• Journal of The Korean Institute of Defense Technology
• /
• v.5 no.4
• /
• pp.1-8
• /
• 2023

In this study the economic impact of each plan for introducing Korea unclear-powered submarines were analyzed. This study conducted a preliminary investigation into foreign countries cases of unclear-powered submarines and classified three introduction plans. In order to analyze the economic impact of each introduction plan, a multiple-level survey was conducted targeting experts with experience in developing and operating ship weapon systems, and quantitative results were calculated for subcategory items with industrial relevance for industrial correlation analysis. The value added inducement coefficient and production inducement coefficient and employment inducement coefficient were calculated for each introduction method, and a favorable introduction method was derived. It is hoped that the results of this study will serve as a reference for policy decision-making during prior research for the introduction of korea nuclear submarines.

• Journal of Radiation Protection and Research
• /
• v.45 no.2
• /
• pp.76-80
• /
• 2020

Background: To improve the measurement accuracy of liquid-scintillation counting for activity standardization, it is necessary to significantly reduce the background caused by thermal noise or after-pulses. We have therefore improved a movable 3 photomultiplier (3PM)-γ coincidence-counting method using the logical sum of three double coincidences for β events. Materials and Methods: We designed a new data-acquisition system in which β events are obtained by counting the logical sum of three double coincidences. The change in β-detection efficiency can be derived by moving three photomultiplier tubes sequentially from the liquid-scintillation vial. The validity of the method was investigated by activity measurement of ¹³⁴Cs calibrated at the Korea Research Institute of Standards and Science (KRISS) with 4π(PC)β-γ(NaI(Tl)) coincidence counting using a proportional counter (PC) for the β detector. Results and Discussion: Measurements were taken over 14 counting intervals for each liquidscintillation sample by displacing three photomultiplier tubes up to 45 mm from the sample. The dead time in each β- and γ-counting channel was adjusted to be a non-extending type of 20 ㎲. The background ranged about 1.2-3.3 s^-1, such that the contributions of thermal noise or after-pulses were negligible. As the β-detection unit was moved away from the sample, the β-detection efficiencies varied between 0.54 and 0.81. The result obtained by the method at the reference date was 396.3 ± 1.7 kBq/g. This is consistent with the KRISS-certified value of 396.0 ± 2.0 kBq/g within the uncertainty range. Conclusion: The movable 3PM-γ method developed in the present work not only succeeded in reducing background counts to negligible levels but enabled β-detection efficiency to be varied by a geometrical method to apply the efficiency extrapolation method. Compared with our earlier work shown in the study of Hwang et al. [2], the measurement accuracy has much improved. Consequently, the method developed in this study is an improved method suitable for activity standardization of β-γ emitters.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.6
• /
• pp.62-71
• /
• 2013

The passive emitter location method using TDOA and FDOA measurements has higher accuracy comparing to the single TDOA or FDOA based method. Moreover, it is able to estimate the velocity vector of a moving platform. Recently, several non-iterative methods were suggested using the nuisance parameter but the common reference sensor is needed for each pair of sensors. They show also relatively low performance in the case of a long range between the sensor groups and the emitter. To solve this, we derive the estimation method of the position and velocity of a moving platform based on the Gauss-Newton method. In addition, to analyze the estimation performance of the position and velocity, respectively, we decompose the CRLB matrix into each subspace. Simulation results show the estimation performance of the derived method and the CEP planes according to the given geometry of the sensors.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.27 no.4
• /
• pp.269-274
• /
• 2007

