Among the different types of seaweed that are cultivated in Korea for food, Capsosiphon fulvescensis the filamentous green alga with the highest production value. However, its harvest yield varies significantly from year to year due to its dependence on the natural seeding method. The present study aimed to identify the conditions affecting the formation of cyst-zygotes that can be utilized as artificial seeds during the life cycle of C. fulvescens. Gametangia and zygotes of C. fulvescens were found to be highly developed at temperatures above 15°C, with a maximum gametangial development rate of about 35% observed after 7 days of culture. The formation of zygotes into cystzygotes was induced within 7 days in all temperature conditions, but after 30 days of culturing, cyst-zygotes germinated into filamentous thalli at temperatures above 20°C, while the most stable formation and stabilization were observed at 15°C. Cystzygotes formed at 15°C showed high growth when they were transferred to 25°C conditions, and zoospores matured inside the cells. The production of cyst-zygotes was mostly influenced by temperature, and a gradual increase in temperature was found to be necessary for the formation and growth of cyst-zygotes. The culture conditions facilitating the formation of cyst-zygotes reported in this study can be useful for the production of artificial seeds and breeding technology for the effective cultivation of seaweed.

Democratic People’s Republic of Korea (DPRK) has produced weapon-grade plutonium in a graphite-moderated experimental reactor at the Yongbyon nuclear facilities. The amount of plutonium produced can be estimated using the Graphite Isotope Ratio Method (GIRM), even without considering specific operational histories. However, the result depends to some degree on the operational cycle length. Moreover, an optimal cycle length can maximize the number of nuclear weapons made from the plutonium produced. For conservatism, it should be assumed that the target reactor was operated with an optimal cycle length. This study investigated the optimal cycle length using which the Calder Hall MAGNOX reactor can achieve the maximum annual production of nuclear weapons. The results show that lower enrichment fuel produced a greater number of critical plutonium spheres with a shorter optimal cycle length. Specifically, depleted uranium (0.69wt%) produced 5.561 critical plutonium spheres annually with optimal cycle lengths of 251 effective full power days. This research is crucial for understanding DPRK’s potential for nuclear weapon production and highlights the importance of reactor operational strategy in maximizing the production of weapons-grade plutonium in MAGNOX reactors.

Hand, foot, and mouth disease (HFMD) is a highly contagious disease with no specific treatment. Since it is common in immunocompromised children under the age of 5, there is a need to develop a safe vaccine. Virus-like particles (VLPs) are similar structures to viruses with the lack of genetic material which makes them impossible to replicate and infect, and therefore have a high level of biological safety and are considered to have high value as vaccines. In this study, the insect virus expression system that is widely used for vaccine and drug production due to its high post-translational modification efficiency, was used to produce VLPs for Coxsackievirus type A6 and A10, which are recently reported to be the main causes of HFMD. For this purpose, the selection of promoters that can control the timing and intensity of expression of 3CD protein, which is essential for VLPs assembly but has been reported to be cytotoxic, was conducted to construct an optimal expression form for HFMD-VLP.

본 연구에서는 국내산 돌미나리에서 GABA생성능이 있 는 신규 유산균을 분리, 동정한 결과, Enteroccoccus casseliflavus로 확인되었다. 최근까지 Lactobacillus속과 같 은 GABA 생성 유산균에 대한 보고는 많이 되고 있고, 일 부 Enterococcs속 유산균도 보고되고 있으나 E. casseliflavus 종에 대한 보고는 없었다. 따라서 본 연구에서는 E. casseliflavus PL05 균주에 대한 GABA 생성 최적 조건을 찾기 위하여 배지의 유형, 생육 온도, 초기 pH 조건, 배양 시간, MGS 농도 및 탄소원을 포함한 다양한 조건을 테스 트하였다. PL05 균주는 MRS 혹은 TSB 배지보다 BHI 배 지에서 생육이 잘 되었으며, 배지의 초기 pH는 7-9 조건 에서 가장 생육이 왕성하였고, GABA 생성 조건 역시 유 사한 결과로 확인되었다. GABA의 기질에 해당하는 MSG 의 농도별 GABA 생성량을 조사한 결과, 7%에서 가장 높 은 생성량을 나타내었으나 5%에서도 유사한 수준으로 확 인되어 효율적인 측면에서 5%가 적합할 것으로 판단된다. 탄소원에 따른 생육 및 GABA 생성량은 말토오스를 사용 하였을 때 가장 높은 것으로 확인되었고, 이러한 최적의 조건들로 최종 테스트를 진행한 결과, 24시간째 140.06±0.71 mM의 GABA가 생성되었고, 전환율은 78.95%로 확인되 었다. 또한 반코마이신을 포함한 10개의 항생제에 대한 감 수성을 조사한 결과 내성이 없는 것을 확인하였다.

