• 대한의용생체공학회:학술대회논문집
• /
• 대한의용생체공학회 1998년도 추계학술대회
• /
• pp.78-79
• /
• 1998

This paper describes a real time algorithm for blood flow estimation of LDF(laser Doppler flowmeter). Many algorithms for blood flow estimation are using power spectral density of Doppler signal by blood flow. In these research, the fast Fourier transformation is used to estimate power spectral density. This is a block processing procedure rather than real time processing. The algorithm in this paper used parametric spectral estimation. This has real time capability by estimation of AR(autoregressive) parameters sample by sample, and has smoothing power spectrum. Also, the frequency resolution is not limited by number of samples used to estimate AR parameter. Another advantage of this algorithm is that AR model enhance SNR.

• 대한의용생체공학회:의공학회지
• /
• 제19권2호
• /
• pp.153-162
• /
• 1998

인공 심장의 연구에 있어서 혈류 역학 변수의 추정은 두말할 필요도 없이 매우 중요하다. 그러나 이 중요도에 견주어 볼지라도 실세계에 적용될 수 있는 연구 결과는 희박하다. 본 논문에서는 이동 작동기형 완전 인공 심장을 위한 혈류 역학 변수 추정 문제가 연구되었다. 추정 방법론으로서 다차원 선형 보간 기법을 이용하였다. 모의 순환 장치의 실험으로 제안된 방법을 검증하였으며 좋은 성능을 보였다.

• 대한의용생체공학회:학술대회논문집
• /
• 대한의용생체공학회 1998년도 추계학술대회
• /
• pp.195-196
• /
• 1998

Nonlinear energy operator(NEO) is usually used to estimate energy content of linear oscillator. We applied the modified nonlinear energy operator (MNEO) to detect R-peak of ECG and analyzed variation of R-R interval during sleep with nonlinear methods, piecewise correlation dimension and approximate entropy (ApEn) which estimate complexity of time series. ApEn applied to R-R interval reveals trends as sleep state changes.

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제2권2호
• /
• pp.69-72
• /
• 1997

The pH of microbial culture medium was calculated from equations of equilibrium, meterial balances for ionic components and electro-neutrality theory. Ammonium ion consumption and Acetic acid production are found out to be the major contributors for the alteration of the pH as well as the buffer capacity of the medium. By measuring the buffer capacity on-line, levels of acetic acid were estimated by a software sensor using pH signal in a fermentation process of E.coli growing in a minimal medium. The measured values of acetic acid showed good correlation to those of estimated by the software sensor.

• KSBB Journal
• /
• 제13권4호
• /
• pp.461-467
• /
• 1998

A fermentation system was supplemented with a device for the measurement of the durations of alkali pump feeding for automatic pH control and an A/D convertor for precise monitoring of pH value by computer. A software program was developed to measure buffer capacities from the pH signal and the pH control signal during fermentation. By measuring the buffer capacity on-line, levels of acetic acid were estimated by a software sensor using pH signal in a fermentation process of E.coli growing in a minimal medium. The measured values of acetic acid showed correlation to those of estimated by the software sensor. Lacitic acid production was also successfully estimated by the values of buffer capacities measured on-line.

• 제어로봇시스템학회논문지
• /
• 제14권11호
• /
• pp.1174-1179
• /
• 2008

Many modeling and calibration methods have been developed to analyze and design the biological wastewater treatment process. For the systematic use of activated sludge model (ASM) in a real treatment process, a most important step in this usage is a calibration which can find a key parameter set of ASM, which depends on the microorganism communities and the process conditions of the plants. In this paper, a standardized calibration protocol of the ASM model is developed. First, a weighted effluent quality index(WEQI) is suggested far a calibration protocol. Second, the most sensitive parameter set is determined by a sensitive analysis based on WEQI and then a parameter optimization method are used for a systematic calibration of key parameters. The proposed method is applied to a calibration problems of the single carbon removal process. The results of the sensitivity analysis and parameter estimation based on a WEQI shows a quite reasonable parameter set and precisely estimated parameters, which can improve the quality and the efficiency of the modeling and the prediction of ASM model. Moreover, it can be used for a calibration scheme of other biological processes, such as sequence batch reactor, anaerobic digestion process with a dedicated methodology.

