• Title/Summary/Keyword: Elasticity

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Study on the Method of Analyzing the Plasticizer of Petrochemical Products using MD-GC/MS (MD-GC/MS를 활용한 석유화학제품의 가소제(DOA, DOP) 분석방법 연구)

  • Doe, Jin-woo;Youn, Ju-min;Kang, Hyung-kyu;Hwang, In-ha;Ha, Jong-han;Na, Byung-ki
    • Journal of the Korean Applied Science and Technology
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    • v.34 no.4
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    • pp.1085-1093
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    • 2017
  • Plasticizers are materials added to give softness and elasticity to plastics having rigid properties to give soft properties as products, and they are mainly added to high molecular materials to give flexibility to improve workability and to improve cold resistance, resistance to volatility and electrical properties. It is used for the purpose. Most plasticizers are inert liquids, similar in function to solvents but with high molecular weight and no volatility. In addition, when dissolved in petrochemical products, only the plasticizer is separated by the matrix effect with other compounds, and qualitative and quantitative analysis. In this study, qualitative and quantitative analysis of DOA and DOP, which are representative components of petrochemical products, were conducted using MD-GC/MS and developed an optimal plasticizer analysis method.

Prediction of Shelf-Life of Cold Buckwheat Noodles Mixed with Vitamin D2 Enriched Siitake Mushroom and Seaweed Derived Calcium (비타민 D2 강화 표고버섯과 해조칼슘 첨가 냉면의 저장성 예측 - 연구노트 -)

  • Chung, Sook-Hyun;Oh, Hae-Sook;Yoon, Kyo-Hie
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.36 no.9
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    • pp.1225-1229
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    • 2007
  • Cold buckwheat noodles with 3% vitamin D2 enriched Siitake mushroom and seaweed derived calcium (Aquacal) added as functional ingredients were developed. For the prediction of shelf-life of these cold buckwheat noodles, classified as unsterilized cooked noodles, bacterial counts and sensory evaluations were examined during 8 days under refrigerated conditions (5oC) and 8 weeks of storage under frozen conditions $(-18^{\circ}C)$. Results of bacterial count showed that cold buckwheat noodles were microbiologically safe within 6 days at the storage temperature of $5^{\circ}C$ and the shelf-life of these noodles could be extended to 8 whole weeks when stored at $-18^{\circ}C$. Apparent qualities (off-flavor and fungi development) of cold buckwheat noodles kept in $5^{\circ}C$ were not decreased within 8 days. Sensory characteristics (gloss, mushroom flavor, bitterness, chewiness and elasticity) of noodles were not changed during 8 weeks at $-18^{\circ}C$.

A Study on Price Competitiveness for LNG Bunkering in the Busan Port (부산항의 LNG 벙커링 가격 경쟁력 확보 방안)

  • KIM, Geun-Sub
    • Journal of Korea Port Economic Association
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    • v.32 no.1
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    • pp.123-133
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    • 2016
  • LNG(Liquefied Natural Gas) bunkering has become an important issue with the enforcement of environment regulations in shipping industry required by the International Maritime Organization (IMO). With increased attention on LNG bunkering, many studies that focus on safety, regulation, demand forecasting, and the feasibility of LNG fueled ships have been carried out. However, most of the existing research has not included considerations of the price of LNG bunkering and its competitiveness. This paper, therefore, suggests ways to increase price competitiveness in the LNG bunkering market in the Busan Port. This paper analyzes the LNG bunkering supply mechanism by investigating various LNG bunkering terminal business in the LNG supply market. Factors that determine LNG bunkering price and its elasticity are also identified. Market players who want to operate LNG bunkering terminals in the Busan Port should introduce a merchandising trade method that is able to exclude the "Korea premium" in order to increase price competitiveness. This paper also suggests adoptable strategies such as the use of TPS (Terminal to Ship via Pipeline) type of bunkering service and the importance of location for minimizing initial investment cost.

Hexane Fraction of Melandrium firmum Extract Induces Laminin-332 Expression in Human Keratinocyte (각질형성세포에서 왕불유행 헥산 분획물이 Laminin-332 발현에 미치는 효과)

  • Song, Hye Jin;Kim, Mi-Sun;Lee, Hong Gu;Jin, Mu Hyun;Lee, Sang Hwa
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.42 no.2
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    • pp.173-181
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    • 2016
  • Skin basement membrane (BM) is a specialized structure that binds dermis and epidermis of the skin and plays an important role in maintaining skin structure. Structural change and destruction of BM is reported to appear due to UV exposure and aging, which may contribute to skin aging including wrinkle formation and a decrease in elasticity of the skin. One of the key components of the BM is laminin-332 (LN-332), and is a major contributor to epidermal-dermal attachment. In this study, we elucidated the effects of Meladrium firmum hexane fraction (MFHF) on LN-332 expression in HaCaT, a human keratinocyte cell line. Quantitative real-time PCR (RT-PCR) and immunoblot analysis revealed that MFHF induced upregulation of LN-332 gene and protein expression. Next, cells were treated with p38 MAPK inhibitor (SB202190) prior to MFHF treatment to analyze the signaling pathway contributing to LN-332 expression. The mRNA and protein levels of LN-332 expression were suppressed completely by pretreatment with p38 MAPK inhibitor. Furthermore, MFHF also increased the mRNA level of collagen type VII and integrin ${\alpha}6$ of skin BM component. These results collectively suggest that MFHF may have potential as an effective agent to stimulate the synthesis of BM components, and could be used to improve phenomenon of skin aging ascribed to the structural and functional impairments of BM in aged human skin.

