• Horticultural Science & Technology
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• v.34 no.1
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• pp.195-205
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• 2016

Sugar beet cyst nematode, Heterodera schachtii, causes serious economic losses worldwide in Brassicaceae crops. In 2011, this nematode was first found in highland vegetable cultivation areas in Korea, and thereafter spread to the surrounding healthy Chinese cabbage fields. However, little has been documented on the biological and ecological characteristics of the sugar beet nematode in highland vegetable cultivation areas. In this study the dispersal of the sugar beet cyst nematode was examined, focusing on spreading through soil and/or water infested with the nematode. When farmers with work boots trampled on Chinese cabbage fields for 10 minutes, the number of cysts recovered from the soil attached to the working differed depending on the research sites. Under irrigation conditions of 2, 4, and 8 liters of water per $m^2$, the amounts of soils attached on the bottom of the work boots and the number of healthy cysts in the soils increased significantly with the increase in soil moisture, although the total number of cysts, eggs, and juveniles did not increase significantly. After driving on the farm road adjacent to cabbage fields infested with the sugar beet cyst nematode, cysts were also recovered from the soil attached to the vehicle's tires, suggesting that the sugar beet cyst nematode can spread to new fields through soil carried by vehicles and by farmers. An excavator and a motor truck could deliver 41 kg and 224 g, respectively, of soil on the shovel shoes and the wheels to other locations during the Chinese cabbage harvest, suggesting that farming equipment and transportation vehicles may be vital means by which the cyst nematode spreads to non-infested fields in the highland area of Korea. Runoff water also contained cysts, whose amounts increased after water irrigation onto the ridges to simulate rainy conditions, with no significant difference in the number of cysts with increasing amounts of irrigation water. All of these results confirmed that the sugar beet cyst nematode spreads through soil attached to work boots, harvesting tools, and transportation vehicles, especially during the harvest time, and through runoff water on rainy days. These observations suggest that personal sanitization and cleaning of working tools and vehicles are one of the most important means to prevent the dispersal of the sugar beet cyst nematode in fields.

• Tuberculosis and Respiratory Diseases
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• v.58 no.2
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• pp.167-173
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• 2005

Background : Airborne particles during Yellow Sand phenomena are known to be associated with the respiratory disease. The purpose of this study was to evaluate the concentration and metal component properties of Yellow Sand particles and compare with airborne microbial concentration and species in non Yellow Sand and Yellow Sand phenomena. Methods : Samplings were carried out in 2002 in Seosan, during non Yellow Sand and Yellow Sand phenomena. Samples were taken using the 8-stage Cascade impactor and metallic elements were analyzed by XRF. Those were culture on the media for bacterial and fungal culture and celline for virus. Results : The concentration of total suspended particulate matter were respectively $80.2{\mu}g/m^3$, $40.3{\mu}g/m^3$ in non Yellow Sand and Yellow Sand phenomena. The concentration of metallic elements such as Ca, Fe, Cu and Zn in Yellow Sand phenomena were higher than its in non Yellow Sand. Two bacteria, Bacillus species and Staphylococcus were grown in two periods. In both periods, several fungal spores(Mucor species, Cladosporum, Alternaria, Aspergillus, Penicillium, and Alternaria species) were identified. The differences of bacteria and fungus species not observed in Yellow Sand and non Yellow Sand. Any viruses were not isolated in between both periods. Conclusions : The concentration of total suspended particulate matter and some metallic elements in Yellow Sand phenomena were higher than its in non Yellow Sand. The difference of bacteria and fungus species was not observed in non Yellow Sand and Yellow Sand phenomena.

