• Title/Summary/Keyword: Multi strategies

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An analysis of the predisposition of learners of English focusing on motivation and learning strategies (동기와 전략으로 본 영어 학습자들의 성향 분석)

  • Lee, Il-Yeon
    • English Language & Literature Teaching
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    • v.8 no.2
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    • pp.151-176
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    • 2003
  • Motivation and learning strategies, some of the important factors affecting language learning, have mostly been studied with reference to their relationship in terms of proficiency. This study investigated motivation and learning strategies and their relationship in order to find the inward predisposition of learners. Data was collected from 200 university students in Taejon and Chungnam province, Korea language learning strategies were measured by the Strategy Inventory for Language Learning(SILL), and motivation by the Attitude / Motivation Test Battery(AMTB), with adaptations for Koreans. The detailed analysis of the data Indicated that Korean university students were more motivated to learn English for a practical goal than a formal one. They had a strong willingness to learn but showed 'the tendency of the new generation' of choosing the easiest and most convenient ways in studying English in terms of motivational intensity and strategy use. Findings imply that there have to be some changes and improvements in the deep-rooted classroom teaching methods. A systematic device is needed to induce students to be autonomous learners, providing them with a variety of activities suitable for their purposes and levels, as in opportunities of contacting native speakers, multi-media language labs, the Internet etc.

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Optimum Structural Design of Tankers Using Multi-objective Optimization Technique (다목적함수 최적화기법을 이용한 유조선의 최적구조설계)

  • 신상훈;장창두;송하철
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.15 no.4
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    • pp.591-598
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    • 2002
  • In the ship structural design, the material cost of hull weight and the overall cost of construction processes should be minimized considering safety and reliability. In the past, minimum weight design has been mainly focused on reducing material cost and increasing dead weight reflect the interests of a ship's owner. But, in the past experience, the minimum weight design has been inevitably lead to increasing the construction cost. Therefore, it is necessary that the designer of ship structure should consider both structural weight and construction cost. In this point of view, multi-objective optimization technique is proposed to design the ship structure in this study. According to the proposed algorithm, the results of optimization were compared to the structural design of actual VLCC(Very Large Crude Oil Carrier). Objective functions were weight cost and construction cost of VLCC, and ES(Evolution Strategies), one of the stochastic search methods, was used as an optimization solver. For the scantlings of members and the estimations of objectives, classification rule was adopted for the longitudinal members, and the direct calculation method, GSDM(Generalized Slope Deflection Method), lot the transverse members. To choose the most economical design point among the results of Pareto optimal set, RFR(Required Freight Rate) was evaluated for each Pareto point, and compared to actual ship.

Cancer Chemoprevention by Dietary Phytochemicals: Rationale and Mechanisms (Dietary Phytochemical을 이용한 화학적 암에방과 그 작용 기전)

  • Surh, Young-Joon;Lee, Jong-Min
    • Environmental Mutagens and Carcinogens
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    • v.18 no.1
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    • pp.1-8
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    • 1998
  • Chemoprevention refers to the use of non-toxic chemical agents to prevent the neoplastic development by inhibiting, delaying, or reversing a multi-stage carcinogenesis. The primary goal of chemoprevention research is to identify or produce effective agents and strategies for clinical trials for applications to normal or high risk human populations. A large number of compounds have been tested for their possible chemopreventive activities, and it is of interest to note that many of them are naturally occurring substances. Thus, a variety of plant and vegetable constituents, particularly those included in our daily diet, have been found to possess substantial protective properties against experimental carcinogenesis. These substances, collectively known as dietary phytochemicals, exert their chemopreventive effects by influencing specific step(s) of multi-stage carcinogenesis: some inhibit metabolic activation or enhance detoxification of carcinogens, others interfere with covalent interactions between ultimate eloctrophilic carcinogens and the target cell DNA and still others may exert anti-promoting or anti-progressing effects. Mechanism-based interventions by use of safe dietary phytochemicals may provide one of the most practical and promising cancer chemopreventive strategies.

