Optimization of transmission performance of 10-Gb/s optical vestigial sideband signals using electrical dispersion compensation by numerical simulation

We analyze the transmission performance of vestigial sideband (VSB) signals with electrical dispersion compensator (EDC) by numerical simulations. Optimizing the dispersion and bandwidth of EDC, and the extinction ratio and chirp of the modulator, we can improve the dispersion tolerance of VSB signals. VSB signals with negative chirp have better transmission performance while VSB signals with positive chirp are advantageous to the implementation of EDC due to low optimum dispersion in EDC. VSB transmission with EDC can be a very cost-effective solution for 10-Gb/s single-channel systems with the maximum transmission distance of 320 km.     

Identification of novel IgE-binding soybean allergens using serological analysis of a recombinant cDNA expression library (SEREX)

New immunoglobulin E (IgE)-binding proteins from soybean (Glycine max L.) were identified using serological analysis of a recombinant cDNA expression library (SEREX) derived from soybean seeds and an enzyme-linked immunosorbent assay (ELISA). A soybean cDNA expression library was synthesized using the lambda ZAP express phage vector system and screened using sera of soybean-sensitive patients with atopic dermatitis (AD). A total of 3 new IgE-binding soybean proteins were identified as enolase, triosephosphate isomerase (TPI), and malate dehydrogenase (MDH). Full-length cDNAs were cloned into the expression vector pET15b, and expressed in Escherichia coli BL21 (DE3). The recombinant proteins were purified using affinity chromatography, followed by ELISA, with the sera of AD patients, resulting in positive reactions. The cDNA sequences were submitted to the GenBank Nucleotide Sequence Database with the accession numbers AY496909 (enolase), AY631048 (TPI), and AY496910 (MDH).     

A 20 GHz Steerable Array Antenna Using 3-bit Dielectric Slab Phase Shifters on a Coplanar Waveguide

A simple steerable array antenna is designed and developed using a movable dielectric phase shifter. The change of effective dielectric constant at different dielectric slab positions on a coplanar waveguide is used as the phase shifter. The impedance matching and desired phase shift conditions are satisfied at two slab heights, and the reflection is designed to be minimized at these slab positions. The low-loss dielectric material is used as the dielectric slab and is placed close to a coplanar transmission line with airgap. The 4times4 steerable array antenna with the phase shifters is designed and fabricated at 20 GHz. The H-plane radiation patterns are measured at different phase shift positions and compared with the expected results     

Ruthenium(II)‐ or Rhodium(III)‐Catalyzed Grignard‐Type Addition of Indolines and Indoles to Activated Carbonyl Compounds

The ruthenium(II)‐ or rhodium(III)‐catalyzed pyrimidinyl‐directed Grignard‐type C−H additions of N‐heterocycles with activated aldehydes and ketones are described. A cationic ruthenium catalyst and sodium acetate additive in dichloroethane as solvent were found to be optimal catalytic system for the construction of C‐7 alkylated indolines. In sharp contrast, a cationic rhodium complex allows the generation of C‐2 alkylated indoles and pyrroles as well as C‐1 alkylated carbazoles. The site‐selective C−H functionalization of these heterocyclic scaffolds could be an important asset towards the development of novel bioactive compounds.

     

Elastic contact between rough surfaces: Effect of roughness at large and small wavelengths

The area and pressure distribution in elastic contacts between frictionless, nonadhesive surfaces is studied as a function of load and surface geometry using finite element calculations. Surfaces that follow self-affine scaling on all resolved scales are compared to surfaces with cutoffs at small and large length scales, and experimental surfaces that are not self-affine. In all cases the true area of contact is proportional to load and inversely proportional to elastic modulus and the mean slope of the surface. The constant of proportionality κ is nearly constant and lies between analytic predictions. Large wavelength cutoffs lead to a small increase in κ, a homogeneous distribution of contacts at large scales, and limit the size of the largest connected regions. Small wavelength cutoffs lead to local redistributions in pressure that decrease the probability of low and high local pressures.     

韩国国立公园管理公团

韩国的国立公园在1987年以前由地方政府管理,后将管理权移交给中央政府.地方政府的管理由于缺乏专业性,管理体系复杂和管理预算不足等原因,各地方在管理水平、管理方式上存在很大的差异.因此,由民间专家组成的国立公园管理公团机构应运而生.介绍了1987年前后,韩国国立公园的问题和解决方案的摸索过程以及中央政府的直接管理背景及优点.     

Scalable fabrication of carbon nanotube/polymer nanocomposite membranes for high flux gas transport

We present a simple, fast, and practical route to vertically align carbon nanotubes on a porous support using a combination of self-assembly and filtration methods. The advantage of this approach is that it can be easily scaled up to large surface areas, allowing the fabrication of membranes for practical gas separation applications. The gas transport properties of thus constructed nanotube/polymer nanocomposite membranes are analogous to those of carbon nanotube membranes grown by chemical vapor deposition. This paper shows the first data for transport of gas mixtures through carbon nanotube membranes. The permeation of gas mixtures through the membranes exhibits different properties than those observed using single-gas experiments, confirming that non-Knudsen transport occurs.     

Inter-laboratory correlation exercise on a light-duty diesel passenger vehicle to verify nano-particle emission characteristics by Korea particle measurement program

The Light Duty Inter-Laboratory Correlation Exercise (ILCE) final report, performed with the ‘PMP Golden Vehicle’ at nine laboratories in the EU, Korea and Japan to demonstrate repeatability and reproducibility of the particle number concentration emissions measurement techniques proposed by the Particle Measurement Program (PMP), was released in 2007. The ILCE was conducted by the Korea Particle Measurement Program (KPMP) with a domestic diesel passenger vehicle equipped with a diesel particulate filter (DPF) between three certification laboratories and the research center of an automotive manufacturer to meet future regulations (EURO 5 and EURO 6) of particle number concentration for light-duty vehicles in early 2008. This research focused on measuring the particulate matter emission (particle number and mass) levels of a representative light-duty diesel passenger vehicle during new European driving cycle (NEDC) mode to analyze the repeatability and reproducibility between laboratories in Korea. From the ILCE test results in Korea, the mean total particle number concentration levels ranged from 5.43E+10 #/km to 1.58E+11 #/km and 0.0003 g/km to 0.0036 g/km for particle mass. Repeatability between participating laboratories ranged from 32% to 66% for particle number, 11% to 70% for particle mass; the reproducibility level was 46% for particle number, and 66% for particle mass emission. This paper was recommended for publication in revised form by Associate Editor Kyoung Doug Min Simsoo Park received his B.S. and M.S. degrees from Seoul National University in 1997 and 1979, respectively, and a Ph.D. from the State University of New York at Stony Brook. He served as a Chief Research Engineer at Hyundai Motor Company, a Director for Publication of the KSME, a Technical Advisor of Hyundai-Kia Motor Company, and an Editing Director, Project Director, International Director, Accounting Director, and General Affair Director of KSAE. He is currently Vice President and of Editor-in-Chief of IJAT at KSAE and a professor in school of mechanical engineering at Korea University.     

韩国雪岳山国立公园

雪岳山国立公园是韩国有代表性的国立公园之一,被指定为生物圈保护区,现在自然资源的保存状况良好,但由于韩国国土面积小,人口众多,雪岳山承受的观光开发的压力很大.主要论述雪岳山目前的管理状况及解决问题的方法.