• Journal of Korean Institute of Industrial Engineers
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• v.24 no.3
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• pp.333-343
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• 1998

This paper proposes variable stream and sample size(VSSS) group control charts in which both the number of streams selected for sampling and sample size from each of the selected streams are allowed to vary based on the values of the preceding sample statistics. The proposed charts select a small portion of streams and take samples of size n = 1 if both the largest and smallest of sample means fall between the lower and upper threshold limits, and select a large portion of streams and take samples of size n > 1 otherwise. A Markov chain approach is used to derive the formulas for evaluating the performances of the proposed charts. Numerical comparisons are made between the VSSS and fixed stream and sample size(FSSS) group control charts.

• Bulletin of the Korean Chemical Society
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• v.16 no.7
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• pp.588-591
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• 1995

Single crystals of (ZnSe)1-x(CuMSe2)x (M=Al, Ga, or In) were grown by chemical vapor transport technique. Powdered polycrystalline samples of (ZnSe)1-x(CuMSe2)x (M=Al, Ga, or In) were also prepared by the direct combination of the elements. The chemical composition of these single crystals was determined by comparing their lattice parameters with those of the standard polycrystalline samples. The IR transmission range of single crystals of (ZnSe)1-x(CuMSe2)x (M=Al, Ga, or In) is slightly narrower than that observed for pure ZnSe. However, these materials still show good transmission in the long-wavelength IR range. The addition of small amounts of CuMSe2 (M=Al, Ga, or In) considerably increases the hardness of ZnSe.

• East Asian Journal of Business Economics (EAJBE)
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• v.9 no.1
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• pp.17-26
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• 2021

Purpose-This study examines how financial slack resources and subcontracting of small and medium-sized enterprises (SMEs) affect their internationalization. To identify slack resources, subcontracting, and internationalization of SMEs, 1,062 SME samples in the electronics industry are used in the logistic regression analysis to analyze their relationship with SMEs' export. Research design, data, and methodology-This study conducted the empirical analysis on 1,062 SMEs in the electronics industry using the sample survey method. The samples were based on data selected and distributed by the Ministry SMEs and Startups. The data analysis methods were descriptive, correlation analysis, and logistics regression analysis. Result-The analysis shows that only available resources are negatively related to SMEs' internationalization. It can be interpreted as a high tendency for SMEs to avoid relatively risky choices such as entering overseas markets if they have enough financial resources. Moreover, subcontracting has a negative relationship with internationalization. Conclusion-This study broadened the scope of SME research by analyzing subcontracting and slack resources together and provides practical implications for policymakers and managers.

• Food Science of Animal Resources
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• v.25 no.1
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• pp.1-6
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• 2005

To evaluate the microbiological quality of pork carcasses at different slaughtering process in large and small scale slaughtering houses, swabbing method was used to analyze microorganisms on the surface of pork belly in each process of before evisceration, after evisceration, before final wash, after final wash and in chilling. In autumn time, large scale slaughterhouse showed lower incidence of aerobic microorganisms (10²∼10³ CFU/㎠) than those of small scale slaughterhouse (10⁴∼10/sup 5/ CFU/㎠) during all processing lines. Samples from cold room of large scale slaughterhouse showed lower incidence of aerobic cells (10² CFU/㎠) than small scale slaughterhouse (10⁴ CFU/㎠). In winter and spring time, large scale slaughterhouse showed lower incidence of aerobic microorganisms than those of small scale slaughterhouse during the slaughtering process of before evisceration, after evisceration and before final wash, except spring samples from before final wash and chilling at cold room storage in spring time. After final wash, different sampling place of carcass such as belly, ham, jowl showed the different washing effect depending on the small and large scale slaughterhouse. After final wash, ham and belly had lower aerobic cell counts, but jowl had higher aerobic cell counts than each site before final wash.

• Journal of the Korean GEO-environmental Society
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• v.16 no.1
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• pp.55-60
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• 2015

As the water supply system has been installed over the country, the management of drinking water could be easier and controlled by experts. This helps to supply safe water to public. However, in rural area, small scale water treatment systems or groundwater haves been used as drinking water supplier. The drinking water including groundwater contains various contaminants. Private or small scale water treatment system can be contaminated with heavy metals such as arsenic, selenium and strontium which are usually originated from natural source. Arsenic, selenium and strontium have been determined from the goundwater, small scale water treatment system in the Kyungpook area. The results have been compared with the Korean and international standards. The results were analyzed on the geological characteristics of the area. Among the total of 1,412 samples, 76 samples showed higher concentration of arsenic than WHO guideline and the Korean drinking water standard. Total 4 samples had higher contents of selenium than WHO guideline which was $10{\mu}g/L$. In the analysis of geological characteristics, arsenic was highly released from a few area and which are in order of biotite granodiorite > biotite granite > daegu formation. Selenium has been highly released from biotite granite > black shale > diluvium.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.3
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• pp.98-107
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• 2007

