• Title/Summary/Keyword: chemical index

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Relation of the Physico-chemical Properties of Forest Soil to Site Indices of Larix leptolepis Stands (산림 토양의 이화학적 성질과 낙엽송 임분의 지위지수와의 관계)

  • Park, Nam-Chang;Lee, Kwang-Soo;Park, Mun Sueb;Shin, Hyeon Chul;Jun, Kwon Seok;Jung, Su-Young
    • Journal of Korean Society of Forest Science
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    • v.97 no.6
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    • pp.589-596
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    • 2008
  • This study was carried out in order to estimate site indices in un-stocked land by the physico-chemical properties of forest soil and to investigate the distribution of the physico-chemical properties by soil horizons. In Larix leptolepis Gordon stand, 80 sites were selected respectively to A and B horizon in soil. About the analysis method of data there was used stepwise regression analysis. Soil pH and T.N. of the physico-chemical properties turned out to be positively related to the site index. However, O.M. and Avail. $P_2O_5$ in soil were found out negatively related. In the degree of contribution of the variables to site index by each one of the stands, the highly effective variables were Base Sat., C.E.C., Sand, Exch. $Ca^{{+}{+}}$, and Exch. $Mg^{{+}{+}}$ in A horizon, Exch. $Ca^{{+}{+}}$, Base Sat., T.N., Avail. $P_2O_5$, and Clay in B horizon, and Exch. $Ca^{{+}{+}}$ and Base Sat. in both of A and B horizon. In conclusion, these results will provide not only the important criteria for establishment of management forest plan in un-stocked land but also the useful guidance for selecting the suitable sites and trees.

NDVI Based on UAVs Mapping to Calculate the Damaged Areas of Chemical Accidents (화학물질사고 피해영역 산출을 위한 드론맵핑 기반의 정규식생지수 활용방안 연구)

  • Lim, Eontaek;Jung, Yonghan;Kim, Seongsam
    • Korean Journal of Remote Sensing
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    • v.38 no.6_3
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    • pp.1837-1846
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    • 2022
  • The annual increase in chemical accidents is causing damage to life and the environment due to the spread and residual of substances. Environmental damage investigation is more difficult to determine the geographical scope and timing than human damage investigation. Considering the reality that there is a lack of professional investigation personnel, it is urgent to develop an efficient quantitative evaluation method. In order to improve this situation, this paper conducted a chemical accidents investigation using unmanned aerial vehicles(UAV) equipped with various sensors. The damaged area was calculated by Ortho-image and strength of agreement was calculated using the normalized difference vegetation index image. As a result, the Cohen's Kappa coefficient was 0.649 (threshold 0.7). However, there is a limitation in that analysis has been performed based on the pixel of the normalized difference vegetation index. Therefore, there is a need for a chemical accident investigation plan that overcomes the limitations.

Study on the Physicochemistrical Property of the Clean Active Water Depositting on the Ceramic Stone by the Mineral-Oriental medicine (광물성 한약재 세라믹스톤 심적수의 이화학적인 특성에 대한 연구)

  • Kim Gyeong-Cheol
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.6
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    • pp.1548-1551
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    • 2004
  • studied on the physicochemistrical property of the clean active water depositting on the ceramic stone by the mineral-Oriental medicine. The results are as follows. The cluster of the clean active water is observed 53-66.5㎐ for contral water. The clean active water is observed 7.2 ph and 1.3330 refractive index for contral water. In the chemical experimental test by ICP, the clean active water is observed 102℃ in boiling point and 4.8㎎/100g V.E for 0㎎g/100g of contral water. In the antibiotic experimentation, an anion, the dimintion index of bacilli, radiation degree and radiate energy of the clean active water increased for contral water. And in the deodorization experimentation, the clean active water is observed 95% deodorization index.

TESTS FOR VARYING-COEFFICIENT PARTS ON VARYING-COEFFICIENT SINGLE-INDEX MODEL

  • Huang, Zhensheng;Zhang, Riquan
    • Journal of the Korean Mathematical Society
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    • v.47 no.2
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    • pp.385-407
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    • 2010
  • To study the relationship between the levels of chemical pollutants and the number of daily total hospital admissions for respiratory diseases and to find the effect of temperature/relative humidity on the admission number, Wong et al. [17] introduced the varying-coefficient single-index model (VCSIM). As pointed out, it is a popular multivariate nonparametric fitting technique. However, the tests of the model have not been very well developed. In this paper, based on the estimators obtained by the local linear technique, the average method and the one-step back-fitting technique in the VCSIM, the generalized likelihood ratio (GLR) tests for varying-coefficient parts on the VCSIM are established. Under the null hypotheses the new proposed GLR tests follow the $\chi^2$-distribution asymptotically with scale constant and degree of freedom independent of the nuisance parameters, known as Wilks phenomenon. Simulations are conducted to evaluate the test procedure empirically. A real example is used to illustrate the performance of the testing approach.

The Investigation of Influence of Chlorinated Hydrocarbons on $NO_x$ Formation from Methane Flames (메탄 화염에서 염화 탄화수소 화합물이 질소산화물 생성에 미치는 영향 조사)

  • Jang, Kyoung;Jang, Bong-Choon;Lee, Ki-Yong
    • Journal of the Korean Society of Combustion
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    • v.13 no.1
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    • pp.10-16
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    • 2008
  • Numerical simulations of freely propagating premixed flames burning mixtures of methane and chlorinated hydrocarbons in fuel are performed at atmospheric pressure in order to understand the effect of chlorinated hydrocarbons on the formation of nitrogen oxide. A detailed chemical reaction mechanism is used, the adopted scheme involving 89 gas-phase species and 1017 elementary forward reaction steps. Chlorine atoms available from chlorinated hydrocarbons inhibit the formation of nitrogen oxides by lowering the concentration of radical species. The reduction of NO emission index calculated with thermal or prompt NO mechanism is not linear and is probably related to the saturation effect as $CH_3Cl$ addition is increased, In the formation or consumption of nitrogen oxide, the $NO_2$ and NOCl reactions play an important role in lean flames while the HNO reactions do in rich flames. The molar ratio of Cl to H in fuel has an effect on the magnitude of NO emission index.

