• Journal of Korean Ophthalmic Optics Society
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• v.16 no.4
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• pp.403-408
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• 2011

Purpose: To study the concentration distribution and diffusion depth in tinted lenses using the law of diffusion. Methods: The measured values taken from experiments were fitted with the theoretical fitting curve induced on the basis of Fick's second law of diffusion. Results: The fitting curves were in very good agreement with the measured values. As the results, we found the quantitative relationship between mass of dye solution diffused into the tinted lens per unit area and dyeing time, and evaluated concentration distribution of dye in tinted lens, diffusion depth, etc. Conclusions: The dyeing mechanism of tinted lenses can be well described by diffusion theory.

• Knowledge Management Research
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• v.9 no.3
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• pp.77-105
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• 2008

This study primarily aims at identifying what factors significantly affect the diffusion of knowledge management systems(KMS) and finding out how these identified factors can be effectively managed, especially for Korean companies. The research model is derived based on previous researches on innovation diffusion, information systems implementation, and KMS. The model is used to examine the role of determinants in influencing the extent to which KMS is diffused within organizations. Independent variables of this research are composed of technical characteristics, organizational characteristics and environmental characteristics. 'Breadth of diffusion' and 'depth of diffusion' concept are used to measure the extent of KMS diffusion which is the dependent variable of this model. The 101 companies of total 1,000 samples responded to the survey. To analyze tile results of this empirical study, we performed the multiple regression analysis. As a result, it was shown that the relative advantage, complexity, information system maturity, size, top management support, champion, competitive pressure have influences on both the breadth and the depth diffusions. On the other hand, the organizational culture, valuation and compensation, and uncertainty of environmental factors were not verified to be significant. This empirical study will provide Korean companies with insights into effective ways to diffuse the KMS and succeed in business competition.

• Journal of the Korean institute of surface engineering
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• v.44 no.5
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• pp.207-212
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• 2011

In this study, the change in diffusion coefficient and wear characteristic with depth in the carbonitriding layer of SCM415 steel was discussed. To determine the diffusion coefficient, depth profile of carbon was measured from the surface using the Glow Discharge Spectrometer. In otherwise, measurements of carbide fraction, micro vickers hardness of surface and observation of microstructure have been implemented through the SEM image. $Fe_3$(C,N) layer and effective depth were increased as the time for carbonitriding takes longer. According to wear experiment, the results showed that wear resistance was improved by $Fe_3$(C,N) layer and effective depth.

• Journal of the Korean Institute of Telematics and Electronics
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• v.17 no.5
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• pp.22-27
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• 1980

The two-step diffusion process of boron into silicon has been investigated using a new diffusion source coiled "Spin-on Source". A simple method is proposei which can estimate the junction depth after the two -step diffusion for the cases where the junction depth after the predeposition is not negligible compared with the junction depth after the two-step diffusion. The estimated junction depths are, then, compared with the experimental measurements.surements.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.127-128
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• 2021

In this study, a study was conducted to analyze thermal diffusion according to the depth of concrete exposed to high temperatures. For thermal diffusion analysis, a test specimen in which K-type sheath thermocouples were poured in 0, 10, 20, 30, and 40 mm sections was manufactured, and thermal diffusion measurement was performed through one-sided heating for 180 minutes under heating conditions. As a result of the review, it was shown that as the temperature condition increased, the heat diffusion increased as the depth increased.

• Journal of information and communication convergence engineering
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• v.5 no.4
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• pp.324-327
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• 2007

In this paper, the p-n junction depth with nondestructive method by using scanning electron microscopy (SEM) is determined and conformed. By measuring the critical short circuit current on the p-n junction which induced by electron beam and calculating generation range, the diffusion depth can be obtained. It can be seen that values destructively measured by constant angle lapping and nondestructively by this study almost concur. As this result, it is purposed that diffusion depth of p-n junction can be easily measured by nondestruction. This nondestructive method can be recommended highly to the industrial analysis.

• Journal of Biomedical Engineering Research
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• v.17 no.2
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• pp.227-234
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• 1996

This paper is the study of the diffusion constant in order to calculate the percent oxygenation and percent blood volume using reflectance light within biological tissue. The diffusion constant play major role in percent oxygenation and percent blood volume and varies with the biological material such as hemolyzed blood, whole blood, dermis and epidermis in vivo tissue. The diffusion constant can be modeled to consist of a contribution from bloodless tissue and blood present in tissue. The reflectance light for experimental are red light of 660nm, infrared light of 880nm, green light of 569nm. The correlation between the diffusion constant and biological tissue was analyzed by the intensity of reflectance light at different depth within human limb. The reflectance light was changed in response to physiological changes within biological tissue. The data for diffusion constant were obtained at different depth beneath the surface of the skin and will be utilized to amen the percent oxygenation and percent blood volume.

• Computers and Concrete
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• v.20 no.2
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• pp.185-196
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• 2017

Durability problems initiated from steel corrosion are unseen but critical issues, so that many researches are focused on chloride penetration evaluation. Even if RC (Reinforced Concrete) structures are exposed to normal environment, chloride ingress varies with concrete surface conditions and exposed period. This paper presents an analysis technique for chloride behavior evaluation considering time effect on diffusion and surface conditions assumed as double-layered system. For evaluation of deteriorated surface condition, field investigation was performed for concrete pavement exposed to deicing agent for 18 years. In order to consider enhanced surface concrete, chloride profiles in surface-impregnated concretes exposed to chloride attack for 2 years from previous research were investigated. Through reverse analysis, effectively deteriorated/enhanced depth of surface and the related reduced/enlarged diffusion coefficient in the depth are simulated. The proposed analysis technique was evaluated to handle the chloride behavior more accurately considering changes of chloride ingress within surface layer and decreased diffusion coefficient with time. For the concrete surface exposed to deicing agent, the deteriorated depth and enlarged diffusion coefficient are evaluated to be 12.5~15.0 mm and 200% increasing diffusion coefficient, respectively. The results in concrete containing enhanced cover show 10.0~12.5 mm of impregnated depth and 85% reduction of chloride diffusion in tidal and submerged conditions.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.4
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• pp.263-270
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• 2020

In this study, the physical mechanism and diffusion effects in aluminium implanted silicon was investigated. For fabricating power semiconductor devices, an aluminum implantation can be used as an emitter and a long drift region in a power diode, transistor, and thyristor. Thermal treatment with O₂ gas exhibited to a remarkably deeper profile than inert gas with N₂ in the depth of junction structure. The redistribution of aluminum implanted through via thermal annealing exhibited oxidation-enhanced diffusion in comparison with inert gas atmosphere. To investigate doping distribution for implantation and diffusion experiments, spreading resistance and secondary ion mass spectrometer tools were used for the measurements. For the deep-junction structure of these experiments, aluminum implantation and diffusion exhibited a junction depth around 20 ㎛ for the fabrication of power silicon devices.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.85-86
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• 2022

In this study, a simulation using Company A's COMSOL heat flow program was used to analyze the thermal diffusion simulation according to the depth of the high-temperature exposed cement paste. As a result of the analysis, it showed a similar relationship with the measured temperature as of 180 minutes.