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Effects of Provitamin D on Skin Pigmentation and Immunity (프로 비타민 D 의 피부색 조절 및 면역 효능)

  • Hyunjung Choi;Daejin Min;Eun-Jeong Choi;Seung-Han Park;Hyoung-June Kim;Won-Seok Park
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.50 no.2
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    • pp.153-161
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    • 2024
  • Vitamin D is a fat-soluble vitamin that is mainly produced in the skin by UV rays. Along with melatonin, it is a representative chronobiotic substance, and the skin plays an important role in distinguishing between day and night. However, vitamin D cannot be used directly in cosmetics because it is a vitamin that acts as a coenzyme and plays a hormonal role in regulating the expression of various types of genes. Therefore, it was to investigate the skin efficacy of provitamin D (7-dehydrocholesterol), a vitamin D precursor that can be used in cosmetics. Our findings reveal that pro vitamin D can effectively inhibit the expression of tyrosinase, the melanin-producing enzyme, thereby attenuating melanin synthesis. This skin tone regulatory effect has been corroborated in vitro using artificial skin models. Additionally, pro vitamin D demonstrated anti-inflammatory properties by suppressing the expression of TNFa and, upon conversion to vitamin D through UV exposure, it was observed to induce the production of the antimicrobial peptide CAMP (LL-37). The inhibitory effect of pro vitamin D on melanin production appears to be a result of it reducing the UV absorption capacity of melanin, thereby inducing the conversion of pro D to vitamin D. Utilizing pro vitamin D in cosmetic formulations could not only modulate skin tone and enhance skin immunity but also expect to contribute to other cutaneous benefits as anti-aging and barrier function improvement with everyday UV exposure. This multifaceted efficacy positions pro vitamin D as a promising ingredient in advancing the formulation of skin care products.

Effects of impact by mechanical harvesting on storability of onions (Allium cepa L.) (기계수확 시 발생한 충격이 양파(Allium cepa L.)의 저장성에 미치는 영향)

  • Young-Kyeong Kwon;Yong-Jae Lee
    • Food Science and Preservation
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    • v.30 no.5
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    • pp.811-821
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    • 2023
  • This study investigated the storability of onions according to manual and mechanical harvesting. Moreover, we simulated the onion-to-onion impact during the mechanical harvesting process and investigated the storability after artificially subjecting the onions to impact treatment. The onion harvesting methods included hand plucking + manual collection, digger + manual, and digger + mechanical collection. The maximum impact height during the mechanical harvesting process was 0.5 m. Immediately after harvesting, no significant difference in the bruise and wound rate among the harvesting methods was observed. Any increased bruise or wound rate because of mechanical harvesting was presumed to be influenced by soil conditions, such as the presence of gravel, and machine operation factors. Furthermore, the storability during the 8.5 months storage showed no significant difference according to the harvesting methods. In treatments by simulating the impacts during the mechanical harvesting process, the impact heights were 0.0 m (0.0 J), 0.25 m (0.86 J), 0.5 m (1.72 J), and 0.75 m (2.57 J), each performed once, and four times at the same position (3.43 J) and four times at different positions (3.43 J) at 0.25 m. Throughout all the treatments, there were no significant differences in the storability during the 8.5 months storage period.

Added Value of the Sliding Sign on Right Down Decubitus CT for Determining Adjacent Organ Invasion in Patients with Advanced Gastric Cancer (진행성 위암 환자에서 인접 장기 침범을 결정하기 위한 우측와위 CT에서의 미끄러짐 징후의 추가적 가치)

  • Kyutae Jeon;Se Hyung Kim;Jeongin Yoo;Se Woo Kim
    • Journal of the Korean Society of Radiology
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    • v.83 no.6
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    • pp.1312-1326
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    • 2022
  • Purpose To investigate the added value of right down decubitus (RDD) CT when determining adjacent organ invasion in cases of advanced gastric cancer (AGC). Materials and Methods A total of 728 patients with pathologically confirmed T4a (pT4a), surgically confirmed T4b (sT4b), or pathologically confirmed T4b (pT4b) AGCs who underwent dedicated stomach-protocol CT, including imaging of the left posterior oblique (LPO) and RDD positions, were included in this study. Two radiologists scored the T stage of AGCs using a 5-point scale on LPO CT with and without RDD CT at 2-week intervals and recorded the presence of "sliding sign" in the tumors and adjacent organs and compared its incidence of appearance. Results A total of 564 patients (77.4%) were diagnosed with pT4a, whereas 65 (8.9%) and 99 (13.6%) patients were diagnosed with pT4b and sT4b, respectively. When RDD CT was performed additionally, both reviewers deemed that the area under the curve (AUC) for differentiating T4b from T4a increased (p < 0.001). According to both reviewers, the AUC for differentiating T4b with pancreatic invasion from T4a increased in the subgroup analysis (p < 0.050). Interobserver agreement improved from fair to moderate (weighted kappa value, 0.296-0.444). Conclusion RDD CT provides additional value compared to LPO CT images alone for determining adjacent organ invasion in patients with AGC due to their increased AUC values and improved interobserver agreement.

