• 한국지능시스템학회논문지
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• 제8권2호
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• pp.134-141
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• 1998

시스템의 출력을 결정하는데는 실제적인 물리량보다는 상징적인 정보량이 필요할 때가 있다. 예를 들면 교차로 교통신호제어의 입력정보로 단순히 차량의 대수만으로는 정확한 신호제어를 할 수가 없다. 그러므로 도로의 길이, 폭과 차량의 형태 등을 고려한 도로의 혼잡량이라는 상징적인 정보량이 적합하다고 할 수 있다. 그러나 상징적인 정보량은 입력정보인 실제적인 물리량 사이에 서로 관련성이 없거나 상충적일 경우, 각 정보간의 선형성과 관련의식을 도출하여 상징적인 정보를 얻는다는 것이 어렵다. 본 논문에서는 상징적 정보량의 의미와 필요성을 교통신호처리 제어에 있어서 고찰하여 본후, 퍼지 이론을 통해 물리적인 교통 정보량을 이용하여 교통신호제어의 최종적인 출력 정보량인 교통 혼잡량을 산출하여 교통신호제어에 적용하여 기존의 교통신호제어 결과와 비교하였다.

• 제어로봇시스템학회논문지
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• 제20권9호
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• pp.950-956
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• 2014

In this paper, the real-time detection method of a DDP (Driving Direction Point) is proposed for an unmanned vehicle to safely follow the center of the road. Since the DDP is defined as a center point between two lanes, the lane is first detected using a web camera. For robust detection of the lane, the binary thresholding and the labeling methods are applied to the color camera image as image preprocessing. From the preprocessed image, the lane is detected, taking the intrinsic characteristics of the lane such as width into consideration. If both lanes are detected, the DDP can be directly obtained from the preprocessed image. However, if one lane is detected, the DDP is obtained from the inverse perspective image to guarantee reliability. To verify the proposed method, several experiments to detect the DDPs are carried out using a 4 wheeled vehicle ERP-42 with a web camera.

• 한국도로학회논문집
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• 제19권1호
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• pp.11-19
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• 2017

PURPOSES : The purpose of this study is to verify the property of self-healing, and to propose an appropriate duration for wet curing of bridge deck concrete overlays. METHODS : In this study, reinforced bars were inserted into concrete molds in order to prevent brittle fracture and induced cracks in the concrete resulting from indirect tension mode. The induced time of concrete cracking was 3 to 7 days, following which the concrete specimens were cured in water. The resulting concrete crack width was measured using image analysis equipment. Additionally, the self-healing tests were performed using the following three mixtures: OPC, SFC, and LMC. RESULTS : Concrete mixtures with crack widths of $150{\mu}m$ or lower were completely healed by Day 28. Hydrates of crack fills were found to be the calcium carbonate. CONCLUSIONS : The cement-based mixtures exhibit properties of self-healing. Considering these properties, it is necessary to increase the curing duration of concrete overlays for bridge decks.

• 콘크리트학회논문집
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• 제12권6호
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• pp.13-22
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• 2000

In order to resolve the problem of increasing traffic entailed by the economic development, road system is reorganization and new highways are built, and long span bridges over 40m are being constructed in environmental and aesthetic considerations. Most long span bridges that are currently being constructed are in general steel box girder and preflex girder bridges; however these types of breiges are less efficiency than PSC I-type girder bridges in terms of construction cost and maintenance. Therefore, in these study, structural efficiency of PSC I-type girders based on section parameters, concrete compressive strength and other design parameter is observed to develope new PSC I-type girder for long span bridges. As a results of analysis, most important design parameters that control the stress of the girder are found to be the top flange width and the height of girder. In this light, the relationship between the two variables is determined and cross-section details of the girder that most appropriates for the long span bridges are proposed. The use of high strength concrete appears to increase the general design span however the increase rate of the span from increasing concrete ultimate strength appears to be reduced depending on the span. Also, the optimal girder spacing is determined through the parameter studies of design span using the proposed girder.

• Journal of Biosystems Engineering
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• 제42권1호
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• pp.12-22
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• 2017

Purpose: This aim of this study was to develop a pick-up type pulse crop harvester for harvesting cut and dried pulse crop. Methods: The pick-up type pulse crop harvester was designed and constructed. Its specifications and operating performance were investigated. Results: Compared with conventional bean harvesters, the pick-up type pulse crop harvester adopted seven rows of chains with tines to pick-up the cut and dried pulse crop on a flat or ridged field, two transverse threshing drums with steel wire teeth to reduce the threshing speed, and a tilt plate and plastic bucket elevator for conveying clean grain to reduce damage. The threshing speed and the oscillating frequency of the separating and cleaning parts according to crop type and condition could be varied easily to efficiently use engine power and to improve harvesting performance. The harvester showed forward speed ranges of 0 ~ 1.5 m/s during harvesting operation, and 0 ~ 2.5 m/s during road travelling. The pick-up width of the harvester was about 1 m. Conclusions: The pick-up type self-propelled 51.5 kW harvester was designed and constructed to harvest cut and dried pulse crop. The effective field capacity of the harvester was predicted as above 40 a/h.

