• Title/Summary/Keyword: Ambient Control

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Reduction of magnetic anomaly observations from helicopter surveys at varying elevations (고도가 변화하는 헬리콥터 탐사에서 얻어지는 자력이상의 변환)

  • Nakatsuka, Tadashi;Okuma, Shigeo
    • Geophysics and Geophysical Exploration
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    • v.9 no.1
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    • pp.121-128
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    • 2006
  • Magnetic survey flights by helicopters are usually parallel to the topographic surface, with a nominal clearance, but especially in high-resolution surveys the altitudes at which observations are made may be too variable to be regarded as a smooth surface. We have developed a reduction procedure for such data using the method of equivalent sources, where surrounding sources are included to control edge effects, and data from points distributed randomly in three dimensions are directly modelled. Although the problem is generally underdetermined, the method of conjugate gradients can be used to find a minimum-norm solution. There is freedom to select the harmonic function that relates the magnetic anomaly with the source. When the upward continuation function operator is selected, the equivalent source is the magnetic anomaly itself. If we select as source a distribution of magnetic dipoles in the direction of the ambient magnetic field, we can easily derive reduction-to-pole anomalies by rotating the direction of the magnetic dipoles to vertical.

Respiratory Characteristics and Quality Attributes of Mature-Green Mume (Prunus mume Sieb. et Zucc) Fruits as Influenced by MAP Conditions (포장조건에 따른 청매실의 호흡생리 및 선도유지 특성)

  • Chan, Hwan-Soo;Hong, Seok-In;Park, Jung-Sun;Park, Yong-Kon;Kim, Kwan;Jo, Jae-Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.28 no.6
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    • pp.1304-1309
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    • 1999
  • The respiratory characteristics and quality attributes of mature green mume fruits as influenced by modified atmosphere packaging(MAP) conditions during storage at 25oC for 8 days were investigated. The quality attributes of mume fruits were evaluated in terms of fresh weight loss, physiological injury and yellowing. The packaging materials used for MAP were low density polyethylene(LDPE) films with various different thicknesses. Yellowing and fresh weight loss of mume fruits were noticeably reduced by the packaging treatments with LDPE A and B. The physiological injury of the fruits during storage was found to be more severe in LDPE C than others. For LDPE A and B, the oxygen and carbon dioxide contents within the packages of Mume fruits maintained at the levels of 2~3% and 7~8%, respectively. With respect to visual quality, MAP prolonged the shelf life of the fruits much longer compared with the unsealed control. From the experimental results, it is suggested that the LDPE films with the gas trans mission rates of about 2,100 O2 ml/m2.day.atm and 6,700 CO2 ml/m2.day.atm would be proper for MAP of mature green mume fruits during storage at ambient temperature.

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Effect of Soluble Starch Pretreatment and Storage Condition on Caking Degree and Moisture Sorption of Powdered Onion (가용성 전분의 전처리와 저장조건이 분말양파의 Caking과 수분흡수에 미치는 효과)

  • 김명환
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.20 no.3
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    • pp.272-275
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    • 1991
  • The effects of storage temperature and relative humidity (RH), and immersion treatment (30min) of sliced onions in various soluble starch solutions(1-3%; w/v) at $25^{\circ}C$ before air dehydration on caking and water absorption degree of powedered onion were analyzed. In the range of 15 to $35^{\circ}C$, the caking tendency of powdered onion increased with temperature at a constant RH (70% RH). The caking degree of powdered onion also increased as increasing the storage RH, at $25^{\circ}C$. Storage starchpreteatment significantly reduced the water absorption and caking degree of powdered onion under ambient condition. A pretreatment of soluble starch solution(3%) reduced almost 80% the caking of powdered onion compared to that of control.

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Ecophysiological responses of Quercus gilva, endangered species and Q. glauca to long-term exposure to elevated CO2 concentration and temperature

  • Kim, Hae-Ran;You, Young-Han
    • Journal of Ecology and Environment
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    • v.35 no.3
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    • pp.203-212
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    • 2012
  • The physiological effects of elevated $CO_2$ concentration and temperature were examined for Quercus gilva and Q. glauca grown under control (ambient $CO_2$ and temperature) and treatment (elevated $CO_2$ and temperature) conditions for 39 months. The objective of the study was to measure the long-term responses, in physiological parameters, of two oaks species exposed to elevated $CO_2$ and temperature. The photosynthetic rate of Q. gilva was found to be decreased, but that of Q. glauca was not significantly affected, after long-term exposure to elevated $CO_2$ and temperature. Stomatal conductance of Q. glauca was reduced by 21.7%, but that of Q. gilva was not significantly affected, by long-term exposure to $CO_2$ and temperature. However, the transpiration rate of the two oak species decreased. Water use efficiency of Q. gilva was not significantly affected by elevated $CO_2$ and temperature, while that of Q. glauca was increased by 56.6%. The leaves of Q. gilva grown under treatment conditions had an increased C:N ratio due to their reduced nitrogen content, while those of Q. glauca were not significantly affected by long-term exposure to elevated $CO_2$ and temperature. These results suggest that the long-term responses to elevated $CO_2$ and temperature between Q. gilva and Q. glauca are different, and that Q. gilva, the endangered species, is more sensitive to elevated $CO_2$ and temperature than Q. glauca.

