• Journal of Magnetics
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• v.16 no.2
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• pp.97-100
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• 2011

Bilayers of soft NiFe (150 nm-420 nm) on hard Ni (150 nm) were prepared by electrodeposition. The process of magnetization reversal in the NiFe/Ni bilayers was then investigated. The hysteresis loop generated by a magnetization reversal of soft NiFe under a positive saturation state of a hard Ni layer shows a shift along the negative field axis, which is clear evidence for the exchange spring effect in the NiFe/Ni bilayers. The dependence of the coercive field $H_c$ and exchange bias field Hex on the thickness of the NiFe layer was also investigated. As the NiFe thickness increases from 150 nm to 420 nm, both $H_c$ and $H_{ex}$ decrease rapidly from $H_c$= 51.7 Oe and $H_{ex}$ = 12.2 Oe, and saturate to $H_c$ = 5.8 Oe and $H_{ex}$ = 3.5 Oe.

• Journal of Korea Foundry Society
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• v.26 no.2
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• pp.85-91
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• 2006

Inclusions in Ti investment castings are generally known to have detrimental effects on the performance of the castings. However, actual inclusions are infrequent and hard to be located. As a result, it is extremely difficult to obtain sufficient amount of fatigue test specimens of titanium investment castings having inclusions in the gage section. Thus, in-depth research of the adverse influence of inclusions is also hindered. To address this problem, a new casting methodology of specimens containing hard alpha inclusions was developed in this study. To guarantee successful introduction of an inclusion and casting, a carefully designed mold with 8 legs and a special tool were employed. After solidification, castings were cut, and X-ray radiography determined that the inclusions were successfully incorporated into the castings. The castings were further prepared to obtain multiple test specimens and they were fatigue-tested consecutively. Fractography analysis confirmed that fatigue cracks initiated at the hard alpha inclusion. In a nonlinear regression model, the fatigue life can be modeled as an exponential function with a negative exponent of the cross-sectional area of an inclusion. The fatigue life of Ti specimens containing inclusions is inversely proportional to the cross-sectional area of an inclusion.

• Applied Chemistry for Engineering
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• v.7 no.4
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• pp.809-812
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• 1996

Generalized van der Waals equation of state combined with the core-softening theory and temperature dependent repulsive and attractive terms exhibit the anomalous thermal expansion, i.e. density anomaly. Density maxima occur at both positive and negative pressure when the hard-core diameter decreases with increasing temperature, $db_r/dT_r<0$, and at negative pressure when the repulsive force increases with increasing temperature, $da_r/dT_r>0$.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.1
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• pp.1-11
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• 2014

The purpose of this study was to find out the taste adjectives of Korean cooked rice, noodles, porridges and rice cakes as well as to analyze the relation between the taste adjectives of foods. We gathered and chose 36 related Korean adjectives for expressing not only the taste but also the smell of foods. Subsequently, we performed a sensory evaluation for 18 Korean foods with 20 trained panelists in order to check the proper adjectives when they tasted the foods. The often selected taste adjectives were 'sweet', 'tasty', 'sticky' and 'soft' among 36 taste adjectives. The PCA was performed to summarize the taste adjectives for each of the 18 foods. The principal components explained 50.94 % of the total variance. The adjectives 'spicy' and 'refresh' were closely related to one another in the positive direction of PC1. In contrast, 'weak', 'hard' and 'sticky' were closely related to one another in the negative direction of PC1. PC2 was marked by 'hard' and 'spicy', which were located in the positive direction. In contrast, 'weak' and 'soft' were located in the negative direction. PC3 was marked by 'nutness', 'bitter' and 'spicy', which are associated with bibimbab, conveying a high degree of correlation among them in a positive direction. In contrast, 'cool', 'sour' and 'refresh' were located in the negative direction.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.42 no.6
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• pp.383-387
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• 2016

