• 한국농공학회논문집
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• 제61권4호
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• pp.11-22
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• 2019

The objective of this study was to improve the cross-sectional area and height estimation method using stream width. Stream water levels should be calculated together to simulate inundation of agricultural land. However, cross-sectional survey data of small rural rivers are insufficient. The previous study has developed regression equations between the width and the cross-sectional area and between the width and the height of stream cross-section, but can not be applied to a wide range of stream widths. In this study, cross-sectional survey data of 6 streams (Doowol, Chungmi, Jiseok, Gam, Wonpyeong, and Bokha stream) were collected and divided into upstream, midstream and downstream considering the locations of cross-sections. The regression equations were estimated using the complete data. $R^2$ between the stream width and cross-sectional area was 0.96, and $R^2$ between width and height was 0.81. The regression equations were also estimated using divided data for upstream, midstream and downstream considering the locations of cross-sections. The range of $R^2$ between the stream width and cross-sectional area was 0.86 - 0.91, and the range of $R^2$ between width and height was 0.79 ? 0.92. As a result of estimating the cross-sections of 6 rivers using the regression equations, the regression equations considering the locations of cross-sections showed better performance both in the cross-sectional area and height estimation than the regression equations estimated using the complete data. Hydrologic Engineering Center - River Analysis System (HEC-RAS) was used to simulate the flood stage analysis of the estimated and the measured cross-sections for 50-year, 100-year, and 200-year frequency floods. As a result of flood stage analysis, the regression equations considering the locations of cross-sections also showed better performance than the regression equations estimated using the complete data. Future research would be needed to consider the factors affecting the cross-sectional shape such as river slope and average flow velocity. This study can be useful for inundation simulation of agricultural land adjacent to an unmeasured stream.

• 항공우주시스템공학회지
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• 제18권1호
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• pp.21-28
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• 2024

본 논문에서는 회전익 블레이드의 단면 구조 정보를 통해 블레이드의 단면 강성을 예측하고, 재료 정보를 이용하여 단면 강성을 예측할 수 있는 심층 신경망 기반 네트워크 예측 모델의 설계 및 적절성 검토를 수행하였다. 재료 정보를 네트워크 입력으로 갖는 예측 모델의 경우, 블레이드 단면 부재 재료의 탄성 계수를 네트워크의 입력으로 고려하여 단면 강성을 예측하도록 설계하였다. 또한, 단면 구조 정보를 네트워크 입력으로 갖는 예측 모델의 경우, 블레이드의 단면을 구성하는 단면 부재의 위치와 두께 정보를 네트워크 입력으로 고려하여 단면 강성을 예측하도록 설계하였다. 각 예측 모델은 심층신경망 구조를 기반으로 설계하였으며, 단면 해석 프로그램인 KSAC2D를 통한 단면 해석 결과를 네트워크의 훈련 및 검증 데이터로 사용하였다.

• 제어로봇시스템학회논문지
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• 제11권9호
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• pp.768-773
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• 2005

A new approach for human foot modelling and last design based on the cross sectional method is presented in this paper. The proposed last design method utilizes the dynamic trimmed parametric patches for the foot 3D data and last 3D data. The cross section a surface of 3D foot for the 3D last, design modeling of free form geometric last shapes. The proposed last design scheme wraps the 3D last data surrounding the measured 3D foot data with the effect of deforming the last design rule The last design rule of the FFD is constructed on the FFD lattice based on foot-last shape analysis. In addition, the control points of FFD lattice are constructed with cross sectional data interpolation methods from the a finite set of 3D foot data. The deformed 3D last result obtained from the proposed FFD is saved as a 3D dxf foot data. The experimental results demonstrate that the last designed with the proposed scheme has good performance.

• 한국IT서비스학회지
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• 제12권4호
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• pp.91-108
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• 2013

In this study, we empirically examine cross-sectional determinants of IT personnel size of Korean listed companies from year 2004 to year 2009. Also, cross-sectional determinants of IT personnel size involved in managing internal control over financial reporting (hereafter, "ICFR") were examined. IT personnel or IT workers are recognized as critical intangible resources comprising firm's IT capability. Although IT personnel are regarded as important resources, there are not much information about factors explaining the size of firms' IT personnel. Fortunately, the Korean governmant regulates that every listed companies should dislclose the number of IT workers and ICFR-related IT personnel in their annual reports. This study utilizes the mandatorily disclosed IT personnel data to analyze cross-sectional determinants of korean listed companies' IT personnel size. Empirical results show that profitability, uncertainty, leverage, industry types are statistically significant factors associated with the size of IT personnel.

• Composites Research
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• 제30권6호
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• pp.343-349
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• 2017

A multifield variational formulation is developed for the finite element (FE) cross-sectional analysis of composite beams. The cross-sectional warping displacements and sectional stresses are considered to be the primary variables through the application of Reissner's partially mixed principle. The warping displacements are modeled using generic FE shape functions with nonlinear distribution over the beam section. A generalized Timoshenko level stiffness matrix is derived which incorporates the effects of elastic couplings, transverse shear, and Poisson's deformations. The accuracy of the present analysis is validated for the stiffness constants and elastostatic responses of composite box beams which correlate well with the experimental data and other state-of-the-art approaches.

