• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.3
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• pp.147-153
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• 2013

There exist various types of the WEC (Wave Energy Converter), and among them, the point absorber is the most popularly investigated type. However, it is difficult to find examples of systematically measured data analysis for the design of the point absorber type of power buoy in the world. The study investigates the wave load acting on the point absorber type resonance power buoy wave energy extraction system proposed by Kweon et al. (2010). This study analyzes the time series spectra with respect to the three-year wave data (2002.05.01~2005.03.29) measured using the pressure type wave gage at the seaside of north breakwater of Hupo harbor located in the east coast of the Korean peninsula. From the analysis results, it could be deduced that monthly wave period and wave height variations were apparent and that monthly wave powers were unevenly distributed annually. The average wave steepness of the usual wave was 0.01, lower than that of the wind wave range of 0.02-0.04. The mode of the average wave period has the value of 5.31 sec, while mode of the wave height of the applicable period has the value of 0.29 m. The occurrence probability of the peak period is a bi-modal type, with a mode value between 4.47 sec and 6.78 sec. The design wave period can be selected from the above four values of 0.01, 5.31, 4.47, 6.78. About 95% of measured wave heights are below 1 m. Through this study, it was found that a resonance power buoy system is necessary in coastal areas with low wave energy and that the optimal design for overcoming the uneven monthly distribution of wave power is a major task in the development of a WEF (Wave Energy Farm). Finding it impossible to express the average spectrum of the usual wave in terms of the standard spectrum equation, this study proposes a new spectrum equation with three parameters, with which basic data for the prediction of the power production using wave power buoy and the fatigue analysis of the system can be given.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.5
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• pp.335-347
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• 2013

In February 2008, high storm waves due to a developed atmospheric low pressure system propagating from the west off Hokkaido, Japan, to the south and southwest throughout the East Sea (ES) caused extensive damages along the central coast of Japan and along the east coast of Korea. This study consists of two parts. In the first part, we estimate extreme storm wave characteristics in the Toyama Bay where heavy coastal damages occurred, using a non-hydrostatic meteorological model and a spectral wave model by considering the extreme conditions for two factors for wind wave growth, such as wind intensity and duration. The estimated extreme significant wave height and corresponding wave period were 6.78 m and 18.28 sec, respectively, at the Fushiki Toyama. In the second part, we perform numerical experiments on wave-structure interaction in the Fushiki Port, Toyama Bay, where the long North-Breakwater was heavily damaged by the storm waves in February 2008. The experiments are conducted using a non-linear shallow-water equation model with adaptive mesh refinement (AMR) and wet-dry scheme. The estimated extreme storm waves of 6.78 m and 18.28 sec are used for incident wave profile. The results show that the Fushiki Port would be overtopped and flooded by extreme storm waves if the North-Breakwater does not function properly after being damaged. Also the storm waves would overtop seawalls and sidewalls of the Manyou Pier behind the North-Breakwater. The results also depict that refined meshes by AMR method with wet-dry scheme applied capture the coastline and coastal structure well while keeping the computational load efficiently.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.3
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• pp.133-141
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• 2007

There are produced more than 600,000 tons of seaweeds every year along the coast of the Korea. Jeonnam province, south-west coast area, of Korea is producing 93% of total amounts of seaweeds. The laver, sea mustard, and tangleweed maintain stability in the output and has been exported as a simple product processing through drying or salting. It was evaluated the low value-added products and limited the expansion for the consumption of seaweeds. The seaweeds contains 40-60% carbohydrate and structurally different compared with land plant. The dietary fiber from seaweeds has been known the function of facilitating the bowl movement, excretion the heavy metal in the body, lowering the blood cholesterol level, anti-coagulant of blood, and anticancer. Especially, brown algae including sea mustard, seaweed fusiforme, and tangleweed contains alginic acid, laminarin, mannitol, fucoidan which are lowering the blood cholesterol level, lowering blood pressure, and fusion of blood clot. Agar-agar, carrageenan, and porphyran compound in red algae are known to antimutagenicity and anticoagulant function. In spite of potential of seaweed as a main bio-resource, there are lack of research to facilitate the consumption with its functional properties and consumers are unsatisfied with simple processing products. Also, the seaweed by-product dump into the sea and cause pollution of the seawater. Therefore, there are needed the scheme to promote the consumption of seaweeds. The development of value-added products, finding functional properties from seaweeds, development the functional feed for animal using seaweed by-products, and utilization of unused algae for food or other industrial uses will increase fisherman's income as well as serve as an aid for the people health due to its functional properties. Using by-product of seaweed and unexploited seaweed are needed to development of bio-degradable food packaging material and functional feed for animal.

