• International Journal of Highway Engineering
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• v.19 no.6
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• pp.97-103
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• 2017

PURPOSES : In this study, the pavement condition of non-mill-and-overlay and mill-and-overlay on deteriorated concrete pavement was compared. In addition, the suitable time to perform the initial overlay was investigated. METHODS : The condition of the pavement sections that were not additionally overlaid on non-mill-and-overlay or mill-and-overlay on deteriorated concrete pavements was investigated according to overlay pavement age. The condition of non-mill-and-overlay and mill-and-overlay sections of expressway route 25, which has more information on overlay history than other routes, was compared according to the number of times of overlay. The relation between the concrete pavement condition just before the overlay and the number of times of overlay was investigated for the non-mill-and-overlay and mill-and-overlay sections for which the first overlay was performed in the same year. RESULTS : The pavement condition of the non-mill-and-overlay sections was better than that of the mill-and-overlay sections, showing higher Highway Pavement Condition Index(HPCI) regardless of overlay pavement age. The number of reflection crackings of the non-mill-and-overlay sections was smaller than that of the mill-and-overlay sections. As a result of observing the cores obtained from the overlay sections, the proportion of the deteriorated non-mill-and-overlay sections was smaller than that of the mill-and-overlay sections. The SD measured just before the overlay on the concrete pavement for which additional overlay was not performed was smaller than that for which additional overlay was performed regardless of the milling of the concrete slab surface. The HPCI of the concrete pavement for which overlay was performed just once was higher than that for which overlay was performed more than one time. CONCLUSIONS : Accordingly, it was concluded that the condition of the non-mill-and-overlay sections was better than that of the mill-and-overlay sections. In addition, the better the condition of concrete pavement just before the initial overlay, the longer the duration of the overlay effect.

• Journal of Korean Society of Transportation
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• v.27 no.1
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• pp.117-127
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• 2009

This study analyzed the uncertainty of the forecasted link traffic flow, and estimated of the interval link flow using Korea Transport Data Base (KTDB) to consider those risks into the feasibility study. In the paper, the uncertainty was analyzed according to the stochastic variation of the KTDB origin-destination traffic. It was found that the uncertainty of the entire network traffic forecasts was 15.4% in average,. when the stochastic variation of the KTDB was considered. The results showed that the more congested the roads were, the bigger the uncertainty of forecasted link traffic flow were found. In particular, we estimated the variance of the forecasted traffic flow, and suggested interval estimates of the forecasted traffic flow instead of point estimates which were presented in the common feasibility studies. These results are expected to contribute the quantitative evaluation of uncertain road investment projects and to provide valuable information to the decision makers for the transport investment.

• Journal of the Korean association of regional geographers
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• v.19 no.4
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• pp.737-746
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• 2013

This study was carried out to suggest plan of earth surface erosion by typifying landforms in Gwangeung Forest. Elements of landform were classifyed as hierachical system by scale. Scale for classification set a decision as four categories. We could classify landforms which level zero is 4 levels of elements, level one is 6, level two is twelve, level three is twenty seven. However, micro landforms of valley bottom which is hard to mapping made a categorization as upper valley, middle valley, artificial channel valley. Plan for soil erosion suggested yarding corridor, landform management for surroundings of slope and bridge using rock and gravel, road construction for forest management stable bedrock rather than soil layer, repose angles and piling up rocks for channel walls, and setting up buffer zone when forest thinning be carried out. The result of this research will be expected to provide information for forest management of mountainous areas by landform types.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.5
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• pp.171-179
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• 2004

Today, the number of vehicle increased rapidly with the development of modem science technology, and it caused serious problems; traffic jam, accident and pollution etc. One of the solve methods these problems it is necessary to develope the vehicle navigation systems and it is already widely used to in field of military etc. Vehicle navigation system can increase the efficiency of traffic flow and offer at a drivers at a best driving conditions. In the vehicle navigation, most important thing is to measure of correct position. There are classifiable as three types. The first is G.P.S., method at artificial satellites which measures the present position and velocity any time, any where in the world at the same time. Secondly, a vehicle can determine its position and path information with a gyroscope and odometer signal, which is called Dead-Reckoning method. Thirdly, hybrid navigation system is the combined of two methods to make utilize the advantage of each navigation system. In the paper, we are analyzed to characteristics at a gyro sensor and introduce at a composition of hybrid navigation system which is combined with the G.P.S., D.R., and map-matching technique. We analyze deeply for the Map-Matching method and explain the coordinate transformation for G.P.S., and the Hybrid navigation algorithm is developed and experimented. Finally, we conclude and comment about our road test results.

