PERFORMANCE-BASED ENGINEERING FOR EVALUATION AND RETROFITTING NON-DUCTILE REINFORCED CONCRETE BUILDINGS INCORPORATING AFTERSHOCK HAZARD

Performance-based engineering (PBE) provides a probabilistic tool for assessing the seismic risk and performance of buildings. Only the mainshock hazard has been included in the current PBE framework, although the concern on aftershock hazard has been increased recently. This study develops methodologies to incorporate aftershock hazard into a PBE framework, and assesses the seismic risk and performance of non-ductile reinforced concrete (RC) frame buildings under mainshock and aftershock hazards. A seismic retrofit strategy for these buildings, base isolation, is also evaluated using the developed methodologies. A methodology for synthesizing aftershock ground motions is proposed and validated to resolve the challenge imposed by limited aftershock records. Seismic risks for two nonductile RC frame buildings representing low-rise and mid-rise buildings are examined. Results show that aftershocks can increase structural responses and seismic risk. Based on the state-of-the-art mainshock-based performance assessment methodologies, a new assessment methodology is developed with incorporation of aftershock hazard. The interactive effects between a variety of post-quake decisions and aftershocks are also considered. The proposed methodology is utilized to estimate the direct loss, downtime, and fatalities for two RC frame buildings under MS-AS sequences. Results suggest that aftershocks can cause significant additional seismic loss. The characteristics of MS-AS sequences that may be the cause of the aftershock-induced additional consequence in terms of loss, downtime, and fatalities are discussed and identified through a statistical analysis. The important sources of uncertainty of post-quake decisions are also investigated though a sensitivity study. A comparative study is also performed for a RC frame building before and after being retrofitted with base isolation to determine the risk mitigation due to base isolation. The seismic risk is found to be effectively reduced by base isolation. The effect of various sources of uncertainties in the base isolation system are investigated through a sensitive study using mainshock-aftershock (MS-AS) ground motions at a variety of intensity levels. The most important uncertainty sources are identified. Life-cycle cost-benefit analysis is also performed for the two RC frame buildings to evaluate the economical effectiveness of adopting base isolation as a seismic retrofit strategy with consideration of mainshock and aftershocks. It is revealed that the benefit from base isolation can outweigh the additional cost for buildings in regions with high seismicity, and that the benefit is more significant when aftershocks are considered. The influence of aftershocks and base isolation on the structural robustness is investigated. Limitations and future works are also presented

Steroid-Based Supramolecular Systems and their Biomedical Applications: Biomolecular Recognition and Transportation

In this chapter, the biomedical application of steroid-based compounds at “beyond the molecule”—supramolecular level—is reviewed. The renewable and economic natural steroid compounds could be employed as building blocks in the design and construction of steroid-based supramolecular systems. The specific physicochemical features (size, shape, topology, hydrophobicity, chemical modifiability, etc.) and biological properties (biocompatibility, biodegradability, bioaffinity, etc.) could be integrated into functional supramolecular systems by chemical synthesis, modification and intermolecular interactions (such as hydrogen bonding, π-π stacking, van der Waals forces, inclusion interactions, chiral interactions, electrostatic interactions, and so on). The steroid-based (supra)molecules could be employed for molecular recognition and/or be self-assembled into various functional supramolecular assemblies for biomedical applications. The specific physicochemical and biological properties, good biocompatibility, and biological activity endow the steroid-based supramolecular systems good feasibility to be employed in biomolecular recognition/sensing and biomolecular transportation (gene/drug delivery). The examples in this chapter are exemplificative of the transformation of natural steroid-based compounds into functional steroid-based supramolecular systems through molecular and supramolecular engineering technology, moreover, which may inspire the systematic study of natural product-based supramolecular (nano)materials toward future pharmaceutical and biomedical industry

Cultural realism : strategic culture and grand strategy in Chinese history. Princeton: Princeton University Press, 1995. (Johnston, Alastair Iain)

從事戰略文化研究的學者相信，戰略除了是一個現實政治的課題，也是一 個文化的課題。二千多年來，戰略深深地植根於人類的文化傳統中，受到意識 形態、價值體系等種種文化要素的薰陶，而其本身也變成了文化傳統的一部分。 基於戰略行為受到文化要素的影響，戰略取向亦早已成為文化傳統的一部分， 戰略決策不可能完全理性，祇能在特定的文化背景被認為理性。對於某個民族 來說是完全理性的行為，對於具有不同文明背景的對手來說可能是愚不可及， 或完全無法理解的瘋狂行為。不同文明的接觸激化戰略思維中價值體系的互動， 也成為戰略文化硏究的理想素材。冷戰時期成為戰略文化研究的溫床，學者相 信美國和蘇聯的戰略取向都各自受到本身文化價值所影響，形成鮮明對比。例 如蘇聯的戰爭方式偏好於先制攻擊|而美國在運用武力時則懷有十字軍的情意 結。至於中國的戰略文化，則被形容為政治對武力的維制，企圈以盡量微量的 軍事力量解決衝突。近十年來，學者在歷史上找到更多素材加以研究，尤其是 分析不同文明和價值體系接觸的時候產生具爭議性，或看似非理性的行徑，運 用戰略文化角度來觀察較能凸顯歷史和文化的特質。至於研究的角度也深化到 討論不同文化對暴力的不同制約，社會規範對軍事力量的模塑，和意識形態對 戰略取向的界定等問題

