새만금 호의 수질 개선을 위하여 국가에서 해수 유통을 증가시킴에 따라 해수 유통 빈도 증가로 인한 새만금 호 내 염분과 저 층수 교환 변화를 알아보기 위하여, EFDC(Environmental Fluid Dynamics Code) 모델을 이용하였다. 갑문 개폐 횟수를 하루 1회에서 2회로 증 가했을 때, 새만금 호 내부 수위는 최대 약 0.7 m 상승하였다. 염분은 서측 방조제 근방에서 2.12 psu 증가하였으며, 담수 유입 부근에서는 1.18 psu 감소하였다. 입자추적을 이용하여 저층수 교환 정도 분석한 결과, 수심 5m 이하 입자 잔류율은 Case 2(1일 2회 개방)에서 Case 1(1 일 1회 개방)에 비해 2.52% 감소한 것으로 나타났다. 이는 수문 개폐 횟수를 증가시켰을 때, 저층수 교환이 더 활발해 질 수 있다는 것을 알 수 있다. 따라서 해수 유통 증가에 따른 염분 및 저층수 교환 증가로 새만금 호의 수질 개선이 될 수 있다고 판단된다.

Since the interaction between the second-phase particle and grain boundary was theoretically explained by Zener and Smith in the late 1940s, the interaction of the second-phase particle and grain boundary on the microstructure is commonly referred to as Zener pinning. It is known as one of the main mechanisms that can retard grain growth during heat treatment of metallic and ceramic polycrystalline systems. Computer simulation techniques have been applied to the study of microstructure changes since the 1980s, and accordingly, the second-phase particle–grain boundary interaction has been simulated by various simulation techniques, and further diverse developments have been made for more realistic and accurate simulations. In this study, we explore the existing development patterns and discuss future possible development directions.

We have developed a cosmological N-body code which can simulate unprecedently large number of massive particles. This code is based on the Particle-Mesh scheme, and utilize the recent fast I/O devices to swap all variables. Using the new code we have simulated the formation and evolution of structures at high redshifts in the standard Cold Dark Matter (CDM) cosmogony. A simulation evolving 1024^3 particles on a 2048^3 mesh with the initial standard CDM power spectrum is being made. This is the first billion particle cosmological simulation with initial conditions representing the theoretical model over the widest range of space. A smaller, but still very large CDM simulation with 512^3 particles on a 1024^3 mesh has been completed. We have found that the galaxy-scale CDM halos with diameters of tens of kpcs undergo complete collapse before redshift 10. Our results clearly indicate that galactic and subgalactic structures have formed far before redshift 5 which is the present upper limit to the epoch of observed structures. We emphasize that the non-linear evolution of the galactic and subgalactic-scale structures starts as early as z ~ 50, and that cosmological simulations must start at such high redshifts. A high mass resolution is also indispensable to accurately represent the theoretical model in the initial conditions down to subgalactic scales, and to correctly study the subsequent formation and evolution of structures through hierarchical clustering.