Songji lagoon, one of the major lagoons located along the East coast, is considered to be worth preserving because of its good water quality. To consider ways to manage the water quality of Songji lagoon, this study was conducted by employing the analysis technique for system analysis of the water quality model. This study used WASP model which is a model with hydraulic part and water quality part combined. The model for Songji lagoon used the same value as the coefficients of water quality reaction used for Hwajinpo model. And it was revised and verified with the water quality measured in Songji lagoon. The spatial concentration of water quality of Songji lagoon and Hwajin po exhibited different distribution respectively, yet showing a similar characteristic in physical and water side structure. The major water quality items used in system analysis are BOD, limiting nutrients (N, P). The principal conditions reflected the system analysis are an increase or decrease of Allochthonous pollution load and removal of sediment. The study results show that the water quality of Songji lagoon is considerably changed more in sediment than Allochthonous pollution load. Especially, the management of Nonpoint pollution due to a temporary rainfall is more important among allochthonous pollution load.

유류를 포함한 HNS의 물동량이 증가 추세에 있음에도 불구하고, 우리나라에서는 HNS 해상운송 중에 발생한 사고의 분석과 위험에 관한 연구가 미진하다. HNS는 형태와 종류가 다양하고 사고발생시 피해가 심각하게 나타난다. 액체화물운반선(유조선, 케미컬탱커선, 액화가스탱커선 등)의 사고에 대한 원인을 분석하고 위험성에 대한 연구가 필요하다.

본 연구에서는 서로 다른 터치스크린용 Ag pastes를 스크린 인쇄 방식으로 ITO film 위에 전도성 패턴을 형성하고 10장씩 인쇄하여 130℃ 10분 동안 건조 하였다. 여기서 130℃ 10분의 건조 조건은 ITO film의 열화가 발생하지 않는 조건이다. 신뢰성 테스트는 염수테스트와 고온고습테스트를 진행한다. 각 테스트는 2장씩의 전도성 패턴 상태를 확인한다. 전도성 패턴을 침적 시킨 염수(NaCl 5% 녹인 증류수)를박스형 열풍 건조기(35℃)에서각 24, 48, 72시간 마다 상태를 확인하고 고온고습기(60℃ 90%)에서는 각120, 240시간 마다 상태를 확인하였다. 이런 신뢰성 테스트를 통해 서로 다른 Ag pastes의 접착력, 전도성의 변화 등을 알 수 있어 품질 저하를 막을 수 있고, 신뢰성 테스트에서 표면의 산소함량이 많은 Ag paste는 변색이 빨리 올 수 있음을 알 수 있었다.

Chromated Copper Arsenate (CCA)-treated wood has been widely used in Korea since 1980s, but the release of chromium, copper, and arsenic from the wood has been reported to cause environmental contamination. This study was aimed at investigating the environmental impact of brook water and sediment from the construction of cylindrical wood piles around a brook (partially immersed in the water) and wood bridge structures over the brook. Ten water and ten composite sediment samples (including one control for each) were collected from sites where a large number of treated wood structures were installed. Samples were analyzed for total chromium, copper, and arsenic using atomic absorption spectroscopy. Water contamination was not observed in all samples, but metal concentrations in the sediment samples were elevated at most sites, indicating the accumulation of metals in the sediment. This study suggested that the use of CCA-treated wood by continuos contact with water can lead to marked leaching of metal components and may ultimately cause health effects on aquatic organisms living on or in the sediment.

The purpose of this study is to analyze the effectiveness of process approach for business performance of a company certified with ISO 9000 : 2000 quality management system. The result of this empirical research were identified as follows. Documentation a

The first Korean satellite laser ranging (SLR) system, Daedeok SLR station (DAEK station) was developed by Korea Astronomy and Space Science Institute (KASI) in 2012, whose main objectives are space geodesy researches. In consequence, Korea became the 25th country that operates SLR system supplementing the international laser tracking network. The DAEK station is designed to be capable of 2 kHz laser ranging with precision of a few mm both in daytime and nighttime observation of satellites with laser retro-reflector array (LRA) up to the altitude of 25,000 km. In this study, characteristics and specifications of DAEK station are investigated and its data quality is evaluated and compared with International Laser Ranging Service (ILRS) stations in terms of single-shot ranging precision. The analysis results demonstrated that the DAEK station shows good ranging performance to a few mm precision. Currently, the DAEK station is under normal operations at KASI headquarters, however, it will be moved to Sejong city in 2014 to function as a fundamental station for space geodesy researches in combination with other space geodesy systems (GNSS, VLBI, DORIS, etc.).

