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A Study on Facilities Damage Characteristics Caused by Forest Fire in Goseong-Gun (고성산불로 인한 시설물피해특성 연구)

  • Yeom, Chanho;Lee, Si-young;Park, Houngsek;Kwon, Chungeun
    • Journal of the Society of Disaster Information
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    • v.15 no.4
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    • pp.469-478
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    • 2019
  • Purpose: In this studies we examine the facilities damage characteristics caused by forest fire. Therefore, we surveyed damaged facilities from forest fire which was occurred on Goseong-Gun on march 28 in 2019.(damaged areas was 40ha) The types of facilities uses were house, public facility, warehouse and so on. 17 facilities were destroyed. The purpose of this study was to for establishing a disaster safety village in rural areas where damage from a similar type of disaster occurs repeatedly by conducting the consciousness survey targeting at experts and disaster safety officials in a local government. Method: We surveyed meteorological factors(temperature, wind speed, wind direction, humidity) per a minute for analyzing weather condition on Goseong-Gun when forest fire was occurred, spread and extinguished. And we surveyed forest fire risk factors(a slope degree, a slope direction, a geographical feature, a distance between forest and facility, main species, the existence of crown fire ignition, the direction of facility, the main material of building) around 10 damaged facilities. Finally, we analyzed damage pattern of facilities using meteorological factor and forest fire reisk fator Result: The weather condition of Kanseonng AWS (No.517) was high temperature, arid and strong wind, when the forest fire was occurred and spread. An average wind speed was 4.1m/s and the maximum wind speed was 11.6m/s. The main direction of wind was W(225~315°). Damaged facilities were located on the steep slope area and on the mountaintop. The forest density around facilities was high and main species was korean red pine. The crown fire was occurred in the forest around damaged facilities. The average distance was 13.5m from forest to facilities. When the main matarial of building was made by fire resistance materials (for example, rainforced concrete), the damage was slightly. on the other hand, when by flammable material (for example, a Sandwich Panel), the facilities were totally destroyed Conclusion: The results of this research which were the thinning around house, making a safety distance, the improvement of main material of building and etc, will be helpful for establishing a counter measure for a forest fire prevention of facilities in wild land urban interface

Modern Paper Quality Control

  • Olavi Komppa
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2000.06a
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    • pp.16-23
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    • 2000
  • The increasing functional needs of top-quality printing papers and packaging paperboards, and especially the rapid developments in electronic printing processes and various computer printers during past few years, set new targets and requirements for modern paper quality. Most of these paper grades of today have relatively high filler content, are moderately or heavily calendered , and have many coating layers for the best appearance and performance. In practice, this means that many of the traditional quality assurance methods, mostly designed to measure papers made of pure. native pulp only, can not reliably (or at all) be used to analyze or rank the quality of modern papers. Hence, introduction of new measurement techniques is necessary to assure and further develop the paper quality today and in the future. Paper formation , i.e. small scale (millimeter scale) variation of basis weight, is the most important quality parameter of paper-making due to its influence on practically all the other quality properties of paper. The ideal paper would be completely uniform so that the basis weight of each small point (area) measured would be the same. In practice, of course, this is not possible because there always exists relatively large local variations in paper. However, these small scale basis weight variations are the major reason for many other quality problems, including calender blacking uneven coating result, uneven printing result, etc. The traditionally used visual inspection or optical measurement of the paper does not give us a reliable understanding of the material variations in the paper because in modern paper making process the optical behavior of paper is strongly affected by using e.g. fillers, dye or coating colors. Futhermore, the opacity (optical density) of the paper is changed at different process stages like wet pressing and calendering. The greatest advantage of using beta transmission method to measure paper formation is that it can be very reliably calibrated to measure true basis weight variation of all kinds of paper and board, independently on sample basis weight or paper grade. This gives us the possibility to measure, compare and judge papers made of different raw materials, different color, or even to measure heavily calendered, coated or printed papers. Scientific research of paper physics has shown that the orientation of the top layer (paper surface) fibers of the sheet paly the key role in paper curling and cockling , causing the typical practical problems (paper jam) with modern fax and copy machines, electronic printing , etc. On the other hand, the fiber orientation at the surface and middle layer of the sheet controls the bending stiffness of paperboard . Therefore, a reliable measurement of paper surface fiber orientation gives us a magnificent tool to investigate and predict paper curling and coclking tendency, and provides the necessary information to finetune, the manufacturing process for optimum quality. many papers, especially heavily calendered and coated grades, do resist liquid and gas penetration very much, bing beyond the measurement range of the traditional instruments or resulting invonveniently long measuring time per sample . The increased surface hardness and use of filler minerals and mechanical pulp make a reliable, nonleaking sample contact to the measurement head a challenge of its own. Paper surface coating causes, as expected, a layer which has completely different permeability characteristics compared to the other layer of the sheet. The latest developments in sensor technologies have made it possible to reliably measure gas flow in well controlled conditions, allowing us to investigate the gas penetration of open structures, such as cigarette paper, tissue or sack paper, and in the low permeability range analyze even fully greaseproof papers, silicon papers, heavily coated papers and boards or even detect defects in barrier coatings ! Even nitrogen or helium may be used as the gas, giving us completely new possibilities to rank the products or to find correlation to critical process or converting parameters. All the modern paper machines include many on-line measuring instruments which are used to give the necessary information for automatic process control systems. hence, the reliability of this information obtained from different sensors is vital for good optimizing and process stability. If any of these on-line sensors do not operate perfectly ass planned (having even small measurement error or malfunction ), the process control will set the machine to operate away from the optimum , resulting loss of profit or eventual problems in quality or runnability. To assure optimum operation of the paper machines, a novel quality assurance policy for the on-line measurements has been developed, including control procedures utilizing traceable, accredited standards for the best reliability and performance.

