• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.2
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• pp.233-241
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• 2021

A series of three bench-scale experiments was performed to investigate the conversion of sodium metal to sodium chloride via reactions with non-metal and metal chlorides. Specifically, batches of molten sodium metal were separately contacted with ammonium chloride and ferrous chloride to form sodium chloride in both cases along with iron in the latter case. Additional ferrous chloride was added to two of the three batches to form low melting point consolidated mixtures of sodium chloride and ferrous chloride, whereas consolidation of a sodium-chloride product was performed in a separate batch. Samples of the products were characterized via X-ray diffraction to identify attendant compounds. The reaction of sodium metal with metered ammonium chloride particulate feeds proceeded without reaction excursions and produced pure colorless sodium chloride. The reaction of sodium metal with ferrous chloride yielded occasional reaction excursions as evidenced by temperature spikes and fuming ferrous chloride, producing a dark salt-metal mixture. This investigation into a method for controlled conversion of sodium metal to sodium chloride is particularly applicable to sodium containing elevated levels of radioactivity-including bond sodium from nuclear fuels-in remote-handled inert-atmosphere environments.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.7
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• pp.3690-3713
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• 2019

According to the main group key management schemes logical key hierarchy (LKH), exclusion basis systems (EBS) and other group key schemes are limited in network structure, collusion attack, high energy consumption, and the single point of failure, this paper presents a group key management scheme for wireless sensor networks based on Lagrange interpolation polynomial characteristic (AGKMS). That Chinese remainder theorem is turned into a Lagrange interpolation polynomial based on the function property of Chinese remainder theorem firstly. And then the base station (BS) generates a Lagrange interpolation polynomial function f(x) and turns it to be a mix-function f(x)' based on the key information m(i) of node i. In the end, node i can obtain the group key K by receiving the message f(m(i))' from the cluster head node j. The analysis results of safety performance show that AGKMS has good network security, key independence, anti-capture, low storage cost, low computation cost, and good scalability.

• Steel and Composite Structures
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• v.49 no.6
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• pp.701-711
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• 2023

In order to fully reflect variation characteristics of composite concrete dam health state, the monitoring data is applied to diagnose composite concrete dam health state. Composite concrete dam lesion development to wreckage is a precursor, and its health status can be judged. The monitoring data are generally non-linear and unsteady time series, which contain chaotic information that cannot be characterized. Thus, it could generate huge influence for the construction of monitoring models and the formulation of corresponding health diagnostic indicators. This multi-scale diagnosis process is from point to whole. Chaotic characteristics are often contained in the monitoring data. If chaotic characteristics could be extracted for reflecting concrete dam health state and the corresponding diagnostic indicators will be formulated, the theory and method of diagnosing concrete dam health state can be huge improved. Therefore, the chaotic characteristics of monitoring data are considered. And, the extracting method of the chaotic components is studied from monitoring data based on fuzzy dynamic cross-correlation factor method. Finally, a method is proposed for formulating composite concrete dam health state indicators. This method can effectively distinguish chaotic systems from deterministic systems and reflect the health state of concrete dam in service.

• Bulletin of the Korean Chemical Society
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• v.11 no.1
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• pp.25-28
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• 1990

The superconducting properties have been studied for high-Tc superconductors of the $Bi_{2-x}Mo_xSr_2Ca_2Cu_3O_y$ system (x = 0.03-0.30). The crystal structure is pseudo tetragonal with the average lattice parameters a = 5.38 ${\AA}$, b = 5.44 ${\AA}$ and c = 30.6 ${\AA}$. All samples exhibit superconductivity with Tc offset at 79 K and Tc onset at 90-115 K. The Tc onset point decreases with increasing x, but the Tc offset points are nearly the same for all samples. Scanning electron micrographs show a special growth behavior of the grains with a plate shape. It is suggested that the decrease in Tc onset points with substitution of Mo for Bi is due to the decrease in lattice parameters and to the p-orbital of Mo. It is concluded that Mo does not play a crucial role in the superconducting transition of the $Bi_2Sr_2Ca_2Cu_3O_y$ system.

• Journal of Acupuncture Research
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• v.34 no.2
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• pp.113-125
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• 2017

Objectives : Cervical herniated intervertebral disc (HIVD) are common diseases. They can be managed with acupuncture, but the evidence for effectiveness is uncertain. This review analyzed the acupuncture studies of domestic neck pain and cervical HIVD; the purpose of this study was to provide basic data useful for future research. Methods : We investigated acupuncture treatments for neck pain and cervical HIVD by searching 5 Korean Internet databases. The keywords used were "neck pain", "HIVD-cervical spine", and "nuchal pain". A total of 53 research papers (17 case reports, 16 clinical data analyses, 11 randomized controlled trials, and 9 non-randomized controlled trials) were found and analyzed according to the publication year, type of study, treatment, use of filiform needles, and type of pharmacopuncture used acupoint. The effectiveness of acupuncture treatment was determined. Results : 1. Filiform needles have been primarily used in domestic research and were used in at least half of published pharmacopuncture studies. 2. In 51 papers using filiform needles, many studies used only local acupoints; few studies used only distant acupoints. 3. All studies using pharmacopuncture were performed using local acupoints. In particular, the studies based on A-shi point, trigger point, and radiologic lesion sites were useful for multiple purposes. Conclusion : In this study, we analyzed the acupuncture contents of the domestic neck pain and HIVD-cervical spine clinical studies. This study considers the assessment of the quality and efficacy of each study, which is likely to require research that reflects the future.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.574-575
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• 2007

