한국산업표준(KS)에 따른 로크웰 경도 시험기의 불확도 산정에 관한 연구

탁내형,방건웅 한국열처리공학회 2000 熱處理工學會誌 Vol.13 No.3

Recently, uncertainty of hardeness became a major concern for the people working on the laboratory evaluation and accreditation. It is required to indicate uncertainty of hardness tester on the report after calibration. In addition to this, uncertainty of certified hardness reference block is also required to indicate on the certification sheet. Method on the evaluation of uncertainty in hardness measurement is agreed only recently for Rockwell hardness C scale. In this paper, a preliminary calculation of uncertainty based on type B evaluation has been made for hardness testers which satisfies the requirements of Korean Standards. It was found that the tolerance limit of mean value specified in KS should be increased to be compatible with the calculated uncertainty.

INTERACTIONS OF STOCK MARKETS WITHIN THE GREATER CHINA ECONOMIC BLOC

Bahng, Seung-Wook,Shin, Seung-Myo 연세대학교 동서문제연구원 2004 Global economic review Vol.33 No.3

This paper investigates what types of mutual relationships exist among the stock markets of the Greater China economic bloc, which include stock markets in Hong Kong and Taiwan, as well as stock markets in Shanghai and Shenzhen. Using the unit root test, co-integration analysis, and vector error correction model (VECM), this paper analyzes interrelationships among daily stock indices for the period from the beginning of 1992 to the end of 2001. Test results indicate the existence of one co-integrating vector, implying that a long-run equilibrium relationship holds among the four stock indices. Variance decomposition of forecast errors provides evidence that the Shenzhen stock market is the market most heavily influenced by the unexpected variations of other markets in the Greater China economic bloc.

Hearing Thresholds for a Geriatric Population Composed of Korean Males and Females

Bahng, Junghwa,Lee, Junghak The Korean Audiological Society 2015 Journal of Audiology & Otology Vol.19 No.2

<P><B>Background and Objectives</B></P><P>The purpose of the present study was to provide the hearing threshold levels in the elderly Korean population, and to compare Korean data with that in the International Organization for Standardization (ISO) 7029 (2000).</P><P><B>Subjects and Methods</B></P><P>Data were collected from a total of 526 ears from 112 males and 151 females aged 60-84 years. All participants were screened otologically by the procedure given in ISO 8253-1 (2010).</P><P><B>Results</B></P><P>Results showed that the pure-tone average was gradually elevated with increasing age. The amount of hearing loss was greater in males than in females, and the high frequency hearing thresholds were worse than the low frequency hearing thresholds in males and females. The hearing threshold levels were higher at low frequencies in males and at all frequencies in females than the norms of ISO 7029 (2000).</P><P><B>Conclusions</B></P><P>Results from this study will be partly used for standardization of hearing thresholds as a function of age in Korea and for updating the ISO 7029.</P>

Modification of Surface Layer during High Temperature Annealing and its Effects on the SiC Diode Characteristics

Bahng, Wook,Cheong, Hui Jong,Kang, In Ho,Kim, Seong Jin,Kim, Sang Cheol,Joo, Sung Jae,Kim, Nam Kyun Trans Tech Publications, Ltd. 2007 Materials science forum Vol.556 No.-

<P>We have investigated the influence of surface modification on the electrical properties of SiC diodes. Schottky diodes (SBDs) as well as PiN diodes were fabricated on n-type SiC substrate with an epilayer, and electrically characterized before and after high temperature annealing, and after removing the surface modified layer, respectively. The devices annealed without graphite cap layer showed ohmic behavior. The surface layer was modified to a conductive layer possibly due to the preferred sublimation of Si species. In order to confirm the existence of modified surface conductive layer, diode was fabricated on the same substrate and electrically characterized after removing 30nm-thick damaged layer by ICP-RIE. The leakage current reduced dramatically, as much as 7 orders of magnitude. The PiN diodes fabricated on the damaged surface layer showed the reverse leakage current and the breakdown voltage of 50mA and 1250V, respectively. While those of the diode fabricated after removing the damaged surface layer were 200nA at the breakdown voltage of 2100V, respectively.</P>

MICOM-Compatible ±4 1/2 Digit Analog to Digital Converter for Digital Multimeter Applications

Bahng, Sam Yong,Lee, Seong Ho,Choi, Eung Ju,Baek, Seung Bum,Kim, Suk Ki 대한전자공학회 1991 ICVC : International Conference on VLSI and CAD Vol.2 No.1

This paper reports a dual slope analog-to-digital To achieve high accuracy and high resolution, the converter working with a microcontroller to perform gain of integrator amplifier has to be high enough, complete digital multi-meter(DMM) functions. Auto-zeroing and X10 switched capacitor functions can be performed simultaneously to reduce offset errors as well as to improve the resolution of the UMM.

