• 제목/요약/키워드: Structural transformation

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The Economic Security System in the Conditions of the Powers Transformation

  • Arefieva, Olena;Tulchynska, Svitlana;Popelo, Olha;Arefiev, Serhii;Tkachenko, Tetiana
    • International Journal of Computer Science & Network Security
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    • 제21권7호
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    • pp.35-42
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    • 2021
  • In the article, the authors investigate the economic security system in the conditions of the powers transformation. It is substantiated that economic security acts as a certain system that includes components and at the same time acts as a subsystem of the highest order. It is determined that the economic security system of regions acting as a system has its subsystems, which include: production, financial, environmental, innovation, investment and social subsystems. The parameters of the economic security system include relative economic independence, economic stability and self-development of economic systems, and it is proved that an important feature of economic security in addition to its systemic nature is multi-vector. It is substantiated that the monitoring of ensuring the economic security system of the development of economic systems of different levels in the conditions of the powers transformation should contain the analysis of social, economic and ecological development of regions; spheres of possible dangers of the development of regional economic systems; the nature of the threats; the degree of the possibility of threats; time perspective of economic development threats; possible consequences of losses for economic entities; the impact of threats to the object of the economic entities' activity; possible asymmetry of economic development of regional economic entities. Possible threats as a consequence of the powers transformation have been identified. A PEST analysis of the impact of factors of different nature on economic security and the development of regional economic systems in the powers transformation is carried out. A recurrent ratio is proposed for the economic security system in the conditions of the powers transformation.

Probabilistic Reliability Assessment of Steel Frame with Leaning Columns

  • Vaclavel, Leo;Marek, Pavel
    • Computational Structural Engineering : An International Journal
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    • 제1권2호
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    • pp.97-106
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    • 2001
  • Safety and serviceability of a planar steel frame are assessed. Attention is turned to the individual main steps in the assessment procedure, i.e., to the definition of loads, selection of transformation model, determination of the response of the structure to the loading, and to the definition of the limiting values (considering safely and serviceability of the structure). The potential of the method using direct Monte Carlo technique as a powerful tool is emphasized.

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COMPARISON OF VARIABLE SELECTION AND STRUCTURAL SPECIFICATION BETWEEN REGRESSION AND NEURAL NETWORK MODELS FOR HOUSEHOLD VEHICULAR TRIP FORECASTING

  • Yi, Jun-Sub
    • Journal of applied mathematics & informatics
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    • 제6권2호
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    • pp.599-609
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    • 1999
  • Neural networks are explored as an alternative to a regres-sion model for prediction of the number of daily household vehicular trips. This study focuses on contrasting a neural network model with a regression model in term of variable selection as well as the appli-cation of these models for prediction of extreme observations, The differences in the models regarding data transformation variable selec-tion and multicollinearity are considered. The results indicate that the neural network model is a viable alternative to the regression model for addressing both messy data problems and limitation in variable structure specification.

상 변태를 고려한 HY-100강 용접부의 수축 및 잔류응력 예측에 관한 연구 (A Study on the Prediction of Shrinkage and Residual Stress for the HY-100 Weldment Considering the Phase Transformation)

  • 이희태;신상범
    • Journal of Welding and Joining
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    • 제25권1호
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    • pp.42-48
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    • 2007
  • For high performance and structural stability, application of high strength steel has continuously increased. However, the change of the base metal gives rise to problems with the accuracy management of the welded structure. It is attributed to the martensite phase transformation of the high strength low alloy steel weldment. The purpose of this study is to establish the predictive equation of transverse shrinkage and residual stress for the HY-100 weldment. In order to do it, high speed quenching dilatometer tests were performed to define a coefficient of thermal expansion(CTE) at the heating and cooling stage of HY-100 with various cooling rates. Uncoupled thermal-mechanical finite element(FE) models with CTE were proposed to evaluate the effect of the martensite phase transformation on transverse shrinkage and residual stresses at the weldment. FEA results were verified by comparing with experimental results. Based on the results of extensive FEA and experiments, the predictive equation of transverse shrinkage and longitudinal shrinkage force at the HY-100 weldment were formulated as the function of welding heat input/in-plane rigidity and welding heat input respectively.

