• Proceedings of the Korean Society of Applied Pharmacology
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• 2004.11a
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• pp.18-34
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• 2004

This paper will review data obtained primarily from our preclinical investigations that show that exposure to stress has a significant impact on drug taking. Stress increases reward associated with psychomotor stimulants, possibly through a process similar to sensitization, and a growing clinical literature indicates that there is also a link between substance abuse and stress in human addicts. One explanation for the high concordance between stress-related disorders and drug addiction is the self-medication hypothesis, which suggests that a dually-diagnosed person often uses the abused substance to cope with tension associated with life stressors or to relieve symptoms of anxiety and depression resulting from a traumatic event. However, another characteristic of drug self-administration is that drug delivery and its subsequent effects on the HPA axis are under the direct control of the individual. This controlled activation of the HPA axis may result in the production of an internal state of arousal or stimulation that is actually sought by the individual (i.e., the sensation-seeking hypothesis). During abstinence, however, exposure to stressors or drug-associated cues can stimulate the HP A axis to remind the individual about the effects of the abused substance, thus producing craving and promoting relapse. Stress reduction, either alone or in combination with pharmacotherapies targeting the HPA axis may prove beneficial in reducing cravings and promoting abstinence in individuals seeking treatment for addiction. Of primary importance is to reduce the impact of cocaine-associated environmental stimuli on the HPA axis so that they no longer function as triggers for relapse.

• Journal of Communications and Networks
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• v.11 no.1
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• pp.57-71
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• 2009

Networking together hundreds or thousands of cheap sensor nodes allows users to accurately monitor a remote environment by intelligently combining the data from the individual nodes. As sensor nodes are typically battery operated, it is important to efficiently use the limited energy of the nodes to extend the lifetime of the wireless sensor network (WSN). One of the fundamental issues in WSNs is the coverage problem. In this paper, the border coverage problem in WSNs is rigorously analyzed. Most existing results related to the coverage problem in wireless sensor networks focused on planar networks; however, three dimensional (3D) modeling of the sensor network would reflect more accurately real-life situations. Unlike previous works in this area, we provide distributed algorithms that allow the selection and activation of an optimal border cover for both 2D and 3D regions of interest. We also provide self-healing algorithms as an optimization to our border coverage algorithms which allow the sensor network to adaptively reconfigure and repair itself in order to improve its own performance. Border coverage is crucial for optimizing sensor placement for intrusion detection and a number of other practical applications.

• Journal of Korean society of Dental Hygiene
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• v.13 no.2
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• pp.287-295
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• 2013

Objectives : This study was to infectify variable the factors influencing oral health behaviors in high school students. Methods : Data were collected from 241 high school students Busan and Kyungnam Province for four weeks in July 2012. The SPSS 18.0 program was used for data analysis, which included t-test, correlation analysis, multiple logistic regression analysis. Results : Positive correlation in the order of social support(r=.381), self-efficiency(r=.309) with perceived benefit of oral health behavior and social support with total heal index(r=.298) are shown. In the contrary, the relation between social support(r=-.400), subjective oral health status(r=-.222) with impairments of oral health behavior have negative one. Experience in three or more tooth brushing has an effect on social support and subjective oral health status(p<.05). Perceived benefit(p<.001) of oral health life and subjective oral health status(p<.05) are affected by recognition of correct tooth brushing. Intake of harmful food on tooth has an effects on perceived benefit, self-efficiency, total health index and subjective oral health status(p<.05). Conclusions : In conclusion, systematic activation of oral health education in school and correct self-activity of oral health will promote oral health of youth.

• Mass Spectrometry Letters
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• v.2 no.1
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• pp.24-27
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• 2011

Hyperthermal ion/surface collisions of bromotoluene radical cations were studied using perfluorinated (F-SAM) and hydroxyl-terminated (OH-SAM) self-assembled monolayer surfaces in a tandem mass spectrometer with BEEQ geometry. The isomers were differentiated by ion abundance ratios taken from surface-induced dissociation (SID). The dissociation rate followed the order of ortho > meta > para isomers. The peak abundance ratio of m/z 51 to m/z 65 showed the best result to discern the isomers. A dissociation channel leading to tolylium ion was suggested to be responsible for the pronounced isomeric differences. The capability of SID to provide high-energy activation with narrow internal energy distribution may have channeled the reaction into the specific dissociation pathway, also facilitating small differences in reaction rates to be effective in the spectral time window of this experiment. All of the molecular ions experiencing reactive collisions with the F-SAM surface undergo transhalogenation, in which a fluorine atom on the surface replaces the bromine in the incoming ions. This reactive collision was dependent on the laboratory collision energy occurring in ca. 40.75 eV range.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.2
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• pp.66-72
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• 1995

Using the Si/SiGe layer grown by solid source molecular beam epitaxy(SSMBE) on the LOCOS-patterned wafers, an emitter-base self-aligned hterojunction biplar transistor(HBT) with the polysilicon-emitter and the silicon germanium(SiGe) base has been fabricated. Trech isolation process, planarization process using a chemical-mechanical poliching, and the selectively implanted collector(SIC) process were performed. A titanium disilicide (TiSi$_{2}$), as a base electrode, was used to reduce an extrinsic base resistance. To prevent the strain relaxation of the SiGe epitaxial layer, low temperature (820${^\circ}C$) annealing process was applied for the emitter-base junction formation and the dopant activation in the arsenic-implanted polysilicon. For the self-aligned Si/SiGe HBT of 0.9${\times}3.8{\mu}m^{2}$ emitter size, a cut-off requency (f$_{T}$) of 17GHz, a maximum oscillation frequency (f$_{max}$) of 10GHz, a current gian (h$_{FE}$) of 140, and an emitter-collector breakdown voltage (BV$_{CEO}$) of 3.2V have been typically achieved.

