• Journal of Korean Society of Transportation
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• v.26 no.2
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• pp.57-67
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• 2008

Loading zone is necessary to central business district(CBD) due to freight trucks coming into inner city. Currently truck drivers in metropolitan area are forced to illegally park their freight trucks on the roads close to the business facilities because there is no or few loading zones available in the CBD. This situation would bring into traffic congestion and even might block local roads in the CBD. This study reviews the existing improvement plans in city logistics, and examines delivery characteristics related to freight trucks and drivers in Seomyeon, the central downtown of Busan. Also it conducts a location planning for on-street loading/unloading bay using a technical method for arranging loading space. This research estimated the number of parking and stop bays for truck's operation using queueing theory based on truck-service rate and arrival rate, and found locations with the minimum resistance function values for freight movement in arranging on-street loading/unloading bays.

• Journal of the Korean Society for Heat Treatment
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• v.12 no.4
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• pp.303-312
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• 1999

An investigation of the CrMoV rotor steel weldment which experienced by cyclic thermal aging heat treatment and as-received condition was performed. This evaluation was carried out to confirm whether this type of weldment is appropriate for the service environment in terms of microstructural examinations, microhardness measurements and tensile tests. The cyclic thermal aging heat treatment, containing continuous heating and cooling thermal cycle was programmed to simulate the real rotor service condition. The heat treatment was performed for 40 cycles(5920hrs). The results indicated that the weldment was composed of 4 different regions such as heat affected zone of the base metal, butter weld(initial weld), full thickness weld(final weld) and the base metal. The double welding process was applied to eliminate the susceptibility of reheat cracking at heat affected zone of base metal. The grain refinement at the HAZ due to the welding process could reduce the possibility of cracking susceptibility, but its tensile properties was appeared to be low due to the weld metal in as-received condition. The benefit effect, grain refinement was extended with carbides coarsening during the cyclic thermal aging heat treatment. However the poor mechanical properties of the weldment was more degraded as undergoing the heat treatment.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.13 no.4
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• pp.57-62
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• 2014

Recently, research activities to develop services for providing safety information to the drivers in fast moving vehicles based on various wireless network technologies such as DSRC (Dedicated Short Range Communication), IEEE 802.11p WAVE (Wireless Access for Vehicular Environment) are widely being carried out. This paper presents a proof-of-concept model based on a robot-car for Dilemma Zone Decision Assistant Service using the wireless LAN technology. The proposed model system consists of a robot-car based on an embedded Linux OS equipped with a WiFi interface and an on-board unit emulator, an Android-based remote controller to model a human driver interface, a laptop computer to run a model traffic signal controller and signal lights, and a WiFi access point to model a road-side unit.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.5
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• pp.26-37
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• 2009

This paper suggests a sensor's placement method for detecting the dilemma zone problem when real-time driver's safety service is provided at signalized intersections by multiple pointed traffic sensors using USN environments. For detecting the dangerous situations from vehicles accelerating through yellow intervals, red-light running and stopping abruptly like as dilemma zone problem, VISSIM(microscopic, behavior-based multi-purpose traffic simulation program) is used to perform a real-time multiple detection situation by changing the input data like as various inflow-volume, design speed change, driver perception and response time. As a result, the optimal interval of traffic sensors is 20~27m, and the initialized sensor location from stop-line is different according to road design speed. Moreover, the pattern of detection about dilemma zone is also different according to inflow-volumes. This paper shows that the method is useful to evaluate the sensor's placement problem based on micro-simulation and the results can be used as the basic research for USN services.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.8
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• pp.1248-1254
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• 2022

Efforts are being made to prevent traffic accidents in the school zone in advance. However, traffic accidents in school zones continue to occur. If the driver can know the situation information in the child protection area in advance, accidents can be reduced. In this paper, we design a camera that eliminates blind spots in school zones and a number recognition camera system that can collect pre-traffic information. It is designed by improving the LIDAR system that recognizes vehicle speed and pedestrians. It collects and processes pedestrian and vehicle image information recognized by cameras and LIDAR, and applies artificial intelligence time series analysis and artificial intelligence algorithms. The artificial intelligence traffic accident prevention system learned by deep learning proposed in this paper provides a forced push service that delivers school zone information to the driver to the mobile device in the vehicle before entering the school zone. In addition, school zone traffic information is provided as an alarm on the LED signboard.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.6
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• pp.46-60
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• 2023

This study examines the appropriateness of indicators and methodologies through the evaluation of cultural services in border areas and uses them as basic data for the ecosystem service-based management of border areas, which are key domestic ecological assets. Accordingly, in this study, seven border cities and counties were evaluated and compared based on the evaluation indicators and methods presented by the National Institute of Ecology. As a result of the cultural service evaluation, it was found that Paju City was superior in leisure and tourism, Inje-gun was best in scenic beauty and heritage, and Yanggu-gun was strongest in education, and Inje-gun in heritage. Accordingly, through this study, future tasks for comprehensive cultural service evaluation were presented as follows. First, in order to evaluate ecosystem services at the national and regional levels, it is necessary to establish an indicator system for cultural service evaluation and monitoring. Second, when building a cultural service evaluation index system, it is necessary to review upper and lower conceptual units and the consistency between indicators according to the scale of the evaluation region. Third, a specific review of DB utilization for cultural service evaluation should be conducted depending on the type of ecosystem. Lastly, given the significant lack of domestic cultural service research, additional basic research must be conducted to evaluate cultural services including non-material and qualitative perceptions. In order to evaluate cultural services in the future, additional basic research is needed for each ecosystem type, and a process of finding appropriate evaluation indicators and methods through research is necessary.

