• Title/Summary/Keyword: Adams

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NON-TRIVIALITY OF TWO HOMOTOPY ELEMENTS IN π*S

  • Liu Xiugui
    • Journal of the Korean Mathematical Society
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    • v.43 no.4
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    • pp.783-801
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    • 2006
  • Let A be the mod p Steenrod algebra for p an arbitrary odd prime and S the sphere spectrum localized at p. In this paper, some useful propositions about the May spectral sequence are first given, and then, two new nontrivial homotopy elements ${\alpha}_1{\jmath}{\xi}_n\;(p{\geq}5,n\;{\geq}\;3)\;and\;{\gamma}_s{\alpha}_1{\jmath}{\xi}_n\;(p\;{\geq}\;7,\;n\;{\geq}\;4)$ are detected in the stable homotopy groups of spheres, where ${\xi}_n\;{\in}\;{\pi}_{p^nq+pq-2}M$ is obtained in [2]. The new ones are of degree 2(p - 1)($p^n+p+1$) - 4 and 2(p - 1)($p^n+sp^2$ + sp + (s - 1)) - 7 and are represented up to nonzero scalar by $b_0h_0h_n,\;b_0h_0h_n\tilde{\gamma}_s\;{\neq}\;0\;{\in}\;Ext^{*,*}_A^(Z_p,\;Z_p)$ in the Adams spectral sequence respectively, where $3\;{\leq}\;s\;<\;p-2$.

Demosaicking Method using High-order Interpolation with Parameters (매개변수를 갖는 고차원 보간법을 이용한 디모자이킹 기법)

  • Lee, Yeon-Kyung;Yoo, Hoon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.9
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    • pp.1276-1282
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    • 2013
  • This paper presents a demosaicking method based on high-order interpolation with parameters. Demosaicking is an essential process in capturing color images through a single sensor-array. Thus, a lot of methods including the Hamilton-Adams(HA) method has been studied in this literature. However, the image quality depends on various factors such as contrast and correlation in color space; existing algorithms depend on test images in use. Consequently, a new test image set was suggested to develop demosaicking algorithms properly. According to previous studies, the HA method shows high performances with the new test data set. In this paper, we improve the HA method using high-order interpolation with parameters. Also, we provide an analysis and formulations for the proposed method. To evaluate our method, we compare our method with the existing methods both objectively and subjectively. The experimental results indicate that the proposed method is superior to the existing methods.

A Study on Active Suspension system Using Time Delay Control (시간지연 제어기법을 이용한 능동 현가시스템에 관한 연구)

  • Xuan, Dong-Ji;Kim, Jin-Wan;Zhang, Jing-Yi;Kim, Young-Bae
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.1219-1224
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    • 2007
  • This is Presents experimental results of a force tracking controller for a quarter-car suspension system. The active suspension system was decomposed into two loops. At the main loop, the desired force signal is calculate by using a standard LQ design process. The Time Delay Control(TDC) design technique is then used to design the force controller such that the desired force signal is achieved in a robust manner when actuator or other plant uncertainties are present. The ADAMS controls module was used to realize the joint simulation of ADAMS and MATLAB, of which the results showed that the TDC strategy is reasonable and feasible.

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Dynamic Analysis of a Helicopter Landing Gear with Considering Flexible Structural Modes (동체의 유연성을 고려한 헬기 착륙장치의 동특성 해석 연구)

  • Hyun, Young-O;Bae, Jae-Seoung;Kim, Young-Seok;Hwang, Jae-Up;Lim, Kyoung-Ho;Kim, Doo-Man;Kim, Tae-Wook;Hwang, Jai-Hyuk
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.15 no.4
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    • pp.33-37
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    • 2007
  • In this paper, a dynamic analysis of a helicopter landing gear with considering flexible structural modes has been investigated. The main body of the helicopter has been modeled as a flexible body using FEM code, then a few selected vibration modes of the helicopter main body have been used as basis for the dynamic analysis of the helicopter landing gear. The simulation of dynamic analysis was carried out on the base of ADAMS aircraft module. It has been found by a series of simulation that the flexible structural modes has a significant effect on the dynamic characteristics of helicopter landing gear as the flexibility of the main body is increased.

