• Title/Summary/Keyword: Mass Model

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A modeling study of the process of change to a totalitarian state : The Last Man and Venezuela (전체주의 국가로의 변화과정에 대한 모형화 연구 : 최후의 인간과 베네수엘라)

  • Yoon, Hyeongho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.12
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    • pp.709-718
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    • 2020
  • Even after Fukuyama declared "The End of History" in 1989, the challenge to liberal democracy continues. Controversy about totalitarianism is constantly being raised both internally and externally in democratic countries and leaders, as well as the US-China war of supremacy. In this paper, I explored a hypothesis about the totalitarian process, and to explain this hypothesis, I analyzed the case of Venezuela, which was once referred to as a welfare model state. This paper presupposes Fukuyama's insistence on the universality of liberal democracy but considers the last man Nietzsche argues for the last man he assumes. Accordingly, the process of totalitarianism was viewed as a process in which totalitarianism was institutionalized and spread internationally through the linkage and interaction of the last fallen humans, the masses, and totalitarians in the international and domestic environments. According to this hypothesis, the Bol?var Revolution and Chavez show the process of transformation into a typical quasi-totalism. Although the Venezuelan people preferred democracy, they remained the last man who had become a man of "rich consciousness." While investigating this hypothesis, it was confirmed that extensive and interdisciplinary studies such as digital t otalitarianism and the development of science and technology should be followed.

Adsorption Characteristics of Methyl Orange on Ginkgo Shell-Based Activated Carbon (은행 껍질 기반 활성탄의 메틸오렌지 흡착 특성)

  • Lee, Jeong Moon;Lee, Eun Ji;Shim, Wang Geun
    • Applied Chemistry for Engineering
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    • v.33 no.6
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    • pp.636-645
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    • 2022
  • In this study, we investigated the adsorption characteristics of methyl orange (MO), an anionic dye, on ginkgo shell-based activated carbon (AC). For this purpose, ACs (GS-1, GS-2, and GS-4) with different textural properties were prepared using ginkgo shells and potassium hydroxide (KOH), a representative chemical activating agent. The correlation between the textural characteristics of AC prepared and the mixing ratio of KOH was investigated using nitrogen adsorption/desorption isotherms. The MO adsorption equilibrium experiment on the prepared ACs was conducted under different pH (pH 3~11) and temperature (298~318 K) conditions, and the results were investigated by Langmuir, Freundlich, Sips and temperature-dependent Sips equations. The feasibility of the MO adsorption treatment process of the prepared AC was also investigated using the dimensionless Langmuir separation factor. The heterogeneous adsorption properties of MO for the prepared AC examined using the adsorption energy distribution function (AED) were closely related to the system temperature and textural characteristics of AC. The kinetic results of the batch adsorption performed at different temperatures can be satisfactorily explained by the homogeneous surface diffusion model (HSDM), which takes into account the external mass transfer, intraparticle diffusion, and active site adsorption. The relationship between the activation energy value obtained by the Arrhenius plot and the adsorption energy distribution function value was also investigated. In addition, the adsorption process mechanism of MO on the prepared AC was evaluated using Biot number.

Factors related to the short-term and long-term intentions of healthy eating among Chinese adults living in Shanghai and parts of Anhui Province of China using the theory of planned behavior (계획적 행동이론 기반 상하이 및 안후이성 거주 중국 성인의 건강한 식행동의 장단기 의도와 관련된 요인)

  • Liu, Ani;Lee, Seungwoo;Hwang, Ji-Yun
    • Journal of Nutrition and Health
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    • v.55 no.1
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    • pp.188-199
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    • 2022
  • Purpose: This study investigated the relationship between 3 major constructs of the theory of planned behavior (TPB), i.e., attitude, subjective norms and perceived behavioral control (PBC) and past experience of healthy eating and intentions of healthy eating in the short-term and long-term in adults living in Shanghai and parts of Anhui Province, China. Methods: The online study questionnaire for this cross-sectional study was based on previously validated items. A total of 408 Chinese adults (aged 18-64 years) residing in Shanghai and parts of Anhui Province, China were included to examine relationships between 3 major constructs of TPB and past experience of healthy eating, and short-term and long-term intentions of healthy eating. Multiple linear regression model adjusted for age and body mass index (BMI) was employed to test relationships. Results: Only PBC among 3 major constructs of TPB was significantly related to short-term (p < 0.001) and long-term (p = 0.002) intention of healthy eating after adjustment for age and BMI. Past experience of healthy eating was more significantly related to long-term intention (p < 0.001) compared to short-term (p = 0.020) intention of healthy eating. The short-term and long-term intention models explained 70.5% and 48.8% of the variance, respectively. Conclusion: PBC is a potential determinant of both short-term and long-term behavioral intention of healthy eating regardless of past experience of healthy eating in adults residing in Shanghai and parts of Anhui Province, China. Our results indicate that programs promoting healthy eating to Chinese adults incorporate PCB to perform healthy eating under his or her control.

