92,873 research outputs found
John Leach
No full text"410603 F/O John Leach (Bluey) No 2 Squadron Hughes Field Sept 1944 - July 1945 T.P.I. Badge 11587".410603 Flying Officer John Leach (Bluey). Number 2 Squadron, Hughes Field. September 1944 - July 1945 Totally and Permanently Incapacitated Veterans Association Badge 11587
A simplified model for Anglo Platinum's continuous secondary leach in the base metals' refinery
No full textIncludes bibliographical references (leaves 80-82).An Excel-based mathematical model simulating the Base Metal's Refinery Secondary Leach operation is developed in this thesis. Fundamental building blocks of batch leach data, equipment specifications, process conditions and feed characteristics are used to develop the model. The aim of which is to develop a tool to verify actual plant performance against theoretical performance and assist with troubleshooting in the plant or serve as a basis for future autoclave design. In the present study the model is specifically used to investigate the cause of the reduced leach efficiencies that the plant is experiencing
Leach, F H, WX10052
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/398721Surname: LEACH. Given Name(s) or Initials: F H. Military Service Number or Last Known Location: WX10052. Missing, Wounded and Prisoner of War Enquiry Card Index Number: 40571.215990
Item: [2016.0049.31014] "Leach, F H, WX10052
Leach, A F, VX13568
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/398718Surname: LEACH. Given Name(s) or Initials: A F. Military Service Number or Last Known Location: VX13568. Missing, Wounded and Prisoner of War Enquiry Card Index Number: 8569.215987
Item: [2016.0049.31011] "Leach, A F, VX13568
Microfluidic solvent extraction of platinum and palladium from a chloride leach solution using Alamine 336
No full textMicrofluidic solvent extraction (μSX) of platinum and palladium from chloride leach solution using Alamine 336 had been conducted. The leach solution was produced by leaching of spent automotive catalysts. A microfluidic Y–Y channel embedded in a Pyrex™ microchip was used as the extraction system. Platinum and palladium extractions (>99%) occurred at μSX contact time as fast as 1 s with subsequent marginal extraction efficiency increases for longer contact times with comparable extraction performance to that of bulk SX. Findings from this preliminary study are useful in initiating a new metallurgical technique in the field of recovering precious (high-value) metals present in low concentrations which are otherwise not technically amenable (or economically viable) to extraction using current conventional methods
[Portrait of Petty Officer James F. Leach]
No full textPortrait of Petty Officer James F. Leach, visible from the neck up, wearing his uniform. The text on the bottom of the picture contains information about his rank, and a description of how he was killed and where: "P/O James F. Leach born March 30th, 1914 Co. Pilot C 47 Died in airplane crash on Isle of Corsica Jan. 23rd, 1945, Flying from Algiers to his home base in Florence, Italy.
Research routing and MAC based on LEACH and S-MAC for energy efficiency and QoS in wireless sensor network
No full textThe wireless sensor is a micro-embedded device with weak data processing capability and small storage space. These nodes need to complete complex jobs, including data monitoring, acquisition and conversion, and data processing. Energy efficiency should be considered as one of the important aspects of the Wireless Sensor Network (WSN) throughout architecture and protocol design. At the same time, supporting Quality of Service (QoS) in WSNs is a research field, because the time-sensitive and important information is expected for the transmitting to to the sink node immediately. The thesis is supported by the projects entitled “The information and control system for preventing forest fires”, and “The Erhai information management system”, funded by the Chinese Government. Energy consumption and QoS are two main objectives of the projects. The thesis discusses the two aspects in route and Media Access Control (MAC).
For energy efficiency, the research is based on Low Energy Adaptive Clustering Hierarchy (LEACH) protocol. LEACH is a benchmark clustering routing protocol which imposes upon cluster heads to complete a lot of aggregation and relay of messages to the base-station. However, there are limitations in LEACH. LEACH does not suit a wide area in clustering strategy and multi-hop routing. Moreover, routing protocols only focus on one factor, combining the clustering strategy and multi-hop routing mechanism were not considered in routing protocol for performance of network.
