• Title/Summary/Keyword: post-2012

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The effects of post nitriding on the AISI 316 stainless steel after Plasma carburizing at various gas compositions (저온 플라즈마침탄처리된 316L 스테인레스 스틸의 플라즈마 후질화 처리시 표면특성에 미치는 가스조성의 영향)

  • Lee, In-Seop;Debnath, Sanket
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2012.05a
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    • pp.177-178
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    • 2012
  • In this experiment, post-nitriding treatment has been performed at $400^{\circ}C$ on AISI 316 stainless steel which is plasma carburized previously at $430^{\circ}C$ for 15 hours. Plasma nitriding was implemented on AISI 316 stainless steel at various gas compositions (25% N2, 50% N2 and 75% N2) for 4 hours. Additionally, during post nitriding Ar gas was used with H2 and N2 to observe the improvement of treatment. After treatment, the behavior of the hybrid layer was investigated by optical microscopy, X-ray diffraction, and micro-hardness testing. Potentiodynamic polarization test was also used to evaluate the corrosion resistance of the samples. Meanwhile, it was found that the surface hardness increased with increasing the nitrogen gas content. Also small percentage of Ar gas was introduced in the post nitriding process which improved the hardness of the hardened layer but reduces the corrosion resistance compared with the carburized sample. The experiment revealed that AISI 316L stainless steel showed better hardness and excellent corrosion resistance compared with the carburized sample, when 75% N2 gas was used during the post nitriding treatment. Also addition of Ar gas during post nitriding treatment were degraded the corrosion resistance of the sample compared with the carburized sample.

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Post Keynesian Endogenous Money Theory and Banking Activity (포스트케인즈학파 내생화폐이론과 은행의 이중기능: 수평주의자와 구조주의자에 대한 새로운 이해)

  • Min, Byoung-Kil
    • 사회경제평론
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    • no.38
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    • pp.199-240
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    • 2012
  • According to the Post Keynesian endogenous money theory, money is created by the bank deposit which is dependent on the banks' supply of loan. And the demand for loans is dependent on investment by firms. In the money creating process, real value(or investment) and money are connected with banks' credit. In this paper, we investigated Keynes and Post Keynesian endogenous money theory with critical reviews of Hwang (2005). We came to three conclusions. First, Post Keynesian endogenous money theory is based on Keynes' theory. Second, Keynes' endogeneity of money is essentially different from that of Wicksellian. Third, focusing on the differences of the starting point of the arguments not on the conclusions, two Post Keynesian views, namely horizontalists and structuralists are compatible with liquidity preference theory in the Keynes' system.

A Case Report of Post-stroke Depression Patient Using Bunsimgi-eum(Fenxingiyin) (분심기음으로 호전된 뇌경색 후 우울증환자 치험 1례)

  • Ryu, Ho-Sun;Ahn, Hyo-Jin;Park, Se-Jin
    • The Journal of the Society of Stroke on Korean Medicine
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    • v.13 no.1
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    • pp.86-94
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    • 2012
  • Object : The purpose of this case report is to show an efficacy of Bunsimgi-eum(Fenxingiyin) for patient with Post-stroke Depression. Methods : This Patient was 64 year-old man who was diagnosed with Stroke by Brain MRI. And after the stroke, the patient showed some Post-stroke depression(PSD) behaviors, like mutism, waxy flexibility and have no willness of rehabilitation. He was treated by Herbal medicines, acupunctore and moxibustion therapy. 40 days after hospitalization, Bunsimgi-eum was prescribed to the patient. Results : After Bunsimgi-eum Herbal treatment, the symtoms of Post-stroke depression have improved remarkably. The grade of Rt. side hemiparesis and time of rehabilitation treat were also increased. Conclusions : This study suggests that Bunsimgi-eum could have a positive efficacy for Post-stroke depression. As a result, it makes the patient to take more rehabilitation treatment.

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Analytical approximate solution for Initial post-buckling behavior of pipes in oil and gas wells

  • Yu, Yongping;Sun, Youhong;Han, Yucen
    • Coupled systems mechanics
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    • v.1 no.2
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    • pp.155-163
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    • 2012
  • This paper presents analytical approximate solutions for the initial post-buckling deformation of the pipes in oil and gas wells. The governing differential equation with sinusoidal nonlinearity can be reduced to form a third-order-polynomial nonlinear equation, by coupling of the well-known Maclaurin series expansion and orthogonal Chebyshev polynomials. Analytical approximations to the resulting boundary condition problem are established by combining the Newton's method with the method of harmonic balance. The linearization is performed prior to proceeding with harmonic balancing thus resulting in a set of linear algebraic equations instead of one of non-linear algebraic equations, unlike the classical method of harmonic balance. We are hence able to establish analytical approximate solutions. The approximate formulae for load along axis, and periodic solution are established for derivative of the helix angle at the end of the pipe. Illustrative examples are selected and compared to "reference" solution obtained by the shooting method to substantiate the accuracy and correctness of the approximate analytical approach.

Post Silicon Management of On-Package Variation Induced 3D Clock Skew

  • Kim, Tak-Yung;Kim, Tae-Whan
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.12 no.2
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    • pp.139-149
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    • 2012
  • A 3D stacked IC is made by multiple dies (possibly) with heterogeneous process technologies. Therefore, die-to-die variation in 2D chips renders on-package variation (OPV) in a 3D chip. In spite of the different variation effect in 3D chips, generally, 3D die stacking can produce high yield due to the smaller individual die area and the averaging effect of variation on data path. However, 3D clock network can experience unintended huge clock skew due to the different clock propagation routes on multiple stacked dies. In this paper, we analyze the on-package variation effect on 3D clock networks and show the necessity of a post silicon management method such as body biasing technique for the OPV induced 3D clock skew control in 3D stacked IC designs. Then, we present a parametric yield improvement method to mitigate the OPV induced 3D clock skew.

