• 한국물환경학회지
• /
• 제24권6호
• /
• pp.659-669
• /
• 2008

Two sets of four parallel activated sludge reactors (ASRs) maintaining an MLSS of 3000 mg/L were operated to investigate the effect of DO, HRTs and bio-contact media (BCM) packing ratios on the removal efficiency of organic matters and nitrogen. Packing ratios of BCM to BCM-ASR systems 1, 2, 3, and 4 were 0% (suspended growth only), 10%, 15% and 20%, respectively. All systems were operated at an HRT of 4 hr, 6 hr, and 8 hr, respectively; DO concentration was maintained 0.5~1.0 mg/L and 1.5~2.0 mg/L for each HRT condition. In terms of TSS, TCODcr and SCODcr removal efficiency, all systems had a similar level of the removal efficiency under varied HRTs, and DO. But organic removal efficiency of systems with BCM was approximately 3~5% higher than systems without BCM at the same HRT and the DO. About the nitrification efficiency, with high DO (1.5~2.0 mg/L), as HRT (4 hr, 6 hr, 8 hr) or BCM packing ratio increased, the slight increment of nitrification efficiency was observed. However, under the low DO (0.5~1.0 mg/L), increase of BCM packing ratio and HRT resulted in large increase of the nitrification efficiency. At the same HRT and BCM packing ratio, the nitrification efficiency increased greatly with up to 15% as DO increased. When the HRT increased from 4hr to 8hr, the denitrification efficiency slightly increased by 5~10% only, under all DO conditions. Systems with BCM had higher denitrification efficiency, ranged 62.7~91.1% than systems without BCM showed 32.1~65.6%. And the increase in BCM packing ratio from 10% to 20% resulted in about 14~16% denitrification efficiency increment. BCM packing ratio showed great effect on the denitrification. The increase of the DO (from 0.5~1.0 mg/L to 1.5~2.0 mg/L) at the same HRT and BCM packing ratio resulted in slight decrease of denitrification efficiency with up to 7% for systems with BCM. But for systems without BCM, the denitrification efficiency decreased with up to 28%. In all system, the denitrification efficiency had more influence on the TN removal efficiency than nitrification efficiency. So, BCM packing ratio (0%, 10%, 15%, 20%) has greater effect on the TN removal than HRT and DO. The TN removal efficiency increased as packing ratio of BCM increased with up to 45%. As a result, the highest TN removal efficiency was observed 73.7% at the condition showed the highest denitrification efficiency that DO of 0.5~1.0 mg/L, an HRT of 8 hr, and 20% of BCM packing ratio was maintained.

• 한국작물학회지
• /
• 제45권2호
• /
• pp.103-107
• /
• 2000

The viviparity of 28 rice varieties was tested at 25 days after heading(DAH), 35DAH, and 45DAH in the laboratory and field condition for 12 days. The incubation temperature was 20/l$0^{\circ}C$ (day/night), 25/15$^{\circ}$C$ and 30/20$^{\circ}$C$ in the laboratory test, and under field water conditions in the field test. The biggest varietal difference of viviparity was found in the laboratory test when examined at 45DAH with the 6-day incubation under 25/15$^{\circ}$C$ . At this conditions the mean viviparous ratio was 32.1 % with the range of 53.9 and the variance of 259.5. In the field test, the significant varietal difference in the viviparity was also found in the lodging treatment at 45 DAH for 6 days. Correlation coefficient analysis between the field and laboratory tests was highly significant from 4 days after incubation at 45 DAH and after 6-day incubation at 35 DAH, and correlation coefficient was higher as incubation days in the laboratory and submerged days under field water became longer. Considering the correlation between the field and laboratory tests, varietal difference of viviparity and convenience of testing, the laboratory test at 45 DAH for 6-day incubation under 25/15$^{\circ}$C$ was the most efficient evaluation method for the viviparity of rice cultivar.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제39권2호
• /
• pp.60-66
• /
• 2019

This study was carried out to investigate the development and oviposition characteristics of Protaetia brevitarsis fed mulberry fermented sawdust added with mulberry cake. The results of rearing of P. brevitarsis larvae on oak fermented sawdust and mulberry fermented sawdust added with different ratio of mulberry cake, the development periods of larvae feed sawdust with mulberry cake were about 41.6~48.5 days and shortened by 117 or more than that without treatment. The development periods were shorter as the ratio of mulberry cake added increased and there was no difference according to the kind of sawdust. But the weight of the larvae raised in mulberry fermented sawdust added with mulberry cake was heavier than that of the larvae raised in oak fermented sawdust added with mulberry cake. When mass rearing P. brevitarsis larvae in oak fermented sawdust, the addition of 5% mulberry cake was appropriate. Also, the average number of laying eggs of female who fed diet with mulberry cake was 12.3% higher than that of untreated.

• 제어로봇시스템학회논문지
• /
• 제14권8호
• /
• pp.752-759
• /
• 2008

In this paper, we propose a high accurate geo-location system based on a single base station, where its location is obtained by Time-of-Arrival(ToA) and Direction-of-Arrival(DoA) of the radio signal. For estimating accurate ToA and DoA information, a MUltiple SIgnal Classification(MUSIC) is adopted. However, the estimation of ToA and DoA using MUSIC algorithm is a time-consuming process. The position tracking bias is occurred by the time delay caused by the estimation process. In order to mitigate the bias error, we propose the estimation method of the position tracking bias and compensate the location error produced by the time delay using the position tracking bias mitigation. For accurate self-localization of mobile robot, the Unscented Kalman Filter(UKF) with position tracking bias is applied. The simulation results show the efficiency and accuracy of the proposed geo-location system and the enhanced performance when the Unscented Kalman Filter is adopted for mobile robot application.

