• 한국초전도ㆍ저온공학회논문지
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• 제24권3호
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• pp.57-61
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• 2022

One of the major applications of REBCO coated conductor (CC) tapes is in superconducting magnets or coils that are designed for high magnet fields. For such applications, the CC tapes were exposed to a high level of stresses which includes uniaxial tensile or transverse compressive stresses resulting from a large magnetic field. Thus, CC tapes should endure such mechanical load or deformation that can influence their electromechanical performance during manufacturing, cool-down, and operation. It has been reported that the main cause of critical current (I_c) degradation in CC tapes utilized in coil windings for superconducting magnets was the delamination due to transversely applied stresses. In most high-magnetic-field applications, the operating limits of the CC tapes will likely be imposed by the electromechanical properties together with its I_c dependence on temperature and magnetic field. In this study, we examined the influence of the transverse compressive stress on the I_c degradation behaviors in various commercially available CC tapes which is important for magnet design Four differently processed REBCO CC tapes were adopted to examine their I_c degradation behaviors under transverse compression using an anvil test method and a newly developed instantaneous I_c measurement system. As a result, all REBCO CC tapes adopted showed robustness against transverse compressive stresses for REBCO coils, notably at transverse compressive stresses until 250 MPa. When the applied stress further increased, different Ic degradation behaviors were observed depending on the sample. Among them, the one that was fabricated by the IBAD/MOCVD process showed the highest compressive stress tolerance.

• Asia Marketing Journal
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• 제20권1호
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• pp.23-48
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• 2018

SK group has been a pioneer in overall brand management and, more recently, in CSR-imbedded brand management. SK vision of "improving itself to give greater happiness to all of its customers" and the symbol mark of "Wings of Happiness" are some good examples of integrating distinct brand identities of various member companies. After impressive growth and expansions into diverse business areas, SK group is ranked as the third largest company based on asset amounts according to the Fair Trade Commission of Korea, only after Samsung and Hyundai Motor groups. SK brand management can be analyzed, using the framework of 4 stages - 'infrastructure', 'planning', 'doing', and 'seeing' stages. In order to secure 'infrastructure' of brand management system, SK has invested huge resources to the 'SK BMS' (SK Brand Management System). At the 'planning' stage, the most important task of SK like other Korean business groups is perhaps to adopt a well-organized 'brand identity (BI) system' which may consolidate brand values of individual member companies. In actuality, SK BI consists of Customer Happiness located at the center and 3 other elements of Pride, Professionalism, and Customer-orientation. At the 'doing' stage, the slogan of 'OK! SK' and the logo of 'Wings of Happiness' have been placed at the core of the SK group brand building programs. SK adopts the principle of 'independent yet united', pinpointing that each member company independently works for its business performance but it is, at the same time, encouraged to integrate its capabilities for the SK group brand. In addition, SK has sought 'shared growth' with business partners for happiness for all the members in the society. 'Social Contribution Philosophy' based on SK value of 'creation of greater happiness' is again one of the most important guidelines for CSR (corporate social responsibility) at the doing stage. At the seeing stage, SK regularly evaluates its branding programs. SK has shown some very impressive achievements in brand management: (1) a core identity of 'Customer Happiness' participating member companies may share, (2) harmonious relationships between the group brand management office and brand management divisions of member companies, and (3) consistency-keeping in brand management over time. However, there remain two major challenges: (1) globalization of SK and (2) reinforcing sustainable superiority over not only Korean rivals but also global ones.

