• Advances in aircraft and spacecraft science
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• v.7 no.3
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• pp.271-290
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• 2020

The paper describes the analysis of deployment strategies and trajectories design suitable for executing the inspection of an operative spacecraft in orbit through re-usable CubeSats. Similar missions have been though indeed, and one mission recently flew from the International Space Station. However, it is important to underline that the inspection of an operative spacecraft in orbit features some peculiar characteristics which have not been demonstrated by any mission flown to date. The most critical aspects of the CubeSat inspection mission stem from safety issues and technology availability in the following areas: trajectory design and motion control of the inspector relative to the target, communications architecture, deployment and retrieval of the inspector, and observation needs. The objectives of the present study are 1) the identification of requirements applicable to the deployment of a nanosatellite from the mother-craft, which is also the subject of the inspection, and 2) the identification of solutions for the trajectories to be flown along the mission phases. The mission for the in-situ observation of Space Rider is proposed as reference case, but the conclusions are applicable to other targets such as the ISS, and they might also be useful for missions targeted at debris inspection.

• International Journal of Highway Engineering
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• v.15 no.5
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• pp.157-166
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• 2013

PURPOSES : This study is to analyze expected effect of a accident decrease when motorcycle safety inspection is introduced. METHODS : Based on the literature review of effect of 4-wheel vehicle inspection, probability of occurring accidents among defective motorcycles are calculated by using the number of estimated defective motorcycles and accidents resulting from defects of motorcycles. Then, the number of decreased accidents which is resulting from eliminating defects of motorcycles by safety inspection is estimated by using probability of occurring accidents among defective motorcycles. RESULTS : If the ratio of eliminating defects of motorcycles is 95% after motorcycle safety inspection, the effects of accident decrease of motorcycle safety inspection are analyzed from 2005 to 2008. As a result, 46,292 defective motorcycles are repaired and 1,376 accidents are prevented when the probability of occurring accidents among defective motorcycles is 2.97%. CONCLUSIONS : This study suggests the expected effect of motorcycle safety inspection is that the inspection can prevent 1,376 motorcycle accidents. However, the number of preventing motorcycle accidents are small, compared with the total number of motorcycle accidents because there are limitations to investigate the causes of defective motorcycle accidents. A more precise analysis of the expected effect of motorcycle inspection is possible when a systematic investigation of the causes of the accidents is implemented.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.6
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• pp.643-653
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• 2020

The concrete lining inspection by inspector after traffic control poses various problems such as congestion caused by traffic control and social loss costs resulting from it, and risks of traffic accidents and safety accidents for inspectors et al. To solve the problems, the concrete lining inspection has been carried out using automatic inspection equipment and image analysis that can be objectively and quantitatively investigated in overseas. In this study, to solve the problems of concrete lining inspection by inspector and to review improvement plan for inspection, inspection was carried out using automatic inspection equipment for ◯◯ tunnel that precision safety diagnosis has been conducted in 2019. Analysis was carried out for both inspection results. Automatic inspection equipment investigated defects in concrete lining such as cracks more accurately than precision safety diagnosis.

• Journal of Auto-vehicle Safety Association
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• v.4 no.2
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• pp.17-21
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• 2012

The periodic technical vehicle inspection is to prevent the accident through the finding and fixing the defects of the vehicle. The periodic technical vehicle inspection in Korea was studied for assessing the adequacy of the inspection frequency. The inspection frequencies of many countries including EU, USA and Japan were compared. The average mileages by the vehicle usage and type were represented. The warranty period and recommended replacement period of parts of the domestic auto makers was studied. Currently, the inspection frequency for the periodic technical vehicle inspection in Korea is appropriate. The pass-fail rate and the cost-benefit analysis for the periodic technical inspection in Korea will be needed in the decision making process for the inspection frequency.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.476-479
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• 2010

In recent years, the deterioration of infrastructures is especially considered. In prestress concrete bridges, one of the important mechanisms of deterioration is the corrosion of the post-tensioned tendon due to environmental agents. In this study, the reliability analysis is performed for a prestress concrete box girder bridge under the pitting corrosion attack with considering the inspection and failure cost. The variation of life-time performance depending on inspection methods have to be quantified. The inspection methods with different accuracy of corrosion detection are presented and applied for model of reliability analysis. The computer program for analysis reliability index of the structure as well as updating process is obtained. An existing bridge is applied for illustrating the influence of inspection cost on the behaviors of structure. Subsequently, the benefit of inspection has shown to predict the time to failure of structure.

