• Journal of the Korea Institute of Information Security & Cryptology
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• v.10 no.4
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• pp.81-93
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• 2000

In a methodological approach to improve the processing performance of modulo exponentiation which is the primary arithmetic in RSA crypto algorithm, we present a new RSA hardware architecture based on high-radix modulo multiplication and CRT(Chinese Remainder Theorem). By implementing the modulo multiplier using radix-16 arithmetic, we reduced the number of PE(Processing Element)s by quarter comparing to the binary arithmetic scheme. This leads to having the number of clock cycles and the delay of pipelining flip-flops be reduced by quarter respectively. Because the receiver knows p and q, factors of N, it is possible to apply the CRT to the decryption process. To use CRT, we made two s/2-bit multipliers operating in parallel at decryption, which accomplished 4 times faster performance than when not using the CRT. In encryption phase, the two s/2-bit multipliers can be connected to make a s-bit linear multiplier for the s-bit arithmetic operation. We limited the encryption exponent size up to 17-bit to maintain high speed, We implemented a linear array modulo multiplier by projecting horizontally the DG of Montgomery algorithm. The H/W proposed here performs encryption with 15Mbps bit-rate and decryption with 1.22Mbps, when estimated with reference to Samsung 0.5um CMOS Standard Cell Library, which is the fastest among the publications at present.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.5
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• pp.61-68
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• 2020

In this study, the international standard ISO TS 16774 Part 3 Test Method for Water (wash out) Resistance and KS F 4935 ｢Sealant Injection type for water leakage maintenance of adhesive flexible rubber asphalt series｣, which are standardized as a quality control method of injection type repair materials used for water leakage cracks in underground concrete structures, are currently used in Korea. As a result, considering the performance criteria of "mass change rate -0.1%" stipulated in KS F 4935, the remaining 13 types repair materials, excluding RG-2 of synthetic rubber and UG-1 of urethane, need to be reviewed for stabilization of the loss resistance due to the flow of ground water. The results of this study are determined to be available as a basic indicator for the selection of repair materials used for cracks in concrete structures. In addition, it is expected that the results of this study can be utilized as reference data that can be reflected in the improvement of the quality of repair materials that will be researched and developed later.

• Journal of the Korean earth science society
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• v.42 no.1
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• pp.1-10
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• 2021

Silicon (Si) is the second most abundant element in the crust and consists of three stable isotopes, 28Si (92.23%), 29Si (4.67%), and 30Si (3.10%). Si isotopes are widely studied worldwide as a proxy for the biogeochemical cycle of Si to reconstruct the paleoenvironment and paleoclimate. However, in Korea, there have been no studies on biogenic silica using Si isotopes. In this study, we carried out Si isotope measurements of giant diatoms, summarizing the previously reported alkali fusion methods and establishing the best Si separation method for biogenic silica. Samples were completely digested using alkali fusion at high temperatures, effectively separating Si using an AG® 50W-X8 cation exchange resin. To evaluate the precision and accuracy of our measurements, Si isotope standard material (NBS-28) and USGS reference materials (AGV-2, GSP-2, BHVO-2) were analyzed. The results are in excellent agreement with the reported values within the acceptable error. The Si isotope measurement method developed in this study is expected to help in understanding the paleoclimate and paleoenvironment by tracing the Si cycle.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.26 no.3
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• pp.185-200
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• 2021

