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Cette thèse propose une nouvelle approche pour surveiller automatiquementles variations des fréquences et des taux d’amortissement des batiments de grande hauteursoumis à des vibrations ambiantes. L’approche vise à relever simultanément avec les défissuivants: signaux multi-composants enregistrées sur les bâtiments mentionnés ci-dessusavec des réponses impulsionnelles ayant des modes de fréquences rapprochées, des amplitudesfaibles, exponentielles et amorties noyées dans des bruits additifs élevés. La méthoderepose sur l’application de la technique de décrément aléatoire directement sur le signal multicomposantece qui conduit à l’estimation d’une signature de décrément aléatoire multi-modeéquivalente à la réponse impulsionnelle de système. Pour caractériser une telle signature,nous proposons un modèle de signal basé sur la structure physique du bâtiment à partir delaquelle les paramètres modaux peuvent être estimés. Dans le but d’avoir une estimationnon biaisée, nous proposons d’utiliser une méthode itérative sur la base d’une estimation dumaximum de vraisemblance optimisé par une technique de recuit simulé. Afin d’initialiserles paramètres de ce dernier, une première étape est conçu qui peut être considéré commeun estimateur indépendant des paramètres modaux. L’originalité de cette étape réside danssa capacité à définir automatiquement le nombre de modes de la signature estimé grâce àl’utilisation des propriétés statistiques d’un spectre estimé par une transformée de Fourier.Les paramètres modaux estimés par l’étape d’initialisation sont finalement affinés par l’étaped’estimation du maximum de vraisemblance. Celui-ci réduit le biais de l’estimation et donnedes résultats plus fiables et plus robustes. Toutes ces étapes sont définies de manière à être enmesure de surveiller automatiquement l’état de santé d’un bâtiment par l’intermédiaire d’unsuivi long terme en temps réel des variations modales dans le temps sans que l’interventionde l’utilisateur soit nécessaire. En outre, l’approche proposée a accordé une attention touteparticulière à l’estimation automatique du paramètre modal les plus problématique, c’està-dire, le taux d’amortissement. Ces deux caractéristiques sont des atouts originaux parrapport aux techniques existantes. L’adaptabilité et la fonctionnalité de l’AMBA a été validésur six bâtiments réels excités par des vibrations ambiantes. D’après les résultats obtenus,AMBA a prouvé une grande efficacité dans l’estimation automatique des fréquences et destaux d’amortissement dans le cas de modes de fréquences rapprochées et avec un très faiblerapport signal-sur-bruit. AMBA a ainsi démontré une bonne performance pour suivre lesvariations modales au fil du temps. / This thesis proposes a novel approach to automatically monitor the variationsof the frequencies and the damping ratios of actual high-rise buildings subjected to realworldambient vibrations. The approach aims at dealing simultaneously with the followingchallenges: multi-component signals recorded over the aforementioned buildings and havingclosely-spaced frequency modes with low, exponential and damped amplitudes of theirimpulse responses and contaminated with high additive noises. The approach relies on theapplication of the Random Decrement Technique directly over the multi-component signalunder study which leads to the extraction of a Multi-mode Random Decrement Signatureequivalent to the system impulse response. To characterize such a signature, we propose asignal model based on the physical structure of the building from where the modal parameterscan be estimated. For the purpose of non-biased modal estimate, we propose to usean iterative method based on a Maximum-Likelihood Estimation optimized by a simulatedannealing technique. In order to initialize the parameters of the latter, a first step is designedwhich can be considered as an independent estimator of the modal parameters. Theoriginality of this step lies in its ability to automatically define the number of modes of theestimated signature through the use of the statistical properties of a Welch spectrum. Themodal parameters estimated by the spectral-based initialization step are finally refined bythe Maximum-Likelihood Estimation step. The latter reduces the bias in the estimation andyields more reliable and robust results. All these steps are defined in order to be able to automaticallymonitor the health of a building via a long-term real-time tracking of the modalvariations over time without the need to any user intervention . In addition, the proposedapproach has paid very special attention to the automatic estimation of the most problematicmodal parameter, i.e., the damping ratio. Such features making two of the original featuresas compared to existing techniques. The adaptability and functionality of AMBA is validatedover six actual buildings excited by real-world ambient vibrations. From the obtained results,AMBA proved high efficiency in automatically estimating the frequencies and moreover thedamping ratios in case of closely-spaced frequency modes and very low signal-to-noise ratiolevel. AMBA as well demonstrated a good performance for tracking the modal variationsover time.

