• Title/Summary/Keyword: forward selection method

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Problems and Countermeasures of Control Group Design in Randomized Controlled Trials of Herbal Medicine (한약제제 무작위 대조군 연구에서 대조군 설계의 문제점과 대안)

  • Yun, Young-Hee;Choi, In-Hwa
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.21 no.2
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    • pp.94-101
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    • 2008
  • Objectives : To discuss the types of control groups in randomized controlled trials (RCTs) of herbal medicine, and to provide suggestions for improving the design of control group in future clinical trials. Methods : We reviewed the 8 articles about clinical trial design of Chinese herbal preparation which were published from 2005 through 2008. We selected those articles from CNKI(中國知識基礎施設工程(http://www.cnki.net)). Results : It is necessary to have control group in randomized controlled trials(RCTs) of Korean herbal preparation. But there are problems in the selection of appropriate control group drug. This paper lists several problems about the choice of control drug and puts forward some proposals and countermeasures. There are problems such as ethics and manufacturing matching placebo and positive control herbal drug. Conclusion : To improve the quality of control group design, we introduce standard drug plus placebo drug method and add-on research for placebo control group design, double dummy technique, using negative control drug or composite control drug for active control group design.

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Factors Influencing the Effectiveness of Materials Handling Equipments Supplied in Agriculture

  • Park, Sung-Ha
    • Journal of the Ergonomics Society of Korea
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    • v.30 no.4
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    • pp.503-507
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    • 2011
  • Objective: This paper presents the factors influencing the effectiveness of materials handling equipments in agriculture. Background: Agriculture is one of the job categories where work-related musculoskeletal disorders(MSDs) are the most common. Statistics shows that majority of farm workers is exposed to repetitive and forceful body movements, lifting, lowering, pushing, pulling, or carrying heavy materials. In such a working environment, materials handling equipments are required and introduced to assist in the prevention of MSDs and other farm injuries. Method: Examples of materials handling equipments are rail carts, portable lifts, and bale handlers. Contributing factors influencing the effectiveness of materials handling equipments supplied in agriculture were identified based on the lessons learned from previous government-funded ergonomic projects. Results: Contributing factors identified include: (1) forward-looking attitude for the standardization of farming, its environments, and handling equipments, (2) participation of farm members in the process and evaluation of project, (3) leadership of project manager, (4) reinforcement of safety education and training, and (5) project selection and priority of handling equipment. Conclusion: Government-funded research planners, farmers, ergonomists, and farm machine experts are recommended to consider the factors identified when implementing materials handling equipments in agriculture. Application: Actual or potential application of this research includes recommendation for the effective implementation of material materials handling equipments in agricultural sectors.

A Method of Avoid flooding in the Cluster (클러스터 내의 플러딩 회피 방안)

  • Kim, Tae-Wook;Sang, Nguyen Quang;Tuan, Van Phu;Kong, Hyung-Yun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.05a
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    • pp.677-680
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    • 2015
  • In this paper, we propsed scheme to mitigate conflict and loss of message in vehicle communication. And vehicles that exist in the moving direction, were grouping to the cluster form. Through, to select best relay vehicle, transmit a message to the destination. In addition, we applied the double rayleigh fading environment so that can applied in real-environments. Therefore, vehicle communication network applied proposed scheme, can be problem of mitigate conflict and loss of message. Thus, Increase the reliability of the received signal.

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Software for adaptable eccentric analysis of confined concrete circular columns

  • Rasheed, Hayder A.;El-Fattah, Ahmed M. Abd;Esmaeily, Asad;Jones, John P.;Hurst, Kenneth F.
    • Computers and Concrete
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    • v.10 no.4
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    • pp.331-347
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    • 2012
  • This paper describes the varying material model, the analysis method and the software development for reinforced concrete circular columns confined by spiral or hoop transverse steel reinforcement and subjected to eccentric loading. The widely used Mander model of concentric loading is adapted here to eccentric loading by developing an auto-adjustable stress-strain curve based on the eccentricity of the axial load or the size of the compression zone to generate more accurate interaction diagrams. The prediction of the ultimate unconfined capacity is straight forward. On the other hand, the prediction of the actual ultimate capacity of confined concrete columns requires specialized nonlinear analysis. This nonlinear procedure is programmed using C-Sharp to build efficient software that can be used for design, analysis, extreme event evaluation and forensic engineering. The software is equipped with an elegant graphics interface that assimilates input data, detail drawings, capacity diagrams and demand point mapping in a single sheet. Options for preliminary design, section and reinforcement selection are seamlessly integrated as well. Improvements to KDOT Bridge Design Manual using this software with reference to AASHTO LRFD are made.

FARS: A Fairness-aware Routing Strategy for Mobile Opportunistic Networks

  • Ma, Huahong;Wu, Honghai;Zheng, Guoqiang;Ji, Baofeng;Li, Jishun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.5
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    • pp.1992-2008
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    • 2018
  • Mobile opportunistic network is a kind of ad hoc networks, which implements the multi-hop routing communication with the help of contact opportunity brought about by the mobility of the nodes. It always uses opportunistic data transmission mode based on store-carry-forward to solve intermittent connect problem of link. Although many routing schemes have been proposed, most of them adopt the greedy transmission mode to pursue a higher delivery efficient, which result in unfairness extremely among nodes. While, this issue has not been paid enough attention up to now. In this paper, we analyzed the main factors that reflect fairness among nodes, modeled routing selection as a multiple attribute decision making problem, and proposed our Fairness-aware Routing Strategy, named FARS. To evaluate the performance of our FARS, extensive simulations and analysis have been done based on a real-life dataset and a synthetic dataset, respectively. The results show that, compared with other existing protocols, our FARS can greatly improve the fairness of the nodes when ensuring the overall delivery performance of the network.

