• Title/Summary/Keyword: spread factor

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A Study on Width Spread in 2-High Rolling of Rectangular Bars (각재의 냉간 2단 압연에 있어서의 폭 증가율에 관한 연구)

  • 윤상건;김동원;인정제
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.13 no.5
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    • pp.831-836
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    • 1989
  • It was found that the effect of the friction between the roll and the workpiece on the spread ratio in flat rolling processes varies with the width-to-height ratio and the reduction in height by Tozawa, Oh and kobayashi numerically. In the present study, the barrelling profile accompanying the width spread was predicted by using the energy method proposed by Kato, which is known to be one of the most advanced method for the three dimensional analysis of the rolling process. The modified velocity field was applied to compute the width spread and the result was verified by experiments. the analysis by the energy method gave the result that the spread ratio increases with the friction factor when the width-to-height ratio is 1 and decreases when the ratio is larger then 2, being consistent with the results of Tozawa and Oh. Nevertheless the cold rolling experiment for pure aluminium showed that the spread ratio decreases with the increasing friction factor irrespective of the width-to-hight ratio.

Quality Characteristics of Sugar Snap-Cookie Added to Carrot Powder (II) - Quality Characteristics of Sugar Snap-Cookie - (당근 분말을 첨가한 Sugar Snap-Cookie의 품질 특성에 관한 연구(2) - 쿠키의 품질 특성 -)

  • Hwang, Seung-Hwan
    • Journal of the East Asian Society of Dietary Life
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    • v.20 no.2
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    • pp.307-312
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    • 2010
  • Sugar snap cookies were prepared with the addition of carrot powder (2~12%) as a source of dietary fiber. Analyses of physiochemical properties, rheology and sensory evaluation of the cookies were conducted. Increasing carrot powder content weakened the flour, as evidenced by decreased diameter and increased thickness, which resulted in decreased spread factor. The water content of the carrot powder-amended cookies and unamended flour was not significantly different. The pH and L values progressively decreased and a and b values progressively increased with increasing addition of carrot powder. Textural analysis revealed no significant differences in brittleness with carrot powder addition, even though brittleness did decrease with the addition of more carrot powder. Sensory evaluation revealed a preference for cookies prepared with 2~4% carrot powder, with decreased preference at powder concentrations exceeding 6%. Addition of a dried vegetable with high fiber content caused the dietary fiber to absorb much water content, resulting in decreased diameter, increased thickness and decreased spread factor. Therefore, it is deemed desirable to increase the spread factor by controlling the water content and adding emulsifiers so as to enhance the functionality and maintain the quality of cookies.

MIMO Radio Channel Measurement and Analysis at 781MHz (781MHz 대역에서 MIMO 전파 채널 측정 및 분석)

  • Jeong, Won-Ho;Kim, Joo-Seok;Jung, Myoung-Won;Yoon, Young-Keun;Kim, Jong-Ho;Kim, Kyung-Seok
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.2
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    • pp.181-188
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    • 2012
  • In this paper, the measurement data is analyzed and channel parameters are derived through MIMO Channel measurements at 781MHz considering outdoor multi-path environment. 781MHz frequency band currently operates the DTV system. However, it will be allocated new mobile communication frequency band. The channel characteristics at 781MHz seem to be similar existing mobile communication system at 900MHz but a study on channel characteristics of signal transfer process is necessary because there is incomplete study in mobile networks at 781MHz. To avoid interference with Korean DTV broadcasting, we measured channel characteristics in city/suburban areas of Jeju island by channel sounder and $4{\times}4$ antenna of the ETRI(Korea Electronics and Telecommunications Research Institute). Path Loss, Delay Spread, Angular Spread and K-factor were derived based on measured data.

Myrrha Induces Enhanced Keratinocyte Growth Factor in Scald Burn Skin of Rat

  • Cho, Hyun-Gug;Lee, Hang-Woo;Kim, Jeong-Ki;Lee, Yong-Deok;Chung, Hyeung-Jae
    • Biomedical Science Letters
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    • v.7 no.3
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    • pp.139-143
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    • 2001
  • The present study was conducted to determine whether skin spread of Myrrha has an effect on the cell regeneration as well as wound healing following dermal scald burn injury, keratinocyte growth factor (KGF) level was analyzed immunologically in conjunction with the histological changes occurred in skin tissue. The KGF contents in Myrrha skin spread group, which shows cell regeneration ability in skin tissue after burn, increased after 5 hours. After 24 hours, 'the content of Myrrha skin spread group is noticeably higher than at 5 hours postburn. After 72 hours, KGF was decreased compared to at 24 hours postburn. Acceleration effect of KGF production in Myrrha skin spread group was high. Together with the result of histological changes, skin spread of Myrrha reduced protein degeneration and edema in dermis, and induced proliferation of epithelial cells. The data suggest that Myrrha has accelerate cell regeneration and wound healing in case of scald burn skin by spreading of paste.

