• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2006.06b
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• pp.289-299
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• 2006

This paper aims to provide strategies to attract container cargoes for the Incheon port by analysing O/D of the container cargoes with the year-2004 export and import data from. The Korean customs service. O/D analysis was carried out with establishing optimal zones, which are defined as City, Gun, Gu(Korean administrative districts) to which the export-import service can be provided from a certain port with minimized freight(or transport) cost and stevedoring fee. For the Incheon port, 35 administrative districts including Seoul and Incheon in Kyunggi-Do and Kangwon-Do are recognized as the optimal zones, and approximately 25.50% of around 2.02-million-TEU per year of the cargoes from the woes are exported and imported through the pan. The strategies to attract container cargoes was suggested by comparing the Incheon port to supposed-competitive pons. The Busan portn(64.89%), Guangyang port(4.46%) and Pyeongtaeck port(3.35%) are supposed as the competitive pons which have a large proportion of handling the cargoes from the optimal zones. When comparing the Incheon port to these ports, The Incheon pan requires a distinctive cost strategy, providing incentives to attract shipping companies and cargoes, improving efficiency related to loading-unloading at the port, and reinforcing Feeder-Network and advertisements about cost-saving to the shippers(the owners of goods) in the national capital region. Consequently, the mentioned requirements are suggested as the strategies to attract cargoes for the Incheon port.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.2
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• pp.89-97
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• 1983

This experiment was carried out in order to study the effect of seasonal changes and location differences on the productivity of the native reed (Phragmites Communis Trinius). The samples of reed were taken at about 30-days interval from May to October, 1982, on the open field of the reclaimed land, the river bank and the tideland in Chonnam area, and measured the yield, the feed compositions and in vitro dry-matter digestibility(IVD). The results are summarized as follow: 1. Plant height was rapidly heightened in May and June, and the number of leaves rapidly increased from May to August. However, dry matter yield increased until September and gradually decreased thereafter. 2. In general, the content of crude protein and the in vitro dry matter digestibility decreased with ageing, and the content of fiber increased. 3. Considerable difference by location in the chemical composition including $SiO_2$, Ca and P was observed. 4. There was a significant negative correlation (p<0.05) between the content of crude protein and that of crude fiber. There was a significant positive correlation(p<0.05) between the in vitro dry-matter digestibility(IVD) by two-stage method and the content of crude protein, and also was a significant negative correlation(p<0.05) between the content of fiber and that of crude protein.

• FLOWER RESEARCH JOURNAL
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• v.17 no.2
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• pp.81-87
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• 2009

This study was conducted to examine the characteristics of flowering and fruiting in Nelumbo pentapetala 'Yellow Bird'. Lotus rhizomes were planted in pot (70 cm in length and 71 cm in width) on April 18, 2008, and grown under rain shelter condition at a private farm in Muan-gun, Jeonnam. Ninety percent of the lotus plants were bloomed as two flowers per a plant, and the others were one flower. The first flowers were bloomed in the middle or late July, and the second flowers in the early August. Flower stalks were formed between eighth and tenth internodes in the main rhizome. Nelumbo pentapetala 'Yellow Bird' had light yellow flowers, 12 cm in length and 13 cm in width. Lotus plants of 21.4% were not bloomed, resulting from the insufficient securing of internodes in the main rhizome and the blind. We, therefore, concluded that Nelumbo pentapetala 'Yellow Bird' as a ornamental plant should be grown up to 8 in the node number of main rhizome until mid-July.

• Journal of Korea Port Economic Association
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• v.34 no.4
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• pp.39-52
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• 2018

The Seosan-Daesan Port is a representative trade port in Chungnam, and has the sixth largest total cargo throughput and the third largest oil cargo throughput in Korea. However, research on this port's development is lacking relative to that for Busan Port, Incheon Port, and Gwangyang Port, and no study exists that suggests the direction of the development strategy for Seosan-Daesan Port. This study discusses the future role of Seosan-Daesan Port in preparation for a rapidly changing future and the development strategy that should be established. Using the AHP, a development strategy is provided for Seosan-Daesan Port from short/mid-term and long-term viewpoints for three aspects: operation activation, infrastructure construction, and policy support. Operation activation is chosen as the most significant factor from a short/mid-term viewpoint, whereas infrastructure construction is recognized as important from a long-term viewpoint. Specifically, from a short/mid-term viewpoint, sustainable container cargo attraction, multipurpose dock construction, management pier construction, and opening of international passenger ferry lines are important factors while from the long-term viewpoint, hinterland construction, petrochemical industry cluster construction, automobile industry cluster construction, and management improvement system are important. Establishing action plans for each strategy and a cooperative network for sharing goals and strengthening cooperation is necessary.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.212-220
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• 2022

When it comes to single node leafy stem cuttings of rose (Rosa hybrida), environmental management such as air temperature, relative humidity, and light affect productivity. In order to investigate the effect of air temperature and relative humidity on the cutting success rate and rooted cuttings quality, a transparent airtight box was used to implement a closed system. We have also tried to find out the most effective photoperiod and the number of leaflets in closed system using artificial light (white LED, 104.0 µmol·m^-2·s^-1 photosynthetic photon flux density). The first experiment was conducted for a total of 6 weeks under 4 airtight period conditions. The number of roots and longest root length decreased as the airtight period increased. But there were no significant differences in the survival rate, shooting rate, and rooting rate according to airtight periods. In the second experiment the results indicated that survival and shooting rate were significantly affected by the photoperiod (0/24, 2/22, 4/20, 8/16, and 16/8 h), the number of leaflets (0, 2, and 4 leaflets) of the cuttings and their interaction. The survival rate was the highest in the 16-h day length and 4 leaflets. By considering survival rate and shooting rate with energy efficiency, the 8-h day length and 2 or 4 leaflets were judged to be the most effective.

