• 정보처리학회논문지C
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• 제11C권7호
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• pp.1023-1032
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• 2004

이동 통신 시스템에서 핸드오프는 패킷 손실, 전송 지연, 지터 등을 유발하여 사용자의 서비스 품질을 저하시킨다. 더욱이 차세대 이동 통신 시스템으로 주목받고 있는 OFDM(Orthogonal Frequency Division Multiplexing) 시스템에서는 OFDM 특성 상 하드 핸드오프를 수행해야 하고, 높은 용량의 마이크로 셀과 빠른 속도의 단말로 인해 핸드오프 주기가 잦아진다. 따라서 핸드오프 시 유발되는 서비스 품질은 3세대 이후의 이동 통신 시스템의 성능을 결정짓는데 매우 중요한 요소가 된다고 볼 수 있다. 그러므로, 이를 위해 핸드오프 시 QoS를 보장해 줄 수 있는 알고리즘에 대한 연구가 절실히 필요하다. 지금까지 차세대 이동 통신 시스템을 위한 기존 연구들은 IP 계층에서 L3 핸드오프 지연이나 L3 패킷 손실을 줄이는데 만 주력해 왔다. 즉 MAC 계층과 같은 2계층의 핸드오프 지연을 줄이기보다는 3계층에서 보상하는 방식으로 핸드오프지연을 줄여 온 것이다. 하지만 여전히 존재하는 L2 지연은 실시간 트래픽과 같은 지연 민감 서비스 등에서 QoS를 크게 저하시키게 된다. 따라서 본 논문에서는 L2 핸드오프 지연을 최소화할 수 있는 끊김 없는 핸드오프 알고리즘을 제안한다.

• IMMUNE NETWORK
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• 제11권1호
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• pp.68-78
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• 2011

Background: Graft-versus-host disease (GVHD) is a huddle for success of hematopoietic stem cell transplantation. In this study, effects of irradiation dose on immune kinetics of GVHD were investigated using B6 ${\rightarrow}$ BALB.B system, a mouse model for GVHD after MHC-matched allogeneic transplantation. Methods: BALB.B mice were transplanted with bone marrow and spleen cells from C57BL/6 mice after irradiation with different doses. Leukocytes residing in the peripheral blood and target organs were collected periodically from the GVHD hosts for analysis of chimerism formation and immune kinetics along the GVHD development via flow cytometry. Myeloid cells were tested for production of IL-17 via flow cytometry. Results: Pre-conditioning of BALB.B hosts with 900 cGy and 400 cGy resulted in different chimerism of leukocytes from the blood and affected survival of GVHD hosts. Profiles of leukocytes infiltrating GVHD target organs, rather than profiles of peripheral blood leukocytes (PBLs), were significantly influenced by irradiation dose. Proportions of IL-17 producing cells in the infiltrating $Gr-1^+$ or $Mac-1^+$ cells were higher in the GVHD hosts with high does irradiation than those with low dose irradiation. Conclusion: Pre-conditioning dose affected tissue infiltration of leukocytes and cytokine production by myeloid cells in the target organs.

• Journal of Microbiology
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• 제40권2호
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• pp.91-97
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• 2002

Enteroaggregative E. coil (EAEC) is an important aethiological causal agent of diarrhea in people of developed and undeveloped countries. Different in vitro and in vivo models have been proposed to study the pathdgenic and immune mechanisms of EAEC infaction. The aim of this study was to analyze whether BALB/c mice could be used as an animal model to study EAEC pathogenesis Six-week-old BALB/c mice were inoculated with EAEC strain 042 (044:H88) nalidixic acid resistant, and re-inoc-ulated ten days after. Mice feces were monitored for the presence of the EAEC strain over a period of 20 days . Bacteria were enumerated on MacConkey agar containing 100$\mu$g of nalidixic acid per ml. Results showed that 35% of the animals were colonized for 3 days, 15% for 5 and 10% for more than 7 days . After re-inoculation only 16% of the animals remained colonized for more than 3 days. During the necropsy, the intestinal fluid of same of the infected animals presented mucus and blood. Six of these fluids showed the presence of IgA antibodies againset Pet toxin and IgG natibodies raised against the toxin were also detected in the animal serum. Histopathologic evidence confirms the stimulation of mucus hypersecretion, an increased amount of goblet cells and the presence of bacterial aggregates in the apical surfaces of intestinal epithelial cells. Edema was present in the submucosa. These results suggest that BALB/c mice could be used as an animal model for in vivo study of EAEC infection.

