클린룸의 청정도와 최적 환기 횟수에 대한 고찰

장창익 대한설비공학회 2008 설비저널 Vol.37 No.8

唐 高宗 시기 2次 高句麗 遠征과 政局의 再編

장창익 동양사학회 2021 동양사학회 학술대회 발표논문집 Vol.2021 No.4

[CEO COLUMN] “새로운 길 위에서, 세 가지 다짐”

장창익 대한전기협회 2019 전기저널 Vol.- No.505

한국 근해 참조기의 자원평가 및 관리방안

장창익,김수암,윤성봉 한국수산학회 1992 한국수산과학회지 Vol.25 No.4

한국근해 참조기의 지난 20여년 동안의 어획자료를 사용하여 잉여생산량 모델에 의해 추정된 MSY를 비교하여 보면, Shaefer와 Fox 모델에 의하여 추정된 값들은 각각 37,000mt와 33,450mt였고, Zhang 모델에 의하여 자원량과 순간어획사망계수를 적용시킨 MSY는 45,328mt, 자원량과 어획량 자료를 이용하는 방법에서는 40,160mt로 각각 추정되었다 이 현상은 이 모델들이 각기 독립된 다른 자료를 이용하여 MSY를 추정하였으나, 추정된 값은 거의 비슷한 결과를 보였다. 참조기자원을 가입당생산량 모델에 적용시킨 결과를 사용하여 자원관리 방안을 모색해 보면, 가능한 최대 가입당 생산량이 43g임에 비하여 현재의 t_c=0.604, F=1.11에서의 가입당생산량은 약 20g 정도에 불과하다. 여기서 t_c를 현재 상태로 고정시킨후, 가입당생산량을 높이는 방안을 생각해 보면, F를 현재의 1.11에서 0.4 정도로 낮추어야 하나, 가입당생산량의 큰 증가는 없다. 즉, 현재의 20g에서 25g밖에 증가되지 않는다. 그러나, 현재의 어획강도 (F)를 고정시키는 경우에는 t_c를 현재의 0.604세에서 3세 부근으로 조정하면 최대의 가입당생산량 (43g)을 얻을 수 있고, 이 t_c 값은 역시 F_(0.1) 방법에서 추정된 적정어획체장을 연령으로 환산한 결과와 거의 일치함을 알 수 있다. Zhang모델을 이용한 자원의 회복 방안에서 참조기 자원의 최대생산가능 자원량(B^*_MSY)를 유지시키려면 F를 약 0.5 수준으로 낮추어야 하고. 이 수준에서 약 8년 뒤에는 자원량이 적정 수준에 거의 접근하게 된다. Based on surplus production models using fishery data for the last 20 years, a stock assessment was conducted for the small yellow croaker in Korean waters. The maximum sustainable yields (MSY) from the Schaefer and Fox models were estimated to be 37,000 metric tons (mt) and 33,450 mt. Zhang's model using time-series biomass with instantaneous coefficients of fishing mortality (F) and using time-series biomass and catch yielded MSY estimates of 45,328 mt and 40,160 mt, respectively. A yield-per-recruit analysis showed that the current yield per recruit of about 20g with F=1.11 yr^(-1), where the age at first capture (t_c) is 0.604, was much lower than the maximum possible yield per recruit of 43g. Fixing t_c at the current level and reducing fishing intensity (F) from 1.11 yr^(-1) to 0.4 yr^(-1) yielded only a small increase in predicted yield per recruit, from 20 to 25g. However, estimated yield per recruit increased to 43g by increasing t_c from the current age (0.604) to age three with F fixed at the current level. This age at first capture corresponded to the optimal length which was obtained from the F_(0.1) method. According to the analysis of stock recovery strategies employing the Zhang model, the optimum equilibrium biomass (B^*_MSY) which produces the maximum yield could be achieved after approximately five years at the lower fishing intensity (F=0.5).

Estimation of mortality coefficients and survivorship curves for minke whales (Balaenoptera acutorostrata) in Korean waters

장창익,나종훈,송경준 한국통합생물학회 2010 Animal cells and systems Vol.14 No.4

Population ecological characteristics of growth and mortality play an important role in understanding the population dynamics of marine mammals. The instantaneous coefficients of natural and bycatch mortality were estimated for minke whales (Balaenoptera acutorostrata) in Korean waters using a population assessment model composed of bycatch and abundance data. The survivorship curve of this population was fitted to the data, and then the curve was revised using age-specific relative bycatchability coefficients (qt). Instantaneous coefficients of natural and bycatch mortality of minke whales were estimated as 0.024/year and 0.076/year, respectively, and from this the survival rate was estimated as 0.905. This estimated survival rate was comparable to other cetaceans in other regions. The qt for this population ranged from 0.020 to 0.193. The revised survival rates were higher when the qt was taken into account. The mortality coefficient, survival rate, qt and survivorship curves had not previously been determined for minke whale in this area. This estimate could serve as fundamental information to assess the status of this population and for conservation and rational management.

