• Title/Summary/Keyword: pit

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The Wave Diffraction in a Partial-Reflecting Harbor due to Submarine Pit (Pit에 의한 부분반사율을 갖는 항내에서의 파랑 회절에 관한 연구)

  • Kim, Sung-Duk;Lee, Hong-Sik
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.19 no.5
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    • pp.502-510
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    • 2007
  • The present study is to estimate the effect of diffracted wave fields inside a harbor, around harbor entrance and outer breakwater, when a navigation channel is dredged in the vicinity of the a harbor entrance. The wave field of the problem is considered to be two-dimensional plane and the configuration of the submarine pit on the sea bed is designated by a single rectangular type. The numerical simulation is performed by using the solution of the Greet function based on the boundary integral equation. The results of this study is illustrated by applying the normal incidence and partially reflecting boundaries.

The Possibility on Utilization of Underground Pit for Reduction of Cooling and Heating Load (냉방과 난방 부하 감소를 위한 지하피트의 이용 가능성)

  • Cho Sung-Woo
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.18 no.2
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    • pp.144-150
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    • 2006
  • The purpose of this study is to predict outlet temperature and humidity through underground pit for the reduction of cooling load and heating load. Commonly, the underground temperature is lower than outdoor in summer but the reverse happens in winter. When the outdoor average air temperature is $25.7^{\circ}C$ during cooling periods, the average outlet air temperature through underground pit is $23.6^{\circ}C$ with 3 m-depth and 60m-length and is $22.2^{\circ}C$ with 3 m-depth and 150 m-length. When the outdoor average air temperature is $4.9^{\circ}C$ during heating periods, the average outlet air temperature through underground pit is $7.7^{\circ}C$ with 3m-depth and 60 m-length and is $10.8^{\circ}C$ with 3 m-depth and 150 m-length. The outlet air temperature is affected by more length than depth of underground pit. The diffusion ratio of outdoor humidity is $-7.7\times10^{-8}kg/s$ in cooling periods and $9.29\times10^{-7}kg/s$ in heating periods.

Thermal Behavior of Flow Pattern Defect and Large Pit in Czochralski Silicon Crystals and Effects of Large Pit upon Device Yield (쵸크랄스키 Silicon 단결정의 Large Pit과 Flow Pattern defect의 열적 거동과 Large Pit의 소자 수율에의 영향)

  • Song, Yeong-Min;Mun, Yeong-Hui;Kim, Jong-O;Jo, Gi-Hyeon
    • Korean Journal of Materials Research
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    • v.11 no.9
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    • pp.781-785
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    • 2001
  • The thermal behavior of Flow Pattern Defect (FPD) and Large Pit (LP) in Czochralski Silicon crystal was investigated by applying high temperature annealing ($\geq$$1100^{\circ}C$) and non-agitated Secco etching. For evaluation of the effect of LP upon device performance/yield, commercial DRAM and ASIC devices were fabricated. The results indicated that high temperature annealing generates LPs whereas it decreases FPD density drastically. However, the origins of FPD and LP seemed to be quite different by not showing any correspondence to their density and the location of LP generation and FPD extinction. By not showing any difference between the performance/yield of devices whose design rule is larger than 0.35 $\mu\textrm{m}$, LP seemed not to have detrimental effects on the performance/yield.

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Effectiveness Assessment on the Soil Temperature of KMA as Ground Heat Source Using CFD in Pit Area (CFD를 이용한 기상청 지중온도의 피트부분 지중열원 유용성 평가에 관한 연구)

  • Min, Joon Ki;Kim, Jeong Tai
    • KIEAE Journal
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    • v.8 no.5
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    • pp.49-54
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    • 2008
  • The experimental of temperature, humidity and velocity was taken from the underground pit which utilized the system of ground heat source quite similar to the cool-pit system. Also, through CFD analysis, one could review the effectiveness of analysis of future alternatives. Furthermore, the temperature range of mock up cool-pit system was analyzed by inputting the weather data of annual average soil temperature provided by KMA(Korea Meteorological Administration) into the fluid simulation of anticipated heat distribution. Firstly, the difference between the temperature of air exhaust of the pit or the temperature of air supply of the compressor room and the experimental data for the month of May from the CFD analysis came out to be $0.6^{\circ}C$ and $0.9^{\circ}C$ respectively with tolerance of 3.1% and 4.7%. Secondly, the difference between the temperature of air exhaust of the Pit or the temperature of air supply of the compressor room and the experimental data for the month of July from the CFD analysis came out to be $0.8^{\circ}C$ and $1.1^{\circ}C$ respectively with tolerance of 3.3% and 4.5%. Thirdly, for the month of May, the difference between the experimental data taken for the air exhaust of the Pit or the air supply of the compressor room and soil temperature provided by KMA for monthly and yearly average temperature of Jeonju region came out be $1.9^{\circ}C$ and $1.8^{\circ}C$ respectively with tolerance of 10.7% and 9.8%. Fourthly, for the month of July, the difference between the experimental data taken for the air exhaust of the Pit or the air supply of the compressor room and soil temperature provided by KMA for monthly and yearly average temperature of Jeonju region came out be $1.1^{\circ}C$ and $1.4^{\circ}C$ respectively with tolerance of 4.5% and 5.8%. The result of above experiments allowed us to establish CFD model set up as a verification tool that is based on experimental data collected within the Pit area. Also, one could confirm the possibility to apply weather data of soil temperature provided by KMA in order to anticipate proper value for CFD analysis.

