• Speech Sciences
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• v.13 no.3
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• pp.49-65
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• 2006

Recently, several theories on the digital speech signal processing expanded the communication boundary between human beings and machines drastically. The aim of this study is to collect dialectal speech in Korea on a large scale and to establish a digital speech data base in order to provide the data base for further research on the Korean dialectal and the creation of value-added network. 528 informants across the country participated in this study. Acoustic characteristics of vowels and consonants are analyzed by Power spectrum and Spectrogram of CSL. Test words were made on the picture cards and letter cards which contained each vowel and each consonant in the initial position of words. Plot formants were depicted on a vowel chart and transitions of diphthongs were compared according to dialectal speech. Spectral times, VOT, VD, and TD were measured on a Spectrogram for stop consonants, and fricative frequency, intensity, and lateral formants (LF1, LF2, LF3) for fricative consonants. Nasal formants (NF1, NF2, NF3) were analyzed for different nasalities of nasal consonants. The acoustic characteristics of dialectal speech showed that young generation speakers did not show distinction between close-mid /e/ and open-mid$/\epsilon/$. The diphthongs /we/ and /wj/ showed simple vowels or diphthongs depending to dialect speech. The sibilant sound /s/ showed the aspiration preceded to fricative noise. Lateral /l/ realized variant /r/ in Kyungsang dialectal speech. The duration of nasal consonants in Chungchong dialectal speech were the longest among the dialects.

• Journal of the Korean Institute of Landscape Architecture
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• v.23 no.3
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• pp.48-58
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• 1995

This study was conducted to investigate the plant community and to propose ecological planning methods for urban environmental forest on Gaepo neighborhood park, Gangnamgu in Seoul. Thirty-six plots that the size of each plot was 10$\times$10m(100\ulcorner) were set up and the vegetation analysis was carried out. Field survey was executed Apirl, 1994. The actual vegetation was consisted of Poplulus$\times$albaglandulosa community(73.03%), Robinia pseudoacacia community(8.30%) P. $\times$ albaglandulosa-R.pseudoacacia community(1.81%) and environmental forest (15.22%) in the survey site. According to mean importance values of each plot, survey area were divided into ten forest communities. As for the analysis of plant community structure which was classified into ten forest communities, the importance values, ecological diversity, number of species, number of individuals, basal area and crown coverage of urban environmental forest were relatively lower than those of the native community. In urban environmental forest of Gaepo neighborhood park, it showed problems for the planting method. So urban environmental forest should be constructed considering ecological characteristics based on above results.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.253-254
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• 2006

초미세립 복합상 영구자석은 연 경자성상의 크기와 분포에 큰 영향을 받는 자성재료이다. 또한, 결정립간 교환상호작용력은 초미세립 복합상 영구자석의 잔류자속밀도에 큰 영향을 미친다. 이에 $Nd_8Fe_{86-x}Nb_xB_6$(x=0, 1, 2, 3) 조성으로 급냉자성 분말을 제조하고, 열처리 후 자기특성을 평가하였다. Nb 첨가에 따른 $Nd_2Fe_{14}B$ 상과 $\alpha$-Fe 상과의 교환상호작용력을 Henkel(${\delta}M$) plot을 통해 평가하고, 각 상의 크기와 분포를 조사하여 자기특성 변화를 합리화하였다. 본 연구에서 얻은 최대 자기특성은 $B_r$ = 9.791 kG, $_iH_c$ = 5.565 kOe, 그리고 $(BH)_{max}$ = 14.61 MGOe였고, Nb를 첨가함으로서 보자력이 증가하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.77-80
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• 2005

Local probe techniques such as scanning probe microscopy (SPM) or atomic force microscopy (AFM) extended our perception into ultra small world. Specially, the sense of touching was extended by AFM into the micro- and nanoworld and has provided complementary new insights of the microscopic world. In addition, touching objects is an essential step before trying to manipulate things. SPM as a touch sensor not only measure the mechanical properties but also detect different properties such as magnetic, electrical, ionic, thermal, chemical and biophysical properties in nanoscale and even less. Obtaining biophysical measurements, monitoring dynamics and processes together with high-resolution imaging of the biomolecules and cells with rather simpler sample preparation than any other techniques give great attractions to the scientists experimenting with biological samples. Among the many AFM capabilities we will specifically introduce the force plot which is used to measure tip-sample interactions and its application this time.

