• Title/Summary/Keyword: free A-module

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ON GRAPHS ASSOCIATED WITH MODULES OVER COMMUTATIVE RINGS

  • Pirzada, Shariefuddin;Raja, Rameez
    • Journal of the Korean Mathematical Society
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    • v.53 no.5
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    • pp.1167-1182
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    • 2016
  • Let M be an R-module, where R is a commutative ring with identity 1 and let G(V,E) be a graph. In this paper, we study the graphs associated with modules over commutative rings. We associate three simple graphs $ann_f({\Gamma}(M_R))$, $ann_s({\Gamma}(M_R))$ and $ann_t({\Gamma}(M_R))$ to M called full annihilating, semi-annihilating and star-annihilating graph. When M is finite over R, we investigate metric dimensions in $ann_f({\Gamma}(M_R))$, $ann_s({\Gamma}(M_R))$ and $ann_t({\Gamma}(M_R))$. We show that M over R is finite if and only if the metric dimension of the graph $ann_f({\Gamma}(M_R))$ is finite. We further show that the graphs $ann_f({\Gamma}(M_R))$, $ann_s({\Gamma}(M_R))$ and $ann_t({\Gamma}(M_R))$ are empty if and only if M is a prime-multiplication-like R-module. We investigate the case when M is a free R-module, where R is an integral domain and show that the graphs $ann_f({\Gamma}(M_R))$, $ann_s({\Gamma}(M_R))$ and $ann_t({\Gamma}(M_R))$ are empty if and only if $$M{\sim_=}R$$. Finally, we characterize all the non-simple weakly virtually divisible modules M for which Ann(M) is a prime ideal and Soc(M) = 0.

Buoyancy Engine Independent Test Module Test in the the Deep Ocean Engineering Basin and at Sea (부력엔진 독립시험 모듈 심해공학수조 시험과 실해역 시험)

  • Chong-Moo Lee;Hyungwoo Kim;Heung Hyun Lim
    • Journal of the Korean Society of Industry Convergence
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    • v.27 no.3
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    • pp.629-634
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    • 2024
  • The Korea Research Institute of Ships and Ocean Engineering (KRISO) has developed a test module that can vertically ascend and descend with a buoyancy engine to verify the performance of the developed buoyancy engine. The independent test module has been tested in the Ocean Engineering Basin(C.M.Lee et al., 2023). After that, more tests were performed in the Deep Ocean Engineering Basin and at sea. In the 50-meter depth pit test of the Deep Ocean Engineering Basin, there were no problems with the ascent and descent operations, but the buoyancy engine was not properly maintained due to various problems in the independent test module, resulting in a difference between the calculated results using the solution of the equations of motion and the actual measurement results. The East Sea test was conducted at a depth of approximately 110 meters north-east of Pohang, with a dive to 100 meters. The difference between the pressure sensor value and the calculated value was observed, but after checking the results of the underwater position tracking device(USBL, Ultra Short Base Line system), it was estimated that the difference was caused by the influence of the current.

A development of design, performance and flow.noise analysis program (축류홴 설계, 성능, 유동/소음 해석 프로그램 개발)

  • KIM, C. J.;Baek, S. J.;Jeon, W. H.
    • 유체기계공업학회:학술대회논문집
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    • 2001.11a
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    • pp.43-47
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    • 2001
  • A program to design an axial flow fan, analyze the performance and predict the noise was developed. In order to develop the low noise fan, that program is compulsory. This software is composed of three parts : the geometric design module, the performance analysis module, the fan noise prediction module. In order to analyze the performance, three dimensional vortex panel method is used. The unsteady flow field was analyzed by time-marching free wake method. The unsteady force data is then used in predicting the noise. Farassat's equation is used to predict the noise of fan.

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A Note on E-Learning Dynamic Assessment with Fuzzy Estimations

  • Orozova Daniela;Kim Tae-Kyun;Kim Yung-Hwan;Park Dal-Won;Seo Jong-Jin;Atanassov Krassimir;Kang Dong-Jin;Rim Seog-Hoon;Jang Lee-Chae;Ryoo Cheon-Seoung
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.5 no.3
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    • pp.179-182
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    • 2005
  • A model of an assessment module has been created, using intuitionistic fuzzy estimations, which render account on the knowledge of the trained objects. The final mark is determined on the basis of a set of evaluation units. An opportunity is offered no only fur tracing the changes of the parameters of the trainer object, but there is also an opportunity of tracing the status of the already comprehended knowledge, as well as evaluating and changing the training themes and evaluation criteria.

