• 한국환경생태학회지
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• 제16권4호
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• pp.421-432
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• 2003

백두대간상의 정령치~복성이재 구간 능선부에 대해 34개 조사지(면적 500$m^2$)를 설정하여 식생구조를 파악하였다. TWINSPAN 및 DCA분석에 의해 조사지는 소나무-리기다소나무군락(I), 소나무군락(II), 소나무-일본잎갈나무군락(III), 신갈나무군락(IV)으로 분리되었다. 백두대간 정령치-복성이재 구간은 대부분 소나무가 우점하고 있었으며, 종다양성은 비산비야적인 특징으로 산악형 지역에 비해 낮게 나타났다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 D
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• pp.1976-1978
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• 2001

In this paper, a new robust deadbeat minimax FIR filter (DMFF) is proposed for continuous-time state space signal models. Linearity, deadbeat property, FIR structure, and independence of the initial state information will be required in advance, in addition to a performance index of the worst case gain between the disturbance and the current estimation error. The proposed DMFF is obtained by directly minimizing a performance index with the deadbeat constraint. The proposed DMFF is represented first in a standard FIR form and then in an iterative form. The DMFF will be shown to be used also for the IIR structure. It is shown that the DMFF is similar in form to the existing receding horizon unbiased FIR filter (RHUFF) with some noise covariances. The former is a deterministic filter, while the latter is a stochastic filter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 G
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• pp.2911-2913
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• 1999

This paper suggest an optimal identification method to complex and nonlinear system modeling that is based on Fuzzy-Neural Network(FNN). The FNN modeling implements parameter identification using HCM algorithm and optimal identification algorithm structure combined with two types of optimization theories for nonlinear systems, we use a HCM Clustering Algorithm to find initial parameters of membership function. The parameters such as parameters of membership functions, learning rates and momentum coefficients are adjusted using optimal identification algorithm. The proposed optimal identification algorithm is carried out using both a genetic algorithm and the improved complex method. Also, an aggregate objective function(performance index) with weighted value is proposed to achieve a sound balance between approximation and generalization abilities of the model. To evaluate the performance of the proposed model, we use the time series data for gas furnace, the data of sewage treatment process and traffic route choice process.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.972-975
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• 2004

In order to reduce the noise of BLDC motor, a systematic optimization procedure for rotor structure is presented. The noise index is defined as the sum of volume velocity of FE-model that are calculated at the dominant frequencies during dehydration process, which is based on the principle of radiation simple volume source. Then, the five design variables are selected to represent the shape and layout or rotor structure. This discrete design optimization problem for minimizing the noise index is solved by 3-level orthogonal array based effect analysis. Finally, the response surface method (RSM) combined optimization approach is employed for more refining the approximate optimum.

• 항공우주시스템공학회지
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• 제15권2호
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• pp.1-9
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• 2021

In this paper, a thickness compensation function is introduced to consider the shear deformation and warping effect resulting from increased thickness in the composite multi-cell wing box. The thickness compensation function is used to perform the structure optimization of the multi-cell. It is determined by minimizing the error of an analytical formula using solid mechanics and the Ritz method. It is used to define a structural performance prediction expression due to the increase in thickness. The parameter is defined by the number of spars and analyzed by the critical buckling load and the limited failure index as a response. Constraints in structural optimization are composed of displacements, torsional angles, the critical buckling load, and the failure index. The objective function is the mass, and its optimization is performed using a genetic algorithm.

• Earthquakes and Structures
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• 제20권3호
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• pp.261-278
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• 2021

In the current work, a series of seismic analyses of one-storey asymmetrical reinforced concrete (R/C) framed buildings is accomplished while the effect of soil deformability on the structural response is investigated. A comparison is performed between the simplified elastic behavior of R/C elements according to the structural regulations' instructions to the possible non-linear behavior of R/C elements under actual circumstances. The target of the time history analyses is the elucidation of the Soil-Structure Interaction (SSI) effect in the seismic behavior of common R/C structures by examining the possible elastic or elastoplastic behavior of R/C sections because of the redistribution of the internal forces by employing a realistic damage index. The conclusions acquired from the presented elastic and elastoplastic analyses supply practical guidelines towards the safer design of structures.

