• Tribology and Lubricants
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• v.11 no.4
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• pp.35-44
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• 1995

Within the practical ranges of speed and load, the formation of transfer films and the consequent effects on the friction and wear behavior of ceramic materials during repeated pass sliding contact were studied. These tests were done using $Al_{2}O_{3}$, SiC and $Si_{3}N_{4}$ with the cylinder-on-flat test configuration. The three pairings behaved differently, even if some wear mechanisms were common to the three systems. The $Al_{2}O_{3}$ pair showed the least wear in overall conditions, followed by the $Si_{3}N_{4}$ pair in harder sliding conditions. The wear of SiC was very high at severe loading. In case of $AL_{2}O_{3}$ and $Si_{3}N_{4}$, the transfer film, whenever formed, is strongly attached, enough to resist being wiped off by the slider. As a consequence, the formation of this f'fim leads to a decrease in the wear rate because of the protecting role of the film. The presence of the film at the contact interface also results in high friction. Also, the wear rate of each ceramics is related to the frictional power provided by load, speed and friction.

• Transactions of Materials Processing
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• v.21 no.1
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• pp.30-35
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• 2012

FIM(Film Insert Molding) is an innovative method of producing decorated parts for a wide range of products. Because it requires fewer steps when compared to conventional production methods, the time and cost of manufacturing high quality components can be reduced considerably. In this paper, the effects of processing conditions on the warpage of film-insert molded plate were investigated by using a design of experiments. The dominant factors affecting warpage were mold temperature and holding pressure. Warpage increased with the temperature difference between stationary mold and fixed one. Even when the mold temperature difference was zero, the plate with a film was bent after ejection such that the film side protruded. As holding pressure increased, warpage decreased significantly. In addition warpage increased with time increment for the film-insert molded plates.

• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1345-1349
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• 2001

New quadruply-bridged calix[6]arenes (I-V) have been studied as cesium selective ionophores in poly(vinyl chloride) (PVC) membrane electrodes. PVC membranes were prepared with dioctyl sebacate (DOS) or 2-nitrophenyl octyl ether (o-NPOE) as the sol vent mediator and potassium tetrakis(p-chlorophenyl)borate as the lipophilic salt additive. These ionophores produced electrodes with near-Nernstian slope. The selectivity coefficients for cesium ion with respect to alkali, alkaline earth and ammonium ions have been determined. The lowest detection limit (logaCs+ = -6.3) and the higher selectivity coefficient (logkpotCs+,Rb+ = -2.1 by SSM, -2.3 by FIM for calix[6]arene I) for Cs+ have been obtained for membranes containing quadruply-bridged calix[6]arenes (I, Ⅱ, Ⅲ), which have no para t-butyl substituents on the bridging benzene ring.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.14 no.23
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• pp.71-100
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• 1991

Investment in FA facilities has been accerelated since 1986, turning point by labor strife in Korea firms. Most commonly adopted automation tech, in their manufacturing process consists of NC. Robotics, PLC, CAD/CAM now on and further confused system oriented FMS, CIM, etcs. undergoing. But for all their remarkable notices in manufacturing systems, The competitive position on product cost, quality, shorten delivery and profit has never been recovered in global swing market. To make some empirical suggestions with a view to competitive strategy of Korea firms by FA, to the conclusion largely FA tech. adoption can be justified only when its application on new product productions and improved the structure of products comparatively. Because of when it was applied in old production process. The effectiveness is very doubtful to the lacks of consistent and integrate manufacturing policy with the strategy of the fim and their poor standardization level in shop floors.

• Korean Journal of Veterinary Research
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• v.63 no.2
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• pp.16.1-16.6
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• 2023

Salmonella spp. are pathogens involved in most salmonellosis in rabbits. This study examined Salmonella disease in rabbits raised in Thua Thien Hue, Vietnam. Two hundred and 56 rectal swabs of rabbits were taken, and a carrier rate of 33.98% was found. In addition, all the isolated Salmonella spp. strains were 100% motile; positive for H₂S, catalase, Voges Proskauer, coagulase, citrate, maltose, and dextrose; and negative for indole, methyl red, urease, oxidase, sucrose, and lactose. The Kirby-Bauer method showed that these Salmonella strains were susceptible to doxycycline (93.2%), tetracycline (84.1%), and levofloxacin (65.9%). On the other hand, they were highly resistant to streptomycin (95.5%), ampicillin (93.2%), colistin (40.9%), and gentamicin (34.1%). Furthermore, polymerase chain reaction used to screen for virulence and specific genes of Salmonella strains showed that all Salmonella strains isolated carried InvA, fimA, and Stn.