Assessment of the Applicability of Vapor Cloud Explosion Prediction Models (증기운 폭발 예측 모델의 적용성 평가)

  • Yoon, Yong-Kyun
    • Explosives and Blasting
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    • v.40 no.3
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    • pp.44-53
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    • 2022
  • This study evaluates the applicability of the TNT Equivalency Method, Multi-Energy Method, and Baker-Strehlow-Tang (BST) Method, which are blast prediction models used to determine the overpressure of blast wave generated from vapor cloud explosion. It is assumed that the propane leaked from a propane storage container with a capacity of 2000 kg installed in an area where studio houses and shopping centers are concentrated causes a vapor cloud explosion. The equivalent mass of TNT calculated by applying the TNT Equivalency Method is found to be 4061 kg. Change of overpressure with the distance obtained by the TNT Equivalency Method, Multi-Energy Method, and BST Method is rapid and the magnitude of overpressure obtained by the TNT Equivalency Method and BST method is generally similar within 100 m from explosion center. As a result of comparing the overpressure observed in the actual vapor cloud explosion case with the overpressure obtained by applying the TNT Equivalent Method, Multi-Energy Method, and BST Method, the BST Method is found to be the best fit. As a result of comparing the overpressure with the distance obtained by each explosion prediction model with the damage criteria for structure, it is estimated that the structure located within 90 m from explosion center would suffer a damage more than partial destruction, and glass panes of the structure separated by 600 m would be fractured.

Hypervelocity Impact Simulations Considering Space Objects With Various Shapes and Impact Angles (다양한 형상의 우주 물체와 충돌 각도를 고려한 우주 구조물의 초고속 충돌 시뮬레이션 연구)

  • Shin, Hyun-Cheol;Park, Jae-Sang
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.50 no.12
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    • pp.829-838
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    • 2022
  • This study conducts Hypervelocity Impact(HVI) simulations considering space objects with various shapes and different impact angles. A commercial nonlinear structural dynamics analysis code, LS-DYNA, is used for the present simulation study. The Smoothed Particle Hydrodynamic(SPH) method is applied to represent the impact phenomena with hypervelocity. Mie-Grüneisen Equation of State and Johnson-Cook material model are used to consider nonlinear structural behaviors of metallic materials. The space objects with various shapes are modeled as a sphere, cube, cylinder, and cone, respectively. The space structure is modeled as a thin plate(200 mm×200 mm×2 mm). HVI simulations are conducted when space objects with various shapes with 4.119 km/s collide with the space structures, and the impact phenomena such as a debris cloud are analyzed considering the space objects with various shapes having the same mass at the different impact angles of 0°, 30° and 45° between the space object and space structure. Although space objects have the same kinetic energy, different debris clouds are generated due to different shapes. In addition, it is investigated that the size of the debris cloud is decreased by impact angles.

Effects of Caffeine lntake and Stress on Sleep Quality in University Students (대학생의 카페인 섭취와 스트레스가 수면의 질에 미치는 영향)

  • Kim, Sang Hyeon;Gwon, Su A;Kwon, Yu Jin;Kim, Se In;Kim, Ye Jin;Oh, Hye Ran;Ha, Su Young;Cha, Nam Hyun
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.5
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    • pp.161-169
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    • 2022
  • The purpose of this study performed to confirm the effect of caffeine intake and stress on sleep quality of college students. Research respondents and data collection were conducted on 269 college students through Google questionnaires from February 14 to March 13, 2022, and the research design is a descriptive survey study. Statistical analysis was performed using the SPSS 27.0 version as t-test and one way ANOVA. As a result of the study, it was found that most college students consume more caffeine than the average daily caffeine intake of Korean adults, although it is far below the recommended daily caffeine intake of Korean adults. The quality of sleep of college students is stress (r=.32, p=<).001) and caffeine intake (r=.204, p=.001). It was found that there was a positive correlation. Factors affecting sleep quality are body mass index (β=.1.19, p<.001) Stress (β=.3.37, p<.001), smoking (β=-.18, p=.001), caffeine intake (β=.15, p=.005) It was in order, and the explanatory power of the model was 24.8%.

