• Title/Summary/Keyword: 3DOM

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Dynamic Response Analysis of Tension Leg Platforms in Multi-directional Irregular Waves (Frequency Domain Analysis) (다방향 불규칙파중의 TLP의 동적응답해석 (주파수영역 해석))

  • 구자삼;조효제;이창호
    • Journal of Ocean Engineering and Technology
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    • v.8 no.1
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    • pp.23-32
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    • 1994
  • A numerical procedure is described for simultaneously predicting the motion and structural responses of tension leg platforms (TLPs) in multi-directional irregular waves. The developed numerical approach is based on a combination of a three dimensional source distribution method, the finite element method for structurally treating the space frame elements and a spectral analysis technique of directional waves. The spectral description for the linear responses of a structure in the frequency domain is sufficient to completely define the responses. This is because both the wave inputs and the responses are stationary Gaussian ran dom process of which the statistical properties in the amplitude domain are well known. The hydrodynamic interactions among TLP members, such as columns and pontoons, are included in the motion and structural analysis. The effect of wave directionality has been pointed out on the first order motion, tether forces and structural responses of a TLP in multi-directional irregular waves.

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Effects of $CO_2$ and $H_2O$ Additions on Partially Premixed Counterflow Flame by Considering Nongray Gas Radiation (비회색 가스 복사를 고려한 층류대향류 부분예혼합 화염에서의 $CO_2$$H_2O$ 첨가에 따른 영향 연구)

  • Jo, Bum-Jin;Kim, Tae-Kuk
    • Journal of the Korean Society of Combustion
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    • v.10 no.3
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    • pp.10-16
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    • 2005
  • Detailed flame structures of the counterflow flames of $CH_4/Air$ formed with $CO_2$ and $H_2O$ addition are studied numerically. The detailed chemical reactions are modeled by using the OPPDIF and CHEMKIN-II code. Only the $CO_2$ and $H_2O$ are assumed to participate in radiative heat transfer while all other gases are assumed to be transparent. The discrete ordinates method(DOM) and the narrow band based WSGGM with a gray gas regrouping technique(WSGGM-RG) are applied for modeling the radiative transfer through non-homogeneous and non-isothermal combustion gas mixtures generated by the counter flow flames. The results compared with the SNB model show that the WSGGM-RG is successful in modeling the counterflow flames with non-gray gas mixture. The numerical results show that the addition of $CO_2$ and $H_2O$ to the oxidant nozzle lowers the peak temperature and the NO concentration in flame.

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ESTIMATION OF IOP FROM INVERSION OF REMOTE SENSING REFLECTANCE MODEL USING IN-SITU OCEAN OPTICAL DATA IN THE SEAWATER AROUND THE KOREA PENINSULA

  • Moon, Jeong-Eon;Ahn, Yu-Hwan;Ryu, Joo-Hyung;Yang, Chan-Su
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.224-227
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    • 2006
  • For estimation of three inherent optical properties (IOPs), the absorption coefficients for phytoplankton ($a_{ph}$) and suspended solid particle ($a_{ss}$) and dissolved organic matter ($a_{dom}$), from ocean reflectance, we used inversion of remote sensing reflectance model (Ahn et al., 2001) at this study. The IOP inversion model assumes that (1) the relationship between remote sensing reflectance ($R_{rs}$) and absorption (a) and backscattering ($b_{b}$) is well known, (2) the optical coefficients for pure water ($a_{w}$, $b_{bw}$) are known, (3) the spectral shapes of the specific absorption coefficients for phytoplankton ($a^*_{ph}$) and suspended solid particle ($a^*_{ss}$) and the specific backscattering coefficients for phytoplankton ($b_b^*_{ph}$) and suspended solid particle ($b_b^*_{ss}$) are known. The input data of IOP inversion model is used in-situ ocean optical data at the seawater around the Korea Peninsula for 5 years (2001-2005). We compared the output data of the IOP inversion model and the in-situ observation for seawater around the Korea Peninsula.