This study studied a system that can redesign the production site layout and respond with dynamic simulation through fabric production process innovation for smart factory promotion and digital-oriented decision making of the production process. We propose to reflect the required throughput and throughput per unit facility of fabric production process as probability distribution, and to construct data-driven metabolism such as data collection, data conversion processing, data rake generation, production site monitoring and simulation utilization. In this study, we demonstrate digital-centric field decision smartization through architectural design for the smartization of fabric production plants and dynamic simulations that reflect it.

본 연구는 우리나라의 대표적인 난대 상록활엽수종 중의 하나인 가시나무의 고품질 용기묘 생산을 위한 적정 시비수준을 구명하고자 실시하였다. 용기는 임업시설양묘용 플라스틱 용기(350 ㎖/구)를 사용하였고, 시비처리는 무시비구와 함께 수용성 복합비료인 Multifeed 19 (N:P:K =19:19:19, v/v)를 1000 ㎎․L-1, 2000 ㎎․L-1, 3000 ㎎․L-1로 조절하여 시비하였다. 실험결과, 수고와 근원경 생장은 시비수준이 높아짐에 따라 높은 생장값으로 나타났다. 건물생산량도 전체적으로 수고 및 근원경 생장 결과와 유사한 경향으로 나타났다. 뿌리발달은 2000 ㎎․L-1 시비구에서 가장 왕성하였다. 묘목의 품질을 나타내는 지수인 QI (Quality Index)도 2000 ㎎․L-1 시비구에서 가장 높았다. 연구결과를 종합하면, 가시나무 용기묘의 우량한 묘목생산을 위한 적정 시비수준은 2000 ㎎․L-1 시비구로 판단된다.

본 연구는 대체에너지, 생태복원 및 밀원식물용 등으로 이용되어 묘목 수요가 증가되고 있는 쉬나무의 우량한 용기묘 생산을 위한 적정 시비수준을 구명하고자 실시하였다. 공시용기는 임업시설양묘용 플라스틱 용기(350 ㎖/구)를 사용하였다. 시비처리는 무시비구와 함께 수용성 복합비료인 Multifeed 19 (N:P:K=19:19:19, v/v)를 500 ㎎·L-1, 1000 ㎎·L-1, 1500 ㎎·L-1, 2000 ㎎·L-1로 조절하여 시비하였다. 실험결과, 간장과 근원경 생장은 시비수준이 높아짐에 따라 높은 생장값을 나타내다가 1000 ㎎·L-1 이상의 시비에서는 낮아지는 경향을 보였다. 뿌리발달은 1000 ㎎·L-1에서 가장 왕성하였다. 건물생산량도 1000 ㎎·L-1에서 가장 높았고 전체적으로 간장 및 근원경 생장 결과와 유사한 경향으로 나타났다. 묘목의 품질을 나타내는 지수인 QI (Quality Index)도 1000 ㎎·L-1에서 0.97로 다른 처리구 보다 높게 조사 되었다. 연구결과를 종합하면, 쉬나무 용기묘의 우량한 묘목생산을 위한 적정 시비수준은 1000 ㎎·L-1로 판단되며, 쉬나무 용기묘의 대량생산을 위한 기초자료로 활용될 것으로 기대된다.

본 연구는 최근 유용곤충으로 주목받고 있는 쌍별귀뚜라미의 생산 효율 증대를 위해 수행되었다. 이를 위해 부화율, 사육밀도에 따른 생존율, 산란온도에 따른 산란수을 조사하였다. 부화율은 상태습도 30%, 50%, 70% 및 90% 처리구에서 각각 42%, 66%, 82% 및 90%로 나타났다. 사육밀도는 150cm X 60cm X 50cm 용기에 3,000마리, 5,000마리, 10,000마리, 15,000마리, 20,000마리 처리구로 구분하여 수행하였으며, 30℃ 조건에서 부화한 유충이 성충까지 소요된 기간은 약 35일이었다. 생존율은 각각 34%, 31%, 28, 21% 및 18% 이었으며, 성충이 된 후 처리구별 생체 총 중량은 각각 858g, 1,257g, 2.778g, 3,091g 및 3,670g 으로 조사되었다. 산란수 조사는 20℃, 25℃ 및 30℃에서 30일간 조사하였으며, 평균 산란수는 각각 267개, 1,710개 및 1,042개이었다. 산란수 조사 30일 기간 중 10일간 평균 산란수는 각각 220개, 984개 및 647개로 82%, 57% 및 62%로 나타났다.

