• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.7
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• pp.1831-1853
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• 2012

By sending periodically short bursts of traffic to reduce legit transmission control protocol (TCP) traffic, the low-rate denial of service (LDoS) attacks are hard to be detected and may endanger covertly a network for a long period. Traditionally, LDoS detecting methods mainly concentrate on the attack stream with feature matching, and only a limited number of attack patterns can be detected off-line with high cost. Recent researches divert focus from the attack stream to the traffic anomalies induced by LDoS attacks, which can detect more kinds of attacks with higher efficiency. However, the limited number of abnormal characteristics and the inadequacy of judgment rules may cause wrong decision in some particular situations. In this paper, we address the problem of detecting LDoS attacks and present a scheme based on the fluctuant features of legit TCP and acknowledgment (ACK) traffic. In the scheme, we define judgment criteria which used to identify LDoS attacks in real time at an optimal detection cost. We evaluate the performance of our strategy in real-world network topologies. Simulations results clearly demonstrate the superiority of the method proposed in detecting LDoS attacks.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.835-839
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• 2013

In this paper, We operate at a relatively low BER or using forward error control coding techniques on ways to increase the capacity of optical communication systems research. Coding gain is defined as the ratio of the probability of the coded signal and coding of error signal. Coding gain is increased, partly because of the period, to reduce the value of the optimal coding of the signal error probability decreases because of the effective bit binary symbol duration is longer than can be ignored. Transmission capacity on the coding gain for various code rates, which show the extent of up to 75Gb/s transmission capacity to get through it was confirmed that these coding techniques.

• Archives of Plastic Surgery
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• v.35 no.5
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• pp.545-552
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• 2008

Purpose: The transaxillary approach for breast augmentation has been advocated for patients and surgeons for several decades. However, this blind technique had many disadvantages including, traumatic dissection, difficult hemostasis, displacement of implants, and ill-defined asymmetrical location of inframammary crease. In the present study, the precise endoscopic electrocautery dissection was applied to eliminate the limits of blunt dissection throughout the procedures. Methods: From December 2006 to December 2007, a total of 103 patients with an average age of 29.5 years underwent endoscopic assisted transaxillary dual plane augmentation mammoplasty. The mean implant size was 243 cc with the range between 150 and 350 cc. Through a 4 cm axillary incision, electrocautery dissection for submuscular pockets was carried out under the endoscopic control. The costal origin of pectoralis muscle was completely divided to expose subcutaneous tissue and to make type I dual plane. Results: Using the endoscopic dissection, we achieved good aesthetic results including a short recovery period, less morbidity, and symmetrical well-defined inframammary crease. Type I dual plane procedure could support the consistent inframammary fold shape and be applied to most patients without breast ptosis. Minor complications did not occur, however, four major complications of capsular contracture occurred. Conclusion: In contrast to the era of the blind techniques, endoscopic assisted transaxillary dual plane breast augmentation can now be performed effectively and reproducibly. With Its advantage, the axillary application of endoscopy for augmentation mammaplasty is useful to achieve the optimal cosmetic outcomes.

• The Journal of Korean Society for Radiation Therapy
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• v.9 no.1
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• pp.50-55
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• 1997

The optimal management of uveal melanoma is still a matter of controversy. To determine the effect of Gamma Knife surgery for patients with uveal malanoma. the authors reviewed the results of 5 patients underwent Gamma Knife sugery between Sep. 1993 and Dec. 1996. The mean age was 60.7 years ranging from 42.5 to 76.5 years. Median follow-up was 13.29 months and the patient with follow up period more than 6 months was 4. The mean tumor volume was $3442 mm^3$(mean diameter 15.3 mm) and all patients were irradiated with a mean maximum dose of 74Gy(range $60\~80\;Gy$), using the $50\%$ isodose. After Gamma Knife surgery. one pateint showed complete disapperance in tumor size with follow-up 32 months, one enucleation due to progression, and 2 no interval change. In regard to vision, one patient blind. one enucleation, and 2 patients had no interval change. According to our experiences, Gamma Knife surgery for uveal melanoma be able to achieve local tumor control, spare the eyeball, and have possibility of save vision.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.302-307
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• 2001

This research is concerned with the development of a real-time adaptive PPF controller for the active vibration suppression of smart structure. In general, the tuning of the PPF controller is carried out off-line. In this research, the real-time learning algorithm is developed to find the optimal filter frequency of the PPF controller in real time and the efficacy of the algorithm is proved by implementing it in real time. To this end, the adaptive algorithm is developed by applying the gradient descent method to the predefined performance index, which is similar to the method used popularly in the optimization and neural network controller design. The experiment was carried out to verify the validity of the adaptive PPF controller developed in this research. The experimental results showed that adaptive PPF controller is effective for active vibration control of the structure which is excited by either impact or harmonic disturbance. The filter frequency of the PPF controller can be tuned in a very short period of time thus proving the efficiency of the adaptive PPF controller.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.369-370
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• 2002

