• Journal of Aerospace System Engineering
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• v.15 no.4
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• pp.40-46
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• 2021

At launch, satellites are exposed to various types of structural loads, such as quasi-static loads, sinusoidal vibrations, acoustic/random vibrations, and shocks. The launch environment test is aimed at verifying the structural stability of the test object against the launch environment. Various types of launch environments are simulated by simple vibration, acoustic, and shock tests considering possible test conditions in ground. However, the difference between the launch environment and the test environment is one of the causes of excessive testing. To prevent overtesting, a notching technique that adjusts the frequency range and the input load considering the design load is applied. For notching, specific procedures are established considering the satellite development concept, selected launch vehicle, higher system requirements, and test target level. In this study, the notching method, established procedure, and development of a notching toolkit for efficient testing are described.

• Quality Improvement in Health Care
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• v.30 no.1
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• pp.105-119
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• 2024

Purpose: This study aimed to develop a survey instrument to assess the Patient Safety Culture in Korean hospitals and evaluate its validity and reliability. Methods: A preliminary instrument was developed through a literature review, focus group interviews, content validity testing, and pretesting for face validity. A total of 467 hospital employees participated in the psychometric testing. Validity and reliability assessments included content validity, construct validity, criterion-related validity, and internal consistency. Results: The Korean Patient Safety Culture Survey Instrument comprised 35 items across seven factors: leadership, patient safety policy and procedure, patient safety improvement system, teamwork, non-punitive environment, patient safety knowledge and attitudes, and patient safety priority. These seven factors contributed 60.98% of the variance of the total scale. Cronbach's alpha for internal consistency was .93; the seven factors ranged from .66 to .91. Conclusion: The results of this study showed that the Korean Patient Safety Culture Survey Instrument is reliable, valid, and suitable for measuring patient safety culture in Korean hospitals.

• ETRI Journal
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• v.26 no.6
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• pp.520-534
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• 2004

As the density of memories increases, unwanted interference between cells and the coupling noise between bit-lines become significant, requiring parallel testing. Testing high-density memories for a high degree of fault coverage requires either a relatively large number of test vectors or a significant amount of additional test circuitry. This paper proposes a new tiling method and an efficient built-in self-test (BIST) algorithm for neighborhood pattern-sensitive faults (NPSFs) and new neighborhood bit-line sensitive faults (NBLSFs). Instead of the conventional five-cell and nine-cell physical neighborhood layouts to test memory cells, a four-cell layout is utilized. This four-cell layout needs smaller test vectors, provides easier hardware implementation, and is more appropriate for both NPSFs and NBLSFs detection. A CMOS column decoder and the parallel comparator proposed by P. Mazumder are modified to implement the test procedure. Consequently, these reduce the number of transistors used for a BIST circuit. Also, we present algorithm properties such as the capability to detect stuck-at faults, transition faults, conventional pattern-sensitive faults, and neighborhood bit-line sensitive faults.

• Journal of the Korean Society for Nondestructive Testing
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• v.21 no.6
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• pp.612-617
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• 2001

A nondestructive evaluation technique for detecting internal defects of an hot forged Al-Si alloy part is established in this study. Ultrasonic characteristics of various internal planar defects are investigated by experiments for establishing a reliable test procedure. The effect of the angle between ultrasonic energy propagation directions and planar defects on the ultrasonic signal configuration is evaluated in the pulse-echo technique. A characteristic of ultrasonic signal for the internal planar defect located near the edge is also evaluated. The applicability of the through-transmission technique is also discussed. Reliability of the presented approach is validated by the destructive testing for more than 500 specimens.

• Journal of Ocean Engineering and Technology
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• v.21 no.2 s.75
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• pp.60-66
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• 2007

The first Korean cold room facility for ice mechanics experiments was assembled in 2004. Since then, the $4m{\times}6m$ cold room facility has been used, extensively under various environmental and loading conditions. After reviewing published references on cold room testing methods and also by trial and error, the standard procedures for testing and preparing laboratory ice material were established for the measurement of basic ice properties. In this paper, laboratory experimental techniques with the cold room facility and standard procedures established for ice material properties are introduced. Test specimens include laboratory-grown fresh water ice and frozen soils. Tests are carried out for unconfined compressive strength. Preparation and dimension of the specimen are the most important issues arising in cold room tests. The details of specimen preparation, testing procedure and strength test results are also discussed.

