• 대한지리학회지
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• 제46권2호
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• pp.212-232
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• 2011

이 연구의 목적은 이지역 코호트 요인법에 의한 인구 추계 방법론을 정립하고, 그것을 부산광역시의 장래 인구 추계에 적용하는 것이다. 우선 시도와 같은 지역 인구의 추계에 있어 우리나라의 공식적인 방법인 순이동 코호트-요인법이 갖는 한계를 예증하였다. 대안으로 지역간 코호트-요인법 중 전체 지역을 두 지역으로 구분한 후 지역 간의 전입과 전출을 분리하여 추계하는 이지역 코호트-요인법을 정립하였다. 이를 바탕으로 부산광역시의 2005~2030년에 대한 인구 추계를 3가지 시나리오 하에서 실행하였다. 순이동 방식을 취한 인구 추계와 이지역 방식을 취한 인구 추계 간에는 상당한 차이가 나타났는데, 전출 초과 지역인 부산의 경우 순이동 방식에서 더 빠른 인구 감소가 나타났다. 이지역 방식에 의한 부산 및 전국추계의 인구 변화 추세를 검토한 결과 추계가 상당히 합리적으로 이루어짐을 확인할 수 있었다. 결론적으로 본 연구에서 제시된 이지역 코호트-요인법은 순이동 코호트-요인법에 비해 논리적으로 더 정연하면서도 실제 추계에 있어서도 높은 유용성을 보여 주었다.

• Journal of Welding and Joining
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• 제22권6호
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• pp.25-29
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• 2004

Some industrial steel structures are composed by components linked by several welding joints to constitute an assembly. The main interest of assembly simulation is to evaluate the global distortion of welded structure. The general method, thermo-elasto-plastic analysis, leads to excessive model size and computation time. In this study, a simplified method called "Local and Global approach" was developed to break down this limit and to provide a accurate solution for distortion. Local and global approach is composed of 3 steps; 1) Local simulation of each welding joint on a dedicated mesh (usually very fine due to high thermal gradients), taking into account for the non linearity of the material properties and the moving heat source. 2) Transfer to the global model of the effects of the welding joints by projection of the plastic strain tensors. 3) Elastic simulation to determine final distortions in global model. The welding deformation test for mock-up structure was performed to verify this approach. The predicted welding distortion by this approach had a good agreement with experiment results.

• 한국멀티미디어학회논문지
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• 제9권9호
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• pp.1131-1138
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• 2006

본 논문에서는 지하에 매설된 통신 관로를 레이저 투영 영상 분석에 의해 검사하는 새로운 기법을 제안한다. 레이저 다이오드, 발광 다이오드와 카메라로 구성된 장비가 관내에 직접 투입되며, 레이저 다이오드는 관벽에 투영 영상을 생성하고 발광 다이오드는 내부 조명 장치로 사용되며, 카메라는 관로 영상을 획득한다. 카메라에서 전달된 다양한 조건의 관로 영상에 대해 투영 영역을 정확히 분할하기 위하여, 새로운 객차 모델과 다중 임계치 기법을 이용한다. 분할된 투영 고리의 형상은 최소 직경과 푸리에 표기자에 의해 표현하여 관로의 상태를 규칙에 기반하여 분류한다. 국부적인 최소 직경과 전역적인 푸리에 표기자를 모두 사용하므로 파손된 관로, 찌그러진 관로 등의 다양한 조건에서 높은 분류 성능을 나타낼 수 있으며, 여러 상태의 영상에 대한 실험 결과는 2% 미만의 오분류로 높은 성능을 나타냈다.

• 농촌계획
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• 제26권2호
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• pp.13-24
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• 2020

This study analyzed the management efficiency of local food stores that are increasing recently. The analysis targeted 25 local food outlets in Jeonbuk area, and the analysis method analyzed the efficiency by CCR model. The input variables used to analyze the input-oriented efficiency of local food stores are business expenses, employees, organizational number of participating farms, and number of items, and sales are used as output variables. The main contents of the analysis are as follows. First, local food outlets increased due to support projects such as the government, local governments, and agricultural cooperatives, but their dependence was high. Second, the management efficiency of 25 local food stores in Jeonbuk is 28.0% when the efficiency is 1.000, and 72.0% of inefficient local food stores. Third, considering the projection point and the reference group, there was room for improvement in input variables. Therefore, it was determined that improvement efforts are needed to secure the continuity of local food outlets in the future. However, this study will require review of variable selection and analysis methods for further analysis.

• 한국농공학회지
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• 제39권1호
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• pp.112-121
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• 1997

The aim of this study was to analyze the slope stability relating to the failure of cut slopes and the characteristics of stress-strain relations obtained by limit equilibrium method, finite element method, and stereographic projection method for the reinforced cut slopes. The following conclusions were made : 1.To use stereographic projection method led to little possibility to take the toppling and wedge failure while to use the other methods led to the failure. It was recommended to reduce the slope inclination from 1:1 to 1: 1.5~1 :1.8 and adopt coir mesh method to protect the slope surface. position with the horizontal displacement after final excavation moved to the excavation base. The maximum shear strain values concentrated at the excavation base indicated the possibility to induce the local failure. 3. It was recommended that the slope inclination for blast rock with the slope height larger than l0m was 1: 0.5, 1:1, and 1: 1~1 :1.5 for hard rocks, soft and ordinary rocks, and ripping and soils, respectively. 4. Berm width criteria for blast rock with the slope height larger than l0m were recommended as follow : 2~3m per 20m slope height for hard rocks, 1 ~2m per l0m slope height for soft and ordinary rocks, 1 ~ l.5m per 5m slope height for ripping and soils.

