• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.35.1-35.1
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• 2017

We present the characteristics and the performance of the new CCD camera system, SNUCAM-II (Seoul National University CAMera system II) that was installed on the Lee Sang Gak Telescope (LSGT) at the Siding Spring Observatory Australia in 2016. SNUCAM-II consists of a deep depletion chip covering a wide wavelength from $0.3{\mu}m$ to $1.1{\mu}m$ with high sensitivity (QE at 90%). It is equipped with SDSS ugriz filters and 13 medium band width (50nm) filters. On LSGT, SNUCAM-II covers $15.7{\times}15.7arcmin$ FOV at pixel scale of 0.92 arcsec and a limiting magnitude of g = 19.91 AB mag at $5{\sigma}$ with 180s exposure time. SNUCAM-II will enable us to study Spectral Energy Distributions (SEDs) of diverse objects from extragalactic sources to solar objects in the southern hemisphere for research and education activities.

• Journal of the Korean Ceramic Society
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• v.23 no.3
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• pp.62-66
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• 1986

Mechanical properties of $Al_2O_3$ based composite ceramics reinforced by SiC whiskers up to 40% by volume we-re investigated. Specimens were hot pressed at $1, 500^{\circ}C$ under 28.5MPa for 30min in Ar atmosphere. Porosities room temperaturefracture toughnesses and flexural strengths up $1, 000^{\circ}C$ were measured. Porosities were increa-sed as the SiC whisker cortent increased. After compensating the effect of porosities that means extrapolated in zero porosities the reinforced composites exhibited increases in flexural strength and fracture toughness as the whi-sker content increased, .

• Biomedical Science Letters
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• v.11 no.3
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• pp.295-299
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• 2005

Staphylococcus aureus is an important animal and human pathogen implicated in a variety of disease including food-poisoning caused by staphyloccal enterotoxins (SEs). In order to investigate the difference in genomic types and to monitor the transmission of S. aureus isolates, a total of 25 S. aureus isolates from different sources were determined for their genotypic characteristics by pulsed-field gel electrophoresis (PFGE) in addition to their ability to enterotoxin production and antibiotic resistance patterns in this study. All the isolates were susceptible to amikacin, and the resistance pattern to ampicillin and penicillin were most common among 14 different patterns. Eleven of 24 isolates produced one of three SEs, SEA, SEC or SED. Sixteen representative PFGE patterns were obtained by Smal restriction fragments of S. aureus isolates. Analysis of dendrogram based on PFGE band patterns suggested that food-poisoning outbreaks be caused by the diverse sources of food, of which their raw materials were infected with S. aureus. Also, it could be concluded that PFGE was a powerful tool for epidemiological tracing of infection source for food-initiated outbreaks.

• Journal of the Korean Operations Research and Management Science Society
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• v.15 no.2
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• pp.33-44
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• 1990

An efficient algorithm is developed for the linear programming relaxation of generalized multiple choice knaspack problem. The generalized multiple choice knaspack problem is an extension of the multiple choice knaspack problem whose relaxed LP problem has been studied extensively. In the worst case, the computational coimplexity of the proposed algorithm is of order 0(n. $n_{max}$)$^{2}$), where n is the total number of variables and $n_{max}$ denotes the cardinality of the largest multiple choice set. The algorithm can be easily embedded in a branch-and-bound procedure for the generalized multiple choice knapsack problem. A numerical example is presented and computational aspects are discussed.sed.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.344-348
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• 2011

본 연구에서의 낙동강 본류에 설치예정인 N보를 중심으로 수문조건에 따른 흐름특성을 연구하기 위하여 N수위표에서 상류방향으로 약 4km구간을 채택하였다. 분석에서는 수위표 상류 약2.5km지점에 보를 설치하여 수문의 개방도와 수문조건에 따라 보의 상 하류 구간의 수리학적 특성 및 하상변화의 분석을 실시하였다. 그 결과 유속 수심 및 하상변동은 보에서 배수되는 유량과 밀접한 관계가 있다고 판단되며 차후 유황에 따른 수문의 개방도를 적절히 계획 설계하여 보다 안정적인 치수계획을 수립해야 할 것으로 판단된다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.5
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• pp.411-417
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• 1990

