• Title/Summary/Keyword: Spatial Properties

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Disposal Characteristics of Dredged Material from the Hopper Dredger (호퍼준설선의 투기특성)

  • Jeong, D.D.;Lee, J.W.
    • Journal of Korean Port Research
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    • v.11 no.2
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    • pp.203-214
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    • 1997
  • Hydraulic dredgers(Hopper dredger) are the most important piece of equipment in the entire harbor engineering field, and most suitable for the removal of sand and weakly consloidated sediment such as silt. In maintenance dredging, specially confined harbor or congested passage area, Hopper dredger is user most popularly because less obstruction and danger to navigation than other mostly stationary dredgers. Investigation of the physical behave of dredged material disposal in coastal water from the Hopper dredger includes estimations of pattern as well as thickness of material on the bottom. Calculation based on vertical settling and horizontal advection of single particles ignore the effects of bulk properties of the disposed marterial, vertical and horizontal diffusion. and material dilution due to the entrainment of ambient water during descent. This paper focuses on the analysis of dredging and dumping characteristics and the spatial and temporal changes in the dumping fields for the water column and bottom at a hypothetically confined coastal water. This model accounts the behavior of material after release from the hopper dredger. It is shown that the model describes the qualitative feature of prototype dumping process and its response.

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Understanding high-mass star formation through KaVA observations of water and methanol masers

  • Kim, Kee-Tae;Hirota, Tomoya
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.51.4-51.4
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    • 2019
  • We started a systematic observational study of the 22 GHz water and 44 GHz class I methanol masers in 87 high-mass young stellar objects (HM-YSOs) as a KaVA large program (LP). The primary goal is to understand dynamical evolution of HM-YSOs and their circumstellar structures by measuring spatial distributions and 3-dimensional velocity fields of multiple maser species. In the first-year observations (2016-2017), we made snap-shot imaging surveys of 25 water and 19 methanol maser sources. In the second-year observations (2018-2019), we have carried out monitoring observations of 19 water and 3 methanol maser sources that were selected on the basis of the first-year survey results. By combining follow-up observations with VERA (distances), JVN/EAVN (6.7 GHz methanol masers), and ALMA cycles 3 and 6 (thermal lines/continuum), we will provide novel information on physical properties (density, temperature, size, mass), 3D dynamical structures of disk/jet/outflow/infalling envelope, and relationship between evolutionary of HM-YSOs. In this presentation, we will report the current status and future plans of our KaVA large program.

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Narrow-band Ca Photometry for Dwarf Spheroidal Galaxies: Recent Results and Future Work

  • Kim, Hak-Sub;Han, Sang-Il;Yoon, Suk-Jin
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.75.2-75.2
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    • 2019
  • This poster introduces the ongoing "Narrow-band Ca Photometry for Dwarf Spheroidal Galaxies" project and presents the latest results. The project aims to explain the formation and evolution of dwarf spheroidal galaxies by examining the structural properties of stellar populations as a function of metallicity. To overcome the lack of stars with known spectroscopic metallicities for dwarf spheroidal galaxies, we apply the hk index as a photometric metallicity indicator to three galaxies-Draco, Sextans, and Canes Venatici I. For all three galaxies, we found that metal-poor and metal-rich groups of red-giant-branch stars have distinct spatial distributions, in which metal-rich stars are centrally concentrated while metal-poor stars are relatively dispersed. In Sextans, we found an off-centered peak of metal-poor stars which is presumed to be a disrupting star cluster in this galaxy. We will discuss the implications of our results for the dwarf galaxy formation and possible directions on future work of this project.

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SED modelling of broadband emission in the pulsar wind nebula 3C 58

  • Kim, Seungjong;An, Hongjun
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.55.1-55.1
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    • 2019
  • We investigate broadband emission properties of the pulsar wind nebula (PWN) 3C 58 using a spectral energy distribution (SED) model. We attempt to match simultaneously the broadband SED and spatial variations and emission about 3C 58 in X-ray band. We further the model to explain a possible far-IR feature of which a hint is recently suggested in 3C 58: a small bump at ~10^11 GHz in the PLANCK and Herschel band. While external dust emission may easily explain the observed bump, it may be internal emission of PWNe implying an another additional population of particles. Although significance for the bump in 3C 58 is not higher than other PWNe, here we explore possible origins of the IR bump using the emission model and find that a population of electrons with GeV energies can explain the bump. If it is produced in the PWN, it may provide new insights into particle acceleration and flows in PWNe.

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Deep polarization observations of a ram pressure stripped galaxy, NGC 4522

  • Choi, Woorak;Chung, Aeree;Kim, Chang-goo;Lee, Bumhyun
    • The Bulletin of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.65.1-65.1
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    • 2020
  • We present high-resolution, high-sensitivity continuum data of NGC 4522 observed at 3 cm (X-band) and 10 cm (S-band) in full polarization mode using the JVLA. This observation has 2 - 4 times better spatial resolution and 2 - 5 times better sensitivity compared to previous continuum observations. NGC 4522 is a Virgo spiral galaxy undergoing active ram pressure stripping. This galaxy is particularly well known for the CO emission detected outside its stellar disk, some of which coincides with the extraplanar HI gas and Halpha patches. The major goal of our JVLA observation is to leverage our understanding of the influence of the ram pressure on the general ISM field and multi-phase medium. By combining our new deep radio continuum data and previous observations, we will investigate how the B-field properties can be affected by the ram pressure, and what roles the B-field plays in the stripping process of the multi-phased ISM and in the star formation activity when the ram pressure is present.