Changes in Temperature and Light Distribution in the Rice Crop Canopy at the Different Growth Stages (수도군락내(水稻群落內) 온도(溫度) 및 광분포(光分布)의 시기별(時期別) 변화(變化))

  • Lee, Jeong-Taek;Jung, Yeong-Sang;Ryu, In-Soo;Kim, Byung-Chan
    • Korean Journal of Soil Science and Fertilizer
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    • v.17 no.2
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    • pp.108-113
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    • 1984
  • To find out the differences in micro-meteorological changes in the rice plant canopy at the different growing stages, Seokwang-byo, a high yielding variety, was cultivated with three planting densities of 50, 80 and 110 hills per $3.3m^2$ in 1982, and Seokwangbyo and Chucheong-byo, a local variety, were planted with a density of 80 hills per $3.3m^2$. Air temperature in plant canopies, water and soil temperatures were continuously monitored throughout the growing period. The relationship between solar radiation interception and leaf area indices at different height in the canopy also was studied. The results were as follows: 1. Air temperature in the densely planted canopy was 1 to $1.5^{\circ}C$ higher than that in the sparsely planted one at the early growing stage, but was inverted after 60 days of transplanting. The vertical distribution of temperature in the canopies showed that air temperature at 10 cm height from the ground was higher than that at 30 cm height. The temperature inversion occurred showing lower temperature at the 10 cm height than at the 30 cm height. 2. The highest temperature of a day in the canopy occurred at 14:00 to 15:00 Korean Standard Time same as that of air temperature, but approached to the solar noon time as the plants grew thick. 3. The air temperature in the canopy became higher than water temperature when the leaf area indices were 4.6 for Chucheongbyo and 5.2 for Seokwangbyo, and the light penetration ratios were 40 percents. 4. Light extinction coefficients of the 50 to 70 cm layer of the canopies were 0.3 to 0.5 but decreased at the lower layers. 5. Albedo of the canopies was 0.4 in the morning and evening while that was about 0.25 at noon. The difference in albedo between Seokwangbyo and Chucheongbyo could be recognized with the difference in leaf structure.

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A Study on the Damage of Pine Stand by Snowfall (항설(降雪)에 의(依)한 소나무 임분(林分)의 피해(被害)에 관(關)한 연구(硏究))

  • Ma, Ho Seop;Kang, Wee Pyeong;Kim, Jai Saing
    • Journal of Korean Society of Forest Science
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    • v.73 no.1
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    • pp.63-69
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    • 1986
  • In general, the snow injury in forestry is an unusual disaster. The degree of snow injury varies greatly depending on stand density and the local topography. This study was conducted to investigate the snow injury in analyzing the demaged by snow-fall in Jinju, Gyeongsangnamdo. The results obtained were summarized as follow; Among 466 total damaged trees, 425 trees were broken and 41 trees were uprooted, the ratio of damage were 5.22%, 2.49%, 0.92% and 0.2% for Pinus densiflora, Pinus thunbergii, Pinus rigida, Alnus hirsuta respectively. The 95% of the damage trees were in the range of 3 to 11 m for height and in the range of 3 to 20 cm for D. B. H.. The directions of the damage trees had a large influence by direction of the wind, but they shown at high tendency to aspect of the slope relatively. The 82% of the damaged trees ranged from 11 to 24 age. The ratio of broken height ($H_B/H$) indicated that the damage was most frequent in the part of stem as 24%, 45%, 31% in the part of the root collar (0.1), stem (0.2-0.4), crown (0.5-1.0) respectively. In general, trees with stem-form coefficient ($H_B/D$) over 0.7-0.8 are apt to suffer by snow damage. The average of stem-form coefficient of trees in this area was 1.06. Therefore, the ratio of damage was high tendency as 3.14%. These results indicate that it is necessary to apply pertinent tending which will increase in resistance of snow damage. As avalanches from the flank of soil erosion rise in an importance matter in present, it should also be considered to measures for prevention and restoration.

