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Predicting the Effects of Rooftop Greening and Evaluating CO2 Sequestration in Urban Heat Island Areas Using Satellite Imagery and Machine Learning (위성영상과 머신러닝 활용 도시열섬 지역 옥상녹화 효과 예측과 이산화탄소 흡수량 평가)

  • Minju Kim;Jeong U Park;Juhyeon Park;Jisoo Park;Chang-Uk Hyun
    • Korean Journal of Remote Sensing
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    • v.39 no.5_1
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    • pp.481-493
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    • 2023
  • In high-density urban areas, the urban heat island effect increases urban temperatures, leading to negative impacts such as worsened air pollution, increased cooling energy consumption, and increased greenhouse gas emissions. In urban environments where it is difficult to secure additional green spaces, rooftop greening is an efficient greenhouse gas reduction strategy. In this study, we not only analyzed the current status of the urban heat island effect but also utilized high-resolution satellite data and spatial information to estimate the available rooftop greening area within the study area. We evaluated the mitigation effect of the urban heat island phenomenon and carbon sequestration capacity through temperature predictions resulting from rooftop greening. To achieve this, we utilized WorldView-2 satellite data to classify land cover in the urban heat island areas of Busan city. We developed a prediction model for temperature changes before and after rooftop greening using machine learning techniques. To assess the degree of urban heat island mitigation due to changes in rooftop greening areas, we constructed a temperature change prediction model with temperature as the dependent variable using the random forest technique. In this process, we built a multiple regression model to derive high-resolution land surface temperatures for training data using Google Earth Engine, combining Landsat-8 and Sentinel-2 satellite data. Additionally, we evaluated carbon sequestration based on rooftop greening areas using a carbon absorption capacity per plant. The results of this study suggest that the developed satellite-based urban heat island assessment and temperature change prediction technology using Random Forest models can be applied to urban heat island-vulnerable areas with potential for expansion.

Estimation of Chlorophyll-a Concentration in Nakdong River Using Machine Learning-Based Satellite Data and Water Quality, Hydrological, and Meteorological Factors (머신러닝 기반 위성영상과 수질·수문·기상 인자를 활용한 낙동강의 Chlorophyll-a 농도 추정)

  • Soryeon Park;Sanghun Son;Jaegu Bae;Doi Lee;Dongju Seo;Jinsoo Kim
    • Korean Journal of Remote Sensing
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    • v.39 no.5_1
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    • pp.655-667
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    • 2023
  • Algal bloom outbreaks are frequently reported around the world, and serious water pollution problems arise every year in Korea. It is necessary to protect the aquatic ecosystem through continuous management and rapid response. Many studies using satellite images are being conducted to estimate the concentration of chlorophyll-a (Chl-a), an indicator of algal bloom occurrence. However, machine learning models have recently been used because it is difficult to accurately calculate Chl-a due to the spectral characteristics and atmospheric correction errors that change depending on the water system. It is necessary to consider the factors affecting algal bloom as well as the satellite spectral index. Therefore, this study constructed a dataset by considering water quality, hydrological and meteorological factors, and sentinel-2 images in combination. Representative ensemble models random forest and extreme gradient boosting (XGBoost) were used to predict the concentration of Chl-a in eight weirs located on the Nakdong river over the past five years. R-squared score (R2), root mean square errors (RMSE), and mean absolute errors (MAE) were used as model evaluation indicators, and it was confirmed that R2 of XGBoost was 0.80, RMSE was 6.612, and MAE was 4.457. Shapley additive expansion analysis showed that water quality factors, suspended solids, biochemical oxygen demand, dissolved oxygen, and the band ratio using red edge bands were of high importance in both models. Various input data were confirmed to help improve model performance, and it seems that it can be applied to domestic and international algal bloom detection.

A Study on Predicting the Logistics Demand of Inland Ports on the Yangtze River (장강 내수로 항만의 물류 수요 예측에 관한 연구)

