• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.803-808
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• 2001

Mathematical basis of interpretation of data from nondestructive evaluation (NDE) methods in bridge inspection is presented. In bridge inspection with NDE methods, NDE data are not assessments. NDE data must be interpreted as condition of element. Interpretation is then assessment. Correct assessments of conditions of bridge elements depend on the accuracy and variability in test data as well as on the uncertainty of correlations between attributes (what is measured) and conditions (what is sought in the inspection). Inaccuracy and variability in test data defines the qualify or NDE test. The qualify or test itself is important, but in view of condition assessment, the significance of uncertainty in correlations of attributes and conditions must be combined. NDE methods that are accurate in their measurements may still be found to be poor methods if attributes are uncertain indicators of condition of bridge elements. This paper reports mathematical presentation of inaccuracy and variability in test data and of uncertainty in correlation of attributes to element conditions with three examples of NDE methods.

• Journal of Welding and Joining
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• v.35 no.2
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• pp.63-70
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• 2017

As the Non Destructive Test (NDT) for the welded structure, PT(Penetration Test). MT(Magnetic Test), RT (Radioisotope Test) and UT(Ultrasonic Test) methods are widely used in practice. These NDT methods have been developed toward high efficiency, low cost, real time, and high precise new NDT. For example, RT methods are developed to CT(Computed Tomography)and DR(Digital Radiography), and UT metheds are developed into Phased array, Guide wave, TOFD method. Moreover, the Infrared thermography and Laser ultrasonic technique are newly developed for applying in high temperature objects as the non-contact NDT methods. In this review paper the new high efficiency NDT methods for the welded structure are introduced and the trend of NDT rules applying in welded structure are described.

• Computers and Concrete
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• v.20 no.1
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• pp.39-47
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• 2017

In this paper, mode I fracture toughness of rock was determined by direct and indirect methods using Particle Flow Code simulation. Direct methods are compaction tension (CT) test and hollow centre cracked quadratic sample (HCCQS). Indirect methods are notched Brazilian disk (NBD) specimen, the semi-circular bend (SCB) specimen, hollow centre cracked disc (HCCD), the single edge-notched round bar in bending (SENRBB) specimen and edge notched disk (END). It was determined that which one of indirect fracture toughness values is close to direct one. For this purpose, initially calibration of PFC was undertaken with respect to data obtained from Brazilian laboratory tests to ensure the conformity of the simulated numerical models response. Furthermore, the simulated models in five introduced indirect tests were cross checked with the results from direct tests. By using numerical testing, the failure process was visually observed. Discrete element simulations demonstrated that the macro fractures in models are caused by microscopic tensile breakages on large numbers of bonded discs. Mode I fracture toughness of rock in direct test was less than other tests results. Fracture toughness resulted from semi-circular bend specimen test was close to direct test results. Therefore semi-circular bend specimen can be a proper test for determination of Mode I fracture toughness of rock in absence of direct test.

• Computers and Concrete
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• v.11 no.4
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• pp.305-316
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• 2013

This paper aims to study the effect of measurement methods and cracking on chloride transport of concrete materials. Three kinds of measurement methods were carried out, including immersion test, rapid migration test and steady-state migration test. All of these measurements of chloride transport show that chloride ion diffusion coefficient decreased with the reduction of water to cement ratio. Results of the immersion test were less than that of rapid migration test and steady-state migration test. For the specimen of lower water to cement ratio, the external electrical field has little effect on chloride binding relatively. Compared with the results obtained by these different measurement methods, the lower water to cement ratio may cause smaller differences among these different methods. The external voltage can reduce chloride binding of concrete, and the higher electrical field made a strong impact on the chloride binding. Considering the effect of high voltage on the specimen, results indicate that results based on the steady-state migration test should be more reasonable. For cracked concrete, cracking can accelerate the chloride ion diffusion.

