• Title/Summary/Keyword: 회전율

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Influences of Die Temperature and Repeated Extrusion on Physical Properties of Extruded White Ginseng (사출구 온도와 반복 압출성형이 백삼압출성형물의 물리적 특성에 미치는 영향)

  • Choi, Kwan-Hyung;Ryu, Gi-Hyung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.6
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    • pp.921-927
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    • 2015
  • The aim of this study was to investigate the effect of die temperature and repeated extrusion on physical properties of extruded white ginseng (EWG). The die temperature was adjusted to 100, 120, and $140^{\circ}C$, and extrusion was repeated under the same conditions with their corresponding samples. Specific mechanical energy input decreased as die temperature increased during extrusions. The secondary extruded white ginseng (SEWG) at a die temperature of $120^{\circ}C$ showed a higher expansion index than other extrudates. Elevation of both die temperature and repeated extrusion increased the specific length of extrudates. The highest apparent elastic modulus, breaking strength, and water solubility index obtained from SEWG at a die temperature of $100^{\circ}C$ were $7.53{\times}10^8N/m^2$, $7.49{\times}10^5N/m^2$, and 39.02%, respectively. When die temperature increased, water absorption index (WAI) decreased. The WAI of SEWG was higher than that of EWG. In conclusion, repeated extrusion affected physical properties of white ginseng and could be applied to produce improved quality of ginseng products.

Effects of Die Temperature and CO2 Injection on Physical Properties and Antioxidant Activity of Extruded Rice with Tomato Flour (사출구 온도와 CO2 주입이 쌀·토마토 압출성형물의 물리적 특성 및 항산화 활성에 미치는 영향)

  • An, Sang-Hee;Ryu, Gi-Hyung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.6
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    • pp.912-920
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    • 2015
  • The study was designed to investigate the effects of die temperature and $CO_2$ injection on the physical and antioxidant properties of extruded rice with tomato flour. Moisture content and screw speed were fixed at 25% and 150 rpm, respectively. Die temperatures and $CO_2$ injection were adjusted to 80, 110, and $140^{\circ}C$ and 0, and 300 mL/min, respectively. Specific mechanical energy input decreased as die temperature increased from 80 to $140^{\circ}C$. The expansion index increased, while bulk density decreased with $CO_2$ injection. All extrudates showed increased water soluble index (WSI) and water absorption index through the extrusion process. WSI increased as die temperature increased. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and total phenolic compounds increased as die temperature increased from 80 to $140^{\circ}C$. Total carotenoid and lycopene contents decreased through the extrusion process. Total carotenoid and lycopene contents upon 0 mL/min $CO_2$ injection and $140^{\circ}C$ die temperature were highest at $6.65{\mu}g/g$ and 2.69 mg/kg, respectively. In conclusion, $CO_2$ injection affects expansion properties while an increased die temperature leads to increased DPPH radical scavenging activity and total phenols.

The Oral Health Behaviors for Children and Teachers by Teacher-Supervised Toothbrushing in Community Child Center (지역아동센터 교사의 칫솔질 지도여부에 따른 아동과 교사의 구강보건행태)

  • Shin, Sun-Jung;Jang, Jung-Yoo;Kim, Chang-Hee
    • Journal of dental hygiene science
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    • v.12 no.6
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    • pp.572-582
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    • 2012
  • The purpose of this research was to compare the oral health behaviors for children and teachers in toothbrushing facilities installed community child center related with teacher-supervised toothbrushing. This research was follow-up study from the Korean Dental Hygienists Association third project '2010 program of making of the diamond tooth'. 266 child support teachers were invited and 201 were included in the study (response rate: 75.6%). Statistical analysis conducted using PASW ver. 18.0 for Windows. The difference on the distribution of independent variables related with teacher-supervised toothbrushing was verified with chi-square test. The results of this research could be summarized as follows: The children in the teacher-supervised toothbrushing community child center, the practice rate of toothbrushing was higher than the children in the non-supervised toothbrushing community child center (p<0.05). Teachers offered children one of snacks and drinks per day independently of teacher-supervised toothbrushing (p>0.05). Most of participated teachers accepted to be responsible for oral health of children (73.4%) and demanded that improve facilities for a toothbrushing in community child center (77.2%). In conclusion, this study suggests that a programme of daily teacher-supervised toothbrushing can be effectively targeted into community child center.

A Study on Industries's Leading at the Stock Market in Korea - Gradual Diffusion of Information and Cross-Asset Return Predictability- (산업의 주식시장 선행성에 관한 실증분석 - 자산간 수익률 예측 가능성 -)

  • Kim Jong-Kwon
    • Proceedings of the Safety Management and Science Conference
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    • 2004.11a
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    • pp.355-380
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    • 2004
  • I test the hypothesis that the gradual diffusion of information across asset markets leads to cross-asset return predictability in Korea. Using thirty-six industry portfolios and the broad market index as our test assets, I establish several key results. First, a number of industries such as semiconductor, electronics, metal, and petroleum lead the stock market by up to one month. In contrast, the market, which is widely followed, only leads a few industries. Importantly, an industry's ability to lead the market is correlated with its propensity to forecast various indicators of economic activity such as industrial production growth. Consistent with our hypothesis, these findings indicate that the market reacts with a delay to information in industry returns about its fundamentals because information diffuses only gradually across asset markets. Traditional theories of asset pricing assume that investors have unlimited information-processing capacity. However, this assumption does not hold for many traders, even the most sophisticated ones. Many economists recognize that investors are better characterized as being only boundedly rational(see Shiller(2000), Sims(2201)). Even from casual observation, few traders can pay attention to all sources of information much less understand their impact on the prices of assets that they trade. Indeed, a large literature in psychology documents the extent to which even attention is a precious cognitive resource(see, eg., Kahneman(1973), Nisbett and Ross(1980), Fiske and Taylor(1991)). A number of papers have explored the implications of limited information- processing capacity for asset prices. I will review this literature in Section II. For instance, Merton(1987) develops a static model of multiple stocks in which investors only have information about a limited number of stocks and only trade those that they have information about. Related models of limited market participation include brennan(1975) and Allen and Gale(1994). As a result, stocks that are less recognized by investors have a smaller investor base(neglected stocks) and trade at a greater discount because of limited risk sharing. More recently, Hong and Stein(1999) develop a dynamic model of a single asset in which information gradually diffuses across the investment public and investors are unable to perform the rational expectations trick of extracting information from prices. Hong and Stein(1999). My hypothesis is that the gradual diffusion of information across asset markets leads to cross-asset return predictability. This hypothesis relies on two key assumptions. The first is that valuable information that originates in one asset reaches investors in other markets only with a lag, i.e. news travels slowly across markets. The second assumption is that because of limited information-processing capacity, many (though not necessarily all) investors may not pay attention or be able to extract the information from the asset prices of markets that they do not participate in. These two assumptions taken together leads to cross-asset return predictability. My hypothesis would appear to be a very plausible one for a few reasons. To begin with, as pointed out by Merton(1987) and the subsequent literature on segmented markets and limited market participation, few investors trade all assets. Put another way, limited participation is a pervasive feature of financial markets. Indeed, even among equity money managers, there is specialization along industries such as sector or market timing funds. Some reasons for this limited market participation include tax, regulatory or liquidity constraints. More plausibly, investors have to specialize because they have their hands full trying to understand the markets that they do participate in

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