• Title/Summary/Keyword: degree distribution

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Analysis of a Microstrip Substrate-Mounted Dielectric Resonator using FDTD Method and Pad Approximation (FDTD 법과 Pad 근사법을 이용한 마이크로 스트립 기판 위의 유전체 공진기 해석)

  • O, Sun-Su;Yun, Jung-Han;Lee, Seong-Mo;Park, Hyo-Dal
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.37 no.6
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    • pp.36-43
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    • 2000
  • Three-Dimensional FDTD method is applied to analyze the dielectric resonator coupled with two microstrip lines. We model accurately the curved surface using Noriaki model. The frequency resolution is 106.46 MHz by the conventional FFT However it is not sufficient for determining its resonant frequency. So we introduce the Pad approximation and Stoer-Bulirsch method in order to have the high frequency resolution degree, 1.00 MHz. All results are compared with the measured data. As a result, we acquire the very precise result through the Pad approximation. And sinusoidal wave is applied. From the plot of the electric and magnetic field distribution, it is shown that the resonant mode is TE$_{01{\delta}}$ mode.

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Studies on Accumulative Distribution of Cyanides and Metals in Stork청s Organ (황새의 각 장기조직중 청산염과 금속류의 분포 및 정량에 관한 연구)

  • 이완구;박상균;박성우
    • Journal of Environmental Health Sciences
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    • v.9 no.2
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    • pp.67-74
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    • 1983
  • An experimental study was carried out to determine the degree of contamination of cyanide and metals in each stork's (Ciconia c. boyciana) organ. The samples used for this experiment were gullet, respiratory tract, stomach content, rectum, lung, liver, heart, pancreas, gall, kidney, and muscles. Those samples were isolated by Conway microdiffusion method and determined by UV spectrophotometry for the cyanide, on the other hand, the samples for metals were dissolved by mercury digestion apparatus and analyzed by atomic absorption spectrophotometry. The results are as follows: 1) The quantities of cyanide accumulated in each organ were from 0.05 to 2.57 ppm and concentration of those in tissues was in order of 2.57 ppm in stomach content, 2.13 ppm in lung, 1.58 ppm in kidney, 1.22 ppm in gall, 0.52 ppm in pancreas, 0.32 ppm in heart, 0.25 ppm in rectum, 0.20 ppm in gullet, 0.19 ppm in liver, 0.07 ppm in muscles and 0.05 ppm in respiratory tract. 2) The calcium content is in a range of 10.89-105.74 ppm, iron is 2.47-557.70 ppm, zinc is 2.37-23.62 ppm, cupper is < 0.1- 1.76 ppm and cadmium, nickel, cobalt and lead is beyond 0.5 ppm, respectively.

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hp-Version of the Finite Element Analysis for Reissner-Mindlin Plates (Reissner-Mindlin 평판의 hp-Version 유한요소해석)

  • Woo, Kwang Sung;Lee, Gee Doug;Ko, Man Gi
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.13 no.2
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    • pp.151-160
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    • 1993
  • This paper is concerned with formulations of the hierarchical $C^{\circ}$-plate element on the basis of Reissner-Mindlin plate theory. On reason for the development of the aforementioned element based on Integrals of Legendre shape functions is that it is still difficult to construct elements based on h-version concepts which are accurate and stable against the shear locking effects. An adaptive mesh refinement and selective p-distribution of the polynomial degree using hp-version of the finite element method are proposed to verify the superior convergence and algorithmic efficiency with the help of the simply supported L-shaped plate problems.

