• Smart Structures and Systems
• /
• v.18 no.1
• /
• pp.93-115
• /
• 2016

A particle tuned mass damper (PTMD) system is the combination of a traditional tuned mass damper (TMD) and a particle damper (PD). This paper presents the results of an experimental and analytical study of the damping performance of a PTMD attached to the top of a benchmark model under wind load excitation. The length ratio of the test model is 1:200. The vibration reduction laws of the system were explored by changing some system parameters (including the particle material, total auxiliary mass ratio, the mass ratio between container and particles, the suspending length, and wind velocity). An appropriate analytical solution based on the concept of an equivalent single-unit impact damper is presented. Comparison between the experimental and analytical results shows that, with the proper use of the equivalent method, reasonably accurate estimates of the dynamic response of a primary system under wind load excitation can be obtained. The experimental and simulation results show the robustness of the new damper and indicate that the damping performance can be improved by controlling the particle density, increasing the amount of particles, and aggravating the impact of particles etc.

• Nuclear Engineering and Technology
• /
• v.41 no.4
• /
• pp.545-548
• /
• 2009

Korean utility has utilized a Periodic Safety Review (PSR) that assesses the cumulative effects of plant aging, modifications, operating experience, technical developments, and site characteristics since 2000. In particular, the assessment and management of plant aging is one of the major areas in PSR. It includes identification of critical Systems, Structures, and Components (SSCs) for aging, assessment of aging effects, and implementation of aging management programs. Since the PSR system was introduced based on the atomic energy acts and related laws, PSRs of eight sets for 12 Nuclear Power Plants (NPPs) that have been operating more than 10 years have been completed. PSRs of two sets for 4 NPPs are currently being carried out. The utility has confirmed that domestic NPPs have been operated safely through these PSRs and have implemented the follow-up corrective activities to increase the nuclear safety. In this paper, the status of PSR implementation is discussed and improvement programs to conduct PSR follow-up corrective activities efficiently for NPPs are suggested based on experiences with aging assessments.

• The Journal of the Convergence on Culture Technology
• /
• v.6 no.4
• /
• pp.553-558
• /
• 2020

Data has emerged as a key driver of national, corporate and individual competitiveness as a result of the entry into the data economy. The value of personal information is increasing in various fields such as customized services and social problem solving. MyData refers to a new paradigm in which individuals have the authority to manage and control their information and make active decisions on where to use and scope of personal information. MyData, which is emerging as a big topic in the data economy, is a necessary concept in an era when the value of data is important, and related laws and systems should be prepared.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.38 no.5
• /
• pp.455-465
• /
• 2020

As cities continue to expand and additional underground structures are constructed, a policy is being planned to expand addresses, which are national framework data. In this study, the application scope of a proposed 3D (three-dimensional) mixed-use complex space for assigning 3D addresses was defined, based on past research on 3D address systems and by analyzing related laws. Underpass shopping malls, underground walkways (excluding underground shopping malls), and 3D mixed-use transfer centers with a gross floor area of 2,000㎡ or more are connected with each space by underground walkways or public paths. In addition, the detailed space corresponding to the public space of the 3D mixed-use complex space was presented and distinguished from the space to which the detailed address is assigned. The criteria for setting the road section were presented based on the intermediate space, which is a characteristic of 3D mixed-use complex spaces. The proposed criteria were applied to the Express Bus Terminal station (3D mixed-use transfer center) and COEX mall (underpass shopping malls). Thus, the road section was set for an unfamiliar 3D mixed-use complex space. However, by applying the proposed criteria to various 3D mixed-use complex spaces, additional and detailed criteria for different cases should be prepared.

• Journal of Korean Society of Rural Planning
• /
• v.18 no.3
• /
• pp.77-89
• /
• 2012

In 2003, "The National Land Use and Planning Act" (NLUP Act) was enacted unifying two old laws; "The Urban Planning Act" enacted in 1962 and "The National Land Use and Management Act" enacted in 1972. One of main reasons of unifying two acts was to extend urban planning-based development systems to rural areas for preventing uncontrolled urban sprawl in rural areas and enhancing or settlling plan-based land use system in rural areas. This paper is conducted with the following specific objectives: i) to critically review the contents of NLUP Act in terms of rational rural land use planning; ii) to evaluate plan-based land use practices in rural area by NLUP Act; iii) to appraise performance level for prevention against unplanned development activities in rural areas by NLUP Act. To accomplish these objectives, we surveyed actural state of rural land use and development system by the new act in two case study areas. Ansung city in Gyeongi province as an urban sprawl region and Hamyang county in Gyeongnam Province as a remote rural area. Study results ascertained that the new act can not effectively control rural land use and not prevent over-use of agricultural land in the positive and effective ways because of followering three points.

