• Journal of Power System Engineering
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• v.17 no.1
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• pp.77-84
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• 2013

The proportional pressure control valve that was used to relief valve has different dynamic characteristics on each case. Because this valve has different assembling or processing error and environmental condition. However, a customer who used the relief valve wants to have a steadily performance even if the dynamic characteristics of valve was changed. For this reason, the manufacturer try to make the robust controller that has simple structure. This paper concerns about the design of robust controller that didn't affected by plant parameter's changing. The control strategy is a model reference control that conducted by on line identification problem, gradient method and Lyapunov equation. This adaptvie control law's validity that this paper deal with was confirmed by an results of step response test or hysteresis test.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.4
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• pp.93-99
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• 2008

The clutch is a subcomponent of the transmission that is designed to engage and disengage power flow between the engine and the transmission. Recently, the engine power of automobile has been continuously increased because of customer's demand for the bigger one. As the engine power is increased, the vibration transmitted to the hydraulic clutch operating system has been increased. Therefore the demand for the reduction of clutch pedal vibration during the operation of the clutch system has been increased. This paper describes the pressure pulsation reduction characteristics of the damper cylinder which is applied to the hydraulic clutch operating system. And the purpose of this study is to confirm the availability of a simulation model and investigating the test results of hydraulic clutch operating system. The test results are compared with the simulation results. Therefore it may be concluded that the simulation model and test results will be very useful f3r the design of hydraulic clutch damper cylinder.

• Safety and Health at Work
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• v.10 no.4
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• pp.476-481
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• 2019

Background: Mystery shopping is a method in which a company monitors quality of service and employee conduct and compliance with regulations using an evaluator posing as a customer. It is a typical tool of customer-centered bureaucratic control insofar as it provides overall and standardized evaluation of intangible elements of customer service as well as physical elements of service environments. The purpose of this study is to examine how mystery shopping is related to the health status of service workers in South Korea. Methods: Data from semistructured interviews with 15 workers were collected from January to April 2019 to obtain information on service worker experiences with mystery shopping. Data were analyzed using the constant comparison method. Results: Mystery shopping limits worker autonomy and stiffens the workplace environment by standardizing and monitoring labor processes for service workers. In addition, mystery shopping heightens work stress through increased labor intensity. Five mechanisms by which mystery shopping affects service worker health are identified and comprise (1) multifaceted and multilayered surveillance, (2) evaluator subjectivity and irrational requirements, (3) standardized rules combined with high pressure to achieve sales, (4) self-esteem degradation because of evaluator results, and (5) musculoskeletal disorders because of strict adherence to labor processes based on evaluator results. Conclusion: Mystery shopping as an evaluation method should be reconsidered not only in terms of health problems but also in terms of organizational efficiency and issues of human rights.

• Korean System Dynamics Review
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• v.12 no.1
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• pp.89-114
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• 2011

With steady increase in the demand for door-to-door delivery services, courier service providers are facing a constant pressure to reduce delivery price in order to secure quantity order and to improve the efficiency and reliability for customer service. The objective of this research is to explain the structure of the door-to-door delivery including door-to-door delivery service demand, sorting capacity in the hub-terminal, and the system performance measures such as service reliability networks using causal loop diagram(CLD). Based on causal relation, this research describes a comprehensive approach to examine how capacity reliability contributes to the renewal of the firm's competences through its reciprocal relationship with travel time reliability and connectivity reliability. Also, this research suggests the policy alternatives to improve effectiveness and efficiency of door-to-door delivery network in response to increase customer satisfaction and profit maximization of the courier service providers: operational, tactical, and strategic levels.

• Industrial Engineering and Management Systems
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• v.11 no.2
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• pp.155-164
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• 2012

