• Title/Summary/Keyword: term formation

Search Result 655, Processing Time 0.023 seconds

An Investigation on the Formation Characteristics of a Single Vortex Interacting with Counterflow Nonpremixed Flame (대향류 비예혼합화염과 상호작용하는 단일 와동의 생성특성에 관한 연구)

  • Yoo, Byung-Hun;Oh, Chang-Bo;Hwang, Chul-Hong;Lee, Chang-Eon
    • 한국연소학회:학술대회논문집
    • /
    • 2002.11a
    • /
    • pp.49-56
    • /
    • 2002
  • A two-dimensional direct numerical simulation is performed to investigate the formation characteristics of a single vortex interacting with $CH_4/N_2$-Air counterflow nonpremixed flame. The numerical method was based on a predictor-corrector scheme for a low Mach number flow. The detailed transport properties and a 16-step augmented reduced mechanism are adopted in this calculation. The budgets of the vorticity transport equation arc examined to reveal the mechanisms leading to the formation, evolution and dissipation of a single vortex interacting with counterflow nonpremixed flame. It is found that the stretching term, which depends on the azimuthal component of vorticity, and radial velocity, mainly generates vortieitv in non-reacting and reacting flows. The viscous and baroclinic torque term destroy the vorticity in non-reacting flow. In addition, the baroclinic torque term due to density and pressure gradient generates vorticity, while viscous and the volumetric expansion terms due to density gradient destroy vorticity in reacting flow.

  • PDF

Long-term Fistula Formation Due to Retained Bullet in Lumbar Spine after Gunshot Injury

  • Jeon, Se-Il;Im, Soo Bin;Jeong, Je Hoon;Cha, Jang Gyu
    • Journal of Trauma and Injury
    • /
    • v.30 no.2
    • /
    • pp.51-54
    • /
    • 2017
  • We here report a case of long-term fistula formation due to bullet retention for 30 years in the lumbar spine after a gunshot injury, and describe its treatment. A 62-year-old male visited our hospital due to pus-like discharge from his left flank. The discharge had been present for 30 years, since his recovery from an abdominal gunshot injury. A spine radiography showed radiopaque material in the body of the third lumbar vertebra. Foreign body was removed using an anterolateral retroperitoneal approach. The postoperative course was uneventful. The patient was discharged 7 days after the operation and was followed-up for 8 months, during which time, the fistula did not reoccur. A bullet retained long term in the vertebral body may cause obstinate osteomyelitis and fistula formation. A fistula caused by a foreign body in the spine can be effectively treated by surgical removal.

Micromechanics based Models for Pore-Sructure Formation and Hydration Heat in Early-Age Concrete (초기재령 콘크리트의 세공구조 형성 및 발영특성에 관한 미시역학적 모델)

  • 조호진;박상순;송하원;변근주
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1999.04a
    • /
    • pp.123-128
    • /
    • 1999
  • Recently, as a performance based design concept is introduced, assurance of expected performances on serviceability and safety in the whole span of life is exactly requested. So, quantitative assessments about durability related properties of concrete in early-age long term are come to necessary, Especially in early age, deterioration which affects long-term durability performance can be occurred by hydration heat and shrinkage, so development of reasonable hydration heat model which can simulate early age behavior is necessary. The micor-pore structure formation property also affects shrinkage behavior in early age and carbonations and chloride ion penetration characteristic in long term, So, for the quantitative assessment on durability performance of concrete, modelings of early age concrete based on hydration process and micor-pore structure formation characteristics are important. In this paper, a micromechanics based hydration heat evolution model is adopted and a quantitative model which can simulate micro-pore structure development is also verified with experimental results. The models can be used effectively to simulate the early-age behavior of concrete composed of different mix proportions.

