• Title/Summary/Keyword: Western Australia

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Seismic vulnerbility analysis of Bankstown's West Terrace railway bridge

  • Mirza, Olivia;Kaewunruen, Sakdirat;Galia, Darren
    • Structural Engineering and Mechanics
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    • v.57 no.3
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    • pp.569-585
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    • 2016
  • This paper highlights a case study that investigates the behaviour of existing bridge, West Terrace Bridge, induced by horizontal seismic loading. Unfortunately the lack of past information related to seismic activity within the NSW region has made it difficult to understand better the capacity of the structure if Earthquake occurs. The research was conducted through the University of Western Sydney in conjunction with Railcorp Australia, as part of disaster reduction preparedness program. The focus of seismic analyses was on the assessment of stress behaviour, induced by cyclic horizontal/vertical displacements, within the concrete slab and steel truss of the bridge under various Earthquake Year Return Intervals (YRI) of 1-100, 1-200, 1-250, 1-500, 1-800, 1-1000, 1-1500, 1-2000 and 1-2500. Furthermore the stresses and displacements were rigorously analysed through a parametric study conducted using different boundary conditions. The numerical analysis of the concrete slab and steel truss were performed through the finite element software, ABAQUS. The field measurements and observation had been used to validate the results drawn from the finite element simulation. It was illustrated that under a YRI of 1/1000 the bottom chord of the steel truss failed as the stress induced surpassed the ultimate stress capacity and the horizontal displacement exceeded the allowable displacement measured in the field observations whereas the vertical displacement remained within the previously observed limitations. Furthermore the parametric studies in this paper demonstrate that a change in boundary conditions alleviated the stress distribution throughout the structure allowing it to withstand a greater load induced by the earthquake YRI but ultimately failed when the maximum earthquake loading was applied. Therefore it was recommended to provide a gap of 50mm on the end of the concrete slab to allow the structure to displace without increasing the stress in the structure. Finally, this study has proposed a design chart to showcase the failure mode of the bridge when subjected to seismic loading.

A Case Study of Prediction and Analysis of Unplanned Dilution in an Underground Stoping Mine using Artificial Neural Network (인공신경망을 이용한 지하채광 확정선외 혼입 예측과 분석 사례연구)

  • Jang, Hyongdoo;Yang, Hyung-Sik
    • Tunnel and Underground Space
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    • v.24 no.4
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    • pp.282-288
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    • 2014
  • Stoping method has been acknowledged as one of the typical metalliferous underground mining methods. Notwithstanding with the popularity of the method, the majority of stoping mines are suffering from excessive unplanned dilution which often becomes as the main cause of mine closure. Thus a reliable unplanned dilution management system is imperatively needed. In this study, reliable unplanned dilution prediction system is introduced by adopting artificial neural network (ANN) based on data investigated from one underground stoping mine in Western Australia. In addition, contributions of input parameters were analysed by connection weight algorithm (CWA). To validate the reliability of the proposed ANN, correlation coefficient (R) was calculated in the training and test stage which shown relatively high correlation of 0.9641 in training and 0.7933 in test stage. As results of CWA application, BHL (Length of blast hole) and SFJ (Safety factor of Joint orientation) show comparatively high contribution of 18.78% and 19.77% which imply that these are somewhat critical influential parameter of unplanned dilution.

Investigating Library Cooperative Systems for Acquisition of Multi-cultural Materials (협력기반의 다문화자료 입수 체계에 관한 연구)

  • Cho, Yong-Wan
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.22 no.4
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    • pp.45-70
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    • 2011
  • Today's S. Korean society has become more multicultural, so many libraries in S. Korea have been working hard to serve their "new customers". In this regard, this study intends to investigate library cooperative systems for acquisition of multicutural materials in Western countries to relieve difficulties of libraries in S. Korea in acquiring multicutural materials. the study analyzed 23 national libraries, state libraries, public libraries and library systems in North America, Australia and Northern European Countries. The research found categorization schemes. First, library cooperative systems are divided into two groups according to cooperative methods: cooperative acquisition and bulk loan method. Second, the systems are categorized according to the territorial scope of the service: country, state or province, borough or city and inter-library. The study also analyzed and synthesized the characteristics of these systems. It finally provides recommendations to apply the methods used by the library cooperative systems in Western countries to Korean's situation.