This experiment was conducted at Suwon, Korea from 2013 to 2015. The objective of this study was to establish the optimum seeding rate, and to clarify the nitrogen fertilizer level for rye seed production in central and north area of Korea. We used Korean rye cultivar ‘Gogu’ for this test. We employed a split-plot design with three replications. The main plots were designed by three seeding levels (3, 5 and 7 kg 10a-1), but other sub-plots were randomly seeded. The plots were treated with three different nitrogen fertilizer levels (3, 6 and 9 kg 10a-1). The percentage of productive tiller, number of grain per spike, fertility rate, 1 liter weight, and 1000-grain weight decreased as seeding rate increased from 3 kg 10a-1 to 7 kg 10a-1, whereas the number of spike per ㎡ increased. Therefore the grain yields of rye had less of an effect by increasing seeding rate. There was an increase in number of spike per ㎡, number of grain per spike, and fertility rate as nitrogen fertilizer level increased from 3 kg 10a-1 to 9 kg 10a-1, but grain yields significantly not affected by the interaction of seeding rate × nitrogen fertilizer levels. However, the best seeding rate and nitrogen fertilizer level for rye seed production were 5 kg and 5∼6 kg 10a-1, respectively, considering seed and fertilizer reduction and the prevention of pollution by excess fertilization.

Response Surface Methodology (RSM) is a widely used statistical analysis for finding an optimal point of a response variable (dependent variable) in accordance with multiple explanatory variables (independent variable). We have previously used RSM to identify optimal temperature and humidity (represented by the amount of water spray) of the fresh forage system for maximizing the growth of barley after 6 days of seeding. Consequently, RSM demonstrated that the optimal growth condition of barley was 19.70 and 1.38 l/h. However, it was not proved by empirical result, we aimed to verify the RSM result through comparative experiments. Experiments were designed four trials with different conditions. The first trial represented optimal conditions obtained from RSM, i.e., 20 and 1.4(l/h), while the rest of trials represented; 1) 20 and 1.8(l/h), 2) 18 and 1.4(l/h), and 3) 23 and 1.4(l/h). After 6 days of seeding, the average barley weight of the first trial was 11,094 g which was the highest yield compared to other trials (10,101 g, 9,757 g, and 10,233 g). This result supports that the RSM successfully predicted the optimal growth condition to be applied for the fresh forage system.

한국산 억새를 산, 알칼리 및 증기폭쇄법으로 전처리한 시료의 최적 효소당화조건을 탐색하고, 당화물을 이용한 에탄올 생산성을 구명하였다. 억새의 화학적 조성은 저분자화합물이 5.0%, lignin 17.0%, hemicellulose 55.1%, cellulose 22.7%이었다. 효소 당화율은 단용효소 처리구보다 혼용효소 처리구에서 높았다. Celluclast 처리구는 Viscozyme보다 높은 당화율을 보였으며, 가장 높은 당화율을 보인 효소 처리구는 EM-3(Celluclast 24.3FPU/g 기질+Viscozyme 80.6FBG/g 기질)로 약 70%의 당화율을 보였다. 산,알칼리 전처리를 통해 정제된 α-cellulose의 효소 당화율은 1% NaOH 처리 증기폭쇄재 보다 16% 높게 나타났다. 효소 cocktail의 당화에 가장 적합한 온도는 50℃였고, 모든 기질에서 효소 반응시간이 증가할수록 당화율이 증가하였다. 억새의 당화물은 오탄당으로 xylose가 육탄당으로 glucose가 주를 이루었다. S. cerevisiae KCCM 11215를 이용한 당화물의 에탄올 발효에서도 각 효소조합과 시료 전처리가 매우 중요한 것으로 나타났다. 억새시료 1kg 당 350g 이상의 에탄올 생산성을 보였으며, 1% NaOH 및 1% KOH를 처리한 증기폭쇄 시료보다 α-cellulose를 기질로 사용한 처리구에서 에탄올 생산성이 높았다.