• Journal of Forest and Environmental Science
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• v.35 no.1
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• pp.1-5
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• 2019

Species diversity is one of the most important indices that used to evaluate the sustainability of forest communities. In the present study, three variables including number of individuals (frequency of species), basal area and volume of tree species were compared to estimate tree species diversity in broadleaves forests of Iran. Based on systematic random design, 30 plots (circle plot, $1000m^2$) was selected. Type of species, number of species, DBH and height of trees were measured. Simpson (1-D), Hill ($N_2$), Shannon-Wiener (H'), Mc Arthur ($N_1$), Smith-Wilson ($E_{var}$) and Margalef ($R_1$) indices used to estimate tree species diversity. Species diversity was calculated in each plot. ANOVA test showed that there was a significant difference between of three variables used for estimation of species diversity. Number of trees variable has more precision than basal area and volume variables to estimate of species diversity. But Duncan test revealed that there were significant difference between of basal area and volume variables with number of trees. Therefore, basal area and volume variables were selected as more suitable variables in order to estimate of biodiversity indices in northern forests of Iran.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1199-1203
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• 2010

Second-order rate constants ($k_N$) have been measured spectrophotometrically for Michael-type reactions of 1-(X-substituted phenyl)-2-propyn-1-ones (2a-f) with a series of alicyclic secondary amines in MeCN at $25.0{\pm}0.1^{\circ}C$. The $k_N$ value increases as the incoming amine becomes more basic and the substituent X changes form an electron-donating group (EDG) to an electron-withdrawing group (EWG). The Br${\o}$nsted-type plots are linear with ${\beta}_{nuc}$ = 0.48 - 0.51. The Hammett plots for the reactions of 2a-f exhibit poor correlations but the corresponding Yukawa-Tsuno plots result in much better linear correlations with ${\rho}$ = 1.57 and r = 0.46 for the reactions with piperidine while ${\rho}$ = 1.72 and r = 0.39 for those with morpholine. The amines employed in this study are less reactive in MeCN than in water for reactions with substrates possessing an EDG, although they are ca. 8 pKa units more basic in the aprotic solvent. This indicates that the transition state (TS) is significantly more destabilized than the ground state (GS) in the aprotic solvent. It has been concluded that the reactions proceed through a stepwise mechanism with a partially charged TS, since such TS would be destabilized in the aprotic solvent due to the electronic repulsion between the negative-dipole end of MeCN and the negative charge of the TS. The fact that primary deuterium kinetic effect is absent supports a stepwise mechanism in which proton transfer occurs after the rate-determining step.

• Journal of Sensor Science and Technology
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• v.26 no.1
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• pp.15-23
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• 2017

In this study, bioelectrical impedance analysis, which has been used to assess an alteration in intracellular fluid (ICF) of the body, was applied to detect intravenous infiltration. The experimental results are described as follows. Firstly, when infiltration occurred, the resistance gradually decreased with time and frequency i.e., the resistance decreased with increasing time, proportional to the amount of infiltrated intravenous (IV) solution. At each frequency, the resistance gradually decreased with time, indicating the IV solution (also blood) accumulated in the extracellular fluid (ECF) (including interstitial fluid). Secondly, the resistance ratio started to increase at infiltration, showing the highest value after 1.4 min of infiltration, and gradually decreased thereafter. Thirdly, the impedance ($Z_C$) of cell membrane decreased significantly (especially at 50 kHz) during infiltration and gradually decreased thereafter. Fourthly, Cole-Cole plot indicated that the positions of (R, $X_C$) shifted toward left owing to infiltration, reflecting the IV solution accumulated in the ECF. The resistance ($R_0$) at zero frequency decreased continuously over time, indicating that it is a vital impedance parameter capable of detecting early infiltration during IV infusion. Finally, the mechanism of the current flowing through the ECF, cell membrane, and ICF in the subcutaneous tissues was analyzed as a function of time before and after infiltration, using an equivalent circuit model of the human cell. In conclusion, it was confirmed that the infiltration could be detected early using these impedance parameters during the infusion of IV solution.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.1 s.108
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• pp.71-80
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• 2005

