• KCI Concrete Journal
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• 제13권1호
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• pp.11-17
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• 2001

The purpose of this state-of-the-art paper is to explore several important methods thor obtaining the equivalent loads in prestressed concrete structures. and to clarify the theoretical basis and implied assumptions of each method. The method devised in this stuffily include the use of curvature of tendon, characteristics of primary moment, self-equilibrium condition and linear segments approximation of tendon. It is shown that equivalent loading system it not uniquely determined depending on the approach adopted to calculate the equivalent loads. Self-equilibrium conditions of the equivalent loading system are carefully discussed. Numerical examples are presented to show the differences among the methods arid results of the approximations in each method explicitly.

• Kyungpook Mathematical Journal
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• 제64권1호
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• pp.69-94
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• 2024

In this paper, we introduce an inertial self-adaptive projection method using Bregman distance techniques for solving pseudomonotone equilibrium problems in reflexive Banach spaces. The algorithm requires only one projection onto the feasible set without any Lipschitz-like condition on the bifunction. Using this method, a strong convergence theorem is proved under some mild conditions. Furthermore, we include numerical experiments to illustrate the behaviour of the new algorithm with respect to the Bregman function and other algorithms in the literature.

• 대한수학회지
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• 제34권3호
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• pp.731-770
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• 1997

We study Diriclet forms and related subjects for the Gibbs measures of classical unbounded sping systems interacting via potentials which are superstable and regular. For any Gibbs measure $\mu$, we construct a Dirichlet form and the associated diffusion process on $L^2(\Omega, d\mu), where \Omega = (R^d)^Z^\nu$. Under appropriate conditions on the potential we show that the Dirichlet operator associated to a Gibbs measure $\mu$ is essentially self-adjoint on the space of smooth bounded cylinder functions. Under the condition of uniform log-concavity, the Gibbs measure exists uniquely and there exists a mass gap in the lower end of the spectrum of the Dirichlet operator. We also show that under the condition of uniform log-concavity, the unique Gibbs measure satisfies the log-Sobolev inequality. We utilize the general scheme of the previous works on the theory in infinite dimensional spaces developed by e.g., Albeverio, Antonjuk, Hoegh-Krohn, Kondratiev, Rockner, and Kusuoka, etc, and also use the equilibrium condition and the regularity of Gibbs measures extensively.

• Wind and Structures
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• 제24권5호
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• pp.465-480
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• 2017

Modelling an equilibrium atmospheric boundary layer (ABL) in computational wind engineering (CWE) and relevant areas requires the boundary conditions, the turbulence model and associated constants to be consistent with each other. Among them, the inflow boundary conditions play an important role and determine whether the equations of the turbulence model are satisfied in the whole domain. In this paper, the idea of modeling an equilibrium ABL through specifying proper inflow boundary conditions is extended to the SST $k-{\omega}$ model, which is regarded as a better RANS model for simulating the blunt body flow than the standard $k-{\varepsilon}$ model. Two new sets of inflow boundary conditions corresponding to different descriptions of the inflow velocity profiles, the logarithmic law and the power law respectively, are then theoretically proposed and numerically verified. A method of determining the undetermined constants and a set of parameter system are then given, which are suitable for the standard wind terrains defined in the wind load code. Finally, the full inflow boundary condition equations considering the scale effect are presented for the purpose of general use.

• EDISON SW 활용 경진대회 논문집
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• 제3회(2014년)
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• pp.457-458
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• 2014

In this paper, quantum mechanical simulations of the double-gate ultra-thin body (DG-UTB) MOSFETs are performed according to the International Technology Roadmap of Semiconductors (ITRS) specifications planned for 2020, to devise the way for on-current ($I_{on}$) improvement. We have employed non-equilibrium Green's function (NEGF) approach and solved the self-consistent equations based on the parabolic effective mass theory [1]. Our study shows that the [100]/<001> Ge and GaSb channel devices have higher $I_{on}$ than Si channel devices under the body thickness ($T_{bd}$) <5nm condition.

