• Journal of Korean Society of Transportation
• /
• v.31 no.1
• /
• pp.15-24
• /
• 2013

To accommodate urban concentration of population, multi-purpose super-tall buildings have been introduced, but they induce many travel demands causing regional traffic problems. While several travel demand management policies such as transit promotion or parking limits are presented to alleviate such problems, transportation infrastructure are still insufficient to meet high demands. In this study, super-tall buildings are categorized by scale and purpose, then mode-specific derived demand is estimated using modal share of each category. Optimal transportation infrastructure level is determined by condition-based average changing amount yielded by street network delay (in case of road) or the number of transit routes (in case of transit).

• Journal of Korean Society of Transportation
• /
• v.30 no.2
• /
• pp.127-136
• /
• 2012

Multi-car rear-end collision accidents have three categories: sequential collision from the rear which is commonly referred to as chain reaction collision, sequential collision from the front, and mixed-order collision. This paper suggests several effective methods of reconstruction analysis for multi-car rear-end collision accidents. First, by incorporating the traditional empirical method which uses vehicle damage caused by brake dive and passenger injuries, with results of theoretical analysis made within mechanics of rigid body, it is made possible for the method to be put to immediate practical use. A methodology to precisely analyze multi-car rear-end collision accidents was suggested using a simulation program simultaneously with a video event data recorder which is starting to be widely used in domestic vehicles. To go beyond the simple intuitive analysis of the video event data recorder, the simulation analysis based on the results of video analysis was executed to acquire various information, so that the causes and responsibility could be clearly stated.

• ETRI Journal
• /
• v.30 no.5
• /
• pp.663-673
• /
• 2008

The multi-scenario topology of multi-channel hybrid ubiquitous sensor networks (USNs) is studied and a novel link auto-diversity cross-layer cooperative scheduling scheme is proposed in this paper. The proposed scheme integrates the attributes of the new performance evaluation link auto-diversity air-time metric and the topology space in the given multi-scenario. The proposed scheme is compared with other schemes, and its superiority is demonstrated through simulations. The simulation results show that relative energy consumption, link reception probability, and end-to-end blocking probability are improved. The addressing ratio of success with unchanged parameters and external information can be increased. The network can tolerate more hops to support reliable transportation when the proposed scheme is implemented. Moreover, the scheme can make the network stable. Therefore, the proposed scheme can enhance the average rate performance of the hybrid USN and stabilize the outage probability.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2001.04a
• /
• pp.631-634
• /
• 2001

In this study, the graphic simulation system of multi joint manipulator is developed to analyze and optimize the remote handling processes for the spent fuel assembly. This system consists of a 3-D graphical modeling system, a device assembling system, and a motion simulation system. To analyze and optimize the processes involved in multi-joint manipulator operation such as NFBC transportation process and bottom nozzle removal process, the virtual work place is implemented using a computer graphic technology. This virtual workcell is exactly same as that of the real environment. This graphic simulation system of the multi-joint manipulator can be effectively used for designing the main processes and maintenance processes of the spent fuel management.

• Journal of the Korea Society for Simulation
• /
• v.10 no.1
• /
• pp.35-50
• /
• 2001

Managing multi-echelon inventory systems has gained importance over the last decade mainly because integrated control of supply chains consisting of several processing and distribution stages has become feasible through modern information technology. Determination of optimal inventory policy for multi-echelon supply chain is made difficult by the complex interaction between the different levels. In this paper, we investigate performance of five inventory policies (fixed quantity order policy, fixed interval order policy, compromised order policy, lead time-fixed quantity order policy, and mixed order policy) in a multi-echelon supply chain by using a simulation model constructed with AweSim simulation language. The results of the simulation study show that the mixed order policy is the best among five inventory policies in the most test problems except the case when the stockout cost per unit is much higher than the inventory holding and transportation costs per unit.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.64 no.2
• /
• pp.324-330
• /
• 2015

Energy Saving Methods in existing railway vehicle are considered by active approach such as regenerative energy storage and utilization, eco driving, etc. On the other hands, energy saving measures in railway station are operated by passive method such as reduction of operating time in ventilation system, cooing system and power equipment. To reduce energy and for independence in railway system, it requires an active energy saving measures. It needs to its own power source besides the power source of electric supply company such as renewable energy and regenerative energy and take the advantage of power storage system and stored power are used in optimum time. This paper deal with 3-level NPC inverter and T-type NPC inverter that used in various multi-level topology applicable to the railway system.

• Korean Institute of Interior Design Journal
• /
• v.22 no.5
• /
• pp.344-356
• /
• 2013

Due to implementation of legislations for translation poor such as handicapped people, elderlies, children most public buildings are now integrating barrier free design methods. However, barrier free design is still considered as constraints of physical elements that only serve to meet functional aspects for minors and conflict with designs of the space. The authors believe that it is time that barrier free design is considered not as constraints but opportunities that both meet functional and aesthetical needs serving the growing population of transportation poor and others as well. This paper has looked into characteristics of transportation poor and barrier free design elements of passenger terminals and developed 4 categories of design methods. applied by using human sense, form, furniture, and architectural elements. Then the authors analyzed Gunsan International and coastal passenger terminal existing conditions which is considered to be designed to meet barrier free guidelines and legislations through the developed design categories and elements. The result turned out that the subject in regard of barrier free designs for transportation poor lack various applications such as forms that can be used as symbolic and directional elements that assists as wayfinding cues. Also, flexible and multi functional approaches in furniture arrangements, structural approaches are needed.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.10 no.1
• /
• pp.69-82
• /
• 2002

Recently, it appears that the major change in open skies agreement established the bilateral agreement and sub-regional multi-lateral agreement system with U.S.A. as the central figure. Specifically sub-regional multi-lateral air transportation cooperation is based on the bilateral agreement systems among the like minded countries. To develop the air transportation industry, Each country tries to come true free air transportation in bloc and deregulation in terms of market approach and traffic right. The purpose of this study is to look into the background of sub-regional air transportation cooperation and to expect the economic impact of the open skies agreement. We selected the Singapore in Asia-Pacific region as the subject of investigation. Even though Singapore is a small country in Asia-Pacific region. They have global competition power which is airport field as well as to airlines and tourism industry. Under this condition, we analyzed the economic impact of the open skies policy through the Input/Output analysis.

• Smart Structures and Systems
• /
• v.8 no.4
• /
• pp.413-431
• /
• 2011

Under the external shearing stress, the external radial stress and the electric potential simultaneously, the piezoelectric hollow cylinder transducer is studied. With the Airy stress function method, the analytical solutions of this transducer are obtained based on the theory of piezo-elasticity. The solutions are compared with the finite element results of Ansys and a good agreement is found. Inherent properties of this piezoelectric cylinder transducer are presented and discussed. It is very helpful for the design of the bearing controllers.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2003.11a
• /
• pp.549-552
• /
• 2003

User's demand, as a maintenance for durability of construction and a comfortable life, and an incentive systems for new waterproofing system incite waterproofing company to evolve new waterproofing system that is upgraded waterproofing quality by getting advantages for the existing waterproofing systems. There are seven new waterproofing systems for building roof to be authorized from Ministry of construction & transportation. Those are multi-layers waterproofing system, and five of those are the insulation type. A trend of new waterproofing systems for building roof is multi-layers waterproofing system insulated.