• Title/Summary/Keyword: Structure determination

Search Result 1,004, Processing Time 0.03 seconds

The Joint Determination of Leverage and Debt Maturity (레버리지와 부채만기 결정의 상호관계)

  • Kim, Chi-Soo;Kwon, Kyeung-Taek
    • The Korean Journal of Financial Management
    • /
    • v.22 no.1
    • /
    • pp.1-36
    • /
    • 2005
  • In this study, we analyzed determinant factors of leverage ratio and debt maturity for Korean firms in the simultaneous equation system using 2SLS (two stage least square) method under assumption that two variables are jointly determined in the capital structure decision. As a result of the analysis, we found that leverage ratio and debt maturity are positively related. Also, as for determinant factors of debt maturity, agency cost hypothesis, asset maturity matching hypothesis, signalling and liquidity risk hypothesis are all generally supported, and further leverage ratio are significantly positively related with firm size, but negatively related with default risk. However, when we divided samples into groups according to bank debt level and Chaebul affiliation, with contrast to existing study which worked on similar issues with OLS, we found no evidence supporting the argument that the information asymmetry problem is less severe in firms with more bank debt, whereas information asymmetry and financial constraint problems are more severe in non-Chaebul affiliated firms.

  • PDF

Robust determination of control parameters in K chart with respect to data structures (데이터 구조에 강건한 K 관리도의 관리 모수 결정)

  • Park, Ingkeun;Lee, Sungim
    • Journal of the Korean Data and Information Science Society
    • /
    • v.26 no.6
    • /
    • pp.1353-1366
    • /
    • 2015
  • These days Shewhart control chart for evaluating stability of the process is widely used in various field. But it must follow strict assumption of distribution. In real-life problems, this assumption is often violated when many quality characteristics follow non-normal distribution. Moreover, it is more serious in multivariate quality characteristics. To overcome this problem, many researchers have studied the non-parametric control charts. Recently, SVDD (Support Vector Data Description) control chart based on RBF (Radial Basis Function) Kernel, which is called K-chart, determines description of data region on in-control process and is used in various field. But it is important to select kernel parameter or etc. in order to apply the K-chart and they must be predetermined. For this, many researchers use grid search for optimizing parameters. But it has some problems such as selecting search range, calculating cost and time, etc. In this paper, we research the efficiency of selecting parameter regions as data structure vary via simulation study and propose a new method for determining parameters so that it can be easily used and discuss a robust choice of parameters for various data structures. In addition, we apply it on the real example and evaluate its performance.

The wage determinants of the vocational high school graduates using mixed effects mode (혼합모형을 이용한 특성화고 졸업생의 임금결정요인 분석)

  • Ryu, Jangsoo;Cho, Jangsik
    • Journal of the Korean Data and Information Science Society
    • /
    • v.27 no.4
    • /
    • pp.935-946
    • /
    • 2016
  • In this paper, we analyzed wage determinants of the vocational high school graduates utilizing both individual-level and work region-level variables. We formulate the models in the way wage determination has multi-level structure in the sense that individual wage is influenced by individual-level variables (level-1) and work region-level (level-2) variables. To incorporate dependency between individual wages into the model, we utilize hierarchical linear model (HLM). The major results are as follows. First, it is shown that the HLM model is better than the OLS regression models which do not take level-1 and level-2 variables simultaneously into account. Second, random effects on sex, maester dummy and engineering dummy variables are statistically significant. Third, the fixed effects on business hours and mean wage of regular job for level-2 variables are statistically significant effect individual-level wages. Finally, parental education level, parental income, number of licenses and high school grade are statistically significant for higher individual-level wages.

Determination of Properties of Ionomer Binder Using a Porous Plug Model for Preparation of Electrodes of Membrane-Electrode Assemblies for Polymer Electrolyte Fuel Cells

  • Park, Jin-Soo;Park, Seok-Hee;Park, Gu-Gon;Lee, Won-Yong;Kim, Chang-Soo;Moon, Seung-Hyeon
    • Journal of the Korean Electrochemical Society
    • /
    • v.10 no.4
    • /
    • pp.295-300
    • /
    • 2007
  • A new characterization method using a porous plug model was proposed to determine the degree of sulfonation (DS) of ionomer binder with respect to the membrane used in membrane-electrode assemblies (MEAs) and to analyze the fraction of proton pathways through ionomer-catalyst combined electrodes in MEAs for polymer electrolyte fuel cells (PEFCs). Sulfonated poly(ether ether ketone) was prepared to use a polymeric electrolyte and laboratory-made SPEEK solution (5wt.%, DMAc based) was added to catalyst slurry to form catalyst layers. In case of the SPEEK-based MEAs in this study, DS of ionomer binder for catalyst layers should be the same or higher than that of the SPEEK membrane used in the MEAs. The porous plug model suggested that most of protons were via the ionomer binder (${\sim}92.5%$) bridging the catalyst surface to the polymeric electrolyte, compared with the pathways through the alternative between the interstitial water on the surface of ionomer binder or catalyst and the ionomer binder (${\sim}7.3%$) and through only the interstitial water on the surface of ionomer or catalyst (${\sim}0.2%$) in the electrode of the MEA comprising of the sulfonated poly(ether ether ketone) membrane and the 5wt.% SPEEK ionomer binder. As a result, it was believed that the majority of proton at both electrodeds moves through ionomer binder until reaching to electrolyte membrane. The porous plug model of the electrodes of MEAs reemphasized the importance of well-optimized structure of ionomer binder and catalyst for fuel cells.

