Various numerical models that have been developed for marine environments and applied to coastal waters in USA were introduced briefly. Inter alia, with regard to an integrated monitoring and modeling system, the main features and outline of system, the system architecture for data management and representation system, and the incorporation of internet based technology were described. An example of application of an integrated system to coastal waters was also presented. The prospective research works to improve the capabilities and to advance the functionality of an integrated monitoring, modeling and management system were suggested to be the instrumentations for various monitoring parameters, the new development and/or advancement of various numerical models, the relevant internet based technologies. etc..

Recently, as the coastal trading is being increased rapidly, risk of collision being increased especially in the coastal route near around the port of Wando. In this paper, with the reference to various literatures and papers on collision avoidance rules, the navigational rules and regulations for the coastal area-especially for the narrow channel-are construed and introduced in brief. Also, 3 collision cases near around the port of Wando and statistical data during 5 years(1996 to 2000) are studied. The results of this study are as follows; 1. It is strongly recommended to separate the route of east-bound and west-bound in this area due to removing the risk of collision between the vessels in reciprocal way. 2. The owner of the fleet should lead that the master should con the vessel by himself when passing this area. 3. For the introduction of the Coastal VTS, it is required to investigate the capability to cooperate with military radar sites which based on all over the coast.

Totally, twenty seven specimens of tiger puffer, Fugu rubripes rubripes were collected at Jagalchi fish market in Pusan, Korea during January, April and September in 1995. Anatomical distribution of pufferfish toxin in tiger puffer was examined by mouse bioassay. The frequency rate of toxic specimens containing ≥ 10 MU/g was 14.8% in liver; 16.7% in gonad; and 14.8% in skin, and no toxin was detected in muscle. The highest toxin level found was 160 MU/g in liver, 600 MU/g in gonad and 26 MU/g in skin, and each average toxin level (mean ± standard error) was 7 ± 6, 50 ± 35 and 5 ± 1 MU/g, respectively. Some specimens collected in January and April were toxic, while none of the specimens collected in September showed its toxicity. Although toxicity of tiger puffer showed the seasonal variation, tested tiger puffer was evaluated as a safe seafood for consumption, in that an acceptable level of toxin was found in the edible muscle and skin.

The in situ observations and the seawater analyses were conducted at all seasons from July 1996 to April 1999 for the purpose of describing the characteristics of seasonal variations of water quality in Mokpo harbour, Korea. Vertical stratification started to be formed in water column in spring, developed in summer and disappeared in fall. In summer, vertical density distribution of water column was found to be in stable structure with lower temperature and higher salinity of bottom water, and the vertical mixing of water between surface and bottom layers was restricted. In winter, however, surface water was found to be similar to bottom water in temperature and salinity, and water column was in unstable structure and in well-mixed condition between surface and bottom waters. The saturation percentage of dissolved oxygen(DO) in bottom water of inner part of Mokpo harbour at all seasons was shown to be decreased to the third grade or under the third grade of Korean standards of seawater quality. In particular, dissolved oxygen was oversaturated in surface water and undersaturated in bottom water in summer, due to stratification and organic pollution. The difference of DO concentration between surface and bottom waters was found to be greater in spring and summer than in fall and winter, due to stratification and photosynthesis of phytoplankton. The concentrations of chemical oxygen demand(COD) over the entire waters of Mokpo harbour were found to fluctuate from below the third grade to the first grade of Korean standards through all seasons and COD concentrations of same seasons were shown to be different year after year. In particular, in view of COD, the annual average seawater quality of Mokpo harbour was evaluated to be in third grade of Korean standards, due to organic pollution. The average COD of surface water was greater than that of bottom water in spring and summer, due to the autochthonous COD caused by production of phytoplankton in surface waters, while the average COD of surface water was similar to that of bottom water in fall and winter, due to the vertical mixing of water between surface and bottom layers.

The effect of β-heat treatment on th microstructure, mechanical properties and texture in the nuclear fuel cladding of Zircaloy-4 tubes was chosen at 1000, 1100 and 1200˚C, and the tubes were heat-treated by a high frequency vacuum induction furnace. Morphology of the second phase particles and α-grain of as-received tubes were markedly changed by heat treatment. The average sizes of second phase particles of as-received and β-heat treated tubes were 0.1μm and 0.076μm, respectively. However, the average sizes of second phase particles were not much changed in the β-heated temperatures. With increasing heat treatment temperatures, the 0.2% yield strength and the hoop strength were decreased because of changes in preferred orientation as will as α-plate width. Heat treated Zircaloy-4 tubes exhibited texture changes but the preferred orientation of grains still remained.

자동차용 캠 샤프트의 표면경화를 위해 TiG 용접공정에 의한 재용융처리가 실시되었다. 재용융처리는 캠축에 평행한 방향으로 행하여졌다. 캠 샤프트 소재의 조직은 편상의 흑연과 퍼얼라이트의 회주철 조직으로 구성되어 있으나 재용융 처리후 미세한 퍼얼라이트 및 세멘타이트와 구상 오스테나이트의 레데브라이트 조직으로 변화하였다. 캠 샤프트 모재의경도는 HRc 25~28에서 재용융 처리후에는 HRg 53~55정도로 증가하였다. 다층 용융 처리시 비드가 겹치는 경계에서 검은띠가 관찰되었는데 이 검은띠는 흑연으로 판명되었다. 이 검은띠는 전층의 레데브라이트 조직이 변태된 것으로 주로 세멘타이트와 기지조직의 경계에서 생성되었다. 고밀도 에너지인 레이저 용융처리시에도 재흑연화 현상은 TIG의 경우처럼 관찰되었다. 재흑연화 현상의 확인을 위해서 Gleeble 1500을 이용하여 1100˚C와 1000˚C에서 0.5, 1, 3, 5 및 10초동안 유지한 모의실험을 하였다. 1000˚C에서 0.5초 유지했을 때도 흑연이 발견된 것으로 보아 재흑연화 현상은 어떠한 재용융 처리 공정을 사용하더라도 피할 수 없는 현상임을 확인할 수 있다.