Time tracking means to record and analyze costs in relation with business output. Managerial time tracking can be characterized as a tool that links working-time recording with planning, approving, rating, billing, invoicing, etc. This thesis deals with theoretical consequences and facts of time tracking approaches, and with practical application of these approaches with the usage of IT time tracking tools. There are described various alternatives of time tracking systems and characterized automatization of business processes with the focus on time tracking business process.

Micro- and nanorobots (MNRs) are small autonomous devices capable of performing complex tasks and have been demonstrated for a variety of non-invasive biomedical applications, such as tissue engineering, drug delivery or assisted fertilization. However, translating such approaches to an in vivo environment is critical. Current imaging techniques do not allow localization and tracking of single or few micromotors at high spatiotemporal resolution in deep tissue. This thesis addresses some of these limitations, by exploring the use of two optical-based techniques (IR and photoacoustic imaging (PAI)) and a combination of both US and PAI. First, we employ an IR imaging setup to visualize mobile reflective micromotors under scattering phantoms and ex vivo mouse skull tissues, without using any labels. The reflective micromotor reflects more than tenfold the light intensity of a simple particle. However, the achieved penetration depth was ca. 100 μm (when using ex vivo tissues), limiting this technique to superficial biomedical applications. In this regard, PAI plays a role that combines the advantages of US such as penetration depth and real-time imaging with the molecular specificity of optics. For the first time, in this thesis, this method is evaluated for dynamic process monitoring, in particular for tracking single micromotor in real-time below ~1 cm deep phantom and ex vivo tissue. However, the precise function control of MNRs in living organisms, demand the combination of both anatomical and functional imaging methods. Therefore, in the end, we report the use of a hybrid US and PA system for the real-time tracking of magnetically driven micromotors (single and swarms) in phantoms, ex vivo, and in vivo (in mice bladder and uterus), envisioning their application for targeted drug-delivery. This achievement is of great importance and opens the possibilities to employ medical micromotors in a living organism and perform a medical task while being externally controlled and monitored.:ABSTRACT 1 1 INTRODUCTION 5 1.1 Motivation 5 1.2 Background 7 1.2.1 Microrobotics 7 1.2.2 Medical Imaging 9 1.3 Objectives and Structure of Thesis 12 2 FUNDAMENTALS 15 2.1 Optical Imaging 15 2.1.1. Reflection-based Imaging 17 2.1.2. Fluorescence-based Imaging 18 2.1.1 Light-Tissue Interaction 20 2.2 Photoacoustic Imaging 23 2.2.1 Theory 23 2.2.2 Implementation 25 2.3 Ultrasound Imaging 26 2.3.1 Theory 26 2.3.2 Implementation 28 3 MATERIALS AND METHODS 30 3.1 Fabrication of Magnetic Micropropellers 30 3.1.1 3D Laser Lithography of Polymeric Resin 30 3.1.2 Self-assembly of SiO2 Particles 31 3.1.3 Electron Beam Evaporation 32 3.1.4 Surface Functionalization 33 3.2 Fabrication of Phantom Tissue and Microfluidic Channels 34 3.2.1 Fabrication of PDMS-Glycerol Phantom 34 3.2.2 Fabrication of Agarose Phantom 35 3.2.3 Phantom based on Ex vivo Tissues (Chicken Breast and Mice Skull) 36 3.2.4 Microfluidic Channel Platform 37 3.3 Sample Characterization 38 3.3.1 Optical Microscopy 38 3.3.2 Scanning Electron Microscopy 38 3.4 Magnetic Actuation 39 3.4.1 Magnetic Force 39 3.4.2 Magnetic Torque 39 3.5 Ethic Statement for Mice Experiments 41 4 OPTICAL IMAGING OF MICROROBOTS 42 4.1 Concept of Reflective Micromotors 42 4.2 Fabrication of Reflective Micromotors 44 4.3 IR Imaging Actuation Setup 45 4.4 Actuation and Propulsion Performance below Phantom 47 4.5 Actuation and Propulsion Performance below Ex Vivo Skull Tissue 50 4.6 Actuation and Propulsion Performance in Blood 51 5 PHOTOACOUSTIC IMAGING OF MICROROBOTS 55 5.1 Absorbers for Deep Tissue Imaging 55 5.2 Absorber Micromotor Design and Fabrication 56 5.3 Photoacoustic Imaging Setup 58 5.4 Actuation Performance below Phantom Tissue 60 5.5 Actuation Performance below Ex Vivo Tissue 65 6 HYBRID ULTRASOUND AND PHOTOACOUSTIC IMAGING 67 6.1 Hybrid Ultrasound/Photoacoustic System 68 6.2 Fabrication and Characterization of Micromotors 69 6.3 Actuation and Propulsion Performance below Phantom 69 6.4 Actuation and Propulsion Performance below Ex Vivo Tissues 71 6.5 Actuation and Propulsion Performance in Mice 72 6.5.1 Swimming of Micromotors in Bladder 72 6.5.2 Actuation of Micromotors in Uterus 74 6.5.3 3D Multispectral Imaging 76 6.5.4 Towards Targeted Drug Delivery 77 7 SUMMARY AND PERSPECTIVES 80 7.1 Summary 80 7.2 Future Perspectives 83 7.2.1 Contrats Enhancing Labels 84 7.2.2 Novel Imaging Concepts 85 8 REFERENCES 88 9 APPENDIX 105 List of Figures 105 List of Tables 107 Abbreviations 108 List of Publications 109 Acknowledgements 110 Selbstständigkeitserklärung 111 Curriculum Vitae 112