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Performance Improvement Strategies on Minimum Distance Classification for Large-Set handwritten Character Recognition (대용량 필기 문자인식을 위한 최소거리 분류법의 성능 개선 전략)

  • Kim, Soo-Hyung
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.10
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    • pp.2600-2608
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    • 1998
  • This paper proposes an algorithm for off line recognition of handwritten characters, especially effective for large-set characters such as Korean and Chinese characters. The algorithm is based on a minimum distance dlassification method which is simple and easy to implement but suffers from low recognition performance. Two strategies have been developed to improve its performance; one is multi-stage pre-classification and the other is candicate reordering. Effectiveness of the algorithm has been proven by and experimet with the samples of 574 classes in a handwritten Korean character catabase named PE02, where 86.0% of recognition accuracy and 15 characters per second of processing speed have been obtained.

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An Evaluation on IR Sensor Based Demand Controlled Ventilation Strategies for Multi-zone in the Apartment House (IR(Infrared) 센서기반 제어방법에 따른 공동주택 멀티 존 환기시스템 평가 연구)

  • Hong, Sung-Min;Yoon, Dong-Won
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.24 no.2
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    • pp.174-182
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    • 2012
  • In previous research, most occupant said that they have not operated ventilation system installed in the house, because of increasing of energy consumption and unconcern of ventilation. Therefore, it is necessary to applied the sensor based demand controlled ventilation for the IAQ(Indoor Air Quality) and improvement of energy efficiency in ventilation strategy. The propose of this study is to present a application method of IR(Infrared) sensor for multi-zone DCV(Demand Controlled Ventilation) in the apartment house. It is possible that IR sensor could be used for DCV, because that could detect the occupant and action. IR sensor based DCV strategies are established to evaluate characteristic of application in the apartment house and simulated by Contam program. As a result, they have some week points though, if they would be applied DCV with optimum strategy, it would be useful to improve IAQ, to reduce energy consumption.

Life-cycle cost optimization of steel moment-frame structures: performance-based seismic design approach

  • Kaveh, A.;Kalateh-Ahani, M.;Fahimi-Farzam, M.
    • Earthquakes and Structures
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    • v.7 no.3
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    • pp.271-294
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    • 2014
  • In recent years, along with the advances made in performance-based design optimization, the need for fast calculation of response parameters in dynamic analysis procedures has become an important issue. The main problem in this field is the extremely high computational demand of time-history analyses which may convert the solution algorithm to illogical ones. Two simplifying strategies have shown to be very effective in tackling this problem; first, simplified nonlinear modeling investigating minimum level of structural modeling sophistication, second, wavelet analysis of earthquake records decreasing the number of acceleration points involved in time-history loading. In this paper, we try to develop an efficient framework, using both strategies, to solve the performance-based multi-objective optimal design problem considering the initial cost and the seismic damage cost of steel moment-frame structures. The non-dominated sorting genetic algorithm (NSGA-II) is employed as the optimization algorithm to search the Pareto optimal solutions. The constraints of the optimization problem are considered in accordance with Federal Emergency Management Agency (FEMA) recommended design specifications. The results from numerical application of the proposed framework demonstrate the capabilities of the framework in solving the present multi-objective optimization problem.

Teaching-learning-based strategy to retrofit neural computing toward pan evaporation analysis