Two Stage Damage Identification by Combination of Damage Indicator Method and Neural Networks

Bahng, Eun-Young 동양대학교 2000 동양대학교 논문집 Vol.6 No.1

본 논문은 토목구조물의 부재단위의 손상도 추정법에 관한 내용이다. 본 논문에서 제시되는 방법은 과도한 미지수로 인한 문제를 피하기 위하여 2단계로 이루어진다. 먼저 손상지수법을 이용한 손상부재 탐색절차와 신경망을 사용한 손상정도 추정절차로 단계화 되어있다. 모드자료의 불확실성은 신경망의 노이즈첨가 학습을 적용하여 최소화하였으며, 모드형상 자료의 불완전한 측정문제를 극복하기 위하여 부분구조법 개념을 도입하였다. 제시된 방법의 효율성을 보이기 위해 트러스 구조물에 대한 예제해석을 수행하여 2단계 방법이 손상정도를 추정하는데 정확도를 향상시킴을 확인하였다.

Ensemble and Single-Molecule Spectroscopic Study on Excitation Energy Transfer Processes in 1,3-Phenylene-Linked Perylenebisimide Oligomers

Bahng, Hee Won,Yoon, Min-Chul,Lee, Ji-Eun,Murase, Yuichi,Yoneda, Tomoki,Shinokubo, Hiroshi,Osuka, Atsuhiro,Kim, Dongho American Chemical Society 2012 The Journal of physical chemistry B Vol.116 No.4

<P>1,3-Phenylene-bridged perylenebisimide dimer (<B>PBI2</B>) and trimer (<B>PBI3</B>) were prepared along with monomer reference (<B>PBI1</B>) using perylene imide-anhydride <B>5</B> as a key precursor. 3,3-Dimethylbut-1-yl substituents were introduced at the 2,5-positions of perylenebisimide (PBI) to improve the solubilities of <B>PBI</B> oligomers. Actually, no serious aggregation of <B>PBI2</B> and <B>PBI3</B> was detected in their dilute CH<SUB>2</SUB>Cl<SUB>2</SUB> solutions. Under these conditions, intramolecular electronic interactions among PBI chromophores have been revealed by measuring the photophysical properties at their ensemble and single-molecule levels. The excitation energy transfer times of <B>PBI2</B> (0.16 ps) and <B>PBI3</B> (0.60 ps) were determined from the two different observables, anisotropy depolarization, and singlet–singlet annihilation, respectively, which are considered as the incoherent Förster-type energy hopping (EEH) times as compared with the EEH time constant (1.97 ps) calculated on the basis of the Förster mechanism. The relatively short EEH times compared to similar PBI oligomers can be attributed to 1,3-phenylene linker, which assures a short distance between the chromophores and, as a consequence, makes it hard to treat the PBI unit as a point dipole. The limitation of point-dipole approximation to describe the PBI oligomers and additional through-bond type interactions can be attributed as the causes of the discrepancies in excitation energy transfer times. Considering these photophysical properties, we can suggest that 1,3-phenylene-linked PBI oligomers have potentials as molecular photonic devices including the artificial light-harvesting system.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpcbfk/2012/jpcbfk.2012.116.issue-4/jp208855u/production/images/medium/jp-2011-08855u_0003.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp208855u'>ACS Electronic Supporting Info</A></P>

Molecular engineering and solvent dependence of excitation energy hopping in self-assembled porphyrin boxes

Bahng, Hee Won,Kim, Pyosang,Sung, Young Mo,Maeda, Chihiro,Osuka, Atsuhiro,Kim, Dongho The Royal Society of Chemistry 2012 Chemical communications Vol.48 No.35

<P>It has been demonstrated that the direction and magnitude of transition dipole moments, and hence rates in the excitation energy hopping in the self-assembled porphyrin boxes can be tuned by insertion of ethynyl groups as well as the dielectric constant of solvent.</P> <P>Graphic Abstract</P><P>Excitation energy hopping in self-assembled porphyrin boxes. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2cc30834g'> </P>