For high-dimensional pattern recognition, such as face classification, the small number of training samples leads to the Small Sample Size problem when the number of pattern samples is smaller than the number of dimensionality. Recently, various LDA-extensions have been developed, including LDA, PCA+LDA, and Direct-LDA, to address the problem. This paper proposes a method of improving the classification efficiency by increasing the number of (sub)-classes through pre-clustering a training set prior to the execution of Direct-LDA. In LDA (or Direct-LDA), since the number of classes of the training set puts a limit to the dimensionality to be reduced, it is increased to the number of sub-classes that is obtained through clustering so that the classification performance of LDA-extensions can be improved. In other words, the eigen space of the training set consists of the range space and the null space, and the dimensionality of the range space increases as the number of classes increases. Therefore, when constructing the transformation matrix, through minimizing the null space, the loss of discriminatve information resulted from this space can be minimized. Experimental results for the artificial data of X-OR samples as well as the bench mark face databases of AT&T and Yale demonstrate that the classification efficiency of the proposed method could be improved.

• Proceedings of the Korean Society of Toxicology Conference
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• 2006.11a
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• pp.65-74
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• 2006

Modem drug discovery requires rapid pharmacokinetic evaluation of chemically diverse compounds for early candidate selection. This demands the development of analytical methods that offer high-throughput of samples. Naturally, liquid chromatography / tandem mass spectrometry (LC-MS/MS) is choice of the analytical method because of its superior sensitivity and selectivity. As a result of the short analysis time(typically 3-5min) by LC-MS/MS, sample preparation has become the rate- determining step in the whole analytical cycle. Consequently tremendous efforts are being made to speed up and automate this step. In a typical automated 96-well SPE(solid-phase extraction) procedure, plasma samples are transferred to the 96-well SPE plate, internal standard and aqueous buffer solutions are added and then vacuum is applied using the robotic liquid handling system. It takes only 20-90 min to process 96 samples by automated SPE and the analyst is physically occupied for only approximately 10 min. Recently, the ultra-high flow rate liquid chromatography (turbulent-flow chromatography)has sparked a huge interest for rapid and direct quantitation of drugs in plasma. There is no sample preparation except for sample aliquotting, internal standard addition and centrifugation. This type of analysis is achieved by using a small diameter column with a large particle size(30-5O ${\mu}$m) and a high flow rate, typically between 3-5 ml/min. Silica-based monolithic HPLC columns contain a novel chromatographic support in which the traditional particulate packing has been replaced with a single, continuous network (monolith) of pcrous silica. The main advantage of such a network is decreased backpressure due to macropores (2 ${\mu}$m) throughout the network. This allows high flow rates, and hence fast analyses that are unattainable with traditional particulate columns. The reduction of particle diameter in HPLC results in increased column efficiency. use of small particles (<2 urn), however, requires p.essu.es beyond the traditional 6,000 psi of conventional pumping devices. Instrumental development in recent years has resulted in pumping devices capable of handling the requirements of columns packed with small particles. The staggered parallel HPLC system consists of four fully independent binary HPLC pumps, a modified auto sampler, and a series of switching and selector valves all controlled by a single computer program. The system improves sample throughput without sacrificing chromatographic separation or data quality. Sample throughput can be increased nearly four-fold without requiring significant changes in current analytical procedures. The process of Bioanalytical Method Validation is required by the FDA to assess and verify the performance of a chronlatographic method prior to its application in sample analysis. The validation should address the selectivity, linearity, accuracy, precision and stability of the method. This presentation will provide all overview of the work required to accomplish a full validation and show how a chromatographic method is suitable for toxirokinetic sample analysis. A liquid chromatography/tandem mass spectrometry (LC-MS/MS) method developed to quantitate drug levels in dog plasma will be used as an example of tile process.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.8 no.2
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• pp.231-241
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• 1998

