• Title/Summary/Keyword: AT&T

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Characteristic of Nutrient Release by Submerged Plants under Different Water Temperatures in Lake Reservoir (호소저수구역에서 침수식물체의 수온별 영양염류 용출 특성)

  • Lim, Byung-Jin;Lee, Sang-Gyu;Seo, Dong-Cheol;Choi, Ik-Won;Kang, Se-Won;Seo, Young-Jin;Lee, Dong-Jin;Kim, Sang-Don;Heo, Jong-Soo;Cho, Ju-Sik
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.4
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    • pp.657-663
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    • 2012
  • To evaluate effects of water temperatures on nutrient releases of submerged plants in lake reservoir, COD, T-N and T-P releases of submerged plants were investigated for 60 days under different incubation temperatures ($5^{\circ}C$ and $25^{\circ}C$) in columns. The amounts of COD releases by Carex dimorpholepis were $60.4mg\;L^{-1}$ at $5^{\circ}C$ and $78.0mg\;L^{-1}$ at $25^{\circ}C$. In Miscanthus sacchariflorus, the amounts of COD releases were $62.5mg\;L^{-1}$ at $5^{\circ}C$ and $70.5mg\;L^{-1}$ at $25^{\circ}C$. The amounts of T-N releases in Carex dimorpholepis at $5^{\circ}C$ and $25^{\circ}C$ were 45.8 and $60mg\;L^{-1}$, respectively. In Miscanthus sacchariflorus, the amounts of T-N releases were $55.7mg\;L^{-1}$ at $5^{\circ}C$ and $61.0mg\;L^{-1}$ at $25^{\circ}C$. At $5^{\circ}C$, the amounts of T-P releases in Carex dimorpholepis and Miscanthus sacchariflorus were 5.65 and $7.10mg\;L^{-1}$, respectively. At $25^{\circ}C$, the amounts of T-P releases in Carex dimorpholepis and Miscanthus sacchariflorus were 8.70 and $8.18mg\;L^{-1}$, respectively. In the column experiment, the amounts of COD, T-N and T-P releases by submerged plants at $25^{\circ}C$ were generally higher than those at $5^{\circ}C$.

Growth of GaAs Crystals by synthesis Solute Diffusion Method (합성 용질 확산법에 의한 GaAs결정 성장에 관하여)

  • 문동찬;정홍배;이영희;김선태;최영복
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.41 no.1
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    • pp.56-62
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    • 1992
  • The GaAs bulk crystals are grown by the Synthesis Solute Diffusion(SSD) method and its properties are investigated. The crystal growth rate at optimum condition is 0.28 cm/day and their temperature dependence is R(T) = 2.92 x 10S04T exp(-1.548eV/kS1BTT) [cmS02T/day.K]. Etch pits density distribution along radial direction is order of 10S04TcmS0-2T and 10S03TcmS0-2T at the edge and middle of the wafers, respectively, and it increased exponentially along vertical direction of ingot. Moreover,it is uniformly distributed as order of 10S03TcmS0-2T in radial direction of In doped GaAs. The carrier concentration and mobilities are measured to 0.34-2.1 x 10S016T cmS0-3T and 2.3-3.3x10S03T cmS02T/V.sec, respectively.

THE GENERALIZED INVERSE ${A_{T,*}}^{(2)}$ AND ITS APPLICATIONS

  • Cao, Chong-Guang;Zhang, Xian
    • Journal of applied mathematics & informatics
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    • v.11 no.1_2
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    • pp.155-164
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    • 2003
  • The existence and representations of some generalized inverses, including ${A_{T,*}}^{(2)},\;{A_{T,*}}^{(1,2)},\;{A_{T,*}}^{(2,3)},\;{A_{*,S}}^{(2)},\;{A_{*,S}}^{(1,2)}\;and\;{A_{*,S}}^{(2,4)}$, are showed. As applications, the perturbation theory for the generalized inverse {A_{T,S}}^{(2)} and the perturbation bound for unique solution of the general restricted system $A_{x}$ = b(dim(AT)=dimT, $b{\in}AT$ and $x{\in}T$) are studied. Moreover, a characterization and representation of the generalized inverse ${A_{T,*}}^{(2)}$ is obtained.

