• Communications for Statistical Applications and Methods
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• v.17 no.4
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• pp.515-525
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• 2010

We investigated design-based properties of the ordinary least square estimator(OLSE) and the weighted least square estimator(WLSE) in a panel regression model. Given a complex data we derive the magnitude of the design-based bias of two estimators and show that the bias of WLSE is smaller than that of OLSE. We also conducted a simulation study using Korean welfare panel data in order to compare design-based properties of two estimators numerically. In the study we found the followings. First, the relative bias of OLSE is nearly two times larger than that of WLSE and the bias ratio of OLSE is greater than that of WLSE. Also the relative bias of OLSE remains steady but that of WLSE becomes smaller as the sample size increases. Next, both the variance and mean square error(MSE) of two estimators decrease when the sample size increases. Also there is a tendency that the proportion of squared bias in MSE of OLSE increases as the sample size increase, but that of WLSE decreases. Finally, the variance of OLSE is smaller than that of WLSE in almost all cases and the MSE of OLSE is smaller in many cases. However, the number of cases of larger MSE of OLSE increases when the sample size increases.

• 주택과사람들
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• s.220
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• pp.34-36
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• 2008

지난 8월 21일, 부동산 관련 세제 완화안이 발표됐다. 하지만 발표된 내용만으로는 시장을 만족시키지 못해 세제 추가 완화가 예상되고 있다. 현재까지 논의되고 있는 세제 개편 방향과 시장의 요구를 살펴보고, 한나라당 등이 국회에서 발의한 부동산 세제 개정안을 짚어보자

• The Monthly Diabetes
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• s.132
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• pp.94-95
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• 2000

단무는 무의식상태에서 기운을 타고 춤을 추며 몸의 혈과 경락을 열어주고 몸에 진기를 발생시키는 것이다. 단무를 추면 막혔던 경락이 뚫리고 굳어 있던 근육이 풀리면서 마음의 평화와 기쁨을 얻을 수 있다.

• Korean Journal of Plant Taxonomy
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• v.47 no.1
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• pp.27-45
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• 2017

A taxonomic study of the genus Hosta (Lilliaceae) in Korea was conducted based on morphological characteristics. Hosta clausa varieties share several characteristics (rhizomes with underground stolons, smooth scapes, and purple anthers). Hosta clausa var. normalis has an open perianth, long pistils, and fertile fruit. H. clausa var. clausa can be distinguished from H. clausa var. normalis by its closed perianth and sterile fruit. H. clausa var. geumgangensis has sterile fruit, green petioles, short pistils, and short narrow perianth tubes. H. clausa var. ensata has very narrow, sword-shaped leaves. It can be included in H. clausa var. normalis, which has a large degree of variation in leaf and petiole shape. H. jonesii has smooth scapes, yellow anthers, and bell-shaped flowers. It can be distinguished from the related species H. tsushimensis found on the Tushima islands in Japan by its wide perianth tube. H. yingeri is distinguished by its funnel-shaped flowers, 3 long and 3 short stamens, and smooth scape; the related species H. laevigata has 6 equally-sized stamens, narrowly lanceolate leaves, and wavy leaf margins. Because H. laevigata is not found in its type locality Isl. Heugsando, its taxonomic position must be determined at a later time. H. minor shares several characteristics (scapes with ridges and yellow-colored anthers) with the related taxa H. venusta. However, H. venusta is changed to H. minor var. venusta because it has overlapping characteristics in plant size, number of flowers, leaf size, and leaf shape. Consequently, the genus Hosta in Korea is classified into 5 species, 3 varieties, and 6 forms.

• The KIPS Transactions:PartB
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• v.10B no.5
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• pp.575-578
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• 2003

SPIHT algorithm is a wavelet based fast and effective technique for image compression. It uses a list structure to store status information which is generated during set-partitioning of zero-tree. Usually, this requires lots of additional memory depending on how high the bit-rate is. Therefore, in this paper, we propose a new technique called MZP-DFS, which needs no additional memory when running SPIHT algorithm. It traverses a spatial-tree according to DFS and eliminates additional memory as it uses test-functions for encoding and LSB bits of coefficients for decoding respectively. This method yields nearly the same performance as SPIHT. This may be desirable in hardware implementation because no additional memory is required. Moreover. it exploits parallelism to process each spatial-tree that it can be applied well in real-time image compression.

