• Journal of Advanced Marine Engineering and Technology
• /
• v.36 no.1
• /
• pp.172-178
• /
• 2012

Packaged power systems are very convenient for transferring and installing, and can supply electric power steadily for the areas which have a great difficulty in drawing power line from the outside. Then, the equipments have been widely used in such mountain areas and the back of beyond. Generally, compressed air has been employed to start the dynamo-engines for P.P.S. However, these systems necessitate air compressors, air tanks, air starting motors and pipe lines for transferring compressed air etc. Recently, starting systems which have only batteries and series DC motors as whole automobiles have been applied due to their simplicity and economy. In this paper, developed new starting motor for the P.P.S. And we achieved the better results from performance tests.: Output power, torque and speed.

• Journal of Digital Convergence
• /
• v.15 no.8
• /
• pp.203-212
• /
• 2017

The National Housing Bond Information Relay System is a representative financial information relay system in which institutions are connected with center system. A centralized structure is expensive to construct and operate center, and there is a problem that all networks are disconnected when a failure occurs in the center system. In this paper, we propose the national housing bond information relay system model based on Blockchain technology that can process information safely and efficiently. The proposed model constructs a Blockchain network so that each institution that processes the national housing bond information can transmit information safely, and each institution manages the same distributed ledge by a smart contract. The proposed model can reduce the cost because it can process complicated national housing bond transaction information without a relay center, and a network usage and disk usage decreased by 1.7% and 8.53%.

• Journal of Convergence for Information Technology
• /
• v.11 no.7
• /
• pp.7-13
• /
• 2021

Recently, due to the many features and advantages of cloud computing, cloud service is being introduced to countless industries around the world at an unbelievably rapid pace. With the rapid increase in the introduction of multi-cloud based services, security vulnerabilities are increasing, and the risk of data leakage from cloud computing services are also expected to increase. Therefore, this study will propose an AWS Well-Architected based security architecture configuration method such as AWS standard security architecture, AWS shared security architecture model that can be applied for personal information security including cost effective of cloud services for better security in AWS cloud service. The AWS security architecture proposed in this study are expected to help many businesses and institutions that are hoping to establish a safe and reliable AWS cloud system.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.30 no.5D
• /
• pp.513-522
• /
• 2010

Underground construction for traffic networks, complexes, and storage facilities has risen as an effective land use plan for dealing with emerging problems such as overcrowded urban cities and traffic jams. This paper performed an economic feasibility analysis of the development of the integrated field management system which provides field workers and managers with 3D-based location tracking and clear communication during underground construction works. To conduct the analysis, processes and problems of field management for underground construction were analyzed and deduction in accidents and field management costs and productivity improvement were estimated as expected benefits. Based on computed benefits and costs, an economic analysis was conducted using Benefit/Cost ratio(B/C), Net Present Value(NPV), and Internal Rate of Return(IRR) and then sensitivity analysis was performed to cope with the uncertainty of assumed variables.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.18 no.6
• /
• pp.211-221
• /
• 2019

The death toll for every 10,000 cars registered in Korea is 1.4, which is still the lowest among OECD members, and the need for rescue and response systems is emerging. In response, the company is developing a vehicle ICT-based emergency rescue system (e-Call) that can handle accidents such as rapid and accurate life saving by automatically sending accident detection and related information to the central center in the event of a traffic accident. However, ordinary citizens are negative about the installation and cost of e-Call services. To solve these problems, various introduction and operation methods of e-Call were proposed for activation of terminal distribution. In addition, the effect of introducing e-Call was analyzed by predicting the penetration rate of e-Call terminals. Analysis shows that 463 to 926 deaths and 3,335 to 6,66.9 billion won will be saved in 10 years after the introduction of e-Call terminals.

• Journal of the Korean Institute of Gas
• /
• v.20 no.5
• /
• pp.57-63
• /
• 2016

Though a valve is a very important part in a system to control properly, it has potential failure caused by gap from valve stem to ball connection, and abrasion, crack, fixation causing operational trouble and accidents. 64% of the valve failure in the real case was the failure of airtightness and most accidents of leakage and explosion were occurred while fixing the failure. While there are no proper safety manual, maintenance procedure and regulation for industrial valves excluding safety valve, safety management for the valves is left to the discretion of the maintenance company. Strict maintenance that removes hazards and emergency response procedure are required to prevent and reduce the loss of accident. This study suggests safety enhancement measures through valve monitoring by investigating the status of use of valve and current maintenance. Enhancement of gas safety management can be acquired by a monitoring system that provides diagnosis for valve status, monitoring real-time gas leakage, management of entire cycle lifetime that can reduce maintenance cost.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.11 no.1
• /
• pp.100-106
• /
• 2018