• Korean Journal of Pharmacognosy
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• v.40 no.2
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• pp.155-160
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• 2009

The reference herbal extracts and their identification methods by Korean Pharmacopoeia IX were established based on the organic solvent extracts to detect their marker compounds. However, most of herbal medicine decoctions in the market are prepared with water as extracting solvent. As the reference herbal extracts and their identification methods are not appropriate for the practical test, new preparation of alternative reference herbal extracts and their identification test methods are essential for the correction of test methods and identification of herbal drugs. Three novel identification test methods were developed for Evodiae Fructus, Cimicifugae Rhizoma and Aurantii Fructus Immaturus. Total 10 reference herbal extracts and their identification methods were optimized for Ephedrae Herba, Schisandrae Fructus, Curcuma longae Rhizoma, Citri Unshius Pericarpium, Puerariae Radix, Corni Fructus, and Cinnamomi Cortex.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.141-148
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• 2009

The purpose of this paper is to propose a standard test methods of resistance to root penetration for waterproofing and rootproofing membrane using green roof system. Green roof system is considered to be an important subject in construction industry for green growth project. At the same time, we have to consider the counterplan for protection the damage of waterproofing layer and concrete substrate from the penetration of plant root. But many kinds of materials for protection from root penetration are using in construction field. But the performance of those materials is not clear, and there is not test methods for the evaluation of performance. So in this paper, based on the research results of 4 institutes during four years and foreign cases, we made a standard test methods of resistance to root penetration for waterproofing and rootproofing membrane using green roof system. This test method deals with about environmental condition of laboratory, experimental facilities, kinds of plant, specimen of test, management methods, evaluation duration and documents, etc.

• Asian Journal of Turfgrass Science
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• v.3 no.1
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• pp.13-15
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• 1989

In oder to find out the effective seed germination testing method to the field emergence, an experiment was conducted ; 1. TTC testing results were higher percentage than any other germination testing methods . 2. On the corn seed , field emergence was highly correlated with germinator test, TTC test and AA test hut cold test was lower percentage . 3. Field emergence , on the soybean seeds was highly correlated with AA test and cold test but germinator test and TTC test was higher percentage .

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.5
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• pp.923-928
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• 2009

The performance analysis and robust control of the interior permanent magnet synchronous motor(IPMSM) greatly depend on accurate value of its parameters. To achieve the high performance of torque control, it is necessary to consider exact inductance values because the inductances are nonlinear parameters of operating the IPMSM. Therefore many different methods have been performed for analysis of the methodology for the exact measurement of synchronous inductances. None of them is considered standard, and accuracy levels of all these methods are also not consistent. Among these experimental methods, the DC current decay test and the vector current control test are ideal for a laboratory environment. In this paper, these two test methods are compared by applying inductances to the IPMSM. The paper analyzes the measured inductances of the two methods and their differences with inductances obtained from the finite element method(FEM).

• Journal of Pharmaceutical Investigation
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• v.33 no.4
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• pp.293-298
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• 2003

This study was attempted to develop the physicochemical ad morphological stability test methods for the cream and lotion formulations among the cosmetic foundations and to provide the guidance for the stability methods with respect to basic emulsions and creams. With these developed stability test methods, we can evaluate the expired date or life time of the available basic cosmetics, especially basic lotions ad creams. Also, the stability test methods established in this study can be used as a guideline to test physical and morphological stability of cosmetics in the future. Thus, we selected two types of basic cosmetics such as lotions and creams made by four different cosmetic companies ad applied them to the stability test methods depending on the temperature changes such as temperature cycling and freezing-thawing cycling test. After the temperature changes, the conductivity, turbidity, particle size, creaming ratio and pH changes of the creams and lotions were evaluated and morphological changes such as crystal formation, odor, color and feeling of the creams and lotions were also tested. As the results of the stability tests, all the tested creams and lotions except for one lotion were stable. Therefore, it may be concluded that these short-term accelerated stability tests as physical stability test depending on the temperature change study were suitable for the stability testing methods for the basic cosmetics and may be useful for the establishment of the guideline for the stability test of cosmetics.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.32 no.1
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• pp.11-19
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• 2009

A number of trend test methods, i.e., Military Handbook test and Laplace test etc., have been applied to investigate recurrent failures trend in repairable systems. Existing methods provide information about only existence of trend in the system. In this paper, we propose a new change-point test based on the Schwarz Information Criterion(SIC). The change-point approach is more informative than other trend test methods in that it provides the number of change-points and the location of change-points if it exists, as well as the existence of change-point for recurrent failures. The change-point test is applied to nine 300MW generating units operated in East China. We confirm that the change-point test has a potential for establishing optimal preventive maintenance policy by detecting change-point of failure rate.