• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.11a
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• pp.341-346
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• 2000

The effect of OTS(octadecyltrichlorosilane) SAM(self-assembled monolayer) on the micro-adhesion has been studied. OTS SAM was formed on the Si(100) surface and SPM (scanning probe microscope) tips with different radius of curvature were fabricated by a series of masking and etching processes. Pull-off forces of different tips on Si and OTS SAM surfaces were measured by SPM in different relative humidities. The surface of OTS SAM was changed to hydrophobic surface and the micro-adhesion force of OTS SAM was lower than that of pure Si. As the tip radius of curvature and the relative humidity increased. the micro-adhesion force increased. Based on the test results. the main parameter affected to the micro-adhesion was absorbed humidity on the surface.

• Journal of Ceramic Processing Research
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• v.19 no.6
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• pp.525-529
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• 2018

The antireflective (AR) coated poly methyl methacrylate (PMMA) substrate was deposited by atomic layer deposition (ALD) on a self-assembled monolayer (SAM) to improve hydrophobicity and mechano-chemical properties of organic thin films. The water contact angles (WCA) were tested to characterize the surface wettability of SAM octadecyltrichlorosilane (OTS) films. Results showed that a contact angle of $105.9^{\circ}$ was obtained for the SAM films with an annealing process, and the highest WCA of $120^{\circ}$ was achieved for the films prepared by the SAM and ALD multi-process. The surface morphology of the SAM films with different assembly times and varying number of ALD cycles was obtained by atomic force microscopy (AFM). The maximum light transmittance for the SAM films on the PMMA substrate reached 99.9% at a wavelength of 450 nm. It was found that the SAM surfaces were not affected at all by the ALD process.

• Biomolecules & Therapeutics
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• v.5 no.1
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• pp.23-35
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• 1997

Physiological effects in SAM P6 and Rl by administration of Cervus cornu, Astragali Radix, Rehmanniae Radix, and Angelicae Radix extracts were screened to know in vivo activities of each extracts. We measured complete blood cells (CBC) such as aBC, HGB, and HCT using coulter's method. Plasma concentrations of albumin, glucose, alkaline phosphatase, calcium, creatinine, inorganic phosphate, urea and total iron ere also analyzed using biochemical clinical autoanalyzer. Plasma concentrations of cortisol, total T$_3$, and total T$_4$ were measured by chemiluminescent immunoassay methods. At 12 weeks after birth, Cervus conu or Astragali Radix or Rehmanniae Radix extracts were given 5 g/Kg.day p.o. for 0,7,14,21, and 30 days each in both SAM Rl and SAM P6. Angelicae Radix study was done the same as the others except the mice were 16 weeks after birth. The RBC, HGB, and HCT levels after administration of Astragali and Rehmanniae were elevated in SAM Rl, but those in Cervi study were increased in SAM P6 the most. Decreases in alkaline phosphatase concentration of SAM Rl and P6 after Cervi administration were detected. Total plasma iron concentration was decreased by Angelicae administration in SAM P6. In general, Angelicae and Rehmanniae stimulate increases in cortisol, but total T$_3$ and T$_4$ levels were also elevated by all these extracts. In conclusion, these herval medicine extracts help hematopoiesis in SAMs through probably different mechanisms.

• Tribology and Lubricants
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• v.18 no.4
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• pp.267-272
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• 2002

Nano adhesion between SPM(scanning probe microscope) tips and DDPO$_4$(octadecylphosphoric acid ester.) and ODPO$_4$(octadecylphosphoric acid ester) SAM(self-assembled monolayer.) was experimentally studied. Tests were performed to measure the nano adhesion and friction in both AFM(atomic force microscope) and LFM(lateral force microscope) modes with the applied normal load. DDPO$_4$ and ODPO$_4$ SAM were formed on Ti and TiOx surfaces. Ti and TiOx were coated on the Si wafer by ion sputtering. Adhesion and friction of DDPO$_4$ and ODPO$_4$ SAM surfaces were compared with those of OTS(octadecyltrichlorosilane) SAM and DLC surfaces. DDPO$_4$ and ODPO$_4$ SAM converted the Ti and TiOx surfaces to be hydrophobic. When the surface was hydrophobic, the adhesion and friction forces were found lower than those of bare surfaces. Work of adhesion was also discussed to explain how the surface was converted into hydrophobic Results also showed that tribological characteristics of DDPO$_4$ and ODPO$_4$ SAM had good properties in the adhesion, friction, wetting angle and work of adhesion. DDPO$_4$ and ODPO$_4$ SAM could be one of the candidates for the bio-MEMS elements.

• Journal of Society of Preventive Korean Medicine
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• v.11 no.1
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• pp.55-64
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• 2007

This study was carried out to examine that the SamJae Theory(三才思想) was applied for a philosophic background of medical ethics. SamJae theory is not the system of three categories, which is unlike to the meaning of the word 'Sam(三)', but it is the system of two categories with 天(陽) and 地(陰) which are dividing all creations and phenomenons in the universe into two. Nevertheless, the reason why we divide all the universal creations and phenomenons into three, 天, 地 and 人, and also why we give a name 'SamJae' to this theory using the word 'Sam' meaning three, is to emphasize the human free volition that comes from the independent human life in the universe composed of 天(陽) and 地(陰). In other word, the core concept of SamJae theory is not 天(陽) and 地(陰) but 人 which symbolize the independent free volition of human. Therefore, if we try to use SamJae theory as a philosophic background of medical ethics, we can establish a comprehensive theoretical system including the existing ethical theories such as utilitarianism.

