• 한국작물학회지
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• 제49권3호
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• pp.155-159
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• 2004

This experiment was carried out to evaluate the microclimate of wheat canopy, growth and yield characteristics of wheat under north-south and east-west row orientation. The variety used in this experiment was "AG South 2000", which was developed in USA. Solar radiation, air temperature, relative humidity, and soil temperature were monitored by data logger from March to May in 2002, The ratio of light penetration to the bottom from the upper canopy was 36.8% in north-south and 21.4% in east-west row orientation. Temporal march of light penetration to the bottom from March to May decreased as wheat developed canopy structure and decreased a little from May as plant were matured. The highest light penetration to the bottom from upper canopy occurred at 13：00 in both north-south and east-west row orientations, respectively which were 36 times in north-south and 27 times in east-west row orientation, respectively. Daily maximum temperature at the bottom of canopy occurred at 14：00 with 29 times in north-south, while 19 times were obtained at 14：00 and 15：00, respectively in east-west row orientation. Relative humidity at the bottom of the canopy in east-west yow orientation showed higher than that of north-south row orientation. Occurrence of daily maximum soil temperature of north-south showed one hour later compared with east-west yow orientation. 1000 grain weight and test weight of north-south row orientation was higher than those of east-west vow orientation. Correlation coefficient between solar radiation of upper canopy and 1000 grain weight showed r=$0.8132^{*}$, and between air temperature of upper canopy and number of spikes per $\textrm{m}^{2}$ and 1000 grain weight showed significant positive correlation with r=$0.8139^{*}$, and r=$0.8293^{*}$, respectively.

• Journal of Mechanical Science and Technology
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• 제16권9호
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• pp.1137-1146
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• 2002

An experiment has been conducted on the flow and heat transfer characteristics of film coolant injected from a row of five holes with compound angle orientations of 35$^{\circ}$ inclination angle and 45$^{\circ}$ orientation angle. The Reynolds number based on the mainstream velocity and injection hole diameter 3.58${\times}$10$^4$. Three-dimensional velocity, film cooling effectiveness and heat transfer coefficient data are presented at three different mass flux ratios of 0.5, 1.0 and 2.0. Flow entrainment has been found between the vortices generated by adjacent injectants. The injectant with compound angle orientation entrains not only the mainstream boundary layer flow but also the adjacent injectant. Because of the flow entrainment, the injectant. With compound angle orientation is characterized by a single vortex while two bound vortices are usually observed in the case of simple angle injection. The strength of the secondary flow depends strongly on the mass flux ratio, which shows significant influence on the film cooling effectiveness and heat transfer coefficient.

• 대한기계학회논문집B
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• 제25권8호
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• pp.1122-1130
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• 2001

Film cooling performance from two rows of holes with opposite orientation angles is evaluated in terms of heat flux ratio. The film cooling hole has a fixed inclination angle of 35°and orientation angle of 45°for the downstream row and -45°for the upstream row. Four film cooling hole arrangements including inline and staggered configurations are investigated. The blowing ratio studied was 1.0. Boundary layer temperature distributions are measured to investigate injectant behaviors and mixing characteristics. Detailed distributions of the adiabatic film cooling effectiveness and the heat transfer coefficient are measured using TLC(Thermochromic Liquid Crystal). For the inline configuration, there forms a downwash flow at the downstream hole exit to make the injectant well attach to the wall, which gives high adiabatic film cooling effectiveness and heat transfer coefficient. The evaluation of heat flux ratio shows that the inline configuration gives better film cooling performance with the help of the downwash flow at the downstream hole exits.