Medical micromotors have the potential to lead to a paradigm shift in future biomedicine, as they may perform active drug delivery, microsurgery, tissue engineering, or assisted fertilization in a minimally invasive manner. However, the translation to clinical treatment is challenging, as many applications of single or few micromotors require real-time tracking and control at high spatiotemporal resolution in deep tissue. Although optical techniques are a popular choice for this task, absorption and strong light scattering lead to a pronounced decrease of the signal-to-noise ratio with increasing penetration depth. Here, a highly reflective micromotor is introduced which reflects more than tenfold the light intensity of simple gold particles and can be precisely navigated by external magnetic fields. A customized optical IR imaging setup and an image correlation technique are implemented to track single micromotors in real-time and label-free underneath phantom and ex vivo mouse skull tissues. As a potential application, the micromotors speed is recorded when moving through different viscous fluids to determine the viscosity of diverse physiological fluids toward remote cardiovascular disease diagnosis. Moreover, the micromotors are loaded with a model drug to demonstrate their cargotransport capability. The proposed reflective micromotor is suitable as theranostic tool for sub-skin or organ-on-a-chip applications.

Accurately tracking employee work hours is a vital aspect of managing any organization, regardless of its size. Time reporting serves as a valuable source of information for management teams, enabling them to effectively plan and manage projects, allocate resources, monitor budgets, and track overall productivity. It is an essential component of workforce management that assists companies in making informed decisions regarding scheduling, employee compensation, and resource allocation. Time reporting is an important task for companies. However, the process of time reporting can often be cumbersome and time-consuming for employees. Typically, employees are required to log in to a web application and manually input their work hours, vacation days, and sick leaves. This process can be complicated and prone to errors. To simplify this process, an innovative solution was developed using Information Technology. The solution involved the creation of a Slack bot, which is a chat-bot that can communicate with employees and gather time reporting data automatically. This bot can be integrated with a company’s existing communication tools, allowing employees to report their work hours, vacation days, and sick leaves in real-time using a simple chat interface. The bot can also provide reminders to employees to submit their time reports, reducing the chances of delayed submissions. / Att noggrant spåra anställdas arbetstid är en viktig aspekt av att leda alla organisationer, oavsett dess storlek. Tidsrapportering fungerar som en värdefull informationskälla för ledningsgrupper, vilket gör det möjligt för dem att effektivt planera och hantera projekt, allokera resurser, övervaka budgetar och spåra den totala produktiviteten. Det är en viktig komponent i personalledning som hjälper företag att fatta välgrundade beslut om schemaläggning, ersättning till anställda och resursallokering. Tidsrapportering är en viktig uppgift för företag. Processen med tidsrapportering kan dock ofta vara krånglig och tidskrävande för de anställda. Vanligtvis måste anställda logga in på en webbapplikation och manuellt mata in sina arbetstimmar, semesterdagar och sjukskrivningar. Denna process kan vara komplicerad och risk för fel. För att förenkla denna process utvecklades en innovativ lösning med hjälp av informationsteknologi. Lösningen innebar skapandet av en Slack-bot, som är en chat-bot som kan kommunicera med anställda och samla in tidsrapporteringsdata automatiskt. Denna bot kan integreras med ett företags befintliga kommunikationsverktyg, så att anställda kan rapportera sina arbetstimmar, semesterdagar och sjukskrivningar i realtid med hjälp av ett enkelt chattgränssnitt. Boten kan också ge påminnelser till anställda att skicka in sina tidsrapporter, vilket minskar risken för försenade inlämningar.