• Korean Chemical Engineering Research
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• v.52 no.6
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• pp.814-820
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• 2014

In this work, hydrate inhibition performance of water-soluble polymers including pyrrolidone, caprolactam, acrylamide types were evaluated using torque measurement and high pressure differential scanning calorimeter (HP ${\mu}$-DSC). The obtained experimental results suggest that the studied polymers represent the kinetic hydrate inhibition (KHI) performance. 0.5 wt% polyvinylcaprolactam (PVCap) solution shows the hydrate onset time of 34.4 min and subcooling temperature of 15.9 K, which is better KHI performance than that of pure water - hydrate onset time of 12.3 min and subcooling temperature of 6.0 K. 0.5 wt% polyvinylpyrrolidone (PVP) solution shows the hydrate onset time of 27.6 min and the subcooling temperature of 13.2 K while polyacrylamide-co-acrylic acid partial sodium salt (PAM-co-AA) solution shows less KHI performance than PVP solution at both 0.5 and 5.0 wt%. However, PAM-co-AA solution shows slow growth rate and low hydrate amount than PVCap. In addition to hydrate onset and growth condition, torque change with time was investigated as one of KHI evaluation methods. 0.5 wt% PVCap solution shows the lowest average torque of 6.4 N cm and 0.5 wt% PAM-co-AA solution shows the average torque of 7.2 N cm. For 0.5 wt% PVP solution, it increases 11.5 N cm and 5.0 wt% PAM-co-AA solution shows the maximum average torque of 13.4 N cm, which is similar to the average torque of pure water, 15.2 N cm. Judging from the experimental results obtained by both an autoclave and a HP ${\mu}$-DSC, the PVCap solution shows the best performance among the KHIs in terms of delaying hydrate nucleation. From these results, it can be concluded that the torque change with time is useful to identify the flow ability of tested solution, and the further research on the inhibition of hydrate formation can be approached in various aspects using a HP ${\mu}$-DSC.

• Journal of Nutrition and Health
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• v.51 no.5
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• pp.386-399
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• 2018

Purpose: This study examined whether the supply of healthy Korean diets for 12 weeks is effective in improving the risk factors related to serum GGT and cardiovascular diseases in patients with hypertension and diabetes. Methods: This study selected 41 patients, who were treated with hypertension and diabetes. The Korean diet was composed of cooked-rice, soup, kimchi, and various banchan with one serving called bapsang, which emphasize proportionally high consumption of vegetables and fermented foods, moderate to high consumption of legumes and fish, and low consumption of animal foods. The control group was instead instructed to "eat and exercise as usual" while following the Korean Diabetes Association's dietary guidelines with an intake that can assist in glycemic control, maintain adequate weight, and meet the nutritional requirements. The Korean diet group (21 patients) were served three healthy Korean meals a day for 12 weeks, and the control group (20 patients, who trained in the diet guideline of diabetes) maintained their usual diabetic diet. The serum GGT, blood pressure, heart rate, glycemic control data, cardiovascular risk indicators, and changes in diet measured at the four visits (week 0, 4, 8, and 12) during the course of 12 weeks were compared and evaluated. Results: The serum GGT (p < 0.001), HbA1c (p = 0.004), heart rate (p = 0.007), weight (p = 0.002), Body Mass Index (p = 0.002), body fat mass (p < 0.001), body fat (%) (p < 0.001), and free fatty acid (p = 0.007) in the Korean diet group decreased significantly after the dietary intervention compared to the control group. The amount of intake of rice, whole grains, green vegetables, Kimchi, and soybean fermented food were increased significantly compared to the control group (p < 0.001). The Korean diet group showed significant decreases (p < 0.001) in the intake of animal protein, lipid, and cholesterol derived from animal foods compared to the control group but significant increases (p < 0.001) in the intake of total calories, folic acid, dietary fiber, sodium, potassium, and vitamins A, E, and C. Conclusion: In patients with hypertension and diabetes, it was confirmed that regular eating of a healthy Korean diet helps improve the risk factors for GGT and cardiovascular diseases.