Dynamic PIV Measurements of Wake behind a Rotationally Oscillating Circular Cylinder (주기적으로 회전진동하는 원주 후류의 Dynamic PIV 속도장 측정)

  • Lee, Jung-Yeop;Lee, Sang-Joon
    • 한국가시화정보학회:학술대회논문집
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    • 2007.11a
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    • pp.134-137
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    • 2007
  • The temporal evolution of wake behind a circular cylinder oscillating rotationally with a relatively high forcing frequency has been investigated experimentally using a dynamic PIV technique. Experiments were carried out with varying the frequency ratio $F_R\;(=f_f/f_n)$ in the range from 0.0 (stationary) to 1.6 at oscillation amplitude of ${\theta}_A=30^{\circ}$ and Reynolds number of $Re=4.14{\times}10^3$. Depending on the forcing condition ($F_R$), the flow was divided into three regimes; non-lock-on ($F_R=0.4$), transition ($F_R=0.8$, 1.6) and lock-on regimes ($F_R=1.0$) with markedly different flow structure in the near-wake region behind the cylinder. When the frequency ratio was less than 1.0 ($F_R{\le}1.0$), the rotational oscillatory motion of the cylinder decreased the length of the vortex formation region and enhanced the mutual interaction between large-scale vortices across the wake centerline. The entrainment of ambient fluid seemed to play an important role in controlling the near-wake flow and shear-layer instability. However, the flow characteristics changed markedly beyond the lock-on flow regime ($F_R=1.0$) due to high-frequency forcing. At $F_R=1.6$, the mutual interactions between the vortices shed from both sides of the cylinder were not so strong. Thereby, the flow entrainment and momentum transfer into the wake center region were reduced. In addition, the size of the large-scale vortices decreased since the lateral extent of the wake was suppressed.

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Impact of Seasonal Conditions on Quality and Pathogens Content of Milk in Friesian Cows

  • Zeinhom, Mohamed M.A.;Abdel Aziz, Rabie L.;Mohammed, Asmaa N.;Bernabucci, Umberto
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.8
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    • pp.1207-1213
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    • 2016
  • Heat stress negatively affects milk quality altering its nutritive value and cheese making properties. This study aimed at assessing the impact of seasonal microclimatic conditions on milk quality of Friesian cows. The study was carried out in a dairy farm from June 2013 to May 2014 at Beni-Suef province, Egypt. Inside the barn daily ambient temperature and relative humidity were recorded and used to calculate the daily maximum temperature-humidity index (mxTHI), which was used as indicator of the degree of heat stress. The study was carried out in three periods according to the temperature-humidity index (THI) recorded: from June 2013 to September 2013 (mxTHI>78), from October 2013 to November 2013 (mxTHI 72-78) and from December 2013 to April 2014 (mxTHI<72). Eighty Friesian lactating dairy cows were monitored in each period. The three groups of cows were balanced for days in milk and parity. Milk quality data referred to somatic cell count, total coliform count (TCC), faecal coliform count (FCC), Escherichia coli count, percentage of E. coli, and Staphylococcus aureus, percentage of fat, protein, lactose, total solid and solid non-fat. Increasing THI was associated with a significant decrease in all milk main components. An increase of TCC, FCC, and E. coli count from mxTHI<72 to mxTHI>78 was observed. In addition, the isolation rate of both S. aureus and E. coli increased when the mxTHI increased. The results of this study show the seriousness of the negative effects of hot conditions on milk composition and mammary gland pathogens. These facts warrant the importance of adopting mitigation strategies to alleviate negative consequences of heat stress in dairy cows and for limiting related economic losses.

Characteristics of Thermal Performance on the Different Ambient Air Temperatures of Green Roof Plants

  • Han, Seung Won;Park, Joon Sung;Kim, Jae Soon;Jeong, Myung Il
    • Korean Journal of Environmental Biology
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    • v.34 no.4
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    • pp.272-280
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    • 2016
  • Changes in land use and increase in urban energy consumption influence urban life. This study analyzed the characteristics and patterns of urban heat and presents management schemes to generate a comfortable and sustainable urban environment. The study aimed to demonstrate the positive effects of artificial ground greening on improving the microclimate through evapotranspiration using perennial herbs. We have designed a chamber that could control constant temperature and humidity, measure temperature reductions in each plant and changes in sensible heat and latent heat. This study identified Sedum kamtschaticum as the most effective plant in controlling temperature. At $22^{\circ}C$, $3.2^{\circ}C$ temperature reduction was observed, whereas four other plants showed a $1.5^{\circ}C$ reduction. At $25^{\circ}C$, $2.0^{\circ}C$ temperature reduction was observed. On the other hand, the use of Sedum sarmentosum resulted in the lowest effect. Zoysia japonica is the most commonly used ground covering plant, although the temperature reduction of Lysimachia nummularia was more effective at high temperature conditions. Sensible heat and latent heat were calculated to evaluate the thermal performance of energy. At a temperature >$30^{\circ}C$, L. nummularia and S. sarmentosum emitted high latent heat. In this study, we analyzed the thermal performance of green roof perennial plants; in particular, we analyzed the evapotranspiration and temperature reduction of each plant. Since the substrate depth and types, plant species, and seasonal change may influence temperature reduction and latent heat of green roofs, further studies are necessary.

