• Steel and Composite Structures
• /
• v.43 no.3
• /
• pp.363-373
• /
• 2022

As a key reinforcement connection between a tower and a substructure in offshore wind turbine system, the transition piece is inevitably subjected to cyclic dynamic environmental loads such as wind, current and wave. Therefore, well designed transition piece with high strength and good fatigue resistance is of great significance to the structural safety and reliability of offshore wind power systems. In this study, the structural behavior of the transition piece was studied by an extensive sets of finite element analyses. Three widely used types of transition piece were considered. The characteristics of stress development, fatigue life and weight depending on the type of the transition piece were investigated in the ultimate limit state (ULS) and the fatigue limit state (FLS) of a 5-MW offshore wind turbine to be placed in Korea. An optimal form of the transition piece was proposed based on this parametric study.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.17 no.2
• /
• pp.663-677
• /
• 2023

As the paradigm of future vehicles changes, the interest in automotive semiconductor, which plays a key role in realizing this, is increasing. Automotive semiconductors are the technology with very high entry barriers that require a lot of effort and time because it must secure technology readiness level and also consider safety and reliability. In this technology field, it is very important to develop new businesses and create opportunities through technology trend analysis. However, systematic analysis and application of automotive semiconductor technology trends are currently lacking. In this paper, U.S. registered patent documents related to automotive semiconductor were collected and investigated based on the patent's IPC. The main technology of automotive semiconductor was analyzed through topic modeling, and the technology path such as emerging technology was investigated through cosine similarity. We identified that those emerging technologies such as driving control for vehicle and AI service appeared. We observed that as time passed, both convergence and independence of automotive semiconductor technology proceeded simultaneously.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2022.10a
• /
• pp.351-353
• /
• 2022

There have been several nuclear accidents at home and abroad so far, and there have been major and small damages. Overseas, in order to reduce such accidents, the safety and reliability of nuclear power plant operations have been improved by introducing a technology called Configuration Management. Through basic information on Configuration Management and successful cases of introducing Configuration Management from overseas nuclear power plants, this paper checks the technical parts applicable to Korea and examines whether they can be newly applied by supplementing them for domestic nuclear power plants.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2004.05a
• /
• pp.85-89
• /
• 2004

The paper presents a summary of the multidisciplinary/optimization method for the preliminary design of container feeder vessel. The current scenario in the ship building industry highly focuses on container ship design and construction proving the inherent demand in maritime industry. The design accomplishes the outer circle of the design spiral giving stress in areas of Hull Form Design, Resistance & Propulsion. Empirical relations, model test results, data from built ships, class rules and latest market demands stood as the criteria for the design. Optimization of the design as per the owners requirement. class rules, and the trade route selected are the major challenges met with. Strength. reliability, structural safety and stability have been incorporated in compromising standards.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2007.11a
• /
• pp.209-212
• /
• 2007

It is increased electrical energy consumption with the development of intelligence society in buildings and thus an energy conservation through efficient use of electricity and reliability, safety, etc became more important. This research paper intensively investigated performance based construction specifications and design criteria of electrical installations in domestic and foreign country. It is necessary to analyze the key features based on performance and general trend about contractor guarantee, warranty method, performance design criteria from the investigated data. This paper shows a reasonable performance based construction specifications and design criteria of electrical installations.

• The Journal of Fisheries Business Administration
• /
• v.38 no.1 s.73
• /
• pp.115-132
• /
• 2007

Implementing the automatic identification in supply chain management is essential for effective and efficient process control. Though the GTIN based bar code system is generally used as an automatic identification method in most industries, it can not identify individual item, and is not appropriated for products' reliability and safety management. So the RFID system with EPC is considered as a better solution for resolving those problems. This study reviewed automatic identification code systems and the attributes and characteristics of RFID Gen 2 which became a global standard recently for supply chain management. Particularly, this study analyzed RFID Gen 2 systems' read rates on various conditions including distances between tags and readers and between antennas, condensation, and several packing materials in practical supply chain environment. The results of this study showed that the RFID Gen 2 had high read ratio in practical application and would be adopted as a new automatic identification means for traceability systems.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2006.04a
• /
• pp.507-512
• /
• 2006

There are many risks in constructing tunnel-structure. To prevent these risks from occurring and secure safety, the precise and rapid survey of inside displacement of the tunnel is required. But nowadays the measurement of the crown settlement, convergency, and surface settlement depends on general kinds of method which use total station or level. In the way to provide data about maintaining structure according to recent improvement and progress of measuring technology, 3D laser scanning is used. It solves the problem of reliability in measuring displacement of existing structure, provides material that enables to estimate shape change of structure visually, and makes it possible to deliberate speedy countermeasure. By this three dimensioning it is possible to make efficient use of structure maintenance and field measurement

• 한국신재생에너지학회:학술대회논문집
• /
• 2005.06a
• /
• pp.9-12
• /
• 2005

In this paper. we offer a new monitoring system that controls all of the windfar. it can also apply use general wind turbine systems and real meteorological tower. We propose a hierarchical releiable monitoring system connected by wireless communication channels between monitoring host computer and modular slave measuring subsystems. Our system has two hierarchical subsystems: slave measuring systems, and supervisory host computer. We design and implement that the slave measuring subsystems is placed in meteorological tower and wind turbines, and the supervisory host computer in safety zone, The micro-controller in slave measuring system is duplicated using cold-standby method for reliability. The host computer and slave system constructs a feedback system, with wireless communication channel between them. For monitoring and command function, the supervisory computer is implemented with a Personal Computer using graphic user interface. Consequently. we can get a reliable but economic system.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.58 no.1
• /
• pp.90-94
• /
• 2009

The inundation of substation and ground power equipment breaks out every summer season in low-lying downtown and low-lying shore by localized heavy rain, typhoon and tidal wave. For diminishing flood damage of electrical equipment in the root, flood protection system which is used the basic frame of Pad transformer is developed using pneumatic pressure. This system is established on pressure generator equipment and sensor of flooded level operates at flooding occurrence and is maintained a shutting tightly structure. The system is able to protect indraft water in Pad Transformer and supply the electricity at emergency(flooding). And we tested safety for insulation resistance at flooding and applying an electrical current. We estimate that loss cost which is caused by with flooding and the power failure will be diminished if it is addition to advances the reliability evaluation by setting an example.

• Journal of Korean Society on Water Environment
• /
• v.21 no.5
• /
• pp.431-441
• /
• 2005

The study was carried out to improve and regulate the drinking water quality standard and drinking water quality monitoring substances. For the reliability and safety of finished water, It has been monitored for trace organic and inorganic compounds of 333 in finished water of water treatment plants during 1989 to 2003. As a result of monitoring, 51 compounds were detected from 333 compounds, and it has been regulated the drinking water quality standard of 26 substances and 20 mitoring substance. Improvement and regulation method of the drinking water quality standard was performed by comparing and analyzing with detection concentration, detection frequency, risk assessment and foreign drinking water quality standard.