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Experimental Investigation on Flow Characteristics of Chicken Blood in a Micro Tube Using a Micro-PIV Technique (마이크로 PIV를 이용한 미세튜브 내부 조류 혈액유동에 관한 실험적 연구)

  • Yeo, Chang-Sub;Ji, Ho-Seong;Lee, Sang-Joon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.11 s.254
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    • pp.1027-1034
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    • 2006
  • In order to investigate flow characteristics of chicken blood in a micro tube of 100$\mu$m in diameter, in-vitro experiments were carried out using a micro-PIV technique. The micro-PIV system consists of a microscope, 2-head Nd:YAG laser, 12 bit cooled CCD camera and a delay generator. Chicken blood with 40% hematocrit was supplied into a micro tube using a syringe pump. The blood flow shows clearly the cell free layer near the tube wall and its thickness is increased with increasing the flow speed. The hemorheological characteristics of chicken blood, including shear rate and shear stress were estimated from the PIV velocity field data obtained. Since the aggregation index of chicken blood is less than 50% of human blood, non-Newtonian flow characteristics of chicken blood are smaller than those of human blood. As the flow rate increases, the degree of flatness in the velocity profile at the center region is decreased and the parabola-shaped shear stress distribution becomes to have a linear profile. Under the same flow rate, chicken blood shows higher shear stress, compared with human blood.

Nano-Soot Particle Formation in Ethene/Air Inverse Diffusion Flame (에틸렌/공기 역 확산화염에서의 나노 매연 입자 생성)

  • Lee, Eui-Ju;Shin, Hyun-Joon;Oh, Kwang-Chul;Shin, Hyun-Dong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.9
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    • pp.1101-1109
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    • 2004
  • Experimental measurements of flame structure and soot characteristics were performed fur ethene inverse diffusion flames (IDF). IDF has been considered as the excellent flow field to study the incipient soot because soot particle do not experience the oxidation process. In this study, LIF image clarified the reaction zone of IDF with OH signal and PAH distribution. laser light scattering technique also identified the being of soot particle. To address the degree of soot maturing, C/H ratio and morphology of soot sample were investigated. From these measurements, the effect of flow residence time and temperature on soot inception could be suggested, and more details on soot characteristic in the IDF was determined according to fuel dilution and flame condition. The fuel dilution results in a decrease of temperature and enhancement of residence time, but the critical dilution mole fraction is existed for temperature not to effect on soot growth. Also, the soot inception evolved on the specific temperature and its morphology are independent of the fuel dilution ratio of fuel.

Finite Element Analysis of Solidification Process Using the Temperature-Enthalpy Relationship (온도-엔탈피 관계를 이용한 응고과정의 유한요소 해석)

  • Cho, Seong Soo;Ha, Sung Kyu
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.23 no.10
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    • pp.1213-1222
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    • 1999
  • A finite element method is developed for calculating the temperature and enthalpy distribution and accordingly the solid, liquid and mushy zone in a three-dimensional body subjected to any heat boundary conditions. The method concurrently consider both temperature and enthalpy for consideration of the latent heat effect, differently from other methods of using a special energy balance equation for solving a mushy zone. The developed brick element has eight nodes with one degree of freedom at each node. The numerical method and procedure are verified using the results of one and two dimensional analytic solutions and by other researchers. It is shown that the present method presents a consistent and stable results in either abrupt or ranged phase change problems. Moreover, the numerical results by the present method are hardly effected by the calculation time steps which otherwise are difficult to determine in most phase change problems. Finally, as a three-dimensional application, a T-shaped body of a phase change is presented and the temperature and enthalpy variation along the time are solved.

A study on the Solute Redistribution of Cu-Sn(P) Alloy (Cu-Sn(P) 합금(合金)의 용질재분배(溶質再分配)에 관(關)한 연구(硏究))

  • Shur, Su-Jeong;Cho, Soon-Hyunh;Kim, Ik-Soo;Yoon, Eui-Pak;Choi, Jeong-Cheol
    • Journal of Korea Foundry Society
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    • v.10 no.3
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    • pp.219-224
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    • 1990
  • In this, we have investigated the solute behavior in front of solid-liquid interface according to the change of the cooling rate in bronze alloy and phosphor bronze alloy. The conclusive summary is as follows: 1) The secondary dendrite arm spacing was decreased with increasing the cooling rate. 2) The minimum solute concentration happened to along centerline of primary arm, and the maximum solute concentration was found at the boundary of arm or between the arms the minimum solute concentration was increased with the cooling rate. 3) Segregation Index S was decreased with increasing the cooling rate and content of P. 4) The degree of the microsegregation was decreased with increasing the cooling rate. The effective distribution coefficient, Ke was increased with addition of P in Cu-Sn.

