• Title/Summary/Keyword: TEP

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Thermoelectric Power (TEP) Measurement To Assess Weld Integrity of HSLA Steel Welds (열기전력 측정을 이용한 고장력강 용접부의 미세조직의 고찰에 관한 연구)

  • Park, Yeong-Do
    • Proceedings of the KWS Conference
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    • 2005.06a
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    • pp.144-146
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    • 2005
  • Measurements of Thermoelectric power (TEP) were used to evaluate microstructural analysis in HSLA steel weldments. The measurements of TEP for weld microstructure across weldment have shown good correlation with hardness profile. The different TEP values indicated that changes in weld microstructure can be correlated with TEP values measured.

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The DSTM TEP for IPv4 and IPv6 Interoperability (IPv4/IPv6의 연동을 위한 DSTM TEP의 기능)

  • 진재경;최영지;민상원
    • Journal of KIISE:Computing Practices and Letters
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    • v.9 no.5
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    • pp.578-587
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    • 2003
  • The DSTM (Dual Stack Transition Mechanism), one of tunneling mechanism, is considered as the best solution in IPv4/IPv6 transition recently. The DSTM provides a method to assure IPv4/v6 connectivity based on 4over6 (IPv4-over-IPv6) tunneling and temporal allocation of a global IPv4 address to a host requiring such communication. A TEP (Tunnel End Point) operates as a border router between IPv6 domain and IPv4 Internet, which performs encapsulation and decapsulation of 4over6 tunneling packets to assure hi-directional forwarding between both networks. In this paper, we analyze basic standards of the IPv6 protocol. And, we design and implement a DSTM TEP daemon block. The TEP daemon analyzes a fevers tunneling packet that is forwarded by the DSTM node, establishes the TEP's 4over6 interface, and supplies communication between a DSTM and a IPv4-only node. Finally, we construct a DSTM testbed and measure performance of the DSTM TEP. Our observation results show that performance of TEP supports the DSTM service.

Spatial Distribution of Transparent Exopolymer Particles(TEP) and Their Relation to Carbon Species in the Euphotic Layer of the Northern East Sea (동해 북부해역 유광층에서 TEP 분포와 이산화탄소 인자와의 상호관련성)

  • Jeon, Hyun-Duck;Rho, Tae-Keun;Lee, Tong-Sup
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.17 no.2
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    • pp.33-44
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    • 2012
  • Transparent exopolymer particles (TEP) are formed by aggregation of polysaccharide products excreted by phytoplankton and have sticky character like gel. They play important role in the production of marine snow in water column. To study the distribution pattern of TEP concentration and its role in carbon cycle in the surface ocean, we measured pH, Total alkalinity (TA), and chlorophyll-a in addition to physical characteristics of seawater within the surface water column. TEP concentrations ranged from nearly undetectable values to $338{\mu}g\;Xeq\;l^{-1}$. They were considerably lower than previously reported values from costal sites, but showed similar values observed in other oceanic region during phytoplankton bloom periods. The spatial distribution of TEP concentrations were similar to those of chlorophyll-a, which indicate that the production of TEP were closely related to phytoplankton. Calculated total dissolved inorganic carbon ($TCO_2$) from the pH and TA was normalized to 35 psu of salinity ($NTCO_2$) and showed negative linear relationship with temperature. Biological drawdown of $NTCO_2$ ($NTCO_{2bio}$) was estimated from the difference between theoretical $NTCO_2$ values and observed $NTCO_2$. In the warm region located south of $40^{\circ}N$ along the $132.5^{\circ}N$ meridional lines, $NTCO_{2bio}$ showed negative value and TEP concentrations were high. This suggested that negative $NTCO_{2bio}$ may be attributed to the biological processes. At the stations located between 44 and $46^{\circ}N$, TEP concentrations showed high concentration at the chlorophyll-a maximum layer within the water column while they showed low concentration in the surface layer. Carbon content of TEP constituted about 40% of $NTCO_{2bio}$ at the chlorophylla maximum layer. In this study, we could not observe any positive and negative relationship between TEP concentration and $NTCO_2$ or pH. It is obvious that we should consider the importance of TEP in the biological carbon cycling processes within surface layer.

Thermoelectric power and resistivity of the Sr$_{1-x}K_xBiO_3$ superconductor

  • Kim, D.C.;Kim, J.S.;Joo, S.J.;Bougerol-Chaillout, C.;Kazakov, S.M.;Pshirkov, J.S.;Antipov, E.V.;Park, Y.W.
    • 한국초전도학회:학술대회논문집
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    • v.9
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    • pp.229-232
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    • 1999
  • We have measured the temperature dependence of thermoelectric power (TEP) and resistivity for the Sr$_{1-x}K_xBiO_3$ superconductor (x=0.45-0.6). At T=10.2K, the resisitivity starts to increase from zero and a rather broad superconducting phase transition (${\Delta}$T ${\sim}$ 2.3K) is observed. TEP at room temperature has a small negative value ( S =-1.96${\mu}$V/K), characteristic of metallic-like TEP. The temperature dependence of TEP shows two distinct features. With decreasing temperature from room temperature, the absolute value of TEP decreases and the sign of TEP changes from negative to positive around 200k. Also, the negative slope of TEP(dS/dT) decreases substantially and becomes rather flat at around 160k, which is a feature already noted in Ba$_{1-x}K_xBiO_3$[1].

