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Text in English with abstracts in English, Afrikaans and Venda / In this qualitative study, the research objective was to present a theoretical framework for the phenomenon of interpersonal leadership relations (denoting both the dyadic relationship between two leader/followers and the leadership communication taking place in the dyad) in knowledge-based organisational contexts. It is posited that the interpersonal leader-follower dyad (LFD) may be viewed from a systems theory perspective as a system consisting of two system parts (individuals). These individuals are labelled ‘leader/followers’ to emphasise their mutual interdependence, and to indicate that these roles may be interchangeable, based on the knowledge needs in a particular situation (in line with the tenets of shared leadership). The dyadic system is influenced by its environment, the organisational context. However, the primary focus of this study is on interpersonal leadership communication as symbolic interaction between the leader/followers in the LFD. These three systemic levels are represented as major themes in the model resulting from this study: Theme 1 – an organisational environment that supports constructive interpersonal leadership relations (ILR); Theme 2 – symbolic interaction in the LFD; and Theme 3 – personal attributes that enhance ILR. The data were collected from two convenience samples. In-depth, semi-structured interviews were conducted with participants in Sample 1, while questionnaires were used to collect data from Sample 2. In both cases, thematic analysis was used to analyse and interpret the data. The major contribution of the study is the resulting theoretical framework of ILR, which comprises a theoretically based definition of ILR; a generic model of ILR; and current guidelines for fostering constructive ILR in knowledge-based contexts, with reference to the three systemic levels. The following definition was phrased based on the study: Constructive interpersonal leadership relations (ILR) in a knowledge-based organisational context is a dyadic process of symbolic communication between two expert leader/followers who mutually influence each other and share meaning to strengthen their relationship and to collaboratively transfer and apply knowledge to achieve organisational goals. In terms of the environment, it was found that organisational leaders should actively model and promote the following: a collaborative leadership concept, workplace spirituality, cultural inclusivity, and adaptation to advancing communication technologies. Regarding symbolic interaction in the LFD, the following communication practices were found to be central to constructive ILR: active listening, supporting followers as unique individuals, respectful communication, considering followers’ input, facilitating constructive redefinition of the other leader/follower’s self, role-taking (taking the perspective of the other leader/follower’s role), awareness of attribution, conflict management through non-threatening, respectful and preferably face-to-face discussion, facilitating a sense of meaning or purpose at work for the other leader/follower, and fostering constructive relationship properties such as trust. It was found that ILR may produce system outputs into the organisation that contribute to the organisational culture and climate, job performance, employee morale and engagement, and staff retention. Personal attributes were organised into personal values and competencies that support ILR. The most important personal values were identified as honesty, love or supportiveness, respect, relationships or engagement, trust, and professional excellence. Essential competencies were identified as listening skills, emotional communication competencies (particularly self-awareness, self-reflection and attending to others’ emotions), engagement skills, conflict management skills, and multicultural competency (including