• Title/Summary/Keyword: Sea-and-air

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Relationship between Sea Surface Temperature and Air Temperature Variation Depend on Time Scale at Coastal Stations in Korea (시간스케일에 따른 해양표면수온과 기온의 변동 및 상관연구)

  • 장이현;강용균;서영상
    • Journal of Environmental Science International
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    • v.9 no.4
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    • pp.303-309
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    • 2000
  • The relationship between air temperature and sea surface temperature and studied using the daily air temperature and sea surface temperature data for 25 years (1970~1994) at 9 coastal stations in Korea. Seasonal variations of air temperature have larger amplitudes than those of sea surface temperature. The seasonal variations of air temperature leads those of sea surface temperature by 2 to 3 weeks. The anomalies of sea surface temperature and air temperature with time scales more than 1 month are more ghighly correlated than those of short term, with time scales less than 1 month. Accumulated monthly anomalies of sea surface temperature and air temperature for 6 months shwoed higher correlation than the anomailes of each month. The magnitudes of sea surface temperature and air temperature anomalies are related with the duration of anomalies. Their magnitudes are large when the durations of anomalies are long.

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The Prospect of the Development of Sea&Air Transportation Routes around the Yellow Sea Regions (환황해권 Sea&Air 수송의 발전 가능성 전망)

  • Kim, Tae-Seung;Won, Dong-Woo;Yun, Jung-Won
    • Journal of Korea Port Economic Association
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    • v.22 no.3
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    • pp.189-207
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    • 2006
  • As the development of Northeast Asian logistics hub becomes one of the national agenda for further development, the sea&Air transport around the Yellow Sea regions has drawn attention of many scholars and government officials. The Sea&air transport is a mode of transportation combining the advantage of high-speed in air transport with the advantage of low-price in sea transport. Hence the sea&air aims at a niche market between air and sea. This paper reviews the possibility of development of the sea&air transport in the aspects of competitiveness over other modes, future demand condition, and the change of the technology and transport environment. The result is that the sea&air is competitive in the aspect of time as well as cost, and sustainable in the aspect of future demand condition. But, it is not stable in the aspect of the conditions of technology or transport demand. Especially, the progress of air transport technology which is aiming at the door-to-door transport among mid- and small- cities, and the rapidly increasing strategic alliances of international airlines with Chinese airlines for the market of China will undermine the stability of the sea&air transport seriously As alternatives, this paper proposes the 3-stage development strategy of sea&air transport. First, at the stage of transshipement, the development of high speed vessels to reduce the time crossing the Yellow Sea and the proactive marketing strategy to induce Chinese-owned products should be emphasized. Second, the value added logistics activity which will secure the demand of the sea&air transport should be developed. Third, demand creation by developing the SCM hub in Incheon is final goal for the logistics hub strategy as well as the sea&air transport.

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The Influences of Sea Breeze on Air Pollution Concentration in Pusan, Korea (해풍이 부산 지역의 대기 오염 농도에 미치는 영향)

  • Jeon, Byeong-Il;Kim, Yu-Geun;Lee, Hwa-Un
    • Journal of Environmental Science International
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    • v.3 no.4
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    • pp.357-365
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    • 1994
  • Air pollution characteristics and the influence of sea breeze on air pollution concentration were studied using the data measured at 7 air quality continuous monitoring stations in Pusan, 1993. Maximum air pollution concentration in Pusan was Gamjeondong for $SO_2$, Sinpyeongdong for TSP, Daeyeondong for $O_3, Kwangbokdong for $NO_2$, Beomcheondong for CO and all substances were under annual ambient air quality standards. Increased rate of concentration for sea breeze was 24.4% for 502, 31.5% for TSP, 8.0% fort $O_3, 26.7% for $NO_2$, 15.7% for CO. Frequencies distribution of $SO_2$, TSP, $O_3$, $NO_2$, and CO concentration for sea breeze moved toward high concentration class.

