• Title/Summary/Keyword: divers

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ON DIVERSITY OF CERTAIN t-INTERSECTING FAMILIES

  • Ku, Cheng Yeaw;Wong, Kok Bin
    • Bulletin of the Korean Mathematical Society
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    • v.57 no.4
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    • pp.815-829
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    • 2020
  • Let [n] = {1, 2, …, n} and 2[n] be the set of all subsets of [n]. For a family 𝓕 ⊆ 2[n], its diversity, denoted by div(𝓕), is defined to be $$div(\mathcal{F})=\min_{x{\in}[n]}\{{\mid}{\mathcal{F}}(\bar{x}){\mid}\}$$, where ${\mathcal{F}}(\bar{x})=\{F{\in}{\mathcal{F}}:x{\not\in}F\}$. Basically, div(𝓕) measures how far 𝓕 is from a trivial intersecting family, which is called a star. In this paper, we consider a generalization of diversity for t-intersecting family.

Carbon Containing Compositions

  • Mansurova, R.M.;Mansurov, Z.A.;Soh, Deawha
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.335-338
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    • 2001
  • With the use of the electron microscopy and X-ray phase analysis the regularities of carbon deposit formation in process of methane and propane pyrolysis on the zeolites, Kazakhstan natural clays, chrome and bauxite sludge containing metal oxides of iron subgroup, have been studied. In process of over-carbonization the trivalent iron was reduced to metal form. In addition, the carbon tubes of divers morphology had been impregnated with ultra-dispersed metal particles. The kinetic parameters of carbon formation in process of methane decomposition on the zeolite CoO mixture surface were investigated by method of thermo-gravimetric analysis. The morphology and structure of formed carbon fibrils, with the metal particles fixed at their ends, have been investigated, the formation of branched carbon fibrils pattern, so called octopus, being found.

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SHS of Oxide Systems Based on MCR of Quartz Modified by Organometallic Compounds

  • Soh, Dea-Wha;Tlek, Ketegenov;Z.A., Mansurov
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.666-669
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    • 2002
  • The differences of the effects of mechanical substance pre-activation in the mills with divers force effect schemes on the self-propagating high temperature synthesis (SHS) of the $SiO_2$ + 37.5% Al system were investigated. The power saturation of activated material state are estimated referring on the variations of dilatometry curve paths. The effects of activation time on the temperature of sample self-ignited in the furnace, combustion temperature and completeness of the quartz reaction with aluminium were determined. The enhancing effects of organic modifiers of quartz particle surfaces on the further SHS synthesis development were shown.

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A Study on the Axis Used for Interior Spaces of Peter Eisenman Architecture (피터아이젠만 건축의 실내 공간에 사용된 축에 관한 연구)

  • Lee, Jong-Ran
    • Journal of The Korean Digital Architecture Interior Association
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    • v.11 no.4
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    • pp.39-46
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    • 2011
  • This Study is about the Axis used for creating forms of interior spaces in representative works of Peter Eisenman architecture. The plans, elevations, photos of interior spaces of his architecture were collected and analysed. In conclusion, the methods using axises were classified in the axises crossing right angle and the rotating axises crossing right angle. The rotating axis were divided into one-angle rotating and multi-angle rotating. The axises were rotated on the plan or rotated on the elevation. The axises crossing right angle were used for dividing, assembling, transforming and composing different proportions of rectangles in interior spaces. The rotating axises crossing right angle were used for creating divers forms such as triangle, quadrilateral, and polygon. The one-angle rotating emphasizes directions of axises in interior spaces. The multi-angle rotating emphasizes decentered directions in interior spaces. The parts created while crossing axises three-dimensionally were opened or filled. The axises were used dynamically and three-dimensionally for diversity of forms in interior spaces of Peter Eisenman architecture.

Development of Cleaning Module and Operating System of Underwater Robot for Ship Hull Cleaning (선저 청소용 수중로봇의 청소 모듈 및 제어 시스템 개발)

  • Choi, Hyeung-Sik;Kwon, Kyoung-Youb;Chung, Koo-Rack;Seo, Joo-No;Kang, Hyung-Suk
    • Journal of Advanced Marine Engineering and Technology
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    • v.33 no.4
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    • pp.553-561
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    • 2009
  • This paper presents development of ROV-type underwater robot capable of cleaning ship hull in automatic mode. The purpose of developing this robot is for underwater cleaning to secure the safety of divers who inspect and clean the ship hull. The robot consists of the cleaning system with rotating brush mechanism, a car-like driving mechanism, inspection system using video, and overall control system for underwater communication and operation. In this paper, we present overall design process of the cleaning system and operating system and technical contents of the overall control system for the underwater cleaning robot.