• Archives of design research
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• v.20 no.3 s.71
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• pp.151-162
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• 2007

How can new media devices and networks provide an effective response to the world's growing sector of cultural and historically-minded travelers? This study emerged from the question of how mobile handsets can change the nature of cultural and historical tourism in ubiquitous city environments. As wireless network and mobile IT have rapidly developed, it becomes possible to deliver cultural and historical information on the site through mobile handset as a tour guidance system. The paper describes the development of a new type of mobile tourism platform for site-specific cultural and historical information. The central objective of the project was to organize this cultural and historical walking tour around the mobile handset and its unique advantages (i.e. portability, multi-media capacity, access to wireless internet, and location-awareness potential) and then integrate the tour with a historical story and role-playing game that would deepen the mobile user's interest in the sites being visited, and enhance his or her overall experience of the area. The project was based on twelve locations that were culturally and historically significant to Korean War era in Busan. After the mobile tour game prototype was developed for this route, it was evaluated at the 10th PIFF (Pusan International Film Festival). After use test, some new strategies for developing mobile "edutainment content" to deliver cultural historical contents of the location were discussed. Combining 'edutainment' with a cultural and historical mobile walking tour brings a new dimension to existing approaches of the tourism and mobile content industry.

• Korean Journal of Environmental Agriculture
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• v.16 no.1
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• pp.19-24
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• 1997

This studies was carried out to investigate the soil contamination and water quality affected by agricultural activities in the Keum river Districts. Soil pH of the Keum river districts were $5.56{\sim}7.09$ in Keum river headwater and Namdae-cheon but that of Keumgang-lake were $5.07{\sim}7.21$ because of the cattle shed and industrial complex around. Total nitrogen contents of soils were found difference as period of fertilizer application. Total phosphorous content of soils no difference were found between the headwater and Keumgang-lake. Heavy metal contents of soils were natural background level. Water pH of the Keum river districts ranged from 6.59 to 7.80 and COD was maintain below 1.0 mg/L. Total nitrogen content affected by a livestock wastes and sewage water were the higher than that of others and total phosphorous content showed below 0.5 mg/L. Nitrate nitrogen and ortho-phosphate contents were very high according to the influence a livestock waste and sewage water in headwater region of the Keum river partly. Chlorine and sulfate contents were high according to the influence of sea water invasion. Heavy metal contents of waters were natural background level.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.56-63
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• 2018

The management of Combined Sewer Overflows(CSOs) and Separated Sewer Overflows(SSOs) discharge directly to the effluent system in an untreated state, which occurs when the facility capacity is exceeded due to heavy rain, has become an important issue in recent years as the heavy rain becomes a regular phenomenon. Despite the continuous development of filtration technology, targeting densely populated urban areas, CSOs are rarely applied. Therefore, this study was carried out to optimize the process to apply CSOs in a pilot-scale horizontal flow filtration system with a rope-type synthetic fiber. The research was carried out in two steps: a preliminary study using artificial samples and a field study using sewage. In the preliminary study using an artificial sample, head loss of the filter media itself was analyzed to be approximately 1.1cm, and the head loss was increased by approximately 0.1cm as the linear velocity was increased by 10m/hr. In addition, the SS removal efficiency was stable at 81.4%, the filtration duration was maintained for more than 6 hours, and the average recovery rate of 98% was obtained by air backwashing only. In the on-site evaluation using sewage, the filtration duration was approximately 2 hours and the average removal efficiency of 83.9% was obtained when belt screen (over 450 mesh) was applied as a pre-treatment process to prevent the premature clogging of filter media. To apply the filtration process to CSOs and SSOs, it was concluded that the combination with the pre-treatment process was important to reinforce the hydraulic dimension for the stable maintain of operation period, rather than efficiency. Compared to the dry season, the quality of incoming sewage was lower in the rainy season, which was attributed to the characteristics of the drainage area with higher sanitary sewerage. In addition, the difference in removal efficiency according to the influent quality of the wet season and dry season was small.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.1
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• pp.11-19
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• 2016