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Daily Mean Sea Level and Atmospheric Pressure Along the Coasts of the Northwestern Pacific Ocean

  • Oh, Im-Sang;Moon, Il-Ju;Youn, Yong-Hoon
    • Journal of the korean society of oceanography
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    • v.32 no.4
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    • pp.171-180
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    • 1997
  • Daily mean sea level variability and its response to atmospheric pressure along the coasts of the northwestern Pacific Ocean are investigated. Daily values of sea level and atmospheric pressure covering the period 1976-1986 from 72 stations are analyzed. The sea level and the air pressure in all the data set have a definite seasonal signal, and higher frequency oscillations at time scales of several days to several weeks are also observed. Among the short-period oscillations of sea level with periods shorter than six months, the period of around 3 or 4 months is dominant in most study stations. According to the statistical analysis of sea level and air pressure, the length scale of sea level variability is smaller than that of air pressure for the present study area. The overall variability of sea level is found to be the smallest around Hokkaido, Japan and the largest in the China coasts. Large short-period (< 6 months) sea level variability is found in the southern coasts of China and Hokkaido, and large long-period (> 6 months) variability in the southern coasts of Japan and Korea along Tsushima Current and Kuroshio. The patterns of air pressure are very similar to those of sea level. The air pressure field is found to account for 31% of the overall sea level variability in the study area. Conside.ins the fact that the results (40%) of Pang and Oh (1995) were obtained through monthly sea level, the present result implies that the short-period sea level variability is less affected by air pressure. Generally the sea level response to air pressure are found to be isostatic, but significantly nonisostatic for the periods around 4 months and for those of 2 to 4 days. In particular, nonisostatic response for higher frequencies seem to be due to the restrictions to water transport necessary for barometric responsein the Korea Strait.

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Estimation of the Effective Region of Sea/Land Breeze in West Coast Using Numerical Modeling (수치모델링을 이용한 서해안 지역에서의 해륙풍 영향권 산정에 관한 연구)

  • Jeong, Ji-Won;Lee, Im-Hack;Lee, Hee-Kwan
    • Journal of Korean Society for Atmospheric Environment
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    • v.24 no.2
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    • pp.259-270
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    • 2008
  • The regional air movement in a coastal area is generated by the different heat capacities of sea and land sides, which is called sea/land breeze. In the west coast area, the local air quality is significantly influenced by this sea/land breeze. In this study, the mathematical model is proposed to estimate the effective area of sea/land breeze. A commercial air model, that is suggested as an alternative air model by USEPA, is introduced to simulate the mechanism of sea/land breeze generation. From this study, it is confirmed that the numerical approach proposed in this study is reliable to predict the effective area of sea breeze in a coastal area. It implies that the current application of common air model needs to be carefully reviewed especially when dealing with a coastal air quality issue. It is also found that the sea breeze in Incheon area has the impact in the range of approximately 24 km in-land side, so-called penetration length.

Estimation of the air temperature over the sea using the satellite data

  • Kwon B. H.;Hong G. M.;Kim Y. S.
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.392-393
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    • 2005
  • Due to the temporal and spatial simultaneity and the high-frequency repetition, the data set retrieved from the satellite observation is considered to be the most desirable ones for the study of air-sea interaction. With rapidly developing sensor technology, satellite-retrieved data has experienced improvement in the accuracy and the number of parameters. Nevertheless, since it is still impossible to directly measure the heat fluxes between air and sea, the bulk method is an exclusive way for the evaluation of the heat fluxes at the sea surface. It was noted that the large deviation of air temperature in the winter season by the linear regression despite good correlation coefficients. We propose a new algorithm based on the Fourier series with which the SST and the air temperature. We found that the mean of air temperature is a function of the mean of SST with the monthly gradient of SST inferred from the latitudinal variation of SST and the spectral energy of air temperature is related linearly to that of SST. An algorithm to obtain the air temperature over the sea was completed with a proper analysis on the relation between of air temperature and of SST. This algorithm was examined by buoy data and therefore the air temperature over the sea can be retrieved based on just satellite data.

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Comparison of Recovery Rate and Fatty Acid Composition of Dried Sea Cucumbers Apostichopus japonicus Dried by Hybrid Heat Pump Decompression and by Hot Air (2종류의 건조기로 제조한 돌기해삼(Apostichopus japonicus)의 복원율과 지방산조성 비교)

