• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.1
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• pp.92-105
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• 2019

Spatial and temporal characteristics of phytoplankton communities around the coastal waters of Jeju Island were investigated with environmental factors such as water temperature, salinity, and dissolved oxygen. Monthly samples were collected at 0 and 30 m depths of 10 stations from March 2015 to February 2016. During the survey period, water temperature ranged in 13.7~25.9 and $13.6{\sim}20.8^{\circ}C$ at 0 and 30 m, salinity in 31.51~34.47 and 33.03~34.47 psu at 0 and 30 m, and dissolved oxygen in 6.12~8.10 and $5.73{\sim}7.88mg\;L^{-1}$ at 0 and 30 m, respectively. Chlorophyll-a ranged in 0.28~2.48 and $0.44{\sim}1.01{\mu}g\;L^{-1}$ at 0 and 30 m, respectively. Phytoplankton abundance fluctuated in the range of $5,300{\sim}639,900cells\;L^{-1}$ during the year, showing the lowest in February at all stations, and the highest in July at the northern and western sea as well as in August at the southern and eastern sea of Jeju Island. A total of 362 species were occurred including 181 spp. of Bacillariophyta, 147 spp. of Dinophyta and 34 spp. of other phytoflagellates. Dominant species with occupancy rate over 20 percent of phytoplankton abundance showed apparent seasonal succession such as Paralia sulcata and Skeletonema costatum in spring and autumn, 6 spp. of genus Chaetoceros in summer, and 2 spp. of genus Chaetoceros and Thalassionema frauenfeldii in winter. Monthly abundance in the northern and western sea fluctuated with similar tendency, and the southern and eastern sea also showed similar pattern of monthly abundance variation. Species composition and dominant species succession mentioned above were quite different from previous studies, so some physical changes such as water temperature, salinity and current pattern might cause the changes of phytoplankton assemblages around Jeju Island.

• Journal of Intelligence and Information Systems
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• v.25 no.4
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• pp.123-139
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• 2019

The job classification system of major job sites differs from site to site and is different from the job classification system of the 'SQF(Sectoral Qualifications Framework)' proposed by the SW field. Therefore, a new job classification system is needed for SW companies, SW job seekers, and job sites to understand. The purpose of this study is to establish a standard job classification system that reflects market demand by analyzing SQF based on job offer information of major job sites and the NCS(National Competency Standards). For this purpose, the association analysis between occupations of major job sites is conducted and the association rule between SQF and occupation is conducted to derive the association rule between occupations. Using this association rule, we proposed an intelligent job classification system based on data mapping the job classification system of major job sites and SQF and job classification system. First, major job sites are selected to obtain information on the job classification system of the SW market. Then We identify ways to collect job information from each site and collect data through open API. Focusing on the relationship between the data, filtering only the job information posted on each job site at the same time, other job information is deleted. Next, we will map the job classification system between job sites using the association rules derived from the association analysis. We will complete the mapping between these market segments, discuss with the experts, further map the SQF, and finally propose a new job classification system. As a result, more than 30,000 job listings were collected in XML format using open API in 'WORKNET,' 'JOBKOREA,' and 'saramin', which are the main job sites in Korea. After filtering out about 900 job postings simultaneously posted on multiple job sites, 800 association rules were derived by applying the Apriori algorithm, which is a frequent pattern mining. Based on 800 related rules, the job classification system of WORKNET, JOBKOREA, and saramin and the SQF job classification system were mapped and classified into 1st and 4th stages. In the new job taxonomy, the first primary class, IT consulting, computer system, network, and security related job system, consisted of three secondary classifications, five tertiary classifications, and five fourth classifications. The second primary classification, the database and the job system related to system operation, consisted of three secondary classifications, three tertiary classifications, and four fourth classifications. The third primary category, Web Planning, Web Programming, Web Design, and Game, was composed of four secondary classifications, nine tertiary classifications, and two fourth classifications. The last primary classification, job systems related to ICT management, computer and communication engineering technology, consisted of three secondary classifications and six tertiary classifications. In particular, the new job classification system has a relatively flexible stage of classification, unlike other existing classification systems. WORKNET divides jobs into third categories, JOBKOREA divides jobs into second categories, and the subdivided jobs into keywords. saramin divided the job into the second classification, and the subdivided the job into keyword form. The newly proposed standard job classification system accepts some keyword-based jobs, and treats some product names as jobs. In the classification system, not only are jobs suspended in the second classification, but there are also jobs that are subdivided into the fourth classification. This reflected the idea that not all jobs could be broken down into the same steps. We also proposed a combination of rules and experts' opinions from market data collected and conducted associative analysis. Therefore, the newly proposed job classification system can be regarded as a data-based intelligent job classification system that reflects the market demand, unlike the existing job classification system. This study is meaningful in that it suggests a new job classification system that reflects market demand by attempting mapping between occupations based on data through the association analysis between occupations rather than intuition of some experts. However, this study has a limitation in that it cannot fully reflect the market demand that changes over time because the data collection point is temporary. As market demands change over time, including seasonal factors and major corporate public recruitment timings, continuous data monitoring and repeated experiments are needed to achieve more accurate matching. The results of this study can be used to suggest the direction of improvement of SQF in the SW industry in the future, and it is expected to be transferred to other industries with the experience of success in the SW industry.

