• Journal of Korean Society of Forest Science
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• v.88 no.2
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• pp.195-204
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• 1999

To improve nut production and timber quality in a plantation, crown shape controls were suggested for Korean white pines (Pinus koraiensis) under age class III through the analyses of the crown shape controls for seed orchard trees in several species, of crown status of controlled and uncontrolled trees in a Korean white pine seed orchard, and of growth characteristics of plantation trees under age class III. For nut production from the small trees less than 8 m, modified leader type can be applied by cutting the central leader and all branches below 1 m and keeping 4~5 nodes with 3~4 whorled branches a node locating 1 m apart. Trees with a 4~8 m long trunk below the first living branch are shaped into trees for nut and timber production, which have a 4~8 m long knotless stem and a modified leader type crown with 4~5 nodes with 3~4 whorled branches a node at a distance of 1 m. Trees, showing the first living branch at or above 9 m from the surface, are pruned severely for timber production and result in a central leader type containing two fifths of the initial crown. It is advisable to remove the leader and the branches when collecting cones or after/during October to take advantage of easy labor and little resin while cutting. After stem cut, branches showing apical dominance are to be cut to control height when necessary. The removal of the uppermost node may be needed to control the crown shape several years after the initial stem-cut.

• Journal of Korean Academy of Nursing Administration
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• v.4 no.1
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• pp.5-17
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• 1998

The Purpose of this study is to find out differences among the leader's traits on the hierarchy of Nurse managers in Nurse system of the hospital. In this study 152 managers over head nurse working in 6 University hospitals and 5 general hospitals were selected and the questionary paper answered by them was collected from 1st to 30th in September in 1997. The measuring instrument used in this study is the one integrated and classified by Stogdill (1981), which nurse professor and 2 students of the master's course translated and modified with myself. And its validity was verified through making a test on 130 nurses. The measuring instrument used in this study is made up of 4 items about physical characteristics, 3 items about social background, 4 items about intelligence and ability, 17 items about personaity, 6 items about task-related characteristics, 9 items about social characteristics and 8 items about general background in the triats of leader. And this instrument is made to be marked using five point Likert type. It's reliability is Cronbach's Alpha =.93. The data for study were analyzed through SPSS/PC+ The result of this study are as follows: 1. The order in importantly perceptible degree of the leader's traits showed like these: the intelligence and ability (M=4.683), the task-related characteristics (M=4.605), the personality (M=4.39), the social characteristics (M=4.327), the social back-ground (M=4.056), the physical characteristics (M=3.601). 2. The order in degree to percept the importance of 44 detailed items of the leader's traits showed like these: the judgement and decisiveness (M=4.967), the sense of responsibility (M=4.904), the activity and energy (M=4.796), the self-confidence (M=4.776), the creativity (M=4.748), the intelligence (M=4.743), the responsibility in the pursuit of objectives (M=4.743), the enthusiasm (M=4.717), the objectivity (M=4.704), the moral sense and ethical conduct (M=4.704), the ability to enlist cooperation (M=4.694), the strength of conviction (M =4.678), the enterprise (M=4.691), the administrative ability (M=4.678) and the cooperativeness (M=4.638) 3. As the result of analyzing the leader's trait differences on the hierarchy of nurse managers in six factors of the leader's traits, the social background showed the meaningful differences(F=4.983, P=0.008). 4. As the result of analyzing the leader's traits defferences made from the upper first to 15th rank among the detailed items of the leader's trait factors on the heirarchy of nurse managers, the meaningful defferences appeared in the following items: the objectivity(F=3.413, P=0.033), the creativity (F=3.550, P=0.031), the sense of responsibility(F=3.345, P=0.049), and the administrative ability (F=3.363, P=0.037). 5. As the result of analyzing the leader's trait factors in general background, only the social background of 6 leader's trait factors showed the meaningful differences according to the working place (F=4.057, P=0.008). The study shows that we should consider the above leader's trait factors in selecting nurse managers and that we should develop the educational program for hierarchy of nurse managers urgently.

• International Journal of Aeronautical and Space Sciences
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• v.14 no.2
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• pp.183-192
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• 2013

This paper presents formation reconfiguration using impulsive control input for spacecraft formation flying. Spacecraft in a formation should change the formation size and/or geometry according to the mission requirements and space environment. To modify the formation radius and geometry with respect to the leader spacecraft, the follower spacecraft generates additional control inputs; the two impulsive control inputs are general control type of the spacecraft system. For the impulsive control input, Lambert's problem is modified to construct the transfer orbit in relative motion, given two position vectors at the initial and final time. Moreover, the numerical simulation results show the transfer trajectories to resize the formation radius in the radial/along-track plane formation and in the along-track/cross-track plane formation. In addition, the maneuver characteristics are described by comparing the differential orbital elements between the reference orbit and transfer orbit in the radial/along-track plane formation and along-track/cross-track plane formation.