• 제어로봇시스템학회논문지
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• 제21권5호
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• pp.471-476
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• 2015

This paper presents a maximum velocity trajectory planning algorithm for differential mobile robots with wheel velocity constraint to cope with physical limits in the joint space for two-wheeled mobile robots (TMR). In previous research, the convolution operator was able to generate a central velocity that deals with the physical constraints of a mobile robot while considering the heading angles along a smooth curve in terms of time-dependent parameter. However, the velocity could not track the predefined path. An algorithm is proposed to compensate an error that occurs between the actual and driven distance by the velocity of the center of a TMR within a sampling time. The velocity commands in Cartesian space are also converted to actuator commands to drive two wheels. In the case that the actuator commands exceed the maximum velocity the trajectory is redeveloped with the compensated center velocity. The new center velocity is obtained according to the curvature of the path to provide a maximum allowable velocity meaning a time-optimal trajectory. The effectiveness of the algorithm is shown through numerical examples.

• 로봇학회논문지
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• 제13권2호
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• pp.142-149
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• 2018

$RRT^*$ (Rapidly exploring Random $Tree^*$) based algorithms are widely used for path planning. Informed $RRT^*$ uses $RRT^*$ for generating an initial path and optimizes the path by limiting sampling regions to the area around the initial path. $RRT^*$ algorithms have several limitations such as slow convergence speed, large memory requirements, and difficulties in finding paths when narrow aisles or doors exist. In this paper, we propose an algorithm to deal with these problems. The proposed algorithm applies the image skeletonization to the gridmap image for generating an initial path. Because this initial path is close to the optimal cost path even in the complex environments, the cost can converge to the optimum more quickly in the proposed algorithm than in the conventional Informed $RRT^*$. Also, we can reduce the number of nodes and memory requirement. The performance of the proposed algorithm is verified by comparison with the conventional Informed $RRT^*$ and Informed $RRT^*$ using initial path generated by $A^*$.

• 한국조경학회지
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• 제18권3호통권39호
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• pp.143-154
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• 1990

This study aims at identifying factors and variables which have significant effects on users satisfaction with recreational activities and facilities in Apsan city natural park and therby establishing indicies of planning and / or development of urban forest. To test the causal models of this research, The data were gathered by self-administered questionnaires from 1,147 households in Taegu city which were selected by the multi-stage probabiling sampling method. The analysis of the data primarily consist of two phases : The first analysis dealt with exploratory factor analysis which identified major factors involved in satisfaction with recreational activities and facilities in Apasn city natural park and the second analysis tested the fit of causal models of this research to the data using LISREL methodology. The factor analysis identified that three significant factors are involved in satisfaction with recreational activities and five significant factors are inherent in satisfaction with recreational facilities. The second phase analysis tested the fit of the causal models for satisfaction with recreational activities and facilities to the data and identified statistically significant causal linkage among overall satisfaction with the park, other indogenous factors and exogenous variables. These significant relationships represent important factors and variables that should be considered in planning and/of development of the city natural park. On the basis of there significant causal relationships implications for planning and/or development of the city natural park were suggested.

• 한국조경학회지
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• 제15권3호
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• pp.21-31
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• 1988

This study was executed to investigate the vegetation structure and to propose the administration planning of the Royal Ancestor's Shrine. Five sites sampled in the study area with the clumped sampling method. Pinus koraiensis community covered 27.3% and Quercus aliena community 61.5% of total forest area when considering the actual vegetation. This area of environmental impact grade 3 and 4 area covered 46.9% and it should be restored. The ecological diversity, i.e. species diversity and evenness, showed low class, and especially site 2 which was controlled the user's after 1985 showed the lowest value. Pinus koraiensis community which is a dominant species now in the study area shall be succeed to Quercus aliena community. Robinia pseudoacacia at the eastern wall shall be excluded step by step and it shall be replaced with native species gradually. Ailanthus altissima, Populus ${\times}$ albaglandulosa and Styrax japonica which had higher selection invaded conspicuously the bare land. As the administration planning of the study area, Pinus koraiensis and Styrax japonica shall be thinned out gradually and it shall be replaced with Quercus aliena and Acer palmatum.

