• Title/Summary/Keyword: Mechanism of spread

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The Weldability of Laminated Stator Core for Motor by Pulsed Nd:YAG Laser [II] - Investigation of Mechanism on Formation of Weld Defect - (펄스 Nd:YAG 레이저를 이용한 모터용 스테이터 적층코어의 용접특성 [II] - 용접결함의 형성 메커니즘 규명 -)

  • Kim Jong-Do;Kil Byung-Lea;Lee Chang-Je
    • Journal of Advanced Marine Engineering and Technology
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    • v.30 no.5
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    • pp.636-644
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    • 2006
  • Recently, there were some successful examples that the laser welding was introduced into production line. However, the spread of laser welding is not sufficient in many industries. There are several reasons why it is difficult to penetrate the laser welding into production lines. Because it is different from reflection, absorption and permeation of laser beam according to material and surface condition. Moreover, there are significant problems in processing such as absorption and scattering of beam by the induced plasma or plume. Therefore, understanding of mechanism on formation of weld defect in laser welding of the laminated core for motor is very important. In this paper, it was analyzed in terms of materials which was source of defect in laser welding and conventional arc welding. As a results of analysis, insulation coating film of the laminated core was judged to main factor of weld defect. it could be well aware as tracing carbon volume, and it was deduced that weld defect by insulation coating film was caused by difference of mechanism between the two heat sources.

The Characteristics of Various Stress in Cohesionless Soil with the Rammed Aggregate Pier (짧은 쇄석다짐말뚝(RAP)이 설치된 사질토지반의 응력변화 특성)

  • Chun, Byung-Sik;Kim, Kyung-Min;Kim, Jun-Ho
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.1108-1117
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    • 2005
  • RAP(rammed aggregate pier) method which is intermediate foundation of deep and shallow foundation is used to improve the ground with high compaction energy. This method is widely spread around the world, but there are few examples and systemic researches for failure mechanism and bearing capacity of this method are not organized yet. In this paper, soil laboratory tests were carried out to evaluate the applicability of RAP method as the foundation of a structure. And the bearing capacity and the failure mechanism of RAP method were studied with respect to various relative densities(35%, 65%, 90%), diameters(45mm, 60mm) and lengths(20cm, 30cm, 40cm). As results, stress concentration ratio decreased as diameter of RAP was increasing or length of RAP was decreased or relative density was decreased. however these results were not always constant. because systematic interaction between relative density and diameter and length of RAP can affect stress concentration ratio, more studies on stress concentration ratio are needed throughout laboratory and field tests.

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Rapid Management Mechanism Against Harmful Materials of Agri-Food Based on Big Data Analysis (빅 데이터 분석 기반 농 식품 위해인자 신속관리 방법)

  • Park, Hyeon;Kang, Sung-soo;Jeong, Hoon;Kim, Se-Han
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.6
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    • pp.1166-1174
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    • 2015
  • There were the attempts to prevent the spread of harmful materials of the agri-food through the record tracking of the products with the bar code, the partial information tracking of the agri-food storage and the delivery vehicle, or the control of the temperature by intuition. However, there were many problems in the attempts because of the insufficient information, the information distortion and the independent information network of each distribution company. As a result, it is difficult to prevent the spread over the life-cycle of the agri-food using the attempts. To solve the problems, we propose the mechanism mainly to do context awareness, predict, and track the harmful materials of agri-food using big data processing.

An Attack Behavior Expressions for Web Attack Analysis and Composing Attack Database (웹 공격 분석 및 공격 데이터베이스 생성을 위한 효과적인 표현 방법에 관한 연구)

  • Lee, Chang-Hoon
    • Journal of Advanced Navigation Technology
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    • v.14 no.5
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    • pp.725-736
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    • 2010
  • Nowadays, followed the internet service contents increasing makes also increase attack case on the web system. Usually web attack use mixed many kinds of attack mechanism for successfully attack to the server system. These increasing of the kinds attack mechanism, however web attack defence mechanism is not follow the spread of the attack. Therefore, for the defends web application, web attack should be categorizing and analysing for the effective defense. In this paper, we analyze web attack specification evidence and behavior system that use for effective expressions what we proposed. Also, we generate web attack scenario, it is for using verification of our proposed expressions.

