• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.2
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• pp.241-251
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• 1988

The purpose of this paper is to evaluate fracture strength of WA-vitrified and resinoid bond grinding wheels by means of acoustic emission. The paper conducts tension test, compression test, splitting tensile test and bending test with AE measuring system. These tests have been carried out in accordance with the grain sizes and grades of grinding wheels. The fracture strength of grinding wheels is evaluated by the clarification of biaxal fracture criterion of Babel and Sines. It clarifies the influence of factors of grinding wheel upon AE characteristics and evaluates the predictability of life of grinding wheels and the perception of fracture.

• Journal of the Korean Data and Information Science Society
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• v.9 no.2
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• pp.311-322
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• 1998

In this paper the problem of modeling count data where the observation period is determined by the survival time of the individual under study is considered. We assume marginal frailty model in the counts. We assume that the death times follow a Weibull distribution with a rate that depends on some covariates. For the counts, given a frailty, a Poisson process is assumed with the intensity depending on time and the covariates. A gamma model is assumed for the frailty. Maximum likelihood estimators of the model parameters are obtained. The model is applied to data set of patients with breast cancer who received a bone marrow transplant. A model for the time to death and the number of supportive transfusions a patient received is constructed and consequences of the model are examined.

• KSBB Journal
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• v.15 no.3
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• pp.274-279
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• 2000

A Saccharomyces cerevisiae isolated from a feed additive yeast product was cultivated in a Korean paper digestion wastewater in order to investigate the possibility of using it as substrate for the yeast. The yeast couldn't grow in the wastewater. It could grow in the wastewater diluted and the optimum dilution rate was 7.5 In batch cultivation with the jar fermenter the maximum total cell count was $1.34{\times}107/mL$ was obtained by the addition of undiluted digestion wastewater. By adding $(NH_4)_2S0_4 and KH_2P0_4$together with the undiluted wastewater the maximum cell concentration could be obtained faster.

• Journal of the Korean Society of Costume
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• v.59 no.6
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• pp.118-125
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• 2009

Goryeong Jeesandong tombs No.73 from the 5th century located in Gyeongsangbookdo is the most representative remains of the Daegaya. They were excavated and examined by the Daedong Research Center for Cultural Properties. In this study, the textiles in the Goryeong Jeesandong tomb No.73 is identified and their features are examined through scientific analysis. Due to the fact that the remains were not treated for preservation, we were able to observe many samples under the microscope. Within the hemp textiles both hemp and ramie were made using s-twist threads and the thread count distribution is calculated to be 8.0${\sim}$20.0/$cm^2$. Among the silk, the taffeta was categorized into five types. First, there was plain woven silk which the thickness of the warp and the weft is the same and their rate of threadcount was the same. The second type was thin tabby which is spacious between threads. The third kind was woven by warp and weft which had very different thickness. The fourth type used two threads for each warp. The fifth kind used two threads for the warp threads and used thick threads for the weft for a modified plain weave, and it is the first of its kind to be found. Also, there was a compound weave with warp-faced compound weave among silk.

• Korean journal of food and cookery science
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• v.26 no.5
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• pp.586-595
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• 2010

This study was conducted to examine the quality characteristics of tofu prepared with Lycii fructus powder(LFP) during storage for 15 days at $5{\pm}1^{\circ}C$. The moisture content, yield rate, tofu whey content and turbidity of soaking solutions of tofu prepared with LFP increased upon the addition of LFP. The pH of tofu prepared with LFP decreased while the acidity increased lightly; however, the acidity of the tofu did not differ significantly according to the level of added LFP. The L value of tofu decreased as the amount of LFP in the formulation increased, whereas the a and b values increased. The color value of tofu prepared with LFP did not depend upon the storage period. The hardness increased significantly with the level of LFP, but it did not differ significantly according to the storage period. The microbial count of tofu prepared with LFP was lower than that of control tofu during the storage period. In terms of overall preference, the preferred tofu contained 1.0% LFP tofu.

• Journal of Veterinary Clinics
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• v.17 no.1
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• pp.219-224
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• 2000

This study was conducted to examine the prognosis of canine pyometra after surgical treatment in terms of their clinical indications, hematology and serum chemistry. A total of 20 bitches diagnosed as pyometra after physical examination was hospitalized at the Veterinary Medical Teaching Hospital, Seoul National University, during the period of 1998 to 1999. After examining all profiles, ovariohysterectomy was performed to treat pyometra. All bitches had clinical symptoms of general depression, polyuria/polydipsia, anorexia and abdominal distension. In hematologic profiles, 65% of bitches had higher level of leukocyte count compared with normal level, but RBC and PCV values maintained within the normal ranges in most pyometric bitches. In serum chemistry profiler, ALT and ALP values were increased over the normal range, and BUN and creatine values were higher than normal ranges only in 10(50%) and 3 bitches (15%), respectively. Survival rate after ovariohisterectomy was 90% (18/20), but bitches that had higher ALT, ALP, BUN, creatine and potassium than normal values were died after surgical treatment. The results of this clinical investigation show that the recovery of pyometric bitches after ovariohysterectomy can be prognosed by hematologic and serum profiles including ALT, ALP, BUN, creatinine and potassium.

