• Journal of the Korean Society of Propulsion Engineers
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• v.14 no.2
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• pp.39-45
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• 2010

In the recent years, it is important to evaluate the durability and the reliability of the vehicle, aircraft, and structure. Especially, in case of the vehicle, the durability and reliability are tested by driving test after making prototype vehicles. However, these methods require many costs and efforts for the experiment are needed to react the defects of product. This problems can be settled by simulator which supplies the realistic environments. In this parer, four-axial road simulator with hydraulic power and driving program to operate are made up. The displacement road profile is realized by accelerometers. For the verification the real-vehicle experiment is executed and road profile obtained from the experiment is verified by four-axial road simulator.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.1201-1216
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• 2017

In this study, we described the development of a methodology to measure tip-pinch strength on the paretic hand rehabilitation device and aimed to investigate reliability of the device. FSR sensors were embedded on the device, and tip pinch strength was estimated with data collected from the sensors using a developed equation while participants were demonstrating tip pinch. Reliability tests included inter-rater, test-retest, and inter-instrument reliability. B&L Engineering pinch gauge was utilized for the comparison. Thirty-seven healthy students participated in the experiment. Both inter-rater and test-retest reliability were excellent as Intraclass Correlation Coefficients (ICCs) were greater than 0.9 (p<0.01). There were no statistically significant differences in tip-pinch strengths. Inter-instrument reliability analysis confirmed good correlation between the two instruments (r = 0.88, p < 0.01). The findings of this study suggest that the two instruments are not interchangeable. However, the tip-pinch mechanism used in the paretic hand rehabilitation device is reliable that can be used to evaluate tip pinch strength in clinical environment and can provides a parameter that monitors changes in the hand functions.

• Journal of KIISE:Software and Applications
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• v.37 no.7
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• pp.536-547
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• 2010

Relative importance and complexity of recent software is getting increased because the software is needed to provide considerable amount of functions and high performance. Therefore, developing reliable software is importantly issued. In order to develop reliable software, it is necessary to manage software reliability at the early phases, but most reliability estimation models are used at system or operational test phases. In order to develop highly reliable software, it is necessary to manage software reliability at the early test phases based on characteristic of the phases that is developers and testers are not separated and developers perform test and debug activities together. Therefore, a new reliability estimation model considering test and debug time together is necessarily needed. In this paper, we propose a new reliability estimation model to manage reliability of individual units from the early test phases and in order to show how to fit the model to actual data and usefulness, we collected industrial data and used it for the experiment.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.382-385
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• 2007

The optimal design and characteristic analysis of Double Fed Induction Generator(DFIG) was performed. The purpose of the paper is to verify the accuracy of design and the reliability of DFIG by experiment. A grid connection experiment is performed to confirm generating performance in wide operating range. In this experiment, 2.7MW M/G set is used. The finite element method is applied to calculate parameters and characteristic analysis of DFIG. And in order to reduce design time and efforts, Design of Experiment(DOE) is used. The experimental results are compared with the optimum design results.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.12
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• pp.1045-1055
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• 2013

It is true that the dependency on import is currently high in case of the safety checkup system of domestic airplanes, and it is at the point of time that localization of HUMS for small airplanes is required. In this study, the design factors were selected for the lightweight of HUMS for small airplanes by using Pro-Engineer which is a design tool and Abaqus. 9 models were made through experiment plans with Taguchi method for this, and the each model for weight lightening was selected through vibration analysis and shock analysis while in operation with experiment profile values. After fabricating HUMS, it was verified that as a result of experiment with the same profile values as the analysis, there was similarity between the analyzed values and values of the experiment. As a result of performing weight lightening which is the purpose of the study, electronic performance for small airplanes is assured and a design plan reducing 15 % weight compared to the targeted weight was deduced. Besides, it could be verified that the light weight model satisfied the maximum allowable displacement value of PCB[printed circuit board] and accordingly satisfied electronic properties of HUMS. In this study, the reliability of a product was certified through the result of an experiment on ground. If the reliability of HUMS were verified through a test flight in the future, it is considered that it would make a big contribution to localization of aerospace electronic equipment.