Priority based Image Transmission Technique with DPCM in Wireless Multimedia (무선 멀티미디어 센서 네트워크에서 예측부호화를 통한 우선순위 기반 이미지 전송 기법)

  • Lee, Joa-Hyoung;Jung, In-Bum
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.4
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    • pp.1023-1031
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    • 2010
  • With recent advances in hardware and wireless communication techniques, wireless multimedia sensor network which collects multimedia data through wireless sensor network has started to receive a lot of attentions from many researchers. Wireless multimedia sensor network requires a research of efficient compression and transmission to process the multimedia data which has large size, in the wireless sensor network that has very low network bandwidth. In this paper, we propose PIT protocol for the transmission based on the priority that classified by the DPCM compression. The PIT protocol sets different priority to the each subbands which are divided by the wavelet transform. The PIT protocol transmits the data with higher priority to guarantee the high image quality. The PIT protocol uses the characteristic of wavelet transform that the transformed image is very insensible to the data loss. In PIT protocol, each subbands of wavelet transformed image has fair weight in the compressed image to utilize the prioriy based transmission. The experiment results show that the PIT protocol improves the quality of image in spite of data loss.

Study on Optimization and Skin Permeation of PIT Nanoemulsion Containing α-Bisabolol (α-Bisabolol을 함유한 PIT Nanoemulsion의 최적화 및 피부흡수연구)

  • Kim, HuiJu;Yoon, Kyung-Sup
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.6
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    • pp.1738-1751
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    • 2020
  • The skin is divided into three parts: the epidermis, the dermis, and the subcutaneous fat, and the stratum corneum, which is located at the top of the epidermis, acts as a barrier that prevents drug delivery. Nanoemulsions are known to be effective in transdermal delivery of drugs through intercellular lipids because of their unique small particle size. In this study, phase inversion temperature (PIT) nanoemulsion containing α-bisabolol was optimized using response surface methodology (RSM) for effective skin absorption of α-bisabolol. As a preliminary experiment, the 25-2 fractional factorial design method and the 23 full factorial design method were performed. Box-Behnken design was performed based on the results of the factorial design method. The content of surfactant (6.3~12.6%), co-surfactant (5.2~7.8%) and α-bisabolol (0.5~5.0%) were used as factors, and the dependent variable was the particle size of the nanoemulsion. PIT nanoemulsion optimization was performed according to the RSM results, and as a result, the optimal nanoemulsion formulation conditions were predicted to be 10.4% surfactant content, 6.3% co-surfactant content, and 5.0% α-bisabolol content. As a result of the skin absorption test, the final skin absorption rate of the PIT nanoemulsion was 35.11±1.01%, and the final skin absorption rate of the general emulsion as a control was 28.25±1.69%, confirming that the skin absorption rate of the PIT nanoemulsion was better.

Identification and Analysis of PIT1 Polymorphisms and Its Association with Growth and Carcass Traits in Korean Cattles (Hanwoo) (한우에서 Pituitary-specific Transcription Factor (PIT1) 유전자와 경제 형질과의 연관성 분석)

  • Choi, J.R.;Oh, J.D.;Cho, K.J.;Lee, J.H.;Kong, H.S.;Lee, H.K.
    • Journal of Embryo Transfer
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    • v.22 no.3
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    • pp.167-172
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    • 2007
  • Pituitary-specific transcription factor (PIT1) 유전자는 동물의 성장을 조절하고 근육 형성에 관여하는 유전자로서 최근에는 단일염기다형성 변이가 한우를 비롯한 동물에서 관찰되었으며, 한우의 경제 형질과 연관성이 보고되었다. 본 연구는 PIT1 유전자의 단일염기다형성 변이가 한우에서 성장 인자에 미치는 영향과 경제 형질에 대한 유전자형간 육종가와의 상관성에 대해 알아보고자 하였다. 도체 성적을 보유하고 있는 한우 후보종모우 집단 268두를 대상으로 PIT1 유전자 A1256G 다형성을 조사하여 유전자형의 빈도를 분석하였고 각각의 유전형에 따른 기본적인 검정 성적을 바탕으로 경제 형질과의 연관성을 비교 분석하였다. 268두의 한우에서 PIT1 유전자의 A1256G 유전자형 빈도는 MseI 제한 효소를 사용했을 때 A 유전자 빈도(0.37)보다 G 유전자 빈도(0.62)가 높게 나타났다. 통계적 분석을 통하여 각 유전자형에 대한 경제 형질과의 관련성을 분석한 결과, 각 유전자형 간에 12개월령 체중 (body weight 12, BW12)에서 유의한 차이를 보였고, 등지방 두께 육종가 (Backfat thickness-estimated breeding value, BF-EBV)와도 유의한 차이가 있었지만 (p<0.05), marbling score (MS), carcass weight (CW), M. longissimus dorsi area (LDA) 등 다른 경제 형질과는 통계학적으로 유의한 차이가 없었다. PIT1 유전자의 A1256G 다형성은 한우의 성장과 도체체중에 관여하는 인자로 작용하는 것으로 보여진다.