Successful Technology Investment Strategy in Manufacturing Industry: Fuzzy-set Qualitative Comparative Analysis (fsQCA) Approach (제조업에서의 성공적인 기술투자 전략에 대한 연구: 퍼지셋 질적비교분석)

  • Yunmo Koo;Juyeon Ham;Jae-Nam Lee
    • Information Systems Review
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    • v.19 no.4
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    • pp.1-25
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    • 2017
  • Despite high uncertainty on financial return, firms have continuously increased their investment on technologies because they recognize the potential value of technology investment in terms of enhancing operational efficiency and sustaining competitive advantage. Notably, an individual technology investment pattern or strategy within an industry may ultimately lead to significant differences in business performance. Hence, we first categorized technology investment into traditional research and development investment and information technology investment. Afterward, we examined the effects of each pattern with combination of the two types of technology investment on business performance according to firm size and position in the supply chain through fuzzy-set qualitative comparative analysis. Data collected from 562 manufacturing firms in Korea were used in the analysis. Results showed that large-sized firms were slightly affected with microscopic patterns in their technology investments, whereas small firms were highly affected with their technology investment patterns and their positions in the supply chain. The findings implied that a small enterprise requires an appropriate technology investment strategy to achieve successful business outcomes.

Font Change Blindness Triggered by the Text Difficulty in Moving Window Technique (움직이는 창 기법에서의 덩이글 난이도에 따른 글꼴 변화맹)

  • Seong-Jun Bak;Joo-Seok Hyun
    • Korean Journal of Cognitive Science
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    • v.34 no.4
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    • pp.259-275
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    • 2023
  • The aim of this study was to investigate font change blindness based on text difficulty in the "Moving Window Task", as originally introduced by McConkie and Rayner(1975). During the reading process where the moving window was applied, different target words in terms of font style compared to the text were presented. As participants' gaze reached the position of the target word, the font of the target word was changed to match the text font. The font of the target word before the change was either sans-serif when the text font was serif, or serif when the text font was sans-serif. After completing the reading task, more than half of the participants(62.5%) reported not detecting the font change. Observation of eye movements at the target word positions revealed that when understanding the content within the text was difficult, there was an increase in the number of regressions, an extended gaze duration, and a reduction in saccade length. Specifically, the increase in the number of regressions was evident only when the text font was serif, in other words, when the font of the target word shifted from sans-serif to serif. These results suggest that sensory interference unrelated to content understanding is not easily detected during reading. However, the possibility of detection increases when comprehension of the content becomes challenging. Furthermore, this exceptional detection possibility implies that it may be higher when the text font is serif compared to when it is sans-serif.

A study on the relationship between selective exposure, opinion change, and political participation in a digital news distribution environment (개인과 미디어의 선택성이 강화된 디지털 뉴스 유통 환경에서 선택적 노출과 의견변화, 정치참여의 관계 연구)

  • Jihee Shin;Seungchan Yang
    • The Journal of the Convergence on Culture Technology
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    • v.10 no.2
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    • pp.391-406
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    • 2024
  • The current distribution of digital news has the potential to produce politically biased information for users as a result of individual choices and media selection based on those choices. Consequently, this research explored the factors affecting individual news selection and the effects of opinion changes and political participation that can occur when news tailored to users' partisan preferences is recommended. The phenomenon of selective exposure has been shown to be stronger when individuals utilize more limited information processing, experience higher discussion efficacy among groups with similar political beliefs. Furthermore, When a selective exposure group was randomly provided with a one-way message news that matched their partisan leanings, it was found that opinion consolidation, opinion-reinforcing information processing, and online political participation. On the other hand, when they were randomly presented with two-way messaging news in which the media balanced two competing partisan positions, they were found to be more likely to understand the other side's views and arguments, and more willing to adjust their existing opinions. We are confirmed that the balanced use of various opinions is very important in deliberative democratic process.

Identification of Employee Experience Factors and Their Influence on Job Satisfaction (직원경험 요인 파악 및 직무 만족도에 끼치는 영향력 분석)

  • Juhyeon Lee;So-Hyun Lee;Hee-Woong Kim
    • Information Systems Review
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    • v.25 no.2
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    • pp.181-203
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    • 2023
  • With the fierce competition of companies for the attraction of outstanding individuals, job satisfaction of employees has been of importance. In this circumstance, many companies try to invest in job satisfaction improvement by finding employees' everyday experiences and difficulties. However, due to a lack of understanding of the employee experience, their investments are not paying off. This study examined the relationship between employee experience and job satisfaction using employee reviews and company ratings from Glassdoor, one of the largest employee communities worldwide. We use text mining techniques such as K-means clustering and LDA topic-based sentiment analysis to extract key experience factors by job level, and DistilBERT sentiment analysis to measure the sentiment score of each employee experience factor. The drawn employee experience factors and each sentiment score were analyzed quantitatively, and thereby relations between each employee experience factor and job satisfaction were analyzed. As a result, this study found that there is a significant difference between the workplace experiences of managers and general employees. In addition, employee experiences that affect job satisfaction also differed between positions, such as customer relationship and autonomy, which did not affect the satisfaction of managers. This study used text mining and quantitative modeling method based on theory of work adjustment so as to find and verify main factors of employee experience, and thus expanded research literature. In addition, the results of this study are applicable to the personnel management strategy for improving employees' job satisfaction, and are expected to improve corporate productivity ultimately.

