• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.47-52
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• 2005

We present a simple idea to simulate dynamic fracture and fragmentation of a propulsion system exposed to an extreme condition, such as a fire. The system consists of energetic materials confined in a steel cylinder. The strain failure model of the confinement is a modified Johnson-Cook model with a statistical failure distribution. By using the size distribution data of the fragments from the thermal explosion tests, the failure strain distribution can be empirically obtained and then entered into the model. The simulated fracture and fragment sizes are compared with the experimental records.

• Journal of Pharmaceutical Investigation
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• v.20 no.3
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• pp.115-119
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• 1990

The reaction rates, duration times and neutralizing capacities of the antacids which are frequently used in Korean market and three different commercial combination products were evaluated in vitro by Fuchs method and Johnson-duncan method, respectively. In vivo tests of combination products were determined in the fasted state of rat by Aspiration method. Comparing the result of in vitro test with that of in vivo test, the maximal pH was lowered by 2-3 value and the durational time increased by two folds in vivo test. Each antacid composition and combination products from three phamaceutical companies (A, B, and C) were studied, respectively. The duration times measured by Fuchs method were double compared to those by Johnson-Duncan method. A and C preparation maintained the pH range from 3 to 7 for 60 min by Fuchs method. In vovo test, maximum pH of A, B and C preparation was 6.50, 3.65, 2.65 and duration time of those was 200, 500, 0 min, respectively.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.56.1-56.1
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• 2016

Surface mineralogy of asteroids are inferred from photometric and spectroscopic observations with the wide range of wavelengths spanning from far-ultraviolet to mid-infrared. We classify mineralogy of those objects based on their spectral absorption features and spectral slopes. Based on overall spectral shapes, mineralogical classes are divided into three broad complexes; silicates (S), carbonaceous (C) and Vestoids (V), and the end-members that do not fit within the S, C and V broad-complexes. Each of them is subdivided into individual classes. Spectral classification of asteroidal objects has been simply represented by a combination of photometric colors. For a decade, photometric data of asteroids have been grouped and classified according to their SDSS colors converted from the spectral taxonomy. However, systematic studies for asteroid taxonomy based on Johnson-Cousins filters is few, and were conducted only with a small number of objects. In this paper, we present our preliminary results for taxonomic classification of Main Belt asteroids based on KMTNet Johnson-Cousins photometric color system.

• Proceedings of the KIPE Conference
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• 2018.07a
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• pp.33-35
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• 2018

본 논문에서는 Quasi-Watkins-Johnson(qWJ) 인버터를 제안한다. 단상 qWJ 인버터는 기존의 Watkins-Johnson(WJ) 인버터에서 간단한 회로 수정을 통해 제안되며, 기존의 WJ 인버터의 모든 장점을 유지한다. 제안한 인버터는 모든 능동 스위치가 비절연형 게이트 구동을 하므로 게이트 구동회로의 부담을 덜어주고 기존 방식에 비해 적은 비용과 작은 크기로 구현할 수 있다. 또한, 제안한 인버터는 기존의 하프-브릿지 인버터의 출력전압보다 더 큰 출력전압을 가진다. 3상 qWJ 인버터는 출력전압이 입력전압의 2배까지 승압이 가능하다. 계통연계형 태양광 시스템에 적용 시, 기존의 3상 전압형 인버터는 누설전류로 인해 안정성에 문제가 생길 수 있지만, 제안한 인버터는 누설전류에 의한 문제가 생기지 않는다. 그러므로 제안한 인버터는 누설전류를 줄이기 위한 추가적인 회로가 필요하지 않고 적은 비용과 작은 사이즈로 계통연계형 태양광 인버터 시스템을 구현할 수 있다. 이러한 장점들은 3상 qWJ 인버터에서 더욱 현저하게 드러난다. 1kW의 시제품을 제작하여 제안한 인버터의 성능을 검증하였다.

• ETRI Journal
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• v.33 no.4
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• pp.621-628
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• 2011

The redactable signature scheme was introduced by Johnson and others in 2002 as a mechanism to support disclosing verifiable subdocuments of a signed document. In their paper, a redactable signature based on RSA was presented. In 2009, Nojima and others presented a redactable signature scheme based on RSA. Both schemes are very efficient in terms of storage. However, the schemes need mechanisms to share random prime numbers, which causes huge time consuming computation. Moreover, the public key in the scheme of Johnson and others is designed to be used only once. In this paper, we improve the computational efficiency of these schemes by eliminating the use of a random prime sharing mechanism while sustaining the storage efficiency of them. The size of our signature scheme is the same as that of the standard RSA signature scheme plus the size of the security parameter. In our scheme, the public key can be used multiple times, and more efficient key management than the scheme of Johnson and others is possible. We also prove that the security of our scheme is reduced to the security of the full domain RSA signature scheme.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.52
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• pp.69-79
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• 1999