• 한국농공학회논문집
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• 제65권3호
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• pp.57-67
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• 2023

A flash drought is a rapid-onset drought that develops over a short period of time as weather and environmental factors change rapidly, unlike general droughts, due to meteorological abnormalities. Abnormally high evapotranspiration rates and rapid declines in soil moisture increase vegetation stress. In addition, crop yields may decrease due to flash droughts during crop growth and may damage agricultural and economic ecosystems. In this study, Flash Drought Intensity Index (FDII) based on soil moisture data from Gravity Recovery Climate Experiment (GRACE) was used to analyze flash drought. FDII, which is calculated using soil moisture percentile, is expressed by multiplying two factors: the rate of intensification and the drought severity. FDII was developed for domestic flash drought events from 2014 to 2018. The flash drought that occurred in 2018, Chungcheongbuk-do showed the highest FDII. FDII was higher in heat wave flash drought than in precipitation deficit flash drought. The results of this study show that FDII is reliable flash drought analysis tool and can be applied to quantitatively analyze the characteristics of flash drought in South Korea.

• Journal of Radiation Protection and Research
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• 제47권4호
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• pp.214-225
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• 2022

Background: The conventional cerium-doped Gd₂Al₂Ga₃O₁₂ (GAGG(Ce)) scintillator-based gamma-ray imager has a bulky detector, which can lead to incorrect positioning of the gammaray source if the shielding against background radiation is not appropriately designed. In addition, portability is important in complex environments such as inside nuclear power plants, yet existing gamma-ray imager based on a tungsten mask tends to be weighty and therefore difficult to handle. Motivated by the need to develop a system that is not sensitive to background radiation and is portable, we changed the material of the scintillator and the coded aperture. Materials and Methods: The existing GAGG(Ce) was replaced with Bi₄Ge₃O₁₂ (BGO), a scintillator with high gamma-ray detection efficiency but low energy resolution, and replaced the tungsten (W) used in the existing coded aperture with lead (Pb). Each BGO scintillator is pixelated with 144 elements (12 × 12), and each pixel has an area of 4 mm × 4 mm and the scintillator thickness ranges from 5 to 20 mm (5, 10, and 20 mm). A coded aperture consisting of Pb with a thickness of 20 mm was applied to the BGO scintillators of all thicknesses. Results and Discussion: Spectroscopic characterization, imaging performance, and image quality evaluation revealed the 10 mm-thick BGO scintillators enabled the portable gamma-ray imager to deliver optimal performance. Although its performance is slightly inferior to that of existing GAGG(Ce)-based gamma-ray imager, the results confirmed that the manufacturing cost and the system's overall weight can be reduced. Conclusion: Despite the spectral characteristics, imaging system performance, and image quality is slightly lower than that of GAGG(Ce), the results show that BGO scintillators are preferable for gamma-ray imaging systems in terms of cost and ease of deployment, and the proposed design is well worth applying to systems intended for use in areas that do not require high precision.

• 한국동물학회지
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• 제21권2호
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• pp.59-66
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• 1978

1974년 8월 포항시에서 표식-방사-재채집 방법에 의한 작은 빨간집 모기 (Culex tritaeniorhynchus)의 비상 분포 및 분포 조사를 실시한 바 그 결과를 요약하면 다음과 같다. 1. 총 23,115개체의 Culex tritaneiorhynchus 암모기에 표식 방사하여 그중 120마리가 재채집되어 0.519%의 재채집율을 나타냈고 조사기간중 채집된 총 57,514마리의 암놈중 0.00208의 표식 모기 양성비를 나타냈다. 2. 방사지점으로 부터의 분산율은 0~2km에서 77.5%, 2~4km에서 11.7%, 4~6km에서 5% 그리고 6~8km에서 5.8%였다. 3. 1일간 최고 비상 거리는 7.5km였다. 1일 평균 분산거리는 1.55km였고, 방사후의 경과일수와 분산 거리와는 연관성은 보이지 않았다.