  • Zhen Wu;Hyun-Chung Kim
    • Korea Trade Review
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    • v.48 no.3
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    • pp.217-242
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    • 2023
  • This study aims to analyze the factors influencing the logistics demand of inland ports along the Yangtze River and predict future port logistics demand based on these factors. The logistics demand prediction using system dynamics techniques was conducted for a total of six ports, including Chongqing and Yibin ports in the upper reaches, Jingzhou and Wuhan ports in the middle reaches, and Nanjing and Suzhou ports in the lower reaches of the Yangtze River. The logistics demand for all ports showed an increasing trend in the mid-term prediction until 2026. The logistics demand of Chongqing port was mainly influenced by the scale of the hinterland economy, while Yibin port appeared to heavily rely on the level of port automation. In the case of the upper and middle reach ports, logistics demand increased as the energy consumption of the hinterland increased and the air pollution situation worsened. The logistics demand of the middle reach ports was greatly influenced by the hinterland infrastructure, while the lower reach ports were sensitive to changes in the urban construction area. According to the sensitivity analysis, the logistics demand of ports relying on large cities was relatively stable against the increase and decrease of influential factors, while ports with smaller hinterland city scales reacted sensitively to changes in influential factors. Therefore, a strategy should be established to strengthen policy support for Chongqing port as the core port of the upper Yangtze River and have surrounding ports play a supporting role for Chongqing port. The upper reach ports need to play a supporting role for Chongqing port and consider measures to enhance connections with middle and lower reach ports and promote the port industry. The development strategy for inland ports along the Yangtze River suggests the establishment of direct routes and expansion of the transportation network for South Korean ports and stakeholders. It can suggest expanding the hinterland network and building an efficient transportation system linked with the logistics hub. Through cooperation, logistics efficiency can be enhanced in both regions, which will contribute to strengthening the international position and competitiveness of each port.

A Study on the Transitions and Site of temporary palace(Onyanghaenggung) according to the <Oncheonhaenggungdo>(1795) (<온천행궁도(溫泉行宮圖)>(1795)의 온양행궁지 추정 및 온양행궁 변천 고찰)

  • LEE Jeongsoo;KIM Ilhwan;LEE Kyeongmi;JI Wonku;CHOI Jaeseong
    • Korean Journal of Heritage: History & Science
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    • v.56 no.4
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    • pp.94-108
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    • 2023
  • Onyanghaenggung Palace(temporary palace at Onyang) is an important cultural heritage that can substantially confirm the king's onhaeng(溫行) base on literature records such as <Ongungyeonggoedae(溫宮靈槐臺)>, <Oncheonhaenggungdo(溫泉行宮圖)> of 『Ongungsasil(溫宮事實)』『, Younggoedaegi(靈槐臺記)』and cultural property such as Yeonggoedae(靈槐臺) and Shinjeong Monument(神井碑). As the Onyang Tourist Hotel is located in the presumed site of the Onyanghaenggung Palace, even the identity of the Onyanghaenggung Palace site is being threatened without restoration efforts. The purpose of this study is to estimate the location of Onyanghaenggung Palace based on <Oncheonhaenggungdo> before the damages during the Japanese colonial period. To achieve these purposes, records related to Onhaeng during successive kings' terms in the Joseon Dynasty are first reviewed, before changes in the architecture of Onyanghaenggung Palace that took place in the Joseon Dynasty and damage suffered during the Japanese colonial period are summarized, and finally <Oncheonhaenggungdo>, <Eupji>, <Ancient Maps>, <Jijeokwondo> are reviewed. Based on these processes, the location of Onyanghaenggung Palace is estimated by comparing the current Onyang Tourist Hotel and the surrounding area. The results of this study are as follows. First, if the 1,758 cheok(尺) of 「Onyanggun eupji」 and 「Hoseo eupji」 are converted in Jucheok(周尺), the scope of Onyanghaenggung Palace is close to the inner circumference of the site(垈) in Jijeokwondo(1914). Second, the streamlet leading to Oncheoncheon(溫泉川) from the southern side of Onyanggwan(溫陽館), the hot spring hole in use of <Distribution Map of Hot Spring(溫泉分布見取圖)>(1925, 1928), and considering the relationship of the inner east gate(內東門), Bigak(碑閣), Sinjeong(神井) of <Oncheonhaenggungdo>, the building of Hermann Gustav Theodor Sander and the Copyright Commission's Onyang Hot Springs photograph can be estimated as the Onyanghaenggung Palace Hot-spring, namely Tangsil(湯室). Third, in the process of developing to amusement park, the transfer and relocation of the Yeonggaedae site(a governmentowned property) was requested by Gyeongnam Railway Company, but Chungcheongnam-do denied transfer and relocation of the Yeonggaedae because of the importance in the history of Onyang Hot Springs, so the government-owned Yeonggaedae Monument site were permanently preserved at the current location together with the hoe tree(Sophora japonica L.). Also, Yeonggoedae in <Tourists Attractions around Gyeongnam Railway in Joseon (朝鮮京南鐵道沿線名所交通図絵)> (1929) is shown to exist in its current location, and it can be seen that the Shinjeong Monument Pavilion was moved to the front of Shinjeonggwan (神井館). Based on the circumference of Onyanghaenggung Palace, the location of Onyanghaenggung Palace Hot Spring (Tangsil) and Yeonggaedae Monument Pavilion, changes in roads and lots of land during the Japanese colonial period and the modern period, as well as the location of Onyanghaenggung Palace and other major buildings, can be estimated to extend to the current Shimin-ro and Onyang Hot Spring Market.