• Journal of the Korean Data and Information Science Society
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• v.21 no.4
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• pp.737-745
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• 2010

In this paper, various methods for finding confidence intervals for the p of binomial parameter are reviewed. We compare the performance of several confidence interval estimates in terms of actual coverage probability by small sample Monte Carlo simulation.

• The Korean Publising Journal, Monthly
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• s.139
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• pp.14-15
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• 1993

일본인들은 한국.한국인들을 어떻게 보고 있는가. 최근 파문을 일으키고 있는 "추한 한국인" 사건은 새삼 이런 물음을 던져보게 한다. 때마침 구한말 일본들이 쓴 한국에 관한 책 두권이 번역되었고, 기자.유학생.시인.작가 등 다양한 일본인들이 한국을 경험한 이야기를 책으로 출간했다. 그 속에 나타난 우리는.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.482-489
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• 1996

Dried-red pepper, whole and powdered types, was subjected to a storage-study by investigation the effects of packaging methods (polycloth & polyethylene/polycloth, whole dried-red pepper; nylon/polyethylene-lam-inated film, red pepper powder), temperature (ambient, $5{\sim}10^{\circ}C$) and gamma irradiation doses (0-10 kGy). After 6 months storage in polyclith sack at ambient temperature, all whole dried-red pepper showed quality deterioration, such as weight change, insect infestation, discoloration and chemical changes, After 2 years storage in combined packaging with polyethylene/polycloth sack of 5-7.5 kGy irradiated whole dried-red pepper at ambient temperature, however, quality deterioration was not observed. Gamma-irradiated red pepper powder (7.5-10kGy) showed a good quality in hygienic, physicochemical and organoleptic evaluation after 2 years of storage at ambient temperature.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.932-937
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• 2007

Quality evaluation and hazard management of lettuce (Lactuca sativa L.) which was prepared within the harvesting seasons were analyzed. Eatable weight was highest in the summer (953.40 g)>spring (912.27 g)>fall (895.28 g) lettuce, but sugar content showed the highest concentration in the spring. Total color of summer lettuce was the brightest in comparison with other seasons. Fall lettuce's color increased in yellowness more than greenness. Minerals of lettuce were abundant in the following order of K>Ca>Na>Mg>Fe in all seasons. Chlorophyll content, showing the similar trend to vitamin C, was the lowest in summer. Among the 48 different pesticides tested, only chlorthalonil was detected in a minute content from fall lettuce. In conclusion, summer lettuce was inferior to spring and fall in quality because of hot weather.

• Korean Journal of Plant Resources
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• v.32 no.1
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• pp.53-62
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• 2019

The purpose of this study was to establish the in vitro propagation system by shoot tip culture of six Hosta species native to Korea (Hosta capitata (Koidz.) Nakai, H. clausa Nakai, H. jonesii M.G.Chung, H. minor (Baker) Nakai, H. venusta F.Maek., and H. yingeri S.B.Jones) for mass proliferation and a new cultivar development. The shoot tips of each Hosta species were cultured on MS medium containing eight combinations of 0.5, 1.0, 2.0, 4.0 mg/L BA with 0.1 mg/L NAA, 0.1, 0.5, 1.0, 2.0 mg/L TDZ with 0.1 mg/L NAA, and without any PGRs (control). They were investigated on callus, somatic embryo, crown bud, differentiation and growth of shoot and root, total fresh weight after 8 weeks of culture. In all six Hosta species, callus and somatic embryo induction rate and multiple shooting rate of the PGRs treatment group were higher than that of the control group. The highest number of differentiated shoots were obtained on medium supplemented with 2.0 ㎎/L TDZ in H. capitata (5.4), 1.0 mg/L TDZ in H. clausa and H. jonesii (3.3 and 5.8, respectively), 0.5 mg/L BA in H. minor (11.1), 1.0 mg/L BA and 0.1 mg/L TDZ in H. venusta (8.1), and 0.5 mg/L TDZ in H. yingeri (9.8). In somatic embryo formation, the PGRs treatment group of H. jonesii and H. yingeri were more effective than the control group, and the effects were relatively less in H. capitata, H. clausa Nakai, H. minor, H. venusta. Crown bud formation of four Hosta species (H.capitata, H. clausa, H. jonesiig, and H. yingeri) were also higher in the PGRs treatment group than in the control group. Crown bud formation of four Hosta species (H.capitata, H. clausa, H. jonesiig, and H. yingeri) were also higher in the PGRs treatment group than in the control group. H. clausa showed no significant effect on callus and shoot differentiation regardless of the type and concentration of cytokinin, but slightly increased in formation of crown bud in TDZ.