  • Jeong, U-Cheol;Jin, Feng;Anisuzzaman, Md;Choi, Byeong-Dae;Jung, Hyun-Chol;Lee, Sang-Ro;Kang, Seok-Joong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.52 no.3
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    • pp.232-240
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    • 2019
  • Approximately 80% of the world's sea cucumbers Apostichopus japonicas are processed into dried sea cucumbers. The hot air-drying method is currently used in industry, but it has many problems, such as a short drying time, severe browning, high nutrition loss, and low recovery. In this study, the moisture absorption rate, dry recovery rate, and lipid nutrient composition of sea cucumber dried by heat pump decompression and with a hybrid dryer were investigated. The moisture absorption rates for hybrid-dried sea cucumbers at 24, 48, 72, 96, and 120 h were 241.3%, 427.7%, 652.0%, 721.0%, and 742.2%, respectively. The moisture absorption rates for hot air-dried sea cucumbers were 155.8%, 240.0%, 390.3%, 655.5%, and 667.4%, respectively. Thus, moisture absorption was faster and greater with hybrid drying than with hot air drying. The dry recovery rate at 24 h was greater for hybrid-dried sea cucumber (70.7%) than for hot air-dried sea cucumber (59.8%). Saturated fatty acid contents of the hybrid- and hot air-dried sea cucumbers were 30.0% and 37.5%, respectively. Moreover, greater ${\Sigma}n-3$ polyunsaturated fatty acid content was found in hybrid-dried sea cucumber (15.8%) than in hot air-dried sea cucumber (11.7%).

On large-scale Air Pollution in the Yellow Sea Region: Satellite and Ground Measurements

  • Y. S. Chung;Kim, H. S.;Kim, Y. S.
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.E2
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    • pp.83-88
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    • 2003
  • The present study details air pollution measurements in the Yellow Sea of East Asia. Large-scale air pollution was observed through satellite images and ground monitors in Chongju-Chongwon of central Korea. Evidence of a duststorm transport and resulting dustfall from the Gobi Desert in north China and Mongolia is shown. Also, transport of anthropogenic air pollutants from China to the Yellow Sea, Korea, and Japan was detected and discussed. It was found that the level of air pollution concentrations at a regional back-ground site increased 2 ∼ 4 times than the values observed with the relatively clean air, when massive air pollution from China moved to the Korean Peninsula. Satellite measurements will be useful for monitoring regional- and global-scale air pollution in the future.

Forecasting and Suggesting the Activation Strategies for Sea & Air Transportation between Korea and China (한·중 간 Sea & Air 물동량 전망 및 활성화 방안에 관한 연구)

  • Jung, Hyun-Jae;Jeon, Jun-Woo;Yeo, Gi-Tae;Yang, Chang-Ho
    • Journal of Navigation and Port Research
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    • v.36 no.10
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    • pp.905-910
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    • 2012
  • In early 1990s, the Sea & Air Transport Cargoes (SATC) was increased annually with more than 50% rate due to the rising trade between Korea and China. However, after that, the increasing rate of the SATC was slowdown from the late 1990s, furthermore, recently it became sluggish and declined. This phenomenon is totally different compared to the skyrocketing trade volumes between two countries. In this respect, to forecast the SATC, draw out the factors for activation, and calculate the weight of priority of these factors are urgently needed. To achieve the research objectives, the ARIMA and Fuzzy-AHP were used as research methodology. The estimated volume of SATC using the data from year 2007 to 2012 on the ARIMA model, will be reached approximately 33,000 tons in year 2015. In the mean time, For drawing out and weighing the activation factors for SATC, the Fuzzy-AHP was adopted. As a result, 'Sea & Air transportation-related information system policies' is the most important factor among the principle criteria, and 'the construction of consolidation logistics center' is the most important factor among the 12 sub-principle criteria.

A Study on Concatenation of Air & Sea Logistics' Information Using Telematics System;Case of Inchoen u-City (텔레매틱스 시스템을 이용한 항공 및 항만 물류 정보 연계에 관한 연구;인천 첨단물류도시 대상)

  • Hong, Seung-Beom;Kim, Woong-Yi
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.15 no.4
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    • pp.100-107
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    • 2007
  • We proposed the concatenation of logistics' Information to constructing the intelligent logistics city that is to manage efficiently cargo distribution as providing at real-time information of cargo location trace and management through the Telematics/RFID. Case of the Incheon of the "Air Logistics Hub", this area is on an increasing trend on the quantity of cargo transport of the Air & Sea cargo system until 2006. As intelligent project of the Air's and the Sea's field is independently developed at each area, it is a problem on the concatenation of logistics' information such as freight location trace and management, operation management and route information of cargo vehicles. Therefore, we propose the advanced transport service model for the concatenating smoothly of Air & Sea cargo system. In this paper, we only manage the model of Air & Sea cargo system of the advance logistics city.

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