• Journal of Korean Physical Therapy Science
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• v.29 no.1
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• pp.30-40
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• 2022

Background: This study analyzed the reliability of smart guides for gait analysis in patients with stroke. Design: Cross-sectional study. Methods: The participants of the study were 30 patients with stroke who could walk more than 10 m and had an MMSE-K test score of ≥24. Prior to the experiment, the subjects or their guardians entered their demographic characteristics including gender, age, height, weight into the prepared computer. The experiment was conducted in a quiet, comfortable, and independent location, and the patient was reminded of the equipment description, precautions, and safety rules for walking. A smart insole was inserted into the shoes of the patients and the shoes were put on before the patients walked three times on the 5-m gait analysis system mat installed in the laboratory. Results: The reliability of the equipment was compared with that of the gait analysis system, and the results of this study are as follows: among the gait analysis items, velocity had an ICC=0.982, the cadence had an ICC=0.905, the swing phase on the side of the gait cycle had an ICC=0.893, the swing phase on the side of the gait had an ICC=0.839, that on the non-affected side had an ICC=0.939, single support on the affected side had an ICC=0.812, and support on the non-affected side had an ICC=0.767. Conclusion: The results of this study indicate no statistical difference between the smart insole and the gait analysis system. Therefore, it is believed that real-time gait analysis through smart insole measurement could help patients in rehabilitation.

• Journal of the Microelectronics and Packaging Society
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• v.29 no.3
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• pp.31-35
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• 2022

Recently, with the 4th industrial revolution, the demand for high-density semiconductors for large-capacity data processing is increasing. Researchers are interested in researching the reliability of surface mount technology (SMT). In this study, the effect of PCB pad design on assembly and adhesion reliability of passive component was analyzed using design of experiment (DOE). The DOE method was established using the pad length, width, and distance between pads of the PCB as variables. The assembly defect rate of the passive element after the reflow process was derived according to the misplacement direction of the chip resistor. The shear force between the passive element and the PCB was measured using shear tests. In addition, the shape of the solder according to the pad design was analyzed through cross-sectional analysis.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.12
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• pp.1150-1159
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• 2011

Reliability is defined as a probability that a system will operate properly for a specified period of time under the design operating conditions without failure. Reliability-Redundancy Optimization Problem(RROP) involves selection of components with multiple choices, redundancy levels and redundancy strategy(Active or Standby) for maximizing system reliability with constraints such as cost, weight, etc. Based on the design configuration of Multi-Spectral Camera(MSC) system of KOMPSAT-2, the mathematical programming model for RROP is suggested in this study. Due to the nature of RROP, i.e. NP-hard problem, Parallel Particle Swarm Optimization(PPSO) algorithm is proposed to solve it. The result of the numerical experiment for RROP is presented as instance of recommended design configuration at some mission time.

• KIEAE Journal
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• v.13 no.1
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• pp.109-123
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• 2013

The study is to probe a technical alternative to enhance the reliability and accuracy of the results of various landscape simulations. This study to present technical criteria that are necessary in each stage of target site analysis, picture taking, and computer synthesis and, through these to present supplementary plans to enhance the reliability and accuracy of landscape simulations. In order to derive more practical and empirical results in terms of the reliability of the results of landscape simulations, examples that actually passed landscape review were selected. With regard to study process, an analysis was made first to analyze the landscape report data of designs that passed the review to analyze their characteristics, to be followed by an integrated analysis of problems that were revealed in various landscape simulations. Important factors that affect directly the work of landscape simulations such as the specification of camera lenses that were used in picture taking, distance, and angle. Design the work was carried out using Auto CAD, 3DS Max, and Photoshop program in the same way as in actual design. For verification of their accuracy and reliability, the results were entrusted to experts who have implemented similar jobs. To seduce differences from those too landscape simulations that conduct trial experiment of the virtual space that are to be created in the future with accurate numerical values.

• Communications for Statistical Applications and Methods
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• v.23 no.1
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• pp.57-70
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• 2016

Type-II progressive censoring is one of the censoring methods frequently used in clinical studies, reliability trials, quality control of products and industrial experiments. Sometimes in Type-II progressive censoring experiments, the failure rate is low so the waiting time to observe the $m^{th}$ failure will be very long; however, the experimenter may have to terminate the experiment before a predetermined time. In this article, if two generalized types of Type-II progressive censoring are reminded, we then make some changes in the removal method of Type-II progressive censoring such that without reducing the deduction quality, the termination time of the experiment decreases. This can be done with decreasing withdraws throughout the steps of the experiment with a special reasonable method. A simulation study is done and the results are tabulated at the end of this article for a comparison between introduced method and Type-II progressive censoring.