Excessive application of nutrient supplement on the upland soil may increase the amount of discharge to surrounding water systems. The chemical fertilizer (CF), cow manure compost (CMC), and pig manure compost (PMC) are used as a nutrient supplement for cultivation of red pepper. Rice straws are widely used as a soil covering material in order to reduce weed occurrence, to protect soil moisture, and to supply organic matter in upland soil. This study was conducted to evaluate the furrow covering effect with rice straw on nutrient discharge in upland soil used for red pepper cultivation. The experimental plots of nutrient supplement were consisted of CF, CMC, and PMC and the amount of nutrient application were as recommended amount after soil test for red pepper cultivation. Each nutrient supplement treatment plot has no furrow covering (CFC) as a control and furrow covering with rice straw (FCS), respectively. Furrow covering with rice straw (FCS) of CF treatment and CMC treatment reduced the amount of T-N(total nitrogen) discharge by $1.4kg\;ha^{-1}$, $2.1kg\;ha^{-1}$, respectively, compared to control. While the amount of T-P(total phosphorus) discharge of the furrow covering with rice straw of CF, CMC, and PMC increased by $2.1kg\;ha^{-1}$, $2.1kg\;ha^{-1}$, and $0.2kg\;ha^{-1}$, respectively, compared to control. The phosphorus and nitrogen content of straw were 0.4 % and 0.3 % respectively. In addition, in three week the phosphorus was eluted from the straw which soaked in distilled water. Thus, it was assumed that T-P discharging originated from rice straw which applied as a furrow covering material. The furrow covering with rice straw reduced weed occurrence compared to control. But production of fresh red pepper was not influenced significantly by furrow covering with rice straw. In conclusion, excessive furrow covering with rice straw could induce T-P discharge from upland soil used for red pepper cultivation. Further studies are needed to evaluate the appropriate amount of rice straw as a furrow covering material.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.2
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• pp.85-94
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• 1997

The study is aimed to find out the causes of rapidly increasing chloride (Cl$^{－}$) concentration of the Samyang 3rd pumping station originated from coastal springs of Cheju since January 1996. The study results show that it was caused by following complicated natural and anthropogenic effects. Due to severe draught in 1996 with total rainfall of only 41.7% of annual mean of the last 36 years (1991 to 1995), it creates firstly), significant decrease of the spring discharges as well decline of the groundwater level at the site . Sea water level was in general 4.4 cm to 12.4 cm higher than the groundwater level of the site during 2 to 3.8 hours at each high tide. Those higher potential head of sea water motivates the sea water intrusion into the fresh water lens through the permeable clinkers and fracture zones situated beneath the existing grouted zone which was installed to a maximum 10 m below the ground water surface, The repeated expansion and contraction of the fresh water lens occurred by periodic changes of the sea water level at high and low tide accelerates secondly the enlargement of the transition zone between the fresh and sea water at the site. The decrease of recharge amount by rainfall shortage creates thirdly the reverse flow at the interface of sea water and groundwater. The repeated groundwater extraction of 2790${\pm}$450 $m^3$d$^{－1}$ at the time of low tide, when the fresh water lens of the sire is under the contraction stare, makes additional drawdown of the ground water level and induces the upconing of salt water into the fresh water lens. The duration of spring discharge whose Cl concentration is less than 150 mg/1 at the low tide measured at the nearby springs was about two hours with discharge rate of 532 $m^3$d$^{－1}$ and after that Cl$^{－}$ concentration is increased up to more than 1900 mg/ι.eased up to more than 1900 mg/L.

• Journal of The Korean Society of Grassland and Forage Science
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• v.3 no.2
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• pp.67-76
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• 1983

This experiment was carried out to investigate the effects of the different nitrogen rates and cutting heights on the dead stubble after cutting, and the carbohydrate reserved in stubble of sorghum-sudangrass hybrid (Sorghum bicolor (L.) Moench) Pioneer 988. The experiment was undertaken in the Experimental Livestock Farm of Agriculture Coll., Seoul Nat'l Univ. In Suweon, 1981 and 1982. The results obtained are summarized as follows: 1. The dead stubble after cutting was found to be great with high rate of nitrogen fertilizer and low cutting height. It was also learned that the rainfall during forage cutting period made the dead stubble increased. 2. A significant higher (p<0.05) carbohydrate reserves in the stubble was observed in the high stubble height at the first cutting time and 6th through 7th day after the first cutting. The results indicate that the high stubble height reserves more carbohydrate for the early regrwoth stage after the first cutting when comparing with the low stubble. 3. The content of carbohydrate reserves was influenced by climete. Drought is caused to high content of carbohydrate, whereas, rain is caused to low content of that. The critical soluble carbohydrate content causing the death of stubble supposed to be 3 to 6% at least. 4. It is suggest that carbohydrate reserves in plant do not play a distinctive role for the regrowth in a summer annual forage like sorghum-sudangrass hybrid, but it might be rather influenced by the other factors, for example, environmental conditions at harvest and new bud.