The Marine Environment QA/QC management system has been operated since 2010 to secure the reliability of data and improve the analysis capabilities of measurement and analysis institutions. From 2010 to 2020, the cumulative number of measurement and analysis institutions participated in the QA/QC management system was 266. And the number of certificates issued by the ministry of oceans and fisheries is 182. A total of 32 reference materials for proficiency testing and interlaboratory comparisons have been developed. They were first developed focusing on items (Nutrients, COD) commonly analyzed in marine environmental measuring network, marine pollution impact surveys, sea area utilization impact assessment, deepsea water surveys, and information network on fishing ground environments. In addition, it is time to expand the filed of the QA/QC management system, such as seawater temperature, salinity, PCBs and PAHs in sediments, which are mainly analyzed in most monitoring programs. On-site assessment has been conducted for 162 laboratories according to ISO/IEC 17025 to evaluate their conformity of the quality management system and deficiency. In terms of management and technology requirements, about 4.2% of organizations showed insufficient division of duties among employees 8.7% of them revealed the lack of employee training. By test item, about 6.3% of organizations showed the lack of standard substance management and the state of the cleaning glassware was pointed out in about 5.4% of them. The QA/QC management system should be continuously supplemented by identifying the causes of nonconformities and area for improvement.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.1
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• pp.49-57
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• 2022

In order to efficiently analysis the stability of a slope, measuring the shear strength of soil is needed. The Standard Penetration Test (SPT) is not appropriate for a slope inspection due to cost and weights. One of the ways to effectively measure the N-value is the Dynamic Cone Penetration Test (DCPT). This study was performed to develop a minimized multi-function sensors that can easily estimate CPT values and Volumetric Water Content. N value with multi-fuction sensor DCPT showed -2.5 ~ +3.9% error compared with the SPT N value (reference value) in the field tests. Also, the developed multi-fuction sensor system was tested the correlation between the CPT test and the portable tester with indoor test. The test result showed 0.85 R2 value in soil, 0.83 in weathered soil, and 0.98 in mixed soil. As a result of the field test, the multi-function sensor shows the excellent field applicability of the proposed sensor system. After further research, it is expected that the portable multi-function sensor will be useful for general slope inspection.

• Journal of Korea Entertainment Industry Association
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• v.14 no.4
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• pp.265-288
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• 2020

Public sports facilities, which have increased in number due to continued government attention and investment, are used by a large number of residents in the province. However, the safety management in some facilities is limited due to being carried out with reference to safety management standard manuals as a mere formality. The purpose of this study was to analyze the current safety management status of public sports facilities in Gangwon and to seek out a policy direction that can be used safely by provincial residents. To this end. the study made a comprehensive review of central government and Gangwon government policy trends in sports facility safety management in Gangwon along with actual cases, from which it made the following suggestions for policy directions. First, it proposed the designation and operation of specialized institutions using locally established development and municipal companeie,. universities and cooperatives. and the training and fostering of safety managers for sports facilities. Secod, it proposed the establishment of a foundation to promote a sport facility safety culture such as designation of and commendation for excellent facility safety management on the provincial level. holding case presentations on safety and responsiveness. sports safety experience plazas, sports safety classes, and cartoons for public relations. Third, it proposed setting the foundation for a safety management system that takes into account the greater quantity of leisure sports facilities compared to other cities and provinces. Fourth, it proposed the establishment of an institutional basis to establish support ordinance for sports facility safety management that meets the local conditions in Gangwon. Fifth, it proposed safety management measures for sports facilities at the central government level in parallel with a basic plan for sports facility safety management tailored to Gangwon that matches the conditions on the ground in the region.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.4
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• pp.457-467
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• 2022

Electron bombardment to silicate glass during electron probe microanalysis (EPMA) causes outward migration of Na from the excitation volume and subsequent decrease in the measured X-ray count rates of Na. To acquire precise Na₂O content of silicate glass, one should use proper analytical technique to avoid or minimize Na migration effect or should correct for decreases in the measured Na X-ray counts. In this study, we analyzed 8 silicate glass standard samples using automated Time Dependent Intensity (TDI) correction method of Probe for EPMA software that can calculate zero-time intercept by extrapolating X-ray count changes over analysis time. We evaluated an accuracy of TDI correction for Na measurements of silicate glasses with EPMA at 15 kV acceleration voltage and 20 nA probe current electron beam, which is commonly utilized analytical condition for geological samples. Results show that Na loss can be avoided with 20 ㎛-sized large beam (<0.1 nA/㎛²), thus silicate glasses can be analyzed without TDI correction. When the beam size is smaller than 10 ㎛, Na loss results in large relative errors up to -55% of Na₂O values without correction. By applying TDI corrections, we can acquire Na₂O values close to the reference values with relative errors of ~ ±10%. Use of weighted linear-fit can reduce relative errors down to ±6%. Thus, quantitative analysis of silicate glasses with EPMA is required for TDI correction for alkali elements such as Na and K.

