• Journal of Korean Society on Water Environment
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• v.22 no.6
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• pp.1101-1106
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• 2006

Many BNR (Biological Nutrient Removal) plants have experienced a bulking problem, mainly due to the growth of filamentous organisms, particularly during the winter months. This study investigated the problem of bulking due to the growth of M. parvicella both at a full-scale municipal wastewater treatment plant and a pilot scale plant located in the C city. The full-scale facility was operated at a flow rate of $51,000m^3/d$, an F/M (Food-to-Microorganism) ratio of 0.12 kgBOD/kgMLVSS/d and an SRT (Solids Retention Time) higher than 25 days, respectively. This plant experienced bulking and foaming problems at low temperatures below $15^{\circ}C$ since it was retrofitted with the BNR system in 2003. The pilot plant employed had an identical process configuration as the full scale one and used the same wastewater source. It was operated at a flow rate of $3.8m^3/d$, temperatures between 10 to $25^{\circ}C$ and SRTs between 10 and 25 days. At full scale, the M. parvicella growth and SVI (Sludge Volume Index) patterns were studied in conjunction with temperature variations. At pilot scale, DO and SRT variations were also explored, in addition to the filamentous bacteria growth and SVI patterns. During the full-scale investigation, over a 3 year period, it was noted that the SVI was maintained within acceptable operational values (i.e. under 160) during the summer months. Moreover settling in the secondary clarifiers was good and was not affected by the presence of M. parvicella. In contrast, at low mean temperatures during winter, the SVI increased to over 300. Overall, as the temperature decreased, the predominance of M. parvicella became apparent. According to this study, M. parvicella growth could be controlled and SVI could drop under 160 by a change in operational conditions which involved an increase in DO concentration between 2 and 4 mg/L and a decrease in SRT to less than 20 days.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1997.11a
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• pp.3-31
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• 1997

Water has always played a significant role in the lives of people. In urbanised Rome, with its million people. sophisticated supply systems developed and then fled with the empire. only to be rediscovered later But it was the industrial Revolution commencing in the eighteenth century that ushered in major paradigm shifts In use and altitudes towards water. Rapid and concentrated urbanisation brought problems of expanded demands for drinking supplies, waste management and disease. The strategy of using water from local streams, springs and village wells collapsed under the onslaughts of rising urban demands and pollution due to poor waste disposal practices. Expanding travel (railways. and steamships) aided the spread of disease. In England. public health crises peaks, related to water-borne typhoid and the three major cholera outbreaks occurred in the late eighteenth and early nineteenth century respectively. Technological, engineering and institutional responses were successful in solving the public health problem. it is generally accepted that the putting of water into pipe networks both for a clean drinking supply, as well as using it as a transport medium for removal of human and other wastes, played a significant role in towering death rates due to waterborne diseases such as cholera and typhoid towards the end of the nineteenth century. Today, similar principles apply. A recent World Bank report Indicates that there can be upto 76％ reduction in illness when major water and sanitation improvements occur in developing countries. Water management, technology and thinking in Australia were relatively stable in the twentieth century up to the mid to late 1970s. Groundwater sources were investigated and developed for towns and agriculture. Dams were built, and pipe networks extended both for supply and waste water management. The management paradigms in Australia were essentially extensions of European strategies with the minor adaptions due to climate and hydrogeology. During the 1970s and 1980s in Australia, it was realised increasingly that a knowledge of groundwater and hydrogeological processes were critical to pollution prevention, the development of sound waste management and the problems of salinity. Many millions of dollars have been both saved and generated as a consequence. This is especially in relation to domestic waste management and the disposal of aluminium refinery waste in New South Wales. Major institutional changes in public sector water management are occurring in Australia. Upheveals and change have now reached ail states in Australia with various approaches being followed. Market thinking, corporatisation, privatisation, internationalisation, downsizing and environmental pressures are all playing their role in this paradigm shift. One casualty of this turmoil is the progressive erosion of the public sector skillbase and this may become a serious issue should a public health crisis occur such as a water borne disease. Such crises have arisen over recent times. A complete rethink of the urban water cycle is going on right now in Australia both at the State and Federal level. We are on the threshold of significant change in how we use and manage water, both as a supply and a waste transporter in Urban environments especially. Substantial replacement of the pipe system will be needed in 25 to 30 years time and this will cost billions of dollars. The competition for water between imgation needs and environmental requirements in Australia and overseas will continue to be an issue in rural areas. This will be especially heightened by the rising demand for irrigation produced food as the world's population grows. Rapid urbanisation and industrialisation in the emerging S.E Asian countries are currently producing considerable demands for water management skills and Infrastructure development. This trend e expected to grow. There are also severe water shortages in the Middle East to such an extent that wars may be fought over water issues. Environmental public health crises and shortages will help drive the trends.