Evaluation of the Head Mouse System using Gyro-and Opto-Sensors (각속도 및 광센서를 이용한 헤드 마우스의 평가)

  • Park, Min-Je;Kim, Soo-Chan
    • Journal of the HCI Society of Korea
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    • v.5 no.2
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    • pp.1-6
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    • 2010
  • In this research, we designed the head mouse system for disabled and gamers, a mouse controller which can be controlled by head movements and eye blinks only, and compared its performance with other regular mouse controller systems. The head mouse was moved by a gyro-sensor, which can measure an angular rotation of a head movement, and the eye blink was used as a clicking event of the mouse system. Accumulated errors caused by integral, which was a problem that previous head mouse system had, were removed periodically, and treated as dead zones in the non-linear relative point graph, and direct mouse point control was possible using its moving distance and acceleration calculation. We used the active light sources to minimize the influence of the ambient light changes, so that the head mouse was not affected by the change in external light source. In a comparison between the head mouse and the gazing tracking mouse (Quick Glance), the above method resulted about 21% higher score on the clicking event experiment called "20 clicks", about 25% higher on the dasher experiment, and about 37% higher on on-screen keyboard test respectively, which concludes that the proposed head mouse has better performance than the standard mouse system.

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Effect of Supplementing Grazing Cattle Calves with Urea-molasses Blocks, with and without Yucca schidigera Extract, on Performance and Carcass Traits

  • Mirza, I.H.;Khan, A.G.;Azim, A.;Mirza, M.A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.9
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    • pp.1300-1306
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    • 2002
  • Fourteen non-descript zebu cattle calves of about 1 year and 6 months age and 111 kg average body weight were used in this experiment. Grazing (5 h daily) animals were supplemented with urea-molasses blocks with and without Yucca, while the control group was without any supplementation i.e. grazing only. The feeding trial continued for a period of 70 days (November to February). At the end of trial three animals per treatment were slaughtered to compare carcass traits. Group no. 1 was fed block with yucca, group no. 2 was fed block without yucca and group no. 3 was on grazing only. Block intake was found to be 724 g/h/d and 1,239 g/h/d for group no. 1 and group no. 2, respectively (p<0.05). Feed efficiency of blocks was found to be 2.71 kg and 4.86 kg for group no. 1 and group no. 2, respectively (p<0.05). Block intake per kg $BW^{0.75}$ was found to be 14.75 and 26.05 gram for group 1 and group 2, respectively (p<0.05). Average daily body weight gain was found to be 267 g/h/d, 255 g/h/d and 169 g/h/d for group 1, 2 and 3, respectively. Carcass traits among the three treatments were found to be statistically similar. Thus urea-molasses blocks supplementation improved body weight gain and addition of yucca in the blocks further improved body weight gain, feed efficiency and economics. Environment (ambient temperature, rainfall, wind and humidity) had no significant effect on three treatments.

A Usability Study On Museum Installations Emphasizing Interaction Design for User Experience (사용자 경험 증진을 위한 과학관 전시물의 사용성 평가)

  • Cho, Myung Eun;Choi, Han Hee;Kim, Mi Jeong
    • Korean Institute of Interior Design Journal
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    • v.22 no.5
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    • pp.302-310
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    • 2013
  • Many museums have recently employed digital technologies in exhibition installations to provide visitors with interactive experiences with the installations, not just audiences. However, most of them have focused on the adoption of new prototypes or technologies, not considering user experiences of those systems carefully. This study developed an evaluation tool for usability of the tangible user interfaces and conducted a usability study on museum installations emphasizing user interaction and experience. The evaluation tool is composed of 5 features of tangible user interfaces such as tangible, interaction, convenience, representation, spatial interaction and social interaction, and 24 items. The museum we investigated is the Gwacheon National Science Museum, where 8 installations, classified 4 categories, were selected for the usability study. We recruited 6 undergraduate students, who were divided into 2 teams, each team having 3 students. Three students in a team manipulated and experience each installation together and reported their evaluation score through the questionnaire and interviews. The results showed that the score of the usability for the category 3, which requires students to move their bodies for the interaction, is the highest one because it features with spatial interaction. Students expressed much interest in the category 4, which utilizes users' other senses, however, the score of the usability is the lowest because the interaction is temporary and repetitive. Most installations are well designed in terms of control constraints, legibility, lower thresholds, participation encouragement, and open to the public, but pooly designed in terms of multiple access points, configurability, accurate movement, ambient media, and full-body interaction.