• International Journal of Railway
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• v.2 no.4
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• pp.147-151
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• 2009

Railway vehicles equipped with semi-active suspension system can improve the ride quality of car bodies. Semi-active suspension system is usually applied onto high speed train, and therefore higher running safety requirement is proposed. The influence of semi-active suspension system on safety of vehicles running on straight line and curve line is studied, and the influences of sky hook damping coefficient and system time-delay on operation safety of cars fitted with semiactive suspension system is analyzed. The results show that the vehicles equipped with semi-active suspension system, not only the vibration of car body is decreased, it can also give little influence on running safety of cars, as a result, it will not endanger the running safety of cars.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.4
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• pp.147-153
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• 2002

In the preceding research, the active balancing device, which is an electro-magnetic type, has been developed and active balancing method using influence coefficient method is also proposed. The stability of active balancing control is studied in this paper. A stable condition for active balancing control is derived by estimating errors of influence coefficients. A gain scheduling control using influence coefficients of the reference model is proposed when dynamic characteristic of rotor system is changed. The stability of the balancing method is verified by experiments.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.3 s.96
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• pp.297-305
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• 2005

A high-speed spindle can be very sensitive to rotating mass unbalance which has harmful effect on many machine tools. Therefore, the balancing procedure to reducevibration in rotating system is certainly needed for all high-speed spindles. An active balancing program using influence coefficient method and an active balancing device of an electro-magnetic type have been applied to the developed high-speed spindle system in this study. A reliable gain-scheduling control using influence coefficients of the reference model although system characteristics are changed is applied. The stability of reference influence coefficients is verified by frequency response functions. The active balancing experiment for the developed high-speed spindle during operation is well performed with an active balancing program and device. As a result, controlled unbalance responses are below the vibration limit at all rotating speed ranges with critical speed.

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.4
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• pp.1-17
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• 2021

This study was examined whether the experiential marketing factors proposed by Bernd Schmitt were applicable to the consumer behavior of active seniors. The study was analyzed the influence of SEMs have on value perception of brand and attitude formation as well as the behavioral intentions of active senior consumers and whether this effect differed between the level of commitment. For empirical analysis, frequency analysis, EFA, reliability, CFA, SEM, and multiple-group comparison analysis were performed. The results showed that sense and feel factor did not have a significant influence on the value perception of brand, while think factor had a positive effect on the value perception of brand. Act factor did not affect the value perception of brand; on the other hand, relate factor had a significant effect on the value perception of brand. The result of structural equation modeling also revealed that the value perception of brand had a positive influence on attitude formation and behavioral intentions. The result of multiple-group comparison analysis confirmed that the influence of act factor on value perception of brand differed according to the level of commitment, but the positive influence of act factor on value perception of brand was limited to the high-level of commitment group. As a result of the influence relate factor had on the value perception of brand, differences existed between the two groups, and the low-level of commitment group had a greater influence than the high-level of commitment group. So it will be effective for active senior consumers to form fashion communities and let them participate in to enhance positive consumer behavior toward fashion brands.

• International Journal of Railway
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• v.3 no.2
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• pp.68-72
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• 2010

Railway vehicles equipped with semi-active suspension system can improve the ride quality of car bodies. Semi-active suspension system is usually applied onto high speed train, and therefore higher running safety requirement is desirable. The influence of semi-active suspension system on safety of vehicles running on straight line and curve line is studied, and the influences of sky hook damping coefficient and system time-delay on operational safety of cars fitted with semiactive suspension system is analyzed. The results show that in vehicles equipped with semi-active suspension system, while the vibration of car body is decreased, the running safety of cars is not affected to any significant degree. As a result, the ride quality is much improved with negligible deterioration of the running safety of cars.

