• Journal of the Korean Society for Aviation and Aeronautics
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• v.24 no.4
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• pp.44-52
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• 2016

The departure flow management is the planning tool to optimize the schedule of the departure aircraft and allows them to join smoothly into the overhead traffic flow. To that end, the arrival time prediction to the merge point for the cruising aircraft is necessary to determined. This paper proposes a trajectory prediction model for the cruising aircraft based on the machine learning approach. The proposed method includes the trajectory vectored from the procedural route and is applied to the historical data to evaluate the prediction performances.

• Journal of Information Processing Systems
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• v.7 no.2
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• pp.261-270
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• 2011

The IEEE 802.16 standard is supposed to provide a wide-range broadband wireless service, but it leaves the implementation of the wireless resource scheduler as an open issue. We have studied the scheduling problem and propose a two level scheduling (TLS) scheme with support for quality of service and fairness guarantees for downlink traffic in a WiMAX network. A central controller Base Station has a number of users, and each mobile subscriber station has different channel conditions. The same mobile subscriber station may have different service requirements at different times in the WiMAX network. Based on OPNET simulation, the results show our scheduling algorithm can increase the network throughput, maintain relative fairness, and lower delay over the round robin and weighted round robin algorithms.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.2
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• pp.114-126
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• 2009

In this paper, a versatile multi-criteria optimization concept for fatigue life prediction is introduced. Multi-criteria decision making in engineering design refers to obtaining a preferred optimal solution in the context of conflicting design objectives. Compromise decision support problems are used to model engineering decisions involving multiple trade-offs. These methods typically rely on a summation of weighted attributes to accomplish trade-offs among competing objectives. This paper gives an interpretation of the decision parameters as governing both the relative importance of the attributes and the degree of compensation between them. The approach utilizes a response surface model, the compromise decision support problem, which is a multi-objective formulation based on goal programming. Examples illustrate the concepts and demonstrate their applicability.

• Communications for Statistical Applications and Methods
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• v.20 no.6
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• pp.481-490
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• 2013

Classification is an important research area as data can be easily obtained even if the number of predictors becomes huge. The support vector machine(SVM) is widely used to classify a subject into a predetermined group because it gives sound theoretical background and better performance than other methods in many applications. The SVM can be viewed as a penalized method with the hinge loss function and penalty functions. Instead of $L_2$ penalty function Fan and Li (2001) proposed the smoothly clipped absolute deviation(SCAD) satisfying good statistical properties. Despite the ability of SVMs, they have drawbacks of non-robustness when there are outliers in the data. We develop a robust SVM method using a weight function with the SCAD penalty function based on the local quadratic approximation. We compare the performance of the proposed SVM with the SVM using the $L_1$ and $L_2$ penalty functions.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.3
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• pp.280-283
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• 2023

Objectives: The purpose of this study was to examine the change in exposure concentration in the cleaning process after installing a local exhaust system. Methods: Dichloromethane measurement was conducted according to the KOSHA Guide (A-19-2019). Results: After the local exhaust device was installed, a total of three measurements were conducted, including temporary work environment measurements, and all of the measurements did not exceed the DCM exposure standard, but were more than 50% of the DCM Time Weighted Average((8-TWA) Conclusions: It is thought that the local ventilation system of a small business needs not only support for the initial installation cost, but also educational support for maintaining the performance of the local ventilation system and support for consumables (adsorbents, filters, etc.) that incur periodic costs.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.4
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• pp.700-713
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• 2009

Most of any existing classification algorithm in data mining area have focused on goals improving efficiency, which is to generate decision tree more rapidly by utilizing just less computing resources. In this paper, we focused on the efficiency as well as effectiveness that is able to generate more meaningful classification rules in application area, which might consist of the ontology automatic generation, business environment and so on. For this, we proposed not only novel function with the weight of support and confidence degree but also analyzed the characteristics of the weighted function in theoretical viewpoint. Furthermore, we proposed novel classification algorithm based on the weighted function and the characteristics. In the result of evaluating the proposed algorithm, we could perceive that the novel algorithm generates more classification rules with significance more rapidly.

• The Korean Journal of Health Service Management
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• v.11 no.3
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• pp.79-90
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• 2017

Objectives : The purpose of this study was to identify the prevalence of malnutrition and to explore its association with socioeconomic and social support factors among Korean elderly in the community. Methods : The study sample was a weighted population of 10,160 elderly who participated in the 2014 Korean Elderly Living Conditions and Welfare Survey. Multiple logistic regression analyses were performed to assess the association socioeconomic and social support factors have with malnutrition. Results : Of the Korean elderly 18.6% were at risk of malnutrition. Being uneducated (OR=1.40) and having a lower household income (OR=1.97) were significantly associated with malnutrition even after adjusting for other socio-demographic and health-related covariates. Elderly who lived alone (OR=1.86) and who had poor relationships with their children (OR=1.97) were at much higher risk of malnutrition than their counterparts. Their having poor relationships with acquaintances and poor social participation were also associated with malnutrition. Conclusions : Socioeconomic and social support resources are important factors in the nutritional status of the elderly.

• Journal of the Korea Society of Computer and Information
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• v.16 no.11
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• pp.45-56
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• 2011

WBAN is short range wireless communication technology which is consists of several small devices close to, attached to or implanted into the human body. WBAN is classified into between medical and non-medical by applications based on technology and medical data with periodic characteristics is used the GTS method for transmitting data to guarantee the QoS. In this paper we proposed algorithm that resolve lack of GTSs while data transmit GTS method in superframe structure of WBAN. Coordinator dynamically allocates GTSs according to the data rate of devices and make devices share GTSs when lack of GTSs. We compared delay bounds, throughput for performance evaluation of the proposed algorithm. In other words, we proposed algorithm adaptive WFQ scheduling that GTS allocation support differential data rate in environments of WBAN. The experiment results show the throughput increased and the maximum delay decreased compared with Round Robin scheduling.

• Research in Community and Public Health Nursing
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• v.26 no.4
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• pp.372-379
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• 2015

Purpose: This research was conducted to examine the successful aging and identify factors influencing successful aging in the Korean elderly. Methods: The subjects were 4,507 elders and data were collected from the 4th Korean Longitudinal Study of Ageing in 2012. The data were analyzed using frequencies, weighted percentage, ${\chi}^2$ test, and logistic regression. Results: The results of this study showed that 19.6% of the participants were categorized to successful aging. The domains of the absence of disease and disability and maintaining physical and mental functioning showed a high rate of achievement, while the domain of active engagement with life showed a low rate of achievement compared to others. Successful aging was influenced by gender, age, subjective economic status, subjective health status, and family support, particularly spouse's support. Conclusion: Intervention programs to increase the prevalence of successful aging are required. Especially programs for strengthening spouse's support and enhancing subjective health status are required.

• Communications of the Korean Mathematical Society
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• v.29 no.3
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• pp.409-413
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• 2014

In this paper, we study some quantity equivalent to the norm of Bloch to $A^p_{\alpha}$ composition operator where Ap $A^p_{\alpha}$ is the weighted Bergman space on the unit ball of $\mathbb{C}^n$ (0 < p < ${\infty}$ and -1 < ${\alpha}$ < ${\infty}$).