• Journal of Nutrition and Health
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• v.8 no.1
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• pp.15-37
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• 1975

I. Subject of the study A study on the nutritive value and utilization of powdered seaweeds. II. Purpose and Importance of the study A. In Korea the shortage of food will be inevitable by the rapidly growing population. It will be very important study to develop a new food from the seaweeds which were not used hitherto for human consumption. B. The several kinds of seaweeds have been used by man in Korea mainly as side-dishes. However, a properly powdered seaweed will enable itself to be a good supplement or mixture to certain cereal flours. C. By adding the powdered seaweed to any cereals which have long been staple foods in this country the two fold benefits; saving of cereals and change of dietary pattern, will be secured. III. Objects and scope of the study A. Objects of the study The objects will come under four items. 1. To develop a powdered seaweed as a new food from the seaweeds which have been not used for human consumption. 2. To evaluate the nutritional quality of the products the analysis for chemical composition and animal feeding experiment will be conducted. 3. Experimental cocking and accepability test will be conducted for the powdered products to evaluate the value as food stuff. 4. Sanitary test and also economical analysis will be conducted for the powdered products. B. Scope of the study 1. Production of seaweed powders Sargassum fulvellum growing in eastern coast and Sargassum patens C.A. in southern coast were used as the material for the powders. These algae, which have been not used for human consumption, were pulverized through the processes of washing, drying, pulverization, etc. 2. Nutritional experiments a. Chemical composition Proximate components (water, protein, fat, cellulose, sugar, ash, salt), minerals (calcium, phosphorus, iron, iodine), vitamins (A, $B_1,\;B_2$ niacin, C) and amino acids were analyzed for the seaweed powders. b. Animal feeding experiment Weaning 160 rats (80 male and 80 female rats) were used as experimental animals, dividing them into 16 groups, 10 rats each group. Each group was fed for 12 weeks on cereal diet (Wheat flour, rice powder, barley powder, potato powder, corn flour) with the supplementary levels of 5%, 10%, 15%, 20% and 30% of the seaweed powder. After the feeding the growth, feed efficiency ratio, protain efficiency ratio and ,organs weights were checked and urine analysis, feces analysis and serum analysis were also conducted. 3. Experimental cooking and acceptability test a. Several basic studies were conducted to find the characteristics of the seaweed powder. b. 17 kinds of Korean dishes and 9 kinds of foreign dishes were prepared with cereal flours (wheat, rice, barley, potato, corn) with the supplementary levels of 5%, 10%, 15%, 20% and 30% of the seaweed powder. c. Acceptability test for the dishes was conducted according to plank's Form. 4. Sanitary test The heavy metals (Cd, Pb, As, Hg) in the seaweed powders were determined. 5. Economical analysis The retail price of the seaweed powder was compared with those of other cereals in the market. And also economical analysis was made from the nutritional point of view, calculating the body weight gained in grams per unit price of each feeding diet. IV. Results of the study and the suggestion for application A. Chemical composition 1. There is no any big difference in proximate components between powders of Sargassum fulvellum in eastern coast and Sargassum patens C.A. in southern coast. Seasonal difference is also not significant. Higher levels of protein, cellulose, ash and salt were found in the powders compared with common cereal foods. 