• Journal of Bio-Environment Control
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• v.22 no.2
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• pp.138-145
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• 2013

In order to develop the efficient control algorithm of the two-fluid fogging system, cooling experiments for the many different types of fogging cycles were conducted in tomato greenhouses. It showed that the cooling effect was 1.2 to $4.0^{\circ}C$ and the cooling efficiency was 8.2 to 32.9% on average. The cooling efficiency with fogging interval was highest in the case of the fogging cycle of 90 seconds. The cooling efficiency showed a tendency to increase as the fogging time increased and the stopping time decreased. As the spray rate of fog in the two-fluid fogging system increased, there was a tendency for the cooling efficiency to improve. However, as the inside air approaches its saturation level, even though the spray rate of fog increases, it does not lead to further evaporation. Thus, it can be inferred that increasing the spray rate of fog before the inside air reaches the saturation level could make higher the cooling efficiency. As cooling efficiency increases, the saturation deficit of inside air decreased and the difference between absolute humidity of inside and outside air increased. The more fog evaporated, the difference between absolute humidity of inside and outside air tended to increase and as the result, the discharge of vapor due to ventilation occurs more easily, which again lead to an increase in the evaporation rate and ultimately increase in the cooling efficiency. Regression analysis result on the saturation deficit of inside air showed that the fogging time needed to change of saturation deficit of $10g{\cdot}kg^{-1}$ was 120 seconds and stopping time was 60 seconds. But in order to decrease the amplitude of temperature and to increase the cooling efficiency, the fluctuation range of saturation deficit was set to $5g{\cdot}kg^{-1}$ and we decided that the fogging-stopping time of 60-30 seconds was more appropriate. Control types of two-fluid fogging systems were classified as computer control or simple control, and their control algorithms were derived. We recommend that if the two-fluid fogging system is controlled by manipulating only the set point of temperature, humidity, and on-off time, it would be best to set up the on-off time at 60-30 seconds in time control, the lower limit of air temperature at 30 to $32^{\circ}C$ and the upper limit of relative humidity at 85 to 90%.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.6
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• pp.81-90
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• 2009

This study seeks those elements that form a sense of place in Yen-Ben Street, which represents a typical ethnic enclave in Seoul, to provide a basic resource in the creation of an urban landscape that can provide a positive space for cultural diversity. The results of the study can be summarized as follows: First, the element of a physical environment that develops a sense of place was in fact the poor dwellings that correspond to the economic condition of Korean Chinese. While this element has a negative cognition to outsiders, Korean Chinese feel positively toward it. Secondly, signboards were a physical element of sense of place which retains cultural identity as a means of communication inside the community. Thirdly, it was found that activities such as shopping, recreation, and the exchange of information that are found in the pursuit of daily life act as an essential element in the formation of a sense of place even more than architectural elements. Fourthly, the appropriation of space by Korean Chinese and the isolation from the surroundings were obvious. This isolation is perceived as a negative sense of place formation to outsiders in Yen-Ben Street. Fifthly, the aspects of cultural dualism, mingling the concepts of home country, language, writing, and food have also affected the formation of a sense of place in the area. Sixthly, transience was a prominent phenomenon of Yen-Ben Street and is strengthened by illegal immigration. Although transience causes negative impacts such as in a lack of concern for the residential environment, it acts as a positive factor in the sense of place by mitigating uneasiness, and strengthening insider ties and cooperation.

• Journal of Bio-Environment Control
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• v.21 no.2
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• pp.88-94
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• 2012

This study was carried out in order to investigate the effect of temperature of treatment and storage on the longevity of 'Unicorn' tomatoes of light red maturity stage during commercial handling conditions encountered while exporting over long distances. Tomato stored at $5^{\circ}C$ and $11^{\circ}C$ temperature with 85% relative humidity by pre-treating handling temperature that was using from field to before shipment as a winter temperature $5^{\circ}C$, spring temperature $11^{\circ}C$ and summer temperature $25^{\circ}C$ for 3 days. On the final storage day, $25^{\circ}C/11^{\circ}C$ (treated/stored) tomatoes showed the highest respiration and ethylene production rate; whereas the lowest respiration and ethylene production rate was found for $5^{\circ}C/5^{\circ}C$ treated and stored tomatoes. Tomatoes treated and stored at $5^{\circ}C/5^{\circ}C$ showed higher marketability, without evidence of fungal rot, decay or spots for 23 days. The fresh weight loss under all treatment conditions increased gradually during $5^{\circ}C$ and $11^{\circ}C$ storage temperatures. The higher firmness and soluble solids were determined from $5^{\circ}C/5^{\circ}C$ and $5^{\circ}C/11^{\circ}C$ treated and stored tomatoes repectively, than from others tomatoes on the final day of storage. In addition, $5^{\circ}C/5^{\circ}C$ tomatoes showed higher vitamin C contents than tomatoes stored at other temperatures, on the final day of storage. As the ripening and storage period progressed, the titratable acidity increased, but declined (P < 0.05) thereafter, due to over ripe tomatoes under all treatment conditions. These results show that $5^{\circ}C/5^{\circ}C$ treated and stored light red maturity stages of 'Unicorn' tomatoes are optimum to export because they show the highest storability and marketability. Moreover, the marketability of light red maturity stage of 'Unicorn' tomato maintained for 2 weeks in $25^{\circ}C/11^{\circ}C$ treated and stored temperature that might be the export temperature from Korea to Japan in summer season. This research result could be useful in helping tomato growers and exporters to get optimum market value by satisfying the buyer and consumer with a fresher product.

