emotion episodes one hundred and ninety seven respondents reported 84 satisfying emotion episodes and 267 less satisfying emotion episodes that took place at work. Nine different categories of episodes for satisfying emotions experienced were mentioned. It consists of behaviour of work colleagues, acts of boss/superior/management, goal achievement, receiving recognition, workplace policy, task recognition, personal incidents, emotion involvement and subordinate behaviour. The three highest categories of satisfying emotions episodes were “Goal Achievement” (N=31), “Receiving Recognition” (N=20) and “Personal Incidents” (N=10). Goal achievement describes situations where job related targets or goals were met, and receiving recognition refers to positive feedback from managers, supervisors and work colleagues on meeting targets. Nineteen different categories of episodes for less satisfying emotion episodes were mentioned. It consists of behaviour of work colleagues, acts of boss/superior/management, lack of goal achievement, lack of receiving recognition, workplace policy, task requirement, personal incidents, emotional involvement, subordinate behaviour, workload, work mistakes, customer behaviour, external environment, lack of control, physical well–being, involvement in disciplinary action, workplace strikes, wellness of colleagues and unfairness in the workplace. In the categories of less satisfying emotions episodes, the three highest were “Behaviour of Work Colleagues” (N=58), “Acts of Boss/Superior/Management” (N=47) and “Task Requirement” (N=33). The first two categories are appraised less satisfying behaviour towards oneself or others by work colleagues, managers, supervisors and customers. In terms of the categories of satisfying and less satisfying emotions episodes, less satisfying emotion episodes outnumbered satisfying emotions episodes by three to one. By making use of a multi–componential emotion model, the results confirm that the four factors of pleasantness, power, arousal, and unpredictability, in that order of importance, are essential to satisfactorily determine the emotion experience and meaning of emotion terms. A threedimensional emotion structure (evaluation, arousal and power) was found after determining the meaning of emotion in the natural contexts in which they occur. The answer to the question if these two–dimensional emotion models, as stated in literature, are sufficient to cover the broad and often complex dynamics of emotion, is certainly no. Recommendations for the organisation and future research were made. / Thesis (Ph.D. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2012.

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