名詞に接續する「せいで」の意味と機能

( Bahng Yoon-hyung ) 한국일어일문학회 2019 日語日文學硏究 Vol.110 No.-

본 논문은 명사에 접속하는 “세이데(せいで)”의 의미와 기능에 대하여 분석, 고찰 한 것이다. “세이데(せいで)”가 기본적으로 “바람직하지 않은 결과”를 나타낸다는 점을 지적한 것은 종래에 연구사례가 많이 있으나, “바람직한 결과”를 나타내는 것 같은 예문이 있다는 지적은 종래의 연구에서 거의 보이지 않는다. 또한 “세이데(せいで)”가 단문에서 사용될 때와 복문에서 사용될 때는 다른 특징이 보이지만 이것을 구분하여 고찰한 연구는 이루어진 적이 없다. 따라서 본 논문에서는 우선 단문에서 사용되는 경우와 복문에서 사용되는 경우를 구분하고, “바람직하지 않은 결과”를 나타내는 경우와 “바람직한 결과”를 나타내는 경우로 세분하여 각각의 특징에 대하여 기술하는 것을 목표로 했다. 그 결과는 다음과 같이 정리할 수 있다. 첫째, “세이데(せいで)”가 단문에서 사용되는 경우는 기본적으로 “바람직하지 않은 결과”를 나타낸다. 그러나 “바람직한 결과”를 나타내는 예문도 10례가 확인되었다. 이와 같은 단문에서 사용되는 경우, 전접명사가 “바람직하지 않은 결과” 와 “바람직한 결과”의 양쪽에 중복되는 경우는 보이지 않았다. 둘째, “세이데(せいで)”가 복문에서 사용되는 경우는 다음과 같이 ①“바람직하지 않은 결과”+“바람직하지 않은 결과”, ②“바람직하지 않은 결과”+“바람직한 결과”, ③“바람직한 결과”+“바람직하지 않은 결과”, ④“바람직한 결과”+“바람직한 결과”를 나타내는 경우의 네 가지로 나눌 수 있다. 이중에서 ③과 ④의 경우에도 “오카게데(おかげで)”가 아니라 “세이데(せいで)”가 사용되는 것을 알 수 있었다. 한편, 단문과 복문의 양쪽에서 사용된 전접명사는 개별어수로 14개가 확인되었다. 이상의 내용을 종합하면 종래의 연구결과와는 다르게, 단문에서는 명사에 접속하는 “세이데(せいで)”는 “바람직하지 않은 결과”뿐만 아니라 “바람직한 결과”도 나타낼 수 있으며, 복문에서는 “세이데(せいで)”의 바로 뒤에도 “바람직한 결과”가 올 수 있다고 말할 수 있다. In this paper, the meanings and the functions of "seide" connected with nouns are examined and analyzed. A lot of previous research papers reported that “seide” commonly represents “undesirable results” in the sentences, but none of them showed that “seide” has the opposite meaning of “desirable results” in some example sentences. “Seide” has different characteristics when it is used in the simple sentence and used in the complex sentence. However, no previous literature has separately focused on two cases of sentences. In the paper the different cases of “seide” in the simple sentence and in the complex sentence are distinguished and analyzed. More detailed investigations are classified with the meanings of “undesirable results” and “desirable results”. The results can be summarized as follows. First, when "seide" is used in a simple sentence, it basically indicates the meaning of "undesirable result". However, ten example sentences exist and confirm that “seide” surprisingly has the opposite meaning of "desirable results". Second, when "seide" is used in a complex sentence, four cases can be considered as in the below: ①"undesirable result"+"undesirable result", ②"undesirable result"+"desirable result", ③"desirable result”+"undesirable result", and ④"desirable result”+"desirable result". Among them, ③ and ④ cases show that "seide" is used instead of "okagede". In conclusion, "seide" connected with nouns shows the meaning of “desirable results” in the special cases of the simple sentences although it represents “undesirable results” in most simple sentences. Similarly in several complex sentences, the predicates right after “seide” are somtimes used to have the meaning of “desirable results”.

Development of a low-energy beam transport system at KBSI heavy-ion accelerator

Bahng, Jungbae,Lee, Byoung-Seob,Sato, Yoichi,Ok, Jung-Woo,Park, Jin Yong,Yoon, Jang-Hee,Choi, Seyong,Won, Mi-Sook,Kim, Eun-San Elsevier 2015 Nuclear Instruments & Methods in Physics Research. Vol.769 No.-

<P><B>Abstract</B></P> <P>The Korea Basic Science Institute has developed a heavy ion accelerator for fast neutron radiography [1]. To meet the requirements for fast neutron generation, we have developed an accelerator system that consists of an electron cyclotron resonance ion source (ECR-IS), low-energy beam transport (LEBT) system, radio-frequency quadrupole (RFQ), medium-energy beam transport system, and drift tube linac. In this paper, we present the development of the LEBT system as a part of the heavy ion accelerator system, which operates from the ECR-IS to the RFQ entrance.</P>