• Iberoamérica
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• v.13 no.1
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• pp.1-39
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• 2011

O presente estudo tem como objetivo principal analisar a influência de vocabulários de origem africana em uso no português brasileiro(PB). A fim disso, observamos os tipos e as características das línguas africanas. E ainda, para compreender a situação atual de uso desses termos no Brasil, apresentamos um panorama do registro dos vocábulos de origem africana no PB, e organizamos os vocabulários em três categorias, especialmente, nos registros dos séculos XIX e XX. Em primeiro, a categoria 1 pode ser usada em qualquer interação social, contrastando com as outras duas categorias. Em segundo, a categoria 2 é constuída de termos informais, de uso coloquial que, eventualmente, dependendo da situação, são substituídos por outras. Por último, a categoria 3 é de termos marcadamente informais, de uso restrito. Através disso, comparamos os registros anteriores com os dados obtidos da nossa pesquisa. Com os resultados, podemos reconhecer a estabilidade e o dinamismo do uso desses termos hoje no PB.

• Kyungpook Mathematical Journal
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• v.64 no.2
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• pp.353-369
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• 2024

In this study, we investigate the unknown time-dependent heat source function in inverse problems. We consider three general nonlocal conditions; two classical boundary conditions and one nonlocal over-determination, condition, these genereate six different cases. The finite integration method (FIM), based on numerical integration, has been adapted to solve PDEs, and we use it to discretize the spatial domain; we use backward differences for the time variable. Since the inverse problem is ill-posed with instability, we apply regularization to reduce the instability. We use the first-order Tikhonov's regularization together with the minimization process to solve the inverse source problem. Test examples in all six cases are presented in order to illustrate the accuracy and stability of the numerical solutions.

• Journal of Life Science
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• v.31 no.3
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• pp.330-337
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• 2021

This study was conducted to investigate the potential of Stewartia koreana as oral healthcare materials. The antibacterial activity of ethanol extracts from leaves and branches of S. koreana against oral bacteria was confirmed. The leaf and branch extracts (1 mg/disc) showed antibacterial activity against P. gingivalis only among several tested oral bacteria. The leaf extracts showed higher antibacterial activity, with values similar to those of chlorhexidine, which was used as a positive control. The MIC of the leaf extract against P. gingivalis was 0.4 mg/ml and showed bacteriostatic action. The inhibitory effects of the extract on biofilm formation and on gene expression related to biofilm formation by P. gingivalis were determined by biofilm biomass staining, scanning electron microscopy (SEM), and qRT-PCR analysis. The biofilm production rate and cell growth of P. gingivalis in the cultures treated with 0.2-2.0 mg/ml of S. koreana leaf extracts were significantly decreased in a concentration-dependent manner. The inhibitory effect on the formation of P. gingivalis biofilms at concentrations of 1 mg/ml was confirmed by SEM. The qRT-PCR analysis showed concentration-dependent suppression of the fimA and fimB gene expression associated with fimbriae formation in the cultures treated with 0.2-2.0 mg/ml S. koreana leaf extract. These results support the conclusion that S. koreana leaf extracts can be used as oral healthcare materials derived from natural materials, as demonstrated by the antibacterial action and inhibition of biofilm formation of P. gingivalis.

• The Journal of Korean society of community based occupational therapy
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• v.1 no.2
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• pp.11-20
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• 2011

Objective : The purpose of this study was to investigate the effects of the activities of daily living on time-use of the Elderly in facility. This study is also to provide basic data of the redesign time management and lifestyle as occupational therapy. Methods : The subjects were 20 elderly people (over 65 years) who live in S institution of Daejeun from August 11th, to August 22th in 2008. We used time table, interview and FIM which was to evaluate the ability to collect the general characteristics of these subjects(gender, age, moving period, education). Results : There was no significant different between the general characteristics of the subjects and activity of daily living. The more they spent time in Active BADL and IADL, the more they got higher scores in ADL performance ability(p<0.01). The more they spent time in the more they got higher score in ADL performance ability(p<0.05). Conclusion : We could know the amount of spending time of the elderly in Daejeun area facility and it related to activity of daily living. To improve the efficiency of time-use of the elderly, it is needed the role of occupational therapists. They should prepare a intervention to maintain active and positive life of the elderly.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5229-5237
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• 2012

Occupational therapist is required for patient-centered approaches to actively seek the perspectives of patients and their families in clinical settings. The purpose of this study was to investigate the current trends and to suggest future-oriented view of examination and assessment used by neurological occupational therapist in clinical settings. Sixty-six occupational therapists who work in persons with neurological disorders participated in this study. The survey was measured from Seoul and GyeongGi by means of E-mail about commonly used assessment tools and selecting considerations. The participants were 66 neurological occupational therapists. The number of patients by one day was from 10 to 14 persons, and the length of time for initial evaluation was 20-40 minutes per one patient, and reexamination periods was every 1 month or as functional changes were detected. The using tool was not limited only neurological tools, and choice consideration was the reliability and validity of clinical measures. The most frequently used tools for adults were: JHFT for motor function in upper extremity, MMSE-K for cognitive perceptual assessment, MBI for daily activity assessment, and COPM for occupational performance. The most frequently used tools for child were: MVPT for cognitive perceptual assessment and Wee-FIM for daily activity assessment. The results of this study suggest that it is necessary to integrate and associate patient-report, care-giver report, and results of performance-based assessment for estimating plan of care more quality.