• Journal of the Korean Geotechnical Society
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• v.25 no.5
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• pp.5-16
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• 2009

Preconsolidation stress is one of the important design parameters in soft soils because the behavior of saturated soft soils changes dramatically at the preconsolidation stress. For the estimation of preconsolidation stress, the global vertical settlement without considering micro strain behavior has been considered. The purpose of this study is to propose and verify a new method called the "shear wave velocity method" for determination of the preconsolidation stress reflecting on particle behavior at the small-strain. In this study, the undisturbed soft soils obtained at Busan, Incheon and Gwangyang in Korea were used. The oedometer cell incoporated with the bender elements is used for the consolidation tests under the $K_0$ condition. The preconsolidation stress determined by the proposed method is compared with that estimated by Casagrande (e-log p'), Sridharan (log (1+e)-log p'), and Onitsuka (In(1+e)-log p') methods. This study suggests that the shear wave velocity method may determine simply the preconsolidation stress with considering the small-strain behavior.

• Journal of the Korean Geographical Society
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• v.28 no.1
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• pp.40-57
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• 1993

This paper aims to show the various aspects of migration in Kwangju merropolitan area, southwestern Korea, for a period of years 1980-1985. Migratory patterns are spatially extensive in countryside around Kwanfju, and due to high accessibility to the metropolitan area urban implosion emerges in the city. In Chonnam province where Kwangju is loca-ted, all cities and counties except for such in-dustrial areas as Yochon, and Kwangyang are experiencing population losses in terms of net migration by survival rate methods. Kwangju is the exceptionally one of in-migration areas in Chonnam, though its central part(Dong-Gu) is also an out-migrated area. Predominantly in-migration urban areas have high proportions of a student age group between 15-19 years, and that reflects the importance of the educational factor in migration analysis. The municipal authorities of Kwangju are planning to block the way of the middle sxhool students who live in the outskirts of Kwangju to entrance to high school in the city. Thant may stir up migrations into Kwangju for the elementary and middle school students, because the city id expected to provide educational opportunities higher and better than remaining Chonnam areas. Population of Kwangju would, therefore, grow as the students migrate into the city. The findings on the residential intra-city movement in selected 5 Dongs indicate that implications of a short-distance movement re noteworthy; neighbour to neighbour, and the nearest stop in the way from the outer Kwangju as well. Trends in a short-distance movement are in accord with Ravensteins's "law of migra-tion". But in casw of the inter-provincial migra-tion to Kwangju, the number of in-migrants from remoter Seoul is more than that from nearer Chonbuk province. Therefore it supports the fact that the movement between capital region and far off local cities overcomes a distance barrier. The temporary mobility for a day has been increased as the standard of living has improved and it reaches a peak on weekend or on con-secutive holidays. The number of temporal movers to Kwangju from capital region and Yongnam area, southeastern Korea has a greatincrease in terms of the frequency of the passengers' mobility, in particular on Myongjol(the ethnic and traditional festival day) in com-parison with on weekdays. By comparison with two largest Myongjols, the number of movers is more on Chusok(The Full Moon festival on lunar August) than on Sol (lunar new year's day). Annual peak point of weekday movers appears in August because of summer vacation. But the lowest one appears in June, which is related to the busy farming season. A patients' move for medical services in on the increase with a change of living conditions. It is especially true in the industrial counties such as Kwangyang and Yochon. By way of conclusion, it should be pointed out that one of the problems we face in survey of migration volume by the survival rate method is that the survival rate somtimes exceeds the value 1.0, in normal states of which should be under 1.0. it may be due to the shortcoming from the census statistics. We should not give therefore too much stress on the importance of migrations or moves as an element of changes in spatial pattern. In cinclusion, the results of the study show some geographic facts as the followings: 1. One of the outstanding phenomena in all types of movement is the seletivity of ages. The most important factors are related to education and employment. 2. Short-distance movement is carried out in accordance with Ravenstein's law, but in case long-distance movement, in-migration from capital region is prominent in spite of remoten-ces. The gravity between large cities such as Kwangju and Seoul, which has a frequent human movenent, causes urban implosion of small cities between those cities. 3. The temporary mobility for a day, in con-trast to that of permanent movement, is more related to transportation, and its volumes and annual variations are a large-scale. 4. Passengers' mobility is high in industrial cities. And the scope of patients' mobility is narrower than passengers'.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.4
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• pp.325-334
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• 2008