SOLVABILITY FOR SECOND-ORDER BOUNDARY VALUE PROBLEM WITH INTEGRAL BOUNDARY CONDITIONS ON AN UNBOUNDED DOMAIN AT RESONANCE

  • Yang, Ai-Jun;Wang, Lisheng;Ge, Weigao
    • The Pure and Applied Mathematics
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    • v.17 no.1
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    • pp.39-49
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    • 2010
  • This paper deals with the second-order differential equation (p(t)x'(t))' + g(t)f(t, x(t), x'(t)) = 0, a.e. in (0, $\infty$) with the boundary conditions $$x(0)={\int}^{\infty}_0g(s)x(s)ds,\;{lim}\limits_{t{\rightarrow}{\infty}}p(t)x'(t)=0,$$ where $g\;{\in}\;L^1[0,{\infty})$ with g(t) > 0 on [0, $\infty$) and ${\int}^{\infty}_0g(s)ds\;=\;1$, f is a g-Carath$\acute{e}$odory function. By applying the coincidence degree theory, the existence of at least one solution is obtained.

Quantitative and Qualitative Evaluation of Brain Diffusion Weighted Magnetic Resonance Imaging: Comparision with 1.5 T and 3.0 T Units (뇌 확산강조 자기공명영상에 대한 정량적, 성적 평가: 1.5 T와 3.0 T 기기 비교)

  • Goo, Eun-Hoe;Dong, Kyung-Rae
    • Journal of Radiation Industry
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    • v.10 no.4
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    • pp.227-230
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    • 2016
  • DWI of biological effects are independent of magnetic field strength in various regions. High field strength, however, does affect the signal to noise ratio (SNR) and artifacts of diffusion weighted imaging (DWI) images, which ultimately will influence the quantitative of diffusion imaging. In this study, the effects of field strength on DWI are reviewed. The effects of the diseases also are discussed. Comparing DWI in cerebellum, WM, GM, Hyperacute region measurements both as a function of field strength (1.5T and 3.0T). Overall, the SNR of the DWI roughly doubled going from 1.5 T to 3.0 T. In summary, DWI studies at 3.0 T is provided significantly improved DWI measurements relative to studies at 1.5T.

Detection of DNA from Dermatophytes by Polymerase Chain Reaction (Polymerase chain reaction에 의한 동물 유래 피부사상균 DNA의 검출)

  • Kim, Young-Wook;Yeo, Sang-Geon;Choi, Woo-Pil
    • Korean Journal of Veterinary Research
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    • v.42 no.3
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    • pp.363-370
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    • 2002
  • For the development of diagnostic polymerase chain reaction (PCR) to fungal infection by dermatophytes Trichophyton and Microsporum, detection of the fungal DNA by PCR and analysis of the DNA pattern were undertaken in the present study. A total of 15 strains were tested and those consisted of 3 reference strains and 12 isolates such as: reference strains of T mentagrophytes (downy type, ATCC 9533), T rubrum (IFO 6204) and M gypseum (ATCC 9083), and each isolate of T mentogrophytes (powdery type), T mentagrophytes (granular type), T mentogrophytes (purple-red type), T rubrum, T raubitschekii, T tonsurans, T equinum, T ajelloi, T verrucosum, M cookei, M nanum and M gypseum. The DNA were purely isolated from all strains of Trichophyton spp. and Microsporum spp. by a simple method partly consisted of disruption of fungal cells by lyophilization and grinding and extraction of fungal DNA without phenol treatment which is a routine procedure in DNA isolation. For the detection of fungal DNAs, optimal condition of PCR was determined as preheating once at $94^{\circ}C$ for 5 min, 35 cycles of denaturation at $94^{\circ}C$ for 1 min, annealing at $38^{\circ}C$ for 1 min and polymerization at $72^{\circ}C$ for 2 min, and 1 cycle of final extension at $72^{\circ}C$ for 5 min. In PCR using arbitrary primers AP-1 (5' ACCCGACCTG3') and AP-2 (5' ACGGGCCAGT3'), DNAs in various numbers and sizes were detected from different species of Trichophyton and Microsporum, while DNAs in similar size were also detected in all strains of Trichophyton spp. and Microsporum spp. There were unique DNAs observed from certain dermatophytes by AP-1 such as 1,900 bases in T rubrum, 950 and 1,100 bases in T raubitscheldi, 2,100 bases in T equinum, 400 bases in T verrucosum and 1,150 bases in M gypseum. The unique DNAs were also observed by AP-2 such as 1,200 bases in T ajelloi, 250 bases in T verrucosum, 1,150 bases in M cookei and 2,000 bases in M nanum. The results indicated that PCR can detect a specific DNA from certain Trychophyton and Microsporum spp, which can be the information for further development of diagoomc PCR to dennatophytes.

