• Nuclear Engineering and Technology
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• v.54 no.7
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• pp.2586-2591
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• 2022

In the present work, we have irradiated the DI-BSCCO superconducting tapes with the 100 keV deuterium ions to investigate the effect of ion irradiation on their critical current (Ic). The damage simulations are carried out using the binary collision approximation method to get the spatial distribution and depth profile of the damage events in the high temperature superconducting (HTS) tape. The point defects are formed near the surface of the HTS tape. These point defects change the vortex profile in the superconducting tape. Due to the long-range interaction of vortices with each other, the Ic of the tape degrades at the 77 K and self magnetic field. The radiation dose of 2.90 MGy degrades the 44% critical current of the tape. The results of the displacement per atom (dpa) and dose deposited by the deuterium ions are used to fit an empirical relation for predicting the degradation of the Ic of the tape. We include the dpa, dose and columnar defect terms produced by the incident particles in the empirical relation. The fitted empirical relation predicts that light ion irradiation degrades the Ic in the DI-BSCCO tape at the self field. This empirical relation can also be used in neutron irradiation to predict the lifetime of the DI-BSCCO tape. The change in the Ic of the DI-BSCCO tape due to deuterium irradiation is compared with the other second-generation HTS tape irradiated with energetic radiation.

• Clean Technology
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• v.15 no.4
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• pp.233-238
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• 2009

Supercritical fluid processes have gained great attention as a new and environmentally-benign method of preparing the microparticles of energetic materials like explosives and propellants. In this work, RDX (cyclotrimethylenetrinitramine) was selected as a target explosive. The microparticle formation of RDX using supercritical anti-solvent (SAS) recrystallization process was performed and the effect of operating variables on the size and morphology of prepared particles was observed. N,N-Dimethylformamide was used as organic solvent for dissolving the RDX. The size of the RDX particles decreased remarkably up to less than $10\;{\mu}m$ by SAS recrystallization. In the range of operating conditions of the SAS process studied in this work, the finest RDX particles were obtained at 313.15K, 150 bar, and 15wt% RDX concentration in feed solution.

• Journal of The Korean Association For Science Education
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• v.36 no.1
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• pp.103-112
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• 2016

The purpose of this study is to investigate secondary science teacher's concepts of good science teaching. To do these, I have developed a questionnaire composed of 32 good teachings on education content, instructional method, instructional environment and atmosphere and assessment categories. 136 secondary science teachers have participated in the questionnaire and were requested to show agreement. Additionally, they were requested to describe the best science teachings that they have experienced. Results are as follows: First, the best science teaching that science teachers thought is a teaching that is in full accord with students' level in education content category, a teaching with an energetic interaction in instructional method category, a teaching in a trustful atmosphere in instructional environment and atmosphere category, a teaching in which students could learn something through a teaching-related assessment in assessment category. Second, secondary science teachers thought that a self-directed learning, a differentiated instruction and a teaching with diverse materials are not important factors in good science teaching. Third, there is a difference between good teaching that secondary science teachers have conceived and good teaching that they have experienced. It shows that science teachers did not precisely understand what good science teaching is. Additionally, I discussed the need of finding a case on good science teachings and a support of an interaction-focused teaching.

• Journal of Navigation and Port Research
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• v.27 no.4
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• pp.455-463
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• 2003

Time series of suspended sediment concentration, surface elevation and velocity were measured and analysed to investigate the role of waves and the predominance of infra-gravity wave component for sediment suspension phenomena in the surf zone. For the investigation in detail, we adopted the cross spectral analysis method between suspended sediment concentration and the characteristic values of wave, and ensemble average analysis method about long-period wave component, which is dominant to sediment suspension in the measurement point. The obtained results are summarized as follows: 1)The relationship between suspended sediment concentration and the characteristic values of wave is stronger for the long-period standing wave components(about 60s and 30s where the nodal point of the first mode and the anti-nodal point of the second mode are located at the measurement point, respectively) than the long wave components(about 100s), which have the most energetic power, 2) and also, it is cleared that suspended sediment concentration is increased in the case of the phase, the velocity components of the first mode long-period standing wave(60sec) were accelerated toward on-shore direction, that is, the water surface in offshore side is higher than on-shore side.

