• Nuclear Engineering and Technology
• /
• v.54 no.10
• /
• pp.3957-3961
• /
• 2022

Deposition behaviors of Sr and Cs in various liquid cathodes, such as Zn, Bi, Cd, and Pb, were examined to evaluate their recovery from LiCl-KCl eutectic salt. Cations in the salt were deposited on the liquid cathode, exhibiting potential of -1.8 to -2.1 V (vs. Ag/AgCl). Zn cathode had successful deposition of Sr and exhibited the highest recovery efficiency, up to 55%. Meanwhile, the other liquid cathodes showed low current efficiencies, below 18%, indicating LiCl-KCl salt decomposition. Sr was recovered from the Zn cathode as irregular rectangular SrZn₁₃ particles. A negligible amount of Cs was deposited on the entire liquid cathode, indicating that Cs was hardly deposited on liquid cathodes. Based on these results, we propose that liquid Zn cathode can be used for cleaning Sr in LiCl-KCl salt.

• Journal of Information Processing Systems
• /
• v.18 no.4
• /
• pp.480-488
• /
• 2022

Images of tobacco retail licenses have complex unstructured characteristics, which is an urgent technical problem in the robot process automation of tobacco marketing. In this paper, a novel recognition approach using a double attention mechanism is presented to realize the automatic recognition and information extraction from such images. First, we utilized a DenseNet network to extract the license information from the input tobacco retail license data. Second, bi-directional long short-term memory was used for coding and decoding using a continuous decoder integrating dual attention to realize the recognition and information extraction of tobacco retail license images without segmentation. Finally, several performance experiments were conducted using a largescale dataset of tobacco retail licenses. The experimental results show that the proposed approach achieves a correction accuracy of 98.36% on the ZY-LQ dataset, outperforming most existing methods.

• Nuclear Engineering and Technology
• /
• v.54 no.11
• /
• pp.4280-4295
• /
• 2022

In this paper, a new multi-group neutron-gamma transport calculation code system STRAUM-MATXST for complicated geometrical problems is introduced and its development status including numerical tests is presented. In this code system, the MATXST (MATXS-based Cross Section Processor for S_N Transport) code generates multi-group neutron and gamma cross sections by processing MATXS format libraries generated using NJOY and the STRAUM (S_N Transport for Radiation Analysis with Unstructured Meshes) code performs multi-group neutron-gamma coupled transport calculation using tetrahedral meshes. In particular, this work presents the recent implementation and its test results of the Krylov subspace methods (i.e., Bi-CGSTAB and GMRES(m)) with preconditioners using DSA (Diffusion Synthetic Acceleration) and TSA (Transport Synthetic Acceleration). In addition, the Krylov subspace methods for accelerating the energy-group coupling iteration through thermal up-scatterings are implemented with new multi-group block DSA and TSA preconditioners in STRAUM.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2020.07a
• /
• pp.559-560
• /
• 2020

우리는 패션 의류 이미지의 빠르고 정확한 분류를 달성하기 위해 최적화 된 동적 감쇠 학습률과 개선 된 모델 구조를 갖춘 딥 러닝 모델을 기반으로 하는 새로운 방법을 제안했습니다. 우리는 Fashion-MNIST 데이터 셋에 대해 제안 된 모델을 사용하여 실험을 수행하고 이를 CNN, LeNet, LSTM 및 BiLSTM의 방법과 비교했습니다.

• Archives of design research
• /
• v.12 no.4
• /
• pp.327-337
• /
• 1999

As the computer technology grows so fast, it can affect the human life in every fields. Specially, advent of Digital epoch is changing human life completely. In the past, people should get the information through the mass-media. But these days we can produce and provide some information through new media, Internet. In other words, two-ways communication like internet make individual be the producer in the information stream. Especially, net generation is different form the old generation and they want to express themselves distinctively from others. Nevertheless, they can't have the chance to express their identity properly and only they try to satisfy their needs by consuming special goods. In this article, I want to suggest a program that an individual can express their own identity and image. I will transform CIP (Corporate Information Program) and adjust it to an individual case. This is different from the previous study that emphasize the external factor figure, etc. First, we will find the MI(mind identity) and the BI(behavior identity). Second, we will present the VI(visual identity) by using two factors. - MI, VI. Finally, we will analyze them totally and make the PI(personal identity ) that can express their own identity and philosophy well. Through this programs, they can express themselves well and get the chance to think creatively. I am sure this program will have more implications about image strategy.