• The Journal of Korean Physical Therapy
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• v.26 no.5
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• pp.344-350
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• 2014

Purpose: The purpose of this study was to translate and culturally adapt the International Classification of Functioning, Disability and Health (ICF) into the Korean language. Methods: The process of translation and adaptation of the ICF used here followed the translation guidelines of WHO. Implementation of this procedure comprised of four steps; forward translation, expert panel back-translation, pre-testing and cognitive interviewing, and final adaptation. The translators included health professionals with knowledge of ICF and non-health professionals blinded to the ICF. Clinical academics with significant experience in the use of disability survey, medical doctors, special educators, related policy makers, clinicians, architecture professionals, and international experts in ICF were invited to integrate all versions of the ICF for testing; 151 clinicians volunteered from 19 medical institutes across the country. Four different core-sets and a questionnaire were used for testing its practical usability and adaptation. Results: All translations were reviewed and a consensus was reached on any discrepancy from the earlier versions. Over 90% of the newly translated version of K-ICF was found to be different from the 2004 K-ICF version in the ICF language. Understanding of K-ICF language was responded difficult and very difficult by 50% of participants, whereas its practical use was responded 'useful' by more than 50% of subjects. Conclusion: It can be suggested that the new version of K-ICF should be widely used for final adaptation in the field of areas. Future studies will be required for implementation of K-ICF.

• Structural Engineering and Mechanics
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• v.17 no.3_4
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• pp.429-444
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• 2004

The ambient vibration measurement is a kind of output data-only dynamic testing where the traffics and winds are used as agents responsible for natural or environmental excitation. Therefore an experimental modal analysis procedure for ambient vibration testing will need to base itself on output-only data. The modal analysis involving output-only measurements presents a challenge that requires the use of special modal identification technique, which can deal with very small magnitude of ambient vibration contaminated by noise. Two complementary modal analysis methods are implemented. They are rather simple peak picking (PP) method in frequency domain and more advanced stochastic subspace identification (SSI) method in time domain. This paper presents the application of ambient vibration testing and experimental modal analysis on large civil engineering structures. A 15 storey reinforced concrete shear core building and a concrete filled steel tubular arch bridge have been chosen as two case studies. The results have shown that both techniques can identify the frequencies effectively. The stochastic subspace identification technique can detect frequencies that may possibly be missed by the peak picking method and gives a more reasonable mode shapes in most cases.

• Safety and Health at Work
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• v.2 no.3
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• pp.218-228
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• 2011

Objectives: The objective of this study was to test the feasibility and acceptability of a new workers' health surveillance (WHS) for fire fighters in a Dutch pilot-implementation project. Methods: In three fire departments, between November 2007 and February 2009, feasibility was tested with respect to i) worker intent to change health and behavior; ii) the quality of instructions for testing teams; iii) the planned procedure in the field; and iv) future WHS organisation. Acceptability involved i) satisfaction with WHS and ii) verification of the job-specificity of the content of two physical tests of WHS. Fire fighters were surveyed after completing WHS, three testing teams were interviewed, and the content of the two tests was studied by experts. Results: Feasibility: nearly all of the 275 fire fighters intended to improve their health when recommended by the occupational physician. The testing teams found the instructions to be clear, and they were mostly positive about the organisation of WHS. Acceptability: the fire fighters rated WHS at eight points (out of a maximum of ten). The experts also reached a consensus about the optimal job-specific content of the future functional physical tests. Conclusion: Overall, it is feasible and acceptable to implement WHS in a definitive form in the Dutch fire-fighting sector.

• Advances in aircraft and spacecraft science
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• v.2 no.3
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• pp.303-328
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• 2015

A design methodology is presented to develop the hingeless control surfaces for MAV using adhesively bonded Macro Fiber Composite (MFC) actuators. These actuators have got the capability to deflect the trailing edge surfaces of the wing to attain the required maneuverability, besides achieving the set aerodynamic trim condition. A scheme involving design, analysis, fabrication and testing procedure has been adopted to realize the trailing edge morphing mechanism. The stiffness distribution of the composite MAV wing is tailored such that the induced deflection by piezoelectric actuation is approximately optimized. Through ground testing, the proposed concept has been demonstrated on a typical MAV structure. Electromechanical analysis is performed to evaluate the actuator performance and subsequently aeroelastic and 2D CFD analyses are carried out to see the functional requirements of wing trailing edge surfaces to behave as elevons. Efforts have been made to obtain the performance comparison of conventional control surfaces (elevons) with morphing wing trailing edge surfaces. A significant improvement in lift to drag ratio is noticed with morphed wing configuration in comparison to conventional wing. Further, it has been shown that the morphed wing trailing edge surfaces can be deployed as elevons for aerodynamic trim applications.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.27-33
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• 2016

Military textiles with breathable waterproof materials are expanding as form of winter clothes. Waterproof moisture-permeable clothes are very important for soldiers to survive in cold weather operations because they prevent loss of body heat from the penetration of water into the human body. Korea military uses the water resistance and moisture permeability to test the performance of waterproof moisture-permeable materials. Moisture permeability is measured according to the amount of evaporated water vapor passing through a fabric under specified temperature and humidity by using acetic acid potassium presented in KS K 0594. However, the test procedure for measuring the moisture permeability in the standard is presented only briefly and the preparation procedures for the test in accredited testing institutions are applied differently, leading to significant deviation of the results. This paper compares the procedures of testing institutions and examines the factors that affect moisture permeability. Finally, we propose a procedure to reduce the deviation of results and apply the proposed procedure in testing institutions. Our analysis results with one-way ANOVA under significant level (0.05) confirm that the deviation of results is reduced.