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Soil Characteristic of Plow and Compaction Layer in Fluvio-marine Deposit Paddy Soil (하해혼성 충적층 논토양 작토층과 경반층의 토양특성)

  • Yang, Chang-Hyu;Kim, Taek-Kyum;Ryu, Jin-Hee;Kim, Jae-Duk;Jung, Kwang-Yong
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.5
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    • pp.364-370
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    • 2009
  • This study was conducted to survey, analyze on the compaction layer and the plow layer at Jeonbug and Jisan series paddy soil, which is the representative soil in fluvio-marine and local alluvium, respectively. The depths of surface soil were 12.6 and 12.7 cm in Jeonbug and Jisan series, respectively. A plowing depth was 10.5 cm. The properties of compaction layer in two soil series were as follows. The hardness were $14.7kg\;cm^{-2}(25.3mm)$ and $8.7kg\;cm^{-2}(22.1mm)$ in Jeonbug and Jisan series, respectively. The thickness were 22.3 cm and 17.8 cm in Jeonbug and Jisan series, respectively. The depth of soil compaction, which means depth from surface, were 15 and 20 cm in Jeonbug and Jisan series, respectively. The relationship between the hardness of compaction layer and the depth of surface soil showed negative correlation, however relationship between the hardness and the thickness of compaction layer showed positive correlation. Soil temperature was lower in compaction layer than in plow layer. This temperature differences between compaction layer and plow layer were from 1.0 to $2.5^{\circ}C$ in Jeonbug series and from 0.7 to 2.1 in Jisan series. The soil physical properties of compaction layer were higher in bulk density and solid phase and lower in porosity and gaseous phase than those of plow layer in all soil series. The soil chemical properties of compaction layer were higher in pH, content of available silicate, exchangeable calcium and magnesium but lower in total nitrogen, content of organic matter and available phosphate than those of plow layer in all soil series. Cation exchangeable capacity and content of exchangeable potassium were similar between compaction layer and plow layer in Jeonbug series, however, in Jisan series these were lower in compaction layer than in plow layer. Elution amount of inorganic nitrogen were lower in compaction layer than in plow layer in all soil series. The content of soluble Fe and Mn were plenty in compaction layer compared with plow layer and these tendency was apparent in Jeonbug series. The water depth decrease were fast until the latter part of June, and were slow as $1{\sim}3mm\;day^{-1}$ for July and August, and were fast again from september. Rice roots distributions as each soil series and tillage method were 25 cm at rotary plowing in Jeonbug series, 30 cm at deep plowing in Jeonbug series, and 20 cm at tillage in Jisan series. Dry weight per m2 at heading stage were much in order of deep plowing in Jeonbug series, rotary plowing in Jeonbug series, and tillage in Jisan series.

Thrips Infesting Hot Pepper Cultured in Greenhouses and Variation in Gene Sequences Encoded in TSWV (시설재배지 고추를 가해하는 총채벌레류와 TSWV 유전자 서열 변이)

  • Kim, Chulyoung;Choi, Duyeol;Kang, Jeong Hun;Ahmed, Shabbir;Kil, Eui-Joon;Kwon, Gimyeon;Lee, Gwan-Seok;Kim, Yonggyun
    • Korean journal of applied entomology
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    • v.60 no.4
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    • pp.387-401
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    • 2021
  • Thrips infesting hot peppers were monitored in greenhouses using yellow sticky traps. In addition, the hot peppers infected with tomato spotted wilt virus (TSWV) were observed during the monitoring period. The flower thrips (Frankliniella intonsa) were initially trapped at a low density just after transplanting seedlings of hot peppers at late March. The western flower thrips (Frankliniella occidentalis) were trapped after mid April. These two thrips represented more than 98% of the total thrips attracted to the traps after May, in which F. intonsa showed higher occurrence frequency than F. occidentalis. The total number of thrips had two peaks at mid May with a small and short-term peak and at June-July with a large and long-term peak. The trapped thrips exhibited inconsistent sex ratios, suggesting a seasonal parthenogenesis. Different geographical populations were varied in cytochrome oxidase I sequences, in which local populations in Andong shared a high sequence similarity. TSWV-infected hot peppers, which might be mediated by these two thrips species, were observed and confirmed by an immunoassay kit and a molecular diagnosis using RT-PCR. In addition, the TSWV was detected in F. occidentalis collected from the infected hot peppers. Three open reading frames (NSS, N, and NSM) of the isolated TSWV genomes were sequenced and showed multiple point mutations containing missense mutations among geographical variants. When the isolated TSWV was fed to nonvirulent thrips of F. occidentalis, the virus was detected in both larvae and adults. However, the viral replication occurred in larvae, but not in adults.