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Aerodynamic Approaches for Estimation of Waste Disease Spread in Pig Farm through Airborne Contaminants (양돈장의 소모성질병 확산 분석을 위한 현장 모니터링 및 공기유동학적 분석)

  • Seo, Il-Hwan;Lee, In-Bok;Moon, Oun-Kyung;Kwon, Kyeong-Seok
    • Journal of The Korean Society of Agricultural Engineers
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    • v.56 no.1
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    • pp.41-49
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    • 2014
  • Pig chronic wasting disease, including porcine reproductive and respiratory syndrome (PRRS) and postweaning multisystemic wasting syndrome (PMWS), have made a continuous economic damage in pig farms. Airborne spread of livestock viruses are an important spread factor which is difficult to analyze due to invisible airflow and limitation of measurement. The objective of this study is to analyze airborne disease spread between buildings in the experimental pig farm by means of field experiment and computational fluid dynamics (CFD). The field experiments were conducted to capture airborne virus using air sampler and teflon filter along multi points in the experimental pig farm. The samples were tested in terms of virus detection resulting in positive reaction for PRRS and PCV-2 viruses, which can be a firm evidence of airborne virus spread. The CFD simulation model was developed by considering complex topography, wind conditions, building arrangement, and ventilation systems and was used to analyze airborne virus spread according to different wind conditions. The CFD computed result showed a possibility of airborne virus spread via livestock aerosol from infected pig house to neighboring pig houses according to wind directions. The CFD simulation technique is expected to provide significant data for estimating and making a counterplan against airborne disease spread.

A Novel Random PWM Technique with a Constant Switching Frequency Utilizing an Offset Voltage (옵셋 전압을 이용한 일정 스위칭 주파수의 Random PWM 기법)

  • Kim, Do-Kyeom;Kim, Sang-Hoon
    • The Transactions of the Korean Institute of Power Electronics
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    • v.22 no.1
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    • pp.67-74
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    • 2017
  • This study proposes a novel random pulse-width modulation (PWM) technique with a constant switching frequency utilizing a random offset voltage. The proposed PWM technique spreads switching harmonics by varying the position of an active voltage vector without a switching frequency variation. The implementation of the proposed PWM technique is simple because it does not require additional hardware and complex algorithm. The proposed random PWM technique is compared with the conventional PWM technique on the factors of harmonic spectrum, total harmonic distortion, and harmonic spread factor to confirm the harmonic spread effect. The validity of the proposed method is verified by simulations and experiments on a three-phase inverter drive system.

Quality Characteristics of Cookies Prepared with Ulleung-Maesil (Prunus mume fruit) Powder (울릉매실 분말 첨가 쿠키의 품질 특성)

  • Kim, Mi-Hyun;Lee, Jin-Sil
    • Journal of the Korean Home Economics Association
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    • v.48 no.2
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    • pp.113-120
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    • 2010
  • Quality characteristics effects of adding four different amounts (0%, 1%, 2%, 3%) of Ulleung-Maesil (Prunus mume fruit) powder cookie doughs were examined. pH, water content & bulk density of dough, spread factor, color value, hardness and consumer acceptability of maesil cookies were measured. The pH and water content of freezedried Ulleung-Maesil powder were 2.01 and 6.26%, respectively, while the L, a, b values were 76.14, -1.66 and 28.65, respectively. Although bulk density of the 3% powder group of cookie dough was the highest, its pH value was the lowest compared to the other groups (p < 0.05). Spread factor of the 3% group showed the lowest value among all groups (p < 0.05). Hardness of the control group (i.e, 0%) was significantly higher than the 1%, 2%, 3% groups (p < 0.05), which showed no significant difference among themselves. The ${\Delta}E$ value of cookies increased significantly with increasing Maesil powder content (p < 0.05). The consumer acceptability scores for control and 1% Maesil cookie groups ranked significantly higher than the 2% and 3% groups in overall acceptability, taste, flavor and texture (p < 0.05). In conclusion, our study suggests that small amounts of Ulleung-maesil can add positive attributes to cookies.

