• Journal of Pharmaceutical Investigation
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• v.37 no.2
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• pp.95-99
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• 2007

To develop topical nitroglycerin (NTG) preparation far chronic anal fissure treatment, the release rate of NTG should be controlled carefully. For this, microemulsion was prepared from the phase diagram construction with Cremophor ELP, ethanol and Labrafil $M1944CS^{(R)}$ and the topical gel was prepared by dispersing NTG containing microemulsion into hydrophilic polymers. in viかo release characteristics were evaluated with Franz diffusion cell using cellulose membrane and compared with control hydrogels. The release rate of NTG was followed $1^{st}$ order kinetics and, when comparing the NTG release from control hydrogel with that from the microemulsion-based hydrogel, the NTG release rate was controlled by the content of polymers within continuous phase and the concentration of dispersed phase.

• Korean Institute of Interior Design Journal
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• v.20 no.4
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• pp.136-144
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• 2011

The purpose of this research is to analyze the manifestation of children's color education in the software in order to evaluate conditions of color education as well as improvement of its direction. The procedure and method of the research is begun from evaluating the characteristic of children's developmental stage, content analysis of the nation's organization of color education and analysis and evaluation of education program through the investigation on 8 different softwares in reward for the tournament. The results are as followings; First, the research shows that the elementary school stage of color education is inadequate in comparison to children's cognitive developmental stage. Second, most of the color theory was composed of characteristic of a color, stimulation of emotion and effects of psychology. Considering of children's cognitive development, it is necessary to make up for the basic of color theory and the system of color. Third, Softwares of color education program for 1 st. and 2nd grade in elementary school was so rare that it should be properly developed and made for systematic contents. Fourth, color education for the 5th and 6th grade children remained in understanding basic characteristics of the color which is below the par and brings the necessity for more professional and structural contents.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.5
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• pp.148-155
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• 2011

This study analyzes stress, fatigue and vibration at clutch on the rotation of wheel. Eigenfrequencies from 1'st to 6'th order about clutch assembly are shown with the vibration at more than 800Hz. Maximum equivalent stress is shown with the frequency of 800Hz in case of the harmonic vibration applied with force. Among the cases of nonuniform fatigue loads, 'SAE bracket history' with the severest change of load becomes most unstable but 'Sample history' becomes most stable. In case of 'Sample History' with the average stress of 0MPa to $-10^5$ MPa and the amplitude stress of 0MPa to $10^5$ MPa, the possibility of maximum damage becomes 3.23%. This stress state can be shown with 6 times more than the damage possibility of 'SAE bracket history' or 'SAE transmission'. The structural result of this study can be effectively utilized with the safe design of clutch.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.10a
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• pp.173-176
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• 2007

The characteristics of the tool system give many effects into the costs and qualities for the finished components. This study proposes a new method for manufacturing of high manufacturing productivity, production process reduction and low cost through back pressure forming. The Lock-up hub is manufactured through many processes, such as upsetting($1^{st}$ Forming), piercing, direct extrusion($2^{nd}$ Forming), final sizing process($3^{rd}$ Forming). In this study, process design for closed-die forging of a Lock-up hub used for a component of automobile transmission was made using three-dimensional finite element simulations, and the strain distributions and velocity distributions are investigated through the post processor. The rigid-plastic finite-element method for back pressure forging has been used in order to reduce development time and die cost. Using the FEM simulation, we found the optimum value of back pressure. The prototypes of Lock-up hub parts were forged into the net-shape. In the experiment, lead precision of tooth are measured by the CCMM(Contact Coordinate Measuring Machine). The dimensional accuracy of forged part was improved up to the 40% when back press was applied.

