• Journal of Oral Medicine and Pain
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• 제9권1호
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• pp.103-116
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• 1984

Randumly sampled out 157 extracted Korean adult teeth, aged 12 to 79 years, was applicated to estimat the age by Gustafson's method, were evaluated and analyzed in terms of phyological aging change. The results are as follows : 1. It was reconfirmed that there existed comparatively close correlationship between age and score, especially in old age. 2. Korean score had comparatively high level than those of European. 3. In the probability of age edetermination, the estimation error was the most high level in the age of 70~ with ±4.47, and next order was in the age of 10-19 with ±5.20,60-69 with ±5.8,30-39 with ±5.98,50-59 ±6.20,40-49 with ±6.72,20-29 with ±9.28.Mean value was ±8.03. 4. The regression equation is as follows. y=3.55x+8.52(r=8.75) standard deviation σ=±8.03 (y= estimated age x=score) 5. In age determination with those data, needs to estimate slightly lower than caculated age in range of 10-49, and higher in 50-70 for the real age determination.

• Steel and Composite Structures
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• 제4권6호
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• pp.453-469
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• 2004

In this article, a genetic algorithm based optimum design method is presented for non-linear steel frames with semi-rigid connections. The design algorithm obtains the minimum weight frame by selecting suitable sections from a standard set of steel sections such as European wide flange beams (i.e., HE sections). A genetic algorithm is employed as optimization method which utilizes reproduction, crossover and mutation operators. Displacement and stress constraints of Turkish Building Code for Steel Structures (TS 648, 1980) are imposed on the frame. The algorithm requires a large number of non-linear analyses of frames. The analyses cover both the non-linear behaviour of beam-to-column connection and $P-{\Delta}$ effects of beam-column members. The Frye and Morris polynomial model is used for modelling of semi-rigid connections. Two design examples with various type of connections are presented to demonstrate the application of the algorithm. The semi-rigid connection modelling results in more economical solutions than rigid connection modelling, but it increases frame drift.

• 한국전자파학회논문지
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• 제25권11호
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• pp.1156-1163
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• 2014

본 논문에서는 EN50289 규격에 따른 동축케이블의 전달 임피던스 측정을 이용하여 여러 가지 통신 케이블의 차폐 특성을 분석하였다. EN50289 규격에서의 전달 임피던스 측정 방법은 CENELEC(European Committee For Electrotechnical Standardization)에서 규정한 Triaxial 방법이며, IEC Standard 96-1에서 규정한 Triaxial 방법과 달리 측정하고자 하는 동축케이블과 외부 도체의 직경에 관계없이 동축케이블의 전달 임피던스를 측정할 수 있는 장점이 있다. 본 논문에서는 EN50289 규격에 따른 동축케이블의 전달 임피던스 측정장치를 설계/제작하였으며, 이것을 이용한 실험 결과를 통해 측정 시스템의 신뢰할만한 주파수 대역을 결정하였고, 동축케이블의 쉴딩 기법의 차이에서 오는 영향에 대하여 분석하였다. 전달 임피던스 측정 결과, 케이블의 쉴딩 기법에 따라 전달 임피던스의 상당한 차이가 있음을 보였다. 또한, RG-58 통신용 케이블의 전달 임피던스 이론식에 의한 계산값과 측정값의 비교를 통하여 측정된 데이터가 유효함을 보였다.

• 한국토양비료학회지
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• 제35권6호
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• pp.327-334
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• 2002

우리나라 유통상토에 대한 물리적 표준분석법을 설정하기 위한 연구를 실시하였다. 국내 시중에 유통되고 있는 53개 품목의 원예용 상토와 9개 품목의 수도용 상토를 대상으로 설정된 분석법을 적용하여 실험하였다. 입자밀도의 측정은 가스형 피크노메타 (Micromeritics Co. Model 1305)를 사용하면 속도와 정확성 면에서 매우 유리 하였다. 용적밀도는 구미에서 Sandbox법에 의한 용적밀도를 기본으로 하기 때문에 이와 유사한 성적을 얻을 수 있는 다양한 실험을 한 결과, 추다짐법 (Plunger compaction method)이 가장 유의성 있는 측정 방법으로 밝혀졌다. 한편 가스형 피크노메타법에 의한 우리나라 유통상토의 입자밀도는 원예용이 1.93, 수도용이 $2.43Mg\;m^{-3}$로 나타났으며, 추다짐법에 의한 용적밀도는 원예용이 0.22, 수도용이 $1.01Mg\;m^{-3}$로 각각 나타났다.

• 약학회지
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• 제45권6호
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• pp.656-663
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• 2001

The quality of an intravenous immunoglobulin preparation (IVIG) is reflected by the degree of nonspecific activation of complements, the so-called anticomplementary activity (ACA). ACA of aggregates in IVIG was investigated using method by the European Pharmacopoeia and Clq-coated microtiter enzyme-linked immunosorbent assay (ELISA). Both the EP method and the ELISA method showed a dose response curve with the amount of complements bound increasing with the percentage content of aggregates in immunoglobulin standard. The correlation between the two tests was good (r=0.96, r=0.99). However, the correlation was not found when the ACA (EP method) of IVIG product was compared with its aggregate percentage. These results emphasize that the method of aggregate formation affects ACA and that estimation of the percentage distribution of aggregates by HPLC may not reflect ACA. In analysing WIG product for Clq binding activity test with the ELISA, the result by using Protein A-HRP correlated with aggregate percentage (r=0.84). But the correlation decreased (r=0.48) when the result used Protein A-AP(having poorer sensitivity than HRP) was compared with aggregate percentage. As a result, some variation between the two methods, due to differences in assay principles, is to be expected. However, ELISA technique has the advantage in that it is easier to perform, more precise and less subject to reagent variability, and is the more suitable screening method than HPLC analysis.