  • PDF

Water Mass Formation Variability in the Intermediate Layer of the East Sea

  • Min, Hong-Sik;Kim, Cheol-Ho
    • Ocean Science Journal
    • /
    • v.41 no.4
    • /
    • pp.255-260
    • /
    • 2006
  • Long-term variability in the intermediate layer of the eastern Japan Basin has been investigated to understand the variability of water mass formation in the East Sea. The simultaneous decrease of temperature at shallower depths and oxygen increasing at deeper depths in the intermediate layer took place in the late 1960's sand the mid-1980's. Records of winter sea surface temperatures and air temperatures showed that there were cold winters that persisted for several years during those periods. Therefore, it was assumed that a large amount of newly-formed water was supplied to the intermediate layer during those cold winters. Close analysis suggests that the formation of the Upper Portion of Proper Water occurred in the late 1960's and the Central Water in the mid-1980's.

Essay on Terminology Formation and Translation Methodology in Korean (전문용어 조어 및 번역 방법론에 대한 시론)

  • LEE, Hyunjoo
    • Cross-Cultural Studies
    • /
    • v.31
    • /
    • pp.331-370
    • /
    • 2013
  • In this knowledge based society, the circulation of knowledge and information is more and more increasing. Terms, as denominations of every specialized concept, has grown in quantity and there are considerable amount of foreign terminology coming to settle down in Korean language. Since terminologies quickly generate and be extinguished, it is important to translate in appropriate way at the very first phase of terminology implementation. This article aims to elaborate the typology of korean terminology translation forms, and propose some guidelines for terminology formation and translation methodology. ISO terminology principle and other institutes' propositions for term formation as well as translational theories constitute two basic columns of the guidelines.

A Study on Long-Term Cycling Performance by External Pressure Change for Pouch-Type Lithium Metal Batteries

  • Seong-Ju Sim;Bong-Soo Jin;Jun-Ho Park;Hyun-Soo Kim
    • Journal of Electrochemical Science and Technology
    • /
    • v.15 no.2
    • /
    • pp.314-320
    • /
    • 2024
  • Lithium dendrite formation is one of the most significant problems with lithium metal batteries. The lithium dendrite reduces the lithium metal batteries' cycling life and safety. To apply consistent external pressure to a lithium metal pouch cell, we design a press jig in this study. External pressure creates dense lithium morphology by preventing lithium dendrite formation. After 300 cycles at 1 C, the cells with the external pressure perform far better than the cells without it, with a cycling retention of 97.8%. The formation of stable lithium metal is made possible by external pressure, which also enhances safety and cyclability.

International Joint Research for the Colloid Formation and Migration in Grimsel Test Site: Current Status and Perspectives

  • Sang-Ho Lee;Jin-Seok Kim;Bong-Ju Kim;Jae-Kwang Lee;Seung Yeop Lee;Jang-Soon Kwon
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.20 no.4
    • /
    • pp.455-468
    • /
    • 2022
  • Colloid Formation and Migration (CFM) project is being carried out within the Grimsel Test Site (GTS) Phase Ⅵ. Since 2008, the Korea Atomic Energy Research Institute (KAERI) has joined CFM to investigate the behavior of colloid-facilitated radionuclide transport in a generic Underground Research Laboratory (URL). The CFM project includes a long-term in-situ test (LIT) and an in-rock bentonite erosion test (i-BET) to assess the in-situ colloid-facilitated radionuclide transport through the bentonite erosion in the natural flow field. In the LIT experiment, radionuclide-containing compacted bentonite was equipped with a triple-packer system and then positioned at the borehole in the shear zone. It was observed that colloid transport was limited owing to the low swelling pressure and low hydraulic conductivity. Therefore, a postmortem analysis is being conducted to estimate the partial migration and diffusion of radionuclides. The i-BET experiment, that focuses more on bentonite erosion, was newly designed to assess colloid formation in another flow field. The i-BET experiment started with the placement of compacted bentonite rings in the double-packer system, and the hydraulic parameters and bentonite erosion have been monitored since December 2018.

