• Journal of the Korean Operations Research and Management Science Society
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• v.23 no.3
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• pp.135-151
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• 1998

The demand of large capacity in coming cellular systems makes inevitable the deployment of small cells, rendering more frequent handoff occurrences of calls than in the conventional system. The key issue is then how effectively to reduce the chance of unsuccessful handoffs, since the handoff failure is less desirable than that of a new call attempt. In this study, we consider the control policies which give priority to handoff calls by limiting channel assignment for the originating new calls, and allow queueing the new calls which are rejected at their first attempts. On this system. we propose the problem of finding an optimal call control strategy which optimizes the objective function value, while satisfying the requirements on the handoff/new call blocking probabilities and the new call delay. The objective function takes the most general form to include such well-known performance measures as the weighted average carried traffic and the handoff call blocking probability. The problem is formulated into two different linear programming (LP) models. One is based on the direct employment of steady state equations, and the other uses the theory of semi-Markov decision process. Two LP formulations are competitive each other, having its own strength in the numbers of variables and constraints. Extensive experiments are also conducted to show which call control strategy is optimal under various system environments having different objective functions and traffic patterns.

• Journal of the Korea Society of Computer and Information
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• v.20 no.7
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• pp.33-40
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• 2015

The time slot assignment problem (TSAP) or Satellite Communications scheduling problem (SCSP) for a satellite performs $n{\times}n$ ground station data traffic switching has been known NP-hard problem. This paper suggests $O(n^2)$ time complexity algorithm for TSAP of a satellite that performs $n^2{\times}n^2$ ground station data traffic switching. This problem is more difficult than $n{\times}n$ TSAP as NP-hard problem. Firstly, we compute the average traffic for n-transponder's basic coverage zone and applies ground station exchange method that swap the ground stations until all of the transponders have a average value as possible. Nextly, we transform the D matrix to $D_{LB}$ traffic matrix that sum of rows and columns all of transponders have LB. Finally, we select the maximum traffic of row and column in $D_{LB}$, then decide the duration of kth switch mode to minimum traffic from selected values. The proposed algorithm can be get the optimal solution for experimental data.

• Human Ecology Research
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• v.54 no.3
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• pp.239-250
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• 2016

This study identifies the aspects of a managers' perceived work experience in a Multicultural Family Support Center and analyzes how work experience backgrounds are formulated. In-depth interviews were conducted with 10 managers from March to September 2015 to understand managers' work experience. Descriptions from the interviews were analyzed using phenomenological research methods. The result show that their work experience can be categorized into 73 meanings, 10 subcategories, and five themes. The five themes are 'program development,' 'employees assignment optimization,' 'use and control network resources,' 'deal with changes in needs of multicultural families,' and 'supports vs. controls.' The analysis of the themes and subcategories from each theme allows us to first interpret that managers consider their significant and diversified work tasks overwhelming. Second, they find their jobs fit them and feel personally interested with a sense of duty from their work to overcome stress from heavy workloads. Third, managers put a high value on their work as a hands-on experience that is an officially authorized position from the government. Fourth, they are proud that they contribute to offering welfare services to multicultural families as members of Multicultural Family Support Centers.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.5
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• pp.2177-2193
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• 2018

This paper studies resource allocation schemes for the relay-aided cooperative system consisting of multiple source-destination pairs and decode-forward (DF) relays. Specially, relaying selection, multisubcarrier pairing and assignment, and power allocation are investigated jointly. We consider a combinatorial optimization problem on quality of experience (QoE) and energy consumption based on relay-aided cooperative system. For providing better QoE and lower energy consumption we formulate a multi-objective optimization problem to maximize the total mean opinion score (MOS) value and minimize the total power consumption. To this end, we employ the nondominated sorting genetic algorithm version II (NSGA-II) and obtain sets of Pareto optimal solutions. Specially, two formulas are devised for the optimal solutions of the multi-objective optimization problems with and without a service priority constraint. Moreover, simulation results show that the proposed schemes are superior to the existing ones.

• Journal of Korea Multimedia Society
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• v.10 no.5
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• pp.687-697
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• 2007

Although the Java bytecode has numerous advantages, there are also shortcomings such as slow execution speed and difficulty in analysis. Therefore, in order for the Java class file to be effectively executed under the execution environment such as the network, it is necessary to convert it into optimized code. We implemented CTOC for transforming to optimized code. In Optimization, SSA Form that distinguish variable by assignment is used to determine value and type statically. Copy propagation, dead code elimination optimization is applied to SSA Form. However, existing SSA Form is related to variable than expression. Therefore, in this paper, to performing optimization to SSA Form expression, after performing copy propagation and dead code elimination, in addition to that, partial redundant expression elimination is performed

• Journal of Korean Academy of Nursing
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• v.50 no.6
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• pp.787-798
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• 2020

Purpose: This study aimed to assign weights for subscales and items of the Post-Intensive Care Syndrome questionnaire and suggest optimal cut-off values for screening unplanned hospital readmissions of critical care survivors. Methods: Seventeen experts participated in an analytic hierarchy process for weight assignment. Participants for cut-off analysis were 240 survivors who had been admitted to intensive care units for more than 48 hours in three cities in Korea. We assessed participants using the 18-item Post-Intensive Care Syndrome questionnaire, generated receiver operating characteristic curves, and analysed cut-off values for unplanned readmission based on sensitivity, specificity, and positive likelihood ratios. Results: Cognitive, physical, and mental subscale weights were 1.13, 0.95, and 0.92, respectively. Incidence of unplanned readmission was 25.4%. Optimal cut-off values were 23.00 for raw scores and 23.73 for weighted scores (total score 54.00), with an area of under the curve (AUC) of .933 and .929, respectively. There was no significant difference in accuracy for original and weighted scores. Conclusion: The optimal cut-off value accuracy is excellent for screening of unplanned readmissions. We recommend that nurses use the Post-Intensive Care Syndrome Questionnaire to screen for readmission risk or evaluating relevant interventions for critical care survivors.