Extraneural Metastasis of Glioblastoma Multiforme Presenting as an Unusual Neck Mass

  • Seo, Young-Jun;Cho, Won-Ho;Kang, Dong-Wan;Cha, Seung-Heon
    • Journal of Korean Neurosurgical Society
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    • v.51 no.3
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    • pp.147-150
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    • 2012
  • Glioblastoma multiforme(GBM) is the most aggressive intracranial tumor and it commonly spreads by direct extension and infiltration into the adjacent brain tissue and along the white matter tract. The metastatic spread of GBM outside of the central nervous system (CNS) is rare. The possible mechanisms of extraneural metastasis of the GBM have been suggested. They include the lymphatic spread, the venous invasion and the direct invasion through dura and bone. We experienced a 46-year-old man who had extraneural metastasis of the G8M on his left neck. The patient was treated with surgery for 5 times, radiotherapy and chemotherapy. He had survived 6 years since first diagnosed. Although the exact mechanism of the extraneural metastasis is not well understood, this present case shows the possibility of extraneural metastasis of the G8M, especially in patients with long survival.

Studies of the $TiO_2-Si$ Interface Bombarded by $Ar^+$ Ion Beam

  • Zhang, J.;Huang, N.K.;Lu, T.C.;Zeng, L.;Din, T.;Chen, Y.K.
    • Journal of the Korean Vacuum Society
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    • v.12 no.S1
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    • pp.63-66
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    • 2003
  • It is experimentally shown that a $TiO_2$ film on Si(111) substrate was prepared by using the technique of D.C. reaction sputter deposition with $Ar^{+}$ ion beam bombardment, and a layer-like structure was observed from the depth profile of the interface between $TiO_2$ film and Si substrate with Scanning Electron Microscopy and Electron Probe. It was also surprisingly discovered that Ti atoms could be detected at about 9 $\mu$m depth. The $TiO_2$-Si interface bombarded by $Ar^{+}$ ion beams revealed multi-layer structures, a mechanism might be caused by defect diffusion, impurity and matrix relocation. Multi-relocations of impurity and matrix atoms were as a result of profile broadening of the $TiO_2$-Si interface, and the spread due to matrix relocation in this system is shown to exceed much more the spread due to impurity relocation.

A Study on the Profitability of the Commercial Bank in Terms of Interest Rate Marketization : Based on FMOLS Model (FMOLS 모형을 이용한 상업은행 수익성에 대한 연구 : 금리 시장화의 시각에서)

  • He, Yugang
    • The Journal of Industrial Distribution & Business
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    • v.9 no.8
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    • pp.41-50
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    • 2018
  • Purpose - As an important participant in the financial markets, the commercial bank will be impacted by the interest rate marketization. Owing to the special condition of China, this paper tries to explore the impact of operating mechanisms between interest rate marketization and the profitability of the commercial Bank. Research design, data and methodology - This paper applies time series data from 2005 to 2016. Due to the short period of time series, autocorrelation often occurs. Therefore, the fully modified least squares(FMOLS) will be used to conduct an empirical analysis. The reason is that it can move off the autocorrelation between variables and disturbance term. And FMOLS also can make estimated cointegrating parameters closed to normal distribution. More importantly, in order to avoid spurious regressions, the Augmented Dickey-Fuller Test will be used to verify the stationarity of all variables. The total return of asset is treated as the profitability of commercial bank. The net interest spread is treated as a measurement of interest rate marketization. Both are regarded as dependent variables. The non-interest income or gross revenues and impaired loans or gross loans are treated as independent variables. The sixteen representative listed commercial banks are divided into three categories (state-owned, share-holding and city-owned) to conduct an estimation. Results - Via empirical analysis, the findings show that the net interest spread has a positive effect on the profitability of the commercial bank. More specifically, 1% increase in the net interest spread will lead 0.157% increase in the profitability of state-owned commercial bank, 0.269% increase in the profitability of share-holding commercial bank and 0.263% increase in the profitability of city-owned commercial bank. If regarding the sixteen listed commercial city as a whole, 1% increase in the net interest spread will lead 0.267% increase in the profitability of the commercial bank. Conclusions - As the interest rate marketization, the importance of interest rate on the profitability of commercial bank has become more and more significant. The empirical evidences also prove that the net interest spread can bring about the change of the commercial bank's profitability. Therefore, policy-makers of commercial banks should fully understand the operating mechanism between them.