• Tribology and Lubricants
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• v.20 no.2
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• pp.51-57
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• 2004

Micro/nano adhesion and friction properties of mixed self-assembled monolayer (SAM) with different chain length for MEMS application were experimentally studied. Many kinds of SAM having different spacer chains(C6, C10 and C18) and their mixtures (1:1) were deposited onto Si-wafer, where the deposited SAM resulted in the hydrophobic nature. The adhesion and friction properties between tip and SAM surfaces under nano scale applied load were measured using an atomic force microscope (AFM) and under micro scale applied load were measured using ball-on-flat type micro-tribotester. Surface roughness and water contact angles were measured with SPM (scanning probe microscope) and contact anglemeter. Results showed that water contact angles of mixed SAMs were similar to those of pure SAMs. The morphology of coating surface was roughened as mixing of SAM. Nano adhesion and nano friction decreased as increasing of the spacer chain length and mixing of SAM. Micro friction was decreased as increasing of the spacer chain length, but micro friction of mixed SAM showed the value between pure SAMs. Nano adhesion and friction mechanism of mixed SAM was proposed in a view of stiffness of spacer chain modified chemically and topographically.

• Toxicological Research
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• v.11 no.2
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• pp.261-266
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• 1995

Age-related change in the frequency of spontaneous sister chromatid exchange (SCE) and chromosornal aberrations were investigated in bone marrow cells of accelerated senescence-resistant mice (SAM R1) and senescence accelerated ones (SAM P1). And the effect of chronic treatment of ginseng extract (Panax ginseng C.A. Meyer) on these chromosomal abnormalities was tested in SAM P1. SCE frequency in the cells was progressively increased with age in both mice, but it was consistently higher in SAM P1 than in SAM R1 at all corresponding age. Chromosomal aberrations were, however, not significantly changed with age except that it was slightly increased in only aged SAM P1. Interestingly, the rate of these genetic instabilities in SAM P1 was remarkably retarded by long-term administration of ginseng water extract (0.05% in drinking water). These results suggest that frequency of spontaneous SCE in bone marrow cells increase in parallel with senescence of the mice, and SAM P1 is in the condition of being more exposed than SAM R1 to DNA damaging factors. These also indicate that long-term treatment of ginseng may reduce the genetic damage.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.517-524
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• 2018

This purpose of this research is to observe the influence of non-condensable gas (NCG) on a horizontal super-hydrophobic aluminum tube and compare it with a bare aluminum tube. To achieve super-hydrophobic characteristics, an aluminum tube was coated with a Self-Assembled Monolayer (SAM). The overall heat transfer coefficient U was used to represent the condensation performance. The NCG mass fraction was the main variable, and its range was 0.08 to 0.45. The condensation performance of the SAM tube and bare tube increased with decreasing mass fraction of NCG. The SAM tube showed 1.9 to 2.5 times larger dropwise condensation performance than the bare tube. When the mass fraction of NCG decreased in the SAM tube, the rate of increase of the SAM tube was lower because flooded condensation occurred. In addition, filmwise condensation occurred in the SAM tube when more active condensation was generated, and its performance was lower than that of the bare aluminum tube. The flooded and filmwise condensation in the SAM tube is explained by the pinning effect. In conclusion, controlling the condition of the condenser is necessary to improve the condensation performance by surface modification a SAM.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.512-515
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• 2002

The lubrication characteristics of SAM(self-assembled monolayer) have been investigated according to the change of surface group and surface temperature treatment with FDTS(1H, 1H, 2H, 2H-Perflurodecyltrichlorosilane) SAM and OTS(octadecyltrichlorosilane) SAM in micro scale. From the experimental results, it was found that OTS SAM gets destroyed at $200^{\circ}C$ and stiction and fiction coefficient increased, but FDTS SAM was stable up to $400^{\circ}C$. Also, it was found that the friction coefficient of normal OTS SAM is lower than that of FDTS SAM, but stiction is vice versa. This work shows the importance of surface group of self-assembled monolayer to control the lubrication characteristics and thermal stability.

• Journal of the Korean Operations Research and Management Science Society
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• v.34 no.4
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• pp.43-56
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• 2009

In korean peninsular, aircraft defense with SAM (Surface-to-Air Missile) is very important because of short range of combat space in depth. Effective and successful defense operation largely depends on two factors, SAM's location and the number of SAM for each target based on missile's availability in each SAM's location. However, most previous papers have handled only the former. In this paper, we developed Set covering model which can handle both factors simultaneously and Multi-heuristic algorithm for solving allocation problem of the batteries and missile assignment problem in each battery. Genetic algorithm is used to decide optimal location of the batteries. To determine the number of SAM, a heuristic algorithm is applied for solving missile assignment problem. If the proposed model is applied to allocation of SAM, it will improve the effectiveness of air defense operations.