• Korean Journal of Pharmacognosy
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• v.53 no.4
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• pp.226-233
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• 2022

Ephedra herbs are defined as stem of Ephedra sinica , Ephedra intermedia and Ephedra equisetina in the Korean Pharmacopoeia. It is important to use pure herbs to derive the safety and efficacy of herbal medicine. However, the identification of these herbs by conventional taxonomic methods is difficult. Recently, many studies have applied these DNA barcoding for the identification of herbal medicinal species using standard DNA markers. In this study, we report a case study in which the identification of Ephedra species was done by DNA barcoding. For identification of Ephedra species, 17 samples were collected, and a reference DNA barcode library was developed using 6 markers (rbcL, matK, ITS2, ycf1, ycf3, and rpoC2). To develop KASP-SNP markers, we selected 4 markers (ycf1, ycf3, rpl2, and rbcL), which were able to distinguish three Ephedra species. In the result, the specific markers for each of the three Ephedra were clustered into FAM-positive section, whereas non-targeted plants were clustered either HEX-positive or negative section. Therefore, we have developed KASP assay that allow rapid and easy Ephedra species identification using three KASP markers.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.6
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• pp.239-245
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• 2022

Reduced graphene oxide (rGO) has attracted many attention and applications due to its excellent electrochemical ability. Therefore, standardization of rGO through structural and thermal analysis facilitates quality improvement and management, enabling users to increase efficiency and reduce relevant costs. For rGO and graphene-related materials, it is very important to determine the number of layers and define the resulting difference in physical properties. In this study, 3~4 layers of rGO-1 and 9~10 layers of rGO-2 were obtained from graphene oxide (GO) through a hydrazine reduction process. For the prepared rGOs, X-ray diffraction (XRD) pattern obtained a diffraction peak at 2θ≈25° related to (002) reflection was used to calculate the layer numbers by determining interlayer distance and FWHM value. To reduce the angular uncertainty, XRD data analysis was performed with angle correction using standard reference materials for X-ray powder diffraction analysis. Precise interlayer distance and number of layers were determined using OriginLab and open-source XRD diffraction analysis programs using the angle-corrected diffraction data. TG-DSC thermal analysis was performed to further standardize the physical properties of rGO samples.

• Journal of Internet Computing and Services
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• v.22 no.6
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• pp.115-127
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• 2021

With the development of science and technology around the world, the realm of cyberspace, following land, sea, air, and space, is also recognized as a battlefield area. Accordingly, it is necessary to design and establish various elements such as definitions, systems, procedures, and plans for not only physical operations in land, sea, air, and space but also cyber operations in cyberspace. In this research, the importance of cyber targets that can be considered when prioritizing the list of cyber targets selected through intermediate target development in the target development and prioritization stage of targeting processing of cyber operations was selected as a factor to be considered. We propose a method to calculate the score for the cyber target and use it as a part of the cyber target prioritization score. Accordingly, in the cyber target prioritization process, the cyber target importance category is set, and the cyber target importance concept and reference item are derived. We propose a TIR (Target Importance Rank) algorithm that synthesizes parameters such as Event Prioritization Framework based on PageRank algorithm for score calculation and synthesis for each derived standard item. And, by constructing the Stuxnet case-based network topology and scenario data, a cyber target importance score is derived with the proposed algorithm, and the cyber target is prioritized to verify the proposed algorithm.