• Title/Summary/Keyword: Mass changes

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Analysis of Rock Surface Roughness and Chemical Species Generation by Freeze-Thaw Experiments (동결융해 실험을 통한 암석 표면 거칠기 및 화학종 생성에 관한 분석)

  • Choi, Junghae
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.3
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    • pp.299-311
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    • 2022
  • Rocks exposed to the surface are subject to long-term weathering, and such effects weaken their engineering stability. Especially as weathering progresses, the surface of rocks will be changed by weathering, and such surface changes will affect the engineering safety of the rock mass. In addition, the chemical species produced in the weathered rock have a direct effect on the surrounding environment or on the structure. In areas where rocks are exposed, such as mining areas, chemical species produced by weathering can have a serious impact on the surrounding natural environment. In this study, accelerated weathering experiments using freeze/thaw system were conducted on rocks that had already been weathered and fresh rocks, and surface changes of each rock were observed with confocal laser scanning microscope (CLSM), and chemical species were analyzed using IC/ICP-MS. As the weathering progressed, the surface roughness decreased, and the amount of chemical species produced increased. The results of this study can be used as basic data for evaluating engineering/environmental safety in areas where rocks are exposed.

Effectiveness of a mobile health intervention on weight loss and dietary behavior changes among employees with overweight and obesity: a 12-week intervention study investigating the role of engagement

  • Imhuei Son;Jiyoun Hong;Young-Hee Han;Bo Jeong Gong;Meng Yuan Zhang;Woori Na;Cheongmin Sohn;Taisun Hyun
    • Korean Journal of Community Nutrition
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    • v.28 no.2
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    • pp.141-159
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    • 2023
  • Objectives: This study aimed to determine whether a mobile health (mhealth) intervention is effective in reducing weight and changing dietary behavior among employees with overweight and obesity. The study also investigated whether engagement with the intervention affected its effectiveness. Methods: The intervention involved the use of a dietary coaching app, a wearable device for monitoring physical activity and body composition, and a messenger app for communicating with participants and an intervention manager. A total of 235 employees were recruited for a 12-week intervention from eight workplaces in Korea. Questionnaire surveys, anthropometric measurements, and 24-h dietary recalls were conducted at baseline and after the intervention. Results: After the intervention, significant decreases in the mean body weight, body mass index, body fat percentage, and waist circumference were observed. Furthermore, the consumption frequencies of multigrain rice and legumes significantly increased, whereas those of pork belly, instant noodles, processed meat, carbonated beverages, and fast food significantly decreased compared with those at baseline. The mean dietary intake of energy and most nutrients also decreased after the intervention. When the participants were categorized into three groups according to their engagement level, significant differences in anthropometric data, dietary behaviors, and energy intake were observed following the intervention, although there were no differences at baseline, indicating that higher engagement level led to greater improvements in weight loss and dietary behavior. Conclusions: The intervention had positive effects on weight loss and dietary behavior changes, particularly among employees with higher engagement levels. These results indicate the importance of increasing the level of engagement in the intervention to enhance its effectiveness. The mhealth intervention is a promising model for health promotion for busy workers with limited time.

Floral Design Courses to Build Self-Esteem in Children Enrolled in the Community Child Care Center for Low-Income Families: Focused on the Accreditation Process of the Junior Florist Certification

  • Park, Young Hwa;Yun, Suk Young;Choi, Byung Jin;Choi, Hyun Sug
    • Journal of People, Plants, and Environment
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    • v.22 no.4
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    • pp.375-384
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    • 2019
  • The purpose of this study was to look into the influence of the junior florist training course on self-esteem of children in low-income families at the community child care center. Accordingly, the program was carried out by dividing 46 children into two groups from June 2 to August 30, 2017. The program was designed into 12 sessions of floral arrangement classes, followed by the certification test. For the program, this study set 11 flower forms focusing on line, surface, and mass arrangements as the basic forms of the western flower arrangements. For the certification test, this study had the participants take the junior florist course implemented by the Korea Ggotggozi Daegyeong Association. Seventy four percent of the total participants in this program acquired a Junior Florist Certificate. As a result, self-esteem of the experimental group significantly improved (p=.000). By items of self-esteem, the experimental group showed significant changes in social self-esteem (p=.002), familial self-esteem (p=.016), and academic self-esteem (p=.031). General self-esteem did not show a statistically significant difference, but there was an improvement by 1.9%, and this study found that there was a 5.4% change on average in social, familial, and academic self-esteem. By gender, it was found that both male (p=.003), and female participants (p=.013) showed a significant change. By grade, there were significant changes in both the lower grades (p=.014), and higher grades (p=.003).

