• Journal of Chest Surgery
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• v.40 no.2 s.271
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• pp.97-102
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• 2007

Background: Endovenous laser treatment has recently been introduced as a less invasive technique, with many good results reported, A 980-nm diode laser was used on the great saphenous vein (GSV) occlusions in patients with varicose veins, due to GSV reflux, and the therapeutic effects analyzed. Material and Method: Between September 2003 and February 2006, 238 patients (332 cases) with GSV reflux underwent endovenous laser treatment with a 980-nm diode laser. Operative procedures were simultaneous endovenous laser treatment and ambulatory phlebectomy. The preoperative clinical findings, postoperative complications and postoperative duplex US follow up results at 1 and 3 months were reviewed. Result: Postoperative complications were ecchymosis in almost cases, paresthesia 68 cases (20.5%) and skin burn in 3 cases (0.9%). Follow up duplex US revealed 26 and 10 cases at 1 and 3 months of GSV reflux or partial recanalization, with therapeutic success rates of 91.3 and 87.9%, respectively. Conclusion: The treatment of GSV occlusion with an endovenous laser is less invasive than traditional GSV stripping, but relatively high recanalization was experienced, possibly due to inadequate laser power, laser fiber pullback speed or an extremely dilated GSV. However, continuous attempts will be required to reduce the recanalization after the procedure, with accurate follow up using duplex US.

• Journal of Society of Preventive Korean Medicine
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• v.15 no.1
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• pp.49-69
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• 2011

Objective : The object of this study was to observe the effects of Lonicerae Flos (LF) aqueous extracts on lipopolysaccharide (LPS)-induced rat acute lung injury. Method : Five different dosages of LF extracts were orally administered once a day for 28 days before LPS treatments, and then all rats were sacrificed after 5 hour-treatment of LPS. Eight groups of 16 rats each were used in the present study. The following parameters caused by LPS treatment were observed ; body weights, lung weights, pulmonary transcapillary albumin transit, arterial gas parameters (pH, $PaO_2$ and $PaCO_2$) bronchoalveolar lavage fluid (BALF) protein lactate dehydrogenase (LDH), and proinflammatory cytokines tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-$1{\beta}$) contents, total cell numbers, neutrophil and alveolar macrophage ratios, lung malondialdehyde (MDA), myeloperoxidase (MPO), proinflammatory cytokines TNF-${\alpha}$ and IL-$1{\beta}$ contents. In addition, the histopathologic changes were observed in the lung in terms of luminal surface of alveolus, thickness of alveolar septum, number of polymorphonuclear neutrophils. Result : As results of LPS-injection, dramatical increases in lung weights, pulmonary transcapillary albumin transit increases, increases in $PaCO_2$, decreases in pH of arterial blood and $PaO_2$, increases of BALF protein, LDH, TNF-${\alpha}$ and IL-$1{\beta}$ contents, total cells, neutrophil and alveolar macrophage ratios, TNF-${\alpha}$ and IL-$1{\beta}$ contents increases were detected with decreases in LSA and increases of alveolar septum and PMNs numbers, respectively as compared with intact control. These are means that acute lung injuries (resembling acute respiratory distress syndrome) are induced by treatment of LPS mediated by inflammatory responses, oxidative stress and related lipid peroxidation in the present study. However, these LPS-induced acute lung injuries were inhibited by 28 days continuous pretreatment of 250 and 500mg/kg of LF extracts. Because of lower three dosages of LF treated groups, 31.25 and 62.5 and 125mg/kg did not showed any favorable effects as compared with LPS control, the effective dosages of LF in LPS-induced acute lung injuries in the present study, is considered as about 125mg/kg. The effects of 250mg/kg of LF extracts showed almost similar effects with ${\alpha}$-lipoic acid 60mg/kg in preventing LPS-induced acute lung injuries. Conclusion : It seems that LF play a role in protecting the acute respiratory distress syndrome caused by LPS.