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Seismic Response Analysis of Dam-Reservoir System Using Transmitting Boundary (전달경계를 이용한 댐-호소 계의 지진응답해석)

  • 조정래
    • Journal of the Earthquake Engineering Society of Korea
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    • v.3 no.1
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    • pp.123-132
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    • 1999
  • One of the major difficulties in the seismic analysis of a dam-reservoir system is the treatment of the energy radiation in the upstream direction of the reservoir. In the paper, a new transmitting boundary is presented that can model properly the radiation of energy in the far field direction of a semi-infinite reservoir with constant depth. In the newly developed method, effects of surface wave motion are taken into accounted and the reservoir-foundation interaction is approximately accounted for with an absorbing boundary condition. If a dam has vertical upstream face and the infinitely long reservoir maintains constant depth, then the proposed transmitting boundary can be directly coupled with the model of dam body. In present study, the dam body is assumed to behave elastically and modeled by finite element method. Seismic responses of a dam model are investigated using the newly developed transmitting boundary.

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First Record of the Banded Sergeant, Abudefduf septemfasciatus (Perciformes: Pomacentridae) from Jeju Island, Korea (한국산 자리돔과 (Pomacentridae) 어류 1미기록종, Abudefduf septemfasciatus)

  • Kwun, Hyuck Joon;Park, Jinsoon;Kim, Hye Seon;Bae, Hanna
    • Korean Journal of Ichthyology
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    • v.28 no.1
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    • pp.47-51
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    • 2016
  • Three specimens of Abudefduf septemfasciatus were collected firstly from tidal pools on the southern and northern coasts of Jeju Island, Korea in August 2015. This species is characterized by black blotches on the upper origin of the pectoral fin, upper caudal peduncle and a dorsal fin between the second and fourth spines, predorsal scales beyond to above the middle of the eye, 12~13 soft dorsal and anal fin rays, and 20 lateral-line scales. This species is distinguishable from Abudefduf sordidus by soft dorsal and anal fin rays, location of caudal peduncle blotch, and location of the dorsal fin blotch. The newly proposed Korean name is "Il-gop-jul-ja-dom".

New Record of the Black-Velvet Angelfish, Chaetodontoplus melanosoma (Pomacanthidae, Perciformes) from Korea (한국 제주도에서 채집된 청줄돔과 어류 1미기록종, Chaetodontoplus melanosoma)

  • Han, Song Hun;Kim, Maeng Jin;Song, Choon Bok
    • Korean Journal of Ichthyology
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    • v.27 no.3
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    • pp.249-252
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    • 2015
  • This is the first report of Chaetodontoplus melanosoma, belonging to the family Pomacanthidae, collected in Korea. The specimen (123.1 mm in standard length) was caught in the coastal waters of Jejudo Island by a trammel net on 23 February 2010. This species was characterized by the following morphological traits: 26 dorsal fin rays, 16 pectoral fin rays, 6 pelvic fin, 21 anal fin rays, no blue strips on the body, no markings behind the eye, and an egg-shaped faint black spot on the base of the pectoral fin. We suggest a new Korean name "Geom-eun-cheong-jul-dom" for C. melanosoma.

A Study on the Activation of the Fur Fashion Industry in Korea(Focused on the opening domestic Fur Market after 1988) (한국 모피 패션 산업 활성화에 관한 연구 -'88년 모피 내수시장 개방 이후를 중심으로-)

  • 정성혜
    • Journal of the Korean Society of Costume
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    • v.22
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    • pp.45-60
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    • 1994
  • Since 1988 the fur fashion industry in Korea has been difficult in exporting and competition with too many brands after opening the dom-estic fur market. However comparing with the interest of manufactures and consumers there are few of related references and books. So the purpose of this study is to put in order and summurize the manufacture in fur cloth-ing the informations of domestic and oversea fur markets and the other professional references. After all it is to help succeed in domestic and international fur markets and give the new ideas of designing and merchandising to the fur fashion industry. The results were as follows: 1. Contact with fur specialty stores in the international fashion cities and tourist cities directly. 2. Establish oversea factories in the low labor countries. 3. Exploit and invest in Russia china and the East European countries for suppliment of law materials and fur market. 4. Need the market research and promotion for encroachment in Japanese fur market. 5. Create the original brands with inter-national fashion sense. 6. Develop the manufacture line for diverse models in small lots matching with the modern life styles. 7. Need the fashion show exhibition pro-motion with reasonable prices and creative new designing with various color trimming texturizing and combination with the other materials. 8 Subdivide and distinguish labels into different types for avoiding with too much com-petition and comvenience of consumers. 9. Make an effort to weaken the black mar-ket the 30% of the domestic fur market.

