• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.47 no.5
• /
• pp.319-325
• /
• 2019

The main purpose of this study is to compare the bird strike analysis result of the radome composed of composite laminate and sandwich structure attached to aircraft with test result. First of all, we generated bird model which has water properties through SPH(Smoothed Particle Hydrodynamics) method. And then bird strike analysis was conducted with initial velocity of bird measured from bird strike test. From analysis result we investigated whether structural failure occurred or not onto the radome and compare maximum displacement of the radome structure with test result. Also reliability of numerical analysis model was confirmed through time-dependent pressure trend on this collision process matched existing research result. Furthermore, we confirmed that failure behavior of the radome can be affected by density of the particles in the bird model.

• Journal of the Korean Geotechnical Society
• /
• v.16 no.1
• /
• pp.157-165
• /
• 2000

The applicability and performance of HMS-25 as the railroad roadbed materials were evaluated through the model and laboratory tests. The uniaxial compression test of HMS-25, model soil box test, and combined resonant column and torsional shear test were performed for static and dynamic analysis of railroad roadbed. The uniaxial compression test result of HMS-25 shows steady increase in strength due to hardening chemical reaction between HMS-25 and water. The result of model soil box test reveals that railroad roadbed of HMS-25 is better than that of soil in several aspects such as bearing capacity and settlement. The combined resonant column and torsional that shear test result indicates that shear modulus of HMS-25 increases with the power of 0.5 to the confining pressure and that shear modulus increases with the increase of curing period.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.58 no.2
• /
• pp.45-52
• /
• 2016

The object of this paper was to evaulate modified proposed design equation in model test result in order to estimate uplift-resistance of timber pile of reclaimed land greenhouse foundation. Uplift resistance result of model test was increased to according to increased of contact area. Uplift-resistance result of field test tend to lineary increased to according to increased of embedment depth and contact area. Results of field uplift-resistance was evaluate compare with modified proposed design equation results of model test and Effective stress method. As the Effective stress method tend to underestimate, modified proposed design equation results of model test tend to similar type. As the contact area increase, difference between field uplift-resistance results and modified proposed design equation results of model test was considered uplift-speed.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1999.10a
• /
• pp.759-762
• /
• 1999

The concrete structures possessing good structural integrity can face durability problems due to deteriorations of concrete structures under various environmental conditions. The durability problems weaken the structural integrity in the long run. Especially, the excessive use of sea sand causes serious reinforcement corrosion and carbonation in concrete structures. An accelerated test is often used to predict deterioration as a qualitative measure, but without long term exposure test results or understanding of the relationship between the accelerated test and the long term exposure test, the accelerated test result alone can not be used effectively as a quantitative measure. In this paper, a methodology is proposed to predict the long term deteriorations, based on the result of the short-term accelerated test, of concrete containing different contents of chloride ions. Then, the correlation between two results on the steel corrosion ratio and the carbonation depth is analyzed for concrete with different chloride contents.

• Journal of Engineering Education Research
• /
• v.16 no.4
• /
• pp.15-20
• /
• 2013

The result of the English test for freshmen showed wide difference in the ability of students, which means the graded class is strongly required. This paper describes the case study about the graded English class that was carried out for the freshman. Every freshman must take an English placement test from problems bank and were classified according to the result of the test. In order to resolve the dissatisfaction of the high level students, the statutes of my university for credit were modified. In order to analyze the effect of the graded class, evaluation test using similar problems was carried out at the end of the semester. The effect of the graded class was analyzed by using the paired samples t-test method and there was a meaningful performance improvement at the average score. Additional improvements in the method of classification and credit granted were made by analyzing the results of the evaluation test and survey.

• Korean journal of food and cookery science
• /
• v.9 no.2
• /
• pp.78-81
• /
• 1993

"Yut Kang Jung" is a kind of Korean traditional cookie. The purpose of this study is to examine the effects of various kinds of syrups and cooking methods of Yut Kang Jung. The quality of Yut Kang Jung was evaluated by sensory and Instron machine test. The results is as follows; 1. The Recipe of the best Yut Kang Jung is this: White sesame 120g, sugar syrup 40g, and crude maltose watery 50g are used. Mixing sugar syrup crude maltose watery boiling for 4 min, in temperature $105^{\circ}C$. The sugar density after boiling was 86%. 2. Yut Kang Jung made by sugar syrup and crude watery maltose got the best result in sensory best. 3. Yut Kang Jung made by crude watery maltose got the best result in mechanical test. 4. The comparison between the sensory test & mechanical test were as follow; The hardness in the mechanical test was comparable with hardness & fracturability in the sensory test, and the chewiness in the mechanical test was comparable with flavor, adhesiveness, fractur ability in sensory test.