• 대한기계학회논문집B
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• 제25권8호
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• pp.1131-1139
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• 2001

Experimental results are presented, which describe the effect of blowing ratio on film cooling from two rows of holes with opposite orientation angles. The inclination angle is fixed at 35°, and the orientation angles are set to be 45°for the downstream row, and -45°for the upstream row. The studied blowing ratios are 0.5, 1.0 and 2.0. The boundary layer temperature distributions are measured using thermocouple at two downstream locations. Detailed adiabatic film cooling effectiveness and heat transfer coefficient distributions are measured with TLC(Thermochromic Liquid Crystal). The adiabatic film cooling effectiveness and heat transfer coefficient distributions are discussed in connection with the injectant behaviors inferred from the boundary layer temperature distributions. Film cooling performance, represented by heat flux is evaluated from the adiabatic film cooling effectiveness and heat transfer coefficient data. The results show that the investigated geometry provides improved film cooling performance at the high blowing ratios of 1.0 and 2.0.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.113-118
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• 2000

Experimental results describing the effects of blowing ratio on film cooling from two rows of holes with opposite orientation angles are presented. The inclination angle was fixed at $35^{\circ}$ and the orientation angles were set to be $45^{\circ}$ for downstream row. and $-45^{\circ}$ for upsream row. The studied blowing ratios were 0.5, 1.0 and 2.0. The boundary layer temperature distributions were measured using thermocouple at two downstream loundary layer temperature distributions were measured using thermocouple at two downstream locations. Detailed adiabatic film cooling effectiveness and heat transfer coefficient distributions were measured with TLC(Thermochromic Liquid Crystal). The adiabatic film cooling effectiveness and heat transfer coefficient distributions are discussed in connection with the injectant behaviors inferred from the boundary layer temperature distributions. Film cooling performance, represented by heat flux was calculated with the adiabatic film cooling effectiveness and heat transfer coefficient data.

• 한국농촌건축학회논문집
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• 제15권2호
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• pp.25-32
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• 2013

The purpose of this study is to analyze the residential space composition and extension of Jeonja-jip and Dureong-jip in Samcheok region. The results of this study are as follows. It appears three residential plan types - Jeonja-jip with Anmaru(a room made of wooden floor), Jeonja-jip without Anmaru and Dureong-jip with Anmaru- in survey region. It was needed the extension of residential space at Jeonja-jip(a house type with two-row rooms which be composed of 田type under one roof) and Dureong-jip(a house type with inner floor which be surrounded by rooms under one roof) because of shortage of sleeping space, working space and keeping space owing to growing large family. The solutions of these shortages will be the extension of space in houses. Jeonja-jip's basic type which is the Kyup-Jip(a house type with two-row rooms under one roof) of 一 type with 6 Kans(Kan, a unit to count room to divided with four posts) is transformed and extended to 田shaped house with 11 Kans toward X-axis orientation. Dureong-Jip's basic type which is ㄱ type with 7 Kans is transformed and extended to the Sekyup-Jip with 9 Kans and the Nekyup-Jip(a house type with four-row rooms under one roof) with 12 Kans toward Y-axis orientation by insertion and addition. Jeonja-jip was developed into Kyup-Jip with front 4 or 5 Kans and side 2 Kans instead of being done into Sekyup-jip or Nekyup-Jip with insufficient day lighting and ventilation problems. Jeonja-jip and Dureong-jip were stronger than any other traditional houses in tendency to reserve Magu(cowshed) and Chikkan(toilet) in a house.

• Journal of Biosystems Engineering
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• 제10권1호
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• pp.13-23
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• 1985

Spraying method from the paddy-field levee is known to give insufficient penetration of the spray droplets to the rice stem of the densely grown plants, which is generally encountered at the last stage of rice growth. This study was intended to investigate the spraying system to solve this existing problem. As an approach, it was attempted to develop the boom-with-nozzle, between-the-row application system. Several types of nozzles and their different arrangements in the boom were tested in the field to measure the penetration-reaching distance and the uniformity of spray droplet distribution. The results of the study are summarized as follows: 1. Field experiments by the spraying method from the paddy-field levee showed to have practically no penetration of the spray droplets to the portion of the plant stem with the normal flow volume generally applied and thus need for improving present spraying method. 2. It was found that, considering both the uniformity of the spray droplet distribution and performance rate, the most efficient type of nozzle in the between-the-row boom-type spraying system was one that has core-insert hollow-cone with some clearance between the cone and tip. 3. When tested by applying the spraying method of between-the-row, the nozzle pressure did not affect the uniformity of spray droplet distribution. However, the nozzle pressure had a positive effect on the penetrating-reaching distance of the facing side of the rice stem and did not affect much on that of the opposite face of the stem. It was also found that the maximum pressure to affect the penetration-reaching distance was about $10kg/cm^2$. 4. The uniformity of the spray droplet distribution in the between-the-row system was greatly affected by the height and orientation of the nozzles in the boom. Based on experimental work for the different type of the boom-with-nozzle arrangements, it is recommended that the position of nozzle is set at about 0.45 m above the ground and two nozzles in the boom are oriented to be faced with each other with some angle such that the droplet stream from the nozzle would not directly face with each other.

