• Title/Summary/Keyword: Model Matching Method

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Analysis of the Empirical Effects of Contextual Matching Advertising for Online News

  • Oh, Hyo-Jung;Lee, Chang-Ki;Lee, Chung-Hee
    • ETRI Journal
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    • v.34 no.2
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    • pp.292-295
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    • 2012
  • Beyond the simple keyword matching methods in contextual advertising, we propose a rich contextual matching (CM) model adopting a classification method for topic targeting and a query expansion method for semantic ad matching. This letter reports on an investigation into the empirical effects of the CM model by comparing the click-through rates (CTRs) of two practical online news advertising systems. Based on the evaluation results from over 100 million impressions, we prove that the average CTR of our proposed model outperforms that of a traditional model.

An intelligent Speed Control System for Marine Diesel Engine (선박용 디젤기관의 지능적인 속도제어시스템)

  • 오세준
    • Journal of Advanced Marine Engineering and Technology
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    • v.22 no.3
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    • pp.320-327
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    • 1998
  • The purpose of this study is to design the intelligent speed control system for marine diesel engine by combining the Model Matching Method and the Nominal Model Tracking Method. Recently for the speed control of a diesel engine some methods using the advanced control techniques such as LQ control Fuzzy control or H$\infty$ control etc. have been reported. However most of speed controllers of a marine diesel engine developed are still using the PID control algorithm But the performance of a marine diesel engine depends highly on the parameter setting of the PID controllers. The authors proposed already a new method to tune efficiently the PID parameters by the Model Mathcing Method typically taking a marine diesel engine as a non-oscillatory second-order system. It was confirmed that the previously proposed method is superior to Ziegler & Nichols's method through simulations under the assumption that the parameters of a diesel engine are exactly known. But actually it is very difficult to find out the exact model of the diesel engine. Therefore when the model and the actual diesel engine are unmatched as an alternative to enhance the speed control characteristics this paper proposes a Model Refernce Adaptive Speed Control system of a diesel engine in which PID control system for the model of a diesel engine is adopted as the nominal model and a Fuzzy controller is adopted as the adaptive controller, And in the nominal model parameters of a diesel engine are adjusted using the Model Matching Method. it is confirmed that the proposed method gives better performance than the case of using only Model Matching Method through the analysis of the characteristics of indicial responses.

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Optimal algorithm of part-matching process using neural network (신경 회로망을 이용한 부품 조립 공정의 최적화 알고리즘)

  • 오제휘;차영엽
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.143-146
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    • 1996
  • In this paper, we propose a hopfield model for solving the part-matching which is the number of parts and positions are changed. The goal of this paper is to minimize part-connection in pairs and net total path of part-connection. Therefore, this kind of problem is referred to as a combinatorial optimization problem. First of all, we review the theoretical basis for hopfield model to optimization and present two method of part-matching; Traveling Salesman Problem (TSP) and Weighted Matching Problem (WMP). Finally, we show demonstration through computer simulation and analyzes the stability and feasibility of the generated solutions for the proposed connection methods.

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Development of a link extrapolation-based food web model adapted to Korean stream ecosystems

  • Minyoung Lee;Yongeun Kim;Kijong Cho
    • Korean Journal of Environmental Biology
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    • v.42 no.2
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    • pp.207-218
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    • 2024
  • Food webs have received global attention as next-generation biomonitoring tools; however, it remains challenging because revealing trophic links between species is costly and laborious. Although a link-extrapolation method utilizing published trophic link data can address this difficulty, it has limitations when applied to construct food webs in domestic streams due to the lack of information on endemic species in global literature. Therefore, this study aimed to develop a link extrapolation-based food web model adapted to Korean stream ecosystems. We considered taxonomic similarity of predation and dominance of generalists in aquatic ecosystems, designing taxonomically higher-level matching methods: family matching for all fish (Family), endemic fish (Family-E), endemic fish playing the role of consumers (Family-EC), and resources (Family-ER). By adding the commonly used genus matching method (Genus) to these four matching methods, a total of five matching methods were used to construct 103 domestic food webs. Predictive power of both individual links and food web indices were evaluated by comparing constructed food webs with corresponding empirical food webs. Results showed that, in both evaluations, proposed methods tended to perform better than Genus in a data-poor environment. In particular, Family-E and Family-EC were the most effective matching methods. Our model addressed domestic data scarcity problems when using a link-extrapolation method. It offers opportunities to understand stream ecosystem food webs and may provide novel insights into biomonitoring.

Efficient Vibration Simulation Using Model Order Reduction (모델차수축소법을 이용한 효율적인 진동해석)

  • Han Jeong-Sam
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.3 s.246
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    • pp.310-317
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    • 2006
  • Currently most practical vibration and structural problems in automotive suspensions require the use of the finite element method to obtain their structural responses. When the finite element model has a very large number of degrees of freedom the harmonic and dynamic analyses are computationally too expensive to repeat within a feasible design process time. To alleviate the computational difficulty, this paper presents a moment-matching based model order reduction (MOR) which reduces the number of degrees of freedom of the original finite element model and speeds up the necessary simulations with the reduced-size models. The moment-matching model reduction via the Arnoldi process is performed directly to ANSYS finite element models by software mor4ansys. Among automotive suspension components, a knuckle is taken as an example to demonstrate the advantages of this approach for vibration simulation. The frequency and transient dynamic responses by the MOR are compared with those by the mode superposition method.

