• Title/Summary/Keyword: falling number

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Effect of Commercial Multi-Emulsifiers on Rheological Properties of Cake Flour (상업용 복합유화제가 박력분의 물성에 미치는 영향)

  • Bok, Jin-Hung;Hwang, Sung-Yeon;Lee, Jeong-Hoon
    • Culinary science and hospitality research
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    • v.13 no.3
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    • pp.158-165
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    • 2007
  • This study was carried out to evaluate the rheological properties of cake flour with 3% of commercial multi-emulsifiers(P company, W company, O company) based on flour. Rheological properties were analyzed by Falling number, RVA, Alveograph and Farinograph. In Falling number, viscosity of cake flour with multi-emulsifiers was increased. In RVA, initial pasting temperature was increased by adding multi-emulsifier except for W company. and peak viscosity, final viscosity and setback were increased but breakdown was decreased. In Alveogram, P and P/L value were decreased but L and G value were increased. In Farinogram, water absorption was decreased but dough development time was increased and stability was increased except for P company.

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Effect of Wavy Flow of Vertical Falling Film on the Absorption Performance (흡수성능에 미치는 수직 액막 파동의 영향에 관한 연구)

  • 김정국;조금남
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.2
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    • pp.194-201
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    • 2004
  • In the present study, the improvement of absorption characteristics on combined heat and mass transfer process in a falling film of a vertical absorber by change of geometric parameters were studied experimentally and analytically. The energy and diffusion equations are solved simultaneously to give the temperature and concentration variations at the liquid solution-refrigerant vapor interface and at the wall. Absorption behaviors of heat and mass transfer were analyzed through falling film of the LiBr aqueous solution contacted by refrigerant vapor in the absorber. Effects of film Reynolds number, geometric parameters by insert device (spring) and flow pattern on heat and mass transfer performances have been also investigated. Especially, effects of the flow pattern by geometric parameters have been considered to observe the total heat and mass transfer rates through falling film along the absorber. As a numerical and experimental result, maximum absorption rate was shown at the wave-flow by insert device (spring). The error ranges between experiment and analysis were from 5.8 to 12% at Re$_{f}$ > 100.0.

Numerical study on motion characteristics of a free falling two-dimensional circular cylinder in a channel using an Immersed Boundary - Lattice Boltzmann Method (가상경계 격자 볼츠만 법을 이용한 채널 내 자유 낙하하는 2차원 원형 실린더의 운동 특성)

  • Jeong, Hae-Kwon;Ha, Man-Yeong;Yoon, Hyun-Sik;Kim, Sung-Jool
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2489-2494
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    • 2008
  • The two-dimensional circular cylinder freely falling in a channel has been simulated by using Immersed boundary - lattice Boltzmann method in order to analyze the characteristics of motion originated by the interaction between the fluid and the solid. The wide range of the solid/fluid density ratio has been considered to identify the effect of the solid/fluid density ratio on the motion characteristics such as the falling time, the terminal velocity and the trajectory in the vertical and horizontal directions. In addition, the effect of the gap between the cylinder and the wall on the motion of two-dimensional circular cylinder freely falling has been revealed by taking into account a various range of the gap size. The Reynolds number in terms of the terminal velocity is diminished as the cylinder becomes close to the wall at the initial dropping position, since the repulsive force induced between the cylinder and wall constrains the vertical motion. Quantitative information about the flow variables such as the pressure coefficient and vorticity on the cylinders is highlighted.

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Influence of Spring on The Absorption Performance of a Vertical Absorber Tube (수직 흡수전열관의 흡수성능에 미치는 스프링의 영향)

  • 김정국;조금남
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.14 no.10
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    • pp.825-832
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    • 2002
  • The present study investigated the enhancement of the absorption performance by the spring wrapped around the outer surface of the vertical falling film absorber tube. Heat and mass transfer enhancements were experimentally investigated, and flow visualization was performed to observe the wettability and flow pattern of the solution. The key experimental parameters were spring diameter (0.5, 1.0 mm) and spring pitch (1, 3, 10 mm), film Reynolds number (50~150), and concentration of LiBr-$H_2O$ solution (55, 60, 65 wt%). As the spring diameter was increased, the absorption mass flux, Sherwood number, Nusselt number, heat flux, and heat transfer coefficient were increased The Nusselt and Sherwood numbers showed the maximum at the spring pitch of 3mm, and the ratio of pitch to diameter of approximately 3 and 6 for the spring diamter of 0.5 mm, respectively.

Factors Influencing the Fear of Falling in Elderly in Rural Communities (일부농촌지역 재가 낙상경험노인의 낙상두려움 관련요인)

  • Lee, Sang-Gon;Kim, Hyo-Jung
    • Journal of agricultural medicine and community health
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    • v.36 no.4
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    • pp.251-263
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    • 2011
  • Objectives: The purpose of this study was to examine the factors associated with fear of falling among the elderly dwelling in rural communities. Methods: From February 1, 2010 to March 31, 2010, a questionnaire-based survey was sent to 2,628 persons 65 years or older dwelling in 1 Myeon and 1 Eup of Gyeongsangnam-do. Among these participants, 735 (27.9%) had fallen more than once in 2009. For data analysis, descriptive statistics and hierarchical multiple regression were performed using SPSS version 12.0. Results: Factors influencing the fear of falling in the elderly according to falls experienced were number of outpatient visits, number of falls, gender, admission, purchasing of health function foods, and activities of daily living. Overall, the study showed significant differences in the score of fear of falling according to gender, age, education, marital status, living arrangement, main means of mobilization, drinking, income, number of falls, admission, number of outpatient visits, experience with outpatient oriental medicine, purchasing of health function foods, medical assistance devices, season, fall location, fall cause, shoe type, injury type, limitation of activity, and activities of daily living. Conclusions: The results of this study suggest that programs should be developed specifically for elderly people who have experienced more than one fall because of increased fear due to multiple falls.