• Journal of Biomedical Engineering Research
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• v.24 no.4
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• pp.319-328
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• 2003

The purpose of this paper is to develop a medical laser system using the semiconductor diode laser in order to photodynamic cancel therapy as a light source. The ideal light source for photodynamic therapy would be a homogeneous nondiverging light with variable spot size and specific wavelength with stability. After due consideration in this point, in this paper, we used a diode laser resonator of 635nm wavelength. The development laser system have a statistical laser out beam with accuracy control using the constant current control of method and clinic-friendly with compact. In order to protect the diode resonator from the over-current, the rush-current and electrical fault, we specially designed. The most importance therapeutic factor are the radiation mode for cancer therapy. So we developed the radiation mode of CW(Continuous Wave), long pulse, short pulse, and burst pulse and can adjust the exposure time from several milli-second to several minute. The experimental result shows that laser beam power was increased linear from 10mW to 300mW according to the increasing input current and the increasing exposure time. The developed new compact diode laser system have a stability of output power and specific wavelength with easy control and transportable for many applications of PDT.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.5079-5086
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• 2011

The purpose of this study was to examine the oral health status and knowledge of dental laboratory technology student for the community to improve oral health and oral health education to help. The subjects in this study were 160 students in dental laboratory technology at the University located in Chung-cheong and surveyed from November 2010 to December 2010. The finding of the study were as follows: The differences in oral care knowledge according general characteristics of subjects was statistically significant to the gender was higher in men than women, age was higher and higher the grade was higher in grade level(p<0.05). The differences in oral care knowledge according oral health status of subjects was statistically significant to regarding the frequency of tooth brushing was highest rate in five times, method was on the side tooth higher and using the dental floss and interdental brush are used by the higher availability(p<0.05). Thus, in the classroom oral health education and continuous learning from the people know that oral health care could differ. Oral health education in local communities to increase opportunities and people will need to improve oral health.

• Journal of Korean Home Economics Education Association
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• v.30 no.3
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• pp.195-213
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• 2018

The purpose of this study is to verify the effect by developing and applying a new program for improvement of creative problem solving ability and collaborative ability. Development of a sewing practice program was performed through the ADDIE model. The subjects of the study were 1^st grade middle school students and the research plan of the study was pretest-posttest control group design. The study method was performed by mixing the quantitative and qualitative analysis methods. Results of this study are as follows. First, the students in the experimental group showed higher creative problem solving ability than the students in the control group, but the difference was not significant at the 5% significance level. Qualitative analysis results indicated that creative problem solving ability is closely related to learning experiences involving the 'generation of diverse ideas', 'rebirth of creative ideas', 'self-directed learning plan', 'active problem solving', 'immediate feedback'. Second, the students in the experimental group showed a significantly higher level of collaborative ability than the students in the control group. This demonstrated that the program developed in this study had an effect on fostering the collaborative ability of middle school students. It was found that collaborative ability is closely related to learning experiences involving 'forming a positive atmosphere', 'continuous interaction', and 'working together'.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.3
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• pp.114-123
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• 2016

The effective feature extraction method for unmanned aerial vehicle (UAV) detection is proposed and verified in this paper. The UAV engine sound is harmonic complex tone whose frequency ratio is integer and its variation is continuous in time. Using these characteristic, we propose the feature vector composed of a mean and standard deviation of difference value between fundamental frequency with 1st overtone as well as mean variation of their frequency. It was revealed by simulation that the suggested feature vector has excellent discrimination in target signal identification from various interfering signals including frequency variation with time. By comparing Fisher scores, three features based on frequency show outstanding discrimination of measured UAV signals with low signal to noise ratio (SNR). Detection performance with simulated interference signal is compared by MFCC by using ELM classifier and the suggested feature vector shows 37.6% of performance improvement As the SNR increases with time, the proposed feature can detect the target signal ahead of MFCC that needs 4.5 dB higher signal power to detect the target.

• The Korean Journal of Urological Oncology
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• 제15권3호
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• pp.178-186
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• 2017