A Study on Factors Affecting ESG Management Intentions of Small and Medium Enterprises : Focusing on the Mediating Effect of Attitude and the Moderating Effect of Employees' Innovation Resistance (중소기업 ESG 경영 도입의도에 영향을 미치는 요인 : 태도의 매개효과 및 종업원 혁신저항성의 조절효과)

  • Lee, Yun-hyo;Park, Koung-hi;Chung, Byoung-gyu
    • Journal of Venture Innovation
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    • v.6 no.2
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    • pp.41-65
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    • 2023
  • This study was conducted to empirically analyse the factors that influence SMEs' intention to adopt ESG. For this purpose, we first derived the variables of usefulness of ESG and ease of adoption. In addition, we adopted CEO's will because of the importance of CEO's role in decision-making in SMEs. In addition, we added customer's request, government support, and credit evaluation reflection as institutional factors for ESG management. To examine the mediating role of attitudes and employees' innovation resistance in these relationships and how they affect ESG adoption, we set up a research model. These factors were used in the empirical analysis with 368 valid responses from the survey. Hierarchical regression analysis method using SPSS 24.0 was used for statistical analysis, and Process Macro 4.0 based on SPSS 24 was used for mediation and moderation effects. The results of the empirical analysis of this study showed that the usefulness of ESG adoption, ease of adoption, CEO's will, customer's request, government support, and credit evaluation reflection all had a positive and significant effect on the intention to adopt ESG management. In particular, among the variables affecting ESG adoption, CEO's will was found to be the most influential. Attitudes were also found to play a mediating role between the influencing factors and intention to adopt ESG management, as well as the mediating effect of employee' innovation resistance. The academic implications of this study include the identification and empirical testing of each of the influencing variables of ESG management adoption in the scarce literature on ESG in SMEs, and the prioritisation of the influence of these factors on adoption intention, which can be used to promote the adoption of ESG management. In terms of practical implications, it is important for SMEs to have a win-win relationship with large corporations, an ecosystem such as government support, in order to improve CEO awareness and motivate the CEO's will, and for smooth introduction of ESG management, it is necessary to find ways to reduce resistance through sufficient communication with organizational members to make them aware of the need.

Effects of Increasing Air Temperatures and CO2 Concentrations on Herbicide Efficacy of Acalypha australis and Phytotoxicity of Soybean Crops (대기온도와 CO2 농도 증가에 따른 우점잡초 깨풀의 제초제 약효 및 콩 약해 변화)

  • Hyo-Jin Lee;Hyun-Hwa Park;Ye-Geon Kim;Do-Jin Lee;Yong-In Kuk
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.68 no.3
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    • pp.121-133
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    • 2023
  • The purpose of this study was to improve weed management systems under varying carbon dioxide concentrations and temperatures by evaluating the growth of Acalypha australis and observing the efficacy of four foliar and four soil herbicides, as well as measuring phytotoxicity in soybean crops treated with these herbicides. In both growth chamber and greenhouse conditions, plant height and shoot fresh weight of Acalypha australis increased as temperature increased. The variable to maximum fluorescence ratio (Fv/Fm), relative electron transport rate (ETR), plant height, leaf area, and shoot fresh weight of Acalypha australis were higher at carbon dioxide concentrations of 800 ppm than at 400 ppm. The efficacy of a foliar herbicide, glufosinate, on Acalypha australis was lower at 30℃ than at 20℃ and 25℃ in the growth chamber condition and was also lower at 29℃ than at 21℃ and 25℃ in greenhouse conditions. In contrast, mecoprop efficacy on Acalypha australis was lower at 20℃ and 25℃ than at 30℃ in growth chamber conditions and lower at 21℃ and 25℃ than at 29℃ in greenhouse conditions. Glyphosate efficacy was lower at 21℃ than at 25℃ and 29℃ under greenhouse conditions. With soil herbicides, metolachlor and ethalfluraline, efficacies were higher at relatively high temperatures under both growth chamber and greenhouse conditions. However, in the case of linuron, the difference in efficacy was not observed under varying temperatures in both growth chamber and greenhouse conditions. When ¼ of the recommended glyphosate rates were applied to Acalypha australis, efficacy was lower under 800 ppm carbon dioxide concentrations than under 400 ppm. In contrast, when ¼ of the recommended rate of bentazone was applied to Acalypha australis, efficacy was higher under 800 ppm carbon dioxide concentrations than under 400 ppm. Despite application rates, glufosinate efficacy differed insignificantly under different carbon dioxide concentrations. When applied at ¼ of the recommended rate, the efficacy of ethalfuralin was higher under 800 ppm carbon dioxide concentrations than under 400 ppm. However, efficacies of other herbicides were not different despite varying carbon dioxide concentrations. Soybean phytotoxicity in crops treated with the recommended rate and twice the recommended rate of soil herbicides was not significantly different regardless of temperature and carbon dioxide concentrations. Overall, weed efficacy of some herbicides decreased in response to different temperatures and carbon dioxide concentrations. Therefore, new weed management methods are required to ensure high rates of weed control in conditions affected by climate change.