• 대한간호학회지
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• 제45권1호
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• pp.129-138
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• 2015

Purpose: The purpose of this study was to report the instrument modification and validation processes to make existing health belief model scales culturally appropriate for Korean Americans (KAs) regarding colorectal cancer (CRC) screening utilization. Methods: Instrument translation, individual interviews using cognitive interviewing, and expert reviews were conducted during the instrument modification phase, and a pilot test and a cross-sectional survey were conducted during the instrument validation phase. Data analyses of the cross-sectional survey included internal consistency and construct validity using exploratory and confirmatory factor analysis. Results: The main issues identified during the instrument modification phase were (a) cultural and linguistic translation issues and (b) newly developed items reflecting Korean cultural barriers. Cross-sectional survey analyses during the instrument validation phase revealed that all scales demonstrate good internal consistency reliability (Cronbach's alpha=.72~.88). Exploratory factor analysis showed that susceptibility and severity loaded on the same factor, which may indicate a threat variable. Items with low factor loadings in the confirmatory factor analysis may relate to (a) lack of knowledge about fecal occult blood testing and (b) multiple dimensions of the subscales. Conclusion: Methodological, sequential processes of instrument modification and validation, including translation, individual interviews, expert reviews, pilot testing and a cross-sectional survey, were provided in this study. The findings indicate that existing instruments need to be examined for CRC screening research involving KAs.

• 제어로봇시스템학회논문지
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• 제12권2호
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• pp.113-118
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• 2006

A new last design approach based on the Limb line FFD (LFFD) and Scale factor FFD (SFFD) is presented in this paper. The proposed last design method utilizes the dynamic trimmed parametric patches for the measured foot 3D data and last 3D data. Furthermore, the proposed last data generation system utilizes cross sectional data extracted obtained from the measured 3D foot data. First, the last design rule of the LFFD is constructed on the FFD lattice based on foot last shape analysis. Secondly, SFFD is constructed on the LFFD new lattice based on scale factor deformation. The scale factor is constructed on the boundary edges of polygonized patch and the cross section last data boundary edge of the polygon object. Suppose the two boundary curves have been preprocessed so that they run in the same direction and they forms the SF(Scale Factor). In addition, the control points of FFD lattice are derived with cross. sectional data interpolation methods from a finite set of 3D foot data.

• Water Engineering Research
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• 제3권4호
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• pp.269-278
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• 2002

A cross sectional analysis for residential water demand was conducted to help understand and explain the spatial and temporal variations in per capita water use in the rapidly growing city of Riyadh, Saudi Arabia. The analysis was based on data previously collected from May 1983 to June 1984. 195 randomly selected households were distributed to three groups according to house condition, household income level, and social and cultural factors. The generated models using stepwise multiple regression indicated that plot size and number of males, females and children are the most significant independent variables. Although, coefficients of determination achieved for most of the developed models were low (0.2-0.5), the independent variables could still explain a part of the variations fur such a complex social and cultural structure.

• 한국조사연구학회지:조사연구
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• 제12권2호
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• pp.89-112
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• 2011

본 연구는 농가경제조사를 패널자료화한 결과와 패널화된 자료를 이용하여 실제로 자료를 분석하는 예를 제시하였다. 본고의 분석결과 예시는 농가경제조사와 같은 반복횡단면자료의 경우 사후적으로 패널화함으로써 다양한 동태분석이 가능함을 보여주고 있다. 또한 횡단면가중치의 존재를 감안하였을 때 종단면가중치 문제도 비교적 수월하게 해결할 수 있는 가능성이 있음을 알 수 있다. 본고의 경험을 바탕으로 할 때 최근 통계청에서 새롭게 패널조사를 실시하려는 계획을 수립, 집행하고 있는 바, 이와 더불어 통계청에서 기존에 실시하고 있는 유사한 구조의 반복횡단면조사의 경우에도 패널화 작업을 수행할 필요가 있다고 판단된다. 물론 이러한 패널화 작업의 이점은 실제로 패널조사로 진행되고 있는 사업체조사에서 더욱 명확하게 나타날 것으로 예상되며, 향후에는 사업체 횡단면자료의 패널화작업을 시도할 필요가 있다고 할 것이다.

• Communications for Statistical Applications and Methods
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• 제17권6호
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• pp.899-907
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• 2010

무응답 대체(non-response imputation) 방법에 관한 많은 이론과 방법이 제안되었으며 실제 자료 분석에 이용되고 있다. 흔히 횡단면 무응답 대체를 위하여 다중대체법(multiple imputation)이 사용되고 있으며 2차년도 이상의 패널자료에는 종시점회귀대체법(cross-wave regression imputation)이 사용되고 있다. 본 연구에서는 패널자료 분석을 위하여 종시점회귀대체법의 일반형태인 시계열 대체법과 횡단면 무응답 대체법을 결합한 시계열-횡단면 다중 대체법을 제안하였다. 노동부의 매월노동통계 자료를 이용하여 제안한 방법과 기존의 종시점회귀대체법을 비교하여 우수함을 보였다.