To assess biological indoor air quality in hospital, concentrations of viable airborne microbes were determined at intensive care unit(ICU), patient room (PR), outpatient waiting room(OPWR) in hospitals of large(1000 beds), middle(500 beds), small(100 beds) hospitals, respectively. Gram positive bacteria, gram negative bacteria, fungi were sampled using suctional sampling method by RCS sampler (Reuter centrifugal air sampler) and RCS GK-A agar plate. In gram positive bacteria groups, CNS(Coagulase Negative Staphylococcus), Micrococcus, Lactobacillus, S. aureus, Enterococcus, St. viridans identified. In gram negative bacteria groups, A. baumannii, Kl. peumoniae and E. coli were identified, and Penicillium was identified in fugi groups. Results of the study were as follows. 1. The highest concentrations of airborne microbes was $971CFU/m^3$ at 5:00 PM in small hospital patient room, and average concentrations of airborne microbes in large, middle and small hospitals were $282CFU/m^3$, $289CFU/m^3$ and $625CFU/m^3$, respectively. Average concentrations of airborne microbes in office(control) was $90CFU/m^3$. Thus, the small hospital showed the worst condition. 2. Representatives of 8 different genera were identified in 150 samples. The most frequently isolated organisms were Staphylococcus (73.0%), Micrococcus (20.7%) and Lactobacillus (4.7%), respectively. Pathogenic microbes isolated were A. baumannii, E. coli, Enterococcus, Kl. peumoniae, S. aureus, St. viridans and Penicillium as fungi. In office, no pathogenic microbes were identified. Average concentrations of airborne pathogenic microbes in large, middle and small hospital were $5CFU/m^3$ (2%), $11CFU/m^3$ (4%) and $12CFU/m^3$ (2%), respectively. Thus, condition in a large hospital was better than those in a middle and a small hospital.

• Journal of Veterinary Science
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• v.25 no.5
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• pp.66.1-66.12
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• 2024

Importance: Porcine epidemic diarrhea virus (PEDV) binds to particular cell surface receptors to penetrate cells. The virus specifically identifies certain carbohydrate structures present on the surface of the cell to facilitate the binding process. Nevertheless, the influence of viral infections on specific alterations of glycoconjugates in the small intestines remains unexplored. Objective: This work aimed to examine the alterations in glycoconjugates in the small intestines of piglets naturally infected with PEDV using lectin histochemistry. Methods: Six piglets including three PEDV-infected and three non-infected piglets were evaluated. Small intestinal samples were histopathologically examined, and lectin histochemistry was performed. Results: Piglets infected with PEDV had significant histological abnormalities in their small intestines, such as pronounced villous atrophy, varying degrees of villous fusion, and diverse mucosal alterations. Specific regions of the duodenum, jejunum, and ileum showed discernible variations in glycoconjugate distribution, as determined by lectin histochemistry. Compared with the controls, the PEDV-infected piglets showed significant changes in N-acetylglucosamine- and galactose-binding lectins (particularly wheat germ agglutinin and Arachis hypogaea (peanut) agglutinin) in multiple intestinal regions. Conclusions and Relevance: These findings can enhance understanding of how viruses such as PEDV impact the glycoconjugate composition of the small intestines and emphasize the potential connection between the pathogenesis of PEDV and glycoconjugate.

• Korean Journal of Materials Research
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• v.22 no.2
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• pp.61-65
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• 2012

A $Li_2O-2SiO_2$ ($LS_2$) glass was investigated as a lithium-ion conducting oxide glass, which is applicable to a fast ionic conductor even at low temperature due to its high mechanical strength and chemical stability. The $Li_2O-2SiO_2$ glass is likely to be broken into small pieces when quenched; thus, it is difficult to fabricate a specifically sized sample. The production of properly sized glass samples is necessary for device applications. In this study, we applied spark plasma sintering (SPS) to fabricate $LS_2$ glass samples which have a particular size as well as high transparency. The sintered samples, $15mm\phi{\times}2mmT$ in size, ($LS_2$-s) were produced by SPS between $480^{\circ}C$ and $500^{\circ}C$ at 45MPa for 3~5mim, after which the thermal and dielectric properties of the $LS_2$-s samples were compared with those of quenched glass ($LS_2$-q) samples. Thermal behavior, crystalline structure, and electrical conductivity of both samples were analyzed by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and an impedance/gain-phase analyzer, respectively. The results showed that the $LS_2$-s had an amorphous structure, like the $LS_2$-q sample, and that both samples took on the lithium disilicate structure after the heat treatment at $800^{\circ}C$. We observed similar dielectric peaks in both of the samples between room temperature and $700^{\circ}C$. The DC activation energies of the $LS_2$-q and $LS_2$-s samples were $0.48{\pm}0.05eV$ and $0.66{\pm}0.04eV$, while the AC activation energies were $0.48{\pm}0.05eV$ and $0.68{\pm}0.04eV$, respectively.