In order to search for ecologically indicative characteristics on the street tree plots in Daegu area, plant communities and their floras were investigated. A total of 105 plots were collected and numerically analyzed by PCoA(Principal Coordinates Analysis). These plots were classified into 4 types containing 139 species, 97 genera, 42 families(including 37 exotic species): urban-dry type, urban-wet type, rural-dry type, rural-wet type. Habitat connectivity to the surrounding vegetation cover, extent and frequency of human impacts, and soil moisture recognizably were the main factors to allow the plots differentiation. Indicative species composition to these four types was generated as Eleusine indica-Eragrostis multicaulis-Oxalis corniculata to the urban-wet, Digitaria ciliaris-Eleusine indica-Eragrostis multicaulis to the urban-dry, Setaria viri-dis-Artemisia-Lactuca indica var. laciniata to the rural-wet, and Setaria viridis-Digitaria ciliaris-Erigeron canadensis to the rural-dry, respectively. Mean species number per plot for rural type was 2.5 times higher than for urban types. Street tree species representative to the rural-wet type is Zelkova serrata, which is a key species of potential natural vegetation in the alluvial land of Daegu area. Street tree plots were characterized by Eleusine indica showing the highest r-NCD value and also C4-assimilation grass plants. Views on the efficacy of the rural-wet type and the reinforcement of vegetation connectivity and soil moisture in rehabilitating street tree plots, are discussed.

• Korean Journal of Agricultural Science
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• v.42 no.3
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• pp.151-158
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• 2015

This study was conducted to know the variation and relationship of rice grain quality and starch pasting properties by transplanting times. Two early maturing rice cultivars which accounted for the most area of early maturing rice cultivar in Chungnam province were used. The experiment was laid out in a split-plot design with 3 replications. The main plot consisted of three transplanting times viz. early (April 25), ordinary (May 25) and late (June 25) with sub-plots containing two cultivars. According to the transplanting times, most of rice grain quality and starch pasting properties showed significant difference and Joami showed higher grain quality than Unkwang in all transplanting times. Especially, rice grain quality was improved when transplanted late, showing high head rice and glossiness of cooked rice due to the lower mean temperature during grain filling stage. Glossiness of cooked rice was positively correlated with head rice ratio, amylose content and setback value, and negatively correlated with chalky rice ratio and protein content. The highest positive and negative correlation were observed between breakdown value and peak viscosity ($r=0.98^{**}$), and breakdown and setback ($r=-0.94^{**}$), respectively. These results provide some information for rice researchers and producers producing cultivars with an improved quality, suggesting that rice quality is highly influenced by temperature at grain filling stage, and transplanting times is crucial in improving rice quality. In addition, starch pasting properties are useful for determining rice quality because rice grain quality and starch pasting properties are dependent on each other.

• Journal of Korean Society of Forest Science
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• v.99 no.2
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• pp.172-178
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• 2010

The status of ectomycorrhizal (ECM) fungal colonization in Pinus thunbergii seedlings was investigated 2 years after planting in an eastern coastal area of Korea. We established three $10{\times}10$ m plots at a P. thunbergii plantation in Gangneung and sampled lateral roots from 10 seedlings in each plot. ECMs were classified into morphological groups and the number of root tips of each morphotype was counted. In total, 8 ECM morphotypes were observed and fungal species that form each morphotype were identified by sequencing of the internal transcribed spacer (ITS) region of the nuclear rDNA. Suillus granulatus was the most abundant species (44.1-65.7% of relative abundance) in all plots, followed by Tomentella ellisii (14.0-37.8%) and unidentified fungus belonged to Atheliaceae (10.6-20.1%). These 3 fungal species accounted for almost all of the ECM abundance in each plot (94.9-99.8%). The remaining 5 fungal species were uncommon and rare. There was no clear difference in ECM fungal communities among plots. Community structure of ECM fungi in the young P. thunbergii plantation was simple and composed of fungal species that were also observed in mature coastal pine forests.