• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.7 no.1
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• pp.9-27
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• 1971

Oceanography of the Subarctic North Pacific Ocean is reviewed. The submarine topography and the current systems in the region are explained. Recent serial observation data reveals that. though the upper mixed layer of low salinity is relatively thick. the pattern of the property distribution in winter is essencially similar to that in summer. Alaskan Stream Extension Water. which influences the abundance and the location of demersal fishes. extends northward to 58${\circ}$ N Lat in the Bering Sea. A southeastward intrusion of the Bering Borcal Cold Water causes the formation of a sharp oceanic front. where the demersal fishes such as Alaska pollacks and cods arc concentrated. The Alaska pollacks seem to avoid the low salinity water of the Alaskan Coastal Water.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.7 no.1
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• pp.8-8
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• 1971

Oceanography of the Subarctic North Pacific Ocean is reviewed. The submarine topography and the current systems in the region are explained. Recent serial observation data reveals that. though the upper mixed layer of low salinity is relatively thick. the pattern of the property distribution in winter is essencially similar to that in summer. Alaskan Stream Extension Water. which influences the abundance and the location of demersal fishes. extends northward to 58${\circ}$ N Lat in the Bering Sea. A southeastward intrusion of the Bering Borcal Cold Water causes the formation of a sharp oceanic front. where the demersal fishes such as Alaska pollacks and cods arc concentrated. The Alaska pollacks seem to avoid the low salinity water of the Alaskan Coastal Water.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.05a
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• pp.1-6
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• 2002

The study offer a suggestion that from result in being a case to efflorescence for decrease a plan: $\circled1$ A efflorescence of concreat a structure will be the prograss plan; In the materials, depress use to the water-sand in the construction, admonish unification of front and rear in the environment, consideration requisite concreat don't the occurrence efflorescence. $\circled2$ Ma sonry building efflorescence establish a ventilation opening and a waterway to ma sonry the times avoid the winter or the rainy season. Ma sonry building efflorescence will be make good among a brick to a brick interval closely mortar. $\circled3$ Tile building, tile of plasticity temperature is appropriate, reduce the deviation, parapet part of efflorescence will be make good closely mortar. A construction material part a meterial developing need Perfection of construction a efflorescence occurrence is the minimum, a plan Part developed so on, composition of a ommection field systematic effort need a efflorescence Prevention a kind of detail.

• Journal of the Korean earth science society
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• v.22 no.5
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• pp.423-426
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• 2001

The accretion disk with viscosity including collisions is examined. The diffusion process are also considered for a given mass distribution in the disk. Under such a circumstance the diffusion coefficient is simply proportional to 1/${\sqrt{r}}$ The disk rapidly transfers the turbulent angular momentum and the wave front toward the outer cold regions. Then an instability situation occurs in the disk.

• Fisheries and Aquatic Sciences
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• v.3 no.1
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• pp.8-13
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• 2000

Monthly mean chlorophyll concentration in the East Sea was estimated from the ocean color observed by the Coastal Zone Color Scanner (CZCS) on Nimbus-7 satellite which had performed various remote sensing missions from 1979 to 1986. The areas of high chlorophyll concentration were found in the sea between Siberia coast and Sakhalin Island, in the Donghan Bay and in the Ulleung Basin. In the southwestern East Sea, especially in the area near Ulleung Island, the yearly maximum chlorophyll concentration occurred in December. The chlorophyll concentration in Ulleung Basin in December was about two times higher than during spring bloom in April. The early winter bloom occurred in the warm side of the front that was formed between warm water from the East China Sea and nutrition rich cold water from the northern East Sea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.3
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• pp.185-192
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• 1991