• Structural Engineering and Mechanics
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• 제87권3호
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• pp.255-272
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• 2023

Spatial cable systems can provide more transverse stiffness and torsional stiffness without sacrificing the vertical bearing capacity compared with conventional vertical cable systems, which is quite lucrative for long-span earth-anchored suspension bridges' development. Higher economy highlights the importance of refined form-finding analysis. Meanwhile, the internal connection between the lateral and vertical sags has not yet been specified. Given this, an analytic algorithm of form-finding for the earth-anchored suspension bridge with spatial cables is proposed in this paper. Through the geometric compatibility condition and mechanical equilibrium condition, the expressions for cable segment, the recurrence relationship between catenary parameters and control equations of spatial cable are established. Additionally, the nonlinear general reduced gradient method is introduced into fast and high-precision numerical analysis. Furthermore, the analytic expression of the lateral and vertical sags is deduced and discussed. This is very significant for the space design above the bridge deck and the optimization of the sag-to-span ratio in the preliminary design stage of the bridge. Finally, the proposed method is verified with the aid of two examples, one being an operational self-anchored suspension bridge (with spatial cables and a 260 m main span), and the other being an earth-anchored suspension bridge under design (with spatial cables and a 500 m main span). The necessity of an iterative calculation for hanger tensions on earth-anchored suspension bridges is confirmed. It is further concluded that the main cable and their connected hangers are in very close inclined planes.

• Journal of Microbiology and Biotechnology
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• 제17권12호
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• pp.2027-2032
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• 2007

[ ${\alpha}$ ]-Synuclein is the major component of Lewy bodies and responsible for the amyloid deposits observed in Parkinson's disease. Ordered filamentous aggregate formation of the natively unfolded ${\alpha}$-synuclein was investigated in vitro with the periodic ultrasonication. The ultrasonication induced the fibrillation of ${\alpha}$-synuclein, as the random structure gradually converted into a ${\beta}$-sheet structure. The resulting fibrils obtained at the stationary phase appeared heterogeneous in their size distribution, with the average length and height of $0.28\;{\mu}m{\pm}0.21\;{\mu}m$ and $5.6\;nm{\pm}1.9\;nm$, respectively. After additional extensive ultrasonication in the absence of monomeric ${\alpha}$-synuclein, the equilibrium between the fibril formation and its breakdown shifted to the disintegration of the preexisting fibrils. The resulting fragments served as nucleation centers for the subsequent seed-dependent accelerated fibrillation under a quiescent incubation condition. This self-seeding amplification process depended on the seed formation and subsequent alterations in their properties by the ultrasonication to a state that accretes the monomeric soluble protein more effectively than their reassociation of the seeds back to the original fibrils. Since many neurodegenerative disorders have been considered to be propagated via the seed-dependent amyloidosis, this study would provide a novel aspect of the significance of the seed structure and its properties leading to the acce]erated amyloid formation.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2018년도 춘계학술대회 논문집
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• pp.102-102
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• 2018

