We introduce a depth scaling strategy to improve the accuracy of frequency-domain elastic full waveform inversion (FWI) using the new pseudo-Hessian matrix for seismic data without low-frequency components. The depth scaling strategy is based on the fact that the damping factor in the Levenberg-Marquardt method controls the energy concentration in the gradient. In other words, a large damping factor makes the Levenberg-Marquardt method similar to the steepest-descent method, by which shallow structures are mainly recovered. With a small damping factor, the Levenberg-Marquardt method becomes similar to the Gauss-Newton methods by which we can resolve deep structures as well as shallow structures. In our depth scaling strategy, a large damping factor is used in the early stage and then decreases automatically with the trend of error as the iteration goes on. With the depth scaling strategy, we can gradually move the parameter-searching region from shallow to deep parts. This flexible damping factor plays a role in retarding the model parameter update for shallow parts and mainly inverting deeper parts in the later stage of inversion. By doing so, we can improve deep parts in inversion results. The depth scaling strategy is applied to synthetic data without lowfrequency components for a modified version of the SEG/EAGE overthrust model. Numerical examples show that the flexible damping factor yields better results than the constant damping factor when reliable low-frequency components are missing.

Recently, a possibility of the surface treatment material is expected as an integrated control method for various degradations of concrete structure. However, as experimental results, although water permeability of the concrete could be improved due to the surface treatment material, the scaling of surface layer was accelerated under freezing and thawing cycles. Furthermore, the mechanism of scaling acceleration has not been clarified yet. Therefore, in order to clarify the mechanism accelerating the scaling of the treated concrete, the behavior of variations in the moisture and ice contents in the concrete were investigated especially based on a simulation analysis using a simultaneous heat and moisture transfer equation for a three-phase system. The analysis simulated the freezing-thawing process in the RILEM CIF/CDF test. And the mechanism accelerating the scaling is discussed based on the differences of the freezing behavior due to the infiltration depth of the surface treatment material. As the results, in the case of the smaller infiltration depth, it has been clarified that the reason to accelerate the scaling is the increasing of the ice content at the boundary between the treated and untreated regions.

방송과 영화 등에서의 영상 기술의 발전은 최근 3차원 입체 영상에 대한 관심을 증가시켜 왔다. 뿐만 아니라 2차원 영상의 한계로 인하여 3차원 콘텐츠에서의 입체 영상 표현 기술 개발이 시간이 지날수록 더욱 활발해지고 있다. 이는 단지 방송 분야에 국한되는 것이 아니라 의료, 교육 등 다양한 분야에서 폭넓게 접할 수 있도록 입체 영상 기술이 개발, 연구되고 있다. 하지만 입체감 표현에 있어 필요한 정교한 연출과 입체감 인지에 따른 피로감 발생 등의 이유로 예측 불허로 변화하는 게임과 같은 실시간 시스템에서 입체 영상 기술의 접목은 거의 이루어지지 않고 있다. 본 논문에서는 DirectX SDK 그래픽 파이프라인의 기하학적 구조를 바탕으로 입체감을 효율적으로 다룰 수 있고 상황에 따른 자동 시점 간격 조정을 통해 피로감을 해결하는 깊이감 조절 기법을 설계하였다. 이를 통해 입체 영상 기술이 접목된 게임 제작이 활발히 이루어질수 있는 새로운 대안을 제시해보고자 한다.