This study aims to estimate optimal harvesting production, fishing efforts, and stock levels of yellow croaker caught by the offshore Stow Net and the offshore Gill Net fisheries using the current value Hamiltonian method and the surplus production model. As analyzing processes, firstly, this study uses the Gavaris general linear model to estimate standardized fishing efforts of yellow croaker caught by the above multiple fisheries. Secondly, this study applies the Clarke·Yoshimoto·Pooley(CY&P) model among the various exponential growth models to estimate intrinsic growth rate(r), environmental carrying capacity(K), and catchability coefficient(q) of yellow croaker which inhabits in offshore area of Korea. Thirdly, the study determines optimal harvesting production, fishing efforts, and stock levels of yellow croaker using the current value Hamiltonian method which is including average landing price of yellow croaker, average unit cost of fishing efforts, and social discount rate based on standard of the Korean Development Institute. Finally, this study tries sensitivity analysis to understand changes in optimal harvesting production, fishing efforts, and stock levels of yellow croaker caused by changes in economic and biological parameters. As results drawn by the current value Hamiltonian model, the optimal harvesting production, fishing efforts, and stock levels of yellow croaker caught by the multiple fisheries were estimated as 19,173 ton, 101,644 horse power, and 146,144 ton respectively. In addition, as results of sensitivity analysis, firstly, if the social discount rate and the average landing price of yellow croaker continuously increase, the optimal harvesting production of yellow croaker increases at decreasing rate and then finally slightly decreases due to decreases in stock levels of yellow croaker. Secondly, if the average unit cost of fishing efforts continuously increases, the optimal fishing efforts of the multiple fisheries decreases, but the optimal stock level of yellow croaker increases. The optimal harvest starts climbing and then continuously decreases due to increases in the average unit cost. Thirdly, when the intrinsic growth rate of yellow croaker increases, the optimal harvest, fishing efforts, and stock level all continuously increase. In conclusion, this study suggests that the optimal harvesting production and fishing efforts were much less than actual harvesting production(35,279 ton) and estimated standardized fishing efforts(175,512 horse power) in 2013. This result implies that yellow croaker has been overfished due to excessive fishing efforts. Efficient management and conservative policy on stock of yellow croaker need to be urgently implemented.

This study aimed to examine the applicability of a portfolio approach to the ecosystem-based fisheries management targeting the large purse seine fishery. Most fisheries are targeting multispecies and species are biologically and technically interacted each other. It enables a portfolio approach to be applied to find optimal production of each species through expected returns and risk analyses. Under specific assumptions on the harvest quota by species, efficient risk-return frontiers were generated and they showed a combination of optimal production level. Comparisons between portfolio and actual production provided a useful information for targeting strategy and management. Results also showed the possibility of effective multispecies fisheries management by imposing constraints on each species such as total allowable catch quotas.

As a specialty oil, furan fatty acids have gained special attentions since they are known to play important roles in biological systems including human. Although several studies reported chemical synthesis of furan fatty acids, their synthesis consisted of complicated chemical multistep with chemical catalysts. Recently, a simple one-step heat treatment method was developed to produce a novel furan fatty acid, 7,10-epoxy-octadeca-7,9-dienoic acid (7,10-EODA) from a dihydroxyl fatty acid 7,10-dihydroxy-8(E)-octadecenoic acid (DOD). In this report we studied about optimization of environmental conditions for the maximum production of 7,10-EODA from DOD by heat treatment. Production of 7,10-EODA was maximized at over 85℃ for at least over 48 hour in hexane. Solvent volume for maximum production should be over 300 mL per 10 mg DOD.

The purpose of this study was to investigate the antioxidative effects of Opuntia humifusa and determine the optimal mixing ratio of Opuntia humifusa powder and eggs for the preparation of pasta. In regard to its antioxidant effects, Opuntia humifusa powder had a total phenolic content and DPPH free radical scavenging activity of 6.64 mg/g and 90.12%, respectively. We used response surface methodology to obtain ten experimental points (including two replicates for Opuntia humifusa powder and egg) and Opuntia humifusa pasta formulation was optimized using rheology. Yellowness (p<0.001) displayed a linear model pattern, whereas lightness (p<0.01) and redness (p<0.01) were described by a quadratic model pattern. Mechanical properties showed significant values in hardness (p<0.5), chewiness (p<0.5), gummiess (p<0.5), and cohesiveness (p<0.5). The sensory evaluation parameters showed significant differences in color (p<0.5), appearance (p<0.5), flavor (p<0.5), texture (p<0.5) and overall quality (p<0.5). The optimum formulations processed by numerical and graphical optimization were found to be 7.30 g of Opuntia humifusa powder and 31.55 g of egg.

The demand for facility used in producing multi-products is changed dynamically for discrete and finite time periods. The excess or the shortage for facility is occurred according to difference of the facility capacity size and demand for facility through given time periods. The shortage facility is met through the outsourcing production. The excess facility cost is considered for the periods that the facility capacity is greater than the demand for the facility, and the outsourcing production cost is considered for the periods that the demand for facility is greater than the facility capacity. This paper addresses to determine the facility capacity size, outsourcing production products and amount that minimizes the sum of the facility capacity cost, the excess facility cost and the outsourcing production cost. The characteristics of the optimal solution are analyzed, and an algorithm applying them is developed. A numerical example is shown to explain the problem.