generational skills). / In hierdie kwalitatiewe studie word ’n teoretiese raamwerk voorgelê vir die verskynsel ‘interpersoonlike leierskapsverhoudings‘ (verwysende na beide die diadiese verhouding tussen twee leier/volgelinge en die leierskapskommunikasie wat in die diade plaasvind) in kennisgebaseerde organisatoriese kontekste. Die uitgangspunt is dat die interpersoonlike leier-volgeling-diade (LVD) vanuit ‘n sisteemteoretiese perspektief beskou kan word as ‘n sisteem wat uit twee sisteemdele (individue) bestaan. Hierdie individue word ‘leier/volgelinge‘ genoem om hulle wedersydse interafhanklikheid te beklemtoon; en om aan te toon dat hierdie rolle uitruilbaar mag wees, afhangende van die kennisbehoeftes in ’n gegewe situasie (met verwysing na die teorie van gedeelde leierskap). As ’n sisteem word die LVD ook deur die omringende omgewing of organisatoriese konteks beïnvloed. Die primêre fokus van hierdie studie is egter op interpersoonlike leierskapskommunikasie as simboliese interaksie tussen die leier/volgelinge in die LVD. Hierdie drie sistemiese vlakke word in hierdie studie deur die hooftemas in die studie verteenwoordig en ook as sulks in die voortvloeiende model uitgebeeld: Tema 1 – ’n organisatoriese omgewing wat konstruktiewe interpersoonlike leierskapsverhoudings (ILV) ondersteun; Tema 2 – simboliese interaksie in die LVD; en Tema 3 – persoonlike eienskappe wat ILV bevorder. Die teoretiese raamwerk van ILV bestaan uit die volgende: ’n teoreties gefundeerde definisie van ILV; ’n generiese model van ILV; en ’n raamwerk van huidige riglyne vir die kweek van konstruktiewe ILV in kennisgebaseerde kontekste, met verwysing na die drie sistemiese vlakke van omgewing, diade en individuele leier/volgelinge. Die volgende definisie is op grond van die navorsingsresultate geformuleer: Konstruktiewe interpersoonlike leierskapsverhoudings (ILV) in ’n kennisgebaseerde organisatoriese konteks is ’n diadiese proses van simboliese kommunikasie tussen twee kundige leier/volgelinge wat mekaar wedersyds beïnvloed en betekenis deel om hulle verhouding te versterk en kennis samewerkend oor te dra en aan te wend om organisatoriese doelwitte te bereik. In terme van die organisatoriese omgewing is bevind dat organisatoriese leiers, veral senior leiers, die volgende aktief moet modelleer en bevorder in die organisasie: ’n samewerkende leierskapskonsep, spiritualiteit in die werkplek, kulturele insluiting, en aanpassing by vooruitgang in kommunikasietegnologie. Met verwysing na simboliese interaksie in die LVD is die volgende praktyke bevind as sentraal tot konstruktiewe ILV: aktiewe luistergedrag, die ondersteuning van volgelinge as unieke individue, respekvolle kommunikasie, die inagneming van volgelinge se insette, die fasilitering van die konstruktiewe herdefiniëring van die ander leier/volgeling se self, rol-inneming (die inneem van die rolperspektief van die ander leier/volgeling), bewustheid van attribusie, die bestuur van konflik deur nie-bedreigende, respekvolle en – waar moontlik – aangesig-tot-aangesig bespreking, die fasilitering van ’n sin van doel of betekenis by die werk vir die ander leier/volgeling, en die kweek van konstruktiewe verhoudingseienskappe (vertroue, uitruilbare leier/volgeling-rolle en wedersydse invloed is geïdentifiseer as belangrik). Dit is ook bevind dat ILV sisteemuitsette in die organisasie mag genereer wat bydra tot die organisatoriese kultuur en klimaat, werkprestasie, werknemers se moreel en betrokkenheid, en personeelbehoud. Persoonlike eienskappe is verdeel in waardes en vaardighede wat ILV ondersteun. Die belangrikste waardes is geïdentifiseer as eerlikheid, liefde, respek, verhoudings, vertroue, en professionele uitnemendheid. Die volgende vaardighede is geïdentifiseer as noodsaaklik: luistervaardighede, emosionele kommunikasievaardighede (met spesifieke verwysing na selfbewussyn, selfrefleksie en aandag aan ander se emosies), betrekkingsvaardighede, konflikbestuursvaardighede, en multi-kulturele