• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권9호
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• pp.3594-3610
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• 2015

Recent advancements in broadband wireless communication technologies enable mobile users to receive video streaming services with various smart devices. The long term evolution (LTE) network provides high bandwidth and low latency for several emerging mobile applications. This paper proposes the buffer aware scheduling (BAS) approach to schedule the downlink video traffic in LTE network. The proposed BAS scheme applies the weighting function to heuristically adjust the scheduling priority by considering the buffer status and channel condition of UE so as to reduce the time that UE stays in the connected state without receiving data. Both of 1080P and 2160P resolution video streaming sources were applied for exhaustive simulations to examine the performance of the proposed scheme by comparing to that of the fair bandwidth (FB) and the best channel quality indicator (CQI) schemes. The simulation results indicate that the proposed BAS scheme not only achieves better performance in power saving, streaming delivery time, and throughput than the FB scheme while maintaining the similar performance as the best CQI scheme in light traffic load. Specifically, the proposed scheme reduces streaming delivery time and generates less signaling overhead than the best CQI scheme when the traffic load is heavy.

• Journal of Biosystems Engineering
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• 제38권2호
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• pp.149-162
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• 2013

Purpose: In image segmentation via thresholding, Otsu and Kapur methods have been widely used because of their effectiveness and robustness. However, computational complexity of these methods grows exponentially as the number of thresholds increases due to the exhaustive search characteristics. Methods: Particle swarm optimization (PSO) and genetic algorithms (GAs) can accelerate the computation. Both methods, however, also have some drawbacks including slow convergence and ease of being trapped in a local optimum instead of a global optimum. To overcome these difficulties, we proposed two new multi-level thresholding methods based on Bacteria Foraging PSO (BFPSO) and real-coded GA algorithms for fast segmentation. Results: The results from BFPSO and real-coded GA methods were compared with each other and also compared with the results obtained from the Otsu and Kapur methods. Conclusions: The proposed methods were computationally efficient and showed the excellent accuracy and stability. Results of the proposed methods were demonstrated using four real images.

• 지역연구
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• 제11권1호
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• pp.31-60
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• 1995

The distribution of economic activity over a mutually exclusive and exhaustive categorical industry-region matrix is modeled as a composition of two random components: the probability-like share distribution of jobs and the dynamic evolution of absolute aggregates. The former describes the individual activity location choice by comparing the predicted profitability of the current industry-region pair against that of all other alternatives based on the available information on industry-specific, region specific, or activity specific attributes. The latter describes the time evolution of macro-level aggregates using a dynamic reduced from model. With the seperation of micro choice behavior and macro dynamic aggregate constraint, the usual independence and identicality assumptions become consistent with the activity share distribution, hence multi-regional industrial migration can be represented by a set of probability evolution equations in a conservative Markovian from. We call this a Micro-Macro Composition Approach since the product of the aggregate prediction and the predicted activity share distribution gives the predicted activity distribution gives the predicted activity distribution which explicitly considers the underlying individual choice behavior. The model can be applied to interesting practical problems such as the plant location choice of multinational enterprise, the government industrial ploicy to attract international firms, and the optimal tax-transfer mix to influence activity location choice. We consider the latter as an example.

• 공학교육연구
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• 제16권5호
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• pp.24-35
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• 2013

This study aims to explore self-directed learning strategies of high academic achievers majoring in engineering. The research participants were 21 fourth-year students who had attained the first or second highest cumulative grade point average in each department during the past three-year and were asked to write an essay on "my successful learning methods or techniques." The essays were analyzed by theme analysis method which is one of the qualitative methods to extract the self-directed learning strategies used by high performing students. According to the results of this study, the self-directed learning strategies of excellent students could be categorized into fundamental strategies to induce self-directed learning, preparatory strategies, implementation strategies and management strategies for marinating self-directed learning. Detail information on each category is as follow: 1) fundamental strategies refer to positive and pleasant mind, academic confidence and effort attribution, 2) preparatory strategies refer to concrete and challenging goal setting, establishment of learning strategies adjusted courses characteristics and practical learning planning, 3) implementation strategies refer to intensive learning in class, knowledge exploration, knowledge acquisition, social networking and exhaustive preparation for exams and 4) management strategies refer to time management and learning environment management.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권5호
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• pp.1920-1937
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• 2015

Network environment has been under constant threat from both malicious attackers and inherent vulnerabilities of network infrastructure. Existence of such threats calls for exhaustive vulnerability analyzing to guarantee a secure system. However, due to the diversity of security hazards, analysts have to select from massive alternative hardening strategies, which is laborious and time-consuming. In this paper, we develop an approach to seek for possible hardening strategies and prioritize them to help security analysts to handle the optimal ones. In particular, we apply a Risk Flow Attack Graph (RFAG) to represent network situation and attack scenarios, and analyze them to measure network risk. We also employ a multi-objective genetic algorithm to infer the priority of hardening strategies automatically. Finally, we present some numerical results to show the performance of prioritizing strategies by network risk and hardening cost and illustrate the application of optimal hardening strategy set in typical cases. Our novel approach provides a promising new direction for network and vulnerability analysis to take proper precautions to reduce network risk.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권11호
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• pp.5264-5281
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• 2017

