• Journal of The Korean Astronomical Society
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• v.37 no.5
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• pp.439-446
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• 2004

A critical discussion of our knowledge about extragalactic cosmic rays and magnetic fields is at-tempted. What do we know for sure? What are our prejudices? How do we confront our models with the observations? How can we assess the uncertainties in our modeling and in our observations? Unfortunately, perfect answers to these questions can not be given. Instead, I describe efforts I am involved in to gain reliable information about relativistic particles and magnetic fields in extragalactic space.

• Honam Mathematical Journal
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• v.32 no.1
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• pp.91-99
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• 2010

In this paper we introduce the concept of asymptotically almost negatively associated random variables in a Hilbert space and obtain the strong law of large numbers for a strictly stationary asymptotically almost negatively associated sequence of H-valued random variables with zero means and finite second moments. As an application we prove a strong law of large numbers for a linear process generated by asymptotically almost negatively random variables in a Hilbert space with this result.

• Journal of applied mathematics & informatics
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• v.6 no.2
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• pp.487-502
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• 1999

The hydrodynamic flow between two eccentric cylinders is examined for small values of modified Reynolds number porosity parameter and the non-dimensional slip velocity parameter in the presence of a radial magnetic field. The stream function and the pres-sure distribution are calculated and the results are presented graph-ically.

• Bulletin of the Korean Mathematical Society
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• v.32 no.2
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• pp.179-189
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• 1995

Let $V \subset R^n$ be a convex homogeneous cone which does not contain straight lines, so that the automorphism group $$ G = Aut(R^n, V)^\circ = { g \in GL(R^n) $\mid$ gV = V}^\circ $$ ($\circ$ denoting the identity component) acts transitively on V. A convex cone V is called "self-dual" if V coincides with its dual $$ (1.1) V' = { x' \in R^n $\mid$ < x, x' > > 0 for all x \in \bar{V} - {0}} $$ where $\bar{V}$ denotes the closure of V.sure of V.

• Korean Journal of Clinical Pharmacy
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• v.3 no.1
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• pp.55-60
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• 1993

For prevention of hospital infection, selection of adequate disinfectants by clinical pharmacist is very important role in hospital pharmacy and for performing this role, pharmaceutical, chemical and microbial knowledge of disinfectants and nosocomial microorganism are required to hospital pharmacists. Therefore, to make sure of guideline for choice of disinfectants, author clarifies the distinctive character of disinfectants which are supplied to clinical departments and wards from hospiatal pharmacy in Korea and arrange the specific attention for use of each disinfectants

• Communications of Mathematical Education
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• v.20 no.4 s.28
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• pp.575-586
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• 2006

Both theory and experiment are very important parts in sciences. Especially in mathematics, theory seems to be very important, but experiment or practice doesn't. Numerical analysis of many parts in mathematics needs practice in computer. In this paper, I suggest that computer-practicing in teaching power method, inverse power method and deflation to calculate eigenvalues and eigenvectors is good in understanding the theory. It also makes students sure that mathematics is helpful.

• Journal of the Korean Statistical Society
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• v.33 no.1
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• pp.99-106
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• 2004

Let {X, $X_{n}, n\;{\geq}\;1$} be a sequence of identically distributed, negatively associated (NA) random variables and assume that $│X│^{r}$, r > 0, has a finite moment generating function. A strong law of large numbers is established for weighted sums of these variables.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.1-9
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• 2001

The objectives of this study were to explain market structures of logs imported to Korea from U.S.A., New Zealand. Chile. The demand for imported logs is modeled as a function of output of wood manufacturing in Korea and log prices of competing suppliers. It is hypothesized that the quantity of log impaled in a period is determined by its own and competing prices and the output of wood corresponding manufacturing sector in the current period. Import demand functions of logs imported to Korea from U.S.A., New Zealand and Chile were estimated by SURE(Seemingly Unrelated Regression Equations). Elasticities of amounts of logs imported to Korea from U.S.A., New Zealand and Chile with respect to price of imported log from U.S.A. were -2.88, 1.36 and 3.17, respectively. Elasticities of amounts of logs imported to Korea from U.S.A., New Zealand and Chile with respect to price of imported log from New Zealand were 0.71, -1.65 and 1.44, respectively, Elasticities of amounts of logs imported to Korea from U.S.A., New Zealand and Chile with respect to price of imported log from Chile was -2.88. 1.36 and 3.17.

• Tuberculosis and Respiratory Diseases
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• v.71 no.4
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• pp.249-253
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• 2011

Background: Mycobacterial infection is a problem throughout the world along with the increase of immunocompromised patients. For this reason, there have been many methods for faster and more accurate diagnosis. In this study, we evaluated several laboratory methods for mycobacterial infection. Methods: From January to December 2009, 635 specimens were cultured with mycobacteria growth indicator tube (MGIT) and Ogawa media. Polymerase chain reaction (PCR) was performed with the AdvanSure tuberculosis (TB)/non-tuberculosis mycobacterium (NTM) real-time PCR Kit (LG Life Sciences, Seoul, Korea). The 69 samples showing positive culture results were identified with the AdvanSure Mycobacteria Genotyping Chip Kit (LG Life Science, Seoul, Korea). Results: Sixty-nine (10.9%) out of 635 samples showed positive results for mycobacterial culture. Among the 635 samples, 64 were positive in MGIT, but only 42 were positive in Ogawa media. Of the 635 samples, 607 (95.6%) showed the same results between MGIT and Ogawa and the results of 579 (95.4%) were also consistent with the TB/NTM real-time PCR results. However, in the case of NTM, only one (1/24, 4.2%) was positive in PCR. In the Mycobacteria genotyping chip analysis, the most frequently identified NTM species in descending order were M. avium, M. intracellulare, M. chelonae and M. abscessus. Conclusion: Culturing with a combination of MGIT and Ogawa is recommended to increase the recovery rate of mycobacteria. Although PCR missed a reasonable number of NTM, it is faster and usually gives results that concur with those from the culture. The appropriate combination of diagnostic methods with clinical correlation are necessary.

• Biomedical Science Letters
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• v.15 no.1
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• pp.47-53
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• 2009

Urinary bladder cancer is diagnosed through urine cytology and cytoscopy with biopsy. An atypical urothelial cast is often found by voided urine cytology in a papillary urothelial cell carcinoma. The objective of this study is to demonstrate the significance of the evaluation of urinary nuclear matrix protein (NMP22) level and Sure Path Liquid-based cytology (SP-LBC) as compared to the examination of atypical urothelial cast in voided urine sediment for monitoring bladder cancer. From October 2007 to January 2008, we observed 3240 patients who visited the emergency laboratory of urology of Soonchunhyang University, Cheonan Hospital. Both NMP22 measurement and SP-LBC were performed in 31 patients who were positive in an atypical urothelial cast test. In particular, 26 men and 5 women were found to be atypical urothelial cast-positive persons. The average age for both men and women is 61.8. NMP22 test is positive in 23 of 31 cases (74.2%) from patients with atypical urothelial cast, while the test is negative in 8 of 31 cases (25.8%). The percentages of negativity, atypicality, suspicious malignancy, and malignancy in SP-LBC are 25.8% (8/31), 58.1% (18/31), 9.7% (3/31), and 6.5% (2/31), respectively. The relation of NMP22 positivity with the malignant degree in LBC is significant (P<0.01). Two malignant patients resulting from SP-LBC show the same results in histological examination. Overall, the study suggests the usefulness of NMP22 measurement and LBC as well as the examination of atypical urothelial cast for the diagnosis of early bladder cancer.