vaardighede (wat generasievaardighede insluit). Die date is ingesamel uit twee gerieflikheidsteekproewe. Indiepte-, semi-gestruktureerde onderhoude is gevoer met Steekproef 1 (kundiges op gebiede verwant aan ILV in kennisgebaseerde kontekste), terwyl vraelyste gebruik is om data te verkry by Steekproef 2 (leier/volgelinge in kennisgebaseerde kontekste). Tematiese ontleding is in beide gevalle gebruik om die data te ontleed en te interpreteer. / Kha iyi ngudo ya u tandula ‘qualitative’, ndivho ya ṱhoḓisio yo vha u ṋetshedza mutheo wa thiyori kha sia ḽa vhushaka ha vhurangaphanḓa vhukati ha vhathu (zwine zwa amba vhushaka ha tshumisano vhukati ha vharangaphanḓa/vhatevheli vhavhili na vhudavhidzani kha vhurangaphanḓa vhune ha khou bvelela nga kha tshumisano yeneyo) kha nyimele ya tshiimiswa yo ḓitikaho nga nḓivho. Zwo sumbedziswa uri tshumisano ya murangaphanḓa-mutevheli vhukati ha vhathu (leader-follower dyad (LFD)) i nga lavheleswa u bva kha sia ḽa sisiṱeme ya thyori sa sisiṱeme ine ya vha na zwipiḓa zwivhili (vhathu). Vhathu avha vha vhidzwa ‘vharangaphanḓa/vhatevheli’ hu u itela u khwaṱhisedza u ḓitika havho nga muṅwe, na u sumbedza uri mishumo iyi i nga imelelana, zwo ḓitika nga ṱhoḓea dza nyimele yeneyo. (zwi tshi tevhedza vhatevheli vha vhurangaphanḓa uvho). Sisiṱeme ya tshumisano i ṱuṱuwedzwa nga nyimele yayo, nyimele ya tshiimiswa. Fhedziha zwa ndeme kha ngudo iyi ndi nga vhudavhidzani ha vhurangaphanḓa vhukati ha vhathu sa tshiga tsha tshumisano vhukati ha vharangaphanḓa/vhatevheli kha LFD. Maga aya mararu a sisisṱeme a imelelwa nga ṱhoho khulwane kha nḓila yo livhisaho kha ngudo iyi: Ṱhoho 1 – mupo/nyimele ya tshiimiswa i ṱuṱuwedzaho vhushaka ha vhurangaphanḓa vhu vhuedzaho vhukati ha vhathu (interpersonal leadership relations (ILR)); Ṱhoho 2 – Tshiga tsha tshumisano kha LFD; na Ṱhoho 3 – Vhuvha ha muthu vhune ha konisa ILR. Data yo kuvhanganywa u bva kha sambula dzine dza vha dza tsinisa. Mbudziso dzo ṱanḓavhuwaho, dzi sa langiho kufhindulele kha vhavhudziswa dzo itwa hu na vhadzheneli kha Sambula ya u thoma (1), ngeno khwesheya dzo shumiswa u kuvhanganya data kha Sambula 2. Kha nyimele dzoṱhe ho shumiswa ṱhaṱhuvho i re na vhushaka na ṱhoho u itela u ṱhaṱhuvha na u ṱalutshedza data. Zwine ngudo iyi ya vhuedza khazwo ndi mvelelo ya mutheo wa thyori wa ILR, ine ya vha na ṱhalutshedzo yo ḓitikaho nga thyori ya ILR, nḓila ya u angaredza ya ILR; na tsumbanḓila dza zwino u itela mbuelo ya ILR kha nyimele yo ḓitikaho nga nḓivho, zwo lavhelesa kha maga a sisiṱeme. Ṱhalutshedzo i tevhelaho yo vhekanywa zwi ḓitika nga ngudo: Vhushaka ha vhurangaphanḓa Vhuvhedzaho vhukati ha vhathu (ILR) kha nyimele ya tshiimiswa yo ḓitikaho nga nḓivho ndi maitele a tshumisano ya tshiga tsha vhudavhidzani vhukati ha vharangaphanḓa/vhatevheli vha re na nḓivho vhane vha ṱuṱuwedzana na u kovhekana zwine zwa amba u itela u khwaṱhisa vhushaka havho khathihi na u fhirisa na u shumisa nḓivho u itela u zwikelela zwipikwa zwa tshiimiswa. Zwi tshi ya nga nyimele, zwo wanala uri vharangaphanḓa vha tshiimiswa vha tea u vhumba na u ṱuṱuwedza zwi tevhelaho: muhumbulo wa tshumisano kha vhurangaphanḓa, zwa tshimuya mushumoni, u katela zwa mvelele, na u ṱanganedza u shumiswa ha thekhinoḽodzhi ya vhudavhidzani. Maelana na tshumisano nga tshiga kha LFD, maitele a vhudavhidzani a tevhelaho a wanala a one a ndeme kha ILR ire na mbuelo: u thetshelesa nga vhuronwane, u tikedza vhatevheli hu na kupfesesele kwa uri vhathu vho fhambana, vhudavhidzani ha ṱhonifho, u dzhiela nṱha mihumbulo ya vhatevheli, u ṱuṱuwedza u ṱhalutshedza nga nḓila yo fhambanaho i vhuedzaho ya vhaṅwe vharangaphanḓa/vhatevheli vha shumaho u ya nga vhone vhaṋe, u dzhia dzhenelela (u vhona nga nḓila ine vhaṅwe vharangaphanḓa/vhatevheli vha vona ngayo), u tangnedza nḓivho, ndaulo ya phambano nga kha nyambedzano i sa shushedziho, ya ṱhonifho, nga maanḓa nga nyambedzano vhathu vho livhana zwifhaṱuwo, u ṱuṱuwedza nḓivho ya ṱhalutshedzo kana ndivho ya mushumo kha vhaṅwe vharangaphanḓa/vhatevheli, u ṱuṱuwedza