• 제목/요약/키워드: Non-structure

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Seismic design of structures using a modified non-stationary critical excitation

  • Ashtari, P.;Ghasemi, S.H.
    • Earthquakes and Structures
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    • 제4권4호
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    • pp.383-396
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    • 2013
  • In earthquake engineering area, the critical excitation method is an approach to find the most severe earthquake subjected to the structure. However, given some earthquake constraints, such as intensity and power, the critical excitations have spectral density functions that often resonate with the first modes of the structure. This paper presents a non-stationary critical excitation that is capable of exciting the main modes of the structure using a non-uniform power spectral density (PSD) that is similar to natural earthquakes. Thus, this paper proposes a new method to estimate the power and intensity of earthquakes. Finally, a new method for the linear seismic design of structures using a modified non-stationary critical excitation is proposed.

ZnO 소자의 비직선 특성 (The Non-Linear Characteristics of ZnO Devices.)

  • 홍경진;전경남;조재철
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 춘계학술대회 논문집 센서 박막재료
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    • pp.43-46
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    • 2001
  • The ZnO devices using semiconductor properties, to include $MnO_2$, $Y_2O_3$ and other material, was fabricated by $Sb_2O_3$ mol ratio from 1 to 4 [mol%]. The non-linearity factor was calculated by setting current to be $1[mA/cm^2]$ and $10[mA/cm^2]$. The spinel structure was fonned by $Sb_2O_3$ addition and it was depressed the ZnO grain formation. The grain growing was controlled by spinel structure that has improved the non-linearity factors. The breakdown voltage characteristics of semiconductor devices to increase with $Sb_2O_3$ was increased in voltage-current. The non-linearity value of ZnO semiconductor devices was 45 over.

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주파수응답 분리방법을 이용한 비접촉식 AFM (Non-contact type AFM using frequency separation scheme)

  • 이성규;염우섭;박기환;송기봉;김준호;김은경;박강호
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.375-378
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    • 2002
  • In this paper, the frequency response separation scheme is proposed for high scanning speed and simple structure of non-contact type of AFM. A self-sensing cantilever is attached on the actuator for detect the atomic force between tip and the media surface. VCM or PZT are used for actuator. This paper presents the method to simplify the actuator structure and the performance of each actuator for non-contact type AFM. Based on the frequency response separation scheme, the only one actuator plays roles 1311owing low frequency surface and modulating self-sensing cantilever tip in contrast with convention non-contact type AFM. 10 ${\mu}{\textrm}{m}$ standard grid sample imaged to verify proposed scheme. This result shows the possibility simplifying the actuator structure and reducing cost of non-contact type AFM.

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구조물의 비접촉 비파괴 검사를 위한 레이저 초음파법 적용 (A Structure Non-Contact and Non-destructive Evaluation Using Laser-Ultrasonics Application)

  • 김재열;송경석;양동조;김유홍
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2005년도 춘계학술대회 논문집
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    • pp.71-76
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    • 2005
  • The defects evaluation of the interior and the surface would be considered as vital characteristics in predicting the total life span of the steel structure. More importantly, the understandings in the interior composite of welding zone and the notifications in the presence, the formation, and the positioning of the non-metallic inclusion are necessary as well, since there were signs of relatively high defect frequency presented in the welding zone. The ultrasonic testing is a highly recommended technique chosen from among other techniques because of variety of advantages in conducting the non-destructive testing for the welding zone. However, the ultrasonic testing had technical disadvantages referred as followings; the problems due to the couplant between the PZT and the specimen, the formations that were miniature and complex, the moving subject, and the high temperature surrounding the specimen. This research was conducted to resolve the technical disadvantages of the contact ultrasonic testing by studying the non-contact ultrasonic testing where the ultrasonic waves were transferred by the laser, and revealing the specimen defects at its interior part and its surface part. The ultimate goal of this research was to develop a non-destructive evaluation applying the laser manipulated ultrasonic method for the steel structure.

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The Tumor Suppressor, p53, Negatively Regulates Non-Canonical NF-κB Signaling through miRNA-Induced Silencing of NF-κB-Inducing Kinase

  • Jang, Hanbit;Park, Seulki;Kim, Jaehoon;Kim, Jong Hwan;Kim, Seon-Young;Cho, Sayeon;Park, Sung Goo;Park, Byoung Chul;Kim, Sunhong;Kim, Jeong-Hoon
    • Molecules and Cells
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    • 제43권1호
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    • pp.23-33
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    • 2020
  • NF-κB signaling through both canonical and non-canonical pathways plays a central role in immune responses and inflammation. NF-κB-inducing kinase (NIK) stabilization is a key step in activation of the non-canonical pathway and its dysregulation implicated in various hematologic malignancies. The tumor suppressor, p53, is an established cellular gatekeeper of proliferation. Abnormalities of the TP53 gene have been detected in more than half of all human cancers. While the non-canonical NF-κB and p53 pathways have been explored for several decades, no studies to date have documented potential cross-talk between these two cancer-related mechanisms. Here, we demonstrate that p53 negatively regulates NIK in an miRNA-dependent manner. Overexpression of p53 decreased the levels of NIK, leading to inhibition of the non-canonical NF-κB pathway. Conversely, its knockdown led to increased levels of NIK, IKKα phosphorylation, and p100 processing. Additionally, miR-34b induced by nutlin-3 directly targeted the coding sequences (CDS) of NIK. Treatment with anti-miR-34b-5p augmented NIK levels and subsequent non-canonical NF-κB signaling. Our collective findings support a novel cross-talk mechanism between non-canonical NF-κB and p53.

