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This paper presents the important features of structure-dependent model predictive control (MPC)-based approaches for automatic generation control (AGC) considering network topology. Since power systems have various generators under different topologies, it is necessary to reflect the characteristics of generators in power networks and the control system structures in order to improve the dynamic performance of AGC. Specifically, considering control system structures is very important because not only can the topological problems be reduced, but also a computing system for AGC in a bulk-power system can be realized. Based on these considerations, we propose new schemes in the proposed controller for minimizing inadvertent line flows and computational burden, which strengthen the advantages of MPC-based approach for AGC. Analysis and simulation results in the IEEE 39-bus model system show different dynamic behaviors among structure-dependent control schemes and possible improvements in computational burden via the proposed control scheme while system operators in each balancing area consider physical load reference ramp constraints among generators.

Printed electronics have recently attracted extensive attention due to their superior productivity to conventional semiconductor fabrication methods. To develop printing devices optimized for printed electronics, numerical studies on ink flows are often necessary, and, therefore, it is critical to provide accurate ink properties for reliable numerical results. However, it is difficult to find such data in literature since inks for printed electronics contains conductive metallic nanoparticles and they are not only non-Newtonian but expensive. Thus, we propose utilizing a microfluidic chip to investigate rheological properties of conductive inks. By using micro particle image velocimeter along with an immersion oil technique, we examine the flow characteristics of two commercial conductive inks containing Ag nanoparticles on microfluidic chips. We found that the ink flows show a stronger shear-thinning behavior as the Ag content increases. Finally, suitable rheological models applicable to numerical simulations for those inks are suggested after comparing the experimental data to frequently used rheological models.

In these days energy demand is dramatically increasing on the developed and developing countries. Even though the electric power efficiency is gradually improved, the limited energy resources and the shortage of land to construct generations have been existed for long time ago and the environmental limitation like the Kyoto-Protocol is originated. To overcome these obstacles, there is one solution through the cooperation on the national-wide. That is, we should meet the energy problem with having strong relationship among nations. The technological and systemic cooperation on electric power system is much more important than before. It is sure that there are economical and systemic advantages over the limitations when inter-regional power systems are operated well. Simply, power system interconnection gives the eco-friendly energy' applications and the flexible operating power system. In this paper, the first is focused on the algorithms on the power system and the other is based on the economic side. It is mainly to discuss the tertiary control illustrated over each first and secondary controls existing on two control areas.

Over the decades, the ISSC committee “Fatigue and Fracture” has been a major contributor to address the impertinence of good science work within the field. Fatigue and fracture mechanics have been an area with high focus on research the last 50 years with several books, publications and conferences covering these topics. Fatigue failure of structures has caused fatalities. The first known and highly addressed accident, which caused loss of several human lives, was the Versailles Railway accident in 1842. Almost 110 years after this accident, a meeting was held in London, U.K., with the most distinguished fatigue specialists at that time. They concluded that even in 1956 it was not a practical proposition to present a detail overview of the topics of metal fatigue since there was already “at least 4 books in the English language” addressing this topic. It is important to notice that the subject is vast and the committee can therefore not cover all topics related to fatigue and fracture. Hence, the topics in the current report have been selected based on the knowledge and interest of the members of the committee. The report is an overview and sometimes detailed description of recent activities within the offshore and ship industry with focus on the latest research on fatigue and fracture. More than 270 publications have been reviewed and referenced. The committee has been in contact with several of the other committees in order to prevent duplications of work within ISSC.

This paper, based on the Northeast Asia (NEA) power system interconnection, presents an integration of renewable generation (RG), demand response (DR) or distributed generation (DG), high-voltage direct-current (HVDC), and nuclear power plant load-following operation under Smart Grid (SM) in the South Korean power system. The reliable power system depends on considering the reliability that affect after the system is connected or disconnected. The land-to-land power system interconnection in NEA countries will use as the back to back (BTB) technique for power transmission lines; whereas the point-to-point (PTP) will be used for over-sea interconnection, such as a Jeju Island and South Korea-Japan submarine transmission. In this paper, we will suggest how to design and analyze the operation mechanism/algorithm of the reliability side for the NEA, and an integration of RG, DR, HVDC, and nuclear power plant load-following operation under SM in the South Korean power system. Also, we present an inter-area power flow map for a power flow analysis for NEA countries to relieve the possible future power imbalances within the metropolitan areas or the southeastern area of Korea.

Gas explosion accidents have been recognized as a major hazard of offshore facilities in oil & gas industries. Due to the nature of offshore topside structures, even a single collapse of structural members or equipments may lead to enormous economic and environmental losses. Therefore, such potential hazards that cause the accidental collapse need to be evaluated closely. Gas explosion has been categorized as an important issue of the design of offshore structures regarding the severity of the accident. This paper presents practical considerations for the nonlinear dynamic structural analysis of offshore structures under blast loadings from gas explosion accidents. Numerical investigations including modeling of blast loads and idealization of structural materials and members have been conducted for the overall topside structures. As a design step for offshore structures under blast loadings, an applicable guidance on the finite element analysis (FEA) is described in this study.