• Journal of Auto-vehicle Safety Association
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• v.7 no.1
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• pp.33-39
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• 2015

This study examined the drivers' acceptance level of various active safety features with Korean drivers on Seoul urban and city roads. The test vehicle, 2013 Cadillac ATS, was equipped with FCA(Forward Collision Alert), LDW(Lane Departure Warning), SBZA(Side Blind Zone Alert), FRPA(Front/Rear Park Assist), RCTA(Rear Cross Traffic Alert), ACC(Adaptive Cruise Control), and AEB(Autonomous Emergency Braking). Participants had chances to run the tests on those systems in the parking lot accompanied by the 106km long stretch of predetermined route including local road and interurban highway in Seoul and Gyeonggi-do under normal traffic flowing environment. After the test, participants completed a series of questionnaires about the features they experienced. The results revealed that RCTA and SBZA systems received more favourable ratings compared to the other features in avoiding crashes. The respondents preferred sound alerts to haptic ones even though haptic warning methods were better in providing directional information.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.8 no.3
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• pp.169-175
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• 2014

In this study, it is intended to provide a slip detector is an important function in the research on the slip control can be addressed uncontrollably path withdrawal might during driving of the power wheelchair, slip phenomenon occurs. By detecting and electric wheelchairs, the state of the motor during running, the detection of the slip, slip detection information calculated using an encoder that is connected to the left and right motor with six-axis IMU sensor for the electric wheelchair using an algorithm to calculate the slip ratio. Slip rate calculated in this way is used as control variable for improving the safety of the electric wheelchair. It was confirmed from the slip phenomenon of the path the proposed experiments slim detector proposed in this study. The maximum slip ratio detection zone during the experiment, can occur during turning of the electric wheelchair has been confirmed.

• Journal of Digital Convergence
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• v.14 no.11
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• pp.305-311
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• 2016

Even though automakers have actively been conducting studies on autonomous navigation thanks to the development and application of wireless Internet technology, the traffic accident has been kept unsolved. The causes of the accident are drowsy driving, a mistake of a driver, environmental factors, and a wrong road structure; Driving manner and characteristics of a driver among the causes are significantly influential for the accident. In this paper, a study to measure characteristics of zigzag driving that can be seen before an occurrence of an accident regarding traffic accidents that can be incurred while driving manually or autonomously was conducted. While existing studies measured zigzag driving based on characteristics of the change of lateral angular velocity by imaging techniques or driving manner on the first and second lane, this study proceeded to measure zigzag driving by setting a lateral moving distance and a critical value range by utilizing the value of a sensor.

• The Journal of Society for e-Business Studies
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• v.17 no.2
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• pp.39-62
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• 2012

Green IT is a necessary technology to solve the energy and environmental problems and to increase the productivity of corporations. However, till now there were not the specific policies for individual industries so we have to establish several strategies for spread of Green IT and building green growing environment. In this paper, we proposed the road map for spread of green IT and deducing the strategic directions for domestic industries. Four types of green IT direction was identified and in each direction, several action plans were discovered. We formed an expert-committee to choose new green IT business models and selected some demonstration projects by measures of necessity, urgency and extensibility. The object, scope, classification and policy effect are wrote out and it will be helpful information to disseminate green IT.

• Acta Via Serica
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• v.4 no.2
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• pp.119-128
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• 2019

This paper attempts to reveal little-known pages from the history of relations between the peoples of Central Asia and Korea based on materials derived from written sources and modern scientific literature, as well as from medieval wall paintings from the early medieval Afrasiab Palace of Varhuman, the ruler of Samarkand, and from stone sculptures of Sogdian figures contained in Silla royal tombs. Korea's interest in the western lands led to its contact with Buddhism, which spread and later flourished in all three Korean kingdoms (Koguryo, Paekche and Silla). The spread of Buddhism in turn motivated a number of Korean monks to undertake pilgrimages to India via Central Asia. Hyecho, a young Silla pilgrim, left evidence of his journey via the South China Sea to India in 723 AD. Paul Pelliot discovered a report from Hyecho's journey entitled Notes on Pilgrimage to Five Regions in India (Wang Wu Tianzhuguo zhuan) in the Dunhuang caves in 1908. Hyecho's contributions are worthy of attention, substantially complementing knowledge available for this little-studied period in the history of South and Central Asia. The information contained in Hyecho's manuscript is, in fact, considered the most significant work of the first half of the 8th century. Research regarding the relationship between Central Asia and Korea remains underdeveloped. Existing historical evidence, however, including the above mentioned Samarkand wall paintings, depicts the visits of two Korean ambassadors to Samarkand, and evidence from Silla tombs suggests the presence of diplomatic relations in addition to trade between the two regions. Overall, the history of the relationship between Central Asia and Korea yields new insights into how and why these distant countries sustained trade and diplomatic and cultural exchange during this early period. Taking into account Korea's growing interest in Uzbekistan, especially in its history and culture, this article can act as a catalyst for studying the history of the two country's relations.

• Journal of Cadastre & Land InformatiX
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• v.45 no.1
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• pp.137-150
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• 2015

The methodology on digital cadastre(World Geodetic System Conversion) needs to be specified because the primary target site is discussed for large national estate such as road, river etc. on nationwide. Comprehensively reviews on similar cases and literature reviews to make a methodology for digital cadastre on large national estate, cadastral map revision is required before converting to World Geodetic System. The revisions are on subdivision survey or the other surveys to the necessary area through inspection of geometry and attributes. And the researcher pointed out the need of registration conversion and union of parcel to remove small parcel or to remove the inconsistency of land use type. Basically a systematic maintenance of cadastral map is necessary because the World Geodetic System Conversion unresolved the poor cadastral map quality to digital cadastre on large national estate.