• Tuberculosis and Respiratory Diseases
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• v.53 no.3
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• pp.275-284
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• 2002

Background : Gemcitabine is a new anti-cancer agent for treating non-small cell lung cancer. Functioning as an antimetabolite, it induces anti-cancer effects by suppressing DNA synthesis after being incorporated into the DNA as a cytosine arabinoside analogue. When Gemcitabine is incorporated into the DNA, the p53 gene may be activated by induction of the DNA defect. However, there are a few studies on the molecular mechanisms of Gemcitabine-induced cell death. This study examined the role of p53 in Gemcitabine-induced cell death. Methods : A549 and NCl-H358 lung cancer cells were used in this study. The cell viability test was done using a MTT assay at Gemcitabine concentrations of 10nM, 100nM, 1uM, 10uM and 100uM. A FACScan analysis with propium iodide staining was used for the cell cycle analysis. Western blot analysis was done to investigate the extent of p53 activation. For the functional knock-out of p53, stable A549-E6 cells and H358-E6 cells were transfected pLXSN-16E6SD which is over expresses the human papilloma virus E6 protein that constantly degrades p53 protein. The functional knock out of p53 was confirmed by Western blot analysis after treatment with a DNA damaging agent, doxorubicine. Results : Gemcitabine exhibited cell toxicity in dose-dependent fashion. The cell cycle analysis resulted in an S phase arrest. Western blot analysis significant p53 activation in time-dependent manner. Gemcitabine-induced cytotoxicity was reduced by 20-30% in the A549-E6 cells and the 30-40% in H358-E6 cells when compared with the A549-neo and H358-neo control cells. Conclusion : Gemcitabine induces an S phase arrest, as expected for the anti-metabolite, and activates the p53 gene, Furthermore, p53 might play an important role in Gemcitabine-induced cell death. Further investigation into the molecular mechanisms on how Gemcitabine activates the p53 gene and its signaling pathway are recommended.

• Clean Technology
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• v.26 no.2
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• pp.151-157
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• 2020

Rapid urbanization has elevated the risk of urban flooding due to the increase in the impervious surface, causing environmental disasters and environmental pollution problems, such as lowering the groundwater level and increasing water pollution. In Korea, low impact development (LID) techniques have been introduced to minimize these environmental impacts and maintain the water cycle soundness. However, most small-scale development projects are in blind spots because there is no legal basis for rainfall runoff management. Small-scale development projects that increase the surface runoff of rainwater are required to mandate the application of LID facilities in accordance with the polluters' responsibility principle. Therefore, it is necessary to implement a preliminary consultation system for water cycle recovery. This study focuses on the cost-benefit analysis on the application of LID techniques for small-scale development projects. The scale of nationwide small-scale development projects used for cost-benefit analysis were defined as buildings with a land area of more than 1,000 ㎡ or a total floor area of 1,500 ㎡. As a result of analyzing the cost-benefits from the installation of LID facilities, they were found to be much lower than the economic standard value of 1. This might be due to the high cost of facilities compared to the scale of the project. However, considering the overall environmental value of improving the water environment and air quality by the installation of LID facilities and the publicity of reducing the operating cost of sewage treatment facilities, the introduction of a prior consultation for small-scale development projects is inevitable. In the future, institutional and financial support from local governments is required to improve the cost-benefits with the introduction of a prior consultation for small-scale development projects.