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Hysteretic Characteristics of Leaf Springs in Commercial Vehicles (상용차량용 판스프링의 이력특성 구현)

  • Moon, Won-Ki;Song, Chul-Ki
    • Transactions of the Korean Society of Automotive Engineers
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    • v.16 no.2
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    • pp.99-105
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    • 2008
  • Multi-leaf springs are widely used for a major suspension component in many commercial vehicles. The modeling technique of multi-leaf springs is one of the most difficult problems in suspension modeling as the elements have complicated nonlinear characteristics such as a hysteresis behavior due to the friction. In this paper, hysteretic characteristics with the static and dynamic test are modeled and are simulated with three links and joints in MSC.ADAMS. Simulation results showed good agreements with test results. Using this methodology, it is expected that dynamic characteristics of suspension system with multi-leaf spring can be more accurately evaluated in vehicle dynamics.

Life History, Ginseng Damage and Chemical Control of the Field Slug, Deroceras varsans A, Adams (들민달팽이의 생활사와 인삼의 피해 및 약제 방제)

  • 김기황;오승환
    • Journal of Ginseng Research
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    • v.14 no.3
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    • pp.421-426
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    • 1990
  • Field and laboratory works were conducted to Investigate the life history, ginseng damage and chemical control effect of the field slug, Deroceras varians A. Adams. D. varians laid eggs from April to June, but a small number of eggs were also found from July to September in the field. Most young slugs grew through the slimmer months to maturity by October. overwintered beneath the moist soil surface, and began feeding and egg-laying in the following April. indicating that D varians have a life cycle in a year. Damage of ginseng plants by D. varina occurred mainly from late April to mid May in the 3rd to 5th year ginseng fields with rice-straw mulching. It seems that this damage is caused by the adults in oviposition periods and related to rice-straw mulching of ginseng fields. In the experiment, ethoprop 5% granule and metaldehyde 6% bait showed relatively high effectiveness in the control of D. varians adults. Bordeaux mixture was more effective when the chemical was sprayed after infestation of the slug than before the infestation and when the 6-12 mixture was used.

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Breakthrough Characteristics for Lithium Ions Adsorption in Fixed-bed Column Packed with Activated Carbon by Modified with Nitric Acid (질산으로 개질한 활성탄을 충전한 고정층에서 리튬이온 흡착시의 파과특성)

  • Kam, Sang-Kyu;You, Hae-Na;Lee, Min-Gyu
    • Journal of Environmental Science International
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    • v.23 no.6
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    • pp.1143-1149
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    • 2014
  • The adsorption experiments of lithium ions were conducted in the fixed bed column packed with activated carbon modified with nitric acid. Effect of inlet concentration, bed hight and flow rate on the removal of lithium ions was investigated. The experimental results showed that the removal and the adsorption capacity of lithium ions increased with increasing inlet concentration, and decreased with increasing flow rate. When the bed height increased, the removal and the adsorption capacity increased. The breakthrough curves gave a good fit to Bohart-Adams model. Adsorption capacity and breakthrough time calculated from Bohart-Adams model, these results were remarkably consistent with the experimental values. The adsorption capacity was not changed in the case of 3 times repetitive use of adsorbent.

A Study on Multi-Axiles using ADAMS (ADAMS를 이용한 다축 시뮬레이터에 관한 연구)

  • 정찬범;유승환;이경백;김영배
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2001.04a
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    • pp.288-291
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    • 2001
  • Vehicle evaluation is performed on the proving ground, and durability test and dynamic test cost lots of money and time. Doing replace real vehicle experiment with similar experiment environment, it will take us much more useful advantages. Suspension simulator is required the robust and high-reliability and used widely. But it's natural of high-leveled control technique to manage to be fitted fluid system's property and complex that is for the lack of self-damping, nonlinearity, compressibility. In designing and evaluating simulator, it is important to understand the capability of kinematic and static performances. In this paper, an kinematic modeling and analysis has been presented using ADAMS to design that can reproduce longitudinal, lateral, and vertical force.

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Flexible Multibody Dynamic Analysis Using Multirate Integration Method (멀티레이트 수치적분법을 이용한 유연다물체 동역학해석)

  • Kim, Seong-Su;Kim, Bong-Su
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.11
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    • pp.2804-2811
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    • 2000
  • A Nordsick form opf the multirate integration scheme has been proposed for flexible multibody dynamic systems. It is assumed that vibrational modal coordinates in the equations of motion are treated as fast variables, whereas the relative joint coordinates are treated as slow variables. In the multirate integration, the fast variables are integrated with small step-size, and the slow variables are integrated with larger step-size. The proposed multirate integration method is based on the Adams-Bashforth-Moulton predictor-corrector method and implemented in the Nordsieck vector form. The Nordsieck form of multrate integration method provides effective step-size control and at the same time, inherits the efficiency from the Adams integration method. Simulations of a flexible gun and turret system of the military tank have been carried out to show the effectiveness and efficiency of the proposed method.