The standard prestressed concrete I-girder bridge (PSC I-girder bridge) is one of the most prevalent types for small and medium bridges in Korea. When determining the member forces in a section to assess the safety of girder in this type of bridge, the general practice is to use the simplified practical equations or the live load distribution factors proposed in design standards rather than the precise analysis through the finite element method or so. Meanwhile, the live load distribution factors currently used in Korean design practice are just a reflection of overseas research results or design standards without alterations. Therefore, it is necessary to develop an equation of the live load distribution factors fit for the design conditions of Korea, considering the standardized section of standard PSC I-girder bridges and the design strength of concrete. In this study, to develop an equation of the live load distribution factors, a parametric analysis and sensitivity analysis were carried out on the parameters such as width of bridge, span length, girder spacing, width of traffic lane, etc. As a result, the major variables to determine the size of distribution factors were girder spacing, overhang length and span length in case of external girders. For internal adjacent girders, the determinant factors were girder spacing, overhang length, span length and width of bridge. For internal girders, the factors were girder spacing, width of bridge and span length. Then, an equation of live load distribution factors was developed through the multiple linear regression analysis on the results of parametric analysis. When the actual practice engineers design a bridge with the equation of live load distribution factors developed here, they will determine the design of member forces ensuring the appropriate safety rate more easily. Moreover, in the preliminary design, this model is expected to save much time for the repetitive design to improve the structural efficiency of PSC I-girder bridges.

• Korean Journal of Ichthyology
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• v.2 no.1
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• pp.63-76
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• 1990

Studies on the microdistribution, distributional aspect and affinity of Korean endemic species, SHIRl, Coreoleueiseus splendidus in th southern half of the Korean peninsula were carried out from May, 1966 to November, 1989. This species was found in 14 independent rivers and streamlets of the south Korea ; Yimjin R., Han R., Kum R., Ungchun S., Mangyung S., Dongjin R., Somjin R., Kwangyang East S., Sachun S., Gonyang S., Nakdong R., Samchukosip S., Samhwa S. of Namhae Island and Guchun S. of Geojae Islands, and were not found from Youngsan R., Ansung S. and Sabgyo S. This species was not common and independent comprising less than 25% of the total fish population in all habiting sites. Distributional zone was in the middle or upper streaches of main streams and tributaries. The average slope of distributional zone was 2.6, minimum slope was 0.29 and maximum slope was 5.56. Thirty-three species were found to occur along with this fish and 10 species of them occurred with more than 50% frequency. They were; 20 sp. of Cyprinidae, 5 sp. of Cobitidae, 1 sp. of Salmonidae, 1 sp. of Bagfridae, 1 sp. of Siluridae, 2 sp. of Amblycipitidae, of Serranidae, and 1 sp. of Eleotridae. Some species of fish appeared to have the same ecological position even though they have different distributional zones. These species were as follows; Acheilognathus signifer and A. limbata, Micriophsogobio koreensis and M. yaluensis in Cyprinidae, Cobitis koreensis, C. longicorpus, C. rotundicaudata in Cobitidae, Liobagrus andersoni and L. mediadiposalis in Amblycipitidae.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.327-338
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• 2020

In recent years, the temperature of Korea has been rapidly increasing due to global warming. Over the past 40 years, the temperature of Korea has risen by about 1.26℃ compared to that in the early 1980s. By region, the west region of the Gangwon Province was the highest at 1.76℃ and the Jeonnam Province was the lowest at 0.96℃. As the temperature continues to rise, it is expected that the rice yield will decrease in the future using the current standard cultivation method. As a result of global warming, the periods in which rice cultivation could be possible in regions each year has increased compared those to the past, showing a wide variety from 110 days in Taebaek to 180 days in Busan and Gwangyang. In addition, the transplanting time was delayed by 3-5 days in all regions. The average annual yield of rice showed an increasing trend when we analyzed the average productivities of developed varieties for cooked rice since the 1980s, especially in the early 1990s, which showed a rapid increase in productivity. The relationship between the average temperature at the time of development and the rice yield was divided into the periods before and after 1996. The higher the average temperature, the lower the yield of the developed varieties until 1996. However, since 1996, the increase in the average temperature did not show a trend in the productivity of the developed varieties. The climate change adaptability of developed rice varieties was investigated by analyzing the results of growing crops nationwide from 1999 to 2016 and the change in the annual yields of developed varieties and recently developed varieties as basic data to investigate the growth status of the crops in the country. As a result of annual comparisons of the yields of Taebongbyeo (2000) and Ungwangbyeo (2004) developed in the early 2000s for Odaebyeo, which was developed in the 1980s, the annual yields were relatively higher in varieties in the 2000s despite the increase in temperature. The annual yields of Samgwangbyeo (2003) and Saenuribyeo (2007), which were recently developed as mid-late-type varieties, were higher than those of an earlier developed variety called Chucheongbyeo, which was developed in the 1970s. Despite the rapid increase in temperature, rice cultivation technology and variety development are well adapted to climate change. However, since the biological potential of rice could reach its limit, it is necessary to develop continuous response technology.