• International Journal of Highway Engineering
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• v.17 no.3
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• pp.13-25
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• 2015

PURPOSES : This paper aims at the implementation of a balanced scorecard that can be widely applied to modern business management for use in the public road management sector. METHODS : This study applied the newly developed LOS-based balanced scorecard system instead of a traditional Key Performance Index (KPI) for better decision making in asset management planning. As an evaluation technique, a" hierarchical alignment and cascading method" is also suggested. Finally, the suggested system has been empirically applied to a regional government. RESULTS : To provide stable and sustainable road services, the balanced scorecard informs the regional government of needed improvements in its asset management plans regarding budget optimization, structural management, the development of inner-business processes, and human resources. CONCLUSIONS : An LOS-based balanced scorecard for managing road services and organizations in a quantitative manner has been successfully developed and tested through a field study. The developed scorecard is a timely topic and a useful analytical tool for coping with the new phases of an aging infrastructure, tighter budgets, and demand for greater public accountability.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.157-159
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• 2017

This paper presents a storage reliability evaluation method based on the accelerated degradation test for the engine assembly and parts of the guided missile. The test of the engine assembly is performed at accelerated conditions equivalent to the real storage period, and then the aging condition of parts is checked. For engine parts, performance degradation characteristics are measured periodically at the accelerated conditions and failure times are predicted at each condition. Storage lifetime at normal use conditions is predicted using an accelerated model and failure times at all accelerated conditions.

• KIEAE Journal
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• v.14 no.1
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• pp.121-129
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• 2014

As time passes, the aging of the plant building, the building's energy performance degradation than the initial plan does not express a situation could arise. This year, the certification of buildings certified in 2009 has expired for measures such as the situation required. In this study, management of national and international green building certification and re-certification was compared in two ways. First, the evaluation of green building certification system management assessments were compared. Second, the green building certification system for the re-certification analysis. As a result, G-SEED was not reflected life-cycle of building in management assessment and the commissioning of G-SEED is the UK and the U.S and other concepts of evaluation. In addition, the re-certification system is insufficient about substantial energy consumption of buildings. In this study, the revised the management assessments in conjunction with the re-certification system to manage the building is proposed to improve. In addition, the current evaluation of the existing building certification "existing building" and "building the first certified" as it is more efficient to separate the information into assessment was judged. Green building certification system to meet the purpose of management and operation, and disposal phases of the building to promote energy conservation and sustainability in order to the management a systematic and detailed evaluation and re-certification system developed for the revision of the specific items required and future research want to continue.

• Industrial Engineering and Management Systems
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• v.4 no.1
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• pp.54-67
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• 2005

This paper provides an evaluation of an optimization-based, multiple-input double-output (MIDO) run-to-run (R2R) control scheme for general semiconductor manufacturing processes. The controller in this research, termed adaptive dual response optimizing controller (ADROC), can serve as a process optimizer as well as a recipe regulator between consecutive runs of wafer fabrication. In evaluation, it is assumed that the equipment model could be appropriately described by a pair of second-order polynomial functions in terms of a set of controllable variables. Of practical relevance is to consider a drifting effect in the equipment model since in common semiconductor practice the process tends to drift due to machine aging and tool wearing. We select a typical application of R2R control to chemical mechanical planarization (CMP) in semiconductor manufacturing in this evaluation, and there are five different CMP process scenarios demonstrated, including mean shift, variance increase, and IMA disturbances. For the controller, ADROC, an on-line estimation technique is implemented in a self-tuning (ST) control manner for the adaptation purpose. Subsequently, an ad hoc global optimization algorithm based on the dual response approach, arising from the response surface methodology (RSM) literature, is used to seek the optimum recipe within the acceptability region for the execution of next run. The main components of ADROC are described and its control performance is assessed. It reveals from the evaluation that ADROC can provide excellent control actions for the MIDO R2R situations even though the process exhibits complicated, nonlinear interaction effects between control variables, and the drifting disturbances.

• The Journal of the Convergence on Culture Technology
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• v.6 no.2
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• pp.535-541
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• 2020

A conventional elastic material replacement and performance evaluation are very complicated and time-consuming, and it is difficult to know when to replace the elastic material in advance. By comparing with the product limit and the functional limit, the necessity of elastic material replacement and the improvement of track support stiffness according to replacement can be immediately demonstrated based on experimental data. Using an evaluation system of track support stiffness, the performance evaluation data for elastic materials obtained through field tests using software for track support stiffness is integrated and managed on the administrator's computer. Therefore, the replacement plan is established and maintenance history is managed by identifying the replacement time and location of elastic materials. It is possible to evaluate the performance and condition of the elastic material at the various points during the working time of the track inspection and the track performance (track support stiffness) and durability of the elastic material (aging level, spring stiffness variation rate, etc.) at the operation condition. The elastic material could be replaced timely, and the deterioration of the elastic material can be continuously monitored.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.1
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• pp.90-95
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• 2011