An In-depth Analysis of the Result of the International Comparative Study of Mathematics (학업 성취도 국제 비교 연구에 나타난 우리나라 학생들의 수학 성취도 심층 분석)

  • Park Kyung Mee
    • Journal of Educational Research in Mathematics
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    • v.14 no.4
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    • pp.387-401
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    • 2004
  • The recent international comparative studies such as PISA(Program for International Student Assessment) and TIMSS-R(Third International Mathematics and Science Study-Repeat) provide results of relative mathematics achievement of participating countries. The purpose of this paper is to compare the mathematics results of PISA and TIMSS-R. To make PISA and TIMSS-R results comparable, they were standardized. The close investigation of these standardized results reveals that the two Asian countries(Korea and Japan) and several English speaking countries have the commonality in mathematics achievement. Thus this study looks for patterns and similarities within a group of Asian countries(Korea and Japan) and Western countries(the U.S and Australia) by in-depth analysis of PISA mathematics achievement based on item response theory. As a result, it was noted that Western countries tend to perform well on open constructed items and are likely to perform better when an item involves less formal mathematics. On the other hand, Asian countries perform well when an item involves numeric or algebraic computation related to curriculum-based content, but they are relative poor at an item calls for verbal explanations or interpretations of graphs.

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Interdecadal Change of Summer Rainfall in the Region of Korea and Northern China (한국-중국 북부지역에서 여름 강수량의 십년간 변동)

  • Choi, Jae-Won;Cha, Yumi;Kim, Jeoung-Yun;Lu, Riyu
    • Journal of the Korean earth science society
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    • v.38 no.1
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    • pp.35-48
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    • 2017
  • This study analyzed the obvious increasing tendency of summer (June to August) rainfall in the region of Korea- and northern China ($35^{\circ}-40^{\circ}N$, $110^{\circ}-130^{\circ}E$) in the late 1990s. In order to investigate the causes of the increase in summer rainfall since 1998, we analyzed the difference of the rainfall average between 1998-2012 and 1981-1997. The analysis of the 850 hPa stream flows showed that the huge anomalous anticyclonic circulations were developed in North Pacific and eastern Australia. In both hemispheres, the anomalous easterlies (anomalous trade winds) were strengthened from the equatorial central Pacific to the tropical western Pacific by the anomalous circulations, which was an anomalous circulation pattern shown in La $Ni{\tilde{n}}a$ years. As for the 200 hPa stream flows, the huge anomalous cyclonic circulations were also developed in both South Pacific and North Pacific. These two anomalous circulations reinforced the anomalous westerlies in the equatorial central and western Pacific, leading to the increase in summer rainfall in the region of Korea- and northern China since the late 1990s in association with La $Ni{\tilde{n}}a$ pattern, which was resulted in strengthening the Walker circulation. Recently in East Asia, the local Hadley circulation has been strengthened in which upward flows in the equatorial western Pacific and mid-latitude region of East Asia have descended in the subtropical western Pacific.

Case studies of shallow marine investigations in Australia with advanced underwater seismic refraction (USR) (최신 수중 탄성파 굴절법(USR)을 이용한 호주의 천부해양탐사 사례연구)

  • Whiteley, Robert J.;Stewart, Simon B.
    • Geophysics and Geophysical Exploration
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    • v.11 no.1
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    • pp.34-40
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    • 2008
  • Underwater seismic refraction with advanced interpretation approaches makes important contributions to shallow marine exploration and geotechnical investigations in Australia's coastal areas. A series of case studies are presented to demonstrate the recent applications of continuous and static USR methods to river crossing and port infrastructure projects at various sites around Australia. In Sydney, static underwater seismic refraction (USR) with bottom-placed receivers and borehole seismic imaging assisted the development of improved geotechnical models that reduced construction risk for a tunnel crossing of the Lane Cove River. In Melbourne, combining conventional boomer reflection and continuous USR with near-bottom sources and receivers improved the definition of a buried, variably weathered basalt flow and assisted dredging assessment for navigation channel upgrades at Geelong Ports. Sand quality assessment with continuous USR and widely spaced borehole information assisted commercial decisions on available sand resources for the reclamation phase of development at the Port of Brisbane. Buried reefs and indurated layers occur in Australian coastal sediments with the characteristics of laterally limited, high velocity, cap layers within lower velocity materials. If these features are not recognised then significant error in depth determination to deeper refractors can occur. Application of advanced refraction inversion using wavefront eikonal tomography to continuous USR data obtained along the route of a proposed offshore pipeline near Fremantle allowed these layers and the underlying bedrock refractor to be accurately imaged. Static USR and the same interpretation approach was used to image the drowned granitic regolith beneath sediments and indurated layers in the northern area of Western Australia at a proposed new berthing site where deep piling was required. This allowed preferred piling sites to be identified, reducing overall pile lengths. USR can be expected to find increased application to shallow marine exploration and geotechnical investigations in Australia's coastal areas as economic growth continues and improved interpretation methods are developed.

