Overlay 기반의 WiBro와 WLAN 이종망 연동을 위한 Vertical 핸드오버 구현 및 성능 측정에 관한 연구

이재호,류형근,강선무,이재용,김승천 한국정보사회진흥원 2007 정보화정책 Vol.14 No.3

유비쿼터스 사회를 위한 미래 네트워크는 다양한 이종 무선망이 혼합된 형태가 될 것으로 예상되고 있다. 본 논문에서는 개별 무선망의 특징을 최대한 활용하여 1,270,000㎡ 면적의 KAIST(Korea Advanced Institute of Science and Technology) 대학교 캠퍼스에 IEEE 802.16e/WiBro와 IEEE 802.11/WLAN 를 복합적으로 설치하여 건물외부에서는 WiBro, 건물내부에서는 WLAN으로 자동 스위칭 되는 Vertical 핸드오버 System을 구축하고 이동 성능을 분석하였다. 이종망 통합 과정에서 제조사 및 통신사업자의 사정으로 인하여 Mobile IP를 지원하지 않는 라우터들이 존재하였고, 특히 현재 WiBro에 사용되는 ACR(Access Control Router)은 Mobile IP를 지원하지 않기 때문에 이를 해결하기 위하여 Overlay 기반의 Mobility 기법을 적용하였다. 본 연구에서는 실제로 대규모 통신망을 구현하고, 이에 대한 성능시험을 시행한 후 handover delay 시간 분석을 통한 현장 적용 가능성 및 개선 필요사항을 도출하였다. 그 결과 이종망간 핸드오버 시간은 평균 2.58초로써 일반 데이터 서비스는 이종망간 연속성이 보장됨을 확인하였고, 음성∙영상과 같은 실시간 서비스는 중간에 지연시간이 발생하나 응용서비스 세션 자체는 유지됨을 확인하였다. The future network is forecast with the fact that the form where the various heterogeneous wireless networks. In this paper we build both IEEE 802.16e/WiBro and IEEE 802.11/WLAN network on the KAIST(Korea Advanced Institute of Science and Technology) campus(1,270,000m2) as well as established the vertical handover system which supported WLAN in the building and WiBro outside the building. A Mobile IP is considered for the efficient vertical mobility function in IEEE 802.16/WiBro and IEEE 802.11/WLAN environment. However, during the deployment of WiBro, only some of the ACRs(Access Control Router) can support the Mobile IP function. Therefore, WiBro network can not support the mobility function for the mobile node. In this paper, we implement an overlay-based Mobile IP function and measure the performance through a field trial. Moreover, we evaluate the possibility of commercial deployment and suggest areas that need to be improved. The average handover time between WiBro and WLAN was 2.58 seconds. As a result, the user application session maintained but real time applications were delayed during the handover time.

SHS법에 의한 TiC-Al₂O₃계 세라믹스의 합성 및 소결특성

이형복,김성수,편무실,최덕배 明知大學校 産業技術硏究所 1991 産業技術硏究所論文集 Vol.10 No.-

TiC-Al₂O₃ system powders were prepared by the self-propagating high temperature synthesis method from the mixture of metal titanium, carbon and alumina powder, Powder and sintering characterization of TiC-Al₂O₃ system were investigated. TiC-15wt% Al₂O₃ compacts sintered by hoy-pressing under the pressure of 20MPa at 1850 for 90 minutes showed 3-point bending strength of 724Mpa, ?? of ??????, hardness of 2450㎏/㎟ and relative density of 97%. The combustion mode of combustion wave showed steady-state up to 15wt% Al₂O₃, spin above 20wt% Al₂O₃ also combustion velocity was decreased with increasing of Al₂O₃ contents.

家兎網膜 神經節細胞의 總數와 分布에 關한 硏究

李亨周,金武剛 충남대학교 의과대학 지역사회의학연구소 1985 충남의대잡지 Vol.12 No.1

The number and distribution of the retinal ganglion cells in the rabbit was determined from whole flat mounted preparations stained with methylene blue and thionin. The results were summarized as follows. 1. The total number of retinal ganglion cells was estimated to be 903,600 in retina ranging from 641㎟ in total area. 2. The number of alpha type ganglion ceils(above 15 microns) was 118,000 in the retina of rabbit and constituted 13% of the total cells. 3. The visual streak was recognized above 2.5mm from optic disc and ganglion cell density drops off rapidly above and below the visual streak. 4. Area centralis(8,300/㎟) was recognized at the area of 10mm temporally, from the point of 2.5mm superior to the optic disc. 5. The relative frequency of the alpha type ganglion cells was higher in the superior-nasal quadrant than in other region of the retina.