• Journal of the Ergonomics Society of Korea
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• v.32 no.5
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• pp.443-448
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• 2013

Objective: Purposes of this study are selecting main factors in evaluating the usability of mobile navigation and comprehending mutual importance among the factors. Background: Mobile navigation services have been more diffused than ever as the number of smartphone users sharply increased. However users are having trouble with the usage of mobile navigation services due to the lack of research in the area. Method: In order to attain results, general research on mobile navigation, 1st general survey, and 2nd comparative survey on navigation UI experts were performed. Empirical studies about the results were performed using AHP method. Results: As the result of AHP analysis, accuracy was drawn out to be the most important factor followed by accessibility and visibility. Regarding the characteristics of navigation system, the provision of accurate POI(Point of Interest) was considered to be the most important factor for the experts. And effectiveness was considered to be the most important, followed by satisfaction and efficiency. Conclusion: When evaluating the usability of mobile navigation, prior factors such as accuracy, visibility, and aesthetics should be considered in advance and general evaluation concentrated on effectiveness must be performed. Application: The results of this study are expected to be a fundamental data to mobile navigation design.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.2
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• pp.185-194
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• 2016

It is essential for generating the synthetic image to test and evaluate a guided missile system in the hardware-in-the-loop simulation. In order to make the evaluation results to be more reliable, the extent of fidelity and rendering performance of the synthetic image cannot be left ignored. There are numerous challenges to simulate the LWIR sensor signature of sea surface depending on the incident angle, especially in the maritime environment. In this paper, we investigate the key factors in determining the apparent temperature of sea surface and propose the approximate formula consisting of optical characteristics of sea surface and sky radiance. We find that the greater the incident angle increases, the larger the reflectivity of sea surface, and the greater the water vapor concentration in atmosphere increases, the larger the amount of sky radiance. On the basis of this information, we generate the virtual maritime environment in LWIR region using the SE-WORKBENCH, physically based rendering software. The margin of error is under seven percentage points.

• Journal of ILASS-Korea
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• v.26 no.2
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• pp.96-103
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• 2021

In order to improve the overall efficiency and meet the emission regulations of boiler systems, the heat exchanging methods between inlet air and exhaust gas have been used in boiler systems, named as the waste-heat-recovery condensing boiler. Recently, to further improve the overall efficiency and to reduce the NOx emission simultaneously, the concept of the water injection into the inlet air is introduced. This study suggests the models for the optimized design parameters of water injection for waste-heat-recovery condensing boilers and performs the analysis regarding the water injection amount and droplet sizes for the optimized water injection. At first, the required amount of the water injection was estimated based on the 1^st law of thermodynamics under the assumption of complete evaporation of the injected water. The result showed that the higher the inlet air and exhaust gas temperature into the heat exchanger, the larger the amount of injected water is needed. Then two droplet evaporation models were proposed to analyze the required droplet size of water injection for full evaporation of injected water: one is the evaporation model of droplet in the inlet air and the other is that on the wall of heat exchanger. Based on the results of two models, the maximum allowable droplet sizes of water injection were estimated in various boiler operating conditions with respect to the residence time of the inlet air in the heat exchanger.

• Journal of Korean Academy of Nursing
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• v.30 no.1
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• pp.39-46
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• 2000

This study, was done to compare the nursing education systems of China and South Korea (Korea), then, on the basis of this comparison, to examine the direction of nursing education in China. The results the study are as follows : 1. Nursing education in Korea was influenced by social change, political policy, but as it was established, nurses in Korea, were able actively involved in presenting nursing education development proposals to the government, and in developing nursing education through their own efforts. Nursing education in China developed through the political policy of a socialist Country. During the period of modernization after 1977, a nursing education developed very quickly, In 1983, the first baccalaureate nursing education program was established and, in 1992, the first masters program was opened. 2. In Korea, there are two nursing education systems; diploma and baccalaureate, and there is only one entry level, high school graduation. In China today, on the other hand, there are three types of nursing education systems; technical, diploma, and baccalaureate, and they have middle school and high school graduation as the two levels of entry. 3. There are similarities between China and Korea in curriculums for nursing education which include the major nursing concepts. But in descriptions of the education objectives, China the emphasis is on training the 'expert' in clinical nursing which is not consistent with their educational philosophy. Korea differs from China in that the focus is on training for 'multiple ability' to be used in both clinical and community environments. 4. In Korea, the curriculum is organized with the theoretical and clinical experience combined. The curriculum is oriented to the life cycle and human developmental process. In China, however, the curriculum is organized so that after finishing the theoretical part of the curriculum, the students begin a one year intensive field experience in which the major clinical field is the hospital, and the focus is on disease oriented care and research ability. 5. In order for nurses to be proposed to address nursing education system needs follows : to change as The new nursing education system should be baccalaureate education in order to improve the education level in all nursing education programs, to develop doctoral programs, to open nurse specialist programs, and to develop a new curriculum based nursing philosophy and health delivery system change. New nursing curriculum for health care in China in the 21st century should be directed by a framework based on nursing philosophy, objectives and nursing content. In conclusion, the study will contribute China nursing education system revolution for policy develop and curriculum research. According to these results, in the future, nurses in China should be more actively involved in research and in a nursing education revolution, Also they should be involved in building information networks and in developing long term projects in nursing education.

