• International conference on construction engineering and project management
• /
• 2013.01a
• /
• pp.507-508
• /
• 2013

International Roughness Index (IRI) has been widely used by state DOTs to quantify pavement smoothness. When pavement condition falls below certain IRI thresholds, corresponding pavement maintenance treatments should be considered for application. Selection of appropriate IRI thresholds is essential to tactical allocation of limited resources to improve the conditions of states' roadway systems. This selection process is often challenging, however, because IRI thresholds are largely determined by Perceived Ride Quality (PRQ), and PRQ differs in each state. In this paper, a framework is proposed to address this problem. Passenger raters will be randomly selected from predetermined geographic locations, and their PRQ ratings collected. Taking this perceived ride data, along with other data collected, a statistical analysis will be conducted to establish the relationship between measured IRI values and PRQ. Appropriate IRI thresholds will then be determined. Once this framework is implemented, state DOTs could make informative maintenance decisions, which are expected to greatly enhance the public perception of pavement conditions in today's challenging economy.

• Journal of Korean Society of Transportation
• /
• v.19 no.6
• /
• pp.7-17
• /
• 2001

The purpose of this paper is to develop automatic incident detection algorithm using image based detector in freeway management system. This algorithm was developed by using neutral network for high speed roadway and by using speed and occupancy variable for low speed roadway. The image detector system with the developed automatic incident detection algorithm can detect multi-lane as well as several detect areas for each lane. To evaluate this system, field tests to measure the detecting rate of incidents were performed with other systems which have APID and DES algorithm at high speed roadway(freeway) and low speed roadway(national arterial). As the results of field test, it found that the detect rate of this system was highest rate comparing to other two systems.

• Journal of the Society of Disaster Information
• /
• v.13 no.2
• /
• pp.199-212
• /
• 2017

Rapid roadway snow removal is significantly important due to difficult occurrence estimation of heavy snowfall disasters by global warming and climate change. Local governments of S. Korea have snow removal equipments and vehicles based on past experiences without considering snowfall and roadway characteristics. The objective of this research is to develop the demand estimation procedure for snow removal equipments and vehicles based on regional snowfall and roadway characteristics. This research first classifies regional snowfall characteristics using KMO's ten-year snowfall data. Second, roadway snow removal length is computed for local governments. Real possession data is compared with demand estimation of snow removal equipments & vehicles for each local government with roadway snow removal scenarios. Finally, required demands of snow removal equipments & vehicles are predicted by concerning regional snowfall amount and required snow removal hours. Results from this research are used for developing heavy snowfall disaster management policies for optimal demands and snow removal routes of 229 local governments.

• 한국ITS학회:학술대회논문집
• /
• 2008.11a
• /
• pp.309-310
• /
• 2008

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2014.06a
• /
• pp.223-224
• /
• 2014

Along with container freights keep increasing globally, lots of containers used for inland distribution increase steadily too. In Korea, there are many modes to transfer container freights such as roadway, railroad, coastal shipment. The roadway transportation is the most common but it is considered as the most inefficient mode. This paper studies about reasons that affect to the inefficiency of roadway transport and finds solution to resolve the problem. First backhaul transportation is addressed and some suggested solutions are presented such as construction of inland inspection center or managing efficiently container management. Then mathematical model is used to show the quantitative evaluation of backhaul transport solution.

• Korean Journal of Construction Engineering and Management
• /
• v.14 no.6
• /
• pp.14-21
• /
• 2013

While a detailed cost estimation utilizes the comprehensive quantity information obtained from a complete drawing and specification, an approximate cost estimation heavily relies on the subjective decisions. This phenomenon is because the approximate estimation is usually conducted in early stage of the construction phase where the drawing and specification are not available. This study developed a roadway construction cost estimation system which enables users to estimate the approximated cost of the project in early stage. The system identifies the variation of the construction costs due to the road route change using a cased based reasoning(CBR) method. Overall the system is expected to improves the accuracy and effectiveness of the estimation process, because it would provide users with increased accessability and consistent results in early stage of the project which leaded to the increased work transparency.