QSPR analysis for predicting heat of sublimation of organic compounds (유기화합물의 승화열 예측을 위한 QSPR분석)

  • Park, Yu Sun;Lee, Jong Hyuk;Park, Han Woong;Lee, Sung Kwang
    • Analytical Science and Technology
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    • v.28 no.3
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    • pp.187-195
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    • 2015
  • The heat of sublimation (HOS) is an essential parameter used to resolve environmental problems in the transfer of organic contaminants to the atmosphere and to assess the risk of toxic chemicals. The experimental measurement of the heat of sublimation is time-consuming, expensive, and complicated. In this study, quantitative structural property relationships (QSPR) were used to develop a simple and predictive model for measuring the heat of sublimation of organic compounds. The population-based forward selection method was applied to select an informative subset of descriptors of learning algorithms, such as by using multiple linear regression (MLR) and the support vector machine (SVM) method. Each individual model and consensus model was evaluated by internal validation using the bootstrap method and y-randomization. The predictions of the performance of the external test set were improved by considering their applicability to the domain. Based on the results of the MLR model, we showed that the heat of sublimation was related to dispersion, H-bond, electrostatic forces, and the dipole-dipole interaction between inter-molecules.

A Case Study on the VE/LCC for selection on Improvement of Soft Soil Ground (연약지반처리공법 선정을 위한 VE/LCC 사례 분석)

  • Kim, Yong-Deuk;Lee, Young-Dae;Acharya, Nirmal Kumar
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • 2006.11a
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    • pp.271-273
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    • 2006
  • Because effect of value elevation is great as it is fast that construction VE is enforcement, VE at the design phase is more and more important more than construction process phase. But, is exerting negative impact for construction process phase by various problem that happen at design phase, and is causing discord to between project partners. Therefore, quality security in design phase is important first of all. Hereupon, this study emphasized that need VE at the design phase of extension plan forward more and more because achieved process that derive conceptional estimation by quantitative value calculating value index (V) through provision of design function point (F) and LCC expense (C) by comparison method of construction and chooses optimum method of construction through VE/LCC analysis example in improvement of soft soil ground method choice process of design phase.

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Impossible Differential Cryptanalysis on ESF Algorithm with Simplified MILP Model

  • Wu, Xiaonian;Yan, Jiaxu;Li, Lingchen;Zhang, Runlian;Yuan, Pinghai;Wang, Yujue
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.10
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    • pp.3815-3833
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    • 2021
  • MILP-based automatic search is the most common method in analyzing the security of cryptographic algorithms. However, this method brings many issues such as low efficiency due to the large size of the model, and the difficulty in finding the contradiction of the impossible differential distinguisher. To analyze the security of ESF algorithm, this paper introduces a simplified MILP-based search model of the differential distinguisher by reducing constrains of XOR and S-box operations, and variables by combining cyclic shift with its adjacent operations. Also, a new method to find contradictions of the impossible differential distinguisher is proposed by introducing temporary variables, which can avoid wrong and miss selection of contradictions. Based on a 9-round impossible differential distinguisher, 15-round attack of ESF can be achieved by extending forward and backward 3-round in single-key setting. Compared with existing results, the exact lower bound of differential active S-boxes in single-key setting for 10-round ESF are improved. Also, 2108 9-round impossible differential distinguishers in single-key setting and 14 12-round impossible differential distinguishers in related-key setting are obtained. Especially, the round of the discovered impossible differential distinguisher in related-key setting is the highest, and compared with the previous results, this attack achieves the highest round number in single-key setting.

Applied Method of Energy Harvesting for Multi-Relay Environment (다중 중계기 환경에 대한 에너지 하베스팅의 적용 방안)

  • Kim, Tae-Wook;Kong, Hyung-Yun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.6
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    • pp.69-74
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    • 2014
  • In this paper, an energy harvesting scheme is investigated in the multi-relay cooperation communication. Our proposal is to maximize the diversity gain and overcome the disadvantages of the limited power wireless devices. The best relay is selected based on the maximizing channel gains from source to relays so that the harvested energy at selected relay is best. If an internal power of the best relay is lower than a defined target power, the best relay will harvest the energy from the source, and the help of the source-destination link is changed to the second best relay. By this operation method, the diversity gain is maintained and the performance of the network is improved. Finally, performance of the proposed protocol is analyzed in terms of bit error rate, utilization efficiency, power collection efficiency.

A Study on the Efficient Feature Vector Extraction for Music Information Retrieval System (음악 정보검색 시스템을 위한 효율적인 특징 벡터 추출에 관한 연구)

  • 윤원중;이강규;박규식
    • The Journal of the Acoustical Society of Korea
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    • v.23 no.7
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    • pp.532-539
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    • 2004
  • In this Paper, we propose a content-based music information retrieval (MIR) system base on the query-by-example (QBE) method. The proposed system is implemented to retrieve queried music from a dataset where 60 music samples were collected for each of the four genres in Classical, Hiphop. Jazz. and Reck. resulting in 240 music files in database. From each query music signal, the system extracts 60 dimensional feature vectors including spectral centroid. rolloff. flux base on STFT and also the LPC. MFCC and Beat information. and retrieves queried music from a trained database set using Euclidean distance measure. In order to choose optimum features from the 60 dimension feature vectors, SFS method is applied to draw 10 dimension optimum features and these are used for the Proposed system. From the experimental result. we can verify the superior performance of the proposed system that provides success rate of 84% in Hit Rate and 0.63 in MRR which means near 10% improvements over the previous methods. Additional experiments regarding system Performance to random query Patterns (or portions) and query lengths have been investigated and a serious instability problem of system Performance is Pointed out.