• Title/Summary/Keyword: Surrounding

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Implementation of IPv6 Neighbor Discovery Protocol supporting CGA

  • Kim Joong Min;Park In Kap;Yu Jae Wook
    • Proceedings of the IEEK Conference
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    • 2004.08c
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    • pp.571-575
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    • 2004
  • Having age of ubiquitous ahead, existing IPv4's address space insufficiency phenomenon appears because of increasing network usage as well as multimedia data transmission becomes much, necessity of new IP address system that guarantee QoS are needed. IPv6 was made to solve these problem. IPv6 solves address space insufficiency phenomenon offering by 128bit address space, and also offers hierarchical address layer that support improved QoS. IPv6 defines relation between surrounding node using Neighbor Discovery protocol. Used Neighbor Discovery messages, grasp surrounding node, include important informations about network. These network information outcrops can give rise in network attack and also service that use network will paralysis. Various kinds of security limitation was found in Present Neighbor Discovery protocol therefore security function to supplement tris problem was required. In this thesis, Secure Neighbor Discovery protocol that add with security function was design and embody by CGA module and SEND module.

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A Study on the Characteristics of Propagation and Effects of Vibration by Sand Drain Method in Construction Field (건설현장에서의 Sand Drain 시공에 의한 진동특성과 영향에 관한 연구)

  • Kwak, Kwang-Soo;Kim, Jae-Soo
    • KIEAE Journal
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    • v.1 no.2
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    • pp.13-19
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    • 2001
  • Recently, With the increase of income level, many people desire to have agreeable and quiet surrounding. However, the extent and time of the exposure to construction noise and vibration is increasing, which is a factor that ruins the quietness of the surrounding and increasingly raises interests in its effects. In this point, this study attempts to survey the characteristics of construction vibration by SD(Sand drain) method in construction field. In addition, the result of study is presumed to be usable as the fundamental materials for an efficient counter-plan in case of the public resentment in relations to the construction vibration occurring henceforth.

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Experimental study of heat transfer in the surrounding for bubble attached at the upper cooled surface of square cavity using the Thermo-sensitive Liquid-crystal Tracer (열감응액정을 이용한 사각공동내의 상단냉각평판에 형성된 기포 주위의 열전달현상 구명)

  • Kwon, Gi-Han;Eom, Yong-Kyoon
    • Proceedings of the KSME Conference
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    • 2001.06d
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    • pp.509-515
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    • 2001
  • In a square cavity, the flow phenomena in the surrounding of the bubble attached at the upper cooled solid wall were studied by using a thermo-sensitive liquid-crystal tracer and image processing techniques. This method offers the advantage of measuring the entire flow field in a selected plane within the fluid at a given instant of time in contrast to point by point method like T/C. Quantitative data of the temperature were obtained by applying a colour-image-processing to the. visualized image. As the growing of a bubble, In a bubble size appears the flow phenomena which the direction of flow is reversed in the entire temperature and flow field. The observed phenomena are described with regard to thermocapillary convection.

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A Study on the Explosionproof devices Installation in the Manufacturing Process (제조업체 방폭설비 적용에 관한 연구)

  • Song, Yong-Sig;Lee, Jun-Suk;Jeong, Hyun-Gyu;Cho, Won-Cheol;Lee, Tae-Shik
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.565-570
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    • 2007
  • The explosionproof apparatus is a devices that is enclosed in a case capable of withstanding an explosion of a specified gas or vapor that may occur within it and of preventing the ignition of a specified gas or vapor surrounding the enclosure by sparks, flashes, or explosion of the gas or vapor within, and that operates at such an external temperature that a surrounding flammable atmosphere will not be ignited thereby This kind of exeplosionfproof devices should be installed suitable for the characteristics of the space or process condition that should be protected to prevent explosion or fire. But, due to the lack of information and techniques on the explosionproof technology, some dangerous area is not properly protected from an explosion or it cost too much to implement the explosionproof devices. In this report, the basic guidelines and several case studies of explosionproof devices installation will be introduced to be of help to field safety engineer.

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The Value of High Resolution Ultrasonography in Diagnosis of Thyroid Nodule (갑상선 결절의 진단에 있어서 고해상능 초음파검사의 가치)

  • Shim Hyung-Jin;Choung Hue-Moon;Yoon Jung-Han;JeGal Young-Jong;Park Jin-Gyoon
    • Korean Journal of Head & Neck Oncology
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    • v.6 no.2
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    • pp.114-118
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    • 1990
  • A clinical study of 37 cases with thyroid nodules, which were treated by surgical excision and confirmed pathologically at the Department of Surgery, Chonnam National University Medical School, from Dec. 1988 to Feb. 1990, was conducted and following results were obtained in ultrasonographic evaluation of thyroid nodules. 1) The thyroid adenoma were showed well-defined margin, homogenous internal echo and surrounding Halo, but thyroid cancer were showed ill-defined margin, inhomogenous internal echo and no surrounding Halo. 2) The sensitivity of high resoution ultrasonography compared with pathologic diagnosis to thyroid cancer was 87.5%, specificity 94.1%, accuracy 88%, false positive 5.88%, and negative 12.5%.

