• Clinical and Experimental Pediatrics
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• 제51권9호
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• pp.1007-1011
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• 2008

목 적 : 열성 경련은 소아에서 가장 흔한 경련의 원인으로 우리나라의 경우 6-9%의 발생율을 보인다. 열성 경련의 원인으로 유전적인 소인이 중요한 것으로 생각되고 있지만 아직까지 열성경련과 관련된 정확한 유전자는 밝혀지지 않았다. $IL-1{\beta}$은 내인성 발열인자로서 열성 경련의 발병에 중요한 역할을 할 것으로 생각된다. 방 법 : 40명의 열성경련 환아(가족형 20명, 산발형 20명)와 33명의 대조군을 대상으로 하여 말초혈액에서 DNA를 추출했으며 PCR을 통해 분석하였다. $IL-1{\beta}$ gene의 -31, -511 promoter region에서 C/T biallelic polymorphism의 빈도를 대조군과 단순 열성경련 군(가족형과 산발형)으로 나누어 각각 비교해 보았다. 결 과 : 두 군간 다형성의 빈도는 통계학적으로 유의한 차이를 보이지 않았다. 결 론 : 통계학적 의의는 없으나 가족력이 있는 열성경련 군에서 CT/CT의 빈도가 상대적으로 높게(70.0%) 측정되어 많은 수의 환아를 대상으로 한 연구가 필요할 것으로 보인다.

• 한국경영과학회지
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• 제34권1호
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• pp.29-37
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• 2009

This paper proposes a curtailed-sequential probability ratio test (SPRT) control chart. For using the conventional SPRT control chart, the number of items inspected in a sampling point should have no restriction since items in a sampling point are inspected one by one until an SPRT Is terminated. The number of observations taken in a sampling point, however, has an upper bound since sampling and testing of an item is time-consuming or expensive. When the sample size reaches the upper bound without evidence of an in-control or out-of-control state of a process, the proposed chart makes a decision using the sample mean of all observations taken in a sampling point. The properties of the Proposed chart are obtained by a Markov chain approach and the performance of the chart is compared with fixed sample size (FSS) and variable sample size (VSS) control charts. A comparative study shows that the proposed chart performs better than VSS control charts as well as conventional FSS control charts.

• 한국정보통신학회논문지
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• 제5권1호
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• pp.34-40
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• 2001

WRC-2000에서 지상망과 정지궤도(GSO)를 이용한 위성통신 및 방송으로 분배된 Ku(14/11GHz) 및 Ka(30/20GHz)대역의 일부를 비정지궤도(non-GSO) 위성시스템과 공유하여 사용키로 결정함에 따라, 비정지궤도 위성시스템과 기존 정지궤도 위성망간 주파수대역의 공유문제, 간섭기준 및 간섭영향 평가 등에 관한 연구의 필요성이 제기되어 본 논문에서는 우리나라 위성망의 등가전력속밀도를 계산하기 위해 네 가지 분석방법을 사용하였다.

• 한국통신학회논문지
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• 제18권8호
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• pp.1146-1158
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• 1993

In this paper, parallel scrambling techniques are considered for practical use in the SDH transmission and the ATM transmission. In the ATM transmission, there are two ways of transmitting ATM cells - the SDH-based and the cell-based - and the corresponding scrambling techniques differ accordingly. For the SDH transmission and the SDH-based ATM transmission, the FSS (frame synchronous scrambling) is applied to the STM frames : while for the cell-based ATM trans-mission, the DSS(distributed sample scrambling) is used on the ATM cell stream. The parallel scrambling techniques are examined for the FSS and the DSS, and applied to achieve the parallel FSSs for use in the SDH and the SDH-based ATM transmission along with the parallel DSS applicable to the cell-based ATM transmission. The resulting(8, 4) PSRG(parallel shift resister generator) and (8, 16) PSRG based parallel scramblings are directly applicable for the STM-1 rate processing of the STM-4 and STM-16 scramblings, respectively. Likewise, the resulting (1, 8)PSRG and double-sampling-double-correction based parallel scrambling techniques can be practically used for a low-rate processing of the SDH-based and the cell-based ATM signal scrambling respectively.