• Korean Journal of Microbiology
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• v.11 no.4
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• pp.175-180
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• 1973

This study was attempted to see more clear relationships among the enterobacteria, especially between the intestinal normal flora and pathogenic bacteria. It has been known that some intestinal normal flora produce the bactrial metabolites that are harmful to other enteric bacteria. One of the metabolites is known as colicin, the protein fraction, which possesses certain degree of inhibitory effect against other bacterial growth fraction, whih possesses certain degree of inhibitory effect against other bacterial growth. As a preliminary study for a colicin purification, the antagonistic effect of E, coli to groups of Salmonella and Shigella has been studied by means of in vitro quantitative culture method. 1. E.coli showed definite inhibitory effects aganist both Salmonella and Shigella groups in the mixture of two organisms. 2. The inhibitory effects of E.coli in the E.coli-Salmonella and the E.coli-Shigella mixture occurred from 4 hours incubation following the inoculation. 3. Even the complete inhibition of pathogenic enteric bacterial growth was noticed in the E.coli-Salmonella mixture at overnight incubation. 4. Among the diluted mixtures, 1:100, 1:1,000, and 1:10,000, survival rate of pathogenic enteric bacteria in the mixtures with E.coli showed least affected at the 1:1,000 dilution. 5. It was found that the antagonistic effect aganist groups of Salmonella-shigella was depending upon the groups of the genera.

• Biomedical Science Letters
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• v.1 no.1
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• pp.73-79
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• 1995

The effect of prior cumulative mixing was evaluated by means of a simple regression model which used as a dependent variable percentage(%) change of each repeated observed value for the initial value. The red blood cell count (RBC), hematocrit (Hct), and mean corpuscular volume(MCV) showed a significant decrease (p<.01), but % of basophils had a significant increase (p<.05). The ratios of rate of change (regression coefficient/SD) were .0012 for RBC, .0020 for Hct, .0024 for MCV, and .0011 for % of basophils. Of the 19 parameters evaluated, 21% changed.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1680-1681
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• 2011

In this paper, particle counting system using a CMOS image sensor is demonstrated. The system utilizes a linear photodetector array as a detection element. Therefore, the particles are detected by large detection region, in contrast to a single detector in conventional particle counting devices, while maintaining the sensitivity. The advantage of proposed system is that particles are detected in a relatively large area without using the particle focusing method. Also, proposed system can be easily integrated with a microfluidic chip by attaching the device underneath the bottom plate of the microfluidic chip. Detection of polystyrene microbeads has been tested at a flow rate of 4.89mm/s. For 21 measurements, proposed system showed an average count error of 7.29% and a standard deviation of 4.74%. Potentially, the proposed system can detect even smaller particles simply by utilizing a higher resolution CMOS image sensor.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1518-1521
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• 2008

Bacteria sense their population density and coordinate the expression of target genes, including virulence factors in Gram-negative bacteria, by the N-acylhomoserine lactones (AHLs)-dependent quorum sensing (QS) mechanism. In contrast, several soil bacteria are able to interfere with QS by enzymatic degradation of AHLs, referred to as quorum quenching. A potent AHL-degrading enzyme, AiiA, from Bacillus thuringiensis has been reported to effectively attenuate the virulence of bacteria by quorum quenching. However, little is known about the role of AiiA in B. thuringiensis itself. In the present study, an aiiA-defective mutant was generated to investigate the role of AHA in rhizosphere competence in the root system of pepper. The aiiA mutant showed no detectable AHL￢-egrading activity and was less effective for suppression of soft-rot symptom caused by Erwinia carotovora on the potato slice. On the pepper root, the survival rate of the aiiA mutant significantly decreased over time compared with that of wild type. Interestingly, viable cell count analysis revealed that the bacterial number and composition of E. carotovora were not different between treatments of wild type and the aiiA mutant. These results provide evidence that AHA can play an important role in rhizosphere competentce of B. thuringiensis and bacterial quorum quenching to Gram-negative bacteria without changing bacterial number or composition.