Nutritional quality evaluation of complementary baby food products in Korea according to food composition (국내 시판 간편 이유식의 식품 구성에 따른 영양적 질 평가)

  • Eun-Ju Lee;Jee-Young Yeon;Mi-Hyun Kim
    • Journal of Nutrition and Health
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    • v.56 no.5
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    • pp.537-553
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    • 2023
  • Purpose: The purpose of this study was to evaluate the nutritional quality of complementary baby food products sold in Korea according to the baby food stages and food composition. Methods: A total of 1,587 complementary food products sold online and offline between March and December 2021 were investigated. They ranged from liquid meals to solid rice for babies aged 5 to 36 months. Results: The number of intakes per packaged volume was 2.8 in Stage 1, 1.9 in Stage 2, 1.4 in Stage 3, and 1.1 in Stage 4 (p < 0.0001). The dietary variety scores (DVS) of the complementary baby food products were 3.4 in Stage 1, 5.5 in Stage 2, 7.1 in Stage 3, and 9.7 in Stage 4 (p < 0.0001) and showed a significant increase in the later stages. The Korean dietary diversity score (KDDS) significantly increased from 2.3 in Stage 1, to 2.8 in Stage 2, 3.0 in Stage 3, and 3.4 in Stage 4 (p < 0.0001). The higher the baby food stage, the higher the proportion of grains/meat/vegetable ingredients. The ratio of protein intake to Adequate Intake (AI) or Recommended Nutrition Intake (RNI) was higher in products with a KDDS of 3 points or more, or in products with 2 points or fewer in Stages 1 and 2 (p < 0.0001, respectively). The ratio of protein intake to RNI increased as the KDDS score increased in Stages 3 and 4 (p < 0.0001, respectively). For all stages of baby foods, the ratio of protein intake to AI or RNI was high in products that included the meat group (beans, nuts, meat, eggs, fish, and shellfish) (p < 0.0001, respectively). Conclusion: Continuous research and nutritional evaluation are required for establishing nutrient content standards for commercially available baby foods, considering breast milk intake.

Assessment of water supply reliability in the Geum River Basin using univariate climate response functions: a case study for changing instreamflow managements (단변량 기후반응함수를 이용한 금강수계 이수안전도 평가: 하천유지유량 관리 변화를 고려한 사례연구)

  • Kim, Daeha;Choi, Si Jung;Jang, Su Hyung;Kang, Dae Hu
    • Journal of Korea Water Resources Association
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    • v.56 no.12
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    • pp.993-1003
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    • 2023
  • Due to the increasing greenhouse gas emissions, the global mean temperature has risen by 1.1℃ compared to pre-industrial levels, and significant changes are expected in functioning of water supply systems. In this study, we assessed impacts of climate change and instreamflow management on water supply reliability in the Geum River basin, Korea. We proposed univariate climate response functions, where mean precipitation and potential evaporation were coupled as an explanatory variable, to assess impacts of climate stress on multiple water supply reliabilities. To this end, natural streamflows were generated in the 19 sub-basins with the conceptual GR6J model. Then, the simulated streamflows were input into the Water Evaluation And Planning (WEAP) model. The dynamic optimization by WEAP allowed us to assess water supply reliability against the 2020 water demand projections. Results showed that when minimizing the water shortage of the entire river basin under the 1991-2020 climate, water supply reliability was lowest in the Bocheongcheon among the sub-basins. In a scenario where the priority of instreamflow maintenance is adjusted to be the same as municipal and industrial water use, water supply reliability in the Bocheongcheon, Chogang, and Nonsancheon sub-basins significantly decreased. The stress tests with 325 sets of climate perturbations showed that water supply reliability in the three sub-basins considerably decreased under all the climate stresses, while the sub-basins connected to large infrastructures did not change significantly. When using the 2021-2050 climate projections with the stress test results, water supply reliability in the Geum River basin was expected to generally improve, but if the priority of instreamflow maintenance is increased, water shortage is expected to worsen in geographically isolated sub-basins. Here, we suggest that the climate response function can be established by a single explanatory variable to assess climate change impacts of many sub-basin's performance simultaneously.