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The Characteristics of Water Quality in Mokpo Harbour(II) - Centering on eutrophication summer - (목포항의 수질특성 - 하계의 부영양화를 중심으로 -)

  • 김광수
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.3 no.S1
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    • pp.77-90
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    • 1997
  • the observations in situ and the seawater analyses were conducted in July and August, 1996 for the purpose of evaluating the characteristics of seawater quality centered on eutrophication in Mokpo harbour. By applying the OECD standards of trophic classification to the parameters such as secchi depth, total inorganic nitrogen, phosphate phosphorus and chlorophyll-a, the trophic level of seawater in Mokpo harbour was evaluated to be in eutrophic state in summer. By the estimation of pollution index with relation to eutrophication, the seawater quality of Mokpo harbour was evaluated to be under the regular grades and this evaluation was found to be different from the results of evaluation obtained by the environmental index of single parameter, chemical oxygen demand. By the estimation of eutrophication index, the seawaters of Mokpo harbour were shown to have the high potentiality of red tide occurrence.

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Effect of Mn and S Contents on Edge Cracking of Low Carbon Steels in Mini-Mill Process (미니밀공정 중 저탄소강의 에지크랙에 미치는 Mn 및 S의 영향)

  • 곽재현;정진환;조경목
    • Transactions of Materials Processing
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    • v.9 no.1
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    • pp.66-71
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    • 2000
  • The present study tackles the metallurgical subjects involving the thin slab-direct hot rolling process, i.e. mini-mill process. In order to clarify the effect of chemical composition of steel and MnS precipitation behaviors on the development of edge cracking during hot rolling, the content of manganese and sulfur in low carbon steel was varied and the isothermal treatment prior to roughing was applied. Edge cracking during roughing in the hot-rolling process of mini-mill was effectively prevented by means of the isothermal treatment at 115$0^{\circ}C$ for 5 minutes in the 0.4% manganese steel containing sulfur lower than 0.013%. With the increase in manganese content in low carbon steel, coarser MnS developed. The edge cracking index which denotes the total length of edge crack per unit edge-length of rolled specimens was proposed in this paper. It was found that the edge cracking index linearly decreased with the increase in the ratio of MnS.

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Correlation between the Thickness and Variation of Dielectric Conatant on SiOC thin film (SiOC 박막에서 박막의 두께와 유전율의 변화)

  • Oh, Teresa
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.12
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    • pp.2505-2510
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    • 2009
  • The SiOC films were deposited with the variation of flow rate ratios by chemical vapor deposition. It was researched the reason of decreasing the dielectric constant in SiOC film and the relationship between the dielectric constant and the thickness. The thickness of the deposited films tends to in proportion to the refractive index and the sample with the lowest dielectric constant decreased the thickness. The refractive index was decreased after annealing because of the decreasing of the film's thickness by annealing process.

Case studies: Statistical analysis of contributions of vitamins and phytochemicals to antioxidant activities in plant-based multivitamins through generalized partially double-index model

  • Yoo, Jae Keun;Kwon, Oran
    • Communications for Statistical Applications and Methods
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    • v.23 no.3
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    • pp.251-258
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    • 2016
  • It is important to verify the identity of plant-based multivitamins prepared with a natural-concept and popular for daily consumption because they are easily purchased in markets with imperfect information. For this study, a generalized partially double-index model (GPDIM) was employed as a main statistical method to identify the contribution of vitamins and phytochemicals to antioxidant potentials using data on antioxidant capacities and chemical fingerprinting. A bootstrapping approach via sufficient dimension reduction is adopted to estimate the two unknown coefficient vectors in the GPDIM. Fifth order polynomial regressions are fitted to measure the contributions of vitamins and phytochemicals after estimating the coefficient vectors with the two double indices.

Growth of CdTe Solar Cells and Surface Texturing of Photonic devices

  • Kim, Ji-Hyeon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.08a
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    • pp.27-27
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    • 2010
  • 결정성과 전하 이동도가 우수한 CdTe 박막을 증착하기 위하여 근접승화법(CSS), chemical spraying법, 전착(electrodeposition)법, screen printing법, 화학기상증착(MOCVD)법 및 sputtering법등이 응용되고 있으며 이들 방법은 각기 다양한 장단점을 가지고 있다. CdTe 태양전지를 성장시키는 다양한 방법 중에서 본 발표는 CBD를 이용한 CdS와 CSS를 이용한 CdTe 박막 태양전지를 성장하는 방법을 포함한다. 다양한 조건에서 성장된 박막의 물성과 CdCl2와 열처리를 통한 성능개선에 대해 발표할 예정이다. 또한, 공기의 index와 박막의 index 차이가 크기 때문에, escape cone의 angle이 매우 작고, 박막의 경우 표면이 비교적 평평하기 때문에, 광소자(LED와 Solar Cell)는 표편 텍스처링이 성능을 향상시키기 위해 필요하다. Natural Lithography, Wet-etching, Dry-etching, index-grading을 이용하여, LED와 태양전지에서 uniform하고 대면적에 적용가능한 표면 택스처링 방법에 대해 발표할 예정이다.

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