• 소음진동
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• 제10권4호
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• pp.648-654
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• 2000

A procedure to determine the realizable optimal positions of rigid supports is suggested to get a maximum fundamental natural frequency. a measured frequency response function based substructure-coupling technique is used to model the supported structure. The optimization procedure carries out the eigenvalue sensitivity analysis with respect to the stiffness of supports. As a result of such stiffness optimization, the optimal rigid-support positions are shown to be determined by choosing the position of the largest stiffness. The optimally determined support conditions are verified to satisfy the eigenvalue limit theorem. To demonstrate the effectiveness of the proposed method, the optimal support positions of a plate model are investigated. Experimental results indicate that the proposed method can effectively find out the optimal support conditions of the structure just based on the measured frequency response functions without any use of numerical model of the structure.

• 한국산업융합학회 논문집
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• 제25권2_2호
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• pp.263-269
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• 2022

In this study, the optimal support position determination and stability determination of the wedge wire screen were performed for the production of the wedge wire filter screen with improved mesh screen. In order to manufacture a filter screen using a wedge wire, the support rod wedge wire is first installed according to the filtering capacity, and then spot welding is performed while rotating the profile wire. In the existing manufacturing method, it was manufactured using a 3m rod wedge wire and then cut according to dimensions, but it required the manufacture of a 6m cylindrical screen. Due to the increase in wedge wire length, it is difficult to manufacture stress concentration at sagging and fixed positions. In order to shorten the time of analysis, a single wedge wire was applied instead of a plurality of wedge wires. The reliability and validity of the interpretation were presented and the results were derived. After selecting the support point at the 2m position, structural analysis was performed on the entire filter screen to confirm stability.The purpose of this study is to identify the maximum deflection of the wire for the production of a 6m wedge wire screen and secure design basic data so that it can work safely through optimal support.

• Journal of Advanced Marine Engineering and Technology
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• 제28권7호
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• pp.1165-1171
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• 2004

The free vibration analyses of the isotropic and CFRP laminated composite rectangular plates with point supports at the fix edge is performed by FEM. We showed optimal position and mode shape of point supports that maximized fundamental natural frequency of the isotropic and CFRP laminated composite rectangular plates by each aspect ratio and the number of point supports.

• 한국정밀공학회지
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• 제17권4호
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• pp.173-180
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• 2000

In the process of grinding a long slender type workpiece, such as ballscrew, by the external cylindrical grinding machine, the cylindricity of the workpiece depends on the distance of rests, the stiffness of supports, the diameter and material of workpiece. Conventionally the process needs to be supported by one or more rests to prevent static deflection and vibration. In this paper, the optimal position of the rests was investigated in order to minimize the cylindricity due to the static deflection, by taking compliance of the workpiece and structure into account. In order to obtain the optimal position of rests, a new modeling that is considering the spring effect of all support elements was established. Since it is so complicated to obtain the optimal position analytically for various conditions due to discontinuity, a genetic algorithm u as utilized.

• 한국산학기술학회논문지
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• 제21권4호
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• pp.138-144
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• 2020

육군의 공병은 여러 장비를 이용하여 다양한 작전을 수행 중이며, 대표적인 군사작전 분야로는 포병 진지구축지원이 있다. 포병은 아군의 후방에서 화력으로 적의 중심을 타격하는 임무를 수행하며, 이때 사격 위치 노출 방지를 위해 한 진지에서 여러 차례 사격 후 진지를 반드시 이동해야 함에 따라 제한된 수의 장비를 효율적으로 운용하여 다수의 진지를 신속히 구축하는 것이 필요하다. 본 연구에서는 진지 구축시 제약조건을 반영하여, 공병장비-팀(작업)-진지간 최적할당이 가능한 수리모형과 휴리스틱 알고리즘을 제시하고 이에 대한 실험결과를 제시하고자 한다. 본 논문에서 제안한 최적화 수리모형은 작은 크기의 문제에서는 최적해를 도출하나, 실제 공병대대 및 여단 규모의 장비배치 문제에서는 최적해 도출에 장시간이 소요되는 한계가 존재함에 따라, 수리모형 기반의 휴리스틱 역시 제안하였다. 해당 휴리스틱은 1단계에서 수리 모형의 일부 변수의 정수제약 조건을 완화하고 할당에 대한 최적해를 구하고, 해당 해를 원 수리모형에 추가하여 최종 해를 구하는 형태로 설계하였다. 이러한 휴리스틱은 최적해의 도출은 보장하지는 못하나 문제의 크기가 커져도 빠른 시간에 해를 도출할 수 있었다.