• Journal of Animal Science and Technology
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• v.47 no.4
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• pp.513-524
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• 2005

This study was conducted to introduce recycling procedures of food waste(FW) as feed according to the dehydration, semi-dehydration fermentation and liquid fermentation methods through the on-site survey of companies related, to trace physico-chemical components and nutritional losses depending upon the processing stage for each method and finally to suggest more desirable methodology for the efficient utilization of FW as animal feed. For the dehydration method, dewatering of FW alone reduced(P<0.05) moisture(approximately 10%) and ether extract contents and increased(P<0.05) fiber contents. Dewatering and subsequent dehydration of FW decreased(P<0.05) contents of ether extract, limiting amino acids such as lysine, methionine and histidine, pepsin digestibility of protein by half, and NaCl content by 40%, increased(P<0.05) contents of fiber, crude ash, Ca and P, and did not alter(P>0.05) pH. The semi-dehydration fermentation method of FW did not affect(P>0.05) the chemical components, pepsin digestibility of protein, pH and NaCl content. For the liquid fermentation method, pasteurization and fermentation of FW decreased(P<0.05) contents of dry matter, ether extract, crude fiber, lysine and NaCl; however, it did not affect(P>0.05) other chemical components, pepsin digestibility of protein and pH. Among the processing methods, nutrient losses were highest for the dehydration method(25% of metabolizable energy loss, 12% of organic matter loss) and little for the semi-dehydration and liquid fermentation methods. The on-site survey of companies related revealed that the existence of foreign materials in FW products were problematic for all the three companies surveyed, thus it was necessary to develop a more efficient screener. Before feeding FW-containing diets to pigs, high quality of protein and energy feedstuffs needed to be fortified for the dehydration method. For the semi-dehydration fermentation method, the scientific diet formulation technology was required at the initial mixing stage. For the liquid fermentation method, possibly most energetic and proteinaceous feeds needed to be supplemented for the normal animal growth.

• Science of Emotion and Sensibility
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• v.11 no.2
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• pp.139-152
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• 2008

Most marketing practitioners prospect that the beauty industry, which consists of various services and product related to the beauty, will be one of major industries in future. Thus they have been paying more attention to dramatic changes of the beauty industry. Furthermore they have been trying to differentiate their services and products from existing ones because of the tough competition in the market. For scientific marketing of the beauty services and beauty products, the beauty should be able to be measured. However marketing practitioners have no actual method to measure the beauty. In this study, we tried to find the beauty dimensions which are necessary to measure the beauty, based on Langmeyer and Shank(1994)'s study. We collected a total 258 samples as data through survey on university students, and explored the beauty dimension related to human attractiveness, and derived the implications for measuring the beauty. Based on the quantitative analysis, we derived the 4 beauty dimensions related to human attractiveness. The two of them were the inner beauty dimensions(energetic personality and thoughtful personality) whereas the others were the outer beauty dimensions(appearance and style). Additionally we analyzed if the variables, which are gender, perceived social value of beauty, and appearance satisfaction, affect on respondents' beauty perception. The empirical results showed that the beauty perception in the derived beauty dimensions is affected by the perceived social value of beauty and the appearance satisfaction: 1)The both of the inner beauty and the outer beauty are evaluated more positively when the appearance satisfaction is higher, 2)The outer beauty is evaluated more positively than the inner beauty when the perceived social value of beauty is higher.

• Applied Chemistry for Engineering
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• v.28 no.2
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• pp.214-220
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• 2017

The spherical Al/RDX/AP composites with an average size of $550{\mu}m$ were successfully prepared by drowning-out/agglomeration (D/A) process. The surface morphology and dispersion of Al particles of those composites were investigated using SEM and EDS (energy dispersive spectrometry). As a result of thermal analysis, the onset temperature of thermal decomposition of the Al/RDX/AP composites by the D/A process was found to decrease about $50^{\circ}C$ and their thermal stability was shown to be relatively enhanced due to the increase of activation energy compared to those of using the physical mixing method. In the first decomposition region of AP, Prout-Tompkins model was shown to describe well the thermal decomposition of both composites by the physical mixing and D/A process. On the other hand, in the second decomposition region of AP, the decomposition mechanisms of composites by the physical mixing and D/A process were explained by the zero-order and contracting volume model, respectively.