• The Journal of Asian Finance, Economics and Business
• /
• v.9 no.9
• /
• pp.191-203
• /
• 2022

The ecosystem for digital payments in India has expanded quickly during the last decade. A synthesis of technical advancements and progressive governmental laws and regulations has fuelled this expansion. Particularly, the UPI system has assisted India in transitioning from a nation heavily reliant on cash for daily transactions to one with fewer cash transactions. The study attempted to determine how Financial Inclusion (FI) through a socio-techno-ecosystem impacts digital payment systems. FI involves ensuring financial services, products, and an adequate amount of credit without discrimination against the weaker section of society. The study has established that FI impacts the UPI. The finance infrastructure thus helps to develop an ecosystem where financial access and the awareness level help people to transit to new channels of payment. We have used secondary data of 27 banks for sixteen quarters and four years, i.e., for the financial years 2016-17 to 2019-20. It is observed from the current study that the offsite_ATM plays a significant role in the value creation of the UPI. Our study implies that it will help retailers, individuals, and business houses to use UPI platforms for swift payments without hassle. Also helpful for industries that are still not digitally disrupted and industry-specific UPI transactions.

• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10a
• /
• pp.324-327
• /
• 1996

This paper describes the robust controller design methods applied to the problem of an automatic system for tow-vehicle/trailer combinations. This study followed an inverse Linear Quadratic Regulator(LQR) approach which combines pole assignment methods with conventional LOR methods. It overcomes two concerns associated with these separate methods. It overcomes the robustness problems associated with pole placement methods and trial and error required in the application of the LQR problem. Moreover, a Kalman filter is used as the observer, but is modified by using the loop transfer recovery (LTR) technique with modified transmission zero assignment. The proposed inverse LQG,/LTR controllers enhances the forward motion stability and maneuverability of the combination vehicles. At high speeds, where the inherent yaw damping of the vehicle system decreases, the controller operates to maintain an adequate level of yaw damping. At backward moton, both 4WS (2WS tow-vehicle, 2WS trailer) and 6WS (4WS tow-vehicle, 2WS trailer) control laws are proposed by using inverse LQG/LTR method. To evaluate the stability and robustness of the proposed controllers, simulations for both forward and backward motion were conducted using a detailed nonlinear model. The proposed controllers are significantly more robust than the previous controllers and continues to operate effectively in spite of parameter perturbations that would cause previous controllers to enters limit cycles or to loose stability.

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.531-536
• /
• 2003

In this paper, a redesigned guidance and control system for a lunar lander is presented. In past studies, the authors developed a trajectory and attitude control system which achieves the vertical soft landing on the lunar surface. It is confirmed that the system has a good tracking ability to a predefined profile and good robustness against a thruster failure mode where a partial failure of clustered engines was assumed. However, under the previous control laws, the landing point tends to be shifted, in response to the system parameter values, from a target point. Also, an unbalanced moment due to a thruster failure mode was not considered in the simulation. Therefore, in this study, the downrange control is added to the system to enable the vehicle to land at a pre-assigned target point accurately. Furthermore, inhibiting the effect of the unbalanced moment is attempted thorough redesigning the attitude control system. A numerical simulation was performed to confirm the ability of the proposed system with regard to the above problems. Moreover, in the past simulations, a low initial altitude was assumed as an initial condition: in this study, however, the performance of the proposed system is examined over the whole trajectory from an initial altitude of 10 [km] to the lunar surface.

• Journal of Biomedical Engineering Research
• /
• v.38 no.4
• /
• pp.205-210
• /
• 2017

The convergence healthcare industry in Korea has been stalled due to conflicts between stakeholders as well as a supplier-centered industry structure. This situation is caused by the structural contradiction in which the Korean industry has a prolonged conflict structure among stakeholders due to a strong regulation and an institutional inertia from the viewpoint of the sociotechnical system. Therefore, it is necessary to identify new system management plan that enhances social acceptability such as laws, customs and ideas while reducing conflicts between stakeholders. In this study, mainly adapting the stakeholder-oriented autopoiesis and focusing on publicness of healthcare, we propose the rationale and direction for policy making to harmonize various systems within the convergence healthcare industry.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.26 no.7
• /
• pp.1401-1407
• /
• 2002

This paper represents an investigation of the vehicle-to-vehicle distance control system using Hardware-in-the-Loop Simulation(HiLS). Control logic is primarily developed and tested with a specially equipped test vehicle. Establishment of an efficient and low cost development tool is a very important issue, and test vehicle approach is costly and time consuming. HiLS method is useful in the investigation of driver assistance and active safety systems. The HiLS system consists of a stepper motor for throttle control, a hydraulic brake system with an electronic vacuum booster, an electronic controller unit, a data logging computer which are used to save vehicle states and signals of actuator through a CAN and a simulation computer using mathematical vehicle model. Adaptation of a CAN instead of RS-232 Serial Interface for communication is a trend in the automotive industry. Since this environment is the same as a test vehicle, a control logic verified in laboratory can be easily transferred to a test vehicle.