• Journal of Biosystems Engineering
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• v.40 no.2
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• pp.137-144
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• 2015

Purpose: The high energy requirement of extraction of oil from jatropha seed and reduction of loss in oil content between whole seed and kernel of jatropha necessitate seed shelling. The purpose of this study is to develop and evaluate the performance of a jatropha seed shelling machine based on seed moisture content. Methods: A shelling machine was designed and constructed for jatropha seed. The components are frame, hopper, shelling chamber, concave, and blower with discharge units. The performance evaluation of the machine was carried out by determining parameters such as percentage of whole kernel recovered, percentage of broken kernel recovered, percentage of partially shelled seed, percentage of unshelled seed, machine capacity, machine efficiency, and shelling efficiency. All of the parameters were evaluated at five different moisture levels: 8.00%, 9.37%, 10.77%, 12.21%, and 13.68% w.b.). Results: The shelling efficiency of the machine increased with increase in seed moisture content; the percentage of whole kernel recovered and percentage of partially shelled seed decreased with increase in moisture content; and percentage of broken kernel, machine efficiency, and percentage of unshelled seed followed a sinusoidal trend with moisture content variation. Conclusion: The best operating condition for the shelling machine was at a moisture content of 8.00% w.b., at which the maximum percentage of whole kernel recovered was 23.23% at a shelling efficiency of 73.95%.

• Korean Journal of Organic Agriculture
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• v.22 no.1
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• pp.1-23
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• 2014

The purpose of this paper was to measure technical efficiencies and scale efficiencies of Korean seed industry by DEA method, and to identify the factors affecting the efficiencies by Tobit regression model. Survey data of 50 seed companies nationwide were applied for the analysis. The average score of overall technical efficiency for the surveyed companies in 2012 was 0.44, which is decomposed into pure technical efficiency 0.68 and scale efficiency 0.63. A majority of the seed companies exhibited at least one form of inefficiency except a few companies in optimal scale. It was also shown the most companies were operating in the stage of increasing returns to scale, which implies Korean seed companies are mainly in smaller scale than optimal. Additional results suggest that the Center for Private Seed Companies, which will be established at Gimje in 2015, plays an important role to make domestic seed companies improve their scale efficiency as well as pure technical efficiency by way of enlarging their size and co-using the high technology in the Center.

• Journal of Biosystems Engineering
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• v.41 no.3
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• pp.193-200
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• 2016

Purpose: New low-cost oilseeds are needed to meet an ever-increasing demand for oil for food, pharmaceutical, and industrial applications. African oil bean seed is a tropical crop that is underutilized and has high oil yields, but there have been no studies conducted on its mechanical oil expression up to now. The objective of this work was to investigate the effect of moisture content and seed dimensions on mechanical oil expression from the seeds. Methods: Fresh oil bean seeds were procured, de-hulled, and cleaned. Initial seed moisture content, obtained in accordance with the ASAE standard, was 12% dry basis (db). The seeds were further conditioned by dehydration and rehydration prior to oil expression to obtain four other moisture levels of 8, 10, 14, and 16% db. The major diameter of the seeds was measured using digital vernier calipers, and the seeds were classified into size dimensions (< 40, 41-45, 46-50, 51-55, and > 55 mm). The oil yield and expression efficiency were obtained in accordance with standard evaluation methods. Results: The highest oil yield and expression efficiency (47.74% and 78.96%, respectively) were obtained for a moisture content of 8% db and seed dimensions of < 40 mm, while the lowest oil yield and expression efficiency (41.35% and 68.28%, respectively) were obtained for a moisture content of 14% db and seed dimensions between 51-55 mm. A mathematical model was developed to predict oil yield for known moisture content and seed dimensions, with a coefficient of determination $R^2$ of 95% and the confidence level of the predictive model of 84.17%. The probability of prediction F ratio showed that moisture content influence was more significant than seed dimensions. Conclusions: The higher the moisture content and larger the seed dimensions, the lower the oil yield from African oil bean seeds.

• The Journal of Fisheries Business Administration
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• v.51 no.1
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• pp.37-52
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• 2020