• The Journal of Asian Finance, Economics and Business
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• 제8권3호
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• pp.619-628
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• 2021

Enterprise system (ES) reflects a significant IT commitment to achieve corporate goals and satisfy its thrust toward a sustainable competitive advantage. This research investigates the required ES architecture, the value of a well-planned ES, and the human factor capabilities that drive the effective implementation of ES from a management perception. This paper examined the critical factors shaping the business systems' performance, architecture readiness, experts' readiness, and enterprise systems planning. Based on an extensive literature review, the attributes of factors mentioned earlier were identified, classified and then statistically examined using the author's' proposed conceptual structural model. This study employs a quantitative research methodology, with a random sampling technique. This paper has used the data collected from 510 respondents working in service, engineering and health sectors in OMAN. The study model analysis utilized both exploratory and confirmatory factor analysis, followed by a structural equation modeling using SPSS 25 and EQS6.3 statistical tools. The results unveil a piece of remarkable and robust evidence suggesting that ES planning is the most significant aspect of influencing performance, followed by IT personnel, staff and consumers expertise, and architecture readiness.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제2권3호
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• pp.144-152
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• 2021

Sanankerto is one of pilot projects for tourism villages in Indonesia due to its natural tourism potential with a 24-ha bamboo forest located in Boon Pring Andeman area. However, the distribution of existing bamboo has never been identified or mapped. Thus, the mana gement is facing difficulty in planning and developing tourism potential as well as spatial management in the area. Therefore, the objectives of this study were to identify and analyze the structure of bamboo vegetation in the Boon Pring Tourism village an d to perform vegetation mapping. The type of research was descriptive exploratory with a cluster sampling technique (i.e., a two-stage cluster) covering an area of ± 10 ha. Bamboo vegetation analysis was performed by calculating diversity index (H'), evenness index (E), and Species Richness index (R). Data were collected through observation and interviews with local people and the manager to determine zonation division. Mapping of bamboo vegetation based on zoning was processed into thematic maps using ArcG is 10.3. Micro climatic factors were measured with three replications for each sub -cluster. Data were analyzed descriptively and quantitatively. Nine species of bamboo identified. Diversity, evenness, and species richness indices differed at each location. Activities of local communities, tourists, and manager determined the presence, number, and distribution of bamboo species. These bamboo distribution maps in three zoning (utilization, buffer, and core) can be used by manager for planning and developing natural tourism potential.

• 자원환경지질
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• 제37권1호
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• pp.49-59
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• 2004

The concectration and distribution of contaminants obtained from a contaminated land investigation or an environmental geochemistry survey constitutes the basis of a decision-making process on environmental policies or of scientific researches. As the quality of data determines the reliability of the result, the investigation plan should be adjusted according to the purpose of the investigation. In general, the effort to improve the data quality had been focused mainly on the QA/QC procedures in laboratories. The rapid progress of analytical instrument has also contributed toward improving the analytical precision to a sacrificable degree. Nevertheless, in many cases, it is not the analytical precision that needs improvement for the better precision of overall measurement process: it is rather during the sampling process in the field that is responsible for the poor precision. To assess the data quality on a measured value, ISO recommends to provide information on "measurement uncertainty" along with the measured value. The measurement uncertainty in an environmental measurement context can be explained as the statistical number that expresses the degree of the uncertainty stemming from the sampling and analytical procedures. There is a cost involved in order to improve the precision of sampling and analytical methods so as to decrease the degree of measurement uncertainty. The economical point of compromise in an investigation planning can be achieved when the allowable degree of uncertainty has been set before-hand. The investigation can then be planned accordingly not to exceed the uncertainty limit. Furthermore, if the measurement uncertainty estimated from the preliminary investigation can be separated into sampling and analytical uncertainties, it can be used as a criterion where the resources for the investigation should be allotted cost-effectively to reinforce the weakest link of the whole investigation process. This paper aims to present a method of estimating the level of measurement uncertainty of a measured contamination concentration at a site used as an example and to show how the estimated uncertainty can be applied to serve the particular purpose of an investigation.