2. The levels of calcium (Ca) and iron (Fe) in the powders were significantly higher than common cereal foods and also rich in iodine (I). Existence of vitamin A and vitamin C in the Powders is different point from cereal foods. Vitamin $B_1\;and\;B_2$ are also relatively rich in the powders.'Vitamin A in ·Sargassum fulvellum is high and the levels of some minerals and vitamins are seemed4 to be some influenced by seasons. 3. In the amino acid composition methionine, isoleucine, Iysine and valine are limiting amino acids. The protein qualities of Sargassum fulvellum and Sargassum patens C.A. are seemed to be .almost same and generally ·good. Seasonal difference in amino acid composition was found. B. Animal feeding experiment 1. The best growth was found at.10% supplemental level of the seaweed Powder and lower growth rate was shown at 30% level. 2. It was shown that 15% supplemental level of the Seaweed powder seems to fulfil, to some extent the mineral requirement of the animals. 3. No any changes were found in organs development except that, in kidney, there found decreasing in weight by increasing the supplemental level of the seaweed powder. 4. There is no any significant changes in nitrogen retention, serum cholesterol, serum calcium and urinary calcium in each supplemental level of the seaweed powder. 5. In animal feeding experiment it was concluded that $5%{\sim}15%$ levels supplementation of the seaweed powder are possible. C. Experimental cooking and acceptability test 1. The seaweed powder showed to be utilized more excellently in foreign cookings than in Korean cookings. Higher supplemental level of seaweed was passible in foreign cookings. 2. Hae-Jo-Kang and Jeon-Byung were more excellent than Song-Pyun, wheat cake, Soo-Je-Bee and wheat noodle. Hae-Je-Kang was excellent in its quality even as high as 5% supplemental level. 3. The higher levels of supplementation were used the more sticky cooking products were obtained. Song-Pyun and wheat cake were palatable and lustrous in 2% supplementation level. 4. In drop cookie the higher levels of supplementation, the more crisp product was obtained, compared with other cookies. 5. Corn cake, thin rice gruel, rice gruel and potato Jeon-Byung were more excellent in their quality than potato Man-Doo and potato noodle. Corn cake, thin rice gruel and rice gruel were excellent even as high as 5% supplementation level. 6. In several cooking Porducts some seaweed-oder was perceived in case of 3% or more levels of supplementation. This may be much diminished by the use of proper condiments. D. Sanitary test It seems that there is no any heavy metals (Cd, Pb, As, Hg) problem in these seaweed Powders in case these Powders are used as supplements to any cereal flours E. Economical analysis The price of the seaweed powder is lower than those of other cereals and that may be more lowered when mass production of the seaweed powder is made in future. The supplement of the seaweed powder to any cereals is also economical with the criterion of animal growth rate. F. It is recommended that these seaweed powders should be developed and used as supplement to any cereal flours or used as other food material. By doing so, both saving of cereals and improvement of individual's nutrition will greatly be achieved. It is also recommended that the feeding experiment for men would be conducted in future.