zwithu zwi fhaṱaho vhushaka vhu vhuedzaho u fana na u fulufhedzana. Zwo tumbulwa uri ILR i bveledza sisiṱeme ya mvelelo u vha tshiimiswa tshine tsha dzhenelela kha mvelele na vhuḓipfi, kushumele kwa mushumo, u ṱuṱuwedzea na u dzhenelela ha vhashumi, nauri vhashumi vha sa ṱuwe. U ṱanganedzea ha muthu zwo vheekanywa zwi tshi ya nga mikhwa ya muthu ene muṋe na vhukoni zwine zwa tikedza ILR. Mikhwa ya muthu ya ndemesa yo topolwa sa u fulufhedzea, lufuno, ṱhonifho kana u dzhenelela, fulufhelo, na vhukoni kha zwa phurofeshinaḽa. Vhukoni ha ndeme ho sumbedzwa sa vhukoni ha u thetshelesa, vhukoni ha vhudavhidzani ha muhumbulo (nga maanḓa u ḓiḓivha, u ḓilingulula/sedzulusa na u dzhiela nzhele vhuḓipfi ha vhaṅwe vhathu), vhukoni ha u dzhenelela, vhukoni ha ndaulo ya phambano, na vhukoni ha u dzhenelela kha mvelele nnzhi (zwi tshi katela vhukoni ha zwa murafho). / Communication Science / D. Litt. et Phil. (Communication)

Cette thèse de doctorat porte sur le calcul par la méthode des éléments finis du comportement dynamique de réservoirs élastiques précontraints contenant un liquide interne à surface libre. Nous considérons que la pression hydrostatique exercée par le fluide interne incompressible sur les parois flexibles du réservoir est à l’origine de grands déplacements, conduisant ainsi à un état d’équilibre non-linéaire géométrique. Le changement de raideur lié à cet état précontraint induit un décalage des fréquences de résonances du problème de vibrations linéaires couplées.L’objectif principal du travail est donc d’estimer, par des approches numériques précises et efficaces, l’influence des non-linéarités géométriques sur le comportement hydroélastique du système réservoir/liquide interne autour de différentes configurations d’équilibre. La méthodologie développée s’effectue en deux étapes. La première consiste à calculer l’état statique non-linéaire par une approche éléments finis lagrangienne totale. L’action du fluide sur la structure est ici modélisée par des forces suiveuses hydrostatiques. La deuxième étape porte sur le calcul des vibrations couplées linéarisées. Un modèle d’ordre réduit original est notamment proposé pour limiter les coûts de calcul associés à l’estimation de l’effet de masse ajoutée. Enfin, divers exemples sont proposés et comparés à des résultats de la littérature (issus de simulations numériques ou d’essais expérimentaux) pour montrer l’efficacité et la validité des différentes approches numériques développées dans ce travail. / This doctoral thesis focuses on the calculation by the finite element method of the dynamic behavior of prestressed elastic tanks containing an internal liquid with a free surface. We consider that the hydrostatic pressure exerted by the incompressible internal fluid on the flexible walls of the tank causes large displacements, thus leading to a geometric non-linear equilibrium state. The change of stiffness related to this prestressed state induces a shift in the resonance frequencies of the coupled linear vibration problem. The main objective of the work is therefore to estimate, through precise and efficient numerical approaches, the influence of geometric nonlinearities on the hydroelastic behavior of the reservoir/internal liquid system around different equilibrium configurations. The methodology developed is carried out in two stages. The first one consists in calculating the non-linear static state by a total Lagrangian finite element approach.The action of the fluid on the structure is modelled here by hydrostatic following forces. The second step is the calculation of linearized coupled vibrations. In particular, an original reduced order model is proposed to limit the calculation costs associated with the estimation of the added mass effect. Finally, various examples are proposed and compared with results from the literature (from numerical simulations or experimental tests) to show the effectiveness and validity of the different numerical approaches developed in this work.