• Nuclear Engineering and Technology
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• 제53권1호
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• pp.234-243
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• 2021

In the research or project planning for the decommissioning of a nuclear power plant, one of several preparations will be the establishment of a list of potential radionuclides to be considered at the time of characterization or final status surveys. Reliable data for selection of potential radionuclides during the transition period to prepare for decommissioning will depend heavily on historical data at the site or, where possible, sampling analysis. However, during the transition period, direct sampling can be challenging, depending on the circumstances of the site or national regulation. A methodology of selecting potential radionuclides for nuclear facility sites which largely consists of three major processes: production of initial list of radionuclides, selection of the insignificant radionuclide that will be eliminated, and consideration of site characterization or sampling. For developing a preliminary list of potential radionuclides for Kori Unit 1 decommissioning, the list of initial radionuclides was made referring to the technical documents applied at decommissioned NPPs in the U.S and additional reference materials applied until the operation of NPPs in Korea. For the screening of insignificant radionuclides, we applied criterion of less than 0.1% of the amount of radioactivity inventory and confirmed the dose fraction using the RESRAD code. The final suit of radionuclides was established, which should be supplemented by reflecting site characterization and sampling process in the future. Thus, the methodology and results for the selection of potential radionuclides suggested in this paper can give an insight as a future reference to deriving DCGLs in relation to site remediation of decommissioning nuclear plants.

• 한국실내디자인학회논문집
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• 제26권1호
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• pp.114-123
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• 2017

The objective of this paper is to investigate problems associated with the storehouse affiliated with rural housing for the elderly engaged in farming activities, and to suggest improvements with the examples of storehouse floor plans. The elderly in rural area still engage in farming even though they are suffering from aging problems. Therefore, the planning of storehouse which has relevance to agriculture is very important. The methods employed were a field survey and interviews with residents. 12 houses belonging to elderly people (60's and over) were selected by the convenient sampling in Cheonan, Chungcheongnam-do. The results are as follows. First, at least more than 3 storehouses have to be planned to store the goods separatedly according to their kinds and characteristics. Second, storehouses should be placed near or directly connected with the main house to support the accessibility of the elderly. Third, the open space has to be planned in front of the storehouse to park a truck for loading goods directly. Fourth, the storage equipments such as shelves should be planned inside of the storehouse for the space efficiency and user convenience. Fifth, the width of the door should be wide enough to carry agricultural products and goods. It is recommended to use double hinged doors or double pocket doors. Besides, the thresholds of the doors should be removed and, rather than using direct lighting system, it is better to use indirect lightings and task lightings together to minimize glare and to provide enough illumination.

• 복식
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• 제53권2호
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• pp.87-100
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• 2003

In this study, the modern street fashion of Kangnam and Kangbuk was qualitatively examined and comparatively analyzed through the field case study, and it is expected that the results of this study be importantly used in planning commodity of fashion brand. The photographs taken in the Kangnam and Kangbuk streets were classified as looks. which were comparatively analyzed each other. Also, a questionnaire was carried out in return for women in those streets, and data related with an age group, occupation, school, academic major, etc. for participant personality and with time purchasing clothing. average expenses for clothing per month. market and reasons for buying clothing, current fashion style, etc. for fashion preference trend were obtained. The streets around Kangnam subway station and KOEX mall for the Kangnam fashion style were selected for the sampling, and Sinchon and entrance of Ewha University for the Kangbuk, where college students and middle/high school students mostly gather. Results showed that an easy casual style was most popular in the Kangbuk area, and a romantic feminine style including a bobos style most popular in the Kangnam area. This case studied on the street fashion gaves the qualitative results about the fashion trend and fashion prediction information, and they could be compared with quantitative those known previously. Also, it could be a basis research on strengthening the competitive power in fashion commodity. However, this study was subjected to restriction in the sampling due to the short time and a few streets. This study will be extended into longer time and various streets including Apgujungdong in Kangnam and many colleges in Kangbuk.