소양호의 (昭陽湖) 미생물 분포에 관한 요인분석에 관하여

안태석,김범철,조규송 ( Tae Seok Ahn,Bom Chul Kim,Kyu Song CHo ) 한국하천호수학회 1986 생태와 환경 Vol.19 No.3·4

The factor analysis was applied to scrutinize the effects of environmental factors on bacterial population in Soyang lake. For this purpose, total 294 cases of 18 physico-chemical and 2 bacterial parameters were observed. The major parts of the variance of the heterotrophic bacteria were interpreted as inorganic nitrogen and depletion of dissolved oxygen, and that of the psychrophilic bacteria was as depletion. of dissolved oxygen. But the season in summer and organic substance and phytoplankton blooming were minor factors for two bacterial population.

수생관속식물이 우점하는 호수에서 부유 세균과 부착세균 개체수의 계절적 변화

안태석,정미정 ( Tae Seok Ahn,Mi Jeong Jeong ) 한국하천호수학회 1996 생태와 환경 Vol.29 No.3

To find out the relationship between macrophyte and bacteria, the numbers of free-living bacteria and attached bacteria in two macrophytes dominant ponds were estimated weekly from May to August, 1995. The free-living bacterial numbers and attached bacterial numbers removed from macrophytes with stomacher were measured by the Acridine Orange Direct Count method. The free-living bacterial numbers were ranged 0.3x10^6∼2.3×1066 cells·ml^-1, and those were not correlated to chlorophyll a concentration. The maximum peak were appeared at flowering period. The attached bacterial numbers on N. tetragona, N. indica and A. calamus were ranged 2.4×10^6∼16.4×10^6 cells ·cm^-2, 10.6×10^6∼101.5x10^6cells ·cm^-2 and 2.3×10^6∼14.5x10^6cells ·cm^-2, respectively. The attached bacterial numbers of same pond were different from each host macrophyte. Just after the flowering period of each macrophyte, the attached bacterial number had maximum, which means that the bacterial community was affeced by the life cycle of macrophytes.

수생관속 식물이 우점하는 연못에서의 B - glucosidase 활성도 변화

안태석,정미정,최승익 ( Tae Seok Ahn,Mi Jeong Jeong,Seung Ik Choi ) 한국하천호수학회 1996 생태와 환경 Vol.29 No.4

For determing the ecological roles of free-living bacteria and epiphytic bacteria on marophytes (Acorus calamus, Nymphaea tetragona, Nymphoides indica), the β-glucosidase activities of free-living and attached bacteria were investigated at two ponds weekly from May, 1995 to August, 1995. The β-glucosidase activities of pond water of Yeonjeokji and Sesimjeong were ranged 35∼1073 nmol 1^-1 hr^-1 and 30∼898 nmol 1^-1 hr^-1, respectively. At Yeonjeokji, where the phytoplankton was abundance, the variations of β-glucosidase activity correlated with the chlorophyll a concentration, while at the Sesimjeong, where the macrophyte was abundance, the correlation between activity and chlorophyll a concentration was not appeared. The areal activity of A. calamus, N. tetragona, N. indica were varied 16∼437, 223∼149537 and 19∼2396 nM cm^-2 hr^-1, respectively. The lowest areal peaks of activities of three macrophytes were appeared during the flowering period. At Yeonjeokji, the specific activity of epiphytic bacteria on N. tetragona was higher than that of free-living bacteria during the late spring, but it was lower during the summer. In other hand, the specific activity of epiphytic bacteria on N. indica, was 200∼500 times higher than that of free-living bacteria. At Sesimjeong, variation of the specific activity of epiphytic bacteria on A. calamus was similar to that of free-living bacteria. These results suggest that bacterial mineralization rates are affected by the kind of macrophytes, their physicological state and limnological characteritics.