To compare the dietary and urinary minerals with serum lipid and minerals this study was carried out on 30 rural housewives in Kyunggi area. Mean intake of energy was 1770.3Kcal and protein 55.5g per day. Mineral intakes per day were measured; sodium 4330mg phos-phorus 485.7mg calcium 388.0mg zinc 8.99mg and copper 2.23mg Urinary minerals were analy-sed ; sodium 4379mg phosphorum 371.3mg calcium 190.0mg zinc 328.0mg and copper 49.6mg. Serum contents of lipid and minerals were : cholesterol 169.0mg% triglyceride 70.6mg% $\beta$-lipoprotein 304.9mg% sodium 142.3mM phosphorus 3.94mg% calcium 9.06mg% zinc 1215.7 ppb and cooper 620.0ppb. Eietary sodium and zinc urinary copper were significantly related with serum lipids.

• Journal of Fashion Business
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• v.13 no.2
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• pp.145-153
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• 2009

By introducing chitosan treatment prior to dyeing, examination was given to the effect of chitosan coated on the surface of fabrics on the color change of dyed fabric based on th e change of ${\Delta}E$, a*, and b* values. At the same time, the dyeing mechanism of Caesalpinia sappan dyestuff was predicted by the investigation of the change of air-permeability ac cording to the chitosan treatment. The change of elution was investigated by the examination of the elution of metallic ions employed as mordants after soaking dyed fabrics in the solution of alkaline perspiration ba sed upon the fact that chitosan carries excellent absorption ability toward metallic ions.

• Journal of Mechanical Science and Technology
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• v.15 no.10
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• pp.1398-1407
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• 2001

In this paper an anti-lock brake system (ABS) for commercial buses is proposed based on a fuzzy-logic controller and a sliding-mode observer of the vehicle speed. The brake controller generates pulse width modulated (PWM) control inputs to the solenoid valve of each brake, as a function of the estimated wheel slip ratio. PWM control inputs at the brakes significantly reduce chattering in the brake system compared with conventional on-off control inputs. The sliding-mode observer estimates the vehicle speed with measurements of wheel speed, which is then sed to compute the wheel slip ratio. The effectiveness of the proposed control algorithm is validated by a series of computer simulations of bus driving, where the 14-DOF bus model is used.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1012-1013
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• 2006

A technology of hardening porous materials of titan powders has been elaborated. The technology is based on passing alternating current with duration of ${\sim}10^{-1}{\ldots}10^1$ s through porous ($35{\ldots}40%$) blanks made by method of Sintering by Electric Discharge (SED) by passing a pulse of current with duration of ${\sim}10^{-5}{\ldots}10^{-3}$ s. The influence of technological regimes of porous blanks treatment on their structure and properties is investigated. Geometry and dimension of contact necks between powder particles of obtained samples are evaluated. Variations of porosity and strengths as well as microstructure of porous samples materials before and after treatment are investigated. Optimum range of treatment technological regimes is determined within which porosity of $30{\ldots}35%$ with maximum strength values.

• Journal of the Korea Safety Management & Science
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• v.10 no.1
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• pp.191-195
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• 2008

The present study contributes reviewing and suggesting various models for measurement system analysis (MSA). Measurement errors consist of accuracy, linearity, stability, part precision, repeatability and reproducibility (R&R). First, the major content presents split-plot design, and the combination method of crossed and nested design for obtaining gage R&R. Second, we propose $\bar{x}-s$ variable control chart for calculating the gage R&R and number of distinct category. Lastly, investigating the determination of gage performance curve which establishes the control specification propagating calibration uncertainties and measurement errors is described.