• Journal of the Korean Geosynthetics Society
• /
• v.14 no.4
• /
• pp.79-86
• /
• 2015

Korean territories has formed about 70% of mountainous areas that have acidified serious level to average pH 4-5. There are a number of abandoned metal mines about 1,000 in Korea. However, mine tailings and waste rock included heavy metals are exposed to long-term environment without prevention facility or treatment system. Thus, ongoing management and monitoring of soil environment are required. Most of abandoned mine scattered in forest areas of slopes. Soil erosion due to continuous rainfall in the slopy areas can cause the secondary pollution by the influence eutrophication of water system and the productivity loss of the plant. Therefore, this study would like to estimate pH leaching rate by artificial rainfall using waste neutralization-agent in lysimeter. Moreover, the potentially of secondary pollution related to precipitation is figured out through the experiments, and the optimal planting methods would examinate after neutralizing treatment in soil. Experiments composed three kinds of lysimeter; lysimeter 1 had filled only acidic soil, lysimeter 2 had neutralized soil, and lysimeter 3 had planting plants after neutralized soil. In the results, lysimeter 2 showed the lowest pH leaching, and there is not specific relativity with pH leaching of the seasonal characteristics.

• Applied Chemistry for Engineering
• /
• v.5 no.5
• /
• pp.862-870
• /
• 1994

$Pb(NO_3)_2$, $Mg(NO_3)_2$ and $NbCl_5$ were used as starting materials and made into solutions. For $Pb(Mg_{1/3}Nb_{2/3})O_3$ composition, each solution measured was mixed and heated to $70^{\circ}C$ to resolved $PbCl_2$ precipitated at lower temperature coprecipitates were formed by adding oxine and ammonia gas under pH ranging 8 to 10, and the prepared coprecipitates were filtered and washed by distilled water. The $Pb(Mg_{1/3}Nb_{2/3})O_3$ powders were synthesized by calcination of coprecipitates at the temperature range of $700^{\circ}C$ to $1000^{\circ}C$, for 5hr. The average particle size of the synthesized powders showing spherical shape was $0.3{{\mu}m}$. The powders were formed to make pellets under pressure of $2000Kg/cm^2$, and the formed pellets were sintered at the temperature range of 1100 to $1200^{\circ}C$, for 5hr. The speciman sintered at $1200^{\circ}C$ showed theoretical density of 97.4%, dielectric constatnt of 17000 at 1kHz, and dielectric loss of 0.02% at 1kHz

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.303-303
• /
• 2017

Japanese agriculture has faced to several threats: aging and decrease of farmer population, global competition, and the risk of climate change as well as harsh and variable weather. On the other hands, the number of large scale farms is increasing, because farm lands have been being aggregated to fewer numbers of farms. Cost cutting, development of efficient ways to manage complicatedly scattered farm lands, maintaining yield and quality under variable weather conditions, are required to adapt to changing environments. Information and communications technology (ICT) would contribute to solve such problems and to create innovative technologies. Thus we have been developing an early warning and decision support system to reduce weather and climate risks for rice, wheat and soybean production in Japan. The concept and prototype of the system will be shown. The system consists of a weather data system (Agro-Meteorological Grid Square Data System, AMGSDS), decision support contents where information is automatically created by crop models and delivers information to users via internet. AMGSDS combines JMA's Automated Meteorological Data Acquisition System (AMeDAS) data, numerical weather forecast data and normal values, for all of Japan with about 1km Grid Square throughout years. Our climate-smart system provides information on the prediction of crop phenology, created with weather forecast data and crop phenology models, as an important function. The system also makes recommendations for crop management, such as nitrogen-topdressing, suitable harvest time, water control, pesticide spray. We are also developing methods to perform risk analysis on weather-related damage to crop production. For example, we have developed an algorism to determine the best transplanting date in rice under a given environment, using the results of multi-year simulation, in order to answer the question "when is the best transplanting date to minimize yield loss, to avoid low temperature damage and to avoid high temperature damage?".