소양호에서의 Alkaline phosphatase 활성도의 Kinetics

안태석,김범철,조규송 ( Tae Seok Ahn,Bom Chul Kim,Kyu Song Cho ) 한국하천호수학회 1989 생태와 환경 Vol.22 No.3

The kinetics of alkaline phosphatase activity were studied at the surface of a warm monomictic large reservoir, Lake Soyang, every two months from February 1988 to June 1989. Three sampling stations were located at the dam site, near a large netcage-type fishfarm, and a tributary stream inlet region where the dinoflagellate blooming occurs in warm seasons. Vmax of alkaline phosphatase, showing the range of 0.02∼5.95 μM/1/hr, was high during the spring bloom, April and June, and low during the turnover time, October, December, and February. Kt+Sn, showing the range of 0.06 ∼31.0 μM/1, was high during the turnover time, which seems to be caused by the nutrients supply from the hypolimnion. Kt+Sn was much higher during turnover time at the fishfarm station than other stations, which is obviously resulting from the large amount of fecal deposition at the bottom and the diffusion of organic phosphorus upto the surface. It seems that at high density phytoplankton itself can be the substrate for alkaline phosphatase, since the peak time of Kt+Sn coincided with the peak of chlorophyll a concentration in the shallow stream inlet station where dinoflagellates aggregate.

터보등화를 이용한 직접대역확산통신 기반의 은밀 수중통신 성능분석

안태석,정지원,박태두,이동원,Ahn, Tae-Seok,Jung, Ji-Won,Park, Tae-Doo,Lee, Dong-Won 한국정보통신학회 2016 한국정보통신학회논문지 Vol.20 No.8

Researches for oceans are limited to military purpose such as underwater sound detection and tracking system. Underwater acoustic communications with low-probability-of-interception (LPI) covert characteristics were received much attention recently. Covert communications are conducted at a low received signal-to-noise ratio to prevent interception or detection by an eavesdropper. This paper proposed optimal covert communication model based on direct sequence spread spectrum for underwater environments. Spread spectrum signals may be used for data transmission on underwater acoustic channels to achieve reliable transmission by suppressing the detrimental effect of interference and self-interference due to jamming and multipath propagation. The characteristics of the underwater acoustic channel present special problems in the design of covert communication systems. To improve performance and probability of interception, we applied BCJR(Bahl, Cocke, Jelinek, Raviv) decoding method and the direct sequence spread spectrum technology in low SNR. Also, we compared the performance between conventional model and proposed model based on turbo equalization by simulation and lake experiment. 전송되는 정보들의 가로채기 확률을 감소시키기 위한 피감청 기술 중 대표적인 대역확산통신 기법을 적용함으로써 통신 성능에 미치는 영향을 분석하고, 이를 통해 최적의 은밀 수중음향통신 시스템의 모델을 제안한다. 대역확산 통신 된 신호의 레벨이 낮아져 주변의 배경소음과 같은 레벨로 전송하기 때문에 피탐지 확률이 감소하고 은밀성의 특징을 갖게 된다. 본 논문에서는 BCJR(Bahl, Cocke, Jelinek, Raviv) 복호방법과 대역 확산 기법 중 직접 수열 대역 확산 기법을 적용하였으며, 은밀 수중 통신에서 고려되는 송수신 모델은 크게 두 가지로 나뉘는데, 경판정 기반의 송수신 모델과 반복기반의 터보 등화 모델의 성능을 시뮬레이션과 호수 실험을 통해 성능을 비교 분석하였다.

소양호에서 세균군집 크기에 미치는 플랑크톤의 영향

안태석,정미정,이은주,조규송 ( Tae Seok Ahn,Mi Jeong Jeong,Eun Joo Lee,Kyu Song Cho ) 한국하천호수학회 1995 생태와 환경 Vol.28 No.2

To scrutinize the biological effects of plankton communities to bacterial community, the total bacterial numbers, chlorophyll a concentration and phytoplankton, zooplankton communities were analyzed in Lake Soyang from May 13, to July 14, 1994. At Om depth, total bacterial numbers positively correlated with chlorophyll a concentration. On the other hand, at 2m depth, the two parameters had negative correlation. At the middle of the June, when dominants of phytoplankton, zooplankton were changing, the bacterial numbers dropped down. These results suggest that as the Anabaena becoming dominant species, the some zooplankton species changed to bacterivore. The bacterial community was mainly effected by phytoplankton at Om, and by zooplankton at 2m depth.