This experiment was conducted to determine the effect of seeding method on winter survival and dry matter yield of Italian ryegrass(Lolium multiflorum Lam. "Kospeed") in paddy field for two years. The experiment was arranged in randomized complete block design with three replications. The treatment consisted of four different seeding methods, R-LS-P(rotary-line sowing-packing), R-BS-P(rotary-broadcast seeding-packing), R-BS(rotary-broadcast seeding), R-BS-TR(rotary-broadcast seeding-trifling rotary), BS-TR(broadcast seeding-trifling rotary). The emergence ratio of broadcast was decreased by 12% and winter survival was decreased by 17% compared with line sowing. The R-BS-TR treatment which was practical seeding method of rye was decreased seeding stand ratio by 65.2% and winter survival by 6.7% compared with others seeding methods. Dry matter yield of line sowing(8,151 kg/ha) was higher than that of broadcast(6,281 kg/ha) and R-BS-P treatment was the highest DM yield as 7,166 kg/ha. There was not found significant difference among seeding method in forage quality. The results of this experiment indicated that R-BS-P(rotary-broadcast seeding-packing) was recommendable the best seeding method after harvested whole crop rice in paddy field.

• Journal of KIISE
• /
• v.44 no.6
• /
• pp.587-594
• /
• 2017

Recently, motor imagery electroencephalogram(EEG) based Brain-Computer Interface(BCI) systems have received a significant amount of attention in various fields, including medicine and engineering. The Common Spatial Pattern(CSP) algorithm is the most commonly-used method to extract the features from motor imagery EEG. However, the CSP algorithm has limited applicability in Small-Sample Setting(SSS) situations because these situations rely on a covariance matrix. In addition, large differences in performance depend on the frequency bands that are being used. To address these problems, 4-40Hz band EEG signals are divided using nine filter-banks and Regularized CSP(R-CSP) is applied to individual frequency bands. Then, the Mutual Information-Based Individual Feature(MIBIF) algorithm is applied to the features of R-CSP for selecting discriminative features. Thereafter, selected features are used as inputs of the classifier Least Square Support Vector Machine(LS-SVM). The proposed method yielded a classification accuracy of 87.5%, 100%, 63.78%, 82.14%, and 86.11% in five subjects("aa", "al", "av", "aw", and "ay", respectively) for BCI competition III dataset IVa by using 18 channels in the vicinity of the motor area of the cerebral cortex. The proposed method improved the mean classification accuracy by 16.21%, 10.77% and 3.32% compared to the CSP, R-CSP and FBCSP, respectively The proposed method shows a particularly excellent performance in the SSS situation.

• Journal of Plant Biotechnology
• /
• v.40 no.1
• /
• pp.37-42
• /
• 2013

Rice is one of the most important cereal crops as a model plant for functional genomics of monocotyledons and usually transformed using Agrobacterium tumefaciens. However, the transformation's process using previous method is still time consuming and uneconomical, low efficiency. In this study, we established a new method by modifying the general Agrobacterium protocol especially in the infection and co-cultivation, Agrobacterium elimination, infected calli's selection steps using liquid media. We directly inoculated Agrobacterium containing a ZjLsL gene under the control of constitutive promoter into the 1- to 3-week-old rice calli derived from mature seeds. After 3 days of co-cultivation, the infected calli were transferred onto liquid media of Agrobacterium elimination and calli's selection for 3 days. The calli were transferred to calli's growth solid media for 14 days and then the calli transferred to shoot induction and root induction media. Putative transformants were initially selected on the medium containing phosphinothricin, and the PAT protein verified by PAT strip test. This method in this study would lead to reduction of substantial labor and time to generate transgenic plants.

• Korean Journal of Plant Resources
• /
• v.32 no.6
• /
• pp.689-697
• /
• 2019

This study describes an efficient and widely applicable droplet-vitrification following cryopreservation for shoot tips of strawberry (Fragaria × ananassa Duch.) cvs. 'Wonkyo3114' and 'Gurumi40'. The shoot tips were precultured in Murashige and Skoog (MS) liquid medium supplemented with sucrose (0.3-0.5M). Precultured explants were osmoprotected with loading solution (LS, C4) containing 20% glycerol and 20% sucrose for 40 min and exposed to dehydration solution (B5) containing 40% glycerol and 40% sucrose for 40 min at 25℃, Subsequently, the explants were transferred onto droplets containing 2.5 μL PVS3 on sterilized aluminum foils (4 cm × 0.5 cm) prior to direct immersion in liquid nitrogen (LN) for 1 h. The highest regrowth rate (%) in both the cultivars was obtained when the shoot tips were precultured with MS + 0.3M sucrose for 40 h at 25℃. The cryopreserved shoots tips exhibited 55% regrowth rate by culturing in NH₄NO₃-free MS medium supplemented with 3% sucrose, 1.0 g/L casein, 1.0 mg/L GA₃, and 0.5 mg/L BA for 5 weeks and in MS medium supplemented with 0.5 mg/L GA₃ for 8 weeks. This result shows that droplet-vitrification could be employed as a promising method for cryostorage of strawberry germplasm.