• 한국산림과학회지
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• 제103권4호
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• pp.670-678
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• 2014

이 연구는 코호트 변화율법을 이용하여 우리나라 산촌지역 인구변동의 특성을 분석하고 장래 산촌인구를 추계한 것이다. 분석대상이 되는 산촌은 산림청에서 지정한 산촌진흥지역으로, 산림면적 비율 70% 이상, 인구밀도 111인/$km^2$, 경지면적 비율 21% 이하인 읍 면으로 정의한다. 산촌의 인구변동 특성을 살펴보면 지난 20년 간 산촌 인구는 급격히 감소하였고 노령화 지수는 상승하였다. 연령별로는 10~30대 젊은 층의 인구 유출이 많고 40대 이상 장년층의 유입이 증가하였다. 젊은 세대 인구가 감소하는 것은 교육과 취업을 위해 도시로 이동하는 경우가 많기 때문이며, 장년층 인구 증가는 귀농 귀촌에 대한 관심 증대의 영향으로 생각된다. 이러한 추세가 지속된다면 산촌인구는 2030년에 68만 명, 산촌의 노령화 지수는 1,035로 상승하여 국토의 균형 발전과 산림의 지속가능한 경영에 문제를 초래할 것이다. 따라서 산촌경제 활성화와 안정화를 위한 정책적 개입이 필요하다.

• Journal of Multimedia Information System
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• 제4권2호
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• pp.79-82
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• 2017

Smoke and fire have different shapes and colours. This article suggests a fully connected system which is used two features using Adaboost algorithm for constructing a strong classifier as linear combination. We calculate the local histogram feature by gradient and bin, local binary pattern value, and projection vectors for each cell. According to the histogram magnitude, this paper applied adapted weighting value to improve the recognition rate. To preserve the local region and shape feature which has edge intensity, this paper processed the normalization sequence. For the extracted features, this paper Adaboost algorithm which makes strong classification to classify the objects. Our smoke detection system based on the proposed approach leads to higher detection accuracy than other system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권11호
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• pp.4502-4518
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• 2015

Fisher linear discriminant analysis (LDA) is one of the most popular projection techniques for feature extraction and has been widely applied in face recognition. However, it cannot be used when encountering the single sample per person problem (SSPP) because the intra-class variations cannot be evaluated. In this paper, we propose a novel method called local similarity based linear discriminant analysis (LS_LDA) to solve this problem. Motivated by the "divide-conquer" strategy, we first divide the face into local blocks, and classify each local block, and then integrate all the classification results to make final decision. To make LDA feasible for SSPP problem, we further divide each block into overlapped patches and assume that these patches are from the same class. To improve the robustness of LS_LDA to outliers, we further propose local similarity based median discriminant analysis (LS_MDA), which uses class median vector to estimate the class population mean in LDA modeling. Experimental results on three popular databases show that our methods not only generalize well SSPP problem but also have strong robustness to expression, illumination, occlusion and time variation.

• Archives of Plastic Surgery
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• 제33권1호
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• pp.101-106
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• 2006

Nipple reconstruction is an important step in breast reconstruction after mastectomy. The authors' preferred reconstructive technique is the local C-V flap in case that a small opposite nipple is not adequate for composite graft. This flap produces an excellent reconstruction, but it is not easy to produce an adequate projection and firmness of the nipple. This article describes the technique and experience in nine patients treated over two years with dermis(scar tissue) graft for nipple reconstruction. This is the first report of application of autologous dermis(scar tissue) grafting to reconstruct a nipple primarily after breast mound reconstruction, decreasing the absorption of the reconstructed nipple and increasing the hardness. The dermis(scar tissue) is taken from scar revision and/or dog-ear correction in the second stage operation after free TRAM flap breast reconstruction. And the dermis(scar tissue) graft is inserted vertically between the local flaps and horizontally under the reconstructed nipple base. Between September 2002 and February 2005, nine patients underwent C-V flap with dermis(scar tissue) graft as a part of their nipple reconstruction. The patient's ages ranged from 28 to 55 years old (mean, 41.1 years old). The follow-up period ranged from 5 to 35 months, with an average of 14.5 months. None of the nipples showed skin flap necrosis or local infection, and uneventful wound healing. Our result showed good nipple projection with less absorption and enough firmness. Our experiences shows that dermis(scar tissue) grafts in C-V flap is a very useful method for nipple reconstruction.

• Journal of Positioning, Navigation, and Timing
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• 제3권1호
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• pp.25-30
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• 2014

Differential Global Positioning System-Correction Projection (DGPS-CP) algorithm, which has been suggested as a method of correcting pre-calculated position error by projecting range-domain correction to positional domain, is a method to improve the accuracy performance of a low price GPS receiver to 1 to 3 m, which is equivalent to that of DGPS, just by using a software program without changing the hardware. However, when DGPS-CP algorithm is actually realized, the error is not completely eliminated in a case where a reference station does not provide correction of some satellites among the visible satellites used in user positioning. In this study, the problem of decreased performance due to the difference in visible satellites between a user and a reference station was solved by applying the Multifunctional Transport Satellites (MTSAT) based Augmentation System (MASA) correction to DGPS-CP, instead of local DGPS correction, by using the Satellite Based Augmentation System (SBAS) operated in Japan. The experimental results showed that the accuracy was improved by 25 cm in the horizontal root mean square (RMS) and by 20 cm in the vertical RMS in comparison to that of the conventional DGPS-CP.