시계열 분석에 의한 어획량 예측 : 한국 근해산 갈치를 예로 하여

장창익,유신재 한국수산학회 1993 한국수산과학회지 Vol.26 No.4

어획량의 단기 예측은 자원관리에 있어 중요한 항목이지만 전통적인 개체군 모델은 수산자원 관리에 있어 실제적으로 요구되는 예측력이 크게 부족하다. 다종 또는 생태계 모델도 요구되는 매개변수의 수가 많아 실제적 적용이 어렵다. 반면에 단변수 시계열 분석법은 시계열 자체에서 변동성에 관한 특성을 추정하여 이를 토대로 장래 변동성을 예측함으로 최소한의 자료를 가지고 비교적 정확한 단기예측이 가능하므로 유용성이 높다. 본 연구에서는 ARIMA 시계열 모델을 1971∼1988년 간의 한국근해의 월별 갈치어획량 자료에 적용하였다. 여기서 나온 예측치와 분석에 포함되지 않았던 1989∼1990년 간의 어획량과 비교하였다. 분석 결과 예측치와 실제어획량이 잘 일치하였으며(r=0.938) 평균상대오차는 59.5%였다. Short-term forecasting of fish catch is of practical importance in fisheries management. Ecosystem models and multi-species models as well as traditional single-species models fall short of predicting power needed for practical management of fisheries resources due to the lack of sufficient data or information for the required parameters. Univariate time series analysis, on the other hand, extracts the information on the stochastic variability from the time series itself and makes estimates of the future stochastic variability. Therefore, it can be used for short-term forecasting with minimum data requirements. ARIMA time series modeling has been applied to the monthly Korean catches of hairtail (Trichiurus lepturus) for 1971∼1988. Forecasts of hairtail catch were made and compared with the actual catch data from 1989∼1990 which were not included in the parameter estimation. The results showed a good agreement (r=0.938) between the forecasts and the actual catches with a mean relative error of 59.5%.

바다목장의 생태계 기반 자원관리방안

장창익,이성일,김종만 한국수산자원학회 2003 한국수산자원학회지 Vol.6 No.-

An ecosystem-based approach is introduced to manage fisheries resources in marine ranching areas by considering ecological interactions of organisms in the ecosystem. The ecosystem structure model (ESM) analyses ecotrophic levels among functional groups in the ecosystem and the ecosystem dynamic model (EDM) conducts dynamic simulation of the ecosystem according to the fishing mortality intensity or environmental changes. Here, we developed two models : the fishery stock enhancement model which estimates parameters to enhance required fishery stocks by artificial releasing and the ABC(acceptable biological catch) estimation model for an effective fishery resource management. In addition, methods for estimating parameters required for the ecosystem models and population models were also investigated. Finally, a necessity for studying the ecosystem-based approach for the management of fisheries resources was stressed.

동부베링해산 알라스카 가자미의 식성과 타 가자미류와의 생태학적 상호작용

장창익 한국수산학회 1988 한국수산과학회지 Vol.21 No.3

Food habits of Alaska plaice, Pleuronectes quadrituberculatus, and ecological interactions of this species with yellowfin sole, Limanda aspera, and rock sole, Lepidopsetta bilineata, in the eastern Bering Sea were studied. Alaska plaice mainly feed on polychaetes regardless of sex and size of fish. However, it was shown that food differed by sampling area. Feeding did not occur at night. Food competition seems to be negligible among the three shallow water flatfish species inhabiting the eastern Bering Sea due to differences in food spectra or spatial distribution.

남서부 동해에서 1970년대의 기후체제전환이 생태계의 구조에 미친 영향

장창익,윤상철 한국수산과학회 2003 한국수산과학회지 Vol.36 No.4

The changes in structure and abundance of taxon or species groups in the East Sea ecosystem were compared between pre- and post-Climatic Regime Shift (CRS) occurred in the mid 1970s using an ECOPATH model. Although the East Sea ecosystem consisted of primary producers, primary consumers, secondary consumers and terminal consumers most species groups were classified as secondary consumers. The mean trophic level between pre- and post-CRS increased from 3.09 during the pre-CRS period to 3.28 during the post-CRS period. Total biomass of the species groups in the East Sea ecosystem increased by 9% due to the CRS, and total catch increased by $48\%.$ The most significant differences between pre- and post-CRS models occurred at the mid/high trophic levels occupied by fishes and cephalopods. Relative contribution of the different species groups to the total energy flow was calculated for the trophic level III. As a result, the status by the dominant species in the East Sea ecosystem shifted from cephalopods to walleye pollock due to the CRS. Relative contribution of 5 species, which were commercially important, such as Pacific saury, Pacific sardine, filefish, walleye pollock and sandfish in trophic level III, were also changed due to the CRS. Finally, the CRS turned out to cause large variations in biomass and catch of fisheries resources as well as the status and role of the major species.

어항과 수산생물 - 투과성구조등서식장구실도

장창익 한국어촌어항협회 1990 어항어장 Vol.11 No.-