• Journal of English Language & Literature
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• v.64 no.3
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• pp.329-345
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• 2018

Sun Yung Shin's poetry collection Skirt Full of Black (2007) brings the author's personal history as a Korean female adoptee to bear upon poetic language in daring formal experiments, instantiating the liminal state of being shuttled across borders to land in an in-between state of marginalization. Other Korean American poets have also drawn on the experience of transnational adoption and racialization explore the literary potential of English to materialize haunting memories or the untranslatable yet persistent echoes of a lost home that gestures across linguistic boundaries, as seen in the case of Lee Herrick or Jennifer Kwon Dobbs. Shin however dismantles the referential foundation of English as a language she was transplanted into through formal transgressions such as frazzled syntax, atypical typography, decontextualized punctuation marks, and phonetic and visual play. The power to signify and thereby differentiate one entity or meaning from another dissipates in the cacophonic feast of signs in Skirt Full of Black; the word fragments of identificatory markers that turn racialized, gendered, and culturally contained subjects into exotic things lose the power to define them as such, and instead become alterities by departing from the conventional meaning-making dynamics of language. Expanding on the avant-garde legacy of Korean American poets Theresa Hak Kyung Cha and Myung Mi Kim to delve further into the liminal space between Korean and American, referential and representational, or spoken and written words, Shin carves out a space for discreteness that does not subscribe to the hierarchical ontology of differential value assignment.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.2
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• pp.93-102
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• 2022

The goal of this study was to see how big data analytics (BDA) affected external audit procedures in the Middle East. The measurement model and structural model of this investigation were evaluated using PLS-SEM (3.3.3). The study sample members were (361) auditors who work in auditing companies in Kuwait, Saudi Arabia, the United Arab Emirates, Jordan, Bahrain, Egypt, Lebanon, and Iraq. A questionnaire was chosen to the study sample members electronically, and the study sample members were (5093) auditors who work in auditing companies in Kuwait, Saudi Arabia, the United Arab Emirates, Jordan, Bahrain, Egypt, Lebanon, and Iraq. To choose the sample, the researchers used a stratified random sampling procedure. The findings show that BDA has an impact on audit procedures at all phases of the auditing process, where it contributes to information delivery that helps auditors understand the client's internal and external environments, which in turn influences the choice to accept the audit assignment. Furthermore, by providing essential information, BDA enables auditors to simply run analytical procedures, estimate client risks, and understand and evaluate the internal control system. As a result, auditors must develop their abilities in the BDA field, as it adds to the creation of additional value for both auditors and their clients.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.7
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• pp.946-951
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• 2003

The Genetic diversity and relationship of native Siri (Bos indicus) cattle populations of Bhutan were evaluated using 20 microsatellite markers. A total of 120 Siri cattle were sampled and were grouped into four populations according to their geographical locations which were named Siri West, Siri South, Siri Central and Siri East cattle. For each, 30 individuals were sampled. In addition, 30 samples each of Indian Jaba (B. indicus), Tibetan Goleng (B. taurus), Nepal Hill cattle (B. indicus), Holstein Friesian (B.taurus) and Mithun (B. frontalis) were typed. The mean number of alleles per loci (MNA) and observed heterozygosity (Ho) were high in the Siri populations ($MNA=7.2{\pm}0.3$ to $8.9{\pm}0.5$ and $Ho=0.67{\pm}0.04$ to $0.73{\pm}0.03$). The smallest coefficient of genetic differentiation and genetic distance ($F_{ST}=0.015$ and $D_A=0.073$) were obtained between Siri West and Siri Central populations. Siri East population is genetically distinct from the other Siri populations being close to the Indian Jaba ($F_{ST}=0.024$ and $D_A=0.084$). A high bootstrap value of 96% supported the close relationship of Siri South, Siri Central and Siri West, while the relationship between Siri East and Jaba was also supported by a high bootstrap value (82%). Data from principal component analysis and individual assignment test were in concordance with the inference from genetic distance and differentiation. In conclusion we identified two separate Siri cattle populations in Bhutan at the genetic level. One population included Siri cattle sampled from the West, Central and South of the country and the other Siri cattle was sampled from the East of the country. We suggest that Siri cattle conservation program in Bhutan should focus on the former population as it has received less genetic influence from other cattle breeds.

• Journal of Intelligence and Information Systems
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• v.15 no.1
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• pp.1-14
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• 2009

The Capacitated Vehicle Routing Problem (CVRP) is the problem that the vehicles stationed at central depot are to be optimally routed to supply customers with demands, satisfying vehicle capacity constraints. The CVRP is the NP-hard as it is a natural generalization of the Traveling Salesman Problem (TSP). In this article, we propose the heuristic algorithm, called the bisection seed detection method, to solve the CVRP. The algorithm is composed of 3-phases. In the first phase, we work out the initial cluster using the improved sweep algorithm. In the next phase, we choose a seed node in each initial cluster by using the bisection seed detection method, and we compose the rout with the nearest node from each seed. At this phase, we compute the regret value to decide the list of priorities for the node assignment. In the final phase, we improve the route result by using the tabu search and exchange algorithm. We compared our heuristic with different heuristics such as the Clark-Wright heuristic and the genetic algorithm. The result of proposed heuristic show that our algorithm can get the nearest optimal value within the shortest execution time comparatively.