A Study of the Influence of Start-up New Product Preannouncing Information Attributes on Purchase Intention: Focused on UTAUT2 (프리어나운싱 정보속성이 스타트업 신제품 구매의도에 미치는 영향에 관한 연구: 확장된 통합기술수용이론(UTAUT2)을 중심으로)

  • Byung-chul Han;Jae-Hyun You
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.5
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    • pp.1-16
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    • 2023
  • Due to imbalances in supply and demand within the labor market, start-ups have emerged as crucial players in the generation of high-quality employment opportunities, particularly in stagnant job markets. In response to this trend, governments are allocating substantial financial and human resources to initiatives that support start-up development. This has led to an increasing rate of engagement in start-up ventures across diverse age groups, not limited to younger individuals. Start-ups are enterprises focused on the commercialization of innovative ideas with the aim of achieving profitability in the marketplace. Research concerning the successful market integration of new products and the attainment of sustainable growth is pivotal. Such research is instrumental not only for the success of start-ups but also for realizing the broader social functions and contributions that these enterprises can offer. Previous research has often examined new product market-entry strategies, often referred to as new product marketing, particularly for large companies and SMEs. However, there is a gap in studies focusing on prototype marketing strategies specific to start-ups. Thus, this study aims to examine the impact of Pre-announcing marketing strategies on the market attention garnered by start-ups with low recognition and limited infrastructure, and how such attention contributes to their sustainable growth. Specifically, the study aims to uncover the causal relationship between information attributes like relevance, vividness, and novelty in building customer relationships, and their impact on purchase intentions influenced by performance expectations and hedonic motivations. In terms of Pre-announcing information attributes, relevance, vividness, and novelty positively influence performance expectations and hedonic motivations as outlined in the extended Unified Theory of Acceptance and Use of Technology (UTAUT2). These factors, in turn, positively impact the purchase intention for pre-announced new products from start-ups. These findings are expected to provide both theory and practical insights into the factors influencing market entry through the use of Pre-announcing marketing strategies for start-up new products.

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Hydrographic Structure Along $131.5^{\circ}W$ in the Northeastern Pacific in July-August 2005 (2005년 7-8월에 관측한 북동태평양 $131.5^{\circ}W$의 해수특성 및 해양구조)

  • Shin, Hong-Ryeol;Hwang, Sang-Chul
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.13 no.3
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    • pp.190-199
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    • 2008
  • To investigate hydrographic structure and characteristics of the tropical ocean in the eastern and the western Pacific, CTD(Conductivity-Temperature-Depth) data along $131^{\circ}W$ and $137^{\circ}-142^{\circ}E$ in July-August 2005 were analyzed. Sea surface temperature along $131.5^{\circ}W$ in summer is highest in the Equatorial Counter Current(ECC) because of the high-temperature water greater than $28^{\circ}C$ moving through the ECC from the western Pacific to the eastern Pacific in spring and summer. Based on the evidence of the presence of low salinity and high dissolved oxygen water in the North Equatorial Current(NEC), we suggested that the low salinity water moved from the Gulf of Panama to the east of Philippine along the North Equatorial Current(NEC). The South Equatorial Current(SEC) had the most saline water from surface to deep layer because the saline water from the Subtropical South Pacific Ocean moved to the north. The salinity minimum layer was observed at 500-1500 m depth along $131.5^{\circ}W$. The water mass with the salinity minimum layer in the north of $5^{\circ}N$ came from the North Pacific Intermediate Water(NPIW) and that in the south of $5^{\circ}N$ came from the Antarctic Intermediate Water(AAIW), which was more saline than the NPIW. Cyclonic cold eddy with a diameter of about 200km was found in $4-6^{\circ}N$. Sea surface temperature along $131.5^{\circ}W$ in the eastern Pacific was lower than along $137^{\circ}-142^{\circ}E$ in the western Pacific; on the other hand, sea surface salinity in the eastern Pacific was higher than in the western Pacific. Subsurface saline water from the Subtropical South Pacific Ocean was less saline in the eastern Pacific than in the western Pacific. Salinity and density(${\sigma}_{\theta}$) of the salinity minimum layer south of $14^{\circ}N$ was higher in the eastern Pacific than in the western Pacific.