• Proceedings of the KSR Conference
• /
• 2003.10c
• /
• pp.519-522
• /
• 2003

'KRS 6330-3256라' standard regulates performance test of insulating transformer for protecting the electronic interlock linkage equipment which is being done by test procedures and methods according to the standard. The balance/unbalance test evaluating the performance of transformer are applied by impulse voltage($l2/200{\mu}s$) but affected by many other factors. Therefore, the review about these is necessary to have the reliability and reappearance of test results. In this paper, we have simulated about several phenomenon appearing in real balance/unbalance test and compared simulated results with real ones. With the basis of these results, the influence to test result of inner and outer factors are investigated and analyzed and established the plan boosting the reliability and reappearance of test results.

• The KIPS Transactions:PartD
• /
• v.13D no.4 s.107
• /
• pp.573-582
• /
• 2006

Black-box testing needs to prepare fitting test data, execute software, and examine the result. If we test software effectively, not only selecting test cases but also representing test cases are important. In static testing effectiveness of testing activities also depends on how to represent test cases and checklist to validate. This paper suggests a method for finding ineffective critical test cases and reengineering them. An experiment of reengineering digital set-top box software shows the process and results of checking effectiveness and conformance of current test cases and patching test cases. The result shows how much save the test time and improve test coverage by reengineering test cases. Methods of reuse and restructuring test cases are also studied to fit into embedded product-line software.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.13 no.3
• /
• pp.156-158
• /
• 2009

Purpose: Since radiopharmaceuticals are intended for human administration, it is imperative that we should undergo quality control very strictly. Now almost all the PET laboratories have adopted Bacterial Endotoxin Test as the stand quality control method to monitor whether pyrogen is free or not in the product vial containing crude solution. The aim of this study is to find out the reason why false positive result is observed when using commercially available test vial. Materials and Methods: For this experiment, we used commercially available single test kit (Associates of Cape Code. Inc. USA) and we made pH samples by mixing each buffer whose pH ranges are 1.0 to 12.0. Otherwise we made Ethanol samples diluted with distilled water. After making test samples, it added 0.2 mL to the test vial. Assay mixture in the test vial was incubated in a water bath (Chang Shin Co. KOR) for 60 min at $35{\pm}2^{\circ}C$. Results: After incubation period ($60{\pm}1^{\circ}C$), we inverted the test vial about $180^{\circ}$ To know what pH and how many percentage of Ethanol (Fisher Scientific Korea. Ltd) will affect the reaction. With pH buffer, false positive result was observed at pH 1.0 to 5.0 and 7.7 to 12.6 but at pH 5.2 to.7.5, the test results show negative. It's very strange that we couldn't observe negative test result with Tris buffer at pH 8.4, 8.6, 8.8, 9.0. in other case Ethanol, the test result was seen with 5 to 10% Ethanol. But to my surprise we could see very thick gel formation with 100% Ethanol. Conclusions: In this study, we could notice that pH which is too much acidic or alkalic or high concentrated Ethanol would affect Bacterial Endotoxin Test result. As you know, LAL test is sensitive and very reliable method. Therefore, we are needed to elicit the accurate test result as possible as we can.

• Journal of the Korean Institute of Gas
• /
• v.21 no.6
• /
• pp.15-22
• /
• 2017

The pressure safety valve is very important device for securing the safety in the facilities which is operated by high pressure gases. The performance test should be periodically inspected by relate law because the failure of pressure safety valves might be main causes of serious accidents in the industrial fields. Shop test is mainly use for inspecting the performance test of pressure safety valves but the test method is not to be a solution for securing the safety. So, the development of alternative method is required. In this paper, there is a limit to securing the safety if the performance test is with just shop test. The limitation is checked from analysis result based on performance test results of pressure safety valves. The necessity for introducing the in-service test is reviewed to surmount the limitation. As a result, in-service test method should be developed and introduced to improve the inspection efficiency and economical loss. Also, it can be reduce the risk level.