• 건축역사연구
• /
• 제19권1호
• /
• pp.7-26
• /
• 2010

This study is on Yun Seon Do's site located at Bogildo, Wando-gun, Jeonnam, compares the relics found through excavation to literature records and examines the character of relics and architectural features of the site. The results of this study are summarized as follows. First, bridge and pond including Goksudang and Seojae mentioned in related literatures were found around Goksudang. In the spatial composition, the area was divided into three using the stream from the valley and pond including buildings was built at each area. Each area was connected through Honggyo, Yueuigyo, and Ilsamgyo bridges and intentionally lengthened movement was considered as the space production technique to see the valley, and upper and lower pond. Second, 11 building relics, pond and fence were confirmed around Nakseojae. The transformative process of these relics could be divided into three periods. The 1st of these period was when Yun Seon Do lived there and Mumindang, pond and waterway were arranged as straight axis. Third, Dongcheonseoksil consisted of building relics (1) for preparing for and drinking tea and pavilion (building relics(2)) and pond, and these were static with nature and used as contemplative space for viewing.

• 해양환경안전학회지
• /
• 제14권1호
• /
• pp.65-69
• /
• 2008

현재 완도항은 인근해역을 통항하는 선박이 황천을 만났을 때 피항할 수 있는 묘박지의 부족으로 항만 안전에 많은 위험요소가 내재하고 있다. 이러한 문제점을 해결하기 위하여, 본 연구에서는 완도항 인근 해역의 지리적인 조사를 하여, 피항 정박지의 최적지를 제안하고자 하였다. 정박지 제안을 위하여, 인근 해역의 어장 조사를 실시하여 정박지 부근의 어장위치 등을 조사하여, 위해 요소를 분석하였다. 또한 통항선박과의 안전관계를 위하여, 해상교통조사를 실시하였으며, 이를 정박지 지정에 반영하였다. 이를 바탕으로 최적 정박지를 후보지로 제안하였다.

• 대한지역사회영양학회지
• /
• 제15권5호
• /
• pp.687-693
• /
• 2010

This study investigated difference of general eating habit and eating-out behavior between men and women of university students in Gyonggi area. The survey was conducted from 1 March to 1 April 2010, in Gyeonggi area. Self-administered questionnaires were collected from 250 students in Gyeonggi area. The research results show, first of all, that they eat twice a day, and they usually do not eat breakfast. The main reason why they do not eat breakfast is that they do not have enough time to eat. Between men and women, there is significant difference in eating amount and eating speed at 0.001 levels. Men's problems of eating behavior are irregular meal time and speed of eating time, and in case of women, they do not have a meal regularly and overeat at one time. Second, they usually eat out for a meal and gather with friends once to three times a week. Also, the lunch set-menu promotion is the most preferred one. Third, when men choose a restaurant, they consider in order of taste, convenience, amount, and service; women consider in order of atmosphere, taste, convenience, and service. Taste is the most important for men; atmosphere is the most important consideration for women. Taste (at 0.01 levels), sanitation (at 0.05 levels), and atmosphere (at 0.001 levels) are significantly different between men and women in choosing restaurant.

• 한국응용과학기술학회지
• /
• 제27권2호
• /
• pp.183-187
• /
• 2010

Core-Shell polymers of silicone dioxide-styrene system were prepared by sequential emulsion polymerization. In inorganic/organic Core-Shell composite particle polymerization, silicone dioxide adsorbed by surfactant sodium dioctyl sulfosuccinate (EU-DO133L) was prepared initially and then core silicone dioxide was encapsulated emulsion by sequential emulsion polymerization using styrene at the addition of potassium persulfate (KPS) as an initiator. We found that $SiO_2$ core shell of $SiO_2$/styrene structure was formed when polymerization of styrene was conducted on the surface of $SiO_2$ particles, and the concentration sodium dioctyl sulfosuccinate (EU-DO133L) was 0.5~2.0g. The structure of core-shell polymer were investigated by measuring to the thermal decomposition of polymer composite using thermogravimetric analyzer and morphology of latex by scanning electron microscope(SEM).

• 한국통신학회논문지
• /
• 제34권9A호
• /
• pp.664-672
• /
• 2009

본 논문에서는 원형 등간격 어레이를 갖는 이동 릴레이를 위한 셀 탐색과 입사각 동시 추정기법을 제안한다. 제안된 셀 탐색과 입사각의 동시 추정기법은 인접 기지국에서 이동 릴레이로 수신되는 신호간에 심볼 타이밍 옵셋이 존재하는 경우에도 강건한 특성을 갖고, 셀 탐색과 입사각을 각각 독립적으로 추정하는 경우에 비하여 계산량과 수행시간을 감소시킬 수 있다. 제안된 동시 추정기법의 성능을 Mobile WiMAX 환경 하에서 모의실험을 통하여 검증한다.

• 전기학회논문지
• /
• 제67권9호
• /
• pp.1202-1209
• /
• 2018

This paper is concerned with the problem of setting controller's parameters when applying the intelligent PID (i-PID), which has recently been proposed and had many successful results, to the two-degree-of-freedom (2DoF) PID controller structure. Generally, the parameter settings of conventional PID controllers are known to be quite difficult and be dependent on the characteristics of the plants. In addition, it is less known how the two 2DoF parameters are set up for the improvement of transient characteristics. Here, we are going to present one of the criteria for parameter setting in the case of using a 2DoF i-PID, by evaluating the error signals to the set-point and disturbance. That is, we first, obtain parameters of i-PID by optimizing the disturbance responses, and then determine two parameters of 2DoF component through optimizing set-point response. The standard values of all parameters are calculated for the 7 types of test batches and rounded up as a table.