• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2011.05a
• /
• pp.141-143
• /
• 2011

A Study on the Curtain Wall parts that appear to cause problems and to improve information exchange system by applying the model of SOA-based development directions are suggested. Availability of the IT industry than other industries that have closed in the field of construction such as SOA. IT systems for the compatibility of the information being sought may be applied. In the future adoption of SOA and Web service-based approach to information exchange with suppliers and improving the efficiency of information for the construction to cover the entire field of research will be conducted as a SOA system.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.48 no.12
• /
• pp.709-714
• /
• 1999

This paper is focused on the adhesion control method to improve traction efficiency using the estimated adhesion for railway propulsion system. Recently, the wheel slippery is frequently occurred due to light weight of train and power increasement of traction parts. This phenomenon occurs a traction loss and a poor ride comport. Therefore, the adhesion control which is able to prevent the slippery and to control the traction on a maximum adhesion is absolutely needed. This paper introduces typical methods for adhesion control and proposes two novel adhesion methods using the estimated adhesion.

• The KIPS Transactions:PartA
• /
• v.18A no.2
• /
• pp.69-74
• /
• 2011

The minimum dominating set problem of a graph G is to find a smallest possible dominating set. The minimum dominating set problem is a well-known NP-complete problem such that it cannot be solved in polynomial time. Heuristic or approximation algorithm, however, will perform well in certain area of application. In this paper, we suggest three different simulated annealing algorithms and experimentally show better efficiency improvement by applying these algorithms to the graph instances developed by DIMACS.

• Proceedings of the KIPE Conference
• /
• 2007.07a
• /
• pp.172-174
• /
• 2007

The AC-DC Adapter has been widely used in Mobile Phones, Note Book PC, LCD monitors, and portable electronic products. Recently, high-power-density Adapter was developed. This adapter increases power factor using a bridge diode rectifier and PFC, however, there are weak points that improving efficiency is limited. In the bridgeless rectifier circuit proposed in this paper, there is no PFC, however, the power factor and efficiency are improved by BCM and ZCS operations.

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2006.09a
• /
• pp.597-598
• /
• 2006

Gas filtration at high temperature from industrial processes offers various advantages such as increasing process efficiency, improving heat recovery and materials resource recovery, etc. At the same time, it is an advanced environment protection technology. This paper describes a newly developed metallic filter element. The manufacturing process of sintered $Fe_3Al$ metallic powder and the mechanical and filtration characteristics of this filter element were investigated. In this work, the phase constituent changes of the $Fe_3Al$ powder during sintering were studied. The newly developed filter elements were found to have excellent corrosion resistance, good thermal resistance, high strength and high filtration efficiency.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.8 no.2
• /
• pp.57-63
• /
• 2000

This paper deals with a study on combustion and emission characteristics of a direct injection diesel engine dual fueled with natural gas. Dual fuelling systems tend to emit high unburned fuel especially at low load, resulting in a decreased thermal efficiency. This is because natural gas-air mixtures are too lean for flame to propagate under low load conditions. Suction air quantity and injection timing controls are very useful to improve emissions and thermal efficiency at low load.

• Industrial Engineering and Management Systems
• /
• v.11 no.1
• /
• pp.94-102
• /
• 2012

In this paper, an interactive planning and scheduling framework are proposed for optimising operations from pits to crushers in ore mining industry. Series of theoretical and practical operations research techniques are investigated to improve the overall efficiency of mining systems due to the facts that mining managers need to tackle optimisation problems within different horizons and with different levels of detail. Under this framework, mine design planning, mine production sequencing and mine transportation scheduling models are integrated and interacted within a whole optimisation system. The proposed integrated framework could be used by mining industry for reducing equipment costs, improving the production efficiency and maximising the net present value.

• Journal of Information Technology Services
• /
• v.7 no.1
• /
• pp.131-149
• /
• 2008

Bandwidth Trading(BT) represents a potential market with over 1 trillion USD across the world and high growth potential. BT is also likely to accelerate globalization of the telecommunications industry and massive restructuring driven by unbundling rush. However, systematic researches on BT remain at an infant stage. This study starts with structure analysis of the Internet industry, and discusses significance of Internet interconnection with respect to BT Issues. We also describe the bandwidth commoditization trends and review technical requirements for effective Internet interconnection with BT capability. Taking a step further, this study explores the possibility of improving efficiency of network providers and increasing user convenience by developing an architectural prototype of Hub-&-Spoke interconnection model required to facilitate BT. The BT market provides an Innovative base to ease rigidity of two-party contract and Increase service efficiency. However, as fair, efficient operation by third party is required, this research finally proposes an exchanging hub named NIBX(New Internet Business eXchange).

• Proceedings of the KIEE Conference
• /
• 1995.07a
• /
• pp.420-423
• /
• 1995

The electric arc welding machine with high-frequency inverter is studied in this paper which could make more saving in energy than conventional ones with inherent low efficiency. The inverter circuit has been already adopted to special welding machines such as MIG and TIG for improving operating performances so much. But this adoption has not be applied to conventional ac arc welding machine until now. The proposed technology for higher efficiency is to apply the high frequency inverter, together with noise-cut transformer. Overall output characteristics are investigated in aspect of cost and circuit performance. The proposed system is conducted practical experiments using PWM controller.

• Journal of Korea Multimedia Society
• /
• v.12 no.12
• /
• pp.1769-1777
• /
• 2009

With the advent of the ubiquitous technology age, the progress of network technology has enabled a robust sensor communication, not just in cities, but also in poor surroundings such as deserts, polar regions, or underwater environments. In this paper, we propose a Multiple Acknowledgement (MA) technique to replace the conventional Automatic Repeat request (ARQ) technique. The MA mechanism is to send an Ack to many receivers simultaneously. The CH (master, coordinator) of the unit cluster broadcasts a Beacon frame where Ack information of the previously transmitted data is included. This technique can reduce the number of transmissions and overhead significantly. The proposed technique is a scheme improving the efficiency of an underwater sensor network where the uplink data transmission is the mainstream. The Performance of the ARQ, Block Ack, Pervasive Block Ack and the proposed method were compared with one another and analyzed. The proposed method showed significant performance improvement as compared with the ARQ, BA, and PBA in its channel efficiency.