• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.60
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• pp.11-22
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• 2000

The main objective of this research is to analyze an order point and an order quantity of a distribution center and each branch to attain a target service level in multi-level inventory distribution system. In case of product item, we use the item with low volume of average monthly demand. Under the continuous review method, the distribution center places a particular order quantity to an outside supplier whenever the level of inventory reaches an order point, and receives the order quantity after elapsing a certain lead time. Also, each branch places an order quantity to the distribution center whenever the level of inventory reaches an order point, and receives the quantity after elapsing a particular lead time. When an out of stock condition occurs, we assume that the item is backordered. For considering more realistic situations, we use generic type of probability distribution of lead times. In the variable lead time model, the actually achieved service level is estimated as the expected service level. Therefore, this study focuses on the analysis of deciding the optimal order point and order quantity to achieve a target service level at each depot as a expected service level, while the system-wide inventory level is minimized. In addition, we analyze the order level as a maximum level of inventory to suggest more efficient way to develop the low demand item model.

• The Journal of Information Systems
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• v.26 no.4
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• pp.189-202
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• 2017

Purpose The purpose of this study is to find the factors for explaining the relationship between the satisfaction of IT consulting and entrepreneurship based on the corporate performance, financial and economic performance. Design/methodology/approach This study made a design of the research model by integrating the factors of entrepreneurship and satisfaction of IT consulting on the basis of ecosystem. In addition, this study, did empirical analysis of the structural equation model by PLS(Partial Least Squares) in order to find out the moderating effect of satisfaction of IT consulting on entrepreneurship. Findings According to the empirical analysis result, this study confirmed that the moderating effect of satisfaction of IT consulting on entrepreneurship, which increase the influence the effect of entrepreneurship on the corporate performance. However, the second order factor of enterprise ecosystem has no effect on the corporate performance. In addition, this study find out that the important role of IT consulting according to the change of business environment.

• Korean Journal of Poultry Science
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• v.28 no.3
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• pp.193-205
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• 2001

The most prevailing consumption pattern of chicken was "Buy fresh and cook at home (79.8%)". The frequency of eating chicken dish was about "Twice a month". Total average of degree of Preference is "2.30". It is very much close to "Like (2.0)" rather than "Average (3.0)". The degree of preference of chicken decrease as the age increase. About 30% of the housewives have the experience of buying chicken "Cut-up". But "Whole chicken (79.7%)" was still used mostly for chicken dish at home. As the education background improves or living expense increases, housewives purchase chicken "Cup-up" more frequently. The major criteria in purchasing chicken was "Hygiene (67.4%)""Quality (55.2%), "Expiration date (36.7%)" follows next. The groups of ′Above 50 years′, ′Graduate school′ and ′More than 3 million won′show greater interest about "Health" than any other groups. Major chicken dish at home in Korea was "Chopped hot chicken (70.7%)". "Boiled chicken soup (43.2%) \" and "Ginseng chicken soup (39.3%)" follows next. "Order for delivery (57.4%)" increased rapidly for chicken consumption. Croup of ′20~30 years′ order chickens for delivery more frequently than other groups. But as the age of housewives increases, they cook at home more frequently. The most preferred chicken dish for dining-out were "Fried chicken (69.4%)" and "Spicy chicken (57.4%)". The preference of Korean traditional dish for dining out was decreasing except "Chuncheon chicken rib (14.2%)".2%)".

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.11 s.158
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• pp.1618-1625
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• 2006

The purposes of this study were 1) to identify dimensions of fashion lifestyles of men of digital generation and online shopping mall service attributes, and 2) to find factors affecting general satisfaction and intention to purchase at online shopping malls. Data were obtained from 632 men aged between 15 and 39 who were using the internet. Fashion lifestyles produced five factors, fashion leadership, shopping enjoyment, brand pursuit, personality pursuit, and practicality pursuit. Internet service attributes included three factors, check-out service, after delivery service, and product presentation service. Significant determinants of general satisfaction were after delivery service, check-out service, product presentation service, and purchase experience in order. For intention to buy, after delivery service, check-out service, product presentation service, purchase experience, practicality, and household income level in order were significant. Finally, general satisfaction of purchase was a useful determinant of intention to buy. Implications were given for improving internet shopping mall services from the perspective of online fashion mall marketers.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.3
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• pp.1533-1556
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• 2017

The concept of trust in vehicular ad hoc networks (VANETs) is usually utilized to assess the trustworthiness of the received data as well as that of the sending entities. The quality of safety applications in VANETs largely depends on the trustworthiness of exchanged data. In this paper, we propose a self-organized distributed trust computing framework (DTCF) for VANETs to compute the trustworthiness of each vehicle, in order to filter out malicious nodes and recognize fully trusted nodes. The proposed framework is solely based on the investigation of the direct experience among vehicles without using any recommendation system. A tier-based dissemination technique for data messages is used to filter out non authentic messages and corresponding events before even going farther away from the source of the event. Extensive simulations are conducted using Omnet++/Sumo in order to investigate the efficiency of our framework and the consistency of the computed trust metrics in both urban and highway environments. Despite the high dynamics in such networks, our proposed DTCF is capable of detecting more than 85% of fully trusted vehicles, and filtering out virtually all malicious entities. The resulting average delay to detect malicious vehicles and fraudulent data is showed to be less than 1 second, and the computed trust metrics are shown to be highly consistent throughout the network.