실험 방광암 모델에 있어서 Proliferating Cell Nuclear Antigen이 발현되는 세포들의 색상-화상 분석

이현무,이태수,김원재,차은종,송형근 충북대학교 의과대학 충북대학교 의학연구소 1993 忠北醫大學術誌 Vol.3 No.1

Proliferating cell nuclear antigen(PCNA)에 대한 단클론성 항체에 의해 면역조직화학적으로 염색된 세포들의 평가에 있어서 색상-화상 분석의 역할을 살펴보고자 하였다. BBN 투여 기간에 따라 Fisher 344 백서 방광에 정상 상피로부터 단순 과증식, 결절성 혹은 유두상 과증식 및 표재성 방광암에 이르는 순차적인 병리세포학적 변화가 발생함을 관찰한 후, 이를 색상-화상 분석과 육안적 분석을 통해 PCNA에 대한 평균 labeling index를 구한 결과 두가지 방법에서 모두 각 병변 사이에 통계적으로 유의한 차이를 보였으나, 색상-화상 분석을 이용하여 구한 평균 labeling index의 변이계수가 육안적 분석을 이용하여 구한 평균 labeling index의 변이계수에 비해 전 병변에 대하여 낮게 나타나, 종양화과정이 진행함에 따라 PCNA에 대한 평균 labeling index가 증가하고 평균 labeling index가 높을 수록 증식도가 더 큼을 나타낸다는 결과를 얻었으며, 색상-화상 분석을 이용하여 얻은 결과가 육안적 분석을 이용하여 얻은 결과보다 신뢰도가 더 높은 것으로 나타났다. 이와같은 면역조직화학염색에 대한 색상-화상 분석을 통한 세포역동학적 연구는 정량화 및 재현성의 향상을 통해 면역조직화학염색의 평가에 있어 보다 신뢰도가 높은 정보를 제공하여줄 것이며, 이를 통해 방광종양의 증식도 및 악성도를 예측하는데 중요한 역할을 할 것으로 생각된다. A study was carried out to define the role of color-image analysis in evaluation of immunohistochemically labeled cells using anti-PCNA/cyclin monoclonal antibody. Sequential cellular changes(normal, simple hyperplasia, nodular or papillary hyperplasia, and transitional cell carcinoma-Ta, T1) were observed in Fisher 344 rat urinary bladder depending on the duration of BBN administration. The mean PCNA labeling index obtained by color-image analysis and visual analysis in normal, simple hyperplasia, nodular or papillary hyperplasia and bladder tumor showed statistically significant difference in each histological group. But coefficients of variation of mean PCNA labeling index obtained by color-image analysis were lower than those using visual analysis in all lesions. Higher PCNA labeling indices indicated greater biological malignant potential, and mean labeling index in each histological group obtained by both color-image and visual analysis progressively increased with tumorigenesis, but the coefficient of variation with color-image analysis was lower than that with visual analysis in general, therefore, the evaluation of labeling indices obtained using color-image analysis was more reliable than that obtained using visual analysis. The data suggest that cell kinetic evaluation using color-image analysis may provide more reliable information to evaluate immunohistochemical staining in terms of quantitation and reproducibility and play an important role in predicting proliferative activity and malignant potential for bladder tumor.

JCAD3을 이용한 장신구 디자인에 대한 연구 : 렌더링 디자인을 중심으로

이무형 啓明專門大學 産業開發硏究所 2000 啓明硏究論叢 Vol.18 No.2

지금까지는 귀금속을 전공한 많은 디자이너들이 자신들의 디자인을 직접 손으로 렌더링하여 제작하였다. 그러나 산업사회의 결정적 산물인 컴퓨터의 발달로 인해 선진국에서는 과학적인 컴퓨터 프로그램을 이용하여 효율적인 렌더링을 창출하고 있다. 이러한 사실에 기인하여 본 논문은 JCAD3 컴퓨터 프로그램을 이용해 현대인의 인간적 요구에 부합되는 합리적인 장신구 렌더링을 개발하는데 목적을 두고 있다. 이것을 위하여 장신구의 문화적 배경. JCAD3 장신구의 디자인 실태, 장신구사용자의 기호조사, JCAD3 프로그램의 특성 등 관련자료를 조사, 분석하였다. 이러한 것들을 토대로 하여 본 연구의 디자인 방향을 설정하였으며 문제해결을 위한 代案을 구성하였다. 그리고 구성된 여러 代案 중 이상적인 것을 선택하여 試案으로 제시하였다 이러한 연구의 결과는 현대사회가 요구하는 합리적인 장신구 디자인 개발로 이어져 예술문화발전에 기여할 것으로 생각한다. Many designers who majored the precious metal have usually rendered their own design by themselves for a long time. However, developed countries started to make rendering designs effective through scientific computer programs, after the industrial society invented the computer. Based on this situation, the purpose of this study is to develop rendering accessory designs corresponding to the modern's need by using JCAD3 computer program. For this there were researches on the actual design condition of JCAD3 accessory, the favor of users. and the cultural background of accessories. Then the ideal one was presented among several alternative plans. It is expected that the result of these researches will contribute to the proper accessory design development which the modern society requires.

