• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.379-388
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• 2016

There are various system defects from weapons manufacturing due to the numerous production processes and various production environments. The first kind of defect is patent defects, which can be detected by visual inspection, functional testing, and existing quality control procedures during the manufacturing process. The second kind is latent defects, which cannot be detected though existing quality management approaches because of the complexity of the system and manufacturing process. To minimize the initial defect problems, environmental stress screening (ESS) is needed to detect the defects, remove them, and improve the product conditions based on the environmental stress conditions of temperature and vibration. We implemented a tool for quantitative ESS effectiveness analysis and profile design automation based on MIL-HDBK-344 and verified it using six scenarios with different temperature stress, vibration stress, and test designs.

• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.871-873
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• 1999

According to the reports about the failure mode analysis of modules and systems, It is said that there are many early failure of system. To remove latent defects which causes early failures like that, It is necessary that screening test is performed. ESS is often used fur screening electronic equipments, and is proposed by the most powerful tool for removing latent defects of electronic equipments. [1][2] In this report, the procedure of the environmental stress screening which uses the temperature cycling stress is proposed. It is considered about environmental conditions of distributed control system(DCS) to be tested, design specifications of the system, recommended conditions of relative IEC-STD and applied conditions of similar company. ESS test was applied at the DCS to be installed in power plant. As the results of analyzing discovered problems. It was found that almost latent defects of electronic control systems was discovered early.

• Journal of Korean Society for Quality Management
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• v.43 no.3
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• pp.273-288
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• 2015

Purpose: In this study, we apply environmental stress screening (ESS) to battle management system (BMS) of a tank and use the ESS profile based on production process data, guided by MIL-HDBK-781/344/2164. Methods: To optimize ESS Profile of the BMS of a tank, we estimate ESS model parameters (e.g., defect density, screening strength) using primary production failure reporting and corrective action system (FRACAS) data of military supply contract firm. Results: First, we collect the Primary production FRACAS data of military supply contract firm. Second, we compute curve fitting approach to find patent defect density and latent defect density using FRACAS data. Third, we solve the equation of Defect Density(patent defect density + latent defect density)($D_{IN}$) and Screening Strength(SS) Using second step data. As a result of analysis according to the order, we calculate $D_{IN}$(Temperature stress case : 74.02, Vibration stress : 10.252) and : SS(Temperature stress case : 0.4632, Vibration stress : 0.4142) and confirm the Condition II-D based on MIL-HDBK-344. According to Condition II-D, it is necessary to modify existing ESS profile through decreasing the $D_{IN}$ and increasing the SS. Conclusion: Identification of defect causes through ESS approach reduce defect densities for production. It provides feedback to a lessons-learned data base to avoid similar problems on next generation tank BMS.

• Proceedings of the Korean Reliability Society Conference
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• 2001.06a
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• pp.273-275
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• 2001

With the continuous advancement in electronics technology, especially the usage of new materials and the introduction of new and immature manufacturing process, stress and time dependent types of physical, chemical and mechanical imperfections are introduced to the electronic hardware. These types of imperfections are called flaws. A reliability stress screening process(RSS) is a process which involves the application of operational and/or environmental stress to electronic hardware on a 100% basis, for the purpose of precipitating inherent, as well as process-induced, flaws while neither destroying nor degrading in a significant way the hardware being stressed.

• Journal of Applied Reliability
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• v.18 no.3
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• pp.229-239
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• 2018

Purpose: There is a difficulty in Environmental Stress Screening (ESS) test design for weapon system's electrical/electronic components/products in small and medium-sized enterprises. To overcome this difficulty, I propose an easy ESS test design approach algorithm that is optimized with only one environment tolerance design information parameter (${\Delta}T$). Methods: To propose the mass production weapon system ESS test design for cost-effective optimization, I define an optimum cost-effective mathematical model ESS test algorithm model based on modified MIL-HDBK-344, MIL-HDBK-2164 and DTIC Technical Report 2477. Results: I clearly confirmed and obtained the quantitative data of ESS effectiveness and cost optimization along our ESS test design algorithm through the practical case. I will expect that proposed ESS test method is used for ESS process improvement activity and cost cutting of mass production weapon system manufacturing cost in small and medium-sized enterprises. Conclusion: In order to compare the effectiveness of the proposed algorithm, I compared the effectiveness of the existing ESS test and the proposed algorithm ESS test based on the existing weapon system circuit card assembly for signal processing. As a result of the comparison, it was confirmed that the test time was reduced from 573.0 minutes to 517.2minutes (9.74% less than existing test time).

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2003.05a
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• pp.66-67
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• 2003

• Journal of Advanced Navigation Technology
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• v.25 no.5
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• pp.313-319
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• 2021

In this paper, the ESS test based on the MIL-HDBK-344A is introduced, and the purpose of the ESS test of the guided missile internal cable, and the specification and test method are confirmed. The ESS test configuration consists of environmental stimulation of temperature circulation and random vibration. Based on the procedure in the handbook, the ESS test specification setting and test configuration of the guided missile internal cable are presented, and the jig for the ESS test of the guided missile internal cable for the vibration test was produced. The probability of detecting a defect determined through the screening strength(SS) was set to match the reliability of a one-time guided missile, and also introduced the inspection method and considerations for the cable inside the guided missile during the ESS test.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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• pp.66-67
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• 2003

It is well known that osteoblasts and osteoc1asts playa key role in bone metabolism. They involve in osteoformation or bone destruction which are ragulated by various factors such as thyroid hormone, parathyroid hormone, estrogen, growth factor and cytokine. Recently, it is demonstrated that oxidative stress is one of pathological factors in bone metabolism, but it is left unknown about mechanism between oxidative stress and bone metabolism.(omitted)

• BMB Reports
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• v.41 no.3
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• pp.259-265
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• 2008

Three peroxidase (POD) cDNAs were isolated from dehydration-treated fibrous roots of sweetpotato (Ipomoea batatas) plant via the screening of a cDNA library, and their expressions were assessed to characterize functions of each POD in relation to environmental stress. Three PODs were divided into two groups, designated the basic PODs (swpb4, swpb5) and the anionic PODs (swpa7), on the basis of the pI values of mature proteins. Fluorescence microscope analysis indicated that three PODs are secreted into the extracellular space. RT-PCR analysis revealed that POD genes have diverse expression patterns in a variety of plant tissues. Swpb4 was abundantly expressed in stem tissues, whereas the expression levels of swpb5 and swpa7 transcripts were high in fibrous and thick pigmented roots. Swpb4 and swpa7 showed abundant expression levels in suspension cultured cells. Three POD genes responded differently in the leaf and fibrous roots in response to a variety of stresses including dehydration, temperature stress, stress-associated chemicals, and pathogenic bacteria.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.2
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• pp.335-342
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• 2020

ESS(Environmental Stress Screening) is an important production process to remove 'latent defects' introduced in the production of products. Recently, ESS is included in QAR(Quality Assurance Report) as an essential quality assurance requirement for products in the defense business. However, depending on the author of the QAR or the classification of the weapon system, it is often identified that the content and form are different or important elements are omitted. Therefore, this paper proposes a MIL-HDBK-344A based quantitative ESS requirement standard to secure the consistency and completeness of QAR. and to make easier to calculate PE(Precipitation Efficiency), which is an indicator for identifying the latent defects elimination effect.