Oral verruciform xanthoma (OVX) is an uncommon lesion that appears on the oral mucosa. The aim of this paper was to discuss the probable etiopathogenesis of OVX in the hard palate, reinforcing the importance of including this lesion in the differential diagnosis of verrucous lesions. A 43-year-old male smoker presented with a painless lesion with a verrucous surface and erythematous spots on the hard palate. Excisional biopsy revealed oral mucosa consisting of hyperkeratosis, acanthosis, and elongated rete pegs. Subjacent connective tissue showed numerous foam cells with clear cytoplasm and pyknotic nucleus, negative on periodic acid-Schiff staining. Immunohistochemical analysis revealed foam cells positive for anti-CD68 antibody, while anti-KI-67 antibody was restricted to the basal layer of the oral epithelium. A final diagnosis of OVX was established. The patient showed no signs of recurrence after seven months of follow-up. Physical trauma and smoking habits can be directly related to the etiology of verruciform xanthoma because the lesion is chronic and inflammatory with slow growth, and sites if high trauma are more often affected by such a lesion. The hard palate is the second most commonly affected site, and local trauma caused by smoking can be a cause of this type of lesion.

• KSTLE International Journal
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• v.5 no.1
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• pp.23-27
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• 2004

The object of the present work is the numerical analysis of the computer hard disk slider. The pressure between slider and disk surfaces is calculated using the Boundary Fitted Coordinate System and Divergence Formulation for the nonlinear Reynolds' equation solution. The optimization scheme is applied to search for the steady state position of the slider. The simplified method is given for the case of the fixed inclined pad. The film thickness ratios and pitching and rolling angles are considered as alternative choice of the slider's coordinates. The behavior of the objective function for the Negative Pressure slider is studied in details. Methods of conjugate directions and feasible directions are applied.

• Tribology and Lubricants
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• v.16 no.5
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• pp.395-402
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• 2000

The effect of particulate contamination on friction and wear between a negative-pressure picoslider and a laser-textured disk was studied. Particles of different concentrations, materials and sizes were injected to the head-disk interface (HDI), consisting of disks with various textures, at the same speed. In a contaminated environment, durability of head-disk interface gradually decreased as the particle concentration increased. Large particles caused HDI failure early and resulted in an extensive damage to the slider and disk surfaces. Hard particles also caused HDI failure earlier and damages more extensive than soft ones. Based on the test results, mechanisms of HDI failure with picoslider were presented.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.7
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• pp.579-589
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• 2021

In the era of tough competition, the customer's emotional attachment to brand plays a vital role to the successes and failures of enterprises. Specifically in the case of doing business online, brands have to cope with the troubles of rising from brand hate as brand avoidance, negative word of mouth and brand retaliation. Traditionally, the brand communication is very hard to control and with online communities, the problems tend to be even more severe. This paper aims to explore and discuss the core concept, the driven factors and the actionable consequences of brand hate among netizens. A total of 358 valid responses were obtained from surveys taken from the internet users across the nation. Partial Least Square - Structural Equation Modeling (PLS-SEM) was conducted using Smart PLS to assess the hypotheses. The result shows that the expression of brand hate among netizen consists of active hate and passive hate. Deficit value, deceptive advertising, negative past experience and ideology incompatibility have been confirmed as influencing factors on customers' brand hate emotion. Then brand hate itself causes the customer's actionable outcomes such as brand avoidance, brand negative word of mouth and brand retaliation. Along with the theoretical contributions and managerial implications have been recommended for enterprises to avoid netizens' brand hate.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.464-467
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• 1997

In this paper, a high precision track following control algorithm is proposed for micro electrostatic actuator considering of the application for hard disk drive. The micro electrostatic actuator proposed has nonlinear voltage-displacement characteristic in a working range of 0.8.mu.m and has uni-directional movement. Mid range reference and open-loop bias are proposed for the revision of negative position error, and inverse model for linearization.

• Proceedings of the KSR Conference
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• 2002.05a
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• pp.142-146
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• 2002

The purpose of this article is to depict the organizational effectiveness of "A" Subway Corporation based on the cognitive response of employees(subway drivers). To attain this purpose, several aspects of current personnel aid organization management system and organizational culture are surveyed through questionaire and analyzed by SPSS. The questionaire includes two parts of items. First, it includes items on personnel-related factors such as evaluation system job, wage, role, leadership and job satisfaction. Second, it includes items on organizational culture model suggested by Rousseau. The major findings are : 1) In general the cognitive response of driven concerning personnel-related aspects is to a certain degree negative. 2) The cognitive response of drivers concerning culture-related aspects is awfully negative. 3) Job satisfaction of drivers is highly related to role and leadership factors in terms of personnel-related aspects, on the one hard, and to achievement factor in terms of culture, on the other hand.