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Ultrasonographic Changes of Acute Renal Failure Induced by Gentamicin in Dogs (개에서 겐타마이신으로 유발된 급성 신부전의 초음파상 변화)

  • 진경훈;정종태
    • Journal of Veterinary Clinics
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    • v.18 no.1
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    • pp.35-43
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    • 2001
  • Present study was undertaken in order to document early renal ultrasonographic changes of gentamicin nephrotoxicosis and to show the value of renal ultrasonography as a contributory means of early diagnosis of acute renal failure in dogs. The experimental design was a randomized complete block design with six treatments in two blocks (gentamicin-treated & saline-treated). Acute renal failure was induced by toxic dosage of gentamicin (30 mg/kg) and saline solution sham equivalent in volume to that of the toxic dosage of gentamicin (1.5-3ml). Subjective visualization of increased renal cortex was visible as homogenous echoes that were hypoechoic relative to the surrounding tissues, whereas the renal medulla was anechoic to slightly hypoechoic. After treatment, the renal cortex was hyperechoic relative to the surrounding tissue. Increased renal cortex echogenicity was associated with significant nephrotoxicosis and was superior to serum creatinine elevation in nephrotoxicosis detection. Urine GGT was superior to other clinicopathological data utilized in the diagnosis of nephrotoxicosis. Based on the above results, increased renal cortex echogenicity seemed to be of use in detecting of acute renal failure.

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A Numerical Study on Interaction and Combustion of Droplets Injected into a Combustor (연소실에 분사된 액적 간의 상호작용과 연소현상에 대한 수치적 연구)

  • Kook, J.J.;Park, S.H.
    • Journal of the Korean Society of Combustion
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    • v.4 no.1
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    • pp.17-26
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    • 1999
  • Vaporization, ignition and combustion of fuel droplets in tandem array are theoretically investigated to understand the droplet interactions in combustors. Including the effects of density variation in gas-phase, internal circulation and transient liquid heating, a numerical studies are performed by changing parameters such as initial droplet temperatures, initial droplet spacings, initial Reynolds numbers, surrounding gas temperatures, and activation energies of fuel vapors. Combustion regime maps classify the droplet combustion phenomena according to the configuration and location of the flame with respect to injection Reynolds numbers and surrounding gas temperatures. In addition, it is shown that the dynamic histories of droplets and ignition delay times are dependent on droplet size ratios and initial spacings of tandem droplets.

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Estimation of Sea Surface Temperature Change by Tide Embankment Construction

  • Shin Dong-hoon;Lee Kyoo-seock
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.146-148
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    • 2005
  • This study investigates to detect sea surface temperature (SST) and land cover change after tide embankment construction using Landsat Thematic Mapper (TM) thermal infrared (TIR) band data at Shihwa Lake and surrounding area. SST measurement is important for studies of both the structure of the ocean and as the thermal boundary between the ocean and the atmosphere. The TIR band of TM images can be used to detect SST change whose shoreline is complicated and narrow like the study site. The purpose of this study is to estimate SST and land cover change at Shihwa Lake and surrounding area.

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A Study on the Quantifying of Rural Landscape Picture by Fractal Index (프랙탈 지수를 이용한 농촌 경관사진의 정량화 방안 연구)

  • Jeong, Ho-Hyun;Jung, Nam-Su
    • Journal of Korean Society of Rural Planning
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    • v.16 no.3
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    • pp.11-17
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    • 2010
  • With international attention to the rural landscape, there have been landscape management and conservation efforts. Because it contains characteristics of rural area, rural landscape has been recognized as an important component of rurality. With rural amenity resources survey projects launched since 2005, rural landscape categorization and evaluation such as resource value, use value, beauty, originality, traditionality, maintenance are performed by expert questionnaire survey and 100 rural amenity resources are selected. In this study, we performed fractal analysis for developing evaluation system of the rural landscape photographs. In evaluating processes, main and surrounding landscape are separated and fractal indexes are calculated and analyzed with beauty value scoured by experts. Results show that beauty value is not significantly related with fractal index but differences of main and surrounding landscape fractal index.

Analysis of accidents due to Urban Ground Excavation (지반굴착공사로 인한 사고사례 분석)

  • Seong, Joo-Hyun;Yoon, Jong-Ku;Jung, Soo-Hyung
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09a
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    • pp.1087-1094
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    • 2010
  • With recent growth of population and industry, urban development grows into grand scheme of excavation and construction in urban area. As the development progress advanced, the developments get large and deepen. With a progress of technology development in geotechnical engineering in Korea, most our grand scheme of projects follows great progress. On the other hand, some excavation in construction site caused direct or indirect event that affects the adjacent or surrounding structures by excavation from time to time. This event usually happens around residential and commercial area where underground tunnel, subway station, commercial building, and high-rises excavation site is, could lead great damage on economy as well as personal injury or human casualties. In order to prevent this event, the study has to be done with analysis on various events of excavation and its cause. In this paper, the research has collected the various excavation events and their causes to analyze on each site and event to define emphasis on surrounding environment.

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