• The Korean Journal of Food And Nutrition
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• v.27 no.2
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• pp.213-218
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• 2014

The enterotoxin production and antimicrobial susceptibility on hemolytic strains from stools of diarrheal pigs was investigated in this study. Through morphological observation, gyrB nucleotide sequence, and API kit analysis, the selected potential pathogenic strain BY06 was identified as Bacillus cereus. Because the characteristic of enterotoxin symptoms were widely caused by Bacillus cereus strains, a PCR test was carried out in order to check the enterotoxin genes (hblA) in this strain. According to the results, this strain was an enterotoxin positive strain containing the hblA gene. The minimum inhibitory concentrations of 10 different antimicrobial agents were screened by the agar dilution test, indicating that this strain was resistant to penicillin G and intermediate to erythromycin; however, it susceptible to cephalothin, vancomycin, clindamycin, fusidic acid, gentamicin, ciprofloxacin, tetracycline and rifampin. These results suggest that the B. cereus BY06 isolated from pig feces has a potential risk of producing enterotoxin and is resistant to penicillin G, but susceptible to various antimicrobial agents.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.4
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• pp.233-240
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• 2019

Open-hole tensile tests are usually performed to measure the tensile strengths of composites as they are an essential parameter for designing composite structures. However, correctly modeling the tensile test is extremely challenging as it involves various damages such as fiber and matrix damage, delamination, and debonding damage between the fiber and matrix. Therefore, a progressive damage model was developed in this study to estimate the in-plane failure and delamination between the fiber and matrix. The Hashin damage model and cohesive zone approach were used to model ply and delamination failures. The results of the present model were compared with previously published experimental and numerical findings. It was observed that neglecting delamination during finite element analysis led to overestimation of tensile strength.

• The Journal of the Korean Society for Microbiology
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• v.1 no.1
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• pp.10-11
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• 1958

• Journal of the Korean Institute of Telematics and Electronics
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• v.21 no.1
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• pp.57-61
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• 1984

This paper deals with the selection of minimal test instruction set for microprocessor data processing test. This test method is based on a function description of the instructions which are obtained from the data given by the user's manual. Selecting procedure is done in 3 steps: 1) a test execution graphs are represented on the instructions which are grouped functionally, 2) the essential graphs, the eliminable graphs, the eliminable graphs, and the eligible graphs are built, 3) optimal test instruction set from the essential graphs and the eligible graphs is defined. In the case of INTEL 8048, 50 test instructions can be selected optimally from 8048 instruction repertories (96 instructions)

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.10a
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• pp.189-192
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• 2004

Test Facility for hot firing test of small size liquid rocket engine has been developed to research the cooing characteristics of kerosene for cylinder part especially. Propellants for the tests are kerosene and liquid oxygen as fuel and oxidizer respectively and they are fed by gaseous nitrogen. The engine components used hot firing test except for cylinder are cooled by tap-water. Valves for supply of propellants and coolants are controlled by pneumatically. System control and data recording are conducted automatically.

• Composites Research
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• v.14 no.1
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• pp.1-7
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• 2001

In this study, damage evaluation of glass fiber reinforced thermoplastic composites was investigated with acoustic emission method. Specimens of 1.7mm thickness laminate were made from PET and 7 layers o171ass fabrics. Notch and impact loading were added to the specimen and normal tensile test and tensile test with the dead load were carried out. AE signal was measured as the functions of notch ratio to the width0 and impact energy in order to find out the correlation between fracture mode and AE parameters. The result has shown that low amplitude of AE signal was due to the microcrack of matrix and its growth, whereas the amplitude in the mid range was the response to the delamination and interfacial separation. In the range of high amplitude above 90dB. the fracture of glass fabric was found. Tensile strength decreased with increasing notch ratio to the width and impact energy because of tile effect or delamination, the cracking of matrix and stress concentration. In proportion to the size of damaged area. AE signal showed its wider range of frequency and energy as well as increased number of hits.

• The Korean Journal of Mycology
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• v.18 no.2
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• pp.96-101
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• 1990

This study was conducted to select the promising antifungal microoganisms for biological control of wet bubble, Mycogone perniciosa. Ninty one isolates of fungi, 342 isolates of bacteria, and 556 actinomycetes were isolated from mushroom composts and soils, were subjected to primary screening test on agar medium base for their antimicrobial spectra. Among them, 12 bacteria and 71 actinomycetes were selected. Among the antibiotic producing microoganisms, 5 cultures were selected on the basis their antibiotic activities on casing soil with Benlate nontolerence M. perniciosa. Finally, AJ-117, AJ-136 and AK-139 were selected as microoganism with antifungal activity against two strains of M. perniciosa.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.9
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• pp.714-719
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• 2013

A turboprop aircraft for this study is required to operate at icing condition in order that it performs its given mission. So an air intake system of the turboprop aircraft should be designed and verified not only to provide the maximum possible total pressure at engine inlet at normal flight condition, but also to include an inertial separator which protects Foreign Object Debris (FOD) like ice or snow at icing condition from entering into the engine inlet screen which can cause or lead an catastrophic engine failure like engine flame-out or severe damage. So an air intake assembly incorporating a variable geometry inertial separator has been designed and then CFD/structural analysis for the assembly was performed to see its design results. Then 35% scaled model of the air intake assembly was manufactured and wind tunnel test was done. This paper describes the detailed design results for the aerodynamic design, analysis and wind tunnel testing during the development process of the air intake assembly.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.577-580
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• 2008

This paper was discussed about in-site application of heavyweight(or high density) concrete. Heavyweight concrete was placed with the method of conventional. Placement of conventionally mixed heavyweight concrete is subject to the same considerations of quality control as normal density concrete, except that it is far more susceptible to variations in quality due to improper handling. It is particularly subject to segregation during placement. Segregation of heavyweight concrete results not only in variation of strength but, far more importantly, in variation in density that are intolerable for work this type, since this adversely affects shielding properties. Heavyweight concrete materials and heavyweight concrete should be sampled and tested prior to and during construction to insure conformance with applicable standards and specifications.

• Korean Journal of Poultry Science
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• v.18 no.3
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• pp.141-150
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• 1991

A local isolate of chicken anemia agent (CAA), isolate 89-69. was tested for pathogenicity for chickens. When chickens from a specific pathogen free (SPF) flock were inoculated intramuscularly with the isolate at one day old, all the chickens showed severe anemia at 14 to 18 days post inoculation(DPI) and returned to normal at 25DPI, Some of the inoculated chickens (27∼33％) died between 13 to 17 DPI's with lesions of severe aplasia of bone marrow and thymic atrophy. In chickens kept in contact with inoculated chickens, some of the chickens had anemia at 25 and 28 DPI's. Virus could be reisolated from inoculated as well as in contact chickens till 21 DPI. Antibodies to CAA could be detected in all inoculated and in contact chickens when tested at 42 DPI by the indirect fluorescent antibody method. When chickens from a different SPF flock were inoculated at one day old, degrees of anemia, both in frequency of incidence and severity, were low These chickens were proved partly to have antibodies to CAA when tested for hatchmates. In a survey for antibodies to CAA in field chicken flocks, one out of 7 flocks(14％) aged 3 to 10weeks was antibody positive whereas 19 out of 20 flocks(95％) over 20 weeks of age were positive. Altogether 29 out of 39 flocks (74％) were antibody positive.