Geographical Characteristics of PM2.5, PM10 and O3 Concentrations Measured at the Air Quality Monitoring Systems in the Seoul Metropolitan Area (수도권 지역 도시대기측정소 PM2.5, PM10, O3 농도의 지리적 분포 특성)

  • Kang, Jung-Eun;Mun, Da-Som;Kim, Jae-Jin;Choi, Jin-Young;Lee, Jae-Bum;Lee, Dae-Gyun
    • Korean Journal of Remote Sensing
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    • v.37 no.3
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    • pp.657-664
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    • 2021
  • In this study, we investigated the relationships between the air quality (PM2.5, PM10, O3) concentrations and local geographical characteristics (terrain heights, building area ratios, population density in 9 km × 9 km gridded subareas) in the Seoul metropolitan area. To analyze the terrain heights and building area ratios, we used the geographic information system data provided by the NGII (National Geographic Information Institute). Also, we used the administrative districts and population provided by KOSIS (Korean Statistical Information Service) to estimate population densities. We analyzed the PM2.5, PM10, and O3 concentrations measured at the 146 AQMSs (air quality monitoring system) within the Seoul metropolitan area. The analysis period is from January 2010 to December 2020, and the monthly concentrations were calculated by averaging the hourly concentrations. The terrain is high in the northern and eastern parts of Gyeonggi-do and low near the west coastline. The distributions of building area ratios and population densities were similar to each other. During the analysis period, the monthly PM2.5 and PM10 concentrations at 146 AQMSs were high from January to March. The O3 concentrations were high from April to June. The population densities were negatively correlated with PM2.5, PM10, and O3 concentrations (weakly with PM2.5 and PM10 but strongly with O3). On the other hand, the AQMS heights showed no significant correlation with the pollutant concentrations, implying that further studies on the relationship between terrain heights and pollutant concentrations should be accompanied.

A Numerical Study on the Characteristics of Flows and Fine Particulate Matter (PM2.5) Distributions in an Urban Area Using a Multi-scale Model: Part II - Effects of Road Emission (다중규모 모델을 이용한 도시 지역 흐름과 초미세먼지(PM2.5) 분포 특성 연구: Part II - 도로 배출 영향)

  • Park, Soo-Jin;Choi, Wonsik;Kim, Jae-Jin
    • Korean Journal of Remote Sensing
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    • v.36 no.6_3
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    • pp.1653-1667
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    • 2020
  • In this study, we coupled a computation fluid dynamics (CFD) model to the local data assimilation and prediction system (LDAPS), a current operational numerical weather prediction model of the Korea Meteorological Administration. We investigated the characteristics of fine particulate matter (PM2.5) distributions in a building-congested district. To analyze the effects of road emission on the PM2.5 concentrations, we calculated road emissions based on the monthly, daily, and hourly emission factors and the total amount of PM2.5 emissions established from the Clean Air Policy Support System (CAPSS) of the Ministry of Environment. We validated the simulated PM2.5 concentrations against those measured at the PKNU-AQ Sensor stations. In the cases of no road emission, the LDAPS-CFD model underestimated the PM2.5 concentrations measured at the PKNU-AQ Sensor stations. The LDAPS-CFD model improved the PM2.5 concentration predictions by considering road emission. At 07 and 19 LST on 22 June 2020, the southerly wind was dominant at the target area. The PM2.5 distribution at 07 LST were similar to that at 19 LST. The simulated PM2.5 concentrations were significantly affected by the road emissions at the roadside but not significantly at the building roof. In the road-emission case, the PM2.5 concentration was high at the north (wind speeds were weak) and west roads (a long street canyon). The PM2.5 concentration was low in the east road where the building density was relatively low.

