• Journal of Forest and Environmental Science
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• v.6 no.1
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• pp.1-7
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• 1989

The fine structures of the Primary and the secondary tissues in Pinus densiflora were examined by X-ray diffraction method. The results obtained are summarized as follows; 1. D-spacings of (200) and (004) Planes had little difference in both tissues. 2. The crystallinity index of the primary tissue as observed was 23%, while that of the secondary tissue was 35%. 3. The lateral crystallite size of both tissues had almost equal values. 4. The crystalline substances of the primary and the secondary tissues showed different patterns of orientation. The former had a random orientation, whereas the latter showed an orientation of 20 to 25'.

• Design & Manufacturing
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• v.12 no.2
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• pp.27-33
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• 2018

Korea's automobile industry, which has grown rapidly to become the world's fifth-largest automobile producer, To cope with environmental pollution and energy problems in order to prevail competitive edge in global market We are investing a lot of research personnel and costs. Among them, for realizing alternative light weight It is a part of the automobile module system that has achieved the technological development before the breakthrough in the injection molding process in the press process. Door module PNL was the subject of research. The door module PNL is expected to cause warpage before the mold production due to the thin and flat product characteristics and fiber orientation characteristic of the material. In this paper, CAE analysis and reverse correction tool Design. CAE analysis to obtain the results of weld line position, bending position and deformation value Through the correction tool, think3, the original product was modified before the mold production to improve the completeness of the parts. In fiber orientation, the position and size of the cooling channel in the mold, the position and size of the gate, Temperature, pressure, time, and work environment. Compared with the result of CAE analysis, the product that was reverse-corrected by Think3 was manufactured, and injection molding was performed. Injection molding products were tested 24 hours later. 3.5 mm to 7.0 mm, and under the fixed condition, the deviation was from 1.1 mm to 1.5 mm. Unlike the CAE analysis, the deviation of the actual injection pressure and the cooling temperature, the fiber orientation of the material, In order to solve this problem, it is necessary to compare the injection conditions with the database, I knew I had to catch the standard.

• Journal of Digital Convergence
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• v.19 no.12
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• pp.231-241
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• 2021

The consulting industry is also growing as the use of management consulting increases as the importance of management strategies for the survival of companies due to rapid environmental changes is highlighted. As a result, competition among consulting firms is intensifying, and securing competitiveness is essential. This study tried to confirm the method of securing competitiveness of consulting firms from the perspective of organizational competitiveness through organizational effectiveness. As the consulting service is a knowledge service field, an empirical analysis was conducted for consultants who performed it because professional human resources were a core technology. Exploratory factors, reliability analysis, and regression analysis were performed using SPSS 22.0. As a result of a study on the effect of consultants' organizational effectiveness on customer orientation, it was found that the consultant's organizational commitment and organizational performance had a significant effect. It was possible to confirm the importance of intrinsic motivation to secure the competitiveness of consulting firms in the changing environment. This presented practical implications for organizational management regarding the continuous growth of consulting firms.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.1
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• pp.239-246
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• 2019

The drone photogrammetry is actively utilized for obtaining highly accurate spatial information and other various monitoring purposes. It is general to plan the drone photogrammetry by referring to previous experiences or cases in order to obtain the required accuracy, but the drone photogrammetry is often carried out again due to poor accuracy. Since the required spatial accuracy of the drone photogrammetry process result becomes the means of objective evaluation regardless of the type of result, it should be determined carefully. Therefore, it is necessary to determine flight height, overlap, number and arrangement of ground control point, and exterior orientation factor acquisition method in order to meet the required 3D positional accuracy for the design of drone photogrammetry project. In this study, previous study cases for the analysis of drone photogrammetry accuracy were carefully analyzed and verified by applying such cases to testing area, and design guideline of drone photogrammetry project for a small area was prepared based on the analysis result. The presented project design guideline is expected to be a great help to business practice although it is not perfect, and if the design guideline is prepared through comprehensive analysis in future, it would be possible to provide a perfect manual.

• Journal of the Korea Convergence Society
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• v.11 no.12
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• pp.137-145
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• 2020

The purpose of this study is to analyze the relationship between the two factors and the influence of Chinese cultural orientation on the change of physical dry environment in the domestic Chinese residential area. To this end, Hofsted's cultural dimension theory, which can quantitatively define and compare the national culture, is used to investigate the cultural orientation of China. The association was analyzed. Through this study, it was confirmed that the collectivist and uncertainty-avoidance tendency of the Chinese influenced the formation and change of the dry environment of the Chinese residential area in Daelim 2-dong. This study is meaningful in confirming that the cultural orientation of the migrant community affects the formation and change of collective residences, and through this, it can be used as basic data in preparing policies suitable for various migrant communities including Chinatown.