Inhibitory Effect of Rosa multiflora hip Extract on UVB-induced Skin Photoaging in Hs68 Fibroblasts (자외선으로 유도된 Hs68 섬유아세포의 노화 반응에 대한 영실추출물의 억제 효능)

  • Park, Ji-Eun;Kim, Hyoung Ja;Kim, Su-Nam;Kang, Seung Hyun;Kim, Youn Joon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.41 no.4
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    • pp.351-359
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    • 2015
  • Acute and chronic ultraviolet (UV) irradiation triggers severe skin photoaging processes, which directly disrupt the normal three-dimensional integrity of skin. UV light stimulates the expression of matrix metalloproteinases (MMPs) which degrade constituents of extracellular matrix (ECM) proteins. These MMPs reduce collagen synthesis and decrease skin elasticity and integrity, resulting in wrinkle formation. In this study, we identified Rosa multiflora hip extract (RME) as an effective anti-photoaging ingredient. First, cell proliferation activity of RME was verified using Hs68 human dermal fibroblast cell line. RME downregulated MMPs expression through the inhibition of activator protein (AP)-1. In addition, type I and IV collagen expressions were increased with RME treatment and UVB-induced inflammatory responses were also reduced after RME treatment. In conclusion, R. multiflora hip extract may effectively improve UVB-induced skin aging and wrinkle formation which may provide as an anti-aging, anti-wrinkle, and anti-inflammation ingredient in cosmetic industry.

A Study on the Azolla imbricata using as a Cosmetic Active Ingredient (물개구리밥(Azolla imbricata)을 이용한 주요 활성성분의 분리 및 화장품 소재 개발 연구)

  • Song, Min-Hyeon;Bae, Jun-Tae;Lee, Geun-Su;Zhang, Yong-He;Pyo, Hyeong-Bae
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.36 no.1
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    • pp.71-77
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    • 2010
  • The water fern Azolla belongs to the Azollaceae and forms a symbiotic association with a $N_2$-fixing cyanobacterium, referred to as Anabaena azollae, and this association has currently been demonstrated to have potential as a nitrogen source for rice production. Because of that, Azolla fern has been used not only as organic manure in southern China and northern Vietnam for a long time but also as food for animate creatures in the underwater and decontaminant in the water. However, the phenolic compounds and active materials of Azolla have not been examined in detail in the past studies. In the present study, anti-oxidant ability test and experiment to find a particular active material of Azolla imbricata and Azolla imbricata fraction (AIF) were performed. In anti-oxidant test such as DPPH test and lipoxygenase inhibition test, the value of test represented high activities compared with authentic sample - green tea and NDGA (nordihydroguaiaretic acid). In MMP-1 test, related to collagen protection and elasticity of skin, its inhibitory effect was measured over 75 %, and the phenolic compounds of AIF related with this activity were confirmed luteolin derivatives by using FT-IR spectroscopy, element analyzer (EA) and Liquid chromatography-MASS spectroscopy.

Inhibitory Effects of Tannic acid on Human Skin Fibroblast Elastase Activity (사람의 섬유아세포 엘라스타제 활성에 대한 탄닌산의 억제 효과)

  • Lee, Ju-Eun;Kim, So-Young;Kim, Su-Yeon;Oh, Mi-Hee;Yun, Hye-Young;Baek, Kwang-Jin;Kwon, Nyoun-Soo;Kim, Dong-Seok
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.34 no.3
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    • pp.217-223
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    • 2008
  • Elastin is an important component of elastic fibers in the skin. Recently, many studies have reported that elastin is also involved In inhibiting or repairing wrinkle formation, although collagen is a major factor in the skin wrinkle formation. Elastase is a metalloproteinase which acts on degradation of elastin. It is known that elastase activity is increased by ultraviolet (UV) B radiation. Thus, Increased elastase activity could be the major reason for skin elasticity reduction and winkle formation. Tannic acid is a polyphenol found in various fruits and nuts. This molecule has a potent ability to eliminate reactive oxygen species and reactive nitrogen species. In the present study, we investigated whether tannic acid has effects on elastase activity and tropoelastin synthesis. Our results showed that tannic acid reduced elastase activity significantly in a dose-dependent manner. However, the expression of tropoelastin protein and mRNA was not significantly affected by tannic acid. From these results, we suggest that tannic acid may contribute to block tortuosity of elastic fibers by inhibiting elastase. Thus, tannic acid might be developed for a possible agent to Inhibit skin aging.