Effective Range Evaluation of Wireless Monitoring System for Monopile (모노파일용 원거리 무선 모니터링 시스템의 유효거리 평가)

  • Park, Kiwon;Lee, Jong-Sub;Choi, Changho;Byun, Yong-Hoon
    • Journal of the Korean GEO-environmental Society
    • /
    • v.13 no.6
    • /
    • pp.91-100
    • /
    • 2012
  • Wireless monitoring system for the structural health evaluation has a limit to the reliability of measured response. The objective of this study is to evaluate an effective measurement range of the wireless monitoring system on the analyzed data. For the wireless monitoring system, Bluetooth and Wi-Fi are applied to datalogger-receiver and receiver-personal computer, respectively. For the model of the monopile structure response, a laboratory-scale monopile is manufactured with Mono Cast Nylon and a lateral loading is applied by hammer impacting. Strain gauges attached on the model monopile are connected with the datalogger. The distances of datalogger-receiver and receiver-personal computer are changed for the evaluation of the measurement range. Experimental results show that the receiving rates of the response remain almost constant within limited distance, while the receiving rates dramatically decrease out of effective range. In addition, the receiving rates affect on the measured natural frequencies of the model monopile. This study suggests that the effective range evaluation of the wireless monitoring system may be used for the determination of a monitoring distance to the monopile installed in the offshore wind farm.

A Study on the Sun-Moon-Stars(日月星辰) appeared in Huang Ti Nei Chin(『黃帝內經』) (『황제내경(黃帝內經)』에 나타난 일월성진(日月星辰)에 관(關)한 연구(硏究))

  • Park, Chan-Yeong;Kim, Gi-Uk;Park, Hyeon-Guk
    • The Journal of Dong Guk Oriental Medicine
    • /
    • v.5
    • /
    • pp.281-306
    • /
    • 1996
  • A study on the effect of the Sun-Moon-Stars(日月星辰) in Huang Ti Nei Ching("黃帝內經") on the formation of the Yunqi theory(運氣理論) have revealed following conclusions. 1. There was a record of Stars(星辰) written by Gabgol-Character(甲骨文字) in the Yin(殷) Dynasty. But the very first documentary records of Stars(星辰) is Shu Jing("書經"). Ancient astronomy had the tendency of astrology of combined with theory of the Five Elements(五行) and finally effects the theory of formation of Huang Ti Nei Ching("黃帝內經"). 2. Shu Jing("書經") said that Junrak(錢樂) made an Armillary sphere(運天儀) in the Sung(宋) Dynasty. And in the Jin(秦) and the Han(漢) Dynasty, they already observed the stars. The Sunkiokhyung(璿機玉衡) which is machinery of star-observing, became to be called an Armillary sphere (運天儀) by the pass of times. 3. As of the theory of the Cosmos-structure(宇宙-構造論) in Ohanunhangdaeron("五運行大論"), Guiyugu(鬼兒區) announced the Hypothesis of Covering Heaven(蓋天說) but Kibak(岐伯) supported the Hypothesis of chaosheven's(蓋天說) and in the theory of atmosphere(大氣論) in Ohanunhangdaeron("五運行大論") said that the earth was in Great Empty(太虛) and it was floating in the universe by the Great Chi(大氣). 4. The knowledge about the Five stars(五星) in Huang Ti Nei Ching("黃帝內經") is presented in the section of Gemgwejineonron("金?眞言論"), Gigoupyondaeron("氣交變大論"), Youkwonjeonggidaeron("六元正紀大論").ln the method of identifying the Five stars(五星) presented the criteria of the brightness, the altitude, the colours and the orbit etc. 5. The jupiter which has twelve year's revolution cycle was the basis of determination on the Twelve constellation(12辰), the Twelve field of heaven(12次), the Twelve Houses in the ecliptic(黃道 12宮), the Twelve Earth's Branches(12支) and the Twelve fields of Earth(12分野) and also it became the origin of the duodecimals(12進法). 6. The saturn having about twenty-eight year's revolution cycle became the criterion in identifying the Twenty Eight Constellations(28宿) which was used as the coordinates of the Celestial sphere (天球). 7. By the Percussional movement(歲差運動), the position of polaris and the Vernal-Antumal equinox(春秋分点) were shifted. Therefore the ancient the Heaven Gate-Earth Door(天門-地戶) changed from the position of Sil-Byuk(室壁), Yik-Jin(翼軫). And the precisional movements brought about the concept of the WunHoyYunSe(元會運世) that is a method of dividing a period. Also the precisional movement gave three dimension(三次元) foundation interpreted the Sixty JiaZi (六十甲子) which is revolving through sixty years uniformally. 8. The Hypothesis of the Nine Houses and Eight Winds(九宮八風論) which is one field of the astrology of ancient polaris-nine Houses divination plate(太一九宮占盤) brought about the concept of deficiency and excess and the concept of the Wind Vice(風邪). In the Calendar System(曆法) presented in Huang Ti Nei Ching("黃帝內經") the tropical year of the Sun-Moon-Stars(日月星辰) and the revolution and the rotation of the earth give explanations the changes of Yin-Yang(陰陽) by the use of the ten Celestial branches(十干) and the twelve Earth branches(十二支).