• Journal of Korean Society of Forest Science
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• v.82 no.2
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• pp.152-165
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• 1993

This is the basic study in order to know the amount of transpirational water loss in a Larix leptorepis stand by a heat pulse method. Especially this study has been measured and discussed the diurnal and seasonal trends of heat pulse velocity by changes of radiation, temperature and humidity, differences of heat pulse velocity by direction and depth in stem, differences of heat pulse velocity by dominant, codominant and suppressed trees, diurnal change of heat pulse velocity by change of leaf water potential, sap flow path way in sapwood by dye penetration and amount of daily and annual transpiration in a tree and stand. The results obtained as follows : 1. Relation between heat pulse velocity(V) and sap flow rate(SFR) was established as a equation of SFR=1.37V($r=0.96^{**}$). 2. The sap flow rate presented in the order of dominant, codominant and suppressed tree, respectively. The daily heat pulse velocity was changed by radiation, temperature and vapor pressure deficit. 3. The heat pulse velocity in individual trees did not differ in early morning and in late night, but had some differed from 12 to 16 hours when radiation was relatively high. 4. The heat pulse velocity and leaf water potential showed similar diurnal variation. 5. The seasonal variation of heat pulse velocity was highest in August, but lowest in October and similar value of heat pulse velocity in the other months. 6. The heat pulse velocity in stem by direction was highest in eastern, but lowest in southern and similar velocity in western and northern. 7. The difference of heat pulse velocity in according to depths was highest in 2.0cm depth, medium in 1.0cm depth, and lowest in 3.0cm depth from surface of stem. 8. The sap flow path way in stem showed spiral ascent turning right pattern in five sample trees, especially showed little spiral ascent turning right in lower part than 3m hight above ground, but very speedy in higher than 3m hight. 9. The amount of sap flow(SF) was presented as a equation of SF=1.37AV and especially SF in dominant tree was larger than in codominant or suppressed tree. 10. The amount of daily transpiration was 30.8ton/ha/day and its composition ratio was 83% at day and 17% at night. 11. The amount of stand transpiration per month was largest in August(1,194ton/ha/month), lowest in May (386ton/ha/month). The amount of stand transpiration per year was 3,983ton/ha/year.

• Korean Journal of Environmental Biology
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• v.26 no.4
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• pp.279-291
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• 2008

The seasonal distribution pattern of the Bivalvia samples collected from 12 stations in Gamak Bay in April, July, September and November from 2001 to 2006. A total of 28 species (226.72$\pm$196.20 ind. m$^{-2}$) were identified. The COD has decreased from 3.30 mg L$^{-1}$ to 1.89 mg L$^{-1}$ level on average and especially, the COD of sediment has decreased from 21.51 mg g-dry$^{-1}$ to 16.99 mg g-dry$^{-1}$ level on average. Therefore, water quality level of Gamak Bay was improved from level 3 to 2. The dominant species over 1.0 percentages were composed of the total 13 species, and they occupied 96.75% of the total density of the Bivalvia. Major dominant species was Musculista senhousia 100.38 ind. m$^{-2}$ (22.16%), Moerella rutila 69.00 ind. m$^{-2}$ (15.23%), Theorafragilis 49.70 ind. m$^{-2}$ (10.97%), Mytilus edulis 42.18 ind. m$^{-2}$ (9.31 %), and Raphia undulata 40.99 ind. m$^{-2}$ (9.05%). This area could be divided into three groups by the cluster analysis based on the total species composition.