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Development and Application TEP Activity for the Education of Experimental Apparatus at Elementary School (초등학생의 실험기구 교육을 위한 TEP 활동의 개발 및 적용)

  • Jeon, Soyeon;Park, Jongseok
    • Journal of the Korean Chemical Society
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    • v.64 no.6
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    • pp.379-388
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    • 2020
  • The purpose of this study are to develop the TEP activity for learning experimental apparatus at elementary school and to test the effects of the TEP activity. This study consists of two steps. First through literature research on the difficulties and needs of experimental apparatus education developed the form that how to educate the experimental apparatus at elementary school. Second, applied the TEP activity and figured out the effects as two aspect(knowledge about experimental apparatus and actual using skill during lesson). This worksheet was applied to 3rd grade students in elementary school about 4 experimental apparatuses(Beaker, Electronic scale, Glass rod, Spatula). The results of this study are as follows: There is no specific time to teach what is and how to use experimental apparatus by regular curriculum. So many students and teachers need method and time to learn them. Also they want to lots of opportunities to use them. With that needs given previously, TEP activity developed by 3 steps. 1. Trigger interest 2. Explore experimental apparatus: learned knowledges about experimental apparatus focused on appearance(name, purpose, directions for use, precautions) 3. Practice experimental apparatus: actual using time to acquire skills. After that did the survey of knowledge and observation of students' behavior during usual class to confirm the effects. According to the results, TEP activity helped the students to improve there awareness of the experimental apparatus and actual using skills.

Study on the Recovery and Recrystalligation of Cold-lolled Zr-based Alloys by Thermoelectric Power Measurement During Isothermal Annealing (TEP 분석을 이용한 냉간가공된 Zr-based 합금의 등온열처리에 따른 회복 및 재결정 거동에 관한 연구)

  • O, Yeong-Min;Jeong, Heung-Sik;Kim, Seon-Jin
    • Korean Journal of Materials Research
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    • v.11 no.6
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    • pp.483-491
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    • 2001
  • The recovery and recrystallization behavior of cold-rolled Zr-based alloys during isothermal annealing at temperatures from $575^{\circ}C$ to $650^{\circ}C$ was studied by thermoelectric power and Vickers microhardness measurement. The recovery and recrystallization resulted in the increase of TEP doe to the extinction of lattice defect, vacancy, dislocation and stacking fault during isothermal annealing after cold- rolling. The completion of recrystallization could be determined much clearly by TEP behavior than by microhardness change in Zr-based alloys. Especially, the recovery and recrystallization were classified separately by TEP behavior in Zr-0.4Nb-xSn alloys. From the analysis of TEP behavior and microhardness, the addition of Sn caused to form the interaction between stain field and dislocation, which resulted in the delay of recovery in Zr-based alloys. The precipitation due the addition of Nb suppressed the grain growth after recrystallization effectively in Zr-based alloys.

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Definitive Closure of the Tracheoesophageal Puncture Site after Oncologic Laryngectomy: A Systematic Review and Meta-Analysis

  • Escandon, Joseph M.;Mohammad, Arbab;Mathews, Saumya;Bustos, Valeria P.;Santamaria, Eric;Ciudad, Pedro;Chen, Hung-Chi;Langstein, Howard N.;Manrique, Oscar J.
    • Archives of Plastic Surgery
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    • v.49 no.5
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    • pp.617-632
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    • 2022
  • Tracheoesophageal puncture (TEP) and voice prosthesis insertion following laryngectomy may fail to form an adequate seal. When spontaneous closure of the fistula tract does not occur after conservative measures, surgical closure is required. The purpose of this study was to summarize the available evidence on surgical methods for TEP site closure. A comprehensive search across PubMed, Web of Science, SCOPUS, and Cochrane was performed to identify studies describing surgical techniques, outcomes, and complications for TEP closure. We evaluated the rate of unsuccessful TEP closure after surgical management. A meta-analysis with a random-effect method was performed. Thirty-four studies reporting on 144 patients satisfied inclusion criteria. The overall incidence of an unsuccessful TEP surgical closure was 6% (95% confidence interval [CI] 1-13%). Subgroup analysis showed an unsuccessful TEP closure rate for silicone button of 8% (95% CI < 1-43%), 7% (95% CI < 1-34%) for dermal graft interposition, < 1% (95% CI < 1-37%) for radial forearm free flap, < 1% (95% CI < 1-52%) for ligation of the fistula, 17% (95% CI < 1-64%) for interposition of a deltopectoral flap, 9% (95% CI < 1-28%) for primary closure, and 2% (95% CI < 1-20%) for interposition of a sternocleidomastoid muscle flap. Critical assessment of the reconstructive modality should take into consideration previous history of surgery or radiotherapy. Nonirradiated fields and small defects may benefit from fistula excision and tracheal and esophageal multilayer closure. In cases of previous radiotherapy, local flaps or free tissue transfer yield high successful TEP closure rates. Depending on the defect size, sternocleidomastoid muscle flap or fasciocutaneous free flaps are optimal alternatives.

