• Journal of Korean Society of Transportation
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• v.31 no.5
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• pp.60-70
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• 2013

This study aims to develop a truck priority on left-turn algorithm that can reduce greenhouse gas emissions by reducing heavy duty truck's stops at signalized intersection. The signal priority is granted for a left-turn phase, because heavy duty trucks can deteriorate left-turn traffic flow due to the low acceleration or deceleration rate and large turn radius. Truck priority allows to provide the stable speed control for heavy duty truck, and reduces emissions at the signal intersection. Also, two signal recovery strategies are compared for various traffic conditions. This study analyzes the effectiveness of truck priority such as greenhouse gas emissions and fuel consumption reduction, and total travel time saving using the PARAMICS and Comprehensive Modal Emissions Model (CMEM). The results show that signal priority for heavy duty trucks has an effect on reducing greenhouse gas emissions and fuel consumptions at non-peak hour. Also, it shows decreasing total travel time due to reducing truck stops.

• Journal of the Korean Operations Research and Management Science Society
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• v.35 no.2
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• pp.1-17
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• 2010

This paper aims to compare four operating priority rules of RMGC (Rail Mounted Gantry Crane) used in semi-automated container terminal. The four priority rules employed in this paper are FCFS (First-come-first-served), LCFS (Last-come-first-served), TOS (Turn-over-served) and NFS (Nearest-first-served). And to compare the four operating priority rules, this paper analyzed productivity of RMGC and CC (Container Crane), waiting time of YT (Yard Truck) and RT (Road Truck) in container yard, and turnaround time of RT in container terminal of each priority rule by using stevedoring simulation. As a result, NFS was evaluated as the best rule to improve the overall productivity of container terminal in terms of all criteria.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.2
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• pp.13-22
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• 2017

The present study proposes a new methodology for predicting the demand for truck rest areas beside national highways. Previous demand forecasting methods were reviewed first in order to complement them with additional items. The results of the study are as follows. In the demand forecasting process, the primary task is to divide parking demands of trucks into short-term parking and long-term parking. Since short-term and long-term parking vary in utilization, congestion, and turnover rate, different influence factors should be considered according to parking time. Furthermore, the demand characteristics of rest and convenience facilities need to be reflected as well, because they in turn affect the demand for truck rest areas. In sum, the demand forecasting process for destination-type truck rest areas on national highways requires more attention than that for truck rest areas on expressways, and possible influences of various factors should be examined in this process.

• Journal of Korean Port Research
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• v.14 no.1
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• pp.13-26
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• 2000

In this paper, we compare and analyze the current state of the productivity of the stevedoring work among several container terminals in 1999. Based on these results of analysis, we firstly classify several factors which impede the efficient operations of container terminal as follows ; late arrival of container beyond cargo closing time(CCT), change of port of destination, change of vessel, and return cargo. Such factors are major cause for the cargo rehandling on terminals, thus deteriorate the overall performance of transfer crane during the stevedoring work. In order to improve the productivity of container terminal, we suggest that it is necessary for establishing and operating the efficient logistics management system. Especially, we emphasize the importance of information exchange on the scheduled cargoes among the relevant parties such as shippers, shipping companies, and terminal operators, which is the most effective way to alleviate the cargo rehandling.

• International Journal of Highway Engineering
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• v.15 no.5
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• pp.111-122
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• 2013