• Journal of Wetlands Research
• /
• v.20 no.2
• /
• pp.181-189
• /
• 2018

This study was performed to analyze the dynamics and distributional condition of biological community and to support the basic information about the estuarine ecosystem management by using the intensively surveyed results by each taxon experts around Tamjin river. We analyzed the biological diversity, abundance, correlation among species, and ecological characteristics about 11 taxa groups including vegetation, fish, birds, mammals, etc. in the Tamjin river estuarine ecosystem. We classified vegetation types into 7 physiognomic types and 18 communities according to habitat conditions with the physical environments and salinity. In total, 1125 species including 9 species of endangered species were identified in research area. The species composition and distributional characteristics of each taxon were corresponded to the environmental characteristics of the estuarine ecosystem. Especially, the species diversity and distribution were clearly distinguished in the river according to the difference of the environmental factors such as flow rate, salinity, and soil. Despite the disturbance factors such as barrage and levees, the biodiversity and its distribution were evaluated to be high level under the current environmental conditions. However, loss or reduction of wildlife habitat due to reclamation, embankment, barrage installation and expansion of farmland has been identified as a major threat to the diversity and health of the local ecosystem. The results of this study can be used as a basic data to cope with various development pressure and damage crisis of the whole estuaries including Tamjin river.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.13 no.3
• /
• pp.198-205
• /
• 2010

The purpose of this study is to investigate the characteristics of the grain size distribution and organic matters to understand the current status of the tidal flat sediment for efficient management of Suncheon Bay. We investigated the characteristics of the surface sediments in the mouth area of the Suncheon Bay at fifteen stations in April and July, 2009. Specific conclusions were as follows. The sediments in the most part of tidal flat was shown as muddy facies(clay and silt contents was more than 90%), whereas in the tidal river affected by water flow from the Dongstream was shown as sandy facies. The analyzed values of the tidal flat sediment were in the range of $1.9{\sim}3.8{\phi}$(mean $2.5{\phi}$) for sorting, and -1.5~3.2(mean -0.3) for skewness, and 1.5~14.1(mean 3.9) for kurtosis. So we knew that the tidal flat sediments in the Suncheon Bay was mainly composed by fine-grained sediment. Erosion was happened in the tidal river, whereas sedimentation was occurred in the tidal flat. The most of organic matters was derived from the Dongstream. Total organic matters shown as ignition loss was 5.75%, COD and $H_2S$ values were lower than the eutrophication level(COD; 20.0 mg/g dry, $H_2S$; 0.2 mg S/g dry). From our research the tidal flat of the Suncheon Bay is relatively fine, but a part of the flat was exceed the environmental standard. So we have to establish effective countermeasures to reduce the organic matters and nutrients derived from stream for environmental preservation of the Suncheon bay and conduct scientifically sustainable monitering for streams flowing into Suncheon Bay and tidal flat.

• Food Science of Animal Resources
• /
• v.32 no.1
• /
• pp.112-117
• /
• 2012

In order to improve or replace the direct addition method of nitrite and ascorbic acid, the effect of nitrite and ascorbic acid-derived gas addition on color development and physical characteristics in emulsified sausage was investigated. Nitrite (150 ppm) and ascorbic acid (450 ppm) were added directly to emulsion in the control group, but in the treatment group nitrite and ascorbic acid-derived gas was used for emulsion. In the control and treatment groups, pH values were higher than raw meat, but these values did not show significant change during the storage in both groups. In the meat color, lightness (CIE $L^*$) and redness ($a^*$) values of control and treatment groups were higher compared to raw meat. The treatment group has lower redness and higher yellowness ($b^*$) values than control group during the storage (p<0.05). However, lightness was not significantly different between control and treatment groups. The cook and storage loss values were significantly different between control and treatment groups (p<0.05), but the water holding capacity and shear force values were not significantly different between groups. These results showed that treatment of nitrite and ascorbic acid-derived gas has a similar effect to direct addition of nitrite and ascorbic acid on color development and physical characteristics in emulsified sausage. Also, these results showed that nitrite and ascorbic acid-derived gas addition may be a good possible alternative of nitrite and ascorbic acid using in emulsified sausage.

• Korean Journal of Veterinary Service
• /
• v.31 no.1
• /
• pp.161-166
• /
• 2008