형체력에 따른 사출성형기 플렉스링크의 특성 분석 (Characteristics Analysis of Flex Link according to Mold Clamping Force in Injection Molding Machine)

  • 정현석;유중학
    • 한국정밀공학회지
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    • 제31권2호
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    • pp.165-170
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    • 2014
  • Reproducibility of injection molding machines are studied at the study of this time. We applied computer aided engineering program so it could generate clamping force, about 1,500 kN, to the nozzle center part of flex link in tie-bar and at this time, we made sure condition of stress distribution and transformation quantity in flex link. The result of computer aided engineering transformation quantity was confirmed that transformation of top area was 247~257 kN and bottom areas was 273~279 kN and also was confirmed that the stresses are distributed in a range of 57~750 $N/mm^2$ from top to the bottom of the surface. This time we could confirm the condition of transformation quantity and stress distribution by enforcing the previously used structure analysis of flex link. And we utilized the reference data to establish important point of section for non destructive test overhaul.

탄소강 환봉의 레이저 표면변태경화 특성에 관한 연구 (I) - 가우시안 파워밀도 분포의 레이저 열원을 이용한 표면변태경화 특성 - (Study on Characteristics of Laser Surface Transformation Hardening for Rod-shaped Carbon Steel (I) - Characteristics of Surface Transformation Hardening by Laser Heat Source with Gaussian Intensify distribution -)

  • 김종도;강운주
    • Journal of Welding and Joining
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    • 제25권3호
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    • pp.78-84
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    • 2007
  • Laser Material Processing has been replaced the conventional machining systems - cutting, drilling, welding and surface modification and so on. Especially, LTH(Laser Transformation Hardening) process is one branch of the laser surface modification process. Conventionally, some techniques like a gas carburizing and nitriding as well as induction and torch heating have been used to harden the carbon steels. But these methods not only request post-machining resulted from a deformation but also have complex processing procedures. Besides, LTH process has some merits as : 1. It is easy to control the case depth because of output(laser power) adjustability. 2. It is able to harden the localized and complicated a.ea and minimize a deformation due to a unique property of a localized heat source. 3. An additional cooling medium is not required due to self quenching. 4. A prominent hardening results can be obtained. This study is related to the surface hardening of the rod-shaped carbon steel applied to the lathe based complex processing mechanism, a basic behavior of surface hardening, hardness distribution and structural characteristics in the hardened zone.

XML 문서의 빠른 변환을 위한 XSLT 스크립트 (XSLT Scripts for Fast XML Document Transformation)

  • 신동훈;이경호
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제11권6호
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    • pp.538-549
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    • 2005
  • 본 논문에서는 스키마를 구성하는 단말 노드 간의 일대일 매칭으로부터 XML 문서의 빠른 변환을 지원하는 XSLT 스크립트를 생성하는 방법을 제안한다. 제안된 방법은 XML 스키마를 구성하는 빈도 지시자 간의 대응관계 생성과 XSLT 스크립트 생성의 두 단계로 이루어진다. 어휘 및 구조 유사도를 이용하여 빈도 지시자 간의 대응관계를 생성하며 이를 바탕으로 적은 수의 템플릿을 포함하는 XSLT 스크립트를 생성한다. 성능을 평가하기 위하여 다양한 크기의 문서와 다수의 XSLT 처리기에 대해 실험한 결과, 제안된 방법은 기존 연구보다 XML 문서를 보다 빠르게 변환하는 XSLT 스크립트를 생성하였다.

Ginsenoside Rg3의 함량증가를 위한 변환 기술 (Transformation Techniques for the Large Scale Production of Ginsenoside Rg3)

  • 남기열;최재을;박종대
    • 한국약용작물학회지
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    • 제21권5호
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    • pp.401-414
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    • 2013
  • Ginsenoside Rg3 (G-Rg3) contained only in red ginseng has been found to show various pharmacological effects such as an anticancer, antiangiogenetic, antimetastastic, liver protective, neuroprotective immunomodulating, vasorelaxative, antidiabetic, insulin secretion promoting and antioxidant activities. It is well known that G-Rg3 could be divided into 20(R)-Rg3 and 20(S)-Rg3 according to the hydroxyl group attached to C-20 of aglycone, whose structural characteristics show different pharmacological activities. It has been reported that G-Rg3 is metabolized to G-Rh2 and protopanaxadiol by the conditions of the gastric acid or intestinal bacteria, thereby these metabolites could be absorbed, suggesting its absolute bioavailability (2.63%) to be very low. Therefore, we reviewed the chemical, physical and biological transformation methods for the production on a large scale of G-Rg3 with various pharmacological effects. We also examined the influence of acid and heat treatment-induced potentials on for the preparation method of higher G-Rg3 content in ginseng and ginseng products. Futhermore, the microbial and enzymatic bio-conversion technologies could be more efficient in terms of high selectivity, efficiency and productivity. The present review discusses the available technologies for G-Rg3 production on a large scale using chemical and biological transformation.

