• 제목/요약/키워드: I/I analysis

검색결과 21,570건 처리시간 0.046초

결점나무 분석에서 실험적 방법을 이용한 불확실성 중요도 측도의 평가 (Evaluation of Uncertainty Importance Measure by Experimental Method in Fault Tree Analysis)

  • 조재균
    • 한국산업정보학회논문지
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    • 제14권5호
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    • pp.187-195
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    • 2009
  • 결점나무 분석에서 불확실설 중요도 측도는 basic event 확률 ($q_i$)의 불확실성이 top event 확률 (Q)의 불확실성에 얼마나 많이 기여하는지를 나타내는 측도로서, top event 확률의 불확실성을 감소시키기 위하여 어떤 basic event 확률의 불확실성을 감소시키는 것이 효과적인지를 밝히는데 사용된다. $q_i$의 분산 $\upsilon_i$가 백분율 단위로 한 단위 변화될 때 Q의 분산 V의 변화량을 평가하는 측도가 불확실성 중요도 측도로서 많은 저자들에 의해 제안되었으며, 이 측도를 계산하기 위해서는 V와 ${\partial}V/{\partial}{\upsilon}_i$를 해석적인 방법이나 몬테칼로 시뮬레이션을 사용하여 계산해야 한다. 그러나 대규모 결점나무에 대해서 V와 ${\partial}V/{\partial}{\upsilon}_i$를 해석적인 방법으로 계산하는 것은 매우 복잡하며, 몬테칼로 시뮬레이션을 사용하여 V와 ${\partial}V/{\partial}{\upsilon}_i$의 안정적인 추정치를 얻는 것은 매우 어렵다. 본 연구에서는 불확실성 중요도 측도를 실험적인 방법을 이용하여 평가하기 위한 방법을 제안한다. 제안된 방법은 몬테칼로 시뮬레이션을 이용하는 방법에 비해 계산량이 매우 적으며, 불확실성 중요도의 안정적 인 추정치를 제공한다.

전파 항법시스템을 위한 안테나 방향별 군지연 분석 (Analysis of the Directional Group Delay of the Antenna for the Radio Navigation System)

  • 정성훈;설동민;이철수;선중규
    • 한국항행학회논문지
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    • 제23권5호
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    • pp.386-391
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    • 2019
  • 본 논문은 정밀한 전파항법시스템 구현을 위해 안테나의 방향별 군지연 차이가 시스템에 미치는 영향을 분석하였다. 분석은 안테나 시뮬레이션과 시험을 통해서 수행 하였고, 시험은 무반향 챔버에서 진행 하였다. 안테나의 방향별 군지연은 위상(phase)을 기반으로 분석 하였으며, 측정 분석 결과 안테나의 방향별로 최대 약 7.7 ns까지 군지연 차이가 발생했다. 분석된 군지연 차이를 거리로 환산하면 약 2.31 m이며, 이를 실제 TOA (time of arrival)기반의 전파항법시스템에서 시험 하였다. 시험 결과 2.1 m의 거리 변화를 확인 하였으며, 이는 시뮬레이션과 챔버 시험 분석 값과 유사한 수치이다.

Genetic Engineering for Detection of Endocrine Disruption using I-18 C Gene Expression in Chironomus riparius

  • Kwak Inn-Sil
    • 환경생물
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    • 제23권3호
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    • pp.269-274
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    • 2005
  • The 2D/E gel analysis for polypeptide expression reflecting I-18 C gene (early-ecdysterone inducible gene) has conducted the emerged C. riparius adults from larval phase exposure to tebufenozide acting as an ecdysteroidal molting hormone. Control group, the amount of ORE II of the I-18 C gene was larger than that of ORE I of this gene. After treatments, ORE I of the I-18 C gene was overexpressed as the polypeptide, whereas ORF II of this gene was expressed as the polypeptide and was clearly reduced expression. Accordingly, we consider that tebufenozide exhibited endocrine disruptions related processing of ecdysteroid receptor protein reflecting ORF II of I-18 C gene. Also, earlier emergence day was related overexpressed polypeptide reflecting ORE I of I-18 C gene. In this study result, tebufenozide induced changing of physiological condition, and then polypeptide expression reflecting early-ecdysterone inducible I-18 C gene was different between control group and exposure group.

토러스 다중컴퓨터를 위한 입출력 자원의 배치와 성능 분석 (Placement and Performance Analysis of I/O Resources for Torus Multicomputer)

  • 안중석
    • 한국시뮬레이션학회논문지
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    • 제6권2호
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    • pp.89-104
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    • 1997
  • Performance bottleneck of parallel computer systems has mostly been I/O devices because of disparity between processor speed and I/O speed. Therefore I/O node placement strategy is required such that it can minimize the number of I/O nodes, I/O access time and I/O traffic in an interconnection network. In this paper, we propose an optimal distance-k embedding algorithm, and analyze its effect on system performance when this algorithm is applied to n x n torus architecture. We prove this algorithm is an efficient I/O node placement using software simulation. I/O node placement using the proposed algorithm shows the highest performance among other I/O node placements in all cases. It is because locations of I/O nodes are uniformly distributed in the whole network, resulting in reduced traffic in the intE'rconnection network.

