• Title/Summary/Keyword: normalizing

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Normalization of Cone Resistance in Granular Soil (모래지반에서 콘 저항값의 정규화에 관한 연구)

  • Na Yung-Mook
    • Journal of the Korean Geotechnical Society
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    • v.20 no.9
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    • pp.33-45
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    • 2004
  • Sandfill at reclaimed sites is usually formed by more than one placement method. Reclaimed sandfill often shows highly variable profiles and the cone penetration test is most commonly used for site characterization. Correlations between cone resistance and geotechnical parameters for sand are influenced by in-situ stress level and it is important to incorporate stress level effect. In this study, cone penetration tests were performed at several elevations from the top of a 10m high surcharge, which was later removed step by step. In order to establish more reliable correlations between cone resistance and geotechnical parameters for sand, different ways of normalizing cone resistance by the corresponding in-situ vertical stress were investigated.

Probabilistic Evaluation of Fatigue Life in High Frequency Electric Resistance Welded Joint of the Pipe (고주파 전기저항용접부 강관에서의 피로수명의 확률론적 평가)

  • Seo, Young-Bum;Kim, Choong-Myeong;Kim, Chul-Su;Kim, Jung-Kyu
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.400-405
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    • 2004
  • In this study, the optimal welding condition of the input power was selected experimentally through the ERW simulator, which is equal to welding status of ERW part in pipe. This condition is the input power 250kW in the heat treatment of the $900^{\circ}C$ normalizing derived from the nondestructive technique and impact energy. In order to evaluate the variation of the fatigue life in the pipe, fatigue surface crack growth test of base and optimal welded metal were performed statistically. As stress intensity factor range (${\Delta}K_s$) increases, the fatigue crack propagation rate (da/aN) of the base metal is faster than that of the welded joint. The variation of the fatigue life in the ERW pipe was estimated statistically using Monte-Carlo simulation with the standard deviation of material constants (C and m) of the paris law in the specimen.

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Dynamic Modeling and Manipulability Analysis of Underwater Robotic Arms (수중로봇팔의 동역학 모델링과 동적 조작도 해석)

  • Jnn Bong-Huan;Lee Jihong;Lee Pan-Mook
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.8
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    • pp.688-695
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    • 2005
  • This paper describes dynamic manipulability analysis of robotic arms moving in viscous fluid. The manipulability is a functionality of manipulator system in a given configuration under the limits of joint ability with respect to the task required to be performed. To investigate the manipulability of underwater robotic arms, a modeling and analysis method is presented. The dynamic equation of motion of underwater manipulator is derived based on the Lagrange-Euler equation considering with the hydrodynamic forces caused by added mass, buoyancy and hydraulic drag. The hydrodynamic drag term in the equation is established as analytical form using Denavit-Hartenberg (D-H) link coordination of manipulator. Two analytical approaches based oil manipulability ellipsoid are presented to visualize the manipulability of robotic arm moving in viscous fluid. The one is scaled ellipsoid which transforms the boundary of joint torque to acceleration boundary of end-effector by normalizing the torques in joint space, while the other is shifted ellipsoid which depicts total acceleration boundary of end-effector by shifting the ellipsoid as much as gravity and velocity dependent forces in work space. An analysis example of 2-link manipulator with proposed analysis scheme is presented to validate the method.

Proposal of the Penalty Factor Equations Considering Weld Strength Over-Match

  • Kim, Jong-Sung;Jeong, Jae-Wook;Lee, Kang-Yong
    • Nuclear Engineering and Technology
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    • v.49 no.4
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    • pp.838-849
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    • 2017
  • This paper proposes penalty factor equations that take into consideration the weld strength over-match given in the classified form similar to the revised equations presented in the Code Case N-779 via cyclic elastic-plastic finite element analysis. It was found that the $K_e$ analysis data reflecting elastic follow-up can be consolidated by normalizing the primary-plus-secondary stress intensity ranges excluding the nonlinear thermal stress intensity component, $S_n$ to over-match degree of yield strength, $M_F$. For the effect of over-match on $K_n{\times}K_{\nu}$, dispersion of the $K_n{\times}K_{\nu}$ analysis data can be sharply reduced by dividing total stress intensity range, excluding local thermal stresses, $S_{p-lt}$ by $M_F$. Finally, the proposed equations were applied to the weld between the safe end and the piping of a pressurizer surge nozzle in pressurized water reactors in order to calculate a cumulative usage factor. The cumulative usage factor was then compared with those derived by the previous $K_e$ factor equations. The result shows that application of the proposed equations can significantly reduce conservatism of fatigue assessment using the previous $K_e$ factor equations.

A method for producing normalized total score of BSC measures (BSC 지표의 정규화된 Total Score 산출 방법)

  • Kim, Su-Yeon;Hwang, Hyun-Seok;Hong, Jong-Yi
    • Journal of Korea Society of Industrial Information Systems
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    • v.12 no.5
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    • pp.163-172
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    • 2007
  • ESC has been used as a tool for evaluating overall performance of firms. ESC focuses mainly on building a balanced viewpoint comprising perspectives and their metrics. It is, therefore, difficult to value overall strategic achievements of a company derived by consolidating various perspectives and metrics. Because of the absence of a method for consolidating ESC metrics and computing total score based on these metrics, it is difficult to evaluate whole strategic performance and find core obstacle parts of performance. In this paper, we suggest a method of normalizing a numerical value of metrics with different units, and calculating the total score of ESC metrics. We conduct a case study of evaluating the effectiveness of CRM to illustrate the applicability and feasibility of the suggested method.