• The Southeast Asian review
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• v.21 no.2
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• pp.217-261
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• 2011

This study is an attempt to construct a basic framework of analysis about China's political and economic influence on Southeast Asia through traditional Sinocentrism, anti-colonial nationalism, Cold War socialism and post-Cold War capitalism. As to the historical status of Southeast Asia vis-a-vis external forces such as India, China and the West, the colonial discourse tends to put excessive emphasis upon its dependence, and the posy-colonial discourse upon its autonomy. However, this study elucidates the political and economic interactions between China and Southeast Asia in a dynamic perspective, focusing on their reciprocal interactions beyond the essentially static dichotomy of autonomy and dependence. Chinese influence on Southeast asia can be divided into active and reactive one, with the former referring to direct and intended consequences and the latter to indirect and unintended consequences. In the historical process of active and reactive influence, both China and Southeast Asia were fundamentally proactive actors. Thus, the autonomy or dependence of Southeast Asia is just a question of relative one, with its actual extent and degree varying with specific spatial and temporal conditions.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.8
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• pp.48-53
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• 2001

In order to increase productivity and efficiency, high-speed rotating machines become popular these days. The high-speed rotating machine is likely to vibrate and cause machine failure even though it has small unbalance. Therefore, a balancing technique is studied in this paper. Off-line balancing methods are inadequate to solve unbalance vibration problem occurring in the field due to flexible rotor effect, faster tool change, and shorter spin-up and down, etc. An active balancing is suggested to allow re-balancing of the entire rotating assembly in the machine when a tool is changed. This paper shows how to identify the dynamics of the system using influence coefficient and suggest an active balancing technique based on influence coefficient method for high-speed spindle system.

• Smart Structures and Systems
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• v.3 no.4
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• pp.405-422
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• 2007

A new hybrid damping technique for vibration reduction in flexible structures, wherein a combination of layers of hard passive damping alloys and active (smart) magnetostrictive material is used to reduce vibrations, is proposed. While most conventional vibration control treatments are based exclusively on either passive or active based systems, this technique aims to combine the advantages of these systems and simultaneously, to overcome the inherent disadvantages in the individual systems. Two types of combined damping systems are idealized and studied here, viz., the Noninteractive system and the Interactive system. Frequency domain studies are carried out to investigate their performance. Finite element simulations using previously developed smart beam elements are carried out on typical metallic and laminated composite cantilever beams treated with hybrid damping. The influence of various parameters like excitation levels, frequency (mode) and control gain on the damping performance is investigated. It is shown that the proposed system could be used effectively to dampen the structural vibration over a wide frequency range. The interaction between the active and passive damping layers is brought out by a comparative study of the combined systems. Illustrative comparisons with 'only passive' and 'only active' damping schemes are also made. The influence and the mode dependence of control gain in a hybrid system is clearly illustrated. This study also demonstrates the significance and the exploitation of strain dependency of passive damping on the overall damping of the hybrid system. Further, the influence of the depthwise location of damping layers in laminated structures is also investigated.

• Journal of Power Electronics
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• v.15 no.1
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• pp.106-115
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• 2015

This paper proposes a novel direct power control (DPC) strategy for neutral-point-clamped (NPC) three-level rectifiers, to directly control the active power, the reactive power and the neutral point potential of the rectifiers by referring to three pre-calculated vector influence tables and minimizing an objective function. In the three vector influence tables, the influences of different voltage vectors on the active power, the reactive power and the neutral-point potential are shown explicitly. A conceptual description and control algorithm of the proposed controller are presented in this paper. Then, numerical simulations and experiments are carried out to validate the proposed method. Both the simulation and experimental results show that good performances during both the steady-state and transient operating conditions are achieved. As a result, the proposed strategy has been proven to be effective for NPC three-level rectifiers.

• Journal of Korea Game Society
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• v.22 no.1
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• pp.99-108
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• 2022

Despite the widespread use of digital games as a means of promoting physical activity, little is known about the factors that affect active video gaming. Based on the ecological model of health behavior, this study examined how personal, environmental, and social factors would influence active video gaming and general physical activity. The results showed that while all three factors significantly influence general physical activity, social factor is the only factor that affects active video gaming. The finding highlights the importance of social factors in predicting the use of active video games.