2007年6月，華碩電腦發表Eee PC精簡式筆記型電腦，此創新產品俟後由臺灣資訊工業策進會市場情報中心（MIC）統稱為精簡型小筆電，簡稱小筆電，英文名稱則採用美商英代爾對於這款產品的統稱：Netbook。 Eee PC所設定的目標市場著眼於消費性市場，將產品定位於已開發國家使用者的第二臺電腦以及開發中國家使用者的第一臺電腦。產品上市後掀起銷售高潮，由於小筆電的加入，筆記型電腦在2008年第三季出貨量首度超越桌上型電腦，比先前2007年預估提早兩年，Eee PC因而被譽為臺灣電腦廠商價值創新的一大步。 本研究主要的探討問題有四：核心技術能耐發展策略對於產品創新的影響為何？ 品牌與ODM廠商在創新產品開發上的合作與分工為何？ 品牌廠商因應競爭者之破壞性創新的作法為何？ 核心技術能耐為基礎的產品創新在市場上所需具備的成功條件為何？ 在研究設計上以策略與組織、技術、市場三構面做為主要分析架構。策略與組織構面由領導者企圖心、核心競爭優勢、企業文化、組織架構、企業網絡定位等變項構成；技術構面上由產品研發經驗、內部知識傳遞、外部資源網絡、產品開發管理等變項構成；市場構面由品牌效益、顧客需求、產品行銷、產業合作網絡等變項組成用以探討對於破壞性創新產品構思及開發階段的影響。研究方法上採用「個案研究法」，以領導廠商華碩與宏碁為研究對象。在資料上透過企業訪談與次級資料蒐集的方式來了解個案公司在創新產品的發展過程，並結合核心競爭力、產業價值鏈、破壞性創新、新產品開發程序、吸收能耐與知識傳遞、技術面競爭策略等學理加以分析，本研究所獲得的研究發現如下： 一．建立核心競爭能耐的方向及重點決定了企業在產業價值鏈的位置與所從事的價值活動。 二．企業基於核心技術能耐發展策略而對產品創新方向做出技術領導者與技術追隨者的不同策略選擇。技術領導者著重產品的破壞性創新設計，技術追隨者著重於產品成熟技術的市場性。 三．品牌廠商與ODM的研發製造合作關係上，考量中心點在於顧客對企業的認知價值。品牌廠商並以平均分配（Allocation）與相互制衡（Leverage）為策略，取得各家資源之長為己用。 四．設計代工廠從OEM經營模式進入ODM經營模式，在逐步接手研發價值活動後，ODM設計製造廠開始投入自主研發，成為個人電腦產品技術提供者。但在缺乏通路品牌下，所創造的產品創新價值只能透過品牌廠技術採用將創新價值傳達至消費者。 五．企業發展破壞性創新產品時，原價值網絡上具產業主導地位的供應商透過關鍵技術的掌握，並經由品牌行銷掌握終端使用者，形成不易突破的慣性，對於廠商產品創新產生鉗制作用。 六．企業發展破壞性創新產品若無法取得市場客戶對產品的價值認同，則雖有技術成就，但難以成為產品的競爭優勢。 七．企業在發展破壞性創新產品過程中，若缺乏行銷業務部門參與，將可能造成產品上市後的市場資訊掌握失準。 八．破壞性創新產品所設定於原價值網絡的目標市場，往往因為高科技產業的不確定性因素，在實際執行時意外產生新應用，產品因而進入新價值網絡的新市場。 九．破壞性創新產品進入新市場時不確定因素多，廠商因需求不易掌握而經常發生嘗試錯誤的探索行為，但市場晚入者觀察先驅者經驗，往往能立即掌握正確資訊而迅速反應市場需求。 十．企業發展破壞性創新產品，若未造成有效技術差距，技術領導者與市場先驅者將不易維持首動者優勢。技術追隨者與市場晚入者藉由學習領導者經驗將有機會快速超越。 本研究最後並提出一些實務上建議，以做為產業界發展核心技術能耐策略與發展破壞性創新產品的參考。 / In June, 2007, Asus Computer announced her Eee PC in Computex Taipei, Taiwan International Computer Exhibition. The simplified notebook then named “Netbook” due to its lightweight design and focused internet application. Eee PC was aimed on consumer market of developed countries, targeted as “Secondary Computer” for existing computer users, as well as first computer to the user of the developing world, the name “Eee” derives from "the three Es", an abbreviation of its advertising slogan for the device: "Easy to learn, Easy to work, Easy to play". By third quarter of 2008, notebook shipped quantity including netbook, had exceeded desktop computer, two years advance from prior market research report’s estimation made before netbook product rollout in 2007. Eee PC was praised as stride-out of value innovation of Taiwan computer industry. Problem discoveries and definitions in this research are: first of all, what is the influence of core technology development strategy toward product innovation? Second, how brand owner works with ODM suppliers on innovative product development? Third, how brand owner reacts to disruptive innovation? Last, what are market successful factors of an innovative product which based on core technology competence? Analysis framework of this research consists of three aspects: strategy and organization, technology, marketing. As an exploratory study, research design is qualitative research and case study over certain firms: Asus and Acer, with 90% market shares of netbook in year 2008. For data gathering, primary data came from interviews to firms’ management team members, specifically R&D and PM Directors, secondary data studies came from varies sources: research reports, annual reports, and so on. To explore the influence of core technology competence toward product innovation in idea generation and product development stage, study of related theories in advance is necessary: core competence, value chain, disruptive innovation, new product development procedure, absorptive capability, knowledge transmission, and competitive strategy of technology. Discoveries of this research are: 1.Direction and focus of establishing core competence decides the firm’s position in value chain and the value activities firm engaged. 2.Core technology competence development strategy directs firm’s choice of technology leader or follower, leader focuses on innovative product design, follower focuses on mature technology’s market taking. 3.Customers perceive value is the key consideration that brand owners work with ODM suppliers. “Allocation and Leverage” are strategy that brand owners manage multiple ODM suppliers. 4.From OEM to ODM business model, ODM firms start to develop own independent research projects, this trend leads ODM to be technology supplier in foreseeable future. But, research results can only go through brand owners to consumer market. 5.Key technology suppliers of existing value network will obstruct disruptive innovation products through market’s inertia. 6.Technology based innovative products can’t have competitive advantage in the market without customer’s perceive value. 7.Sales marketing team’s participation is important for disruptive innovation during product development stage. 8.Unexpected new value network will emerge due to uncertainty of high-tech industry, new application out of target market leads to new value network which is different from existing one. 9.Pioneer frequently tries and error for disruptive innovation product due to uncertainty of market, late entrant learned from pioneer’s experience, and react to market demand efficiently. 10.Innovative product without technology gap, firm can’t maintain first mover advantage too long, technology follower have chance to transcend in short period. Conclusions of this research are summarized from above discoveries, and suggestions to industry firms made by this research can be reference to firms’ development strategy of core technology competence as well as product development of disruptive innovation.