Numerical Study of Heat Flux and BOG in C-Type Liquefied Hydrogen Tank under Sloshing Excitation at the Saturated State (포화상태에 놓인 C-Type 액체수소 탱크의 슬로싱이 열 유속과 BOG에 미치는 변화의 수치적 분석)

  • Lee, Jin-Ho;Hwang, Se-Yun;Lee, Sung-Je;Lee, Jang Hyun
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.35 no.5
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    • pp.299-308
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    • 2022
  • This study was conducted to predict the tendency for heat exchange and boil-off gas (BOG) in a liquefied hydrogen tank under sloshing excitation. First, athe fluid domain excited by sloshing was modeled using a multiphase-thermal flow domain in which liquid hydrogen and hydrogen gas are in the saturated state. Both the the volume of fluid (VOF) and Eulerian-based multi-phase flow methods were applied to validate the accuracy of the pressure prediction. Second, it was indirectly shown that the fluid velocity prediction could be accurate by comparing the free surface and impact pressure from the computational fluid dynamics with those from the experimental results. Thereafter, the heat ingress from the external convective heat flux was reflected on the outer surfaces of the hydrogen tank. Eulerian-based multiphase-heat flow analysis was performed for a two-dimensional Type-C cylindrical hydrogen tank under rotational sloshing motion, and an inflation technique was applied to transform the fluid domain into a computational grid model. The heat exchange and heat flux in the hydrogen liquid-gas mixture were calculated throughout the analysis,, whereas the mass transfer and vaporization models were excluded to account for the pure heat exchange between the liquid and gas in the saturated state. In addition, forced convective heat transfer by sloshing on the inner wall of the tank was not reflected so that the heat exchange in the multiphase flow of liquid and gas could only be considered. Finally, the effect of sloshing on the amount of heat exchange between liquid and gas hydrogen was discussed. Considering the heat ingress into liquid hydrogen according to the presence/absence of a sloshing excitation, the amount of heat flux and BOG were discussed for each filling ratio.

Anti-Obesity Effects of Gastrodia elata Extracts on High Fat Diet-Induced Obese Mice (고지방식이 유도 비만 마우스에서 천마 추출물의 항비만 효과)

  • Kim, Ye-Seul;Kim, Ha-Rim;Park, Eun-Hee;Song, Young-Eun;Kim, Chang-Su;Ha, Won-Bae;Woo, Hyeon-Jun;Han, Yun-Hee;Lee, Jung-Han
    • Journal of Korean Medicine Rehabilitation
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    • v.32 no.4
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    • pp.1-8
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    • 2022
  • Objectives This study is to investigate the effects and mechanisms of Gastrodia elata extract (GEE) on the high-fat diet-induced obesity model. Methods C57BL/6 mice were randomly assigned into 5 groups (n=10). Control group was fed normal diet (ND). Obesity group was fed 60% high fat diet (HFD). The other three groups were fed HFD with 100, 200, 500 mg/kg GEE. After five weeks, body weight, liver and epididymal fat weight, triglyceride concentration in liver and serum, sterol regulatory element-binding protein-1 (SREBP-1), acetyl-CoA carboxylase (ACC), fatty acid synthase, peroxisome proliferator-activated receptor 𝛾 (PPAR-𝛾), CCAAT/enhancer binding protein 𝛼 (C/EBP-𝛼) expression level, insulin concentration in serum were measured. Results The GEE (100, 200, and 500 mg/kg)-treated animals exhibited substantial decreases in body mass, liver weight and epididymal white adipose tissue collate to the HFD-fed group. GEE treatment also reduced hepatic and serum triglyceride level. Furthermore, GEE treatment significantly inhibited adipogenesis in the GEE group by reducing the protein expression of SREBP-1, ACC and the messenger RNA expression of PPAR𝛾, C/EBP-𝛼, which are adipocyte differentiation-related genes. Conclusions These research outcomes recommend that GEE is possibly valuable for the prevention of HFD-induced obesity via modification of various pathways related with adipogenesis and adipocyte differentiation.

Effect of diabetes-specific oral nutritional supplements with allulose on weight and glycemic profiles in overweight or obese type 2 diabetic patients