• Journal of the Korean Chemical Society
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• v.50 no.4
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• pp.281-290
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• 2006

The electronic structure and properties of the 1H-indene and mono-sila-1H-indene series have been investigated using basis set of 6-31G(d, p) and hybrid density functional theory. Basic measures of aromatic character derived from structure, molecular orbitals, a variety of magnetic criteria (magnetic isotropic and anisotropic susceptibilities) are considered. Energetic criteria suggest that In(Si7) enjoy conspicuous stabilization. However, by magnetic susceptibility isotropic this system are among the least aromatic of the family: Within their isomer series, In(Si4) is the most aromatic using this criteria. Natural bond orbital (NBO) analysis method was performed for the investigation of the relative stability and the nature of the 8-9 bonds in 1H-indene and mono-sila-1H-indene compounds. The results explained that how the p character of natural atomic hybrid orbital on X8 and X9 (central bond) is increased by the substitution of the C8 and C9 by Si. Actually, the results suggested that in these compounds, the X8-X9 bond lengths are closely controlled by the p character of these hybrid orbitals and also by the nature of C-Si bonds. The magnitude of the molecular stabilization energy associated to delocalization from X8-X9 and to * X8-X9 bond orbital were also quantitatively determined. Molecular orbital (MO) analysis further reveal that all structure has three delocalized MOs and two delocalized MOs and therefore exhibit the aromaticity.

• Clean Technology
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• v.23 no.2
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• pp.163-171
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• 2017

Currently, researches on recycling and reuse of waste energetic materials have recently gained a great attention from advanced countries due to ever tightening environmental regulations. In this study, as a part of a recycling technology, the experiments and dynamic simulation of simulated moving bed (SMB) process were performed to efficiently separate TNT and RDX from their mixture, which are main components of ammunition. In order to determine the operation zone of SMB process, the retention times of TNT and RDX were measured using HPLC at different flow rates and the adsorption equilibrium of each component was obtained by using a moment method. According to the adsorption equilibrium and the triangle theory of SMB process, four operation points were determined and separation experiments were carried out by the SMB process using the solvent consisting of acetonitrile and water. Two different mixing ratios (6:4 and 1:1) of acetonitrile and water were chosen for the experiment due to the great impact of mixing ratio of the solvent on separation. The performance of SMB process was evaluated by purity, recovery, productivity and solvent consumption. Pure TNT and RDX were successfully obtained from the SMB process and the dynamic simulation for the SMB process agreed well with the experimental results. Therefore, the dynamic model could be applied for predicting the dynamic behavior of the SMB process and designing a large scale SMB process.

• Journal of Korean Philosophical Society
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• no.93
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• pp.231-260
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• 2011

Simondon's theory of individuation and methodology of transduction presents a possibility of contemporary natural philosophy and a new perspective about the relation between philosophy and sciences. According to Simondon's anti-substantial viewpoint, being, as a metastable system charged with potential energy, complicates itself with quantum leaps transversing successive equilibriums. Individuation is the becoming of phases of being which transits from preindividual state to individuated states. Physical individuation as a paradigmatic model of individuation in general demonstrates not only insufficiency of form-oriented hylomorphism, but also spontaneous formational capacity of matter and reality of energetic relational operation immanent in matter. Genesis of a individual (structure or form) occurs as a resolution of the disparation between orders of magnitude, that is, the difference of potentials immanent in nature through the internal resonance, communication by information, transductive relation between the opposites. I'm trying to show that Simondon revives 'physis' of ancient natural philosophy by his own transductive applications of contemporary physics' conceptions, and therefore suggest a new non-reductive materialism. Especially Simondon's 'transduction' which is neither induction, deduction, nor dialectic, but an original ontological process and a peculiar method of thinking, I think, is worthy of note in order to construct network of knowledge and inter-relation between various sciences.