• Journal of Wetlands Research
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• v.19 no.2
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• pp.230-239
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• 2017

These days, the demand of farm tours is on the rise in Korea. However, most of them are related to farming experience. To overcome the situation, ecological experience is introduced. In this sense, it is necessary to obtain the contents and educational materials of ponds, the space of farming and ecological experience. Therefore, this study analyzed the use patterns of oriental medicine of pond wetland plants. Oriental medicine is used for old and traditional knowledge, and is still applied to various fields, such as medical science, pharmacy, and science. The analyzed result of this study will be helpful for the educational materials of ecological experience. This study surveyed plants of 40 pond wetlands in rural areas, and looked into the use patterns of traditional medicine by using the contents of Korea Traditional Knowledge Portal being operated by Korean Intellectual Property Office. According to the vegetation survey of the 40 pond wetlands, there were a total of 457 taxa in 108 families, 309 genera, 392 species, 59 varieties, 5 forma, and 1 subspecies. Among them, 314 taxa in 53 families, 136 genera, 265 species, 45 varieties, 3 forma, and 1 subspecies had the information on the use patterns of traditional medicine. It means that 68.8% of the plants around pond wetlands contain traditional medicine. Given other application patterns, such as food, handcraft and traditional farming, more than 70~80% are expected to include traditional knowledge. 314 taxa used for traditional medicine had 570 kinds of efficacy and 325 kinds of disease treatment. It means that one taxon has 4.0 (0~20) kinds of efficacy on average and 6.6(0~20) kinds of disease treatment. It is expected that this study result will be applied to various fields, including experience, education, and medical science. And it is considered that valuable pond wetlands are worthwhile to be conserved constantly.

• Membrane Journal
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• v.24 no.3
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• pp.213-222
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• 2014

In this study, 2-stage recirculation membrane process was developed for purification of high purity bio-methane for the vehicle fuel application. Pure gas permeation and mixture gas permeation test were done as a function of methane content and pressure in the feed using polysulfone membrane modules. 2-stage membrane plant was designed, constructed in a food waste treatment cite. Dehumidification, dry desulfurization, and desiloxane plants are installed for the removal of $H_2O$, $H_2S$ and siloxane in the biogas. Permeation test were done with the pre-treated methane mixture in terms of methane purity and recovery by adjusting the ratio of membrane area (1:1, 1:3, 2:2) in the first and second membrane modules in the plant. When membrane area of 2 stage increased to $3m^2$ from $1m^2$ at 1-stage membrane area of $1m^2$, the feed rate and $CH_4$ recovery at 95% methane purity were increased from 47.1% to 92.5% respectively. When the membrane area increased two-fold (1:1 to 2:2), $CH_4$ recovery increased from 47.1% to 88.3%. When the feed flow rate was increased, in 1:3 ratio, final purity of the methane is reduced, the methane recovery is increased. When operating pressure was increased, the feed rate was increased and recovery was slightly decreased. From this result, membrane area, feed pressure and feed rate could be the important factor to the performance of the membrane process.

• Journal of Korean Society of Forest Science
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• v.37 no.1
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• pp.1-16
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• 1978

The study describes on the identification and morphological characteristics of each species, ecological characteristics and propagation techniques, and developing utilization measures of the Parthenocissus plants for environment conservation and revegetation of the babe rock-slopes. The following species and varieties are disscussed in this study; Parthenocissus tricuspidata (S. et Z.) Planch. var. veitchii Rehd. var. lowii Rehd. var. pupurea Hort. Parthenocissus quiquefolia (L.) Planch. var. engelmanni Rehd. var. saint-pauli Rehd. var. hirsuta Planch. Parthenocissus henryana Diels et Gilg. Parthenocissus thomsoni Planch. Parthenocissus heptaphylla Small. Parthenocissus inserta (Kern.) K. Fritsch. Parthenocissus laetevirens Rehd. Parthenocissus himalayana Planch. These are, in general, all vigorous self-clinging climbers that will quickly cover a wall and bare rock surfaces with a dense network of branch growths and beautiful green leaves which change to shades of scarlet and crimson before they fall in Autumn. Parthenocissus tricuspidata out of 8 species in the genus Parthenocissus is the most useful plant for the environment conservation including the bare rock-slope revegetation and for the production of food and shelter for wildlifes. This native of Korea clings by means of small rootlike holdfasts (adhesive discs) and holds (tendrils) to stone work or any other solid support, tenaciously.