A fungus. Penicillium sp. PS-113, with high phosphate-solubilizing activities was isolated from soil and formulated to powder type in order to manufacture it as a solid powder fertilizer. First of all, in this research, we are trying to establish an optimal condition for a drying process based on the drying time, temperature and humidity by testing its viability on potato dextrose agar(PDA) media after storing at $4^{\circ}C$. As a result the number of Penicillium sp. PS-1l3 conidia, which was dried at $80^{\circ}C$ and 15% humidity, and then stored at $4^{\circ}C$, was maximally increased to 60 times more than the control. But the viability of the conidia at $100^{\circ}C$ or over was decreased suddenly in spite of the period of storage.

• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1364-1368
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• 2009

Lysosomes, as a cell organelle type, are safe biological control agents that may be possible replacements for chemical antimicrobial agents because they are simply isolated from egg white. In this study, it was found that the lysosomes isolated from egg white exhibited pH-dependent antimicrobial activity, with the optimal activity found at pH 6.0. The efficiency of lysosomes in inhibiting bacterial growth and activity was evaluated over a 12-h treatment period. Seven different microorganisms were used as bacterial strains, and the lysosomes showed a significant antimicrobial effect against all strains. In addition, the antimicrobial activity was maintained for 100 days, and there did not appear to be any resistance of E. coli to the lysosomal activity up to the eighth culture. However, the lysosomes did not affect the viability of mammalian cells, suggesting the biocompatibility of lysosomes. These highly effective lysosomes have a bright future in the application of novel antimicrobial sources as a cell organelle type.

• The Korean Journal of Food And Nutrition
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• v.7 no.3
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• pp.169-176
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• 1994

Screening was performed on edible natural sources to examine superoxide radical scavenging activities by using the method of superoxide dismutase assay. Among 47 kinds of samples, the extract of Capsella bursa-pastoris showed a potent superoxide radical scavenging activity of 11.6 unit / mg solid and was selected for further studies. In order to select optimal extraction solvent system, Cappella bursa-pastoris was extracted with various solvents and the electron donating abilities and inhibitory effects on lipid peroxidation of linoleic acid were measured. Among them, the ethanol extract of Capsella bursa-pastoris possessed the highest level of activities. The ethanol extract of Cappella bursa-pastoris was found to have an inhibitory effect on autoxidation of soybean oil at 5$0^{\circ}C$ from peroxide value, conjugated diene value and refractive index. In the soybean oil containing 0.2% of ethanol extract, induction period was increased 2 times in comparison with control.

• Journal of the Korea Institute of Building Construction
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• v.4 no.1
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• pp.105-110
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• 2004

Resource procurement is an important management area because cost of resource covers 40％ of total construction project cost and resource delivery has direct relationship with project performance. Integration of cost provides various potentials for effective and efficient project control. This study investigates the usefulness of time in resource procurement management focused on materials. These days, construction projects have characterized manufacture because of industrialization and component. Therefore, application of systematic resource planning has been requested in the construction. There are many companies conducting procurement of resource on the web by applying MRP, ERP etc. in the construction. However, in applying them in the construction yet, there is obstruction. MRP has the character doing its function under accurate cost prediction of resource. But prediction of resource is difficult in industry mechanism of the construction. If accurate cost prediction of resource is possible in the construction, it will be expected to reduce cost of procurement of resource substantially by applying successful resource planning model in the manufacture. On the basis of recent current, the purpose of study is to present procurement of resource system that period observance of construction and minimization of stock is possible by reflecting accurate lead-time to apply proactive thought to be able to cope with alteration of construction schedule efficiently in analyzing resource planning of the construction site.

• Food Science and Biotechnology
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• v.14 no.3
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• pp.358-362
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• 2005

Eudragit E100 microcapsules containing nisin were prepared and employed to control the ripening of kimchi. The recovery yields of microcapsules without/with nisin ranged from 93.53 to 94.61 % and 92.85 to 94.09 %, respectively. The particle size of microcapsules decreased (>200 to $100\;{\mu}m$) as the amount of aluminium tristearate increased from 6.0 to 15 %. The microcapsules were morphologically spherical and possessed rough surface. Nisin was completely released from the microcapsules within a day at pH 3.0 and within two days at pH 4.0, 5.0, and 6.0, respectively, whereas half the amount of nisin was released at pH 7.0 within two days. During fermentation of kimchi with microcapsules containing nisin, the pH decrease was retarded which resulted in a constant pH of approximately 4.2. The pH of 4.2 was optimal for ripening of kimchi for a longer period of time when compared with samples without nisin.