• Journal of the Korean Institute of Landscape Architecture
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• v.17 no.3
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• pp.35-47
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• 1990

This study was executed to analyze the vegetational landscape structure and administration planning of Heonin Royal Tomb forest by three kinds of ordination techniques (PCA, RA and DCA) and comparison of the couple photographs between 1920s and 1980s. Seventeen sites in the recreation area and fifteen sites in the protective area were sampled with clumped sampling method in June 1988 and five quadrats were examined in each site. Environmental impact grade 3, 4 and 5 area covered 56.4% of the surveyed area and these area should be restored by the input of human energy. Pinus densifora community of actual vegetation covered 8.4%, Alnus japonica 24.2% and Quercus community 40.9% of the total area. And the afforested vegetation of Pinus koraiensis and Pinus rigida covered 23.1 % The recreation area was divided by P. densiflora, P. densiflora-Quercus aliena, A. japonica-Q.aliena, A. japonica and the protective area by Q. acutissima, Q. aliena, A. japonica-Q. aliena.. DCA ordination showed that successional trends of tree species seem to be from P. densiflora, Sorbus alnifolia, Styrax obassia to Q. variabilis Q. serrata in P. densiflora community and from A. japonica through A. ginnala to Q. aliena in A. japonica community of the upper layer. By the comparison of the couple photographs between 1920s and 1980s, we can recognize the change of historical landscape composed of P. densiflora community and those community is succeeded to Q. aliena.

• Journal of Ecology and Environment
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• v.41 no.3
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• pp.66-71
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• 2017

Background: The sprouts of oak species play an important role in maintaining the oak community in a disturbed environment. In this study, we cut 1-year-old oak in three times during the 3 years and measured the sprout responses to know sprouting ability of six deciduous oaks in Korea. Results: Oak sprouts have appeared in spring and fall, and some of the sprouts had lifespan as short as a month. As the number of cutting increases, sprout number of Quercus acutissima increased whereas the other oak species decreased or died. The average number of sprouts over the 3 years was from 1.4 (Quercus mongolica) to 2.2 (Q. acutissima) per individual. Quercus serrata died after the second cutting, and Quercus dentata died after the third cutting. So, the two species have the lowest sprouting ability among six oak species. The sprouts grew actively during fall and slowly in summer. The sprout length during the 3 years was in the following descending order: Q. acutissima, Quercus aliena, Q. dentata, and Q. mongolica. Sprout of Q. acutissima and Q. aliena generated steadily over the 3 years, and sprout of Quercus variabilis and Q. mongolica was changed by year. After the 3 years, the number of sprouts increased only in Q. acutissima but sprout number of the other five oak species decreased. The sprout length of Q. acutissima, Q. aliena, and Q. variabilis increased, but sprout length of the other three oak species decreased. The average survival rate of saplings over the 3 years was in the following descending order: Q. acutissima, Q. aliena, Q. variabilis, and Q. mongolica. Conclusions: As a result, the sprouting ability of Q. acutissima was the highest. Such level of sprouting ability may be the evidence of how Q. acutissima community exists as a dominant species in a disturbed environment in lowlands of Korea peninsula.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.4
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• pp.895-899
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• 2000

A method of measuring Q of a two port cavity by scattering parameters is proposed. The scattering parameters of a two port cavity resonator are derived by a lumped equivalent circuit model as a function of cavity parameters, including the cavity Q. These can be also obtained by direct measurement with a modern network analyzer, The results show good agreement with those from other well-known methods. This two port measurement can provide additional information such as the coupled power ratio, which is one of the important parameters for the beam accelerating cavities.

• Journal of the Korean Mathematical Society
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• v.45 no.4
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• pp.977-991
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• 2008

We characterize the boundedness and compactness of the weighted composition operator $uC_{\psi}$ from the general function space F(p, q, s) into the logarithmic Bloch space ${\beta}_L$ on the unit disk. Some necessary and sufficient conditions are given for which $uC_{\psi}$ is a bounded or a compact operator from F(p,q,s), $F_0$(p,q,s) into ${\beta}_L$, ${\beta}_L^0$ respectively.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.3
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• pp.1-6
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• 2008

A dual band I/Q modulator which converts baseband input signals to 2.4GHz or 5GHz RF output has been proposed. The dual band I/Q modulator for 2.4GHz and 5GHz wireless LAN applications consists of $90^{\circ}$ phase shifter and wideband mixer. The I/Q modulator showed 15dB conversion loss at 2.4GHz and 16dB conversion loss at 5GHz. The sideband suppression is about 15dBc at 2.4GHz and 16dBc at 5GHz. Measured data shows 8.5% EVM at 2.4GHz, and 10% EVM at 5GHz for QPSK with symbol rate of 11Mbps. A carrier rejection is about 40dBc at 2.4GHz/5GHz band, and the I/Q modulator satisfied the output wireless LAN spectrum mask with baseband input signal.