• 산업경영시스템학회지
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• 제40권1호
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• pp.11-21
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• 2017

Artillery fire power due to effectiveness which is hard to predict well-planned and surprising attack can give a fear and shock to the personnel and is a very core weapon system and takes a critical role in wartime. Therefore in order to maximize operational effectiveness, Army required protecting artillery and takes a quick attack action through rapid construction of artillery's positions. The artillery use artillery's position to prevent exposure by moving to other position frequently. They have to move and construct at new artillery's positions quickly against exposing existed place by foe's recognition. These positions should be built by not manpower but engineering construction equipment. Because artillery positions have to protect human and artillery equipment well and build quickly. Military engineering battalion have lots of construction equipment which include excavator, loader, dozer, combat multi-purposed excavator, armored combat earthmover dump truck and so on. So they have to decide to optimal number of Team combining these equipments and determine construction sequence of artillery's position in operational plan. In this research, we propose to decide number of Team efficiently and allocate required construction's positions for each Team under constraints of limited equipments and time. To do so, we develop efficient heuristic method which can give near optimal solution and be applied to various situation including commander's intention, artillery position's priority or grouping etc. This heuristic can support quick and flexible construction plan of artillery positions not only for using various composition's equipment to organize Teams but also for changing quantity of positions.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2016년도 춘계학술대회
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• pp.285-286
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• 2016

해상교통관제센터에 의해 실시간으로 수집되는 선박의 항해 데이터를 바탕으로 선박 항적 패턴 인식을 수행하고 이를 바탕으로 항적 모델을 추출하여 사전에 선위를 예측하는 기법을 제안한다. 항적 데이터의 처리와 가공, 항적 모델링을 위하여 Support Vector Regression 알고리즘이 사용되었으며, 적정 파라미터 선정을 위하여 k-fold cross validation과 grid search가 사용되었다. 제안된 항적 데이터 모델링 기법을 통하여 사전에 선박의 선위를 예측하여 해상교통과제사의 의사결정을 지원하고자 한다.

• Communications for Statistical Applications and Methods
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• 제30권3호
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• pp.245-258
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• 2023

This study proposes a modification to the objective function of the support vector machine for the linearly non-separable case of a binary classifier y_i ∈ {-1, 1}. The modification takes into account the position of each data item x_i from its corresponding class centroid. The resulting optimization function involves the centroid mean vector, and the spread of data besides the support vectors, which should be minimized by the choice of hyper-plane β. Theoretical assumptions have been tested to derive an optimal separable hyperplane that yields the minimal misclassification rate. The proposed method has been evaluated using simulation studies and real-life COVID-19 patient outcome hospitalization data. Results show that the proposed method performs better than the classical linear SVM classifier as the sample size increases and is preferred in the presence of correlations among predictors as well as among extreme values.

• 재활복지공학회논문지
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• 제11권1호
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• pp.29-35
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• 2017

기존의 가정용 요양침대는 매트리스 지지판(mattress support platform) 하부에 설치된 복잡한 기구부로 인해 저상화 실현이 어려웠다. 본 논문에서는 등판과 다리판의 각도를 조절하면서도 저상화가 가능한 요양침대의 구동 메커니즘을 제안한다. 등판과 다리판의 메커니즘은 듀얼 모터(dual motor)를 적용하고, 최적화 기법으로 설계변수를 결정하였다. 승강 메커니즘은 풀리(pulley)구조를 적용하여 제한된 구동기의 가동범위를 최대 두 배까지 높일 수 있도록 설계하였다. 건강한 5명의 피험자($24.4{\pm}0.5$세)가 방바닥에서 240mm의 저상 프로토타입 요양침대와, 600mm의 일반적인 높이의 침대에 올라갈 때의 그 이동 거리를 측정하여 저상화 침대에 대한 유효성을 평가하였다. 그 결과 저상 요양침대를 사용할 때의 이동 거리는 기존 높이의 침대에 비해 평균 38% 작았다. 이것은 저상요양침대가 고령자의 신체적 부담을 줄여주며, 일반침대보다 일상생활 지원에 효과적이라는 것을 보여주었다.

• 통상정보연구
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• 제9권1호
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• pp.277-295
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• 2007

This paper presents the ODR phenomenon with a specific focus on regulatory problems. It argues that the current regulatory framework for online dispute resolution is, to a large extent, defective. Existing deficiencies result not only from a lack of comprehensive ODR law, but also from the weakness of the other modalities of regulation : norms and market. The current today's approach to regulating ODR has been unsuccessful, and it is time to re-examine that position. I would like to say that suggesting details of the optimal ODR regulatory framework is beyond the scope of this paper. From a broader perspective, the field of ODR seems to be not sufficiently regulated. Neither by law, nor by the restrains set by other norms or market. Given the current weakness of the modalities of regulation, online dispute resolution requires greater institutional and international support. It appears that adoption of internationally harmonized ODR law would not hamper the development of norms and market, but rather support their proper growth. As a result, the co-regulation approach recommended in this paper is different from both traditional state-oriented models of regulation and self-regulatory systems. Arguably, this co-regulation approach is the optimal model for regulation of online dispute resolution under current circumstances.