• Korea-Australia Rheology Journal
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• v.14 no.1
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• pp.11-16
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• 2002

Cephalosporium acremonium is a filamentous microorganism producing cephalosporin C. The morphological differentiation of C. acremonium in submerged culture is closely related with the rheological properties of culture broth and production of cephalosporin C. In this study, the rheological and morphological properties of culture broth of C. acremonium were investigated. In the seed broths of shake-flask and fermenter culture, the Herschel-Berkley equation was in excellent agreement with experimental results in the whole range of shear rate. In the seed broths of shake-flask culture, morphological differentiation into arthrospores affected to changes of apparent viscosity. But results in the fermenter culture, morphological factors such as mean hyphal thickness and the number of tips gave more effect on changes of apparent vitacosity than differentiation into arthrospores. Overall, it suggested that the morphological parameters measured by image analysis can be used as a good parameter to indicate the rheological properties of culture broth of C. acremonium M25.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.06a
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• pp.101-108
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• 1999

This paper was undertaken to do morphological analysis of wear particles for sliding members hydrauric rotary acuator. The lubricating wear test was performed under different experimental conditions using the wear test device and wear specimens of the pin on disk type was rubbed in paraffinic base oil by three kinds of lubricating materials, varying applied load, sliding distance. The four shape parameters (50% volumetric diameter, aspect, roundness and reflectivity) are used for morphological analysis of wear particles. The results showed that the four shape parameters of wear particles depend on a kind of the lubricating materials. It was capable of presuming wear volume for three kinds of materials on driving time.

• Tribology and Lubricants
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• v.14 no.4
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• pp.79-87
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• 1998

Morphological analysis of wear particles in the lubricating oil is a very effective and versatile means of lubricant analysis for machine condition monitoring and fault diagnosis. The prospects for determining quantitative information about wear particle morphology have been considerably enhanced by recent developments reported in the application of image processing and analysis techniques. This study was undertaken to investigate the influence of oiliness agent and extreme pressure agent on the shape of wear particles. The wear test was performed under different experimental conditions with stearic acid, dibenzyl disulfide(DBDS) and tricresol phosphate(TCP) in paraffinic base oil. Wear particles characteristics were described using four shape parameters, namely 50% volumetric diameter, aspect, roundness and reflectivity. The results showed that the four shape parameters of wear particles depend on a kind of the additives. This analysis of wear debris with computer image processing techniques is sufficient to distinguish some types of wear debris. The wear volume of three kinds of the specimens are affected by the additives with boundary films.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.1
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• pp.79-87
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• 1999

The most part of the faculty drop a trouble and damage of machine equipment even if whatever cause they break out take place at local and trifling place and the factor dominating their trouble is due to wear debris occurred in the lubricated machine moving surface. This study has been car-ried out to identify morphology of wear debris on the lubricated machine moving system by means of computer image analysis. Namely the wear debris contained in lubricating oil extracted from movable machine equipment will be filtered through membrane filter(void diameter 0.45${\mu}m$) and will be analyzed with its data information such as 50% volume diameter aspect roundness and reflectivity. Morphological characteristic of wear debris is easily distinguished by four shape parameters it is necessary to divide small class of every 100 wear debris in total wear particles in order to distinguish morphological characteristic of wear debris more easily by computer image analysis. We are sure that operation condition diagnosis of the lubricated machine moving surfaces is possible by computer image analysis.

• The Korean Journal of Pain
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• v.34 no.3
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• pp.369-370
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• 2021

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.971-976
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• 2005

In a 30-1 bioreactor culture, whole differentiation occurred from 48 h, and then proceeded rapidly. As swollen hyphal fragments and arthrospores increased, cephalosporin C (CPC) production increased exponentially to $1.85\;g/1^{-1}$ at 72 h. To explain the morphological changes of Cephalosporium acremonium M25 more quantitatively, specific differentiation rates and fractal analysis were employed. Specific differentiation rates of morphological factors varied greatly during the period of culture time from 48 h to 72 h, when CPC production increased significantly. Changes of fractal dimensions showed a pattern similar to that of the specific rate of arthrospores. Furthermore, it was inversely related to the specific rate of tips. Overall, it was suggested that the fractal dimension had potential for a new morphological parameter of fungal morphology, showing complex differentiation patterns.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.4
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• pp.53-61
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• 1989

A morphological analysis is described to extract the informations which are required in syntactic and semantic analysis of the Korean language. The noun and particle are separated in a noun phrase, the selecting conditions are specified to analyze the compound noun and a restoring rule is represented to process the irregular compound noun. The stem and ending are separated in normal verbals and a logical representive form is proposed to the anomalously inflected word and contracted vowels. The logical representation is composed of the attribute value an analyzing rule. The redundancy of noun is reduced in the dictionary as the verb of a "Nounformed HA-" is processed by "noun" and "HA-", separately and a predicative "IDA" is analyzed by Q parameter. The processing form of negation is also derived and the morpheme and basic structure of compound predicative parts are presented.