• Bulletin of the Korean Chemical Society
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• 제29권6호
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• pp.1185-1189
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• 2008

Two HPLC methods such as cefadroxil and cefalexin methods were compared in their performance for the quantitative analysis of the content and purity of $\beta$ -lactamic antibiotic, cefradine, for six bulk drug samples. Between the two methods, the cefadroxil method prescribed by the European Pharmacopoeia (EP) for the determination of impurities in cefradoxil was superior to the cefalexin method prescribed by the EP and by the United States Pharmacopeia (USP) for the determination of cefalexin impurity in cefradine in terms of the greater stability of the chromatogram baselines and the higher precision, i.e., the lower % relative standard deviation (RSD). Based on the comparison of the two HPLC methods, the cefadroxil method was recommended to replace the TLC method, which has been prescribed by the EP as the official method for determination of extraneous impurities in cefradine.

• 정보통신설비학회논문지
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• 제3권1호
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• pp.88-101
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• 2004

The Third Generation (3G) cellular mobile communication systems aim at providing higher data rates, improved quality of service, support for multimedia applications and global roaming. Cdma2000 and Universal Mobile Telecommunication System (UMTS) have emerged as two leading 3G standards in USA and European countries, respectively. Both the standards are capable of delivering high bandwidth data, voice and multimedia services to users of mobile equipment, but are not directly interoperableand are not available across different geographic areas, due to which global roaming is not possible in true sense of using single mobile equipment. However, both UMTS and cdma2000 are based on wideband code division multiple access (WCDMA) as the access method. Due to this, there exist some inherent commonalities between them. In this paper we will try to exploit the commonalities between the two standards in order to design an ASIC, which can provide dual standard capability. This paper discusses the physical layer aspects of the two standards and proposes an approach to design an ASIC which can be mapped to baseband processing part of the physical layer and is capable of delivering for either of the two aforementioned standards.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제26권4호
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• pp.296-309
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• 2022

Timer options are one of the contingent claims that, for given the variance budget, its payoff depends on a random maturity in terms of the realized variance unlike the standard European vanilla option with a fixed time maturity. Since it was first launched by Société Générale Corporate and Investment Banking in 2007, the valuation of the timer options under several stochastic environment for the volatility has been conducted by many researches. In this study, we propose the pricing of timer power options combined with standard timer options and the index of the power to the underlying asset for the investors to actualize lower risks and higher returns at the same time under the uncertain markets. By using the asymptotic analysis, we obtain the first-order approximation of timer power options. Moreover, we demonstrate that our solution has been derived accurately by comparing it with the solution from the Monte-Carlo method. Finally, we analyze the impact of the stochastic volatility with regards to various parameters on the timer power options numerically.

• 대한의용생체공학회:의공학회지
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• 제43권4호
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• pp.199-213
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• 2022

EN ISO 14971:2012 a risk management standard approved and applied as a European standard in 2012, will be adopted and applied as ISO 14971:2019 published in December 2019, ISO/TR 24971(Guidance) published in June 2020 from May 2022. After that, it is applied to IVDD surveillance and IVDR new and conversion, and the manufacturer is already preparing for application or is starting preparation for application. In addition, 98/78/EEC IVDD applied from 1998 will also be applied as REGULATION (EU) 2017/746 IVDR from May 2022. In particular, in IVDR, the requirements for post-marketing investigations such as Post Market Surveillance (PMS), Summary of safety and performance(SSP), Periodic Safety Update Report(PSUR) and Post Market Performance Follow Up(PMPF), which were not required in the existing IVDD, increased, and the contents were also specified. This study focused on ISO14971:2019 among these strengthened and newly applied regulations, and tried to present a detailed analysis and application plan of Post Market Surveillance (PMS) required by 2017/746 IVDR.

• Structural Engineering and Mechanics
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• 제87권4호
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• pp.347-361
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• 2023

This research aims to assess the behavior of reinforced concrete (RC) residential buildings when moment-resisting frames (MRFs) are used as the lateral resisting system. This investigation was conducted using MIDAS Gen v.19.0. Buildings with various plan footprints (Square, Rectangular, Circular, Triangular, and Plus-Shaped), and different heights (15 m, 30 m, 45 m, and 60 m) are investigated. The defined load cases, the equivalent static lateral load pattern, and the response spectrum function were defined as stated by the American Standard (ASCE 7-16), the 1997 Uniform Building Code (UBC97), the Egyptian Code for Loads (ECP-201), and the European Standard (EC8). Extensive comparisons of the results obtained by the different codes (including the story displacement, the story drift, and the base shear) were undertaken; to assess the response of moment-resisting multi-story framed buildings under lateral loads. The results revealed that, for all study cases under consideration, both ECP-201 and EC8 gave smaller base shear, displacement, and drift by one third to one fourth, around one fourth, around one fifth, respectively for both the ELF and RSA methods if compared to ASCE 7-16 and UBC97.