• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.255-255
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• 2022

• Proceedings of the Korean Society of Crop Science Conference
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• 2020.06a
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• pp.132-132
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• 2020

• Proceedings of the Korean Society of Crop Science Conference
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• 2020.11a
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• pp.140-140
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• 2020

• Proceedings of the Korean Society of Crop Science Conference
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• 2021.10a
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• pp.175-175
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• 2021

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.04a
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• pp.18-18
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• 2022

• Proceedings of the Korean Society of Crop Science Conference
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• 2021.04a
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• pp.96-96
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• 2021

• Journal of Positioning, Navigation, and Timing
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• v.12 no.3
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• pp.307-314
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• 2023

Wide-Area Differential Global Positioning System (WADGPS) is a system that operates a number of reference stations to provide correction information to improve the accuracy of GPS users, and it is available to service users within the area where the wide-area reference stations are installed. Recently, as positioning information has been used in various applications, the need for WADGPS for precise navigation in long-distance spaced areas where the wide-area reference stations cannot be installed has been raised. This paper tested the user navigation performance outside the wide-area reference stations of the WADGPS system, which serves both GPS Precise Positioning Service (PPS) and Standard Positioning Service (SPS) users. Static and dynamic tests were conducted using vehicles, and as a result, position accuracy improvement through WADGPS was confirmed even at points hundreds of kilometers outside the network area of the wide-area reference stations. Through this, the performance of the PPS/SPS correction system and the possibility of expanding the service area were confirmed.

• The Korean Journal of Ecology
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• v.7 no.4
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• pp.203-207
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• 1984

This report is an investigation of the revegetation and secondary succession in the burned area of Mt. Sanseung in Taegu region. The forest fire took place in December, 1977. The survey was conducted eight times, -three times from October 1, 1983 to October 3, the same year and five times from August 10, 1984 to August 15, the same year. The floristic compositions in the sampled sites constituted 25 kinds of vascular plants and 21 kinds in the burned area and the unburned area respectively. The biological type in both the burned and unburned areas was H-D1-R5-e type, which is generally common to other areas (Taegu, Kyungpook, Chung Buk and Kangweon areas). In the burned area dominant species were Carex humilisvar. nana, Arundinella hirata and Quercus serrata and on the other hand, in the unburned area Pinus densiflora, Carex humilis var. nana, Rhododendron mucrfonulatum var. ciliatum and Quercus serrata. The species diversity diversity index(H) and eveness index(e) of the burned area were higher than those unburned area. Degree of succession (DS) was 650 in the burned area at the 6th years after the fires and 962 in the unburned area. THe vegetation of the burned area was slowly recovered as of 1984 compared with each other. According to the analysis of the soil preperties, pH, available phosphorus and exchangeable potassium were increased, but organic matter, total nitrogen and total organic carbon were decreased. It is assumed that these results were due to the forest fire.

• Journal of Korean Society of Transportation
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• v.23 no.5 s.83
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• pp.65-71
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• 2005

Area type is often used in freight demand analysis and logistics planning models. For example, in freight transportation planning. area type variable is most often commonly used in freight generation (attraction) model. Yet a reliable, forecastable and measurable definition or area type is generally not documented. In fact, there is little literature on the subject of predicting area type in the context of freight planning models. This can be troublesome when applying models to long-range logistics planning where significant changes in population and employment result in changes in the general character of an area. Through the use of Discriminant Model, GIS (Geographic Information System) analysis and Delphi methods, this paper presents the successful exploration for a quantifiable means of determining area type.

• Journal of Periodontal and Implant Science
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• v.26 no.4
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• pp.859-872
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• 1996

The purpose of this study was to evaluate the effect of low concentrative ${\beta}-APN$ on the periodontal ligament and relationship between lathyrintic bodies and osteoclast cells near the by alveolar bone. Mandibles including teeth and periodontiums of 24 Sprague-Dawley rat was used. ${\beta}-APN$ 0.2g/kg/day soluted in mineral water was administrated for 5 days before sacrifice in experimental group. 3 rats on each day was sacrificed on 1, 3, 7, 11 days after stop administration ${\beta}-APN$. Histologic examination and the activity of osteoclasts by tartrate resistant acid phosphatase was observed. The results were as follows : 1. In experimental group, the The small foci of lathyrintic bodies surrounded by palisading fibroblasts were seen obviously on 1, 3 days and decreased after 7 days. On 11 days, fibroblasts of periodontal ligament similar to control group. 2. The lathyrintic bodies were seen in the middle zone of periodontal ligament of pressured area like furcation area, alveolar crest, bone resorption area than tensioned area of apposition area. 3. In experimental group of 1, 3 days, lathyrintic bodies were much seen in the area that osteoclasts was much distributed area. After 7 days, experimental group was seen the control group. In conclusion, rathyrintic bodies were formed by low concentrative ${\beta}-APN$ chiefly on the pressured area like furcation area, alveolar crest, bone resorption area than tensioned area of apposition side in periodontal tissue and concerned with osteoclast cells.