Background to the Formation of the Term Hyangjang (香粧) and Change in Cosmetic (化粧) Culture -Focusing on Change from Visual Make-up to Olfactory Make-up- (향장(香粧) 용어의 성립배경과 화장(化粧)문화의 변화 -시각적 화장에서 후각적 화장으로의 변화를 중심으로-)

  • Baek, Ju Hyun;Chae, Keum Seok
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.41 no.2
    • /
    • pp.197-211
    • /
    • 2017
  • Modernization drastically changed the cosmetic culture of Korea and Japan. A classic case that shows this is the appearance of the term 'Hyangjang (香粧)'. This paper investigated the background to the formation of the term Hyangjang (香粧), and reviewed the aspects of cosmetic culture that changed with the emergence of Hyangjangpum (香粧品), or cosmetics containing perfume. The investigation revealed that the term Hyangjang (香粧) appeared for the first time in Hirano (1899), a literature published in the Meiji period in Japan, and that the new term Hyangjang (香粧) had been formed against the background of advanced Western synthetic perfume and played an important role in contemporary techniques for the manufacture of cosmetics. The term Hyangjang (香粧) and cosmetics containing perfume, or Hyangjangpum (香粧品) were then introduced from Japan to Korea. In Korea, the term 'Hyangjang (香粧)' appeared for the first time in an advertising copy written by Hyeon Hui-un, a pioneer of the Korean modern theater movement during the period of Japanese colonial rule. At that time, cosmetic companies in Korea and Japan were releasing cosmetic products that contained perfume that stimulated a women's desire to purchase them by emphasizing 'fragrance' in their advertising. Existing public tendencies to regard a fragrant smell from a made-up face as vulgar were changing and the public perception of fragrance were also changing. The appearance of Hyangjangpum (香粧品) indicates that the existing cosmetic culture revolving around visual sense changed into a complex cosmetic culture involving olfaction. This change in culture is significant in that it heralded the direction of future development towards cosmetic culture that uses increase combinations of different senses including touch, taste, and hearing.

Did Fluvial Terrace of Mountain Streams in Korea Form in Each Glacial Stage? (우리나라 산지 하천의 하안단구는 매 빙기마다 형성되었는가?)

  • Lee, Gwang-Ryul
    • Journal of The Geomorphological Association of Korea
    • /
    • v.26 no.3
    • /
    • pp.19-30
    • /
    • 2019
  • This study summarizes domestic and foreign previous works on fluvial terrace with absolute ages to discuss formative process of climatic terrace in Korea. Different from traditional climatic terrace model, approximately three quarters from foreign works have argued that formation of climatic terrace can be attributed to medium- and short-term climatic change or other environmental factors, rather than long-term climatic change of glacial and interglacial cycles. Based on previous works on fluvial terrace in Korea, it can be suggested that fluvial terrace in Korea formed not due to long-term climatic change of 100,000-year cycles related to glacial and interglacial cycles, but due to medium- and short-term climatic change or climatic event of tens of thousands of years related to intensity change in summer monsoon, one of the important factors affecting precipitation in Korea.

UNSTEADY THREE-DIMENSIONAL ANALYSIS OF TRANSVERSE FUEL INJECTION INTO A SUPERSONIC CROSSFLOW USING DETACHED EDDY SIMULATION (DES를 이용한 초음속 유동내 수직 연료분사 유동의 비정상 3차원 해석)

  • Won, S.H.;Moon, S.Y.;Jeung, I.S;Choi, J.Y.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2008.03a
    • /
    • pp.97-103
    • /
    • 2008
  • Unsteady three-dimensional flowfields generated by transverse fuel injection into a supersonic mainstream are simulated with a DES turbulence model. Comparisons are made with experimental results in term of the temporal eddy position and eddy formation frequency. The vorticity field around the jet exit is also analyzed to understand the formation mechanism of the jet vortical structures. Results indicate that the DES model correctly predicts the convection characteristics of the large scale eddies. However, it is also observed that the numerical results slightly overpredict the eddy formation frequency. The jet vortical structures are developed from the competing vortices in the recirculation region of upstream boundary.

  • PDF