• Journal of Information Processing Systems
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• v.16 no.1
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• pp.210-223
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• 2020

Since constrained optimization algorithms are easy to fall into local optimum and their ability of searching are weak, an improved symbiotic organisms search algorithm with mixed strategy based on adaptive ε constrained (ε_SOSMS) is proposed in this paper. Firstly, an adaptive ε constrained method is presented to balance the relationship between the constrained violation degrees and fitness. Secondly, the evolutionary strategies of symbiotic organisms search algorithm are improved as follows. Selecting different best individuals according to the proportion of feasible individuals and infeasible individuals to make evolutionary strategy more suitable for solving constrained optimization problems, and the individual comparison criteria is replaced with population selection strategy, which can better enhance the diversity of population. Finally, numerical experiments on 13 benchmark functions show that not only is ε_SOSMS able to converge to the global optimal solution, but also it has better robustness.

• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.444-446
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• 2003

This paper deals with an allocation strategy for the resources of direct load control program, which is considered the operating states in power systems. The existing approaches, load shedding priority algorithm, curtailment payback based algorithm and mixed curtailment algorithm, are based on the uniform allocation strategy. These approaches are not taken into account the operating states in power systems. So, under the critical operating condition, direct load control resource is evaluated by introducing the congestion factor.

• Journal of the Korea Society of Computer and Information
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• v.24 no.1
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• pp.167-178
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• 2019

In this paper, we study the multi-objectives vehicle and drone routing problem with time windows, MOVDRPTW for short, which is defined in an urban delivery network. We consider the dual modal delivery system consisting of drones and vehicles. Drones are used as a complement to the vehicle and operate in a point to point manner between the depot and the customer. Customers make various requests. They prefer to receive delivery services within the predetermined time range and some customers require fast delivery. The purpose of this paper is to investigate the effectiveness of the delivery strategy of using drones and vehicles together with a multi-objective measures. As experiment datasets, we use the instances generated based on actual courier delivery data. We propose a hybrid multi-objective evolutionary algorithm for solving MOVDRPTW. Our results confirm that the vehicle-drone mixed strategy has 30% cost advantage over vehicle only strategy.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.761-771
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• 2020

This study discusses the role of Board Monitoring Effectiveness (BME) on managers' decisions regarding the business strategies that fit the external business environmental conditions by using a contingency analysis approach. Furthermore, this study will examine how fit strategies affect Sustainability Reporting (SR) of listed companies on the Indonesia Stock Exchange (IDX) from 2014 to 2017. This study uses Conditional Mixed Process (CMP) technique. This CMP method is claimed to be more efficient in analyzing the TSL models. This study found that in highly uncertain conditions, BME had a positive influence on the probability of managers to choose prospector and defender strategies rather than analyzers. These results indicate that BME shows positive impact on the contingency fit between business strategies and environmental uncertainty. In addition, the study documents that only prospectors have a positive impact on SR, however this study failed to document that defenders have positive impact on SR. Meanwhile the unexpected result is analyzers have a significantly positive effect on SR. This study is the first study to investigate the role of BME in contingency fit between business strategies and environmental uncertainties and how it produces effects up to the level of SR.

• Journal of Korean Academy of Nursing
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• v.44 no.6
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• pp.682-696
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• 2014

Purpose: This study was conducted to develop and test the effects of an emotional intelligence program for undergraduate nursing students. Methods: The study design was a mixed method research. Participants were 36 nursing students (intervention group: 17, control group: 19). The emotional intelligence program was provided for 4 weeks (8 sessions, 20 hours). Data were collected between August 6 and October 4, 2013. Quantitative data were analyzed using Chi-square, Fisher's exact test, t-test, repeated measure ANOVA, and paired t-test with SPSS/WIN 18.0. Qualitative data were analyzed using content analysis. Results: Quantitative results showed that emotional intelligence, communication skills, resilience, stress coping strategy, and clinical competence were significantly better in the experimental group compared to the control group. According to the qualitative results, the nursing students experienced improvement in emotional intelligence, interpersonal relationships, and empowerment, as well as a reduction in clinical practice stress after participation in the emotional intelligence program. Conclusion: Study findings indicate that the emotional intelligence program for undergraduate nursing students is effective and can be recommended as an intervention for improving the clinical competence of undergraduate students in a nursing curriculum.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.7
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• pp.833-839
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• 2018

This paper presents an analysis and the methodology of optimal operation strategy of the ESS(Energy Storage System) for reduce electricity charges. Electricity charges consist of a basic charge based on the contract capacity and energy charge according to the power usage. In order to use electrical energy at minimal charge, these two factors are required to be reduced at the same time. QP(Quadratic Programming) is appropriate for minimization of the basic charge and LP(Linear Programmin) is adequate to minimize the energy charge. However, the integer variable have to be introduced for modelling of different charge and discharge efficiency of ESS PCS(Power Conversion System), where MILP(Mixed Integer Linear Programming) can be used. In this case, the extent to which the peak load savings is accomplished should be assumed before the energy charge is minimized. So, to minimize the electricity charge exactly, optimization is sequentially performed in this paper, so-called the Two Stage Hybird optimization, where the extent to which the peak load savings is firstly accomplished through optimization of basic charge and then the optimization of energy charge is performed with different charge and discharge efficiency of ESS PCS. Finally, the proposed method is analyzed quantitatively with other optimization methods.

