• Korean Journal of Materials Research
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• v.14 no.3
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• pp.191-195
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• 2004

Tunnel junctions with AI-N barriers fabricated by microwave-excited plasma were studied. When the Al thickness, nitridation time, and annealing temperature were 1 nm (0.8 nm), 50 s (35 s), and $280^{\circ}C$ ($300^{\circ}C$), TMR ratio and resistance-area product (RA) were 49% (34%) and $3 ${\times}$ 10^4$ $\Omega$$\mu\m^2$ ($1.5 ${\times}$ 10^4$ $\Omega$$\mu\m^2$), respectively. In order to clarify the annealing temperature dependence of TMR ratio, the local transport properties were measured for Ta 5 nm/Cu 20 nm/Ta 5 nm$29_{76}$ $Fe_{24}$ 2 nm/Cu 5 nm/M $n_{75}$$Ir_{25}$ 10 nm/ $Co_{71}$ $Co_{29}$ 4nm/Al-N junction with Al thickness of 0.8 nm and nitridation time of 35s at various temperatures. The increase of TMR ratio after annealing at $300^{\circ}C$, where the TMR ratio of the corresponding MTJ had the maximum value of 34%, can be well explained by the enhancement of the average barrier height ($\Phi_{ave}$) and the reduction of its fluctuation. After further annealing at $340^{\circ}C$, the leakage current was observed and the TMR ratio decreaseded

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2609-2615
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• 2013

A series of fluorene-carbazole copolymers containing the pendant phosphor chromophore $Ir(absn)_2(acac)$ (absn: 2-(1-naphthyl)benzothiazole; acac: acetylacetone) were designed and synthesized via Yamamoto coupling. In the film state, these copolymers exhibited absorption and emission peaks at approximately 389 and 426 nm, respectively, which originated from the fluorene backbone. However, in electroluminescent (EL) devices, a significantly red-shifted emission at approximately 611 nm was observed, which was attributed to the pendant iridium(III) complex. Using these copolymers as a single emission layer, polymer light-emitting devices with ITO/PEDOT:PSS/polymer:DNTPD/TmPyPb/LiF/Al configurations exhibited a saturated red emission at 611 nm. The attached iridium(III) complex had a significant effect on the EL performance. A maximum luminous efficiency of 0.85 cd/A, maximum external quantum efficiency of 0.77, maximum power efficiency of 0.48 lm/W, and maximum luminance of 883 $cd/m^2$ were achieved from a device fabricated with the copolymer containing the iridium(III) complex in a 2% molar ratio.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.6
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• pp.63-76
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• 2019

UAVs are unmanned, autonomous or remotely piloted aircraft. As UAVs become smaller, lighter and more economical, their applications continue to expand. Researches on UAVs in the field of remote sensing show development methods and purposes similar to those on satellite images, and they are widely used in studies such as 3D image composition and monitoring. In the field of environmental impact assessment(EIA), satellite information and data are mainly used. However, only low-resolution images covering long distances and large-scale data allowing for rough examination are being provided, so their uses are seriously limited. Therefore, in this paper, we construct spatial information of forest area by using unmanned aerial vehicle and seek efficient utilization and policy improvement in the field of environmental impact assessment. As a result, high-resolution images and data from UAVs can be used to identify the location status of SEIA, EIA, and small scale EIA project plans and to evaluate detailed environmental impact analysis. In addition, when provided together with infographics about Post-environmental impact investigation, it was confirmed that the possibility of periodic spatial information construction and evaluation can be used throughout the entire project contents and project post-process.In order to provide sophisticated infographics for the EIA, drone photography and GCP surveying methods were derived.The results of this study will be used as a basis for improving high-resolution monitoring and environmental impact assessment in the forest sector.