As the global market becomes more competitive, manufacturing industries face relentless pressure caused by a growing tendency of greater varieties of products, shorter manufacturing cycles and more sophisticated customer requirements. Efficient and effective supplier selection and order allocation decisions are, therefore, important decisions for a manufacturer to ensure stable material flows in a highly competitive supply chain, in particular, when customers are willing to accept products with less desirable product attributes (e.g., color, delivery date) for economic reasons. This paper attempts to solve optimally the challenging problem of supplier selection and order allocation, taking into consideration the customer flexibility for a manufacturer producing multi-products to satisfy the customers' demands in a multi period planning horizon. A new mixed integer programming model is developed to describe the behavior of the supply chain. The objective is to maximize the manufacturer's total profit subject to various operating constraints of the supply chain. Due to the complexity and non-deterministic polynomial-time (NP)-hard nature of the problem, an improved genetic approach is proposed to solve the problem optimally. This approach differs from a canonical genetic algorithm in three aspects: a new selection method to reduce the chance of premature convergence and two problem-specific repair heuristics to guarantee feasibility of the solutions. The results of applying the proposed approach to solve a set of randomly generated test problems clearly demonstrate its excellent performance. When compared with applying the canonical genetic algorithm to locate optimal solutions, the average improvement in the solution quality amounts to as high as ten percent.

• Proceedings of the CALSEC Conference
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• 2004.02a
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• pp.117-121
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• 2004

Paradigm Shift： Business of government - Transition to egovernment · Citizens have become accustomed to the private sector delivering high standards of customer service on the Internet and expect government to do likewise(Schoeniger, 2000). · The rise of e-business in the private sector reinforce the shift in the focus of government(Alfred Tat-Kei). · Explosive growth in Internet usage and rapid development e-Business in the private sector have put growing pressure on the public sector to serve citizens electronically, which is often known as the "e-government" initiative(omitted)

• The Journal of Information Systems
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• v.8 no.2
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• pp.129-143
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• 1999

A great number of companies are currently examining the opportunities made available through the internet. This research aims to identify the factors that influence the adoption of the internet market. The innovation-IT-diffusion theory provide the theoretical foundation for this study. Seven factors were found to influence the adoption level of the internet market. They are top management support, cost efficiency, inclination toward new technology, absorptive capacity, institutional support, competitors move and customer pressure. Nonparametric test was used to test hypotheses. The results shows that top management support is the most important factor, and institutional support is not related to the adoption of the internet market.

• Journal of Information Technology Applications and Management
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• v.25 no.1
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• pp.105-124
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• 2018

The usage level of SMEs' win-win payment system is still lower than originally expected. In order to find the answer, we studied SMEs' usage performance of win-win payment system and analyzed the influencing factors of SMEs' usage level of win-win payment system. This study found that the more SMEs utilize win-win payment system, the higher they achieve the desired performance in finance, customer, process, learning and growth perspective. And this study found that usage level of win-win payment system is high in order of large corporations' pressure, government policy, and SMEs' readiness. This study is expected to improve win-win growth by increasing usage level of win-win payment system between large corporations and SMEs, while establishing desirable ecosystems.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.3
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• pp.151-158
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• 2008

The clutch system is a subcomponent of the transmission that is designed to engage and disengage power flow between the engine and the transmission. Recently, the engine power of automobile has been continuously increased because of customer's demand for the bigger one. As the engine power is increased, the vibration transmitted to the hydraulic clutch operating system has been increased. Therefore the demand for the reduction of clutch pedal vibration during the operation has been increased. This paper describes the pressure pulsation reduction characteristics of the damper cylinder which is applied to the hydraulic clutch operating system. And the purpose of this study is to propose an analysis model and investigate the effect of the design variable variations for the hydraulic clutch system. Especially, we studied the effect of damper cylinder parameter variations on the hydraulic clutch system performance.

• The Journal of the Korea Contents Association
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• v.10 no.6
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• pp.386-403
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• 2010

This research studied the impact of the customer orientation and job satisfaction by lowering the desire of the kind for customers and the desire for fulfillment as a result of emotional exhaustion of the consultant who performs emotion labor at the call center. This research sets study model and hypothesis to verify that call center consultant's emotional exhaustion how to effect customer orientation and job satisfaction. We took questionnaires from 157 call center(financial institutes) consultant's in Seoul for the verification of the hypothesis. I show that the consultant's emotional exhaustion had negatively affected the customer orientation and job satisfaction. In this paper proposed the importance that the experience of the consultant's emotional exhaustion who is the main agent of the performance should be minimized by removing ad improving the factors to lower emotion exhaustion through lowering time pressure in the work performance reduce the consultant's emotional exhaustion, granting work autonomy and authority, and active support of relevant departments and the ongoing communication between the managers and consultant This study makes a significant meaning in that it proposed the consultant's emotional exhaustion was negative factor on the customer orientation and job satisfaction factor in operating call center worker.