QoS is supported by the MAC and routing protocol. Sensor MAC(S-MAC) makes the use of the periodically monitoring / sleeping mechanism, as well as collision and crosstalk avoidance mechanism. The mechanism reduces energy costs. Meanwhile, it supports good scalability and avoids the collision. However, the protocols do not take the differentiated services. For supporting QoS,A new route protocol needs to be designed and realized on embed platforms, which has WIFI mode and a Linux operation system to apply on the actual system.
This research project was conducted as following the steps: A new protocol called RBLEACH is proposed to solve cluster on a widely scale based on LEACH. The area is divided into a few areas, where LEACH is improved to alter the selecting function in each area. RBLEACH creates routes selected by using a new algorithm to optimize the performance of the network. A new clustering method that has been developed to use several factors is PS-ACO-LEACH. The factors include the residual energy of the cluster head and Euclidean distances between cluster members and a cluster head. It can optimally solve fitness function and maintain a load balance in between the cluster head nodes, a cluster head and the base station. Based on the “Ant Colony” algorithm and transition of probability, a new routing protocol was created by “Pheromone” to find the optimal path of cluster heads to the base station. This protocol can reduce energy consumption of cluster heads and unbalanced energy consumption. Simulations prove that the improved protocol can enhance the performance of the network, including lifetime and energy conservation. Additionally, Multi Index Adaptive Routing Algorithm (MIA-QR) was designed based on network delay, packet loss rate and signal strength for QoS. The protocol is achieved by VC on an embedded Linux system. The MIA-QR is tested and verified by experiment and the protocol is to support QoS. Finally, an improved protocol (SMAC -SD) for wireless sensor networks is proposed, in order to solve the problem of S-MAC protocol that consider either service differentiation or ensure quality of service. According to service differentiation, SMAC-SD adopts an access mechanism based on different priorities including the adjustment of priority mechanisms of channel access probability, channel multi-request mechanisms and the configuring of waiting queues with different priorities and RTS backoff for different service, which makes the important service receive high channel access probability, ensuring the transmission quality of the important service. The simulation results show that the improved protocol is able to gain amount of important service and shortens the delay at the same time. Meanwhile, it improves the performance of the network effectivel
Quantitative Scalability of Nodes and Geographical Coverage in LEACH Protocol
No full textEnergy optimisation using clustering remains a constant challenge in wireless sensor networks (WSNs). The high volume of data generated within these networks leads to excessive energy consumption when transferring it to the processing center. Therefore, clustering protocols, in particularly hierarchical routing protocols dedicated to WSNs, must imperatively integrate energy efficiency mechanisms in order to extend the functional lifetime of the nodes and the network. In this paper, we focus on an in-depth analysis of scalability in the Low Energy Adaptive Clustering Hierarchy (LEACH) protocol. The LEACH protocol, renowned for its random and distributed approach to WSNs energy optimisation, forms the focus of our analysis and exploration. Our study focuses in particular on the quantitative scalability of nodes and the scalability of geographical coverage. The aim is to improve our understanding of the behaviour of the LEACH protocol in large-scale environments, particularly with regard to node and network lifetime and energy management parameters
Vortex knots in light
No full textOptical vortices generically arise when optical beams are combined. Recently, we reported how several laser beams containing optical vortices could be combined to form optical vortex loops, links and knots embedded in a light beam (Leach et al 2004 Nature 432 165). Here, we describe in detail the experiments in which vortex loops form these structures. The experimental construction follows a theoretical model originally proposed by Berry and Dennis, and the beams are synthesized using a programmable spatial light modulator and imaged using a CCD camera
Artibeus Leach 1821
No full textArtibeus Leach, 1821. Trans. Linn. Soc. London, 13:75. TYPE SPECIES: Artibeus jamaicensis Leach, 1821. SYNONYMS: Dermanura, Enchisthenes, Koopmania. COMMENTS: For synonyms see Jones and Carter (1979:8); but see also Hall (1981:163) and Owen (1991).Published as part of Karl F. Koopman, 1993, Order Chiroptera, pp. 137-241 in Mammal Species of the World (2 nd Edition), Washington and London :Smithsonian Institution Press on page 187, DOI: 10.5281/zenodo.735306
- …