• Journal of the Korean Society of Safety
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• v.38 no.4
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• pp.47-53
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• 2023

In the inspection of workplace hazards/risk factors by specialized institutions dedicated to safety management, inspection reports vary based on the inspectors, who lack the authority to enforce improvement of workplace hazards/risk factors. Thus, improvement and accident rates remain steady without decreasing. This study performed a regression analysis on the relationship between improvement and accident rates of categorized inspection items by classifying hazards/risk factors from inspection reports submitted by a specialized safety management institution in Chungbuk after inspecting 10 food and beverage manufacturers over the past three years. The hazards/risk factors were classified into five categories: mechanical, electrical, chemical, human, and environmental. The regression analysis revealed that the improvement rate of hazards/risk factors inspected by the specialized safety management institution influenced accident rates. To enhance improvement rates based on these findings, this study prioritized the correction of the five most frequently cited inspection items with the lowest improvement rates in each area. Based on these inspection items, this study suggested a checklist for use in workplace safety inspections of food manufacturers. This proposed checklist is expected to reduce accident rates in food manufacturing facilities. Currently, guidance and inspection of workplaces are mainly focused on accident rates rather than correcting hazards/risks. Thus, accident rates remain unchanged as workplace risks are inadequately improved according to the unique characteristics of each workplace. When conducting workplace guidance and inspection, policy measures and inspection methods are warranted to increase the improvement rate of hazards/risks.

• Textile Coloration and Finishing
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• v.21 no.1
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• pp.53-58
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• 2009

A real-time inspection system has been developed by combining CCD based image processing algorithm and a standard lighting equipment. The system was tested for defective fabrics showing nozzle contact scratch marks, which were one of the frequently occurring defects. Multi-resolution analysis(MRA) algorithm were used and evaluated according to both their processing time and detection rate. Standard value for defective inspection was the mean of the non-defect image feature. Similarity was decided via comparing standard value with sample image feature value. Totally, we achieved defective inspection accuracy above 95%.

• International Journal of Reliability and Applications
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• v.5 no.1
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• pp.25-36
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• 2004

Ultrasonic inspection system consist of the examination procedures, equipment, and operators. The reliability of nondestructive testing is influenced by the inspection environment, materials and types of defect. It is very difficult to estimate the reliability of NDT due to the various factors. Piping inspection round robin was conducted to quantify the capability of ultrasonic inspection during in-service. In this study, the models for predicting the ultrasonic NDE reliability by logistic model and linear regression model are discussed. The utility of the NDT reliability assessment is verified by the analysis of the data from round robin test with these models.

• Management Science and Financial Engineering
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• v.16 no.1
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• pp.119-135
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• 2010

In this paper, we readdress the optimization problem for minimizing the inspection cost in a back-light unit inspection system, which forms a network including a K-stage inspection system, a source inspection shop, and a re-inspection shop. In order to formulate our objective function when the system is in a steady state, assuming that the number of nonconforming items in a lot follows a binomial distribution when a lot is formed for inspection, we make a steady-state network flow analysis between shops, and derive the steady-state amount of flows between nodes and the steady-state fraction defectives by solving a nonlinear balance equation. Finally we provide some fundamental properties and an enumeration method for determining an optimal value of K which minimizes our objective function. In addition, we compare our results numerically with previous ones.

• International Journal of Quality Innovation
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• v.7 no.2
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• pp.97-124
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• 2006

The purpose of this research is to create an expert risk-based piping system inspection model. The proposed system includes a risk-based piping inspection system and a piping inspection guideline system. The research procedure consists of three parts: the risk-based inspection model, the risk-based piping inspection model, and the piping inspection guideline system model. In this research procedure, a field plant visit is conducted to collect the related domestic information (Taiwan) and foreign standards and regulations for creating a strategic risk-based piping inspection and analysis system in accordance with the piping damage characteristics in the petrochemical industry. In accordance with various piping damage models and damage positions, petrochemical plants provide the optimal piping inspection planning tool for efficient piping risk prediction for enhancing plant operation safety.