  • Rana Muhammad Adnan Ikram;Imran Khan;Hossein Moayedi;Loke Kok Foong;Binh Nguyen Le
    • Smart Structures and Systems
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    • v.32 no.1
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    • pp.37-47
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    • 2023
  • Indirect determination of pan evaporation (PE) has been highly regarded, due to the advantages of intelligent models employed for this objective. This work pursues improving the reliability of a popular intelligent model, namely multi-layer perceptron (MLP) through surmounting its computational knots. Available climatic data of Fresno weather station (California, USA) is used for this study. In the first step, testing several most common trainers of the MLP revealed the superiority of the Levenberg-Marquardt (LM) algorithm. It, therefore, is considered as the classical training approach. Next, the optimum configurations of two metaheuristic algorithms, namely cuttlefish optimization algorithm (CFOA) and teaching-learning-based optimization (TLBO) are incorporated to optimally train the MLP. In these two models, the LM is replaced with metaheuristic strategies. Overall, the results demonstrated the high competency of the MLP (correlations above 0.997) in the presence of all three strategies. It was also observed that the TLBO enhances the learning and prediction accuracy of the classical MLP (by nearly 7.7% and 9.2%, respectively), while the CFOA performed weaker than LM. Moreover, a comparison between the efficiency of the used metaheuristic optimizers showed that the TLBO is a more time-effective technique for predicting the PE. Hence, it can serve as a promising approach for indirect PE analysis.

Current Status of Systemic Therapy in Hepatocellular Carcinoma (진행성 간세포암종의 전신치료제)

  • Lee, Han Ah;Seo, Yeon Seok
    • Journal of Digestive Cancer Research
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    • v.8 no.1
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    • pp.65-70
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    • 2020
  • Although being one of the major causes of malignancy related death globally, hepatocellular carcinoma (HCC) has not received much attention in respect of novel drug development. Fortunately, several new drugs were found to be effective and tolerable in patients with advanced HCC from a number of phase 3 studies during the recent several years. Novel multi-targeted kinase inhibitors and immune checkpoint inhibitors were approved for clinical use, and combination strategies to maximize the potent of drugs demonstrated promising antitumor activity and safety with high response rate and improved safety profile. The increased number of available agents for HCC will contribute to change of treatment strategies and prognosis of patients with advanced HCC. Still, there is a many critical questions remain unanswered. Currently ongoing trials and future studies will provide better understanding of tumor biology and optimized criteria for patient selection and combination therapies.

Finite Element Modeling of 2-stage Axially Deploying Beams Vibrating Under Gravity (중력에 의해 진동하는 2단 축방향 전개 보의 유한요소 모델링)

  • Yun, Won-Sang;Bae, Gyu-Hyun;Beom, Hee-Rak;Hong, Seong-Wook
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.21 no.2
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    • pp.202-207
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    • 2012
  • Multi-stage deploying beams are useful for transporting parts or products handling in production lines. However, such multi-stage beams are often exposed to unwanted vibration due to the presence of their flexibility and time-varying properties. This paper is concerned with dynamic modeling and analysis of 2-stage axially deploying beams under gravity by using the finite element method. A variable domain finite element method is employed to develop the dynamic model. A rigorous method to account for engagement of two-stage beams during the deploying procedure is introduced by breaking the entire domain into three variable domains. Several deploying strategies are tested to analyze the residual vibrations. Several examples are illustrated to investigate the self-induced damping and the effects of deploying strategy on the vibrations.

A Pragmatic Method on Multi-Weapon Lanchester's Law (다중 란체스터 모형에 대한 실용적 해법)

  • Baik, Seung-Won;Hong, Sung-Pil
    • Journal of the Korean Operations Research and Management Science Society
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    • v.38 no.4
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    • pp.1-9
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    • 2013
  • We propose a heuristic algorithm for war-game model that is appropriate for warfare in which the maneuver of the attacker is relatively certain. Our model is based on a multi-weapon extention of the Lanchester's square law. However, instead of dealing with the differential equations, we use a multi-period linear approximation which not only facilitates a solution method but also reflects discrete natures of warfare. Then our game model turns out to be a continuous game known to have an ${\varepsilon}$-Nash equilibrium for all ${\varepsilon}{\geq}0$. Therefore, our model approximates an optimal warfare strategies for both players as well as an efficient reinforcement of area defense system that guarantees a peaceful equilibrium. Finally, we report the performance of a practical best-response type heuristic for finding an ${\varepsilon}$-Nash equilibrium for a real-scale problem.