  • PDF

Assessment of the Minimum Population Size for ex situ Conservation of Genetic Diversity in Aster altaicus var. uchiyamae Populations Inferred from AFLP Markers (AFLP 마커를 이용한 단양쑥부쟁이 개체군의 유전다양성 보전을 위한 최소개체군의 크기산정)

  • Kim, Chang-Kyun;Kim, Ho-Joon;Choi, Hong-Keun
    • Korean Journal of Environment and Ecology
    • /
    • v.25 no.4
    • /
    • pp.470-478
    • /
    • 2011
  • Aster altaicus var. uchiyamae is on the list of endangered species in Korea. Using amplified fragment length polymorphism (AFLP) markers, we investigated the genetic diversity within and among four populations (Guram, Dori Island, Samhap, and Danyang) of A. altaicus var. uchiyamae. We also present the collecting strategies that most efficiently capture the genetic diversity of A. altaicus var. uchiyamae. Four AFLP primer combinations produced a total of 936 bands, of which 934 (99.8%) were polymorphic. A high level of genetic diversity (PPB = 45.3%, h = 0.104, I = 0.168, hs = 0.108) was recognized within the populations of A. altaicus var. uchiyamae. A low degree of genetic differentiation ($G_{ST}$ = 0.075, ${\theta}^B$ = 0.079) was detected among the populations. In addition, analysis of molecular variance (AMOVA) showed that genetic variation was greater within populations (91%) than among populations (9%). These results indicate that the high rate of gene flow has played an important role in forming the present populations of A. altaicus var. uchiyamae. According to maximization strategy, 17, 16, and 11 individuals captured all of the genetic variation in Dori Island, Samhap, and Guram population, respectively. The determination the minimum population size of A. altaicus var. uchiyamae in terms of the genetic information is critical and thereby gain reliable decision support for ex situ conservation of the endangered species, A. altaicus var. uchiyamae.

A Semiological Study of Kim Soo-Young′s ″A Variation of Love″ (사랑의 변주곡에 대한 기호학적 접근)

  • 한명희
    • Lingua Humanitatis
    • /
    • v.1 no.2
    • /
    • pp.47-63
    • /
    • 2001
  • "A Variation of Love" is a characteristic Kim Soo-Young poem, in that it embodies the poet′s innovative use of language and proceeds speedily, like many of his other poems. Above all, the poem reveals the core of Kim′s poetical spirit, his speculation about love. The poem is difficult to understand because it broadly uses run-on lines and even run-on stanzas, a technique that many readers are unfamiliar with. The semiological approach of this paper will bring new light on the poem by restructuring the relationship between signs, that is, by taking apart the sign system of the original text and reconstructing its sentence structure. If we rearrange the poem from its original six stanzas and fifty-one lines to four stanzas and twenty-three lines, we will discover a close connection between stanzas 1 and 2, and between stanzas 3 and 4. Of the many keywords of the poem, we may establish the dominant word as "love," into which every poetic word converges and from which each word emanates. Another important keyword is "fatigue of the city" in stanza 4. Similarly negative aspects of the city may be found in the line "the same may be said of Bombay, of New York, of Seoul" in stanza 3, as well as in the words "desire" in combination with "the lamplights of Seoul like leftovers in the pig sty" in stanza 1. The persona of the poem tries to overcome the "fatigue of the city" by "love," but the way he realizes love is, somewhat peculiarly, through stillness and silence. The persona aligns "the stones of the peach and the apricot and the dried persimmon" with the his faith in love. He calls the stones "beautiful hardness" presumably because that hardness (the stillness and silence) may blossom into beauty. In the earlier stanzas, the persona′s quest for love results in an awareness that love is omnipresent, but the persona determines "not to shout it out loud." The reason for this determination is found in stanza 4. Those who experience the "fatigue of the city" will be able to realize it by themselves. This seemingly defeatist conclusion by no means suggest pessimism, for the persona holds the conviction that "there will come a day when [one] will rave for love." This conviction rescues the poem from the dismal mood suggested by the "fatigue of the city." At all events, it is important to note that the "fatigue of the city" should not be considered apart from "love." Yet, strangely enough, the poem embodies a severe critique of the city, and further investigation is necessary in order to clarify why this critique appears in the form of "love." But this will be the treated in another paper.