• Journal of Korea Soil Environment Society
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• v.3 no.2
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• pp.13-29
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• 1998

Recently, It is increasing popularity to research on the soil remediation in aspect of management by reason of the hazardous impact on the contaminated soil in Korea. It was investigated high levels of arsenic salts in soil near abandoned five mines(Darak, Daduk, Jingok, Dalsung, Ilkwang) located in Youngnam area. Arsenic, classified as group A(Human Carcinogens) from IRIS, have shown statistically significant increment in skin cancer with oral exposure. This paper was conducted to predict excess cancer risk value (to the skin cancer) based on multiple pathway such as soil ingestion, dermal uptake and food(plant) ingestion contaminated by arsenic, and also, to identify the remedial goal regarded in future land use. The mine having the highest arsenic level was Daduk(mean : 1950mg/kg) and the next rank was Jingok(1690mg/kg), Ilkwang(352.37mg/kg), Dalsung(86.08mg/kg), Darak(0.83mg/kg). The chronic daily intake to the multiple exposure were calculated using Monte-Carlo simulation regarded in future land use and used q: value was $1.5(mg/kg/day)^{-1}$ to the oral proposed by IRIS(1997). The computated excess cancer risk 95th value to all the mine regarding future land use as residential and rural area were more than $10^{-4}$. If the level of acceptable risk is aimed for 1$\times$$10^{-6}$, it could be used Darak as commercial and industrial area without soil remediation due to the lowest risk value(6$\times$$10^{-8}$ and 3$\times$$10^{-8}$). Computated remedial goal based on 1$\times$$10^{-6}$ of acceptable risk to the future land use as the residential, rural, commercial and industrial area were 0.02mg/kg, 0.003mg/kg, 97.31mg/kg and 194.62mg/kg, respectively.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.1
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• pp.92-102
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• 2020

The followings are the landscape preference aspects from the 816 landscapes(景, Kyung), which comprise the 78 modern Palkyungs, presented by the 78 local governments in Korea. First, the natural environment elements selected as Kyung(景), which are topographical landscapes, mostly consist of mountain elements such as mountains, terrace(臺), rocks and stones and water elements classified as rivers, oceans, and lakes. Natural elements also include old-growth and giant trees such as pines, ginkgos, Japanese cornels and fringe trees, tree-lined streets and forests, and plant elements such as azaleas, rhododendrons, lotuses, reeds, and silver grasses which provide seasonal landscapes. Second, more than half of Kyung, selected as human environment elements, are historical and cultural heritages such as graveyards, mountain fortresses, town fortresses, traditional villages, pavilion in villas, and temples. And it is followed by leisure tourism facilities such as traditional markets, exhibition halls, theme parks, beaches, and food streets, green-based structures such as trails, plazas, parks, and botanical gardens, and industrial heritages such as ranches, abandoned coal mines, stations, ports and bridges. Third, modern Palkyungs include objects not related to the views such as local representative facilities, regional products, and festivals. Fourth, although most of the modern Palkyungs consist of eight, some include 20, 38, or 100 in order to increase the number of objects of public relations. Fifth, a certain local government makes two modern Palkyungs with different subjects by introducing traditional Palkyung and modern Palkyung altogether. In this case, it presents several modern Palkyungs like by selecting Palkyungs in a limited area. Furthermore, one Palkyung includes numerous place names at a time in some cases. Sixth, Sosangjeonhyeong(瀟湘典型)-style modern Palkyung uses 'NakAn(落雁)' as the name of Kyung. Sosangyusahyeong(瀟湘類似型)-style modern Palkyung expresses 'Hyojong(曉鐘)' and landscape of glow of the setting sun, sunset, night view, dawn, sunrise and depicts cloud, sunset, moon, and snow. There are many Myeongsocheheomhyeong(名所體驗型)-style Palkyungs exhibiting the behavior of tourism and Myeongseunghyeong(名勝型)-style Palkyungs raising the awareness only by the names of the places. Seventh, modern Palkyung's naming styles are diverse, such as using only four letters instead of specifying Kyungmul(景物) or Kyungsaek(景色) in combination with Chinese characters or adding modifiers specializing in places.