• Ecology and Resilient Infrastructure
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• v.2 no.2
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• pp.137-146
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• 2015

Lateral connectivity between a main channel and a former channel plays an integral role in maintaining ecological functions of stream-floodplain ecosystems. This study virtually restored the connectivity of the former channel, which is currently isolated by channelization, in the Mangyeong River, Korea. Fish habitat improvement after the connectivity restoration was evaluated using River2D, two-dimensional depth-averaged hydraulic modeling, depending on normal and flood flow conditions. Target fish species were crucian carp (Carassius auratus), which are known as lentic species, and pale chub (Zacco platypus), known as lotic species. The weighted usable area (WUA) of the two species was increased after the connectivity restoration: the two-way connection between the main and formal channels was more effective than the one-way connection. The result of the physical habitat simulation at a flood flow condition demonstrated an increased rate of the WUA than during a normal flow condition. In particular, the WUA of pale chub increased about four times on the two-way connectivity restoration. This result suggests that habitat availability of both lentic and lotic fish species will increase after a connectivity restoration, and a two-way connectivity restoration may be more effective. In addition, the restored formal channel would function as a shelter for fish during the flood season.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.308-321
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• 2013

In order to understand the population dynamics of red tide dinoflagellate Noctiluca scintillans, we examined its hydrographical and bio-ecological characteristics at 19 to 20 stations of Gwangyang Bay during all four seasons from 2010 to 2012. During the 3-year period, N. scintillans was seasonally abundant during summer with water temperatures ranging from $15^{\circ}C$ to $22^{\circ}C$ and salinity ranging from 25 psu to 30 psu. On the other hand, N. scintillans population density significantly decreased in spring, fall and winter, although they were present even in lower temperatures (< $4^{\circ}C$). However, high water temperature (> $27^{\circ}C$) and low salinity (< 12 psu) led to the disappearance of N. scintillans population. Chl-a concentration in winter, spring and fall was positively correlated with N. scintillans population density, whereas the N. scintillans population was negatively correlated with Chl-a concentration in summer. This implies that densities of prey population such as diatoms are one of important contributing factor for maintaining abundance of N. scintillans in winter, spring and fall and for increasing abundance of N. scintillans in summer. During summer season, bio-accumulation of N. scintillans population by the wind from southwest is also considered to be a key factor in triggering the formation of large-scale blooms in Gwangyang Bay.

• Analytical Science and Technology
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• v.13 no.4
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• pp.453-465
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• 2000

Polycyclic aromatic hydrocarbons (PAHs) were produced by thermoreaction (incompletely combustion) of organic compounds such as fuel, gasoline, diesel etc, and were known the strong carcinogenic compounds. In our country, a study for health risk assessment of PAHs in air were needed according to rapidly increasing of motor vehicle and progressing to industrial country. In this study, concentrations of PAHs in 263 air samples of fourteen sites-Seoul, Pusan, etc-according to four times sampling for one year are measured by GC/MSD for basic research for health risk assessment. As the result, 14 PAHs are detected in all samples and annual average concentration of total PAHs was $28.72ng/m^3$ and highest average concentration of total PARs was $47.76ng/m^3$ in winter season. The concentrations of total PAHs are proportioned to amount of extracted organic material (EOM). The average concentration of total PAHs in EOM was 0.28%.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.3
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• pp.100-110
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• 2009

'Hongro' is one of the important mid-season apple cultivars bred in Korea. The recent occurrence of water core in Hongro and the consequent problems motivated this study. The objectives of our study were to investigate the influence of air temperature during the growing period on water core occurrence in Hongro and to provide methods to mitigate its impact. Based on our field experiments for three years, the results indicated that the occurrence of water core disorder was due to the prolonged exposure to high temperature ($T_a$) of >$30^{\circ}C$ during the ripening period. The rates of occurrence of water core disorder were higher in the fruit whose weight was more than 300g or those located outside the tree canopy and thus exposed to stronger solar radiation. In terms of mitigating the water core occurrence, the application of spraying $CaCl_2$ four times from late July to August was effective. Furthermore, between 1 and 15 August when the rate of occurrence was high with $T_a$ (from 3:00 to 5:00 p.m.) >$30^{\circ}C$, the micro-water sprinkling for 30 minutes starting at 6:00 p.m. with a supplementary spray conducted two hours after the first application drastically reduced the water core occurrence.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.1 s.114
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• pp.92-106
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• 2006

