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A Study of the Intelligent Connection of Intrusion prevention System against Hacker Attack (해커의 공격에 대한 지능적 연계 침입방지시스템의 연구)

  • Park Dea-Woo;Lim Seung-In
    • Journal of the Korea Society of Computer and Information
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    • v.11 no.2 s.40
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    • pp.351-360
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    • 2006
  • Proposed security system attacks it, and detect it, and a filter generation, a business to be prompt of interception filtering dates at attack information public information. inner IPS to attack detour setting and a traffic band security, different connection security system, and be attack packet interceptions and service and port interception setting. Exchange new security rule and packet filtering for switch type implementation through dynamic reset memory by real time, and deal with a packet. The attack detection about DDoS, SQL Stammer, Bug bear, Opeserv worm etc. of the 2.5 Gbs which was an attack of a hacker consisted in network performance experiment by real time. Packet by attacks of a hacker was cut off, and ensured the normal inside and external network resources besides the packets which were normal by the results of active renewal.

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Development of needle guidance system and its evaluation for ultrasound-guided follicular aspiration (초음파유도 난포채란기의 개발과 이의 검증)

  • Choi, Min-cheol;Lee, Hyo-jong;Cho, Seong-keun;Kang, Tae-yung;Won, Hyun-hui
    • Korean Journal of Veterinary Research
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    • v.39 no.6
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    • pp.1210-1217
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    • 1999
  • This study was carried out to develop a newly designed ovum pick-up(OPU) instrument for ultrasound-guided transvaginal follicular aspiration in cows. This new instrument consists of out- & inner-layer stainless pipes and a grip with a trigger(hand) switch. Some gauge types of disposable needles and tubes can be attached to this inner pipe. With this instrument, while grasping an ovary with one hand, the other hand can handle in apiration and vacuum on/off with the least assitant's help. With this instrument the mean recovery rate of bovine follicular oocytes was 45.2%. In recovered oocytes, usable oocytes(Grade I & II) were 30.4% and this rate meant 1.4 oocytes per ovary. For 30 days after initial aspiration with this instrument, some adverse effects such as adhesion, hemorrhage, hematoma and other mass formation in/with ovaries were also examined by rectal examination, ultrasonographic and endoscopic images. Adhesion was found in one ovary 1 week after aspiration, and hemorrhagic lesion was found 1-2 days and petechia were found 3-5 days after aspiration and there was no remarkable adverse effects. It was found that this instrument could be applicable and safe for ovum pick-up in cows.

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Microwave-Vacuum Drying of Short Roundwoods and Wood Turneries (단척 통나무와 선반가공목의 마이크로웨이브-진공 건조)

  • Kang, Ho-Yang
    • Journal of the Korean Wood Science and Technology
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    • v.29 no.4
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    • pp.25-32
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    • 2001
  • A microwave vacuum (MW/V) dryer was developed for drying short roundwoods, from which woodcraft souvenirs in Korean market are mostly made, and which were hardly dried without defects in a conventional kiln. It consisted of three 1.5 kW magnetrons of 2,450 MHz, a vacuum pump, a load cell of 100 kg and a cavity of $580{\times}580{\times}1,360\;mm^3$. A computer program was developed to switch on or off the magnetrons according to drying schedules, those were based on microwave injection time or the average of wood temperatures. To evaluate the new MW/V dryer the roundwood specimens of rigida pine, poplar and birch were dried. Their log diameters and lengths ranged from 125 to 25 em and from 25 to 50 cm, respectively. In spite of the presence of minor drying defects, the MW/V drying is found to be an effective method for drying short roundwoods. Wooden turneries made of red alder and ash logs were also MW/V dried from green to 4%MC without any degradation. The rates of the MW/V drying were examined for three different lengths of poplar logs.

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Anti-angiogenic, Anti-cell Adhesion Switch from Halophilic Enterobacteria

  • Lim, Jong Kwon;Seo, Hyo Jin;Kim, Eun Ok;Meydani, Mohsen;Kim, Jong Deog
    • Journal of Marine Bioscience and Biotechnology
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    • v.1 no.3
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    • pp.156-162
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    • 2006
  • The halophilic enterobacteria, Enterobacteria cancerogenus, was isolated from the intestines of the fusiform fish (Trachurus japonicus) to yield a protein-like material termed PLM-f74. PLM-f74 was characterized by strong inhibition ratios to angiogenesis (82.8% at the concentration of $18.5{\mu}g/mL$) and elevated antioxidative capacities with low toxicity. The PLM-f74 is a glycoprotein comprised of saccharides and amino acids. PLM-f74 inhibited non-activated U937 monocytic cell adhesion to HUVECs activated with IL-$1{\beta}$ by 78.0%, and the adherence of U937 cells treated with the PLM-f74 and stimulated with IL-$1{\beta}$ to unstimulated HUVECs decreased by 102%. When both cell types were pretreated with PLM-f74, the adhesion of U937 cells to IL-$1{\beta}$ stimulated HUVECs was completely suppressed by 121% at a concentration of 18.5 ug/mL. PLM-f74 blocked signal pathways from VEGFR2, PI3K, ${\beta}$-catenin and VE-cadherin to NF-kB based on western bolt analysis. And also inhibited IL-1-stimulated HUVEC expression of the adhesion molecules, ICAM-1 by 40%, VCAM-1 by 60%, and E-selectin by 70% at the same concentration noted above. New anti-angiogenic and anti-cell adhesion materials showing elevated antioxidative capacities and non-toxicity may be expected from these results.