• Journal of Nutrition and Health
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• v.37 no.4
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• pp.329-338
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• 2004

The purposes of this study were to : a) develop the quality assessment tool of hospital foodservice management, b) evaluate the S hospital's foodservice quality by this tool, and c) do the feasibility study about this tool in hospital food-service field by establishing quality management strategies. The developed quality assessment tool of hospital food-service management was consisted of 20 items for quality evaluation by Likert 5 point scale and two additional questions with the most satisfactory item and the most unsatisfactory item. As a result of evaluation, S hospital's foodservice quality was somewhat high, on the factor 'personnel attitude', especially. The IPA technique proved nine items including Q5, Q7, Q8, Q11, Q12, Q13, Q15, Q16, Q17 were in 'Doing Great, Keep It Up' and seven items such as Q1, Q2, Q3, Q6, Q9, Q18, Q19 that got high expectation and low perception needed to be focused in quality management strategy.

• Honam Mathematical Journal
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• v.17 no.1
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• pp.7-14
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• 1995

The purpose of this study is to construct the structure of the connected Lie group G with its Lie algebra $g=rad(g){\oplus}sl(2, \mathbb{F})$, which conforms to Stellmacher's [4] Pushing Up. The main idea of this paper comes from Stellmacher's [4] Pushing Up. Stelhnacher considered Pushing Up under a finite p-group. This paper, however, considers Pushing Up under the connected Lie group G with its Lie algebra $g=rad(g){\oplus}sl(2, \mathbb{F})$. In this paper, $O_p(G)$ in [4] is Q=exp(q), where q=nilrad(g) and a Sylow p-subgroup S in [7] is S=exp(s), where $s=q{\oplus}\{\(\array{0&*\\0&0}\){\mid}*{\in}\mathbb{F}\}$. Showing the properties of the connected Lie group and the subgroups of the connected Lie group with relations between a connected Lie group and its Lie algebras under the exponential map, this paper constructs the subgroup series C_z(G)

• Journal of dental hygiene science
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• v.14 no.4
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• pp.468-476
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• 2014

The aim of this study was to examine whether there is an association between vitamin intakes and established periodontitis in Korean adult population. The 6,245 subjects aged over 19 years old, who participated in health survey, oral examination and nutrition survey were selected for this study from the database of the Fourth Korean National Health and Nutrition Examination Survey. Established periodontitis was defined as ${\geq}$ code 3 in community periodontal index. Vitamin intake was assessed with the food-frequency questionnaire. In analysis, participants were classified by quintile of vitamin intakes. We also considered covariates as socio-demographic characteristics, health-related behaviors including physical activities, systemic diseases and oral health-related behaviors. Multiple logistic regression was performed to assess the crude and adjusted associations. All analyses considered a complex sampling design using SAS 9.2. In crude analysis, less intake of vitamin A, retinol and vitamin B2 significantly increased the risk of periodontitis (vitamin A, odds ratio [OR] Q1=1.00, Q2=0.73, Q3=0.80, Q4=0.77, Q5=0.78; retinol, OR: Q1=1.00, Q2=0.86, Q3=0.73, Q4=0.62, Q5=0.55; vitamin B2, OR: Q1=1.00, Q2=0.70, Q3=0.63, Q4=0.67, Q5=0.68). However, after adjusting for socio-demographics, general and oral health status and behaviors, only vitamin B2 was significantly associated with established periodontitis (OR: Q1=1.00, Q2=0.72, Q3=0.73, Q4=0.76, Q5=0.84). An adequate vitamin B2 intake was significantly associated with a decreased risk of periodontitis. This finding shows that nutrient intake is slightly correlated with periodontitis in Korean adult population. Further studies are needed to understand this association between nutrients intake and periodontitis in more details.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.3
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• pp.385-389
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• 2014

Flavonols as a major kind of plant secondary metabolites are known for health-promoting compounds in onions (Allium cepa L.). The objectives of this study are to determine profiles of flavonol glycosides in different 75 onion accessions. A total of five flavonols (quercetin 3,4'-diglucoside, Q34'diG; quercetin 3-glucoside, Q3G; quercetin 4'-glucoside, Q4'G; isorhamnetin 4'-glucoside, I4'G; quercetin, Q) were identified from onion accessions. In positive ion mode using LC-ESI-MS, individual flavonols were confirmed from one and two glycosylation binding with aglycone such as quercetin and isorhamnetin. Total flavonol contents were distributed in white onion (range of 0.18-6.47 mg/g DW) and purple onion accessions (range of 2.39-6.47 mg/g), respectively. The mean of flavonol contents in purple onion (4.41 mg/g) showed 1.4-fold higher than white onion (3.23 mg/g). The Q34'diG and Q4'G were considered as the major compounds of flavonol glycosides in onion accessions.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.4A
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• pp.325-328
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• 2011

In this paper, we present a new and simple derivation of the Craig representation for the two-dimensional (2-D) Gaussian Q-function in the viewpoint of geometry. The geometric derivation also leads to an alternative Craig form for the 2-D Gaussian Q-function. The derived Craig form is newly obtained from the geometry of two wedge-shaped regions generated by the rotation of Cartesian coordinates over two correlated Gaussian noises. The presented Craig form can play a important role in computing the probability represented by the 2-D Gaussian Q-function.