• 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.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.259-262
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• 2003

In the Republic of Korea, Ministry of Construction & Transportation and Korea Water Resources Corporation manage the national groundwater monitoring network at the 169 stations and will organize the supplementary groundwater monitoring network at the 10,000 stations by 2011 year. The method that organizes the monitoring network was developed using the Analytic Hierarchy Process with pairwise comparison. Several estimation factors for the estimating every district were selected to reflect each district conditions. Their weighting value was decided by pairwise comparison and questions to the experts about groundwater The optimal number of groundwater monitoring well was calculated through the developed method. To verify this method, groundwater was monitored in Jeonju city by way showing the example. The study area In Jeonju city needs 7 stations for the supplementary groundwater monitoring network. The results monitored in 7 stations inferred the groundwater level around the study area by Kriging. The mean of residual between inferred groundwater level value from Kriging and actual groundwater level is rather low. Furthermore, the mean and standard deviation of residual between inferred groundwater level change and actual groundwater change is much lower. The Fact that 7 monitoring stations are sufficient for observing the groundwater condition in the study area makes it possible for suggested monitoring number to be proper.

• Journal of Veterinary Clinics
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• v.18 no.4
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• pp.334-340
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• 2001

This study was conducted to investigate changes in blood properties of high potassium (HK) phenotype Jindo dogs (15kg$\pm$2kg) after daily oral administration with water celery extracts (10 ml/kg) for 7 days. Blood samples were collected for three days in a row before administration of water celery extracts. After water celery extracts administration, blood samples were collected at 3h, 6h, 9h and then on daily basis until day 10 post administration (PA). At day 15, final sample was collected. Blood samples were analyzed on the basis of red blood cell (RBC), white blood cell (WBC), packed cell volume (PCV), hemoglobin (Hb) concentration, mean corpuscular volume(MCV), mean corpuscular hemoglobin concentration(MCHC), gluthathione concentration(GSH) and met-hemoglobin(Met-Hb) concentration. The significant changes (p<0.01, p<0.05) of RBCs were shown at 3 h to day 5, and days 7 and 9 after administration. PCV values were decreased form 3 h to day 10 after administration. Mean Hb concentration showed significant increase as 3 h to day 3, and day 6 to day 9 after administration. The significant changes (p<0.05) of WBCs were shown at 9 h and day 1 after administration. The increased numbers of MCV were detected at days 6 to 9 after administration (p<0.05, p<0.01). The significant changes of MCHC were shown at 9h and day 1 after administration. The significant increases (p<0.01, p<0.05) of GSH concentration were detected at days 1, 6 and 7 after administration. In Met-Hb concentration, the significant increases (p<0.05) occurred at only 9h and day 7 after administration, The significant increases (p<0.01, p<0.05) of reticulocyte were detected at days 2, 4, 5, 6 and 7. Data from blood samples collected at day 15 after administration showed that all of blood analysis results returned to normal level, compared to controls.

• Journal of Ecology and Environment
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• v.43 no.1
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• pp.22-30
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• 2019

Background: Piton du Milieu (PdM) impounding reservoir is suspected to be eutrophic based on the elevated level of orthophosphate and nitrate. Water supplies from three adjacent rivers are primarily thought to contribute to the nutrient enrichment of the reservoir. It is also suspected that there is leaching of orthophosphate, nitrate and organic matter into the rivers during rainfall events and also as a result of anthropogenic activities within the catchment area. The aim of this study was to ascertain the impact of nutrient loading on the water quality of PdM water and on the population of freshwater microalgae in the reservoir. The enumeration and identification of algae from PdM were performed by differential interference contrast microscopy. Dissolved oxygen (DO) and pH were determined by electrometric methods, whereas nutrient levels, silica and total organic carbon (TOC) were determined by instrumentation techniques. Results: Annual mean orthophosphate, nitrate and total organic carbon input from the three feeders within the catchment area of PdM reached levels as high as 0.09 mg/L, 0.4 mg/L and 2.62 ppm respectively. Over a 12-month period, mean TOC concentration in the reservoir was 2.32 ppm while the mean algal cell count was 4601 cells/mL. The dominant algal species identified were Oscillatoria, Cyclotella, Navicula and Cosmarium. Conclusion: This study highlights the trophic state of the reservoir water and clearly points to the need for constant monitoring in order to avoid the occurrence of an impending harmful algal bloom.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.5
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• pp.408-417
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• 2007