Structural Health Monitoring of Aircraft Reciprocating Engine Based on Principal Component Analysis (PCA) (주성분 분석(PCA)에 의한 항공기 왕복 엔진의 구조 건전도 모니터링)

  • Kim, Ji-Hwan;Park, Seong-Eun;Lee, Hyeong-Cheol
    • Journal of Aerospace System Engineering
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    • v.6 no.1
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    • pp.13-18
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    • 2012
  • This paper presents a structural health monitoring method of aircraft reciprocating engine using Principal Component Analysis (PCA) which analyzes vibration expressed by Averaged Normalized Power Spectral Density (ANPSD). Because ANPSD of the rotating shaft is sensitive to the rotating speed, this paper proposes to use a post-processing method of ANPSD is used to reduce the sensitivity. The PCA extracts compressed information from the post-processed ANPSDs and the information means the difference between current and normal cases of the engine. The experimental results demonstrate the feasibility and effectiveness of the proposed method to detect abnormal cases of the engine.

Activation-induced Cytidine Deaminase in B Cell Immunity and Cancers

  • Park, Seok-Rae
    • IMMUNE NETWORK
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    • v.12 no.6
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    • pp.230-239
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    • 2012
  • Activation-induced cytidine deaminase (AID) is an enzyme that is predominantly expressed in germinal center B cells and plays a pivotal role in immunoglobulin class switch recombination and somatic hypermutation for antibody (Ab) maturation. These two genetic processes endow Abs with protective functions against a multitude of antigens (pathogens) during humoral immune responses. In B cells, AID expression is regulated at the level of either transcriptional activation on AID gene loci or post-transcriptional suppression of AID mRNA. Furthermore, AID stabilization and targeting are determined by post-translational modifications and interactions with other cellular/nuclear factors. On the other hand, aberrant expression of AID causes B cell leukemias and lymphomas, including Burkitt's lymphoma caused by c-myc/IgH translocation. AID is also ectopically expressed in T cells and non-immune cells, and triggers point mutations in relevant DNA loci, resulting in tumorigenesis. Here, I review the recent literatures on the function of AID, regulation of AID expression, stability and targeting in B cells, and AID-related tumor formation.

Co-ordination between R&D and Human Resource in the post catching-up era

  • Hwang, Gyu-Hee
    • International Journal of Contents
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    • v.8 no.3
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    • pp.42-51
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    • 2012
  • Korea has entered into the Post Catching-up era and the necessity of new innovation strategy in response is being raised. This study argues the necessity of new innovation strategy and discusses the issue of co-ordination between R&D and Human Resource for that as the key factor. From empirical analysis, there seems to be restricted inflow of outstanding human resources to manufacturing sectors and lowering effectiveness of major even with the improved compatibility between major and job. Especially, it is severe in the industries with high R&D investment. It can be interpreted as an incoordination of the technological innovation efforts from the aspect of R&D investment with human resource utilization from the aspect of new human resource. The analytical result and interpretation suggests that there should be more active improvement on the co-ordination between innovative manufacturers' efforts and human resource utilization, in order to keep sustainable development.

Development of an Intelligent Power Plant Operating State Monitoring System (발전소 설비 운영상태 지능감시 시스템 개발)

  • Hong, Chang-Ho;Kim, Seok-Hyun;Lee, Seung-Chul
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.1
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    • pp.38-43
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    • 2012
  • For safe and stable operations of power plants, it is essential to monitor closely crucial measurement values related to power plant trips. In this paper, an intelligent power plant operating state monitoring technique enabling the operating crew member to monitor conveniently the status of the important measurement values and to perceive almost instantly the significance of the implications of those measurement values is developed. The proposed technique is called a "POST(Plant Operating State Tracking) Chart" technique and provides the foundations in developing an intelligent and integrated power plant operating state monitoring support system called the "P-OASIS"(Plant Operation Assessment and Support Intelligent System). The P-OASIS is applied to a thermal power plant of 500[MW] capacity and exhibited impressive performances.

Mordanting effect of Chestnut's inner skin on the cow leather dyed with Turmeric powder (우피의 울금 염색시 사용된 율피의 매염 효과)

  • Bai, Sang-Kyoung
    • Journal of Fashion Business
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    • v.16 no.4
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    • pp.100-106
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    • 2012
  • This research was carried out to find the mordant effect of Chestnut's inner skin on the cow leather dyed by Turmeric powder. The best proper mordanting conditions were examined by changing mordant method, concentration, temperature, bath ratio, time, and repetition. Also dyeability and surface color changes were evaluated by various mordanting methods. The optimum mordanting conditions of chestnut's inner skin extract on the cow leather were pre mordant, 80%, $50^{\circ}C$, 50:1, 40minutes, 4 repetition. The K/S values as a mordant were higher in pre mordant than post mordanting condition. Although the ${\Delta}E$ was slightly higher in post mordant than pre mordant, it was too small to find any means. The surface colors of all dyed cow leathers were yellow. Among light, dry cleaning, and abrasion fastnesses, only light fastness was increased one degree, others were same degrees.