Agricultural Systems for Saline Soil: The Potential Role of Livestock

  • Masters, D.G.;Norman, H.C.;Barrett-Lennard, E.G.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.2
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    • pp.296-300
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    • 2005
  • Human-induced soil salinity is becoming a major threat to agriculture across the world. This salinisation occurs in both irrigated and rain-fed agricultural zones with the highest proportions in the arid and semi-arid environments. Livestock can play an important role in the management and rehabilitation of this land. There are a range of plants that grow in saline soils and these have been used as animal feed. In many situations, animal production has been poor as a result of low edible biomass production, low nutritive value, depressed appetite, or a reduction in efficiency of energy use. Feeding systems are proposed that maximise the feeding value of plants growing on saline land and integrate their use with other feed resources available within mixed livestock and crop farming systems. Salt-tolerant pastures, particularly the chenopod shrubs, have moderate digestible energy and high crude protein. For this reason they represent a good supplement for poor quality pastures and crop residues. The use of salt-tolerant pasture systems not only provides feed for livestock but also may act as a bio-drain to lower saline water tables and improve the soil for growth of alternative less salt tolerant plants. In the longer term there are opportunities to identify and select more appropriate plants and animals for saline agriculture.

Damage Assessment of Free-fall Dropped Object on Sub-seabed in Offshore Operation

  • Won, Jonghwa;Kim, Youngho;Park, Jong-Sik;Kang, Hyo-dong;Joo, YoungSeok;Ryu, Mincheol
    • Journal of Advanced Research in Ocean Engineering
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    • v.1 no.4
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    • pp.198-210
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    • 2015
  • This paper presents the damage assessment of a free-fall dropped object on the seabed. The damage to a dropped object totally depends on the relationship between the impact energy and the soil strength at the mudline. In this study, unexpected dropping scenarios were first assumed by varying the relevant range of the impact velocity, structure geometry at the moment of impact, and soil strength profile along the penetration depth. Theoretical damage assessments were then undertaken for a free-fall dropping event with a fixed final embedment depth for the structure. This paper also describes the results of a three-dimensional large deformation finite element analysis undertaken for the purpose of validation. The analyses were carried out using the coupled Eulerian-Lagrangian approach, modifying the simple elastic-perfectly plastic Tresca soil model. The validation exercises for each dropping scenario showed good agreement, and the present numerical approach was capable of predicting the behavior of a free-fall dropped object.

ISM Properties and Star Formation Activities in IC 10 : 2D Cross Correlation Analysis of Multi-wavelength data

  • Kim, Seongjoong;Lee, Bumhyun;Oh, Se-Heon;Chung, Aeree;Rey, Soo-Chang;Jung, Teahyun;Kang, Miju
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.2
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    • pp.31.3-32
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    • 2015
  • We present the physical properties of star forming regions in IC 10 obtained from Korea VLBI Network (KVN) 22GHz, the Submillimeter Array (SMA) CO, Very Large Array (VLA) HI 21cm, optical (U, B, V and H-alpha), and Spitzer infrared observations. IC 10 is a nearby (~0.7Mpc) irregular blue compact dwarf (BCD) galaxy which is likely to be experiencing an intense and recent burst of star formation. This nearby infant system showing high star formation rate but low metallicity (<20% of that of the Sun) provides critical environment of interstellar medium (ISM) under which current galactic star formation models are challenged. To make quantitative analysis of the ISM in the galaxy, we apply 2D cross-correlation technique to the multi-wavelength data for the first time. By cross-correlating different tracers of star formation, dust and gas phases in IC 10 in a two dimensional way, we discuss the gas properties and star formation history of the galaxy.

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Narrative review: the evidence for neurotoxicity of dental local anesthetics

  • Aps, Johan;Badr, Nelly
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.20 no.2
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    • pp.63-72
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    • 2020
  • Dental local anesthesia is performed daily on a global scale. Adverse effects are rare, but the topic of neurotoxicity of local anesthetics deserves to be explored, as publications can be controversial and confusing. Therefore, a need was felt to address and question the evidence for potential neurotoxicity of dental local anesthetics. This review aimed to assess the studies published on the neurotoxicity of dental local anesthetics. A Pubmed search was conducted between January 2019 and August 2019. This revealed 2802 hits on the topic of neurotoxicity or cytotoxicity of the following anesthetics: lidocaine, prilocaine, mepivacaine, articaine, ropivacaine, and bupivacaine. Only 23 papers were deemed eligible for this review: 17 in vitro studies, 3 reviews and 3 audits of national inquiries. The heterogeneous literature on this topic showed that all dental local anesthetics are potentially neurotoxic in a concentration and/or exposure time fashion. There seems no consensus about what cell lines are to be used to investigate the neurotoxicity of local anesthetics, which makes the comparison between studies difficult and ambiguous. However, the bottom line is that all dental local anesthetics have a neurotoxic potential, but that there is no unanimity in the publications about which local anesthetic is the least or the most neurotoxic.