301 research outputs found

    Non-Negative Skin Friction Piles in Layered Soil

    Get PDF
    A project in which a special type of steel pipe piles which reduce negative skin friction is described. The piles are driven in a layered soil which is subjected to subsidence due to pumping. The design concept in assessing the pile length, carrying capacity, settlement, construction control and load tests under these special conditions are discussed

    Instrumentation of a Sewer Tunnel in Weak Singapore Soils

    Get PDF
    The effects of tunnelling in soft ground consisting mainly of Singapore marine clay were recently monitored to establish ground response characteristics. A sewer tunnel of 2.1 m square section was driven at a depth of 6.3 m in this soil by jacking conventional shield and face supports against installed timber lining. Ground response was monitored by an assortment of field instruments read over several weeks\u27 duration. Peck\u27s proposal (1969) of fitting a normal distribution profile to lateral surface settlement field plots when a heading is well past, and the suggestion by Oshikoshi et al 0978) that similar profiles may be drawn across an error function fitted to longitudinal surface settlement field plots, have been confirmed for the site. In addition, similar relationships to the above were found to apply with depth. Thus, taking into account Lo\u27 s (1982) determination of standard deviation and ground loss volume for marine clay based on the relationships proposed by Peck (1969) and Yoshikoshi et al (1980), it should, in principle, be possible to determine the vertical ground displacement pattern associated with any tunnel excavation in this soil

    Values and Diversity of Organisational Work Ethicality: Lessons Learnt from Sri Lankan Entrepreneurs

    Get PDF
    The aim of this paper is to examine values as a component of organisational work ethicality, uncovering the contextual realities of values and explore the diversity of work ethicality in the entrepreneurial context in Sri Lanka. Organisational work ethicality is explained through egoistic work ethicality, utilitarian work ethicality and deontological work ethicality. With a view to get a deeper understanding of the diversity of organisational work ethicality, a qualitative approach is adopted. Twelve entrepreneurs were selected for in-depth interviews. A thematic analysis was carried out for field notes with the support of NVivo 6 version. Findings of this study reveal that the entrepreneurial thinking and their interpretations derived different social meanings of organisational work ethicality. The final outcome shows that rather than single dominant work ethicality, a combination of work ethicalities was preferred by most of the entrepreneurs. Within this mix of ethicalities, deontological ethicality and egoistic work ethicality seem to be equally practised by the entrepreneurs. The utilitarian ethicality seems to be practised at a minimum level. As a result, the implicational value of this study lies on at the organisational level and policy making level to rethink and reestablish a mechanism to improve ethical aspects of the businesses in order to maximise social well-being while doing the right things for the society and strengthening shareholders’ protection. KeywordsBusiness Ethics, Business Practices, Deontological Work Ethicality,Egoistic Work Ethicality, Entrepreneur, Utilitarian Work Ethicality, Value

    Scale up your In-Memory Accelerator: Leveraging Wireless-on-Chip Communication for AIMC-based CNN Inference

    Get PDF
    Analog In-Memory Computing (AIMC) is emerging as a disruptive paradigm for heterogeneous computing, potentially delivering orders of magnitude better peak performance and efficiency over traditional digital signal processing architectures on Matrix-Vector multiplication. However, to sustain this throughput in real-world applications, AIMC tiles must be supplied with data at very high bandwidth and low latency; this poses an unprecedented pressure on the on-chip communication infrastructure, which becomes the system's performance and efficiency bottleneck. In this context, the performance and plasticity of emerging on-chip wireless communication paradigms provide the required breakthrough to up-scale on-chip communication in large AIMC devices. This work presents a many-tile AIMC architecture with inter-tile wireless communication that integrates multiple heterogeneous computing clusters, embedding a mix of parallel RISC-V cores and AIMC tiles. We perform an extensive design space exploration of the proposed architecture and discuss the benefits of exploiting emerging on-chip communication technologies such as wireless transceivers in the millimeter-wave and terahertz band

    In situ 4D tomography image analysis framework to follow sintering within 3D-printed glass scaffolds

    Get PDF
    We propose a novel image analysis framework to automate analysis of X-ray microtomography images of sintering ceramics and glasses, using open-source toolkits and machine learning. Additive manufacturing (AM) of glasses and ceramics usually requires sintering of green bodies. Sintering causes shrinkage, which presents a challenge for controlling the metrology of the final architecture. Therefore, being able to monitor sintering in 3D over time (termed 4D) is important when developing new porous ceramics or glasses. Synchrotron X-ray tomographic imaging allows in situ, real-time capture of the sintering process at both micro and macro scales using a furnace rig, facilitating 4D quantitative analysis of the process. The proposed image analysis framework is capable of tracking and quantifying the densification of glass or ceramic particles within multiple volumes of interest (VOIs) along with structural changes over time using 4D image data. The framework is demonstrated by 4D quantitative analysis of bioactive glass ICIE16 within a 3D-printed scaffold. Here, densification of glass particles within 3 VOIs were tracked and quantified along with diameter change of struts and interstrut pore size over the 3D image series, delivering new insights on the sintering mechanism of ICIE16 bioactive glass particles in both micro and macro scale

    Thermal Conductivity Enhancement of Al2O3 Nanofluid in Ethylene Glycol and Water Mixture