  • Jihye Tak;Minkyung Bok;Hyunkyung Rho;Ju Hyun Park;Yunsook Lim;Suk Chon;Hyunjung Lim
    • Nutrition Research and Practice
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    • v.17 no.2
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    • pp.241-256
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    • 2023
  • BACKGROUND/OBJECTIVES: Diabetes-specific oral nutritional supplements (ONS) have anti-hyperglycemic effects, while D-allulose exerts anti-diabetic and anti-obesity effects. In this study, we investigated the efficacy and safety of diabetes-specific ONS, including allulose, on glycemic and weight changes in overweight or obese patients with type 2 diabetes mellitus (T2DM). SUBJECTS/METHODS: A single-arm, historical-control pilot clinical trial was conducted on 26 overweight or obese patients with T2DM (age range: 30-70 yrs). The participants were administered 2 packs of diabetes-specific ONS, including allulose (200 kcal/200 mL), every morning for 8 weeks. The glycemic profiles, obesity-related parameters, and lipid profiles were assessed to evaluate the efficacy of ONS. RESULTS: After 8 weeks, fasting blood glucose (FBG) level significantly decreased from 139.00 ± 29.66 mg/dL to 126.08 ± 32.00 mg/dL (P = 0.007) and glycosylated hemoglobin (HbA1c) improved (7.23 ± 0.82% vs. 7.03 ± 0.69%, P = 0.041). Moreover, the fasting insulin (δ: -1.81 ± 3.61 μU/mL, P = 0.017) and homeostasis model assessment for insulin resistance (HOMA-IR) (δ: -0.87 ± 1.57, P = 0.009) levels decreased at 8 weeks, and body weight significantly decreased from 67.20 ± 8.29 kg to 66.43 ± 8.12 kg (P = 0.008). Body mass index (BMI) also decreased in accordance with this (from 25.59 ± 1.82 kg/m2 to 25.30 ± 1.86 kg/m2, P = 0.009), as did waist circumference (δ: -1.31 ± 2.04 cm, P = 0.003). CONCLUSIONS: The consumption of diabetes-specific ONS with allulose in overweight or obese patients with T2DM improved glycemic profiles, such as FBG, HbA1c, and HOMA-IR, and reduced body weight and BMI.

Analysis of Organic Carbon Mass Balance in Daecheong Reservoir Using a Three-dimensional Numerical Model (3차원 수치 모델을 이용한 대청호 유기탄소 물질수지 해석)

  • Kim, Dong Min;An, In Kyung;Min, Kyug Seo;Chung, Se Woong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2021.06a
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    • pp.62-62
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    • 2021
  • 산업 고도화로 인하여 복잡하고 다양한 유기물의 사용량이 증가하였으며, 공공수역 내 새로운 오염물질이 유입됨에 따라 생화학적 산소요구량(BOD) 중심의 수질평가에 한계를 나타내었다. 이후 난분해성 물질을 고려한 유기물관리 정책과 총량관리의 필요성이 제기되었고 국내 하천과 호소에서는 총 유기탄소(TOC)를 유기물 관리지표로 설정하였다. 그러나 부영양 하천과 호소에서 TOC는 외부 부하뿐만아니라 식물플랑크톤의 과잉성장에 의해 증가할 수 있는 항목이므로 TOC 관리정책 추진을 위해서는 유기물의 기원에 대한 파악이 필요하다. 특히, 국내 하천에서 나타나고 있는 난분해성 유기물 오염도의 증가 추세에 대응한 실효성 있는 유기물 오염관리 정책을 수립하기 위해서는 다양한 유기물의 근원을 정확하게 파악하는 것이 매우 중요하다. 본 연구의 목적은 금강 수계 최대 상수원인 대청호를 대상으로 3차원 수리-수질 모델을 적용하여 유기탄소 성분 별 유입과 유출, 내부생성 및 소멸량을 평가하고 저수지시스템에서의 유기탄소 물질수지를 해석하는 데 있다. 유기탄소 물질수지 해석을 위해 AEM3D 모델을 사용하였으며 2017년을 대상으로 입력자료를 구축한 후 보정을 수행하였고 2018년을 대상으로 모델을 검정하였다. 모델은 유기탄소를 입자성, 용존성, 그리고 난분해성과 생분해성으로 구분하여 모의하며 유기물질 성상별 실험결과를 이용하여 입력자료를 구축하였다. 유기탄소 물질수지 해석을 위해 4가지의 탄소성분과 조류 세포 내 탄소의 질량 변화율을 계산하였다. 이를 위해 외부 유입·유출부하율, 수체 내 생성(일차생산, 재부상, 퇴적물과 수체 간 확산) 및 소멸률(POC 및 조류 침강, DOC 무기화, 탈질)을 고려하였다. 모델은 2017년과 2018년의 물수지를 적절히 재현하였으며 저수지의 성층구조를 잘 재현해내면서 전반적인 수온, 수질을 적절하게 모의하였다. 연간 TOC 부하량 중 내부기원 부하량은 2017년 68.4 %, 2018년은 높은 강우량의 영향으로 55.0%로 산정되었다. 내부 소멸 기작 중 침전으로 인한 손실이 가장 높은 것으로 나타났으며, 2017년과 2018년 각각 31.3%, 29.0%로 나타났다. TOC의 공간분포는 Chl-a 농도 분포와 유사하게 나타났으며, 댐 설치로 형성된 정체수역은 유역의 유기물 순환에 많은 영향을 미치는 것으로 평가되었다. TOC 관리 정책 기초자료 확보를 위해서는 향후 유역-저수지 시스템을 연계한 유기물 물질순환 심층 연구가 필요하다.

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