The main objective of this study are to propose two methods that would be a comprehensive measure of evaluation for non-normal process capability with Beta distributions. First method is introduced using process capability index $C_{psk}$ by the Pearson system and Johnson system. The Pearson system and the Johnson System selected for process capability index calculation have a equivalent result of this study that the ranking of the seven indices in terms of sensitivity to departure of the process median from the target value from the most sensitive one up to the least sensitive are $C^{*}_{pm}$ , $C_{psk}$ , $C_{s}$ , $C_{pmk}$ , $C_{pm}$ , $C_{pk}$ , $C_{p}$ . Second method show using the percentage nonconforming by the Pearson, Johnson and Burr functions. In thus study, we find that the Pearson system and the Burr system are a reasonable method to estimate percentage nonconforming. But, the exact procedure for deriving this estimate will be based on Beta distribution. Accordingly, if a process is not normally distributed , but normal-based techniques are used serious errors can result.

• Journal of Korean Academy of Nursing
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• v.16 no.2
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• pp.36-43
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• 1986

The main purpose of this study was to explore the effect of the stress of hospitalization on the sleep pattern. Additionaly, this study was also to demonstrate how Johnson's nursing model may be applied to as nursing process. 104 hospitalized patients on surgical and medical wards were asked to rate 49 stress producing events associated with experience of hospitalization and sleep pattern scale. Five university hospitals were used as the setting for this study. Data for the study were collected by patient interview during hospitalization, self-reports and review of charts. For the analysis of the data, the pearson's correlation analysis of covariance and regression analysis were used. The results of this study were stated as follows; 1. The mean of the hospital stress scores was 111.261(S.D.=26.160). This means that the level of the hospitalization stress is high. The mean of the sleep pattern scores was 12.204(S.D. =2.615) This means that the characteristic's of the sleep pattern is poor. 2. The relationship between the hospitalization stress and sleep pattern was statistically significant at .01 level. 3. The effect of the hospitalization stress influenced strongly on the sleep pattern after sex, trait anxiety as covariates controlled. 4. The hospitalization stress revealed a 12% pre-diction as an influenced factor for the sleep pattern. Therefore, It can he said that the hospital stress did contribute significantly to the characteristics of the sleep pattern. Johnson's model can he also said that it is useful for the the assessment and diagnosis in nursing process.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.7
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• pp.465-470
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• 2022

This paper studied the high-velocity impact behavior characteristics of metal materials by crosschecking the high-velocity impact analysis with the high-velocity impact experiment results of aluminul 6061. The coefficients of the Huh-Kang material model and the Johnson-Cook fracture model were calculated through quasi-static using MTS-810 and dynamic experimenting using the Hopkinson bar equipment for high-velocity impact analysis. The penetration velocity and shape were predicted through high-velocity impact analysis using the LS-DYNA. The resultes were compared with the experiment results using a high-velocit experiment equipment. It is intended to be used the containment evaluation research for aircraft gas turbine engine blade.

• Genomics & Informatics
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• v.21 no.2
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• pp.26.1-26.9
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• 2023

Stevens-Johnson syndrome (SJS) produces a severe hypersensitivity reaction caused by Herpes simplex virus or mycoplasma infection, vaccination, systemic disease, or other agents. Several studies have investigated the genetic susceptibility involved in SJS. To provide further genetic insights into the pathogenesis of SJS, this study prioritized high-impact, SJS-associated pathogenic variants through integrating bioinformatic and population genetic data. First, we identified SJS-associated single nucleotide polymorphisms from the genome-wide association studies catalog, followed by genome annotation with HaploReg and variant validation with Ensembl. Subsequently, expression quantitative trait locus (eQTL) from GTEx identified human genetic variants with differential gene expression across human tissues. Our results indicate that two variants, namely rs2074494 and rs5010528, which are encoded by the HLA-C (human leukocyte antigen C) gene, were found to be differentially expressed in skin. The allele frequencies for rs2074494 and rs5010528 also appear to significantly differ across continents. We highlight the utility of these population-specific HLA-C genetic variants for genetic association studies, and aid in early prognosis and disease treatment of SJS.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.66.4-67
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• 2020

Gyeonggi science high school for the gifted (GSHS) installed 60cm telescope, which is waiting for student observers. It is essential to understand the characteristics of the photometric system, consisting of telescope, filter, and CCD, to get reliable data. CCD images of SA98 Landolt standard field and M67 were obtained on 19th March 2020. The images of each field were combined by filters, i.e., we ignored the monochromatic atmospheric extinction since the photometric objects themselves are standard stars. 24 standard stars in SA98 field and 12 standard stars in M67 were used to derive the tentative transformation equation between our bv photometric system and Johnson BV photometric system. In this poster, we present the preliminary standardization result for Johnson BV photometric system in GSHS 60cm telescope. The reproductivity is discussed by comparing color coefficients of two fields. We plan to extend this process to Johnsons-Cousins BVRI photometric system and narrow-band filters for flux calibration.