• 문화기술의 융합
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• 제9권5호
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• pp.99-104
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• 2023

본 연구는 아프로퓨처리즘에 대한 1) 이론적 고찰을 통해 지금까지 논의된 정의를 정리하여 보고, 2) 탐색적 사례연구를 통해, 3) 미래 기술 발전의 지향점과 관련해서 갖는 의의를 도출하고자 했다. 이를 위해, 먼저 아프로퓨처리즘에 관한 이론적 배경 및 개념적 논의를 살펴보고, SF문학·음악·미술 분야의 작품을 분석했다. 옥타비아 버틀러(Octavia Butler)의 SF문학은 노예제도의 과거를 들추어 세상과 마주하게 함으로써 타자화된 억압으로부터 흑인 자신들을 해방해야 한다는 사상을 확인케 한다. 자넬모네(Janelle Monae)의 음악은 기술을 통해 소수자가 외부와 관계맺을 수 있는 해방된 유토피아를 제시한다. 또한, 장 미셸 바스키아(Jean-Michel Basquiat)의 미술 작품은 흑인 예술인으로서 지금까지 배제되었던 흑인의 정체성을 재해석하고 나아가 확장된 공동체적 논의를 모색한다. 이와 같은 그들의 작업에 비추어, 본 논문은 아프리카 휴머니즘의 내재된 가치들이 기하급수적으로 발전하는 기술의 발전 속 타자와 타자의 관계 맺음으로 생성되는 공진화(共進化)의 실마리를 제공할 수 있다고 제안한다.

• FOCUS: LIFE SCIENCE
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• 제1호
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• pp.3.1-3.7
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• 2024

The article discusses the critical role of chromatography in the analysis and purification of proteins in biopharmaceuticals, emphasizing the importance of comprehensive characterization for ensuring their safety and efficacy. It highlights the use of Avantor® ACE® HPLC columns for the separation and purification of proteins, focusing on the analysis of intact proteins using reversed-phase liquid chromatography (RPLC) with fully porous particles. This article also details the application of different mobile phase additives, such as TFA and formic acid, and emphasizes the advantages of using type B ultra-pure silica-based columns for efficiency and peak shape in biomolecule analysis. Additionally, it addresses the challenges of analyzing intact proteins due to slow molecular diffusion and introduces the concept of solid-core (or superficially porous) particles, emphasizing their benefits over traditional porous particles for the analysis of therapeutic proteins. Furthermore, it discusses the development of Avantor® ACE® UltraCore BIO columns, specifically designed for the high-efficiency separation of large biomolecules, such as proteins, and demonstrates their effectiveness in achieving high-resolution separations, even for higher molecular weight proteins like monoclonal antibodies (mAbs). In addition, it underscores the complexity of analyzing and characterizing intact protein biopharmaceuticals, requiring a range of analytical techniques and the use of wide-pore stationary phases, operated at elevated temperatures and with relatively shallow gradients. It highlights the comprehensive range of options offered by Avantor® ACE® wide pore columns, including both fully porous and solid-core particles, bonded with a variety of complementary stationary phase chemistries to optimize selectivity during method development. The use of ultrapure and highly inert base silica is emphasized for enabling the use of lower concentrations of mobile phase modifiers without compromising analyte peak shape, particularly beneficial for LC-MS applications. Then the article concludes by emphasizing the significance of reversed-phase liquid chromatography and its compatibility with mass spectrometry as a valuable tool for the separation and analysis of intact proteins and their closely related variants in biopharmaceuticals.

• 사상체질의학회지
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• 제19권1호
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• pp.50-59
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• 2007

1. Objectives The Face is an important standard for the classification of Sasang Contitutions. Now We are developing 3D Automatic Face Recognition Apparatus to analyse the facial characteristics. This apparatus show us 3D image of man's face and measure facial figure. We should examine accuracy of position recognition in 3D Automatic Face Recognition Apparatus(3D-AFRA). 2. Methods We took a photograph of Face status with Land Mark by using 3D-AFRA. And We scanned Face status by using laser scanner(vivid 700). We analysed error average of distance between Facial Definition Points. We compare the average between using 3D-AFRA and using laser scanner. So We examined the accuracy of position recognition in 3D-AFRA at indirectly. 3. Results and Conclusions The error average of distance between Right Pupil and The Other Facial Definition Points is 0.5140mm and the error average of distance between Left Pupil and The Other Facial Definition Points is 0.5949mm in frontal image of face. The error average of distance between Left Pupil and The Other Facial Definition Points is 0.5308mm and the error average of distance between Left Tragion and The Other Facial Definition Points is 0.6529mm in laterall image of face. In conclusion, We assessed that accuracy of position recognition in 3D-AFRA is considerably good.