• Bulletin of the Korean Chemical Society
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• 제30권8호
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• pp.1755-1759
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• 2009

Surface structure and molecular orientation of self-assembled monolayers (SAMs) formed by the spontaneous adsorption of tetrahydrothiophene (THT) and thiophene (TP) on Au(111) were investigated by means of scanning tunneling microscopy (STM) and carbon K-edge near edge X-ray absorption fine structure (NEXAFS) spectroscopy. STM imaging revealed that THT SAMs have a commensurate (3 ${\times}\;2\sqrt[]{3}$) structure containing structural defects in ordered domains, whereas TP SAMs are composed of randomly adsorbed domains and paired molecular row domains that can be described as an incommensurate packing structure. The NEXAFS spectroscopy study showed that the average tilt angle of the aliphatic THT ring and $\pi$-conjugated TP ring in the SAMs were calculated to be about $30^o\;and\;40^o$, respectively, from the surface normal. It was also observed that the $\pi$* transition peak in the NEXAFS spectrum of the TP SAMs is very weak, suggesting that a strong interaction between $\pi$-electrons and the Au surface arises during the self-assembly of TP molecules. In this study, we have clearly demonstrated that the surface structure and adsorption orientation of organic SAMs on Au(111) are strongly influenced by whether the cyclic ring is saturated or unsaturated.

• 한국농림기상학회지
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• 제11권4호
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• pp.127-134
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• 2009

본 실험은 '후지'/M.9 재배체계에 있어 최근 문제시되는 일소증상 발생에 미치는 한여름의 기온 요인을 구명하기 위하여 실시되었다. 일소증상은 최고기온이 $31^{\circ}C$이상인 누적일수 및 하루 누적 총광량이 많을수록 발생이 증가하였다. 상대적으로 개방된 수관을 형성한 '후지'/M.9은 '후지'/M.26보다 과실이 광에 노출되기 쉬워 일소증상 피해가 더 컸다. '후지'/M.9 사과나무 중에서는 과대지 길이가 짧은 나무에서 일소증상 피해가 더 컸다. 일소증상 발생은 재배지역 및 재식 열방향에 영향을 받지 않았고, 주로 남쪽과 서쪽에 착과 된 과실에서 일소증상 발생이 많았다. 그 이유는 과실이 직사광선에 노출되어 과실온도가 $40{\sim}45^{\circ}C$를 넘었기 때문으로 판단되었다.

• 제어로봇시스템학회논문지
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• 제20권2호
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• pp.200-210
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• 2014

An active virtual impedance algorithm is newly proposed to track a sound source and to avoid obstacles while a mobile robot is following the sound source. The tracking velocity of a mobile robot to the sound source is determined by virtual repulsive and attraction forces to avoid obstacles and to follow the sound source, respectively. Active virtual impedance is defined as a function of distances and relative velocities to the sound source and obstacles from the mobile robot, which is used to generate the tracking velocity of the mobile robot. Conventional virtual impedance methods have fixed coefficients for the relative distances and velocities. However, in this research the coefficients are dynamically adjusted to elaborate the obstacle avoidance performance in multiple obstacle environments. The relative distances and velocities are obtained using a microphone array consisting of three microphones in a row. The geometrical relationships of the microphones are utilized to estimate the relative position and orientation of the sound source against the mobile robot which carries the microphone array. Effectiveness of the proposed algorithm has been demonstrated by real experiments.