Electronic industry had required the finer size and the higher performance of the device. Therefore, 3-D die stacking technology such as TSV (through silicon via) and micro-bump had been used. Moreover, by the development of the 3-D die stacking technology, 3-D structure such as chip to chip (c2c) and chip to wafer (c2w) had become practicable. These technologies led to the appearance of HBM (high bandwidth memory). HBM was type of the memory, which is composed of several stacked layers of the memory chips. Each memory chips were connected by TSV and micro-bump. Thus, HBM had lower RC delay and higher performance of data processing than the conventional memory. Moreover, due to the development of the IT industry such as, AI (artificial intelligence), IOT (internet of things), and VR (virtual reality), the lower pitch size and the higher density were required to micro-electronics. Particularly, to obtain the fine pitch, some of the method such as copper pillar, nickel diffusion barrier, and tin-silver or tin-silver-copper based bump had been utillized. TCB (thermal compression bonding) and reflow process (thermal aging) were conventional method to bond between tin-silver or tin-silver-copper caps in the temperature range of 200 to 300 degrees. However, because of tin overflow which caused by higher operating temperature than melting point of Tin ($232^{\circ}C$), there would be the danger of bump bridge failure in fine-pitch bonding. Furthermore, regulating the phase of IMC (intermetallic compound) which was located between nickel diffusion barrier and bump, had a lot of problems. For example, an excess of kirkendall void which provides site of brittle fracture occurs at IMC layer after reflow process. The essential solution to reduce the difficulty of bump bonding process is copper to copper direct bonding below $300^{\circ}C$. In this study, in order to improve the problem of bump bonding process, copper to copper direct bonding was performed below $300^{\circ}C$. The driving force of bonding was the self-annealing properties of electrodeposited Cu with high defect density. The self-annealing property originated in high defect density and non-equilibrium grain boundaries at the triple junction. The electrodeposited Cu at high current density and low bath temperature was fabricated by electroplating on copper deposited silicon wafer. The copper-copper bonding experiments was conducted using thermal pressing machine. The condition of investigation such as thermal parameter and pressure parameter were varied to acquire proper bonded specimens. The bonded interface was characterized by SEM (scanning electron microscope) and OM (optical microscope). The density of grain boundary and defects were examined by TEM (transmission electron microscopy).

• KDI Journal of Economic Policy
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• 제13권1호
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• pp.151-166
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• 1991

본고에서는 기존 독점생산자(獨占生産者)와 잠재적(潛在的) 신규참입자(新規參入者)간에 존재할 수 있는 진입제한(進入制限) 및 약탈가격(掠奪價格) 책정전략(策定戰略)을 간단한 복점(複占)게임모형(模型)을 통하여 분석한다. 분석(分析)으로부터 유도되는 대표적 결론(結論)은 생산여건(生産與件)에 관한 정보(情報)가 비대칭적(非對稱的)으로 분포되어 있을 경우 그 중 정보면에서 우월한 위치를 점하고 있는 생산자(生産者)가 잠재적(潛在的) 경쟁자(競爭者)를 불확실성하에 잡아 두려는 노력의 일환으로 진입제한가격(進入制限價格)이나 약탈가격(掠奪價格)을 책정할 수 있다는 점이다. 또 하나 본(本) 모형(模型)으로부터 얻을 수 있는 결론(結論)은 어느 독점생산자(獨占生産者)가 그의 독점적 위치를 지속적으로 지켜 나가기 위해 약탈가격(掠奪價格)을 책정하는 것만으로는 부족하다는 점이다. 그가 시장(市場)의 독점(獨占)을 효과적으로 유지해 나가기 위해서는 신규참입(新規參入)이 없는 경우에도 진입제한가격(進入制限價格)을 통하여 시장가격(市場價格)을 지속적으로 낮게 유지해야 한다. 이같은 결론은 진입제한가격(進入制限價格)과 약탈가격(掠奪價格)을 각각 분리해서 분석한 기존의 논의(論議)에는 결여되어 있는 것으로 약탈가격(掠奪價格)으로부터의 장기적 이익을 퇴출(退出) 이후의 독점이윤(獨占利潤)과 동일시하는 많은 분석들이 수정되어야 함을 의미한다. 진입제한(進入制限) 및 약탈가격(掠奪價格) 책정전략(策定戰略)이 합리적 이윤극대화전략(利潤極大化戰略)으로 성립할 수 있다고 하더라도 이것이 곧 이러한 기업행태(企業行態)에 관한 정부의 전면적인 금지조치(禁止措置)를 정당화하는 것은 아니다. 본고에서 일어나는 두가지 전략(戰略)은 오히려 복지증진적(福祉增進的)인 성격을 지니고 있으며 따라서 진입제한(進入制限) 및 약탈가격책정행위(掠奪價格策定行爲)의 규제(規制)는 사안별(事案別)로 신중히 다루어져야 함을 시사하고 있다.