In this paper, a virtual power system simulator (VPSS) using a virtual power plant (VPP) concept is introduced. VPSS efficiently emulates power system operations and electricity transactions in order to protect the access to future electricity markets utilizing the power system interconnections in Northeast Asia (NEA). This paper introduces methods on how to structure and operate the operative mechanism and the simulator design for these proposed inter-regional interconnections in the NEA. The inter-regional power system interconnection structure is expressed by using an interregional scenario performed by the Integrated Inter-Regional Transmission Organization (IIRTO). In these NEA countries, electric power bidding scenarios and price signal scenarios are options that are able to be defined by one VPSS based on the IIRTO parameters.

These days energy demand is gradually increasing around the world. Even though the electric power efficiency has been continuously improved, limited energy resources and the shortage of land to construct generators are still unsolved problems. Also, there are environmental limitations such as the Kyoto-Protocol. There is a lot of research to deal with those things. National-wide cooperation is progressing on this research. Trades among energy-rich nations and energy-poor nations are a reasonable answer to meet the demands. Power system interconnection gives eco-friendly energy' applications and a flexible operating power system. This paper is focused on a scheme for an interconnected power system based on the economic side. It is mainly to discuss the power system market dynamics algorithm illustrated over a separate market structure.

Many electric power suppliers are suffering from huge losses due to higher cost related to generation of resources, especially fossil fuel. Many ideas have been proposed to renovate the price distortion in the electricity market. Among these ideas, smart metering system has been considered as an effective method for improving the pattern in power consumption of energy consumers thus reducing the financial burden of electricity companies. In this paper, we reviewed smart metering system of other countries and explained our development of smart metering system specialized for Korean residential environments. With this developed system, we have conducted a pilot demonstration for 2 months in the winter season Dec. 2008 to Feb. 2009. 77 various sized households in two different cities volunteered to participate in this demonstration. During this demonstration, our study focused on verifying the effectiveness of IHD (In-Home Display) which is an essential component of Korean smart metering system. The result of this demonstration is also included in this paper.

This paper presents several investigations for improved structural analysis method of wheel loaders based on the static and dynamic measurements including strength and motion characteristics. Physical quantities such as stresses, hydraulic cylinder pressures and strokes were obtained from static tests for prepared operating scenarios. The dynamic measurements were also carried out for two types of motions: simple reciprocations of a boom and a bucket and actual working motion including traveling, digging and dumping. It was shown from static measurements that static stress level induced by the bucket cylinder operation was higher than that by the boom cylinder operation. It was confirmed from dynamic measurements that stress histories during actual working seemed to be static rather than dynamic. A fully assembled finite element model was prepared for structural analysis. A practical trial and error scheme was adopted in order to handle non-linearity caused by lift-up of wheels. For both measurements and structural analysis, it was shown that structural behaviors with the brake on were quite different from those with brake off. Sensitivity analysis showed that there was much difference between digging forces from conventional formula and structural analysis.Copyright © 2004 by ASME

Abstract As potential offshore oil fields shift from shallow water to deeper ocean, floating production, storage and offloading (FPSO) systems become more attractive than conventional huge fixed type platforms. Recently we have successfully completed conversion works of two FPSO's from old 280,000 DWT VLCC's and they will be towed and installed at Campos Basin, offshore Brazil. During this project elaborate hydrodynamic and structural analyses were performed to ensure proper function as an FPSO and to convince safety during conversion and towing stage. This paper summarizes general arrangement and typical results of the analyses. Introduction As potential offshore oil fields shift from shallow water to deeper ocean, floating type production platforms such as floating production. storage and offloading (FPSO) systems become more attractive than conventional huge fixed type platforms. The FPSO system is known as economical alternatives to fixed type platforms for deep water applications. Since FPSO has integrated function of production, storage and offloading, its conceptual design is very important to ensure the full performances or these multifunctions. Especially, mooring system has a unique device called turret. Turret enables the FPSO to weathervane with minimum environmental mooring force. A multi-path fluid swivel acts an essential role for oil transfer without leakage during weathervaning. In order to reduce operational cost mooring scheme without thruster-assistance is preferred in spite of quite deep water of around 1,000 meters. Recently Hyundai Heavy Industries has successfully completed conversion works of two FPSO's for Petrobras. Henrique Dias and Jose Bonifacio, from old 280.000 DWT VLCC's and they will be towed and installed at Campos Basin, offshore Brazil. During this project, elaborate Analyses1 were performed to ensure proper function as an FPSO and to convince safety during conversion and towing stage. It covers naval architectural calculations. stability. motion mooring, and fatigue analysis for in-place condition and/or towing condition. Also various global and local structural analyses were performed for floating construction, towing and in-place conditions. During the structural analysis, special attention was paid to consider highly corroded areas arisen from the previous usage as a VLCC. This paper summarizes general arrangement and typical results of the analyses for the Jose Bonifacio. General Arrangement Basically, the hull is converted from 280.000 DWT VLCC that is 17 years old. The general arrangement and principal particulars of FPSO are shown in Figure 1 and Table J respectively. It is claimed that the locations of a flare boom a turret and accommodations are important factors for general arrangement. Generally, the location of accommodation is arranged at stem part as it was for converted hull case. Therefore, the location of the flare boom is at bow which is far from accommodation to prevent the hazardous condition. in spite of forward direction against wind direction. Turret opening may be either at the midship or bow. To ensure the good weathervaning, bow is preferred in our case. However, midship may be chosen in cooperation with thruster-assisted mooring to improve the heave motion characteristics. On the forward part of main deck, a turret and a flare boom are installed.