• Journal of Biomedical Engineering Research
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• v.22 no.3
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• pp.269-273
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• 2001

Proper determination of pacing threshold is important for patient safety and pacemaker longevity. In general, cardiac muscle contractions caused by pacing pulses are verified by observing the morphology of surface ECG displayed on a monitor. In this study, a method of automatic pacing threshold determination based on morphological difference between intrinsic and paced ECGs was developed. First, characteristics of intrinsic ECG and paced ECG were analyzed in time and frequency domain and a proper discrimination parameter was extracted. Then, the automatic capture verification method based on the parameter was developed and applied to 23 pacemaker patients. The selected parameter was the area of ventricular depolarization wave during 80ms after pacing stimulus. It was found that the method was reliable and effective in identifying paced ECG and, thereby, determing a proper pacing threshold.

• The Korean Journal of Pain
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• v.34 no.2
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• pp.229-233
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• 2021

Background: Iliotibial band friction syndrome (ITBFS) is a common disorder of the lateral knee. Previous research has reported that the iliotibial band (ITB) thickness (ITBT) is correlated with ITBFS, and ITBT has been considered to be a key morphologic parameter of ITBFS. However, the thickness is different from inflammatory hypertrophy. Thus, we made the ITB cross-sectional area (ITBCSA) a new morphological parameter to assess ITBFS. Methods: Forty-three patients with ITBFS group and from 43 normal group who underwent T1W magnetic resonance imaging were enrolled. The ITBCSA was measured as the cross-sectional area of the ITB that was most hypertrophied in the magnetic resonance axial images. The ITBT was measured as the thickest site of ITB. Results: The mean ITBCSA was 25.24 ± 6.59 ㎟ in the normal group and 38.75 ± 9.11 ㎟ in the ITBFS group. The mean ITBT was 1.94 ± 0.41 mm in the normal group and 2.62 ± 0.46 mm in the ITBFS group. Patients in ITBFS group had significantly higher ITBCSA (P < 0.001) and ITBT (P < 0.001) than the normal group. A receiver operator characteristic curve analysis demonstrated that the best cut-off value of the ITBT was 2.29 mm, with 76.7% sensitivity, 79.1% specificity, and area under the curve (AUC) 0.88. The optimal cut-off score of the ITBCSA was 30.66 ㎟, with 79.1% sensitivity, 79.1% specificity, and AUC 0.87. Conclusions: ITBCSA is a new and sensitive morphological parameter for diagnosing ITBFS, and may even be more accurate than ITBT.

• Korea-Australia Rheology Journal
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• v.16 no.3
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• pp.135-140
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• 2004

Morphological and rheological properties of the poly(methyl methacrylate) (PMMA) and polystyrene (PS) blends were studied by scanning electron microscopy (SEM) and advanced rheometric expansion system (ARES). From the SEM results, the PMMA-PS blends showed dispersed morphology and the particle size of the dispersed phase was quite small (0.1~0.6 $\mu\textrm{m}$ compared with other immiscible polymer blends. Values of the interfacial tension of the PMMA-PS blend were obtained from the Choi-Schowalter and the Palierne emulsion models using the storage modulus of the PMMA and PS, and found to be 1.0 and 2.0 mN/m, respectively. The interfacial tension between the PMMA and PS was also calculated from the Flory-Huggins polymer-polymer interaction parameter ($\chi$) and found to be from 0.98 to 1.86 mN/m depending on the molecular weight and composition. Comparing the values of the interfacial tension from the Flory-Huggins polymer-polymer interaction parameter and the values measured by oscillatory rheometer, it is suggested that the interfacial tension of the PMMA-PS blend obtained from the polymer-polymer interaction parameter are in good agreement with the values obtained by rheological measurements.