On-the-job injuries that occur even after implementing safety interventions highlight the need for identifying the limitations in them and for making future safety interventions and technological advances more effective. One possible reason for this lower-than-expected-safety returns is the latent side-effect of safety interventions, known as risk compensation. This dissertation aimed to provide empirical evidence and theoretical considerations of risk compensation effect in the construction industry. Accordingly, a multi-sensor immersive mixed-reality environment consists of a virtual projection of the environment and passive haptics of a roof was developed to study risk compensation among residential roofers. Simulating height, environmental factors (wind and sound), passive haptic, and virtual falls stimulated sufficient Sense of Presence to trigger subjects' behavioral changes while installing shingles on a 27-degree sloped roof under three levels of safety interventions (i.e., with no fall-safety intervention, with an injury-reducing fall-safety intervention—i.e., fall-arrest system—and with an injury-preventing fall-safety intervention— i.e., a fall-arrest system and a guardrail). The baseline demographic, psychographic, and cognitive measures combined with real-time tracking and wearable sensors provided an opportunity to track the worker's motions, localize his/her position, obtain real-time musculoskeletal data, and monitor the his/her behavioral and physiological responses. The collected data is then translated into information about the risk perception and risk-taking behavior of the worker. The results yielded unequivocal evidence of risk compensation—the lower perceived risk associated with the situation (lower levels of stress) and the false sense of security among roofers when they were provided with safety interventions apparently encouraged them to be less cautious by leaning over the edge, stepping closer to the roof edge, spending more time exposing themselves to fall risk, over-relying on the safety equipment through different facing directions and choices of posture stability. As a result, they also experienced more near-misses (close calls). This behavioral adaptation was more pronounced when they were provided with an injury-preventing safety intervention (e.g., guardrail). The findings also suggested that the productivity and safety benefits of safety interventions can be negated due to risk compensation, which identifies vital information for the construction-safety community to consider during the design and implementation of more effective safety interventions and technological advances. Roofers with high risk tolerance and sensation seekers were identified as high-risk groups who are more likely to be involved in risk-compensatory behaviors; various behavioral interventions are suggested in this dissertation to counteract excessive risk-taking and to reduce risk compensation. The findings of this study shed light on the question of why injury rates have remained at worrisome levels despite advances in protective measures and interventions. In the long-term, a better understanding of risk compensation will translate into fundamental knowledge about how the construction industry should approach and maintain controls after safety interventions. / Doctor of Philosophy / While researchers have dispensed considerable efforts to reduce the risk of occupational injuries by implementing safety interventions, the large number of safety incidents occurring each year in the construction industry. It is hypothesized that the latent effect of safety interventions, known as risk compensation, might be a possible reason why many of the safety interventions and technological advances have not fully achieved their safety objectives. This dissertation aimed to empirically examine the changes in workers' productivity, risk perception, risk-taking behaviors as a function of different safety interventions in place. To study this within a risk-free setting, an immersive mixed-reality environment simulating roofing task was developed. Then, the reactionary behavioral responses of participants were monitored using real-time tracking sensors and qualitative sources of data while they were completing a roofing task under three counterbalanced levels of safety interventions (i.e., with no fall-safety intervention, with an injury-reducing fall-safety intervention—i.e., fall-arrest system—and with an injury-preventing fall-safety intervention— i.e., a fall-arrest system and a guardrail). The findings indicated that the reduced perceived risk and the desire for increased productivity may skew risk analysis and strongly bias workers toward presuming invulnerability when safety interventions are in place. According to risk compensation theory, workers' risk tolerance and perceptions of risk influence their risk-taking behavior—as the perceived risk associated with the situation decreases, individuals take more risks to achieve a level of risk they can comfortably tolerate. Therefore, the workers might become less cautious by leaning over the edge, stepping closer to the roof edge, spending more time exposing themselves to fall risk, over-relying on the safety equipment through different facing directions and choices of posture stability. This result does not necessarily imply the safety innovations are completely ineffective, but rather demonstrates dangers users face when they misperceive the effectiveness of a safety intervention. Furthermore, roofers with high risk tolerance and a high sensation-seeking disposition were identified as high-risk groups who are more likely to be involved in risk-compensatory behaviors. This research represented a substantive departure from the status quo by proposing novel pathways for proactive incident prevention due to risk compensation in the construction industry. The contribution of this study is especially significant because a better understanding of risk compensation will translate into fundamental knowledge about how the construction industry should approach and maintain controls after safety interventions.