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I-Umlaut in Old English: A Weak Trigger Effect

  • Moon, An-Nah
    • 영어영문학
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    • 제57권6호
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    • pp.1043-1065
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    • 2011
  • This study investigates i-umlaut which occurred in the period of pre Old English (OE) in two aspects: what motivates i-umlaut in OE and how the phenomenon can be analyzed within the framework of OT. Unlike root-controlled vowel harmony, i-umlaut in OE is triggered by the suffixal i or j in the unstressed syllable whereby a stressed root vowel becomes fronted or raised. In this study, it is proposed that i-umlaut in OE is driven by the weak trigger i or j to improve its poor perception: I-umlaut improves the poor perceptibility of the weak trigger by extending its feature-either [-back] or [-low]-onto the vowel in the stressed syllable. This study provides an OT-theoretic analysis utilizing the licensing account to vowel harmony proposed by Walker (2004, 2005). The licensing constraints, IDENT-IO(F) and the locally conjoined constraints are proposed and their interaction correctly captures the pattern of i-umlaut in OE. Also, it is shown that the licensing account proposed in this paper is superior to the previous analyses as well as the nonlicensing approaches in that it can provide a perceptual motivation couched in i-umlaut in OE.

자동 계측 기법을 이용한 서울 주요 가로의 녹시율 분석 (The Study on Index of Greeness in Streets of Seoul by Using Automatic Measurement Techniques)

  • 남창진;방재성;장대희
    • KIEAE Journal
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    • 제12권2호
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    • pp.93-101
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    • 2012
  • In this study, we measured the Index of Greeness(I.O.G) and analyzed factors that affect in downtown street of Seoul. The aim of this article is to provide an ways of improving I.O.G, with an emphasis on accuracy of measurement. We utilized the autimatic measurment techniques proposed by Tonosaki to solve the problem of accuracy in measurement. The result is as follows : Firstly, the average I.O.G of Gwanghwamun Plaza is 15.76%, Jongno is 11.48% and Dasanro(from Yaksu station to Beotigogae station) is 6.36%. According to the comprehensive analysis in three reseach areas, it shows that I.O.G is intimately linked with planting method, species of trees and the presence of wall planting. Secondly, it was analyzed that grass and ground-cover planting promote I.O.G better than other method. The I.O.G of photo which contains grass is 45.47%. According to the comparative analysis between tree planting and multi-planting method, the presence of lower planting showed a difference about 8.77% of I.O.G.. From the persipective of I.O.G, tree planting with two lines is more effective than one. The difference of two ways is about 3.24%. Thirdly, it is an efficint way to use the wall planting or vertical planting in order to promote I.O.G.. In Dasanro, The I.O.G of photo which contains wall planting or vertical planting is 45.47% in contrast to the average of I.O.G. is 6.36%. Fourthly, the difference of I.O.G between broadleaf tree and needleleaf tree was larger than we thought. If look closely confined to this study, the I.O.G of street planted by Pine is 3.61% and Eastern Sycamore Family Bottonwood is 12.55%.

I/Q 오차 보정 회로를 갖는 2.5GHz Quadrature LC VCO 설계 (Design of a 2.5GHz Quadrature LC VCO with an I/Q Mismatch Compensator)

  • 변상진;심재훈
    • 대한전자공학회논문지SD
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    • 제48권2호
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    • pp.35-43
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    • 2011
  • 본 논문에서는 Quadrature LC VCO(Voltage controlled oscillator)의 I/Q 오차를 분석하고, 그 분석된 결과를 이용하여 I/Q 오차 보정 회로를 제안한다. 제안된 I/Q 오차 보정 회로는 높은 주파수 대역폭을 요구하는 위상 오차 검출기를 사용하는 대신에 낮은 주파수 대역폭으로도 동작이 가능한 진폭 오차 검출기를 사용한다. 제안된 I/Q 오차 보정 회로의 검증을 위하여 2.5GHz Quadrature LC VCO가 $0.18{\mu}m$ CMOS 공정으로 제작 및 측정되었다. 측정결과 제안된 진폭 오차 검출기를 사용해도 기존의 위상 오차 검출기는 사용하는 경우들과 유사한 I/Q 오차 보정 성능을 얻을 수 있음을 확인하였다. 본 I/Q 오차 보정 회로는 1.8V 전원 전압에서 0.4mA 전류를 소모하며, 차지하는 칩 면적은 $0.04mm^2$이다.