A Study on Method of Citizen Science and Improvement of Performance as a Ecosystem Conservation and Management Tool of Wetland Protected Areas (Inland Wetland) - Focused on the Target of Conservation·Management·Utilization in Wetland Protected Area Conservation Plan - (내륙 습지보호지역의 생태계 보전·관리 도구로서 시민과학연구 방법론 및 성과 제고 방안 - 습지보호지역 보전계획의 보전·관리·이용 목표를 중심으로 -)

  • Inae Yeo;Changsu Lee;Ji Hyun Kang
    • Journal of Environmental Impact Assessment
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    • v.32 no.6
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    • pp.450-462
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    • 2023
  • This study suggested methodology of Citizen Science as a tool of ecosystem conservation and management to achieve Wetland Protected Area (WPA) Conservation Plan and examined whose applicability in 3 WPAs (Jangrok of Gwangju metropolitan city, Madongho of Goseong in South Gyeongsang Province, and Incheongang estuary of Gochang in North Jeolla Province). It consists of a) figuring out main interests and stakeholder or beneficiaries of WPA and their information demand based on conservation, utilization, and management target in the WPA Conservation Plan, b) conducting research activities to gain outcome to address stakeholder's demand, and c) returning the research outcome to citizen scientists and making diffusion to the society. Based on the suggested method and process, citizen scientists conducted ecosystem monitoring (plants including Invasive Alien Plants, terrestrial insects, traces of mammals, discovering unknown wetland). As a result, citizen scientists contributed to collecting species information of 16 plans, 43 species of terrestrial insects, 5 mammals including Lutra lutra (Endangered Species I) and Prionailurus bengalensis (Endangered Species II). The authors constructed and provided distribution map of Invasive Alien Plants, which included information of location and density which citizen scientists registered, for Environment Agencies and local governments who manage 3 WPAs to aid data-based ecosystem policy, In further studies, not only accumulating research data and outcomes acquired from citizen science to suffice the policy demands but also deliberate reviewing policy applicability and social·economic ripple effect should be processed for the suggested Citizen Science in WPA to be settled down as a tool of ecosystem conservation and management.

Seasonal Circulation and Estuarine Characteristics in the Jinhae and Masan Bay from Three-Dimensional Numerical Experiments (3차원 수치모의 실험을 통한 진해·마산만의 계절별 해수순환과 염하구 특성)

  • JIHA KIM;BYOUNG-JU CHOI;JAE-SUNG CHOI;HO KYUNG HA
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.29 no.2
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    • pp.77-100
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    • 2024
  • Circulation, tides, currents, harmful algal blooms, water quality, and hypoxic conditions in Jinhae-Masan Bay have been extensively studied. However, these previous studies primarily focused on short-term variations, and there was limited detailed investigation into the physical mechanisms responsible for ocean circulation in the bays. Oceanic processes in the bays, such as pollutant dispersal, changes on a seasonal time scale. Therefore, this study aimed to understand how the circulation in Jinhae-Masan Bay varies seasonally and to examine the effects of tides, winds, and river discharges on regional ocean circulation. To achieve this, a three-dimensional ocean circulation model was used to simulate circulation patterns from 2016 to 2018, and sensitivity experiments were conducted. This study reveals that convective estuarine circulation develops in Jinhae and Masan Bays, characterized by the inflow of deep oceanic water from the Korea Strait through Gadeoksudo, while surface water flows outward. This deep water intrusion divides into northward and westward branches. In this study, the volume transport was calculated along the direction of bottom channels in each region. The meridional water exchange in the eastern region of Jinhae Bay is 2.3 times greater in winter and 1.4 times greater in summer compared to that of zonal exchange in the western region. In the western region of Jinhae Bay, the circulation pattern varies significantly by season due to changes in the balance of forces. During winter, surface currents flow southward and bottom currents flow northward, strengthening the north-south convective circulation due to the combined effects of northwesterly winds and the slope of the sea surface. In contrast, during summer, southwesterly winds cause surface seawater to flow eastward, and the elevated sea surface in the southeastern part enhances northward barotropic pressure gradient intensifying the eastward surface flow. The density gradient and southward baroclinic pressure gradient increase in the lower layer, causing a strong westward inflow of seawater from Gadeoksudo, enhancing the zonal convective circulation by 26% compared to winter. The convective circulation in the western Jinhae Bay is significantly influenced by both tidal current and wind during both winter and summer. In the eastern Jinhae Bay and Masan Bay, surface water flows outward to the open sea in all seasons, while bottom water flows inward, demonstrating a typical convective estuarine circulation. In winter, the contributions of wind and freshwater influx are significant, while in summer, the influence of mixing by tidal currents plays a major role in the north-south convective circulation. In the eastern Jinhae Bay, tidally driven residual circulation patterns, influenced by the local topography, are distinct. The study results are expected to enhance our understanding of pollutant dispersion, summer hypoxic events, and the abundance of red tide organisms in these bays.