Quality Attributes of Frozen Dough Mixed with Milk Protein-Polysaccharide Materials (우유단백질과 다당류 혼합물을 첨가한 냉동반죽의 품질 특성)

  • Shon, Jin-Han;Jeung, Jeung-Il;Oh, Deog-Hwan;Kim, Jai-Moung;Eun, Jong-Bang
    • Food Science and Preservation
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    • v.16 no.4
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    • pp.518-524
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    • 2009
  • The quality attributes of frozen dough mixed with milk proteins (casein: C and whey protein: W) and polysaccharides (sodium alginate: A and ${\kappa}-carrageenan:$ K), and with 1.6% (w/w) wheat flour, were investigated to improve the quality of dough. Addition of milk protein-polysaccharide mixtures increased water absorption, as assessed by farinography, compared with control material. Dough prepared with CA and WA mixtures showed longer development times and increased valorimeter values compared with control samples. However, addition of milk protein-polysaccharide mixtures decreased dough stability, elasticity, and strength. Gelatinization temperature and the temperature at maximum viscosity, as measured by amylography, increased on addition of milk protein-polysaccharide mixtures, but the maximum viscosity decreased compared with control samples. The control showed a lower dough volume than did dough prepared with CA and WA mixtures. These results indicate that addition of milk protein-polysaccharide mixtures, especially CA and WA, improved the quality of frozen dough,and could be useful to prevent bread becoming stale.

Finite Element Analysis(fem) of The Fixed Position of the Velcro Band for the 3D Print Wrist Brace made using the Dicom File (CT Dicom 파일을 이용하여 제작한 3D Print 손목보호대용 Velcro band 고정위치의 유한요소해석(FEM))

  • Choi, Hyeun-Woo;Seo, An-Na;Lee, Jong-Min
    • Journal of the Korean Society of Radiology
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    • v.15 no.5
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    • pp.585-590
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    • 2021
  • Wrist braces are being used for patients with wrist trauma. Recently, many studies have been conducted to manufacture custom wrist braces using 3D printing technology. Such 3D printing customized orthosis has the advantage of reflecting various factors such as reflecting different shapes for each individual and securing breathability. In this paper, the stress on the orthosis by the number and position of Velcro bands that should be considered when manufacturing a 3D printing custom wrist brace was analyzed. For customized orthosis, 3D modeling of the bone and skin regions was performed using an automatic design software (Reconeasy 3D, Seeann Solution) based on CT images. Based on the 3D skin area, a wrist orthosis design was applied to suit each treatment purpose. And, for the elasticity of the brace, a wrist brace was manufactured with an FDM-type 3D printer using TPU material. To evaluate the effectiveness according to the number and position of the Velcro band of the custom 3D printed wrist brace, the stress distribution of the brace was analyzed by the finite element method (FEM). Through the finite element analysis of the wrist orthosis performed in this study, the stress distribution of the orthosis was confirmed, and the number and position of the orthosis production and Velcro bands could be confirmed. These experimental results will help provide quality treatment to patients.

Detection of Earnings Management as a Measure of Income Smoothing on Fluctuations in Exchange Rates: Managerial Implications for Korean Exporters

  • Ji, Sang-Hyun
    • Journal of Korea Trade
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    • v.23 no.6
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    • pp.66-92
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    • 2019
  • Purpose - Foreign Exchange Rates (FER) have been one of the most significant factors for both Korean exporters and the economy of Korea. The purpose of this study is to evaluate whether exporters with a high level of Exchange Rate Elasticity of Sales (ERES) make the use of earnings management for Income Smoothing (IS). Design/methodology - Income smoothing was obtained using the methodology suggested by Leuz, Nanda and Wysocki (2003). Accruals-based Earnings Management (AEM) was estimated using Discretionary Accruals (DA) calculated by the operant Jones Model developed by Dechow, Sloan and Sweeney (1995). Real Earnings Management (REM) was obtained using the methodologies suggested by Roychowdhury (2006) and Cohen and Zarowin (2010). Data were 2,402 firm years of public listed companies on the KRX, which were not in the financial industry and had a settlement of accounts in December for the period from 2013 to 2017. Findings - Results of the evaluation are as follows. First, companies with higher levels of ERES have relatively lower levels of smoothing of reported income. This might be because a fluctuation in sales caused by an exchange rate fluctuation has a direct impact on the volatility of the reported income. Second, companies with high levels of both ERES and IS have a positive correlation with both AEM and REM. This might be because companies with high levels of IS engage in earnings management to smooth reported income. Specifically, it is possible to assume that for smoothing the reported income, not only AEM but also REM is practiced. Third, companies with high levels of ERES but low levels of IS have a negative correlation with both AEM and REM. This could be interpreted as companies exhibiting low levels of IS due to higher levels of ERES tend to control IS. In addition, such results were supported by firms relying highly on exporting, and are consequently sensitive to exchange rate fluctuation. Therefore, it may conclude that companies with high levels of ERES make the use of earnings management as a means of IS. Originality/value - This study can find its significance from the fact that it is the first study, empirically verifying that companies of Korea, where exportation is a large part, use both AEM and REM as a means for smoothing reported income upon facing exchange rate fluctuations. In addition, it is highly expected that the results of this study could be useful for participants of financial markets when making IS-related decisions.