• Title/Summary/Keyword: Converted sample stage

Search Result 5, Processing Time 0.021 seconds

Specimen Preparation for Scanning Electron Microscope Using a Converted Sample Stage

  • Kim, Hyelan;Kim, Hyo-Sik;Yu, Seungmin;Bae, Tae-Sung
    • Applied Microscopy
    • /
    • v.45 no.4
    • /
    • pp.214-217
    • /
    • 2015
  • This study introduces metal coating as an effective sample preparation method to remove charge-up caused by the shadow effect during field emission scanning electron microscope (FE-SEM) analysis of dynamic structured samples. During a FE-SEM analysis, charge-up occurs when the primary electrons (input electrons) that scan the specimens are not equal to the output electrons (secondary electrons, backscattered electrons, auger electrons, etc.) generated from the specimens. To remove charge-up, a metal layer of Pt, Au or Pd is applied on the surface of the sample. However, in some cases, charge-up still occurs due to the shadow effect. This study developed a coating method that effectively removes charge-up. By creating a converted sample stage capable of simultaneous tilt and rotation, the shadow effect was successfully removed, and image data without charge-up were obtained.

An Optimized Strategy for Genome Assembly of Sanger/pyrosequencing Hybrid Data using Available Software

  • Jeong, Hae-Young;Kim, Ji-Hyun F.
    • Genomics & Informatics
    • /
    • v.6 no.2
    • /
    • pp.87-90
    • /
    • 2008
  • During the last four years, the pyrosequencing-based 454 platform has rapidly displaced the traditional Sanger sequencing method due to its high throughput and cost effectiveness. Meanwhile, the Sanger sequencing methodology still provides the longest reads, and paired-end sequencing that is based on that chemistry offers an opportunity to ensure accurate assembly results. In this report, we describe an optimized approach for hybrid de novo genome assembly using pyrosequencing data and varying amounts of Sanger-type reads. 454 platform-derived contigs can be used as single non-breakable virtual reads or converted to simpler contigs that consist of editable, overlapping pseudoreads. These modified contigs maintain their integrity at the first jumpstarting assembly stage and are edited by fragmenting and rejoining. Pre-existing assembly software then can be applied for mixed assembly with 454-derived data and Sanger reads. An effective method for identifying genomic differences between reference and sample sequences in whole-genome resequencing procedures also is suggested.

A Synthesis of Unit Hydrograph by a Correlation Analysis between the Basin Characteristics and the Runoff-Characteristics - Han and Geum River Basin - (유역특성과 유출특성간의 상관관계 해석에 의한 단위유량도의 합성 - 한강 및 금강유역 -)

  • 윤용남;선우중호
    • Water for future
    • /
    • v.8 no.1
    • /
    • pp.61-79
    • /
    • 1975
  • An attempt is made to develope a scheme for synthesizing unit hydrograph for any arbitrary small watershed in the Han or Geum River basin, which can be applied in determining various sizes of design flood for flood control prijects. Stage gauging stations, seven in the Han and five in the Geun River basin with rating curves, were selected as subbasins for the analysis. Unit hydrographs of 2-hour duration were derived for several heavy storm events using the storm and the corresponding flood runoff data for each subbasin. The Clark method programmed by the Hydrologic Engineering Center, U.S. Corps of Engineers, was utilized for derivation of instantaneous unit hydrographs which were, in turn, converted into 2-hour unit hydrograph. By averaging the 2-hour unit hydrographs from several storm events a representative 2-hour unit hydrograph was determined for each subbasin and hence a separate derivation of dimensionless unit hedrograph was also possible for the Han and Geum River basins. The physiographic characteristics such as stream length, distance to the centroid of each watershed were correlated with the characteristic parameters of the derived unit hydrograph for the subbasins within two large basins. correlation analyses between the characteristic parameters were also made. These correlation analyses resulted a series of four equations and a dimensionless unit hydrograph for the two large basins, which made it possible to draw a synthetic 2-hour unitgraph for any small watershed within the Han or Geum River basin. A detailed procedure for aplying the derived method for an arbitrary basin is summarized with one sample computation for each of the two basins. A comparison of the actually derived 2-hour unit hydrogrograph and the synthesized one showed a fair agreement. A recommendation is made for the further study.

  • PDF

Forecast of Repair and Maintenance Costs for Public Rental Housing (공공임대주택의 유지관리를 위한 수선유지비용 예측)

  • Lee, Hak-Ju;Kim, Sunghee;Kim, Do-Hyung;Cho, Hunhee
    • Journal of the Korea Institute of Building Construction
    • /
    • v.18 no.6
    • /
    • pp.621-631
    • /
    • 2018
  • The repair and maintenance cost of domestic public rental housing is an issue of considerable interest and growing financial concern. This paper suggests a quantity-based model as an alternative method for predicting costs, instead of the conventional model which is based on actual cost data. Furthermore, this paper provides a forecast of the repair costs incurred each year during the multi family house's maintenance phase (40 years). The recently changed the long-term repair plan and quality-improved interior materials were considered into the research. In order to estimate the cost of maintenance work, 5 sample apartments were selected and analyzed. The repair and maintenance cost from the case studies was converted to cost per household and per floor area for general use. On the other hand, the net present value method was applied to reflect the effect of time. We expect that the results will help to establish expenditure plans that are more effective for public rental housing in the maintenance stage.

Increased Alcohol Decomposition Efficacy of Hoveina dulcis Extract by Carbohydrate-Hydrolyzing Enzymes (당 분해 효소를 이용한 헛개나무 열매 추출물이 알코올 분해에 미치는 영향)

  • Lee, Kyung-Seok;Kim, Ae-Jung;Lee, Ki-Young
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.22 no.4
    • /
    • pp.473-479
    • /
    • 2012
  • In this study, increased alcohol decomposition efficacy (ADH) of Hoveina dulcis extract by Carbohydrate-Hydrolyzing Enzymes was investigated. Carbohydrate decomposition enzymes such as Maxinvert (Invertase), Optidex L-400 (Glucoamylase) and Rohament CL (Cellulase & Pectinase) were added to Hoveina dulcis extract at different concentrations (0.01, 0.05, 0.1, 0.5 and 1%) for 48 hrs, after which samples were taken every 6 hrs for determination of ADH activity. As the enzyme concentration became higher, ADH activity also increased. Especially, the addition of 1% Rohament CL increased enzyme activity to 76% at 30 hrs incubation, after which the increase in activity stopped. In the rat and human body experiment, enzymatic decomposition of Hovenia dulcis extract by addition of 1% Rohament CL was also effective in decreasing serum alcohol concentration and respiration. Especially, in the early stage after alcohol consumption, the efficacy of enzyme treatment of Hovenia dulcis extract was more effective. These results show that if the glycoside forms of active compounds such as flavonols in Hovenia dulcis extract are converted into aglycone forms, alcohol decomposition capability can be enhanced.