Effect of Racetrack Pit Depth and Bulk Stress on Far and Near-side Magnetic Flux Leakage at Ferromagnetic Pipeline (강자성 배관 외.내부 벽의 racetrack형 결함깊이와 부피응력이 누설자속에 미치는 영향)

  • Ryu, K.S.;Park, Y.T.;Son, D.;Atherton, D.L.;Clapham, L.
    • Journal of the Korean Magnetics Society
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    • v.13 no.2
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    • pp.70-75
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    • 2003
  • Non-linear anisotropic materials were used to simulate the effects of bulk tensile stress in 3D finite element analysis (FEA). FEA was used to calculate the effects of near and far-side racetrack pit depth and simulated bulk tensile stress on magnetic flux leakage (MFL) signals. The axial and radial MFL signals were depended on near and far-side racetrack pit depth and on the bulk stress, but the circumferential MFL signal was not depended on them. The axial and radial MFL signals increased with greater pit depth and applied bulk stress, but the circumferential MFL signal was scarcely changed.

Association of polymorphisms in Pit-1 gene with growth and feed efficiency in meat-type chickens

  • Jin, Sihua;He, Tingting;Yang, Lei;Tong, Yucui;Chen, Xingyong;Geng, Zhaoyu
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.11
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    • pp.1685-1690
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    • 2018
  • Objective: The pituitary specific transcription factor-1 (Pit-1) gene is responsible for pituitary development and growth hormone expression and is regarded as a pivotal candidate gene for growth and production in chickens. Therefore, the aim of this study was to investigate the association of Pit-1 polymorphisms with growth and feed efficiency traits in yellow meat-type chickens. Methods: In the present study, five single nucleotide polymorphisms (SNPs) of Pit-1 were selected and genotyped by high-throughput matrix-assisted laser desorption-ionization time-of-flight mass spectrometry in 724 meat-type chickens. Results: Association analysis showed that rs13687126 of Pit-1 was strongly associated with body weight gain (BWG) and feed intake (FI) (p<0.05), and that rs13687128 was significantly correlated with body weight at 70 days of age (BW70), BWG and feed conversion ratio (FCR) (p<0.05). SNP rs13905622 was strongly related to BW70 and FCR (p<0.05). Furthermore, birds with the GG genotype of rs13687126 had larger BWG and FI than those with the AG genotype (p<0.05). Individuals with the TT genotype of rs13687128 were significantly higher BW70 and BWG than those of the CT and CC genotype, while FCR was just the opposite (p<0.05). For rs13905622, the AA chickens showed strongly larger BW70 and lower FCR compared with the AT and TT chickens (p<0.05). Additionally, an ACA haplotype based on rs13687126, rs13687128, and rs13905622 had significant effects on BW70 and FCR (p<0.05). Conclusion: Our studies thus provide crucial evidence for the relationship between polymorphisms of Pit-1 and growth and feed efficiency traits which may be useful for meat-type chicken breeding programs.

Experimental Study on the Adjustment Processes of a Series of Mining Pits in the Dredged Channels (준설하천에서 직렬로 배열된 웅덩이의 적응에 관한 실험적 연구)

  • Jang, Chang-Lae;Lee, Gi-Ha
    • Korean Journal of Ecology and Environment
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    • v.44 no.4
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    • pp.385-395
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    • 2011
  • The adjustment processes and responses of a series of mining pits by sand or gravel mining were investigated by laboratory experiments. The filling processes of the two pits were affected by the bars developed in the upstream of the channel. However, the bars were not developed and the bed was degradated in the downstream of the pits due to little sediment flow, which was trapped in the pits. The submerged angle of repose in the pits was nearly constant when the pits were being filled. After the filling processes of the pits were finished, the pit was speedily filled with sediment, and the bed was aggradated and migrated with speed. However, the angle of repose decreased. As the distance between the upstream pit and the downstream pit increased, the bed of the pit downstream was tailcutted and degradated. The migration speed of the pit decreased. However, the dimensionless pit depth increased as the distance between the pits increased. The dimensionless pit depth increased with time.