Since the concept of virtual currency called Bitcoin was announced in 2008, the blockchain technology, which is the basis of Bitcoin, is attracting attention as an important platform technology in the era of the 4th industrial revolution that can change our society in the future. Although Existing electronic financial transactions store and manage all transaction history at a reliable central organization such as government and bank, blockchain-based electronic financial transactions are composed of a distributed structure in which all participants participating in the transaction store and manage the transaction history, it is possible to secure transaction transparency while reducing system construction and operation costs. Besides the virtual currency that started with bit coins, the technology of these blockchains has been extended in various fields such as smart contracts and document management. The key technology area of this blockchain is security based on proven cryptographic technology to make it difficult to forge and hack, but there are security risks such as security vulnerabilities in the virtual currency trading service, We will discuss security risks in using virtual currency and discuss countermeasures. Especially security accidents of virtual currency exchanges are occurring frequently recently, the damage of users who trade the virtual currency is also increasing, we propose security threats and security countermeasures against virtual currency exchanges.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.33 no.1
• /
• pp.305-316
• /
• 2013

To find out if modern roundabout is still effective under drivers behavior and driving conditions in Busan Metropolitan City, the effects before and after introduction of roundabout were analyzed. According to analysis on velocity profile at roundabout, velocity deviation decreased, and average vehicle speed was close to design speed. As a result, it has been confirmed that most roundabouts were properly built. In terms of traffic operation, average vehicle speed improved by 87.2% when a traffic intersection was replaced by a roundabout. therefore, it has been found out that the introduction of roundabout has a positive effect on increasing vehicle speed by reducing traffic congestion. In addition, annual benefits expected from the replacement from a traffic intersection to a roundabout were KRW 872 million as follows; KRW 410 million in traffic communication, KRW 39 million in transportation safety, KRW 255 million in energy saving, KRW 95 million in reduction of air pollution and KRW 73 million in reduction of traffic signal installation cost. In other words, if 10% (193 spots) of all traffic intersections (1,926 spots in total) in Busan City are replaced by roundabouts, the municipal authority would be able to save about KRW 168.3 billion. According to analysis on the benefits expected from the installation of roundabouts compared to the investment cost for traffic intersections, about KRW 679 million could be saved per roundabout. Considering 10% of all traffic intersections in the City of Busan, about KRW 131 billion could be saved annually. The traffic accidents in roundabout usually occur because drivers aren't aware of right-of-way rules. Once the right-of-way rules settle, the number of traffic accidents would significantly decrease. In addition, it is urgent to promote education and campaign for drivers, pedestrians and bikers on the roundabout.

• Journal of Korea Port Economic Association
• /
• v.36 no.3
• /
• pp.99-114
• /
• 2020

Overseas advanced ports are promoting smartification, as well as full automation of the terminals surrounding container terminals. A smart port can be defined as a comprehensive concept that pursues increased operational efficiencies, maximization of profit, efficient use of energy, and construction of eco-friendly ports with the introduction of fourth-industrial-revolution technology, including port automation. However, Korea is making efforts to introduce fourth-industrial-revolution technology into ports, but indications are that they are somewhat insufficient compared to advanced ports abroad. Therefore, this study conducted a survey about operators and users of container terminals in Gwangyang Port by deriving the factors determining the introduction of smart ports, such as cost, service, time, safety, and environment, from previous studies. This study analyzed the factors determining the introduction of smart ports and moderating effects when the adjustment variables of operators and users were applied to the pros and cons. As a result of the analysis, it was found that port operators and users have a moderating effect on cost, time, safety, and environmental factors, but not on service factors. These results indicate that port operators try to reduce costs through efficient operation, time management, and by reducing safety accidents by building smart ports, but analysis showed that the negative effects of smart ports have affected port users. The results of this study were derived through a moderated regression analysis and suggested implications for introducing smart ports in the conclusion.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2012.05a
• /
• pp.378-379
• /
• 2012

Nowadays, great energy consumption in advanced electrical industry has called up the great y efficiency. Electric power IT industry such as intelligent electric power system is receiving great attention and being marked up as a new growth engine. Through Intelligent electric power system, the electric power supply can be balance optimized according to demand, giving huge cost savings advantage for energy imports, infrastructure construction and operation. Nevertheless, the intelligent system promotes better reliability in power supply. Manual electric power management using man power appears to be non-practical. Real time electric power management on all facilities and equipment can be done through an intelligent electric power system, any accident break out issue can be easily recorded and recognized. In this paper, a fully integrated intelligent switchgear electric management system is developed to monitor and remote control the electrical switch based on smart phone. The proposed system is superior than the existing switchgear management system's weakness and can sharply improve effectiveness and stability with low cost. In future, the proposed system is expected to be greatly contributed to the advancement of the IT industry in electric power management.