• The Journal of Korean Physical Therapy
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• v.20 no.1
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• pp.23-31
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• 2008

Purpose: The purpose of this study was finding out the effects of spinal stabilization exercise using Centaur which is a 3D spinal stabilization sports implement on Chronic low back pain patients over 8 weeks. Methods: 30 patients with DDD were observed during the study. Their average age was 66.88years, height was 152.12cm and average weight was 58.91kg, 4 males and 26 females were involved. 8 various investigations were performed and varied values were compared with reinvestigation done after having exercised 8 weeks using 3-D CENTAUR We used VAS(visual analog scale) in order to see the variation of pain intensity, MOI(modified oswestry index) in order to see limitation of daily life. Results: VAS was lessened from 7.57 to 2.63, limitation of routine life(MOS) from 23.48 to 11.30, there were remarkable differences statistically(p<0.05). As a result of muscular investigation for static spinal stabilization by 8 variations of body deflection, muscular strength were all increased and there were signigicant differences statistically(p<0.05). Conclusion: It has turned out that pain and limitation of routine life was lessened, as a result of 8 weeks exercise using CENTAUR, and deep muscular power was increased. Thus it has turned out that 3-D spinal stabilization exercise has an effect on the strengthening spinal muscles and alleviation of their pain for old patients with DDD.

• International Journal of Reliability and Applications
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• v.7 no.1
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• pp.79-87
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• 2006

In this paper, some characterization results of the NBUCA class of life distributions are obtained. Behavior of the life distributions of the present class is developed in terms of the monotonicity of the residual life of k-out of-n systems given that the (n-k)th failure has occurred at time $t{\geq}0$. Similar conclusions based on the residual life of parallel system are also presented. Next, we focus upon the aging process of a system with independent but not necessarily identical NBUCA components. Finally, it is proved that if the lifetimes of a series systems with a random number of identical components have the NBUCA property then its units also have the same property.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.20 no.1
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• pp.17-35
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• 2016

In this study, the dynamic behaviour of a rotating Timoshenko beam when under the actions of a variable magnitude load moving at non-uniform speed is carried out. The effect of cross-sectional dimension and damping on the flexural motions of the elastic beam was neglected. The coupled second order partial differential equations incorporating the effects of rotary and gyroscopic moment describing the motions of the beam was scrutinized in order to obtain the expression for the dynamic deflection and rotation of the vibrating system using an elegant technique called Galerkin's Method. Analyses of the solutions obtained were carried out and various results were displayed in plotted curve. It was found that the response amplitude of the simply supported beam increases with an increase in the value of the foundation reaction modulus. Effects of other vital structural parameters were also established.

• Journal of the Korean Society of Visualization
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• v.8 no.2
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• pp.31-39
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• 2010

Hysteresis is an effect by which the order of previous events influences the order of subsequent events. Hysteresis phenomenon of supersonic internal flows with shock waves has not yet been clarified satisfactorily. In the present study, experiments are carried out on internal flow in a supersonic nozzle to clarify the hysteresis phenomena for the shock waves. Flow visualization is carried out separately on the straight and divergent channels downstream of the nozzle throat section. Results obtained were compared with numerically simulated data. The results confirmed hysteresis phenomenon for shock wave in the Laval nozzle at a certain specific condition. The relationship between hysteresis phenomenon and the range of the rate of change of pressure ratio with time was shown experimentally. The existence of hysteretic behavior in the formation, both the location and strength, of shock wave in the straight part of the supersonic nozzle with a range of pressure ratio has also been confirmed numerically.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.318-323
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• 2008

First aim of this study is to investigate consumer's actual value for environment related performance of house by using three different method, Ranking, Analytical Hierarchy Process (AHP) and Conjoint Analysis method. Second aim is to estimate consumers' monetary value about environment related factor through Marginal Willing to Pay(MWTP), and third aim is to find out the difference of values between the groups classified according to respondents' characteristics. A questionnaire survey was carried out in Seoul in order to clarify the preference and monetary value of four selected attributes. They are environmental performance, residents' health, home automation and increase of floor area. As a result, people showed high values in the order of health, environmental consideration, increase of floor area and home automation. Moreover, it was found out that MWTP for environmental performance and health are higher than market price. In addition, the group of high age and group of female showed high values for the reduction of $CO_2$ emission