Deep pectoral myopathy (DPM), also known as Oregon muscle disease or green muscle disease, was first described in 1968 by Dickinson et al as "degenerative myopathy" in turkeys. Even though this condition was first recognized in adult meat-type turkey and chicken breeders, it is becoming more and more common in meat-type growing birds. DPM occurs exclusively in birds that have been specially selected for breast muscle development. It is generally recognized that DPM is an ischemic necrosis that develops in the deep pectoral muscle (supracoracoideus or pectoralis minor muscle) mainly because this muscle is surrounded by inelastic fascia and the sternum, which do not allow the muscle mass to swell in response to the physiological changes occurring when muscle are exercised, as in wing flapping. The lesion does not impair the general health of birds and is generally found during cut-up and deboning, moreover, it can be both unilateral or bilateral, affecting just one or both pectoralis minor muscle, respectively. No public health significance is associated to DPM, but it is aesthetically undesirable. The fillet should be removed, whereas the rest of the carcass is still fit for human consumption. However, the required trimming operations determine the downgrading of the products and produce an economic loss for the industry, especially because it affects the more valuable part of the carcass. The incidence of DPM increases with market weight in broilers, with more cases reported in higher-yielding strains and in males. Increased bird activity (flock nervousness, flightiness, struggle, and wing flapping) induced by factors such as feed or water outages, lighting programs and intensity, human activity, and excessive noises in and around chicken houses should be looked at as a trigger for the development of DPM in broiler. However, most of the studies conducted to evaluate the incidence of DPM in poultry are concerned with parental commercial breeding stocks under experimental conditions (Bianchi et al. 2006. Poult Sci 85 : 1843-1846). There is a possible genetic relationship between the selection for large-breasted birds and this condition. Management procedures that discourage excessive wing flapping would reduce the incidence (Jordan and Pattison. 1998. Poultry diseases. 398-399).

• Journal of Life Science
• /
• v.27 no.9
• /
• pp.1086-1095
• /
• 2017

There is growing interest in groundwater resources to overcome the loss of surface water resources due to climate change. An understanding of the microbial community of aquifers is essential for monitoring and evaluating groundwater contamination, as well as groundwater management. Most microorganisms that inhabit aquifer ecosystems are attached to sediment particles rather than planktonic, as is the case in groundwater. Since sampling aquifer sediment is not easy, groundwater, which contains planktonic microorganisms, is generally sampled in microbial community research. Although many studies have investigated microbial communities in contaminated aquifers, there are only a few reports of microbial communities in uncontaminated or pristine aquifers, resulting in limited information on aquifer microbial diversity. Such information is needed for groundwater quality improvement. This paper describes the ecology and community structure of groundwater bacteria in uncontaminated aquifers. The diversity and structures of microbial communities in these aquifers were affected by the concentration or distribution of substrates (e.g., minerals, organic matter, etc), in addition to groundwater characteristics and human activities. Most of the microbial communities in these uncontaminated aquifers were dominated by Proteobacteria. Studies of microbial communities in uncontaminated aquifers are important to better understand the biogeochemical processes associated with groundwater quality improvement. In addition, information on the microbial communities of aquifers can be used as a basis to monitor changes in community structure due to contamination.

• Korean Journal of Soil Science and Fertilizer
• /
• v.34 no.1
• /
• pp.55-63
• /
• 2001

N fertilizer recommendations to optimize with consideration to maximum crop yields, maximum profits, and minimum N losses to ground or runoff water, an advisory system. Nitrogen Expert System (NES), was developed. The system was to estimate the optimal rate of N fertilizer application cornfields in Illinois. NES was constructed using Smart Elements, a knowledge-based system that manages the expertise of human experts. NES was reinforced by addition of the effect of a productivity index (PI), soil organic matter content (SOM), and pre-sidedressing of nitrate concentration (PSNT) to the optimal N fertilizer recommendation. NES contains 49 rules, 1 class, 14 objects, and 2 properties. NES was successfully operated, showing N recommendations with inputs of three soil properties including PI, SOM, and PSNT. NES can reduce N loss to the environment, but adherence to the recommendations may also reduce farmers income. Therefore, NES will be more effective by evaluating both environmental damage assessment and other economic agricultural management parameters and other soil physico-chemical parameters.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.37 no.3
• /
• pp.171-176
• /
• 2021

Pneumomediastinum is a very rare and potentially catastrophic complication of dental procedures. Its common causes are tooth extraction, endodontic treatment, and subgingival curettage using handpieces and high-pressure air/water syringes. We present a case of massive pneumomediastinum with subcutaneous emphysema in a 61-year-old female who underwent bone grafting into the maxilla for pretreatment of dental implantation using a syringe. The patient suffered from abrupt severe odynophagia and loss of consciousness. The patient transferred to emergency department and images work-up revealed a pneumomediastinum and subcutaneous emphysema on the entire face and neck. We performed conservative treatments including prophylactic antibiotics, oxygen inhalation, and fasting meals, and then discharge after 7 days uneventfully. The patient's syncope might be resulting from hypotension and pain shock induced by pneumomediastinum with a sudden chest compression. The pneumomediastinum could be resulting from concurrent perforation and massive air infiltration into the maxillary sinus during bone grafting. We suggest that pneumomediastinum needs prompt diagnosis and management because of the risk of airway obstruction when a patient present syncope in the dental room.