Physicochemical and Sensory Characteristics of Pumpkin Cookies Using Ginseng Powder (인삼을 첨가한 호박쿠키의 이화학적 및 관능적 특성)

  • Park, Ji-Hyun;Kim, Hae-Young
    • Korean journal of food and cookery science
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    • v.22 no.6 s.96
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    • pp.855-863
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    • 2006
  • The purpose of this study was to provide the basic information on the functional cookies with pumpkin and ginseng powder. Pumpkin cookies with ginseng powder were prepared at various additions adding (0 g, 3 g, 6 g, 9 g). With increasing As the addition of ginseng powder additionincreased, there were significant decrease in the water contents and crude protein were significantly decreased (p<0.05). The spread factor and Hunter color's L, a, and b values in th dough and cookies were significantly decreased with increasing as the addition level of ginseng powder content was increased(p<0.05). Hardness measured using rheometer and onset, peak, and closing temperatures and gelatinization enthalpy using DSC showed significantly the higher values with increasing more additions of ginseng powder content. In sensory evaluation, surface cracking, and pumpkin flavor were decreased with lower levels of ginseng powder. Ginseng flavor and hardness were increased with lower levels of ginseng powder Overall desirability of cookies with addition of 3 g added ginseng powder was the highest of the four samplesproduction. Surface crakcracking washadhighly positively correlated with spread factor, a (redness) (p<0.01)and but negatively correlated with carbohydrate content (p<0.05). Ginseng aroma showed negative correlation to the water contents, crude protein, spread factor, and Hunter's a (redness) and b (yellowness) values (p<0.05).

Effect of Broccoli Powder Incorporation on Physicochemical Properties of Cookies

  • Lee, Jun Ho;Lee, Hye Young;Sung, Chang Yong
    • Food Engineering Progress
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    • v.14 no.1
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    • pp.60-64
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    • 2010
  • Freeze-dried broccoli powder was incorporated into cookie dough at 5 levels (0, 1, 2, 3, and 4%, w/w) by replacing equivalent amount of wheat flour of the cookie dough. After aging and sheeting, cookies were baked at 170${^{\circ}C}$ for 8 min in an oven. The baked cookies were cooled to room temperature for 1 hr and packed in airtight bags prior to all measurements. The pH and moisture content were ranged 6.74-6.90 and 2.67-4.12% (wet basis) depending on the broccoli powder level, respectively. Lightness (L$^{\ast}$-value), redness (a$^{\ast}$-value), and hardness decreased while yellowness (b$^{\ast}$-value) increased significantly as the broccoli powder content increased (p<0.05). Spread factor of the control was significantly lower than that of samples containing broccoli powder regardless of the concentration (p<0.05) and increased significantly with increase in broccoli powder content (p<0.05). The broccoli concentration correlated significantly with most of properties except for pH and spread factor (p<0.05 or p<0.01). Hardness correlated negatively with moisture content (p<0.05) but correlated positively with spread factor (p<0.01).

A Study on the Progress of e-Trade and the Factor of the Adoption of bolero.net in Japan

  • Naganuma, Ken;Lee, Young-Chan
    • International Commerce and Information Review
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    • v.6 no.3
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    • pp.123-136
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    • 2004
  • In recent years, although far behind, the "e-Trade (B to G)" is propelled vigorously in Japan. But the diffusion of the "e-Trade" among companies (B to B) represented by bolero.net does not meet expectation. This paper carried out the questionnaire survey to the enterprises, which adopt bolero.net and examined why the diffusion is stagnated to the measures for its future spread. As a result, the top 3 adoption factors are: (1) Transaction climate, (2) Top management support, and (3) Operational improvement. In other words, it depends that top management has the will, which adopts e-trade positively among the reliable business partners and the operational performances can improve efficiently by carrying e-trade. We would like to clarify what will be crucial to spur the diffusion in the future. Based on the findings from the result, the concrete key points to promote the spread are to be indicated as follows: (1) Improve the scores of "Cost" and "Competitive pressure" (2) Improve the institutional factor.

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