인공 습지를 이용한 오수 정화 처리

안태석,Ahn Tae-seok 한국관개배수위원회 1997 한국관개배수논문집 Vol.4 No.2

한강상류 인공호에서의 미생물 분포와 활성도에 관하여

안태석,이동훈,김범철,조규송 ( Tae Seok Ahn,Dong Hun Lee,Bomchul Kim,Kyu Song Cho ) 한국하천호수학회 1988 생태와 환경 Vol.21 No.3

The values of total bacterial numbers, heterotrophic bacterial numbers, the proportions of specific enzyme releasing bacteria and microbial activities were measured in the five artificial reservoirs in North Han river. The values of total bacterial number ranged from 0.62 x 10E5 to 21.09 x 10E5 cells/ml, which is the common values in mesotrophic lakes. With the effect of civil construction at the upper region of the North Han river, the proportions of alpha-glucosidase-releasing bacteria were higher in Lake Paro and Lake Chuncheon. Beta-glucosidase proportions were high in Lake Paldang and showed high correlation with the concentration of chlorophylla. The alkaline phosphatase proportion were higher in Lake Paro, Lake Chuncheon and Lake Paldang. The turnover rate of acetate showed no relationship with any other trophic state index items, such as chlorophyll concentration, phosphate concentration and primary productivity. But the phosphatase activity showed high correlation coefficience, and it should be estimated as a trophic state index in these artificial reservoirs.

수중음향통신에서 BCJR 기반의 터보 등화기 실험 성능 분석

안태석(Tae Seok Ahn),정지원(Ji Won Jung) 한국항해항만학회 2015 한국항해항만학회지 Vol.39 No.4

수중 음향 통신은 과거 군사적 목적을 위해 제한적으로 사용되어졌으나, 수중 탐지, 운동체 추적, 잠수함, 부이를 이용한 해양의 날씨 변화 등 해양에서의 통신에 대한 연구가 활발히 이루어지며 활용 분야가 확대되고 있는 추세이다. 수중음향통신은 다중경로로 인한 신호간의 간섭으로 성능 및 전송율이 열약한 실정이다. 따라서 다중 경로 전달 환경인 수중음향통신에서 원활한 통신과 함께 수신 신호의 성능을 향상시키기 위하여 낮은 SNR에서도 우수한 성능을 보이는 채널 부호화 기법에 대해 연구하였다. 본 논문에서는 데이터 길이의 가변성이 좋은 BCJR기반 (2,1,7) 컨볼루션 부호를 적용하였으며, 다중 경로 전달로 인해 왜곡된 데이터를 보상하기 위해 결정 궤환 등화기가 결합된 터보 등화기 구조를 적용하였다. 문경시 경천호에서의 실제 수중 실험을 통하여 BCJR 기반의 터보 등화 구조가 다른 비터비 복호방식의 경판정, 연판정 기법에 비해 성능이 우수함을 검증하였다. 이러한 BCJR 복호의 성능은 반복횟수는 평균 1회에서 3회 정도에 오류가 정정되고, 복호기 입력단의 오류율이 10(-1)이하이면 모두 복호가 가능함을 볼 수 있으며, 16번의 수중통신 실험은 약 83%의 성공률을 획득하였다. Underwater acoustic communications has been limited use for military purposes in the past. However, the fields of underwater applications expend to detection, submarine and communication in recent. The excessive multipath encountered in underwater acoustic communication channel is creating inter symbol interference, which is limiting factor to achieve a high data rate and bit error rate performance. To improve the performance of a received signal in underwater communication, many researchers have been studied for channel coding scheme with excellent performance at low SNR. In this paper , we applied BCJR decoder based ( 2,1,7 ) convolution codes and to compensate for the distorted data induced by the multipath, we applying the turbo equalization method. Through the underwater experiment on the Gyeungcheun lake located in Mungyeng city, we confirmed that turbo equalization structure of BCJ R has better performance than hard decision and soft decision of Viterbi decoding. We also confirmed that the error rate of decoder input is less than error rate of 10(-1), all the data is decoded. We achieved sucess rate of 83% through the experiment.

소양호 (昭陽湖) 적조 수역 저질토에서의 미생물학적 물질 분해에 관하여

안태석 ( Tae Seok Ahn ) 한국하천호수학회 1990 생태와 환경 Vol.23 No.1

For elucidating the ecological functions of sediment and parts of carbon and phosphorus cycle, the degradation rates of organic phosphate, cellulose and cellobiose were estimated in the sediment of red tide area of Lake Soyang. The breakdown rates of cellulose ranged between 11.0∼99.0%/ month, and the major factor for breakdown was temperature. The range of cellobiose degradation rates was between 0.8∼4.7 %/hr, high in spring and low in summer. The organic phosphate degradation rates, showing the range of 16.4∼40.0%/hr, were high in winter, just after the Peridinium blooming and spring.