The vertical distribution and chemical characteristics of water masses were measured along two south-north transects in the polar front region of the central Korean East Sea. In February, a thermocline was present at depth between 50m and loom at the southern sites of a landward A-transect, and its depth was gradually deepened northward. At an outside B-transect, a thermocline was observed at significantly deep depth of 300m to 400m at two northern stations(Stn. 10 and 11), though the depth of the southward stations was nearly identical to that at the northward stations on a A-transect. In September, there were vertically more various water masses, i.e. the Tsushima Warm surface water(TWSW) or more than $20^{\circ}C$, the Tsushima Middle water(TMW) with a range of $12{\~}17^{\circ}C$, the North Korea Cold Water(NKCW) with $1{\~}7^{\circ}C$ temperature, the Japan Sea Proper Water(JSPW) of less than $1^{\circ}C$, and the mixed water. The North Korea Cold Water could be distinguishable from the other waters, especially from the mixed water of the Tsushima Middle Water and the Japan Sea Proper Water by the pattern of $T-O_2$ diagram. For instance, the North Korea Cold Water had higher oxygen by $1{\~}2ml/l$ than those in the mixed water, although both the two water masses ranged $1{\~}7^{\circ}C$ in water temperature. AOU value was the highest in the JSPW and the lowest in the TWSW. Also, AOU indicated a nearly linear and negative correlation with water temperature. However, AOU data for two masses, the NKCW and the TMW, in September departed remarkably from a regression line. Moreover, the ratio of $$\Delta P/\Delta AOU)$ in September was about $0.45{\mu}g-at/ml$ and higher than the value observed in the open sea. This high value could be elucidated by two factors; intrusion of the NKCW with high oxygen and molecular diffusion of dissolved oxygen from the surface into the lower layer. AOU would be a useful tracer for water masses in the polar front area of the Korean East Sea.

• Journal of the Korean earth science society
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• v.24 no.4
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• pp.303-314
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• 2003

Ocean-air observation using an Automatic Weather Station (AWS) and Conductivity Temperature Depth (CTD) was conducted in the Mid-Yellow Sea off Korea during 8-10 July 2002. A water mass lower than 17$^{\circ}C$ around the Taean peninsula and a tidal front between 36$^{\circ}$20'N and 36$^{\circ}$30'N were observed. The horizontal distribution of air temperature was similar to that of sea surface temperature (SST). Hourly observation around Dukjuk island showed the cold and saline southwesterly and the warm and fresh northeasterly in phase with tidal current. Sea fogs two times formed at 2300 LST 8-0130 LST 9, and 0300-0600 LST 9 July 2002 during the observation period, respectively. During the initial stage of fogs, winds became northeasterly at the speed of 2-4m/s$^{-1}$, and air temperature dropped to 18$^{\circ}C$, as the North Pacific High weakened. The satellite image indicated that sea fogs formed over warm water in the western Yellow Sea and moved eastward toward the observation site, which could be called a steam fog. The fogs dissipated when wind speed and air temperature increased.

• 한국해양학회지
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• v.15 no.1
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• pp.17-33
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• 1980

The materials were obtained in the eastern Gulf of Alaska and the south- eastern Bering Sea during the cruise of the research vessel, Ohdae San, from July to October 1978. A total of 76 samples were taken by NORPAC net from a depth of 200 meters or less in coastal areas. 1. The surface water temperature in the coastal waters, varing from 9 to 10$^{\circ}C$, was lower than that in offshore waters which varied from 10 to 12.9$^{\circ}C$ in the eastern Gulf of Alaska. Thermocline was formed in the 30∼50 meter layer. Salinity of the coastal waters of Kenai Peninsula and Kodiak was 30 which was slightly lower than that of offshore. 2. The water temperature of the surface layer down to 30 meters varied from 7 to 10$^{\circ}C$ and from 1 to 9$^{\circ}C$ in the layer below 30 meters in the south-eastern Bering Sea. Meandering thermal front spread from the Alaska Peninsula to St. Matthew Island by way of St. Paul, and a thermocline was found at the 30∼50 meter layer Salinity ranged from 31.0 to 33.0 and that of northern and coastal waters was little lower than that of offshore. 3. Zooplankton biomass fluctuated from 0.1 to 23.6cc/10㎥ in the eastern Gulf of Alaska and 2.0 to 26.1cc/10㎥ in the south-eastern Bering Sea. Plankton was rich in the following areas, the inshore Kodiak waters, the northern Bering Sea, the Coastal waters and waters adjacent to Alutian islands however, poor in the central Bering Sea. In general, the south-eastern Bering Sea has a higher concentration of plankton volume than the eastern Gulf of Alaska. 4. Twenty three species representing 17 genera of copepods were identified from the samples. These were mostly composed of the cold water species, such as Pseudocalanus minutus, Acartia longiremis, Metridia lucens and Eucalanus bungii var. bungii. 5. The cold oceanic species were composed of Calanus cristatus, C.plumchrus, Metridia lucens, Eucalanus bungii var. bungii and Scolecithricella minor. The cold neritic species were Centropages abdominalis, Pseudocalanus minutus, Acartia longiremis, Eurytemora herdmanii, Pontella pulvinata, P. longipedata and Tortanus discaudatus. On the other hand, the warm oceanic species were Calanus tenuicornis and Oithona plumifera. The cosmopolitan species were Calanus finmarchicus and Oithona similis. 6. It was suggested that the cold oceanic species, Eucalanus bungii var. bungii and Metridia lucens in the south-eastern Bering Sea can be recommended as a valuable indicator species for finding the fishing grounds of demersal fish such as pollock and yellowfin sole in this area.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.130.1-130.1
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• 2010