• Journal of Photoscience
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• v.9 no.2
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• pp.225-228
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• 2002

Bcl-2 is a member of large bcl-2 family and protects cells from apoptosis. Using bcl-2-expressing adenovirus vector (Ad-bc1-2), we investigated the effect of bc1-2 on UVB-induced apoptosis. Adenovirus vector efficiently introduced bc1-2 gene in cultured normal mouse keratinocytes (NMK cells); almost all NMK cells (lx10$^{6}$ ) were transfected at Ixl0$^{8}$ PFU/ml. Bcl-2-transfected NMK cells were significantly resistant to UVB-induced apoptosis with the suppressive effect dependent on bcl-2-expression level. Following UVB irradiation caspase 8, 3, 9 activities were stimulated in NMK cells, while in bc1-2-transfected cells, only caspase 8, but not caspase 3 or 9 activities were stimulated. In order to investigate the effect of bc1-2 in vivo, topical application of Ad-bc1-2 on tape-stripped mouse skin was performed. Following the application, Bc1-2 was efficiently overexpressed in almost all viable keratinocytes. The expression was transient with the maximal expression of Bc1-2 at 1st day following the application of lxl0$^{9}$ PFU in 200ml. The introduced Bc1-2 remained at least for 6 days. UVB irradiation (1250 J/m$^2$) induced apoptosis within 12 h and the maximal effect was observed at 24 h in control mouse skin. Bc1-2-transfected mice skin were resistant to UVB-induced apoptosis. Topical application of empty adenovirus vector alone had no effect on Bc1-2 expression or UVB-induced apoptosis. These results indicate that adenovirus vector is an efficient gene delivery system into keratinocytes and that Bcl-2 is a potent inhibitor of UVB-induced apoptosis both in vitro and in vivo.

• Journal of the Korean Society for Precision Engineering
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• v.5 no.4
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• pp.48-58
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• 1988

This study was undertaken to observe the formation behavior of ferro- magnetic phase in Mn-Al-Cu Alloys. The alloy selected for this investigation was 70% Mn-29% Al-1% Cu. This pre-allyed pig was prepared to the cylinderical castings using an Induction furnace after homogenizing at $1100^{\circ}C$ for 2hr, the specimens were cooled by cooling methods. Subwequent isothermal heat treatments were followed at $550^{\circ}C$ for various periods of time at predetermined(1-1000min). The formation behavior of ferromagnetic phase was investigated by measurements of magnetic properties of the specimens at each stage of heat treatment, and optical microscopic esamination and X-Ray diffraction analyses were also employed. By this basic experimental results, the conclusions are as follows 1) In order to obtain much amount of ferromagnetic phase, the optimum average cooling rate was about 7.35-$16.4^{\circ}C$/sec($1100^{\circ}C$-$600^{\circ}C$). 2) We verified the decomposition of {\tau} phase to {\beta} -Mn and {\gamma} , as the specimens were homogenized at $1100^{\circ}C$ for 12hr, then heat-treased at $550^{\circ}C$ for 1-1000min. 3) A condition of optimum heat treatments in Mn-Al-Cu permanent mag-netic alloys showed that after homogenizing at $1100^{\circ}C$ for 2hr, the speciments were cooled in air or furnace(A) and subsequent heat treatments at $550^{\circ}C$ for 1-30min. The maximum magnetic properties were measured as follows: Air cooling; Br=1200(Gause), bHc=100(oe), (BH)max=0.07(MGOe) Furnace cooling(A);Br=950(Gauss), bhe=80(Oe), (BH)max=0.05(MGOe)