The process of designing Cheonggyecheon Entrance Plaza began with researching four keywords: plaza, restoration. modernity and icon. The outcome of the research was reinterpreted into and informed the design. An urban plaza must not only be a stage for civic life but should also be a portrait of the city to which it belongs. Many Korean plazas, however, are treated as if they are parks. Yeouido Park, which was originally a vast urban void, and Seoul Plaza, recently paved with grass, are good example. The strong 'green myth' can hinder socio-political activities. Cheonggyecheon cannot be said to have been 'restored', since it is still disconnected from its origin and upper streams, and the water is circulated by electricity. So it is better understood as an artificial urban waterfront, rather than an ecologically restored stream. This fact might diminish its ecological value, but not its recreational one. The entrance plaza therefore should reflect that the new stream brings back an 'experience', not only water itself. At the same time, the catch phrase of this restoration project was 'post-modern'. The demolished Cheonggye Expressway represents the 'economy drive' of the 1970s, so the newly opened Cheonggyecheon serves as a perfect counterpart to it. But modernity in Korea is the spirit that made many of the good things, not only its shortcomings, we have now. And from the philosophy of this restoration project, we can see that it is still an ongoing attitude in a way. Remnant of Cheonggye Expressway can evoke our nostalgia for the era. There are plenty of symbols in Seoul, both as architecture and objects. But none of them provide citizens with experience, other than the experience of looking at them. Cheonggyecheon Entrance Plaza is a good place to serve as an icon for a dynamic Seoul. From the research, the designer concluded that this plaza should commemorate the incomparable horizontal experience of Cheonggyecheon and the old expressway, amid the vertical metropolis. The Pedestrian Sculpture, which people can stroll on and look out over Cheonggyecheon, is to be made of steel cladding with a core structure and represents the dynamism of the stream, Seoul and contemporary Korea. The choice of material and the steel structure are also ways of creating the icon. The Water Plaza, the space underneath the ramp, will accommodate people and their urban activities, providing an opportunity to play with water. The Waterblades will be a device for the dramatic beginning of the stream, simultaneously camouflaging ugly openings in the outlets. The Wall of Archaeology is to be made with pre-fab resin blocks, translucent enough so that people can see through any archaeological findings of the site. The strong water-resistant character of resin makes the wall steady throughout the flood season as well. Cheonggyecheon restoration project is an effort to combine contemporary urban demand with the once-existing physicality by evoking our nostalgia for it. The project itself shows many socio-political issues of present-day Korea. The entrance plaza design thus is focused on suggesting an icon for the metropolis, simultaneously celebrating the stream itself. Within this space, people will be exposed to a unique experience that any 'green myth' cannot offer.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.784-788
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• 2015

A new cultivar 'Picnic' originated from an artificial cross between 'Fuji' and 'Sansa' at National Institute of Horticultural & Herbal Science in 1994. The cultivar was preliminarily selected among the elite siblings for its high fruit quality in 2003. After regional adaptability tests in five districts for four subsequent years as 'Wonkyo Ga-34', it was ultimately selected in 2008. Optimum harvest time is late September. Mature fruit has mean weight of 233 g and is conic with light red skin on a greenish yellow ground and yellowish white flesh. The fruit contains a favorable total soluble solids content at $13.8^{\circ}Brix$ and titratable acidity at 0.43%, which results in gustatory harmony between sugars and acids. It is not resistant to bitter rot or Marssonina blotch. 'Picnic' exhibits a physiological cross compatibility with leading cultivars such as 'Fuji', 'Hongro' and 'Tsugaru'. Tree topology is semi-spreading with a weak growth habit.

• Journal of Fashion Business
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• v.12 no.5
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• pp.1-13
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• 2008

This study is largely aimed at presenting ways to improve the working clothes and help companies create more positive images by suggesting designs of the clothes, which take into accounts the corporate image, symbolism, function and aesthetic appreciation through introduction of companies' CIP. And, it is significant to propose working clothes development condition and process with introduction of companies' CIP(Corporate Identity Program : work that systematize and simplify visually images which companies or public bodies have) A way of this study was made up with working clothes design development process which a student planned. First of all, this study looked into Company D's Corporate Identity Program(CIP) to develop the design that corresponds with the characteristics of the company's favorite design, working environment and demands of the employees. And, then, the study conducted a survey of 30 employees and intensive interviews with heads of four teams including the Safety Team, the Working Clothes Management Team and the General Affairs Team to find out the requirements of the clothes and the characteristics of the company. Based on them, the concrete image that the company pursues and the direction of design were set up through image positioning. In the end, three different concept designs were presented through image-mapping and the concrete design of each item was developed. A total of seven items including upper and lower garments (a jacket and trousers) for the spring-summer seasons, upper and lower garments (a jumper and trousers) for the winter season, cold-protecting vest and winter clothes (a coat and trousers) were presented in accordance with the three concepts. One of the concept designs, which was selected through evaluation by employees of Company D, was produced as a sample and then the final design was chosen after a discussion attended by the head of each team and representatives of the employees. Based on the aforementioned design planning, one design was selected from each of the three concept designs for production. And each of these was requested to special production enterprise and manufactured. Following the result of study, by looking into a case of a practical joint design project between a university and a company, this study suggested ideas for business to improve working clothes through the academic-industrial cooperation and presented conditions and process of design development. And, this study also aims to examine the feasibility of academic-industrial cooperation based on the cases in which enterprises and universities staged joint projects to develop working clothes.