Analysis of the Prediction of Operation Processes based on Mode of Operation for Ships: Applying Delphi method

  • HyeRi Park;JeongMin Kim
    • Journal of the Korea Society of Computer and Information
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    • v.28 no.10
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    • pp.267-275
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    • 2023
  • The digital transformation of the shipbuilding, shipping, and logistics sectors is predicted to lead to the introduction of autonomous ships and changes in the way ships are operated. The co-existence of various operation forms, such as autonomous operation and remote operation, with the existing operation methods is expected to lead to the transformation of the ship operation process and the emergence of new stakeholders. This paper studies the future ship operation process according to the change in ship operation method, predicts the change in the operating environment of future ships, and derives functional requirements by major tasks and stakeholders. The Delphi technique is applied to construct a ship operation scenario from the planning stage of voyage and cargo transport to the stage of arrival at the final destination port and discharge of cargo, and to predict future work changes by task and actor. Seafarers' activities are expected to be minimised by remote and autonomous operation, and experts in each field are expected to have responsibilities and tasks in different aspects of ship operation.

An Empirical Study on the Determinants of Korean FDI focused on China& Asean six Countries for years 2016 through 2019 (한국 기업의 해외직접투자 모형설정에 관한 실증 연구(중국&아세안6개국 중심:2016년-2019년 중심))

  • Lee eung kweon
    • Korea Trade Review
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    • v.46 no.1
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    • pp.1-21
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    • 2021
  • The main purpose of this research is to analyze the changes in investment motivation by year through time series and cross-sectional analysis of the factors and investment decisions of Korean manufacturing companies. According to the investment pattern for Asean from the 1980s to the 19th, the first expansion period was 82 to 86, the average increase in overseas investment for securing foreign raw materials due to the second oil shock, and the second expansion period was a gradual increase in exports to the U.S. in 1987 to 1996. During the first stagnation period, direct investment in Asean stagnated in the aftermath of the 1998-05 Asian crisis, and in the third expansion period, part of the production facilities invested in China were relocated to Asean, increasing Asean's investment to become Korea's largest manufacturing investment in 17. Korea's proportion of investment in Asean surpassed that of mass investment since 10 years ago, and the proportion of investment in manufacturing sector has been transferred from China to Asean, and after 17 years, it has served as an overseas production base connecting China. As such, The main purpose of the research will be to extract the determinant factors and key factors for overseas direct investment and investment patterns in conjunction with global manufacturing companies' production base relocation and investment trends through empirical analysis. This research paper gave basic reference to the motivation and determinant of investment 16 years ago, and analyzed the changes in investment motivation by year and content through empirical analysis, contributing some reasonable purpose to the decision of companies and policy makers interested in overseas direct investment.

Effects of Walking Activity Monitoring and Feedback Using Wearable Device on Body Composition and Metabolic Syndrome Risk Factors in Middle-aged Women

  • Chan-Yang Kim;Woo-Young Park
    • Journal of the Korea Society of Computer and Information
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    • v.29 no.5
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    • pp.101-110
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    • 2024
  • The purpose of this study is to analyze the effect of monitoring and feedback on walking activity using wearable devices on changes in body composition and metabolic syndrome factors in middle-aged woman. The subjects use a mobile interlocking wearable device for 6 month, feedback is provided through mobile app automatically transmitted step counter and walking activity. As a results, significantly difference shows on body weight, skeletal muscle mass, and body fat in statistically(p<.001). In changes of metabolic syndrome factor, systolic(p<.05), fasting flucose(p<.01), abdominal circumference(p<.001), TC(p<.001), and LDL-C(p<.05) are significantly difference. In conclusion, wearable devices that can be conveniently applied is an effective tool to increase walking activity and prevent metabolic syndrome of people with a sedentary lifestyle.

A large and pedunculated inflammatory pseudotumor with pseudosarcomatous change of the cecum mimicking a malignant polyp: a case report and literature review

  • Jong Suk Oh;Hyung Wook Kim;Su Bum Park;Dae Hwan Kang;Cheol Woong Choi;Su Jin Kim;Hyeong Seok Nam;Dae Gon Ryu
    • Clinical Endoscopy
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    • v.56 no.1
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    • pp.119-124
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    • 2023
  • Inflammatory pseudotumor (IPT) is a rare benign tumor of unknown etiology that can occur in almost any organ system. It has neoplastic features such as local recurrence, invasive growth, and vascular invasion, leading to the possibility of malignant sarcomatous changes. The clinical presentations of colonic IPT may include abdominal pain, anemia, a palpable mass, and intestinal obstruction. A few cases of colonic IPT have been reported, but colonic IPT with pedunculated morphology is very rare. Furthermore, since it can mimic malignant polyps, understanding the endoscopic findings of colonic IPT is important for proper treatment. Herein, we present a case of colonic IPT with pseudosarcomatous changes, presenting as a large polyp, mimicking a malignant polyp in the cecum, along with a literature review.

