• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.3
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• pp.324-340
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• 2010

Video streaming service over wireless networks is a challenging task because of the changes in the wireless channel conditions that can occur due to interference, fading, and station mobility. To provide an efficient wireless video streaming service, the rate adaptation scheme should improve wireless node performance and channel utilization. Moreover, the quality adaptation scheme should be considered at the streaming application. To meet these requirements, we propose a new cross-layer design for video streaming over wireless networks. This design includes the rate and quality adaptation schemes. The rate adaptation scheme selects the optimal transmission mode and resolves the performance anomaly problem. Based on performance improvement by the proposed rate adaptation scheme, our quality adaptation scheme improves the quality of video streaming. Through performance evaluations, we prove that our cross-layer design improves the wireless channel utilization and the quality of video streaming.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.283-284
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• 2008

A cross-layer optimization is becoming a popular design methodology for the IP based next generation wireless network. We begin by investigating a cross-layer optimization scheme to enhance the system performance in wireless networks. By applying cross-layer optimization methodology to WiBro distributed network, the WiBro systems are expected to gain significant performance improvement and resource utilization enhanced. For further study we highlight some open challenges and new opportunities for cross-layer design.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.271-275
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• 2015

A variety of evaluation application and initiatives on the adoption of Building Information Modelling (BIM) have been introduced in recent years. Most of which however, focused mainly on evaluating design to construction phase-processes, or BIM utilization performances. Through studying existing publications, it is found that continuous utilization of BIM data throughout the building's life cycle is comparatively less explored or documented. Therefore, this study looks at improving this incomplete life cycle condition with the concept that accumulated BIM data should be carried forward and statistically quantified for cross comparison, in order to facilitate practitioners to better improve the projects the future. Based on this conceptual theory of moving towards a closedloop BIM building life cycle, this study explores, through existing literature, the use of cloud based computing as the means to quantify and adaptively utilize BIM data. Categorization of BIM data relations in adaptive utilization of BIM data is then suggested as a initial step for enhancing cross comparison of BIM data in a cloud environment.

• Korea Trade Review
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• v.45 no.5
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• pp.181-200
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• 2020

The Korea-Canada FTA and the EVTA have adopted cross-cumulation clauses in their rules of origin, aiming at the enhancement of the value chains among the FTA parties. In fact, intricate rules of origin are often considered as the major cause that discourages the utilization of the agreement for the exporting firms. From this perspective, the correct understanding of cross-cumulation clauses in FTAs is an urgent mission for the Korean exporters as well, and the EVTA, which has recently introduced the cross-cumulation method in a linkage with the Korea-EU FTA provides the timely motivation. This paper first analyzes the Korea-Canada FTA of 2015 as for the case study, because this is a unique trade agreement for Korea that has already adopted the cross-cumulation clauses. It is concluded that the clause is rather vague, particularly in certifying the origins of the intermediate goods from the territory of an authorized third party. From this perspective, the recently-ratified EVTA is particularly important and meaningful with its clearer explanations for the utilization of the privileged rules of origin. The paper finalizes the study by making policy suggestions to the stakeholders, expecting more future FTAs to come equipped with similar cumulative rules of origin, and implies the possibility of the modification of the current clauses in the FTA with Canada.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.6
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• pp.543-550
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• 2003

In order to saving the energy for HVAC system of buildings, utilization of wind-induced cross ventilation is thought to be promising. However, utilization of natural ventilation alone is not sufficient for maintaining the human thermal-comfort such as in hot and humid regions. A hybrid air conditioning system with a controlled natural ventilation system, or combination of natural ventilation with mechanical air conditioning is thought to overcome the deficiency of wind-driven cross ventilation and to have significant effects on energy reduction. This paper describes a concept of hybrid system and propose a new type of hybrid system using radiational cooling with wind-induced cross ventilation. Moreover, a radiational cooling system is compared with an all-air cooling system. The characteristics of the indoor environment will be examined through CFD (Computational Fluid Dynamics) simulation, which is coupled with a radiation heat transfer simulation and with HVAC control in which the PMV value for the human model in the center of the room is controlled to attain the target value.