Recently, an artificial beach has been constructed compensating for loss of the natural one caused by the development of coastal area, as well as serving as a location for recreational activities such as sea bathing. It is well known that some structure should be constructed to protect an artificial beach from the outflow due to wave action of the reclaimed sand. In general, dike is utilized as the structure to protect an artificial beach. And, one of the factors which may need to be taken into consideration for stability of dike on seabed foundation is the ground water behavior behind dike. However, the interrelated phenomena of nonlinear wave and ground water response have relatively little attention although these interactions are important for stability of structure and sand suction to the artificial beach. In this paper, the numerical wave tank was developed to clarify nonlinear wave, dike and ground water dynamic interaction, which can simulate the difference of ground water and mean water level. Using the developed numerical wave tank, the present study investigates how variation of ground water level influences hydrodynamic characteristics in seabed around dike and numerically simulates the wave fields, pore flow patterns, pore water pressures and vorticities according to variation of ground water level. Numerical results explain well how hydrodynamic characteristics in seabed around dike is affected by the variation of ground water level.

• The Korean Journal of Physiology
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• v.2 no.1
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• pp.47-52
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• 1968

Twenty white rabbits anesthetized with nembutal (30 mg/kg) were employed in this experiment. Five of them served as controls; the remaining rabbits as experimental group were subjected to irreversible hemorrhagic shock. Shock was induced by bleeding the animals until mean blood pressure decreased to a level of 50-40 mmHg. This level of pressure was maintained for 3-4 hours, after which the drawn blood was reinfused. The reinfusion of blood caused the elevation of arterial pressure almost the control level for some minutes, after which a gradual and progressive decline of blood pressure became evident. This decline was thought to be the result from irreversible hemorrhagic shock. When mean blood pressure declined to less than 50 mmHg, chest was opened and samples of arterial blood and left ventricular muscle were taken. Left ventricular muscle and blood plasma were analyzed for potassium, sodium, chloride and water content. Blood glucose concentration was determined by Somogyi-Nelson's method. Extracellular and intracellular myocardial water and electrolyte content were calculated on the basis that electrolytes are distributed between plasma water and interstitial water according to Gibbs-Donnan equilibrium. In this calculation extracellular water was substituted for Na space. The findings obtained were as follows: 1. The concentration of blood glucose was 87mg% in the controls and it rose to 222 mg% in shock (P<0.01). 2. Plasma potassium elevated significantly from 3.3 mEq/l in controls to 8.0 mEq/l in shock (P<0.01), while small decreases in sodium (151-146 mEq/l) and chloride (102-96 mEq/l) were observed (P<0.3, P<0.1), 3. The changes of blood water content (83.1-84.3%) and cardiac water content (77.5-78.3 gm/100gm WT) were observed. 4. In control animals myocardial potassium levels which averaged 30.2 mEq/100 gmDT rose significantly to 40.3 mEq/100 gmDT in shock (P<0.01), while moderate decreases in sodium(16.3-14.3 mEq/100 gmDT) were observed in shock. 5. The calculated transmembrane resting potential of left ventricular muscle of control animals averaged 95 mV, while rabbits in shock averaged 77 mV. (P <0.01). The findings of this experiment do not correspond with the conclusions that myocardial depression seems to be the cause of irreversible hemorrhagic shock, because the excitability of heart muscle is elevated. From the point of view that the lowered transmembrane resting potential, the cause of death in terminal stage of irreversible hemorrhagic shock may be ventricular fibrillation. It can't be said, however, that the lowered transmembrane resting potential is responsible for the transition from reversible to irreversible hemorrhagic shock. The marked increase in blood glucose suggested that glycogenolysis in the liver is favorably active in shock.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.7 no.4
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• pp.305-312
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• 1995

In general, the radiation stresses based on the linear wave theory are overestimated which result in the discrepancy between the computed results and laboratory data of mean water level in the surf zone. Oh (1995) estimated the mean water level by using Svendsen's radiation stress model (1984) and compared with the experimental data. In this study. the computed results showed good agreements with the experimental data in the case of small wave steepness. while the results were overestimated in the case of large wave steepness. In this paper. the dimensionless radiation stress proposed by Svendsen (1984) is expressed in terms of relative water depth at breaking point and deep water wave steepness. The computed results are compared with the results calculated by d linear wave theory, Stive's model (1984). Sawaragi et al's model (1984) based on the spectrum of breaking wave components. and published laboratory data. The computed results of the modified Svendsen's model arc favourably compared with the laboratory data.