• Journal of Korean Academy of Nursing
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• v.1 no.1
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• pp.64-76
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• 1970

This report will present a clinical and statistical analysis of 210 case of Ectopic pregnancies who were treated at the Department of Obstetrics and Gynecology at Chung Nam Medical Center from January, 1966 to March, 1970. The results obtained are as follows; 1. The total number of Ectopic pregnancies was 8.22%. 2. The occurrence of Ectopic pregnancy was high in June(13.81%), low in October(2.98%). There was a higher occurrence of Ectopic pregnancy in the summer than in the winter. 3. The average age of all patients was 33.25 years. The most frequent age for this type of pregnancy was 31-35 years (32.86%) . The youngest patient was 18 years old and the oldest was 50. 4. Multipara occurred in 82.38% of the cases; Mulipara in 17. 62% and the occurrence of primipara was especially high, 20.95%. 5. 48.09% of the women had previously experienced normal deliveries; 42.8% had received artificial abortions and 5.23% had experienced spontaneous abortions. 3.8% had a previous history of Ectopic pregnancy. It was found that the occurrence of Ectopic pregnancy was more frequent in those women who had a D & C in the Past. 6. The average length of infertility was 21.7 months. The shortest length was 60 days; longest period of infertility was 19 years. 7. The occurrence of Ectopic pregnancy is higher (29.27%) in patient who have experienced only one previous D & C. The total number of patients who received a D & C was 58.57%. 3. Ectopic symptoms appeared during the first 4.7 weeks (mean) and most frequently occurred between the 5th and 6th weeks (48.57%) of pregnancy. The Symptoms were: -99.04% complained of lower abdominal pains. -80.95% experienced abnormal uttering bleeding. -42.38% experienced bleeding before the occurrence of pain. -18.57% experienced pain before the occurrence of bleeding. -8.57% experienced both pain and bleeding. -7.62% experienced only bleeding. -22.86% experienced only pain. 9. In-77.62% of the cases the annexal mass palpated. 91.42% complained of abdominal tenderness. 42.38% complained of pain when the cervix was examined. 10. Culdocentesis was performed in 86.19% of the cases. In 92.82% of the cases the presence of an Ectopic pregnancy was accurately diagnosed 11. 71.90% of the Ectopic pregnancies occurred in the ampule portion of the ovarian tube, of the total number of gestations, 40.95% were tubal abortions and 59.05% were ruptured. The ruptured group occurred more frequently in the islamic portion and interstitial portion of the tube than the aborted group. The aborted group occurred more frequently in the fimbrial extremities of the tube. 12. The blood pressure (systolic) was noted at 119-80mmHg in 81.89% of the total cases. Hemoglobin value was noted at over 8gm/㎗ in 58.57% of the cases. The average blood transfusion was 2.3 pints. 13. In 52.86% of the Ectopic pregnancies the right side of the ovarian tube was affected. The left side of the tube was affected in 47.14% of the cases. 14. 3.33% of the patients were not given an accurate diagnosis. 15. The kinds of operation performed were as follows; Salpingectomy, 41.43%; Adnectomy, 38.57% and Adnectomy with total hysterectomy, 19.05%. 16. The patient mortality rate was significantly small; only 1 case out of 210 died. This patient most likely had a profuse hemorrhage because of a ruptured tube before her admission to the hospital. 17. The patients personal feelings and attitudes must be treated with care. Particularly patients who are concerned about vaginal bleeding or the impossibility of another pregnancy.

• The Journal of Engineering Geology
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• v.16 no.1 s.47
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• pp.69-83
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• 2006

This study aims to evaluate a complex groundwater flow system around the underground oil storage caverns using the concept of hydraulic compartment. For the hydrogeological analysis, the hydraulic testing data, the evolution of groundwater levels in 28 surface monitoring boreholes and pressure variation of 95 horizontal and 63 vertical water curtain holes in the caverns were utilized. At the cavern level, the Hydraulic Conductor Domains(fracture zones) are characterized one local major fracture zone(NE-1)and two local fracture zones between the FZ-1 and FZ-2 fracture zones. The Hydraulic Rock Domain(rock mass) is divided into four compartments by the above local fracture zones. Two Hydraulic Rock Domains(A, B) around the FZ-2 zone have a relatively high initial groundwater pressures up to $15kg/cm^2$ and the differences between the upper and lower groundwater levels, measured from the monitoring holes equipped with double completion, are in the range of 10 and 40 m throughout the construction stage, indicating relatively good hydraulic connection between the near surface and bedrock groundwater systems. On the other hand, two Hydraulic Rock Domains(C, D) adjacent to the FZ-1, the groundwater levels in the upper and lower zones are shown a great difference in the maximum of 120 m and the high water levels in the upper groundwater system were not varied during the construction stage. This might be resulted from the very low hydraulic conductivity$(7.2X10^{-10}m/sec)$ in the zone, six times lower than that of Domain C, D. Groundwater recharge rates obtained from the numerical modeling are 2% of the annual mean precipitation(1,356mm/year) for 20 years.