A RF Resonator Using Square SRR at 3 T MRI (3 T 자기공명영상시스템에서의 SRR을 이용한 RF 공진기)

  • Son, Hyeok-Woo;Cho, Young-Ki;Yoo, Hyoungsuk
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.2
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    • pp.280-283
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    • 2015
  • This paper demonstrates a new radio frequency (RF) resonator at 3 T magnetic resonance imaging (MRI) system. An approach based on a split ring resonator (SRR) having effective metamaterial properties is investigated. Electromagnetic simulation results are compared for RF resonators and discussed in detail at 3 T. A new RF resonator has approximately 10% higher magnetic fields at the center of the human phantom than the previous RF resonator.

A Study on the Magnetic Properties of Melt-Spun (Fe, T)-Nd-C Alloys (TAl, Ti, Co, Ni)

  • Jang, T.S.;Cho, D.H.
    • Journal of Magnetics
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    • v.3 no.4
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    • pp.116-119
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    • 1998
  • Influence of small additions ($\leq$2.0 at.%) of Al, Ti, Co, and Ni on the microstructural development and the magnetic properties of melt-spun Fe-Bd-C alloys was investigated. Addition of these elements tended to stabilize the crystallization of as-spun ribbons. Especially, Al and Ti preferred to stabilize$ Fe_{17}Nd_2C_x.$ The average grain size of Fe17Nd2Cx (0.1~0.3 ${\mu}{\textrm}{m}$), obtained by a proper annealing, in the ribbon treated with 0.5 at.% additive was much smaller than that of additive-free ribbons, which would be the major source of large increase in coercivity. Among the additives, Ni was very effective to increase the coercivity whereas Co had beneficial effect on $T_c.$ By adding 0.5 at.% Ni, intrinsic coercivities of more than 1.4 T, 40~50% higher than that (~1.0T) of additive-free ribbons, can be obtained after annealing at 750~80$0^{\circ}C$.

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A Rare Case of Intestinal T-cell Lymphoma with Multiple Complications

  • Seung Yong Shin
    • Journal of Digestive Cancer Research
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    • v.11 no.2
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    • pp.114-118
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    • 2023
  • Intestinal T-cell lymphoma is a rare and aggressive form of non-Hodgkin lymphoma. Owing to its rarity and variable manifestations, intestinal T-cell lymphoma is usually diagnosed at an advanced stage. Therefore, it may be accompanied with serious complications at the time of diagnosis. Herein, I reports a case of intestinal T-cell lymphoma with multiple severe complications.

Nitrogen and Phosphorus Removal Efficiency of Aluminum Usage in DEPHANOX Process (DEPHANOX 공정 내 알루미늄 첨가에 따른 질소 및 인 제거 효율 평가)

  • Lee, Beom;Park, Noh-Back;Tian, Dong-Jie;Heo, Tae-Young;Jun, Hang-Bae
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.5
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    • pp.295-303
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    • 2012
  • Removal of total nitrogen (T-N) and total phosphorus (T-P) was evaluated in a DEPHANOX process by adding Al(III) to the separator to maintain T-P in the final effluent below 0.2 mg/L. pH in each reactor was maintained 7~8 after addition of Al(III) to the levels of 5, 10, 15 mg/L. The removal efficiency of COD and T-N decreased at higher Al(III) dose, but T-P removal efficiency increased from 76.28 to 84.02, 94.66% at Al(III) dose of 5, 10, 15 mg/L, respectively. T-P in effluent showed 0.17 mg/L at Al(III) dose of 15 mg/L. Minimum 15 mg/L of Al(III) was required to maitain T-P below 0.2 mg/L in the final effluent.