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USER-DEFINED PROPERTY SETS-BASED IFC EXTENSION FOR BRIDGE APPLICATION INFORMATION MODEL

  • Sang-Ho Lee;Sang Il Park;Munsu Yang
    • International conference on construction engineering and project management
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    • 2013.01a
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    • pp.433-436
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    • 2013
  • This study suggests IFC-based bridge information modeling methods and its application model in BIM environment. Data model extension for bridge structure was achieved using user-defined property sets based on IFC framework. First, identification information was added. Bridge members are identified through physical and spatial semantic information added as property sets. Instances for semantic information were assigned according to standardized rules. Second, CO2 related factors were added for application information model. It can play a role to calculate and manage the quantity of CO2 emission. Third, properties for temporary structure to estimate and manage the construction cost were added. Finally, we investigated proposed methods through implementing the application information model of bridges.

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Role of contrast-enhanced harmonic endoscopic ultrasonography (EUS) and EUS elastography in pancreatic lesions

  • Yasunobu Yamashita;Masayuki Kitano
    • Clinical Endoscopy
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    • v.57 no.2
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    • pp.164-174
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    • 2024
  • Pancreatic cancers have a poor prognosis, and their incident rates have risen. Endoscopic ultrasonography (EUS) is an efficient and reliable diagnostic modality for pancreatic lesions, providing high spatial resolution. However, while EUS helps to detect minor pancreatic lesions, nearly all solid pancreatic lesions are hypoechoic, which creates difficulty in making differential diagnoses of pancreatic lesions. When diagnosing pancreatic lesions, the performance of image-enhanced EUS techniques is essential, such as EUS elastography or contrast-enhanced harmonic EUS (CH-EUS). CH-EUS diagnosis is based on assessing the vascularity of lesions, whereas tissue elasticity is measured via EUS elastography. Elastography is either strain or shear-wave, depending on the different mechanical properties being evaluated. The usefulness of enhanced EUS techniques is demonstrated in this review for the differential diagnosis of pancreatic lesions, including solid and cystic lesions, and pancreatic cancer staging.

Nano-characterizations of low-dimensional nanostructural materials

  • Hye-Won Seo;Jae-Ung Lee;Chan-Ho Yang;Kanghyun Chu
    • Journal of the Korean Physical Society
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    • v.80
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    • pp.1035-1041
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    • 2022
  • Nondestructive nano-characterization methods were reviewed with respect to technical aspect and practicability. Micro-photoluminescence, cathodoluminscence and Raman spectroscopy with mapping modes were investigated as optical characterization tools, while electron backscatter diffraction and piezoresponse force microscopy were introduced as monitoring techniques for the crystallographic and electromechanical properties. Especially, the spatial resolution of the data acquisition and analysis was carefully inspected in the representative semiconducting nanomaterial systems. Some of efforts to overcome the limit of these characterizations were also taken into consideration.

Understanding the Structure-Property Relationship in Functional Materials Using 3D Atom Probe Tomography (3차원 원자단층현미경을 활용한 기능성 재료의 구조-특성 관계 해석)

  • Chanwon Jung
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.37 no.5
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    • pp.476-485
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    • 2024
  • Understanding the structure-property relationship in functional materials is crucial as microstructural features such as nano-precipitates, phase boundary, grain boundary segregation, and grain boundary phases play a key role in their functional properties. Atom probe tomography (APT) is an advanced analytical technique that allows for the three-dimensional (3D) mapping of atomic distributions and the precise determination of local chemical compositions in materials. Moreover, it offers sub-nanometer spatial resolution and chemical sensitivity at the tens of parts per million (ppm) level. Owing to its unique capabilities, this technique has been employed to uncover the 3D elemental distributions in a wide range of materials, including alloys, semiconductors, nanomaterials, and even biomaterials. In this paper, various kinds of examples are introduced for elucidating structure-property relationships on functional materials by utilizing the atom probe tomography.

A Study on the Change of Paradigm and Analysis of Qualitative Space in Public Space - Focused on the Entrance Floor in General Hospital over 500 beds in Korea - (공용 공간의 패러다임 변화와 질적 공간 분석 - 500병상 이상 국내 종합병원 진입층을 중심으로 -)

  • Son, Ji-Hye;Yang, Nae-Won
    • Korean Institute of Interior Design Journal
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    • v.23 no.6
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    • pp.212-220
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    • 2014
  • Entrance floor in hospital has became important space for medical service in holistic perspective and image enhancement. However, basically a discussion of the qualitative properties and the role of public space is paucity in change of public spaces paradigm. In accordance with this problem, this study consider the change of paradigm in public space based on earlier studies and create classification criterion of space. According to the criterion, G/D ratio and the qualitative spatial area ratio of 26 general hospitals which were planned over 500 beds are analyzed by case study method. The conclusion of this study is as follows. 1) The space according to the medical function is variable element. So the public space should be planned from function-subordinate space to self-reliance space in the future. 2) There is no correlation between the high G/D ratio and the high ratio of qualitative spacial area. In other word It's hard to say that the public space which G/D ratio is high is qualitative space. 3) Since 2000, various types in accordance with the circulation system is applied to public space. And ratio of qualitative spacial area is relatively high in the street type and the concourse type. 4) The qualitative spatial area ratio of stay space is higher than passage's one.