• Journal of Environmental Science International
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• v.3 no.3
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• pp.273-284
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• 1994

The primary objective of this study was to examine the toxic effects of PCP on activated sludge and to analyze its metabolic responses while treating wastewater containing pentachlorophenol (PCP) in a sequencing batch reactor (SBR) system operating under different control strategies. This study was conducted in two phases 1 and 2 (8-hr and 12-hr cycles). Each phase was operated with two control strategies I and II. Strategy I (reactor 1) involved rapid addition (5 minutes to complete) of substrate to the reactor with continuous mixing but no aeration for 2 hours. Strategy ll (reactor 2) involved adding the feed continuously during the first 2 hours of the cycle when the system was mixed but not aerated. During both phases each reactor was operated at a sludge age of 15 days. The synthetic wastewater was used as a feed. The COD of the feed solution was about 380 mg/l. After the reference response for both reactors was established, the steady state response of each system was established for PCP feed concentrations of 0.1 mg/l, 1.0 mg/l, and 5.0 mg/l in SBR systems operating on both 8-hr and 12-hr cycles. Soluble COD removal was not inhibited at any feed PCP concentrations used. At 5.0 mg/l fined PCP concentration and in SBR systems operating on phase 2, the concentrations of MLVSS were decreased; selective pressure on the mixed biomass might be increased, narrowing the range of possible ecological responses; the settleability of activated sludge was poor; the SOURS were increased, showing that the systems were shocked. Nitrification was made to some extent at all concentrations of feed PCP in SBR systems operating on phase 2 whereas in SBR systems operating on phase 1 little nitrification was observed. Then, nitrification will be delayed as much as soluble COD removal is retarded due to PCP inhibition effects. Enhanced biological phosphorus removal occurring in the system operating with control strategy I during phase 1 of this work and in the presence of low concentrations of PCP was unreliable and might cease at anytime, whereas enhanced biological phosphorus removal occurring in the system operating with either control strategy I or II during phase 2 of this work and in the Presence of feed PCP concentrations up to 1.0 mg/l was reliable. When, however, such processes were exposed to 5.0 mg/l PCP dose, enhanced phosphorus removal ceased and never returned.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.1
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• pp.68-75
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• 2013

The physiological properties of water extracts from Jerusalem artichoke (Helianthus tuberosus L.) leaves (JAL) with different extraction processes (stirrer extraction, SE; reflux extraction, RE; autoclave extraction, AE; low temperature high pressure extraction, LTPE) were investigated. The freeze-dried powder yields of SE, RE, AE, and LTPE were 22.33%, 29.88%, 31.65, and 15.74%, respectively. AE showed the highest value of extract yield. The $a^*$ and $b^*$ values were higher in AE compared to other extracts. Total polyphenolics and flavonoids contents in AE was significantly higher than in other extracts. The amount of proanthocyanidin related substances were highest in LTPE (29.36 mg/g), followed by RE (21.57 mg/g), SE (20.35 mg/g), and AE (13.02 mg/g). The electron donating abilities of SE, RE, AE, and LTPE at a concentration of $500{\mu}g/mL$ (w/v) were 76.16%, 39.55%, 25.50%, and 12.59%, respectively. Reducing power for the four different processes was 1.79, 1.60, 1.51, and 1.17, respectively. Additionally the same tendency was observed with electron donating ability and reducing power for ABTS radical and nitrite scavenging abilities. AE and LTPE showed relatively high antioxidant activities. Alpha-glucosidase, xanthine oxidase, and angiotensin I-converting enzyme inhibitory activities of LTPE at a concentration of $500{\mu}g/mL$ (w/v) were somewhat higher than other extracts. Additionally, there was significantly higher or little lower inhibitory activity compared to the control group. In conclusion, we provided experimental evidence that extracts of JAL have potential as functional materials, and component analysis of JAL could be used as new cosmeceuticals. Also, LTPE is the superior method for the enhancement of biological activity.