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BIM and Thermographic Sensing: Reflecting the As-is Building Condition in Energy Analysis

  • Ham, Youngjib;Golparvar-Fard, Mani
    • Journal of Construction Engineering and Project Management
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    • v.5 no.4
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    • pp.16-22
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    • 2015
  • This paper presents an automated computer vision-based system to update BIM data by leveraging multi-modal visual data collected from existing buildings under inspection. Currently, visual inspections are conducted for building envelopes or mechanical systems, and auditors analyze energy-related contextual information to examine if their performance is maintained as expected by the design. By translating 3D surface thermal profiles into energy performance metrics such as actual R-values at point-level and by mapping such properties to the associated BIM elements using XML Document Object Model (DOM), the proposed method shortens the energy performance modeling gap between the architectural information in the as-designed BIM and the as-is building condition, which improve the reliability of building energy analysis. Several case studies were conducted to experimentally evaluate their impact on BIM-based energy analysis to calculate energy load. The experimental results on existing buildings show that (1) the point-level thermography-based thermal resistance measurement can be automatically matched with the associated BIM elements; and (2) their corresponding thermal properties are automatically updated in gbXML schema. This paper provides practitioners with insight to uncover the fundamentals of how multi-modal visual data can be used to improve the accuracy of building energy modeling for retrofit analysis. Open research challenges and lessons learned from real-world case studies are discussed in detail.

Adaptive Mode Switching in Correlated Multiple Antenna Cellular Networks

  • Lee, Chul-Han;Chae, Chan-Byoung;Vishwanath, Sriram;Heath, Jr., Robert W.
    • Journal of Communications and Networks
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    • v.11 no.3
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    • pp.279-286
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    • 2009
  • This paper proposes an adaptive mode switching algorithm between two strategies in multiple antenna cellular networks:A single-user mode and a multi-user mode for the broadcast channel. If full channel state information is available at the base station, it is known that a multi user transmission strategy would outperform all single-user transmission strategies. In the absence of full side information, it is unclear what the capacity achieving method is, and thus there are few criteria to decide which of the myriad possible methods performs best given a system configuration. We compare a single user transmission and a multi user transmission with linear receivers in this paper where the transmitter and the receivers have multiple antennas, and find that neither strategy dom inates the other. There is instead a transition point between the two strategies. Then, the mode switching point is determined both ana lytically and numerically for a multiple antenna cellular downlink with correlation between transmit antennas.

Updating BIM: Reflecting Thermographic Sensing in BIM-based Building Energy Analysis

  • Ham, Youngjib;Golparvar-Fard, Mani
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.532-536
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    • 2015
  • This paper presents an automated computer vision-based system to update BIM data by leveraging multi-modal visual data collected from existing buildings under inspection. Currently, visual inspections are conducted for building envelopes or mechanical systems, and auditors analyze energy-related contextual information to examine if their performance is maintained as expected by the design. By translating 3D surface thermal profiles into energy performance metrics such as actual R-values at point-level and by mapping such properties to the associated BIM elements using XML Document Object Model (DOM), the proposed method shortens the energy performance modeling gap between the architectural information in the as-designed BIM and the as-is building condition, which improve the reliability of building energy analysis. The experimental results on existing buildings show that (1) the point-level thermography-based thermal resistance measurement can be automatically matched with the associated BIM elements; and (2) their corresponding thermal properties are automatically updated in gbXML schema. This paper provides practitioners with insight to uncover the fundamentals of how multi-modal visual data can be used to improve the accuracy of building energy modeling for retrofit analysis. Open research challenges and lessons learned from real-world case studies are discussed in detail.

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