PURPOSES : The purpose of this system (Rear Lighting System) is to provide illumination for the driver to operate the commercial vehicle safely after dark in highway, to increase the conspicuity of the vehicle, and especially be suggesting the finest observable improvement method, depending on color and pattern of rear lighting system of truck for midnight highway traffic. METHODS : Rear lightning system as an improving way for forward commercial vehicles lighting the securing sight from human factors and the surrounding environment in midnight driving. For this one, basic materials were collected from the data analysis about many types of problems, and filed investigation for establishing Driving Simulator. also taking statistic test to human volunteers after finding recognizable distance of them. RESULTS : As a result, color with the highest visuality is amber followed by green-red-blue as in order for all road types. Especially almost no difference is found between red and green, also when the light is turn off, recognizable distances is wide difference compared to turn on the light. One more thing about study per pattern, upper and entire lighting have similar recognizable distances, but under lighting shows short distance with difficulty securing sight from medians. And straight section shows similar recognizable distances. By finding visuality improvement method depending on color and pattern of supplement taillight, it is expected to suggest quantitative judgement standard for introducing regulation and improvement of supplement taillight. CONCLUSIONS : Night time vehicle conspicuity to the rear is provided by rear position lamps. this study is showed that the color of light ramp is not important to be safe driving, most important is to turn on the light, recognizable distances is big different compared to turn off the rear light, so when the drivng dark in highway, have to turn on the light for reducing risk.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.40
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• pp.147-167
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• 2008

This paper investigates changing business transaction under the e-commerce environment and their implications on freight transport industry with some case studies. It shows that an efficient and reliable delivery system is essential for e-commerce as business industries are faced with the stricter and more diversified demands of customer. In addition, many aspects of business practices such as small batch, customized production and just-in-time distribution in the e-commerce environment, in turn, bring about a number of changes in the volume and service patterns of freight transport. E-commerce requires longer transport distances and often higher delivery frequencies. It also entails to a certain extent a modal shift towards truck and air freight transport modes. On the one hand, the logistical requirements of e-commerce goods may stimulate greater complexity in existing supply chain management, causing higher costs. However it is true that the increased visibility of goods through more efficient information flow allows more efficient and effective transport management in the logistics system.

• International Journal of Highway Engineering
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• v.14 no.6
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• pp.159-165
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• 2012

PURPOSES : The lack of details of guidelines on how to install the Chicane for traffic calming leads the practical difference across the calming areas, so the benefits expected from these facilities are not hardly observed. In this context, this study analysed the relationship between the geometric design alternatives of Chicane with the dynamic behaviour of vehicles in terms of speed and trajectory. METHODS : The study analysed vehicle dynamic behaviour using dynamic analysis program Auto-Turn under various geometric conditions of Chicane. RESULTS : This study suggested the design alternatives of Chicane using terms such as "longitudinal displacement value", "lateral displacement value", etc. which are defined in the study. The suggested combination set is fulfilling the desired or target speed of vehicles and clearance between vehicle and roadside at the same time. CONCLUSIONS : The results from this study can be applied to install Chicane corresponding to the local condition where target speed is 30km/h. The study showed the design alternatives of chicane corresponding to the given road cross-sectional design and clearance to roadside for passenger cars and light truck respectively.

• Journal of KIBIM
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• v.12 no.4
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• pp.61-69
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• 2022

Earthmoving operations account for approximately 25% of construction cost, generally executed prior to the construction of buildings and structures with heavy equipment. For the successful completion of earthwork projects, it is crucial to constantly monitor earthwork equipment (e.g., trucks), estimate productivity, and optimize the construction process and equipment on a construction site. Traditional methods however require time-consuming and painstaking tasks for the manual observations of the ongoing field operations. This study proposed the use of a GPS sensor embedded in a smartphone for the tracking and visualization of equipment locations, which are in turn used for the estimation and simulation of cycle times and production rates of ongoing earthwork. This approach is implemented into a digital platform enabling real-time data collection and simulation, particularly in a 2D (e.g., maps) or 3D (e.g., point clouds) virtual environment where the spatial and temporal flows of trucks are visualized. In the case study, the digital platform is applied for an earthmoving operation at the site development work of commercial factories. The results demonstrate that the production rates of various equipment usage scenarios (e.g., the different numbers of trucks) can be estimated through simulation, and then, the optimal number of tucks for the equipment fleet can be determined, thus supporting the practical potential of real-time sensing and simulation for onsite equipment management.