미국과 유럽에서는 이미 10여 년 전부터 250MW급 이상의 대용량 석탄IGCC 플랜트를 상업운전 하고 있으며, 일본과 중국을 비롯한 아시아에서도 대용량 플랜트를 시운전하고 있거나 건설 중에 있다. 한국에서는 제4차 전력수급계획에 의거 태안화력 부지 내에 300MW급 IGCC 플랜트 건설을 추진 중이며, 두산중공업은 '10년 상반기에 IGCC 가스화 플랜트에 대한 FEED 설계 (Front-Eng Engineering Design)를 완료하였다. 그 과정 중 설계조건에 의한 기본 엔지니어링 사항과 석탄 가스화 플랜트에 대한 성능예측 결과를 본 연구에서 소개한다. 가스화 플랜트의 엔지니어링은 가스화 블록과 가스정제 블록으로 구분하여 수행하였다. Process Data를 이용하여 PFD Development, P&ID Generation, Equipment Specification 개발, HAZOP 수행, Architecture Engineering 등의 순으로 FEED 설계를 진행하였다. BOD (Basis of Design)를 기준으로 운전조건별 Heat & Mass Balance와 Process Flow를 재검토하고 각 기기별 운전개념을 반영하여 P&ID를 개발하였다. 그리고 배관, 전기 및 제어에 대한 각종 Diagram 개발과 HSE (Health, Safety and Environment) 관련 설계를 수행하였다. IGCC 1호기의 엔지니어링 수행과 함께 Next 호기 자체설계 역량 확보를 위해 두산중공업은 'DIGITs'로 명명된 개념기본설계 Tool을 개발하고 있다. DIGITs는 공정모델링, 단위기기 개념설계, 공정구성 (Process Configuration) 및 종합 Database Package 형태로 구성된다. DIGITs에 의한 계산 결과 공정사 Process Data 기준시 가스화 블록 출구에서 Syngas HHV와 Syngas 현열은 각각 약 $636MW_{th}$와 약 $18MW_{th}$로, Plant 설계조건 $630MW_{th}$를 만족하는 것으로 예측되었다. 향후 DIGITs는 가스정제 블록 및 주변 BOP 설비 등과 연계한 종합 개념기본설계 Tool로써 개발 진행 중이다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.610-615
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• 2016

Diverse accessories are used in automobiles, such as navigation systems, front and rear cameras, spoilers, and sun visors. Sun visors block sunlight so that drivers can drive safely with a better view, and they are used in many automobile designs. However, when large plastic products are manufactured using injection molding, there are many difficulties that develop, like weld lines, short shots, flow marks, imperfections, and distortion. In this study, a CAE simulation was conducted based on previous results to predict potential problems in the injection molding of large products. The flow characteristics up to complete charge for the melting resins were captured using a computer-aided engineering simulation. The temperature departure on the front part of a flow was about $10^{\circ}C$ and very stable. The practical ejecting time of the cold runner was about 70 seconds in the simulation. Finally, the capability of a suitable injection machine was calculated and recommended by prediction of the injection pressure and the die clamping force.