Evaluation by Contrast-Enhanced MR Imaging of the Lateral Border Zone in Reperfused Myocardial Infarction in a Cat Model

  • Ae Kyung Jeong;Sang Il Choi;Dong Hun Kim;Sung Bin Park;Seoung Soo Lee;Seong Hoon Choi;Tae-Hwan Lim
    • Korean Journal of Radiology
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    • v.2 no.1
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    • pp.21-27
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    • 2001
  • Objective: To identify and evaluate the lateral border zone by comparing the size and distribution of the abnormal signal area demonstrated by MR imaging with the infarct area revealed by pathological examination in a reperfused myocardial infarction cat model. Materials and Methods: In eight cats, the left anterior descending coronary artery was occluded for 90 minutes, and this was followed by 90 minutes of reperfusion. ECG-triggered breath-hold turbo spin-echo T2-weighted MR images were initially obtained along the short axis of the heart before the administration of contrast media. After the injection of Gadomer-17 and Gadophrin-2, contrast-enhanced T1-weighted MR images were obtained for three hours. The size of the abnormal signal area seen on each image was compared with that of the infarct area after TTC staining. To assess ultrastructural changes in the myocardium at the infarct area, lateral border zone and normal myocardium, electron microscopic examination was performed. Results: The high signal area seen on T2-weighted images and the enhanced area seen on Gadomer-17-enhanced T1WI were larger than the enhanced area on Gadophrin-2-enhanced T1WI and the infarct area revealed by TTC staining; the difference was expressed as a percentage of the size of the total left ventricle mass (T2= 39.2 %; Gadomer-17 =37.25 % vs Gadophrin-2 = 29.6 %; TTC staining = 28.2 %; p < 0.05). The ultrastructural changes seen at the lateral border zone were compatible with reversible myocardial damage. Conclusion: In a reperfused myocardial infarction cat model, the presence and size of the lateral border zone can be determined by means of Gadomer-17- and Gadophrin-2-enhanced MR imaging.

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Metabolomic Profiles in Patients with Cervical Cancer Undergoing Cisplatin and Radiation Therapy

  • Seo-Yeon Choi;Suin Kim;Ji-Young Jeon;Min-Gul Kim;Sun-Young Lee;Kwang-Hee Shin
    • Biomolecules & Therapeutics
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    • v.32 no.3
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    • pp.379-389
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    • 2024
  • This study was aimed to evaluate endogenous metabolic changes before and after cisplatin and radiation therapy in patients with cervical cancer via untargeted metabolomic analysis using plasma samples. A total of 13 cervical cancer patients were enrolled in this study. Plasma samples were collected from each patient on two occasions: approximately one week before therapy (P1) and after completion of cisplatin and radiation therapy (P2). Of the 13 patients, 12 patients received both cisplatin and radiation therapy, whereas one patient received radiation therapy alone. The samples were analyzed using the Ultimate 3000 coupled with Q ExactiveTM Focus Hybrid Quadrupole-OrbitrapTM mass spectrometry (Thermo Fisher Scientific, Waltham, MA, USA). Chromatographic separation utilized a Kinetex C18 column 2.1×100 mm (2.6 ㎛) (Phenomenex, Torrance, CA, USA), and the temperature was maintained at 40℃. Following P2, there were statistically significant increases in the concentrations of indoxyl sulfate, phenylacetylglutamine, Lysophosphatidyethanolamine (LysoPE) (18:1), and indole-3-acetic acid compared with the concentrations observed at P1. Specifically, in the human papillomavirus (HPV) noninfection group, indoxyl sulfate, LysoPE (18:1), and phenylacetylglutamine showed statistically significant increases at P2 compared with P1. No significant changes in metabolite concentrations were observed in the HPV infection group. Indoxyl sulfate, LysoPE (18:1), phenylacetylglutamine, and indole-3-acetic acid were significantly increased following cisplatin and radiation therapy.

A Study on Dye Variation Extracted from Dyed Textile with Gardenia degraded at HIgh temperature after X-ray Irradiation (X-선 조사 후 고온 열화된 치자 염직물에서 추출한 색소 변이 연구)

  • Da Young Youn;Hae Jin Park;Se Eun Park;Seon Hong Heo;Su Bin Lim;Yong Jae Chung
    • Journal of Radiation Industry
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    • v.18 no.1
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    • pp.53-61
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    • 2024
  • This study explores the effects of X-ray irradiation for biological control and high-temperature degradation on dye stability in dyed textiles with Gardenia. To evaluate this study, optimal extraction solvents for these textiles were identified by comparing them with a crocin standard solution. Extraction using pyridine closely matched crocin. The study then assessed the stability of X-ray irradiation and high-temperature degradation on these textiles. Transparent yellow dyes were observed in all samples. Color differences were found to increase at higher irradiation doses and longer degradation periods. While UV spectroscopy spectra showed broadening and lowering trends with higher irradiation doses and longer degradation periods, suggesting a reduction in colorant transition, mass spectrometry revealed minimal chemical changes. In conclusion, both X-ray irradiation and high-temperature degradation induced spectral changes without complete dye decomposition. Major colorants were consistently detected.