L'objectif principal visé par cette thèse est de modéliser les poutres gonflables en textiles techniques orthotropes. Les approches statiques font l'objet de ce rapport. Avant d'aborder ce problème, nous avons été amenés à identifier tous les paramètres qui ont un effet direct sur les propriétés mécaniques effectives de ces composites. Ainsi, nous avons développé un modèle micro mécanique de prédiction de ces propriétés mécaniques. Le modèle proposé est basé sur l’analyse d'un volume élémentaire représentatif (VER) prenant en compte non seulement les propriétés mécaniques et la. fraction de volume de chaque phase dans le VER mais également leur géométrie et leur architecture. Chaque fil dans le VER a été modélisé comme un matériau isotrope transverse (contenant les fibres et la résine). La méthode dite d’assemblage de cylindres a été utilisée pour l’homogénéisation au niveau des fils. Une deuxième homogénéisation est ensuite réalisée. Elle prend en compte la fraction de volume de chaque constituant (fils de chaîne, fils de trame et résine non prise en compte dans les fils). Le modèle a été validé par des résultats expérimentaux existant dans la littérature. Une élude paramétrique a été menée afin d'étudier les effets des divers paramètres géométriques et mécaniques sur ces propriétés mécaniques. Dans l'analyse structurale, un modèle poutre gonflable 3D de Timoshenko en tissu orthotrope a été proposé. Il prend en compte les non-linéarités géométriques et l'effet de la force suiveuse générée par la pression de gonflage. Les équations d'équilibre non-linéaires dérivent du principe des travaux virtuels en configuration lagrangienne totale. Dans une première approche, une linéarisation a été faite autour de la configuration de référence précontrainte pour obtenir les équations adaptées aux problèmes linéaires. A titre d'exemple, le problème de flexion plane a été abordé. Quatre cas de conditions aux limites ont été traités et les résultats obtenus améliorent les modèles existants dans le cas de tissu isotrope. Les charges de plissage ont été également proposées dans chaque cas traité. Dans une deuxième approche, les équations non-linéaires ont été discrétisées par la méthode des éléments finis. Deux types de solutions ont été alors proposées : les solutions aux problèmes éléments finis linéaires obtenues par une linéarisation des équations discrétisées autour de la configuration de référence précontrainte et les solutions aux problèmes éléments finis non-linéaires réalisées en adoptant une méthode Quasi-Newton sous sa forme incrémentale. A titre d’exemple, la flexion d’une poutre encastrée-libre a été étudiée et les résultats améliorent les modèles théoriques. Le modèle éléments finis non-linéaire a été comparé favorablement à un modèle éléments finis coque mince 3D. Une étude paramétrique a été ensuite effectuée. Elle a porté sur l'influence des propriétés mécaniques et sur de la pression de gonflage sur la réponse de la poutre. Les solutions éléments finis linéaires se sont avérées proches des résultats théoriques linéarisés d'une part et les résultats du modèle éléments finis non-linéaire se sont avérés proches des résultats du modèle linéaire dans le cas des propriétés mécaniques élevées alors que le modèle éléments finis non-linéaire est indispensable pour modéliser ces poutres lorsque les propriétés mécaniques du tissu sont faibles / The main objective of this thesis was to model inflatable beams made frorn orthotropic woven fabric composites. The static aspects were investigated in this report. Before planning to develop these models, it was necessary to know all the parameters which have a direct effect on the effective mechanical properties these composites. Thus, a micro­ mechanical model was performed for predicting the effective mechanical properties. The proposed model was based on the analysis of the representative volume element (RVE). The model took into account not only the mechanical properties and volume fraction of each components in the RVE but also their geometry and architecture. Each yarn in the RVE was modelled as a transversely isotropic material (containing fibres and resin) using the concentric cylinders model (CCIVI). A second volumetric averaging which took into account the volume fraction of each constituent (warp yarn, weft yarn and resin), was performed. The model was validated favorably against experimental available data. A parametric study was conducted in order to investigate the effects of various geometrical and mechanical parameters on the elastic properties of these composites. ln the structural analysis, a 3D Timoshenko airbeam with a homogeneous orthotropic woven fabric (OWF) was addressed. The model took into account the geometrical nonlinearities and the inflation pressure follower force effect. The analytical equilibrium equations were performed using the total Lagrangian form of the virtual work principle. As these equations were nonlinear, in a first approach, a linearization was performed at the prestressed reference configuration to obtain the equations devoted to linearized problems. As example, the bending problem was investigated. Four cases of boundary conditions were treated and