• Journal of the Korean Geographical Society
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• v.32 no.4
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• pp.403-420
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• 1997

Dodaecheon is a small river flowing into Asan Bay which is located in the middle part of the West Coast of the Korean Penninsula. We have investigated the change of depositional environment in Dodaecheon river basin during the middle Holocene. In the course of the research, the methods such as boring, radiocarbon dating, diatom and pollen analysis were employed. The Holocene deposits of the studied area are consisted of peat and gray silt layers, and contain many plooen and diatom fossils. Based on the results of diatom and pollen analysis, we conclude that the gray silt layers were sedimented owing to the transgression in the middle Holocene, and the peat layers by the regression or stabilzation of the sea level. The shoreline in the Post Glacial Age reached to the rivemouth of Dodaecheon at ca. 7,000 years before present(y. BP) and at that time the high tide sea-level(mean high water level of spring tide) rose to ca. 3m above present mean sea-level(m.a.s.l.). Since then to ca. 6,000y. BP, the high tide sea-level arrived to ca. 5m above present mean sea level further repeating minor transgressions and regressions. The peat layers of the coastal lowland of the West Coast were formed by the sea level fluctuations from 7,000 y. BP to 3,000 y. BP, and they were distributed 2 to 6 meters higher than the mean sea level of the present day. Most of them sedimented due to the high tide level are older and higher than those of the East Coast which were formed at the swale in the low tidal range environment.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.116-116
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• 2020

Gilgit-Baltistan (GB) is a highly mountainous and remote region covering 45% of Upper Indus Basin (UIB) with around 1.8 million population is vulnerable to climate change and socio-economic growth makes water resources management and planning more complex. To understand the water scarcity in the region this study is carried out to project water supply and demand for agricultural and domestic sector under various climate-socio-economic scenarios in five sub catchments of GB i.e., Astore, Gilgit, Hunza, Shigar and Shyok for a period of 2015 to 2050 using Water Evaluation and Planning (WEAP) model. For climate change scenario ensembled mean of three global climate models (GCMs) was used under three different Representative Concentration Pathway (RCP) scenarios (RCP2.6, RCP6.0 and RCP8.5). The Shared Socioeconomic Pathways (SSPs) and agricultural Land Development (LD) scenarios were combined with climate scenarios to develop climate-socio-economic scenario. Our results indicate that the climate change and socio-economic growth would create a gap between supply and demand of water in the region, with socio-economic growth (e.g. agricultural and population) as dominant external factor that would reduce food production and increase poverty level in the region. Among five catchments only Astore and Gilgit will face shortfall of water while Shyoke would face shortfall of water only under agricultural growth scenarios. We also observed that the shortfall of water in response to climate-socio-economic scenarios is totally different over two water deficient catchments due to its demography and geography. Finally, to help policy makers in developing regional water resources and management policies we classified five sub catchments of UIB according to its water deficiency level.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.6
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• pp.694-703
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• 2012

To understand the characteristics of sedimentary and benthic environments in habitats of naturally-occurring intertidal benthic macroalgae, various geochemical parameters of sediment (grain size, ignition loss [IL], chemical oxygen demand [COD], and acid volatile sulfur [AVS]) and pore water (temperature, salinity, pH, and nutrients) were measured in the southern intertidal zone of Hampyeong Bay at two month intervals from April to October 2009. Ecological characteristics including the distribution and biomass of benthic macroalgae were also investigated. Benthic macroalgae were distributed below 4 to 5 m depth from mean sea level near the lower portion of the intertidal zone where air exposure time is relatively short. The distribution area and biomass of benthic macroalgae gradually decreased during the study period. The surface sediments in the benthic algal region were mainly composed of finer sediments, such as slightly gravelly mud and mud. The temperature, salinity, pH, and nutrient concentrations (except dissolved inorganic nitrogen) in pore water did not differ in regions with and without benthic macroalgae, whereas the mean grain size and the concentrations of IL, COD, and AVS in sediments were much higher in regions harboring benthic macroalgae. The correlation between mean grain size and IL in sediments displayed two distinct gradients and the slope was much steeper in regions harboring benthic macroalgae, indicating that the content of organic matter in benthic algal region is not solely dependent on mean grain size. Our results indicate that the benthic macroalgae in the southern intertidal zone of Hampyeong Bay play an important role in the accumulation of organic matter in sediment.