The Contact and Parallel Analysis of SPH Using Cartesian Coordinate Based Domain Decomposition Method (Cartesian 좌표기반 동적영역분할을 고려한 SPH의 충돌 및 병렬해석)

  • Moonho Tak
    • Journal of the Korean GEO-environmental Society
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    • v.25 no.4
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    • pp.13-20
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    • 2024
  • In this paper, a parallel analysis algorithm for Smoothed Particle Hydrodynamics (SPH), one of the numerical methods for fluidic materials, is introduced. SPH, which is a meshless method, can represent the behavior of a continuum using a particle-based approach, but it demands substantial computational resources. Therefore, parallel analysis algorithms are essential for SPH simulations. The domain decomposition algorithm, which divides the computational domain into partitions to be independently analyzed, is the most representative method among parallel analysis algorithms. In Discrete Element Method (DEM) and Molecular Dynamics (MD), the Cartesian coordinate-based domain decomposition method is popularly used because it offers advantages in quickly and conveniently accessing particle positions. However, in SPH, it is important to share particle information among partitioned domains because SPH particles are defined based on information from nearby particles within the smoothing length. Additionally, maintaining CPU load balance is crucial. In this study, a highly parallel efficient algorithm is proposed to dynamically minimize the size of orthogonal domain partitions to prevent excess CPU utilization. The efficiency of the proposed method was validated through numerical analysis models. The parallel efficiency of the proposed method is evaluated for up to 30 CPUs for fluidic models, achieving 90% parallel efficiency for up to 28 physical cores.

Research on functional area-specific technologies application of future C4I system for efficient battlefield visualization (미래 지휘통제체계의 효율적 전장 가시화를 위한 기능 영역별 첨단기술 적용방안)

  • Sangjun Park;Jungho Kang;Yongjoon Lee;Jeewon Kim
    • Convergence Security Journal
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    • v.23 no.4
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    • pp.109-119
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    • 2023
  • C4I system is an integrated battlefield information system that automates the five elements of command, control, communications, computers, and information to efficiently manage the battlefield. C4I systems play an important role in collecting and analyzing enemy positions, situations, and operational results to ensure that all services have the same picture in real time and optimize command decisions and mission orders. However, the current C4I has limitations whenever a new weapon system is introduced, as it only provides battlefield visualization in a single area focusing on the battlefield situation for each military service. In a future battlefield that expands not only to land, sea, and air domains but also to cyber and space domains, improved command and control decisions will be possible if organic data from various weapon systems is gathered to quickly visualize the battlefield situation desired by the user. In this study, the visualization technology applicable to the future C4I system is divided into map area, situation map area, and display area. The technological implementation of this future C4I system is based on various data and communication means such as 5G networks, and is expected to enable hyper-connected battlefield visualization that utilizes a variety of high-quality information to enable realistic and efficient battlefield situation awareness.

A study on the effect of the pile tip deformations on the pile behaviour to shield TBM tunnelling (Shield TBM 터널시공으로 유발된 말뚝선단의 변형이 말뚝거동에 미치는 영향에 대한 연구)

  • Young-Jin Jeon;Byung-Soo Park;Young-Nam Choi;Cheol-Ju Lee
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.26 no.3
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    • pp.169-189
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    • 2024
  • In the current work, a series of three-dimensional finite element analyses have been carried out to understand the behaviour of pre-existing single piles and pile groups to adjacent Shield TBM tunnelling by considering various reinforcement conditions. The numerical modelling has analysed the effect of the pile cutting, ground reinforcement and pile cap reinforcement. The analyses concentrate on the ground settlements, the pile head settlements, the axial pile forces and the shear stress transfer mechanism at the pile-soil interface. In all cases of the pile tips supported by weathered rock, the distributions of shear stresses presented a similar trend. Also, when the pile tips were cut, tensile forces or compressive forces were induced on the piles depending on the relative positions of the piles. Furthermore, when the pile tips are supported by weathered rock, approximately 70% of the load is supported by surface friction, and only the remaining 30% is supported by the pile tip. Furthermore the final settlement of the piles without reinforcement showed approximately 70% more settlement than the piles for which ground reinforcement is considered. It has been found that the ground settlements and the pile settlements are heavily affected by the pile cutting and reinforcement conditions. The behaviour of the single pile and group piles, depending on the pile cutting, conditions of ground and pile cap reinforcement, has been extensively examined and analysed by considering the key features in great details.