the deflections and rotations results improved the existing models in the case of isotropic fabric. The wrinkling load in every case was also proposed. In a second approach, the nonlinear equilibrium equations of the 3DTimoshenko airbeam were discretized by the finite element method. Two finite element solutions were then investigated : finite element solutions for linearized problems which were obtained by the means of the linearization around the prestressed reference configuration of the nonlinear equations and nonlinear finite element solutions which were performed by the use of an optimization algorithm based on the Qua.si-Newton method. As an example, the bending problem of a cantilever inflated beam under concentrated load was considered and the deflection results improve the theoretical models. As these beams are made from fabric, the beam models were validated through their comparison with a 3D thin-shell finite element model. The influence of the material effective properties and the inflation pressure on the beam response was also investigated through a parametric study. The finite element solutions for linearized problems were found to be close to the theoretical linearized results. On the other hand, the results for the nonlinear finite element model were shown to be close to the results for the linearized finite element model in the case of high mechanical properties and the non linear finite element model was used to improve the linearized model when the mechanical properties of the fabric are low

Advanced monitoring of the spatio-temporal distribution of process parameters in large-scale vessels and containers such as stirred chemical or bioreactors offers a high potential for the investigation and further optimization of plants and embedded processes. This applies especially to large-scale fermentation biogas reactors where the process performance including the biological processes highly depend on mixing parameters of the complex bio-substrates. Sufficient mixing is a basic requirement for a stable operation of the process and adequate process performance. However, this condition is rarely met in agricultural biogas plants and the process efficiency is often reduced dramatically by inhomogeneities in the agitated vessels. Without a doupt, investigation and monitoring of biochemical parameters, such as the fermentation rate, pH distribution as well as O2 and CO2 concentration is of great importance. Nevertheless, also understanding of non-biological parameters, such as fluid dynamics (flow velocity profiles, circulation times), suspension mixing (homogeneity, location of dead zones and short-circuits) and heat transfer (temperature profiles), is necessary to analyze the impact of mixing on the biological system and also to improve the process efficiency. However, in most industrial scale applications the acquisition of these parameters and their spatial distributions in the large-scale vessels is hampered by the limited access to the process itself, because sensor mounting or cable connections are not feasible or desired. Therefore, state of the art instrumentation of such reactors is commonly limited to few spatial positions where it is doubtfully assumed that the measured parameters are representative for the whole reaction mixture. In this work, a concept of flow following sensor particles was developed. The sensor particles allow long-term measurement of spatially distributed process parameters in the chemically and mechanically harsh environments of agitated industrial vessels. Each sensor particle comprises of an onboard measurement electronics that logs the signals of measurement devices, namely temperature, absolute pressure (immersion depth, axial position) and 3D acceleration. The whole electronics is enclosed in a robust neutrally buoyant capsule (equivalent diameter 58.2 mm; sphericity 0.91), to allow free movement with the flow. The sensor particles were tested in pilot fermenters under comparable flow conditions of biogas fermenters. The experiments proved the applicability of the sensor particles and the robustness to resist the harsh environments of mixing processes. Moreover, the results show the capabilities of the sensor particles to monitor the internal conditions of the vessel correctly and thus deliver significant information about the flow regime. Therefore effects of liquid rheology, vessel geometry, impeller speed and axial impeller position on the macro-mixing process were properly detected. Evaluation of the impeller efficiency and the mixing processes was done based on mixing homogeneity, location of dead zones, axial velocity profiles, circulation time distributions as well as average circulation times, acceleration spectra and temperature profiles that were extracted from the measured data. Furthermore, it is shown, that parameters of mixing models such as circulation number, impeller head, PECLÉT-number and variance of suspended solid particles can be estimated from the measured data. The main achievement of this work is therefore the development and validation of instrumented flow followers for the investigation of macro-mixing effects in agitated vessels. The sensor particles show potential for employment to real applications such as biogas fermenters or large bioreactors and to monitor and improve the mixing and heating regimes.