Purpose: Poloxamer 407 (P407) thermo-sensitive hydrogel formulations were developed to enhance the retention time in the urinary bladder after intravesical instillation. Materials and Methods: P407 hydrogels (P407Gels) containing 0.2 w/w% fluorescein isothiocyanate dextran (FD, MW 4 kDa) as a fluorescent probe were prepared by the cold method with different concentrations of the polymer (20, 25, and 30 w/w%). The gel-forming capacities were characterized in terms of gelation temperature (G-Temp), gelation time (G-Time), and gel duration (G-Dur). Homogenous dispersion of the probe throughout the hydrogel was observed by using fluorescence microscopy. The in vitro bladder simulation model was established to evaluate the retention and drug release properties. P407Gels in the solution state were administered to nude mice via urinary instillation, and the in vivo retention behavior of P407Gels was visualized by using an in vivo imaging system (IVIS). Results: P407Gels showed a thermo-reversible phase transition at $4^{\circ}C$ (refrigerated; sol) and $37^{\circ}C$ (body temperature; gel). The G-Temp, G-Time, and G-Dur of FD-free P407Gels were approximately $10^{\circ}C-20^{\circ}C$, 12-30 seconds, and 12-35 hours, respectively, and were not altered by the addition of FD. Fluorescence imaging showed that FD was spread homogenously in the gelled P407 solution. In a bladder simulation model, even after repeated periodic filling-emptying cycles, the hydrogel formulation displayed excellent retention with continuous release of the probe over 8 hours. The FD release from P407Gels and the erosion of the gel, both of which followed zero-order kinetics, had a linear relationship ($r^2=0.988$). IVIS demonstrated that the intravesical retention time of P407Gels was over 4 hours, which was longer than that of the FD solution (<1 hour), even though periodic urination occurred in the mice. Conclusions: FD release from P407Gels was erosion-controlled. P407Gels represent a promising system to enhance intravesical retention with extended drug delivery.

• Korean Journal of Remote Sensing
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• v.25 no.1
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• pp.71-83
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• 2009

This paper is written to analyze possible problems encountered with the existing data for the monitoring of land use and land cover change over the Korean peninsula and, further, to provide technical alternatives for the future land monitoring over the area. The oldest type of non-spatial data related to the land use change are cadastral statistics obtained since 1911. Annual statistics of cadastral data in early years (before 1942) can be used to assess land use change over the area. However, the cadastral statistics after the Korean War are not very appropriate for land use monitoring since the land class in cadastral data does not always correspond with actual land cover status. Majority of spatial data available for land monitoring over the area are land cover maps classified from satellite imagery since early 1970's. To analyze the suitability of land cover maps that were produced by two separate institutes with about 10 years interval, we conducted simple change detection analysis using these maps. These maps were not quite ready to be compared each other, in which they did not have the same class definition, classification method, and geometric registration. To achieve continuous and effective monitoring of land use and land cover change, particularly over North Korea, we should have a standard scheme in type and season of satellite imagery, image classification procedure, and class definition, which also should correspond to international standards.

• Korean Journal of Comparative Education
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• v.27 no.3
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• pp.101-127
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• 2017

The purpose of this study is to analyze how the debates on learning and learning outcomes in global education agendas have changed and to understand the discourses and issues about learning under the agendas, and finally based on the understanding, to know what is the implication we should take in international education development cooperation in Korea. To do this, this study critically analyzed 1) what is the main features and directions, and 2) the method and limitation in handling learning concept on three major global education forums which are Jomtien global education forum in 1990, Dakar in 2000, and Incheon in 2015. Major finding shows that there are little learning concept discussed in Jomtien and Dakar forums and in SDGs education agenda, learning is vaguely defined and discussed and there are problems of too much focus on learning outcomes itself and absence of study on proper assessment system. Major lessons and implications for international education development cooperation could be stated that postcolonial perspectives and learner centered approaches is required in developing countries's education ecology. And continuous support for sustainable development for learners' capacity should be underlined. We needs to focus on developing software not hardware from the first of educational ODA. Finally, it is needed to embed within pedagogical approaches.

• Korean Journal of Construction Engineering and Management
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• v.20 no.6
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• pp.34-43
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• 2019

The maintenance cost for road pavement is gradually increasing due to the continuous increase in road extension as well as increase in the number of old routes that have passed the public period. As a result, there is a need for a method of minimizing costs through preventative grievance preventive maintenance requires the establishment of a strategic plan through accurate prediction of road pavement. Hence, In this study, the deep neural network(DNN) and the recurrent neural network(RNN) were used in order to develop the expressway pavement damage prediction model. A superior model among these two network models was then suggested by comparing and analyzing their performance. In order to solve the RNN's vanishing gradient problem, the LSTM (Long short-term memory) circuits which are a more complicated form of the RNN structure were used. The learning result showed that the RMSE value of the RNN-LSTM model was 0.102 which was lower than the RMSE value of the DNN model, indicating that the performance of the RNN-LSTM model was superior. In addition, high accuracy of the RNN-LSTM model was verified through the comparison between the estimated average road pavement condition and the actually measured road pavement condition of the target section over time.