• Journal of Korean Society of Transportation
• /
• v.27 no.6
• /
• pp.147-156
• /
• 2009

We present a methodology for modeling and solving the transit frequency design problem with variable demand. The problem is described as a bi-level model based on a non-cooperative Stackelberg game. The upper-level operator problem is formulated as a non-linear optimization model to minimize net cost, which includes operating cost, travel cost and revenue, with fleet size and frequency constraints. The lower-level user problem is formulated as a capacity-constrained stochastic user equilibrium assignment model with variable demand, considering transfer delay between transit lines. An efficient algorithm is also presented for solving the proposed model. The upper-level model is solved by a gradient projection method, and the lower-level model is solved by an existing iterative balancing method. An application of the proposed model and algorithm is presented using a small test network. The results of this application show that the proposed algorithm converges well to an optimal point. The methodology of this study is expected to contribute to form a theoretical basis for diagnosing the problems of current transit systems and for improving its operational efficiency to increase the demand as well as the level of service.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.6
• /
• pp.1211-1215
• /
• 2012

Terrestrial ecosystem are a strong sink of carbon. Forest ecosystem, one of them, has been expected to play an important role in climate changing process by absorbing atmospheric carbon dioxide. On the other hand, agricultural ecosystem that consists mainly of annual crops is regarded as poor contributor to carbon accumulation, because its production (carbon hydrate) is decomposed into carbon at a short period, which is emitted to the atmosphere. However, it is thought that fruit tree plays a great role in decreasing atmospheric carbon dioxide concentration, same as forest. Net ecosystem exchange of $CO_2$ (NEE) was measured to estimate carbon fixation capacity using an eddy covariance (EC) system method in 2 years from 2005 to 2006 at an apple orchard in Uiseong, Gyeongbuk. Average air temperature values were higher in 2006 than in 2005 during the dormant season, and lower by about $5^{\circ}C$ over the growing season causing visible cold injuries. Accordingly, we investigated long-term exchange of carbon to determine how much difference of carbon fixation capacity was shown between 2006 and 2005 in terms of environmental and plant variables such as NEE, leaf area index (LAI), and Albedo. NEE was $4.8Mg\;C\;ha^{-1}yr^{-1}$ in 2005 and $4.7Mg\;C\;ha^{-1}yr^{-1}$ in 2006, respectively. Low temperature after July in 2006 decreased LAI values faster than those in 2005. Meanwhile, Albedo values were higher after July in 2006 than in 2005. These results show that the low temperature after July in 2006 apparently affected apple growth.

• Journal of Korean Society of Transportation
• /
• v.22 no.5
• /
• pp.139-149
• /
• 2004

As the expansion of road capacity has become impractical in many urban areas, congestion pricing has been widely considered as an effective method to reduce urban traffic congestion in recent years. The principal reason is that the congestion pricing may lead the user equilibrium (UE) flow pattern to system optimum (SO) pattern in road network. In the context of network equilibrium, the link tolls according to the marginal cost pricing principle can user an UE flow to a SO pattern. Thus, the pricing method offers an efficient tool for moving toward system optimal traffic conditions on the network. This paper proposes a continuous network design program (CNDP) in network equilibrium condition, in order to find optimal congestion toll for maximizing net economic benefit (NEB). The model could be formulated as a bi-level program with continuous variable(congestion toll) such that the upper level problem is for maximizing the NEB in elastic demand, while the lower level is for describing route choice of road users. The bi-level CNDP is intrinsically nonlinear, non-convex, and hence it might be difficult to solve. So, we suggest a heuristic solution algorithm, which adopt derivative information of link flow with respect to design parameter, or congestion toll. Two example networks are used for test of the model proposed in the paper.