• Journal of the military operations research society of Korea
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• v.2 no.1
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• pp.177-184
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• 1976

As the organizational size of a military service or business increases and its management becomes complex, the success in its management depends less on static type of management but more on careful, dynamic type of management. In this thesis, an operations research technique is applied to the problems of determining optimal air traffic control rule and of optimal capacity of air base for a military air base. An airport runway is regarded as the service facility in a queueing mechanism, used by landing, low approach, and departing aircraft. The usual order of service gives priority different classes of aircraft such as landings, departures, and low approaches; here service disciplines are considered assigning priorities to different classes of aricraft grouped according to required runway time. Several such priority rules are compared by means of a steady-state queueing model with non-preemptive priorities. From the survey conducted for the thesis development, it was found that the flight pattern such as departure, law approach, and landing within a control zone, follows a Poisson distribution and the service time follows an Erlang distribution. In the problem of choosing the optimal air traffic control rule, the control rule of giving service priority to the aircraft with a minimum average waiting cost, regardless of flight patterns, was found to be the optimal one. Through a simulation with data collected at K-O O Air Base, the optimal take-off interval and the optimal capacity of aircraft to be employed were determined.

• Computers and Concrete
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• v.15 no.4
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• pp.589-606
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• 2015

It is well-documented that the major deterioration of coastal RC structures is chloride-induced corrosion. Therefore, regional investigations are necessary for durability based design and evaluation of the proposed service life prdiction models. In this paper, four reinforced concrete jetties exposed to severe marine environment were monitored to assess the long term chloride penetration at 6 months to 96 months. Also, some accelerated durability tests were performed on standard samples in laboratory. As a result, two time-dependent equations are proposed for basic parameters of chloride diffusion into concrete and then the corrosion initiation time is estimated by a developed probabilistic service life model Also, two famous service life prediction models are compared using chloride profiles obtained from structures after about 40 years in the tidal exposure conditions. The results confirm that the influence of concrete quality on diffusion coefficients is related to the concrete pore structure and the time dependence is due to chemical reactions of sea water ions with hydration products which lead a reduction in pore structure. Also, proper attention to the durability properties of concrete may extend the service life of marine structures greater than fifty years, even in harsh environments.

• Asia pacific journal of information systems
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• v.34 no.1
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• pp.1-25
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• 2024

Consumer demand for e-commerce services has skyrocketed due to the introduction of social distancing standards and lockdown measures that countries have taken to combat the pandemic. There has been a notable surge in the popularity of on-demand delivery services, with a significant influx of new users turning to the e-platform for assistance. This research paper tries to identify the enablers of E-commerce Utility and Service Quality and establish a connection using total interpretive structural modelling (TISM). Enablers are the building blocks for providing customers with an enhanced and more consistent service experience contributing to service quality. The enablers and the linkages thus established hold valuable insights for e-commerce marketers, aiding them in effectively reaching their customers, and achieving desired growth outcomes. The TISM- based model and the MICMAC analysis identified two barriers; website design and personalization as the decisive attributes of e-commerce service quality, possessing strong driving power and weak dependence. Furthermore, the factors of reliability, responsiveness, information, and ease of use form the linkage zone, indicating that any action taken on these factors would not only influence other factors but also have a reciprocal effect on them.

• Steel and Composite Structures
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• v.28 no.3
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• pp.267-278
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• 2018

Structures may need retrofitting as a result of design and calculation errors, lack of proper implementation, post-construction change in use, damages due to accidental loads, corrosion and changes introduced in new editions of construction codes. Retrofitting helps to compensate weakness and increase the service life. Fiber Reinforced Polymer (FRP) is a modern material for retrofitting steel elements. This study aims to investigate the effect of deficiency location on the axial behavior of compressive elements of Circular Hollow Section (CHS) steel short columns. The deficiencies located vertically or horizontally at the middle or bottom of the element. A total of 43 control column and those with deficiencies were investigated in the ABAQUS software. Only 9 of them tested in the laboratory. The results indicated that the deficiencies had a significant effect on the increase in axial deformation, rupture in deficiency zone (local buckling), and decrease in ductility and bearing capacity. The damages of steel columns were responsible for resistance and stiffness drop at deficiency zone. Horizontal deficiency at the middle and vertical deficiency at the bottom of the steel columns were found to be the most critical. Using Carbon Fiber Reinforced Polymer (CFRP) as the most effective material in retrofitting the damaged columns, significantly helped the increase in resistance and rupture control around the deficiency zone.