Rheological Characteristics of Flour Batters in the Presence of Mugwort Powder (쑥 분말을 첨가한 소맥분의 리올로지 특성에 관한 연구)

  • Lee, Hyun-Ja;Park, Sang-Hae;Kang, Kun-Og
    • The Korean Journal of Community Living Science
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    • v.20 no.2
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    • pp.231-237
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    • 2009
  • This study was conducted to investigate the effects of mugwort powder on two types of flour batters, i.e., medium and cake, using the Falling Number test, RVA test, alveogram, and farimogram. The mugwort powder was added at 3% and 5% on the medium and cake flour bases, respectively. The Falling Numbers of the medium and cake flour batters with mugwort powder were increased due to the alteration of the protein in the flour. Analysis of the RVA characteristics showed that the addition of mugwort powder did not have significant effects on the initial pasting temperature. Peak viscosity, holding strength, final viscosity, and set back values of the medium flour batter were not consistent, but those of the cake flour batter were decreased. The characteristics of the alveogram showed that the addition of mugwort powder increased the extensibility and the swelling index. Farinogram demonstrated that the addition of mugwort powder decreased the water absorption and improved the stability of the medium and cake flour batters.

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Experimental Study on Downstream Local Scour of Free-Falling Jet (자유낙하수맥 하류부에서의 세굴에 관한 실험적 연구)

  • 윤세의;이종태
    • Water for future
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    • v.28 no.4
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    • pp.147-154
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    • 1995
  • Scour characteristics of noncohesive bed materials at the downstream of free-falling jet were analyzed through hydraulic experiments. It was assumed that the downstream had no special energy dissipators. Flow characteristics of free falling jet from rectangular section were studied, and scour characteristics with and without mounds, which were generated at the downstream of the scour hole, were comparatively analyzed for various bed materials, discharges and tailwater depths. Not only the equilibrium scour depth but also the height of mound could be expressed as a function of densimetric Froude number. Densimetric Froude number had closer relationship with the equilibrium dimensionless scour depth than other dimensionless parameters. It was suggested that the mound effects should be considered at the design stage of bed protection works.

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Fear of Falling, Falls Efficacy and Fall Prevention Behaviors according to the Fall Experience among Older Adults in Outpatient Settings (외래방문 노인의 낙상경험 유무에 따른 낙상에 대한 두려움, 효능감 및 예방행위)

  • Uhm, In Ae;Hwang, Seon Young
    • Journal of East-West Nursing Research
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    • v.27 no.1
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    • pp.61-69
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    • 2021
  • Purpose: This study aims to determine the association between fear of falling, falls efficacy, and fall prevention behaviors in older adults in outpatient and identify the factors affecting fall prevention behaviors. Methods: This was a descriptive study. A total of 137 older adults aged 60 or older with more than one disease in an outpatients setting were recruited from a university hospital in Seoul. Data were collected from March 11 through April 8, 2016. Results: The experience of a fall was significantly associated with age (t=-2.71, p=.008), gender (𝛘2=14.32, p<.001), education (𝛘2=6.05, p=.049), income (𝛘2=9.93, p=.019), physical activity status (𝛘2=16.84, p<.001), and the number of diseases (t=-2.89, p=.004). Fall experience was not significantly associated with marital status (𝛘2=3.79, p=.285). Multiple regression analysis revealed that the most influential factor of fall prevention behaviors was the fear of falls (β=-.37, p<.001), followed by the number of diseases (β=-.20, p=.013). Conclusion: It is necessary to provide preventive fall education with older adults in outpatients settings considering the fear level of falling and the numbers of accompanying diseases.

Evaluation of Balance Capability in Facilities Maintenance Workers using Screening Tools (스크리닝 도구를 이용한 건물관리업 종사자의 균형감각능력 평가)

  • Choi, Hyung Jin;Kim, Jung Soo
    • Journal of the Korea Safety Management & Science
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    • v.16 no.3
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    • pp.81-88
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    • 2014
  • A number of screening tools have been developed to evaluate the human balance capability. Many of them were designed to identify the elderly with falling risk. Three different screening tools, which have been well used many clinical fields, were used in this study. The purpose of this study was to evaluate balance capability in facilities maintenance workers in korea. There were no statistical significance between male and female when evaluated with three different screening tools. However, significant differences were found among the age groups irrespective of gender when evaluated with three different screening tools. The results of three different screening tools in korea showed poor values compared with previous results. These results revealed that facilities maintenance workers faced more critical falling risk in korea.

Heat Transfer Enhancement Characteristics for Falling-Film Evaporation on Horizontal Enhanced Tubes with Aqueous LiBr Solution (LiBr 수용액을 이용한 수평관 유하액막 증발의 촉진관 전열향상 특성)

  • Kim, Dong Kwan;Kim, Moo Hwan
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.9
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    • pp.1267-1276
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    • 1998
  • Falling-film evaporation experiments with aqueous lithium bromide (LiBr) solution were performed to investigate the heat transfer characteristics of enhanced copper tubes. Enhanced tubes (a knurled tube, a spirally grooved tube, and a tube coated with $20{\mu}m$ aluminum particles) and a bare tube were selected as test specimens. Averaged evaporation fluxes of water were obtained from horizontal tubes with various film Reynolds numbers, system pressures, LiBr concentrations and degrees of wall superheat. The enhanced performance of steam generation was compared between tubes with varying parameters. The knurled tube geometry showed the most excellent performance among the tubes tested. The specified enhanced tubes were more useful for generating steam on a low grade heat source such as waste heat.