• International Journal of Industrial Entomology and Biomaterials
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• v.42 no.2
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• pp.33-45
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• 2021

Many researchers are using the heterosis, heterobeltiosis and hybrid vigour over check parent value formulae to determine the hybrid vigour for animals, plants and silkworm breeding. These formulae are ideal for determine the hybrid vigour for the positive direction of single trait. It is difficult using these formulae for multiple traits. Suggested modification for cardinal formulae were made as well as suggestion new formula for determines hybrid vigour for multiple traits. Modifications of hybrid vigour were made to facilitate judgment of best hybrids under study for multiple traits. Nineteen local hybrids of mulberry silkworm were prepared for these investigations in addition the imported Bulgarian hybrid. Comparison between the cardinal and the modifications formulae were applied for thirteen economic characters. Nine positive and four negative direction characters were observed. Modified formulae make the judgment of heterobeltiosis, heterosis and hybrid vigour over check parent value very facilitate for positive and negative traits.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.6
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• pp.2971-2978
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• 2013

Recently, with the world-wide issues about global warming and CO2 reduction, a number of distributed generations(DGs) such as photovoltaic(PV) and wind power(WP), are interconnected with the distribution systems. However, DGs can change the direction of the power flow from one-direction to bi-direction, and also change the direction and amount of fault current of existing distribution systems. Therefore, it may cause the critical problems on the power quality and protection coordination. This paper proposes an operation algorithm for bi-directional protection coordination using and apply it for the evaluation system for protection coordination. From the simulation results It is found that the proposed method is more effective and convenient than existing method.

• Journal of the Korean Institute of Rural Architecture
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• v.15 no.4
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• pp.69-78
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• 2013

The location of villages differs by position, and the method to form the conditions of location varies greatly. This study has comprehensively investigated village layout in the riverside and directional relations in houses. With changes in riverside landscape and transition to an agriculture-oriented village, there have been changes in road and the size, shape and direction of houses as well. In terms of the direction of houses situated along the river, a house facing the river accounts for more than half of all houses in the village. As traditional houses are transformed into modern houses over time, houses have become bigger, and the number of the houses facing south or southeast has been on the rise. As described above, riverside landscape and preference for the house facing south have an effect on determination of the facing direction of houses. However, the direction of geographical features of the village was first followed, and other conditions have been reflected, and the characteristics for the facing direction of houses have been observed.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.3
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• pp.226-231
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• 2008

In this paper, we propose novel eigenstructure assignment method in full-state feedback for linear time-invariant MIMO system such that directions of some left eigenvectors are exactly assigned to the desired directions. It is required to consider the direction of left eigenvector in designing eigenstructure of closed-loop system, because the direction of left eigenvector has influence over excitation by associated input variables in time-domain response. Exact direction of a left eigenvector can be achieved by assigning proper right eigenvector set satisfying the conditions of the presented theorem based on Moore's theorem and the orthogonality of left and right eigenvector. The right eigenvector should reside in the subspace given by the desired eigenvalue, which restrict a number of designable left eigenvector. For the two cases in which desired eigenvalues are all real and contain complex number, design freedom of designable left eigenvector are given.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1341-1344
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• 2009

A novel method to control the viewing direction by moving aperture location in 4-f illumination optics to control light direction is proposed. Based on integral imaging principle, the relayed point light sources by 4-f optics are modulated by a spatial light modulator, displaying three-dimensional images. In the proposed method, we locate the aperture, which acts as a band pass filter, around an optic axis to control the light direction. Resultantly, assuming that we know the viewer position by a tracking system, we can display appropriate three-dimensional images over large viewing angle.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.8
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• pp.52-59
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• 2021

In this study, we experimentally evaluated the mechanical properties and geometric form accuracy in FDM 3D printing processes based on the printing direction, building direction, and layer thickness. The specimen test results showed that the tensile strength increased by over 33% in the printing direction compared to the direction perpendicular to printing and the tensile strength becomes larger as the layer thickness decreased. Furthermore, the tensile and impact strengths in the building direction were significantly reduced due to the difference in the interlayer joining and bonding strengths of the fused material. Additionally, shrinkage of the material due to phase change induced curl distortion especially in thin and long 3D-printed products, which increased as the layer thickness increased.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.3
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• pp.379-386
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• 2007