Behavior of Bearing Capacity for Shallow Foundation on a Sand overlying Clay Depending on Bearing Capacity Ratio (점토층 위 모래지반의 지지력비에 따른 얕은 기초의 지지력 거동)

  • Jung, Min Hyung;Shin, Hyo Hee;Lee, Song
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.1
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    • pp.198-208
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    • 2011
  • When a structure which has relatively low load constructs on soft clay, the bearing capacity of the ground will be improved by sand overlying clay. In this condition, verifying the bearing capacity is difficult from the P.B.T etcetera in the in-situ. So, it is needed to estimate precise bearing capacity in the design process. In this study, 2-dimensional chamber tests and FEM analyses are conducted to evaluate behavior of bearing capacity for shallow foundations on a sand overlying clay. Because depth ratio H/B and bearing capacity ratio $q_c/q_s$ are selected as main factors, height of a sand, undrained shear strength of a clay and width of a loading are designated as variables. Results from chamber tests are very similar with those of FEM analyses. And it shows that punching shear mechanism is more suitable than the equation of Okamura et al.(1998). To make continual application of load spread mechanism, the equivalent load spread angle is proposed for H/B and $q_c/q_s$. Also, the linear regression equation of critical depth ratio Hf is suggested for $q_c/q_s$.

Clinical Microscopy: Performance, Maintenance and Laser Safety (임상에서의 현미경: 작동, 유지보수 및 레이저 안전)

  • Lee, Tae Bok
    • Korean Journal of Clinical Laboratory Science
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    • v.51 no.2
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    • pp.125-133
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    • 2019
  • A microscope is the fundamental research and diagnostic apparatus for clinical investigation of signaling transduction, morphological changes and physiological tracking of cells and intact tissues from patients in the biomedical laboratory science. Proper use, care and maintenance of microscope with comprehensive understanding in mechanism are fully requested for reliable image data and accurate interpretation for diagnosis in the clinical laboratory. The standard operating procedure (SOP) for light microscopes includes performance procedure, brief information of all mechanical parts of microscopes with systematic troubleshooting mechanism depending on the laboratory capacity. Maintenance program encompasses cleaning objective, ocular lenses and inner optics; replacement and calibration of light source; XY sample stage management; point spread function (PSF) measurement for confocal laser scanning microscope (CLSM); quality control (QC) program in fluorescent microscopy; and systematic troubleshooting. Laser safety is one of the concern for medical technologists engaged in CLSM laboratory. Laser safety guideline based on the laser classification and risk level, and advisory lab wear for CLSM users are also expatiated in this overview. Since acquired image data presents a wide range of information at the moment of acquisition, well-maintained microscopes with proper microscopic maintenance program are impulsive for its interpretation and diagnosis in the clinical laboratory.

An Intelligent Video Streaming Mechanism based on a Deep Q-Network for QoE Enhancement (QoE 향상을 위한 Deep Q-Network 기반의 지능형 비디오 스트리밍 메커니즘)

  • Kim, ISeul;Hong, Seongjun;Jung, Sungwook;Lim, Kyungshik
    • Journal of Korea Multimedia Society
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    • v.21 no.2
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    • pp.188-198
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    • 2018
  • With recent development of high-speed wide-area wireless networks and wide spread of highperformance wireless devices, the demand on seamless video streaming services in Long Term Evolution (LTE) network environments is ever increasing. To meet the demand and provide enhanced Quality of Experience (QoE) with mobile users, the Dynamic Adaptive Streaming over HTTP (DASH) has been actively studied to achieve QoE enhanced video streaming service in dynamic network environments. However, the existing DASH algorithm to select the quality of requesting video segments is based on a procedural algorithm so that it reveals a limitation to adapt its performance to dynamic network situations. To overcome this limitation this paper proposes a novel quality selection mechanism based on a Deep Q-Network (DQN) model, the DQN-based DASH ABR($DQN_{ABR}$) mechanism. The $DQN_{ABR}$ mechanism replaces the existing DASH ABR algorithm with an intelligent deep learning model which optimizes service quality to mobile users through reinforcement learning. Compared to the existing approaches, the experimental analysis shows that the proposed solution outperforms in terms of adapting to dynamic wireless network situations and improving QoE experience of end users.