Trickling filter has been extensively studied for the domestic wastewater treatment especially for the small scale plants in rural area. The performance of the trickling filter depends on the microbial community and their activity in the biofilms on the media. Nitrification, denitrification, and phosphorus removal of the trickling filter from the wastewater depend on the activity and the amount of the specific microorganisms responsible for the metabolism. For the estimation of the performance of a trickling filter, batch nitrification experiment and fluorescence in situ hybridization (FISH) were carried out to measure the microbial activity and its distribution on the media of the trickling filter. Batch nitrification activity measurement showed that the top part of the 1st stage trickling filter had the highest nitrification activity and the maximum activity was 0.002 g NH4-N/g MLVSS․h. It is thought that higher substrate (ammonia) concentration yields more nitrifying bacteria in the biofilms. The dominant ammonia oxidizer and nitrite oxidizer in the biofilm were Nitrosomonas species and genus Nitrospira, respectively, by FISH analysis. Less denitrifiers were found than nitrifiers in the biofilm by the probe Rrp1088 which specifically binds to Rhodobacter, Rhodovulum, Roseobacter, and Paracoccus. Phosphorus accumulating bacteria were mostly found at the surface of the biofilm by probe Rc988 and PAO651 which specifically binds to Rhodocyclus group and their biomass was less than that of nitrifiers.

Sludge minimization from wastewater treatment plant is becoming more important to save disposal costs and to contribute to sustainable development. For the reduction of sludge production, solubilization and dewaterability of sludge are important factors in sludge processing. Ultrasonic treatment has been used to enhance sludge solubility and dewaterability with anaerobic digestion sludge, primary sludge, and activated sludge. At the ultrasonic power of 0.2 kW/L for 1 hour, anaerobic sludge and activated sludge showed higher solubilization efficiency than the primary sludge in terms of COD, proteins, and suspended solids. Ultrasonic treatment decreased sludge dewaterability and sludge settling characteristics up to 720 kJ/L of ultrasonic energy. In conclusion, ultrasonic treatment was effective for sludge solubilization but it deteriorate dewaterability (specific resistance) and settling characteristics (SVI) of sludge at the experimental conditions.

A strategic decision making on location selection for product transportation includes many tangible and untangible factors. To choose the best locations is a difficult job in the sense that objectives usually conflict with each other. In this paper, we consider a multi stage multi criteria transshipment problem with different types of items to be transported from the sources to the destination points. For the optimization of the problem, a goal programming formulation will be presented in which the location selection for each product type will be determined under the multi objective criteria. In the study, we generalize the transshipment model with a variety of product types and finite number of different intermediate nodes between origins and destinations. For the selection of the criteria we selected the costs(fixed cost and transportation cost), location numbers, and unsatisfied demand for each type of products in multi stage transportation, which are the main goals in transshipment modelling problems. The related conditions are also modelled through linear formats.

Although there can be some differences among varieties, the developmental rate of soybean (Glycine max) is mainly influenced by temperature and photoperiod. The objective of this experiment, that is the first step for creating phenology model of soybean, is to investigate the developmental characteristics under different temperature and day length conditions. Considering maturity, employed were five cultivars, Hwaeomputkong, Sinpaldalkong, Taegwangkong, Daewonkong, and Seoritae. They were sown at three different dates and grown under natural day length throughout growing season in 2008, while in another field they were subjected to longday of 16 hours by the supplemental lighting from July 6 to maturity. Developmental processes were investigated every five days after seeding. Days to flowering and final number of node increased in late maturiity cultivars. These traits decreased in delayed seeding, while increased under longday treatment. Even though there were some varietal differences in the slope of the line, V-stage(the number of nodes) of soybean consistently showed the linear relation(r2>0.95) with the sum of effective temperature from emergence to flowering. Daylength would be a cardinal factor that determines development including final number of node and duration of reproductive stage. However, it has not been figured out completely. Further studies will focus on the effect of temperature on reproductive stage and developmental response to daylength.