• The Journal of the Korean Society for Microbiology
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• v.15 no.1
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• pp.19-32
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• 1980

Besides the benefits of antimicrobial agents in the control of various infectious diseases, widespread and prolonged use of particular antimicrobial agents has brought about the increase of drug-resistant strains in a community and the profound changes in the pattern of infectious diseases. In Korea, there are some remote villages where no clinics and drug stores are available and the residents in those areas are assumed to have fewer chances to contact with antimicrobial agents. In the present study, the differences in susceptibilities to 14 antimicrobial agents between the isolates from rural areas(R) and Seoul National University Hospital(SNUH, H) were studied. The isolates and their numbers were Staphylococcus aureus, R;55, H;68), Enterococci(R;28, H;30), Escherichia coli(R;40, H;40), Enterobacter aerogenes(R;25, H;21) and Klebsiella pneunoniae(R;58, H;67). Minimal inhibitory concentrations(MIC's) of penicillin, ampicillin, carbenicillin, cephalexin, tetracycline, oxytetracyline, doxycycline, minocycline, gentamicin, kanamycin, streptomycin, erythromycin, troleandomycin and co-trimoxazole were determined by agar dilution method. I. Comparison of MIC's and resistant strain proportions between isolates from SNUH and rural areas. MIC's and/or resistant strain proportions of the isolates from SNUH were significantly higher than those of the isolates from rural areas in the cases of 1. S. aureus to doxycycline, streptomycin and kanamycin. 2. E. coli to penicillin, ampicillin, carbenicillin, tetracycline, oxytetracycline, doxycycline, minocycline, streptomycin, kanamycin, erythromycin and co-trimoxazole. 3. E. aerogences to carbenicillin, tetracycline, oxytetracycline, doxycycline, minocycline, streptomycin, kanamycin, genaamicin and co-trimoxazole. 4. K pneunoniae to penicillin, ampicillin, tetracycline, oxytetracycline, doxycycline, monocycline, streptomycin, kanamycine, gentamicin and co-trimoxazole. However, the mean MIC and resistant strain proportion of S. aureus to tetracycline were higher in isolates from rural areas than in those from SNUH and Enterococci showed no differences in susceptibilities to the antimicrobial agents between isolates from rural areas and from SNUH. Therefore, in general, differenes in susceptibility to these antimicrobial agents between the isolates from rural areas and SNUH were remarkably greater and broader in gram negative enteric bacteria. II. Multiple drug resistance pattern. Patterns and incidences of multiple drug resistance were studied with penicillin, ampicillin, tetracycline, cephalexin, gentamicin, streptomcin, kanamycin and co-trimoxazole in Enterococci, E. coli, E. aeroges and K. pneumoniae. There appeared significant differences in the incidence of multiply drug-resistant strains and multiple drug resistance patterns between the isolates from SNUH and rural areas in Enterococci, E. coli, E. aerogenes and K. pneumoniae. However, there was no difference in the incidence of multiply drug-resistant strains between isolates of S. aureus from SNUH and rural areas but the pattern of multiple resistance of the SNUH strains of S. aureus was diverse, while that of the rural strains was predominantly confined to penicillin-tetracycline combination. The incidence of multigly drug-resistant strains and diversity of their patterns were the highest in E. coli strains isolated from SNUH and there were no multiply drug resistant strrains in Enterococci and K. pneumoniae strains isolated from rural areas. The number of drug-resistance determinants was also different between the isolates from rural areas and SNUH. Most of the multiply drug-resistant strains of E. coli, E. aerogenes and K. pneumoniae isolated from SNUH were resistant to more than 3 kinds of antimicrobial agents, most frequently to ampicillin, tetracycline and streptomycin, while multiply drug-resistant strains from rural areas were resistant to 2 kinds of antimicrobial agents among ampicillin, tetracycline and streptomycin. With drug-resistant E. coli strains, resistance to tetracycline which was used most widely since 1951 was most frequently involved as a part of mutliple drug-resistance, followed by resistance to ampicillin and streptomycin. This strongly suggests that emergence of drug-restant strains in a community is directly dependent on the selective pressure exerted by the antimicrobial agent used. III. Cross resistance. Cross resistance of bacteria was studied among tetracycline penicillin, aminoglycoside and macrolide derivatives by analyzing correlation coefficients of sucseptibilities using the least square method. In this study, there were high correlations among the susceptibilities to related derivatives. It appears that the relatively low correlations in susceptibilities present in some cases are due to intrinsic resistance of E. aerogenes to penicillin, Enterococci to aminoglycoside and E. coli E. aerogenes and K. pneumoniae to macrolide derivatives.