This document is focused on already existing single-ended frequency filters with modern active components working in current mode and their modification into fully-differential ended form. After the modification both versions were compared between each other. The first part informs about problems concerning analogue frequency filters. The second part deals with used active components - MO-CF (Multiple Output Current Follower), BOTA (Balanced transconductance amplifier), UCC (universal current conveyor), VDTA (Voltage differencing transconductance amplifier), CDTA (Current differencing transconductance amplifier) and VDCC (voltage differencing current conveyor). Four circuits have been chosen and transformed into their differential form. Two circuits have been chosen and realised into PCB and then practicaly measured in a laboratory. The last part is a summary of simulations and measured results and check of circuits behavior result.

This diploma thesis treats the possibilities of the black-white picture depiction in pseudo colors (Pseudocolor). The individual methods, software or hardware are described there and the detailed block scheme of the system Pseudocolor is suggested. The block scheme is created on the basis of gained theoretical knowledge. In the thesis, individual functional blocks of the scheme are described and their circuit designs are realized. Some of the functional blocks are simulated by the PSpice program and accompanied by corresponding signal process data. The suitable choice of the active and passive components is performed, from which the general integration of the system Pseudocolor is made. All the source materials for the realization of the device are given there – double-sided drawing of the printed circuit, layout and specification of the components.

This master’s thesis describes the design of the frequency filters by the help of the graph of the signal flows. There are defined by modern components like GVC (Generalized Voltage Conveyor), GCC (Generalized Current Conveyor), CF (Current Follower), DO-CF (Dual-Output Current Follower), OTA (Operational Transconductance Amplifier), BOTA (Ballanced Operational Transconductance Amplifier) and CFTA (Current Follower Transconductance Amplifier), the graphs of the signal flows, which describe their activity in the thesis. In the other part of the thesis is illustrated the procedure of the design of the frequency filters by the help of the graphs of the signal flows. For the concrete design was selected in the first case as the active component double output current follower and in the second case the CFTA. There are noted all designed circuits of the frequency filters also their characteristic equations in this thesis. The activity of the selected circuits was remitted to the analysis in the simulation program called PSpice. Because the active components, with which was engaged in the design of the filter which doesn’t exist in the real form, that is why the UCC, which is sufficing for attestation of the function of the circuit, was used for the simulation. The simulation was implemented in the frequency range 10 Hz to 10 MHz.

This doctoral thesis is focused mainly on research of new current active elements and their applications in frequency filters suitable for current-mode. Work is focused on design of new filtering structures suitable for traditional single-ended signal processing and also on structures suitable for fully-differential applications. The thesis contains three designed general conceptions of KHN-type second-order filters. Adjustability of quality factor and pole frequency is provided by controllable current amplifiers that are placed properly in designed structures. Structures also contain second-generation current conveyors, multiple-output current followers, transconductance amplifiers and their fully-differential equivalents. There are lot of possible solutions that could be obtained from general structures, some of them are presented in the work. The thesis also presents several multifunctional and also single-purpose filtering structures of second-order and two variants of n-th order synthetic elements which are suitable to realize higher order filters both in single ended and fully differential type. In each case, functionality of new solutions is verified by simulations and in several cases also by real measurement.