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Efficiency Index Diagram for Wake Region Evaluation of Artificial Reefs Facilitated for Marine Forest Creation

  • Kim, Dongha;Jung, Somi;Na, Won-Bae
    • Journal of Advanced Research in Ocean Engineering
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    • v.2 no.4
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    • pp.169-178
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    • 2016
  • Recently, artificial reefs (ARs) have been frequently used primarily owing to the development in AR materials and projects for relatively complicated, large ARs. Among several engineering issues of ARs, wake region of an AR has been characterized because these regions have a high probability of recruiting seaweed spores, providing an energy saving zone, and facilitating deposition of sediments, nutrients, and bio-deposits. To characterize an efficiency index of an AR wake region and its dependency on the prevailing water flow directions, this study proposes a so-called efficiency index diagram. This characterization is done by normalizing the wake volumes with respect to the real AR volume and illustrating how efficiency indices vary with respect to the inlet flow directions. As a result, according to the diagram characteristics such as an averaged efficiency index, fundamental symmetric angle, secure angles, and principal directions, we can easily figure out how a target AR should be aligned along the main water flows to maximize the wake region around the AR. In addition, six ARs are considered and their efficiency index diagrams are illustrated to pinpoint the physical characteristics.

The Technology of Personal Cloud Computing and Market Research (퍼스널 클라우드 컴퓨팅의 기술과 시장 분석)

  • Shim, Hyun-Bo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.2
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    • pp.239-251
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    • 2014
  • The personal cloud is a service which approaches the personal contents scattering to all terminals and online space at the personal information-oriented age in which the person's digital device including the Smart-phone, MID, PC, IPTV and etc, increases and the personal online service including the blog, E-mail, UCC, social network service and ect, rapidly increasing for the cloud computing regardless of the terminal anywhere independently and can provide the high vale added personalization service through the analysis of the contents and processing. The future of the personal cloud market is prospected through the service and technology which enhances the understanding about the cloud computing, that is the next generation IT paradigm which the world IT companies pay attention to, and is provided and business strategy analysis of the security and normalizing and related companies.

PWSCC growth rate model of alloy 690 for head penetration nozzles of Korean PWRs

  • Kim, Sung-Woo;Eom, Ki-Hyun;Lim, Yun-Soo;Kim, Dong-Jin
    • Nuclear Engineering and Technology
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    • v.51 no.4
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    • pp.1060-1068
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    • 2019
  • This work aims to establish a model of a primary water stress corrosion crack growth rate of Alloy 690 material for the head penetration nozzles of Korean pressurized water reactors. The test material had an inhomogeneous microstructure with bands of fine-grains and intragranular carbides in the matrix of coarse-grains, which was similar to the archive materials of the head penetration nozzles. The crack growth rate was measured from the strain-hardened materials as a function of the stress intensity factor in simulated primary water at various temperatures and dissolved hydrogen contents. The effects of strain-hardening, temperature, and dissolved hydrogen on the crack growth rate were analyzed independently, and were then introduced as normalizing factors in the crack growth rate model. The crack growth rate model proposed in this work provides a key element of the tools needed to assess the progress of a stress corrosion crack when detected in thick-wall Alloy 690 components in Korean reactors.

Improving methods for normalizing biomedical text entities with concepts from an ontology with (almost) no training data at BLAH5 the CONTES

  • Ferre, Arnaud;Ba, Mouhamadou;Bossy, Robert
    • Genomics & Informatics
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    • v.17 no.2
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    • pp.20.1-20.5
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    • 2019
  • Entity normalization, or entity linking in the general domain, is an information extraction task that aims to annotate/bind multiple words/expressions in raw text with semantic references, such as concepts of an ontology. An ontology consists minimally of a formally organized vocabulary or hierarchy of terms, which captures knowledge of a domain. Presently, machine-learning methods, often coupled with distributional representations, achieve good performance. However, these require large training datasets, which are not always available, especially for tasks in specialized domains. CONTES (CONcept-TErm System) is a supervised method that addresses entity normalization with ontology concepts using small training datasets. CONTES has some limitations, such as it does not scale well with very large ontologies, it tends to overgeneralize predictions, and it lacks valid representations for the out-of-vocabulary words. Here, we propose to assess different methods to reduce the dimensionality in the representation of the ontology. We also propose to calibrate parameters in order to make the predictions more accurate, and to address the problem of out-of-vocabulary words, with a specific method.

The effect of cooling rates on carbide precipitate and microstructure of 9CR-1MO oxide dispersion strengthened(ODS) steel

  • Jang, Ki-Nam;Kim, Tae-Kyu;Kim, Kyu-Tae
    • Nuclear Engineering and Technology
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    • v.51 no.1
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    • pp.249-256
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    • 2019
  • The 9Cr-1Mo ferritic-martensitic ODS steel is a promising structural material for the next generation nuclear power plants including fast reactors for application in reactor vessels and nuclear fuel. The ODS steel was cooled down by furnace cooling, air cooling, oil quenching and water quenching, respectively, after normalizing it at $1150^{\circ}C$ for 1 h and then tempering at $780^{\circ}C$ for 1 h. It is found that grain size, a relative portion of ferrite and martensite, martensitic lath configuration, behaviors of carbide precipitates, and hardness of the ODS steel are strongly dependent on a cooling rate. The grain size and martensitic lath width become smaller with the increase in a cooling rate. The carbides were precipitated at the grain boundaries formed between the ferrite and martensite phases and at the martensitic lath interfaces. In addition, the carbide precipitates become smaller and more widely dispersed with the increase in a cooling rate, resulting in that the faster cooling rate generated the higher hardness of the ODS steel.