• 한국어류학회지
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• 제36권2호
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• pp.199-206
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• 2024

전갱이과(Carangidae) 어류에 속하는 1개체가 제주도 서귀포시 서귀동에서 2023년 10월 16일에 낚시로 처음 채집되었다. 본 개체는 측선이 제1 등지느러미 아래에서 완만하게 굴곡되어 있는 점, 흉부에 무린 영역이 존재하는 점, 새파수가 26개인 점 등에서 Caranx papuensis로 동정되었다. 또한 mtDNA COI 영역 619 bp를 분석한 결과 일본산 C. papuensis와 유전거리 0.54%로 잘 일치하였다. 국내에 처음 보고되는 본 종의 국명으로 측선을 따라 황색 줄을 가지는 특징에 의거 "황줄전갱이"를 제안한다.

• IMMUNE NETWORK
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• 제24권2호
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• pp.17.1-17.16
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• 2024

We have reported that anterior cruciate ligament (ACL) injury leads to the differential dysregulation of the complement system in the synovium as compared to meniscus tear (MT) and proposed this as a mechanism for a greater post-injury prevalence of post traumatic osteoarthritis (PTOA). To explore additional roles of complement proteins and regulators, we determined the presence of decay-accelerating factor (DAF), C5b, and membrane attack complexes (MACs, C5b-9) in discarded surgical synovial tissue (DSST) collected during arthroscopic ACL reconstructive surgery, MT-related meniscectomy, osteoarthritis (OA)-related knee replacement surgery and normal controls. Multiplexed immunohistochemistry was used to detect and quantify complement proteins. To explore the involvement of body mass index (BMI), after these 2 injuries, we examined correlations among DAF, C5b, MAC and BMI. Using these approaches, we found that synovial cells after ACL injury expressed a significantly lower level of DAF as compared to MT (p<0.049). In contrast, C5b staining synovial cells were significantly higher after ACL injury (p<0.0009) and in OA DSST (p<0.039) compared to MT. Interestingly, there were significantly positive correlations between DAF & C5b (r=0.75, p<0.018) and DAF & C5b (r=0.64 p<0.022) after ACL injury and MT, respectively. The data support that DAF, which should normally dampen C5b deposition due to its regulatory activities on C3/C5 convertases, does not appear to exhibit that function in inflamed synovia following either ACL injury or MT. Ineffective DAF regulation may be an additional mechanism by which relatively uncontrolled complement activation damages tissue in these injury states.

• 전자통신동향분석
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• 제24권3호
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• pp.91-102
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• 2009

FCC(Federal Communications Commission 미국 연방통신위원회)는 2008년 11월 스펙트럼 사용 효율을 높이고 새로운 서비스 도입을 용이하게 하기 위해 TV White Spaces를 대상으로 주파수 공유 기술인 Cognitive Radio 기술을 적용하기로 하고 관련 규정을 개정하였다. FCC는 TV White Spaces에서 고정 서비스와 개인/휴대서비스기기 사용을 허용하기로 방침을 정하고 2009년 5월 12일 DTV 전환 완료 이후 관련 기기 사용을 허용하기로 하였다. 본 논문에서는 FCC의 법규 개정 현황과 함께 이를 기술적으로 뒷받침하기 위한 IEEE 802.22, TV White Spaces ECSG, ECMA에서의 표준화 동향을 설명하고, 핵심 기술로서 스펙트럼 센싱 기술, 무선자원관리 기술, PHY/MAC 관련 기술 개발 동향에 대해 요약 기술하였다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2009년 춘계학술대회논문집
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• pp.239-244
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• 2009