  • PDF

Polyacetylene Compounds from Panax ginseng C.A. Meyer (인삼의 Polyacetylene 화합물)

  • Shim Sang Chul;Chang Suk-Ku
    • Proceedings of the Ginseng society Conference
    • /
    • 1988.08a
    • /
    • pp.122-128
    • /
    • 1988
  • Several major polyacetylene compounds were isolated from the petroleum-ether fraction of fresh Korean ginseng roots through solvent fractionation. partition and silica gel column chromatography. Further separation of acetylenic compounds was accomplished by bonded normal phase HPLC utilizing a moderately nonpolar microparticulate column. The preparative separation for the various spectral measurements was carried out by low pressure preparative liquid chromatography. The chemical structure of these polyacetylenes separated was determined by UV. IR/FTIR. $^{1}H$ NMR. mass spectral and elemental analysis. These are identified to be heptadeca-1-en-4.6-diyn-3.9.l0.-triol [1] heptadeca-1.9-dien-4.6-diyn-3-ol. heptadeca-1.8-dien-4.6-diyn-3.10-diol and the 4th was denatured polyacetylene. heptadeca-1.4-dien-6.8-diyn-3.10-diol. Two different p-substituted benzoates of panaxynol were synthesized for the determination of exciton chirality. The circular dichroism spectra in the UV region show that panaxynol p-bromobenzoate and p-dimethyl-aminobenzoate constitute negative exciton chirality [2]. Isolated major polyacetylene compounds were irradiated in aerated solution with 300 nm UV light to obtain the oxidized product at the allylic alcohol center to corresponding carbonyl compounds such as heptadeca-1-en-4.6-diyn-9.10-diol-3-one and heptadeca-1.9-dien-4.6-diyn-3-one. These photooxidation compounds have en-on-diyne chromophore and undergo nucleophilic addition reaction with methanol to yield ${\beta}-methoxy$ carbonyl compounds such as heptadeca-9-en-4.6-diyn-1-methoxy-3-one and heptadeca-4.6-diyn-1-methoxy-9.10-diol-3-one.

  • PDF

Determination of Mn Oxidation State in Mn-(hydr)oxides using X-ray Photoelectron Spectroscopy(XPS) (X-선 광전자 분광법을 이용한 망간산화물의 망간 산화상태 해석)

  • Song, Kyung-Sun;Bae, Jong-Seong;Lee, Gie-Hyeon
    • Economic and Environmental Geology
    • /
    • v.42 no.5
    • /
    • pp.479-486
    • /
    • 2009
  • In natural environments, manganese (Mn) exists in the valence of +2, +3, and +4 and plays a pivotal role as a strong oxidant or reductant in the geochemical cycles of elements. Especially, Mn forms varying (oxyhydr)oxides. The oxidation state of structural Mn is characteristic to each oxide and is one of the most important factors controlling its geochemical behaviors such as solubility, sorption capacity, and redox potential. Therefore, it is important to elucidate processes governing Mn oxidation state in predicting the fate and transport of many redox sensitive elements in the environment. X-ray photoelectron spectroscopy (XPS) is a very useful method to determine the oxidation state of various elements in solid phases. In this study, the oxidation states of structural Mn in MnO, $Mn_2O_3$, $MnO_2$ were assessed based on the binding energy spectra of $Mn2p_{3/2}$ and Mn3s using XPS and were compared with those reported elsewhere. $Mn2p_{3/2}$ binding energies were determined as 640.9, 641.5, 641.8 eV for MnO, $Mn_2O_3$, $MnO_2$, respectively, which indicates that the binding energy increased with increasing Mn oxidation state. It was also noted that Ar etching may cause changes in electronic structure configuration on surface of the original sample.