Structural behaviour of post-installed reinforcement bars in moment connections of wall-slabs

Post-installed reinforcement (PIR) bars helps to facilitate retrofitting works, mitigate misplaced reinforcement problems, as well as support newly casted additions. However, the use of PIR has not been addressed in the major reinforced concrete (RC) design codes worldwide. Recently, the European standards have introduced a beneficial coefficient of moments in EN 1992-4 2018 for concrete fastenings which allows compliant PIR systems to be designed by using the bonded anchor (BA) design method. However, when applying this method to wall-slab connection design, the moment resisting capacity is often limited by the lack of bar spacing and small concrete covers. This means that the method neglects long embedment depths and the connections designed based on this method are prone to brittle failure. In this paper, the strut and tie model (STM), which can better describe PIR with long embedment depths, together with the fundamental reinforced concrete (RC) theory is used to improve the ductility of moment connections with PIR bars. An experimental study is conducted to explore the structural behaviour of applying PIR bars that connect the wall and slab. Validations on the proposed STM and supplement to the BA design methods are made. From the experimental findings, measures are then proposed to enhance the ductility of the moment connections

Design and installation of post-installed reinforcements: A state-of-the-art review

Post-installed reinforcement (PIR) helps facilitate retrofitting works, mitigate misplaced reinforcement problems, as well as support newly cast concrete members such as modular integrated construction. However, it has not been holistically addressed in major international reinforced concrete (RC) design codes. Nonetheless, based on established design philosophy and associated failure modes, the cast-in reinforcement design method in RC can be extended to design qualified PIR systems. The qualification of PIR system can be referenced to AC 308 (2016), European Assessment Document (EAD) 330087 (2018) and EAD 330499 (2017) in the US and Europe, respectively. In Hong Kong, PIR is conservatively limited to shear connections. Its assumption of pinned connection is less justifiable for some deep sections of beams, which may induce hogging moments, causing tension at the top reinforcement of the supports. In some cases of cantilever slabs, moment connections are necessary to maintain equilibrium. Hence, this paper reviews an up-to-date design methodology and installation guide to complement the Hong Kong Code of Practice for Structural Use of Concrete (HKBD) by referring to the recently published international design codes and documents. The proposal is useful to promote economical, sustainable and technically sound use of PIR system

Integration and Application of a Fiber-Optic Sensing System for Monitoring Debris Flows

This study presents an innovative fiber-optic sensing system for monitoring debris flows. The system mainly comprises an interrogator and four fiber Bragg grating accelerometers. The field tests show that signal-to-noise-ratio (SNR) of the fiber-optic sensor is 10 dB higher than that of a geophone. Following confirmation of the reliability of the proposed sensing system, the systems are deployed along the Ai-Yu-Zi and Chu-Shui Creeks in Nautou County, Taiwan, for monitoring debris flows. The four accelerometers are installed in series. The systems have detected several debris flows in 2012. The monitored data reveal that the frequency range of the acceleration of ground vibration is 10-150 Hz, which is the same as that of the velocity of ground vibration detected by a sensing system that includes geophones. Because the fiber-optic sensing system is more sensitive than the geophone system, the proposed fiber-optic sensing system is highly promising for use in monitoring natural disasters that generate ground vibrations.本研究藉由組合光纖光柵加速度計、解調儀、及其他相關元件，發展一套可偵測土 石流之光纖感測系統。現地測試結果顯示，與目前常用含地聲檢知器的土石流感測系統相較， 本系統所測得地表振動訊號之訊雜比比前者高10 dB。在測試系統量測效能後，將此系統分別 架設於南投縣信義鄉神木村之愛玉子溪及出水溪上。系統中採串連方式配置四個光纖加速度 計，並於2012 年監測到多場土石流。觀測結果顯示，光纖感測系統所測得土石流所造成地表 振動之加速度，與過去地聲檢知器所測得土石流地表振動速度，兩者頻率一樣，均為10–150 Hz。由於光纖光柵加速度計相較於地聲檢知器更為靈敏，因此，除了可應用於偵測土石流外， 也可應用於監測會產生地表振動的其他坡地災害，如：落石及山崩等