• Journal of Radiation Protection and Research
• /
• v.42 no.3
• /
• pp.158-165
• /
• 2017

Background: Nuclear facilities in South Korea have generally adopted pressurized ion chambers to measure ambient gamma ray exposure rates for monitoring the impact of radiation on the surrounding environment. The rates assessed with pressurized ion chambers do not distinguish between natural and man-made radiation, so a further step is needed to identify the cause of abnormal variation. In contrast, using NaI(Tl) scintillation detectors to detect gamma energy rates can allow an immediate assessment of the cause of variation through an analysis of the energy spectra. Against this backdrop, this study was conducted to propose a more effective way to monitor ambient gamma exposure rates. Materials and Methods: The following methods were used to analyze gamma energy spectra measured from January to November 2016 with NaI detectors installed at the Korea Atomic Energy Research Institute (KAERI) dormitory and Hanbat University. 1) Correlations of the variation of rates measured at the two locations were determined. 2) The dates, intervals, duration, and weather conditions were identified when rates increased by $5nSv{\cdot}h^{-1}$ or more. 3) Differences in the NaI spectra on normal days and days where rates spiked by $5nSv{\cdot}h^{-1}$ or more were studied. 4) An algorithm was derived for automatically calculating the net variation of the rates. Results and Discussion: The rates measured at KAERI and Hanbat University, located 12 kilometers apart, did not show a strong correlation (coefficient of determination = 0.577). Time gaps between spikes in the rates and rainfall were factors that affected the correlation. The weather conditions on days where rates went up by $5nSv{\cdot}h^{-1}$ or more featured rainfall, snowfall, or overcast, as well as an increase in peaks of the gamma rays emitted from the radon decay products of $^{214}Pb$ and $^{214}Bi$ in the spectrum. This study assumed that $^{214}Pb$ and $^{214}Bi$ exist at a radioactive equilibrium, since both have relatively short half-lives of under 30 minutes. Provided that this assumption is true and that the gamma peaks of the 352 keV and 1,764 keV gamma rays emitted from the radionuclides have proportional count rates, no man-made radiation should be present between the two energy levels. This study proved that this assumption was true by demonstrating a linear correlation between the count rates of these two gamma peaks. In conclusion, if the count rates of these two peaks detected in the gamma energy spectrum at a certain time maintain the ratio measured at a normal time, such variation can be confirmed to be caused by natural radiation. Conclusion: This study confirmed that both $^{214}Pb$ and $^{214}Bi$ have relatively short half-lives of under 30 minutes, thereby existing in a radioactive equilibrium in the atmosphere. If the gamma peaks of the 352 keV and 1,764 keV gamma rays emitted from these radionuclides have proportional count rates, no man-made radiation should exist between the two energy levels.

• Korean Journal of Remote Sensing
• /
• v.33 no.1
• /
• pp.15-24
• /
• 2017

Jellyfish (cnidarian) are conspicuous in many marine ecosystems when in bloom. Despite their importance for the ecosystem structure and function, very few sampling programs are dedicated to sample jellyfish because they are patchily distributed and easily clogged plankton net. Although satellite remote sensing is an excellent observing tool for many phenomena in the ocean, their uses for monitoring jellyfish are not possible due to the coarse spatial resolutions. Hence, we developed the low altitude remote sensing platform to detect jellyfish in high resolutions, which allow us to monitor not only horizontal, but also vertical migration of them. Using low altitude remote sensing platform,we measured the jellyfish from the pier at the Chesapeake Biological Laboratory in Chesapeake Bay. The patterns observed included discrete patches, in rows that were aligned with waves that propagated from deeper regions, and aggregation around physical objects. The corresponding areas of exposed jellyfish on the sea surface were $0.1{\times}10^4pixel^2$, $0.3{\times}10^4pixel^2$, and $2.75{\times}10^4pixel^2$, respectively. Thus, the research result suggested that the migration of the jellyfish was related to the physical forcing in the sea surface.