Multihop relay-based cellular networks are attracting much interest because of their throughput enhancement, coverage extension, and low infrastructure cost. In these networks, relay stations (RSs) between a base station (BS) and mobile stations (MSs) drastically increase the overall spectral efficiency, with improved channel quality for MSs located at the cell edge or in shadow areas, and enhanced throughput of MSs in hot spots. These relay-based networks require an advanced radio resource management scheme because the optimal amount of radio resource for a BS-to-RS link should be allocated according to the MS channel quality and distribution, considering the interference among RSs and neighbor BSs. In this paper, we propose optimal resource planning algorithms that maximize the overall utility of relay-based networks under a proportional fair scheduling policy. In the first phase, we determine an optimal scheduling policy for distributing BS-to-RS link resources to RSs. In the second phase, we determine the optimal amount of the BS-to-RS link resources using the results of the first phase. The proposed algorithms efficiently calculate the optimal amount of resource without exhaustive searches, and their accuracy is verified by comparison with simulation results, in which the algorithms show a perfect match with simulations.

• Journal of Periodontal and Implant Science
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• 제32권4호
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• pp.745-752
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• 2002

Osteomyelitis is an exhaustive disease whose main feature is an inflammation of inner part of bone, bone marrow. In oral and maxillofacial area, we have maxillary and mandibular osteomyelitis and the latter is dominant because of its impaired blood supply. The main cause of osteomyelitis is a bacterial infection and the ways of infections are by periapical odontogenic infection, fracture, post-operative complication, and periodontal disease. The predominant etiologic factor is periapical odontogenic infection mostly caused by advanced dental caries. It is generally believed that periodontal disease could be a cause of osteomyelitis. But periodontal disease is usually confined to the alveolar bone area and not extends to the underlying bone marrow. Accordingly periodontal infection per se rarely cause produce oseomyelitis. Even though osteomyeltis could be occurred by periodontal disease, its virulence of infection is milder than periapical odontogenic infection. So it usually provokes sclerosing or hyperplastic osteomyelitis rather than suppurative type. We had a case of suppurative osteomyelitis caused by periodontal disease and treated it with periodontal and oral and maxillofacial surgical method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.988-989
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• 2006

The ultrasonic welding is with features of high electric conductivity and hot conductivity when it is used in metallic bond, high electric conductivity and hot conductivity when it is used in various metallic bonds, excellent quality when it is used for advanced junction, easiness when it is used in various metallic bonds, being needless for the exhaustive material and being benefit for the environment. Currently the use of ultrasonic welding is increasing in the industrial fields such as the automobile battle, the refrigerator, the air conditioner, the battery and the solar cell junction. But the production ability is insufficient in our country and it is necessary to explore the core technology of the ultrasonic welding. In this paper, the output LC resonance filter and 35kHz squal wave onion occurrence Full Bridge plans was designed. The output examination of the ultrasonic oscillator and the ultrasonic welding examination were done. The method for getting more smooth result in the ultrasonic welding machine system was researched.

• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.383-391
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• 2014

Biotin-S-S-Phosphine was designed and synthesized as a potential tool for a proteomic study of O-GlcNAcmodified proteins. This reagent features a disulfide linker between a triarylphosphine moiety, which allows selective conjugation to azide-containing proteins, and a biotin moiety that can allow easy isolation through its strong affinity toward avidin-coated solid beads. The disulfide linkage within this reagent can allow the easy release of the bound molecules of interest, which is difficult to achieve when a biotin:avidin pair is used alone, by reducing the disulfide bond of the reagent with DTT. Preliminary in vitro biological assays with azidelabeled and unlabeled cell lysates and a pure protein Nup62 showed that the Biotin-S-S-Phosphine reagent is highly reactive toward the free thiol groups of proteins. When a molecular tool with a disulfide linker is applied to the enrichment of the molecules of interest from other species, it is important to block the free-thiols of the sample using exhaustive alkylation prior to the Staudinger ligation reactions to restore the bioorthogonal nature of this reaction.

• 한국식품영양과학회지
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• 제27권6호
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• pp.1105-1109
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• 1998

The superoxide dismutase(SOD) in peeled pericarp of cucumber was most stable at pH 8.0 and relatively stabe between pH 5.0 and 9.0. The enzyme was stable up to 6$0^{\circ}C$ and retained 12% by heat treatment at 10$0^{\circ}C$ for 5 min. At pH 2.0, the peeled pericarp enzyme activity was decreased to 10% by incubation for 3 hrs. However, the enzyme activity was increased above 25% after incubating the enzyme at pH 7.0 for 6 hrs. Retention of SOD activity in cucumber by various heating methods was also measured. The residual SOD activities of peeled pericarp and whole cucumber was estimated to be 25% and 27% after blanching(2 min), respectively. The skin enzyme retained 53% of its activity after steaming (3 min). When the peeled pericarp enzyme was incubated at 4$^{\circ}C$ for 20 days, the enzyme activity remained about 81%. However, when the enzyme incubated at 3$0^{\circ}C$ for 20 days, the peeled pericarp enzyme activity decreased to 17% of its original activity. The enzyme activity of peeled pericarp cucumber was not changed after exhaustive dialysis for 3 days, which indicated that the SOD activity in cucumber seems to have molecular weight above 12,000.