• Korean Journal of Psychosomatic Medicine
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• v.7 no.2
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• pp.213-225
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• 1999

Objectives : The purpose of this study was to investigate how the play habits, temperament, and environmental factors might affect childhood obesity. Methods : Two hundred sixty children, aged 4 through 6 years living in Seoul & Cheonan were surveyed by a questionnaire about the children's play habit and the parent's related factors such as weight, height, education, income. In addition the Korean version of the Parent Temperament Questionnaire for Children and the Korean version of the Family Environment Scale were also administered to parents of those children. The height and weight of those children were measured and the percentage of body fat was measured by Bioelectrical Impedance Fatness Analyzer. Result : 1) Among 260 children, 25 children were considered to be obese on the basis of both obesity index and percentage of body fat. 2) Parents of obese children showed a significantly higher educational level(p<0.05) and mothers of obese children had significantly more jobs(p<0.05) and showed higher body mass index(p<0.05) than those of nonobese children. 3) By observing play habits of children, obese children spent significantly longer time in watching TV and video(p<0.05), while nonobese children showed a trend to play outside(p<0.1). 4) On the Korean version of the Parent Temperament Questionnaire for Children, obese children showed significantly less activity than nonobese ones(p <0.05). 5) Family of obese children had significantly higher point on subscale of Achievement orientation, Intellectual-cultural orientation and Moral-religious emphasis of the Korean version of the Family Environment Scale(p<0.05). 6) Percentage of body fat of obese children was correlated with children's watching TV time, activity level, scores of Achievement orientation, Intellectual-cultural orientation of the Korean version of the Family Environment Scale and the both parent's education levels(p<0.05). Conclusion : Obese children showed hypoactivity and more watching TV time. And obese children's both parent had higher educational level and their mother had higher Body Mass Index and more jobs. Family of obese children had higher point on items of Achievement orientation, Intellectual-cultural orientation and Moral-religious emphasis. Family environmental factors influence on children's obesity through interaction of genetic and behavioral-psychological factors concomittently.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.12
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• pp.583-595
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• 2002

Homing operation can be defined as a series of actions which are necessary for a mobile robot to move from the current position with any arbitrary orientation to a desired position with a specified orientation, while avoiding possible obstacles. In this paper, a homing and obstacle avoidance algorithm for nonholonomic mobile robots is proposed. The proposed algorithm consists of a local goal generator, a discrete state controller, and local path tracking controller based on Aicardi's path following algorithm. In the discrete state controller, 4 states are defined according to the environmental conditions and 4 desired high-level command for the states are given as follows: avoid, wander, home and homing zones. The proposed local goal generator is designed to generate the desired local path by using weighted distance transforms which are newly made to satisfy the nonholonomic constraints of mobile robots. Here, subgoals are also found as vertices of the desired local path. To demonstrate result effectiveness and applicability of the proposed algorithm, computer simulations are illustrated and experimental results for a real mobile robot system are also provided.

• Journal of The Korean Society of Agricultural Engineers
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• v.47 no.2
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• pp.15-21
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• 2005

This study is to trace the change of stream shape using the past series of aerial photographs, and to compare the land use changes of riparian area along the stream. For the Gyeongan national stream, aerial photographs of 1966, 1981 and 2000 were selected and ortho-photographs were made with interior orientation and exterior orientation, respectively. Apparent changes of the stream were found that the consolidated reaches of stream by levee construction became straight together with widening of their stream widths. Especially the stream width of inlet part of Paldang lake widened almost twice because of the rise of water level by dam construction in 1974. The land use of riparian areas of three selected years were classified into six categories (water, forest, agricultural land, urban area, road, sandbar) by digitizing method. The forest and agricultural lands decreased and urban area increased as the stream maintenance had been performed.

• Journal of Mechanical Science and Technology
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• v.15 no.8
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• pp.1097-1107
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• 2001

In this paper, the wall following navigation algorithm of the mobile robot using a mono vision system is described. The key points of the mobile robot navigation system are effective acquisition of the environmental information and fast recognition of the robot position. Also, from this information, the mobile robot should be appropriately controlled to follow a desired path. For the recognition of the relative position and orientation of the robot to the wall, the features of the corridor structure are extracted using the mono vision system, then the relative position, the offset distance and steering angle of the robot from the wall, is derived for a simple corridor geometry. For the alleviation of the computation burden of the image processing, the Kalman filter is used to reduce search region in the image space for line detection. Next, the robot is controlled by this information to follow the desired path. The wall following control scheme by the PD control scheme is composed of two control parts, the approaching control and the orientation control, and each control is performed by steering and forward-driving motion of the robot. To verify the effectiveness of the proposed algorithm, the real time navigation experiments are performed. Through the result of the experiments, the effectiveness and flexibility of the suggested algorithm are verified in comparison with a pure encoder-guided mobile robot navigation system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.6
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• pp.2289-2301
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• 2015

Mobile devices are becoming powerful enough to realize augmented reality (AR) application. This paper introduces two AR methods to estimate an environmental illumination distribution of a scene. In the first method, we extract the lighting direction and intensity from input images captured with a front-side camera of a mobile device, using its orientation sensor. The second method extracts shadow regions cast by three dimensional (3D) AR marker of known shape and size. Because previous methods examine per pixel shadow intensity, their performances are much affected by the number of sampling points, positions, and threshold values. By using a simple binary operation between the previously clustered shadow regions and the threshold real shadow regions, we can compute efficiently their relative area proportions according to threshold values. This area-based method can overcome point sampling problem and threshold value selection. Experiment results demonstrate that the proposed methods generate natural image with multiple smooth shadows in real-time.