• 한국재료학회지
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• 제32권1호
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• pp.9-13
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• 2022

Bullets flying with a light from the back are called "tracers". Tracers are ignited by the combustion gas of the propellant and emit bright light that allows the shooter to visually trace the flight path. Therefore, tracers mark the firing point for allies to assist shooters to hit target quickly and accurately. Conventional tracers are constructed with a mixture of an oxidizing agent, raw metal, and organic fuel. Upon ignition, the inside of the gun can be easily contaminated by the by-products, which can lead to firearm failure during long-term shooting. Moreover, there is a fire risk such as forest fires due to residual flames at impact site. Therefore, it is necessary to develop non-combustion type luminous material; however, this material must still use the heat generated from the propellant, so-called "thermoluminescence (TL)". This study aims to compare the TL emission of Dy³⁺, La³⁺ and Ho³⁺ doped MgB₄O₇ phosphors prepared by solid state reaction. The crystal structures of samples were determined by X-ray diffraction and matched with the standard pattern of MgB₄O₇. Luminescence of various doses (200 ~ 15,000 Gy) of gamma irradiated Dy³⁺, La³⁺ and Ho³⁺ (at different concentrations of 5, 10, 15 and 20 %) doped MgB₄O₇ were recorded using a luminance/color meter. The intensity of TL yellowish (CIE x = 0.401 ~ 0.486, y = 0.410 ~ 0.488) emission became stronger as the temperature increased and the total gamma-ray dose increased.

• 한국치위생학회지
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• 제9권1호
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• pp.153-168
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• 2009

This study was executed to find out the outcome of Incremental Dental Care from September to November, 2004. 40 visitors to oral health center were examined on the oral conditions every week, seven times during above-mentioned period. Various tests were practiced in order to check their oral conditions before and after IDC such as tooth-brushing method/frequency/duration, calculus index, PHP index, halitosis and dental caries activity. Question and answer sheets were presented to student dental hygienists and 40 visitors respectively after IDC program. Results obtained are as follows. 1. Rotation method of toothbrushing increased from 27.8% to 88.9%. for men and increased from 27.3% to 95% for women. 2. Toothbrushing frequency increased from 2.8 times to 3.0 times a day for men and increased from 2.6 times to 3.1 times for women. Toothbrushing duration increased from 2.3 minutes to 2.8 minutes for men and increased from 2.1 minutes to 2.9 minutes for women. 3. Calculus index reduced from 0.5 to 0.1 for men and reduced from 0.7 to 0 for women. PHP index reduced from 3.7 to 3.0 for men and reduced 3.2 to 1.7 for women. However, halitosis didn't mark any significant difference before and after IDC. 4. Saliva buffering capacity of medium plus showed no change for men(94.5%), however increased from 95.4% to 100% for women. Dental caries activity of medium plus in S.mutans reduced by 4.3 times(72.2% to 16.7%) for men and reduced by 2 times(36.4% to 18.1%) for women. LB test results reduced by 1.5 times(50% to 33.3%) for men and reduced by 2.5 times(50% to 18.1%) for women. Alban's test results reduced by 1.4 times(83.3% to 61.1%) for men and reduced by 1.2 times(81.8% to 68.2%) for women. 5. All participants including visitors and students realized the importance of IDC and expressed a great satisfaction with IDC program. In conclusion, it is considered very necessary that IDC program should be maintained and extended to whole country so as to enhance the peoples' oral health conditions.