• Steel and Composite Structures
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• v.18 no.4
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• pp.985-1000
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• 2015

The method of cross-section analysis for different sections in a structural frame has been widely investigated since the 1960s for determination of sectional capacities of beam-columns. Many hand-calculated equations and design graphs were proposed for the specific shape and type of sections in pre-computer age decades ago. In design of many practical sections, these equations may be uneconomical and inapplicable for sections with irregular shapes, leading to the high construction cost or inadequate safety. This paper not only proposes a versatile numerical procedure for sectional analysis of beam-columns, but also suggests a method to account for residual stress and geometric imperfections separately and the approach is applied to design of high strength steels requiring axial force-moment interaction for advanced analysis or direct analysis. A cross-section analysis technique that provides interaction curves of arbitrary welded sections with consideration of the effects of residual stress by meshing the entire section into small triangular fibers is formulated. In this study, two doubly symmetric sections (box-section and H-section) fabricated by high-strength steel is utilized to validate the accuracy and efficiency of the proposed method against a hand-calculation procedure. The effects of residual stress are mostly not considered explicitly in previous works and they are considered in an explicit manner in this paper which further discusses the basis of the yield surface theory for design of structures made of high strength steels.

• Journal of Information Technology Services
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• v.15 no.3
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• pp.15-31
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• 2016

Sales Force Automation (SFA) is a strategic information system and one of the components of operational CRM system. SFA supports salespeople's activities such as selection of potential customers, creative value proposition, after-sales services, etc. SFA is increasingly used in many companies because it has the advantages to raise the salespeople's productivity by developing forecasting ability, value proposition ability, after sales service ability etc. Many researches have shown that implementation of SFA leads to the increase of salepeople performance, organizational performance, and quality of customer relationship. However, Some prior studies have discussed on the SFA implementation failure and pointed out that one of important causes of this failure is salespeople's resistance to SFA. Although many researches explain SFA acceptance phenomenon using Technology Acceptance Model (TAM) and Theory of Planned Behavior (TPB), these researches didn't deeply investigate the salespeople's resistance to SFA. Therefore, this study focuses on the factors influencing salespeople's resistance to SFA and the relationships among these factors. This study identified three factors (salespeople's perceived loss of power, perceived loss of autonomy, and perceived time and effort waste) influencing salespeople's resistance to SFA. The hypotheses testing results showed that salespeople's perceived loss of power and perceived time and effort waste significantly increased salespeople's resistance to SFA. And salespeople's perceived loss of power plays a mediating role between perceived loss of autonomy/perceived time and effort waste and salespeople's resistance to SFA. At the end of the paper, theoretical and managerial implications of this study and the limitations and future research directions are discussed.

• Journal of Korean Medical classics
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• v.30 no.1
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• pp.167-184
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• 2017

Objectives : The paper attempted to analyze the contents found in the networks of five viscera in Yixuerumen's Zangfutiaofen published by Li Chan in 1575, and tried to reveal the body structure dealt in the contents through anatomical verification. Methods : Books such as Huataxianshengneizhaotu, Tushupian, and Shisijingfahui were used to compare, understand, and interpret the original texts and annotations of Yixuerumen in an attempt to verify these through anatomy reference texts and computer programs. Results : In Yixuerumen, some contents of the networks of five viscera were revised to see feixi as not one but two, and explained the relationship of intestinal organs through heart and lung. Anatomically speaking, the networks of five viscera has a vertical structure that unfolds top to bottom centering on aorta, and has many organs connected to it such as trachea, esophagus, splenic artery, pulmonary trunk, ureter, mesentery arteriovenous, gonadal artery, and ductus deferens. Conclusions : The networks of five viscera has a great significance in that it is the fruit of much efforts where oriental medicine tried to explain not only the functions of five viscera, but also the creation and circulation of qi, blood, and bodily fluids through anatomical observation.

• Journal of Korean Medicine Rehabilitation
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• v.28 no.3
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• pp.55-66
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• 2018