• 상하수도학회지
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• 제25권2호
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• pp.141-152
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• 2011

In this study, we extracted effective factors of pipe burst from the status data of water asset, operating data of pressure, volume and etc. and 7 years' pipe burst and repair records. The extracted factors were sorted by each attribution and then a statistical analysis was performed to generate a pipe burst probability function using the logistic regression model. As the result, material, diameter, length, laying year, pressure and road width affected to pipe burst significantly. Especially, in case of small diameter, laying year was most effective factor and in case of steel pipe, external loading was main cause of burst, and in case of cast iron, PE, PC, HP pipes, the deterioration of joint was main cause. The other side, as a result of Hosmer-Lemeshow goodness of fit test the models are turned out significant statistically. Also the classification criteria were determined to minimize the total cost from classification errors, when the predicted probability was more than 18% this pipe could have a chance of burst.

• 한국도로학회논문집
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• 제15권2호
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• pp.121-129
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• 2013

PURPOSES : This study deals with the traffic accidents of rotary in Korea. The objective of this study is to develop the accident models by age group based on the various data of rotaries. METHODS : In pursuing the above, this study gives particular attentions to classifying the accident data of 17 rotaries by age, collecting the data of geometric structure, traffic volume and others, and developing the models using SPSS 17.0 and EXCEL. RESULTS : First, 3 multiple linear regression models which were all statistically significant were developed. The value of model of under 30-49 age group were, however, evaluated to be 0.688 and be less than those of other models. Second, the most powerful variables were analyzed to be traffic volume in the model of under 30 age group, circulatory roadway width in the model of 30-49 age group, and the number of approach lane in the model of above 50 age group. Finally, the test results of accident models using RMSE were all evaluated to be fitted to the given data. CONCLUSIONS : This study propose install streetlights, speed humps and widen Circulatory as effective improvements for reduction of accident in rotary.

• 한국디지털건축인테리어학회논문집
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• 제10권1호
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• pp.65-74
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• 2010

This study has been given careful consideration to an induction of the mixed-use districts for the efficiency of Land Use, the rational plot planning and the mixture/complex among the functions in order to complement the zoning plan with the primary purpose to purify the usage of landscape. Furthermore, it is aimed to indicate the implementations through the medium of the in-depth analysis about the cardinal factors such as the standards on the regional location, building size and building uses in the case of designating the Mixed-use districts.Abstract This study has been examined by the aspect of scope for securing the adequacy of Site Division Restriction, Floor Area Ratio, Building Coverage Ratio and Outdoor Area Ratio in the "Mixed-Use Districts" and especially, by the medium of the in-depth analysis about the actual condition of building and outdoor space scales. It has been deduced the scale standards by using the simulation and correlation analysis among the factors of those buildings and outdoor spaces. Moreover, it has been applied the analysis method of using the building scale, especially, the latter has analyzed the total 1,656 different types classified by 3 patterns of Plottage and Building Coverage Ratio, 9 patterns of the factor change on Outdoor Area Ratio and 8 different patterns of road width.

• 한국주거학회논문집
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• 제19권6호
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• pp.85-93
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• 2008

This study analyzes areas, traffic lines and characteristics of block of traditional villages in order to suggest how to build urban village in the way that can solve problems occurring in residential areas these days. The study showed the following results: 1) Traditional villages have definite boundary and entrance, and the community area for the villages is close to the entrance to encourage community activities of villagers. 2) With an access in the form of a blind alley branched from the main road, traditional villages form a small-sized clustering and encourage community activities in a natural way. 3) Formed of block with a pattern of net, blind alley or standing in a line on both sides, traditional villages help residents to form close relations between. These findings suggest that for building desirable urban villages, 1) they should have definite boundary, 2) size and location of community area should be determined in the way to activate community activities of residents, 3) roads inside the village should have branched form rather than standardized check pattern so that small-sized clustering could be formed along the branched inner roads, and 4) clustering in villages should be arranged in a line on both sides or in the form of a blind alley giving consideration to the length and width of roads. The roads should be also of a closed type so that residents could create strong bonds with their neighbors.

• Wind and Structures
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• 제14권1호
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• pp.55-70
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• 2011

This study investigates the design criteria required for wind barriers to protect vehicles running on an expressway under a high side wind. At the first stage of this study, the lateral deviations of vehicles in crosswinds were computed from the commercial software, CarSim and TruckSim, and the critical wind speeds for a car accident were then evaluated from a predefined car accident index. The critical wind speeds for driving stability were found to be 35 m/s for a small passenger car, yet 30 m/s for a truck and a bus. From the wind tunnel tests, the minimum height of a wind barrier required to reduce the wind speed by 50% was found to be 12.5% of the road width. In the case of parallel bridges, the placement of two edge wind barriers plus one wind barrier at center was recommended for a separation distance larger than 20 m (four lanes) and 10 m (six lanes) respectively, otherwise two wind barriers were recommended.