• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.14 no.4
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• pp.225-247
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• 2010

In this paper, we establish a two-competitive-prey and one-predator Holling type II system by introducing a proportional periodic impulsive harvesting for all species and a constant periodic releasing, or immigrating, for the predator at different fixed time. We show the boundedness of the system and find conditions for the local and global stabilities of two-prey-free periodic solutions by using Floquet theory for the impulsive differential equation, small amplitude perturbation skills and comparison techniques. Also, we prove that the system is permanent under some conditions and give sufficient conditions under which one of the two preys is extinct and the remaining two species are permanent. In addition, we take account of the system with seasonality as a periodic forcing term in the intrinsic growth rate of prey population and then find conditions for the stability of the two-prey-free periodic solutions and for the permanence of this system. We discuss the complex dynamical aspects of these systems via bifurcation diagrams.

• Journal of the Korean Home Economics Association
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• v.41 no.12
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• pp.103-116
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• 2003

It's very important to control their buying impulse for consumers surrounding in the very aggressive marketing strategies and materialistic socio-economic system. This study was to explore consumer's strategies to resist their buying impulses. The results from content analysis of interview data show various strategies and very similar to the self-control strategies of literature. The pre-stage strategies to resist buying impose were avoidances marketing strategies, pre-commitments, searching informations and bringing shopping lists and etc. The post-stage strategies were suspicions about marketing messages, considerations of negative outcomes, postponements, economic cost assessments, substitutions and etc. Developments and assessments of education programs to enhance consumer's self-control were needed.

• Journal of Drive and Control
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• v.10 no.1
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• pp.1-6
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• 2013

The paper describes a technique that compensates a friction in pneumatic cylinder to perform the position control. The friction is one of the most common nonlinearities present in pneumatic actuating systems. For accurate position control and low velocity control, control strategies usually rely on accurate estimation of friction. This paper presents a observer to estimate the friction force in the pneumatic cylinder from the pressures in cylinder chambers. Also, the stiction compensation of a pneumatic cylinder is obtained by adding pulses to the control signal using impulsive control. The characteristics of the pulses in impulsive control are determined from the control action. The simulation results are proved that the method proposed here is effective.

• Korean Journal of Childcare and Education
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• v.14 no.3
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• pp.59-76
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• 2018

Objective: The purpose of this study was to examine the relationships among teachers' resilience, difficulty in emotional regulation, and teaching strategies for behavior problems of children. Methods: A total of 200 day care and kindergarten teachers were surveyed. The collected data were analyzed by Pearson's correlation and multiple regression. Results: First, teachers' resilience, difficulty in emotional regulation and teaching strategies for children with behavior problems were significantly related. Teachers' resilience showed a positive correlation with teachers' positive prevention and reaction strategies but showed a negative correlation with teachers' negative reaction strategies. Among the teachers' difficulty in emotional regulation, the factor of difficulty for impulsive control and lack of attention showed negative correlations with teachers' prevention and positive reaction strategies. Second, teachers' resilience and difficulty in emotional regulation significantly explained the teaching strategies for children with behavior problems. Teachers' resilience was found to be the most important variable explaining teaching strategies for children with behavior problems. Conclusion/Implications: This study revealed that teachers' resilience and difficulties in emotional regulation were important psychological and emotional characteristics for teachers when teaching children with behavior problems.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.1
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• pp.58-68
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• 1999

The entry compression wave, which forms at the entrance of a high-speed railway tunnel, is closely related to the pressure transients in the train/tunnel systems as well as an impulsive noise appearing at the exit of the tunnel. In order to alleviate such undesirable phenomena, some control strategies have been applied to the compression wave propagating inside the tunnel. The objective of the current work is to investigate the effect of tunnel entrance hoods on the entry compression wave at the vicinity of the tunnel entrance. Three types of entrance hoods were tested by the numerical method using the characteristics of method for a wide range of train speeds. The results show that the maximum pressure gradient of compression wave can be considerably reduced by the tunnel entrance hood. Optimum hood shape necessary to reduce the pressure transients and impulsive noise was found to be of an abrupt type hood with its cross-sectional area 2.5 times the tunnel area. It is believed that the current results are highly useful in predicting the effects of entrance hoods and in choosing the shape of proper hood.

• Journal of Distribution Science
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• v.16 no.9
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• pp.59-63
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• 2018

Purpose - It has already been proved that 'mood' as the physical environment of shopping affects consumers' main sensory channels such as sight, hearing, smell, touch. However, there is no consensus on how the olfactory cue influences the customers in the shopping environment. In this study, we examine the previous studies on how the olfactory cue affects the customers in the shopping environment and present a clear direction as a suggestion for progressive research. Research design, data, and methodology - It is not important to use a lot of unconditional fragrance, but it should be exposed to the environment that suits the proper fragrance. In recent years, meaningful research on store fragrance has been slowly increasing. As a result, studies on the fragrance effects of retail stores have been conducted to verify the relevance of fragrance suitability in stores and consumer spending scale. Results - The fragrance appropriate for each store can not be uniformly specified as any fragrance. This is because external variables such as time, season, temperature, lighting, density of shoppers, and music in the store also affect customer evaluation. For example, using an unsuitable fragrance may encourage customers to leave the store quickly by restraining impulsive purchases or by disturbing concentration. The store manager should also be interested in using fragrances that are proven and effective in the store environment, but they should also have the ability to easily manipulate and manage the fragrances very appropriately according to changes in the store environment. Store managers should observe consumer preferences and responses according to their goals and strategies, and then systematically manage and store information about the fragrance appropriate to the store. Conclusions - In the future, the fragrance marketing researcher needs to consider the spatial form and density of the customer. In practice, managers operating a retail store should check the most appropriate store density(congestion) according to the size and spatial characteristics of the store and maintain the ideal conditions. To do this, it is necessary to pay attention to how to select and control sensory elements such as fragrance(olfactory), music(auditory), and lighting(visual).

• Korea Science and Art Forum
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• v.31
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• pp.105-118
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• 2017

The purpose of study is to examine the effectiveness of exhibition sales promotions and purchase intention for reasonable visitors. Perceived behavior control determining moderating effects on the relationship among their sales promotions and purchase intention is used as a predictive variable of unexpected impulsive purchases or negative purchase intention contrary to business intention. A total of 315 visitors who experienced the sales promotions of G-Star 2016 in Busan respond to the questionnaire and 259 forms are used to analyze the data. The main results of this study were as follows. First, except to value-added sales promotion, all of sales promotions positively impact on visitors' purchase intention. Second, as a result of analyzing the moderating effects of the perceived behavioral control consisting of control belief and perceived power on the relationships among the sales promotions and purchase intention, the control belief moderated the sales promotions such as price-off and education on purchase intention. In addition, the perceived power moderated the sales promotions such as escape and entertainment on purchase intention. In a nutshell, the degree of perceived behavior control makes critically impact on the effectiveness of exhibition sales promotions. Based on this results, it yields new insights into the way of developing various sales promotion strategies according to different features of visitors.