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The Toxicokinetic Characteristics of Korean Traditional Medicines (한약의 독물동태학적 특성)

  • Park, Yeong-Chul;Shin, Heon-Tae;Lee, Sun-Dong
    • Journal of Society of Preventive Korean Medicine
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    • v.15 no.2
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    • pp.1-19
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    • 2011
  • Toxicokinetics of Korean Traditional Medicines(TKM) is the description of what rate TKM will enter the body and what happens to it once it is in the body in terms of toxicology. However, it is not easy to understand TKM toxicokinetics because of various factors such as a mixture of 2-30 kinds of herbal materials containing thousands of chemicals, and complex chemical properties. For these reasons, little is known about toxicokinetics of TKM. This study was aimed to characterize and review the absorption, distribution and metabolism of korean traditional medicines in a view of toxicokinetics. For this aim, some of korean traditional medicines were reviewed on a basis of drug-drug interaction, biotransformation and intestinal metabolisms by bacteria. As the factors affecting mainly on toxicokinetics of TKM, individual herbal material's degree of lipophilicity and metabolic rate, and decoction components according to different kinds of herbal materials were considered. Other factors such as intestinal pH and bacterial activity for metabolism affecting on TKM toxicokinetics, especially in small intestine. It would be a better way for improving the adverse or poor effects caused by TCM if the factors affecting on toxicokinetics of TKM is considered.

Soot and NOx Emissions in Laminar Diffusion Flames: Effects of Air-Side versus Fuel-Side Diluent Addition (층류 확산화염에서의 매연과 질소산화물의 배출특성 : 공기측/연료측 희석제 첨가에 따른 영향)

  • Lee, Jong-Ho;Eom, Jae-Ho;Park, Chul-Woong;Jun, Chung-Hwan;Jang, Young-June
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.5
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    • pp.596-603
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    • 2003
  • Present study has been conducted to see the relative effects of adding N: to fuel-side and air-side on flame structure, soot formation and NOx emissions. Experiments were carried out to ascertain to what degree chemical kinetics and/or molecular transport effects can explain the differences in soot formation and NOx emission by studying laminar diffusion flames. Direct photograph was taken to see the flame structure. CARS techniques was used to get the flame temperature profiles. And spatial distribution of soot could be obtained by PLII method. CHEMKIN code was also used to estimate the global residence time to predict NOx emissions at each condition. Results from these studies indicate that fuel-side dilution is more effective than air-side dilution in view of NOx emissions. However, air-side dilution shows greater effectiveness over fuel-side dilution in soot formation. And turbulent mixing and heat transfer problems were thought to be considered in practical applications.

Coverage, Density and Completeness of Sources used in Tehran Metropolitan Area Cancer Registry: According to the Data of Esophageal Cancer, 2003-2007

  • Aghaei, Abbas;Najafi, Farid;Mosavi-Jarrahi, Alireza;Ahmadi-Jouibari, Toraj
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.8
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    • pp.3617-3619
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    • 2012
  • Background: The completeness of cancer registration is a major validity index of any reported cancer incidence. The present study aimed to evaluate the esophageal cancer incidence registered in the Tehran Metropolitan Area Cancer Registry. Materials and methods: The data on esophageal cancer abstracted from three sources of 1) pathology departments, 2) medical records, and 3) death certificates during 2003 till 2007 were utilized. The completeness of the data sources were evaluated using coverage (defined as the proportion of a community population with esophageal cancer identified by the source) and density (defined as the proportion of non-empty fields of the data by source). Results: A total 1,404 cases of esophageal cancer were reported for the duration of the study. Pathology provided 771, medical records 432, and death certificates 609. The coverage was 0.55 for pathology, 0.31 for medical records, and 0.43 for death certificates. The respective density values were 0.82, 0.96 and 0.98, respectively. Pathology (0.45) was the most complete source followed by medical records (0.42), and death certificates (0.29). Discussion: A low degree of completeness dictates putting more effort into case finding plus abstracting data more thoroughly.