• Journal of the Korean Data and Information Science Society
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• 제12권1호
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• pp.89-97
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• 2001

Chen and Chen(FSS, 1993, 159-168) presented a reasonable analytical model of fuzzy closed-loop systems and proposed a method to analyze the stability of fuzzy control by the relational matrix of fuzzy system. Chen, Lu and Chen(IEEE Trans. Syst. Man Cybern., 1995, 881-888) formulated the sufficient and necessary conditions on stability of fuzzy closed-loop control systems. Gang and Chen(FSS, 1996, 27-34) deduced a linguistic relation model of a fuzzy closed loop control system from the linguistic models of the fuzzy controller and the controlled process and discussed the linguistic stability of fuzzy closed loop system by a linguistic relation matrix. In this paper, we study more on their models. Indeed, we prove the existence and uniqueness of equilibrium state $X_e$ in which fuzzy system is stable and give closed form of $X_e$. The same examples in Chen and Chen and Gang and Chen are treated to analyze the stability of fuzzy control systems.

• 한국벤처창업학회:학술대회논문집
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• 한국벤처창업학회 2006년도 추계학술발표회
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• pp.275-299
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• 2006

This study aims at examining the early-stage financing scale for entrepreneur to build small & medium business. The data was collected from the DART (Data Analysis, Retrieval and Transfer System) of Korean Financial Supervisory Service(FSS) in the main. The results of this study show that small & medium business needs equipment & operation financing for about 37 months extent to reach Break-Even Point. The limitations of this study are data collections from registered firms on Korean FSS primarily and no showing about the early stage financing scale for building small & Medium Business concretely. Small & Medium business entrepreneur have to make a early stage finance plan according to a necessary equipment and operating cost in their business field for 37 months extent.

• Journal of electromagnetic engineering and science
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• 제9권1호
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• pp.46-52
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• 2009

This paper conducts a study on the frequency-dependent filtering and blocking effects of a variety of periodic structures, dubbed frequency selective surface(FSS). The periodic structures of interest are 1D and 2D repeated patterns of metal patches or slots sitting on the interface between the two different regions in the layered media which will show the capacitive or inductive behaviors and incorporated with the electromagnetic bandgap(EBG) geometry as another stratified media. Besides the normal substances so called double positive(DPS)-type in the layered media, metamaterials of double negative(DNG) are considered as layering components on the purpose of investigating the unusual electromagnetic phenomena. Frequency responses of transmission(absorption in terms of scattering) and reflection will be calculated by a numerical analysis which can be validated by the comparison with the open literature and demonstrated for the periodic structures embedding metamaterials or not. Most importantly, numerous examples of FSS will present the useful guidelines to have absorption or reflection properties in the frequency domain.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2002년도 추계학술대회 및 정기총회
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• pp.1-4
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• 2002

There have been several tipical methods being used to measure the fuzziness (entropy) of fuzzy sets. Pedrycz is the original motivation of this paper. This paper studies the entropy variation on the fuzzy numbers with arithmetic operations(addition, subtraction, multiplication) and the relationship between entropy and information energy. It is shown that through the arithmetic operations, the entropy of the resultant fuzzy number has the arithmetic relation with the entropy of each original fuzzy number. Moreover, the information energy variation on the fuzzy numbers is also discussed. The results generalize earlier results of Pedrycz [FSS 64(1994) 21-30] and Wang and Chiu [FSS 103(1999) 443-455].

• 한국군사과학기술학회지
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• 제18권4호
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• pp.369-375
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• 2015

In this paper, transparent circuit analog radar absorbing structure with angular stability for stealth aircraft canopy was proposed and designed. To obtain wideband electromagnetic absorption, optical transparency and smaller thickness, we proposed the novel FSS(Frequency Selective Surface) for X-band and implemented the resistive FSS and PEC(Perfect Electric Conductor) plane using ITO(Indium Thin Oxide) coating with optical transmissivity of 90 %. Reflection loss characteristics for different incident angles of both TE(Transverse Electric) and TM(Transverse Magnetic) polarizations are presented through simulations. We then fabricated the proposed structure to verify the simulation results. The comparisons between the simulation and measured results show good agreements. The results also show that the proposed radar absorbing structure can provide better frequency stability for different incidence angles and polarizations as well as optical transparency. We can apply this proposed structure to the canopy of stealth aircraft and other stealth applications for visible transparency.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 G
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• pp.2876-2878
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• 1999

There have been several tipical methods being used to measure the fuzziness (entropy) of fuzzy sets. Pedrycz is the original motivation of this paper. This paper studies the entropy variation on the fuzzy numbers with arithmetic operations(addition, subtraction, multiplication). It is shown that through the arithmetic operations, the entropy of the resultant fuzzy number has the arithmetic relation with the entropy of each original fuzzy number. This paper generalize earlier results of Pedrycz [FSS 64(1994) 21-30] and Wang and Chiu [FSS 103(1999) 443-455].