• Economic and Environmental Geology
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• v.45 no.3
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• pp.277-294
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• 2012

The characteristics of temporal spacial radon variation in soil according to parent rock type and affecting factors were studied in Busan, Korea. The concentration of $^{222}Rn$ in soils and their parent elements ($^{226}Ra$,$^{228}Ra$, U and Th) in rocks and soils were measured at 24 sites in Busan area. The distribution and transportation behavior of these parent elements were analyzed and their correlations to radon concentration in soil were determined. Topographic effects were also evaluated. Two in-situ radon measurement (soil probe and buried tube) methods were applied to measure radon concentration in soil and their accuracies were evaluated. The spatial variation of radon in soil generally reflected U concentration in the parent rock. Average radon concentrations were higher in plutonic rocks than in volcanic rocks and were decreased in the order of felsic>intermediate>mafic rock. However, the radon concentrations were significantly varied in soils developed from same parent rocks due to the disequilibrium of U and $^{226}Ra$ between rock and soil. As results, the correlation of these element concentrations between rocks and soils was very low and radon concentrations in soils had highly co-related to the concentrations of these elements in soils. Th and $^{228}Ra$ show complex enrichment characteristics, differing significantly with U, in soils developed from same parent rock because the geochemical behavior of these elements during weathering and soil developing process was different with U. The radon concentrations in the same depth of soil in slope area were also different according to positions. The radon concentrations in soils developed from same parent rocks (19 sites at Pusan National University) varied 6.8~29.8Bq/L range because of small scale topographic variation. The opposite seasonal variation pattern of radon were observed according to soil properties. It was determined that buried tube method is more accurate method than soil probe method and was very advantageous application for the analysis for the characteristics of temporal spacial radon variation in soil.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.4
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• pp.396-402
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• 2014

The spring season in Korea features a dynamic landscape with a variety of flowers such as magnolias, azaleas, forsythias, cherry blossoms and royal azaleas flowering sequentially one after another. However, the narrowing of south-north differences in flowering dates and those among the flower species was observed in 2014, taking a toll on economic and shared communal values of seasonal landscape. This study was carried out to determine whether the 2014 incidence is an outlier or a mega trend in spring phenology. Data on flowering dates of forsythias and cherry blossoms, two typical spring flower species, as observed for the recent 60 years in 6 weather stations of Korea Meteorological Administration (KMA) indicate that the difference spanning the flowering date of forsythias, the flower blooming earlier in spring, and that of cherry blossoms that flower later than forsythias was 30 days at the longest and 14 days on an average in the climatological normal year for the period 1951-1980, comparing with the period 1981-2010 when the difference narrowed to 21 days at the longest and 11 days on an average. The year 2014 in particular saw the gap further narrowing down to 7 days, making it possible to see forsythias and cherry blossoms blooming at the same time in the same location. 'Cherry blossom front' took 20 days in traveling from Busan, the earliest flowering station, to Incheon, the latest flowering station, in the case of the 1951-1980 normal year, while 16 days for the 1981-2010 and 6 days for 2014 were observed. The delay in flowering date of forsythias for each time period was 20, 17, and 12 days, respectively. It is presumed that the recent climate change pattern in the Korean Peninsula as indicated by rapid temperature hikes in late spring contrastive to slow temperature rise in early spring immediately after dormancy release brought forward the flowering date of cherry blossoms which comes later than forsythias which flowers early in spring. Thermal time based heating requirements for flowering of 2 species were estimated by analyzing the 60 year data at the 6 locations and used to predict flowering date in 2014. The root mean square error for the prediction was within 2 days from the observed flowering dates in both species at all 6 locations, showing a feasibility of thermal time as a prognostic tool.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.22 no.4
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• pp.151-171
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• 2017