• Journal of Korea Water Resources Association
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• v.52 no.10
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• pp.729-742
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• 2019

Natural disasters such as floods has been increased in many parts of the world, also Korea is no exception. The biggest part of natural damage in South Korea was caused by the flooding during the rainy season in every summer. The existing flood vulnerability analysis cannot explain the reality because of the repeated changes in topography. Therefore, it is necessary to calculate a new flood vulnerability index in accordance with the changed terrain and socio-economic environment. The priority of the investment for the flood prevention and mitigation has to be determined using the new flood vulnerability index. Total 25 urban districts in Seoul were selected as the study area. Flood vulnerability factors were developed using Pressure-State-Response (PSR) structures. The Pressure Index (PI) includes nine factors such as population density and number of vehicles, and so on. Four factors such as damage of public facilities, etc. for the Status Index (SI) were selected. Finally, seven factors for Response Index (RI) were selected such as the number of evacuation facilities and financial independence, etc. The weights of factors were calculated using AHP method and Fuzzy AHP to implement the uncertainties in the decision making process. As a result, PI and RI were changed, but the ranks in PI and RI were not be changed significantly. However, SI were changed significanlty in terms of the weight method. Flood vulnerability index using Fuzzy AHP shows less vulnerability index in Southern part of Han river. This would be the reason that cost of flood mitigation, number of government workers and Financial self-reliance are high.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.6
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• pp.488-494
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• 2007

Highland regions for farming are generally located in slopes higher than 7%, where alpine farming systems rely on highly input agriculture management with great amounts of chemical fertilizer and/or compost. Most of the uplands is thus needed to maintain environmentally friendly soil management due to its impact on soil erosion and runoff during heavy rainfall season. Therefore, the objective of this research is to evaluate the effect of reduction of soil erosion by applying four wild edible greens (fatsia, goat beard, leopard plant, and aster). The lysimeter experiment of slope gradients of 15, 30, and 45% was conducted in an alpine region of Hoengkye, Kangwon, in 2005 and 2006. In 2005, both amounts of soil loss from the experiment plots cultivated with goat beard and aster were lower than one with Chinese cabbage by about 50%. The amounts of runoff of goat beard and aster plots were also lower than those of the others. An increase in the slope gradients was accompanied with an increase in runoff. Of the plots of slope gradient of 15, 30, and 45%, S of goat beard plots was 52.50, 108.33, and 171.50 kg, respectively. Soil loss of Chinese cabbage was 2 to 3 times as high as those of goat beard plots. These results suggest that goat beard and aster plants with minimum tillage reduce soil erosion compared to Chinese cabbage cultivation.

• Food Engineering Progress
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• v.13 no.4
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• pp.308-313
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• 2009

This study was conducted to design and fabricate a heat pump that can produce some weather conditions similar to those of the dry season of the rough rice in Korea, and to investigate basic performances of the apparatus. During the drying test, the amount of energy consumption and drying characteristics were measured at four different temperature levels ranging between 20$^{\circ}C$ and 50${^{\circ}C}$. In the psychrometric chart, the freezing capacity and refrigerant circulation ratio of the heat pump were 173 kJ/kg and 49.6 kg/hr, respectively. Therefore, coefficient of performance was 5.5, which was superior to that of refrigerant R-22 (4.0) in standard refrigeration cycle. In addition, the time to reach target drying temperature (30${^{\circ}C}$) and relative humidity (40%) were 6 minutes and 7 minutes, respectively. Temperature differences between the drying temperature and the rice were 1.5${^{\circ}C}$ and 8.5${^{\circ}C}$ at the drying temperatures of 21.9${^{\circ}C}$ and 48.7${^{\circ}C}$, respectively. This result demonstrated that the increased temperature of the rice in the drying section decreased sufficiently in the tempering section. At the drying temperatures of 21.9, 30.7 38.8, and 48.7${^{\circ}C}$, drying rates were 0.29, 0.61, 0.85, and 1.26%/hr, respectively, which were similar to those of commercial dryer. In addition, the amounts of energy consumption were 325, 667, 692, and 776 kJ/kg, respectively. These results showed that this dryer saved up to 86% of energy consumption compared with the commercial dryer, which uses 4,000-5,000 kJ/kg of fossil fuel.