Certain exact complexes associated to the pieri type skew young diagrams

  • Chun, Yoo-Bong;Ko, Hyoung J.
    • Bulletin of the Korean Mathematical Society
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    • v.29 no.2
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    • pp.265-275
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    • 1992
  • The characteristic free representation theory of the general linear group has found a wide range of applications, ranging from the theory of free resolutions to the symmetric function theory. Representation theory is used to facilitate the calculation of explicit free resolutions of large classes of ideals (and modules). Recently, K. Akin and D. A. Buchsbaum [2] realized the Jacobi-Trudi identity for a Schur function as a resolution of GL$_{n}$-modules. Over a field of characteristic zero, it was observed by A. Lascoux [6]. T.Jozefiak and J.Weyman [5] used the Koszul complex to realize a formula of D.E. Littlewood as a resolution of schur modules. This leads us to further study resolutions of Schur modules of a particular form. In this article we will describe some new classes of finite free resolutions associated to the Pieri type skew Young diagrams. As a special case of these finite free resolutions we obtain the generalized Koszul complex constructed in [1]. In section 2 we review some of the basic difinitions and properties of Schur modules that we shall use. In section 3 we describe certain exact complexes associated to the Pieri type skew partitions. Throughout this article, unless otherwise specified, R is a commutative ring with an identity element and a mudule F is a finitely generated free R-module.e.

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Development of Contents Platform for Bus Tour Service based on the bus stop (버스관광 서비스 제공을 위한 버스정류소 기반 콘텐츠 플랫폼 개발)

  • Kim, Min-Kyo;Kim, Sang-Hoon
    • Journal of Digital Contents Society
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    • v.19 no.6
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    • pp.1091-1096
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    • 2018
  • The purpose of this paper is to provide a convenient platform for bus users and a platform to provide tourist services suitable for bus tourism as integrated services. Recently, the number of FIT tourists for recreational purposes using public transportation is increasing as the bus use environment is improved. Accordingly, we need a tourist platform that meets the needs of tourists. In particular, a bus information providing algorithm is implemented using a bus information public API to more conveniently use the bus information providing system, and a user use behavior data collection module and a data mining module To develop a contents platform based on a bus stop for bus tourism services to FIT tourists using public transportation.

Buoyancy Engine Independent Test Module Test in the Ocean Engineering Basin (부력엔진 독립시험 모듈 해양공학수조 시험)

  • Chong-Moo Lee;Hyung-Woo Kim;Tae-Hwan Joung
    • Journal of the Korean Society of Industry Convergence
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    • v.26 no.6_2
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    • pp.1155-1162
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    • 2023
  • The Korea Research Institute of Ships and Ocean Engineering (KRISO), which is developing the core technology for the buoyancy engine of underwater gliders, has developed a test module that can vertically ascend and descend with a buoyancy engine to verify the performance of the developed buoyancy engine. The independent test module was tested in a 15 metre deep pit in the Ocean Engineering Basin to verify its ability to ascend and descend. In order to test at a shallower depth than the real sea, it was necessary to know the negative buoyancy value during descent and the time at which the buoyancy engine would be activated. To do this, we solved the equation of motion in the vertical direction to obtain these values and applied them to the tank test. To validate the usefulness of solving the equation, we also compared the depth of descent over time measured in the test with the results calculated from the solution.

Design of a Free Bulge Test Coil Using Electromagnetic Forces and Comparison between Experimental and Numerical Results (전자기력 자유벌지 실험을 위한 성형코일 설계 및 3-D 해석비교)

  • Kim, H.K.;Noh, H.G.;Kang, B.S.;Kim, J.
    • Transactions of Materials Processing
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    • v.23 no.7
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    • pp.431-438
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    • 2014
  • For electromagnetic forming(EMF) the most important feature is a forming coil which creates the electromagnetic force(Lorentz force), using current density and a magnetic field. Most previous papers have concentrated on the final configuration of the blank or the efficiency of EMF process. Studies focused on the design parameters affected by the forming coil performance have not been conducted. In order to design a suitable forming coil for an object, the current study uses LS-DYNA EM-Module to not only optimize the coil but also to examine the effect of coil performance. By this method a suitable forming coil was made and tested to determine whether or not good formability was achieved in a free bulge test Numerical analysis was also used. The workpiece was Al 1100-O with a thickness of 1.27mm and the coil was made from copper CW004A, which has good electrical conductivity and is suitable for electrical components.