Welfare Consequences of Tradeable Emission Permits in a Product Differentiated Market (상품차별화된 시장에서 배출권거래제도의 후생효과)

  • Park, Sang Ha;Lee, Sang Ho
    • Environmental and Resource Economics Review
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    • v.11 no.3
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    • pp.415-446
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    • 2002
  • Due to its cost effectiveness, tradeable emission permits (TEP) system has been effectively used in the USA and many other advanced countries. But, academic many researchers have been argued that TEP system would not work as an efficient regulatory tools when there are imperfect competition in permits and/or products markets. Sartzetakis (1997), however, show that TEP system can serve as an effective environmental regulation under the certain demand/cost conditions even though duopolistic production market is not competitive. In this paper we extend Sartzetakis's analysis into the differentiated products markets under the same cost conditions, and examine the relative efficiency of TEP system by comparing it with the command and control system. We then show that the main results of Sartzetakis can hold if two differentiated products markets have the symmetric demands. In particular, it is revealed that social welfare will be increased under TEP system even though consumer surplus may be decreased.

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Recrystallization TEP Behavior of Zr-based alloy by addition of Nb and Sn (Nb과 Sn 첨가에 따른 Zr 합금의 재결정 및 TEP 거동)

  • Jeong, Heung-Sik;O, Yeong-Min;Jeong, Yong-Hwan;Kim, Seon-Jin
    • Korean Journal of Materials Research
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    • v.11 no.2
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    • pp.104-114
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    • 2001
  • To investigate the effects of the addition of Nb and Sn on the recrystallization of Zr- Sn-Nb alloys, both Vickers micro-hardness test and TEP measurement were carried out on cold-worked specimens annealed at various temperatures from $300^{\circ}C$ to 75$0^{\circ}C$. The microstructures of heat treated specimens were analyzed by optical microscope, SEM, and TEM. The study of microhardness and microstructures showed that both recrystallization process and grain growth were retarded as the activation energy was increased by the addition of Nb and Sn. Especially, the addition of Sn was more effective on retarding recrystallization. Precipitates were formed more easily when Nb was added because the solubility of Nb into Zr is lower than that of Sn. However, the recrystallization process was affected more by Sn than Nb because the strain field formed by substitutional Sn repressed the dislocation movement. TEP was increased due to the decrease of electron scattering as recovery and recrystallization were proceeded and saturated when the recrystallization completed. However, when precipitates formed, TEP was increased because the decrease of solute concentration near the precipitates caused the decrease of electron scattering.

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A Study on the Solubility of Nb in Zr-0.8Sn Alloy by Thermoelectric Power Measurement (TEP 측정방법을 이용한 Zr-0.8Sn 합금의 Nb 고용도에 관한 연구)

  • Oh, Yeong-Min;Jeong, Heung-Sik;Jeong, Yong-Hwan;Kim, Seon-Jin
    • Korean Journal of Materials Research
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    • v.11 no.6
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    • pp.453-459
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    • 2001
  • It is important for the fabrication of nuclear cladding to optimize the microstructure, because the properties of Zr-based nuclear claddings such as mechanical properties, oxidation-resistance and corrosion- resistance vary widely with its microstructure. The microstructure in Zr-based alloy is strongly dependent on the solubility of alloying element. However, it is very difficult to measure the solubility due to the low solution limit of alloying elements in Zr-based alloy. In this study, Thermoelectric Power(TEP) measurements are used to determine the solubility of Nb in Zr-0.8Sn alloy, which is confirmed by optical microscopy and transmission electron microscopy. The solutioning of Nb obtained by a homogenization treatment and water-quench leads to a decrease of TEP The saturation of TEP appears with the increase of homogenization temperature, which means the saturation of the Nb content in the matrix. From these results, the solubility ($C_{Nb}$) of Nb in Zr-0.8Sn with temperature could be expressed as fellow equation : $4.69097{\times}10^{16}{\times}e^{-25300\times\;I/T}$(ppm.at.%)

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