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Relationship between Satisfaction with Foodservice and Customer Loyalty of University Students in Busan (부산지역 대학교 급식소의 급식서비스 만족도와 고객충성도와의 관계)

  • Lee, Kyung-A;Lyu, Eun-Soon
    • Korean journal of food and cookery science
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    • v.26 no.4
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    • pp.413-421
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    • 2010
  • The purpose of this study was to improve the satisfaction of college foodservice customers by analyzing the correlation between college student satisfaction with foodservice and customer loyalty. The questionnaire was distributed to 480 customers at six universities in Busan. The average customer satisfaction score was 2.76, and customer satisfaction was highest with food, followed by sanitation, environment, and service (in decreasing order). Customers reported the frequency with which they were satisfied when using university foodservice operations (on an increasing scale from "almost never" to "more than five times") in four areas: food (p<0.001), service (p<0.01), sanitation (p<0.05), and environment (p<0.001). The average scores of customer loyalty, intent to purchase again, intent to advertise by word-of-mouth, and intent to switch were 2.67, 2.83, 2.52, and 2.67, respectively, and these scores demonstrated differences according to frequency of foodservice use (p<0.001). Food, service, sanitation, and environment correlated significantly (+) with customer loyalty. Intent to repeat purchase showed the highest correlation with food quality (p<0.05), and intent to advertise by word-of-mouth and to continue patronizing foodservice demonstrated the highest correlations with service (p<0.01). After classifying customers into four groups according to customer satisfaction and loyalty, a comparison was done to determine satisfaction and loyalty by each customer strata. In the "loyalist" group, satisfaction with environment and the intent to advertise by repurchase were significantly higher than in the other groups (p<0.001). In "defectors" group, satisfaction with service and the intent to advertise by word-of-mouth were significantly lower than in the other groups (p<0.001).

Study on Post-Fire Safe Shutdown Analysis using an Imaginary Plant for Training (교육용 가상원전을 이용한 화재안전정지분석에 관한 연구)

  • Lee, Jaiho;Kim, Jin Hong
    • Fire Science and Engineering
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    • v.32 no.1
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    • pp.57-65
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    • 2018
  • In this study, a post-fire safe shutdown analysis (PFSSA) including multiple spurious operation (MSO) treatments for cables was conducted with an imaginary nuclear power plant for training using a deterministic fire analysis code. The imaginary nuclear power plant for the training consisted of a reactor containment building and an auxiliary building, including a total of 22 fire areas. The equipment including valves, pumps, emergency diesel generators, switch gears, motor control centers, and logic controllers were located in each fire area of the imaginary plant. It was assumed that each equipment is connected with two cables and that each cable passes through the fire areas along the cable trays. A database containing the information on the equipment and cables for the imaginary plant was constructed for the fire area analysis. The fire area analysis was performed for several assumed MSO scenarios, equipment logics, and cable logics. A mitigation measure using a three hour rated wrap was applied to the failed cables and cable trays after the fire area analysis.

A new power-stage design and analysis to modularize power regulator of the KOrea Multi-Purpose SATellite (다목적 실용위성 전력조절기 모듈화 구현을 위한 새로운 전원단 설계 및 해석)

  • 박성우;이재승;이종인;윤정오
    • Journal of Korea Society of Industrial Information Systems
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    • v.8 no.2
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    • pp.84-91
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    • 2003
  • KOMPSAT series use software-controlled unregulated bus system in which the main bus is directly connected to a battery and the duty-ratio for PWM switch is controlled by the on-board satellite software. This paper proposes a new power-stage circuit that can be available for modularization of the power regulator which is used at the software-controlled unregulated bus system satellite. And we analyze the proposed power-stage operation according to its operating modes and verify it by performing software simulation and hardware experiment using prototype. We construct a parallel-module converter which is composed of proposed power-stages and perform experiment to verify modular characteristics of the proposed power-stage. Finally, we verify the usefulness of the proposed power-stage by comparing above results with those of a parallel-module converter made of conventional power-stages.