• 한국환경보건학회지
• /
• 제28권2호
• /
• pp.149-160
• /
• 2002

Analysis of benthic macroinvertebrate community structure and biological estimation of water quality by the benthic macroinvertebrates from the Mt. Myungji(1267m), Mt. Kalbong(840m), Mt. Daegeum(704m) and Mt. Jubal(489m) region of Gapyung-gun, Kyunggi-do were investigated from April to November, 2001. Total taxa of benthic macroinvertebrates were 105 species, 38 families, 13 orders, 5 classes in 4 phyla. Aquatic insects were 33 species in ephemeroptera, 5 species in odonata, 13 species in plecoptera, 2 species in hemiptera, 1 species in megaloptera, 27 species in trichoptera, 3 species in coleoptera and 13 species in diptera, respectively. Non-insects were 1 species in platyhelminthes, 5 species in gastropoda, 1 species in oligochaeta, 1 species in crustacea, respectively. Ephemeroptera, trichoptera and plecoptera as indicators in clean water were very abundantly. Occurrence species at each survey area was 67 species at Mt. Myungji and 69 species at Mt. Kalbong, 48 species at Mt. Daege.um and 47 species at Mt. Jubal, respectively. Mean species diversity indices at Mt. Myungji, Mt. Kalbong, Mt. Daegeum and Mt. Jubal were 3.30, 3.33, 2.59 and 3.43, respectively. According to the saprobic system based on the species diversity indices of benthic macroinvertebrates, Mt. Myungji, Mt. Kalbong and Mt. Jubal are determined as Limnosaprobic area, respectively, but Mt. Daegeum is determined as $\beta$-mesosaprobic area.

• ALGAE
• /
• 제23권4호
• /
• pp.289-294
• /
• 2008

To estimate seaweed biomass or standing crop, a nondestructive sampling can be beneficial because of not much destroying living plants and saving time in field works. We suggest a methodological procedure to estimate seaweed biomass per unit area in marine benthic habitats by using species-specific regression equations. Percent cover data are required from the field samplings for most species to convert them to weight data. However, for tall macroalgae such as kelps we need density data and their size (e.g., size class for subtidal kelps) of individuals. We propose that the field sampling should be done with 5 replicates of 50 cm x 50 cm quadrat at three zones of intertidals (upper, middle, lower) and three depth points (1, 5, 10 m) in subtidals. To obtain a reliable regression equation for a species, a substantial number of replicate is necessary from destructive samplings. The regression equation of a species can be further specified by different locality and different season, especially for the species with variable morphology temporally and spatially. Example estimation carried out in Onpyung, Jeju Island, Korea is provided to compare estimated values with real weight data.

• Journal of Welding and Joining
• /
• 제11권2호
• /
• pp.27-41
• /
• 1993

The estimation of nugget sizes was attempted by utilizing the artificial neural networks method. Artificial neural networks is a highly simplified model of the biological nervous system. Artificial neural networks is composed of a large number of elemental processors connected like biological neurons. Although the elemental processors have only simple computation functions, because they are connected massively, they can describe any complex functional relationship between an input-output pair in an autonomous manner. The electrode head movement signal, which is a good indicator of corresponding nugget size was determined by measuring the each test specimen. The sampled electrode movement data and the corresponding nugget sizes were fed into the artificial neural networks as input-output pairs to train the networks. In the training phase for the networks, the artificial neural networks constructs a fuctional relationship between the input-output pairs autonomusly by adjusting the set of weights. In the production(estimation) phase when new inputs are sampled and presented, the artificial neural networks produces appropriate outputs(the estimates of the nugget size) based upon the transfer characteristics learned during the training mode. Experimental verification of the proposed estimation method using artificial neural networks was done by actual destructive testing of welds. The predicted result by the artifficial neural networks were found to be in a good agreement with the actual nugget size. The results are quite promising in that the real-time estimation of the invisible nugget size can be achieved by analyzing the process variable without any conventional destructive testing of welds.

• 한국산림과학회지
• /
• 제96권4호
• /
• pp.483-493
• /
• 2007

본 연구는 조건부가치평가법을 사용하여 순천 희어리 군락지의 생물다양성 보전가치를 추정하는데 목적이 있다. 지불의사유도 방법에 따라 3가지 다른 모형별로 순천 희어리 군락지의 생물다양성 보전가치를 추정하여 제시하였다. 추정된 금액의 평균값을 계산하여 보면, 멸종위기 희귀식물종 서식지역(순천시 서면 히어리 군락지)의 생물다양성 보전에 따른 순천지역 주민의 가구당 월 평균지불의사금액은 약 3,380원, 연간 총 가치는 약 33억원으로 추정되었다. 이러한 추정결과는 순천시 서면 히어리 군락지에 생물다양성 보전프로그램이 실시될 경우, 지역주민의 생계활동(농사, 임업 등)과 관련된 편익, 생태관광 및 산책과 같은 여가활동으로 인한 편익, 후손 및 미래이용을 위한 편익, 그리고 멸종위기 희귀동식물 서식지역 보호로 인한 편익 등의 가치가 약 33억원 발생한다는 것을 시사하고 있다.