近年來越來越多虛實整合技術不斷地湧出，像是電影阿凡達或虛實互動型態的表演。這樣的表演會根據事先預錄好的虛擬角色進行演出，但要成功地演出需要演員們不斷的練習。另外,許多電影利用攝影機捕捉人體姿態來與虛擬角色互動，但此方法受限於燈光環境以及障礙物。 此篇論文運用穿戴式裝置與新一代無線網路藍芽4.0,提出即時追蹤技術套用於這類表演,可使得演出更加豐富並且能即興創作。然而，目前受限於穿戴式平台上的藍芽訊號強度更新頻率每秒只有5至10次且傳輸容量有限，所以本篇論文結合體態感測裝置輔助無線網路藍芽4.0,提升對穿戴者的即時追蹤能力。實驗結果與真實位置只有0.3至0.5秒的延遲時間,並在校內進行兩場互動式展演作驗證成果。未來期許可以將此技術運用於多人展演場，讓更多使用者可以互動體驗。 / Recently, more and more interactive performance technologies appear such as Avatar or virtual-character integrated art perform. Such performs are based on pre-made animations and physics simulations. However, this kind of shows need a lot of practice, and it is impossible that audience or performers play with or interact with the virtual characters. In addition, many moviemakers use high quality cameras to distinguish body postures. Although cameras can record anything with high precision, it is constrained on the light and obstacles of the environments. If we, somehow, can capture the motion of the performers in real time, then we are able to interact with virtual characters and make improvisation possible. This thesis aims to use the wearable sensors and the Received Signal Strength Indication (RSSI) of BLE to track in real-time. However, the update rate of RSSI is limited to 5~10 per second. This thesis proposed a tracking technique which combines with wearable motion sensors to assist BLE localization. The tracking lag can be reduced to only 0.3~0.5 seconds, and also real performance was experimented in the campus. In the future, we hope to use this technique on interactive performance with many people in different places.

Sledování obecného objektu na zařízení s omezenými prostředky v reálném čase je obtížné. Mnoho algoritmů věnujících se této problematice již existuje. V této práci se s nimi seznámíme. Různé přístupy k této problematice jsou diskutovány včetně hlubokého učení. Představeny jsou reprezentace objektu, datasety i metriky pro vyhodnocování. Mnoho sledovacích algorimů je představeno, osm z nich je implementováno a vyhodnoceno na VOT datasetu.

近年來穿戴相關發展越來越蓬勃，特別是在虛擬-實境的綜合藝術表 演中，例如: 電影「猩球崛起」。然而大部分虛擬實境的綜合內容是 基於腳本預先錄製好的，而且演員需要大量的練習，使表演能夠完美 演出。此外，如果我們想要在兩人的相對方向定位上有特殊效果，那 麼預先錄製的的方法是不合適的。解決這個問題的一個方法是，使用 高品質的相機偵測身體的姿勢或位置。但是精准度常會受限於光線或 是障礙物。 本篇論文中，我們提出一個即時相對方向定位方法，這方法使用無線 可穿戴式設備解決這個問題。我們結合BLE 所發送的Received Signal Strength Indicator (RSSI)與IMU 感測器資訊，來追蹤兩個表演者的相對方向定位的位置。但是RSSI 資料有波動與不穩定性、IMU 會引起 累積的誤差。我們發明了「可靠程度」的RSSI 量測概念，並且把這 概念運用在IMU 定期校正上。我們實驗的情況是，兩個人的舞蹈來 驗證準確性，結果是令人滿意的。我們還使用Unity 來實踐人體骨架， 以便與兩個舞者動作做比較。在未來，我們開發的方案可以用於藝術 表演，使內容更豐富，更具互動性。 / In recent years, wearable-related applications are flourishing, especially in virtual-real integrated art performance, such as “Rise of the Planet of the Apes”. However, most of the virtual-real integrated contents are pre-recorded based on the script, and the performer needs a lot of practice to make the integration perfect. Moreover, if we want to make special effect based on the relative directional positions of two performers, the pre-recorded approach is not suitable. One way to tackle this problem is to use the high-quality camera to detect the body posture or position.But the accuracy is usually limited in light intensity or obstacles. In this thesis, we propose a real-time relative directional positioning approach using wireless wearable devices to solve this problem. We use Received Signal Strength Indicator (RSSI) of BLE, combined with IMU sensors to track two performers’ relative directional positions. The RSSI fluctuates and the IMU causes accumulated errors. We invent the concept of “reliable level” of RSSI measures to periodically correct the IMU errors. We experiment the scenario of two-person dance to validate the accuracy, and the result is satisfactory. We also use Unity to real-time render the human skeleton for comparison with the two dancers’ motion.In the future, our developed scheme can be used in the art performance to make the content richer and more interactive.