Objectives To evaluate the evidence supporting the effectiveness of bee venom acupuncture for ankle sprain. Methods We conducted search across 11 electronic databases (Pubmed, EMBASE, Cochrane CENTRAL [CENTRAL], KoreaMed, Kmbase, Koreanstudies Information Service System [KISS], National Digital Science Library [NDSL], Korea Institute of Science and Technology Information [KISTI], China National Knowledge Infrastructure [CNKI], Wanfang and Chinese Scientific Journals Database [VIP] database) to find clinical trials that used bee venom acupuncture as treatment for ankle sprain. The methodological quality of randomized controlled clinical trials (RCTs) were assessed using the Cochrane Risk of Bias (RoB) tool, while non-randomized controlled clinical trials (NRCTs) were assessed using the Cochrane Risk of Bias Assessment tool for Non-randomized Study (RoBANS) tool. Results Four RCTs and one nRCT met our inclusion criteria. Almost studies showed that bee venom acupuncture has positive effect on ankle sprain. 4 studies of same intervention and control included in the meta-analysis. When comparing bee venom acupuncture and acupuncture with acupuncture, the effect size of standardized mean difference (SMD) was -0.19 (95% confidence interval [CI]: -1.95~1.56, Z=0.55, p=0.83). And when comparing bee venom acupuncture with acupuncture, the effect size of SMD was -0.17 (95% CI: -0.65~0.31, Z=0.71, p=0.48). Conclusions Although our systematic review found encouraging but limited evidence of bee venom acupuncture for ankle sprain, most of the studies included in the analysis were evaluated as methodologically high risk of bias. From now on further well-designed RCTs should be encouraged.

• Journal of Korean Medicine Rehabilitation
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• v.28 no.3
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• pp.27-38
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• 2018

Objectives The aim of this research is to analyze research trends on fracture animal experimental study in Korea. Methods For reviewing research, we constructed a key question as the effect of herbal medicine on fracture healing and selected fracture animal experimental research. We searched the following 6 databases: KoreaMed, Kmbase, Koreanstudies Information Service System (KISS), National Digital Science Library (NDSL), Korea Institute of Science and Technology Information (KISTI), Oriental Medicine Advanced Searching Integrated System (OASIS). Results A total of 283 potentially relevant studies were identified; only 12 studies were selected for reviewing research. Almost studies showed that herbal medicine had significant effect on fracture healing. Conclusions The research showed that herbal medicine could significantly stimulate fracture healing and reduced inflammation. In the future, more fracture animal experimental study should be actively conducted.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.3
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• pp.123-130
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• 2020

These experiments were to investigate the variations of rye on forage quality, productivity and β-carotene concentration affected by maturity in Pyeongchang region. Limited information are available about how forage quality and β-carotene content are affected by various factors. Samples were collected from rye harvested every 5 days, from April 25 to May 31 (April 25, April 30, May 4, May 9, May 15, May 21, May 25 and May 31). Dry matter (DM) content, plant height, DM yield and total digestible nutrient (TDN) yield increased continuously with the progressed maturity. However, crude protein (CP) content, in vitro dry matter digestibility (IVDMD) and relative feed value (RFV) decreased markedly with the delay of harvesting, while TDN content decreased from April 25 till May 15, then followed by a stable fluctuation. Conversely, acid detergent fiber (ADF) and neutral detergent fiber (NDF) value increased and then fluctuated slightly after blooming stage. For quality of plant parts, stem contained the lowest CP content and RFV value, and the highest ADF and NDF contents compared with other parts, while the grain showed the higher CP, IVDMD, RFV and lower fiber contents than others. With the plant matured, leaf proportion decreased while stem and grain proportion increased, and feed value of all the three parts decreased till blooming stage and followed by a stable phase. β-carotene concentration showed its highest on jointing stage, and then fell down sharply on the sequential stages. In conclusion, harvest around May 15 (blooming) is proper for forage rye if directly consumed by livestock as green chop in Pyeongchang under the consideration of both nutritive yield and forage quality.

• Korean Journal of Medicinal Crop Science
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• v.12 no.6
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• pp.494-499
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• 2004

A method for long-term conservation of somatic embryos of Eleutherococcus senticosos was described. Suspension cultured globular somatic embryos were successfully conservated for 36 months at $4^{\circ}C$. The embryos resumed growth within two weeks when returned to MS liquid medium containing $0.2\;mg/{\ell}$. 2,4-dichlorophenoxy acetic acid. The optimal condition for cell proliferation was achieved when somatic embryos cultured at $32^{\circ}C$ in 1/3 MS liquid medium, and about 1.2 g of embryogenic cell was induced from 150 globular embryos after 6 weeks of suspension culture. The embryogenic cells produced from these somatic embryos exhibited normal plant regeneration on auxin-free medium.