Postweaning Multisystemic Wasting Syndrome (PMWS)에 이환된 자돈에 대해 Porcine circovirus 2 Rep 유전자 검출에 관한 연구

이용훈,김지영,楚佳奇,서상희,장경수,김명철,박창식,전무형 충남대학교 수의과대학 동물의과학연구소 2004 動物醫科學硏究誌 Vol.12 No.-

Postweaning multisystemic wasting syndrome (PMWS) is a new emerging disease in swine herds world wide, and porcine circovirus type 2 (PCV2) is known as a major cause of PMWS. In this study, the prevalence of PCV2 Rep gene was examined for the serum, nasal swabs and feces collected from 30 heads of piglets affected with PMWS and 10 heads of normal healthy piglets using polymerase chain reaction (PCR). The diagnostic efficiency of the PCR was evaluated for different types of samples. Rep gene of the isolate (PCV2 S1) was then sequenced. In the group of PMWS-affected piglets, the prevalence of PCR-positive were 70.0% in sera, 33.3% in nasal swabs and 0% in feces. In the normal healthy group, the PCR-positive rates of sera, nasal swabs and feces were 30%, 20% and 0%, respectively. Seven piglets (17.5%) out of 40 showed the simultaneously positive results in both of sera and nasal swabs. The nucleotide sequence homology of Rep gene of PCV2 S1 as compared with the reference strain of PCV2 (GenBank accesson no.AF027217) was 99.3%.

2 Parameter Criterion을 이용한 안정성 평가에 관한 연구

이종형,유덕상,박무수 國立金烏工科大學校附設生産技術硏究所 1997 産業技術開發硏究 Vol.13 No.-

In this paper, the following results about character stics of surface fatigue crack are obtained by △p decreasing experiment and crack generation using SPPS 42 of pipe-use carbon steel. The △Kthe of surface crack is smaller than the △Kth of through crack. Therefore, if the △Kth of through crack is used as defect estimation, it becomes dangerous. The validity of Engineering safety is represented establishing fatigue fracture estimation diagram by the 2 parameter criterion of threshold and fatigue limit.

생태단지계획기법의 수립에 관한 기초연구

이영무,문형택 홍익대학교환경개발연구원 2000 환경개발연구논문집 Vol.5 No.-

The purpose of this thesis is the establishment of basic guidelines to create an ecologically sound apartment complex. The case studies of foreign and korean eco-site planning lead to the extraction of basic principles that should be applied in realization of ecologically healthy apartments. The guidelines consist of six categories and these principles are desired to apply to the planning process of future apartment complex. The first is the application of environment friendly housing construction techniques. This includes solarium, indoor garden, balcony garden and greening of apartment outer walls. The second is the recycling of resources. It involves recycling of wastes, compost making, water retention and purification. The third is the creation of biotope. It means the designing of fish pond, stream and paving with permeable material. The insects such as butterflies and dragonflies are encouraged to settle in the biotope. The fourth involves the creation of green network within the complex. It consists of various gardens and eco-corridors which connect the greeneries. The system eventually leads to invitation of not only insects and birds but also small mammals like squirrels. The fifth is the harmonizing of the apartments with the existing topography. It means the preservation of the forst, minimizing the soil removal and positioning of buildings to fit the natural energy. The sixth includes active and passive harnessing of sun, wind and geo-thermal energy extraction. Above techniques are recommended to be utilized actively in the planning process of healthier apartment construction to achieve the goal of UN resolution of Rio de Janeiro in 1992 which states the 'Environmentally Sound and Sustainable Development' in order to continue the symbiosis of human race and the nature.