CAD/CAM System development for Stereolitihography (광조형용 CAD/CAM 시스템 개발)

  • 홍삼열;김준안;반갑수;백인환
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.04a
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    • pp.592-596
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    • 1996
  • The CAD/CAM System oriented to StereoLithographic Rapid Prototyping was constructed and developed. The software architecture uses a 586PC running the windows NT operating system. An .STL file brought into the software program can be verified in divers view points and focused for a detail of concern. A variety of Entity was applied to define an array of triangular facets and sliced loops. The system provides Edit, Scale, Orient, Copy and Divide commands to modify .STL model. The NC codes are created according to various laser beam scan pattern and the software show the parts on the platform before they are constructed. This system is written in Visual C and has been proved as a powerful tool for producing solid parts directly from a CAD modelling, using actual applications.

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The Acoustic Characteristics in Women Diver's Soombijil Sound (해녀의 숨비질소리에 대한 음향특징)

  • Han, Ji-Yeon;Park, Hyun-Ja;Jeong, Ok-Ran
    • Proceedings of the KSPS conference
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    • 2007.05a
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    • pp.176-179
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    • 2007
  • This study examined the acoustic characteristics in women diver's Soombijil sound. A total of 18 women divers was attended this study. Acoustic analysis was performed via Praat. Soombijil sound were classified into three types as pitch variations in beginning, middle, and ending part. Type I showed increasing-decreasing-flat. Type II was identified by the shape of flat-flat-increasing. The shape of type III showed increasing-decreasing-increasing. Duration of Soombijil sound was mean 1.48 sec. The range of frequency was 1591.54 ${\sim}$ 4477.13 Hz. FFT analysis showed that frequencies were concentrated 500${\sim}$2000 Hz. Type I and II showed two peaks at 500 Hz and 1500${\sim}$2000 Hz. Type III has one peak below 500 Hz.

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A Study on the Actual Status and Needs of Leisure of Middle Age (여가활성화 방안 모색을 위한 여가실태 및 요구에 관한 연구 - 중년층을 대상으로 -)

  • Shin, Hwa-Kyoung;Lee, Joon-Min
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2004.11a
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    • pp.207-212
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    • 2004
  • The propose of this study is to grasp actual status and needs of leisure of middle age. The questionnaire survey is used, the subjects are middle age from 40${\sim}$50's living in big city. The questionnaire consists of leisure, leisure actual condition, leisure satisfaction and need. Frequency, percent, average, x2-test, t-test and ANOVA are used for data analysis. The results of this study are as following; First, leisure is necessary to elevate Quality of life in terms of spiritual , psychological stability and physical health. Second, subjects have more leisure time in weekend the characteristics of leisure time are scattered in woman. Third, in the future the subjects wish to have leisure with family. Therefore, it is necessary to develop leisure program and facilities to promote family leisure. Fourth, the subjects are not satisfied with current leisure for unsufficiency of leisure time, cost, facility and program. Fifth, present leisure behavior characteristics are restrictive and passive. In the near future, however, they showed desire to engage in divers forms of leisure including active and participant leisure.

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Salvage System Using Location Based Services

  • Kwon, Seong-Geun;Kim, Haesoo
    • Journal of Korea Multimedia Society
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    • v.18 no.12
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    • pp.1427-1431
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    • 2015
  • In the salvage area, the location of the incident vessel and diver to rescue the victim are very important. But there are no ways but to rely on the GPS satellites to obtain the location in the salvage sites. Because the positioning using GPS satellites has a measurement error of up to 50 meters caused by the status of the atmosphere, a new positioning method with more accuracy should be devised. So if studies on measuring the position of the ships and divers accurately in the sea are performed, it will be helpful in the field of the salvage positioning. In this paper, a high precision positioning system in salvage using DGPS signal through mobile broadcasting is proposed with positioning error of up to 1 meter.

Carbon Containing Compositions

  • Mansurova, R.M.;Mansurov, Z.A.
    • Transactions on Electrical and Electronic Materials
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    • v.2 no.2
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    • pp.5-15
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    • 2001
  • The experiment established optimal conditions for over-carbonization. With the use of the electron microscopy and X-ray phase analysis the regularities of carbon deposit formation in process of methane and propane pyrolysis on the zeolites, Kazakhstan natural clays, chrome and bauxite sludge containing metal oxides of iron subgroup, have been studied. In process of over-carbonization the trivalent iron was reduced to metal form. In addition, the carbon tubes of divers morphology had been impregnated with ultra-dispersed metal particles. The kinetic parameters of carbon formation in process of methane decomposition on the zeolite - CoO mixture surface were investigated by method of thermo-gravimetric analysis. The morphology and structure of formed carbon fibrils, with the metal particles fixed at their ends, have been investigated, the formation of branched carbon fibrils pattern, so called octopus, being found. Also, the walnut shells and grape kernel carbonization, their immobilization by the cells of selective absorption of heavy metal and sulfur dioxide ions have been studied. The example of metal-carbon composites used as adsorbents for wastewater purification, C$_3$- C$_4$ hydrocarbon cracking catalysts and refractory materials with improved properties have been considered.

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