In this paper, topographic factors over 3-dimensional hills were estimated through wind tunnel tests. Topographic models having five different slopes of $5.71^{\circ}, \;11.31^{\circ},\;16.70^{\circ},\;21.80^{\circ}$, and $26.57^{\circ}$ which were based on Korean Building Code(KBC(2005), were made for wind tunnel tests. From the result of wind tunnel tests, topographic factors over 3-dimensional hills were obtained at various locations, and the ranges of topographic effects were decided. The ranges of topographic effects was whole area of the hills in the horizontal ranges and heights of 3.5 times of the hills in the vortical ranges. Topographic effects was large at the top of hills, and wind velocity was increased 57% over hill of $5.71^{\circ}$, 75% over hill of $11.31^{\circ}$, 79% over hill of $16.70^{\circ}$, 81% over hill of $21.80^{\circ}$, and 61% over hill of $26.57^{\circ}$. Wind velocity was bigger over surface of across-wind direction of hills than one over surface of wind direction of hills, and wind velocity was increased $10{\sim}30%$ at locations of across-wind direction.

• Journal of Environmental Science International
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• v.19 no.10
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• pp.1187-1201
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• 2010

The formation and development conditions of the cloud streets over the yellow sea by the Cold Surge of Siberian Anticyclone Expansion which produce the heavy snowfall events over the southwestern coast, Honam District of the Korean peninsula, has been investigated through analyses of the three dimensional snow cloud structures by using the CAPPI, RHI, VAD and VVP data of X-band Radar at Muan Weather Observatory and S-band Radar at Jindo Weather Station. The data to be used are obtained from January 04, 2003, when heavy snow storm hits on Gwangju and Honam District. The PPI Radar images show that the cloud bands distribute in perpendicular to the expansion direction of the high pressure and that the radius of cloud cells is about 5~8 km with 20~30 dBz and distance between each cell is about 10 km. And but the vertical Radar images show that the cloud street is a small scale convective type cloud within height of about 3 km where a stable layer exists. From the VVP images, the time period of the high pressure expansion, the moving direction and development stages of the system are delineated. Finally, the vertical distribution of wind direction is fairly constants, while the wind speed sheer increases with altitude to 3 km.

• Culinary science and hospitality research
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• v.13 no.3
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• pp.207-219
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• 2007

The purpose of this study is finding the right direction to make the best career development systems for the employees in hotel industry in Korea. The condition of the best career development system is satisfaction from companies and employees each other. However, making that condition is not easy for every industry as well as for hotel industry over the world. In this respect, we can find the three directions of career development for applying the systems to the employees like strategy direction oriented, development direction oriented and employee satisfaction oriented. Among those directions, we have to find the best direction for individual satisfaction and organizational company satisfaction. This study will help to make and execute the plan for career development in real hotel industry fields, especially for the policy of human resources management. In this study, we can see the importance of employees' satisfaction for managing a hotel. The increasing productivity of the hotel eventually will be made from career development through employee satisfaction.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.17 no.1
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• pp.39-45
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• 2009

An Analysis of wind is essential for planning runway direction. As a general rule, the principal traffic runway at an airport should be oriented as closely as practicable in the direction of the prevailing wind. Aircraft are able to maneuver on a runway as long as the wind component at right angles to the direction of landing and taking-off, the cross wind component, is not excessive. ICAO recommends that runway be oriented so that aircraft may be landed at least 95% of the time with allowable cross wind components not exceeding specified limits based upon the airport reference field length. Based on the recommendation, the direction of the runway or runways at an airport can be determined through graphical vector analysis on wind rose. This study is to develop the wind-rose software for planning the optimum runway direction at an airport with the raw wind data based on reliable wind distribution statistics that extend over as long as a period as possible, preferably of not less than 5 years.