• Journal of the Semiconductor & Display Technology
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• v.13 no.4
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• pp.27-32
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• 2014

The cure properties of self-extinguishing epoxy resin systems with different charge transfer type latent catalysts were investigated, which are composed of YX4000H as a biphenyl epoxy resin, MEH-7800SS as a hardener, and charge transfer type latent catalysts. We designed and used five kinds of charge transfer type latent catalyst and compared to epoxy resin systems with Triphenylphosphine-Benzoquinone(TPP-BQ) as reference system. The cure kinetics of these systems were analyzed by differential scanning calorimetry with an isothermal approach, the kinetic parameters of all systems were reported in generalized kinetic equations with diffusion effects. The epoxy resin systems with Triphenylphosphine-Quinhydrone(TPP-QH), Triphenylphosphine-Benzanthrone(TPP-BT) and Triphenylphosphine-Anthrone(TPP-AT) as a charge transfer type latent catalyst showed a cure conversion rate of equal or higher rate than those with TPP-BQ. These systems with TPP-QH and Triphenylphosphine-Tetracyanoethylene(TPP-TCE) showed a critical cure reaction conversion of equal or higher conversion than those with TPP-BQ. The increases of cure conversion rates could be explained by the decrease of the activation energy of these epoxy resin systems. It can be considered that the increases of critical cure reaction conversion would be dependent on the crystallinity of the biphenyl epoxy resin systems.

• Journal of Information Technology Services
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• v.9 no.3
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• pp.65-82
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• 2010

Mobile applications market has emerged as new business model. The purpose of this study is to analyze the factors of mobile applications adoption. Based on prior studies of TAM and mobile technology/service, service quality, user experience, OS compatibility, self-efficacy, innovativeness, perceived usefulness, perceived ease of use, and cost were identified as affecting factors of mobile applications adoption. According to the results, service quality is significantly related to the perceived usefulness, and self-efficacy and innovativeness are significantly related to the perceived ease of use. User experience was also found to be related to both the perceived usefulness and the perceived ease of use. In case of OS compatibility, it was found to be significantly related to the perceived ease of use, but not to the perceived usefulness. Both the perceived usefulness and the perceived ease of use were found to be related to the adoption of mobile applications. However, cost was not found to be significant to the relationship between the perceived usefulness/the perceived ease of use and the adoption of mobile applications. This study contributes to provide the base of activation strategies and practical implications for mobile applications.

• Steel and Composite Structures
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• v.31 no.2
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• pp.149-158
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• 2019

The force-deformation behavior, strain distribution and failure modes of a variable damping self-centering brace (VD-SCB) are theoretically analyzed, experimentally studied, and numerically simulated to guide its design. The working principle of the brace is explained by describing the working stages and the key feature points of the hysteretic curve. A large-scale brace specimen was tested under different sinusoidal excitations to analyze the recentering capability and energy dissipation. Results demonstrate that the VD-SCB exhibits a full quasi-flag-shaped hysteretic response, high ultimate bearing capacity, low activation force and residual deformation, and excellent recentering and energy dissipation capabilities. Calculation equations of the strain distribution in different parts of the brace are proposed and are compared with the experimental data and simulated results. The developments of two failure modes are compared. Under normal circumstances, the brace fails due to the yielding of the spring blocking plates, which are easily replaced to restore the normal operating conditions of the brace. A brief description of the design procedure of the brace is proposed for application.

• Journal of the Economic Geographical Society of Korea
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• v.20 no.1
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• pp.105-120
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• 2017

Chung-ju enterprise city was selected as a model enterprise city in 2005, and the city is planned to finish the construction in 2020. The main purpose of this study is to suggest the developing strategy and activation plan for Chung-ju enterprise city based on the enterprise city of developed countries. Chung-ju enterprise city will grow into well-being self-sufficient city due to the cutting edge knowledge, industry-centered cluster which is the new growth industry of Chungchungbuk-do and the surrounding excellent nature. For the success of Chung-ju enterprise city, the cooperation between developing agents such as companies, universities, local government, and central government is important. The leading companies and researching facilities should be attracted as well. Also, non-profit exclusive organization must be installed. The successful development of Chung-ju enterprise city means the success of balanced region development policy which will solve overpopulation of capital region and unbalance of Korea.

• International Journal of Control, Automation, and Systems
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• v.6 no.3
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• pp.453-459
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• 2008

The neural network is currently being used throughout numerous control system fields. However, it is not easy to obtain an input-output pattern when the neural network is used for the system of a single feedback controller and it is difficult to obtain satisfactory performance with when the load changes rapidly or disturbance is applied. To resolve these problems, this paper proposes a new mode to implement a neural network controller by installing a real object for control and an algorithm for this, which can replace the existing method of implementing a neural network controller by utilizing activation function at the output node. The real plant object for controlling of this mode implements a simple neural network controller replacing the activation function and provides the error back propagation path to calculate the error at the output node. As the controller is designed using a simple structure neural network, the input-output pattern problem is solved naturally and real-time learning becomes possible through the general error back propagation algorithm. The new algorithm applied neural network controller gives excellent performance for initial and tracking response and shows a robust performance for rapid load change and disturbance, in which the permissible error surpasses the range border. The effect of the proposed control algorithm was verified in a test that controlled the speed of a motor equipped with a high speed computing capable DSP on which the proposed algorithm was loaded.