Most of oceanic current maps in the secondary school science and earth science textbooks have been made on the base of extensive in-situ measurements conducted by Japanese oceanographers during 1930s. According to up-to-date scientific knowledge on the currents in the Yellow Sea and the East China Sea (YES), such maps have significant errors and are likely to cause misconceptions to students, thus new schematic map of ocean currents is needed. The currents in the YES change seasonally due to relatively shallow water depths, complex terrain, winds, and tides. These factors make it difficult to construct a unified ocean current map of the YES. Sixteen major items, such as the flow of the Kuroshio Current into the East China Sea and its northward path, the origin of the Tsushima Warm Current and its path into the Korea Strait, the path of Taiwan Warm Current, the Jeju Warm Current, the runoff pattern of the Yangtze River flow, the routes of the northward Yellow Sea Warm Current, the Chinese Coastal Current, and the West Korea Coastal Current off the west coast of the Korean Peninsula, were selected to produce the schematic current map. Review of previous scientific researches, in-depth discussions through academic conferences, expert discussions, and consultations for three years since 2014 enabled us to produce the final ocean current maps for the YES after many revisions. Considering the complexity of the ocean currents, we made seven ocean current maps: two representative current patterns in summer and winter, seasonal current maps for upper layer and lower layer in summer and winter, and one representative surface current map. It is expected that the representative maps of the YES, connected to the current maps of the East Sea and the Northwest Pacific Ocean, would be widely utilized for diverse purposes in the secondary-school textbooks as well as high-level educational purposes and even for scientific scholarly experts.

• Journal of Animal Environmental Science
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• v.11 no.3
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• pp.197-206
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• 2005

This study was carried out to investigate the concentration and characteristics of dust originating from windowless broiler building in each season. 12.0m width and 46m tenth with side wall height of 3.0m was investigated and capacity was 12,800 birds at a stock density of 23.2 birds per square meter. Dust concentrations in terms of total suspended particles (TSP), and particulate matter of sizes $10{\mu}m(PM10),\;2.5{\mu}m (PM2.5),\;and\;1{\mu}m(PM1)$ were measured at 30-minute intervals. On the basis of broiler age, the average dust concentration in summer in TSP as follows: 1,229 904.5 558.8 and $1,053{\mu}g/m^3$ on the broilers' first to fourth week of age, respectively. But during winter, the average dust concentration showed an increasing pattern, as follows: 465.4, 1,401, 4,497, 5,097 and $6,873{\mu}g/m^3$ on the broilers' first to fifth week of age, respectively. The maximum dust concentration of $11,132{\mu}g/m^3$ was observed on the fifth week. On a daily basis, the maximum dust concentration during summer was detected in early morning, and the minimum in the afternoon. The aerial dust particle size of $0.05\~0.35{\mu}m$ was the highest in number. But on volume basis, particle size of 16~99 un had the largest percentage in the broiler house. Crude protein of the dust $(42.8\~65.2\%)$, on dry matter basis, was higher than that $(20.5\~24.5\%)$ fed to the broilers. Heavy metal concentration of the dust also had high levels compared with that of the feed.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.3
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• pp.206-211
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• 1984

The influence of fertilizer on the growth characteristics in Korean lawn grass was studied from June through October in a experiment. The results were as follows: 1. Maximum dry matter weight of Korean lawn grass was achieved in early in early August when it was $64.3g/m^2$ without fertilizer and $157.9g/m^2$ with fertilizer. On the other hand, the dry matter weight of whole plant including Korean lawn grass reached the maximum in late September, which was late, to some extent, compared with that if pure Korean lawn grass, presumably associated with seed maturing period of $C_4$ type plants. 2. Notable positive effect on leaf blade and non-leaf part weight in Korean lawn grass was also detected. However, the rate of dry matter occupied by non-leaf part was markedly increased by fertilizer application. 3. The dry matter portion occupied by Korean lawn grass the in total dry matter weight of whole plant was significantly decreased as time went by, particularly in case of fertilizer application. 4. Fertilizer, which might imply an increased potential of tiller numbers according to fertilizer. 5. In general, the seasonal change pattern of the rhizome of Korean lawn grass coincided with that of the aboveground organs: Its maximum dry matter weight achieved from late August to early September was $194.2g/m^2$ with nil fertilizer, and, with fertilizer, $259.7g/m^2$, of which figures were equivalent to be increased to 33.7%, compared to that with nil fertilizer. Applying fertilizer increased the weight of root: The highest values were $36.7g/m^2$ with nil fertilizer and $80.9g/m^2$ with fertilizer.