• Title/Summary/Keyword: EM

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A Study on Floating Collar of Dragged Gears (인망그물의 부양깃판에 관하여)

  • 장지원
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.22 no.1
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    • pp.1-5
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    • 1986
  • In order to improve the net-mouth height of dragged gears, the authors devised models of floatingcollars of nylon cloth instead of floats and experimented with 4 types-A type (length 65em, breadth 3em), B type (length 65em, breadth 4em), C type (length 65em, breadth 5em) and D type (length 65 em, breadth 6em) attached respectively to the front edge of square of a model net after preliminary experimentation. These various types of floating collars were experimented in a circulating water channel to evaluate the characteristics of net-mouth height and hydrodynamic resistance and the effect of the length of bridles were also examined. The results obtained were as follows: 1. In case of attaching floats, the model net-mouth height reduced from 80 em to 20 em when current velocity was increased from 0.25m/see to 1m/sec. 2. In case of attaching floating collars, the model net-mouth heights were maintained 70 em, 71 em, 80 em, 78 em in maximum and 55 em, 63 em, 69 em, 73 em in minimum respectively even the current volocity was increased from 0.25 m/see to 1 m/see. 3. The model net-mouth height was reduced to 10 em maximum according to the current velocity and types of floating collars when the bridles were shortened 3~4 mm in length. 4. Hydrodynamic resistance of D type only was increased to 700 g in maximum and those of A, B, C type were reduced to 460 g in maximum at current velocity beyond 0.5 m/ see when bridles were shortened 3-4 mm in length. 5. But the model net-mouth heights became higher in accordance with breadth of floating coliars, B type was the best for this model net in case that hydrodynamic resistance was taken into account.

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Speedup of EM Algorithm by Binning Data for Normal Mixtures (혼합정규분포의 모수 추정에서 구간도수 EM 알고리즘의 실행 속도 개선)

  • Oh, Chang-Hyuck
    • Communications for Statistical Applications and Methods
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    • v.15 no.1
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    • pp.1-11
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    • 2008
  • For a large data set the high computational cost of estimating the parameters of normal mixtures with the conventional EM algorithm is crucially impedimental in applying the algorithm to the areas requiring high speed computation such as real-time speech recognition. Simulations show that the binned EM algorithm, being compared to the standard one, significantly reduces the cost of computation without loss in accuracy of the final estimates.

Accelerating the EM Algorithm through Selective Sampling for Naive Bayes Text Classifier (나이브베이즈 문서분류시스템을 위한 선택적샘플링 기반 EM 가속 알고리즘)

  • Chang Jae-Young;Kim Han-Joon
    • The KIPS Transactions:PartD
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    • v.13D no.3 s.106
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    • pp.369-376
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    • 2006
  • This paper presents a new method of significantly improving conventional Bayesian statistical text classifier by incorporating accelerated EM(Expectation Maximization) algorithm. EM algorithm experiences a slow convergence and performance degrade in its iterative process, especially when real online-textual documents do not follow EM's assumptions. In this study, we propose a new accelerated EM algorithm with uncertainty-based selective sampling, which is simple yet has a fast convergence speed and allow to estimate a more accurate classification model on Naive Bayesian text classifier. Experiments using the popular Reuters-21578 document collection showed that the proposed algorithm effectively improves classification accuracy.

Quality Improvement of Effective Microorganisms (EM) Pork Produced by Using EM (유용미생물(Effective Microorganisms; EM)로 사양한 EM Pork의 육질 개선 효과)

  • Han, Seung-Kwan
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.5
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    • pp.734-737
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    • 2005
  • This study was conducted to determine the effect of effective microorganism (EM) treatment in feeding system of swine on carcass characteristics. EM pork, which reared with EM additives and EM activated liquids, and conventional pork (non-EM pork) were stored at $4^{\circ}C$. Chemical composition and storage stability of EM pork were compared with conventional pork. Cholesterol content at EM pork was 71 mg/100 g, which is lower than that of conventional pork (83 mg/100 g) when the meats were stored at $4^{\circ}C$ refrigerator. And EM pork (0.165 MDA mg/kg) showed higher antioxidant effect than control pork (0.184 MDA mg/kg). And also protein denaturalization at EM pork showed lower rate $(3.19\;mg\%)$ than that of conventional pork $(4.9\;mg\%)$ when the meats were stored at $4^{\circ}C$ refrigerator, showing that inhibitory effect of protein denaturalization was increased up to $35\%$ over the conventional pork. These results show that the EM pork had superior traits in terms of cholesterol level, lipid oxidation and protein denaturalization to the conventional pork.

An Efficient Code Expansion from EM to SPARC Code (EM에서 SPARC 코드로 효율적인 코드 확장)

  • Oh, Se-Man;Yun, Young-Shick
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.10
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    • pp.2596-2604
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    • 1997
  • There are two kinds of backends in ACK:code generator(full-fledged backend) and code expander(fast backend). Code generators generate target code using string pattern matching and code expanders generate target code using macro expansion. ACK translates EM to SPARC code using code expander. The corresponding SPARC code sequences for a EM code are generated and then push-pop optimization is performed. But, there is the problem of maintaining hybrid stack. And code expander is not considered to passes parameters of a procedure call through register windows. The purpose of this paper is to improve SPARC code quality. We suggest a method of SPARC cod generation using EM tree. Our method is divided into two phases:EM tree building phase and code expansion phase. The EM tree building phase creates the EM tree and code expansion phase translates it into SPARC code. EM tree is designed to pass parameters of a procedure call through register windows. To remove hybrid stack, we extract an additional information from EM code. We improved many disadvantages that arise from code expander in ACK.