• Proceedings of the KSR Conference
• /
• 2008.06a
• /
• pp.118-121
• /
• 2008

Bimodal tram is a transit with no-step floor for wheel-chaired persons, with docking to the station precisely and moving on schedule like train. Because of the automatic traveling of bimodal tram to search and follow the magnet embedded in roadway, bimodal tram should be careful about rainfall, snow and wind like a car driving on roadway in respect to natural disasters. Though response procedures in emergency are different according to the passengers' boarding, emergency mobilization is needed if any emergency situation happens. Emergency mobilization is the act of preparing for major catastrophic events, which may affect public transportation systems or their service areas, by assembling and organizing resources, including people, equipment, facilities, communications systems, expert technical support, and public information systems and protocols. Mobilization is the process that ensures that the right people will deploy appropriate resources at the correct time. Effective mobilization requires a partnership of local and state agencies. Public transportation operators and systems play vital roles in response to and recovery from emergencies and other unexpected catastrophic events. These systems, and their capabilities to mobilize resources, are profoundly affected by the decisions and directives of others during these activities. In this study, we focused on the emergency management for bimodal tram and reviewed the considerations about infrastructures under natural disasters, especially heavy rainfall.

• Journal of Korean Society of Transportation
• /
• v.17 no.1
• /
• pp.173-185
• /
• 1999

The purpose of this study is to develope a forecasting model to implement short-term Congestion Management Program (CMP) based on TDM strategies in Seoul. The CMP is composed of three elements: 1) setting a goal of short-term traffic management. 2) developing a model to forecast the impacts of TDM alternatives, and 3) finding TDM measures to achieve the goal To Predict the impacts of TDM alternatives, a model called SECOMM (SEoul COngestion Management Model) is developed. The model assumes that trip generation and distribution are not changing in a short term, and that only mode split and traffic assignment are affected by TDM. The model includes the parameter values calibrated by a discrete mode choice model, and roadway and transit networks with 1,020 zones. As a TDM measure implement, it affects mode choice behavior first and then the speeds of roadway network. The chanced speed again affects the mode choice behavior and the roadway speeds. These steps continue until the network is equilibrated. The study recommends that CMP be introduced in Seoul, and that road way conditions be monitored regularly to secure the prediction accuracy of SECOMM. Also, TDM should be the major Policy tools in removing short-term congestion problems in a big city.

• International Journal of Highway Engineering
• /
• v.17 no.3
• /
• pp.1-12
• /
• 2015

PURPOSES : This paper presents a description of the current issues facing road managers regarding the surface-type conversion of low-volume roads for cost savings. METHODS: The paper reviews previous works conducted toward this end, acknowledges gaps in the current research, and lays out what information is needed for further studies. RESULTS : If the cost to maintain an unsurfaced road is less than the cost of maintaining a surfaced road, then there is potential for cost savings for the management agency. However, the problem is bigger than simply maintaining the roads that already exist. If unsurfaced roads prove to be more economical than surfaced roads, then the cost to convert from a surfaced to an unsurfaced roadway, and vice versa, when necessary, must also be examined. CONCLUSIONS : No other studies have addressed the un-surfacing of a road for cost savings, and it is therefore unknown whether substantial savings can be realistically obtained by converting from a surfaced to an unsurfaced road. To determine whether a conversion policy would be a viable option, additional data and research are needed.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.3 no.1 s.4
• /
• pp.45-52
• /
• 2004

There are many cities installing ITS(Intelligent Transportation Systems) and running TMC(Trafnc Management Center) to improve mobility and safety of roadway transportation by providing roadway information to drivers. There are many devices in ITS which collect real-time traffic data. We can obtain many valuable traffic data from the devices. But it's impossible to avoid missing traffic data for many reasons such as roadway condition, adversary weather, communication shutdown and problems of the devices itself. We couldn't do any secondary process such as travel time forecasting and other transportation related research due to the missing data. If we use the traffic data to produce AADT and DHV, essential data in roadway planning and design, We might get skewed data that could make big loss. Therefore, He study have explored some imputation techniques such as heuristic methods, regression model, EM algorithm and time-series analysis for the missing traffic volume data using some evaluating indices such as MAPE, RMSE, and Inequality coefficient. We could get the best result from time-series model generating 5.0$\%$, 0.03 and 110 as MAPE, Inequality coefficient and RMSE, respectively. Other techniques produce a little different results, but the results were very encouraging.