Shipping universally accounts for 80% of global trade and 70% in price terms. While in Vietnam, not only the maritime transport market share, especially with international goods, has decreased significantly but also the maritime transport volume of national fleet tends to decrease. Therefore, the solutions of increasing the transport volume along with regaining the transport market share are a major concern for Vietnam's shipping development plan. With the purpose of finding these important solutions, this research aims at investigating the factors affecting the national fleet’s transport volume by ARDL model based on Vietnamese fleet’s transport volume quarterly data from 2008 to 2022. The results demonstrate that the deadweight tonnage of the fleet and GDP are the two fundamental factors which have positive influences on transport volume of Vietnamese shipping fleet in both the short run and the long run. Then, the paper proposes solutions how these two variables, especially the tonnage of the fleet increase the maritime transport market share as well. The findings provide clear directions to the policy makers and the shipping company in proposing relevant solutions for shipping development plan.

In olefin/paraffin separation process, new technology such as membrane separation process has been ever demanding for both economic and environmental reasons. facilitated olefin transport membrane, containing positively charged silver nanoparticles (Ag NPs) by electron acceptor 7,7,8,8-tetracyanoquinodimethane (TCNQ) as olefin carriers dispersed in poly(vinyl pyrrolidone) (PVP), shows extremely high separation performance for propylene/propane mixtures. However, higher permeance is always demanding for practical applications. In this study, POSSs were added to PVP/Ag NPs/TCNQ membranes. Among various kinds of POSS, trisilanolisooctyl POSS showed higher permeance with a moderate selectivity. Therefore it is concluded that mesoporous POSS is an effective additive in improving the gas permeance.

해수의 수송이 바다목장화 해역에 미치는 영향을 알아보기 위하여 조석과 바람, 수온 및 염분의 효과를 고려한 해수 유동 모델을 관측한 자료를 토대로 하여 구축하였다. 현장 관측 결과 중층에서 유속이 가장 강하게 나타났으며, 조화분해 결과 반일주조가 강한 혼합조의 형 태로 나타났다. 조류 효과만을 고려하였을 경우, 해수는 어류목장에서 갑각류목장으로, 갑각류목장에서 패류목장으로 수송되었다. 조석과 바람, 수온 및 염분의 효과를 고려한 잔차류의 경우에는 어류목장에서 갑각류목장으로, 패류목장에서 갑각류목장으로 해수가 수송되었다. 한편, 해수 의 최대 수송은 조류나 잔차류의 2가지의 경우 모두가 동일하게 어류목장에서 갑각류목장으로 이동할 때 나타났다.

고정확도를 보장할 수 있는 Compact Finite Volume Method를 이용하여 수심적분형 흐름 모형과 수심평균된 이송확산방정식을 해석하는 수치모형 개발과정을 기술하였다. 이차원의 흐름과 파랑의 상호작용에 대한 실험결과와 제시된 수치모형을 이용한 계산결과는 양호하게 일치하였다. 일차원과 이차원공간에서의 흐름에 의한 스칼라의 이송에 관한 수치모의에서도 수차확산이 거의 발견되지 않았고, 매우 정확히 일치하였다. 개수로에서의 난류혼합에 관한 수치모의 결과에서도 합리적인 스칼라의 혼합양상이 관찰되었다.

The volume transport and turnover time of the Deukryang Bay, located at the southern area of Korea, were calculated based on the current meter(RCM-7,ACM 16M) data observed at the three gateways of the Bay in May and October of 1996. Dominant tidal current component was calculated through harmonic analysis from raw data to estimate influence tidal current and also residual current was measured by integrating observed data and then averaging on time. Maximum speed of current was about 100㎝/sec during the spring tide at the waterway between Kumdangdo and Kogumdo. The total water volume transports through three entrances of the bay in May and October were 3.9×10^-2 Sv, 3.4×10^-2 Sv(1Sv=10^6㎥s^-1) and turnover time were 0.97day, 1.12day, respectively. Semidiurnal tides were predominant (70∼85%). The water volume transports by residual currents were 2∼4% of total water volume transports. The average fraction of fresh water calculated by tidal prism method using salinity difference between inflow current and outflow current through three entrances in Deukryang Bay was about 0.06% of total volume and the flushing time of fresh water was estimated as 0.97day.