용접구조물의 최신 비파괴 검사기술 (Latest Technology of Non Destructive Inspection for Welded Structure)

  • 김영식;길상철
    • Journal of Welding and Joining
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    • 제35권2호
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    • pp.63-70
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    • 2017
  • As the Non Destructive Test (NDT) for the welded structure, PT(Penetration Test). MT(Magnetic Test), RT (Radioisotope Test) and UT(Ultrasonic Test) methods are widely used in practice. These NDT methods have been developed toward high efficiency, low cost, real time, and high precise new NDT. For example, RT methods are developed to CT(Computed Tomography)and DR(Digital Radiography), and UT metheds are developed into Phased array, Guide wave, TOFD method. Moreover, the Infrared thermography and Laser ultrasonic technique are newly developed for applying in high temperature objects as the non-contact NDT methods. In this review paper the new high efficiency NDT methods for the welded structure are introduced and the trend of NDT rules applying in welded structure are described.

선수 플레어 구조손상 해석 (Damage Analysis of Bow-Flare Structure)

  • 김용직;신기석;신찬호;강점문;김만수;김성찬;오수관;임채환;김대헌
    • 대한조선학회논문집
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    • 제40권3호
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    • pp.37-44
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    • 2003
  • In rough seas, bow-flare regions of the sea-going ships are subject to high impact pressures due to the bow-flare slamming and panting. And many ships suffer structural damages in that region, even though they were built under the bow structure strengthening rules of the ship classes. So, a new design method for bow-flare structure is highly required. In this paper, bow-flare damage analysis is performed for 17 ships (total number of damage/non-damage data is 782). Based on this analysis, a new design standard and method for bow-flare structure (shell plate, frame and web frame) is proposed. 80.4% of the present damage/non-damage data were well-explained by this new design standard.

Seismic performance of secondary systems housed in isolated and non-isolated building

  • Kumar, Pardeep;Petwal, Sandeep
    • Earthquakes and Structures
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    • 제16권4호
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    • pp.401-413
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    • 2019
  • The concept of base isolation for equipment is well known. Its application in buildings and structures is rather challenging. Introduction of horizontal flexibility at the base helps in proper energy dissipation at the base level thus reducing the seismic demand of the super structure to be considered during design. The present study shows the results of a series of numerical simulation studies on seismic responses of secondary system (SS) housed in non-isolated and base-isolated primary structures (PS) including equipment-structure interactions. For this study the primary structure consists of two similar single bay three-store reinforced cement concrete (RCC) Frame building, one non-isolated with conventional foundation and another base isolated with Lead plug bearings (LPB) constructed at IIT Guwahati, while the secondary system is modeled as a steel frame. Time period of the base isolated building is higher than the fixed building. Due to the presence of isolator, Acceleration response is significantly reduced in both (X and Y) direction of Building. It have been found that when compared to fixed base building, the base isolated building gives better performance in high seismic prone areas.

EDGE-MINIMIZATION OF NON-DETERMINISTIC FINITE AUTOMATA

  • Melnikov, B.F.;Melnikova, A.A.
    • Journal of applied mathematics & informatics
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    • 제8권3호
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    • pp.693-703
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    • 2001
  • In this paper we consider non-deterministic finite Rabin-Scott’s automata. We use a special structure to descibe all the possible edges of non-determinstic finite automaton defining the given regular language. Such structure can be used for solving various problems of finite automata theory. One of these problems is edge-minimization of non-deterministic automata. As we have not touched this problem before, we obtain here two versions of the algorithm for solving this problem to continue previous series of articles.

Corporate Capital Structure Adjustments: Evidence from Vietnam Stock Exchange Market

  • NGUYEN, Cuong Thanh;BUI, Cuong Manh;PHAM, Tuan Dinh
    • The Journal of Asian Finance, Economics and Business
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    • 제6권3호
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    • pp.41-53
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    • 2019
  • Building a target capital structure is one of the most important decisions in corporate financial management. The purpose of this article is to identify the determinants of capital structure and adjustment mechanism toward the target leverage. The partial adjustment model was applied on a sample of 306 non-financial companies listed on Vietnam stock exchange market during the period of 2008-2017. By the fixed effect model estimation method, the research results have discovered the factors of growth opportunities, firm size, tangible fixed assets and firm's unique characteristics have a positive effect on the target capital structure of enterprises. Besides, profitability and dividend payment have a negative effect on the target capital structure of enterprises. Accordingly, the research results show that the average adjustment speed toward target leverage of the firms is 90.03%. Research results also demonstrate firms have higher or lower debt ratio than the target debt ratio, capital surplus or capital deficit also have an impact on the adjustment rate toward the target capital structure. The research results are consistent with the Dynamic Trade-off Theory. From this result, this article has provided policy implications for non-financial companies listed on Vietnam's stock market in building a reasonable target capital structure according to operating timeline to maximize enterprise value.