The gridless (or meshfree) methods, such as MPS, SPH, FPM an so forth, are feasible and robust for the problems with moving boundary and/or complicated boundary shapes, because these methods do not need to generate a grid system. In this study, a gridless solver, which is based on the combination of moving least square interpolations on a cloud of points with point collocation for evaluating the derivatives of governing equations, is presented for two-dimensional unsteady incompressible Navier-Stokes problem in the low Reynolds number. A MAC-type algorithm was adopted and the Poission equation for the pressure was solved by successively in the moving least square sense. Some weighing functions were tested in order to investigate the up-winding effect for the convection term. Some typical problems were solved by the presented solver for the validation and the results obtained were compared with analytic solutions and the numerical results by conventional CFD methods, such as FVM.

• Progress in Superconductivity
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• 제5권1호
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• pp.5-8
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• 2003

We studied the effect of spin injection on tunneling conduction properties of intrinsic Josephson junctions formed in $Bi_2$$Sr_2$$CaCu_2$$O_{ 8＋x}$ single crystals. properties of an identical stack (10${\times}$5.0${\times}$0.030 $\mu\textrm{m}^3$) of intrinsic Josephson junctions were compared for the bias current injected through Au and Co electrodes. The suppression of the superconducting gap in the $_2$ double layers and the interlayer Josephson critical current was manifested in the tunneling current-voltage characteristics of the stacks. This effect appears to be caused by the pair breaking associated with spin-polarized carriers injected from the Co electrode into the $Bi_2$$Sr_2$$_2$O$CaCu_{ 8＋x}$ single crystal. This study may provide valuable information on clarifying the mechanism of high- $T_{c}$ superconductivity.y.y.

• 한국동물위생학회지
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• 제32권3호
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• pp.215-218
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• 2009

The dog breeding kennel bacterial infection are very significant in perinatal mortality. In many case, Staphylococcus aureus, Streptococcus, and Escherichia coli were infected in intra-uterine or by the genital tract to the puppies, and they are cause of septicemic death of the puppies and clinical mastitis of bitch, leading to septicemic death of newborn puppies. Severe mastitis due to bacterial infection was diagnosed in a 2 year-old female Brittany Spaniel which loss 6 puppies with odor small rice sharp white diarrhea of nine puppies. Bright curd milk and intestinal sample were inoculated on MacConkey agar, blood agar and brain heart infusion agar, and incubated at $37^{\circ}C$ for 24-48 hrs. Gram negative colonies isolated from these sample which were characterized as Glu, Ure, $H_2S$, Orn, Cit, and Cl, and were identified by Microscan Walk-Aways Baxter, American Type Culture Collection, USA) as Proteus mirabils. The isolate was more sensitive to ampicillin, gentamicin, cefoxitin, cefuroxime, and cefazidime. In this results, we confirmed that cause bacteria of septicemic death in puppies was P. mirabilis.

• 한국의상디자인학회지
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• 제2권1호
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• pp.113-121
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• 2000

The effect of Sunlight exposure on reducing the microorganism counts in the bedding materials was experimented by using 3 kinds of microorganisms(S. aureus, K. pnenmoniae and E. coli) and 3 kinds of fabrics (cotton, silk and polyester). Counts of the microorganism were examined before and after sunlight exposure. The sunlights were controlled U.V and Daylight D50 using MacBeth artificial light source. The specimens were exposed for 5 min, 10 min and 30 minutes under the $20^{\circ}C$ and 60% R.H, distance is 50cm from the light source. Results were as follows, 1. The reduction rate of the 3kinds of microorganisms was remarkably great under the U.V exposure. The U.V. exposure was very effective way to sterlize the bedding materials in the house care. 2. S. aureus was the most susceptible to U.V. exposure and the sunlight exposure. E. coli was the most resistant to the U.V and the sunlight exposure. 3. The reduction rate of the 3 kinds of fabrics was not significantly different. The polyester is more resistant than the silk and the cotton. Those were shown good reduction rate if all kinds of microorganism under the U.V and daylight.