• Proceedings of the Korea Society for Energy Engineering kosee Conference
• /
• 2007.11a
• /
• pp.265-268
• /
• 2007

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 1994.10a
• /
• pp.152-159
• /
• 1994

One of the main objectives of the study is to propose a pratical and realistic reliability analysis by ETCM(Expected Total Cost Minimization). This study is intended to propose the safety assesment and capacity rating of existing reinforced concrete members by evaluating the safety evaluation index, that is RF(Rating Factor) from the results of the field test and inspection for 5 reinforced concrete bridges. ETCM method is used for the reliability analysis of the proposed models. The proposed reliability model and method are applied the safety assesment and system factors of reinforced concrete members.

• Proceedings of the Korean Reliability Society Conference
• /
• 2000.11a
• /
• pp.87-95
• /
• 2000

The testing product is the HSU(Hydrostatic Steering Unit) installed in the armored vehicle which has the compact structure of assembly with hydraulic pump, hydraulic motor, and several hydraulic valves. There are no assesment testing code for HSU within a country because the testing code for HUS is not involved in the technical concert from USA. Therefore the testing code is developed by the dynamic analysis of the armored vehicle. By the developed testing code, the test equipment is designed, manufactured, and used to apply the assesment test.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2005.05a
• /
• pp.147-150
• /
• 2005

This paper presents a method for the load capacity assesment of reinforcement concrete deep beams using nonlinear finite element analysis. A computer program, named RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), for the analysis of reinforced concrete structures was used. From the results, determine the reliability index for the failure base from the Euro Code. Then, calculated additional reduction coefficient to satisfy the goals from the reliability analysis. The proposed numerical method for the load capacity assesment of reinforced concrete deep beams is verified by comparison with the others methods

• Journal of Applied Reliability
• /
• v.14 no.4
• /
• pp.230-235
• /
• 2014

The failure modes of pneumatic directional control valves include leakage, wear of the spool seal, and sticking of the spool. Among them, the main failure mode of the valve is leakage. The leakage is caused by the wear of the spool seal. However, due to the characteristics of the seal material, the leakage rate is fluctuated a lot rather than constantly increased over time. If life analysis is performed using the first time data of leakage failure, predicted life cycles can be different from the real life cycles. This paper predicts life cycles of the pilot pneumatic directional control valve based on the three point moving average which considers the average of the fluctuating leakage rate.

• New & Renewable Energy
• /
• v.16 no.4
• /
• pp.49-64
• /
• 2020

Photovoltaic and Thermal collector (PV/T) systems are renewable energy devices that can produce electricity and heat energy simultaneously using solar panels and heat exchangers. Since PV/T systems are exposed to the outdoors, their reliability is affected by various environmental factors. This paper presents a reliability test for a PV/T system and evaluates the test results. The reliability assessment entails performance, environment, safety, and life tests. The factor that had the greatest influence on the life of the system was the hydraulic pressure applied to the heat exchanger. A test was conducted by repeatedly applying pressure to the PV/T system, and a reliability analysis was conducted based on the test results. As a result, the shape parameter (β) value of 5.6658 and the B10life 308,577 cycles at the lower 95% confidence interval were obtained.

• The Journal of Korean Association of Computer Education
• /
• v.19 no.4
• /
• pp.11-20
• /
• 2016

In this paper, I developed a assesment indicator to evaluate SW program developed by students in SW education. The SW education carry out in elementary school, middle school and high school from 2016. But the assesment indicator to evaluate SW program had not been developed until now. Therefore, I tried to develop the assesment indicator that have harmoniously educational characteristic and SW qualitative characteristic. First of all, I had set the 15 attributes for assesment and developed the 36 criteria for 15 attributes. And the validity of 15 attributes and 36 criteria for assesment had been reviewed by 39 SW educational experts. As a result, the 15 attributes and 36 criteria for assesment were determined to which that have validity. I expect that the assesment indicator developed in this paper will raise the reliability of evaluation in SW education. And the assesment indicator may be used at SW competition conference for teenagers.

• Journal of the Korea Concrete Institute
• /
• v.17 no.6 s.90
• /
• pp.955-962
• /
• 2005

Still no accurate theory exists for predicting ultimate shear strength of deep reinforced concrete beams because of the structural and material non-linearity after cracking. Currently, the load capacity assesment is performed for the upper structure of the bridges and containing non-reliability in the applications and results. The purpose in this study is to evaluate analytically the complex shear behaviors and normal strength for the reinforced concrete deep beams and to offer the accuracy load capacity assesment method based on the reliability theories. This paper presents a method for the load capacity assesment of reinforcement concrete deep beams using nonlinear finite element analysis. A computer program named RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), for the analysis of reinforced concrete structures was used. Material non-linearity is taken Into account by comprising tensile, compressive and shear models of cracked concrete and a model of reinforcing steel. From the results, determine the reliability index for the failure base on the Euro Code. Then, calculate additional reduction coefficient to satisfy the goals from the reliability analysis. The proposed numerical method for the load capacity assesment of reinforced concrete deep beams is verified by comparison with the others methods.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2002.05b
• /
• pp.691-696
• /
• 2002

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.379-379
• /
• 2000

The robot systems used in nuclear power plants need to be both reliable and safe. As a part of the "Validation of nuclear safety-grade equipment" project, we established reliability analysis program and performed a number of analysis using conventional reliability analysis techniques. This paper describes the procedures, techniques, and results of the analysis utilized in our project. In addition, the paper includes current status of reliability analysis techniques and the summary of foreign case studiesse studies