忠南地域 屠畜豚의 肺病變으로부터 分離한 Actinobacillus pleuropneumoniae의 生物學的 및 免疫學的 特性

이종훈,장경수,장치훈,김일택,정용성,김귀현,전무형 충남대학교 수의과대학 동물의과학연구소 1996 動物醫科學硏究誌 Vol.4 No.-

An epidemiologic study on pleuropneumonia in the slaughter pigs(Chonan and Asan area, Chungnam province, Korea) during the period of January 1994 through December 1995 was conducted. Isolation of A. pleuropneumoniae was attempted in 425 pigs with pneumonic lesions. Biochemical properties, antimicrobial susceptibility, serotypes and pathogenicity of A. pleuropneumoniae isolates were investigated. In addition, outer membrane protein(OMP) of the isolates were extracted to determine its properties and immunogenicity in both mice and piglets. Of 3,395 slaughter pigs, pleuropneumonia was observed in 425 pigs(10.6%). A. pleuropneumoniae was isolated from 22 pigs(5.2%) out of 425 pigs with pneumonic lesions. The biochemical properties of all isolates were same as those of reference A. pleuropneumoniae strain. Among 22 isolates, 9, 1 and 12 isolates were serovar 2, 3 and 5, respectively. The results of antimicrobial susceptibility test revealed that the isolates showed high susceptibility to ciprofloxacin and cephalothin, moderate susceptibility to amikacin, gentamicin, kanamycin and streptomycin, and low susceptibility to erythromycin, tylosin and sulfadimethoxin. The isolates were varied in pathogenicity to mice. Median lethal dose of LE9402(serovar 2) and LE9511(serovar 5) were 9.2×10^7CFU and 2.8×10^7CFU, respectively. Specific pneumonic lesions were observed from the infected mice with clinical signs. Bacteria recovery rate was high in the lung, but low in heart blood and tracheas. Serovar 2 was found to be more pathogenic than serovar 5 in guinea pig. Mortality on guinea pigs inoculated with serovar 2(5.4×10^8 - 5.4×10^6CFU) abd serovar 5(2.8×10^8 - 2.8×10^6CFU) was 20-40% and 40-80%, respectively. A severe hemorrhagic lesions and focal pneumonic lesions were observed from dead guinea pigs. Bacteria recovery rate was relatively higher in the lung than that of other organs. In the SDS-PAGE analysis, OMP-enriched fractions of both isolates and reference strains contain common peptide bands equivalent to molecular weight of 17, 27, 42, 52 and 95Kd. In addition to common peptide bands, the bands which are specific to each isolate were also observed. The profiles of Sephadex G25 fractions showed 3 major peaks. The common peptide bands which were observed by SDS-PAGE of the crude OMPs were found i the peaks 1 and 2. The OMPs extracted from serovar 2(LE9402) and serovar 5(LE9511) provided high level of protection in mice(70-80%) and pigs(100%). All animals inoculated with OMPs were seroconverted, showing micro-agglutination titer of 640 to 1280.

ARTCLAY를 이용한 BROOCH DESIGN에 대한 연구

이무형 啓明專門大學 産業開發硏究所 1999 啓明硏究論叢 Vol.17 No.2

현대인의 미적 욕구를 충족시키기 위한 장신구 디자인 개발문제는 공예산업적 측면에서 뿐만 아니라 문화적인 측면에서도 매우 중요한 과제이다. 본 연구는 이러한 중요성에 입각해 경제적이고도 합리적인 아트클래이 브로치 디자인을 개발하는데 목적을 두고 있다. 이것을 위하여 생산된 아트클래이 제품의 디자인 특성을 분석하고 아트클래이 재료 및 기법에 대하여 조사하였다. 이러한 관련자료를 통하여 본 연구가 추구하는 디자인의 방향을 설정하였으며 이를 토대로 하여 代案을 구성하였다. 그리고 대안의 장·단점을 분석 한 다음 이상적인 것을 선택해 試案으로 제시하였다. 본 연구를 통한 결과는 시대적 요구에 적합한 공예품 제작에 도움이 될 것으로 여겨지며 향후의 문화 발전에도 기여될 것으로 생각한다. The study was about developing brooch design using artclay material. The purposes of the study were to research the historical background of the brooch(accessories), how the artday product is distributed, and to explain the characteristics of the artclay product. Through the material concerned, I could decide upon the direction of the study, and put forward an alternative for effective artclay brooch design. Analyzing the merits and weak points, I selected the ideal design and manufactured a brooch for display. The study is useful for developing craft work which is appealing to people's needs of the day. I expect the study will be helpful for improving culture.