Digital Accounting, Financial Reporting Quality and Digital Transformation: Evidence from Thai Listed Firms

  • PHORNLAPHATRACHAKORN, Kornchai;NA KALASINDHU, Khajit
    • The Journal of Asian Finance, Economics and Business
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    • 제8권8호
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    • pp.409-419
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    • 2021
  • The study examines the effects of digital accounting on financial reporting quality, accounting information usefulness, and strategic decision effectiveness of listed firms in Thailand through digital transformation as the moderating variable. A total of 313 listed firms in Thailand were selected as the sample for the study. Structural equation model and multiple regression analysis are applied to test the research relationships. The results of the study show that digital accounting has a significant effect on financial reporting quality, accounting information usefulness, and strategic decision effectiveness. Financial reporting quality significantly affects both accounting information usefulness and strategic decision effectiveness while accounting information usefulness has a significant effect on strategic decision effectiveness. Both financial reporting quality and accounting information usefulness mediate the digital accounting-strategic decision effectiveness relationship. In addition, digital transformation moderates the digital accounting-financial reporting quality relationship and the digital accounting-accounting information usefulness relationship, but it does not moderate other relationships. Accordingly, digital accounting plays a significant role in determining and explaining firms' goal achievement. Executives are suggested to learn, invest and utilize the digital accounting system in the organization to ensure goal achievement and enhance organizational sustainability.

Wavelet 변환과 결합한 잔차 학습을 이용한 희박뷰 전산화단층영상의 인공물 감소 (Artifact Reduction in Sparse-view Computed Tomography Image using Residual Learning Combined with Wavelet Transformation)

  • 이승완
    • 한국방사선학회논문지
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    • 제16권3호
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    • pp.295-302
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    • 2022
  • 희박뷰 전산화단층촬영(computed tomography; CT) 영상화 기술은 피폭 방사선량을 감소시킬 수 있을 뿐만 아니라 획득한 투영상의 균일성을 유지하고 잡음을 감소시킬 수 있는 장점이 있다. 하지만 재구성 영상 내 인공물 발생으로 인하여 화질 및 피사체 구조가 왜곡되는 단점이 있다. 본 연구에서는 희박뷰 CT 영상의 인공물 감소를 위해 wavelet 변환과 잔차 학습(residual learning)을 적용한 콘볼루션 신경망(convolutional neural network; CNN) 기반 영상화 모델을 개발하고, 개발한 모델을 통한 희박뷰 CT 영상의 인공물 감소 정도를 정량적으로 분석하였다. CNN은 wavelet 변환 층, 콘볼루션 층 및 역 wavelet 변환 층으로 구성하였으며, 희박뷰 CT 영상과 잔차 영상을 각각 입출력 영상으로 설정하여 영상화 모델 학습을 진행하였다. 영상화 모델 학습을 위해 평균제곱오차(mean squared error; MSE)를 손실함수로, Adam 함수를 최적화 함수로 사용하였다. 학습된 모델을 통해 입력 희박뷰 CT 영상에 대한 예측 잔차 영상을 획득하고, 두 영상간의 감산을 통해 최종 결과 영상을 획득하였다. 또한 최종 결과 영상에 대한 시각적 특성, 최대신호대잡음비(peak signal-to- noise ratio; PSNR) 및 구조적유사성지수(structural similarity; SSIM)를 측정하였다. 연구결과 본 연구에서 개발한 영상화 모델을 통해 희박뷰 CT 영상의 인공물이 효과적으로 제거되며, 공간분해능이 향상되는 결과를 확인하였다. 또한 wavelet 변환과 잔차 학습을 미적용한 영상화 모델에 비해 본 연구에서 개발한 영상화 모델은 결과 영상의 PSNR 및 SSIM을 각각 8.18% 및 19.71% 향상시킬 수 있음을 확인하였다. 따라서 본 연구에서 개발한 영상화 모델을 이용하여 희박뷰 CT 영상의 인공물 제거는 물론 공간분해능 향상 및 정량적 정확도 향상 효과를 획득할 수 있다.