Metabolic Syndrome features and risk of neural tube defects

Research articl

Combined distributed turbo coding and space frequency block coding techniques

The distributed space-time (frequency) coding and distributed channel turbo coding used independently represent two cooperative techniques that can provide increased throughput and spectral efficiency at an imposed maximum Bit Error Rate (BER) and delay required from the new generation of cellular networks. This paper proposes two cooperative algorithms that employ jointly the two types of techniques, analyzes their BER and spectral efficiency performances versus the qualities of the channels involved, and presents some conclusions regarding the adaptive employment of these algorithms. © 2010 V. Bota et al.FP7/ICT/2007/21547

Combined distributed turbo coding and space frequency block coding techniques

The distributed space-time (frequency) coding and distributed channel turbo coding used independently represent two cooperative techniques that can provide increased throughput and spectral efficiency at an imposed maximum Bit Error Rate (BER) and delay required from the new generation of cellular networks. This paper proposes two cooperative algorithms that employ jointly the two types of techniques, analyzes their BER and spectral efficiency performances versus the qualities of the channels involved, and presents some conclusions regarding the adaptive employment of these algorithms. © 2010 V. Bota et al.FP7/ICT/2007/21547

Combined distributed turbo coding and space frequency block coding techniques

The distributed space-time (frequency) coding and distributed channel turbo coding used independently represent two cooperative techniques that can provide increased throughput and spectral efficiency at an imposed maximum Bit Error Rate (BER) and delay required from the new generation of cellular networks. This paper proposes two cooperative algorithms that employ jointly the two types of techniques, analyzes their BER and spectral efficiency performances versus the qualities of the channels involved, and presents some conclusions regarding the adaptive employment of these algorithms. © 2010 V. Bota et al.FP7/ICT/2007/21547

An avian influenza A(H11N1) virus from a wild aquatic bird revealing a unique Eurasian-American genetic reassortment

Influenza surveillance in different wild bird populations is critical for understanding the persistence, transmission and evolution of these viruses. Avian influenza (AI) surveillance was undertaken in wild migratory and resident birds during the period 2007–2008, in view of the outbreaks of highly pathogenic AI (HPAI) H5N1 in poultry in India since 2006. In this study, we present the whole genome sequence data along with the genetic and virological characterization of an Influenza A(H11N1) virus isolated from wild aquatic bird for the first time from India. The virus was low pathogenicity and phylogenetic analysis revealed that it was distinct from reported H11N1 viruses. The hemagglutinin (HA) gene showed maximum similarity with A/semipalmatedsandpiper/Delaware/2109/2000 (H11N6) and A/shorebird/Delaware/236/2003(H11N9) while the neuraminidase (NA) gene showed maximum similarity with A/duck/Mongolia/540/2001(H1N1). The virus thus possessed an HA gene of the American lineage. The NA and other six genes were of the Eurasian lineage and showed closer relatedness to non-H11 viruses. Such a genetic reassortment is unique and interesting, though the pathways leading to its emergence and its future persistence in the avian reservoir is yet to be fully established

Status of Muon Collider Research and Development and Future Plans

The status of the research on muon colliders is discussed and plans are outlined for future theoretical and experimental studies. Besides continued work on the parameters of a 3-4 and 0.5 TeV center-of-mass (CoM) energy collider, many studies are now concentrating on a machine near 0.1 TeV (CoM) that could be a factory for the s-channel production of Higgs particles. We discuss the research on the various components in such muon colliders, starting from the proton accelerator needed to generate pions from a heavy-Z target and proceeding through the phase rotation and decay ($\pi \to \mu \nu_{\mu}$) channel, muon cooling, acceleration, storage in a collider ring and the collider detector. We also present theoretical and experimental R & D plans for the next several years that should lead to a better understanding of the design and feasibility issues for all of the components. This report is an update of the progress on the R & D since the Feasibility Study of Muon Colliders presented at the Snowmass'96 Workshop [R. B. Palmer, A. Sessler and A. Tollestrup, Proceedings of the 1996 DPF/DPB Summer Study on High-Energy Physics (Stanford Linear Accelerator Center, Menlo Park, CA, 1997)].Comment: 95 pages, 75 figures. Submitted to Physical Review Special Topics, Accelerators and Beam