• Resources Recycling
• /
• v.16 no.3 s.77
• /
• pp.27-33
• /
• 2007

It is very important in the view point of resource recycling to recover valuable metals such as copper and tin from waste electric and electronic scrap. The waste electric and electronic scrap contains significant amounts of copper, tin, and so on. In this study, a new process for extracting copper and tin contained in the waste electric and electronic scrap using waste copper slag which is generated from the melting furnace of copper smelter was presented. Advantage of the proposed process is to reuse waste copper slag instead of new fluxes as slag formatives. In each experiment, the waste electric and electronic scrap and waste copper slag were melted inputting suitable amount of CaO as an additional flux. Up to 95% of copper and 85% of tin in the raw material were extracted in a Cu-Fe-Sn alloy phase.

• The Korean Journal of Community Living Science
• /
• v.15 no.3
• /
• pp.107-112
• /
• 2004

Many studies have showen that Letinus edodes have a reducing effects on blood pressure and lipid levels in animals with high blood pressure and hyperlipidemia. But the only cap has been on the market as goods and the stipe has been wasted. The price is very variable and is based on harvest time and the part of the plant currenty, there is not much information about the nutritional composition and bio-fuctional effects of Letinus edodes based on harvest time and part. Some farmers have been selling the powder seasoning by drying and pulverizing Letinus edodes including stipe to develop value added, late harvested Letinus edodes and its stipe these days. This study was conducted to investigate and compare the nutritional composition of Letinus edodes harvested at different times (early: E, late: L) and separated by part (cap: C, stipe: S). The 4 kinds of materials were named as early harvested cap (EC) and stipe (ES), and late harvested cap (LC) and stipe (LS) samples were obtained from Mungyeong City Agricultural Technology & Extension Center. The composition analysis of the nutrients in the 4 materials was conducted by using the AOAC method. The proximate components (moisture, protein, fat, fiber, ash, and carbohydrates), minerals and vitamin content were measured. Nutritional composition of Lentinus edodes did not show any significant difference between early and late harvested mushrooms. Nutritional compositions were different according to part. The results demonstrate that the late harvested stipe can also be used as a quality food material.

• Korean Journal of Biological Psychiatry
• /
• v.10 no.2
• /
• pp.159-167
• /
• 2003

Objective:Under the hypothesis that 5-HTTLPR polymorphism plays some role in the susceptibility or vulnerability of some subgroup of alcohol dependence, associations of 5-HTTLPR polymorphism with alcohol dependence were examined. Method:This association analysis included 109 Korean alcohol dependent and 113 Korean control subjects. DNA of all subjects were genotyped for the biallelic functional polymorphism in the 5-HTTLPR. Considering the likelihood of heterogeneity in the alcohol dependence phenotype, alcohol dependent subjects were subgrouped by onset age, family history of alcohol dependence and severity of withdrawal symptoms. Results:There were no significant differences in the frequencies of either the 5-HTTLPR genotype or the short vs. long allele in alcohol dependent and control subjects. The frequency of the S allele and S-carrier (LS or SS genotype) was significantly increased in the early onset alcohol dependent subjects and the familial alcohol dependent subjects compared with that in the control subjects. Conclusion:The results suggest that the 5-HTT 'S' promoter polymorphism is associated with an increased susceptibility or vulnerability to develop early onset alcohol dependence and familial alcohol dependence, which characterize Cloninger's type 2 alcohol dependence.