The production of abalone seed has grown and been specialized since the 2000s with the growth of the abalone farming industry. Despite the increase in the production of abalone seeds, the sales volume of abalone seeds remained flat and competition among producers increased. This paper will analyze the management efficiency of abalone seed production fishery to diagnose the management status and improve the abalone seed production efficiency. In addition, this study is the result of the basic research on the abalone seed industry and it is meaningful to prepare a platform for further research since the management status survey and the management efficiency survey of abalone seed production fishery have not been conducted until now. The data on the farmed fish prices of abalone seeds were collected from surveys of sample fish as part of the fish seed observation project conducted by the Fisheries Outlook Center (FOC) of Korea Maritime and Fisheries Development Institute (KMI). Management efficiency analysis utilizes DEA (Data Envelopment Analysis) model. The DEA model was analyzed by classifying into CCR (Super-CCR), BCC, and SBM (Super-SBM) models according to the assumptions taking into account the characteristics of the industry. The slack considered in the SBM model was judged as possible decreases in input variables and increase in output variables. The average efficiency from the CCR model was analyzed to be 69%. The BCC model was classified into input and output orientations, and the average efficiency was 79% and 75%, respectively. There were seven production fisheries with an SE value of 1 or more, which remained unchanged in terms of size and could be benchmarked. The average efficiency of the SBM model was 59% for CRS and 66% for VRS. Under the VRS assumptions, the variable increase/decrease efficiency analysis shows that labor costs can be reduced by 37.3%, facility capacity by 18.8%, and operating costs by 8.5%. In order to improve management efficiency, Wando needs to reduce labor and management costs. In Jindo region, sales increase as well as labor cost reduction is urgent. In other regions, reduced facilities and increased sales are recommended.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.3
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• pp.357-365
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• 2019

Objective: The experiment was conducted to evaluate the effects of four fungal pretreatments on the nutritional value of Camellia seed residues, and to evaluate the feeding value of pretreated Camellia seed residues for ruminants. Methods: Camellia seed residues were firstly fermented by four lignin degrading fungi, namely, Phanerochaete chrysosporium (P. chrysosporium)-30942, Trichoderma koningiopsis (T. koningiopsis)-2660, Trichoderma aspellum (T. aspellum)-2527, or T. aspellum-2627, under solid-state fermentation (SSF) conditions at six different incubation times. The nutritional value of each fermented Camellia seed residues was then analyzed. The fermentation profiles, organic matter degradability and metabolizable energy of each pre-treated Camellia seed residue were further evaluated using an in vitro rumen fermentation system. Results: After 5 days of fermentation, P. chrysosporium-30942 had higher degradation of lignin (20.51%), consumed less hemicellulose (4.02%), and the SSF efficiency reached 83.43%. T. koningiopsis-2660 degraded more lignin (21.54%) and consumed less cellulose (20.94%) and hemicellulose (2.51%), the SSF efficiency reached 127.93%. The maximum SSF efficiency was 58.18% for T. aspellum-2527 and 47.61% for T. aspellum-2627, appeared at 30 and 15 days respectively. All the fungal pretreatments significantly improved the crude protein content (p<0.05). The Camellia seed residues pretreated for 5 days were found to possess significantly increased organic matter degradability, volatile fatty acid production and metabolizable energy (p<0.05) after the treatment of either P. chrysosporium-30942, T. koningiopsis-2660 or T. aspellum-2527. The fungal pretreatments did not significantly change the rumen fermentation pattern of Camellia seed residues, with an unchanged ratio of acetate to propionate. Conclusion: The fungi showed excellent potential for the solid-state bioconversion of Camellia seed residues into digestible ruminant energy feed, and their shorter lignin degradation characteristics could reduce loss of the other available carbohydrates during SSF.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.32 no.2
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• pp.417-437
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• 2022

The quality of the fuzzing seed file is one of the important factors to discover vulnerabilities faster. Although the prior seed generation paradigm, using dynamic taint analysis and symbolic execution techniques, enhanced fuzzing efficiency, the yare not extensively applied owing to their high complexity and need for expertise. This study proposed the DDRFuzz system, which creates seed files based on sequence-to-sequence models. We evaluated DDRFuzz on five open-source applications that used multimedia input files. Following experimental results, DDRFuzz showed the best performance compared with the state-of-the-art studies in terms of fuzzing efficiency.

• Journal of Advanced Marine Engineering and Technology
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• v.16 no.5
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• pp.97-110
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• 1992