    Get PDF
    AbstractThe ability of nanofluids that exhibits enhanced thermal performance is acknowledged by researchers through studies since decades ago. However, the observation of thermal properties for nanofluids in water and ethylene glycol based is not fully explored yet. Hence, this paper presents the thermal conductivity of water and ethylene glycol (EG) based Al2O3 nanofluid. The 13 nm sized Al2O3 nanoparticles were dispersed into three different volume ratio of water: EG such as 40:60, 50:50 and 60:40 using a two-step method. The measurement of thermal conductivity was performed using KD2 Pro Thermal Properties Analyzer at working temperatures of 30 to 70 ĚŠC for volume concentration of 0.5 to 2.0%. The results indicate that the thermal conductivity increases with the increase of nanofluid concentration and temperature. While the percentage of ethylene glycol increase, the range of thermal conductivity decreases due to ethylene glycol properties. The measurement data of the nanofluids give maximum enhancement of thermal conductivity at condition 2.0% volume concentration, temperature of 70 ĚŠC and for all base fluid

    Detection and tracking volumes of interest in 3D printed tissue engineering scaffolds using 4D imaging modalities.

    Get PDF
    Additive manufacturing (AM) platforms allow the production of patient tissue engineering scaffolds with desirable architectures. Although AM platforms offer exceptional control on architecture, post-processing methods such as sintering and freeze-drying often deform the printed scaffold structure. In-situ 4D imaging can be used to analyze changes that occur during post-processing. Visualization and analysis of changes in selected volumes of interests (VOIs) over time are essential to understand the underlining mechanisms of scaffold deformations. Yet, automated detection and tracking of VOIs in the 3D printed scaffold over time using 4D image data is currently an unsolved image processing task. This paper proposes a new image processing technique to segment, detect and track volumes of interest in 3D printed tissue engineering scaffolds. The method is validated using a 4D synchrotron sourced microCT image data captured during the sintering of bioactive glass scaffolds in-situ. The proposed method will contribute to the development of scaffolds with controllable designs and optimum properties for the development of patient-specific scaffolds

    Eco-Friendly Alternatives for Storage Pest Management:Leaves of Ruta Graveolens (Aruda) as a Repellent Against the Rice Weevil, Sitophilus Oryzae L.

    Get PDF
    In view of worldwide interest and greater public awareness in finding plant products as the most promising and ecologically safer alternatives for synthetic insecticides in post-harvest protection of stored rice, present study was undertaken to explore the potential of leaves of Ruta graveolens (Aruda) as a repellent against S.oryzae infestations. Leaf powder and solvent extracts of R. graveolens were evaluated for their contact and fumigant repellent properties against seven day old S. oryzae adults. In contact repellency test, weevils (20 each) were exposed to 1.0 g, 3.0 g, 5.0 g, and 7.0 g of leaf powder mixed with white raw rice grains in a modified cup bioassay apparatus. Fumigation repellency of leaf powder was tested using same dosages and the number of weevils in a fumigation-repellency chamber. Number of weevils that moved from the bioassay chamber was recorded one hour after weevil introduction. Leaves of R. graveolens were extracted in hexane, ethyl acetate, methanol, distilled water and different concentrations 10, 50, 100% (v/v) were assessed separately to evaluate repellent activity by means of an area preference bioassay. In all experiments, ten weevils for each were tested and the number repelled was recorded 30 minutes after weevil introduction. Highest contact and fumigant repellent effects were elicited by 7.0 g of leaf powder resulting 96% and 95% respectively, whilst lowest dose also produced more than 50% repellency indicating extremely strong repellent action of the plant powder. In comparison, aqueous extract exhibited the most potent repellent activity (91%) while other extracts were producing over 70% repellent effects on weevils at the concentration of 100% (v/v). Overall findings of the study suggest that both powder and extracts of R. graveolens leaves could be used as eco-friendly agents for post-harvest rice protection. KEYWORDS: Ruta graveolens, Sitophilus oryzae, stored rice, leaf powder, repellen

    Rapid bidirectional reorganization of cortical microcircuits.

    Get PDF
    Mature neocortex adapts to altered sensory input by changing neural activity in cortical circuits. The underlying cellular mechanisms remain unclear. We used blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to show reorganization in somatosensory cortex elicited by altered whisker sensory input. We found that there was rapid expansion followed by retraction of whisker cortical maps. The cellular basis for the reorganization in primary somatosensory cortex was investigated with paired electrophysiological recordings in the periphery of the expanded whisker representation. During map expansion, the chance of finding a monosynaptic connection between pairs of pyramidal neurons increased 3-fold. Despite the rapid increase in local excitatory connectivity, the average strength and synaptic dynamics did not change, which suggests that new excitatory connections rapidly acquire the properties of established excitatory connections. During map retraction, entire excitatory connections between pyramidal neurons were lost. In contrast, connectivity between pyramidal neurons and fast spiking interneurons was unchanged. Hence, the changes in local excitatory connectivity did not occur in all circuits involving pyramidal neurons. Our data show that pyramidal neurons are recruited to and eliminated from local excitatory networks over days. These findings suggest that the local excitatory connectome is dynamic in mature neocortex

    Applications of Computation-In-Memory Architectures based on Memristive Devices

    Get PDF
    Today's computing architectures and device technologies are unable to meet the increasingly stringent demands on energy and performance posed by emerging applications. Therefore, alternative computing architectures are being explored that leverage novel post-CMOS device technologies. One of these is a Computation-in-Memory architecture based on memristive devices. This paper describes the concept of such an architecture and shows different applications that could significantly benefit from it. For each application, the algorithm, the architecture, the primitive operations, and the potential benefits are presented. The applications cover the domains of data analytics, signal processing, and machine learning
    • …
    corecore