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Performance Analysis of Cross-Layer Handoff Scheme in IP-Based Next-Generation Wireless Networks (IP기반 차세대 무선 네트워크에서의 교차계층 핸드오프 기법의 성능 분석)

  • Lee, JaeSuk;Jeong, Jongpil
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38B no.6
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    • pp.454-472
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    • 2013
  • The development of wireless network technology and the increasing use of wireless networks to mobile users with a variety of wireless network systems has arisen. Wireless sensor networks, they can be nested together, and the need to switch between the network, depending on your needs. Next Generation Wireless Networks(NGWN) gives the mobile user a wide coverage and optimized service etc. Previous hand off management protocol is not enough to secure support of the NGWN application program. Cross-layer Handoff(CLH) protocol technique has been developed to support between and inside networks of handoff management of NGWN. CLH supports mobility management in a wireless network environment and also utilizes mobility speed and handoff signaling delay information to improve the handoff performance ability. For the analysis of handoff performance ability, we analyzed sensitivity of link layer and network layer, therefore, CLH technique is suggested based on this analysis.

Inhibitory Effect of Immunoglobulin E Production by Poncirus tripoliata (지실(枳實)에 의한 면역(免疫)글로블린 E 생성(生成)의 억제효과(抑制效果))

  • Kim, Hyeong-Kyun;Kweon, Yong-Taek
    • The Journal of Korean Medicine
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    • v.19 no.1
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    • pp.419-429
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    • 1998
  • Poncirus trifoliata (L.) Raf (Rutaceae) fruits (PTFE) has been used for the treatment of allergic disease. IgE is normally one of the least abundant immunoglobulin (Ig) isotypes in the serum of both humans and several species of experimental animals: however a number of different stimuli can result in profound increases in IgE levels relative to other isotypes. In rodents, infection with many parasitic helminths can cause approximately 100-fold elevation in IgE within 2 wks. Immunization of mice with small amounts of protein antigens on alum also results in 10-fold to fold increase in total serum IgE, much of it specific for the immunizing antigen. In this experiment, I investigated the effect of an aqueous extract of Poncirus trifoliata (L.) Raf (Rutaceae) fruits (PTFE) on a in vivo and in vitro IgE production. PTFE dose-dependently inhibited the serum levels of IgE induced by antigens. The regulation of IgE synthesis is influenced by T cells and T cell derived factors. IL -4, a T cell-derived cytokine, has been shown to stimulate murine IgE synthesis both in vitro and in vivo. Current evidence suggests that IL-4 induces IgE synthesis in the mouse by stimulating H chain isotype switch. Lipopolysaccharide (LPS) plus IL-4 cause about l00-fold increase in IgE secretion by murine B cells. The effects of PTFE on the IL-4-dependent IgE response by mouse whole spleen cells were studied. Whole spleen cells were cultured for 7 days in the presence of LPS plus IL-4 and PTFE and the supernatants were assayed for IgE. IL-4 dependent IgE production of LPS-stimulated whole spleen cells was inhibited by PTFE. Moreover, in the present study using U266Bl human IgE-bearing B cells, I found that PTFE inhibited the production of IgE activated by LPS plus IL-4. These results indicate that PTFE have antiallergic activity by inhibition of IgE production from B cells.

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Clinical features and surgical outcomes of complete transposition of the great arteries

  • Hong, Suk Jin;Choi, Hee Joung;Kim, Yeo Hyang;Hyun, Myung Chul;Lee, Sang Bum;Cho, Joon Yong
    • Clinical and Experimental Pediatrics
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    • v.55 no.10
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    • pp.377-382
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    • 2012
  • Purpose: This single-center study aimed to assess the clinical features and surgical approaches and outcomes of complete transposition of the great arteries (TGA). Methods: TGA patients who had undergone surgical correction at the Kyungpook National University Hospital from January 2000 to December 2010, were retrospectively evaluated for patient characteristics, clinical manifestation, preoperative management, intraoperative findings, postoperative progress, and follow-up status. Results: Twenty-eight patients (17 boys and 11 girls, mean age=$10.6{\pm}21.5$ days) were included and were categorized as follows: group I, TGA with intact ventricular septum (n=13); group II, TGA with ventricular septal defect (VSD, n=12); and group III, TGA/VSD with pulmonary stenosis (n=3). Group I underwent the most intensive preoperative management (balloon atrial septostomy and prostaglandin E1 medication). Group II showed the highest incidence of heart failure (P<0.05). Usual and unusual coronary anatomy patterns were observed in 20 (71%) and 8 patients, respectively. Arterial and half-turned truncal switch operations were performed in 25 and 3 patients (Group III), respectively. Postoperative complications included cardiac arrhythmias (8 patients), central nervous system complications (3 patients), acute renal failure (1 patient), infections (3 patients), and cardiac tamponade (1 patient), and no statistically significant difference was observed between the groups. Group II showed the mildest aortic regurgitation on follow-up echocardiograms (P<0.05). One patient underwent reoperation, and 1 died. The overall mortality rate was 4%. Conclusion: Our study showed favorable results in all the groups and no significant difference in postoperative complication, reoperation, and mortality among the groups. However, our results were inadequate to evaluate the risk factors for reoperation and mortality owing to the small number of patients and short follow-up duration.