Rape-seed oil has high viscosity and high rubber content like other vegetable oils. When crude rape-seed oil obtained by a general oil extraction process is used in a diesel engine, automization condition during injection is not good and a large amount of combustion product is doposited in a combustion chamber. The improvement of a diesel engine is required to use rape-seed oil as a diesel engine fuel. In this study, the physical and chemical properties and combustion characteristics of rape-seed oil were investigated. The auxiliary aid was developed to improve automization condition and the effect of the auxiliary injection aid on the performance of a diesel engine was determined. The results are as follows. 1) Oil content of rape-seed is 45%. The exraction rate is 33%. The resuls show higher values compared to those of other vegetable oils. 2) The viscosity of rape-seed oil is 50.8 cSt and nearly 14 times of diesel oil viscosity. 3) The heating value and flash point of rape-seed oil are 9720kcal/Kg and 318$^{\circ}C$, respectively. 4) In case rape-seed oil is used as fuel, brake horse power, specific fuel consumption and brake thermal efficiency are compared to those of diesel oil. The results of rape-seed oil show 3.6%, 12.7% and 3.1% higher values. 5) Particle size of injection fuel with the auxiliary injection aid on the performance of a diesel engine was determined. The results are as follows. 1) Oil content of rape-seed is 45%. The extraction rate is 33%. The results show higher values compared to those of other vegetable oils. 2) The viscosity of rape-seed oil is 50.8 cSt and nearly 14 times of diesel oil viscosity. 3) The heating value and flash point of rape-seed oil are 9720kcal/Kg and 318.deg.C, respectively. 4) In case rape-seed oil is used as fuel, brake horse power, specific fuel consumption and brake thermal efficiency are compared to theose of diesel oil. The results of rape-seed oil show 3.6%, 12.7% and 3.1% higher values. 5) Particle size of injection fuel with the auxiliary injection aids is 100.mu.m smaller than that od injection fuel without the aid. 6) Brake horse power and brake thermal efficiency with the auxiliary injection aid increase 5.07% and 6.07%, respectively. However, specific fuel consumption decreases 3.85% with the auxiliary injection aid.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.3
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• pp.279-283
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• 2011

The immature embryos during seed development were examined to predict the suitable embryos for an efficient regeneration system. Five spring wheat genotypes and five winter wheat genotypes were tested using immature embryos as explants. Spring wheat genotypes showed much higher levels of plant regeneration than those of winter wheat genotypes. The highest frequencies of embryogenesis and regeneration were obtained when embryos at 13-14 days after anthesis (DAA) were used as explant and decreased using embryos at 21-22 DAA during seed development. Significant differences were also found for callus induction and regeneration as affected by immature embryo size. The regeneration efficiency was drastically decreased in spring and winter wheat genotypes when embryos larger than 2.0 mm of length were used. The optimum developmental stage and embryo length for regeneration efficiency were at 13-14 DAA and 1.0-1.5 mm, respectively. The selection of suitable embryos for the high frequencies of embryogenesis and regeneration leads us to efficient genetic improvement of wheat.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.2
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• pp.207-212
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• 2008

This study focused on shorten the period of the struvite crystal birth and development by adding seed materials. For this purpose, three different seed materials were selected: sand, anthracite and struvite. The experiments has been conducted to evaluate the effect of the particle size of the selected seed material on the struvite crystallization, and to study the mixing effect which can be expressed by the value of $G{\cdot}t_d$(the multiple of mean velocity gradient(G) and mixing time($t_d$)). It was observed in this study that the removal efficiency of ammonia nitrogen increased by 9%, 11%, and 20% for sand, anthracite, and struvite added as the seed material, respectivley. This indicated that the struvite crystallization efficiency had a close correlation with the specific surface area of the seed particle. It was found that when struvite was selected as the seed material, the struvite crystallization proceeded at lower $G{\cdot}t_d$ value as compared with other seed materials. This observation implied that the secondary crystal birth would be dominated in this reaction. It was concluded in this study that the particle size was not significant factor on the struvite crystallization, while the $G{\cdot}t_d$ value was a considerably important factor in terms of the theory of the struvite crystal birth.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.330-338
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• 1999

Extensive research has been conducted on effects of drought stress on growth and development of soybean but information is rather restricted on the limited-irrigation system by way of precaution against a long-term drought condition in the future. The experiment for limited-irrigation was conducted in transparent vinyl shelter at Asian Vegetable Research and Development Center (AVRDC), Taiwan in 1997. Two soybean varieties, Hwangkeum and AGS292, improved in Korea and AVRDC, respectively were used for this experiment. The relationships between normalized transpiration rate (NTR) and fraction of transpirable soil water (FTSW) in both varieties were similar that the NTR was unchanged until FTSW dropped to about 0.5 or 0.6. At FTSW less than those values, NTR declined rapidly. Days required to harvest in both varieties were significantly prolonged at IR6 treatment compared to any other treatments. Daily mean transpiration rate was significantly higher at IR5 treatment, as averaged over varieties. Similarly, water use efficiency was also high at 1R5 treatment. In both varieties, seed yield was the greatest at the IR5 treatment, as compared to any other limited-irrigation treatments, due to the increased seed number and high transpirational water use efficiency. The indices of input water and seed yield for the different limited-irrigation treatments against control indicated that Hwangkeum produced 59.6% or 60.7% of seed yield using 36.1% or 44.9% of input water, as compared to control, by irrigation at only R5 or R6 stages, respectively. The AGS292 produced 56.1% of seed yield with 35.4% of input water of control, when irrigated at R5 stage. The results of this study have elucidated that the limited irrigation at R5 stage in soybean can be minimized yield loss with such small quantity of water under the environment of long-term drought stress and the expected shortage of agricultural water in the future.