A Kick Motor, KSLV-I second stage propulsion system, utilizes a flexible seal for pitch and yaw axis controls during combustion. A flexible seal consists of the alternate laminate of rubber and composite reinforcement between forward and aft rings. A Kick Motor nozzle is rotated by the shear deformation of rubber layers. Consequently, the development of rubber, which is appropriate to the usage condition of flexible seal, is very important. A tensile test, QLS test (shear modulus and failure shear stress), and aging test have been carried out to confirm the performance of rubber developed. Test results show that the shear modulus of rubber are 0.4310 ~ 0.4997MPa and the failure shear stress is more than 2.5MPa.

• Journal of the Korean Wood Science and Technology
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• v.42 no.1
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• pp.20-26
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• 2014

This paper represented the finite element analysis to estimate structural performance of stress-laminated deck, which is determined by deflection, stress, and aging characteristics of tensioning. After loading, the deflected shape showed plate behavior because pre-stressing make frictional force between each member. Compared between initial post-tension and the results, pre-stressing forces were decreased with deck deflection. This is because deflection occurred in the deck so that pre-stressing decreased due to load reduction. However, material plasticity was not considered so that advanced researches should be performed.

• Structural Monitoring and Maintenance
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• v.3 no.1
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• pp.51-69
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• 2016

Monitoring the performance and estimating the remaining useful life of aging civil infrastructure in the United States has been identified as a major objective in the civil engineering community. Structural health monitoring has emerged as a central tool to fulfill this objective. This paper presents a review of the major structural monitoring programs that have been recently implemented in the United States, focusing on the integrity and performance assessment of large-scale structural systems. Applications where response data from a monitoring program have been used to detect and correct structural deficiencies are highlighted. These applications include (but are not limited to): i) Post-earthquake damage assessment of buildings and bridges; ii) Monitoring of cables vibration in cable-stayed bridges; iii) Evaluation of the effectiveness of technologies for retrofit and seismic protection, such as base isolation systems; and iv) Structural damage assessment of bridges after impact loads resulting from ship collisions. These and many other applications show that a structural health monitoring program is a powerful tool for structural damage and condition assessment, that can be used as part of a comprehensive decision-making process about possible actions that can be undertaken in a large-scale civil infrastructure system after potentially damaging events.

• Journal of the Korean Society for Precision Engineering
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• v.34 no.2
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• pp.115-123
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• 2017

This paper presents the design and the control performance of a novel dynamic compliant-arm support with parallel elastic actuators that was developed to assist with the daily living activities of those whose arms are compromised by muscular disease or the aging process. The parallel elastic-arm support consists of a compliant mechanism with combined passive and active components for human interaction and to reach the user's desired positions. The achievement of these tasks requires impedance control, which can change the virtual stiffness, damping coefficients, and equilibrium points of the system; however, the desired-position tracking by the impedance control is limited when the end-effector weight varies according to the equipping of diverse objects. A prompt algorithm regarding weight calibration and friction compensation is adopted to overcome this problem. A result comparison shows that, by accurately assessing the desired workspace, the proposed algorithm is more effective for the accomplishment of the desired activities.

• Smart Structures and Systems
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• v.23 no.3
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• pp.227-242
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• 2019

Seismic isolation systems employ structural control that protect both buildings and vibration-sensitive contents from destructive effects of earthquakes. Structural control is divided into three main groups: passive, active, and semi-active. Among them, semi-active isolation systems, which can reduce floor displacements and accelerations concurrently, has gained importance in recent years since they don't require large power or pose stability problems like active ones. However, their seismic performance may vary depending on the variations that may be observed in the mechanical properties of semi-active devices and/or seismic isolators. Uncertainties relating to isolators can arise from variations in geometry, boundary conditions, material behavior, or temperature, or aging whereas those relating to semi-active control devices can be due to thermal changes, inefficiencies in calibrations, manufacturing errors, etc. For a more realistic evaluation of the seismic behavior of semi-active isolated buildings, such uncertainties must be taken into account. Here, the probabilistic behavior of semi-active isolated buildings under historical pulse-like near-fault earthquakes is evaluated in terms of their performance in preserving structural integrity and protecting vibration-sensitive contents considering aforementioned uncertainties via Monte-Carlo simulations of 3-story and 9-story semi-active isolated benchmark buildings. The results are presented in the form of fragility curves and probability of failure profiles.