Case-Based Reasoning Cost Estimation Model Using Two-Step Retrieval Method

  • Lee, Hyun-Soo;Seong, Ki-Hoon;Park, Moon-Seo;Ji, Sae-Hyun;Kim, Soo-Young
    • Land and Housing Review
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    • v.1 no.1
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    • pp.1-7
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    • 2010
  • Case-based reasoning (CBR) method can make estimators understand the estimation process more clearly. Thus, CBR is widely used as a methodology for cost estimation. In CBR, the quality of case retrieval affects the relevance of retrieved cases and hence the overall quality of the reminding capability of CBR system. Thus, it is essential to retrieve relevant past cases for establishing a robust CBR system. Case retrieval needs the following tasks to obtain appropriate case(s); indexing, search, and matching (Aamodt and Plaza 1994). However, the previous CBR researches mostly deal with matching process that has limits such as accuracy and efficiency of case retrieval. In order to address this issue, this research presents a CBR cost model for building projects that has two-step retrieval process: decision tree and nearest neighbor methods. Specifically, the proposed cost model has indexing, search and matching modules. Features in the model are divided into shape-based and scale-based attributes. Based on these, decision tree is established for facilitating the search task and nearest neighbor method was utilized for matching task. In regard to applying nearest neighbor method, attribute weights are assigned using GA optimization and similarity is calculated using the principle of distance measuring. Thereafter, the proposed CBR cost model is developed using 174 cases and validated using 12 test cases.

Speed Control of a Diesel Engine by Means of the Model Matching Method (모델 맷칭법에 의한 디젤기관의 속도제어)

  • 유희환;하주식
    • Journal of Advanced Marine Engineering and Technology
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    • v.20 no.3
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    • pp.131-137
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    • 1996
  • The existing digital governors are in the beginning stage. Placing the focus on the marine site, most of the digital governors developed are still using the simple PID algorithm. But, the performance of a diesel engine is widely changed according to the parameters of the PID controller. So, this article describes a new method to adjust the parameters of the PID controller in a marine digital governor. In this paper, the diesel engine is considered as a nonoscillatory second order system. A new method to adjust the parameters of the PID controller for speed control of a diesel engine is proposed by means of the model matching method. Also, the simulations by numerical methods are carried out in cases of the exact understanding or out of the parameters of a diesel engine respectively. And this paper confirms that the proposed new method here is superior to Ziegler & Nichols's method through the comparisons and analysis of the characteristics of indicial responses.

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A Study on the Improvement of the Response Characteristic of the Electro-Hydraulic Rear Wheel Steering Gear (전자 유압식 후륜 조향 장치의 응답 특성 개선에 관한 연구)

  • 오인호;양경욱;이일영
    • Transactions of the Korean Society of Automotive Engineers
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    • v.5 no.6
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    • pp.192-201
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    • 1997
  • The feedback control scheme of the pressure control system of the rear wheel steering gear which has relatively large volume and sprung load was built up in order to improve th response characteristic of the system. The control algorithm chosen was a feedback compensator joined by a feedfoward compensator and the model matching method was used in the process of control system design. The structures and properties of the reference models were inspected and the parameters of the controller were decided. The improvement of the response characteristic of the pressure control valve by means of the feedback control is affirmed. Particularly, when the order of the system model is higher than the 2nd order, the effectiveness of the feedback control on the improvement of the response characteristic of the valve is distinct. And the convenience of the model matching method is the process of control system design is confirmed as well.

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Structural Dynamics Modification using Reduced Model for Having Non-matching Nodes (불일치 절점을 가지는 경우의 축약된 모델을 이용한 동특성 변경법)

  • Kang, Ok-Hyun;Park, Youn-Sik;Park, Young-Jin
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.830-833
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    • 2005
  • SDM(Structural Dynamics Modification) is to improve dynamic characteristics of a structure, more specifically of a base structure, by adding or deleting auxiliary(modifying) structures. In this paper, I will focus on the optimal layout of the stiffeners which are attached to the plate to maximize 1st natural frequency. Recently, a new topology method was proposed by yamazaki. He uses growing and branching tree model. I modified the growing and branching tree model. The method is designated modified tree model. To expand the layout of stiffeners, I will consider non-matching problem. The problem is solved by using local lagrange multiplier without the mesh regeneration. Moreover The CMS(Component mode synthesis) method is employed to reduce the computing time of eigen reanalysis using reduced componet models.

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On-line Signature Verification Using Fusion Model Based on Segment Matching and HMM (구간 분할 및 HMM 기반 융합 모델에 의한 온라인 서명 검증)

  • Yang Dong Hwa;Lee Dae-Jong;Chun Myung-Geun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.1
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    • pp.12-17
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    • 2005
  • The segment matching method shows better performance than the global and points-based methods to compare reference signature with an input signature. However, the segment-to-segment matching method has the problem of decreasing recognition rate according to the variation of partitioning points. This paper proposes a fusion model based on the segment matching and HMM to construct a more reliable authentic system. First, a segment matching classifier is designed by conventional technique to calculate matching values lot dynamic information of signatures. And also, a novel HMM classifier is constructed by using the principal component analysis to calculate matching values for static information of signatures. Finally, SVM classifier is adopted to effectively combine two independent classifiers. From the various experiments, we find that the proposed method shows better performance than the conventional segment matching method.