Adult Trauma Patients with Isolated Thoracolumbar Spinous and Transverse Process Fractures May be Managed Conservatively to Improve Emergency Department Throughput

  • Awad, Kyrillos;Spencer, Dean;Ramakrishnan, Divya;Pejinovska, Marija;Grigorian, Areg;Schubl, Sebastian;Nahmias, Jeffry
    • Journal of Trauma and Injury
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    • 제34권1호
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    • pp.31-38
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    • 2021
  • Purpose: Traumatic vertebral injuries have a prevalence of 4-5% at level I centers. Studies have demonstrated that isolated thoracolumbar transverse process fractures (iTPF) rarely require brace or surgical interventions. We hypothesized that similarly isolated thoracolumbar spinous process fractures (iSPF) would have less need for bracing and operative interventions than SPFs with associated vertebral body (VB) fractures (SPF+VB). We performed a similar analysis for iTPF compared to transverse process fractures associated with VB injury (TPF+VB). Methods: In this single-center, retrospective study from 2012 to 2016, patients were classified into iSPF, SPF+VB, iTPF, and TPF+VB groups. Data including the fracture pattern, neurologic deficits, and operative intervention were obtained. The primary outcome studied was the need for bracing and/or surgery. A statistical analysis was conducted. Results: Of 98 patients with spinous process fractures, 21 had iSPF and 77 had SPF+VB. No iSPF patients underwent surgery, whereas 24 (31.17%) SPF+VB patients did undergo surgery (p=0.012). In the iSPF group, three patients (15%) received braces only for comfort, whereas 37 (48.68%) of the SPF+VB group required bracing (p=0.058). Of 474 patients with transverse process fractures, 335 had iTPF and 139 had TPF+VB. No iTPF patients underwent surgery, whereas 28 (20.14%) TPF+VB patients did (p≤0.001). Of the iTPF patients, six (1.86%) were recommended to receive braces only for comfort, while 68 (50.75%) of the TPF+VB patients required bracing (p<0.001). Conclusions: No patients with iSPF or iTPF required surgical intervention, and bracing was recommended to patients in these groups for comfort only. It appears that these injures may be safely managed without interventions, calling into question the need for spine consultation.

Insertion/deletion (I/D) in the Angiotensin-converting Enzyme Gene and Breast Cancer Risk: Lack of Association in a Meta-analysis

  • Pei, Xin-Hong;Li, Hui-Xiang
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권11호
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    • pp.5633-5636
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    • 2012
  • Purpose: Breast cancer is an important cause of cancer-related death in women. Numerous studies have evaluated the association between the insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene and breast cancer risk. However, the specific association is still controversial rather than conclusive. Therefore, we performed a meta-analysis of related studies to address this controversy. Methods: PubMed, EMBASE, Google Scholar and the Chinese National Knowledge Infrastructure databases were systematically searched to identify relevant studies. A meta-analysis was performed to examine the association between the I/D polymorphism in the ACE gene and susceptibility to breast cancer. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. Results: 10 separate studies of 7 included articles with 10,888 subjects on the relation between the I/D polymorphism in the ACE gene and breast cancer were analyzed by meta-analysis, and our results showed no association between the I/D polymorphism in the ACE gene and breast cancer in total population and different populations. No publication bias was found in the present study. Conclusions: The ACE I/D polymorphism may not be associated with breast cancer risk. Further large and well-designed studies are needed to confirm this conclusion.

섬유금속적층판의 모드 I 접합 거동 예측을 위한 Levenberg-Marquardt 기법 기반의 역해석 기법에 관한 수치적 연구 (Numerical Study on Inverse Analysis Based on Levenberg-Marquardt Method to Predict Mode-I Adhesive Behavior of Fiber Metal Laminate)

  • 박으뜸;이영헌;김정;강범수;송우진
    • Composites Research
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    • 제31권5호
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    • pp.177-185
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    • 2018
  • 섬유금속적층판은 금속과 섬유 강화 복합소재를 함께 적층한 하이브리드 재료 중 하나다. 섬유금속적층판은 계면의 접착층이 파괴되는 층간분리 현상이 발생할 수 있기 때문에 계면의 접착층에 대한 한계응력과 에너지 해방률을 실험적으로 도출해야만 한다. 하지만, 온도에 따른 에너지 해방률을 실험적으로 도출하는 과정에서 측정 장비의 사용 온도에 대한 제약을 받는다. 따라서, 본 연구에서는 Levenberg-Marquardt 기법을 기반한 역해석 기법을 사용하여 접착층에 대한 모드 I 한계응력과 에너지 해방률에 대한 예측 가능성을 확인하는 것이 목표다. 먼저, 한계응력은 접착층의 인장강도와 같다고 가정하였으며, 에너지 해방률은 DCB 시험(double cantilever beam test)을 수행하여 정의하였다. 또한, 유한요소법 기반 모델을 적용하여 한계응력과 에너지 해방률을 수치해석적으로 예측할 수 있는 지 확인하였다. 그 후, Levenberg-Marquardt 기법을 유한요소법 기반 모델에 적용하여 모드 I 한계응력과 에너지 해방률을 수치해석적으로 예측하였다. 아울러, 본 연구에서 사용한 역해석 기법의 수렴성을 확보하기 위하여 두 가지 경우의 초기 매개변수에 대한 역해석을 추가적으로 수행하였다. 결과적으로, 본 연구에서 사용한 역해석 기법은 모드 I 한계응력과 에너지 해방률을 효과적으로 예측할 수 있음을 보였다.