High-throughput intensity diffraction tomography with a computational microscope

We demonstrate a motion-free intensity diffraction tomography technique that enables direct inversion of 3D phase and absorption from intensity-only measurements for weakly scattering samples. We derive a novel linear forward model, featuring slice-wise phase and absorption transfer functions using angled illumination. This new framework facilitates flexible and efficient data acquisition, enabling arbitrary sampling of the illumination angles. The reconstruction algorithm performs 3D synthetic aperture using a robust, computation and memory efficient slice-wise deconvolution to achieve resolution up to the incoherent limit. We demonstrate our technique with thick biological samples having both sparse 3D structures and dense cell clusters. We further investigate the limitation of our technique when imaging strongly scattering samples. Imaging performance and the influence of multiple scattering is evaluated using a 3D sample consisting of stacked phase and absorption resolution targets. This computational microscopy system is directly built on a standard commercial microscope with a simple LED array source add-on, and promises broad applications by leveraging the ubiquitous microscopy platforms with minimal hardware modifications

Auction Design for Value Maximizers with Budget and Return-on-spend Constraints

The paper designs revenue-maximizing auction mechanisms for agents who aim to maximize their total obtained values rather than the classical quasi-linear utilities. Several models have been proposed to capture the behaviors of such agents in the literature. In the paper, we consider the model where agents are subject to budget and return-on-spend constraints. The budget constraint of an agent limits the maximum payment she can afford, while the return-on-spend constraint means that the ratio of the total obtained value (return) to the total payment (spend) cannot be lower than the targeted bar set by the agent. The problem was first coined by [Balseiro et al., EC 2022]. In their work, only Bayesian mechanisms were considered. We initiate the study of the problem in the worst-case model and compare the revenue of our mechanisms to an offline optimal solution, the most ambitious benchmark. The paper distinguishes two main auction settings based on the accessibility of agents' information: fully private and partially private. In the fully private setting, an agent's valuation, budget, and target bar are all private. We show that if agents are unit-demand, constant approximation mechanisms can be obtained; while for additive agents, there exists a mechanism that achieves a constant approximation ratio under a large market assumption. The partially private setting is the setting considered in the previous work [Balseiro et al., EC 2022] where only the agents' target bars are private. We show that in this setting, the approximation ratio of the single-item auction can be further improved, and a $\Omega(1/\sqrt{n})$-approximation mechanism can be derived for additive agents.Comment: 29 page

The protein C system in cutaneous wounds and burns

Cutaneous wound healing is a ubiquitous experience. Our largest organ provides a vital protective role in our interactions with an often-hostile environment. Any compromise in its integrity is restored with a coordinated cascade of events – haemostasis, inflammation, proliferation, and remodelling – that is sophisticated in its complexity, yet tantalising in its desire to be tamed by science. An understanding of these predictable phases of physiological healing has led to revelations of rogue processes such as unbridled inflammation that give rise to nonhealing wounds, or even cancer. Our best efforts at manipulating the wound microcosm have yielded several promising targets. Of the few biological agents that have progressed to clinical trials, activated protein C (APC) has consistently exhibited robust healing capacity in case studies and a randomised clinical trial. Upon activation from its zymogen protein C (PC), APC serves as a well-known anticoagulant. More recently, and of particular relevance in complex processes such as wound healing, it has demonstrated pleiotropic cytoprotective properties including anti-inflammatory actions, anti-apoptosis, and endothelial and epithelial barrier stabilisation. To circumvent potential bleeding side effects, a bioengineered variant called 3K3A-APC was synthesised with minimal anticoagulant activity in vivo, and has primarily been examined for its neuroprotective activity. However it has not been tested in cutaneous wounds, which thus constitutes the first aim of this project. This thesis presents several salient findings for 3K3A-APC as a topical wound healing agent in preclinical studies. 3K3A-APC promoted a healing phenotype in major skin cell types in culture (endothelial cells, fibroblasts, and keratinocytes), and reduced time to complete healing in mouse wounds by around three days (p < 0.0005), in a similar manner to APC. Its efficacy was then confirmed in pig wounds which more closely mimic human skin. Kaplan-Meie..

Machine Learning Methods for Autonomous Object Recognition and Restoration in Images

Image recognition and image restoration are important tasks in the field of image processing. Image recognition are becoming very popular due to the state-of-the-art deep learning methods. However, these models usually require big datasets and high computational costs, which could be challenging. This thesis proposes an online learning framework that deals with both small and big datasets. For small datasets, a Cauchy prior logistic regression classifier is proposed to provide a quick convergence, and the online weight updating scheme is efficient due to the previously trained weights being reused. For big datasets, convolutional neural network could be implemented. For image recognition, non-parametric classifiers are often used for image recognition such as K-nearest neighbours, however, K-nearest neighbours are vulnerable to noise and high dimensional features. This thesis proposes a non-parametric classifier based on Bayesian compressive sensing; the developed classifier is robust and it does not need a training stage. For image restoration, which is usually performed before image recognition as a preprocessing process. This thesis proposes such a joint framework that performs image recognition and restoration simultaneously. In image restoration, image rotation and occlusion are common problems but convolutional neural networks are not suitable to solve these due to the limitation of the convolutional process and pooling process. This thesis develops a joint framework based on capsule networks. The developed joint capsule framework could achieve a good result on recognition, image de-noising, recovering rotation and removing occlusion. The developed algorithms have been evaluated for vehicle logo restoration and recognition, however, they are transferable to other implementations. This thesis also developed an automatic detection and recognition framework for badger monitoring for the first time. Badger plays a key role in the transmission of bovine tuberculosis, which is described by government as the most pressing animal health problem in the UK. An automatic badger monitoring system could help researcher to understand the transmission mechanisms and thereby to develop methods to deal with the transmission between species

Development and characterization of high-k dielectric/germanium gate stack

Ph.DDOCTOR OF PHILOSOPH