• Industrial Engineering and Management Systems
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• 제16권1호
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• pp.118-128
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• 2017

Uncertain factors in finical markets make the prediction of future returns and risk of asset much difficult. In this paper, a model,assuming the admissible errors on expected returns and risks of assets, assisted in the multiperiod mean variance portfolio selection problem is built. The model considers transaction costs, upper bound on borrowing risk-free asset constraints, cardinality constraints and threshold constraints. Cardinality constraints limit the number of assets to be held in an efficient portfolio. At the same time, threshold constraints limit the amount of capital to be invested in each stock and prevent very small investments in any stock. Because of these limitations, the proposed model is a mix integer dynamic optimization problem with path dependence. The forward dynamic programming method is designed to obtain the optimal portfolio strategy. Finally, to evaluate the model, our result of a meaning example is compared to the terminal wealth under different constraints.

• 기술사
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• 제32권6호
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• pp.40-43
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• 1999

The R&D productivity has the same meaning as that of general meaning. Its input includes budget, facility, schedule, idea and target, and its output includes patent, paper, technological innovation and revenue increase and technology accumulation influenced by these factors. The choice of R&D item which will have the large effectiveness after customization, resource input of proper level, application of efficient development schema, effective usage of development output, objective appraisal for the R&D output and extension for the future project are the main factors for which is suggested to enhance the R&D productivity. The management's expectation for R&D can be represented as the innovativeness of output and potential influence to outsiders. The speedy output, even if incremental investment more than planning happens, will eventually result in the productivity enhancement of the enterprise, and managers must not encounter the opportunity loss in return for the excessive investment control.

• 조명전기설비학회논문지
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• 제20권9호
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• pp.40-44
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• 2006

This study investigated a new tuneable bandpass filter based on coplanar waveguide coupled line structure, and using the varactor diode for tuning the center frequency of the filter. The filter was designed by a commercial simulator and had a tuning range of 180[MHz] from 0.95[GHz] to 1.13[GHz]. The filter acceptable values regarding the insertion loss was less than 3[dB] and its return loss greater than 12[dB]. The figure of merit of the implemented tuneable filter increased with the reverse bias voltage up to 14[V] on the varactor diode. The proposed filter has a promising future as it can be used in integration processes and in various materials as substrate.

• Clinical and Experimental Pediatrics
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• 제58권2호
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• pp.47-51
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• 2015

Debriefing is a conversational session that revolves around the sharing and examining of information after a specific event has taken place. Debriefing may follow a simulated or actual experience and provides a forum for the learners to reflect on the experience and learn from their mistakes. Originating from the military and aviation industry, it is used on a daily basis to reflect and improve the performance in other high-risk industries. Expert debriefers may facilitate the reflection by asking open-ended questions to probe into the framework of the learners and apply lessons learned to future situations. Debriefing has been proven to improve clinical outcomes such as the return of spontaneous circulation after cardiac arrest and the teaching of teamwork and communication in pediatrics. Incorporating debriefing into clinical practice would facilitate the cultural change necessary to talk more openly about team performance and learn from near misses, errors, and successes that will improve not only clinical outcome but also patient safety.

• 한국IT서비스학회지
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• 제10권2호
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• pp.189-202
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• 2011

It is important issue how to evaluate the economic feasibility of computing factors in the real world when we build ubiquitous spaces. In this paper, we propose a simple model that can evaluate the economic feasibility of mobile RFID-based ubiquitous computing system which enables seamless communication between offline and online via embedded computing factors in the real world. To achieve this, we explore the meaning of mobile RFID system, the difference between our research and extant researches concerning the evaluation of economic feasibility in RFID system, and propose the so-called 'Tag-based Evaluation Model' (TEM) which is an evaluation model to access the economic feasibility of mobile RFID systems. We also analyze the TEM via simulation cases based on proposed model and discuss the future of TEM.

• Wind and Structures
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• 제8권4호
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• pp.269-281
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• 2005

The paper describes the work of the IAWE Working Group WGF - Extreme Wind Prediction and Zoning, one of the international codification working groups set up in 2000. The topics covered are: the international database of extreme winds, quality assurance and data quality, averaging times, return periods, probability distributions and fitting methods, mixed wind climates, directionality effects, the influence of orography, rare events and simulation methods, long-term climate change, and zoning and mapping. Recommendations are given to promote the future alignment of international codes and standards for wind loading.

• Molecules and Cells
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• 제41권3호
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• pp.161-167
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• 2018

Chloroplasts are present in organisms belonging to the kingdom Plantae. These organelles are thought to have originated from photosynthetic cyanobacteria through endosymbiosis. During endosymbiosis, most cyanobacterial genes were transferred to the host nucleus. Therefore, most chloroplast proteins became encoded in the nuclear genome and must return to the chloroplast after translation. The N-terminal cleavable transit peptide (TP) is necessary and sufficient for the import of nucleus-encoded interior chloroplast proteins. Over the past decade, extensive research on the TP has revealed many important characteristic features of TPs. These studies have also shed light on the question of how the many diverse TPs could have evolved to target specific proteins to the chloroplast. In this review, we summarize the characteristic features of TPs. We also highlight recent advances in our understanding of TP evolution and provide future perspectives about this important research area.

• Communications for Statistical Applications and Methods
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• 제16권4호
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• pp.647-658
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• 2009

It is already known from the previous study that flood seems to have heavier tail. Therefore, to make prediction of future extreme label, some agreement of tail behavior of extreme data is highly required. The LH-moments estimation method, the generalized form of L-moments is an useful method of characterizing the upper part of the distribution. LH-moments are based on linear combination of higher order statistics. In this study, we have formulated LH-moments of five distributions useful in hydrology such as, two types of three parameter kappa distributions, beta-${\kappa}$ distribution, beta-p distribution and a generalized Gumbel distribution. Using LH-moments reduces the undue influences that small sample may have on the estimation of large return period events.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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• pp.442-445
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• 2003

The use of a single UWB antenna which covers a wide range of frequencies is very desirable for future wireless communications system. In this paper, we propose a novel wide band printed elliptic monopole antenna for UWB(Ultra wide Band). Wideband planar monopole disc antenna have been recently studied. The proposed antenna can cover UWB frequencies from 3.5GHz to 12GHz. it is determined from 10dB return loss. The antenna consists of the printed elliptical monopole disc with microstrip-line feed. Elliptic disc of antenna and ground height operate important to matching. The results of measurement are almost similar to those of simulation.

• 유통과학연구
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• 제12권5호
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• pp.15-26
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• 2014

Purpose - This study addresses an acquisition's impact on a firm's strategic relationship based on findings of existing academic studies and theoretical assertions. Through examining existing research results and theoretical grounds for an acquisition's impact on various stakeholders, this study indirectly approaches the impact on stakeholders including alliance partners. Research design, data, and methodology - This research identified a variety of related theoretical foundations and empirical studies. Research objectives of prior studies mainly focused on merging firms and direct participants of acquisition activity. In addition, academic attention on the impact on rival firms has recently been growing. However, little research on alliance partners was found. Prior studies simultaneously employed event study methodology and cross-sectional analysis to make further theoretical contributions. Results and Conclusions - Based on the findings of prior studies, this research proposed a complementary research model for future academic inquiry into the impact of an acquisition on an alliance partner's return and for predicting an acquisition announcement's effect on alliance partners.