• Corrosion Science and Technology
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• v.11 no.2
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• pp.43-47
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• 2012

Recently, regulatory bodies quite often encourage to adopt risk-based inspection (RBI) and management programs because they can enhance safety simultaneously with deregulation in Korea. RBI is an integrated methodology that factors risk into inspection and maintenance decision making. This paper describes an example of how to use known risk assessment codes (API 580, API 581 BRD) to address such safety analysis requirements for risk management in the refining industry. Specifically, this paper reports the methodology and the results of implementation to the Crude Distillation Unit(CDU) plant of refinery units using the $KGS-RBI^{TM}$ program, developed by the Korea Gas Safety Corporation in reference of API Codes and ASME PC (Post Construction) with a suitable consideration of Korean situation. The results of the risk and reliability assessment using $KGS-RBI^{TM}$ program are useful in determining whether the detected defects are tolerable or required to be repaired. The subsequent decisions are to manage the future inspection, repair and maintenance planning in the risk reduction control.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.469-472
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• 2008

In general, structures in service gradually lose original performance according to time due to initial defects in design and construction, or exposure to unfavorable external conditions such as repeated loading or deteriorating environment, and in extreme cases, may collapse in large disaster. Therefore, in order to maintain the serviceability of structures at optimal level, advanced structure measuring system which can inform optimal time point and method of maintenance is required in addition to accurate prediction of residual life the structure by periodic inspection. To guarantee the safety level of bridge structure and to prevent from disaster, the integration of safety network for bridge structures are needed. Therefore in this study, to enhance the effectiveness of safety network for bridge, the connection methodologies between safety network and pre-installed bridge monitoring system are investigated.

• KIEAE Journal
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• v.7 no.6
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• pp.127-132
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• 2007

Recently, the cases of lawsuit are growing on residential defects. Though, mostly residential construction companies are trying to mitigate resident's dissatisfaction due to keep the company's brand image by operating customer service team, some representatives of apartment buildings initiate litigations without any negotiation with countrepartner companys incited by planned suit lawyers. But lawsuit takes longtime to sentence(about more than one year), and judged amount of money are very few (averaging about 14%) compared with asserted amount of it. To suggest the improving alternatives, the types and problems of defect lawsuit on apartment complex are analyzed.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.3
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• pp.95-102
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• 2018

In order to understand interaction between building users' occupant performance and building maintenance performance of maintenance management personnel, actual data from maintenance activities of buildings were analyzed. Also, using building defect customer complaint data reported by building user, satisfaction data on building maintenance services of building users and service response time of maintenance management personnel, a method for evaluating interaction of buildings with the same purpose and same size was proposed. Throughout analysis, average number of occurrences per unit area per year for the mechanical complaints in complex building were presented. In addition, using building users' satisfaction with facility management services, attitude of responding to business obstacles, number of occurrences per unit area per year of mechanical complaints and complaint processing speed, interaction was comprehensively identified and compared.

• Journal of architectural history
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• v.29 no.6
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• pp.7-18
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• 2020

The domestic of modern architectural remodeling method emphasizes simple aesthetic elements, and the correct design and construction methods are not established based on quantitative grounds, thus damaging the value of cultural properties. This study attempts to re-examine the value of modern buildings recognized as old buildings. It is a basic step to present the correct remodeling of the building. The design criteria for exterior wall remodeling of modern buildings were presented. These research results are suitable for energy conservation design standards and can prevent defects in buildings. In the future, more accurate analysis will be required by securing physical property values for various domestic materials through subsequent research.

• Journal of Drive and Control
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• v.20 no.4
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• pp.54-63
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• 2023

High and intermittent loading cycles induce fatigue damage to transmission components, resulting in premature gearbox failure. To identify gearbox defects, numerous vibration-based diagnostics techniques, using several artificial intelligence (AI) algorithms, have recently been presented. In this paper, an optimized deep belief network (DBN) model for gearbox problem diagnosis was designed based on time-frequency visual pattern identification. To optimize the hyperparameters of the model, a particle swarm optimization (PSO) approach was integrated into the DBN. The proposed model was tested on two gearbox datasets: a wind turbine gearbox and an experimental gearbox. The optimized DBN model demonstrated strong and robust performance in classification accuracy. In addition, the accuracy of the generated datasets was compared using traditional ML and DL algorithms. Furthermore, the proposed model was evaluated on different partitions of the dataset. The results showed that, even with a small amount of sample data, the optimized DBN model achieved high accuracy in diagnosis.

• The Journal of Engineering Geology
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• v.21 no.3
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• pp.239-246
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• 2011

Upon encountering weathering soil at a construction site, it may be necessary to change the design and construction plans for geotechnical structures. When weathering soil is exposed to air, the weathering process proceeds rapidly, resulting in significant damage to geotechnical structures, particle defects, and an increase in moisture sensitivity. The management of weathering-soil compaction is challenging. Because the engineering properties of weathering-soils vary regionally, it is important to report the result of research into the regional characteristics of such soils. At two locations of granite gneiss in the Gansung area of Gangwon-do, geological studies were performed at 22 and 8 sites, respectively. At each site, test samples were collected for analysis by XRD and to measure particle size, consistency, and compaction. To evaluate the suitability of the material for road subgrade, we examined the interrelationship between CBR value and the uniformity coefficient, the 200 sieve passing ratio and the aggregate ${\geq}$ 2 mm) content. We found that for the weathered granite soil, aggregate sized > 2 mm has a significant effect on the CBR value. In addition, the mixing of aggregate sized > 2 mm with sub-quality soil improves the soil condition.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.4
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• pp.291-296
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• 2014

For the purpose of energy consumption and green-house gas reduction from building, new insulation materials with improved thermal property have been developed and used. Among new insulation materials, mineral hydrate which compensates for the defects of existing materials is using as a prominent insulation material. The fabrication method of mineral hydrate is similar to that of ALC for building structure but mineral hydrate is only used for insulation. The raw materials that make up of mineral hydrate are cement, lime and anhydrite. Especially anhydrite is all dependant on imports. In this study, Desulfurization Gypsum(DG), by-product of oil plant, was used for replacing for imported anhydrite and waste recycling. DG substituted all of anhydrite and a part of lime. Mineral hydrate used DG had analogous thermal and physical properties, compared to existing mineral hydrate.

• Journal of the Korea Institute of Building Construction
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• v.11 no.3
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• pp.208-220
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• 2011

Recently, the arbitration system for defect disputes has been introduced to settle the disputes arising from defects in apartment buildings. However, the conciliation system did not reflect the current technical issues of defect disputes and the opinions of each party involved in the disputes. Moreover, it revealed more imperfections in the content and the process of the system itself. Therefore, this study aims to review the technical aspects of defect disputes, and suggest an alternative to the conventional conciliation system. This paper also discusses logical factors that can be addressed for the current subjective judgment. It is recommended that each party involved in the defect dispute build mutual trust in order to meet social needs, which is the underlying support for the revitalization of the institutional level.

• Journal of Korean Society of Steel Construction
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• v.25 no.5
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• pp.451-461
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• 2013

In steel bridges, there are several details that constrain the deformation such as buckling by external forces. Most of these details which are composed of the intersection members have scallops in order to exclude the weld defects inherently and to get the ease of fabrication and also to decrease the stress concentration. In this study, stress relief hole (SRH) near stress concentration zone with detail category D or under is proposed as a method to improve the resistance on the fatigue crack initiation to detail category C. And the effects of the appropriate size and location of SRH were examined and the applicability to improve the fatigue resistance of the floorbeam web and the rib wall at rib/floorbeam intersection in the orthotropic steel deck bridge was evaluated.