• Health Policy and Management
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• v.1 no.1
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• pp.116-135
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• 1991

Few studies have been conducted on the detailed routes of medical care utilization under the National Health Insurance. This study was undertaken to identify the utilization patte군 of health care facilities among industrial workers and their dependents. One of the largest health insurance association was purposively chosen for this objective. The association had 345, 757 members as of 31 December, 1990. The study sample of 297, 948 subjects have been drawn from the membership pool on the basis of their continuous membership status during 1 January through 31 December 1990. This study has tried to identify differential utilization patterns between acute and chronic conditions, and among standard income classes. All the diagnoses were recoded in a manner to achieve the objective of this study. As for acute diseases, most age group had used one medical facility as much as by 60% except the age group of 1-4, This young age group had used over three different health facilities as much as by 10.9-15.8%. The finding suggests that some policy measures by sought for remedying the excessive/inappropriate use of services. In addition, mid-income classes(between 17 and 48) were more likely to use multiple sources of care than lower income classes(between 1 and 16) and upper income classes(above 49). This study has revealed that chronic cases are more likely to pursue multiple sources of care, however those with chronic conditions tend to use single health facility more than those with acute conditions(67.9% versus 52.4%). As many as 12.2% have visited more than three health facilities in chronic conditions, but 5.9% for acute conditions. The most likely source of care was primary clinics for both acute and chronic conditions. Compared with the role of general hospital, small-size hospitals found to play a minimal role in the care and referral of patients. This indicates the need of strengthening the function of small-size hospitals. While a minor cross utilization of western medicine and pharmacy was noted, no significant boundary crossing was identified between western medicine and oriental medicine, or between pharmacy and oriental medicine. It is too early to confirm that whether there is substitutability or cross utilization among these alternative sources of care. A further study is needed to identify these relationship.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.12
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• pp.3071-3095
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• 2013

Configuring optimization of wireless sensor networks, which can improve the network performance such as utilization efficiency and network lifetime with minimal energy, has received considerable attention in recent years. In this paper, a cross layer optimal approach is proposed for multi-source linear network and grid network under Rayleigh block-fading channels, which not only achieves an optimal utility but also guarantees the end-to-end reliability. Specifically, in this paper, we first strictly present the optimization method for optimal nodal number $N^*$, nodal placement $d^*$ and nodal transmission structure $p^*$ under constraints of minimum total energy consumption and minimum unit data transmitting energy consumption. Then, based on the facts that nodal energy consumption is higher for those nodes near the sink and those nodes far from the sink may have remaining energy, a cross layer optimal design is proposed to achieve balanced network energy consumption. The design adopts lower reliability requirement and shorter transmission distance for nodes near the sink, and adopts higher reliability requirement and farther transmission distance for nodes far from the sink, the solvability conditions is given as well. In the end, both the theoretical analysis and experimental results for performance evaluation show that the optimal design indeed can improve the network lifetime by 20-50%, network utility by 20% and guarantee desire level of reliability.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.2
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• pp.103-114
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• 1989

Reciprocal crosses were conducted between three strains of Taiwan Country chickens, developed in the National Chung-Hsing University, and two strains of Single Comb White Leghorns, developed in the Taiwan Livestock Research Institute. Traits studied were growing performances, laying performances, egg quality traits and traits concerning disease resistance, including resistance to Marek's disease virus and immune responses to Newcastle disease virus vaccine and to sheep red blood cell. Results indicated that laying performances of Taiwan country chickens were much inferior to White Leghorns, but they matured earlier, their eggs had better shell strength and larger proportion of yolk, and their general disease resistance was much better than White Leghorns. Heterosis were found in laying performances and egg quality traits. The heterosis in laying traits was so large that the hybrid laid as many eggs and as large eggs as did pure strains of White Leghorns. Strategies on the improvement of native chickens and the utilization of genetic merits of native chickens were also discussed.

• Journal of the Optical Society of Korea
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• v.17 no.5
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• pp.371-375
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• 2013

To improve the utilization efficiency of solar energy, a new solar optical concentrating system composed of a parabolic reflector with a square cross-section, a hyperbolic reflector with a square cross-section and two converging convex lenses has been designed. The proposed method can simultaneously focus and shape sun light into a square pattern on the solar panel. In addition, the total reflection property of photonic crystal within the range of the visible sunlight spectrum has been analyzed. Finally, the relationship between solar concentrating multiples and the diameter of the primary mirror has been discussed.

• Child Health Nursing Research
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• v.29 no.4
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• pp.252-259
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• 2023

Purpose: Falls are a common cause of unintentional injuries in infants. This study was conducted to examine the patterns of healthcare utilization following infant falls in South Korea. Methods: This cross-sectional descriptive study utilized an online survey designed to gather information regarding the general characteristics of parents and infants, fall-related variables, and healthcare use. Results: The most serious falls identified by parents occurred at an average infant age of 6.97 months. Most fall incidents took place indoors (95.7%), and many occurred under the supervision of caregivers (68.0%). Following the fall, 36.4% of the participants used healthcare services. Logistic regression analysis revealed that healthcare use following an infant fall was significantly associated with being a firstborn child (odds ratio [OR]=5.32, 95% confidence interval [CI], 2.19-15.28) and falling from a caregiver's arms (OR=4.22; 95% CI, 1.45-13.68). Conclusion: To prevent and decrease the frequency of infant falls, improvements are needed in both the domestic environment and parenting approaches.