This paper proposes a method for choosing the best transmission system expansion plan using nodal/bus delivery marginal rate criterion ($BMR_k$) defined newly in this paper. The objective method minimizes a total cost which is an investment budget for constructing new transmission lines subject to the $BMR_k$ which means a nodal deterministic reliability level requirement at specified load point. The proposed method models the transmission system expansion problem as an integer programming problem. It solves for the optimal strategy using a branch and bound method that utilizes a network flow approach and the maximum flow-minimum cut set theorem. Test results on an existing 21-bus system are included in the paper. It demonstrated the suitability of the proposed method for solving the transmission system expansion planning problem in competitive electricity market environment.

• Journal of Microbiology and Biotechnology
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• v.1 no.2
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• pp.90-95
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• 1991

A ${\alpha}-galactosidase{\;}({\alpha}-D-galactoside$ galactohydrolase; EC 3.2.1.22) was purified from the culture filtrate of Penicillium purpurogenum by DEAE-cellulose column chromatography, gel filtration of Bio gel p-l00, and subsequent SP-Sephadex C-25 chromatography. The final preparation thus obtained showed a single band on polyacrylamide disc-gel and SDS-polyacrylamide gel electrophoresis. The molecular weight and isoelectric point were determined to be 63,000 and pH 4.0 by SDS-polyacrylamide gel electrophoresis and isoelectric focusing, respectively. The galactosidase exhibited maximum activity at pH 4.5 and $55^{\circ}C$, and was stable between pH 2 and 5, and also stable up to $40^{\circ}C$. The enzyme activity was not affected considerably by treatment with other metal compounds except mercuric chloride and silver nitrate. Copra galactomannan was finally hydrolyzed to galactose, mannose and mannobiose through the sequential actions of the purified galactosidase and mannanase from the same strain. The enzyme hydrolyzed melibiose and raffinose, but not lactose.

• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.27-29
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• 2006

This paper deals with the application of the concept of POM to analysis of power system behavior and describes a practical method of PRA for KEPCO system. This paper presents not only marginal power flow evaluation of KEPCO system in view point of physical and operation mode by using Physical and Operational Margins (POM Ver. 2.2), which is developed by V&R Energy System Research, but also by using Probabilistic Reliability Assessment (PRA Ver.3.1), which is developed by EPRI. The ability of the method to provide insights on root causes, weak points and regional causes and effects was shown. The approach offers fast and accurate determination of bottlenecks in the transmission network and optimal mitigation measures to alleviate the identified violations.

• Journal of the Korean Ceramic Society
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• v.44 no.1 s.296
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• pp.58-64
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• 2007

In this study, we investigated $Li_2ZrO_3$ membrane as a candidate material for high-temperature $CO_2$ separation and evaluated mechanical property. $Li_2ZrO_3$ powder was synthesized by solid state reaction of $Li_2CO_3\;and\;ZrO_2$. Then we fabricated $Li_2ZrO_3$ tape using tape casting method. Dense $Li_2ZrO_3$ membrane prepared by sintering at $1600^{\circ}C$ for 2 h after pressing $Li_2ZrO_3$ tape using lamination machine. Mechanical properties before and after $CO_2$ absorption of fabricated $Li_2ZrO_3$ membrane such as Hertzian indentation, Victors hardness and 3-point bending testing were evaluated.

• Journal of the Korea Institute of Building Construction
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• v.7 no.1 s.23
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• pp.79-84
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• 2007

Selection of proper root barrier as destination part of greening is very important in Root penetration resistance plan. To select proper root barrier, it need to understand composition of greening part, size, kind of plant, connection with waterproofing layer. In this point of view, we have establish greening on the roof or concrete structure, not been understand the structural mechanism. It means that we misunderstood about purpose of greening and using it. So, chosen materials and construction method was not proper for greening, it caused water leakage and decrease performance of concrete structure. Therefore, we would suggest 5 items of test methods considering environmental condition for green roof. Watertightness by water of greening part, root penetration resistance test by root penetration, bacteria resistance by must or bacteria in soil, chemical resistance by rain and chemical agent of fertilizer, and load resistance by soil depth, size of plant. These suggested test methods could be referred as guideline to test in green roof system because of not exist any performance appraisal guideline or standard. Consequently, it should be analysis as technical and institutional subdividing test methods and it need to study constantly as varied angles.