• Asian Journal of Innovation and Policy
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• 제12권3호
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• pp.323-344
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• 2023

This study investigates the resilient structural characteristics of a region by assessing the impact of the financial crisis. Utilizing panel data at the prefecture level for metropolitan cities across pre-shock (2006-2008), shock (2009), and post-shock (2010-2019) periods, we calculated an employment resilience index by combining the resistance and recovery indices. The panel logit regression measures the influences of the region's industrial structure and external economic factors in response to the global financial crisis. The results revealed that the diversity index of industries contributed to the post-shock recovery bounce-back. Additionally, the presence of large firms and industrial clusters within the region positively contributed to economic resilience. The specialization and the proportion of manufacturing industries showed negative effects, suggesting that regions overly reliant on manufacturing-centered specialization might be vulnerable to external shocks. Furthermore, excessive capital outflows for market expansion were found to have a detrimental impact on regional economic recovery.

• 한국환경생태학회지
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• 제33권5호
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• pp.587-595
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• 2019

도심 산지형 공원 내 식생유형별 요인이 공기이온에 미치는 영향력을 파악하고자 충주시 탄금대 공원을 대상으로 수행하였다. 측정지점은 능선부 내 수종, 흉고직경, 울폐도, 층위구조에 따라 설정하였으며, 기상요소와 공기이온을 측정하였다. 공기이온 측정결과, 양이온 발생량은 평균 $610.90{\pm}50.27ea/cm^3$, 음이온 발생량은 평균 $723.58{\pm}64.25ea/cm^3$, 이온지수는 $1.19{\pm}0.10$이였다. 식생유형에 따른 분석결과는 다음과 같다. 첫째, 공기이온은 수종, 흉고직경, 층위구조에 따라 차이가 발생하였으며, 통계적으로 유의한 것으로 분석되었다. 둘째, 이온지수와 식생유형과의 관계에서 수종, 흉고직경, 울폐도, 층위구조 모두에서 정의 상관관계로 분석되었으며, 양이온의 경우 수종, 흉고직경, 울폐도와 부의 상관관계, 음이온의 경우 수종, 흉고직경, 울폐도, 층위구조에서 정의 상관관계로 분석되었다. 셋째, 능선부 내 이온지수의 영향요인은 기상요인과 식생유형을 비교한 결과 식생유형의 상관계수가 더 높았으며, 세부적으로는 수종 > 층위구조 > 울폐도 > 흉고직경의 순이었다. 본 연구에서는 능선부를 대상으로 공기이온을 평가한 한계점이 존재한다. 이에 향후 공기이온에 대한 연구에서 지형구조, 식생유형을 모두 고려한 분석이 이루어져야할 것이며, 계절에 따른 변화 비교연구가 필요할 것으로 판단되었다.

• 정보관리학회지
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• 제33권3호
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• pp.155-176
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• 2016

본 연구는 한국학 연구 논문 텍스트의 의미 구조를 기반으로 하는 메타데이터를 적용한 학술정보시스템을 구축하여 기존 유사 시스템과의 비교를 통해, 텍스트 구조 기반 메타데이터의 활용 가능성을 확인해 보고자 하는 것을 목적으로 한다. 이를 위해 한국학술지인용색인(Korea Citation Index, KCI)에서 일정 기준을 충족하는 한국학 분야 연구 논문 데이터를 대상으로 의미 구조 메타데이터 항목을 적용한 시범적 검색 시스템(Korean Studies Metadata Database, KMD)을 구축하였으며, 동일한 검색 키워드를 적용하여 기존의 KCI 시스템과 비교했을 때 어떤 특징과 차이점을 갖는지 비교해 보았다. 연구 결과, KMD 시스템이 KCI에 비해 이용자의 검색 의도에 맞는 결과를 보다 효율적으로 보여주는 것으로 확인되었다. 즉 검색하고자 하는 키워드의 조합이나 조건식이 기존 시스템과 동일하더라도 검색 결과를 통해 최종적으로 연구 진행과 관련해 찾고자 하는 연구 목적, 연구의 대상 데이터나 시공간적 배경 등에 따른 검색 결과를 다양하게 보여줄 수 있는 것으로 나타났다.

• Journal of the Korean Wood Science and Technology
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• 제21권1호
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• pp.15-20
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• 1993

X-ray diffractograms of the vessel elements and the wood fibers of Quercus variabilis BLUME were recorded and resolved into characteristic reflections of cellulose I. Some differences were observed in the ratio of integrated intensity and crystallinity index between vessel elements and wood fibers. Present results suggest that cellulose crystal structure in the hardwood species was varied with the elements of wood.