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Loop-loop EM inversion and its applicability to subsurface exploration

  • Sasaki, Yutaka
    • 한국지구물리탐사학회:학술대회논문집
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    • 2006.06a
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    • pp.3-6
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    • 2006
  • There are three types of frequency-domain loop-loop EM induction method, depending on the loop separation and their location relative to the ground surface: horizontal-loop EM (HLEM), fixed small-loop EM, and helicopter-borne EM (HEM) methods. Multidimensional inversion provides tomographic images of the subsurface resistivity structure and thus enhances the interpretational accuracy of loop-loop EM data. HLEM method is shown to be effective for exploring groundwater resources in weathered and fractured crystalline basement terrains in semi-arid regions. Also, HEM method is useful for locating weak zones in landslide areas. The applicability of inversion to small-loop EM data depends solely on the S/N ratio. The quadrature response of small-loop EM data can only give the equivalent conductivity of a homogenous half-space model, and thus the in-phase component is essential in inverting EM data. However, the in-phase response is much lower and decreases more rapidly with decreasing frequency than the quadrature response. Further work is needed to obtain conductivity-depth images from small-loop EM data.

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유용미생물(Effective Microorganisms ; EM)에 의한 돈육 보존의 효과

  • Han, Seung-Gwan
    • Proceedings of the Korean Society for Food Science of Animal Resources Conference
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    • 2004.05a
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    • pp.131-134
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    • 2004
  • EM이 돼지 사양에서 육질개선에 미치는 효과를 알아보기 위해 사양실험을 하였다. 일반적으로 사양한 돼지와 EM 축산사료첨가제와 EM 활성액을 정기적으로 급이하여 사양한 EM Pork를 도축한 후 각각의 돈육을 $4^{\circ}C$ 냉장온도와 $-18^{\circ}C$ 냉동온도에서 저장하였다. 그후 일반 돈육과 EM Pork의 일반성분 및 육질의 보존성에 관한 실험을 실시하였다. 단백질 변성에 관한 실험결과 일반 돈육을 5일간 냉동저장한 것은 3.72 mg%를 보였고 EM Pork는 3.2 mg%를 나타내 일반 돈육보다 15% 정도 단백질 변성을 지연시켰다. 또한, 일반 돈육을 5일간 냉장저장한 것은 4.9 mg%를 나타냈으나 EM Pork는 3.19 mg%를 나타내 일반 돈육보다 35% 단백질 변성 억제 효과를 보였다. 또한, 냉동 및 냉장 처리한 일반 돈육의 조단백질 함량은 각각 21.41%와 19.73%인데 비해 냉동 및 냉장 처리한 EM Pork는 각각 22.21%와 21.41%를 나타냈다. 이러한 결과는 단백질 변성과 관련된 것이라 볼 수 있다. 결론적으로 EM Pork육은 일반 돈육에 비해 단백질 변성 억제 효과가 15${\sim}$35% 정도 우수한 것으로 사료된다.

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A Novel Expectation-Maximization based Channel Estimation for OFDM Systems (Expectation-Maximization 기반의 새로운 OFDM 채널 추정 방식)

  • Kim, Nam-Kyeom;Sohn, In-Soo;Shin, Jae-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.4C
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    • pp.397-402
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    • 2009
  • Accurate estimation of time-selective fading channel is a difficult problem in OFDM(Orthogonal Frequency Division Multiplexing) system. There are many channel estimation algorithms that are very weak in noisy channel. For solving this problem, we use EM (Expectation-Maximization) algorithm for iterative optimization of the data. We propose an EM-LPC algorithm to estimate the time-selective fading. The proposed algorithm improves of the BER performance compared to EM based channel estimation algorithm and reduces the iteration number of the EM loop. We simulated the uncoded system. If coded system use the EM-LPC algorithm, the performance are enhanced because of the coding gain. The EM-LPC algorithm is able to apply to another communication system, not only OFDM systems. The image processing of the medical instruments that the demand of accurate estimation can also use the proposed algorithm.

Incremental EM algorithm with multiresolution kd-trees and cluster validation and its application to image segmentation (다중해상도 kd-트리와 클러스터 유효성을 이용한 점증적 EM 알고리즘과 이의 영상 분할에의 적용)

  • Lee, Kyoung-Mi
    • Journal of the Korean Institute of Intelligent Systems
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    • v.25 no.6
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    • pp.523-528
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    • 2015
  • In this paper, we propose a new multiresolutional and dynamic approach of the EM algorithm. EM is a very popular and powerful clustering algorithm. EM, however, has problems that indexes multiresolution data and requires a priori information on a proper number of clusters in many applications, To solve such problems, the proposed EM algorithm can impose a multiresolution kd-tree structure in the E-step and allocates a cluster based on sequential data. To validate clusters, we use a merge criteria for cluster merging. We demonstrate the proposed EM algorithm outperforms for texture image segmentation.

Mining the Up-to-Moment Preference Model based on Partitioned Datasets for Real Time Recommendation (실시간 추천을 위한 분할셋 기반 Up-to-Moment 선호모델 탐색)

  • Han, Jeong-Hye;Byon, Lu-Na
    • Journal of Internet Computing and Services
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    • v.8 no.2
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    • pp.105-115
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    • 2007
  • The up-to-moment dataset is built by combining the past dataset and the recent dataset. The proposal is to compute association rules in real time. This study proposed the model, $EM_{past'}$ and algorithm that is sensitive to time. It can be utilized in real time by applying partitioned combination law after dividing the past dataset into(k-1). Also, we suggested $EM^{ES}_{past}$ applying the exponential smoothing method to $EM^p_{past'}$ When the association rules of $EM_{past'}\;EM^w_{past'\;and\;EM^{ES}_{past}$ were compared, The simulation results showed that $EM^{ES}_{past}$ is most accurate for testing dataset than $EM_{past}$ and $EM^w_{past}$ in huge dataset.

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