• Journal of Korean Society on Water Environment
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• v.22 no.5
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• pp.851-855
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• 2006

The aim of this study was to investigate characteristics of formation of mixed oxidants and some aspects of the performance of electrochemical process as an alternative disinfection strategy for water purification. The study of electrochemical process has shown free chlorine to be produced, but smaller amounts of stronger oxidants, such as ozone, hydrogen peroxide and OH radicals, were also generated. The formation of ozone and hydrogen peroxide increased with increasing electric conductivity, but was limited at conductivities greater than 0.6 mS/cm. Also, formation of OH radical was enhanced as electric conductivity was increased to 0.9 mS/cm and The stead-state concentrations of OH radical were calculated at $1.1{\sim}6.4{\times}10^{-14}M$. Using E. coti, inactivation kinetic studies were performed. With the exception of free chlorine, the role of mixed oxidants, especially OH radical, was investigated for enhancement of the inactivation rate.

• Korean Journal of Materials Research
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• v.32 no.11
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• pp.449-457
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• 2022

Halide perovskites are emerging materials for next-generation display applications, thanks to their narrow emission linewidth and band gap tunability, capable of covering the entire range of visible light. Despite their short period of research, perovskite light emitting diodes (PeLEDs) have shown rapid progress in device external quantum efficiency (EQE) in the near-infrared (NIR), red, and green emission wavelengths, and the record EQE has exceeded over 20 %. However there has been limited progress with blue emission compared to the red and green counterparts. In this review, the current status and challenges of blue PeLEDs are introduced, and strategies to produce spectrally stable blue PeLEDs are discussed. The strategies include 1) a mixed halide system in the form of 3-dimensional (3D) perovskites, 2) colloidal perovskite nanocrystals and 3) low dimensional perovskites, known as quasi-2D perovskites. In the mixed halide system, previous reports based on the compositional engineering of 3D perovskites to reduce spectral instability (i.e., halide segregation) will be discussed. Since spectral instability issue originate from the mixed halide composition in perovskites, the two other strategies are based on enlarging the band gap with a single halide composition. Finally, the prospects for each strategy are discussed, for further improvement in spectrally stable blue PeLEDs.

• Nuclear Engineering and Technology
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• v.56 no.6
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• pp.2428-2435
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• 2024

Training for radiation protection and control requires a visual understanding of radiation, which cannot be perceived by the human senses. Trainees must also master the effective use of measuring instruments. Traditionally, such training has exposed trainees to radiation sources. Here, we present a novel e-training strategy that enables safe, exposure-free handling of a radiation measuring tool called a survey meter. Our mixed reality radiation-training system merges the physical world with a digital one. Collaborating with a mixed reality headset (HoloLens 2), this system constructs a mock-up of a survey meter in real-world space. The HoloLens 2 employs a browser-based application to visualize radiation and to simulate/share the use of the survey meter, including its physical movements. To provide a dynamic learning experience, the system adjusts the survey-meter mock-up readings according to the operator's movements, distance from the radiation source, the response time of survey meter, and shielding levels. Through this approach, we expect that trainees will acquire practical skills in interpreting survey-meter readings and gain a visual understanding of radiation in real-world situations.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.27 no.1
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• pp.107-113
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• 2023

Mixed adenoneuroendocrine carcinoma is defined as a tumor with a mixture of adenocarcinoma components and neuroendocrine neoplasm components. Each of these two components of mixed adenoneuroendocrine carcinoma accounts for at least 30% of all tumors. Mixed adenoneuroendocrine carcinoma might be located in the ampulla of Vater, a very rare location compared to other organs. Thus, its treatment and prognosis plans have not been established yet. We report three cases of mixed adenoneuroendocrine carcinoma occurring in the ampulla of Vater. Each patient had a different clinical course. In general, difficulty in preoperative diagnosis, risk of early recurrence, and poor disease course were main hallmarks of mixed adenoneuroendocrine carcinoma arising from the ampulla of Vater. However, one patient in this case report survived although she did not receive adjuvant chemotherapy due to her old age. Therefore, it is important to establish a careful treatment strategy for mixed adenoneuroendocrine carcinoma arising from the ampulla of Vater.