탈취온도가 옥수수기름의 냉각시험 및 발연점에 미치는 영향을 측정해 보았다. 탈취온도가 상승할수록 투입되는 탈납유 대비 탈취유의 냉각시험 결과는 현저히 하락하였으며, 260℃ 이상에서는 그 정도가 극심하여 이는 포화도 증가 및 SU_2, S_2U, S_3형 triglycerides 함량 증가와 상관관계가 있는 것으로 추측되었다. 한편, 발연점은 탈취온도 240℃에서 가장 높은 242℃를 나타내었고, 탈취온도 245∼270℃의 범위에서는 235∼238℃로 하락하였으며, 이러한 현상은 시료유의 산값과 반비례하는 것으로 나타났다. 따라서 일반 이화학적 특성, 지방산 조성 등과 함께 냉각시험 및 발연점에서도 고온탈취는 악영향을 미치는 것으로 판명되었다.

옥수수 글루텐을 식물성 효소인 파파인으로 가수분해하여 글루덴 펩타이드를 생산하였다. 생산된 글루텐 펩타이드류는 인이온 존재 하에서 인이온과 칼슘이온과의 침전형성을 방지하여 칼슘의 용해성을 증진시켰다. 칼슘이온의 용해도는 8.3㎎의 펩타이드 존재시 대조구에 비해 5.2배 증대되었다. 산성 아미노산의 함량이 매우 높은 이들 펩타이드류를 Delta pak 칼럼을 이용하여 분획하였으며 이들 분획가운데 3번째 분획이 가장 높은 칼슘 용해성을 보였다.

The in situ observations and the seawater analyses were conducted in July and Auguse, 1996 for the purpose of evaluating the characteristics of seawater quality centered about eutrophication in Mokpo harbour. By applying the OECD standards of trophic classification to the parameters such as secchi depth, total inorganic nitrogen, phosphate phosphorus and chlorophyll-a, the trophic level of seawater in Mokpo harbour was evaluated to be in eutrophic state in summer. The estimation of pollution index by eutrophication showed the seawater quality of Mokpo harbour to deteriorate and fall under the regular grades. The results of eutrophic index estimation showed the high otentiality of red tide occurrence in Mokpo harbour.

석탄계 핏치의 열처리 온도 및 압력에 따른 결정화도와 기공도 그리고 산화저항성 등을 관찰하였으며, hexagonal type 4D 탄소/탄소 복합재를 석탄계 핏치로 가압함침 및 탄화시킨 다음 가해준 압력이 고밀도화에 미치는 영향을 관찰하였다. 석탄계 핏치의 가압탄화 압력이 흑연화도에 크게 영향을 미치지 않았으며, 기공면적비에 있어서는 압력을 600bar로 상승시켜 줌으로써 상압 처리한 경우 보다 1.5배 정도 감소 하였다. 650˚C까지 열처리하여 얻은 코우크스의 산화반응 개시온도는 처리압력이 증가함에 따라서 지연되었다. 탄소/탄소 복합재의 함침압력을 100bar에서 600bar로 상승시켜 줄 경우 밀도 증가율이 크게 향상 되었으며 기공도는 감소하였다.

The in situ observations and the seawater analyses were conducted in July and August, 1996 for the purpose of describing the characteristics of organic pollution, dissolved oxygen distributions, and the evaluation of water quality in Mokpo harbour. The vertical density distribution of water column was found to be in stable structure with higher water temperature and lower salinity on surface layer at ebb tide in summer. In July, dissolved oxygen was shown to be oversaturated on surface and bottom layers, while in August, which was shown to be oversaturated on surface layer, and to be unsaturated on bottom layer as 68∼93% of saturation percentage. Dissolved oxygen of bottom layer in August was evaluated to be under the regular grades, based on Korean standards of seawater quality. In view of COD, the seawater quality of Mokpo harbour in summer was evaluated to be deteriorated due to organic wastes and graded to be the third class, and TSS of Mokpo harbour in summer was graded to be the second class, based on Korean standards of seawater quality. In particular, COD of surface layer in August was found to be under the regular grades. It is, therefore, necessary to take measures for the control of pollution loads and the proper management of seawater quality in Mokpo harbour. The distribution patterns of DO, COD, VSS and Chlorophyll-a on surface layer along the downstream center line from inner harbour to harbour entrance were similar to one another at ebb tide in August.

the observations in situ and the seawater analyses were conducted in July and August, 1996 for the purpose of evaluating the characteristics of seawater quality centered on eutrophication in Mokpo harbour. By applying the OECD standards of trophic classification to the parameters such as secchi depth, total inorganic nitrogen, phosphate phosphorus and chlorophyll-a, the trophic level of seawater in Mokpo harbour was evaluated to be in eutrophic state in summer. By the estimation of pollution index with relation to eutrophication, the seawater quality of Mokpo harbour was evaluated to be under the regular grades and this evaluation was found to be different from the results of evaluation obtained by the environmental index of single parameter, chemical oxygen demand. By the estimation of eutrophication index, the seawaters of Mokpo harbour were shown to have the high potentiality of red tide occurrence.